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71.
BACKGROUND: Effects of the plant growth‐promoting rhizobacteria (PGPR) strains Burkholderia gladii BA‐7, Bacillus subtilis OSU‐142, Bacillus megatorium M‐3 and Azospirillum brasilense Sp 245 on vegetative development and mineral uptake of 1103 P and 41 B grapevine rootstocks were investigated. The roots of nursery plants of the grapevine rootstocks were immersed in bacterial solutions and transplanted to a sterilised peat and perlite mixture in 5 L pots. Plants were cultivated in a semi‐controlled glasshouse during the vegetation period. RESULTS: Vegetative development of grapevine rootstocks was obviously promoted by bacterial inoculation, with the maximum increase induced by Sp 245. Inoculation with Sp 245 also significantly improved the chlorophyll concentrations of the leaves of the two rootstocks. Among the bacteria, OSU‐142 also significantly stimulated vegetative development and mineral acquisition of the plants. Nutrient contents of the leaf blades of the plants were generally higher than those of control plants. CONCLUSION: Overall investigations revealed that A. brasilense Sp 245 and B. subtilis OSU‐142 performed more efficiently than the other strains. Therefore these bacteria seem to have considerable potential in reducing the need for inorganic fertiliser. Copyright © 2012 Society of Chemical Industry  相似文献   
72.
Heat transport subject to nonlinear thermal radiation has multiple applications in physics, industry, engineering field, and space technology, such as aerodynamic rockets, solar power technology, large open water reservoirs, and gas-cooled nuclear reactors. This effort studies the magnetohydrodynamic flow of cross fluid, which is a type of non-Newtonian, along a heated surface. Furthermore, the transportation of heat in the fluid is induced by  thermal radiation. Furthermore, the behavior of opposing/assisting flow and impact of nonuniform heat sink/source is scrutinized. The reserved suitable transformations are carried out to shift the ruling equations into nondimensional class. Through reserved transformations, two nonlinear partial differential equations are altered into corresponding nonlinear ordinary differential equations. Then a scheme of integration referred to as Runge–Kutta–Fehlberg is imposed to get a numerical solution of these. The impact of parameters are mentioned concisely on temperature and velocity profiles in the absence and presence of a magnetic parameter. It is proved that the presence of a magnetic field steps up the velocity and temperature as well.  相似文献   
73.
This article focuses on the three-dimensional Cross fluid flow of a radiative nanofluid over an expanding sheet with aligned magnetic field, chemical reaction, and heat generation phenomenon. The stretching sheet has convective heat and slip boundary conditions. The similarity variables are properly used for the conversion of a dimensional mathematical model into a nondimensional one. The transformed ordinary differential equations are handled for the numerical outcomes of the suggested fluidic model by incorporating the shooting scheme. Furthermore, the numeric investigations are also compared by bvp4c MATLAB built-in package. In a limited case, both the techniques are checked with already published articles, thereby revealing good agreement. Furthermore, the effects of few parameters like Prandtl number, Weissenberg number, heat generation, stretching rate parameter, magnetic parameter, thermal radiation, Brownian and thermophoresis parameters, and Lewis number on concentration, temperature, and velocity profiles have been presented using figures and numerical tables. The strong intensity of the magnetic field across the fluid and increment in the inclination angle (ϑ) result in a lower velocity profile. Temperature is more prominent for the higher slip mechanism. Furthermore, there in an increase in thermophoretic force, which pushes the nanoparticles, and this mixing of nanoparticles helps to increase the concentration profile. A higher Cross fluid index responds to a larger velocity.  相似文献   
74.
Here, modeling and computations are performed to explore the impact of variable molecular diffusivity, nonlinear thermal radiation, convective boundary conditions, momentum slip, and variable molecular diffusivity on Prandtl fluid past a stretching sheet. By using the compatible transformation, the partial differential equations regarding momentum, energy, and concentration are reformed into ordinary differential equations and furthermore, these equations are handled numerically via the shooting method. The behavior of intricate parameters that emerge during numerical simulation is displayed in the form of tables and graphs. These outcomes are supplemented with the information for the heat transfer rate and surface drag coefficients. It is perceived that an uplift in the temperature profile occurs by virtue of augmentation in the temperature convection parameter, and furthermore, mass fraction field escalates owing to an amplification in the chemical reaction coefficient.  相似文献   
75.
Key developments in the field of nanotechnology have drawn the attention of many scholars toward the interaction of nanoparticles due to their capturing applications in solar energy systems and thermal engineering. Larger consumption of energy posed a challenge for thermal science, so thermal engineering is trying to solve this issue by increasing the thermal conductivity of the fluid. The thermal conductivity of conventional fluid is increased by incorporating the nanoparticles in the base fluid. Keeping this in mind, the present research project addresses the utilization of nanoparticles in a steady three-dimensional rotating flow of magnetohydrodynamic water-based hybrid fluid over an extending sheet. Nanoparticles of aluminum oxide (Al2O3) and silver (Ag) are being used with water (H2O) as base fluid. The velocity of nanoparticles is being captured under the influence of an inclined magnetic field and the transport of heat is scrutinized through thermal radiation. The physical model generates partial differential equations and then transported into an equivalent set of a nonlinear ordinary differential equations. The purpose of numerical computation is made by the Lobatto IIIA method, which is a type of Matlab scheme bvp4c and based on the finite difference method. Geometry of velocity profile is explained with different parameters in presence and absence of magnetic field and energy of hybrid nanofluid is explained under the influence of the inclined and perpendicular magnetic field. Gradual increment in ϑ both f and g profiles because strengthen the magnetic field results lower velocity. An increment in nanoparticle concentration of Al2O3 and Ag gives a larger magnitude of velocity. The rotation parameter shows the rotation of nanoparticles; due to these rotations both linear and angular components of velocity increase in the presence and absence of a magnetic effect.  相似文献   
76.
A design method is described for a saturistor which enables the stall current of an induction motor to be restricted to some predetermined value without significant effect on the full-load operation. The design method requires knowledge of the dynamic B?H loop for the hard magnetic saturistor material. With controlled sinusoidal primary supply voltage and the saturistor connected in the secondary circuit, increased torque at reduced current was obtained during stall.  相似文献   
77.
Refined olive oil was enriched with palmitic acid (PA) and docosahexaenoic acid (DHA) via lipase-catalyzed acidolysis reaction using Novozym 435 in hexane. The enrichment reaction was optimized by response surface methodology. Three independent variables, reaction time (12, 18, and 24 h), temperature (55, 60, and 65 °C), and substrate molar ratio (refined olive oil:DHA single cell oil free fatty acid:PA 1:1:6, 1:1:9, and 1:1:12) and three responses, total PA and DHA incorporation, and PA content at the sn-2 position were investigated. Results showed that PA was incorporated into the triacylglycerols(TAGs) of refined olive oil at up to 55.79 mol % while incorporation of PA at the sn-2 position and total DHA were found to be up to 33.63 and 3.54 mol %, respectively. Second-order models were generated for each of the three responses. A Chi-square test verified that the predicted values from the models were not significantly different from the observed ones. The prediction power of the models was further confirmed by a solvent-free scale-up reaction. The produced structured lipids have the potential to be used in infant formula.  相似文献   
78.
Colloidal particles with fluorescence read‐out are commonly used as sensors for the quantitative determination of ions. Calcium, for example, is a biologically highly relevant ion in signaling, and thus knowledge of its spatio‐temporal distribution inside cells would offer important experimental data. However, the use of particle‐based intracellular sensors for ion detection is not straightforward. Important associated problems involve delivery and intracellular location of particle‐based fluorophores, crosstalk of the fluorescence read‐out with pH, and spectral overlap of the emission spectra of different fluorophores. These potential problems are outlined and discussed here with selected experimental examples. Potential solutions are discussed and form a guideline for particle‐based intracellular imaging of ions.  相似文献   
79.
Guest editorial     
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80.
Magneto peristaltic flows of nanofluids play a key role in magnetic drug transport systems. Therefore, peristalsis of a nanofluid through a uniform porous medium under the influence of a uniform magnetic force is studied here. Ohmic heating and Hall aspects are incorporated in the analysis. Three distinct types of nanoparticles (ie, silver, alumina, and copper) have been used for theoretical analysis. A large wavelength and a small Reynolds number scheme are adopted in mathematical modeling. The dimensionless nonlinear system is solved using the well‐known perturbation method, and physical analysis is done via graphs. A comparison of different nanoparticles is also presented. It is noticed that an increase in the Hall effects nullifies the variations, which are due to an increment in the Hartman number. The temperature of the nanofluid can be reduced by increasing the permeability of the porous medium.  相似文献   
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