A novel adsorbent was prepared by modifying orange peel with sodium hydroxide and calcium chloride. The morphological and characteristics of the adsorbent were evaluated by infrared spectroscopy (IR), scanning elect...A novel adsorbent was prepared by modifying orange peel with sodium hydroxide and calcium chloride. The morphological and characteristics of the adsorbent were evaluated by infrared spectroscopy (IR), scanning electron microscopy (SEM) and N2-adsorption techniques. The adsorption behavior of Cu^2+, Pb^2+ and Zn^2+ on modified orange peel (SCOP) was studied by varying parameters like pH, initial concentration of metal ions. Equilibrium was well described by Langmuir equation with the maximum adsorption capacities for Cu^2+, Pb^2+ and Zn^2+ of 70.73, 209.8 and 56.18 mg/g, respectively. Based on the results obtained in batch experiments, breakthrough profiles were examined using a column packed with SCOP for the separation of small concentration of Pb^2+ from an excess of Zn^2+ followed by elution tests. Ion exchange with Ca^2+ neutralizing the carboxyl groups of the pectin was found to be the predominant mechanism.展开更多
Modified potential ecological risk index (MRI) was proposed based on the potential ecological risk index (RI) and risk assessment code (RAC) by modifying an index. The modified index was relevant to the chemical...Modified potential ecological risk index (MRI) was proposed based on the potential ecological risk index (RI) and risk assessment code (RAC) by modifying an index. The modified index was relevant to the chemical speciation of heavy metals. Xiawan Port, a typical region contaminated by industrial production, was selected as a case study area. The total concentrations and chemical speciation of heavy metals in sediments of Xiawan Port were analyzed. The experimental data indicate that Xiawan Port is seriously polluted by heavy metals, especially by Cd. The risks of heavy metals are evaluated by RI, RAC and MRI, respectively. The resluts of MRI show that the risks of heavy metals are in the decreasing order of Cd〉Pb〉Cu〉Zn. Comparison of results by different methods reveals that MRI integrates the characters of RI and RAC. MRI is recognized to be useful for risk managemnt of heavy metals in sediments.展开更多
A Ni layer with a thickness of about 100 nm was sputtered on Cu substrates,followed by an ultrasonic seeding with nanodiamond suspension.High-quality diamond film with its crystalline grains close to thermal equilibri...A Ni layer with a thickness of about 100 nm was sputtered on Cu substrates,followed by an ultrasonic seeding with nanodiamond suspension.High-quality diamond film with its crystalline grains close to thermal equilibrium shape was deposited on Cu substrates by hot-filament chemical vapor deposition(HF-CVD),and the sp2 carbon content was less than 5.56%.The nucleation and growth of diamond film were investigated by micro-Raman spectroscopy,scanning electron microscopy,and X-ray diffraction.The results show that the nucleation density of diamond on the Ni-modified Cu substrates is 10 times higher than that on blank Cu substrates.The enhancement mechanism of the nucleation kinetics by Ni modification layer results from two effects:namely,the nanometer rough Ni-modified surface shows an improved absorption of nanodiamond particles that act as starting points for the diamond nucleation during HF-CVD process;the strong catalytic effect of the Ni-modified surface causes the formation of graphite layer that acts as an intermediate to facilitate diamond nucleation quickly.展开更多
This paper analyzes the negative influence of traditional English instruction as well as obsession with bilingual teaching, and sets forth a three-step development strategy in line with the cognitive characteristics o...This paper analyzes the negative influence of traditional English instruction as well as obsession with bilingual teaching, and sets forth a three-step development strategy in line with the cognitive characteristics of learners.展开更多
This research adopted four methods to toughen epoxy adhesives. They were liquid hydroxyl group terminated polybutadiene (HTPB) rubber modification, silicon rubber modification, polyacrylate multiplicity elastomer par...This research adopted four methods to toughen epoxy adhesives. They were liquid hydroxyl group terminated polybutadiene (HTPB) rubber modification, silicon rubber modification, polyacrylate multiplicity elastomer particulates emulsion modification and chemical grafting modification. After modification, the shearing strength and the rupture elongation were tested. The interface and the chemical reaction between the modifiers and the epoxy were analyzed by scanning electron microscope (SEM) and infrared optical spectrum. The results show that the elastomer particulates modification and the chemical grafting modification can reach the better toughening effects.展开更多
This paper presents some reflections on non-English major postgraduate English teaching reform. The author points out some understandings on the English proficiency of non-English major postgraduate students and curri...This paper presents some reflections on non-English major postgraduate English teaching reform. The author points out some understandings on the English proficiency of non-English major postgraduate students and curriculum changes in the reform. The author thinks that postgraduate English teaching reform is a systematic project, with a goal to meet the practical needs of postgraduate students and improve their ability to use English in their study and work. Hence, every effort of the reform should be made to satisfy the practical needs of the students and to make their English study contribute to their achievements in their own subject area.展开更多
Viscose activated carbon fibers (ACFs) were characterized using specific surface area, scanning electron modified with chemical vapor deposition (CVD). The samples were microscopy (SEM), pore size distribution a...Viscose activated carbon fibers (ACFs) were characterized using specific surface area, scanning electron modified with chemical vapor deposition (CVD). The samples were microscopy (SEM), pore size distribution and Fourier transform infrared spectroscopy (FTIR). Batch adsorption experiments were carried out to investigate the adsorption behavior of modified ACFs for methyl orange(MO) from its aqueous solutions. The results show that the adsorption isotherms of MO onto modified ACFs well follows the Langmuir isotherm equation. The adsorption kinetics of MO can be well described by the pseudo second-order kinetic model. The adsorption process involves the intra-particle diffusion, but is not the only rate-controlling step. Thermodynamic parameters including AG, AH and AS were calculated, suggesting that the adsorption of MO onto modified ACFs is a spontaneous, exothermic and physisorption process. FTIR result indicates that the major adsorption mechanism of modified ACFs for MO is hydrogen bond.展开更多
This paper is a report of an experimental undergraduate composite program of Tourism Business Management and English. It introduces the characteristics of the program structure, faculty, learning materials, teaching a...This paper is a report of an experimental undergraduate composite program of Tourism Business Management and English. It introduces the characteristics of the program structure, faculty, learning materials, teaching and learning methods, and assessment approaches. The achievements of the program as well as the major problems it has experienc.ed are also discussed.展开更多
Non-English majors' evaluation on teachers is a vital way to get feedback of English language classroom teaching and learning. This paper reports on a study which used a discourse-analytic approach to look into the e...Non-English majors' evaluation on teachers is a vital way to get feedback of English language classroom teaching and learning. This paper reports on a study which used a discourse-analytic approach to look into the existing problems in English classroom teaching at undergraduates' level. The ways of searching solutions for the problems are also discussed.展开更多
In pace with the constant increase of exchange with other countries, the traditional teaching approach cannot meet the demand of modem education. But the communicative approach conforms to historical trends, focusing ...In pace with the constant increase of exchange with other countries, the traditional teaching approach cannot meet the demand of modem education. But the communicative approach conforms to historical trends, focusing on students and developing their overall language ability to handle changes and solve problems. Proceeding from the tortuous course of teaching reform on English, analyzing theories of foreign language approaches and characteristics of communicative approach and researching into its strategies, the author aims to study how to spur teaching reform on college English towards great success.展开更多
The improved Intermig impeller has been used in the seed precipitation tank in China, which could enhance the mixing and suspension of Al(OH)3 particles and the power consumption declined largely. The flow field, soli...The improved Intermig impeller has been used in the seed precipitation tank in China, which could enhance the mixing and suspension of Al(OH)3 particles and the power consumption declined largely. The flow field, solids hold-up, cloud height, just off-bottom speed and power consumptions were investigated in solid-liquid mixing system with this new type of impeller by CFD and water experiment methods. Compared with the standard Intermig impeller, the improved one coupled with specially sloped baffles could promote the fluid circulation, create better solids suspension and consume less power. Besides lower impeller off-bottom clearance is good for solid suspension and distribution. The just-off-bottom speed was also determined by a power number criterion. Meanwhile, the predicted results were in good agreement with the experimental data.展开更多
This paper intends to discuss the types of team teaching, its advantages and disadvantages in the English teaching practice in China and provide some specific tips for both Chinese and foreign English teachers in team...This paper intends to discuss the types of team teaching, its advantages and disadvantages in the English teaching practice in China and provide some specific tips for both Chinese and foreign English teachers in team teaching.展开更多
As a green and sustainable technology,heterogeneous photocatalysis using semiconductors has received much attention during the past decades because of its potential to address energy and environmental problems. Among ...As a green and sustainable technology,heterogeneous photocatalysis using semiconductors has received much attention during the past decades because of its potential to address energy and environmental problems. Among various semiconductors,TiO2 has been regarded as the best and most widely investigated photocatalyst in the past 10 years. Based on the fundamentals of photocatalysis and surface chemistry of TiO2 nanomaterials,we herein summarize and discuss the achievements in the different surface modification strategies employed to date such as surface doping and sensitization,construction of surface heterojunctions,loading of nano-sized co-catalysts,increase in the accessible surface areas,and usage of surface F effects and exposure of highly reactive facets. Especially,the interesting synergistic effects of these different surface modification strategies deserve more attention in the near future. Studying these important advances in photocatalysis fundamentals,and surface chemistry and modification may offer new opportunities for designing highly efficient TiO2-based and non-TiO2-based photocatalysts for solar fuel production,environmental remediation,organic photosynthesis,and other related fields such as solar cell device fabrication,thermal catalysis,and separation and purification.展开更多
A novel thermosetting resin system for superabrasives based on novolak and bismaleimide (BMI) was developed. The novolak resin was allylated and then copolymerized with BMI. The structure of allyl novolak and reacti...A novel thermosetting resin system for superabrasives based on novolak and bismaleimide (BMI) was developed. The novolak resin was allylated and then copolymerized with BMI. The structure of allyl novolak and reaction mechanism were analyzed by FFIR. Thermal and mechanical properties were characterized by using com- prehensive thermal analyzer (DSC-TG) and strength tester, respectively. The results showed that high molecular weight of novolak was advantageous for heat-resistance, but was unfavorable for the bending strength. High allyl content improved the heat-resistance but lowered the bending strength. When the molecular weight of novolak was 450 and allyl content was 50%, the best resin system with good heat-resistance and bending strength was obtained. It was suitable for the manufacturing of superabrasive tools.展开更多
Wetting condition of micro/nanostructured surface has received tremendous attention due to the potential applications in commercial,industrial,and military areas.Surfaces with extreme wetting properties,e.g.,superhydr...Wetting condition of micro/nanostructured surface has received tremendous attention due to the potential applications in commercial,industrial,and military areas.Surfaces with extreme wetting properties,e.g.,superhydrophobic or superhydrophilic,are extensively employed due to their superior anti-icing,drag reduction,enhanced boiling heat transfer,self-cleaning,and anti-bacterial properties depending on solid-liquid interfacial interactions.Laser-based techniques have gained popularity in recent years to create micro/nano-structured surface owing to their high flexibility,system precision,and ease for automation.These techniques create laser induced periodic surface structures(LIPSS)or hierarchical structures on substrate material.However,micro/nanostructures alone cannot attain the desired wettability.Subsequent modification of surface chemistry is essentially needed to achieve target extreme wettability.This review paper aims to provide a comprehensive review for both laser texturing techniques and the following chemistry modification methods.Recent research progress and fundamental mechanisms of surface structure generation via different types of lasers and various chemistry modification methods are discussed.The complex combination between the laser texturing and surface chemistry modification methods to decide the final wetting condition is presented.More importantly,surface functionalities of these surfaces with extreme wetting properties are discussed.Lastly,prospects for future research are proposed and discussed.展开更多
基金Project (50774100) supported by the National Natural Science Foundation of China
文摘A novel adsorbent was prepared by modifying orange peel with sodium hydroxide and calcium chloride. The morphological and characteristics of the adsorbent were evaluated by infrared spectroscopy (IR), scanning electron microscopy (SEM) and N2-adsorption techniques. The adsorption behavior of Cu^2+, Pb^2+ and Zn^2+ on modified orange peel (SCOP) was studied by varying parameters like pH, initial concentration of metal ions. Equilibrium was well described by Langmuir equation with the maximum adsorption capacities for Cu^2+, Pb^2+ and Zn^2+ of 70.73, 209.8 and 56.18 mg/g, respectively. Based on the results obtained in batch experiments, breakthrough profiles were examined using a column packed with SCOP for the separation of small concentration of Pb^2+ from an excess of Zn^2+ followed by elution tests. Ion exchange with Ca^2+ neutralizing the carboxyl groups of the pectin was found to be the predominant mechanism.
基金Projects (51039001, 50978087, 51009063, 50808071) supported by the National Natural Science Foundation of ChinaProject (SX2010-026) supported by State Council Three Gorges Project Construction Committee Executive Office,China+2 种基金Project (2009ZX07212-001) supported by Ministry of Environmental Protection of ChinaProject (BYHGLC-2010-02) supported by Guangzhou Water Authority,ChinaProject (CX2010B157) supported by Hunan Provincial Innovation Foundation for Postgraduate,China
文摘Modified potential ecological risk index (MRI) was proposed based on the potential ecological risk index (RI) and risk assessment code (RAC) by modifying an index. The modified index was relevant to the chemical speciation of heavy metals. Xiawan Port, a typical region contaminated by industrial production, was selected as a case study area. The total concentrations and chemical speciation of heavy metals in sediments of Xiawan Port were analyzed. The experimental data indicate that Xiawan Port is seriously polluted by heavy metals, especially by Cd. The risks of heavy metals are evaluated by RI, RAC and MRI, respectively. The resluts of MRI show that the risks of heavy metals are in the decreasing order of Cd〉Pb〉Cu〉Zn. Comparison of results by different methods reveals that MRI integrates the characters of RI and RAC. MRI is recognized to be useful for risk managemnt of heavy metals in sediments.
基金Project(20110933K) supported by the State Key Laboratory of Powder Metallurgy,ChinaProject(2012QNZT002) supported by the Freedom Explore Program of Central South University,ChinaProject(CSUZC2012024) supported by the Open-End Fund for the Valuable and Precision Instruments of Central South University,China
文摘A Ni layer with a thickness of about 100 nm was sputtered on Cu substrates,followed by an ultrasonic seeding with nanodiamond suspension.High-quality diamond film with its crystalline grains close to thermal equilibrium shape was deposited on Cu substrates by hot-filament chemical vapor deposition(HF-CVD),and the sp2 carbon content was less than 5.56%.The nucleation and growth of diamond film were investigated by micro-Raman spectroscopy,scanning electron microscopy,and X-ray diffraction.The results show that the nucleation density of diamond on the Ni-modified Cu substrates is 10 times higher than that on blank Cu substrates.The enhancement mechanism of the nucleation kinetics by Ni modification layer results from two effects:namely,the nanometer rough Ni-modified surface shows an improved absorption of nanodiamond particles that act as starting points for the diamond nucleation during HF-CVD process;the strong catalytic effect of the Ni-modified surface causes the formation of graphite layer that acts as an intermediate to facilitate diamond nucleation quickly.
文摘This paper analyzes the negative influence of traditional English instruction as well as obsession with bilingual teaching, and sets forth a three-step development strategy in line with the cognitive characteristics of learners.
文摘This research adopted four methods to toughen epoxy adhesives. They were liquid hydroxyl group terminated polybutadiene (HTPB) rubber modification, silicon rubber modification, polyacrylate multiplicity elastomer particulates emulsion modification and chemical grafting modification. After modification, the shearing strength and the rupture elongation were tested. The interface and the chemical reaction between the modifiers and the epoxy were analyzed by scanning electron microscope (SEM) and infrared optical spectrum. The results show that the elastomer particulates modification and the chemical grafting modification can reach the better toughening effects.
文摘This paper presents some reflections on non-English major postgraduate English teaching reform. The author points out some understandings on the English proficiency of non-English major postgraduate students and curriculum changes in the reform. The author thinks that postgraduate English teaching reform is a systematic project, with a goal to meet the practical needs of postgraduate students and improve their ability to use English in their study and work. Hence, every effort of the reform should be made to satisfy the practical needs of the students and to make their English study contribute to their achievements in their own subject area.
基金Project (50802115) supported by the National Natural Science Foundation of ChinaProject (2010FJ4075) supported by Science and Technology Planning Project of Hunan Province, China+1 种基金Project (CDJJ-10010205) supported by the Science Foundation of Changsha University, ChinaProject supported by the Construct Program of the Key Discipline in Hunan Province, China
文摘Viscose activated carbon fibers (ACFs) were characterized using specific surface area, scanning electron modified with chemical vapor deposition (CVD). The samples were microscopy (SEM), pore size distribution and Fourier transform infrared spectroscopy (FTIR). Batch adsorption experiments were carried out to investigate the adsorption behavior of modified ACFs for methyl orange(MO) from its aqueous solutions. The results show that the adsorption isotherms of MO onto modified ACFs well follows the Langmuir isotherm equation. The adsorption kinetics of MO can be well described by the pseudo second-order kinetic model. The adsorption process involves the intra-particle diffusion, but is not the only rate-controlling step. Thermodynamic parameters including AG, AH and AS were calculated, suggesting that the adsorption of MO onto modified ACFs is a spontaneous, exothermic and physisorption process. FTIR result indicates that the major adsorption mechanism of modified ACFs for MO is hydrogen bond.
文摘This paper is a report of an experimental undergraduate composite program of Tourism Business Management and English. It introduces the characteristics of the program structure, faculty, learning materials, teaching and learning methods, and assessment approaches. The achievements of the program as well as the major problems it has experienc.ed are also discussed.
文摘Non-English majors' evaluation on teachers is a vital way to get feedback of English language classroom teaching and learning. This paper reports on a study which used a discourse-analytic approach to look into the existing problems in English classroom teaching at undergraduates' level. The ways of searching solutions for the problems are also discussed.
文摘In pace with the constant increase of exchange with other countries, the traditional teaching approach cannot meet the demand of modem education. But the communicative approach conforms to historical trends, focusing on students and developing their overall language ability to handle changes and solve problems. Proceeding from the tortuous course of teaching reform on English, analyzing theories of foreign language approaches and characteristics of communicative approach and researching into its strategies, the author aims to study how to spur teaching reform on college English towards great success.
基金Projects(50974035,51074047)supported by the National Natural Science Foundation of ChinaProject(2010AA03A405)supported by the High-tech Research and Development Program of China
文摘The improved Intermig impeller has been used in the seed precipitation tank in China, which could enhance the mixing and suspension of Al(OH)3 particles and the power consumption declined largely. The flow field, solids hold-up, cloud height, just off-bottom speed and power consumptions were investigated in solid-liquid mixing system with this new type of impeller by CFD and water experiment methods. Compared with the standard Intermig impeller, the improved one coupled with specially sloped baffles could promote the fluid circulation, create better solids suspension and consume less power. Besides lower impeller off-bottom clearance is good for solid suspension and distribution. The just-off-bottom speed was also determined by a power number criterion. Meanwhile, the predicted results were in good agreement with the experimental data.
文摘This paper intends to discuss the types of team teaching, its advantages and disadvantages in the English teaching practice in China and provide some specific tips for both Chinese and foreign English teachers in team teaching.
基金supported by the Industry and Research Collaborative Innovation Major Projects Of Guangzhou(201508020098)the National Natural Science Foundation of China(20906034+2 种基金21173088and 21207041)the State Key Laboratory of Advanced Technology for Material Synthesis and Processing,Wuhan University of Technology(2015-KF-7)~~
文摘As a green and sustainable technology,heterogeneous photocatalysis using semiconductors has received much attention during the past decades because of its potential to address energy and environmental problems. Among various semiconductors,TiO2 has been regarded as the best and most widely investigated photocatalyst in the past 10 years. Based on the fundamentals of photocatalysis and surface chemistry of TiO2 nanomaterials,we herein summarize and discuss the achievements in the different surface modification strategies employed to date such as surface doping and sensitization,construction of surface heterojunctions,loading of nano-sized co-catalysts,increase in the accessible surface areas,and usage of surface F effects and exposure of highly reactive facets. Especially,the interesting synergistic effects of these different surface modification strategies deserve more attention in the near future. Studying these important advances in photocatalysis fundamentals,and surface chemistry and modification may offer new opportunities for designing highly efficient TiO2-based and non-TiO2-based photocatalysts for solar fuel production,environmental remediation,organic photosynthesis,and other related fields such as solar cell device fabrication,thermal catalysis,and separation and purification.
文摘A novel thermosetting resin system for superabrasives based on novolak and bismaleimide (BMI) was developed. The novolak resin was allylated and then copolymerized with BMI. The structure of allyl novolak and reaction mechanism were analyzed by FFIR. Thermal and mechanical properties were characterized by using com- prehensive thermal analyzer (DSC-TG) and strength tester, respectively. The results showed that high molecular weight of novolak was advantageous for heat-resistance, but was unfavorable for the bending strength. High allyl content improved the heat-resistance but lowered the bending strength. When the molecular weight of novolak was 450 and allyl content was 50%, the best resin system with good heat-resistance and bending strength was obtained. It was suitable for the manufacturing of superabrasive tools.
基金Project(52105175)supported by the National Natural Science Foundation of ChinaProject(BK20210235)supported by the Natural Science Foundation of Jiangsu Province,ChinaProject(JSSCBS20210121)supported by the Jiangsu Provincial Innovative and Entrepreneurial Doctor Program,China。
文摘Wetting condition of micro/nanostructured surface has received tremendous attention due to the potential applications in commercial,industrial,and military areas.Surfaces with extreme wetting properties,e.g.,superhydrophobic or superhydrophilic,are extensively employed due to their superior anti-icing,drag reduction,enhanced boiling heat transfer,self-cleaning,and anti-bacterial properties depending on solid-liquid interfacial interactions.Laser-based techniques have gained popularity in recent years to create micro/nano-structured surface owing to their high flexibility,system precision,and ease for automation.These techniques create laser induced periodic surface structures(LIPSS)or hierarchical structures on substrate material.However,micro/nanostructures alone cannot attain the desired wettability.Subsequent modification of surface chemistry is essentially needed to achieve target extreme wettability.This review paper aims to provide a comprehensive review for both laser texturing techniques and the following chemistry modification methods.Recent research progress and fundamental mechanisms of surface structure generation via different types of lasers and various chemistry modification methods are discussed.The complex combination between the laser texturing and surface chemistry modification methods to decide the final wetting condition is presented.More importantly,surface functionalities of these surfaces with extreme wetting properties are discussed.Lastly,prospects for future research are proposed and discussed.