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Ju Z, Brosse N, Hoppe S, Wang Z, Ziegler-Devin I, Zhang H, Shu B. Thermal and mechanical properties of polyethylene glycol (PEG)-modified lignin/polylactic acid (PLA) biocomposites. Int J Biol Macromol 2024; 262:129997. [PMID: 38340934 DOI: 10.1016/j.ijbiomac.2024.129997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 01/22/2024] [Accepted: 02/04/2024] [Indexed: 02/12/2024]
Abstract
In this study, a method was proposed to prepare biocomposites from polylactic acid (PLA) and polyethylene glycol (PEG)-modified lignin using twin-screw extrusion process. The structure of PEG-modified lignin was studied by Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatographic (GPC) analysis. The effects of different contents of soda lignin and PEG-modified lignin on PLA composites were studied by tensile test, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), dynamic mechanical analysis (DMA) and degradation analysis. The experimental results showed that the addition of PEG-modified lignin enhanced the heat resistance of PLA composite. PLA could be combined with up to 30 % PEG-modified lignin, with no significant reduction in tensile strength properties. Compared with PLA-L30, the tensile stress and elongation at break of PLA-PL30 were increased by 26.4 % and 78.9 %, respectively. This approach provided a new way to produce high-performance lignin based-PLA composites and had certain industrial application value.
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Affiliation(s)
- Zehui Ju
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, PR China; Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, PR China; Université de Lorraine - INRAE - LERMAB - GP4W, F 54000 Nancy, France.
| | - Nicolas Brosse
- Université de Lorraine - INRAE - LERMAB - GP4W, F 54000 Nancy, France.
| | - Sandrine Hoppe
- Université de Lorraine - CNRS - LRGP, F 54000 Nancy, France
| | - Zhiqiang Wang
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, PR China; Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, PR China
| | | | - Haiyang Zhang
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, PR China
| | - Biqing Shu
- College of Civil Engineering, Yangzhou Polytechnic Institute, Yangzhou 225127, PR China
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Jin H, Zhang Y, Wu G, Yang J, Li N. Optimization via response surface methodology of the synthesis of a dust suppressant and its performance characterization for use in open cut coal mines. J Environ Sci (China) 2022; 121:211-223. [PMID: 35654511 DOI: 10.1016/j.jes.2021.12.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 10/19/2021] [Accepted: 12/09/2021] [Indexed: 06/15/2023]
Abstract
To relieve dust pollution in open cut coal mines and reduce the hazards of coal dust pollution to the environment and workers we optimized the synthesis of a dust suppressant by graft copolymerization of environmentally friendly soy protein isolate with methyl methacrylate. This dust suppressant could effectively control dust pollution in open cut coal mines. The optimized conditions for graft copolymerization in this case were determined by a response surface experiment designed with Design-Expert 10 software. Characterization by scanning electron microscopy showed a significant morphology change of the dust suppressant and the generation of a rigid and dense layer on its surface after interacting with coal dust. The layer exhibited good bonding and dust suppression performance. The analysis with Fourier-transform infrared spectroscopy revealed the appearance of new absorption peaks near 1300, 1072, and 1631 cm-1, demonstrating effective graft copolymerization. The proposed dust suppressant exhibited excellent wind erosion resistance, with a resistance that exceeded 90% at a wind speed of 6.5 m/sec. The successful graft copolymerization and effective bonding and curing of the dust suppressant on coal dust were experimentally verified. This is of great significance to the control of coal dust pollution.
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Affiliation(s)
- Hu Jin
- College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China; College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China; Qingdao Intelligent Control Engineering Center for Production Safety Fire Accident, Qingdao 266590, China
| | - Yansong Zhang
- College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China; College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China; Qingdao Intelligent Control Engineering Center for Production Safety Fire Accident, Qingdao 266590, China.
| | - Guangan Wu
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China
| | - Junjie Yang
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China
| | - Nan Li
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China
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Sarfehnia A, Ruschin M, Chugh B, Yeboah C, Becker N, Cho YB, Lee Y. Performance characterization of an integrated cone-beam CT system for dedicated gamma radiosurgery. Med Phys 2018; 45:4179-4190. [PMID: 29959780 DOI: 10.1002/mp.13073] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 05/16/2018] [Accepted: 06/04/2018] [Indexed: 11/10/2022] Open
Abstract
PURPOSE This work describes the performance characterization of a cone-beam CT-guided radiosurgery device, the Gamma Knife® Icon™. METHODS The performance tests have been categorized into: (a) image quality and mechanical integrity; (b) image coregistration fidelity; (c) adaptive treatment delivery quality; (d) high definition motion management performance characterization; (e) software communication performance testing of the integrated cone-beam CT (CBCT) system. RESULTS All image quality performance characterization satisfied or exceeded manufacturer specifications. The image quality and mechanical stability of the CBCT system over a 3-month period was within tolerance with negligible (<0.1°) detector tilt angle. The CBCT definition of the stereotactic space had a measured average discrepancy of 0.15-0.16 mm in x, y, and z directions. On average, the high definition motion management system performance was within 0.05 mm with a residual offset of 0.15 mm when large displacements in a given direction were taken. The adaptive treatment delivery component as measured with CBCT coregistration of daily setups against reference setup images was accurate to within 0.2°. Comprehensive end-to-end testing showed a total uncertainty of better than 0.2 mm in positioning and 0.4% in dosimetry for treatment of centrally located lesions. CONCLUSIONS A set of system performance characterization tests spanning all aspects of the Gamma Knife Icon are presented. Overall, the system performance was in line with manufacturer specifications.
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Affiliation(s)
- Arman Sarfehnia
- Department of Radiation Oncology, University of Toronto, 150 College St., Toronto, ON, M5S-3E2, Canada
- Department of Medical Physics, Odette Cancer Centre, Sunnybrook Health Sciences Centre, 2075 Bayview Ave., Toronto, ON, M4N-3M5, Canada
| | - Mark Ruschin
- Department of Radiation Oncology, University of Toronto, 150 College St., Toronto, ON, M5S-3E2, Canada
- Department of Medical Physics, Odette Cancer Centre, Sunnybrook Health Sciences Centre, 2075 Bayview Ave., Toronto, ON, M4N-3M5, Canada
| | - Brige Chugh
- Department of Radiation Oncology, University of Toronto, 150 College St., Toronto, ON, M5S-3E2, Canada
- Department of Medical Physics, Odette Cancer Centre, Sunnybrook Health Sciences Centre, 2075 Bayview Ave., Toronto, ON, M4N-3M5, Canada
| | - Collins Yeboah
- Department of Radiation Oncology, University of Toronto, 150 College St., Toronto, ON, M5S-3E2, Canada
- Department of Medical Physics, Odette Cancer Centre, Sunnybrook Health Sciences Centre, 2075 Bayview Ave., Toronto, ON, M4N-3M5, Canada
| | - Nathan Becker
- Department of Radiation Oncology, University of Toronto, 150 College St., Toronto, ON, M5S-3E2, Canada
- Department of Medical Physics, Princess Margaret Cancer Centre, 610 University Ave., Toronto, ON, M5G-2M9, Canada
| | - Young-Bin Cho
- Department of Radiation Oncology, University of Toronto, 150 College St., Toronto, ON, M5S-3E2, Canada
- Department of Medical Physics, Princess Margaret Cancer Centre, 610 University Ave., Toronto, ON, M5G-2M9, Canada
| | - Young Lee
- Department of Radiation Oncology, University of Toronto, 150 College St., Toronto, ON, M5S-3E2, Canada
- Department of Medical Physics, Odette Cancer Centre, Sunnybrook Health Sciences Centre, 2075 Bayview Ave., Toronto, ON, M4N-3M5, Canada
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Reena P, Dayananda S, Pai R, Jamema SV, Gupta T, Deepak D, Rajeev S. Performance characterization of siemens primus linear accelerator under small monitor unit and small segments for the implementation of step-and-shoot intensity-modulated radiotherapy. J Med Phys 2011; 31:269-74. [PMID: 21206643 PMCID: PMC3004102 DOI: 10.4103/0971-6203.29197] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2006] [Accepted: 09/02/2006] [Indexed: 11/24/2022] Open
Abstract
Implementation of step-and-shoot intensity-modulated radiotherapy (IMRT) needs careful understanding of the accelerator start-up characteristic to ensure accurate and precise delivery of radiation dose to patient. The dosimetric characteristic of a Siemens Primus linear accelerator (LA) which delivers 6 and 18 MV x-rays at the dose rate of 300 and 500 monitor unit (MU) per minutes (min) respectively was studied under the condition of small MU ranging from 1 to 100. Dose monitor linearity was studied at different dose calibration parameter (D1_C0) by measuring ionization at 10 cm depth in a solid water phantom using a 0.6 cc ionization chamber. Monitor unit stability was studied from different intensity modulated (IM) groups comprising various combinations of MU per field and number of fields. Stability of beam flatness and symmetry was investigated under normal and IMRT mode for 20×20 cm2 field under small MU using a 2D Profiler kept isocentrically at 5 cm depth. Inter segment response was investigated form 1 to 10 MU by measuring the dose per MU from various IM groups, each consisting of four segments with inter-segment separation of 2 cm. In the range 1-4 MU, the dose linearity error was more than 5% (max −32% at 1 MU) for 6 MV x-rays at factory calibrated D1_C0 value of 6000. The dose linearity error was reduced to −10.95% at 1 MU, within −3% for 2 and 3 MU and ±1% for MU ≥4 when the D1_C0 was subsequently tuned at 4500. For 18 MV x-rays, the dose linearity error at factory calibrated D1_C0 value of 4400 was within ±1% for MU ≥3 with maximum of −13.5 observed at 1 MU. For both the beam energies and MU/field ≥4, the stability of monitor unit tested for different IM groups was within ±1% of the dose from the normal treatment field. This variation increases to −2.6% for 6 MV and −2.7% for 18 MV x-rays for 2 MU/field. No significant variation was observed in the stability of beam profile measured from normal and IMRT mode. The beam flatness was within 3% for 6 MV x-rays and more than 3% (Max 3.5%) for 18 MV x-rays at lesser irradiation time ≤3 MU. The beam stability improves with the increase in irradiation time. Both the beam energies show very good symmetry (≤2%) at all irradiation time. For all the three segment sizes studied, the nonlinearity was observed at smaller MU/segment in both the energies. When the MU/segment is ≥4, all segment size shows fairly linear relation with dose/MU. The smaller segment size shows larger nonlinearity at smaller MU/segment and become more linear at larger MU/segment. Based on our study, we conclude that the Primus LA from Siemens installed at our hospital is ideally suited for step-and-shoot IMRT preferably for radiation ON time ≥4MU per segment.
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Affiliation(s)
- P Reena
- Department of Radiation Oncology, ACTREC, TMC, Kharghar, New Mumbai, India
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