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Simulation of the Accumulation Process of Biogenic Gas Hydrates in the Shenhu Area of Northern South China Sea 被引量:3
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作者 LIAO Jing GONG Jianming +4 位作者 Lü Wanjun WU Nengyou YUE Baojing LUAN Xiwu HU Gaowei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第6期2285-2286,共2页
Previous work has largely discussed the relations between sediment structures and accumulation of gas hydrates in the Shenhu area of South China Sea, but has not documented why the gas hydrates occurred at the seafloo... Previous work has largely discussed the relations between sediment structures and accumulation of gas hydrates in the Shenhu area of South China Sea, but has not documented why the gas hydrates occurred at the seafloor topographic highs. Many gas hydrate exploration examples abroad also indicate that the saturation of gas hydrates was higher at seafloor topographic highs. This work aims to understand why gas hydrates accumulated at topographic highs and why their saturation is higher. 展开更多
关键词 area Simulation of the Accumulation process of Biogenic Gas Hydrates in the Shenhu area of Northern South China Sea THAN
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Analysis on the Heavy Snow Weather Process in Benxi Area 被引量:1
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作者 KOU Si-cong CAO Wen 《Meteorological and Environmental Research》 CAS 2011年第1期24-27,共4页
[Objective] The aim was to study the formation and development of a heavy snow in Benxi area. [Method] Based on conventional meteorological data, the formation and development of a heavy snow in Benxi area from Decemb... [Objective] The aim was to study the formation and development of a heavy snow in Benxi area. [Method] Based on conventional meteorological data, the formation and development of a heavy snow in Benxi area from December 4th to 5th in 2009 were analyzed from the aspects of weather situation evolution and physical quantity field feature. [Result] The heavy snow was caused by upper trough and North China cyclone. In this process, there was upper level divergence and lower level convergence over Benxi area, and it was warm at low attitude and cold at high attitude; southwest jet at low attitude transported water vapor from Bohai Sea to eastern Liaoning, which provided good water vapor condition for snow, but it didn’t reach heavy snow due to inadequate ascending force. The development of Ural Mountains high ridge played an important role in the snow process and the strengthened high ridge moving northward was beneficial to the southward movement of cold air and deepening of upper trough. Analysis on physical quantity field could provide reference for predicting beginning and ending time and strength of heavy snow. [Conclusion] The study could provide basis for the forecast of heavy snow. 展开更多
关键词 Heavy snow Weather situation Physical quantity process analysis Benxi area China
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Evaluation of Rainwater Harvesting Methods and Structures Using Analytical Hierarchy Process for a Large Scale Industrial Area 被引量:1
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作者 V. JOTHIPRAKASH Mandar V. SATHE 《Journal of Water Resource and Protection》 2009年第6期427-438,共12页
In India, with ever increasing population and stress on natural resources, especially water, rejuvenation of rainwater harvesting (RWH) technique which was forgotten over the days is becoming very essential. Large num... In India, with ever increasing population and stress on natural resources, especially water, rejuvenation of rainwater harvesting (RWH) technique which was forgotten over the days is becoming very essential. Large number of RWH methods that are available in the literature are demand specific and site specific, since RWH system depends on the topography, land use, land cover, rainfall and demand pattern. Thus for each and every case, a detailed evaluation of RWH structures is required for implementation, including the analy-sis of hydrology, topography and other aspects like site availability and economics, however a common methodology could be evolved. The present study was aimed at evaluation of various RWH techniques in order to identify the most appropriate technique suitable for a large scale industrial area to meet its daily wa-ter demand. An attempt is made to determine the volume of water to be stored using mass balance method, Ripple diagram method, analytical method, and sequent peak algorithm method. Based on various satisfying criteria, analytical hierarchy process (AHP) is employed to determine the most appropriate type of RWH method and required number of RWH structures in the study area. If economy alone is considered along with hydrological and site specific parameters, recharging the aquifer has resulted as a better choice. However other criteria namely risk, satisfaction in obtaining required volume of water for immediate utilization etc. has resulted in opting for concrete storage structures method. From the results it is found that AHP, if used with all possible criteria can result in a better tool for evaluation of RWH methods and structures. This RWH structures not only meets the demand but saves transportation cost of water and reduces the dependability of the industry on irrigation reservoir. Besides monetary benefits it is hoped that the micro environment inside the industry will improve due to the cooling effect of the stored water. 展开更多
关键词 RAIN Water HARVESTING ANALYTICAL HIERARCHY process Large SCALE Industrial area AQUIFER
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A Study on Law of Change of Real Contact Area of Friction during Transition Process
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作者 金长善 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第1期7-10,共4页
Mechanism of frictional vibration and the difference of kinctic-static friction is an open question. Research shows that the change of real area of contact during transition process of friction results in the phenomen... Mechanism of frictional vibration and the difference of kinctic-static friction is an open question. Research shows that the change of real area of contact during transition process of friction results in the phenomena mentioned above. In substance, the F-Vr, descent and F-T ascent characters are caused by A-Vr, and A-T characters respectively. Based on ultrasonic experiment the mechanism of the phenomena is explained and the frictional formulas using the parameter-real area of contact are given in this article. 展开更多
关键词 ss: TRANSITION process FRICTION REAL area of CONTACT
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Study on Winter Operation Process of the Surface Flow Constructed Wetland in Tianjin Area
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作者 Xiaodan Qin Yichao Sun +5 位作者 Li Li Xiaolong Shao Dan Yu Qiongqiong Liu Honglei Liu Lin Han 《Meteorological and Environmental Research》 CAS 2013年第7期43-46,共4页
[Objective] The research aimed to study winter operation process of the surface flow constructed wetland in "rianjin area. [Method] In view of climate characteristics in Tianjin, by the way of running under the ice, ... [Objective] The research aimed to study winter operation process of the surface flow constructed wetland in "rianjin area. [Method] In view of climate characteristics in Tianjin, by the way of running under the ice, winter operation experiment of the surface flow constructed wetland in Tianjin was conducted, with the expectation to get some useful process parameters to run such systems in North China in winter. [ Result] Although purification effect of the sewage by surface flow constructed wetland in winter was worse than that in other seasons ( average reduction of about 20%), surface flow constructed wetland running under the ice was feasible in Tianjin area. When surface flow constructed wetland in North China ran under ice in winter, it was suggested that the outlet must be located in a low position to prevent to be completely frozen, and running water depth should not be less than 50 -60 cm. The hydraulic load could be raised on the basis of reflux, and hydraulic retention time should maintain less than 4 d to keep water-soil interface not freezing. Inlet water depth should be increased as much as possible to improve temperature in the system. V Conclusion1 The research could provide reference for promotion and application of the surface flow constructed wetland in North China. 展开更多
关键词 Surface flow constructed wetland Operation process WINTER Tianjin area China
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Hydrocarbon Accumulation Process in the Marine Strata in Jianghan Plain Area, Middle China
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作者 XU Guosheng ZHANG Lijun +4 位作者 GONG Deyu WANG Guozhi YUAN Haifeng LI Changhong HU Xiaofeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第3期878-893,共16页
Marine strata in the Jianghan Plain area are widely distributed with a total depth of more than 8,000 m from the Upper Sinian to the Middle Triassic. Six reservoir caprock units, named Z-C2, C2-O, S, D--C, P and T1, c... Marine strata in the Jianghan Plain area are widely distributed with a total depth of more than 8,000 m from the Upper Sinian to the Middle Triassic. Six reservoir caprock units, named Z-C2, C2-O, S, D--C, P and T1, can be identified with each epoch. The geology, stratigraphy, drilling, oil testing and other basic data as well as the measured inclusion and strontium isotope data in the study area are used in the analysis of the formation and evolution process of marine petroliferous reservoirs in the Jianghan Plain area. This study aims to provide a scientific basis for the further exploration of hydrocarbons in the Jianghan Plain and reduce the risks by analyzing the key factors for hydrocarbon accumulation in the marine strata. Our findings show that in the Lower Palaeozoic hydrocarbon reservoir, oil/gas migration and accumulation chiefly occurred in the early period of the Early Yanshanian, and the hydrocarbon reservoir was destroyed in the middle-late period of the Early Yanshanian. In the Lower Triassic-Carboniferous hydrocarbon reservoir, oil/gas migration and accumulation chiefly occurred in the Early Yanshanian, and the hydrocarbon reservoir suffered destruction from the Late Yanshanian to the Early Himalayanian. The preservation conditions of the marine strata in the Jianghan Plain area have been improved since the Late Himalayanian. However, because all source beds have missed the oil/gas generation fastigium and lost the capacity to generate secondary hydrocarbon, no reaccumulation of hydrocarbons can be detected in the study area's marine strata. No industrially exploitable oil/gas reservoir has been discovered in the marine strata of Jianghan Plain area since exploration began in 1958. This study confirms that petroliferous reservoirs in the marine strata have been completely destroyed, and that poor preservation conditions are the primary factor leading to unsuccessful hydrocarbon exploration. It is safely concluded that hydrocarbon exploration in the marine strata of the study area is quite risky. 展开更多
关键词 marine strata reservoir caprock unithydrocarbon accumulation process reservoirevolution Jianghan Plain area Middle China
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Modeling of Deposition Process of Particulate Organic Matter (POM) with Sand on Vegetated Area in a River
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作者 Makiko Obana Ho-Seong Jeon Tetsuro Tsujimoto 《Journal of Water Resource and Protection》 2014年第14期1290-1296,共7页
The transport and deposition of particulate organic matter (POM) in river streams has recently received much attention as one of important ecological processes in rivers. We focused on interacted behaviors of sand par... The transport and deposition of particulate organic matter (POM) in river streams has recently received much attention as one of important ecological processes in rivers. We focused on interacted behaviors of sand particles in bed load and POM in vegetated area on sand bars. The purpose of this study is to clarify the characteristics of deposition of POM with bed load on sandbars with the riparian vegetation. A basic experiment on POM transport and deposition with vegetation is conducted in a laboratory flume. It demonstrates that several issues still remain to be future investigated. In particular, the shear due to the bed roughness in the vegetated area and the transport and deposition process of sand particles and POM are required to be described by the proper modeling which will be introduced into a simulation model of various fluvial processes. The main results of this study are that ripples are formed by bed load in riparian vegetation and POM deposition is promoted by ripple behavior. Based on these results, the POM deposition with ripples in vegetated area is described by a conceptual model which will affect various aspects in ecosystem management based on fluvial processes. 展开更多
关键词 Modeling DEPOSITION process PARTICULATE ORGANIC MATTER (POM) SAND Vegetated area
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Analysis of Coverage and Area Spectrum Efficiency of UDN with Inter-Tier Dependence 被引量:1
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作者 Kaichuang Wang Pei Li +3 位作者 Fei Ding Zhiwen Pan Nan Liu Xiaohu You 《China Communications》 SCIE CSCD 2019年第3期154-164,共11页
Stochastic geometry is widely employed to model cellular network. But in most existing works, base stations(BSs) are modelled following a homogeneous Poisson point process(PPP) for one-tier network, or several indepen... Stochastic geometry is widely employed to model cellular network. But in most existing works, base stations(BSs) are modelled following a homogeneous Poisson point process(PPP) for one-tier network, or several independent homogeneous PPP for multi-tier network, which ignore the dependence among BSs. In this paper, a three-tier UDN(Ultra dense network) with Macrocell BSs(MBS) for basic coverage, Picocell BSs(PBSs) deployed outside the coverage area of MBSs for compensating coverage holes, and Femtocell BSs(FBSs) surrounding MBSs for capacity improvement modelled by point process with inter-tier dependence is proposed. The tier association probability, the coverage probability and area spectrum efficiency(ASE) are derived. Simulation results validate our derivation, and results show that the proposed network model has 25%-45% performance gain in ASE. 展开更多
关键词 stochastic geometry tier association PROBABILITY POISSON HOLE process area spectrum EFFICIENCY COVERAGE PROBABILITY
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Process and mechanism of arable land change in Hebei Province during the past 50 years 被引量:3
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作者 XU Yue-qing (Institute of Geographical Sciences and Natural Resources Research, CAS, Beijing 100101, China College of Resource and Environment Science, Hebei Normal University, Shijiazhuang 050016, China ) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第4期47-52,共6页
Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in China. The contradiction of land shortage sharpened by high-speed economic development with pop... Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in China. The contradiction of land shortage sharpened by high-speed economic development with population growth has become a serious problem, which has restricted regional sustainable development.This paper revealed the basic process, regional differences of change and the gravity center of arable land area according to the long-series statistical data of arable land during the past 50 years. On the basis of the above mentioned, the major driving forces that influence the changes of the arable land are discussed. The research results indicate that there is a trend of obvious fluctuating decrease in arable land area during the last 50 years. The changes of arable land area undergo the process from increase to sharp decrease to gently decrease. The regional disparity of change in arable land area is very notable and the gravity center of arable land area moves to the northeast 49.22 km. Regarding the decrease in arable land, the direct driving forces include adjustments of agricultural structure and reclamation, and indirect driving forces include advance in technology, economic interest and population growth etc. 展开更多
关键词 decrease in arable land area changing process mechanism Hebei Province
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A review of stand basal area growth models 被引量:5
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作者 Sun Hong-gang Zhang Jian-guo Duan Ai-guo He Cai-yun 《Forestry Studies in China》 CAS 2007年第1期85-94,共10页
Growth and yield modeling has a long history in forestry. The methods of measuring the growth of stand basal area have evolved from those developed in the U.S.A. and Germany during the last century. Stand basal area m... Growth and yield modeling has a long history in forestry. The methods of measuring the growth of stand basal area have evolved from those developed in the U.S.A. and Germany during the last century. Stand basal area modeling has progressed rapidly since the first widely used model was published by the U.S. Forest Service. Over the years, a variety of models have been developed for predicting the growth and yield of uneven/even-aged stands using stand-level approaches. The modeling methodology has not only moved from an empirical approach to a more ecological process-based approach but also accommodated a variety of techniques such as: 1) simultaneous equation methods, 2) difference models, 3) artificial neural network techniques, 4) linear/nonlinear regression models, and 5) matrix models. Empirical models using statistical methods were developed to reproduce accurately and precisely field observations. In contrast, process models have a shorter history, developed originally as research and education tools with the aim of increasing the understanding of cause and effect relationships. Empirical and process models can be married into hybrid models in which the shortcomings of both component approaches can, to some extent, be overcome. Algebraic difference forms of stand basal area models which consist of stand age, stand density and site quality can fully describe stand growth dynamics. This paper reviews the current literature regarding stand basal area models, discusses the basic types of models and their merits and outlines recent progress in modeling growth and dynamics of stand basal area. Future trends involving algebraic difference forms, good fitting variables and model types into stand basal area modeling strategies are discussed. 展开更多
关键词 stand basal area empirical models process-based models algebraic difference hybrid models
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Study on Cultivated Land Resource Situation and Its Macro-Driving Forces in Yantai Area
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作者 Liu Xianzhao 《Ecological Economy》 2005年第4期30-37,共8页
According to the statistics of cultivated land in Yantai area during the Reform and Opening-up over the past 20 years and with the detailed survey and changing data of land use during the recent live years, this paper... According to the statistics of cultivated land in Yantai area during the Reform and Opening-up over the past 20 years and with the detailed survey and changing data of land use during the recent live years, this paper reveals the basic characteristics of the resource utilization, the basic process of the changes, regional differences, and current direction of cultivated land In addition, this paper makes a preliminary research on the major driving factors and the influence mechanism for the changes in the cultivated land area. and reaches the following conclasions: (1) There was a trend of obvious fluctuant decrease in cultivated laud area during the past 20 years. The changes of cultivated land have undergone the process - slow decrease,steep decrease, slow decrease. And there were three peak periods of cultivated land loss around 1985. 1987-1996 and 1991-1993 respectively (2) The decreased cultivated land was mainly converted into land for industry and mining, residential area. and all kinds of traffic and orchards. The increase of cultivated land mainly came from exploitation and land and arrangement and reclamation of industry and mining land (3) The economic development. population growth and policy are the dominant macro-driving factors for the decrease of cultivated land area in Yantai. The obvious sudden changes during the change process of cultivated land acreage are relevant to the national macro.policies background The rapid decrease of cnltivated land area is synchronous with the overheated economic growth resulting from the direct investment in fixed assets. Spatial distribution of the decrease in cultivated land is congruous with the differences in speed and the scale of economic growth between the different regions of Yantai area. Furthermore. the decrease in cultivated land caused by population increase cannot be ignored. 展开更多
关键词 cultivated land loss. driving mechanism change process. Yantai area
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Study of One Rainstorm Being Affected by Two Weather Systems in Jinzhou Area
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作者 YAN Zhi-yu, YANG Gui-juan Jinzhou Meteorological Bureau of Liaoning Province, Jinzhou 121001, China 《Meteorological and Environmental Research》 CAS 2011年第4期30-32,38,共4页
[Objective] The aim was to study one rainstorm process being affected by two weather system. [Method] Influenced by high trough and Mongolia cold front, high latitude trough and subtropical high shear, rainstorm occur... [Objective] The aim was to study one rainstorm process being affected by two weather system. [Method] Influenced by high trough and Mongolia cold front, high latitude trough and subtropical high shear, rainstorm occurred in Jinzhou from October 19 to 22 in 2010. In order to make the analysis clear, there were two precipitation stages. Considering precipitation, weather situation, satellite image and numerical forecast, the rainstorm process was discussed. [Result] There were two raining stages during this precipitation. The first stage was affected by high altitude trough and ground Mongolia cold front, and the last stage was influenced by high altitude trough and subtropical high shear;the high latitude air, low latitude shear,low air torrent,subtropical high and their mutual coupling effect were the main influencing system and cause for this rainstorm. Satellite image suggested that there was convective cloud developing,weakening, disappearing and regenerating around the convective cloud of water vapor passage, showing distinct train operation state. The strengthening and weakening cloud image fitted the real precipitation. Numerical forecast precisely predicted the upper air and ground situation of the generation of rainstorm, especially the report of the east-retreating and south-falling trend of subtropical high;European center forecast fitted reality. There was certain error in predicting T639. Precipitation forecast was fine. [Conclusion] The study provided basis for the meteorological service work in future. 展开更多
关键词 Influencing system RAINSTORM process analysis Jinzhou area China
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基于Process Simulate的机器人运动程序开发及应用 被引量:1
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作者 沈阳 栾会玲 《机械工程师》 2021年第6期119-121,共3页
针对目前汽车行业车身车间越来越高的自动化程度和日益复杂的车型更新,使用Tecnomatix软件进行虚拟调试,把前期设计数模导入Process Simulate模块,进行运动仿真和碰撞模拟测试,提前发现设计缺陷,并与机器人厂家联合开发运动和工艺模块,... 针对目前汽车行业车身车间越来越高的自动化程度和日益复杂的车型更新,使用Tecnomatix软件进行虚拟调试,把前期设计数模导入Process Simulate模块,进行运动仿真和碰撞模拟测试,提前发现设计缺陷,并与机器人厂家联合开发运动和工艺模块,与上位PLC进行逻辑处理,与下位应用设备进行标准化模块处理及数据通信,提前在虚拟化环境中进行验证,最终输出机器人运动和安全程序,提高了机器人程序的质量并且能够大大减少现场调试时间。 展开更多
关键词 process Simulate 机器人 运动仿真 安全区
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Evaluation of suitability area by ground source heat pump system in Baotou plain
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作者 WANG Chunpeng WANG Qinghua +2 位作者 FENG Lei FENG Ye CHENG Sanhuan 《Global Geology》 2014年第3期176-181,共6页
According to the elements of hydrogeological conditions,lithology,stratigraphic thermal physical parameters,construction technology and economic rational elements,the evaluation system of ground source heat pump( GSHP... According to the elements of hydrogeological conditions,lithology,stratigraphic thermal physical parameters,construction technology and economic rational elements,the evaluation system of ground source heat pump( GSHP) were established in Baotou plain. The factor weights were determined by using analytic hierarchy process,and the comprehensive element method was selected to evaluate the region suitability of GSHP system. The results show that the suitable area is 559. 63 km2 for utilizing GSHP in the studied area,accounting for 62. 58% of the total area; while the unsuitable area is 334. 60 km2,accounting for37.42%. The evaluating results can provide not only a scientific basis for development and utilization rationally of shallow geothermal heat in Baotou,but also offer an important reference to the other areas. 展开更多
关键词 Baotou plain ground source heat pump suitability area evaluation: analytic hierarchy process comprehensive element method
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喀什地区复播小米的品质评价
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作者 高强 杨艳 +6 位作者 路子峰 严青青 张龑 徐麟 陈润峰 郑立鹏 周伟 《山西农业科学》 2024年第3期9-14,共6页
为探究喀什地区复播的不同品种谷子小米营养品质的差异,试验以不同来源的4个谷子品种作为分析对象,对小米中的9种矿质元素Na、Mg、K、Ca、Mn、Fe、Cu、Zn、Se含量进行检测,并对其4种营养指标脂肪酸、粗蛋白、粗脂肪、淀粉含量进行检测分... 为探究喀什地区复播的不同品种谷子小米营养品质的差异,试验以不同来源的4个谷子品种作为分析对象,对小米中的9种矿质元素Na、Mg、K、Ca、Mn、Fe、Cu、Zn、Se含量进行检测,并对其4种营养指标脂肪酸、粗蛋白、粗脂肪、淀粉含量进行检测分析,最后对其生产加工方向进行综合预测。结果表明,各元素含量在不同品种谷子间差异显著,其中Na含量为8.24~31.18μg/g,Mg含量为869.42~1 580.23μg/g,K含量为2 326.80~5 033.01μg/g,Ca含量为110.64~395.88μg/g,Mn含量为11.39~21.11μg/g,Fe含量为15.94~57.46μg/g,Cu含量为0~7.51μg/g,Zn含量为15.10~35.94μg/g,Se含量为0.070 7~0.176 8μg/g。小米矿质元素总量范围为3 365.10~6 874.92μg/g,变异系数为25.95%;不饱和脂肪酸含量丰富而且在不同品种间差异显著;粗蛋白、粗脂肪、淀粉的含量范围分别是12.9%~13.69%、4.54%~6.02%、68.8%~76.76%,变异系数分别为5.00%,11.42%和4.91%。不同品种谷子小米直链淀粉含量差异不大,对其糊化温度与胶稠度分析后发现,陇谷29易蒸煮、适口性更好。不同品种谷子小米的营养品质存在差异性,陇谷29总体表现优异,晋谷21次之,二者均可作为企业生产的储备品种。 展开更多
关键词 复播 小米 营养指标 生产加工 喀什地区
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Mechanical model of precursory source proces for strong earthquakes in western Yun-nanarea——conceptandnumericalsimula┐tion
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作者 苏有锦 晏风桐 《Acta Seismologica Sinica(English Edition)》 CSCD 1996年第3期40-51,共12页
The strong earthquakes in western Yunnan area, mainly occur along great interplate strike slip faults and have a dominant depth layer about 10~20 km; the seismic rupture is characterized by strike slip rupture. Co... The strong earthquakes in western Yunnan area, mainly occur along great interplate strike slip faults and have a dominant depth layer about 10~20 km; the seismic rupture is characterized by strike slip rupture. Considering the Yunnan lithospheric structure and dynamic background, we think that earthquakes occurring at this area might have such a kind of nucleation process: because of the multi layers and heterogeneities of lithospheric structure, a zone of concentrated shear strain or of slip might be formed at the moderate or deep portions of lithosphere, and spread upward along faulting boundary, toward the earths surface under the background field of tectonic movement of lithospheric plates. The slip front will encounter the maximum shear resistance zone on the fault surface in this process, be barried and blocked, and form a seismic gap. With the increase of tectonic load, this slip zone will continuously spread forward, traverse and lead to instable crack of the whole blocked zone, and cause a great earthquake. We have derived an approximate integral equation describing this seismic process; the numerical results show that the model has an instable nonlinear accelerating evolution period which might have important significance for the generation of earthquake precursors. 展开更多
关键词 western Yunnan area seismic nucleation process mechanical model numerical simulation.
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Suitability Evaluation of Garden Landscape in Chizhou Residential Area
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作者 Zhenlong MIAO 《Asian Agricultural Research》 2016年第12期69-73,共5页
Through the field survey of construction of garden landscape in residential areas,combined with the analytic hierarchy process( AHP),this paper established a reasonable and feasible suitability evaluation system for g... Through the field survey of construction of garden landscape in residential areas,combined with the analytic hierarchy process( AHP),this paper established a reasonable and feasible suitability evaluation system for garden landscape in residential areas. Researches indicated that the environment of garden landscape in residential areas of Chizhou City in Anhui province remains at the level of intermediate and lower level,and there are great differences between different areas. In the later period of the construction,it is recommended to strengthen the construction of soft physical environment for new residential areas,and speed up the improvement of the physical environment of the residential areas already built and under construction,so as to create a livable space with beautiful environment,excellent ecology,deep community culture,and outstanding regional characteristics. 展开更多
关键词 Residential areas Analytic hierarchy process(AHP) Garden landscape Evaluation system Chizhou City
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卷烟滤棒成型加工区域集控系统实现
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作者 段青娜 沙利波 +3 位作者 罗运河 邱潇 高阔 杨四林 《机械工程与自动化》 2024年第3期147-149,共3页
针对滤棒成型作业区分散、设备种类多、制造厂家和数量多、接口协议复杂且不统一以及海量数据变量难识别等问题,设计并开发了基于OPC UA架构和实时内存数据库的就地滤棒加工区数采和监控系统。自主开发OPC服务器,实现了滤棒成型主、辅... 针对滤棒成型作业区分散、设备种类多、制造厂家和数量多、接口协议复杂且不统一以及海量数据变量难识别等问题,设计并开发了基于OPC UA架构和实时内存数据库的就地滤棒加工区数采和监控系统。自主开发OPC服务器,实现了滤棒成型主、辅设备的实时数据采集,并通过高效内存数据库服务器对生产及设备信息进行海量存储,进而实现了对滤棒成型车间生产过程信息的全面、准确迁移集成,以及对滤棒生产、产量、质量、机台效率、设备状态等信息的可视化区域集控。 展开更多
关键词 滤棒成型加工 区域集控 OPC UA 实时内存数据库
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黔西南雄武地区铀矿化与有机流体的成因联系
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作者 邱林飞 吴玉 +8 位作者 李子颖 蒋宏 徐伟 韩文文 解波 郭建 孙祥 黎丕林 邱锦鸿 《大地构造与成矿学》 EI CAS CSCD 北大核心 2024年第2期352-367,共16页
在黔西南地区,前人针对构造演化、油气流体、金矿床成矿流体和成矿模式等方面开展了大量的研究,但铀矿床研究方面还十分薄弱,尤其针对有机流体与铀成矿的关系还未开展研究。本次研究在野外地质调查基础上,对黔西南雄武地区大际山铀矿床... 在黔西南地区,前人针对构造演化、油气流体、金矿床成矿流体和成矿模式等方面开展了大量的研究,但铀矿床研究方面还十分薄弱,尤其针对有机流体与铀成矿的关系还未开展研究。本次研究在野外地质调查基础上,对黔西南雄武地区大际山铀矿床及大梨树铀矿床中典型的矿石与蚀变围岩样品开展了显微岩相学、扫描电镜‒能谱分析、电子探针、流体包裹体、激光拉曼、稳定同位素等方面研究。宏观上,铀矿体的中心部位往往呈黑色,矿体两侧呈灰色、灰褐色,矿体中心向两侧颜色逐渐变浅。镜下研究发现,铀矿物、黄铁矿等金属矿物与黑色的有机质紧密共生。激光拉曼分析指示,这些有机质经历的最高温度为185~237℃,等效镜质体反射率指示有机质处于高成熟‒过成熟阶段,具有焦沥青的特征。铀矿体外围蚀变带中饱含显示强浅蓝色荧光的轻质油,指示富烃类有机流体与成矿物质可能为同一来源,均为含铀有机流体演化而成。铀矿石中黑色有机质的^(13)C值与其赋矿碳酸盐岩表现出明显的异源特征,且与当地古油藏的C同位素具有相似性,指示焦沥青可能来源于深部侵位的古油藏。铀矿物微区年代学与有机质Re-Os年代学的研究结果在误差范围内基本一致,均为喜山期,进一步指示铀矿物和有机质是同时代地质作用的产物。黔西南雄武地区铀的沉淀应该与油气裂解‒分异作用相关,其铀矿成矿作用既不是以往认为的沉积成岩型,也不是沉积成岩叠加淋积‒热液改造型,而应该是构造作用下、深部渗出含铀富有机质成矿流体形成的渗出碳酸盐岩型铀矿床。成矿过程中,铀钼等多金属可能以微纳米超显微结构的形式随有机流体共同迁移,在温压条件变化的情况下,含矿的富烃类有机流体发生裂解‒分异作用,致使铀、黄铁矿等金属物质与重质组分(沥青)残留于破碎带或构造裂隙中而发生铀矿化,而轻质组分(轻质油)发生逃逸,部分以包裹体或孔隙流体的形式捕获于构造带或上覆地层中。 展开更多
关键词 烃类流体 裂解‒分异作用 大际山铀矿床 雄武地区 黔西南
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前胡药材产地干燥加工方法研究
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作者 谭鹏昊 程育希 +1 位作者 郭冬琴 周浓 《中国药房》 CAS 北大核心 2024年第15期1844-1848,共5页
目的比较产地不同干燥加工方法对前胡药材质量的影响,筛选其最佳产地干燥加工方法。方法分别采用传统晒干、自然阴干和电热恒温鼓风干燥、真空干燥、红外干燥和真空冷冻干燥等干燥加工方法对前胡药材进行处理,以折干率、含水量、浸出物... 目的比较产地不同干燥加工方法对前胡药材质量的影响,筛选其最佳产地干燥加工方法。方法分别采用传统晒干、自然阴干和电热恒温鼓风干燥、真空干燥、红外干燥和真空冷冻干燥等干燥加工方法对前胡药材进行处理,以折干率、含水量、浸出物含量、颜色色度值以及4种香豆素类成分含量为指标,采用逼近理想解排序法进行综合质量评价。结果不同干燥加工方法下,12份前胡药材样品的折干率为31.56%~40.10%,含水量为6.96%~8.58%,浸出物含量为27.56%~43.10%,红绿度值为1.80~7.50,黄蓝度值为19.90~30.20,明度值为46.90~59.90;伞形花内酯、白花前胡甲素、白花前胡乙素、白花前胡E素的含量分别为≤0.05、3.70~14.05、0.72~2.37、0.81~3.90 mg/g,总含量为5.47~19.65 mg/g;40℃电热恒温鼓风干燥下的前胡药材综合得分最高。结论40℃电热恒温鼓风干燥是前胡药材最佳的产地干燥加工方法。 展开更多
关键词 前胡 产地干燥加工 颜色色度值 浸出物 香豆素类成分 折干率 含水量
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