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91.
We experimentally demonstrated remote sensing of the constituents of microparticles in air by combining laser-induced breakdown spectroscopy (LIBS) and lidar, using femtosecond terawatt laser pulses. Laser pulses of 70 fs duration and 130 mJ energy generated filaments when focused at a focal length of 20 m and the pulses irradiated artificial saltwater aerosols in air at a 10 Hz pulse repetition rate. Na fluorescence was observed remotely at a distance of 16 m using a 318 mm diameter Newtonian telescope, a spectrometer, and an intensified CCD camera. These results show the possibility of remote measurement of the constituents of atmospheric particles, such as aerosols, clouds, and toxic materials, by LIBS-lidar using femtosecond terawatt laser pulses. 相似文献
92.
Efficient monocyclic 1,2-diazepine formation via a tandem electrocyclization reaction of cyclobutenones with lithiodiazoacetate is demonstrated. The reaction proceeds through an oxy anion-accelerated 4π-ring opening of cyclobutene followed by an 8π-ring closure of the resultant oxy anion-substituted diazo-diene under mild conditions to furnish a 1,2-diazepine via formal diazomethylene insertion into the C-C bond of cyclobutenone. 相似文献
93.
Takuya Yokosaka Akinari Hamajima Tetsuhiro Nemoto Yasumasa Hamada 《Tetrahedron letters》2012,53(10):1245-1248
We developed a novel method for the asymmetric synthesis of highly functionalized γ-lactams through an organocatalytic aza-Michael–Michael reaction cascade using fumaric acid amide esters as multi-reactive substrates. Using chiral primary or secondary amine organocatalysts, we obtained two types of γ-lactams with three contiguous chiral centers in moderate to good yield with excellent enantioselectivity and diastereoselectivity. 相似文献
94.
Peter C. Kunz Indre Thiel Anna Louisa Noffke Guido J. Reiß Fabian Mohr Bernhard Spingler 《Journal of organometallic chemistry》2012,697(1):33-40
A variety of piano-stool complexes of cyclopentadienyl ruthenium(II) with imidazole-based PN ligands have been synthesized starting from the precursor complexes [CpRu(C10H8)]PF6, [CpRu(NCMe)3]PF6 and [CpRu(PPh3)2Cl]. PN ligands used are imidazol-2-yl, -4-yl and -5-yl phosphines.Depending on the ligand and precursor different types of coordination modes were observed; in the case of polyimidazolyl PN ligands these were κ1P-monodentate, κ2P,N-, κ2N,N- and κ3N,N,N- chelating and μ-κP:κ2N,N-brigding. The solid-state structures of [CpRu(1a)2Cl ]·H2O (5.H2O) and [{CpRu(μ-κ2-N,N-κ’1-P-2b)}2](C6H5PO3H)2(C6H5PO3H2)2, a hydrolysis product of the as well determined [{CpRu(2b)}2](PF6)2.2CH3CN (7b.2CH3CN) were determined (1a = imidazol-2-yldiphenyl phosphine, 2b = bis(1-methylimidazol-2-yl)phenyl phosphine, 3a = tris(imidazol-2-yl)phosphine). Furthermore, the complexes [CpRu(L)2]PF6 (L = imidazol-2-yl or imidazol-4-yl phosphine) have been screened for their catalytic activity in the hydration of 1-octyne. 相似文献
95.
H Nagase S Imaide T Yamada S Hirayama T Nemoto N Yamaotsu S Hirono H Fujii 《Chemical & pharmaceutical bulletin》2012,60(8):945-948
On the basis of the three-dimensional pharmacophore model of opioid κ agonists, we simplified the structure of nalfurafine (selective κ agonist) to find the essential structural moieties for binding the opioid receptors, especially κ receptor type. As a result, we found that the trans-fused decahydroisoquinoline derivatives without a phenol ring bound the opioid receptor in micromolar order and that both the amide side chain and the nitrogen substituted by the cyclopropylmethyl group were indispensable moieties for eliciting the κ selectivity. The simple decahydroisoquinoline without amide side chain also bound the opioid receptor without receptor type selectivity, suggesting that the message-address concept would be applicable to even these simple derivatives. These findings that the simple decahydroisoquinoline derivatives showed the affinities for the opioid receptors, especially some of the compounds showed κ selectivity, are the first example in the opioid field. 相似文献
96.
97.
A. Uedono T. Ohdaira R. Suzuki T. Mikado S. Fukui S. Kimura H. Miyamoto H. Nemoto 《Journal of Polymer Science.Polymer Physics》2004,42(2):341-346
The volume and depth distributions of open spaces in photoresist films designed for ArF‐excimer laser light exposure were studied with monoenergetic positron beams. We measured the Doppler broadening spectra of the annihilation radiation and lifetime spectra of positrons for acrylate and cyclic olefin‐co‐maleic anhydride (COMA) polymers spin‐coated onto Si wafers with methyl amyl ketone, cyclohexanone, and propylene glycol methyl ether acetate solvents. The volume of open spaces in both prebaked acrylate and COMA films was estimated to be 0.12 nm3. The volume of open spaces in acrylate films decreased up to 20% by postexposure baking, but no large change was observed for COMA films. The decrease in the open volume was attributed to the removal of large molecules (adamantyl) from flexible main chains after the chemically amplified reaction of acrylate. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 341–346, 2004 相似文献
98.
99.
For scalar diffusion models with unknown drift function asymptotic equivalence in the sense of Le Cam's deficiency between
statistical experiments is considered under long-time asymptotics. A local asymptotic equivalence result is established with
an accompanying sequence of simple Gaussian shift experiments. Corresponding globally asymptotically equivalent experiments
are obtained as compound experiments. The results are extended in several directions including time discretisation. An explicit
transformation of decision functions from the Gaussian to the diffusion experiment is constructed.
The authors acknowledge the financial support provided through the European Community's Human Potential Programme under contract
HPRN-CT-2000-00100, DYNSTOCH 相似文献
100.
Shinzo Kano Tsutomu Yokomatsu Hajime Nemoto Shiroshi Shibuya 《Tetrahedron letters》1985,26(12):1531-1534
A high diastereoselective synthesis of 6-hydroxy-4a-aryl--decahydroisoquinoline derivatives was achieved by an application of N-acyliminium ion-induced polyene cyclization procedure. 相似文献