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231.
232.
Gilles Goulet Jean Amiot Clovis Simard Jocelyne Delisle Germain J. Brisson 《Journal of the science of food and agriculture》1985,36(4):305-310
The nutritive value of zein, rapeseed 12S and α-casein was assessed by apparent digestibility coefficient (ADC) and net protein ratio (NPR). Protein fractions were suspended (100 g litre?1) in 0.1M HCl or in water and autoclaved for 1 h. The degree of deamidisation following acid autoclaving was 14.0% for zein, 7.3% for rapeseed 12S and 8.9% for α-casein. Results indicate that autoclaving in water or in HCl improved the ADC of zein and rapeseed 12S. However, acid autoclaving increased (P<0.05) the NPR of rapeseed 12S (from 3.07 to 3.44) whereas it decreased (P<0.05) that of α-casein (from 4.21 to 3.57). 相似文献
233.
From the partial study of the systems “BaOTiO2A2Ti6O13” three series of non-stoichiometric titanates A2?2xBa3xTi6?xO13 were isolated for A = Na, K, Rb with x ranging from 0 to about 0.2. The structural evolution of these oxides, which are isostructural of Na2Ti6O13 (1) was studied and discussed. 相似文献
234.
Büttner MW Burschka C Daiss JO Ivanova D Rochel N Kammerer S Peluso-Iltis C Bindler A Gaudon C Germain P Moras D Gronemeyer H Tacke R 《Chembiochem : a European journal of chemical biology》2007,8(14):1688-1699
Twofold sila-substitution (C/Si exchange) in the saturated ring of the tetrahydronaphthalene skeleton of the retinoid agonists TTNPB (1 a) and 3-methyl-TTNPB (2 a) leads to disila-TTNPB (1 b) and disila-3-methyl-TTNPB (2 b), respectively. The silicon compounds 1 b and 2 b were synthesized in multiple steps, and their identities were established by elemental analyses, multinuclear NMR experiments, and single-crystal X-ray diffraction studies. Like TTNPB (1 a) and 3-methyl-TTNPB (2 a), the analogous silicon-based arotinoids 1 b and 2 b are strong pan-RAR agonists and display the same strong differentiation and apoptosis-inducing activity in NB4 promyelocytic leukemia cells as the parent carbon compounds. These results are in keeping with the nearly isomorphous structures of 1 a and 1 b bound to the complex of the RARbeta ligand-binding domain with the nuclear receptor (NR) box 2 peptide of the SRC-1 coactivator. The contacts within the ligand-binding pocket are identical except for helix H11, for which two turns are shifted in the disila-TTNPB (1 b) complex. This study represents the first comprehensive structure-function analysis of a carbon/silicon switch in a signaling molecule and demonstrates that silicon analogues can have the same biological functionalities and conserved structures as their parent carbon compounds, and it illustrates at the same time that silicon analogues of biologically active compounds have the potential to induce alternative allosteric effects, as in the case of helix H11, which might allow for novel options in drug design. 相似文献
235.
Kai Cheng M. Leys S. Degroote B. Van Daele S. Boeykens J. Derluyn M. Germain G. Van Tendeloo J. Engelen G. Borghs 《Journal of Electronic Materials》2006,35(4):592-598
In this work, we report on the growth by metalorganic vapor phase epitaxy (MOVPE) of GaN layers on AlN/Si(111) templates with
step-graded AlGaN intermediate layers. First, we will discuss the optimization of the AlN/Si(111) templates and then we will
discuss the incorporation of step-graded AlGaN intermediate layers. It is found that the growth stress in GaN on high-temperature
(HT) AlN/Si(111) templates is compressive, although, due to relaxation, the stress we have measured is much lower than the
theoretical value. In order to prevent the stress relaxation, step-graded AlGaN layers are introduced and a crack-free GaN
epitaxial layer of thickness >1 μm is demonstrated. Under optimized growth conditions, the total layer stack, exceeding 2
μm in total, is kept under compressive stress, and the radius of the convex wafer bowing is as large as 119 m. The crystalline
quality of the GaN layers is examined by high-resolution x-ray diffraction (HR-XRD), and the full-width-at-half maximums (FWHMs)
of the x-ray rocking curve (0002) ω-scan and (−1015) ω-scan are 790 arc sec and 730 arc sec, respectively. It is found by
cross-sectional transmission electron microscopy (TEM) that the step-graded AlGaN layers terminate or bend the dislocations
at the interfaces. 相似文献
236.
Christianne Mulat Marc Donias Pierre Baylou Gérard Vignoles Christian Germain 《Signal, Image and Video Processing》2008,2(1):51-58
This paper introduces low-level operators in the context of detecting cylindrical axis in 3D images. Knowing the axis of a
cylinder is particularly useful since its location, length and curvature derive from this knowledge. This paper introduces
a new gradient-based optimal operator dedicated to accurate estimation of the direction toward the axis. The operator relies
on Finite Impulse Response filters. The approach is presented first in a 2D context, thus providing optimal gradient masks
for locating the center of circular objects. Then, a 3D extension is provided, allowing the exact estimation of the orientation
toward the axis of cylindrical objects when this axis coincides with one of the mask reference axes. Applied to more general
cylinders and to noisy data, the operator still provides accurate estimation and outperforms classical gradient operators. 相似文献
237.
Y. Guhel B. Boudart E. Delos M. Germain Z. Bougrioua 《Microelectronics Reliability》2006,46(5-6):786-793
Schottky contacts of Pt and Ir on undoped Al0.36Ga0.64N have been fabricated and the ideality factor, the built-in voltage and the reverse bias current were determined using current–voltage measurements to make a comparison.The smallest ideality factors, the lowest reverse bias current and the highest built-in voltages have been obtained for Ir Schottky contacts.We have studied the effect of an annealing for Pt and Ir Schottky contacts, on the ideality factor, the built-in voltage and the reverse bias current. A decrease of the ideality factor and the reverse bias current associated to an increase of the built-in voltage have been obtained except for high annealing temperature (T > 400 °C).Reductions of 37% and 43% of the ideality factor and improvements of 24% and 41% of the built-in voltage have been obtained for Pt and Ir Schottky contacts, respectively, after an annealing performed at 350 °C during 30 min.Two different electrical stresses have also been applied on the ohmic and Schottky contacts during 164 h to study the reliability of the employed technology. In a first time, the devices have been stressed with a drain-to-source voltage VDS of 20 V and a gate-to-source voltage VGS of −5 V to submit the devices to an electrical field only and not to a thermal effect induced by the electrical current. In a second time, the aging stress has been applied for a VDS of 20 V and for a VGS of 0 V in order to study the impact of the electrical field and the thermal effect induced by the drain current on the electrical behaviours of Al0.36Ga0.64N/GaN transistors. This study has also shown the existence of electrical traps in the device structure and proved the good reliability of the involved technology.These comparative studies demonstrate that Ir is a better candidate than Pt for the realisation of Schottky contacts on undoped Al0.36Ga0.64N. 相似文献
238.
Radiometric measurements of the microwave emissivity of foam 总被引:3,自引:0,他引:3
Rose L.A. Asher W.E. Reising S.C. Gaiser P.W. St Germain K.M. Dowgiallo D.J. Horgan K.A. Farquharson G. Knapp E.J. 《Geoscience and Remote Sensing, IEEE Transactions on》2002,40(12):2619-2625
Radiometric measurements of the microwave emissivity of foam were conducted during May 2000 at the Naval Research Laboratory's Chesapeake Bay Detachment using radiometers operating at 10.8 and 36.5 GHz. Horizontal and vertical polarization measurements were performed at 36.5 GHz; horizontal, vertical, +45/spl deg/, -45/spl deg/, left-circular, and right-circular polarization measurements were obtained at 10.8 GHz. These measurements were carried out over a range of incidence angles from 30/spl deg/ to 60/spl deg/. Surface foam was generated by blowing compressed air through a matrix of gas-permeable tubing supported by an aluminum frame and floats. Video micrographs of the foam were used to measure bubble size distribution and foam layer thickness. A video camera was boresighted with the radiometers to determine the beam-fill fraction of the foam generator. Results show emissivities that were greater than 0.9 and approximately constant in value over the range of incidence angles for vertically polarized radiation at both 10.8 and 36.5 GHz, while emissivities of horizontally polarized radiation showed a gradual decrease in value as incidence angle increased. Emissivities at +45/spl deg/, -45/spl deg/, left-circular, and right-circular polarizations were all very nearly equal to each other and were in turn approximately equal to the average values of the horizontal and vertical emissivities in each case. 相似文献
239.
Matj Hla Shohei Fujii Alex Redinger Yukari Inoue Germain Rey Maxime Thevenin Valrie Deprdurand Thomas Paul Weiss Tobias Bertram Susanne Siebentritt 《Progress in Photovoltaics: Research and Applications》2015,23(11):1630-1641
We present an approach for deposition of highly conductive nominally undoped ZnO films that are suitable for the n‐type window of low band gap solar cells. We demonstrate that low‐voltage radio frequency (RF) biasing of growing ZnO films during their deposition by non‐reactive sputtering makes them as conductive as when doped by aluminium (ρ≤1·10−3Ω cm). The films prepared with additional RF biasing possess lower free‐carrier concentration and higher free‐carrier mobility than Al‐doped ZnO (AZO) films of the same resistivity, which results in a substantially higher transparency in the near infrared region (NIR). Furthermore, these films exhibit good ambient stability and lower high‐temperature stability than the AZO films of the same thickness. We also present the characteristics of Cu(InGa)Se2, CuInSe2 and Cu2ZnSnSe4‐based solar cells prepared with the transparent window bilayer formed of the isolating and conductive ZnO films and compare them to their counterparts with a standard ZnO/AZO bilayer. We show that the solar cells with nominally undoped ZnO as their transparent conductive oxide layer exhibit an improved quantum efficiency for λ > 900 nm, which leads to a higher short circuit current density JSC. This aspect is specifically beneficial in preparation of the Cu2ZnSnSe4 solar cells with band gap down to 0.85 eV; our champion device reached a JSC of nearly 39 mAcm−2, an open circuit voltage of 378mV, and a power conversion efficiency of 8.4 %. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
240.
Venkata Narasimha Manyam Dang-Kièn Germain Pham Chadi Jabbour Patricia Desgreys 《Analog Integrated Circuits and Signal Processing》2018,97(3):483-492
In this paper, we present a low-power high-performance digital predistorter (DPD) for the linearization of wideband RF power amplifiers (PAs). It is based on the novel FIR memory polynomial (FIR-MP) predistorter model, which significantly augments the performance of the conventional memory polynomial predistorter with the use of complex baseband digital FIR filter prior to the memory polynomial. The adjacent channel leakage ratio (ACLR) performance comparison between the conventional MP and the proposed FIR-MP is done based on simulations with multi-carrier modulated signals of 20 and 80 MHz bandwidths. The PA models used for the simulations are extracted from the measurements of a commercial \(1\,\hbox {W}\) GaAs HBT PA. At the ideal system-level simulations, the improvements in ACLR over the conventional MP are 7.2 and 15.6 dB, respectively, for 20 and 80 MHz signals. The choice of selection of various parameters of the predistorter along with the subsequent digital-to-analog converter (DAC) is presented. The impact of fixed-point representation is assessed using ACLR metrics, which shows that a wordlength of 14 bits is sufficient to obtain ACLR beyond \(45\,\hbox {dBc}\) with a margin of \(10\,\hbox {dB}\). The proposed predistorter is synthesized in \(28\,\hbox {nm}\) fully-depleted silicon-on-insulator (FDSOI) CMOS process. It is shown that with a fraction of the power and die area of that of the MP a huge improvement in ACLR is attained. With an overall power consumption of 8.2 and 88.8 mW, respectively, for 20 and 80 MHz signals, the FIR-MP DPD proves to be a suitable candidate for small-cell base station PA linearization. 相似文献