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51.
ABSTRACT The biaxial fatigue of a steel plate (JIS SM400B) having a box‐welded (wrap‐around) joint was experimentally studied. Special concerns were focused on the effects of the biaxial load range ratio and compressive cyclic loading in the lateral direction. The direction of fatigue crack propagation under biaxial cyclic tensile loading, which has a phase difference of π, changed according to the biaxial load range ratio, Rxy = ΔPxPy. When Rxy was less than 0.56, fatigue cracks propagated along the toe of the weld in the x‐direction because the principal tensile stress range Δσy at that location exceeded the orthogonal value Δσx at the box‐weld toe. The fatigue lives in biaxial tests related well to the data from uniaxial tests when invoking the Δσ5 criterion. However, the location and direction of Δσ5 should be chosen according to the Rxy value and the failure crack direction. An increase in Δσ5, as induced by the Poisson's ratio effect from either the out‐of‐phase tensile loading or the in‐phase compressive loading in the y‐direction, leads to an increase in fatigue damage (decrease in fatigue resistance or specifically a faster crack propagation rate), and this effect can be successfully estimated from uniaxial fatigue test data.  相似文献   
52.
A new process was developed to regulate the papain-induced overtenderization of meat by using oryzacystatin, a cysteine proteinase inhibitor of rice seed origin. Meat cubes (2 × 2 × 2 cm each), aged 3 days, were treated with a 0.1 fold weight of papain solution and incubated at 8°C. The most favorable degree of tenderization resulted when a 2% papain solution was used for 2 h at 8°C. When the incubation was made for 24 h or longer, overtenderization resulted. The incubation of a meat cube with papain for the first 2 h and then with an adequate amount of added oryzacystatin for the subsequent 22 h was effective in regulating overtenderization. It was also confirmed by SDS-polyacrylamide gel electro-phoresis that the use of oryzacystatin under similar incubation conditions regulated the papain-aided hydrolysis of myofibrillar proteins.  相似文献   
53.
A pulsed electric field(PEF) was applied to unpasteurized sake at constant temperatures, at which α-amylase was not inactivated. We adjusted the input energy to be identical for the temperatures by changing the number of PEF application, because the current significantly increased with the temperature, even the amplitude of the applied voltage was identical. As a result, the α-amylase was seemed to be inactivated by PEF application, not due to thermal effect.The glucoamylase was significantly inactivated by PEF. Moreover, the acid carboxypeptidase was inactivated by PEF at 4 °C but significantly activated at 25 °C. These results show that the sensitivity of enzyme to PEF application differs depending on the types of enzyme and treatment temperature. On the other hand, the colony number of bacteria was remarkably decreased, but the amount of the volatile flavor compounds was not decreased by PEF application.  相似文献   
54.
Strains of S. thermophilus grown on partially deproteinized whey produced an exocellular polysaccharide which contained L-rhamnose and D-galactose in the ratio 1:1.47. Methylation analysis showed the existence of 3 and 6-substituted D-galactose, 2-substituted L-rhamnose and nonreducing terminal D-galactose. A polysaccharide was also obtained from the cell surface after sonication. Molecular weights of both polysaccharides were estimated by gel filtration on HPLC at about 9,000,000 and 1,100,000, respectively. These polysaccharides were different from the previously reported products by S. thermophilus strains and their presence may contribute to the ropy property of yogurt.  相似文献   
55.
To realize an excitation of electron Bernstein waves (EBW) via mode conversion from X-mode waves injected from the high magnetic field side (HFS), new inner-vessel mirrors were installed close to a helical coil in the large helical device (LHD). 77 GHz electron cyclotron (EC) wave beams injected from an existing EC-wave injection system toward the new mirror are reflected on the mirror so that the beams are injected to plasmas from HFS. Evident increases in the electron temperature at the plasma core region and the plasma stored energy were observed by the HFS beam injection to the plasmas with the line-average electron density of 7.5×10 19 m 3 , which is slightly higher than the plasma cut-off density of 77 GHz EC-waves, 7.35×10 19 m 3 . The heating efficiency evaluated from the changes in the time derivative of the plasma stored energy reached ~70%. Although so far it is not clear which is the main cause of the heating effect, the mode-converted EBW or the X-mode wave itself injected from the HFS, an effective heating of high-density plasma over the plasma cut-off of EC-wave was successfully demonstrated.  相似文献   
56.
57.
Multi‐emitter fitting algorithms have been developed to improve the temporal resolution of single‐molecule switching nanoscopy, but the molecular density range they can analyse is narrow and the computation required is intensive, significantly limiting their practical application. Here, we propose a computationally fast method, wedged template matching (WTM), an algorithm that uses a template matching technique to localise molecules at any overlapping molecular density from sparse to ultrahigh density with subdiffraction resolution. WTM achieves the localization of overlapping molecules at densities up to 600 molecules μm–2 with a high detection sensitivity and fast computational speed. WTM also shows localization precision comparable with that of DAOSTORM (an algorithm for high‐density super‐resolution microscopy), at densities up to 20 molecules μm–2, and better than DAOSTORM at higher molecular densities. The application of WTM to a high‐density biological sample image demonstrated that it resolved protein dynamics from live cell images with subdiffraction resolution and a temporal resolution of several hundred milliseconds or less through a significant reduction in the number of camera images required for a high‐density reconstruction. WTM algorithm is a computationally fast, multi‐emitter fitting algorithm that can analyse over a wide range of molecular densities. The algorithm is available through the website. https://doi.org/10.17632/bf3z6xpn5j.1  相似文献   
58.
胡本芙  吴承健 《金属学报》1995,31(11):525-530
研制了一种具有低肿用蒿强度的氧化物弥散强化型铁素体钢Fe-Cr-W-Ti-Y2O3,并对其抗辐照损伤行为进行了系统研究。电子辐照表明,Y2O3弥散氧化物质点在所研究的辐照下是稳定的,在辐过程中形成b=a〈100〉和b=a/2〈111〉两种类型的位错环。  相似文献   
59.
In this paper, a cooperative control algorithm for multiple step voltage regulator (SVR) using correlation of measurement data of distribution line is proposed. Conventionally, the control time constant of a SVR placed on the feeder end side was set slower than a SVR placed on the substation side. The unnecessary tap movement of SVR was reduced by this setting. In this case, on the condition that “the photovoltaic power generation output of the feeder end fluctuates” and “only SVR of the end side works”, it is a problem that control of SVR becomes slow. By the proposed method, the SVR settled in end side of a feeder can change its tap rapidly only if the SVR settled in sending side of a feeder will not change its tap by using proposed method. The features of the method are followings: (1) to estimate tap change possibility of the sending side SVR using correlation model of both of the SVR, (2) only use local measurement data of the SVRs for tap change control. By the proposed method, unnecessary tap change operation and lag of tap control are reduced without communication networks.  相似文献   
60.
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