内蒙古草原温室气体排放日变化规律研究   总被引：11，自引：0，他引：11  

胡玉琼  王跃思  纪宝明  王明星  杜睿 《南京气象学院学报》2003,26(1):29-37

采用静态值－气相色谱法研究内蒙古草原温室气体N2O、CO2、CH4与大气交换的日变化规律。CO2日排放变化形式基本相同，和大气交换的总结果是向大气排放，影响草原N2O排放日变化形式的关键是土壤含水量和表层土壤理化特性，日温变化主要影响其日变化强度；影响草原CH4日变化形式的关键因子是土壤水分和供氧状况，而温度和植物的生长状况则影响吸收强度，利用内蒙古草原温室气候排放相对固定的日变化形式，可以对相同生产季内每周1次的观测结果进行矫正。  相似文献   

甲醛还原Pt/TiO₂催化剂用于温和条件下高效催化氧化甲醛（英文）     

陈铧耀  芮泽宝  纪红兵 《甘肃地质》1997,(1):188-196

通过浸渍法(IM)和沉积-沉淀(DP)法制备了一系列Pt/TiO2P25)催化剂,并分别用甲醛溶液和氢气还原处理催化剂.利用原位红外监测催化剂表面吸附物种在反应过程中的变化,探究了催化剂制备和还原条件及Pt负载量对催化剂结构和催化氧化甲醛活性的影响.结果显示,用DP法制备并用甲醛还原的Pt/P25催化剂中Pt颗粒分散均匀,并具有合适的粒径和高浓度的表面活性氧,显示出良好的甲醛氧化活性.在空速30 000 ml/(g·h)、反应温度30°C和甲醛初始浓度50 mg/m的条件下,0.4%Pt/P25(DP-HCHO)上的甲醛转化率达到98%,并能稳定运行100 h以上.相比之下,Pt/P25(DP-H2)由于表面活性氧较少,不利于甲酸盐氧化,活性较低.Pt/P25(IM-H2)虽然具有高浓度的表面活性氧,却同时具有最大的Pt颗粒粒径,在甲醛转化为甲酸盐和甲酸盐氧化两步反应中的活性均较差,因而甲醛氧化活性最差.  相似文献   

松潘—甘孜造山带中巴西金-矽卡岩矿床成矿热液系统演化的(REE、Sr、O)证据   总被引：2，自引：0，他引：2  

季宏兵  王世杰  李朝阳  文锦明 《矿物学报》1997,(4)

本文通过对巴西典型金-矽卡岩矿床的解剖，探讨了成矿流体来源、组成演化，以及流体和岩石之间的质量转移程度和机理的信息，揭示金成矿过程中成矿流体演化的规律。研究认为，成矿作用两阶段的成矿流体分别为变质流体和大气降水，它们在开放系统中水岩质量比分别为0．02，2．11，并且获得矽卡岩可能是由围岩转向岩体方向的变质流体交代形成的认识。  相似文献   

Geochemistry of the Jinman Vein—Type Copper Deposit,Western Yunnan Province,China——I.Element Geochemical Characteristics   总被引：3，自引：0，他引：3  

季宏兵  李朝阳 《中国地球化学学报》1996,15(2):172-184

The Jinman copper deposit,which is situated on the northern margin of the Lanping-Simao back-arc basin,western Yunnan Province,is a silver-bearing,high-grade vein-type copper deposit.Comprehensive element geochemical studies of the host rocks and hydrothermal minerals revealed the regularities in the distribution,mobilization and transport of elements from the host rocks to hydrothermal minerals.In conjunction with the fluid inclusion and isotope data,it is suggested that the ore-forming fluid was derived mainly from a deep source characterized by CO2 enrichment and reduction in nature.It is also suggested that the oreforming materials come largely from a deep source.although the contribution of the country rocks should not be ruled out.It is also found that some hydrothermal minerals are possessed of MREE-enrichment patterns.It is deduced that the REEs in the deep-source ore fluid were transported in the form of CO3^2- complexes and were deposited in a continental basin(or a hot-spring basin).  相似文献   

Geochemistry of Brines from Salt Ore Deposits in Western Tarim Basin   总被引：2，自引：0，他引：2  

马万栋  马海州  谭红兵  董亚萍  张西营  孙国芳 《中国地球化学学报》2004,23(3):238-244

In the geological evolution of the Tarim Basin, many transgressions and relictions happened. So there have been plentiful sources of salt. Moreover, because of uttermost drought, a lot of salt has been deposited. It is possible to find potash salt in this area. In our fieldwork, we have found salt and brine in western Tarim Basin. Based on a geological survey and the characteristics of sedimentary facies and paleogeography, this paper deals with the geochemical parameters and discusses the possibility of formation of potash salt in terms of the chemical analyses of samples collected from western Tarim Basin. Results of brine analysis lead to some conclusions: most of these salt brines have eluviated from very thick halite beds, mainly chloridetype salt and this kind of halite does not reach the stage of potash deposition in all aspects; WKSL (Wukeshalu) occupies a noticeable place, and we should attach importance to this district because there have been some indicators of the occurrence of potash deposits as viewed from the contents of Br and K. Finally, low Br contents are recognized in the Tarim Basin as a result of salt aggradation, and this point of view has been proved by the results of this experiment and the data available. It cannot depend upon the index of Br to judge the evolution stage of halite. We must look for other facies of potash except marine facies.  相似文献   

辽西义县组奔龙类化石一新种   总被引：4，自引：1，他引：4  

刘金远  姬书安唐烽　高春玲 《地质通报》2004,23(8):778-783

在辽宁西部义县头台的义县组中新发现的1件奔龙类化石标本，显示出许多中国鸟龙属(Sinornithosaurus)所具有的特征，如上颌骨眶前窝侧面具有装饰性凹坑、前颌骨齿无边缘小锯齿、齿骨后缘二分叉、指节Ⅲ-1略长于指节Ⅲ-2的2倍、踱骨Ⅲ部分窄踱型形态等。但其头骨的部分骨骼与千禧中国鸟龙(S．millenii)有明显的区别：前颌骨主体部分相对较高，其长仅稍大于其高，前颌骨角大，前颌骨上颌突与鼻突均很长，上颌骨不参与外鼻孔的构成，上颌骨窗相对较小且为圆形，方颧骨上升突明显长于颧骨突，齿骨长高之比小等。此外，新标本肠骨的耻骨柄前后方向的宽度小于髋臼宽度。这些不同之处表明，义县头台的标本应为中国鸟龙属另一新种，将其命名为郝氏中国鸟龙(新种)(S．haoiana sp．nov.)。  相似文献   

黔西南下——中三叠统界线年龄   总被引：2，自引：3，他引：2  

王彦斌  刘敦一  姚建新  纪占胜  王立亭  武桂春 《地质学报》2004,78(5):586-590,i003

下—中三叠统界线年龄的精确测定是进行区域地层年表和国际地层委员会全球标准年表研究中重要的组成部分。中国贵州望谟甘河桥剖面下—中三叠统地层为奥仑尼克阶—安尼阶界线层型的理想候选剖面 ,其临界层位的玻屑凝灰岩为下—中三叠统界线的岩性标志。应用高精度高灵敏度的二次离子探针质谱对玻屑凝灰岩中的锆石进行 U- Pb年代学分析 ,结果为 2 39.0± 2 .9Ma(2σ)。这是首次直接从界线层位准确测定的下—中三叠统界线的锆石 U - Pb同位素年龄。中国贵州望谟甘河桥剖面下—中三叠统界线剖面地层连续 ,牙形石分带清楚 ,临界层位发育区域上分布较为稳定的玻屑凝灰岩 ,是极好的区域等时标志层。这一剖面有望成为国际下—中三叠统界线层型剖面。  相似文献   

Depositional sequence architecture and filling response model of the Cretaceous in the Kuqa depression, the Tarim basin   总被引：1，自引：0，他引：1  

Lin Changsong  WANG Qinghua  XIAO Jianxin  Wang Guolin  Liu Jingyan  JI Yunlong 《中国科学D辑(英文版)》2004,47(Z2)

The Cretaceous system of the Kuqa depression is a regional scale (second order) depositional sequence defined by parallel unconformities or minor angular unconformities. It can be divided into four third-order sequence sets, eleven third-order sequences and tens of fourth- and fifth-order sequences. It consists generally of a regional depositional cycle from transgression to regression and is composed of three sets of facies associations: alluvial-fluvial, braided river-deltaic and lacustrine-deltaic facies associations. They represent the lowstand, transgressive and highstand facies tracts within the second-order sequence. The tectonic subsidence curve reconstructed by backstripping technique revealed that the Cretaceous Kuqa depression underwent a subsidence history from early accelerated subsidence, middle rapid subsidence and final slower subsidence phases during the Cretaceous time, with the correspondent tectonic subsidence rates being 30-35 m/Ma, 40-45 m/Ma and 5-10 m/Ma obtained from northern foredeep. This is likely attributed to the foreland dynamic process from early thrust flexural subsidence to late stress relaxation and erosion rebound uplift. The entire sedimentary history and the development of the three facies tracts are a response to the basin subsidence process. The slower subsidence foreland gentle slope was a favorable setting for the formation of braided fluvial deltaic systems during the late period of the Cretaceous, which comprise the important sandstone reservoirs in the depression. Sediment records of impermanent marine transgression were discovered in the Cretaceous and the major marine horizons are correctable to the highstands of the global sea level during the period.  相似文献   

ATEM-Ⅱ型瞬变电磁系统的实际应用   总被引：1，自引：0，他引：1  

林君  嵇艳鞠  于生宝  王忠  王静  王艳  周国华  吴国强 《物探与化探》2004,28(6):496-499

介绍了ATEM-II型瞬变电磁系统在矿产普查、大型矿山潜力资源探查、地下水勘察、城市工程勘察和地下活断层调查、矿井透水预测等领域的应用实例.  相似文献   

洪水保险债券的运作机制与发展思路          下载免费PDF全文

魏敏杰  纪昌明 《水科学进展》2004,15(1):113-116

由于传统(再)保险,难以将洪灾风险进行有效的分散,因此,有必要寻求有效的金融工具将洪灾风险向资本市场转移。在建立洪水保险债券的概念框架基础上,阐述了与普通债券及传统再保险的区别。从经济学和精算学的角度对洪水保险债券进行分析,揭示了洪水保险债券定价机制。通过研究洪水保险债券的运作模式,分析了我国洪水保险债券的发行条件与发展思路,指出洪水保险债券为我国防洪减灾提供了可资借鉴的崭新方法与工具。  相似文献