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Surface modification techniques of membranes to improve their antifouling characteristics: recent advancements

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 1837-1865 doi: 10.1007/s11705-023-2347-3

摘要: Surface modification techniques of membranes to improve their antifouling characteristics: recent advancements and developments

关键词: Surface modification techniques    

Tribological study on the surface modification of metal-on-polymer bioimplants

《机械工程前沿(英文)》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0682-6

摘要: The tribological performance of artificial joints is regarded as the main factor of the lifespan of implanted prostheses. The relationship between surface roughness and coefficient of friction (COF) under dry and lubricated conditions is studied. Results show that under dry test, friction coefficient is not reduced all the time with a decrease in surface roughness. On the contrary, a threshold of roughness value is observed, and frictional force increases again below this value. This critical value lies between 40 and 100 nm in Sa (roughness). This phenomenon is due to the transfer of friction mechanisms from abrasion to adhesion. Under wet test, COF always decreases with reduction in surface roughness. This result is mainly attributed to the existence of a thin layer of lubricant film that prevents the intimate contact of two articulating surfaces, thus greatly alleviating adhesion friction. Furthermore, surface texturing technology is successful in improving the corresponding tribological performance by decreasing friction force and mitigating surface deterioration. The even-distribution mode of texturing patterns is most suitable for artificial joints. By obtaining the optimal surface roughness and applying texturing technology, the tribological performance of polymer-based bioimplants can be greatly enhanced.

关键词: artificial joints     surface roughness     friction     surface texturing    

Improved blending strategy for membrane modification by virtue of surface segregation using surface-tailored

Shuai Liang, Peng Gao, Xiaoqi Gao, Kang Xiao, Xia Huang

《环境科学与工程前沿(英文)》 2016年 第10卷 第6期 doi: 10.1007/s11783-016-0875-5

摘要: Two types of amphiphilic nanoparticles were prepared via silanization reaction. Amphiphilic nanoparticles tend to protrude from membrane matrix by segregation. Blending with amphiphilic nanoparticles further enhances membrane hydrophilicity. Excessive silanization cause adverse effect on blending efficiency. Membrane modification is one of the most feasible and effective solutions to membrane fouling problem which tenaciously hampered the further augmentation of membrane separation technology. Blending modification with nanoparticles (NPs), owing to the convenience of being incorporated in established membrane production lines, possesses an advantageous viability in practical applications. However, the existing blending strategy suffers from a low utilization efficiency due to NP encasement by membrane matrix. The current study proposed an improved blending modification approach with amphiphilic NPs (aNPs), which were prepared through silanization using 3-(Trimethoxysilyl)propyl methacrylate (TMSPMA) as coupling agents and ZnO or SiO as pristine NPs (pNPs), respectively. The Fourier transform infrared and X-ray photoelectron spectroscopy analyses revealed the presence of appropriate organic components in both the ZnO and SiO aNPs, which verified the success of the silanization process. As compared with the pristine and conventional pNP-blended membranes, both the ZnO aNP-blended and SiO aNP-blended membranes with proper silanization (100% and 200% w/w) achieved a significantly increased blending efficiency with more NPs scattering on the internal and external membrane surfaces under scanning electron microscope observation. This improvement contributed to the increase of membrane hydrophilicity. Nevertheless, an extra dosage of the TMSPMA led to an encasement of NPs, thereby adversely affecting the properties of the resultant membranes. On the basis of all the tests, 100% (w/w) was selected as the optimum TMSPMA dosage for blending modification for both the ZnO and SiO types.

关键词: Membrane modification     Nanoparticle     Hydrophilic     Amphiphilic     Blending    

Feasibility of bubble surface modification for natural organic matter removal from river water using

Yulong Shi, Jiaxuan Yang, Jun Ma, Congwei Luo

《环境科学与工程前沿(英文)》 2017年 第11卷 第6期 doi: 10.1007/s11783-017-0954-2

摘要: A novel, functionalized bubble surface can be obtained in dissolved air flotation (DAF) by dosing chemicals in the saturator. In this study, different cationic chemicals were used as bubble surface modifiers, and their effects on natural organic matter (NOM) removal from river water were investigated. NOM in the samples was fractionated based on molecular weight and hydrophobicity. The disinfection byproduct formation potentials of each fraction and their removal efficiencies were also evaluated. The results showed that chitosan was the most promising bubble modifier compared with a surfactant and a synthetic polymer. Tiny bubbles in the DAF pump system facilitated the adsorption of chitosan onto microbubble surfaces. The hydrophobic NOM fraction was preferentially removed by chitosan-modified bubbles. Decreasing the recycle water pH from 7.0 to 5.5 improved the removal of hydrophilic NOM with low molecular weight. Likewise, hydrophilic organic compounds gave high dihaloacetic acid yields in raw water. An enhanced reduction of haloacetic acid precursors was obtained with recycle water at pH values of 5.5 and 4.0. The experimental results indicate that NOM fractions may interact with bubbles through different mechanisms. Positive bubble modification provides an alternative approach for DAF to enhance NOM removal.

关键词: Bubble surface modification     Chitosan     Disinfection by-product     Dissolved air flotation     Organic fraction    

Surface modification by ligand growth strategy for dense copper bismuth film as photocathode to enhance

《能源前沿(英文)》 doi: 10.1007/s11708-023-0893-5

摘要: Hydrogen production from photoelectrochemical (PEC) water splitting has been regarded as a promising way to utilize renewable and endless solar energy. However, semiconductor film grown on photoelectrode suffers from numerous challenges, leading to the poor PEC performance. Herein, a straightforward sol-gel method with the ligand-induced growth strategy was employed to obtain dense and homogeneous copper bismuthate photocathodes for PEC hydrogen evolution reaction. By various characterizations, it was found that the nucleation and surface growth of CuBi2O4 layer induced by 2-methoxyethanol ligand (2-CuBi2O4) demonstrated a decent crystallinity and coverage, as well as a large grain size and a low oxygen vacancy concentration, leading to the good ability of light absorption and carrier migration. Consequently, under simulated sunlight irradiation (AM1.5G, 100 mW/cm2), the 2-CuBi2O4 photocathode achieved an enhanced photocurrent density of −1.34 mA·cm−2 at 0.4 V versus the reversible hydrogen electrode and a promising applied bias photon-to-current efficiency of 0.586%. This surface modification by ligand growth strategy will shed light on the future design of advanced photoelectrodes for PEC water splitting.

关键词: copper bismuthate     photocathode     ligand growth strategy     dense film     PEC    

Surface modification of cellulose nanocrystals

WANG Neng, DING Enyong, CHENG Rongshi

《化学科学与工程前沿(英文)》 2007年 第1卷 第3期   页码 228-232 doi: 10.1007/s11705-007-0041-5

摘要: In order to improve the dispersibility of cellulose nanocrystal (CNC) particles, three different grafted reactions of acetylation, hydroxyethylation and hydroxypropylation were introduced to modify the CNC surface. The main advantages of these methods were the simple and easily controlled reaction conditions, and the dispersibility of the resulting products was distinctly improved. The properties of the modified CNC were characterized by means of Fourier transform infrared spectroscopy (FT-IR), C nuclear magnetic resonance (NMR), transmission electron microscopy (TEM) and thermogravimetric analyses (TGA). The results indicated that after desiccation, the modification products could be dispersed again in the proper solvents by ultrasonic treatments, and the diameter of their particles had no obvious changes. However, their thermal degradation behaviors were quite different. The initial decomposition temperature of the modified products via hydroxyethylation or hydroxypropylation was lower than that of modified products via acetylation.

关键词: acetylation     degradation     transform     microscopy     desiccation    

激光表面改性技术发展研究

张群莉,王梁,梅雪松,姚建华

《中国工程科学》 2020年 第22卷 第3期   页码 71-77 doi: 10.15302/J-SSCAE-2020.03.010

摘要:

激光表面改性技术利用高能量密度的激光束对零部件局部易损易耗区域进行快速处理,获得材料表面所需性能,进而大幅延长零部件使用寿命,已在航空航天、石油化工、能源、交通、冶金等领域获得应用。本文针对激光冲击强化、激光淬火、激光熔覆3 种典型的激光表面改性技术,梳理了相应技术特点及国内外应用现状,凝练我国相关技术领域面临的差距与问题,总结激光表面改性技术的重点发展方向:专用合金材料制备、多能场激光复合表面改性、面向现场的激光再制造、激光冲击强化控形控性、激光表面改性智能化、激光表面微结构化。从政府引导、国产化创新、产业链完善、质量评价标准体系、人才培养等方面提出发展建议,以期为我国激光表面改性技术发展提供参考借鉴。

关键词: 激光表面改性     冲击强化     淬火     熔覆     发展趋势    

Modification of polycarbonateurethane surface with poly(ethylene glycol) monoacrylate and phosphorylcholine

Jing YANG,Juan LV,Bin GAO,Li ZHANG,Dazhi YANG,Changcan SHI,Jintang GUO,Wenzhong LI,Yakai FENG

《化学科学与工程前沿(英文)》 2014年 第8卷 第2期   页码 188-196 doi: 10.1007/s11705-014-1414-1

摘要: Poly(ethylene glycol) monoacrylate (PEGMA) is grafted onto polycarbonateurethane (PCU) surface via ultraviolet initiated photopolymerization. The hydroxyl groups of poly(PEGMA) on the surface react with one NCO group of isophorone diisocyanate (IPDI) and another NCO group of IPDI is then hydrolyzed to form amino terminal group, which is further grafted with phosphorylcholine glyceraldehyde to establish a biocompatible hydrophilic structure on the surface. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirm the successful grafting of both PEG and phosphorylcholine functional groups on the surface. The decrease of the water contact angle for the modified film is caused by synergic effect of PEG and phosphorylcholine, which both have the high hydrophilicity. Furthermore, the number of platelets adhered is relative low on the synergetically modified PCU film compared with the PCU film modified only by poly(PEGMA). Our synergic modification method using both PEG and phosphorylcholine may be applied in surface modification of blood-contacting biomaterials and some relevant devices.

关键词: poly(ethylene glycol) monoacrylate     phosphorylcholine     polycarbonateurethane     surface modification     anti-platelet adhesion     biomaterials    

Surface modification of biomaterials by photochemical immobilization and photograft polymerization to

Yakai FENG, Haiyang ZHAO, Li ZHANG, Jintang GUO,

《化学科学与工程前沿(英文)》 2010年 第4卷 第3期   页码 372-381 doi: 10.1007/s11705-010-0005-z

摘要: Thrombus formation and blood coagulation are serious problems associated with blood contacting products, such as catheters, vascular grafts, artificial hearts, and heart valves. Recent progresses and strategies to improve the hemocompatibility of biomaterials by surface modification using photochemical immobilization and photograft polymerization are reviewed in this paper. Three approaches to modify biomaterial surfaces for improving the hemocompatibility, i.e., bioinert surfaces, immobilization of anticoagulative substances and biomimetic surfaces, are introduced. The biomimetic amphiphilic phosphorylcholine and Arg-Gly-Asp (RGD) sequence are the most effective and most often employed biomolecules and peptide sequence for improving hemocompatibility of material surfaces. The RGD sequence can enhance adhesion and growth of endothelial cells (ECs) on material surfaces and increase the retention of ECs under flow shear stress conditions. This surface modification is a promising strategy for biomaterials especially for cardiovascular grafts and functional tissue engineered blood vessels.

关键词: biomimetic amphiphilic     amphiphilic phosphorylcholine     endothelial     functional     biomaterial    

Surface modification of titanium dioxide for electrophoretic particles

PENG Xuhui, LE Yuan, BIAN Shuguang, LI Woyuan, WU Wei, DAI Haitao, CHEN Jianfeng

《化学科学与工程前沿(英文)》 2007年 第1卷 第4期   页码 338-342 doi: 10.1007/s11705-007-0061-1

摘要: To prepare stable electrophoretic ink (E Ink) needs color particles to be uniformly dispersed in the organic medium. Thus, t-he modification of inorganic particle surface is required. In this paper, Titanium dioxide modified by alumina has been studied. The surface composition and structures of modified particles have been characterized by X-ray photoelectron spectrometer (XPS), X-ray diffractometer (XRD) and Fourier transform infrared spectrometer (FT-IR). The dispersibility and electrophoretic mobility of these particles in tetrachloroethylene (TCE) have been investigated by laser particle size analyzer, static sedimentation and electrophoretic instrument. Effects of temperature, pH value and stirring rate on the dispersibility and the charge property of samples have been discussed. The results indicate the settle time of modified TiO can last 120 h with the response time of 35 s under the optimized modifying conditions, in which temperature is 85°C–90°C, pH is 8–9 and stirring rate is 800 r · min. The dispersibility and electrophoretic mobility have been significantly improved, which means that the modified TiO is suitable for electrophoretic ink particles.

关键词: inorganic particle     temperature     tetrachloroethylene     transform     optimized modifying    

Characterisation of a microwave induced plasma torch for glass surface modification

Adam BENNETT, Nan YU, Fengzhou FANG, Marco CASTELLI, Guoda CHEN, Alessio BALLERI, Takuya URAYAMA

《机械工程前沿(英文)》 2021年 第16卷 第1期   页码 122-132 doi: 10.1007/s11465-020-0603-5

摘要: Microwave induced plasma torches find wide applications in material and chemical analysis. Investigation of a coaxial electrode microwave induced plasma (CE–MIP) torch is conducted in this study, making it available for glass surface modification and polishing. A dedicated nozzle is designed to inject secondary gases into the main plasma jet. This study details the adaptation of a characterisation process for CE–MIP technology. Microwave spectrum analysis is used to create a polar plot of the microwave energy being emitted from the coaxial electrode, where the microwave energy couples with the gas to generate the plasma jet. Optical emission spectroscopy analysis is also employed to create spatial maps of the photonic intensity distribution within the plasma jet when different additional gases are injected into it. The CE–MIP torch is experimentally tested for surface energy modification on glass where it creates a super-hydrophilic surface.

关键词: microwave induced plasma     spectrum analysis     surface modification    

Tubes with coated and sintered porous surface for highly efficient heat exchangers

Hong Xu, Yulin Dai, Honghai Cao, Jinglei Liu, Li Zhang, Mingjie Xu, Jun Cao, Peng Xu, Jianshu Liu

《化学科学与工程前沿(英文)》 2018年 第12卷 第3期   页码 367-375 doi: 10.1007/s11705-018-1703-1

摘要:

Surface modification is a direct and effective way to enhance the efficiency of heat exchangers. Surface modification by forming a microporous coated layer can greatly enhance the boiling heat transfer and thus achieve a high performance. In this paper, we systematically investigate the boiling behavior on a plain surface with/without sintered microporous coatings of copper powder. The results demonstrated that the sintered surface has a better performance in nucleate boiling due to the increased nucleation sites. The superheat degree is lower and the bubble departure diameter is larger for the sintered surface than for the plain surface, so the heat can be carried away more efficiently on the sintered surface. In addition, the heat transfer capacity on the sintered surface depends on both the powder size and the coating thickness for a high flux tube. The optimum heat transfer capacity can be obtained when the thickness of the microporous coating layer is 3–5 times of the sintered powder diameter. As a result, the heat transfer coefficient tube can be up to 3 times higher for the tube with a sintered surface than that with a plain surface, showing a pronounced enhancement in heat transfer and a high potential in chemical engineering industry application.

关键词: microporous coating layer     surface modification     boiling enhancement     sintering    

Biodegradable, superhydrophobic walnut wood membrane for the separation of oil/water mixtures

《化学科学与工程前沿(英文)》 2022年 第16卷 第9期   页码 1377-1386 doi: 10.1007/s11705-022-2157-z

摘要: The preparation of environmentally friendly oil/water separation materials remains a great challenge. Freeze-drying of wood after lignin removal yields wood aerogels, which can be used as substrates to prepare fluorine-free environmentally friendly superhydrophobic materials, However, they are more suitable for absorption rather than filtration applications due to their poor strength. A study using cross-sections of pristine wood chips as substrates retains the original strength of wood, but the use of the cross-sectional of wood pieces limits their thickness, strength, and size. In this paper, a degradable fluorine-free superhydrophobic film (max. water contact angle of approximately 164.2°) with self-cleaning and abrasion resistance characteristics was prepared by a one-step method using pristine and activated walnut longitudinal section films as the substrate, with tetraethyl orthosilicate as a precursor and dodecyltriethoxysilane as a modifier. The tensile strength results show that superhydrophobic films with pristine or activated wood substrates maintained the strength of pristine wood and were 2.2 times stronger than the wood aerogel substrate. In addition, after cross-laminating the two samples, the films had the ability to separate oil and water by continuous filtration with high efficiency (98.5%) and flux (approximately 1.3 × 103 L∙m‒2∙h‒1). The method has potential for the large-scale fabrication of degradable superhydrophobic filtration separation membranes.

关键词: wood nanotechnology     superhydrophobic     biodegradable     surface modification     oil/water separation    

Surface-tailoring chlorine resistant materials and strategies for polyamide thin film composite reverse

《化学科学与工程前沿(英文)》 2022年 第16卷 第5期   页码 564-591 doi: 10.1007/s11705-021-2109-z

摘要: Polyamide thin film composite membranes have dominated current reverse osmosis market on account of their excellent separation performances compared to the integrally skinned counterparts. Despite their very promising separation performance, chlorine-induced degradation resulted from the susceptibility of polyamide toward chlorine attack has been regarded as the Achilles’s heel of polyamide thin film composite. The free chlorine species present during chlorine treatment can impair membrane performance through chlorination and depolymerization of the polyamide selective layer. From material point of view, a chemically stable membrane is crucial for the sustainable application of membrane separation process as it warrants a longer membrane lifespan and reduces the cost involved in membrane replacement. Various strategies, particularly those involved membrane material optimization and surface modifications, have been established to address this issue. This review discusses membrane degradation by free chlorine attack and its correlation with the surface chemistry of polyamide. The advancement in the development of chlorine resistant polyamide thin film composite membranes is reviewed based on the state-of-the-art surface modifications and tailoring approaches which include the in situ and post-fabrication membrane modifications using a broad range of functional materials. The challenges and future directions in this field are also highlighted.

关键词: reverse osmosis     polyamide     thin film composite membranes     chlorine resistance     surface modification    

Upgrading pyrolytic carbon-blacks (CBp) from end-of-life tires: Characteristics and modification methodologies

Jiaxue Yu, Junqing Xu, Zhenchen Li, Wenzhi He, Juwen Huang, Junshi Xu, Guangming Li

《环境科学与工程前沿(英文)》 2020年 第14卷 第2期 doi: 10.1007/s11783-019-1198-0

摘要: Modification methodologies of upgrading CBp from ELTs were reviewed. Surface microstructures and physiochemical properties of CBp were analyzed. Future perspectives of ELTs pyrolysis industries were suggested. Over 1 billion end-of-life tires (ELTs) are generating annually, and 4 billion ELTs are currently abandoned in landfills and stockpiles worldwide, according to the statistics, leading to the environmental and health risks. To circumvent these issues, pyrolysis, as an attractive thermochemical process, has been addressed to tackle the ELTs’ problem to reduce the risks as well as increase the material recycling. However, due to the lack of systematic characteristic analysis and modification methods, poor quality of CBp limits the improvement of ELTs pyrolysis in industry applications, which plays a crucial role in the economic feasibility of pyrolysis process. In this review, we have summarized the state-of-the-art characteristics and modification methodologies of the upgrading of CBp, to in-depth understand the surface microstructures and physiochemical properties of CBp for the foundation for modification afterwards. By virtue of the proper selection of modification methods and modifying agents, the new generation of multifunctional carbon materials with desired properties can be instead of the traditional materials of CB, promising broader and various application fields.

关键词: Pyrolysis carbon-blacks     CBp     Post-pyrolysis     Demineralization     Surface modification    

标题 作者 时间 类型 操作

Surface modification techniques of membranes to improve their antifouling characteristics: recent advancements

期刊论文

Tribological study on the surface modification of metal-on-polymer bioimplants

期刊论文

Improved blending strategy for membrane modification by virtue of surface segregation using surface-tailored

Shuai Liang, Peng Gao, Xiaoqi Gao, Kang Xiao, Xia Huang

期刊论文

Feasibility of bubble surface modification for natural organic matter removal from river water using

Yulong Shi, Jiaxuan Yang, Jun Ma, Congwei Luo

期刊论文

Surface modification by ligand growth strategy for dense copper bismuth film as photocathode to enhance

期刊论文

Surface modification of cellulose nanocrystals

WANG Neng, DING Enyong, CHENG Rongshi

期刊论文

激光表面改性技术发展研究

张群莉,王梁,梅雪松,姚建华

期刊论文

Modification of polycarbonateurethane surface with poly(ethylene glycol) monoacrylate and phosphorylcholine

Jing YANG,Juan LV,Bin GAO,Li ZHANG,Dazhi YANG,Changcan SHI,Jintang GUO,Wenzhong LI,Yakai FENG

期刊论文

Surface modification of biomaterials by photochemical immobilization and photograft polymerization to

Yakai FENG, Haiyang ZHAO, Li ZHANG, Jintang GUO,

期刊论文

Surface modification of titanium dioxide for electrophoretic particles

PENG Xuhui, LE Yuan, BIAN Shuguang, LI Woyuan, WU Wei, DAI Haitao, CHEN Jianfeng

期刊论文

Characterisation of a microwave induced plasma torch for glass surface modification

Adam BENNETT, Nan YU, Fengzhou FANG, Marco CASTELLI, Guoda CHEN, Alessio BALLERI, Takuya URAYAMA

期刊论文

Tubes with coated and sintered porous surface for highly efficient heat exchangers

Hong Xu, Yulin Dai, Honghai Cao, Jinglei Liu, Li Zhang, Mingjie Xu, Jun Cao, Peng Xu, Jianshu Liu

期刊论文

Biodegradable, superhydrophobic walnut wood membrane for the separation of oil/water mixtures

期刊论文

Surface-tailoring chlorine resistant materials and strategies for polyamide thin film composite reverse

期刊论文

Upgrading pyrolytic carbon-blacks (CBp) from end-of-life tires: Characteristics and modification methodologies

Jiaxue Yu, Junqing Xu, Zhenchen Li, Wenzhi He, Juwen Huang, Junshi Xu, Guangming Li

期刊论文