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关键词： YSZ   Sintering   Reducing atmosphere   CO2+air atmosphereXPS   Electrical conductivity  

摘要： Given the need to process anodes and composites based on nano-YSZ in reducing or in air containing additional CO2 atmospheres for the fabrication of solid oxide fuel cells (SOFCs), and solid oxide electrolysis cells (SOECs), we have studied the effect of the exposure to CO+N-2/H-2 or CO2+air mixtures during sintering of YSZ green pellets, prepared from commercial nanopowders, on their structure, microstructure, chemical composition and their electrical properties. The reduced sample shows Raman bands at 1298 and 1605 cm(-1) that are assigned to the D and G bands of carbon, respectively. The bands intensity ratio ID/IG indicates a larger content of disordered carbon. X-ray photoelectron spectroscopy (XPS) shows that C is present in the reduced samples as reduced carbon. However, the samples sintered in CO2+air present C as carbonate-type. Impedance spectroscopy reveals that the highest total conductivity is for the reduced samples in the whole range of studied temperatures. In addition, sintering in CO2+air causes a detrimental effect on the grain boundary conductivity and therefore, on the total electrical conductivity of YSZ. It can be due to the presence of impurities such as carbonates and oxidised or even, polymerised carbonaceous species located at those areas. (C)2022 The Author(s). Published by Elsevier B.V. CC_BY_4.0

关键词： UV irradiation   Superhydrophobicity   Acetylated wood   Surface modification   Lignin degradation   Wettability  

摘要： The effect of prolonged ultraviolet (UV) irradiation on the performance of superhydrophobized birch and acetylated birch wood was investigated. The surface modification of the wood was based on a newly developed method using silicone nanofilaments. The combination of surface modification and acetylation of wood showed good wetting resistance also after 600 h of UV exposure, with water contact angles greater than 140 degrees and water uptake 30 times lower by weight than that of the non-surface-modified wood as determined by multicycle Wilhelmy plate measurements. Scanning electron microscopy images revealed that the silicone nanofilaments can still be observed on the wood samples after UV irradiation. The surface-modified wood samples exhibited significant color change after UV exposure. FTIR spectra showed that lignin was degraded on both the nonsurface-modified wood surfaces and the wood surface-modified with the silicone nanofilaments.

关键词： fatty acid amide hydrolase   monoacylglycerol lipase   inhibitors   carbamate   Caco-2 cell permeation  

摘要： A series of hexafluoroisopropyl carbamates with indolylalkyl- and azaindolylalkyl-substituents at the carbamate nitrogen was synthesized and evaluated for inhibition of the endocannabinoid degrading enzymes fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL). The synthesized derivatives with butyl to heptyl spacers between the heteroaryl and the carbamate moiety were inhibitors of both enzymes. For investigated compounds in which the alkyl chain was partially incorporated into a piperidine ring, different results were obtained. Compounds with a methylene spacer between the piperidine ring and the heteroaromatic system were found to be selective MAGL inhibitors, while an extension of the alkyl spacer to two to four atoms resulted in dual inhibition of FAAH/MAGL. The only small change in enzyme inhibitory activity with variation of the heteroaromatic system indicates that the reactive hexafluoroisopropyl carbamate group is mainly responsible for the strength of the inhibitory effect of the compounds. Selected derivatives were also tested for hydrolytic stability in aqueous solution, liver homogenate and blood plasma as well as for aqueous solubility and for permeability in a Caco-2 cell model. Some compounds showed a slightly higher MAGL inhibitory effect than the known selective MAGL inhibitor ABX-1431 and also partly surpassed this substance with regard to certain physicochemical and biochemical properties such as water solubility and cell permeability.

关键词： cancer   drug design   epigenetics   histone deacetylases   inhibitors  

摘要： Herein we report the structure-activity and structure-physicochemical property relationships of a series of class I selective ortho-aminoanilides targeting the "foot-pocket" in HDAC1&2. To balance the structural benefits and the physicochemical disadvantages of these substances, we started with a set of HDACi related to tacedinaline (CI-994) and evaluated their solubility, lipophilicity (log D-7.4) and inhibition of selected HDAC isoforms. Subsequently, we selected the most promising "capless" HDACi and transferred its ZBG to our previously published scaffold featuring a peptoid-based cap group. The resulting hit compound 10 c (LSH-A54) showed favorable physicochemical properties and is a potent, selective HDAC1/2 inhibitor. The following evaluation of its slow binding properties revealed that LSH-A54 binds tightly to HDAC1 in an induced-fit mechanism. The potent HDAC1/2 inhibitory properties were reflected by attenuated cell migration in a modified wound healing assay and reduced cell viability in a clonogenic survival assay in selected breast cancer cell lines.

关键词： 物理化学   OBE理念   应用型高校   复合材料   工程认证  

摘要： 分析了物理化学课程特点以及目前物理化学教学过程中存在的问题。根据OBE教学理念的要求,基于应用型本科高校的定位和复合材料专业的特点,并结合工程教育专业认证要求,从课程大纲、课程目标教学方法和考核方式等方面探讨了应用型高校复合材料专业物理化学课程的改革。通过实例阐述了OBE理念在物理化学课程中的应用过程,并分析了改革前后的效果。

关键词： 辐照技术   塑料包装材料   辐解行为   迁移行为   食品安全  

摘要： 目的辐照是食品行业中主要的消毒灭菌技术之一,通过系统综述国内外学者关于塑料食品包装材料辐照前后的变化,探究辐照技术对其物理化学性能的影响。方法介绍食品辐照技术及其发展过程,重点分析辐照对常见塑料食品包装材料的辐解行为、迁移行为及物理性能的影响。结果许多学者的研究都证明辐照会对塑料包装材料的光学、热学、力学性能及阻隔性等产生一定的影响,并导致降解产物的出现。结论辐照对塑料食品包装材料的性能存在一定影响,需考虑材料辐照后在食品安全和物理性能方面的变化,且相关的法律法规尚有完善空间。

关键词： 物理化学   过程性考核   考核指标   教学实践  

摘要： 针对“物理化学B”课程教学过程考核中存在问题,采用“智慧教学”“翻转课堂”和“线上线下混合教学模式”的新手段对课程的过程考核方式和指标进行了重新设计,采取多元考核模式,科学设计考核量化指标使其具有可操作性,使考核和评价贯穿于各个教学环节。教学实践结果显示,过程考核模式可有效解决传统考核模式标准模糊和区分度不大的问题,为物理化学课程教学效果的改善和学生学习兴趣的培养提供了参考和借鉴。

关键词： specific conductance   artifact correction   electrochemical impedance spectroscopy   Markov chain Monte Carlo   high-temperature brine  

摘要： Specific conductance and frequency-dependent resistance (impedance) data are widely utilized for understanding the physicochemical characteristics of aqueous and non-aqueous fluids and for evaluating the performance of chemical processes. However, the implementation of such an in-situ probe in high-temperature and high-pressure environments is not trivial. This work provides a description of both the hardware and software associated with implementing a parallel-type in-situ electrochemical sensor. The sensor can be used for in-line monitoring of thermal desalination processes and for impedance measurements in fluids at high temperature and pressure. A comparison between the experimental measurements on the specific conductance in aqueous sodium chloride solutions and the conductance model demonstrate that the methodology yields reasonable agreement with both the model and literature data. A combination of hardware components, a software-based correction for experimental artifacts, and computational fluid dynamics (CFD) calculations used in this work provide a sound basis for implementing such in-situ electrochemical sensors to measure frequency-dependent resistance spectra.

关键词： 课程思政   思政元素   挖掘   探究  

摘要： 我国高等教育的目的是培养德智体美劳全面发展的、对社会发展有用的人才。课程思政是培养我国高级人才的一个重要手段。课程思政要求教师将专业教育与思政教育有机融为一体,实现立德树人的目的。根据教育部发布的《高等学校课程思政建设指导纲要》,文章以《物理化学实验》为例,深入挖掘该课程的思政元素,分析了预期教学效果,进一步实现了课程思政教育。

关键词： 立德树人   物理化学课程   教学改革  

摘要： 随着立德树人教育理念的提出,对于物理化学这门课程的教学要求也有了新的变化,不仅要重视对学生学科知识的培养,同时需要重视将立德树人的相关内容与学科知识进行紧密相连,在物理化学课程中能够渗透与其相关的知识,帮助学生成为全面发展,有着良好道德情操的人。因为这门课程的重要的基础专业课程,其主要讲授的内容的化学的分支,并且因为是重要的专业课程,所以对于学生的素质和独立分析问题、解决问题的能力有着重要的培养作用。因此在立德树人背景下实现对物理化学课程的有效教育改革,还需要能够深入了解学科知识的特点,以及立德树人的具体要求,进而能够找到两者之间的契合点,能够实现物理化学课程的有效改革,实现对学生的良好培养。