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Circulation Patterns and Dynamic Drivers of Persistent Severe Rainfall over South China and the Middle-to-Lower Yangtze River Basin during 2012-21
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作者 Yongjia ZHANG Donghai WANG +1 位作者 Lingdong HUANG Enguang LI 《Advances in Atmospheric Sciences》 2026年第5期981-999,共19页
Persistent severe rainfall(PSR)events,defined as regional-scale rainfall processes with daily precipitation no less than 50 mm for at least three consecutive days,frequently occur over South China(SC)and the middle-to... Persistent severe rainfall(PSR)events,defined as regional-scale rainfall processes with daily precipitation no less than 50 mm for at least three consecutive days,frequently occur over South China(SC)and the middle-to-lower Yangtze River Basin(MLYRB),with distinct dynamic mechanisms and moisture conditions in the two regions.Based on daily precipitation observations from China’s national meteorological stations and ERA5 reanalysis during 2012-21,this study investigates the spatiotemporal distribution of PSR events in SC and MLYRB and their associated three-dimensional circulation dynamics.The analysis integrates diagnostics of 200 hPa wave activity flux,perturbation streamfunction,500 hPa geopotential height,850 hPa wind fields,and integrated water vapor transport.Results show that PSR events in SC mainly occur during May-June,with rainfall centers over coastal and central Guangdong and Guangxi.In contrast,MLYRB events peak during June-July,with a banded rainfall pattern along the middle-to-lower Yangtze River.Dynamical diagnostics indicate that,in SC,sustained northwest-southeast propagation of 200 hPa disturbances,the southward shift of the 500 hPa trough,and steady subtropical high maintenance provide continuous dynamical support.Concurrently,strong and persistent 850 hPa southwesterlies and long-lasting moisture transport form favorable moisture conditions.In contrast,MLYRB events are marked by rapid phase transitions of 200 hPa streamfunction anomalies and northward-westward expansion of the 500 hPa subtropical high,triggering intense rainfall development.Simultaneously,abrupt enhancement of 850 hPa southwesterlies and rapid formation of a southwest moisture corridor ensure abundant and timely moisture supply,facilitating PSR onset. 展开更多
关键词 persistent severe rainfall wave activity flux streamfunction anomalies integrated water vapor transport
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Ocular Microsporidiosis—Our Experience in a Tertiary Care Centre in North India
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作者 Uma Sridhar Amil Ausaf Ur Rahman +1 位作者 Jyoti Batra Neelam Sapra 《Open Journal of Ophthalmology》 2015年第3期130-138,共9页
Microsporidia are obligate intracellular protozoal parasites. They are eukaryotic and spore forming. Increasing interest in this parasite as a pathogen in the ocular tissues in recent times is due to increasing awaren... Microsporidia are obligate intracellular protozoal parasites. They are eukaryotic and spore forming. Increasing interest in this parasite as a pathogen in the ocular tissues in recent times is due to increasing awareness of microsporidia as an ocular pathogen and better methods of identification of the organism. It also can cause intestinal, sinus, pulmonary, muscular and renal diseases, in both immunocompetent and immunosuppressed patients. Ocular microsporidiosis can occur in isolation or as a part of systemic infections. In earlier published literature, ocular involvement in immunocompetent individuals was more in the form of stromal keratitis and immunocompromised individuals were seen to have keratoconjunctivitis. However, later studies show that this pattern has many variations. Occurrence in rainy season with exposure to muddy water and history of minor trauma is now a known factor. Identification by light microscopy from scrapings with KOH, Gram, Giemsa staining is possible. Growth of the organisms, however, is possible only by cell culture. Species identification is done by polymerase chain reaction and by electron microscopy. Immunofluorescent staining techniques are also available in advanced laboratories for species differentiation of microsporidia. Till date, treatment of ocular microsporidia has not been standardized and varies from simple debridement to use of various antibiotics, antiseptics antifungals and antiviral agents. 展开更多
关键词 MICROSPORIDIA KERATOCONJUNCTIVITIS STROMAL KERATITIS
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Observer-based Adaptive Fuzzy Force Control for the Pneumatic Polishing System End-actuator with Uncertain Dynamic Contact Model
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作者 Zhiguo Yang Wenbo Zhao +3 位作者 Jiange Kou Yushan Ma Yixuan Wang Yan Shi 《Chinese Journal of Mechanical Engineering》 2025年第6期366-384,共19页
In the field of flexible polishing,the accuracy of contact force control directly affects processing quality and material removal uniformity.However,the complex dynamic contact model and inherent strong hysteresis of ... In the field of flexible polishing,the accuracy of contact force control directly affects processing quality and material removal uniformity.However,the complex dynamic contact model and inherent strong hysteresis of pneumatic systems can significantly impact the force control accuracy of pneumatic polishing system end-effectors.To enhance responsiveness and control precision during the flexible polishing process,this study proposes an observer-based fuzzy adaptive control(OBFAC)scheme.To ensure control accuracy under an uncertain dynamic contact model,a fuzzy state observer is designed to estimate unmeasured states,while fuzzy logic approximates the uncertain nonlinear functions in the model to improve control performance.Additionally,the integral barrier Lyapunov function is employed to ensure that all states remain within predefined constraints.The stability of the proposed control scheme is analyzed using the Lyapunov function,and a pneumatic polishing experimental platform is constructed to conduct polishing contact force control experiments under multiple scenarios.Experimental results demonstrate that the proposed OBFAC scheme achieves superior tracking control performance compared to existing control schemes. 展开更多
关键词 Adaptive fuzzy control Pneumatic polishing system Force tracking control End-actuator
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Enhancing wastewater treatment efficiency with stereoscopic hydrogel evaporators and renewable energy integration for sustainability
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作者 unxiao Wang Yue Tian +3 位作者 Yonghang Yu Liang Wang Guangmiao Qu Shengyang Yang 《Chinese Journal of Chemical Engineering》 2025年第4期38-46,共9页
Enhancing wastewater treatment efficiency through innovative technologies is paramount in addressing global environmental challenges.This study explores utilizing stereoscopic hydrogel evaporators combined with renewa... Enhancing wastewater treatment efficiency through innovative technologies is paramount in addressing global environmental challenges.This study explores utilizing stereoscopic hydrogel evaporators combined with renewable energy sources to optimize wastewater treatment processes.A cross-linked super absorbent polymer(SAP)hydrogel was synthesized using acrylic acid and 2-hydroxyethyl methacrylate monomers and integrated with a light-absorbing carbon membrane to form a solar-assisted evaporator(MSAP).The MSAP achieved a high evaporation rate of 3.08 kg m^(-2)·h^(-1)and a photothermal conversion efficiency of 94.27%.It demonstrated excellent removal efficiency for dye-polluted wastewater,significantly reducing concentrations of pollutants.The MSAP maintained high performance in outdoor conditions,showcasing its potential for real-world applications.This approach,incorporating both solar and wind energy,significantly boosts water evaporation rates and presents a promising,eco-friendly solution for sustainable wastewater treatment within the circular development framework. 展开更多
关键词 Stereoscopic hydrogel evaporator EVAPORATION Solar energy Waste water SUSTAINABILITY
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A High-Power,Flexible,and Magnetically Attachable Radiative Cooling Film
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作者 Xianbo Nian Keng-Te Lin +7 位作者 Ke Li Jifang Hei Jihong Han Yun Li Chunsheng Guo Han Lin Jinchuan Zheng Baohua Jia 《Engineering》 2025年第6期122-133,共12页
Radiative cooling is an environmentally friendly,passive cooling technology that operates without energy consumption.Current research primarily focuses on optimizing the optical properties of radiative cooling films t... Radiative cooling is an environmentally friendly,passive cooling technology that operates without energy consumption.Current research primarily focuses on optimizing the optical properties of radiative cooling films to enhance their cooling performance.In practical applications,thermal contact between the radiative cooling film and the object significantly influences the ultimate cooling performance.However,achieving optimal thermal contact has received limited attention.In this study,we propose and experimentally demonstrate a high-power,flexible,and magnetically attachable and detachable radiative cooling film.This film consists of polymer metasurface structures on a flexible magnetic layer.The monolithic design allows for convenient attachment to and detachment from steel or iron surfaces,ensuring optimal thermal contact with minimal thermal resistance and uniform temperature distribution.Our magnetic radiative cooling film exhibits superior cooling performance compared to non-magnetic alternatives.It can reduce the temperature of stainless-steel plates under sunlight by 15.2℃,which is 3.6℃ more than that achieved by non-magnetic radiative cooling films.The radiative cooling power can reach 259W·m^(-2) at a working temperature of 70℃.Unlike other commonly used attachment methods,such as thermal grease or one-off tape,our approach allows for detachment and reusability of the cooling film according to practical needs.This method offers great simplicity,flexibility,and cost-effectiveness,making it promising for broad applications,particularly on non-horizontal irregular surfaces previously considered challenging. 展开更多
关键词 Radiative cooling Thermal management MAGNETIC FLEXIBLE Cooling power
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Protein hydrolysates from animal source food earthworm protect against dextran sulfate sodium (DSS)-induced intestinal barrier injury
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作者 Jie Pan Hui Zhao +9 位作者 Liming Jia Jinghua Jia Jingning Jia Yuhui Li Qi Tang Feiya Jiang Liang Bai Meiyan Wang Yufeng Li Zheng Wang 《Food Science and Human Wellness》 2025年第12期4776-4788,共13页
The intestinal barrier is crucial for homeostasis.This study aimed to investigate the protective effects of earthworm protein hydrolysates(EWPH)on the intestinal mucosal barrier and elucidate the underlying mechanisms... The intestinal barrier is crucial for homeostasis.This study aimed to investigate the protective effects of earthworm protein hydrolysates(EWPH)on the intestinal mucosal barrier and elucidate the underlying mechanisms.We first hydrolyzed earthworm protein using alcalase and identified the primary peptide components of EWPH through Nano LC-MS/MS analysis.Network pharmacology and bioinformatics approaches were employed to predict potential targets associated with the intestinal mucosal barrier.Experimentally,we demonstrated that EWPH effectively protects against dextran sulfate sodium(DSS)-induced intestinal barrier damage in mice.The protective mechanisms involve not only the inhibition of the Toll-like receptor 4(TLR4)-nuclear factor-kB(NF-kB)/mitogen-activated protein kinases(MAPK)signaling pathway in the intestinal epithelium but also the suppression of other key molecules implicated in intestinal mucosal barrier damage,including phosphorylated-SRC proto-oncogene(p-SRC),phosphorylated-signal transducer and activator of transcription 3(p-STAT3),Caspase-3,and matrix metalloproteinase-9(MMP9),thereby mitigating intestinal inflammation and mucosal barrier injury.This study provides evidence that EWPH have the potential to safeguard the intestinal barrier hemostasis. 展开更多
关键词 Inflammation Intestinal injury EARTHWORM Intestinal barrier CYTOKINES
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Aluminum exposure-exacerbated experimental colitis in mice was antagonized by Pueraria lobata extract
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作者 Beibei Peng Hui Zhao +7 位作者 Fan Yang Jie Pan Liang Bai Zhibo Han Wenqiang Guan Jianfu Liu Yongqing Tao Zheng Wang 《Food Science and Human Wellness》 2025年第10期3840-3849,共10页
Aluminum is the most abundant environmental pollutant.Recent studies suggest that aluminum exposure increases the risk of multiple diseases,including intestinal barrier dysfunction.We investigated whether Pueraria lob... Aluminum is the most abundant environmental pollutant.Recent studies suggest that aluminum exposure increases the risk of multiple diseases,including intestinal barrier dysfunction.We investigated whether Pueraria lobata extract(PLE)is effective in safeguarding against aluminum chloride exposureexacerbated intestinal barrier dysfunction.Using an experimental colitis model of aluminum-exacerbated dextran sulphate sodium(DSS)-treated mice,clinical and pathological evidence suggested that the administration of PLE counteracted aluminum exposure-induced intestinal barrier damage.In addition,we found that aluminum toxicities,including loss of tight junction molecules(TJs),upregulated pro-inflammatory cytokines,and enhanced myeloperoxidase(MPO)activity,were significantly suppressed by PLE administration.Furthermore,PLE administration was identified to inhibit activation of MAPKs and NF-κB signal pathways,which contribute to upregulation of myosin light-chain kinase(MLCK)in inflamed intestine.Taken together,these results suggest that PLE might be a potential candidate for aluminum exposure-related intestinal barrier dysfunction. 展开更多
关键词 Aluminum exposure Pueraria lobata extract Tight junction Intestinal barrier
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Impact of the Changbai Mountains'topography on spring fog over the Bohai Sea
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作者 Meng Tian Ying Wen +3 位作者 Lihong Meng Ye Zhang Shu Liu Yang Guo 《Atmospheric and Oceanic Science Letters》 2025年第4期54-60,共7页
Fog is a highly complex weather phenomenon influenced by numerous factors.This study investigated the impact of the Changbai Mountains’topography on the formation and development of spring fog in the Bohai Sea.From 1... Fog is a highly complex weather phenomenon influenced by numerous factors.This study investigated the impact of the Changbai Mountains’topography on the formation and development of spring fog in the Bohai Sea.From 12 to 14 May 2021,the Bohai region experienced a sea fog event.Utilizing Himawari-8 satellite data,ERA5 reanalysis dataset,land and sea station observations,the WRF model,a topography sensitivity experiment,and backward trajectory tracking,the influence of the Changbai Mountains’topography on the evolution of this sea fog event was assessed.Results indicated that the Changbai Mountains’topography significantly impacted the propagation and concentration of the sea fog through dual effects—namely,the Venturi Effect and Foehn Clearance Effect.Comparative simulations incorporating and excluding the Changbai Mountains revealed that its topography favored weak convergence(Venturi Effect)of low-level airflow over the Bohai Sea induced by a high-pressure system,promoting westward fog expansion.Additionally,the backward trajectory analysis further indicated that the Foehn Clearance Effect of the Changbai Mountains extended its influence far beyond the immediate lee side,contributing to significant changes in atmospheric conditions such as reductions in relative humidity and increases in potential temperature.The dry,warm foehn contributed to a reduction in the liquid water content,ultimately leading to the weakening or even dissipation of the sea fog in the region close to the Changbai Mountains.This study emphasizes the crucial role of the Changbai Mountains’topography in the development and evolution of fog,providing valuable insights for forecasting fog in regions with complex terrain. 展开更多
关键词 Bohai Sea Spring fog Numeral simulation TOPOGRAPHY Foehn Clearance Effect
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Elucidating Secondary Organic Aerosol Processes through High-Resolution Aerosol Mass Spectrometry in Beijing
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作者 Weiqi XU Chun CHEN +4 位作者 Zhijie LI Zhiqiang ZHANG Yu ZHANG Zifa WANG Yele SUN 《Advances in Atmospheric Sciences》 2025年第4期670-681,共12页
Exploring secondary organic aerosol(SOA)processes is crucial for understanding climate and air pollution in megacities.This study introduces a new method using positive matrix factorization(PMF)to investigate the SOA ... Exploring secondary organic aerosol(SOA)processes is crucial for understanding climate and air pollution in megacities.This study introduces a new method using positive matrix factorization(PMF)to investigate the SOA process by integrating the OA and associated ions previously misidentified as inorganic aerosol in high-resolution aerosol mass spectrometry data.The mass spectra and time series of primary OA(POA)and less oxidized oxygenated OA(OOA)identified by this new method resembled those resolved by traditional PMF.However,more oxidized OOA(MO-OOA)identified by traditional PMF can be further subdivided into multiple OA factors,including nitrogen-enriched OA(ON-OA)and sulfur-enriched OA(OS-OA)in summer,and ON-OA,OS-OA,and OOA in winter.Our findings highlight the significant role of photochemical processes in the formation of OS-OA compared to ON-OA.The compositions of reconstructed MO-OOA varied under different Ox(=O_(3)+NO_(2))and relative humidity conditions,emphasizing the limitations of using a constant mass spectrum.Aged biomass burning OA(BBOA)and coal combustion OA(CCOA),previously misattributed as POA,contributed 9.2%(0.43μg m^(−3))and 7.0%(0.33μg m^(−3))to SOA,respectively.Aged BBOA was more prone to forming OS-OA,whereas ON-OA showed higher correlations with aged CCOA,indicating distinct molecular compositions of SOA from different aged POA sources.Compared to aged BBOA,aged CCOA was more subject to conversion during aqueous phase processing.These results suggest that the variations in mass spectra and compositions need to be considered when simulating SOA processes. 展开更多
关键词 secondary organic aerosol positive matrix factorization aerosol mass spectrometry nitrogen-enriched organic aerosol sulfur-enriched organic aerosol
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Integrated photonic polarizers with 2D reduced graphene oxide
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作者 Junkai Hu Jiayang Wu +8 位作者 Di Jin Wenbo Liu Yuning Zhang Yunyi Yang Linnan Jia Yijun Wang Duan Huang Baohua Jia David J.Moss 《Opto-Electronic Science》 2025年第5期11-26,共16页
Optical polarizers,which allow the transmission of specific polarization states,are essential components in modern optical systems.Here,we experimentally demonstrate integrated photonic polarizers incorporating reduce... Optical polarizers,which allow the transmission of specific polarization states,are essential components in modern optical systems.Here,we experimentally demonstrate integrated photonic polarizers incorporating reduced graphene oxide(rGO)films.2D graphene oxide(GO)films are integrated onto silicon waveguides and microring resonators(MRRs)with precise control over their thicknesses and sizes,followed by GO reduction via two different methods including uniform thermal reduction and localized photothermal reduction.We measure devices with various lengths,thicknesses,and reduction degrees of GO films.The results show that the devices with rGO exhibit better performance than those with GO,achieving a polarization-dependent loss of~47 dB and a polarization extinction ratio of~16 dB for the hybrid waveguides and MRRs with rGO,respectively.By fitting the experimental results with theory,it is found that rGO exhibits more significant anisotropy in loss,with an anisotropy ratio over 4 times that of GO.In addition,rGO shows higher thermal stability and greater robustness to photothermal reduction than GO.These results highlight the strong potential of rGO films for implementing high-performance polarization selective devices in integrated photonic platforms. 展开更多
关键词 integrated optics 2D materials graphene oxide optical polarizers
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A Noble Metal High-Entropy Alloy for Mid-Infrared Metasurfaces
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作者 Yoshiaki Nishijima Teruaki Sudo +1 位作者 Yasutaka Matsuo Saulius Juodkazis 《Engineering》 2025年第6期81-89,共9页
High-entropy alloys(HEAs)are promising materials for photonic applications.In such applications,permittivity is essential for numerical studies.In this work,we experimentally determine the complex permittivity of an H... High-entropy alloys(HEAs)are promising materials for photonic applications.In such applications,permittivity is essential for numerical studies.In this work,we experimentally determine the complex permittivity of an HEA composed of five noble metals-Au,Ag,Cu,Pd,and Pt.The measurements are conducted across a broad wavelength spectrum,spanning the ultraviolet,visible,and mid-infrared regions.The experiments,numerical simulations of reflection spectra,and analysis of absorption and scattering cross-sections reveal the potential for fabricating perfect absorber and emitter metasurfaces using this noble HEA.In addition,crystallography studies clearly show the formation of a uniform material.The lattice constant and electron work function of the alloy are found to be 0.396 nm and(4.8±0.4)eV,respectively-results indicate that the formed HEA alloy is well mixed. 展开更多
关键词 High-entropy alloy Metasurfaces PLASMONICS
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英语变体研究对大学英语教学的启示——以非洲赞比亚英语为例 被引量:1
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作者 乔丽苹 Alfred Mbeba 《英语广场》 2015年第2期77-79,共3页
英语在本土化演变中产生了不同的国别变体。这种变体研究的理论成果对大学英语教学实践具有很强的启示性和借鉴性。非洲赞比亚英语是英语变体研究中的一个典型代表,它以英国英语为标准,语法、句法上仍遵循英国英语的基本框架和脉络,但... 英语在本土化演变中产生了不同的国别变体。这种变体研究的理论成果对大学英语教学实践具有很强的启示性和借鉴性。非洲赞比亚英语是英语变体研究中的一个典型代表,它以英国英语为标准,语法、句法上仍遵循英国英语的基本框架和脉络,但在语音、词汇、句法等方面又表现出较大的差异性,尤其是口语语体。大学英语教学实践中,师生应增强英语变体教学意识,基于英语变体研究成果在教学内容和教学方法上进一步完善,以提高大学英语教学的时效性和学生在国际化英语语境中的交际能力。 展开更多
关键词 英语变体 大学英语教学 赞比亚英语 交际能力
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Possible Impacts of the Arctic Oscillation on the Interdecadal Variation of Summer Monsoon Rainfall in East Asia 被引量:43
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作者 琚建华 吕俊梅 +1 位作者 曹杰 任菊章 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第1期39-48,共10页
The influences of the wintertime AO (Arctic Oscillation) on the interdecadal variation of summer monsoon rainfall in East Asia were examined. An interdecadal abrupt change was found by the end of the 1970s in the vari... The influences of the wintertime AO (Arctic Oscillation) on the interdecadal variation of summer monsoon rainfall in East Asia were examined. An interdecadal abrupt change was found by the end of the 1970s in the variation of the AO index and the leading principal component time series of the summer rainfall in East Asia. The rainfall anomaly changed from below normal to above normal in central China, the southern part of northeastern China and the Korean peninsula around 1978. However, the opposite interdecadal variation was found in the rainfall anomaly in North China and South China. The interdecadal variation of summer rainfall is associated with the weakening of the East Asia summer monsoon circulation. It is indicated that the interdecadal variation of the AO exerts an influence on the weakening of the monsoon circulation. The recent trend in the AO toward its high-index polarity during the past two decades plays important roles in the land-sea contrast anomalies and wintertime precipitation anomaly. The mid- and high-latitude regions of the Asian continent are warming, while the low-latitude regions are cooling in winter and spring along with the AO entering its high-index polarity after the late 1970s. In the meantime, the precipitation over the Tibetan Plateau and South China is excessive, implying an increase of soil moisture. The cooling tendency of the land in the southern part of Asia will persist until summer because of the memory of soil moisture. So the warming of the Asian continent is relatively slow in summer. Moreover, the Indian Ocean and Pacific Ocean, which are located southward and eastward of the Asian land, are warming from winter to summer. This suggests that the contrast between the land and sea is decreased in summer. The interdecadal decrease of the land-sea heat contrast finally leads to the weakening of the East Asia summer monsoon circulation. 展开更多
关键词 the Arctic Oscillation interdecadal variation summer monsoon rainfall land-sea heat contrast
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A Review of Recent Advances in Research on Asian Monsoon in China 被引量:16
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作者 何金海 琚建华 +2 位作者 温之平 吕俊梅 金放华 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第6期972-992,共21页
This paper reviews briefly advances in recent research on monsoon by Chinese scholars, including primarily: (1) the establishment of various monsoon indices. In particular, the standardized dynamic seasonal variabi... This paper reviews briefly advances in recent research on monsoon by Chinese scholars, including primarily: (1) the establishment of various monsoon indices. In particular, the standardized dynamic seasonal variability index of the monsoon can delimit the geographical distribution of global monsoon systems and determine quantitatively the date of abrupt change in circulation. (2) The provision of three driving forces for the generation of monsoon. (3) The revelation of the heating-pump action of the Tibetan Plateau, which strengthens southerlies in the southern and southeastern periphery of the Plateau and results in a strong rainfall center from the northern Bay of Bengal (BOB) to the Plateau itself. (4) Clarification of the initial onset of the Asian Summer Monsoon (ASM) in the BOB east of 90°E, Indochina Peninsula (ICP) and the South China Sea, of which the rapid northward progression of tropical convection in the Sumatra and the rapid westward movement of the South Asia High to the Indochina Peninsula are the earliest signs. (5) The provision of an integrated mechanism for the onset of the East Asian Summer Monsoon (EASM), which emphasizes the integrated impact of sensible heat over Indian Peninsula, the warm advection of the Tibetan Plateau and the sensible heat and latent heat over the Indochina Peninsula on the one hand, and the seasonal phase-lock effect of the northward propagation of low frequency oscillation on the other. (6) The revelation of the "planetary-scale moisture transport large-value band" from the Southern Hemisphere through to the Asian monsoon region and into the North Pacific, which is converged by several large-scale moisture transport belts in the Asian-Australian monsoon regions and whose variation influences directly the temporal and spatial distribution of summer rainfall in China. (7) Presenting the features of the seasonal advance of the EASM, the propagation of intraseasonal oscillation, and their relationship with rainfall in China; indicating that the intraseasonal oscillation of the EASM propagates in the form of a wave-train along the coast and behaves as monsoon surge propagating northward. (8) Describing the interannual and interdecadal variation of Asian monsoon, revealing the factors affecting it, and possible mechanisms of the variation of Asian monsoon. An elementary outlook on the existing problems and future direction of monsoon research is also provided. 展开更多
关键词 recent research MONSOON China review ADVANCES existing problems PROSPECTS
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Enhancement of the Summer North Atlantic Oscillation Influence on Northern Hemisphere Air Temperature 被引量:13
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作者 袁薇 孙建奇 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第6期1209-1214,共6页
This study investigates the relationship between the summer North Atlantic Oscillation (SNAO) and the simultaneous Northern Hemisphere (NH) land surface air temperature (SAT) by using the Climate Research Unit ... This study investigates the relationship between the summer North Atlantic Oscillation (SNAO) and the simultaneous Northern Hemisphere (NH) land surface air temperature (SAT) by using the Climate Research Unit (CRU) data. The results show that the SNAO is related to NH land SAT, but this linkage has varied on decadal timescales over the last 52 years, with a strong connection appearing after the late 1970s, but a weak connection before. The mechanism governing the relationship between the SNAO and NH land SAT is discussed based on the NCEP/NCAR reanalysis data. The results indicate that such a variable relationship may result from changes of the SNAO mode around the late 1970s. The SNAO pattern was centered mainly over the North Atlantic before the late 1970s, and thus had a weak influence on the NH land SAT. But after the late 1970s, the SNAO pattern shifted eastward and its southern center was enhanced in magnitude and extent, which transported the SNAO signal to the North Atlantic surrounding continents and even to central East Asia via an upper level wave train along the Asian jet. 展开更多
关键词 Summer North Atlantic Oscillation surface air temperature wave train
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军事飞行人员疲劳状况调查与分析(英文) 被引量:6
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作者 郭建生 陈士伟 +5 位作者 白菁 李娜 马峥嵘 沈嘉平 季思菊 应淑辉 《解放军医学杂志》 CAS CSCD 北大核心 2012年第3期249-252,共4页
目的了解军事飞行人员的疲劳状况及其特点与影响因素。方法采用疲劳评定量表(FAI)和疲劳量表(FS-14)对924例军事飞行人员进行问卷调查,数据结果采用SPSS 17.0软件进行χ2检验及Pearson相关分析。结果问卷调查结果显示,疲劳症状阳性343人... 目的了解军事飞行人员的疲劳状况及其特点与影响因素。方法采用疲劳评定量表(FAI)和疲劳量表(FS-14)对924例军事飞行人员进行问卷调查,数据结果采用SPSS 17.0软件进行χ2检验及Pearson相关分析。结果问卷调查结果显示,疲劳症状阳性343人(37.1%),阴性581人(62.9%),疲劳症状阳性组FAI因子1(疲劳严重程度)、因子2(脑力疲劳因子)、因子3(疲劳后果)及总分和FS-14因子1(躯体疲劳因子)及总分均高于疲劳症状阴性组,差异有统计学意义(P<0.01)。年龄及飞行时间不同者出现疲劳症状的概率不同,差异有统计学意义(P<0.01,P<0.05),而飞行机种不同者出现疲劳症状的概率差异无统计学意义(P>0.05)。年龄、飞行时间与FAI因子1及总分和FS-14因子1、因子2及总分呈正相关,而飞行机种与FAI各因子及总分和FS-14各因子及总分均无相关性。结论军事飞行人员出现疲劳症状比较普遍,其特点是疲劳严重程度、环境特异性、疲劳的后果、躯体疲劳等维度表现较明显,且不同年龄和飞行时间出现疲劳症状的概率不同。 展开更多
关键词 飞行员 军事人员 疲劳 问卷调查
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Spatiotemporal variability of precipitation during 1961-2014 across the Mongolian Plateau 被引量:13
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作者 QIN Fu-ying JIA Gen-suo +3 位作者 YANG Jie NA Yin-tai HOU Mei-ting Narenmandula 《Journal of Mountain Science》 SCIE CSCD 2018年第5期992-1005,共14页
Precipitation is the dominant factor that controls vegetation growth and land-use practices in the arid and semiarid Mongolian Plateau(MP), so the spatiotemporal heterogeneity of precipitation change has been an impor... Precipitation is the dominant factor that controls vegetation growth and land-use practices in the arid and semiarid Mongolian Plateau(MP), so the spatiotemporal heterogeneity of precipitation change has been an important scientific question in the region. This study investigated the spatiotemporal characteristics of annual and seasonal precipitation across the entire MP based on monthly precipitation data from 136 meteorological stations during 1961–2014 by using a modified Mann–Kendall test, Sen's slope, Morlet Wavelet Transform, and geostatistical methods. Results show the following: 1) Annual precipitation decreased slightly from 1961 to 2014.Stations with positive and negative trends were 41.9%and 58.1%, respectively. Significant positive trends were mainly in the southwestern and northeastern regions of the plateau, whereas significant negative trends were in the northern and southeastern regions.2) Precipitation decreased at rates of-5.65 and-0.41 mm/decade in summer and autumn, respectively, but increased at 1.91 and 0.51 mm/decade in spring and winter. The contribution of spring and winter precipitation to the annual amount increased significantly, but that of summer precipitation decreased significantly. 3) A large majority of stations(80.2%) showed decreasing trends in summer,whereas 89.7% and 83.1% of stations showed increasing trends in spring and winter. The spatial distribution of trend magnitude in seasonal precipitation amount was strongly heterogeneous. 4)By climatic zones, precipitation increased in humid and arid zones, but decreased in a semiarid zone. On the whole, the MP experienced a drying trend, with significant regional differentiation and seasonal variations. 展开更多
关键词 PRECIPITATION INTERANNUAL trends SEASONAL variability SPATIOTEMPORAL characteristics MONGOLIAN PLATEAU
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Using multi-satellite microwave remote sensing observations for retrieval of daily surface soil moisture across China 被引量:9
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作者 Ke Zhang Li-jun Chao +6 位作者 Qing-qing Wang Ying-chun Huang Rong-hua Liu Yang Hong Yong Tu Wei Qu Jin-yin Ye 《Water Science and Engineering》 EI CAS CSCD 2019年第2期85-97,共13页
The objective of this study was to retrieve daily composite soil moisture by jointly using brightness temperature observations from multiple operating satellites for near real-time application with better coverage and... The objective of this study was to retrieve daily composite soil moisture by jointly using brightness temperature observations from multiple operating satellites for near real-time application with better coverage and higher accuracy.Our approach was to first apply the single-channel brightness radiometric algorithm to estimate soil moisture from the respective brightness temperature observations of the SMAP,SMOS,AMSR2,FY3B,and FY3C satellites on the same day and then produce a daily composite dataset by averaging the individual satellite-retrieved soil moisture.We further evaluated our product,the official soil moisture products of the five satellites,and the ensemble mean (i.e.,arithmetic mean) of the five official satellite soil moisture products against ground observations from two networks in Central Tibet and Anhui Province,China.The results show that our product outperforms the individual released products of the five satellites and their ensemble means in the two validation areas.The root mean square error (RMSE ) values of our product were 0.06 and 0.09 m3/m3 in Central Tibet and Anhui Province,respectively.Relative to the ensemble mean of the five satellite products,our product improves the accuracy by 9.1% and 57.7% in Central Tibet and Anhui Province,respectively.This demonstrates that jointly using brightness temperature observations from multiple satellites to retrieve soil moisture not only improves the spatial coverage of daily observations but also produces better daily composite products. 展开更多
关键词 Soil MOISTURE RETRIEVAL Passive microwave remote sensing Multiple SATELLITES Surface HYDROLOGY SMAP SMOS AMSR2 FY3B FY3C
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Constitutive behavior of Ni-Ti shape memory alloy under hot compression 被引量:5
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作者 江树勇 张艳秋 +2 位作者 赵亚楠 唐明 易文林 《Journal of Central South University》 SCIE EI CAS 2013年第1期24-29,共6页
Constitutive behavior of nickel-titanium shape memory alloy (Ni-Ti SMA) under hot deformation was investigated by means of the compression tests and the linear fitting method. Based on the true stres-strain curves o... Constitutive behavior of nickel-titanium shape memory alloy (Ni-Ti SMA) under hot deformation was investigated by means of the compression tests and the linear fitting method. Based on the true stres-strain curves of Ni-Ti SMA under compression at the strain rates of 0.001-1 s land at the temperatures ranging from 600 to 1 000 ℃, the constitutive equation of Ni-Ti SMA with respect to the Zener-Hollomon parameter was established according to the high stress level and the low stress level at various temperatures so as to more accurately describe the deformation behavior of Ni-Ti SMA during hot working. Dynamic recovery and dynamic recrystallization of Ni-Ti SMA occur under hot compression, which lays the theoretical foundation for understanding the constitutive behavior of Ni-Ti SMA. 展开更多
关键词 Ni-Ti alloy shape memory alloy constitutive behavior microstructural evolution hot deformation
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Influence of October Eurasian Snow on Winter Temperature over Northeast China 被引量:5
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作者 Huanlian LI Huijun WANG Dabang JIANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第1期116-126,共11页
This paper addresses the interannual variation of winter air temperature over Northeast China and its connection to preceding Eurasian snow cover. The results show that there is a significant negative correlation betw... This paper addresses the interannual variation of winter air temperature over Northeast China and its connection to preceding Eurasian snow cover. The results show that there is a significant negative correlation between October Eurasian snow cover and following-winter air temperature over Northeast China. The snow cover located in eastern Siberia and to the northeast of Lake Baikal plays an important role in the winter air temperature anomaly. More (less) eastern Siberia snow in October can cause an atmospheric circulation anomaly pattern in which the atmospheric pressure is higher (lower) than normal in the polar region and lower (higher) in the northern mid-high latitudes. Due to the persistence of the eastern Siberia snow from October to the following winter, the winter atmospheric anomaly is favorable (unfavorable) to the widespread movement of cold air masses from the polar region toward the northern mid-high latitudes and, hence, lower (higher) temperature over Northeast China. Simultaneously, when the October snow cover is more (less), the SST in the northwestern Pacific is continuously lower (higher) as a whole; then, the Aleutian low and the East Asia trough are reinforced (weakened), favoring the lower (higher) temperature over Northeast China. 展开更多
关键词 winter air temperature Northeast China Eurasian snow cover physical mechanism atmospheric circulationanomaly
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