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101.
102.
Isolation and characterization of protein fractions from deoiled rice bran   总被引:5,自引:0,他引:5  
Rice bran contains underutilised protein materials. Sequential extraction of rice bran protein (RBP) from defatted rice bran was conducted based on the differences in their solubility. Three extraction methods were investigated. Method 1 involved the isoelectric and acetone precipitation using water, 50 g kg−1 NaCl, 0.02 mol L−1 NaOH and 70% ethanol as extracting solvents for albumin (pH 4.1), globulin (pH 4.3), glutelin (pH 4.8) and prolamin, respectively. Method 2 adopted dialysis and sequential extraction was carried out with 20 g kg−1 NaCl, 70% ethanol, 0.1 mol L−1 acetic acid and 0.1 mol L−1 NaOH solution as extracting solvents. Method 3 combined dialysis, isoelectric and acetone precipitation for the extraction. Based on the yields and data obtained from sodium dodecyl sulphate polyacrylamide gel electrophoresis, size-exclusion chromatography and differential scanning calorimetry, method 3 was chosen for the isolation and characterization of RBPs. Rice bran protein fraction (RBPF)—albumin, globulin, glutelin and prolamin were obtained in good yields. Denaturation temperature and enthalpy values of denaturation of RBPF vary. Highest phytate content was found in albumin and lowest in prolamin. The highest antioxidative and hemagglutinating activities were observed in albumin.  相似文献   
103.
Soil microorganisms play an important role in maintaining soil pH at levels suitable for other soil organisms. To clarify the biological neutralization mechanism in soil, we isolated soil microorganisms showing a high ability to neutralize acids and studied their characteristics. From our taxonomic study, three isolated strains were identified as filamentous fungi, namely Mucor sp., Aspergillus fumigatus, and Aureobasidium pullulans. These strains could secrete basic materials, such as ammonia, for neutralization, grow in the medium at pH 4.0 and increase the pH of the medium to approximately 8.0. These microbial cells could neutralize not only nitric acid but also sulfuric and hydrochloric acids. The strains could also grow by utilizing nitric acid as a sole nitrogen source. In the soil containing these organisms, the pH was maintained in the neutral range by the buffering action of basic materials that they secrete. These results suggest that these fungal cells are useful for protecting the soil from acidification by acid rain.  相似文献   
104.
This work demonstrated the first-ever cold-start operation of an ammonia (NH3)-fueled four-cylinder spark ignition engine with an on-board fuel reformer, applying autothermal reforming. In this system, an electrically heated NH3-air mixture was provided to a reforming catalyst and approximately 3 s was found to elapse between the start of engine rotation and the onset of combustion. Stable fast idle operation in conjunction with a cold start was realized with a H2-to-NH3 molar ratio of 2:1. Nearly zero NH3 emissions were achieved during cold start and fast idle until the engine warmed up, by adsorbing unburned NH3 passing through a three-way catalyst before the catalyst was sufficiently warmed up. The NH3 adsorption capacity of this system could be regenerated during the engine warm-up when the engine was running under lean conditions.  相似文献   
105.
3,5-Dihydroxy-4-methoxybenzyl alcohol (DHMBA), an antioxidant isolated from the Pacific oyster (Crassostrea gigas), was studied in a cell-based fluorometric antioxidant assay using human hepatocyte-derived cells (C3A) and diphenyl-1-pyrenylphosphine (DPPP) as a fluorescent probe. In comparison with two hydrophilic antioxidants, DHMBA showed the stronger inhibition of DPPP-mediated fluorescence than chlorogenic acid and l-ascorbic acid: at a concentration of 320 μM of DPPP, the inhibition was 26.4 ± 2.6%, 11.1 ± 1.2%, and 0 ± 2.0% for DHMBA, chlorogenic acid, and l-ascorbic acid, respectively (mean ± SD, n = 4). Their relative oxygen radical absorbance capacities (ORAC) were dissociated with their cell-based antioxidant activities: 1.47 ± 0.40, 4.57 ± 0.30, and 0.53 ± 0.13 μmol TE/μmol for DHMBA, chlorogenic acid, and l-ascorbic acid, respectively (mean ± SD, n = 4). The amphiphilicity of DHMBA was better than chlorogenic acid and l-ascorbic acid might underlie this dissociation. Since the C3A cells are human hepatoma-derived cells, DHMBA might be useful in the prevention and treatment of liver diseases by involving an oxidation process.  相似文献   
106.
In recently advanced rapid prototyping and manufacturing methods, one additional process is to use an electron beam to fabricate metal objects by the layer by layer sintering and/or melting metal powder. This method is often called electron beam melting (EBM). This study examined the mechanical properties, the grindability and corrosion resistance of Ti-6Al-4V ELI (extra low interstitial) specimens which were fabricated by the electron beam melting (EBM) process. Dumbbell-shaped specimens and two kinds of plate specimens were prepared using the Ti-6Al-4V ELI powder in the EBM system. The yield strength, tensile strength, modulus of elasticity and percent elongation at a crosshead speed of 0.25 mm/min were tested. The Vickers hardness in interior structures was determined. Grindability was evaluated as volume loss (mm3) when the specimen was abraded using a SiC wheel at 1250 m/min for 1 min. Lastly, corrosion behavior was examined using the dynamic potentiostatic polarization technique in an artificial saliva at 37 °C. As controls, cast and commercial wrought alloys of Ti-6Al-4V ELI and commercially pure titanium (CP Ti) were evaluated. Cast specimens were prepared in a centrifugal casting machine using a MgO based mold. For the cast specimens, all the mechanical properties, grindability and corrosion characteristics were tested. On the other hand, for wrought specimens, only grindability and corrosion properties were tested. The yield and tensile strength of the as-fabricated Ti-6Al-4V ELI specimens without any additional metallurgical treatments were found to be 735 MPa and 775 MPa, respectively. The elongation was 2.3%. These values are well within many of precious and non-precious dental casting alloys.  相似文献   
107.
The microstructures and mechanical properties of amorphous/nanocrystalline hybrid TiNi wires produced by severe cold drawing were investigated. Annealed wires of Ti-50.9?mol%Ni and Ti-41?mol%Ni-8.5?mol%Cu were subjected to severe cold drawing of 50-70% reduction. The as-drawn TiNi wires were composed of the mixture of amorphous phase and predominantly B2 nanocrystalline phase. Young??s modulus increased with the drawing reduction which can be attributed to the increase in the amount of amorphous phase. For the binary TiNi wires, the volume fraction of amorphous phase was estimated to be about 60% from Young??s modulus and electrical resistivity. The wires drawn over 60% exhibited peculiar large linear elastic strain which is quite different from superelasticity. Aging at 573?K led to an increase in tensile elongation as well as in the recoverable strain. The amorphization by cold drawing was also confirmed for Ti-41?mol%Ni-8.5?mol%Cu in 62% drawn wires.  相似文献   
108.
Conventional ultrasonic displacement-measuring systems normally employ the pulse-echo technique. Resultant resolution capability, however, typically is not suitable for meeting high-dimensional, in-process measurement standards used in cutting and grinding operations. This paper presents a new ultrasonic sensor for displacement measurement based on astigmatic focus error detection. The measuring principle and basic analysis applied in the design method are described in detail, after which the validity of the principle is demonstrated by the results of experimental evaluations.  相似文献   
109.
The design and production of Ti-6Al-4V ELI customized dental implants   总被引:1,自引:0,他引:1  
This paper addresses the production of customized Ti-6Al-4V ELI dental implants via electron beam melting (EBM). The melting of Ti-6Al-4V ELI powder produces implants with great biocompatibility, fi ne mechanical performance, and a high bone ingrowth potential. The EBM technology is used to produce one-component dental implants that mimic the exact shape of the patient’s tooth, replacing the traditional, three-component, “screw-like” standardized dental implants currently used. The new generation of implants provides the possibility of simplifying pre-insertion procedures leading to faster healing time, and the potential of better and stronger osseointegration, specifi cally through incorporating lattice structure design.  相似文献   
110.
A case of acute undifferentiated leukemia (AUL), accompanied by subcutaneous tumor and thymoma is reported. The analysis of immunophenotype showed that the leukemic blasts were positive for CD7, HLA-DR, CD38 and CD34 in 17.5% but negative results were obtained for other lymphoid and myeloid antigens. The leukemic blasts had a rearranged immunoglobulin heavy chain (IgH) gene and T cell receptor delta (TCR-delta) chain gene chromosomal abnormality, 47, XY, +8, t(13; 17) (q12; q21), -17, +M was observed. In general, the CR rate is low and prognosis is poor in patients with AUL. In our case, CR was not achieved by the therapy with JALSG-ALL87 protocol, but was achieved by subsequent treatment with high dose ara-C therapy and combination chemotherapy including intermediate-dose ara-C, mitoxantrone, etoposide and prednisolone.  相似文献   
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