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21.
Yun-Ying Chen Yi-Chieh Chang Wei-Ying Hung Hong-Ping Lin Hui-Ya Shih Wen-An Xie Shou-Nan Li Chun-Han Hsu 《国际能源研究杂志》2020,44(12):9748-9756
A simple synthetic method without organic template is proposed for the synthesis of Ni-silicate. The resulting Ni-phyllosilicates are reconstructed by hydrothermal treatment to a porous structure with a high surface area (552 m2 g−1). Notably, the residual filtrate has a Ni2+ ion content of less than 0.1 ppm, and therefore satisfies the effluent standard in Taiwan (<1.0 ppm). As a result, it can be disposed of directly without the need for additional treatment. The effects of the pH value and hydrothermal treatment time on the structure, morphology, and surface area of the Ni-silicate composites have been investigated. When applied to hydrogen production, the mesoporous Ni-silicate shows a high catalytic capability (>99%) toward ammonia decomposition at a temperature of 400°C. Overall, the proposed synthetic method is facile and easily extendable to the production of other metal-silicate materials for hydrogen generation. 相似文献
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Semi-active control is based on the use of the emerging concept of active control and passive control. The developed accumulator semi-active hydraulic damper (ASHD) is converted to interaction element (IE) of active interaction control (AIC). Systemic equations of motion, control law and control rulers of this proposed new AIC are studied in this research. A full-scale multiple degrees of freedom shaking table is tested to verify the energy dissipation of this proposed AIC, including test building without control, with passive control added involving various stiffness ratios and also with synchronic control added involving various stiffness ratios. Shock absorption of displacement can be up to 74–81% of that of the test structure with stiffness ratio = 2.3387 and 1.790 at 1st and 2nd floor under control of synchronous switch of this proposed AIC, respectively. No matter what the test structure added with various stiffeners at 1st and 2nd floor under synchronous control, test results of shock absorption ratio of acceleration show good seismic proof capability. In addition, base shear control effects of this proposed AIC method are higher than those of the test structure with various stiffeners added under passive control. These results show that AIC with stiffeners for structural control provides the characteristics of a stabilized structure under excitation of near-fault earthquake with velocity impulse action. 相似文献
24.
Shih‐Wen Hsiao Yu‐Ting Hsiao Shih‐Kai Chen Chiao‐Fei Hsu Chun‐Hsing Lee Ya‐Hui Chiang 《Color research and application》2016,41(1):72-84
Light‐emitting diodes (LEDs) have the advantage of controllable light colors and provide the optimal lighting quality against various color attributes required in different environments. However, from the humanized design point of view, beside satisfying physical demands of people, it is also important to achieve satisfaction. With a good match between the LED lighting equipment and ambient colors, the space imagery that complies with psychological needs of human beings can be found. This is expected to become a new market direction for future lighting. In this study, the LED light source feature of adjustable correlated color temperature is used to match wall colors of typical commercial spaces and for the investigation and analysis of the impact of colors of light sources and environments on human beings. The measures of mental and subjective feelings of a group of people under various circumstances have also been investigated. Multivariate analysis of variance has been conducted on three color temperatures of light sources, six wall colors, and measures of five emotion adjectives, and the correlation between these three variables has been further investigated. © 2014 Wiley Periodicals, Inc. Col Res Appl, 41, 72–84, 2016 相似文献
25.
I-Ming Hung Wei-Jen Shih Min-Hsiung Hon Moo-Chin Wang 《International journal of molecular sciences》2012,13(10):13569-13586
In order to obtain the properties of the sintered as-dried calcium phosphate with [Ca]/[P] = 1.50, the characteristics of sintered pellets have been investigated using X-ray diffraction (XRD), inductively coupled plasma-mass spectrometry (ICP-MS), Fourier-transform infrared (FT-IR) spectra, Vickers hardness indentation and scanning electron microscopy (SEM). When the pellet samples were sintered between 700 °C and 1200 °C for 4 h, the hydroxyapatite (Ca10(PO4)6(OH)2, HA) still maintained the major phase, accompanied with the rhenanite (NaCaPO4) as the secondary phase and β-tricalcium phosphate (β-Ca3(PO4)2, β-TCP) as the minor phases. In addition, the HA partially transformed to α-tricalcium phosphate (α-Ca3(PO4)2, α-TCP) and tetracalcium phosphate (Ca4(PO4)2O, TTCP), when the pellet samples were sintered at 1300 °C and 1400 °C, respectively, for 4 h. The maximum density and Vickers Hardness (HV) of sintered pellet samples were 2.85 g/cm3 (90.18% theoretical density (T.D.)) and 407, which appeared at 1200 °C and 900 °C, respectively. 相似文献
26.
Abstract A textual database deals with retrieval and manipulation of documents. It allows a user to search on‐line complete documents or parts of documents rather than attributes of documents. Resembling a formatted database which uses a data model as its underlying structure, a textual database has to base its development upon a document model. In this paper, a document model, called the ECHO model, is proposed. The ECHO model provides a document representation, called the ECHO structure, for expressing documents and operations on the representation that serve to express queries and manipulations on documents. It has the ability to provide multiple document structures for a document, a flexible search unit for retrieving textual information, and a subrange search on a textual database. In addition, the ECHO structure is relatively easy to maintain. An architecture of a textual database based on the ECHO model is also proposed. In order to improve the query performance, a refined character inversion method, called ARCIM, is proposed as the text‐access method of the Chinese textual database. The ARCIM can retrieve texts faster than a simple inversion method and requires less space overhead. 相似文献
27.
Shih‐Chien Chou 《中国工程学刊》2013,36(2):323-330
Abstract This paper proposes a label‐based information flow control model to prevent information leakage within object‐oriented systems. It offers the features of: (a) adapting to dynamic object state change, (b) adapting to dynamic role change, (c) preventing indirect information leakage, (d) detailing the control granularity to variables, (e) allowing purpose‐oriented method invocation, (f) controlling method invocation through argument sensitivity, (g) allowing declassification, and (h) allowing only trusted sources to write a variable. 相似文献
28.
Abstract A microprocessor‐based electrohydraulic servo system has been constructed and tested. It is implemented with an 8‐bit single‐chip microcomputer to control a hydraulic motor. The control algorithm is based on variable structure control principles. The experimental results show that the system is under good control and possesses a great potential for electrohydraulic servo control. 相似文献
29.
Chia-Ling Ko Wen-Cheng Chen Jian-Chih Chen Ying- Hui Wang Chi-Jen Shih Yu-Chang Tyan Chun-Cheng Hung Jen-Chyan Wang 《Materials science & engineering. C, Materials for biological applications》2013,33(6):3537-3544
This study aims to evaluate further the performance of a platelet-rich plasma (PRP) additive incorporated with calcium phosphate bone cement (CPC) in vitro to prove its efficiency as bone graft substitutes and its compatibility to be incorporated into the CPC with other techniques in clinical restoration in vivo. The growth factor release ability and the osteogenic evaluation of PRP, CPC, and PRP/CPC testing groups with 5, 10, and 15 wt.% PRP were compared in vitro. Four groups were measured using non-decalcified staining methods in vivo, which include the testing group of 10 wt.% PRP/CPC selected from the evaluation in vitro, by using both the autograft with rabbit trabecular and CPC-only as comparison groups and the group without grafting material as the control sample. The results obtained through specimen immersion show that growth factor release and alkaline phosphatase activities after osteoprogenitor cell culture had a significantly better effect on 10 and 15 wt.% PRP/CPC than on the other groups in vitro. Analysis results suggest that PRP was still retained in the CPC matrix even after 32 days of immersion. The results in vivo show that the histology of the autograft bone and the control group without grafting material exhibited fibrous connective and adipose tissues, which obviously filled the created cavity even at nine weeks after the operation. Osteoregeneration was more successful in the PRP-additive group, which accumulated bone remodeling than in the other groups. In conclusion, CPC could be a potential carrier with adequate PRP additives that bear a therapeutic potential for enhanced bone tissue regeneration. 相似文献
30.
Shih‐Fu Ling 《中国工程学刊》2013,36(2):97-103
Abstract A Galerkin based finite element method is used to solve acoustic pressure distribution in unlined or lined ducts of arbitrary profile with circular cross section. For isoparametric elements with cubic polynomials as shape functions, two elements per wavelength is proved necessary to keep solution error within 2.5%. Several examples are solved to show the capability of the derived technique, and the results, are good. 相似文献