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701.
For improving the ozone consumption efficiency (OCE) of the ozone-electrolysis process, an ozone-electrolysis system with an independent electrolytic cell from an ozone contactor (indirect ozone injection system) and a three-dimensional electrode were introduced in this study. The reactor successfully enhanced the OCE and the ratio of 1,4-dioxane degradation rate to ozone injection rate (RDO) in comparison with the previous reactor. The three-dimensional electrode also contributed the improvement of the OCE and the RDO due to lowering the current density on the cathode. As the indirect ozone injection system allows higher degree of freedom for the reactor design, it is useful for application of ozone-electrolysis to practical water treatments. 相似文献
702.
Thomas Albrecht Stavros Papadokonstantakis Hirokazu Sugiyama Konrad Hungerbühler 《Chemical Engineering Research and Design》2010,88(5-6):529-550
One of the key challenges for the design of sustainable chemical processes is to incorporate such concepts in the early phases of process design. In recent years, a few frameworks have been published to this direction, focusing mainly on continuous processes. However, the wide use of batch processes for the production of “low volume high value” chemicals makes the extension of such frameworks to this production environment indispensable. In the present study a recently presented multi-stage framework for multi-objective continuous process assessment is modified to incorporate batch process design aspects (e.g., cycle times, equipment utilization) in the form of early design phase indicators. Accordingly, a Productivity Loss Index (PLI) is defined for estimating periodic costs and environmental impacts, economic and environmental indicators are adjusted and a procedure to generate a base case separation process flowsheet is implemented. The modified framework is demonstrated on the design of a production process for 4-(2-methoxyethyl)-phenol considering seven potential synthesis routes. 相似文献
703.
Hirokazu Kikuchi Sho Nakahara Takaaki Tomai Kazuo Terashima 《The Journal of Supercritical Fluids》2010,55(1):325-332
A two-dimensional, sheet-like dielectric barrier discharge microplasma that can be generated in supercritical fluids was developed. With this type of plasma, generated in supercritical xenon, nanocrystalline diamonds and diamondoid-like sp3 bonded nano-hydrocarbons were synthesized by using adamantane as a precursor and seed. Pressure and temperature were set close to the critical point of xenon at 6.3 MPa and 290.2 K, respectively. The peak-to-peak voltage for microplasma generation was between 3.4 and 7.1 kV, at a frequency of 10 kHz and the power consumption of the microplasma determined from the I-V measurements reached about 30 mW. Transmission electron microscopy analysis of the lattice of the synthesized particles revealed crystal structures similar to those observed in nanodiamonds, while micro-Raman spectra yielded features also found in Raman and ab initio computational studies of diamondoids. 相似文献
704.
Tomoya Fujie Masaki Murakami Eiko Yoshida Shuji Yasuike Tomoki Kimura Yasuyuki Fujiwara Chika Yamamoto Toshiyuki Kaji 《International journal of molecular sciences》2016,17(9)
Vascular endothelial cells cover the luminal surface of blood vessels and contribute to the prevention of vascular disorders such as atherosclerosis. Metallothionein (MT) is a low molecular weight, cysteine-rich, metal-binding, inducible protein, which protects cells from the toxicity of heavy metals and active oxygen species. Endothelial MT is not induced by inorganic zinc. Adequate tools are required to investigate the mechanisms underlying endothelial MT induction. In the present study, we found that an organoantimony compound, tris(pentafluorophenyl)stibane, induces gene expression of MT-1A and MT-2A, which are subisoforms of MT in bovine aortic endothelial cells. The data reveal that MT-1A is induced by activation of both the MTF-1–MRE and Nrf2–ARE pathways, whereas MT-2A expression requires only activation of the MTF-1–MRE pathway. The present data suggest that the original role of MT-1 is to protect cells from heavy metal toxicity and oxidative stress in the biological defense system, while that of MT-2 is to regulate intracellular zinc metabolism. 相似文献
705.
Akiko Isa Jun Minamino Haruna Mizuno Shigehiko Suzuki Yoichi Kojima Hirokazu Ito 《木材化学与工艺学杂志》2013,33(3):208-216
Abstract To improve the water resistance of bamboo flour/high-density polyethylene (HDPE) composites, the effects of plastic content, coupling agents, and the addition of micro-fibrillated cellulose (MFC) on formulations were studied, and their rheological and mechanical properties were evaluated. The composites were prepared by injecting molding with a basic composition of equivalent amounts of bamboo flour and HDPE, and the melting fluidity of the compounds, tensile strength, and tensile modulus of the composites were determined. An increase in water resistance was detected in all three tests. By increasing the plastic content, negative effects such as a decreased tensile modulus were observed. When evaluating the compatibility between bamboo flour and plastic using coupling agents and MFC addition, positive effects were noted for water resistance, melting fluidity, and tensile modulus. We also confirmed that the procedure used to increase the compatibility between bamboo flour and plastic could easily be used for industrial applications by changing the coupling agents. Overall, a novel positive property (increased tensile modulus) and an increased water resistance were observed after MFC addition. 相似文献
706.
One of the strengthening methods of composite connection is the employment of reinforcing elements in the adhesive layer. Using of additional elements in the adhesive layer make uniform stress distribution and improves the strength and toughness of the connection. In this paper, metal wires were used to reinforce the adhesive joints of composites. The effects of the number of wires, wire diameter, wire stiffness, angle of wire and the adhesive type on the strength of the adhesive reinforced bonded composite joints were investigated experimentally and numerically. A finite element model was developed to study the stress distribution in the reinforced adhesive joints. The numerical results showed a good agreement with the experimental observation. It was found that increasing the number of wires and wire diameter, choosing a stiffer material for the wire and increasing the wire angle, uniform the stress distribution and reduced the maximum and average stress values in the adhesive layer. For the appropriate reinforcing wire parameters, the joint strength increased more than 90% in this study. It also observed that the using metal wires as a reinforcing element was more effective in the ductile adhesion than the brittle ones. 相似文献
707.
Hirokazu Yamada Hiroshi Kawamura George Kalinin Fumiki Takada 《Journal of Nuclear Materials》2005,340(1):57-63
The objective of this study is to make clear the effect of neutron irradiation on mechanical properties of laser weldments using irradiated material. This estimation is necessary for the application to joining coolant piping of the ITER blanket. Irradiation testing was performed at Japan Material Testing Reactor (JMTR). On the irradiation condition for weldments using irradiated material, fast neutron fluence was 1.4 × 1024 n/m2, which corresponds to a displacement damage rate of 0.26 displacement per atom (dpa) and irradiation temperature 200 °C. The results of this study show that tensile properties of all weldments changed into that of base material by the effect of neutron irradiation. The results of hardness tests show that irradiation hardening at an irradiation damage dose of 0.3 dpa is almost same as that at irradiation damage 0.6 dpa. It is concluded that irradiated weldments using irradiated material were moved toward irradiated base material on tensile and hardness properties up to 0.6 dpa. On the other hand, tensile properties of base material were changed by the effect of neutron irradiation up to about 0.3 dpa, and with much less change from 0.3 dpa to 0.6 dpa. It is inferred that the effect of neutron irradiation of SS316LN-IG almost saturated up to 0.3 dpa. 相似文献
708.
Structural changes during the creep process of ultrahigh‐strength polyethylene fiber (UHSPE) were investigated using X‐ray and the solid‐state NMR techniques. As the creep strain increases, the quantity of the amorphous phase area estimated by the 13C‐NMR method increases until the final creep rupture. On the other hand, the amorphous quantity estimated by the X‐ray method does not change noticeably. To explain this contrast, we proposed a new model that illustrates how the defects such as chain ends incorporated into the crystalline phase are excluded from the crystallite and agglomerate to generate a new amorphous area, which has a size hardly detected by the X‐ray method. These small amorphous areas are considered to cause a decrease in the tensile strength and the successive final creep rupture. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 312–320, 2001 相似文献
709.
Nishina T Wada M Ozawa H Hara-Kudo Y Konuma H Hasegawa J Kumagai S 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(1):35-37
The growth responses of Vibrio parahamolyticus to pH, NaCl concentration and temperature changes were studied using serotype O3:K6 and other strains. Growth curves were obtained for 27 different sets of conditions, comprised of three levels of NaCl concentration, pH and temperature. The temperature, pH and NaCl concentrations most favorable for growth were in the order of 25 degrees C, 20 degrees C and 15 degrees C, pH 8, 7 and 5.8, and 1%, 3% and 7%, respectively. The bacteria grew most rapidly at 25 degrees C, at a pH of 7 or 8 in the presence of 1% or 3% NaCl, with the population (initial, ca. 2.5 log CFU/mL) reaching a level log 7 CFU/mL at 12 h. A growth predictive model using the Gompertz equation was generated from the experimental data for any combination of NaCl concentration, pH and temperature within the range used in this study. 相似文献
710.
Hirokazu Ishitobi Keirei Uruma Masato Takeuchi Junichi Ryu Yukitaka Kato 《Applied Thermal Engineering》2013,50(2):1639-1644
Lithium chloride (LiCl) modified magnesium hydroxide (Mg(OH)2) is a potential new material for chemical heat pumps. However, there is insufficient information concerning its dehydration and hydration behavior. In this study, the dehydration and hydration reactions, corresponding to the heat storage and the heat output operations, respectively, of authentic Mg(OH)2 and LiCl-modified Mg(OH)2 were investigated by thermogravimetric methods and near infrared spectroscopy. The dehydration of authentic Mg(OH)2 proceeded as a one-step reaction. In contrast, the dehydration of LiCl-modified Mg(OH)2 occurred in two steps. The dehydration reaction rates were increased by LiCl modification of the Mg(OH)2 surface, while the activation energy for the first-order dehydration reaction was lowered. The mechanism for the hydration reaction of magnesium oxide (MgO) was different to that for the hydration of LiCl-modified MgO. This difference was explained by the effect of the LiCl on the MgO particle surface. 相似文献