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11.
Bin Wang Xin Zhang Hongliang Huang Zhangjing Zhang Taner Yildirim Wei Zhou Shengchang Xiang Banglin Chen 《Nano Research》2021,14(2):507-511
We report a microporous aluminum-based metal-organic framework(MOF),BUT-22 for high methane(CH4),hydrogen(H2),and carbon dioxide(CO2)storage.At 296 K and 80 bar,BUT-22 exhibits a high gravimetric CH4 storage capacity of 530 cm3(STP)/g(0.379 g/g).BUT-22 also has a high gravimetric H2storage capacity of 12 wt.%at 100 bar and 77 K.In addition,the CO2adsorption studies revealed that BUT-22 exhibits a high absolute gravimetric CO2 uptake of 1.7 g/g at 296 K and 40 bar. 相似文献
12.
There is a paucity of data in respect of the nutritional quality of complementary foods for infants and young children aged between 6 and 12 months. In this study, we developed and validated an analytical method for determination of the endocrine-disrupting organochlorine pesticides (OCPs) and elements (As, Cd, and Pb) in infant formula and baby foods. Therefore, it found out the contamination level of the both OCPs and some trace metals (As, Cd, and Pb) in widely consumed infant formula and baby food in Turkey. Metal concentrations in baby foods and infant formula were determined by inductively coupled plasma mass spectrometry. Samples were digested with nitric acid and hydrogen peroxide in a microwave oven. Determination of 24 organochlorine pesticide residues in baby foods and infant formula was completed by using gas chromatography double mass spectrometry. QuEChERS extraction method was carried out in the sample preparation part. The analytical performance of the entire procedure, such as linearity, the detection of limit, limit of quantification, specificity/selectivity, recovery (%), and precision, were assessed. The recoveries ranged from 93% (As) to 100% (Pb) for elements 78–98% for organochlorine pesticide residues (OCPs) at 100 ng mL?1. According to the results, lead, cadmium, and pesticides were not detected in any of the samples, while arsenic was detected in 16 samples. 相似文献
13.
Tatsumi Ishihara Kuninobu Shimose Takanari Kudo Hiroyasu Nishiguchi Taner Akbay Yusaku Takita 《Journal of the American Ceramic Society》2000,83(8):1921-1927
A yttria-stabilized zirconia (YSZ) thin film on an La0.8 Sr0.2 MnO3 porous cathode substrate was prepared, using electrophoretic deposition (EPD) to fabricate a solid oxide fuel cell (SOFC). The electrical conductivity of an La0.8 Sr0.2 MnO3 substrate is satisfactorily high at room temperature; therefore, YSZ powder could be deposited electrophoretically onto an La0.8 Sr0.2 MnO3 substrate without any extra surface treatment, such as a metal coating. Successive repetition of EPD and sintering was required to obtain a film without gas leakage, because of the thermal expansion coefficient mismatch between the YSZ and the La0.8 Sr0.2 MnO3 substrate. On the other hand, the electromotive force of the oxygen concentration in the cell that used YSZ film prepared via EPD increased and attained the theoretical value when the number of deposition and calcination cycles was increased. Six or more successive repetitions were required to obtain a YSZ film without gas leakage. A planar-type SOFC was fabricated, using nickel as the anode and YSZ film (∼10 μm thick) that had been deposited onto the La0.8 Sr0.2 MnO3 substrate as the electrolyte and cathode. The cell exhibited an open circuit voltage of 1.0 V and a maximum power density of 1.5 W/cm2 . Thus, the EPD method could be used as a colloidal process to prepare YSZ thin-film electrolytes for SOFCs. 相似文献
14.
M. Taner Eskil 《Machine Vision and Applications》2014,25(7):1825-1840
In particle filtering, dimensionality of the state space can be reduced by tracking control (or feature) points as independent objects, which are traditionally named as partitions. Two critical decisions have to be made in implementation of reduced state-space dimensionality. First is how to construct a dynamic (transition) model for partitions that are inherently dependent. Second critical decision is how to filter partition states such that a viable and likely object state is achieved. In this study, we present a correlation-based transition model and a proposal function that incorporate partition dependency in particle filtering in a computationally tractable manner. We test our algorithm on challenging examples of occlusion, clutter and drastic changes in relative speeds of partitions. Our successful results with as low as 10 particles per partition indicate that the proposed algorithm is both robust and efficient. 相似文献
15.
铝合金半固态浆料中球形颗粒的演变 总被引:1,自引:0,他引:1
Yucel BIROL 《中国有色金属学会会刊》2013,23(1):1-6
用AlSi7Mg0.6半固态浆料进行实验,研究球形颗粒的演变机理.在略高于液相线温度下水淬的样品中结晶相主要为枝晶,而采用旋转圆筒的方式来搅拌熔体使其冷却到半固态温度范围内时样品的结晶相完全球化.在铸造前进行较长时间的内冷却和搅拌,可以得到较高的固相分数.不同大小的枝晶碎片的存在表明,在搅拌过程中,初始的固相分数形成后不再受冷却的影响. 相似文献
16.
The values of bond dissociation energies, BDE, of the weakest N–N bonds and total energies, Etotal, of molecules have been calculated for 14 cyclic nitramines by means of the UB3LYP/6-31G? and UB3LYP/6-31 + G? // PM3 methods. The relationships found between the BDE values and logarithms of impact sensitivity of these nitramines, expressed as drop energy, Edr, are not unambiguous. Replacement of these BDE values by the BDE/Etotal ratio has not resulted in any simplification of the said relationships, but their quality improved, particularly with application of the UB3LYP/6-31 + G? // PM3 (UHF) method. The reason of ambiguity of the relationships found mainly lies in real conformation of the respective molecules and intermolecular force effects in real molecular crystals, which are included in neither of the two calculation methods. 相似文献
17.
Tolga Taner Mecit Sivrioğlu Hüseyin Topal Ahmet Selim Dalkılıç Somchai Wongwises 《Sadhana》2018,43(3):42
This study presents a case study of energy management in a sugar factory in Turkey. The main idea of the study is to analyse energy consumption, the quantity of material production, and figure out a suitable energy efficiency for the case study of a sugar factory subsequently. Firstly, a material production and energy consumption audit were performed for the sugar factory. Secondly, energy efficiency was calculated from the energy data. The SPSS (Statistical Package for the Social Sciences) statistical software was used to ensure the accuracy of the data. The factory’s energy consumption was calculated as 43,590.25 toe (tons of oil equivalent) over the last year. These results were used for CUSUM (Cumulative Sum Deviation Method) graphics. This research poses the consumption of energy, cost of energy and the relationship between energy usage and material production of sugar. The unit of energy cost was 688.22 [$/toe] for the last year. This result showed that the factory decreased the unit of energy by optimisation. The results indicated that the investigated sugar factory should pay attention to the energy management issue in order to comply with the Energy Efficiency of Turkish Law and Directives. 相似文献
18.
High-temperature abrasive wear testing of potential tool materials for thixoforming of steels 总被引:1,自引:0,他引:1
Yucel Birol 《Tribology International》2010,43(11):2222-286
High temperature abrasive wear performance of Inconel 617, Stellite 6 alloys and X32CrMoV33 hot work tool steel was investigated. The wear resistance of the latter is degraded at 750 °C due to its inferior oxidation resistance. Extensive oxidation co-occuring with abrasive wear at 750 °C leads to substantial material loss due to the lack of a protective oxide scale, sufficiently ductile to sustain the abrasion without extensive spalling. The wear resistance of the Inconel 617 and Stellite 6 alloys, on the other hand, improves at 750 °C owing to protective oxides that sustain the abrasion without spalling. 相似文献
19.
Multivariate extensions of well-known linear mixed-effects models have been increasingly utilized in inference by multiple imputation in the analysis of multilevel incomplete data. The normality assumption for the underlying error terms and random effects plays a crucial role in simulating the posterior predictive distribution from which the multiple imputations are drawn. The plausibility of this normality assumption on the subject-specific random effects is assessed. Specifically, the performance of multiple imputation created under a multivariate linear mixed-effects model is investigated on a diverse set of incomplete data sets simulated under varying distributional characteristics. Under moderate amounts of missing data, the simulation study confirms that the underlying model leads to a well-calibrated procedure with negligible biases and actual coverage rates close to nominal rates in estimates of the regression coefficients. Estimation quality of the random-effect variance and association measures, however, are negatively affected from both the misspecification of the random-effect distribution and number of incompletely-observed variables. Some of the adverse impacts include lower coverage rates and increased biases. 相似文献
20.
Amiodarone decreases plasma and tissue triiodothyronine (T3) and increases plasma cholesterol levels resembling changes seen during hypothyroidism. To elucidate the mechanism of amiodarone-induced hypercholesterolemia we investigated gene expression of three key proteins in cholesterol metabolism (cholesterol 7 alpha-hydroxylase, LDL receptor, HMG-CoA reductase) in livers of rats. Animals were treated with amiodarone or propylthiouracil (to induce mild hypothyroidism). The LDL receptor mRNA was downregulated (approximately 50%) in both amiodarone-treated and hypothyroid animals, while the other mRNA remained unchanged after 14-day treatment. The results suggest that amiodarone-induced hypercholesterolemia is associated with decreased LDL receptor mRNA levels. 相似文献