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1.
5G系统将移动通信服务从移动电话、移动宽带和大规模机器通信扩展到新的应用领域,即所谓对通信服务有特殊要求的垂直领域。对使能未来工厂的5G能力进行了全面的分析总结,包括弹性网络架构、灵活频谱、超可靠低时延通信、时间敏感网络、安全和定位,而弹性网络架构又包括对网络切片、非公共网络、5G局域网和边缘计算的支持。希望从广度到深度,对相关的理论及技术应用做透彻、全面的梳理,对其挑战做清晰的总结,从而为相关研究和工程技术人员提供借鉴。 相似文献
2.
Dr. Laurent David Dr. Mark Wenlock Dr. Patrick Barton Dr. Andreas Ritzén 《ChemMedChem》2021,16(17):2669-2685
Chameleonic properties, i. e., the capacity of a molecule to hide polarity in non-polar environments and expose it in water, help achieving sufficient permeability and solubility for drug molecules with high MW. We present models of experimental measures of polarity for a set of 24 FDA approved drugs (MW 405-1113) and one PROTAC (MW 1034). Conformational ensembles in aqueous and non-polar environments were generated using molecular dynamics. A linear regression model that predicts chromatographic apparent polarity (EPSA) with a mean unsigned error of 10 Å2 was derived based on separate terms for donor, acceptor, and total molecular SASA. A good correlation (R2=0.92) with an experimental measure of hydrogen bond donor potential, Δlog Poct-tol, was found for the mean hydrogen bond donor SASA of the conformational ensemble scaled with Abraham's A hydrogen bond acidity. Two quantitative measures of chameleonic behaviour, the chameleonic efficiency indices, are introduced. We envision that the methods presented herein will be useful to triage designed molecules and prioritize those with the best chance of achieving acceptable permeability and solubility. 相似文献
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《Advanced Powder Technology》2022,33(8):103602
To operate a bag filter continuously, pulse-jet cleaning of dust particles from the filter medium is commonly required, and the pulse-jet pressure significantly affects the filter performance. In this study, the accumulation structure of residual dust particles inside and on the surface of a filter medium at different pulse-jet pressures was investigated by constructing a simple model, and the influence of the dust structure on the filter performance was clarified. Using a simple model, we determined the effective ratio of filtration area β, which represents the ratio of the filterable area to the total filtration area, the true resistance coefficient due to the primary dust layer ζp’ thinly deposited on the filter surface, and the true resistance coefficient inside the filter media itself ζf’. The effective ratio of filtration area β decreased with operation time for all pulse-jet pressures; however, it maintained a high value when the pulse-jet pressure was high. The validity of β analyzed by the model was verified using two different methods, and the results showed good agreement, indicating that the model is effective in identifying real conditions. The true resistance coefficient due to the primary dust layer ζp’ decreased as the pulse-jet pressure increased; however, the true resistance coefficient inside the filter media itself ζf’ was the highest at 0.5 MPa. In addition, the dust collection efficiency was different at each pulse-jet pressure, which was considered to be caused by the difference in the dust particle accumulation structure. 相似文献
6.
Ahmad Reza Abbasian Alireza Mahvary Shahram Alirezaei 《Ceramics International》2021,47(17):23794-23802
The effects of three types of salt including NaF, KCl, and NaCl on the properties of NiFe2O4 nanoparticles using salt-assisted solution combustion synthesis (SSCS) have been investigated. The synthesized powders were evaluated by SEM, TEM, FTIR, XRD, and VSM analysis. Also, the specific surface area (SSA), as well as size distribution and volume of the porosities of NiFe2O4 powders were determined by the BET apparatus. The visual observations showed that the intensity and time of combustion synthesis of nanoparticles have been severely influenced by the type of salt. The highest crystallinity was observed in the synthesized powder using NaCl. The SSA has also been correlated completely to the type of salt. The quantities of SSA was achieved about 91.62, 64.88, and 47.22 m2g-1 for the powders synthesized by KCl, NaCl, and NaF respectively. Although the magnetic hysteresis loops showed the soft ferromagnetic behavior of the NiFe2O4 nanoparticles in all conditions, KCl salt could produce the particles with the least coercivity and remanent magnetization. Based on the present study, the salt type is a key parameter in the SSCS process for the preparation of spinel ferrites. Thermodynamic evaluation also showed that the melting point and heat capacity are important parameters for the proper selection of the salt. 相似文献
7.
《Ceramics International》2022,48(15):21951-21960
A high surface area is one of desired properties for yttria-zirconia (Y2O3–ZrO2) ceramic materials given their catalytic applications. The objective of this study is to develop high-surface-area Y2O3–ZrO2 materials by silicon (Si) modification and investigate the role of Si. Si-modified yttrium-zirconium hydroxides were prepared via a one-step precipitation process and calcined at 800 or 950 °C to form Si-modified Y2O3–ZrO2 (denoted as SiO2–Y2O3–ZrO2) materials containing 0-20 wt% Si as SiO2. These hydroxides or materials were characterized by 29Si NMR, XPS, TG-DSC, XRD, UV Raman, TEM, and N2 physisorption measurements. Si species uniformly distributed in the hydroxides tended to be enriched on the material surface at high temperatures. These Si species dominated by the silicates blocked the migration of Y and Zr atoms, which resisted the crystallite growth of Y2O3–ZrO2 components and reduced their crystallite size. Therefore, the SiO2–Y2O3–ZrO2 possessed a surface area of 59-112 m2/g after calcination at 950 °C for 9 h, which was significantly higher than that of the Y2O3–ZrO2 (23 m2/g). This study may stimulate ideas for developing high-surface-area crystalline ceramic materials calcined at high temperatures. 相似文献
8.
Tadeusz Zając Agnieszka Klimek-Kopyra Ryszard Mazurek Andrzej Oleksy Jacek Strojny 《Journal of Natural Fibers》2020,17(8):1199-1211
ABSTRACT Nine sowing densities of linseed were compared in a two-year experiment. Self-regulation of the density of a linseed stand resulted in a differentiated branching of the plants. The number of capsules on a linseed shoot, as well as seeds in the capsule, and the number of seeds from the shoot were highly varied from year to year, and there is even a stronger differentiation in the weight of 1000 seeds. Linear relationships were noted between the mass of seeds from the linseed plant and the number of capsules. The yield of linseed was affected by both factors. An increasing sowing rate reduced the seed yield from the shoot and the plant. At lower seeding rates, the lateral shoots contributed in the seeds yield of the plant to a higher degree compared to the main ones. 相似文献
9.
2002年12月国务院批复了《南水北调工程总体规划》,明确中线工程分两期建设。目前,一期工程已经通水。近年来,随着社会经济的快速发展,受水区的人口、生产规模、节水水平、人们对环境的要求都发生了变化,因此有必要根据新的情况对受水区的用水需求重新预测。分析了城市化发展和城镇用水变化的新形势,依据流域、区域水资源规划成果,提出了中线二期工程受水区需调水量,并与《南水北调中线工程规划》提出的二期需调水量进行对比,以供各方参考。 相似文献
10.
陈四楼矿计划实施沿空留巷的2802运输巷,断层较多,直接顶厚度较大,巷道矿压显现较为明显。针对顶板下沉、两帮外鼓、顶板淋水较大、巷道顶板受压破碎、金属网锈蚀严重、压脱锚杆较多、两帮位移较大等现象,提出在高应力区采用矿压监测的方法,通过对巷道变形现状进行的监测分析,对巷道破坏变形程度有了清晰的认识,对造成巷道破坏变形原因和影响因素有了详细的分析,根据注浆加固可改善围岩结构,提高围岩承载能力及锚杆、锚索锚固性能,是一种较为有效的围岩控制措施,确定了需要采用注浆加固的方式对进行巷道围岩破坏变形治理,并根据现场实际情况对注浆材料的性能提出了要求。 相似文献