Physical geographical background of the culture of traditional Chinese residential architecture

ThetheSisistoexplainthebasicfactorsreferringtothetraditionalChineseresidentialarchitecturebasicallyfinalizedintheMingandQingdynastiesinthecountry'sspecificphysicalenvironment.Restrainedbyaxialfactors,itadaptsitselftotheself-sufficientnatural~nomy.Itisfiexiblydesigned,rsoablyfunctioned,economicallyconstructedandfeaturedbyremarkablelocalcharacteristics.IINFLUENCEOFCLIMATEONTRADITIONalarSIOCNTIAnANCnITh~arNinetyPercentofChina'spopulationinhabitstheeasternareawithinthedemarcati…     

Impact of 4DVAR assimilation of rainfall data on the simulation of mesoscale precipitation systems in a mei-yu heavy rainfall event

The multi-scale weather systems associated with a mei-yu front and the corresponding heavy precipitation during a particular heavy rainfall event that occurred on 4 5 July 2003 in east China were successfully simulated through rainfall assimilation using the PSU/NCAR non-hydrostatic, mesoscale, numerical model （MM5） and its four-dimensional, variational, data assimilation （4DVAR） system. For this case, the improvement of the process via the 4DVAR rainfall assimilation into the simulation of mesoscale precipitation systems is investigated. With the rainfall assimilation, the convection is triggered at the right location and time, and the evolution and spatial distribution of the mesoscale convective systems （MCSs） are also more correctly simulated. Through the interactions between MCSs and the weather systems at different scales, including the low-level jet and mei-yu front, the simulation of the entire mei-yu weather system is significantly improved, both during the data assimilation window and the subsequent 12-h period. The results suggest that the rainfall assimilation first provides positive impact at the convective scale and the influences are then propagated upscale to the meso- and sub-synoptic scales.
Through a set of sensitive experiments designed to evaluate the impact of different initial variables on the simulation of mei-yu heavy rainfall, it was found that the moisture field and meridional wind had the strongest effect during the convection initialization stage, however, after the convection was fully triggered, all of the variables at the initial condition seemed to have comparable importance.     

一次新型液态CO2播撒效果的数值模拟

利用三维积层混合云人工增雨数值模式对2002年7月11日的一次天气过程进行了由播撒液态CO2引起的微物理量变化及云动力影响的数值模拟。结果表明:播撒后,云中最大上升气流速度增大,由未播撒时的0.37 m/s增大到播撒后的0.54 m/s,播撒使云中出现最大上升速度W的时间比未播撒提前了4 min,表明播撒液态CO2影响了云的动力过程。同时与未播撒相比:云中雨水含量最大值由1.04 g/kg增加到1.40 g/kg;冰粒子含水量的出现提前了88 min,最大值的出现提前了76min;冰粒子浓度的出现提前了72 min,最大值的出现提前了72 min;雪粒子含水量的出现提前了72 min,最大值的出现提前了128 min;云水含量最大值由1.21 g/kg减小到0.87 g/kg。证明了播撒液态CO2后可影响云的微物理过程,从而导致地面降水的增加。     

Quasi-waveform seismic tomography of crustal structures in the capital circle region of China

Seismic tomography is one of the main tools to explore the interior of the earth.In this study,the quasi-waveform seismic tomographic method is used for the first time to reveal the crustal structures in the capital region of China.3-D highresolution V_P,V_S and the Poisson’s ratio models are generated by inverting 29839 direct P-and 29972 direct S-wave traveltimes selected from 3231 local earthquakes.The results reveal strong crustal heterogeneities.The velocity anomalies at shallow depths are well consistent with surface geologic structures.The relatively low-velocity anomaly layer in the middle crust may be the result of multiple phases of tectonic activity.Earthquakes generally occurred on the boundaries of high-and low-velocity and Poisson’s ratio anomalies.There are obvious low-velocity anomalies below the hypocenters of the Tangshan earthquake and the historical Sanhe-Pinggu earthquake,implying the existence of fluids.The similar velocity structures around the hypocenters of the two earthquakes indicate that the occurrences of the two earthquakes may be related to the same mechanism.The highresolution velocity models provide important observational constraints on the small-scale heterogeneities and dynamic mechanism of the crust in the capital region of China.     

Precipitation‐runoff processes in Shimen hillslope micro‐catchment of Taihang Mountain,north China

Precipitation runoff is a critical hillslope hydrological process for downslope streamflow and piedmont/floodplain recharge. Shimen hillslope micro‐catchment is strategically located in the central foothill region of Taihang Mountains, where runoff is crucial for water availability in the piedmont corridors and floodplains of north China. This study analyzes precipitation‐runoff processes in the Shimen hillslope micro‐catchment for 2006–2008 using locally designed runoff collection systems. The study shows that slope length is a critical factor, next only to precipitation, in terms of runoff yield. Regression analysis also shows that runoff is related positively to precipitation, and negatively to slope length. Soil mantle in the study area is generally thin and is therefore not as critical a runoff factor as slope length. The study shows a significant difference between overland and subsurface runoff. However, that between the 0–10 and 10–20 cm subsurfaces is insignificant. Runoff hardly occurs under light rains (<10 mm), but is clearly noticeable under moderate‐to‐rainstorm events. In the hillslope catchment, vertical infiltration (accounting for 42–84% of the precipitation) dominates runoff processes in subsurface soils and weathered granite gneiss bedrock. A weak lateral flow (at even the soil/bedrock interface) and the generally small runoff suggest strong infiltration loss via deep percolation. This is critical for groundwater recharge in the downslope piedmont corridors and floodplains. This may enhance water availability, ease water shortage, avert further environmental degradation, and reduce the risk of drought/flood in the event of extreme weather conditions in the catchment and the wider north China Plain. Copyright © 2011 John Wiley & Sons, Ltd.     

Characterizing the hydraulic properties of unsaturated sand considering various porosities and drying‐wetting paths of the retention curve

Previous studies have shown that water retention curve (WRC) and the hydraulic conductivity vary because of changes of the void ratio or porosity of soil. However, limited documents pointed out the change of hydraulic properties of soil when compacted to different porosities while considering both of the drying and wetting processes of the WRC. This information is sometimes necessary for research like finger flow analysis or the occurrence of wetting and drying cycles as what would be seen in the field. Therefore, this study aims to examine the change of WRC characteristics with varied porosity considering both of the drying and wetting path in WRC by conducting a sand box experiment. Results show that the same type of sand compacted to various porosities have different hydraulic parameters. Hydraulic conductivities generally decrease with reduced porosities; shape parameter α of the van Genuchten equation (1980) linearly decreases with declining porosity and shape parameter n in a reversal manner for the sands of interest whether in the drying process or wetting process. The unsaturated properties of sand are further characterized by inspecting the variations of moisture content, matric suction and vertical displacement of soil body subject to periodic changes of the water level by another sand box experiment. The outcomes suggest that the saturated water content and residual water content are changing during the wetting–drying process, which can be an implication of the changed properties of WRC. The characteristics of volumetric deformation might be varied as well because of the observation of the dissimilar patterns of the changing vertical displacements among each wetting–drying process. Infiltration patterns of the sands also are identified through numerical modelling by introducing a constant infiltration flux from the surface followed by a no‐influx condition. Results indicate that less water accumulates in the sand near the surface for the sand compacted to higher porosity, but water can move deeper. Hydraulic conductivity is found as the prime factor dominating the evolvement of wetting fronts. However, shape parameters of water retention curves also affect the infiltration pattern to some extent. In addition, different sands with similar porosities can have quite different infiltrating characteristics. Copyright © 2012 John Wiley & Sons, Ltd.     

JCXA——733型电子探针快速半定量分析程序

在近代科学技术发展前缘之一的微束分析中,电子探针X射线显微分析仪是目前相当活跃的微区微量物质成份分析的设备.六十年代初期,电子探针开始被应用于地质领域进行矿物成份分析,至今它已成为矿物岩石学,地球化学、矿床综合评价及综合利用等众多科研课题研究的重要手段.我们使用的JCXA-733型电子探针装配的是美国DEC公司PDF-11型电子计算机,RX02双软盘驱动装置、LA-36型宽行打字机,RT-1l操作系统     

Inductive Strain Gage

The essential principle, technical feature, and application of inductive strain gage are described in this paper. This kind of strain gage is developed by our institute and has become product with invention patent.     

广西弧形构造探讨

广西构造实为一弧形构造,它由四个并排的北东—北西向的轭状弧带所组成。每个弧带的前部,为坚硬的岩块所组成,所产生的断裂及岩浆活动对寻找与火成岩有关的矿产有一定意义。每个弧带的后部,产生盆地型沉积,有利于沉积矿产的形成。