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Spatial distribution and filtering efficiency of Daphnia in a deep subtropical reservoir 预览
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作者 ZHANG Man SMYTH Rebecca Ashley +6 位作者 ZHU Weixia ZHANG Li LI Yuncong WANG Yifan LI Xuejun GU Qianhong GAO Yunni 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第4期1277-1288,共12页
Studies of Daphnia distribution and function could help people manage and protect water quality. We investigated how spatial distribution and filtering efficiency of Daphnia in the transition and lacustrine zones of t... Studies of Daphnia distribution and function could help people manage and protect water quality. We investigated how spatial distribution and filtering efficiency of Daphnia in the transition and lacustrine zones of the Nanwan Reservoir (China). Samplings were conducted seasonally for 2 years from six sites in the reservoir. Daphnia abundance and biomass were significantly higher in the lacustrine zone than in the transition zone. Similar composition and biomass of edible phytoplankton were found in the two zones, suggesting that food quantity could not explain high Daphnia distribution in the lacustrine zone. The variations of water velocity and food quality could help explaining Daphnia patchy distribution in the reservoir. On the one hand, rapid water velocity can cause the Daphnia decrement in the transition zone. On the other hand, the ratio of particulate organic carbon (POC) to chlorophyll a (chl a) concentration was significantly higher in the transition zone, indicating more allochthonous material constituted the food source for Daphnia. The lower quality food likely suppressed Daphnia development in the transition zone. A linear regression between Daphnia abundance and Secchi depth (SD) may suggest a cause-effect relationship where increased filtering efficiency was responsible for increased water clarity to some extent. 展开更多
关键词 DAPHNIA LACUSTRINE ZONE transition ZONE water CLARITY Nanwan RESERVOIR
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Main Characteristics of Dust Storms and Their Radiative Impacts: With a Focus on Tajikistan 预览
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作者 Sabur.F.Abdullaev Irina.N.Sokolik 《大气科学研究(英文)》 2019年第2期1-21,共21页
known aridity of the region is a major factor in promoting numerous dust storms. They have many diverse impacts on the environment and the climate of the region. The classification of dust storms and synoptic conditio... known aridity of the region is a major factor in promoting numerous dust storms. They have many diverse impacts on the environment and the climate of the region. The classification of dust storms and synoptic conditions related to their formation in Central Asia are discussed in the content of their diverse impact. We address dust optical properties that are representative of the region. Dust storms significantly reduce visibly and pose a human health threads. They also cause a significant impact on the radiative regime. As a result, dust storms may cause a decrease in temperature during daytime of up to 16℃ and an increase in temperature during night time from up to 7℃ compared to a clear day. 展开更多
关键词 DUST storms DUST haze Temperature effect of AEROSOL AEROSOL optical thickness Desert ZONE ARID ZONE DUST AEROSOL
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Sodium valproate suppresses abnormal neurogenesis induced by convulsive status epilepticus 预览
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作者 Peng Wu Yue Hu +2 位作者 Xiu-Juan Li Min Cheng Li Jiang 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第3期480-484,共5页
Status epilepticus has been shown to activate the proliferation of neural stem cells in the hippocampus of the brain, while also causing a large amount of neuronal death, especially in the subgranular zone of the dent... Status epilepticus has been shown to activate the proliferation of neural stem cells in the hippocampus of the brain, while also causing a large amount of neuronal death, especially in the subgranular zone of the dentate gyrus and the subventricular zone. Simultaneously, proliferating stem cells tend to migrate to areas with obvious damage. Our previous studies have clearly confirmed the effect of sodium valproate on cognitive function in rats with convulsive status epilepticus. However, whether neurogenesis can play a role in the antiepileptic effect of sodium valproate remains unknown. A model of convulsive status epilepticus was established in Wistar rats by intraperitoneal injection of 3 mEq/kg lithium chloride, and intraperitoneal injection of pilocarpine 40 mg/kg after 18–20 hours. Sodium valproate(100, 200, 300, 400, 500, or 600 mg/kg) was intragastrically administered six times every day(4-hour intervals) for 5 days. To determine the best dosage, sodium valproate concentration was measured from the plasma. The effective concentration of sodium valproate in the plasma of the rats that received the 300-mg/kg intervention was 82.26 ± 11.23 μg/mL. Thus, 300 mg/kg was subsequently used as the intervention concentration of sodium valproate. The following changes were seen: Recording excitatory postsynaptic potentials in the CA1 region revealed high-frequency stimulation-induced long-term potentiation. Immunohistochemical staining for BrdU-positive cells in the brain revealed that sodium valproate intervention markedly increased the success rate and the duration of induced long-term potentiation in rats with convulsive status epilepticus. The intervention also reduced the number of newborn neurons in the subgranular area of the hippocampus and subventricular zone and inhibited the migration of newborn neurons to the dentate gyrus. These results indicate that sodium valproate can effectively inhibit the abnormal proliferation and migration of neural stem cells and newborn neurons after convulsive status epile 展开更多
关键词 nerve REGENERATION status epilepticus sodium valproate long-term POTENTIATION NEURAL stem cells NEUROGENESIS migration subgranular ZONE subventricular ZONE NEURAL REGENERATION
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National Ecological Civilization Pilot Zone(Hainan) Implementation Scheme Released
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作者 Qian Fang(译) 《城市规划:英文版》 CSCD 2019年第2期4-5,共2页
On May 12,2019,the CPC Central Committee and the State Council released the National Ecological Civilization Pilot Zone(Hainan)Implementation Scheme(shortened into the Implementation Scheme in the following part).Acco... On May 12,2019,the CPC Central Committee and the State Council released the National Ecological Civilization Pilot Zone(Hainan)Implementation Scheme(shortened into the Implementation Scheme in the following part).According to the Implementation Scheme,by2020,the proportion of area within the ecological protection red line on land area of Hainan should be no less than 27.3%,and the proportion of area within the ecological protection red line in the offshore area in the total offshore area of Hainan should be no less than 35.1%. 展开更多
关键词 HAINAN Implementation Scheme RELEASED NATIONAL Ecological CIVILIZATION PILOT ZONE
Ratcheting Behavior of Weld Joints Under Uniaxial Cyclic Loading Using Miniature Specimen 预览
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作者 Jiankai Tang Zhe Zhang +1 位作者 Hongsheng Lu Xu Chen 《天津大学学报:英文版》 EI CAS 2019年第3期283-292,共10页
Because of the size limitation of weld joints in different regions,the traditional standard bar specimen is not suitable to investigate the mechanical properties of weld joints.In this study,miniature specimens were e... Because of the size limitation of weld joints in different regions,the traditional standard bar specimen is not suitable to investigate the mechanical properties of weld joints.In this study,miniature specimens were extracted from specific regions(base metal,weld metal,and three heat-affected zones) of API X80 and X70 weld joints.Uniaxial tensile tests were conducted to obtain the mechanical properties of different regions,and then uniaxial ratcheting tests were conducted to investigate the ratcheting behaviors of the different regions under the same peak and nominal stresses.Under both the tensile tests and ratcheting tests,the weld joints exhibit heterogeneous results,such as different mechanical properties and ratcheting behaviors,which were region dependent.Furthermore,the yield strength and yield-to-tensile strength ratio contribute differently to the ratcheting response. 展开更多
关键词 RATCHETING Weld joints Heat-affected zone MINIATURE SPECIMEN HETEROGENEITY
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Models of steam-assisted gravity drainage(SAGD) steam chamber expanding velocity in double horizontal wells and its application 预览
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作者 ZHOU You LU Teng +3 位作者 WU Shouya SHI Lanxiang DU Xuan WANG Junling 《石油勘探与开发:英文版》 2019年第2期347-354,共8页
The development of steam chamber can be used to evaluate steam-assisted gravity drainage(SAGD) performance. The velocity of steam chamber expanding is the key parameter for evaluating the development of steam chamber.... The development of steam chamber can be used to evaluate steam-assisted gravity drainage(SAGD) performance. The velocity of steam chamber expanding is the key parameter for evaluating the development of steam chamber. Based on SAGD technology theory and heat transfer theory, two calculation model methods, observation well temperature method and steam chamber edge method for estimating the horizontal expanding velocity of steam chamber, were presented. Through analyzing the monitoring data and numerical simulation results of a typical super heavy oil block developed by SAGD in Fengcheng oilfield in Xinjiang, NW China, the development patterns of steam chamber and temperature variation law in the observation well at different stages are determined. The observed temperature data was used to calculate steam chamber expanding velocity. The calculated chamber velocity at different time was applied to predict the temperature distribution of oil drainage zone at the edge of steam chamber and SAGD oil rate. The results indicate that temperature function of high temperature zone in the observation well temperature curve has a linear relationship with measuring depth.The characteristic section can be used to calculate key parameters such as the angle of the drainage interface, expanding edge and velocity of steam chamber. The field production data verify that the results of the two proposed methods of steam chamber growth are reliable and practical, which can provide theoretical support for the efficient development of SAGD. 展开更多
关键词 steam-assisted GRAVITY drainage observation well temperature STEAM CHAMBER STEAM CHAMBER EXPANDING VELOCITY oil drainage zone
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Subduction-zone peridotites and their records of crust-mantle interaction
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作者 Jianping ZHENG Qing XIONG +1 位作者 Yi ZHAO Wenbo LI 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第7期1033-1052,共20页
Subduction is the core process of plate tectonics. The mantle wedge in subduction-zone systems represents a key tectonic unit, playing a significant role in material cycling and energy exchange between Earth’s layers... Subduction is the core process of plate tectonics. The mantle wedge in subduction-zone systems represents a key tectonic unit, playing a significant role in material cycling and energy exchange between Earth’s layers. This study summarizes research progresses in terms of subduction-related peridotite massifs, including supra-subduction zone(SSZ) ophiolites and mantle-wedge-type(MWT) orogenic peridotites. We also provide the relevant key scientific questions that need be solved in the future. The mantle sections of SSZ ophiolites and MWT orogenic peridotites represent the mantle fragments from oceanic and continental lithosphere in subduction zones, respectively. They are essential targets to study the crust-mantle interaction in subduction zones. The nature of this interaction is the complex chemical exchanges between the subducting slab and the mantle wedge under the major control of physical processes. The SSZ ophiolites can record melt/fluid-rock interaction, metamorphism,deformation, concentration of metallogenic elements and material exchange between crust and mantle, during the stages from the generation of oceanic lithosphere at spreading centers to the initiation, development, maturation and ending of oceanic subduction at continental margins. The MWT orogenic peridotites reveal the history of strong metamorphism and deformation during subduction, the multiple melt/fluid metasomatism(including silicatic melts, carbonatitic melts and silicate-bearing C-HO fluids/supercritical fluids), and the complex cycling of crust-mantle materials, during the subduction/collision and exhumation of continental plates. In order to further reveal the crust-mantle interaction using subduction-zone peridotites, it is necessary to utilize high-spatial-resolution and high-precision techniques to constrain the complex chemical metasomatism, metamorphism,deformation at micro scales, and to reveal their connections with spatial-temporal evolution in macro-scale tectonics. 展开更多
关键词 Subduction zone Ophiolite OROGENIC PERIDOTITE Mantle wedge METASOMATISM CRUST-MANTLE interaction
Characteristics of flow and heat transfer of shell-and-tube heat exchangers with overlapped helical baffles
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作者 Tingting DU Wenjing DU 《工程管理前沿:英文版》 2019年第1期70-77,共8页
The characteristics of flow and heat transfer of shell-and-tube heat exchangers with overlapped helical baffles (STHXsHB) were illustrated through a theoretical analysis and numerical simulation. The ideal helical flo... The characteristics of flow and heat transfer of shell-and-tube heat exchangers with overlapped helical baffles (STHXsHB) were illustrated through a theoretical analysis and numerical simulation. The ideal helical flow model was constructed to demonstrate parts of the flow characteristics of the STHXsHB, providing theoretical evidence of short-circuit and back flows in a triangular zone. The numerical simulation was adopted to describe the characteristics of helical, leakage, and bypass streams. In a fully developed section, the distribution of velocity and wall heat transfer coefficient has a similar trend, which presents the effect of leakage and bypass streams. The short-circuit flow accelerates the axial velocity of the flow through the triangular zone. Moreover, the back flow enhances the local heat transfer and causes the ascent of flow resistance. This study shows the detailed features of helical flow in STHXsHB, which can inspire a reasonable optimization on the shell-side structure. 展开更多
关键词 HEAT EXCHANGER overlapped HELICAL BAFFLE TRIANGULAR ZONE HELICAL flow
Recent Progress in Studies of the Variabilities and Mechanisms of the East Asian Monsoon in a Changing Climate 预览
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作者 Wen CHEN Lin WANG +4 位作者 Juan FENG Zhiping WEN Tiaojiao MA Xiuqun YANG Chenghai WANG 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第9期887-901,共15页
Located in a monsoon domain,East Asia suffers devastating natural hazards induced by anomalous monsoon behaviors.East Asian monsoon(EAM)research has traditionally been a high priority for the Chinese climate community... Located in a monsoon domain,East Asia suffers devastating natural hazards induced by anomalous monsoon behaviors.East Asian monsoon(EAM)research has traditionally been a high priority for the Chinese climate community and is particularly challenging in a changing climate where the global mean temperature has been rising.Recent advances in studies of the variabilities and mechanisms of the EAM are reviewed in this paper,focusing on the interannual to interdecadal time scales.Some new results have been achieved in understanding the behaviors of the EAM,such as the evolution of the East Asian summer monsoon(EASM),including both its onset and withdrawal over the South China Sea,the changes in the northern boundary activity of the EASM,or the transitional climate zone in East Asia,and the cycle of the EASM and the East Asian winter monsoon and their linkages.In addition,understanding of the mechanism of the EAM variability has improved in several aspects,including the impacts of different types of ENSO on the EAM,the impacts from the Indian Ocean and Atlantic Ocean,and the roles of mid-to high-latitude processes.Finally,some scientific issues regarding our understanding of the EAM are proposed for future investigation. 展开更多
关键词 EAST ASIAN summer MONSOON EAST ASIAN winter MONSOON CHANGING CLIMATE MONSOON onset and withdrawal transitional CLIMATE zone different types of ENSO
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Characterization of focusing performance of spiral zone plates with fractal structure
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作者 臧华平 郑程龙 +10 位作者 吉子雯 范全平 魏来 李永杰 牧凯军 陈述 王传珂 朱效力 谢常青 曹磊峰 梁二军 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第6期184-188,共5页
We propose an efficient method of generating a vortex beam with multi-foci by using a fractal spiral zone plate(FSZP), which is designed by combining fractal structure with a spiral zone plate(SZP) in the squared radi... We propose an efficient method of generating a vortex beam with multi-foci by using a fractal spiral zone plate(FSZP), which is designed by combining fractal structure with a spiral zone plate(SZP) in the squared radial coordinate.The theoretical analysis reveals that the number of foci that embed vortices is significantly increased as compared with that obtained by using a conventional SZP. Furthermore, the influence of topological charge on the intensity distribution in focal plane is also discussed in detail. For experimental investigation, an FSZP with topological charge p = 1 and 6.4 mm diameter is fabricated by using a photo-etching technique. The calibration indicates that the focusing performances of such a kind of zone plane(ZP) accord well with simulations, thereby providing its potential applications in multi-dimensional optical manipulation and optical imaging technology. 展开更多
关键词 OPTICAL VORTICES SPIRAL ZONE PLATE DIFFRACTIVE OPTICAL elements
A GEM OF THE BELT AND ROAD The China-Indonesia Economic and Trade Cooperation Zone has become a draw for Chinese investors 预览
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作者 Wang Fang Wang Fengjuan 《中国东盟报道》 2019年第1期28-31,共4页
A 37-kilometer drive northeast along the Jakarta-Bandung expressway from downtown Jakarta is Bekasi,home of the Greenland International Industrial Center(GIIC).With residents including Kawasan Industri Terpadu Indones... A 37-kilometer drive northeast along the Jakarta-Bandung expressway from downtown Jakarta is Bekasi,home of the Greenland International Industrial Center(GIIC).With residents including Kawasan Industri Terpadu Indonesia China(KITIC),also known as China-Indonesia Economic and Trade Cooperation Zone,GIIC has been dubbed the“East Jakarta Corridor.” 展开更多
关键词 the BELT and ROAD Economic and trade cooperation ZONE The highway
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Influence of work zone signage on driver speeding behavior 预览
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作者 Snehanshu Banerjee Mansoureh Jeihani Nashid K.Khadem 《现代交通学报:英文版》 2019年第1期52-60,共9页
Speeding in a work zone needs to be tackled effectively to enhance work zone safety.This study evaluates the influence of three different work zone signs— speed photo enforced signs,dynamic speed display signs and re... Speeding in a work zone needs to be tackled effectively to enhance work zone safety.This study evaluates the influence of three different work zone signs— speed photo enforced signs,dynamic speed display signs and reduced speed limit signs—on driver speeding behavior using a medium-fidelity driving simulator.The speed photo enforced and reduced speed limit signs were placed at intervals before the start of the work zone and in the work zone.A virtual work zone network was built to replicate the Baltimore–Washington Parkway(MD-295).A total of 66 participants from different socioeconomic backgrounds participated in 264 driving simulation sessions.The speeds were measured over four phases:initial speed area,sign visible area,sign readable area and post sign area.An analysis of variance and post hoc analysis showed that the speed photo enforced sign was the most effective of the three signs.The second speed photo enforced sign within the work zone was more effective at reducing speed than the sign before the start of the work zone,especially in the post sign area.It was observed that female participants tend to slow down more when encountering a speed photo enforcement sign. 展开更多
关键词 Work zone Driving SIMULATOR SPEED study SPEED photo enforced SIGN Dynamic SPEED display SIGN Reduced SPEED LIMIT SIGN
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The Nature of No-Fly Zones in International Relations 预览
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作者 Zhao Guangcheng 《现代国际关系:英文版》 2019年第3期68-85,共18页
A No-Fly Zone (NFZ) is a unique mode of humanitarian intervention that is understudied in international relations. This article focuses on the politics of NFZs in international relations, and investigates their nature... A No-Fly Zone (NFZ) is a unique mode of humanitarian intervention that is understudied in international relations. This article focuses on the politics of NFZs in international relations, and investigates their nature by empirically reviewing all three cases of NFZs to date. NFZs represent a middle ground for international intervention which, both legally and legitimately, may be aimed at either protecting populations or promoting regime change in weak states, depending on the circumstances. There may be efforts by intervening states to highlight humanitarian crises among certain targets in order to secure UN authorization for the NFZs;but the implementation of NFZs is also largely driven by the security interests of the enforcing states. As a result, there is the potential for those states implementing NFZs to transcend legal authorization and to at times use excessive force, with the potential for calamitous results for local people, or, in extreme cases, to accomplish regime change by supporting opposition parties in target states. 展开更多
关键词 No-Fly Zone HUMANITARIAN intervention international NORM SOVEREIGNTY
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Effect of Ti-Mg-Ca treatment on properties of heat-affected zone after high heat input welding
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作者 Hao-nan Lou Chao Wang +2 位作者 Bing-xing Wang Zhao-dong Wang R.D.K. Misra 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2019年第5期501-511,共11页
The combined influence of Mg and Ca treatment on the properties of heat-affected zone (HAZ) of low-carbon steel after high heat input welding was systematically studied. Experimental steels deoxidized with different e... The combined influence of Mg and Ca treatment on the properties of heat-affected zone (HAZ) of low-carbon steel after high heat input welding was systematically studied. Experimental steels deoxidized with different elements were prepared, i.e., C-Mn steel with Al, Ti-Ca steel with Ti and Ca, Ti-Mg-Ca steel with Ti, Mg and Ca. Results showed that the inclusions in C-Mn steel were mainly Al2O3 and MnS with low density and large size. However, the average size was refined to only ~0.34 μm in Ti-Mg-Ca steel and the amount increased remarkably. Microstructure of simulated HAZ for 200 kJ/cm changed from ferrite side plates or upper bainite to acicular ferrite after treatment with Ti, Mg and Ca. Ca addition decreased the strain field around inclusions and enhanced the ability of acicular ferrite nucleation. In situ observation of Ti-Mg-Ca steel showed that the movement of austenite grain boundaries was retarded and nucleation sites of acicular ferrite were greater than Ti-Ca steel because of Mg addition. Impact energy of HAZ at — 40℃ was increased from 7 to 232 J and showed excellent stability because of Ti-Mg-Ca treatment. High volume fraction of acicular ferrite acted as obstacles toward cleavage cracks. 展开更多
关键词 Heat-affected ZONE MICROSTRUCTURE STRAIN FIELD Impact energy Ca-Mg TREATMENT
Carbon Reserve Characteristics of Arbor Layer in Mid-subtropical Evergreen Broad-leaved Forest 预览
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作者 Zeng Zhangquan Wang Ying +4 位作者 Li Minghong Tang Hong Yang Rui Zhang Canming Zeng Xiahui 《气象与环境研究:英文版》 CAS 2019年第4期81-83,共3页
In this paper, secondary forest of Pinus massoniana , coniferous-broad-leaved mixed forest and broad-leaved evergreen forest were taken as research objects, to explore carbon reserve of arbor layer and its spatial dis... In this paper, secondary forest of Pinus massoniana , coniferous-broad-leaved mixed forest and broad-leaved evergreen forest were taken as research objects, to explore carbon reserve of arbor layer and its spatial distribution characteristics. At different succession stages, the sequence of organic carbon content in each organ was secondary forest of P. massoniana > coniferous-broad-leaved mixed forest> broad-leaved evergreen forest. Carbon reserve of arbor layer was the highest in broad-leaved evergreen forest, which was 129.34 t/hm 2, followed by coniferous-broad-leaved mixed forest (95.83 t/hm 2), and the minimum was 85.27 t/hm 2 in secondary forest of P. massoniana . In each stand type, the sequence of carbon reserve of each organ in arbor layer was trunk>root>branch>leaf>bark. Carbon reserve of arbor layer mainly concentrated in trunk, and the proportion to carbon reserve of arbor layer declined from secondary forest of P. massoniana to broad-leaved evergreen forest, while it had increasing relationship in root. In secondary forest of P. massoniana , coniferous-broad-leaved mixed forest and broad-leaved evergreen forest, individual with the diameter more than 20 cm accounted for the majority of carbon reserve in the arbor layer. 展开更多
关键词 EVERGREEN broad-leaved forest CARBON RESERVE of ARBOR LAYER Mid-subtropical zone
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Microbial Geochemical Characteristics of the Coalbed Methane in the Shizhuangnan Block of Qinshui Basin,North China and their Geological Implications 预览
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作者 LI Yang SHI Wei TANG Shuheng 《地质学报:英文版》 SCIE CAS CSCD 2019年第3期660-674,共15页
Methanogens and sulfate reducing bacteria were detected by the 16SrRNA sequencing of coalbed methane(CBM)co-produced water in the south of the Qinshui Basin,which is indicative of the presence of secondary biological ... Methanogens and sulfate reducing bacteria were detected by the 16SrRNA sequencing of coalbed methane(CBM)co-produced water in the south of the Qinshui Basin,which is indicative of the presence of secondary biological gas in the south of this basin,in contradiction to the previous understanding of thermogenic gas.This work systematically collected water samples from the CBM wells in the Shizhuangnan Block and analyzed the microbial geochemical characteristics from the aspects of water ions,hydrogen and oxygen isotopes,dissolved inorganic carbon and microbial diversity.It is shown that the Shizhuangnan Block has a nearly SN-trending monoclinic structure,and the elevation of coal seam decreases gradually from the east to west.Because of the water blocking effect of Sitou fault in the west,the precipitation flowed from the east to west,and gradually transited to stagnant flow area.The concentration variation of some ions such as Na^+,K^+,Ca2^+,Mg2^+,Cl^-,HCO3^-and total dissolved solids(TDS)suggest the variation of redox condition in the coal reservoir water.The 16SrDNA sequencing analysis of the collected water samples detected the presence of methanogens and sulfate reduction bacteria.The presence of methane production zone and sulfate methane transition zone(SMTZ)was identified.The effect of methanogens in the methane production zone leads to an increase in the methane concentration,resulting in a high gas content in the study area.In the SMTZ,most methane is consumed by anaerobic oxidation due to high sulfate concentrations. 展开更多
关键词 CBM co-produced water MICROBIAL geochemistry sulfate methane transition zone Shizhuangnan BLOCK
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低频通信系统天线近场辐射危害研究 预览
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作者 王彦碧 《装备环境工程》 CAS 2019年第1期114-117,共4页
目的为低频通信系统电磁辐射危害控制方法提供数据支撑。方法基于IEEE-Std-C95.1—2005、GJB5313A—2017以及GB8702—2014,通过试验详细地获取不同功率和频率条件下低频通信系统天线近场综合场强值,并将工作区域划分为危险区、短时活动... 目的为低频通信系统电磁辐射危害控制方法提供数据支撑。方法基于IEEE-Std-C95.1—2005、GJB5313A—2017以及GB8702—2014,通过试验详细地获取不同功率和频率条件下低频通信系统天线近场综合场强值,并将工作区域划分为危险区、短时活动区和安全工作区。结果以甚低频菱形天线为中心,40m半径范围内为危险区,其峰值场强高于70V/m,40~70m半径范围内为短时活动区,70m半径外为安全工作区。结论甚低频天线近场电磁辐射危害试验验证和区域划分,为低频通信系统电磁辐射危害有效控制提供技术支撑。 展开更多
关键词 低频通信系统 天线近场 辐射危害 区域划分
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Tensile-strain induced phonon splitting in diamond
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作者 蒲梅芳 张峰 +2 位作者 刘珊 入舩徹男 雷力 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第5期71-74,共4页
The first-order Raman spectroscopy of diamond exhibits splitting and redshift after the burst of high-pressure (160– 200 GPa) and high-temperature (-2000 K).The observed longitudinal optical (LO) and the transverse o... The first-order Raman spectroscopy of diamond exhibits splitting and redshift after the burst of high-pressure (160– 200 GPa) and high-temperature (-2000 K).The observed longitudinal optical (LO) and the transverse optical (TO) splitting of Raman phonon is related to the tensile-strain induced activation of the forbidden or silent Raman modes that arise in the proximity of the Brillouin zone center. 展开更多
关键词 DIAMOND tensile-strain PHONON SPLITTING BRILLOUIN ZONE
Intrauterine cystic adenomyosis: Report of two cases 预览
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作者 Yan-Yan Fan Yi-Nan Liu +1 位作者 Jia Li Yan Fu 《世界临床病例杂志》 2019年第5期676-683,共8页
BACKGROUND Cystic adenomyosis is a special type of adenomyosis. Its clinical manifestations lack specificity. Pelvic ultrasound and nuclear magnetic resonance imaging can help clarify the diagnosis. Because cystic ute... BACKGROUND Cystic adenomyosis is a special type of adenomyosis. Its clinical manifestations lack specificity. Pelvic ultrasound and nuclear magnetic resonance imaging can help clarify the diagnosis. Because cystic uterine adenomyosis is rare in clinical work, it can be easily misdiagnosed or its diagnosis can be missed. Early surgical treatment and postoperative drug treatment can alleviate dysmenorrhea, menorrhagia, anemia, and other symptoms. CASE SUMMARY Two cases complained about abnormal vaginal bleeding and were diagnosed with intrauterine cystic adenomyosis by gynecological ultrasound and pathological examination. The clinical manifestations included dysmenorrhea, hypermenorrhea, and a history of cesarean section. Both cases underwent a surgery, and chocolate-like liquid was released from the cystic mass in the uterus and the manifestations were relieved. CONCLUSION Intrauterine cystic adenomyosis could be diagnosed by pathological examination and treated by hysterectomy or hystscopy to release the liquid inside. 展开更多
关键词 CYSTIC ADENOMYOSIS ADENOMYOSIS JUNCTIONAL ZONE INTRAUTERINE Case REPORT
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Teda Suez, a Cooperation Model under the Belt and Road Initiative 预览
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作者 LI JUN 《今日中国:英文版》 2019年第7期48-50,共3页
THE China-Egypt Teda Suez Economic and Trade Cooperation Zone, or simply Teda Cooperation Zone, is located in Sokhna District of Suez Province, more than 120 kilometers away from Cairo, the capital of Egypt. It is amo... THE China-Egypt Teda Suez Economic and Trade Cooperation Zone, or simply Teda Cooperation Zone, is located in Sokhna District of Suez Province, more than 120 kilometers away from Cairo, the capital of Egypt. It is among the second batch of state-level overseas economic and trade cooperation zones approved by the Chinese government. Signboards bearing the phrase “A sign of development” can be seen everywhere in the park, marking the original intention of setting up this economic and trade cooperation zone. 展开更多
关键词 China-Egypt Suez ECONOMIC TRADE cooperation zone
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