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Ionothermal Carbonization of Sugarcane Bagasse in 1-Alkyl-3-methylimidazolium Ionic Liquids: Insights into the Role of the Chloroferrate Anion. J Phys Chem B 2024; 128:3485-3498. [PMID: 38549268 DOI: 10.1021/acs.jpcb.3c08457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
We report the ionothermal carbonization (ITC) of lignocellulosic biomass in imidazolium tetrachloroferrate ionic liquids (ILs) as an advantageous approach for the preparation of nanostructured carbonaceous materials, namely, ionochars. In a previous study, we investigated the role of the imidazolium cation and demonstrated the possibility of controlling both the textural and morphological properties of ionochars by cation engineering. Although essential for providing intermediate Lewis acidity and relatively high thermal stability, the role of the chloroferrate anion is still open to debate. Herein, we investigated the ITC of sugarcane bagasse and its main component, cellulose, in 1-alkyl-3-methylimidazolium ILs with different chloroferrate anions. We identified anionic speciation and its impact on the properties of the IL by Raman spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. The obtained ionochars were characterized by gas physisorption, electron microscopy, Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and 13C solid-state CP-MAS NMR spectroscopy. We show that the anionic species have a predominant impact on the textural and morphological properties of the ionochars.
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A fast and efficient method for the analysis of α-dicarbonyl compounds in aqueous solutions: Development and application. CHEMOSPHERE 2023; 319:137977. [PMID: 36736840 DOI: 10.1016/j.chemosphere.2023.137977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 01/24/2023] [Accepted: 01/26/2023] [Indexed: 06/18/2023]
Abstract
Among the highly oxygenated species formed in situ in the atmosphere, α-dicarbonyl compounds are the most reactive species, thus contributing to the formation of secondary organic aerosols that affect both air quality and climate. They are ubiquitous in the atmosphere and are easily transferred to the atmospheric aqueous phase due to their high solubility. In addition, α-dicarbonyl compounds are toxic compounds found in food in biochemistry studies as they can be produced endogenously through various pathways and exogenously through the Maillard reaction. In this work, we take advantage of the high reactivity of α-dicarbonyl compounds in alkaline solutions (intramolecular Cannizzaro reaction) to develop an analytical method based on high performance ion chromatography. This fast and efficient method is suitable for glyoxal, methylglyoxal and phenylglyoxal which are detected as glycolate, lactate and mandelate anions respectively, with 100% conversion at pH > 12 and room temperature for exposure times to hydroxide ranging from 5 min to 4 h. Diacetyl is detected as 2,4-dihydroxy-2,4-dimethyl-5-oxohexanoate due to a base-catalysed aldol reaction that occurs before the Cannizzaro reaction. The analytical method is successfully applied to monitor glyoxal consumption during aqueous phase HO∙-oxidation, an atmospherically relevant reaction using concentrations that can be observed in fog and cloud water. The method also reveals potential analytical artifacts that can occur in the use of ion chromatography for α-hydroxy carboxylates measurements in complex matrices due to α-dicarbonyl conversion during the analysis time. An estimation of the artifact is given for each of the studied α-hydroxy carboxylates. Other polyfunctional and pH-sensitive compounds that are potentially present in environmental samples (such as nitrooxycarbonyls) can also be converted into α-hydroxy carboxylates and/or nitrite ions within the HPIC run. This shows the need for complementary analytical measurements when complex matrices are studied.
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Comparison of severe hypercholesterolemia patients with and without pathogenic variants. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.2362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Introduction
A pathogenic variant causally related to familial hypercholesterolemia (FH) is found in less than half of adults with severe hypercholesterolemia. The characteristics of adults with severe hypercholesterolemia without pathogenic variant have been poorly described, and it remains unclear whether intensive preventive strategies should be recommended. In this study we compared the characteristics of adults with severe hypercholesterolemia with and without pathogenic variant for FH.
Methods
Between November 2020 and February 2022, we recruited individuals older than 16 years with a Dutch Lipid Clinic Network (DLCN) score ≥6 and genotyped LDLR, APOB and PCSK9. Participants were part of the multicenter CATCH study, testing the implementation of genetic cascade screening for FH in Switzerland. All genetic analyses were performed in a single central laboratory. Variants classified as likely pathogenic or pathogenic were interpreted as FH-causing. We also assessed socio-economic status, cardiovascular risk factors, lifestyle behavior, and use of lipid-lowering drugs.
Results
In total, 150 non-related adults with a DLCN score of ≥6 were included, out of whom 62 (41.3%) had genetically confirmed FH. Most variants were found in the LDLR gene (77%). Overall, 70% were using a lipid-lowering drug and 20% were current smokers. Compared to adults with genetically confirmed FH, those without pathogenic variants were older (57.6 vs 50.4 years old), had lower untreated LDL-cholesterol levels (p<0.001), higher triglyceride levels (p=0.032), higher BMI (p=0.014), and had more frequently hypertension (62.5% vs 36.1%). No socio-economic differences were observed. Although adherence to Mediterranean diet was higher among adults without pathogenic variant, they reached less frequently the recommended level of physical activity than adults with genetically confirmed FH (66.2% vs 82.1%). Xanthomas or xanthelasmas, but not corneal arcus, were more frequent among genetically confirmed FH (5.7% vs 20.3%).
Conclusions
Adults with severe hypercholesterolemia and without a pathogenic FH variant had less optimal control of cardiovascular risk factors than genetically confirmed FH. One fifth were smokers and one third of all patients included in this study were not taking any lipid-lowering drugs, regardless of the presence of a pathogenic variant.
Funding Acknowledgement
Type of funding sources: Foundation. Main funding source(s): Swiss Heart Foundation
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Experimental and modeling of tetracycline degradation in water in a flow-through enzymatic monolithic reactor. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:75896-75906. [PMID: 35665885 DOI: 10.1007/s11356-022-21204-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 05/27/2022] [Indexed: 06/15/2023]
Abstract
In this work, the laccase from Trametes versicolor was immobilized in highly porous silica monoliths (0.6-cm diameter, 0.5-cm length). These monoliths feature a unique homogeneous network of interconnected macropores (20 μm) with mesopores (20 nm) in the skeleton and a high specific surface area (330 m2/g). The enzymatic monoliths were applied to degrade tetracycline (TC) in model aqueous solutions (20 ppm). For this purpose, a tubular flow-through reactor (FTR) configuration with recycling was built. The TC degradation was improved with oxygen saturation, presence of degradation products, and recirculation rate. The TC depletion reaches 50% in the FTR and 90% in a stirred tank reactor (CSTR) using crushed monoliths. These results indicate the importance of maintaining a high co-substrate concentration near active sites. A model coupling mass transfers with a Michaelis-Menten kinetics was applied to simulate the TC degradation in real wastewaters at actual TC concentration (2.8 10-4 ppm). Simulation results show that industrial scale FTR reactor should be suitable to degrade 90% of TC in 5 h at a flow rate of 1 mL/min in a single passage flow configuration. Nevertheless, the process could certainly be further optimized in terms of laccase activity, oxygen supply near active sites, and contact time.
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Biocatalytic Elimination of Pharmaceutics Found in Water With Hierarchical Silica Monoliths in Continuous Flow. FRONTIERS IN CHEMICAL ENGINEERING 2022. [DOI: 10.3389/fceng.2022.823877] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Pharmaceutical products (PPs) are considered as emerging micropollutans in wastewaters, river and seawaters, and sediments. The biodegradation of PPs, such as ciprofloxacin, amoxicillin, sulfamethoxazole, and tetracycline by enzymes in aqueous solution was investigated. Laccase from Trametes versicolor was immobilized on silica monoliths with hierarchical meso-/macropores. Different methods of enzyme immobilization were experienced. The most efficient process was the enzyme covalent bonding through glutaraldehyde coupling on amino-grafted silica monoliths. Silica monoliths with different macropore and mesopore diameters were studied. The best support was the monolith featuring the largest macropore diameter (20 µm) leading to the highest permeability and the lowest pressure drop and the largest mesopore diameter (20 nm) ensuring high enzyme accessibility. The optimized enzymatic reactor (150 mg) was used for the degradation of a PP mixture (20 ppm each in 30 ml) in a continuous recycling configuration at a flow rate of 1 ml/min. The PP elimination efficiency after 24 h was as high as 100% for amoxicillin, 60% for sulfamethoxazole, 55% for tetracycline, and 30% for ciprofloxacin.
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Textural control of ionosilicas by Ionic Liquid templating. Phys Chem Chem Phys 2022; 24:21853-21862. [DOI: 10.1039/d2cp02524h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Due to their unique self-assembly properties, ionic liquids (ILs) are versatile soft templates for the formation of mesoporous materials. Here, we report the use of ionic liquids as soft templates...
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Implementation of cascade genetic screening for familial hypercholesterolemia: Design of the Swiss catch randomized controlled trial. Atherosclerosis 2021. [DOI: 10.1016/j.atherosclerosis.2021.06.562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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When graphene meets ionic liquids: a good match for the design of functional materials. NANOSCALE 2021; 13:2750-2779. [PMID: 33533392 DOI: 10.1039/d0nr06871c] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Graphene is an attractive material that is characterized by its exceptional properties (i.e. electrical, mechanical, thermal, optical, etc.), which have pushed researchers to attach high interest to its production and functionalization processes to meet applications in different fields (electronics, electromagnetics, composites, sensors, energy storage, etc.). The synthesis (bottom-up) of graphene remains long and laborious, at the same time expensive, and it is limited to the development of this material in low yield. Hence, the use of graphite as a starting material (top-down through exfoliation or oxidation) seems a promising and easy technique for producing a large quantity of graphene or graphene oxide (GO). On the one hand, GO has been extensively studied due to its ease of synthesis, processing and chemical post-functionalization. One the other hand, "pristine" graphene sheets, obtained through exfoliation, are limited in processability but present enhanced electronic properties. Both types of materials have been of great interest to design functional nanomaterials. Ionic liquids (ILs) are task-specific solvents that exhibit tunable physico-chemical properties. ILs have many advantages as compared with conventional solvents, such as high thermal and chemical stability, low volatility, excellent conductivity and inherent polarity. In the last decade, ILs have been widely employed for the preparation and stabilization of various nanomaterials. In particular, the combination of ILs and graphene, including GO and pristine graphene sheets, has been of growing interest for the preparation, processing and functionalization of hybrid nanomaterials. Understanding the structure and properties of the graphene/IL interface has been of considerable interest for a large panel of applications ranging from tribology to energy storage.
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Preoperative giant sacrococcygeal teratoma embolization in a newborn - A case report and a review. CIRUGIA PEDIATRICA : ORGANO OFICIAL DE LA SOCIEDAD ESPANOLA DE CIRUGIA PEDIATRICA 2020; 33:95-98. [PMID: 32250074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Sacrococcygeal teratoma (SCT) is the most frequent congenital germ cell tumor. Patients have a higher risk of perinatal complications and death, with bleeding and cardiac decompensation being the most common causes of neonatal mortality. This is the case of a 35-week preterm newborn with a large SCT diagnosed at ultrasound screening in the second trimester. Preoperative selective embolization of the middle sacral artery and total surgical resection were performed postnatally with minimal blood loss. The patient was discharged at 25 days of life with a normal physical examination. Selective embolization prior to giant SCT resection is feasible and appears as a safe and useful technique in the control of perioperative bleeding.
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Genomic DNA PCR analysis to assess xenograft development in mouse mammary gland. Biotechniques 2020; 68:219-222. [PMID: 31990209 DOI: 10.2144/btn-2019-0125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The mouse transplantation model remains the most relevant methodology to assess the functional capacities of mammary cells and is particularly appropriate for investigations regarding mammary stem cells, whatever the species studied. Following xenotransplantation in mice mammary fat pad, the development of the xenograft is commonly evaluated by immunohistology. Here, we present a simple and rapid method to control the species specificity of a xenograft based on genomic DNA PCR amplification. DNA is extracted from the fixed samples intended for histology, thus allowing the reuse of precious samples. Standard and digital droplet PCR (requiring low DNA quantities) methods have been used to make the present method suitable for the analysis of xenotransplanted samples.
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Self-Limited Grafting of Sub-Monolayers via Diels-Alder Reaction on Glassy Carbon Electrodes: An Electrochemical Insight. ACS OMEGA 2019; 4:20540-20546. [PMID: 31858038 PMCID: PMC6906774 DOI: 10.1021/acsomega.9b02391] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 11/14/2019] [Indexed: 06/01/2023]
Abstract
The grafting of molecular monolayers is critical for the functionalization of surfaces. In molecular electrochemistry, the surface modification of electrodes and the way molecules are attached to the electrode surface are highly critical to electron transfers and electrochemical reactions. In this paper, sub-monolayers were covalently grafted onto glassy carbon (GC) electrodes via Diels-Alder cycloaddition with two soluble dienophiles, that is, propargyl bromide and ethynyl ferrocene. Such an approach is clean (no by-product, no catalyst/additive) and occurs under mild conditions by heating at 50 °C in toluene for few hours. The as-modified electrodes were thoroughly characterized by FTIR, XPS, and cyclic voltammetry using both millimetric GC electrodes and ultra-microelectrodes. Cyclic voltammetry gave access to surface coverage and clearly evidenced the covalent grafting of sub-monolayers. The grafting of functional sub-monolayers via Diels-Alder cycloaddition could be easily extended to various functionalities and carbons to prepare electrochemical sensors or electrocatalytic surfaces.
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Rentabilité diagnostique du myélogramme systématique chez les patients de plus de 60 ans au diagnostic de purpura thrombopénique immunologique pour rechercher une cause secondaire. Rev Med Interne 2019. [DOI: 10.1016/j.revmed.2019.10.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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[Some stories of ordinary abuse during care]. LA REVUE DU PRATICIEN 2019; 69:1026-1027. [PMID: 32237631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
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Puberty is a critical window for the impact of diet on mammary gland development in the rabbit. Dev Dyn 2019; 248:948-960. [PMID: 31348557 PMCID: PMC6790954 DOI: 10.1002/dvdy.91] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 07/12/2019] [Accepted: 07/17/2019] [Indexed: 02/06/2023] Open
Abstract
Background Nutritional changes can affect future lactation efficiency. In a rabbit model, an obesogenic diet initiated before puberty and pursued throughout pregnancy enhances mammary differentiation, but when started during the neonatal period can cause abnormal mammary development in early pregnancy. The aim of this study was to investigate the impact of an unbalanced diet administered during the pubertal period only. Results Consuming an obesogenic diet at puberty did not affect either metabolic parameters or certain maternal reproductive parameters at the onset of adulthood. In contrast, at Day 8 of pregnancy, epithelial tissue showed a lower proliferation rate in obesogenic‐diet fed rabbits than in control‐diet fed rabbits. Wap and Cx26 genes, mammary epithelial cell differentiation markers, were upregulated although Wap protein level remained unchanged. However, the expression of genes involved in lipid metabolism and in alveolar formation was not modified. Conclusion Taken together, our results demonstrate that the consumption for 5 weeks of an obesogenic diet during the pubertal period initiates mammary structure modifications and affects mammary epithelial cell proliferation and differentiation. Our findings highlight the potentially important role played by unbalanced nutrition during critical early‐life windows in terms of regulating mammary epithelial cell differentiation and subsequent function in adulthood. Our results demonstrate that the consumption for five weeks of an obesogenic diet during the pubertal period initiates mammary structure modifications and affects mammary epithelial cell proliferation and differentiation. Our findings highlight the potentially important role played by unbalanced nutrition during critical early‐life windows in terms of regulating mammary epithelial cell differentiation and subsequent function in adulthood.
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Dehydration of Alginic Acid Cryogel by TiCl 4 vapor: Direct Access to Mesoporous TiO 2 @C Nanocomposites and Their Performance in Lithium-Ion Batteries. CHEMSUSCHEM 2019; 12:2660-2670. [PMID: 30950578 DOI: 10.1002/cssc.201900781] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 04/01/2019] [Indexed: 06/09/2023]
Abstract
A new strategy for the synthesis of mesoporous TiO2 @C nanocomposites through the direct mineralization of seaweed-derived alginic acid cryogel by TiCl4 through a solid/vapor reaction pathway is presented. In this synthesis, alginic acid cryogel can have multiple roles; i) mesoporous template, ii) carbon source, and iii) oxygen source for the TiO2 precursor, TiCl4 . The resulting TiO2 @alginic acid composite was transformed either into pure mesoporous TiO2 by calcination or into mesoporous TiO2 @C nanocomposites by pyrolysis. By comparing with a nonporous TiO2 @C composite, the importance of the mesopores on the performance of electrodes for lithium-ion batteries based on mesoporous TiO2 @C composite was clearly evidenced. In addition, the carbon matrix in the mesoporous TiO2 @C nanocomposite also showed electrochemical activity versus lithium ions, providing twice the capacity of pure mesoporous TiO2 or alginic acid-derived mesoporous carbon (A600). Given the simplicity and environmental friendliness of the process, the mesoporous TiO2 @C nanocomposite could satisfy the main prerequisites of green and sustainable chemistry while showing improved electrochemical performance as a negative electrode for lithium-ion batteries.
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Impact of exposure to diesel exhaust during pregnancy on mammary gland development and milk composition in the rabbit. PLoS One 2019; 14:e0212132. [PMID: 30763367 PMCID: PMC6375667 DOI: 10.1371/journal.pone.0212132] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 01/28/2019] [Indexed: 01/03/2023] Open
Abstract
Exposure to fine-particulate air pollution is a major global health concern because it is associated with reduced birth weight and an increased risk of cardiovascular disease. Here we have investigated the potential for exposure to diesel exhaust during pregnancy to influence mammary gland development and milk composition. Female rabbits were therefore exposed by nose-only inhalation to either diluted diesel exhaust fumes (1 mg/m3) or clean air for 2h/day, 5 days/week, from the 3rd to the 27th days of pregnancy. On Day 28 of pregnancy, mammary glands were collected from twelve females (six controls and six diesel-exposed) and assessed for morphological and functional alterations. Milk samples were collected from eighteen dams (nine controls and nine diesel-exposed) during early (days 2 to 4) and established (days 13 to 16) lactation to verify the composition of fatty acids and major proteins and leptin levels. The mammary alveolar lumina contained numerous fat globules, and stearoyl CoA reductase expression was higher in mammary epithelia from diesel exhaust-exposed rabbits, which together suggested increased mammary lipid biosynthesis. Gas chromatography analysis of the composition of milk fatty acids revealed a sharp rise in the total fatty acid content, mainly due to monounsaturated fatty acids. Liquid chromatography-mass spectrometry analysis of milk samples enabled identification and quantification of the main rabbit milk proteins and their main phosphorylated isoforms, and revealed important changes to individual casein and whey protein contents and to their most phosphorylated isoforms during early lactation. Taken together, these findings suggest that repeated daily exposure to diesel exhaust fumes during pregnancy at urban pollution levels can influence lipid metabolism in the mammary gland and the lipid and protein composition of milk. As milk may contribute to metabolic programming, such alterations affecting milk composition should be taken into account from a public health perspective.
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Metal-inorganic-organic core–shell material as efficient matrices for CO2 adsorption: Synthesis, properties and kinetic studies. J Taiwan Inst Chem Eng 2019. [DOI: 10.1016/j.jtice.2018.08.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Ethers as Oxygen Donor and Carbon Source in Non-hydrolytic Sol-Gel: One-Pot, Atom-Economic Synthesis of Mesoporous TiO 2 -Carbon Nanocomposites. Chemistry 2018; 24:4982-4990. [PMID: 29405463 DOI: 10.1002/chem.201800027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Indexed: 11/06/2022]
Abstract
Mesoporous TiO2 -carbon nanocomposites were synthesized using an original non-hydrolytic sol-gel (NHSG) route, based on the reaction of simple ethers (diisopropyl ether or tetrahydrofuran) with titanium tetrachloride. In this atom-economic, solvent-free process, the ether acts not only as an oxygen donor but also as the sole carbon source. Increasing the reaction temperature to 180 °C leads to the decomposition of the alkyl chloride by-product and to the formation of hydrocarbon polymers, which are converted to carbon by pyrolysis under argon. The carbon-TiO2 nanocomposites and their TiO2 counterparts (obtained by calcination) were characterized by nitrogen physisorption, XRD, solid state 13 C NMR and Raman spectroscopies, SEM, and TEM. The nanocomposites are mesoporous with surface areas of up to 75 m2 g-1 and pore sizes around 10 nm. They are composed of aggregated anatase nanocrystals coated by an amorphous carbon film. Playing on the nature of the ether and on the reaction temperature allows control over the carbon content in the nanocomposites. The nature of the ether also influences the size of the TiO2 crystallites and the morphology of the nanocomposite. To further characterize the carbon coating, the behavior of the carbon-TiO2 nanocomposites and bare TiO2 samples toward lithium insertion-deinsertion was investigated in half-cells. This simple NHSG approach should provide a general method for the synthesis of a wide range of carbon-metal oxide nanocomposites.
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Silver nanoparticle embedded copper oxide as an efficient core–shell for the catalytic reduction of 4-nitrophenol and antibacterial activity improvement. Dalton Trans 2018; 47:9143-9155. [DOI: 10.1039/c8dt02154f] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
A facile and eco-friendly method was developed to prepare a microporous CuO@Ag0 core–shell with high catalytic and antibacterial activities.
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Alginic acid aquagel as a template and carbon source in the synthesis of Li4Ti5O12/C nanocomposites for application as anodes in Li-ion batteries. RSC Adv 2018; 8:32558-32564. [PMID: 35547664 PMCID: PMC9086269 DOI: 10.1039/c8ra05928d] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 08/30/2018] [Indexed: 11/30/2022] Open
Abstract
We report here a simple process for the synthesis of Li4Ti5O12(LTO)/carbon nanocomposites by a one-pot method using an alginic acid aquagel as a template and carbon source, and lithium acetate and TiO2 nanoparticles as precursors to the LTO phase. The carbon content can be tuned by adjusting the relative amount of alginic acid. The obtained materials consist of nanosized primary particles of LTO (30 nm) forming micron-sized aggregates covered by well-dispersed carbon (from 3 to 19 wt%). The homogeneous dispersion of carbon over the particles improves the electrochemical performance of LTO electrodes such as rate capability (>95 mA h g−1 at 40C) and cycling performance (>98% of retention after 500 cycles at 5C), even with only 3% of carbon black additive in the electrode formulation. With a simple and easily up-scalable synthesis, the LTO/carbon nanocomposites of this study are promising candidates as anode materials for practical application in lithium-ion batteries. We report here a simple process for the synthesis of Li4Ti5O12(LTO)/carbon nanocomposites by a one-pot method using an alginic acid aquagel as a template and carbon source, and lithium acetate and TiO2 nanoparticles as precursors to the LTO phase.![]()
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Seuil de numération plaquettaire et autres facteurs de risque hémorragique au diagnostic de thrombopénie immunologique de l’adulte. Rev Med Interne 2017. [DOI: 10.1016/j.revmed.2017.10.329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Chemical modification of the cocoa shell surface using diazonium salts. J Colloid Interface Sci 2017; 494:92-97. [DOI: 10.1016/j.jcis.2017.01.069] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 01/19/2017] [Accepted: 01/20/2017] [Indexed: 10/20/2022]
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Abstract
The derivatization and covalent modification of biomass derived platform chemicals expand the biomass derived chemical spaces allowing for the preparation of new bioactive molecules and materials.
Biorefinery aims at the conversion of biomass and renewable feedstocks into fuels and platform chemicals, in analogy to conventional oil refinery. In the past years, the scientific community has defined a number of primary building blocks that can be obtained by direct biomass decomposition. However, the large potential of this “renewable chemical space” to contribute to the generation of value added bio-active compounds and materials still remains unexplored. In general, biomass derived building blocks feature a diverse range of chemical functionalities. In order to be integrated into value-added compounds, they require additional functionalization and/or covalent modification thereby generating secondary building blocks. The latter can be thus regarded as functional components of bio-active molecules or materials and represent an expansion of the renewable chemical space. This perspective highlights the most recent developments and opportunities for the synthesis of secondary biomass derived building blocks and their application to the preparation of value added products.
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A wireless system with stimulation and recording capabilities for interfacing peripheral nerves in rodents. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2017; 2016:4439-4442. [PMID: 28269263 DOI: 10.1109/embc.2016.7591712] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Considerable progress has been made in the last decade in implantable bioelectronic neurosystems. Yet most neural implants are used in acute and tethered experimental conditions. Here, we present a preliminary prototype of a multichannel system for simultaneous peripheral nerve stimulation and neural recording. The system comprises miniaturized electronics with a total volume of less then 1.4cm3 including a 3.7V battery which is expected to last for 94 days of standby operation or 18 hours of continuous recording and stimulation. Data read-out and device configuration are wireless. Visceral nerves in rodents are interfaced with compliant extraneural electrodes. The 100×350μm2 electrodes display a low impedance (1.8kn at 1kHz) with a PEDOT:PSS coating. We validated the prototype in acute experiments by applying electrical stimulation to the aortic depressor nerve (ADN), resulting in effective and reproducible decrease in blood pressure and heart rate. The combination of miniaturized electronics and flexible electrodes makes the presented system a versatile platform for future implantable devices interfacing small peripheral nerves and potentially enables new applications in the field of neuroscience.
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Intérêt d’initier la corticothérapie à dose conventionnelle par méthylprednisolone intraveineuse dans le purpura thrombopénique immunologique nouvellement diagnostiqué de l’adulte. Rev Med Interne 2016. [DOI: 10.1016/j.revmed.2016.10.131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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27
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28
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[The pathway approach and the coordination of care]. SOINS; LA REVUE DE REFERENCE INFIRMIERE 2016; 61:50-52. [PMID: 27338692 DOI: 10.1016/j.soin.2016.04.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The pathway approach is promoted by health authorities but is still limited by highly technical professional practices and partitioned organisations. Effective coordination requires professionals to put it into practice and the authorities in charge of delivering healthcare to allow it. This evolution must also be combined with closer collaboration with the patient.
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Multiwalled Carbon Nanotube/Cellulose Composite: From Aqueous Dispersions to Pickering Emulsions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:3907-3916. [PMID: 27052957 DOI: 10.1021/acs.langmuir.6b00380] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A mild and simple way to prepare stable aqueous colloidal suspensions of composite particles made of a cellulosic material (Sigmacell cellulose) and multiwalled carbon nanotubes (MWCNTs) is reported. These suspensions can be dried and redispersed in water at pH 10.5. Starting with rather crude initial materials, commercial Sigmacell cellulose and MWCNTs, a significant fraction of composite dispersed in water could be obtained. The solid composites and their colloidal suspensions were characterized by electronic microscopy, thermal analyses, FTIR and Raman spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and light scattering. The composite particles consist of tenuous aggregates of CNTs and cellulose, several hundred nanometers large, and are composed of 55 wt % cellulose and 45 wt % CNTs. Such particles were shown to stabilize cyclohexane-in-water emulsions. The adsorption and the elasticity of the layer they form at interface were characterized by the pendant drop method. The stability of the oil-in-water emulsions was attributed to the formation of an elastic network of composite particles at interface. Cyclohexane droplet diameters could be tuned from 20 to 100 μm by adjusting the concentration of composite particles. This behavior was attributed to the limited coalescence phenomenon, just as expected for Pickering emulsions. Interestingly, cyclohexane droplets were stable over time and sustained pH modifications over a wide range, although acidic pH induced accelerated creaming. This study points out the possibility of combining crude cellulose and MWCNTs through a simple process to obtain colloidal systems of interest for the design of functional conductive materials.
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Differences during the first lactation between cows cloned by somatic cell nuclear transfer and noncloned cows. J Dairy Sci 2016; 99:4778-4794. [PMID: 27016834 DOI: 10.3168/jds.2015-10532] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 02/08/2016] [Indexed: 01/06/2023]
Abstract
Lactation performance is dependent on both the genetic characteristics and the environmental conditions surrounding lactating cows. However, individual variations can still be observed within a given breed under similar environmental conditions. The role of the environment between birth and lactation could be better appreciated in cloned cows, which are presumed to be genetically identical, but differences in lactation performance between cloned and noncloned cows first need to be clearly evaluated. Conflicting results have been described in the literature, so our aim was to clarify this situation. Nine cloned Prim' Holstein cows were produced by the transfer of nuclei from a single fibroblast cell line after cell fusion with enucleated oocytes. The cloned cows and 9 noncloned counterparts were raised under similar conditions. Milk production and composition were recorded monthly from calving until 200d in milk. At 67d in milk, biopsies were sampled from the rear quarter of the udder, their mammary epithelial cell content was evaluated, and mammary cell renewal, RNA, and DNA were then analyzed in relevant samples. The results showed that milk production did not differ significantly between cloned and noncloned cows, but milk protein and fat contents were less variable in cloned cows. Furthermore, milk fat yield and contents were lower in cloned cows during early lactation. At around 67 DIM, milk fat and protein yields, as well as milk fat, protein, and lactose contents, were also lower in cloned cows. These lower yields could be linked to the higher apoptotic rate observed in cloned cows. Apoptosis is triggered by insulin-like factor growth binding protein 5 (IGFBP5) and plasminogen activator inhibitor (PAI), which both interact with CSN1S2. During our experiments, CSN1S2 transcript levels were lower in the mammary gland of cloned cows. The mammary cell apoptotic rate observed in cloned cows may have been related to the higher levels of DNA (cytosine-5-)-methyltransferase 1 (DNMT1) transcripts, coding for products that maintain the epigenetic status of cells. We conclude, therefore, that milk production in cloned cows differs slightly from that of noncloned cows. These differences may be due, in part, to a higher incidence of subclinical mastitis. They were associated with differences in cell apoptosis and linked to variations in DNMT1 mRNA. However, milk protein and fat contents were more similar among cloned cows than among noncloned cows.
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31
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Nanocomposites with both structural and porous hierarchy synthesized from Pickering emulsions. NEW J CHEM 2016. [DOI: 10.1039/c5nj03248b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Templating polycondensation of furfural and phloroglucinol by O/W emulsions stabilized by CNT-carboxymethylcellulose composite particles allowed preparing conductive and magnetic microcapsules.
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32
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Hierarchical porous silica monoliths: A novel class of microreactors for process intensification in catalysis and adsorption. CR CHIM 2016. [DOI: 10.1016/j.crci.2015.05.017] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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33
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Épidémiologie clinique et traitement de première ligne dans la thrombopénie immunologique. Résultats du registre CARMEN. Rev Med Interne 2015. [DOI: 10.1016/j.revmed.2015.10.337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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34
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Incidence des effets indésirables des traitements médicamenteux de la thrombopénie immunologique de l’adulte. Résultats du registre CARMEN. Rev Med Interne 2015. [DOI: 10.1016/j.revmed.2015.10.295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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35
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Prescription et rentabilité diagnostique du bilan paraclinique au diagnostic de thrombopénie immunologique. Résultats du registre CARMEN. Rev Med Interne 2015. [DOI: 10.1016/j.revmed.2015.03.285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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36
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[The user, a stakeholder in the functioning of the hospital]. SOINS; LA REVUE DE REFERENCE INFIRMIERE 2015; 60:40-42. [PMID: 26146323 DOI: 10.1016/j.soin.2015.04.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The French commission for relations with users and the quality of patient management (CruqPC) is a body which favours, in hospitals, the joint perspective of medical staff, nurses, administrative representatives and users regarding issues relating to the reception of users and the quality and safety of care. Its functioning is however disparate. Its place and its missions need to evolve.
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[INFORMATION ABOUT HOSPITALS AND THE ORGANISATION OF THE HEALTHCARE SYSTEM: EVALUATION OR CLASSIFICATION? THE USERS' POINT OF VIEW]. JOURNAL INTERNATIONAL DE BIOETHIQUE ET D'ETHIQUE DES SCIENCES 2015; 26:91-104. [PMID: 26606771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Until recently users felt that the French healthcare system was the best in the world and consequently all of the actors, structures and organisations were of a similar level of excellence and competence. Patients were often directed by their general practitioner or by the opinion of their friends and family. This feeling of homogenity of the quality of the hospitals or healthcare professionals has disappeared. Nowadays users want to have information which is useful for them and allows them to find their way in an organisation of healthcare that is very complex, and therefore a source of inequality. This informaion may come from institutional sites, league tables in newspapers or Internet sites. But, if it is to be useful, this information must be accessible and understandable by all, both in form and content. This is not always the case. It is in the interest of the healthcare system to be as transparent as possible, so it must resolutely go in this direction.
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Abstract
Carbon-based structures are the most versatile materials used in the modern nanotechnology. Therefore there is a need to develop increasingly more sustainable variants of carbon materials.
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39
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Synthesis of robust hierarchically porous zirconium phosphate monolith for efficient ion adsorption. NEW J CHEM 2015. [DOI: 10.1039/c4nj01749h] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hierarchically porous zirconium phosphate monoliths were synthesized and fabricated into a continuous flow setup for toxic metal ion adsorption.
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DNA methylation and transcription in a distal region upstream from the bovine AlphaS1 casein gene after once or twice daily milking. PLoS One 2014; 9:e111556. [PMID: 25369064 PMCID: PMC4219721 DOI: 10.1371/journal.pone.0111556] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 10/02/2014] [Indexed: 12/31/2022] Open
Abstract
Once daily milking (ODM) induces a reduction in milk production when compared to twice daily milking (TDM). Unilateral ODM of one udder half and TDM of the other half, enables the study of underlying mechanisms independently of inter-individual variability (same genetic background) and of environmental factors. Our results show that in first-calf heifers three CpG, located 10 kb upstream from the CSN1S1 gene were methylated to 33, 34 and 28%, respectively, after TDM but these levels were higher after ODM, 38, 38 and 33%, respectively. These methylation levels were much lower than those observed in the mammary gland during pregnancy (57, 59 and 50%, respectively) or in the liver (74, 78 and 61%, respectively). The methylation level of a fourth CpG (CpG4), located close by (29% during TDM) was not altered after ODM. CpG4 methylation reached 39.7% and 59.5%, during pregnancy or in the liver, respectively. CpG4 is located within a weak STAT5 binding element, arranged in tandem with a second high affinity STAT5 element. STAT5 binding is only marginally modulated by CpG4 methylation, but it may be altered by the methylation levels of the three other CpG nearby. Our results therefore shed light on mechanisms that help to explain how milk production is almost, but not fully, restored when TDM is resumed (15.1±0.2 kg/day instead of 16.2±0.2 kg/day, p<0.01). The STAT5 elements are 100 bp away from a region transcribed in the antisense orientation, in the mammary gland during lactation, but not during pregnancy or in other reproductive organs (ovary or testes). We now need to clarify whether the transcription of this novel RNA is a consequence of STAT5 interacting with the CSN1S1 distal region, or whether it plays a role in the chromatin structure of this region.
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Always look on the "light" side of life: sustainable carbon aerogels. CHEMSUSCHEM 2014; 7:670-689. [PMID: 24420578 DOI: 10.1002/cssc.201300961] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Indexed: 06/03/2023]
Abstract
The production of carbon aerogels based on the conversion of inexpensive and abundant precursors using environmentally friendly processes is a highly attractive subject in materials chemistry today. This article reviews the latest developments regarding the rapidly developing field of carbonaceous aerogels prepared from biomass and biomass-derived precursors, highlighting exciting and innovative approaches to green, sustainable nanomaterial synthesis. A review of the state-of-the-art technologies will be provided with a specific focus on two complimentary synthetic approaches developed upon the principles of green chemistry. These carbonaceous aerogel synthesis strategies, namely the Starbon and carbogel approaches, can be regarded as "top-down" and "bottom-up" strategies, respectively. The structural properties can be easily tailored by controlling synthetic parameters such as the precursor selection and concentration, the drying technique employed and post-synthesis temperature annealing. In addition to these parameters, the behavior of these sustainable carbon aerogel platforms in a variety of environmental and energy-related applications will also be discussed, including water remediation and fuel cell chemistry (i.e., the oxygen reduction reaction). This Review reveals the fascinating variety of highly porous, versatile, nanostructured, and functional carbon-based aerogels accessible through the highlighted sustainable synthetic platforms.
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Abstract
An original approach based on the hydrothermal carbonization of nitrogen-containing biomass derivatives within the continuous phase of a direct concentrated emulsion is reported for the synthesis of nitrogen-doped microcellular carbon monoliths. These biosourced foams show promising performances as intrinsic electrocatalysts in the oxygen reduction reaction. Preliminary catalytic properties of powdered versus monolithic samples are discussed and suggest interesting prospects for their introduction within electrochemical devices.
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P061 Conception d’un programme d’éducation thérapeutique destiné aux adolescents atteints d’hypercholestérolémie familiale. NUTR CLIN METAB 2013. [DOI: 10.1016/s0985-0562(13)70393-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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44
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Selecting for function: solution synthesis of magnetic nanopropellers. NANO LETTERS 2013; 13:5373-5378. [PMID: 24127909 PMCID: PMC3885197 DOI: 10.1021/nl402897x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 09/12/2013] [Indexed: 05/30/2023]
Abstract
We show that we can select magnetically steerable nanopropellers from a set of carbon coated aggregates of magnetic nanoparticles using weak homogeneous rotating magnetic fields. The carbon coating can be functionalized, enabling a wide range of applications. Despite their arbitrary shape, all nanostructures propel parallel to the vector of rotation of the magnetic field. We use a simple theoretical model to find experimental conditions to select nanopropellers which are predominantly smaller than previously published ones.
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Prévention et éducation dans les domaines du porter soins et secours par un nouveau modèle d’éducation à la santé familiale. Rev Epidemiol Sante Publique 2013. [DOI: 10.1016/j.respe.2013.07.306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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46
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Reproductive Response in Offspring Male Rats Exposed to Prenatal Stress and to Early Postnatal Stimulation. INT J MORPHOL 2013. [DOI: 10.4067/s0717-95022013000200065] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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47
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Emulsion-templated macroporous carbons synthesized by hydrothermal carbonization and their application for the enzymatic oxidation of glucose. CHEMSUSCHEM 2013; 6:701-710. [PMID: 23495045 DOI: 10.1002/cssc.201200692] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Indexed: 06/01/2023]
Abstract
Carbon-based monoliths have been designed using a simple synthetic pathway based on using high internal phase emulsion (HIPE) as a soft template to confine the polymerization and hydrothermal carbonization of saccharide derivatives (furfural) and phenolic compounds (phloroglucinol). Monosaccharides can be isolated from the cellulosic fraction of lignocellulosic biomass and phloroglucinol can be extracted from the bark of fruit trees; however, this approach constitutes an interesting sustainable synthetic route. The macroscopic characteristics can be easily modulated; a high macroporosity and total pore volume of up to 98 % and 18 cm(3)g(-1) have been obtained, respectively. After further thermal treatment under inert atmosphere, the as-synthesized macroporous carbonized HIPEs (carbo-HIPEs) have shaping capabilities relating to interesting mechanical properties as well as a high electrical conductivity of up to 300 Sm(-1) . These conductive foams exhibit a hierarchical structure associated with the presence of both meso- and micropores that exhibit specific Brunauer-Emmett-Teller (BET) surface areas and DFT total pore volumes up to 730 m(2)g(-1) and 0.313 cm(3)g(-1) , respectively. Because of their attractive structural characteristics and intrinsic properties, these macroporous monoliths have been incorporated as a proof of principle within electrochemical devices as modified thin carbon disc electrodes. A promising two-fold improvement in the catalytic current is observed for the electrooxidation of glucose after the immobilization of a glucose oxidase-based biocatalytic mixture onto the carbo-HIPE electrodes compared to that observed if using commercial glassy carbon electrodes.
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Hydrothermal carbons from hemicellulose-derived aqueous hydrolysis products as electrode materials for supercapacitors. CHEMSUSCHEM 2013; 6:374-382. [PMID: 23319452 DOI: 10.1002/cssc.201200817] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Indexed: 06/01/2023]
Abstract
Acid pretreatment of lignocellulosic biomass, required for bioethanol production, generates large amounts of by-products, such as lignin and hydrolyzed hemicellulose fractions, which have found so far very limited applications. In this work, we demonstrate how the recovered hemicellulose hydrolysis products can be effectively utilized as a precursor for the synthesis of functional carbon materials through hydrothermal carbonization (HTC). The morphology and chemical structure of the synthesized HTC carbons are thoroughly characterized to highlight their similarities with glucose-derived HTC carbons. Furthermore, two routes for introducing porosity within the HTC carbon structure are presented: i) silica nanoparticle hard-templating, which is shown to be a viable method for the synthesis of carbonaceous hollow spheres; and ii) KOH chemical activation. The synthesized activated carbons (ACs) show an extremely high porosity (pore volume≈1.0 cm(3) g(-1)) mostly composed of micropores (90 % of total pore volume). Because of their favorable textural properties, the ACs are further tested as electrodes for supercapacitors, yielding very promising results (300 F g(-1) at 250 mA g(-1)) and confirming the high suitability of KOH-activated HTC carbons derived from spruce and corncob hydrolysis products as materials for electric double layer supercapacitors.
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49
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Chiral supported ionic liquid phase (CSILP) catalysts for greener asymmetric hydrogenation processes. Catal Today 2013. [DOI: 10.1016/j.cattod.2012.06.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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50
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Hydrothermal synthesis of highly porous carbon monoliths from carbohydrates and phloroglucinol. RSC Adv 2013. [DOI: 10.1039/c3ra41419a] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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