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排序方式: 共有937条查询结果,搜索用时 15 毫秒
51.
52.
Wieslaw J. Bochenek Peter Weber Regina Slowinska Gexin Tang John B. Rodgers 《Lipids》1990,25(10):665-668
Monosaccharide composition was determined in apolipoprotein B-48 (apoB) of chylomicrons of rat mesenteric lymph. Chylomicrons
were separated into three fractions based on density. Triglyceride and apolipoprotein content were determined in each. ApoB
was isolated and quantified using precipitation with isopropanol. Chylomicrons were collected in lymph under normal conditions,
and with Poloxalene 2930 when chylomicron secretion was inhibited. Most of the triglyceride was carried in the least dense
fraction, while the highest apoB content was in the most dense fraction under normal conditions. Mannose and galactosamine
contents of apoB were similar in all fractions while contents of both glucosamine and galactose were highest in the least
dense fraction. When chylomicron secretion was inhibited by Poloxalene, the amount of triglyceride recovered in the least
dense fraction was significantly reduced. Despite the inhibition of lipid transport in the least dense fraction of chylomicrons
by Poloxalene, there was little change in apoB recoveries and in the relative content of various monosaccharides in the apoB
from each of the three fractions as compared to results obtained during lipid absorption under normal conditions. In conclusion,
carbohydrate composition of apoB of chylomicrons is heterogeneous and varies with chylomicron density. 相似文献
53.
54.
McHale James P.; Kuersten-Hogan Regina; Lauretti Allison; Rasmussen Jeffrey L. 《Canadian Metallurgical Quarterly》2000,14(2):220
Fifty-two married partners played with their 30-mo-olds in both dyadic (parent–child) and whole family contexts and reported on their own coparenting activities (family integrity-promoting behavior, conflict, disparagement, and reprimand). Coparenting behavior observed in the whole family context was evaluated for antagonism, warmth and cooperation, child–adult centeredness, balance of positive involvement, and management of toddler behavior. Parallel balance and management scores were also formed using dyadic session data. Men's reported family integrity-promoting activities and women's reported conflict and reprimand activities were reliable correlates of family group process in both bivariate and discriminant analyses, with links enduring even after controlling for marital quality. Whole family- and dyad-based estimates of coparenting were altogether unrelated, and reported coparenting was tied only to behavior in family context, not to family measures created from dyad-based data. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Andrea Felgner Regina Schlink Peter Kirschenbühler Birgit Faas Heinz-Dieter Isengard 《Food chemistry》2008
In the field of food analysis, rapid measurements and results are generally of high importance. The Karl Fischer titration (KFT), a chemical method for determining water content, and its automated performance enhance rapidity by giving the opportunity to deal with more samples in less time; automated sequences can include different determination methods and sample treatments. Moreover, automation can improve reproducibility and precision. 相似文献
56.
Functionally Graded Ceramics Fabricated with Side‐by‐Side Tape Casting for Use in Magnetic Refrigeration 下载免费PDF全文
Regina Bulatova Christian Bahl Kjeld Andersen Luise Theil Kuhn Nini Pryds 《International Journal of Applied Ceramic Technology》2015,12(4):891-898
Functionally graded ceramic tapes have been fabricated by a side‐by‐side tape casting technique. This study shows the possibility and describes the main principles of adjacent coflow of slurries resulting in formation of thin plates of graded ceramic material. Results showed that the small variations of solvent and binder system concentrations have a substantial effect on slurry viscosity. Varying these parameters showed that side‐by‐side tape casting with a well‐defined interface area is possible for slurries with viscosities above 3500 mPa s at a casting shear rate of 3.3 s?1. As it was expected, the choice of de‐bindering and sintering regimes significantly influences crack formation, and a three‐step heating programme was found to result in tapes of the highest quality. The interface regions of green graded tapes were investigated structurally by scanning electron microscopy; for a distinct identification of the interface region and analysing the degree of cross‐interface diffusion, the isothermal entropy change was measured by a vibrating sample magnetometer as the magnetic transition temperature (Curie temperature) is very sensitive to the dopant level in ceramics. Also the purpose of developing this graded ceramic tape casting was applications of these specific magnetocaloric properties within the magnetic refrigeration technology. 相似文献
57.
Regina Krachler Rudolf F. Krachler Altan Süphandag Shahram Ayromlou Bernhard K. Keppler 《The Science of the total environment》2010,408(11):2402-9557
Peat bogs have the ability to produce strong chelate ligands (humic and fulvic acids) which enhance the weathering rates of iron-silicate minerals and greatly increase the solubility of the essential trace metal iron in river water. Fluvial networks link peat bogs with the ocean, and thus terrestrial-derived fulvic-iron complexes fuel the ocean's biological productivity and biological carbon pump, but understanding this role is constrained by inconsistent observations regarding the behaviour of riverine iron in the estuarine mixing zone, where precipitation reactions remove iron from the water column. We applied a characterization of the colloidal iron carriers in peatland-draining rivers in North Scotland, using field-flow fractionation (FFF), in combination with end-member mixing experiments of river water sampled near the river mouth and coastal seawater using a 59Fe radiotracer method. According to our results, the investigated river contributed “truly dissolved” Fe concentrations of about 3300 nmol L− 1 to the ocean which is nearly two orders of magnitude higher than the dissolved iron contribution of the “average world” river (∼ 40 nmol L− 1). Thus we conclude that peatland-draining rivers are important sources of dissolved iron to the ocean margins. We propose highly electrostatic and sterical stabilized iron-organic matter complexes in the size range of < 2 kDa to be responsible for iron transport across the estuarine mixing zone. 相似文献
58.
Débora Ravelli Carla Romero Matsuoka Regina Célia Della Modesta Thais Maria Ferreira de Souza Vieira Marisa Aparecida Bismara Regitano-d’Arce 《Journal of the American Oil Chemists' Society》2010,87(5):515-520
Measurements of degradation in frying oils are mainly based on physico-chemical properties. Total polar compounds (TPC) and
free fatty acids (FFA) content in frying oils are used as a guide for discarding used oils. The purpose of this study was
to evaluate the efficacy of a sensory method in detecting degradation in soybean oils used in potato chips deep frying. The
sensory evaluation of oil samples was determined by a trained panel; after rigorous selection and training steps. Free fatty
acid, TPC and Rancimat induction period (IP) were quantified in the same samples. The proposed sensory method was sensitive
to small differences in rancidity. The selected and trained sensory panel discarded oil samples with 0.175% FFA as oleic acid,
18.92% TPC, and 0.20 h IP. According to the results achieved in this research sensorial trained panel response is sensitive
and accurate in refusing deteriorated frying oils. Besides this, soybean oil can be used for deep frying procedures and safely
discarded according to the panel response, although presenting up to 7% linolenic acid. 相似文献
59.
Michal Nabrzyski Regina Gajewska 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1995,201(4):307-310
The levels of aluminium and fluoride have been determined in hospital daily diets including breakfast, dinner and supper, as well as in black teas and herbal teas purchased from the local market. In tea, aluminium was determined directly in a sample solution by atomic absorption spectroscopy using nitrous oxide and an acetylene flame. For analysis of the hospital diet, samples containing lower levels of aluminium were analysed using a spectrophotometric method which measured aluminium in the form of a 8-hydroxyquinoline complex. Decomposition of the samples was achieved using a mixture of concentrated acids [nitric (HNO3), perchloric (HClO4) and sulphuric (H2SO4)] in platinum dishes. Fluoride was assayed by spectrophotometry using a microdiffusion procedure with a mixture of concentrated HClO4 and silver sulphate, trace amounts of the released fluoride [as hydrogen fluoride (HF)] were trapped on the alkaline surface of a Petri dish and then determined in the form of an alizarin-fluoride complex. The mean level of aluminium found in hospital daily diets amounted to 21.3±12.3 mg and the mean level of fluoride was 1.38±1.12 mg per adult person. In the 16 samples of commercially available brands of black teas, the levels of aluminium and fluroide ranged from 445 to 1552 ppm (mean=897±264 ppm) and from 30 to 340 ppm (mean 141±85 ppm), respectively. In six herbal teas, the mean levels of aluminium and fluoride were lower, and amounted to 218.9±150.7 ppm and 6.0±6.9 ppm, respectively. This study has shown that concern about a high intake of aluminium and fluoride from these foods is unfounded. 相似文献
60.
Karina Cardoso Tramonte João Gustavo Provesi Iolanda Moreira Dutra Albuquerque E Silva Aureanna Nairne Negrão Murakami Marcelo Maraschin Renata Dias De Mello Castanho Amboni Edna Regina Amante 《International Journal of Food Science & Technology》2011,46(9):1871-1877
The heart of palm is a food extracted from several species of palm trees. Only 10–20% of the raw material is transformed into canned hearts of palm, therefore this agro‐industry generates a large quantity of solid residue. The aim of this work was to extract and characterise a juice produced from this solid residue. This extract is compared with the traditional fruit juices (orange and pineapple juices), obtaining higher contents of minerals, such as magnesium (22.80 mg/100 g) and potassium (276.90 mg/100 g), phenolic compounds (gallic, 3,4‐dihydroxybenzoic, chlorogenic, syringic and caffeic acids) and high free radical scavenging capacity (expressed as 2,2‐diphenyl‐1‐picrylhydrazyl), which suggest high antioxidant activity. Additionally, a new soft drink was formulated using this king palm juice as its main ingredient. The soft drink samples formulated with this juice had high sensory acceptability and high intention of consumption, which suggests an important and low‐cost application for this industrial residue. 相似文献