高速动能弹侵彻硬目标加速度测试技术研究

通过理论分析、计算机模拟和现场实测,研究了弹体高速侵彻硬目标时,弹体中应力波传播对弹体实测加速度的影响规律;采用不同密度、不同孔径的泡沫铝材料对电路模块进行保护。利用自主研制的弹载高g值加速度存储测试仪器,现场测取了弹体侵彻混凝土靶过程中的加速度,并分析了测试数据的有效性。     

口蹄疫病毒二价DNA疫苗的构建及实验免疫研究

通过PCR方法从本室已构建的克隆载体pGEMT-P1-2A获得O型口蹄疫病毒主要保护性抗原VP1基因,以基因突变获得A型VP1基因。将这两种血清型的VP1基因串联后连接到真核表达载体PVAX1 PCMV启动子下游,构建成口蹄疫二价核酸疫苗pVAX1-OA。经Western blot和IFA检测,目的蛋白在HeLa细胞中获得正确表达。动物实验表明,免疫小鼠T淋巴细胞明显增殖,特异性CTL杀伤活性较对照组显著提高;血清抗体能分别与O型和A型抗原反应,抗体效价均高于空白对照组,但较灭活苗低。     

恶性疟原虫DNA疫苗免疫效果的评估

以霍乱毒素Ｂ亚基（ＣＴＢ）为载体,由其基因构建了含有不同时期不同抗原表位的恶性疟原虫的融合基因ＣＴＢ￣ＡＷＴＥ和ＣＴＢ￣ＮＡＮＰ,前者除含有恶性疟原虫裂殖子表面主要抗原表位杂合多肽基因ＳＰｆ６６外,还含有很强的Ｔ辅助细胞表位ＣＳＴ３和Ｔｃ细胞表位,后者含有子孢子期的Ｂ、Ｔｈ细胞表位。将纯化的质粒免疫Ｂａｌｂ／ｃ纯系小鼠,３次免疫后诱导机体产生了体液免疫和细胞免疫,免疫的小鼠进行疟原虫子孢子攻击实验     

脂质体对牙鲆淋巴囊肿病毒核酸疫苗免疫活性的影响

将淋巴囊肿病毒核酸疫苗pEGFP-N2-LCDV0.6kb用脂质体梭华-SoftastTM包裹后肌肉注射入牙鲆体内,通过测定牙鲆外周血、肠、脾脏和前肾的淋巴细胞增殖反应、呼吸爆发活性以及抗体产生水平,评价脂质体对pEGFP-N2-LCDV0.6kb免疫活性的影响.结果表明,脂质体可显著增强该核酸疫苗的免疫活性和提高保护率,可作为一种有应用前景的核酸疫苗佐剂.     

联用抗口蹄疫病毒重组多肽及DNA疫苗诱发豚鼠产生特异免疫应答

选择一株O型口蹄病毒（FMDV）外壳蛋白VPI中21－40位及141－160位氨基酸残基两个抗原表位,组成串联结构141－160（20AA）－21－40（20AA）－141－160（20AA）,并与大肠杆菌β－半乳糖苷酶相连,在大肠杆菌中表达了此融合蛋白。同时将编码此融合蛋白的基因克隆进真核表达载体中,构建成重组表达质粒pCDM8FZ1。将pCDM8FZ1DNA与融合蛋白混合,免疫豚鼠一次,观察豚鼠产生免疫应答情况。结果显示,豚鼠可产生抗FMDV中和抗体及特异性T细胞增殖反应,部分豚鼠能抵抗FMDV的攻击,保护率为50％,证明将DNA疫苗与重组多肽疫苗结合起来作一次免疫,是可望用于预防FMDV感染的新途径,值得进一步探索。     

Effect of Difference in Acceleration and Velocity Change on Product Damage Due to Repetitive Shock

To investigate the influence of different combinations of peak acceleration and velocity change on repetitive‐shock‐induced damages leading to cumulative fatigue in products, we performed drop tests of products packaged similar to those in actual transportation, from several different drop heights and with two kinds of cushioning materials. The damage boundary curves (DBCs), corresponding to the degree of damage per shock, were prepared to investigate the possibility of DBC application for the evaluation of repetitive‐shock‐induced damage. The drop test showed erroneous results, when predicting repetitive‐shock‐induced damage, if based only on the relationship between peak acceleration and the degree of damage per shock, as have been carried out in previously reported studies. In our study, the DBCs for a specific degree of damage per shock were prepared, although the ranges of the peak acceleration and velocity change were limited. Preparation of DBC corresponding to the degree of damage per shock, as determined from the peak acceleration and velocity change beforehand, may increase the accuracy of predicting repetitive‐shock‐induced damage to products from cumulative fatigue. Copyright © 2013 John Wiley & Sons, Ltd.     

Genetic Algorithms Applied to Li+ Ions Contained in Carbon Nanotubes: An Investigation Using Particle Swarm Optimization and Differential Evolution Along with Molecular Dynamics

Empirical potentials based upon two and three body interactions were applied to the Li⁺-C system, assuming the Li⁺ ions to be distributed inside high-symmetry, single walled carbon nanotubes of different chirality. Structural optimizations for various assemblages were conducted using evolutionary and genetic algorithms, where differential evolution and particle swarm optimization techniques worked satisfactorily. The results were compared with the outcome of some rigorous molecular dynamics simulations. The potential for using the carbon nanotubes in the negative electrode of lithium ion batteries was also critically examined.     

Influence of Particle Size on the Distributions of Liposomes to Atherosclerotic Lesions in Mice

ABSTRACT

In order to confirm the efficacy of liposomes as a drug carrier for atherosclerotic therapy, the influence of particle size on the distribution of liposomes to atherosclerotic lesions in mice was investigated. In brief, liposomes of three different particle sizes (500, 200, and 70 nm) were prepared, and the uptake of liposomes by the macrophages and foam cells in vitro and the biodistributions of liposomes administered intravenously to atherogenic mice in vivo were examined. The uptake by the macrophages and foam cells increased with the increase in particle size. Although the elimination rate from the blood circulation and the hepatic and splenic distribution increased with the increase in particle size in atherogenic mice, the aortic distribution was independent of the particle size. The aortic distribution of 200 nm liposomes was the highest in comparison with the other sizes. Surprisingly, the aortic distribution of liposomes in vivo did not correspond with the uptake by macrophages and foam cells in vitro. These results suggest that there is an optimal size for the distribution of liposomes to atherosclerotic lesions.     

Optimization of Composite Foam Concept for Protective Helmets to Mitigate Rotational Acceleration of the Head in Oblique Impacts: A Parametric Study

Rotational acceleration of the head is known to be the cause of traumatic brain injuries. It was hypothesized that by introducing anisotropy in a foam liner in head protection applications, for example, protective helmets, rotational acceleration transmitted to the head can be further mitigated. Therefore, composite foam with a cylinder/matrix configuration with anisotropy at “macro level” is proposed as a smart structural solution to replace single layer foam headliners of the same weight and thickness. In this paper, a parametric study on the cylinder/matrix configuration is performed and the results are compared with these of single layer expanded polystyrene foam. The structure is subsequently optimized for the best performance in mitigation of rotational acceleration and velocity. Oblique impact results show that the parameters such as the number of cylinders in a given structure, and the compliance of the matrix foam significantly affect the extent of rotational acceleration and velocity mitigation. Optimized composite foam configurations are subsequently proposed and they demonstrate a mitigation of rotational acceleration and velocity up to 44 and 19%, respectively. Moreover, relevant global head injury criteria such as HIC (Head Injury Criterion), RIC (Rotational Injury Criterion), HIP_max (Head Impact Power), GAMBIT (Generalised Acceleration Model for Brain Injury Threshold), and BrIC (Brain Injury Criterion) demonstrated reduction up to 27, 67, 31, 26, and 19%, respectively.

     

航空发动机用双性能盘的制造技术研究进展

介绍了航空发动机用钛合金、高温合金双性能盘的制造技术研究进展。对采用不同工艺制造的双性能盘的力学性能进行了比较，并且提出了双合金一双性能盘制造中存在的主要问题是界面问题，为了解决此问题，很有必要进行双合金界面增强工艺及其增强机理的研究。