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寒性与热性中药对小鼠棕色脂肪组织中产热调节蛋白UCP1基因和蛋白表达的影响
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作者 杨玉娇 王朋倩 +7 位作者 张淼 吴茵 石忠峰 周炜炜 孟晶 霍海如 隋峰 韩亮 《中华中医药杂志》 CAS CSCD 北大核心 2019年第4期1679-1681,共3页
目的:观察寒性与热性中药对机体产热的关键节点解偶联蛋白-1(UCP1)的调节作用,寻找寒热药性的共性的生物学规律。方法:分别采用Real-time RCR和Western blot的方法研究寒性中药(黄连、黄芩、黄柏)和热性中药(白芷、肉桂、胡椒)对小鼠棕... 目的:观察寒性与热性中药对机体产热的关键节点解偶联蛋白-1(UCP1)的调节作用,寻找寒热药性的共性的生物学规律。方法:分别采用Real-time RCR和Western blot的方法研究寒性中药(黄连、黄芩、黄柏)和热性中药(白芷、肉桂、胡椒)对小鼠棕色脂肪组织中UCP1 mRNA和蛋白表达的影响。结果:寒性中药对UCP1 mRNA和蛋白表达均有显著下调作用(P<0.01,P<0.05);热性中药除胡椒外对UCP1 mRNA和蛋白表达均有上调作用(P<0.01)。结论:在基因和蛋白层面调节UCP1表达的生物效应可能是寒性与热性中药的共性特征之一,与中药药性的寒热性表征相关。 展开更多
关键词 寒性 热性 中药 解偶联蛋白 基因 蛋白 寒热性表征
Research status and progress of tunnel frost damage
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作者 Yanbin Luo Jianxun Chen 《交通运输工程学报(英文版)》 CSCD 2019年第3期297-309,共13页
The problems of frost damage in cold region tunnels have been systematically analyzed and studied by local and foreign scholars. A series of important achievements has been proposed. In this paper, the research result... The problems of frost damage in cold region tunnels have been systematically analyzed and studied by local and foreign scholars. A series of important achievements has been proposed. In this paper, the research results on mechanism of frost damage, analysis of temperature field, classification of frost damage levels, and frost prevention technologies are summarized. The principles and limitations of the three major theories of frost damage mechanism are elaborated, and the importance of structural damage research on shotcrete in cold region tunnels is emphasized. Two major defects of current research on temperature field are concluded. The present situation of research on frost damage classification of cold region tunnels is discussed. The directions of further studies for tunnel temperature field and frost damage classification are proposed. The prevention technologies for tunnel frost damage in foreign countries, and the advantages and disadvantages of the four major prevention technologies in China and their applicable conditions, are concluded and analyzed. Meanwhile, the importance of frost damage classification is highlighted. Therefore, the local and foreign research results for cold region tunnels are systematically concluded, the defects of the researches are comprehensively analyzed, and the directions of further study are proposed. They are significant to solve the problems of tunnel frost damage in the future. 展开更多
关键词 COLD region TUNNEL FROST DAMAGE mechanism Temperature field TUNNEL FROST DAMAGE classification Prevention MEASURE
Superfluidity of Deuterons in Metal-Deuterium Solid Solutionsand Cold Fusion 预览
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作者 Afanasev Sergei Borisovich 《物理科学与应用:英文版》 2019年第1期43-48,共6页
It is shown that the formation of a Bose-condensate of delocalized deuterons in solid solutions of metals and deuterium leads to the possibility of a d-d-fusion reaction in which one superfluid deuteron and one deuter... It is shown that the formation of a Bose-condensate of delocalized deuterons in solid solutions of metals and deuterium leads to the possibility of a d-d-fusion reaction in which one superfluid deuteron and one deuteron that does not participate in superfluid motion participate.Overcoming the Coulomb barrier is due to the large kinetic energy of macroscopic superfluid motion.It is shown that the intensity of the nuclear reaction depends on the velocity of the superfluid motion and,as a consequence,on the magnitude of the vector B of the external magnetic field.In the London Electrodynamics approximation,a linear dependence of the power released during the nuclear reaction on the magnitude of the vector B of the external magnetic field is obtained. 展开更多
关键词 SUPERFLUIDITY DEUTERON cold FUSION energy release magnetic field
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Effect of Prior Cold Deformation on the Stability of Retained Austenite in GCr15 Bearing Steel
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作者 Feng Wang Dong-Sheng Qian Xiao-Hui Lu 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第1期107-115,共9页
In this work, the effect of prior cold deformation on the stability of retained austenite in GCr15 bearing steel was investigated after quenching and tempering treatment. The thermal stability was evaluated by calcula... In this work, the effect of prior cold deformation on the stability of retained austenite in GCr15 bearing steel was investigated after quenching and tempering treatment. The thermal stability was evaluated by calculating thermal activation energy for decomposition of retained austenite using differential scanning calorimeter. The mechanical stability was investigated according to the strain-induced martensitic transformation behavior of retained austenite under the standard compression testing. It is found that the prior cold deformation not only accelerates the carbide dissolution during the austenitization process but also contributes to the carbon partitioning in the tempering stage due to the higher density of phase boundaries, which results in the improvement of the thermal stability of retained austenite. Due to the enhanced carbide dissolution, the higher carbon content in the prior austenite will intensify the isotropic strain of martensitic transformation. As a consequence, the film-like retained austenite is likely to form under a higher hydrostatic pressure and thus shows a higher mechanical stability. Additionally, it is noteworthy that the benefits of the prior cold deformation to the stability of retained austenite would be saturated when the cold deformation degree is larger than 40%. 展开更多
关键词 GCR15 BEARING steel Prior cold deformation RETAINED AUSTENITE stability
1960–2016年中国北方寒潮事件时空变化分析(英文)
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作者 高文兰 段克勤 李双双 《地理学报:英文版》 SCIE CSCD 2019年第6期971-983,共13页
Among the most devastating extreme weather events, cold surge(CS) events frequently impact northern China. It has been reported that extreme weather events will increase in the global warming context. However, the dir... Among the most devastating extreme weather events, cold surge(CS) events frequently impact northern China. It has been reported that extreme weather events will increase in the global warming context. However, the direct evidence of this hypothesis is limited. Here, we investigated the changes in frequency, number, duration, and temperature of CS events in northern China using the daily minimum temperature dataset of 331 stations from 1960 to 2016. The results indicate that the annual CS events in terms of frequency and number decreased, and the duration shortened as the starting date was later and the ending date earlier. Meanwhile, the annual CS temperature increased. In addition, spatial trends in the CS events in terms of frequency, number, and duration decreased while the CS temperature increased in most regions of northern China. We interpreted these variations as a response to global warming. However, the extreme CS events in terms of frequency, number and the earliest starting date and the latest ending date showed little change though the extreme CS temperature increased, implying climate warming had not limited extreme CS events. The adverse effect of CS events on agriculture and human health remain concerning. 展开更多
关键词 cold SURGE frequency NUMBER DURATION temperature NORTHERN China
Research on Optimizing the Distribution Path of Agricultural Cold Chain Logistics in Green Consumption Era 预览
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作者 Li Zhang 《电子商务学刊:中英文版》 2019年第1期13-17,共5页
In recent years, with the rapid development of China's fresh market, cold chain logistics ushered in a new development opportunity. Because of the late start and slow development of cold chain logistics in China, ... In recent years, with the rapid development of China's fresh market, cold chain logistics ushered in a new development opportunity. Because of the late start and slow development of cold chain logistics in China, it is difficult to achieve cross-regional and offseason sales activities, resulting in a situation of high output and small sales volume, which is also an important reason for the high price and poor quality of fresh agricultural products. With the passage of time, the characteristics of cold chain distribution of agricultural products have become an important direction for the future development of logistics industry. In this paper, aiming at the characteristics of agricultural cold chain distribution, the carbon emissions in the process of distribution were quantified as costs and added to the total cost, and an optimization model of agricultural cold chain logistics path with time window considering the minimum total cost as the objective function was constructed. The improved genetic algorithm was used to solve the problem. The simulation results show that the improved genetic algorithm is an effective method to solve the optimization problem of agricultural cold-chain logistics path considering carbon emissions, and has guiding significance for the selection of low-carbon and environmentally friendly distribution routes for agricultural cold-chain logistics distribution enterprises. 展开更多
关键词 Cold CHAIN LOGISTICS FRESH AGRICULTURAL Products Distribution ROUTE Optimization COST-SAVING Method
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Development of the integrated integrating sphere cold atom clock
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作者 于明圆 孟艳玲 +6 位作者 叶美凤 王鑫 欧阳鑫川 万金银 肖玲 成华东 刘亮 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第7期184-187,共4页
We develop an integrated integrating sphere cold atom clock(ISCAC), which mainly consists of physical package,laser system, microwave source, and electronics.This compact system is more stable and reliable than the pr... We develop an integrated integrating sphere cold atom clock(ISCAC), which mainly consists of physical package,laser system, microwave source, and electronics.This compact system is more stable and reliable than the previous version.The experimental results show that the short term frequency stability of 5.4×10^-13τ-1/2 and 2.9× 10^-15 at 1-day integrating time are achieved. 展开更多
关键词 integrating SPHERE COLD ATOM CLOCK physical PACKAGE laser system FREQUENCY stability
Changes in the population structure of Calanus sinicus during summer–autumn in the southern Yellow Sea 预览
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作者 Yongqiang Shi Song Sun +3 位作者 Chaolun Li Guangtao Zhang Bo Yang Peng Ji 《海洋学报:英文版》 SCIE CAS CSCD 2019年第8期56-63,共8页
Calanus sinicus is a calanoid copepod widely distributed in coastal waters of China and Japan, and oversummering strategies may have major impacts on their population dynamics which in turn affect local marine food we... Calanus sinicus is a calanoid copepod widely distributed in coastal waters of China and Japan, and oversummering strategies may have major impacts on their population dynamics which in turn affect local marine food web structure. The abundance, stage composition, and sex composition of the planktonic copepod C. sinicus were studied from August to October 2002 in the southern Yellow Sea to understand how its population recovers from the over-summering state. Results showed that C. sinicus had low reproduction in August due to high temperature, except in waters near the Cheju Island with rich food and moderate bottom temperature, but the reproduction rates here decreased in September–October as food availability declined. When temperature dropped in September–October, C. sinicus actively propagated in coastal shallow waters. However, reproduction rates of C. sinicus individuals inhabiting the Yellow Sea Cold Water Mass(YSCWM) remained low during the three months of the study. The percentage of C. sinicus females was high during the reproductive period, which suggests that the sex composition of adult C. sinicus may reflect whether or not the population is in the reproductive mode.Numerous fifth copepodite stage(CV) C. sinicus aggregated in the YSCWM in a suspended developmental stage during the three months of this study, and they potentially served as the parental individuals for population development when conditions became optimal for reproduction later in the year. 展开更多
关键词 CALANUS SINICUS stage COMPOSITION SEX COMPOSITION population structure YELLOW Sea Cold Water Mass life history strategy
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Achieving strength-ductility synergy in cold spray additively manufactured Al/B4C composites through a hybrid post-deposition treatment
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作者 Naeem ul Haq Tariq Lawrence Gyansah +6 位作者 Xiang Qiu Chunnijia Hasan Bin Awais Chengwu Zheng Hao Du Jiqiang Wang Tianying Xiong 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第6期1053-1063,共11页
Cold spray additive manufacturing(CSAM) provides a potential solid state manufacturing route to fabricate variety of aluminum matrix composites(AMCs) with reduced possibility of undesired chemical reactions and residu... Cold spray additive manufacturing(CSAM) provides a potential solid state manufacturing route to fabricate variety of aluminum matrix composites(AMCs) with reduced possibility of undesired chemical reactions and residual thermal stresses. This study presents a hybrid(i.e. hot compression + hot rolling)post-deposition treatment to reinvigorate the mechanical properties of cold spray additively manufactured Al/B4 C composites. The as-deposited samples were initially subjected to 30% thickness reduction via hot compression treatment at 500°C followed by a hot rolling treatment with 40% thickness reduction in 2 passes. Electron backscatter diffraction(EBSD) and high resolution transmission electron microscopy(HRTEM) results revealed that after hybrid post-deposition treatment(involving 70%accumulative thickness reduction), the aluminum grains in the matrix were extensively refined due to simultaneous operation of continuous dynamic recrystallization(CDRX) and geometric dynamic recrystallization(GDRX). Furthermore, interfacial defects were remarkably reduced while the nature of Al/Al and Al/B4C interfacial bonding was changed from sheer mechanical interlocking to metallurgical bonding which facilitated efficient transference of applied load to uniformly dispersed bimodal B4C particles. As a result, ultimate tensile strength(UTS) and elongation(EL) of the as-deposited sample were simultaneously improved from 37 to 185 MPa and 0.3% to 6.2%, respectively. 展开更多
关键词 Cold spray additive manufacturing Post-deposition treatments Al/B4C COMPOSITES Dynamic recrystallization Mechanical properties
趣味英语听力 预览
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《疯狂英语:初中版》 2019年第4期17-18,共2页
Tomb Sweeping Day,or Qingming Festival in Chinese,is a festival to 1]worship ancestors and deceased relatives in China.It usually falls on 1 Tomb Sweeping Da y can be traced back to Eastern Zhou Dynasty(770BC—256BC),... Tomb Sweeping Day,or Qingming Festival in Chinese,is a festival to 1]worship ancestors and deceased relatives in China.It usually falls on 1 Tomb Sweeping Da y can be traced back to Eastern Zhou Dynasty(770BC—256BC),with 2 over 2500 years.According to the tradition,people 3 during this festival. 展开更多
关键词 QINGMING FESTIVAL TOMB SWEEPING DAY cold FOOD FESTIVAL
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Participation in the absolute gravity comparison with a compact cold atom gravimeter
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作者 付志杰 王启宇 +3 位作者 王兆英 吴彬 程冰 林强 《中国光学快报:英文版》 SCIE EI CAS CSCD 2019年第1期52-57,共6页
The first Asia-Pacific Comparison of Absolute Gravimeters(APMP.M.G-K1) was organized by the National Institute of Metrology(NIM) of China from December 21, 2015 to March 25, 2016 in Changping, Beijing. Our compact col... The first Asia-Pacific Comparison of Absolute Gravimeters(APMP.M.G-K1) was organized by the National Institute of Metrology(NIM) of China from December 21, 2015 to March 25, 2016 in Changping, Beijing. Our compact cold atom gravimeter(CCAG) was transported from Hangzhou to Beijing with a long distance of about1200 km to participate in this comparison. The CCAG is the only one, to the best of our knowledge, that is based on the principle of atom interferometry among all the instruments. Absolute gravity in the indicated three test sites has been measured as requested by the organizer. The sensitivity of our CCAG is estimated to be90 μGal∕Hz p, even when the measurements are carried out without any vibration isolation. Besides, the accuracy of this gravimeter has been evaluated to be about 19 μGal by considering the significant system errors.Our results show a good agreement with the given reference value. 展开更多
关键词 PARTICIPATION ABSOLUTE gravity COMPARISON COMPACT cold ATOM GRAVIMETER
全文增补中
Effect of Compound Treatment with Prochloraz and Chitosan on the Physicochemical Indexes of Refrigerated Citrus Gonggan 预览
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作者 Dongdi XIE Dingli LU 《农业生物技术:英文版》 CAS 2019年第3期98-101,共4页
[Objectives]This study was conducted to investigate the synergized preservation effect of different concentrations of prochloraz and chitosan on citrus Gonggan,so as to prolong the sales period of Gonggan.[Methods]&qu... [Objectives]This study was conducted to investigate the synergized preservation effect of different concentrations of prochloraz and chitosan on citrus Gonggan,so as to prolong the sales period of Gonggan.[Methods]"Zhongshan Gonggan" was used as a material.The Gonggan fruit was soaked with prochloraz (250,300 and 350 mg/L) and then coated with different concentrations of chitosan (1.0% and 1.5%),respectively.The good fruit rate,weight loss rate and titratable acid (TA),reducing sugar,total soluble solids (TSS) and Vc contents were used as evaluation indexes to investigate the preservation effect of Gonggan during cold storage.[Results]The treatment of prochloraz plus chitosan can significantly prolong the shelf life of Gonggan as it can inhibit the decline of good fruit rate,reduce the weight loss rate,and slow down the degradation and loss of titratable acid,reducing sugar,soluble solids and Vc.The 350 mg/L prochloraz+1.0% chitosan treatment was superior to other treatments.[Conclusions]This study provides a theoretical basis for better prolonging the storage period of Gonggan. 展开更多
关键词 ZHONGSHAN Gonggan CHITOSAN PROCHLORAZ Cold storage PHYSICOCHEMICAL indexes
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现代湘语中的三个六朝江东方言词
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作者 吴瑞文 《湖南科技大学学报:社会科学版》 CSSCI 北大核心 2019年第3期130-138,共9页
现代湘语语料显示,从历史词汇的观点而言湘语有一个层次来自六朝江东方言。有三个口语词汇可以证明上述推论:"渹"(凊)、"鼎"(铛)以及"侬"。"渹"(凊)、"鼎"(铛)出现于南朝宋刘义庆所... 现代湘语语料显示,从历史词汇的观点而言湘语有一个层次来自六朝江东方言。有三个口语词汇可以证明上述推论:"渹"(凊)、"鼎"(铛)以及"侬"。"渹"(凊)、"鼎"(铛)出现于南朝宋刘义庆所编的《世说新语》,"侬"则来自南朝时期的文人乐府及民间歌谣。现代湘语中或多或少保留了这三个六朝江东方言词。由此可见,东晋南朝的"吴语"不仅是现代吴语、闽语的前身,也可能是现代湘语的前身。 展开更多
关键词 湘语 六朝江东方言 渹(凊) 鼎(铛)
Fabrication of Al/AlO_x/Al Josephson junctions on silicon and sapphire substrates using a cold-development technique
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作者 Wei Chen JiaZheng Pan +6 位作者 ZuYu Xu YangYang Lv XianJing Zhou XueCou Tu Jun Li GuoZhu Sun HuaBing Wang 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第6期75-80,共6页
In order to obtain high-quality superconducting qubits, we employed a cold-development technique, using temperatures down to-20°C, to fabricate Al/AlOx/Al Josephson junctions. Cold development greatly reduced the... In order to obtain high-quality superconducting qubits, we employed a cold-development technique, using temperatures down to-20°C, to fabricate Al/AlOx/Al Josephson junctions. Cold development greatly reduced the sensitivity of the electron-beam resist to the developer, eliminated molecules of the electron-beam resist at trench edges, and improved the repeatability and reliability of the nanopatterning process. The fabricated samples have well-defined geometries and increased dose margins, with lateral sizes of 100 nm×100 nm on both silicon and sapphire substrates. Together with the bridge-free fabrication method we used in these experiments, we believe that the cold-development technique can play an important role in quantum information technology that employs superconducting qubits. 展开更多
关键词 JOSEPHSON junction COLD development ELECTRON-BEAM LITHOGRAPHY insulating substrates
The Tsar Legacy: Russian Foreign Policy in the Mediterranean Area from the Romanovs to Putin 预览
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作者 Maria Teresa Giusti 《国际关系与外交:英文版》 2019年第7期325-330,共6页
This paper aims at offering an analysis of the attempts of Russian empire before, and the Soviet empire later, until to now, to exert its influence in the Mediterranean area. Drawing also from Russian archival sources... This paper aims at offering an analysis of the attempts of Russian empire before, and the Soviet empire later, until to now, to exert its influence in the Mediterranean area. Drawing also from Russian archival sources, the relations between the Soviet Union and Russia, on one side, and some countries in the Mediterranean or Adriatic areas, like former Yugoslavia or Syria, will be examined. Part of the historiography, firstly Soviet and then Russian, continued to maintain a theory, according to which Stalin’s foreign policy choices were made as a sheer reaction to English and American challenges in the region which goes from the Adriatic to the Persian Gulf. According to others, Stalin’s foreign policy was formed during and immediately after World War II and was dictated by Stalin’s personal ambitions, reinforced by the victory over Nazi Germany. However, the documents consulted until now allow for a new approach and a new evaluation of the events. The picture that emerges from an analysis of the new documentation is more complex than what could have been imagined. The clarification of the objectives and actions to be undertaken in various European countries, where communist regimes were intended to be established, was dictated by pragmatic considerations and by the development of the situation in the various countries under the Soviet influence. In addition, the USSR indirectly aimed at influencing foreign as well as internal policy in countries, such as Italy, which did not belong to the Soviet sphere. 展开更多
关键词 RUSSIAN EMPIRE Soviet foreign Policy STALIN ADRIATIC Sea YUGOSLAVIA Persian Gulf Cold War the Soviet-Yugoslav Split
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2018:The Hottest Summer in China and Possible Causes
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作者 Ting DING Yuan YUAN +1 位作者 Jianming ZHANG Hui GAO 《气象学报:英文版》 SCIE CSCD 2019年第4期577-592,共16页
In 2018,China experienced the hottest summer since 1961.The maximum,mean,and minimum temperatures all reached the highest.Air temperatures in most regions were much higher than normal;in northern China especially,the ... In 2018,China experienced the hottest summer since 1961.The maximum,mean,and minimum temperatures all reached the highest.Air temperatures in most regions were much higher than normal;in northern China especially,the temperature anomalies were above double of the standard deviations.Consistent variations of temperature anomalies appeared in the national mean and in northern China on different timescales from intraseasonal to annual,indicating that the above normal temperature in northern China contributed significantly to the record-breaking hot summer of entire China.Relationships among the high temperature in summer 2018,the tropospheric circulation,and the global sea surface temperatures(SSTs)are further analyzed.It is found that the intensified and more northward western Pacific subtropical high(WPSH),weakened Northeast China cold vortex(NECV),and positive geopotential height anomaly from northern China to the Sea of Japan resulted in the abnormally high temperature in summer 2018.From late July to mid August,the WPSH was stronger than normal,with its ridge line jumping to north of 40°N;meanwhile,the NECV was much weaker and more northward than normal;both of the two systems led to the persistent high temperature in northern China during this period.In addition,the SSTs in Kuroshio and its extension area(K–KE)in summer 2018 were also the highest since 1961 and the greatest positive SST anomaly in K–KE was favorable for the above normal geopotential height over North China–Northeast China–Japan at 500 hPa,giving rise to the exceptionally high temperature in northern China. 展开更多
关键词 summer temperature western Pacific subtropical high (WPSH) Northeast China cold vortex (NECV) atmospheric circulation Kuroshio and its extension (K-KE)
Satellite-based Observational Study of the Tibetan Plateau Vortex:Features of Deep Convective Cloud Tops 预览
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作者 Yi-Xuan SHOU Feng LU +3 位作者 Hui LIU Peng CUI Shaowen SHOU Jian LIU 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第2期189-205,248共18页
In this study,an east-moving Tibetan Plateau vortex(TPV)is analyzed by using the ERA-5 reanalysis and multi-source satellite data,including FengYun-2E,Aqua/MODIS and CALIPSO.The objective is to demonstrate:(i)the usef... In this study,an east-moving Tibetan Plateau vortex(TPV)is analyzed by using the ERA-5 reanalysis and multi-source satellite data,including FengYun-2E,Aqua/MODIS and CALIPSO.The objective is to demonstrate:(i)the usefulness of multi-spectral satellite observations in understanding the evolution of a TPV and the associated rainfall,and(ii)the potential significance of cloud-top quantitative information in improving Southwest China weather forecasts.Results in this study show that the heavy rainfall is caused by the coupling of an east-moving TPV and some low-level weather systems[a Plateau shear line and a Southwest Vortex(SWV)],wherein the TPV is a key component.During the TPV’s life cycle,the rainfall and vortex intensity maintain a significant positive correlation with the convective cloud-top fraction and height within a 2.5 radius away from its center.Moreover,its growth is found to be quite sensitive to the cloud phases and particle sizes.In the mature stage when the TPV is coupled with an SWV,an increase of small ice crystal particles and appearance of ring-and U/V-shaped cold cloud-top structures can be seen as the signature of a stronger convection and rainfall enhancement within the TPV.A tropopause folding caused by ageostrophic flows at the upper level may be a key factor in the formation of ring-shaped and U/V-shaped cloud-top structures.Based on these results,we believe that the supplementary quantitative information of an east-moving TPV cloud top collected by multi-spectral satellite observations could help to improve Southwest China short-range/nowcasting weather forecasts. 展开更多
关键词 Tibetan Plateau VORTEX MULTI-SPECTRAL SATELLITE observations short-range/nowcasting weather forecasts cold U/V-shaped cloud top TROPOPAUSE folding
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外面好冷呀!
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作者 Ruth Devlin VITALIA CHANG 《空中英语教室:初级版.大家说英语》 2019年第1期8-10,50共4页
冬季在许多地方都意味着寒冷。冬季的风暴可能会带来大雪。有时候,强风会把雪吹得漫天飞舞,使人们难以顺利开车或行走。在恶劣的天气下,学校可能会关闭,让学生待在家里。在冬季,温度会降低,而且经常会降到冰点以下。在有些地方,温度会... 冬季在许多地方都意味着寒冷。冬季的风暴可能会带来大雪。有时候,强风会把雪吹得漫天飞舞,使人们难以顺利开车或行走。在恶劣的天气下,学校可能会关闭,让学生待在家里。在冬季,温度会降低,而且经常会降到冰点以下。在有些地方,温度会降到华氏零度以下。一般人都不会待在户外的寒冷天气中,而是会待在室内保暖! 展开更多
关键词 冬季 寒冷 天气 温度 大雪 风暴 强风
Ridge Covering High-yield Cultivation Techniques of Jinhong Apple in Cold Region 预览
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作者 Chang LIU Zhangli FENG +6 位作者 Siyang TANG Haidong BU Minggang XIAO Guangjun GU Xianmin CHENG Wenquan YU Wanjun YE 《亚洲农业研究:英文版》 2019年第4期80-83,共4页
After five years of study,it was found that compared with the conventional cultivation techniques,the average yield per plant of3-5-year-old Jinhong apple trees cultivated under the ridge covering mode was increased b... After five years of study,it was found that compared with the conventional cultivation techniques,the average yield per plant of3-5-year-old Jinhong apple trees cultivated under the ridge covering mode was increased by 2. 12 times,the stem diameter was increased by20%,the branch number was increased by 73. 5%,and the underground root number was increased by 38. 3%. Under the ridge covering mode,the main distribution area of the underground roots of Jinhong apple trees was moved down to 15-55 cm,the temperature of soil 20 cm beneath the surface of the ridges increased by 1. 3-1. 5℃,the temperature of soil 40 cm beneath the surface of the ridges rose by 0. 9-1. 0℃,and the water content of soil 20-40 cm from the ground was maintained around 5%. Under the ridge covering mode,the Jinhong apple trees grew robustly,began to fruit 3 years later and yielded highly 5 years later. In addition,the ridge covering model also has illumination-enhancing,pest-controlling and tillage-free characteristics. 展开更多
关键词 COLD REGION COVERING APPLE YIELD
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基于2015年版《中国药典》(一部)挖掘和分析治疗感冒的中成药的组方规律 预览
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作者 洪海都 刘城鑫 +6 位作者 洪榆 黄慧婷 李冬婷 潘悦 陈思 陈创荣 刘小虹 《中国药房》 CAS 北大核心 2019年第13期1812-1816,共5页
目的:挖掘和分析治疗感冒的中成药的组方规律,为临床辨证用药及治疗感冒的新药研发提供参考。方法:收集2015年版《中国药典》(一部)中治疗感冒的中成药名称、剂型、处方、功能与主治,并录入中医传承辅助平台V2.5中,统计药材用药频次;运... 目的:挖掘和分析治疗感冒的中成药的组方规律,为临床辨证用药及治疗感冒的新药研发提供参考。方法:收集2015年版《中国药典》(一部)中治疗感冒的中成药名称、剂型、处方、功能与主治,并录入中医传承辅助平台V2.5中,统计药材用药频次;运用Apriori算法及关联规则对处方中核心药物组合进行统计分析(设置支持度为10%,置信度为0.65);根据无监督的熵层次聚类法提取新方组合。结果:共收集到治疗感冒的130种(包括同处方不同剂型中成药196个)中成药,包括颗粒剂(47个)、丸剂(32个)、片剂(31个)、合剂(31个)等剂型,包含264味药材;治疗感冒证型有风热证、风寒证、暑湿证、气虚证;用药频次排前3的药材为甘草(45.38%)、黄芩(32.31%)、桔梗(31.54%);常用核心药材组合28个,其中频次排前3的为甘草-桔梗、薄荷-桔梗、黄芩-连翘;挖掘出的新方组合为荆芥-桔梗-薄荷-陈皮-紫苏叶-枳壳-茯苓、连翘-黄芩-金银花-牛蒡子-淡豆豉等4首。结论:本研究通过运用中医传承辅助平台V2.5分析治疗感冒中成药的组方规律,可为临床辩证用药及研发治疗感冒新药提供参考。 展开更多
关键词 数据挖掘 感冒 中成药 组方规律 关联规则
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