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91.
Thermophysical properties of molten semiconductors are reviewed. Published data for viscosity, thermal conductivity, surface tension, and other properties are presented. Several measurement methods often used for molten semiconductors are described. Recommended values of thermophysical properties are tabulated for Si, Ge, GaAs, InP, InSb, GaSb, and other compounds. This review shows that further measurements of thermophysical properties of GaAs and InP in the molten state are required. It is also indicated that a very limited amount of data on emissivity is available. Space experiments relating to thermophysical property measurements are described briefly.Nomenclature
Density
-
C
p
Specific heat
-
Kinematic viscosity
-
Dynamic viscosity=
-
Thermal diffusivity
-
Thermal conductivity=Cp
-
Volumetric thermal expansion coefficient
-
Surface tension
-
d/dT
Temperature coefficient of surface tension
-
g
Gravitational acceleration
-
T
Temperature
-
T
Temperature difference
-
L
Characteristic dimension 相似文献
92.
航空火警控制盒测试设备是一套主要用于火警控制盒、火警探测器、主告警控制盒、告警控制盒等的校验、故障诊断的设备。介绍了一种基于LabVIEW的航空火警控制盒测试设备的方法,利用PC机中的LabVIEW图形化编程软件采用随机数读取并且显示,再对信号进行分析,对超限信号起到报警功能。 相似文献
93.
Ravan A. Rahimov Gulnara A. Ahmadova Seyid-Zeynab F. Hashimzade Elmar Imanov Hajibala G. Khasiyev Nazani K. Karimova Fedor I. Zubkov 《Journal of surfactants and detergents》2021,24(3):433-444
Two new classes of gemini cationic surfactants—hexanediyl-1,6-bis[(isopropylol) alkylammonium] dibromide {in the abbreviation form: CnC6Cn[iPr-OH] and CnC6Cn[iPr-OH]2; alkyl: CnH2n + 1 with n = 9, 10, 12 and 14}—have been synthesized by interaction of alkyl bromides with N,N′-di-(isopropylol)-1,6-diaminohexane and N,N,N′,N′-tetra-(isopropylol)-1,6-diaminohexane. The surface tension, electrical conductivity, and dynamic light scattering (DLS) techniques were used to investigate the aggregation properties of the gemini cationic surfactants in aqueous solution. The formation of critical aggregates at two concentrations in an aqueous solution from obtained gemini cationic surfactants were determined via the tensiometric method. Thus, these gemini cationic surfactants start to form aggregates at concentrations well below their critical micelle concentrations (CMC). The surface properties and the binding degree (β) of the opposite ion were tested against the length of the surfactant hydrocarbon chain and the number of the isopropylol groups in the head group. By applying the DLS technique, it was explored that how the number of isopropylol groups in gemini cationic surfactants with C12H25 chain affects the sizes of micelles at concentrations greater than CMC. It was discovered that the obtained gemini cationic surfactants have a biocidal character. 相似文献
94.
Yuning Lou Yajuan Dong Xiaoyong Wang Feirong Gong Min Zhao Zongming Rong 《Journal of surfactants and detergents》2021,24(1):3-13
Two generations of novel linear-dendritic carboxylate surfactants C18-G1-(COONa)2 and C18-G2-(COONa)4 have been synthesized by the divergent method and their structures are characterized by 1H Nuclear Magnetic Resonance and Infrared analysis. The electrical conductivity measurement is used to measure the Krafft temperatures of C18-G1-(COONa)2 and C18-G2-(COONa)4, which are much smaller than those of the corresponding conventional surfactant sodium stearate. The markedly enhanced solubility of two linear-dendritic surfactants is ascribed to the high hydrophilicity of surfactant headgroups induced by the carboxylate and ester groups. The critical micelle concentration (CMC) values obtained from both the electrical conductivity and surface tension measurements indicate that the micellizations of linear-dendritic surfactants become favorable with the increase in the number of the surfactant headgroup. However, the surface activity parameters including the surface tension at the CMC, maximum surface excess, and minimum surface area reveal that C18-G1-(COONa)2 exhibits greater efficiency in absorbing at the air/water interface compared to C18-G2-(COONa)4, owing to their different steric repulsions of the surfactant headgroups. In addition, C18-G1-(COONa)2 and C18-G2-(COONa)4 have higher emulsifying ability than the conventional surfactants sodium stearate and sodium octadecyl sulfate. 相似文献
95.
Su-Min Baek Seoung-Woo Lee Tae-Un Kim Seong-Kyoon Choi Sungho Yun Won-Jae Lee Se-Hyeon Han Il-Hwa Hong Sang-Joon Park Tae-Hwan Kim Kyu-Shik Jeong Jin-Kyu Park 《International journal of molecular sciences》2021,22(5)
Senescence marker protein 30 (SMP30) is a cell survival factor playing an important role in vitamin C synthesis and antiapoptosis. Moreover, its cytoprotective role suggests a possibility to be related to cancer cell survival. Mammary carcinoma is a common cancer in both humans and animals. Because of its histopathological diversity, especially in the early stage, histopathological diagnosis may be complicated; therefore, a diagnostic marker is helpful for confirmation. The present study analyzed the expression pattern of SMP30 in mammary carcinoma in humans, dogs, and cats. Immunohistochemistry, immunofluorescence, and western blot analysis were used to investigate SMP30 expression patterns. The expression was specifically observed in neoplastic glandular epithelial cells. The expression increased with the malignancy of glandular epithelial cells with a highly proliferative status. However, SMP30 expression was low in normal mammary gland tissues or well-differentiated adenoma tissues. The patterns were consistently reproduced in canine primary mammary carcinoma cells and MCF-7 and MDA-MB-231 human carcinoma cell lines. This study provides useful information to understand SMP30 expression in various stages of mammary carcinoma and to suggest its utility as a pan-species diagnostic marker, thereby helping to establish strategies for diagnosing mammary carcinoma in several species. 相似文献
96.
有机涂层钢板生产线主要工艺 总被引:1,自引:0,他引:1
介绍了有机涂层钢板生产线上钢基板的预处理,全线张力控制,纠偏装置的布置,固化炉的选型. 相似文献
97.
针对IBM STBX25XX机顶盒的硬件结构特点,设计了Hopen机顶盒软件平台.通过对Hopen嵌入式实时操作系统内核的移植、各功能部件驱动的定制和开发,使得Hopen机顶盒软件平台可以运行在PowerPC架构的硬件上,完成了数字电视节目的播放功能,从而拓宽了Hopen的应用领域. 相似文献
98.
Dr. Zhichao Du Dr. Guolong Li Dr. Haixia Ge Xiaoyang Zhou Prof. Jian Zhang 《ChemMedChem》2021,16(9):1488-1498
To systematically evaluate the impact of neoglycosylation upon the anticancer activities and selectivity of steroids, four series of neoglycosides of diosgenin, pregnenolone, dehydroepiandrosterone and estrone were designed and synthesized according to the neoglycosylation approach. The structures of all the products were elucidated by NMR analysis, and the stereochemistry of C20-MeON-pregnenolone was confirmed by crystal X-ray diffraction. The compounds′ cytotoxicity on five human cancer cell lines was evaluated using a Cell Counting Kit-8 assay, and structure–activity relationships (SAR) are discussed. 2-deoxy-d -glucoside 5 k displayed the most potent antiproliferative activities against HepG2 cells with an IC50 value of 1.5 μM. Further pharmacological experiments on compound 5 k on HepG2 cells revealed that it could cause morphological changes and cell-cycle arrest at the G0/G1 phase and then induced the apoptosis, which might be associated with the enhanced expression of high-mobility group Box 1 (HMGB1). Taken together, these findings prove that the neoglycosylation of steroids could be a promising strategy for the discovery of potential antiproliferative agents. 相似文献
99.
Muhammad Khurram Tufail Niaz Ahmad Le Yang Lei Zhou Muhammad Adnan Naseer Renjie Chen Wen Yang 《中国化学工程学报》2021,39(11):16-36
The development of an inorganic electrochemical stable solid-state electrolyte is essentially responsible for future state-of-the-art all-solid-state lithium batteries (ASSLBs). Because of their advantages in safety, working temperature, high energy density, and packaging, ASSLBs can develop an ideal energy storage system for modern electric vehicles (EVs). A solid electrolyte (SE) model must have an economical synthesis approach, exhibit electrochemical and chemical stability, high ionic conductivity, and low interfacial resistance. Owing to its highest conductivity of 17 mS·cm-1, and deformability, the sulfide-based Li7P3S11 solid electrolyte is a promising contender for the high-performance bulk type of ASSLBs. Herein, we present a current glimpse of the progress of synthetic procedures, structural aspects, and ionic conductivity improvement strategies. Structural elucidation and mechanistic approaches have been extensively discussed by using various characterization techniques. The chemical stability of Li7P3S11 could be enhanced via oxide doping, and hard and soft acid/base (HSAB) concepts are also discussed. The issues to be undertaken for designing the ideal solid electrolytes, interfacial challenges, and high energy density have been discoursed. This review aims to provide a bird's eye view of the recent development of Li7P3S11-based solid-state electrolyte applications and explore the strategies for designing new solid electrolytes with a target-oriented approach to enhance the efficiency of high energy density all-solid-state lithium batteries. 相似文献
100.
界面性能对复合驱提高采收率有重大的影响,界面张力越低,洗油效率越高;Zeta电位越高,油水乳状液越稳定。研究了各类无机盐对新疆油田复合驱界面性能的影响。结果显示,Zeta电位的绝对值随着无机盐浓度的增高而增大;无机碱中,碳酸根离子降低界面张力效果最好,氢氧根次之,碳酸氢根最差;阳离子中,钾离子降低界面张力效果最好,其次是钠离子,镁离子会略微提高界面张力,钙离子则会大幅度提高界面张力;阴离子中,与硫酸根相比,氯离子能更好地降低界面张力。通过以上研究,确定了Q站污水处理站外排水更适合三元复合驱配液。 相似文献