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91.
Dr. Chih‐Min Wang Li‐Wei Lee Tsung‐Yuan Chang Yen‐Chieh Chen Prof. Hsiu‐Mei Lin Prof. Kuang‐Lieh Lu Prof. Kwang‐Hwa Lii 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(5):1878-1881
An organic–inorganic hybrid zinc phosphate with 28‐ring channels was synthesized by use of an organic ligand instead of organic amine template under a hydro(solvo)thermal condition. This crystalline zinc phosphate contains large channels constructed from 28 zinc and phosphate tetrahedral units. The walls of the channels consist of two types of zincophosphate chains, in which the Zn atoms are coordinated by 2,4,5‐tri(4‐pyridyl)‐imidazole ligands as pendent groups. This compound exhibits yellow emission and interesting properties of removing cobalt, cadmium, and mercury cations from aqueous solution. A new two‐dimensional organic–inorganic hybrid zincophosphate was also obtained by changing the solvent mixture ratios in the synthesis. 相似文献
92.
Synthesis of Small‐Sized,Porous, and Low‐Toxic Magnetite Nanoparticles by Thin POSS Silica Coating 下载免费PDF全文
Dr. Swee Kuan Yen D. Prathyusha Varma Wei Mei Guo Dr. Vincent H. B. Ho Dr. Vimalan Vijayaragavan Dr. Parasuraman Padmanabhan Prof. Kishore Bhakoo Prof. Subramanian Tamil Selvan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(10):3914-3918
In this communication, we report the synthesis of small‐sized (<10 nm), water‐soluble, magnetic nanoparticles (MNPs) coated with polyhedral oligomeric silsesquioxanes (POSS), which contain either polyethylene glycol (PEG) or octa(tetramethylammonium) (OctaTMA) as functional groups. The POSS‐coated MNPs exhibit superparamagnetic behavior with saturation magnetic moments (51–53 emu g?1) comparable to silica‐coated MNPs. They also provide good colloidal stability at different pH and salt concentrations, and low cytotoxicity to MCF‐7 human breast epithelial cells. The relaxivity data and magnetic resonance (MR) phantom images demonstrate the potential application of these MNPs in bioimaging. 相似文献
93.
Cheng-Li Wang Weng-Sing Hwang Hsueh-Liang Chu Feng-Lin Yen Chi-Yuen Hwang Chi-Shiung Hsi Huey-Er Lee Moo-Chin Wang 《Journal of Sol-Gel Science and Technology》2014,70(3):428-440
The phase transformation and crystalline growth of 4 mol% yttria partially stabilized zirconia (4Y-PSZ) precursor powders have been investigated using the coprecipitation route, using zirconium oxide chloride octahydrate (ZrOCl2·8H2O) and yttrium nitrate (Y(NO3)3·6H2O) as the initial materials. Differential thermal analysis (DTA), X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), nano beam electron diffraction (NBED), and high resolution TEM (HRTEM) were utilized to characterize the behavior of phase transformation and crystalline growth of the 4Y-PSZ precursor powders after calcined. Tetragonal ZrO2 crystallization occurred at about 718.2 K. The activation energy of tetragonal ZrO2 crystallization was 227.0 ± 17.4 kJ/mol, obtained by a non-isothermal method. The growth morphology parameter (n) and growth mechanism index were close to 2.0, showing that tetragonal ZrO2 had a plate-like morphology. The crystalline size of tetragonal ZrO2 increased from 7.9 to 27.6 nm when the calcination temperature was increased from 973 to 1,273 K. The activation energies of tetragonal ZrO2 growth were 14.97 ± 0.33 and 84.46 ± 6.65 kJ/mol when precursor powders after calcined from 723–973 and 973–1,273 K, respectively. 相似文献
94.
Chih‐Yu Kuo Yu‐Cheng Wang Chia‐Fen Lee Wen‐Yen Chiu 《Journal of polymer science. Part A, Polymer chemistry》2014,52(4):561-571
Fluorescence‐incorporated, crosslinker‐free, pH‐ and thermoresponsive nanocarriers were prepared by the incorporation of drug molecules into the thermoresponsive nanocapsules, which composed of poly(N‐isopropylacrylamide) (PNIPAAm) with carboxylic acid end groups via temperature induced self‐assembling method. Well‐defined, pH‐responsive carboxylic acid group‐ended PNIPAAm homopolymer (HOOC? PNIPAAm? COOH) was synthesized by reversible addition fragmentation chain transfer polymerization with S,S′‐bis(α,α′‐dimethyl‐α″‐acetic acid)trithiocarbonate (CMP) as a chain transfer agent. Rhodamine 6G (R6G), the model drug, was used for three kinds of application: First, the nanostructure fixing; second, the fluorescence‐labeling; and last, the controlled release modeling. The transmission electron microscope images showed the solution type dosing led to the encapsulation of drug molecules into the nanocarriers, while the powder‐type drug‐loading process significantly contributed to the structure preservation of nanocarriers. The controlled release behaviors with various pH values and temperatures were evaluated. These multifunctional nanocarriers have potential to be applied for the biomedical therapy by stimuli‐responsive controlled release. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 561–571 相似文献
95.
Shih‐Ru Huang King‐Fu Lin Chia‐Fen Lee Wen‐Yen Chiu 《Journal of polymer science. Part A, Polymer chemistry》2014,52(6):848-856
The thermoresponsive magnetic polymer composites and nanofibers were fabricated. Their thermal and magnetic properties were also investigated. Fe3O4 nanoparticles were prepared by coprecipitation method. Further condensation reaction was used to fabricate the double‐layer lauric acid modified Fe3O4 (DLF) nanoparticles dispersed well in water. Thermal properties of poly(N‐isopropylacrylamide) (PNIPAAm) and DLF/PNIPAAm composites and their aqueous solutions were measured by TGA and DSC. With the increasing of DLF content, the interaction between DLF and PNIPAAm caused the lower critical solution temperature (LCST) of polymer solution to shift from 33 to 31.25 °C. The effects of concentration and pH on LCST were also studied. The DLF/PNIPAAm nanofibers were fabricated by electrospinning. Their diameters were around 100–250 nm. Magnetization curves of DLF/PNIPAAm composite and nanofibers were overlapped and the saturated magnetizations were the same. Magnetic attraction behaviors of DLF/PNIPAAm polymer solution at temperatures below and above LCST were different. Aggregation of DLF/PNIPAAm above LCST enhanced magnetic moment density as well as magnetic attraction ability. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 848–856 相似文献
96.
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98.
Clicked Isoreticular Metal–Organic Frameworks and Their High Performance in the Selective Capture and Separation of Large Organic Molecules 下载免费PDF全文
Chung Yen Ang Hongzhong Chen Dr. Jia Liu Prof. Dr. Ruqiang Zou Prof. Dr. Yanli Zhao 《Angewandte Chemie (International ed. in English)》2015,54(43):12748-12752
Three highly porous metal–organic frameworks (MOFs) with a uniform rht‐type topological network but hierarchical pores were successfully constructed by the assembly of triazole‐containing dendritic hexacarboxylate ligands with ZnII ions. These transparent MOF crystals present gradually increasing pore sizes upon extension of the length of the organic backbone, as clearly identified by structural analysis and gas‐adsorption experiments. The inherent accessibility of the pores to large molecules endows these materials with unique properties for the uptake of large guest molecules. The visible selective adsorption of dye molecules makes these MOFs highly promising porous materials for pore‐size‐dependent large‐molecule capture and separation. 相似文献
99.
We report herein the mechanochromic luminescent property of a dendritic polypeptide with a fluorescent aromatic moiety at the focal point. The different luminescent property of 1 under mechanical stimulus is attributed to the switch of self-assembled structures. Moreover, the photoluminescence property of 1 also depends on the thermal history. 相似文献
100.
Dr. Gui‐Chao Kuang Ming‐Jun Teng Prof. Xin‐Ru Jia Prof. Dr. Er‐Qiang Chen Prof. Dr. Yen Wei 《化学:亚洲杂志》2011,6(5):1163-1170
There is a delicate balance for a low‐weight molecule to behave as a gelator or crystal. The synthesis of two novel amino acid‐based naphthalene‐dendrons, Nap ‐ G1 and Nap ‐ G2 is described. Both dendrons display polymorphic properties in organic solvents. Nap ‐ G1 developed a fibrous network with β‐sheet architecture in cyclohexane but exhibited a spherulitic network in mixed solvents (chloroform/petroleum ether 1:5, v/v). On the other hand, Nap ‐ G2 acted as an efficient organogelator in chloroform but formed crystalline fibers in relatively high polarity solvents (such as acetone and methanol). Combinations of characterizations have been employed to study the polymorphism. 相似文献