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191.
Preparation of CTA-based polymer inclusion membrane using calix[4]arene derivative as a carrier for Cr(VI) transport 总被引:1,自引:0,他引:1
Ahmet Kaya Canan Onac Ahmet Surucu Emin Karapinar Hamza K. Alpoguz Begum Tabakci 《Journal of inclusion phenomena and macrocyclic chemistry》2014,79(1-2):103-111
In this work, the transport of Cr(VI) ions from an aqueous donor phase solution to an acceptor phase that contained an acetic acid/ammonium acetate buffer at pH 5 through a polymer inclusion membrane (PIM) containing p-tert-butylcalix[4]arene amine derivative as carrier was studied. The Cr(VI) passed through a PIM comprised of cellulose triacetate as a support and 2-NPOE as a plasticizer. The transport efficiency of Cr(VI) was studied under various experimental conditions, such as effect of carrier concentration, acceptor phase pH, type of plasticizer in the membrane, stirring rate and membrane thickness. The kinetic parameters were calculated as rate constant (k), permeability coefficient (P), and flux (J). The transport efficiency of Cr(VI) was observed to be 95.07 % after 10 h under optimized conditions. The prepared PIM was characterized with Fourier transform infrared spectroscopy and the atomic force microscopy techniques as well as with contact angle measurements. This is an effective method for the removal of Cr(VI) which is toxic for human body and environment from the waste water. 相似文献
192.
193.
S. Kaya 《Zeitschrift für Physik A Hadrons and Nuclei》1933,84(11-12):705-716
194.
In this note, we reply to the comments by Rees and Magyari (2007) on our article (Aydin and Kaya 2007). They mainly stated
that the thermal boundary conditions we defined at the edge of the boundary layer were incompatible with the energy equation.
This is questionable and therefore we will discuss it below. They disclosed that our results were in error. However, this
is quite misleading. Scientifically, they cannot reach such a conclusion without comparing our results with what they thought
to be correct. In fact, this misleading and unproven statement will be shown not to be correct in the following. 相似文献
195.
Ken Hosoya Mari Sakamoto Kunihiko Akai Tomoko Mori Takuya Kubo Kunimitsu Kaya Kazuma Okada Norio Tsujioka Nobuo Tanaka 《Analytical sciences》2008,24(1):149-154
This report describes the development of novel wired chip devices for mu-HPLC analyses. The monolithic capillary column to be wired was prepared using a tri-functional epoxy monomer, tris(2,3-epoxypropyl)isocyanurate with a diamine, 4-[(4-aminocyclohexyl)methyl]cyclohexylamine. The prepared column was evaluated by SEM observation of the sectional structure of column and micro-HPLC. In addition, the reproducibility in the preparation of long capillary columns having nearly 1 m length was extensively examined for applications of novel wired chip devices. The authors demonstrated that the monolithic structure of the prepared long capillary could be finely controlled under the strictly maintained operational conditions and thus the relative standard deviation (RSD) of the column properties such as the number of theoretical plates, retention factor, and permeability could be well controlled to become less than 10%. Furthermore, the wired chip device column showed that its high performance was kept even after chip preparation. 相似文献
196.
We define and investigateCD
Σ,Γ(K, E)-type spaces, which generalizeCD
0-type Banach lattices introduced in [1]. We state that the space CD
Σ,Γ(K, E) can be represented as the space of E-valued continuous functions on the generalized Alexandroff Duplicate of K. As a corollary we obtain the main result of [6, 8]. 相似文献
197.
198.
Fatih Do■an Hakan Akat Ismet Kaya 《高分子科学》2008,(1):47-53
A new polymer,poly(imino isophthaloyl imino(2,4,8,10-tetraoksoaspiro[5,5]undekan-3,9-dipropylene)) [poly(IPIT)]was synthesized by an interfacial polycondensation reaction.The characterization of poly(IPIT)was conducted by using FT-IR,~(13)C-NMR,TG and DTA techniques.The kinetics of the thermal degradation of poly(IPIT)was investigated by thermogravimetric analysis at different heating rates.TG curves showed that the thermal decomposition of poly(IPIT) occurred in three stages.The apparent activation ener... 相似文献
199.
Muharrem Kaya Cengiz Yenikaya Alper Tolga Colak Ferdag Colak 《Russian Journal of General Chemistry》2008,78(9):1808-1815
Two different metal complexes of [Co(HL)(L)(Ac)2]·4H2O (I) and [Ni2(L)2(Ac)2]·4H2O (II), have been synthesized with newly prepared amine-imine-oxime ligand [HL = 3-(4′-aminobiphenyl-4-ylimino)-butan-2-one oxime,
Ac = CH3COO−]. This ligand HL was prepared by the condensation of diacetylmonoxime with benzidine. The structure of the ligand and complexes
have been proposed by elemental analyses, IR, 1H, and 13C NMR, electronic spectra, magnetic susceptibility measurements, mass spectra, molar conductivity and thermo gravimetric analysis.
The molar conductance measurements of the complexes in DMF solution correspond to non electrolytic nature for the complexes.
Octahedral and tetrahedral geometries have been determined to the complexes of Co(III) and binuclear Ni(II) respectively.
The ligand and its metal complexes were tested in vitro for their biological effects. Their activities against two gram-positive
(Bacillus subtilis and Staphylococcus aureus) and one fungal specie (Candida albicans) were found. They were inactive against tested gram negative bacteria.
The text was submitted by authors in English. 相似文献
200.
A high‐level theoretical study into the atmospheric phase hydration,bond dissociation enthalpies,and acidity of aldehydes
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CBS‐Q//B3, G4(MP2), and G4 composite method calculations were used to estimate atmospheric phase standard state (298.15 K, 1 atm) free energies of hydration (ΔhydrG°(g)), hydration equilibrium constants (log Khydr,(g)), bond dissociation enthalpies (BDEs), and enthalpies (ΔdH°(g)) and free energies (ΔdG°(g)) of aldehydic proton acid dissociation for various substituted aldehydes with electron withdrawing and electron releasing groups. Good quality log Khydr,(g) correlations with the Swain–Lupton resonance effect parameters R and R+ were found, allowing extension of the model to predict log Khydr,(g) values for 487 substituted aldehydes having available R‐values and 108 substituted aldehydes having available R+ values. Good correlations were also found between experimental aqueous phase hydration equilibrium constants (log Khydr,(aq)) and summative R/R+ values for peripheral substituents on a range of carbonyl derivatives (aldehydes, ketones, esters, and amides), suggesting that the structure–reactivity modeling approach can be extended to include all possible combinations of R1C(O)R2 carbonyl substitution in both gas and aqueous systems. Computationally derived BDEs and ΔdH°(g)/ΔdG°(g) were in good agreement with the limited experimental and theoretical datasets. BDEs did not generally correlate with any of the Hammett substituent constants or Swain–Lupton parameters considered. Gas phase acidities exhibited high correlation coefficients with Hammett inductive substituent constants (σI) and field effect parameters (F), allowing these to be employed as surrogates for estimating the gas phase aldehydic proton acidities of a larger potential compound range. The resulting models will be of use in predicting the environmental behavior for a broad range of environmentally relevant compounds containing carbonyl functionalities. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献