增材制造金属反射镜的发展综述

随着光学测量与遥感领域的不断发展,折反式光学系统对重量、体积和环境适应性等需求不断提高。基于增材制造技术的金属反射镜以其便于实现优化设计、快速制造和加工工艺性好等优点,逐渐获得国内外学者的关注与研究。与传统金属反射镜相比,增材制造金属反射镜可以提高反射镜的结构刚度,同时可实现更高程度的轻量化。增材制造反射镜可以满足光学系统对环境适应性和快速性的需求。本文首先讨论了金属反射镜的评价指标;其次,综述了国内外在基于增材制造技术制备金属反射镜领域的发展现状和技术参数,从增材制造金属反射镜的基体设计与制备和基体的后处理2个方面展开论述;然后,通过分析,总结了增材制造金属反射镜的技术路线和关键技术;最后,对增材制造反射镜的应用前景提出了展望。     

Mass cultivation of various algal species and their evaluation as a potential candidate for lipid production

Microalgae have been proposed as a promising source for biodiesel production. Focusing on algal strains for biodiesel production, efforts should be made to search new strains. Experiments were carried out to investigate the effects of growth parameters (nutrients, pH, light, aeration and temperature) and the oil percentage of eight algal strains (Chlorella sp., Cladophora sp., Hydrodictylium sp., Oedogonium sp., Oscillatoria sp., Spirogyra sp., Stigeocolonium sp., Ulothrix sp.). Results show that 6.5–7.5 is the optimum pH for the growth of all algal species. Temperature showed a greater variation (25°40°C). Ulothrix sp. gave more biomass productivity and is the most suitable strain for biodiesel production due to higher oil percentage (62%). Least biomass production was observed for Stigeocolonium sp. and least oil content was obtained from Hydrodictylium sp. It was observed that among these eight algal strains for biodiesel production, Ulothrix and Chlorella are the most promising algae species.     

Advances towards Cell-Specific Gene Transfection: A Small-Molecule Approach Allows Order-of-Magnitude Selectivity

A transfection vector that can home in on tumors is reported. Whereas previous vectors that allow moderately cell selective gene transfection used larger systems, this small-molecule approach paved the way for precise structure-activity relationship optimization. For this, biotin, which mediates cell selectivity, was combined with the potent DNA-binding motif tetralysine-guanidinocarbonypyrrol via a hydrophilic linker, thus enabling SAR-based optimization. The new vector mediated biotin receptor (BR)-selective transfection of cell lines with different BR expression levels. Computer-based analyses of microscopy images revealed a preference of one order of magnitude for the BR-positive cell lines over the BR-negative controls.     

激光惯性约束聚变靶制备技术研究进展

在实验室实现聚变反应释放的能量大于点燃聚变反应所需能量的阈值是当今世界ICF研究的主要目标,实现这一目标仍需要深入研究一系列的关键物理问题。在ICF研究中,制靶能力的发展与提升至关重要,靶的质量是实验成功的核心要素之一。本文介绍了国际ICF靶制备工作近年来在新型烧蚀层材料靶丸、新型靶丸支撑技术、优化黑腔材料与构型以及减小燃料填充管直径等方面取得的一系列进展,并结合ICF物理需求,简要阐述了ICF靶的发展趋势。     

Fatigue damage behavior of a surface-mount electronic package under different cyclic applied loads

This paper studies and compares the effects of pull-pull and 3-point bending cyclic loadings on the mechanical fa- tigue damage behaviors of a solder joint in a surface-mount electronic package. The comparisons are based on experimental investigations using scanning electron microscopy （SEM） in-situ technology and nonlinear finite element modeling, respec- tively. The compared results indicate that there are different threshold levels of plastic strain for the initial damage of solder joints under two cyclic applied loads; meanwhile, fatigue crack initiation occurs at different locations, and the accumulation of equivalent plastic strain determines the trend and direction of fatigue crack propagation. In addition, simulation results of the fatigue damage process of solder joints considering a constitutive model of damage initiation criteria for ductile materials and damage evolution based on accumulating inelastic hysteresis energy are identical to the experimental results. The actual fatigue life of the solder joint is almost the same and demonstrates that the FE modeling used in this study can provide an accurate prediction of solder joint fatigue failure.     

Method development for quantitative monitoring of monoclonal antibodies in upstream cell-culture process samples with limited sample preparation – An evaluation of various capillary coatings

Monoclonal antibodies (mAbs) have become an important class of biopharmaceuticals used for the treatment of various diseases. Their quantification during the manufacturing process is important. In this work, a capillary zone electrophoresis (CZE) method was developed for the monitoring of the mAb concentration during cell-culture processes. CZE method development rules are outlined, particularly discussing various capillary coatings, such as a neutral covalent polyvinyl alcohol coating, a dynamic successive multiple ionic-polymer coating, and dynamic coatings using background electrolyte additives such as triethanolamine (T-EthA) and triethylamine. The dynamic T-EthA coating resulted in most stable electro-osmotic flows and most efficient peak shapes. The method is validated over the range 0.1–10 mg/ml, with a linear range of 0.08–1.3 mg/ml and an extended range of 1–10 mg/ml by diluting samples in the latter concentration range 10-fold in water. The intraday precision and accuracy were 2%–12% and 88%–107%, respectively, and inter-day precision and accuracy were 4%–9% and 93%–104%, respectively. The precision and accuracy of the lowest concentration level (0.08 mg/ml) were slightly worse and still well in scope for monitoring purposes. The presented method proved applicable for analysing in-process cell-culture samples from different cell-culture processes and is possibly well suited as platform method.     

化学师范生手持技术接受度与TPACK的相关性研究

以技术接受度模型(Technology Acceptance Model, TAM)与TPACK(Technological Pedagogical Content Knowledge,整合信息技术、教学法、学科内容的知识结构)理论为基础,以手持技术为技术接受度模型与TPACK中的技术对象,利用结构方程模型调查研究H大学化学师范生的手持技术接受度与TPACK的相关性。研究发现：(1)化学师范生对手持技术的行为意愿、感知易用性、主观规范正向影响TPACK的发展;(2)化学师范生对手持技术的感知有用性与自我效能正向影响行为意愿,并能通过行为意愿间接影响TPACK的发展。最后,基于研究结果,提出发挥示范引领作用、重视优质资源的整合应用等提升化学师范生手持技术TPACK的4条建议。     

环境水体中酚类EDCs前处理技术及分析方法研究进展

环境内分泌干扰物(EDCs)是指干扰生物体内保持自身平衡和调节发育过程中天然激素的合成、分泌、运输、代谢、结合、反应、消除等生物过程的外源性化学物质,这类物质的存在会干扰人类和野生动物的内分泌系统,带来生殖障碍、发育异常、免疫功能减弱等问题。EDCs,尤其是使用最为广泛的酚类EDCs,在水环境中的污染特征研究已是当前科学界和公众共同关注的热点问题之一。环境样品基质非常复杂,使得痕量酚类EDCs的分析检测难度较大。该文对近年来环境水体中酚类EDCs的分析方法进行了综述,分别对样品前处理与检测分析技术进行了介绍,其中前处理技术包括样品萃取、样品净化和样品衍生化,检测分析技术包括化学分析和仪器分析。最后对酚类分析方法进行了展望。