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1.
The flux‐modulating synchronous machine (FMSM) is a new type of multipole SM with nonoverlapping concentrated armature and field windings on the stator. This paper compares the output characteristics of two FMSMs through finite element analysis (FEA) and experiments. In both of the FMSMs, the attachment positions of the armature and field windings are swapped. To determine the reason for the discrepancies in their output characteristics, unsaturated inductances were calculated using a d‐q equivalent circuit. In addition, the calculated results of the inductances were confirmed through a visualization of the leakage fluxes using FEA. The results of the study show that the synchronous inductance can be reduced by attaching the armature winding to the air‐gap side of the stator teeth and that the reduction leads to an increase in output power.  相似文献   
2.
Damage detection of CFRP using fiber Bragg gratings   总被引:1,自引:0,他引:1  
  相似文献   
3.
Kenta Suzuki  Masatoshi Tokita 《Polymer》2005,46(19):8313-8320
We investigated liquid crystallization of liquid crystalline polyester BB-5 during isothermal annealing by digital high-fidelity microscope and light scattering. A liquid crystalline spherical domain having a radius of micrometers appeared by annealing at around 180 °C. The domain grew dendritically in all directions. Neighboring liquid crystalline regions coalesced and then interconnected. The interconnected structure changed to a co-continuous two-phase structure with increasing ordering of the liquid crystalline phase, and the interface between the liquid crystalline phase and the isotropic phase became smoother over time. Liquid crystallization stopped before volume filling the whole space, and the liquid crystalline phase and isotropic phase coexisted. The liquid crystalline region became narrower with an increase in the temperature of the liquid crystallization. Such structural development is different from the liquid-liquid phase separation via spinodal decomposition, and it may be attributed to the segregation of non-liquid crystallizable low molecular weight molecules from the growth front by fractionation of the molecular weight distribution during the liquid crystallization in terms of the instability of the diffusion-controlled interface.  相似文献   
4.
5.
Error-free transmission through 10-km single-mode fiber at 10 Gb/s under -13-dB optical reflections has been demonstrated for the first time using a directly modulated 1.3-/spl mu/m InP-based VCSEL without any optical isolator. The 13-GHz relaxation oscillation frequency and stable polarization suppresses relative intensity noise degradation under optical reflection. Only 1-dB error-free power penalty has been observed with optical reflection set with the worst polarization direction.  相似文献   
6.
A high-performance liquid chromatographic method was developed for the determination of a new podophyllotoxin derivative, TOP-53 (I), and TOP-53 glucuronide (II) as its major metabolite in rat plasma and urine. For the analysis of I, the sample was chromatographed on a reversed-phase C18 column with electrochemical detection after consecutive two-step liquid-liquid extractions. Compound II was determined as I after enzymatic hydrolysis of II. This method was validated sufficiently with respect to specificity, accuracy, and precision. The limits of quantitation for both I and II were 2 ng/ml in plasma and 10 ng/ml in urine. The method is thus useful for the pharmacokinetic study of I.  相似文献   
7.
This report describes a case in which a 68-year-old male underwent two operations simultaneously for left coronary ostial stenosis and gastric cancer. Successfully performed procedures were a single coronary artery grafting with the saphenous vein to the left anterior descending artery, and a subtotal gastrectomy using the Billroth II method. The postoperative course was uneventful and the patient was discharged from the hospital in good condition after 42 days. At present, one-year postoperative, the patient has been visiting the outpatient clinic in healthy condition.  相似文献   
8.
9.
We describe an experimental realization of ultra-long-haul (ULH) networks with dynamically reconfigurable transparent optical add-drop multiplexers (OADMs) and optical cross-connects (OXCs). A simple new approach to dispersion management in ULH dense-wavelength-division-multiplexing (DWDM) transparent optical networks is proposed and implemented, which enables excellent transmission performance while avoiding dispersion compensation on a connection-by-connection basis. We demonstrate "broadcast-and-select" node architectures that take full advantage of this method. Our implementation of signal leveling ensures minimum variations of path-averaged power among the wavelength-division-multiplexing (WDM) channels between the dynamic gain-equalizing nodes and results in uniform nonlinear and spontaneous-emission penalties across the WDM spectrum. We achieve 80/spl times/10.7-Gb/s DWDM networking over 4160 km (52 spans/spl times/80 km each) of all-Raman-amplified symmetric dispersion-managed fiber and 13 concatenated OADMs or 320/spl times/320 wavelength-port OXCs with 320-km node spacing. The WDM channels use 50-GHz grid in C band and the simple nonreturn-to-zero (NRZ) modulation format. The measured Q values exhibit more than a 1.8-dB margin over the forward-error correction threshold for 10/sup -15/ bit-error-rate operation. We compare these results with point-to-point transmission of 80/spl times/10-Gb/s NRZ WDM signals over 4160 km without OADM/OXC and provide detailed characterization of penalties due to optical signal-to-noise-ratio degradation, filter concatenation, and crosstalk.  相似文献   
10.
To determine all of the components of in situ stress from core discing, both the directions and magnitudes of the principal in situ stresses must be determined for a disc of a given thickness. In this study, we analyzed the direction and magnitude of tensile stress below an HQ core stub for 11 core lengths using stress conditions under which core discing is likely to occur. First, based on an analysis of the direction of tensile stress below the core stub, we propose a method for determining directions of in situ stress from the height distribution at the periphery of the end surface of a disc. This method can be used with a disc of any thickness. Next, based on an analysis of the magnitude of tensile stress in the central part of a core, we propose a linear criterion for core discing, which can be applied to a core of any length. This criterion was in good agreement with an empirical formula obtained previously in laboratory experiments. By combining information on the direction of in situ stress and the linear criterion for core discing, we propose a method for determining all of the components of in situ stress from core discing under the assumption that vertical stress is given by the overburden stress. Finally, these methods were applied to discs obtained from a field where hydraulic fracturing was performed to measure horizontal stresses. The results showed that the azimuths of the principal stresses estimated from core discing were consistent with those of the principal horizontal stresses determined by hydraulic fracturing and that while the magnitudes of the principal horizontal stresses estimated from core discing showed a large scatter, they were similar to those determined by hydraulic fracturing.  相似文献   
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