陆地棉品种间杂种F_2代优势研究及经济农艺性状的通径分析

用７个Ｆ１代具高竞争优势的陆地棉品种间杂种Ｆ＿２代和高产、优质、多抗的品种鄂棉１５（对照）为材料，研究了Ｆ＿２代及皮棉产量等经济性状的竞争优势，又对它们与株高等在艺性状进行了通径分析。结果表明：正确选配亲本，能将高产、优质、早熟综合于一体，多代利用陆地棉品种间杂种。３８４×３６１Ｆ＿２，鄂荆１号（３２４７）×３６１Ｆ２显著优于对照，分别增产１５．４９％、１２．１６％，且纤维长度、早熟性与对照相近，在生产上有很大的利用价值。决定Ｆ＿２代皮棉产量主要是单株铃数、衣分以及它们之间的互作。同一农艺性状对不同经济性状影响程度很不相同，每个经济性状一般都受１～３个主要农艺性状和它们之间，或它们与其他农艺性状互作所制约。在湖北生态条件下，高产、优质、早熟的陆地棉品种间杂种Ｆ＿２代应具备棉抹较高，果位适中而果高偏低，纵横比较大，果枝夹角较小及主茎节距较大等农艺性状     

小麦品种贵农21,贵农22抗病性研究

采用温室苗期测定和成株期人工诱发接种鉴定方法研究了簇毛麦——硬粒小麦杂种后代贵农21、22的抗病性。苗期抗性测定表明,贵农21、22对国外15个小麦条锈菌生理小种表现为免疫至近免疫反应,仅对具有毒性基因Yr10的菌系82E16表现出中度感病,对供试的国内14个主要条锈菌菌系呈观免疫至近免疫反应。田间成株期抗性试验结果显示,贵农21、22对小麦条锈病、白粉病免疫,高抗秆锈病,中抗叶锈病。小麦品种贵农21、22可作为抗病资源和生产品种加以推广应用。     

水稻条纹叶枯病(Rice stripe)暴发原因及其防治对策

水稻条纹叶枯病自20世纪90年代末以来在江苏全省大面积发生，现已成为江苏省水稻生产上发生最为严重的病害之一。分析其暴发原因：灰飞虱虫量和带毒率高；耕作栽培制度有利于发病；水稻品种不抗病等。通过调查试验明确了：利用锐劲特等药剂进行稻种处理；适当推迟水稻播栽期；选用抗耐病品种等措施的主要防治对策。     

Numerical Simulation of Flow field and Temperature field in Combustion Chamber Widened Suddenly

The flowfield and temperature field are numerically Simulated by the mathematical model of the fluid flow and heat transfer in circular combustion chamber widened suddenly. The distributions and influence factors of the flow field and temperature field are studied in it. The results have the guiding significance for the design of combustion chamber. The mathematical models can serve as the quantitative analysis methods for design.     

EXPERIMENTAL RESEARCH ON VISCOELASTICITY OF HUMAN BLOOD- WITH REFERENCE TO THE EFFECT OF CELL HEMOTOCRIT

This paper describes a part of the experiments concerning the viscoelasticity of human blood, which are based upon the theories lead by the authors. The data from the experiments are compared with those in the literatures. The effect of cell hematocrit on viscoelasticity is especially discussed and a new viscoelasticity index is defined to eliminate this effect.     

EFFECT OF MICRO-GALLIUM ON THE INTERGRANULAR SEGREGATINN OF PHOSPHORUS IN CARBON STEELS

The effect of small amounts of gallium on the intergranular segregation of phosphorus in carbon steels is discussed, with the help of the impact test, fracture morphology and micro-structure analyses, combined with composition analysis on the fracture surfaces by Auger electronspectrometer. The results show that gallium in the steel with a content of gallium more than ten thou-sandth can suppress, to some extent, the intergranular segregation of phosphorus and retard the tempering process. As a result, the temper embrittlement of the steel disappears and the embrittlement transition temperature declines.     

The Stability of Quaternion Metrices and Their Judging Criteria

Some conceptions of stable quaternion matrices and some judging criteria are given.The Robrach theorem,Taussky theorem,Ostrowski Schneider theorem and Gerschgorin theorem are generalized to quaternion field.The conclusion about two quaternion matrices,i.e.,inferior positive matrices are unstable,interior negative matrices are stable and some other results are pointed out.