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31.
The title compound is synthesized by reaction of FeCl3·6H2O with liquid NH3 and characterized by single crystal XRD. 相似文献
32.
Jo?l?Coulon Ilan?Thouvenin Fadi?Aldeek Lavinia?Balan Rapha?l?Schneider 《Journal of fluorescence》2010,20(2):591-597
Highly fluorescent CdTe quantum dots (QDs) stabilized by thioglycolic acid (TGA) were prepared by an aqueous solution approach
and used as fluorescent labels in detecting yeast cells. Sugars (mannose, galactose or glucose) were adsorbed on CdTe@TGA
QDs and the interaction of these nanoparticles with yeast cells was studied by fluorescence microscopy. Results obtained demonstrate
that galactose and mannose functionalized QDs associate respectively with Kluyveromyces bulgaricus and Saccharomyces cerevisiae yeast strains due to saccharide/lectin specific recognition. Glucose-functionalized CdTe QDs, which are not recognized by
cell lectins, preferentially localize in the bud scars of S. cerevisiae. 相似文献
33.
Marinescu L Mølbach M Rousseau C Bols M 《Journal of the American Chemical Society》2005,127(50):17578-17579
6A,6D-Di-O-(propan-2-on-1,3-diyl) alpha-cyclodextrin-6A,6D-dicarboxylate (2alpha) and 6A,6D-di-O-(propan-2-on-1,3-diyl) beta-cyclodextrin-6A,6D-dicarboxylate (2beta) were found to catalyze the oxidation of aromatic amines in the presence of hydrogen peroxide. The products were the corresponding nitro compounds or in some cases azo-, azoxy-, or other dimerization products. The catalysis was found to follow enzyme kinetics giving a rate increase (kcat/kuncat) of up to 1100 in the best case. 相似文献
34.
Adriana POPA Corneliu-Mircea DAVIDESCU Smaranda ILIESCU Gheorghe ILIA Gheorghe DEHELEAN Lavinia MACARIE Radu TRIF Rumanian Academy Institute of Chemistry M. Viteazul Str. Timisoara Roumania. "Politehnica" University Faculty 《Chinese Journal of Reactive Polymers》2000,(2)
1.INTRODUCTIONThesynthesisofpolymer-supported"onium"salts(ammoniumandphosphonium)(1~5(wasdiscussedindetailduetothewidefieldofutilizationas:polarstationaryphasesforanionchromatography(6(,polymericreagentsfortrans-quaternizationreactions(7,8(,phase-transfercatalysts(9~13(andpolycationicbiocides(14~17(.Manychemicalmaterialssuchasozone,liquidchlorine,sodiumhydrochloride,s.a.,havebeenlargelyusedtosterilizeairandwater.Suchmaterialsrequirespecialequipmentandcarelessusemaycauseenvironmentalpolluti… 相似文献
35.
TMSN3 and PhI(OAc)2 were found to promote high-yield azide substitution of ethers, aldehydes and benzal acetals. The reaction is fast and occurs at zero to ambient temperature in acetonitrile. However, it is essential for the reaction that TMSN3 is added subsequent to the mixture of PhI(OAc)2 and the substrate. A primary deuterium kinetic isotope effect was found for the azidonation of benzyl ethers both with TMSN3-PhI(OAc)2 and with IN3. Also a Hammett free energy relationship study of this reaction showed good correlation with sigma+ constants giving with rho-values of -0.47 for TMSN3-PhI(OAc)2 and -0.39 for IN3. On this basis a radical mechanism of the reaction was proposed. 相似文献
36.
Carlo F. Morelli Arianna Fornili Lavinia Durì Paolo Manitto 《Tetrahedron letters》2005,46(11):1837-1840
The Cl2AlH-mediated ring-opening of 2-substituted cis-4-methyl-5-trifluoromethyl-1,3-dioxolanes was found to occur with regioselective cleavage of the O1-C2 bond by attack of the aluminum hydride from the direction anti to the departing oxygen. This stereochemical outcome, which appears to be unprecedented in the reductive cleavage of chiral acetals by aluminum reagents, is interpreted on the basis of theoretical calculations. 相似文献
37.
Aliphatic and aromatic aldehydes can be converted to acyl azides by treatment with iodine azide at 0-25 degrees C. If the reaction is performed at reflux Curtius rearrangement occurs and carbamoyl azides are obtained in 70-97% yield from the aldehyde. The reaction was shown to have a radical mechanism. 相似文献
38.
[Ge2]4− Dumbbells with Very Short Ge−Ge Distances in the Zintl Phase Li3NaGe2: A Solid‐State Equivalent to Molecular O2 下载免费PDF全文
Lavinia M. Scherf Prof. Dr. Antti J. Karttunen Dr. Oliver Pecher Dr. Pieter C. M. M. Magusin Prof. Dr. Clare P. Grey Prof. Dr. Thomas F. Fässler 《Angewandte Chemie (International ed. in English)》2016,55(3):1075-1079
The novel ternary Zintl phase Li3NaGe2 comprises alkali‐metal cations and [Ge2]4? dumbbells. The diatomic [Ge2]4? unit is characterized by the shortest Ge?Ge distance (2.390(1) Å) ever observed in a Zintl phase and thus represents the first Ge=Ge double bond under such conditions, as also suggested by the (8?N) rule. Raman measurements support these findings. The multiple‐bond character is confirmed by electronic‐structure calculations, and an upfield 6Li NMR shift of ?10.0 ppm, which was assigned to the Li cations surrounded by the π systems of three Ge dumbbells, further underlines this interpretation. For the unperturbed, ligand‐free dumbbell in Li3NaGe2, the π‐ bonding py and pz orbitals are degenerate as in molecular oxygen, which has singly occupied orbitals. The partially filled π‐type bands of the neat solid Li3NaGe2 cross the Fermi level, resulting in metallic properties. Li3NaGe2 was synthesized from the elements as well as from binary reactants and subsequently characterized crystallographically. 相似文献
39.
The role of segregation in the polarized emission from polyfluorene embedded in a liquid crystal 下载免费PDF全文
Lavinia Ghirardini Tersilla Virgili Serena Bolis Jeroen Beeckman Pascal Kockaert Marco Finazzi Michele Celebrano 《Journal of Polymer Science.Polymer Physics》2016,54(16):1558-1563
Polyfluorene (PFO) embedded in a nematic liquid crystal (LC) matrix is investigated. For low PFO weight contents, a homogeneous dispersion is obtained which displays a strong fluorescence anisotropy along the LC director, indicating a significant alignment of the polymeric chains along this direction. Besides, for relatively high PFO weight contents, phase separation takes place. Under these conditions, the sample is composed of micrometer‐sized domains, where the two species are in solution, enclosed by segregated polymeric boundaries. By polarized‐photoluminescence imaging and spectroscopy, it is found that most of the light emission originates from these boundaries and gets strongly pinned along their orientation. Since boundaries are mainly oriented orthogonal to the LC chains, this morphological alignment results in a system in which the orientation of the polarization emission can be predicted and possibly controlled. Conversely, in the homogeneous sample one can obtain a homogeneous emission polarization by controlling the alignment of the LC. These features are potentially relevant for the development of flexible polarization‐sensitive optoelectronic devices. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1558–1563 相似文献
40.
Influence of the polymer structure over self‐assembly and thermo‐responsive properties: The case of PEG‐b‐PCL grafted copolymers via a combination of RAFT and ROP 下载免费PDF全文
Mattia Sponchioni Raffaele Ferrari Lavinia Morosi Davide Moscatelli 《Journal of polymer science. Part A, Polymer chemistry》2016,54(18):2919-2931
During the last years, the field of drug delivery has experienced a growing interest toward the so‐called thermo‐responsive polymers: synthetic materials that, due to the specific hydrophilic–lipophilic balance of their repeating units, exhibit a lower critical solution temperature (LCST) in water associated to a characteristic coil–globule transition. In this work, thermo‐responsive amphiphilic block copolymers are synthesized via reversible addition‐fragmentation transfer (RAFT) polymerization starting from thermo‐responsive monomers and a hydrophobic biodegradable macromonomer, oligo(caprolactone)methacrylate (CL3MA), produced via ring opening polymerization (ROP). The obtained copolymers exhibit an interesting self‐assembly behavior leading to nanoparticles (NPs) as long as temperature is kept below the LCST. Otherwise, once this value is overcome, the destabilization of the NPs causes the formation of hydrophobic superstructures that enhance the release of an entrapped lipophilic drug. This characteristic behavior has been systematically studied and related to the copolymer structure. In particular, the self‐assembly behavior as well as temperature‐triggered NP destabilization have been related to the relative length of the two blocks constituting the copolymers and to their hydrophilic–lipophilic balance (HLB). Finally, the efficacy of the thermo‐responsive triggered drug release has been tested in the case of Paclitaxel (PTX). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2919–2931 相似文献