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91.
曹长娥 《焊管》1997,20(6):57-61
试验了彩色聚乙烯涂覆钢管的耐腐蚀性和耐气候性,由于聚乙烯涂层隔绝水的作用,聚乙烯涂覆钢管具有优良的耐腐蚀性能,电阻绝缘值和优良的机械性能。建立了一个新的方式去研究分析聚乙烯抗老化剂消耗和在聚乙烯中的扩散。用有效测定的方法定量地预测彩色聚乙烯涂覆层的寿命,应用这些分析结果,不仅可使新的有色聚乙烯涂覆钢管在恶劣腐蚀环境介质情况下具有高的耐腐蚀性,而且有长的耐气候性。  相似文献   
92.
The Film Dryout Analysis Code in Subchannels, FIDAS, has been developed with the main objective of predicting dryout and post-dryout heat transfer in a channel and in rod bundles. In FIDAS, two-phase flow consisting of continuous liquid film, continuous vapor and entrained droplets is modeled by a three-fluid, three-field representation of 12 field equations, i.e. three continuity, three energy and six momentum equations. FIDAS can predict dryout without any empirical CHF correlations by introducing annular flow modeling and the ‘film dryout criterion’. Experiments on film flow characteristics, subchannel flow and enthalpy distributions, dryout and post-dryout heat transfer in tubes and rod bundles were analyzed to demonstrate the performance of FIDAS. The predictions of FIDAS are in close agreement with the experiments.  相似文献   
93.
A new scheme named the Traveling Load Test is proposed to measure the macroscopic deformation modulus of the floor rock mass in an open pit, covering a volume of rock mass much larger than conventional loading tests. Facility of the test includes extra-large excavators as load-sources on the flat surface and high-resolution borehole tilt-meters installed in rock to detect the microscopic tilt induced by the load. Emphasis is given to the theory of deformation modulus determination, which is applicable to the field where the floor is fully covered by an accumulation of loose blocks of stone produced by blasting damage and/or stress relief. The relation between the induced tilt and the traveling load is formulated, and subsequently it is shown how the deformation modulus is determined by analyzing the induced tilt-loading distance curve, within acceptable engineering accuracy.  相似文献   
94.
95.
(Sr1-xPbx)TiO3 (SPT) ceramics have low loss tangents and high dielectric tunabilities under DC bias fields at room temperature, but they have the disadvantage of high dielectric constants. In order to exploit these materials for microwave applications, the reduction of dielectric permittivities is necessary. Thus, the composites of the SPT system by the addition of a non-ferroelectric oxide such as MgO were prepared and electrical properties were measured. Loss tangents of the composite sintered at the same temperature as SPT's sintering were less than 0.3% in paraelectric region just above the transition temperature and the dielectric tunabilities of ~20% at 20 kV/cm and ~35% at 40 kV/cm were observed at 10 kHz.  相似文献   
96.
The antitumor effects of toremifene were studied in vitro using 10 anaplastic thyroid carcinoma cell lines and were compared with those of tamoxifen. The antitumor effect of toremifene was dose-dependent and the IC50 values for these cell lines ranged 20.1-58.5 microM. Although the cell lines expressed multidrug resistance gene mRNA, multidrug resistance-associated protein gene mRNA and insulin-like growth factor-1 (IGF-1) receptor mRNA to various degrees, nine of them lacked estrogen receptor expression as evaluated by immunocytochemistry. These data indicate that toremifene, as well as tamoxifen, is cytolytic at relatively high doses for multidrug-resistant anaplastic thyroid carcinoma cell lines.  相似文献   
97.
TAR DNA binding protein 43 (TDP-43) is a DNA/RNA binding protein involved in pivotal cellular functions, especially in RNA metabolism. Hyperphosphorylated and ubiquitinated TDP-43-positive neuronal cytoplasmic inclusions are identified in the brain and spinal cord in most cases of amyotrophic lateral sclerosis (ALS) and a substantial proportion of frontotemporal lobar degeneration (FTLD) cases. TDP-43 dysfunctions and cytoplasmic aggregation seem to be the central pathogenicity in ALS and FTLD. Therefore, unraveling both the physiological and pathological mechanisms of TDP-43 may enable the exploration of novel therapeutic strategies. This review highlights the current understanding of TDP-43 biology and pathology, describing the cellular processes involved in the pathogeneses of ALS and FTLD, such as post-translational modifications, RNA metabolism, liquid–liquid phase separation, proteolysis, and the potential prion-like propagation propensity of the TDP-43 inclusions.  相似文献   
98.
A few authors have reasonably proposed that liquid–liquid phase-separated (LLPS) glasses could show improved fracture strength, Sf, and toughness, KIc, as the second phase could provide a barrier to crack propagation via deflection, bowing, trapping, or bridging. Due to the associated tensile or compressive residual stresses, the second phase could also act as a toughening or a weakening mechanism. In this work, we investigated five glasses of the PbO–B2O3–Al2O3 system spanning across the miscibility gap: Four of them undergo LLPS—three are binodal (two B2O3-rich and one PbO-rich) and one is spinodal—and one does not show LLPS (composition outside the miscibility gap). Their compositions were designed in such a way that the amorphous particles are under compressive residual stresses in some and under tensile residual stresses in others. The following mechanical properties were determined: the Vickers hardness, ball on three balls (B3B) strength, and toughness, KIc-SEVNB (single-edge V-notch beam [SEVNB]). The microstructures and compositions were analyzed using scanning electron microscopy with energy-dispersive X-ray spectrometry. The spinodal glass showed, by far, the best mechanical properties. Its KIc-SEVNB = 1.6 ± 0.1 MPa m1/2, which embodies an increase of almost 50% over the B2O3-rich binodal composition, and 90% considering the PbO-rich binodal composition. Moreover, its fracture strength, Sf = 166 ± 7 MPa, is one of the highest ones ever reported for an LLPS glass. Fracture analyses evidenced that the spinodal composition exhibited the lowest net stress at the fracture point. Moreover, calculations indicate that the internal residual stress level is the lowest in the spinodal glass. The overall results indicate that the microstructural effect of the spinodal glass is the most significant factor for its superior mechanical properties. This work corroborates the idea that LLPS provides a feasible and stimulating solution to improve the mechanical properties of glasses.  相似文献   
99.
    
Pareidolia is a psychological tendency of perceiving a face in non-face stimulus. As a majority of people globally experience this tendency, it has been extensively studied and measured in terms of tendencies, such as frequencies. However, no study has investigated the systematic manipulation of stimulus owing to the lack of a systematic image-generation method. Therefore, herein, we generated face pareidolia stimuli using a face data set with annotated data. We employed cycle-consistent adversarial networks (CycleGAN), an image-to-image-style translation framework, to generate stimuli for translating natural-image styles from face images. We manipulated the weight of the cycle-consistency loss in the CycleGAN via an experiment to evaluate the image generated using the CycleGAN. Thus, we found that the weight value of the evaluation experiment correlated with the pareidolia-inducing power when the preprocessing of the face data set was applied to the blur process. As a result, we achieved to systematically generate pareidolia stimuli. © 2024 The Authors. IEEJ Transactions on Electrical and Electronic Engineering published by Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.  相似文献   
100.
    
It is important to match the feeding ratio of comonomers to the composition ratio in the resulting copolymers as closely as possible in industrial production, where the goal is often to produce more a homogeneous composition in copolymers. In this study, a flow copolymerization system with a conventionally initiated free radical method, together with randomly selected polymerization conditions is investigated. It is succeeded in achieving a closer match between the composition ratio and feeding ratio than previously reported in the copolymerization of styrene with methyl methacrylate and of glycidyl methacrylate with methyl methacrylate, which will widen the range of applications, by precisely controlling the mixing and heating in a flow polymerization apparatus. This is confirmed by the fact that the estimated values of reactivity ratios, r1 and r2, which are used in the reaction kinetics of copolymerization, are close to 1.  相似文献   
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