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Application Effects of Ultra-fine Powder Shaped Maize Seed Coating Agent in Spring Sowing areas in northeast China 被引量:1
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作者 孙成韬 张小祥 《Agricultural Science & Technology》 CAS 2015年第10期2104-2106,共3页
The research explored adaptability maize seed coating agent in spring sowing and effects of ultra-fine powder shaped areas in northeast China. The results showed that germination potential and rate both improved aroun... The research explored adaptability maize seed coating agent in spring sowing and effects of ultra-fine powder shaped areas in northeast China. The results showed that germination potential and rate both improved around 5% and the num- ber of root increased by 4% in the treatments with ultra-fine powder shaped maize seed coating agent compared with the control group without seed coating. What's more, the treatments with ultra-fine powder shaped maize seed coating agent took advantages in terms of fresh weight of seeding, stem diameter, and dry weight. It is notable that control effects on underground insects performed the best, with per- centage over 94%, which is more excellent relative to other agents in markets. Therefore, ultra-fine powder shaped maize seed coating agent can be widely applied in spring sowing areas in northeast China, without side effects. 展开更多
关键词 MAIZE Utra-fine powder Seed-coating agent Germination potential YIELD Spring sowing area Application effect
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Geostress measurements near fault areas using borehole stress-relief method 被引量:5
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作者 黄明清 吴爱祥 +1 位作者 王贻明 韩斌 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3660-3665,共6页
To minimize negative effects of geostress distribution on mining safety near the fault areas, the UPM40 triaxial geostress testing system was introduced to conduct in-situ geostress measurements at three sites and nin... To minimize negative effects of geostress distribution on mining safety near the fault areas, the UPM40 triaxial geostress testing system was introduced to conduct in-situ geostress measurements at three sites and nine points by the borehole stress-relief method. The results of strain?confining pressure curves show that rock masses at the three measuring sites exhibit comprehensive linear elasticity in spite of various fissures or cracks within rocks. Horizontal and vertical stress components distribute discrepantly near the fault areas, and the maximum lateral pressure coefficient is as high as 6.15. The maximum principle stress ranges from 8.01 to 14.93 MPa, and stress directions are in the range of N78.07°W?N17.55°W. Geostresses near fault areas are dominated by the horizontal tectonic stresses, while the lower values, compared to those under similar geological conditions are due to stress release by the fault. Additionally, the fault and shear stress nearby are partially responsible for asymmetric elongation and southwesterly migration of orebodies. 展开更多
关键词 fault areas geostress distribution borehole stress-relief method lateral pressure coefficient horizontal tectonic stress
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Synthesis Scheme for Low Power Designs Under Timing Constraints 被引量:5
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作者 王玲 温东新 +1 位作者 杨孝宗 蒋颖涛 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第2期287-293,共7页
To minimize the power consumption with resources operating at multiple voltages a time-constrained algorithm is presented.The input to the scheme is an unscheduled data flow graph (DFG),and timing or resource constrai... To minimize the power consumption with resources operating at multiple voltages a time-constrained algorithm is presented.The input to the scheme is an unscheduled data flow graph (DFG),and timing or resource constraints.Partitioning is considered with scheduling in the proposed algorithm as multiple voltage design can lead to an increase in interconnection complexity at layout level.That is,in the proposed algorithm power consumption is first reduced by the scheduling step,and then the partitioning step takes over to decrease the interconnection complexity.The time-constrained algorithm has time complexity of O(n 2),where n is the number of nodes in the DFG.Experiments with a number of DSP benchmarks show that the proposed algorithm achieves the power reduction under timing constraints by an average of 46 5%. 展开更多
关键词 low power multiple supply voltages partitioning timing constraints SCHEDULING
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Analysis on Chemical Compositions in Chinese Wolfberry from Different Producing Areas 被引量:4
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作者 董海峰 任永丽 《Agricultural Science & Technology》 CAS 2012年第9期1870-1872,共3页
[Objective] This study aimed to conduct correspondence cluster analysis of the trace elements in Chinese wolfberry from Qinghai and Ningxia regions, and to investigate the relationship among the quality of the wolfber... [Objective] This study aimed to conduct correspondence cluster analysis of the trace elements in Chinese wolfberry from Qinghai and Ningxia regions, and to investigate the relationship among the quality of the wolfberry samples, the composition of trace elements and the sample sources. [Method] The determined contents of trace elements and ratios of zinc to copper (Zn/Cu) of wolfberry from 11 different producing areas of Qinghai and Ningxia regions were adopted to construct the raw measurement data matrix, to analyze the distribution characteristics of the trace ele- ments in wolfberry from Qinghai and Ningxia by using the corresponding cluster analysis method. [Result] The quality of wolfberry samples in 7hongning County, Zhongwei City, Pingluo County, Shizuishan City, Heicheng Town of Ningxia Hui Au-tonomous Region and Hehuang Valley, Golmud City of Qinghai Province is mainly related to the contents of Zn and Mn; Zn/Cu greatly affects the quality of Chinese wolfberry in Dulan County of Qinghai Province; Fe has great effect on the quality of Chinese wolfberry in Yinchuan City of Ningxia Hui Autonomous Region; Cu greatly affects the quality of Chinese wolfberry in Nuomuhong Village of Qinghai Province and a wolfberry research institute in Ningxia. [Conclusion] The relationship between the quality of wolfberry from different producing areas and the trace elements was investigated, which provides theoretical and practical basis for the cultivation, har- vesting, processing, and further development and utilization of Chinese wolfberry resources from different producing areas. 展开更多
关键词 Chinese wolfberry Correspondence cluster analysis Trace elements
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Effect of stress on microstructures of creep-aged 2524 alloy 被引量:3
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作者 权力伟 赵刚 +1 位作者 田妮 黄明丽 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第8期2209-2214,共6页
Microstructures of creep-aged 2524 (A1-4.3Cu-1.5Mg) aged at 170 ℃ with various stresses (0, 173 and 250 MPa) were studied on a creep machine. Ageing hardness curves under various stresses were plotted and the cor... Microstructures of creep-aged 2524 (A1-4.3Cu-1.5Mg) aged at 170 ℃ with various stresses (0, 173 and 250 MPa) were studied on a creep machine. Ageing hardness curves under various stresses were plotted and the corresponding microstructures were characterized by transmission electron microscopy (TEM). The results show that the value of peak hardness is increased, while the time to reach the peak hardness is reduced under an external stress. Meanwhile, the length of S(Al2CuMg) phase is shorter and the number density of S phases is larger in the creep-aged alloy. The predominant contribution to the peak hardness can be ascribed to the GPB zones with an elastic stress. 展开更多
关键词 creep-age S phase GPB zone hardness DISLOCATION stress orientation effect
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Soil vanadium pollution and microbial response characteristics from stone coal smelting district 被引量:8
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作者 肖细元 杨淼 +3 位作者 郭朝晖 姜智超 刘亚男 曹霞 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第4期1271-1278,共8页
A field investigation was performed to study the content, speciation and mobility of vanadium, as well as microbial response in soil from a stone coal smelting district in Hunan province of China. The results showed t... A field investigation was performed to study the content, speciation and mobility of vanadium, as well as microbial response in soil from a stone coal smelting district in Hunan province of China. The results showed that the contents of soil V ranged from 168 to 1538 mg/kg, which exceeded the maximum permissible value of Canadian soil quality for V. The mean soil V content from wasteland area reached 1421 mg/kg, and those from the areas related with slag heap, ore pile and smelting center were 380, 260 and 225 mg/kg, respectively. Based on the results of the modified BCR sequential extraction procedure, V contents in the mobile fractions varied from 19.2 to 637 mg/kg accounting for 7.4%-42.3% of total V, and those of V(+5) species were between 21.9 and 534.0 mg/kg. Soil enzyme activity and microbial basal respiration were adversely affected by high level of soil V. More attention should be paid to soil V pollution and potential hazardous surrounding the stone coal smelting district. 展开更多
关键词 VANADIUM soil pollution MOBILITY microbial response stone coal smelting district
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EFFECT OF LOCAL HARD ZONE ONFRACTURE INITIATION OF WELD HAZ
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作者 荆洪阳 霍立兴 +2 位作者 张玉凤 丰田政南 南二三吉 《Transactions of Tianjin University》 EI CAS 1995年第1期37+31-36,共7页
The effect of the local hard zone (LHZ) distributed in the coarse grained HAZ (CGHAZ) has been analyzed by 2-dimensional FEM on a mechanical model of the weld CGHAZ. The existence of the LHZ elevates considerably the ... The effect of the local hard zone (LHZ) distributed in the coarse grained HAZ (CGHAZ) has been analyzed by 2-dimensional FEM on a mechanical model of the weld CGHAZ. The existence of the LHZ elevates considerably the stress in LHZ and causes the discontinuity of strain at the boundary between the LHZ and the matrix. The stress distribution in the LHZ is strongly affected by the shape of the LHZ. In a slender LHZ almost the whole region in the LHZ is exposed to elevated stress, whereas in the massive LHZ only the edge region sustains high stress. The longer the LHZ becomes, the more the highly stressed area, and the peak stress in the LHZ grows even under the same volume fraction of the LHZ. These results indicate that the slender LHZ brings about unstable fracture at a lower load level than the blocky LHZ. This tendency was confirmed by CTOD test results on the weld CGHAZ of a high-strength steel. The CGHAZ with elongated M-A constituents fractures at apparently lower critical CTOD than the CGHAZ with massive M-A constituents. In conclusion, the control of the shape of the M-A constituent has a striking effect on the toughness improvement of CGHAZ. 展开更多
关键词 coarse grained HAZ local hard zone STRESS M-A constituent
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Comparison of the time-domain electromagnetic field from an infinitesimal point charge and dipole source 被引量:3
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作者 周楠楠 薛国强 王贺元 《Applied Geophysics》 SCIE CSCD 2013年第3期349-356,359,共9页
An electromagnetic field is generated through the accelerating movement of two equal but opposite charges of a single dipole. An electromagnetic field can also be generated by a time-varying infinitesimal point charge... An electromagnetic field is generated through the accelerating movement of two equal but opposite charges of a single dipole. An electromagnetic field can also be generated by a time-varying infinitesimal point charge. In this study, a comparison between the electromagnetic fields of an infinitesimal point charge and a dipole has been presented. First, the time-domain potential function of a point source in a 3D conductive medium is derived. Then the electric and magnetic fields in a 3D homogeneous lossless space are derived via the relation between the potential and field. The field differences between the infinitesimal point charge and the dipole in the step-off time, far-source, and near-source zones are analyzed, and the accuracy of the solutions from these sources is investigated. It is also shown that the field of the infinitesimal point charge in the near-source zone is different from that of the dipole, whereas the far-source zone fields of these two sources are identical. The comparison of real and simulated data shows that the infinitesimal point charge represents the real source better than the divole source. 展开更多
关键词 Infinitesimal point charge dipole source TIME-DOMAIN electromagnetic response near-source zone.
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The launch of a large regional gravity information system in China 被引量:1
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作者 张明华 贺颢 王成锡 《Applied Geophysics》 SCIE CSCD 2011年第2期170-175,179,共7页
We developed the China Regional Gravity Information System(RGIS) using mixed language programming in Visual Basic,Visual C++,and FORTRAN.The software is based on the MapInfo platform with OLE technology.With this ... We developed the China Regional Gravity Information System(RGIS) using mixed language programming in Visual Basic,Visual C++,and FORTRAN.The software is based on the MapInfo platform with OLE technology.With this system,we achieve visual data management for the database with spatial geography,geology data and gravity data as well as graphical data editing and data table operations over the whole of China.We are able to perform normalized gravity reduction,gravity and magnetic field transforms,gravity anomaly inversion and interpretation,thematic mapping and so on. 展开更多
关键词 RGIS gravity database GIS application potential data processing
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Impacts and Countermeasures of Climate Change on Animal Husbandry in Qinghai Plateau and Its Surrounding Area 被引量:8
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作者 李红梅 李林 +1 位作者 邓振镛 黎明 《Agricultural Science & Technology》 CAS 2010年第7期138-144,共7页
The paper aims to study the impacts and countermeasures of climate change on animal husbandry in Qinghai plateau and its surrounding area,and evaluate the effect of countermeasures.Results showed that:First,the annua... The paper aims to study the impacts and countermeasures of climate change on animal husbandry in Qinghai plateau and its surrounding area,and evaluate the effect of countermeasures.Results showed that:First,the annual mean temperature,annual mean maximum temperature and annual mean minimum temperature showed an increasing trend in Qinghai plateau during the time from 1961 to 2008; the annual precipitation had not obvious change,but the obvious feature of seasonal change; wind speed and sunshine hours showed a decreasing trend during the time from 1961 to 2008.Secondly,under the current climate condition,grassland productivity showed a decreasing trend,and the grassland theoretical capacity affected by grassland productivity decreased too; warm winter was in favor of livestock overwintering safely,which resulted in a high level of the survival rate of young stock; temperature increasing and precipitation decreasing were beneficial to the fatness of livestock,but the meat yield of livestock was affected by some negative factors such as grassland degradation; livestock diseases had a close relationship with weather condition,and adverse weather condition may arose many diseases of livestock.Thirdly,in view of the current problems of livestock production,we took a series of countermeasures including grass industry construction,livestock improvement,developing new modes of animal husbandry,control and prevention of stockbreeding diseases and insect pests and recovery of meteorological disasters,which played a important role in promoting grassland productivity,solving the problem of the imbalances between livestock and forage,protecting the ecological environment and improving livestock performance. 展开更多
关键词 Climate change Qinghai plateau and its surrounding area Animal Husbandry Impact COUNTERMEASURES
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Controlling effects of forest belts on non-point source pollution of agricultural lands in Taihu Lake area, China 被引量:1
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作者 陈金林 侍璐璐 张爱国 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期213-216,251,共4页
Taihu Lake area is one of the most developed areas in agricultural production. Application of fertilizers and pesticides in large quantities greatly aggravate environmental pollution of this area, and water pollution ... Taihu Lake area is one of the most developed areas in agricultural production. Application of fertilizers and pesticides in large quantities greatly aggravate environmental pollution of this area, and water pollution has worsened to an unbearable condition. Two sampling farms (respectively 1 hm2) under rape-rice rotation and wheat-rice rotation were selected as studied ecosystem and a 5-yr-old Poplar forest and 8-yr-old Metasequoia forest were chosen in the selected areas. By collecting samples of Nitrogen, Phosphorus in water, crops and underground of forest, the transfer and loss of N and P (main water pollutants) in faming ecosystem were studied, and the effects of forest belts on non-point source pollution of agricultural lands was analyzed. The results indicated that the transfer and loss of N and P vary with means of rotation, types of crops and the amount of fertilizer application. Buffering forest belts betweens farmlands and ditches can effectively stop and purify such elements as N and P in soil runoffs, thus controlling non-point source pollution of agricultural lands. When the width ratio of farmland to forest belt is 100 to 40, 50.05% losing N, 29.37% losing P can be absorbed by forest under rape-rice rotation and 30.98% N, 86.73% P can be absorbed by forest under wheat-rice rotation. When the width ratio of farmland to forest belt is 150 to 40, 33.37% losing N, 19.58% losing P can be absorbed by the forest under rape-rice rotation, and under wheat-rice rotation 20.65% lost N and 57.82% lost P can be absorbed. There is only some purification effect when the width ration of farmland to forest belt is 200 to 40. Based on model of buffering forest belts, the width ratio of farmland to forest is determined between 100 to 40 and 150 to 40, because it not only can purify water, but also occupy less farmland. It is suggested that Poplars, with the characteristics of fast-growing and high value, are suitable to be planted as shelter-forest in Taihu Lake Watershed. 展开更多
关键词 AGRICULTURE Non-point source pollution Ultrophication NITROGEN PHOSPHORUS Forest belt Sustainable development
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Channel Lateral Pocket or Halo Region of NMOSFET Characterized by Interface State R G Current of the Forward Gated Diode
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作者 何进 黄爱华 +1 位作者 张兴 黄如 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第7期826-831,共6页
The channel lateral pocket or halo region of NMOSFET characterized by interface state R G current of a forward gated diode has been investigated numerically for the first time.The result of numerical analysis demons... The channel lateral pocket or halo region of NMOSFET characterized by interface state R G current of a forward gated diode has been investigated numerically for the first time.The result of numerical analysis demonstrates that the effective surface doping concentration and the interface state density of the pocket or halo region are interface states R G current peak position dependent and amplitude dependent,respectively.It can be expressed quantitatively according to the device physics knowledge,thus,the direct characterization of the interface state density and the effective surface doping concentration of the pocket or halo becomes very easy. 展开更多
关键词 forward gated diode R G current MOSFET pocket or halo implant region interface states effective surface doping concentration
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Sugarcane Requirement of Water and Effect of Fertigation on Sugarcane 被引量:1
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作者 谭宏伟 周柳强 +1 位作者 谢如林 黄美福 《Agricultural Science & Technology》 CAS 2009年第4期175-177,182,共4页
The sugarcane is a main sugar crop in China. The seasonal drying is one of the problems that influence the improvement of output and quality of sugarcane in China. The experimental results for the water requirement an... The sugarcane is a main sugar crop in China. The seasonal drying is one of the problems that influence the improvement of output and quality of sugarcane in China. The experimental results for the water requirement and fertigation of the sugarcane showed, that the distribution of the rainfall in spring, autumn and winter, all could not suit the requirements for sugarcane growth. Detailedly, it can suit that sugarcane requirement of 74.4%, 68.6% and 35.7% respectively at seedling emerging stage, tillering stage and mature stage according to sugarcane growth. The drought has already limited the yield of sugarcane. Application of fertigation can enhance the fertilizer use efficiency, and it is also a water saving technique in sugarcane production. 展开更多
关键词 Sugarcane planting area Distribution of rainfall Water requirement of sugarcane FERTIGATION
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Study on the Introduction of Plants with Colored Foliage in Zhengzhou Area and Their Adaptability 被引量:4
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作者 王慧娟 孟月娥 +2 位作者 赵秀山 王利民 李艳敏 《Agricultural Science & Technology》 CAS 2013年第2期279-285,375,共8页
[Objective] This study aimed to preliminarily select the plants with colored foliage adaptable to Zhengzhou area. [Method] An introduction trial on 42 varieties with colored foliage was conducted, in which major ornam... [Objective] This study aimed to preliminarily select the plants with colored foliage adaptable to Zhengzhou area. [Method] An introduction trial on 42 varieties with colored foliage was conducted, in which major ornamental characteristics, phenological phases and stress resistance of all the introduced plants with colored foliage were observed and the introduced plants were comprehensively evaluated. [Result] Golden-and Compound-leaved Maple, Red-leaved Sakura, Pink-and Compound-leaved Maple, Amur Maple, Purple-leaved Canadian Redbud with good performance were selected preliminarily, which can be applied for landscape in Zhengzhou area. Among them, Golden- and Compound-leaved Maple, Golden- and Silvery-leaved Maple and Purple-leaved Smoketree can either be planted separately, or in a line as boulevard trees, or in groups as ornamental forest; Red-leaved Sakura, Pink- and Compound-leaved Maple and Purple-leaved Canadian Redbud can be planted in groups or separately in gardens, parks or alongside streets or in front of buildings; Amur Maple with high adaptability is a excellent tree species for afforesting barren mountain. [Conclusion] This study has not only provided new excellent germplasm sources for the landscaping in Zhengzhou area, thus favoring the improvement of local landscaping level, but also provides examples and references for the introduction of plants with colored foliage in the other areas. 展开更多
关键词 Zhengzhou area Introduction trial Plants with colored foliage ADAPTABILITY
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Recent Requirements and Future Development of Integrated EMS/DTS System in China 被引量:1
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作者 张伯明 孙宏斌 吴文传 《Electricity》 2001年第2期20-24,共5页
Resent status for dispatch automation systems in China is introduced and the requirement for integrated EMS/DTS is discussed. The advantages of the integration of EMS/DTS are analyzed. Large benefit can be obtained to... Resent status for dispatch automation systems in China is introduced and the requirement for integrated EMS/DTS is discussed. The advantages of the integration of EMS/DTS are analyzed. Large benefit can be obtained to develop an integrated EMS/DTS system. EMS/DTS functions for district power system application are investigated and introduced. An application of the LINUX based EMS/DTS to Yulin power system is reported and is used to show the advantage of an open system. Future development of integrated EMS/DTS systems in China is discussed. 展开更多
关键词 EMS/DTS integrated system district power system LINUX application
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Application of Wild Plant Resources of Qin-ba Mountainous Area for Vertical vrescence in Landscape Architecture 被引量:3
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作者 袁海龙 《Journal of Landscape Research》 2010年第2期51-54,共4页
Based on introducing wild plant resources of vertical greening in Qin-ba Mountainous area, the application of vertical greening plants of Qin-ba Mountainous area in garden greening were analyzed, the measures of utili... Based on introducing wild plant resources of vertical greening in Qin-ba Mountainous area, the application of vertical greening plants of Qin-ba Mountainous area in garden greening were analyzed, the measures of utilization and development were suggested. 展开更多
关键词 Qin-ba mountainous area PLANT Vertical greening Landscape application
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'水十条'大考渐行渐近四要素成后续治理重头戏
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作者 中国环保在线编辑部 《区域治理》 2018年第1期1-1,共1页
'水十条'提出,2017年年底前,工业集聚区应按规定建成污水集中处理设施并安装自动在线监控装置.环保部水环境管理司相关负责人表示:'下一步我们将继续强化对各地整改工作的督促指导.推动并逐步形成省级及以上工业集聚区'... '水十条'提出,2017年年底前,工业集聚区应按规定建成污水集中处理设施并安装自动在线监控装置.环保部水环境管理司相关负责人表示:'下一步我们将继续强化对各地整改工作的督促指导.推动并逐步形成省级及以上工业集聚区'一园一档',并实现信息化,动态更新数据.' 据环境保护部宣传教育司微博消息,环保部水环境管理司相关负责人今日指出,对于《水十条》规定的各项硬任务都必须不折不扣的落实,考核认定工作也同样如此,不打折扣,谁打折扣甚至弄虚作假,一经发现就要严肃追责. 展开更多
关键词 环境 教育司 环保部 管理司 区应 工作 硬任务 装置
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Analysis of Short-term Heavy Precipitations in a Regional Heavy Rainstorm in Shannxi Province
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作者 王楠 《Agricultural Science & Technology》 CAS 2013年第3期411-416,共6页
[Objective] This study aimed to analyze the cause of the generation of short-term heavy precipitations in a regional heavy rainstorm in Shannxi Province. [Method] Taking a heavy rainstorm covering most parts of Shaanx... [Objective] This study aimed to analyze the cause of the generation of short-term heavy precipitations in a regional heavy rainstorm in Shannxi Province. [Method] Taking a heavy rainstorm covering most parts of Shaanxi Province in late July 2010 as an example, data of five Doppler weather radars in Shaanxi Province were employed for a detailed analysis of the evolution of the heavy rainstorm pro- cess. [Result] Besides the good large-scale weather background conditions, the de- velopment and evolution of some mesoscale and small-scale weather systems direct- ly led to short-term heavy precipitations during the heavy rainstorm process, involv- ing the intrusion of moderate IS-scale weak cold air and presence of small-scale wind shear, convergence and adverse wind area. In addition, small-scale convection echoes were arranged in lines and formed a "train effect", which would also con- tribute to the generation of short-term heavy precipitation. [Conclusion] This study provided basic information for more clear and in-depth analysis of the formation mechanism of short-term heavy precipitations. 展开更多
关键词 Short-term heavy precipitation Doppler weather radar Adverse wind area: Train effect
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Impact of Dry Warming on Economic and Characteristic Crop and Coping Technology in Northwest of China 被引量:4
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作者 邓振镛 倾继祖 +3 位作者 杨启国 宁惠芳 黄蕾诺 徐金强 《Agricultural Science & Technology》 CAS 2010年第4期124-129,共6页
Based on the state of characteristics of dry warming of modern climate changing,the response of growth,output and quality of main economic crops such as cotton,flax and winter rape and characteristic crop such as vini... Based on the state of characteristics of dry warming of modern climate changing,the response of growth,output and quality of main economic crops such as cotton,flax and winter rape and characteristic crop such as vinifera and apple were discussed.The coping technology for climate changing and measurements for serving the agricultural were provided. 展开更多
关键词 NORTHWEST Dry warming Economic crop Characteristic crop Influence Coping technology
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Physiological Adaptation of Habitat by Ion Distribution in the Leaves of Four Ecotypes of Reed (Phragmites australis) 被引量:9
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作者 郑文菊 陈国仓 +3 位作者 张承烈 胡玉熹 李凌浩 林金星 《Acta Botanica Sinica》 CSCD 2002年第1期82-87,共6页
The ion levels in the epidermal bulliform cells of epidermis, mesophyll cells and cells of the vascular bundle sheath of four ecotypes of reed (Phragmites australis (Cav.) Trin. ex Steud.) were determined by means of ... The ion levels in the epidermal bulliform cells of epidermis, mesophyll cells and cells of the vascular bundle sheath of four ecotypes of reed (Phragmites australis (Cav.) Trin. ex Steud.) were determined by means of X_ray microanalysis. The results indicated that higher K +, Na +, Ca 2+ , Mg 2+ and Cl - were distributed in the vascular bundle sheath cells than in mesophyll cells and epidermal bulliform cells of the swamp ecotype. Higher Ca 2+ was found in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, higher Mg 2+ in the mesophyll cells and higher K +, Na + and Cl - in the vascular bundle sheath cells of the dune ecotype. Higher Na + and Mg 2+ was determined in the mesophyll cells than in the bulliform cells and vascular bundle sheath cells, and higher K +, Ca 2+ and Cl - in the vascular bundle sheath cells of the light salt meadow ecotype. In the heavy salt meadow ecotype, higher Na + and Mg 2+ were accumulated in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, but higher K +, Ca 2+ and Cl - in the mesophyll cells. Furthermore, the distributional conditions of the above five ions in leaf cells of the four ecotypes and their significance in the physiological adaptation of reed to habitat were discussed in detail. 展开更多
关键词 reed ( Phragmites australis ) ion distribution physiological adaptation ECOTYPES X_ray micro_analysis
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