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61.
Magnetic properties of glass ceramics derived from glasses with composition 41CaO·(52−x)SiO2·4P2O5·xFe2O3·3Na2O (2?x?10 mol% iron oxide (Fe2O3)) are reported. Structural investigation revealed the presence of nanocrystalline magnetite phase in the heat-treated samples containing x?2 mol% Fe2O3. Magnetic hysteresis cycles of the glass-ceramic samples were obtained with a maximum applied field of ±20 kOe as well as a low field of ±500 Oe, in order to evaluate the potential of these glass ceramics for hyperthermia treatment of cancer. Samples with x>2 mol% of iron oxide exhibited magnetic behavior similar to soft magnetic materials with low coercivity. The evolution of magnetic properties in these samples as a function of iron oxide molar concentration is correlated with the amount and crystallite size of magnetite phase present in them. 相似文献
62.
Cover Picture: Short Chemoenzymatic Total Synthesis of ent‐Hydromorphone: An Oxidative Dearomatization/Intramolecular [4+2] Cycloaddition/Amination Sequence (Angew. Chem. Int. Ed. 17/2014)
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Vimal Varghese Prof. Tomas Hudlicky 《Angewandte Chemie (International ed. in English)》2014,53(17):4251-4251
63.
64.
Methylindium(III) dithiolate complexes of the general formulae [Me2In(S∩S)] ( 1 ) and [MeIn(S∩S)2] ( 2 ) [S∩S = (EtO)2PS2?, (PriO)2PS2?, Et2NCS2?, , O(CH2CH2)2NCS2?, EtOCS2? and PriOCS2?] have been isolated conveniently by the reaction of Me3In·OEt2 with In(S∩S)3 ( 3 ) in an appropriate stoichiometry. Both 1 and 2 have been characterized by indium analysis, IR, NMR (1H, 13C{1H} and 31P{H}) and mass spectral data. NMR data of 3 are also included for comparison. The Me–In and S∩S resonances are sensitive to the number of methyl groups attached to indium metal. The mass spectral data indicate that these complexes are monomeric in nature. The thermal behavior of a few complexes has been investigated. The xanthate and dithiocarbamate complexes on pyrolysis under dynamic vacuum or flowing nitrogen atmosphere gave either In2S3 or a mixture of InS, In2S3 and In6S7, which were characterized using EDAX and powder XRD. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
65.
Cycloroylenol, a new tetracyclictriterpene in the latex of Euphorbia royleana Boiss is shown to have structure () 相似文献
66.
Vimal K. Jain 《Transition Metal Chemistry》1996,21(6):494-497
Summary Binuclear PdII and PtII complexes of the type [M2Cl2(-Opy)2(PR3)2] [M = Pd or Pt; Opy = 2-OC5H4N (2-hydroxypyridinate ion); PR3 = PEt3, Pn-Bu3, PMe2Ph or PMePh2] were synthesized and characterized by elemental analysis, 1H- and 31P-n.m.r. spectroscopies. The Pd complexes exist in the sym trans form, whereas the corresponding Pt complexes were generated as different isomers. 相似文献
67.
The oxidation of H2NOH is first-order both in [NH3OH+] and [AuCl4
–]. The rate is increased by the increase in [Cl–] and decreased with increase in [H+]. The stoichiometry ratio, [NH3OH+]/[AuCl4
–], is 1. The mechanism consists of the following reactions.
The rate law deduced from the reactions (i)–(iv) is given by Equation (v) considering that [H+] K
a.
The reaction (iii) is a combination of the following reactions:
The activation parameters for the reactions (ii) and (iii) are consistent with an outer-sphere electron transfer mechanism. 相似文献
68.
We report the thermal and spectroscopic analysis of the carbon nanotubes (CNTs)-doped nematic liquid crystal (NLC) material. The CNTs have been oriented in the p-ethoxybenzylidene p-butylaniline NLC. The thermal study of the CNTs doped nematic mixtures shows a significant decrease in the isotropic to nematic phase transition temperature. However higher doping concentration of CNTs has led to the further increase in transition temperature. The UV-Visible spectroscopy has been attempted on the CNTs/NLC mixtures at room temperature. The investigated NLC present one absorption band corresponding to π–π* electronic transition. A red shift of λmax with the increasing concentration of CNTs in the mixture has been observed. The band gap of NLC has been found to decrease after the doping of CNTs. The absorbance was measured for the UV light, polarized parallel and perpendicular to the LC director in the planar aligned cell. 相似文献
69.
M. Punnam Chander K. Vinod Kumar Chandan Lall R. Vimal Raj 《Natural product research》2016,30(10):1190-1192
Leaves of the plant Boesenbergia rotunda are used by the Nicobarese tribe of Andaman and Nicobar Islands, India, to prepare traditional medicine for treating fever, headache and body ache. In the present investigation, methanol fraction of these leaves were analysed by GC/MS that revealed the presence of 25 compounds. The anti-leptospiral activity of methanol crude extract was determined by both microdilution and macrodilution methods. The MICs of the extract were tested against 24 pathogenic leptospiral strains and ranged between 62.5–125 μg/mL in both microdilution and macrodilution. The range of MBCs was 250 and 500 μg/mL in macrodilution and microdilution respectively. The crude extract was subjected to cytotoxic studies and found to have negligible or no haemolytic activity, exhibiting IC50 values of greater than 4 mg/mL. Further in vivo studies are needed to investigate the pharmacological and toxicological properties of Boesenbergia rotunda, before it can be considered as a new anti-leptospiral agent. 相似文献
70.
Effect of Molecular Interactions on Electron‐Transfer and Antioxidant Activity of Bis(alkanol)selenides: A Radiation Chemical Study
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Pavitra V. Kumar Dr. Beena G. Singh Dr. Prasad P. Phadnis Dr. Vimal K. Jain Dr. K. Indira Priyadarsini 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(34):12189-12198
Understanding electron‐transfer processes is crucial for developing organoselenium compounds as antioxidants and anti‐inflammatory agents. To find new redox‐active selenium antioxidants, we have investigated one‐electron‐transfer reactions between hydroxyl (.OH) radical and three bis(alkanol)selenides (SeROH) of varying alkyl chain length, using nanosecond pulse radiolysis. .OH radical reacts with SeROH to form radical adduct, which is converted primarily into a dimer radical cation (>Se∴Se<)+ and α‐{bis(hydroxyl alkyl)}‐selenomethine radical along with a minor quantity of an intramolecularly stabilized radical cation. Some of these radicals have been subsequently converted to their corresponding selenoxide, and formaldehyde. Estimated yield of these products showed alkyl chain length dependency and correlated well with their antioxidant ability. Quantum chemical calculations suggested that compounds that formed more stable (>Se∴Se<)+, produced higher selenoxide and lower formaldehyde. Comparing these results with those for sulfur analogues confirmed for the first time the distinctive role of selenium in making such compounds better antioxidants. 相似文献