中国南方寒武—奥陶纪大陆斜坡的特征、演化和有关矿产

寒武—奥陶纪,中国南方发育着一个壮观的大陆斜坡。斜坡规模长约二干多公里、宽几十至几百公里,在其范围内,拥有各种各样的大中小型金属和非金属矿床,特别是磷、钒、钡、钼、镍、铜、金、银、锰、石煤和油气。据研究:该斜坡带有八大类沉积物类型即岩崩、滑移、滑塌沉积等和三种横向沉积模式,所谓缓坡、加积型边缘和跌积型边缘,还有四种垂向演化类型,即推进式、后退式、直立式、淹没式。斜坡带的生物群落属台地和盆地的混合型,或者互相渗透的过渡型,此外,尚有一些特有的生物种属和遗迹化石。该斜坡带有沉积单斜构造、重力滑动构造、同沉积断裂构造和隆起构造四种重要的构造形式。 寒武—奥陶纪华南不存在“江南古陆”,应为一长期持续下降的深水斜坡一陆隆环境。华南古大陆边缘曾经历了裂谷作用(?—Z_1)、被动大陆边缘(Z_2—O_1)和闭合造山(O_2—S)三个阶段。作者对斜坡带中的沉积磷矿、重品石矿、石煤矿、锰矿、金银矿化层及油气资源进行了分析和探讨,指出华南古大陆斜坡带是十分有利的成矿域。     

Kinetic analysis of photocatalytic oxidation of gas-phase formaldehyde over titanium dioxide

Degradation of formaldehyde with different initial concentration over titanium dioxide was carried out in a photocatalytic reactor. Photocatalytic rates were well described by the simplified Langmuir-Hinshelwood model. The kinetic analysis shows that the apparent first-order reaction coefficient is lower and half-life of photocatalysis is longer for low concentration than for high concentration formaldehyde. A network formation model of the photocatalytic products was established. Experimental results and analysis demonstrate that carbon dioxide concentration and carbon monoxide concentration in gas phase vary exponentially with the illumination time and may be even higher than gas-phase formaldehyde concentration if there is much pre-adsorbed formaldehyde in adsorption equilibrium on catalysts before illumination. Carbon monoxide is found to be one of the by-products during formaldehyde photooxidation.     

Au/SnO2催化氧化CO性能的研究

以SnO₂为载体，Au为活性组分，采用真空浸渍法、共沉淀法、沉积沉淀法制备CO氧化的催化剂，同时还制备双金属体系催化剂Au-Pd/SnO₂和Au-Pt/SnO₂。用气相色谱对所制备的催化剂进行活性评价，运用DSC、SEM、XRD、BET等对催化剂进行表征。在本实验条件下，载体二氧化锡焙烧温度为500 ℃，催化剂成型温度为350 ℃，金负载量为3%(wt.)时，用沉积-沉淀法制备的Au/SnO₂活性最好，在18 ℃，空速为24 000 h-1条件下就能将CO（浓度为4%）完全氧化为CO₂；添加铂和钯可提高Au/SnO₂对CO的催化活性。     

Movement of bromacil and hexazinone in soils of Hawaiian pineapple fields

Bromacil and hexazinone have been heavily used to control weeds in the pineapple fields in central Oahu, Hawaii, USA, since 1970s and 1980s, respectively. The last application prior to this study was at a rate of 0.6 kg active ingredient (a.i.) ha(-1) for hexazinone and 1.8 or 3.4 kg (a.i.) ha(-1) for bromacil in the six study fields during June-October 1998. Soils were collected from 0 to 1860 cm below the surface in January-May 1999 to survey the residue profiles of the two herbicides. Stratoprobe sampling showed to be an efficient and convenient method for deep soil cores. Bromacil was detected in all the soil samples above 60 cm (105-1338 ng g(-1) dry weight) and in 74% of the samples above 400 cm (26-473 ng g(-1)). Trace amounts of bromacil (90-113 ng g(-1)) were detected in some of the samples collected from as deep as 1540 cm. Hexazinone was detected in three of the six fields at 0-60 cm only (86-107 ng g(-1) dry weight). The more frequent detection of bromacil at higher concentrations than hexazinone is related to the prolonged higher application rates of bromacil in the fields and its higher persistence and mobility in soil.     

络合萃取法处理5-氯水杨酸生产废水的研究与实践

采用络合萃取法处理5-氯水杨酸生产废水,研究了萃取过程中PH、络合剂、稀释剂等对废水革取效果的影响。通过比较,确定以EPT-1为络合剂。试验表明,pH<1.5,按废水:络合剂:稀释剂-100:30:70的比例投加,可取得较好效果。萃取剂连续使用15次,废水的CODCr去除率并无显著下降。多次萃取后萃取剂经氢氧化钠溶液反萃取再生,即可回收萃取剂。     

除尘脱硫系统带水原因及解决对策

对燃煤烟气除尘脱硫系统容易产生引风机带水问题进行了分析和研究，改进了传统的除尘脱硫器水位控制箱和溢水槽，有效解决了常用的冲击水浴式和旋风水膜式除尘脱硫系统风机带水问题。     

宁波地区海产品中汞污染现状研究

采用冷原子吸收（荧光）法测定了宁波不同地区的各种海产品中总汞和甲基汞含量，总体属轻度及中等污染水平，工业轻发达地区的海产品内总汞和甲基汞的含量较高，不同种类海产品因食性不同，在食物链中所处位置不同，表现为贝壳类＞肉食性类＞杂食性类＞植食性类＞藻类和水草，无鳞鱼类＞有鳞鱼类；海产品中不同部分污染水平表现为内脏＞头部＞肌肉；海水＜底泥＜海产品。除个别样品接近国家标准外，其余都符合我国食品卫生标准。     

大气微生物粒子与飘尘粒子的关系

用ＡＮＤＥＲＳＥＮ生物粒子采样器和光散射气溶胶粒子计数器，在北京西单对大气细菌、真菌和飘尘粒子的浓度、粒度分布及它们之间的关系进行了观测和研究。结果表明，大气细菌的粒度是负偏态分布，大气真菌是对数正态分布，飘尘是正偏态分布。大气细菌浓度与飘尘浓度的比值冬季大，为１１９５３８；夏季小，为２４２１７；年平均比值为６７５１７，＞２．０μｍ的菌尘比值为１５２５３８７，２．０μｍ～８．２μｍ的菌尘比值为３３１８，＞８．２μｍ的菌尘比值为３９４。大气真菌浓度与飘尘浓度的比值冬季大，为２１２７７０；夏季小，为６５５８５；年平均比值为１３５３４４，＜２．０μｍ的菌尘比值为９５２６９８，２．０μｍ～８．２μｍ的菌尘比值为５３４３，＞８．２μｍ的菌尘比值为２６３２。     

臭氧氧化降解三唑酮的试验

在利用O3/H2O2体系氧化三唑酮的基础上,探讨了O3氧化三唑酮的最佳反应条件和水中杂质对氧化反应的影响,并对氧化产物进行了分析.研究结果表明,三唑酮浓度为3mg·L-1、臭氧浓度为25mg·L-1、室温(26℃)、pH值为7～8条件下,三唑酮去除率最高可达94.1%;腐殖酸对三唑酮的降解表现为低浓度促进、高浓度抑制,HCO-3对三唑酮降解的抑制作用较小;伴随三唑酮的降解,体系pH下降.色谱分析结果表明,三唑酮首先被氧化为1,2,4-三唑、对氯苯酚和酸性产物,最终生成NO-3、Cl-、CO2和H2O小分子,降解比较彻底.