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51.
Yasutaka Ando  Shogo Tobe 《Vacuum》2008,83(1):102-106
In order to develop wear resistance diamond/molybdenum (Mo) hybrid coating process can be conducted in open air. Diamond deposition on the molybdenum with thermal stress buffer layer coated mild steel substrate by the combustion flame chemical vapor deposition (CFCVD) was carried out. As the thermal stress buffer layer, atmospheric plasma sprayed Mo/Fe mixture coating was deposited between Mo top coat and mild steel substrate. Consequently, crack generation and peeling off of the coating occurred due to thermal influences on the condition of Mo coated mild steel substrate in our previous study, diamond particles could be created on the Mo coating without fracture and peeling off. Besides, an additional Mo coating after diamond deposition increases the adhesion force between the diamond coating and the initial Mo coating. This encapsulation of the diamond particles between two Mo layers dramatically improves the resistance of the global coating making it strong enough to resist to the wearing test. These results demonstrate the high potential of thermal sprayed coating for the wear resistance improvement.  相似文献   
52.
A combination of anisotropic shielding effect and temperature dependence of NMR chemical shifts makes it possible to develop a supramolecular method for determination of absolute configuration of chiral compounds. The concept, theoretical derivatization, and first demonstration of this daedal noncovalent method using a host-guest system is described. This noncovalent method requires only three substrate solutions and can in principle be applied to any host-guest systems that follow the van't Hoff relation and have a clear anisotropic shielding effect based on a well-defined complex structure regardless of the extent of enantiomer selectivity.  相似文献   
53.
316L stainless steel powder was sprayed by a high-pressure high-velocity oxygen fuel (HVOF) process. Effects of powder size and the pressure in the combustion chamber on the velocity and temperature of sprayed particles were studied by using an optical instrument, first, at the substrate position. A strong negative correlation between the particle temperature and the diameter was found, whereas the correlation between the velocity and the diameter was not significant. The pressure in the combustion chamber affected the velocity of sprayed particles significantly, whereas the particle temperature remained largely unchanged. In-situ curvature measurement was employed in order to study the process of stress generation during HVOF spraying. From the measured curvature changes, the intensity of peening action and the resultant compressive stress by HVOF sprayed particles were found to increase with the kinetic energy of the sprayed particles. The results were further used to estimate the stress distribution within the coatings. X-ray stress measurement revealed that the residual stress on the surface of the HVOF coatings is low and often in tension, but the stress inside the coatings is in a high level of compression.  相似文献   
54.
This study demonstrates that the luciferin of the firefly squid Watasenia scintillans, which generally reacts with Watasenia luciferase, reacted with human albumin to emit light in proportion to the albumin concentration. The luminescence showed a peak wavelength at 540 nm and was eliminated by heat or protease treatment. We used urine samples collected from patients with diabetes to quantify urinary albumin concentration, which is essential for the early diagnosis of diabetic nephropathy. Consequently, we were able to measure urinary albumin concentrations by precipitating urinary proteins with acetone before the reaction with luciferin. A correlation was found with the result of the immunoturbidimetric method; however, the Watasenia luciferin method tended to produce lower albumin concentrations. This may be because the Watasenia luciferin reacts with only intact albumin. Therefore, the quantification method using Watasenia luciferin is a new principle of urinary albumin measurement that differs from already established methods such as immunoturbidimetry and high-performance liquid chromatography.  相似文献   
55.
56.
Detection of genetically modified organisms obtained from food samples   总被引:2,自引:0,他引:2  
Genetially modified organisms (GMOs) were explored in food samples obtained from November 2000 to March 2003 in the Tokyo area by using PCR and real-time PCR techniques. The existence of Roundup Ready Soybean (RRS) was surveyed in processed foods derived from soybeans, such as tofu, boiled soybean, kinako, nama-age, abura-age, natto, miso, soymilk and yuba. RRS was detected in 3 of 37 tofu, 2 of 3 nama-age, 2 of 3 yuba and 3 of 3 abura-age samples. The CBH351 in 70 processed corn foods, NewLeaf Plus and NewLeaf Y in 50 processed potato foods, and 55-1 papaya in 16 papayas were surveyed. These GMOs were not detected among the samples. Qualitative and quantitative analyses of RRS and genetically modified (GM) corn were performed in soybean, corn and semi-processed corn products such as corn meal, corn flour and corn grits. RRS was detected in 42 of 178 soybean samples, and the amount of RRS in RRS-positive samples was determined. The content was in the range of 0.1-1.4% in identity-preserved soybeans (non-GMO), and 49.8-78.8% in non-segregated soybeans. On the other hand, GM corns were detected in 8 of 26 samples. The amount of GM corn in GM corn-positive samples was in the range of 0.1-2.0%.  相似文献   
57.
Shape memory properties of a Ni50.3Ti29.7Hf20 (at.%) polycrystalline alloy were characterized after selected heat treatments. The effects of heat treatment temperature and time on the transformation temperatures (TTs) and temperature hysteresis were determined by differential scanning calorimetry. Thermal cycling under constant compressive stress was carried out to reveal the changes in transformation strain, temperature hysteresis, and TT as a function of stress. Isothermal stress cycling experiments were conducted to reveal the critical stresses, transformation strain, and stress hysteresis as a function of temperature. The crystal structure and lattice parameters of the transforming phases were determined by X-ray diffraction at selected temperatures. Precipitate characteristics and martensite morphology were revealed by transmission electron microscopy. Precipitation was found to alter the martensite morphology and significantly improve the shape memory properties of the Ni-rich NiTiHf alloy. For the peak aged condition shape memory strains of up to 3.6%, the lowest hysteresis, and a fully reversible superelastic response were observed at temperatures up to 240 °C. In general, the nickel-rich NiTiHf polycrystalline alloy exhibited a higher work output (≈16.5 J cm?3) than other NiTi-based high temperature alloys.  相似文献   
58.
Abstract— An evaluation technique of overall raster moiré patterns on color CRTs is developed. The technique can simulate any of the moiré modes. Generation mechanisms of various moiré patterns are clarified using the technique. It is found that the moiré patterns, no matter how complicated, consist of four basic types: barrel, pincushion, elliptical, and hyperbolic types. The patterns are found to be sensitive to the scan line distribution. When the scan lines are curved, the pattern appearing on the upper screen is different from that on the lower screen. When the scan lines are tilted, the patterns have horizontal shifts. By observing the moiré patterns, the scan line distribution can be estimated precisely.  相似文献   
59.
We reviewed 153 episodes of invasive pneumococcal disease involving 147 hospitalized patients with and without human immunodeficiency virus (HIV) disease to examine and compare epidemiologic and clinical features, capsular serotypes, and antibiotic susceptibility patterns. HIV infection was the most common risk factor for invasive pneumococcal disease. Pneumococcal disease in HIV-infected individuals was characterized by the greater frequency with which pneumonia was the source of bacteremia (90% vs. 63%) (P < .01) and an increased recurrence rate (15% vs. < 1%) (P < .01). The overall mortality rate was 12% and did not vary by HIV serostatus. Capsular-type data were available for 149 episodes; 90% of the types were among those found in the polyvalent pneumococcal vaccine. The four most common capsular types causing invasive disease were 14, 6b, 9v, and 22f; capsular type 9v was significantly more common among HIV-infected patients (P < .01). Penicillin-resistant isolates were identified in 7.2% of all cases, and their presence did not vary by HIV status; 20% of isolates from cerebrospinal fluid were resistant. The majority of the resistant isolates were of capsular type 9v. Given the worldwide increase in both HIV and penicillin-resistant pneumococcal infections, better preventative and therapeutic strategies are greatly needed.  相似文献   
60.
We evaluated the allergen inactivating effect of colloidal silica by performing enzyme-liked immunosorbent assay (ELISA) whose wells were coated with 150 ng/mL of Japanese cedar pollen allergen (Cry j 1) or mite allergen (Der f 2). The allergens were almost 100% inactivated by 100 microg/mL of colloidal silica having a particle size 5 nm, and the inactivating effect was increased by aluminum binding to the surface of the colloidal silica. The results show that colloidal silica is a promising material for allergen inactivation. Since colloidal silica forms an insoluble nondispersive solid when dried, it is expected that airborne allergens can be reduced by binding them to colloidal silica.  相似文献   
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