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161.
K. Tanaka M. Tateda Y. Inoue 《Photonics Technology Letters, IEEE》1996,8(7):915-917
We propose a new method for measuring the individual attenuation distribution of passive branched optical networks and describe our experimental results. This test method employs two techniques. One is a passive optical distribution technique, whereby communication light is uniformly distributed to all branched fibers, and test lights are distributed to each branched fiber according to their wavelength. The other is an attenuation distribution measurement technique using an optical time domain reflectometer (OTDR) which can control the test light wavelength. 相似文献
162.
Highly oriented isotactic polypropylene with ultrahigh modulus was prepared by means of the zone drawing method proposed by Kiho and Asai. This method features heating a limited portion of the sample. The maximum value of modulus attained was 15 GPa, which corresponds to about half the crystal modulus along the molecular axis evaluated by the x-ray method. Such an ultrahigh modulus was obtained for a sample of medium molecular weight by inducing necking in the heater and subsequently cooling the sample at lower temperature. The loss tangent peak with the initiation of micro-Brownian motion of amorphous chains became progressively smaller and broadened more at higher temperatures with increasing draw ratio. Orientation function of the crystal c-axis increased with draw ratio λ in the region below λ = 9, but reached a constant value, 0.995, in the region above λ = 9. The modulus increased with draw ratio in all ranges of the draw ratio. 相似文献
163.
A novel method of indirect deposition by means of a focused ion beam (FIB) is utilized to develop metal/insulator/semiconductor nanowire core-shell structures. This method is based upon depositing an annular pattern centered on a nanowire, with secondary deposition then coating the wire. Typical cross-sectional deposition area increments as a function of ion doses are 1.3 × 10(-2)?μm(2)?nC(-1) for Pt and 3.5 × 10(-2)?μm(2)?nC(-1) for SiO(2). The structures are examined with a transmission electron microscope (TEM) using a new nanowire TEM sample preparation method that allows direct examinations of individually selected core-shell nanowires fabricated under different indirect FIB deposition conditions. Elemental analyses by means of energy dispersive x-ray spectroscopy and electron energy filtered TEM imaging verify the deposition of SiO(2) and Pt layers. Relatively uniform Pt and SiO(2) coatings on individual GaP nanowires can be achieved with overall thickness deviation of about 10% for deposition up to 25-30?nm thick Pt or SiO(2) shells. It should be possible to extend this approach to any nanowire/nanotube system, and to a wide range of coatings in any desired layer sequences. 相似文献
164.
The gelation mechanism of β-lactoglobulin (bLG) aqueous solutions was investigated by dynamic light scattering (DLS) and small-angle neutron scattering (SANS). Temperature- and pressure-jump experiments, respectively, abbreviated as T-jump (from 20 to 75 °C; T-jump) and P-jump (from 0.1 to 315 MPa) were carried out and the time evolution of gel structure was monitored by DLS and SANS as a function of time. The gelation threshold was determined by DLS as the point when nonergodicity appeared. In the case of T-jump, a rapid increase of the time-average scattered intensity, 〈I〉T, and a steep decrease of the initial amplitude of the intensity-intensity time correlation function, , were observed at the gelation threshold. On the other hand, P-jump showed a gradual increase of the 〈I〉T and a continuous decrease of the . It was revealed by SANS that bLG underwent thermal denaturation, resulting in a formation of gels consisting of densely aggregated unfolded bLG oligomers. On the other hand, the pressure-induced gels were found to be a fractal aggregates consisting of primary particles of bLG monomers. The difference in the gel structure as well as gelation mechanism between bLGs treated by T-jump and P-jump is discussed in comparison with T-induced and P-induced microphase separation of amphiphilic block copolymers in water [Osaka N, Shibayama M. Phys Rev Lett 2006;96:048303]. 相似文献
165.
Ninshu Ma Atsushi Kunugi Tei Hirashima Katsumi Okubo Mitsuhiro Kamioka 《Welding International》2013,27(1):9-14
Friction spot welding (FSJ) process is very complicated in the aspects of material flow, heat generation and joining mechanism. Compared with the friction stir welding (FSW) process for a butt joint, the FSJ process is used to join two pieces of plate in the direction of thickness. Although there are several papers describing simulation models for the FSW process, we cannot find any papers relating to simulation models for the FSJ process. In order to simulate the FSJ process efficiently, an axis-symmetric two-dimensional FEM model with an adaptive re-meshing algorithm is proposed. By using the proposed model, temperature distribution, joining shape of the transverse section including toe flash on the surface and hook on the joining interface, can be simulated. The simulated results agree well with those of the experiment. Furthermore, effects of clamp position and stirring direction on material flow and joining shape are investigated. 相似文献
166.
Masashi Uchida Mitsuhiro Kanazawa Atsushi Ogiwara Hiroshi Sezaki Akihiro Ando Yohei Miyamoto 《International journal of molecular sciences》2013,14(10):19716-19730
The identification of metabolites in drug discovery is important. At present, radioisotopes and mass spectrometry are both widely used. However, rapid and comprehensive identification is still laborious and difficult. In this study, we developed new analytical software and employed a stable isotope as a tool to identify drug metabolites using mass spectrometry. A deuterium-labeled compound and non-labeled compound were both metabolized in human liver microsomes and analyzed by liquid chromatography/time-of-flight mass spectrometry (LC-TOF-MS). We computationally aligned two different MS data sets and filtered ions having a specific mass-shift equal to masses of labeled isotopes between those data using our own software. For pioglitazone and flurbiprofen, eight and four metabolites, respectively, were identified with calculations of mass and formulas and chemical structural fragmentation analysis. With high resolution MS, the approach became more accurate. The approach detected two unexpected metabolites in pioglitazone, i.e., the hydroxypropanamide form and the aldehyde hydrolysis form, which other approaches such as metabolite-biotransformation list matching and mass defect filtering could not detect. We demonstrated that the approach using computational alignment and stable isotopic mass-shift filtering has the ability to identify drug metabolites and is useful in drug discovery. 相似文献
167.
Naoyuki Hoshiya Satoshi Shuto Mitsuhiro Arisawa 《Advanced Synthesis \u0026amp; Catalysis》2011,353(5):743-748
The actual active species of the recently developed sulfur‐modified, gold‐supported palladium material, S ‐modified A u‐supported Pd (SAPd), with one of the lowest Pd‐releasing levels and high recyclability in the Suzuki–Miyaura coupling, was investigated. Also, SAPd was found to work repeatedly as an excellent Pd reservoir for liquid‐phase combinatorial synthesis. 相似文献
168.
A mixture of acrylated castor oil (ACO) with N‐carbobenzyloxy‐L ‐isoleucylaminooctadecane (CIA) or (R)‐12‐hydroxystrearic acid (HSA) containing photo‐initiators was heated to 130°C and gradually cooled to room temperature to give bio‐based gelatinous material. The photo‐curing of the gel generated a crosslinked ACO composite containing CIA or HSA. The optical micrographic and differential scanning calorimetry analyses revealed that a supramolecular fibrous network is formed for photo‐cured ACO (cACO)/CIA and that spherulitic crystals are formed for cACO/HSA. The tan δ peak temperatures measured by dynamic mechanical analysis for cACO/CIA and cACO/HSA composites were higher than that of cACO. The flexural strength and modulus of cACO/CIA composites increased with an increase of CIA content, and those values were higher than those of cACO/HSA composites. POLYM. COMPOS., 33:2001–2008, 2012. © 2012 Society of Plastics Engineers 相似文献
169.
After a bio‐based epoxy resin, sorbitol polyglycidyl ether (SPE) was mixed with a flavonoid, quercetin (QC) in tetrahydrofuran at an optimized epoxy/hydroxy ratio 1/1.2, the obtained SPE/QC solution was mixed with wood flour (WF), prepolymerized at 150°C, and subsequently compressed at 170°C for 3 h to give SPE‐QC/WF biocomposites (WF content:0, 20, 30, 40 wt %). The tan δ peak temperature of SPE‐QC without WF (85.5°C) was higher than that of SPE cured with conventional phenol novolac (81.0°C). In addition, diglycidyl ether of bisphenol A cured with QC had a higher tan δ peak temperature (145.1°C) than that cured with PN (90.8°C). The tan δ peak temperatures (106–113°C) of SPE‐QC/WF biocomposites were significantly higher than that of SPE‐QC. The tensile modulus of SPE‐QC/WF biocomposites increased with increasing WF content. A lower wavenumber shift of carbonyl stretching absorption peak in the FTIR spectrum of SPE‐QC/WF as compared with that of SPE‐QC suggested that hydroxy group of woody component forms hydrogen bonding with carbonyl group of quercetin moiety. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
170.
Mitsuhiro Shibata Naozumi Teramoto Kyohei Hoshino Hayato Takase Ayaka Shibita 《应用聚合物科学杂志》2013,130(6):4229-4236
Semi‐interpenetrating polymer networks (S‐IPNs) were prepared by the reactions of hydroxyl‐terminated four‐armed, star‐shaped ε‐caprolactone oligomers with degrees of polymerization per one oligocaprolactone chain (ns) of 3, 5, and 10 and 2,4‐tolylene diisocyanate (TDI) in the presence of poly(ε‐caprolactone) (PCL). In the dynamic mechanical analysis of the S‐IPN [2,4‐tolylene diisocyanate bridged hydroxyl‐terminated four‐armed, star‐shaped ε‐caprolactone oligomer (TH4CLO)/PCL], only one tan δ peak was observed; its temperature increased with increasing TH4CLO content and with decreasing n value. Differential scanning calorimetric analyses of the TH4CLOs and TH4CLO/PCLs revealed that the TH4CLOs with ns of 3 and 5 were amorphous, whereas TH4CLO with an n of 10 was semicrystalline and that the crystallization of the PCL chain for TH4CLO/PCLs was more strongly disturbed with increasing TH4CLO content and decreasing n value. Although the tensile strength, modulus, and elongation at break of TH4CLO were much lower than those of PCL, those values increased with the n value. Although the tensile strength and modulus of the TH4CLO/PCLs decreased with increasing TH4CLO content, TH4CLO (n = 3)/PCL 50/50 showed the highest elongation at break (314%) among the S‐IPNs because of the suppression of crystallization of the polycaprolactone chain. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4229–4236, 2013 相似文献