与铜、金矿化有关的富碱侵入岩矿物化学研究

以哀牢山—金沙江富碱侵入岩带内与金矿化有关的姚安正长斑岩和与铜矿化有关的马厂箐花岗斑岩为研究对象,开展了系统的矿物化学研究。结果表明,姚安岩体形成的温压条件为(818±50)℃和0.9×108~1.3×108Pa,马厂箐岩体形成的温压条件为(729±50)℃和2.2×108~2.8×108Pa,两岩体的氧逸度均高于地幔石英-橄榄岩-磁铁矿出溶线,相对于马厂箐岩体而言,姚安岩体结晶时的氧逸度更高。两岩体矿化作用的差异与岩浆的分异程度有密切的关系。相对于铜矿化而言,氧逸度较高的岩浆有利于金矿化。     

安徽宁国胡乐奥陶系再研究

宁国胡乐地层区划属扬子地层区江南地层分区。区内奥陶系分布广,出露全,剖面完整且层序清楚,化石丰富,在国内及大区域内均具典型性和代表性。本区奥陶系自下而上为谭家桥组、宁国组、胡乐组、砚瓦山组、黄泥岗组、新岭组,与下伏晚寒武世至早奥陶世西阳山组、上覆晚奥陶世至早志留世霞乡组及系内各组间均为连续沉积整合接触。在胡乐梅树下发现原砚瓦山组下部地层,在胡乐将军岭首次发现宁国组浊流沉积及其鲍玛序列。     

Simulation of the Effect of Water-vapor Increase on Temperature in the Stratosphere

To analyze the mechanism by which water vapor increase leads to cooling in the stratosphere, the effects of water-vapor increases on temperature in the stratosphere were simulated using the two-dimensional, interactive chemical dynamical radiative model (SOCRATES) of NCAR. The results indicate that increases in stratospheric water vapor lead to stratospheric cooling, with the extent of cooling increasing with height, and that cooling in the middle stratosphere is stronger in Arctic regions. Analysis of the radiation process showed that infrared radiative cooling by water vapor is a pivotal factor in middle-lower stratospheric cooling. However, in the upper stratosphere (above 45 km), infrared radiation is not a factor in cooling; there, cooling is caused by the decreased solar radiative heating rate resulting from ozone decrease due to increased stratospheric water vapor. Dynamical cooling is important in the middle-upper stratosphere, and dynamical feedback to temperature change is more distinct in the Northern Hemisphere middle-high latitudes than in other regions and signiffcantly affects temperature and ozone in winter over Arctic regions. Increasing stratospheric water vapor will strengthen ozone depletion through the chemical process. However, ozone will increase in the middle stratosphere. The change in ozone due to increasing water vapor has an important effect on the stratospheric temperature change.     

当前国内酸雨研究进展

回顾了我国在酸雨研究方面所获得的成果,包括酸雨的时空分布特征、影响因素、生态影响模拟以及控制对策等4个方面的内容.大量的研究表明,近些年来酸雨污染的范围有所增加、程度有所加重.酸雨的形成是多种自然和人为因素共同作用的结果,与特定的气象条件、天气类型和大气环流等有密切的关系.针对酸雨污染有所加重的趋势,必须采取有效的控制对策.     

珠江三角洲城市地区MODIS气溶胶光学厚度产品的检验分析

根据2004年1—11月地面太阳光度计的气溶胶光学厚度的观测数据,对美国航空航天局(NASA)发布的中分辨率成像光谱仪气溶胶光学厚度产品(MODIS AOD C004)在珠江三角洲城市地区的准确性进行了检验,并分析了造成MODIS AOD误差的可能原因。分析结果表明:⑴MODIS AOD的误差在NASA的预期误差范围内,MODIS AOD可作为气候变化的研究和区域大气污染监测的有效手段。⑵与世界上其他地区的检验结果类似,MODIS AOD在珠江三角洲城市地区存在一定的系统性偏差:当AOD较小时,MODIS AOD值大多高估,而当AOD比较大时,MODIS AOD值偏低,这一系统性偏差大于全球平均偏差。其中广州和南海的偏差最为显著,东莞和番禺次之。⑶导致MODIS AOD在珠江三角洲城市地区出现较大系统性偏差的原因包括:珠江三角洲工业化和城市化的发展,使地表的植被覆盖率已大幅减少,MODIS AOD反演所采用的地表反照率估算值可能偏小;气溶胶模型中设定的单散射反照率值偏高,低估了珠江三角洲城市地区气溶胶的吸收性。     

地下水硝酸盐污染与治理研究进展综述

地下水的硝酸盐污染是全球所面临的一个日益严重的问题,对硝酸盐污染的地下水修复技术的研究也自然成为近年来国内外学者研究的热点。就地下水硝酸盐污染的机理和途径、对人体及其它生物的危害以及修复技术等方面作了详细介绍,另外,就地下水硝酸盐污染的治理引用了工程实际加以说明。最后指出了未来地下水硝酸盐污染治理研究的方向。     

液化场地区间隧道地震响应分析

为研究液化场地区间隧道的动力响应,利用FLAC3D软件分析一致激励、局部液化和行波激励对隧道结构动力响应的影响.计算结果表明:地基土液化改变了隧道衬砌的受力状态,衬砌的破坏位置由非液化场地的拱肩和拱脚处转成了液化场地的仰拱和拱腰位置;与液化场地相比,隧道穿越局部可液化土层时,破坏位置扩展到衬砌整个断面;与一致激励相比,...     

Synthesis, Characterization and Antibacterial Activity of New Ln( Ⅲ) Complexes with an Unsymmetrical Schiff Base Ligand

A new unsymmetrical Schiff base ligand (H2LLi) was synthesized using L-lysine, salicylaldehyde and 2-hydroxyprepared and characterized by elemental analyses, IR spectra, UV spectra, TG-DTG and molar conductance.The antibacterial activities of the ligand and its complexes are also studied.The antibacterial experiments indicate that the ligand and its complexes possess antibacterial activity against Escherichia coli, Staphylococcus aureus and Bacillus subtilis and that the complexes have higher activity than those of the ligand.     

Ecological changes and the tradeoff and synergy of ecosystem services in western China

Since the implementation of the Development of Western Regions in 2000, a series of major ecological construction projects have been implemented, leading to a series of changes in the ecological conditions and ecological services of western China. This study calculated the amount of ecosystem services in total in the western region from 2000 to 2019, and analyzed ecological changes and the characteristics of spatio-temporal variations in ecological services. A relevant analysis method was applied to explore the tradeoff and synergy of service. It was found that the area of settlements and wetland ecosystems in the western region increased significantly from 2000 to 2015, whereas grassland showed a downward trend year by year. The vegetation fraction showed a decreasing belt-like distribution from south to north. It showed a fluctuating increase during 2000 to 2019, with inter-annual and large spatial differences. The water conservation service (WCS) had a slight downward trend from 2000 to 2019, and the main decreasing areas were distributed in southeastern Tibet, the western part of the Three Rivers Source region, and the karst rocky desertification area. The soil conservation service (SCS) showed an increasing but fluctuating trend, with the greatest increases observed in the Loess Plateau region, western Sichuan and Yunnan, northwest Tibet, and southeast Tibet. The windbreak and sand fixation service (SFS) showed a downward trend, and the sharp decline was mainly in the central and western parts of Inner Mongolia, Tibet and parts of northern Xinjiang. Ecosystem supply and WCS, and SCS were mainly synergistic, which were found in areas north of the Qinling Mountains-Huaihe River (QM-HR) line, especially in Ningxia and Inner Mongolia. Ecosystem supply was mainly tradeoffs with SFS, and it was found in the agriculture-pastoral transition zone. The synergistic degree of ecosystem services in areas subjected to ecological engineering policy was greater than that in non-engineering areas. Quantitative assessment of ecosystem service changes and their tradeoffs is helpful for scientific ecological management and maximizing ecological benefits.     

基于EMD 和集合预报技术的气候预测方法

气候系统是典型的非平稳性系统,然而对于气候观测数据的处理通常是在时间序列平稳的假定下完成的,比如气温和降水的多步预报,这通常会导致预报准确度较低。为改进该缺陷,首先将非平稳数据序列分解成平稳的、多尺度特征的本征模态函数分量(IMF),再使用数值集合预报与逐步回归分析相结合的方式对每一个IMF 分量构建不同的预报模型,最后线性拟合成预报结果。通过Visual Studio 2008 开发平台使用上述方法建立了一个短期气候预报系统,采用广西区88 个气象站1957—2005 年的2 月距平气温数据进行实际验证。结果表明,相对于普通预测和单一预测方法,加入了EMD 和集合预报技术的方法在仅用历史资料进行多步预测的情况下,对于气候的变化趋势以及突发性气候具有更好的预报能力。