科创中国

Computer-based conceptual design for routine design has made great strides, yet non-routine design has not been given due attention, and it is still poorly automated. Considering that the function-behavior-structure(FBS) model is widely used for modeling the conceptual design process, a computer-based creativity enhanced conceptual design model(CECD) for non-routine design of mechanical systems is presented. In the model, the leaf functions in the FBS model are decomposed into and represented with fine-grain basic operation actions(BOA), and the corresponding BOA set in the function domain is then constructed. Choosing building blocks from the database, and expressing their multiple functions with BOAs, the BOA set in the structure domain is formed. Through rule-based dynamic partition of the BOA set in the function domain, many variants of regenerated functional schemes are generated. For enhancing the capability to introduce new design variables into the conceptual design process, and dig out more innovative physical structure schemes, the indirect function-structure matching strategy based on reconstructing the combined structure schemes is adopted. By adjusting the tightness of the partition rules and the granularity of the divided BOA subsets, and making full use of the main function and secondary functions of each basic structure in the process of reconstructing of the physical structures, new design variables and variants are introduced into the physical structure scheme reconstructing process, and a great number of simpler physical structure schemes to accomplish the overall function organically are figured out. The creativity enhanced conceptual design model presented has a dominant capability in introducing new deign variables in function domain and digging out simpler physical structures to accomplish the overall function, therefore it can be utilized to solve non-routine conceptual design problem.

The thermal scratch seriously affects the surface quality of the cold rolled stainless steel strip. Some researchers have carried out qualitative and theoretical studies in this field. However, there is currently a lack of research on effective forecast and control of thermal scratch defects in practical production, especially in tandem cold rolling. In order to establish precise mathematical model of oil film thickness in deformation zone, the lubrication in cold rolling process of SUS410L stainless steel strip is studied, and major factors affecting oil film thickness are also analyzed. According to the principle of statistics, mathematical model of critical oil film thickness in deformation zone for thermal scratch is built, with fitting and regression analytical method, and then based on temperature comparison method, the criterion for deciding thermal scratch defects is put forward. Storing and calling data through SQL Server 2010, a software on thermal scratch defects control is developed through Microsoft Visual Studio 2008 by MFC technique for stainless steel in tandem cold rolling, and then it is put into practical production. Statistics indicate that the hit rate of thermal scratch is as high as 92.38%, and the occurrence rate of thermal scratch is decreased by 89.13%. Owing to the application of the software, the rolling speed is increased by approximately 9.3%. The software developed provides an effective solution to the problem of thermal scratch defects in tandem cold rolling, and helps to promote products surface quality of stainless steel strips in practical production.

The current design of hydro-viscous clutch(HVC)in tracked vehicle fan transmission mainly focuses on high-speed and high power.However,the fluid torque under the influence of fluid temperature can not be predicted accurately by conventional mathematical model or experimental research.In order to validate the fluid torque of HVC by taking the viscosity-temperature characteristic of fluid into account,the test rig is designed.The outlet oil temperature is measured and fitted with different rotation speed,oil film thickness,oil flow rate,and inlet oil temperature.Meanwhile,the film torque can be obtained.Based on Navier-Stokes equations and the continuity equation,the mathematical model of fluid torque is proposed in cylindrical coordinate.Iterative method is employed to solve the equations.The radial and tangential speed distribution,radial pressure distribution and theoretical flow rate are determined and analyzed.The models of equivalent radius and fluid torque of friction pairs are introduced.The experimental and theoretical results indicate that tangential speed distribution is mainly determined by the relative rotating speed between the friction plate and the separator disc.However,the radial speed distribution and pressure distribution are dominated by pressure difference at the lower rotating speed.The oil film fills the clearance and the film torque increases with increasing rotating speed.However,when the speed reaches a certain value,the centrifugal force will play an important role on the fluid distribution.The pressure is negative at the outer radius when inlet flow rate is less than theoretical flow,so the film starts to shrink which decreases the film torque sharply.The theoretical fluid torque has good agreement with the experimental data.This research proposes a new fluid torque mathematical model which may predict the film torque under the influence of temperature more accurately.

Several typical flexible pneumatic actuators(FPA) and different mechanical models describing their behaviors have been proposed, however, it is difficult to balance compliance and load capacity in conventional designs, and these models still have limitations in predicting behavior of FPAs. A new flexible pneumatic bending joint(FPBJ) with special anisotropic rigidity structure is proposed. The FPBJ is developed as an improvement with regard to existing types of FPA, and its principal characteristic is derived from the special anisotropic rigidity structure. With this structure, the load capacity in the direction perpendicular to bending plane is strengthened. The structure of the new FPBJ is explained and a mathematical model is derived based on Euler-Bernoulli beam model and Hook's law. To obtain optimum design and usage, some key structure parameters and input-output characteristics are simulated. The simulation results reveal that the relationship between the structure parameters and FPBJ's bending angle is nonlinear. At last, according to the simulation results, the FPBJ is manufactured with optional parameters and tested. The experimental results show that the joint's statics characteristics are reflected by the mathematical model accurately when the FPBJ is deflated. The maximum relative error between simulation and experimental results is less than 6%. However, the model still has limitations. When the joint is inflated, the maximum relative error reaches 20%. This paper proposes a new flexible pneumatic bending joint which has sufficient load capacity and compliance, and the mathematical model provides theoretical guidance for the FPBJ's structure design.

甲状腺激素应答基因(thyroid hormone responsive SPOTl4,THR5P)是受甲状腺激素诱导表达的核内基因,参与脂肪合成代谢途径限速酶的转录调控,对动物脂肪生成具有重要的调控作用.为进一步研究猪SPOTl4基因所编码蛋白质的生物学功能,本实验将猪SPOTl4(GenBank登录号:JF951726)的ORF片段与表达载体pET一280ff+)进行重组,获得的重组子pET一280ff+).S14,转化大肠杆菌(Escherichiacoli)BL21(DE3)感受态细胞,重组菌经IPTG诱导,通过SDS.PAGE分析显示,目的蛋白分子量约为20.91kD,且主要以包涵体形式存在,最佳诱导条件是37℃1mmol/LIPTG诱导5h.将获得的包涵体用6xHisNi-NTA纯化柱纯化后,采用Westemblot进一步检测到了21kD目的蛋白的表达.重组质粒pET.280L(+)一S14在大肠杆菌BL21(DE3)中成功地得到了表达,不仅为SPOTl4基因生物学功能的研究,而且为进一步研究S14蛋白功能,了解脂肪代谢调控机制提供了基础资料.

针对文本中冗余的欠缺,造成在文本中隐藏信息量少而难以实现隐密信息的传输,提出了一种基于聊天表情符号的信息伪装新方法,应用于网络聊天中以增加隐蔽性.该方法简单实用、可操作性强,实验证明,该算法具有良好的不可见性和安全性,容量也较为理想,达到信息伪装的目的.

多年调节水库调节性能较高,其兴利库容对整个工程规模的确定至关重要.以贵州省麻江县上寨水库多年调节水库为例,通过对水库的径流系列进行分析,采用时历法和数理统计法对水库的兴利库容进行计算,对该水库的兴利库容计算结果进行了评价,并对多年调节水库兴利调节中采用的基础资料及计算方法进行了简要分析.

α-乳清蛋白(α-lactalbumin,α-LA)是哺乳动物乳汁中一种重要的蛋白质,富含机体必需氨基酸和支链氨基酸,其极佳的氨基酸比例、易吸收性以及功能特异性,使得α-LA在婴幼儿个体正常生长中具有重要的意义.本实验旨在构建人α-乳清蛋白真核表达载体pIRES2-ZsGreenl-opLA,将其转染至猪(Sus scrofa)的成纤维细胞,获得稳定表达人仪一LA的细胞.根据猪基因密码子偏爱性优化并合成人α-乳清蛋白基因mRNA序列opLA,并将其定向克隆入pIRES2一ZsGreenl真核表达载体,双酶切及测序方法鉴定重组载体;脂质体介导的方法将载体转染入培养的猪成纤维细胞,荧光显微镜下观察转染效果,G418抗性筛选重组细胞;RT-PCR方法检测目的基因的表达.结果表明,通过酶切以及测序鉴定得到的重组载体pIRES2一ZsGreenl-opLA构建成功;荧光显微镜下观察,转染了plRES2-ZsGreenl-opLA和pIRES2一ZsGreenl空载体的细胞均发出绿色荧光,且荧光多集中于细胞核;筛选重组细胞的最小G418浓度为400ng/μL;RT-PCR法检测到与目的基因大小一致的片段,而未转染组和转染空载体组均未检测到.本实验成功构建真核表达载体pIRES2-ZsGreenl-opLA,并获得稳定表达目的基因的猪成纤维细胞,该细胞可作为进一步研究转基因克隆猪的供体细胞.

目的:构建表达人LIM矿化蛋白-1(LIM mineralization protein-1,LMP-1)基因的腺病毒重组体,体外感染骨肉瘤(Osteosarcoma,OS)细胞系U2OS,并鉴定LMP-1基因在U2OS中的表达.方法:以K562细胞的cDNA为文库,采用PCR方法对LMP-1进行扩增,通过TA克隆与pGEM-T载体连接并DNA测序.双酶切后并将目的基因插入至腺病毒穿梭质粒pAdtrack-CMV,对腺病毒穿梭质粒pAdtrack-CMV-LMP-1行双酶切和DNA测序鉴定,并通过荧光显微镜、RT-qPCR和Western blot检测pAdtrack-CMV-LMP-1在HEK-293T细胞中的表达.线性化pAdtrack-CMV-LMP-1,在BJ5183菌内完成与骨架质粒pAdeasy-1的同源重组,构建重组腺病毒质粒Ad-LMP-1.通过脂质体介导,在HEK-293A细胞内包装出复制缺陷的重组腺病毒Ad-LMP-1,大量扩增、纯化并测定滴度.用Ad-LMP-1感染OS细胞系U2OS,通过荧光显微镜、RT-qPCR和Western blot检测LMP-1在U2OS细胞中的表达.结果:双酶切和DNA测序鉴定穿梭质粒pAdtrack-CMV-LMP-1构建成功,荧光显微镜证实转染了pAdtrack-CMV-LMP-1质粒的HEK-293T细胞内有绿色荧光蛋白表达,RT-qPCR和Western blot验证了LMP-1基因的表达量明显高于对照组.通过扩增、纯化,Ad-LMP-1滴度达到1.5*109pfu/ml.荧光显微镜下观察重组腺病毒感染的U2OS内有绿色荧光蛋白表达,RT-qPCR和Western blot检测发现重组腺病毒感染U2OS后,LMP-1的mRNA和蛋白表达量明显高于对照组.结论:成功构建了人LMP-1基因腺病毒重组体,为进一步的实验研究奠定了基础.

探讨生长分化因子-9(GDF-9)及其mRNA在高雄激素多囊卵巢综合征(PCOS)大鼠模型中的表达.方法:43只雌性sD大鼠随机分组,实验组大鼠皮下注射脱氢表雄酮建立PCOS动物模型;采用放射免疫法测定血清性激素水平,结合大鼠模型卵巢组织HE染色的病理结构改变进行模型验证;采用免疫组织化学法检测大鼠卵巢组织GDF-9表达及定位,蛋白印迹法进-步观察GDF-9表达变化;逆转录PCR法检测GDF-9mRNA表达.结果:血清性激素水平及HE染色病理结果均提示模型建立成功.免疫组织化学结果显示实验组卵泡中GDF-9表达增强,卵巢间质GDF-9表达下降,实验组和对照组间卵泡和间质灰度值差异均有统计学意义(P〈0.05).蛋白印迹检测及PCR结果提示实验组GDF-9蛋白表达下降,而GDF-9mRNA表达与对照组比较无差异.结论:GDF-9表达及分布改变可能是PCOS发生发展的重要原因.