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51.
Prakash Sista Mahesh P. Bhatt Ashton R. Mccary Hien Nguyen Jing Hao Michael C. Biewer Mihaela C. Stefan 《Journal of polymer science. Part A, Polymer chemistry》2011,49(10):2292-2302
Poly{4,8‐bis(4‐decylphenylethynyl)benzo[1,2‐b:4,5‐b′]dithiophene} ( P1 ) homopolymer and poly{4,8‐bis(4‐decylphenylethynyl)benzo[1,2‐b:4,5‐b′]dithiophene ‐alt‐thiophene} ( P2 ) alternating copolymer have been synthesized by Stille coupling polymerization. The field‐effect mobilities of both polymers were measured on both untreated and silane‐treated OFET devices. Various silanes were selected to allow an incremental increase in the hydrophobicity of the silicon dioxide dielectric. A direct correlation was observed between the hydrophobicity of the silicon dioxide dielectric surface and the enhancement of the field‐effect mobilities. The highest mobilities for both polymers were measured on the OFET devices treated with heptadecafluoro‐1,1,2,2‐tetrahydro‐decyl‐1‐trimethoxysilane (FS) which generated the most hydrophobic surface. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
52.
Mahesh M. SavantNeetha S. Gowda Akshay M. PansuriyaChirag V. Bhuva Naval KapuriyaSridhar M. Anandalwar Shashidhara J. PrasadAnamik Shah Yogesh T. Naliapara 《Tetrahedron letters》2011,52(2):254-257
A highly efficient strategy to 2,3-substituted chromen-4H-ones has been developed. The methodology involves unexpected intramolecular heteroannulation of readily accessible substituted 2-hydroxy-ω-nitroacetophenone with carbon disulfide in the presence K2CO3 followed by methylation with methyl iodide. These chromenones were further reacted with various nucleophiles such as amines, thiols, and alkoxide resulting in the facile C-N, C-S, and C-O bond formation. The scope and generality have been discussed. 相似文献
53.
54.
Mahesh S. Majik Perunninakulath S. Parameswaran Santosh G. Tilve 《Helvetica chimica acta》2008,91(8):1500-1504
A straightforward synthesis of (S)‐pyrrolam A is described. The synthesis involves in situ generation of the phosphorane 3 , followed by an intramolecular Wittig reaction to furnish (S)‐pyrrolam A. 相似文献
55.
Subhash P. Chavan Mahesh Thakkar Ashok B. Pathak Mohan M. Bhadbhade 《Tetrahedron》2005,61(15):3873-3879
The first enantiospecific synthesis of (+)-β-herbertenol, from naturally occurring R-(+)-citronellal, employing Taber's diazo decomposition protocol as the key step, is described. 相似文献
56.
4S-Aminoproline polypeptide 2 forms unusual β-structure in trifluoroethanol that switches to the polyproline II (PPII) form in aqueous medium, while 4R-aminoproline peptide 1 retains PPII form in both solvents. This first instance of a polyproline derivative showing a β-structure is attributed to competitive pH-dependent (4-NH(3)(+)/NH(2)) stereoelectronic effect (4R vs 4S) and the overriding importance of stereospecific intra/intermolecular H-bonding in (2,4)-cis-4S-aminoproline in contrast to (2,4)-trans-4R-aminoproline oligomers. 相似文献
57.
Mahesh Chander Gupta 《Accreditation and quality assurance》2010,15(10):591-593
The ISO/IEC 17025 standard requires that all documents that form part of the management system of the organization must be
controlled. However, as customary, the certificates issued from testing or calibration laboratories do no bear any unique
identity mark/number similar to other documents to announce control over the document. This leaves enough room for doubt to
many in treating this document at par with other management system documentation. Some auditors had raised this question during
accreditation visits. 相似文献
58.
Mahesh Kumar Thirumaleshwara N. Bhat Mohana K. Rajpalke Basanta Roul Neeraj Sinha A.T. Kalghatgi S.B. Krupanidhi 《Surface science》2011,605(15-16):L33-L37
InN layers were directly grown on Ge substrate by plasma-assisted molecular beam epitaxy (PAMBE). The valence band offset (VBO) of wurtzite InN/Ge heterojunction is determined by X-ray photoemission spectroscopy (XPS). The valence band of Ge is found to be 0.18 ± 0.04 eV above that of InN and a type-II heterojunction with a conduction band offset (CBO) of ~ 0.16 eV is found. The accurate determination of the VBO and CBO is important for the design of InN/Ge based electronic devices. 相似文献
59.
Mahesh Kumar Mohana K. RajpalkeBasanta Roul Thirumaleshwara N. BhatNeeraj Sinha A.T. KalghatgiS.B. Krupanidhi 《Applied Surface Science》2011,257(6):2107-2110
Ultra thin films of pure silicon nitride were grown on a Si (1 1 1) surface by exposing the surface to radio-frequency (RF) nitrogen plasma with a high content of nitrogen atoms. The effect of annealing of silicon nitride surface was investigated with core-level photoelectron spectroscopy. The Si 2p photoelectron spectra reveals a characteristic series of components for the Si species, not only in stoichiometric Si3N4 (Si4+) but also in the intermediate nitridation states with one (Si1+) or three (Si3+) nitrogen nearest neighbors. The Si 2p core-level shifts for the Si1+, Si3+, and Si4+ components are determined to be 0.64, 2.20, and 3.05 eV, respectively. In annealed sample it has been observed that the Si4+ component in the Si 2p spectra is significantly improved, which clearly indicates the crystalline nature of silicon nitride. The high resolution X-ray diffraction (HRXRD), scanning electron microscopy (SEM) and photoluminescence (PL) studies showed a significant improvement of the crystalline qualities and enhancement of the optical properties of GaN grown on the stoichiometric Si3N4 by molecular beam epitaxy (MBE). 相似文献
60.
Mahesh Kumar Basanta Roul Thirumaleshwara N. Bhat Mohana K. Rajpalke Neeraj Sinha A. T. Kalghatgi S. B. Krupanidhi 《Journal of nanoparticle research》2011,13(3):1281-1287
One of the scientific challenges of growing InN quantum dots (QDs), using Molecular beam epitaxy (MBE), is to understand the
fundamental processes that control the morphology and distribution of QDs. A systematic manipulation of the morphology, optical
emission, and structural properties of InN/Si (111) QDs is demonstrated by changing the growth kinetics parameters such as
flux rate and growth time. Due to the large lattice mismatch, between InN and Si (~8%), the dots formed from the Strannski–Krastanow
(S–K) growth mode are dislocated. Despite the variations in strain (residual) and the shape, both the dot size and pair separation
distribution show the scaling behavior. We observed that the distribution of dot sizes, for samples grown under varying conditions,
follow the scaling function. 相似文献