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91.
广东省大宝山矿业有限公司铜选厂选矿QC小组 《南方金属》1999,(5):42-49
1 小组概况建组时间:1981年7月小组性质:现场管理、攻关型小组活动情况:每月活动一次以上,有记录,有报表循环次数:已完成15个PDCA循环本次循环时间:1997年4月~12月注册编号:1997-05小组成员:见表1表1 铜选厂选矿QC小组情况一览表姓 名文化程度职务、职称组内职务姓 名文化程度职务、职称组内职务钟国健本 科副厂长、工程师组 长庞烈新高 中维修班班长组 员王团生本 科厂长、工程师副组长方长宽高 中维 修 工组 员李辉跃本 科助理工程师副组长张保国高 中值班长、技师组 员龙赞林高 中副厂长、技师组 员吕新才高 … 相似文献
92.
This study was conducted to elucidate the effects of annealing and hydrogenation on the tensile properties of an Fe–0.01 mass% C alloy processed by high-pressure torsion (HPT). By HPT processing, the tensile strength was increased to ∼1500 MPa through grain refinement. Low-temperature annealing further strengthened the HPT-processed specimen because of a simultaneous effect of carbide precipitation and grain refinement. Reduction in the dislocation density and the fraction of low-angle grain boundaries through warm-temperature annealing led to a decrease in hydrogen uptake when the specimens were exposed to high-pressure gaseous hydrogen, and they became less sensitive to hydrogen embrittlement (HE). 相似文献
93.
The synergistic effect of methyltrioctylammonium chloride (QCI) on the extraction of Np(V) by 1-phenyl-3-methyl-4-benzoyl-pyrazolone(HP) in benzene is studied over the pH range 2-6. This system extracts Np(V) better than any previously reported. The interaction of the extractants and monomer-dimer equilibria affect the distribution behavior of Np(V) in a complicated manner. Analysis of the results suggests that NpO2 + (M+) is extracted as mixed dimers, (QMP2QCl)o and (QMP2QP)o. 相似文献
94.
This paper studies the following variant of the Vehicle Routing Problem that we call the Grasp and Delivery for Moving Objects (GDMO) problem, motivated by robot navigation: The input to the problem consists of n products, each of which moves on a predefined path with a fixed constant speed, and a robot arm of capacity one. In each
round, the robot arm grasps one product and then delivers it to the depot. The goal of the problem is to find a collection
of tours such that the robot arm grasps and delivers as many products as possible. In this paper we prove the following results:
(i) If the products move on broken lines with at least one bend, then the GDMO is MAXSNP-hard, and (ii) it can be approximated
with ratio 2. However, (iii) if we impose the “straight line without bend” restriction on the motion of every product, then
the GDMO becomes tractable.
Y. Asahiro’s research was supported in part by Grant-in-Aid for Young Scientists 15700021, and Research on Priority Areas
16092223.
E. Miyano’s research was supported in part by Grant-in-Aid for Research on Priority Areas 16092223.
Presently, S. Shimoirisa is with the Software Development Engineering Department, Products Development Center, Retail Information
Systems Company, Toshiba TEC Corporation. 相似文献
95.
To develop a quantitative method for predicting shrinkage porosity in squeeze casting 总被引:1,自引:0,他引:1
In order to secure high strength and high elongation of suspension parts, it is critical to predict shrinkage porosity quantitatively. A new simulation method for quantitative predic'don of shrinkage porosity when replenishing molten metal has been proposed for squeeze casting process. To examine the accuracy of the calculation model, the proposed method was applied to a plate model. 相似文献
96.
Hiromi Yamashita Yo Fujii Yuichi Ichihashi Shu Gou Zhang Keita Ikeue Dal Ryung Park Keiko Koyano Takashi Tatsumi Masakazu Anpo 《Catalysis Today》1998,45(1-4):221-227
Highly dispersed titanium oxide catalysts have been prepared within zeolite cavities as well as in the zeolite framework and utilized as photocatalysts for the reduction of CO2 with H2O to produce CH4 and CH3OH at 328 K. In situ photoluminescence, ESR, diffuse reflectance absorption and XAFS investigations indicate that the titanium oxide species are highly dispersed within the zeolite cavities and framework and exist in tetrahedral coordination. The charge transfer excited state of the highly dispersed titanium oxide species play a significant role in the reduction of CO2 with H2O with a high selectivity for the formation of CH3OH, while the catalysts involving the aggregated octahedrally coordinated titanium oxide species show a high selectivity to produce CH4, being similar to reactions on the powdered TiO2 catalysts. Ti-mesoporous molecular sieves exhibit high photocatalytic reactivity for the formation of CH3OH, its reactivity being much higher than the powdered TiO2 catalysts. The addition of Pt onto the highly dispersed titanium oxide catalysts promotes the charge separation which leads to an increase in the formation of CH4 in place of CH3OH formation. 相似文献
97.
Atsushi Satsuma Hironaka Kanbe Kannan Srinivasan Shin-ich Komai Yuichi Kamiya Tadashi Hattori 《Microporous and mesoporous materials》2008,110(2-3):528-533
Nano-sized interlayer space of lamellar vanadyl benzylphosphate was controlled by water content in starting solution. Depending on the water content, three types of lamellar vanadyl benzylphosphate having basal spacings of 1.4 nm, 1.9 nm and 2.3 nm were obtained. It was suggested that the difference in the concentrations of benzyl and hydroxyl groups in the interlayer leads to the variation of the interlayer space. 相似文献
98.
Serap Pulatsü Akasya Topçu Mine Krkaaç Gülten Köksal 《Lakes & Reservoirs: Research and Management》2008,13(3):197-205
This study examined the vertical distributions of total phosphorus (TP) and phosphorus fractions, and the iron and organic matter, in the littoral sediment in a macrophyte‐dominated, clearwater state in Lake Mogan between September 2005 and August 2006. Benthic macroinvertebrates and total bacteria in the sediment also were determined. No clear seasonal or depth‐related (0–20 cm) patterns were found in sediment concentrations for the measured parameters. The phosphorus release was quantitatively very low, and a negative phosphorus release (–0.132 µg m?2 day?1) was measured during the summer months. The TP concentrations of the sediment samples ranged between 675.00 and 1463.80 µg g?1 dry weight (DW), and the trophic level of the lake was eutrophic. On average, inorganic phosphorus fractions comprised the largest fraction (63%), while organic‐bound phosphorus (Org ≈ P) constituted 37% of the TP in Lake Mogan. The most important phosphorus‐immobilizing factors are high iron content (14 200–47 750 µg g?1 DW), the sediment's clay content (47.80–51.80%), and an abundance of macrophytes at the sampling station. The low abundance of benthic macroinvertebrates (510–850 individuals m?2), which depend on sediments with high iron and low organic matter (5.42–13.30%), played a role in the sediment phosphorus retention. Although bacterial abundance in the surficial sediment appeared to be positively correlated to temperature, the overlying water did not experience anoxic conditions, supporting a state in which bacteria were able to retain phosphorus in their cell structures. Long‐term changes in the sediments of Lake Mogan must be monitored lake. In order to optimize the management of the lake, and to determine the longevity of a clearwater state following management measures and continued external phosphorus loading, long‐term changes in the sediments of Lake Morgan must be monitored. 相似文献
99.
Ishii T. Osabe T. Mine T. Sano T. Atwood B. Yano K. 《Electron Devices, IEEE Transactions on》2004,51(11):1805-1810
This work presents a gain-cell solution in which a novel ultrathin polysilicon film transistor provides the basis for dense and low-power embedded random-access memory (RAM). This is made possible by the new transistor's 2-nm-thick channel, which realizes a quantum-confinement effect that produces a low leakage current value of only 10/sup -19/ A at room temperature. The memory has the potential to solve the power and stability problems that static RAM (SRAM) is going to face in the very near future. 相似文献
100.
Yosuke Higo Fusao Oka Sayuri Kimoto Yuichi Morinaka Yusuke Goto Zhen Chen 《Soils and Foundations》2010,50(4):515-532
The Material Point Method (MPM), as proposed by Sulsky et al. (1994), has been developed to simulate large deformations and failure evolution involving different material phases in a single computational domain. A continuum body is divided into a finite number of subregions represented by Lagrangian material points, while the governing equations are formulated and solved with the Eulerian grid. Since this grid can be chosen arbitrarily, mesh tangling does not appear in the MPM. To design a simple but robust spatial discretization procedure, the MPM is coupled with the finite difference method (FDM) in the present study for simulating fully and partially saturated elasto-plastic soil responses based on the simplified three-phase method. Governing equations for the soil skeleton and the pore fluid are discretized by the MPM and FDM, respectively. Soil-water coupled analyses for fully saturated soils and seepage-deformation coupled analyses for unsaturated soils are performed, and the potential of the proposed method is demonstrated via numerical examples. 相似文献