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11.
Methodical aspects relating to determination of serum-bactericidal capacities were studied, with the view to using them to test the bearing of abiotic environmental factors on defence mechanisms against infections. Communicated are methodical experience by which to enhance the methods used to higher accuracy as well as experience regarding biological variance in calf and results obtained from follow-up checks in which antigens were systematically used. Reference is made also to other methodical issues. The method actually used to determine serum-bactericidal capacity was found to be suitable for an assessment of reactivity of infection defence in calf for its good accuracy. Follow-up checks, using antigens, will enable better assessment of the action of abiotic environmental factors on the complex defence system of calf.  相似文献   
12.
We studied theoretically the phase-sensitive c-axis Bi2Sr2CaCu2O8+δ (BSCCO) bicrystal twist Josephson junction experiments of Li et al. (Phys. Rev. Lett. 83, 4160 (1999)), calculating the critical current as a function of the twist angle in a wide variety of models. The data provide strong evidence that the c-axis tunneling in BSCCO is incoherent, and that the order parameter is s-wave for TT c.  相似文献   
13.
Atmospheric haloacetates can arise from photochemical degradation of halogenated hydrocarbons and from direct anthropogenic emissions. Furthermore, there is also evidence of natural sources although these are quantitatively uncertain. As haloacetates are highly soluble in water, hydrometeors are most significant for their deposition. Fogwater (96 samples) and rainwater samples (over 100 samples) were collected from July 1998 to March 1999 at an ecological research site in northeastern Bavaria, Germany. They were analyzed for monofluoroacetate (MFA), difluoroacetate (DFA), trifluoroacetate (TFA), monochloroacetate (MCA), dichloroacetate (DCA), trichloroacetate (TCA), monobromoacetate (MBA), and dibromoacetate (DBA). The major inorganic ions were also determined. High concentrations of up to 11 microg/L MCA, 5 microg/L DCA, 2 microg/L TCA, and 2 microg/L TFA were found in fogwater associated with westerly winds. Backward trajectories were calculated to determine the origin of the air masses. MBA and DBA have highest concentrations in fogwater advected with air originating from the Atlantic, suggesting the marine origin of these two compounds. All analyzed substances show higher average concentrations in fog than in rain. Estimates of the deposition of haloacetates suggest that the contribution of fog may be more important than rain for the total burden of a forest ecosystem.  相似文献   
14.
An Al96.1–Cu3.9 to Al51.4–Cu48.6 material library was obtained by thermal co-deposition and characterized by EDX and XRD. The crystallographic data reveals the presence of Al2Cu and pure aluminium depending on the film composition and following the stoichiometry. Utilizing a scanning droplet cell setup, the zero current potential for anodization, the oxide formation factor and the dielectric constant of the oxide formed are presented with high resolution along the composition gradient.While the dielectric constant of the oxide formed remains nearly unaffected by the increasing copper content of the base material along the composition gradient, the zero current potential shows well defined steps between 6.9 and 8.5 at.% as well as between 20.9 and 26.7 at.% copper indicating an increased thickness of the native oxide present on the film. Additionally, starting around 25 at.% copper, oxygen evolution gradually superimposes the oxide growth and in turn significantly reduces the current efficiency for anodization. The formation of the intermetallic phase Al2Cu was linked to both phenomena as it promotes the growth of native oxides and current leakage by oxygen evolution.  相似文献   
15.
This paper describes problems with the provision of guidelines for the user at machines today. For the situation-oriented provision of information, a concept stemadi will be developed. In the middle of the concept is the stemadi information model for the technical documentation that is based on the structure of the machine and is automatically available for use. Besides the physical and functional aspects, the model also describes the guidelines for the user at the machine. The extended and modified structure of the technical documentation realized in the stemadi information model allows the automated adaptation of the guidelines to the existent publication medium and the provision of the guidelines on this medium. The differences between the publication media (resolution, size, colour depth, etc.) will be considered here. With the situation-oriented and publication medium oriented extraction of the relevant guidelines according to the information model, the user at the machine will be supported in making decisions.  相似文献   
16.
17.
The complex dielectric constant of O-acetyl-starches with regioselective and the statistical distribution of substituents at the anhydroglucose unit (AGU) are measured in an extended frequency range from 10 mHz to 2 MHz and in the low temperature range from −120 to 0°C. The experimentally determined relaxation spectra are evaluated with the well-known model function of Havriliak–Negami for relaxation processes. In the case of 2-O-acetyl-starch two significant relaxations are detected which are associated with the orientational motion of the methylolgroup at the AGU and the acetylgroup in position C-2. The activation energies are 48 and 60 kJ/mol, respectively. Owing to that assignment of relaxations at the AGU with acetylation in position C-2 has proved that it is possible to describe further relaxation processes in acetylated amylomaize starch with a statistical substitution pattern. It was found that an additional relaxation process is associated with the dynamics of the acetylgroup at the position C-6 at the AGU and characterized by a lower activation energy of 28 kJ/mol.

From the analytical point of view these results of dielectric spectroscopy analysis demonstrate that the mobility of the side groups depend significantly on the position at the AGU and the type of substituent in their frequency and temperature dependence.  相似文献   

18.
Design and Characterization of Purely Textile Patch Antennas   总被引:1,自引:0,他引:1  
In this paper, we present four purely textile patch antennas for Bluetooth applications in wearable computing using the frequency range around 2.4 GHz. The textile materials and the planar antenna shape provide a smooth integration into clothing while preserving the typical properties of textiles. The four antennas differ in the deployed materials and in the antenna polarization, but all of them feature a microstrip line as antenna feed. We have developed a manufacturing process that guarantees unaffected electrical behavior of the individual materials when composed to an antenna. Thus, the conductive textiles possess a sheet resistance of less than 1Omega/squarein order to keep losses at a minimum. The process also satisfies our requirements in terms of accuracy meeting the Bluetooth specifications. Our investigations not only characterize the performance of the antennas in planar shape, but also under defined bending conditions that resemble those of a worn garment. We show that the antennas can withstand clothing bends down to a radius of 37.5 mm without violating specifications  相似文献   
19.
Combination of X-ray diffraction (XRD) and scanning electron microscopy (SEM) was used for investigation of local composition gradients in the hard-phases of cermets. XRD revealed distribution of lattice parameters in hard-phase grains, from which the composition gradients in the hard-phases were estimated using an appropriate microstructure model. This microstructure model was build with the aid of SEM micrographs, which were taken with back-scattered electrons (BSE) and completed by the registration of the electron back-scatter diffraction (EBSD) patterns and characteristic X-ray spectra. SEM/BSE yielded the first information about the spatial distribution of elements in individual hard-phase grains, SEM/EBSD about the morphology, the size and the size distribution of these grains. The final interpretation of the distribution of lattice parameters, which was obtained from the X-ray line profile analysis, was done with the aid of the local elemental analysis that was performed using SEM with the energy dispersive analysis of the characteristic X-ray spectra (EDX) and the known dependence of the lattice parameters on concentration.  相似文献   
20.
Summary We investigated the synthesis of polymer-bound iodonium salts with chloride as anion by polymer analogous reaction. The structure of polymers was determined with NMR-spectroscopy, MS-analysis as well as by model substances. The polymers give transparent films on glass, they decomposed during irradiation and eliminated HCl. The HCl-elimination in the films can be detected with indicators and also with potentiometric titration with AgNO3.  相似文献   
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