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81.
In this work, the effects of shear rate on viscosity of selected pure food grade oils (castor and canola) are investigated. The rheological behavior of castor–canola oil mixture is also studied through modeling the experimental data. The effect of shear rate on the variation of viscosity was clearly observed. Interpretations of the results from rheological models indicate that these food grade oils belong to pseudo‐plastic category. The results also show that among the six used mixing rules, Grunberg–Nissan model seems very well fitted to the experimental data.  相似文献   
82.
The main objective of this study was to compare the spouted bed and microwave assisted spouted bed drying on affecting physical properties of parboiled wheat and bulgur. Drying was performed at different temperatures (50 °C, 70 °C, 90 °C) and microwave powers (288 W, 624 W). Bulk and apparent density, bulk and apparent porosity, sphericity, color, microstructure and pore size distribution of parboiled wheat were investigated after drying. Yield and water absorption capacity were determined in bulgur samples. The effect of air temperature on physical properties of product except color was not significant in spouted bed drying. More porous structure was observed in wheat samples dried in microwave assisted spouted bed compared to air dried ones. Sphericity and bulk density were higher when high temperature was combined with high microwave power. In microwave assisted spouted bed drying, similar yield value but lower water absorption capacity of bulgur were observed as compared to spouted bed drying.  相似文献   
83.
We report herein the synthesis and full characterizations of the first examples of gallium complexes based on “privileged” aminobisphenolate ligands which are easily available. These complexes turned out to be extremely active in the ring-opening polymerization of ε-caprolactone even at room temperature and highly active in the ROP of L-lactide. The combination of factors such as the easy availability of these compounds and the supposedly low toxicity, together with the extremely high activity in ROP, allows us to consider these compounds as suitable for use on an industrial scale for the synthesis of biodegradable polymers for biomedical applications.  相似文献   
84.
Chemotherapy of soft tissue sarcomas (STS) is restricted by low chemosensitivity and multiple drug resistance (MDR). The purpose of our study was the analysis of MDR mechanism in different types of STS. We assessed the expression of ABC-transporters, MVP, YB-1, and analyzed their correlation with chemosensitivity of cancer cells. STS specimens were obtained from 70 patients without metastatic disease (2018–2020). Expression level of MDR-associated genes was estimated by qRT-PCR and cytofluorimetry. Mutations in ABC-transporter genes were captured by exome sequencing. Chemosensitivity (SI) of STS to doxorubicin (Dox), ifosfamide (Ifo), gemcitabine (Gem), and docetaxel (Doc) was analyzed in vitro. We found strong correlation in ABCB1, ABCC1, and ABCG2 expression. We demonstrated strong negative correlations in ABCB1 and ABCG2 expression with SI (Doc) and SI (Doc + Gem), and positive correlation of MVP expression with SI (Doc) and SI (Doc + Gem) in undifferentiated pleomorphic sarcoma. Pgp expression was shown in 5 out of 44 STS samples with prevalence of synovial sarcoma relapses and it is strongly correlated with SI (Gem). Mutations in MDR-associated genes were rarely found. Overall, STS demonstrated high heterogeneity in chemosensitivity that makes reasonable in vitro chemosensitivity testing to improve personalized STS therapy, and classic ABC-transporters are not obviously involved in MDR appearance.  相似文献   
85.
Magnetic resonance imaging-derived entorhinal and hippocampal volumes were measured in 14 nondemented, community-dwelling older adults. Participants were selected so that memory scores from 2 years prior to scanning varied widely but were not deficient relative to age-appropriate norms. A median split of these memory scores defined high-memory and low-memory groups. Verbal memory scores at the time of imaging were lower, and entorhinal and hippocampal volumes were smaller, in the low-memory group than in the high-memory group. Left entorhinal cortex volume showed the strongest correlation (r=.79) with immediate recall of word lists. Left hippocampal volume showed the strongest correlation (r=.57) with delayed paragraph recall. These results suggest that entorhinal and hippocampal volumes are related to individual differences in dissociable kinds of memory performance among healthy older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
86.
牛仔服装的流行始于美国加利福尼亚州,美国人Levi Strauss缝制了第一条牛仔裤,他本人是一位旧金山的巴伐利亚布匹商人.牛仔布一词源于意大利的热那亚,当时的热那亚还是一个独立的共和国,海军势力强大,由于海员的裤子需适用于各种环境,而牛仔裤刚好满足这一要求因此成为热那亚海军的供给.洗涤时,海员们将牛仔裤装在大网袋里拖在舰艇后面冲洗,海水将牛仔裤漂白成泛着白头的蓝色,而手感也变得更加柔软舒适.  相似文献   
87.
The major challenge of the operation of every solar cell based on dye including water splitting solar cell (WSSC) and dye sensitized solar cell (DSSC) is the using organic solvent medium which causes to decompose the solar cell structure, resulting environmental impact. Here, we synthesized and characterized two new ruthenium complexes with nitrogen and oxygen donor ligands for DSSC application which show good stability on TiO2 surface in water solvent. Interestingly, the DSSC based on [Ru(dcbpy)2(DPC)]Cl, where dcbpy = 4,4-dicarboxilic acid 2,2-bipyridin and DPC = diphenylcarbazide, was shown better efficiency in water than methanol dye loading as well as N3 as a benchmark sensitizer in the same condition. The DPC-based exhibited open circuit voltage (Voc) of 0.63 V, short-circuit current density (Jsc) of 2.5 mA/cm2 and fill factor (FF) of 70%, resulting an overall power efficiency of 1.12%. The incident-photon-to-current conversion efficiency (IPCE) value is also reached to 45% for [Ru(dcbpy)2(DPC)]Cl in the same condition It is proposed that the ruthenium complex containing nitrogen and oxygen donor ligands is more stability on TiO2 and prevent the decomposition of TiO2 porous under water solvent condition.  相似文献   
88.
A parametric study of the effect of reference state on the energy and exergy efficiencies of geothermal district heating systems is presented. In this regard, the work consists of two parts: a modeling study covering energy and exergy analysis and a case study covering the actual system data taken from the Salihli Geothermal District Heating System (SGDHS) in Manisa, Turkey. General energy and exergy analysis of the geothermal district heating systems is introduced along with some thermodynamic performance evaluation parameters. This analysis is then applied to the SGDHS using actual thermodynamic data for its performance evaluation in terms of energy and exergy efficiencies. In addition, a parametric study on the effect of varying dead state properties on the energy and exergy efficiencies of the system that has been conducted to find optimum performance and operating conditions is explained. Two parametric expressions of energy and exergy efficiencies were developed as a function of the reference temperature. Both energy and exergy flow diagrams illustrate and compare results under different conditions. It has been observed that the exergy destructions in the system particularly take place as the exergy of the fluid lost in the heat exchanger, the natural direct discharge of the system (pipeline losses), and the pumps, which account for 31.17%, 8.98%, and 4.27% of the total exergy input to the SGDHS, respectively. For the actual system that is presented, the system energy and exergy efficiencies vary between 0.53 and 0.73 and 0.58 and 0.59, respectively.  相似文献   
89.

Geothermal energy is already in the form of heat, and from the thermodynamic point of view, work is more useful than heat because not all heat can be converted to work. Therefore, geothermal resources should be classified according to their exergy, which is a measure of their ability to do work. In recent years there has been a remarkable growth of interest in environmental issues—sustainability and improved management of development in harmony with the environment. Environmental impact assessment is one of the most widely used tools in environmental management. In this study, the environmental and exergetic aspects of geothermal energy, namely the rapid impact assessment matrix method, and, specific exergy index, were studied first. They were then applied to the Tuzla geothermal field in Canakkale and Balcova geothermal field in Izmir, Turkey, respectively. Finally, the results obtained are given and discussed.  相似文献   
90.
The purpose of this survey is about to analyze the heating coefficient of performance (COP) of geothermal district heating systems. Actual system data are taken from the Salihli GDHS, Turkey. The collected data are quantified and illustrated in tables, particularly for a reference temperature for comparison purposes. In this study, firstly energy and COP analysis of the GDHSs is introduced and then Salihli GDHS coefficient of performance results is given as a case study. Moreover, this paper offers an interesting empirical study of certain geothermal systems.  相似文献   
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