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排序方式: 共有880条查询结果,搜索用时 31 毫秒
81.
82.
S. A. Allison L. A. Goold M. J. Nicol A. Granville 《Metallurgical and Materials Transactions B》1972,3(10):2613-2618
The surface reaction products formed when sulfide minerals react with xanthates were analyzed by spectrophotometric methods.
These products were found to be predominantly either metal xanthate or dixanthogen, depending on the particular sulfide mineral.
Dixanthogen is formed on those minerals that, in a solution of xanthate, assume a rest potential greater than the equilibrium
potential for the reduction of dixanthogen or xanthate. 相似文献
83.
From the Rorschach findings presented, it can be inferred that "transorbital lobotomy results in a lessening of inner tension, a lessening of introspective self-awareness and insight, and a loss of ardent enthusiasm and active interest." A significant increase in W% is interpreted as some change in apperception. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Summary p-Aminobenzoylcaprolactam has been polymerized anionically in a two-step process to produce aramide-amide copolymers. Both drawn fibers and unoriented films may be produced using this method. The samples were characterized using FTIR, solution NMR, thermal analysis, viscosity, and mechanical testing. FTIR and NMR revealed the incorporation of both the aramid and amide linkages into the polymer backbone. TGA results gave a lower decomposition temperature than that of both aramide and nylon 6 materials. Intrinsic viscosities averaged 0.5 dL/g for the drawn copolymer samples polymerized by the di-functional initiator. Light microscopy displayed crystalline domains that did not appear to melt even up to 300°C. Mechanical testing showed that the initial moduli of drawn fiber samples to be in the range of 30–80 MPa, while homopolymers of nylon 6 and p-benzamide possessed values of 25 MPa and 2.70×103 MPa, respectively. 相似文献
86.
Michael J. Allison 《Journal of the science of food and agriculture》1983,34(2):175-180
A Neotec Scanning Infrared Analyser was used to generate predictive equations for the rapid estimation of kale digestibility. The most successful of these equations gave estimates of digestibility of samples in a calibration population that correlated highly (r=0.95) with the manual estimates. When this method was applied to additional kale samples, not included in the calibration set, it was again successful in screening for high digestibility, despite lower correlation coefficients and increases in standard errors as compared to the equivalent results for the calibration set. Absorption peaks in the spectral scans of cell wall components were compared with the wavelengths used in the best prediction equation in an attempt to gain a clearer understanding of the factor or factors that limit kale digestibility. 相似文献
87.
The effects of zinc sulphate pretreatment on the formation of gastric ulcers, changes in intragastric pressure and changes in the gastric mucosal mast cell count induced by electrical vagal stimulation were studied in anaesthetized rats. Vagal stimulation produced a high gastric glandular ulcer incidence and ulcer index, increased the intragastric pressure, and reduced the number of granulated mast cells in the gastric mucosa and submucosa. Pretreatment with zinc sulphate (22, 44 ot 88 mg/kg), injected i.p. 48 h beforehand, reversed the changes in these parameters in a dose-related manner. These observations suggest that the inhibitory effects of zinc sulphate on mucosal mast cell degranulation may account for its ability to antagonise vagal-induced gastric glandular ulceration. The mechanisms involved in the aetiology of this type of gastric ulcer are discussed in the light of these results. 相似文献
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