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71.
Acceptance sampling plans are applied for quality inspection of products. Among the design approaches of sampling plan, the most important one is to use process capability indices in order to improve the quality of manufacturing processes and the quality inspection of products. But, selection of estimators of process capability index and their sampling distribution is very important. Bayesian statistical technique can be used to obtain the sampling distribution. In this paper, a variable sampling plan is developed for resubmitted lots based on process capability index and Bayesian approach. In the proposed sampling plan, lots are inspected several times depending on the quality level of the process. In addition, this paper presents an optimization model for determining the decision parameters of developed sampling plan with regards to the constraints related to the risk of consumer and producer. Two comparison studied have been done including: First, the methods of double sapling plan (DSP), multiple dependent state (MDS) sampling plan, and repetitive group sampling (RGS) plan are elaborated, and also in order to comparing developed sampling plans, an expected number of products as average sample number (ASN) is used for different developed plans; second, a comparison study between Bayesian approach and exact probability distribution is carried out and their results are analyzed. It is observed that the ASN values of MDS sampling plan is less than ASN values of other methods, and also the ASN values of different variable sampling plans based on Bayesian approach is less than ASN values obtained using exact approach.  相似文献   
72.

Background  

Particulate air pollution has been associated with lung and cardiovascular disease, for which lung inflammation may be a driving mechanism. The pro-inflammatory cytokine, tumor necrosis factor (TNF) has been suggested to have a key-role in particle-induced inflammation.  相似文献   
73.
Preparation and Intercalation Reactions of Zn-Sn LDH and Zn-Al-Sn LDH   总被引:2,自引:0,他引:2  
Layered double hydroxide (LDH) is synthesized conventionally only with divalent and trivalent cations. In this study, Zn-Sn LDH consisting of di- and tetra-valent cations and Zn-Al-Sn LDH consisting of di-, tri- and tetra-valent cations were prepared and reacted with organic monocarboxylic, dicarboxylic and aromatic acids at 60°C. The 003 spacing of the prepared LDH (Zn-Sn-CO3) is 0.67 nm which is smaller compared to that of the usual LDH (Zn-Al-CO3) with 0.76 nm in the case of carbonate anion as the guest. Zn-Al-Sn-CO3 LDH has two 003 spacings i.e., 0.67 and 0.75 nm which belong to Zn-Sn-CO3 and Zn-Al-CO3 LDH, respectively. Analysis by DTA, TG and DTG indicated that the electrostatic force between the Zn-Sn layers and carbonate anions is larger than that of Zn-Al LDH. The carbonate anions in Zn-Sn LDH decomposed at 261°C while in the usual LDH they decomposed at 230–240°C.  相似文献   
74.
Differential biocompatibility of carbon nanotubes and nanodiamonds   总被引:1,自引:0,他引:1  
Carbon nanomaterials are being produced in increasingly larger quantities for many applications due to their novel characteristics such as enhanced thermal, electrical, mechanical, and biological properties. However, there is a lack of data on biological interactions to assess their biocompatibility before they will be accepted as non-toxic in industrial or biomedical arenas. In the present study, we examined both neuronal and lung cell lines for biocompatibility in aqueous suspensions of carbon nanomaterials, such as nanodiamonds (NDs), single- and multi-walled carbon nanotubes (SWNTs, MWNTs), and carbon black (CB), at concentrations ranging from 25–100 μg/ml for 24 h. Our results indicated that these carbon nanomaterials displayed differential biocompatibility in these two different cell lines. The greatest biocompatibility was found after incubation with NDs and both cell types followed the trend: ND > CB > MWNT > SWNT. Macrophages were found to be more sensitive to the nanomaterials with up to five times the generation of reactive oxygen species after incubation with MWNTs or SWNTs. However, there was a lack of ROS generation from either cell line incubated with ND-raw, as well as intact mitochondrial membranes, suggesting that NDs may be useful as a benchmark nanoparticle non-toxic control in replacement of CB, and should be further investigated for use in medical applications.  相似文献   
75.
76.
The Oxidation Mechanism of Pure Aluminum Powder Particles   总被引:1,自引:0,他引:1  
The oxidation mechanism of aluminum powder particles was studied by simultaneous TG–DTA analysis (under air atmosphere) at different heating rates (10, 20 and 30?°C/min) and from an ambient temperature up to 1,400?°C. Also, the rate of oxidation reaction (rate of weight gain; RTG) was obtained by the differentiation of weight gain (TGG) curve. Additionally, SEM and X-ray diffraction analysis (XRD) studies were performed on each of the above samples for their structural and phase studies. The results obtained from TG–DTA and RTG curves; microstructure and phase analysis studies indicated that the oxidation of aluminum powders occurred during five stages. On the other hand, according to the results obtained from XRD and TGG curves, aluminum particles after the thermal analysis test, even heated up to 1,400?°C, were not entirely oxidized (i.e. less than 10?%).  相似文献   
77.
End-to-end color printer calibration by total least squaresregression   总被引:3,自引:0,他引:3  
Neugebauer (1937) modeling plays an important role in obtaining end-to-end device characterization profiles for halftone color printer calibration. This paper proposes total least square (TLS) regression methods to estimate the parameters of various Neugebauer models. Compared to the traditional least squares (LS) based methods, the TLS approach is physically more appropriate for the printer modeling problem because it accounts for errors in the measured reflectance of both the primaries and the modeled samples. A TLS method based on print measurements from single-colorant step-wedges is first developed. The method is then extended to incorporate multicolorant print measurements using an iterative algorithm. The LS and TLS techniques are compared through tests performed on two color printers, one employing conventional rotated halftone screens and the other using a dot-on-dot halftone screen configuration. Our experiments indicate that the TLS methods yield a consistent and significant improvement over the LS-based techniques for model parameter estimation. The gains from the TLS method are particularly significant when the number of patches for which measured data is available is limited.  相似文献   
78.
The increased dyeability of cotton fabrics in low temperature media using two different plasma polymerisation methods was investigated in this study. In the first method, fabrics were directly treated in amine plasma (ethylenediamine or triethylenetetramine). In the second method, they were first treated in argon plasma and then immersed in an aqueous amine bath. The treated fabrics were then dyed with a reactive dye (Remazol Black B) and the colour yields and fastness properties of the resulting fabrics measured. The K/S values obtained were significantly improved when compared to the untreated fabric.  相似文献   
79.
In this study, the effects of different parameters on flow structure and flow hydraulics for combining sewer junction consisting of manhole and lateral inflow were investigated numerically. For this purpose, the effects of dimension variations, main and lateral pipe slope, angle and the joint position of lateral pipe beside manhole, manhole geometry, and the outflow rate of manhole on flow structure and energy loss coefficients were investigated. Results show that the rate of energy loss decreases by heightening the installation position of lateral pipe beside manhole. In addition, it was shown that the slope variations of main and lateral pipes and outflow rate do not affect the rate of energy loss.  相似文献   
80.
A reversed-phase HPLC method with fluorescence detection for the determination of the aflatoxins B1, B2, G1 and G2 in 42 animal feeds, comprising corn (16), soya bean meal (8), mixed meal (13), sunflower, wheat, canola, palm kernel, copra meals (1 each) was carried out. The samples were first extracted using acetonitrile:water (9:1), and was further cleaned-up using a multifunctional column. Optimum conditions for the extraction and chromatographic separation were investigated. By adopting an isocratic chromatographic system using a mobile phase comprising acetonitrile:methanol:water (8:27:65, v/v/v), the separation of the four aflatoxins was possible within 30 min. Recoveries for aflatoxins B1, B2, G1 and G2 were 98 ± 0.7%, 95 ± 1.0%, 94 ± 3.6% and 97 ± 4.3%, respectively. The results show that eight samples (19%) were contaminated with aflatoxins, ranging from 6.5 to 101.9 ng g?1. Total aflatoxin levels in three samples exceed the legal limits of many countries of 20 ng g?1.  相似文献   
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