检索结果-南通市图书馆

Variations of Winter Precipitation over Southeastern China in Association with the North Atlantic Oscillation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Meteorological Research 2017年第3期31卷 476-489页

作者： Maoyuan LOU Chao li Shifeng HAO juan liu Zhejiang Provincial Meteorological Observatory Zhejiang Institute of Meteorological Sciences Zhejiang Meteorological Service Center

The synoptic-scale winter precipitation variations over southeastem China （22°-32°N, 105°-125°E） and their asso- ciation with the North Atlantic Oscillation （NAO） during 1951-2007 are investigated in this paper. The variability of wintertime precipitation is characterized by meridional displacement of its maximum center. Two precipitation re- gimes, with maximum centers located over the Yangtze and Pearl River basins, are identified via cluster analysis. Time-lagged analyses suggest that the two precipitation regimes are connected with the decaying phases of positive NAO （NAO＋） events of different amplitudes. A strong （medium） NAO＋ event is defined as one when the maximum amplitude of the NAO index exceeds 1.0 （in the range of 0.7-1.0） for at least 4 consecutive days and drops to less than 0.3 within 7 days following the peak index. After the peak of a strong NAO＋, southerly winds expand north- ward to the Yangtze River （about 30°N）, a northeast-southwest-tilted trough migrates to east of Lake Baikal, and cold air intrudes into central eastern China; thus, precipitation is strengthened over the Yangtze River basin where warm and cold air masses converge. In comparison, during the decaying phase of medium NAO＋ events, the south- erly winds are relatively weak, and precipitation tends to be enhanced at lower latitudes （around 25°N）. Further ana- lysis indicates that downstream Rossby-wave propagation may account for the latitudinal expansion of the southerly wind anomalies over the eastern coastal area of China during the decaying phase of NAO＋ events of different strengths.

关键词： precipitation regime North Atlantic Oscillation (NA0) cluster analysis westerly jet stream

Temperature-induced dissociation reaction and dynamics of light-harvesting complex II isolated from purple photosynthetic bacterium ***

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2007年第8期52卷 1029-1035页

作者： FENG juan li XueFeng liu Yuan School of life Science and Technology University of Electronic Science & Technology of China Chengdu 610054 China

Steady-state absorption spectroscopy,circular dichroism,and resonance Raman spectroscopy have been used to investigate the thermal stability of LH2 complex isolated from purple photosynthetic bacterium *** results show that:1)upon increasing the temperature,a transition from B800 and B850 to free bacteriochlorophyll(B780)happens;2)a gradual decrease and disappearance of CD signal in visible region occur;3)a shift of the frequency,belonging to C==C and C—C stretching vibration,to higher wavenumber takes *** is suggested that LH2 complex can be dissociated in the presence of B800,B850 and carotenoids ***-exponential fitting on the dynamic decay curves gives the apparent time constants of hundreds of minutes for various pigments.

关键词：紫色光合细菌沼泽红假单胞菌温度诱导离解反应反应动力学捕光配合物Ⅱ

Flame behavior, shock wave, and instantaneous thermal field generated by unconfined vapor-liquid propylene oxide/air cloud detonation

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2023年第7期25卷 18-32页

作者： Cong-liang Ye Qing-lei Du li-juan liu Qi Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China School of Safety Science and Emergency Management Wuhan University of TechnologyWuhanHubei430070China

Energy output and heating effects are essential for vapor-liquid fuel/air cloud detonation in the fuel-air explosive(FAE) applications or explosion accidents. The purpose of this study is to examine the dynamic large-size flame behavior, shock wave propagation law, and instantaneous thermal field generated by unconfined vapor-liquid propylene oxide(PO)/air cloud detonation. Based on computational fluid dynamics(CFD) and combustion theory, a numerical simulation is used to study the detonation process of a PO/air cloud produced by a double-event fuel-air explosive(DEFAE) of 2.16 kg. The large-scale flame behavior is characterized. The flame initially spreads radially and laterally in a wing shape. Subsequently,the developed flame increases with a larger aspect ratio. Moreover, the propagation laws of shock waves at different heights are discussed. The peak pressure of 1.3 m height level with a stepwise decline is obviously different from that of the ground with an amplitude of reversed ’N’ shape. In the vast majority of the first 6.9 m, the destructive effect of the shock wave near the ground is greater than that of the shock wave at 1.3 m height. Furthermore, the dynamic instantaneous isothermal field is *** scaling relationship of various isotherms in the instantaneous thermal field with the flame and initial cloud is summarized. The comprehensive numerical model used in this study can be applied to determine the overpressure and temperature distribution in the entire fuel/air cloud detonation field,providing guidance for assessing the extent of damage caused by DEFAE detonation.

关键词： Numerical simulation Fuel-air explosive Fuel/air cloud Flame Shock wave Thermal field

Determination of diastereoisomeric alkaloids in urine by capillary electrophoresis with electrochemiluminescence detection

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第2期22卷 197-200页

作者： Yan Ming liu Long Fei Peng lin Mei li juan liu College of Chemistry and Chemical Engineering Xinyang Normal University Xinyang 464000 China Received 1 July 2010

A new and simple capillary electrophoresis with electrochemiluminescence detection was developed for the separation and the quantification of a pair of diastereoisomenc alkaloids（ephedrine and pseudoephedrine）.The limits of detection（S/N = 3） were 4.5×10^-8 mol/L for ephedrine and 5.2×10^-8 mol/L for pseudoephedrine,*** RSDs of migration time and peak area were less than 1.3 and 2.5%（n = 5）,*** applicability of the propose method was illustrated in the determination of ephedrine and pseudoephedrine in human urine,ephedrine in nasal drops,and the monitoring of pharmacokinetics for pseudoephedrine.

关键词： CE Electrochemiluminescence Alkaloids Urine analysis Pharmacokinetics

Exosomes as potential diagnosis and treatment for liver cancer

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2022年第1期14卷 334-347页

作者： Xiao-Cui Wei li-juan liu Fan Zhu State Key Laboratory of Virology Hubei Province Key Laboratory of Allergy and ImmunologyDepartment of Pathogenic BiologySchool of MedicineWuhan UniversityWuhan 430071Hubei ProvinceChina

BACKGROUND liver cancer is the fourth most significant cause of cancer-related *** of early diagnosis strategy and a scarcity of efficient therapy constitute the main reasons for its ***,which contain various bioactive molecules,are characterized by high biocompatibility,low immunogenicity,and high transport *** a result,exosomes have become a research hotspot and present significant potential for cancer diagnosis biomarkers,biotherapeutics,therapy targets,drug carriers and therapeutic *** To explore the potential of exosomes in the diagnosis and treatment of liver *** We conducted a systematic literature search via PubMed and Web of *** following keywords were used:"exosomal biomarkers","exosomal therapy","exosomal therapy",and"liver cancer"or"HCC".The duplicate data were deleted by EndNote *** search focused on full-texts and references of each article were carefully *** author(Xiao-Cui Wei)screened the literature that met the following inclusion criteria:(1)Detection of exosomes or their contents in clinical samples(body fluid or tissue);or(2)Exosomes served as drug carriers or therapeutic *** authors(Xiao-Cui Wei and li-juan liu)independently reviewed all retained literature and analyzed the *** A total of 1295 studies were identified using the systematic literature *** these,835 duplicate studies were removed.A further 402 irrelevant studies were excluded due to being irrelevant,including other diseases,review articles,the literature containing neither clinical samples nor animal experiments,exosomeindependent studies,methods for detecting exosomes,or articles in ***,58 published papers were retained and analyzed in the *** showed a list of potential exosomal biomarkers that were upregulated in the blood samples of patients with liver *** downregulated in exosomes might serve as possible *** exosomes derived

关键词： Exosomes liver cancer Biomarker Treatment Drug delivery system

Proliferating cell nuclear antigen clamp associated factor,a potential proto-oncogene with increased expression in malignant gastrointestinal tumors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2021年第10期13卷 1425-1439页

作者： li-juan liu Jian-Ming liao Fan Zhu State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy&Immunology Department of Medical MicrobiologySchool of MedicineWuhan UniversityWuhan 430071Hubei ProvinceChina Department of Neurosurgery Renmin HospitalWuhan UniversityWuhan 430060Hubei ProvinceChina

Gastrointestinal(GI)cancers,including malignancies in the gastrointestinal tract and accessory organs of digestion,represent the leading cause of death worldwide due to the poor prognosis of most GI *** investigation into the potential molecular targets of prediction,diagnosis,prognosis,and therapy in GI cancers is urgently *** cell nuclear antigen(PCNA)clamp associated factor(PCLAF),which plays an essential role in cell proliferation,apoptosis,and cell cycle regulation by binding to PCNA,is a potential molecular target of GI cancers as it contributes to a series of malignant properties,including tumorigenesis,epithelial-mesenchymal transition,migration,and ***,PCLAF is an underlying plasma prediction target in colorectal cancer and liver *** addition to GI cancers,PCLAF is also involved in other types of cancers and autoimmune *** pivotal pathways,including the Rb/E2F pathway,NF-κB pathway,and p53-p21 cascade,are implicated in PCLAF-mediated *** also contributes to some diseases through dysregulation of the p53 pathway,WNT signal pathway,MEK/ERK pathway,and PI3K/AKT/mTOR signal *** review mainly describes in detail the role of PCLAF in physiological status and GI *** signaling pathways involved in PCLAF are also *** of the interaction of PCLAF/PCNA or the expression of PCLAF might be potential biological therapeutic strategies for GI cancers.

关键词： Proliferating cell nuclear antigen Proliferating cell nuclear antigen clamp associated factor Transcript variant Gastrointestinal cancers Signal pathway Biological therapeutic

Luminescence Regulation of Silver-Thiolate Clusters Protected by 1,2-Dithiolate-o-carborane

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2021年第1期39卷 81-86页

作者： li-juan liu Thomas C.W.Mak Shuang-Quan Zang College of Chemistry Zhengzhou UniversityZhengzhouHenan 450001China Department of Chemistry The Chinese University of Hong KongShatinNew TrritriesHong Kong SARChina

Engineering the surface of the metal clusters with the core structure maintained and tuning their luminescence in a wide range is still a challenge in the nanomaterial *** modified six mono-pyridyl ligands with different electronic effects(conjugation effect or induction effect)on a superatomic silver cluster[Ag_(14)(C_(2)B_(10)H_(10)S_(2))_(6)(CH_(3)CN)_(8)](denoted as Ag_(14))through in situ site-specific surface engineering.

关键词： Silver clusters Surface modification 1,2-Dithiolate-o-carborane Luminescence

Effect of Zn addition on microstructure and mechanical properties of Mg-3Y-2Nd-0.5Zr alloy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Foundry 2023年第4期20卷 299-306页

作者： Fei-yu He Wen-xin Hu li-juan liu Shao-bo Ma Wei He State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou 014030Inner MongoliaChina Baotou Research Institute of Rare Earths Baotou 014030Inner MongoliaChina Technical Center of Steel Union Co. Ltd.of Baotou Steel(Group)Corp.Baotou 014010Inner MongoliaChina

The effect of 0.5wt.%Zn addition on the microstructure and mechanical properties of Mg-3Y-2Nd-0.5Zr(WE32)alloy was *** results indicate that WE32-0.5Zn alloy takes 48 h to reach peak hardness after solid solution treatment at 525℃and aging at 200℃,10 h earlier than WE32 alloy,which implies an accelerated aging precipitation kinetics owing to the addition of 0.5wt.%Zn.A large quantity of finerod and rectangular block-like Zn-Zr precipitates in theα-Mg matrix are formed in the WE32-0.5Zn alloy,and numerous needle-likeβ1phases are distributed at both ends of the Zn-Zr precipitates at peak-aged *** peak-aged condition,the ultimate tensile strength considerably increases from 263.2 MPa(WE32)to 309.6 MPa(WE32-0.5Zn),and the elongation dramatically increases from 4.3%(WE32)to 8.9%(WE32-0.5Zn).Theβ’andβ1phases are the main precipitates of the WE32-0.5Zn alloy peak-aged at 200℃.Theβ’andβ1phases easily nucleate at the Zn-Zr precipitates,and theβ1phases are particularly likely to nucleate and grow at the interface between the two ends of the Zn-Zr precipitates,which accelerates aging precipitation kinetics and leads to a shorter time to achieve peak aging.

关键词： Mg-3Y-2Nd-0.5Zr Zn-Zr precipitates microstructure mechanical properties

Added Benefit of the Early-Morning-Orbit Satellite Fengyun-3E on the Global Microwave Sounding of the Three-Orbit Constellation

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2024年第1期41卷 39-52页

作者： juan li Zhengkun QIN Guiqing liu Jing HUANG CMA Earth System Modeling and Prediction Centre Beijing 100081China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Joint Center for Data Assimilation Research and Applications School of Atmospheric SciencesNanjing University of Information Science&TechnologyNanjing 210044China

The three-orbit constellation can comprehensively increase the spatial coverage of polar-orbiting satellites,but the polar-orbiting satellites currently in operation are only mid-morning-orbit and afternoon-orbit ***-3E(FY-3E)was launched successfully on 5 July 2021 in *** an early-morning-orbit satellite,FY-3E can help form a complete three-orbit observation system together with the mid-morning and afternoon satellites in the current mainstream operational *** this study,we investigate the added benefit of FY-3E microwave sounding observations to the midmorning-orbit Meteorological Operational satellite-B(Met Op-B)and afternoon-orbit Fengyun-3D(FY-3D)microwave observations in the Chinese Meteorological Administration global forecast system(CMA-GFS).The results show that the additional FY-3E microwave temperature sounder-3(MWTS-3)and microwave humidity sounder-2(MWHS-2)data can increase the global coverage of microwave temperature and humidity sounding data by 14.8% and 10.6%,*** enables the CMA-GFS to achieve nearly 100% global coverage of microwave-sounding observations at each analysis ***,after effective quality control and bias correction,the global biases and standard deviations of the differences between observations and model simulations are also *** on the Advanced Microwave Sounding Unit A and the Microwave Humidity Sounder onboard Met Op-B,and the MWTS-2 and MWHS-2 onboard FY-3D,adding the microwave sounding data of FY-3E can further reduce the errors of analysis results and improve the global prediction skills of CMA-GFS,especially for the southern-hemisphere forecasts within 96 hours,all of which are significant at the 95% confidence level.

关键词： data assimilation microwave temperature sounder MWTS-3