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We compared the automated Paragon 2000 clinical capillary zone electrophoresis (CZE) system with two manual methods, agarose electrophoresis (AGE) and cellulose acetate electrophoresis (CAE). Reference intervals in healthy adults were determined for each method. When compared with AGE and CAE, CZE gave substantially higher reference values for the alpha1-globulin fraction. With CZE, within-run precision for fraction quantitation was between 0.5% (albumin) and 4.1% (alpha1-globulin). Total precision was between 0.8% (albumin) and 5.3% (beta-globulin). Data obtained from CZE showed poor linear correlation with results obtained by AGE but good linear correlation with data from CAE. Analysis of serum from patients with inter alia inflammation, nephrotic syndrome, or polyclonal gammopathy showed that clinical information obtained by CZE is comparable with information obtained by AGE and CAE. We conclude that CZE offers a clinically reliable alternative to AGE and CAE and has the advantages of automation, higher precision, and faster turnaround time.  相似文献   
23.
We show that a nanophotonic silicon-on-insulator (SOI) platform offers many advantages for the implementation of planar concave grating (PCG) demultiplexers, as compared with other material systems. We present for the first time the design and measurement results of a PCG demultiplexer fabricated on a nanophotonic SOI platform using standard wafer scale CMOS processes including deep-UV lithography. Our PCG device has four wavelength channels with a channel spacing of 20 nm and a record-small footprint of 280times150 mum. The on-chip loss is 7.5 dB, and the crosstalk is better than -30 dB  相似文献   
24.
Total dose and displacement damage effects in a radiation-hardened CMOS APS   总被引:4,自引:0,他引:4  
A 512/spl times/512 CMOS active pixel sensor (APS) was designed and fabricated in a standard 0.5-/spl mu/m technology. The radiation tolerance of the sensor has been evaluated with Co-60 and proton irradiation with proton energies ranging from 11.7 to 59 MeV. The most pronounced radiation effect is the increase of the dark current. However, the total ionizing dose-induced dark current increase is orders of magnitude smaller than in standard devices. It behaves logarithmically with dose and anneals at room temperature. The dark current increase due to proton displacement damage is explained in terms of the nonionizing energy loss of the protons. The fixed pattern noise does not increase with total ionizing dose. Responsivity changes are observed after Co-60 and proton irradiation, but a definitive cause has not yet been established.  相似文献   
25.
There is increasing evidence that pertussis occurs frequently in adults, but there is limited information on the clinical course of this disease beyond childhood. A household contact study on the efficacy of an acellular pertussis vaccine was used to study the symptoms of pertussis in adults. Among 257 patients with pertussis identified in 121 families during a two-year period in one study center with a low whole-cell pertussis-vaccine uptake, 79 (30.7%) were adults, aged 19-83 years (mean age: 36 years) with a 1:1.8 male to female ratio. Ninety-one percent of the adults suffered from coughing (mean duration: 54 days), and in 80% this cough lasted > or = 21 days. Whoops were rare (8%), whereas cough followed by vomiting and/or choking (53%) and cough disturbing sleep (52%) were common. This is the first report to describe sweating attacks as symptom of pertussis (14%). Pharyngeal symptoms (37%), influenza-like symptoms (30%), sneezing attacks (22%), hoarseness (18%), sinus pain (16%) and headaches (14%) were also observed. Various complications were seen in 23% of the patients. In order to minimize the spread of the organism, microbiological diagnostics should be vigorously applied to all symptomatic contacts of a patient with pertussis but also to all patients with long lasting cough-irrespective of age.  相似文献   
26.
An implementation of updating techniques similar to finite element updating in structural dynamics is developed for thermal material inspection using adaptive response surfaces to approximate experimental parameters. In general, thermal models contain high nonlinearities in their parameters, which influences updating accuracies. This is further investigated in this work. Several adaptive response surface regression methods are compared: interpolation, piecewise spline and polynomial regression functions. Next, the influence of the choice of optimisation parameters is discussed and compared with several global and local optimisation routines. Finally, a well-suited regression technique is investigated which transforms the dataset to a smaller, focused response model in each optimisation loop and delivers a proper regression accuracy. This results in data-reduction for the model to be optimised.  相似文献   
27.
We present a compact planar coupler connecting two optical waveguides with highly different widths. The coupler consists of various nonperiodic waveguide sections, whose dimensions are determined using a genetic optimization algorithm. Efficiencies that exceed those of the more conventional designs with similar lengths, like gradual linear tapers, were obtained in silicon-on-insulator using 248-nm-deep ultraviolet lithography.  相似文献   
28.
Vitamin C is known for its potent antioxidant properties. Since humans lack one of the final enzymes in the biosynthesis of this vitamin, they are dependent on dietary sources for their vitamin C needs. Strawberries are good sources of vitamin C, but the vitamin is unstable during food processing, and high temperatures have shown to induce rapid degradation. As an alternative preservation technique, high-pressure processing is investigated for its potential to achieve pasteurisation and sterilisation conditions at lower process temperatures and shorter treatment times compared to thermal processing. The objective of the present study was to examine quantitatively the effect of processing on vitamin C in strawberry and raspberry matrices by comparing thermal treatments (80–140 °C) to treatments at 700 MPa (60 °C, 90 °C and 110 °C). To this end, a mechanistic model was proposed and tested to fit the degradation of ascorbic acid (AA) and the consecutive formation and degradation of dehydroascorbic acid (DHAA). AA degradation followed a biphasic course: the aerobic reaction was fast and most important, while the anaerobic reaction was slow and only perceptible at temperatures of 120 °C and up. The oxidation of AA to DHAA was slower than the subsequent degradation of DHAA in the strawberry matrix; the opposite was true in the raspberry matrix. Both temperature and pressure enhanced the degradation of vitamin C. The proposed mechanistic model provided reasonably good fits to the experimental data, only to a lesser extent for the DHAA evolution during high-pressure processing.  相似文献   
29.
Complete nucleotide sequence of a plasmid isolated from Enterobacter agglomerans has been determined. The plasmid, called pPIGDM1, consists of 2495 base pairs. The analysis of its nucleotide sequence suggested that pPIGDM1 may be a ColE1-like replicon. We confirmed this hypothesis by constructing a pPIGDM1-derived plasmid harboring the cat gene (pBW4), which could be introduced into Escherichia coli cells, and demonstrating that pBW4 cannot replicate in the absence of the polA function and that its copy number is significantly decreased in the pcnB mutant. Like some other ColE1-type replicons (e.g., pBR322), pPIGDM1-derived plasmids can be amplified both by chloramphenicol method and in isoleucine-starved relA mutants but not in relA+ bacteria. Inactivation of the putative rom gene by insertion of an amplicillin-resistance gene resulted in significant increase in pPIGDM1-derived plasmid copy number in E. coli-despite the fact that amino acid sequence of the putative RNA 1 modulator (Rom) protein is only 55.7% identical to the ColE1 analog. The pPIGDM1-derived rom-like coding sequence is also homologous to the rom-like gene present in the Proteus vulgaris plasmid pPvul. We suggest to group all these gene products into a new family called ROMS (RNA one modulators). Since a pPIGDM1-derived plasmid is compatible with other ColE1-like replicons (pMB1-, p15A, RSF1030-, and CloDF13-derived) in E. coli, one may consider pPIGDM1 as a progenitor of new cloning vehicles compatible with most (if not all) of currently used plasmid vectors. Moreover, this plasmid may serve as a source of the new rom-like gene coding for a protein useful in investigation of RNA-protein interactions. A role for the pPIGDM1 plasmid in the host strain is not known.  相似文献   
30.
An inductively coupled plasma (ICP) is analyzed by means of experiments and numerical simulation. Important plasma properties are analyzed, namely, the effective temperature inside the central channel and the mean flow velocity inside the plasma. Furthermore, the effect of torches with different injector diameters is studied by the model. The temperature inside the central channel is determined from the end-on collected line-to-background ratio in dependence of the injector gas flow rates. Within the limits of 3% deviation, the results of the simulation and the experiments are in good agreement in the range of flow rates relevant for the analysis of relatively large droplets, i.e., ~50 μm. The deviation increases for higher gas flow rates but stays below 6% for all flow rates studied. The velocity of the gas inside the coil region was determined by side-on analyte emission measurements with single monodisperse droplet introduction and by the analysis of the injector gas path lines in the simulation. In the downstream region significantly higher velocities were found than in the upstream region in both the simulation and the experiment. The quantitative values show good agreement in the downstream region. In the upstream region, deviations were found in the absolute values which can be attributed to the flow conditions in that region and because the methods used for velocity determination are not fully consistent. Eddy structures are found in the simulated flow lines. These affect strongly the way taken by the path lines of the injector gas and they can explain the very long analytical signals found in the experiments at low flow rates. Simulations were performed for different injector diameters in order to find conditions where good analyte transport and optimum signals can be expected. The results clearly show the existence of a transition flow rate which marks the lower limit for effective analyte transport conditions through the plasma. A rule-of-thumb equation was extracted from the results from which the transition flow rate can be estimated for different injector diameters and different injector gas compositions.  相似文献   
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