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61.
Allumines A and B ( 1 and 2 , resp.), two new steroidal alkaloids, and a new cyclopentene derivative, 3 , were isolated from the CHCl3‐soluble fraction of the whole plant of Allium victorialis. Their structures were elucidated by spectroscopic techniques, including 1D‐ and 2D‐NMR spectroscopy.  相似文献   
62.
The ZnO and gallium-doped ZnO nanoparticles (NPs) were synthesized by simple chemical method and used for the fabrication of p-polyaniline/n-ZnO heterostructures devices in which polyaniline was deposited by plasma-enhanced polymerization. The increment in the crystallite sizes of gallium doped ZnO nanoparticles from ~21.85 nm to ~32.39 nm indicated the incorporation of gallium ion into the ZnO nanoparticles. The surface and structural studies investigated the participation of protonated N atom for the bond formation between polyaniline and gallium-ZnO through partial hydrogen bonding. Compared to a Pt/polyaniline/ZnO diode, the fabricated Pt/polyaniline/gallium-ZnO heterostructure diode exhibited good rectifying behavior with Current–Voltage characteristics of improved saturation current, low ideality factor, and a high barrier height might due to the efficient charge conduction via gallium ion at the junction of the polyaniline/gallium doped-ZnO interface.
Figure
(a) Schematic illustration and (b) I-V characteristics of Pt/PANI/Ga-ZnO heterostructure device. The heterostructure device is obtained by a top Pt layer on PECVD deposited PANI/Ga-ZnO electrodes. The fabricated Pt/PANI/Ga-ZnO heterostructure device displays non-linear and rectifying behavior of I–V curve due to the existence of Schottky barrier via a Schottky contact at the interfaces of Pt layer and PANI/Ga-ZnO thin film layer.  相似文献   
63.
The polyaniline/zinc oxide (PANI/ZnO) nanocomposites were prepared by in situ polymerization of aniline monomer with ZnO nanomaterials and applied as a photocatalyst for the degradation of methylene blue (MB) dye. The morphological observations elicited the agglomerations of PANI sheets which occurred due to the interaction between PANI and ZnO nanomaterials in PANI/ZnO nanocomposites. As compared to pristine PANI, the UV–vis spectra exhibited that the absorption peak of ππ* transitions considerably shifted to higher wavelength at 360 nm from 325 nm in the nanocomposites. The photocatalytic activity results indicated the substantial degradation of MB dye by ~76% over the surface of PANI/ZnO nanocomposite catalyst under light illumination. The PANI/ZnO nanocomposites showed three times higher photocatalytic activity to MB dye degradation compared to pristine PANI might due to high photogenerated electron (ē)–hole (h+) pairs charge separation.  相似文献   
64.
This paper is devoted to find the Locally Rotationally Symmetric (LRS) vacuum solutions in the context of f(R) theory of gravity. Actually, we have considered the three metrics representing the whole family of LRS spacetimes and solved the field equations by using metric approach as well as the assumption of constant scalar curvature. It is mention here that R may be zero or non-zero. In all we found 10 different solutions.  相似文献   
65.
Bloodstream infection with methicillin‐resistant Staphylococcus aureus (MRSA) and other drug‐resistant bacteria kill several million people in the world every year. Detection of drug‐resistant bacteria in the blood stream is clinically important to save lives. Driven by this need, multifunctional theranostic nanoplatforms have been developed for simultaneous targeted imaging and multimodal photodestruction of MRSA in a whole‐blood sample. Experimental data for the whole‐blood sample spiked with MRSA show that the theranostic nanoplatform can be used for fluorescence imaging after magnetic separation even in a 10?5:1 ratio. A targeted photodynamic and photothermal combined treatment shows that the multimodal treatment regime can dramatically enhance the possibility of destroying MRSA in vitro. Therefore, our developed theranostic nanoplatform have a great potential as a fluorescent marker and as a light absorber for combined therapy in clinical settings. The possible mechanisms and operating principles are discussed for targeted imaging and combined therapeutic actions using theranostic nanoplatform.  相似文献   
66.
In the present study, naphthyl acetohydrazide (HL) ligand was prepared and used for the synthesis of new six amorphous transition metal (Co(II), Ni(II), Cu(II), Zn(II), Pb(II), Cd(II)) complexes. All the compounds were characterized by elemental analysis, UV-vis, FT-IR, 1H- and 13C-NMR, and Matrix-Assisted Laser Desorption Ionization (MALDI). The solubilization study was carried out by estimating the interaction between the metal complexes with surfactants viz. sodium stearate (SS) and Cetyltrimethylammonium bromide (CTAB). UV-Visible spectroscopy was employed to determine partitioning and binding parameters, whereas electrical conductivity measurements were employed to estimate critical micellar concentration (CMC), the extent of dissociation, and free energy of micellization. The CT-DNA interaction of synthesized compounds with DNA represents the major groove binding. The synthesized ligand and metal complexes were also tested against bacterial and fungal strains and it has been observed that Cu(II) complex is active against all the strains except Candida albicans, while Cd(II) complex is active against all bacterial and fungal strains except Pseudomonas. Among all compounds, only the Pd(II) complex shows reasonable activity against cervical cancer HeLa cell lines, representing 97% inhibition.  相似文献   
67.
Pepped up polymers : The synthesis and properties of novel chiral cyclic peptides designed to complex with suitable polymers through hydrogen bonding are described. A substituted cyclic peptide self‐assembles into supramolecular nanotubes and develops noncovalent interactions with poly(vinyl alcohol) (PVA) by means of its carboxyl side chains.

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68.
This papers describes the in vitro interaction of copper(II) acetylsalicylate and copper(II) salicylate with genomic DNA isolated from human blood. The two drug substances were found to bind to DNA after incubation with whole blood over night. Bonding was confirmed by detection of separated DNA electrophoresis bands for copper, copper(II) acetylsalicylate, copper(II) salicylate, acetylsalicylic acid and salicylic acid. Drug–DNA interactions were observed during electrophoresis in the form of fragmentation by formation of two bands when compared to controls. Gel permeation chromatography parameters also confirmed the occurrence of fragmentation. The use of gel permeation chromatography parameters as a measure of fragmentation of DNA is discussed. The fragmentation of genomic DNA after incubation with copper(II) acetylsalicylate and copper(II) salicylate suggested that these drug substances might be responsible for cytotoxicity in vivo.  相似文献   
69.
To find out effective anticancer compounds we synthesized (130) derivatives of 4-isopropylbenzoylhydrazone and evaluated for anticancer potential. The compounds 3, 9, 12, 23, 26 and 28 showed better activities ranging (0.39–1.1 µg/ml) than the standard (1.53 ± 0.01 µg/ml). In line with this, compounds 2, 6, 24, 25 and 29 exhibited better activities compared to the second standard (5FU 4.60 ± 0.01 µg/ml). The best molecular docked complex between the BRCA1 structure and the 130 derivatives were analyzed based on the Glide docked score and binding orientation for both the SP and XP mode. The 2D-QSAR analysis reflected a significant correlation between the experimental and the predicted biological activities. The above-mentioned compounds were also assessed by various spectroscopic techniques.  相似文献   
70.

The present study aimed to synthesize poly(acrylic acid) hydrogel embedded with magnetic cobalt (Co) nanoparticles and to investigate their potential in adsorption and catalysis. The hydrogel was prepared by facile free radical polymerization reaction and Co nanoparticles were fabricated within hydrogel by reducing Co (II) ions using NaBH4 as reducing agent. Co nanoparticles within hydrogel system imparted magnetic properties to the resulting composite gel and also increased the adsorption capacity. The swelling study of hydrogel was carried out by gravimetric analysis. Different functional groups were identified by Fourier Transform Infrared Spectroscopy and Transmission Electron Microscopy analysis was done to investigate dispersion of Co nanoparticles in hydrogel. The bare hydrogel along with Co nanoparticles loaded gel were tested as adsorbent systems for the removal of a cationic dye (methylene blue) from aqueous solution. 95% removal of methylene blue was achieved with a highest adsorption capacity of 836.5 mg/g of adsorbent. The famous adsorption isotherms were used to evaluate adsorption data. Results showed that Freundlich isotherm model was followed with R2 value of 0.95. The hydrogel was also used for catalytic reduction in a toxic pollutant, i.e., 4-nitrophenol. Experimental data for 4-nitrophenol reduction followed pseudo first order kinetics model. Activation energy and apparent rate constant were calculated as 9.24 kJ/mol and 0.24 min−1, respectively. Recycling of the magnetic poly(acrylic acid) hydrogel fabricated with Cobalt nanoparticles was carried out for four consecutive cycles and no significant loss in catalytic activity was observed.

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