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71.
A double-skin system (double-glazed external wall) is an effective passive system that can be used to decrease solar heat gain into buildings. Detailed information on the thermal distribution of double-skin facades is necessary to design better systems that can provide thermal comfort and conserve energy. In this study, the three-dimensional thermal characteristics of double-skin facades that had the ventilation opening installed partially and were screened partially by the adjacent buildings were investigated by field measurements. To that end, field measurements were carried out on the double-skin exterior wall (9.4 m high and 27.0 m wide) installed in an atrium located in the west of an existing building during cooling period for typical summer conditions. Maximum air change rate of natural ventilation through the bottom opening up to the top opening is about 20–25 [1/h], the reduction ratio of total solar heat gain compared with those of non-natural ventilation is about 25%. The exhaust solar heat gain is about 100 W/m2 per inner glass surface area of the double-skin facades. Air temperature distribution of air space in the double skin was ranged from 30 °C to 44 °C, and heat gain difference ranged from 50 W/m2 to 130 W/m2. The influence of the ventilation openings and the shade conditions on temperature distribution of double skin is found to be significant and the double-skin system was verified to reduce the cooling loads effectively.  相似文献   
72.
Journal of Materials Science: Materials in Electronics - Fabrication and characterization of methylammonium lead iodide perovskite solar cells incorporated with methylammonium bromide (MABr),...  相似文献   
73.
Inverse spinel zinc stannate (Zn2SnO4, ZTO) films were deposited onto fused quartz glass substrates heated at 800 °C by rf magnetron sputtering using a ceramic ZTO target (Zn:Sn = 2:1). H2 flow ratios [H2/(Ar + H2)] were controlled from 0 to 30% during the depositions. ZTO films deposited at 800 °C possessed a polycrystalline inverse spinel structure. The lowest resistivity of 1.1 × 10− 2 Ω cm was obtained for a ZTO film deposited at 20% H2 flow ratio. The transmittance of the ZTO film was approximately 80% in the visible region.  相似文献   
74.
The first electron beam was stored in SPring-8 storage ring in March 1997. An overview of the 13 years’ operational experience concerning the vacuum system of the SPring-8 storage ring is presented. The evolution of the vacuum system and their performance are summarized. Moreover, the main vacuum failures and their impact on accelerator operation are described in detail. We analyze the relationship between the difference types of vacuum failure and downtime of user experiment.  相似文献   
75.
76.
We have developed a novel technique for mass production of microfabricated capillary array electrophoresis (mu-CAE) plastic chips for high-speed, high-throughput genetic analysis. The mu-CAE chips, containing 10 individual separation channels of 50-microm width, 50-microm depth, and a 100-microm lane-to-lane spacing at the detection region and a sacrificial channel network, were fabricated on a poly(methyl methacrylate) substrate by injection molding and then bonded manually using a pressure-sensitive sealing tape within several seconds at room temperature. The conditions for injection molding and bonding were carefully characterized to yield mu-CAE chips with well-defined channel and injection structures. A CCD camera equipped with an image intensifier was used to monitor simultaneously the separation in a 10-channel array with laser-induced fluorescence detection. High-performance electrophoretic separations of phiX174 HaeIII DNA restriction fragments and PCR products related to the human beta-globin gene and SP-B gene (the surfactant protein B) have been demonstrated on mu-CAE plastic chips using a methylcellulose sieving matrix in individual channels. The current work demonstrated greatly simplified the fabrication process as well as a detection scheme for mu-CAE chips and will bring the low-cost mass production and application of mu-CAE plastic chips for genetic analysis.  相似文献   
77.
The properties of a titanium nitride film prepared by a DC arc plasma jet were investigated by microscopic observations, composition analysis, and hardness measurements. Scanning electron microscopy showed that the film was composed of three phases, designated the A, B, and C regions from the outer surface. The existence of three regions was also supported by composition analysis and hardness measurements on the cross section. XRD patterns showed the presence of -TiN in the A region. In the B region, a number of voids were observed, which have never been reported in previous papers. These were made up from specific crystallographic surfaces. The C region also had a few voids which were somewhat different from those in the B region. In the matrix, an acicular texture was found and identified as -Ti solid solution by XRD. The cross section of the film changed the color determined by the nitrogen content.  相似文献   
78.
Propofol's effect on hypoxic pulmonary vasoconstriction during one-lung ventilation (OLV) has not been determined. Twenty patients who had long-term OLV for esophageal surgery were allocated randomly to one of two study groups; one in which isoflurane administration preceded propofol, and another in which sevoflurane administration preceded propofol. Arterial and mixed venous blood samples and hemodynamics were measured as follows: before OLV, during OLV, OLV at 4 cm of positive end-expiratory pressure (PEEP), OLV after conversion from volatile anesthetics to propofol, OLV at 4 cm of PEEP, and after OLV. After the application of 4 cm of PEEP during propofol anesthesia, PaO2 increased significantly in both groups. The shunt fraction (Qs/Qt) increased significantly after the initiation of OLV in both groups and decreased significantly after the conversion from volatile anesthetics to propofol in both groups. Propofol can be used safely during OLV because PaO2 increased after the application of 4 cm of PEEP during propofol anesthesia, and Qs/Qt decreased significantly after the conversion from inhaled anesthetics to propofol anesthesia. IMPLICATIONS: During one-lung ventilation, the arterial partial pressure of oxygen values with propofol were greater than those with isoflurane and sevoflurane, and shunt fraction values with propofol were lower than those with both volatile anesthetics. Propofol improved oxygenation and shunt fraction during one-lung ventilation compared with volatile anesthetics.  相似文献   
79.
BACKGROUND: Regulation of perioperative albumin synthesis under parenteral (PN) and enteral (EN) nutrition was investigated. METHODS: Rats were divided into PN and EN groups. Both groups received the same regimen of artificial nutrition for 7 days and then underwent 70% hepatectomy. Serum albumin and mRNA levels of albumin and its promoter-binding nuclear factors (C/EBPalpha, beta, and DBP) were measured. RESULTS: Serum albumin and albumin mRNA in the PN group were significantly lower than those in the EN group at 72 hours after hepatectomy. Preoperative and postoperative DBP and C/EBPalpha mRNA levels in the EN group were significantly higher than those in the PN group. CONCLUSION: Serum albumin was well maintained by EN after hepatectomy owing to an early recovery of albumin mRNA level and its nuclear factor mRNA levels (C/EBPalpha and DBP). Compared with PN, EN is a more advantageous from of perioperative nutrition as pertains to albumin synthesis.  相似文献   
80.
A noncontact, nonmechanical scanning, wide-field spectral interference microscope is developed for simultaneous measurement of three-dimensional step-height of discontinuous objects and tomographic imaging. A superluminescent diode (SLD) is used as a broadband light source and a liquid-crystal Fabry-Perot interferometer (LC-FPI) as a frequency-scanning device. By means of changing the injection current to the SLD, the spectral profile of the SLD is equalized, and a constant light input to the interferometer is achieved over the entire frequency-scan range. The Fourier-transform technique is used to determine both the amplitude and the phase of spectral fringe signals. Three-dimensional height distribution of a discontinuous object is obtained from the phase information, whereas optically sectioned images of the object are obtained either from the amplitude information alone or from the combination of both the amplitude and phase information. Experimental results with submicrometer resolution are presented for both step-height measurement and tomographic sectioning.  相似文献   
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