电子束辐照分解甲苯的初步实验研究

进行了电子束辐照分解甲苯的静态实验研究,实验结果表明,电子束辐照能够有效地分解甲苯,在850keV、11kGy电子束的辐照下,初始质量浓度为1 000~3 000m g/m3的甲苯去除率可以达到77%以上,且甲苯去除率随吸收剂量的增加而提高。甲苯辐照分解的主要产物是苯甲醛和甲酸,此外还有少量苯、苯酚等。进一步验证了.OH在甲苯分解中的重要作用。     

宁夏盐池牧业生产系统的研究

本文采用系统科学的理论方法,详细地分析了盐池县牧业生产系统的内外关系与存在问题及相应的战略对策;结合对现实农业生态系统的能流与物流的定性分析,指出合理运行牧业生产系统,是使盐池县草原恢复、生态维持及农村经济发展的重要途径。     

微囊藻毒素降解菌S3的分子鉴定及其降解毒素的研究

对一株具有强降解微囊藻毒紊MC-LR能力的细菌S3进行了分子鉴定.测得该菌16S rDNA为1396bp,GenBank序列登录号为DQ836314.序列比对结果显示,该菌与类芽孢杆菌Paenibacillus validus的相似性达98%.微囊藻毒素降解实验结果表明,该菌能在以微囊藻毒素为唯一碳、氮源的培养基中生长,微囊藻毒紊在72h内减少78.3%,菌株S3的最适生长温度是30℃,最适生长pH值为7.0.     

Chemical and olfactive impacts of organic matters on odor emission patterns from the simulated construction and demolition waste landfills

The explosive increase of construction and demolition waste (CDW) caused the insufficient source separation and emergency disposal at domestic waste landfills in many developing countries. Some organic fractions were introduced to the CDW landfill process and resulted in serious odor pollution. To comprehensively explore the impacts of organic matters on odor emission patterns, five CDW landfills (OIL), with organic matters/ inert CDW components (O/I) from 5% to 30%, and the control group only with inert components (IL) or organics (OL) were simulated at the laboratory. The chemical and olfactive characters of odors were evaluated using the emission rate of 94 odorants content (ER_total), theory odor concentration (TOC_total), and e-nose concentration (ER_ENC), and their correlations with waste properties were also analyzed. It was found that the main contributors to ER_total (IL: 93.0% NH₃; OIL: 41.6% sulfides, 31.0% NH₃, 25.9% oxygenated compounds) and TOC total (IL: 64.1% CH₃SH, 28.2% NH₃; OIL: 71.7% CH₃SH, 24.8% H₂S) changed significantly. With the rise of O/I, ER_total, TOC_total, and ER_ENC increased by 10.9, 20.6, and 2.1 times, respectively. And the organics content in CDW should be less than 10% (i.e., DOC<101.3 mg/L). The good regressions between waste properties (DOC, DN, pH) and ${\mathrm{ER}}_{\stackrel{?}{\mathrm{ENC}}}$ (r=0.86, 0.86, -0.88, p<0.05), ${\mathrm{TOC}}_{\stackrel{?}{\mathrm{total}}}$ (r=0.82, 0.79, -0.82, p<0.05) implied that the carbon sources and acidic substances relating to organics degradation might result in that increase. Besides, the correlation analysis results (${\mathrm{ER}}_{\stackrel{?}{\mathrm{ENC}}}$ vs. ${\mathrm{TOC}}_{\stackrel{?}{\mathrm{total}}}$, r=0.96, p<0.01; vs. ${\mathrm{ER}}_{\stackrel{?}{\mathrm{total}}}$, r=0.86, p<0.05) indicated that e-nose perhaps was a reliable odor continuous monitoring tool for CDW landfills.     

焦作市工业燃煤量与大气SO_2污染关系模型研究

研究了焦作市工业燃煤量与大气SO2 污染的关系 ,建立了适合于焦作市城区大气SO2 污染的解析模型。在模型中尝试性地将面源污染产生的浓度贡献转化到背景值中计算 ,简化了解析模型。利用该模式计算了 1 996～ 2 0 0 0年焦作市城区大气中的SO2 浓度 ,并与监测数据进行对比分析 ,结果表明该模型适合研究区的实际情况 ,基于该模型实现了焦作市城区大气SO2 浓度的动态预测。     

转炉除尘循环水系统结垢与腐蚀浅析

本文通过分析典型转炉除尘系统水质变化规律,调查污垢、悬浮物成份及特点,研究了系统产生腐蚀和结垢的原因,并从技术和管理上提出了解决此问题的有效方法.     

The growth and Cu and Zn uptake of pakchois (Brassica chinesis L.) in an acidic soil as affected by chicken or pig manure

In a pot experiment, pig manure (PM) and chicken manure (CM) were applied to an acidic soil at application rates of 2%, 4% and 8% (W/W) to evaluate their effects on the growth, Cu and Zn uptake and transfer of five cultivars of pakchoi (Brassica chinesis L.). The results showed that alkaline manures significantly increased the biomass of pakchois, and also pH and electrical conductivity of the soil. Both 0.01 M CaCl2 and 1.0 M NH4NO3 salt solutions predict the Zn transfer from soil to pakchois well, but not for Cu. For the cultivar Siyueman, the transfer factors of Cu (or Zn) in the PM treatments were higher than that in the CM treatments. In our experiment the Cu and Zn concentrations in pakchois did not exceed the Chinese Food Hygiene Standard, but more attention should be paid to heavy metals risk on pakchois at lower soil pH and salt impairment by manures application.     

传统的超越与反思：可持续发展普世伦理的构建

本文认为可持续发展本涉及的是普世伦理问题,可持续发展目标的实现有赖于普适伦理规范的建立。在此基础上,本文初步分析了普世伦理的前提和原则,较详细地探讨了人与自然的伦理关系。     

膜生物反应器中污泥膨胀和腐败研究

针对聚醚砜膜生物反应器处理豆制品废水时发生的丝状菌污泥膨胀和污泥腐败问题,进行了实验研究。试验结果表明:污泥膨胀是由pH过低和有机负荷过高引起的,通过投加无水Na2CO3调节碱度和降低有机负荷,污泥沉降性能很快得到了改善;污泥腐败则是因废水厌氧降解过程所释放的NH3,CO2,H2S等气体所致。     

DNA甲基化结合蛋白

DNA甲基化是哺乳动物细胞中最重要的表观遗传学修饰之一,大约70%—80%的CpG发生这种甲基化修饰.异常的甲基化在许多癌症中频发,启动子CpG岛的高甲基化作为普遍的失活机制介导抑癌基因沉默.甲基化信号由甲基化结合蛋白来转译,它们能够特异性识别并结合至甲基化位点通过募集辅阻遏复合物例如组蛋白去乙酰化酶(Histone Deacetylase,HDAC)等建立沉默的染色质,从而在DNA甲基化和基因沉默中起桥梁作用.目前,哺乳动物中已鉴定出的甲基化结合蛋白有三类,分别是:MBD(Methyl-CpG-Binding Domain)、Kaiso以及SRA(Set and Ring finger-associated)家族.本文就这三大家族(以MBD为主)各自的结构、功能、结合甲基化DNA的特性以及它们在某些疾病发生中的作用做一综述.