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Natural river networks exhibit regular scaling laws in their topological organization. Here, we investigate whether these
scaling laws are unique characteristics of river networks or can be applicable to general binary tree networks. We generate
numerous binary trees, ranging from purely ordered trees to completely random trees. For each generated binary tree, we analyze
whether the tree exhibits any scaling property found in river networks, i.e., the power-laws in the size distribution, the
length distribution, the distance-load relationship, and the power spectrum of width function. We found that partially random
trees generated on the basis of two distinct types of deterministic trees, i.e., deterministic critical and supercritical
trees, show contrasting characteristics. Partially random trees generated on the basis of deterministic critical trees exhibit
all power-law characteristics investigated in this study with their fitted exponents close to the values observed in natural
river networks over a wide range of random-degree. On the other hand, partially random trees generated on the basis of deterministic
supercritical trees rarely follow scaling laws of river networks. 相似文献
134.
Ho Jung Paik 《General Relativity and Gravitation》2008,40(5):907-919
The angular momentum of the Earth produces gravitomagnetic components of the Riemann curvature tensor, which are of the order
of 10−10 of the Newtonian terms arising from the mass of the Earth. Due to the dragging of the local inertial frame by the spinning
Earth, there are also secular terms, which grow in time. These fields can be detected in principle by a set of orbiting superconducting
gravity gradiometers. The Riemann tensor components for various spacecraft orientations have been computed and the principle
of detecting the gravitomagnetic tidal force has been published. In this paper, we review the conclusions of the earlier analyses
and discuss the feasibility of the gravity gradiometer experiment. 相似文献
135.
Jonghwan Jegal No-June Park Beom-Geun Jo Tae-Young Kim Sim-Kyu Bong Sangho Choi Jin-Hyub Paik Jung-Won Kim Su-Nam Kim Min Hye Yang 《Molecules (Basel, Switzerland)》2021,26(7)
Plants of the genus Wikstroemia are used in Chinese traditional medicine to treat inflammatory diseases, such as arthritis, bronchitis, and pneumonia. The present study was designed to determine whether Wikstroemia ganpi (Siebold and Zucc.) Maxim. offers a potential means of treating 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD) in mice. Symptoms such as redness, edema, and keratinization in AD mice induced by DNCB were alleviated by the co-application of an ethanolic extract of W. ganpi for 2 weeks. The severity of skin barrier function damage was evaluated by measuring TEWL (transepidermal water loss). TEWLs of DNCB sensitized mouse dorsal skin were reduced by the application of a W. ganpi ethanolic extract, and skin hydration was increased. In addition, the infiltration of inflammatory cells into the dermis was significantly reduced, as were blood levels of IgE and IL-4, which play an important role in the expression of AD. The results of this experiment suggest that W. ganpi is a potential therapeutic agent for AD. 相似文献
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Control banding (CB) strategies offer simplified processes for controlling worker exposures in the absence of firm toxicological
and exposure information. The nanotechnology industry is an excellent candidate for applying such strategies with overwhelming
uncertainties of work-related health risks posed by nanomaterials. A recent survey shows that a majority of nanomaterial producers
are not performing a basic risk assessment of their product in use. The CB Nanotool, used internationally, was developed to
conduct qualitative risk assessments to control nanoparticle exposures. Nanotoxicology experts have requested standardization
of toxicological parameters to ensure better utility and consistency of research. Such standardization would fit well in the
CB Nanotool’s severity and probability risk matrix, therefore enhancing the protection of nanotechnology industry workers.
This article further evaluates the CB Nanotool for structure, weighting of risk factors, and utility for exposure mitigation,
and suggests improvements for the CB Nanotool and the research needed to bolster its effectiveness. 相似文献