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1.
本科院校办高职学院是我国 2 0世纪末出现的一个新生事物 ,如何设置专业课程 ,提高教学质量 ,使学生一出校门就能容纳到直接为经济服务当中去 ,结合商务日语专业的具体情况对这个问题进行了思考。  相似文献   
2.
1 IntroductionAccordingtogeologicalstructure ,theGansu Ningxia Qinghaiareabelongstothenortheastmar ginofQinghai Tibetblock .Thisareahasbeenpaidmuchattentionby geo specialistsinChinaandabroadbecauseofitssignificanttectonicmovement,itsintensiveseismicity ,anditsimportanceinearth quakehazardmitigation .IntheDevelopmentPro gramonNationalKeyBasicResearchesundertheProject“MechanismandPredictionofContinentalStrongEarthquakes”,themechanismsofcontinen talstrongearthquakesarestudied ,usinghypo…  相似文献   
3.
In model inter-comparisons one major obstacle is the format of the reported data. To facilitate the analysis of the results from the different models they should all be reported in the same format. This requires that the format is flexible enough to be easily implemented into the different land surface schemes. It should also be fault tolerant and allow a few consistence checks to avoid erroneous data to be submitted. The present note describes such a format developed for the PILPS project. After discussing the aim of this new format we present the routines which are used to write and read data. Finally two applications are described which allow the user to perform a number of consistency checks on the data.  相似文献   
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5.
A constitutive relation is derived for describing the mechanical response of chalk. The approach is based on a phenomenological framework which employs chemo‐plasticity. The properties of the material are assumed to be affected by the physico‐chemical processes that occur through the interaction between the skeleton and the pore fluid. The underlying mechanism is discussed by invoking a micromechanical analysis. The performance of the framework is illustrated by examining the evolution of mechanical characteristics in the presence of different pore fluids. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
6.
邵正义  赵君亮 《天文学报》1996,37(4):377-386
本文提出了一个普适的衡量成团天体系统成员概率计算结果的有效性指数:E=1-NΣ{P(i)[1-P(i)]}/ΣP(i)Σ[1-P(i)]},并以此对以Sanders方法为基础的各种成员确定模型的有效性进行了分析.从总体上说,运动学资料(自行、视向速度等)是一类有效的观测判据.  相似文献   
7.
Volcanism throughout the Luzon arc is associated with eastwardsubduction of the South China Sea floor along the Manila Trench.The southern section of the arc, the focus of this study, extendsfrom the Lingayen-Dingalan fault to the small islands just southof Luzon. Two segments appear to exist along this section ofthe arc the northern Bataan and southern Mindoro segments whichare separated by the Macolod Corridor. The volcanic rocks have typical arc phenocryst mineralogies:olivine, clinopyroxene, plagioclase, and titanomagnetite inthe most mafic rocks and clinopyroxene, plagioclase, orthopyroxene,titanomagnetite, ? amphibole in the more felsic samples. Complexzoning, sieve textures, and decoupling of incompatible traceelements suggest that processes such as assimilation have takenplace. The rocks from the study area range from basalts to rhyolitesand show typical calc-alkaline features. The rocks of the MacolodCorridor and Mindoro segment are particularly enriched in largeion lithophile elements (LILE), light rare earth elements (LREE),and radiogenic Sr compared with the Bataan segment. The datafall within the mantle array on Sr-Nd isotopic diagrams andgrade toward higher Sr and lower Nd isotopic values from northto south. A likely source for the volcanics of this study is either amid-ocean ridge basalt (MORB)-type mantle that undergoes higherdegrees of partial melting than regions involved in MORB generationor a previously depleted source. We suggest that the high fieldstrength element (HFSE) anomalies have been derived throughdifferential element partitioning during fluid transport fromthe subducted lithosphere to the mantle wedge. Continental crustal material seems to play a significant roleparticularly in the Macolod Corridor and the Mindoro segment,based on the high LILE, La/Sm ratios, radiogenic Sr isotopes,and 18O values. The Macolod Corridor and the Mindoro segmenthave undergone source contamination by crustal material fromthe North Palawan-Mindoro crustal block either during the collisionof this block with the Manila Trench or by subduction of sedimentsrich in this crustal material. A similar component has alsobeen detected in the Bataan segment but in minor amounts. Thetrace element and isotopic differences between the northernand southern sections of the arc are interpreted in terms ofvariable composition (i. e., variable amounts of a crustal componentintroduced from the Palawan-Mindoro crustal terrain) of themetasomatic fluids released into the source.  相似文献   
8.
实验条件对X射线衍射物相定量分析结果的影响   总被引:8,自引:6,他引:2  
通过实验验证了多物相试样X射线衍射定量分析的基体效应,着重研究了参比强度K值、衍射强度、混合物各物相粒度、X射线管功率等实验条件对物相定量分析结果的影响。结果表明,物相定性分析是定量分析的前提,采用积分强度、使各物相颗粒尽可能细而且均匀、采用较高的X射线管功率以及适合的扫描速率均有利于提高物相X射线衍射定量分析的准确度。  相似文献   
9.
MODFLOW is a groundwater modeling program. It can be compiled and remedied according to the practical applications. Because of its structure and fixed data format, MODFLOW can be integrated with Geographic Information Systems (GIS) technology for water resource management. The North China Plain (NCP), which is the politic, economic and cultural center of China, is facing with water resources shortage and water pollution. Groundwater is the main water resource for industrial, agricultural and domestic usage. It is necessary to evaluate the groundwater resources of the NCP as an entire aquifer system. With the development of computer and internet information technology it is also necessary to integrate the groundwater model with the GIS technology. Because the geological and hydrogeological data in the NCP was mainly in MAPGIS format, the powerful function of GIS of disposing of and analyzing spatial data and computer languages such as Visual C and Visual Basic were used to define the relationship between the original data and model data. After analyzing the geological and hydrogeological conditions of the NCP, the groundwater flow numerical simulation modeling was constructed with MODFLOW. On the basis of GIS, a dynamic evaluation system for groundwater resources under the internet circumstance was completed. During the process of constructing the groundwater model, a water budget was analyzed, which showed a negative budget in the NCP. The simulation period was from 1 January 2002 to 31 December 2003. During this period, the total recharge of the groundwater system was 49,374 × 10m3 and the total discharge was 56,530 × 10m3 the budget deficit was −7,156 × 10m3. In this integrated system, the original data including graphs and attribution data could be stored in the database. When the process of evaluating and predicting groundwater flow was started, these data were transformed into files that the core program of MODFLOW could read. The calculated water level and drawdown could be displayed and reviewed online.  相似文献   
10.
Unconsolidated sand, gravel and clay deposits near Beihai and in the Leizhou Peninsula in southern China form an unconfined aquifer, aquitard and a confined aquifer. Water and soil samples were collected from the two aquifers in the coastal Beihai area for the determination of chemical compositions, minerals and soluble ions. Hydrogeochemical modeling of three flow paths through the aquitard are carried out using PHREEQC to determine water–rock interactions along the flow paths. The results indicate that the dissolution of anorthite, fluorite, halite, rhodochrosite and CO2, and precipitation of potash feldspar and kaolinite may be occurring when groundwater leaks through the aquitard from the unconfined aquifer to the confined aquifer. Cation exchanges between Na and Ca can also happen along the flow paths.  相似文献   
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