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991.
Pérez-Edgar Koraly; Bar-Haim Yair; McDermott Jennifer Martin; Chronis-Tuscano Andrea; Pine Daniel S.; Fox Nathan A. 《Canadian Metallurgical Quarterly》2010,10(3):349
Behavioral inhibition (BI) is a temperament characterized in young children by a heightened sensitivity to novelty, social withdrawal, and anxious behaviors. For many children, these social difficulties dissipate over time. For others, patterns of social withdrawal continue into adolescence. Over time, attention biases to threat may influence the stability of BI and its association with social withdrawal, ultimately modulating the risk for anxiety disorders in BI children. However, we know relatively little about the cognitive processes that accompany BI and shape later socioemotional functioning. We examined the relations among BI in childhood, attention biases to threat in adolescence, and adolescent social withdrawal in a longitudinal study (N = 126, Mean age = 15 years). As has been reported in anxious adults, adolescents who were behaviorally inhibited as toddlers and young children showed heightened attention bias to threat. In addition, attention bias to threat moderated the relation between childhood BI and adolescent social withdrawal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Recent developments in technology, such as building information models (BIMs), immersive displays, and mobile computing tools, have enabled changes in the means and locations of communication throughout the building architecture, engineering, construction, and operation (AECO) industry. This paper presents the findings from an exploratory study regarding the planning of physical media for effective communication in conjunction with the developments in BIM use. While literature shows that there has been noticeable impact of physical media on communication, there has been little evidence of consistent and thorough planning and evaluation of media for investment or project level planning. The exploratory study identifies media synchronicity theory as a starting point for identifying the media needs by task for more effective planning of communication, as well as potential considerations unique to the AECO industry. The paper concludes with studies which have begun for planning more specific applications for BIM and media within AECO. 相似文献
993.
Rakesh Sohal Christian Walczyk Peter Zaumseil Dirk Wolansky Alexander Fox Bernd Tillack Hans-Joachim Müssig Thomas Schroeder 《Thin solid films》2009,517(16):4534-4539
This research is targeted to enhance the functionality of bipolar complementary metal-oxide-semiconductor by innovative concepts of embedded resistive random access memory (RRAM) cells integration in the back-end-of-line (BEOL) region. The material of our interest is tungsten oxide as an insulator in RRAM cells and we focussed on the growth and characterisation of closed tungsten oxide layers. In this materials science study, we investigated the tungsten oxidation process under BEOL constraints (< 450 °C). Thin films of tungsten oxide (6-50 nm) were prepared by oxidising, under an atmosphere of one bar oxygen, the chemical vapour deposited tungsten layers on TiN covered silicon wafers. The X-ray photoelectron spectroscopy investigations indicate that the stoichiometric WO3 grows after oxidation at 300 °C for an hour. The tungsten oxide layers prepared above 300 °C for longer than 15 min were non-stoichiometric. The X-ray diffraction investigations reveal the crystallisation of the WO3 layers in monoclinic phase above 350 °C when oxidised for longer than 30 min; above 400 °C the (001) growth texture becomes dominant. 相似文献
994.
R. Stamp P. Fox W. O’Neill E. Jones C. Sutcliffe 《Journal of materials science. Materials in medicine》2009,20(9):1839-1848
Porous structures are used in orthopaedics to promote biological fixation between metal implant and host bone. In order to
achieve rapid and high volumes of bone ingrowth the structures must be manufactured from a biocompatible material and possess
high interconnected porosities, pore sizes between 100 and 700 μm and mechanical strengths that withstand the anticipated
biomechanical loads. The challenge is to develop a manufacturing process that can cost effectively produce structures that
meet these requirements. The research presented in this paper describes the development of a ‘beam overlap’ technique for
manufacturing porous structures in commercially pure titanium using the Selective Laser Melting (SLM) rapid manufacturing
technique. A candidate bone ingrowth structure (71% porosity, 440 μm mean pore diameter and 70 MPa compression strength) was
produced and used to manufacture a final shape orthopaedic component. These results suggest that SLM beam overlap is a promising
technique for manufacturing final shape functional bone ingrowth materials. 相似文献
995.
Fox B. Jennings L.S. Zomaya A.Y. 《IEEE transactions on bio-medical engineering》1999,46(10):1199-1206
The principle of virtual work is used to derive the Euler-Lagrange equations of motion in order to describe the dynamics of multibody android systems. The constrained variational equations are in fact differential-algebraic equations of high index and are cast as ordinary differential equations through differentiation of the constraint equations. The integration routine LSODAR and the fourth-order Runge-Kutta method are used to compute the generalized coordinates, their time derivatives and the body forces of two android models. The graphs of the constraint forces reveal the whiplash effect on the neck and that the stiffness of both multibody systems is due to large magnitude impulsive forces experienced by many bodies simultaneously. 相似文献
996.
Hydrogeologic modeling for permeable reactive barriers. 总被引:3,自引:0,他引:3
The permeable reactive barrier technology for in situ treatment of chlorinated solvents and other groundwater contaminants is becoming increasingly popular. Field scale implementation of this and other in situ technologies requires careful design based on the site-specific hydrogeology and contaminant plume characteristics. Groundwater flow modeling is an important tool in understanding the hydraulic behavior of the site and optimizing the reactive barrier design. A combination of groundwater flow modeling and particle tracking techniques was used to illustrate the effect of hydraulic conductivity of the aquifer and reactive media on key permeable barrier design parameters, such as the capture zone width, residence time, flow velocity, and discharge. Similar techniques were used to illustrate the modeling approach for design of different configurations of reactive barriers in homogeneous and heterogeneous settings. 相似文献
997.
Patrick J. Fox 《Canadian Metallurgical Quarterly》1999,125(10):847-867
This paper presents graphical solution charts for 1D consolidation of a single homogeneous layer of normally consolidated clay under a surcharge load. Cast in dimensionless form, the charts include the effects of vertical strain, self-weight, and decreasing compressibility and hydraulic conductivity during the consolidation process. To estimate total settlement, the user must specify the initial layer thickness, compression index, initial void ratio at the midheight of the layer, and initial and final effective stress conditions at the top of the layer. To estimate the rate of settlement and distribution of excess pore pressure, boundary drainage conditions and the initial hydraulic conductivity at the midheight of the layer are also required. As a design tool, the charts can be used to make preliminary estimates of settlement and excess pore pressure with fewer restrictive assumptions than for conventional theory. The charts can also be used to verify solutions obtained from numerical analyses. Furthermore, the charts are educational in that they illustrate the effect of different variables on the consolidation process. Using the solution charts, estimated values for settlement are in good agreement with field measurements for a well-documented case study. Estimated and measured values for excess pore pressure are in reasonable agreement during the middle stages of consolidation but are in lesser agreement during the early and later stages. 相似文献
998.
Tomasz Haupt Erol Akarsu Geoffrey Fox Wojtek Furmanski 《Future Generation Computer Systems》1999,15(5-6):735-743
Programming tools that are simultaneously sustainable, highly functional, robust and easy to use have been hard to come by in the HPCC arena. This is partially due to the difficulty in developing sophisticated customized systems for what is a relatively small part of the worldwide computing enterprise. Thus, we have developed a new strategy – termed High Performance Commodity Computing (HPCC) [G. Fox, W. Furmanski, HPCC as high performance commodity computing, in: I. Foster, C. Kesselman (Eds.), Building National Grid, http://www.npac.syr.edu/users/gcf/HPcc/HPcc.html] – which builds HPCC programming tools on top of the remarkable new software infrastructure being built for the commercial web and distributed object areas. We add high performance to commodity systems using multi-tier architecture with Globus metacomputing toolkit as the backend of a middle-tier of commodity web and object servers. We have demonstrated the fully functional prototype of WebFlow during Alliance’98 meeting. 相似文献
999.
A heuristic method of seeding the initial population of a Genetic Algorithm (GA) is described, which enables better solutions
to discrete truss optimisation problems to be found within a shorter time period, and with a negligible increase in computational
effort (compared with the simple GA). The seeding method is entirely automatic, and makes use of the problem-specific routines
used to calculate fitness, already present within the GA. The GA models natural, biological evolution as a means of producing
a ‘good’ solution to a problem. The GA described here is implemented in various versions. The differences between each version
are in the selection procedure and/or the generation of the initial population. To compare the effectiveness of each strategy
the GA variants are applied to four example problems. 相似文献
1000.