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451.
Electrosyntheses of high quality poly(5-methylindole) films in mixed electrolytes of boron trifluoride diethyl etherate and diethyl ether 总被引:1,自引:0,他引:1
High quality poly(5-methylindole) (P5MeI) films, especially with good fluorescence properties, were synthesized electrochemically by direct anodic oxidation of 5-methylindole in boron trifluoride diethyl etherate (BFEE) containing additional 50% diethyl ether (EE) (by volume). The oxidation potential onset of 5-methylindole in this medium was measured to be only 0.84 V vs. SCE, which was much lower than that determined in acetonitrile + 0.1 mol L−1 TBATFB (1.08 V vs. SCE). P5MeI films obtained from this medium showed good electrochemical behavior and good thermal stability with conductivity of 10−2 S cm−1, indicating that BFEE was a better medium than acetonitrile for the electrosyntheses of P5MeI films. Dedoped P5MeI films were thoroughly soluble in strong polar solvent such as dimethyl sulfoxide (DMSO). 1H NMR spectroscopy and FT infrared spectrum of dedoped P5MeI films strongly suggested that the monomers were linked via the positions 2 and 3. Fluorescent spectral studies indicated that P5MeI was a good violet-blue light emitter with the excitation and emission wavelength of 310 nm and 418 nm, respectively. To the best of our knowledge, this is the first case that 5-methyl group substituted polyindole films with good fluorescence properties can be electrodeposited. 相似文献
452.
Guilio Alberti Umberto Costantino Fabio Marmottini Giovanni Perego 《Journal of inclusion phenomena and macrocyclic chemistry》1989,7(5):549-560
Many primary diamines H2N(CH2)nNH2 (all the members withn ranging from 0 to 12 with the exception ofn =I 1) have been intercalated within the phosphate regions of layered zirconium phosphate-phosphite. As a general rule, intercalation occurs in two steps that are not well differentiated. The first one leads to intercalation compounds in which the diamines are arranged with their alkyl chain oriented parallel to the layers; the second one to the fully intercalated compounds. These latter compounds have composition Zr(HPO4)0.7(HPO3)1,3-yNH2(CHn2)·NH2, withy ranging from 0.36 to 0.49 depending on the nature of the diamine. Not all the diamine molecules are thus diprotonated and they show a tendency to reach a y value of 0.5, corresponding to the total occupancy of the crystal sites available for intercalation. Diamines are arranged as a monolayer of extended molecules and an evident even-odd alternation of the interplanar spacing has been observed.A comparison with the intercalation of-zirconium phosphate for the same diamines is also made. 相似文献
453.
Holger Wessolowski Gary L. Gard Gerd-Volker Röschenthaler 《Journal of fluorine chemistry》1996,80(2):149-152
The reaction of 3,3-bis(trifluoromethyl)-1,1,2,4,4,4-hexafluoro-1-butylene and nonafluoro-n-butoxy-1,1,2-trifluoroethylene with tris(trimethylsilyl)phosphite gave fluorotrimethylsilane and the respective (Z)-alkenylbis(trimethylsilyl)phosphonates. In one case hydrolysis afforded the free phosphonic acid (CF3)3CCF = CFP(O) (OH)2. Using tri-n-butylphosphine and boron trifluoride etherate, 3,3-bis(trifluoromethyl)-1,1,2,4,4,4-hexafluoro-1-butylene and nonafluoro-n-butoxy-1,1,2-trifluoroethylene were converted into the corresponding phosphonium tetrafluoroborates, which when reacted further with iodine in the presence of Na2CO3 gave the iodo derivatives (CF3)3CCF = CFI and C4F9OCF = CFI. 相似文献
454.
在高钙及不同浓度枸橼酸二乙酯(Et2Cit)、枸橼酸钠(Na3Cit)和膦甲酸钠(PFA)存在下培养小鼠血管平滑肌细胞(MOVAS)14 d,分别通过茜素红染色、免疫荧光和annexin V染色检测细胞的分化、凋亡和细胞钙沉积量,研究了Et2Cit、Na3Cit和PFA对高钙诱导MOVAS细胞钙化的抑制效果及可能的作用机制。结果表明,Et2Cit、Na3Cit和PFA均能减少高钙诱导的MOVAS钙化,减少细胞外钙化斑块和钙沉积量。这些抑制剂均能抑制平滑肌细胞向成骨样细胞表型转化,导致向成骨细胞转化的标记物碱性磷酸酶(ALP)活性降低。抑制效果均存在浓度依赖性。当抑制剂浓度相同时,其抑制效果从大到小为:PFA > Na3Cit > Et2Cit。低浓度的Et2Cit和Na3Cit可通过减少细胞凋亡来抑制钙化,但高浓度的Et2Cit、Na3Cit和PFA自身具有毒性,这增加了细胞的凋亡。作为血液抗凝剂的Et2Cit和Na3Cit可以有效地抑制MOVAS的钙化。 相似文献
455.
P. V. Verdes M. M. Mato J. L. Legido E. Jiménez M. I. Paz Andrade 《Journal of Thermal Analysis and Calorimetry》2007,88(2):613-616
Excess molar enthalpies
of the ternary system {x
1
p-xylene+x
2decane+(1–x
1–x
2)diethyl
carbonate} and the involved binary mixtures {p-xylene+(1–x)decane}, {xp-xylene+(1–x)diethyl carbonate} and {xdecane+(1–x)diethyl carbonate} have been determined at the
temperature of 298.15 K and atmospheric pressure, over the whole composition
range, using a Calvet microcalorimeter. The experimental excess molar enthalpies H
m
E
are positive for all the binary systems studied over the whole composition
range. Excess molar enthalpy for the ternary system is positive as well, showing
maximum values at x
1=0, x
2=0.4920, x
3=0.5080, H
m,123
E=1524
J mol–1. 相似文献
456.
A. Yu. Volkonsky V. R. Polishchuk E. M. Kagramanova E. I. Mysov N. E. Mysova M. Yu. Antipin Yu. T. Struchkov 《Russian Chemical Bulletin》1994,43(1):80-83
The 1:1 adducts of diethyl and ,,','-tetrakis(trifluoromethyl)divinyl ether (1),i.e., 3,5-(ee)-bis[2,2,2-trifluoro-1-(trifluoromethyl)ethyl]-2,6-dimethyl-1,4-dioxane (2) (3 isomers) and 4-ethoxy-1,1,1-trifluoro-2-trifluoromethyl-3-[3,3,3-trifluoro-2(trifluoromethyl)propenyloxy]pentane (3), have been obtained by UV-irradiation of a solution of divinyl ether1 in diethyl ether. The X-ray structural investigation of the all-(e)-isomer of dioxane (2) has been carried out.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 85–88, January, 1994. 相似文献
457.
The Perkow reaction of triethyl phosphite and β-alkoxyvinyl trihalogenomethyl ketones, which have common acyclic or cyclic structural fragment: -O-CC-C(O)CX2Cl, yielded dienyl phosphates: -O-CC-C[OP(O)(OEt)2]CX2 where X = F or Cl, whereas γ-bromo-β-methoxy-α,β-unsaturated trifluoromethyl ketone CF3C(O)CHC(OMe)CH2Br gave diene CF3C[OP(O)(OEt)2]CH-C(OMe)CH2. 相似文献
458.
D. R. Latypova L. I. Vlasova N. Z. Baibulatova A. N. Lobov L. V. Spirikhin V. A. Dokichev 《Chemistry of Heterocyclic Compounds》2008,44(8):996-1002
Unnatural amino acids containing the 3,7-diazabicyclo[3,3,1]nonane unit were synthesized in one step by the reaction of diethyl
3-oxoglutarate, bis(methoxycarbonylmethyl) sulfone, with formaldehyde and primary amino acids under conditions of the Mannich
reaction.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, 1236–1244, August, 2008. 相似文献
459.
A new fluorinated gallium phosphite, Ga3F2(2,2′-bipy)2(HPO3)2(H1.5PO3)21, which is the first layered gallium phosphite with neutral framework, has been hydrothermally synthesized in the presence of 2,2′-bipyridine (2,2′-bipy) acting as a ligand. The as-synthesized product was characterized by single-crystal X-ray diffraction, powder X-ray diffraction, IR spectroscopy, thermogravimetric analysis (TGA), ICP-AES and elemental analyses and fluorescent spectrum. Single-crystal X-ray diffraction analysis reveals that compound 1 crystallizes in the monoclinic space group C2/c (No. 15) with cell parameters a=17.633(3) Å, b=9.883(2) Å, c=16.793(3) Å, β=109.88(3)°, V=2752.1(9) Å3 and Z=4. The construction of two-dimensional (2D)-layered structure in compound 1 may be viewed as the assembly of heptameric building unit, which is the first to be found in gallium phosphate/phosphite. The heptameric building unit exists in two types of configuration, which alternately connect through oxygen atoms from HPO3 pseudo-pyramids to form a layer with 10-membered ring windows viewed along the a-axis. The adjacent layers are stably packed together and exhibit interesting three-dimensional (3D) supramolecular array via π-π interactions of the 2,2′-bipy groups. Additionally, compound 1 shows strong fluorescent property in solid state at room temperature. 相似文献
460.
T. V. Golovko N. P. Solov’eva O. S. Anisimova O. B. Smirnova M. I. Evstratova S. S. Kiselev V. G. Granik 《Russian Chemical Bulletin》2008,57(1):177-185
Condensation of indolin-2-one (oxindole) lactim ether with malononitrile leads to 2-dicyanomethylidene-2,3-dihydroindole,
the reaction of which with dimethylformamide diethyl acetal (or with triethyl orthoformate) and the subsequent cyclization
afford 4-cyanopyrido[4,3- b]indoles (γ-carbolines). 3-Amino-4-cyanopyrido[4,3-b]indole was used in the synthesis of substituted pyrimido[4,5-c]-γ-carbolines.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 171–179, January, 2008. 相似文献