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71.
Julie A. Rosen 《Natural Gas \u0026amp; Electricity》2015,31(11):25-29
For nearly a century, the Migratory Bird Treaty Act has been a tool used by the federal government to protect migratory bird species.1 相似文献
72.
Erfan Khodabandeh Hesam Moghadasi Mohsen Saffari Pour Mikael Ersson P r G. J nsson Marc A. Rosen Alireza Rahbari 《中国化学工程学报》2020,28(4):1029-1038
This research investigates a numerical simulation of swirling turbulent non-premixed combustion. The effects on the combustion characteristics are examined with three turbulence models: namely as the Reynolds stress model, spectral turbulence analysis and Re-Normalization Group. In addition, the P-1 and discrete ordinate (DO) models are used to simulate the radiative heat transfer in this model. The governing equations associated with the required boundary conditions are solved using the numerical model. The accuracy of this model is validated with the published experimental data and the comparison elucidates that there is a reasonable agreement between the obtained values from this model and the corresponding experimental quantities. Among different models proposed in this research, the Reynolds stress model with the Probability Density Function (PDF) approach is more accurate (nearly up to 50%) than other turbulent models for a swirling flow field. Regarding the effect of radiative heat transfer model, it is observed that the discrete ordinate model is more precise than the P-1 model in anticipating the experimental behavior. This model is able to simulate the subcritical nature of the isothermal flow as well as the size and shape of the internal recirculation induced by the swirl due to combustion. 相似文献
73.
Rosen R 《Computers & chemistry》1994,18(3):347-352
The following work compares two different ways of fractionating or abstracting from an organism: (a) a Mendelian way, which views the organism as a discrete bundle of phenotypic characters, each controlled by a corresponding genetic "factor", and (b) as a bundle of particulate molecular fractions, as envisaged by molecular biology. It is generally believed that the latter completely subsumes the former, and that it further serves to subsume all of biology into contemporary physics. We argue herein that the first of these assertions, if true at all, does not follow from an initial positing of an identity between the Mendelian gene and DNA sequence, and may well be false in general. In either case, the second assertion becomes false as well. This has profound consequences, not only for biology, but for the physics which is presumed to underlie it; it constitutes a part of the "new physics" which Erwin Schr?dinger, in a famous essay [(1944) What is Life? Cambridge University Press, Cambridge], argued was inherent in biology. 相似文献
74.
Transfer matrix models have been frequently used to analyze the structural behavior of rods, including curved and pretwisted ones. The advantages of these models include their relative simplicity, numerical efficiency and ease of implementation. Previous investigations did not include nonlinear analyses of curved rods that undergo large deformations. The present paper describes a nonlinear transfer matrix model of curved and pretwisted rods, which is capable of analyzing very large spatial deformations. The rod is divided into segments. A body system of coordinates is attached to each segment. This system translates and rotates with the segment during the deformation. If the segments are kept small enough, the local deformations of each segment, relative to its body system of coordinates, are small. The segments’ systems of coordinates rotate relative to their neighbors and if this rotation is dealt with properly, large rotations and displacement of the curved rod can be analyzed. In spite of its nonlinear nature, the model remains relatively simple and efficient. The new model is used to solve a few problems and the results show very good agreement with other analytical, finite-element, and experimental results. 相似文献
75.
The large volume of data associated with social networks hinders the unaided user from interpreting network content in real time. This problem is compounded by the fact that there are limited tools available for enabling robust visual social network exploration. We present a network activity visualization using a novel aggregation glyph called the clyph. The clyph intuitively combines spatial, temporal, and quantity data about multiple network events. We also present several case studies where major network events were easily identified using clyphs, establishing them as a powerful aid for network users and owners. 相似文献
76.
Univ.-Prof. DI Dr. Helmut Habersack DI Marlene Haimann Ass. Prof. Dr. Sándor Baranya Prof. Dr. János Józsa Mag. Angelika Riegler Dr Christine Sindelar DI Marcel Liedermann Johanna Ficsor Gabriella Mohácsiné Simon HR DI Dr. Michael Hengl 《?sterreichische Wasser- und Abfallwirtschaft》2014,66(9-10):340-347
The multiple uses of the Danube River for navigation, hydropower production and as a drinking water supply influence its ecological quality. Flow restrictions due to regulation as well as impacts on the sediment regime such as retention in the catchment area and interruption of the sediment continuum result in changes of the hydromorphological structures and can produce major problems in the context of sediment management. In light of these facts, cross-border investigations of sediment transport at the Danube River are called for. As there are no uniform research approaches shared by Austria and Hungary, the EU-funded project SEDDON (Sediment Research and Management at the Danube River) aims to compare different monitoring and modeling techniques used to determine sediment transport, and to develop mutual solutions. Further, the laboratory equipment currently used for hydraulic model experiments is evaluated and a research channel with a free flowing discharge of up to 10 m3/s without pumping will be constructed, allowing large-scale joint laboratory tests concerning sediment to be performed. 相似文献
77.
Rosen Craig S.; Murphy Ronald T.; Chow Helen C.; Drescher Kent D.; Ramirez Gil; Ruddy Robyn; Gusman Fred 《Canadian Metallurgical Quarterly》2001,38(2):233
Notes that recovery from combat-related posttraumatic stress disorder (PTSD) is often complicated by unacknowledged problems with alcohol and anger. 102 males combat veterans (aged 42–63 yrs) entering a residential PTSD rehabilitation program completed University of Rhode Island Change Assessment and process-of-change questionnaires based on J. O. Prochaska and C. C. DiClemente's transtheoretical model (TTM; J. O. Prochaska et al, 1992). Separate assessments were made for alcohol abuse and anger control. Four motivational subtypes were identified for both problems. Motivation to change alcohol problems was independent of that for anger. Relative to less-motivated peers highly motivated patients were more like to spontaneously identify alcohol or anger as problems in their life and made greater use of change strategies specified by the TTM. These results support extension of the TTM to anger management and to PTSD management. Treatment implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Multitasking across generations: Multitasking choices and difficulty ratings in three generations of Americans 总被引:1,自引:0,他引:1
L. Mark Carrier Nancy A. Cheever Larry D. Rosen Sandra Benitez Jennifer Chang 《Computers in human behavior》2009
This study investigated whether changes in the technological/social environment in the United States over time have resulted in concomitant changes in the multitasking skills of younger generations. One thousand, three hundred and nineteen Americans from three generations were queried to determine their at-home multitasking behaviors. An anonymous online questionnaire asked respondents to indicate which everyday and technology-based tasks they choose to combine for multitasking and to indicate how difficult it is to multitask when combining the tasks. Combining tasks occurred frequently, especially while listening to music or eating. Members of the “Net Generation” reported more multitasking than members of “Generation X,” who reported more multitasking than members of the “Baby Boomer” generation. The choices of which tasks to combine for multitasking were highly correlated across generations, as were difficulty ratings of specific multitasking combinations. The results are consistent with a greater amount of general multitasking resources in younger generations, but similar mental limitations in the types of tasks that can be multitasked. 相似文献
79.
An approach is suggested for the cost-effective systematic design of product on-board diagnostics that allow simple and complex appliances to diagnose or predict failures within themselves. This methodology differs from other current less formal approaches in that it encourages a wholly integrated design philosophy. Trends indicate that on-board diagnostic capabilities will become much more important in both the eyes of the consumer and the manufacturer in years to come. As such, the lack of a formal approach could represent a significant design bottleneck. The approach offered represents a meaningful first step in avoiding such a bottleneck. Furthermore, the technique can be used for evaluation and retrofit of diagnostics on existing products. Relevant background regarding machine self-diagnostics is presented, and future research needs are identified. 相似文献
80.
Security and encryption optical systems based on a correlator with significant output images 总被引:12,自引:0,他引:12
An improved optical security system based on two phase-only computer-generated masks is proposed. The two transparencies are placed together in a 4f correlator so that a known output image is received. In addition to simple verification, our security system is capable of identifying the type of input mask according to the corresponding output image it generates. The two phase masks are designed with an iterative optimization algorithm with constraints in the input and the output domains. A simulation is presented with the resultant images formed by the two phase-only elements. Various mask combinations are compared to show that a combination is unique and cannot be duplicated. This uniqueness is an advantage in security systems. 相似文献