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61.
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
62.
Circulating tumor cells (CTCs) present in the bloodstream are strongly linked to the invasive behavior of cancer; therefore, their detection holds great significance for monitoring disease progression. Currently available CTC isolation tools are often based on tumor-specific antigen or cell size approaches. However, these techniques are limited due to the lack of a unique and universal marker for CTCs, and the overlapping size between CTCs and regular blood cells. Dielectrophoresis (DEP), governed by the intrinsic dielectric properties of the particles, is a promising marker-free, accurate, fast, and low-cost technique that enables the isolation of CTCs from blood cells. This study presents a continuous flow, antibody-free DEP-based microfluidic device to concentrate MCF7 breast cancer cells, a well-established CTC model, in the presence of leukocytes extracted from human blood samples. The enrichment strategy was determined according to the DEP responses of the corresponding cells, obtained in our previously reported DEP spectrum study. It was based on the positive-DEP integrated with hydrodynamic focusing under continuous flow. In the proposed device, the parylene microchannel with two inlets and outlets was built on top of rectangular and equally spaced isolated planar electrodes rotated certain degree relative to the main flow (13°). The recovery of MCF7 cells mixed with leukocytes was 74%–98% at a frequency of 1 MHz and a magnitude of 10–12 Vpp. Overall, the results revealed that the presented system successfully concentrates MCF7 cancer cells from leukocytes, ultimately verifying our DEP spectrum study, in which the enrichment frequency and separation strategy of the microfluidic system were determined. 相似文献
63.
64.
P. Tasli S. B. Lisesivdin A. Yildiz M. Kasap E. Arslan S.
zcelik E. Ozbay 《Crystal Research and Technology》2010,45(2):133-139
Resistivity and Hall effect measurements were carried out as a function of magnetic field (0‐1.5 T) and temperature (30‐300 K) for Al0.88In0.12N/AlN/GaN/AlN heterostructures grown by Metal Organic Chemical Vapor Deposition (MOCVD). Magnetic field dependent Hall data were analyzed by using the quantitative mobility spectrum analysis (QMSA). A two‐dimensional electron gas (2DEG) channel located at the Al0.88In0.12N/GaN interface with an AlN interlayer and a two‐dimensional hole gas (2DHG) channel located at the GaN/AlN interface were determined for Al0.88In0.12N/AlN/GaN/AlN heterostructures. The interface parameters, such as quantum well width, the deformation potential constant and correlation length as well as the dominant scattering mechanisms for the Al0.88In0.12N/GaN interface with an AlN interlayer were determined from scattering analyses based on the exact 2DEG carrier density and mobility obtained with QMSA. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
65.
Aytek Yılmaz Bilge Taner Pervin Deveci Aslıhan Yılmaz Obalı Uğur Arslan Ertan Şahin H. İsmet Uçan Emine Özcan 《Polyhedron》2010
A new vic-dioxime ligand bearing an important pharmacophore substituent, anti-1-(4-benzylpiperazine-1-yl) phenylglyoxime (LH2) (Scheme 1), has been synthesized and its nickel(II) complex was obtained by the reaction of NiCl2·6H2O and the ligand. The characterization of the newly formed compounds was performed by elemental analysis, FT-IR, 1D NMR (1H, 13C, DEPT), 2D NMR (HMBC), ESI mass-spectrometry, TG/DTA, X-ray crystallography. The antibacterial activity was also studied against Staphylococcus aureus ATCC 25923, Streptococcus mutans RSHM 676, Enterococcus faecalis ATCC 29212, Lactobacillus acidophilus RSHM 06029, Escherichia coli ATCC 25922, E. coli ATCC 35218, Pseudomonasaeruginosa ATCC 27853. The antimicrobial test results indicated that all the compounds have mild antibacterial activity against both Gram negative and Gram positive bacterial species. 相似文献
66.
Rainer Kahner Benedikt Waerder Hasan Kemal Arslan Heinz Rehage 《Colloid and polymer science》2010,288(4):461-468
In this publication we describe a new self-association process, which leads to the formation of ultra-thin alginate layers
at the interface between oil and water. The water phase contains a highly dilute solution of sodium alginate. These macromolecules
are negatively charged and they are not surface active. The oil phase contains a small concentration of positively charged
surfactants. At the interface between oil and water, the cationic surfactants tend to form complexes with the negatively charged
alginate polyelectrolytes in the aqueous solutions. This leads to striking adsorption processes of the solved polysaccharide
molecules at the oil-water interface. Upon the addition of calcium ions, a cross-linking process sets in and one obtains the
thin viscoelastic membranes, which are anchored at the interface between oil and water. The thickness of these membranes is
of the order of 0.2 mm. Similar structures can also be formed by solving positively charged Gemini surfactants in the oil
phase. In this case, the cationic surfactant molecules induce the adsorption processes of alginate macromolecules, and they
also act as cross-linking compounds. In a series of experiments, we measured the surface rheological properties of these ultra-thin
alginate membranes. The results of these investigations point to the presence of electrostatically stabilized membranes. Special
interest was given to the influence of the guluronate content of the alginates, which is important for the cross-linking mechanism
according to the egg-box model. Finally, this article finishes with the discussion of the proposed building mechanisms of
these membranes. 相似文献
67.
68.
Cevdet Akbay Yatzka Hoyos Edward Hooper Hakan Arslan Syed A.A. Rizvi 《Journal of chromatography. A》2010,1217(32):5279-5287
Two cationic gemini surfactants with pyrrolidinium or alkyl ammonium head groups with but-2-yne spacers, but with the same length hydrocarbon chain have been characterized with respect to their aggregation behaviors and separation power as pseudostationary phases (PSPs) for micellar electrokinetic chromatography (MEKC). They were compared with a commonly used PSP, sodium dodecylsulfate (SDS). The results suggest that the head groups of the surfactants have some effect on physicochemical properties such as critical micelle concentration (CMC), C20, γCMC, partial specific volume, methylene selectivity and mobilities of the surfactants. CMC values of G1, G2 and SDS in pure water were found to be 0.82, 0.71, and 8.08 mM, respectively; they were reduced to 0.21, 0.11, and 3.0 mM when measured in 10 mM phosphate buffer at pH 7.0. G1 (αCH2=2.74) and G2 (αCH2=2.48) provided the most and the least hydrophobic environment, respectively. According to their partial specific volumes, geminis were found to have more flexible structures as compared with sodium dodecylsulfate. The effects of the head group structure were also characterized with the linear solvation energy relationship (LSER) model, which was able to evaluate the role of solute size, polarity/polarizability, and hydrogen bonding on retention and selectivity. The cohesiveness, hydrogen bond acidic and basic character of the surfactant systems were found to have the most significant influence on selectivity and MEKC retention of the gemini surfactants. It should be noted that with their large positive coefficient a values, G1 and G2 were found to be stronger HB acceptors than anionic and most of the cationic surfactants studied in the literature. 相似文献
69.
Arslan M Masnovi J 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,64(3):711-716
Dimer model compounds of polyvinylanthracenes (1,n-di(9-anthryl)alkanes, when n=1-5) were synthesized to model the effects of distance and orientation between anthracene groups in polymeric systems. Charge transfer (CT) complexes of anthracene, 9-methylanthracene and 1,n-di(9-anthryl)alkanes with p-chloranil (p-CHL) have been investigated spectrophotometrically in dichloromethane. The colored products are measured spectrophotometrically at different wavelength depending on the electronic transition between donors and acceptor. The formation constants of the CT complexes were determined by the Benesi-Hildebrand equation. The thermodynamic parameters were calculated by Van't Hoff equation. Stochiometries of the complexes formed between donors and acceptor were defined by the Job's method of the continuous variation and found in 1:1 complexation with donor and acceptor at the maximum absorption bands. 相似文献
70.
Duymus H Arslan M Kucukislamoglu M Zengin M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,65(5):1120-1124
Charge transfer (CT) complexes of some non-steroidal anti-inflammatory drugs, naproxen and etodolac which are electron donors with some pi-acceptors, such as tetracyanoethylene (TCNE), 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ), p-chloranil (p-CHL), have been investigated spectrophotometrically in chloroform at 21 degrees C. The coloured products are measured spectrophotometrically at different wavelength depending on the electronic transition between donors and acceptors. Beer's law is obeyed and colours were produced in non-aqueous media. All complexes were stable at least 2 h except for etodolac with DDQ stable for 5 min. The equilibrium constants of the CT complexes were determined by the Benesi-Hildebrand equation. The thermodynamic parameters DeltaH, DeltaS, DeltaG degrees were calculated by Van't Hoff equation. Stochiometries of the complexes formed between donors and acceptors were defined by the Job's method of the continuous variation and found in 1:1 complexation with donor and acceptor at the maximum absorption bands in all cases. 相似文献