甲苯侧链催化氯化产物分布的研究     

唐薰  邓凤其 《湖南农业大学学报(自然科学版)》1996,23(6)

研究了催化氯化的产物分布，试验了有关条件对产物分布的影响。结果表明：氯化程度是产物分布的主要影响因素；温度的提高，有利于苄叉二氯和苄川三氯的生成；铁离子、低温及水会导致环上的氯化；水引起水解的发生。  相似文献   

试论含氯化肥的合理施用   总被引：1，自引：0，他引：1  

阎相奎 《甘肃农业大学学报》1993,28(1):99-103

根据氯对作物和土壤的影响,表明南方可以在各种作物的耐氯极限内施用含氯化肥,并需配合施用石灰和含钙磷肥;而北方旱区,特别是西北地区合理施用含氯化肥应根据每茬作物吸收带走的氯量,确定一个轮作周期内施用含氯化肥的量,保持土壤氯素的平衡,不致使土壤盐渍化。氯化铵可以就近施用,缺钾作物也能以含氯钾肥予以补充。此即本文所述氮素平衡施肥原理。  相似文献   

Efficacy of chlorine dioxide gas in reducing Escherichia coli and Salmonella from broiler house environments     

《The Journal of Applied Poultry Research》2017,26(1):84-88

Escherichia coli and Salmonella spp. are considered to be the major pathogens associated with human transmissible infectious diseases in the air of poultry houses. Chlorine dioxide (ClO₂) is an effective biocide against a wide range of microorganisms. Accordingly, this study investigated the efficiency of gaseous ClO₂ application for disinfecting broiler houses by collecting air samples before and after fumigation using a passive method. Fumigation was performed with 125 mL or 250 mL of ClO₂ liquid (containing 2,000 ppm of ClO₂) and 3 trials were conducted for each dose. A total of 27 petri dishes were used for each trial (for each type of bacteria: E. coli or Salmonella) and placed in 3 different locations (front, middle and back) and 3 different positions (top, middle and floor) of the broiler shed. Air samples were collected at 10 min, 1 h, 3 h, 6 h, and 12 h before and after fumigation to evaluate the air quality in terms of the concentration of E. coli and Salmonella. Both levels of ClO₂ were capable of reducing the concentration of E. coli from broiler house air during all measuring periods except 10 min, with highest disinfection rate being observed at 6 h. With the exception of 1 h, the concentration of Salmonella was also reduced after fumigation with ClO₂ in all measuring period; with the highest disinfection rate occurring at 6 h. Fumigation with ClO₂ had no negative effect on birds’ health condition. Taken together, these results suggest that the application of gaseous ClO₂ at the investigated levels can be an effective option for reducing bacterial load from broiler house environments.  相似文献   

Application of chlorine dioxide to lessen bacterial contamination during broiler defeathering     

《The Journal of Applied Poultry Research》2011,20(1):33-39

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施用生物菌剂对烤烟叶片生理特征及钾、氯含量的影响     

毛家伟  张翔  李亮  余琼  司贤宗  索炎炎  吴俊林  孔德辉 《干旱地区农业研究》2020,38(3):181-187

为探讨不同生物菌剂在烤烟上的施用效果,选取烤烟品种秦烟96和豫烟6号为材料,设计了对照(T1)、生物菌剂A(T2)、生物菌剂B(T3)、生物菌剂C(T4)、生物菌剂D(T5)和生物菌剂E(T6)6个处理,于2016年在河南省洛阳市(旱作烟区)和驻马店市(雨养烟区)进行了田间试验,研究了施用生物菌剂对烤烟叶片生理特征及钾、氯含量的影响。结果表明:施用生物菌剂处理与对照相比烤烟叶片中可溶性糖的含量增加了0.38%～1.43%,丙二醛(MDA)含量降低了0.3～7.36μmol·g~(-1)。除雨养烟区T5处理外,与对照相比,施用生物菌剂处理烤烟叶片过氧化氢酶(CAT)活性、超氧化物岐化酶(SOD)活性和过氧化物酶(POD)活性分别提高2.1～26.2μmol·min~(-1)·g~(-1),0.6～40 U·g~(-1)和546～2 531 U·g~(-1)。中部叶养分分析表明,施用生物菌剂处理在移栽后45 d(除雨养烟区T4处理外)全钾含量提高了0.42%～1.32%,移栽后60 d提高了0.03%～1.00%。从经济性状看,与对照相比,雨养烟区T3处理产值和上等烟比例分别增加14 708元·hm~(-2)和23.1%,旱作烟区T2处理产值和上等烟比例分别增加7 849元·hm~(-2)和13.7%。化学成分分析表明,雨养烟区T3处理和旱作烟区T2处理烟叶钾含量平均分别提高0.40%和0.57%,施用生物菌剂处理使烟叶化学成分更加协调。  相似文献   

二氧化氯对池塘水质和浮游生物群落结构的短期影响     

董加沙  何绪刚  邓闵  覃雅  刘全圣  陈荣 《淡水渔业》2016,(2):74-81

监测了公安县崇湖渔场3口草鱼主养池塘施用浓度为0.375 g/m3的二氧化氯后池塘水质理化指标及浮游生物群落结构短期变化,以分析二氧化氯对池塘水环境质量的影响。结果显示,用药后水体溶解氧显著下降,亚硝态氮、活性磷和总磷降低。然而p H值显著升高,硝态氮、铵态氮和总氮也有所升高。施用二氧化氯前浮游植物共检出6门44属79种,浮游动物36属43种;用药后共检出浮游植物7门52属109种,浮游动物44属69种,用药后浮游植物消失4属12种,新增加12属42种,用药前未见金藻门种类,用药后出现分歧锥囊藻(Dinobryon divergens)。用药后原生动物消失6属7种,新出现16属24种;轮虫消失3种,增加8种;枝角类种类无变化;桡足类新增4种成体,但用药前后优势种无变化。结果表明,施用二氧化氯短期内增加了水体氨氮毒性,并导致浮游动物的种类、密度和生物量显著增加,进而导致浮游植物生物量显著下降、小型化藻类增多、优势种显著变化。建议在养殖期间慎用二氧化氯。  相似文献   

Toxicity of chlorine to different sizes of black tiger shrimp (Penaeus monodon) in low-salinity shrimp pond water     

Husnah  & Chang Kwei Lin 《Aquaculture Research》2002,33(14):1129-1135

An experiment was conducted, in a dark room with controlled temperature (27.3–28.4 °C), to determine the acute toxicity of chlorine concentration to black tiger shrimp (Penaeus monodon fabicus) of sizes 0.02 g, 2.75 g, 8.47 g and 23.65 g. Toxicity tests on each of these shrimp sizes were run in triplicate in glass jars under static conditions without media renewal. The concentration of active chlorine that killed 50% of the shrimp of each size after 24‐h exposure (LC₅₀‐24 h) was used as an indicator of acute toxicity. Chlorine concentrations applied in the shrimp toxicity test ranged from 2.0 to 14.5 mg L^?1 in shrimp pond water. As the test water contained total suspended solids of 22.0–85.0 mg L^?1 and total ammonia nitrogen of 0.18–0.40 mg L^?1, the resultant concentrations of combined residual chlorine ranged from 0.6 to 3.5 mg L^?1, which were the effective doses causing shrimp mortality. The test results showed that 24‐h LC₅₀ for average shrimp size at 0.02, 2.75, 8.47 and 23.65 g occurred in water containing combined residual chlorine at a concentration of 0.91, 1.39, 1.74 and 1.98 mg L^?1, for which the original application doses were 6.96, 2.05 11.50 and 13.34 mg L^?1 respectively.  相似文献   

EFFECTS OF FOLIAR AND SOIL CALCIUM APPLICATION ON YIELD AND QUALITY OF TABLE GRAPE CV. ‘THOMPSON SEEDLESS’     

Claudia Bonomelli  Rafael Ruiz 《Journal of plant nutrition》2013,36(3):299-314

Table grape quality and firmness are key parameters for Chile's export, given distances from the main markets. As a consequence, calcium (Ca) fertilization has become a standard practice in the country, although its effects have not been fully evaluated. The objectives in this study were to investigate the effects of calcium fertilization on table grape nutrition and quality. A two-year field trial was conducted in central Chile, using grapevines (Vitis vinifera) cv. ‘Thompson seedless’, grown on an overhead trellis system. Calcium (CaCl₂) application treatments included foliar, soil, foliar plus soil, and a control without Ca fertilization. Calcium and other nutrients concentration were determined afterwards in soil, leaves, and berries. Also, yield and some fruit quality parameters were evaluated. Calcium application method did not have an effect on soil, leaf or fruit Ca content, neither on yield and berry sugar concentration, with levels being similar to the control treatment. Additionally, in treatments where CaCl₂ was applied to soil, chlorides concentration in soil, leaves, and berries were higher. Also, berries were larger, more turgent, with lower dry matter and larger cells. In the second season, in these same treatments, berry firmness at harvest was higher, but this effect disappeared after the storage simulation period. These results question the validity that Ca applications might improve table grape postharvest quality for growing conditions similar to the ones in this experiment. The temporal changes in berry quality parameters were attributed to higher Cl soil content and the associated plant osmoregulatory mechanisms.  相似文献   

电解与紫外协同去除工厂化养殖循环水中氨氮效果研究     

吴照学  李海军  杨智良  裴洛伟  朱松明  叶章颖 《农业机械学报》2016,47(4):272-279

为探究电化学氧化法在工厂化循环水养殖系统中处理水质的效果及影响因素,在前期试验得到最佳条件(温度25℃、电流密度40 A/m2、水流速度300 m L/min)下,以不同初始氨氮质量浓度和固体悬浮颗粒物的模拟养殖水以及实际养殖水为研究对象,探讨了加入低压紫外汞灯后电解与紫外协同去除氨氮的效果。结果表明:电解紫外协同处理氨氮效果明显优于单独电解法,运用本系统处理氨氮初始质量浓度分别为4、7、10 mg/L的模拟养殖水时,氨氮去除效率相对于单独电解时分别提高45.0%(p0.05)、36.0%(p0.05)和20.0%(p0.05);电解紫外协同去除氨氮效率受氨氮初始质量浓度、水体中的固体颗粒悬浮物、实际养殖水等因素影响,随着氨氮初始质量浓度及水体中固体悬浮颗粒物的升高,氨氮的去除效率降低,达到同种去除效率所需的时间延长,当处理固体悬浮颗粒(SS)分别为100、150、200 mg/L的模拟养殖水时,氨氮的去除效率随着SS的升高而降低,相对于仅含氨氮的模拟养殖水,氨氮的去除效率分别降低51.7%(p0.05)、65.5%(p0.05)和72.4%(p0.05);在处理实际养殖水时,氨氮的去除速率明显降低,去除完全所需的时间延长,在本系统中电解紫外对氨氮、亚硝氮、固体悬浮颗粒物的去除具有较好效果,去除率分别为97.8%、96.9%和92.1%。  相似文献   

半干旱地区果园土壤Cl-迁移积累与环境因子的关系     

郭全恩  王益权  郭天文  马忠明  刘军  南丽丽 《核农学报》2009,23(5):853-857

为揭示环境因子对果园表层土壤氯离子迁移累积的影响,为预防和改良土壤次生盐渍化提供理论指导和相关依据,研究果树生育期表层土壤不同土层氯离子的变化与环境因子（土温、土壤水分、蒸发量、降雨量、水分亏值、气温、空气相对湿度）的相互关系。结果表明：在土壤0~25cm土层的微域范围内,不同土层对氯离子的迁移与累积具有不同的功能。0~5cm土层为氯离子聚集层,10~15cm土层为氯离子传导层。认为10~15cm土层是半干旱地区环境因子对土壤性质直接作用与影响的临界深度。  相似文献