表面活性剂强化EDTA络合洗脱污灌土壤中重金属的试验研究

在实验室条件下研究了表面活性剂十二烷基硫酸钠(SDS)、聚氧乙烯月桂醚(Brij35)和重金属洗脱螯合剂EDTA对土壤中Cd、Pb的解吸去除作用,同时研究了加入SDS和Brij35后对EDTA解吸污染土壤中Cd、Pb作用的影响,并对解吸前后重金属在土壤介质中形态变化进行了测定。结果表明,加入表面活性剂SDS可使EDTA对Cd的解吸量由61.67%增加到79.68%、对Pb的解吸量由57.25%增加到89.65%。在EDTA浓度较小时,加入SDS对Cd、Pb的解吸产生拮抗作用,抑制了EDTA对污染土样中Cd、Pb的解吸;随着EDTA浓度的不断增加,加入SDS与EDTA产生明显的协同增溶作用;表面活性剂Brij35具有相同的增溶作用,但增溶效果不如SDS。比较复配解吸前后重金属形态变化,可溶态、碳酸盐结合态较解吸前减少60%￣90%,大大降低了污灌土壤中重金属的毒性和生物可利用性。试验结果可为利用表面活性剂与EDTA复配提高重金属在土壤介质中的解吸率提供理论依据,并可应用于污灌土壤中重金属的冲洗治理。     

马铃薯新品种冀张薯24号的选育研究

冀张薯24号是由冀张薯8号作母本、ELLES作父本配制杂交组合,经系谱法选育而成的马铃薯新品种。该品种属晚熟加工型,植株直立,长势强且整齐,茎绿色,叶深绿色,花冠紫色,薯型卵圆形,浅黄皮白肉,薯皮微麻,芽眼浅。干物质含量20.82%,淀粉含量15.14%,还原糖含量0.26%,粗蛋白含量2.69%,维生素C含量265.6mg·kg^-1。抗PVY、PVX、PLRV、PVA、PVM病毒病,中抗晚疫病、早疫病。2018年8月30日通过中华人民共和国农业农村部非主要农作物品种登记,登记编号:GPD马铃薯(2018)130077。     

刈割对青海早熟禾再生性的影响

通过对青海草地早熟禾不同刈割强度下再生性的研究,结果表明:刈割高度与频度不同,牧草再生能力不同。低茬高频的刈割,即留茬高度5cm、刈割频度7天/次,青海草地早熟禾再生性达到最佳水平,产草量也随之增加。     

白牦牛早期胚胎发育条件的初步研究

研究了卵母细胞质量和体外受精卵培养温度对白牦牛早期胚胎发育的影响。结果表明:白牦牛体外受精时要选择A级质量的卵母细胞,体外受精胚胎发育的最适温度为38℃。为完善白牦牛胚胎的体外生产体系提供了实验依据。     

雷琼牛肌肉生长抑制素基因序列研究

通过PCR方法对18头雷琼牛的MSTN基因进行扩增、测序.编码区序列分析结果表明:雷琼牛MSTN基因比外域瘤牛存在较丰富的多态性,共发现4个突变位点(2个转换,2个颠换),定义了6种单倍型,群体单倍型多样性较高(0.810±0.057);分析结果表明:MSTN基因的相关突变的发生可能早于Bos属瘤牛、普通牛、牦牛的分化;在瘤牛种内,我国南方的瘤牛可能是更原始的种群.     

乡镇基层农机科技推广工作探讨

乡镇基层农机科技推广工作存在着诸多的问题:思想观念滞后、制度不健全、示范力度不足、资金投入少以及农机与农艺融合欠缺等,这些问题必须得到行之有效地解决,否则直接阻碍我国农业现代化的实现。具体解决对策有:增强为广大农户服务的理念,强化科技人才队伍建设,加大科技成果转化率、增加资金投入,创建农机新技术的推广信息网络平台等。     

Can sieving size affect the determination of soil available micronutrients?

<正>Dear Editor,Globally, approximately two billion people suffer from micronutrient deficiencies(Tulchinsky, 2010; Myers et al.,2014).Soil micronutrient availability is of great importance for the evaluation of soil fertility and the determination of appropriate measures for improving crop quality and human health.The diethylenetriamine-penta-acetic(DTPA)     

鸭种蛋孵化工艺的优化

1 种蛋的收集、消毒与保存 1.1 种蛋的收集 种鸭与种鸡所处的环境有所不同,鸭离不开水,因此鸭舍比鸡舍脏,种鸭一般在凌晨3:00左右产蛋,如不及时收集种蛋,易被种鸭践踏造成污染,所以收集种蛋应越早越好.在收集时应按种用蛋、非种用蛋(双黄蛋、破蛋、畸形蛋)分别装入专用鸭蛋篓.早晨6:30产蛋基本结束,第一次集蛋完成后应尽快入库.有个别的种鸭产蛋(约占母鸭群的3%左右)直到上午8:00左右产蛋才结束,应将第二次集好的种蛋再送到蛋库.     

拮抗菌株PM-1发酵条件研究

拮抗菌株PM-1对黄瓜灰霉病具有较好的抑菌效果,100μl发酵液对黄瓜灰霉病抑菌圈直径可达到30mm,菌株PM-1产抗生素最适培养条件为：接种量为装液量5％,28℃,240rpm、pH为7、装量体积为容器容积1／5以及发酵培养4d（96h）。     

Adverse events associated with pericardiocentesis in dogs: 85 cases (1999–2006)

Objective – To quantify the frequency of adverse events occurring during or post pericardiocentesis and to determine if adverse events are related to the cause of the pericardial effusion or frequency of pericardiocentesis.
Design – Retrospective study.
Setting – Referral hospital.
Animals, Intervention and Measurements – Medical records of 85 dogs that underwent 112 episodes of pericardiocentesis were reviewed. Any adverse events during pericardiocentesis and in the 48 hours post pericardiocentesis were noted. The frequency of adverse events was compared between dogs with a suspected neoplastic cause and a suspected nonneoplastic cause of their pericardial effusion and also between the first and subsequent pericardiocenteses.
Main Results – The incidence of adverse events was 10.7% within 1 hour of pericardiocentesis and 15.2% within 48 hours. There was no significant difference in the frequency of adverse events between the groups. Most adverse events identified were dysrhythmias. Forty-one percent of those dogs with adverse events were euthanized or died within 48 hours.
Conclusion – The incidence of adverse events seen within 48 hours of pericardiocentesis was 15.2%.