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991.
通过对7种国产贝母属(Fritillaria)植物的染色体核型进行观察和研究,报道了小白花贝母(F.albidoflora Duan&Zheng)、川贝母(F.cirrhosa Don)、伊贝母(F.pallidiflora Schrenk ex Fischer&Meyer)、华西贝母(F.sichuanica Chen)、托里贝母(F.tortifolia Duan&Zheng)、新疆贝母(F.walujewii Regel)、裕民贝母(F.yuminensis Duan)等7种植物的染色体数目及核型,其中3种为首次报道。结果显示,7种国产贝母属植物的核型均具有高度不对称性。此外,小白花贝母与已报道的黄花贝母(F.verticillata Willdenow)的核型存在明显差异,提示Flora of China将小白花贝母归并入黄花贝母的分类处理可能并不恰当,二者的关系需进一步研究。 相似文献
992.
Fayu Yang Xianglian Ge Xiubin He Xiexie Liu Chenchen Zhou Huihui Sun Junsong Zhang Junzhao Zhao Zongming Song Jia Qu Changbao Liu Feng Gu 《遗传学报》2018,45(6):329-332
正CRISPR/Cas9-mediated genome engineering technologies are now widely applied in various organisms,including mouse and human cells(Cong et al.,2013;Mali et al.,2013;Yang et al.,2013;Hsu et al.,2014).The most widely used customized CRISPR/Cas9(Sp Cas9)is derived from Streptococcus pyogenes(Cong et al.,2013).The CRISPR/Cas9 system creates site-specific double- 相似文献
993.
Germanium Thin Film Protected Lithium Aluminum Germanium Phosphate for Solid‐State Li Batteries 下载免费PDF全文
Yijie Liu Chao Li Bojie Li Hucheng Song Zhu Cheng Minrui Chen Ping He Haoshen Zhou 《Liver Transplantation》2018,8(16)
Solid‐state Li batteries using Na+ superionic conductor type solid electrolyte attracts wide interest because of its safety and high theoretical energy density. The NASCION type solid electrolyte LAGP (Li1.5Al0.5Ge0.5P3O12) shows favorable conductivity as well as good mechanical strength to prevent Li dendrite penetration. However, the instability of LAGP with Li metal remains a great challenge. In this work, an amorphous Ge thin film is sputtered on an LAGP surface, which can not only suppress the reduction reaction of Ge4+ and Li, but also produces intimate contact between the Li metal and the LAGP solid electrolyte. The symmetric cell with the Ge‐coated LAGP solid electrolyte shows superior stability and cycle performance for 100 cycles at 0.1 mA cm?2. A quasi‐solid‐state Li–air battery has also been assembled to further demonstrate this advantage. A stable cycling performance of 30 cycles in ambient air can be obtained. This work helps to achieve a stable and ionic conducting interface in solid‐state Li batteries. 相似文献
994.
Sodium Ion Stabilized Vanadium Oxide Nanowire Cathode for High‐Performance Zinc‐Ion Batteries 下载免费PDF全文
Pan He Guobin Zhang Xiaobin Liao Mengyu Yan Xu Xu Qinyou An Jun Liu Liqiang Mai 《Liver Transplantation》2018,8(10)
Aqueous Zn‐ion batteries (ZIBs) have received incremental attention because of their cost‐effectiveness and the materials abundance. They are a promising choice for large‐scale energy storage applications. However, developing suitable cathode materials for ZIBs remains a great challenge. In this work, pioneering work on the designing and construction of aqueous Zn//Na0.33V2O5 batteries is reported. The Na0.33V2O5 (NVO) electrode delivers a high capacity of 367.1 mA h g?1 at 0.1 A g?1, and exhibits long‐term cyclic stability with a capacity retention over 93% for 1000 cycles. The improvement of electrical conductivity, resulting from the intercalation of sodium ions between the [V4O12]n layers, is demonstrated by single nanowire device. Furthermore, the reversible intercalation reaction mechanism is confirmed by X‐ray diffraction, Raman, X‐ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy analysis. The outstanding performance can be attributed to the stable layered structure and high conductivity of NVO. This work also indicates that layered structural materials show great potential as the cathode of ZIBs, and the indigenous ions can act as pillars to stabilize the layered structure, thereby ensuring an enhanced cycling stability. 相似文献
995.
Efficient Passivation of Hybrid Perovskite Solar Cells Using Organic Dyes with COOH Functional Group 下载免费PDF全文
Xing Li Chun‐Chao Chen Molang Cai Xin Hua Fengxian Xie Xiao Liu Jianli Hua Yi‐Tao Long He Tian Liyuan Han 《Liver Transplantation》2018,8(20)
Organic–inorganic halide perovskites are efficient absorbers for solar cells. Nevertheless, the trap states at the surfaces and grain boundaries are a detrimental factor compromising the device performance. Here, an organic dye (AQ310) is employed as passivator to reduce the trap states of the perovskites and promote better stability. The results demonstrate that the trap states of perovskite are minimized by the presence of AQ310's ?COOH group and the formation of coordination with under‐coordinated Pb2+ ions. The resulting carrier recombination time is prolonged and verified by the photoluminescence and open‐circuit voltage decay measurements. Consequently, the best average power conversion efficiency (PCE) of 19.43% is achieved for the perovskite solar cell (PSC) with AQ310 passivation, as compared with a low average PCE of 17.98% for the PSC without AQ310 passivation. 相似文献
996.
Qing Chen Hong-Mei Wang Wen Zhuang Zhong-Guan Sun Jing Chen Yan Ge Ji-guo Qiu Jian He 《Antonie van Leeuwenhoek》2018,111(11):1977-1984
Strain ZZ-8T, a Gram-negative, aerobic, non-spore-forming, non-motile, yellow-pigmented, rod-shaped bacterium, was isolated from metolachlor-contaminated soil in China. The taxonomic position was investigated using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain ZZ-8T is a member of the genus Flavobacterium and shows high sequence similarity to Flavobacterium humicola UCM-46T (97.2%) and Flavobacterium pedocola UCM-R36T (97.1%), and lower (<?97%) sequence similarity to other known Flavobacterium species. Chemotaxonomic analysis revealed that strain ZZ-8T possessed MK-6 as the major respiratory quinone; and iso-C15:0 (28.5%), summed feature 9 (iso-C17:1 w9c/C16:0 10-methyl, 22.9%), iso-C17:0 3-OH (17.0%), iso-C15:0 3-OH (8.9%), iso-C15:1 G (8.6%) and summed feature 3 (C16:1 w7c/C16:1 w6c, 5.7%) as the predominant fatty acids. The polar lipids of strain ZZ-8T were determined to be lipids, a glycolipid, aminolipids and phosphatidylethanolamine. Strain ZZ-8T showed low DNA–DNA relatedness with F. pedocola UCM-R36T (43.23?±?4.1%) and F. humicola UCM-46T (29.17?±?3.8%). The DNA G+C content was 43.3 mol%. Based on the phylogenetic and phenotypic characteristics, chemotaxonomic data and DNA–DNA hybridization, strain ZZ-8T is considered a novel species of the genus Flavobacterium, for which the name Flavobacterium zaozhuangense sp. nov. (type strain ZZ-8T?=?KCTC 62315 T?=?CCTCC AB 2017243T) is proposed. 相似文献
997.
Methylation‐associated DOK1 and DOK2 down‐regulation: Potential biomarkers for predicting adverse prognosis in acute myeloid leukemia 下载免费PDF全文
998.
999.
Abstract This paper deals with two new species of Phasmatodea from the Xizang Aut. Reg. belonging to Phasmatidae and Heteronemiidae. Their comparisons with close species and figures of characteristics are given. 相似文献
1000.
鲤肠道正常菌群的研究 总被引:24,自引:1,他引:24
本实验用稀释滴种的定量方法,对淡水养殖地中健康鲤肠道内的10种菌群进行了定性、定量分析,并对结果进行统计学处理,得到鲤肠菌群的一些生理值。结果表明鲤肠道中需氧、兼性厌氧优势菌是气单胞菌和酵母菌,厌氧优势菌是拟杆菌。对不同时间、不同温度条件下同一养殖池中鲤肠道菌群的测定结果比较表明:葡萄球菌、假单胞菌差异显著(p<0.05),气单胞菌、大肠杆菌、需氧芽胞杆菌、酵母菌、乳酸杆菌、双歧杆菌、拟杆菌、梭状芽胞杆菌差异不显著(p>0.05),表明该8种菌群在鲤肠道中的菌数处于相对稳定状态,属于肠道正常菌群。 相似文献