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Identification of winter long-lasting regional extreme low-temperature events in Eurasia and their variation during 1948—2017

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Advances in Climate Change Research 2021年第3期12卷 353-362页

作者： ZHANG Ying-Xian liu yan-ju DING Yi-Hui Laboratory for Climate Studies National Climate CenterChina Meteorological AdministrationBeijing100081China

Compared with short-duration events,long-lasting regional extreme low-temperature events(RELTEs)often have more severe impacts on human societies due to the induced persistence and large geographic area of related weather and climate ***,an improved objective technique was applied to identify all long-lasting RELTEs in Eurasia from the winter of 1948/1949 to 2017/2018,followed by an in-depth discussion of its variation in terms of the annual frequency,duration,impacted area,mean intensity,maximum intensity,and a comprehensive *** RELTE lasting for 52 d in the winter of 2007/2008 exhibited the longest duration,largest impacted area,and a greatest comprehensive index,which induced extremely low temperatures for more than 20 d in Western Asia,Central Asia,and *** the past 70 winters,the frequency of long-lasting RELTEs decreased,especially after the late ***,the mean and maximum intensities and comprehensive index exhibited distinctly increasing *** indicators of winter long-lasting RELTEs had a similar inter-decadal fluctuation featured by two noticeable peaks occurring around 1970 and 2007,and a remarkable recovery was discovered in the period of late 1990s to mid-2010s,especially for the occurrence of super long-lasting ***,winter long-lasting RELTEs in Eurasia showed distinct trends under various decadal climate backgrounds,i.e.,a strong negative or weak positive trend in the accelerated warming period and conversely,a strong positive or weak negative trend in the wanning slowdown *** findings indicate that we should be alert of the similar future recovery of winter long-lasting RELTEs in Eurasia,which are likely to occur in the slowdown period of global warming.

关键词： Regional extreme low-temperature events Winter Long-lasting Eurasia Climate variation

The Influence of Climate Change on Winter Wheat during 2012-2100 under A2 and A1B Scenarios in China

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Advances in Climate Change Research 2012年第3期3卷 138-146页

作者： SONG yan-Ling CHEN De-Liang liu yan-ju XU Ying National Climate Centre China Meteorological AdministrationBeijing 100081China Department of Earth Sciences University of GothenburgGothenburg Box 460Sweden

By assuming constant winter wheat varieties and agricultural practices in China, the influence of climate change on winter wheat is simulated using the corrected future climate projections under SRES A2 and A1B scenarios from 2012 to 2100, respectively. The results indicate that the growth of winter wheat would be strongly influenced by climate change in future. The average flowering and maturity dates of winter wheat would advance by 26 and 27 days under scenario A2, and by 23 and 24 days respectively under scenario A1B from 2012 to 2100. The simulated potential productivity of winter wheat shows a decrease of 14.3% and 12.5% for scenarios A2 and A1B respectively without the fertilization effect of CO2, while an increase of 1.3% and 0.6% with the fertilization effect of CO2. Additionally, for northern China, the simulated potential productivity would markedly decrease under both scenarios, independent with the fertilization effect of CO2, which indicates that the current planted winter wheat would be more vulnerable than that in southern China. The most likely reason is the current winter wheat varieties in northern China are winter varieties or strong winter varieties, which need some days of low temperature for dormancy. While in southern China, the winter wheat is spring or half winter varieties and can grow slowly during winter, thus, they would be affected slightly when winter temperature increases. The results of this study may have important implications for adaptation measures.

关键词： climate change A2 and A1B scenarios WOFOST winter wheat China

Primary obturator foramen pregnancy： a case report and review of literature

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Chinese Medical Journal 2008年第14期121卷 1328-1330页

作者： LIN Jing-xian liu Qi ju yan GUAN Qun WU Yuan-zhe ZHENG Ning Department of Obstetrics and Gynecology Nanjing Jinling Hospital Nanjing Jiangsu 210002 China

Ectopic pregnancy, in which the fertilized ovum implants on any tissue other than the endometrium, is the most common life-threatening emergency in the first trimester of pregnancy. The incidence of ectopic pregnancy is 0.25%-1.0% of all pregnancies, and has increased greatly in the last few decades, from 4.5 per 1000 pregnancies in 1970 to an estimated 19.7 per 1000 pregnancies in 1992.^1

关键词： ectopic pregnancy obturator foramen pregnancy laparotomy laparoscopy

Synthesis,structure,and luminescence properties of melilite Dy^(3+):Lu_(x)CaLa_(0.98-x)Ga_(3)O_(7) phosphors for use in yellow light-emitting devices

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Journal of Rare Earths 2024年第8期42卷 1489-1495,I0003页

作者： Yunyun liu Chuanxin Huang Meng Wang Xihu Wang yan Wang ju Gao School of Opto-Electronic Engineering Zaozhuang UniversityZaozhuang277160China Key Laboratory of Functional Materials and Devices for Informatics of Anhui Educational Institutions Department of PhysicsFuyang Normal UniversityFuyang236037China Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002.China

Dy^(3+) and Lu^(3+) co-doped CaLaGa_(3)O_(7) phosphors were prepared via high-temperature solid-phase *** electronic structures of LuxCaLa_(0.98-x)Ga_(3)O_(7) were investigated by the first-principles *** influence of Lu^(3+) on yellow light emission was studied using X-ray diffraction(XRD)and photoluminescence(PL) *** XRD results indicate that compared to Dy^(3+):CaLaGa_(3)O_(7),the cell parameters of Dy^(3+):LuCaLaGa_(3)O_(7) tend to decrease,which is due to the smaller radius of Lu^(3+).When pumped by blue GaN laser diode(LD),the emission peaks of phosphors with different Lu^(3+)doping concentrations in the visible region are similar,with the strongest peak at 574 nm in the yellow light region,which is sensitive to human *** optimal doping concentration of Lu^(3+) is confirmed to be1 at%,when all emission spectra and measured fluorescence lifetimes are taken into ***,the optimal phosphor composition Dy^(3+):Lu_(x)CaLa_(0.98-x)Ga_(3)O_(7)(x=0.01) has an internal quantum efficiency(IQE) of 46.94% and an external quantum efficiency(EQE) of 15.19%.Most notably,the prepared phosphor demonstrates excellent thermal stability and a high activation energy(0.203 eV).In addition,the International Illumination Commission color coordinates of the Dy^(3+):LuxCaLa_(0.98-x)Ga_(3)O_(7) phosphors are in the yellow light *** above analysis indicates that the Dy^(3+):LuxCaLa_(0.98-x)Ga_(3)O_(7)(x=0.001)phosphor has promising application prospects in yellow light-emitting devices.

关键词： Dy^(3+):Lu_(x)CaLa_(0.98-x)Ga_(3)O_(7)phosphors Yellow emission Structure characteristics Luminescent properties Rare earths

Finite Element Method Simulation of Wellbore Stability under Different Operating and Geomechanical Conditions

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Fluid Dynamics & Materials Processing 2024年第1期20卷 205-218页

作者： junyan liu ju liu yan Wang Shuang liu Qiao Wang Yihe Du Oil&Gas Project Research Institute PetroChina Tarim Oilfield CompanyKorla841000China Petroleum Engineering School Southwest Petroleum UniversityChengdu610500China

The variation of the principal stress of formations with the working and geo-mechanical conditions can trigger wellbore instabilities and adversely affect the well completion.A finite element model,based on the theory of poro-elasticity and the Mohr-Coulomb rock damage criterion,is used here to analyze such a *** changes in wellbore stability before and after reservoir acidification are simulated for different pressure *** results indicate that the risk of wellbore instability grows with an increase in the production-pressure difference regardless of whether acidification is completed or not;the same is true for the instability *** acidizing,the changes in the main geomechanical parameters(i.e.,elastic modulus,Poisson’s ratio,and rock strength)cause the maximum wellbore instability coefficient to increase.

关键词： Wellbore stability finite element acidizing operation well completion

Composition optimization and performance prediction for ultra-stable water-based aerosol based on thermodynamic entropy theory

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Defence Technology（防务技术） 2024年第3期33卷 437-446页

作者： Tingting Kang Canjun yan Xinying Zhao Jingru Zhao Zixin liu Chenggong ju Xinyue Zhang Yun Zhang yan Wu College of Chemical Engineering and Materials Science Tianjin University of Science and TechnologyNo.29 13th AvenueEconomic and Technologic Development ZoneTianjin 300457China Tianjin Key Laboratory of Brine Chemical Engineering and Resource Eco-utilization Tianjin University of Science and TechnologyTianjin 300457China College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China

Water-based aerosol is widely used as an effective strategy in electro-optical countermeasure on the battlefield used to the preponderance of high efficiency,low cost and ***,the stability of the water-based aerosol is always unsatisfactory due to the rapid evaporation and sedimentation of the aerosol *** efforts have been devoted to improve the stability of water-based aerosol by using additives with different composition and ***,the lack of the criterion and principle for screening the effective additives results in excessive experimental time consumption and *** the stabilization time of the aerosol is still only 30 min,which could not meet the requirements of the perdurable ***,to improve the stability of water-based aerosol and optimize the complex formulation efficiently,a theoretical calculation method based on thermodynamic entropy theory is *** the factors that influence the shielding effect,including polyol,stabilizer,propellant,water and cosolvent,are considered within *** ultra-stable water-based aerosol with long duration over 120 min is obtained with the optimal fogging agent composition,providing enough time for fighting the electro-optic *** design guideline for choosing the additives with high phase transition temperature and low phase transition enthalpy is also proposed,which greatly improves the total entropy change and reduce the absolute entropy change of the aerosol cooling process,and gives rise to an enhanced stability of the water-based *** theoretical calculation methodology contributes to an abstemious time and space for sieving the water-based aerosol with desirable performance and stability,and provides the powerful guarantee to the homeland security.

关键词： Ultra-stable Water-based aerosol Thermodynamic entropy Composition optimization Performance prediction

ROLE OF A WARM AND WET TRANSPORT CONVEYOR OF ASIAN SUMMER MONSOON IN A BEIJING HEAVY RAINSTORM ON juLY 21,2012

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Journal of Tropical Meteorology 2017年第3期23卷 302-313页

作者： liu yan-ju DING Yi-hui ZHANG Ying-xian SONG Ya-fang National Climate Center China Meteorological Administration Beijing 100081 China

A heavy rainstorm named Beijing "7.21"heavy rainstorm hit Beijing on 21 to 22 july 2012, which is recorded as the most severe rainstorm since 1951. The daily precipitation amount in many stations in Beijing has broken the history record. Based on the NCAR/NCEP reanalysis data and precipitation observation,the large-scale conditions which caused the "7.21"heavy rainstorm are investigated, with the emphasis on the relationship between it and an equatorial convergence zone, Asian summer monsoon as well as the tropical cyclone over the ocean from the Philippines to the South China Sea(SCS). The results indicated that a great deal of southerly warm and wet moisture carried by northward migrating Asian summer monsoon provided plenty of moisture supplying for the "7.21"heavy rainstorm. When the warm and wet moisture met with the strong cold temperature advection induced by cold troughs or vortexes, an obviously unstable stratification formed, thus leading to the occurrence of heavy precipitation. Without this kind of intense moisture transport, the rainstorm only relying on the role of the cold air from mid-and higher-latitudes could not reach the record-breaking intensity. Further research suggested that the northward movement of an Asian monsoonal warm and wet moisture transport conveyor(MWWTC) was closely related with the active phase of a 30-60 day intra-seasonal oscillation of the Asian summer monsoon. During this time, the monsoon surge triggered and maintained the northward movement of the MWWTC. In addition, compared with another heavy rainstorm named"63.8"heavy rainstorm, which occurred over the Huaihe River Basin in the mid-August 1963 and seriously affected North China, a similar MWWTC was also observed. It was just the intense interaction of the MWWTC with strong cold air from the north that caused this severe rainstorm.

关键词： Beijing "7.1" heavy rainstorm Asian summer monsoon warm and wet transport conveyor

Gut microbiota-derived short-chain fatty acids and depression:deep insight into biological mechanisms and potential

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General Psychiatry 2024年第1期37卷 17-32页

作者： junzhe Cheng Hongkun Hu Yumeng ju Jin liu Mi Wang Bangshan liu yan Zhang Department of Psychiatry National Clinical Research Center for Mental DisordersSecond Xiangya Hospital of Central South UniversityChangshaHunanChina Clinical Medicine Eight-Year Program Xiangya School of MedicineCentral South UniversityChangshaHunanChina Mental Health Institute of Central South University China National Technology Institute on Mental DisordersHunan Key Laboratory of Psychiatry and Mental HealthHunan Medical Center for Mental HealthChangshaHunanChina Department of Mental Health Center Xiangya Hospital of Central South UniversityChangshaHunanChina

The gut microbiota is a complex and dynamic ecosystem known as the second brain'.Composing the microbiota-gut-brain axis,the gut microbiota and its metabolites regulate the central nervous system through neural,endocrine and immune pathways to ensure the normal functioning of the organism,tuning individuals'health and disease ***-chain fatty acids(SCFAs),the main bioactive metabolites of the gut microbiota,are involved in several neuropsychiatric disorders,including *** have essential effects on each component of the microbiota-gut-brain axis in *** the present review,the roles of major SCFAs(acetate,propionate and butyrate)in the pathophysiology of depression are summarised with respect to chronic cerebral hypoperfusion,neuroinflammation,host epigenome and neuroendocrine *** remarks on the biological mechanisms related to gut microbiota will hopefully address the clinical value of microbiota-related treatments for depression.

关键词： alterations inflammation perfusion

“酒制升提”炮制理论在“寒性”中药中的应用及研究进展

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湖北中医药大学学报 2024年第4期26卷 120-124页

作者：陈高源韩一凡韩羽亭谢颖颜春潮涂济源刘艳菊湖北中医药大学湖北武汉430065 湖北省中药炮制工程技术研究中心湖北武汉430065

酒制可引药上行、增效减毒、缓解寒性中药过偏之性产生的副作用。“酒制升提”指导着中药药性理论的研究和“寒性”中药的炮制与临床应用。本文研究酒制对寒性中药的物质基础、药理药效、作用机制等的作用,揭示“酒制升提”炮制理论的... 详细信息

酒制可引药上行、增效减毒、缓解寒性中药过偏之性产生的副作用。“酒制升提”指导着中药药性理论的研究和“寒性”中药的炮制与临床应用。本文研究酒制对寒性中药的物质基础、药理药效、作用机制等的作用,揭示“酒制升提”炮制理论的发生发展与科学内涵,为深度挖掘“酒制升提”炮制理论的现实研究与应用提供参考与思路。

关键词：中药寒性酒制升提炮制理论