我国微生物农药的应用现状

对微生物农药的概念、种类及其作用机理进行了综述,其中重点介绍了微生物农药的分类,同时对我国目前使用的几类微生物农药的研究应用状况进行了阐述,并提出微生物农药现存的问题及其解决方案,指出微生物农药的发展前景是乐观的。     

Organochlorine insecticide residues in drinking and ground water in and around Delhi

A multiresidue method was developed for the estimation of 15organochlorine pesticides in water. 50 samples of drinking watersupplied by the Municipal Corporation to the residential areasof Delhi and 20 ground water samples from nearby villages usedfor irrigation were monitored for the presence of organochlorineinsecticides by the method developed. Although, organochlorinepesticides were detected in the ground water and irrigationwater samples, the levels of pesticides were below the MaximumContaminant Level as prescribed by WHO. No organochlorineinsecticides were detected in any of the drinking water samples.     

Trends in Pesticide Use and Efficacy During 26 Years of Changing Agriculture in Southern England

We report on trends in agricultural pesticide use from1970 to 1995 inclusive in arable crops on the SouthDowns, West Sussex, U.K. Information is given on theproportion of cropped area treated with pesticides,the percentage spray area, the number of pesticideapplications per field, and the number of compoundsapplied per field for herbicides, foliar fungicidesand insecticides. Compared to national publishedfigures, our data are broadly representative of thenational picture; they provide a complete and detailedtime series whereas national figures are available foronly 7 out of the 26 yr. In general, the areatreated (fungicides, insecticides) and the intensityof use (all three types of pesticide) increased overthe 26 yr. The spectrum of activity of theherbicides applied to arable crops increased from anaverage of 22 weed taxa susceptible in 1970 to 38 weedtaxa susceptible in 1995. The odds on herbicide andfungicide use in break crops were, respectively, 93%and 99% lower than average; odds on insecticide usein spring cereals were 98% lower than average. Comparing winter wheat on the most traditional farm(grass/cereal rotation) with the most modern one(monoculture winter wheat), the proportion of fieldstreated with herbicides was similar, but the odds onbeing treated with fungicides were 129% higher on themodern farm. Insecticides were used in only 2% ofthe fields on the traditional farm, while on themodern farm over the same time period, 79% of thefields were treated. This fits previously observeddifferences in wildlife abundance on the two farms.     

Monitoring of Organochlorine Pesticide Residues in Summer and Winter Vegetables from Agra, India – A case study

Analysis of summer and winter vegetable samples during 2002–2003 for pesticidal contamination was carried out on Gas Chromatograph-Electron Capture Detector with capillary columns. The contamination levels of winter vegetables (average concentration of 4.57, 6.80 and 5.47 ppb respectively for Lindane, Endosulphan and DDT) were found to be slightly higher than the summer vegetables (average concentration of 4.47, 3.14 and 2.82 ppb respectively for Lindane, Endosulphan and DDT). The concentration of these organochlorine pesticides in summer and winter vegetables were well below the established tolerances but continuous consumption of such vegetables even with moderate contamination level can accumulate in the receptor's body and may lead to chronic effects that could be fatal.     

气相色谱法测定土壤和沉积物中12种有机磷农药

建立了索氏提取-固相萃取（SPE）小柱净化-GC-NPD测定土壤和沉积物中的12种有机磷农药的方法。用正己烷-丙酮（9：1）进行索氏提取,SPE硅胶小柱净化,15 mL乙酸乙酯洗脱。适用于土壤和沉积物的干样和湿样中12种有机磷农药的测定,取样量为10 g时,方法检出限为0.304~1.469 μg/kg,样品加标平均回收率为67.10%~109.8%,相对标准偏差为3.39%~14.7%。     

Facile and Sensitive Spectrophotometric Determination of Synthetic Pyrithroids in Their Formulations, Water and Grain Samples

A novel reagent was introduced for the facile and sensitive spectrophotometric determination of syntheitic pyrethroids in their formulations (fenvalerate, cypermethrin and decamethrin), water and grain samples. These methods were based on the hydrolysis of synthetic pyrethroids under the alkaline conditions to form respective aldehyde groups. These groups were condensation with 3-methyl-2-benzothiazolinone hydrochloride (MBTH) to yield color derivatives having λ_max at 520 nm for fenvalerate, 516 nm for cypermethrin and 512 nm for decamethrin. The proposed method could be successfully applied for the determination of synthetic pyrethroids in their formulations, water and grain samples.     

Monitoring of Seasonal Vegetables for Pesticide Residues

Market samples (60) of six seasonal vegetables were monitoredduring 1996–1997 to determine the magnitude of pesticidalcontamination. The estimation of insecticide residuesrepresenting four major chemical groups i.e. organochlorine,organophosphorous, synthetic pyrethroid and carbamate, was doneby adopting a multiresidue analytical technique employingGC-ECD and GC-NPD systems with capillary columns. The testedsamples showed 100% contamination with low but measurableamounts of residues. Among the four chemical groups, theorganophosphates were dominant followed by organochlorines,synthetic pyrethroids and carbamates. About 23% of the samplesshowed contamination with organophosphorous compounds abovetheir respective MRL values. More extensive studies coveringdifferent regions of Haryana state are suggested to get a clearidea of the magnitude of vegetable contamination with pesticideresidues.     

Extractive Spectrofluorometric Determination of Quinalphos Using Fluorescein in Environmental Samples

A simple, sensitive, convenient and low cost spectrofluorometric technique for determination of quinalphos is described. Quinalphos is decomposed with sodium ethoxide. Resultant sodium diethyl thiophosphate (Na-DETP) is extracted with a cationic fluorescein as ion pair complex into 1-chloro-2-nitrobenzene. The fluorescence of the ion pair, fluorescein-DETP is measured at 530 nm after excitation at 490 nm. This technique is applicable for the determination of quinalphos in water, food grains and vegetable samples up to ng level with Amberlite XAD-4.     

差分光谱法连续监测空气中SO2、NO2、苯、甲苯方法探讨

差分光谱法(简称DOAS)已广泛用于空气中SO2、NO2、苯、甲苯监测.通过对差分光谱法监测结果与其他传统仪器进行时比,发现用DOAS监测SO2、NO2与点式仪器有较好的一致性,但用DOAS系统监测苯、甲苯与气相色谱法有机物连续监测结果差异较大,相关性较差,运行有一定的局限性.另外,本文对DOAS的最佳运行条件进行了探讨,发现影响光强的氙灯老化和气候条件对DOAS系统运行有较大影响.     

基于网格空间数据的晋陕蒙接壤区生态环境综合评价

晋陕蒙接壤区是典型的生态过渡带、生态脆弱带。文章在调查研究的基础上 ,选取了 1 3个评价指标 ,应用层次分析法确定其权重 ,并将各个因子分级标准化和定量赋值 ,再用加权求和法得到每个评价单元的环境质量综合评价指数。根据环境综合评价指数将环境质量分为较好 (≥ 8)、一般 (≥ 6～ <8)、较差 (≥ 4～ <6)、恶劣 (<4) 4级。结果表明 :晋陕蒙接壤区的环境质量大多处于较差等级 ,较好、一般、较差、恶劣等级的面积比例分别为 2 .2 % ,2 8% ,5 7.4%和1 2 .4%     

Combined Non-Catalytic Reduction of NOx and SO2 by Ammonia Liquor during Staged Fluidized-Bed Combustion

Emissions of NOx and SO2 were monitored in the presence of ammonia liquor in a 0.09 m2 and 2 m high stainless-steel fluidized-bed combustor. Experiments were carried out at 2 m/s fluidizing velocity, 40% excess air, and 870 °C bed temperature. Ammonia liquor with 7% ammonia by weight was injected into the freeboard of the combustor 52 cm above the distributor through a water-cooled injector. A 65 : 34 primary/secondary air ratio was maintained throughout the investigation. Approximately 70% of NO and 20% of SO2 was reduced at an NH3/NO molar ratio of 2 : 1, respectively. However, a higher reduction in SO2 emissions (62%) was achieved at a very high NH3/NO molar ratio of 7 : 1. These experiments showed that ammonia addition did have a significant effect in SO2 reduction if injected in an excess amount. The injection of ammonia liquor combined with staged combustion was found to be very effective in reducing NOx emissions. A reduction of about 50% was achieved at an NH3/NO molar ratio of 0.6 : 1 which is also coupled with a very low level of ammonia in the flue.     

IC色谱仪电位法测定S^2—的运用与研究

介绍了应用ＹＩＣ－８型离子色谱仪电化学检测器测定标准样品及废水样中Ｓ＾２－的含量,同时与化学法进行比较,肯定了电位法的准确性、可靠性。     

惠州市城区NO2污染水平的分析与模拟

分析了2004年惠州市城区各监测站点的NO2数据,结果表明,NO2对城区空气质量影响不大。采用了城市空气质量管理软件模拟了NO2空间分布及日变化情况,且与实测值的比较分析表明,模拟结果在城区内有可比性。但地处城市边缘地带的污染模拟受光化学和区域性污染的影响,有待于进一步研究。所得结论可为惠州市城区优化布点的研究提供一定的参考。     

Development of simple and sensitive spectrophotometric method for the determination of bendiocarb in its formulations and environmental samples

Facile, selective and sensitive spectrophotometric method has been developed for the determination of bendiocarb in its insecticidal formulations, fortified water, food grains, agriculture wastewater and agriculture soil samples with prepared reagents. The method was based on alkaline hydrolysis of the bendiocarb pesticide, and the resultant hydrolysis product of bendiocarb was coupled with 2,6-dibromo-4-methylaniline to give a yellow color product with λmaxof457 nmorcouplingwith2, 6−dibromo−4−nitroanilinetoproducearedcoloredproductwithλ_max of474~nmorcouplingwith2, 4, 6−tribromoanilinetoformorangeredcoloredproducthasaλ_max of465 nm.Underoptimalconditions, Beer'slawrangefor2, 6−dibromo−4−methylaniline(DBMA)wasfoundtobe0.6−−14.0~μgmL ^-1, 0.8−−10.0 μgmL ^-1 for2, 6−dibromo−4−nitroaniline(DBNA)and0.4−−10.0 μgmL ^-1 for2, 4, 6−tribromoaniline(TBA).Themolarabsorptivityofthecolorsystemswerefoundtobe4.126~×~10⁴ lmol ^-1 cm ^-1 forDBMA, 3.254×10⁴ l~mol ^-1 cm ^-1 forDBNAand2.812×10⁴ lmol ^-1 cm ^-1 forTBA.Sandell'softhecolorreactionsare0.018 μgcm ^-2(DBMA), 0.052 μgcm ^-2(DBNA)and0.065 μgcm ^-2$ (TBA) respectively. The effect of the non-target species on the determination of bendiocarb was studied. The formation of colored derivatives with the coupling agents is instantaneous and stable for 18 h, 30 h, and 12 h. Performance of the proposed methods were compared statistically in terms Student's F and t-tests with the reported methods.     

示波极谱滴定法测定水和废水中的溶解氧

在pH值为6.5的NaAc-HAc底液中,加入经处理后的水样10ml,用EDTA标准溶液滴定其中的Mn^2 ,以EDTA在示波极谱上的切口到一定深度指示终点,废水的色度、浊度等对测定不产生干扰,不需进行预处理,操作简便、快速。该方法的相对误差小于1.0%,变异系数小于0.7%。     

Spatio-Temporal Variations of Sulphur Dioxide Patterns with Wind Conditions in Central Taiwan

Sulphur dioxide (SO₂) is one of the main atmospheric pollutants in central Taiwan. This article analyses the SO₂ concentration seasonal variations and spatial distribution using data obtained from ten air quality monitoring stations and the Taiwan Weather Bureau. It reveals that SO₂ concentration is high in winter and low in summer and that high concentration centers are located south of the Taichung coal-fired power plant, the main source of SO₂ emissions in the region.The location of high concentration centers changeswith different prevailing winds. SO₂ variations due towind direction are not unique. During short periods,when meteorological conditions are constant, variationin the pollution sources cause variations in thespatial distribution. This has been deduced byappreciation of Intervention analysis to time seriesof hourly data.     

石家庄市NO2时空分布特征及影响因素

为了解石家庄市NO₂时空分布特征及影响因素,结合GIS和相关性分析,对2018年环境空气自动监测站监测数据、气象数据和社会经济数据进行统计分析。结果表明：261个乡镇NO₂年均质量浓度范围为11～68μg/m³,超标率为47.9%,仅有49个乡镇NO₂日均质量浓度达到国家二级标准。主城区NO₂质量浓度高于周边县(市、区),NO₂总体呈圆环形带状分布。月变化方面,1—3月、10—12月污染较重,峰值出现在1月。NO₂日变化呈“高-低-高”的变化趋势,区域差异明显。NO₂与温度、湿度、风速呈负相关,与大气压呈正相关,气象条件的月际差异是导致NO₂月差异的重要因素,NO₂空间分布主要受地形、人口密度和机动车排放等因素影响。研究结果提示秋冬季是NO₂治理的关键时期,主城区为重点防控治理区域。     

南通市区静态管理期间空气质量分析

对南通市区2022年4月初因疫情防控采取全区域静态管理期间的空气质量进行分析,以气象参数、臭氧前体物VOCs和NO_x作为分析对象。结果表明:此次污染过程的主导因素是高温、强辐射、低湿和偏南风的气象条件。南通市区处于VOCs控制区,高温、强辐射使得VOCs挥发性增强,浓度升高。偏南方向的苏通园区和能达公园VOCs浓度较高且升幅较大,源解析结果表明这2个点位涂料溶剂使用占比升幅更高,既容易受附近石化和储油库影响,也容易受偏南风向的污染输送影响。据初步统计,静态管理期间南通市区停工数量为80%左右,污染期间NO₂浓度高值区主要分布在沿江一带,长江南岸的张家港和常熟地区存在多家高排放企业,在偏南风下,张家港和常熟的污染物极易输送至南通市区。基于空气质量模型WRF-CAMx的O₃和PM_2.5来源解析结果显示,静态管理期间外来输送明显,占比为68.7%~84.7%。污染期间的船舶排放和二次转化贡献也不容忽视。建议南通市应重点加强工业、油气挥发和涂料溶剂源减排,同时加强区域联防联控,以便进一步改善空气质量。     

A2/O工艺脱氮除磷运行效果分析

采用统计学方法对新疆某污水处理厂A2/O工艺进行进水水质数据分析,发现数据存在严重自相关现象,运用主成分消除法和岭回归消除法以消除自相关性。结果表明：TN和TP是污水厂提标改造的关键;碳源匮乏和缺氧区存在溶解氧(DO)是TN去除不佳的主要原因;适当提高污泥浓度(MLSS)和水力停留时间(HRT)是强化TP去除的措施;温度是影响脱氮除磷的主要因素。将温度模型与自相关磷模型相结合,可提高磷模型精度,有利于出水TP的预测。降低DO、增加外碳源,控制MLSS为3 500 mg/L~4 500 mg/L、HRT为5.4 h~8.0 h、厌氧区和好氧区DO为0.3 mg/L和2 mg/L、污泥龄（SRT）为11 d~12 d,可提升工艺脱氮除磷效果。     

基于GOSAT卫星的中国CO2浓度时空特征分析

采用温室气体观测卫星(GOSAT) 傅里叶变换光谱仪(FTS)发布的CO₂柱浓度L₃级别数据集产品,利用TCCON地基站点的CO₂柱浓度数据对卫星遥感数据进行验证,分析中国CO₂柱浓度时空变化特征及其影响因素。研究结果表明,GOSAT卫星的CO₂柱浓度产品精度较高,线性回归的r²为0.99,线性方程斜率为0.98,平均偏差为0.11 mg/L。中国CO₂柱浓度呈现逐年增长的趋势,存在12个月的周期性季节性变化。2010、2020年区域年平均CO₂柱浓度分别约为389.30、412.62 mg/L,增长了23.32 mg/L,年平均增长率大约为0.58%。中国区域大气CO₂柱浓度的月变化存在明显的时空差异,最大值和最小值分别出现在4月和8月,2020年4月和8月的区域平均值分别为415.09、409.13 mg/L。中国区域CO₂柱浓度从东部沿海向西部逐级递减,且呈现明显的季节性变化,夏季高值主要集中在东南部沿海地区,冬季高值主要集中在华北地区。