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1.
<正>我们将原来用作工厂/办公的一栋钢结构的老建筑翻新成一位艺术家未来几十年的工作场所。为了增强建筑的性能,我们应用了防火涂料,并进行了结构加固。原有建筑的建造基于"数量重于质量"的价值观念,所以40年之后,各种裂缝和变形遍布建筑,甚至在新涂料和装饰的映衬下更加清晰可见。我们试图将这些裂缝和变形变为独特的、能够使人经历意想不到体验的空间。高桥理子是最受欢迎的艺术家之一,她的作品受到广泛认可,并向  相似文献   
2.
Accumulating data indicates that certain microRNAs (miRNAs or miRs) are differently expressed in samples of tumors and paired non-tumorous samples taken from the same patients with colorectal tumors. We examined the expression of onco-related miRNAs in 131 sporadic exophytic adenomas or early cancers and in 52 sporadic flat elevated adenomas or early cancers to clarify the relationship between the expression of the miRNAs and the endoscopic morphological appearance of the colorectal tumors. The expression levels of miR-143, -145, and -34a were significantly reduced in most of the exophytic tumors compared with those in the flat elevated ones. In type 2 cancers, the miRNA expression profile was very similar to that of the exophytic tumors. The expression levels of miR-7 and -21 were significantly up-regulated in some flat elevated adenomas compared with those in exophytic adenomas. In contrast, in most of the miR-143 and -145 down-regulated cases of the adenoma-carcinoma sequence and in some of the de novo types of carcinoma, the up-regulation of oncogenic miR-7 and/or -21 contributed to the triggering mechanism leading to the carcinogenetic process. These findings indicated that the expression of onco-related miRNA was associated with the morphological appearance of colorectal tumors.  相似文献   
3.
4.
Edible mushrooms contain considerable amounts of the potent natural antioxidant 2‐thiol‐l ‐histidine‐betaine (l ‐ergothioneine, ESH). The objective of this study was to evaluate the effects of extraction solvents, common cooking methods and storage conditions on the ESH content, total phenols (TPs) and antioxidant capacity of the edible mushroom Flammulina velutipes fruiting body and its hot water extract that had been stored at different temperatures. Regarding cooking procedures, boiling in water resulted in the highest losses of antioxidant activity of both ESH and TPs. Most of the losses of ESH and TPs were detected in the cooking water. The ESH contents in the raw mushroom fruiting bodies significantly decreased after 8 days of refrigerated storage under both dark and fluorescent lighting conditions. However, the TP content in the raw mushroom stored under fluorescent lighting significantly increased during 10 days of refrigeration. In contrast, the ESH and TP contents as well as DPPH radical scavenging ability of the fruiting bodies remained unchanged for up to 15 days of frozen storage at ?18 °C. The same behaviour was obtained with the mushroom extract packed in plastic tubes. The correlation between DPPH radical scavenging activity and ESH contents was higher than that for TP compounds.  相似文献   
5.
Ceramic thermal barrier coatings (TBCs) are a very important technology for protecting the hot parts of gas turbines (GTs) from a high-temperature environment. The coating stress generated in the operation of GTs brings cracking and peeling damage to the TBCs. Thus, it is necessary to evaluate precisely such coating stress in a TBC system. We have obtained a stress-strain curve for a freestanding ceramic coat specimen peeled from a TBC coated substrate by conducting the bending test. The test results have revealed that the ceramic coating deforms nonlinearly with the applied loading. In this study, an inelastic constitutive equation for the ceramic thermal barrier coatings deposited by APS is developed. The obtained results are as follows: (1) the micromechanics-based constitutive equation was formulated with micro crack density formed at splat boundary, and (2) it was shown that the numerical results for a nonlinearly deformed beam simulated by the developed constitutive equation agreed with the experimental results obtained by cantilever bending tests.  相似文献   
6.
Polyimide foam (PF) is a low-thermal conductivity and lightweight material with high resistances against heat, protons, and UV irradiation. A new thermal insulation composed of PFs and multiple aluminized films (PF–MLI) has potential to be used in outer space as an alternative to conventional multilayer insulation (MLI). As fundamental numerical data, the effective thermal conductivity of PF in wide ranges of density and temperature need to be determined. In the present study, thermal-conductivity measurements were performed by both the periodic heating method and the guarded hot-plate method in the temperature range from 160 K to 370 K and the density range from 6.67  \(\mathrm{kg} \cdot \mathrm{m}^{-3}\) to 242.63  \(\mathrm{kg}\cdot \mathrm{m}^{-3}\) . The experiments were carried out in a vacuum and under atmospheric pressure. For confirmation of the validity of the present guarded hot-plate apparatus under atmospheric pressure, the effective thermal conductivity of the lowest-density PF was measured with the aid of the heat flow meter apparatus calibrated by the standard reference material (NIST SRM 1450c) in the temperature range from 303 K to 323 K. In order to cross-check the present experimental results, the temperature and density dependences of the effective thermal conductivity of PF were estimated by means of the lattice Boltzmann method based on a dodecahedron inner microscopic complex structure model which reflects a real 3D X-ray CT image of PF.  相似文献   
7.
Vascular calcification is associated with a poor prognosis in dialysis patients. It can be assessed with computed tomography but simple inoffice techniques may provide useful information. We compared the results obtained with a simple noninvasive technique with those obtained using multidetector computed tomography for aortic arch calcification volume (AoACV) in chronic hemodialysis (HD) patients. The enrolled study subjects were 63 (32 men and 31 women) maintenance HD patients. Calcification of the aortic arch was semiquantitatively estimated with a AoAC score (AoACS) on plain chest radiology. The AoACV was increased, with a mean value of 6.6 ranging from 0% to 36.5%. The coefficient of intraobserver variation was less than 2.5%. Aortic arch calcification score was highly correlated with AoACV (r=0.635, P<0.001). Multiple regression analysis showed age (F value=12.62, P<0.001) and pulse pressure (F value=4.54, P=0.037) to be significant independent determinants of AoACS. In conclusion, a simple measurement of AoACS may be useful for inoffice imaging to choose a therapeutic regimen in HD patients.  相似文献   
8.
Static corrosion tests were performed in molten salts, LiF–BeF2 (Flibe) and LiF–NaF–KF (Flinak), at 500 °C and 600 °C for 1000 h. The purpose is to investigate the corrosion characteristics of reduced activation ferritic steels, JLF-1 (8.92Cr–2W) in the fluids. The concentration of hydrogen fluoride (HF) in the fluids was measured by slurry pH titration method before and after the exposure. The HF concentration determined the fluoridation potential. The corrosion was mainly caused by dissolution of Fe and Cr into the fluids due to fluoridation and/or electrochemical corrosion. Carbon on the surface might be dissolved into the fluids due to the corrosion, and this resulted to the decrease of carbide on the surface. The corrosion depth of the JLF-1 specimen, which was obtained from the weight losses, was 0.637 μm in Flibe at 600 °C and 6.73 μm in Flinak at 600 °C.  相似文献   
9.
Thermal cis–trans conversion has been examined in oligothiophene single molecules encapsulated in the molecular vessels of cyclodextrin and Na-mordenite. At high temperatures, optical absorption intensities are enhanced in bithiophene, terthiophene and quinquethiophene, while the intensity of quarterthiophene is temperature independent. Optical absorption comes from uncompensated transition dipole moment due to the thermal torsion between cis and trans forms.  相似文献   
10.
This paper presents a novel methodology for Maximum Power Point Tracking (MPPT) of a grid-connected 20 kW photovoltaic (PV) system using neuro-fuzzy network. The proposed method predicts the reference PV voltage guarantying optimal power transfer between the PV generator and the main utility grid. The neuro-fuzzy network is composed of a fuzzy rule-based classifier and three multi-layered feed forwarded Artificial Neural Networks (ANN). Inputs of the network (irradiance and temperature) are classified before they are fed into the appropriated ANN for either training or estimation process while the output is the reference voltage. The main advantage of the proposed methodology, comparing to a conventional single neural network-based approach, is the distinct generalization ability regarding to the nonlinear and dynamic behavior of a PV generator. In fact, the neuro-fuzzy network is a neural network based multi-model machine learning that defines a set of local models emulating the complex and nonlinear behavior of a PV generator under a wide range of operating conditions. Simulation results under several rapid irradiance variations proved that the proposed MPPT method fulfilled the highest efficiency comparing to a conventional single neural network and the Perturb and Observe (P&O) algorithm dispositive.  相似文献   
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