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1.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, p. 2879, December, 1988.  相似文献   

2.
The preparation of C8H8Cr(CO)3 (or C8H8Cr(PF3)3) and polystyrenechromium tricarbonyl (or polystyrenechromium tris(trifluorophosphine) from chromium atoms, styrene and carbon monoxide (or trifluorophosphine) is described; nickel atoms and styrene produce tristyrenenickel, which reacts with α,α′-bipyridyl to yield bipyridylstyrenenickel.  相似文献   

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Dynamic restructuring of the Ag(111) surface occurs during the reaction of sulfur dioxide with Ag(111)-p(4 x 4)-O at 300 K, resulting in the incorporation of added silver atoms into the unit cells of both adsorbed sulfite and sulfate. This result clearly demonstrates that incorporation of metal atoms into the structures of adsorbates and reaction intermediates is not restricted to more open, higher free energy single crystal planes. These observations indicate that the participation of added metal atoms must be considered in the theoretical treatment of metal catalyzed reactions.  相似文献   

5.
The interaction of hydrogen atoms with a variety of alkali metal and alkaline-earth metal salts results not only in the recombination of these atoms but also in the displacement, into the gas phase, of free radicals (CaCl·(A 1 P 1/2, B 2 S +) and CaF·(A 2 P)) and metal atoms, including their excited species, which are detected spectroscopically. Transmission spectra indicate that the NaCl surface undergoes metallization when treated with a high-frequency discharge and a rarefied hydrogen flame. Combustion is affected by the gas-phase hydrogen atoms involved in the chain reaction and by the varying composition and properties of the surface. The concentration of Na atoms over the NaCl surface at 770 K is 109?1011 cm?3 in a stream of H atoms at 1 Torr and in the 2H2 + O2 flame at 4 Torr. The concentration of sodium atoms in the 2 P 3/2 and 2 P 1/2 excited states is ~5 × 106?5 × 108 cm?3. The role of the discovered reactions in combustion, pyrolysis, and plasma chemistry is discussed.  相似文献   

6.
The profound effect of stirring on chemiluminescence of the system: bromate-malonic acid-ruthenium complexes with low (10–5 M) catalyst concentrations indicates the significant contribution of organic radicals R. to the oscillation mechanism. Critical radical concentration for this oscillation is [R.]C<7×10–10 M.
: - - (10–5 M) . R. : [R.]C<7×10–10M.
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7.
Due to strong photoluminescence, extraordinary photostability, excellent biocompatibility, and good water-solubility, metal nanoclusters have attracted enormous attention since discovered. They are found to be novel fluorescence labels for biological applications and environmental monitoring. Recently the chemiluminescence (CL) or electrochemiluminescence (ECL) of metal nanoclusters has received increasing attention. This review covers recent vibrant developments in this field of the past 5 years, and highlights different functions of metal nanoclusters in various CL and ECL systems, such as luminophores, catalysts, and quenchers. Latest synthetic methods of metal nanoclusters used in CL or ECL are also summarized. Furthermore, we discuss some perspectives and critical challenges of this field in the near future.  相似文献   

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Oxygen atoms are detected by NO + O + M chemiluminescence as a secondary product of the reaction between Cl and O3. The mechanism Cl + O3 → ClO + O2(1Σ+g), O2(1Σ+g) + O3 → O2 + O2 + O is proposed to account for the oxygen atom formation. The branching ratio to the O2(1Σ+g) product in the reaction of Cl with O3 is estimated to be in the range (0.1–0.5) x 10?2.  相似文献   

10.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, p. 2667, November, 1990.  相似文献   

11.
在甲醛存在下,KMnO4与茚三酮能够发生化学发光反应,产生很强的化学发光.据此采用流动注射技术,建立了一种利用KMnO4-甲醛-茚三酮化学发光体系测定茚三酮的方法.方法的检出限为3×10-8 g/mL;相对标准偏差为1.1%(4.0×10-6g/mL茚三酮,n=11);线性范围为1.0×10-7~2.0×10-4 g/mL.本法已用于样品中茚三酮的测定.  相似文献   

12.
Radiative recombination of chlorine atoms is experimentally studied. Non-equilibrium atom concentrations are obtained by thermal dissociation of Cl2 in a shock tuba followed by fast cooling in a supersonic nozzle. Recombinative emission at high (above 1017 cm?3) non-equilibrium atom concentrations is experimentally observed for the first time. The emission is in the near IR (8000–10500 Å).  相似文献   

13.
流动注射化学发光法测定硫脲   总被引:2,自引:0,他引:2  
在酸性介质中,KMnO4能够氧化硫脲产生化学发光,表面活性剂十六烷基三甲基溴化铵对该发光体系有增敏作用,据此,建立了测定硫脲的流动注射化学发光新方法.方法线性范围为4.O×10-7 ~4.0×10-4mol/L,检出限为2.0×10-8 mol/L,对1.0×10-5 mol/L的硫脲平行测定11次,相对标准偏差为1....  相似文献   

14.
The reaction between formaldehyde and ammonia   总被引:1,自引:0,他引:1  
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Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1934–1935, August, 1991.  相似文献   

17.
The reaction of dimethyldioxirane (1) with the RuII trisbipyridyl complex accompanied by chemiluminescence (CL) was studied. It is established that the intensity of CL and the rate of its decay increase proportionally with the concentration of RuII. The bimolecular rate constant (k 2) of the reaction of1 with RuII was determined. The activation parameters (E a and logA) for this reaction were calculated from the temperature dependence ofk 2. The excitation yield of RuII*Ru * ) was estimated. The quenching of RuII* by dioxirane was studied, and the bimolecular quenching constant and the coefficient of excitation regeneration were determined. It was suggested that the catalysis of the decomposition of1 and the excitation of RuII occurvia a mechanism of chemically initiated electron exchange. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1138–1142, June, 1997.  相似文献   

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The binding of a single metal atom (Pt, Pd, Au, and Sn) nearby a single-vacancy (SV) on the graphene is investigated using the first-principles density-functional theory. On the pristine graphene (pri-graphene), the Pt, Pd, and Sn prefer to be adsorbed at the bridge site, while Au prefers the top site. On the graphene with a single-vacancy (SV-graphene), all the metal atoms prefer to be trapped at the vacancy site and appear as dopants. However, the trapping abilities of the SV-graphene are varied for different metal atoms, i.e., the Pt and Pd have the larger trapping zones than do the others. The diffusion barrier of a metal atom on the SV-graphene is much higher than that on the pri-graphene, and the Pt atom has the largest diffusion barrier from the SV site to the neighboring bridge sites. On the SV-graphene, more electrons are transferred from the adatoms (or dopants) to the carbon atoms at the defect site, which induces changes in the electronic structures and magnetic properties of the systems. This work provides valuable information on the selectivity of lattice vacancy in trapping metal atoms, which would be vital for the atomic-scale design of new metal-carbon nanostructures and graphene-based catalysts.  相似文献   

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