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61.
《Solid State Ionics》2006,177(17-18):1495-1500
The structural and alkali ion insertion characteristics of sodium vanadium fluorophosphate, Na3V2(PO4)2F3 are presented. The material was prepared using a solid-state carbothermal reduction approach involving the precursors VPO4 and NaF. Electrochemical characterization of the Na3V2(PO4)2F3 phase in the potential range 3.0–4.6 V vs. Li, revealed a structured voltage response corresponding to the reversible cycling of two alkali ions per formula unit. The associated specific capacity was around 120 mAh/g, at an average discharge voltage of around 4.1 V vs. Li. The stability of the alkali ion insertion reactions was confirmed by long term cycling experiments, which demonstrated low capacity fade over the initial 220 cycles. Voltage excursions to 5 V vs. Li suggest that all three Na ions may be successfully extracted from the fluorophosphate phase, although this process is likely accompanied by some concurrent structural degradation.  相似文献   
62.
High quality arrays of Ln(OH)3 (Ln = La, Nd) nanowires have been successfully fabricated for the first time by an electrochemical process using anodic alumina membrane templates. A physico-chemical characterisation of electrodeposited hydroxides has been carried out by different techniques (XRD, SEM and EDX). The results show that the synthesized nanostructures are crystalline, dense, continuous, well aligned, and with high aspect ratio, suggesting further development of possible applications in the lanthanide family species.  相似文献   
63.
《Solid State Ionics》2006,177(11-12):1099-1104
Iron oxychloride has been lithiated by the reaction with n-butyllithium and thereafter exposed to air. Lithium intercalation increases several orders of magnitude of the electrical conductivity of the pristine material although the intercalate remains a semiconductor. This phase, after being exposed to atmospheric humidity becomes an ionic conductor, with a conductivity comparable to that of some molten salts, and does not show electronic conduction in the whole range of temperatures of measurement (150–300 K), a strong non-Arrhenius behaviour being observed. Impedance spectroscopy and NMR techniques, among others, have been used to follow this behaviour.  相似文献   
64.
65.
《Tetrahedron letters》2019,60(20):1363-1369
A Fe3+-specific probe (N-TC) based on Rhodamine B was designed and synthesized. N-TC has a good spectral response to Fe3+ in the EtOH/H2O solution (1:1, v/v, HEPES, 0.5 mM, pH = 7.38) with low detection limits and high binding constants. N-TC displays the reversible “turn-off-on” fluorescence response with 1:1 binding stoichiometry. It is further proven to be practical in sensitively monitoring trace Fe3+ in environmental water specimens. Biological experiments demonstrated that N-TC can be respectively used as a probe for detection of Fe3+ in living cells, animals and plant tissues.  相似文献   
66.
Nowadays, the design and development of novel phosphorescent iridium(III) complexes for various optoelectronic applications is a well-recognized area of research. The fascinating photophysical properties of iridium(III) compounds are strongly influenced by the spin-orbit coupling exerted by the iridium(III) core, usually resulting in intense emissions with short excited-state lifetimes, which can be precisely controlled with the aid of molecular engineering of the chelating ligand. This review focuses on the recent developments and state of the art knowledge on phosphorescent iridium(III) compounds, especially on heteroleptic complexes derived from 2,3′-bipyridine class of cyclometalating and ancillary ligands, highlighting the excited state phenomenon behind their emission behavior.  相似文献   
67.
《中国化学快报》2023,34(8):108122
By considering the exceptional properties of supramolecular, noble metals (NM) and magnetic nanoparticles (NPs), we successfully synthesized a novel magnetic, metals and supramolecular composite. Briefly, the Fe3O4@SiO2 core-shell spheres were first modified with gold (Au) and palladium (Pd) NPs and then with mono-6-thio-β-cyclodextrin (SH-β-CD). The synthesized Fe3O4@SiO2-Au-Pd@SH-β-CD nanocomposite shows a good magnetic response (42.3 emu/g). The nanocomposite showed good performance for the reductive degradation of rhodamine B (RhB) and 4-nitrophenol (4-NP). The calculated rate constant (k) values for the reduction of 4-NP and RhB were 0.062± 0.02 s−1 and 0.027± 0.01 s−1, respectively. The high catalytical performance was supposed to be due to the host-guest interaction of β-CD and also due to the NM synergic effect. The nanocomposite structural and chemical morphology was investigated by various spectroscopic techniques. Furthermore, the catalyst was recycled six times and it maintains morphology, chemical nature, and high magnetic behavior, as demonstrated by FTIR and TEM analysis of the recycled catalyst. These results demonstrate a very efficient, cost-effective, and recyclable catalyst in the field of catalysis technology development.  相似文献   
68.
Photothermal therapy(PTT) induces thermoresistance through cellular heat shock response, which impairs the therapeutic efficacy of the PTT. To resolve this problem, we developed a photothermal theranostics(denoted as PMH), which integrated the photothermal conversion agent of PdMo bimetallene with histone deacetylase 6(HDAC6) selected inhibitor(ACY-1215), showing the synergistic antitumor effect both in vitro and in vivo. Mechanistically, under the photoacoustic imaging(PA) navigation, the relea...  相似文献   
69.
The performance of aqueous Zn ion batteries (AZIBs) is highly dependent on inner Helmholtz plane (IHP) chemistry. Notorious parasitic reactions containing hydrogen evolution reactions (HER) and Zn dendrites both originate from abundant free H2O and random Zn deposition inside active IHP. Here, we report a universal high donor number (DN) additive pyridine (Py) with only 1 vol. % addition (Py-to-H2O volume ratio), for regulating molecule distribution inside IHP. Density functional theory (DFT) calculations and molecular dynamics (MD) simulation verify that incorporated Py additive could tailor Zn2+ solvation sheath and exclude H2O molecules from IHP effectively, which is in favor of preventing H2O decomposition. Consequently, even at extreme conditions such as high depth of discharge (DOD) of 80 %, the symmetric cell based on Py additive can sustain approximately 500 h long-term stability. This efficient strategy with high DN additives furnishes a promising direction for designing novel electrolytes and promoting the practical application of AZIBs, despite inevitably introducing trace organic additives.  相似文献   
70.
Fe3O4/hydroxyapatite/graphene quantum dots (Fe3O4/HAP/GQDs) nanocomposite was synthesized and used as a novel magnetic adsorbent. This nanocomposite was characterized using scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, and magnetization property. The Fe3O4/HAP/GQDs was applied to pre-concentrate copper residues in Thai food ingredients (so-called “Tom Yum Kung”) prior to determination by inductively coupled plasma-atomic emission spectrometry. Based on ultrasound-assisted extraction optimization, various parameters affecting the magnetic solid-phase extraction, such as solution pH, amount of magnetic nanoparticles, adsorption and desorption time, and type of elution solvent and its concentration were evaluated. Under optimal conditions, the linear range was 0.05–1500 ng mL−1 (R2 > 0.999), limit of detection was 0.58 ng mL−1, and limit of quantification was 1.94 ng mL−1. The precision, expressed as the relative standard deviation of the calibration curve slope (n = 5), for intra-day and inter-day analyses was 0.87% and 4.47%, respectively. The recovery study of Cu for real samples was ranged between 83.5% and 104.8%. This approach gave the enrichment factor of 39.2, which guarantees trace analysis of Cu residues. Therefore, Fe3O4/HAP/GQDs can be a potential and suitable candidate for the pre-concentration and separation of Cu from food samples. It can easily be reused after treatment with deionized water.  相似文献   
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