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61.
Electrochromic window based on polyaniline 总被引:1,自引:0,他引:1
A portable electrochromic display window (7 cm × 5 cm) has been constructed using a polyaniline-coated SnO2 glass plate and an AlCl3(aq) melt. The window colour can be switched from dark green to yellow or colourless by applying a small voltage of −0.5 to 2.5
V. It exhibits a fast response time (ms) and a long cycle life (1000).
Received: 27 May 1997 / Accepted: 8 September 1997 相似文献
62.
Summary Controlled-potential coulometric estimations of phenyl thiourea, thioglycollic acid and cysteine have been carried out employing 1 N hydrochloric acid, Clark and Lubs buffer and phosphate buffer pH 6.2 as electrolytes, respectively. Quantities ranging from 11–34 mg, 5–20 mg and 5–20 mg have been estimated with average errors of ± 0.55 mg, ± 0.30 mg and ± 0.38 mg, respectively. The elimination of a background in the case of phenyl thiourea has been achieved by carrying out the oxidation at low temperature.
Zusammenfassung Eine coulometrische Bestimmung von Phenylthioharnstoff, Thioglykolsäure und Cystein wurde bei kontrolliertem Potential unter Verwendung von 1 N Salzsäure, Puffer nach Clark und Lubs bzw. Phosphatpuffer pH 6,2 als Elektrolyten durchgeführt. Bei Probeeinwaagen von 11–34 mg, 5–20 mg bzw. 5–20 mg wurden mittlere Fehler von ± 0,55 mg, ± 0,30 mg bzw. ± 0,38 mg erhalten. Ein Untergrundstrom, der bei Phenylthioharnstoff auftrat, wurde durch Arbeiten bei niedriger Temperatur eliminiert.相似文献
63.
Reaction of copper(I) iodide with pyrrole-2-carbaldehydethiosemicarbazone (Hptsc) in a 1:1 mole ratio in MeCN, followed by addition of one mole of Ph3P, yielded a complex of empirical formula, CuI(Hptsc)(Ph3P), whose X-ray structure determination has shown that it exists as an iodo-bridged dinuclear copper(I) complex, [Cu2(-I)2(
1-S-Hptsc)2(PPh3)2](1). The central kernel, Cu(-I)2Cu forms a parallelogram with unequal Cu—I distances {Cu—I, 2.644(2), 2.707(2)Å} and bond angles {Cu—I—Cu, 70.72(7), I—Cu—I, 109.28(7)°}. Each Cu atom is further bonded to one S atom of Hptsc and one P atom of Ph3P, thus completing tetracoordination. The Cu...Cu separation of 3.097(4)Å is close to the sum of the van der Waals radius of the Cu atom, 2.80 Å. Compound (1) involves relatively strong inter-dimer hydrogen bonding via hydrazinic and pyrrole ring hydrogens with sulfur and iodine atoms respectively of the adjacent dimer {N(1)H...S#2, 2.50 Å; N(4)H...I#3, 2.91 Å}. The complex represents the first report of a copper(I) dimer with a thiosemicarbazone. 相似文献
64.
Pattanayek R Sethaphong L Pan C Prhavc M Prakash TP Manoharan M Egli M 《Journal of the American Chemical Society》2004,126(46):15006-15007
Chemical modification of nucleic acids at the 2'-position of ribose has generated antisense oligonucleotides (AONs) with a range of desirable properties. Electron-withdrawing substituents such as 2'-O-[2-(methoxy)ethyl] (MOE) confer enhanced RNA affinity relative to that of DNA by conformationally preorganizing an AON for pairing with the RNA target and by improving backbone hydration. 2'-Substitution of the ribose has also been shown to increase nuclease resistance and cellular uptake via changes in lipophilicity. Interestingly, incorporation of either 2'-O-[2-(methylamino)-2-oxoethyl]- (NMA) or 2'-O-(N-methylcarbamate)-modified (NMC) residues into AONs has divergent effects on RNA affinity. Incorporation of 2'-O-NMA-T considerably improves RNA affinity while incorporation of 2'-O-NMC-T drastically reduces RNA affinity. Crystal structures at high resolution of A-form DNA duplexes containing either 2'-O-NMA-T or 2'-O-NMC-T shed light on the structural origins of the surprisingly large difference in stability given the relatively minor difference in chemistry between NMA and NMC. NMA substituents adopt an extended conformation and use either their carbonyl oxygen or amino nitrogen to trap water molecules between phosphate group and sugar. The conformational properties of NMA and the observed hydration patterns are reminiscent of those found in the structures of 2'-O-MOE-modified RNA. Conversely, the carbonyl oxygen of NMC and O2 of T are in close contact, providing evidence that an unfavorable electrostatic interaction and the absence of a stable water structure are the main reasons for the loss in thermodynamic stability as a result of incorporation of 2'-O-NMC-modified residues. 相似文献
65.
Electronic structures of 3 halopropenes have been investigated through semiempiricalscf-mo calculations using valence basis sets of atomic orbitals (ao) constructed from Slater type orbitals (sto). The electronic structures of stable conformers have been predicted and the corresponding calculated dipole moments show
good agreement with experimental data. The considerable differences between the dipole moments of various conformers confirm
the hindrance to internal rotation about the C−C bond, i.e., the existence of a definite potential barrier to rotation. The
barrier heights hindering the internal rotation in each system are also estimated. 相似文献
66.
Zixiang Liu Yuanzheng Zhu Jonathan R. Clausen Jeremy B. Lechman Rekha R. Rao Cyrus K. Aidun 《国际流体数值方法杂志》2019,91(5):i-i
A hybrid computational method coupling the lattice-Boltzmann (LB) method and a Langevin-dynamics (LD) method is developed to simulate nanoscale particle and polymer (NPP) suspensions in the presence of both thermal fluctuation and long-range many-body hydrodynamic interactions (HIs). Brownian motion of the NPP is explicitly captured by a stochastic forcing term in the LD method. The LD method is two-way coupled to the nonfluctuating LB fluid through a discrete LB forcing source distribution to capture the long-range HI. To ensure intrinsically linear scalability with respect to the number of particles, a Eulerian-host algorithm for short-distance particle neighbor search and interaction is developed and embedded to LB-LD framework. The validity and accuracy of the LB-LD approach are demonstrated through several sample problems. The simulation results show good agreements with theory and experiment. The LB-LD approach can be favorably incorporated into complex multiscale computational frameworks for efficiently simulating multiscale multicomponent particulate suspension systems such as complex blood suspensions. 相似文献
67.
An efficient protocol for the regioselective aza-Michael addition of amines with acrylates using CaL B as a biocatalyst at 60 °C has been developed. The reaction is applicable to a wide variety of primary and secondary amines with different acrylates to synthesize the corresponding β-amino esters with good yields. An alternative route for the synthesis of higher β-amino esters through the additional transesterification step is also studied and was found effective. 相似文献
68.
In this study, bacteria associated with marine organisms were screened for the production of exopolysaccharides(EPSs) on MY media containing sea salts(2.5%-10%). Three selected isolates were identified as Alteromonas sp. PRIM-21, Nitratireductor sp. PRIM-24 and Enterobacter sp. PRIM-26 using 16 S r RNA gene sequencing. Optimization of the growth and EPS production kinetics in relation to incubation time were assessed. The purified EPS yield was 590, 650 and 540 mg·L-1 culture media respectively in Alteromonas sp. PRIM-21, Nitratireductor sp. PRIM-24 and Enterobacter sp. PRIM-26. Biochemical and FTIR analyses revealed the presence of biologically important functional groups in the EPS produced by all the three isolates. The EPS produced by Nitratireductor sp. PRIM-24 and Alteromonas sp. PRIM-21 showed 2.0% sulfate content. These bacterial EPS also showed antioxidant and emulsifying activities and the EPS produced by Enterobacter sp.PRIM-26 showed significantly higher antioxidant activities in terms of superoxide(IC50 0.33 mg·mL -1) and DPPH(IC50 0.44 mg·mL -1) radical scavenging. It also showed higher emulsifying activities against selected hydrophobic substrates with EI24 values above 60%. From the results of the study, it can be concluded that the isolated bacteria produce EPS that can be investigated in detail for biotechnological applications. 相似文献
69.
Kumar Anil Rao Rekha 《Journal of inclusion phenomena and macrocyclic chemistry》2022,102(3-4):313-326
Journal of Inclusion Phenomena and Macrocyclic Chemistry - Reactive oxygen species triggered oxidative stress contributes to the pathogenesis of numerous ailments such as myocardial infraction,... 相似文献
70.