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1.
ABSTRACTThe reaction of formic acid (HCOOH) with chlorine atom and amidogen radical (NH 2) have been investigated using high level theoretical methods such BH&HLYP, MP2, QCISD, and CCSD(T) with the 6–311?+?G(2df,2p), aug-cc-pVTZ, aug-cc-pVQZ and extrapolation to CBS basis sets. The abstraction of the acidic and formyl hydrogen atoms of the acid by the two radicals has been considered, and the different reactions proceed either by a proton coupled electron transfer ( pcet) and hydrogen atom transfer ( hat) mechanisms. Our calculated rate constant at 298?K for the reaction with Cl is 1.14?×?10 ?13?cm 3?molecule ?1?s ?1 in good agreement with the experimental value 1.8?±?0.12/2.0?×?10 ?13?cm 3?molecule ?1?s ?1 and the reaction proceeds exclusively by abstraction of the formyl hydrogen atom, via hat mechanism, producing HOCO+ClH. The calculated rate constant, at 298?K, for the reaction with NH 2 is 1.71?×?10 ?15?cm 3?molecule ?1?s ?1, and the reaction goes through the abstraction of the acidic hydrogen atom, via a pcet mechanism, leading to the formation of HCOO+NH 3. 相似文献
2.
The bay-capping mechanism on PAH armchair edges and the kinetics of acetylene addition to 6–6–5 and 5–6–5 bays have been explored by ab initio/RRKM-ME calculations. The bays on the edges were modeled by C 21H 11 and C 20H 9 radicals produced by H abstractions from 7 H-benzo[ c]cyclopenta[ e]pyrene and dicyclopenta[ cf]pyrene. The C 20H 9 + C 2H 2 reaction is shown to have a low entrance barrier and to rapidly form the capped product, indaceno[2,1,8,7- cdefg]pyrene, along with ethynyl substituted dicyclopenta[ cf]pyrene at temperatures above 1400 K. The reactivity of C 21H 11 is shown to be governed by the location of the unpaired electron; the π radical R1 formed by H abstraction from the CH 2 group in 7 H-benzo[ c]cyclopenta[ e]pyrene reacts with C 2H 2 very slowly owing to a high entrance barrier, with the bay-capping rate constant approaching 10 −16 cm 3 molecule −1 s −1 only at temperatures above 2000 K. This result reaffirms that the growth of π aryl radicals via acetylene addition is inefficient and reflects the generally low reactivity of such radicals where the spin density is highly delocalized over the entire polyaromatic system. Alternatively, the σ C 21H 11 radical R2 produced by H abstraction from the five-membered ring at the bay rapidly reacts with C 2H 2 forming the bay-capped product, with the rate constant on the order of 10 −12 cm 3 molecule −1 s −1 at T ≥ 1500 K. Rate constants for the capping reactions at the 6–6–5 and 5–6–5 bays are compared with those at the 6–0–6, 6–6–6, and 6–5–6 bays. The site-specific bay-capping rate constants have been utilized in kMC simulations of the PAH growth and the results showed measurable differences when the 6–6–5 and 5–6–5 bay-capping reactions are taken into account, including an increase of the growth rate and the formation of closed-shell PAH and a rise of the number of embedded five-membered rings accompanied with a slight decrease of their overall amount. 相似文献
3.
Single-pulse shock-tube experiments were used to study the thermal decomposition of selected oxygenated hydrocarbons: Ethyl propanoate (C 2H 5OC(O)C 2H 5; EP), propyl propanoate (C 3H 7OC(O)C 2H 5; PP), isopropyl acetate ((CH 3) 2HCOC(O)CH 3; IPA), and methyl isopropyl carbonate ((CH 3) 2HCOC(O)OCH 3; MIC) The consumption of reactants and the formation of stable products such as C 2H 4 and C 3H 6 were measured with gas chromatography/mass spectrometry (GC/MS). Depending on the considered reactant, the temperatures range from 716–1102 K at pressures between 1.5 and 2.0 bar. Rate-coefficient data were obtained from first-order analysis. All reactants primarily decompose by six-center eliminations: EP → C 2H 4 + C 2H 5COOH (propionic acid); PP → C 3H 6 + C 2H 5COOH; IPA → C 3H 6 + CH 3COOH (acetic acid); MIC → C 3H 6 + CH 3OC(O)OH (methoxy formic acid). Experimental rate-coefficient data can be well represented by the following Arrhenius expressions: k(EP → products) = 10 13.49±0.16 exp(−214.95±3.25 kJ/mol/ RT) s −1; k(PP → products) = 10 12.21±0.16 exp(–191.21±2.79 kJ/mol/ RT) s −1; k(IPA → products) = 10 13.10±0.31 exp(–186.38±5.10 kJ/mol/ RT) s −1; k(MIC → products) = 10 12.43±0.29 exp(–165.25±4.46 kJ/mol/ RT) s −1. The determination of rate coefficients was based on the amount of C 2H 4 or C 3H 6 formed. The potential energy surface (PES) of the thermal decomposition of these four reactants was determined with the G4 composite method. A master-equation analysis was conducted based on energies and molecular properties from the G4 computations. The results indicate that the length of a linear alkyl substituent does not significantly influence the rate of six-center eliminations, whereas the change from a linear to a branched alkyl substituent results in a significant reactivity increase. The comparison between rate-coefficient data also shows that alkyl carbonates have higher reactivity towards decomposition by six-center elimination than esters. The results are discussed in in the context of reactivity patterns of carbonyl compounds. 相似文献
4.
3 MeV electron irradiation induced-defects in CuInSe 2 (CIS) thin films have been investigated. Both of the carrier concentration and Hall mobility were decreased as the electron fluence exceeded 1×10 17 cm −2. The carrier removal rate was estimated to be about 1 cm −1. To evaluate electron irradiation-induced defect, the electrical properties of CIS thin films before and after irradiation were investigated between 80 and 300 K. From the temperature dependence of the carrier concentration in non-irradiated thin films, we obtained ND=1.8×10 17 cm −3, NA=1.7×10 16 cm −3 and ED=18 meV from the SALS fitting to the experimental data on the basis of the charge balance equation. After irradiation, a new defect level was formed, and NT0=1.4×10 17 cm −3 and ET=54 meV were also obtained from the same procedure. From the temperature dependence of Hall mobility, the ionized impurity density was discussed before and after the irradiation. 相似文献
5.
The interaction between ammonia (NH 3) and nitric oxide (NO) at high temperatures is studied in this work using a shock tube combined with laser absorption diagnostics. The system simultaneously measured the NH 3 and NO time-histories during the reaction processes of the shock-heated NH 3/NO/CO/Ar mixtures (NH 3:NO ≈ 0.9:1.0 and 1.4:1.0). The absorption cross-sections of NH 3 near 1122.10 cm –1 and NO at 1900.52 cm –1 (characterized in this study) were used for measuring NH 3 and NO time-histories with the temperature measured by two CO absorption lines. The measured NH 3 and NO time-histories at 1614–1968 K and 2.4–2.8 atm were compared with predictions of seven recent kinetics models. The predictions that based on different mechanisms are very different and the measured profiles are within the range of the predictions. The Glarborg, NUI Galway Syngas-NO x, and Mathieu mechanisms give the closest predictions to the measurements. Kinetics analyses indicate that the NH 3 and NO consumption rates are extremely sensitive to the rate constants and branching ratio of NH 2 + NO = N 2 + H 2O and NH 2 + NO = NNH + OH, which are more reliably represented in the Glarborg and NUI Galway Syngas-NO x mechanisms. The performances of Glarborg mechanisms at lower initial temperatures can be apparently improved by revising the rate constants and branching ratio of NH 2 + NO = N 2 + H 2O and NH 2 + NO = NNH + OH. These two reactions are also the primary pathways for NO reduction and NH 3 is mainly consumed via NH 3 + OH = NH 2 + H 2O and NH 3 + H = NH 2 + H 2. Trace amounts of NO 2 and N 2O impurities decompose to form O radical followed by the generation of OH radical via H-abstraction reactions, which significantly affects the predictions of NH 3 and NO according to kinetics analyses. 相似文献
6.
Rate constants for proton-transfer reactions of the type XH + + CH 3NO 2 → CH 3NO 2H + + X (1) where X = H 2, D 2, N 2, CO 2, CH 4, N 2O, CO, H 2O, HCN, CH 3CHCH 2, and CH 3OH, and of the type CH 3NO 2 + X − → XH + CH 2NO 2− (2) where X = NH 2, H, D, OH, CH 3O, C 2H 5O, C 2H, CH 3COCH 2, and CH 3S have been measured at 297 ± 2 K using the flowing afterglow technique with values ranging from 0.1 to 1.3 × 10 −8 cm 3 molecule −1 s −1. Rate constant and equilibrium ion concentration measurements for proton transfer from C 3H 7+ to CH 3NO 2, from CH 3NO 2H + to CH 3OH, and from CH 3NO 2 to CH 3S − provided values for equilibrium constants of 3 ± 1, 1.3 ± 0.4 and 1.9 ± 0.3, respectively, from which values for PA298(CH 3NO 2) = PA298(CH 3OH) = 181 ± 3 kcal mol −1 and PA298(CH 2NO 2−) = 357.6 ± 2.8 kcal mol −1 were deduced. Several of the more exothermic members of reactions of type (1) appeared to proceed, at least in part, by dissociative proton transfer to produce NO + and CH 3NO +. In the case of reactions of type (2), proton transfer predominated over exothermic NO 2− displacement. The measured rate constants are compared with the predictions of the Langevin, average-dipole-orientation and locked-dipole theories of ion-molecule collisions. The average-dipole-orientation theory provides the most realistic collision rates for these reactions although these appear to be underestimated on average by ca. 10% and ca. 5% for reactions of type (1) and (2), respectively. The observed variations of reaction efficiency with exothermicity are discussed in terms of current models of the mechanism for proton transfer. 相似文献
7.
The current–voltage ( I– V) characteristics of Al/SnO 2/p-Si (MIS) Schottky diodes prepared by means of spray deposition method have been measured at 80, 295 and 350 K. In order to interpret the experimentally observed non-ideal Al/SnO 2/p-Si Schottky diode parameters such as, the series resistance Rs, barrier height ΦB and ideality factor n, a novel calculation method has been reported by taking into account the applied voltage drop across interfacial oxide layer Vi and ideality factor n in the current transport mechanism. The values obtained for Vi were subtracted from the applied voltage values V and then the values of Rs were recalculated. The parameters obtained by accounting for the voltage drop Vi have been compared with those obtained without considering the above voltage drop. It is shown that the values of Rs estimated from Cheung’s method were strongly temperature-dependent and decreased with increasing temperature. It is shown that the voltage drop across the interfacial layer will increase the ideality factor and the voltage dependence of the I– V characteristics. The interface state density Nss of the diodes has an exponential growth with bias towards the top of the valance band for each temperature; for example, from 2.37 × 10 13 eV −1 cm −2 in 0.70− Ev eV to 7.47 × 10 13 eV −1 cm −2 in 0.62− Ev eV for 295 K. The mean Nss estimated from the I– V measurements decreased with increasing the temperature from 8.29 × 10 13 to 2.20 × 10 13 eV −1 cm −2. 相似文献
8.
The temporal variation of chemiluminescence emission from OH ?(A 2 Σ +) and CH ?(A 2 Δ) in reacting Ar-diluted H 2/O 2/CH 4, C 2H 2/O 2 and C 2H 2/N 2O mixtures was studied in a shock tube for a wide temperature range at atmospheric pressures and various equivalence ratios. Time-resolved emission measurements were used to evaluate the relative importance of different reaction pathways. The main formation channel for OH ? in hydrocarbon combustion was studied with CH 4 as benchmark fuel. Three reaction pathways leading to CH ? were studied with C 2H 2 as fuel. Based on well-validated ground-state chemistry models from literature, sub-mechanisms for OH ? and CH ? were developed. For the main OH ?-forming reaction CH+O 2=OH ?+CO, a rate coefficient of k 2=(8.0±2.6)×10 10 cm 3?mol ?1?s ?1 was determined. For CH ? formation, best agreement was achieved when incorporating reactions C 2+OH=CH ?+CO ( k 5=2.0×10 14 cm 3?mol ?1?s ?1) and C 2H+O=CH ?+CO ( k 6=3.6×10 12exp(?10.9 kJ?mol ?1/ RT) cm 3?mol ?1?s ?1) and neglecting the C 2H+O 2=CH ?+CO 2 reaction. 相似文献
9.
A proton-conducting polymer electrolyte based on agar and ammonium nitrate (NH4NO3) has been prepared through solution casting technique. The prepared polymer electrolytes were characterized by impedance spectroscopy, X-ray diffraction, and Fourier transform infra-red spectroscopy. Impedance analysis shows that sample with 60 wt.% NH4NO3 has the highest ionic conductivity of 6.57 × 10−4 S cm−1 at room temperature. As a function of temperature, the ionic conductivity exhibits an Arrhenius behaviour increasing from 6.57 × 10−4 S cm−1 at room temperature to 1.09 × 10−3 S cm−1 at 70 °C. Transport parameters of the samples were calculated using Wagner’s polarization method and thus shows that the increase in conductivity is due to the increase in the number of mobile ions. Fuel cell has been constructed with the highest proton conductivity polymer 40agar/60NH4NO3 and the open circuit voltage is found to be 558 mV. 相似文献
10.
Hydrogen peroxide (H 2O 2) and hydroperoxy (HO 2) reactions present in the H 2O 2 thermal decomposition system are important in combustion kinetics. H 2O 2 thermal decomposition has been studied behind reflected shock waves using H 2O and OH diagnostics in previous studies (Hong et al. (2009) [9] and Hong et al. (2010) [6,8]) to determine the rate constants of two major reactions: H 2O 2 + M → 2OH + M ( k1) and OH + H 2O 2 → H 2O + HO 2 ( k2). With the addition of a third diagnostic for HO 2 at 227 nm, the H 2O 2 thermal decomposition system can be comprehensively characterized for the first time. Specifically, the rate constants of two remaining major reactions in the system, OH + HO 2 → H 2O + O 2 ( k3) and HO 2 + HO 2 → H 2O 2 + O 2 ( k4) can be determined with high-fidelity.No strong temperature dependency was found between 1072 and 1283 K for the rate constant of OH + HO 2 → H 2O + O 2, which can be expressed by the combination of two Arrhenius forms: k3 = 7.0 × 10 12 exp(550/ T) + 4.5 × 10 14 exp(?5500/ T) [cm 3 mol ?1 s ?1]. The rate constants of reaction HO 2 + HO 2 → H 2O 2 + O 2 determined agree very well with those reported by Kappel et al. (2002) [5]; the recommendation therefore remains unchanged: k4 = 1.0 × 10 14 exp(?5556/ T) + 1.9 × 10 11+exp(709/ T) [cm 3 mol ?1 s ?1]. All the tests were performed near 1.7 atm. 相似文献
11.
Oxygen tracer diffusion coefficient ( D⁎) and surface exchange coefficient ( k⁎) have been measured for (La 0.75Sr 0.25) 0.95Cr 0.5Mn 0.5O 3−δ using isotopic exchange and depth profiling by secondary ion mass spectrometry technique as a function of temperature (700–1000 °C) in dry oxygen and in a water vapour-forming gas mixture. The typical values of D⁎ under oxidising and reducing conditions at ∼ 1000 °C are 4 × 10 − 10 cm 2 s − 1 and 3 × 10 − 8 cm 2 s − 1 respectively, whereas the values of k⁎ under oxidising and reducing conditions at ∼ 1000 °C are 5 × 10 − 8 cm s − 1 and 4 × 10 − 8 cm s − 1 respectively. The apparent activation energies for D⁎ in oxidising and reducing conditions are 0.8 eV and 1.9 eV respectively. 相似文献
12.
Third-order rate coefficients have been determined at 295 K for the formation of dimeric parent cations in benzene, benzene-d 6, toluene, the xylenes, mesitylene, and fluoro- and chlorobenzene using the NBS high pressure photoionization mass spectrometer. The reactions are all quite fast, the rate coefficients falling in the range 0.5–6 · 10 −25 cm 6 molecule −2 s −1. The differences in rates observed are rationalized in terms of structural (geometric) considerations, and upper limits are established for the binding energies in (C 6H 6) 2+ and (C 6H 5CH 3) 2+. The temperature dependence for production of (C 6D 6) 2+ has been determined from 227 to 316 K, and the rate coefficient seems to obey a simple 1/ T relationship over this range. The detection of trimeric species in benzene is also reported for the first time. Additional experiments involving benzene-nitric oxide mixtures are also reported, which include detection of an apparent equilibrium of the type NO + + C 6H 6 ⇆ C 6H 6+ + NO. 相似文献
13.
The title compound C 6H 5CH 2C 5H 4NH +·HSeO 4− crystallizes in the orthorhombic system with the space group Pbca and the following unit cell dimensions: a=27.449(5) Å; b=10.821(6) Å and c=8.830(1) Å.The structure consists of infinite parallel two-dimensional planes built of HSeO 4− anions and C 6H 5CH 2C 5H 4NH + cations mutually.Differential scanning calorimetry study on 4-benzylpyridinium monohydrogen-selenate was carried out. A high temperature second order phase transition at 363 K was found and characterized by electric measurements. The Raman of polycrystalline sample has been recorded at different temperature between 297 and 373 K.The conductivity relaxation parameters associated with some H + conduction have been determined from an analysis of the M′′/M′′ max spectrum measured in a wide temperature range. An appearance of the superionic phase transition in 4-BSe is closely related to a liberation or even a rotation increase of HSeO 4− groups with heating. 相似文献
14.
Proton dynamics in (NH 4) 3H(SO 4) 2 has been studied by means of 1H solid-state NMR. The 1H magic-angle-spinning (MAS) NMR spectra were traced at room temperature (RT) and at Larmor frequency of 400.13 MHz. 1H static NMR spectra were measured at 200.13 MHz in the range of 135–490 K. 1H spin-lattice relaxation times, T1, were measured at 200.13 and 19.65 MHz in the ranges of 135–490 and 153–456 K, respectively. The 1H chemical shift for the acidic proton (14.7 ppm) indicates strong hydrogen bonds. In phase III, NH 4+ reorientation takes place; one type of NH 4+ ions reorients with an activation energy ( Ea) of 14 kJ mol − 1 and the inverse of a frequency factor ( τ0) of 0.85 × 10 − 14 s. In phase II, a very fast local and anisotropic motion of the acidic protons takes place. NH 4+ ions start to diffuse translationally, and no proton exchange is observed between NH 4+ ions and the acidic protons. In phase I, both NH 4+ ions and the acidic protons diffuse translationally. The acidic protons diffuse with parameters of Ea = 27 kJ mol − 1 and τ0 = 4.2 × 10 − 13 s. The translational diffusion of the acidic protons is responsible for the macroscopic proton conductivity, as the NH 4+ translational diffusion is slow and proton exchange between NH 4+ ions and the acidic protons is negligible. 相似文献
15.
Field evaporation of silver and field desorption of silver surface compounds were investigated by analysing positive ions with a mass spectrometer. In particular, the well known adsorption states of oxygen, and further the interactions of H 2O, NH 3, H 2, CO and CH 4 were measured in the field ion mass spectrometer under steady state fields of > 0.1 V/Å with a sensitivity of < 0.1 ions s ?1 and at temperatures between 80 °K and 425 °K. Although oxygen is usually chemisorbed at Ag surfaces, no AgO +, AgO +2 or other Ag-O compounds could be detected as positive ions, Ag + and O 2+ are the only observed ions at best image fields in oxygen up to fields of field evaporation of Ag +(≈ 2.2 V/Å). Even after the actual adsorption of oxygen with zero-field (6 × 10 5 Langmuir at 10 ?3 Torr) at 323 °K and 473 °K and subsequent application of the desorption field at 210°K no silver-oxygen compounds were found in positive ionic form. Small quantities of AgO + and AgO +2 were only formed — besides Ag(H 2O) x+ complexes — if atomic oxygen was supplied by the field induced dissociation of water.Gases which do not adsorb on silver under zero-field conditions (H 2, CO, CH 4, N 2) yield the ions Ag(H 2) n, Ag(CO) n+, n=1, 2; AgCH 4+, AgN 2+. The situation with H 2O and NH 3 is more complicated: Molecular ions [Ag(H 2O) n] +· mH 2O, n=1,…, 4, m=1,…, 8 and [Ag(NH 3) n] +· mNH 3, n=1, 2, m=1,…, 6 are found besides Ag +.From the temperature and field dependence conclusions are drawn about the mechanisms of evaporation and formation of ionic surface complexes. The activation energies of evaporation of Ag + are found to depend on the square root of the field strength. In general, the generation of surface compounds can be described by field induced reactions rather than usual gas adsorption. 相似文献
16.
This research studied the effects of combined ultrasound and 3% sodium alginate (SA) coating pretreatment (US + Coat) on mass transfer kinetics, quality aspects, and cell structure of osmotic dehydrated (OD) pumpkin. The results of the pretreatment were compared with the results of control (non-pretreated osmotic dehydration) and other three pretreatment methods, which were 1) ultrasound in distilled water for 10 min (USC), 2) ultrasound in 70% (w/w) sucrose solution (US) for 10, 20 and 30 min, and 3) coating with 1%, 2%, 3% (w/w) SA. The coating pretreatments with SA resulted in a higher water loss (WL) but lower water activity and solid gain (SG) than other treatments. US pretreatments resulted in the highest effective diffusion coefficients of water ( Dw) and solid ( Ds) but the cell structure of the product was deformed. The 3% SA coating treatment had the highest WL/SG (5.28) but with the longest OD time (12 h). Using the US + Coat pretreatment gave satisfactory high WL/SG (5.18), Dw (1.09 × 10 −10 m 2s −1) and Ds (5.15 × 10 −11 m 2s −1), reduced the OD time to 9 h, and preserved the cell structure of the product. This research suggests that US + Coat pretreatment can be an effective processing step in the production of OD pumpkin. 相似文献
17.
Results of the first μSR studies using Merck FO Optipur silica powder, which contains paramagnetic impurities at the ppb level
and has a surface area of 610±20 m 2/g. are reported. Above 20 K, the transverse field muonium relaxation rate is roughly constant at 0.5 μs −1. Upon the addition of oxygen at ppm levels, the relaxation rate increases linearly with O 2 concentration in the temperature range from 40–100 K yielding two-dimensional depolarization rate constants on the order
of 10 −4 cm 2 molecule −1 s −1. As the temperature is increased further, both oxygen and muonium desorb from the surface yielding a three-dimensional rate
constants at 300 K of 3.1(3)×10–10 −10 cm 3 molecule −1 s −1, in agreement with the gas phase value. Longitudinal field measurements suggest that MuO 2 is formed and is able to spin exchange with other oxygen molecules. 相似文献
18.
Kinetics and mechanisms for reactions of OH with methanol and ethanol have been investigated at the CCSD(T)/6-311 + G( 3df, 2p)//MP2/6-311 + G( 3df, 2p) level of theory. The total and individual rate constants, and product branching ratios for the reactions have been computed in the temperature range 200-3000 K with variational transition state theory by including the effects of multiple reflections above the wells of their pre-reaction complexes, quantum-mechanical tunneling and hindered internal rotations. The predicted results can be represented by the expressions k1 = 4.65 × 10 −20 × T2.68 exp(414/ T) and k2 = 9.11 × 10 −20 × T2.58 exp(748/ T) cm 3 molecule −1 s −1 for the CH 3OH and C 2H 5OH reactions, respectively. These results are in reasonable agreements with available experimental data except that of OH + C 2H 5OH in the high temperature range. The former reaction produces 96-89% of the H 2O + CH 2OH products, whereas the latter process produces 98-70% of H 2O + CH 3CHOH and 2-21% of the H 2O + CH 2CH 2OH products in the temperature range computed (200-3000 K). 相似文献
19.
A simple method for synthesis of gold nanoparticles (AuNPs) using Aspergillum sp. WL-Au was presented in this study. According to UV–vis spectra and transmission electron microscopy images, the shape and size of AuNPs were affected by different parameters, including buffer solution, pH, biomass and HAuCl 4 concentrations. Phosphate sodium buffer was more suitable for extracellular synthesis of AuNPs, and the optimal conditions for AuNPs synthesis were pH 7.0, biomass 100 mg/mL and HAuCl 4 3 mM, leading to the production of spherical and pseudo-spherical nanoparticles. The biosynthesized AuNPs possessed excellent catalytic activities for the reduction of 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, o-nitroaniline and m-nitroaniline in the presence of NaBH 4, and the catalytic rate constants were calculated to be 6.3×10 −3 s −1, 5.5×10 −3 s −1, 10.6×10 −3 s −1, 8.4×10 −3 s −1 and 13.8×10 −3 s −1, respectively. The AuNPs were also able to catalyze the decolorization of various azo dyes (e.g. Cationic Red X-GRL, Acid Orange II and Acid scarlet GR) using NaBH 4 as the reductant, and the decolorization rates reached 91.0–96.4% within 7 min. The present study should provide a potential candidate for green synthesis of AuNPs, which could serve as efficient catalysts for aromatic pollutants degradation. 相似文献
20.
NH 4PO 3/SiO 2 composite based electrolyte with SiO 2 as supporting matrix was prepared. A thermogravimetric analysis was performed. Its electrochemical properties were investigated by an impedance spectroscopy within the temperature range of 100–300 °C under dry and humid atmospheres. The maximum conductivity is 6 mS cm − 1 at 300 °C under dry N 2 and 0.1 S cm − 1 at 200 °C under humid N 2. 相似文献
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