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191.
Miraç Ocak Hakan Alp Halit Kantekin Hülya Karadeniz Ümmühan Ocak 《Journal of inclusion phenomena and macrocyclic chemistry》2008,60(1-2):17-24
Three new macrocyclic crown ether ligands containing nitrogen–oxygen donor atoms were designed and synthesized from 1,4-bis(2′-formylphenyl)-1,4-dioxabutane
and 4-nitro-o-phenylenediamine. Ion-pair extraction of metal picrates such as Ag+, Hg2+, Cd2+, Zn2+, Cu2+, Ni2+, Mn2+, Co2+, and Pb2+ from aqueous phase to the organic phase was carried out using the novel ligands. The solvent effect over the metal picrate
extractions was investigated at 25 ± 0.1 °C by using UV–visible spectrometry. The extractability and the values of the extraction
constants (log Kex) were determined for the extracted complexes. 相似文献
192.
Sevinc Z. Topal Kadriye Ertekin Derya Topkaya Serap Alp Berrin Yenigul 《Mikrochimica acta》2008,161(1-2):209-216
Room temperature ionic liquids doped with tris(2,2′-bipyridyl)ruthenium(II)chloride together with chemically and biochemically
inert perfluoro chemicals (PFCs) have been used for the first time for optical O2 sensing purposes.
The response to oxygen of the Ru complex in 1-methyl-3-butylimidazolium tetrafluoroborate (RTIL-I) and 1-methyl-3-butylimidazolium
bromide (RTIL-II) has been evaluated in terms of sensitivity, stability, regeneration ability and response time. The response
times were 2 and 5 s, respectively, and the signal changes were reversible. Better oxygen solubility, enhanced molar absorption
coefficients and photostabilies were found for the RTILs. The stability the Ru complex in RTILs was tested over 12 months
and it is when stored in the ambient air of the laboratory.
Correspondence: Kadriye Ertekin, Fen-Edebiyat Fakultesi, Dokuz Eylul Universitesi, Kimya Bolumu, 35160 Buca, Izmir, Turkey 相似文献
193.
Umit Tunca Gurkan Hizal 《Journal of polymer science. Part A, Polymer chemistry》2000,38(13):2300-2305
A new monomer di(4‐carboxyphenoxy) tetrakis(4‐fluorophenoxy)cyclotriphosphazene 1 was synthesized in a two‐step reaction sequence. The direct polycondensation of 1 and/or 4,4′‐dicarboxydiphenylether with aromatic ethers was carried out in P2O5/methanesulfonic acid (Eaton's reagent) at 120 °C for 3 h to give two series of aromatic poly(ether ketone)s containing cyclotriphosphazene units. The effect of the introduction of the cyclotriphosphazene group on the solubility and thermal properties of these polymers was discussed with relation to the cyclotriphosphazene contents. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2300–2305, 2000 相似文献
194.
Umit Tunca Ali Erdogmus Gurkan Hizal 《Journal of polymer science. Part A, Polymer chemistry》2001,39(17):2993-2997
A novel monomer, 2,2‐bis‐(4′‐fluorobenzoylphenoxy)‐4,4,6,6‐bis[spiro‐(2′,2″‐dioxy‐1′, 1′‐biphenylyl)] cyclotriphosphazene, was synthesized and polymerized with 4,4′‐difluorobenzophenone as a comonomer and 4,4′‐isopropylidenediphenol or 4,4′‐(hexafluoroisopropylidene) diphenol in N,N‐dimethylacetamide at 162 °C for 4 h to give two series of aromatic cyclolinear phosphazene polyetherketones containing bis‐spiro‐substituted cyclotriphosphazene groups. The structure of the monomer was confirmed by 1H, 13C, and 31P NMR. The effect of the incorporation of the bis‐spiro‐substituted cyclotriphosphazene group on the thermal properties of these polymers was investigated by DSC and thermogravimetric analysis. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2993–2997, 2001 相似文献
195.
196.
Polymers containing thermolabile groups were synthesized by various cationic polymerization initiation mechanisms, namely; oxo–carbenium, promoted cationic and activated monomer polymerization. These polymers used in a subsequent blocking step in which azo groups were decomposed and converted into initiating centres from which blocks were grown by means of free radical polymerization. This procedure was applied to specific systems in which cationic polymerizable monomers are tetrahydrofuran (THF), cyclohexene oxide (CHO) and epichlorohydrin (ECH), respectively, and the free radical polymerizable monomer is styrene (St). 相似文献
197.
Tuğrul Yildirim Gülçin Alp Avci Onur Şahin Fatih Akkurt 《Journal of Coordination Chemistry》2019,72(22-24):3502-3517
AbstractFive coordination complexes with Mn2+ (1), Co2+ (2), Ni2+ (3), Cu2+ (4), and Zn2+ (5) containing acesulfame (ace) and N,N-diethylnicotinamide (dena) ligands were synthesized and structural binding properties investigated. Four compounds (1, 2, 4, and 5) were examined with single crystal X-ray diffraction methods. The structures containing Mn(II), Co(II), and Zn(II) were iso-structural. Six-coordination of metal cations were completed with two moles dena and four aqua ligands. The dena ligands were coordinated via pyridine nitrogen as neutral-monodentate. Charge stabilities of the complexes are complemented by two moles monoanionic ace ligands, located outside of the coordination unit. In the Cu(II) complex, the coordination is completed by acidic nitrogen and carbonyl oxygen atoms of two ace ligands and pyridine nitrogen of two moles dena ligands. The coordination to Cu(II) for ace ligands was monoanionic-bidentate. All metal cations in the structure are distorted octahedral. Thermal decomposition of complexes begins with removal of the aqua molecules from the structures and is completed by combustion of organic ligands. The final decomposition products of all structures have been identified as corresponding metal oxides. Some biological applications (anti-fungal/anti-bacterial) were studied using 1–5. 相似文献
198.
199.
Zeynep Alp Alessandro Ciccola Ilaria Serafini Alessandro Nucara Paolo Postorino Alessandra Gentili Roberta Curini Gabriele Favero 《Molecules (Basel, Switzerland)》2022,27(20)
The aim of this research is to study and diagnose for the first time the Polaroid emulsion transfer in the contemporary artist Paolo Gioli’s artworks to provide preliminary knowledge about the materials of his artworks and the appropriate protocols which can be applied for future studies. The spectral analysis performed followed a multi-technical approach first on the mock-up samples created following Gioli’s technique and on one original artwork of Gioli, composed by: FORS (Fiber Optics Reflectance), Raman, and FTIR (Fourier-Transform InfraRed) spectroscopies. These techniques were chosen according to their completely non-invasiveness and no requirement for sample collection. The obtained spectra from FTIR were not sufficient to assign the dyes found in the transferred Polaroid emulsion. However, they provided significant information about the cellulose-based materials. The most diagnostic results were obtained from FORS for the determination of the dye developers present in the mock-up sample which was obtained from Polacolor Type 88 and from Paolo Gioli’s original artwork created with Polacolor type 89. 相似文献
200.
Abdullah Zahid Turan
zlem Ata Ouz Alp Kurucu Atilla Ersz Alper Sarolan Hasancan Okutan 《国际化学动力学杂志》2022,54(1):3-15
The reaction kinetics of a Fischer–Tropsch (FT) process to produce lower olefins was modeled utilizing the experimental data produced using an in-house synthesized iron-based catalyst. Along with FT chain growth reaction that is assumed to follow alkyl mechanism, water–gas shift reaction was also taken into consideration due to its significance. Not only the rate constants but also apparent activation energies were obtained via an integrated approach utilizing multiobjective and constrained nonlinear minimization methods in order to define a model valid at a temperature range instead of a single point. The adaption of a hybrid optimization method utilizing both population- and individual-based techniques enhanced prediction accuracy compared with the case where only multiobjective genetic algorithm is used. Thanks to the developed model, the effect of process parameters on product distribution was investigated. Finally, the kinetic model was compared with Anderson–Schulz–Flory model and the deviations observed were discussed. 相似文献