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991.
ABSTRACT The relationship between pH, ionic strength, and water balance of chicken-breast muscle gels was investigated. An increase in gel pH (pH 6.4 to 7.4) without added NaCl led to dramatic increases in water-holding capacity and water uptake (P < 0.05). Gels at 150 mM NaCl exhibited less ability to adsorb water than salt-free gels (P < 0.05 at pH 6.8 to 7.4) and had lower water-holding capacities (P < 0.05) and fold scores at and below pH 7. Varying salt concentration of the gel-bathing solutions had dramatic effect on the water uptake of the gels. The results show that strong water-absorbing gels can be produced at low ionic strengths and suggest that the negative charge of the muscle proteins is the driving force for water uptake and retention.  相似文献   
992.
993.
The qualitative and quantitative radiochemical composition of liquid wastes is substantiated. This makes possible further safe operation of deep waste disposal sites at the Mining-Chemical Plant and the Siberian Chemical Plant. The toxicity and temperature in a formation with the wastes removed are used as the assessment criteria, satisfaction of which guarantees that the wastes will remain localized within the assigned boundaries of the waste-disposal formation site. It is concluded that the standard limit should be imposed on the specific activity of the long-lived group of radionuclides – 90Sr and 137Cs – rather than on the total specific activity of the wastes placed in deep disposal sites. For maximum specific activity of 90Sr and 137Cs of 37 GBq/dm3 and total specific activity not exceeding 185 GBq/dm3 for buried wastes with radionuclide composition characteristic of modern radiochemical production operations, it is impossible for potentially dangerous radiation and thermochemical processes to occur in the waste-disposal formation site. The recommended limit permits reducing substantially the volume of buried wastes and therefore the region over which the wastes propagate in the deep disposal site.  相似文献   
994.
Electron back-scattering diffraction (EBSD) can be successfully performed on SiC coatings for HTR fuel particles. EBSD grain maps obtained from thick and thin unirradiated samples are presented, along with pole figures showing textures and a chart showing the distribution of grain aspect ratios. This information is of great interest, and contributes to improving the process parameters and ensuring the reproducibility of coatings.  相似文献   
995.
We have demonstrated stable operation of a 2-kW Yb:YAG phase-conjugate master oscillator power amplifier (PC-MOPA) laser system with a loop phase-conjugate mirror (LPCM). This is the first demonstration of a continuous wave (CW)-input LPCM MOPA operating at a power greater than 1 kW with a nearly diffraction-limited output beam. The single-pass beam quality incident on the LPCM varied with the specific operating conditions, but it was typically ~20 times diffraction-limited (XDL). The measured beam quality with an MOPA output power of 1.65 kW was 1.3 XDL.  相似文献   
996.
Advantages and disadvantages of the methods for calculation of magnetic circuits and fields of electromagnets are discussed. Plane-parallel, meridian plane, and 3D problems, as well as manual and computer calculation methods are considered.  相似文献   
997.
The structure and properties of an austenitic high-nitrogen corrosion-resistant 05Kh22AG15N8M2F cast steel produced by high-gradient directional solidification (HGDS) and equiaxed-grain solidification (ES) have been studied and compared. In contrast to ES, HGDS allows one to substantially decrease the degree of dendritic segregation of alloying elements, to eliminate porosity, and to increase the strength and plasticity of the steel.  相似文献   
998.
文中简述了卤化银(主要是溴化银)单晶片的某些特性,氯化银单晶片与此大致相似。作为低温晶体探测器,对~(241)Am-α放射源,分辨率为17%。卤化银晶片是固体电解质,只有Ag离子对输出电信号有贡献,有显著的极化现象。在液氮槽内溴化银晶片的电导率在几个数量级内成为可控的,由在室温下外加偏置电压大小所引起的分解状态下的初始电流决定。  相似文献   
999.
1000.
Rats of four groups each holding 6-8 animals were changed over to intragastric nutrition with different mixtures one week after cannula implantation into the stomach. The observation period constituted 15 days. The rats of two other groups were kept on oral feeding with a common diet. As compared to oral feeding, intragastric one led to alterations in the cecum microflora. More profound hydrolysis of the nutrients contained by the mixture produced a more demonstrable increase in the number of enterobacteria, enterococci, staphylococci, and lactobacilli. Intragastric feeding with a mixture without nitrogenous component sharply reduced the number of lactobacilli in the cecum contents.  相似文献   
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