Reversed association between levels of prostate specific antigen and levels of blood cadmium and urinary cadmium

Prostate cancer associated with cadmium exposure may indicate a link between prostate specific antigen (PSA) and levels of blood cadmium (BCd) and urinary cadmium (UCd). Thus, these associations were investigated. We recruited 295 men, 50 years of age and above from a health check-up program at a health center as subjects of the study. They completed a self-reported questionnaire and provided fasting samples of blood and urine for cadmium assay. The assay was performed using atomic absorption spectrophotometry. Blood samples were also collected for the assays of total cholesterol and high-density lipoprotein measures. The means of BCd and UCd increased with age and the means of all subjects were 1.19 ± 1.04 μg L⁻¹ and 1.37 ± 1.76 μg g⁻¹ creatinine, respectively. The PSA levels were positively associated with the lipid levels, but reversely associated with BCd and UCd levels. The multivariate logistic regression analysis showed that men with PSA ? 4.0 ng mL⁻¹ had an odds ratio (OR) of 0.4 (95% CI = 0.1-0.9) to have BCd > 0.49 μg L⁻¹, and an OR of 0.4 (95% CI = 0.2-1.0) to have UCd > 0.45 μg g⁻¹ creatinine. In conclusion, the PSA levels are reversely associated with BCd and UCd levels.     

Sequestration of organochlorine pesticides in soils of distinct organic carbon content

In the present study, five soil samples with organic carbon contents ranging from 0.23% to 7.1% and aged with technical dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) for 15 months were incubated in a sealed chamber to investigate the dynamic changes of the OCP residues. The residues in the soils decreased over the incubation period and finally reached a plateau. Regression analysis showed that degradable fractions of OCPs were negatively correlated with soil organic carbon (SOC) except for α-HCH, while no correlation was found between degradation rate and SOC, which demonstrated that SOC content determines the OCP sequestration fraction in soil. Analysis of the ratio of DDT and its primary metabolites showed that, since it depends on differential sequestration among them, magnitude of (p,p′-DDE + p,p′-DDD)/p,p′-DDT is not a reliable criterion for the identification of new DDT sources.     

ZnO/LixNi1-xO光催化降解甲基橙的研究

采用溶胶凝胶法制备LixNi1-xO和ZnO粉体,利用球磨法制备ZnO/LixNi1-xO复合粉体,以紫外光为光源,通过降解甲基橙,研究了锂掺杂及n-p复合对氧化镍的光催化性能影响。结果表明：当投放量为0.1 g/L,x≤0.075（摩尔分数）的锂掺杂氧化镍均比未掺杂氧化镍的光催化活性高。当锂掺杂摩尔分数为0.025,投放量为0.4 g/L时锂掺杂氧化镍的光催化活性最佳,甲基橙最高降解率达到93.1%。当ZnO/Li0.025Ni0.975O在质量比为1∶1,投放量为0.2 g/L时光催化活性最佳,甲基橙最高降解率达到98.1%。     

竹炭对废水中Cu2+的吸附

探讨了竹炭粒径、加入量、溶液 pH、吸附时间、Cu2+初始质量浓度等因素对竹炭吸附 Cu2+效果的影响.实验结果表明:竹炭对废水中Cu2+有很好的吸附效果,当竹炭粒径小于0.15 mm、加入量为 16 g/L、溶液 pH 为 6.0、Cu2+初始质量浓度 25 mg/L、吸附时间为 1.5 h 时,竹炭对 Cu2+的去...     

废水反硝化除磷技术研究进展

结合近年来国内外最新研究成果,综述了反硝化除磷机理及工艺.重点介绍了反硝化聚磷菌的微生物学特性和除磷特性,以及不同种类的反硝化除磷工艺,并对反硝化除磷技术进行了展望.     

燃煤电站SCR烟气脱硝工程技术关键问题研究

对SCR烟气脱硝催化剂的选择、脱硝系统旁路设置与脱硝装置流场模拟这三个当前我国燃煤电站SCR烟气脱硝工程技术中的关键问题进行了分析与探讨,并提出了解决措施,为提高脱硝工程技术水平、完善当前SCR烟气脱硝技术规范提供借鉴。     

化工建设项目环境影响评价中几个问题的探讨

从炼油厂煤制氢装置碳资源的利用、炼化装置所产生废物的焚烧处理、炼油装置加氢工艺技术的综合能耗、清洁生产标准的运用、废水处理及废水回用技术等方面对化工建设项目的环境影响评价中存在的问题进行了探讨,以促进我国化工建设项目环境影响评价工作的规范化和法制化.     

Effects of Preparation Parameters on Properties of Soy Protein-Based Fiberboard

The effects of manufacturing parameters on mechanical properties of medium density fibreboard (MDF) bonded with modified soy protein-based glue were studied to find an appropriate manufacture technology. Physical properties of MDF made with different amount of wax emulsion were measured. Results indicated that water repellent had no obvious influence on physical properties of soy protein-based MDF boards. The fiberboards bonded with soy protein-based glue showed stronger water resistance properties than those bonded with urea–formaldehyde (UF) resins. Furthermore, the soy protein-based MDF boards had good quality [25.2% 24 h soak thickness swell (TS), 29.9 MPa modulus of rupture (MOR), 3130 MPa modulus of elasticity (MOE)], which met requirements of Chinese national standard. Practical processing parameters were obtained by orthogonal experiment, i.e., glue content 8.0%, hot-press temperature 200 °C, and hot-press time 150 s.     

分子筛吸附法脱除废水中的聚丙烯酰胺

聚丙烯酰胺(PAM)用于油田驱油产生大量难处理的含聚废水。以分子筛为吸附剂处理含聚废水,研究分子筛类型(Y、Beta和ZSM-5,H型和Na型)和物化性质对其吸附PAM性能的影响,并测定吸附等温线。结果表明,吸附性能顺序为BetaYZSM-5,H型优于Na型。H-Beta对PAM的吸附来自分子筛中阳离子与PAM中阴离子的静电作用,Si—O和Al—OH与PAM中酰胺基的氢键作用。H-Beta开放的通道结构,较高的介孔比例和表面积,较强的酸性和良好的酸中心可接近性使其具有优异的吸附性能。Si O2/Al2O3=26的H-Beta对浓度为200 mg/L的PAM溶液,PAM脱除率可达95.2%。在低PAM平衡浓度时,PAM在H-Beta上的吸附符合Langmuir单层吸附特征,饱和吸附量达70.2 mg/g,在高浓度区域则由于PAM疏水缔合作用加强呈现多层吸附。     

光照条件对跑道池光生物反应器内蛋白核小球藻生长特性的影响

本文采用多孔曝气管的曝气方式,以蠕动泵为藻液循环的动力,研究了气体流量、光照强度、光照周期等因素对跑道池光生物反应器内蛋白核小球藻生长与代谢特性的影响,并利用傅里叶红外光谱半定量法对不同光照条件下藻细胞内蛋白质、油脂以及多糖含量变化进行了分析。研究结果表明,适当的气体流量、光照强度和光照周期有利于跑道池内蛋白核小球藻细胞的生长和代谢。在本实验条件下,在最佳气体流量2 000 m L/min条件下,光照强度为3 500μW/cm2,光照周期为16∶8时最有利于蛋白核小球藻的生长;光照强度为2 000μW/cm2和光照周期为16∶8的条件均有利于藻细胞内油脂的积累。