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排序方式: 共有106条查询结果,搜索用时 15 毫秒
41.
Shuyan Shao Jian Liu Giuseppe Portale Hong‐Hua Fang Graeme R. Blake Gert H. ten Brink L. Jan Anton Koster Maria Antonietta Loi 《Liver Transplantation》2018,8(4)
The low power conversion efficiency (PCE) of tin‐based hybrid perovskite solar cells (HPSCs) is mainly attributed to the high background carrier density due to a high density of intrinsic defects such as Sn vacancies and oxidized species (Sn4+) that characterize Sn‐based HPSCs. Herein, this study reports on the successful reduction of the background carrier density by more than one order of magnitude by depositing near‐single‐crystalline formamidinium tin iodide (FASnI3) films with the orthorhombic a‐axis in the out‐of‐plane direction. Using these highly crystalline films, obtained by mixing a very small amount (0.08 m ) of layered (2D) Sn perovskite with 0.92 m (3D) FASnI3, for the first time a PCE as high as 9.0% in a planar p–i–n device structure is achieved. These devices display negligible hysteresis and light soaking, as they benefit from very low trap‐assisted recombination, low shunt losses, and more efficient charge collection. This represents a 50% improvement in PCE compared to the best reference cell based on a pure FASnI3 film using SnF2 as a reducing agent. Moreover, the 2D/3D‐based HPSCs show considerable improved stability due to the enhanced robustness of the perovskite film compared to the reference cell. 相似文献
42.
Metallic tin powder, injected into Lewis rats obtained from three different sources, caused enlargement of the regional draining
lymph nodes. The histopathology featured epithelioid cell granulomas around phagocytosed particles of tin and an intense hyperplasia
of plasma cells. The same material injected into August rats enlarged the lymph nodes but the enlargement was caused by granulomas
without a major concomitant plasma cell response. In most other strains, tin produced less lymph node enlargement and the
plasma cell response was minimal. However, F1 hybrids of Lewis rats with either the August, Brown-Norway (BN), or Dark Agouti
(DA) strains developed plasma cell hyperplasia similar to that seen in the parental Lewis strain. The response to tin was
the same whether the tin was injected into the feet or into the peritoneal cavity. Thus, the lymph node response to metallic
tin varied from a slight, banal response to insoluble foreign particles, to an exuberant granulomatous hyperplasia, to an
intense plasmacellular hyperplasia, depending on the genetic characteristics of the subjects. 相似文献
43.
Joseph J. Cooney 《Journal of industrial microbiology & biotechnology》1988,3(4):195-204
Summary The use of organotins for agricultural and industrial purposes and in the marine environment has been increasing steadily for more than 20 years. Recently, reliable methodologies have been developed to permit quantification of individual molecular species of organotins in cultures and in the environment. Particular attention has been given to methyltins which can be formed abiotically and by microorganisms, and to tributyltins which are toxic components of effective antifouling paints. In the aquatic environment tin, tributyltins and other organotins accumulate in the surface microlayer, in sediments, and on suspended particulates. Tin compounds are toxic to a variety of organisms and some aquatic organisms can bioaccumulate them. When tin compounds, particularly di-or tri-substituted tins, enter an ecosystem, a portion of the microbial population is killed. Among the survivors are organisms which can methylate inorganic or organic tins, but the relative contribution of biotic and abiotic mechanisms is not clear. While many details of methylations and demethylations need to be worked out, it is clear that transformations of tins can influence the toxicity, volatility and mobility of tin in natural ecosystems. Tributyltins can be debutylated by microorganisms, and hydroxybutyl tins may be intermediates, as they are in mammalian systems. Little is known of the potential and probable microbial transformations of other economically important organotins, but the transformations should be studied for they may have industrial and environmental importance. 相似文献
44.
45.
Richard Y. Morita 《Geomicrobiology journal》2013,30(2):101-102
Mixed cultures derived from Boston Harbor sediments, which gave evidence of methylating tin compounds, yielded two isolates, each a Bacillus sp., which methylated CH3SnCl3 to form (CH3)3SnX in coculture. Neither organism alone gave evidence of methylation. SnCl4 and (CH3)2SnCl2 were not methylated. Transfer of either organism to filtered medium containing CH3SnCl3 in which the other had grown did not lead to methylation. Therefore methylation by the coculture is not simply a matter of cross‐feeding. 相似文献
46.
本文对鲜蕨菜经冷冻、盐腌、罐藏二种方式保藏后的营养素进行测定,结果认为,冷冻是较理想的保藏方法。 相似文献
47.
Dariusz Man 《Journal of liposome research》2013,23(3):225-234
The kinetics of change in the fluidity of liposome membranes, obtained in the process of sonication of Egg Yolk Lecithin (EYL), with the admixture of organic tin compounds, was investigated. Five compounds were selected for the research: three differed in the length of hydrocarbon chains, (CH3)4Sn, (C2H5)4Sn, and (C3H7)3SnCl, whereas two differed in the number of aromatic rings, (C6H5)2SnCl2 and (C6H5)3SnCl. The concentration of the compounds in proportion to EYL was 2 mol-%. Electron Spin (paramagnetic) Resonance (ESR) was applied using two spin probes TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) and 16-DOXYL-stearic acid methyl ester (2-ethyl-2-(15-methoxy-15-oxopentadecyl)-4,4-dimethyl-3-oxazolidinyloxyl) localized at different sites within the membrane, to determine the spectroscopic parameters: partition (F) and rotation correlation time (τ), related to the membrane's fluidity. The ESR spectroscopic spectra of investigated samples were recorded from the moment of introducing the admixture to membranes for 180h. Analysing the obtained results, the following conclusions can be drawn: chain compounds slightly stiffened the membrane both on the inside (hydrophobic) layer and on the surface one, whereas ring compounds resulted in fluidization of the membrane—stronger in the case of the two-layer middle and weaker with reference to the surface layer. 相似文献
48.
Zhongxue Chen Min Zhou Yuliang Cao Xinping Ai Hanxi Yang Jun Liu 《Liver Transplantation》2012,2(1):95-102
A simple ball‐milling method is used to synthesize a tin oxide‐silicon carbide/few‐layer graphene core‐shell structure in which nanometer‐sized SnO2 particles are uniformly dispersed on a supporting SiC core and encapsulated with few‐layer graphene coatings by in situ mechanical peeling. The SnO2‐SiC/G nanocomposite material delivers a high reversible capacity of 810 mA h g?1 and 83% capacity retention over 150 charge/discharge cycles between 1.5 and 0.01 V at a rate of 0.1 A g?1. A high reversible capacity of 425 mA h g?1 also can be obtained at a rate of 2 A g?1. When discharged (Li extraction) to a higher potential at 3.0 V (vs. Li/Li+), the SnO2‐SiC/G nanocomposite material delivers a reversible capacity of 1451 mA h g?1 (based on the SnO2 mass), which corresponds to 97% of the expected theoretical capacity (1494 mA h g?1, 8.4 equivalent of lithium per SnO2), and exhibits good cyclability. This result suggests that the core‐shell nanostructure can achieve a completely reversible transformation from Li4.4Sn to SnO2 during discharging (i.e., Li extraction by dealloying and a reversible conversion reaction, generating 8.4 electrons). This suggests that simple mechanical milling can be a powerful approach to improve the stability of high‐performance electrode materials involving structural conversion and transformation. 相似文献
49.
50.
J. L. Greger Sylvia A. Smith Mary Ann Johnson Margaret J. Baier 《Biological trace element research》1982,4(4):269-278
The main purpose of these studies was to determine whether the amounts of tin and aluminum that can enter foods during processing
and storage are sufficient to affect the utilization of selenium by human subjects. Two 40-day balance studies were conducted.
The eight adult males who participated in the first study lost significantly more selenium in their feces when fed a test
diet containing 50 mg tin daily than when fed the control diet containing 0.1 mg tin daily. During the first study subjects
tended to excrete less selenium in the urine when fed the test diet rather than the control diet. In the second study, the
dietary treatments (5 and 125 mg aluminum daily) had no effect on the excretion and apparent retention of selenium by eight
adult males. 相似文献