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The present work has been carried out in order to design a new type of ultrasonic reactor consisting of a double-structured tank. The inner working compartment is built with a slant bottom to allow a better ultrasonic transmission. This paper reports the effect of the inclination angle on acoustic efficiency for several different plates, e.g. two plates made of glass (2 mm and 3 mm thickness) and one made of PVC (3 mm thickness). The acoustic efficiency was determined as the ratio of the signal measured by a hydrophone in the presence of the plate to that signal in the absence of the plate. Having optimised the system, the ultrasonic powers in the inner and the outer compartments of the slant bottom reactor were determined by hydrogen peroxide dosimetry.  相似文献   
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Phenomenological equations are deduced which give the flows of matter, volume, charge and heat for a discontinuous system in which inertial terms in the viscous equations of motion are not negligible. It is found that the equations contain terms in the powers of the first-order affinities, with corresponding phenomenological coefficients. These coefficients can all be derived from first-order coefficients, however, and thus refer to a system which is close to equilibrium. The theory agrees with well-documented specific hydrodynamic calculations, but generalizes these in the framework of now equilibrium thermodynamics.  相似文献   
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The effect of ultrasound upon the destruction of micro-organisms has been studied and reported here. The results obtained from the work carried out has shown that ultrasound can be used effectively for water disinfection and has several advantages. When used in conjunction with chlorine it significantly reduces the number of bacteria present in water samples. Ultrasound also reduces the amount of chlorine required for disinfection. Increasing the power of ultrasound leads to greater efficiency in the destruction of bacterial cells. High frequency ultrasound is more beneficial than low frequency in the disinfection of water.  相似文献   
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Park  Joseph  Pao  Gerald M.  Sugihara  George  Stabenau  Erik  Lorimer  Thomas 《Nonlinear dynamics》2022,108(3):2147-2160

Data-driven, model-free analytics are natural choices for discovery and forecasting of complex, nonlinear systems. Methods that operate in the system state-space require either an explicit multidimensional state-space, or, one approximated from available observations. Since observational data are frequently sampled with noise, it is possible that noise can corrupt the state-space representation degrading analytical performance. Here, we evaluate the synthesis of empirical mode decomposition with empirical dynamic modeling, which we term empirical mode modeling, to increase the information content of state-space representations in the presence of noise. Evaluation of a mathematical, and, an ecologically important geophysical application across three different state-space representations suggests that empirical mode modeling may be a useful technique for data-driven, model-free, state-space analysis in the presence of noise.

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Potential uses of ultrasound in the biological decontamination of water   总被引:10,自引:0,他引:10  
In the past there was a prevailing feeling in industry that power ultrasound would be too expensive to use for water treatment on an industrial scale. This was based on calculations involving the direct scale up of power consumption in small-scale (generally batch) laboratory experiments. In recent times this attitude has changed somewhat as a result of the installation of a number of ultrasonic devices in operational water or sewage treatment plants. In our laboratories we have investigated the decontamination of water under the influence of ultrasound alone and in conjunction with other treatments. The results, particularly when applied to flowing systems, indicate a real future for sonochemistry in water treatment.  相似文献   
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An old question regarding the world we live in concerns what is real regarding points and lines: if two distinct lines intersect, is their intersection a unique point? In this paper, we take the approach that the answer is no, that all the points in the intersection are somehow close to one another (neighbourly) and that two non-neighbourly points determine a unique line. These are the Affine Klingenberg spaces (AK-spaces). How does one put a logical structure on points and lines that reflect the preceding view of reality? History has shown that such a structure is based upon the concept of coordinatization, which leads naturally to algebraic structures that allow a faithful representation of incidence, which in turn reflects the existence of relations between points and lines that recognise incidence. The preceding view of reality is not new, and the history of this subject is of approaches that are too general (there are conditions on neighbourly points). Our approach is novel in that it is based upon a minimum number of assumptions that yield the existence of dilatations that are translations: the corner stones of coordinatization.  相似文献   
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