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121.
The effect of WO3 on thermal behaviour and thermal stability of ZnO–P2O5–WO3 glasses prepared in compositional series (100 ? x)[0.5ZnO–0.5P2O5] ? xWO3 (x = 0–60) was investigated by heating microscopy and the results were correlated with the results determined by conventional thermodilatometry and differential thermal analysis. Thermoanalytical studies showed that the glass transformation temperature and dilatation softening temperature increase with increasing WO3 content while thermal expansion coefficient decreases. The highest stability towards crystallization possess glasses containing 20–30 mol% WO3. Major compounds formed by the crystallization of the glasses were Zn(PO3)2, WO3 and W18P2O59. The values of sphere temperature, hemisphere temperature and flow temperature obtained using heating microscopy were strongly influenced by the degree of crystallization process at the sintering. 相似文献
122.
Yu Mo Lei Zhao Chia-Lung Chen Giin Yu Amy Tan Jing-Yuan Wang 《Journal of Thermal Analysis and Calorimetry》2013,111(1):781-788
Pyrolysis is one important way to treat polystyrene waste and upcycle it into useful materials. A comparative pyrolysis study of virgin polystyrene (VPS) and two types of commonly used polystyrene products, expanded polystyrene (EPS) and polystyrene container (CPS) was carried out. Various values were found in the thermodynamic study and kinetic study of VPS, EPS, and CPS pyrolysis, suggesting distinct thermal degradation characteristics of these materials. The energy barrier order of the pyrolysis processes was EPS, CPS, VPS, showing activation energy of 230, 219, and 145 kJ mol?1, respectively. The order of amount of heat absorbed was EPS, CPS, VPS, with enthalpy of 224, 213, and 139 kJ mol?1, respectively. The reaction favorability order was EPS, CPS, and VPS with Gibbs free energy of 118, 132, and 210 kJ mol?1, respectively. Thermogravimetric analysis indicated the use of high heating rate would increase the reaction rate and shorten the reaction time. Product evolution profiles showed that VPS and CPS pyrolysis produced mainly aromatics, while EPS pyrolysis produced aromatics at the initial phase of the reaction and aliphatic hydrocarbon at the latter phase. The diverse pyrolysis behaviors of VPS, EPS, and CPS demonstrated that an examination on different polystyrene materials was desired to optimize the pyrolysis conditions and product distribution, and thus benefit the process of valuable materials recovery. 相似文献
123.
Abstract The phase diagram of a two component system composed of two smectic compounds: 4-octyloxy-4′-cyanobiphenyl (8OCB) and 4-isothiocyanatophenyl 4-butylbenzoate (4TPB) was investigated. Three Miesowicz viscosity coefficients η1, η2, η3 and the refractive indices at different temperatures as well as the enthalpies of the phase transitions were measured. It was stated, that the properties of the induced nematic phase, for example, the nematic phase existing between two smectic regions, are the same as the ones observed in the case of low viscosity nematic mesogens. 相似文献
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Yuetian Yan Guodong Chen Hui Wei Richard Y.-C. Huang Jingjie Mo Don L. Rempel Adrienne A. Tymiak Michael L. Gross 《Journal of the American Society for Mass Spectrometry》2014,25(12):2084-2092
Epitope mapping is an important tool for the development of monoclonal antibodies, mAbs, as therapeutic drugs. Recently, a class of therapeutic mAb alternatives, adnectins, has been developed as targeted biologics. They are derived from the 10th type III domain of human fibronectin (10Fn3). A common approach to map the epitope binding of these therapeutic proteins to their binding partners is X-ray crystallography. Although the crystal structure is known for Adnectin 1 binding to human epidermal growth factor receptor (EGFR), we seek to determine complementary binding in solution and to test the efficacy of footprinting for this purpose. As a relatively new tool in structural biology and complementary to X-ray crystallography, protein footprinting coupled with mass spectrometry is promising for protein–protein interaction studies. We report here the use of fast photochemical oxidation of proteins (FPOP) coupled with MS to map the epitope of EGFR-Adnectin 1 at both the peptide and amino-acid residue levels. The data correlate well with the previously determined epitopes from the crystal structure and are consistent with HDX MS data, which are presented in an accompanying paper. The FPOP-determined binding interface involves various amino-acid and peptide regions near the N terminus of EGFR. The outcome adds credibility to oxidative labeling by FPOP for epitope mapping and motivates more applications in the therapeutic protein area as a stand-alone method or in conjunction with X-ray crystallography, NMR, site-directed mutagenesis, and other orthogonal methods. Figure
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基于第一性原理计算方法,对含空位缺陷的V2C(MXene)在不同位点修饰单原子Al的相关性能进行系统研究.研究表明,几何优化后得到含空位缺陷的V2C稳定结构表面能为-3075.53 J/m2,单原子Al修饰本征V2C单原子的吸附能为1.5511eV、单原子Al修饰空位缺陷V2C的吸附能为-2.0763 eV,这表明含空位缺陷的V2C,由于单原子Al的修饰可以明显改善晶体结构稳定性.进一步从态密度、分波态密度、吸氢能力研究发现,各体系态密度和分波态密度均出现分波越过费米能级的现象,表现出较强的金属性;V2C吸附H2气体分子吸附能为-7.5867 eV,而空位缺陷V2C和单原子Al修饰空位缺陷V2C两个体系对H2气体分子的吸附能仅为-0.9851 eV、-2.7130 eV,均未能进一步改善V2C对H2气体分... 相似文献
130.
Evolution speed of an open quantum system is vividly influenced by the structure of environments. The strong system‐environment coupling is found to be able to accelerate quantum evolution. In this work, we propose a different method of governing the quantum speedup via engineering multiple environments. It is shown that, with a judicious choice of the number of coupling environments, the quantum speedup of an open system can be achieved even under weak system‐environment coupling conditions. The mechanism for the speedup is due to the switch between Markovian and non‐Markovian regions by manipulating the number of the surrounding environments. In addition, we verify the above phenomena by using quantum dots embedded in a planar photonic crystal under current technologies. These results provide a new degree of freedoms to accelerate quantum evolution of open systems. The strong system‐environment coupling can speed up the quantum evolution process. This work shows that, via engineering multiple environments, one can speed up the evolution process even under weak coupling conditions. 相似文献