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71.
In vitro and in vivo efficacy data indicate that chemical activity is optimized at the 2 carbon chain length and that these compounds have injectable potency and spectrum of activity against major animal external parasite species. 相似文献
72.
The Modified Fischer Assay is the accepted method for evaluating the potential liquid fuel yield of an oil shale. For a given shale, percent of Fischer Assay oil yield has become the standard used for judging technologies. The method has been developed for and is well understood when applied to oil shales in the western United States. However, the assay can be successfully applied to eastern United States oil shales only if care is taken in several areas that prove less important for its successful application to western shales. In particular, standardized sample preparation and handling with minimum air exposure of pulverized shale is required; a well-controlled and reproducible heating profile during retorting must be employed; and consistently effective liquid product collection must be accomplished. These considerations have a major influence on assay accuracy. Only with care in these areas, can Modified Fischer Assays suitable for eastern shale resource evaluations and technology comparisons be obtained. 相似文献
73.
DL Wassom DA Loegering GO Solley SB Moore RT Schooley AS Fauci GJ Gleich 《Canadian Metallurgical Quarterly》1981,67(3):651-661
A radioimmunoassay was established for the human eosinophil granule major basic protein (MBP). The mean level of MBP in sera from 105 normal control patients was 454 ng/ml, whereas in a sample of 188 patients with various forms of diseases, including the hypereosinophilic syndrome, levels as high as 14,000 ng/ml were measured. Serum levels of MBP did not correlate with eosinophil counts in normal subjects, but a positive correlation was seen in patients with eosinophilia; the patients with eosinophil counts greater than 350/mm3 generally showed increased levels of MBP. Many patients with skin disease and normal eosinophil counts had elevated levels of serum MBP. Monomer MBP has a molecular weight of 9,300, but in sera of patients with eosinophilia, the MBP activity was of high molecular weight, greater than 50,000. Analyses of serum by Sephadex G-200 and by electrofocusing suggest that MBP is not simply polymerized, but rather is bound to a larger carrier molecule. Monomeric MBP can be isolated from serum by reduction of serum with dithiothreitol, alkylation with iodoacetamide, and acidification to pH 2 followed by fractionation on Sephadex G-50 at pH 2. Under these conditions, up to 80% of the MBP emerges in monomeric form. The results indicate that eosinophil granule proteins circulate in blood covalently bound to serum proteins, and that elevated concentrations of serum MBP are present in some diseases associated with eosinophilia. 相似文献
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77.
Out of 1300 eyes enucleated between 1966-1974, 300 subsequently revealed histologically-proved malignant melanomas of the uvea. In 264 cases the clinical diagnosis was correctly made. In 36 cases the i.o. malignant melanomas were clinically unsuspected. The incorrect clinical diagnoses included: secondary glaucoma (30), retinal detachment (2), iritis (2), and end/panophthalmitis (2). The clinical symptomatology and morphology of the secondary glaucoma caused by the i.o. melanomas did not differ from that due to other, non-neoplastic etiologies. In almost all of the 36 cases the eyes revealed unilateral severe opacity of the media. It is important that one consider an intraocular melanoma in cases of secondary glaucoma, retinal detachment, or intraocular inflammation in which the etiology is uncertain. This is also true in cases of blind, painful eyes in which there is no obvious etiology. Early diagnosis is of vital interest to the patient because this group, in which the malignant melanoma was unsuspected, may be, as suspected in this study, is characterised by extreme aggressivness and invasive capacity. One third of these eyes revealed extension of tumor through the sclera and optic nerve. Also these tumors often revealed more malignant cell types. 相似文献
78.
The time course and mechanism of vulnerability to ventricular fibrillation (VF) a 10-minute occlusion of the left anterior descending coronary artery and following its release were studied in 48 dogs. VF threshold was determined by inducing a sequence of three extrasystoles (sequential R/T pulsing). Within 1 minute of occlusion, the fibrillation current decreased to the level required for eliciting a propagated diastolic response. This state of enhanced vulnerability lasted for approximately 6 minutes, after which the VF threshold returned to preocclusion values. The vulnerability changes upon reperfusion, by comparison, occurred within seconds of release and persisted only transiently. Three minutes of occlusion was the minimal time which resulted in a reduction in VF threshold after release. Alpha and beta-adrenergic blockade with phentolamine and propranolol, respectively, prevented the decrease in VF threshold during occlusion but were without effect upon threshold changes during coronary artery release. Lidocaine failed to alter the pattern of vulnerability. It is concluded that adrenergic mechanisms play a key role in the increased susceptibility to VF associated with acute myocardial ischemia, whereas the changes in VF threshold following reperfusion may be due to washout products of cellular ischemia. These findings support the view that protection against VF during coronary artery occlusion and release may require different antiarrhythmic measures. 相似文献
79.
Chakravarty R Shukla R Ram R Venkatesh M Tyagi AK Dash A 《Analytical chemistry》2011,83(16):6342-6348
The (188)W/(188)Re generator using an acidic alumina column for chromatographic separation of (188)Re has remained the most popular procedure world over. The capacity of bulk alumina for taking up tungstate ions is limited (~50 mg W/g) necessitating the use of very high specific activity (188)W (185-370 GBq/g), which can be produced only in very few high flux reactors available in the world. In this context, the use of high-capacity sorbents would not only mitigate the requirement of high specific activity (188)W but also facilitate easy access to (188)Re. A solid state mechanochemical approach to synthesize nanocrystalline γ-Al(2)O(3) possessing very high W-sorption capacity (500 mg W/g) was developed. The structural and other investigations of the material were carried out using X-ray diffraction (XRD), transmission electron microscopy (TEM), Brunauer Emmett Teller (BET) surface area analysis, thermogravimetric-differential thermal analysis (TG-DTA), and dynamic light scattering (DLS) techniques. The synthesized material had an average crystallite size of ~5 nm and surface area of 252 ± 10 m(2)/g. Sorption characteristics such as distribution ratios (K(d)), capacity, breakthrough profile, and elution behavior were investigated to ensure quantitative uptake of (188)W and selective elution of (188)Re. A 11.1 GBq (300 mCi) (188)W/(188)Re generator was developed using nanocrystalline γ-Al(2)O(3), and its performance was evaluated for a period of 6 months. The overall yield of (188)Re was >80%, with >99.999% radionuclidic purity and >99% radiochemical purity. The eluted (188)Re possessed appreciably high radioactive concentration and was compatible for the preparation of (188)Re labeled radiopharmaceuticals. 相似文献
80.
Ibrahim RM Benesi Maryke T Labuschagne Alfred GO Dixon Nzola M Mahungu 《Journal of the science of food and agriculture》2004,84(11):1381-1388
Cassava is an important food and cash crop in Malawi. It is also becoming increasingly important for industrial use. The aim of this study was to investigate the native starch quality of different Malawi cassava genotypes. Trials were conducted at Chitedze and Makoka in Malawi in the 2000/01 season. Apart from root dry matter and starch extraction, starch quality parameters considered included protein, moisture and ash contents, pH and whiteness. Various stability measures were used to deal with the problem of genotype × environment interaction. The results showed that all the cassava genotypes produced starch with no protein and with colour as white as required by the industry. Moisture and ash contents and pH fell within the industry‐recommended ranges. This suggests that native cassava starch is suitable for use in various industries. Additive main effects and multiplicative interaction (AMMI) was strongly correlated with other measured stability parameters and is therefore recommended for stability analysis of starch quality parameters. Genotype had a larger influence than environment on root dry matter. This agrees with the hypothesis that one or a few major genes control root dry matter in cassava. Copyright © 2004 Society of Chemical Industry 相似文献