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941.
Jun Li Jingjing He Jingxia Qiu Shanqing Zhang Huijun Zhao Yuqing Miao 《Electroanalysis》2010,22(10):1061-1065
An acetylcholinesterase (AChE)‐lecithin biomimetic structure was constructed at the oil/water interface for the direct determination of fenthion in cyclohexane. Indophenol acetate in oil phase was hydrolyzed by AChE at the two‐phase interface to produce indophenol. Square wave voltammetry was used to monitor the current decrease of substrate to assess AChE activity. The AChE incorporated in the lecithin‐based biomimetic layer possessed higher enzymatic activity and was more sensitive to fenthion inhibition than freestanding AChE. A linear relationship between the inhibition percentage and logarithm of fenthion concentration was obtained in a concentration range from 1 ng/mL to 1 mg/mL. 相似文献
942.
A novel blue light-emitting polyfluorene-based copolymer PTHD containing electron-rich triphenylamine and electron-poor phenylquinoline side chains in the C-9 position of fluorene unit is described. By comparison of the solution and thin film photoluminescence (PL) spectra of PTHD, a considerable red-shift of Δλ = 10-15 nm was observed in the thin film PL spectrum. The emission intensity of the shoulder peak appeared in dilute solution was also significantly enhanced in the thin film. In contrast to the reference polymer poly{[9,9-dihexylfluorene]-alt-[9,9-di(2,4-diphenylquinoline)fluorene]}, PTHD exhibits higher HOMO energy level, and higher maximum brightness with the PLED device configuration of ITO/PEDOT:PSS/polymer70% + PBD30%/TPBI/LiF/Al. 相似文献
943.
Shouwen Jin Dr. Daqi Wang Zhiwen Zheng Jie Chen Chao Feng Xianghua Ye Yiping Zhou 《无机化学与普通化学杂志》2010,636(8):1617-1624
Five novel coordination polymers, [(Cu(L1)2OH) · Cl · 3H2O] ( 1 ) [L1 = bis(N‐imidazolyl)methane], [Cd(L1)2(NCS)2] ( 2 ), [Zn(L1)2(NCS)2] ( 3 ), [Cu(L1)2(NO3)2] ( 4 ), and [Cu(L2)1.5(NCS)2] ( 5 ) [L2 = 1,4‐bis(N‐imidazolyl)butane] were obtained from self‐assembly of the corresponding metal salts with flexible ligands and their structures were fully characterized by X‐ray diffraction (XRD) analysis, Fourier Transform Infrared (FT‐IR) spectroscopy, elemental analysis and thermogravimetric (TGA) measurements. X‐ray diffraction analyses revealed that complexes 1 , 2 , 3 , and 4 exhibit 1D double‐stranded chain structures, which result from doubly bridged [CuOH], [M(NCS)2] (M = Cd, Zn), and [Cu(NO3)2] units, respectively. The polymeric copper complex 5 displays 1D ladder structure., These complexes, with the exception of complex 1 , are stable up to 300 °C. 相似文献
944.
A nonenzymatic sensor for hydrogen peroxide has been fabricated by dispersing platinum hollow nanospheres onto polypyrrole (PPy) nanowires to form a PPy-Pt hollow sphere nanocomposite on a glassy carbon electrode. The materials were characterized by transmission electron microscopy and scanning electron microscopy. The process and the sensor were characterized by electrochemical impedance spectroscopy, cyclic voltammetry, and chrono-amperometry and revealed that the electrode has a large electroactive surface area and small resistance to electron transfer. The linear range for the determination of hydrogen peroxide is from 3.5 µM to 9.9 mM, the detection limit is 1.2 µM (S/N?=?3), and the response time is 3 s. The electrode exhibited good stability and excellent repeatability. 相似文献
945.
M. V. Galkin Ye. V. Ageeva D. A. Nedosekin M. A. Proskurnin A. Yu. Olenin G. M. Mokrousov 《Moscow University Chemistry Bulletin》2010,65(2):91-97
Thermal lens spectrometry is applied to determine the absorption of transparent nanocomposite materials, which are produced
by the thermal decomposition of silver salts absorbed in the bulk of a polymethacrylate matrix. The high spatial resolution
of determination, corresponding to the size of laser beams, makes it possible to evaluate the homogeneity for the distribution
of coloration in the matrix. The advantages of thermal lens spectrometry over spectrophotometry include the weak effect of
sample scattering on the results of its absorption determination and a higher sensitivity of determination, which may exceed
that of spectrophotometry by one or two orders of magnitude. The possibility of achieving local syntheses of nanosized particles
in the bulk of the matrix by virtue of the photoinduced decomposition of silver salts in initial polyacrylate materials is
shown. Thermal lens experiments also allow the combination of the synthesis of silver nanoparticles and control of the absorbance
for the prepared structural units. 相似文献
946.
Xiao-bin Liao Yu-fang Guo Jian-hua He Wei-jian Ou Dai-qi Ye 《Plasma Chemistry and Plasma Processing》2010,30(6):841-853
A method based on high performance liquid chromatography (HPLC), has been developed to measure hydroxyl radical (·OH) in plasma reactors. The determination was performed indirectly by detecting the products of the reaction of ·OH with salicylic acid (SAL). The applicability, and effect of time, specific input energy (SIE), relative humidity (RH),
catalyst were investigated. It was found that 3 h was the optimal trapping time; concentration of ·OH was (5.9–23.6) × 1013 radicals/cm3 at SIE range. The highest ·OH yield and toluene removal efficiency (η) were achieved with a RH of 20%. With MnO
x
, η was two times that without catalyst, while ·OH yield in gas stream was one-sixth that without catalyst. However, if summed with ·OH adsorbed on catalyst surface, the total ·OH yield was the same as without catalyst. Experiments performed with/without toluene allowed to determine the role of ·OH on decomposition of toluene in air plasma. 相似文献
947.
The reactions of hexachlorocyclotriphosphazene, N3P3Cl6, with N/O donor type N-alkyl or (aryl)-o-hydroxybenzylamines HO(C6H4)CH2NHR(Ar), [R(Ar) = C(CH3)3 (1), Ph (2)] produce monospirocyclic tetrachlorocyclotriphosphazenes (1a and 2a). The geminal substituted cyclotriphosphazenes (1b, 1d, 2b and 2d) are obtained from the reactions of 1 equiv. of 1a and 2a with 2 equiv. of pyrrolidine or morpholine in THF, while the fully substituted phosphazenes (1c, 1e, 2c and 2e) are formed from the reactions of 1a and 2a with the excess pyrrolidine or morpholine in toluene, between 24 and 48 h. The microwave-assisted reactions of 1a and 2a with excess pyrrolidine or morpholine in toluene afford the fully substituted products with higher yields than those which were obtained by conventional methods. The structural investigations of the compounds have been verified by elemental analyses, ESI-MS, FTIR, 1H, 13C, 31P NMR and HETCOR techniques. The crystal structure of 2a is determined by X-ray crystallography and the phosphazene ring is in the flattened boat form. Compounds 1b, 1d, 2b and 2d in which the spiro aryloxy moiety provides the one centre of chirality exist as racemates and the chirality has been confirmed by 31P NMR spectroscopy on addition of a chiral solvating agent (CSA), (S)-(+)-2,2,2-trifluoro-1-(9′-anthryl)ethanol. 相似文献
948.
Kunping Liu Jingjing Zhang Guohai Yang Chunming Wang Jun-Jie Zhu 《Electrochemistry communications》2010,12(3):402-405
The functionalized graphene nanosheets (PDDA-G) with poly(diallyldimethylammonium chloride) (PDDA) were synthesized and used to combine with room temperature ionic liquid (RTIL). The resulting RTIL/PDDA-G composite displayed an enhanced capability for the immobilization of hemoglobin to realize its direct electrochemistry. Moreover, the RTIL/PDDA-G based biosensor exhibited excellent electrocatalytic activity for the detection of nitrate with a wide linear range from 0.2 to 32.6 μM and a low detection limit of 0.04 μM at 3σ. This work opens a new way to functionalized graphene nanosheets with good biocompatibility and solubility in biosensors. 相似文献
949.
Katie Pei Dustin Banham Fangxia Feng Tobias Fürstenhaupt Siyu Ye Viola Birss 《Electrochemistry communications》2010,12(11):1666-1669
Two mesoporous carbons (with 15 (CIC-15) and 26 nm (CIC-26) diameter pores) were synthesized using a silica colloid imprinting method, loaded with 10 wt.% Pt, and then evaluated (against Vulcan? carbon (VC)) as oxygen reduction (ORR) catalysts for use in proton exchange membrane fuel cells. Both Pt/CICs reproducibly out-performed Pt/VC, with Pt/CIC-15 demonstrating higher ORR activity than Pt/CIC-26, despite its smaller pore size and lower surface area. Transmission electron tomography showed that the Pt nanoparticles (4–5 nm diameter) are fully deposited throughout the pores of the CICs and that the pore distribution in CIC-26 is partially ordered, while CIC-15 shows no ordering of its pores. Importantly, using the powerful imaging capabilities of transmission electron tomography, a first-time correlation is demonstrated between the ORR activity and the wall thickness of the carbon support materials. Pt/CIC-15 has significantly thicker walls, giving a lower measured electronic resistance, a lower ORR Tafel slope, and thus better performance overall compared to Pt/CIC-26. 相似文献
950.
Xiaoteng Luo Jingjing Xu John Barford I-Ming Hsing 《Electrochemistry communications》2010,12(4):531-534
This work reports a novel electrochemical PCR detection platform using magnetic particles as a separation tool. A redox-active intercalator, anthraquinonemonosulfonic acid (AQMS), was firstly intercalated into biotin labeled PCR amplicons, and the resulting complex was then captured by streptavidin-coated magnetic particles (MPs) to form AQMS–DNA–MP conjugates. Subsequently, these conjugates were attracted to the bottom of the tube and separated from the solution by applying an external magnetic field, resulting in a significant reduction of the concentration of solution AQMS. The concentration changes of solution AQMS, which reflect the presence and quantity of PCR amplicons, were monitored by differential pulse voltammetry (DPV) on a chip electrode. PCR cycle number-dependent as well as the initial template DNA concentration-dependent performances were investigated. This electrochemistry based PCR detection platform is simple, convenient and inexpensive, and may have potential applications for practical sample monitoring. 相似文献