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排序方式: 共有3891条查询结果,搜索用时 15 毫秒
991.
详细地介绍了单体建筑空调机房的控制任务及远程监控系统网络,控制系统选型及配置,空调机房的设备自动控制逻辑。 相似文献
992.
直流电源系统故障分析与处理 总被引:1,自引:1,他引:0
介绍了智能高频直流电源系统的所有可能故障及其排除方法.其故障分析的方法和处理办法同样适应所有类型的直流电源系统. 相似文献
993.
A series of synthetic variations of material intrinsic properties always come with charging phenomena due to electron beam irradiation.The effects of charging on the dielectric constant will influence the charging dynamic in return.In this paper,we propose a numerical simulation for investigating the dynamic characteristics of charging effects on the dielectric constant due to electron beam irradiation.The scattering process between electrons and atoms is calculated considering elastic and inelastic collisions via the Rutherford model and the fast secondary electron model,respectively.Internal charge drift due to E-field,density gradient caused diffusion,charges trap by material defect,free electron and hole neutralization,and variation in the internal dielectric constant are considered when simulating the transport process.The dynamics of electron and hole distributions and charging states are demonstrated during E-beam irradiation.As a function of material nonlinear susceptibility and primary energy,the dynamics of charging states and dielectric constants are then presented in the charging process.It is found that the variation in the internal dielectric constant is more with respect to the depth and irradiation time.Material with a larger nonlinear susceptibility corresponds a faster charging enhancement.In addition,the effective dielectric constant and the surface potential have a linear relationship in the charging balance.Nevertheless,with shrinking charging affect range,the situation with a higher energy primary electron comes with less dielectric constant variation.The proposed numerical simulation mode of the charging process and the results presented in this study offer a comprehensive insight into the complicated charging phenomena in electron irradiation related fields. 相似文献
994.
This paper describes and discusses experimental results on the absorption of sulphur dioxide in electrified water sprays, either when the polluted gas is treated as is or when the gas is exposed to a corona source to ionize the sulphur dioxide. The experiments revealed that an electrified spray with a charge-to-mass ratio of 50 μC · kg−1 enabled the absorption rate of droplets to double, regardless of their polarities. Corona charging gave rise to an increase in the SO2 depletion rate over the scrubber wall, while negligible effects appeared on the actual droplets absorption rate. These findings suggested that faster absorption rates mostly, though not uniquely, depend on the modifications on the morphological and interfacial properties of the sprayed droplets induced by the free electric charge imposed on their surface. Conversely, the absorption rates were negligibly affected by the electrical interactions between droplets (either charged or uncharged) and the sulphur dioxide ions/radicals originating from the corona source. 相似文献
995.
结合当前国内包装型乳化炸药的工艺技术特点,对活塞泵在乳化炸药装药、输送过程中的优越性进行了分析探讨,结果表明,活塞泵明显优于传统转子泵与叶片泵; 活塞泵安全系数高、与乳化炸药生产匹配性强、不破坏乳化炸药体系的稳定性,能够广泛应用于物理敏化、化学敏化、复合敏化等多种商品乳化炸药的生产中。 相似文献
996.
997.
998.
东方1—1气田天然气组成的不均一性与幕式充注 总被引:19,自引:5,他引:14
莺歌海盆地东方11气田天然气的主要组成(烃气、CO2和N2)在侧向上和垂向上的变化很大。烃类气(生物气除外)主要来自成熟—高成熟的中新统烃源岩;无机成因CO2可能主要是气源岩进入高成熟晚期以后,其中的钙质成分热分解或与粘土矿物反应的产物;N2则为有机成因且较无机CO2生成早。天然气组成的不均一性和同位素变化表明,该气田储集层之间存在泥岩隔层,各断块之间互不连通,甚至同一断块的个别单元储集层在横向上亦局部存在非渗透带。据此,结合流体包裹体信息及烃源岩的生气演化史,认为该区地质历史时期中至少发生过4期天然气充注:第一期充注为生物气,第二期、第三期充注以CH4、N2热成因气为主,第四期充注以无机CO2为主并伴生高熟烃气。这一幕式充注过程与由于盆地深部超压释放引起的底辟活动密切相关。 相似文献
999.
《International Journal of Hydrogen Energy》2020,45(38):18995-19006
In this article, a robust optimization approach for designing an off-grid solar-powered charging station is proposed to provide electric vehicles (EVs) with electricity and hydrogen vehicles (HV) with hydrogen. A water electrolyzer (WE) is installed in the system to produce and store hydrogen, which is used by the HVs and fuel cell (FC). During the inaccessibility of the photovoltaic (PV) system to feed the EVs, the FC runs on hydrogen to regenerate electricity. Besides, in case the PV system and FC have power shortage to meet the demand of EVs, a diesel generator contributes to electricity production. There are uncertainties involved in the power profile of the PV system as well as the hydrogen and electric demands of the charging station. The novelty of this paper is to integrate robust optimization as a powerful nonstochastic framework into the mixed-integer linear programming (MILP) of the deterministic model to deal with the uncertainties. The technical and economic results prove that the construction of the charging station by considering the highs level of robustness against the negative impacts of uncertainties leads to higher capacities of the PV system and diesel generator. Consequently, the total annualized cost increases from $ 287,256 in deterministic mode to $ 326,757 in robust mode, by 13.75%. 相似文献
1000.
Identifying the Origin and Contribution of Surface Storage in TiO2(B) Nanotube Electrode by In Situ Dynamic Valence State Monitoring
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Yuxin Tang Yanyan Zhang Oleksandr I. Malyi Nicolas Bucher Huarong Xia Shibo Xi Zhiqiang Zhu Zhisheng Lv Wenlong Li Jiaqi Wei Madhavi Srinivasan Armando Borgna Markus Antonietti Yonghua Du Xiaodong Chen 《Advanced materials (Deerfield Beach, Fla.)》2018,30(33)
Fundamental insight into the surface charging mechanism of TiO2(B) nanomaterials is limited due to the complicated nature of lithiation behavior, as well as the limitations of available characterization tools that can directly probe surface charging process. Here, an in situ approach is reported to monitor the dynamic valence state of TiO2(B) nanotube electrodes, which utilizes in situ X‐ray absorption spectroscopy (XAS) to identify the origin and contribution of surface storage. A real‐time correlation is elucidated between the rate‐dependent electrode performance and dynamic Ti valence‐state change. A continuous Ti valence state change is directly observed through the whole charging/discharging process regardless of charging rates, which proves that along with the well‐known non‐faradaic reaction, the surface charging process also originates from a faradaic reaction. The quantification of these two surface storage contributions at different charging rates is further realized through in situ dynamic valence state monitoring combined with traditional cyclic voltammetry measurement. The methodology reported here can also be applied to other electrode materials for the real‐time probing of valence state change during electrochemical reactions, the quantification of the faradaic and non‐faradaic reactions, and the eventual elucidation of electrochemical surface charging mechanisms. 相似文献