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排序方式: 共有115条查询结果,搜索用时 93 毫秒
91.
Muhammad Adib Abdillah Mahbub Celfi Gustine Adios Michael Xu Bagas Prakoso James M. LeBeau Afriyanti Sumboja 《化学:亚洲杂志》2021,16(17):2559-2567
Design and synthesis of low-cost and efficient bifunctional catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in Zn-air batteries are essential and challenging. We report a facile method to synthesize heterostructure carbon consisting of graphitic and amorphous carbon derived from the agricultural waste of red bean pods. The heterostructure carbon possesses a large surface area of 625.5 m2 g−1, showing ORR onset potential of 0.89 V vs. RHE and OER overpotential of 470 mV at 5 mA cm−2. Introducing hollow FeCo nanoparticles and nitrogen dopant improves the bifunctional catalytic activity of the carbon, delivering ORR onset potential of 0.93 V vs. RHE and OER overpotential of 360 mV. Electron energy-loss spectroscopy (EELS) O K-edge map suggests the presence of localized oxygen on the FeCo nanoparticles, suggesting the oxidation of the nanoparticles. Zn-air battery with these carbon-based catalysts exhibits a peak power density as high as 116.2 mW cm−2 and stable cycling performance over 210 discharge/charge cycles. This work contributes to the advancement of bifunctional oxygen electrocatalysts while converting agricultural waste into value-added material. 相似文献
92.
介绍了以铽(Tb)激活的高密度发光玻璃和光导纤维发光玻璃的特性。它应用在X射线实时成像系统中,可大大改善空间分辨能力。用它做的转换屏比一般晶粒状荧光物质做的厚得多,特别适合用于高能X射线实时成像系统 相似文献
93.
Issa Yavari Mehdi Adib Manzarbanoo Esnaashari 《Monatshefte für Chemie / Chemical Monthly》2001,132(12):1557-1561
Summary. The reactive 1:1 intermediate produced in the reaction between dialkyl acetylenedicarboxylates and triphenylphosphine was
trapped by ethyl 3-(1,2-dihydroquinoline-2-ylidene)-pyruvate to yield the isomeric dialkyl 3-ethoxy-4-oxo-5-(2-(1H)-quinolinylidene)-2-cyclopentene-1,2-dicarboxylates and trialkyl 4-(2-quinolyl)-1-cyclobutene-1,2,3-tricarboxylates in nearly
4:1 ratio.
Received April 3, 2001. Accepted (revised) May 22, 2001 相似文献
94.
Summary. Dialkyl 4H-pyrrolo[3,2,1-ij]quinoline-4,5-dicarboxylates are obtained in quantitative yields from the 1:1:1 addition reaction between triphenylphosphine,
dialkyl acetylenedicarboxylates, and indole-7-carboxaldehyde. 相似文献
95.
Issa Yavari Mehdi Adib Hamid R. Bijanzadeh Majid M. M. Sadegi Hossein Logmani-Khouzani Javad Safari 《Monatshefte für Chemie / Chemical Monthly》2002,133(8):1109-1113
Summary. A dynamic NMR effect is observed in the 13C NMR spectra of anhydrous quinophthalone (quinoline yellow) and its monohydrate in the vicinity of 47°C and 0°C, respectively,
and is attributed to a restricted rotation around the polarized carbon–carbon double bond. The free energy of activation for
this process in anhydrous quinophthalone and the monohydrate is 65±2 and 55±2 kJ · mol−1, respectively, in CDCl3.
Received September 25, 2001. Accepted (revised) November 14, 2001 相似文献
96.
A simple and efficient synthesis of 5-hydroxy-3,5-diaryl-1,5-dihydro-2H-pyrrol-2-ones is described. Heating a mixture of an isocyanide and a 1,3-diaryl-2-propen-1-one under solvent-free conditions produces the title compounds in good to excellent yields. 相似文献
97.
The reactive 1:1 intermediate produced in the reaction between isocyanides and dialkyl acetylenedicarboxylates was trapped by 2,4-dihydro-3H-pyrazol-3-ones to yield highly functionalized 7-oxo-1H,7H-pyrazolo[1,2-a]pyrazoles in fairly good yields. 相似文献
98.
Mehdi Adib Mohammad Mahdavi Farzad Malihi Hamid Reza Bijanzadeh 《Tetrahedron letters》2009,50(52):7246-3194
A novel synthesis of 5-(alkylamino)-4-aryl-3-isoxazolecarboxamides is described. Heating a mixture of an isocyanide and a nitrostyrene in water afforded the title compounds in excellent yields. 相似文献
99.
In this paper a multiple strained layer structure with multiple quantum wells as a piezoelectric transducer is proposed for
generating and detecting nano ultrasound waves with nanometer wavelength and tera hertz frequency. By inducing femtosecond
optical pulses at this strained structure, internal piezoelectric field is changed. As a result longitudinal acoustic phonon
oscillations can be treated as nano acoustic waves. It could be noticed in simulated cases that detection of nano ultrasound
waves can be used in non destructive testing and high accuracy measurements with this structure. It is also shown that the
MQW structure design how influences in generated nano acoustic waves. 相似文献
100.
Hassan Ali Zamani Mohammad Reza Ganjali Parviz Norouzi Mahdi Adib Mohammad Aceedy 《Analytical sciences》2006,22(7):943-948
A highly La(III) ion-selective PVC membrane sensor based on N'-(1-pyridin-2-ylmethylene)-2-furohydrazide (NPYFH) as an excellent sensing material was successfully developed. The electrode shows a good selectivity for La(III) ion with respect to most common cations including alkali, alkaline earth, transition and heavy metal ions. The proposed sensor exhibits a wide linear response with slope of 19.2 +/- 0.6 mV per decade over the concentration range of 1.0 x 10(-6) - 1.0 x 10(-1) M, and a detection limit of 7.0 x 10(-7) M of La(III) ions. The sensor response is independent of pH in the range of 3.5-10.0. The proposed electrode was applied as an indicator electrode in potentiometric titration of La(III) ion with EDTA. 相似文献