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Ce(SO_4)_2-mediated Oxidative Coupling of Primary Aromatic Amines in Water

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Chemical Research in Chinese Universities 2009年第5期25卷 638-643页

作者： LU Wen-chao XI chan-juan Key Laboratory of Bioorganic Phosphorus Chemistry ＆ Chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beo＇ing 100084 P. R. China

The oxidative coupling of primary aromatic amines was investigated. Ce（SO4）2 can mediate the oxidative coupling of primary aromatic amines in water to dimers, trimers and/or tetramers, which depended on the substituents of primary aromatic amines. When 2,6-dimethylaniline or 2,6-diethylaniline was used as substrate, dimer, and tetramer were formed as major products. When 2,6-diisopropylaniline or 2,6-dihaloanilines was used as substrate, dimer, and trimer were formed. The mechanistic aspect was also investigated.

关键词： Primary aromatic amine Oxidative coupling Cerium sulfate

Optimization of thermophilic anaerobic-aerobic treatment system for Palm Oil Mill Effluent （POME）

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Frontiers of Environmental Science & Engineering 2015年第2期9卷 334-351页

作者： Yijing chan Meifong CHONG Chunglim LAW Department of Chemical and Environmental Engineering The University of Nottingham Malaysia Campus Selangor 43500 Malaysia

Optimization of an integrated anaerobic-aero- bic bioreactor （IAAB） treatment system for the reduction of organic matter （Chemical Oxygen Demand （COD）, Biochemical Oxygen Demand （BOD） and Total Sus- pended Solids （TSS） concentrations） in Palm Oil Mill Effluent （POME） to legal standards with high methane yield was performed for the first time under thermophilic condition （50~C-55~C） by using response surface meth- odology （RSM）. The experiments were conducted based on a central composite rotatable design （CCRD） with three independent operating variables, organic loading rates in anaerobic compartment （OLRan） and mixed liquor volatile suspended solids （MLVSS） concentration in anaerobic （MLVSSa,） and aerobic compartments （MLVSSa）. The optimum conditions for the POME treatment were determined as OLRan of 15.6 g COD＇L-I＂d-1, MLVSSan of 43100mg.L l, and MLVSSa of 18600mg.L-1, where high aerobic COD, BOD and TSS removal efficiencies of 96.3%, 97.9%, and 98.5% were achieved with treated BOD of 56mg.L1 and TSS of *** meeting the discharge standard. This optimization study successfully achieved a reduction of 42% in the BOD concentrations of the final treated effluent at a 48% higher OLRan as compared to the previous works. Besides, thermophilic IAAB system scores better feasibility and higher effectiveness as compared to the optimized mesophilic system. This is due to its higher ability to handle high OLR with higher overall treatment efficiencies （more than 99.6%）, methane yield （0.31 L CH4＂ gl CODremoved） and purity of methane （67.5%）. Hence, these advantages ascertain the applicability ofthermophilic IAAB in the POME treatment or even in other high-strength wastewaters treatment.

关键词： palm oil mill effluent (POME) anaerobic aerobic thermophilic biogas optimization

Improved Dual-image Quality with Reversible Data Hiding Using Translocation and Switching Strategy

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Computer Systems Science & Engineering 2023年第2期44卷 1551-1566页

作者： Chin-Feng Lee Kuo-Chung chan Department of Information Management Chaoyang University of TechnologyTaichung41349Taiwan

Dual-image reversible data hiding(RDH)is a technique for hiding important *** technology can be used to safely deliver secret mes-sages to the recipient through dual images in an open network without being easily *** recipient of the image must receive the two stego-images before the secret message can be completely *** is one of the main advantages of data hiding technology;to increase the imperceptibility,the quality requirements of the stego-images are relatively important.A dual ste-ganographic image RDH method,called a DS-CF scheme that can achieve a bet-ter steganographic image quality using the center folding(CF)*** this paper,we developed a translocation and switching strategy(TaS)to shorten the distances between the stego-pixel coordinates and the cover pixel coordinates after information being *** with the DS-CF scheme,our proposed DS-TaS scheme can effectively improve the quality of the steganographic images at the same level of embedding *** experimental results show that the PSNR of our DS-TaS scheme at k=1 was 55.66 dB,which is an increase of 1.5 dB,and is 51.43 dB for k=2,46.66 dB for k=3,and 40.91 dB for k=*** addition,the PSNR values of the stego images was increased by 1.5,0.29,0.29,and 0.19 dB,*** shows that our proposed dual-image RDH method can optimize the visual quality of the stego-images and is better than many other dual-image RDH techniques.

关键词： Information hiding reversible data hiding(RDH) dual-image RDH center folding(CF)strategy

Phenomenology of rhythm in design

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Frontiers of Architectural Research 2012年第3期1卷 253-258页

作者： Chiu-Shui chan Department of Architecture 482 College of Design Iowa State University Ames Iowa 50011 USA School of Urban Design Wuhan University 430072 China

Rhythm in design, as explored in this research, is proposed to be the result of cognitive performance generated stylistically by creators and recognized consciously by beholders. This study describes the phenomenon of rhythm; how it is created; the factors that comprise rhythm; the types of rhythms created by human cognition of repetition, and why repetition is recognized as a part of human cognition. Images of seven buildings designed by Alvar Aalto are used to demonstrate the creation and expression of rhythm in building compositions. Evidence gathered in this research explains that rhythm in design is a result of the design method consciously applied by human cognition of repetition. Rules of generating the phenomena of rhythm are also summarized. Designers could apply these rules to generate harmonious patterns through the effective usage of repetition. In sum, rhythm is ingrained in the human conscience and therefore should be a key component of design applied universally.

关键词： Rhythm Repetition Phenomenotogy Design cognition Design thinking

A Review: Progress of Prevention and Control on Viral Hepatitis in China

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Biomedical and Environmental Sciences 1999年第3期12卷 227-232页

作者： GUOXIU－chan WUYI－QUN ChineseAcademyofPreventiveMedicine 27NanweiRoadBeijing100050 ChineseAcademyofPreventiveMedicine 27Na

There are six types of viral hepatitis, namely, A, B, C, D, E and G. Two types are mainly classified according to the routes of transmission. Hepatitis types A and E are transmitted by gastrointestinal tract (stool-mouth transmission). The others (B, C, D and G)are transmitted by parenteral route, the most common of which is blood transmission.

关键词： Public Health China Health Care Costs Hepatitis Viral Human Humans Risk Factors

Building metallurgical bonding interfaces in an immiscible Mo/Cu system by irradiation damage alloying (IDA)

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Journal of Materials Science & Technology 2018年第4期34卷 689-694页

作者： Jinlong Du Yuan Huang chan Xiao Yongchang Liu Tianjin Key Laboratory of Composite and Functional Materials School of Material Science and Engineering Tianjin University

For the immiscible Mo/Cu system with a positive heat of mixing （△Hm 〉 0）, building metallurgical bonding interfaces directly between immiscible Mo and Cu and preparing Mo/Cu laminar metal matrix composites （LMMCs） are very difficult. To solve the problem, a new alloying method for immiscible systems, which is named as irradiation damage alloying （IDA）, is presented in this paper. The IDA primarily consists of three steps. Firstly, Mo is damaged by irradiation with multi-energy （186, 62 keV） Cu ion beams at a dose of 2× 1017 ions/cm2. Secondly, Cu layers are superimposed on the surfaces of the irradiation-damaged Mo to obtain Mo]Cu laminated specimens. Thirdly, the irradiation damage induces the diffusion alloying between Mo and Cu when the laminated specimens are annealed at 950 ℃ in a protective atmosphere. Through IDA, Mo/Cu LMMCs are prepared in this paper. The tensile tests carried out for the Mo/Cu LMMCs specimens show that the Mo/Cu interfaces constructed via IDA have high normal and shear strengths. Additionally, the microstructure of the Mo/Cu interface is characterized by High Resolution Transmission Electron Microscopy （HRTEM）, X-ray diffraction （XRD） and Energy Dispersive X-ray （EDX） attached in HRTEM. The microscopic characterization results show that the expectant diffusion between Mo and Cu occurs through the irradiation damage during the process of IDA. Thus a Mo/Cu metallurgical bonding interface successfully forms. Moreover, the microscopic test results show that the Mo/Cu metallurgical interface is mainly constituted of crystalline phases with twisted and tangled lattices, and amorphous phase is not observed. Finally, based on the positron annihilation spectroscopy （PAS） and HRTEM results, the diffusion mechanism of IDA is discussed and determined to be vacancy assisted diffusion.

关键词： Mo/Cu immiscible system Irradiation damage alloying Metallurgical bonding interface Ion implantation Laminar metal matrix composites

The blueberry(iron nodule)from the Shark Bay area, Western Australia and its implication to the genetic environments of iron nodules on Mars

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Science China Earth Sciences 2016年第3期59卷 640-650页

作者： LI Jun chan Lung Sang LI Yi Liang Department of Earth Sciences The University of Hong Kong

Fist-sized iron nodules, extensively found on the ground of Western Australia, were investigated by element analysis(XRF, ICP-MS and ICP-AES), electron microscopes, X-ray diffraction and M?ssbauser spectroscopy. Loosely-packed pisoidic structures of a few to >10 mm in size were observed in the cross-section of nodules. Chemically, the nodules are majorly made of O, Si, Fe and Al, and share similar REE pattern with the loess sourced Greatford concretions from New Zealand. Angular quartz particles, nano-sized goethite and hematite are found to be the major mineral phases. Other minerals, such as detrital zircon, barite and Ce-containing particles can also be observed but of very low abundance. No detectable carbonate or amorphous silica implies that these nodules have experienced little underground fluid alteration. The quartz particles showing particularly three sections of fractal size-distributions, together with their extensive broken features and conchoidal fractures, strongly suggest in situ fragmentation of the host rock with minimum later dynamic sorting. These observations indicate the genetic environment of those nodules is always close to the surface of the tectonically stable ground since their formation. Because of the similarity of climatic and geological features, the genesis and preservation environment of these nodules in Western Australia may provide clues on the formation of Martian iron concretions.

关键词： Iron nodules Western Australia Fractal dimensions In situ fragmentation Mars

Computation of Quantum Bound States on a Singly Punctured Two-Torus

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Chinese Physics Letters 2013年第1期30卷 17-20页

作者： chan Kar-Tim Hishamuddin Zainuddin Saeid Molladavoudi Department of Physics Faculty of ScienceUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Laboratory of Computational Sciences and Mathematical Physics Institute for Mathematical ResearchUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia

We study a quantum mechanical system on a singly punctured two-torus with bound states described by the Maass waveforms which are eigenfunctions of the hyperbolic Laplace–Beltrami *** the discrete eigenvalues of the Maass cusp form are not known analytically,they are solved numerically using an adapted algorithm of Hejhal and Then to compute Maass cusp forms on the punctured *** report on the computational results of the lower lying eigenvalues for the punctured two-torus and find that they are *** also visualize the eigenstates of selected eigenvalues using GridMathematica.

关键词： torus states hyperbolic

ON NETWORK-BASED KERNEL METHODS FOR PROTEIN-PROTEIN INTERACTIONS WITH APPLICATIONS IN PROTEIN FUNCTIONS PREDICTION

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Journal of Systems Science & Complexity 2010年第5期23卷 917-930页

作者： Limin LI Waiki CHING Yatming chan Hiroshi MAMITSUKA Department of Mathematics Xi'an Jiaotong University Xi'an 710049 China Advanced Modeling and Applied Computing Laboratory Department of Mathematics The University of Hong Kong Pokfularn Road Hong Kong China Bioinformatics Center Institute for Chemical Research Kyoto University Gokasho Uji Kyoto 611-0011 Japan

Predicting protein functions is an important issue in the post-genomic era. This paper studies several network-based kernels including local linear embedding （LLE） kernel method, diffusion kernel and laplacian kernel to uncover the relationship between proteins functions and protein-protein interactions （PPI）. The author first construct kernels based on PPI networks, then apply support vector machine （SVM） techniques to classify proteins into different functional groups. The 5-fold cross validation is then applied to the selected 359 GO terms to compare the performance of different kernels and guilt-by-association methods including neighbor counting methods and Chi-square methods. Finally, the authors conduct predictions of functions of some unknown genes and verify the preciseness of our prediction in part by the information of other data source.

关键词： Diffusion kernel kernel method Laplacian kernel local linear embedding (LLE) kernel protein function prediction support vector machine.