黄土丘陵区土壤抗水蚀能力变化的动态评估

以黄土丘陵区典型小流域纸坊沟为研究对象,建立了土壤抗水蚀能力动态评价的指标体系,利用层次分析法对1938～2000年间研究区域的土壤抗水蚀能力进行了动态评估。引入土壤相对抗水蚀能力指标,并采用生态系统健康和承载力相关概念,研究了流域土壤抗水蚀能力偏离理想状态程度的变化情况,分析了其健康状态变化、恢复力和可恢复程度;通过与土地利用结构状态变化过程与恢复特性的比较,揭示了土壤抗水蚀能力对于土地利用结构变化的响应关系,指出了响应曲线中的滞后特点并对其产生的原因进行了分析。研究结果与前人所得的结果吻合较好,说明研究中采用的方法能够有效预测土壤抗水蚀能力,也可为水土保持恢复和管理工作提供科学支持。     

现代垃圾填埋技术设计理念及其工程应用

对现代垃圾填埋技术的设计要点进行归纳,并结合上海市老港填埋场四期工程介绍其在工程设计中的具体应用。     

高锰酸钾及氯化锰对日本青鳉的急、慢性毒性(Toxic Effects of Potassium Permanganate and Manganese Chloride on the Early Life Stage of Japanese Medaka（Oryzias latipes）)

饮用水生产中投加高锰酸钾可能引起高锰酸钾及其副产物二价锰的毒性效应.利用日本青鳉的胚胎-幼鱼发育阶段评价了以高锰酸钾为预氧化剂的饮用水生产工艺安全性.结果表明,高锰酸钾对日本青鳉的LC50-96h为1.48mg·L-1.慢性暴露中,对孵化时间影响的最低可观察效应浓度(LOEC30d)为0.1mg·L-1;暴露于0.4mg·L-1的高锰酸钾对30d后日本青鳉的体长、体重、累计死亡率均有显著影响,但对孵化率率无显著影响.氯化锰(Mn2+)对日本青鳉的LC50-96h为550mg·L-1,对体重影响的LOEC30d为3.2mg·L-1.当高锰酸钾的使用浓度在0.5～1.5mg·L-1之间,其在滤后水中的高锰酸钾残余浓度低于检出限,而降解中间体产物Mn2+浓度小于0.5mg·L-1,均低于本文报道的LOECs数值.     

苦味酸钾在电引火元件生产中的应用研究

目前使用的工业电雷管的发火可靠性和一致性普遍不理想,并带来安全隐患和环境污染,原因之一是采用KClO3-C-DDNP系列引火药剂制造电引火元件.为探讨将苦味酸钾作为电引火元件引火药剂的可行性,通过理论分析和部分实验论证,对比分析了苦味酸钾引火药和DDNP引火药在热安定性、机械感度、生产和使用安全性、燃烧精度、发火可靠性和一致性、产品性能、制药废水处理等方面的差别.结果表明,在电引火元件制造中,采用苦味酸钾作为引火药剂的主要组分,在保证和控制产品质量,改善生产和使用的安全性,环境保护等方面都有明显改进,有利于提高电雷管的发火可靠性和一致性.     

酿酒酵母吸附Zn(Ⅱ)过程中阳离子(K+，Mg2+，Na+，Ca2+)的变化分析

研究了酿酒酵母无缓冲溶液体系吸附Zn(Ⅱ)的过程中各种阳离子的变化情况.研究结果表明,当Zn(Ⅱ)的初始浓度是0.08～0.8 mmol·L^-1,酵母浓度约1 g·L^-1,初始pH为5.65,反应38h内,酵母的Zn(Ⅱ)吸附量为74.8～654.8μmol·g^-1,去除率达到76.4%～92.8%,pH值升高0.55～1.28.吸附过程中酵母首先快速释放大量K⁺,其次是Mg²⁺和Na⁺,Ca²⁺的释放量较少,数量级一般可分别达到几百、几十和几个μmol·g^-1.以离子交换为基础计算的各阳离子释放量总和一般超过Zn(Ⅱ)的吸附量,证明酵母吸附Zn(Ⅱ)的机理之一是离子交换,但不唯一.无缓冲溶液体系酵母吸附Zn(Ⅱ)的过程中溶液pH值升高,H⁺被吸收,K⁺等阳离子释放,是生物体细胞的本质属性,与Zn(Ⅱ)是否存在无关,但是Zn(Ⅱ)可以促进阳离子的释放以及降低酵母对H+的吸收,也反映出Zn(Ⅱ)与H⁺之间可以竞争细胞表面吸附位.死酵母的吸附量低于未处理酵母,与阳离子交换能力关系不大,可能与细胞表面变形导致Zn(Ⅱ)吸附困难有关.     

HMP和SDS在KMnO4氧化水溶相PCE中的联合效应

利用KMnO₄原位化学氧化法处理污染地下水中的氯代烯烃已被证实有效可行,但是反应中产生的MnO₂沉淀会影响修复效果,延长修复时间. 采用KMnO₄氧化法处理水溶相的PCE(四氯乙烯),研究了添加HMP(六偏磷酸钠)和SDS(十二烷基磺酸钠)对该反应的联合效应. 结果表明,离子强度对MnO₂沉淀的生成影响显著,离子强度越高,MnO₂沉淀生成得越快. 在20℃, ρ(PCE)初始值为20mg/L,n(KMnO₄)∶n(PCE)为15∶1,离子强度为0.1mol/L的条件下,单独添加HMP可减少反应过程中MnO₂沉淀的产生,ρ(HMP)为0.1g/L的条件下,24h内没有产生MnO₂沉淀;单独添加SDS可增加Cl-生成量,在ρ(SDS)为1.0g/L的条件下,Cl-生成量增加了8.2%,但会增大MnO₂沉淀的生成速率;在同时添加HMP〔(ρ(HMP)为0.1g/L)〕和SDS〔(ρ(SDS)为1.0g/L)〕的条件下,Cl-生成量增加了7.5%,并且24h内没有产生MnO₂沉淀,表明二者同时添加既可提高PCE的去除率又可减缓MnO₂沉淀的生成.      

太湖流域农户环境友好型技术采纳行为及其环境和经济效应评价——以测土配方施肥技术为例

论文基于太湖流域上游地区221 户水稻生产农户调查数据,利用Probit 模型分析了农户采纳测土配方施肥技术的影响因素,然后构建投入需求和产出供给方程,评价了测土配方施肥技术采纳的环境和经济效应。研究表明,平均年龄越小、家庭耐用资产状况越好以及上一年与农技推广人员接触次数越多的农户,越倾向于选择测土配方施肥技术,而受教育年限较少或较多的农户都不愿意选择该技术。测土配方施肥技术确实能够起到降低化肥施用量和提高水稻产量的双重作用,控制其他条件,测土配方施肥技术采用率每增加1%,化肥施用量降低0.09%(0.45 kg/hm²),而水稻单产提高0.04%(2.91 kg/hm²)。若研究区域实现测土配方施肥全面推广应用,将可进一步减少化肥用量34.91 kg/hm²,同时提高水稻产量223.98 kg/hm²,具有较可观的环境和经济效应。但是测土配方施肥技术的实际推广进程缓慢,项目管理实施也不够规范,为此,有必要加大测土配方施肥技术研究投入,加强对技术的宣传和培训工作,同时结合示范户的榜样作用,以点带面促进该技术的深入推广和规范实施。     

Detection of metallothionein in the intestinal mucosa and brain with 109cadmium∗

Metallothionein (MT) has a great capacity of binding metal ions showing an interesting connection with metal toxicology, as a biochemical marker for environmental metal pollution.

To normal male Wistar rats (200±10 g) and other groups with ferropenic anemia, are administered 1 mg Cd/Kg/day, during 6 days, and MT labelled with the administration 2 h before sacrifice of 3 μCi ¹⁰⁹CdCl₂, also through intragastric catheter. The MT concentration in the intestinal mucosa is expressed in μg MT/g fresh tissue, being for control rats 1.4 ± 0.5; for rats administered with 6 doses of Cd 2.5 ± 0.6 (P<0.05); with ferropenic anemia 4.3±0.7 (P<0.001), and for anemic rats treated with 6 doses Cd 12 + 0,3 (P<0.001) μg MT/g fresh tissue respectively. PAGE 15% T, 2% C_Bis show for intestinal mucosa 2 MT peaks and for brain 3 MT peaks. Anemia induce MT accumulation and increases cadmium incorporation, being anemic subjects eligibles to be submitted first to control and detoxication than the rest of the population, and also MT should be studied as biochemical marker of the pollution.     

The occurrence of disinfection by‐products in Taiwan drinking water

In this study, samples were taken from six conventional water treatment plants for disinfection by‐products analysis. Results from the analysis revealed that trihalomethanes (THMs) concentrations in all samples were below regulatory levels (100 μg/L). Although the national standard for haloacetic acids (HAA5) has not yet been promulgated in Taiwan, samples from two water plants contained HAA5 concentrations exceeding the USEPA limit (MCL of HAA5 of Stage 1, 60 μg/L). THMs and HAA5 were found to be the major disinfection by‐products in all water treatment plants. It was noted that the concentration of HAA5 in most samples was higher than that of the trihalomathanes. However, the formation potential of THM (THMFP) was found to be higher than that of HAA (HAAFP). Good correlation also was found between THMFP (or THMFP) and HAA5 (or THMs). In evaluating the performance of the treatment processes, it was found that conventional water treatment processes followed by activated carbon were effective in removing disinfection by‐products (DBPs) from source water with pre‐ozonation. The treatment processes were at their optimum performance in removing contaminants when O₃/TOC₀ was held at 0.75.     

Assesment of disinfection by‐products removal by ozonation coupled with adsorption

This research work was performed to evaluate ozonation and granular activated carbon adsorption processes from the view‐point of controlling the formation of disinfection by products (DBPs). Both the humic acid and raw water were first preozonated and then adsorbed on the activated carbon to assess the potency for removal of total organic carbon (TOC) and DBPs. The disinfection by‐product including THMs and HAAs, in principle, can be successfully removed through a use of the ozonation and granular activated carbon (GAC) adsorption processes. However, in practice dealing with the raw water, it is necessary to introduce the pilot‐plant to obtain the design and operation guidelines for the water treatment plant through the ICA (Instrumentation Control and Automation) program in our future research work.