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吴德绳 《建设科技(建设部)》2007,(19):68-69
如何提高空调机组的能效目前已经成为空调行业的发展方向。在小型中央空调领域,日本厂家从90年代初开始着手将变频技术成功应用于"商用多联机系统",并从90年代的"交流变频"技术发展到2003年开始采用"直流变频"技术。同时,艾默生旗下的环境优化技术部门从1993年开始着手研发"数码涡旋"变容量技术,并从1997年开始在机房空调应用中测试,相继开发船舶用冷冻机组,并供应亚洲与中国市场。 相似文献
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Partha Majumdar Andrey Chernykh Hanzhen Bao Elizabeth Crowley Mingqiang Zhang James Bahr Michael Weisz Chad Ulven Tingting Zhou Robert B. Moore Bret J. Chisholm 《Polymer Engineering and Science》2014,54(7):1648-1663
An array of perfectly alternating polycarbonate‐polydimethylsiloxane (PC‐PDMS) multiblock copolymers possessing systematic variations in block molecular weights were successfully produced by coupling preformed PC and PDMS telechelic oligomers using hydrosilylation. Based on gel permeation chromatography results, the multiblock copolymers were essentially void of the oligomeric precursors. Despite the relatively large difference in solubility parameter between PC and PDMS, the multiblock copolymers exhibited significant partial miscibility between the two phases. As expected, the degree of partial miscibility was dependent on the molecular weight of the blocks with the extent of partial miscibility increasing with decreasing block molecular weights. Morphological characterization using small angle X‐ray scattering showed that, at a given PC block molecular weight, the uniformity of the two phase morphology increased with increasing PDMS block molecular weight, which is consistent with a decrease in the extent of phase mixing with increasing PDMS block molecular weight. POLYM. ENG. SCI., 54:1648–1663, 2014. © 2013 Society of Plastics Engineers 相似文献
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Majumdar Dhrubajyoti Tüzün Burak Pal Tapan Kumar Das Sourav Bankura Kalipada 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(3):1159-1176
Journal of Inorganic and Organometallic Polymers and Materials - We serendipitously designed one novel 1D hetero-binuclear Zn(II)-Pb(II) coordination polymer, namely... 相似文献
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T. J. Majumdar 《International journal of remote sensing》2013,34(11):2207-2208
Thermal inertia is a measure of the resistance power of a material to changes in temperature, and this property of a material is very important from the aspects of hydrological and geological studies. Generation of thermal inertia images and their possible geological application has been attempted over the Indian peninsula and its surroundings using INSAT-1D (Indian National Satellite) VHRR (Very High Resolution Radiometer) day-time and consecutive nighttime data. Using the concepts of energy balance computation and also using the procedures involved in albedo computation and the digital registration of day time and pre-dawn imagery, a thermal inertia map over the whole peninsula and its surroundings has been generated. An attempt has been made to correlate the thermal inertia anomalies with sub-surface structures. The analysis done over the subcontinent shows the possibility of delineation of subsurface structures by thermal inertia mapping. 相似文献
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Pinaki Majumdar Sabyasachi Tarat 《Journal of Superconductivity and Novel Magnetism》2013,26(5):1787-1793
The mean field theory due to Bardeen, Cooper, and Schrieffer (BCS) provides the conceptual foundation of our understanding of superconductivity, but many examples over the last few decades have forced condensed matter physicists to extend the BCS framework. In particular, the extension to strong coupling, the BCS to Bose–Einstein condensation (BEC) crossover, requires the treatment of amplitude and phase fluctuations above the mean field state. Similarly, the presence of disorder can lead to strong inhomogeneity in the pairing amplitude, enhance phase fluctuations, and suppress the transition temperature. Finally, magnetic scattering quickly leads to a gapless superconducting state and then the loss of order. All of these involve physics beyond the BCS scenario. We employ a real space method that reduces to inhomogeneous mean field theory in the ground state, but fully retains the amplitude and phase fluctuations of the pairing field at finite temperature. This paper reviews some of our work in the weak to strong coupling (BCS–BEC) crossover, the disorder driven superconductor-insulator transition, and the role of magnetic impurities. 相似文献
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Kausik Kumar Majumdar D. Dutta Majumder 《International journal of systems science》2013,44(15):889-901
Uncertain information processing by fuzzy if–then rules has received much attention. Here we have taken a different path to model a system, about which we do not have precise information, namely modelling the system by fuzzy-valued functions without resorting to fuzzy if–then rules. As a result, the phase (state) space of the system becomes a fuzzy set and the underlying fuzzy mapping becomes a fuzzy attainability set mapping. Uncertain or fuzzy dynamical systems have been defined in terms of fuzzy attainability set mappings. Fuzzy differentiable dynamical systems have been discussed with a particular emphasis on fuzzy differential inclusion (FDI) relations. An evolutionary algorithm for solving one-dimensional FDIs has been developed. A model of the creation of a tropical cyclone in the form of a vortex, created by winds coming from different directions and colliding under certain conditions, has been proposed in terms of FDIs. A model has been considered for the highly uncertain system of evolution of a tumour in a human body and an FDI relation model of the whole system has been proposed and simulated. The model of an evolution of turbulence, as a random occurrence of vortices in a three-dimensional dynamic fluid, has been proposed and simulated, where each vortex is modelled by a fuzzy-valued function, where uncertain parameter and variable values are fuzzy numbers. All the systems represented by FDI relations have been simulated with the help of the evolutionary algorithm mentioned above. 相似文献
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Transition Metal Oxides: Electron‐Beam‐Induced Perovskite–Brownmillerite–Perovskite Structural Phase Transitions in Epitaxial La2/3Sr1/3MnO3 Films (Adv. Mater. 18/2014) 下载免费PDF全文
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We analyze charity requests registered on the Random Acts of Pizza online community and examine the content of postings and non-content characteristics to identify features that are associated with the success of donation. We find that the presence of rational and credible appeals in a message increases the likelihood of receiving a donation, whereas the mere presence of negative emotional appeal does not do so. Our research is useful for those who like to make persuasive charity requests on online platforms. 相似文献