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Characterization of Ultra Fine Solids(BS) in Athabasca Bitumen

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Chinese Journal of Structural Chemistry 2004年第7期23卷 751-754页

作者：李再峰 Judy KUNG 涂云 Luba S.Kotlyar Keng h.chung College of Chemistry and Molecular Engineering Qingdao University of Science and TechnologyShandong 266042China National Research Council of Canada Institute for Chemical Process andEnvironmental TechnologyMontreal Road CampusOttawaOntarioCanada K1A 0R6 Syncrude Canada Ltd.Edmonton Research Centre9421-17th Avenue EdmontonAlberta Canada T6N 1H4

The ultra fine (<200 nm) inorganic solids (BS) were separated from bitumen which was washed by toluene and centrifugated at 2000 rpm. The result of PAS FTIR and image of TEM showed that the structure of BS particles w... 详细信息

The ultra fine (ds (BS) were separated from bitumen which was washed by toluene and centrifugated at 2000 rpm. The result of PAS FTIR and image of TEM showed that the structure of BS particles was smiliar to that of kaolinite clay. On the surface of BS, both toluene insoluble organic matter and structural Oh group are detected at the same time. The surface characteristics imparted a bi-wettable nature to the BS. As a result, the BS is able to stabilize fine water emulsion in the bitumen phase. The organic matter associated with BS is a possible factor of the fouling on catalyst and equipment.

关键词： ultra fine solids characterization bitumen

dirac Oscillator Under the New Generalized Uncertainty Principle From the Concept doubly Special Relativity

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Communications in Theoretical Physics 2019年第11期71卷 1301-1303页

作者： S.Sargolzaeipor h.hassanabadi W.S.chung Faculty of Physics Shahrood University of TechnologyShahroodIran department of Physics and Research Institute of Natural Science College of Natural ScienceGyeongsang National UniversityJinju 660-701Korea

We discuss one-dimensional dirac oscillator, by using the concept doubly special relativity. We calculate the energy spectrum by using the concept doubly special relativity. Then, we derive another representation that the coordinate operator remains unchanged at the high energy while the momentum operator is deformed at the high energy so that it may be bounded from the above. Actually, we study the dirac oscillator by using of the generalized uncertainty principle version and the concept doubly special relativity.

关键词： dirac equation generalized uncertainty principle doubly special relativity

hydrodesulfurization and hydrodenitrogenation Kinetics of a heavy Gas Oil over NiMo/Al_2O_3 Catalysts

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高校化学工程学报 2005年第6期19卷 762-766页

作者： dUAN Ai-jun XU Chun-ming LIN Shi-xiong chung Keng h State Key Laboratory of heavy Oil Processing University of Petroleum Beijing 102249 China Syncrude Canada Ltd. 9421 - 17 Avenue Edmonton Alberta Canada T6N IH4

The kinetics of Athabasca bitumen derived heavy gas oil over NiMo/Al2O3 catalysts were studied in a JQ-II high-pressure microscale hydrotreator unit under different operation conditions, including temperature, pressure, h/O ratio and LhSV. The multi-parameter models of hydrodesulfurization and hydrodenitrogenation were proposed. The model parameters verify that the hdS and hdN reactions follow 1.5-order and 1.6-order kinetic rules, respectively. The kinetic activation energies of hdN and hdS over Com, hom1 and hom2 show that homemade catalysts exhibit higher activities in hdN than commercial catalyst. Using the multi-parameter kinetic model to predict the contents of sulfur and nitrogen in products is in good agreement with the experimental data.

关键词：加氢脱硫加氢脱氮动力学模型重气油 NiMo/Al2O3催化剂

Effectiveness of air cleaner on mitigating the transmission of respiratory disease in a dental clinic environment

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Building Simulation 2024年第10期17卷 1789-1803页

作者： Gang Yang Yifan Wang Ka chung Chan Kwok Wai Mui Thomas F.Flemmig SThomas Ng Christopher Y.h.Chao Sau chung Fu department of Building Environment and Energy Engineering The Hong Kong Polytechnic UniversityHong KongChina Faculty of dentistry The University of Hong KongHong KongChina department of Architecture&Civil Engineering City University of Hong KongHong KongChina department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong KongChina

In dental clinics with an open floor plan,the risk of patient-to-patient transmission of respiratory disease is a *** dental procedures large amounts of bioaerosol are produced and patients cannot wear personal protective *** paper examines how to effectively deploy air cleaner to reduce the infection risk in dental clinics with an open floor *** locations of air cleaners at various clean air delivery rates(CAdRs)were *** dispersion of bioaerosol was studied through numerical simulations,and risk assessment was performed by a dose-response *** findings indicated that dental patients downstream of the background ventilation have a higher infection risk than those to the left and right of an infected patient(i.e.,the source).The lowest infection risks for the adjacent patients were found when the air cleaner was place opposite to the dentists,i.e.,on the floor at low CAdR levels of 2.2 m^(3)/min or on the bench at CAdR levels of 4.4 m^(3)/min or *** results of this study indicated that air cleaner can mitigate the risk of patient-to-patient transmission of SARS-CoV-2 in dental clinics with an open floor *** CAdR levels determine the optimal placement of air cleaners.

关键词： infection risk air cleaner location dental clinic CFd simulation respiratory disease

Properties Correlations and Characterization of Athabasca Oil Sands-derived Synthetic Crude Oil

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Petroleum Science 2007年第3期4卷 84-90页

作者： Wang Jun Zhao Suoqi Xu Chunming chung Keng h. State Key Laboratory of heavy Oil Processing China University of Petroleum Beijing 102249 China Petrochemical Institute of PetroChina Beijing 10083 China EnergyINet Calgary Alberta Canada

Narrow fractions of Athabasca oil sands-derived synthetic crude oil （SCO） from Canada were obtained by distillation at 20 ℃ to 500 ℃ and characterized. The yield and properties, such as density, refractive index, viscosity, freezing point, sulfur and nitrogen content and UOP K-index, were correlated as a function of boiling temperature （Tb）. The properties of naphtha fractions, jet fuel and diesel fractions could be predicted accurately with the correlations, which are useful for process design considerations, such as optimizing operating conditions of refinery processing units. The other key properties and characteristics of naphtha fractions, jet fuel, diesel and vacuum gas oil were also determined.

关键词： SCO properties correlation characterization

Atomistic investigation of pressure effects on sintering of bimetallic core-shell nanoparticles

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Journal of Materials Science & Technology 2024年第17期184卷 64-74页

作者： Juheon Kim hayoung chung department of Mechanical Engineering Ulsan National Institute of Science and Technology50 Unist-gilUlsan 44919South Korea

Pressure-assisted sintering(PAS)utilizing bimetallic core-shell nanoparticles(CS NPs)has garnered widespread attention for its ability to produce advanced components with excellent thermal and elec-trical conductivities,even at low *** study presents the first investigation into the PAS of bimetallic CS NPs,using Ag-coated Cu material as a representative system,through all-atom molecu-lar dynamics(Md)*** study provides detailed insights into the atomic-scale processes and mechanisms that govern pressure-assisted sintering,elucidating the coalescence phenomena and reveal-ing the significant influence of external *** comparing atomistic behaviors,such as diffusion,migration,and microstructure evolution,between PAS and thermal sintering,a deeper understanding of the underlying mechanisms is ***,the results highlight the importance of considering microstructural characteristics in addition to void fraction assessment for accurately estimating mechani-cal *** study enhances our understanding of sintering methods and offers a new perspective on designing process conditions in the PAS process.

关键词： Core-shell nanoparticles Pressure-assisted sintering Molecular dynamics simulation Many-particle model Microstructure Mechanical properties

New fossil mayflies （Insecta： Ephemeroptera） from the Middle Jurassic of daohugou, Inner Mongolia, China

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Insect Science 2008年第2期15卷 193-198页

作者： Jian-dong huang dong Ren Nina d. Sinitshenkova chung-Kun Shih College of Life Science Capital Normal University Beijing China Palaeontological Institute of the Russian Academy of Sciences MoscowRussia

Abstract Jurassonurus amoenus, a new genus and species of Siphlonuridae s. I. is described from the Middle Jurassic Jiulongshan Formation of the daohugou Village, Shantou Township, Ningcheng County, Inner Mongolia, China. The new species is estab- lished by more than 20 imago and subimago specimens in relatively good condition. detailed description and illustration of the specimens along with a review of fossil Siphlonuridae s. I. are given. Comparing with two known dominant nymph species Fuyous gregarious Zhang and Kluge, 2007 and Shantous lacustri Zhang and Kluge, 2007 from the same locality, we could not find any relationship among them. The new species is another dominant species in daohugou beds.

关键词： new genus new species Ephemeroptera Siphlonuridae fossil daohugou,Middle Jurassic China

Analytical modelling of end thermal coupling in a solid-state laser longitudinally bonded by a vertical-cavity top-emitting laser diode

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Chinese Physics B 2009年第11期18卷 4912-4918页

作者：吴坚 h.d.Summers School of Physics Beijing University of Aeronautics and Astronautics School of Physics and Astronomy Cardiff University

The intrinsic features involving a circularly symmetric beam profile with low divergence, planar geometry as well as the increasingly enhanced power of vertical-cavity surface-emitting lasers （VCSELs） have made the VCSEL a promising pump source in direct end bonding to a solid-state laser medium to form the minimized, on-wafer integrated laser system. This scheme will generate a surface contact pump configuration and thus additional end thermal coupling to the laser medium through the joint interface of both materials, apart from pump beam heating. This paper analytically models temperature distributions in both VCSEL and the laser medium from the end thermal coupling regarding surface contact pump configuration using a top-emitting VCSEL as the pump source for the first time. The analytical solutions are derived by introducing relative temperature and mean temperature expressions. The results show that the end contact heating by the VCSEL could lead to considerable temperature variations associated with thermal phase shift and thermal lensing in the laser medium. however, if the central temperature of the interface is increased by less than 20 K, the end contact heating does not have a significant thermal influence on the laser medium. In this case, the thermal effect should be dominated by pump beam heating. This work provides useful analytical results for further analysis of hybrid thermal effects on those lasers pumped by a direct VCSEL bond.

关键词： solid-state laser end pump thermal coupling vertical-cavity surface-emitting laser

Flow characteristics by particle image velocimetry in liquefied natural gas vaporizer model with several baffles

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Journal of Central South University 2011年第5期18卷 1719-1725页

作者： h.S.chung S.M.Sayeed-Bin-Asad Berkah Fajar Y.h.Shin h.M.Jeong department of Mechanical and Precision Engineering Institute of Marine Industry445 Inpyeong DongTongyeongGyeongsangnamdo650-160Korea department of Mechanical and Precision Engineering Gyeongsang National University445 Inpyeong DongTongyeongGyeongsangnamdo650-160Korea department of Mechanical Engineering University of DiponegoroSemarangIndonesia

Shell-and-tube vaporizers are the most commonly used and dominated types of vaporizers in liquefied natural gas （LNG） realm. due to efficient performance, shell-side flow in this type of vaporizers has received considerable attention and has been investigated extensively. however, the detailed flow structure in the shell needs to be determined for reliable and effective design. Therefore, the objective of this study was to clarify the flow structure in shell by particle image velocimetry （PIV）. Experiments were conducted using two types of model; 15% baffle cut having inlet and outlet positions !n the direction of 90° to the cut and 30% baffle cut having inlet and outlet positions in the direction of 180° to the cut. Each test section is 169 mm in inner diameter and 344.6 mm in length. The flow features were characterized in different baffle cuts with regards to the velocity vector field and velocity distribution. The results show that the flow characteristics of 15% baffle cut type vaporizer are comparable to those of 30% baffle cut type vaporizer.

关键词： particle image velocimetry liquefied natural gas vaporizer vortex turbulence