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41.
Sunil Pandey Ritu Shah Ashmi Mewada Mukeshchand Thakur Goldie Oza Madhuri Sharon 《Journal of materials science. Materials in medicine》2013,24(7):1671-1681
Use of cysteamine hydrochloride (Cys-HCl) protected gold nanorods (GNRs) as efficient carrier of widely used anti-cancer drug doxorubicin using folic acid as navigational molecule is presented in this work. GNRs were found to have excellent drug loading capacity of >97 %. A detailed comprehension of in vitro drug release profile under ideal physiological condition was found to obey 1st order kinetics at pH 6.8, 5.3 and 7.2, an ideal milieu for drug delivery to solid tumours. 相似文献
42.
Mealtime Behaviors and Food Consumption of Perceived Picky and Nonpicky Eaters through Home Use Test
Mandy Boquin Sarah Smith‐Simpson Sharon M. Donovan Soo‐Yeun Lee 《Journal of food science》2014,79(12):S2523-S2532
Picky eating has been investigated through numerous surveys and food recalls, but few studies have applied in‐home meal evaluations as a method to investigate behaviors and food preferences of children perceived by their parent to be a picky eater (PE) or nonpicky eater (NPE). A 2‐wk in‐home meal study was completed to investigate differences in PE and NPE mealtime behaviors and food selections using real‐time parental observations. Parents (n = 170) and their 2‐ to 4‐y‐old children (83 PE and 87 NPE) evaluated 5 standardized meals in‐home. Parents recorded their child's and their own hedonic liking of the products and completed an assessment of their child's behavior and consumption at each meal. Significant differences were found between perceived PE and NPE children for all 16 behaviors assessed. On average, perceived NPE were assessed to consume a higher percentage of the meal served and to have higher acceptance scores for most of the foods evaluated. Some foods, though, like breaded chicken and plain pasta, were liked equally by PE and NPE. Several significant differences in hedonic liking were revealed when PE children were compared to their parents. Yet, few differences in liking occurred between NPE children and their parents or between the 2 parental groups. Because study participants evaluated meals real‐time rather than memory recall, the differences and similarities found between perceived PE and NPE may be considered direct experiential evidence with reduced subjective bias as created when subjects recall past experiences. Thus, findings from this study can provide the foundation to establish an objective definition and classification of PE and NPE. 相似文献
43.
Information extraction (IE) is an important and growing field, in part because of the development of ubiquitous social media networking millions of people and producing huge collections of textual information. Mined information is being used in a wide array of application areas from targeted marketing of products to intelligence gathering for military and security needs. IE has its roots in artificial intelligence fields including machine learning, logic and search algorithms, computational linguistics, and pattern recognition. This review summarizes the history of IE, surveys the various uses of IE, identifies current technological accomplishments and challenges, and explores the role that neural and adaptive computing might play in future research. A goal for this review is also to encourage practitioners of neural and adaptive computing to look for interesting applications in the important emerging area of IE. 相似文献
44.
The instructions used in think-aloud studies can range from a simple request to think-aloud, to an explicit instruction to include certain types of content. The present study compared two think-aloud instructions: the classic neutral think-aloud instruction and an explicit instruction requesting explanations and content that is relevant to the user experience. Data from task performance, mental workload, think-aloud protocols and usability problems were collected from 16 participants, equally distributed between the two think-aloud instruction conditions. No differences were found in task performance, however, participants in the explicit instruction condition reported higher mental workload and a focus on finding interface problems. The explicit instruction condition also yielded more utterances about the user experience, expectations and explanations of behaviour than the neutral condition. An analysis of the resultant usability problems revealed that the explicit instruction led to a larger number of dialogue, navigation, layout and functionality problems, but that the problems which were unique to this condition were, in the main, at a low level of severity. 相似文献
45.
Biemer Paul P.; Christ Sharon L.; Wiesen Christopher A. 《Canadian Metallurgical Quarterly》2009,14(4):400
Scale score measures are ubiquitous in the psychological literature and can be used as both dependent and independent variables in data analysis. Poor reliability of scale score measures leads to inflated standard errors and/or biased estimates, particularly in multivariate analysis. Reliability estimation is usually an integral step to assess data quality in the analysis of scale score data. Cronbach’s α is a widely used indicator of reliability but, due to its rather strong assumptions, can be a poor estimator (L. J. Cronbach, 1951). For longitudinal data, an alternative approach is the simplex method; however, it too requires assumptions that may not hold in practice. One effective approach is an alternative estimator of reliability that relaxes the assumptions of both Cronbach’s α and the simplex estimator and thus generalizes both estimators. Using data from a large-scale panel survey, the benefits of the statistical properties of this estimator are investigated, and its use is illustrated and compared with the more traditional estimators of reliability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
Influence of 1,2‐polybutadiene on properties of dicumyl peroxide cured brominated butyl rubber
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Peroxide curing of brominated butyl rubber (BIIR) is an attractive topic, but the degradation of BIIR during the curing is a drawback needed to be overcome. Coagent assisted peroxide curing system is an attractive and effective choice in order to increase the crosslink density of rubbers. 1,2‐polybutadiene (1,2‐PB) is used as a crosslinking coagent for the curing of BIIR by dicumyl peroxide (DCP), and the effect of 1,2‐PB on the curing characteristics, crosslink density, and mechanical properties is investigated. The addition of 1,2‐PB affects the curing characteristics of BIIR compound and significantly increases the crosslink density of BIIR vulcanizates. With increasing 1,2‐PB content, the tensile strength and stresses at a given extension of BIIR vulcanizates increase, but the elongation at break decreases. A stress‐softening effect of the carbon black filled BIIR vulcanizates is observed and becomes more pronounced with increasing 1,2‐PB content. The addition of 1,2‐PB increases the stress relaxation index of BIIR. GPC and 13C‐NMR results indicate 1,2‐PB participates in the crosslinking reaction, and the existence of 1,2‐PB component in the insoluble fraction of BIIR/1,2‐PB vulcanizates is confirmed by solid‐state 13C‐NMR. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43280. 相似文献
47.
Perrone Sharon Grossman Julie Liebman Alex Sooksa-nguan Thanwalee Gutknecht Jessica 《Nutrient Cycling in Agroecosystems》2020,117(1):61-76
Nutrient Cycling in Agroecosystems - Legume cover crops can play a valuable role in maintaining and increasing soil quality and nitrogen availability, but are infrequently grown in the Upper... 相似文献
48.
Methyl iodide (MeI) is considered a very promising fumigant alternative to methyl bromide (MeBr) for controlling soil-borne pests. Because atmospheric emission of highly volatile fumigants contributes to air pollution, feasible strategies to reduce emissions are urgently needed. In this study, thiourea (a nitrification inhibitor) was shown to accelerate the degradation of MeI in soil and water. In aqueous solution, the reaction between MeI and thiourea was independent of pH, although the rate of MeI hydrolysis increased in alkaline solution. Substantial increases in the rate of MeI dissipation were observed in thiourea-amended soils. Transformation of MeI by thiourea in aqueous solution was by a single chemical reaction process, while MeI degradation in thiourea-amended soil apparently involved a catalytic mechanism. The electron delocalization between the thiourea molecule and the surfaces of soil particles is energetically favorable and would increase the nucleophilic reactivity of the thiono group toward MeI, resulting in an enhancement of the dissipation rate. The soil half-life for MeI was reduced from >300 h for unamended soils to only a few hours in soil or sand amended with thiourea at a 2:1 molar ratio (thiourea:MeI). The MeI transformation rate in thiourea-amended soil increased with increasing soil temperature and decreasing soil moisture. Therefore, spraying thiourea on the soil surface to form a "reactive surface barrier" may be an effective and innovative strategy for controlling fumigant emissions to the atmosphere and for improving environmental protection. 相似文献
49.
Catechol oxidase from apple chloroplasts and browning of apple slices are strongly inhibited by the chloride anion. The inhibition is non-competitive and reversible. Inhibition is pH-dependent. being observed at pH 5.1 but not at pH 7.3. Activity could be extracted from the particles using CTAB. The extract's activity at the two pH could not be resolved into distinct fractions. The pH-dependence of inhibition is ascribed to a change in the tertiary structure of the enzyme. 相似文献
50.
Robert A. Gibson Mark A. Neumann Sharon L. Burnard Josephine A. Rinaldi Glen S. Patten Edward J. McMurchie 《Lipids》1992,27(3):169-176
Adult male marmoset monkeys were fed eicosapentaenoic acid (20∶5n−3) as the ethyl ester in diets containing either 32% (reference
diet, no added cholesterol) or 7% (atherogenic diet with 0.2% added cholesterol) linoleic acid (18∶2n−6) for 30 wk. No changes
were seen in the level of phosphatidylcholine (PC) or phosphatidylethanolamine (PE) but minor changes were observed in both
the sphingomyelin (SPM) and phosphatidylinositol plus phosphatidylserine (PI+PS) fractions of erythrocyte lipids. The extent
of total n−3 fatty acid incorporation into membrane lipids was higher in atherogenic diets (polyunsaturated/monounsaturated/saturated
(P/M/S) ratio 0.2∶0.6∶1.0) than reference diets (P/M/S ratio 1∶1∶1) and this was true for both PE (33.4±1.0%vs 24.3±1.1%) and PC (9.3±0.5%vs 4.9±0.3%). Although suitable controls for cholesterol effects were not included in the study, earlier results obtained with
marmosets lead us to believe such effects were probably small. Regardless of basic diet (atherogenic, reference), 20∶5n−3
was preferentially incorporated into PE (10.8±0.2%, 6.0±0.02%) while smaller amounts were incorporated into PC (6.9±0.4%,
3.2±0.2%). The major n−3 polyunsaturated fatty acid found in PE in response to dietary 20∶5n−3 was the elongation metabolite
22∶5n−3 in both the atherogenic (17.7±0.7%) and reference (14.3±1.0%) dietary groups; 22∶6n−3 levels were less affected by
diet (4.7±0.3% and 3.9±0.2%, respectively). The results can be interpreted to indicate an inverse relationship between the
amount of dietary 18∶2n−6 and incorporation of 20∶5n−3 into erythrocyte membrane phospholipids regardless of whether the major
dietary n−3 fatty acid was α-linolenate (18∶3n−3) or 20∶5n−3. This interpretation is supported by theoretical calculations. 相似文献