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101.
《Solar Energy》2013
A viscous TiO2 paste was prepared by ball-milling commercially available P25 with ethylene glycol and citric acid. The conventional three- or four-fold deposition process was replaced by a single coating-sintering step of TiO2 compound. That is coating the paste on Fluorine-doped SnO2 conductive glass, followed by sintering at high temperature. TiO2 films varying from 8 μm to 24 μm could be fabricated by this single coating-sintering step. The high viscosity of the paste, the esterification between ethylene glycol and citric acid and the subsequently polyester decomposition in the sintering process were the reasons to make high-quality thick film without cracking and delamination. 7.36% photoelectrical-conversion efficiency was achieved by using the photoelectrode with its P25 film thickness of 14.3 μm. Therefore, the paste would have promising applications for industrial production because of its low-price and simple process. 相似文献
102.
《Food Control》2016
The use of secondary metabolites of lactic acid bacteria for preservation of foods is increasingly gaining interest to the food industry to replace synthetic preservatives. In this study, the cell free supernatant containing peptides obtained from Lactobacillus plantarum IS10 was fractionated by size exclusion chromatography using sephadex G-25, and tested against Aspergillus flavus MD3, Penicillium roqueforti MD4 and Eurotium rubrum MD5. Among the fractions, fraction number 10 showed 60% antifungal activity at a concentration of 0.02 mg peptide/mL. Four novel peptides out of twenty peptides obtained from fraction 10 were identified and determined by de novo sequencing. Peptide FPSHTGMSVPPP with a net charge +1, hydrophobicity ratio 58% and molecular weight of 1253 was further studied. The selected peptide showed a good activity at a concentration of 5 mg/mL against selected fungi and poor activity at low concentrations. This work indicates that L. plantarum IS10 has the capability of producing peptides which are affective against spoilage fungi. 相似文献
103.
本文将反胶束法制备的CdS晶体键合在经γ 巯丙基三甲氧基硅(MPTMS)修饰的P25粒子的表面.产物P25 MPTMS CdS复合粒子的紫外 可见吸收和粒子形貌分别用漫反射光谱仪和透射电镜进行了表征.同时也进行了光催化降解甲基橙溶液的实验,发现P25 MPTMS CdS在紫外和可见光下区域都具备较高的光催化活性.经过18h的可见光照后(λ>400nm),紫外 可见光谱表明,P25 MPTMS CdS粒子具备较好的光稳定性. 相似文献
104.
Rahul Bhandari;Prosanta Biswas;Manab Mallik;Manas Kumar Mondal; 《Advanced Engineering Materials》2024,26(2):2300845
This study investigates the wear characteristics of Al–25Mg2Si composite synthesized via gravity casting. The research aims to understand the influence of applied load, test temperature, contact condition (dry and lubrication), and sliding distance on wear characteristics. Results show that higher loads and temperatures lead to increased wear loss and coefficient of friction. The worn surface morphology for higher loads and temperature shows deeper scratches and grooves, indicating severity in wear. The debris size and volume increase with an increase in load and temperature. The dominant mechanism is abrasive, adhesive, and oxidative for both the room- and high-temperature dry sliding conditions. However adhesive and oxidative wear increase with the increase in test temperature. Abrasive wear is the only wear mechanism present during the lubricating sliding condition. Wear transition is noticed during the wear map analysis subjected to load, temperature, and sliding distance. In the case of room-temperature test, severe–moderate–mild wear transition occurs with the increase in sliding distance and mild–moderate–severe wear transition occurs with the increase in test temperature and applied load. The roughness of the worn surface increases with an increase in applied load and temperature and the use of lubricant hugely reduces the surface roughness. 相似文献
105.
106.
In this paper, an experimental wind tunnel test campaign to assess the possibility of using cup anemometers at high altitude (~20 km) is performed. The experimental procedure consists of measuring the evolution of the rotational frequency for different wind dynamic pressures for different cups and the center of rotation radius. With particular interest on the point at which the rotation stops for decreasing values of the dynamic pressure is considered as the limit value for the anemometer operation. The results show that large cup radius anemometer rotors present more stable behavior (its stopping point at low wind speeds being less affected by the cups’ center rotation radius). The authors conclude that cup anemometers can be used at high altitude above ground. Results show that an anemometer equipped with a 40 mm cup radius rotor could be considered operative up to an altitude of 25 km above ground. 相似文献
107.
108.
Maia M. Svanadze 《热应力杂志》2018,41(8):1022-1041
In this article, the linear theory of binary thermoviscoelastic mixtures is considered and the basic boundary value problems (BVPs) of steady vibrations are investigated. Namely, the fundamental solution of the system of equations of steady vibrations is constructed explicitly and its basic properties are established. Green’s second and third identities are obtained and the uniqueness theorems for classical solutions of the internal and external basic BVPs of steady vibrations are proved. The surface and volume potentials are constructed and their basic properties are given. The determinants of symbolic matrices are calculated explicitly. The BVPs are reduced to the always solvable singular integral equations for which Fredholm’s theorems are valid. Finally, the existence theorems for classical solutions of the internal and external BVPs of steady vibrations are proved by the potential method and the theory of singular integral equations. 相似文献
109.
Mark W. Maier 《Systems Engineering》2019,22(4):335-347
A “portfolio‐of‐systems” is a collection of systems related by common management and budgeting, and at least some relationship to mission or missions. A portfolio‐of‐systems describes the not uncommon situation where an office is responsible for multiple systems in multiple phases of development but those systems are not related by common design, common manufacturing, or necessarily interconnected operationally. The relationship is fundamentally one of management, although other linkages might be present or designed if such additional linkages are deemed beneficial. The portfolio‐of‐systems concept differs from systems‐of‐systems and product‐line or family‐of‐systems constructs. This paper describes generalizations of architecting techniques for portfolio situations, particularly recognizing the presence of many largely independent components in multiple stages of development with an ongoing or episodic process. The paper presents two case studies of actual portfolios: One a portfolio of operational demonstration systems and the other a portfolio of weather satellites. 相似文献
110.
Meizhu Wang Yu Cao Maoning Xia Abdullah M.S. Al-Hatmi Weizheng Ou Yanyan Wang Andriy A. Sibirny Liang Zhao Chenggang Zou Wanqing Liao Fengyan Bai Xie Zhi Sybren de Hoog Yingqian Kang 《Yeast (Chichester, England)》2019,36(5):363-373
A set of 185 strains of Candida albicans from patients with vulvovaginal candidiasis (VVC) and from non-VVC clinical sources in southwest China was analysed. Strains were subjected to genotyping using CAI microsatellite typing and amplification of an intron-containing region of the 25S rRNA gene. Microsatellite genotypes of strains from non-VVC sources showed high polymorphism, whereas those of VVC were dominated by few, closely similar genotypes. However, among non-VVC strains, two genotypes were particularly prevalent in patients with lung cancer. 25S rDNA genotype A was dominant in VVC sources (86.7%), whereas genotypes A, B, and C were rather evenly distributed among non-VVC sources; known genotypes D and E were not found. In an experimental mouse model, isolates from lung cancer and AIDS patients proved to have higher virulence than VVC strains. Among 156 mice infected with C. albicans, 19 developed non-invasive urothelial carcinoma. No correlation could be established between parameters of virulence, source of infection, and incidence of carcinoma. C. albicans strains from VVC were less susceptible to itraconazole than the strains from non-VVC sources, whereas there was small difference in antifungal susceptibility between different 25S rDNA genotypes of C. albicans tested against amphotericin B, itraconazole, fluconazole, and flucytosine. 相似文献