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51.
A Colorimetric and Fluorimetric Chemodosimeter for Copper Ion Based on the Conversion of Dihydropyrazine to Pyrazine 下载免费PDF全文
Dr. Junbo Li Shao Chen Pian Zhang Zilong Wang Guankui Long Dr. Rakish Ganguly Dr. Yongxin Li Prof. Dr. Qichun Zhang 《化学:亚洲杂志》2016,11(1):136-140
In this research, we successfully synthesized and fully characterized the new compound 5,8,13,16,21,24‐hex‐(triisopropylsilyl)ethynyl)‐6,23‐dihydro‐6,7,14,15,22,23‐hexaza‐trianthrylene ( HHATA , brown color in a mixed solvent of CH2Cl2/CH3CN 1:1, v/v, weakly blue fluorescent), which can be easily oxidized to 5,8,13,16,21,24‐hex‐(triisopropylsilyl)ethynyl)‐6,7,14,15,22,23‐hexazatrianthrylene ( HATA ) (yellow color in CH2Cl2/CH3CN 1:1, v/v), red fluorescent) by Cu2+ ions. This reaction only proceeds efficiently in the presence of Cu2+ ions when compared with other common metal ions such as Fe3+, Co2+, Mn2+, Hg2+, Ni2+, Pb2+, Ag+, Mg2+, Ca2+, K+, Na+, and Li+. Our result suggests that this reaction can be developed as an effective method for the detection of Cu2+ ions. 相似文献
52.
Ajay K. Bose Subhendu N. Ganguly Maghar S. Manhas Vaidyanathan Srirajan Ashoke Bhattacharjee Sochanchingwung Rumthao Anju H. Sharma 《Tetrahedron letters》2004,45(6):1179-1181
A novel dinitro secondary metabolite, 2-nitro-4-(2′-nitroethenyl)phenol from a marine source, has been prepared via highly accelerated, microwave assisted, nitration reactions using mild reagents. ipso-Substitution of a carboxy group by a nitro group is discussed. 相似文献
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54.
Differential equations of different types and orders are of utmost importance for mathematical modeling of control system problems. State variable method uses the concept of expressing n number of first order differential equations in vector matrix form to model and analyze/synthesize control systems.The present work proposes a new set of orthogonal hybrid functions (HF) which evolved from synthesis of sample-and-hold functions (SHF) and triangular functions (TF). This HF set is used to approximate a time function in a piecewise linear manner with the mean integral square error (MISE) much less than block pulse function based approximation which always provides staircase solutions.The operational matrices for integration and differentiation in HF domain are also derived and employed for solving non-homogeneous and homogeneous differential equations of the first order as well as state equations. The results are compared with exact solutions, the 4th order Runge-Kutta method and its further improved versions proposed by Simos [6]. The presented HF domain theory is well supported by a few illustrations. 相似文献
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56.
Krishanu Nandy Sayani Chaudhuri Ranjan Ganguly Ishwar K. Puri 《Journal of magnetism and magnetic materials》2008
Magnetic microspheres are used as mobile substrates in micro-total-analysis systems (μTAS), since the particles can be selectively functionalized to attach different bioconjugates and can be precisely manipulated using external magnetic field gradients. A large number of MEMS-based bio-analytical devices employ magnetophoretic separation as an important step during their operation. An analytical technique is proposed in this paper that describes the magnetophoretic transport of magnetic microspheres under an imposed magnetic field when there is a pressure-driven or electroosmotic flow through a microchannel. Successful magnetophoretic capture occurs if the strength of the field-inducing magnetic dipole exceeds a critical value, or if the particles are larger than a critical size. The magnetophoretic separator performance is characterized in terms of capture efficiency. The analysis shows that the capture efficiency is a function of two independent non-dimensional parameters, λ and γ that in turn involve all the physical design and operating parameters of the microfluidic separator, e.g., the dipole strength, particle size and susceptibility, fluid viscosity and velocity, channel height, and the separation of the dipole. Parametric plots of capture efficiency as function of λ and γ helps in choosing the right design and operation parameter of a practical microfluidic separator for a target level of performance. 相似文献
57.
Analysis of Ti:LiNbO3 zero-gap directional coupler for wavelength division multiplexer/demultiplexer
Pranabendu Ganguly Juran Chandra Biswas Samir Kumar Lahiri 《Optics Communications》2008,281(12):3269-3274
For the purpose of multichannel integrated-optical wavelength division MUX/DEMUX design, the wavelength tuning method of Ti:LiNbO3 zero-gap directional coupler is analysed by effective-index based matrix method (EIMM). In this method, first, the 2D refractive index profile of the Ti:LiNbO3 zero-gap directional coupler is transformed into lateral 1D effective-index profile by WKB method. Finally, matrix method is applied to this effective-index profile and the propagation constants are computed from the resonance peaks of the excitation efficiency versus propagation constant characteristics. It has been shown that the channel wavelength tuning can be achieved by varying the Y-branching angle at the input and output of the device or by a slight variation of two-mode-section length. The method of electro-optic fine tuning of the channel wavelength and channel separation of the device has also been investigated. A cascaded structure with proper parameters for four-channel application is also simulated and the results are presented. 相似文献
58.
Soumya Basu Basab Chattopadhyay A. Ganguly P. Chakraborty P. Roy Chowdhury S. Samanta M. Mukherjee A. K. Mukherjee S. K. Choudhuri 《应用有机金属化学》2009,23(12):527-534
A mononuclear copper (II) complex of N‐2‐hydroxyhippuric acid (2HHA), [Cu(HA)(H2O)2], has been synthesized and characterized by spectroscopic and X‐ray powder diffraction studies. Crystal structure of [Cu(HA)(H2O)2] reveals a distorted square‐pyramidal geometry around the metal center. The crystal packing in the complex exhibits a three‐dimensional framework formed by intermolecular O? ; H···O and C? H···O hydrogen bonds. Toxicity and antitumor properties of the complex have been studied in vivo. The complex, capable of depleting glutathione (GSH) at nontoxic doses, may be utilized to sensitize drug‐resistant cells where resistance is due to an elevated level of GSH. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
59.
Subhendu Naskar Priyankar Paira Rupankar Paira Shyamal Mondal Arindam Maity Abhijit Hazra Krishnendu B. Sahu Pritam Saha Sukdeb Banerjee Peter Luger Manuela Webe Nirup B. Mondal 《Tetrahedron》2010,66(27-28):5196-5203
An environmentally benign protocol has been described for the synthesis of novel 2-(1′,3′-dihydro-1H-[2,3′]biindolyl-2′-ylidene)-indan-1,3-diones/bis-indolylindane-1,3-diones from ninhydrin and 3-substituted/unsubstituted indoles. It uses montmorillonite K-10 as catalyst in a solvent-free condition under microwave irradiation. The method was also used for the synthesis of novel bisindolylindeno[1,2-b]quinoxaline derivatives. 相似文献
60.
Bishwajit Ganguly Marija Matković Nikola Basarić Kata Mlinarić‐Majerski 《Journal of Physical Organic Chemistry》2011,24(7):578-587
The hydrolysis of ethyl threo‐2‐(1‐adamantyl)‐3‐hydroxybutyrate ( 1 ) and the parent ester ethyl 3‐hydroxybutyrate ( 4 ) has been studied experimentally and computationally. In the hydrolysis of threo‐ester 1 with 2 M NaOH, predominantly retro‐aldol product was observed, whereas the hydrolyzed product was present in a minor amount. When the reaction is carried out under the same conditions with the parent ester ethyl 3‐hydroxybutyrate ( 4 ), hydrolyzed product is exclusively observed. The competitive pathways, namely hydrolysis and the retro‐aldol reaction for 1 and 4 were investigated using DFT calculations in the both gas and solvent phase. The calculated results in the solvent phase at B3LYP/6–31 + G* level revealed that the formation of retro‐aldol products is kinetically preferred over the hydrolysis of threo‐ester 1 in the presence of a base. However, the parent ester 4 showed that the retro‐aldol process is less favored than the hydrolysis process under similar conditions. The steric effect imposed by the bulky adamantyl group to enhance the activation barriers for the hydrolysis of the ethyl threo‐2‐(1‐adamantyl)‐3‐hydroxybutyrate ( 1 ) was further supported by the calculations performed with tert‐butyl group at the α‐carbon atom of ethyl 3‐hydroxybutyrate ( 7 ). Copyright © 2010 John Wiley & Sons, Ltd. 相似文献