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181.
Hendrik Voigt Aaron Rigoni Evgeniy Boltynjuk Mohammed Reda Chellali Bonnie Tyler Harald Rösner Sergiy Divinski Horst Hahn Gerhard Wilde 《Advanced functional materials》2023,33(44):2302386
Comprehensive analyses of the atomic structure using advanced analytical transmission electron microscopy-based methods combined with atom probe tomography confirm the presence of distinct glass–glass interfaces in a columnar Cu-Zr nanoglass synthesized by magnetron sputtering. These analyses provide first-time in-depth characterization of sputtered film nanoglasses and indicate that glass–glass interfaces indeed present an amorphous phase with reduced mass density as compared to the neighboring amorphous regions. Moreover, dedicated analyses of the diffusion kinetics by time-of-flight secondary ion mass spectroscopy (ToF SIMS) prove significantly enhanced diffusivity, suggesting fast transport along the low density glass–glass interfaces. The present results further indicate that sputter deposition is a feasible technique for reliable production of nanoglasses and that some of the concepts proposed for this new class of glassy materials are applicable. 相似文献
182.
Material processing adopting microwave heating has emerged as an alternative tool owing to faster processing, a cleaner environment, and several other advantages. This review provides a summary of recent reports of microwave synthesis of materials. This study reviews the use of microwave energy for application in several material processing technologies apart from food processing. A special emphasis has been made in the processing of glass adopting microwave energy. Melting of glass comprising SiO2, P2O5, B2O3 as the main building block has been discussed. It has been revealed that silica, a microwave transparent material as reported earlier, can be heated under microwave heating directly. Microwave absorption of raw materials and different glass system has been discussed. Dielectric properties, particularly loss tangent or loss factor, are presented for some glass composition. Less evaporation of ingredient and low contamination from the crucible wall are noticed during glass melting using microwave heating. Enhanced iron redox ratio (Fe+2/∑Fe) in microwave processing may be considered an advantage in the preparation of heat absorbing filter glass. Small-scale glass melting using the microwave heating has a significant impact on energy and time saving. However, the challenges associated with the upscaling glass melting with microwave heating and future scope have been talked about. 相似文献
183.
Chutima Wiranidchapong Waraporn Kieongarm Chittima Managit Watoo Phrompittayarat 《Drug development and industrial pharmacy》2016,42(4):644-653
AbstractThe objective of this study was to investigate thermal and mechanical properties as well as in vitro drug release of Eudragit® RL (ERL) film using chlorpheniramine maleate (CPM) as either active pharmaceutical ingredient or non-traditional plasticizer. Differential scanning calorimeter was used to measure the glass transition temperature (Tg) of 0–100% w/w CPM in ERL physical mixture. Instron testing machine was used to investigate Young’s modulus, tensile stress and tensile strain (%) of ERL film containing 20–60% w/w CPM. Finally, a Franz diffusion cell was used to study drug release from ERL films obtained from four formulations, i.e. CRHP0/0, CRHP0/5, CRHP2/0 and CRHP2/5. The Tg of ERL was decreased when the weight percentage of CPM increased. The reduction of the Tg could be described by Kwei equation, indicating the interaction between CPM and ERL. Modulus and tensile stress decreased whereas tensile strain (%) increased when weight percentage of CPM increased. The change of mechanical properties was associated with the reduction of the Tg when weight percentage of CPM increased. ERL films obtained from four formulations could release the drug in no less than 10?h. Cumulative amount of drug release per unit area of ERL film containing only CPM (CRHP0/0) was lower than those obtained from the formulations containing traditional plasticizer (CRHP0/5), surfactant (CRHP2/0) or both of them (CRHP2/5). The increase of drug release was a result of the increase of drug permeability through ERL film and drug solubility based on traditional plasticizer and surfactant, respectively. 相似文献
184.
采用分子动力学(MD)模拟方法研究了环氧树脂4,4’-二氨基二苯甲烷四缩水甘油醚(TGDDM)与固化剂4,4’-二氨基二苯砜(DDS)交联过程中结构与能量的变化情况,预测了交联环氧树脂的玻璃化转变温度(Tg)、体积热膨胀系数和力学性能。研究结果表明,交联反应使得TGDDM/DDS体系密度增大,结构堆积更加紧密,范德华力和静电作用力增大,总能量减小,反应过程放热,通过温度-比体积曲线得到了交联体系的Tg约为527.9K,与实验值538.9K较为吻合,交联显著增强了材料的力学性能,而高温环境会引起树脂力学性能的下降,通过径向分布函数g(r)揭示了温度对交联环氧树脂结构的影响规律。 相似文献
185.
分别以马来酸酐、KH550、KH560和KH570为偶联剂对玻璃纤维进行预处理,再与淀粉、聚乳酸(PLA)复合,通过熔融挤出法制备玻璃纤维增强淀粉/PLA复合材料。研究了偶联剂种类对玻璃纤维增强复合材料熔融指数、力学性能、热性能和熔融流变性能的影响。实验发现马来酸酐、KH550、KH570、KH560处理玻璃纤维增强淀粉/PLA复合材料的熔融指数和力学性能都依次增大,表明KH560处理玻璃纤维增强淀粉/PLA复合材料的界面黏结作用最强。对热性能进行表征发现,马来酸酐、KH550、KH570、KH560处理玻璃纤维增强淀粉/PLA复合材料玻璃化转变温度、重结晶温度、结晶度和热稳定性均依次提高。受玻璃纤维与淀粉/PLA基体界面黏结效果的影响,马来酸酐、KH550、KH570、KH560处理玻璃纤维增强淀粉/PLA体系的储能模量和复数黏度依次增大。 相似文献
186.
Christoph Weigel Valeriya Cherkasova Mathias Holz Hai Binh Phi Christian Görner Tenorio Björn Wilbertz Leonard Voßgrag Thomas Fröhlich Steffen Strehle 《Advanced Engineering Materials》2023,25(9):2201873
Ultralow expansion (ULE) glasses are of special interest for temperature stabilized systems for example in precision metrology. Nowadays, ULE materials are mainly used in macroscopic and less in micromechanical systems. Reasons for this are a lack of technologies for parallel fabricating high-quality released microstructures with a high accuracy. As a result, there is a high demand in transferring these materials into miniaturized application examples, realistic system modeling, and the investigation of microscopic material properties. Herein, a technological base for fabricating released micromechanical structures and systems with a structure height above 100 μm in ULE 7972 glass is established. Herein, the main fabrication parameters that are important for the system design and contribute thus to the introduction of titanium silicate as material for glass-based micromechanical systems are discussed. To study the mechanical properties in combination with respective simulation models, microcantilevers are used as basic mechanical elements to evaluate technological parameters and other impact factors. The implemented models allow to predict the micromechanical system properties with a deviation of only ±5% and can thus effectively support the micromechanical system design in an early stage of development. 相似文献
187.
K. Malik F. Ahmad N. A. Yunus T. Nakato E. Mouri S. Dawood I. R. Memon 《Materialwissenschaft und Werkstofftechnik》2023,54(9):1157-1166
This research aims to develop a method for the amalgamation of graphene nanoplatelets in glass/epoxy composites. The poor interface bonding between the fiber and matrix is critical and hinders the full performance of the composites. Glass fabric and epoxy were used as reinforcement and matrix in the composite, respectively. Graphene nanoplatelets were utilized as an additional nano-materials filler for the composites. Glass/graphene/epoxy and glass/epoxy composites were fabricated via vacuum infusion molding. The new method of applying graphene nanoplatelets as secondary reinforcement in the composite was developed based on proper functionalization in the sonication process. The physical, tensile, flexural, and short beam interlaminar properties of fabricated composites were examined to analyze the method's effectiveness. The results showed that density decreased by around 5 %; however, thickness increased by around 34 % after introducing graphene nanoplatelets into the composites. The tensile strength and modulus of the composites declined by approximately 19 %, on the other hand, flexural strength and modulus increased by around 63.3 % and 8.3 %, respectively, after the addition of graphene nanoplatelets into the composites. Moreover, interlaminar shear strength of the composite was enhanced by approximately 50 %. 相似文献
188.
189.
一种测量透明平行平板折射率的新方法 总被引:1,自引:0,他引:1
通过测量激光细光束经平行平板玻璃所产生的位移,可确定平行平板的的折射率。本文阐述了该方法的测量原理,给出了测量公式,并详细分析了测量误差。计算机模拟计算结果表明,当平板厚度为50mm时,如果入射角测量标准偏差为1”,平板厚度和光线位移量测量标准偏差均为0.001mm,则折射率测量的标准偏差可达6×10~(-5),此时入射角约55°。 相似文献
190.
针对玻璃深加工企业提出的信息化管理需求,通过深入研究分析玻璃深加工流程中需要信息化的各个环节,开发出一个计算机辅助管理系统.系统中本地采用C/S网络体系结构,异地数据通过zlibEx压缩后通过串口实现远程实时安全传输.系统中只需在生成订单时一次输入原始数据,其它功能模块共享原始数据,自动生成各种所需的报表.采用改进的启发式动态寻优方法实现优化切割,改变了手工排料,提高了玻璃原片利用率.该管理系统投入使用后,企业员工的工作效率和经济效益都明显提高,表明了该管理系统的有效性和可行性. 相似文献