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131.
BACKGROUND: So far, in research studies, the age of cows has not been considered as a factor that may influence the changes in the content of milk ingredients with antioxidant properties modified by the feed supplementation. The aim of this study was to determine the influence of supplementation on the content of ingredients having antioxidant properties and to determine the influence of the age of cows taking part in the experiment on these changes. The experiment was conducted using 20 Polish Holstein Friesian cows, 10 primiparous and 10 multiparous. The combined supplementation of fish oil and linseed constituted the experimental factor. RESULTS: The milk of primiparous cows after 21 days of supplementation was characterised by a higher content of C18:1 trans ‐11, C18:2 cis ‐9, trans ‐11, α‐retinol, α‐tocopherol and β‐lactoglobulin compared to the milk of multiparous cows, in which a higher level of lactoferrin, C20:5 and β‐carotene was recorded. In both groups an increase in the total antioxidant status was noted (a higher level in the milk of primiparous cows). CONCLUSIONS: Modification of the diet of cows with fish oil and linseed significantly influenced antioxidant properties of their milk; however, the response of multiparous and primaparous cows was noticeably different to the supplement introduced. Copyright © 2012 Society of Chemical Industry  相似文献   
132.
Many researchers are increasingly interested in human exposure to house dust containing household compounds such as polybrominated diphenylethers (PBDEs). Nevertheless, no investigations have addressed the endocrine-disrupting potencies of compounds contained in indoor dust. This study specifically addresses endocrine-disrupting potencies such as dioxin-like activity and human transthyretin (TTR)-binding potencies. Using in vitro bioassays, we investigated these activity levels in indoor dusts. We performed exposure assessments of active compounds that are contained in house dust for subsequent evaluation of house dusts' risks to humans. Dioxin-like and TTR-binding activities in sulfuric acid treatment extracts of house and office dust were investigated using Dioxin-Responsive Chemical-Activated LUciferase gene eXpression assay (DR-CALUX) and TTR-binding assay (in vitro competitive human TTR-binding assay). Dioxin-like activities in indoor dust were 38-1400 pg CALUX-TEQ (2,3,7,8-TCDD equivalent)/g (median 160 pg CALUX-TEQ/g) and TTR-binding potencies were 300-5000 pmol T4EQ (thyroxine (T4) equivalent)/g (median 1000 pmol T4EQ/g), which are higher values than those in other environmental samples, e.g., contaminated sediments. These exposure results suggest that children might be affected by both dioxin-like compounds and TTR-binding compounds via house dust. When the ingestion rate, CALUX-TEQ, and T4EQ for house dust are high, thyroid hormone homeostasis in children may be disrupted.  相似文献   
133.
The optimization of parameters of synthesis of belite cement clinker from coal fly ash of high Ca content is presented in this paper. The synthesis process is based on the hydrothermal-calcination-route of the fly ash without extra additions. The hydrothermal treatment was carried out in demineralized water and a 1 M NaOH solution for 4 h at the temperatures of 100 degrees C, 150 degrees C, and 200 degrees C. The precursors obtained during the hydrothermal treatmentwere heated at temperatures of 700 degrees C, 800 degrees C, 900 degrees C, and 1000 degrees C. The changes of fly ash composition after the different treatments were characterized by X-ray diffraction (XRD), FT infrared (FTIR) spectroscopy, surface area (BET-N2), and thermal analyses. From the results obtained we concluded that the optimum temperature of the hydrothermal treatment was 200 degrees C, and the optimum temperature for obtaining the belite cement clinker was 800 degrees C.  相似文献   
134.
In the present work, we report our work concerning the synthesis of heteropolymers of poly(?-caprolactone)-polyoxomolybdate-poly(?-caprolactone) using ring-opening polymerization (ROP) of ?-caprolactone monomer initiated by two hydroxyl groups attached on the two sides of a polyoxomolybdate cluster which was organically modified using pentaerythritols. Since the hydroxyl groups on polyoxomolybdate macroinitiator are less reactive, ring-opening polymerization were finally carried out by using 4,4′-(dimethylamino) pyridine to activate ?-caprolactone monomer. The polyoxomolybdate-containing heteropolymers were confirmed in detail by 1H NMR, FT-IR, GPC, TGA and XPS methods. Although the size of polyoxomolybdate cluster is extremely small compared to PCL chains, it was also found that POM played an important role in crystallization process. Self-assembly of such heteropolymers in mixed solvents were investigated and the analysis of formed spherical aggregates with multiple concaves on the surface was supported by TEM results and 3D electron tomography.  相似文献   
135.
Thin TiO2 layers grown at 130°C on SiO2-coated Si substrates by atomic layer deposition (ALD) using TTIP and H2O as precursors were annealed, and the effects of the annealing temperature on the resulting electrical properties of TiO2 and the interface properties between a Pt electrode and TiO2 were examined using transmission line model (TLM) structures. The as-deposited TiO2 thin film had an amorphous structure with OH groups and a high resistivity of 6×103Ω-cm. Vacuum annealing at 700 °C transformed the amorphous film into an anatase structure and reduced its resistivity to 0.04Ω-cm. In addition, the vacuum-annealing of the TiO2/SiO2 structure at 700°C produced free silicon at the TiO2-SiO2 interface as a result of the reaction between the Ti interstitials and SiO2. The SiO2 formed on the TiO2 surface caused a Schottky contact, which was characterized by the TLM method. The use of the TLM method enabled the accurate measurement of the resistivity of the vacuum-annealed TiO2 films and the characterization of the Schottky contacts of the metal electrode to the TiO2.  相似文献   
136.
LaC2@CNC/LaB6 nanocomposites were prepared using a spark plasma sintering system, and their mechanical properties and the intensity of characteristic La X-rays from the composites were characterized for application as X-ray target material. Using LaB6 as a binder, we succeeded in producing LaC2@CNC/LaB6 nanocomposites with a bulk density (2.91 g/cm3) and specific electric resistance (3.12 × 10− 4 Ω cm) through solidification at 2123 K. The fracture bending strength of LaC2@CNC/LaB6 nanocomposites (224 MPa) was 1.5 times larger than that observed for graphite/LaB6 composites. The most emitted characteristic La Lα X-ray from LaC2@CNC/LaB6 nanocomposites was 7743 counts/mm2/s in comparison with 6372 counts/mm2/s for graphite/LaB6 composites.  相似文献   
137.
Abstract

A simplified explicit formula for the displacement bounds of the beam‐column subjected to time‐dependent boundary constraints is proposed. The formula is derived by means of removing time dependence from the boundary conditions. The proposed bounds provide a quick estimation of the displacements for problems with complex loading conditions.  相似文献   
138.
Thermoelastic characteristics of thermal barrier coatings (TBCs) with vertical cracks were analyzed through mathematical approaches to investigate the thermoelastic behaviors of TBCs in a service temperature. TriplexPro?-200 system was applied to prepare the relatively dense TBC using METECO 204NS powder. The microstructure of top coat in the TBC was just controlled to create vertical type cracks by reheating without powder feeding in same equipment and rapid cooling process. A couple of governing partial differential equations were derived based on the thermoelastic theory, and a finite volume model was developed to the governing equations to evaluate the thermoelastic characteristics, such as temperature distribution profile, displacement, and stress, inducing a thermal fatigue. For the specimen with two or more vertical type cracks, smaller displacement appears to longitudinal direction and larger displacement to radial direction as the number of crack increases. In the longitudinal stress distribution profiles to z-direction, the tensile stress at the interface between the bond coat and the substrate converts into the compressive stress when the specimen has vertical cracks more than two, while larger magnitude undulation develops for the specimen with smaller number of crack in the radial stress distribution profiles. The results obtained demonstrate that multiple vertical cracks enhance the thermal durability and extend the lifetime of TBCs.  相似文献   
139.
This paper describes a methodology for developing and verifying a class of distributed systems in which the state space may be discrete or continuous. Our focus is on systems where changes are local in that a small number of components change state while the remainder of the system is unchanged. A proof methodology is developed that ensures global properties, such as invariants and convergence, by guaranteeing local properties within subsystems. This methodology is used to prove the correctness of concrete examples. We present a PVS library of theorems and proofs that can be used to reduce the work required to develop and verify programs in this class. A transformation of these libraries to Java is also outlined.  相似文献   
140.
The paper included the most current information about the mechanisms of ototoxicity of five groups of the most popular drugs: a) antibiotics, b) chemotherapeutics (cytostatic) agents, c) loop diuretics, d) salicylate and nonsteroidal anti-inflammatory drugs, as well as e) progestagen contraceptives minimized or even prevented by thoughtful selection of drug, attention to risk factors and careful patient monitoring.  相似文献   
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