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1The zircon SHRIMP chronology and trace elementgeochemistry of the Carboniferous volcanic rocksin western Tianshan Mountains显示文摘The genesis of the Carboniferous volcanic rocks in the Dahalajunshan group, mainly consisting of trachytes and trachy-andesites and distributing widely in western Tianshan Mountains, remains to be controversial. It has been proposed to be relevant to “rift” or “plume”. Detailed pe-trology and geochemical data presented in this paper show that these volcanic rocks represent typical continental arc magmatism. The volcanic rocks are mainly trachy-andesitic, and the magma source is enriched in LILE, Th and Pb, and depleted in HFSE and Ce. Trace element geochemical study suggests that the basalts could be modeled by 7%-11% partial melt of garnet lherzolite. The volcanic rocks in the Dahala-junshan group are neither the products of “rift” nor so-called “plume” but represent the continental island arc of the Pa-leo-Southern Tianshan Ocean. The mantle wedge had been modified by the melt generating in subduction zone during a long evolution history of this island arc. The continental crust materials (i.e. mainly sediment on ocean floor) had been added into island arc through melt in subduction zone. Volcanic rocks occurring in different regions might represent magma eruption in different time. The zircon SHRIMP dat-ing indicates that the ages of the basalt varies between 334.0 Ma and 394.9 Ma. The 13 analyses give an average age of 353.7 ±4.5 Ma (MSWD = 1.7). The apparent ages of zircons in trachy-andesite vary between 293.0 Ma and 465.4 Ma. All analyses fall on the U-Pb concordant line and are divided into two groups. 8 analyses produce an average age of 312.8±4.2 Ma (MSWD = 1.7), which represents the crystal-lizing age of zircon rims in trachy-andesite. The acquired two ages (i.e. 354 and 313 Ma) belong to the Early Carboniferous and Late Carboniferous epochs, respectively. Thus, the Da-halajunshan group would be separated into several groups with the accumulation of high-quality age dating and data of trace element and isotopic geochemistry, in our opinion.ZHU Yongfeng ZHANG Lifei GU Libing GUO Xuan ZHOU Jing 2005Chinese Science Bulletin2005,50,19:188
2Evolution of the novel coronavirus from the ongoing Wuhan outbreak and modeling of its spike protein for risk of human transmission显示文摘Dear Editor,The occurrence of concentrated pneumonia cases in Wuhan city,Hubei province of China was first reported on December 30,2019 by the Wuhan Municipal Health Commission(WHO,2020).The pneumonia cases were found to be linked to a large seafood and animal market in Wuhan,and measures for sanitation and disinfection were taken swiftly by the local government agency.The Centers for Disease Control and Prevention(CDC)and Chinese health authorities later determined and announced that a novel coronavirus(CoV),denoted as 2019-nCoV,had caused the pneumonia outbreak in Wuhan city(CDC,2020).Scientists from multiple groups had obtained the virus samples from hospitalized patients(Normile,2020).The isolated viruses were morphologically identical when observed under electron microscopy.Xintian Xu Ping Chen Jingfang Wang Jiannan Feng Hui Zhou Xuan Li Wu Zhong Pei Hao 2020Science China(Life Sciences)2020,63,3:737
3Anisotropic coding metamaterials and their powerful manipulation of differently polarized terahertz waves显示文摘Metamaterials based on effective media can be used to produce a number of unusual physical properties(for example,negative refraction and invisibility cloaking)because they can be tailored with effective medium parameters that do not occur in nature.Recently,the use of coding metamaterials has been suggested for the control of electromagnetic waves through the design of coding sequences using digital elements‘0’and‘1,'which possess opposite phase responses.Here we propose the concept of an anisotropic coding metamaterial in which the coding behaviors in different directions are dependent on the polarization status of the electromagnetic waves.We experimentally demonstrate an ultrathin and flexible polarization-controlled anisotropic coding metasurface that functions in the terahertz regime using specially designed coding elements.By encoding the elements with elaborately designed coding sequences(both 1-bit and 2-bit sequences),the x-and y-polarized waves can be anomalously reflected or independently diffused in three dimensions.The simulated far-field scattering patterns and near-field distributions are presented to illustrate the dual-functional performance of the encoded metasurface,and the results are consistent with the measured results.We further demonstrate the ability of the anisotropic coding metasurfaces to generate a beam splitter and realize simultaneous anomalous reflections and polarization conversions,thus providing powerful control of differently polarized electromagnetic waves.The proposed method enables versatile beam behaviors under orthogonal polarizations using a single metasurface and has the potential for use in the development of interesting terahertz devices.Shuo Liu Tie Jun Cui Quan Xu Di Bao Liangliang Du Xiang Wan Wen Xuan Tang Chunmei Ouyang Xiao Yang Zhou Hao Yuan Hui Feng Ma Wei Xiang Jiang Jiaguang Han Weili Zhang Qiang Cheng 2016Light(Science & Applications)2016,5,1:36
4Improved survival of porcine acute liver failure by a bioartificial liver device implanted with induced human functional hepatocytes显示文摘Xiao-Lei Shi Yimeng Gao YupengYan HuchengMa Lulu Sun Pengyu Huang Xuan Ni Ludi Zhang Xin Zhao Haozhen Ren Dan Hu Yan Zhou Feng Tian Yuan Ji Xin Cheng Guoyu Pan Yi-Tao Ding LijianHui 2016Cell Research2016,26,2:31
5Homology-mediated end joining-based targeted integration using CRISPR/Cas9显示文摘Yao, Xuan Wang, Xing Hu, Xinde Liu, Zhen Liu, Junlai Zhou, Haibo Shen, Xiaowen Wei, Yu Huang, Zijian Ying, Wenqin Wang, Yan Nie, Yan-Hong Zhang, Chen-Chen Li, Sanlan Cheng, Leping Wang, Qifang Wu, Yan Huang, Pengyu Sun, Qiang Shi, Linyu Yang, Hui 2017Cell Research2017,27,6:28
6Significance of Survivin and PTEN expression in full lymph node-examined gastric cancer显示文摘瞄准:学习在 Survivin 和 PTEN 表示和淋巴节点转移之间的关系,侵略的深度和在中国的胃的癌症病人的预后。方法:胃的癌症组织的标本从 Jianghan 大学的隶属于的医院被收集。所有 140 个病人有完全的考试数据。所有淋巴结被胖空地的方法发现。染色的打断的连续 4 微米节,平淡的苏木精和曙红和免疫组织化学的方法被用来检测淋巴节点转移。胃的癌症织物微数组被执行由免疫在胃的癌症测试 Survivin 和 PTEN (17A ) 的表示组织化学的方法。所有数据多用 chi2 测试,菲希尔的准确测试, Kaplan-Meyer 木头等级方法和考克斯被处理变量分析(社会科学统计套装软体 12.0 软件) 。结果:118 个标本在我们的织物被使用微数组(利用率是 82.4%) 。7580 淋巴结的一个总数被发现。转移在 90 个标本被发现, 1618 淋巴结被检测。Survivin 和 PTEN 表示的积极的率是 52.5%(62/118 ) 并且 76.2%(90/118 ) 分别地。高度积极的关联在 Survivin 和 PTEN 表示之间被发现(chi2 = 4.17, P = 0.04 ) 。Survivin 表示断然与 UICC N 舞台被相关(chi 2 = 8.69, P = 0.03 ) 并且组织学的分类(chi2 = 4.41, P = 0.04 ) 由 chi2 测试。PTEN 表示断然与侵略的深度被相关(P = 0.02 ) 并且组织学的分类(chi2 = 5.47, P = 0.02 ) 。但是 Survivin 和 PTEN 表情没与胃的癌症病人的预后被联系。在淋巴节点转移和预后之间的重要关联被考克斯多表明变量分析(chi2 = 4.85, P = 0.028 ) 。结论:Survivin 断然在胃的癌症与 PTEN 表示被相关并且当 PTEN 表示是先进胃的癌症的一个分子的标记时,是淋巴节点转移的一个分子的标记。UICC N 舞台是在中国的胃的癌症的最重要的预示的因素。Hao Deng Ren-Liang Wu Hong-Yan Zhou Xuan Huang Ying Chen Li-Jiang Liu 2006World Journal of Gastroenterology2006,12,7:26
7Molecular mechanism of hepatitis B virus X protein function in hepatocarcinogenesis显示文摘Many factors are considered to contribute to hepatitis B virus(HBV)-associated hepatocellular carcinoma(HCC),including products of HBV,HBV integration and mutation,and host susceptibility. HBV X protein(HBx) can interfere with several signaling pathways associated with cell proliferation and invasion,and HBx C-terminal truncation has been suggested to impact the development of HCC. This review focuses on the pathological functions of HBx in HBV-induced hepatocarcinogenesis. As a transactivator,HBx can affect regulatory non-coding RNAs(nc RNAs),including micro RNAs and long nc RNAs. HBx is also involved in epigenetic modification and DNA repair. HBx interacts with various signal-transduction pathways,such as the p53,Wnt,and nuclear factor-κB pathways. We conclude that HBx hastens the development of hepatoma.Ming Geng Xuan Xin Li-Quan Bi Lu-Ting Zhou Xiao-Hong Liu 2015World Journal of Gastroenterology2015,21,38:24
8Big data challenge: a data management perspective显示文摘Jinchuan CHEN Yueguo CHEN Xiaoyong DU Cuiping LI Jiaheng LU Suyun ZHAO Xuan ZHOU 2013Frontiers of Computer Science2013,7,2:21
9One-step generation of complete gene knockout mice and monkeys by CRISPR/Cas9-mediated gene editing with multiple sgRNAs显示文摘CRISPR/Cas9 系统是一个有效编辑基因的方法,但是编辑基因的动物的多数显示出 mosaicism,与编辑仅仅在房间的部分发生。这里,我们证明那单个基因或多重基因能被 Cas9 mRNA 和多重邻近的单个指南的 RNA 的 zygotic 注射完全在老鼠和猴子胚胎击倒(spaced 10-200 bp 分开) 指向仅仅一把单个钥匙每基因的 exon。个别地在 Y 染色体上跟随八基因的指向的删除的 F0 老鼠的 Phenotypic 分析在产生猛烈老鼠表明了这条途径的坚韧性。重要地,这条途径在高效率交付完全的基因大美人(Arntl 上的 100% 并且 91% 在 Prrt2 上) 在猴子胚胎。最后,我们能在一个单个步骤产生一只完全的 Prrt2 猛烈猴子,表明在很快建立编辑基因的猴子模型的这条途径的实用性。Erwei Zuo Yi-Jun Cai Kui Li Yu Wei Bang-An Wang Yidi Sun Zhen Liu Jiwei Liu Xinde Hu Wei Wei Xiaona Huo Linyu Shi Cheng Tang Dan Liang Yan Wang Yan-Hong Nie Chen-Chen Zhang Xuan Yao Xing Wang Changyang Zhou Wenqin Ying Qifang Wang Ren-Chao Chen Qi Shen Guo-Liang Xu Jinsong Li Qiang Sun Zhi-Qi Xiong Hui Yang 2017Cell Research2017,27,7:21
10Carbon monoxide-induced adventitious rooting of hypo-cotyl cuttings from mung bean seedling显示文摘In this paper, the regulatory role of ex-ogenous carbon monoxide (CO) during the genera-tion and development of adventitious roots in mung bean (Phaseolus radiatus L. cv. Mingguang) hypo-cotyl cuttings was surveyed. The results indicated that, like nitric oxide (NO), CO donor Hematin in-duced adventitious rooting in dose- and time-de- pendent manners. These responses were also prov- en by the addition of gaseous CO aqueous solution with different concentrations. Additionally, the above CO-mediated effect was differently reversed when CO scavenger hemoglobin (Hb), CO specific syn-thetic inhibitor ZnPPIX, the auxin transport inhibitor NPA and nitric oxide synthase (NOS) inhibitor L-NAME were added with Hematin, respectively. Furthermore, after being treated with CO for 36 h, NO fluorescence was significantly enhanced and mainly distributed in the zone of vascular bundles whereas the specific NO scavenger cPTIO significantly inhib-ited NO fluorescence induced by CO, indicating that CO induces adventitious rooting of hypocotyl cuttings from mung bean seedling probably mediated by NO/NOS pathway.XU Ji XUAN Wei HUANG Benkai ZHOU Yehua LING Tengfang XU Sheng SHEN Wenbiao 2006Chinese Science Bulletin2006,51,6:16
11Evaluation of hyperreflective foci as a prognostic factor of visual outcome in retinal vein occlusion显示文摘AIM:To evaluate the potential role of hyperreflective foci(HF) as a prognostic indicator of visual outcome in patients with macular edema(ME) due to retinal vein occlusion(RVO).METHODS:We retrospectively reviewed 50 eyes of 50 patients with ME due to ischemic central retinal vein occlusion(CRVO),non-ischemic CRVO and branch retinal vein occlusion(BRVO) who were treated with anti-vascular endothelial growth factor(anti-VEGF) at Beijing Tongren Eye Center from January 2013 to July 2016.All patients underwent best-corrected visual acuity(BCVA),spectral domain optical coherence tomography(SD-OCT) at baseline and follow-up.Such factors were evaluated and compared among three groups as baseline and final BCVA,central retinal thickness(CRT),external limiting membrane(ELM) status and the numbers of HF in different position.Multiple linear regression analysis was employed to analyze the relationship between baseline HF and final BCVA.Changes of HF before and after treatment were evaluated too.RESULTS:Among three groups,HF could be located in each retinal layers,as well as in vitreous cavity.The mean HF in outer retinal layer(ORL) at baseline was 5.29±8.48 in ischemic CRVO with intact ELM,1.93±2.76 in non-ischemic CRVO,and 1.75±2.05 in BRVO.With disrupted ELM,the mean HF in ORL increased.There was statistically difference of HF in ORL between intact and disrupted ELM.The numbers of HF in ORL were associated with poor visual outcome among three groups.However,HF in inner retinal layer(IRL) and vitreous cavity were not associated with poor visual outcome.Meanwhile,the baseline HF in ORL and vitreous cavity reduced significantly in nonischemic CRVO and BRVO after anti-VEGF treatment.CONCLUSION:The numbers of HF in ORL are prognostic factors associated with the final BCVA in patients with ME due to RVO after anti-VEGF treatment.Bin Mo Hai-Ying Zhou Xuan Jiao Feng Zhang 2017International Journal of Ophthalmology(English edition)2017,10,4:15
12High levels of serum interleukin-6 increase mortality of hepatitis B virus-associated acute-on-chronic liver failure显示文摘BACKGROUND Patients with hepatitis B virus-associated acute-on-chronic liver failure(HBVACLF)present a complex and poor prognosis.Systemic inflammation plays an important role in its pathogenesis,and interleukin-6(IL-6)as a pro-inflammatory cytokine is related with severe liver impairment and also plays a role in promoting liver regeneration.Whether serum IL-6 influences HBV-ACLF prognosis has not been studied.AIM To determine the impact of serum IL-6 on outcome of patients with HBV-ACLF.METHODS We performed a retrospective study of 412 HBV-ACLF patients.The findings were analyzed with regard to mortality and the serum IL-6 level at baseline,as well as dynamic changes of serum IL-6 within 4 wk.RESULTS The serum IL-6 level was associated with mortality.Within 4 wk,deceased patients had significantly higher levels of IL-6 at baseline than surviving patients[17.9(7.3-57.6)vs 10.4(4.7-22.3),P=0.011].Patients with high IL-6 levels(>11.8 pg/mL)had a higher mortality within 4 wk than those with low IL-6 levels(≤11.8 pg/mL)(24.2%vs 13.2%,P=0.004).The odds ratios calculated using univariate and multivariate logistic regression were 2.10(95%confidence interval[CI]:1.26-3.51,P=0.005)and 2.11(95%CI:1.15-3.90,P=0.017),respectively.The mortality between weeks 5 and 8 in patients with high IL-6 levels at 4 wk was 15.0%,which was significantly higher than the 6.6%mortality rate in patients with low IL-6 levels at 4 wk(hazard ratio=2.39,95%CI:1.05-5.41,P=0.037).The mortality was 5.0%in patients with high IL-6 levels at baseline and low IL-6 levels at 4 wk,7.5%in patients with low IL-6 levels both at baseline and at 4 wk,11.5%in patients with low IL-6 levels at baseline and high IL-6 levels at 4 wk,and 16.7%in patients with high IL-6 levels both at baseline and at 4 wk.The increasing trend of the mortality rate with the dynamic changes of IL-6 was significant(P for trend=0.023).CONCLUSION A high level of serum IL-6 is an independent risk factor for mortality in patients with HBV-ACLF.Furthermore,a sustained high level or dynamic elevated level of serum IL-6 indicates a higher mortality.Chao Zhou Ning Zhang Ting-Ting He Yao Wang Li-Fu Wang Yong-Qiang Sun Jing Jing Jing-Jing Zhang Shuang-Nan Fu Xuan Wang Xiao-Xiao Liang Xin Li Man Gong Jun Li 2020World Journal of Gastroenterology2020,26,30:15
13Zscan4 promotes genomic stability during reprogramming and dramatically improves the quality of iPS cells as demonstrated by tetraploid complementation显示文摘用 Yamanaka 因素产生的导致的 pluripotent 茎(iPS ) 细胞在自体同源的细胞治疗为使用有大潜力。然而, genomic 畸形充分在人的 iPS 房间,和房间不是的大多数老鼠 iPS 存在 pluripotent 由 tetraploid 互补试金评估了 TCA ) ;这很可能与 DNA 损坏反应(DDR ) 被联系在 Yamanaka 因素导致的早 reprogramming 发生了。相反,原子转移忠实地装改编体的房间进胚胎的茎(ES ) 满足 TCA 的房间。我们因此假设了涉及导致卵母细胞的 reprogramming 的因素可以在 reprogramming 期间稳定体的染色体,并且改进结果的 iPS 房间的质量。测试这个假设,我们在 iPS 期间为能减少的因素屏蔽了 DDR 信号房间正式就职。我们决定了那 Zscan4,在有 Yamanaka 因素的联合,不是仅仅显著地减少了 DDR 而且显著地支持了 iPS 房间产生的效率。Zscan4 的包括稳定了 genomic DNA,导致 p53 downregulation。而且, Zscan4 也提高了象通过 telomere 感染以后的 3 天一样早变长的 telomere 基于再结合的机制。作为结果,与 Zscan4 的增加产生的 iPS 房间比古典 iPS 房间展出了更长的 telomeres。惊人地,超过 50% iPS 房间线(11/19 ) 经由这生产了 “ Zscan4 protocol”产生了由 TCA 决定了的实时熊的 all-iPS 房间老鼠,与为用古典 Yamanaka 因素生产的线的 1/12 相比。我们的调查结果提供在 reprogramming 期间维持 genomic 稳定性支持的第一示范高质量的 iPS 房间的产生。Jing Jiang Wenjian Lv Xiaoying Ye Lingbo Wang Man Zhang Hui Yang Maja Okuka Chikai Zhou Xuan Zhang Lin Liu Jinsong Li 2013Cell Research2013,23,1:14
14Xiaotan Sanjie decoction attenuates tumor angiogenesis by manipulating Notch-1-regulated proliferation of gastric cancer stem-like cells显示文摘AIM: To determine the underlying mechanisms of action and influence of Xiaotan Sanjie(XTSJ) decoction on gastric cancer stem-like cells(GCSCs). METHODS: The gastric cancer cell line MKN-45 line was selected and sorted by FACS using the cancer stem cell marker CD44; the stemness of these cells was checked in our previous study. In an in vitro study, the expression of Notch-1, Hes1, Vascular endothelial growth factor(VEGF), and Ki-67 in both CD44-positive gastric cancer stem-like cells(GCSCs) and CD44-negative cells was measured by Western blot. The effect of XTSJ serum on cell viability and on the above markers was measured by MTT assay and Western blot, respectively. In an in vivo study, the ability to induce angiogenesis and maintenance of GCSCs in CD44-positive-MKN-45- and CD44-negative-engrafted mice were detected by immunohistochemical staining using markers for CD34 and CD44, respectively. The role of XTSJ decoction in regulating the expression of Notch-1, Hes1, VEGF and Ki-67 was measured by Western blot and real-time polymerase chain reaction.RESULTS: CD44+ GCSCs showed more cell proliferation and VEGF secretion than CD44-negative cells in vitro, which were accompanied by the high expression of Notch-1 and Hes1 and positively associated with tumor growth(GCSCs vs CD44-negative cells, 2.72 ± 0.25 vs 1.46 ± 0.16, P < 0.05) and microvessel density(MVD)(GCSCs vs CD44-negative cells, 8.15 ± 0.42 vs 3.83 ± 0.49, P < 0.001) in vivo. XTSJ decoction inhibited the viability of both cell types in a dose-dependent manner in vitro. Specifically, a significant difference in the medium-(82.87% ± 6.53%) and high-dose XTSJ groups(77.43% ± 7.34%) was detected at 24 h in the CD44+ GCSCs group compared with the saline group(95.42% ± 5.76%) and the low-dose XTSJ group(90.74% ± 6.57%)(P < 0.05). However, the efficacy of XTSJ decoction was reduced in the CD44- groups; significant differences were only detected in the high-dose XTSJ group at 48 h(78.57% ± 6.94%) and 72 h(72.12% ± 7.68%) when compared with the other CD44- groups(P < 0.05). Notably, these differences were highly consistent with the Notch-1, Hes1, VEGF and Ki-67 expression in these cells. Similarly, in vivo, XTSJ decoction inhibited tumor growth in a dose-dependent manner. A significant difference was observed in the medium(1.76 ± 0.15) and high-dose XTSJ(1.33 ± 0.081) groups compared with the GCSCs control group(2.72 ± 0.25) and the low-dose XTSJ group(2.51 ± 0.25)(P < 0.05). We also detected a remarkable decrease of MVD in the medium-(7.10 ± 0.60) and high-dose XTSJ(5.99 ± 0.47) groups compared with the GCSC control group(8.15 ± 0.42) and the low-dose XTSJ group(8.14 ± 0.46)(P < 0.05). Additionally, CD44 expression was decreased in these groups [medium-(4.43 ± 0.45) and high-dose XTSJ groups(3.56 ± 0.31) vs the GCSC control(5.96 ± 0.46) and low dose XTSJ groups(5.91 ± 0.38)](P < 0.05). The significant differences in Notch-1, Hes1, VEGF and Ki-67 expression highly mirrored the results of XTSJ decoction in inhibiting tumor growth, MVD and CD44 expression.CONCLUSION: Notch-1 may play an important role in regulating the proliferation of GCSCs; XTSJ decoction could attenuate tumor angiogenesis, at least partially, by inhibiting Notch-1.Bing Yan Long Liu Ying Zhao Li-Juan Xiu Da-Zhi Sun Xuan Liu Ye Lu Jun Shi Yin-Cheng Zhang Yong-Jin Li Xiao-Wei Wang Yu-Qi Zhou Shou-Han Feng Can Lv Pin-Kang Wei Zhi-Feng Qin 2014World Journal of Gastroenterology2014,20,36:14
15Impact of anthropogenic activities on the sediment microbial communities of Baiyangdian shallow lake显示文摘Microorganisms are recognized as sensors of external disturbance in freshwater ecosystems.In this study,sediment samples from regions with strong human activity interference(four sites),moderate human activity interference(five sites)and minor human activity interference(five sites)in Baiyangdian Lake were collected;and their physiological and chemical properties and heavy metals contents were analyzed.The structures of bacterial and fungal communities were tested using 16S ribosomal Ribonucleic Acid(rRNA)and Internal Transcribed Spacer 2(ITS2)high-throughput sequencing technologies.The results indicated that Proteobacteria was the most abundant bacterial phylum.Ascomycota,Basidiomycota and Ciliophora were the dominant phyla of fungi.Obvious differences of microbial genera among the three regions were observed,especially fungal genera.With intensified disturbance by human activities,the Simpson and Shannon indices of bacteria significantly decreased.The fungal communities were clustered into three groups in accordance with the different human disturbance levels.The bacterial communities of sediment samples under moderate and minor human disturbance appeared similar,but different from those under strong human disturbance.Redundancy analysis indicated that zinc,total phosphorus,copper,and lead were the dominant factors that influenced the bacterial community.Nitrifiers and sulfate-reducing bacteria were influenced by pH,nitrate(NO3 ),and total nitrogen.The fungal community was significantly affected by total phosphorus.This study reveals that sediment microbial community structures among different regions of a shallow lake are mainly impacted by human activities.Wenjun Wang Yujun Yi Yufeng Yang Yang Zhou Shanghong Zhang Xuan Wang Zhifeng Yang 2020International Journal of Sediment Research2020,35,2:14
16Arctigenin enhances swimming endurance of sedentary rats partially by regulation of antioxidant pathways显示文摘Ruo-ming WU Yan-yan SUN Ting-ting ZHOU Zhi-yuan ZHU Jing-jing ZHUANG Xuan TANG Jing CHEN Li-hong HU Xu SHEN 2014Acta Pharmacologica Sinica2014,35,10:13
17X-ray image characteristics and related measurements in the ankles of 118 adult patients with Kashin-Beck disease显示文摘Zeng Yi Zhou Zongke Shen Bin Yang Jing Kang Pengde Zhou Xuan Zou Ling Pei Fuxing 2014Chinese Medical Journal2014,,13:13
18Synergistic effect between Sn and K promoters on supported platinum catalyst for isobutane dehydrogenation显示文摘Catalytic dehydrogenation of isobutane has recently received considerable attention because of the increasing demand for isobutene.In this study,the synergistic effect between Sn and K on PtSnK/γ-Al2O3 catalysts has been investigated by changing the content of Sn.It was found that with the presence of potassium,suitable addition of Sn could not only increase the metal dispersion,but also reduce the catalyst acidity.In these cases,the synergistic effect could also strengthen the interactions between the metal and support,which resulted in an increase in both catalytic activity and stability.In our experiments,Pt-0.6SnK/Al catalyst exhibited the lowest deactivation rate (12.4%) and showed a selectivity to isobutene higher than 94% at the isobutane conversion of about 45.3% after running the reaction for 6 h.However,with the excessive loading of Sn,surface property of active sites and the interactions between metal and support were changed.As a result,the initial optimal ratio between the metallic function and acid function would be destroyed,which was disadvantageous to the reaction.Yiwei Zhang Yuming Zhou Lihui Wan Mengwei Xue Yongzheng Duan Xuan Liu 2011Journal of Natural Gas Chemistry2011,20,6:12
19Group decision-making method based on entropy and experts cluster analysis显示文摘According to the aggregation method of experts' evaluation information in group decision-making,the existing methods of determining experts' weights based on cluster analysis take into account the expert's preferences and the consistency of expert's collating vectors,but they lack of the measure of information similarity.So it may occur that although the collating vector is similar to the group consensus,information uncertainty is great of a certain expert.However,it is clustered to a larger group and given a high weight.For this,a new aggregation method based on entropy and cluster analysis in group decision-making process is provided,in which the collating vectors are classified with information similarity coefficient,and the experts' weights are determined according to the result of classification,the entropy of collating vectors and the judgment matrix consistency.Finally,a numerical example shows that the method is feasible and effective.Xuan Zhou Fengming Zhang Xiaobin Hui Kewu Li 2011Journal of Systems Engineering and Electronics2011,22,3:12
20Experiment on Leader Propagation Characteristics of Air Gaps in UHVDC Transmission Towers Under Positive Switching Impulse Voltages显示文摘Rapid developments in EHV/UHV transmission systems require a deeper understanding of the mechanism of long air gap discharge.Leader propagation is one of the main processes in long gap breakdown.In this paper,the leader propagation characteristics of real size±800 kV UHVDC transmission tower gaps under positive switching impulse voltages(185/2290μs)are investigated.An integrated observation platform consisting of an impulse voltage divider,a coaxial shunt,a high-speed video camera,and a set of integrated optical electric field sensors(IOES),is established.The waveforms of impulse voltage,discharge current,electric field variation at specific positions,and time-resolved photographs of discharge morphology are recorded.Axial leader velocity and the relationship between leader advancements and injected charge are obtained.The typical value of leader stable propagation velocity is 1.7–2.2 cm/μs,which varies slightly with the gap length and applied voltage amplitude.The leader velocity in the re-illumination process is much higher,and is seen as varying from 5 cm/μs to 30 cm/μs,with an average value around 10 cm/μs.The charge in leader channel per unit length is 20–40μC/m,which illustrates a near-direct proportion relationship between discharge current and leader velocity.The observed parameters are important for further simulation of the tower gap breakdown processes.Xuan Zhou She Chen Hai Wang Rong Zeng Chijie Zhuang Junjie Yu Yujian Ding 2015CSEE Journal of Power and Energy Systems2015,1,3:12
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