Ting‐Hsiang Chang  Chung‐Wei Kung  Hsin‐Wei Chen  Tzu‐Yen Huang  Sheng‐Yuan Kao  Hsin‐Che Lu  Min‐Han Lee  Karunakara Moorthy Boopathi  Chih‐Wei Chu  Kuo‐Chuan Ho 《Advanced materials (Deerfield Beach, Fla.)》2015,27(44):7229-7235

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Jung Ho Yoon  Kyung Min Kim  Seul Ji Song  Jun Yeong Seok  Kyung Jean Yoon  Dae Eun Kwon  Tae Hyung Park  Young Jae Kwon  Xinglong Shao  Cheol Seong Hwang 《Advanced materials (Deerfield Beach, Fla.)》2015,27(25):3811-3816

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Jae Woong Jung  Jea Woong Jo  Chu‐Chen Chueh  Feng Liu  Won Ho Jo  Thomas P. Russell  Alex K.‐Y. Jen 《Advanced materials (Deerfield Beach, Fla.)》2015,27(21):3310-3317

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Yufei Zhao  Guangbo Chen  Tong Bian  Chao Zhou  Geoffrey I. N. Waterhouse  Li‐Zhu Wu  Chen‐Ho Tung  Lorna J. Smith  Dermot O'Hare  Tierui Zhang 《Advanced materials (Deerfield Beach, Fla.)》2015,27(47):7824-7831

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Po‐Hsun Ho  Yi‐Ting Liou  Chien‐Hsun Chuang  Shih‐Wei Lin  Chi‐Yang Tseng  Di‐Yan Wang  Chia‐Chun Chen  Wen‐Yi Hung  Cheng‐Yen Wen  Chun‐Wei Chen 《Advanced materials (Deerfield Beach, Fla.)》2015,27(10):1724-1729

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Yusin Pak  Namsoo Lim  Yogeenth Kumaresan  Ryeri Lee  Kihyeun Kim  Tae Heon Kim  Sang‐Mook Kim  Jin Tae Kim  Heon Lee  Moon‐Ho Ham  Gun‐Young Jung 《Advanced materials (Deerfield Beach, Fla.)》2015,27(43):6945-6952

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Rupak K. Banerjee  Madhura Karve  Jong Ho Ha  Dong Hwan lee  Young I. Cho 《Numerical Heat Transfer, Part A: Applications》2013,63(10):735-753

Air cooled steam condensers (ACSC) consist of finned-tube arrays bundled in an A-frame structure. Inefficient performance under extreme temperature operating conditions is a common problem in ACSCs. The purpose of this study was to improve the heat transfer characteristics of an annular finned-tube system for better performance in extreme climatic conditions. Perforations were created on the surface of the annular fins to increase heat transfer coefficient (h). Mesh generation and finite volume analyses were performed using Gambit 2.4.6 and Fluent 6.3 with an RNG k–? turbulent model to calculate pressure drop (ΔP), heat flux (q), and heat transfer coefficient (h). Solid (no perforations) finned-tubes were simulated with free stream velocity ranging between 1 m/s–5 m/s and validated with the published data. Computations were performed for perforations at 30° interval starting at ±60°, ±90°, ±120°, ±150°, and ±180° from the stagnation point. Five cases with single perforation and three cases with multiple perforations were evaluated for determining the maximum q and h, as well as minimum ΔP. For the perforated case (perforations starting from 60° at interval of 30°), the fin q and h performance ratios increased by 5.96% and 7.07%, respectively. Consequently, the fin ΔP performance ratio increased by 11.87%. Thus, increased q and h is accompanied with a penalty of higher ΔP. In contrast, a single perforation location at 120° provided favorable results with a 1.70% and 2.23% increase in q and h performance ratios, respectively, while there was a relatively smaller increase (only 1.39%) of ΔP performance ratio. Perforations in the downstream region at ±120°, ±150°, and ±180° also resulted in a similar favorable outcome. Furthermore, the spacing of the fins along the arms of an A-frame ACSC was altered to decrease ΔP across the finned-tube array. Fin spacing in the A-frame structure with sparsely spaced fins in the center resulted in a 1.80% reduction in ΔP. Thus, penalty in ΔP for a perforated fin can possibly be offset by changing the fin spacing along the arms of an A-frame structure.  相似文献   

    

Ho Chang  Wei-An Chen  Shu-Hua Chien  Chih-Chieh Chen 《Solar Energy》2010,84(1):130-25589

This research coats a commercial TiO₂ nanoparticle Degussa P25 with good roundness and size uniformity on an indium tin oxide (ITO) glass substrate and to be photoelectrical electrode by electrophoresis deposition. It combined with dye N719, electrolyte I^-/ and counter-electrode of Pt layer to produce dye-sensitized solar cells (DSSCs). Through the electrophoretic technique, a multilayer film of an appropriate thickness is deposited in the suspension containing TiO₂ nanoparticles and isopropanol. In this process, electric current, voltage, and the number of deposition cycles are well controlled to obtain a single TiO₂ film of around 3.3 μm thick. Stacking is then performed to obtain a multilayer-typed TiO₂ film of around 12 μm thick. As the sintering temperature reaches 400 °C, the prepared multilayer TiO₂ film with a good compactness can increase the dye adsorption capability of the thin film and enhance its adsorption percentage. In addition, the heat treatment will transfer a portion of the rutile crystalline into the anatase crystalline, resulting in better material properties for DSSCs application. DSSCs produced are exposed to metal halide lamp and their energy conversion efficiency is measured. The I-V curve of the produced DSSCs shows that it has an excellent energy conversion efficiency of 6.9%.  相似文献   

    

Tzung-Hua Lin  Kuo-Chuan Ho   《Solar Energy Materials & Solar Cells》2006,90(4):506-520

In this study, two conducting polymers, polyaniline (PANI) and poly(3,4-ethylenedioxythiophene) (PEDOT), were used to construct an electrochromic device (ECD). PANI was employed as the anodic coloring polymer while PEDOT was used as the cathodic coloring polymer. The electrochemical and optical properties of PANI, which has a coloration efficiency of 25 cm²/C at 570 nm, were coupled with the complementary coloring material, PEDOT, which has a coloration efficiency of 206 cm²/C at 570 nm. A suitable operating potential window was switched between −0.6 and 1.0 V to explore the cycle life of the ECD. We tested the PANI–PEDOT ECD, which consisted of PANI, PEDOT, and an organic electrolyte containing 0.1 M LiClO₄ in propylene carbonate and 1 mM HClO₄. The transmittance of the ECD at 570 nm changed from 58% (−0.6 V) to 14% (1.0 V) with a coloration efficiency of 285 cm²/C. Within the selected operating voltage range, the PANI–PEDOT ECD could be cycled for up to 2×10⁴ cycles.  相似文献   

    

Kun-Mu Lee  Vembu Suryanarayanan  Kuo-Chuan Ho   《Solar Energy Materials & Solar Cells》2006,90(15):2398-2404

The optimization of solar energy conversion efficiency of dye-sensitized solar cells (DSSCs) was investigated by the tuning of TiO₂ photoelectrode's surface morphology. Double-layered TiO₂ photoelectrodes with four different structures were designed by the coating of TiO₂ suspension, incorporated with low and high molecular weight poly(ethylene glycol) as a binder. Among these four systems, P2P1, where P1 and P2 correspond to the molecular weight of 20,000 and 200,000, respectively, showed the highest efficiency under the conditions of identical film thickness and constant irradiation. This can be explained by the larger pore size and higher surface area of P2P1 TiO₂ electrode than the other materials as revealed by scanning electron microscopic (SEM) and Brunauer–Emmett–Teller (BET) analyses. Electrochemical Impedance Spectroscopy (EIS) analysis shows that P2P1 formulation displayed a smaller resistance than the others at the TiO₂/electrolyte interface. The best efficiency (η) of 9.04% with the short-circuit photocurrent density (J_sc) and open-circuit voltage (V_oc) of 18.9 mA/cm² and 0.74 V, respectively, was obtained for a solar cell by introducing the light-scattering particles to the TiO₂ nanoparticles matrix coated on FTO electrode having the sheet resistivity of 8 Ω/sq.  相似文献