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81.
Mustafa Tombul Kutalmis Guven Orhan Büyükgüngr Huseyin Aktas Tahsin Nuri Durlu 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(9):m430-m432
In the title compound, poly[(μ3‐boric acid)‐μ4‐maleato‐dipotassium], [K2(C4H2O4){B(OH)3}]n, there are two independent K+ cations, one bonded to seven O atoms (three from boric acid and four from maleate), and the other eight‐coordinate via three boric acid and four maleate O atoms and a weak η1‐type coordination to the C=C bond of the maleate central C atoms. Hydrogen bonding links the boric acid ligands and maleate dianions, completing the packing structure. 相似文献
82.
83.
Orhan Özdemir Mustafa Anutgan Tamila Aliyeva-Anutgan İsmail Atılgan Bayram Katırcıoğlu 《Journal of Non》2009,355(14-15):851-859
Both dc and ac transport characteristics of plasma enhanced chemical vapor deposited (PECVD) boron nitride (BN) thin film was investigated by dc current vs. dc voltage measurement at different temperatures and admittance vs. gate voltage at various frequencies/temperatures, respectively. MIM ≡ metal (Al)-insulator (BN)-metal (Al) or MIS ≡ metal (Al)-BN-semiconductor (p-Silicon) test devices were conventionally produced. Both conductivity anisotropy and dc/ac detailed transport mechanism were analyzed within the frame of a turbostratic structure (t-BN), interfacing the substrate by a thin amorphous layer (a-BN). This defective BN film has been justified by both infrared (IR) analysis and indirectly by the resulting electrical transport behavior. Transport and its variations as a function of temperature/frequency are in agreement with a hopping mechanism across Gauss-like energy distributed localized deep traps. 相似文献
84.
Hümeyra Paaolu Ahmet Karada Fatma Tezcan Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):m93-m94
In the novel transition metal isothiocyanate complex of N‐(2‐hydroxyethyl)ethylenediamine (hydet‐en) with copper, [Cu(NCS)2(C4H12N2O)], the Cu atom lies in a distorted square‐pyramidal environment, coordinated by four N atoms in the basal plane and an apical O atom. The hydet‐en ligand is N,N,O‐tridentate, in contrast to the disposition in previously studied complexes, while the isothiocyanate ions act as N‐atom donor ligands. The monomeric units are linked to one another by hydrogen bonds. 相似文献
85.
(2,9‐Dimethyl‐1,10‐phenanthroline‐κ2N,N′)(pyridine‐2,6‐dicarboxylato‐κ3O2,N,O6)copper(II) trihydrate
Ibrahim Uar Ahmet Bulut Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(11):m479-m481
The copper(II) centre in the mononuclear title complex, [Cu(C7H3NO4)(C14H12N2)]·3H2O, is surrounded by one bidentate 2,9‐dimethyl‐1,10‐phenanthroline (dmphen) ligand and one tridentate pyridine‐2,6‐dicarboxylate ligand, and exhibits a distorted square‐pyramidal geometry. The crystal packing involves both hydrogen‐bonding and π–π interactions. The solvent water molecules link monomers to one another through hydrogen‐bonding interactions, forming ladder‐like chains in the bc plane. Face‐to‐face and slipped π–π interactions also occur between dmphen rings of neighboring molecules and are responsible for interchain packing. 相似文献
86.
brahim Uar Figen Arslan Ahmet Bulut Hasan budak Hals
lmez Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(10):m523-m525
The crystal structure of the mononuclear title complex, [CuCl2(C10H8N4)(H2O)]·H2O, shows an s‐cis/E/s‐trans‐configured di‐2‐pyridyldiazene ligand, with the square‐pyramidal CuII ion coordinated to one pyridyl and one diazene N atom together with two Cl atoms and one aqua ligand. The crystal packing involves both hydrogen‐bonding and π–π interactions. The solvent water molecule links three monomers to one another through hydrogen‐bonding interactions in which two monomers are linked via chloro ligands and the third via the aqua ligand. Face‐to‐face and weak slipped π–π interactions also occur between di‐2‐pyridyldiazene moieties, and these interactions are responsible for the interchain packing. 相似文献
87.
In the present paper, we study a Korovkin type approximation theorem in the setting of \(K_{a}\)-convergence that contains the classical result. We also study the rate of \(K_{a}\)-convergence and afterwards, we give some concluding remarks. 相似文献
88.
Muharrem Diner Namk
zdemir M. Emin Günay Bekir etinkaya Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(8):m373-m375
The title complex, [RhBr(C8H12)(C19H22N2O2)], has a distorted square‐planar geometry. There are two molecules, A and B, in the asymmetric unit. The Rh—C bond distance between the N‐heterocyclic ligand and the metal atom is 2.039 (2) Å in molecule A and 2.042 (2) Å in molecule B. The angle between the carbene heterocycle and the coordination plane is 87.56 (12)° in molecule A and 87.03 (11)° in molecule B. It is shown that the average Rh—C(COD) (COD is cyclooctadiene) distance is linearly dependent on the Rh—C(imidazolidine) distance in this type of compound. This can be ascribed to the steric hindrance produced by the packing. The crystal structure contains intramolecular C—H⋯O and intermolecular C—H⋯Br interactions. 相似文献
89.
In this paper we develop the main aspects of the Bohman–Korovkin theorem on approximation of continuous functions with the use of A-statistical convergence and matrix summability method which includes both convergence and almost convergence. Since statistical convergence and almost convergence methods are incompatible we conclude that these methods can be used alternatively to get some approximation results. 相似文献
90.