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1.
Summary Bidentate bridging base polymer complexes of acetylacetonatoiron(II) [Fe(acac)2L]n, where L=pyrazine(pyz), 4,4-bipyridine(bpy),trans-1,2-bis(4-pyridyl)ethylene(bpe), 1,2-bis(4-pyridyl)ethane(bpa) and 4,4-trimethylene bipyridine(tmbpy), have been prepared, characterized and oxidized by iodine to give a range of iron(III) and iron(II) complexes [Fe(acac)2L · Ix]n] in which the FeIII/FeII ratios were established by Mössbauer spectroscopy. The electric conductivities of compressed pellets of the polysalts were obtained. The conductivities and Mössbauer parameters (I.S. and Q.S.) both change with respect to the kind of bidentate bridging bases.The conjugation of bridged ligand markedly affects the conductivity of the complexes. 相似文献
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Kai-Ming Chi Hung-Chang Houa Kuo-Hsien Chen Shin-Guang Shyu Yuh-Sheng Wen 《中国化学会会志》1995,42(3):547-554
Copper(I) complexes of general formula (β-diketonate)Cu(7-AcO-NBD), where 7-AcO-NBD = 7-norbornadienyl acetate and β-diketonate = 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate (1), 1,1,1-trifluoro-2,4-pentanedionate (2), 2,4-pentanedionate (3), 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedionate (4), 4,4,4-trifluoro-1-phenyl-1,3-butanedionate (5), were prepared from reactions of CuCl with Na(β-diketonate) in the presence of 7-AcO-NBD. AH compounds were characterized by elemental analyses, 1H, 13C, 19F NMR and IR spectra. Single-crystal strucutre of compound 1 was determined by X-ray diffraction analysis that showed a mononuclear copper species with coordination of a chelating β-diketonate ligand through two oxygen atoms and the 7-AcO-NBD through its C? C double bond and an oxygen atom in the solid state. For compound 1, the crystal data are: triclinic, space group $ {\rm P}\bar 1 $, a= 5.4519(14) Å, b= 11.852(3) Å, c= 13.304(3) Å, α = 74.721(20)° β = 80.220(20)°, γ= 76.848(19)°, Z = 2, RF = 0.060 and Rw = 0.064. Hot-wall chemical vapor deposition experiments revealed that compound 1 is suitable as a precursor for deposition of copper films in the temperature range 170–260 °C. 相似文献
4.
Chang Chi-I Chen Cheng-Chi Ko Horng-Huey Chen Jih-Jung Cheng Ming-Jen Chao Che-Yi Kuo Yueh-Hsiung 《Chemistry of Natural Compounds》2022,58(3):478-481
Chemistry of Natural Compounds - A new seco-abietanoid, 12-methoxy-7-oxo-6,7-secoabieta-8,11,13-trien-6-oic acid (1), and a known seco-abietanoid,12-hydroxy-6,7-secoabieta-8,11,13-triene-6,7-dial... 相似文献
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Jih-Jung Chen Ming-Jen Cheng Tzong-Huei Lee Yueh-Hsiung Kuo Chao-Tsen Lu 《Molecules (Basel, Switzerland)》2022,27(5)
The genus Cimicifuga is one of the smallest genera in the family Ranunculaceae. Cimicifugae Rhizoma originated from rhizomes of Cimicifuga simplex, and C. dahurica, C. racemosa, C. foetida, and C. heracleifolia have been used as anti-inflammatory, analgesic and antipyretic remedies in Chinese traditional medicine. Inflammation is related to many diseases. Cimicifuga taiwanensis was often used in folk therapy in Taiwan for inflammation. Phytochemical investigation and chromatographic separation of extracts from the roots of Cimicifuga taiwanensis has led to the isolation of six new compounds: cimicitaiwanins A–F (1–6, respectively). The structures of the new compounds were unambiguously elucidated on the basis of extensive spectroscopic data analysis (1D- and 2D-NMR, MS, and UV) and comparison with the literature data. The effect of some isolates on the inhibition of NO production in lipopolysaccharide-activated RAW 264.7 murine macrophages was evaluated. Of the isolates, 3–6 exhibited potent anti-NO production activity, with IC50 values ranging from 6.54 to 24.58 μM, respectively, compared with that of quercetin, an iNOS inhibitor with an IC50 value of 34.58 μM. This is the first report on metabolite from the endemic Taiwanese plant-C. taiwanensis. 相似文献
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Feng-Lin Shyu 《Physics letters. A》2019,383(1):68-75
Electronic and optical properties of armchair stanene nanoribbons are studied within the tight-binding model including spin-orbit coupling in the presence of in-plane electric field. Electric field strongly modulates energy dispersions leading to a zero-gap transition, shift in edge-states, and exhibition of spin-splitting states. Then, the complex dielectric functions in the long wavelength limit is calculated from the gradient approximation. More field-induced transition channels exhibit richer optical spectra which further reveal spin-polarized feature at low frequency. Prominent plasmons in loss spectra come from π–σ mixing orbital. The plasmon peak frequency and height are tuned by field strength. Also, the threshold plasmon frequency linearly decreases as electric field increases and it vanishes at critical field. The reflectance exhibits oscillatory behaviors and shows dip structures with sharp plasmon edge, undergoing a red-shift with increasing field. The calculated results fully show that field-modulations of electronic and optical properties strongly depend on nanoribbon's geometry. 相似文献
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Kuo-Kai Shyu Yu-Te Wu Tzong-Rong Chen Hui-Yun Chen Hui-Hsin Hu Wan-Yuo Guo 《Nonlinear dynamics》2010,61(3):363-372
The fetal cortical complexity is a significant quantification for assessing the development of fetal brain. This study attempts
to quantify the development of fetal cortical complexity using the concept of fractal dimension (FD) analysis. Thirty-two
fetal MR images were selected from Taipei Veterans General Hospital at 27–37 weeks of gestational age (GA). To investigate
the FD of fetal cortical complexity, the entropy based information fractal dimension method (FD
EBI), which is modified from Box-Counting method, was adopted and extended from 2D to 3D. The FD results from overall whole fetal
brains show that the increase of cortical complexity is highly correlated with the gestational age of the fetus. Moreover,
the FD values of right hemispheric brain are larger than those of left hemispheric brain, show that the development of right
hemispheric fetal cortical complexity earlier than the left. These results are in good agreement with normal fetal brain development
and suggest that the FD is an effective means for the quantification of fetal cortical complexity. 相似文献
9.
Left ventricular 4D echocardiogram motion and shape analysis 总被引:1,自引:0,他引:1
The article describes the methodology and the processes of modeling the function and the motion of left ventricle using transesophageal echocardiograph. The parameters can be used in studying the functionality of left ventricle, the status of abnormality of myocardial, and the geometric and morphological of left ventricle in shape analysis. The parameters describes the motion of left ventricle are the left ventricular (LV) floating long axis, the morphological parameters. The LV morphological parameters describe the wall motion, the LV chamber cavity variation, the effective R-ratio of endomyocardial chamber of LV, the area surface curvature, and the global surface curvature circularity. The parameters such as stroke volume, ejection fraction used in evaluation of LV functions are also extracted. 相似文献
10.
This study aims to investigate the complexity of the developing fetal cortical surface based on the notion of fractal dimension
(FD). Forty-four fetal MR images were selected at 22–36 weeks of gestational age (GA) and distributed between two groups:
32 normal fetal brains (excluding twins) and 12 abnormal fetal brains, including twins, mild ventricular dilatation, Cornelia
de Lange syndrome (small brain), and cortical dysplasia (developmental delay). We adopted the commonly used box-counting (BC)
method to estimate the FD of the developing fetal cortical surface. Results from normal fetal brains show that the increase
of cortical complexity is highly correlated with fetal developing weeks of GA. In addition, after 28 weeks of GA, the value
of FD increases more rapidly because of the faster development of convolved folds. In comparison with results from the normal
fetal group, the abnormal fetal brains were examined and the results show that: (1) mild ventricular dilatation has no significant
developing difference compared with normal fetal brains; (2) twins had lower FD than that of normal fetal brains, which may
be a delay of 2–3 weeks; (3) the case of cortical dysplasia also had low FD, indicating that developing delay may mean less
cortical complexity. The results of the normal group are in good agreement with fetal brain development and demonstrate the
effectiveness of FD as a promising means for the quantification of complexity of the fetal cortical surface. 相似文献