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排序方式: 共有1070条查询结果,搜索用时 15 毫秒
1.
Lin Hui-Min Mu Chao Li Ao Liu Xu-Feng Li Yu-Long Jiang Zhong-Qing Wu Hong-Ke 《Transition Metal Chemistry》2019,44(5):491-498
Transition Metal Chemistry - In this paper, four diiron toluene-3,4-dithiolate complexes with phosphine ligands were synthesized and characterized. Treatment of complex... 相似文献
2.
Zhengyang Yang Jiafeng Wang Song Liu Feng Sun Ji Miao En Xu Liang Tao Yuxin Wang Shichao Ai Wenxian Guan 《Particle & Particle Systems Characterization》2019,36(7)
Photothermal therapy (PTT) is an emerging noninvasive and precise localized therapeutic modality; however, it is deeply limited by its poor tumor accumulation, inadequate photothermal conversion efficiency, and the thermoresistance of cancer cells. Aimed at these shortcomings, tumor‐targeting nanoparticles (iRGD‐W18O49‐17AAG) comprising carboxyl‐group‐functionalized W18O49 nanoparticles, integrin‐targeting peptide iRGD, and HSP90‐inhibitor 17AAG are developed. The W18O49 nanoparticles act as excellent PTT carriers and computed tomography (CT) imaging contrast agents. The ring type polypeptide iRGD promotes the accumulation of nanoparticles in the tumour and further penetration into cancer cells. The introduction of 17AAG can inhibit the heat‐shock response and overcome the thermoresistance, thus increasing the curative effect of PTT and reducing the chance of tumor recurrence. The W18O49 nanoparticles can also be used to monitor and guide the phototherapeutic through CT and near‐infrared fluorescence imaging after modification with Cy5.5. In addition, superior biosafety is also indicated in both preliminary in vitro and in vivo assessments. The potential of iRGD‐W18O49‐17AAG in tumor targeting, dual modality imaging‐guided and remarkable enhanced PTT of gastric cancer with ignorable side effect both in vitro and in vivo, which may be further applied in clinic, is highlighted. 相似文献
3.
With the ever‐increasing concerns on environmental pollution and energy crisis, it is of great urgency to develop high‐performance photocatalyst to eliminate organic pollutants from wastewater and produce hydrogen via water splitting. Herein, a polypyridyl‐based mixed covalent CuI/II complex with triangular {Cu3} and rhombic {Cu2Cl4} subunits alternately extended by mixed SCN– and Cl– heterobridges [Cu4(DNP)(SCN)Cl4]n ( 1 ) [DNP = 2,6‐bis(1,8‐naphthyridine‐2‐yl)pyridine] was solvothermally synthesized and employed as a dual‐functional co‐photocatalyst. Resulting from a narrowed band‐gap of 1.07 eV with suitable redox potential and unsaturated CuI/II sites, the complex together with H2O2 can effectively degrade Rhodamine B and methyl orange up to 87.4 and 88.2 %, respectively. Meanwhile, the complex mixed with H2PtCl6 can also accelerate the photocatalytic water splitting in the absence of a photosensitizer with the hydrogen production rate of 27.5 μmol · g–1 · h–1. These interesting findings may provide informative hints for the design of the multiple responsive photocatalysts. 相似文献
4.
Hailong Zhang Wei Liu Ao Li Duo Zhang Xiaoyan Li Fuwan Zhai Lanhua Chen Long Chen Yanlong Wang Shuao Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(45):16256-16260
The design and synthesis of uranium sorbent materials with high uptake efficiency, capacity and selectivity, as well as excellent hydrolytic stability and radiation resistance remains a challenge. Herein, a polyoxometalate (POM)–organic framework material ( SCU‐19 ) with a rare inclined polycatenation structure was designed, synthesized through a solvothermal method, and tested for uranium separation. Under dark conditions, SCU‐19 can efficiently capture uranium through ligand complexation using its exposed oxo atoms and partial chemical reduction from UVI to UIV by the low‐valent Mo atoms in the POM. An additional UVI photocatalytic reduction mechanism can occur under visible light irradiation, leading to a higher uranium removal without saturation and faster sorption kinetics. SCU‐19 is the only uranium sorbent material with three distinct sorption mechanisms, as further demonstrated by X‐ray photoelectron spectroscopy (XPS) and X‐ray absorption near edge structure (XANES) analysis. 相似文献
5.
Jia-Bin Han Ao Guo Prof. Xiang-Ying Tang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(12):2989-2994
A challenging deoxygenation of alkoxyl radicals from readily accessible alcohol derivatives was developed, affording facile synthesis of functionalized alkenes with good functional group tolerance under mild reaction conditions. Because alkoxyl radicals can easily undergo β-fragmentations or hydrogen abstractions, this new strategy for deoxygenation of alkoxyl radicals is highly valuable. Moreover, mechanistic studies revealed that the electron-neutral phosphine acts as the deoxygenation reagent. 相似文献
6.
In this paper, we study polynomials orthogonal with respect to a Pollaczek–Jacobi type weight The uniform asymptotic expansions for the monic orthogonal polynomials on the interval (0,1) and outside this interval are obtained. Moreover, near , the uniform asymptotic expansion involves Airy function as , and Bessel function of order α as in the neighborhood of , the uniform asymptotic expansion is associated with Bessel function of order β as . The recurrence coefficients and leading coefficient of the orthogonal polynomials are expressed in terms of a particular Painlevé III transcendent. We also obtain the limit of the kernel in the bulk of the spectrum. The double scaled logarithmic derivative of the Hankel determinant satisfies a σ‐form Painlevé III equation. The asymptotic analysis is based on the Deift and Zhou's steepest descent method. 相似文献
7.
Xuejiao Hu Tiancheng Li Yidan Tang Yirong Wang Dr. Ao Wang Dr. Gengtao Fu Prof. Xiaodong Li Prof. Yawen Tang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(31):7561-7568
The development of high-efficiency electrocatalysts with low costs for the oxygen evolution reaction (OER) is essential, but remains challenging. Herein, a new synthetic process is proposed to prepare Ni3S4 particles embedded in N,P-codoped honeycomb porous carbon aerogels (Ni3S4/N,P-HPC) through a hydrogel approach. The preparation of Ni3S4/N,P-HPC begins with the sol–gel polymerization of tripolyphosphate, chitosan, and guanidine polymer that contains metal-binding sites, allowing for the uniform incorporation of Ni ions into the gel matrix, freeze-drying, and subsequent carbonization under an inert atmosphere. This synthesis resolves difficulties in synthesizing the pure Ni3S4 phase caused by the instability of Ni3S4 at high temperature, while affording good control of the porous structure and N,P-doping of carbon aerogels. The synergy between the structural advantages of N,P-carbon aerogels (such as easily accessible active sites, high specific surface area, and excellent electron transport) and the intrinsic electrochemical properties of Ni3S4 result in the outstanding OER performance of Ni3S4/N,P-HPC, with overpotentials as low as 0.37 V at 10 mA cm−2. The work outlined herein offers a simple and effective method for the development of carbon-based electrocatalysts for renewable energy conversion. 相似文献
8.
Hui‐Min Lin Jian‐Rong Li Chao Mu Ao Li Xu‐Feng Liu Pei‐Hua Zhao Yu‐Long Li Zhong‐Qing Jiang Hong‐Ke Wu 《应用有机金属化学》2019,33(11)
Five monophosphine‐substituted diiron propane‐1,2‐dithiolate complexes as the active site models of [FeFe]‐hydrogenases have been synthesized and characterized. Reactions of complex [Fe2(CO)6{μ‐SCH2CH(CH3)S}] ( 1 ) with a monophosphine ligand tris(4‐methylphenyl)phosphine, diphenyl‐2‐pyridylphosphine, tris(4‐chlorophenyl)phosphine, triphenylphosphine, or tris(4‐fluorophenyl)phosphine in the presence of the oxidative agent Me3NO·2H2O gave the monophosphine‐substituted diiron complexes [Fe2(CO)5(L){μ‐SCH2CH(CH3)S}] [L = P(4‐C6H4CH3)3, 2 ; Ph2P(2‐C5H4N), 3 ; P(4‐C6H4Cl)3, 4 ; PPh3, 5 ; P(4‐C6H4F)3, 6 ] in 81%–94% yields. Complexes 2 – 6 have been characterized by elemental analysis, spectroscopy, and X‐ray crystallography. In addition, electrochemical studies revealed that these complexes can catalyze the reduction of protons to H2 in the presence of HOAc. 相似文献
9.
10.
High‐Nuclear Organometallic Copper(I)–Alkynide Clusters: Thermochromic Near‐Infrared Luminescence and Solution Stability 下载免费PDF全文
Hong‐Yan Zhuo Dr. Hai‐Feng Su Zhao‐Zhen Cao Wei Liu Prof. Shu‐Ao Wang Lei Feng Dr. Gui‐Lin Zhuang Dr. Shui‐Chao Lin Prof. Mohamedally Kurmoo Prof. Chen‐Ho Tung Dr. Di Sun Prof. Lan‐Sun Zheng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(49):17619-17626
Cu(CF3COO)2 reacts with tert‐butylacetylene (tBuC≡CH) in methanol in the presence of metallic copper powder to give two air‐stable clusters, [CuI15(tBuC≡C)10(CF3COO)5]?tBuC≡CH ( 1 ) and [CuI16(tBuC≡C)12(CF3COO)4(CH3OH)2] ( 2 ). The assembly process involves in situ comproportionation reaction between Cu2+ and Cu0 and the formation of two different clusters is controlled by reactants concentration. The clusters consist of Cu15 and Cu16 cores co‐stabilized by strong by σ‐ and π‐bonded tert‐butylethynide and CF3COO? (together with methanol molecule in 2 ). Their stabilities in solution were confirmed using electrospray ionization mass spectrometry in which the cluster core remains intact for 1 in chloroform and acetone, and for 2 in acetonitrile. Strong thermochromic luminescence in the near infrared (NIR) region was observed in the solid‐state. Of particular interest, the emission maximum of 1 is red‐shifted from 710 nm at 298 K to 793 nm at 93 K, along with a 17‐fold fluorescence enhancement. In contrast, 2 exhibits red shift from 298 to 123 K followed by blue shift from 123 to 93 K. The emission wavelength was correlated with the structural parameters using variable‐temperature X‐ray single‐crystal analyses. The rich cuprophilic interaction plays a significant role in the formation of 3LMCT (tBuC≡C→Cux) excited state mixed with cluster‐centered (3CC) characters, which can be considerably influenced by temperature, leading to thermochromic luminescence. The present work provides 1) a new synthetic protocol for the high‐nuclear CuI–alkynyl clusters; 2) a comprehensive insight into the mechanism of thermochromic luminescence; 3) unusual emissive materials with the characters of NIR and thermochromic luminescence simultaneously. 相似文献