外源Cd对小白菜吸收与分配Cd、Zn的影响

采用盆栽试验研究外加Cd处理下红沙泥田和乌栅土中小白菜(Brassica chinensis L.)[四月慢(SYM)和高梗白(GGB)]对Cd、Zn的吸收与分配规律.结果表明:(1)小白菜对Cd、Zn的吸收积累受土壤类型、蔬菜品种和外源Cd剂量的影响,四月慢吸收Cd能力比高梗白强,外加Cd处理、土壤、品种间的正交互作用使小白菜植株Cd/Zn比值提高;(2)小白菜食用部位Cd/Zn比值并不服从于植株对Cd、Zn的总吸收量之比,而是取决于其在根和地上食用部位中的分配,Cd的地上部分配系数为56.3%～71.1%,而Zn则为77.6%～80.6%.在一定Cd处理水平下,地上部Cd分配系数下降,而Zn分配系数无明显变化,从而减缓了Cd/Zn比值升高的趋势,使小白菜地上部受Cd毒害的风险性降低;(3)2种小白菜对Cd和Zn的吸收动态随生长时间不同而异,Cd积累量随时间延长呈不断增加趋势,而对Zn的吸收积累能力自苗期后缓慢降低.这种差异使小白菜生长后期Cd/Zn比值升高,从而提高了小白菜Cd暴露的潜在风险.此现象在红壤加Cd处理下表现尤其明显.     

柴油机尾气净化用的钙钛矿型催化剂的研究

用浸渍法制备了多种ABO_3型催化剂,考察了多种因素对其活性的影响及作用机制。柴油机台架实验结果表明,在A位掺杂Sr可提高催化剂的活性;稀土在最后一次浸渍液中浸渍,以二次浸渍为宜;堇青石陶瓷蜂窝状催化剂的性能优于γ-Al_2O_3球状催化剂。蜂窝状催化剂上CO的起燃温度T_(50)％=110℃,而T_(90)％=157℃;在温度仅为200℃,而空速高达70000h~(-1)的条件下CO的净化率仍达90％;积碳起燃温度为323℃,优于Pt族贵金属催化剂;热稳定性和对CO浓度的适应性较好,且具有抗SO_2中毒能力。     

改进蒸发碱洗工艺的探讨

主要介绍了改进蒸发装置碱洗工艺的情况，为腈纶生产降低能耗、推行清洁生产开创了先例     

双震型序列第二主震的预测指标研究

根据15个中国大陆M_s≥5级双震型地震序列的资料,对双震型地震序列的活动过程和序列特征进行了分析,从h值(或P值)、密集—平静、震源机制、序列早期活动峰值的有序性等几个方面对第二主震的时间预报问题进行了探讨。     

土地处理过程中主要污染物对地下水污染的数学模拟方法讨论

本文通过对地下水水质数学模拟方法讨论,介绍了主要污染物在土地处理系统中的迁移转化过程概况,根据不同类型污染物特性,边界条件及污水排放形式,建立起相应的模型解析方程,并确定有关参数值,试图从量上来预测污染物浓度在地下水流中的时空变化规律。     

生活垃圾高温空气气化处理的低污染特性分析

本文介绍了高温空气气化城市生活垃圾的工作原理及过程 ,分析了城市生活垃圾高温气化反应机理。通过对高温空气 /蒸汽发生器、高温气化炉及湿式除尘器等关键部件的分析发现 ,采用高温空气气化系统可实现城市生活垃圾低污染处理     

牡丹江市生态环境质量分析

运用RS/GIS(遥感)技术、GPS技术与实地监测相结合的方法,以环境统计数据为基础,对牡丹江市生态环境质量状况进行评价分析。     

Modeling carbon sequestration under zero-tillage at the regional scale. II. The influence of crop rotation and soil type

For policy decisions with respect to CO₂-mitigation measures in the agricultural sector, national and regional estimations of the efficiency of such measures are required. The conversion of ploughed cropland to zero-tillage is discussed as an option to reduce CO₂ emissions and promises at the same time effective soil and water conservation. Based on the upscaling of simulation results with the soil and land resources information system SLISYS-BW, estimations of CO₂-mitigation rates in relation to crop rotations and soil type have been made for the state of Baden-Württemberg (Germany). The results indicate considerable differences in the CO₂-mitigation rates between crop rotations ranging from 0.48 to 0.03 Mg C ha⁻¹ a⁻¹ for winter cereals–spring cereals–rape rotations and winter cereals–spring cereals–corn silage rotations, respectively. The efficiency of the crop rotations is strongly related to the total carbon input and in particular the amount of crop residues. Among the considered soil types, highest CO₂-mitigation rates are associated with Cumulic Anthrosols (0.62 Mg C ha⁻¹ a⁻¹) and the lowest with Gleysols (−0.01 Mg C ha⁻¹ a⁻¹). An agricultural extensification scenario with conventional plowing but conversion of the presently applied intensive crop rotations to a clover–clover–winter cereals rotation indicated a CO₂-mitigation potential of 466 Gg C a⁻¹. However, the present high market prices for cereals and increasing demand for energy production from biomass encourages an intensification of the agricultural production and an excessive removal of biomass which in future will seriously reduce the potential for carbon sequestration on cropland.