铂钯多金属矿矿物化学成分矿物组成矿石结构构造及赋存状态研究

内蒙古地区西部某超基性岩带探明的铁铂钯多金属矿,铂钯品位较低,规模尚未控制。但铂钯属于稀有贵金属资源,对其化学成分、矿物组成、矿石结构构造和铂钯矿物赋存状态进行研究,为可选性试验提供必要的技术依据,十分必要。     

State of the art and practice of pavement anti-icing and de-icing techniques

Pavement snow and icing are worldwide problems, but effective countermeasures are just beginning to be developed in China. The two most common snow and ice removal methods are mechanical clearance and chemical melting, and the advantages and disadvantages of each approach are discussed here, including environmental and structural damage caused by corrosive snow melting agents. New developments in chemical melting agents and mechanical equipment are discussed, and an overview of alternative thermal melting systems is presented, including the use of geothermy and non-geothermal heating systems utilizing solar energy, electricity, conductive pavement materials, and infrared/microwave applications. Strategic recommendations are made for continued enhancement of public safety in snow and ice conditions.     

Research advances in eco-hydrological process and function

Present studies on the coupling relationship and hydrology mechanism between basin ecosystem and hydrological process has become an international research frontier in hydrology. This paper investigates this coupling relationship, and also summarizes research and presents a method of combining isotopic technology with hydro-chemical methods, for the study of eco-hydrological process and function in different landscape zones. We then examine research trends for future direction and development of this field.     

大麦屿港区规划污水排放中化学需氧量对乐清湾海域环境的影响及环境容量研究

浙江是海洋大省,沿海港口开发已成为浙江省"十二五"期间重大战略,港口开发中污水排放对海洋环境的影响亦成为社会重点关注的问题之一。文章采用MIKE21软件,在乐清湾已知测点潮流、潮位、水质化学需氧量本底浓度以及大麦屿港区规划污水排放口、化学需氧量排放源强、环境目标值等基础资料的前提下,进行潮流场模拟,采用污染物扩散水质模式预测台州港大麦屿港区规划污水排放中化学需氧量对乐清湾海域环境的影响,并计算污水排放口周边混合区范围内化学需氧量的环境容量。结果表明,大麦屿港区规划污水排放中化学需氧量对乐清湾海域影响较小,整个乐清湾内的化学需氧量浓度增量在0.001～0.005mg/L之间,增量大于0.003mg/L区域仅限于排污口附近;海水中化学需氧量环境容量较大,污水中化学需氧量排放量仅占环境容量的0.083%。     

地质样品Sr和Nd同位素的化学分离方法改进

多接收器等离子体质谱仪(MC-ICP-MS)高精度同位素组成的准确测定,依赖于对样品中待测元素的分离纯化。改进了Rb-Sr和Sm-Nd化学分离方法,检测AG50W-X12树脂及P507萃淋树脂对Rb-Sr和Sm-Nd的分离效果,并通过测定标准物质中Sr和Nd的同位素组成进行验证。结果表明,AG50W-X12树脂经2次分离能有效去除Rb,满足MC-ICP-MS高精度测定Sr同位素比值的要求;P507萃淋树脂能很好实现Sm-Nd分离,同时去除大部分Ce,满足仪器高精度测定Nd同位素比值的需要。     

地下水灌溉回水对黄河流域化学风化CO_2消耗估算的影响

本文根据2012年6月和2013年5月采集的河南、宁夏和内蒙等引黄灌区地下水实测数据,并结合文献数据,探讨了引黄灌区地下水离子组成的分布特征。结果表明:因受蒸发作用和人为因素影响较小,深层地下水矿化度和HCO-3的浓度小于浅层水,但HCO-3占阴离子比例大于浅层水。因各灌区蒸发量、降雨量以及岩性的不同,浅层地下水化学组成和风化来源阳离子浓度在各灌区表现出较大的差异。HCO-3占阴离子的比例在河南灌区最高,内蒙灌区中部和宁夏灌区次之,内蒙灌区东西部最低。河南和内蒙灌区风化来源阳离子浓度相差不多,均大于宁夏灌区。灌区浅层地下水灌溉回水高估的黄河流域化学风化消耗CO2的量为23.3×108 mol/a。     

南黄海北部B03孔沉积物的重矿物特征及物源指示意义

本文对取自南黄海北部的B03孔岩芯(330cm)沉积物进行了粒度和重矿物特征分析,并运用电子探针技术,分析了其典型层位角闪石的矿物化学特征。研究表明,B03孔柱状样为均一连续的粉砂质沉积,重矿物含量较低(平均仅0.65%),主要为云母类和闪石类矿物,岩芯以85cm处为界分为上、下2个沉积层,其重矿物组合分别为普通角闪石-云母类矿物-绿帘石和云母类矿物-普通角闪石-绿帘石。角闪石的EPMA分析显示其种属主要为镁角闪石,其次为镁钙闪石、铁镁钙闪石及阳起石,成因以中酸性侵入岩与中高级变质岩为主,上下沉积层角闪石特征元素Mg/Fe2+比值分别为2.03、1.90。综合分析认为,岩芯的主要物源为黄河源物质及山东半岛陆架基岩剥蚀产物的混源,上下沉积层的矿物特征差异暗示了沉积物源发生了变化,其分界线可能代表了黄河1855年改道事件在山东半岛东部陆架的区域响应。     

Measurement of trace nitrate concentrations in seawater by ion chromatography with valve switching

An ion chromatographic method with a valve switching facility was developed to determine trace nitrate concentrations in seawater using two pumps, two different suppressors, and two columns. A carbohydrate membrane desalter was used to reduce the high concentrations of sodium salts in samples. In this method, trace nitrate was eluted from the concentrator column to the analytical columns, while the matrix flowed to waste. Neither chemical pre-treatment nor sample dilution was required. In the optimized separation conditions, the method showed good linearity （R〉0,99） in the 0.05 and 50 mg/L concentration range, and satisfactory repeatability （RSD〈5%, n=6）. The limit of detection for nitrate was 0.02 mg/L. Results showed that the valve switching system was suitable and practical for the determination of trace nitrate in seawater.     

Analysis of fatty acid composition of sea cucumber Apostichopus japonicus using multivariate statistics

Fatty acids （FAs） provide energy and also can be used to trace trophic relationships among organisms. Sea cucumber Apostichopus japonicus goes into a state of aestivation during warm summer months. We examined fatty acid profiles in aestivated and non-aestivated A. japonicus using multivariate analyses （PERMANOVA, MDS, ANOSIM, and SIMPER）. The results indicate that the fatty acid profiles of aestivated and non-aestivated sea cucumbers differed significantly. The FAs that were produced by bacteria and brown kelp contributed the most to the differences in the fatty acid composition of aestivated and non- aestivated sea cucumbers. Aestivated sea cucumbers may synthesize FAs from heterotrophic bacteria during early aestivation, and long chain FAs such as eicosapentaenoic （EPA） and docosahexaenoic acid （DHA） that produced from intestinal degradation, are digested during deep aestivation. Specific changes in the fatty acid composition of A. japonicus during aestivation needs more detailed study in the future.     

Effects of corridor networks on plant species composition and diversity in an intensive agriculture landscape

The development of modern agriculture has resulted in much homogenization of the landscape consisting of large patches of farmland,so small remnant non-crop habitats especially linear corridors play an important role in the conservation of species and the maintenance of ecosystem functions.However,little attention has been paid to the effects of corridors structural characteristics on the plant species restricted to such habitats.In this study,we selected three types of corridors including ditch,hedgerow and road,and ana-lyzed their structural characteristics.The plant species presented in these corridors were investigated,and the species diversity,abun-dance and frequency were estimated.Moreover,spatial arrangements of corridors were classified into different types to discuss whether there were significant effects of corridor network on plant distribution.The results show that three types of corridors have different ef-fects on plant species composition and diversity.The one-one combined corridor networks and total network associated by three corri-dors have more complex structural features than each single type of corridor.However,there is no strong correlation between the corri-dor networks with their plant species.We suggest that carrying out a pointed vegetation survey at corridor intersections to further test the relationships between structural features of corridor and plants is necessary.