The graft copolymerization of acrylic acid（AA） onto polyethylene glycol terephthalate（PET） fiber initiated by benzoy peroxide （BPO） was carried out in heterogeneous media.Moreover,modification of the grafted PET...The graft copolymerization of acrylic acid（AA） onto polyethylene glycol terephthalate（PET） fiber initiated by benzoy peroxide （BPO） was carried out in heterogeneous media.Moreover,modification of the grafted PET fiber（PET-AA） was done by changing the carboxyl group into acylamino and amino groups through the reaction with ethylenediamine.The new modified chelating fiber （NDWJN6） was characterized using elementary analysis,SEM and FT-IR spectroscopy.Adsorption kinetic curve indicated that NDWJN6 could fastly remove Pb^（2＋） from water,and adsorption isotherm also indicated that NDWJN6 had high equilibrium adsorption capacity for Pb^（2＋）.展开更多
Activated carbons were prepared by two chemical methods and the adsorption of Cu(II) on activated carbons from aqueous solution containing amino groups was studied. The first method involved the chlorination of activa...Activated carbons were prepared by two chemical methods and the adsorption of Cu(II) on activated carbons from aqueous solution containing amino groups was studied. The first method involved the chlorination of activated carbon following by substitution of chloride groups with amino groups, and the second involved the nitrilation of activated carbon with reduction of nitro groups to amino groups. Resultant activated carbons were characterized in terms of porous structure, elemental analysis, FTIR spectroscopy, XPS, Boehm titration,and p Hzpc. Kinetic and equilibrium tests were performed for copper adsorption in the batch mode. Also,adsorption mechanism and effect of p H on the adsorption of Cu(II) ions were discussed. Adsorption study shows enhanced adsorption for copper on the modified activated carbons, mainly by the presence of amino groups, and the Freundlich model is applicable for the activated carbons. It is suggested that binding of nitrogen atoms with Cu(II) ions is stronger than that with H+ions due to relatively higher divalent charge or stronger electrostatic force.展开更多
Abstract A novel polyglycidylmethacrylate （PGMA） microspheres with high adsorption capacity of Cr（VI） was prepared by cerium（IV） initiated graft polymerization of tentacle-type polymer chains with amino group on...Abstract A novel polyglycidylmethacrylate （PGMA） microspheres with high adsorption capacity of Cr（VI） was prepared by cerium（IV） initiated graft polymerization of tentacle-type polymer chains with amino group on polymer microspheres with hydroxyl groups. The micron-sized PGMA microspheres were prepared by a dispersion polym erization method and subsequently modified by ring-opening reaction to introduce functional hydroxyl groups. The polymer microspheres were characterized by scanning electron microscopy （SEM） and Fourier transform infrared spectroscopy （FTIR）. The results indicated that the polymer microspheres had an average diameter of 5 m with uniform size distribution. The free amino group content was determined to be 5.13 mmol·g^-1 for g;PGMA-NH2 microspheres by potentiometric and conductometric titration methods. The Cr（VI） adsorption results indicated that the graft polymerization of tentacle-type polymer chains on the polymer microspheres could produce adsorbents with high adsorption capacity （500 mg-g-l）. The polymer microspheres with grafted tentacle polymer chains have potenial application in large-scale removal of Cr（VI） in aqueous solution.展开更多
As a small catalytic DNA molecule, 10-23 DNAzyme has cleavage ability against complementary RNA. Previous studies of chemical modification have shown that its catalytic core can be further optimized in order to obtain...As a small catalytic DNA molecule, 10-23 DNAzyme has cleavage ability against complementary RNA. Previous studies of chemical modification have shown that its catalytic core can be further optimized in order to obtain more powerful catalytic ability. The analogues of 2＇-deoxyadenosine （5） and 2＇-deoxyguanosine （6） could improve the cleavage ability of the DNAzyme when positioned at positions A9, （32 and G14 in the catalytic core, respectively. Moreover, their combinatorial incorporations were studied, the results implicated that the effect was position-dependent, and positive additive results could be achieved at some positions. The highly conserved G1, G2 and G14 could be optimized by single or combinatorial modification with 2＇-deoxyguanosine analogues. Chemical modifications on the functional groups of the core residues would be a feasible approach for the optimization of 10-23 DNAzyme.展开更多
Solar-driven CO_(2)conversion and pollutant removal with an S-scheme heterojunction provides promising approach to alleviate energy shortage and environmental crisis,yet the comprehensive regulation of the charge sepa...Solar-driven CO_(2)conversion and pollutant removal with an S-scheme heterojunction provides promising approach to alleviate energy shortage and environmental crisis,yet the comprehensive regulation of the charge separation and the activation sites of reactant molecules remains challenging.Herein,a dual-active groups regulated S-scheme heterojunction for hydroxy-regulated BiOBr modified amino-functionalized g-C_(3)N_(4)(labeled as HBOB/ACN)was designed by spatially separated dual sites with hydroxyl group(OH)and amino group(NH_(2))toward simultaneously photocatalytic CO_(2)reduction and ciprofloxacin(CIP)oxidation.The optimized HBOB/ACN delivers around 2.74-fold CO yield rate and 1.61-times CIP removal rate in comparison to BiOBr/g-C_(3)N_(4)(BOB/CN)without surface groups,which chiefly ascribed the synergistic effect of OH and NH_(2)group.A series of experiments and theoretical calculation unveiled that the OH and NH_(2)group trapped holes and electrons to participate in CIP oxidation and CO_(2)reduction,respectively.Besides,dual-functional coupled reaction system realized the complete utilization of carriers.This work affords deep insights for dual-group modified S-scheme heterojunctions with redox active sites toward dual-functional coupled reaction system for environment purification and solar fuel production.展开更多
In order to study the influences of functionalized groups onto the adsorption of tetracycline,we prepared a series of amino and amino–Fe^（3＋）complex mesoporous silica adsorbents with diverse content of amino and ...In order to study the influences of functionalized groups onto the adsorption of tetracycline,we prepared a series of amino and amino–Fe^（3＋）complex mesoporous silica adsorbents with diverse content of amino and Fe^（3＋）groups（named N,N-SBA15 and Fe-N,N-SBA15）.The resulting mesoporous silica adsorbents were fully characterized by X-ray powder diffraction（XRD）,Fourier transform infrared spectrometer（FTIR）and N2adsorption/desorption isotherms.Furthermore,the effects of functionalized groups on the removal of TC were investigated.The results showed that the periodic ordered structure of SBA-15 was maintained after modification of amino/Fe^（3＋）groups.The functionalized amino groups decreased the adsorption capacity while the coordinated Fe^（3＋）increased the adsorption capacity.The adsorption kinetics of TC fitted pseudo-second-order model well and the equilibrium was achieved quickly.The adsorption isotherms fitted the Langmuir model well and with the Fe^（3＋）content increased from 3.93%to 8.26%,the Q（max）of the adsorbents increased from 102 to 188 mmol/kg.The solution p H affected the adsorption of TC onto amino complex adsorbents slightly while influenced the adsorption onto Fe-amine complex adsorbents greatly.The adsorption of TC on SBA15 and N,N-SBA15 may be related to the formation of outer-sphere surface complexes,while the adsorption of TC onto Fe-N,N-SBA15 was mainly attributed to the inner-sphere surface complexes.This study could offer potential materials that have excellent adsorption behavior for environmental remediation and suggested useful information for the preparing other adsorbents in environmental applications.展开更多
Mesoporous silicas have a very attractive ability of sorption and enrichment of metal ions due to their huge surface area and facile functionalization by organic ligands. In this work, phosphonate-amino hifunctionaliz...Mesoporous silicas have a very attractive ability of sorption and enrichment of metal ions due to their huge surface area and facile functionalization by organic ligands. In this work, phosphonate-amino hifunctionalized mesoporous silica SBA-15 （PA-SBA-15） as U（VI） sorbent was fabricated through post-grafting method. The obtained mesoporous silica was character- ized by SEM, XRD, NMR and nitrogen sorption/desorption experiments, which revealed the existence of ordered mesoporous structure with uniform pore diameter and large surface area. The adsorptivity of PA-SBA-15 for U（VI） from aqueous solution was investigated using batch sorption technique under different experimental conditions. The preliminary results show that the U（VI） sorption by PA-SBA-15 is very quick with equilibrium time of less than 1 h, and the U（VI） uptake is as large as 373 mg/g at pH 5.5 under 95℃. The sorption isotherm has been successfully modeled by the Langmuir isotherm, suggesting a monolayer homogeneous sorption of U（VI） in PA-SBA-15. The sorption is pH-dependent due to the pH-dependent charge of sorbent in the aqueous solution. The thermodynamics research shows that the sorption is a feasible and endothermic process. Based on these results, PA-SBA-15 could be a promising solid phase sorbent for highly-efficient removal of U（VI） ions from waste water and enrichment of U（VI） from a solution at a very low level.展开更多
In this study,TiO_(2)functionalized with organic groups were prepared to study the effect of carboxyl and amino groups on the adsorption behavior of TiO_(2)for the removal of acid red G(ARG)as an anionic dye from aque...In this study,TiO_(2)functionalized with organic groups were prepared to study the effect of carboxyl and amino groups on the adsorption behavior of TiO_(2)for the removal of acid red G(ARG)as an anionic dye from aqueous solution.TiO_(2)was successfully modified with carboxyl and amino groups by using the hydrolysis method with oxalic acid(OAD,with two carboxyl groups),ethylenediamine(EDA,with two amino groups)and DL-alanine(DLA,with one carboxyl group and one amino group)at low temperature(65℃)and labeled as OAD-TiO_(2),EDA-TiO_(2)and DLA-TiO_(2),respectively.The ARG uptake by the functionalized TiO_(2)samples was largely dependent on the functional groups.The interaction between ARG and the functional organic groups on the TiO_(2)samples plays an important role in the adsorption process,which leads to the excellent adsorption performance(higher capacity and faster adsorption rate)of the functionalized TiO_(2)samples than that of P25(commercial TiO_(2)without modification).Furthermore,there is no obvious loss of the adsorption capacity for the functionalized TiO_(2)even after 5 adsorption-desorption cycles,which indicated the good reusability of the modified TiO_(2)samples for anionic dye removal from aqueous solution.展开更多
Amino group protective strategy has consequently emerged in multistep organic synthesis.Easy and selective deprotection procedures are crucial to facilitate the chemical transformation.Recently,Zhang’s group from Hen...Amino group protective strategy has consequently emerged in multistep organic synthesis.Easy and selective deprotection procedures are crucial to facilitate the chemical transformation.Recently,Zhang’s group from Henan Normal University collaborating with Chen’s group of Nankai University developed a novel strategy for the regiospecific cleavage of inert aryl C-N bonds in N-aryl amides by hypervalent iodine(V)reagents.These procedures allow removal of sort of aryl groups under mild conditions to give primary amides in high efficiency.It bestows these aryl groups with the characteristics of amino protecting groups that might be the supplement of amino protecting group chemistry.展开更多
Novel amino （-NH2） functionalized mesoporous polyvinyl pyrrolidone （PVP）/SiO2 composite nanofiber membranes were fabricated by a one-step electrospinning method using poly （vinyl alcohol） and tetraethyl orthosil...Novel amino （-NH2） functionalized mesoporous polyvinyl pyrrolidone （PVP）/SiO2 composite nanofiber membranes were fabricated by a one-step electrospinning method using poly （vinyl alcohol） and tetraethyl orthosilicate （TEOS） mixed with cationic surfactant, cety｜trimethyl ammonium bromide （CTAB） as the structure directing agent. Ureidopropyltriethoxysilane was used for functionalization of the internal pore surfaces. The membranes were characterized by scanning electron microscopy （SEM）, high-resolution transmission electron microscopy （HRTEM） images, X-ray diffraction （XRD）, Fourier-transform infrared spectroscopy （FT-IR）, element analyzer and Nz adsorption-desorption isotherms, The nanofiber diameters, average pore diameters and surface areas were 100-700 nm, 2.86 nm and 873,62 m2/g, respectively. These mesoporous membranes functionalized with -NH2 groups exhibited very high adsorptions properties based on the adsorption of Cr3＋ from an aqueous solution. Equilibrium adsorption was achieved after approximately 20 rain and more than 97% of chronium ions in the solution were removed. The membrane could be regenerated through acidification.展开更多
Monodispersed poly（glycidyl methacrylate）（PGMA） microspheres with various amounts of amino groups（PGMA-NH2） were used to adsorb Au（Ⅲ） from simulated wastewaters. Gold nanoparticle-coated PGMA functional micro...Monodispersed poly（glycidyl methacrylate）（PGMA） microspheres with various amounts of amino groups（PGMA-NH2） were used to adsorb Au（Ⅲ） from simulated wastewaters. Gold nanoparticle-coated PGMA functional microspheres can be directly obtained via the adsorption process. The adsorption kinetics follows pseudo-second model, and 10 min is enough for reaching at equilibrium. The adsorption isotherm follows Langmuir model, and the adsorption amounts for Au（Ⅲ） are 8.25 and 21.75 mol·kg^-1 at 298 and 328 K, respectively. The relative separation coefficients between Au（Ⅲ）, Pt（Ⅵ）, Pd（Ⅱ）and Co（Ⅱ）, Cu（Ⅱ）; Ni（Ⅱ）, Fe（Ⅲ） are all higher than 100 when 1 〈 pH 〈 3. Furthermore, the characterization analysis of X-ray diffraction（XRD）, thermogravimetrydifferential scanning calorimetry（TG-DSC）, scanning electron microscopy-energy dispersive spectroscopy（SEM-EDS）, transmission electron microscopy（TEM） and Fourier transform infrared spectroscopy（FTIR） confirms that AuCl4^-has been reduced to Au^0 nanoparticles and deposited onto the surface of PGMA-NH2. The current work shows a good prospect for PGMA-NH2 to be a valid adsorbent for the recovery of gold and the possible fabrication of gold nanoparticles by reduction-deposition process without any reductant.展开更多
A novel phthalonitrile derivative containing an amino group, 3,5-bis（3,4-dicyanophenoxy）aniline （CPA）, was synthesized via a nucleophilic displacement of 4-nitrophthalonitrile and 5-aminoresorcinol hydrochloride. ...A novel phthalonitrile derivative containing an amino group, 3,5-bis（3,4-dicyanophenoxy）aniline （CPA）, was synthesized via a nucleophilic displacement of 4-nitrophthalonitrile and 5-aminoresorcinol hydrochloride. The structure of CPA was confirmed by Fourier transform infrared spectra （FT-IR） and nuclear magnetic resonance （^1H NMR）. Thermal analysis performed on CPA revealed that the novel phthalonitrile derivative showed a self-promotion curing behavior and the resulting polymer exhibited outstanding heat-resistance.展开更多
Poly（phenylene ethynylene）s （P1） with 4-vinylaniline pendant groups were successfully prepared by the Sonogashira coupling polymerization bevween 1,4-diethynyl-2,5-bis（pentyloxy）benzene and 4-[2-（2,5-dibromophe...Poly（phenylene ethynylene）s （P1） with 4-vinylaniline pendant groups were successfully prepared by the Sonogashira coupling polymerization bevween 1,4-diethynyl-2,5-bis（pentyloxy）benzene and 4-[2-（2,5-dibromophenyl）vinyl]- aniline. In comparison with its analogue P2 without amino group, the emission of F＇I is only enihanced by aggregation when adding n-hexane into its THF solution, exhibiting an aggregation-induced emission enhancement （AIEE） effect. When methanol or water instead of hexane was added into THF solution, P1, however, didn＇t show AII：~E. The results indicated that amino groups strengthen the inter-chain and intra-chain interactions in P1 and restrict the no^-radiative energy transition. This strategy can provide a platform for developing highly sensitive and efficient bio- and chemosensors.展开更多
Buxrugulosides A–E,four lignan glycosides(1–4)and a protocatechuate derivative(5)featuring a rare(N,Ndiethyl)methyl amino group at aromatic rings,were obtained from the aerial parts of Buxus rugulosa,which is famous...Buxrugulosides A–E,four lignan glycosides(1–4)and a protocatechuate derivative(5)featuring a rare(N,Ndiethyl)methyl amino group at aromatic rings,were obtained from the aerial parts of Buxus rugulosa,which is famous for treating coronary heart disease.Their structures including absolute configurations were elucidated by HRMS,1 D and 2 D NMR,and by comparing their CD data with previous reports.Compound 1 was a rare sesquilignan,and all of these compounds were the first example of lignans with(N,N-diethyl)methyl amino group.展开更多
A novel D-π-A type α-cyanostilbenzene derivative,（Z）-2-（4-aminophenyl）-3-（4-bromophenyl）-acrylonitrile（ABAN）, was designed and synthesized, by introducing an electrondonating amino group and a heavy atom. Th...A novel D-π-A type α-cyanostilbenzene derivative,（Z）-2-（4-aminophenyl）-3-（4-bromophenyl）-acrylonitrile（ABAN）, was designed and synthesized, by introducing an electrondonating amino group and a heavy atom. The structure of ABAN was confirmed by FT-IR, 1H NMR, 13 C NMR spectra and single-crystal X-ray diffraction analysis. The ABAN is of orthorhombic system, space group P212121, with a = 8.6100（14）, b = 9.6923（16）, c = 15.705（3） , Mr = 299.17, V = 1310.6（4） 3, Z = 4, Dc = 1.516 g/cm-3, μ = 3.119 mm-1, F（000） = 600, Rint = 0.038, R（I 〉 2σ（I）） = 0.0276, w R（I 〉 2σ（I）） = 0.0628, R（all data） = 0.0324, wR（all data） = 0.0646, completeness to theta = 25.00 was 99.8% and GOOF = 1.04. In the crystal structure, ABAN molecules were linked with each other through intermolecular C–H···π interactions and N–H···N hydrogen bonds, by which the 1D chain, 2D plane and 3D stacking structures were constructed. The photophysical properties and calculation results confirmed that ABAN possessed an intramolecular charge transfer（ICT） process. ABAN could be applied into the optoelectronic material field due to good solvent-tuned photophysical properties and highly thermal stability.展开更多
Effective CO_(2) adsorption and fast electron injection are two crucial processes of photocatalysts for achieving high-efficiency CO_(2) photo-reduction.However,simultaneously enhancing these processes within a single...Effective CO_(2) adsorption and fast electron injection are two crucial processes of photocatalysts for achieving high-efficiency CO_(2) photo-reduction.However,simultaneously enhancing these processes within a single photocatalyst remains a challenging task.Herein,we propose an intriguing edge effect based on the intrinsic atomic structure of g-C_(3)N_(4) nanosheets(NSs)to enhance their CO_(2) adsorption and facilitate the transfer of photo-generated electrons to the adsorbed CO_(2).By cutting large pieces of g-C_(3)N_(4) NSs into smaller fragments,the exposure of amino groups at the edges of its repeating tri-s-triazine units can be significantly increased.These edge-exposed amino groups serve as active sites for enhancing the CO_(2) capture capacity of g-C_(3)N_(4) NSs.As we decrease the lateral size of g-C_(3)N_(4) NSs from tens of micrometers to hundreds of nanometers,their CO_(2) adsorption capacity increases from 4.74 to 8.56 cm^(3) g^(-1).Reducing the size of g-C_(3)N_(4) NSs also facilitates the transfer of photo-generated electrons to the edge-adsorbed CO_(2).Thus,our optimized g-C_(3)N_(4) NSs with the edge effect exhibits a 37-fold enhancement in activity for CO_(2) photo-reduction compared to normal g-C_(3)N_(4) NSs under simulated sunlight irradiation.Notably,by introducing Pt cocatalysts,we can control product selectivity from 85.9%CO to 97.9%CH_(4).展开更多
Two novel polymers （NJ-1 and N J-2） were synthesized by chemically modified a hypercrosslinked polymer NJ-0 with dimethylamine and trimethylamine, respectively. The comparison of the adsorption properties of the thr...Two novel polymers （NJ-1 and N J-2） were synthesized by chemically modified a hypercrosslinked polymer NJ-0 with dimethylamine and trimethylamine, respectively. The comparison of the adsorption properties of the three polymers toward phenol, resorcin and phloroglucin was made. The study focused on the static equilibrium adsorption behaviors and the adsorption thermodynamics. Freundlich equation was found to fit the adsorption results well. The effect of amino groups introduced onto the surface of the resin and the structure of phenolic compounds on the adsorption were also studied. The hydrogen-bonding interaction and electrostatic interaction could happen between the amino groups and the adsorbates. The adsorption impetus increased as quantity of hydroxyl groups increased, but the adsorption capacity decreased due to the drop of the matching degree of the aperture of resins and the diameter of adsorbate molecules.展开更多
Bearing unique redox nature and high oxygen storage capacity,ceria(CeO_(2))has always been a promising CO oxidation catalyst support for gold(Au)catalysts and the like.Herein,a series of Au-CeO_(2)-P(P stands for pH v...Bearing unique redox nature and high oxygen storage capacity,ceria(CeO_(2))has always been a promising CO oxidation catalyst support for gold(Au)catalysts and the like.Herein,a series of Au-CeO_(2)-P(P stands for pH value)samples was prepared by a co-precipitation method with the assistance of an alkaline environment and amino groups functionalized ordered mesoporous polymer(OMP-NH_(2)).Afterward,all samples described above were characterized that the Au-CeO_(2)-P catalysts are made of Au-Ce-O solid solution and Au nanoparticles(NPs)supported on CeO_(2).It turns out that OMP-NH_(2) is not just a simple sacrificial template for mesoporous structure,but also plays an important role as an amino source,explaining the presence of rich oxygen vacancies.Due to the concentration of oxygen vacancies in Au-Ce-O solid solution is the key factor for the oxygen mobility of CO oxidation,the catalytic results also demonstrate that the catalytic activity of Au-CeO_(2)-P catalysts is related to the concentration of their oxygen vacancies.Moreover,Au-CeO_(2)-9.6 with a highest concentration of oxygen vacancies(as high as 13.98%)in Au-CeO_(2)-P catalysts exhibits the best catalytic activity(complete conversion at 10℃).展开更多
Until now, automation in nanomaterial research has been largely focused on the automated synthesis of engineered nanoparticles (NPs) including the screening of synthesis parameters and the automation of characterizati...Until now, automation in nanomaterial research has been largely focused on the automated synthesis of engineered nanoparticles (NPs) including the screening of synthesis parameters and the automation of characterization methods such as electron microscopy. Despite the rapidly increasing number of NP samples analyzed due to increasing requirements on NP quality control, increasing safety concerns, and regulatory requirements, automation has not yet been introduced into workflows of analytical methods utilized for screening, monitoring, and quantifying functional groups (FGs) on NPs. To address this gap, we studied the potential of simple automation tools for the quantification of amino surface groups on different types of aminated NPs, varying in size, chemical composition, and optical properties, with the exemplarily chosen sensitive optical fluorescamine (Fluram) assay. This broadly applied, but reportedly error-prone assay, which utilizes a chromogenic reporter, involves multiple pipetting and dilution steps and photometric or fluorometric detection. In this study, we compared the influence of automated and manual pipetting on the results of this assay, which was automatically read out with a microplate reader. Special emphasis was dedicated to parameters like accuracy, consistency, achievable uncertainties, and speed of analysis and to possible interferences from the NPs. Our results highlight the advantages of automated surface FG quantification and the huge potential of automation for nanotechnology. In the future, this will facilitate process and quality control of NP fabrication, surface modification, and stability monitoring and help to produce large data sets for nanomaterial grouping approaches for sustainable and safe-by-design, performance, and risk assessment studies.展开更多
The magnetic poly-（methacrylate-divinyl benzene） microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr（VI） from aqueous solution by magnetic poly-（MA-DVB） ...The magnetic poly-（methacrylate-divinyl benzene） microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr（VI） from aqueous solution by magnetic poly-（MA-DVB） microspheres with surface amination was investigated. The adsorption processes were carried out under diversified conditions of pH value, adsorption time and temperature to evaluate the perlbrmance of the magnetic microspheres. The optimum pH value for Cr（VI） adsorption was found as 3. The adsorption capacity increased with adsorption time and attained an optimum at 60 rain. The adsorption processes for magnetic microspheres was endothermic reaction, and the adsorption capacity increased with increasing temperature.展开更多
基金support provided by the National Science Funds for Young Scientists(No. 51008152)the Nature Science Fund of Jiangsu Province(No.BK2010381)the Fundamental Research Funds for the Central Universities
文摘The graft copolymerization of acrylic acid（AA） onto polyethylene glycol terephthalate（PET） fiber initiated by benzoy peroxide （BPO） was carried out in heterogeneous media.Moreover,modification of the grafted PET fiber（PET-AA） was done by changing the carboxyl group into acylamino and amino groups through the reaction with ethylenediamine.The new modified chelating fiber （NDWJN6） was characterized using elementary analysis,SEM and FT-IR spectroscopy.Adsorption kinetic curve indicated that NDWJN6 could fastly remove Pb^（2＋） from water,and adsorption isotherm also indicated that NDWJN6 had high equilibrium adsorption capacity for Pb^（2＋）.
文摘Activated carbons were prepared by two chemical methods and the adsorption of Cu(II) on activated carbons from aqueous solution containing amino groups was studied. The first method involved the chlorination of activated carbon following by substitution of chloride groups with amino groups, and the second involved the nitrilation of activated carbon with reduction of nitro groups to amino groups. Resultant activated carbons were characterized in terms of porous structure, elemental analysis, FTIR spectroscopy, XPS, Boehm titration,and p Hzpc. Kinetic and equilibrium tests were performed for copper adsorption in the batch mode. Also,adsorption mechanism and effect of p H on the adsorption of Cu(II) ions were discussed. Adsorption study shows enhanced adsorption for copper on the modified activated carbons, mainly by the presence of amino groups, and the Freundlich model is applicable for the activated carbons. It is suggested that binding of nitrogen atoms with Cu(II) ions is stronger than that with H+ions due to relatively higher divalent charge or stronger electrostatic force.
基金Supported by the National Natural Science Foundation of China (21106162)the National Key Natural Science Foundation of China (21136009)+1 种基金the National High Technology Research and Development Program of China (2009CB219904)the State Key Laboratory of Chemical Engineering (SKL-ChE-11A04)
文摘Abstract A novel polyglycidylmethacrylate （PGMA） microspheres with high adsorption capacity of Cr（VI） was prepared by cerium（IV） initiated graft polymerization of tentacle-type polymer chains with amino group on polymer microspheres with hydroxyl groups. The micron-sized PGMA microspheres were prepared by a dispersion polym erization method and subsequently modified by ring-opening reaction to introduce functional hydroxyl groups. The polymer microspheres were characterized by scanning electron microscopy （SEM） and Fourier transform infrared spectroscopy （FTIR）. The results indicated that the polymer microspheres had an average diameter of 5 m with uniform size distribution. The free amino group content was determined to be 5.13 mmol·g^-1 for g;PGMA-NH2 microspheres by potentiometric and conductometric titration methods. The Cr（VI） adsorption results indicated that the graft polymerization of tentacle-type polymer chains on the polymer microspheres could produce adsorbents with high adsorption capacity （500 mg-g-l）. The polymer microspheres with grafted tentacle polymer chains have potenial application in large-scale removal of Cr（VI） in aqueous solution.
基金The National Natural Science Foundation of China(Grant No.21572268)
文摘As a small catalytic DNA molecule, 10-23 DNAzyme has cleavage ability against complementary RNA. Previous studies of chemical modification have shown that its catalytic core can be further optimized in order to obtain more powerful catalytic ability. The analogues of 2＇-deoxyadenosine （5） and 2＇-deoxyguanosine （6） could improve the cleavage ability of the DNAzyme when positioned at positions A9, （32 and G14 in the catalytic core, respectively. Moreover, their combinatorial incorporations were studied, the results implicated that the effect was position-dependent, and positive additive results could be achieved at some positions. The highly conserved G1, G2 and G14 could be optimized by single or combinatorial modification with 2＇-deoxyguanosine analogues. Chemical modifications on the functional groups of the core residues would be a feasible approach for the optimization of 10-23 DNAzyme.
文摘Solar-driven CO_(2)conversion and pollutant removal with an S-scheme heterojunction provides promising approach to alleviate energy shortage and environmental crisis,yet the comprehensive regulation of the charge separation and the activation sites of reactant molecules remains challenging.Herein,a dual-active groups regulated S-scheme heterojunction for hydroxy-regulated BiOBr modified amino-functionalized g-C_(3)N_(4)(labeled as HBOB/ACN)was designed by spatially separated dual sites with hydroxyl group(OH)and amino group(NH_(2))toward simultaneously photocatalytic CO_(2)reduction and ciprofloxacin(CIP)oxidation.The optimized HBOB/ACN delivers around 2.74-fold CO yield rate and 1.61-times CIP removal rate in comparison to BiOBr/g-C_(3)N_(4)(BOB/CN)without surface groups,which chiefly ascribed the synergistic effect of OH and NH_(2)group.A series of experiments and theoretical calculation unveiled that the OH and NH_(2)group trapped holes and electrons to participate in CIP oxidation and CO_(2)reduction,respectively.Besides,dual-functional coupled reaction system realized the complete utilization of carriers.This work affords deep insights for dual-group modified S-scheme heterojunctions with redox active sites toward dual-functional coupled reaction system for environment purification and solar fuel production.
基金supported by Beijing Postdoctoral Science Foundation (No. 21009916007)Beijing Outstanding Talent Project for Excellent Youth Team (No. 2015000026833T0000)+1 种基金the National Science Fund for Distinguished Young Scholars of China (No. 51225805)Natural Science Foundation of China (No. 51678025)
文摘In order to study the influences of functionalized groups onto the adsorption of tetracycline,we prepared a series of amino and amino–Fe^（3＋）complex mesoporous silica adsorbents with diverse content of amino and Fe^（3＋）groups（named N,N-SBA15 and Fe-N,N-SBA15）.The resulting mesoporous silica adsorbents were fully characterized by X-ray powder diffraction（XRD）,Fourier transform infrared spectrometer（FTIR）and N2adsorption/desorption isotherms.Furthermore,the effects of functionalized groups on the removal of TC were investigated.The results showed that the periodic ordered structure of SBA-15 was maintained after modification of amino/Fe^（3＋）groups.The functionalized amino groups decreased the adsorption capacity while the coordinated Fe^（3＋）increased the adsorption capacity.The adsorption kinetics of TC fitted pseudo-second-order model well and the equilibrium was achieved quickly.The adsorption isotherms fitted the Langmuir model well and with the Fe^（3＋）content increased from 3.93%to 8.26%,the Q（max）of the adsorbents increased from 102 to 188 mmol/kg.The solution p H affected the adsorption of TC onto amino complex adsorbents slightly while influenced the adsorption onto Fe-amine complex adsorbents greatly.The adsorption of TC on SBA15 and N,N-SBA15 may be related to the formation of outer-sphere surface complexes,while the adsorption of TC onto Fe-N,N-SBA15 was mainly attributed to the inner-sphere surface complexes.This study could offer potential materials that have excellent adsorption behavior for environmental remediation and suggested useful information for the preparing other adsorbents in environmental applications.
基金supported by the National Natural Science Foundation of China (91026007)the "Strategic Priority Research program" of the Chinese Academy of Sciences (XDA03010401,XDA03010403)
文摘Mesoporous silicas have a very attractive ability of sorption and enrichment of metal ions due to their huge surface area and facile functionalization by organic ligands. In this work, phosphonate-amino hifunctionalized mesoporous silica SBA-15 （PA-SBA-15） as U（VI） sorbent was fabricated through post-grafting method. The obtained mesoporous silica was character- ized by SEM, XRD, NMR and nitrogen sorption/desorption experiments, which revealed the existence of ordered mesoporous structure with uniform pore diameter and large surface area. The adsorptivity of PA-SBA-15 for U（VI） from aqueous solution was investigated using batch sorption technique under different experimental conditions. The preliminary results show that the U（VI） sorption by PA-SBA-15 is very quick with equilibrium time of less than 1 h, and the U（VI） uptake is as large as 373 mg/g at pH 5.5 under 95℃. The sorption isotherm has been successfully modeled by the Langmuir isotherm, suggesting a monolayer homogeneous sorption of U（VI） in PA-SBA-15. The sorption is pH-dependent due to the pH-dependent charge of sorbent in the aqueous solution. The thermodynamics research shows that the sorption is a feasible and endothermic process. Based on these results, PA-SBA-15 could be a promising solid phase sorbent for highly-efficient removal of U（VI） ions from waste water and enrichment of U（VI） from a solution at a very low level.
基金the Shaanxi Key research and development projects,China(Grant No.2017SF-386)the Fundamental Research Funds for the Central Universities of China and the Key Industrial Project in Xianyang City,Shaanxi,China(Grant No.2018k02-10).
文摘In this study,TiO_(2)functionalized with organic groups were prepared to study the effect of carboxyl and amino groups on the adsorption behavior of TiO_(2)for the removal of acid red G(ARG)as an anionic dye from aqueous solution.TiO_(2)was successfully modified with carboxyl and amino groups by using the hydrolysis method with oxalic acid(OAD,with two carboxyl groups),ethylenediamine(EDA,with two amino groups)and DL-alanine(DLA,with one carboxyl group and one amino group)at low temperature(65℃)and labeled as OAD-TiO_(2),EDA-TiO_(2)and DLA-TiO_(2),respectively.The ARG uptake by the functionalized TiO_(2)samples was largely dependent on the functional groups.The interaction between ARG and the functional organic groups on the TiO_(2)samples plays an important role in the adsorption process,which leads to the excellent adsorption performance(higher capacity and faster adsorption rate)of the functionalized TiO_(2)samples than that of P25(commercial TiO_(2)without modification).Furthermore,there is no obvious loss of the adsorption capacity for the functionalized TiO_(2)even after 5 adsorption-desorption cycles,which indicated the good reusability of the modified TiO_(2)samples for anionic dye removal from aqueous solution.
文摘Amino group protective strategy has consequently emerged in multistep organic synthesis.Easy and selective deprotection procedures are crucial to facilitate the chemical transformation.Recently,Zhang’s group from Henan Normal University collaborating with Chen’s group of Nankai University developed a novel strategy for the regiospecific cleavage of inert aryl C-N bonds in N-aryl amides by hypervalent iodine(V)reagents.These procedures allow removal of sort of aryl groups under mild conditions to give primary amides in high efficiency.It bestows these aryl groups with the characteristics of amino protecting groups that might be the supplement of amino protecting group chemistry.
基金supported by China-USA cooperation for 10+10 program (No. 2009DFA90740),Ministry of Science and Technologysponsored by Science & Technology Commission,Shanghai
文摘Novel amino （-NH2） functionalized mesoporous polyvinyl pyrrolidone （PVP）/SiO2 composite nanofiber membranes were fabricated by a one-step electrospinning method using poly （vinyl alcohol） and tetraethyl orthosilicate （TEOS） mixed with cationic surfactant, cety｜trimethyl ammonium bromide （CTAB） as the structure directing agent. Ureidopropyltriethoxysilane was used for functionalization of the internal pore surfaces. The membranes were characterized by scanning electron microscopy （SEM）, high-resolution transmission electron microscopy （HRTEM） images, X-ray diffraction （XRD）, Fourier-transform infrared spectroscopy （FT-IR）, element analyzer and Nz adsorption-desorption isotherms, The nanofiber diameters, average pore diameters and surface areas were 100-700 nm, 2.86 nm and 873,62 m2/g, respectively. These mesoporous membranes functionalized with -NH2 groups exhibited very high adsorptions properties based on the adsorption of Cr3＋ from an aqueous solution. Equilibrium adsorption was achieved after approximately 20 rain and more than 97% of chronium ions in the solution were removed. The membrane could be regenerated through acidification.
基金financially supported by the National Natural Science Foundation of China(Nos.51504073 and 51404081)the Joint Research Program of the Science and Technology Department of Guizhou Province(No.QianKeHe LH [2014] 7373)+1 种基金the Research Program of the Education Department of Guizhou Province (No.QianJiaoKeHe KY [2015]433)the Research Program of Talented Scholars of Guizhou Institute of Technology (No.XJG20141104)
文摘Monodispersed poly（glycidyl methacrylate）（PGMA） microspheres with various amounts of amino groups（PGMA-NH2） were used to adsorb Au（Ⅲ） from simulated wastewaters. Gold nanoparticle-coated PGMA functional microspheres can be directly obtained via the adsorption process. The adsorption kinetics follows pseudo-second model, and 10 min is enough for reaching at equilibrium. The adsorption isotherm follows Langmuir model, and the adsorption amounts for Au（Ⅲ） are 8.25 and 21.75 mol·kg^-1 at 298 and 328 K, respectively. The relative separation coefficients between Au（Ⅲ）, Pt（Ⅵ）, Pd（Ⅱ）and Co（Ⅱ）, Cu（Ⅱ）; Ni（Ⅱ）, Fe（Ⅲ） are all higher than 100 when 1 〈 pH 〈 3. Furthermore, the characterization analysis of X-ray diffraction（XRD）, thermogravimetrydifferential scanning calorimetry（TG-DSC）, scanning electron microscopy-energy dispersive spectroscopy（SEM-EDS）, transmission electron microscopy（TEM） and Fourier transform infrared spectroscopy（FTIR） confirms that AuCl4^-has been reduced to Au^0 nanoparticles and deposited onto the surface of PGMA-NH2. The current work shows a good prospect for PGMA-NH2 to be a valid adsorbent for the recovery of gold and the possible fabrication of gold nanoparticles by reduction-deposition process without any reductant.
文摘A novel phthalonitrile derivative containing an amino group, 3,5-bis（3,4-dicyanophenoxy）aniline （CPA）, was synthesized via a nucleophilic displacement of 4-nitrophthalonitrile and 5-aminoresorcinol hydrochloride. The structure of CPA was confirmed by Fourier transform infrared spectra （FT-IR） and nuclear magnetic resonance （^1H NMR）. Thermal analysis performed on CPA revealed that the novel phthalonitrile derivative showed a self-promotion curing behavior and the resulting polymer exhibited outstanding heat-resistance.
基金financially supported by the National Natural Scientific Foundation of China(Nos.51073026 and 21004004)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Nos.2009110111003 l and 20101101120029)Excellent Young Scholars Research Fund of Beijing Institute of Technology(No.2009Y0914)
文摘Poly（phenylene ethynylene）s （P1） with 4-vinylaniline pendant groups were successfully prepared by the Sonogashira coupling polymerization bevween 1,4-diethynyl-2,5-bis（pentyloxy）benzene and 4-[2-（2,5-dibromophenyl）vinyl]- aniline. In comparison with its analogue P2 without amino group, the emission of F＇I is only enihanced by aggregation when adding n-hexane into its THF solution, exhibiting an aggregation-induced emission enhancement （AIEE） effect. When methanol or water instead of hexane was added into THF solution, P1, however, didn＇t show AII：~E. The results indicated that amino groups strengthen the inter-chain and intra-chain interactions in P1 and restrict the no^-radiative energy transition. This strategy can provide a platform for developing highly sensitive and efficient bio- and chemosensors.
基金supported by the“Double FirstClass”University Project(No.CPU2018GY08)the Drug Innovation Major Project(No.2018ZX09711-001-007)。
文摘Buxrugulosides A–E,four lignan glycosides(1–4)and a protocatechuate derivative(5)featuring a rare(N,Ndiethyl)methyl amino group at aromatic rings,were obtained from the aerial parts of Buxus rugulosa,which is famous for treating coronary heart disease.Their structures including absolute configurations were elucidated by HRMS,1 D and 2 D NMR,and by comparing their CD data with previous reports.Compound 1 was a rare sesquilignan,and all of these compounds were the first example of lignans with(N,N-diethyl)methyl amino group.
基金Supported by the Educational Commission of Anhui Province(KJ2014ZD02)the National Natural Science Foundation of China(51432001)
文摘A novel D-π-A type α-cyanostilbenzene derivative,（Z）-2-（4-aminophenyl）-3-（4-bromophenyl）-acrylonitrile（ABAN）, was designed and synthesized, by introducing an electrondonating amino group and a heavy atom. The structure of ABAN was confirmed by FT-IR, 1H NMR, 13 C NMR spectra and single-crystal X-ray diffraction analysis. The ABAN is of orthorhombic system, space group P212121, with a = 8.6100（14）, b = 9.6923（16）, c = 15.705（3） , Mr = 299.17, V = 1310.6（4） 3, Z = 4, Dc = 1.516 g/cm-3, μ = 3.119 mm-1, F（000） = 600, Rint = 0.038, R（I 〉 2σ（I）） = 0.0276, w R（I 〉 2σ（I）） = 0.0628, R（all data） = 0.0324, wR（all data） = 0.0646, completeness to theta = 25.00 was 99.8% and GOOF = 1.04. In the crystal structure, ABAN molecules were linked with each other through intermolecular C–H···π interactions and N–H···N hydrogen bonds, by which the 1D chain, 2D plane and 3D stacking structures were constructed. The photophysical properties and calculation results confirmed that ABAN possessed an intramolecular charge transfer（ICT） process. ABAN could be applied into the optoelectronic material field due to good solvent-tuned photophysical properties and highly thermal stability.
文摘Effective CO_(2) adsorption and fast electron injection are two crucial processes of photocatalysts for achieving high-efficiency CO_(2) photo-reduction.However,simultaneously enhancing these processes within a single photocatalyst remains a challenging task.Herein,we propose an intriguing edge effect based on the intrinsic atomic structure of g-C_(3)N_(4) nanosheets(NSs)to enhance their CO_(2) adsorption and facilitate the transfer of photo-generated electrons to the adsorbed CO_(2).By cutting large pieces of g-C_(3)N_(4) NSs into smaller fragments,the exposure of amino groups at the edges of its repeating tri-s-triazine units can be significantly increased.These edge-exposed amino groups serve as active sites for enhancing the CO_(2) capture capacity of g-C_(3)N_(4) NSs.As we decrease the lateral size of g-C_(3)N_(4) NSs from tens of micrometers to hundreds of nanometers,their CO_(2) adsorption capacity increases from 4.74 to 8.56 cm^(3) g^(-1).Reducing the size of g-C_(3)N_(4) NSs also facilitates the transfer of photo-generated electrons to the edge-adsorbed CO_(2).Thus,our optimized g-C_(3)N_(4) NSs with the edge effect exhibits a 37-fold enhancement in activity for CO_(2) photo-reduction compared to normal g-C_(3)N_(4) NSs under simulated sunlight irradiation.Notably,by introducing Pt cocatalysts,we can control product selectivity from 85.9%CO to 97.9%CH_(4).
基金Project supported by the National Natural Science Foundation of China (No. 50578073)the Natural Science Foundation of Jiangsu Province, China (No. 2004088)the Major Projects of Environment Protection Office of Jiangsu Province, China (No. 2004001).
文摘Two novel polymers （NJ-1 and N J-2） were synthesized by chemically modified a hypercrosslinked polymer NJ-0 with dimethylamine and trimethylamine, respectively. The comparison of the adsorption properties of the three polymers toward phenol, resorcin and phloroglucin was made. The study focused on the static equilibrium adsorption behaviors and the adsorption thermodynamics. Freundlich equation was found to fit the adsorption results well. The effect of amino groups introduced onto the surface of the resin and the structure of phenolic compounds on the adsorption were also studied. The hydrogen-bonding interaction and electrostatic interaction could happen between the amino groups and the adsorbates. The adsorption impetus increased as quantity of hydroxyl groups increased, but the adsorption capacity decreased due to the drop of the matching degree of the aperture of resins and the diameter of adsorbate molecules.
基金Project supported by the National Natural Science Foundation of China(22002056,21663016,21961021)the Key Laboratory of Jiangxi Province for Environment and Energy Catalysis(20181BCD40004)the Research Project on Teaching Reform of Degree and Graduate Education of Jiangxi Province(JXYJG-2018-007)。
文摘Bearing unique redox nature and high oxygen storage capacity,ceria(CeO_(2))has always been a promising CO oxidation catalyst support for gold(Au)catalysts and the like.Herein,a series of Au-CeO_(2)-P(P stands for pH value)samples was prepared by a co-precipitation method with the assistance of an alkaline environment and amino groups functionalized ordered mesoporous polymer(OMP-NH_(2)).Afterward,all samples described above were characterized that the Au-CeO_(2)-P catalysts are made of Au-Ce-O solid solution and Au nanoparticles(NPs)supported on CeO_(2).It turns out that OMP-NH_(2) is not just a simple sacrificial template for mesoporous structure,but also plays an important role as an amino source,explaining the presence of rich oxygen vacancies.Due to the concentration of oxygen vacancies in Au-Ce-O solid solution is the key factor for the oxygen mobility of CO oxidation,the catalytic results also demonstrate that the catalytic activity of Au-CeO_(2)-P catalysts is related to the concentration of their oxygen vacancies.Moreover,Au-CeO_(2)-9.6 with a highest concentration of oxygen vacancies(as high as 13.98%)in Au-CeO_(2)-P catalysts exhibits the best catalytic activity(complete conversion at 10℃).
文摘Until now, automation in nanomaterial research has been largely focused on the automated synthesis of engineered nanoparticles (NPs) including the screening of synthesis parameters and the automation of characterization methods such as electron microscopy. Despite the rapidly increasing number of NP samples analyzed due to increasing requirements on NP quality control, increasing safety concerns, and regulatory requirements, automation has not yet been introduced into workflows of analytical methods utilized for screening, monitoring, and quantifying functional groups (FGs) on NPs. To address this gap, we studied the potential of simple automation tools for the quantification of amino surface groups on different types of aminated NPs, varying in size, chemical composition, and optical properties, with the exemplarily chosen sensitive optical fluorescamine (Fluram) assay. This broadly applied, but reportedly error-prone assay, which utilizes a chromogenic reporter, involves multiple pipetting and dilution steps and photometric or fluorometric detection. In this study, we compared the influence of automated and manual pipetting on the results of this assay, which was automatically read out with a microplate reader. Special emphasis was dedicated to parameters like accuracy, consistency, achievable uncertainties, and speed of analysis and to possible interferences from the NPs. Our results highlight the advantages of automated surface FG quantification and the huge potential of automation for nanotechnology. In the future, this will facilitate process and quality control of NP fabrication, surface modification, and stability monitoring and help to produce large data sets for nanomaterial grouping approaches for sustainable and safe-by-design, performance, and risk assessment studies.
基金Supported by the National Basic Research Program of China (2007CB613507)
文摘The magnetic poly-（methacrylate-divinyl benzene） microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr（VI） from aqueous solution by magnetic poly-（MA-DVB） microspheres with surface amination was investigated. The adsorption processes were carried out under diversified conditions of pH value, adsorption time and temperature to evaluate the perlbrmance of the magnetic microspheres. The optimum pH value for Cr（VI） adsorption was found as 3. The adsorption capacity increased with adsorption time and attained an optimum at 60 rain. The adsorption processes for magnetic microspheres was endothermic reaction, and the adsorption capacity increased with increasing temperature.
