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81.
用两个探测器采集光信息而成像的技术——鬼成像已经在X射线波段实现。
对一个物体的常规成像方法是用多像素探测器记录一束光与物体相互作用后的强度与颜色而成像。而鬼成像(ghost imaging)的方法则不同。它根据来自两束光强度的相关性成像,即光与样品相互作用后的物体光束(物光)及未作用的参考光束。严格地说,这种成像方法中,样品不必受到高辐照剂量。然而,迄今为止,鬼成像仅仅用在可见与红外光波段。 相似文献
对一个物体的常规成像方法是用多像素探测器记录一束光与物体相互作用后的强度与颜色而成像。而鬼成像(ghost imaging)的方法则不同。它根据来自两束光强度的相关性成像,即光与样品相互作用后的物体光束(物光)及未作用的参考光束。严格地说,这种成像方法中,样品不必受到高辐照剂量。然而,迄今为止,鬼成像仅仅用在可见与红外光波段。 相似文献
82.
Jeremy J. Intemann Jared F. Mike Min Cai Charles A. Barnes Teng Xiao Robert A. Roggers Joseph Shinar Ruth Shinar Malika Jeffries‐EL 《Journal of polymer science. Part A, Polymer chemistry》2013,51(4):916-923
A series of vinylene‐linked copolymers based on electron‐deficient benzobisthiazole and electron‐rich fluorene moieties were synthesized via Horner–Wadsworth–Emmons polymerization. Three different polymers P1 , P2 , and P3 , were prepared bearing octyl, 3,7‐dimethyloctyl, and 2‐(2‐ethoxy)ethoxyethyl side chains, respectively. The polymers all possessed moderate molecular weights, good solubility in aprotic organic solvents, and high fluorescence quantum efficiencies in dilute solutions. P2 , which bore branched 3,7‐dimethyloctyl side chains, exhibited better solubility than the other polymers, but also exhibited the lowest thermal decomposition temperature of all polymers. Overall, the impact of the side chains on the polymers optical properties in solution was negligible as all three polymers gave similar absorption and emission spectra in both solution and film. Guest‐host light‐emitting diodes using dilute blends of the polymers in a poly(N‐vinylcarbazole) host gave blue‐green emission with P2 exhibiting the highest luminous efficiency, 0.61 Cd/A at ~500 nm. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
83.
84.
Consider the nonlinear coupled elliptic system 相似文献
85.
G. WEIRAUCH M. I. EL IDRISSI J. VANDER AUWERA M. HERMAN A. CAMPARGUE 《Molecular physics》2013,111(11):969-980
The absorption spectrum of dideuteroacetylene has been recorded by intracavity laser absorption spectroscopy (ICLAS) in the 10 200–12 500cm?1 spectral region. Among 25 absorption bands of 12C2D2 rotationally analysed in this spectral region, 17 are newly observed. They include one IIu-Σ+ g and thirteen Σ+ u-Σ+ g bands starting from the vibrational ground state and eleven hot bands from the V 4 = 1 and V 5 = 1 lower states. The rotational structure of two excited levels is affected by a strongly J-dependent interaction with a perturber which induces intensity transfer to extra lines. The coupling is identified as a I-resonance interaction with δu dark states and the vibrational assignment of the perturbers is discussed. Two Σ-Σ bands of the 12C13 CD2 species, present in natural abundance in the sample, could also be identified and rotationally analysed. Most of the corresponding excited vibrational levels of 12C2D2 were unambiguously assigned using the polyad model [Herman, M., el idrissi, M. I., Pisarchik, A., Campargue, A., Gaillot, A.-C., Biennier, L., di lonardo, G. and Fusina, L., 1998, J. chem. Phys., 108, 1377] which allows vibrational energies and B V rotational constants to be predicted. In particular the previously highlighted 1/244 anharmonic resonance is confirmed by energy and intensity features in several {(V 1, V 2, V 3, V 4 = 0, V 5 = 0),(V 1 ?1, V 2 + 1, V 3 V 4 = 2, V 5 = 0)} dyads. Significant deviations between predicted and experimental energy levels are observed for a few levels and discussed. 相似文献
86.
Acta Mathematica Hungarica - For a real biquadratic field, we denote by $$\lambda$$ , $$\mu$$ and $$\nu$$ the Iwasawa invariants of cyclotomic $$\mathbb{Z}_{2}$$ -extension of $$k$$ . We give... 相似文献
87.
88.
A calculated exhaustive set of vibrational state energies in 12C2H2, 13C2H2 and 12C2D2 has been used to analyse the evolution of the integrated number of states with increasing vibrational energy N(E) up to 15000 cm?1, 12000cm?1 and 10000 cm?1 in each isotopomer, respectively. The regular contribution to N(E) was modelled analytically and numerical parameters were fitted. The other expected contribution to N(E), which is of oscillatory nature, was quantified and is discussed using energyand time-dependent theories. Related periods of oscillation and temporal recurrences are interpreted consistently in terms of the constant of the motion Nr = 5v2 + 3v2 + 5v3 + v4 + v5 and of an average vibrational quantum. More pragmatically, the vibrational dynamics appear to be dominated by the bending vibrations, i.e., by the slowest oscillators. 相似文献
89.
Diaryl Sulfoxides from Aryl Benzyl Sulfoxides: A Single Palladium‐Catalyzed Triple Relay Process 下载免费PDF全文
Tiezheng Jia Dr. Ana Bellomo Dr. Sonia Montel Mengnan Zhang Kawtar EL Baina Bing Zheng Prof. Patrick J. Walsh 《Angewandte Chemie (International ed. in English)》2014,53(1):260-264
A novel approach to produce diaryl sulfoxides from aryl benzyl sulfoxides is reported. Optimization of the reaction conditions was performed using high‐throughput experimentation techniques. The [Pd(dba)2]/NiXantPhos catalyst system successfully promotes a triple relay process involving sulfoxide α‐arylation, C? S bond cleavage, and C? S bond formation. The byproduct benzophenone is formed by an additional palladium‐catalyzed process. It is noteworthy that palladium‐catalyzed benzylative C? S bond cleavage of sulfoxides is unprecedented. A wide range of aryl benzyl sulfoxides, as well as alkyl benzyl sulfoxides with various (hetero)aryl bromides were employed in the triple relay process in good to excellent yields (85–99 %). Moreover, aryl methyl sulfoxides, dibenzyl sulfoxides, and dimethylsulfoxide could be utilized to generate diaryl sulfoxides involving multiple catalytic cycles by a single catalyst. 相似文献
90.
V. V. Nedel’ko Yu. M. Mikhailov N. V. Chukanov V. I. Saldin L. V. Ganina V. M. Buznik 《Russian Journal of Physical Chemistry B, Focus on Physics》2011,5(1):26-32
The kinetics and products of the thermal decomposition of hexamethylenetetraammonium dodecahydro-closo-dodecaborate in air, argon, and a vacuum were studied using thermogravimetry, volumetry, mass spectrometry, and IR spectroscopy.
According to the nonisothermal kinetic data, noticeable rates of the formation of volatile products were observed at temperatures
higher than 150°C. The thermal decomposition of the salt occurred in stages. At 160–200°C, the thermal decomposition of hexamethylenetetraammonium
dodecahydro-closo-dodecaborate could not be described by simple kinetic equations. The dependence of the initial reaction rates on inverse
temperature (lnV
0−1/K) was linear, which showed that the thermal decomposition of the salt obeyed the Arrhenius equation V
0 = 109.4 ± 0.6exp[(−20500 ± 1800)/RT], %/min. The obtained temperature dependences of the kinetic parameters of thermolysis were used to predict the time of salt
storage and the conditions of work with it. A comparison of the kinetics of the thermolysis of hexamethylenetetraammonium
dodecahydro-closo-dodecaborate and free hexamethylenetetraamine in open and closed reaction systems showed that the thermolysis of hexamethylenetetraammonium
dodecahydro-closo-dodecaborate was not accompanied by salt dissociation to hexamethylenetetraamine and dodecahydro-closo-dodecaborate acid. The products of its thermolysis volatile under normal conditions were trimethylamine with a small admixture
of nitrogen. The solid residue after thermolysis was a high-porosity insoluble product, whose volume was 6–8 times larger
than the volume of the initial sample. An analysis of the IR spectra of the solid thermolysis product showed that it had a
well-defined salt character. The special features of the IR spectra of initial hexamethylenetetraammonium dodecahydro-closo-dodecaborate and the product of its thermolysis led us to suggest that an acid-base equilibrium of the type [R3N-H+] + A ↔ [R3N… H+…A] occurred in it and, probably, in the initial salt. Here, R3N is the tertiary amino group, and A is the borohydride acid residue. Indications of amorphization allowed us to suggest that
polymer structures were formed as a result of intramolecular interaction between the borohydride anion and onium cation. 相似文献