两种常温固化木材胶粘剂胶接强度分析

对两种木材用常温固化胶粘剂--单宁-甲醛胶粘剂和聚氨酯胶粘剂胶接的速生杨木的静态剪切强度进行了测试与分析.研究结果表明,以速生杨I-72为被胶接对象,自制的双组分型单宁胶压缩剪切强度范围为8.08～8.92MPa,但木破率较低,要满足日本集成材JAS标准中用胶规定,需进一步研究改进.相比较而言,聚氨酯胶粘剂的胶接强度较高,其压缩剪切强度值均在9.8MPa以上,木破率在75%以上,能够满足日本集成材JAS标准中用胶的规定.     

青贮玉米育种和栽培的研究与探讨

主要对青贮玉米育种、栽培进行了浅析，并指出其发展前景，旨在推动我国青贮玉米育种研究再上一个新台阶。     

关于曲线在一点的基本三棱形的探讨

以弧长为参数,定义了曲线在一点的弗雷内标架与基本三棱形,推导出其对应量的一般参数方程.     

用线性递推关系求行列式的值

给出了用组合数学中的递推关系H_n=■α_iH_(n-i)(其中α_1,α_2,…,α_r为常数)计算具有二阶及二阶以上常系数递推关系的n阶行列式的计算方法.通过实例给出此方法的解题步骤,并验证了其可行性.     

浸水大堤填土饱和度修正意义及工程运用

饱和度指标可通过含水率换算获得；但对长期浸水的大堤而言，由于采用烘干法试验测得的试样的含水率普遍偏高，因此直接计算的饱和度值普遍偏大；根据土、水相互作用性质，分析土颗粒周围结合水分布特点，指出浸水大堤填土试样饱和度偏高的原因在于烘干试验中有部分弱结合水逸出，并且这部分弱结合水被计入到重力水中；根据经典土力学理论，建立完全饱和土的二相体系模型，对饱和度与弱结合水含量间的关系进行定量分析，并把所得的结论用于工程实践。     

Study on Proliferation and Apoptosis of EBL Cells Induced by P48 Protein of Mycoplasma bovis

The aim of this study was to investigate the effect of P48 protein on proliferation and apoptosis of embryonic bovine lung (EBL) cells.In this study,samples which co-incubated with P48 protein and EBL cells in different concentrations at different time points were collected,the proliferation rate of the cells was detected by MTT method,and the changes in the nuclear morphology of EBL cells were observed by DAPI staining method.Meanwhile,flow cytometry was used to detect the apoptosis rate of EBL cells induced by P48 protein.Real-time quantitative PCR was used to detect the changes in mRNA level of apoptotic marker genes,and Western blotting tested the Bax and Beclin-1 protein expressions.The results showed that under the condition of 72 h and 10 μg/mL of protein concentration treatment,P48 extremely significantly inhibited EBL cells proliferation (P<0.01),while 0.1 and 0.5 μg/mL protein concentration had no inhibitory effect (P>0.05).The nuclear morphology showed no significant change after protein induction for 12 h,but wrinkled and condensed at 24 h.The nucleus was fragmented,and a sprouted apoptotic body was appeared at 48 and 72 h.Apoptosis related genes expression showed no obvious increase at 2 and 12 h at mRNA level,but gradually increased at 24,48 and 72 h,and it showed a time-dependent manner.Accordingly,the expression of apoptosis marker proteins Bax and Beclin-1 significantly increased.Flow cytometry analysis showed that the apoptosis rate of EBL cells induced by P48 protein was 48.44%.In conclusion,P48 recombinant protein of Mycoplasmas bovis inhibited the proliferation of EBL cells and promoted their apoptosis,which provided reference for revealing the pathogenic mechanism of Mycoplasmas bovis.     

基于ArcIMS的江川县森林资源信息发布系统

介绍了ArcIMS的体系结构、特点及技术优势。构建了基于ArcIMS的江川县森林资源信息发布系统,提出了系统设计的思路、功能、特点,并实现了部分功能。     

黑加仑嫩枝扦插三个时期的水分管理

文章介绍了黑加仑嫩枝扦插苗生根过程中三个时期的水分管理,可供生产实践参考。