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51.
A novel synthetic route to 3-deoxy-3,3-difluoro-d-ribohexose 1 has been developed. Dihydroxidation of gem-difluorohomoallyl alcohol followed by several steps of protection and deprotection gave key intermediate 9. Oxidation of 1,5-diol 9 with 2 equiv. trichloroisocyanuric acid and catalytic TEMPO gave lactone 10. Reduction of 10 with DIBAL-H followed by deprotections afforded the target molecule 1. 相似文献
52.
汤洪泉 《阜阳师范学院学报(自然科学版)》1999,(3)
本文浅谈了新型建筑材料珐琅板和 PEX 管的性能应用,论述了加强新型建筑材料研究的重要性。新型材料能更好地提高建筑的审美性,简化建筑施工程序,提高劳动效率。 相似文献
53.
Sanjay Khan K. Sudhakar Mohd Hazwan Yusof Prof. Senthilarasu Sundaram 《Chemical record (New York, N.Y.)》2024,24(3):e202300308
The transition to sustainable transportation has fueled the need for innovative electric vehicle (EV) charging solutions. Building Integrated Photovoltaics (BIPV) systems have emerged as a promising technology that combines renewable energy generation with the infra-structure of buildings. This paper comprehensively reviews the BIPV system for EV charging, focusing on its technology, application, and performance. The review identifies the gaps in the existing literature, emphasizing the need for a thorough examination of BIPV systems in the context of EV charging. A detailed review of BIPV technology and its application in EV charging is presented, covering aspects such as the generation of solar cell technology, BIPV system installation, design options and influencing factors. Furthermore, the review examines the performance of BIPV systems for EV charging, focusing on energy, economic, and environmental parameters and their comparison with previous studies. Additionally, the paper explores current trends in energy management for BIPV and EV charging, highlighting the need for effective integration and recommending strategies to optimize energy utilization. Combining BIPV with EV charging provides a promising approach to power EV chargers, enhances building energy efficiency, optimizes the building space, reduces energy losses, and decreases grid dependence. Utilizing BIPV-generated electricity for EV charging provides electricity and fuel savings, offers financial incentives, and increases the market value of the building infrastructure. It significantly lowers greenhouse gas emissions associated with grid and vehicle emissions. It creates a closed-loop circular economic system where energy is produced, consumed, and stored within the building. The paper underscores the importance of effective integration between Building Integrated Photovoltaics (BIPV) and Electric Vehicle (EV) charging, emphasizing the necessity of innovative grid technologies, energy storage solutions, and demand-response energy management strategies to overcome diverse challenges. Overall, the study contributes to the knowledge of BIPV systems for EV charging by presenting practical energy management, effectiveness and sustainability implications. It serves as a valuable resource for researchers, practitioners, and policymakers working towards sustainable transportation and energy systems. 相似文献
54.
N-Allyl protected 3-O-benzyloxglutarimide 11 was synthesized as a useful variant of the chiral building block 10. This modification allowed a high-yielding deprotection of the allyl group from the lactam intermediate 14. Starting from this building block, the asymmetric syntheses of aza-sugars 6-deoxyfagomine (2), d-rhamnono-1,5-lactam (6), as well as d-deoxyrhamnojirimycin (5) have been achieved in high regio- and/or diastereo-controlled manner. 相似文献
55.
The FLEC®-SPME sampler, described in a previous paper, consists of an emission cell coupled with solid phase microextraction (SPME) for passive sampling of VOCs emitted from building materials. It represents an interesting alternative to standard dynamic sampling protocol as it is easier to implement. If standard dynamic sampling determines emission rates, passive FLEC®-SPME aims to the determination of the concentration in air at the material surface. That could be assumed provided that material/air equilibrium is reached. Thus, VOCs emission kinetics were studied for 3 different materials (pine wood panel, carpet and PVC floor) to determine equilibrium times. Then, the relevance of the method has been assessed using new materials through a 3-day emission test. Qualitative results were compared to those obtained from the standard method to check the ability of FLEC®-SPME to detect the most toxic compounds, named “VOCs of interest” and listed in the French regulation. Minor differences were observed, so this methodology seems promising, especially for field studies aiming in the identification of VOCs sources in buildings. Moreover, the concentration at the material surface combined to emission modeling could be used to predict indoor VOCs concentrations helping in indoor air quality diagnostic. 相似文献
56.
在大量测试实验和理论分析的基础上,研究电磁波在楼内公共烟道的传输问题,分析公共烟道环境的特殊性以及影响电磁波传输损耗的因素。提出一种适用于楼宇集中净化物联网系统的基于SX1278的无线传输方案。该方案采用直接序列扩频调制来提高系统的抗干扰性能,采用截断二进制指数退避算法作为重传机制来解决节点信号冲突碰撞问题。通过在基站端采用时间片轮转调度,来保证计数的同步性和实时性。集成测试和实地测试结果表明,该方案很好地解决了烟道内无线信号的稳定传输问题,且丢包率和误码率较低,系统可靠性好。 相似文献
57.
Pablo A. D. Castro Fernando J. Von Zuben 《Journal of Mathematical Modelling and Algorithms》2009,8(2):151-173
Recently, we have proposed a Multi-Objective Bayesian Artificial Immune System (MOBAIS) to deal effectively with building
blocks (high-quality partial solutions coded in the solution vector) in combinatorial multi-objective problems. By replacing
the mutation and cloning operators with a probabilistic model, more specifically a Bayesian network representing the joint
distribution of promising solutions, MOBAIS takes into account the relationships among the variables of the problem, avoiding
the disruption of already obtained high-quality partial solutions. The preliminary results have indicated that our proposal
is able to properly build the Pareto front. Motivated by this scenario, this paper better formalizes the proposal and investigates
its usefulness on more challenging problems. In addition, an important enhancement regarding the Bayesian network learning
was incorporated into the algorithm in order to speed up its execution. To conclude, we compare MOBAIS with state-of-the-art
algorithms taking into account quantitative aspects of the Pareto front found by the algorithms. MOBAIS outperforms the contenders
in terms of the quality of the obtained solutions and requires an amount of computational resource inferior or compatible
with the contenders. 相似文献
58.
59.
S.K. Tang 《Applied Acoustics》2010,71(10):947-954
The screening effect of balconies on a building façade in the case where the noise source is not parallel to the façade is studied using scale model experiment in the present study. Results show that the angle of source inclination to the façade has substantial effects on the balcony insertion loss in the presence of a traffic noise spectrum. Less amount of noise amplification is observed when the source is inclined compared to the case of parallel source in the presence of balcony ceiling reflections. Regression formulae in terms of three independent angles which determine the positions of the balcony and its ceiling relative to the noise source are developed for the prediction of balcony insertion loss. The discrepancy between measurements and predictions is within engineering tolerance. 相似文献
60.
受多种因素的影响,高职院校教师队伍的整体质量和水平远没能满足高职院校发展的实际需要,因而,几乎所有高职院校从创建开始就把教师队伍建设作为学院发展的基础性工作,投入大量的资源,努力提高教师队伍的整体素质.运用系统理论对教师队伍建设工作进行系统分析和顶层设计,是做好此项工作的必要前提. 相似文献