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Chuan Tan Y, Chun Zeng H. Self-templating synthesis of hollow spheres of MOFs and their derived nanostructures. Chem Commun (Camb) 2016; 52:11591-4. [DOI: 10.1039/c6cc05699g] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A facile one-pot aqueous synthetic approach is developed to prepare ZIF-67 hollow spheres under room conditions.
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Affiliation(s)
- Ying Chuan Tan
- Department of Chemical and Biomolecular Engineering
- Faculty of Engineering
- National University of Singapore
- Singapore 119260
| | - Hua Chun Zeng
- Department of Chemical and Biomolecular Engineering
- Faculty of Engineering
- National University of Singapore
- Singapore 119260
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Kämmer E, Dörfer T, Csáki A, Schumacher W, Da Costa Filho PA, Tarcea N, Fritzsche W, Rösch P, Schmitt M, Popp J. Evaluation of Colloids and Activation Agents for Determination of Melamine Using UV-SERS. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2012; 116:6083-6091. [PMID: 22428076 PMCID: PMC3304507 DOI: 10.1021/jp211863y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Revised: 02/10/2012] [Indexed: 05/27/2023]
Abstract
UV-SERS measurements offer a great potential for environmental or food (detection of food contaminats) analytics. Here, the UV-SERS enhancement potential of various kinds of metal colloids, such as Pd, Pt, Au, Ag, Au-Ag core-shell, and Ag-Au core-shell with different shapes and sizes, were studied using melamine as a test molecule. The influence of different activation (KF, KCl, KBr, K(2)SO(4)) agents onto the SERS activity of the nanomaterials was investigated, showing that the combination of a particular nanoparticle with a special activation agent is extremely crucial for the observed SERS enhancement. In particular, the size dependence of spherical nanoparticles of one particular metal on the activator has been exploited. By doing so, it could be shown that the SERS enhancement increases or decreases for increasing or decreasing size of a nanoparticle, respectively. Overall, the presented results demonstrate the necessity to adjust the nanoparticle size and the activation agent for different experiments in order to achieve the best possible UV-SERS results.
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Affiliation(s)
- Evelyn Kämmer
- Institute of Physical Chemistry
and Abbe Center of Photonics, Friedrich Schiller University, Helmholtzweg 4, D-07743 Jena, Germany
- Institute of Photonic
Technology, Albert-Einstein-Strasse 9, 07745 Jena, Germany
| | - Thomas Dörfer
- Institute of Physical Chemistry
and Abbe Center of Photonics, Friedrich Schiller University, Helmholtzweg 4, D-07743 Jena, Germany
- Institute of Photonic
Technology, Albert-Einstein-Strasse 9, 07745 Jena, Germany
| | - Andrea Csáki
- Institute of Photonic
Technology, Albert-Einstein-Strasse 9, 07745 Jena, Germany
| | - Wilm Schumacher
- Institute of Physical Chemistry
and Abbe Center of Photonics, Friedrich Schiller University, Helmholtzweg 4, D-07743 Jena, Germany
| | | | - Nicolae Tarcea
- Institute of Physical Chemistry
and Abbe Center of Photonics, Friedrich Schiller University, Helmholtzweg 4, D-07743 Jena, Germany
| | - Wolfgang Fritzsche
- Institute of Photonic
Technology, Albert-Einstein-Strasse 9, 07745 Jena, Germany
| | - Petra Rösch
- Institute of Physical Chemistry
and Abbe Center of Photonics, Friedrich Schiller University, Helmholtzweg 4, D-07743 Jena, Germany
| | - Michael Schmitt
- Institute of Physical Chemistry
and Abbe Center of Photonics, Friedrich Schiller University, Helmholtzweg 4, D-07743 Jena, Germany
| | - Jürgen Popp
- Institute of Physical Chemistry
and Abbe Center of Photonics, Friedrich Schiller University, Helmholtzweg 4, D-07743 Jena, Germany
- Institute of Photonic
Technology, Albert-Einstein-Strasse 9, 07745 Jena, Germany
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Hojo M, Ueda T, Ike M, Kobayashi M, Nakai H. UV–visible, 1H and 13C NMR spectroscopic studies on the interaction between protons or alkaline earth metal ions and the benzoate ion in acetonitrile. J Mol Liq 2009. [DOI: 10.1016/j.molliq.2008.06.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Hojo M, Nose A. Role of Solutes in the Hydrogen Bonding of Water-Ethanol Mixtures. BUNSEKI KAGAKU 2008. [DOI: 10.2116/bunsekikagaku.57.171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Masashi Hojo
- Department of Chemistry, Faculty of Science, Kochi University
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Abstract
The paper reviews ion aggregation in ionic solution in solvents of low and high permittivity. Although higher ion aggregates from 1:1 type electrolytes in low-pemittivity media (εr < 10) are widely accepted, only a few chemists have recognized the higher ion aggregation in the higher-permittivity media. However, we have clarified that the chemical interaction, such as coordination, can operate between simple anions and cations in nonaqueous solvents (20 < εr < 65) of low solvation ability. Acids (HA) and their conjugate base anions (A-) may react with each other to form homoconjugated species, such as A-(HA)2, in acetonitrile or benzonitrile (i.e., solvents possessing poor hydrogen-bonding donor and acceptor abilities). An analytical method of conductivity data for 1:1 electrolytes has been developed and successfully applied to very complicated systems, in which the ion pair (1:1), triple ions (2:1 and 1:2), and the quadrupole (2:2 association) are involved in a solution at the same time. After observing the direct reaction of some anions (e.g., Cl-) and cations (e.g., Li+) toward a certain species, we interpreted comprehensively the salt effects in chemical equilibria, based on distinct chemical interactions and not merely a vague term, "medium effect". The mechanism of salt effects on solvolysis reactions of the SN1 type in organic-aqueous mixed solvents has been elucidated. We discussed that a reaction manner similar to that in nonaqueous solution can take place even in some "aqueous" solution if the huge network of hydrogen-bonding of bulk water (the number of water, nw > ~108) is destroyed due to any spatial barriers (such as ions, molecules, surface) or elevated temperature.
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Nose A, Hojo M. Hydrogen bonding of water-ethanol in alcoholic beverages. J Biosci Bioeng 2006; 102:269-80. [PMID: 17116572 DOI: 10.1263/jbb.102.269] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2006] [Accepted: 05/26/2006] [Indexed: 11/17/2022]
Abstract
An alcoholic beverage is a type of water-ethanol solution with flavor and taste. The properties of the hydrogen bonding of water-ethanol in alcoholic beverages have not been clarified sufficiently. We investigated factors that could affect the hydrogen-bonding structure of water-ethanol on the basis of proton nuclear magnetic resonance (1H NMR) chemical shifts of the OH of water-ethanol and Raman OH stretching spectra. Not only acids (H+ and HA: undissociated acids) but also bases (OH- and A-: conjugate-base anions from weak acids) strengthened the hydrogen-bonding structure of water-ethanol. It was also demonstrated that the hydrogen bonding is strengthened by chemical components in alcoholic beverages (whiskey, Japanese sake, shochu). It can be suggested that hydrogen-bonding donors as well as acceptors in alcohol beverages, which exist as the initial components or are gained later on, should cause the tight association between water and ethanol molecules.
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Affiliation(s)
- Akira Nose
- Suigei Brewing Co., Ltd., 566 Nagahama, Kochi 781-0270, Japan.
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Hojo M, Ueda T, Daike C, Takezaki F, Furuya Y, Miyamoto K, Narutaki A, Kato R. Great Enhancement in the Oxidation Ability of Dilute Nitric Acid in Nanoscale Water-Droplets of Reverse Micelle Systems. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2006. [DOI: 10.1246/bcsj.79.1215] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Nose A, Myojin M, Hojo M, Ueda T, Okuda T. Proton nuclear magnetic resonance and Raman spectroscopic studies of Japanese sake, an alcoholic beverage. J Biosci Bioeng 2005; 99:493-501. [PMID: 16233822 DOI: 10.1263/jbb.99.493] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2004] [Accepted: 02/16/2005] [Indexed: 11/17/2022]
Abstract
The hydrogen-bonding property of water--ethanol in Japanese sake, a kind of brewage, was examined on the basis of both (1)H NMR chemical shifts of the OH of water--ethanol and the Raman OH stretching spectra. In 20% (v/v) EtOH-H(2)O solution, amino acids as well as organic acids caused low-field chemical shifts, i.e., the development of a hydrogen-bonding structure. Additional functional groups, apart from the essential amino- and carboxyl groups, in amino acids caused differences in their effects. The low-field chemical shifts caused by solutes were demonstrated under constant pH conditions maintained by sodium hydrogen citrate. Using both the measurement of (1)H NMR chemical shifts and Raman OH stretching spectra, the strength of the hydrogen bond of water--ethanol in Japanese sake products was found to be correlated with the total concentration of organic acids and amino acids. Glucose or saccharides should not have a strengthening effect on the hydrogen bond of water--ethanol. The effects of the main inorganic ions and amines were also discussed. It was concluded that chemical components originating from the starting material, rice, or products produced by microorganisms during the ethanol fermentation affect the hydrogen-bonding structure in Japanese sake.
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Affiliation(s)
- Akira Nose
- Graduate School of Science, Kochi University, 2-5-1 Akebono-cho, Kochi 780-8520, Japan
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Sun Y, Yang ZL, Zhang L, Zhou NF, Weng SF, Wu JG. The interaction of Co2+ ions and sodium deoxycholate micelles. J Mol Struct 2003. [DOI: 10.1016/s0022-2860(03)00297-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Hojo M, Ueda T, Yamasaki M, Inoue A, Tokita S, Yanagita M. 1H and13C NMR Detection of the Carbocations or Zwitterions from Rhodamine B Base, a Fluoran-Based Black Color Former, Trityl Benzoate, and Methoxy-Substituted Trityl Chlorides in the Presence of Alkali Metal or Alkaline Earth Metal Perchlorates in Acetonitrile Solution. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2002. [DOI: 10.1246/bcsj.75.1569] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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