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21.
Ultraviolet (UV) reflection in the urban constructed environment is not well understood for topical issues such as measuring and modeling the received UV exposure due to that UV reflection for outdoor workers. Both predominantly specular and diffuse reflecting surface types have been identified and investigated for the erythemal UV reflection ratio variation due to solar zenith angle and orientation. This paper presents relationships between erythemal UV reflection ratios measured for non‐horizontal and horizontal surfaces, with predominantly specular surface types indicating stronger relationships with solar zenith angles than diffuse reflecting surfaces types. Erythemal UV exposures caused by the same reflecting surface types at three inclinations are also investigated. Non‐horizontal surfaces can increase erythemal UV exposures compared to erythemal UV exposures received from the same horizontal surface by factors of 1.07–1.46 for specific body sites and by 1.01–1.70 for averages of group body sites for zinc aluminium coated steel sheeting.  相似文献   
22.
Fringing coral reefs provide a unique opportunity to study shallow aquatic ecosystems. A fringing coral reef system located in close proximity to a developed region was considered in this study. In such an environment, the rate of decay of dissolved organic matter is high and the penetration of higher energy ultraviolet‐B (UVB) extends a greater influence on species diversity, particularly upon shallow benthic communities. Results from a 9 month subsurface UVB exposure measurement campaign performed at a site located on the southern Queensland coast (Hervey Bay, 25°S) are presented in this research. For this, a novel dosimetric technique was utilized to measure long‐term subsurface UVB exposures. The resultant data set includes exposure measurements made during the significant La Niña event of late 2010 which resulted in unprecedented high sea surface temperatures and severe flooding across eastern Australia, impacting upon the lagoon regions of the Great Barrier Reef and Queensland's southern estuaries, including the study site. The influence of season, diurnal tidal variation, cloud cover and solar zenith angle were analyzed over the campaign period. Mean minimum daylight water depth was found to be the most significant factor influencing subsurface UVB.  相似文献   
23.
This research presents a novel methodology for deriving the total daily broadband solar UVA (320–400 nm) received by school teachers during their working day from Ozone Monitoring Instrument (OMI) satellite solar noon UVA irradiance measurements for a Queensland subtropical site (27.5°S, 152°E). Daily UVA exposures are weighted to the anatomical human cheek (anterior infra‐orbital region) for teachers wearing and not wearing broad‐brimmed hats. The method utilizes the OMI UVA irradiance data collected daily at high temporal resolution over 2005 to 2016 to derive the total daily UVA exposure to a horizontal plane. These horizontal plane exposures are scaled by factors to take into account the timing of outdoor activity. The relationship between exposures to a horizontal plane and those to a vertical plane and the protection provided by a broad‐brimmed hat was assessed to evaluate the total daily UVA exposures to the cheek for classroom and physical education teaching staff expected to be outside at different periods of the day. The developed method enables the total daily UVA exposure to specific anatomical sites to be evaluated from the satellite solar noon irradiance at locations that do not have access to surface‐based instrumentation capable of recording in the solar UVA waveband.  相似文献   
24.
The molecular recognition in water of neurotransmitter monoamine and trace amine hydrochlorides by p-tert-butylcalix[5]-arene 1 – bearing 4-sulphonatobutoxy groups at the lower rim – has been investigated. According to 1H NMR measurements, the hydrophobic cavity of receptor 1 best binds tyramine hydrochloride, Ka = 5370 ± 870 M? 1.  相似文献   
25.
26.
We numerically investigate the spin glass energy interface problem in three dimensions. We analyze the energy cost of changing the overlap from −1 to +1 at one boundary of two coupled systems (in the other boundary the overlap is kept fixed to +1). We implement a parallel tempering algorithm that simulates finite temperature systems and works with both cubic lattices and parallelepiped with fixed aspect ratio. We find results consistent with a lower critical dimension D c =2.5. The results show a good agreement with the mean field theory predictions.  相似文献   
27.
We get back to the computation of the leading finite size corrections to some random link matching problems, first adressed by Mézard and Parisi [J. Phys. France 48, 1451 (1987)]. In the so-called bipartite case, their result is in contradiction with subsequent works. We show that they made some mistakes, and correcting them, we get the expected result. In the non bipartite case, we agree with their result but push the analytical treatment further. Received 28 April 2002 Published online 14 October 2002 RID="a" ID="a"e-mail: giorgio.parisi@roma1.infn.it RID="b" ID="b"e-mail: matthieu.ratieville@roma1.infn.it  相似文献   
28.
Attractive pi-pi interactions between two of the four outside cavity faces of 1,3-bis-pyridylmethylcalix[4]arene (1) and both faces of 1,4-diiodotetrafluorobenzene (2a) form infinite one-dimensional non-covalent ribbons where the two modules alternate. These ribbons are cross-linked by electron donor-acceptor interactions between picolyl nitrogen atoms of calixarene 1 in one chain and iodine atoms of perfluoroarene 2a in another chain and the two-dimensional supramolecular network 3a is formed. A similar behaviour is also shown by 1,4-dibromotetrafluorobenzene (2b). The halogen bonding and the attractive pi-pi interactions occur in directions which are nearly orthogonal each other. Diiodotetrafluorobenzene, being involved in both these interactions, appears to be a particularly interesting tecton. The ability of electron-poor arenes to elicit the exo-receptor potential of calixarene module by connecting their outside faces through pi-pi interactions may be developed as a new and general binding protocol in calixarene self-assembly processes.  相似文献   
29.
The dependence of the spectral biologically effective solar UV irradiance on the orientation of the receiver with respect to the sun has been determined for relatively cloud-free days at a sub-tropical Southern Hemisphere latitude for the solar zenith angle range 35-64 degrees. For the UV and biologically effective irradiances, the sun-normal to horizontal ratio for the total UV ranges from 1.18 +/- 0.05 to 1.27 +/- 0.06. The sun-normal to horizontal ratio for biologically effective irradiance is dependent on the relative effectiveness of the relevant action spectrum in the UV-A waveband. In contrast to the total UV, the diffuse UV and diffuse biologically effective irradiances are reduced in a sun-normal compared with a horizontal orientation by a factor ranging from 0.70 +/- 0.05 to 0.76 +/- 0.03.  相似文献   
30.
We assume weak, electromagnetic and strong interactions to be asymptotically divergent, and to become strong at very large energies, of the order of the Plank mass. In this picture, the “low-energy” couplings (i.e. in the 102 GeV region) must be near the infrared stable point, and this allows us to put bounds on the number of elementary fermions (quarks and leptons). Similar assumptions on the Higgs couplings give bound on the fermion and on the Higgs boson masses. We consider the cases where weak and electromagnetic interactions are described by the gauge groups SU(2) ? U(1) or SU(2)R ? U(1). The weak neutral current mixing angle is computed in both cases.  相似文献   
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