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71.
发动机中沼气着火延迟期的计算   总被引:2,自引:0,他引:2  
沼气着火延迟期的计算是建立燃烧模型、研究沼气发动机燃烧过程的基础,本文在集总燃烧过程化学反应的基础上对火花点火发动机中沼气-空气混合气的着火延迟期进行了计算。  相似文献   
72.
本文通过对图书馆存在的委托关系进行研究,利用逆向选择与道德风险等方法试图找到一种解决这种由于信息不对称所造成的委托代理关系对图书馆工作所带来的负面影响的方法,提出改进图书馆工作的一些建议。  相似文献   
73.
豆腐渣混合苹果渣固态发酵改善纤维适口性   总被引:1,自引:2,他引:1  
为了改善豆腐渣发酵后膳食纤维的适口性,适量混合部分苹果渣,利用其糖分提高酿酒酵母的发酵效率,并对其固态发酵工艺条件进行优化。采用单因素和正交试验方法优化的较佳发酵条件为pH值为8、发酵温度22℃、豆腐渣与苹果渣质量比2∶1、酿酒酵母接种量8%、发酵时间48 h。在优化发酵条件下,豆腐渣和苹果渣混合物中粗纤维的质量分数由发酵前的107.8 mg/g下降到发酵后的64.2 mg/g,降解率为40.45%。混合苹果渣的固态发酵极大地改善了膳食纤维的适口性,可以作为健康食品原料广泛使用。  相似文献   
74.
风险投资体系以多重激励和不对称信息为特征,风险投资的三方利益主体之间存在着双重委托-代理关系,有效控制代理风险是风险投资高效运作的基本前提。本文基于信息经济学原理,分析了风险投资家与风险企业家之间代理风险的成因,并从委托人的角度讨论了风险治理的原则和投资契约的构造。  相似文献   
75.
The aetiology of claw disease in 24 dogs exhibiting only claw disease was investigated with cytologic examination of claw exudate, complete blood count (CBC), serum biochemistry panel, urinalysis, total thyroxine (tT4) concentration, antinuclear antibody (ANA) titre, bacterial culture and sensitivity testing, fungal culture, histopathology of claw biopsy samples and elimination diet. Abnormalities on the CBC, serum biochemistry panel and urinalysis were minor and nonspecific. Total T4 concentrations were within the normal laboratory reference range. Fungal cultures and ANA titres were negative in all dogs. A bacterial infection was present in approximately half of the dogs. On histological examination of claw tissue, a cell-poor or cell-rich interface onychitis was seen in all but one dog. Evidence for an adverse reaction to food was present in four dogs. One dog responded completely to antibiotic therapy. Interface onychitis seems to be a histological reaction pattern of the claw matrix in the dog with various possible underlying aetiologies. In dogs with claw disease as the only clinical sign, the recommended initial diagnostic evaluation includes cytologic examination, bacterial culture and sensitivity, claw biopsy and an elimination diet.  相似文献   
76.
氨基酸微量元素螯合物的制备检测及应用   总被引:3,自引:0,他引:3  
本文探讨了甘氨酸、蛋氨酸与铜、锌、钴的螯合物制备过程中,反应液的PH值、反应物的摩尔比以及反应时间对螯合效果的影响;测定了3种金属在最适PH范围内与两种氨基酸螯合产物的配位比,并利用毛发水解物制备了复合氨基酸微量元素螯合物,用小型网箱进行了螯合盐与无机盐的对比养鲤试验,结果表明,当氨基酸与金属反应的摩尔比较低时,易形成配位比为1:1的螯合物;当氨基酸配体的浓度大于2倍的金属离子浓度时,可形成配位比  相似文献   
77.
Statistical algorithms for detecting safety signals are beginning to be applied to Animal Health Pharmacovigilance (PV) databases. How these signal detection algorithms (SDAs) perform in an animal health PV database is the subject of this report. Statistical methods and SDAs were assessed against a set of known signals in order to identify which SDAs were most appropriate for signal detection using the Elanco Animal Health PV database. A reference set of adverse events that should signal was created for 31 products across four species. Nine SDAs based on five disproportionality statistical methods were evaluated against the reference set. The performance metrics were sensitivity, precision, specificity, accuracy, and F score. For bovine and porcine products, the Observed‐to‐Expected (O/E) SDA was the closest in terms of geometric distance to 100% sensitivity and 100% precision. For canine and feline products, the Information Component (IC) SDA was geometrically closest to 100% sensitivity and 100% precision. Principal Component Analysis confirmed that the O/E and IC SDAs were unique performers with respect to one another and other SDAs. The performance of the SDAs was dependent on the choice of the statistical method with differences seen between animal species.  相似文献   
78.
Three pot experiments were earned our to investigate the variation among geographic accessions of Orobanche crenata Forsk. in their ability to attack different stocks of Vicia faba L. Orobanche accessions were quite different in their influence on the performance of genetic lines of the host. However, host parasite relationships appeared to be dependent upon environmental conditions. The usefulness or host genotypes for differentiating between parasite accessions was rather limited. The number of Orobanche shoots per host plant does not appear 10 be a precise indicator of host tolerance although it has been frequently used for this purpose.  相似文献   
79.
80.
Adverse drug reactions to trimethoprim-sulphonamide combinations are common in many species, manifesting as gastrointestinal tract disorders, dermatopathies and blood dyscrasias. In this case series, neurological abnormalities in 4 horses being treated with trimethoprim-sulphonamide combinations at normal dosages and in one foal that received an overdose are described. The horses developed hypermetric gait, agitation and erratic behaviour. All signs resolved once medication was withdrawn, and no horse had residual deficits. No other cause for observed neurological deficits could be determined. These clinical signs appear to represent a novel adverse drug reaction to some commonly used antimicrobial combinations.  相似文献   
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