Independent Risk Factors Predicting Gradual Onset Injury in 2824 Trail Running Race Entrants: SAFER XVIII Study     

《The Forestry Chronicle》2021,32(3):293-301

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设施农田土壤重金属污染评价及分区阈值研究     

曹志强  韦炳干  虞江萍  孟敏  李海蓉  杨林生  尹舒慧  李峰  张国印  陈清 《农业环境科学学报》2020,39(10):2227-2238

设施农田高强度的耕作模式使土壤重金属累积日益加重，因地制宜地确定其土壤重金属目标值与筛选值对设施农田可持续生产意义重大。本文以石家庄、衡水与唐山为研究区，基于土壤重金属污染风险和生态风险评价，用熵权法得出综合风险等级并确定重金属污染分区阈值。结果表明土壤Cd、Cu、Zn污染最严重，高风险区占比达40.57%。研究区设施农田土壤Cd、Cu、Pb、Zn全量与有效态的目标值分别为0.12、40.17、19.23、116.03 mg·kg^-1与0.02、4.19、0.59、8.80 mg·kg^-1；筛选值分别为0.40、90.27、38.33、170.68 mg·kg^-1与0.11、11.77、1.55、14.24 mg·kg^-1。基于综合评价结果反推分区阈值的方法简单便捷，重金属全量与有效态的目标值及筛选值的确定为研究区设施农田重金属污染的预防提供了多方位的指导。  相似文献   

河西走廊戈壁温室番茄无土栽培基质筛选     

贾靓  陈修斌  李翊华  许耀照 《蔬菜》2020,(6):53-56

为提高番茄无土栽培质量,以番茄品种"金福莱"为试材,研究了6种不同配比基质对河西走廊温室无土栽培番茄生长的影响。结果表明:采用处理Ⅳ(沙∶玉米秸秆∶食用菌下脚料∶商品基质∶鸡粪=4∶5∶5∶6∶3)的基质配比(体积比),番茄光合速率、蒸腾速率、胞间CO_2和气孔导度数值最大,植株保持较强的生长势与结果能力,番茄株高、茎粗、单株结果数、单株产量和折合667 m~2产量等性状均显著优于其他处理,分别为178.60 cm、1.13 cm、16.36个、3.12 kg和7 531.68 kg;其果实的可溶性糖、可滴定酸、可溶性固形物、VC和番茄红素含量最高,分别为4.15%、0.58%、7.30%、302.2 mg/kg和152.4 mg/kg,明显优于其他处理;因此,在河西走廊戈壁温室番茄无土栽培中推荐使用此配比基质。  相似文献   

Rapid screening of genetically modified ingredients in soybean and cotton processing by-product and waste using direct qPCR     

《中国油料作物学报(英文)》2020,5(3):142-148

To develop a simple and fast method for screening genetically modified ingredients from processing by-product and waste, direct quantitative PCR (qPCR) kit-Taqman which omitting multi genomic DNA preparing steps was developed in this study. A total of 18 oil crop processing by-products and wastes including 10 soybean and 8 cotton materials were collected from food processing factories. Compared with 2 commercial direct qPCR kits, conditions of DNA releasing procedure and PCR amplification were optimized. Element screening was performed at the initial step of genetically modified (GM) ingredient testing procedure via direct qPCR. GM event identification was carried out in positive samples by initial screening. Totally 5 screening elements (P–35S, T-NOS, Cp4-epsps, bar and pat) for soybean materials and 6 screening elements (P–35S, T-NOS, NPTII, Cry1Ac, bar and pat) for cotton samples were detected. In GM event identification, MON531 and MON1445 were found in cotton materials. Results were further confirmed by real-time PCR with DNA extraction and purification. The direct qPCR system proposed by this research was convenient for rapid screening and identification of GM ingredients in oil crop primary by-product and waste.  相似文献   

Advances on Detection Methods for Residues of Nitrofurans in Food     

WANG Ming-ming  XU Na  TANG Yun  HANG Ye  LIU Zhen-jiang  DU Dao-lin 《中国畜牧兽医》2016,43(8):2202-2207

Nitrofurans are broad-spectrum antibiotics which have been widely used in food animals to the prevention and treatment of gastrointestinal infections.Due to abuse of drugs by criminals,animals could produce drug-resistant strains,which reduces the role of antibiotics.Meanwhile,excessive drugs residues in food has carcinogenic,teratogenic and mutagenic effects to the human body.In this paper,the damage and the detection methods of the residues of the nitrofurans in food are surveyed.The main detection methods include high performance liquid chromatography,liquid chromatography-mass spectrometry,liquid chromatography tandem mass spectrometry,enzyme-linked immunoassay,colloidal gold immunoassay and fluorescence immunity analysis method.The research status of various detection methods are summarized and the suggestions for further research are put forward.It is expected to provide reference for future research.  相似文献   

增强学生对“作物栽培学实验”学习兴趣的探讨     

李飞飞  何少海  丰宇凯 《安徽农学通报》2016,(8):150-151

该文根据在作物栽培学及其实验的教学过程中的心得体会,从实验教学内容和模式、教学手段、教学方法及考核办法等几个方面展开论述,总结了如何增强学生对该实验课程的学习兴趣,以便更好地改善教学质量。  相似文献   

基于响应面法和NSGA-II算法的麦弗逊悬架优化     

李伟平  王世东  周兵  张利轩  马义超 《湖南农业大学学报(自然科学版)》2011,38(6):27-32

应用响应面法和经过改进的非支配排序遗传算法(NSGA-II)进行悬架结构参数优化.在ADAMS/Insight软件中进行设计参数的灵敏度分析，针对灵敏度较大的设计参数，建立车轮定位参数在车轮跳动过程中最大变化量的2阶响应面近似数学模型对该模型进行稳定性分析，并且应用加入精英保持策略和去除重复个体算法的NSGA-II优化算法对多目标响应面模型进行优化求解.优化结果表明该方法具有较高的精确性与有效性.  相似文献   

新疆核桃腐烂病拮抗菌的筛选及鉴定   总被引：1，自引：0，他引：1  

张晶晶  李建贵  郭艺鹏  韩超  秦韵婷 《经济林研究》2016,(1):71-75

为给核桃促生菌群的构建提供菌株材料,通过对新疆核桃拮抗菌的分离纯化,筛选出对核桃腐烂病病原菌具有拮抗作用且能在其根际稳定定殖的优质高效菌株。从阿克苏、和田、喀什等新疆核桃主产区的根际土壤中分离出拮抗菌30株,采用对峙试验法对其拮抗能力进行测定,选出拮抗菌14株。经耐利福平诱导后剩余7株。将其进行大田定殖试验后,最终筛选出7株拮抗菌。经16S r DNA鉴定,这7株拮抗菌属于3个属,分别为假单胞菌属Pseudomonas、芽孢杆菌属Bacillus、链霉菌属Streptomyces,其中假单胞菌属为优势种属,且拮抗效果及稳定性最好。  相似文献   

《园林设计初步》课程教学探析     

冯丽 《热带作物学报》2011,31(4):92-95

《园林设计初步》是园林专业的基础课。针对目前《园林设计初步》教学存在的问题，结合《园林设计初步》课程定位及特点，围绕制图基础、设计基础及设计入门三大教学内容，从理论教学和实训教学两个方面，提出当前形势下《园林设计初步》教学内容安排及教学方法，以期提高教学效果。  相似文献   

10种杀细菌剂对火龙果细菌性茎腐病菌的毒力测定     

赵世学  符碧海  戴进  朱朝华  谭志琼  张荣意 《中国果业信息》2016,45(2)

采用抑菌圈法，对10种杀细菌剂在火龙果茎腐病病原上进行了毒力测定。结果表明：72%农用硫酸链霉素可溶粉剂、53.8%氢氧化铜水分散颗粒剂（杜邦TM）、45%代森铵水剂、47%春雷?王铜可湿性粉剂、50%福美双可湿性粉剂和3%中生菌素可湿性粉剂对火龙果茎腐病病原均有一定抑制效果。其中，45%代森铵水剂和50%福美双可湿性粉剂防治效果较好，抑制率分别达到78.88%和71.42%，其直线回归方程分别为y=2.380 2.477x，y=2.896 1.146x，EC50分别为0.4929，0.0240。72%农用硫酸链霉素可溶粉剂效果次之，抑制率达到66.67%，直线回归方程为y=1.020 1.040x，EC50值为2.5686。这3种药剂可作为火龙果茎腐病田间药效试验的首选药剂。  相似文献