南岳森林土壤的研究——Ⅱ.化学性状和土壤有机质

本文介绍了南岳森林土壤与母岩的化学性状,以了解气候和植被对土壤的影响;介绍了土壤有机质的作用、含量、分布;讨论了影响土壤有机质含量的因素并给出了循环模型。     

Informing global environmental policy‐making: A plea for new methods of assessment and synthesis

Practice and research in assessment of global environmental change are dominated by two conventional assessment methods, formal models and expert panels. Models construct a representation of biophysical and socioM48U67830/xxlarge8208.gif" alt="dash" align="MIDDLE" BORDER="0">economic components of a policy issue, to project future trends or consequences of interventions. Panels articulate consensus views of policyM48U67830/xxlarge8208.gif" alt="dash" align="MIDDLE" BORDER="0">relevant knowledge through deliberations among selected experts. These methods make valuable contributions, but are weak in addressing certain kinds of knowledge needs that are typical of globalM48U67830/xxlarge8208.gif" alt="dash" align="MIDDLE" BORDER="0">change issues. To address these needs, a set of novel assessment methods is proposed that combine elements of representation and deliberation. These methods, of which policy exercises, simulationM48U67830/xxlarge8208.gif" alt="dash" align="MIDDLE" BORDER="0">gaming, and scenario exercises are examples, involve human participants in structured relevant decision and task settings. Relative to models and panels, these methods can more readily incorporate diverse perspectives, can integrate across broader collections of knowledge domains, and can both encourage creative insights and innovations, and provide tests of their relevance and practicality. Risks of bias, and of overM48U67830/xxlarge8208.gif" alt="dash" align="MIDDLE" BORDER="0">confident generalization from unique experiences, are effectively mitigated by critical debriefings, and appear no more severe than corresponding risks in conventional assessment methods, or in policyM48U67830/xxlarge8208.gif" alt="dash" align="MIDDLE" BORDER="0">makersM48U67830/xxlarge8217.gif" alt="rsquo" align="BASELINE" BORDER="0"> generalizations from historical experience. While serious development and implementation challenges remain, early experience suggests that these methods can offer useful ideas and insights for policyM48U67830/xxlarge8208.gif" alt="dash" align="MIDDLE" BORDER="0">making that are not available through other means.     

Geochronology and geochemistry of eclogites from the Mariánské Lázne Complex, Czech Republic: Implications for Variscan orogenesis

The Mariánské LáznM870K21588067504/xxlarge283.gif" alt="ecaron" align="BASELINE" border="0"> complex (MLC) is located in the Bohemian Massif along the north-western margin of the Teplá-Barrandian microplate and consists of metagabbro, amphibolite and eclogite, with subordinate amounts of serpentinite, felsic gneiss and calcsilicate rocks. The MLC is interpreted as a metaophiolite complex that marks the suture zone between the Saxothuringian rocks to the north-west and the Teplá-Barrandian microplate to the south-east. Sm-Nd geochronology of garnet-omphacite pairs from two eclogite samples yields ages of 377±7, and 367±4 Ma. Samples of eclogite and amphibolite do not define a whole rock Sm-Nd isochron, even though there is a large range in Sm/Nd ratio, implying that the suite of samples may not be cogenetic. Eclogites do not have correlated ^{M870K21588067504/xxlarge603.gif" alt="epsiv" align="BASELINE" border="0">} _Nd values and initial ⁸⁷Sr/⁸⁶Sr ratios. Five of the eight eclogite samples have high ^{M870K21588067504/xxlarge603.gif" alt="epsiv" align="BASELINE" border="0">} _Nd values (+10.2 to +7.1) consistent with derivation from a MORB-like source, but variable ⁸⁷Sr/⁸⁶Sr ratios (0.7033 to 0.7059) which probably reflect hydrothermal seawater alteration. Three other eclogite samples have lower M870K21588067504/xxlarge603.gif" alt="epsiv" align="BASELINE" border="0">_Nd values (+ 5.4 to –0.8) and widely variable ⁸⁷Sr/⁸⁶Sr ratios (0.7033 to 0.7096). Such low M870K21588067504/xxlarge603.gif" alt="epsiv" align="BASELINE" border="0">_Nd values are inconsistent with derivation from a MORB, source and may reflect a subduction or oceanic island basalt component in their source. The MLC is an important petrotectonic element in the Bohemian Massif, providing evidence for Cambro-Ordovician formation of oceanic crust and interaction with seawater, Late Devonian (Frasnian-Famennian) high- and medium-pressure metamorphism related to closure of a Saxothuringian ocean basin, Early Carboniferous (Viséan) thrusting of the Teplá terrane over Saxothuringian rocks and Late Viséan extension.     

Chemical forms of cobalt and nickel extracted by M1,M3 and CaCl_2-DTPA

ＣｈｅｍｉｃａｌｆｏｒｍｓｏｆｃｏｂａｌｔａｎｄｎｉｃｋｅｌｅｘｔｒａｃｔｅｄｂｙＭ１，Ｍ３ａｎｄＣａＣｌ２ＤＴＰＡＷｅｎＢｅｉ，ＱｉａｎＪｉｎ，ＣｈｅｎＢｉｎ，ＳｈａｎＸｉａｏｑｕａｎＲｅｓｅａｒｃｈＣｅｎｔｅｒｆｏｒＥｃｏＥｎｖｉｒｏｎ...     

聚合物／改性白泥纳米复合材料研究与应用

白泥是造纸碱回收的废渣，国内外对造纸碱回收白泥的回收和再利用有了一定的研究，但由于技术问题和回收成本较高等原因，对白泥有效利用问题没能彻底的解决。我们在总结了目前国内外白泥回收现有技术状况的基础上，着重对白泥与聚合物共混制功能材料方面进行了相应的分析和研究，通过对白泥的改性处理并与聚合物共混制得高级别的聚合物／改性白泥纳米复合材料．扩大了回收白泥的应用领域和范围，降低了白泥的回收成本，并有效解决了白泥再利用问题。     

苏丹M盆地原油地球化学特征与母质的沉积环境探讨

通过对苏丹M盆地萨加隆起带的原油地球化学特征分析 ,探讨了生成原油的烃源岩的母质的沉积环境。该带原油主要有两种类型 ,一种是正常原油 ,另一种是生物降解油。原油的地球化学特征表明 :正常原油具有较高的饱和烃含量 ,生物降解原油饱和烃含量低 ,非烃含量高 ;碳同位素表明为典型的湖相Ⅰ Ⅱ有机质生成的原油 ;原油饱和烃具有较低的异戊二稀烃 ,Pr/Ph一般在 1.5左右 ,表现为弱的姥鲛烷优势 ,具有较完整的重排甾烷和新藿烷系列 ,γ蜡烷含量较低 ;重排甾烷含量高 ,C2 7、C2 8、C2 9甾烷呈“V”字型分布 ,具有较丰富的4 甲基甾烷。原油地球化学指标显示主要的烃源岩为弱氧化—弱还原、淡水—微咸水的沉积环境 ,有机质为水生生物和细菌改造的陆源有机质的混合输入 ,为一种以生油为主生气较少的母质类型。     

机动车排气检测与维修有关问题的探讨

分析了机动车排气检测与维修的现状及存在问题 ,并提出建设有中国特色的I/M管理制度。     

Amniotic fluid microvillar enzyme activities in the early detection of fetal abnormalities

Measurement of the microvillar enzymes, γ-glutamyltranspeptidase (GGTP), aminopeptidase M (APM) and alkaline phosphatase (ALP), in amniotic fluid supernatant has been proposed as a method for the early prenatal diagnosis of cystic fibrosis. The activities of these enzymes in a series of other fetal abnormalities have now been examined. GGTP activities were below the 5th percentile in 28 out of 54 cases of trisomy 21 and 9 of 14 cases of trisomy 18, while APM values were below this cut-off in 26 of 54 cases of trisomy 21 and 8 of 14 cases of trisomy 18. Abnormal ALP isoenzyme ratios were found in 6 of 54 cases of trisomy 21 and 4 of 14 cases of trisomy 18. If prenatal cytogenetic studies are routinely carried out on amniotic fluid cells, the occasional confounding effect of abnormal microvillar enzymes associated with fetal trisomies rather than with cystic fibrosis should be avoided.     

上海市在用车I／M计划管理体系的探讨

在用机动车监测与维修制度（I／M计划）是减少机动车污染排放的最主要措施。借鉴美国I／M计划取得的经验，提出上海市在用车I／M 计划管理体系，建立上海市I／M 计划管理中心和监测 中心。     

Influences of accumulated mileage and technological changes on emissions of regulated pollutants from gasoline passenger vehicles

In this study, the influences of accumulated mileage(deterioration) and technological changes(emission standards) on emission factors(EFs) of regulated pollutants(CO, HC, and NO_x) from gasoline passenger vehicles were investigated based on Inspection and Maintenance(I/M) data using the chassis dynamometer method. The accumulated mileage of passenger vehicles was significantly linearly correlated with vehicle age. For most cases,the average EFs of CO, HC and NO_x were significantly linearly correlated with accumulated mileage, indicating that emission deterioration had a significant impact on pollutant EFs.Implemented emission standards markedly influenced the EFs of regulated pollutants, and EFs markedly decreased with progressing emission standards. The present study also compared EFs of regulated pollutants between this study and the International vehicle emission(IVE) model, and marked differences in EFs were seen with variations in emission standards, vehicle types and accumulated mileage; NO_x EFs in this study were higher than in the IVE model. The results provide new insight into estimating regulated pollutant emissions using the IVE model.