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991.
One particular aspect of a wide range of HVAC research at the US Center for Building Technology concerned interfacing DDC with the pneumatic system for one of the existing air handling units at the CBT building itself. Using solenoid air valves induced both positive and negative air leaks in the pneumatic system; this did not occur with motorised pressure regulators, though these produced a time delay whenever the regulator's direction of rotation was reversed. Details are given of an adaptive PI algorithm with a self‐tuning regulator approach, developed at CBT and implemented on the air handler in question. From the experience, it is strongly recommended that such an algorithm should be implemented on a positional basis. 相似文献
992.
Jin-Ho Park 《The Journal of Architecture》2013,18(1):37-54
Rudolph Michael Schindler has been known as the first and foremost space architect, in his own words, whose devotion to space as defining architecture remained vital and remarkably consistent throughout his professional career. The purpose of this article is systematically to interpret Schindler's theory of space architecture, and then to discuss his theoretical project: Space Development. The first part investigates Schindler's underlying forms of conception. For Schindler, forms of architecture begin with the space architect's process of thinking, shaping, and feeling the building in the mind. Using a recently uncovered series of Schindler's 1916 lecture notes, from the Schindler archive at the University of California, Santa Barbara (UCSB), the investigation presents a new and critical examination of his theory. The second part interprets his theoretical project, Space Development, to strengthen the understanding of Schindler's notion of space architecture. Along with Space Development, Schindler also evolved two related projects in the same year, sharing the same compositional logic. This article further examines the spatial paradigm pertinent to his Space Development, investigates its relationship to two other designs, and demonstrates how his design theory became further clarified and strengthened through it in the final phase of his career. 相似文献
993.
Sung Woo Park Se Woon Choi Hyo Seon Park 《The Structural Design of Tall and Special Buildings》2013,22(9):718-728
The differential length changes of vertical members in a high‐rise building due to elastic, creep and shrinkage shortenings are of primary concern since the differential shortening of the vertical members causes unexpected damages on structural and nonstructural members. In contrast to researches on prediction methods for calculation of the amount of the shortenings, only few methods or algorithms of compensation of the differential column shortenings have been reported. In this paper, a practical compensation method using moving average correction is presented. The proposed method is applied to the compensation of the differential shortenings of the vertical members in a 70‐story high‐rise building. The performance of the moving average correction method is compared with the optimal compensation method based on simulated annealing algorithm. It is demonstrated that the magnitude of the differential shortening or the degree of the slab tilt due to the length changes in the vertical members can be controlled without using structural optimization techniques. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
994.
Jaehong Lee Daekyu Park Kihak Lee Namshik Ahn 《The Structural Design of Tall and Special Buildings》2013,22(5):454-470
In this paper, the geometric nonlinear behavior of wall‐frame tall building structures is analyzed. The governing equations of the wall‐frame systems with outrigger trusses are formulated through the continuum approach, and the whole structure is idealized as a shear‐flexural cantilever with rotational spring. The effect of shear and flexural deformation of the wall frame and outrigger trusses are considered and incorporated in the formulation of the governing equations. Geometric nonlinearity in the sense of von Karman is included in the formulation, and Newton–Raphson iterative method is employed to solve the nonlinear equations. A displacement‐based one‐dimensional nonlinear finite element model is developed. Numerical results for wall frame and mega‐column structures with outriggers are obtained and compared with the finite element package MIDAS. The proposed method is found to be simple and efficient, providing reasonably accurate results in early design stages of tall building structures. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
995.
In this study, optimizations on separation of Toluene and 1-Butanol mixture is carried out by pressure swing distillation process. New heat integration methods are applied and compared to conventional PSD process by using vapor recompression technique combined with pressure swing distillation process. New heat integration methods show positive results to decrease the utilities used in the process. A simulator Aspen HYSYS V8.4 is used for simulating all processes. Cost analysis is also performed and Aspen HYSYS V8.4 optimizer program is used for optimizing profit for the process. Pressure is also optimized for minimum heat duty requirements in the process and the ultimate concern is to minimize the total reboiler heat duties and overall operating cost for the system which results into increasing profit. 相似文献
996.
Il?Lae?Jung Young?Chan?Park Doo?Hyun?ParkEmail author 《Korean Journal of Chemical Engineering》2016,33(6):1865-1871
The effects of electrochemical reducing power on enrichment, growth, and ammonium production of freeliving diazotrophs from rhizosphere soil were evaluated. Soil bacteria were cultivated in a conventional bioreactor (CBR) and an electrochemical bioreactor (EBR), both containing a neutral red-modified graphite felt (NR-GF) cathode and a platinum anode, but with electricity charged to the EBR only. Temperature gradient gel electrophoresis identified 21 species from rhizosphere soil, and 17 and seven species from the CBR and EBR, respectively, after 40 days of incubation. Six species from the CBR and five species from the EBR were diazotrophs. The bacterial community biomass and the ammonium content in the bacterial culture were, respectively, 1.6 and 2 times higher in the EBR than in the CBR. These results indicate that the electrochemical reducing power generated from the NR-GF may be a driving force in the activation of enrichment, growth, and N2-fixing metabolism of diazotrophs. 相似文献
997.
Prakash Parthasarathy Hang Seok Choi Hoon Chae Park Jae Gyu Hwang Ho Seong Yoo Byeong-Kyu Lee Mukesh Upadhyay 《Korean Journal of Chemical Engineering》2016,33(8):2268-2286
Waste tyres have become a grave concern as their accumulation is aggregating every year. Not only the size of waste tyre has to be reduced, but also some useful energy has to be recovered out of it as the world badly requires energy from alternate sources. Pyrolysis is one such method to extract energy potential products from waste tyres. It is extensively used to generate carbon black (solid product), tyre-oil (liquid product) and syngas (gas product) from waste tyres. In that connection, this article discusses the effect of various parameters on the product composition of pyrolysis of waste tyres. The current usage of pyrolysis products and their typical characteristics are also discussed in this critique. Of late, extraction of high value added products, such as activated carbon from carbon black, and limonene from tyre-oil is gaining attention. The article also throws some light on the application and generation routes of activated carbon and limonene from waste tyres. 相似文献
998.
13-Hydroxy-9Z,15Z-Octadecadienoic Acid Production by Recombinant Cells Expressing Lactobacillus acidophilus 13-Hydratase 下载免费PDF全文
Woo-Ri Kang Chul-Soon Park Kyung-Chul Shin Kyoung-Rok Kim Deok-Kun Oh 《Journal of the American Oil Chemists' Society》2016,93(5):649-655
Recombinant Escherichia coli cells expressing linoleate 13‐hydratase from Lactobacillus acidophilus were permeabilized by treating with 0.2 M NaCl. The optimal conditions for the production of 13‐hydroxy‐9,15(Z,Z)‐octadecadienoic acid (13‐HODE) from α‐linolenic acid by permeabilized recombinant cells were pH 6.0, 40 °C, 7.5 % (v/v) methanol, 60 g/l permeabilized cells, and 15 g/l α‐linolenic acid. Under these conditions, permeabilized cells produced 7.5 g/l 13‐HODE after 6 h, with a conversion yield of 50 % (w/w) and a volumetric productivity of 1.25 g/l/h. These values were 161 and 160 % of those obtained by nonpermeabilized cells, respectively. To the best of our knowledge, this is the first report on the process optimization for the biotechnological production of 13‐HODE. 相似文献
999.
Laccase‐catalyzed synthesis of polypyrrole‐multiwalled carbon nanotube composites as energy storage materials for capacitors 下载免费PDF全文
Multiwalled carbon nanotubes (MWNTs) were coated with polypyrrole (PPy) using in situ enzymatic polymerization of pyrrole catalyzed by a laccase (benzenediol:oxygen oxidoreductase, EC 1.10.3.2) from Trametes versicolor. Transmission electron microscopy revealed that the MWNTs were uniformly coated with very thin layers of PPy without any indication of globular polymer aggregate formations. The enzymatic synthesis of the MWNTs/PPy composites was quite simple being performed in a one‐pot aqueous solution (pH 4.0) under mild reaction conditions. The potential of the composites with respect to the development of energy storage devices was demonstrated by fabricating a two‐electrode coin cell capacitor (diameter 20 mm, thickness 1.6 mm) utilizing the composites as electrode materials. The capacitance of the cell was 28.0 F g?1 for the electrode material as measured by a galvanostatic charge–discharge method. The energy density and power density were 2.55 and 805 W kg?1, respectively, which were close to those of the capacitors classified as ultracapacitors. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43307. 相似文献
1000.
Synthesis of aminated glycidyl methacrylate grafted rice husk and investigation of its anion‐adsorption properties 下载免费PDF全文
In this study, we focused on the synthesis, characterization, and adsorption capacity testing of aminated glycidyl methacrylate grafted rice husk (RH‐g‐GMA–Am). Our goal was to obtain a high‐performance surface for the adsorption of various anions. Glycidyl methacrylate grafted rice husk (RH‐g‐GMA) was prepared by the graft copolymerization of glycidyl methacrylate with rice husk; the product was further subjected to an amination reaction. The surface properties, sorption characteristic functional groups, isotherm and kinetic studies, pore diffusion models, and effects of the temperature and pH on the material properties were studied under batch conditions. The IR spectroscopy results show additional surface functional groups for RH‐g‐GMA–Am. The adsorptions of and on RH‐g‐GMA–Am were found to follow pseudo‐second‐order kinetics; this indicated a possible dominant role played by chemisorption. The rate‐limiting step for mass transfer was found to be boundary layer diffusion. Furthermore, the sorption isotherms for and fit the Langmuir model. The amination of RH‐g‐GMA drastically increased the removal efficiency from 3 to 82% and from 6 to 93% for and , respectively. Moreover, RH‐g‐GMA–Am exhibited a better removal efficiency in the pH range of 4–6.5. Regeneration studies revealed that the surface of RH‐g‐GMA–Am could be regenerated repetitively by simple acid washing with an insignificant decrease in the active surface for consecutive adsorptions. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43002. 相似文献