4-AAP两波段光度洁同时测定水中酚类和芳胺

在ＰＨ为５．５的ＨＣｌ－（ＣＨ２）５Ｎ．介质中,铁氰化钾和过二硫酸铵存在下,用４－氨基安替吡啉（４－ＡＡＰ）两波段光度法可同时测定污水中０．１—３０ｍｇ／Ｌ的酚类和０．００８—３．０ｍｇ／Ｌ的芳胺．水样不需要预镏和萃取操作,石油类及０．３ｍｇ／ｔ以下的硫化物不于扰测定,Ｃｕ２＋、Ｆｅ３十的干扰可用ＥＤＴＡ掩蔽消除．酚类和芳胺的水样加标回收率酚类为９８％－１０５％,芳胺为９５％－１０５研究了１０种酚和１３种芳胺的测定灵敏度．     

农药单甲脒盐酸盐在棉田生态系统中的残留及持久性研究

单甲脒盐酸盐属低残留非持久性农药。在棉叶中的半衰期为４．４－８．ｌｄ,在土壤中为１１．４—１２．３ｄ。分别以２５％单甲脒盐酸盐水剂的１０、５０、１００、５００、８００、１０００和１５００倍稀释液喷施７—８次,每次间隔约１５ｄ,在棉籽中检测出单甲脒最高残留为０．１７×１０－６。科学合理地施用单甲脒农药,不会对人体健康造成危害。     

FX-4氟橡胶的老化行为研究

目的 研究FX-4氟橡胶在不同工况条件下的老化行为,为工程实践中科学评估装备使用寿命提供依据。方法 基于某装备对FX-4氟橡胶材料的使用要求,设计5种模拟工作状态条件的老化试验,通过观测样品外观形貌、力学、化学结构、打压密封等性能变化,研究FX-4氟橡胶在不同温度、不同介质和不同应变作用下的老化行为。结果 经过9 000 h老化试验,FX-4氟橡胶的压缩永久变形表现出明显增加的趋势,且增长速率呈现出先增大、再放缓、随后再次增大的变化规律。分解温度由508℃提升为520℃左右,表面结晶度和内部结晶度由61.7%分别下降为37%和48%左右,表明老化损伤由样品表面逐渐向内部扩展。分子结构没有发生根本改变,打压密封功能良好。结论 经过9 000 h老化试验后,FX-4氟橡胶出现不同程度的性能老化,但仍具备良好的密封性能,可正常使用。     

3种药物对寡毛双眉虫Diophrys oligothrix(纤毛虫门,腹毛目)的急性毒杀作用

通过海洋纤毛虫寡毛双眉虫Diophrysoligothrix对水产养殖中常用药物高锰酸钾、福尔马林及鲁哥氏液的急性毒性实验 ,以几率单位法获得双眉虫对福尔马林及鲁哥氏液的 2h、12h的半致死浓度LC50 值 :对前者 ,LC50 ,2h值为 5 9.35× 10 -6,LC50 ,12h为 5 2 .5 4× 10 -6;对于后者 ,LC50 ,2h为 12 4.5 4× 10 -6,LC50 ,12h为 72 .98× 10 -6.在此基础上对3种药物的作用效果及杀灭浓度进行了比较 ,结果表明 ,寡毛双眉虫对福尔马林的耐受力明显小于鲁哥氏液 ,同时显示高锰酸钾是在养殖动物耐受阈内可迅速杀灭纤毛虫的理想药物 .图 4表 5参 11     

介质阻挡放电等离子体降解CF4

采用介质阻挡放电(DBD)等离子体技术降解强温室气体CF₄,考察了外加气体氧气(O₂)、空气、氩气 (Ar) 对DBD降解CF₄的影响. 结果表明:随着放电时间的延长,CF₄降解率升高. 3种外加气体条件下,CF₄的降解率依次为Ar>空气>O₂. 外施电压1 000 V,Ar条件下放电4 min,CF₄降解率可达98.2%,而O₂条件下CF₄降解率只有36.9%. 水汽对CF₄降解有一定抑制作用. 红外光谱检测结果表明,降解产物主要为CO₂,CO和COF₂.      

硫酸亚铈催化下二苯甲烷的合成

介绍苯和苯甲醇在环境友好型催化剂硫酸亚铈的催化下合成二苯甲烷,研究了催化剂用量、反应时间对该傅克反应的影响.实验结果表明,该催化剂具有良好的催化活性,实验过程简单,无腐蚀,无废水污染.表1,参4.     

Interaction between cadmium,lead and potassium fertilizer (K<Subscript>2</Subscript>SO<Subscript>4</Subscript>) in a soil-plant system

A pot experiment was conducted to examine the influence of potassium (K) fertilizer (K₂SO₄) application on the phytoavailability and speciation distribution of cadmium (Cd) and lead (Pb) in soil. Spring wheat (Triticum aestivum L.) was selected as the test plant. There were seven treatments including single and combined contamination of Cd and Pb. CdCl₂·2.5 H₂O and Pb(NO₃)₂ were added to the soil at the following dosages: Cd + Pb = 0.00 + 0.00, 5.00 + 0.00, 25.0 + 0.00, 0.00 + 500, 0.00 + 1000, 5.00 + 500 and 25.0 + 1000 mg kg⁻¹, denoted by CK, T1, T2, T3, T4, T5 and T6, respectively. The K fertilizer had five levels: 0.00, 50.0, 100, 200 and 400 mg K₂O kg⁻¹ soil, denoted by K0, K1, K2, K3 and K4, respectively. The results showed that the K fertilizer promoted the dry weight (DW) of wheat in all treatments and alleviated the contamination by Cd and Pb. The application of K₂SO₄ reduced the uptake of Cd in different parts including roots, haulms and grains of wheat; the optimum dosage was the K2 level. K supply resulted in a significant (P < 0.05) decrease in the soluble plus exchangeable (SE) fraction of Cd and there was a negative correlation (not significant, P > 0.05) between the levels of K and the SE fraction of Cd in soil. The application of the K fertilizer could obviously restrain the uptake of Pb by wheat and there were significant (P < 0.05) negative correlations between the concentrations of Pb in grains and the levels of K in soil. K supply resulted in a decrease in the SE fraction of Pb (except the K1 level) from the K0 to K4 levels. At the same time, the application of the K fertilizer induced a significant (P < 0.05) decrease in the weakly specifically adsorbed (WSA) fraction of Pb and a significant (P < 0.05) increase in the bound to Fe–Mn oxides (OX) fraction of Pb. At different K levels, the concentration of Pb in the roots, haulms and grains had a positive correlation with the SE (not significant, P > 0.05) and WSA (significant, P < 0.05) fractions of Pb in the soil. All the K application levels in this experiment reduced the phytoavailability of Cd and Pb. Thus, it is feasible to apply K fertilizer (K₂SO₄) to alleviate contamination by Cd and/or Pb in soil. Moreover, the level of K application should be considered to obtain an optimal effect with the minimum dosage.     

Na_3PO_4-粉煤灰胶结材组合工艺处理垃圾焚烧飞灰

垃圾焚烧飞灰由于重金属含量高,被认为是危险废物,必须要加以稳定化处理。Na3PO4-粉煤灰组合工艺被用来稳定-固化焚烧飞灰中的重金属。结果表明,Na3PO4稳定-粉煤灰胶结材固化组合处理飞灰降低重金属浸出浓度明显,1.5%Na3PO4,25%掺量的粉煤灰胶结材固化飞灰后,养护7 d即可满足填埋标准。     

四氯乙烯和对二氯苯对草鱼的联合毒性

采用水生污染暴露试验和水生毒理联合效应相加指数法,研究了四氯乙烯(PCE)和对二氯苯(P-DCB)对草鱼(Ctenopharyngodon idellus)的单一毒性与联合毒性.结果表明,PCE和P-DCB的单一毒性均为高毒,且P-DCB的毒性大于PCE.PCE和P-DCB对草鱼的联合染毒在浓度1:1时,暴露时间为24,48,72,96h的相加指数(AI)分别为0.26,0.37,0.78,0.98,联合毒性为相加作用.PCE与P-DCB对草鱼的联合染毒在毒性1:1时,暴露时间为24,48,72,96h的AI分别为-0.15,0.24,0.83,1.30,联合毒性主要是相加作用,但是随着染毒时间的延长,联合毒性由相加作用向协同作用转变.     

零价铁协同超声波降解2,3,4,6-四氯酚的特性

研究了2,3,4,6-四氯酚(TeCP)在超声波/零价铁协同体系中的降解,结果表明,拟一级动力学能很好的拟合降解过程,协同体系中TeCP一级降解速率常数为0.0141min~(-1),为同等条件下零价铁体系降解速率常数的10.07倍,且大于两者之和,说明两者之间存在明显协同效应;零价铁(Fe~0)投加量、初始pH值、初始TeCP浓度(C_0)、超声功率和溶液离子强度等控制参数对TeCP降解速率的影响表明,其拟一级速率常数在Fe~0量为2g·l~(-1),初始pH值为6.0,离子强度0.8mol·l~(-1)Na_2SO_4以及超声功率350W时达最大值,并随着C_0的升高而降低.