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51.
52.
The cubic-tetragonal transition of V-Ru alloys near 50 at % has been investigated by high resolution transmission electron microscopy. In the cubic to tetragonal transition process of thin foil specimens, we found an incommensurate modulated structure showing satellite spots near 1/4 0 1 1 positions in the electron diffraction patterns. This incommensurate structure is composed of many domains of the commensurate modulated structure with a pseudotetragonal cell of A=B=2(a 2 + c 2)1/2 and C=c, where a and c (1.07a) are the lattice constants of the tetragonally distorted CsCl-type structure. The modulation is interpreted in terms of the combination of dual elastic shear distortion waves nearly parallel to the 0 1 1 directions with the approximate wavelength of 22a. We propose a model for the incommensurate modulated structure.  相似文献   
53.
Glycan microarrays are useful tools for lectin glycan profiling. The use of a glycan microarray based on evanescent‐field fluorescence detection was herein further extended to the screening of lectin inhibitors in competitive experiments. The efficacy of this approach was tested with 2/3′‐mono‐ and 2,3′‐diaromatic type II lactosamine derivatives and galectins as targets and was validated by comparison with fluorescence anisotropy proposed as an orthogonal protein interaction measurement technique. We showed that subtle differences in the architecture of the inhibitor could be sensed that pointed out the preference of galectin‐3 for 2′‐arylamido derivatives over ureas, thioureas, and amines and that of galectin‐7 for derivatives bearing an α substituent at the anomeric position of glucosamine. We eventually identified a diaromatic oxazoline as a highly specific inhibitor of galectin‐3 versus galectin‐1 and galectin‐7.  相似文献   
54.
Several types of calcium ferrite base catalysts (Ca/Fe = 0.33–3) for propylene (C3H6) combustion were prepared. Calcium ferrite catalyst with brownmillerite crystal structure provided catalytic activity for C3H6 combustion in the temperature range of 250–450 °C. The brownmillerite phase (Ca2Fe2O5) was responsible for the formation of oxygen adspecies (O 2 ) in the surface layer below 450 °C.  相似文献   
55.
Newly synthesized nickel calcium aluminum catalysts (Ni/Ca12Al14O33) were tested in a fixed bed reactor for biomass tar steam reforming, toluene as tar destruction model compound. Four catalysts (Ni/Ca12Al14O33) were prepared with Ni loading amount from 1, 3, 5 to 7 wt%, even 1% loading catalyst also showed excellent performance. Catalysts aged experiments in the absence (60 h on stream) and presence of H2S were characterized by BET, X-ray diffraction (XRD), and Raman spectra. It was observed that Ni/Ca12Al14O33 showed excellent sustainability against coke formation due to the “free oxygen” in the catalysts. It also exhibited higher H2S-poisoning resistance property compared to the commercial catalysts Ni/Al2O3 (5%) and Ni/CaO0.5/MgO0.5. Raman spectra revealed that “free oxygen O2 and O22−” in the structure of the catalysts could be substituted by sulfur then protected Ni poisoning on some degree, but reactivation experiments by O2 flowing showed that the sulfide Ni/Ca12Al14O33 was difficult to completely restore, incorporation of sulfur in the structure only partly regain by O2. The kinetic model proposes, as generally accepted, a first-order reaction for toluene with activation energy of 82.06 kJ mol−1 was coincident with the literature data. The Ni/Ca12Al14O33 catalyst was effective and relative cheap, which may be lead to reduction in the cost of hot gas cleaning process.  相似文献   
56.
The preparation of lamellar type mesoporous silica (MPS) compact through the spark plasma sintering (SPS) and the adsorption/desorption of protein onto MPS compact are reported to be compared with those onto 2d‐hexagonal and 3d‐cubic type MPS compacts. A lamellar‐type MPS powder (MPS‐la) was prepared using triblock copolymer, PEO5 PPO68 PEO5, and was compacted in a carbon die and heated at 500°C for 5 min under uniaxial pressure. The products are referred to as MPS‐la‐500. The MPS compacts keep the lamellar type mesoporous configuration. The adsorbed amount of protein onto MPS‐la‐500 was 100 mg/g, while that on MPS‐la was 130 mg/g, and the former decreased by 23%. However, its decreasing ratio of the protein adsorption on MPS‐la‐500 was less than those of 2d‐hexagonal and 3d‐cubic type MPS compacts, which were 73 and 34%, respectively. The released amount of protein into PBS solution from MPS‐la‐500, which was soaked in the protein solution for 48 h, increased with the soaking time, while those from 2d‐ and 3d‐type MPS compacts reached to plateau for 4 h of soaking. The lamellar type MPS compact was found to be easier to absorb and release proteins, which may be due to the large aperture of the mesoporous configuration.Inspec keywords: silicon compounds, polymer blends, mesoporous materials, adsorption, plasma materials processing, proteins, sintering, powders, desorption, compaction, molecular biophysicsOther keywords: lamellar‐type MPS powder, PEO5PPO68PEO5, MPS‐la‐500, protein adsorption, lamellar type MPS compact, 3d‐cubic type MPS compact, spark plasma sintering, 2d‐hexagonal type MPS compacts, lamellar type mesoporous silicate compacts, lamellar type mesoporous silica compact, desorption, triblock copolymer, uniaxial pressure, PBS solution, protein solution, soaking time, temperature 500.0 degC, time 5.0 min, time 48.0 hour, time 4.0 hour, SiO2   相似文献   
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58.
We propose a fast surface-profiling algorithm based on white-light interferometry by use of sampling theory. We first provide a generalized sampling theorem that reconstructs the squared-envelope function of the white-light interferogram from sampled values of the interferogram and then propose the new algorithm based on the theorem. The algorithm extends the sampling interval to 1.425 microm when an optical filter with a center wavelength of 600 nm and a bandwidth of 60 nm is used. The sampling interval is 6-14 times wider than those used in conventional systems. The algorithm has been installed in a commercial system that achieved the world's fastest scanning speed of 80 microm/s. The height resolution of the system is of the order of 10 nm for a measurement range of greater than 100 microm.  相似文献   
59.
We propose free-space optical interconnections for a bookshelf-assembled terabit-per-second-class ATM switch. Thousands of arrayed optical beams, each having a rate of a few gigabits per second, propagate vertically to printed circuit boards, passing through some boards, and are connected to arbitrary transmitters and receivers on boards by polarization controllers and prism arrays. We describe a preliminary experiment using a 1-mm-pitch 2 x 2 beam-collimator array that uses vertical-cavity surface-emitting laser diodes. These optical interconnections can be made quite stable in terms of mechanical shock and temperature fluctuation by the attachment of reinforcing frames to the boards and use of an autoalignment system.  相似文献   
60.
To treat craniosynostosis, skull reshaping (such as fronto-orbital advancement) is widely performed. Surgical techniques have improved, however several problems still remain, such as postoperative relapse, late resorption, and infection. The main reason for this is probably (1) that the "craniotomized" bone for changing skull contour is used as free bone grafts and (2) that dead space between the reshaped bone and dura is created. We have developed a new method in which cranial bone is expanded gradually, together with the dura, using expansion devices. With this approach there is no extradural dead space postoperatively and the cranial bone segment remains vascularized. We have performed this procedure in 2 patients with Crouzon's disease and in 1 patient with sagittal synostosis. In the Crouzon's patients, osteotomies were performed to form a one-piece fronto-orbital bony complex without detaching the bone from the dura, and three expansion devices were applied. In the patient with sagittal synostosis, bilateral temporoparietal osteotomies were done in the same fashion and two expansion devices were applied. Expansion was started on the fourth postoperative day at a rate of about 1 mm per day. After obtaining the proper expansion, the devices were removed and the bone segments were fixed with miniplates and screws. All patients showed good results without any complications.  相似文献   
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