Gaseous emissions from compressed natural gas buses in urban road and highway tests in China

The natural gas vehicle market is rapidly developing throughout the world, and the majority of such vehicles operate on compressed natural gas(CNG). However, most studies on the emission characteristics of CNG vehicles rely on laboratory chassis dynamometer measurements, which do not accurately represent actual road driving conditions. To further investigate the emission characteristics of CNG vehicles, two CNG city buses and two CNG coaches were tested on public urban roads and highway sections. Our results show that when speeds of 0–10 km/hr were increased to 10–20 km/hr, the CO_2, CO, nitrogen oxide(NO_x), and total hydrocarbon(THC) emission factors decreased by(71.6 ± 4.3)%,(65.6 ± 9.5)%,(64.9 ± 9.2)% and(67.8 ± 0.3)%, respectively. In this study, The Beijing city buses with stricter emission standards(Euro Ⅳ) did not have lower emission factors than the Chongqing coaches with Euro Ⅱ emission standards. Both the higher emission factors at 0–10 km/hr speeds and the higher percentage of driving in the low-speed regime during the entire road cycle may have contributed to the higher CO_2 and CO emission factors of these city buses. Additionally, compared with the emission factors produced in the urban road tests, the CO emission factors of the CNG buses in highway tests decreased the most(by 83.2%), followed by the THC emission factors, which decreased by 67.1%.     

特种作业人员存在的问题及解决办法初探

例举了武钢金山店铁矿特种作业人员中存在的问题,提出了相应的解决办法。     

绿色导向下的光伏产业环境污染控制进展研究

光伏发电技术具有环保和节约能源的特点,在光伏组件废弃后和太阳能电池的原料生产环节,会产生一定程度的环境污染.对太阳能电池废弃物进行资源化回收处理,积极研发新型电池和新材料,可以有效控制污染.目前对光伏废弃物进行资源化的方法主要有:热解法,无机酸溶解法,有机溶剂溶解法,化学蚀刻等;薄膜型光伏电池和聚合物光伏新材料的研究也取得了相应进展,拥有较好的发展前景.     

用四-(对氨基苯基)-卟啉柱前衍生的高效液相色谱法测定重金属

研究了用固相萃取富集、快速分离柱高效液相色谱法测定环境水样中镍、锡、铅、镉、汞5种重金属的方法。环境水样中的镍、锡、铅、镉、汞用四-(对氨基苯基)-卟啉(T4APP)柱前衍生,然后用ZORBAX RP18固相萃取小柱萃取富集镍、锡、铅、镉、汞的T4APP络合物,经富集后的络合物用甲醇-丙酮(体积比95∶5)为流动相,ZORBAX Stab le Bound(4.6 mm×50 mm,1.8μm)快速分离柱为固定相分离,用二极管矩阵检测器检测。镍、锡、铅、镉、汞的检测限分别为4,5,4,3,3 ng/L,分离5种重金属元素络合物的时间只需2.0 m in,相对标准偏差为2.2%~4.1%,加标回收率为88%~104%。用该法测定环境水样中的痕量镍、锡、铅、镉、汞,结果令人满意。     

垃圾填埋场渗滤液性质研究进展

从宏观、中观和微观三个尺度对目前垃圾填埋场渗滤液的性质、处理方法和研究手段进行了系列介绍与比较。比较结果表明．相对于宏观和微观尺度的渗滤液性质的研究,中观尺度的研究将更有助于指导渗滤液处理工艺的发展方向。     

老港填埋场渗滤液性质随工艺变化研究

经老港填埋场渗滤液处理系统的各处理单元处理后的流出液,用不同孔径的系列膜进行了梯度分离。分离前后的渗滤液进行了TOC、TP、TN、氨氮和可溶性P等参数的测定,并建立了各参数与不同孔径膜的关系。结果表明,此工艺对老港填埋场渗滤液的处理具有一定的功效;随着处理工艺的进行,渗滤液的组成发生了较大的改变,其中细胶体部分的百分含量增加,而可溶性部分降低;渗滤液的绝大部分污染物质集中于可溶性部分,而渗滤液中的P主要与大分子的悬浮物和粗胶体结合。     

微生物絮凝剂产生菌的筛选

从废水、土壤、活性污泥中筛选到2株絮凝剂产生菌。参照伯杰氏手册进行菌种分类鉴定,初步确定均属氮单胞菌属（Azomonas sp.)。将Azomonas sp.在产絮凝剂的培养基中进行发酵培养后,测定其对高岭土悬浮液的絮凝活性。废水絮凝实验表明,该菌种所产絮凝剂絮凝效果明显,可絮凝各种水溶液中的悬浮物质。     

MATLAB在脱硫反应器设计中的应用

介绍了强大的数值分析软件ＭＡＴＬＡＢ在脱硫反应器设计中的应用。通过计算反应器内部静态电场,比较了线板式、线筒式、线线式反应器中的电场分布,从而可以选择较优的反应器结构。     

绿色技术评价磺化反应过程热危险性

反应量热仪RC1研究磺化反应过程中热危险性具有评价路线简单、易于操作、过程绿色环保等优势,近年来逐渐成为研究的热点.磺化反应过程中由于工艺的不同,不同磺化反应过程的热危险性也具有很大的差别.通过反应量热仪RC1、差示扫描量热DSC、绝热加速量热仪ARC对10种不同工艺的磺化反应过程的热危险进行了深入的研究,对企业实践生...     

Biochar reduces cadmium accumulation in rice grains in a tungsten mining area-field experiment: effects of biochar type and dosage,rice variety,and pollution level

Environmental Geochemistry and Health - Cadmium (Cd)-contaminated rice (Oryza sativa) in Southern China is a great threat to food security, and the paddy soil remediation is urgently needed to...