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61.
Shahbaz Areej Hussain Nazim Intisar Azeem Bilal Muhammad Iqbal Hafiz M. N. 《Catalysis Letters》2022,152(9):2637-2649
Catalysis Letters - The versatility of immobilized enzyme systems enables rapid recovery of both product and enzyme, numerous re-uses of enzymes, continuous enzymatic processes, quick reaction... 相似文献
62.
In the present study, an attempt is made to enhance the performance of heat pump by utilizing two types of nanofluids namely, copper and alumina nanofluids. These nanofluids were employed around the evaporator coil of the heat pump. The nanofluids were used to enhance the heat input to the system by means of providing an external jacket around the evaporator coil. Both the nanofluids were prepared in three volume fractions 1%, 2% and 5%. Water was chosen as the base fluid. The performance of the heat pump was assessed by calculating the coefficient of performance of the system when it was operated with and without nanofluid jacket. A significant enhancement in the coefficient of performance was noticed when copper and alumina nanofluids were employed in the system. Also, the coefficient of performance was found to have a direct relationship with the tested volume fractions. For the highest volume fraction of 5%, the performance of the heat pump was found to enhance by 23% with alumina nanofluid, while for copper nanofluid, a very significant enhancement in performance by 72% was observed. Thus, utilizing of nanofluids in heat pumps can be very beneficial towards performance enhancement and the idea can also be extended to other thermal systems such as steam power plant, automobile radiator, industrial heat exchangers and refrigeration systems. 相似文献
63.
Designing Fast Fourier Transform Accelerators for Orthogonal Frequency-Division Multiplexing Systems
Waqar Hussain Fabio Garzia Tapani Ahonen Jari Nurmi 《Journal of Signal Processing Systems》2012,69(2):161-171
Designing accelerators for the real-time computation of Fast Fourier Transform (FFT) algorithms for state-of-the-art Orthogonal Frequency-Division Multiplexing (OFDM) demodulators has always been challenging. We have scaled-up a template-based Coarse-Grain Reconfigurable Array device for faster FFT processing that generates special purpose accelerators based on the user input. Using a basic and a scaled-up version, we have generated a radix-4 and mixed-radix (2, 4) FFT accelerator to process different length and types of algorithms. Our implementation results show that these accelerators satisfy not only the execution time requirements of FFT processing for Single Input Single Output (SISO) wireless standards that are IEEE-802.11 a/g and 3GPP-LTE but also for Multiple Input Multiple Output (MIMO) IEEE-802.11n standard. 相似文献
64.
Atif Kamil Mubarak Ali Khan Muhammad AAsim Nadir Zaman Khan Raham Sher Khan Muhsin Jamal Waqar Ahmad Mir Azam Khan Fazal Jalil 《Biocell》2019,43(3):167-174
Several toxic compounds are known to induce apoptosis in mammalian cell lines. The human neuroblastoma
cells (SH-SY5Y) were exposed to the phosphatase inhibiting toxin okadaic acid (OA) or hydrogen peroxide (H2O2)
to induce apoptosis as well as generate reactive oxygen species (ROS). Mitoxantrone (MXT) was used as a positive
control for apoptosis. The SH-SY5Y cells were transfected with eukaryotic expression plasmid pHyPer-dMito encoding
mitochondrial-targeted fluorescent or pHyPer-dCito encoding cytoplasmic-targeted fluorescent sensor for hydrogen
peroxide (HyPer). The ERp57, also called GRP58 (Glucose-regulated protein 58), is a stress protein induced in
conditions like glucose starvation and viral infection. Recently ERp57 was shown to translocate from the endoplasmatic
reticulum to the cell surface in anthracycline-induced apoptotic cells. ERp57 co-translocation together with calreticulin
has been suggested to be crucial for recognizing tumor cells to induce immunogenic cell death. ERp57 translocation
after exposure to okadaic acid was studied using immunofluorescence and confocal microscopy. These studies indicated
that okadaic acid has induced the translocation of ERp57 to the cellular membrane. 相似文献
65.
66.
ABSTRACT Interpolation approximation for an entire B/H curve range can be obtained by a simple spline algorithm. This paper describes a simplified technique to employ a spline algorithm to approximate interpolated values. This technique minimizes time for computer applications, and is suitable for computer aided design of electromagnetic devices where the complete B/H curve is required to be read from a finite number of given points 相似文献
67.
The paper presents an entropy generation analysis for steady conduction in a slab with temperature‐dependent volumetric internal heat generation. The slab experiences asymmetric convective cooling on its two faces. The exact analytical solution for the temperature distribution is used to compute dimensionless local and total entropy generation rates in the slab. The total entropy generation rate depends on five dimensionless parameters: reference heat generation temperature Q, the heat generation–temperature variation parameter a, the temperature asymmetry parameter λ, and Biot numbers Bi1 and Bi2. Graphs illustrating the effect of these five parameters on the local and total entropy generation rates are presented and discussed. It is found that the total entropy generation in the slab can be minimized with a suitable choice of the cooling parameters. The paper corrects the flawed entropy results published recently. The present results for the special case of uniform internal heat generation confirm the results presented in a 2003 paper. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.20404 相似文献
68.
Sumon Saha Ahmed Kadhim Hussein Waqar Ahmed Khan H.A. Mohammed Watit Pakdee Arman Hasanpour 《亚洲传热研究》2012,41(5):388-401
A numerical analysis is carried out to study the performance of natural convection inside a square open tilted cavity filled with air. An adiabatic circular solid cylinder is placed at the center of the cavity and the sidewall in front of the breathing space is heated by a constant heat flux. The top and bottom walls are kept at the ambient constant temperature. Two‐dimensional forms of Navier–Stokes equations along with the energy equations are solved using the Galerkin finite element method. Results are obtained for a range of Grashof numbers from 103 to 106 at Pr = 0.71 while the tilt angle varies from 0 to 45° and the diameter ratio of the cylinder is considered to be 0.2, 0.3, and 0.4 with constant physical properties. The parametric studies for a wide range of cylinder diameter ratios and cavity tilt angles show significant features of the present problem in terms of stream functions and temperature profiles. The computational results indicate that the heat transfer coefficient is strongly influenced by the above governing parameters. It is also found that the average Nusselt number decreases when the diameter ratio increases. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.21001 相似文献
69.
English A Azeem A Gaspar DA Keane K Kumar P Keeney M Rooney N Pandit A Zeugolis DI 《Journal of materials science. Materials in medicine》2012,23(1):137-148
Anisotropic alignment of collagen fibres in musculoskeletal tissues is responsible for the resistance to mechanical loading,
whilst in cornea is responsible for transparency. Herein, we evaluated the response of tenocytes, osteoblasts and corneal
fibroblasts to the topographies created through electro-spinning and solvent casting. We also evaluated the influence of topography
on mechanical properties. At day 14, human osteoblasts seeded on aligned orientated electro-spun mats exhibited the lowest
metabolic activity (P < 0.001). At day 5 and at day 7, no significant difference was observed in metabolic activity of human corneal fibroblasts
and bovine tenocytes respectively seeded on different scaffold conformations (P > 0.05). Osteoblasts and corneal fibroblasts aligned parallel to the direction of the aligned orientated electro-spun mats,
whilst tenocytes aligned perpendicular to the aligned orientated electro-spun mats. Mechanical evaluation demonstrated that
aligned orientated electro-spun fibres exhibited significant higher stress at break values than their random aligned counterparts
(P < 0.006) and random orientated electro-spun fibres exhibited significant higher strain at break values than the aligned orientated
scaffolds (P < 0.006). While maintaining fibre structure, we also developed a co-deposition method of spraying and electro-spinning, which
enables the incorporation of microspheres within the three-dimensional structure of the scaffold. 相似文献
70.
This paper shows that the set of rational, strictly proper, robustly stabilizing controllers for single‐input single‐output linear‐time invariant plants will form a bounded (can even be empty) set in the controller parameter space if and only if the order of the stabilizing controller cannot be reduced any further; if the set of proper stabilizing controllers of order r is not empty and the set of strictly proper controllers of order r is bounded, then r is the minimal order of stabilization. The paper also extends this result to characterize the set of controllers that guarantee some pre‐specified performance specifications. In particular, it is shown here that the minimal order of a controller that guarantees specified performance is l iff (1) there is a controller of order l guaranteeing the specified performance and (2) the set of strictly proper, robustly stabilizing controllers of order l and guaranteeing the performance is bounded. Moreover, if the order of the controller is increased, the set of higher‐order controllers which satisfies the specified performance will necessarily be unbounded. This characterization is provided for performance specifications, such as gain margin and robust stability, which require a one‐parameter family of real polynomials to be Hurwitz, where the parameter is in a closed interval. Other performance specifications, such as phase margin and ℋ︁∞ norm, can be reduced to the problem of determining a set of stabilizing controllers that renders a family of complex polynomials Hurwitz. The characterization of the set of controllers for the stabilization of complex polynomials is provided and is used to show the boundedness properties for the set of controllers that guarantee a given phase margin or an upper bound on the ℋ︁∞ norm. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献