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61.
晶态氮化碳薄膜的低温合成 总被引:1,自引:0,他引:1
The synthesis of carbon nitride films at low temperature has been investigated using pulsed arc discharge from methanol solution with nitrogen atmosphere. Raman spectra and X-ray diffraction (XRD) analysis suggest that crystalline carbon nitride films may be prepared at low substrate temperature (220 ℃). At same time, the substrate temperature has a significantly effect on the nitrogen content and structure of the films. Increasing substrate temperature (300 ℃) would decrease the content of nitrogen in the films and result in a formation of carbon films. 相似文献
62.
锂离子电池负极合金CoSn和Cu-Sn的制备与表征 总被引:9,自引:0,他引:9
CoSn alloy and Cu-Sn samples were synthesized by H2-reduction following solid-state reaction between Co(Ⅱ), Cu(Ⅱ), Sn(Ⅳ) and NaOH at ambient temperature. The samples were characterized by XRD, SEM. The results showed that CoSn alloy (80~200nm) is globe-shaped, ultrafine hexagonal material, and Cu-Sn alloy powder consists of two phases, i.e. Cu6Sn5 and Cu3Sn. Cu-Sn powder has spherical morphology and the particle size is estimated to be 60~70nm. The electrochemical performances of CoSn alloy and Cu-Sn powder were studied using lithium-ions model cell Li/LiPF6 (EC+DMC)/CoSn (or Cu-Sn). It was demonstrated the reversible discharge capacities for 10 cycles keep above 280mAh·g-1 for nanophase Cu-Sn, and 60mAh·g-1 for CoSn alloy. Differ-ential capacity plots showed that the reaction mechanisms of Cu-Sn with lithium were reversible. 相似文献
63.
The gas–liquid gliding arc discharge plasma is used directly to study degradation and dechlorination of 4-Chlorophenol (4-CP)
in solution. The typical AC waveforms of discharge voltage and current revealed that the discharge behavior was not definitely
periodic. The chemical oxygen demand (COD) abatement of 4-CP solution with stainless steel electrode is higher than that with
aluminum or brass electrode; When air was used as carrier gas the COD abated from 1,679.2 to 190 mg/L (i.e., 88.68% abatement)
after 76 min plasma treatment; Increasing gas–liquid mixing rate could also increase the degradation of 4-CP; adding appropriate
amounts of Fe2+ or iron chips to the solution were found to be favorable for 4-CP degradation. The main intermediates of 4-CP degradation
are p-benzoquinone, hydroquinone, 4-chlorocatechol, p-chloronitrobenzene, and ring cleavage products (acetic acid, glycol,
propanone, and others). Furthermore, possible pathways of 4-CP degradation in solution are proposed. 相似文献
64.
65.
The analytical performance of a glow discharge quadrupole mass spectrometer is demonstrated using sintered tungsten as an example. The inherent problem of molecular interferences in glow discharge mass Spectrometry has been considerably reduced using neon as a complementing discharge gas. Particular attention has been paid to time dependences. Analytical figures of merit are presented. 相似文献
66.
Masao Matsuoka Tsuyoshi Matsuda June Tamaki Yoshifumi Yamamoto Chiaki Iwakura 《Research on Chemical Intermediates》2006,32(5):389-402
Laves-phase hydrogen storage alloy has a high potential for use as negative electrode material as alternative for the misch-metal-based
material. In order to improve the energy density and the rate capability of negative electrode, chemical and mechanical modification
of Lavesphase alloy with different stoichiometric ratios was carried out. Discharge capacity and high-rate dischargeabilty
was evaluated by electrochemical methods and the characterization of Laves-phase alloy was made by X-ray diffraction, SEM
observation and PCT measurement. The best result in discharge capacity could be obtained for stoichiometric Laves-phase alloy
with a composition of Zr0.9Ti0.1Ni1.1Co0.1Mn0.5V0.2Cr0.1 by boiling in 10 M KOH solution. On the other hand, the high-rate dischargeability was increased remarkably by introducing
mechanical grinding before alkali treatment. The cause for improved performance was discussed on the basis of thermodynamic
stability of metal hydride and changes in crystal structure and surface morphology influencing on diffusion coefficient and
diffusion path length of hydrogen. 相似文献
67.
R. D. Apostolova I. V. Kirsanova E. M. Shembel 《Russian Journal of Electrochemistry》2006,42(2):173-182
Electrolytic (e) cobalt oxide of a spinel structure, e-Co3O4, is obtained from the sulfate and nitrate (aqueous, water-alcohol) solutions containing Co2+ with the aim of using it in thin-layer anodes of lithium-ion batteries. The physicochemical and structural properties of the synthesized compounds are examined using thermal and x-ray diffraction analyses, absorption IR spectroscopy, and atomic force microscopy. The electrochemical characteristics of e-Co3O4 are determined in breadboards of lithium power sources and in the lithiumion system LiCoO2/e-Co3O4. 相似文献
68.
《Journal of Saudi Chemical Society》2020,24(9):673-682
A single dielectric barrier discharge (DBD) low-temperature plasma reactor was set up, and toluene was selected as the representative substance for volatile organic compounds (VOCs), to study the reaction products and degradation mechanism of VOCs degradation by low-temperature plasma. Different parameters effect on the concentration of O3 and NOx during the degradation of toluene were studied. The exhaust in the process of toluene degradation was continuously detected and analyzed, and the degradation mechanism of toluene was explored. The results showed that the concentration of O3 increased with the increase of the power density and discharge voltage of the plasma device. However, as the initial concentration of toluene increased, the concentration of O3 basically keep steady. The concentration of NOx in the by-products increased with the discharge voltage, power density, and initial concentration of toluene in the plasma device, and the concentration of NO2 was much higher than the concentration of NO. The degradation process of toluene was detected and analyzed. The results showed that the degradation mechanism of toluene by plasma includes high energy electron bombardment reaction, active radical reaction and ion molecule reaction. Among them, the effect of high-energy electrons on toluene degradation is the largest, followed by the effect of free radicals, in which oxygen radicals participated in the reaction mainly through the formation of C–O bond, CO bond, (CO)–O– bond and –OH radical, while nitrogen radicals participate in the reaction mainly through the formation of C–NH2, (CNH)- bond, CN bond and C–NO2 bond. The results can provide some data supports for the study of low-temperature plasma degradation of VOCs. 相似文献
69.
Quadrupole mass spectrometry has been employed to characterize the ionic species in the discharges of pure CH4, CH4/H2, and CH4/Ar systems. For pure methane, the major positive ions in the discharge at low pressure (e.g., 0.15 torr) are CH
3
+
, C2H
3
+
, CH
2
+
, C2H
2
+
, CH
4
+
, C2H
4
+
, and C2H
5
+
at high pressure (e.g., 0.5 torr) the major ions are CH
3
+
, C2H
3
+
, C2H
5
+
, C3H
3
+
, C H3H
7
+
, C4H
7
+
, C5H
7
+
, C6H
5
+
, and C7H
7
+
. The relative abundances of C1 ions decrease with increasing pressure, whereas those of higher-order ions increase with pressure. For 5% CH4 + 95% H2 mixture, in addition to those sampling from the pure methane plasma at the lower pressure, H
n
+
ions have also been detected. For 5% CH4 +95% Ar mixture, the principal ions are CH
3
+
, CH
2
+
, CH+, CH
5
+
, Ar+, and ArH+; the ions containing more than two carbon atoms are negligible. In these discharges, the CH
3
+
and C2H
3
+
are the most important positive ions in C1 and C2 ions, respectively. The ions detected are believed to come from the sheath between the electrode and the luminous plasma, and have high kinetic energy. An ion-molecule reaction mechanism is proposed which can well explain the observed main features of ionic products.Died June 1, 1991. 相似文献
70.
The effects of high-voltage pulsed discharge (HVPD) activation on the Raman spectra of saturated aqueous solutions of lithium sulfate (Li2SO4/H2O) in the range of the ν1(A) totally symmetric vibrations of the SO 4 2? anion and on the spectra of potassium thiocyanate KSCN/H2O in the region of the ν1(C≡N) vibrations of the SCN? anion have been studied. The temperature dependences of the width and frequency of the corresponding spectral lines have been investigated. 相似文献