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101.
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
102.
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
103.
104.
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
105.
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
106.
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
107.
三尖瓣关闭不全对上腔静脉血流速度频谱的影响 总被引:3,自引:0,他引:3
目的探讨不同程度三尖瓣关闭不全对上腔静脉血流速度频谱的影响。方法随机选取三尖瓣关闭不全病例60例及健康对照20例,在胸骨旁四腔或心尖四腔切面测量三尖瓣返流面积与右心房面积之比确定返流程度。经右侧锁骨上窝探查上腔静脉血流速度频谱,记录3个呼吸周期的频谱曲线,观察其形态,计算各参数的呼吸变化率。结果三尖瓣轻度及中度关闭不全时,上腔静脉血流频谱参数的呼吸变化率与对照组无显著差异(P〉0.05),且上腔静脉频谱形态无明显变化(P〉0.05);三尖瓣重度关闭不全时,上腔静脉频谱参数S、D波的呼吸变化率较对照组明显减低,而VR、AR波增高(P〈0.05),部分患者频谱形态发生变化。结论上腔静脉频谱参数的呼吸变化率随三尖瓣返流程度加重而改变,重度三尖瓣返流会引起上腔静脉频谱形态变化。 相似文献
108.
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
109.
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)
110.