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91.
We have developed a simulation system for a year-round assessment of environmental comfort, energy conservation, and CO2 emissions in buildings and street blocks where active utilization of sunshine, vegetation and solar energy resources is fully considered. An analysis model has been constructed for handling interactions between highly complex street-block wide solar radiation patterns and building air-conditioning load. As a demonstration case of the present system, coupled solar radiation-thermal load analysis for an eleven-story office building has been performed. By comparing the result of a building located in a city block with a reference case of a self-standing building, the proper arrangement of buildings and spaces such as solar reflectance of building surface may be proposed.  相似文献   
92.
While road pricing (RP) is considered one of the most effective means of traffic demand management (TDM), its poor acceptability has been the greatest impediment to its implementation. The authors propose a `parking deposit system? (PDS) as an alternative RP scheme, and the aim of this study is to examine PDS?s superiority focusing primarily on acceptability. To mutually verify the acceptability of PDS and conventional RP, the authors conducted a survey in the city of Nagoya, the third-largest incorporated city and the fourth most populous urban area in Japan. This survey distributed a comprehensive questionnaire to visitors and business establishments, in and around the city, eliciting a significant response. In this study process, the authors firstly built the decision-making structure model of RP/PDS by public/business establishment to clarify the decisionmaking mechanism in detail. Secondly, the approval models were built to estimate the differentia of the acceptability between RP and PDS. From this study PDS can be thought to have the higher acceptability, and to be useful measure as an alternative RP scheme.  相似文献   
93.
This note first defines a class of cylindrical polyarenes polycyclic aromatic hydrocarbons (PAHs) C2(m+ 1)nH2n, for which the periphery is acenic. From this class the leapfrog algorithm derives the second class of cylindrical PAHs C6nmH4n, where the periphery is phenacenic. One further application of this algorithm to the second class leads to the third class of cylindrical PAHs C12nmH8n, where the less regular periphery has 2n capes (i.e., hexagons exposed on four adjacent sides to the external “sea” of space). Each molecule in the second and third classes is totally covered by aromatic sextets, that is, appears related to a fully benzenoid hydrocarbon (FBH). The Pauling bond order, and several new indices derived from the Pauling bond order and Clar sextet counts are calculated for the three classes with increasing numbers of carbons. This calculation suggests that a typical cylindrical PAH becomes more graphite-like than a typical flat FBH.  相似文献   
94.
ABSTRACT The permeation of iron(III) chloride through a liquid membrane of tri-n-octylamine dissolved in benzene supported on a microporous polyethylene hollow fiber has been studied. The initial permeation rate was explained as the sum of film resistances in the aqueous phases, a membrane resistance and two inter-facial reaction resistances.  相似文献   
95.
OBJECTIVES: This study examined the changes in myocardial energy metabolism during myocardial ischemia after "remote preconditioning" and investigated the involvement of adenosine receptors in the mechanisms of this effect. BACKGROUND: Recent studies have indicated that a brief period of ischemia and reperfusion (ischemic preconditioning, PC) in a remote organ reduces myocardial infarct size (IS) protecting against subsequent sustained myocardial ischemia. However, the mechanisms of "remote PC" remain unclear. We assessed myocardial energy metabolism during sustained myocardial ischemia and reperfusion after renal PC (RPC), in comparison with that after myocardial PC (MPC) in open-chest rabbits. It has been established that adenosine receptors are involved in the mechanisms of MPC. METHODS: Rabbits that had been anesthetized with halothane were divided into six groups. The control (CNT) group underwent 40-min coronary occlusion followed by 120 min reperfusion. Before the procedure, the MPC group underwent an additional protocol of 5 min coronary artery occlusion and 20 min reperfusion, and the RPC group received a 10 min episode of renal artery occlusion and 20 min reperfusion. In additional experimental groups, 8 sulfophenyl-theophylline (SPT, 10 mg/kg), an adenosine receptor inhibitor, was intravenously injected before the 40 min myocardial ischemia (SPT, MPC + SPT and RPC + SPT groups, respectively). Myocardial levels of phosphocreatine (PCr), ATP and intracellular pH (pHi) were measured by 31P-NMR spectroscopy. RESULTS: RPC and MPC delayed the decreases in ATP levels, preserved pHi during 40-min myocardial ischemia and resulted in better recovery of ATP and PCr during 120 min reperfusion compared with the controls. SPT abolished the improvement in myocardial energy metabolism and the reduction in myocardial IS caused by MPC or RPC. Myocardial IS in the CNT (n = 8), MPC (n = 9), RPC (n = 9), SPT (n = 6), MPC + SPT (n = 8) and RPC + SPT (n = 8) groups averaged 42.8+/-3.5%, 18.2+/-1.8%*, 19.6+/-1.3%*, 44.9+/-5.0%, 35.6+/-2.7% and 34.8+/-3.6% of the area at risk (*p < 0.05 vs. CNT), respectively. CONCLUSIONS: PC in a remote organ, similar to MPC, improved myocardial energy metabolism during ischemia and reperfusion and reduced IS in vivo by an adenosine-dependent mechanism in rabbits.  相似文献   
96.
A family I.3 lipase from Pseudomonas sp. MIS38 (PML) contains 12 repeats of a nine-residue sequence motif in the C-terminal region. To elucidate the role of these repetitive sequences, mutant proteins PML5, PML4, PML1, and PML0, in which 7, 8, 11, and all 12 of the repetitive sequences are deleted, and PMLdelta19, in which 19 C-terminal residues are truncated, were constructed. Escherichia coli DH5 cells carrying the Serratia marcescens Lip system permitted the secretion of the wild-type and all of the mutant proteins except for PMLdelta19, although they were partially accumulated in the cells in an insoluble form as well. Both the secretion level and cellular content of the proteins decreased in the order PML > PML5 > PML4 > PML1 > PML0, indicating that repetitive sequences are not required for secretion of PML but are important for its stability in the cells. All the mutant proteins were purified in a refolded form and their biochemical properties were characterized. CD spectra, the Ca2+ contents, and susceptibility to chymotryptic digestion strongly suggested that the five repetitive sequences remaining in PML5 are sufficient to form a beta-roll structure, whereas the four in PML4 are not. PML5 and PMLdelta19 showed both lipase and esterase activities, whereas PML4, PML1, and PML0 were inactive. These results suggest that the enzymatic activity of PML is not seriously affected by a deletion or truncation at the C-terminal region as long as a succession of repetitive sequences can build a beta-roll structure.  相似文献   
97.
The thermally stimulated current (TSC) technique has been used to investigate molecular relaxation in poly(ethylene terephthalate) (PET) films unstretched and biaxially stretched at 90 and 95 °C. Unstretched PET films show two peaks at 77 and 90 °C corresponding to α and ρ relaxation processes, respectively. The α relaxation is associated with the main glass transition of the material. The ρ peak with lower intensity is attributable to permanent dipoles. Both biaxially stretched samples show one TSC peak at 95 °C, supposed to correspond to ρ relaxation. The disappearance of the α peak, accompanied by the displacement of the ρ peak to higher temperature, is the result of the higher thermal stability of the permanent dipoles, which is strongly influenced by the stiffening of amorphous parts and the crystallization by stretching. In both stretched samples, the continuous distribution of pre-exponential factors over activation energies observed might correspond to a single relaxation mode. The kinematics of stretching PET has been discussed in terms of activation energy and temperature dependence of relaxation time. © 1999 Society of Chemical Industry  相似文献   
98.
The objective of this study is to compare the spinnability, morphology, structure, mechanical properties, and cell compatibility of the silk fibroin nanofiber nonwoven electrospun fabrics using aqueous (AQ) solution and formic acid (FA) solution. The lower limit concentration was 5?wt% and 3?wt% of AQ solution and FA solution for electrospinning, respectively. The fiber diameter of electrospun fabric using FA solution was larger than that using aqueous solution at the same concentration. The secondary structure contents of silk fabrics were same between AQ and FA solutions. FA was remained in silk nanofibers, and the remained FA could be neutralized. Young’s modulus and cell adhesion on electrospun fabric using FA was lower than that using AQ solution. On the contrary, lower cell proliferation rate on electrospun fabric using FA was kept even after neutralization.  相似文献   
99.
The Pk-glpK gene, which encodes glycerol kinase (GK) from a hyperthermophilic archaeon Pyrococcus kodakaraensis KOD1, was cloned and expressed in Escherichia coli. The amino acid sequence of this enzyme (Pk-GK) deduced from the nucleotide sequence showed 57% identity with that of E. coli GK and 47% identity with that of human GK. Pk-GK, which has a molecular weight of 55902 (497 amino acid residues), was purified from E. coli and characterized. Despite the high sequence similarity, Pk-GK and E. coli GK are greatly divergent in structure and function from each other. Unlike E. coli GK, which exists as a tetramer, Pk-GK exists as a dimer. The preferred divalent cation for Pk- GK is Co2+, instead of Mg2+. The optimum pH and temperature for Pk-GK activity are 8.0 and 80 degrees C, respectively. Pk-GK can utilize other nucleoside triphosphates than ATP as a phosphoryl donor. It is fairly resistant to an allosteric inhibitor of E. coli GK, fructose-1,6- bisphosphate. Determination of the kinetic parameters indicates that the Km value of the enzyme is 15.4 microM for ATP and 111 microM for glycerol and its kcat value is 940 s(-1). The enzyme was shown to be fairly resistant to irreversible heat inactivation and still retained 50% of its enzymatic activity even after heating at 100 degrees C for 30 min. Construction of a model for the three-dimensional structure of the enzyme suggests that the formation of extensive ion-pair networks is responsible for the high stability of this enzyme.   相似文献   
100.
By a reduced-scale wind-tunnel experiment, we investigate the dispersion behavior of exhaust gas from automobiles. Based on the results of single-vehicle cases in Part I of our work, we consider vehicle queues consisting of passenger cars (P) and small-size trucks (T). The roles of the vehicles before and after the gas-emitting vehicle are as follows. By their turbulent wake, the preceding vehicles make the concentration field approximately symmetric in the spanwise direction despite the significant lateral offset of the exhaust pipe. The vehicles behind the gas-emitter expand the exhaust plume considerably in the spanwise direction; T expands the plume also in the vertical direction in its roll-up wake, while P scoops up the oncoming plume only around the centerline. For vehicle queues of mixing ratio P:T=2:1, the concentration fields when one of the component vehicles emit the gas are measured. It turns out that the plume shape is determined mostly by the type of the gas-emitting vehicle whereas the type of the following vehicles has minor effect. We also present an analytical procedure to approximate the overall contribution from all the queue-forming vehicles by a Gaussian line-source plume formula.  相似文献   
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