甲基异柳磷等四种农药在土壤薄板上的移动性能

在室内模拟条件下，研究了４种农药在土壤薄板上的移动性能。结果表明，甲基异柳磷与嘧啶氧磷属不易迁移的Ⅱ级农药；克草胺属中等迁移性的Ⅲ级农药；单甲脒属可移动性农药。     

甲基异柳磷等四种农药的水解特性研究

本文测定了甲基异柳磷、单甲脒、克草胺、嘧啶氧磷等四种农药在不同温度和不同pH条件下的水解速率、探讨了影响水解的主要因素。结果表明,在中性水溶液中,25℃时四种农药的水解半衰期分别为:甲基异柳磷270.8d,单甲脒6.5d,克草胺602.7d,嘧啶氧磷55.9d;当温度升至50℃时,四种农药的水解速率均有不同程度的增加,增幅为原来的2.0—10.8倍;改变pH亦会影响水解速率,甲基异柳磷和单甲脒均随pH增加水解大大加快;克草胺则在中性及碱性条件下很稳定,在酸性条件下稳定性较差;而嘧啶氧磷在酸碱条件下都不如在中性条件下稳定。     

甲基异柳磷等四种农药对土壤呼吸的影响

本文采用密闭法(直接吸收法)测定了甲基异柳磷等四种农药对土壤呼吸的影响,并对其进行了安全性评价。评价结果表明,甲基异柳磷等四种农药对土壤呼吸基本无影响,属低毒级农药。     

四种农药对蛙类的毒性与评价

测定了甲基异柳磷等四种新农药对泽蛙蝌蚪的毒性，作出了安全性预评价。结果表明：四种农药对蛙类均为无实际危害的低毒农药。克草胺施药期与蛙类蝌蚪期正相吻合，因此在使用时应采取措施，尽量避免对蛙类蝌蚪的毒害。     

气相色谱法测定糙米中水胺硫磷和甲基异柳磷的残留量

本文用带氮磷检测器的气相色谱仪,测定糙米中水胺硫磷和甲基异柳磷残留量,结果表明:水胺硫磷和甲基异柳磷最小检出量分别为1.3×10~(-11)g和2.8×10~(-12)g,最低检出浓度分别为0.7ppb和0.1ppb,回收率添加浓度为0.05—5mg/kg时,回收率范围分别为89.9—97.8％和100.7—104.9％,变异系数绝对值分别为3.42—5.58％和1.33—2.36％。     

磺胺嘧啶在水中的微生物降解研究

为了探明磺胺嘧啶在水中的环境行为,通过室内模拟降解实验分别研究了磺胺嘧啶在湖水和猪场废水中的好氧和厌氧微生物降解,考察了供氧方式和有机质含量对磺胺嘧啶微生物降解的影响。结果表明:磺胺嘧啶在猪场废水中厌氧微生物降解速率高于其好氧组,而磺胺嘧啶在湖水中厌氧微生物降解速率低于其好氧组。磺胺嘧啶在湖水和猪场废水中的好氧或厌氧微生物降解均较缓慢,这可能与其较强的抑菌性和微生物的营养状况有关。通过微生物培养还研究了好氧降解时磺胺嘧啶对湖水中微生物种群生长的影响,数据显示:磺胺嘧啶对湖水和猪场废水中细菌的生长具有一定的刺激作用,而对真菌和放线菌的生长影响不明显。     

Halomonas socia NY-011~T中四氢嘧啶合成基因簇ectABC和ectD的克隆及其功能鉴定

由ectA、ectB、ectC和ectD编码的酶可以催化对细胞起保护作用的四氢嘧啶类物质的生物合成,嗜盐菌新种Halomonas socia NY-011~T ectABC和ectD为四氢嘧啶和羟基四氢嘧啶的生产提供新的基因来源.通过SEFA-PCR步移方法从Halomonas socia NY-011~T中克隆ectA、ectB、ectC和ectD基因,并分别构建ectABC和ectD的原核表达质粒,在E.coli BL21(DE3)中异源表达,利用SDS-PAGE对重组蛋白进行鉴定,通过ACQUITY UPLC MS/MS检测四氢嘧啶和羟基四氢嘧啶的生成.结果显示:H.socia NY-011~T的四氢嘧啶合成基因ectA、ectB、ectC形成基因簇ectABC(KP717055-57),大小为2 506 bp,四氢嘧啶羟化酶基因ectD大小为942 bp(KP717058),与近源种H.elongata DSM258同源性分别为81%和78%;SDS-PAGE检测到4种融合蛋白,大小(M_r)分别为21.6×10~3、46.4×10~3、14.4×10~3、55.3×10~3,与预期相符;利用ACQUITY UPLC MS/MS发现仅表达ectABC的重组菌株[E.coli BL21(DE3)/pltac-ABC]中只存在四氢嘧啶,而在表达ectABC和ectD的重组菌株[E.coli BL21(DE3)/pltac-ABC/pETect D]中检测到四氢嘧啶和羟基四氢嘧啶.本研究从H.socia NY-011~T中分离得到的四氢嘧啶类物质的合成基因,能够在E.coli BL21(DE3)中异源表达并行使功能,为四氢嘧啶类物质异源生产提供了新的基因来源.     

化学农药对生态环境安全评价研究——Ⅺ.农药对天敌赤眼蜂的毒性与评价

本文阐述四种农药(三氯杀螨醇、氧化乐果、敌百虫和辛硫磷)对稻螟赤眼蜂和欧洲玉米螟赤眼蜂成蜂和四个发育期的毒性测定方法和安全影响。结果表明,同种等量农药对赤眼蜂成蜂的毒性最大,对四个发育期的毒性大小因农药品种而异,大体为预蛹期>蛹期>幼虫期>卵期。以LC_(50)与田间常用浓度的毒性比来评价农药对赤眼蜂的毒性等级;比值≥1者属高毒级,≤0.5者属低毒级,介于之间者属中毒级。     

水环境中典型抗生素SPE-UPLC-MS/MS检测方法的建立

应用固相萃取(SPE)及超高效液相色谱-串联质谱(UPLC-MS/MS)技术,建立了快速提取测定水环境中4种四环素类抗生素(四环素、土霉素、强力霉素、金霉素)和6种磺胺类抗生素(磺胺嘧啶、磺胺甲基嘧啶、磺胺二甲基嘧啶、磺胺二甲氧嘧啶、磺胺甲唑和磺胺噻唑)的方法.水样经过HLB小柱浓缩萃取之后以C18柱为分析柱,乙腈和0.1%甲酸水溶液为流动相,采用UPLC-MS/MS多反应监测(MRM)离子模式进行分析.纯水和城市生活污水中抗生素物质检出限分别为0.015—0.12 ng·L-1、0.03—0.09 ng·L-1,平均回收率分别为88.7%—113.5%、73.7%—94.5%,相对标准偏差均在2.6%—10.6%之间(n=8).方法操作简单、定性定量准确,检出限低,能够满足测定各类水环境中四环素类和磺胺类抗生素痕量残留的分析要求.     

高效液相色谱法测定畜禽废物中磺胺类、喹诺酮类抗生素

建立了一种荧光和紫外检测器串联同时测定磺胺类（磺胺甲基嘧啶、磺胺二甲嘧啶、磺胺对甲氧嘧啶、磺胺甲嗯唑）和喹诺酮类（诺氟沙星、环丙沙星、恩诺沙星）抗生素的高效液相色谱法．4种磺胺类、3种喹诺酮类抗生素分别在0．50—10．0μg·mL一、0．01—0．50μg·mL。范围内线性良好,相关系数R^2〉0．99．确定了最佳提...     

Mechanism of the uptake of metal cations by Algal Cell Walls

Nondisintegrated sprayed dried cells of Scenedesmus obliquus have been applied for the study of the cumulation of metal cations. It has been found that algal cell walls behave predominantely as polyfunctional weakly acidic cation exchangers. Equilibrium constants for different exchange reactions have been determined radiometrically which allow to calculate the form of algal cell walls in various experimental conditions. Metal cations present in microconcentrations may be cumulated predominantly by another cell wall ligands in comparison with the cumulation of macroconcentrations of the same cations.     

Organochlorine residues in the avifauna of Tamil Nadu (Southeast coast of India)

Pollution due to persistent pesticides is not a regional but a global problem. Organochlorine pesticides are persistent chemicals, stored and accumulated in the tissues of a wide variety of invertebrates and vertebrates including marine species. In the present study the organochlorine residues HCHs, DDTs and PCBs were measured in different trophic groups of birds (scavengers, inland piscivores, coastal piscivores, insectivores, granivores and omnivores) collected from Tamil Nadu Coast, India. The residue accumulation as a function of sex did not depict distinct variation. However, females had lower residue levels than males in terms of their mean weight and feeding habits. A continuous monitoring programme is recommended to establish the studied organisms as indicator species.     

Organochlorine residues in the avifauna of Tamil Nadu (Southeast coast of India)

Pollution due to persistent pesticides is not a regional but a global problem. Organochlorine pesticides are persistent chemicals, stored and accumulated in the tissues of a wide variety of invertebrates and vertebrates including marine species. In the present study the organochlorine residues HCHs, DDTs and PCBs were measured in different trophic groups of birds (scavengers, inland piscivores, coastal piscivores, insectivores, granivores and omnivores) collected from Tamil Nadu Coast, India. The residue accumulation as a function of sex did not depict distinct variation. However, females had lower residue levels than males in terms of their mean weight and feeding habits. A continuous monitoring programme is recommended to establish the studied organisms as indicator species.     

松前水稻（Oryzasativa cv.Matsumae）对土壤菲污染的生理生态响应

以松前水稻（Oryza sativa cv.Matsumae）为试验材料,研究了5种质量分数菲污染土壤对松前水稻营养生长期生长和生理生化指标的影响。结果表明：（1）菲质量分数低于20 mg·kg-1时促进茎直径的生长,随菲质量分数的增大对水稻苗期生长有明显的抑制作用。低质量分数和高质量分数的菲污染土壤对茎高和株高均有明显抑制作用,而中等质量分数影响不明显。（2）随菲质量分数的增大脯氨酸含量逐渐增大,而蛋白质含量均有不同程度的下降,植物体内存在着脯氨酸积累和蛋白质减少的反馈控制系统。（3）菲胁迫引起水稻叶片膜脂过氧化,植物体累积过量的丙二醛,且SOD活性受到不同程度的影响。（4）菲胁迫下,水稻营养生长期叶片叶绿素含量和光合作用速率无明显正相关关系。     

Essai d'utilisation de la diversité spécifique dans l'analyse des communautés de copépodes planctoniques du lagon de Nouvelle-Calédonie

During a one-year survey of the south-western part of the New Caledonian lagoon (February 1978–April 1979), zooplankton was sampled at eight stations representing different biotopes. This paper attempts to explain the regional dynamics of the copepod community by means of specific diversity (H) and its components: number of species (S) and evenness (H:H _max). For each station, cumulative samples were computed by progressively summing the successive samples. The diversities of these cumulative samples form a temporal-diversity spectrum. This spectrum is characteristic of the stability or variability of the population at each station. It appeared to be closely related to the date of the starting point of the cumulation. Therefore, a mean annual spectrum was calculated for each station, by averaging all the spectra obtained from different starting points. This mean annual-diversity spectrum offset seasonal variations, and seemed to be characteristic of the station's taxocoenose. It tended asymptotically towards the diversity of the yearly cumulated sample (composite sample made up of all samples collected during a year at the same station). In most cases, the spectrum tended towards this asymptote at lower values. However, at some stations, where a single species greatly outnumbered the others, the diversity of the yearly composite sample was lower than that of each individual sample. Thus, for these latter stations, the curve of the spectrum tended towards its asymptote at upper values. Rankfrequency curves were also used to reveal the distribution of individuals among species in the yearly cumulated samples, and proved to be very characteristic of the different stations. According to Legendre and Legendre, the number of species is a function of the stability of the environment and the evenness of the species' distribution is inversely proportional to the biological activity of the environment. A pattern of regional variations is proposed from the interpretation of the yearly averaged or cumulated indexes (H, S, H/H _max) at the different stations. Open-sea and mid-lagoon populations have almost equivalent diversities, but these diversities are not attained in the same manner. The open-sea population benefits from a stable (highly predictable) environment and has a great number of species; high interspecific competition, due to the scarcity of food, leads to a moderate evenness. In the less stable environment of the mid-lagoon, the number of available niches is lower, resulting in less species, but the greater abundance of food induces less interspecific competition and, consequently, high occupation rates of the niches available, i.e., high evenness. At the boundaries of its biotope, the mid-lagoon population suffers two kinds of stress: terrestrial run-off near the cost and turbulence from breakers, and predation by plankton-feeders around the barrier reef. These stresses decrease both species richness and evenness. Elimination of most species results in the dominance of Acartia amboinensis in a deep, fjordlike river mouth, and of A. australis in the reef areas. The mixing of lagoon and open-sea plankton in the vicinity of the channel is reflected by an inflection point in the frequency-rank curves. The outcome of these exchanges is probably an exportation of plankton from the lagoon towards the open sea. This may be viewed as an exploitation of the lagoon ecosystem by the open-sea ecosystem, inhibiting a full maturation of the former.     

不同陈化烟叶叶面高温微生物多样性

以国内外不同品种、不同陈化时间的10个烟叶样品为材料,对其叶面高温微生物进行了分离纯化、鉴定和多样性研究,以了解表面高温微生物在烟叶陈化发酵中的作用.结果表明:陈化烟叶表面高温菌总量为103~105个/g,高温细菌占绝对优势,真菌很少,未能分离到放线菌和酵母菌;高温细菌主要包括芽孢杆菌属(Bacillus)和地芽孢杆菌属(Geobacillus)两个属,芽孢杆菌属为优势菌属;高温霉菌主要包括青霉属(Penicillium)和曲霉属(Aspergillus),曲霉属为优势菌属.国内外烟叶表面微生物种类和数量有所差异,与陈化时间和烟叶品种等因素有着密切关系.     

荔枝、龙眼和香蕉质量与生产环境的关系

对广州市的荔枝、龙眼和香蕉三大类水果产品质量和生产环境进行了质量监测和评价。结果表明,这三类水果的生产环境均遭受一定程度的污染;水果质量广泛受到氟污染,部分受到Pb、Cd污染;荔枝对镉的吸收富集作用较强。     

威海市区黑松林群落分析的研究

根据威海市区黑松林的调查结果,分析了该群落的组成和结构特征。在11500m2的样地里有维管束植物105种,它们隶属于39科89属,其中被子植物37科;裸子植物1科;蕨类植物1科。该群落以单种科和寡种科占绝大多数,单种属有75种,占总数的71%,种数大于2的有13科,占总数的33%。该群落分为乔木层、灌木层及草本层3个层次,乔木层主要以黑松Pinusthunbergli、麻栎QuercusacutissimaCarr.等种类组成,灌木层主要以麻栎组成,草本层种类较少,以禾本植物为主。该群落中、高位芽植物占优势,缺乏隐芽植物。叶型以中、小型叶为主,缺乏大型叶植物。TWINSPAN将115个样方分为11个群落类型。调查结果表明本地区黑松林群落结构简单,不同黑松林群落结构差异较小,且物种丰富度低,是人为干扰强烈所致。     

The investigation of metal concentrations in street dust samples in Aqaba city,Jordan

The concentrations of metals (Fe, Zn, Cu, Cr, Pb, Cd, Ni, Mn and Co) in 140 street dust samples were collected from Aqaba city, Jordan. These samples were determined using flame atomic absorption spectrophotometry after digestion with aqua regia. The highest levels of metal concentrations were found in the samples from heavy traffic. While the lowest levels of metal ions were noted in the street dust samples from hospital and health centers and school gardens. The results of this study were compared with several cities around the world. The levels of the metal concentrations found were generally below the mean world-wide values of street dust samples. Metal values in urban street dust samples were several times higher than the control levels. The statistical analyses were applied to the data matrix to determine the analytical results and to identify the possible source of pollution in the studied area. Correlations between the metal concentrations of the street dust samples were obtained. Factor analysis showed that the area was mainly influenced by three sources, namely lithogenic, traffic, and industrial.     

江汉平原农村食品中农药残留研究

研究了湖北省潜江市农村６类食品中农药的残留情况,采样测定结果表明,在被检食品中有机氯农药污染普遍存在,但残留量均低于最大残留限量（ＭＲＬ）,以植物油残留量为最大;有机磷农药残留只在蔬菜中检出,检出率以根菜类为最大,叶菜类次之,果菜类和花菜类最小;菊酯类农药残留较少;杀菌剂多菌灵残留未检出。