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61.
Powder Metallurgy and Metal Ceramics - In this study, different heat treatment regimes, such as sintering, sintering with low-pressure cementation, and only low-pressure cementation were applied to... 相似文献
62.
63.
高容量移动应用的NOR闪存和NAND闪存 总被引:1,自引:0,他引:1
Francois Kaplan 《今日电子》2006,(3):60-61
高速数据传输网络和多媒体服务的大量部署使得具有更大的存储量成为新型手机和3G手机共有的要素。这些手机的存储量有望超过1Gb,而低端3G手机的存储能力将军少是32Mb。 相似文献
64.
E. Tel C. Durgu A. Aydın M. H. Bölükdemir A. Kaplan Ş. Okuducu 《Journal of Fusion Energy》2009,28(4):377-384
In the next century the world will face the need for new energy sources. Nuclear fusion can be one of the most attractive
sources of energy from the viewpoint of safety and minimal environmental impact. Fusion will not produce CO2 or SO2 and thus will not contribute to global warming or acid rain. Achieving acceptable performance for a fusion power system in
the areas of economics, safety and environmental acceptability, is critically dependent on performance of the blanket and
diverter systems which are the primary heat recovery, plasma purification, and tritium breeding systems. Tritium self-sufficiency
must be maintained for a commercial power plant. The hybrid reactor is a combination of the fusion and fission processes.
For self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. So working out the systematics
of (n, t) reaction cross-sections are of great importance for the definition of the excitation function character for the given reaction
taking place on various nuclei at energies up to 20 MeV. In this study, we have calculated non-elastic cross-sections by using
optical model for (n, t) reactions at 14–15 MeV energy. We have investigated the excitation function character and reaction Q-values depending on the asymmetry term effect for the (n, t) reaction cross-sections. We have obtained new coefficients for the (n, t) reaction cross-sections. We have suggested semi-empirical formulas including optical model nonelastic effects by fitting
two parameters for the (n, t) reaction cross-sections at 14–15 MeV. We have discussed the odd–even effect and the pairing effect considering binding energy
systematic of the nuclear shell model for the new experimental data and new cross-sections formulas (n, t) reactions developed by Tel et al. We have determined a different parameter groups by the classification of nuclei into even–even,
even–odd and odd–even for (n, t) reactions cross-sections. The obtained cross-section formulas with new coefficients have been discussed and compared with
the available experimental data. 相似文献
65.
Integration of Stiff Graphene and Tough Silk for the Design and Fabrication of Versatile Electronic Materials
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Shengjie Ling Qi Wang Dong Zhang Yingying Zhang Xuan Mu David L. Kaplan Markus J. Buehler 《Advanced functional materials》2018,28(9)
The production of structural and functional materials with enhanced mechanical properties through the integration of soft and hard components is a common approach to Nature's material design. However, directly mimicking these optimized design routes in the lab for practical applications remains challenging. For example, graphene and silk are two materials with complementary mechanical properties that feature ultrahigh stiffness and toughness, respectively. Yet, no simple and controllable approach is developed to homogeneously integrate these two components into functional composites, mainly due to the hydrophobicity and chemical inertness of graphene. In this study, well‐dispersed and highly stable graphene/silk fibroin (SF) suspension systems are developed, which are suitable for processing to fabricate polymorphic materials, such as films, fibers, and coatings. The obtained graphene/SF nanocomposites maintain the electronic advantages of graphene, and they also allow tailorable mechanical performance to form including ultrahigh stretchable (with a strain to failure to 611 ± 85%), or high strength (339 MPa) and high stiffness (7.4 GPa) material systems. More remarkably, the electrical resistances of these graphene/SF materials are sensitive to material deformation, body movement, as well as humidity and chemical environmental changes. These unique features promise their utility as wearable sensors, smart textiles, intelligent skins, and human–machine interfaces. 相似文献
66.
Stachowski Alicia A.; Kaplan Seth A.; Waller Mary J. 《Canadian Metallurgical Quarterly》2009,94(6):1536
Organizations increasingly rely on teams to respond to crises. While research on team effectiveness during nonroutine events is growing, naturalistic studies examining team behaviors during crises are relatively scarce. Furthermore, the relevant literature offers competing theoretical rationales concerning effective team response to crises. In this article, the authors investigate whether high- versus average-performing teams can be distinguished on the basis of the number and complexity of their interaction patterns. Using behavioral observation methodology, the authors coded the discrete verbal and nonverbal behaviors of 14 nuclear power plant control room crews as they responded to a simulated crisis. Pattern detection software revealed systematic differences among crews in their patterns of interaction. Mean comparisons and discriminant function analysis indicated that higher performing crews exhibited fewer, shorter, and less complex interaction patterns. These results illustrate the limitations of standardized response patterns and highlight the importance of team adaptability. Implications for future research and for team training are included. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Black soybean is a potential functional food ingredient with high anthocyanin content, but the ability to maintain anthocyanin content under dry heat processing has not been reported. This study investigated the effects of soybean seed coat colour and baking time–temperature combinations on the extractable antioxidant properties of a soy cracker food model. Crackers prepared with black soybeans had significantly higher TPC, total isoflavones, and peroxyl, hydroxyl, and ABTS+ radical scavenging abilities than their yellow counterparts, at all time–temperature combinations. Cyanidin-3-glucoside (C3G) was detected only in black soybean crackers, and all baking treatments significantly decreased C3G. The greatest losses occurred at the low temperature × long time and high temperature × short time, the smallest loss with moderate temperature × short/medium time. The high temperature treatment altered phenolic acid and isoflavone profiles; however, total isoflavones were unaffected. Overall results suggest that moderate baking temperature at minimal time may best preserve anthocyanin and other phenolics in baked black soybean crackers. 相似文献
68.
The nuclear data on (α, xn) reactions are very important in the fields of radiation shielding, long-term safe handling of spent fuel and spallation neutron-production. In this study, neutron-production cross sections have been calculated for some target nuclei such as 65Cu and 209Bi. Hybrid model and geometry dependent hybrid model have been used to calculate the pre-equilibrium neutron-production cross sections. The mean free path parameter’s effect for (α, xn) neutron-production cross section has been examined. The obtained results have been discussed and compared with the available experimental data. 相似文献
69.
70.
B. Z. Kaplan D. Yardeni 《International Journal of Circuit Theory and Applications》1991,19(3):309-315
The paper treats the development of a non-linearly stabilized oscillator model for generating four sine waves in quadrature. the treatment appears important although quadrature signals can also be generated by a well-known twophase oscillator. the latter generates only two of the signals needed in a four-phase system, but the rest of the phases signals could nevertheless be generated by simply inverting the two existing signals. For certain applications, however, the generation of all four signals in a completely cyclic and symmetrical manner is preferable. This method of generation is dealt with in the present paper. A previous paper of ours has treated a system of a similar objective. the present system, however, is much simpler. This simplicity is manifested not only through the mathematical representation but also when an electronic realization of the system is considered. the present model realization appears considerably less expensive, since the number of necessarily non-linear operations is much reduced. This reduction is due to the fact that the non-linearly stabilized model imbeds a ‘partially conservative’ linear oscillator. the concept of ‘partial conservativity’ has been introduced recently. the present work treats comprehensively the advantages that are gained by imbedding a partially conservative oscillator. 相似文献