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1.
The stabilities of a commercial diacylglycerol‐rich oil (DAG) and a salad oil (TAG) that had been prepared from a mixture of rapeseed and soybean oils were compared while frying potatoes at 180 °C for 3 h. The representative chemical and physical characteristics of the oils were assessed before and after frying, together with the amount of volatile aldehydes in the exhaust of frying. Among the deterioration indications, the carbonyl value, polymer content, and residual polyunsaturated fatty acid content were similar and not significantly different between the TAG and DAG. On the other hand, the characteristics relating to free fatty acids, i.e. the acid value and emission of chemiluminescence at 100 °C, were greater and the smoke and flash points were lower in the DAG than in the TAG. An irritating odor was generated from the DAG after 1 h of frying and got stronger as frying continued. These results suggested that DAG more easily forms free fatty acids under frying conditions than TAG.  相似文献   
2.
We report herein the unusual case of a 59-year-old woman with Plummer-Vinson syndrome who developed gastric cancer. The patient had a longstanding history of dysphagia and iron deficiency anemia, for which she had sporadically taken iron supplements that improved the dysphagia to some extent, but not completely. Owing to her tolerance of the dysphagia, she had not been taking iron supplements for the past 17 years. On admission, she was in fair nutritional condition and not anemic. Blood chemistry results were all normal, including the serum iron level. Gastrointestinal radiographic series demonstrated cervical esophageal webs and advanced gastric cancer. Her dysphagia was successfully treated by endoscopic bougienage through the webs, and a distal partial gastrectomy with nodal dissection was performed. Histology of the resected stomach revealed atrophic mucosal change and, by chance, an adenomatous lesion in addition to adenocarcinoma. Her postoperative course was uneventful and she is now well, without any signs of recurrence. Although Plummer-Vinson syndrome is known to be associated with upper alimentary tract cancers, gastric cancer is extremely rare. A discussion on the etiology of Plummer-Vinson syndrome and its link with potential carcinogenesis follows this case report.  相似文献   
3.
Notes that a puzzling inconclusiveness has prevailed in the comparison of anticipation and study (reinforcement)-test (RT) procedures in verbal learning. To help to resolve this, the present study elaborated the retention interval hypothesis, applicable to both paired-associate and verbal discrimination learning. Ss were 115 undergraduates. Theoretical and empirical specifications for the effects of the list length (n) factor were supported: n determined the superiority or non-difference for the study-test method compared to the anticipation method. Performance differences between the 2 methods were significant when the list length was intermediate, but were insignificant when it was either too short or too long, where learning was, respectively, either too easy or too difficult. (French summary) (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
BACKGROUND: It is widely accepted that red wines constitute one of the most important sources of dietary polyphenolic antioxidants. However, it is still not known how some variables such as variety, vintage, country of origin, and retail price are associated with the antioxidant activity and sensory profile of South American red wines. In this regard, 80 samples produced in Brazil, Chile and Argentina were assessed in relation to their sensory properties, color and in vitro antioxidant activity, and results were subjected to multivariate statistical techniques. RESULTS: Samples were grouped in clusters, characterized by high, intermediate and low in vitro antioxidant activity, sensory properties and prices. It was possible to observe that wines with high antioxidant activity were associated to high retail prices and overall perception of sensory quality. CONCLUSION: South American wines produced from Vitis vinifera such as Syrah, Malbec and Cabernet Sauvignon had higher in vitro antioxidant activity and also higher sensory quality than wines produced from Vitis labrusca. This result was independent of vintage (2002‐2010), corroborating the idea that the same grape varietal, even when produced in different years, displays similar sensory characteristics and antioxidant activity. Copyright © 2011 Society of Chemical Industry  相似文献   
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6.
The transmission Kossel (TK) technique was applied in an attempt to elucidate the formation of (110) [001] grains in the recrystallized texture of high induction and low core loss grain oriented silicon steel containing a small amount of Mo after an intermediate annealing. Prior to the detailed TK examination, the etch pit technique was also used for seeking the representative areas of (110) [001] grains. The average matrix grain size of an intermediate annealed steel containing a small amount of Mo is slightly smaller than that with no Mo. The formation of (110) [001] grains in the vicinity of the steel surface is also strengthened due to the addition of Mo. The diameters of single (110) [001] grains are comparable to or slightly larger than those of other matrix grains, but those of the colonized (110) [001] grains occupy extremely large areas (about 40 pet at the maximum area). The areal fraction of (110) [001] grains of the intermediate annealed sheets containing a small amount of Mo is approximately 1 to 5 times as large as that with the conventional inhibitors such as MnSe and Sb. The colonies of (110) [001] grains formed during an intermediate annealing are compatible with the volume fraction inherited from small and well-defined (110) [001] areas with the sharpened TK patterns in the hotrolled sheet containing a small amount of Mo. It is believed that the preferential formation of (110) [001] grains during an intermediate annealing is inherited by the structure memory from the original hot-rolled texture, and it is noticeably strengthened with the addition of Mo.  相似文献   
7.
The degradation of several azo dyes by the cell-free extract from Pseudomonas stutzeri has been studied. The compounds 2-carboxy-4′-dimethylaminoazobenzene, 4-carboxy-4′-dimethylaminoazobenzene, 2-carboxy 4′-die thy lam inoazobenzene, 2-met hoxycarbonyl-4′-dime t h y lam inoazobenzene, 4-dime t h y lam inoazobenzene sulphonic acid, and 2-hydroxy-1 -naphthaleneazobenzenesulphonic acid were appreciably degraded by the cell- f ree extract. The cell- f ree extract was quite specific for 2-ca rboxy-4 ′-diet h y lam inoazo benzen e, 2 met hoxyca rbonyI4′-dime t h y lam inoazo benzene, and 2-ca rboxy4′-dime t h y lam inoazo benzene, which a reequal in their redox potential. Thus, it is suggested that the substrate specificity is characterised by a log Pdependence. The presence of azo reductase in the cell-free extract was alsoconfirmed by electrophoresis.  相似文献   
8.
Cholesteryl ester, along with triglyceride (TG), is the major core component of plasma lipoproteins. We investigated the effect of core composition on the physical state and metabolic behavior of lipid emulsions, as model particles of lipoproteins. Fluorescence studies using 1,6-diphenylhexatriene analogs showed that although cholesteryl oleate (CO) significantly decreased core mobility, the surface rigidity of phosphatidylcholine (PC) monolayers was independent of core composition. When intravenously injected into rats, the increased amount of core CO tended to retard TG emulsion removal from plasma, and the initial clearance rate was correlated with the amount of apolipoprotein E (apoE) bound from plasma. In addition, PC liposomes with a similar emulsion particle size showed negligible binding of apoE and were cleared at a slower rate compared to all emulsions. Furthermore, the effect of CO on the binding behavior of apoE to the emulsion surface and the emulsion uptake by hepatocytes was assessed in vitro. Replacing core TG with CO was found to decrease the apoE binding capacity to emulsions markedly without changing the binding affinity and thereby to reduce the cell uptake of emulsion particles by HepG2 cells. These results indicate that the physical state of core lipids, which can be modulated by cO content, plays a role in emulsion metabolism through the alteration in apoE binding.  相似文献   
9.
The purpose of the present work was to evaluate polyvinyl alcohols (PVAs) as a mucoadhesive polymer for mucoadhesive buccal tablets prepared by direct compression. Various polymerization degree and particle diameter PVAs were investigated for their usability. The tensile strength, in vitro adhesive force, and water absorption properties of the tablets were determined to compare the various PVAs. The highest values of the tensile strength and the in vitro adhesive force were observed for PVAs with a medium viscosity and small particle size. The optimal PVA was identified by a factorial design analysis. Mucoadhesive tablets containing the optimal PVA were compared with carboxyvinyl polymer and hydroxypropyl cellulose formulations. The optimal PVA gives a high adhesive force, has a low viscosity, and resulted in relatively rapid drug release. Formulations containing carboxyvinyl polymer had high tensile strengths but short disintegration times. Higher hydroxypropyl cellulose concentration formulations had good adhesion forces and very long disintegration times. We identified the optimal characteristics of PVA, and the usefulness of mucoadhesive buccal tablets containing this PVA was suggested from their formulation properties.  相似文献   
10.
Regularly-structured solid matrices are potent materials for regulating molecular permeation and diffusion. Zeolite materials bearing ordered micropores are very advantageous to control the diffusion of molecules. When some disilylbenzene compounds were grafted on mordenite and ZSM-5 zeolites, the penetrations of small molecules such as α-methylstyrene (AMS) and molecular nitrogen were prevented by the direct formation of the crosslinking with two grafting sites on the exterior surfaces of those zeolites. The dimerization reaction of α-methylstyrene effectively promoted by mordenite was not catalyzed by these grafted mordenite samples. No adsorptions of molecular nitrogen were observed in the grafted mordenite and ZSM-5 samples. When these grafted samples were calcined, both the catalytic activity for the dimerization and the permeation of molecular nitrogen were recovered. The reopening of the micropores of zeolites was also achieved by the treatment with HCl acidic solutions. Thus, the diffusion and the permeation of various small molecules can be perfectly and reversely controlled by the sealing and the reopening of the micropores of zeolites by the disilylbenzene compounds.  相似文献   
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