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51.
William L. Carlson 《Accident; analysis and prevention》1979,11(2):137-153
Automobile crash injury was analyzed using data from the Crash Performance Injury Report (CPIR) for crashes which occurred since 1 January 1970 involving 1969 or newer cars, vans and pickup trucks. An injury prediction model was developed using delta V, vehicle weight, occupant age, seating position, crash configuration, and restraint usage to predict expected AIS. Expected AIS was then used to estimate the probability of death and severe injury. The model estimates were found to approximate the observed probability of death and severe injury from the National Crash Severity Study (NCSS) data file. 相似文献
52.
It has been more than four years since the last of my infrequent editorials in the International Journal of Stress Management (IJSM) and nearly a decade since my first (Carlson, 1998b). I am writing to you at this time first to inform you of a change in editorship, then to summarize a few high points of the past 10 years of IJSM as they relate to its management and future. My focus will be on matters dear to journal editors and useful to submitters and subscribers concerning submissions, content, and editorial activity, since such issues determine journal policy and direction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
54.
This study examines how problem solvers distribute working memory demands over internal and external resources. Participants recorded notes while performing an arithmetic task. They recorded a majority of intermediate results and labeled many of those results (e.g., "C?=?10"). When more effort was required to take notes, participants recorded fewer results. Participants with a consistent goal structure recorded fewer results and with practice labeled fewer recorded results than those with varied goal structures. When notes were displayed in a consistent spatial arrangement participants labeled fewer recorded results than when notes appeared in varied locations. These findings indicate that individuals use explicit and implicit strategies for indexing intermediate results. The data support the view that individuals flexibly distribute working memory over internal and external resources in response to situational cost-benefit considerations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
56.
John A. Johnson Nancy M. Carlson Layman A. Lott 《Journal of Nondestructive Evaluation》1987,6(3):147-157
Ultrasonic methods are being developed for sensing and control of high temperature material processes such as welding and solidification. One of the problems in these methods is the distortion of the sound field caused by the change in material properties due to temperature gradients. This paper describes a ray-tracing method for calculating the effects of temperature on ultrasonic propagation in such systems. In the ray-tracing method, the material is conceptually divided into a number of plane layers. The refraction at each layer boundary is calculated from Snell's law using the sound speeds determined from the temperatures of the adjacent layers. The time required for an ultrasonic pulse to traverse each layer is also calculated, allowing the determination of the total time along a particular path. The method is applied to calculating the time of arrival of echoes from various interfaces around a molten weld pool. 相似文献
57.
Mehmet Uz D. K. Rehbein O. N. Carlson 《Metallurgical and Materials Transactions A》1986,17(11):1955-1966
Thermotransport experiments were performed on two-phase V-C and Nb-C alloys for various times, temperature ranges, and compositions.
A one-phase region develops in the hotter portion of the sample accompanied by an increase in carbide concentration in the
colder region. A mathematical equation in which the direction of transport is described by the sum of the heat of solution,A―H, and the heat of transport,Q*, was fitted to the experimental data for all of the alloys studied. No evidence was found to support the physical motion
of the carbide particles predicted by some models. On the assumption that local equilibrium exists between the particles and
the matrix, points on the V-C solvus were determined from the temperature corresponding to the one-phase/two-phase interface
in the different experiments. The solid solubility for carbon in vanadium was determined to be log C (at. pct C) = 2.918 -
4536/T with a heat of solution of 86.8 ± 2.9 kJ/mol.
Formerly a Graduate Research Assistant, Ames Laboratory, Iowa State University 相似文献
58.
Carlson N.W. Evans G.A. Liew S.K. Kaiser C.J. 《Lightwave Technology, Journal of》1989,7(10):1520-1524
The electrooptic switching properties of injection-coupled coherent two-dimensional grating-surface-emitting (GSE) laser arrays with multiple gain sections and quantum-well active layers are discussed. Within such an array of injection-coupled GSE lasers, a single gain section can act as an intracavity saturable loss element that can modulate the output of the entire array. Experimental results demonstrate efficient subnanosecond switching of high-power GSE laser arrays by operating only one gain section as an intracavity loss modulator 相似文献
59.
Manganese (Mn) in a drinking water distribution system can cause multiple aesthetic problems including discolored water and fouling or scaling of fixtures. Oxidation and solid-liquid separation processes are typically employed at a treatment plant to limit the concentration of Mn entering the distribution system. Potassium permanganate (KMnO4) is commonly used to oxidize the manganous ion (Mn+2) to manganese oxide (MnO2). In this study, a mechanistic model is applied to the oxidation of manganese at a treatment plant. Literature kinetic constants (determined with artificial water) are compared with the values obtained for the plant's natural water. The solution and surface phase oxidation rate constants determined with the natural water are two to six orders of magnitude less than those determined with the artificial water. The reduced oxidation rate in the natural water is attributed to the presence of dissolved organic matter, which can exert a competitive demand on the oxidant and interfere with the oxidation by complexing Mn+2. The development of an additional rate constant for the oxidation of dissolved organic matter improves the modeling results for KMnO4 concentration versus time, but only marginally explains the Mn+2 oxidation rate differences. 相似文献
60.
Neubert Mitchell J.; Kacmar K. Michele; Carlson Dawn S.; Chonko Lawrence B.; Roberts James A. 《Canadian Metallurgical Quarterly》2008,93(6):1220
In this research, the authors test a model in which the regulatory focus of employees at work mediates the influence of leadership on employee behavior. In a nationally representative sample of 250 workers who responded over 2 time periods, prevention focus mediated the relationship of initiating structure to in-role performance and deviant behavior, whereas promotion focus mediated the relationship of servant leadership to helping and creative behavior. The results indicate that even though initiating structure and servant leadership share some variance in explaining other variables, each leadership style incrementally predicts disparate outcomes after controlling for the other style and dispositional tendencies. A new regulatory focus scale, the Work Regulatory Focus (WRF) Scale, also was developed and initially validated for this study. Implications for the results and the WRF Scale are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献