开封断裂第四纪活动特征

开封断裂是郑州-开封断裂带的重要组成部分,也是黄河中下游平原的一条重要控制性断裂。利用浅层地震勘探发现,开封断裂为总体走向EW,倾向N的正断层;断裂分为东、西2支,断裂活动性具有明显的分段特征,东支活动性较西支强。钻孔联合剖面揭示开封断裂东支断裂上断点埋深27～35 m,根据地层年代学结果,其最新活动时间为晚更新世。研究成果为开封市城乡规划、重大工程选址和地震区划工作提供了重要的基础数据。     

中国农业气象模式(CAMM1.0)构建与应用

为发展适宜中国区域农业种植特点的农业气象模式,基于国外作物生长模拟方法,通过模式机理过程改进或重构以及应用方式革新,建立了中国农业气象模式（Chinese AgroMeteorological Model version 1.0,CAMM1.0）。CAMM1.0利用平均温度和土壤水分改进了作物发育进程模式,利用土壤水分改进了作物叶片光合作用、干物质分配和叶面积扩展过程模式,通过蒸发比法扩展了作物蒸散过程模式;自主建立了基于发育进程的冬小麦株高、基于遥感信息的作物灌溉、遥感数据同化、作物长势与灾害评价等模式。基于互联网技术构造了实时运转平台,主要功能包括作物生长过程实时常规模拟与用户个性化定制模拟。CAMM1.0的部分子模式采用多种方法构造,便于多模式集成。CAMM1.0对作物发育进程、光合过程、株高的模拟效果较好,但对土壤水分变化过程的拟合略差,模拟产量略偏低。CAMM1.0评价淮河流域夏玉米年际干旱减弱而涝渍增加的趋势与实际基本相符。     

Research on the panel adjustment method of an active main reflector for a large radio telescope

The surface accuracy of a large parabolic antenna is an important indicator to evaluate the quality of the antenna.It not only directly affects the antenna’s aperture efficiency,thereby determining the shortest wavelength that the antenna can work,but also affects the main lobe width and side lobe structure of the antenna pattern.Microwave holography is an important method for parabolic antenna profile detection.In this article we adopt a new algorithm to adjust the panels for the large radio telescope with an active main reflector through the TM65 m antenna’s aperture phase profile.The panels of the TM65 m radio telescope is in a radial pattern with 14 rings.Each corner of the panel is fixed on the screw of the actuator to move up and down,and the adjacent corners of the four panels share an actuator.We use the method of plane fitting to calculate the adjustment value of every panel’s corner.But one actuator,which simultaneously controls the common corner of the adjacent panels,will have different adjustment values according to the different plane fitting equation based on adjacent panels.In this paper,the adjustment value of the adjacent panels’crosspoints are constrained to be equal to the constraint condition to calculate each actuator’s adjustment value of the TM65 m radio telescope.Through multiple adjustments and application of the new algorithms,the accuracy of the TM65 m antenna reflector profile has been improved from the original 0.28 mm to the current 0.19 mm.     

南极长城站至莫斯科和伊尔库茨克路径上时延的测量与传播路径研究

本文介绍了利用在南极长城站接收来自ＲＷＭ（莫斯科）和ＲＩＤ（伊尔库茨克）台的授时信号的无线电波时延的测量方法，并依据１９９１年４月至１９９１年９月所测量的传播时延数据分析了电波传播路径。说明了沿长、短大圆路径的传播时段。判定存在着非大圆路径传播并阐明了关于非大圆路径传播的一些变化规律。对非大圆路径发生的条件进行了探讨     

Transformation relationship among different magnetic minerals within loess-paleosol sediments of the Chinese Loess Plateau

The dominant magnetic minerals and carriers of magnetic signals within the Chinese Loess Plateau are magnetite, maghemite, hematite, and goethite. In this study, we investigated the provenance and evolution of magnetic minerals during loess pedogenesis, using X-ray diffraction (XRD) and optical and electron microscopy, including field emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM). Our results reveal that single- and multiphase mineral assemblages among magnetic minerals in the loess-paleosol sequence have been formed. Partial oxidation of coarse eolian magnetite has occurred in the desert source area and the oxidation degree is enhanced after deposition of the dust upon the Chinese Loess Plateau. This mode of origin resulted in a microtexture consisting of an inner magnetite core surrounded by a hematite rim, and strongly affected the magnetic characteristics of the loess. Goethite coexists with hematite in the loess and paleosol, and nanometer-scale hematite is formed upon goethite rims via dehydration. Our study provides direct mineralogical evidence of the magnetic record and paleoclimatic implications of the loess-paleosol sequence of the Chinese Loess Plateau. Supported by National Natural Science Foundation of China (Grant Nos. 40772032 and 40573054) and National Basic Research Program (Grant No. 2007CB815603)     

Porosity and wave velocity evolution of granite after high-temperature treatment: a review

The evolution of porosity and changes in wave velocity in granite after high-temperature treatment has been experimentally investigated in different studies. Statistical analysis of the test results shows that there is a temperature threshold value that leads to variations in porosity and wave velocity. At a temperature that is less than 200 °C, the porosity of granite slowly increases with increases in temperature, while the wave velocity decreases. When the temperature is greater than 200 °C (especially between 400 and 600 °C), the porosity quickly increases, while the wave velocity substantially decreases. The temperature ranges of room temperature to 200 and 200–400 °C correspond to the undamaged state and the micro-damage state, respectively. The results confirm that there is an important link between the variations of physical and mechanical properties in response to thermal treatment. By studying the relationships among rock porosity, wave velocity and temperature, this provides the basis for solving multi-variable coupling problems under high temperatures for the thermal exploitation of petroleum and safe disposal of nuclear waste.     

不同采样点数量下土壤有机质含量空间预测方法对比

运用普通克里格、泛克里格、协同克里格和回归克里格4种方法,结合由DEM获取的高程因子以及土壤全氮和阳离子交换量（CEC）,预测了黑龙江省海伦市耕地有机质含量的空间分布。不同样点数量下海伦市土壤有机质含量的空间变异结构分析表明,样点数量多并不一定能够识别土壤有机质含量的结构性连续组分,最优化的布置采样点位置可能比单纯增加...     

Geochronology and petrogenesis of the post-orogenic Cu–Ni sulfide-bearing mafic–ultramafic complexes in Jilin Province, NE China

Northeastern (NE) China is a well-documented example of a collisional zone characterized by widespread post-orogenic granites and mafic–ultramafic complexes. Based on a study of the Hongqiling and Piaohechuan Cu–Ni sulfide-bearing mafic–ultramafic complexes in central Jilin province, we present geological, petrological, geochemical and geochronological data which indicates their post-orogenic origin.The Hongqiling complex comprises pyroxenite, olivine websterite, lherzolite, gabbro and leucogabbro. Zircon U–Pb SHRIMP analyses on a leucogabbro of the Hongqiling complex yield a weighted mean ²⁰⁶Pb–²³⁸U age of 216±5 Ma. The Piaohechuan complex is composed of gabbro, pyroxenite and dolerite, exposed as dikes. A plagioclase-bearing pyroxenite has a U–Pb zircon weighted mean ²⁰⁶Pb–²³⁸U age of 217±3 Ma, identical to that of the Hongqiling complex. These ages are coeval with the emplacement of A-type granites in the area, but slightly younger than the regional metamorphism (240 Ma) and syn-orogenic granitic magmatism (246±4 Ma). This suggests that these mafic–ultramafic complexes are post-orogenic in origin. The age data also indicated a short period of lithospheric stabilization of about 30 Ma after cessation of orogenic activity.Geochemical investigation indicates that the primary mafic magma was a lithospheric mantle-derived basalt resulting from the upwelling of asthenosphere due to lithospheric delamination during post-orogenic processes. The magmatic source was contaminated by a small amount of crustal material, and subsequent crystal fractionation resulted in the Cu–Ni mineralization.The widespread occurrence of mafic–ultramafic complexes in the Xing'an–Mongolian Orogenic Belt of NE China and in the Altay–Tianshan–Junggar Orogenic Belt of Northern Xinjiang indicates that mafic intrusions are an important magmatic suite that evolved during post-orogenic processes. Portions of this mafic magma could have underplated the lower crust, and served as the heat source for associated late-stage granitic magmas.     

呼和浩特市区污染状况分析

文章利用呼和浩特市2006—2009年环境监测点监测的SO2、NO2和PM10平均浓度资料进行统计分析,得到:(1)呼和浩特市SO2日平均浓度在0.017～0.188mg·m-3之间,超标率为4.0%,NO2在0.026～0.081mg·m-3之间,未超过国家二级标准,PM10在0.036～0.332mg·m-3之间,超标率达到6.5%;(2)污染物浓度最小的月份是7月、8月,最大的月份是1月和12月;(3)近年呼和浩特污染物浓度总体呈下降趋势。     

内蒙古大克泊碱湖氮移除及其影响因素

为了研究碱湖N₂O释放速率及其对盐度与pH的响应,选取内蒙古大克泊碱湖的五个沉积物样点,采用¹⁵N同位素标记模拟实验,研究反硝化和厌氧氨氧化的速率、相对比例和气体产生情况,揭示高盐和高pH对碱湖氮移除的影响。发现大克泊湖潜在氮移除速率为0~16.06 n mol N mL-1 h-1,潜在反硝化速率为0~12.62 n mol N mL-1 h-1,潜在厌氧氨氧化速率为0~9.81 n mol N mL-1 h-1;当盐度34.00 g·L-1与pH 10.22时,厌氧氨氧化对氮移除贡献较大,达到43.18%~71.79%。反硝化过程气体产物以N₂为主,几乎无N₂O气体释出。另外,该区域潜在氮移除速率与pH呈正相关关系,与TOC、NO-₃、HCO-₃呈负相关关系;未发现氮移除速率与盐度之间的相关关系。因此,在研究的碱湖中,氮移除过程中主要为N₂排放,而N₂O低于检测水平;氮移除过程的影响因素复杂且不限于最主要的环境变量(盐度与pH)。这些结果为研究湖泊N₂O排放提供了数据基础。