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71.
The Reaction of Ph3AsCl2 with Acetonitrile. Crystal Structures of [Ph3AsNC(Me)C(AsPh3)CN]+Cl– and of the Palladium Molecular Complex [Ph3AsNC(Me)C(AsPh3)CN–PdCl3] In the presence of potassium hydride the reaction of Ph3AsCl2 with acetonitrile leads to [Ph3AsNC(Me) · C(AsPh3)CN]+Cl– ( 1 ), which is characterized by its infrared spectrum and by a crystal structure analysis. 1 can be explained as an insertion reaction of acetonitrile into an ylidic As–C bond of the primarily formed [(Ph3As)2CCN]Cl. 1 : Space group P1, Z = 2, lattice dimensions at –70 °C: a = 991.9(1), b = 1255.2(1), c = 1381.3(1) pm, α = 81.64(1)°, β = 80.12(1)°, γ = 78.17(1)°; R1 = 0.051. 1 reacts with palladium(II) chloride to give the molecular complex [Ph3AsNC(Me)C(AsPh3)CN–PdCl3] ( 2 ) with zwitterionic structure. The fragment {PdCl3–} is terminally bonded at the nitrogen atom of the CCN group of the cation of 1 in a linear arrangement CCNPd. 2 · CH3CN: Space group P21, Z = 2, lattice dimensions at –90 °C: a = 1079.2(1), b = 1261.5(1), c = 1560.9(1) pm; β = 110.20(1)°; R1 = 0.0283. 相似文献
72.
Synthesis and Crystal Structures of the homoleptic Phosphoraneiminato Cations [E(NPPh3)3]+ (E = S, Se, Te) with Iodide and Triiodide Counter Ions N‐Iod‐triphenylphosphaneimine, INPPh3, reacts with the chalcogenes sulfur, selenium and tellurium in boiling tetrahydrofuran to give the phosphoraneiminato complexes [E(NPPh3)3]+[1/2 I3–, 1/2 I–] · THF (E = S ( 1 ), E = Se ( 2 )) and [Te(NPPh3)3]+I3– ( 3 ), respectively. The componds form red crystals which are characterized by IR spectroscopy and by crystal structure determinations. The homoleptic cations [E(NPPh3)3]+ have pyramidal structures with short EN and PN bond lengths, corresponding to double bonds. 1 : Space group Pa 3, Z = 8, lattice dimensions at –80 °C: a = b = c = 2192.9(1) pm, R1 = 0.0299. 2 : Space group Pa 3, Z = 8, lattice dimensions at –80 °C: a = b = c = 2202.5(1) pm, R1 = 0.0357. 3 : Space group Pca21, Z = 4, lattice dimensions at –90 °C; a = 1075.8(2); b = 1988.8(4); c = 2437.2(3) pm, R1 = 0.0443. 相似文献
73.
Chiral Gallium and Indium Alkoxometalates Li2(S)‐BINOLate ((S)‐BINOL = (S)‐(–)‐2,2′‐Dihydroxy‐1,1′‐binaphthyl) generated by dilithiation of (S)BINOL with two equivalents nBuLi was reacted with GaCl3 und InCl3 in THF to the alkoxometalates [{Li(THF)2}{Li(THF)}2{Ga((S)‐BINOLate)3}] ( 1 ) and [{Li(THF)2}2{Li(THF)}{In((S)‐BINOLate)3}] · [{Li(THF)2}{Li(THF)}2{In((S)‐ BINOLate)3}]2 ( 3 ), respectively. 1 and 3 crystallize from THF/toluene mixtures as 1 · 2 toluene and 3 · 8 toluene. The treatment of PhCH2GaCl2 with Li2(S)‐BINOLate in THF under reflux, followed by recrystallization of the product from DME gives the gallate [{Li(DME)}3{Ga((S)BINOLate)3}] · 1.5 THF ( 2 · 1.5 THF). 1 – 3 were characterized by NMR, IR and MS techniques. In addition, 1 · 2 toluene, 2 · 1.5 THF and 3 · 8 toluene were investigated by X‐ray structure analyses. According to them, a distorted octahedral coordination sphere around the group 13 metal was formed, built‐up by three BINOLate ligands. The three Li+ counter ions act as bridging units by metal‐oxygen coordination. The coordination sphere of the Li+ ions was completed, depending on the available space, by one or two THF ligands ( 1 · 2 toluene, 3 · 8 toluene) and one DME ligand ( 2 · 1.5 THF), respectively. The sterical dominance of the BINOLate ligands can be shown by the almost square‐planar coordination of the Li+ ions in 2 · 1.5 THF giving a small twisting angle of only 17°. 相似文献
74.
Lotf Ali Saghatforoush Soheila Sanati Robabeh Mehdizadeh Mohammad Hasanzadeh 《Superlattices and Microstructures》2012
Cadmium hydroxide (Cd(OH)2) microcrystals were synthesized in ethanol–water medium by using cadmium chloride as cadmium source and 1,10-phenanthroline as complexation agent under solvothermal condition. The sample was characterized by FT-IR, X-ray diffraction (XRD), scanning electron microscopy (SEM) and TEM. The as-prepared Cd(OH)2 product were transformed to hexagonal CdO nanocubes by thermal treatment in air at 500 °C. The possible growth mechanism for the formation of different morphologies at basic medium has been proposed. DPV experiments were carried out for the simultaneous determination of norfloxacin and lomefloxacin in the acetate buffer solution with pH 4.5. 相似文献
75.
Kobra Omidfar Solmaz Kia Soheila Kashanian Malihe Paknejad Afsaneh Besharatie Susan Kashanian Bagher Larijani 《Applied biochemistry and biotechnology》2010,160(3):843-855
Digoxin is widely used as a cardiac glycoside drug in the treatment of various heart conditions. Because it is a toxic drug, it should be regularly monitored in the serum of patients under treatment. In this study, colloidal nanogold is synthesized and the preparation of nanogold-labeled monoclonal antibody probe to digoxin is described under optimal conditions. In addition, an immunochromatographic (IC) method for digoxin analysis employing nanogold-labeled probe is developed. With this technique, it requires only 5 min to complete the quantitative detection of digoxin. The detection time is decreased 20–30 times in comparison to radioimmunoassay (RIA). The sensitivity to digoxin was about 2 ng/ml by naked eye, which is within the therapeutic and toxic ranges of digoxin. The results of serum samples obtained by IC strip were in agreement with those obtained by RIA. The IC strip was sufficiently sensitive and accurate to be used for the rapid detection of digoxin in serum samples. 相似文献
76.
A fast, general, environmentally friendly, and facile method for preparation of 5, 5-disubstituted hydantoins from the reaction between ketone (or aldehyde) derivatives with KCN and ammonium carbonate under microwave irradiation is presented. The microwaves remarkably accelerated this reaction, the reaction times decreased dramatically, the reaction conditions were milder, and the yields were also greater. Also a comparative study of microwave versus classical conditions has been done. All the products were characterized by infrared, NMR, and CHN analysis, and their melting points are identical to those of the known compounds reported in the literature. This method might be useful in the future for the preparation of similar derivatives. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resources: Full experimental and spectral details.] 相似文献
77.
Bahman Tamami Hamed Allahyari Soheila Ghasemi Fatemeh Farjadian 《Journal of organometallic chemistry》2011,696(2):594-599
Novel catalytic system based on palladium nanoparticles supported on poly (N-vinylpyrrolidone) (PVP) grafted silica was prepared. Aminopropylsilica was reacted with acryloyl chloride to form acrylamidopropylsilica, and onto this functionalized silica vinylpyrrolidone monomer was polymerized by free-radical polymerization. The complexation of PVP-grafted silica with PdCl2 was carried out to obtain the heterogeneous catalytic system. X-ray diffraction (XRD) technique and transmission electron microscopy (TEM) image showed that palladium dispersed through the support in nanometer size. This catalytic system exhibited excellent activity in cross-coupling reactions of aryl iodides, bromides and also chlorides with olefinic compounds in Heck-Mizoraki reactions in short reaction time and high yields. Elemental analysis of Pd by inductively coupled plasma (ICP) technique and hot filtration test showed low leaching of the metal into solution from the supported catalyst. The catalyst can be reused several times in repeating Heck reaction cycles without considerable loss in its activity. 相似文献
78.
Soheila Kharratian Donato Conteduca Barbara Procacci Daniel J. Shaw Neil T. Hunt Thomas F. Krauss 《Chemical science》2022,13(43):12858
Vibrational spectroscopy is an important tool in chemical and biological analysis. A key issue when applying vibrational spectroscopy to dilute liquid samples is the inherently low sensitivity caused by short interaction lengths and small extinction coefficients, combined with low target molecule concentrations. Here, we introduce a novel type of surface-enhanced infrared absorption spectroscopy based on the resonance of a dielectric metasurface. We demonstrate that the method is suitable for probing vibrational bands of dilute analytes with a range of spectral linewidths. We observe that the absorption signal is enhanced by 1–2 orders of magnitude and show that this enhancement leads to a lower limit of detection compared to attenuated total reflection (ATR). Overall, the technique provides an important addition to the spectroscopist''s toolkit especially for probing dilute samples.A novel surface-enhanced infrared absorption (SEIRA) spectroscopy method exploits the resonance of a dielectric metasurface to provide strong field enhancement at a microscale depth, making it suitable for analysis of dilute liquid samples. 相似文献
79.
Crystal Structures of [Et3PNAsPh3]2[Ag2Br4] and [Et3PNAsPh3]2[Pd2Br6] Colourless single crystals of [Et3PNAsPh3]2[Ag2Br4]( 1 ) and red single crystals of [Et3PNAsPh3]2[Pd2Br6]( 2 ) have been isolated from saturated solutions in acetonitrile of equivalent mixtures of [Et3PNAsPh3]Br with AgBr and PdBr2, respectively. Both complexes were characterized by IR spectroscopy and by crystal structure determinations. 1 : Space group P1¯, Z = 1, lattice dimensions at ‐70°C: a = 985.0(2), b = 1042.2(5), c = 1345.8(5) pm, α = 102.88(2)°, β = 105.73(2)°, γ = 94.94(2)°, R1 = 0.0577. 2 : Space group P21/c, Z = 2, lattice dimension at ‐70°C: a = 1003.0(1), b = 1371.8(2), c = 1974.0(1) pm, β = 93.30(1)°, R1 = 0.0458. The dimeric anions of 1 and 2 form planar, centrosymmetric complex units. 相似文献
80.
Mohammad Reza Ganjali Morteza Rezapour Mohammad Reza Pourjavid Soheila Haghgoo 《Analytical sciences》2004,20(7):1007-1011
N-[2-[4-[[[(Cyclohexylamino)carbonyl]amino]sulfonyl]phenyl]ethyl]-5-methyl pyrazine carboxamide (glipizid) was explored as an electro-active material for preparing a polymeric membrane-based sensor selective to samarium ions. The membrane incorporated 30% poly(vinyl chloride) (PVC), 53% benzyl acetate (BA), 11% glipizid and 6% sodium tetraphenyl borate. When coated on the surface of a graphite electrode, it exhibits Nernstian responses in the concentration range of 1.0 x 10(-5) to 1.0 x 10(-10) M, with a detection limit of 8.0 x 10(-11)M samarium. The electrode shows high selectivity towards samarium over several cations (alkali, alkaline earth, transition and heavy metal ions), and specially lanthanide ions. The proposed sensor has a very short response time (< 15 s), and can be used in a wide pH range for at least ten weeks. It was used as an indicator electrode in potentiometric titration of Sm(III) ions with an EDTA solution, and for determination of samarium in binary and ternary mixtures. 相似文献