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151.
152.
Lorch Elizabeth Pugzles; Diener Mary Beth; Sanchez Rebecca Polley; Milich Richard; Welsh Richard; van den Broek Paul 《Canadian Metallurgical Quarterly》1999,91(2):273
This study explored influences of story structure properties on recall of story events by children with and without attention deficit hyperactivity disorder (ADHD). Participants listened to and retold 2 stories. Two properties of the stories' causal structure were derived: the number of causal connections an event has to other events and whether an event is on the causal chain linking events from beginning to end. The extent to which causal properties and the more subjective property of perceived importance predicted recall in the 2 groups of children was examined. Each property predicted recall, but there were group differences in sensitivity to causal structure that were moderated by intelligence level and gender. Variations in amount and allocation of cognitive resources applied to comprehension contributed to performance of children with ADHD. There are implications for understanding academic and social difficulties common in children with ADHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
153.
Workflow Systems: Occasions for Success and Failure 总被引:3,自引:0,他引:3
Rebecca E. Grinter 《Computer Supported Cooperative Work (CSCW)》2000,9(2):189-214
Workflow technologies have created considerable discussion within the computer supported cooperative work community. Although a number of theoretical and empirical warnings about the difficulties of workflow systems have appeared, the technologies continue to be built and sold. This paper examines the use of one workflow-like system and outlines three cases when the technology supported the work of its users. Comparing these successful occasions with some reports of difficulties, this paper draws conclusions about the circumstances that led to tool usage. 相似文献
154.
155.
Using the statistically optimised method, submicron magnetic polyglutaraldehyde nanoparticles (Fe-PGNP) with free surface carboxylic groups have been synthesized. A model anticancer agent methotrexate (MTX) has been chemically bonded onto the surface of these particles using poly-l-Lysine (PL) as a spacer. The drug release characteristics of the final delivery device, i.e. [Fe-PGNP]-PL-MTX, has been elucidated at 37˚C in a medium containing a proteolytic enzyme. Results demonstrate that using particles containing about 8% w/w of Fe3O4, and PL-MTX conjugate constituting 256 μg MTX per mg of PL, almost 50% of the conjugate can be covalently linked onto the carrier surface. Release studies failed to demonstrate the presence of free drug. However it appears that MTX-oligopeptides are released from the carrier as a result of the enzymatic hydrolysis of biodegradable bonds. It is suggested that [Fe-PGNP]-PL-MTX may be useful in the intracellular active targeting of bonded drug(s). 相似文献
156.
McKay James R.; Pettinati Helen M.; Morrison Rebecca; Feeley Michael; Mulvaney Francis D.; Gallop Robert 《Canadian Metallurgical Quarterly》2002,16(3):225
This study examined the relation between depression diagnoses and outcomes in 132 cocaine-dependent patients who were randomized to relapse prevention (RP) or standard 12-step focused group continuing rare and followed for 2 years. Depressed patients attended more treatment sessions and had more cocaine-free urines during treatment than participants without depression, but they drank alcohol more frequently before treatment and during the 18-month posttreatment follow-up. Cocaine outcomes in depressed patients deteriorated to a greater degree after treatment than did cocaine outcomes in patients without depression, particularly in patients in RP who had a current depressive disorder at baseline. The best alcohol outcomes were obtained in nondepressed patients who received RIP. The results suggest that extended continuing care treatment may be warranted for cocaine-dependent patients with co-occurring depressive disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
157.
A hyperelastic–viscoplastic constitutive model for amorphous polymers was used in finite element simulations of micro‐hot embossing across the glass transition. The model was selected for its ability to capture finite strain temperature and rate dependence over a wide range of temperatures, including across the glass transition. The simulations focused on the glass transition temperature regime, and particularly probed the effects of time and temperature during cooling and mold release. The results show that strong temperature sensitivity of the material across the glass transition leads to a wide range of required embossing force and springback. The interplay between changes in material properties upon cooling and stress relaxation can lead to significant increases in embossing force during the cooling stage, especially when high cooling rates are employed. The effects of thermal expansion also complicate the problem during rapid cooling. Nonlinear material behavior is shown to affect results in parametric hot embossing studies. Careful tailoring of embossing temperature, cooling rate, and demolding temperature is critical in acceptable feature replication. The best results are found for moderate cooling rates, which allow adequate time for stress relaxation in the material prior to mold release. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers 相似文献
158.
This paper considers aspects of environmental social science research in the UK and explores an obvious bias towards the development of instruments to manage demand as an adaptation to climate change, and consequently the predominance of interest in the customer from a demand-side perspective. In the case of water, this has resulted in an inappropriate mixing of individualist research methods designed to measure public perceptions of risk and water-based practices, with mass consumption data that cannot be specifically linked to the individual. This mixing has a tendency to reinforce a long-standing blame culture that drives interest in the development of behaviour change initiatives while the relatively unchallenged hydraulic mission to provide safe drinking water and sanitation progresses. With this in mind this paper reviews examples of water use research from California, Australia, and the UK and highlights the more effective routes to understanding water customers and developing behaviour change initiatives that utilise stages of change models and grounded techniques incorporating qualitative and quantitative data from individual sources. A secondary aim is to argue for re-framing the relations between various actors in a changing climate to allow the development of new policy approaches, learning, and openness, from industry, regulators, and customers, based on new theories from the field. 相似文献
159.
Compas Bruce E.; Howell David C.; Phares Vicky; Williams Rebecca A.; Ledoux Normand 《Canadian Metallurgical Quarterly》1989,25(4):550
This study assessed major and daily stressful life events and psychological symptoms in a sample of young adolescents and their parents. The relation between major life events and symptoms was mediated by daily stressors for parents and their young adolescent children. Children's emotional and behavioral problems were associated with fathers' psychological symptoms but not with mothers' symptoms. Both mothers' and fathers' symptoms were associated with their sons' daily stressors, but girls' daily stressors were related only to their mothers' symptoms. Mothers' symptoms were associated with their husbands' daily hassles in families of young adolescent boys, and both parents' symptoms were associated with their spouses' hassles in families of adolescent girls. Highlights the importance of studying stress processes between individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
160.
A potential methodology is presented for the systematic prediction of EELS edges using DFT, suitable for codes that calculate ELNES for a specific atom in a unit cell. The method begins with the selection of a unit cell, chosen as the smallest cell that still provides a physically valid representation of the bulk material. Within this small cell, a single electron core–hole is included in the atom for which the EELS ionisation edge is to be calculated. The basis-set size and k-point mesh of the DFT calculation are converged specifically against the predicted EELS result. Subsequently, the cell size is increased until the theoretical core–holes no longer interfere. At this point one can then modify the exact core–hole approximation. This methodology was applied to the new EELS module of the CASTEP pseudopotential DFT code, as well as the all-electron code Wien2k. Aluminium K edges were investigated for various aluminium metal systems. It was observed that as the cell size was increased the predicted EELS result became less sensitive to the exact core–hole approximation used. It was noted however that due to high screening in metals a ground state single cell calculation is often acceptable. The semiconductor aluminium nitride (wurtzite form) was also investigated. It was observed that for both Wien2k and CASTEP, with careful convergence of the key DFT code parameters, single cell ground state calculations gave a reasonable agreement with experiment, contrary to what might be expected for a semiconductor with a large band gap. This was particularly true of the Wien2k result. Given the greater computational effort required for supercell calculations, these results are likely to form the beginnings of a detailed investigation into accepted methods of ELNES predictions. 相似文献