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172篇 您的检索式:作者名="Peng Gan"
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1A complete sequence and comparative analysis of a SARS-associated virus(Isolate BJ01)显示文摘The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs. We report the complete genome sequence and comparative analysis of an isolate (BJ01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 2 ORFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS- associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymous mutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to beinvolved in the immunoreactions between the virus and its host. Two amino acid changes have been detected in the Mprotein, which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides noevidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of otherpossible SARS-related pathogen(s).QIN E'de ZHU Qingyu YU Man FAN Baochang CHANG Guohui SI Bingyin YANG Bao PENG Wenming JIANG Tao LIU Bohua DENG Yongqiang LIU Hong ZHANG Yu WANG Cui LI Yuquan GAN Yonghua LI Xiaoyu L Fushuang TAN Gang CAO Wuchun, YANG Ruifu Institute of Microbiology and Epidemiology, Chinese Academy of Military Medical Sciences, Beijing 100071, China WANG Jian, LI Wei, XU Zuyuan, LI Yan, WU Qingfa, LIN Wei, CHEN Weijun, TANG Lin, DENG Yajun, HAN Yujun, LI Changfeng, LEI Meng, LI Guoqing, LI Wenjie, L Hong, SHI Jianping, TONG Zongzhong, ZHANG Feng, LI Songgang, LIU Bin, LIU Siqi, DONG Wei, WANG Jun, Gane K-S Wong, YU Jun & YANG Huanming* Beijing Genomics Institute, Chinese Academy of Sciences, Beijing 101300 National Center for Genome Information, Beijing 101300, China 2003Chinese Science Bulletin2003,48,10:121
2GPS-constrained inversion of present-day slip rates along major faults of the Sichuan-Yunnan region, China显示文摘A linked-fault-element model is employed to invert for contemporary slip rates along major active faults in the Sichuan-Yunnan region (96°-108°E, 21°-35°N) using the least squares method. The model is based on known fault geometry, and constrained by a GPS-derived horizontal velocity field. Our results support a model attributing the eastward extrusion of the Tibetan Plateau driven mainly by the north-northeastward indentation of the Indian plate into Tibet and the gravitational collapse of the plateau. Resisted by a relatively stable south China block, materials of the Sichuan-Yunnan region rotate clockwise around the eastern Himalayan tectonic syntaxis. During the process the Garzê-Yushu, Xianshuihe, Anninghe, Zemuhe, Daliangshan, and Xiaojiang faults, the southwest extension of the Xiaojiang fault, and the Daluo-Jinghong and Mae Chan faults constitute the northeast and east boundaries of the eastward extrusion, with their left slip rates being 0.3-14.7, 8.9-17.1, 5.1 ± 2.5, 2.8 ± 2.3, 7.1 ± 2.1, 9.4 ± 1.2, 10.1 ± 2.0, 7.3 ± 2.6, and 4.9 ± 3.0 mm/a respectively. The southwestern boundary consists of a widely distributed dextral transpressional zone other than a single fault. Right slip rates of 4.2 ± 1.3, 4.3 ± 1.1, and 8.5 ± 1.7 mm/a are detected across the Nanhua-Chuxiong-Jianshui, Wuliangshan, and Longling-Lancang faults. Crustal deformation across the Longmenshan fault is weak, with short-ening rates of 1.4 ± 1.0 and 1.6 ± 1.3 mm/a across the Baoxing-Beichuan and Beichuan-Qingchuan segments. Northwest of the Longmenshan fault lies an active deformation zone (the Longriba fault) with 5.1±1.2 mm/a right slip across. Relatively large slip rates are detected across a few faults within the Sichuan-Yunnan block: 4.4±1.3 mm/a left slip and 2.7±1.1 mm/a shortening across the Litang fault, and 2.7±2.3 mm/a right-lateral shearing and 6.7±2.3 mm/a shortening across the Yunongxi fault and its surrounding regions. In conclusion, we find that the Sichuan-Yunnan region is divided into more than a dozen active micro-blocks by a large number of faults with relatively slow slip rates. The eastward extrusion of the Tibetan Plateau is absorbed and adjusted in the region mainly by these faults, other than a small number of large strike-slip faults with fast slip rates.WANG YanZhao WANG EnNing SHEN ZhengKang WANG Min GAN WeiJun QIAO XueJun MENG GuoJie LI TieMing TAO Wei YANG YongLin CHENG Jia LI Peng 2008Science China Earth Sciences2008,51,9:65
3Effects of mixture ratio on anaerobic co-digestion with fruit and vegetable waste and food waste of China显示文摘The biochemical methane potentials for typical fruit and vegetable waste (FVW) and food waste (FW) from a northern China city were investigated,which were 0.30,0.56 m 3 CH 4/kgVS (volatile solids) with biodegradabilities of 59.3% and 83.6%,respectively.Individual anaerobic digestion testes of FVW and FW were conducted at the organic loading rate (OLR) of 3 kg VS/(m 3 ·day) using a lab-scale continuous stirred-tank reactor at 35℃.FVW could be digested stably with the biogas production rate of 2.17 m 3/(m 3 ·day) and methane production yield of 0.42 m 3 CH 4/kg VS.However,anaerobic digestion process for FW was failed due to acids accumulation.The effects of FVW:FW ratio on co-digestion stability and performance were further investigated at the same OLR.At FVW and FW mixing ratios of 2:1 and 1:1,the performance and operation of the digester were maintained stable,with no accumulation of volatile fatty acids (VFA) and ammonia.Changing the feed to a higher FW content in a ratio of FVW to FW 1:2,resulted in an increase in VFAs concentration to 1100-1200mg/L,and the methanogenesis was slightly inhibited.At the optimum mixture ratio 1:1 for co-digestion of FVW with FW,the methane production yield was 0.49 m 3 CH 4/kg VS,and the volatile solids and soluble chemical oxygen demand (sCOD) removal efficiencies were 74.9% and 96.1%,respectively.Jia Lin Jiane Zuo Lili Gan Peng Li Fenglin Liu Kaijun Wang Lei Chen Hainan Gan 2011Journal of Environmental Sciences2011,23,8:36
4Effects of Grazing Intensity on Soil Water Regime and Flux in Inner Mongolia Grassland,China显示文摘In the past few decades,the increase in grazing intensity has led to soil degradation and desertification in Inner Mongolia grassland,China,due to population growth and shift in the socio-economic system.Two sites with different grazing intensities,continuous grazing site(CG) with 1.2 sheep ha 1 year 1 and heavy grazing site(HG) with 2.0 sheep ha 1 year 1,were investigated at the Inner Mongolia Grassland Ecosystem Research Station(43 37 50 N,116 42 18 E) situated in the northern China to i) characterize the temporal distribution of soil water content along soil profile;and ii) quantify the water fluxes as affected by grazing intensity.Soil water content was monitored by time domain reflectometry(TDR) probes.Soil water retention curves were determined by pressure membrane extractor,furthermore processed by RETC(RETention Curve) software.Soil matric potential,plant available water and water flux were calculated using these data.Both sites showed an identical seasonal soil water dynamics within four defined hydraulic periods:1) wetting transition coincided with a dramatic water increase due to snow and frozen soil thawing from March to April;2) wet summer,rainfall in accordance with plant growth from May to September;3) drying transition,a decrease of soil water from October to November due to rainfall limit;and 4) dry winter,freezing from December to next February.Heavy grazing largely reduced soil water content by 43%-48% and plant available water by 46%-61% as compared to the CG site.During growing season net water flux was nearly similar between HG(242 mm) and CG(223 mm) sites between 5 and 20 cm depths.However,between 20 and 40 cm depths,the upward flux was more pronounced at HG site than at CG site,indicating that water was depleted by root uptake at HG site but stored at CG site.In semi-arid grassland ecosystem,grazing intensity can affect soil water regime and flux,particularly in the growing season.GAN Lei PENG Xin-Hua S.PETH R.HORN 2012Pedosphere2012,22,2:22
5Natural history of covert hepatic encephalopathy: An observational study of 366 cirrhotic patients显示文摘AIM To explore the natural history of covert hepatic encephalopathy(CHE) in absence of medication intervention.METHODS Consecutive outpatient cirrhotic patients in a Chinese tertiary care hospital were enrolled and evaluated for CHE diagnosis. They were followed up for a mean of 11.2 ± 1.3 mo. Time to the first cirrhosis-related complications requiring hospitalization, including overt HE(OHE), resolution of CHE and death/transplantation, were compared between CHE and no-CHE patients. Predictors for complication(s) and death/transplantation were also analyzed.RESULTS A total of 366 patients(age: 47.2 ± 8.6 years, male: 73.0%) were enrolled. CHE was identified in 131 patients(35.8%). CHE patients had higher rates of death and incidence of complications requiring hospitalization, including OHE, compared to unimpaired patients. Moreover, 17.6% of CHE patients developed OHE, 42.0% suffered persistent CHE, and 19.8% of CHE spontaneously resolved. In CHE patients, serum albumin < 30 g/L(HR = 5.22, P = 0.03) was the sole predictor for developing OHE, and blood creatinine > 133 μmol/L(HR = 4.75, P = 0.036) predicted mortality. Child-Pugh B/C(HR = 0.084, P < 0.001) and OHE history(HR = 0.15, P = 0.014) were predictors of spontaneous resolution of CHE.CONCLUSION CHE exacerbates, persists or resolves without medication intervention in clinically stable cirrhosis. Triage of patients based on these predictors will allow for more cost-effect management of CHE.An-Jiang Wang A-Ping Peng Bi-Min Li Na Gan Li Pei Xue-Lian Zheng Jun-Bo Hong Hai-Ying Xiao Jia-Wei Zhong Xuan Zhu 2017World Journal of Gastroenterology2017,23,34:22
6Genotypic Characterization of Methicillin-resistant Staphylococcus aureus Isolated from Pigs and Retail Foods in China显示文摘Objective To investigate the genotypic diversity of Methicillin-resistant Staphylococcus aureus(MRSA) isolated from pigs and retail foods from different geographical areas in China and further to study the routes and rates of transmission of this pathogen from animals to food. Methods Seventy-one MRSA isolates were obtained from pigs and retail foods and then characterized by multi-locus sequencing typing(MLST), spa typing, multiple-locus variable number of tandem repeat analysis(MLVA), pulsed-field gel electrophoresis(PFGE), and antimicrobial susceptibility testing. Results All isolated MRSA exhibited multi-drug resistance(MDR). Greater diversity was found in food-associated MRSA(7 STs, 8 spa types, and 10 MLVA patterns) compared to pig-associated MRSA(3 STs, 1 spa type, and 6 MLVA patterns). PFGE patterns were more diverse for pig-associated MRSA than those of food-associated isolates(40 vs. 11 pulse types). Among the pig-associated isolates, CC9-ST9-t899-MC2236 was the most prevalent clone(96.4%), and CC9-ST9-t437-MC621(20.0%) was the predominant clone among the food-associated isolates. The CC9-ST9 isolates showed significantly higher antimicrobial resistance than other clones. Interestingly, CC398-ST398-t034 clone was identified from both pig-and food-associated isolates. Of note, some community-and hospital-associated MRSA strains(t030, t172, t1244, and t4549) were also identified as food-associated isolates. Conclusion CC9-ST9-t899-MC2236-MDR was the most predominant clone in pigs, but significant genetic diversity was observed in food-associated MRSA. Our results demonstrate the great need for improved surveillance of MRSA in livestock and food and effective prevention strategies to limit MDR-MRSA infections in China.WANG Wei LIU Feng ZULQARNAIN Baloch ZHANG Cun Shan MA Ke PENG Zi Xin YAN Shao Fei HU Yu Jie GAN Xin DONG Yin Ping BAI Yao LI Feng Qin YAN Xiao Mei MA Ai Guo XU Jin 2017Biomedical and Environmental Sciences2017,30,8:13
7Fate of Urea Nitrogen Applied to Rape Grown on a Red Soil and Efficiency of Urea in Raising Rape Yield显示文摘FateofUreaNitrogenAppliedtoRapeGrownonaRedSoilandEfficiencyofUreainRaisingRapeYieldCAIGUI-XIN;PENGGUANG-HAO;WUYI-WEI;MAMAO-TO...CAI GUI-XIN PENG GUANG-HAO WU YI-WEI MA MAO-TONG GAN SHOU-WEN and MEN CI-FU(Institute of Soil Science, Academia Sinica, Nanjing 210008 ( China))(Zhejiang Academy of Agricultural Sciences, Hangzhou 310021 ( China))(Chinese Academy of Agricultual Scie 1995Pedosphere1995,5,2:13
8Molecular organic geochemical peculiarities of lacustrine core sediments in Fildes Peninsula, King George Island, Antarctica显示文摘The peculiarities of lipids in lacustrine core sediments from Fildes Peninsula, King George Island, Antarctica, are reported. The origin of high-molecular-weight n-alkanes, alkenes, fatty acids, alcohols is supposed to be related to the abundant moss occurring in the sediments. Abundant iso- and ante/so-fatty acids that occur in the sediments indicate a relatively strong bacterial activity in non-ice-cover zone than in other regions in Antarctica. The C18:2 unsaturated fatty acids mainly originate from autochthonous algae in the sediment pool, and the C18:2/C18:0 ratios in the profile are controlled more by paleotemperatures than source assemblies. Long-chain alkenones were identified in freshwater lacustrine sediment in Antarctica for the first time, of which Prymnesiophyceae is assumed to be the source organism. High relative abundance of C37:4 homologue in long-chain alkenone well correlates to the severely cold climate in Antarctica.ZHANG Gan SHENG Guoying PENG Ping’an ZHENG Honghan 2000Chinese Science Bulletin2000,45,S1:13
9Polydatin ameliorates Staphylococcus aureus- induced mastitis in mice via inhibiting TLR2- mediated activation of the p38 MAPK/NF-κB pathway显示文摘最近的研究显示出从蓼 cuspidatum Sieb 的根提取的那 Polydatin (PD ) ,广泛地使用的繁体中文补救,在几个试验性的模型拥有反煽动性的活动。在这研究,我们在老鼠在葡萄球菌导致 aureus 的乳腺炎上调查了 PD 的反煽动性的效果并且阐明潜在的机制。在有 S 导致aureus 的乳腺炎的老鼠, PD 的管理( 15 , 30 , 45 mg/kg , ip )或 dexamethasone ( Dex , 5 mg/kg , ip )显著地压制了煽动性的房间的渗入,改善乳房的结构的损坏,并且禁止了 myeloperoxidase 的活动, neutrophils 累积的 biomarker 。而且, PD 处理 dose-dependently 减少了在乳腺纸巾的 TNF- , IL-1, IL-6 和 IL-8 的层次。PD 治疗 dose-dependently 也减少了象在乳腺纸巾的 TAK1, MKK3/6, p38 MAPK, IB-B 和 NF-B 的 phosphorylation 一样的 TLR2, MyD88, IRAK1, IRAK4 和 TRAF6 的表示。在乳房的上皮的房间(mMECs ) 在 vitro 由 S aureus 感染了的老鼠,有 PD 的预告的处理 dose-dependently 压制了 upregulated 支持 inflammatory cytokines 和发信号的蛋白质,和 NF-B p65 和 AP-1 的原子 translocation。抵销 TLR2 抗体在 mMECs 在 MyD88, p-p38 和 p-p65 层次的 S 导致 aureus 的 upregulation 上在它的抑制模仿了 PD。PD (50, 100 g/mL ) 在 mMECs 的 vitro,也不生存能力影响了 S aureus 的既不生长。在结论, PD 不对 S aureus 展出抗菌剂活动,它在老鼠 S 导致 aureus 的乳腺炎的治疗学的效果经由禁止 p38 的调停 TLR2 的激活取决于它的能力到下面调整支持 inflammatory cytokine 层次 MAPK/NF-B 发信号小径。Kang-feng JIANG Gan ZHAO Gan-zhen DENG Hai-chong WU Nan-nan YIN Xiu-ying CHEN Chang-wei QIU Xiu-li PENG 2017Acta Pharmacologica Sinica2017,38,2:13
10Nidus vespae protein inhibiting proliferation of HepG2 hepatoma cells through extracellular signal-regulated kinase signaling pathways and inducing G1 cell cycle arrest显示文摘蛋白质说出 NVP (1 ) 从巢 vespae 被孤立。T 他现在的学习的目的是阐明 NVP (1 ) 是否并且怎么调制 HepG2 房间的增长。在 6.6 μg/ml 的集中的 NVP (1 ) 能在阶段 G 1 逮捕房间周期并且禁止 cyclinB, cyclinD1 和 cyclinE 的 mRNA 表示。NVP (1 ) 压制了 cdk2 蛋白质表示,但是增加了 p27 和 p21 蛋白质表示。然而, NVP (1 ) 没改变 p16 蛋白质表示层次。NVP (1 ) 在由原子染色质冷凝作用显示了的 HepG2 房间支持了 apoptosis,并且另外,表明小径的细胞外的调整信号的 kinase (英皇家空军之阶级最低之兵) 被激活。而且,当 HepG2 房间是有英皇家空军之阶级最低之兵禁止者 PD98059 的 pretreated 时,津贴蛋白质表示水平被稀释。这些结果证明 NVP (1 ) 通过表明小径的英皇家空军之阶级最低之兵禁止 HepG2 的增长。NVP (1 ) 能是为肝癌症的潜在的药。Changdong Wang Peng Chen Hongjuan Jin Xu Yan Lu Gan Yi Li Shiyi Zhou Junli Chang Yuesheng Wang Guangxiao Yang Guangyuan He 2008Acta Biochimica et Biophysica Sinica2008,40,11:11
11Commissioning progress of the FAST显示文摘The Five-hundred-meter Aperture Spherical radio Telescope(FAST) was completed with its main structure installed on September 25, 2016, after which it entered the commissioning phase. This paper aims to introduce the commissioning progress of the FAST over the past two years. To improve its operational reliability and ensure effective observation time, FAST has been equipped with a real-time information system for the active reflector system and hierarchical commissioning scheme for the feed support system, which ultimately achieves safe operation of the two systems. For meeting the high-performance indices, a highprecision measurement system was set up based on the effective control methods that were implemented for the active reflector system and feed support system. Since the commissioning of the FAST, a low-frequency ultra-wideband receiver and 19-beam1.05-1.45 GHz receiver have been mainly used. Telescope efficiency, pointing accuracy, and system noise temperature were completely tested and ultimately achieved the acceptance indices of the telescope. The FAST has been in the process of national acceptance preparations and has begun to search for pulsars. In the future, it will still strive to improve its capabilities and expand its application prospects.Peng Jiang YouLing Yue HengQian Gan Rui Yao Hui Li GaoFeng Pan JingHai Sun DongJun Yu HongFei Liu NingYu Tang Lei Qian JiGuang Lu Jun Yan Bo Peng ShuXin Zhang QiMing Wang Qi Li Di Li 2019Science China(Physics,Mechanics & Astronomy)2019,62,5:11
12Effect of main inclusions on crack initiation in bearing steel in the very high cycle fatigue regime显示文摘This work aims to investigate the effect of main inclusions on crack initiation in bearing steel in the very high cycle fatigue(VHCF) regime. The size and type of inclusions in the steel were quantitatively analyzed, and VHCF tests were performed. Some fatigue cracks were found to be initiated in the gaps between inclusions(Al2 O3, Mg O-Al2 O3) and the matrix, while other cracks originated from the interior of inclusions(Ti N, Mn S). To explain the related mechanism, the tessellated stresses between inclusions and the matrix were calculated and compared with the yield stress of the matrix. Results revealed that the inclusions could be classified into two types under VHCF; of these two, only one type could be regarded as holes. Findings in this research provide a better understanding of how inclusions affect the high cycle fatigue properties of bearing steel.Chao Gu Yan-ping Bao Peng Gan Min Wang Jin-shan He 2018International Journal of Minerals,Metallurgy and Materials2018,25,6:11
13Achieving and maintaining biological nitrogen removal via nitrite under normal conditions显示文摘The principal aim of this paper is to develop an approach to realize stable biological nitrogen removal via nitrite under normal conditions. Validation of the new method was established on laboratory-scale experiments applying the sequencing batch reactor(SBR) activated sludge process to domestic wastewater with low C/N ratio. The addition of sodium chloride(NaCl) to influent was established to achieve nitrite build-up. The high nitrite accumulation, depending on the salinity in influent and the application duration of salt, was obtained in SBRs treating saline wastewater. The maintenance results indicated that the real-time SBRs can maintain stable nitrite accumulation, but conversion from shorter nitrification-denitrification to full nitrification-denitrification was observed after some operation cycles in the other SBR with fixed-time control. The presented method is valuable to offer a solution to realize and to maintain nitrogen removal via nitrite under normal conditions.CUI You-wei PENG Yong-zhen GAN Xiang-qing YE Liu WANG Ya-yi 2005Journal of Environmental Sciences2005,17,5:10
14Adefovir Dipivoxil plus Chinese Medicine in HBeAg-Positive Chronic Hepatitis B Patients:A Randomized Controlled 48-Week Trial显示文摘Objective:To evaluate the effects of a 48-week course of adefovir dipivoxil(ADV)plus Chinese medicine(CM)therapy,namely Tiaogan Jianpi Hexue(调肝健脾和血)and Tiaogan Jiedu Huashi(调肝解毒化湿)fomulae,in hepatitis B e antigen(HBeAg)-positive Chinese patients.Methods:A total of 605 HBeAg-positive Chinese CHB patients were screened and 590 eligible participants were randomly assigned to 2 groups in 1:1 ratio including experimental group(EG,received ADV plus CM)and control group(CG,received ADV plus CM-placebo)for 48 weeks.The major study outcomes were the rates of HBeAg and HBV-DNA loss on week 12,24,36,48,respectively.Secondary endpoints including liver functions(enzymes and bilirubin readings)were evaluated every 4 weeks at the beginning of week 24,36,and 48.Routine blood,urine,and stool analyses in addition to electrocardiogram and abdominal B scan were monitored as safety evaluations.Adverse events(AEs)were documented.Results:The combination therapy demonstrated superior HBeAg loss at 48 weeks,without additional AEs.The full analysis population was 560 and 280 in each group.In the EG,population achieved HBeAg loss on week 12,24,36,and 48 were 25(8.90%),34(12.14%),52(18.57%),and 83(29.64%),respectively;the equivalent numbers in the CG were 20(7.14%),41(14.64%),54(19.29%),and 50(17.86%),respectively.There was a statistically significant difference between two groups on week 48(P<0.01).No additional AEs were found in EG.Subgroup analysis suggested different outcomes among treatment patterns.Conclusion:Combination of CM and ADV therapy demonstrated superior HBeAg clearance compared with ADV monotherapy.The finding indicates that this combination therapy may provide an improved therapeutic effect and safety profile(ChiCTR-TRC-11001263).LI Xiao-ke ZHANG Ming-xiang SHAO Feng-zhen ZHOU Da-qiao XUE Jing-dong LIU Tie-jun CHI Xiao-ling LU Bing-jiu WANG Xian-bo LI Qin LI Jun MAO De-wen YANG Hua-sheng YANG Hong-zhi ZHAO Wen-xia LI Yong ZHANG Guo-liang ZHAO Yi-ming ZOU Jian-dong LIU Meng-yang ZHANG Ke-ke YANG Xian-zhao GAN Da-nan LI Ying ZHANG Peng LI Zhi-guo LI Shuo YE Yong-an 2020Chinese Journal of Integrative Medicine2020,26,5:9
15Hard X-ray Imager (HXI) onboard the ASO-S mission显示文摘Hard X-ray Imager(HXI)is one of the three scientific instruments onboard the Advanced Spacebased Solar Observatory(ASO-S)mission,which is proposed for the 25th solar maximum by the Chinese solar community.HXI is designed to investigate the non-thermal high-energy electrons accelerated in solar flares by providing images of solar flaring regions in the energy range from 30 keV to 200 keV.The imaging principle of HXI is based on spatially modulated Fourier synthesis and utilizes about 91 sets of bi-grid sub-collimators and corresponding LaBr3 detectors to obtain Fourier components with a spatial resolution of about 3 arcsec and a time resolution better than 0.5 s.An engineering prototype has been developed and tested to verify the feasibility of design.In this paper,we present background,instrument design and the development and test status of the prototype.Zhe Zhang Deng-Yi Chen Jian Wu Jin Chang Yi-Ming Hu Yang Su Yan Zhang Jian-Ping Wang Yao-Ming Liang Tao Ma Jian-Hua Guo Ming-Sheng Cai Yong-Qiang Zhang Yong-Yi Huang Xiao-Yan Peng Zong-Bin Tang Xuan Zhao Hong-He Zhou Lian-Guo Wang Jing-Xing Song Miao Ma Guang-Zhou Xu Jian-Feng Yang Di Lu Ying-Hong He Jin-You Tao Xiao-Long Ma Bao-Gang Lv Yan-Ping Bai Cai-Xia Cao Yu Huang Wei-Qun Gan 2019Research in Astronomy and Astrophysics2019,19,11:9
16Branched glycerol dialkyl glycerol tetraethers and paleoenvironmental reconstruction in Zoigê peat sediments during the last 150 years显示文摘Branched glycerol dialkyl glycerol tetraethers (GDGTs) were analyzed in peat samples taken from the Zoigê grassland, located on the eastern margin of the Qinghai-Tibetan Plateau. The mean annual air temperature (MAAT) and pH in the 210 Pb-dating peat core were reconstructed based on the cyclization of branched tetraethers (CBT) and methylation of branched tetraethers (MBT) indices for the last 150 years. The results showed that the MAAT and pH values involved three stages of variation over the last 150 years. The pH was stable and the MAAT decreased slowly by about 1°C from 1851 to 1927. The pH decreased rapidly by 0.6 and the MAAT decreased significantly by 2.5°C between 1927 and 1979. The pH and MAAT increased by 0.8 and 5°C, respectively, since the 1980s. The reconstructed temperatures correspond well to the mean winter temperatures reconstructed using tree-rings from the Jiuzhaigou Valley, situated at the boundary between the Qinghai-Tibetan Plateau and the Sichuan Basin. The estimated MAAT was similar to the temperatures reconstructed using tree-rings, indicating an increasing trend, as shown by local instrumental records from 1957 to 2001. These results provide further confidence in the application of proxies based on glycerol dialkyl glycerol tetraethers in peat records for continental paleoclimate reconstruction.ZHOU HaoDa HU JianFang MING LiLi PENG PingAn ZHANG Gan 2011Chinese Science Bulletin2011,56,23:9
17Advances in research of the mid-deep South China Sea circulation显示文摘The South China Sea(SCS)is a large marginal sea connecting the Indian and Pacific oceans.Under the factors of monsoons,strait transport,and varied bathymetry,the SCS presents a three-layer structure and strong diapycnal mixing which is far greater than that in the open ocean.Theoretical analysis and observations reveal that internal tides,internal solitary waves,and strong winds are the sources of the strong mixing in the northern SCS.A major consequence of the strong mixing is an active mid-deep circulation system.This system promotes exchange of water between the SCS and adjacent oceans,and also regulates the upper layer of wind-driven circulation,making the 3 dimensional SCS circulation clearly different from that in other tropical and subtropical marginal seas.The mass transport capacity of the mid-deep circulation has a substantial impact on marine sedimentation,the biogeochemical cycle,and other processes in the SCS.This paper summarizes the recent advances in middeep sea circulation dynamics of the SCS,and discusses the opportunities and challenges in this area.Dongxiao WANG Qiang WANG Shuqun CAI Xiaodong SHANG Shiqiu PENG Yeqiang SHU Jingen XIAO Xiaohui XIE Zhiwei ZHANG Zhiqiang LIU Jian LAN Dake CHEN Huijie XUE Guihua WANG Jianping GAN Xinong XIE Rui ZHANG Hui CHEN Qingxuan YANG 2019Science China Earth Sciences2019,62,12:8
18Noise-sidebands-free and ultra-low-RIN 1.5 μm single-frequency fiber laser towards coherent optical detection显示文摘A noise-sidebands-free and ultra-low relative intensity noise(RIN) 1.5 μm single-frequency fiber laser is demonstrated for the first time to our best knowledge. Utilizing a self-injection locking framework and a booster optical amplifier, the noise sidebands with relative amplitudes as high as 20 dB are completely suppressed.The RIN is remarkably reduced by more than 64 dB at the relaxation oscillation peak to retain below-150 dB∕Hz in a frequency range from 75 kHz to 50 MHz, while the quantum noise limit is -152.9 d B∕Hz.Furthermore, a laser linewidth narrower than 600 Hz, a polarization-extinction ratio of more than 23 dB, and an optical signal-to-noise ratio of more than 73 dB are acquired simultaneously. This noise-sidebands-free and ultralow-RIN single-frequency fiber laser is highly competitive in advanced coherent light detection fields including coherent Doppler wind lidar, high-speed coherent optical communication, and precise absolute distance coherent measurement.QILAI ZHAO ZHITAO ZHANG BO WU TIANYI TAN CHANGSHENG YANG JIULIN GAN HUIHUI CHENG ZHOUMING FENG MINGYING PENG ZHONGMIN YANG SHANHUI XU 2018Photonics Research2018,6,4:7
19Highly Transparent and Colorless Polyimide Film with Low Dielectric Constant by Introducing Meta-substituted Structure and Trifluoromethyl Groups显示文摘An effective design strategy for preparing highly transparent polyimide film with low dielectric constant is presented.The key to the strategy is to simultaneously introduce meta-substituted structure and trifluoromethyl in polymer chains.By using this design strategy,a highly transparent polyimide film with low-k was synthesized from 3,5-diaminobenzotrifluoride(m-TFPDA)and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride(6FDA)through a two-step method.The obtained m-TFPDA/6FDA(CPI)film(~30 pm)possesses high optical transparency(λ_(cutoff)=334 nm,T_(450nm)=85.26%,Haze=0.31)and is close to colorless(L^(*)=96.03,a^(*)=-0.34,b^(*)=2.12,yellow index=3.96).The intrinsic k and dielectric loss value of the film are 2.27 and 0.0013 at 10 kHz,respectively.More importantly,such low dielectric performance could remain stable up to 280℃,and the film shows a low moisture rate(~0.51%),which helps to maintain the low-k property stability in different humid environments.Meanwhile,the film also shows good thermal stability and mechanical properties,with a glass transition temperature(T_(g))of 296℃and the 5 wt%decomposition temperature(T_(d,s%))of 522℃under N_(2).The tensile strength and tensile modulus of the film are 85.1 MPa and 1.96 GPa,respectively.In addition,the film is soluble in common solvents,which allows simple solution processing and low-cost,continuous roll-to-roll processes.This design strategy is beneficial to improving the transparency,lightening yellow color,lowering the dielectric constant and meanwhile maintaining the comprehensive properties of polyimide films,which is mainly due to the introduced meta-substituted and trifluoromethyl structures effectively inhibiting the transfer of charge transfer complex(CTC)effects and increasing the free volume of film.This design strategy could also be extended to other high-performance polymer systems.Hong-Tao Zuo Feng Gan Jie Dong Peng Zhang Xin Zhao Qing-Hua Zhang 2021Chinese Journal of Polymer Science2021,39,4:6
20The Lyman-alpha Solar Telescope(LST) for the ASO-S mission——Ⅱ. design of LST显示文摘As one of the three payloads for the Advanced Space-based Solar Observatory(ASO-S)mission,the Lyman-alpha(Lyα)Solar Telescope(LST)is composed of three instruments:a Solar Corona Imager(SCI),a LyαSolar Disk Imager(SDI)and a full-disk White-light Solar Telescope(WST).When working in-orbit,LST will simultaneously perform high-resolution imaging observations of all regions from the solar disk to the inner corona up to 2.5 R⊙(R⊙stands for the mean solar radius)with a spatial resolution of 4.8′′and 1.2′′for coronal and disk observations,respectively,and a temporal resolution of 30–120 s and 1–120 s for coronal and disk observations,respectively.The maximum exposure time can be up to20 s due to precise pointing and image stabilization function.Among the three telescopes of LST,SCI is a dual-waveband coronagraph simultaneously and independently observing the inner corona in the HI Lyα(121.6±10 nm)line and white light(WL)(700±40 nm)wavebands by using a narrowband Lyαbeam splitter and has a field of view(FOV)from 1.1 to 2.5 R⊙.The stray-light suppression level can attain<10^-6 B⊙(B⊙is the mean brightness of the solar disk)at 1.1 R⊙and≤5×10^-8 B⊙at 2.5 R⊙.SDI and WST are solar disk imagers working in the Lyαline and 360.0 nm wavebands,respectively,which adopt an off-axis two-mirror reflective structure with an FOV up to 1.2 R⊙,covering the inner coronal edge area and relating to coronal imaging.We present the up-to-date design for the LST payload.Bo Chen Hui Li Ke-Fei Song Quan-Feng Guo Pei-Jie Zhang Ling-Ping He Shuang Dai Xiao-Dong Wang Hai-Feng Wang Chun-Long Liu Hong-Ji Zhang Guang Zhang Yunqi Wang Shi-Jie Liu Hong-Xin Zhang Lei Liu Shi-Lei Mao Yang Liu Jia-Hao Peng Peng Wang Liang Sun Yang Liu Zhen-Wei Han Yan-Long Wang Kun Wu Guang-Xing Ding Peng Zhou Xin Zheng Ming-Yi Xia Qing-Wen Wu Jin-Jiang Xie Ya Chen Shu-Mei Song Hong Wang Bo Zhu Chang-Bo Chu Wen-Gang Yang Li Feng Yu Huang Wei-Qun Gan Ying Li Jing-Wei Li Lei Lu Jian-Chao Xue Bei-Li Ying Ming-Zhe Sun Cheng Zhu Wei-Min Bao Lei Deng Zeng-Shan Yin 2019Research in Astronomy and Astrophysics2019,19,11:6
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