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1.
Matveeva E. D. Podrugina T. A. Grishin Yu. K. Tkachev V. V. Zhdankin V. V. Aldoshin S. M. Zefirov N. S. 《Russian Journal of Organic Chemistry》2003,39(4):536-541
A mixed phosphonium-iodonium ylide, phenyliodoniumethoxycarbonylmethylenetriphenylphosphorane borofluoride, was synthesized. Its structure was established by means of X-ray diffraction analysis. Temperature dependence of 1H, 13C, and 31P spectra of the ylide synthesized was investigated. A dynamic equilibrium between Z and E-isomers was observed. 相似文献
2.
3.
4.
O. S. Filipenko S. M. Aldoshin G. V. Shilov N. I. Makarova V. A. Kharlanov M. I. Knyazhanskii 《Russian Chemical Bulletin》1995,44(2):287-292
The molecular structures of the initial compounds and the products of photocyclization involving amino and azomethine groups in perchlorates ofN-amino (1) andN-azomethine (2) derivatives of 2,4,6-triphenylpyridinium cations were studied. Cations1 and2 have an essentially non-coplanar arrangement of the -Ph rings, and the product of photocyclization of2, cation3, is characterized by a flattened structure. It was found that the orientation of the lone electron pair of the N atom with respect to one of the planes of the -Ph rings in molecule1 is more favorable for monocyclization involving the amino group. The structure of molecule2 allows two routes of the photoreaction,viz., O N proton transfer and monocyclization with an -Ph ring. However, the structural features of molecule2 are more favorable for photocyclization.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 296–301, February, 1995. 相似文献
5.
I. I. Chuev S. M. Aldoshin O. A. Kozina A. D. Dubonosov E. N. Shepelenko V. A. Bren' V. I. Minkin 《Russian Chemical Bulletin》1992,41(12):2230-2233
X-ray structural analysis was used to determine the molecular and crystal structure of 2-(N-benzyl-N-phenylhydrazinoethylidene)-3-(2H)-benzo[b]thiophenone. The crystals are monoclinic, the space group isC2/c,a=16.022(6),b=11.202(3),c=22.111(4) Å, =81.08(3)°, and andZ=8. It was shown that the ability of hydrazones of a similar class to exhibit photochromic properties is a function of the steric stresses in the molecules and their confirmation.Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences, 142432 Chernogolovka. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 12, pp. 2805–2809, December, 1992. 相似文献
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7.
V. P. Rybalkin E. N. Shepelenko V. V. Tkachev G. V. Shilov S. K. Balenko A. V. Tsukanov L. L. Popova A. D. Dubonosov S. M. Aldoshin V. A. Bren’ V. I. Minkin 《Russian Chemical Bulletin》2006,55(1):101-105
New photochromic fulgide, viz., 4-{1-[2-(anthracen-9-yl)-5-methyloxazol-4-yl]ethylidene}-3-isopropylidenetetrahydrofuran-2,5-dione, with fluorescent properties
was synthesized. Studies by electronic, IR, and 1H NMR spectroscopy and X-ray diffraction demonstrated that this fulgide exists in the Z form. Light irradiation of its solutions at a wavelength of 365 nm causes Z/E isomerization giving rise to the thermally stable cyclic form. The latter is transformed into the starting E isomer under light irradiation at λ = 436 nm.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 97–101, January, 2006. 相似文献
8.
V. N. Komissarov L Yu Ukhin V. A. Kharlanov V. A. Lokshin E. Yu Bulgarevich V. I. Minkin O. S. Filipenko M. A. Novozhilova S. M. Aldoshin L. O. Atovmyan 《Russian Chemical Bulletin》1992,41(10):1875-1883
Mannich bases exhibiting photo- and thermochromic properties in solutions were synthesized from 3,5-di-tert-butyl-4-hydroxybenzaldehyde and 2-naphthols. An investigation of an acetyl derivative of methylenequinone, modeling a product of photo- and thermochromic transformations, proved that the color change of solutions of the Mannich bases is due to reversible dissociation into colored methylenequinones and morpholine. On the basis of data of x-ray diffraction analysis of one of the Mannich bases, characteristics of their molecular structure were determined, and reasons were stated for their effect on the dissociation mechanism. 相似文献
9.
This paper studies the crystal structure of new substituted light-sensitive azomethine N-oxides (nitrones): C-2′-(o-oxyphenyl)vinyl-N-p-methylphenyl
nitrone (1), C-2′-(2″-oxy-5″-bromophenyl)vinyl-N-p-methylphenyl nitrone (2), C-2′-(2″-oxy-5″-bromophenyl)-vinyl-N-phenyl nitrone
(3), and C-2′-(o-oxyphenyl)vinyl-N-methyl nitrone (4). In contrast to the compounds studied earlier [1, 2], C-2′-(β-oxy-α-naphthyl)vinyl-N-p-methylphenyl
nitrone (5), C-2′-(β-oxy-α-naphthyl)vinyl-N-phenyl nitrone (6), C-2′-(o-oxyphenyl) vinyl-N-phenyl nitrone (7), and C-2′-(o-oxyphenyl)vinyl-N-p-bromophenyl
nitrone (8), the nitrones studies in this work have anti-rather than syn-orientations of the nitrone and hydroxyl groups.
Due to this spatial arrangement of the proton-donating hydroxyl and proton-accepting nitrone groups, molecules in crystals
1–4 are bonded by intermolecular hydrogen bonds (IHB) to form chains but not centrosymmetric dimeric associates (CDA). Two
types of chain arrangements were revealed: “head-to-tail” and “head-to-tail, tail-to-head”. It is shown that the introduction
of an alkyl substituent instead of an aryl one at the nitrogen atom of the nitrone group in 4 leads to a change in the geometry
of the IHB in the H-associate. It is proven that the hydroxyl proton can undergo an intermolecular O→O transfer in the chain
of hydrogen bonds in crystals 1–4, which can give rise to photochemical transformations in these crystals.
Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 37, No. 2, pp. 349–362, March–April, 1996.
Translated by L. Smolina 相似文献
10.
P. E. Matkovskii V. D. Makhaev S. M. Aldoshin L. N. Russiyan G. P. Startseva Yu. I. Zlobinskii L. N. Raspopov I. V. Sedov 《Polymer Science Series A》2007,49(5):496-502
New supported metallocene catalysts based on tetrakis(cyclopentadienyl)zirconium + methylaluminoxane (MAO) were prepared and tested for ethylene polymerization and copolymerization with hexene-1. It was shown that silica gel of the Davison 952 brand is the best support for such catalysts. The maximum catalyst activity was achieved on the support impregnated with the (C5H5)4Zr-MAO complex. The addition of hexene-1 into the liquid phase resulted in acceleration of polymerization and an increase in the product yield. The morphological, rheological, and other properties of polymers and copolymers were studied. The test catalytic system can be used for manufacture of low-, medium-, and high-density polyethylenes with various stress-strain characteristics. 相似文献