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91.
离子注入机ⅦSta平台对≤130 nm尺寸CMOS工艺在整个能量和剂理范围提供单片注入.这些注入机的特征是硬件和设计原理通用,并包含离子束注入角控制、剂量测定和终端站设计.这种方法对重叠剂量范围能使工艺可完全互换,并对引起制造所有权成本(COO)降低提供了最大的灵活性.一个完整工艺的透彻性需要剂量形貌特征精确匹配,并很好地说明这一能力、晕圈效应、VT和延展注入.此外,也证实了ⅦSta平台的单片设计消除了缺陷来源,确保了无风险工艺互换. 相似文献
92.
93.
Karun Mehta Jan Fong Jue Anil V. Virkar 《Journal of the American Ceramic Society》1990,73(6):1777-1779
Ceria- and yttria-doped tetragonal polycrystalline zirconia ceramics were ground at temperatures as high as 1100°C. X-ray diffraction revealed that the intensity ratio I (002) / I (200) increased (to as high as ∼4.5) compared with that from the as-sintered surfaces (∼0.55). The enhancement in I (002) / I (200) at temperatures well above the m → t transition temperature shows that it is not related to transformation, reversible or otherwise, but can be explained by ferroelastic domain switching. 相似文献
94.
Phosphoglycosylation catalyzed by UDP-GlcNAc:Ser-protein N-acetylglucosamine-1-phosphotransferase (Ser:GlcNAc phosphotransferase) adds GlcNAcalpha-1-P to peptidyl-Ser of selected Dictyostelium discoideum proteins. Lysosomal cysteine proteinase (CP), proteinase-1(CP7), is the major phosphoglycosylated protein in bacterially grown amoebae. GlcNAc-1-P is added within a Ser-rich domain containing SSS, SGSG, or SGSQ repeated motifs that are not found in other papain-like CPs. We studied the substrate specificity of the transferase using peptides containing these motifs and 12 other peptides with one or more Ser residues. Phosphoglycosylation is comparable for all three Dictyostelium CP motifs, but it is not restricted to them. Flanking residues in the other peptides strongly influence phosphoglycosylation efficiency. Dictyostelium microsomal membranes also phosphoglycosylate endogenous acceptors, and some of these acceptors occur as an 18 S complex with the transferase. CP-serine motif peptides inhibit endogenous acceptor phosphoglycosylation weakly (30-40%) at 800 microM, whereas catalytically inactive proteinase-1(CP7) and other non-phosphoglycosylated eukaryotic CPs, lacking the serine domain, inhibit transferase activity at 1-4 microM. SDS denaturation destroys the inhibitory potential of all CPs showing that transferase recognizes a conformation-dependent feature that is shared by all. Proteinase-1(CP7) expressed in Escherichia coli lacks GlcNAc-1-P, but it is a substrate for Ser:GlcNAc phosphotransferase, Km = 5.6 microM. Thus, Ser:GlcNAc phosphotransferase recognizes both acceptor peptide sequences and a conformational feature of eukaryotic CPs. This may be physiologically important for establishing or maintaining non-overlapping groups of GlcNAc-1-P- and Man-6-P-modified Dictyostelium proteins that reside in functionally distinct endo-lysosomal vesicles. 相似文献
95.
Raghavendra R. Adharapurapu Kenneth S. Vecchio Fengchun Jiang Aashish Rohatgi 《Metallurgical and Materials Transactions A》2005,36(11):3217-3236
The fracture toughness and resistance-curve (R-curve) behavior of Ti-Al3Ti metal-intermetallic laminate (MIL) composites have been studied in the crack-divider orientation, by examining the effect
of ductile-laminate-layer thickness and volume fraction. The MIL composites were fabricated in open air by a novel one-step
process, and the final structure consists of alternating layers of ductile Ti and brittle Al3Ti. Such a laminate architecture in conjunction with a relatively low volume fraction of tougher Ti (18 to 40 pct) was seen
to augment the fracture toughness of the inherently brittle intermetallic by over an order of magnitude. Additionally, as
a result of their low density, MIL composites exhibit a specific fracture toughness (K/ρ) on par with tougher but relatively denser ductile metals such as high-strength steel. Such vast improvements may be rationalized
through the toughening provided by the ductile Ti layers. Specifically, toughening was obtained through plastically stretching
the intact ductile Ti layers that formed bridging zones in the crack wake, thus reducing the crack driving force. Such toughening
resulted in R-curve behavior, and the toughness values increased with an increase in the volume percentage of Ti. Weight-function methods
were used to model the bridging behavior, and they indicated that large bridging zones (∼2 to 3 mm) were responsible for the
observed increase in toughness. The role of large-scale bridging (LSB) conditions on the resistance curves is explored, and
steady-state toughness (K
SS
) values are estimated using small-scale bridging (SSB) approximations. A new approach to gage the potential of laminate composites
in terms of their true fracture-toughness values as determined from a cyclic crack-growth fatigue test is proposed, wherein
small-scale specimens can be utilized to obtain fracture-toughness values. 相似文献
96.
Bhagwati Bishnoi P.K. Mehta C.J. Panchal M.S. Desai Ravi Kumar V. Ganesan 《Materials Chemistry and Physics》2011
We present the preliminary results of temperature and frequency dependent dielectric measurements on Ba(Co1/3Nb2/3)O3 (BCN) thin films. These films were prepared on indium tin oxide (ITO) coated glass substrates by the pulse laser deposition (PLD) technique. It exhibits single-phase hexagonal symmetry. These films were irradiated with Ag15+ (200 MeV) and O7+ (100 MeV) beams at the fluence 1 × 1011, 1 × 1012, and 1 × 1013 ions/cm2. On irradiating these films, its dielectric constant (?′) and dielectric loss (tan δ) parameters improve compared to un-irradiated film. Compared to O7+ irradiation induced point/cluster defects Ag15+ induced columnar defects are more effective in reducing/pinning trapped charges within grains. The present paper highlights the role of swift heavy ion irradiation in engineering the dielectric properties of conductive samples to enable them to be useful for microwave device applications. 相似文献
97.
In this paper quantitative imaging of biological cells using high-resolution full-field optical coherence microscopy (FF-OCM) is reported. The FF-OCM was realized using a swept-source system, a Mirau interferometer, and a CCD camera (a two-dimensional detection unit). A Mirau-interferometric objective lens was used to generate the interferometric signal. The signal was analyzed by a Fourier analysis technique. Optically sectioned amplitude images and a quantitative phase map of biological cells such as onion skin and red blood cells (RBCs) are demonstrated. Further, the refractive index profile of the RBCs is also presented. For the 50× Mirau objective, the experimentally achieved axial and transverse resolution of the present system are 3.8 and 1.2 μm, respectively. The CCD provides parallel detection and measures enface images without X, Y, Z mechanical scanning. 相似文献
98.
The adsorption equilibrium moisture contents for red chilli were determined experimentally in relative humidity range of 11–97% at the temperatures of 20, 30, 40, and 50°C. Six equilibrium moisture content models were fitted to the experimental data. The modified Oswin model was the best fitted equation for relative humidity range of 11–97% for the adsorption data of red chilli. 相似文献
99.
Factors that influence colony morphology are of crucial importance for drug development as well as for understanding the virulence of Mycobacterium avium complex (MAC) strains. The MAC 101 strain used in the present study grows as smooth transparent (SmT) colonies that tend to become opaque and pigmented when incubated for long periods of time. However, when MAC was passaged in animals, two types of colonies were recovered. The new rough transparent (RgT) colony morphology appeared more flat and transparent, having a central spot, irregular edges at times, and a dry, granular appearance like that of the rough mutants. In animal studies, the RgT bacilli multiplied at a much faster rate than that of the SmT bacilli, causing 60-80% mortality compared with the 10% mortality observed in mice infected with SmT. In vitro studies indicated that the SmT MAC did not grow and multiply as well in resident peritoneal macrophages as the RgT MAC did. The two morphotypes did not differ in their growth ratesin vitro but the RgT MAC failed to reduce dimethylthiazol-diphenyltetrazolium bromide (MTT), alamar blue and neutral red, suggesting that there might be significant changes in the cell wall or elsewhere causing changes in cellular permeability. These two morphotypes could serve as models for studying the biochemical markers or the identification of factors responsible for the virulence of the MAC. 相似文献
100.