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1Characterization of microRNAs in serum: a novel class of biomarkers for diagnosis of cancer and other diseases显示文摘在各种各样的纸巾的 microRNAs (miRNAs ) 的 Dysregulated 表示与许多疾病被联系了,包括癌症。这里,我们证明 miRNAs 在象老鼠,老鼠,牛的胎儿,小牛,和马那样的人和另外的动物的浆液和血浆是在场的。在浆液的 miRNAs 的层次在一样的种类的个人之中稳定、可再现、一致。采用 Solexa,我们定序健康中国题目的所有浆液 miRNAs 并且分别地在男、女的题目发现超过 100 和 91 浆液 miRNAs。我们也为肺癌症, colorectal 癌症,和糖尿病识别了浆液 miRNAs 的特定的表示模式,提供证据那浆液 miRNAs 为各种各样的疾病包含指纹。癌症特定的浆液 miRNAs 由 Solexa 获得了的二个非小的房间肺进一步在 75 个健康施主和 152 个癌症病人的独立审判被验证,用量的反向的抄写聚合酶链反应试金。通过这些分析,我们断定浆液 miRNAs 能为各种各样的癌症和另外的疾病的察觉用作潜在的 biomarkers。Xi Chen Yi Ba Lijia Ma Xing Cai Yuan Yin Kehui Wang Jig ang Guo Yujing Zhang Jiangning Chen Xing Guo Qibin Li Xiaoying Li Wenjing Wang Yan Zhang Jin Wang Xueyuan Jiang Yang Xiang Chen Xu Pingping Zheng Juanbin Zhang Ruiqiang Li Hongjie Zhang Xiaobin Shang Ting Gong Guang Ning Jun Wang Ke Zen Junfeng Zhang Chen-Yu Zhang 2008Cell Research2008,18,10:975
2Mammalian WTAP is a regulatory subunit of the RNA N6-methyladenosine methyltransferase显示文摘包含 methyltransferase 建筑群的象 3 一样的 methyltransferase (METTL3 ) 催化 N6-methyladenosine (m6A ) 形成,一个新奇 epitranscriptomic 标记;然而,这建筑群的性质仍然保持大部分未知。这里,我们报导人的 m6A methyltransferase 建筑群, Wilm 的肿瘤 1 伙伴蛋白质(WTAP ) 和象 14 一样的 methyltransferase (METTL14 ) 的二个新部件。WTAP 与 METTL3 和 METTL14 交往,并且为他们的本地化被要求进在 vivo 与处理因素的 pre-mRNA 并且为 m6A methyltransferase 的催化活动充实的原子点缀。RNA 的多数在 vivo 由 WTAP 和 METTL3 跳了代表包含一致 m6A 主题的 mRNAs。当 WTAP 不在时, METTL3 的 RNA 有约束力的能力强烈被减少,建议 WTAP 可以工作调整到 mRNA 目标的 m6A methyltransferase 建筑群的招募。而且,在有 photoactivatable-ribonucleoside-enhanced crosslinking 和 immunoprecipitation (同等片断) 的联合的 transcriptomic 分析说明那 WTAP 和 METTL3 调整涉及抄写并且 RNA 处理的基因拼接的表示和选择。在 zebrafish 胚胎的调停 Morpholino 的击倒的指向 WTAP 或 METTL3 引起了织物区别缺点并且增加了 apoptosis。这些调查结果提供 WTAP 可以在 m6A methyltransferase 建筑群作为一个规章的子单元工作并且在 RNA 的 epitranscriptomic 规定起一个关键作用的充分证据新陈代谢。Xiao-Li Ping Bao-Fa Sun Lu Wang Wen Xiao Xin Yang Wen-Jia Wang Samir Adhikari Yue Shi Ying Lv Yu-Sheng Chen Xu Zhao Ang Li Ying Yang Ujwal Dahal Xiao-Min Lou Xi Liu Jun Huang Wei-Ping Yuan Xiao-Fan Zhu Tao Cheng Yong-Liang Zhao Xinquan Wang Jannie M Rendtlew Danielsen Feng Liu Yun-Gui Yang 2014Cell Research2014,24,2:244
3Stable classi?cation with limited sample: transferring a 30-m resolution sample set collected in 2015 to mapping 10-m resolution global land cover in 2017显示文摘As the world strives to reduce the impact of population growth, urbanization, agricultural expansion, and climate change on food security, energy and water shortage, resource over-exploration, biodiversity loss, environmental pollution, and ultimately human health, timely and higher resolution land cover information is urgently needed to achieve the sustainable development goals of the United Nations.Peng Gong Han Liu Meinan Zhang Congcong Li Jie Wang Huabing Huang Nicholas Clinton Luyan Ji Wenyu Li Yuqi Bai Bin Chen Bing Xu Zhiliang Zhu Cui Yuan Hoi Ping Suen Jing Guo Nan Xu Weijia Li Yuanyuan Zhao Jun Yang Chaoqing Yu Xi Wang Haohuan Fu Le Yu Iryna Dronova Fengming Hui Xiao Cheng Xueli Shi Fengjin Xiao Qiufeng Liu Lianchun Song 2019Science Bulletin2019,64,6:166
4Association of H.pylori infection with gastric carcinoma:a Meta analysis显示文摘AIM: To follow the principles of evidence based medicine to reach the integrated results of these studies.METHODS: Twenty-one papers of case-control studies were selected, including 11 on gastric cancer, 7 on precancerous lesion of stomach and 3 on lymphoma of stomach: Meta analysis was used to sum up the odds ratios (OR) of these studies.RESULTS: H. Pylori vsgastric cancer (intestinal and diffuse type): the odds ratio from the fixed effect model is 3.0016(95% Cl 2.4197-3.7234, P < 0.001 ). H. Pylori vs precancerous lesion of stomach: a random effect model was used to calculate the summary odds ratio and its value is 2.5635 (95% Cl: 1.8477-3.5566, P < 0.01). H. Pylori vs lymphoma of stomach: though the quantity of literature is too small to make Meta analysis, the data of these 3 studies show that lymphoma of stomach is highly associated with H. Pylori infections.CONCLUSION: Since it had been revealed that H. Pylori infection pre-exists in gastric carcinoma and precancerous lesions, the results of Meta analysis present a strong evidence to support the conclusion that H. Pylori infection is a risk factor for gastric carcinoma.Fu-Bo Xue~1 Yong-Yong Xu~1 Yi Wan~1 Bo-Rong Pan~2 Jun Ren~2 Dai-Ming Fan~3 1 Department of Health Statistics,Department of2 Oncology3 Gastroenterology of XiJing Hospital,the Fourth Military Medical University,Xi’an 710032,Shaanxi Province,China 2001World Journal of Gastroenterology2001,7,6:66
5Analysis of in vivo patterns of caspase 3 gene expression in primary hepatocellular carcinoma and its relationship to p21^(WAF1) expression and hepatic apoptosis显示文摘AIM To detect the expression of caspase 3gene in primary human hepatocellular carcinoma(HCC)and investigate its relationship to p21WAF1gene expression and HCC apoptosis.METHODS In situ hybridization was employedto determine caspase 3 and p21WAF1expression inHCC.In situ end-labeling was used to detecthepatocytic apoptosis in HCC.RESULTS Twenty-one of 39(53.8%)cases ofHCC were found to express caspase 3transcripts,while 45.2% of HCC failed toexpress caspase 3.Non-cancerous adjacent livertissues showed more positive caspase 3(87.5%,7/8)as compared with HCC(P<0.05).The expression of caspase 3 is correlated withHCC differentiation,72.2%(13/18)ofmoderately to highly differentiated HCC showedcaspase 3 transcripts positive,while only 38.1%of poorly differentiated HCC harbored caspase 3transcripts(P<0.05).No relationship wasfound between caspase 3 expression and tumorsize or grade or metastasis,although 52.5%(5/8)of HCC with metastasis were caspase 3positive and a little higher than that with nometastasis(51.6%,P>0.05).Expression of caspase 3 alone did not affect the apoptosisindex(AI)of HCC.The AI was 7.12%o in caspase3-positive tumors(n=21),while in caspase 3-negative cases(n=18)6.59%0(P>0.05).Expression of caspase 3 clearly segregated withp21WAF1positive tumors as compared withp21WAF1-negative cases(16 of 23,69.6% versus5 of 16,31.3%)with statistical significance(P=0.017).In the cases with positive caspase 3and negative p21WAF1,the Al was found slightlyhigher,but with no statistical significance,thanthat with expression of p21WAF1and caspase 3(7.21‰ vs 6.98‰,P>0.05).CONCLUSION Loss of caspase 3 expressionmay contribute to HCC carcinogenesis,althoughthe expression of caspase 3 does not correlatewell with cell apoptosis in HCC.p21WAF1may bemerely one of the inhibitors which can reducecaspase 3 mediated cell apoptosis in HCCs.Bao Hua Sun Jun Zhang Bao JǜWang Xi Ping Zhao You Kun Wang Zhi Qun Yu Dong Liang Yang Lian Jie Hao Department of Clinical Immunology,Tongji Hospital,Tongji Medical University,Wuhan 430030,Hubei Province,China 2000World Journal of Gastroenterology2000,6,3:65
6Astragalus polysaccharide enhances immunity and inhibits H9N2 avian influenza virus in vitro and in vivo显示文摘This study investigated the humoral immunization of Astragalus polysaccharide(APS) against H9N2 avian influenza virus(H9N2 AIV) infection in chickens. The effects of APS treatment on H9N2 infection was evaluated by an MTT [3(4, 5-dimethylthiazol-2-yl)-2, 3-diphenyl tetrazolium bromide] assay and analysis of MHC and cytokine mRNA expression. The effect on lymphocyte and serum antibody titers in vivo was also investigated. IL-4, IL-6, IL-10, LITAF, IL-12 and antibody titers to H9N2 AIV were enhanced in the first week after APS treatment. The results indicated that APS treatment reduces H9N2 AIV replication and promotes early humoral immune responses in young chickens.Sanpha Kallon Xiaorong Li Jun Ji Cuiying Chen Qianyun Xi Shuang Chang Chunyi Xue Jingyun Ma Qingmei Xie Youngliang Zhang 2013Journal of Animal Science and Biotechnology2013,4,4:48
7Programmable time-domain digital-coding metasurface for non-linear harmonic manipulation and new wireless communication systems显示文摘Optical non-linear phenomena are typically observed in natural materials interacting with light at high intensities, and they benefit a diverse range of applications from communication to sensing. However,controlling harmonic conversion with high efficiency and flexibility remains a major issue in modern optical and radio-frequency systems. Here, we introduce a dynamic time-domain digital-coding metasurface that enables efficient manipulation of spectral harmonic distribution. By dynamically modulating the local phase of the surface reflectivity, we achieve accurate control of different harmonics in a highly programmable and dynamic fashion, enabling unusual responses, such as velocity illusion. As a relevant application, we propose and realize a novel architecture for wireless communication systems based on the time-domain digital-coding metasurface, which largely simplifies the architecture of modern communication systems, at the same time yielding excellent performance for real-time signal transmission. The presented work, from new concept to new system, opens new pathways in the application of metamaterials to practical technology.Jie Zhao Xi Yang Jun Yan Dai Qiang Cheng Xiang Li Ning Hua Qi Jun Chen Ke Guo Dong Bai Shuo Liu Shi Jin Andrea Alù Tie Jun Cui 2019National Science Review2019,6,2:46
8The vegetation and climate change during Neocene and Early Quaternary in Jiuxi Basin, China显示文摘Sporopollen record in the Laojunmiao Section at Yumen in the Hexi Corridor foreland depression at the northern margin of the Tibetan Plateau revealed that during the period of 13.0―11.15 Ma the ecological environment of the Jiuxi Basin is characterized by steppe vegetation and a semi-moist climate. During 11.16―8.60 Ma prevailed forests of cypress and a still warmer, moister climate; steppe vegetation and dry climate began probably at about 8.6 Ma. Although aridification had been relaxed time and again during 8.40―6.93 Ma (forest-steppe, warm-semi-moist), 6.64―5.67 Ma (open-forest and steppe, warmer-semi-moist) and 5.42―4.96 Ma (steppe, semi-arid), the climate in the region became drier and drier in response to the fre- quent occurrence of aridity during 6.93―6.64 Ma (steppe, semi-arid), 5.67―5.42 Ma (de- sert-steppe, arid), 3.66―3.30 Ma (desert-steppe, arid) and 2.56―2.21 Ma (desert, arid). Perhaps the important findings of our study are the notable expansion of drought-enduring plants during 3.66―3.30 Ma and about 2.56 Ma and the replacement of vegetation by vast arid desert.MA Yuzhen 1 , FANG Xiaomin 1,2 , LI Jijun 1 , WU Fuli 1 & ZHANG Jun 1 1. Key Laboratory of Western China’s Environmental Systems and College of Resources and Environment, Lanzhou University, Lanzhou 730000, China 2. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 2005Science China Earth Sciences2005,48,5:31
9Assessment of duodenogastric reflux by combined continuous intragastric pH and bilirubin monitoring显示文摘AIM: To assess the diagnostic value of a combination of continuous intragastric pH and bilirubin monitoring in the detection of duodenogastric reflux (DGR), and the effects of diet on the bilirubin absorbance.METHODS: 30 healthy volunteers were divided into twogroups: standard diet group (Group 1) 18 cases, free diet group (Group 2) 12 cases. Each subjects were subjected to simultaneous 24 hour intragastric pH and spectrophotometric bilirubin concentration monitoring (Bilitec 2000).RESULTS: There was no difference of preprandial phasebilirubin absorbance between two groups. The absorbanceof postprandial phase was significantly increased in group 2than group 1. There was no difference between preprandialphase and postprandial phase absorbance in group 1.Postprandial phase absorbance was significantly higher ingroup 2. In a comparison of bile reflux with intragastric pHduring night time, there were 4 types of reflux:Simultaneous increase in absorbance and pH in only 19.6%, increase in bilirubin with unchanged pH 33. 3 %, pHincrease with unchanged absorbance 36. 3 %, and bothunchanged in 10. 8 %. Linear regression analysis showed nocorrelation between percertage total time of pH < 4 aridpercentage total time of absortance > 0. 14, r=0.068, P<0.05.CONCLUSION: Because of the dietary effect, highabsorbance fluids or foods should be avoided in detection.Intrsgastric pH and bilirubin monitoring separately predictthe presence of duodenal (and/or pancreatic) reflux and bilereflux. They can not substitute for each other. The detectionof DGR is improved if the two parameters are combinedsimultanoously.Fei Dai Jun Gong Ru Zhang Jin-Yan Luo You-Ling Zhu Xue-Qin Wang,Department of Gastroenterology,Second Hospital of Xi’ an Jiaotong University,Xi’an 710004,Shaanxi Province,China 2002World Journal of Gastroenterology2002,8,2:30
10A highly active oxygen evolution electrocatalyst: Ultrathin CoNi double hydroxide/CoO nanosheets synthesized via interface-directed assembly显示文摘成本效率、稳定的氧进化 electrocatalyst 为改进精力存储和变换效率是必要的。此处, 2D nanosheets 与随机 cross-linked CoNi 分层的双氢氧化物(LDH ) 并且小咕咕叫 nanocrystals 被设计并且综合经由在在空中的 situ 减小和 interfacedirected 汇编。CoNi LDH/CoO nanosheets 的形成被归因于界面的紧张驾驶的含水的 metaloxide 簇的强壮的挤出。获得了松开、多孔的 nanosheets 由于众多的缺点的存在展出了低 crystallinity。由于在金属 3d 和 O 2p 之间的轨道的杂交, orbitals,和电子在在场的 CoNi LDH 通过 NiOCo,很多个公司和 Ni 原子在金属原子之间转一个高 +3 原子价。在氧进化反应(OER ) 的高密度的这些唯一的特征结果活跃地点,改进与的亲密关系哦 和催化剂,并且为离子吸附和运输导致一个大可存取的表面区域和可渗透的隧道。因此,产生 nanosheets 向 OER 展出了高催化的活动。CoNi LDH/CoO 在碱的媒介展示了 1.48 V 的一个低发作潜力,并且在 10 妈据獥漠 ? 楬桧 ?L 潳灲楴湯漠 ? 桴 ? 的当前的密度要求了仅仅 300 mV 的过电位 ?? 潢瑴浯摥琠慲獮業瑴湡散吗??Jun Wu Zhiyu Ren Shichao Du Lingjun Kong Bowen Liu Wang Xi Jiaqing Zhu Honggang Fu 2016Nano Research2016,9,3:25
11Prevalence of Thyroid Nodules and Its Relationship with Iodine Status in Shanghai:a Population-based Study显示文摘Objective This study was designed to evaluate the prevalence of thyroid nodules(TNs) and its relationship with urine iodine concentrations(UICs) after the regional rapid economic growth and lifestyle changes. Methods A cross-sectional survey was conducted in the general population aged 15-69 years. A questionnaire regarding general and personal characteristics and relevant information was administered. Ultrasonography of the thyroid was performed, and serum triiodothyronine(T3), tetraiodothyronine(T4), serum thyroid stimulating hormone(TSH), free triiodothyronine(FT3), free tetraiodothyronine(FT4), thyroglobulin antibody(Tg Ab), thyroid peroxidase antibody(TPOAb), and TSH receptor antibody(TRAb) levels were measured for each individual subject. Results The prevalence rates of TNs in the whole population, females and males were 27.76%, 34.04%, and 21.60%, respectively. The prevalence of multiple nodules increased with age, whereas the prevalence peaks differed between males and females. The median UICs in the whole population and females with non-TNs were higher than those of subjects with TNs(P=0.0035, P=0.0068). The median UICs in subjects with a single TN were higher than those in subjects with multiple TNs(P=0.0164, P=0.0127). The result showed a U-shaped curve relationship between UIC and prevalence of TNs. The prevalence of TNs was the lowest when the UIC was 140-400 μg/L. Conclusion The prevalence of TNs was nearly 30% and increased with age. The relationship between UIC and prevalence of TNs is U-shaped, with an increase in risk when the UIC was <140 μg/L and >400 μg/L. Very low or high UIC levels need attention and correction.SONG Jun ZOU Shu Rong GUO Chang Yi ZANG Jia Jie ZHU Zhen Ni MI Ming HUANG Cui Hua YU Hui Ting LU Xi RUAN Ye WU Fan 2016Biomedical and Environmental Sciences2016,29,6:25
12Expression of regulating apoptosis gene and apoptosis index in primary liver cancer显示文摘INTRODUCTIONProgramed cell death plays an important role in thegenesis of cancer.Certain cancer genes canregulate apoptosis.Recently,several proteins thatare structurally related to Bcl-2,an inhibitor ofapoptosis,have been identified.Therefore,novel strategies and agents that target specificmolecular pathways,as well as triggering aHong Yu Xu You Lin Yang Xi Li Guan Guang Song Ai Min Jiang Li Jun Shi 2000World Journal of Gastroenterology2000,6,5:21
13Preparation and activity of conjugate of monoclonal antibody HAb18 against hepatoma F( ab′ )_2 fragment and staphylococcal enterotoxin A显示文摘AIM To prepare the conjugate of staphylococcal enterotoxin A (SEA) protein which is a bacterial SAg and the F(ab')2 fragment of mAb HAbl8 against human hepatocellular carcinoma (HCC), and identify its activity in order to use SAg in the targeting therapy of HCC.METHODS MAb HAbl8 was extracted from the abdominal dropsy of Balb/ c mice, and was purified through chromatography column SP-40HR with Fast protein liquid chromatography (FPLC) system. The F(ab')2 fragment of mAb HAb18 was prepared by papainic digestion method. The conjugate of mAb HAb18 F(ab')2fragment and SEA was prepared with chemical conjugating reagent N-succinimidyl-3-( 2-pyridyldithio) propionate (SPDP) and purified through chromatography column Superose 12with FPLC system. The molecular mass and purity of each collected peak were identified with SDS-PAGE assay. The protein content was assayed by Lowry's method. The antibody activity of HAb18 F (ab')2 against HCC in the conjugate was identified by indirect immunocytochemical ABC method, and the activity of SEA in the conjugate to activate peripheral blood mononuclear cells (PBMC) was identified with MTT assay.RESULTS The lgG mAb HAb18 was extracted,and purified successfully. Immunocytochemical staining demonstrated that it reacted with most of HHCC cells of human HCC cell line. There were two peaks in the process of purification of the prepared HAb18 F(ab)2-SEA conjugate. SDS-PAGE assay demonstrated that the molecular mass of the first peak was about 130 ku, and the second peak was the mixture of about 45 ku and a little 100 ku proteins. The immunocytochemical staining was similar in HAb18 F (ab ')2-SEAconjugate and HAb18 F (ab ')2, i.e., thecytoplasm and/or cell membranes of most HHCC cells were positively stained. The MTT assay showed that the optical absorbance (A) value at 490 nm of HAb18 F (ab')2-SEA conjugate was 0.182 ± 0.012, that of negative control was 0.033± 0.009, and there was significant difference between them ( P < 0.05).CONCLUSION SPDP is a good proteinconjugating reagent and can be used in preparing protein conjugate. The conjugate of mAb HAb18F(ab')2 fragment and SEA protein was preparedsuccessfully in present study and can be used in the experimental study of HCC targeting therapy with the conjugate of SAg and anti-HCC mAbs or their fragments.Lian Jun Yang Yan Fang Sui Zhi Nan Chen Department of Pathology, Fourth Military Medical University. Xi’an 710032, Shaanxi Province, China 2001World Journal of Gastroenterology2001,7,2:20
14Alkaloid from Dicranostigma leptopodum(Maxim) Fedde显示文摘Fedde 有的 Dicranostigma leptopodum (格言) 的整个植物的 Phytochemical 调查导致五碱的隔离:dicranostigmine (1 ) , isocorydine (2 ) , corydine (3 ) , protopine (4 ) 和 sinoacutine (5 ) 。Oxomorphine 碱(5 ) 第一次从类 Dicranostigma 被孤立,新复合结构(1 ) 被各种各样的分光镜的方法包括 2D NMR 技术(gCOSY, HMQC, HMBC 和 NOESY ) 和 HRESIMS 阐明。Yan Dang Hong Fei Gong Jun Xi Liu Si Jiu Yu 2009Chinese Chemical Letters2009,20,10:19
15Pathogenesis of acute lung injury in rats with severe acute pancreatitis显示文摘BACKGROUND: Acute lung injury (ALI) is the most common and severe complication of severe acute pancreatitis (SAP). The elucidation of the mechanism of ALI contributes to the diagnosis and treatment of the illness. In this study, we studied the pathogenesis of ALI in rats with severe acute pancreatitis. METHODS: The rats were sacrificed at 1, 3, 5, 6, 9 and 12 hours after the establishment of the model of SAP. Pancreas and lung tissues were obtained for pathological study, and examination of microvascular permeability and myeloperoxidase (MPO) examination. The gene expressions of tumor necrosis factor-α (TNF-α) and intercellular adhesion molecule-1 (ICAM-1) in the pancreas and lung tissues were detected by reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: After the establishment of the SAP model, the degree of pancreatic and lung injury increased gradually along with the gradual increase of MPO activity and micro-vascular permeability. Gene expressions of TNF-α and ICAM-1 in the pancreas rose at 1 hour and peaked at 7 hours. In contrast, their gene expression in the lungs rose slightly at 1 hour and peaked at 9-12 hours. CONCLUSION: An obvious time window existed between SAP and lung injury, which is beneficial to the early prevention of the development of ALI.Xue-Min Liu, Jun Xu and Zi-Fa Wang Department of Hepatobiliary Surgery, First Hospital, Xi’an Jiaotong University, Xi’an 710061 , China 2005Hepatobiliary & Pancreatic Diseases International2005,4,4:18
16MHD Flow Control of Oblique Shock Waves Around Ramps in Low-temperature Supersonic Flows显示文摘This article is devoted to experimental study on the control of the oblique shock wave around the ramp in a low-temperature supersonic flow by means of the magnetohydrodynamic(MHD) flow control technique.The purpose of the experiments is to take advantage of MHD interaction to weaken the oblique shock wave strength by changing the boundary flow characteristics around the ramp.Plasma columns are generated by pulsed direct current(DC) discharge,the magnetic fields are generated by Nd-Fe-B rare-earth permanent magnets and the oblique shock waves in supersonic flow are generated by the ramp.The Lorentz body force effect of MHD interaction on the plasma-induced airflow velocity is verified through particle image velocimetry(PIV) measurements.The experimental results from the supersonic wind tunnel indicate that the MHD flow control can drastically change the flow characteristics of the airflow around the ramp and decrease the ratio of the Pitot pressure after shock wave to that before it by up to 19.66%,which leads to the decline in oblique shock wave strength.The oblique shock waves in front of the ramp move upstream by the action of the Lorentz body force.The discharge characteristics are analyzed and the MHD interaction time and consumed energy are determined with the help of the pulsed DC discharge images.The interaction parameter corresponding to the boundary layer velocity can reach 1.3 from the momentum conservation equation.The velocity of the plasma column in the magnetic field is much faster than that in the absence of magnetic field force.The plasma can strike the neutral gas molecules to transfer momentum and accelerate the flow around the ramp.Su Changbing,Li Yinghong,Cheng Bangqin,Wang Jian,Cao Jun,Li Yiwen Engineering College,Air Force Engineering University,Xi’an 710038,China 2010Chinese Journal of Aeronautics2010,23,1:15
17Impact of the Three Gorges Project operation on the water exchange between Dongting Lake and the Yangtze River显示文摘The Three Gorges Project(TGP) is a world known project to utilize and manage the water resources of the Yangtze River. The reservoir stores water at the end of the flood season, and replenishes downstream reaches with water in dry seasons. In addition to such benefits, the TGP has irreversibly changed the hydrological process and the river-lake relation of the middle and lower reaches. In this paper, a hydrodynamic model was established to quantify the impact of the TGP's operation on the water exchange between Dongting Lake and the Yangtze River during 2009-2013. The results indicated that:the operation of the TGP has considerably reduced the peak discharge and the flood volume of the main stream and the Dongting Lake area. The inflow volume from the Yangtze River to Dongting Lake via three outlets decreased by 1.9-3.5 billion m^3/yr, while the outflow volume from Dongting Lake to the Yangtze River at Chenglingji increased by 0.3-1.6 billion m^3 in September and 0.4-0.6 billion m^3 in October,respectively. This research provides valuable information for flood control, irrigation, and water allocation in the middle and lower reaches of the Yangtze River, and serves as a typical case for investigating the impact of other hydropower projects around the world.Minglong Dai Jun Wang Mingbo Zhang Xi Chen 2017International Journal of Sediment Research2017,32,4:14
18A single Eu^(2+)-activated high-color-rendering oxychloride white-light phosphor for white-light-emitting diodes显示文摘Single-phased,high-color-rendering index(CRI)white-light phosphors are emerging as potential phosphor-converted white-light-emitting diodes(WLEDs)and as an alternative to blends of tricolor phosphors.However,it is a challenge to create a high CRI white light from a single-doped activator.Here,we present a high CRI(Ra 591)white-light phosphor,Sr_(5)(PO_(4))_(3-x)(BO_(3))_(x)Cl:Eu^(2+),composed of Sr5(PO4)3Cl as the beginning member and Sr_(5)(BO_(3))_(3)Cl as the end member.This work utilized the solid-solution method,and tunable Eu^(2+) emission was achieved.Color-tunable Eu^(2+) emissions in response to structural variation were observed in Sr_(5)(PO_(4))_(3-x)(BO_(3))_(x)Cl solid solutions.This was further confirmed using X-ray Rietveld refinement,electron paramagnetic resonance spectroscopy,and in the photoluminescence spectra.The color-tunable emissions included the white light that originated from the combination of the blue emission of Sr_(5)(PO_(4))_(3)Cl:Eu^(2+) and an induced Eu^(2+) yellow emission at approximately 550 nm in the solid solution.Importantly,the white-light phosphors showed a greater R9590.2 under excitation at 365 nm.This result has rarely been reported in the literature and is greater than that of(R9514.3)commercial Y_(3)A_(l5)O_(12):Ce^(3+)-based WLEDs.These findings demonstrate the great potential of Sr_(5)(PO_(4))_(3-x)(BO_(3))_(x)Cl:0.04Eu^(2+) as a white-light phosphor for near-UV phosphor-converted WLEDs.These results also provide a shortcut for developing a high CRI white-light phosphor from a single Eu^(2+)-doped compound.Peng-Peng Dai Cong Li Xin-Tong Zhang Jun Xu Xi Chen Xiu-Li Wang Yan Jia Xiaojun Wang Yi-Chun Liu 2016Light(Science & Applications)2016,5,1:14
19Two new diarylheptanoids from the pericarps of Juglans regia L.显示文摘二新周期的 diarylheptanoids juglanin A (1 ) 和 juglanin B (2 ) 从 Juglans regia L 的果皮被孤立。他们的结构被各种各样的分光镜的方法包括 2D NMR 技术阐明(舒适, HMQC, HMBC, NOESY ) 并且 HR-ESIMS。Jun Xi Liu Duo Long Di Xin Yi Huang Chen Li 2007Chinese Chemical Letters2007,18,8:14
20Synthesis and Characterization of Phosphated Konjac Glucomannan Hydrogels显示文摘Konjac glucomannan (KGM) was crosslinked with sodium tripolyphosphate (STPP) to synthesize hydrogels. The crosslinking reaction was confirmed by FT-IR. The results of degradation test show that the hydrogels retain the enzymatic degradation character of KGM and can be degraded for 74.45% in 5 days by cellulase E0240.Li Gui CHEN Zhi Lan LIU Ying Jun CHEN Ren Xi ZHUO 2005Chinese Chemical Letters2005,16,12:13
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