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111.
The (Z)-4-(phenylamino) pent-3-en-2-one (PAPO) was synthesised applying carbon-based solid acid and described by experimental techniques. Calculated results reveal that its keto-amine form is more stable than its enol-imine form. A relaxed potential energy surface scan has been accomplished based on the optimised geometry of NH tautomeric form to depict the potential energy barrier related to intramolecular proton transfer. The spectroscopic results and theoretical calculations demonstrate that the intramolecular hydrogen bonding strength of PAPO is stronger than that in 4-amino-3-penten-2-one)APO(. In addition, molecular electrostatic potential, total and partial density of stats (TDOS, PDOS) and non-linear optical properties of the compound were studied using same theoretical calculations. Our calculations show that the title molecule has the potential to be used as molecular switch. 相似文献
112.
113.
In this work, an experimental study of spray impact onto a horizontal flat and rigid surface is presented. The phase Doppler
technique has been used to characterize both the impacting and the secondary spray in terms of mass and number flux, size
distribution and velocities of the droplets above the target. A high-resolution CCD camera has been used to measure the average
liquid film thickness formed due to spray impact, whereas a high-speed CMOS camera has been used to characterize the splashing
droplets from the wall. This visualization of the splashing phenomenon and the knowledge about the liquid film thickness are
used to formulate a new physical model of the crown evolution. Furthermore, information about the incident-to-ejected mass
fraction and number fraction are novel contributions of this study. Considerable data are provided comparing the impact of
single drops onto a liquid film to impact of drops in a spray, and the significance of the observed differences for modelling
efforts is discussed. The measurements of this study are also shown to be rather sensitive to the placement of the phase Doppler
measurement volume above the surface and to the operating parameters of the instrument. These effects have been documented
and discussed for this particular measurement situation. 相似文献
114.
An experimental study of spray impact onto horizontal flat and rigid surfaces is presented and used as input data for a new empirical model. A phase Doppler instrument has been used to measure drop size and two components of velocity directly above the target. The average film thickness formed due to spray impact has been measured using a high-speed CCD camera. The spray–wall interaction has been characterized in terms of correlations for the velocity and trajectory of secondary droplets and the mass and number ratio of the secondary spray. The novel aspect of the model is that the correlations are based on mean statistics over many events and not on the outcome of single drop impact experiments. Furthermore a rather large range of oblique impact angles have been studied and incorporated into the empirical models as an influencing factor. 相似文献
115.
A convenient, one-pot, solvent-free reaction of amines, aromatic aldehydes, and Meldrum's acid to form 8-aryl-7,8-dihydro-[1,3]dioxolo[4,5-g]quinolin-6-(5H)-one and 4-aryl-3,4-dihydroquinolin-2-(1H)-one in the presence of 10 mol% ZrOCl2.8H2O under ultrasonic irradiation is described. This new protocol offers several advantages including low catalyst loading, clean reaction, easy workup, use of recyclable and ecofriendly catalyst, short reaction times, good yields, and solvent-free conditions. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献
116.
Hamidreza Ali-Asgari Dehaghi Saeedeh Mazinani Davood Zaarei Mohammadreza Kalaee Hamed Jabari Navid Sedaghat 《Journal of Thermal Analysis and Calorimetry》2013,114(1):185-194
Systematic study about the effect of acrylonitrile–butadiene rubber (NBR) concentration on the fracture toughness and thermal behavior of epoxy resin is conducted in this study. NBR is solved in an aromatic hydrocarbon solvent and is added to epoxy resin. We used diethylene-teriamin as the curing agent for epoxy resin. Tensile test results, performed followed by molding procedure, show that the toughness is improved owing to the increase of rubber content. Scanning electron microscopy (SEM) and atomic force microscopy besides thermogravimetric analysis (TG) are used to investigate the epoxy/rubber interface and chemical decomposition of the resultant mixture. The thermal behavior of cured epoxy resin was analyzed via TG instrument at different heating rates. Thermogravimetry curves showed that the thermal decomposition of epoxy system was occurred in only one stage regardless of the rubber content. The apparent activation energies of the rubber/epoxy systems containing 0, 5, and 10 phr of rubber were determined by Flynn–Wall–Ozawa, Kissinger–Akahira–Sunose, and Friedman methods. The results prove that the thermal stability of epoxy resin was decreased with enhancing the rubber content. However, the trend of changing activation energy versus conversions is totally different followed by adding the elastomer to the system compared to neat epoxy resin. Moreover, the results obtained via our proposed facile solution blending method are compared to those of resins modified with nano-powdered elastomer. 相似文献
117.
Esmael Rostami Abbas Shockravi Hanif Fattahi Davood Heydarian Shima Shahbanzadeh Minaee Shaghayegh Naghdi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):2066-2077
Dinaphthosulfone aza macrocycles were synthesized from the reaction of diamines and dinaphthosulfone diester (1,1′-sulfoxobis-(2-naphthoxy(2-methyl acetate))) in methanol in the presence of catalytic amounts of para toluenesulfonic acid (p-TsOH). Dinaphthosulfone diester (1,1′-sulfoxobis-(2-naphthoxy(2-methyl acetate))) was synthesized from the corresponding dinaphthosulfide diester and hydrogen peroxide in formic acid at room temperature. Dinaphthosulfide diester was prepared from initial dinaphtholsulfide diol (1,1′-thio bis(2-hydroxy naphthalene)) and methylchloroacetate. 1H NMR spectroscopy showed the unusual splittings for these dinaphthosulfone aza macrocycles, and this finding could be proposed as the role of tetrahedral structure of sulfone functional group, hydrogen bonding in the cavity and size of macrocycle. 相似文献
118.
Esmael Rostami Davood Heidaryan Hanif Fattahi Abbas Shockravi Mehdi Zarei Farokh Rakhshanderu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1924-1934
Four new dinaphthosulfide and dibenzosulfide aza podands were synthesized. The synthesis of these podands was performed under three different reaction conditions: 1) diester, K 2 CO 3 , methanol, and RT; 2) diester, ethanolamine, and microwave (MW); and 3) diacid dichloride, ethanolamine, Et 3 N, CH 2 Cl 2 , RT. Two kinds of diester (dinaphthosulfide and dibenzosulfide) were used for the preparation of dihydroxy podands. These dihydroxy podands were reacted with thionyl chloride to afford dichloro podands. The second route gave excellent yields of dihydroxy podands. Dichloro podands are more soluble than dihydroxy podands in conventional solvents such as methanol, chloroform, and acetonitrile. 相似文献
119.
Davood Nori-Shargh Hooriye Yahyaei Maryam Jafari Shamsi Rafatpanah Abbas Madhi Tazekand Seiedeh Negar Mousavi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1538-1553
Abstract The alkyl 1,2-shift in di-tert-butylcyclopenta-1,3-diene (1) and the metallotropic 1,2-shifts in bis(trimethylsilyl)cyclopenta-1,3-diene (2), bis(trimethylgermyl)cyclopenta-1,3-diene (3), and bis(trimethylstannyl)cyclopenta-1,3-diene (4) have been investigated by means of natural bond orbital (NBO), nuclear magnetic resonance (NMR) analysis, and hybrid density functional theory based methods. The B3LYP/DZVP results showed that the M(CH3)3 group [M = C (1), Si (2), Ge (3), and Sn (4)] migration barrier heights around cyclopentadienyl rings decrease from di-tert-butylcyclopenta-1,3-diene to its stannane derivative. Also, based on the results obtained, the stabilities of the 5,5-isomers in comparison to the 1,5- and 2,5-isomers increase from di-tert-butylcyclopenta-1,3-diene to its stannane derivative. The results suggest that in these compounds the metallotropic shifts are controlled by the stabilization energies associated with σ→π* electron delocalizations and the increase of the σC5-M→π*C1-C2 electron delocalizations facilitates the M(CH3)3 group migrations around cyclopentadienyl rings. Based on the aromatic stabilization energy (ASE) values calculated, the aromaticity increases from the 5,5-isomers of di-tert-butylcyclopenta-1,3-diene to its stannane derivative but the variation of the nucleus-independent chemical shift, NICS(0) and NICS(1), values calculated are not in accordance with the ASE values calculated and the σC5-M→π*C1-C2 electron delocalizations. The correlations between the sigmatropic shift barrier heights, σ→π* electron delocalizations, ASE, and NICS values were investigated. GRAPHICAL ABSTRACT 相似文献
120.
Davood Nematollahi Adel Ghorbani Amene Amani Hamid Salehzadeh Hadi Beiginejad 《中国化学快报》2013,24(3):205-207
The electrochemical oxidation of 2,5-dihydroxybenzoic acid (1) has been studied in the presence of 1,3-cyclopentadiene (2) as a diene in water/ethanol (40/60, v/v) mixture using cyclic voltammetry and controlled-potential coulometry. A plausible mechanism for the oxidation of 1 in the presence of 2 is presented. Compound 1 was converted into bis-adduct 5 via electrooxidation, Diels-Alder reaction of 2 to anodically generated 3,6-dioxocyclohexa-1,4-dienecarboxylic acid (1ox), decarboxylation reaction, electrooxidation and Diels-Alder reaction. The electrochemical synthesis of 5 was performed in a onepot reaction, without toxic reagents, at a carbon electrode in a simple cell using an environmentally friendly method. 相似文献