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排序方式: 共有358条查询结果,搜索用时 15 毫秒
351.
Masoud Salavati-Niasari Hamideh Seyghalkar Omid Amiri Fatemeh Davar 《Journal of Cluster Science》2013,24(1):365-376
α-Ni(OH)2 flower-like nanostructures were successfully synthesized through one-step hydrothermal method with nickel acetate tetrahydrate, ethylene-1,2-diamine (en), hexamethylenetetramine (HMT) and cetyltrimethylammonium bromide (CTAB) as morphology-directing agents. Optimum conditions to obtain high yield and pure phase α-Ni(OH)2 were identified by varying experimental parameters such as: en, HMT and CTAB concentration and reaction temperature. The products were characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared and thermogravimetric analysis. These results indicated that the α-nickel hydroxide contains water molecules and anions. The hierarchical NiO nanostructures were obtained by the as-synthesized α-Ni(OH)2 nanostructures annealed at 300 °C for 4 h. 相似文献
352.
Issa Yavari Rahebeh Amiri Mina Haghdadi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1681-1692
Ab initio Hartree–Fock calculations at the HF/6-31G* level of theory for geometry optimization and the MP2/6-31G*//HF/6-31G* and B3LYP/6-311G(2df,p)//HF/6-31G* levels for a single point total energy calculation are reported for the important energy-minimum conformations of 1,1-dioxo-thiane (2), 1,1-dioxo-1,2-dithiane (3), 1,1-dioxo-1,3-dithiane (4), 1,1-dioxo-1,4-dithiane (5), 1,1,2-trioxo-1,2-dithiane (6), 1,1,3-trioxo-1,3-dithiane (7), 1,1,4-trioxo-1,4-dithiane (8), 1,1,2,2-tetroxo-1,2-dithiane (9), 1,1,3,3-tetroxo-1,3-dithiane (10), and 1,1,4,4-tetroxo-1,4-dithiane (11). According to the MP2/6-31G*//HF/6-31G* calculations, compound 5 is more stable than 3 and 4 by 7.8 and 8.9 kJ mol?1, respectively. The axial geometries of 6 and 8 are more stable than the equatorial forms by 21.4 and 19.1 kJ mol?1, respectively, but the equatorial form of 7 is 4.1 kJ mol?1 more stable than the axial geometry. Compound 11 is more stable than 9 and 10 by 49.3 and 31.0 kJ mol?1, respectively. 相似文献
353.
Rahebeh Amiri Mina Haghdadi Ashkan Golshani Maryam Mohamadian Amiri Maryam Barikani 《中国化学会会志》2013,60(1):45-52
We have reported a simple and efficient reaction for the synthesis of some new functionalized azo structures which were prepared by electron deficient acetylenic compounds in the presence of triphenylphosphine. The characterization of the synthesized azo compounds has been determined by FTIR, UV‐Vis, 1H NMR, 13C NMR and Mass spectroscopic techniques. The influence of H‐bonding on the products has been shown by different experimental analysis. Also, the regioselectivity of the reaction, tautomerization equilibrium and the stability of products was investigated using DFT calculations at the B3LYP/6‐31G level of theory. 相似文献
354.
Majid Montazer Morteza Maali Amiri Reza Mohammad Ali Malek 《Photochemistry and photobiology》2013,89(5):1057-1063
This study has been carried out to synthesize nano ZnO on wool fabric and also to investigate influences of nano photo reactors on wool fabric characteristics. Zinc acetate has been used as a precursor and the synthesis process has been done in water and water/ethanol media. The treated wool fabrics were heated at 80°C for 10 h to dehydrate Zn(OH)2 obtaining ZnO. The fabric samples were then subjected to daylight for 7 days to examine the influence of nano ZnO photo reactor on the fabric properties. SEM images revealed the embedding of ZnO nanoparticles on the fabrics and X‐ray diffraction verified the nanoparticles composition. The Yellowness Index (YI) of the fabrics was measured with Color Eye XTH that has been reduced with increasing pH, Zn(CH3COO)2 concentration, ethanol and heating. The lower water contact angle and time of water absorption confirmed higher hydrophilic properties of the treated fabrics. Interestingly, a higher tensile strength obtained on the wool fabrics proved the interaction of ZnO with protein chains of wool, which was verified through lower alkali solubility of treated fabric with nano ZnO and confirmed more benefits of the in situ synthesis process. 相似文献
355.
Giuseppe A. Consiglio Salvatore Failla Paolo Finocchiaro Mandana Visi Kenneth I. Hardcastle 《Supramolecular chemistry》2013,25(3):177-184
Abstract Three novel polyether macrocycles II-IV bearing phosphonic groups have been synthesised in satisfactory yields. Macrocycle II was found to form a 1:1 inclusion compound with cyclohexane and thus was easily isolated from the reaction mixture as a clathrate. The crystal and molecular structure of the cyclohexane solvate has been determined by single crystal X-ray analyses and refined to an R of 0.028 for 3199 reflection. The compound is monoclinic, space group P21n with a = 15.886(6) Å, b = 11.657(5) Å, c = 18.621 (6) Å, β = 90.12(3)°, Z = 2. The whole molecule exhibits a great deal of disorder and the different conformations were modelled as consisting of two different primary conformers with population approximately 60:40. 相似文献
356.
Solvatochromic mixed-chelate copper(II) complexes, [Cu(Cl-acac)(diamine)]X (where Cl-acac = 3-chloroacetylacetonate ion, diamine = N,N′-dimethyl,N′-benzyl-1,2-diaminoethane and X = B(Ph)4−, PF6−, BF4− and ClO4−), have been prepared. The complexes were characterized on the basis of elemental analysis, molar conductance, UV-Vis and IR spectroscopies. Single crystals of [Cu(Cl-acac)(diamine)(H2O)]PF6, complex 2, were also characterized by X-ray diffraction. The influence of the solvent polarity and counter ions on the νmax values of the d-d bands of the complexes have been investigated by means of visible spectroscopy. All the complexes demonstrated negative solvatochromism. A multi-parametric equation has been utilized to explain the solvent effect on the d-d transition of the complexes using SPSS/PC software. The stepwise multiple linear regression (SMLR) method demonstrated that the donor power of the solvent plays the most important role in the solvatochromism of the compounds. The relative donor power of the anions X was determined by visible spectra in the solvent dichloromethane. 相似文献
357.
Seyed Hanif Mahboobi Ali Meghdari Nader Jalili Farshid Amiri 《Central European Journal of Physics》2011,9(2):454-465
Molecular dynamics simulations are carried out to investigate the manipulation of metallic clusters on stepped surfaces. Five
surface forms are considered in the simulations. The system parts are made of pure transition metals and Sutton-Chen many-body
potential is used as interatomic potential. The conditions which are subjected to change in the tests include: materials used
for particles and substrate, and surface step conditions. In addition to qualitative observations, two criteria which represent
the particle deformation and substrate abrasion are utilized as evaluation tools and are computed for each case. Simulation
results show the effect of the aforementioned working conditions on the particle behavior as well as changes in the pushing
forces. Obtaining this sort of knowledge is highly beneficial for further experiments in order to be able to plan the conditions
and routines which guarantee better success in the manipulation process. 相似文献
358.
Banafsheh Honarvari Sara Karimifard Niyayesh Akhtari Mehrnoush Mehrarya Zahra Salehi Moghaddam Mohammad Javed Ansari Abduladheem Turki Jalil Adrin Matencio Francesco Trotta Faten Eshrati Yeganeh Bahareh Farasati Far Mandana Kazem Arki Mohammad Reza Naimi-Jamal Hassan Noorbazargan Zahra Asghari Lalami Mohsen Chiani 《Molecules (Basel, Switzerland)》2022,27(14)
As the most common cancer in women, efforts have been made to develop novel nanomedicine-based therapeutics for breast cancer. In the present study, the in silico curcumin (Cur) properties were investigated, and we found some important drawbacks of Cur. To enhance cancer therapeutics of Cur, three different nonionic surfactants (span 20, 60, and 80) were used to prepare various Cur-loaded niosomes (Nio-Cur). Then, fabricated Nio-Cur were decorated with folic acid (FA) and polyethylene glycol (PEG) for breast cancer suppression. For PEG-FA@Nio-Cur, the gene expression levels of Bax and p53 were higher compared to free drug and Nio-Cur. With PEG-FA-decorated Nio-Cur, levels of Bcl2 were lower than the free drug and Nio-Cur. When MCF7 and 4T1 cell uptake tests of PEG-FA@Nio-Cur and Nio-Cur were investigated, the results showed that the PEG-FA-modified niosomes exhibited the most preponderant endocytosis. In vitro experiments demonstrate that PEG-FA@Nio-Cur is a promising strategy for the delivery of Cur in breast cancer therapy. Breast cancer cells absorbed the prepared nanoformulations and exhibited sustained drug release characteristics. 相似文献