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71.
The role of cell mediated immunity (CMI) in the pathogenesis of coxsackie B (Cox. B) viral myocarditis in the adult were immunologically investigated. The number of types of neutralizing antibody in patients with Cox. B viral myocarditis was more than that in controls. This fact suggested that these patients had a history of previous Cox. B viral infections. In the patient with Cox. B viral myocarditis, neutralizing antibody titer was increased as 20 folds by the reinfection. And also macrophage migration inhibition test showed that CMI was enhanced not only against the same type but also against the other types of Cox.B group viruses. In conclusion, it may be essential in the occurrence of adult myocarditis that the patient has been infected by Cox.B virus and immunized against the other types as well as the same type of Cox.B group viruses. CMI may also play a critical role in the occurrence of Cox.B viral myocarditis.  相似文献   
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Tan X  Matoba O  Shimura T  Kuroda K 《Applied optics》2001,40(26):4721-4727
We show that a double-random encryption technique can improve the storage capacity of an angular-multiplexed holographic memory system. In the holographic memory system, input binary images are encrypted into white-noise-like images by use of two random phase masks located at the input and the Fourier planes. These encrypted images are stored as holograms in a photorefractive medium by use of angular multiplexing. All the images are encrypted by different sets of random phase masks. Even when the angle separation between adjacent images is small enough to cause cross talk between adjacent images, original binary data can be recovered with the correct phase mask; the other reconstructed images remain white-noise-like images because incorrect masks are used. Therefore the capacity of the proposed system can be larger than that of a conventional holographic memory system without the random phase encryption technique. Numerical evaluation and experimental results are presented to confirm that the capacity of the system with random phase masks is larger than that of the conventional memory system.  相似文献   
75.
High-repetition rate 1-J green laser system   总被引:4,自引:0,他引:4  
A laser-diode-pumped high-repetition-rate zigzag slab Nd:YAG oscillator-amplifier system is developed as the pumping source of a high-average-power and terawatt Ti:sapphire chirped pulse amplification laser system. This system can produce a greater than 2-J high-energy fundamental laser pulse at a repetition rate of 100 Hz. The frequency-doubled energy with a diffusion-bonded KTP crystal is 1 J at a repetition rate of 100 Hz.  相似文献   
76.
Encrypted optical storage with angular multiplexing   总被引:3,自引:0,他引:3  
Matoba O  Javidi B 《Applied optics》1999,38(35):7288-7293
We present the first, to our knowledge, demonstration of an encrypted optical storage based on double-random phase encoding by using angular multiplexing in a photorefractive material. Original two-dimensional data are encrypted by use of two random phase codes located in the input and the Fourier planes and are then stored holographically in a LiNbO(3):Fe crystal. The retrieval of the original data can be achieved with a phase-conjugated readout scheme. We demonstrate the encryption and the decryption of multiple frames of two-dimensional digital data by using angular multiplexing. We also evaluate numerically the influence of the bandwidth of the optical system on the decrypted digital data. The bit error rate as a function of the optical system bandwidth is presented.  相似文献   
77.
Cholesterol gallstones were present in prairie dogs fed alfalfa plus corn with and without exogenous cholesterol (0.4%). The diets fed to the animals for eight weeks contained alfalfa plus corn in fixed proportions of 50∶50, 85∶15 and 15∶85 (w/w). At sacrifice, all animals were healthy but had not gained weight; no deaths occurred during the experiment. Cholesterol gallstones were present in all groups. In the absence of exogenous cholesterol, the highest stone incidence was found in the animals which received the lowest fiber (highest corn) diets (alfalfa plus corn, 50∶50, 67%; alfalfa plus corn, 15∶85, 83%). Cholesterol gallstone incidence was 100% when exogenous cholesterol was added to the alfalfa plus corn diets (50∶50 and 15∶85). No pigment gallstones were detected in any animal. Liver and plasma cholesterol concentrations were highest in the animals receiving alfalfa plus corn (15∶85) plus 0.4% cholesterol (4.29 mg/g, and 356 mg/dl, respectively). These values were lowest in animals receiving 85% alfalfa plus 15% corn without cholesterol (2.19 mg/g and 88 mg/dl, respectively). Lithogenic indices were below 1.00 in all groups. Biliary bile acids were mainly amidates of cholic acid and chenodeoxycholic acid, with the former predominating. Thus, gallstones can be formed in prairie dogs in the absence of exogenous cholesterol; gallstone incidence is reduced by dietary fiber.  相似文献   
78.
Most approaches aiming at reduction of the power flow computation time approximate the Jacobian matrix. Thus, the convergence is degraded compared to the conventional Newton method. This paper proposes a new approach for reducing the processing time by considering the fact that half of the nodes in real power systems are floating nodes that can be removed. In the conventional reduced matrix approach where the floating nodes are removed, the sparsity is lost. The method in this paper does not remove all of the floating nodes but keeps some nodes by using an optimal criterion for keeping the sparsity. The criterion is to indicate the minimum number of elements in the reduced matrix. This method has been applied to a 1000‐node test system. It was verified that the number of elements of the Jacobian has been reduced to about one‐half that of the conventional matrix. And computation time has been remarkably improved without sacrificing the convergence characteristics for the power flow computation. © 1999 Scripta Technica, Electr Eng Jpn, 129(2): 22–30, 1999  相似文献   
79.
A precise measurement was made to investigate the response of a cerium-doped GSO scintillator to thermal neutrons by means of a plastic scintillator as a neutron moderator. A delayed-coincidence technique with GSO-plastic scintillators was employed for discriminating gamma-rays. The technique was found to be very powerful in gamma-ray reduction. In the response spectrum, three sharp peaks were observed at 22, 83 and 190 keV. At 250–300 keV the response shows a small bump. This spectral structure was explained by low-lying levels of 156Gd and 158Gd. Moreover, the response was investigated in terms of time–strength interrelation.  相似文献   
80.
A reflection-type holographic disk memory system with random phase shift multiplexing is proposed. The experimental results show that a binary data page of 18x17 bits is recorded successfully at intervals of 4 mum in a Fe:LiNbO3 crystal with a thickness of 0.5 mm when six data pages are superimposed. Numerical results show that random phase modulation can improve the shift selectivity in shift multiplexing recording as well as in data security. Experimental and numerical results show that reflection-type holographic disk memory has a high potential for terabyte storage capacity as in transmission-type memory.  相似文献   
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