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101.
We synthesized a tridentate Schiff base ligand, 6‐(((2‐hydroxyphenyl)amino)methylene)‐2‐methoxycyclohexa‐2,4‐dienone [H2L], as well as its Mo(VI) complex [MoO2(L)(DMSO)], and then characterized them completely using elemental analysis, FT‐IR, UV–Vis and 1HNMR spectroscopy techniques. X‐ray single crystal diffraction method was used for the determination of the structure of the synthesized ligand and complex. All other spectroscopic techniques performed, confirmed that [MoO2(L)(DMSO)]had an octahedral geometry around the Mo(VI) central ion coordinated by the donor atoms of the deprotonated ligand, two oxido groups and one oxygen atom of DMSO molecule. Hybrid functional B3LYP with DGDZVP as basis set was applied for DFT calculations of the compounds in their ground state. The MEP, Mulliken, HOMO‐LUMO energy gap and thermodynamic properties of the compounds were also theoretically predicted. In‐vitro antimicrobial studies on the synthesized compounds indicated the great antibacterial activities of the Mo(VI) complex against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Bacillus cereus bacteria.  相似文献   
102.
Palladium(0) as one of the vital transition metals, is employed in numerous industries, such as drug synthesis, aerospace high-tech field and automobile industry. When the Pd(0) enter into the body, it will bind with thiol-containing amino acids, DNA, RNA, and other biomolecules damaging to human health. Thus, developing a novel tool for monitoring and imaging of Pd(0) in vivo is very urgent. In the work, based on a intramolecular charge transfer (ICT) mechanism a two-photon fluorescent probe NIPd had been designed and synthesized for the recognition Pd(0). In vitro experiments data displayed that probe NIPd exhibited a 13-fold fluorescent increase for Pd(0) in 30 min in the aqueous solution with a detection limit of 16 nmol/L. It also showed the outstanding selectivity and antijamming performance. More importantly, NIPd could be served as a two-photon fluorescent probe for real-time monitoring Pd(0) in living cells and mice.  相似文献   
103.
The androgen receptor (AR) is a pivotal target for the treatment of prostate cancer (PC) even when the disease progresses toward androgen-independent or castration-resistant forms. In this study, a series of 15 bicalutamide analogues (sulfide, deshydroxy, sulfone, and O-acetylated) were prepared and their antiproliferative activity evaluated against four different human prostate cancer cell lines (22Rv1, DU-145, LNCaP, and VCap). Bicalutamide and enzalutamide were used as positive controls. Seven of these compounds displayed remarkable enhancement in anticancer activity across the four PC cell lines. The deshydroxy analogue (16) was the most active compound with IC50 = 6.59–10.86 µM. Molecular modeling offers a plausible explanation of the higher activity of the sulfide analogues compared to their sulfone counterparts.  相似文献   
104.
Research on Chemical Intermediates - New series of pyrimidinone-5-carbonitriles 3a–i, 4a–e, 5a–c, 6 and 7 have been synthesized and explored for their activities as anticancer,...  相似文献   
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This work reports synthesis and characterization of heterocyclic functionalized polymers, poly(triazole-etherimidazole)s(PTAEI), from a dialkyne-terminated compound, 3-(4,5-bis(4-(propargyloxy)phenyl)-1H-imidazol-2-yl)-9-ethyl-9H-carbazole, by using click reaction. PTAEIs were characterized and their properties such as solubility, thermal, mechanical, photophysical and metal ions adsorption were investigated. These polymers had weight average molar masses(Mw) in the range of 19100-26700 g/mol, exhibited excellent solubility in polar aprotic solvents and formed low-colored flexible thin films by solution casting method. They exhibited good thermal stability with glass transition temperatures(Tg) between 160 °C and 211 °C and 10% weight loss temperatures(T10%) in the range of 308-426 °C. Nanocomposites of PTAEIs with epoxide-terminated Fe3O4 showed that strong interfacial interaction between inorganic particles and the polymer matrix contributed to the enhanced thermal and mechanical properties. The photoluminescence intensity of the PTAEIs increased and the spectra red shifted with increasing Fe3O4 content. The PTAEIs and nanocomposites were tested for their extraction capability of metal ions from aqueous solutions either individually or in the mixture.  相似文献   
108.
The dependence on ionic strength of protonation of nitrilotriacetic acid and its complexation with W(VI) is reported in sodium perchlorate, sodium nitrate and sodium chloride solutions as background salts. The measurements have been performed at 25°C and various ionic strengths in the range 0.1–1.0 mol dm−3, using a combination of potentiometric and spectrophotometric techniques. The overall analysis of the present and the previous data dealing with the determination of stability constants at different ionic strengths allowed us to obtain a general equation, by which a formation constant determined at a fixed ionic strength can be calculated, with a good approximation, at another ionic strength, if 0.1 ≤ ionic strength ≤ 1.0 mol dm−3 sodium perchlorate, sodium nitrate or sodium chloride.  相似文献   
109.
The effects of Ag-doping on the physico-chemical, spectral, surface, and catalytic properties of the FeMgO system with various Fe2O3 loadings were investigated. The dopant (Ag) molar ratio varied between 0.01 % and 0.05 %. The techniques employed for characterisation of catalysts were TG/DTG, XRD, ESR, N2 adsorption at ?196°C, and catalytic decomposition of H2O2 at 25?C35°C. The results obtained revealed that the investigated catalysts consisted of nanosized MgO as the major phase, apart from the MgFe2O4 and/or Fe3O4 phases. ESR result of the FeMgO system revealed the presence of paramagnetic species as a result of Ag-doping. The textural properties including SBET, porosity and St were modified by Ag-doping. The doping process with Ag-species improved the catalytic activity of the FeMgO system. Increasing the calcination temperature from 400°C to 800°C increased the catalytic activity (k*30 °C) of 0.05 AgFeMgO in H2O2 decomposition by 21.2 times.  相似文献   
110.
Gold nanoparticles (GNs) could be efficiently immobilized on binary mixed self-assembled monolayers (SAMs) on a gold surface composed of 1,6-hexanedithiol and 1-octanethiol (nano-Au/SAMs gold electrode). This GN chemically modified electrode was used for electrochemical determination of ascorbic acid (AA) and dopamine (DA) in aqueous media. The result showed that the GN-modified electrode could clearly resolve the oxidation peaks of AA and DA, with a peak-to-peak separation (∆E p) of 110 mV enabling determination of AA and DA in the presence of each other. The linear analytical curves were obtained in the ranges of 0.3–1.4 mM for AA and 0.2–1.2 mM for DA concentrations using differential pulse voltammetry. The detection limits (3σ) were 9.0 × 10−5 M for AA and 9.0 × 10−5 M for DA.  相似文献   
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