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71.
In 2002, the authors established a baseline for Internet users' online privacy values, finding information transfer, notice/awareness, and information storage were the top online privacy concerns. Since this survey, many privacy-related events have occurred, including changes in online trends and the creation of laws, prompting the authors to rerun the survey in 2008 to examine how these events might have affected users' online privacy concerns. In this article, they discuss the 2008 survey, which revealed that US Internet users' top three privacy concerns didn't change over the course of six years, although their level of concern did. The authors also examine differences in privacy concerns between US and international respondents. The Web extra groups the survey statements according to six dimensions of privacy concerns based on the following classifications—personalization, notice/awareness, information transfer, information collection, information storage, and access/participation. 相似文献
72.
Simon Jessica R.; Howard James H. Jr.; Howard Darlene V. 《Canadian Metallurgical Quarterly》2010,24(4):534
Objective: Past research has investigated age differences in frontal-based decision making, but few studies have focused on the behavioral effects of striatal-based changes in healthy aging. Feedback learning has been found to vary with dopamine levels; increases in dopamine facilitate learning from positive feedback, whereas decreases facilitate learning from negative feedback. Given previous evidence of striatal dopamine depletion in healthy aging, we investigated behavioral differences between college-aged and healthy older adults using a feedback learning task that is sensitive to both frontal and striatal processes. Method: Seventeen college-aged (M = 18.9 years) and 24 healthy, older adults (M = 70.3 years) completed the Probabilistic Selection task, in which participants are trained on probabilistic stimulus-outcome information and then tested to determine whether they learned more from positive or negative feedback. Results: As a group, the older adults learned equally well from positive and negative feedback, whereas the college-aged group learned more from positive than negative feedback, F(1, 39) = 4.10, p effect = .3. However, these group differences were not due to older individuals being more balanced learners. Most individuals of both ages were balanced learners, but while all of the remaining young learners had a positive bias, the remaining older learners were split between those with positive and negative learning biases (χ2(2) = 6.12, p 相似文献
73.
Brian T. Story Michael A. Urynowicz Drew W. Johnson Jessica A. Morris 《Canadian Metallurgical Quarterly》2009,135(1):87-95
Researchers used column and flume experiments with uniform silica sand with and without suspended solids to examine the extent and longevity of hydraulic conductivity reduction (HCR) resulting from three anionic polyacrylamide (PAM) application methods, liquid injection, slurry surface, and granular surface application. Low turbidity (0.4 NTU) liquid injection column tests showed 20–65% HCR, likely caused by an extensional viscosity mechanism. HCR increased as turbidity increased, especially at low PAM concentrations. High turbidity (100 NTU) liquid injection column tests showed 66–77% HCR, likely through surficial PAM–clay aggregate filtration. Column and adsorption tests strongly suggest PAM–sand adsorption does not cause substantial HCR. In low turbidity flume tests, PAM slurry application to the sand surface produced up to 100% HCR, likely through a viscosity mechanism, and granular application to the media surface produced up to 100% HCR, likely through fixed surficial polymer gel formation. Hydraulic conductivity returned to control-adjusted pretreatment levels following PAM application in all tests except granular surface application at high mass loads or with high turbidity. 相似文献
74.
Jun Wang Cheuk Tang Mario G. Ferruzzi Bing Gong Brian J. Song Elsa M. Janle Tzu‐Ying Chen Bruce Cooper Merina Varghese Alice Cheng Daniel Freire Amanda Bilski Jessica Roman Tuyen Nguyen Lap Ho Stephen T. Talcott James E. Simon Qingli Wu Giulio M. Pasinetti 《Molecular nutrition & food research》2013,57(12):2091-2102
75.
Jessica R. Chocha Pooja A. Chhelavda J. A. Bhalodia 《Transactions of the Indian Institute of Metals》2011,64(1-2):159-163
A new simple route was used to synthesize nanosized crystalline La0.67Ca0.33MnO3 perovskite type complex oxide by simple citrate pyrolysis process using a metal salts, La, Ca, Mn as starting materials. To obtain the LCMO nanoparticles the precursor was carried out at various calcination temperatures viz. 500° C, 600° C, 700° C, 800° C for very short time only ~ 60 minutes. The synthesized LCMO nanoparticles were characterized by powder XRD, FTIR, TGA/DTA, SEM. The precursor could be completely decomposed into complex oxide at temperature below 500° C according to the TGA/DTA results. XRD demonstrates that the decomposed species is composed of perovskite-type structure at calcination temperature of 600° C for 60 minutes. The crystalline size that depends on the calcination temperature of the precursor is in the range of 11–22 nm as determined by Scherrer Formula. All the prepared samples have high purity perovskite structure which is orthorhombic. The chemical bonds were identified by the measurements of Infrared IR transmission spectra carried out with powder samples in which KBr was used as a carrier. The IR spectra revealed that stretching and bending modes influenced by calcination temperature. Morphology and grain size were studied through scanning electron microscopy. 相似文献
76.
Wagenmakers, Wetzels, Borsboom, and van der Maas (2011) argued that psychologists should replace the familiar “frequentist” statistical analyses of their data with Bayesian analyses. To illustrate their argument, they reanalyzed a set of psi experiments published recently in this journal by Bem (2011), maintaining that, contrary to his conclusion, his data do not yield evidence in favor of the psi hypothesis. We argue that they have incorrectly selected an unrealistic prior distribution for their analysis and that a Bayesian analysis using a more reasonable distribution yields strong evidence in favor of the psi hypothesis. More generally, we argue that there are advantages to Bayesian analyses that merit their increased use in the future. However, as Wagenmakers et al.'s analysis inadvertently revealed, they contain hidden traps that must be better understood before being more widely substituted for the familiar frequentist analyses currently employed by most research psychologists. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
77.
Perturbed quantization steganography 总被引:3,自引:0,他引:3
In this paper, we use the recently proposed wet paper codes and introduce a new approach to passive-warden steganography called
perturbed quantization. In perturbed quantization, the sender hides data while processing the cover object with an information-reducing
operation that involves quantization, such as lossy compression, downsampling, or A/D conversion. The unquantized values of
the processed cover object are considered as side information to confine the embedding changes to those unquantized elements
whose values are close to the middle of quantization intervals. This choice of the selection channel calls for wet paper codes
as they enable communication with non-shared selection channel. Heuristic is presented that indicates that the proposed method
provides better steganographic security than current JPEG steganographic methods. This claim is further supported by blind
steganalysis of a specific case of perturbed quantization for recompressed JPEG images. 相似文献
78.
Security in the wild: user strategies for managing security as an everyday,practical problem 总被引:1,自引:0,他引:1
Paul?DourishEmail author Rebecca?E.?Grinter Jessica?Delgado de la Flor Melissa?Joseph 《Personal and Ubiquitous Computing》2004,8(6):391-401
Ubiquitous and mobile technologies create new challenges for system security. Effective security solutions depend not only on the mathematical and technical properties of those solutions, but also on people’s ability to understand them and use them as part of their work. As a step towards solving this problem, we have been examining how people experience security as a facet of their daily life, and how they routinely answer the question, “is this system secure enough for what I want to do?” We present a number of findings concerning the scope of security, attitudes towards security, and the social and organizational contexts within which security concerns arise, and point towards emerging technical solutions. 相似文献
79.
The measurement of minute samples is desirable in many areas of research and analysis, including biological, environmental, and forensic sciences. The use of manual solution direct deposition, combined with surface evaporation, is a very useful and convenient method for the transfer of many analytes to a spectroscopic sampling window. For Fourier transform infrared (FT-IR) spectrometric analysis, high quality attenuated total reflection (ATR) and transmission analyses are possible with suitable solution deposits. If the sample area is very small, placement of the analyte deposit on the active area of the sampling accessory must be done carefully. To achieve this, a novel direct deposition system has been developed. This system, a series of valves attached to a glass nebulizer, generates deposits that are reproducible, and placement of the deposits is precise. The valves allow the sample to be loaded, helium airflow to expel the sample, and the nebulizer to be cleaned after deposition. To help contain the sample to a small area once deposition has taken place, a vacuum line is attached to the nebulizer. This simple semiautomated deposition system allows for higher sensitivity and run-to-run reproducibility for minute sample analysis. 相似文献
80.
Young Erin E.; Baumbauer Kyle M.; Hillyer Jessica; Joynes Robin L. 《Canadian Metallurgical Quarterly》2007,121(5):1073
Recent findings indicate that neonatal injury results in decreased spinal plasticity in adult subjects (E. E. Young, K. M. Baumbauer, A. E. Elliot, & R. L. Joynes, 2007). Previous research has shown that acute manipulations of pain processing (i.e., administration of formalin, carrageenan, capsaicin) result in a loss of spinal behavioral plasticity (A. R. Ferguson, E. D. Crown, & J. W. Grau, 2006). Moreover, neonatal injury results in a lasting reduction in adult spinally mediated plasticity resembling the deficit seen following acute manipulations in adults (E. E. Young et al., 2007). The present study was designed to determine whether the effects of neonatal injury could be prevented by lidocaine administration during the initial healing period. Subjects (injured or uninjured) received lidocaine or saline on 1 of 4 administration schedules (preinjury only, postinjury only, for 24 hr postsurgery, or for 72 hr postsurgery). Results demonstrated that lidocaine administration did not prevent the hypersensitivity and reduced spinal plasticity associated with neonatal injury. This suggests that (a) the mechanisms underlying neonatal injury are independent of peripheral input in the initial healing period and (b) lidocaine is ineffective at preventing long-term spinal plasticity changes following neonatal injury. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献