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41.
《分离科学与技术》2012,47(13):1926-1936
Hydrodesulfurization-treated (HDS-treated) gasoline with low sulfur content is an important source of primary fuel for fuel cells, although it contains sulfur compounds, thiophene (TP), benzothiophene (BTP), and thiophene alkylated derivatives, known as a poison for the reformer catalysts and the electrode catalysts of fuel cells. Adsorptive removal of TP from model organic liquid of HDS-treated gasoline was screened on different kinds of inorganic adsorbents: hydrous metal oxides, mixed metal oxides, aluminosilicates, acidic salts of multivalent metal, hetero polyacidic salt, and metal salts of iron hexacyanate. All the adsorbents showed very low TP uptake, less than 5% of the total TP amount when metal ions were not loaded on the adsorbent. On the other hand, some metal ion (Ag, Cu, and Ce) loaded adsorbents had good TP adsorptive properties. On simple metal oxides, Ag ion was better for the formation of adsorption center than Ce or Ni ions. In zeolite group, Ce-loaded Y-zeolite showed the largest TP uptake (99% of the total TP amount). Hydrous cerium oxide and the Ce-loaded adsorbents prepared from K4[Fe(CN)6], Silicagel, TiO2, and ZrO2 did not show TP selectivity. The effect of coexisting toluene on TP adsorption was studied from the TP solutions with and without toluene. 相似文献
42.
Carlos Romero‐Nieto Stefan Durben Ila M. Kormos Thomas Baumgartner 《Advanced functional materials》2009,19(22):3625-3631
This paper describes a structure–property study using two dithieno[3,2‐b;2′,3′‐d]phosphole building blocks for the generation of white light emission and the incorporation of these units in a single polystyrene material. The emission of one of the light‐emitting organophosphorus building blocks can efficiently be switched from orange to green by simple protonation of the amino functional groups that are part of the π‐conjugated scaffold. The resulting three components (blue, green, and orange) exhibit photophysical properties that allow for an efficient fluorescence resonance energy transfer (FRET) in the mixture/polymer and provide intense white fluorescence upon excitation of the blue component; the fluorescence is close to pure white in solution and similar to the emission of an incandescent light bulb in the thin film. The results nicely illustrate the intriguing features that can be obtained by exclusively using organophosphorus‐based organic electronic materials. 相似文献
43.
The synthesis of a novel thiophene isoster of aceanthrylene is reported. The sequence involves, a newly observed regiospecific condensation of oxalylchloride to naphtho[2,3-b]thiophene. Reduction of the quinone and dehydrogenation gave the title compound in 28% overall yield. The proton nmr signals of the title compounds were assigned on the basis of COSY and NOE difference spectroscopy. Its isolectronic nature with aceanthrylene is seen in the similarity of the UV spectra. 相似文献
44.
新型噻吩脱硫剂的研究 总被引:4,自引:1,他引:3
利用以活性炭作载体的脱硫剂脱除混合气中的噻吩,该脱硫剂可再生使用。对硫容、放硫现象、再生方法进行了讨论。 相似文献
45.
Emir E. Escalona Pedro R. Pereira-Almao Jimmy Castillo Jeannette Hung Carmelo Bolívar Carlos E. Scott 《Catalysis Letters》2006,112(3-4):227-230
NiMo and FeMo nanometric particles were prepared by thermal decomposition of water in oil emulsions, where the aqueous phase
was a solution of iron or nickel heteropolymolybdates. Decomposition experiments were carried out at 573 K and 70 Bar of hydrogen,
with carbon disulfide added to the emulsions. Solids were characterized by X ray diffraction, confocal microscopy and BET
surface area. Thiophene hydrodesulfurization was performed in a continuous flow microreactor at 553 K and 1.0 Bar. Particles
with diameters between 370 and 560 nm were obtained, and thiophene HDS was in the order NiMoS > MoS ≈ FeMoS > NiS > FeS. The
feasibility of using thermal decomposition of emulsions to obtain nanometric bimetallic sulfides particles was shown. 相似文献
46.
47.
Congbin Fan Ping Yang Xiaomei Wang Gang Liu Xiaoxia JiangHongzheng Chen Xutang TaoMang Wang Minghua Jiang 《Solar Energy Materials & Solar Cells》2011,95(3):992-1000
A series of new “D-A-D” chromophores containing hexafluorocyclopentene thiophene as an acceptor and a triphenylamine unit as a donor, called TP-G1, TP-G2, TPB-G1 and TPB-G2, were designed and synthesized. Heterojunction organic photovoltaic (OPV) cells containing these chromophores were fabricated, and device 1, with the structure of ITO/PEDOT:PSS/TP-G1:P3HT/LiF/Al, displayed an open-circuit voltage (Voc), short-circuit current (Jsc) and power-conversion efficiency (η) of 0.74 V, 1.178 mA/cm2 and 0.22%, respectively. The triphenylamine group could effectively induce the open-ring isomer to close because the 4- and 4′- positions of the benzene rings were substituted by an electron-donating group and the value of the quantum yields of the closed-ring isomers increased. As a result, the closed-ring isomer facilitated intramolecular π-electron delocalization and exhibited a broad absorption band ranging from 200 to 850 nm. Due to the fluorine substitution of hexafluorocylopentene at the molecular center and the hole-transport characteristics of the triphenylamine moiety on the periphery, our chromophores showed obvious dual semiconductor properties, i.e., n- and p-type, which demonstrated a potential application for OPV devices. 相似文献
48.
49.
B. J. R. Philogène J. T. Arnason C. W. Berg F. Duval P. Morand 《Journal of chemical ecology》1986,12(4):893-898
The botanical phototoxin, -terthienyl (-T) was spray applied to natural or artificial pools containing mosquito (Aedes intrudens) larvae and nontarget invertebrates (caddisfly, damselfly, midge, shrimp,Daphnia, snail) and one vertebrate (trout) at concentrations varying from 0.01 to 1 kg/hectare, under field and laboratory conditions. All field-treated nontarget invertebrates survived -T treatment better thanA. intrudens which can be controlled at doses as low as 0.01 kg/hectare within one week. Under laboratory conditions, snails and trout survived -T and UV treatments up to 10 kg/ hectare. These results compare favorably with organophosphates and pyrethroid insecticides currently used for mosquito control. The results confirm that -T is a highly effective larvicide with acceptable nontarget effects. 相似文献
50.
首次从2,3-二甲氧基-1,3-丁二烯衍生物出发,微波辐射下采用一锅法成功合成了一系列3,4-乙撑二氧噻吩类化合物.实验表明,该法具有反应条件温和、收率高和操作简单的优点.3,4-乙撑二氧噻吩类化合物的结构经 ~1HNMR 、~13CNMR、IR和元素分析进行了表征.也讨论了原料的量、催化剂和溶剂对3,4-乙撑二氧噻吩(EDOT)收率的影响. 相似文献