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81.
焊接变形光学测量技术研究 总被引:1,自引:0,他引:1
针对薄板焊接变形测量难的问题,提出了一种非接触式三维光学实时测量薄板焊接变形的新方法。首先通过2个高分辨率高速数字相机从不同观察点同时拍摄物体运动的视频图像;然后运用三维重建技术,包括共线方程、基于共面方程的像片定向、直接线性变换解法、外极线几何约束和光束平差解法等重建待测标志点的三维坐标;最后依据同名点将不同时刻薄板的变形状态关联起来,计算出待观测点的焊接变形量,并实时绘制显示出变形曲线。与传统方法相比,该方法具有不受焊接温度及强烈干扰影响和实时、高效、高精度等优点。 相似文献
82.
儒家思想对中国传统的法律文化产生深远的影响,是中国几千年治理国家的主导思想。深入研究儒家思想的治国理念及其与中国传统法律文化的关系.吸收儒家思想精华部分.必将对当代中国法治的现代化构建有着借鉴和弥补意义。 相似文献
83.
Unter Verwendung von Indiumphthalocyanin als Target wurde der Anreicherung von 114mIn durch den Szilard-Chalmers-Prozeβ untersucht. Bei Bestrahlung in der Spaltzone des Kernreaktors gelang es, spezifische Aktivitäten zu erzielen, die ohne Anreicherung nur durch sehr lange Bestrahlungszeiten erreicht werden können. Die Abhängigkeit der spezifischen Aktivität der spezifischen Aktivität von der Bestrahlungs zeit, von der Art und der Vorbehandlung der Targetverbindung, von der Dauer der Lagerung der bestrahlten Proben und von der Abtrennmethode wird angegeben. 相似文献
84.
Es werden methodische Untersuchungen zur Entwicklung eines Monte-Carlo-Programmes zur Berechnung der Tiefen-verteilung der primären Ionisationen auf der Grundlage der Vielfachstreutheorie von Molière beschrieben. Anhand aus-gewählter Zwei-Element-Targets wird die Leistungsfähigkeit von drei Varianten eines entsprechenden Elektronentrans-portmodells untersucht. Unter Benutzung der entwickelten Elektronentransportmodelle werden für die Elektronenstrahl-mikroanalyse interessierende Größen, wie Rückstreukoeffizient, Rückstreufaktor und Absorptionskorrektion, berechnet. 相似文献
85.
J. Miller 《Isotopes in environmental and health studies》2013,49(2):63-65
A substoichiometic analytical method of high sensitivity combined with adsorptive sampling has been worked out for the determination of traces of silver in palladium making use of the selective deposition of microquantities of silver from aqueous solutions of palladium salts on cathodically polarized platioum surfaces. The stability and reporducibility of the saturation values of deposited silver are practially independent of the content and concentration of silver and palladium in the solution. The sensitivity proved to be 0.01 ppm, the accuracy ± 30 per cent. 相似文献
86.
Abstract The range and energy-loss of 16.34 MeV/u 238U in Kapton-polyamide plastic have been measured by the nuclear track technique. The experimental ranges are compared with two sets of theoretical values. It has been observed that ranges obtained from the computer code ‘DEDXT’ are found to be 5–8% lower as compared to measured ones whereas those from Northcliffe and Schilling are about 10–15% overestimated above 8 MeV/u. 相似文献
87.
We consider a general optimal switching problem for a controlled diffusion and show that its value coincides with the value of a well-suited stochastic target problem associated to a diffusion with jumps. The proof consists in showing that the Hamilton–Jacobi–Bellman equations of both problems are the same and in proving a comparison principle for this equation. This provides a new family of lower bounds for the optimal switching problem, which can be computed by Monte-Carlo methods. This result has also a nice economical interpretation in terms of a firm's valuation. 相似文献
88.
Xiaoding Lou 《中国化学快报》2019,30(9):1557-1564
The complexity of biological samples determines that the detection of a single biomolecule is unable to satisfy actual needs. Moreover, the “false positives” results caused by a single biomolecule detections easily leads to erroneous clinical diagnosis and treatment. Thus, it is important for the homogenous quantification of multiple biomolecules in not only basic research but also practical application. As a consequent, a large number of literatures have been exploited to monitor multiple biomolecules in homogenous solution, enabling facilitating the development of the disease diagnosis, treatment as well as drug discovery. One-dimensional nanomaterials and two-dimensional nanomaterials have special physical and chemical properties, such as good electrochemical properties, stable structure, large specific surface area, and biocompatibility, which are widely used in electrochemical and fluorescent detection of biomolecules. This tutorial review highlights the recent development for the detection of multiple biomolecules by using nanomaterials including one-dimensional materials (1DMs) as well as two-dimensional materials (2DMs). 相似文献
89.
Ziyu Ning Baoyu Tan Bo Chen Dzi Shing Aaron Lau Tak Man Wong Tianhao Sun Songlin Peng Zhaoyang Li William Weijia Lu 《Macromolecular bioscience》2019,19(6)
Side‐effects from allograft, limited bone stock, and site morbidity from autograft are the major challenges to traditional bone defect treatments. With the advance of tissue engineering, hydrogel injection therapy is introduced as an alternative treatment. Therapeutic drugs and growth factors can be carried by hydrogels and delivered to patients. Abaloparatide, as an analog of human recombinant parathyroid hormone protein (PTHrp) and an alternative to teriparatide, has been considered as a drug for treating postmenopausal osteoporosis since 2017. Since only limited cases of receiving abaloparatide with polymeric scaffolds have been reported, the effects of abaloparatide on pre‐osteoblast MC3T3‐E1 are investigated in this study. It is found that in vitro abaloparatide treatment can promote pre‐osteoblast MC3T3‐E1 cells’ viability, differentiation, and mineralization significantly. For the drug delivery system, 3D porous structure of the methacrylated gelatin (GelMA) hydrogel is found effective for prolonging the release of abaloparatide (more than 10 days). Therefore, injectable photo‐crosslinked GelMA hydrogel is used in this study to prolong the release of abaloparatide and to promote healing of defected bones in rats. Overall, data collected in this study show no contradiction and imply that Abaloparatide‐loaded GelMA hydrogel is effective in stimulating bone regeneration. 相似文献
90.
Kamol Dey Silvia Agnelli Federica Re Domenico Russo Gina Lisignoli Cristina Manferdini Simona Bernardi Elena Gabusi Luciana Sartore 《Macromolecular bioscience》2019,19(8)
Rational design and development of tailorable simple synthesis process remains a centerpiece of investigational efforts toward engineering advanced hydrogels. In this study, a green and scalable synthesis approach is developed to formulate a set of gelatin‐based macroporous hybrid hydrogels. This approach consists of four sequential steps starting from liquid‐phase pre‐crosslinking/grafting, unidirectional freezing, freeze‐drying, and finally post‐curing process. The chemical crosslinking mainly involves between epoxy groups of functionalized polyethylene glycol and functional groups of gelatin both in liquid and solid state. Importantly, this approach allows to accommodate different polymers, chitosan or hydroxyethyl cellulose, under identical benign condition. Structural and mechanical anisotropy can be tuned by the selection of polymer constituents. Overall, all hydrogels show suitable structural stability, good swellability, high porosity and pore interconnectivity, and maintenance of mechanical integrity during 3‐week‐long hydrolytic degradation. Under compression, hydrogels exhibit robust mechanical properties with nonlinear elasticity and stress‐relaxation behavior and show no sign of mechanical failure under repeated compression at 50% deformation. Biological experiment with human bone marrow mesenchymal stromal cells (hMSCs) reveals that hydrogels are biocompatible, and their physicomechanical properties are suitable to support cells growth, and osteogenic/chondrogenic differentiation, demonstrating their potential application for bone and cartilage regenerative medicine toward clinically relevant endpoints. 相似文献