To study the measurement of distance under the condition of the frequency modulation (FM) multi component signal of a short range radar, the multi points scattering model of a target, the TLS ESPRIT (total least sq...To study the measurement of distance under the condition of the frequency modulation (FM) multi component signal of a short range radar, the multi points scattering model of a target, the TLS ESPRIT (total least square estimation of signal parameters via rotational invariance techniques) and the mathematical statistics methods were used. The method of computing single frequency signal's instantaneous frequency (IF) is unsuitable to the multi component signal. By using the method of the TLS ESPRIT combined with the mathematical statistics, the multi component signal's IF can be obtained. The computer simulation has shown that the method has the high accuracy for measuring the distance.展开更多
Organofluorine compounds are widely used in the realm of drug discovery and material science.Herein,we developed palladium catalyzed intermolecular aminofluorination and oxy-aminofluorination of gem‑difluoroalkenes wi...Organofluorine compounds are widely used in the realm of drug discovery and material science.Herein,we developed palladium catalyzed intermolecular aminofluorination and oxy-aminofluorination of gem‑difluoroalkenes with N-fluorobenzenesulfonimide(NFSI),in which NFSI was used as the nitrogen source and oxidant.The reaction provides an efficient and straightforward synthesis route of a series ofα-trifluoromethyl benzylic amines.Notably,three/four components oxy-aminofluorination processes were realized to giveα-trifluoromethyl benzylic ether with a terminal amino group,which proceed through C(sp^(3))-O bond cleavage of easily available ether and simultaneous introduced a fluorine,an amino and an oxy substituent in one pot with excellent regioselectivity.The divergent reactivity not only included the incorporation of one ether molecular,but also much more challenged two ether insertion with excellent selectivity through succession C(sp^(3))-O bonds cleavage.This protocol allows for concise synthesis of high value amines with fluoroalkyl-substituents and selectively transformation of easily available ethers by high-valent palladium catalysis.展开更多
A simple, multi component, one-pot method has been reported for the synthesis of poly substituted imidazoles in presence of magnetically separable and recyclable spinel nano copper ferrite as heterogeneous catalyst by...A simple, multi component, one-pot method has been reported for the synthesis of poly substituted imidazoles in presence of magnetically separable and recyclable spinel nano copper ferrite as heterogeneous catalyst by the cyclo-condensation of benzil, aromatic aldehyde, ammonium acetate and substituted amines under ultrasonic irradiation. This method of preparation has many advantages compared to those methods which are previously reported in the literature. This methodology offers simple experimental procedure, milder reaction conditions and environmentally benign approach.展开更多
The influences of micro alloy and heat treatment procedure on the hardening of DJ108Ti alloy, which is based on the electrolytic Al Si(2 05%) Ti(0 25%) Fe(0 30%) multi component alloy, have been investigated...The influences of micro alloy and heat treatment procedure on the hardening of DJ108Ti alloy, which is based on the electrolytic Al Si(2 05%) Ti(0 25%) Fe(0 30%) multi component alloy, have been investigated. The results indicate that the micro alloy based on the multi component alloy makes α Al dendrites in DJ108Ti alloy refined; that the improved heat treatment procedure makes the eutectic Si phases granulated , the Fe phase refined, and the strengthening phases of Mg2Si and Al2Cu fully precipitated. The micro alloy and the heat treatment procedure harden DJ108Ti alloy and benefit the abrasion resistance of the alloy展开更多
Twenty 2,3-disubstituted-4（3H）-quinazolinones were synthesed by one-pot three-component method with isa- toic anhydride, orthoesters and amines as raw materials in the presence of KAI（SO4）2·12H2O （Alum） und...Twenty 2,3-disubstituted-4（3H）-quinazolinones were synthesed by one-pot three-component method with isa- toic anhydride, orthoesters and amines as raw materials in the presence of KAI（SO4）2·12H2O （Alum） under micro- wave irradiation and solvent-free conditions. 6-Bromo-2-propyl-3-p-tolylquinazolin-4（3H）-one （4m）, 6-bromo-2- methyl-3-phenethylquinazolin-4（3H）-one （4n） and 6-bromo-2-ethyl-3-phenethylquinazolin-4（3H）-one （40） were characterized by IR, 1H NMR, 13C NMR and elemental analysis.展开更多
The cumulative landfill gas （LFG） production and its rate were simulated for pretreated municipal solid waste （MSW） landfill using four models namely first order exponential model, modified Gompertz model, single ...The cumulative landfill gas （LFG） production and its rate were simulated for pretreated municipal solid waste （MSW） landfill using four models namely first order exponential model, modified Gompertz model, single component combined growth and decay model and Gaussian function. Considering the behavior of the pretreated MSW landfill, a new multi component model was based on biochemical processes that occurring in landfilled pretreated MSW. The model was developed on the basis of single component combined growth and decay model using an anaerobic landfill simulator reactor which treats the pretreated MSW. It includes three components of the degradation i.e. quickly degradable, moderately degradable and slowly degradable. Moreover, the devel- oped model was statistically analyzed for its goodness of fit. The results show that the multi components LFG production model is more suitable in comparison to the simulated models and can efficiently be used as a modeling tool for pretreated MSW landfills. The proposed model is likely to give assistance in sizing of LFG collection system, generates speedy results at lower cost, improves cost-benefit analysis and decreases LFG project risk. It also indicates the stabilization of the landfill and helps the managers in the reuse of the landfill space. The proposed model is limited to aerobically pretreated MSW landfill and also requires the values of delay times in LFG productions from moderately and slowly degradable fractions ofpretreated MSW.展开更多
基金Doctoral Programme Foundation of Institution of Higher Education of China.
文摘To study the measurement of distance under the condition of the frequency modulation (FM) multi component signal of a short range radar, the multi points scattering model of a target, the TLS ESPRIT (total least square estimation of signal parameters via rotational invariance techniques) and the mathematical statistics methods were used. The method of computing single frequency signal's instantaneous frequency (IF) is unsuitable to the multi component signal. By using the method of the TLS ESPRIT combined with the mathematical statistics, the multi component signal's IF can be obtained. The computer simulation has shown that the method has the high accuracy for measuring the distance.
基金supported by the National Natural Science Foundation of China(Nos.82130103,U1804283,21801067)the Central Plains Scholars and Scientists Studio Fund(No.2018002)+2 种基金the Project funded by the Natural Science Foundation of Henan Province(Nos.202300410225,222102310562)Henan Postdoctoral Science Foundation(No.202103087)the financial support from Henan Key Laboratory of Organic Functional Molecules and Drug Innovation.
文摘Organofluorine compounds are widely used in the realm of drug discovery and material science.Herein,we developed palladium catalyzed intermolecular aminofluorination and oxy-aminofluorination of gem‑difluoroalkenes with N-fluorobenzenesulfonimide(NFSI),in which NFSI was used as the nitrogen source and oxidant.The reaction provides an efficient and straightforward synthesis route of a series ofα-trifluoromethyl benzylic amines.Notably,three/four components oxy-aminofluorination processes were realized to giveα-trifluoromethyl benzylic ether with a terminal amino group,which proceed through C(sp^(3))-O bond cleavage of easily available ether and simultaneous introduced a fluorine,an amino and an oxy substituent in one pot with excellent regioselectivity.The divergent reactivity not only included the incorporation of one ether molecular,but also much more challenged two ether insertion with excellent selectivity through succession C(sp^(3))-O bonds cleavage.This protocol allows for concise synthesis of high value amines with fluoroalkyl-substituents and selectively transformation of easily available ethers by high-valent palladium catalysis.
文摘A simple, multi component, one-pot method has been reported for the synthesis of poly substituted imidazoles in presence of magnetically separable and recyclable spinel nano copper ferrite as heterogeneous catalyst by the cyclo-condensation of benzil, aromatic aldehyde, ammonium acetate and substituted amines under ultrasonic irradiation. This method of preparation has many advantages compared to those methods which are previously reported in the literature. This methodology offers simple experimental procedure, milder reaction conditions and environmentally benign approach.
文摘The influences of micro alloy and heat treatment procedure on the hardening of DJ108Ti alloy, which is based on the electrolytic Al Si(2 05%) Ti(0 25%) Fe(0 30%) multi component alloy, have been investigated. The results indicate that the micro alloy based on the multi component alloy makes α Al dendrites in DJ108Ti alloy refined; that the improved heat treatment procedure makes the eutectic Si phases granulated , the Fe phase refined, and the strengthening phases of Mg2Si and Al2Cu fully precipitated. The micro alloy and the heat treatment procedure harden DJ108Ti alloy and benefit the abrasion resistance of the alloy
文摘Twenty 2,3-disubstituted-4（3H）-quinazolinones were synthesed by one-pot three-component method with isa- toic anhydride, orthoesters and amines as raw materials in the presence of KAI（SO4）2·12H2O （Alum） under micro- wave irradiation and solvent-free conditions. 6-Bromo-2-propyl-3-p-tolylquinazolin-4（3H）-one （4m）, 6-bromo-2- methyl-3-phenethylquinazolin-4（3H）-one （4n） and 6-bromo-2-ethyl-3-phenethylquinazolin-4（3H）-one （40） were characterized by IR, 1H NMR, 13C NMR and elemental analysis.
文摘The cumulative landfill gas （LFG） production and its rate were simulated for pretreated municipal solid waste （MSW） landfill using four models namely first order exponential model, modified Gompertz model, single component combined growth and decay model and Gaussian function. Considering the behavior of the pretreated MSW landfill, a new multi component model was based on biochemical processes that occurring in landfilled pretreated MSW. The model was developed on the basis of single component combined growth and decay model using an anaerobic landfill simulator reactor which treats the pretreated MSW. It includes three components of the degradation i.e. quickly degradable, moderately degradable and slowly degradable. Moreover, the devel- oped model was statistically analyzed for its goodness of fit. The results show that the multi components LFG production model is more suitable in comparison to the simulated models and can efficiently be used as a modeling tool for pretreated MSW landfills. The proposed model is likely to give assistance in sizing of LFG collection system, generates speedy results at lower cost, improves cost-benefit analysis and decreases LFG project risk. It also indicates the stabilization of the landfill and helps the managers in the reuse of the landfill space. The proposed model is limited to aerobically pretreated MSW landfill and also requires the values of delay times in LFG productions from moderately and slowly degradable fractions ofpretreated MSW.
