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991.
Automatic Mechanism and Kinetic Model Generation for Gas‐ and Solution‐Phase Processes: A Perspective on Best Practices,Recent Advances,and Future Challenges 下载免费PDF全文
Ruben Van de Vijver Nick M. Vandewiele Pierre L. Bhoorasingh Belinda L. Slakman Fariba Seyedzadeh Khanshan Hans‐Heinrich Carstensen Marie‐Françoise Reyniers Guy B. Marin Richard H. West Kevin M. Van Geem 《国际化学动力学杂志》2015,47(4):199-231
Completely automated mechanism generation of detailed kinetic models is within reach in the coming decade. The recent developments in this field of chemical reaction engineering are anticipated to lead to some groundbreaking discoveries in the future, extending our fundamental understanding and resolving many of today's society problems such as energy production and conversion, emission reduction, greener chemical production processes, etc. In the present review, the focus is on the core of these automated mechanism generation for gas‐phase and solution‐phase processes that is on how the reaction kinetics and thermodynamic and transport properties of species are estimated and calculated starting from the fundamental elements of the software. With tasks such as the definition of reaction rules and reaction families, the unambiguous representation of species, and the choice of different termination criteria, generating a good reaction mechanism is still not as simple as pressing a “run” button. One of the main challenges that still needs to be overcome is how to deal with data scarcity and the combination with affordable computational chemistry calculations seems the logical step forward. The best practices are illustrated in a butane pyrolysis case study, which also exposes the challenges in the field of automatic kinetic model generation. 相似文献
992.
Syntheses,Spectroscopic, Electrochemical,and Third‐Order Nonlinear Optical Studies of a Hybrid Tris{ruthenium(alkynyl)/(2‐phenylpyridine)}iridium Complex 下载免费PDF全文
Huajian Zhao Dr. Peter V. Simpson Adam Barlow Dr. Graeme J. Moxey Dr. Mahbod Morshedi Nivya Roy Prof. Reji Philip Prof. Chi Zhang Dr. Marie P. Cifuentes Prof. Mark G. Humphrey 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(33):11843-11854
The synthesis of fac‐[Ir{N,C1′‐(2,2′‐NC5H4C6H3‐5′‐C?C‐1‐C6H2‐3,5‐Et2‐4‐C?CC6H4‐4‐C?CH)}3] ( 10 ), which bears pendant ethynyl groups, and its reaction with [RuCl(dppe)2]PF6 to afford the heterobimetallic complex fac‐[Ir{N,C1′‐(2,2′‐NC5H4C6H3‐5′‐C?C‐1‐C6H2‐3,5‐Et2‐4‐C?CC6H4‐4‐C?C‐trans‐[RuCl(dppe)2])}3] ( 11 ) is described. Complex 10 is available from the two‐step formation of iodo‐functionalized fac‐tris[2‐(4‐iodophenyl)pyridine]iridium(III) ( 6 ), followed by ligand‐centered palladium‐catalyzed coupling and desilylation reactions. Structural studies of tetrakis[2‐(4‐iodophenyl)pyridine‐N,C1′](μ‐dichloro)diiridium 5 , 6 , fac‐[Ir{N,C1′‐(2,2′‐NC5H4C6H3‐5′‐C?C‐1‐C6H2‐3,5‐Et2‐4‐C?CH)}3] ( 8 ), and 10 confirm ligand‐centered derivatization of the tris(2‐phenylpyridine)iridium unit. Electrochemical studies reveal two ( 5 ) or one ( 6 – 10 ) Ir‐centered oxidations for which the potential is sensitive to functionalization at the phenylpyridine groups but relatively insensitive to more remote derivatization. Compound 11 undergoes sequential Ru‐centered and Ir‐centered oxidation, with the potential of the latter significantly more positive than that of Ir(N,C′‐NC5H4‐2‐C6H4‐2)3. Ligand‐centered π–π* transitions characteristic of the Ir(N,C′‐NC5H4‐2‐C6H4‐2)3 unit red‐shift and gain in intensity following the iodo and alkynyl incorporation. Spectroelectrochemical studies of 6 , 7 , 9 , and 11 reveal the appearance in each case of new low‐energy LMCT bands following formal IrIII/IV oxidation preceded, in the case of 11 , by the appearance of a low‐energy LMCT band associated with the formal RuII/III oxidation process. Emission maxima of 6 – 10 reveal a red‐shift upon alkynyl group introduction and arylalkynyl π‐system lengthening; this process is quenched upon incorporation of the ligated ruthenium moiety on proceeding to 11 . Third‐order nonlinear optical studies of 11 were undertaken at the benchmark wavelengths of 800 nm (fs pulses) and 532 nm (ns pulses), the results from the former suggesting a dominant contribution from two‐photon absorption, and results from the latter being consistent with primarily excited‐state absorption. 相似文献
993.
Synthesis of Onion‐Peel Nanodendritic Structures with Sequential Functional Phosphorus Diversity 下载免费PDF全文
Prof. Dr. Abdelkrim El Kadib Dr. Serge Mignani Dr. Anne‐Marie Caminade Prof. Dr. Mosto Bousmina Dr. Jean Pierre Majoral 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(17):6400-6408
The preparation of novel families of phosphorus‐based macromolecular architectures called “onion peel” phosphorus nanodendritic systems is reported. This construct is based on the versatility of methods of synthesis using several building blocks and on the capability of these systems to undergo regioselective reactions within the cascade structure. Sustainable metal‐free routes such as the Staudinger reaction or Schiff‐base condensation, involving only water and nitrogen as byproducts, allow access to several dendritic macromolecules bearing up to seven different phosphorus units in their backbone, each of them featuring specific reactivity. The presence of the highly aurophilic P?N?P?S fragment enables selective ligation of AuI within the dendritic framework. 相似文献
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S. Leenhardt O. Sorlin M.G. Porquet F. Azaiez J.C. Angélique M. Belleguic C. Borcea C. Bourgeois J.M. Daugas C. Donzaud I. Deloncle J. Duprat A. Gillibert S. Grévy D. Guillemaud-Mueller J. Kiener M. Lewitowicz S.M. Lukyanov F. Marie N.A. Orr Yu.-E. Penionzhkevich F. de Oliveira Santos F. Pougheon M.G. Saint-Laurent W. Shuying Yu. Sobolev J.S. Winfield 《The European Physical Journal A - Hadrons and Nuclei》2002,14(1):1-5
The reduced transition probability B(E2: 01
+→ 2+) of 72Zn has been measured for the first time by Coulomb excitation at intermediate energy. The result B(E2: 01
+→ 2+) = 1740±210 e2fm4, corresponds to the deformation parameter β2 of 0.23, in close agreement with expectations derived from the neighboring nucleus 73Zn. A discussion of the evolution of the N = 40 sub-shell closure as a function of Z is presented.
Received: 19 December 2001 / Accepted: 14 March 2002 相似文献
998.
F. Lux T. Bereznai S. Trebert Haeberlin 《Journal of Radioanalytical and Nuclear Chemistry》1987,112(1):161-168
In our determination of trace element contents of animal tissue by neutron activation analysis in the course of structure-activity relationship studies on platinum containing cancer drugs and wound healing we have tried to minimize the blank values that are caused by different sources of contarnination during surgery, sampling and the activation analysis procedure. The following topics have been investigated: the abrasions from scalpels made of stainless steel, titanium or quartz; the type of surgery; the homogenisation of the samples before irradiation by use of a ball mill; the surface contaminations of the quartz ampoules that pass into the digestion solution of the irradiated samples. The appropriate measures to be taken in order to reduce the blank values are described. The results of analyses performed under these conditions indicate the effectiveness of the given measures, especially shown by the low values obtained for the chromium contents of the analysed muscle samples. 相似文献
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