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81.
Yasuhiro Kobayashi Masaaki Ohkita Michio Inoue 《Mathematics and computers in simulation》1978,20(4):285-290
In the previous papers [1][3], fractional powers were used to approximate elementary functions and their usefulness was proved with experimental results. In the present paper, some further investigations are reported. That is, elliptic integrals in Legendre's canonical form and Bessel functions are approximated by fractional powers. As the fractional power approximation, is discussed. When all coefficients c0, c1, c2, p are properly assigned, the accuracy of this approximation becomes comparable to that of the Chebyshev approximation using polynomials up to the third degree. 相似文献
f(x) c0 + c1x + c2xp
82.
The shape and size of pitch molecules were discussed through the measurements of the intrinsic viscosity [η] and the diffusion coefficient D of molecular weight fractionated petroleum pitches in dilute chloroform solutions, where [η] was measured by an Ubbelohde viscometer, and D by Northrup-McBain diaphragm cells. Hydrodynamical considerations on the [η] vs D relationship lead to a conclusion that pitch molecules examined are of 3-dimensional structure, the axial ratio being 1–3 under the oblate ellipsoid assumption, and their sizes being about 10 ~ 20 Å in equatorial diameter. 相似文献
83.
The thermal dilatation in (NH3 ·CH3) SnCl6, (NH3 · C2H5) SnCl6 and [N(CH3)] SnCl6 was measured, and as the results it has turned out that (NH3 6·C2H5) SnCl6 and [N(CH3)4]2 SnCl6 undergo the first order transitions at 128 K and 158 K, respectively. The low temperature phases of (NH · C2H5) SnCl6 and [N(CH3)4]2 SnC16 are found to be monoclinic and tetragonal, respectively, No phase transition was observed in (NH3 ·CH3)2 SnCl6 down to 77 K. 相似文献
84.
85.
Bosoon Park Michio Kise William R. Windham Kurt C. Lawrence Seung C. Yoon 《Sensing and Instrumentation for Food Quality and Safety》2008,2(3):208-214
Previous studies demonstrated a hyperspectral imaging system has a potential for poultry fecal contaminant detection by measuring
reflectance intensity. The simple image ratio at 565 and 517 nm images with optimal thresholding was able to detect fecal
contaminants on broiler carcasses with high accuracy. However, differentiating false positives from real contaminants, especially
cecal feces were challenging. Further image processing such as textural analysis in the spatial domain was able to reduce
false positive errors. In this study, textural analysis of hyperspectral images was conducted to improve detection accuracy
by reducing false positives. Specifically, textural analysis with co-occurrence matrix of hyperspectral images performed well
to identify “true” contamination. In addition, co-occurrence matrix textural features including average, variance, entropy,
contrast, correlation, moment of poultry hyperspectral images were investigated for selecting optimal features to represent
contamination. Image pre-processing with co-occurrence textural analysis, specifically mean of co-occurrence textural feature
from the matrix (0° angle and distance equals to one) followed by image ratio was able to improve fecal detection accuracy
without additional optical filters that increase cost for system hardware of multispectral imaging system for on-line application.
Mention of trade names or commercial products in this article is solely for the purpose of providing specific information
and does not imply recommendation or endorsement by the U.S. Department of Agriculture. 相似文献
86.
This is the first report to reveal the particle-water distribution of nitropolycyclic aromatic hydrocarbons (NPAHs) and to discuss their potential risks and utility as indicators of diesel vehicle exhaust particles (DEP). Time-series samples of runoff were collected from a highway, and NPAHs and polycyclic aromatic hydrocarbons (PAHs) were determined by gas chromatography-mass spectrometry (GC-MS) to study their dynamic behavior. The concentrations of total NPAHs ranged from 11 to 73 ng/L in particulate phase (>0.7 mcirom) and from 2.3 to 4.9 ng/L in dissolved phase (<0.7 microm). Like their PAH analogs, most (81-97%) NPAHs were associated with particulate matter. The organic carbon-normalized in situ partition coefficients (Koc') of NPAHs observed in runoff events (10(5.8-6.3) for 2-nitrofluoranthene and 10(5.8-6.2) for 1-nitropyrene [1-NP]) were more than 1 order of magnitude higher than those expected from their Kow, indicating great affinity for particulate matter such as soot. Concentrations of PAHs and NPAHs adjusted by potency equivalency factors and induction equivalency factors showed that the potential risks of NPAHs were smaller than those of PAHs by a factor of more than a hundred for the particulate phase and morethan fourforthe dissolved phase. Comparison of concentrations and compositions of NPAHs and PAHs among runoff, DEP, gasoline vehicle exhaust particles, boiler exhaust particles, and aerosols suggested that the ratio of 1-NP to total PAHs (1-NP/PAH) is a useful indicator of DEP for source apportionment of PAHs among traffic-related sources. Source-apportionment of PAHs in the runoff by 1-NP/PAH and methylphenanthrene/phenanthrene ratios suggested that most PAHs in the runoff except the second flush peak were derived from DEP but that other pyrogenic sources contributed to the particles at the second flush and thus to the overall runoff particles. 相似文献
87.
Ngamwongsatit P Buasri W Pianariyanon P Pulsrikarn C Ohba M Assavanig A Panbangred W 《International journal of food microbiology》2008,125(3):352-356
Eight new pairs of PCR primers were designed and efficiently detect eight toxin genes (hblC, hblD, hblA, nheA, nheB, nheC, cytK, and entFM) in 411 B. cereus strains (121 food- and 290 soil isolates) and 205 B. thuringiensis strains (43 serovars, 10 food- and 152 soil isolates). According to the presence of these eight toxin genes, they were divided into four groups among the total 616 isolates. In Group I, all eight genes occurred simultaneously in 403 (65.42%) isolates, while Group II (134 isolates or 21.75%) and Group III (46 isolates or 7.47%) were devoid of hblCDA and cytK, respectively. In Group IV, there were thirty-three isolates which lacked both hblCDA and cytK. The presence of hblCDA in B. thuringiensis strains (86.80%) was significantly higher (P<0.05) than in B. cereus strains (66.18%) whereas no significant difference in nheABC, cytK and entFM occurrence was detected between both bacterial groups. Both nheABC and entFM genes were found in all B. cereus and B. thuringiensis strains (616 strains in total), while the cytK gene could be detected in 365 (88.80%) of the B. cereus and 172 (83.90%) of the B. thuringiensis strains. None of the 616 tested strains showed the presence of only a single or two genes in either the hbl or nhe operons. The eight primer pairs designed for this multiplex PCR allowed rapid detection of eight toxin genes from boiled cells with high sensitivity, gave 100% reproducibility, and did not cross-react to 32 other bacterial strains. 相似文献
88.
Makoto Ishiguro Nobuhiko Ichihara Yujiro Yanai Michio Nagai Katsuyuki Takada Yoichi Suga Yoji Ito 《Journal of the Society for Information Display》2018,26(4):208-213
We have successfully developed a cosmetic film with polymerized cholesteric material. The film features a variety of colors by helical pitch gradients, diffusive texture, and arbitrary color patterns. It hides the display when turned off, and transmits display images when turned on. We believe it could change the display in the OFF‐state from the conventional black wall to specially designed decorations. In addition, they can be applied to hidden sensors. 相似文献
89.
Pore structure of carbons coated on ceramic particles 总被引:1,自引:0,他引:1
Michio Inagaki Shingo Kobayashi Fumi Kojin Nobuyuki Tanaka Takahiro Morishita Beata Tryba 《Carbon》2004,42(15):3153-3158
Pore structure of carbon coated on ceramic particles by carbonization of precursor in a powder mixture at 900 °C was studied by focusing on the effects of substrate ceramics (MgO, TiO2 and various phases of Al2O3) and of carbon precursor (poly(vinyl alcohol) (PVA), poly(ethylene terephthalate) (PET) and hydroxyl propyl cellulose (HPC)). By dissolving substrate MgO particles, carbon coated was found to have a high BET surface area, more than 1000 m2/g, which was almost the same as the value estimated from apparent surface area measured on carbon-coated MgO particles under the assumption of zero surface area of the substrate. The carbon separated was found to be rich in micropores from the analyses by DFT method and αs plot. The dependence of the BET surface area on the amount of carbon coated on TiO2 with a high surface area was the same for three carbon precursors, although the carbon yields from the precursors were slightly different. Porous Al2O3 substrates, γ-Al2O3as-received and that formed from Al(OH)3 during carbonization, gave a high BET surface area, but dense Al2O3, α-Al2O3, gave a low surface area. 相似文献
90.
Yamamoto N Muramoto A Yoshinaga J Shibata K Endo M Endo O Hirabayashi M Tanabe K Goto S Yoneda M Shibata Y 《Environmental science & technology》2007,41(18):6357-6362
We compared the status of carbonaceous aerosols in Tokyo before and after the implementation of a diesel vehicle regulation intended to reduce the quantity of particulate carbon from diesel engines in one of the largest scale ever attempts at vehicle exhaust control. Radiocarbon (14C) in elemental carbon (EC) and total carbon (TC) were analyzed to identify fossil fuel carbonaceous particles emitted from diesel-powered vehicles. One-sided paired-month t-tests showed no distinct difference in the absolute concentrations of particles in terms of total mass (19.5 to 18.0 microg m(-3); p = 0.321), EC (3.6 to 3.3 microg m(-3); p = 0.272), and TC (6.3 to 6.2 microg m(-3); p = 0.418) for the finest particles (d(a) < 1.1 microm) after the implementation of the regulation. The ratios of the concentrations of the chemical constituents were, however, altered after the regulation. EC/TC was significantly decreased from 56.7% to 50.2% (p = 0.039). Although it was not statistically significant, the percentage of fossil carbon in EC also decreased (67.8% to 63.8%; p = 0.104). Since EC is predominantly of combustion origin, the observed decrease was likely due to the decrease in fossil EC emissions from diesel-powered vehicles. The decrease in EC/TC after the implementation of the regulation was also likely to have resulted from attachment to diesel vehicle exhaust systems of particulate filters as required as part of the regulation by the Tokyo Metropolitan Government. The EC/TC of fossil carbon of the finest particles decreased from 66.2% to 55.2% (p = 0.066), but EC/TC of biomass carbon did not decrease but rose slightly from 43.6% to 44.5% (p > 0.5). Thus, the relative ratios of components of carbonaceous aerosol particles, such as 14C, could provide a better understanding of the atmospheric pollution status, despite short-term fluctuations, than do measurements of absolute concentrations. 相似文献