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61.
We examine a technique for enhancing the voltage contrast (VC) of a failure analysis (FA) tool, defect review scanning electron microscope (DR-SEM). For an SRAM, we demonstrate a dependence of gate-leak VC on the relative angle (RA) between the direction of beam scanning by the FA tool and the lengthwise direction of the gate electrode. Experimental results show that better VC results are obtained when RA is zero, in other words, a beam's scan-line is parallel with the SRAM gate. We propose a simple qualitative resistor-capacitor model to explain this phenomenon. With the help of this VC enhancement technique of the FA tool, we could tune the electron beam inspection (EBI) recipe to an appropriate condition quicker. The cycle time of EBI recipe tuning was shortened from five to two days. As a result, correct EBI evaluation results of countermeasure experiments led us to a yield enhancement solution within a shorter period of time.  相似文献   
62.
We describe our experience with extracorporeal shock wave lithotripsy (ESWL) in three patients with coagulation disorders (one case of hemophilia A, and two cases of thromboasthenia). We successfully performed ESWL using factor VIII or transfusion of platelets without any severe hemorrhagic complications, such as perirenal and subcapsural hematomas. We consider that adequate supplement of coagulation factor or platelets may lower the risk of hemorrhagic complications in coagulopathic patients who undergo ESWL.  相似文献   
63.
The authors report on a case of a solitary liver abscess due to Listeria monocytogenes in a 53-year-old diabetic white male and review all published cases of solitary listerial abscesses of the liver. L. monocytogenes is a rare cause of solitary liver abscess which occurs in elderly patients with diabetes mellitus. The clinical signs are variable and often mimic malignancy, with epigastric pain, night sweats and weight loss. Prevalent features are poor control of glycemia, temperature up to 38.5 degrees C and elevated alkaline phosphatase. Optimal treatment includes percutaneous drainage of the hepatic abscess and antibiotic therapy with an aminopenicillin or trimethoprim/sulfamethoxazole. Outcome of the reviewed patients was favourable with no mortality and no relapse of the disease.  相似文献   
64.
We describe the design and performance of a series of fast, precise current sensing noise thermometers. The thermometers have been fabricated with a range of resistances from 1.290  $\Omega $ down to 0.2 m $\Omega $ . This results in either a thermometer that has been optimised for speed, taking advantage of the improvements in superconducting quantum interference device noise and bandwidth, or a thermometer optimised for ultra-low temperature measurement, minimising the system noise temperature. With a single temperature calibration point, we show that noise thermometers can be used for accurate measurements over a wide range of temperatures below 4 K. Comparisons with a melting curve thermometer, a calibrated germanium thermometer and a pulsed platinum nuclear magnetic resonance thermometer are presented. For the 1.290  $\Omega $ resistance we measure a 1 % precision in just 100 ms, and have shown this to be independent of temperature.  相似文献   
65.
The following synthetic peptides were made as immunogens for development of a zona-based contraceptive vaccine: P1, KQPFWLLQGGASRAETSVQPVLVE [amino acids (aa) 23-45 with an additional K at the N-terminus]; P2, FSEEKLVFSLRLMEENC (aa 164-179 with an additional C at the C-terminus and T170 replaced by V); and P3, CSFSKSSNSWFPVEGPADICQCC (aa 300-322). The aa are numbered on the basis of bonnet monkey ZP3 precursor protein. Antibodies against an additional peptide P4, KGDCGTPSHSRRQPHVVSQWSRSA (aa 324-347), significantly inhibits human sperm-oocyte binding. In addition, antibodies against cocktail of peptide-diphtheria toxoid conjugates also significantly inhibit the binding of spermatozoa to zona pellucida in a hemizona assay. These results will further help in the design of an immunocontraceptive vaccine based upon synthetic peptides corresponding to ZP3.  相似文献   
66.
Cross-sectional views of intact biomembranes and synthetic lipid bilayer membranes were observed by electron cryomicroscopy using spontaneous orientation of disk-shaped membranes; purple membrane, thylakoid membrane, synthetic phospholipid membrane and a microcrystalline sheet made of Er-binding polypeptide were observed. The membranes were observed fully hydrated, embedded in vitreous ice, and their self-orientation was most probably caused by repulsion between their hydrophobic edges and their hydrophilic environment which forced their edges to be exposed to the air-water interface. The cross-sectional profiles of the native biomembranes were asymmetric and characteristic, whilst those of the synthetic membranes were symmetric and predictable by a simple model. Simple Fourier analysis showed that the cross-sectional images retained structural information up to a medium resolution.  相似文献   
67.
68.
Membrane proteins are important research targets for basic biological sciences and drug design, but studies of their structure and function are considered difficult to perform. Studies of membrane structures have been greatly facilitated by technological and instrumental advancements in electron microscopy together with methodological advancements in biology. Electron crystallography is especially useful in studying the structure and function of membrane proteins. Electron crystallography is now an established method of analyzing the structures of membrane proteins in lipid bilayers, which resembles their natural biological environment. To better understand the neural system function from a structural point of view, we developed the cryo-electron microscope with a helium-cooled specimen stage, which allows for analysis of the structures of membrane proteins at a resolution higher than 3 ?. This review introduces recent instrumental advances in cryo-electron microscopy and presents some examples of structure analyses of membrane proteins, such as bacteriorhodopsin, water channels and gap junction channels. This review has two objectives: first, to provide a personal historical background to describe how we came to develop the cryo-electron microscope and second, to discuss some of the technology required for the structural analysis of membrane proteins based on cryo-electron microscopy.  相似文献   
69.
Piezoresponse force microscopy was conducted on a polished slice of the perovskite oxynitride ceramic BaTaO2N after ammonolysis at a bias voltage of?±?10?V. The ceramic surface was relatively porous because it was readily hydrolyzed by ambient humidity. While there was no piezoresponse on the surface of the ultrathin slice, a piezoresponse was clearly observed just below the surface of a thick slice. The response was enhanced in a denser sample. It increased with measuring voltage up to 7?V, and then gradually decreased up to 9?V. The response also gradually decreased with time but persisted even after 150?min at a measuring voltage of 6?V. Microstructural characterization revealed well-sintered grains, about 100?nm in size, in a relatively dense BaTaO2N structure. High-porosity BaTaO2N did not show any piezoresponse because its porous surface was easily hydrolyzed. A weak piezoresponse was observed for an electrically conductive slice obtained from deep inside a relatively dense BaTaO2N ceramic after ammonolysis.  相似文献   
70.
Cesium was recovered from soil samples obtained in Fukushima prefecture. Isotopic analysis of Cs was performed by γ-spectrometry to determine the activity ratio of 134Cs/137Cs and thermal ionization mass spectrometry was used to determine the isotopic ratios of 133Cs/137Cs and 135Cs/137Cs. The analytical results showed that both the activity ratio of 134Cs/137Cs and the isotopic ratio of 135Cs/137Cs were within the expected values for the Fukushima Daiichi Nuclear Power Plant estimated using the ORIGEN-II code, suggesting that most of the radioactive Cs in the soil sample originated from the Fukushima Daiichi Nuclear Power Plant. The concentration of 137Cs and the contribution of radioactive Cs from global fallout were correlated to the distance from the Fukushima Daiichi Nuclear Power Plant, while the contribution of radioactive Cs from each reactor did not show any similar distance dependence.  相似文献   
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