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51.
Sulfur‐Impregnated,Sandwich‐Type,Hybrid Carbon Nanosheets with Hierarchical Porous Structure for High‐Performance Lithium‐Sulfur Batteries 下载免费PDF全文
Xi'an Chen Zhubing Xiao Xutao Ning Zheng Liu Zhi Yang Chao Zou Shun Wang Xiaohua Chen Ying Chen Shaoming Huang 《Liver Transplantation》2014,4(13)
Sandwich‐type hybrid carbon nanosheets (SCNMM) consisting of graphene and micro/mesoporous carbon layer are fabricated via a double template method using graphene oxide as the shape‐directing agent and SiO2 nanoparticles as the mesoporous guide. The polypyrrole synthesized in situ on the graphene oxide sheets is used as a carbon precursor. The micro/mesoporous strcutures of the SCNMM are created by a carbonization process followed by HF solution etching and KOH treatment. Sulfur is impregnated into the hybrid carbon nanosheets to generate S@SCNMM composites for the cathode materials in Li‐S secondary batteries. The microstructures and electrochemical performance of the as‐prepared samples are investigated in detail. The hybrid carbon nanosheets, which have a thickness of about 10–25 nm, high surface area of 1588 m2 g?1, and broad pore size distribution of 0.8–6.0 nm, are highly interconnected to form a 3D hierarchical structure. The S@SCNMM sample with the sulfur content of 74 wt% exhibits excellent electrochemical performance, including large reversible capacity, good cycling stability and coulombic efficiency, and good rate capability, which is believed to be due to the structure of hybrid carbon materials with hierarchical porous structure, which have large specific surface area and pore volume. 相似文献
52.
从江浙蝮蛇中分离纯化的碱性磷脂酶A2在pH9.5,0.05mmol/LCHES缓冲液中,用汽相悬滴扩散的方法,获得了适用于高分辨率X射线结构分析的单晶.经X200B面探测器分析,表明该晶体属于正交晶系,P2I2I2I空间群,晶胞参数为a=97.13,b=103.69,c=23.27.并收集了一套衍射数据,独立衍射点数12001个,数据完整度为86.2%,Rmerge为0.0459.最高分辨率达2.0,根据分子量与晶胞体积估算,一个不对称单位含两个分子. 相似文献
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iQPR技术处理污水是一项新型尖端的技术,此技术可以成功降低污水乃至受到污染的地下水中的各种污染指标。但是,iQPR技术处理污水尤其是地下水是否存在潜在的生物安全性问题有待于进一步研究。因此,为评估iQPR技术对生物安全性的影响,本研究首先分析了三种不同iQPR法处理水的水质成分;其次系统研究了iQPR水对SD鼠在个体水平、组织水平和病理形态学损伤的研究。研究表明:iQPR处理的水质成分较对照组普通饮用水好,在个体组织水平检测未见异常,尽管其中一组iQPR处理水造成了SD鼠的脾小体增大,但是可能的原因是水处理环节存在微生物污染现象,因此,初步认定此技术未造成SD大鼠的个体损伤。本研究为揭示iQPR处理的水对生物体的安全性评价提供一个理论依据。 相似文献
56.
Zheng Zhou Jiajun Wu Wenli Ma Feilin Dong Jiafeng Wang 《Journal of cellular and molecular medicine》2023,27(2):204
Necroptosis is a unique programmed death mechanism of necrotic cells. However, its role and specific mechanism in cancer remain unclear, and a systematic pan‐cancer analysis of necroptosis is yet to be conducted. Thus, we performed a specific pan‐cancer analysis using The Cancer Genome Atlas and Genotype‐Tissue Expression databases to analyse necroptosis expression in terms of cancer prognosis, DNA methylation status, tumour mutative burden, microsatellite instability, immune cell infiltration in different types of cancer and molecular mechanisms. For the first time, we explored the correlation between necroptosis and immunotherapy prognosis. Thus, our study provides a relatively comprehensive understanding of the carcinogenicity of necroptosis in different types of cancer. It is suggested that necroptosis can be used to evaluate the sensitivity of different patients to immunotherapy and may become a potential target for tumour immunotherapy. 相似文献
57.
Dun Wang Xiao‐Fei Li Zheng‐Jian Zhou Xu‐Ping Feng Wan‐Jun Yang De‐An Jiang 《Physiologia plantarum》2010,139(1):55-67
Studies on some plant species have shown that increasing the growth temperature gradually or pretreating with high temperature can lead to obvious photosynthetic acclimation to high temperature. To test whether this acclimation arises from heat adaptation of ribulose 1,5‐bisphosphate carboxylase/oxygenase (Rubisco, EC 4.1.1.39) activation mediated by Rubisco activase (RCA), gene expression of RCA large isoform (RCAL) and RCA small isoform (RCAS) in rice was determined using a 4‐day heat stress treatment [40/30°C (day/night)] followed by a 3‐day recovery under control conditions [30/22°C (day/night)]. The heat stress significantly induced the expression of RCAL as determined by both mRNA and protein levels. Correlative analysis indicated that RCAS protein content was extremely significantly related to Rubisco initial activity and net photosynthetic rate (Pn) under both heat stress and normal conditions. Immunoblot analysis of the Rubisco–RCA complex revealed that the ratio of RCAL to Rubisco increased markedly in heat‐acclimated rice leaves. Furthermore, transgenic rice plants expressing enhanced amounts of RCAL exhibited higher thermotolerance in Pn and Rubisco initial activity and grew better at high temperature than wild‐type (WT) plants and transgenic rice plants expressing enhanced amounts of RCAS. Under normal conditions, the transgenic rice plants expressing enhanced amounts of RCAS showed higher Pn and produced more biomass than transgenic rice plants expressing enhanced amounts of RCAL and wild‐type plants. Together, these suggest that the heat‐induced RCAL may play an important role in photosynthetic acclimation to moderate heat stress in vivo, while RCAS plays a major role in maintaining Rubisco initial activity under normal conditions. 相似文献
58.
Chiakang Ho Ya Gao Danning Zheng Yanjun Liu Shengzhou Shan Bin Fang Yixuan Zhao Dingzhong Song Yifan Zhang Qingfeng Li 《Journal of cellular and molecular medicine》2019,23(8):5108-5118
Obesity and its associated metabolic disorders such as diabetes, hepatic steatosis and chronic heart diseases are affecting billions of individuals. However there is no satisfactory drug to treat such diseases. In this study, we found that alisol A, a major active triterpene isolated from the Chinese traditional medicine Rhizoma Alismatis, could significantly attenuate high‐fat‐diet‐induced obesity. Our biochemical detection demonstrated that alisol A remarkably decreased lipid levels, alleviated glucose metabolism disorders and insulin resistance in high‐fat‐diet‐induced obese mice. We also found that alisol A reduced hepatic steatosis and improved liver function in the obese mice model.In addition, protein expression investigation revealed that alisol A had an active effect on AMPK/ACC/SREBP‐1c pathway. As suggested by the molecular docking study, such bioactivity of alisol A may result from its selective binding to the catalytic region of AMPK.Therefore, we believe that Alisol A could serve as a promising agent for treatment of obesity and its related metabolic diseases. 相似文献
59.
Chen Z Zheng Z Huang H Song Y Zhang X Ma J Wang B Zhang C Ju J 《Bioorganic & medicinal chemistry letters》2012,22(9):3332-3335
Three new mycophenolic acid derivatives, penicacids A-C (1-3), together with two known analogues, mycophenolic acid (MPA, 4) and 4'-hydroxy-MPA (5), were isolated from a fungus Penicillium sp. SOF07 derived from a South China Sea marine sediment. The structures of compounds 1-3 were elucidated on the basis of MS and NMR ((1)H, (13)C, HSQC and HMBC) data analyses and comparisons with the known compounds. Structure-activity relationship studies of compounds 1-5 focused on inosine-monophosphate dehydrogenase inhibition revealed that hydroxylation at C-4', methylation at C-7-OH, dual hydroxylation at C-2'/C-3' double bond of MPA diminished bioactivity whereas glucosyl hydroxylation at C-4' correlated to bioactivity comparable to that observed for MPA. 相似文献
60.
Lack of enhanced spinal regeneration in Nogo-deficient mice 总被引:37,自引:0,他引:37
The failure of regeneration of severed axons in the adult mammalian central nervous system is thought to be due partly to the presence of endogenous inhibitors of axon regeneration. The nogo gene encodes three proteins (Nogo-A, -B, and -C) that have been proposed to contribute to this inhibition. To determine whether deletion of nogo enhances regenerative ability, we generated two lines of mutant mice, one lacking Nogo-A and -B but not -C (Nogo-A/B mutant), and one deficient in all three isoforms (Nogo-A/B/C mutant). Although Nogo-A/B-deficient myelin has reduced inhibitory activity in a neurite outgrowth assay in vitro, tracing of corticospinal tract fibers after dorsal hemisection of the spinal cord did not reveal an obvious increase in regeneration or sprouting of these fibers in either mouse line, suggesting that elimination of Nogo alone is not sufficient to induce extensive axon regeneration. 相似文献