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1.
The chlorine and bromine contents in tobacco and tobacco smoke in both the particulate and gaseous phases were studied by neutronactivation analysis. Methyl chloride and methyl bromide concentrations were measured in the gaseous phase by gas-liquid chromatography — mass spectrometry. The chlorine and bromine contents in nine brands of cigarettes were on the average as follows: Tobacco—6600 ppm chlorine and 110 ppm bromine. Cigarette smoke, particulate phase—68 g chlorine and 1 g bromine per cigarette. Cigarette smoke, gaseous phase—90 g chlorine and 5 g bromine per cigarette. In the gaseous phase methyl chloride accounted for 60% of the total chlorine and methyl bromine for 80% of the total bromine.  相似文献   

2.
Neutron activation analysis is practically the only high-sensitivy element-selective detection method for chlorine, bromine and iodine. This method is just ideal for organic halogen determination after separation of organically bound species from inorganic. In recent years we have analysed organic chlorine and bromine from thousands of different kind of samples with different separation methods. For water samples we have used activated-carbon adsorption and for solid samples mostly propanone or combined alkaline/propanone extraction before activated-carbon adsorption. Inorganic chlorides were removed from the carbon by nitrate wash. The detection limits for total organic chlorine and bromine are 5 and 0.5 g/l for water (sample size 100 ml) and 0.3 and 0.1 g/g dry weight (sample size 1 g) for sediment.  相似文献   

3.
The infrared spectra of H-forms of Y zeolite made from the guanidine and ammonium forms were compared. The Brönsted acid sites have been characterized by adsorption of pyridine. Good correlation between the concentration of Brönsted acid sites and the catalytic activity of the samples has been found. It was concluded that guanidine cations limited localization of OH groups on the surface of the supercages.
, . , . . , OH .
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4.
C-phenylcarbamoyl-N-phenylnitron and C(2,4-di-tert-butyl-3-hydroxyphenylcarbamoyl)-N-(p-di-methylaminophenyl) nitron inhibit the oxidation of solid polypropylene. In this case the nitrons studied demonstrate properties of polyfunctional inhibitors: they interrupt oxidation chains by chains by reactions with alkyl and peroxyl radicals.
C--N- C-(2,4----3-)-N-(-) . , .
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5.
Interaction of super-finely dispersed Al powders (SFDP) with water is characterized by the presence of a considerable section on the kinetic curves, where the conversion rate is maximum and its degree is as high as =0.5–0.7. It is suggested that the essential factor accounting for the conversion kinetics and the phase composition of its products is the self-heating of Al particles.
() , , () 0,5–0,7. , .
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6.
The reaction between ammonium sulphate with aluminium oxide was studied. It was confirmed by X-ray diffraction and chemical analysis that three intermediate reaction products, (NH4)3Al(SO4)3, NH4Al(SO4)2 and Al2(SO4)3, are formed. The thermal decompositions of these three compounds were carried out. It has been shown that the same rate law is valid for them. The activation energies for (NH4)3Al(SO4)3, NH4Al(SO4)2 and Al2(SO4)3 are 95.9, 177.9 and 291.0 kj/mol, respectively.
Zusammenfassung Die Reaktion von Ammoniumsulfat mit Aluminiumoxid wurde untersucht. Durch Röntgendiffraktion und chemische Analyse wurde bestätigt, daß drei Zwischenprodukte (NH4)3Al(SO4)3, NH4Al(SO4)2 und Al2(SO4)3 gebildet werden. Die thermische Zersetzung der drei Verbindungen wurde durchgeführt. Es wurde gezeigt, daß für alle drei dasselbe Geschwindigkeitsgesetz Gültigkeit hat. Die Aktivierungsenergien für (NH4)3Al(SO4)3, NH4Al(SO4)2 und Al2(SO4)3 sind 95.9, 177.9 und 291.0 kJ/Mol.

. - : (NH4)3Al(SO4)3, NH4Al(SO4)2 Al2(SO4)3. , , . (NH4)3Al(SO4)3, NH4Al(SO4)2 Al2(SO4)3, , 95.9; 177.9 291.0 . –1.


The authors are grateful to Dr. H. Osada and Mr. H. Nakamura, Department of Environmental Engineering, Kyushu Institute of Technology, for their helpful discussions.  相似文献   

7.
A previously suggested mechanism for the H-D isotope exchange of dihydrogen with aqueous alkaline and amide-ammonia solutions is discussed to be generalized and extended to hydrogen isotope exhange with other protolytic solvents.
- () - () - (). ().
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8.
Experimental data for the oxidative dimerization of methane over CaO–CaCl2 systems indicate that C2 hydrocarbons are formed with the participation of chlorine generated by the catalyst surface under the effect of a reaction medium. A heterogeneous-homogeneous scheme for this process is suggested.
CaO–CaCl2 , C2- , . - .
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9.
Ethylbromoacetate was pyrolyzed in a static system and seasoned vessels at temperatures between 339.3 °C–353.3 °C and pressures between 53–166.4 Torr. The rate constant for the homogeneous unimolecular elimination is given by the following Arrhenius equation: log k1(s–1)=(12.62±1.01)–(195.7±9.7) kJ/mol/2.303 RT. In comparing the -bromo substituent with the -chloro one in alkyl -monohaloacetates, the former shows about the same rate as the latter. The lack of a very significant difference in rates may be due to their similar electron withdrawing effect under these reaction conditions.
, , , 339,3 °C–353,3 °C 53–166,4 . : 10g1 (–1)=(12,62±1,01)–(195,7±9,7) ·–1/2,303RT. - - - . .
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10.
On the basis of n-decane transformation, the activity and selectivity of platinum catalysts containing HNaY, as a component of the carrier, were compared. The catalysts differed in the amount of the preserved crystalline structure of the Y-zeolite.
- , HNaY . Y.
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11.
The evaporation of potassium from phlogopite was investigated by roasting phlogopite with different chemical reagents. The possible reactions between reactants and the sample at different temperatures were investigated by thermogravimetry. Gypsum, calcite, sodium chloride, activated carbon, calcium chloride and fluoride were used as chemical reactants. Similar tests were carried out by batch experiments using muffle furnace and tube oven and finally the sample mixtures were heated in a vacuum. The use of a vacuum enabled an almost complete extraction of potassium in solid state at the lowest temperature so far investigated. The structure of phlogopite was shown to be destroyed by raising the temperature. The extraction of potassium from feldspar, a sample from Lohja, Finland was also investigated.
Zusammenfassung Beim Abrösten von Phlogopit mit verschiedenen chemischen Stoffen wurde das Verdampfen von Kalium aus Phlogopit untersucht. Die möglichen Reaktionen zwischen der Probe und der Reaktionspartnern bei verschiedenen Temperaturen wurden mittels Thermogravimetrie untersucht. Als Reaktant wurden Gips, Kalzit, Natriumchlorid, Aktivkohle, Kalziumchlorid und -fluorid verwendet. Ähnliche Untersuchungen wurden in Reihenexperimenten mittels Muffel- und Röhrenofen und letztlich durch Erhitzen der Proben im Vakuum durchgeführt. Die Anwendung von Vakuum ermöglicht bei den niedrigsten der angewendeten Temperaturen einen fast vollständigen Auszug des Kaliums aus dem Feststoff, Durch Erhöhen der Temperatur wurde die Struktur von Phlogopit nachweislich zerstört. Die Extraktion von Kalium aus einer Feldspatprobe aus Lohja, Finnland, wurde ebenfalls untersucht.

. . , , , , . , , . , , . , . //.
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12.
A study has been made of temperature programmed desorption (TPD) of NH3 and H2O from samples of NH4X and CoNH4X zeolites of various degree of exchange. NH3 TPD peaks could be explained by interaction of NH3 with different Brönsted and Lewis acidic centers. Moreover a water peak at high temperatures allowed interpretations of the dehydroxylation, and by reason of the characteristic desorption temperatures a particular state of the Co2+ ions in the CoNH4X zeolites is postulated.
- () NH3 H2O NH4X CoNH4X . NH3 NH3 =qs . . Co2+ CoNH4X.
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13.
The poisoning effect of thiophene, dichloroethane and heavy metal compounds on the catalytic activity of Renay nickel has been investigated and the catalytic activity correlated with the poison concentration. The poisoning occurs in the following order: Hg(II)-chloride>Zn-acetate> Hg(II)-acetate>dichloroethane>thiophene> >Pb-acetate.
, , . : Hg(II)->Zn->Hg(II)-> >>Pb-.
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14.
Six MoS2/SiO2 samples were characterized by XRD, BET surface area, ESR and NO adsorption measurements. Correlation was found between the amount of Mo5+, sulfur radicals and adsorption capacity for oxygen and NO.
MoS2/SiO2 , , , NO. Mo5+, NO.
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15.
Approximate equation to calculate the effectiveness factor of catalyst for SO2 oxidation to SO3 has been derived. Calculated data agree well with those predicted by a quasi-homogeneous model.
. .
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16.
Termination rate constants of peroxy radicals of seven polyatomic esters in benzene and perflouorooctane media have been measured by pulse photolysis. Recombination of peroxy radicals for all esters examined proves to be diffusion controlled. Reactivity of peroxy radicals in the termination reaction grows with increasing number of ester groups.
. . .
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17.
CH4 photooxidation on V/SiO2 catalyst in the presence of gaseous oxygen has been studied by the mass-spectometric method. It has been established that CO2 forms due to the interaction of CH4 with surface oxygen anions bonded to vanadium ions. Photodecomposition of V4+O 2 species formed in O2 adsorption on reduced vanadium ions leads to the reoxidation of the latter.
- CH4 V/SiO2 . , CO2 CH4 , . V4+O 2 O2 , .
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18.
The difference in reactivity of PdCl 4 2– and PdBr 4 2– species versus the Al2O3 hydrous surface was explained according to the trans-effect theory. It has important consequences on Pd uptake rates and impregnation profiles.
PdCl 4 2– PdBr 4 2– Al2O3 . Pd .
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19.
Pt–Re/Al2O3 prepared under different impregnating conditions were characterized by TPR and tested in naphtha and n-heptane reforming. Catalysts showed different Pt and Re radial distributions and reduction profiles. When both metals interact, higher dehydrocyclization and conversion are retained after a deactivation step, meanwhile, when Re is segregated from Pt the catalytic performance is negatively affected.
Pt–Re/Al2O3, , -. Pt Re . , , Re Pt .
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20.
The thermal behaviour of the solvates and mixed solvates in the LiCl(MgCl2, AlCl3)-water-1,4-dioxane systems was investigated by means of DTA measurements of the melting behaviour and by quasi-isothermal and quasi-isobaric investigations of the thermal decomposition processes.The compounds melt incongruently. The positions of the melting points and the processes of thermal decomposition confirm the assumption that 1,4-dioxane is bonded in the first coordination sphere in the mixed solvate of lithium, but in the cases of magnesium and aluminium chloride it is bonded via hydrogen-bonds and not directly to the cations. Only for the lithium and magnesium compounds does the decomposition of the anhydrous solvates result in anhydrous chlorides.
Zusammenfassung Das thermische Verhalten der Solvate und Mischsolvate der Systeme LiCl, (MgCl2, AlCl3)-Wasser-1,4 Dioxan wurde mit Hilfe von DTA-Messungen zum Schmelzverhalten, und quasi-isothermen und quasi-isobaren Untersuchungen zum Ablauf der thermischen Zersetzung Untersucht. Die Verbindungen schmelzen inkongruent. Die Lage der Schmelzpunkte und der Verlauf der thermischen Zersetzung bekräftigen die Vorstellungen, daß 1,4 Dioxan im Mischsolvat des Lithiums in der ersten Koordinationsphäre direkt am Kation, hingegen bei Magnesium und Aluminium über Wasserstoffbrücken gebunden ist. Die Zersetzung der wasserfreien Solvate führt nur im Fall der Lithium- und Magnesiumverbindungen zu den wasserfreien Chloriden.

( , )--1,4- , - - — . . , 1,4- . , , . .


The valuable assistance of Dr. Frahghänel in the separation of the solid phase by means of the hightemperature centrifuge is gratefully acknowledged.  相似文献   

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