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31.
Wenyuan Duan Yanlin Li Yeming He Duqiang Xin Najeeb ur Rehman Lashari Cheng Ma Yuzhen Zhao Zongcheng Miao 《RSC advances》2022,12(34):22244
Aqueous rechargeable lithium-ion batteries (ARLBs) are regarded as a competitive challenger for large-scale energy storage systems because of their high safety, modest cost, and green nature. A kind of modified composite material composed of H2V3O8 nanorods and graphene sheets (HVO/G) has been effectively made by a one-step hydrothermal method and following calcination at 523 K. XRD, SEM, TEM, and TG are used to determine the phase structures and morphologies of the composite materials. Owing to the advantage of the layered structure of H2V3O8 nanorods, the excellent conductivity of the graphene sheets, and the 3D network structure of the modified composite, the ARLBs with HVO/G can deliver an adequate specific capacity of 271 mA h g−1 at 200 mA g−1 and have a retention rate of 73.4% after 50 cycles. The average discharge capacity of ARLB with HVO/G as anode has a considerable improvement over that of HVO/CNTs and HVO, whatever the current rate used. Moreover, we find that the diffusion coefficient of lithium-ion increases by an order of magnitude through the theoretical calculation for HVO/G ARLB. The new ARLB with HVO/G electrode is a potential energy storage system with great advantages, such as simple preparation, easy assembly process, excellent safety and low-cost environmental protection.Aqueous rechargeable lithium-ion batteries (ARLBs) are regarded as a competitive challenger for large-scale energy storage systems because of their high safety, modest cost, and green nature. 相似文献
32.
Dan-Dan Xia Hao-Jie Duan Fei Xie Tian-Peng Xie Yan Zhang Yue Sun Jian-Mei Lu Yu-Hong Gao Hao Zhou Zhong-Tao Ding 《RSC advances》2022,12(34):22295
Five previously undescribed epoxy octa-hydronaphthalene polyketides, altereporenes A–E (1–5) were isolated from rice culture of the endophytic fungus Alternaria sp. YUD20002 derived from the tubers of Solanum tuberosum. Their structures were determined on the basis of comprehensive spectroscopic analyses, while the absolute configurations were elucidated by the comparison of experimental and calculated specific rotations. Meanwhile, the antimicrobial, cytotoxic, anti-inflammatory and acetylcholinesterase inhibitory activities of compounds 1–5 were also investigated.Five previously undescribed epoxy octa-hydronaphthalene polyketides, altereporenes A–E (1–5) were isolated from rice culture of the endophytic fungus Alternaria sp. YUD20002 derived from the tubers of Solanum tuberosum. 相似文献
33.
Sedoreoviridae is a family of viruses belonging to the order Reovirales and comprises six genera, two of which, Orbivirus and Seadornavirus, contain arboviruses that cause disease in humans and livestock. Areas such as Yunnan Province in southwestern China, have high arboviral activity due in part to warm and wet summers, which support high populations of biting flies such as mosquitoes and Culicoides. Three viral isolates previously obtained from Culicoides collected at cattle farms in Shizong County of Yunnan Province, China, between 2019 and 2020 were completely sequenced and identified as Banna virus (BAV) genotype A of Seadornavirus and serotypes 1 and 7 of epizootic hemorrhagic disease virus (EHDV) of Orbivirus. These results suggest that Culicoides tainanus and C. orientalis are potential vectors of BAV and EHDV, respectively, and represent the first association of a BAV with C. tainanus and of an arbovirus with C. orientalis. Analysis using VP9 generally agreed with the current groupings within this genus based on VP12, although the classification for some strains should be corrected. Furthermore, the placement of Kadipiro virus (KDV) and Liao ning virus (LNV) in Seadornavirus may need confirmation as phylogenetic analysis placed these viruses as sister to other species in the genus. 相似文献
34.
Enshuai Wang Fei Yang Xinmin Shen Haiqin Duan Xiaonan Zhang Qin Yin Wenqiang Peng Xiaocui Yang Liu Yang 《Materials》2022,15(10)
An acoustic metamaterial absorber of parallel–connection square Helmholtz resonators is proposed in this study, and its sound absorption coefficients are optimized to reduce the noise for the given conditions in the factory. A two–dimensional equivalent simulation model is built to obtain the initial value of parameters and a three–dimensional finite element model is constructed to simulate the sound absorption performance of the metamaterial cell, which aims to improve the research efficiency. The optimal parameters of metamaterial cells are obtained through the particle swarm optimization algorithm, and its effectiveness and accuracy are validated through preparing the experimental sample using 3D printing and measuring the sound absorption coefficient by the standing wave tube detection. The consistency between the experimental data and simulation data verifies feasibility of the proposed optimization method and usefulness of the developed acoustic metamaterial absorber, and the desired sound absorption performances for given conditions are achieved. The experimental results prove that parallel–connection square Helmholtz resonators can achieve an adjustable frequency spectrum for the low frequency noise control by parameter optimization, which is propitious to promote its application in reducing the noise in the factory. 相似文献
35.
目的探讨心力衰竭对门静脉频谱形态的影响,摸索超声检查评价心功能的新途径。方法选取临床Ⅰ~Ⅲ度心力衰竭患者60例,按心衰竭程度分组,每组各20例;健康对照组20例。排除肝脏及门静脉、下腔静脉病变。经右侧肋间及剑突下探查门静脉,在取得门静脉清晰二维切面图像后,记录1~3个呼吸周期中的门静脉频谱,观察频谱形态,记录各组不同门静脉频谱形态的例数,所获资料采用统计软件SPSS11.0处理。结果健康对照组门静脉频谱均表现为单向连续频谱,各心力衰竭组出现不同程度的门静脉收缩末期反向血流,Ⅲ度心力衰竭组门静脉频谱多出现恒定的收缩末期反向血流。结论心力衰竭可导致门静脉频谱形态异常,观察门静脉频谱形态,可作为判断心力衰竭程度的辅助依据。 相似文献
36.
Xinxia Zhang Wen Duan Wenbin Wei Bijuan Kuang Yunqi Zhang Xiangguang Xu Xuesong HuDepartment of Cardiology Shenzhen Futian Hospital Affiliated of Guangdong Medical College Shenzhen China 《岭南心血管病杂志(英文版)》2007,8(3):133-134
Objectives To investigate the change and clinical significance of clopidogrel on platelet membrane CD40L in coronary artery disease patients before and after percutaneous coronary intervention(PCI). Methods 30 cases who were diagnosis coronary artery diseases(CAD) by coronary angiography, mean age 56±9 years old. All the patients who had no antiplatelet aggregation contraindication, were treated with standard anti angina pectoris drugs. Before PCI, all the patients took clopidogrel 75 mg per day. Activated platelet membrane CD40L express rate was measured by flow cytometry before and after PCI 6 hours. Results Activated platelet membrane CD40L express rate were 3.73±2.15 and 2.46±0.90, respectively in 30 patients before and after PCI 6 hours. Activated platelet membrane CD40L express rate was significantly decrease after PCI 6 hours than that before PCI(P<0.01). Conclusions Clopidogrel has significance effect on platelet membrane CD40L in coronary artery disease patients undergoing PCI. Clopidogrel can suppression platelet activation and prevent thromboembolism event occurrence. 相似文献
37.
Yang Gao Jishuai Cheng Xingli Xu Xueqi Li Jingjing Zhang Danjing Ma Guorun Jiang Yun Liao Shengtao Fan Zhenye Niu Rong Yue Penglan Chang Fengyuan Zeng Suqin Duan Ziyan Meng Xiangxiong Xu Xinghang Li Dandan Li Li Yu Lifen Ping Heng Zhao Mingtian Guo Lichun Wang Yafang Wang Ying Zhang Qihan Li 《Viruses》2022,14(5)
38.
Isoflavonoids from Astragalus mongholicus protect PC12 cells from toxicity induced by L-glutamate 总被引:5,自引:0,他引:5
lsoflavonoids, formononetin, 9,10-dimethoxypterocarpan 3-O-beta-D-glucoside, ononin, calycosin 7-O-glc and calycosin, were isolated from the roots of Astragalus mongholicus Bunge (Leguminosae). The neuroprotective roles and direct antioxidant effects of these isoflavonoids were investigated by using PC12 cell model and DPPH (1,1-diphenyl-2-picrylhydrazyl) assay. Formononetin, ononin and calycosin were found inhibiting glutamate-induced cell injury, with an estimated 50% effective concentration (EC50) of 0.027 microg/ml, 0.047 microg/ml and 0.031 microg/ml, respectively. Pretreatment with them increased the activities of antioxidant enzymes, including superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and prevented the release of lactate dehydrogenase (LDH) in glutamate-injured PC12 cells. On the other hand, calycosin 7-O-glc and calycosin showed more scavenging activity to DPPH radicals than formononetin in the cell-free system. The inconsistency between the neuroprotective capabilities of isoflavonoids and their directly scavenging activity to DPPH radicals indicated that formononetin, ononin and calycosin probably depended on increasing endogenous antioxidant and stabilizing the cells' membrane structures to inhibit the cell damage induced by glutamate. 相似文献
39.
目的:探讨芍甘多苷对CCl4,亚急性肝损伤大鼠血清转氨酶、肝脏病理及肝细胞线粒体保护作用.方法:采用CCl4,诱发大鼠亚急性肝损伤,然后灌胃给予不同剂量的芍甘多苷治疗,观察药物对血清ALT,AST,肝脏组织病理,肝细胞线粒体超微结构和ATPase,MDA,SOD的影响.结果:芍甘多苷对CCl4诱发大鼠亚急性肝损伤升高的转氨酶有明显的降低作用,并使形态学上的肝细胞变性和坏死得到明显改善和恢复,能提高线粒体Na+-K+-ATPase,Ca2+-ATPase活性,降低线粒体MDA含量,升高SOD活性,改善线粒体超微病理变化,降低肝细胞线粒体截面面积、周长、等效直径、平均吸光度.结论:芍甘多苷有明显的肝脏保护作用,其机制与减轻线粒体损伤有关. 相似文献
40.
目的:了解山东中医药大学附属医院近年来引进的博士研究生的发展现状。方法:采用调查问卷的方法对医院近年来引进且入院满1年的博士研究生进行调查,统计其入院后的科研产出及工作状况,通过内容分析法分析其工作以来遇到的问题及困惑。结果:缺少科研支持、职能部门管理不到位、科室管理不够科学等是造成博士研究生发展困惑的因素,医院在高层次人才培养意识、高层次人才培养机制、高层次人才科研支持力度、对引入的外校高层次人才的人文关怀与心理疏导方面存在不足。结论:医院应增强高层人才培养的意识、健全人才培养的机制、强化人才培养与梯队建设方案的落实监督、为高层次人才提供科研支持、增强对引进高层次人才的人文关怀与心理疏导等,改变高层次人才发展环境。 相似文献