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41.
Architecture and Physical Implementation of a Third Generation 65 nm, 16 Core, 32 Thread Chip-Multithreading SPARC Processor 总被引:1,自引:0,他引:1
Konstadinidis G.K. Tremblay M. Chaudhry S. Rashid M. Lai P.F. Otaguro Y. Orginos Y. Parampalli S. Steigerwald M. Gundala S. Pyapali R. Rarick L.D. Elkin I. Ge Y. Parulkar I. 《Solid-State Circuits, IEEE Journal of》2009,44(1):7-17
This third-generation Chip-Multithreading (CMT) SPARC processor consists of 16 cores with shared memory architecture and supports a total of 32 main threads plus 32 scout threads. It is targeted for high-performance servers, and is optimized for both single- and multi-threaded applications. The 396 mm2 chip is fabricated in an 11 metal layer 65-nm CMOS process and operates at a nominal frequency of 2.3 GHz, consuming a maximum power of 250 W at 1.2 V. This paper provides an overview of the architectural highlights and describes the physical implementation challenges and solutions including circuit innovations in memory arrays, register files, and floating-point hardware that boost the performance and circuit robustness with low area overhead. 相似文献
42.
Richard B Kreider Colin D Wilborn Lem Taylor Bill Campbell Anthony L Almada Rick Collins Mathew Cooke Conrad P Earnest Mike Greenwood Douglas S Kalman Chad M Kerksick Susan M Kleiner Brian Leutholtz Hector Lopez Lonnie M Lowery Ron Mendel Abbie Smith Marie Spano Robert Wildman Darryn S Willoughby Tim N Ziegenfuss Jose Antonio 《Journal of the International Society of Sports Nutrition》2010,7(1):1-43
Sports nutrition is a constantly evolving field with hundreds of research papers published annually. For this reason, keeping up to date with the literature is often difficult. This paper is a five year update of the sports nutrition review article published as the lead paper to launch the JISSN in 2004 and presents a well-referenced overview of the current state of the science related to how to optimize training and athletic performance through nutrition. More specifically, this paper provides an overview of: 1.) The definitional category of ergogenic aids and dietary supplements; 2.) How dietary supplements are legally regulated; 3.) How to evaluate the scientific merit of nutritional supplements; 4.) General nutritional strategies to optimize performance and enhance recovery; and, 5.) An overview of our current understanding of the ergogenic value of nutrition and dietary supplementation in regards to weight gain, weight loss, and performance enhancement. Our hope is that ISSN members and individuals interested in sports nutrition find this review useful in their daily practice and consultation with their clients. 相似文献
43.
44.
Saunders Jennifer Clare; McDonald Skye; Richardson Rick 《Canadian Metallurgical Quarterly》2006,20(2):224
The authors used affective modulation of the eyeblink startle response to examine the impact of traumatic brain injury (TBI) on emotional reactions to pictures. Participants were 13 individuals with severe TBI and 24 controls. Participants were presented with pictures that differed in affective valence (e.g., mutilated bodies, erotic couples, and household objects) while the eyeblink startle response to an acoustic probe was measured. Startle amplitude was used to assess valence of emotional response, and startle latency was used to index interest in the pictures. Subjective ratings of the affect and arousal elicited by the various pictures were also obtained. TBI impaired startle potentiation to unpleasant pictures but not startle attenuation to pleasant pictures. Further, subjective ratings indicated that TBI participants found unpleasant pictures less arousing than did controls. The results are consistent with recent evidence of differential impairment in negative versus positive emotions after TBI and are discussed in relation to 2 competing explanations of startle modulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Bruce Melville Rick van Ballegooy Sjoerd van Ballegooy 《Canadian Metallurgical Quarterly》2006,132(3):324-327
An experimental study of flow-induced failure of cable-tied blocks is presented. The particular failure mechanism studied is overturning and rolling up of the leading edge of a cable-tied block mat. Individual blocks were investigated also. The block size, flow depth, and block (mat) protrusion above the surrounding bed were systematically varied. The results are presented in terms of the critical dimensionless shear stress θc for block (mat) failure. A relationship between θc, block size and block protrusion, and flow depth is given. 相似文献
46.
Piperidine Alkaloids in Nitrogen Fertilized Pinus ponderosa 总被引:2,自引:0,他引:2
We fertilized individual, pole-size ponderosa pine trees at two low-quality sites and pine saplings at a relatively high-quality site, with ammonium nitrate. Six to 12 months later, we measured total %N and 2,6-disubstituted piperidine alkaloids in the foliage. The N additions raised foliar %N above deficiency levels (i.e., from 1.0–1.1% to 1.4–1.6%) at the low-quality sites, but did not elevate foliar %N in saplings at the higher quality site, where it was already (1.9%) well above critical levels. In control trees with foliar N below a threshold of 1.1%, we detected no more than trace levels of alkaloids, indicating that alkaloid production is highly constrained by N deficiency. The N additions increased mean concentrations of the predominant alkaloid, pinidine, at all three sites. Mean total alkaloid concentrations for fertilized trees at the two low-quality sites were 12 and 155 g/g dry wt higher than controls (relative increases of 12× and 4.5×, respectively). For saplings at the high-quality site, the mean total increased by 584 g/g dry wt (1.6×) with the N additions. Allocation of foliar N to alkaloids was highest in fertilized saplings (0.81%) compared to control saplings (0.53%). These findings demonstrate that foliar alkaloid concentrations can be increased by nitrogen fertilization of forest trees growing on both low- and high-quality sites. Fertilizing for the purpose of inhibiting potential herbivores may be more successful at higher quality sites where alkaloid levels are enhanced relative to food quality (foliar %N). 相似文献
47.
Logs from the base of Douglas fir (Pseudotsuga menziesii) trees cut in October 1993 were randomly assigned to one of three treatment groups: (1) wet logs—cut from the fallen tree and left exposed to rain, (2) dry logs—cut from the fallen tree, placed on blocks, and protected from rain under a plastic tent, and (3) crown logs—left attached to the fallen tree with its branches intact and exposed to rain. The following May, ethanol concentrations were highest in the phloem and sapwood of wet logs (0.24 and 0.35 mol/g fresh wt, respectively). Ethanol concentrations in tissues from dry and crown logs were similar to each other (ranging from 0.002 to 0.03 mol/g fresh wt), but were significantly lower than in wet logs. It appears that rain absorbed by the outer bark of wet logs creates a barrier to gas exchange between living tissues and the atmosphere, which facilitates the development of hypoxic conditions necessary for ethanol synthesis and accumulation. Branches on crown logs exposed to rain help maintain low ethanol concentrations in the log tissues; we discuss several potential mechanisms to explain this response. By early September, the densities of Gnathothrichus spp. gallery entrance holes were high on wet logs (21.5/m2) and low on dry (2.5/m2) and crown logs (5.8/m2), indicating their preference for logs with higher ethanol concentrations. Protecting logs from rain will significantly reduce ethanol concentrations and the density of ambrosia beetle galleries. Leaving branches attached to logs will produce similar results, but its effectiveness may vary depending on the environmental conditions. Host selection by secondary scolytid beetles that use ethanol as a kairomone can be manipulated and possibly managed by controlling the production of ethanol in the host resource. 相似文献
48.
Social reforms in American education are setting the stage for a paradigm shift in our nation's schools. The convergence of education and health care reform and the movement in the human services arena toward service integration models provide an unprecedented opportunity to redefine psychological services related to schools for the next century. Whereas school psychological services historically have been linked to changes in special education legislation, social reforms in education and health care that emphasize educational achievement and whole-child development offer promise for expanding and enhancing the roles of psychologists whose practices relate to schools and children. This article explores the foundations for change and highlights critical areas in which psychological practice in the schools may develop in the 1990s and beyond. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
Bosilevac JM Shackelford SD Fahle R Biela T Koohmaraie M 《Journal of food protection》2004,67(10):2248-2254
Acidified sodium chlorite (ASC) spray was evaluated at decreased dosages and application rates to determine its efficacy for reducing bacterial contamination on boneless beef trimmings used for production of raw ground beef products while maintaining desirable consumer qualities in the finished ground beef products. Two different applications of ASC (600 ppm applied at a rate of 1.3 oz/lb and 300 ppm applied at a rate of 1 oz/lb) were used to treat boneless beef trimmings before grinding. The effect of ASC treatment on 50/50 lean beef trimmings was greater than on 90/10 trimmings. ASC at 600 ppm reduced both the aerobic plate counts (APC) and Enterobacteriaceae counts (EBC) by 2.3 log CFU/g on 50/50 trimmings, whereas treatment with 300 ppm ASC reduced APC and EBC of 50/50 trimmings by 1.1 and 0.7 log CFU/g, respectively. Ground beef formulations of 90/10 and 73/27 were produced from the treated boneless beef trim and packaged in chubs and in modified atmosphere packaging. The efficacy of ASC spray treatment to inhibit APC and EBC over the shelf life of each ground beef product was monitored. The APC and EBC in ground beef chubs were reduced by 1.0 to 1.5 log CFU/g until day 20. The APC and EBC for products in modified atmosphere packaging were reduced 1.5 to 3.0 log CFU/g throughout their shelf life. Both decreased dosages of ASC were equally effective on 90/10 lean ground beef, but the 300 ppm ASC treatment was slightly better at reducing the EBC of 73/27 ground beef. The organoleptic qualities (color, odor, and taste) of the ground beef products treated with 300 ppm ASC were found to be superior to those treated with 600 ppm ASC. Our results indicated that decreased dosages of ASC reduce contamination and lengthen the shelf life of ground beef. Furthermore, the 300 ppm ASC treatment reduced bacterial counts while maintaining desirable organoleptic ground beef qualities. 相似文献
50.
Blakley R 《Applied optics》2004,43(22):4328-4333
A doublet of choice glasses may be located in the converging focal cone of the infinity-focused parabola to yield an aplanatic telescope or camera. The resulting angular field is limited by high astigmatism but is significantly larger than that of the coma-limited parabola. The spherical and chromatic aberrations are so well corrected and the coma so well balanced that the doublet may be used unaltered with a parabola of arbitrary focal length and speed with excellent results for the unvignetted rays. A second doublet nearer to the focus and designed independently of the first corrects the system's astigmatism while preserving its aplanaticism. It may also be designed for flattening the field. This arrangement may allow for greater flexibility in the placing of optical elements than does Wynne's triplet for modest-aperture systems. Equations are presented for choosing candidate glasses for the first doublet from the very limited manifold of solving glasses. 相似文献