棉花黄萎病抗性鉴定新方法——无底塑钵菌液浇根法

通过一系列的试验 ,笔者发展了一种快速鉴定棉花品种抗黄萎病性能的新方法—无底塑钵菌液浇根法 ,此法比传统的纸钵撕底醺根法更简便 ,发病较轻 ,能准确客观地反映品种的抗性     

厩肥对粉煤灰微量元素释放规律影响的研究

该文对粉煤灰在降雨淋洗条件下微量元素的释放规律进行了室内模拟试验。试验处理分别为粉煤灰、粉煤灰+石灰、粉煤灰+石灰+厩肥及其混合物的堆肥腐熟4种情况。实验结果显示淋出液中B、Sr、Ba和Li的最大浓度大于1 mg/L，而其它元素均小于此值。石灰的应用增大了淋出液中B和Ba的浓度而降低了Li、Mo和Cr的浓度；厩肥的应用及其堆肥腐熟处理增大了B、Mo、Zn、V以及Cu、Ni、Cd、As、Mn、Ti、Co、Sn和Se的浓度，而降低了Sr、Ba、Li和Cr的浓度。除V外，淋出液中所有微量元素的浓度随淋出液体积的增加而减小。Cr、Zn以及Cd、Cu和As可能是粉煤灰对环境产生潜在危害的主要元素。     

螺纹铣削工艺的选择

总结了在数控加工中心上进行螺纹铣削的一些注意事项,其中包括螺纹铣削刀具的选用及测定、螺纹铣削底径的确定、铣削方式的选择及精度控制等。     

Composition,distribution and sources of polycyclic aromatic hydrocarbons in sediments of the western harbour of alexandria,egypt

Aim and Background  Little data are available on the levels of polycyclic aromatic hydrocarbons (PAHs) in the sediments of the Mediterranean Sea Coast of Egypt in general and the Alexandria coastal zone in particular. It was therefore deemed necessary to set up a monitoring programme to determine the current concentrations of PAHs in bottom sediments, and to identify any area where high concentrations of these potential hazardous contaminants were present in the Western Harbour of Alexandria. Methods  The composition, distribution and the source of PAHs in surficial sediments of the harbour were investigated. To document the spatial PAH input, surficial sediment samples from 23 locations throughout the harbour were analysed. as]Results and Discussion The total PAH load determined in the surficial sediment samples ranged from 8 to 131150 ng g¹ dry wt, generally with most of the samples having total concentrations of PAHs greater than 5000 ng g¹ dry weight. The highest concentration of total PAHs was recorded in sediments of the inner harbour. Ratio values of specific compounds such as phenanthrene to anthracene, fluoranthrene to pyrene, methyl-phen-anthrene to phenanthrene, methyl-dibenzothiophenes to dibenzothiophenes, alkylated to non-alkylated and high molecular weight to low molecular weight PAH, were calculated to evaluate the possible source of PAH contamination in the harbour sediments. Conclusions  Two main sources of PAH in the study area have been found: pyrolytic and petrogenic. Interferences of rather petrogenic and pyrolytic PAH contaminations were noticed for most samples. The dominant sources of PAH appear to be the combustion processes through run-off, industrial and sewage discharges, and atmospheric input. The concentrations of PAHs were generally above levels expected to cause adverse biological effects. Recommendations and outlook  Information from this study and any other relevant studies should be useful in designing future strategies for environmental protection and management of the harbour.     

光诱鱿鱼浮拖网渔具渔法试验

首先对诱鱼光场进行计算，并分析其对光诱鱿鱼浮拖网作业的影响，据此合理配置了灯光强度及其布局，探讨了一套较有效的诱导渔方法。根据鱿鱼的趋光习性及浮拖网的特点，设计了适应在较深渔场作业的光诱浮拖网渔具，并成功地试验了光诱鱿鱼浮拖网柔性网板；取得了良好的社会生态效益和经济效益。     

智利竹鱼拖网最适网囊网目尺寸探讨

根据拖网网囊网目尺寸与鱼体生物学存在关系 ,对智利竹鱼的优势叉长组成、形体特征、初次性腺成熟时的叉长等进行了分析。通过现场测试得出 2 0 0 0年智利竹鱼的优势叉长为 2 5 0～ 30 0mm ;体高、体宽和体周与叉长存在线性关系 ,分别为 2a =0 .185 8L - 3 .5 2 19,2b =0 .1339L - 4.2 99,c =0 .480 3L - 3 .4794。并对智利竹鱼拖网网囊网目尺寸进行了分析与计算 ,认为智利竹鱼拖网网囊的最适网目内径为 115～ 12 0mm。     

单层不等高厂房横向抗震分析

以单层不等高厂房为研究对象,分别采用简化的底部剪力法和精确的振型分解反应谱法对其横向抗震性能进行计算分析。结果表明,采用现行规范中的底部剪力法及相应修正系数、公式,进行不等高厂房横向抗震分析时误差过大,建议采用较为精确的振型分解反应谱法。     

原油罐金属底板的腐蚀与防护

针对原油罐区的腐蚀现状，分析了原油罐底板的腐蚀机理，通过对原油一罐的腐蚀调查、底板测厚，以及对罐底脱水中腐蚀介质及沉积物样的化学分析，提出了使用WF－50防腐涂料加阴极保护的方案，该方案可有效地防止原油罐金属底板的腐蚀。     

Assessment and selection of fungal antagonists against Rhizoctonia solani

The soil-borne pathogen Rhizoctonia solani Kühn (teleomorph, Thanatephorus cucumeris [A.B. Frank] Donk) is worldwide responsible for serious damage of many economically important agricultural and horticultural crops. Control of Rhizoctonia diseases is difficult because this pathogen survives for many years as sclerotia in soil or as mycelium in organic matter under numerous environmental conditions. Furthermore, the pathogen has an extremely wide host range. To date, no effective con…     

芜湖市镜湖底泥TN、TP、重金属污染及其对上覆水体的影响

采集镜湖底泥及水样,研究底泥中重金属的污染现状,分析底泥TN、TP重金属与上覆水体相同成分的相关性,结果表明：（1）镜湖底泥TN、TP与水体TN、TP含量呈有著相关性,底泥N？P释放再悬浮是镜湖水体TN、TP来源之一。（2）镜湖除Cd严重超标外,Cu？Zn？Pb含量都很低;Cd（n）与Cd（w）有较好的负相关性,Cu（n）与Cu（w）？Zn（n）与Zn（w）？Pb（n）与Pb（w）相关性差。本研究为有关部门治理和管理镜湖提供理论依据。