查找使用阿拉丁产品的科研文献

High efficient protocol for the modification of polyethersulfone membranes with anticoagulant and antifouling properties via in situ cross-linked copolymerization

Hui Qin,Chuangchao Sun,Chao He,Dongsheng Wang,Chong Cheng,Shengqiang Nie,Shudong Sun,Changsheng Zhao

In this paper, we provide a highly efficient, convenient and universal protocol for blood-compatible modification of polyethersulfone (PES) membranes via in situ cross-linked copolymerization of 2-hydroxyethl methacrylate (HEMA) and acrylic acid (AA) in PES solutions. Static water contact angle, protein adsorption, platelet adhesion, and clotting time of the modified PES membranes are systematically studied, and the results indicate that the modified membranes show improved hydrophilicity, good blood anticoagulant and antifouling properties after introducing HEMA and AA. Meanwhile, the modified membranes perform low contact activation and complement activation when they come in contact with blood. The effect of the HEMA/AA ratios on the blood compatibility is also investigated to identify the different roles played by HEMA and AA in the modification; the HEMA could more effectively enhance the membrane antifouling property, while the AA could more effectively improve the anticoagulant property. The results indicated that the blood-compatible PES membranes prepared via the in situ cross-linked copolymerization had potential to be used in the field of blood purification.

Trichoderma-secreted anthranilic acid promotes lateral root development via auxin signaling and RBOHF-induced endodermal cell wall remodeling

Yu Chen,Yansong Fu,Yanwei Xia,Youzhi Miao,Jiahui Shao,Wei Xuan,Yunpeng Liu,Weibing Xun,Qiuyan Yan,Qirong Shen,Ruifu Zhang

Trichoderma spp. have evolved the capacity to communicate with plants by producing various secondary metabolites (SMs). Nonhormonal SMs play important roles in plant root development, while specific SMs from rhizosphere microbes and their underlying mechanisms to control plant root branching are still largely unknown. In this study, a compound, anthranilic acid (2-AA), is identified from T. guizhouense NJAU4742 to promote lateral root development. Further studies demonstrate that 2-AA positively regulates auxin signaling and transport in the canonical auxin pathway. 2-AA also partly rescues the lateral root numbers of CASP1 pro :shy2-2 , which regulates endodermal cell wall remodeling via an RBOHF -induced reactive oxygen species burst. In addition, our work reports another role for microbial 2-AA in the regulation of lateral root development, which is different from its better-known role in plant indole-3-acetic acid biosynthesis. In summary, this study identifies 2-AA from T. guizhouense NJAU4742, which plays versatile roles in regulating plant root development.

Preparation and Characterization of Thermoresponsive Poly(N-isopropylacrylamide-co-acrylic acid)-Grafted Hollow Fe3O4/SiO2 Microspheres with Surface Holes for BSA Release

Jing Zhao,Ming Zeng,Kaiqiang Zheng,Xinhua He,Minqiang Xie,Xiaoyi Fu

Thermoresponsive P(NIPAM-AA)/Fe3O4/SiO2microspheres with surface holes serving as carriers were prepared using p-Fe3O4/SiO2microspheres with a thermoresponsive copolymer. The p-Fe3O4/SiO2microspheres was obtained using a modified Pickering method and chemical etching. The surface pore size of p-Fe3O4/SiO2microspheres was in the range of 18.3 nm~37.2 nm and the cavity size was approximately 60 nm, which are suitable for loading and transporting biological macromolecules. P(NIPAM-AA) was synthesized inside and outside of the p-Fe3O4/SiO2microspheres via atom transfer radical polymerization of NIPAM, MBA and AA. The volume phase transition temperature (VPTT) of the specifically designed P(NIPAM-AA)/Fe3O4/SiO2microspheres was 42.5 °C. The saturation magnetization of P(NIPAM-AA)/Fe3O4/SiO2microspheres was 72.7 emu/g. The P(NIPAM-AA)/Fe3O4/SiO2microspheres were used as carriers to study the loading and release behavior of BSA. This microsphere system shows potential for the loading of proteins as a drug delivery platform.Keywords:P(NIPAM-AA);Fe3O4/SiO2hollow microspheres;holes;drug release

Synthesis and Properties of AM-AA-SSS-DMCAAC16 Hydrophobic Associating Polymer

Jun Li,Yinliang Bao,Xiaojuan Tu,Yuedong Li,Xiaoping Qin,Cuixia Li,Song Qing

A hydrophobic associative polymer (AM-AA-SSS-DMCAAC 16 ) was synthesized using the aqueous polymerization method with acrylic acid (AA), acrylamide (AM), sodium styrene sulfonate (SSS), and hexadecyl dimethylallyl ammonium chloride (DMCAAC 16 ) as the main raw materials and ammonium persulfate sodium bisulfite as the initiator. The synthesis conditions for AM-AA-SSS-DMCAAC 16 are as follows: a total monomer mass concentration of 25%, an initiator dosage of 0.2% of the total monomer mass, a reaction temperature of 40°C, and a reaction time of 4 h. The structure of AM-AA-SSS-DMCAAC 16 was characterized by infrared spectroscopy, nuclear magnetic resonance hydrogen spectroscopy, and scanning electron microscopy. The viscosity enhancement, shear resistance, temperature resistance, salt resistance, and oil displacement performance of AM-AA-SSS-DMCAAC 16 were studied. The experimental results showed that the apparent viscosity of the 2000 mg/L AM-AA-SSS-DMCAAC 16 solution prepared with injected water at 25°C was significantly higher than that of the same concentration of acrylamide and acrylic acid binary copolymer (AM-AA) solution. The viscosity of a 2000 mg/L AM-AA-SSS-DMCAAC 16 solution prepared with a 5000 mg/L sodium ion solution is 247.27 mPa s, which is 137.34 mPa s higher than the same concentration of AM-AA solution. After mechanical shearing at 28,000 r/min for 30 s, the viscosity retention rate of the 2000 mg/L AM-AA-SSS-DMCAAC 16 solution was 11.99% higher than that of the same concentration AM-AA solution. Under the same experimental conditions, the enhanced oil recovery rates of AM-AA and AM-AA-SSS-DMCAAC 16 were 11.28% and 17.49%, respectively, and AM-AA-SSS-DMCAAC 16 showed good oil displacement ability.

Exploration of oligomeric sodium carboxylates as novel draw solutes for forward osmosis

Qingwu Long,Jiaqi Huang,Shu Xiong,Liang Shen,Yan Wang

FO technology has attracted growing attention in water treatment and desalination applications recently. The development of a suitable draw solute with high performance and low cost is therefore in high demand to facilitate practical FO applications. In this study, two oligomeric carboxylates — poly maleic acid sodium (PMAS) and poly(itaconate-co-acrylate) sodium [P(IA-co-AA)] with controllable molecular weights of 400–1000   Da, are synthesized via one-step polymerization and employed as novel draw solutes for FO applications. The successful synthesis is confirmed via by various characterization techniques. The osmotic pressure, relative viscosity and FO performance of PMAS and P(IA-co-AA) draw solutions with different concentrations are studied systematically. Two types of FO membranes are employed, and their performance is compared using PMAS draw solution. With 0.5   mol/kg PMAS draw solution and DI water feed solution, high water fluxes of 30.6 and 62.4   LMH can be achieved using HTI-TFC and homemade PSf-TFC membrane in the FO tests, respectively. 0.5   mol/kg PMAS draw solution is further studied for the desalination of 0.6   mol/kg NaCl solution via FO, with a water flux of 6.63   LMH obtained. The diluted PMAS solution after FO test can be recovered by nanofiltration with a high rejection rate. The excellent performance and available recovery route of the developed oligomeric carboxylates imply their great potential as promising draw solutes for FO applications.

Preparation of a phosphorous-free terpolymer as a decalcifying agent for removing calcium from crude oil

Shuaishuai Ma,Zhilan Cai,Yuming Zhou,Shiwei Li,Shuang Liang

A novel phosphorous-free terpolymer, used as a decalcifying agent for removing calcium from crude oil, was prepared through a free-radical polymerization reaction of acrylic acid (AA), allylpolyethoxy amino carboxylate (APEA), and 2-hydroxyethyl acrylate (HEA) in water with ammonium persulfate as initiator. The structure of the synthesized AA–APEA–HEA terpolymer was characterized by Fourier transform infrared spectrometry and 1H nuclear magnetic resonance (1H-NMR). AA–APEA–HEA was used to remove calcium from Luning pipeline crude oil. The effects of several factors, such as molar ratio, dosage, and reaction temperature on calcium removal efficiencies from crude oil were evaluated. The results indicated that the removal of calcium from crude oil using AA–APEA–HEA was far more efficient than that using AA–APEA, PAA, HPMA, and PESA under the same conditions. The optimum conditions for calcium removal from crude oils were as follows: (a) molar ratio of AA–APEA–HEA, 2 : 1 : 0.5; (b) dosage of AA–APEA–HEA, 100 ppm; (c) reaction temperature, 100 °C. Under these conditions, the removal efficiency of calcium from Luning pipeline crude oils was approximately 98.63%. Furthermore, the proposed decalcification mechanism suggests surface complexation and chelation between the carboxylic (–COO−) and amino (–NH2) functional groups and Ca2+, with the polyethylene glycol segments increasing its solubility in water and the lipophilic ester groups increasing its affinity to oil.

Improvement in the blood compatibility of polyvinylidene fluoride membranes via in situ cross-linking polymerization

Shengqiang Nie,Jiazhou Zeng,Hui Qin,Xiaolu Xu,Jia Zeng,Chunlin Yang,Jun Luo

In this study, we have provided a highly efficient, convenient, and universal protocol for preparing polyvinylidene fluoride (PVDF) membranes with low blood contact activation via in situ cross-linking copolymerization of 2-hydroxyethl methacrylate (HEMA) and acrylic acid (AA) in a solution of PVDF. The modified membranes were prepared from PVDF solution by phase inversion technology. The composition and morphology of the modified membranes were confirmed by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, thermogravimetric (TG) analysis, and scanning electron microscopy (SEM). Protein adsorption, clotting time, and contact activation on the modified PVDF membranes were systematically studied, the results indicating that after the incorporation of AA and HEMA, the modified PVDF membranes possessed anticoagulant properties in addition to low contact activation of blood components when in contact with blood. Therefore, fluorinated PVDF membranes with surfaces enriched with carboxyl and hydroxyl groups possessed the potential for use in long-term blood-contacting devices.

Basic rules of NO oxidation by Fe2+/H2O2/AA directional decomposition system

Haiqian Zhao,Xingcun Gao,Chenghao Liu,Zhonghua Wang,Hanbing Qi

Basic rules of NO oxidation by a Fe 2+ /H 2 O 2 /AA directional decomposition system were researched based on the technical background of flue gas NO x removal. Effects of gas-liquid interfacial area, main gas, and solution parameters on NO oxidation efficiency ( η ) were analyzed. The results showed that adequate contact area was the precondition for high η by a Fe 2+ /H 2 O 2 /AA system. η decreased with the increase in NO concentration, which illustrated that this method would be efficient in oxidizing NO at a low concentration. η tended to decrease linearly with the growth in gas flow, however, the NO oxidation rate ( v ) rose with the increase in NO concentration and gas flow. η increased with the initial concentrations of H 2 O 2 and Fe 2+ , but the amplitude decreased. Controlling the initial concentrations of H 2 O 2 and Fe 2+ to achieve reasonable synergies between generation rate and consumption rate of ·OH could weaken the invalid consumption of reactants. η increased with the increase in temperature in the range 30–60 °C, but it nearly did not change with temperature after 60 °C. This oxidation technology and the traditional wet flue gas desulphurization technology exhibited temperature synergy. Under typical pH of wet desulphurization, η and H 2 O 2 consumption rate did not change obviously.

Removal of methylene blue from aqueous solutions using Poly(AA-co-DVB)

Jia Du,Luanluan Zhang,Hejun Gao,Yunwen Liao

Effective Structure Control of Colloidal Molecules and the Morphology Evolution Mechanism Investigation

Wei Zhang,Hua Cheng,Rui Pan,Yi Gong,Zhengya Gan,Rui Hu,Jianjun Ding,Xian Zhang,Xingyou Tian

Colloidal molecules (CMs), nonspherical clusters of a small number of particles, can be used as building blocks for self-assembly applications. Here, we propose a novel one pot method for CMs synthesis. First, poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAM-co-AA)) microgels were prepared by soap-free emulsion polymerization as seed particles, then monomer styrene and cross-linking agent divinylbenzene (DVB) were added, which could be polymerized by the remaining free radicals on the seed surface in situ. P(NIPAM-co-AA)-PS colloidal molecules with a series of morphologies such as popcorn-like, CO2-like, NH3-like, CH4-like and so on could be obtained. The effects of satellite colloid viscosity, interfacial tension, and polymer chain mobility on the number of satellite colloid have been investigated, and the formation mechanism of CMs is proposed based on morphology evolution investigation. Compared with the existing CM synthesis techniques, our method enables fabricating CMs from vinyl monomer in a facile and efficient way, and the scientific finding regarding the CMs formation will guide the CMs fabrication toward salable and reliable direction.

Fabrication and Characterization of Cotton Fabrics with Grafted Thermo-Responsive Random Copolymer Poly(2-(2-methoxyethoxy) Ethoxyethyl Methacrylate-co-Acrylic Acid)

Yang Yi Chen,Qi Zhong,Tao Chen,Ji Ping Wang

The cotton fabrics with enhanced cleaning capability were prepared by grafting thermo-responsive random copolymer poly (2-(2-methoxyethoxy) ethoxyethyl methacrylate-co-acrylic acid), abbreviated as P(MEO2MA-co-AA), to the amino modified cotton fabrics. ATR-FTIR measurement confirmed the immobilization of P(MEO2MA-co-AA) to the cotton fabrics. Equilibrium swelling ratio indicates that the cotton fabric with grafted P(MEO2MA-co-AA) possesses thermo-responsive ability .The enhanced cleaning capability was investigated by the decontamination experiments probed with confocal microscope. The results show the cleaning capability can be prominently improved when the cleaning temperature is lower than the LCST of P(MEO2MA-co-AA).

Swelling Behavior and Adsorption Properties of Multicomponent PF127DA/P (AA-AM)/PVA Hydrogel

Zhi-Ke Wang,BaoFen Sun,Ting-Ting Li

In this study, an adsorbent capable of rapidly adsorbing heavy metal ions was prepared using PVA crosslinked with PF127DA and AA/AM. The swelling behavior of the hydrogel in salt solutions was investigated based on the Flory–Huggins theory model. The results indicated that the theoretical predictions of the hydrogel's volume swelling ratio, derived from the Flory–Rehner swelling theory and the Donnan equilibrium, were in agreement with the experimental swelling data of the hydrogel in water and salt solutions. With the increase in the amount of crosslinking agent PF127DA, the water absorption swelling ratio of the composite material was reduced by half, with the volume swelling ratio decreasing from 3.56 to 2.33. When the concentration of cations in the salt solution increased from 10 −5 mol/L to 10 −1 mol/L, the volume swelling ratio of the hydrogel showed a decreasing trend, which in turn affected the adsorption performance of the pollutant. Therefore, increasing the amount of crosslinking agent can enhance the colloidal strength, provided that its swelling properties are not compromised. Additionally, the presence of high concentrations of salt can affect the adsorption behavior of the hydrogel, and appropriate measures should be taken in practical applications to avoid its impact on adsorption behavior. Graphical The study prepared adsorbent, analyzed PF127DA's effect on hydrogel, and found it affects swelling and has high Pb adsorption capacity for heavy metal removal.