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91.
Nonlinear Dynamics - Analysis of electrostatic floating potential fluctuations associated with multiple anodic double layer revealed a complexity dynamic coexisting with chaotic behavior. These... 相似文献
92.
Dongamanti Ashok Aamate Vikas Kumar Devulapally Mohan Gandhi Gundu Srinivas Balabadra Saikrishna Manga Vijjulatha Yogeeswari Perumal Sriram Dharmarajan Balasubramanian Sridhar 《Molecular diversity》2017,21(4):999-1010
Molecular Diversity - On the basis of reported antimycobacterial property of chroman-4-one pharmacophore, a series of chemically modified bis-spirochromanones were synthesized starting from... 相似文献
93.
Kaloor S. Harikrishnan Nithiyanandan Krishnan Nilima Manoj Kumar Anusree Krishna Gowtham Raj Devanathan Perumal Jemshiya Kalathil Jithu Krishna Dr. Reji Varghese 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(56):14100-14107
Two major hurdles in NP-based catalysis are the aggregation of the NPs and their recycling. Immobilization of NPs onto a 2D support is the most promising strategy to overcome these difficulties. Herein, amphiphilicity-driven self-assembly of galactose-hexaphenylbenzene-based amphiphiles into galactose-decorated 2D nanosheet is reported. The extremely dense decoration of reducing sugar on the surface of the sheets is used for the in situ synthesis and immobilization of ultrafine catalytically active AgNPs by using Tollens’ reaction. The potential of the system as a catalyst for the reduction of various nitroaromatics is demonstrated. Enhanced catalytic activity is observed for the immobilized AgNPs when compared to the corresponding discrete AgNPs. Recovery of the catalytic system from the reaction mixture by ultrafiltration and its subsequent recycling for several cycles without dropping its activity is shown. This is the first report demonstrating the in situ synthesis and immobilization of ultrafine AgNPs onto a 2D nanosheet that exhibits excellent catalytic performance for the reduction of nitroaromatics. 相似文献
94.
A mixed potential type yttria-stabilized zirconia-based sensor using NiO sensing electrode and Pt reference electrode was fabricated, and its NO2 sensing characteristics were examined at various operating temperatures in the range of 700–950 °C. It was observed that the sensitivity to NO2 strongly depends on the operating temperature of the sensor; the sensitivity decreases with increasing operating temperature, while the response/recovery rates increase. To rationalize this temperature dependence of NO2 response, polarization curves and complex impedances of the sensor were measured in the base gas and in the sample gas (400 ppm NO2?+?base gas) at various operating temperatures. It turned out that the operating temperature had a strong influence on the rate of anodic reaction of oxygen; the increased rate of anodic reaction leads to lower NO2 sensitivity and quicker response/recovery at higher operating temperature. 相似文献
95.
Condensation of furfural with cycloalkanones and substituted acetophenones catalyzed by solid NaOH results in α, α1-bis (substituted furfurylidene) cycloalkanones and chalcones in high yield under microwave irradiation for a duration of 2 minutes. 相似文献
96.
Fischer D. Feuerstein B. Moshammer R. Crespo López-Urrutia J. R. Draganic I. Lörch H. Perumal A. N. Ullrich J. DuBois R. D. 《Hyperfine Interactions》2003,148(1-4):177-183
Hyperfine Interactions - We have performed drying-humectation cyclical processes (CEBELCOR) on eight A36 low carbon steel coupons in NaCl solutions containing 1×10?2 M and... 相似文献
97.
The thermal isomerizations of N-[α-(alkylthio)alkyl]- and N-[α-(arylthio)alkyl]benzotriazoles have been investigated under N2 atmospheres (i) in toluene, xylene, MeOH, or EtOH, in the presence of acid catalysts and (ii) in the absence of solvent. The sulfide isomerization rates depend on the number of H-atoms carried by the C-atom attached to the N-atom of the benzotriazole: tertiary (no hydrogen) > secondary (1 hydrogen) > primary (2 hydrogens). The results support an isomenzation mechanism involving a heterolytic N? C bond cleavage with formation of sulfonium/carbonium and benzotriazolate ions. 相似文献
98.
Lewis acidic ionic liquid is shown to be for the first time an excellent medium and efficient catalyst for the synthesis of quinolines at room temperature from o‐amino aromatic carbonyls and ketones containing active methylene group. 相似文献
99.
Herbert C. Brown Prabhakar K. Jadhav P.Thirumalai Perumal 《Tetrahedron letters》1984,25(45):5111-5114
Methallyldiisopinocampheylborane, on condensation with aldehydes, provides 2-methyl-1-alken-4-ols in ≥ 90% enantiomeric purities. 相似文献
100.