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61.
Bolton RD Bowman JD Cooper MD Frank JS Hallin AL Heusi PA Hoffman CM Hogan GE Mariam FG Matis HS Mischke RE Nagle DE Piilonen LE Sandberg VD Sanders GH Sennhauser U Werbeck R Williams RA Wilson SL Hofstadter R Hughes EB Ritter MW Grosnick D Wright SC Highland VL McDonough J 《Physical review letters》1986,56(23):2461-2464
62.
Kehlbeck JD Hagerman ME Cohen BD Eliseo J Fox M Hoek W Karlin D Leibner E Nagle E Nolan M Schaefer I Toney A Topka M Uluski R Wood C 《Langmuir : the ACS journal of surfaces and colloids》2008,24(17):9727-9738
Laponite films provide versatile inorganic scaffolds with materials architectures that direct the self-assembly of CdSe quantum dots (QDs or EviTags) and catalytic surfaces that promote the in situ polymerization of polyaniline (PANI) to yield novel nanocomposites for light emitting diodes (LEDs) and solar cell applications. Water-soluble CdSe EviTags with varying, overlapping emission wavelengths in the visible spectrum were incorporated using soft chemistry routes within Na-Laponite host film platforms to achieve broadband emission in the visible spectrum. QD concentrations, composition and synthesis approach were varied to optimize photophysical properties of the films and to mediate self-assembly, optical cascading and energy transfer. In addition, aniline tetramers coupled to CdSe (QD-AT) surfaces using a dithioate linker were embedded within Cu-Laponite nanoscaffolds and electronically coupled to PANI via vapor phase exposure. Nanotethering and specific host-guest and guest-guest interactions that mediate nanocomposite photophysical behavior were probed using electronic absorption and fluorescence spectroscopies, optical microscopy, AFM, SEM, powder XRD, NMR and ATR-FTIR. Morphology studies indicated that Lap/QD-AT films synthesized using mixed solvent, layer by layer (LbL) methods exhibited anisotropic supramolecular structures with unique mesoscopic ordering that affords bifunctional networks to optimize charge transport. 相似文献
63.
64.
Qualitative molecular orbital theory is widely used as a conceptual tool to understand chemical bonding. Symmetry-allowed orbital mixing between atomic or fragment orbitals of different energies can greatly complicate such qualitative interpretations of chemical bonding. We use high-level Amsterdam Density Functional calculations to examine the issue of whether orbital mixing for some familiar second-row homonuclear and heteronuclear diatomic molecules results in net bonding or antibonding character for a given molecular orbital. Our results support the use of slopes of molecular orbital energy versus bond distance plots (designated radial orbital-energy slope: ROS) as the most useful criterion for making this determination. Calculated atomic charges and frontier orbital properties of these molecules allow their acid-base chemistry, including their reactivities as ligands in coordination chemistry, to be better understood within the context of the Klopman interpretation of hard and soft acid-base theory. Such an approach can be extended to any molecular species. 相似文献
65.
J. F. Nagle 《Communications in Mathematical Physics》1969,13(1):62-67
The Slater KDP model defined on d-dimensional tetrahedral lattices is proved to have a phase transition for which the entropy and energy are discontinuous functions at a transition temperaturekT
c
=/ln2, independent of dimensionality. 相似文献
66.
Rivard Christopher J. Duff Brian W. Nagle Nicholas J. 《Applied biochemistry and biotechnology》1998,(1):569-577
Modern municipal sewage waste treatment plants use conventional mechanical and biological processes to reclaim wastewaters.
This process has an overall effect of converting a water pollution problem into a solid waste disposal problem (sludges or
biosolids). An estimated 10 million tons of biosolids, which require final disposal, are produced annually in the United States.
Although numerous disposal options for biosolids are available, including land application, landfilling, and incineration,
disposal costs have risen, partly because of increased federal and local environmental restrictions(1). A novel, thermomechanical biosolids pre-treatment process, which allows for a variety of potential value-added uses, was
developed. This two-step process first employs thermal explosive decompression to inactivate or kill the microbial cells and
viruses. This primary step also results in the rupture of a small amount of the microbial biomass and increases the intrinsic
fluidity of the biosolids. The second step uses shear to effect a near-complete rupturing of the microbial biomass, and shears
the nondigested organics, which increases the overall surface area. Pretreated biosolids may be subjected to a secondary anaerobic
digestion process to produce additional fuel gas, and to provide for a high-quality, easily dewatered compost product. This
novel biosolids pretreatment process was recently allowed a United States patent. 相似文献
67.
TESTING KINETIC MODELS FOR THE BACTERIORHODOPSIN PHOTOCYCLE—II. INCLUSION OF AN O TO M BACKREACTION 总被引:4,自引:0,他引:4
Luis A. Parodi Richard H. Lozier Somendra M. Bhattacharjee John F. Nagle 《Photochemistry and photobiology》1984,40(4):501-506
Abstract Using previously established procedures we have tested a kinetic model of bacteriorhodopsin involving a backreaction from O to M. This model is superior to the previously tested models involving only unidirectional reaction paths. However, the spectrum of O is still too strongly temperature dependent in the red. Therefore, at least one additional feature is necessary to obtain a completely consistent kinetic model of the bacteriorhodopsin photocycle. 相似文献
68.
Nagle PS Quinn SJ Kelly JM O'Donovan DH Khan AR Rodriguez F Nguyen B Wilson WD Rozas I 《Organic & biomolecular chemistry》2010,8(24):5558-5567
Biophysical studies have been carried out on a family of asymmetric guanidinium-based diaromatic derivatives to assess their potential as DNA minor groove binding agents. To experimentally assess the binding of these compounds to DNA, solution phase biophysical studies have been performed. Thus, surface plasmon resonance, UV-visible spectroscopy and circular and linear dichroism have been utilized to evaluate binding constants, stoichiometry and mode of binding. In addition, the thermodynamics of the binding process have been determined by using isothermal titration calorimetry. These results show significant DNA binding affinity that correlates with the expected 1?:?1 binding ratio usually observed for minor groove binders. Moreover, a simple computational approach has been devised to assess the potential as DNA binders of this family of compounds. 相似文献
69.
Szemerédi's regularity lemma proved to be a powerful tool in extremal graph theory. Many of its applications are based on the so-called counting lemma: if G is a k-partite graph with k-partition V1∪?∪Vk, |V1|=?=|Vk|=n, where all induced bipartite graphs G[Vi,Vj] are (d,ε)-regular, then the number of k-cliques Kk in G is . Frankl and Rödl extended Szemerédi's regularity lemma to 3-graphs and Nagle and Rödl established an accompanying 3-graph counting lemma analogous to the graph counting lemma above. In this paper, we provide a new proof of the 3-graph counting lemma. 相似文献
70.
Sirtori C. Barbieri S. Kruck P. Piazza V. Beck M. Faist J. Oesterle U. Collot P. Nagle J. 《Photonics Technology Letters, IEEE》1999,11(9):1090-1092
Optical and electrical characteristics of quantum cascade lasers, made in the GaAs-AlxGa1-xAs material system, show persistent changes at low temperatures, when devices are illuminated with an external white light. The magnitude of the effect is a function of the exposure time and finally saturates. The induced variation on the threshold current density of the lasers is more than 30%. This effect is related to the presence of deep donors (DX centers) in the high aluminum content AlGaAs cladding layers, which under illumination release electrons, thus increasing waveguide losses. By analyzing the light induced variations of the optical characteristics we were able to deduce the waveguide losses of our devices 相似文献