畜牧业生产中的环境污染及治理对策   总被引：22，自引：3，他引：19  

张文龙  王建彬等 《家畜生态》2001,22(3):51-55

本文阐述了畜牧业生产中产生的畜禽粪尿、有机废水等废弃物对环境造成的污染，探讨了治理畜牧业污染的措施，提出了发展生态畜牧业的思路。  相似文献   

红曲霉色素的提取     

张文芳  蒋光正  李薇  刘若男 《东北农业大学学报》1990,(1)

本实验确立了一种新的红曲霉色素提取方法:以红曲米为原料,乙醇为提取剂,得到的提取液再以正己烷提取分离。结果表明,此法所得的红曲霉色素是水溶性的,宜于用作食品添加剂。此外,还对影响提取的因素进行了探讨,并提供了最佳提取方案。  相似文献   

Outcome of limb amputations in wapiti: 13 cases (1995-2001).          下载免费PDF全文

T D Butt  A M Cruz  J V Bailey    W H Crawford 《The Canadian veterinary journal. La revue veterinaire canadienne》2001,42(12):936-939

The object of this investigation was to determine the outcome of limb amputation in wapiti. Medical records of 13 wapiti that underwent limb amputation were reviewed to determine age, weight, sex, injury preceding amputation, limb amputated, amputation location, length of hospital stay, complications, and outcome. Ages ranged from 3 months to 8 years and weights from 70 kg to 280 kg. All animals were female. Eleven animals sustained catastrophic long bone fractures prior to amputation. Five animals had front limb amputations and 8 had hind limb amputations. Of these animals, 1 with a front limb amputaiton and 5 with hind limb amputations survived. Postsurgical inability to stand is associated with hospitalization of > 1 day. Of the 13 wapiti reviewed, 5 with hind limb amputations have produced and reared offspring. Hind limb amputation can be considered a viable alternative to euthanasia when catastrophic orthopedic injuries occur in female wapiti.  相似文献   

离心式压缩机喘振问题分析     

唐善华  薛献忠 《油气储运》2004,23(1):36-38

当压缩机内气体的流量较低时,气体容易出现旋转脱离现象,导致压缩机不能正常工作,采取增加压缩机内部液体的流量,在出口处设置单向阀防止气体倒流等措施,可有效地防止喘振的发生,保证输气管道的正常运行.  相似文献   

Grouped, stacked rods and tapeta lucida in the retina of Japanese anchovy Engraulis japonicus     

Kamonpan Awaiwanont  Wisnu Gunarso  Munefumi Sameshima  Seiichi Hayashi  Gunzo Kawamura 《Fisheries Science》2001,67(5):804-810

ABSTRACT: Morphology of the photoreceptor cells and tapetum of the Japanese anchovy Engraulis japonicus was studied by histologically and by chemical analysis. The Japanese anchovy has a duplex retina. The cones form parallel rows consisting of alternately placed long cones and bifid cones. Both types of cones are intimately associated and form triple units that are regularly spaced along the row of cones. The rods are grouped and stacked. This fish has a retinal tapetum lucidum composed of guanine and hypoxanthine. Three structures of the tapetum lucidum were recognized: platelet, diamond and rod types. Photomechanical changes include movements of the photoreceptor cells and the retinal tapetum. The retina of the Japanese anchovy is thought to be highly sensitive and well adapted to a dim light environment.  相似文献   

Online First publication     

Springer-Verlag  The Editor-in-Chief 《Biology and Fertility of Soils》2001,33(1):1-1

  相似文献   

污水污物潜水旋流泵性能及设计方法试验研究   总被引：1，自引：0，他引：1  

沙毅  杨敏官  袁寿其  王劲松  李传君  闻建龙 《农业机械学报》2004,35(5):82-85,69

对影响潜水旋流泵性能的6个主要过流件几何参数进行了试验研究，初步掌握了旋流泵叶轮及泵体主要几何尺寸对性能影响的规律。在分析16种优秀水力模型的基础上，计算出叶轮D2及b2函数回归方程式，并用设计实例进行检验，样机效率比国内外同类产品提高3％左右。  相似文献   

压力实时监测法在管道泄漏检测中的应用   总被引：2，自引：0，他引：2  

靳春义  宋春花 《油气储运》2001,20(8):48-49

检测输油管道漏油的方法很多，介绍了通过压力实时监测确定输油管道漏油点方法，以及实际应用情况。实践证明，通过压力实时监视确定输油管道漏油点的方法在实际输油运行中是切实可行的。  相似文献   

大白菜新品种中熟6号的选育     

方淑桂  陈文辉  曾小玲 《中国蔬菜》2004,1(4):25-26

中熟 6号是由大白菜雄性不育系 98- 2 - 1和从丰抗 70中多代自交分离而选育出的自交系F - 3-2 - 3配制而成的优良一代杂种。抗霜霉病、病毒病与软腐病 ,生长期 6 0～ 6 5d(天 ) ,叶球叠抱、圆头、卵圆形。南方栽培平均单球质量 2 .0kg ,每 6 6 7m2 产量 4 0 0 0～ 5 0 0 0kg。  相似文献   

小麦条锈病流行程度趋势预测专家系统雏型     

肖长林  曾士迈 《中国农业大学学报》1990,(Z1):126-132

本文运用知识工程语言 M·1构造了一个用于小麦条锈病流行程度趋势预测的专家系统雏型。专家的知识用产生式规则来表示。知识库中的知识规则可相对独立,便于知识库的扩充和完善。  相似文献