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81.
Strigolactones are low-molecular-weight phytohormones that play several roles in plants, such as regulation of shoot branching and interactions with arbuscular mycorrhizal fungi and parasitic weeds. Recently, strigolactones have been shown to be involved in plant responses to abiotic and biotic stress conditions. Herein, we analyzed the effects of strigolactones on systemic acquired resistance induced through salicylic acid-mediated signaling. We observed that the systemic acquired resistance inducer enhanced disease resistance in strigolactone-signaling and biosynthesis-deficient mutants. However, the amount of endogenous salicylic acid and the expression levels of salicylic acid-responsive genes were lower in strigolactone signaling-deficient max2 mutants than in wildtype plants. In both the wildtype and strigolactone biosynthesis-deficient mutants, the strigolactone analog GR24 enhanced disease resistance, whereas treatment with a strigolactone biosynthesis inhibitor suppressed disease resistance in the wildtype. Before inoculation of wildtype plants with pathogenic bacteria, treatment with GR24 did not induce defense-related genes; however, salicylic acid-responsive defense genes were rapidly induced after pathogenic infection. These findings suggest that strigolactones have a priming effect on Arabidopsis thaliana by inducing salicylic acid-mediated disease resistance.  相似文献   
82.
A robust controller for insulin pumps based on H-infinity theory   总被引:1,自引:0,他引:1  
The feedback control of insulin pumps for diabetic patients is discussed. Because the parameters in the mathematical model of the blood glucose dynamics present a considerable amount of uncertainty, the H-∞ framework is well suited for the design of controllers that take into account a nice compromise between robust closed-loop regulation of a constant set point and performance expressed in terms of peak values of the plasma glucose concentration  相似文献   
83.
Carcinosarcoma of the esophagus is a rare malignant tumor with both carcinomatous and sarcomatous components. We present 3 cases of carcinosarcoma of the esophagus and discuss the histogenesis of the tumors. We performed immunohistochemical studies using various antibodies: anti-cytokeratin, anti-vimentin, anti-smooth muscle actin, anti-p53, and MIB 1 reacting with Ki-67 nuclear antigen.  相似文献   
84.
85.
We demonstrate, for the first time, the characteristics of an InP/InGaAs HBT-compatible pin-PD and a monolithically integrated pin/HBT photoreceiver. The pin-PD can produce a short pulse with an FWHM of 80.8 ps followed by an elongated tail, when illuminated by optical pulses with an FWHM of 40 ps and a wavelength of 1.3 μm. The fall time of the output is determined by the transit time of holes generated in the n +-InGaAs layer. The monolithically integrated photoreceiver, consisting of the pin-PD and a transimpedance preamplifier, can operate at 2.5 Gb/s with a sensitivity of -9.8 dBm. This performance was mainly limited by the characteristics of the pin-PD  相似文献   
86.
87.
The mechanism of anodic oxidation of cyanide on the graphite electrode was investigated by voltammetry, controlled potential coulometry, constant potential electrolysis and colorimetry. Cyanide was oxidized at the first order with respect to cyanide ion and at the zero order with respect to hydroxyl ion on the rate determining step. On the other hand, the result of controlled potential coulometry indicated that napp was 2 at high OH? concentration, but approached unity at low OH? concentration. When constant potential electrolyses were carried out using electrolytes containing concentrated OH? and diluted OH?, the presence of cyanate was confirmed in both products. In addition to this, since oxalate anion was detected in the product at low OH? concentration, cyanogen, (CN)2 was considerable to form an intermediate. Based on these results, two probable mechanisms were proposed. The discharge of cyanide ion is considerable to determine the overall rate in both mechanisms. Furthermore, it is informed that the side reaction forming oxalate anion proceeds at low OH? concentration.  相似文献   
88.
Spray-formed Al–Fe alloys having undergone high-speed deformation were examined under a high-voltage electron microscope. Two types of specimens were examined; one containing fine Al13Fe4 particles, and the other containing large particles. In the former specimen, deformation is found to proceed in three patterns, depending on specimen thickness and strain rate: (1) without deformation of the Al13Fe4; (2) breaking of the Al13Fe4; or (3) melting of the Al13Fe4. Local melting is found to alter some of the Al13Fe4 particles, to impart five-fold symmetry in diffraction or an amorphous structure. In the latter specimen, introduction of glide dislocations enabled us to determine a shear system in the mc102 monoclinic c2/m crystal of Al13Fe4. On the bases of these observations, the mechanism of high-speed deformation is discussed while taking into account the highly stressed and/or heated states of Al13Fe4 embedded in Al matrix.  相似文献   
89.
In this study, we examine the relationship between harmonic voltage injection, acoustic noise, and position estimation performance in a PMSM when a position‐sensorless control method involving harmonic voltage injection is used at low speeds. Further, we propose a novel control method for voltage injection; this method can be used to reduce acoustic noise in the motor. The proposed control method is verified by performing numerical simulations and carrying out experiments using a four‐pole, 2‐kW, 2100‐rpm IPMSM (interior permanent‐magnet synchronous motor). © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 179(3): 49–56, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21246  相似文献   
90.
Electrical properties of halogen-doped CdTe layers grown on Si substrates using iodine and chlorine dopants are presented. No change in electrical properties of the layers was observed with chlorine as a dopant. However, doping with iodine resulted in highly conductive n-type layers or highly resistive p-type layers depending upon the growth conditions, even though a similar amount of dopant was introduced into the growth chamber. Layers grown at 560°C, with a vapor-phase Te/Cd precursor ratio of 3.0, were p-type. The resistivity of the layers remained unchanged for low dopant supply rates, but increased abruptly when the dopant supply rate was increased beyond a certain value. On the other hand, layers grown at 325°C with Te/Cd ratios from 0.1 to 0.25 were n-type. A maximum free electron concentration of 1.3 × 1017 cm−3 was obtained at room temperature. The types and conductivities of the grown layers were strongly dependent on the growth conditions.  相似文献   
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