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871.
The new age drugs are nanoparticles of metals, which can combat conditions like wounds and fight human pathogens like bacteria. The aim of the experiment was preparation, characterization, and assessment of cytotoxicity, antioxidant, cutaneous wound healing, antibacterial, and antifungal potentials of gold nanoparticles using the aqueous extract of Falcaria vulgaris leaves (AuNPs@F. vulgaris) under in vitro and in vivo condition. These nanoparticles were characterized by FT‐IR, UV, XRD, FE‐SEM, TEM, and AFM. The synthesized AuNPs@F. vulgaris had great cell viability dose‐dependently (Investigating the effect of the nanoparticles on HUVEC cell line) and indicated these nanoparticles were nontoxic. DPPH free radical scavenging test was done to evaluate the antioxidant potentials, which showed similar antioxidant potentials for AuNPs@F. vulgaris and butylated hydroxytoluene. In part of cutaneous wound healing effect of F. vulgaris, after creating the cutaneous wound, the rats were randomly divided into six groups: untreated control, treatment with Eucerin basal ointment, treatment with 3% tetracycline ointment, treatment with 0.2% HAuCl4 × H2O ointment, treatment with 0.2% F. vulgaris ointment, and treatment with 0.2% AuNPs@F. vulgaris ointment. These groups were treated for 10 days. Use of AuNPs@F. vulgaris ointment in the treatment groups substantially decreased (p ≤ 0.01) the wound area, total cells, neutrophil, and lymphocyte and remarkably raised (p ≤ 0.01) the wound contracture, hydroxyl proline, hexuronic acid, fibrocyte, and fibrocytes/fibroblast rate compared to other groups. In antimicrobial part, MIC, MBC, and MFC were specified by macro‐broth dilution assay. AuNPs@F. vulgaris revealed higher antibacterial and antifungal properties than many standard antibiotics (p ≤ 0.01). Also, AuNPs@F. vulgaris prevented the growth of all bacteria at 2‐8 mg/ml concentrations and removed them at 2‐16 mg/ml concentrations (p ≤ 0.01). In case of antifungal potentials of AuNPs@F. vulgaris, they inhibited the growth of all fungi at 2‐4 mg/ml concentrations and destroyed them at 2‐8 mg/ml concentrations (p ≤ 0.01). In conclusion, synthesized AuNPs@F. vulgaris revealed non‐cytotoxicity, antioxidant, cutaneous wound healing, antibacterial, and antifungal activities.  相似文献   
872.
The aim of this study was to develop a new method for the determination of benzene, toluene, ethylbenzene and xylene isomers (BTEXs) in urine samples. In this method, MIL-100(Fe)@Fe3O4@SiO2 metal–organic framework was synthesized, characterized and packed inside a needle trap device (NTD) as a sorbent for headspace extraction of unmetabolized BTEXs from urine samples followed by gas chromatography (GC) analysis. The GC device was equipped with a flame ionization detector (FID). The results showed that the optimal extraction time, extraction temperature and salt content were 60 min, 30°C and 5%, respectively. Also, the optimal desorption time and temperature were determined to be 1 min and 250°C, respectively. The limits of detection and quantification of the analytes of interest were in the ranges 0.0001–0.0005 and 0.0003–0.0014 μg ml−1, respectively. The intra- and inter-day repeatability were <7.6%. The accuracy of the measurements in urine samples was in the range 7.1–11.4%. The results also demonstrated that the proposed NTD offered various advantages such as having high sensitivity and being inexpensive, reusable, user friendly, environmentally friendly and compatible for use with the GC device. Therefore, it can be efficiently used as a MIL–NTD for the extraction and analysis of unmetabolized BTEXs from urine samples.  相似文献   
873.
Recently, the development of carbon nanocomposites composed of carbon nanotubes and metal nanoparticles has attracted many interests because of their large potential for technological applications such as catalysts, sensors, biomedicine, and disinfection. In the present study, we described a simple chemistry method to synthesize multi-walled carbon nanotubes (MWCNTs) decorated with silver nanoparticles (Ag-NPs). Also, we investigated the antioxidant and anti-acute leukemia activities against acute myeloid leukemia and acute T cell leukemia cell lines. Ag NPs-MWCNTs were characterized and analyzed using common nanotechnology techniques including transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), field emission-scanning electron microscopy (FE-SEM) and elemental mapping analysis. Also, 2,2-diphenyl-1-picrylhydrazyl (DPPH) test was performed to assess the antioxidant capacities of AgNO3, MWCNTs, and Ag NPs-MWCNTs. It revealed similar antioxidant potentials for Ag NPs-MWCNTs and butylated hydroxytoluene. In MTT assay, Ag NPs-MWCNTs had very low cell viability (very high anti-acute leukemia properties) dose-dependently against 32D-FLT3-ITD (Acute myeloid leukemia cell line), Human HL-60/vcr (Acute myeloid leukemia cell line), Jurkat, Clone E6–1 (Acute T cell leukemia cell line), and J.RT3-T3.5 (Acute T cell leukemia cell line) without any cytotoxicity on human umbilical vein endothelial cell line (HUVEC; Normal cell line). In conclusion, the synthesized Ag NPs-MWCNTs revealed excellent antioxidant and cytotoxicity activities against acute myeloid leukemia and acute T cell leukemia cell lines in a dose depended manner. After confirming in the in vivo and clinical trials, these nanoparticles can be administrated in humans for the treatment of acute leukemia especially acute myeloid leukemia and acute T cell leukemia.  相似文献   
874.
A series of new N-acetyl/thioacetyl-(E)-stilbene benzenesulfonamide derivatives were synthesized regioselectively in moderate to high yields by following a convenient, three-step procedure. The procedure consists of the direct oxidative conversion of a thiol compound to the corresponding sulfonyl chloride using TMSCl/KNO3, followed by a room temperature reaction in a one-pot transformation of the resultant sulfonyl chloride into N-acetyl/thioacetyl sulfonamide, which undergoes a further Pd-catalyzed coupling reaction, giving rise to the stilbene compounds reported for the first time.  相似文献   
875.
Ethylene diamine functionalized MIL‐101(Cr) was established to be an efficient organocatalyst for single‐pot synthesis of polyhydroquinolines via four‐component condensation reaction between aldehydes, dimedone, β‐ketoecters and ammonium acetate in aqueous medium. Ethylene diamine of the parent open metal site MIL‐101(Cr) has been carried out through a post‐synthetic modification (PSM) technique. Efficient transformation, mild condition, easy product isolation and the potential high recycbility of the organocatalyst are the key feature of this protocol.  相似文献   
876.
Poly(4-vinylpyridinium tribromide) was found to be an efficient oxidizing polymer for the chemoselective oxidation of a wide range of alcohols into aldehydes and ketones. In addition it was used for the oxidative deprotection of trimethylsilyl ethers into alcohols or carbonyl compounds depending on the structure of trimethylsilyl ether.  相似文献   
877.
878.
Fe3O4 nanoparticles were coated with aminopropyltriethoxysilane and subsequently reacted with isatin to obtain imine‐bonded Fe3O4 nanoparticles. The addition of ZrOCl2?8H2O or CuCl2 led to the formation of complexes of Zr(IV)/isatin@Fe3O4 or Cu (II)/isatin@Fe3O4 as new magnetically separable catalysts. The synthesized catalysts were characterized using various techniques. These catalysts are shown to be efficient for chemo‐selective oxidation of sulfides to sulfoxides using hydrogen peroxide as oxidative agent. This system has many advantages, such as excellent level of reusability of magnetic catalysts, high yields, simplicity of separation of catalysts using an external magnet, environmental benignity and ease of handling. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
879.
880.
A new Cu(II) immobilized on hyperbranched polyglycerol (HPG) functionalized graphene oxide catalyst was prepared and characterized by FT-IR, TGA, FE-SEM, XRD, and ICP-OES techniques. This catalyst was used efficiently for the preparation of aminonaphthoquinones via one-pot three-component condensation reaction under solvent-free conditions. The catalyst could be easily recovered and reusable several times without a significant loss of activity, which make this method attractive and in a close agreement with green chemistry.  相似文献   
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