As system of a serial of technologies and engineering activities, remanufacturing aims at restoring and rebuilding waste machinery through advanced technologies and industrialized measures under the direction of the p...As system of a serial of technologies and engineering activities, remanufacturing aims at restoring and rebuilding waste machinery through advanced technologies and industrialized measures under the direction of the product total life cycle theory. With the development of surface engineering, nano-surface engineering has been one subject of intensive studies. In addition, nano-surface engineering has become an important means for property reforming and promoting of remanufacturing parts. Many low-dimension and nano-size or nano-structure functional coatings, which can improve materials properties evidently, are deposited by new methods. In this paper, some researches about the new achievement and remanufacturing application of the nano-stmctured coatings by different nano-surface engineering technologies in our laboratory were introduced. Especially, nano-structured DLC multilayer coatings by d.c. plasma CVD, nano-composed Al2O3/Ni, SiC/Ni and Diamond/Ni coatings by brush plating, and nano-composed Al2O3/TiO2 coating by plasma spraying were introduced in detail.展开更多
The mechanism of transport of chemicals in soil is an important research topic of environmental science and engineering, and some models and methods for a variety of solute transport problems have been done. Howeve...The mechanism of transport of chemicals in soil is an important research topic of environmental science and engineering, and some models and methods for a variety of solute transport problems have been done. However. most of previous works are usually for a soil column of infinite dimension. Starting from the one-dimension transient solute transport equation and its boundary and initial condition for a solute transport problem of soil column of finite length, this work has successfully applied a variable transformation to simplify the partial differential equation of solute transport problem. And an analytical serial solution for the simplified equation is then established by the so-called separated variable method and the superposition method. Compared with numerical methods such as finite different method and finite element method, this analytical solution is more accurate and of higher computation efficiency. In addition, the solution procedure presented could be extended for applications such as quality analysis, design of physical experimentation, or parameter estimation and measurement of solute transport problems.展开更多
A short presentation of chemical engineering evolution,as guided by its paradigms,is exposed.The first paradigm–unit operations–has emerged as a necessity of systematization due to the explosion of chemical industri...A short presentation of chemical engineering evolution,as guided by its paradigms,is exposed.The first paradigm–unit operations–has emerged as a necessity of systematization due to the explosion of chemical industrial applications at the end of 19th century.The birth in the late 1950s of the second paradigm–transport phenomena–was the consequence of the need for a deep,scienti fic knowledge of the phenomena that explain what happens inside of unit operations.In the second part of 20th century,the importance of chemical product properties and qualities has become essentially in the market fights.Accordingly,it was required with additional and even new fundamental approaches,and product engineering was recognized as the third paradigm.Nowadays chemical industry,as a huge materials and energy consumer,and with a strong ecological impact,couldn't remain outside of sustainability requirements.The basics of the fourth paradigm–sustainable chemical engineering–are now formulated.展开更多
Since aptamer and its in vitro selection process called SELEX were independently described by Ellington and Gold in 1990, extensive research has been undertaken and numerous isolated aptamers for various targets have ...Since aptamer and its in vitro selection process called SELEX were independently described by Ellington and Gold in 1990, extensive research has been undertaken and numerous isolated aptamers for various targets have been applied. Aptamers can bind to a wide range of targets that include small organic molecules, inorganic compounds, haptens and even whole cells with high binding affinity and specificity. Aptamers for a wide range of targets have been selected currently. In addition, aptamers are thermo stable and can also be regenerated easily within a few minutes denaturation, which makes them easy to store or handle. These advantages make aptamers extremely suitable for applications based on molecular recognition as analytical, diagnostic and therapeutic tools. In this review, the recent applications of aptamers for chemistry analysis, medicine and food security, along with the future trend will be discussed.展开更多
Continuous usage of bioreactor causes early degradation of most bioreactor liner materials due to the effects of various chemicals, consequently resulting in contamination in the bioprocess. Performance of PP-ternary ...Continuous usage of bioreactor causes early degradation of most bioreactor liner materials due to the effects of various chemicals, consequently resulting in contamination in the bioprocess. Performance of PP-ternary nanocomposite (PPTN) for its potential application in the fabrication of bioreactor liner material was investigated in this study. The chemical resistance of the composite samples obtained was tested by exposing them to chemicals such as acid, alkaline, water and bacterial solutions, according to ASTM 543-06, and their effects on the composite samples were carefully observed. Specifically, the investigation focused on the changes in the physico-mechanical properties of PPTN following long term of exposure to these chemicals. The results show slight increase in the weight and dimensions of samples in the first few days, followed by constant reading for the period of 4 weeks. The performance in terms of physical properties was in the range of PPTN with 0.61% MWCNT > PPTN 0.45% > PPTN 0.17%. The maximum percentage change in tensile properties, observed in this study, was approximately 10% against PPTN (0.17%), which indicates stable mechanical properties of the composite and invariably suggests that the nanocomposites could serve as a better alternative for bioreactor liner fabrication.展开更多
基金National"973"Projects (G1999065009) andNational Natural Science Foundation of China (50075086)
文摘As system of a serial of technologies and engineering activities, remanufacturing aims at restoring and rebuilding waste machinery through advanced technologies and industrialized measures under the direction of the product total life cycle theory. With the development of surface engineering, nano-surface engineering has been one subject of intensive studies. In addition, nano-surface engineering has become an important means for property reforming and promoting of remanufacturing parts. Many low-dimension and nano-size or nano-structure functional coatings, which can improve materials properties evidently, are deposited by new methods. In this paper, some researches about the new achievement and remanufacturing application of the nano-stmctured coatings by different nano-surface engineering technologies in our laboratory were introduced. Especially, nano-structured DLC multilayer coatings by d.c. plasma CVD, nano-composed Al2O3/Ni, SiC/Ni and Diamond/Ni coatings by brush plating, and nano-composed Al2O3/TiO2 coating by plasma spraying were introduced in detail.
基金Acknowledgements: The work was supported by the National Natural Science Foundation of China (No. 90502006/D0123), Hunan provincial Natural Science Foundation of China (No. 06JJ3020) and Scientific Research Fund of Hunan Provincial Education Department (No. 06C500).
文摘The mechanism of transport of chemicals in soil is an important research topic of environmental science and engineering, and some models and methods for a variety of solute transport problems have been done. However. most of previous works are usually for a soil column of infinite dimension. Starting from the one-dimension transient solute transport equation and its boundary and initial condition for a solute transport problem of soil column of finite length, this work has successfully applied a variable transformation to simplify the partial differential equation of solute transport problem. And an analytical serial solution for the simplified equation is then established by the so-called separated variable method and the superposition method. Compared with numerical methods such as finite different method and finite element method, this analytical solution is more accurate and of higher computation efficiency. In addition, the solution procedure presented could be extended for applications such as quality analysis, design of physical experimentation, or parameter estimation and measurement of solute transport problems.
文摘A short presentation of chemical engineering evolution,as guided by its paradigms,is exposed.The first paradigm–unit operations–has emerged as a necessity of systematization due to the explosion of chemical industrial applications at the end of 19th century.The birth in the late 1950s of the second paradigm–transport phenomena–was the consequence of the need for a deep,scienti fic knowledge of the phenomena that explain what happens inside of unit operations.In the second part of 20th century,the importance of chemical product properties and qualities has become essentially in the market fights.Accordingly,it was required with additional and even new fundamental approaches,and product engineering was recognized as the third paradigm.Nowadays chemical industry,as a huge materials and energy consumer,and with a strong ecological impact,couldn't remain outside of sustainability requirements.The basics of the fourth paradigm–sustainable chemical engineering–are now formulated.
基金supported by the 863 Project(2012AA022703,2015AA020502)the National Natural Science Foundation of China(61271056)
文摘Since aptamer and its in vitro selection process called SELEX were independently described by Ellington and Gold in 1990, extensive research has been undertaken and numerous isolated aptamers for various targets have been applied. Aptamers can bind to a wide range of targets that include small organic molecules, inorganic compounds, haptens and even whole cells with high binding affinity and specificity. Aptamers for a wide range of targets have been selected currently. In addition, aptamers are thermo stable and can also be regenerated easily within a few minutes denaturation, which makes them easy to store or handle. These advantages make aptamers extremely suitable for applications based on molecular recognition as analytical, diagnostic and therapeutic tools. In this review, the recent applications of aptamers for chemistry analysis, medicine and food security, along with the future trend will be discussed.
基金the Malaysia Ministry of Higher Education (MOHE) for funding this project under FRGS 0206-56
文摘Continuous usage of bioreactor causes early degradation of most bioreactor liner materials due to the effects of various chemicals, consequently resulting in contamination in the bioprocess. Performance of PP-ternary nanocomposite (PPTN) for its potential application in the fabrication of bioreactor liner material was investigated in this study. The chemical resistance of the composite samples obtained was tested by exposing them to chemicals such as acid, alkaline, water and bacterial solutions, according to ASTM 543-06, and their effects on the composite samples were carefully observed. Specifically, the investigation focused on the changes in the physico-mechanical properties of PPTN following long term of exposure to these chemicals. The results show slight increase in the weight and dimensions of samples in the first few days, followed by constant reading for the period of 4 weeks. The performance in terms of physical properties was in the range of PPTN with 0.61% MWCNT > PPTN 0.45% > PPTN 0.17%. The maximum percentage change in tensile properties, observed in this study, was approximately 10% against PPTN (0.17%), which indicates stable mechanical properties of the composite and invariably suggests that the nanocomposites could serve as a better alternative for bioreactor liner fabrication.