SEPARATION AND PURIFICATION TECHNOLOGY
·
2018
·
IF 3.927
Cui Wang,Qiangqiang Yang,Zhenhong Li,Kun-Yi Andrew Lin,Shaoping Tong
A magnetic carbon-coated Fe-C/N composite was synthesized by a simple impregnation method and its performance in activating persulfate (PS) to degrade Acid Red 73 (AR 73) was investigated. The as-prepared carbon-coated Fe-C/N hybrid material was characterized via transmission electron microscopy , Raman spectra, X-ray diffraction and X-ray photoelectron spectrum. Degradation experiments showed that 98.11% of AR 73 could be degraded in 10 min, but its COD was partly removed. The effects of initial reaction pH and temperature were also evaluated. An increase of temperature was beneficial for the removal of AR 73, while the increase of pH had an opposite result. The activation energy of the AR 73 degradation was determined to be 46.12 KJ/mol, smaller than those in relative literatures. The recycling test showed that the carbon-coated Fe-C/N composite had good stability. The mechanism study indicated that the catalytic performance of Fe-C/N was due to the synergistic effect between Fe 3 C and Fe 3 N, and the N doped carbon shell suppressed the rate of Fe leaching, thus enhancing its stability.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2018
·Vol. 9
·期 2
·286-301
·
IF 5.365
Mengyuan Zhang,Shipeng Wu,Longchun Bian,Qiue Cao,Wenhao Fang
Ce–Ni mixed oxides with different Ni/Ce molar ratios, promoted by a rather low amount of Pd (0.2 wt%), were prepared by a simple one-pot precipitation method. The thus-synthesized CeNiXOY and Pd–CeNiXOY catalysts were applied respectively to the direct N-alkylation of amine and alcohol via oxidative coupling, under O2 in the absence of basic additives. The CeNiXOY catalyst could provide a >99% yield of imine in the model alkylation reaction of aniline with benzyl alcohol at 100 °C. The Pd-promoted Pd–CeNiXOY catalyst surprisingly showed an enhanced imine yield (>99%) at a mild temperature of 60 °C. This catalyst exhibited good reusability, and moreover, demonstrated high performance towards imine synthesis from various amines with alcohols. The presence of Pd species and the Ni/Ce molar ratio showed a synergistic impact on the conversion of aniline, as well as on the product selectivity, which was believed to be related to the improvement on the intrinsic activity of the oxidation of benzyl alcohol to benzaldehyde. Various physicochemical techniques, including ICP-MS, XRD, N2 adsorption–desorption, UV-Raman, H2-TPR, TEM, EPMA and XPS, were employed to study mainly the composition, structure and redox properties of the catalysts. The proportion of Ce3+ species and oxygen vacancies, which can be manipulated by the Ce–Ni redox system and the interaction between Ce and Ni, was crucial to the selective activation of alcohols in the presence of reactive amines. The activation of alcohol on the highly reactive Pd0 species was the other crucial factor.
研究领域:
催化化学
·
材料科学
·
绿色化学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2020
·
IF 3.421
Cheng Yang,Chengyong Shu,Zhuofan Gan,Chen Lai,Jijun Ma,Wei Tang,Yuping Wu
ZIF-8-derived Fe–N–S triple doping hollow-shell nanoparticles are prepared by the surface modification of SCN– ligands. Fe3+ ions are highly adsorbed on the SCN–-modified layer, forming a hollow-shell rhombic dodecahedron particle after pyrolysis. Doping extra S atom is found to be an effective method to increase the density of atomically dispersed active sites and boost their catalytic performance. The H-ZIF-Fe-SCN catalyst shows good bifunctional stability toward the oxygen reduction reaction and the oxygen evolution reaction in alkaline solution, the half-wave potential for the H-ZIF-Fe-SCN catalyst was recorded to be 0.889 V vs reverse hydrogen electrode, and a maximum power performance of 158.8 mW cm–2 was achieved when it was used as a cathode catalyst in zinc–air batteries.
研究领域:
材料科学
·
电化学
·
能源存储与转换
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2013
·
IF 4.187
Xiu-Juan Shi,Gao-Jian Chen,Yan-Wei Wang,Lin Yuan,Qiang Zhang,David M. Haddleton,Hong Chen
Surface-initiated SET-LRP was used to synthesize polymer brush containing N-isopropylacrylamide and adamantyl acrylate using Cu(I)Cl/Me6-TREN as precursor catalyst and isopropanol/H2O as solvent. Different reaction conditions were explored to investigate the influence of different parameters (reaction time, catalyst concentration, monomer concentration) on the polymerization. Copolymers with variable 1-adamantan-1-ylmethyl acrylate (Ada) content and comparable thickness were synthesized onto silicon surfaces. Furthermore, the hydrophilic and bioactive molecule β-cyclodextrin-(mannose)7 (CDm) was synthesized and complexed with adamantane via host–guest interaction. The effect of adamantane alone and the effect of CDm together with adamantane on the wettability and thermoresponsive property of surface were investigated in detail. Experimental and molecular structure analysis showed that Ada at certain content together with CDm has the greatest impact on surface wettability. When Ada content was high (20%), copolymer–CDm surfaces showed almost no CDm complexed with Ada as the result of steric hindrance.
研究领域:
材料科学
·
生物医学工程
·
高分子化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2022
·
IF 10.319
Caiyan Gao,Xuezhen Feng,Lian Yi,Xiaoyong Wu,Renji Zheng,Gaoke Zhang,Yubiao Li
Formaldehyde (FA), as an important chemical raw material, has been widely used in many fields. However, the discharge of a large amount of FA-containing wastewater poses a serious threat to the environment and human health. Recently, the in-situ hydrogen energy release technology of hydrogen-containing stable liquid has been extensively explored due to its safe storage. Exploring a robust method to achieve FA removal and synchronous in-situ hydrogen release from FA containing wastewater is of great significant for environmental protection and energy crisis alleviation. Here, we have innovatively introduced peroxymonosulfate (PMS) activation technology into FA removal and hydrogen production simultaneously. The composite of nitrogen doped carbon coating Co 9 S 8 nanotubes (Co 9 S 8 @N−C) is employed as a proof of concept for FA decomposition and simultaneously hydrogen production based on PMS activation system. As expected, the Co 9 S 8 @N−C/PMS system presents much superior hydrogen production efficiency and satisfactory FA removal rate towards FA wastewater than those of common catalysis, photocatalysis and Fenton reaction in the basic condition in a wide range of FA concentration. The hydrogen yield reaches a value as high as 471 μmol within 60 min, corresponding to a FA degradation rate of 30% with an initial FA concentration of 0.722 mol L −1 . Characterizations and density functional theory (DFT) calculations suggest that the free radical process dominated by superoxide radical (O 2 ⋅ − ) and nonradical process dominated by singlet oxygen ( 1 O 2 ), which are induced by Co 9 S 8 @N−C/PMS system, are responsible for highly efficient hydrogen production via FA degradation. These generated O 2 ⋅ − and 1 O 2 can extract ⋅ H from FA to form ⋅ OOH intermediate, which can further combine with the ⋅ H from water to produce hydrogen. This study provides an applicable technique for environmental purification and new energy development based on FA containing wastewater.
研究领域:
环境科学
·
化学工程
·
能源技术
·
水处理
✓ 已验证
DOI
高影响因子
Polymer Chemistry
·
2013
·Vol. 5
·期 3
·761-770
·
IF 5.231
Wenlong Li,Peiyi Wu
The influence of different Ionic Liquids (ILs) on the phase transition behavior of poly(N-vinylcaprolactam) (PVCL) solution is investigated by differential scanning calorimetry (DSC) and turbidity measurements, in combination with FT-IR spectroscopy. The DSC and turbidity results reveal that hydrophilic ILs at a concentration of 0.25 mol L−1 only slightly change the transition temperature. The LCST experiences an increase while the phase separation behavior disappears gradually as the concentration of 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) increases from 0 to 1.0 mol L−1. In contrast, the addition of hydrophobic ILs, especially 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([EMIM][NTf2]), even at a low concentration, greatly raises the LCST, indicating the possibility of hydrogen bonding between [EMIM][NTf2] and PVCL. Finally, temperature-dependent FTIR spectra are employed to elucidate the dynamic mechanism of the different influences on the phase transition of PVCL. The hydrophilic ILs can change the state of the PVCL chains indirectly by varying their interaction with water molecules. For comparison, the formation of hydrogen bonds between the unsaturated C–H of [EMIM][NTf2] and the CO of PVCL results in a higher temperature and more energy to complete the phase transition. However, with the continual increasing of the concentration, extra [EMIM][NTf2] can not be well dispersed in water due to its hydrophobicity, so the LCST undergoes a decrease and finally reaches an equilibrium. Additionally, hydrophilic ILs tend to distribute in the solution, while hydrophobic ILs, especially [EMIM][NTf2], are prone to be wrapped in polymer chains of the aggregates after phase separation. Furthermore, both types of IL experience the process of hydrogen bond disruption and chain aggregation.
研究领域:
高分子化学
·
物理化学
·
热力学
·
药物递送系统
·
刺激响应材料
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2023
·
IF 6.6
Ao Zhou,Hao Yu,Jun Tang,Biao Zhang,Fugang Qi,Yun Zhou,Nie Zhao,Xiaoping Ouyang
With the rapid development of the modern industrial marine economy, metal corrosion and biological fouling of marine ships and engineering equipment have become the main problems affecting the development of the marine industry. Traditional single-function coatings have only anti-corrosion or anti-fouling properties, which cannot meet the current needs of marine industry development for coating protection. In this study, a self-healing coating with good anticorrosion and antifouling properties has been prepared upon functionalization of a film forming resin and modification of a nanofiller. Initially, a modified acrylic resin (PAZ/N-PMI) was successfully synthesized by inserting zinc ions and a structural functional monomer ( N -phenyl maleimide; N-PMI) into the polymer chain of an acrylic resin using free radical solution polymerization . A fluorinated silica coated hydroxylated multi-walled carbon nanotubes nanocomposite (F-MWCNTs-OH@SiO 2 ) was dispersed in PAZ/N-PMI resin to prepare the composite coating samples. The composite coating showed good performance, in which the antibacterial rate of the composite coating against Staphylococcus aureus and Escherichia coli was >99.98 %. When F-MWCNTs-OH@SiO 2 was 3 wt%, the Z f=0.01Hz of the composite coating reached the highest value, which was 3 orders of magnitude higher than that of the PAZ/N-PMI coating. At the same time, the prepared composite coating also exhibited good self-healing properties. This study provides a broad application prospect for the development of high quality marine anti-corrosion and anti-fouling organic coatings .
研究领域:
材料科学
·
海洋工程
·
防腐与防污技术
✓ 已验证
DOI
高影响因子
Science China-Chemistry
·
2022
·Vol. 66
·期 2
·548-561
·
IF 10.138
Zhao Ying-Han,Li Wenhao,Shen Tao,Zhao Yan,Liu Yunqi,Wang Yang
The development of readily accessible high-mobility n-type semiconducting polymers is in great demand for realizing high-performance p-n junction-based organic electronics. In this study, we demonstrate that with the combination of dual-acceptor strategy and C-H direct arylation polymerization (DArP), unipolar n-type semiconducting polymers can be conveniently synthesized. By tuning the monomer concentration, three dual-acceptor polymers, namely, poly(naphthalene diimide- alt -dithiophenyl pyrrolopyrrole-dione) (PNDI-DPP), poly(naphthalene diimide- alt -dithiophenyl isoindigo) (PNDI-IID), and poly (naphthalene diimide- alt -dithiophenyl bezothiadiazole) (PNDI-BT) can be obtained via C-H activation with decent number average molecular weight of ∼10 to 30 kg mol −1 and relatively narrow polydispersity index of ∼2. In addition, these polymers are defect-free in nature as evidenced by the nuclear magnetic resonance. Moreover, we attribute the different molar masses of the three copolymers under the same DArP condition to the different α-C-H acidity, which may stem from different electron-withdrawing capability of the hydrogenated acceptor units. Furthermore, the influence of the hydrogenated acceptor monomers on the optical, electrochemical and charge transporting properties is comprehensively studied. Among the three dual-acceptor polymers, PNDI-BT demonstrates the highest electron mobilities of up to 0.6 cm 2 V −1 s −1 in unipolar n-type organic transistors because of its relatively planar backbone, larger overlaps of the lowest unoccupied molecular orbital and strong H-aggregation. Note that the transistor performance of PNDI-BT synthesized via C-H activation in this study is at least comparable to the one made by conventional C(sp 2 )-C(sp 2 ) Stille or Suzuki cross-coupling polymerization. This study demonstrates the presented protocol can be a useful platform for sustainable and convenient synthesis of high-performance n-type semiconducting polymers.
研究领域:
材料科学
·
有机电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2024
·
IF 5.7
Yong Wang,Ziyuan Wang,Huifen Yu,Haidong Teng,Jianping Wu,Jiaqi Xu,Lirong Yang
Lipase from Rhizopus oryzae (ROL) exhibits remarkable sn-1,3 stereoselectivity and catalytic activity, but its poor thermostability limits its applications in the production of 1,3-dioleoyl-2-palmitoyl glycerol (OPO, a high-quality substitute for human milk fat). In this work, a semirational method was proposed to engineer the thermostability and catalytic activity of 4M (ROL mutant in our previous study). First, a computer-aided design is performed using 4M as a template, and N-glycosylation mutants are then recombinantly expressed and screened in Pichia pastoris, the optimal mutant N227 exhibited a half-life of 298.8 h at 45 °C, which is 7.23-folds longer than that of 4M. Its catalytic activity also reached 1043.80 ± 61.98 U/mg, representing a 29.2% increase compared to 4M (808.02 ± 47.02 U/mg). Molecular dynamics simulations of N227 suggested that the introduction of glycan enhanced the protein rigidity, while the strong hydrogen bonds formed between the glycan and the protein stabilized the lipase structure, thereby improving its thermostability. The acidolysis reaction between oleic acid (OA) and glycerol tripalmitate (PPP) was successfully carried out using immobilized N227, achieving a molar conversion rate of 90.2% for PPP. This engineering strategy guides the modification of lipases, while the glycomutants obtained in this study have potential applications in the biosynthesis of OPO.
研究领域:
生物技术
·
酶学
·
蛋白质工程
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
Polymer Chemistry
·
2013
·Vol. 4
·期 12
·3545-3553
·
IF 5.231
Yuan-Jia Pan,Dian Li,Sha Jin,Chuan Wei,Ke-Yi Wu,Jia Guo,Chang-Chun Wang
Folate-conjugated poly(N-(2-hydroxypropyl)methacrylamide-co-methacrylic acid) nanohydrogels were facilely prepared via distillation–precipitation polymerization and subsequent folate modification. Due to the nanohydrogels being crosslinked with disulphide bonds, they could be easily degraded into short polymer chains in the presence of glutathione, which will be beneficial for easily discharging the nanohydrogels from the body. Doxorubicin (DOX), a clinical anti-cancer drug, was efficiently loaded in the nanohydrogels (up to 39.3 wt%) by the electrostatic interactions between the amine group in doxorubicin (DOX) and the carboxyl groups in the nanohydrogels at neutral conditions. The cumulative release profile of the DOX-loaded nanohydrogels showed a relatively low level of drug release (23 wt% in 48 h) at pH 7.4 and a quick release (over 95 wt% in 2 h) at pH 5.0 with reducing environment, exhibiting pH/redox dual-stimuli-responsive drug release. The dose-dependent cytotoxicity of the drug-loaded nanohydrogels was studied by the CCK-8 assay. The nanohydrogels possess many favourable merits of drug carriers, such as excellent biocompatibility, high drug loading capacity, minimal drug release under an extracellular condition, rapid drug release in response to the intracellular level of pH and reducing environment, and folate-mediated endocytosis, which endow them as great candidates for targeted delivery of anti-cancer drugs.
研究领域:
药剂学
·
生物材料学
·
肿瘤学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Yachao Wang,Yi Li,Qinglei Zhang,Xiangui Shang,Dongdong Yang,Ran Shi,Junqiang Zhao,Luqing Zhang,Yiping Zhao,Li Chen
Developing anti-fouling loose nanofiltration membranes (LNMs) that can achieve dye desalination of saline textile wastewater through dye retention and salt permeation for resource utilization remains an urgent challenge that needs to be addressed. Inspired by the biomimetic adhesion of mussels and the excellent fouling resistance of saltwater fish surfaces, novel LNMs were prepared through co-deposition strategy using dopamine (DA) and N -oxide zwitterionic polyethyleneimine (ZPEI) as biomimetic functional materials. There are multiple interactions between them, including Schiff base reaction, Michael addition reaction, cation-π interaction and covalent polymerization. Compared with PEI-LNM prepared under the similar method, the optimized ZPEI-LNM displays more uniform surface, smaller average roughness (6 nm vs 22 nm), and denser pore size (0.69 nm vs 0.79 nm), indicating the zwitterionic N -oxide moieties in ZPEI regulate the deposition process and the cross-linking structure of the selective layer. ZPEI-LNM exhibits a high pure water flux of 203.0 L m −2 h −1 under 0.6 MPa. Importantly, ZPEI-LNM shows high retention towards different dyes, including Congo red (CR, negative, 696.8 g/mol) of 100.0 %, Acid fuchsin (AF, negative, 585.5 g/mol) of 99.5 %, Crystalline violet (CV, positive, 408.0 g/mol) of 98.2 %, and Indigo carmine (negative, 466.4 g/mol) of 96.0 %, while the rejection of NaCl (8.7 %) and Na 2 SO 4 (12.7 %) are both lower. As expected, for the mixture solution of AF/NaCl, the dyes are efficiently rejected, while salts can pass through, indicating that ZPEI-LNM displays an excellent dye desalination capability. Furthermore, multiple-cycle antifouling tests for bovine serum albumin (BSA) and sodium alginate (SA) reveal that the flux recovery ratios are higher than those of PEI-LNM (BSA: 90.4 % vs 81.9 %; SA: 86.6 % vs 80.5 %), indicating ZPEI-LNM exhibits better anti-fouling performance towards different model foulants owing to the outstanding hydration layer caused by zwitterionic N -oxide moieties and lower surface roughness. Consequently, the work offers a new viewpoint for the fabrication of anti-fouling LNMs via biomimetic strategy for dye desalination.
研究领域:
材料科学
·
环境工程
·
生物仿生学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2019
·
IF 3.131
Hui Zhao,Ying Li
Tremella polysaccharide , a novel polysaccharide , not only has good ability of film forming, but also has excellent physiological functions, which was suitable to be used to prepare eco-friendly hydrogels. In this study, a novel pH/temperature responsive micelle-laden hydrogel based on tremella polysaccharide (WSK), carboxymethyl cellulose (CMC) and nonionic surfactant-decyl polyglucoside (C 10 APG) was fabricated through radical polymerization by crosslinking N-isopropylacrylamide (NIPAM), for the purpose to achieve controlled release of hydrophobic drugs indomethacin (IND). Firstly, WSK/CMC/PNIPAM hydrogels were prepared and their characteristics were investigated by FTIR, TGA , SEM, rheological and compressive tests as well as swelling experiments. Then the hydrophobic drug IND molecules were solubilized in C 10 APG micelles which were uniformly dispersed in the WSK/CMC/PNIPAM/C 10 APG networks. Lastly, the IND release behavior of WSK/CMC/PNIPAM/C 10 APG hydrogels was studied, which exhibited both pH and temperature sensitivity. The obtained WSK/C 10 APG-based pH/temperature sensitive hydrogel may have potential in biomedical applications such as drug vehicles and tissue engineering.
研究领域:
材料科学
·
药学
·
生物医学工程
·
高分子化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）