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111.
112.
A New Versatile Water‐Soluble Iniferter Platform for the Preparation of Molecularly Imprinted Nanoparticles by Photopolymerisation in Aqueous Media
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Dr. Paolo Bonomi Mira Daoud Attieh Dr. Carlo Gonzato Prof. Karsten Haupt 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(29):10150-10154
The multi‐step synthesis of a new water‐soluble dithiocarbamate iniferter platform for the preparation of nanoparticles and ‐gels in aqueous solvents by photoinduced living‐radical polymerisation is described herein. The water solubility of the dithiocarbamate iniferter was achieved by incorporating two unprotected glucose units into the iniferter structure by copper(I)‐catalysed azide–alkyne cycloaddition (“click chemistry”). Molecularly imprinted nanoparticles (MIPs) specific for 2,4‐dichlorophenoxyacetic acid and the corresponding non‐imprinted particles (NIPs) were prepared in pure water by using the prepared iniferter as photoinitiator. Radioligand binding tests confirmed a high imprinting factor, and the living character of the iniferter was demonstrated by re‐initiating a second photochemical polymerisation on the NIP nanoparticles in water by using ethylene glycol methacrylate phosphate. Our newly synthesised structure is a promising tool for iniferter‐mediated photopolymerisations in aqueous media for the preparation of biocompatible nanomaterials with high potential for biomedical applications in a bottom‐up fashion. 相似文献
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Yusuke Takahashi Shiro Kubuki Kazuhiko Akiyama Katalin Sinkó Ernő Kuzmann Zoltán Homonnay Mira Ristić Tetsuaki Nishida 《Hyperfine Interactions》2014,226(1-3):747-753
A relationship between methylene blue (MB) decomposition ability under visible light and local structure of xFe2O3·(100-x)SiO2 glass abbreviated as xFS prepared by sol-gel method was investigated by 57Fe-Mössbauer spectroscopy, X-ray diffractometry (XRD) and ultraviolet-visible light absorption spectroscopy (UV-Vis). Mössbauer spectra of xFS glass with x of 10, 30 and 50 annealed at 1000 °C for 3 h were mainly composed of a paramagnetic doublet due to fayalite (Fe2SiO4), and magnetic sextets due to magnetite (Fe3O4) or hematite (α-Fe2O3). The absorption area (A) of α-Fe2O3 gradually increased from 0.0 to 10.3 and 100 % with the increasing Fe2O3 content (x) of annealed xFS glass. A leaching test performed by 20 mL of MB aqueous solution and 40 mg of annealed 50FS glass showed that MB concentration decreased from 16.2 to 4.7 μmol L?1 after 2 h with the first order rate constant of 1.8 × 10?4 s?1. These results prove that annealed iron silicate glass containing α-Fe2O3 can decompose MB effectively under visible light irradiation. 相似文献
116.
Samer Aouad Amal Aoun Mira Skaf Madonna Labaki John El Nakat Bilal El Khoury Pierre Obeid Edmond Abi-Aad Antoine Aboukaïs 《Comptes Rendus Chimie》2013,16(10):868-871
The effects of CoxMgyAl2Oz mixed oxides composition and ruthenium addition on the oxidation of propylene and carbon black (CB) were investigated. Different reactive cobalt and ruthenium oxide species were formed following calcination at 600 °C. The addition of ruthenium was beneficial for the CB oxidation under “loose contact” conditions and for propylene oxidation when the cobalt content was intermediate to low. The calculated activation energy for CB oxidation was decreased from 151 kJ mol−1 for the uncatalyzed reaction to 111 kJ mol−1 over the best catalyst. 相似文献
117.
Mira Sundström Anna Pelander Verena Angerer Melanie Hutter Stefan Kneisel Ilkka Ojanperä 《Analytical and bioanalytical chemistry》2013,405(26):8463-8474
The continuing emergence of designer drugs imposes high demands on the scope and sensitivity of toxicological drug screening procedures. An ultra-high performance liquid chromatography/high-resolution time-of-flight mass spectrometry (UHPLC-HR-TOFMS) method was developed for screening and simultaneous confirmation of both designer drugs and other drugs of abuse in urine samples in a single run. The method covered selected synthetic cannabinoids and cathinones, amphetamines, natural cannabinoids, opioids, cocaine and other important drugs of abuse, together with their main urinary metabolites. The database consisted of 277 compounds with molecular formula and exact monoisotopic mass; retention time was included for 192 compounds, and primary and secondary qualifier ion exact mass for 191 and 95 compounds, respectively. Following a solid-phase extraction, separation was performed by UHPLC and mass analysis by HR-TOFMS. MS, and broad-band collision-induced dissociation data were acquired at m/z range 50–700. Compound identification was based on a reverse database search with acceptance criteria for retention time, precursor ion mass accuracy, isotopic pattern and abundance of qualifier ions. Mass resolving power in spiked urine samples was on average FWHM 23,500 and mass accuracy 0.3 mDa. The mean and median cut-off concentrations determined for 75 compounds were 4.2 and 1 ng/mL, respectively. The range of cut-off concentrations for synthetic cannabinoids was 0.2–60 ng/mL and for cathinones 0.7–15 ng/mL. The method proved to combine high sensitivity and a wide scope in a manner not previously reported in drugs of abuse screening. The method’s feasibility was demonstrated with 50 authentic urine samples. Figure
Extracted ion chromatograms of metabolites of synthetic cannabinoids and their fragments, including a new common metabolite: JWH-072-propanoic acid 相似文献
118.
Noelia Caballero-Casero Miraç Ocak Ümmüham Ocak Soledad Rubio 《Analytical and bioanalytical chemistry》2014,406(8):2179-2187
There is a need to monitor the consumption of curcuminoids, an EU-permitted natural colour in food, to ensure that acceptable daily intakes are not exceeded, especially by young children. This paper describes a sensitive method able to quantify low contents of curcumin (CUR), demethoxycurcumin (DMC) and bis-demethoxycurcumin (BDMC) in foodstuffs. The method was based on a single-step extraction by use of a supramolecular solvent (SUPRAS) made up of reverse aggregates of decanoic acid, and direct analysis of the extract by use of liquid chromatography–photodiode array (PDA) detection. The extraction involved the stirring of 200 mg foodstuff with 600 μL SUPRAS for 15 min. No cleanup or concentration of the extracts was required. Curcuminoid solubilisation occurred via dispersion and hydrogen bonding. The method was used for the determination of curcuminoids in different types of foodstuff (snack, gelatine, yoghurt, mayonnaise, butter, candy and fish products) that encompassed a wide range of protein, fat, carbohydrate, sugar and water contents (0.85–11.04, 0–81.11, 0.06–75, 0.06–79.48, and 10.08–85.10 g, respectively, in each 100 g of food). Method quantification limits for the foodstuffs analysed were in the ranges 2.9–7.7, 2.8–11.2 and 3.3–9.0 μg kg?1 for CUR, DMC and BDMC, respectively. The concentrations of curcuminoids detected in the foodstuffs and the recoveries obtained from fortified samples were in the ranges ND–284, ND–201 and ND–61.3 μg kg?1, and 82–106, 89–106 and 90–102 %, for CUR, DMC and BDMC, respectively. The relative standard deviations were in the range 2–7 %. This method enabled quick and simple microextraction of curcuminoids with minimal solvent consumption, while delivering accurate and precise data. Figure
? 相似文献
119.
M. P. Breijo C. Rey S. Castro M. Sánchez M. A. Señarís-Rodríguez J. Mira A. Fondado J. Rivas 《Ionics》1998,4(3-4):267-274
We have used three soft-chemistry methods for the efficient preparation of Ln1−xSrxCoO3 samples, adapting the combustion and the liquid-mix methods for the synthesis of the Ln = La and Gd compounds, respectively,
and the preparation of Nd1−xSrxCoO3 by the nitrate decomposition method.
We report the magnetic and electrical properties of these relatively small particle-size materials, specially in the case
of the Ln = La and Ln = Nd series (d≈0.2 μm and 0.5 μm, respectively), and we compare them to those displayed by the corresponding
compounds prepared at higher temperatures. The compounds here obtained are ferromagnetic for x≥0.15 when Ln = La and for x≥0.20
when Ln = Nd and Gd. Their resistivity decreases as the doping degree increases. And, very interestingly, for compositions
0.20<x≤0.45, when Ln = La, and for x=0.40, when Ln = Nd, they show M-I transitions as the temperature rises. These are very
sensitive to the application of electrical current and its polarity and the presence of magnetic fields, displaying peculiar
behaviors.
Paper presented at the 5th Euroconference on Solid State Ionics, Benalmádena, Spain, Sept. 13–20, 1998. 相似文献
120.
A Soibel SS Banerjee Y Myasoedov ML Rapparort E Zeldov S Ooi T Tamegai 《Pramana》2002,58(5-6):893-898
Using a novel differential magneto-optical imaging technique we investigate the phenomenon of vortex lattice melting in crystals
of Bi2Sr2CaCu2O8 (BSCCO). The images of melting reveal complex patterns in the formation and evolution of the vortex solid-liquid interface
with varying field (H)/temperature (T). We believe that the complex melting patterns are due to a random distribution of material disorder/inhomogeneities across
the sample, which create fluctuations in the local melting temperature or field value. To study the fluctuations in the local
melting temperature/field, we have constructed maps of the melting landscape T
m(H, r), viz., the melting temperature (T
m) at a given location (r) in the sample at a given field (H). A study of these melting landscapes reveals an unexpected feature: the melting landscape is not fixed, but changes rather
dramatically with varying field and temperature along the melting line. It is concluded that the changes in both the scale
and shape of the landscape result from the competing contributions of different types of quenched disorder which have opposite
effects on the local melting transition. 相似文献