The hydrophobic flocculation flotation of rutile fines in the presence of styryl phosphonic acid（SPA） was investigated by flotation tests, zeta-potential measurement, optical microscope observation, laser-based part...The hydrophobic flocculation flotation of rutile fines in the presence of styryl phosphonic acid（SPA） was investigated by flotation tests, zeta-potential measurement, optical microscope observation, laser-based particle size analysis, adsorption measurements and DLVO theory. The flotation tests indicated that rutile fines could be flocculated by SPA, and pH, shear force（stirring speed） and stirring time played significant roles in flocculation. The isoelectric point（IEP） and zeta-potential in whole range all moved to negative values as SPA was added according to the results from zeta-potential measurement. It was demonstrated that the primary reason for above was chemical adsorption. The laser-based particle size results showed the particle size at a stirring speed of 1800 r/min and 1000 mg/L SPA was the largest in all experiments. Furthermore, using the optical microscope observation and flotation tests, it was important for flotation of rutile fines to produce the flocculant. In the light of above-mentioned facts, floc flotation of rutile fines could be induced in the form of chemical adsorption by SPA to increase particle size. The data calculated from DLVO theory also indicated that chemical adsorption was the main reason for the formation of flocculant.展开更多
In this paper, we review our recent progress in the synthesis and application of styryl-capped polypropylene （PP-t- St）, an excellent reactive polyolefin that is both convenient and efficient in synthesis and facile...In this paper, we review our recent progress in the synthesis and application of styryl-capped polypropylene （PP-t- St）, an excellent reactive polyolefin that is both convenient and efficient in synthesis and facile and versatile in application for preparing advanced polypropylene materials via macromolecular engineering. The synthesis of PP-t-St is made possible by a unique chain transfer reaction coordinated by a bis-styrenic molecule, such as 1,4-divinylbenzene （DVB） and 1,2-bis（4- vinylphenyl）ethane （BVPE）, and hydrogen in typical C2-symmetric metallocene （e.g. rac-Me2Si（2-Me-4-Ph-Ind）2ZrC12, in association with methylaluminocene, MAO） catalyzed propylene polymerization. The regio-selective 2,1- insertion of the styrenic double bond in DVB or BVPE into the overwhelmingly 1,2-fashioned Zr-PP propagating chain enables substantial dormancy of the catalyst active site, which triggers selective hydrogen chain transfer that, with the formed Zr-H species ultimately saturated by the insertion of propylene monomer, results in an exclusive capping of the afforded PP chains by styryl group at the termination end. With a highly reactive styryl group at chain end, PP-t-St has been used as a facile building block in PP macromolecular engineering together with the employment of state-of-the-art synthetic polymer chemistry to fabricate broad types of new polypropylene architectures.展开更多
Herein,styryl phosphonate monoester(SPE) was synthesized and first introduced as rare earth extractant.The solvent extraction of lanthanum(Ⅲ) from nitrate solution using styryl phosphonate mono-isooctyl ester(SPE108)...Herein,styryl phosphonate monoester(SPE) was synthesized and first introduced as rare earth extractant.The solvent extraction of lanthanum(Ⅲ) from nitrate solution using styryl phosphonate mono-isooctyl ester(SPE108),di-2-ethylhexyl phosphoric acid(D2 EHPA) and 2-ethylhexyl phosphonic acidmono-2-ethylhexyl ester(EHEHPA) as extractants was investigated.The effects of experimental parameters including equilibrium time,extractant concentration,aqueous pH,phase ratio and salt concentration on the extraction process were studied.The results indicate that the extraction ability and capacity of the extractants follow the order:SPE108> D2 EHPA> EHEHPA.What’s more,the extraction process is less affected by ammonium sulfate in the aqueous phase with SPE108.The results of the separation between lanthanum and adjacent lanthanides(Ce,Pr,Nd,Sm) show that SPE108 can separate lanthanides efficiently at low pH.The extraction mechanism of SPE108 is proved to be similar to D2 EHPA,and the density functional theory(DFT) calculation results infer that SPE108 exhibits superior extraction ability due to its strong electron-accepting ability.展开更多
Cysteine(Cys)-specific bioconjugation has widespread applications in the synthesis of protein conjugates,particularly for the functionalization of antibodies.Here,we report the discovery of transstyryl sulfonyl fluori...Cysteine(Cys)-specific bioconjugation has widespread applications in the synthesis of protein conjugates,particularly for the functionalization of antibodies.Here,we report the discovery of transstyryl sulfonyl fluoride(SSF)as a near-perfect Michael acceptor for Cys-specific protein bioconjugation.Compared to maleimides,which are predominantly used,SSF exhibited better chemoselectivity,selfstability,and conjugate stability while maintaining comparable reactivity.Using SSF-derived probes,proteins can be readily modified on the Cys residue(s)to install functionalities,for example,fluorescent dyes,toxins,and oligonucleotides,without influencing the activity.Further applications of SSF-derived serum-stable antibody-drug conjugates and PD-L1 nanobody-oligo conjugates demonstrate the great translational value of SSF-based bioconjugation in drug development and single-cell sequencing.展开更多
The reactions of 2-methylbenzimidazole or 2-methylbenzimidazolium iodide with aromatic aldehydes are accelerated under microwave irradiation by using Ac2O or piperidine as dehydrant or catalyst in the absence of any s...The reactions of 2-methylbenzimidazole or 2-methylbenzimidazolium iodide with aromatic aldehydes are accelerated under microwave irradiation by using Ac2O or piperidine as dehydrant or catalyst in the absence of any solvent. The approach provides an attractive and environmentally friendly pathway to several useful styryl dyes with benzimidazole nucleus.展开更多
The Palladium inserted hydridopalladium species represents as RCOOPdH. This work finds an interesting coupling of palladium inserted RCOOPdH species with potassium styryltrifluoroborates to synthesize new kinds of sty...The Palladium inserted hydridopalladium species represents as RCOOPdH. This work finds an interesting coupling of palladium inserted RCOOPdH species with potassium styryltrifluoroborates to synthesize new kinds of styryl ester compounds. Pd(OAc)<sub>2</sub> was most effective catalyst for this new cross-coupling reaction under microwave irradiation and gave styryl esters in good to moderate yields.展开更多
An amphiphilic benziminazole styryl dye, 2 (4 dihexadecylaminostyryl)benziminazolium TCNQ -(DBTCNQ), was synthesized and successfully transferred onto the substrates by Langmuir Blodgett(LB) technique. H aggregates we...An amphiphilic benziminazole styryl dye, 2 (4 dihexadecylaminostyryl)benziminazolium TCNQ -(DBTCNQ), was synthesized and successfully transferred onto the substrates by Langmuir Blodgett(LB) technique. H aggregates were formed on the substrates. Its monolayer second order susceptibility[ χ (2) zzz = 109 p/mV) was determined with a polarized laser beam(Nd∶YAG, λ =1.064 μm). The photoelectrochemistry of the dye LB monolayer films was investigated in a traditional three electrode cell. The quantum efficiency of photoelectric conversion is 1.08% under favorable conditions [-200 mV, 0.5 mg/mL methylviologen diiodide(MV 2+ ) in 0.5 mol/L KCl electrolyte solution]. The experimental data indicate that the LB film exhibits multifunctional properties.展开更多
During the synthesis of the derivatives of styryl ketonic Mannich bases, a side -product IM,other than the normal Mannich base MA, is obtained. Mannich reaction is further studied and the formation mechanism of produc...During the synthesis of the derivatives of styryl ketonic Mannich bases, a side -product IM,other than the normal Mannich base MA, is obtained. Mannich reaction is further studied and the formation mechanism of product IM is postulated and discussed on the basis of deuterium labelling.展开更多
Novel 3-phenyl/pyridinyl-trans-2-(aryl/heteryl)vinyl-3H-quinazolin-4-ones 3a,b, 4a, 5a, 7a and their 6,7-difluoro de- rivatives 3c,d, 4b, 5b, 7b have been obtained by condensation of the correspondent 2-methylquinazol...Novel 3-phenyl/pyridinyl-trans-2-(aryl/heteryl)vinyl-3H-quinazolin-4-ones 3a,b, 4a, 5a, 7a and their 6,7-difluoro de- rivatives 3c,d, 4b, 5b, 7b have been obtained by condensation of the correspondent 2-methylquinazolin-4-ones 1, 6 with aromatic (heterocyclic) aldehydes in the presence of ZnCl2 (AcONa) or by the reaction of 2-methyl-3,1-benzoxazin-4- ones 2 with the Shiff bases. Effects of aryl(heteryl) substituents on photophysical properties of (aryl/heteryl) quinazolinylethenes have been studied.展开更多
Cytotoxic styryl lactone, ( + )-7-epi-Goniofufurone (1), has been prepared with a new route from 3-O-benzyl-1, 2-O-isopropylidene-5-C-phenyl-β-L-ido-pentofuranose (6), a derivative of (+)-glucose. Treatment of 14 wit...Cytotoxic styryl lactone, ( + )-7-epi-Goniofufurone (1), has been prepared with a new route from 3-O-benzyl-1, 2-O-isopropylidene-5-C-phenyl-β-L-ido-pentofuranose (6), a derivative of (+)-glucose. Treatment of 14 with HCl solution cleaved TBDMS and isopropylidene and simultaneously caused ring closure to afford 1 while treatment of 14 with Sc(OTf)3 only removed TBDMS to give 15.展开更多
Two Crown ether benzotellurastyryl cyanines and three crown ether benzotelluramerocyanines are synthesized via the key intermediate 3 methyl 5,6(15 crown 5) 2(β acetanilide)vinyl benzotellurazolium iodide.The ...Two Crown ether benzotellurastyryl cyanines and three crown ether benzotelluramerocyanines are synthesized via the key intermediate 3 methyl 5,6(15 crown 5) 2(β acetanilide)vinyl benzotellurazolium iodide.The reactive conditions are discussed.The influence of alkali( earth)metal ions on the visible absorption spectra of these two types of crown ether cyanines are also studied.展开更多
A styryl phosphonate ester(SPE) collector was used to improve the flotation performance of ilmenite, and the adsorption mechanism and model were revealed and established, respectively. Microflotation tests showed that...A styryl phosphonate ester(SPE) collector was used to improve the flotation performance of ilmenite, and the adsorption mechanism and model were revealed and established, respectively. Microflotation tests showed that SPE exhibited a stronger collecting ability for ilmenite than the traditional collector styrene phosphonic acid(SPA). Zeta potential measurements revealed that both SPE and SPA could negatively shift the zeta potential of ilmenite, while SPE had more effects than SPA, suggesting the stronger adsorption of SPE. The analysis of X-ray photoelectron spectroscopy confirmed the chemisorption of SPA and SPE onto the Fe/Ti sites of ilmenite. According to frontier orbital theory, the chemical activities of SPE are greater than those of SPA. The partial densities of states analysis indicated that the PO—H groups of the collectors could interact with the Ti/Fe atoms of the ilmenite surface to generate a stable four-membered ring. The bonding model of the collector and(104) ilmenite surface showed that the adsorption energy of SPE was higher than that of SPA. Overall, SPE presented a better collecting ability and interaction effect for ilmenite flotation than SPA, and had the potential to replace SPA in the industry.展开更多
基金Projects(51474254,51774332,51320105006) supported by the National Natural Science Foundation of ChinaProject(NCET-13-0595) supported by the Program for New Century Excellent Talents in University,ChinaProjects(2017zzts579,2017zzts379) supported by the Fundamental Research Funds for the Central Universities of China
文摘The hydrophobic flocculation flotation of rutile fines in the presence of styryl phosphonic acid（SPA） was investigated by flotation tests, zeta-potential measurement, optical microscope observation, laser-based particle size analysis, adsorption measurements and DLVO theory. The flotation tests indicated that rutile fines could be flocculated by SPA, and pH, shear force（stirring speed） and stirring time played significant roles in flocculation. The isoelectric point（IEP） and zeta-potential in whole range all moved to negative values as SPA was added according to the results from zeta-potential measurement. It was demonstrated that the primary reason for above was chemical adsorption. The laser-based particle size results showed the particle size at a stirring speed of 1800 r/min and 1000 mg/L SPA was the largest in all experiments. Furthermore, using the optical microscope observation and flotation tests, it was important for flotation of rutile fines to produce the flocculant. In the light of above-mentioned facts, floc flotation of rutile fines could be induced in the form of chemical adsorption by SPA to increase particle size. The data calculated from DLVO theory also indicated that chemical adsorption was the main reason for the formation of flocculant.
基金supported by the National Natural Science Foundation of China (Nos. 20734002, 51103163,51003106 and 51003105)Chinese Academy of Sciences (Directional key project on high performance polypropylene alloy resin development)
文摘In this paper, we review our recent progress in the synthesis and application of styryl-capped polypropylene （PP-t- St）, an excellent reactive polyolefin that is both convenient and efficient in synthesis and facile and versatile in application for preparing advanced polypropylene materials via macromolecular engineering. The synthesis of PP-t-St is made possible by a unique chain transfer reaction coordinated by a bis-styrenic molecule, such as 1,4-divinylbenzene （DVB） and 1,2-bis（4- vinylphenyl）ethane （BVPE）, and hydrogen in typical C2-symmetric metallocene （e.g. rac-Me2Si（2-Me-4-Ph-Ind）2ZrC12, in association with methylaluminocene, MAO） catalyzed propylene polymerization. The regio-selective 2,1- insertion of the styrenic double bond in DVB or BVPE into the overwhelmingly 1,2-fashioned Zr-PP propagating chain enables substantial dormancy of the catalyst active site, which triggers selective hydrogen chain transfer that, with the formed Zr-H species ultimately saturated by the insertion of propylene monomer, results in an exclusive capping of the afforded PP chains by styryl group at the termination end. With a highly reactive styryl group at chain end, PP-t-St has been used as a facile building block in PP macromolecular engineering together with the employment of state-of-the-art synthetic polymer chemistry to fabricate broad types of new polypropylene architectures.
基金National High Technology Research and Development Program of China(863 Program,2013AA064102)Hunan Provincial Science and Technology Plan Project,China (2016TP1007)。
文摘Herein,styryl phosphonate monoester(SPE) was synthesized and first introduced as rare earth extractant.The solvent extraction of lanthanum(Ⅲ) from nitrate solution using styryl phosphonate mono-isooctyl ester(SPE108),di-2-ethylhexyl phosphoric acid(D2 EHPA) and 2-ethylhexyl phosphonic acidmono-2-ethylhexyl ester(EHEHPA) as extractants was investigated.The effects of experimental parameters including equilibrium time,extractant concentration,aqueous pH,phase ratio and salt concentration on the extraction process were studied.The results indicate that the extraction ability and capacity of the extractants follow the order:SPE108> D2 EHPA> EHEHPA.What’s more,the extraction process is less affected by ammonium sulfate in the aqueous phase with SPE108.The results of the separation between lanthanum and adjacent lanthanides(Ce,Pr,Nd,Sm) show that SPE108 can separate lanthanides efficiently at low pH.The extraction mechanism of SPE108 is proved to be similar to D2 EHPA,and the density functional theory(DFT) calculation results infer that SPE108 exhibits superior extraction ability due to its strong electron-accepting ability.
基金Financial support from the National Key R&D Program of China(grant no.2019YFA09006600)the National Natural Science Foundation of China(grant nos.21977048 and 92053111)+2 种基金the Natural Science Foundation of Jiangsu Province(grant no.BK20202004)the Beijing National Laboratory for Molecular Sciences(grant no.BNLMS20200)the Jiangsu Specially-Appointed Professor Plan,and the Program for Innovative Talents and Entrepreneur in Jiangsu is gratefully acknowledged.Q.Z.is the Connie and Bob Lurie Fellow of the Damon Runyon Cancer Research Foundation(DRG-2434-21).
文摘Cysteine(Cys)-specific bioconjugation has widespread applications in the synthesis of protein conjugates,particularly for the functionalization of antibodies.Here,we report the discovery of transstyryl sulfonyl fluoride(SSF)as a near-perfect Michael acceptor for Cys-specific protein bioconjugation.Compared to maleimides,which are predominantly used,SSF exhibited better chemoselectivity,selfstability,and conjugate stability while maintaining comparable reactivity.Using SSF-derived probes,proteins can be readily modified on the Cys residue(s)to install functionalities,for example,fluorescent dyes,toxins,and oligonucleotides,without influencing the activity.Further applications of SSF-derived serum-stable antibody-drug conjugates and PD-L1 nanobody-oligo conjugates demonstrate the great translational value of SSF-based bioconjugation in drug development and single-cell sequencing.
文摘The reactions of 2-methylbenzimidazole or 2-methylbenzimidazolium iodide with aromatic aldehydes are accelerated under microwave irradiation by using Ac2O or piperidine as dehydrant or catalyst in the absence of any solvent. The approach provides an attractive and environmentally friendly pathway to several useful styryl dyes with benzimidazole nucleus.
文摘The Palladium inserted hydridopalladium species represents as RCOOPdH. This work finds an interesting coupling of palladium inserted RCOOPdH species with potassium styryltrifluoroborates to synthesize new kinds of styryl ester compounds. Pd(OAc)<sub>2</sub> was most effective catalyst for this new cross-coupling reaction under microwave irradiation and gave styryl esters in good to moderate yields.
基金Supported by the National Natural Science Foundation of China(Nos.5 9872 0 0 12 0 0 2 30 0 5 ) and the State Key Projectfor Fundamental Research(No.G19980 6 130 8) .
文摘An amphiphilic benziminazole styryl dye, 2 (4 dihexadecylaminostyryl)benziminazolium TCNQ -(DBTCNQ), was synthesized and successfully transferred onto the substrates by Langmuir Blodgett(LB) technique. H aggregates were formed on the substrates. Its monolayer second order susceptibility[ χ (2) zzz = 109 p/mV) was determined with a polarized laser beam(Nd∶YAG, λ =1.064 μm). The photoelectrochemistry of the dye LB monolayer films was investigated in a traditional three electrode cell. The quantum efficiency of photoelectric conversion is 1.08% under favorable conditions [-200 mV, 0.5 mg/mL methylviologen diiodide(MV 2+ ) in 0.5 mol/L KCl electrolyte solution]. The experimental data indicate that the LB film exhibits multifunctional properties.
基金the National Natural Science Foundation of China.
文摘During the synthesis of the derivatives of styryl ketonic Mannich bases, a side -product IM,other than the normal Mannich base MA, is obtained. Mannich reaction is further studied and the formation mechanism of product IM is postulated and discussed on the basis of deuterium labelling.
文摘Novel 3-phenyl/pyridinyl-trans-2-(aryl/heteryl)vinyl-3H-quinazolin-4-ones 3a,b, 4a, 5a, 7a and their 6,7-difluoro de- rivatives 3c,d, 4b, 5b, 7b have been obtained by condensation of the correspondent 2-methylquinazolin-4-ones 1, 6 with aromatic (heterocyclic) aldehydes in the presence of ZnCl2 (AcONa) or by the reaction of 2-methyl-3,1-benzoxazin-4- ones 2 with the Shiff bases. Effects of aryl(heteryl) substituents on photophysical properties of (aryl/heteryl) quinazolinylethenes have been studied.
文摘Cytotoxic styryl lactone, ( + )-7-epi-Goniofufurone (1), has been prepared with a new route from 3-O-benzyl-1, 2-O-isopropylidene-5-C-phenyl-β-L-ido-pentofuranose (6), a derivative of (+)-glucose. Treatment of 14 with HCl solution cleaved TBDMS and isopropylidene and simultaneously caused ring closure to afford 1 while treatment of 14 with Sc(OTf)3 only removed TBDMS to give 15.
文摘Two Crown ether benzotellurastyryl cyanines and three crown ether benzotelluramerocyanines are synthesized via the key intermediate 3 methyl 5,6(15 crown 5) 2(β acetanilide)vinyl benzotellurazolium iodide.The reactive conditions are discussed.The influence of alkali( earth)metal ions on the visible absorption spectra of these two types of crown ether cyanines are also studied.
基金the support from the National Natural Science Foundation of China(Nos.51904214 and 51804238)the Young Elite Scientists Sponsorship Program by CAST(No.YESS20200276)+3 种基金the Natural Science Foundation of Hubei Province,China(No.ZRMS2021000085)the Fundamental Research Funds for the Central Universities,China(No.2021IVA039)the Open Foundation of State Key Laboratory of Mineral Processing,BGRIMM Technology,China(Nos.BGRIMM-KJSKL-202122 and BGRIMM-KJSKL-2022-02)the Open Project of Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education,China(No.201904)。
文摘A styryl phosphonate ester(SPE) collector was used to improve the flotation performance of ilmenite, and the adsorption mechanism and model were revealed and established, respectively. Microflotation tests showed that SPE exhibited a stronger collecting ability for ilmenite than the traditional collector styrene phosphonic acid(SPA). Zeta potential measurements revealed that both SPE and SPA could negatively shift the zeta potential of ilmenite, while SPE had more effects than SPA, suggesting the stronger adsorption of SPE. The analysis of X-ray photoelectron spectroscopy confirmed the chemisorption of SPA and SPE onto the Fe/Ti sites of ilmenite. According to frontier orbital theory, the chemical activities of SPE are greater than those of SPA. The partial densities of states analysis indicated that the PO—H groups of the collectors could interact with the Ti/Fe atoms of the ilmenite surface to generate a stable four-membered ring. The bonding model of the collector and(104) ilmenite surface showed that the adsorption energy of SPE was higher than that of SPA. Overall, SPE presented a better collecting ability and interaction effect for ilmenite flotation than SPA, and had the potential to replace SPA in the industry.
