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Methyl acetate-methanol mixture separation by extractive distillation:Economic aspects

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Frontiers of Chemical Science and Engineering 2018年第4期12卷 670-682页

作者： Elena Graczova Branislav Sulgan samuel Barabas Pavoi Steltenpohl Institute of Chemical and Environmental Engineering Faculty of Chemical and Food Technology Slovak University of Technology in Bratislava81237 BratislavaSlovakia

Methyl acetate is considered low toxicity volatile solvent produced either as a by-product during methanol carbonylation or via acetic acid esterification with methanol. In both cases, pure methyl acetate has to be isolated from the reaction mixture. Simulation of methyl acetate separation from its mixture with methanol by extraction distillation was carried out in ASPEN+ software. In total three case studies were assumed using two different extraction solvents and two solvent regeneration strategies. In case A, novel extraction solvent 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ionic liquid, was considered. Raw material separation was achieved in an extraction distillation column while the solvent regeneration was accomplished in a second distillation column in this case. In case study B, the same extraction solvent was used; however, its regeneration was carried out in a single-effect evaporator. Dimethyl sulfoxide was the second extraction solvent selected. Its use in methyl acetate-methanol separation is presented in case study C. As high purity of dimethyl sulfoxide was required for the methyl acetate-methanol azeotrope breaking, its regeneration was carried out in the second distillation column only. To simulate the ternary methyl acetate–methanol–extraction solvent mixtures separation, vapor–liquid equilibrium was predicted based on the NRTL equation. Further, unknown properties of the considered ionic liquid and variation of these properties with temperature were predicted and introduced into the ASPEN+ components properties database. Based on these data, optimum operation parameters of the respective separation equipment were established. In all case studies, the same condition had to be fulfilled, namely minimum methyl acetate content in the distillate from the extraction distillation column of 99.5mol-%. Results of simulations using the respective optimum operation parameters were employed in the economic evaluation of the three separation unit

关键词： methyl acetate 1-ethyl-3-methylimidazolium trifluoromethanesulfonate extraction distillation dimethyl sulfoxide economic evaluation

Thermodynamic analysis for a third grade fluid through a vertical channel with internal heat generation

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Journal of Hydrodynamics 2015年第2期27卷 264-272页

作者： ADESANYA samuel O. MAKINDE Oluwole D. Department of Mathematical Sciences Redeemer's University Faculty of Military Science Stellenbosch University

This paper makes the thermodynamic analysis in forced convective flow of a third grade fluid through a vertical channel. Due to the reactive nature of the fluid, the effect of internal heat generation is considered and assumed to be a linear function of temperature. The coupled nonlinear dimensionless ordinary differential equations governing the fluid flow are solved by using the Adomian decomposition method（ADM）. The effects of various physical parameters such as third grade material parameter, buoyancy parameter and heat generation parameter on the thermal structure of flow are presented and discussed.

关键词： energy conservation vertical channel third grade fluid internal heat generation Adomian decomposition method(ADM)

A geometry-based framework for modeling the complexity of origami folding

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Theoretical & Applied Mechanics Letters 2021年第3期11卷 115-124页

作者： samuel Schulman Xin Ning Department of Aerospace Engineering The Pennsylvania State UniversityUniversity ParkPennsylvania 16802USA

This paper presents a quantitative framework to analyze the complexity of folding origami structures from flat *** efforts have realized intricate origami patterns with desired functions such as mechanical properties,packaging efficiency,and deployment ***,the complexity associated with the manufacturing or folding of origami patterns has not been *** how difficult origami structures are to make,and how much time they require to form is crucial information to determining the practical feasibility of origami designs and future applications such as robotic origami assembly in *** this work,we develop this origami complexity metric by modeling the geometric properties and crease formation of the origami structure,from which it outputs crease and pattern complexity values and a prediction of the time to complete the pattern assembly,based on the characteristics of the *** framework is experimentally validated by fabricating various Miura-ori origami paper models.

关键词： Origami folding Framework Miura-ori

Field report:Sailing around the exhumed roots of the Mesozoic Patagonian paleo-accretionary wedge(Diego de Almagro Island,Chile)

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Geoscience Frontiers 2018年第5期9卷 1591-1594页

作者： samuel Angiboust Jesus Munoz Institut de Physique du Globe de Paris Sorbonne Paris CitéUniversity Paris DiderotCNRSF-75005ParisFrance GFZ German Research Centre for Geosciences D-14473PotsdamGermany Carrera de Geología Universidad Andres BelloSazie2119SantiagoChile

We undertook a boat expedition to explore the geological framework of a very remote, lesser-known island, in the Chilean Patagonia: the Diego de Almagro Island(latitude S51°330'). This uninhabited, ca.400 km^2 Island is one of the very rare exposures of the Mesozoic accretionary subduction complex along the Chilean margin. Unstable weather, strong winds, steep topography, and very dense vegetation make an on-land mission difficult. Careful preparation based on high-resolution satellite images is advised to optimize shore access and minimize risks of injury. Despite a relatively important degree of regional reequilibration of metamorphic assemblages due to sluggish exhumation through the forearc crust, our results have shown that the island is composed of a nappe stack of ocean-floor derived slivers of metasedimentary units that exhibit very different pressure-temperature-time paths during burial by subduction under the Chilean margin and subsequent exhumation. These rocks are witness to a complex thermal evolution of the subduction zone between Jurassic and Cretaceous times from granulite facies to blueschist facies conditions as well as multiple episodes of accretion at ca. 35 -40 km in depth for almost100 Ma over the Mesozoic era.

关键词： Patagonia Accretionary wedge Blueschists Subduction Chile

EXTENDED WARRANTY STRATEGIES FOR ONLINE SHOPPING SUPPLY CHAIN WITH COMPETING SUPPLIERS CONSIDERING COMPONENT RELIABILITY

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Journal of Systems Science and Systems Engineering 2017年第6期26卷 753-773页

作者： Xinghong Qin Qiang Su samuel H. Huang School of Economics and Management Tongji University Shanghai China School of Business Planning Chongqing Technology and Business University Chongqing China Department of Mechanical and Materials Engineering University of Cincinnati Cincinnati USA

This article presents the issue of extended warranty and management strategies in a three-echelon competing online shopping supply chain with price- and base warranty period-dependent demand. We employ game theory to develop decision models to explore the interactions between component suppliers and the manufacturer, as well as competition between two component suppliers. Products and extended warranty are sold by an online store, which is the leader in the Stackelberg game. Two scenarios are considered： either the manufacturer offers a prepaid extended warranty to customers or doses not. In each scenario, base warranties are assumed to be bundled with products. Our results show that when the manufacturer＇s repair costs change in a proper range, providing extended warranty can benefit both the manufacturer and the online store; otherwise, the manufacturer has no incentive to offer the extended warranty. Reducing repair costs, improving component reliability, or shortening the base warranty period allows the manufacturer to realize significantly better value of the extended warranty. High component reliability benefits both the manufacturer and the online store, with the manufacturer reaping more benefit. Extending the length of the base warranty adversely affects profit of the manufacturer and the value of the extended warranty.

关键词： Extended warranty online shopping supply chain game theory online shopping

A correction of the 2D KdV equation of Djordjevic & Redekopp in exponentially stratified fluid

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Acta Mechanica Sinica 2005年第4期21卷 346-352页

作者： Zhaoting Xu Guojin Shen samuel Shan-pu Shen Institute Of Physical Oceanography and Physical Oceanography Laboratory Ocean University of China Qingdao 266003 China Department of Mathematics and Statistics Science University of Alberta Edmonton Alberta T6G 2G 1 Canada

To further study the nal solitons on the continental fission laws of initial intershelf/slope, we rederive and correct the 2D KdV equation of Djordjevic ＆ Redekopp for exponentially stratified fluid （or ocean） and with twodimensional topography. Through a combination of theoretical study and numerical experiments, we show that solitons in the odd vertical modes can fission. However, because of the corrections, the fission conditions are different from those of Djordjevic ＆ Redekopp. The even modes cannot fission unless the initial internal solitons propagate from shallow sea to deep sea. This conclusion is entirely opposite to that of Djordjevic ＆ Redekopp.

关键词： Internal wave Soliton Fission 2D KdV equation

An evaluation of digital elevation modeling in GIS and Cartography

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Geo-Spatial Information Science 2014年第2期17卷 139-144页

作者： Bola AYENI Kayode Julius samuel Department of Geography University of IbadanIbadanNigeria Department of Geography&Resource Management Osun State UniversityOkukuNigeria

This study considers seven commonly used surface fitting methods within Golden Software and ArcGIS^(TM) *** grid sizes of 68 rows by 100 columns(6800 grids)and 680 rows by 1000 columns(680,000 grids)and 294,208 elevation points covering the entire landmass of Nigeria,the study evaluates the performance of these methods in terms of execution time and faithfulness in the representation of the spatial *** show marked differences in time taken to execute the fitting and that Inverse Distance,the Natural Neighbor,the Nearest Neighbor,and Triangulation with Linear Interpolation seem to give the highest level of correspondence or faithfulness.

关键词： image surface fitting digital elevation modelling GIS cartography

On Models of Nonlinear Evolution Paths in Adiabatic Quantum Algorithms

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Communications in Theoretical Physics 2013年第1期59卷 22-26页

作者：孙杰路松峰 samuel L.Braunstein School of Computer Science Huazhong University of Science and Technology Department of Computer Science University of York

In this paper,we study two different nonlinear interpolating paths in adiabatic evolution algorithms for solving a particular class of quantum search problems where both the initial and final Hamiltonian are one-dimensional projector Hamiltonians on the corresponding ground *** the overlap between the initial state and final state of the quantum system is not equal to zero,both of these models can provide a constant time speedup over the usual adiabatic algorithms by increasing some another corresponding "complexity".But when the initial state has a zero overlap with the solution state in the problem,the second model leads to an infinite time complexity of the algorithm for whatever interpolating functions being applied while the first one can still provide a constant running ***,inspired by a related reference,a variant of the first model can be constructed which also fails for the problem when the overlap is exactly equal to zero if we want to make up the "intrinsic" fault of the second model - an increase in *** concrete theorems are given to serve as explanations why neither of these two models can improve the usual adiabatic evolution algorithms for the phenomenon *** just tell us what should be noted when using certain nonlinear evolution paths in adiabatic quantum algorithms for some special kind of problems.

关键词： adiabatic evolution nonlinear evolution paths quantum computing

Pharmacogenomics of EGFR-targeted therapies in non-small cell lung cancer:EGFR and beyond

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Chinese Journal of Cancer 2015年第4期34卷 149-160页

作者： Christopher Delaney samuel Frank R Stephanie Huang Biological Sciences Division University of Chicago Department of Medicine University of Chicago The Affiliated Hospital School of MedicineNingbo University

Commonly observed aberrations in epidermal growth factor receptor(EGFR) signaling have led to the development of EGFR-targeted therapies for various cancers,including non-small cell lung cancer(NSCLC).EGFR mutations and overexpression have further been shown to modulate sensitivity to these EGFR-targeted therapies in NSCLC and several other types of ***,it is clear that mutations and/or genetic variations in EGFR alone cannot explain all of the variability in the responses of patients with NSCLC to EGFR-targeted *** instance,in addition to EGFR genotype,genetic variations in other members of the signaling pathway downstream of EGFR or variations in parallel receptor tyrosine kinase(RTK) pathways are now recognized to have a significant impact on the efficacy of certain EGFR-targeted *** this review,we highlight the mutations and genetic variations in such genes downstream of EGFR and in parallel RTK ***,the directional effects of these pharmacogenetic factors are discussed with a focus on two commonly prescribed EGFR inhibitors:cetuximab and *** results of this comprehensive review can be used to optimize the treatment of NSCLC with EGFR ***,they may provide the rationale for the design of subsequent combination therapies that involve the inhibition of EGFR.

关键词：表皮生长因子受体非小细胞肺癌药物基因组学 EGFR 靶向治疗信号传导途径受体酪氨酸激酶遗传变异