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431.
分别以对溴苯甲酸和对碘苯甲酸为第一配体、含氮杂环(TPTZ和phen)为第二配体,以单一稀土Eu3+和Eu3+掺杂Gd3+、y3+为中心合成了12种配合物.对其进行了元素分析、紫外光谱、红外光谱、荧光激发和发射光谱的测定.推测化合物的组成分别为:(1)Eu(P- BrBA)3(TPTZ)·2H2 O; (2) Eu(P - IBA)3 (TPIZ)·2H2O;(3)Eu0.5Gd0.5 (P - BrBA)3 (TPTZ)·2H2O; (4) Eu0.5 Gd0.5(P- IBA)3(TPTZ)· 2H2O; (5) Eu0.5Y0.5(P - BrBA)3(TPTZ)· 2H2O;(6)Eu0.5Y0.5(P-IBA)3(TPTZ) · 2H2O;(7)Eu(P-BrBA)3(phen)· 2C2H5OH;(8)Eu(P- IBA)3(phen)· 2C2 H5 OH; (9) Eu0.5 Gd0.5(P- BrBA)3(phen)·2C2H5OH; (10) Eu0.5Gd0.5(P- IBA)3( phen).2C2H5OH;(11)Eu0.5Y0.5(P- BrBA)3(phen)·2C2H5OH和(12) Eu0.5Y0.5(P- IBA)3 (phen)·2C2H5 OH.卤代苯甲酸的羧基氧和稀土离子配位,TPTZ和phen的氮原子与稀土离子成键;配合物的形成对配体的共轭π-π*跃迁影响不大;几种不同的卤代苯甲酸铕配合物的发光强度有所差别,对溴苯甲酸配合物较强,中性配体TPTZ强于phen;掺钆、钇的铕配合物的荧光强度大于纯铕配合物,表明掺杂配合物并非简单配合物的混合,而是有一定混配配合物形成. 相似文献
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《分离科学与技术》2012,47(12):1941-1949
Studies on the solvent extraction and pertraction behavior of europium(III) was carried out from acidic feed solutions using N,N,N′,N′-tetra-2-ethylhexyl-3-oxapentane-diamide (T2EHDGA) in n-dodecane as the solvent. The nature of the extracted species from the solvent extraction studies conformed to Eu(NO3)3 · 3T2EHDGA which is in variance with the analogous Eu(III) – TODGA (linear homolog of T2EHDGA) extraction system. The transport behavior of Eu(III) was investigated from a feed containing 3.0 M HNO3 into a receiver phase containing 0.01 M HNO3 across a PTFE flat sheet supported liquid membrane (SLM) containing 0.2 M T2EHDGA in n-dodecane as the carrier solvent and 30% iso-decanol as the phase modifier. Effects of feed acidity, carrier extractant concentration, membrane pore size, and Eu concentration in the feed on the transport rates of Eu(III) were also investigated. Membrane diffusion coefficient (D o) for the pertracted species was calculated using the Wilke-Chang equation as 4.25 × 10?6 cm2 · s?1. The influence of Eu concentration on the flux was also investigated. The role of temperature on the transport rates was investigated and the thermodynamic parameters were calculated. 相似文献
437.
Two complexes [Eu2(2-TFMBA)6(2,2′-bipy)2]·2H2O (1) and Eu2(2-TFMBA)6(1,10-phen)2 (2) (2-TFMBA=2-(Trifluoromethyl) benzoate; 2,2′-bipy=2,2′-bipyridine; 1,10-phen= 1,10-phenanthroline) were synthesized by solvent method and determined by X-ray diffraction analysis. Complex 1 crystallizes in monoclinic system with space group P21/c, whereas complex 2 crystallizes in triclinic system with space group Pi. Both are binuclear molecules with an inversion center. In complex 1, two center Eu^3+ ions are linked together by four 2-TFMBA ligands in bidentate-bridging mode. Each Eu^3+ ion is eight-coordinated with six O atoms from five 2-TFMBA ligands and two N atoms from one 2,2′-bipy molecule. In complex 2, two center Eu^3+ ions are linked together by four 2-TFMBA ligands in two modes, namely, bidentate-bridging and tridentate-bridging. Each Eu^3+ ion is nine-coordinated with seven O atoms from five 2-TFMBA ligands and two N atoms from one 1,10-phen molecule. The two complexes both exhibited strong red fluorescence under ultraviolet light, and the ^5D0→^7Fj (j=0-4) transition emissions of Eu^3+ ion were observed in their emission spectra. 相似文献
438.
A new complex Eu2(PA)6(phen)2 was prepared with hydrothermal reaction using EuCl3.6H2O, phenylmalonic acid (H2phma), and 1, 10-phenanthroline (phen), where PA was the decarboxylated product of HEphma, phenylacetate. The crystal structure of the title complex was determined with the X-ray diffraction. The title complex was a binuclear molecule with an inversion center. Each Eu^3+ ion was nine-coordinated with two nitrogen atoms from one phen molecule and seven oxygen atoms from five PA ligands. The carboxylic groups were bonded to the Eu^3+ ion in three modes, the chelating bidentate, the bridging bidentate, and the bridging-chelating tridentate. The complex emits intense red fluorescence under ultraviolet light. The luminescence peaks correspond to the characteristic emission 5D0→7FJ (J=0-4) transitions of the Eu^3+ ion. 相似文献
439.
By heat treating the alkaline earth fluorosilicate glass, transparent glass ceramics containing alkaline earth fluoride nanocrystallites were prepared. The luminescence spectra and phonon sideband associated with the Eu3+:5D2→7F0 in glass and glass ceramics were investi-gated to analyze the local environment around Eu3+. Judd-Ofelt parameters were also calculated from emission spectra, which indicated that the Eu3+ ions entered the precipitated CaF2, SrF2, and BaF2 nanocrystallites. Heat treating could not pledge Eu3+ ions to coordinate with F in the precipitated MgF2 nanocrystallites, owing to the smaller radius of Mg2+ than that of Eu3+. 相似文献
440.
By heat treating the alkaline earth fluorosilicate glass, transparent glass ceramics containing alkaline earth fluoride nanocrystallites were prepared. The luminescence spectra and phonon sideband associated with the Eu^3+:^5D2→^7F0 in glass and glass ceramics were investigated to analyze the local environment around Eu^3+. Judd-Ofelt parameters were also calculated from emission spectra, which indicated that the Eu^3+ ions entered the precipitated CaF2, SrF2, and BaF2 nanocrystallites. Heat treating could not pledge Eu^3+ ions to coordinate with F^- in the precipitated MgF2 nanocrystallites, owing to the smaller radius of Mg^2+ than that of Eu^3+. 相似文献