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91.
Gerasko OA Mainicheva EA Naumova MI Neumaier M Kappes MM Lebedkin S Fenske D Fedin VP 《Inorganic chemistry》2008,47(19):8869-8880
Sandwich-type lanthanide complexes with macrocyclic ligand cucurbit[6]uril (C 36H 36N 24O 12, CB[6]) were synthesized under hydrothermal conditions from aqueous solutions of lanthanide(III) bromides, CB[6], and 4-cyanopyridine. According to X-ray analysis (Ln = La, Pr, Dy, Ho, Er, and Yb), the compounds with different structural types of lanthanide cores have a common fragment where the tetranuclear hydroxo complex is sandwiched between two macrocycles {(IN@CB[6])Ln 4(mu 3-OH) 4(IN@CB[6])} (6+) (IN = isonicotinate). The photoluminescence (for Ln = Eu) and Fourier transform ion cyclotron resonance mass spectra (for Ln = Pr, Dy, and Er) were studied. The compounds are used for the first time as precursors for the synthesis of lanthanide-silver heterometallic coordination polymers. The chainlike crystal structure of polymers (Ln = La, Pr, and Dy) is constituted by the sandwich complexes linked via the coordination of IN nitrogen atoms to the silver atoms. 相似文献
92.
93.
V. Logvinenko T. Mitkina V. Drebushchak V. Fedin 《Journal of Thermal Analysis and Calorimetry》2011,105(1):103-106
The thermal decomposition of hydrated cucurbit[8]uril C48H48N32O16·20H2O (CB[8]) and the inclusion compound of cucurbit[8]uril with cobalt(III) complex {trans-[Co(en)2Cl2]@CB[8]}Cl·17 H2O was studied in the inert atmosphere by TG, TM, and DSC methods. The dehydration of (C48H48N32O16)·20H2O (at 320–390 K), and the decomposition of cucurbituril itself (at 620–720 K) are accompanied by a decrease in the sample
volume. The inclusion compound loses water molecules at 320–380 K; dehydration is accompanied by an increase in the sample
volume. The decomposition (pyrolisis) of the anhydrous compound takes place at 620–720 K; the decomposition is forestalled
by a continued increase in the sample volume with an endothermic peak (490–600 K), and only the mass loss (620–720 K) is accompanied
by a decrease in the sample volume. The included guest complex does not lose amines until the decomposition process is complete;
the previously observed increase in the sample volume is explained by the expansion of cavitand molecules due to a distortion
of the included [Co(en)2Cl2]+ complex on heating. 相似文献
94.
E. V. Tret’yakov V. G. Vasil’ev A. S. Bogomyakov G. V. Romanenko M. V. Fedin I. S. Antipin S. E. Solov’eva A. I. Konovalov R. Z. Sagdeev V. I. Ovcharenko 《Russian Chemical Bulletin》2013,62(2):543-547
A reaction of calix[4]arene tetraaldehyde with 2,3-bis(hydroxyamino)-2,3-dimethylbutane in DMF resulted in the corresponding 1,3-dihydroxyimidazolidine tetraadduct, whose oxidation gave a calix[4]arene (1,3-alternate) bearing four nitronyl nitroxyl-containing substituents at the upper rim. 相似文献
95.
M. S. Zavakhina D. G. Samsonenko D. N. Dybtsev M. P. Yutkin A. V. Virovets V. P. Fedin 《Russian Chemical Bulletin》2013,62(3):716-721
Chiral metal-organic coordination polymers [Co2(sacch)2]·1/2H2O·CH3OH (1), [Cu(sacch)(H2O)2]·3H2O (2), and [Mg(H2O)3(sacch)] (3) (H2sacch is d-saccharic acid) were synthesized from aqueous or water-methanol solutions of potassium hydrogen saccharate and a salt of the corresponding metal. The compositions and structures of the resulting compounds were determined by single-crystal X-ray diffraction and confirmed by X-ray powder diffraction, IR spectroscopy, thermogravimetry, and elemental analysis. 相似文献
96.
T. V. Mitkina D. Yu. Naumov O. A. Gerasko F. M. Dolgushin C. Vicent R Llusar M. N. Sokolov V. P. Fedin 《Russian Chemical Bulletin》2004,53(11):2519-2524
The inclusion compound of macrocyclic cavitand cucurbit[8]uril (CB[8]) with the nickel(II) complex containing the tetraazamacrocyclic ligand cyclam, {[Ni(cyclam)]@CB[8]}Cl2··16H2O (1), and the inclusion compounds of CB[8] with the copper(II) bis-ethylene-diamine complex, {trans-[Cu(en)2(H2O)2]@CB[8]}Cl2·{CB[8]}·42H2O (2a) and {trans-[Cu(en)2(H2O)2]@CB[8]}Cl2·17H2O (2b), were synthesized and characterized by X-ray diffraction analysis, IR and ESR spectroscopy, and electrospray mass spectrometry. Guest—host inclusion compounds can be directly synthesized starting from a metal complex and cucurbit[8]uril, as was exemplified by the preparation of compounds 2a and 2b.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2414–2419, November, 2004. 相似文献
97.
Vadim A. Dubskikh Anna A. Lysova Denis G. Samsonenko Alexander N. Lavrov Konstantin A. Kovalenko Danil N. Dybtsev Vladimir P. Fedin 《Molecules (Basel, Switzerland)》2021,26(5)
Three new 3D metal-organic porous frameworks based on Co(II) and 2,2′-bithiophen-5,5′-dicarboxylate (btdc2−) [Co3(btdc)3(bpy)2]·4DMF, 1; [Co3(btdc)3(pz)(dmf)2]·4DMF·1.5H2O, 2; [Co3(btdc)3(dmf)4]∙2DMF∙2H2O, 3 (bpy = 2,2′-bipyridyl, pz = pyrazine, dmf = N,N-dimethylformamide) were synthesized and structurally characterized. All compounds share the same trinuclear carboxylate building units {Co3(RCOO)6}, connected either by btdc2– ligands (1, 3) or by both btdc2– and pz bridging ligands (2). The permanent porosity of 1 was confirmed by N2, O2, CO, CO2, CH4 adsorption measurements at various temperatures (77 K, 273 K, 298 K), resulted in BET surface area 667 m2⋅g−1 and promising gas separation performance with selectivity factors up to 35.7 for CO2/N2, 45.4 for CO2/O2, 20.8 for CO2/CO, and 4.8 for CO2/CH4. The molar magnetic susceptibilities χp(T) were measured for 1 and 2 in the temperature range 1.77–330 K at magnetic fields up to 10 kOe. The room-temperature values of the effective magnetic moments for compounds 1 and 2 are μeff (300 K) ≈ 4.93 μB. The obtained results confirm the mainly paramagnetic nature of both compounds with some antiferromagnetic interactions at low-temperatures T < 20 K in 2 between the Co(II) cations separated by short pz linkers. Similar conclusions were also derived from the field-depending magnetization data of 1 and 2. 相似文献
98.
Yao W. Zhang Z. Y. Xu B. T. Yu X. L. Li X. Y. Fedin V. P. Gao E. J. 《Journal of Structural Chemistry》2022,63(8):1313-1322
Journal of Structural Chemistry - A new novel Cu(II) compound formulated as Cu(C4N6H4)2Cl2 (1) (C4N6H4 = 1H-3,4′-bi-1,2,4-triazole) is successfully synthesized by a... 相似文献
99.
Andrienko I. V. Kovalenko E. A. Samsonenko D. G. Fedin V. P. 《Russian Chemical Bulletin》2020,69(11):2113-2120
The crystals of the compounds [Na4(H2O)14CB[6]](bdc)2 · 13H2O (1) and [Na6(H2O)19CB[6]]-(bdc)3 ·15H2O (2) were obtained by heating an aqueous solution of sodium terephthalate (Na2bdc) and cucurbit[6]uril (CB[6]). According to the single-crystal X-ray diffraction data, the sodium aqua complexes and cucurbit[6]uril molecules form chains (in structure 1) and layered metal-organic frameworks (in structure 2). The structures of the sodium aqua complexes [Na3(H2O)10]3+ in 1 and [Na6(H2O)19]3+ in 2 have been previously unknown. When submitted to ultraviolet radiation, crystals of 1 and 2 exhibit luminescence with an emission maximum at 428 and 434 nm, respectively.
相似文献100.
V. P. Fedin D. G. Samsonenko A. V. Virovets I. V. Kalinina D. Yu. Naumov 《Russian Chemical Bulletin》2000,49(1):19-25
Four new chalcogenide molybdenum and tungsten cubane clusters (NH4)6[M4Q4(CN)12]·6H2O (M=Mo or W; Q=S or Se) were prepared by high-temperature reactions of the triangular M3O7Br4 complexes with KCN at 430 °C followed by crystallization from aqueous solutions of ammonium acetate. The molecular and crystal
structures of (NH4)6[Mo4S4(CN)12]·6H2O, (NH4)6[W4S4(CN)12]·6H2O, and (NH4)6[W4Se4(CN)12]·6H2O were established by X-ray diffraction analysis. The mixed-valence cubane clusters are diamagnetic and isostructural and
have the symmetryT
d
. The clusters were characterized by IR and electronic spectroscopy. The data of cyclic voltammetry demonstrated that the
[M4Q4(CN)12]
n− clusters exist in three oxidation states from the most oxidized (n=6; 10 cluster electrons) to the most reduced electron-precise 12-electron species (n=8).
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 18–24, January, 2000. 相似文献