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1.
The quasi-classical trajectory calculations based on extended London-Eyring-Polanyi-Sato potential energy surface have been used to study the reaction of Ba+HI→BaI+H system. The rotational, vibrational, translational, and angular distributions of the product BaI have been calculated. The calculated results are in good agreement with the experimental ones.  相似文献   

2.
Intr0ducti0nThereactionofvariousmolecularandatomicspecieswithsulfurdioxidehasbeenthesubjectofmanykineticstudiesmainIybecauseofitsinvolvementinmany0fthechemi-calreacti0ns0ccurringintheupperatmosphereandals0becauseofitsindustrialsignifi-cance.I-2Theintermediatesinv0lvedinthereactionareusuallynotdirectlyobservable.Forexample,thegeometryoftheSO2.Hadductisuncertain.TwopossiblestructUreshavetheHat0mbondedeithert0theSat0m,representedasHSO2,orbondedtoan0atom,representedasHOSO.ThestructUresaresh…  相似文献   

3.
A theoretical approach to polycondensation reaction of Aa-Bb type Involving intramolecular cycllzatlon has been proposed by Tang Au-chin et al.. In this paper, the theoretical sol-gel distribution is tested by polycondensation of adipic acid with trimethylol propane in a sto-ichiometric ratio of 0. 8, and the effect of intramolecular cyclization is discussed in detail.  相似文献   

4.
The mode selectivity of the H+CH3D→H2+CH2D reaction was studied using a recently developed ten-dimensional time-dependent wave packet method.The reac-tion dynam...  相似文献   

5.
The ab initio method has been used to study the 1-3 H transfer reaction on formamidine substituted by halogen. The calculation results show that the substituted halogen has two effects on the 1-3 H transfer reaction: decreasing the activation energy and stabilizing the C=N double bond owing to the conjugative effect of p-π-p of products and transition states.  相似文献   

6.
Sulphamic acid (H2NSO3H) was found to be an efficient catalyst for the multicomponent condensation reaction of β-naphthol, aromatic aldehydes and urea or amides to afford the corresponding α-amidoalkyl-β-naphthols in good yields. The remarkable features of this new procedure are high conversions, short reaction time, clean reaction profiles and simple experimental and work-up procedures.  相似文献   

7.
The potential energy surface (PES) for the reaction of E,E-pentadienyl with molecular oxygen was theoretically studied at the G3B3//B3LYP/6-311G(d,p) level of theory. The first step of the reaction was found to be the direct adduction of molecular O2 on either the C1 or the C3 atoms of E,E-pentadienyl, forming two C5H7O2· isomers. These two C5H7O2· isomers undergo a series of isomerization processes through either the hydrogen-transfer or cyclization pathway. In the final step, the hydrogen-transferred and cyclized isomers decompose into unsaturated aldehydes, unsaturated ketones, and hydroxyl radicals. Involves 20 stable species and 14 transition states, and the energies and structures of all reactants, products and transition states were calculated. Based on the calculated barriers and heats of formation, the authors suggest that the C2H3O·+C3H4O formation channel is the dominant channel for the C5H7·+O2 reaction. The possible existence of C5H7O2· radicals as long lifetime intermediates is also proposed, which is consistent with the recent photoionization mass spectrometric experiments by Zils et al.  相似文献   

8.
Through kinetic method, the reaction mechanism and the rate equations of chlorination of polyethylene are suggested in this paper. The rate of chlorination is second order with respect to the concentration of methylene remained and chlorine, respectively. Apparent changes in crystallinity during chlorination processes were determinated by differential scanning calorimetry(DSC). The mathematical model relating crystallinety with kinetic parameters and function of sequence length distribution are derived.  相似文献   

9.
The reaction of -arylacryloyloxiranes with phenythydrazine under the conditions of acid catalysis leads to 3 arylvinyl-I-phenylpyrazoles and 2-hydroxymethyl-5-aryl-1,4-pentadien-3-one phenythydrazones.Belorussian State Technological University. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3 pp. 324–327, March, 1996. Original article submitted June 26, 1995.  相似文献   

10.
3-(-Vinyloxyalkylimino)-2,3-dihydroindol-2-ones and 3-(vinyloxyphenylimino)-2,3-dihydroindol-2-ones were synthesized in 34-93% yield by reactions of -aminoalkyl and aminophenyl vinyl ethers with isatin.  相似文献   

11.
Hydrogen peroxide was found to activate iodine in the addition reaction with triple bonds. A facile and technologically straightforward procedure was developed for the synthesis of E‐diiodoalkenes based on the reaction of alkynes with an I2–H2O2 system in THF. Selective iodination of terminal and internal alkynes containing electron‐donating and electron‐withdrawing substituents afforded 16 E‐diiodoalkenes in yields up to 89%.  相似文献   

12.
AlkylationofBenzenewithPropeneoverHβZeolite──TheEffectofReactionConditionsontheDistributionofProductsMAJun,SHENJian-ping,SUNT...  相似文献   

13.
TrichlorosilaneisanimportantmaterialinplasmaChemicalVaporDeposition (CVD)andinsemiconductordeviceprocess .1 4 Thereactionoftrichlorosilanewithatomichydrogen ,thesimplestfree radicalspecies,hasdrawnconsiderableattention :kineticparametersforH atomreactionared…  相似文献   

14.
胡春丽  陈勇  李俊篯 《结构化学》2009,28(2):240-244
The adsorption and decomposition of H2O on GaN(0001) surface have been explored employing density functional theory (DFT). Two distinct adsorption features of H2O on GaN(0001) corresponding to molecular adsorption and H-OH dissociative adsorption are revealed by our calculations. The activities of the surface reactions of H2O on GaN(0001) surface are investigated. For the stepwise processes of H2O decomposition into H2 in gas phase and adsorbed O atom (H2O(g)→H2O(chem)→OH(chem) + H(chem)→2H(chem) + O(chem)→H2(g) + O(chem)), the first and second steps are facile and can even occur at room temperature; while the last two have high barriers and thus are difficult to proceed, especially the fourth step is endothermic. In short, H2O adsorption and decomposition into H2 in gas phase and adsorbed O atom on GaN(0001) surface are exothermic by -43.98 kcal/mol.  相似文献   

15.
孙仁安  李钠  艾纯芝  张宏 《结构化学》2006,25(4):491-496
1 INTRODUCTION Semiconductor silicon materials are vital for mi- croelectronic and information industry. Silicon has many advantages, for example, rich resource, out- standing quality and sophisticated processing tech- nology. So it has been widely used in semiconduc- tor industry. One of the key techniques of mo- dern microelectronic industry is epitaxial growth of single crystal thin film on single crystal silicon and its ba- cking materials. In the chemical vapour deposition of Si, g…  相似文献   

16.
17.
The enthalph change of reaction of zinc chloride with L-α-histidine in the temperature range of 25-50℃ has been determined by a microcalorimeter.On the basis of experimental and calculated results,three thermodynamics parameters (the activation enthalpy,the activation entropy,the activation free energy),the rate constant and three kinetic parameters (the activation energy,the pre-exponential constant and the reaction order) of the reaction,and the standard enthalpy of formation of Zn(His)^2 (aq.) are obtained.The results showed that the title reaction easily took place at the studied temperature.  相似文献   

18.
The reagent rotational excitation effect on the stereodynamics of H+LiF→HF+Li is calcu-lated by means of the quasi-classical trajectory method on the Aguado-Paniagua2-potential energy surface (AP2-PES) constructed by Aguado et al. [J. Chem. Phys. 106, 1013 (1997)]. The angular distributions of vector correlations between products and reactants, P(?r) and P(Φr) are presented. Meanwhile, the four polarization-dependent generalized differential cross sections are computed. The results indicate that the reagent rotational quantum num-bers have impact on the vector properties of the title reaction. In addition, the reaction probability has been calculated as well.  相似文献   

19.
IntroductionDicyclopentadiene(hereafterreferredtoasDCPD)isareadilyavailableolefinmon0merfoundintheoffstream0fpetrochemicalrefiners.P0lydicyc0lpentadiene(PDCPD)canbesynthesizedbymetathesispolymerization(l)whichisanexothermic,veryfastreacti0nevenatlowtemperatUres,andthereactionis'initiatedinstantaneouslybyaddingthecatalyst.Thecatalystspreferredforp0lymerization0fDCPDaremetathesiscatalystswhicharecomPrised0ftw0partS.Onepartc0ntalnsthetransitionmetalhalidewhichisthecatalyst,andtheotherisac0…  相似文献   

20.
Asoneofthemostimpoftantmethodofconstructionofheterocycles,theheteroDiels-##DAlderreactionhasbeenstudiedextensively'.ItwasalsoreportedwidelythatconjugatedindnesandenoletherswereinvolvedintheDiels-Alderreactionasdienesanddienenophilesrespectively'.Actually,asearlyasinthe6O'sand7O's,aromaticSchiffbasesandcyclicenolethershadalreadybeenusedinthesynthesisofsomepolyheterocycliccompoundswithbiologicalactivities3.Intheattemptofalkylationofcompound1inTHF,unexpectedlypolycycliccomPound3wasseparatedi…  相似文献   

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