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1.
The National Natural Science Foundation of China (NSFC) is a vital government agency supporting basic research and people to create knowledge and meet major national needs, where a rigorous and objective merit-based peer review mechanism is the key to funding the most promising research proposals. This invited comment overviews some recent attempts aimed at bettering the academic evaluation environment at the Department of Chemical Science in 2019, through measures such as grouped panel committee meetings, standardized panel committee meeting procedures, and review process refinement to improve the project review at panel committee meeting levels. 相似文献
2.
《Operations Research Letters》2019,47(5):417-420
We analyse the point availability of Gaver’s parallel system supervised by a safety device. For safety reasons, no unit is allowed to operate without supervision. The entire system is attended by two heterogeneous repairmen. Our methodology is based on the theory of sectionally holomorphic functions combined with the notion of dual transforms. As an application we consider Coxian repair time distributions. 相似文献
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Aster Manyazewal Mola Siraye Esubalew Debebe Menbere Leul Mekonnen 《Electroanalysis》2023,35(3):e202200045
Herein, Ag nanoparticles (NPs) modified MoS2 (Ag−MoS2) was applied to the surface of glassy carbon (GC) to produce a robust electrochemical sensor for the detection of thiabendazole, a common antifungal in the post-harvesting of fruits. Cyclic voltammetry studies confirmed thiabendazole exhibited an irreversible, diffusion-controlled process on Ag−MoS2 with a two-fold increase in peak current than the pristine MoS2. A square wave voltammetry was used for the detection of TBZ. The developed sensor exhibited a linear range between 1–10 μM with LOD down to 0.1 μM (S/N>3). Analysis of TBZ in mango and banana matrices gave a recovery of 91.6–100.4 % indicating the suitability of the sensor for food safety monitoring. 相似文献
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上池西外坡岩体稳定是十三陵抽水蓄能电站主要的地质工程问题之一,由于受到倾向池外的数条缓倾角断层以及不良的岩体结构控制,存在着滑动位移、变形失稳的可能性,电站的安全运行受到潜在的威胁。因此对西外坡岩体进行稳定分析,并进行补强处理是必要的。 相似文献
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Safety and comfort analysis of a 3-D vehicle model with optimal non-linear active seat suspension 总被引:1,自引:0,他引:1
A generalized nonlinear model is formulated for the dynamic analysis of suspension seats with passive, semi-active and active dampers. The model incorporates coulomb friction due to suspension linkages and bushings, forces arising from interactions with the elastic limit stops, a linear suspension spring and nonlinear damping force for passive, semi-active and active dampers, while the contribution due to biodynamics of the human operator is considered to be negligible. The semi-active and active dampers are characterized by force generators in accordance with the control laws based upon suspension mass velocity. Two different suspension seats are experimentally assessed in the laboratory under sinusoidal and random excitations arising from an urban bus, and the measured data is used to demonstrate the validity of the proposed generalized model. The results showed reasonably good agreement between the model results and the measured data. Optimal model parameters are selected using the sequential unconstrained minimization technique with an objective to minimize the acceleration due to vibration transmitted to the occupant mass. The comfort and safety performance characteristics of the optimal suspension seat with semi-active and active dampers are evaluated under both the sinusoidal and random excitations based on the guidelines provided by ISO-2631. From these results, it is concluded that the comfort performance of a suspension seat with semi-active and active dampers can be considerably enhanced by 20–30%. 相似文献
8.
J. Burgain J. Scher G. Francius F. Borges M. Corgneau A.M. Revol-Junelles C. Cailliez-Grimal C. Gaiani 《Advances in colloid and interface science》2014
This review gives an overview of the importance of interactions occurring in dairy matrices between Lactic Acid Bacteria and milk components. Dairy products are important sources of biological active compounds of particular relevance to human health. These compounds include immunoglobulins, whey proteins and peptides, polar lipids, and lactic acid bacteria including probiotics. A better understanding of interactions between bioactive components and their delivery matrix may successfully improve their transport to their target site of action. Pioneering research on probiotic lactic acid bacteria has mainly focused on their host effects. However, very little is known about their interaction with dairy ingredients. Such knowledge could contribute to designing new and more efficient dairy food, and to better understand relationships between milk constituents. The purpose of this review is first to provide an overview of the current knowledge about the biomolecules produced on bacterial surface and the composition of the dairy matter. In order to understand how bacteria interact with dairy molecules, adhesion mechanisms are subsequently reviewed with a special focus on the environmental conditions affecting bacterial adhesion. Methods dedicated to investigate the bacterial surface and to decipher interactions between bacteria and abiotic dairy components are also detailed. Finally, relevant industrial implications of these interactions are presented and discussed. 相似文献
9.
针对一线教师的课例研究成果难以分享和传播的困境,分析了当前课例论文写作中存在的问题:缺乏教学目标、重教学设计而轻教学实践、教学反思不足、文献查阅不够、教学理论与教学实践脱节等。提出了提升课例论文质量的写作框架和内容要求,其容易被一线教师接受,注重继承性和发展性,强调教学实践数据的呈现,强调可复制性和可操作性。 相似文献
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This work investigated the effect of infusion of a self-made ultrasound contrast agent with long persistence (named ZHIFUXIAN) on rat right ventricular pressure and made a preliminary evaluation on the relative safety of the novel microbubbles. Normal saline, SonoVue and ZHIFUXIAN were injected through caudal vein at the total volume of 0.5 ml for each injection. The right ventricular systolic pressure (RVSP) and end-diastolic pressure (RVEDP) were monitored and the changes of the pressure were compared with baseline readings. RVSP increased when saline, SonoVue or ZHIFUXIAN were injected, the greatest change being after SonoVue (about 2 mm Hg), but there was no statistical significance compared with baseline (P > 0.05). There was no significant difference in RVSP between saline, SonoVue and ZHIFUXIAN at any time point. Also, there was no significant difference in RVEDP between groups at each time point and between different time points in each group. The results indicate that the self-made microbubbles effect on right ventricular hemodynamics is equivalent to that of normal saline at the same volume needed for effective enhanced imaging, demonstrating that it does not produce changes in right ventricular blood pressure under the study conditions. Pathological examination also showed it had no obvious influence on lung, liver and kidney. 相似文献