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121.
In the present work, evolution of damage under high‐temperature (823 K) low cycle fatigue loading condition in near α IMI‐834 titanium alloy has been studied. The in situ damage has been experimentally measured during cyclic deformation using the alternating current potential drop (ACPD) technique. The measured damage curve has been compared with the damage curves calculated through mechanical variables such as cyclic modulus and stress amplitude. The ACPD damage curve has been found most sensitive towards high‐temperature low cycle fatigue damage evolution.  相似文献   
122.
In the present study, the vorticity of melt motion in the keyhole and weld pool has been evaluated in case of high power CO2 laser beam welding. The circulation of vorticity is obtained as a function of Reynolds number for a given keyhole volume which is linked to Mach number variation. The shear stress and thermal fluxes present in the turbulent pool are linked to diffusivity and Prandtl number variation. It was shown that below a critical value of Rayleigh number, the conduction mode of melt transfer signifying beam absorption becomes dominant. Above this value, convective heat transfer indicates melting and evaporation occurring in the weld pool during laser welding. The evaporative recoil pressure expels the liquid while surface tension and hydrostatic pressure help to retain the melt in the keyhole cavity in this high power laser beam welding. The understanding of several hydrodynamic phenomena occuring in the weld pool is valuable not only for understanding basic mechanistic aspects but also for process optimization involved in laser beam welding.  相似文献   
123.
The effects of cheese age when packaged and of packaging material permeability on Manchego cheese characteristics were studied throughout a 6-month ripening period. Cheese age when packaged had no significant effect on microbial levels, proteolysis, lipolysis or flavor. However, moisture content and rheological characteristics were significantly different for cheeses packaged 1, 2 or 3 wk after salting. Packaging material had no influence on microbiological, chemical, rheological or sensory characteristics of Manchego cheese. Packaged cheese had a lower flavor intensity than nonpackaged cheese, but no significant differences in flavor quality between packaged and non-packaged cheese were recorded. Weight losses after 6 months were undetectable in packaged cheese, but they averaged 15.16% in non-packaged cheese.  相似文献   
124.
The antimicrobial activity of petroleum ether, benzene, chloroform, ethyl acetate and methanol extracts of Decalepis hamiltonii Wight and Arn. (Asclepiadaceae) against 15 different food‐related microorganisms was evaluated. Among the solvent extracts, methanolic and petroleum ether extracts are the most active exhibiting growth inhibition of 11 and nine of the 15 organisms, respectively. The inhibitory activity was comparable with the respective standards. The results suggest that methanolic and petroleum ether extracts can be used for the bioactivity‐guided isolation of novel antimicrobials which prevents food spoilage.  相似文献   
125.
126.
The performance and bio‐kinetic coefficients of the activated sludge process (ASP) treating synthesised dairy wastewater were evaluated in a lab‐scale setup. The step‐loading experiment showed that the chemical oxygen demand (COD) removal efficiency, in general, increased with increasing influent wastewater COD concentration from 180 to 1200 mg/L (correlation coefficient was 0.80). The COD removal efficiency ranged from almost 80–88.4% depending on the COD concentration of the influent wastewater. Also, it could be stated that the ASP was probably underfed with organics at COD concentrations <725 mg/L. Monod, Moser, Contois and Chen & Hashimoto substrate utilisation models, relating the growth of micro‐organisms to substrate utilisation, were employed to describe the bio‐kinetics of the ASP at an organic loading rate of 1200 mg/L. Amongst them, the Contois and Monod models predicted the bio‐kinetic reactions of the ASP very well with coefficient of determination (R2) values of 0.95 and 0.93, respectively. The estimated bio‐kinetic coefficients of the Contois model (on COD basis) were as follows: half‐velocity constant (0.20 mg/L), maximum substrate utilisation rate (3.13 per day), biomass yield coefficient (0.68), endogenous decay coefficient (0.07 per day) and maximum specific growth rate (2.13 per day).  相似文献   
127.
DASHA 《核技术(英文版)》2000,11(3):167-172
Predictions on the leaching behaviour of microconstituents from dumped,stored,or immobilised wastes are based on estimates of the effective diffusion coefficients involoed,which usually range from -10^-6 to -10^-12 cm^2.s^-1,Radioanalysis,especially radiotracer procedures,can be applied to determine these parameters on small (field) samples of granular material and test specimens of immobilised wastes. A summary of standard experiments for both types of material under non-steady state and steady state conditions is presented.  相似文献   
128.
Phyllanthus emblica or Indian gooseberry is an integrated part of Ayurvedic and Traditional Chinese Medicines. For several decades, the well-known ancient herb has been extensively utilized in traditional medicine to cure diseases like fever, diabetes, constipation, jaundice, ulcers, biliousness, anemia, anorexia, and dyspepsia. In the traditional system, Indian gooseberry has various ethnomedicinal applications. In the Ayurvedic system, different methods of administration (anupan) have shown different ethnomedicinal properties of Indian gooseberry. Seventy well-known chemical components in Indian gooseberry have been identified through phytochemical evaluation, among which the flavonoids and phenols are most prominent. From the toxicity perspective, it is considered a safe herb in India, and is taken as a food supplement in European countries. The wide-spectrum pharmacological activities of the crude extracts and isolates of Indian gooseberry are attributed to the predominance of phenols and flavonoids. Thus, it is important to study the exact mechanism of the activity of the phytochemicals in Indian gooseberry, especially in anti-cancer activities. Extract of Indian gooseberry enhances proliferation in several cancer cells in vitro, including stem cells like ovarian cancer (OC) cells, and also has been observed to possess anti-proliferative characteristics in vivo. This review intends to explore the therapeutic potential of Indian gooseberry based on scientific reports and attempts to find the gaps for future research.  相似文献   
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