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81.
The impact of investment lags on investment decision 总被引:1,自引:0,他引:1
Ki Hong Kim Seong Tae Hwang Hyung Sik Oh Deok Joo Lee 《European Journal of Operational Research》2008,190(3):696-707
This paper suggests a valuation framework for an investment project through the concept of real options. Generally, in real asset world, decision time and its payment time are not identical. This so-called investment lag problem should be considered when valuing real assets. When investment lags exist, firms’ accommodation capacities play important roles. In this paper, the real effect of investment lag on investment value is tested upon various conditions. We show the valuation process of real assets under the risk-neutral world. The closed-form formula is also provided for valuing real assets, including R&D project. 相似文献
82.
Jaya Ram Simkhada Seung Sik Cho Seong Ju Park Poonam Mander Yun Hee Choi Hyo Jeong Lee Jin Cheol Yoo 《Applied biochemistry and biotechnology》2010,162(5):1457-1470
Organic solvent- and detergent-resistant proteases are important from an industrial viewpoint. However, they have been less
frequently reported and only few of them are from actinomycetes. A metalloprotease from Streptomyces olivochromogenes (SOMP) was purified by ion exchange with Poros HQ and gel filtration with Sepharose CL-6B. Apparent molecular mass of the
enzyme was estimated to be 51 kDa by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and gelatin zymography. The
activity was optimum at pH 7.5 and 50 °C and stable between pH 7.0 and 10.0. SOMP was stable below 45 °C and Ca2+ increased its thermostability. Ca2+ enhanced while Co2+, Cu2+, Zn2+, Mn2+, and Fe2+ inhibited the activity. Ethylenediaminetetraacetic acid and ethylene glycol-bis (β-aminoethyl ether)-N,N,N′,N′-tetraacetic acid, but not phenylmethylsulfonyl fluoride, aprotinin, and pefabloc SC, significantly suppressed the activity,
suggesting that it might be a metalloprotease. Importantly, it is highly resistant against various detergents, organic solvents,
and oxidizing agents, and the activity is enhanced by H2O2. The enzyme could be a novel protease based on its origin and peculiar biochemical properties. It may be useful in biotechnological
applications especially for organic solvent-based enzymatic synthesis. 相似文献
83.
Influenza vaccine strains have been traditionally developed by annual reassortment between vaccine donor strain and the epidemic virulent strains. The classical method requires screening and genotyping of the vaccine strain among various reassortant viruses, which are usually laborious and time-consuming. Here we developed an efficient reverse genetic system to generate the 6:2 reassortant vaccine virus from cDNAs derived from the influenza RNAs. Thus, cDNAs of the two RNAs coding for surface antigens, haemagglutinin and neuraminidase from the epidemic virus and the 6 internal genes from the donor strain were transfected into cells and the infectious viruses of 6:2 defined RNA ratio were rescued. X-31 virus (a high-growth virus in embryonated eggs) and its cold-adapted strain X-31 ca were judiciously chosen as donor strains for the generation of inactivated vaccine and live-attenuated vaccine, respectively. The growth properties of these recombinant viruses in embryonated chicken eggs and MDCK cell were indistinguishable as compared to those generated by classical reassortment process. Based on the reverse genetic system, we generated 6 + 2 reassortant avian influenza vaccine strains corresponding to the A/Chicken/Korea/MS96 (H9N2) and A/Indonesia/5/2005 (H5N1). The results would serve as technical platform for the generation of both injectable inactivated vaccine and the nasal spray live attenuated vaccine for the prevention of influenza epidemics and pandemics. 相似文献
84.
Seong Hojun Cho Kyoungah Yun Junggwon Kwak Kiyeol Jun Jin Hyung Kim Sangsig 《Solid State Sciences》2010,12(8):1328-1331
In this study, we demonstrate the photogating effects of p-type HgTe nanoparticles (NPs) on an n-type ZnO nanowire (NW). The photogating effects are due to the charge separation of the charge carriers photogenerated in the NPs under illumination and the subsequent accumulation of the photogenerated electrons in the pn junction of the NPs and the NW. The presence of the electrons in the junction reduces the current in the ZnO NW. The photogating effects are proved by the different photocurrent behavior of the ZnO NW to which the HgTe NPs are attached from that of a bare ZnO NW. In addition, the dependence of the photogating effects on the power of the incident light is discussed. 相似文献
85.
Min Hwan Lee Kyung Min Kim Seul Ji Song Sang Ho Rha Jun Yeong Seok Ji Sim Jung Gun Hwan Kim Jung Ho Yoon Cheol Seong Hwang 《Applied Physics A: Materials Science & Processing》2011,102(4):827-834
The bipolar resistive switching mechanisms of a p-type NiO film and n-type TiO2 film were examined using local probe-based measurements. Scanning probe-based current–voltage (I–V) sweeps and surface potential/current maps obtained after the application of dc bias suggested that resistive switching is
caused mainly by the surface redox reactions involving oxygen ions at the tip/oxide interface. This explanation can be applied
generally to both p-type and n-type conducting resistive switching films. The contribution of oxygen migration to resistive
switching was also observed indirectly, but only in the cases where the tip was in (quasi-) Ohmic contact with the oxide. 相似文献
86.
87.
Seong Huh Young Jun Park Alan. J. Lough Moo‐Jin Jun 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):416-417
The title compound, [RuH(C6H8BN4)(C21H21P)2(CO)], possesses two trans‐disposed tri‐p‐tolylphosphines in axial positions and the remaining ligands in equatorial positions. The overall geometry of the RuII ion is a distorted octahedral structure. The P—Ru—P axis deviates from linearity by about 13°. This distortion arises mainly from the steric congestion between the bulky phosphine moieties and the tetrahedral dihydrobis(pyrazol‐1‐yl)borate ligands. 相似文献
88.
Matthew R. Buckley Seong Youl Choi Kentarou Mawatari Hitoshi Murayama 《Physics letters. [Part B]》2009
Determining the spin of new particles is critical in identifying the true theory among various extensions of the Standard Model at the next generation of colliders. Quantum interference between different helicity amplitudes was shown to be effective when the final state is fully reconstructible. However, many interesting new physics processes allow only for partial reconstruction. In this Letter, we show how the interference effect can be unambiguously extracted even in processes that have two-fold ambiguity, by considering the correlation between two decay planes in e+e− collisions. 相似文献
89.
Kyu Hwang Yeon Suk Seong Kim Chung In Um Thomas F. George 《International Journal of Theoretical Physics》2003,42(9):2043-2059
Quantum Hamiltonian systems corresponding to classical systems related by a general canonical transformation are considered. The differential equation to find the unitary operator, which corresponds to the canonical transformation and connects quantum states of the original and transformed systems, is obtained. The propagator associated with their wave functions is found by the unitary operator. Quantum systems related by a linear canonical point transformation are analyzed. The results are tested by finding the wave functions of the under-, critical-, and over-damped harmonic oscillator from the wave functions of the harmonic oscillator, free-particle system, and negative harmonic potential system, using the unitary operator to connect them, respectively. 相似文献
90.
Lee SJ Min A Kim Y Ahn A Chang J Lee SH Choi MY Kim SK 《Physical chemistry chemical physics : PCCP》2011,13(37):16537-16541
The conformational structures of jet-cooled acetaminophen were investigated in the gas phase by resonant 2-photon ionization and UV-UV hole-burning spectroscopy. In contrast to the results from a previous study, two nearly isoenergetic conformers were distinctly found in a supersonic molecular beam expansion and positively identified as the cis and trans isomers of acetaminophen by UV-UV hole-burning spectroscopy. The 0-0 bands of the cis and trans isomers were found at 33518.7 and 33485.6 cm(-1), respectively. The vibronic bands of the two isomers are close-lying and/or partially overlapping due to the small energy difference (33 cm(-1)) between the two 0-0 bands. As a consequence, the recorded resonant 2-photon ionization spectrum is highly congested in the low excitation energy region, which develops continuously into a featureless, broadened spectrum in the high energy region. 相似文献