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Science China(technological Sciences) 2009年第1期52卷 198-203页

作者： S. SUMAtHI S. BHAtIA K.t. lee A. R. MOHAMED School of Chemical Engineering Engineering Campus Universiti Sains Malaysia 14300 Nibong Tebal Pulau Pinang

this study examined the individual and simultaneous adsorption of SO{in{itx}} (SO{in{it2}}) and NO{in{itx}} (NO-NO{in{it2}}) on activated carbon prepared from waste palm shell. the adsorption process was examined in a fixed bed reactor at low temperatures (100\2-300\dgC). For individual adsorption without any catalytic activation, SO{in{itx}} showed good adsorption whereas NO{in{itx}} was very much poor. In the simultaneous adsorption of SO{in{itx}} and NO{in{itx}}, SO{in{itx}} showed greater adsorption affinity than NO{itx}. For palm shell activated carbon (PSAC) impregnated with metal catalyst (Ni and Ce) the concentration adsorbed profile showed that the amount of SO{in{itx}} adsorbed decreased regularly, while the amount of the adsorbed NO{in{itx}} increased irregularly. the properties of the pure and impregnated PSAC were analyzed by BEt, SEM and EDX. these investigations indicated that PSAC impregnated with metal catalyst is the determining factor in the adsorption of SO{in{itx}} and NO{in{itx}} simultaneously.

关键词： palm shell activated carbon flue gas SO_x NO_x

Hurricane disturbances, tree diversity, and succession in North Carolina Piedmont forests, USA

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Journal of Forestry Research 2019年第1期30卷 219-231页

作者： Weimin Xi Robert K.Peet Michael t.lee Dean L.Urban Department of Biology University of North Carolina at Chapel Hill Department of Biological and Health Sciences Texas A & M University-Kingsville the Nicholas School of the Environment Duke University

Windthrow plays a critical role in maintaining species diversity in temperate forests. Do large-scale strong wind events(i.e., tropical cyclones, including hurricanes,typhoons and severe cyclonic storms) increase tree diversity in severely damaged forest areas? Do hurricanes(tropical cyclones that occurs in the Atlantic Ocean and northeastern Pacific Ocean) lead to altered relative abundance of shade-tolerant and shade-intolerant species? Did historic hurricanes alter the succession trajectory of the damaged forests? We used nearly 70-year tree demographic data to assess the effects of two major hurricanes on woody species diversity in Piedmont forests, North Carolina, USA. Species richness(S) and Shannon–Wiener's diversity index(H') were used to evaluate the changes in tree diversity. the changes in composition were assessed with Nonmetric Multidimensional Scaling. the pre-hurricane successional phase can strongly influence both the damage severity and subsequent responses. Although there is often an immediate drop in diversity following a hurricane, understory tree diversity quickly increases to levels that exceed those prior to the disturbance. this leads to an increase in diversity in stands that were substantially damaged. Hurricanes significantly decrease the dominance of shade-intolerant canopy species while increasing preestablished, more shade-tolerant species. We conclude that large, and infrequent hurricanes help to maintain local tree diversity, but also accelerate the increase in dominance of understory species such as red maple and beech.

关键词： Wind disturbance tree species diversity Plant succession Disturbance-diversity relationship Piedmont forests

An Interface-Capturing Method for Resolving Compressible two-Fluid Flows with General Equation of State

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Communications in Computational Physics 2009年第10期6卷 1137-1162页

作者： t.S.lee J.G.Zheng S.H.Winoto Department of Mechanical Engineering National University of SingaporeSingapore 119260

In this study,a stable and robust interface-capturing method is developed to resolve inviscid,compressible two-fluid flows with general equation of state(EOS).the governing equations consist of mass conservation equation for each fluid,momentum and energy equations for mixture and an advection equation for volume fraction of one fluid *** of pressure equilibrium across an interface is used to close the model ***-Hancock scheme is extended to construct input states for Riemann problems,whose solutions are calculated using generalized HLLC approximate Riemann *** mesh refinement(AMR)capability is built into hydrodynamic *** resulting method has some ***,it is very stable and robust,as the advection equation is handled ***,general equation of state can model more materials than simple EOSs such as ideal and stiffened gas EOSs for *** addition,AMR enables us to properly resolve flow features at disparate ***,this method is quite simple,time-efficient and easy to implement.

关键词： MUSCL-Hancock scheme adaptive mesh refinement compressible two-fluid flows general equation of state

η-production on the proton via electromagnetic and hadronic probes

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Chinese Physics C 2009年第12期33卷 1175-1182页

作者： B. Saghai J. Durand B. Julia-Diaz 何军 t.-S. H. lee t. Sato Institut de Recheche sur les lois Fondamentales de l’Univers DSM/Irfu CEA-Saclay 91191 Gif-sur-Yvette France 2. Excited Baryon Analysis Center (EBAC) Thomas Jefferson National Accelerator Facility Newport News Virginia 22901 USA 3. Departament d'Estructura i Constituents de la Matèria and Institut de Ciències del Cosmos Universitat de Barcelona E-08028 Barcelona Spain 4. Institute of Modern Physics Chinese Academy of Sciences Physics Division Argonne National Laboratory Argonne Illinois 60439 USA Department of Physics Osaka University Toyonaka Osaka 560-0043 Japan

the reactions π-p→ηn and γp→ηp are investigated within a dynamical coupled-channels model of meson production reactions in the nucleon resonance region. the meson-baryon channels included are πN, ηN, π-, σN, and ρN. the direct η-photoproduction process is studied within a formalism based on a chiral constituent quark model approach, complemented with a one-gluon-exchange mechanism, to take into account the breakdown of the SU(6)O(3) symmetry. In the models search, the following known nucleon resonances are embodied: S11(1535), S11(1650), P11(1440), P11(1710), P13(1720), D13(1520), D13(1700), D15(1675), and F15(1680). Data for the π-p→ηn reaction from threshold up to a total center-of-mass energy of W ≈ 2 GeV are satisfactorily reproduced. For the photoproduction channel, two additional higher mass known resonances, P13(1900) and F15(2000), are also considered. However, reproducing the data for γp→ηp requires, within our approach, two new nucleon resonances, for which we extract mass and width.

关键词： multichannel scattering meson production baryon resonances

Acoustic Emission Monitoring and Microscopic Investigation of Cracks in ERCuNi Cladding

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Journal of Materials Science & technology 2003年第3期19卷 201-205页

作者： S.P.Lu O.Y.Kwon K.J.lee t.B.Kim Department of Mechanical Engineering Inha University253 Yonghyun-dongInchon 402-751KoreaDepartment of Mechanical EngineeringInha University253 Yonghyun-dongInchon 402-751KoreaDepartment of Mechanical EngineeringInha University253 Yonghyun-dongInchon 402-751KoreaDepartment of Mechanical EngineeringInha University253 Yonghyun-dongInchon 402-751Korea

A corrosion resistant CuNi cladding was deposited on SM45C (equivalent to AISI1045) substrate by DC inverse arc welding. During the welding process, a three channel acoustic emission (AE) monitoring system was applied to detect the crack signals generating from both the cladding process and after cladding. Characteristics of the welding crack signal and noise signal had been analyzed systematically. Based on the record time of the signal, the solidification crack and delayed crack were distinguished. By two-dimensional AE source location, the crack position was located, and then investigated by scanning electron microscopy (SEM). Results showed that the AE system could detect the welding crack with high sensitivity and the two-dimensional source location could accurately determine the crack position. Microstructures of the cladding and heat affected zone (HAZ) were examined. Dendrites in the cladding and coarse grains in the HAZ were found.

关键词： Cladding Acoustic emission monitoring Crack CuNi alloy

Influence of the Feed Gas Composition on the Fischer-tropsch Synthesis in Commercial Operations

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Journal of Natural Gas Chemistry 2007年第4期16卷 329-341页

作者： theo lee R & D Center Headwaters technologies Innovation Group 1501 New York AvenueTrentonNew JerseyUSA

Key technical challenges relating to the Fischer-tropsch （F-t） synthesis applied in the commercialization of coal/gas-to-liquids （CtL/GtL） technologies have been reviewed. Based on the experiences accumulated from pilot plant, semi-work test and lab researches, the influences of the H2/CO ratio and the CO2 in the feed gas on the F-t process as well as on CtL/GtL complex in terms of product yields, energy efficiency and carbon utilization efficiency have been studied. Being contrary to the current design schemes for F-t process using the coal derived syngas and the iron-based cata lyst, it is suggested to feed the F-t synthesis unit with a syngas having a H2/CO ratio of 0.5 and then adjusting to 1.4 via the recycling process. As a result, the carbon efficiency of the whole plant could be reached to as high as 50%. For the issue of CO2 addition to the feed gas, it is proved that only a diluting role is played under the current commercial slurry phase F-t process.

关键词： Fischer-tropsch synthesis gas-to-liquids feed gas composition, carbon efficiency

Effects of Yttrium-90 selective internal radiation therapy on non-conventional liver tumors

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World Journal of Gastroenterology 2015年第27期21卷 8271-8283页

作者： Andrew Kuei Sammy Saab Sung-Ki Cho Stephen t Kee Edward Wolfgang lee Division of Interventional Radiology Department of Radiology UCLA Medical Center David Geffen School of Medicine at UCLA Los Angeles Department of Medicine Division of Hepatology Pfleger Liver Institute University of California at Los Angeles Los Angeles Division of Interventional Radiology Department of Radiology Samsung Medical Center Sungkyunkwan University School of Medicine

the liver is a common site of metastasis, with essentially all metastatic malignancies having been known to spread to the liver. Nearly half of all patients with extrahepatic primary cancer have hepatic metastases. the severe prognostic implications of hepatic metastases have made surgical resection an important first line treatment in management. However, limitations such as the presence of extrahepatic spread or poor functional hepatic reserve exclude the majority of patients as surgical candidates, leaving chemotherapy and locoregional therapies as next best options. Selective internal radiation therapy(SIRt) is a form of catheter-based locoregional cancer treatment modality for unresectable tumors, involving trans-arterial injection of microspheres embedded with a radioisotope Yttrium-90. the therapeutic radiation dose is selectively delivered as the microspheres permanently embed themselves within the tumor vascular bed. Use of SIRt has been conventionally aimed at treating primary hepatic tumors(hepatocellular carcinoma) or colorectal and neuroendocrine metastases. Numerous reviews are available for these tumor types. However, little is known or reviewed on non-colorectal or nonneuroendocrine primaries. therefore, the aim of this paper is to systematically review the current literature to evaluate the effects of Yttrium-90 radioembolization on non-conventional liver tumors including those secondary to breast cancer, cholangiocarcinoma, ocular and percutaneous melanoma, pancreatic cancer, renal cell carcinoma, and lung cancer.

关键词： Liver metastases Breast cancer Melanoma Cholangiocarcinoma Radioembolization Selective internal radiation therapy transarterial radioembolization Yttrium-90

Synthesis and mesomorphic evaluation of new calamitic liquid crystals containing benzothiazole core

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Chinese Chemical Letters 2011年第5期22卷 619-622页

作者： teck Ming Koh Sie tiong Ha teck Leong lee Siew Ling lee Guan Yeow Yeap Hong Cheu Lin Ramesh t.Subramaniam Department of Science Faculty of Engineering & ScienceUniversiti Tunku Abdul RahmanJln Genting KlangSetapak53300 Kuala Lumpur.Malaysia Department of Chemistry National University of SingaporeSingapore 117543Singapore Department of Chemical Science Faculty of ScienceUniversiti Tunku Abdul RahmanJln UniversitiBandar Barat31900 KamparPerakMalaysia Ibnu Sina Institute for Fundamental Science Studies Universiti Teknologi Malaysia81310 UTM SkudaiJohorMalaysia Liquid Crystal Research Laboratory School of Chemical SciencesUniversiti Sains Malaysia11800 MindenPenangMalaysia Department of Materials Science & Engineering National Chiao Tung UniversityHsinchu 300Taiwan Center for Ionics University Malaya Department of Physics Faculty of ScienceUniversity of Malaya50603 Kuala LumpurMalaysia

the design and synthesis of new calamitic benzothiazole-based liquid crystals,2-[4-（4-alkyloxybenzoyloxy）-phenyl]ben-zothiazoles are *** target compound was characterized using spectroscopic techniques,such as Ft-IR,NMR（~1H and ^（13）C）,microanalysis and *** liquid crystalline behaviours of these compounds were thoroughly examined by differential scanning calorimetry and polarizing optical microscope *** materials exhibited enantiotropic nematic phase with high thermal stability（168℃）.Smectic A phase starts to emerge as monotropic（metastable） phase from C10 member and changes into enantiotropic（stable） phase from C12 and persists up to C16 members.

关键词： Benzothiazole Alkoxy chain Nematic Smectic A Liquid crystal

A modular microfluidic system based on a multilayered configuration to generate large-scale perfusable microvascular networks

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Microsystems & Nanoengineering 2021年第1期7卷 63-75页

作者： tao Yue Da Zhao Duc t.t.Phan Xiaolin Wang Joshua Jonghyun Park Zayn Biviji Christopher C.W.Hughes Abraham P.lee Department of Biomedical Engineering University of CaliforniaIrvineCAUSA School of Mechatronic Engineering and Automation Shanghai UniversityShanghaiChina Department of Molecular Biology and Biochemistry University of CaliforniaIrvineCAUSA Department of Micro/Nano Electronics Shanghai Jiao Tong UniversityShanghaiChina National Key Laboratory of Science and technology for Micro/Nano Fabrication Shanghai Jiao Tong UniversityShanghaiChina Key Laboratory for thin Film and Micro Fabrication of the Ministry of Education Shanghai Jiao Tong UniversityShanghaiChina Department of Electrical Engineering and Computer Science University of CaliforniaIrvineCAUSA. Department of Applied Mathematics-Biology Brown UniversityProvidenceRIUSA. Department of Mechanical and Aerospace Engineering University of CaliforniaIrvineCAUSA

the vascular network of the circulatory system plays a vital role in maintaining homeostasis in the human *** this paper,a novel modular microfluidic system with a vertical two-layered configuration is developed to generate largescale perfused microvascular networks in *** two-layer polydimethylsiloxane(PDMS)configuration allows the tissue chambers and medium channels not only to be designed and fabricated independently but also to be aligned and bonded *** method can produce a modular microfluidic system that has high flexibility and scalability to design an integrated platform with multiple perfused vascularized tissues with high *** medium channel was designed with a rhombic shape and fabricated to be semiclosed to form a capillary burst valve in the vertical direction,serving as the interface between the medium channels and tissue *** and anastomosis at the vertical interface were successfully achieved by using different combinations of tissue chambers and medium *** large-scale microvascular networks were generated and quantified in terms of vessel length and *** leakage of the perfused 70-kDa FItC-dextran confirmed the lumenization of the microvascular networks and the formation of tight vertical interconnections between the microvascular networks and medium channels in different structural *** platform enables the culturing of interconnected,large-scale perfused vascularized tissue networks with high density and scalability for a wide range of multiorgan-on-a-chip applications,including basic biological studies and drug screening.

关键词： interconnection networks configuration

Comparative Study on Shearing Edge Quality Influence of the Change of tool Geometry in Fine-Blanking for Non-homogeneous Materials

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厦门大学学报（自然科学版） 2002年第S1期41卷 117-118页

作者： Y C Leung L C Chan t C lee Department of Industrial and Systems Engineering the Hong Kong Polytechnic UniversityDepartment of Industrial and Systems Engineering the Hong Kong Polytechnic UniversityDepartment of Industrial and Systems Engineering the Hong Kong Polytechnic University Hong Kong ChinaHong Kong ChinaHong Kong China

Excellent quality of shearing edge implies that a s mo oth cutting edge without tearing will be observed on the whole edge surface. thi s is one of the most significant features of the Fine-blanking process. to achi eve such a superb blanking edge quality in fine-blanking, there actually involv es quite a large number of factors, such as blanking speed, processing material, product shape, lubrication and tool geometry, to be considered simultaneously d uring the operation. Nevertheless, the thorough investigations on different effe cts of those critical factors for different kinds of popular and applicable mate rial are rare and limited. thus, the objective of this paper is mainly focused o n the study of the quality influence of tool geometry change in fine-blanking f or non-homogeneous materials. However, the most obvious change of the tool geo metry during the operation will be the essential variation of the nose radius of the punch. this is because the nose radius usually seriously deteriorates with the increasing service period in mass production which eventually causes the ent irely lose of the specific features of the fine-blanking process. therefore, a tailor-made experimental study was carried out to investigate the relationship between the punch nose radius and the shearing edge quality, such as blanked edg e finish, burr height and die-roll height, during fine-blanking for different types of material. Five punches with each specified nose radius (Rp), 0.00 mm, 0.25 mm, 0.50 mm, 0.75 mm and 1.00 mm, and four kinds of blanking material ( Mil d steel SS400, Stainless steel AISI316L, Copper alloy UNSC16200 and Aluminium al loy AA6063 ) were employed throughout the study. Subsequently, features of the s heared edge surfaces and data of each experiment were observed and captured for further analysis in this research. Consequently, findings show that an increase of punch nose radius would produce a higher percentage of fracture of blanked ed ge and increase the

关键词： fine-blanking tool geometry shearing edge qual ity