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71.
Parker Karen J.; Hoffman Christy L.; Hyde Shellie A.; Cummings Carl S.; Maestripieri Dario 《Canadian Metallurgical Quarterly》2010,124(3):428
There is growing interest in examining oxytocin and social functioning in human and non-human primates. Studies of human oxytocin biology are typically restricted to peripheral assessments because opportunities to collect cerebrospinal fluid (CSF) are rare. Several studies have examined CSF oxytocin levels in captive adult primates, but none to our knowledge have been conducted under free-ranging conditions and inclusive of infants. The main goal of this study was to establish feasibility of quantifying CSF oxytocin levels in free-ranging adult female and infant rhesus monkeys living on Cayo Santiago, PR. CSF oxytocin levels were examined in relation to individuals' demographic and reproductive characteristics as well as plasma cortisol levels. CSF oxytocin concentrations ranged from 36.02 to 134.41 pg/ml in adult females (ages 7–26 years; N = 31) and 35.94 to 77.3 pg/ml in infants (ages 38–134 days; N = 17). CSF oxytocin levels were positively correlated with adult female age and negatively correlated with infant age. The former correlation was driven by reproductive status. CSF oxytocin levels were unrelated to dominance rank or plasma cortisol levels. In contrast to a previous study of plasma oxytocin concentrations in this population, CSF oxytocin levels did not differ significantly between lactating and non-lactating females. These findings: 1) provide feasibility data for examining CSF oxytocin levels in free-ranging non-human primates and 2) indicate that CSF oxytocin levels may be a biomarker of age-related central nervous system changes across lifespan development. Research is now required to examine CSF oxytocin levels in the context of social functioning in free-ranging rhesus monkeys. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
Siedlecki Karen L.; Manly Jennifer J.; Brickman Adam M.; Schupf Nicole; Tang Ming-Xin; Stern Yaakov 《Canadian Metallurgical Quarterly》2010,24(3):402
Objective: The purpose of this study was to examine whether neuropsychological tests translated into Spanish measure the same cognitive constructs as the original English versions. Method: Older adult participants (N = 2,664), who did not exhibit dementia from the Washington Heights Inwood Columbia Aging Project (WHICAP), a community-based cohort from northern Manhattan, were evaluated with a comprehensive neuropsychological battery. The study cohort includes both English (n = 1,800) and Spanish speakers (n = 864) evaluated in their language of preference. Invariance analyses were conducted across language groups on a structural equation model comprising four neuropsychological factors (memory, language, visual-spatial ability, and processing speed). Results: The results of the analyses indicated that the four-factor model exhibited partial measurement invariance, demonstrated by invariant factor structure and factor loadings but nonequivalent observed score intercepts. Conclusion: The finding of invariant factor structure and factor loadings provides empirical evidence to support the implicit assumption that scores on neuropsychological tests are measuring equivalent psychological traits across these two language groups. At the structural level, the model exhibited invariant factor variances and covariances. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
This study evaluated the antimicrobial potential of various naturally occurring substances, for use as active agents in cheese packaging. Sorbic acid and benzoic acid were examined as standard‐sized and nanoparticled solutions. Rosemary, curcumin and ascorbic acid were employed as nanoparticled solutions only, while non‐nanoparticled chitosan, of two molecular weights, were also selected for evaluation. All agents were assessed against micro‐organisms derived from cheese. Chitosan proved to be the most effective, with low molecular weight chitosan performing best. The most antimicrobial nanoparticle was found to be rosemary. Comparison of normal‐ and nanoparticle‐sized organic acid solutions showed little difference in terms of antimicrobial properties. 相似文献
74.
Paul Geoerg Florian Berchtold Steven Gwynne Karen Boyce Stefan Holl Anja Hofmann 《火与材料》2019,43(7):759-781
To quantify the evacuation process, evacuation practitioners use engineering egress data describing the occupant movement characteristics. These data are typically based to young and fit populations. However, the movement abilities of occupants who might be involved in evacuations are becoming more variable—with the building populations of today typically including increasing numbers of individuals: with impairments or who are otherwise elderly or generally less mobile. Thus, there will be an increasing proportion of building occupants with reduced ability to egress. For safe evacuation, there is therefore a need to provide valid engineering egress data considering pedestrians with disabilities. Gwynne and Boyce recently compiled a series of data sets related to the evacuation process to support practitioner activities in the chapter Engineering Data in the SFPE Handbook of Fire Protection Engineering. This paper supplements these data sets by providing information on and presenting data obtained from additional research related to the premovement and horizontal movement of participants with physical‐, cognitive‐, or age‐related disabilities. The aim is to provide an overview of currently available data sets related to, and key factors affecting the egress performance of, mixed ability populations which could be used to guide fire safety engineering decisions in the context of building design. 相似文献
75.
Raja Razuan Qun Chen Karen N. Finney Nigel V. Russell Vida N. Sharifi Jim Swithenbank 《Fuel Processing Technology》2011,92(12):2219-2225
Biomass is being generated in vast amounts from oil palm plantations particularly in developing countries such as Malaysia, Thailand and Indonesia. Oil palm stone (OPS) is currently considered a waste material and has not previously been considered for energy purposes. The main objective of this study was to investigate the thermochemical conversion of OPS in a pilot-scale fluidised bed combustor. The net heating value of OPS was 24.93 MJ/kg. The effect of primary air flowrate and initial bed temperature were the main parameters investigated. The bed and bed's surface temperature were found to decrease as the primary air flowrate increased. In all tests CO emissions were less than 0.2%. The emissions of SO2 and HCl ranged from 0.02 ppm to 0.05 ppm, significantly below the permitted levels set by legislation. Stable combustion was observed at a bed temperature of 950 °C. The most abundant elements found in the ash were Al, Ca, Fe, K, Mg, Mn, P, S and Si. However, due to the temperature regime used in the study fouling would not be an issue. 相似文献
76.
Mechanisms of cement hydration 总被引:3,自引:0,他引:3
Jeffrey W. Bullard Hamlin M. Jennings Richard A. Livingston Andre Nonat George W. Scherer Jeffrey S. Schweitzer Karen L. Scrivener Jeffrey J. Thomas 《Cement and Concrete Research》2011,41(12):1208-1223
The current state of knowledge of cement hydration mechanisms is reviewed, including the origin of the period of slow reaction in alite and cement, the nature of the acceleration period, the role of calcium sulfate in modifying the reaction rate of tricalcium aluminate, the interactions of silicates and aluminates, and the kinetics of the deceleration period. In addition, several remaining controversies or gaps in understanding are identified, such as the nature and influence on kinetics of an early surface hydrate, the mechanistic origin of the beginning of the acceleration period, the manner in which microscopic growth processes lead to the characteristic morphologies of hydration products at larger length scales, and the role played by diffusion in the deceleration period. The review concludes with some perspectives on research needs for the future. 相似文献
77.
Metallic nanoparticles functionalized with oligonucleotides are used for a number of nucleic acid detection strategies. However, oligonucleotide-nanoparticle conjugates suffer from a lack of stability when exposed to certain conditions associated with DNA detection assays. In this study, we report the synthesis of thiol and thioctic acid-modified oligonucleotide gold nanoparticle (OGNs) conjugates functionalized with a dye label and varying spacer groups. The thioctic acid-modified conjugates exhibit increased stability when treated with dithiothreitol (DTT) compared to the more commonly used thiol modification. When the dye labelled oligonucleotide nanoparticle conjugates are exposed to the same conditions there is a pronounced increase in the stability for both thioctic acid and thiol modified sequences. These results open up the possibility of simply using a dye label to enhance the stability of oligonucleotide-nanoparticle conjugates in DNA detection assays where the enhanced stability of the conjugate system can be advantageous in more complex biological environments. 相似文献
78.
Maki EC Rodstein J Millar JG Barbour KS Hanks LM Barbour JD 《Journal of chemical ecology》2011,37(7):714-716
Earlier work has shown that adult male Prionus californicus Motschulsky (Coleoptera: Cerambycidae) are attracted to the female-produced compound (3R,5S)-3,5-dimethyldodecanoic acid, and to a synthetic mixture of the four stereoisomers of 3,5-dimethyldodecanoic acid. Here, we report the results of field trials that tested whether or not three structurally related compounds (methyl 3,5-dimethyldodecanoate, 3,5-dimethyltridecanoic acid, and 3,5-dimethylpentadecanoic acid), present in extracts of virgin females, are attractive, and whether or not they influence attraction to 3,5-dimethyldodecanoic acid. In a trial with single components, only traps baited with the acid or its methyl ester captured more beetles than did control traps; catches to the acid were five times higher than to the methyl ester. Another trial, excluding 3,5-dimethyldodecanoic acid, confirmed the activity of the methyl ester. Finally, addition of the three compounds to 3,5-dimethyldodecanoic acid, in the ratio found in extracts from female beetles, gave a catch similar to that of traps baited with 3,5-dimethyldodecanoic acid alone. Consequently, the function of these minor compounds remains undetermined. 相似文献
79.
The incidence and mortality of pancreas cancer converge. There has been little advancement in the treatment of pancreas cancer since the acceptance of gemcitabine as the standard therapy. Unfortunately, the efficacy of gemcitabine is dismal. While there is much discussion for the development of biomarkers to help direct therapy in this area, there is little action to move them into clinical practice. Herein, we review potential pancreatic cancer biomarkers and discuss the limitations in their implementation. 相似文献
80.
De Vico L Iversen L Sørensen MH Brandbyge M Nygård J Martinez KL Jensen JH 《Nanoscale》2011,3(9):3635-3640
A single charge screening model of surface charge sensors in liquids (De Vico et al., Nanoscale, 2011, 3, 706-717) is extended to multiple charges to model the effect of the charge distributions of analyte proteins on FET sensor response. With this model we show that counter-intuitive signal changes (e.g. a positive signal change due to a net positive protein binding to a p-type conductor) can occur for certain combinations of charge distributions and Debye lengths. The new method is applied to interpret published experimental data on Streptavidin (Ishikawa et al., ACS Nano, 2009, 3, 3969-3976) and Nucleocapsid protein (Ishikawa et al., ACS Nano, 2009, 3, 1219-1224). 相似文献