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81.
针对当前市场上销售的普通马克杯功能单一,带有电动搅拌功能的马克杯搅拌不均匀,能源损耗的情况,设计了一种基于温差发电的自动搅拌马克杯。采用温差发电作为供电来源,实现全自动搅拌,杯内温度可实时监测。设置杯内饮料的保温温度,具有操作人性化,界面友好,能源合理应用的特点。 相似文献
82.
王丽七 《兵器材料科学与工程》2012,35(6):78-81
采用机械合金化-电场激活压力辅助合成(MA-FAPAS)技术,快速合成Sc,Sb掺杂的Mg2Si基热电材料,并对其进行电性能的测试与分析。结果表明:掺杂摩尔分数为0.47%Sb的Mg2Si试样在测试温度范围内,电导率和Seebeck系数均优于未掺杂试样,其平均电功率因子约为后者的2.2~2.3倍;电导率比采用熔融-热压法制备的同类试样有所提高;在低温阶段,掺杂摩尔分数为0.43%Sc的Mg2Si试样Seebeck系数约为307 K,达未掺杂试样的2.03倍;电功率因子在温度低于550 K时高于未掺杂试样,最大值与Sb掺杂试样相当。 相似文献
83.
Cristina Cornaro Simona Bartocci Davide Musella Cecilia Strati Alessandro Lanuti Simone Mastroianni Stefano Penna Andrea Guidobaldi Fabrizio Giordano Eleonora Petrolati Thomas M. Brown Andrea Reale Aldo Di Carlo 《Progress in Photovoltaics: Research and Applications》2015,23(2):215-225
New generation photovoltaic (PV) devices such as polymer and dye sensitized solar cells (DSC) have now reached a more mature stage of development, and among their various applications, building integrated PVs seems to have the most promising future, especially for DSC devices. This new generation technology has attracted an increasing interest because of its low cost due to the use of cheap printable materials and simple manufacturing techniques, easy production, and relatively high efficiency. As for the more consolidated PV technologies, DSCs need to be tested in real operating conditions and their performance compared with other PV technologies to put into evidence the real potential. This work presents the results of a 3 months outdoor monitoring activity performed on a DSC mini‐panel made by the Dyepower Consortium, positioned on a south oriented vertical plane together with a double junction amorphous silicon (a‐Si) device and a multi‐crystalline silicon (m‐Si) device at the ESTER station of the University of Rome Tor Vergata. Good performance of the DSC mini‐panel has been observed for this particular configuration, where the DSC energy production compares favorably with that of a‐Si and m‐Si especially at high solar angles of incidence confirming the suitability of this technology for the integration into building facades. This assumption is confirmed by the energy produced per nominal watt‐peak for the duration of the measurement campaign by the DSC that is 12% higher than that by a‐Si and only 3% lower than that by m‐Si for these operating conditions. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
84.
Toward multiple maximum power point estimation of photovoltaic systems based on semiconductor theory
Jen‐Cheng Wang Yu‐Li Su Kun‐Chang Kuo Jyh‐Cherng Shieh Joe‐Air Jiang 《Progress in Photovoltaics: Research and Applications》2015,23(7):847-861
Environmental conditions, such as temperature, non‐uniform irradiation, and solar shading, deeply affect the characteristics of photovoltaic (PV) modules in PV‐assisted generation systems. Several local maximum power points (MPPs) are found in the power–voltage curve of PV systems constructed by series/parallel‐connected PV modules under partially shaded conditions. The characteristics of PV systems change unpredictably when multiple MPPs occur, so the actual MPP tracking (MPPT) becomes a difficult task. Conventional MPPT methods for the PV systems under partially shaded conditions cannot quickly find the actual MPP such that the optimal utilization of PV systems cannot be achieved. Based on the p–n junction semiconductor theory, we develop a multipoint direct‐estimation (MPDE) method to directly estimate the multiple MPPs of the PV systems under partially shaded conditions and to cope with the mentioned difficulties. Using the proposed MPDE method, the multiple MPPs of the PV systems under partially shaded conditions can be directly determined from their irradiated current–voltage and power–voltage characteristic curves. The performances of the proposed MPDE method are evaluated by examining the characteristics of multiple MPPs of PV systems with respect to different shading strengths and numbers of the shaded PV modules and also tested using the field data. The experimental results demonstrate that the proposed MPDE method can simply and accurately estimate the multiple MPPs of the PV systems under partially shaded conditions. The optimization of MPP control models and the MPPT for PV systems could be achieved promisingly by applying the proposed method. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
85.
86.
Implantable medical devices (IMDs) are critically requested for the survival of patients subject to certain serious diseases
such as bradycardia, fibrillation, diabetes, and disability, etc. Appropriate working of an active implantable medical device
(IMD) heavily relies on the continuous supply of electricity. In this sense, long-term powering and recharging of an IMD via
a highly safe, efficient and convenient way is, therefore, extremely important in clinics. Several conventional batteries,
such as lithium cell, nuclear cell and bio-fuel cell, etc., have been developed to power IMDs. Meanwhile, the recharge of
IMD from outside of the human body is also under investigation. In this paper, some of the most typical IMD batteries are
reviewed. Their advantages and disadvantages are compared. In addition, several emerging innovations to recharge or directly
drive the implanted batteries, including electromagnetic energy transmission, piezoelectric power generation, thermoelectric
devices, ultrasonic power motors, radio frequency recharging and optical recharging methods, etc., are also discussed. Some
fundamental and practical issues thus involved are summarized, and future prospects in this area are made. 相似文献
87.
综述了热沉和热电制冷器应用于LED热管理及其材料和性能优化的研究进展,提出热沉的组合使用可有效降低热电制冷器热端的温度,提高其制冷性能,而热电制冷器和热沉组合散热的性能评价与优化将是该领域未来的研究方向. 相似文献
88.
Beer Clarification by Novel Ceramic Hollow‐Fiber Membranes: Effect of Pore Size on Product Quality 下载免费PDF全文
In this work, the crossflow microfiltration performance of rough beer samples was assessed using ceramic hollow‐fiber (HF) membrane modules with a nominal pore size ranging from 0.2 to 1.4 μm. Under constant operating conditions (that is, transmembrane pressure difference, TMP = 2.35 bar; feed superficial velocity, vS = 2.5 m/s; temperature, T = 10 °C), quite small steady‐state permeation fluxes (J*) of 32 or 37 L/m2/h were achieved using the 0.2‐ or 0.5‐μm symmetric membrane modules. Both permeates exhibited turbidity <1 EBC unit, but a significant reduction in density, viscosity, color, extract, and foam half‐life with respect to their corresponding retentates. The 0.8‐μm asymmetric membrane module might be selected, its corresponding permeate having quite a good turbidity and medium reduction in the aforementioned beer quality parameters. Moreover, it exhibited J* values of the same order of magnitude of those claimed for the polyethersulfone HF membrane modules currently commercialized. The 1.4‐μm asymmetric membrane module yielded quite a high steady‐state permeation flux (196 ± 38 L/m2/h), and a minimum decline in permeate quality parameters, except for the high levels of turbidity at room temperature and chill haze. In the circumstances, such a membrane module might be regarded as a real valid alternative to conventional powder filters on condition that the resulting permeate were submitted to a final finishing step using 0.45‐ or 0.65‐μm microbially rated membrane cartridges prior to aseptic bottling. A novel combined beer clarification process was thus outlined. 相似文献
89.
本文从标准规定应力增加速率为一恒量出发,根据加荷、应力对时间的函数关系,讨论了抗折仪满足标准要求应具备的测试功能及加荷达率的确定。 相似文献
90.