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91.
Ter(9,9-diarylfluorene)s: highly efficient blue emitter with promising electrochemical and thermal stability 总被引:4,自引:0,他引:4
Wong KT Chien YY Chen RT Wang CF Lin YT Chiang HH Hsieh PY Wu CC Chou CH Su YO Lee GH Peng SM 《Journal of the American Chemical Society》2002,124(39):11576-11577
Novel ter(9,9-diarylfluorene)s were synthesized by a Suzuki-coupling reaction of 2-bromofluorene (1) and 2,7-fluorenediboronic ester derivatives (3) with high isolated yields (63-86%). The X-ray structure analysis of ter(9,9'-spirobifluorene) (4aa) revealed that the conjugated chromophore adopts a helical conformation. This conformation effectively releases the steric interaction between the fluorene moieties and prevents inter-chromophore interactions. The introduction of aryl groups at the C9 position of fluorene was highly beneficial to the thermal and morphological stability of these oligomers. These terfluorenes exhibit intense blue fluorescence with excellent quantum yields both in solution ( approximately 100%) and in solid state (66-90%), and possess interesting reversible redox properties. Highly efficient blue light-emitting OLED devices were fabricated using 4aa and 4cc as emitters as well as hole transporters. The devices exhibit low turn-on voltage ( approximately 3 V) and high EL external quantum efficiency (2.5-3%). 相似文献
92.
Fang-Yuan Lee Yu-Ju Chen Gene-Hsiang Lee Jih Ru Hwu 《Journal of organometallic chemistry》2005,690(2):441-449
The reaction of Os3(CO)12 with an excess of 1-hydroxypyridine-2-thione and Me3NO gives three mononuclear osmium complexes Os(CO)2(η2-SC5H4N(O))2 (1), Os(CO)2(η2-SC5H4N(O))(η2-SC5H4N) (2), and Os(CO)2(η2-SC5H4N)2 (3). The results of single-crystal X-ray analyses reveal that complex 1 contains two O,S-chelate pyridine-2-thione N-oxide (PyOS) ligands, whereas complex 2 contains one O,S-chelate PyOS and one N,S-chelate pyridine-2-thiolate group. The unique structure of 2 provides evidence of the pathway for this transformation. When this reaction was monitored by 1H NMR spectroscopy the triosmium complexes Os3(CO)10(μ-H)(μ-η1-S-C5H4N(O)) (4) and Os3(CO)9(μ-H)(μ-η1:η2-SC5H4N(O)) (5) were identified as intermediates in the formation of the mononuclear final products 1-3. The proposed pathway is further supported by the observation of several dinuclear osmium intermediates by electrospray ionization mass spectrometry. In addition, the reaction of Os3(CO)12 with 1-hydroxypyridine-2-thione in the absence of Me3NO at 90 °C generated mononuclear complex 2 as the major product along with smaller amounts of complexes 1 and 3. These results suggest that the N-oxide facilitates the decarbonylation reaction. Crystal data for 1: monoclinic, space group C2/c, a = 26.9990(5) Å, b = 7.6230(7) Å, c = 14.2980(13) Å, β = 101.620(2)°, V = 2882.4(4) Å3, Z = 8. Crystal data for 2: monoclinic, space group C2/c, a = 5.7884(3) Å, b = 13.9667(7) Å, c = 17.2575(9) Å, β = 96.686(1)°, V = 1385.69(12) Å3, Z = 4. 相似文献
93.
Benzoylformyl complexes CpMo(COCOPh)(CO)3 (1) and CpFe(COCOPh)(CO)2 (2) were prepared by the reactions of [CpMo(CO)3]? and [CpFe(CO)2]? ions with PhCOCOCl, respectively. The single-crystal structure of complex 1 has been determined by X-ray diffraction with crystal data: P21/c, a = 6.674 (3) Å, b = 13.301 (4) Å, c= 16.903(6) Å, β = 90.82 (5)°,V = 1500(1) Å3, Z = 4. Least-squares refinement on 894 reflections with I ≥ 2.0 σ(I) led to R = 0.041, RW = 0.042. Complex 1 contains a near perpendicular s-trans oxalyl moiety in the benzoylformyl ligand with the torsional angle O4-C4-C5-O5 being 104 (1)°. The iron complex suffers spontaneous decarbonylation at 25 °C to yield CpFe(COPh)(CO)2. 相似文献
94.
Reaction of W(η2-PhCCPh)3(NMe3) (1) and Ph2PCCPPh2 (dppa) produces W(η2-PhCCPh)3(η1-Ph2PCCPPh2) (2), which contains a pendant phosphine group. Treatment of 2 with W(CO)4(NCMe)2 yields [W(η2-PhCCPh)3](μ,η2-Ph2PCCPPh2)[W(CO)4(NCMe)] (3). Compound 2 reacts with Os3(CO)10(NCMe)2 to afford Os3(CO)10[(μ,η2-Ph2PCCPPh2)W(η2-PhCCPh)3]2 (4), and reacts with Ru3(CO)9(NCMe)3 to afford Ru3(CO)9[(μ,η2-Ph2PCCPPh2)W(η2-PhCCPh)3]3 (5). The crystal structures of 2 and 3 are determined by an X-ray diffraction study. 相似文献
95.
Kom-Bei Shiu Shin-Jay Yu Yu Wang Gene-Hsiang Lee 《Journal of organometallic chemistry》2002,650(1-2):37-42
Treatment of [Ru2(CO)4(MeCN)6][BF4]2 or [Ru2(CO)4(μ-O2CMe)2(MeCN)2] with uni-negative 1,1-dithiolate anions via potassium dimethyldithiocarbamate, sodium diethyldithiocarbamate, potassium tert-butylthioxanthate, and ammonium O,O′-diethylthiophosphate gives both monomeric and dimeric products of cis-[Ru(CO)2(η2-(SS))2] ((SS)−=Me2NCS2− (1), Et2NCS2− (2), tBuSCS2− (3), (EtO)2PS2− (4)) and [Ru(CO)(η2-(Me2NCS2))(μ,η2-Me2NCS2)]2 (5). The lightly stabilized MeCN ligands of [Ru2(CO)4(MeCN)6][BF4]2 are replaced more readily than the bound acetate ligands of [Ru2(CO)4(μ-O2CMe)2(MeCN)2] by thiolates to produce cis-[Ru(CO)2(η2-(SS))2] with less selectivity. Structures 1 and 5 were determined by X-ray crystallography. Although the two chelating dithiolates are cis to each other in 1, the dithiolates are trans to each other in each of the {Ru(CO)(η2-Me2NCS2)2} fragment of 5. The dimeric product 5 can be prepared alternatively from the decarbonylation reaction of 1 with a suitable amount of Me3NO in MeCN. However, the dimer [Ru(CO)(η2-Et2NCS2)(μ,η2-Et2NCS2)]2 (6), prepared from the reaction of 2 with Me3NO, has a structure different from 5. The spectral data of 6 probably indicate that the two chelating dithiolates are cis to each other in one {Ru(CO)(η2-Et2NCS2)2}fragment but trans in the other. Both 5 and 6 react readily at ambient temperature with benzyl isocyanide to yield cis-[Ru(CO)(CNCH2Ph)(η2-(SS))2] ((SS)=Me2NCS2− (7) and Et2NCS2− (8)). A dimerization pathway for cis-[Ru(CO)2(η2-(SS))2] via decabonylation and isomerization is proposed. 相似文献
96.
Ray-Kuang Chiang Niang-Tsu ChuangChing-Shuei Wur Mong-Fu ChongChung-Rong Lin 《Journal of solid state chemistry》2002,166(1):158-163
A new hybrid organic-inorganic three-dimensional compound, [Co4(OH)2(H2O)2](C4H11N2)2[C6H2(CO2)4]2·3H2O 1, has been synthesized via hydrothermal reactions and characterized by single-crystal X-ray diffraction, infrared spectroscopy, thermogravimetric analysis, and magnetic techniques. Compound 1 crystallizes in the monoclinic space group P21/n (no. 14) with a=6.3029(9) Å, b=16.413(2) Å, c=17.139(2) Å, β=98.630(2)°, V=1735.0(4) Å3, Z=2. Compound 1 contains tetranuclear Co4(μ3-OH)2(H2O)2 clusters that are inter-linked by pyromellitate bridging ligands into a three-dimensional structure containing one-dimensional tunnels along the a-axis with water and pendant monoprotonated piperazine molecules in the center. The variable temperature magnetic susceptibility was measured from 2 to 300 K at 5000 Oe showing a predominantly anti-ferromagnetic interaction in 1, and the field dependence of magnetization was measured at 2, 5, 15, and 20 K indicating the competition of magnetic interactions in the tetranuclear centers. 相似文献
97.
98.
Whereas reaction of [PhCH2NMe3]2|Te6Fe8(CO)24] (1) in refluxing CH2CI2 forms Fe2(CO)6(μ0-) TeCH2Te), treatment of 1 with Ph2SnCl 2 or Mel gave the oxidation product Te2Fe3(CO)9. Oxidation of 1 with [Cu(CH3CN)4]BF4 afforded Te2Fe3(CO)9 in good yield. Cluster 1 was converted to [PhCH2NMe3][Te4Fe5(CO)14] (2) in MeOH/CH2Cl2 solution. Cluster 2 was structurally characterized by single-crystal X-ray diffraction and spectral methods. Complex 2 is composed of two Te2Fe2(CO)6 fragments linked by one Fe(CO)2 group. 2 crystallizes in the orthorhombic space group Pbcn with a = 13.351 (4) Å, b = 13.417 (4) Å, c = 26.077 (3) Å, V = 4671 (2) Å 3, Z = 4. 相似文献
99.
The reaction of diethylmagnesium dioxane adduct solution with 1,1,1,3,3,3-hexamethyldisilazan ((CH3)3SiNHSi(CH3)3) gives {[(CH3)3Si]2N}2MgO(CH2CH2)2OMg{N[Si(CH3)3]2}2 (1); this alkoxomagnesium silylamide in the solid state contains unprecedented three-coordinate magnesium and oxygen atoms. 相似文献
100.