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121.
To examine whether young, middle-aged, and older adults view the concept of intelligent person as similar or different during adulthood, 140 adults of various ages rated how likely it would be for individuals of average and exceptional intelligence at 30, 50, and 70 yrs of age to be engaged in behaviors previously identified by adults as characterizing adult intelligence. Adults perceived more similarity between exceptionally intelligent prototypes of closer ages (i.e., 30 and 50 yrs; 50 and 70 yrs). Intelligence was perceived to consist of interest and ability to deal with novelty, everyday competence, and verbal competence (dimensions that were perceived to be differentially important for different-aged prototypes and by individuals of different ages). Participants' conceptions also included the idea that intelligence is malleable and that abilities differentially increase or decrease across the life span. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
122.
Play therapists are an extremely diverse lot. We come most often from the disciplines of psychology, psychiatry, social work, and education and adhere to theoretical points of view ranging from Jungian to ecosystemic to behavioral. When the creation of The International Journal of Play Therapy and a call for papers was announced in three different professional newsletters, authors from all of the above mentioned fields responded. Choosing which articles to include in this, the premiere issue, was difficult. The final selection is as representative of the entire spectrum of thought and practice current in our community as could be. We wish to offer this work as a new source of useful information and ideas about the broad field of play therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
123.
Investigated the control judgments of Type A (coronary-prone) and Type B (noncoronary-prone) actors and observers after 5 tasks in which actual response–outcome contingency and success were varied systematically. 40 male and 40 female undergraduates, classified as Type A or B on the Jenkins Activity Survey, performed the control task or served as observers in same-sex pairs. Overall, actors provided higher control judgments than did observers, and both actual contingency and success influenced judged control. Type A and B actors did not differ in their self-perceptions of control, but observers judged the Type A actors to have exerted more control than the Type B actors, primarily on positive contingency tasks. Findings suggest that Type A's, because of their more dynamic style, may be credited by observers with more control or competence than is warranted. By contrast, the more relaxed style of the Type B may lead to lower than warranted evaluations of control or competence. Type A's were found to learn the contingencies better than Type B's, which has important implications for the actual exercise of control. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
124.
The formation of colloidal unimolecular polymer (CUP) particles from single polymer strands was investigated as a function of molecular weight. The CUP particle size was correlated with the absolute molecular weight and its distribution. The characteristics of the particles were evaluated with respect to viscosity, acid number, size distribution, and stability. The particle size varied from less than 3 nm to above 8 nm representing polymers with molecular weight in the range of 3000–153,000. Lower molecular weight polymers were found to be unstable. Particle size measurements using dynamic light scattering technique indicated a normal distribution which corresponded to the molecular weight distribution of the copolymer. The statistical distribution of the acid groups in the polymer chains played a significant role in the stability of low molecular weight polymers.  相似文献   
125.
Objectives: Silver nanoparticles (AgNPs) with a size ranging from 7 to 70?nm were synthesized using the ascorbic acid-citrate seed-mediated growth approach at room temperature.

Methods: The 8?nm silver particles were prepared using gallic acid in alkaline conditions and used as seed to prepare AgNPs.

Results: The presence of ascorbic acid and citrate allows the regulation of size and size distribution of the nanoparticles. The increase in free silver ion-to-seed ratio (Ag+/Ag0) resulted in changes of particle shape from spherical to pseudo-spherical and minor cylindrical shape. Further, a repetitive seeding approach resulted in the formation of pseudo-spherical particles with higher polydispersity index and minor distributions of tetrahedral particles. Citrate-capped AgNPs were stable and did not agglomerate upon centrifugation. The effect of AgNPs on biofilm reduction was evaluated using static culture on 96-well microtiter plates. Results showed that AgNPs with the smallest average diameter were most effective in the reduction of Pseudomonas aeruginosa biofilm colonies, which accounted for 90% of removal.

Conclusion: The biofilm removal activities of the nanoparticles were found to be concentration-independent particularly for the concentration within the range of 80–200?µg/mL.  相似文献   
126.
Sulfamate (NHSO(3)(-)) groups are critically important structural elements of the glycosaminoglycans heparin and heparan sulfate (HS). Experimental conditions are presented for detection of the sulfamate (1)H NMR resonances in aqueous solution. NMR spectra reported for N-sulfoglucosamine (GlcNS) and the synthetic pentasaccharide drug fondaparinux demonstrate the broad utility of the sulfamate group (1)H chemical shifts to reflect differences in molecular structure. The sulfamate protons also provide an efficient route for detection of (15)N chemical shifts through proton-nitrogen correlations measured with the heteronuclear single quantum coherence (HSQC) experiment. The HSQC spectra of GlcNS, fondaparinux, and the low-molecular weight heparin enoxaparin illustrate the power of the (1)H and (15)N chemical shifts of the sulfamate NH groups for the structural characterization of heparin and HS.  相似文献   
127.
To improve the reliability and accuracy of tests used to measure emissions of volatile organic compounds (VOCs) from samples of interior building products, the National Institute of Standards and Technology (NIST) and Virginia Tech (VT) have created a program to develop reference materials with independently predictable emission rates. A diffusive reference material and associated mechanistic model have been developed and are undergoing extensive evaluation. As part of this process, a pilot inter-laboratory study (ILS) was conducted with four laboratories using a polymer material loaded with toluene as the reference source. Results showed the prototype material to be a relatively stable, homogeneous source with consistent emissions both within and between production batches. A comparison of toluene emission rates determined by the laboratories showed relative standard deviations as low as 9%, which are significantly lower than inter-laboratory variations for most previous ILS exercises with VOC sources. At a sample time of 48 h, the mean measured toluene emission rate for all four laboratories was within 1% of the model predicted value. The success of this pilot ILS is a key step toward being able to provide a VOC reference material for independent validation of VOC emission tests conducted in small chambers.  相似文献   
128.
We have shown that superparamagnetic iron oxide (Fe3O4) nanoparticles with a surface functionalization of dimercaptosuccinic acid (DMSA) are an effective sorbent material for toxic soft metals such as Hg, Ag, Pb, Cd, and Tl, which effectively bind to the DMSA ligands and for As, which binds to the iron oxide lattices. The nanoparticles are highly dispersible and stable in solutions, have a large surface area (114 m2/g), and have a high functional group content (1.8 mmol thiols/g). They are attracted to a magnetic field and can be separated from solution within a minute with a 1.2 T magnet. The chemical affinity, capacity, kinetics, and stability of the magnetic nanoparticles were compared to those of conventional resin based sorbents (GT-73), activated carbon, and nanoporous silica (SAMMS) of similar surface chemistries in river water, groundwater, seawater, and human blood and plasma. DMSA-Fe3O4 had a capacity of 227 mg of Hg/g, a 30-fold larger value than GT-73. The nanoparticles removed 99 wt% of 1 mg/L Pb within a minute, while it took over 10 and 120 min for Chelex-100 and GT-73 to remove 96% of Pb.  相似文献   
129.
In this paper we present first-order formulas for basic point-set topology, in an attempt to extend the mathematical range available for exploration with automated theorem-proving programs. We present topology definitions and sample lemmas both in first-order logic and in clausal form. We then illustrate some of the difficulties of these sample lemmas through a proof of a basic lemma in five parts.This work was supported by the Applied Mathematical Sciences subprogram of the Office of Energy Research, U.S. Department of Energy, under contract W-31-109-Eng-38, and by the Division of Educational Programs, Argonne National Laboratory.  相似文献   
130.
Meta-analysis (Hunter, Schmidt, & Jackson, 1982) of 50 assessment center studies containing 107 validity coefficients revealed a corrected mean and variance of .37 and .017, respectively. Validities were sorted into five categories of criteria and four categories of assessment purpose. Higher validities were found in studies in which potential ratings were the criterion, and lower validities were found in promotion studies. Sufficient variance remained after correcting for artifacts to justify searching for moderators. Validities were higher when the percentage of female assessees was high, when several evaluation devices were used, when assessors were psychologists rather than managers, when peer evaluation was used, and when the study was methodologically sound. Age of assessees, whether feedback was given, days of assessor training, days of observation, percentages of minority assessees, and criterion contamination did not moderate assessment center validities. The findings suggest that assessment centers show both validity generalization and situational specificity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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