Aminated tannins were prepared by reacting mimosa condensed tannin extract with ammonia yielding the substitution of many,if not all of the tannin hydroxyl groups with–NH_(2)groups.A tannin-aminated tannin(ATT)partic...Aminated tannins were prepared by reacting mimosa condensed tannin extract with ammonia yielding the substitution of many,if not all of the tannin hydroxyl groups with–NH_(2)groups.A tannin-aminated tannin(ATT)particleboard coating was then prepared by reacting raw tannin extract with aminated tannin extract and thus cross-linking the two by substituting tannin’s hydroxyl groups with the–NH_(2)groups on the aminated tannin to form–NH-bridges between the two.The resulting particleboard coating gave encouraging results when pressed at 180℃for 3 min.Conversely,the system in which tannin was reacted/cross-liked with urea(ATU)by a similar amination reaction did not perform as well as the ATT system,and this even when a higher curing temperature and longer hot press time were used.In particular its water repellence was worse probably due to the presence of urea and such a system with lower reactivity.Nonetheless,substituting the tannin–OHs with the urea–NH_(2)groups appeared to also take place.ATT gave better results than ATU as regards water repellence and mechanical resistance as shown by the cross cut test.The ATT system was shown to be between 95%and 98%biosourced.The difference appeared to be due,by TMA analysis,to the much faster formation of the ATT hardened network leading to a better cross-linked polymer coating.The chemical species formed for both the ATT and ATU system were studied by MALDI ToF and CP MAS^(13)C NMR.展开更多
Konjac glucomannan (KGM) was aminated by 2-chloroethyl-amine (CEA) as reagent so as to study the influence of concentration of CEA (based on the amount of KGM), concentration of NaOH, reaction time and temperatu...Konjac glucomannan (KGM) was aminated by 2-chloroethyl-amine (CEA) as reagent so as to study the influence of concentration of CEA (based on the amount of KGM), concentration of NaOH, reaction time and temperature on the extent of amination. And the molecular simulation technology was adopted to analyze the conformation stability of aminate (AKGM). The results indicate that when the amount of CEA is higher, the extent of amination is higher. The optimum concentration of NaOH, reaction time and temperature are 10% NaOH, 70 ℃ and 45 rain, respectively. IR shows KGM is successfully aminated. The conformation of AKGM is in a random clew-like shape.展开更多
An aminated hypercrosslinked macroporous polymeric adsorbent was synthesized and characterized. Adsorption isotherms for 1 amino 2 naphthol 4 sulfonic acid(1, 2, 4 acid) and 2 naphthol obtained from various bin...An aminated hypercrosslinked macroporous polymeric adsorbent was synthesized and characterized. Adsorption isotherms for 1 amino 2 naphthol 4 sulfonic acid(1, 2, 4 acid) and 2 naphthol obtained from various binary adsorption environments can be well fitted by Freundlich equation, which indicated a favorable adsorption process in the studied range. Adsorption for 1, 2, 4 acid was an endothermic process in comparison with that for 2 naphthol of an exothermic process. 2 naphthol molecules put a little influence on the adsorption capacity for 1, 2, 4 acid. However, the adsorption to 1, 2, 4 acid depressed that to 2 naphthol in a large extent for the stronger electrostatic interaction between 1, 2, 4 acid and adsorbent. The predominant mechanism can be contributed to the competition for adsorption sites. And the simultaneous environment was confirmed to be helpful to the selective adsorption towards 1,2,4 acid based on the larger selectivity index.展开更多
The new flow improvers for super-viscous crude oils were developed via esterification of polybasic high carbon alcohol with methacrylate and copolymerizafion of monomers followed by amination of copolymers. The struct...The new flow improvers for super-viscous crude oils were developed via esterification of polybasic high carbon alcohol with methacrylate and copolymerizafion of monomers followed by amination of copolymers. The structure of the synthesized polymer flow improver additive was confirmed by IR spectroscopy and the crystal structure of the flow improver additives were determined by X-ray diffrac- tion analysis. The structure of wax crystals was also studied at the same time. The results showed that the wax crystal structure was closely related with the crystal structure of the flow improver, which could change the pour point depression and viscosity reduction behavior of the crude oil. When the wax crystal structure matched well with that of the additive, the wax crystals were dispersed satisfactorily, resulting in favorable effects in terms of pour point depression and viscosity reduction. The new synthe- sized aminated polymer flow improver additive was most efficient for treating super-viscous crude oils. The super-viscous crude oil had a high content of resins and asphaltenes, which might aggregate onto the surface of wax crystals to form blocks to limit the crude oil fluidity. However, amination of copolymers having similar structure with the resins and asphaltenes contained in crude oil could dissolve the huge polar groups to make the deposit formation difficult.展开更多
In the present study we prepared macroporous polyvinyl alcohol beads. A series of bilirubin adsorbents were generated by immobilization of eight amine agents to the beads as ligands. The adsorption of bilirubin was ev...In the present study we prepared macroporous polyvinyl alcohol beads. A series of bilirubin adsorbents were generated by immobilization of eight amine agents to the beads as ligands. The adsorption of bilirubin was evaluated by in vitro static and dynamic adsorption tests. The results show that these adsorbents have excellent adsorption efficiency and capacity. Among the eight ligands, trimethylamine (TMA), triethylamine (TEA) and 1,6- hexanediamine (HDA) showed the highest adsorption capacity. The adsorption equilibrium can be achieved in half an hour, and the adsorption percentage of bilirubin was up to 80%. Static electricity and hydrophobie interaction played the main role in bilirubin adsorption, and the adsorption was found to match the monolayer model. The excellent adsorption of these adsorbents indicates their potential in clinical treatment.展开更多
Recently biospecific affinity chromatography has been widely used for the separation and purification of various enzymes and nucleic acids. In this paper, a series of synthetic reactions of solid-liquid phase were car...Recently biospecific affinity chromatography has been widely used for the separation and purification of various enzymes and nucleic acids. In this paper, a series of synthetic reactions of solid-liquid phase were carried out on silica surface, using a macroporous(30 mu m), microspherical silica (8 mu m) as the matrix and gamma-aminopropyltriethoxysilane as the activating agent, the nicotinamide adenine dinucleotide(NAD) was bonded through its amino groups to the carboxylic groups of linked phospholipid which was bonded covalently on aminated support. The bonded stationary phase has high thermal stability, and could be used to separate of nucleotides with good resolution.展开更多
H-terminated DLC layers were synthesized on SiO 2 substrate by radio frequency (RF) magnetron plasma-enhanced chemical vapor deposition (PECVD) in a conventional reactor using C 4 H 10 as carbon source. As-deposited D...H-terminated DLC layers were synthesized on SiO 2 substrate by radio frequency (RF) magnetron plasma-enhanced chemical vapor deposition (PECVD) in a conventional reactor using C 4 H 10 as carbon source. As-deposited DLC films were characterized by Raman spectroscopy, scanning electron microscopy (SEM) as well as atomic force microscopy (AFM). The chemical reactivity of the obtained DLC surface was further investigated by exposing the photochemically oxidized DLC surface to a silane reagent. The course of the reaction was followed using water contact angle and X-ray photoelectron spectroscopy.展开更多
Peroxidase plays an important role in living systems;however,its storage difficulty and easy inactivation have limited its applications in complex environments.To address these problems,herein,we proposed a method to ...Peroxidase plays an important role in living systems;however,its storage difficulty and easy inactivation have limited its applications in complex environments.To address these problems,herein,we proposed a method to synthesize peroxidase mimics by amination,carbonization,and Fe^(3+)-doping of industrial alkali lignin.The Fe^(3+)-doped lignin-based peroxidase mimic(Fe-LPM),with active centers of coordination between Fe^(3+)and N atoms,showed higher tolerance to pH value and temperature than natural peroxidase.Using Fe-LPM,10-100 mmol/L of H_(2)O_(2) and glucose could be colorimetrically detected with the lowest detection limits of 80μmol/L and 1.5 mmol/L and visual detection limits of 1.0 mmol/L and 10 mmol/L,respectively.The Fe-LPM maintained peroxidase-like activity after 10 cycles and could even be used for H_(2)O_(2) detection in practical samples.This work not only provides a new approach to synthesize peroxidase mimics using biomass materials but also promotes the high-value utilization of lignin.展开更多
A new method for the preparation of aminated lignin (AEL) through etherification and amination reaction was presented. Chlorine atoms were ?rstly introduced into lignin through its etheri?cation with epichlo...A new method for the preparation of aminated lignin (AEL) through etherification and amination reaction was presented. Chlorine atoms were ?rstly introduced into lignin through its etheri?cation with epichlorohydrin. Then, hydrophilic amine groups were grafted to the modi?ed lignin structure through amination with ethylenediamine to obtain AEL. Subsequent acidi?cation of AEL led to the ionized aminated lignin (IAEL). The results of our analyses showed that the nitrogen content of AEL was 6.9%. Foaming and emulsifying experiments indicated that AEL had better foamability and emulsifying properties than IAEL. Surface tension tests showed that AEL and IAEL had similar critical micelle concentration (CMC). However, IAEL had lower surface tension (36.33 mN/m) than AEL (42.89 mN/m) at CMC. These results demonstrate the promising applicability of AEL as an emulsi?er and that of IAEL as feedstock in the production of detergent and dispersant.展开更多
A new aminated-perylenequinone derivative 2 was synthesized by the reaction of 1 (hypocrellin B) with 6-aminohexanoic-acid. The structure of 2 was identified by UV-Vis, MS, IR and H-1-NMR. Thc amphiphility spectrum an...A new aminated-perylenequinone derivative 2 was synthesized by the reaction of 1 (hypocrellin B) with 6-aminohexanoic-acid. The structure of 2 was identified by UV-Vis, MS, IR and H-1-NMR. Thc amphiphility spectrum and photochemical properties of 2 were reported.展开更多
The surface of a biowaste was modified by introduction of amino group for the purification of wastewater contaminated with heavy metals. In this study waste tea leaf was used as a biowaste which was an economic and ef...The surface of a biowaste was modified by introduction of amino group for the purification of wastewater contaminated with heavy metals. In this study waste tea leaf was used as a biowaste which was an economic and efficient bioadsorbent. The aminated tea leaves were characterized by spectral and elemental analysis. The adsorption capacity of the surface modified biosorbent was studied as the function of solution pH, concentration of metal ions and contact time of adsorption. The applicability of Langmuir isotherm was tested. The adsorption capacities were found to be 83.04 mg/g and 57 mg/g for Pb (II) and Cd (II), respectively. The biosorbent was regenerated by desorption of the metal loaded adsorbent with 0.1 M HNO3. These results showed that the aminated tea leaves may be an attractive alternative for treatment of wastewater contaminated with heavy metals.展开更多
Herein,a Fe^(3+)-loaded aminated polypropylene fiber has been reported as an efficient phosphate adsorbent.The remarkable phosphate removal ability of the fiber is due to Fe^(3+)immobilization,and it demonstrates a ma...Herein,a Fe^(3+)-loaded aminated polypropylene fiber has been reported as an efficient phosphate adsorbent.The remarkable phosphate removal ability of the fiber is due to Fe^(3+)immobilization,and it demonstrates a maximum adsorption capacity of 33.94 mg·P·g^(–1).Adsorption experiments showed that the fiber is applicable over a wide pH range from 2 to 9.Furthermore,the adsorption kinetics and isotherm data were consistent with the pseudo-second-order and Langmuir adsorption models,respectively.The adsorption equilibrium of the fiber for phosphate was reached within 60 min,indicating an efficient monolayer chemisorption process.Moreover,the adsorbent maintained prominent phosphate removal in the presence of competitive ions such as NO_(3)^(–)and Cl^(–),exhibiting high selectivity.More importantly,the fiber demonstrated excellent reusability(5 times)and low adsorption limit below 0.02 mg·P·g^(–1).In addition,the phosphate removal efficiency of the fiber can exceed 99%under continuous flow conditions.The adsorption mechanism was studied by X-ray photoelectron spectroscopy,showing that the adsorption of phosphate on the fiber mainly depended on the chemical adsorption of the modified Fe^(3+).Overall,this study proves that the fiber possesses many advantages for phosphate removal,including high adsorption efficiency,lower treatment limit,good recyclability,and environmental friendliness.展开更多
A hybrid membrane consisted of aminated graphene and Ag nanoparticles(Ag NPs) was prepared on the surface of glassy carbon electrode(GCE) by cyclic voltammetry(CV) with aminated graphene(GR-NH2) as matrix for ...A hybrid membrane consisted of aminated graphene and Ag nanoparticles(Ag NPs) was prepared on the surface of glassy carbon electrode(GCE) by cyclic voltammetry(CV) with aminated graphene(GR-NH2) as matrix for immobilizing Ag NPs.The morphology and electrochemical properties of this hybrid membrane were characterized by scanning electron microscopy(SEM) and CV,respectively,and on this membrane,the voltammetric behaviors of epinephrine(EP) were studied in detail.The membrane exhibited excellent eletro-catalytic activities for the redox of EP,and could resolve the electrochemical response of EP and uric acid(UA) into two oxidation peaks.The peak current of EP was linear with its concentration in the ranges of 0.916-18.3 μmol/L and 18.3-184 μmol/L.The detection limit was 2.0 nmol/L(S/N=3).The proposed modified electrode retained the advantages of easy fabrication,high sensitivity and good repeatability for the determination of EP.展开更多
Functional fullerene derivatives exhibit special inhibitory effects on tumor progress and metastasis via diverse tumor microenvironment regulations,while the elusive molecular mechanisms hinder their clinical transfor...Functional fullerene derivatives exhibit special inhibitory effects on tumor progress and metastasis via diverse tumor microenvironment regulations,while the elusive molecular mechanisms hinder their clinical transformation.Herein,it is initially revealed that nanosize aminated fullerene(C_(70)-EDA)can activate autophagic flux,induce G0/G1 cell cycle arrest to abrogate cancer cell proliferation,and significantly inhibit tumor growth in vivo.Mechanismly,C_(70)-EDA promotes the expression of cathepsin D involved in autophagic activation via post-transcriptional regulation,attributing to the interaction with a panel of RNA binding proteins.The accumulation of cathepsin D induces the autophagic degradation of cyclin D1,which arouses G0/G1 phase arrest.This work unveils the fantastic anti-tumor activity of aminated fullerene,elucidates the molecular mechanism,and provides a new strategy for the antineoplastic drug development on functional fullerenes.展开更多
Reported here is the synthesis of a new macrocycle bearing anionic carboxylate groups with water-soluble aggregation-induced emission(AIE).The water-soluble macrocycle without typical AIE luminogens is constructed bas...Reported here is the synthesis of a new macrocycle bearing anionic carboxylate groups with water-soluble aggregation-induced emission(AIE).The water-soluble macrocycle without typical AIE luminogens is constructed based on the building block of benzothiadiazole.It exhibits a remarkable AIE effect.This watersoluble macrocycle can selectively bind different types of biogenic amines in aqueous media with the tightest binding towards spermine.The fluorescence enhancement induced by supramolecular encapsulation is used to detect spermine.展开更多
Direct air capture(DAC)of CO_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission technologies.Since large air flows are required to capture the ultradilute CO_(2)from t...Direct air capture(DAC)of CO_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission technologies.Since large air flows are required to capture the ultradilute CO_(2)from the air,lab-synthesized adsorbents in powder form may cause unacceptable gas pressure drops and poor heat and mass transfer efficiencies.A structured adsorbent is essential for the implementation of gas-solid contactors for cost-and energy-efficient DAC systems.In this study,efficient adsorbent poly(ethyleneimine)(PEI)-functionalized Mg-Al-CO_(3)layered double hydroxide(LDH)-derived mixed metal oxides(MMOs)are three-dimensional(3D)printed into monoliths for the first time with more than 90%adsorbent loadings.The printing process has been optimized by initially printing the LDH powder into monoliths followed by calcination into MMO monoliths.This structure exhibits a 32.7%higher specific surface area and a 46.1%higher pore volume,as compared to the direct printing of the MMO powder into a monolith.After impregnation of PEI,the monolith demonstrates a large adsorption capacity(1.82 mmol/g)and fast kinetics(0.7 mmol/g/h)using a CO_(2)feed gas at 400 ppm at 25℃,one of the highest values among the shaped DAC adsorbents.Smearing of the amino-polymers during the post-printing process affects the diffusion of CO_(2),resulting in slower adsorption kinetics of pre-impregnation monoliths compared to post-impregnation monoliths.The optimal PEI/MeOH ratio for the post-impregnation solution prevents pores clogging that would affect both adsorption capacity and kinetics.展开更多
Fe-based Prussian blue(Fe-PB)cathode material shows great application potential in sodium(Na)-ion batteries due to its high theoretical capacity,long cycle life,low cost,and simple preparation process.However,the crys...Fe-based Prussian blue(Fe-PB)cathode material shows great application potential in sodium(Na)-ion batteries due to its high theoretical capacity,long cycle life,low cost,and simple preparation process.However,the crystalline water and vacancies of Fe-PB lattice,the low electrical conductivity,and the dissolution of metal ions lead to limited capacity and poor cycling stability.In this work,a perylene tetracarboxylic dianhydride amine(PTCDA)coating layer is successfully fabricated on the surface of Fe-PB by a liquid-phase method.The aminated PTCDA(PTCA)coating not only increases the specific surface area and electronic conductivity but also effectively reduces the crystalline water and vacancies,which avoids the erosion of Fe-PB by electrolyte.Consequently,the PTCA layer reduces the charge transfer resistance,enhances the Na-ion diffusion coefficient,and improves the structure stability.The PTCA-coated Fe-PB exhibits superior Na storage performance with a first discharge capacity of 145.2 mAh g^(−1) at 100 mA g^(−1).Long cycling tests exhibit minimal capacity decay of 0.027%per cycle over 1000 cycles at 1 A g^(−1).Therefore,this PTCA coating strategy has shown promising competence in enhancing the electrochemical performance of Fe-PB,which can potentially serve as a universal electrode coating strategy for Na-ion batteries.展开更多
The effect of the presence of trace SO_(2)in industrial flue gas on the amine-scrubbing-based absorption process for CO_(2)capture has been a matter of concern.This study aimed to investigate the effect of trace SO_(2...The effect of the presence of trace SO_(2)in industrial flue gas on the amine-scrubbing-based absorption process for CO_(2)capture has been a matter of concern.This study aimed to investigate the effect of trace SO_(2)on the CO_(2)capture process using piperazine-based amine absorbents,focusing on SO_(2)-resistance capability,SO_(2)/CO_(2)absorption selectivity,and cyclic stability.The presence of trace SO_(2)not only restrains CO_(2)absorption,but also promotes the formation of carbamate within the piperazine-based amine absorbents.Remarkably,the incorporation of aminoethyl group in piperazine-based amine absorbents can enhance the SO_(2)-resistance capability by promoting the formation of carbamate,while piperazine-based amine absorbents with hydroxyethyl group can promote the formation of bicarbonate to reduce the SO_(2)-resistance capability.The work offers valuable insights into the efficient application of novel amine absorbents for CO_(2)capture from practical industrial flue gas.展开更多
To deepen the understanding in the effect of potassium lactate on the sensory quality and safety of Rugao ham,sensory attributes,physicochemical parameters,total volatile basic nitrogen(TVBN),microorganism community a...To deepen the understanding in the effect of potassium lactate on the sensory quality and safety of Rugao ham,sensory attributes,physicochemical parameters,total volatile basic nitrogen(TVBN),microorganism community and biogenic amines of Rugao ham manufactured with different potassium lactate levels(0%,0.5%,1%,2%)were investigated;the relationship between microbial community and the formation of TVBN and biogenic amines was further evaluated.With the increase of potassium lactate from 0%to 2%,the increased sensory scores and the decreased total aerobic bacterial count and TVBN were observed;the abundance of Staphylococcus increased,while the content of Halomonas decreased.LDA effect size(LEf Se)and correlations analysis showed that Staphylococcus equorum and Lactobacillus fermentum could be the key species to improve sensory scores and decrease biogenic amines and TVBN.Metabolic pathway analysis further showed that amino acids metabolism and nitrogen metabolism were mainly involved in decreasing TVBN and biogenic amines in the treatment of 2%potassium lactate.展开更多
Lactic acid bacteria and coagulase-negative staphylococci play an important role in the production of fermented sausages,such as inhibiting the growth of undesirable bacteria and antioxidant.In this study,the effects ...Lactic acid bacteria and coagulase-negative staphylococci play an important role in the production of fermented sausages,such as inhibiting the growth of undesirable bacteria and antioxidant.In this study,the effects of inoculation with different starter cultures(Lactiplantibacillus plantarum HN108 and Staphylococcus simulans NJ209)on the free amino acids(FAAs),biogenic amines(BAs)and volatile compounds of fermented sausages were investigated using an amino acid analyzer,ultra performance liquid chromatography and gas chromatography-ion mobility spectrometry,respectively.The pH and carbonyl content of the inoculated group was significantly lower than those in the control group(P<0.05).L.plantarum HN108 significantly reduced the content of FAAs and BAs in fermented sausage production(P<0.05),while S.simulans NJ209 promoted the formation of FAAs(especially bitter amino acids)and exhibited slight BAs-reducing activity.In addition,L.plantarum HN108 promoted the formation of volatile compounds such as ketones,alcohols and alkenes in sausages.In conclusion,L.plantarum HN108 could contribute to reducing the content of putrescine and tyramine and forming the desirable flavor compounds in fermented sausages.Thus,L.plantarum HN108 is expected to be a starter culture that can improve the safety and flavor of fermented sausages.展开更多
基金supported by a grant of the French Agence Nationale de la Recherche(ANR)in the Ambit of the Laboratory of Excellence(Labex)ARBRE.This work was also supported by“The 111 Project(D21027)”.
文摘Aminated tannins were prepared by reacting mimosa condensed tannin extract with ammonia yielding the substitution of many,if not all of the tannin hydroxyl groups with–NH_(2)groups.A tannin-aminated tannin(ATT)particleboard coating was then prepared by reacting raw tannin extract with aminated tannin extract and thus cross-linking the two by substituting tannin’s hydroxyl groups with the–NH_(2)groups on the aminated tannin to form–NH-bridges between the two.The resulting particleboard coating gave encouraging results when pressed at 180℃for 3 min.Conversely,the system in which tannin was reacted/cross-liked with urea(ATU)by a similar amination reaction did not perform as well as the ATT system,and this even when a higher curing temperature and longer hot press time were used.In particular its water repellence was worse probably due to the presence of urea and such a system with lower reactivity.Nonetheless,substituting the tannin–OHs with the urea–NH_(2)groups appeared to also take place.ATT gave better results than ATU as regards water repellence and mechanical resistance as shown by the cross cut test.The ATT system was shown to be between 95%and 98%biosourced.The difference appeared to be due,by TMA analysis,to the much faster formation of the ATT hardened network leading to a better cross-linked polymer coating.The chemical species formed for both the ATT and ATU system were studied by MALDI ToF and CP MAS^(13)C NMR.
基金Supported by Foundation of Minnan Normal University,the Funding(type A,No.JA11167)from the Fujian Education DepartmentNational Natural Science Foundation of China(31071518 and 31271837)+2 种基金Joint Specialized Research Fund for the Doctoral Program of Higher Education,MOE(20113515110010)Science and Technology Planning Project of technological department(2012GA7200022)Natural Science Foundation of Fujian Province(2011J01285)
文摘Konjac glucomannan (KGM) was aminated by 2-chloroethyl-amine (CEA) as reagent so as to study the influence of concentration of CEA (based on the amount of KGM), concentration of NaOH, reaction time and temperature on the extent of amination. And the molecular simulation technology was adopted to analyze the conformation stability of aminate (AKGM). The results indicate that when the amount of CEA is higher, the extent of amination is higher. The optimum concentration of NaOH, reaction time and temperature are 10% NaOH, 70 ℃ and 45 rain, respectively. IR shows KGM is successfully aminated. The conformation of AKGM is in a random clew-like shape.
文摘An aminated hypercrosslinked macroporous polymeric adsorbent was synthesized and characterized. Adsorption isotherms for 1 amino 2 naphthol 4 sulfonic acid(1, 2, 4 acid) and 2 naphthol obtained from various binary adsorption environments can be well fitted by Freundlich equation, which indicated a favorable adsorption process in the studied range. Adsorption for 1, 2, 4 acid was an endothermic process in comparison with that for 2 naphthol of an exothermic process. 2 naphthol molecules put a little influence on the adsorption capacity for 1, 2, 4 acid. However, the adsorption to 1, 2, 4 acid depressed that to 2 naphthol in a large extent for the stronger electrostatic interaction between 1, 2, 4 acid and adsorbent. The predominant mechanism can be contributed to the competition for adsorption sites. And the simultaneous environment was confirmed to be helpful to the selective adsorption towards 1,2,4 acid based on the larger selectivity index.
文摘The new flow improvers for super-viscous crude oils were developed via esterification of polybasic high carbon alcohol with methacrylate and copolymerizafion of monomers followed by amination of copolymers. The structure of the synthesized polymer flow improver additive was confirmed by IR spectroscopy and the crystal structure of the flow improver additives were determined by X-ray diffrac- tion analysis. The structure of wax crystals was also studied at the same time. The results showed that the wax crystal structure was closely related with the crystal structure of the flow improver, which could change the pour point depression and viscosity reduction behavior of the crude oil. When the wax crystal structure matched well with that of the additive, the wax crystals were dispersed satisfactorily, resulting in favorable effects in terms of pour point depression and viscosity reduction. The new synthe- sized aminated polymer flow improver additive was most efficient for treating super-viscous crude oils. The super-viscous crude oil had a high content of resins and asphaltenes, which might aggregate onto the surface of wax crystals to form blocks to limit the crude oil fluidity. However, amination of copolymers having similar structure with the resins and asphaltenes contained in crude oil could dissolve the huge polar groups to make the deposit formation difficult.
文摘In the present study we prepared macroporous polyvinyl alcohol beads. A series of bilirubin adsorbents were generated by immobilization of eight amine agents to the beads as ligands. The adsorption of bilirubin was evaluated by in vitro static and dynamic adsorption tests. The results show that these adsorbents have excellent adsorption efficiency and capacity. Among the eight ligands, trimethylamine (TMA), triethylamine (TEA) and 1,6- hexanediamine (HDA) showed the highest adsorption capacity. The adsorption equilibrium can be achieved in half an hour, and the adsorption percentage of bilirubin was up to 80%. Static electricity and hydrophobie interaction played the main role in bilirubin adsorption, and the adsorption was found to match the monolayer model. The excellent adsorption of these adsorbents indicates their potential in clinical treatment.
文摘Recently biospecific affinity chromatography has been widely used for the separation and purification of various enzymes and nucleic acids. In this paper, a series of synthetic reactions of solid-liquid phase were carried out on silica surface, using a macroporous(30 mu m), microspherical silica (8 mu m) as the matrix and gamma-aminopropyltriethoxysilane as the activating agent, the nicotinamide adenine dinucleotide(NAD) was bonded through its amino groups to the carboxylic groups of linked phospholipid which was bonded covalently on aminated support. The bonded stationary phase has high thermal stability, and could be used to separate of nucleotides with good resolution.
基金supported by the National Natural Science Foundation of China (No.51002090)the Outstanding Young Scientist Research Award Fund of Shandong Province (No.BS2010CL028)
文摘H-terminated DLC layers were synthesized on SiO 2 substrate by radio frequency (RF) magnetron plasma-enhanced chemical vapor deposition (PECVD) in a conventional reactor using C 4 H 10 as carbon source. As-deposited DLC films were characterized by Raman spectroscopy, scanning electron microscopy (SEM) as well as atomic force microscopy (AFM). The chemical reactivity of the obtained DLC surface was further investigated by exposing the photochemically oxidized DLC surface to a silane reagent. The course of the reaction was followed using water contact angle and X-ray photoelectron spectroscopy.
基金The authors are grateful for the financial support by the
文摘Peroxidase plays an important role in living systems;however,its storage difficulty and easy inactivation have limited its applications in complex environments.To address these problems,herein,we proposed a method to synthesize peroxidase mimics by amination,carbonization,and Fe^(3+)-doping of industrial alkali lignin.The Fe^(3+)-doped lignin-based peroxidase mimic(Fe-LPM),with active centers of coordination between Fe^(3+)and N atoms,showed higher tolerance to pH value and temperature than natural peroxidase.Using Fe-LPM,10-100 mmol/L of H_(2)O_(2) and glucose could be colorimetrically detected with the lowest detection limits of 80μmol/L and 1.5 mmol/L and visual detection limits of 1.0 mmol/L and 10 mmol/L,respectively.The Fe-LPM maintained peroxidase-like activity after 10 cycles and could even be used for H_(2)O_(2) detection in practical samples.This work not only provides a new approach to synthesize peroxidase mimics using biomass materials but also promotes the high-value utilization of lignin.
基金supported by the Research Project for Hot Tracking Items of Beijing Forestry University(2017BLRD03)the National Natural Science Foundation of China(51603012)+1 种基金the Special Science and Technology Research Program of Beijing Forestry University(2016KJ02)the Fundamental Research Funds for the Central Universities(BLYJ2016-17,BLX2015-06)
文摘A new method for the preparation of aminated lignin (AEL) through etherification and amination reaction was presented. Chlorine atoms were ?rstly introduced into lignin through its etheri?cation with epichlorohydrin. Then, hydrophilic amine groups were grafted to the modi?ed lignin structure through amination with ethylenediamine to obtain AEL. Subsequent acidi?cation of AEL led to the ionized aminated lignin (IAEL). The results of our analyses showed that the nitrogen content of AEL was 6.9%. Foaming and emulsifying experiments indicated that AEL had better foamability and emulsifying properties than IAEL. Surface tension tests showed that AEL and IAEL had similar critical micelle concentration (CMC). However, IAEL had lower surface tension (36.33 mN/m) than AEL (42.89 mN/m) at CMC. These results demonstrate the promising applicability of AEL as an emulsi?er and that of IAEL as feedstock in the production of detergent and dispersant.
基金the National Natural Science Foundation of China (Project No.39830090 and No.39970871) for their financial support to this resea
文摘A new aminated-perylenequinone derivative 2 was synthesized by the reaction of 1 (hypocrellin B) with 6-aminohexanoic-acid. The structure of 2 was identified by UV-Vis, MS, IR and H-1-NMR. Thc amphiphility spectrum and photochemical properties of 2 were reported.
文摘The surface of a biowaste was modified by introduction of amino group for the purification of wastewater contaminated with heavy metals. In this study waste tea leaf was used as a biowaste which was an economic and efficient bioadsorbent. The aminated tea leaves were characterized by spectral and elemental analysis. The adsorption capacity of the surface modified biosorbent was studied as the function of solution pH, concentration of metal ions and contact time of adsorption. The applicability of Langmuir isotherm was tested. The adsorption capacities were found to be 83.04 mg/g and 57 mg/g for Pb (II) and Cd (II), respectively. The biosorbent was regenerated by desorption of the metal loaded adsorbent with 0.1 M HNO3. These results showed that the aminated tea leaves may be an attractive alternative for treatment of wastewater contaminated with heavy metals.
基金This work was financially supported by the National Natural Science Foundation of China(Grant No.22208003)Natural Science Foundation of Anhui Province(No.1908085QB87)Major Science and Technology Projects in Anhui Province(No.202103a06020012).
文摘Herein,a Fe^(3+)-loaded aminated polypropylene fiber has been reported as an efficient phosphate adsorbent.The remarkable phosphate removal ability of the fiber is due to Fe^(3+)immobilization,and it demonstrates a maximum adsorption capacity of 33.94 mg·P·g^(–1).Adsorption experiments showed that the fiber is applicable over a wide pH range from 2 to 9.Furthermore,the adsorption kinetics and isotherm data were consistent with the pseudo-second-order and Langmuir adsorption models,respectively.The adsorption equilibrium of the fiber for phosphate was reached within 60 min,indicating an efficient monolayer chemisorption process.Moreover,the adsorbent maintained prominent phosphate removal in the presence of competitive ions such as NO_(3)^(–)and Cl^(–),exhibiting high selectivity.More importantly,the fiber demonstrated excellent reusability(5 times)and low adsorption limit below 0.02 mg·P·g^(–1).In addition,the phosphate removal efficiency of the fiber can exceed 99%under continuous flow conditions.The adsorption mechanism was studied by X-ray photoelectron spectroscopy,showing that the adsorption of phosphate on the fiber mainly depended on the chemical adsorption of the modified Fe^(3+).Overall,this study proves that the fiber possesses many advantages for phosphate removal,including high adsorption efficiency,lower treatment limit,good recyclability,and environmental friendliness.
基金Supported by the National Natural Science Foundation of China(No.21105023) and the Natural Science Foundation of Shandong Province,China(Nos.BS2013HZ027,ZR2009BM003).
文摘A hybrid membrane consisted of aminated graphene and Ag nanoparticles(Ag NPs) was prepared on the surface of glassy carbon electrode(GCE) by cyclic voltammetry(CV) with aminated graphene(GR-NH2) as matrix for immobilizing Ag NPs.The morphology and electrochemical properties of this hybrid membrane were characterized by scanning electron microscopy(SEM) and CV,respectively,and on this membrane,the voltammetric behaviors of epinephrine(EP) were studied in detail.The membrane exhibited excellent eletro-catalytic activities for the redox of EP,and could resolve the electrochemical response of EP and uric acid(UA) into two oxidation peaks.The peak current of EP was linear with its concentration in the ranges of 0.916-18.3 μmol/L and 18.3-184 μmol/L.The detection limit was 2.0 nmol/L(S/N=3).The proposed modified electrode retained the advantages of easy fabrication,high sensitivity and good repeatability for the determination of EP.
基金This work was supported by the National Natural Science Foundation of China(No.51802310)All animal experiments were conducted according to protocols approved by the Institutional Animal Care and Use Committee in the Institute of Chemistry,Chinese Academy of Sciences.
文摘Functional fullerene derivatives exhibit special inhibitory effects on tumor progress and metastasis via diverse tumor microenvironment regulations,while the elusive molecular mechanisms hinder their clinical transformation.Herein,it is initially revealed that nanosize aminated fullerene(C_(70)-EDA)can activate autophagic flux,induce G0/G1 cell cycle arrest to abrogate cancer cell proliferation,and significantly inhibit tumor growth in vivo.Mechanismly,C_(70)-EDA promotes the expression of cathepsin D involved in autophagic activation via post-transcriptional regulation,attributing to the interaction with a panel of RNA binding proteins.The accumulation of cathepsin D induces the autophagic degradation of cyclin D1,which arouses G0/G1 phase arrest.This work unveils the fantastic anti-tumor activity of aminated fullerene,elucidates the molecular mechanism,and provides a new strategy for the antineoplastic drug development on functional fullerenes.
基金the Natural Science Foundation of Zhejiang Province(Nos.LR24B020003 and LQ24B020003)the National Natural Science Foundation of China(No.21921003)for financial support。
文摘Reported here is the synthesis of a new macrocycle bearing anionic carboxylate groups with water-soluble aggregation-induced emission(AIE).The water-soluble macrocycle without typical AIE luminogens is constructed based on the building block of benzothiadiazole.It exhibits a remarkable AIE effect.This watersoluble macrocycle can selectively bind different types of biogenic amines in aqueous media with the tightest binding towards spermine.The fluorescence enhancement induced by supramolecular encapsulation is used to detect spermine.
基金supported by the Shanghai Agricultural Science and Technology Program (2022-02-08-00-12-F01176)he National Natural Science Foundation of China (52006135)
文摘Direct air capture(DAC)of CO_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission technologies.Since large air flows are required to capture the ultradilute CO_(2)from the air,lab-synthesized adsorbents in powder form may cause unacceptable gas pressure drops and poor heat and mass transfer efficiencies.A structured adsorbent is essential for the implementation of gas-solid contactors for cost-and energy-efficient DAC systems.In this study,efficient adsorbent poly(ethyleneimine)(PEI)-functionalized Mg-Al-CO_(3)layered double hydroxide(LDH)-derived mixed metal oxides(MMOs)are three-dimensional(3D)printed into monoliths for the first time with more than 90%adsorbent loadings.The printing process has been optimized by initially printing the LDH powder into monoliths followed by calcination into MMO monoliths.This structure exhibits a 32.7%higher specific surface area and a 46.1%higher pore volume,as compared to the direct printing of the MMO powder into a monolith.After impregnation of PEI,the monolith demonstrates a large adsorption capacity(1.82 mmol/g)and fast kinetics(0.7 mmol/g/h)using a CO_(2)feed gas at 400 ppm at 25℃,one of the highest values among the shaped DAC adsorbents.Smearing of the amino-polymers during the post-printing process affects the diffusion of CO_(2),resulting in slower adsorption kinetics of pre-impregnation monoliths compared to post-impregnation monoliths.The optimal PEI/MeOH ratio for the post-impregnation solution prevents pores clogging that would affect both adsorption capacity and kinetics.
基金National Key Research and Development Program of China,Grant/Award Number:2022YFB3807700Hubei Natural Science Foundation Innovation Group Project,Grant/Award Number:2022CFA020+2 种基金Joint Funds of the Hubei Natural Science Foundation Innovation and Development,Grant/Award Number:2022CFD034Major Technological Innovation Project of Hubei Science and Technology Department,Grant/Award Number:2019AAA164National Natural Science Foundation of China,Grant/Award Number:2022CFD034。
文摘Fe-based Prussian blue(Fe-PB)cathode material shows great application potential in sodium(Na)-ion batteries due to its high theoretical capacity,long cycle life,low cost,and simple preparation process.However,the crystalline water and vacancies of Fe-PB lattice,the low electrical conductivity,and the dissolution of metal ions lead to limited capacity and poor cycling stability.In this work,a perylene tetracarboxylic dianhydride amine(PTCDA)coating layer is successfully fabricated on the surface of Fe-PB by a liquid-phase method.The aminated PTCDA(PTCA)coating not only increases the specific surface area and electronic conductivity but also effectively reduces the crystalline water and vacancies,which avoids the erosion of Fe-PB by electrolyte.Consequently,the PTCA layer reduces the charge transfer resistance,enhances the Na-ion diffusion coefficient,and improves the structure stability.The PTCA-coated Fe-PB exhibits superior Na storage performance with a first discharge capacity of 145.2 mAh g^(−1) at 100 mA g^(−1).Long cycling tests exhibit minimal capacity decay of 0.027%per cycle over 1000 cycles at 1 A g^(−1).Therefore,this PTCA coating strategy has shown promising competence in enhancing the electrochemical performance of Fe-PB,which can potentially serve as a universal electrode coating strategy for Na-ion batteries.
基金supported by the Major Science and Technology Project of Anhui Province(201903a07020004)the National Natural Science Foundation of China(22208078)the Fundamental Research Funds for the Central Universities(JZ2023HGTB0226).
文摘The effect of the presence of trace SO_(2)in industrial flue gas on the amine-scrubbing-based absorption process for CO_(2)capture has been a matter of concern.This study aimed to investigate the effect of trace SO_(2)on the CO_(2)capture process using piperazine-based amine absorbents,focusing on SO_(2)-resistance capability,SO_(2)/CO_(2)absorption selectivity,and cyclic stability.The presence of trace SO_(2)not only restrains CO_(2)absorption,but also promotes the formation of carbamate within the piperazine-based amine absorbents.Remarkably,the incorporation of aminoethyl group in piperazine-based amine absorbents can enhance the SO_(2)-resistance capability by promoting the formation of carbamate,while piperazine-based amine absorbents with hydroxyethyl group can promote the formation of bicarbonate to reduce the SO_(2)-resistance capability.The work offers valuable insights into the efficient application of novel amine absorbents for CO_(2)capture from practical industrial flue gas.
基金supported by National Natural Science Foundation of China(32022066,32101975)Zhejiang Province Natural Science Foundation(LQ22C200017)+1 种基金China Postdoctoral Foundation(2020M681806,2021T140348)Science and Technology Programs of Ningbo(202003N4130,202002N3067)。
文摘To deepen the understanding in the effect of potassium lactate on the sensory quality and safety of Rugao ham,sensory attributes,physicochemical parameters,total volatile basic nitrogen(TVBN),microorganism community and biogenic amines of Rugao ham manufactured with different potassium lactate levels(0%,0.5%,1%,2%)were investigated;the relationship between microbial community and the formation of TVBN and biogenic amines was further evaluated.With the increase of potassium lactate from 0%to 2%,the increased sensory scores and the decreased total aerobic bacterial count and TVBN were observed;the abundance of Staphylococcus increased,while the content of Halomonas decreased.LDA effect size(LEf Se)and correlations analysis showed that Staphylococcus equorum and Lactobacillus fermentum could be the key species to improve sensory scores and decrease biogenic amines and TVBN.Metabolic pathway analysis further showed that amino acids metabolism and nitrogen metabolism were mainly involved in decreasing TVBN and biogenic amines in the treatment of 2%potassium lactate.
基金supported by the Priority Academic Program Development of Jiangsu Higher Education Institution(PAPD).
文摘Lactic acid bacteria and coagulase-negative staphylococci play an important role in the production of fermented sausages,such as inhibiting the growth of undesirable bacteria and antioxidant.In this study,the effects of inoculation with different starter cultures(Lactiplantibacillus plantarum HN108 and Staphylococcus simulans NJ209)on the free amino acids(FAAs),biogenic amines(BAs)and volatile compounds of fermented sausages were investigated using an amino acid analyzer,ultra performance liquid chromatography and gas chromatography-ion mobility spectrometry,respectively.The pH and carbonyl content of the inoculated group was significantly lower than those in the control group(P<0.05).L.plantarum HN108 significantly reduced the content of FAAs and BAs in fermented sausage production(P<0.05),while S.simulans NJ209 promoted the formation of FAAs(especially bitter amino acids)and exhibited slight BAs-reducing activity.In addition,L.plantarum HN108 promoted the formation of volatile compounds such as ketones,alcohols and alkenes in sausages.In conclusion,L.plantarum HN108 could contribute to reducing the content of putrescine and tyramine and forming the desirable flavor compounds in fermented sausages.Thus,L.plantarum HN108 is expected to be a starter culture that can improve the safety and flavor of fermented sausages.