不同配方复合肥对胡椒生长效应的研究

1988—1990年在我国重要的胡椒产区——海南省万宁县,进行胡椒施用不同配方复合肥的田间试验。结果表明,N:P_2O_5:K_2O为12:6:13加微肥的配方是胡椒专用肥的较佳配方,施用效果柑当或优于N、P、K比为15:15:15的进口复合肥,比当地常规施肥增产20.2％,能节省肥料成本,有显著的经济效益,可在试区大面积推广。     

Characterization of distribution of pesticide residues in crop units

The characteristic features of distribution of pesticide residues in crop units and single sample increments were studied based on more than 19,000 residue concentrations measured in root vegetables, leafy vegetables, small-, medium- and large-size fruits representing 20 different crops and 46 pesticides. Log-normal, gamma and Weibull distributions were found to provide the best fit for the relative frequency distributions of individual residue data sets. The overall best fit was provided by lognormal distribution. The relative standard deviation of residues (CV) in various crops ranged from 15–170%. The 100–120 residue values being in one data set was too small to identify potential effects of various factors such as the chemical and physical properties of pesticides and the nature of crops. Therefore, the average of CV values, obtained from individual data sets, were calculated and considered to be the best estimate for the likely variability of unit crop residues for treated field (CV = 0.8) and market samples (CV = 1.1), respectively. The larger variation of residues in market samples was attributed to the potential mixing of lots and varying proportion of non-detects. The expectable average variability of residues in composited samples can be calculated from the typical values taking into account the sample size.     

臭氧氧化印染工业园废水的效能与机理研究

本研究开展了印染废水臭氧氧化影响因素、降解动力学和淬灭实验,测定了自由基物种、降解产物和琥珀酸脱氢酶活性.结果表明,苯胺去除效率随着pH值、臭氧投加量和臭氧投加速率的增加分别逐渐减小、增加和减小,且臭氧浓度为24 mg·L^-1时苯胺去除效率最高.臭氧氧化苯胺的适宜条件为：臭氧浓度为24 mg·L^-1、臭氧投加量为200 mg·L^-1和臭氧投加速率为4 mg·min^-1,此时苯胺的去除效率为47.2%.臭氧氧化苯胺是直接氧化为主结合羟基自由基反应的作用过程.苯胺脱氨基和裂解苯环后生成戊二酸或L-焦谷氨酸直至矿化.大肠杆菌在原水和臭氧氧化后废水中的酶抑制率分别为83.4%和24.7%.臭氧氧化前处理后,混凝去除色度、SS、COD、总氮、总磷、硫化物和苯胺的效能分别提高了0.72%、0.46%、31.40%、9.40%、22.80%、31.40%和63.30%.研究结果为臭氧氧化印染工业园废水前处理的应用提供了基础依据.     

混合物质谱的简单分类算法

有毒化合物质谱分类是以光谱数据的数值特性为基础的。这此数据的计算机分类提供了各种参数,用以确定属于有毒化合物中某一类的对应化合物。质谱数据的简单分类算法常被用于自相关变换质谱的主分量建模。主分量的有效值为相互确认为确定。对环境空气中１１９种被监测的有毒化合物,有色谱－质谱联用的试验和校正数据所得到的４类预报正确率为７６．５％。     

电动联合法对复合重金属污染底泥的修复

河流与湖泊底泥中重金属污染物的清除是实现水体彻底净化及底泥工程利用的关键。以增加了电解液循环的电动联合装置为修复设备,以Cu、Zn、Pb、Cr、Ni污染底泥为研究对象,结合小试模拟和中试模拟实验,明确修复装置对复合污染底泥的净化修复效果,并优化污染物回收的技术参数。结果表明,增设电解液循环有助于增强复合污染底泥中重金属离子的迁出,在小试模拟和中试模型实验中,底泥污染物的去除率分别达到了74%~84%和52%~60%;中试模型实验修复后底泥中的Cr、Cu、Ni和Zn含量分别为140.31、314.47、250.93、464.17 mg·kg⁻¹,低于《土壤环境质量-建设用地土壤污染风险管控标准》(GB 36600-2018) 的筛选值。在两极电解液增设pH调节装置和斜板沉淀池有助于以Cr(OH)₃、Cu(OH)₂、Ni(OH)₂和Zn(OH)₂沉淀物的方式对重金属离子进行回收,阳极电解液pH控制在5.0~6.5,阴极电解液pH控制在10时,阴阳极两侧电解液中重金属沉淀回收率均达99%。增加了电解液循环的电动联合修复技术可同步实现底泥污染物的净化及回收。     

二氧化钛涂覆材料对甲苯的光催化降解作用

在自制的模拟小室中对二氧化钛涂覆材料的光催化性能进行了初步研究，在玻璃、瓷砖和日光灯这3种常见材料表面涂覆了二氧化钛，并以甲苯为模型化合物，测试了3种材料的净化性能。结果表明，3者对甲苯均有一定的降解效果，是有实用前景的光催化净化材料。     

Measurement of residues of benomyl and mancozeb pesticides in shrub and nonshrub cucumbers sampled from different regions of Mazandaran province (Iran)

Farmers use mancozeb against cucumber pests, such as Perono spoxa, in large amounts without consideration of potential chronic human health hazards resulting from pesticide accumulation in food and fruits. Considering the necessity of food for humans and importance of fruit in daily diet, as well as the determination of pesticide residues in food and fruits as mandated by WHO and FAO, the residues benomyl and mancozeb, the most prominently used pesticides in Iran, were measured. In this study cucumbers from 76 sample regions were used. Data showed that the amounts of benomyl was related to the type of cucumber in the regions, but there was no significant relationship between the amount of mancozeb and type of cucumber.     

造纸漂白废水中有机氯化物处理技术

在调研国内外文献资料的基础上，对有关制浆造纸漂白废水污染控制技术研究现状从物化法，化学法，生化法等方面进行了综述，对系统开发研究高效，经济，节能的漂白废水处理工艺有重要的参考作用。     

Levels of Persistent Organochlorine Residues in Eggs of Greater Flamingos from the Guadalquivir Marshes (Doñana), Spain

Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) residue levels were determined in 53 unhatched eggs from greater roseus flamingos (Phoenicopterus ruber). Eggs were collected in 1996 from the National Park of Doñana (Guadalquivir marshes, Southwest Spain), immediately after one breeding colony abandoned the nesting site due to predator attacks. The main metabolite of p,p′-DDT, p,p′-DDE, was the OCP residue found at higher concentrations, with a geometric mean of 721 ng/g wet weight. Residues of other pesticides, including some hexachlorocyclohexane isomers, hexachlorobenzene, aldrin, heptachlor, and heptachlor-epoxide, were detected at much lower concentrations. The sum of PCBs was 528 ng/g, with PCB congeners #187 and #153 being the most prominent in eggs. The pattern observed in these compounds of industrial origin corresponded more to Aroclor 1260 than to any other commercial mixture. Levels of organochlorine residues indicate a medium degree of exposure, and they are not considered of any concern for the flamingo population. In particular, neither p,p′-DDE nor PCB levels were found to be correlated with the eggshell thickness.     

Application of an enzyme-linked immunosorbent assay for the detection of clenbuterol residues in swine urine and feeds

The present study outlines applications of an enzyme-linked immunosorbent assay (ELISA) for the analysis of clenbuterol residues. Antisera were raised from rabbits immunized with diazotized clenbuterol-bovine serum albumin (BSA) conjugate. The assay was specific to clenbuterol with a half-maximum inhibition concentration (IC₅₀) of 1.8 ng/mL and 2.5 ng/mL in blank swine urine and phosphate buffer solution, respectively. The assay had high cross-reactivity (86%) with mabuterol, but low with other adrenergic agonists and antagonists. The average recovery of clenbuterol, as measured with the ELISA, ranged from 90% to 112% in swine urine samples and from 86% to 95% in feeds, respectively. This new assay was compared with commercial ELISA test kits. An excellent correlation (r ² = 0.98) between the two methods and satisfactory recoveries suggest that the new assay can be suitable for the determination of clenbuterol residues in real samples. The assay was used to analyze clenbuterol residues in 103 swine urine samples and 68 feed samples collected from northern China. Approximately 50% of the urine samples and 25% of the feed samples analyzed were found positive (concentration of clenbuterol ≥ 1 ppb). The results indicate that clenbuterol was misused in some of the areas surveyed.