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排序方式: 共有1168条查询结果,搜索用时 31 毫秒
91.
The influence of recycling on the impact damage resistance of recycled carbon fiber‐reinforced polymer (CFRP) composites was investigated using low‐velocity impact and compression after impact (CAI) tests. The relationships among load, force, and time were analyzed to gain insight into the damage characteristics of three types of composite laminate: virgin CF‐reinforced polymer (V‐CFRP), recycled CF‐reinforced polymer (R‐CFRP), and treated recycled CF‐reinforced polymer (TR‐CFRP). Special emphasis was placed on evaluating the extent of damage and the residual mechanical properties as affected by three different fiber surface states. Substantial differences were noted in the shape, area, and damage mode of impact using ultrasonic c‐scanning, photography, and scanning electron microscopy (SEM). V‐CFRP indicated significant improvement in impact damage resistance in the form of less damage, higher residual strength, and greater shear failure angle. Damage resistance was improved up to 80% of V‐CFRP by surface cleaning while R‐CFRP is 50% of V‐CFRP. Shear failure angle of 16° was attained from R‐CFRP and it was increased to 24° when the recycled fibers were cleaned. The result of SEM showed that there was less delamination of TR‐CFRP compared with R‐CFRP. This work proves that the low‐velocity impact response of recycled composites can rival that of virgin composites, while providing a basis for future applications of recycled carbon in many fields. POLYM. COMPOS., 35:1494–1506, 2014. © 2013 Society of Plastics Engineers 相似文献
92.
Shimizu M Miyashita K Kitagaki H Ito K Shimoi H 《Journal of Bioscience and Bioengineering》2005,100(6):678-680
Sake yeasts are used for sake brewing and have a crucial role in the quality of sake, since they produce not only ethanol but also various compounds that provide sake flavors. Therefore, the appropriate selection and monitoring of a strain used in sake mash is important. However, the identification of specific sake yeast strains has been difficult, because sake yeasts have similar characteristics in taxonomic and physiological analyses. We found amplified fragment length polymorphisms (AFLPs) in the PCR products of the AWA1 gene of sake yeast strains. The AWA1 gene encodes a cell wall protein that is responsible for foam formation in sake mash. This polymorphism of the AWA1 gene can be used for the identification of sake yeast strains. 相似文献
93.
Toru Hayano Kiyoshi Ohishi Toshimasa Miyazaki Daiichi Koide Haruki Tokumaru 《Electrical Engineering in Japan》2009,166(1):82-90
This paper proposes a new force sensorless robust tracking servo system, which detects and suppresses both the periodic disturbance and the sudden disturbance without force sensor. The proposed system estimates both the periodic disturbance and the sudden disturbance and the sudden disturbance by using a new sudden disturbance observer and the memory of tracking error. In the proposed system, the influence of sudden disturbance is suppressed by the proposed sudden disturbance observer. On the other hand, the influence of periodic disturbance is suppressed by means of ZPET feed‐forward servo system. The experimental results point out that the proposed tracking servo system has a precise tracking response against both the periodic disturbance and the sudden disturbance. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(1): 82–90, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20614 相似文献
94.
Kiyoshi Kusabiraki Shigeoki Saji Tomoya Tsutsumi 《Metallurgical and Materials Transactions A》1999,30(8):1923-1931
A Ni-18Cr-16Fe-5Nb-3Mo alloy (a modified alloy 718, referred to herein as 718M), in which the γ″ phase is the only precipitation-strengthening phase, was made by substituting most of the aluminum and titanium in INCONEL
718 with niobium. The specimens of alloy 718M were solid-solution heat treated, aged at 1033 to 1073 K for up to 360 ks, and
cold rolled to a reduction of 10 to 15 pct at room temperature. After subsequent annealing heat treatments, at the same temperatures
used for aging, the morphological and structural changes of the γ″ precipitates were investigated by transmission electron microscopic observation using carbon extraction replicas. Although
stacking faults were not noticed in the γ″ precipitates extracted from the aged 718M alloy, stacking faults introduced in the {112}
γ″
planes by cold rolling of the samples were confirmed. The stripelike contrast due to the stacking faults becomes less clear
with increasing annealing time. With longer annealing times, necking occurs between the stripes, which eventually separate
into plural particles. The selected-area electron diffraction (SAED) patterns of the cold-rolled and annealed particles show
that the metastable γ″ precipitates with stacking faults are transformed gradually into a stable δ phase. In this article, we discuss the basis of morphological and structural changes in detail.
INCONEL is a trademark of INCO Alloys International, Inc., Huntington, WV. 相似文献
95.
Linhua Liu Toshihiro Isobe Kiyoshi Okada Akira Nakajima 《Materials Research Bulletin》2011,46(2):175-184
The respective influences of calcination, drying methods, and washing conditions on the morphologies, surface properties, and photocatalytic activities of TiO2 powders prepared from acid treatments of BaTiO3 were investigated. Rutile powder was obtained using the treatment under strong acid conditions. It possesses a bundle-like shape and comprises rutile nanorods. After calcination, characteristic voids were observed in the particles. Anatase powder was obtained by adjusting pH values of a BaTiO3 suspension to 2.5-3. Drying at 110 °C engendered the formation of spheroidal anatase, although freeze-dried anatase particles assembled into a flake-like shape. The freeze-dried samples show lower crystallinity. With grafting Cu ions, rutile exhibited better photocatalytic performance for the decomposition of gaseous 2-propanol (IPA) under visible light, although it did not work effectively for anatase. 相似文献
96.
Motoyuki Sugano Hideyoshi Andoh Masafumi Tsubosaka Keiki Tanaka Katsumi Hirano Kiyoshi Mashimo 《Fuel》2009,88(12):2437-2441
It is well known that the amount of waste tyre increases every year, and a numerous amount of waste tyre is landfilled or dumped all over the world, which causes environmental problems, such as destruction of natural places and the risk of fires. Coprocessing waste tyre and coal is considered as one of the effective processing methods of both materials. Upon coprocessing lower rank coal (Wyoming, C; 68%) with waste tyre, the synergistic effects to upgrading, such as the increase of oil yield and the decrease of residue yield, were appeared. However, the synergistic effects were not observed on coprocessing two kinds of higher rank coals with waste tyre. The reactions of coal with benzophenone were carried out to discuss the hydrogen donatability of coal. Conversion of benzophenone to diphenylmethane on the reaction with Wyoming coal was higher than those of higher rank coals. Accordingly, it was considered that the synergistic effects to upgrading upon coprocessing Wyoming coal with waste tyre were obtained owing to the enhancement of stabilization of radicals from tyre and Wyoming coal through the hydrogen donation from both tyre and Wyoming coal. The effects of reaction temperature and the amount of solvent upon coprocessing Wyoming coal with waste tyre were also discussed in this study. 相似文献
97.
Kiyoshi Goto Bernard B. Argent William E. Lee 《Journal of the American Ceramic Society》1997,80(2):461-471
Microstructural analysis of MgO—MgAl2 O4 refractory bricks corroded at 1400–1450°C by calcium aluminosilicate slag reveals secondary spinel, monticellite, merwinite, and MgO as microscopic corrosion products, generally forming in this sequence as the brick is penetrated. The secondary spinel forms an incomplete layer close to (but not at) the MgO grain. Thermodynamic calculations are used to support a detailed model of the corrosion mechanism. 相似文献
98.
Quaternization of trans-dipyridylporphyrin with 1,4-butaneditrifluoromethane-sulfonate affords new polyionenes containing porphyrin units in the
main chain. The polymers exhibit chemical and electrochemical reversible redox activities. Weitz-type two-step redox processes
similar to those of viologens account for the redox properties of the polymers.
Received: 26 November 1996/Revised: 24 January 1997/Accepted: 10 February 1997 相似文献
99.
Hideki Hyuga Mark I. Jones Kiyoshi Hirao Yukihiko Yamauchi 《Journal of the American Ceramic Society》2004,87(5):894-899
Si3 N4 /carbon fiber composites have been produced with and without seeding by an extrusion and sintering process. In both cases the carbon fibers were aligned along the direction of extrusion, but the Si3 N4 grains were only aligned in the seeded material. The mechanical properties of the specimens showed anisotropy with respect to the grain alignment, with both strength and toughness being highest in the direction parallel to the extruding direction. In this direction the seeded specimen, where both the Si3 N4 grains and the carbon fibers were aligned, showed both higher fracture toughness and higher fracture strength than the nonseeded specimen where only the fibers were aligned. 相似文献
100.
Takeshi Yanagisawa Takeshi Kojima Tadamasa Koyanagi Kiyoshi Takahisa Kuniomi Nakamura 《Microelectronics Reliability》2002,42(2):219-223
Changes in the characteristics of CuInGaSe2 solar cells in response to light irradiation were investigated. Then these changes, which suggest long-term degradation, were clarified using the measurement technique by feeble light. The thin-film cell of this type is considered to be “ever stable”. A stable result over the short term was also obtained in the light accelerated test of 2-SUN performed in this experiment. On the other hand, it was found that the characteristics measured with feeble light show a remarkable change over time. As a result of measuring at 0.065–105 mW/cm2 light intensity, the change rate of cell output power was so intense the measurement light was weak. This finding reflects the increase in an internal defect and suggests a possibility that light irradiation exerts the influence on long-term cell performance. Moreover, by measuring with feeble light, we found that the changed output recovers by reverse voltage application. The phenomenon of recovery up on comparatively low reverse voltage can be considered as an application for maintaining stability. 相似文献