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Sol–gel La2O3–ZrO2 mixed oxide catalysts for biodiesel production

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Journal of Energy Chemistry 2018年第2期27卷 565-572页

作者： Daniela Salinas Catherine sep.lveda néstor Escalona J.L.GFierro Gina Pecchi Departamento de Fisicoquimica. Facultad de Ciencias Quimicas Universidad de Concepcion Post Office 160-C Concepcion Chile Departamento de Quimica Facultad de Ciencias Universidad del Biobio Post Office 5-C Concepcion Chile Departamento Ingenieria Quimica y Bioprocesos Escuela de lngenieria Pontificia Universidad Catolica de Chile Avda. Vicuria Mackenna 4870 Maeul Santiago 7820436 Chile Centro de Investigacion en nanotecnolagia y Materiales Avanzados (CIEn-UC) Pontificia Universidad Catolica de Chile Post Office 306 Santiago Chile Departamento de Quimica Fisica Facultad de Quimica Pontificia Universidad Catolica de Chile Post Offce 306 Santiago Chile Instituto de Catalisis y Petroleoquimica CSIC 28049 Madrid. Espana

Different La2O3 contents（0, 1, 2, 3, and 5 wt%） were used to prepared La2O3-ZrO2 mixed oxides calcined at 600 ℃ by the sol-gel method. The catalytic activity was measured as biodiesel production from canola oil through a transesterification reaction. The characterization results indicate that the La2O3 monolayer formation and extent of basicity of m-ZrO2 have a large influence on biodiesel *** biodiesel conversion（56% at 4 h） was obtained with the 3% La2O3-ZrO2 catalyst in the presence of basic sites and the formation of a monolayer of La2O3. The decrease in the catalytic activity for 5% La2O3-ZrO2 resulted from the loss of active sites on the catalyst because of agglomeration, which was suggested by XPS and the isoelectric point. The kinetic data fit to a pseudo-first order constant, and the largest kinetic constant corresponds to 3% La2O3-ZrO2, currently the largest heterogeneous non-alkaline metal catalyst reported for a transesterification reaction.

关键词： La2O3 -ZrO2 Sol-gel Biodiesel Canola oil Transesterification

nUMERICAL MODELLInG OF THE WATER AIR TWO PHASE JET InTO A PLUnGE POOL

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Journal of Hydrodynamics 1999年第3期11卷 1-5页

作者： Xu Wei lin, Wang Wei, Yang Yong quan, Chen Jian kang State Key Hydraulic Lab. of High Speed Flows, Sichuan University, Chengdu 610065, P.R.China (Received sep. 23, 1997)

The areated jet into a plunge pool is simulated by using a mathematical model of water air two phase flow. The equation of air mass fraction is employed together with the equations of the algebraic stresses model (ASM) of water air mixture to give the distributions of the air concentration and other flow parameters. The computational air concentration distribution is in agreement with the experimental data.

关键词： numerical modelling two phase jet

nUMERICAL AnALYSIS OF SIDE DISCHARGES InTO A CHAnnEL FLOW USInG An RnG k^(-ε)MODEL

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Journal of Hydrodynamics 1999年第3期11卷 44-54页

作者： Wang Xiao jian Cheng Liang Deparment of Civil Engineering, The University of Western Australia, nedlands 6907, Western Australia Cui Li Department of Civil Engineering, Dalian University of Technology, Dalian 116024, P.R.China (Received sep.

Side discharge into a channel flow is numerically simulated using an RnG based k ε turbulence model. It is shown that the results of the recirculation zone obtained using the RnG k ε model generally agree better with the experimental results compared with those by the standard k ε model. The reason for the improvement of the results obtained using the RnG k ε model over those by the standard k ε model on this flow is analyzed. The flow at small discharge ratios is thoroughly investigated and it is found that the velocity profile at the jet exit is extremely non uniform at small discharge ratios. It is also found that the degree of the non uniformity decreases as the discharge ratio increases, and is very slight for discharge ratios larger than 2.0. The effects of calculation domain, mesh size, wall functions, bed roughness and discharge ratios on the size of sep.ration zone are also investigated in detail.

关键词： RnG kε model side discharge flow sep.ration zone bed roughness

Signal Demultiplexing from an 8 .2 ×2.5 Gbs OTDM Data Stream Using nOLM:Demonstration and Bit Error Rate Measurement

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Chinese Journal of Lasers 1999年第4期8卷 3-5页

作者： YAO Minyu ZHAnG Jianfeng WU Jian CHEn Minghua WAnG Dapeng LOU Caiyun GAO Yizhi ZHOU Bingkun (Department of Electronic Engineering, Tsinghua University, Beijing 100084, China) Received sep. 24, 1998 Revised manuscript received Jan. 22, 1999 清华大学电子工程系北京 100084 清华大学电子工程系北京

It is presented the experiment of all optical demultiplexing of one 2.5 Gb/s channel from an 8×2.5 Gb/s OTDM data stream using nonlinear optical loop morror with 3 km dispersion shifted fiber. Bit error rate (BER) of the demultiplexed channel is measured. A BER of 10 -11 is achieved and the power penalty is only 1.4 dB when BER is 10 -9 .

关键词： optical time division multiplexing demultiplexing nonlinear optical loop mirror bit error rate

nanogenerator-based bidirectional pressure sensor array and its demonstration in underwater invasive species detection

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nano Research 2023年第9期16卷 11822-11831页

作者： Yunqi Cao Hongyang Shi Xiaobo Tan nelson sep.lveda State Key Laboratory of Industrial Control Technology College of Control Science and EngineeringZhejiang UniversityHangzhou 310027China Department of Electrical and Computer Engineering Michigan State UniversityEast LansingMichigan 48824USA

Lakes areas,which cause catastrophic damages in both commercial fishery and ecological ***,current assessment strategies may pose challenges for lake-wide abundance estimation and non-target anadromous species ***,we demonstrate an efficacious species-specific non-destructive sensing system based on porous ferroelectret nanogenerator for in-situ monitoring of lamprey spawning migration using their unique suction *** show that the porous structure enables a redistribution of surface charges under bidirectional deformations,which allows the detection of both positive and negative *** quasi-piezoelectric effect is further validated by quantitative analysis in a wide pressure range of−50 to 60 kPa,providing detailed insights into transduction working *** reliable lamprey detection,a 4×4-pixel sensor array is developed and integrated with a complementary metal-oxide-semiconductor(CMOS)based signal processing array thus constituting a sensing panel capable of recording oral suction patterns in an underwater environment.

关键词： bidirectional pressure sensing nanogenerators self-powered sensor array ferroelectret invasive species detection

Study on textile waste generation in the undifferentiated municipal solid waste stream in Guimarães,Portugal

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Waste Disposal and Sustainable Energy 2023年第2期5卷 189-203页

作者： Alona Perebynos Dalila sep.lveda Carlos Ribeiro Landscape Laboratory Rua da Ponte RomanaCreixomil4835-095GuimarãesPortugal Environmental and Public Space Division Environmental and Sustainability DepartmentGuimarães City CouncilLargo Cónego JoséMaria Gomes4804-534GuimarãesPortugal

Guimarães is a middle sized city and municipality located in northern *** municipality has committed to reducing the annual amount of undifferentiated municipal solid waste(MSW)from 371 kg/capita in 2021 to 120 kg/capita by 2030 under the Zero Waste Cities Certification *** the municipality of Guimarães,one of the constant fractions of MSW composition is textile waste(TW),which the revised EU Waste Framework Directive requires sep.rate collection by 1 January ***,two indicators of TW generation were analysed to identify waste collection routes with a high level of textile waste generation for the priority implementation of sep.rate collection:TW composition in the undifferentiated MSW stream and TW generation per *** statistical analysis methods were used to process the source data of TW composition in the undifferentiated MSW *** analysis was applied to the data set on TW generation per capita,considering the area typology(urban,rural or mixed)of collection *** was considered that 39%of the industrial sector of Guimarães consists of textile and clothing production and represents small-and medium-sized enterprises,which can affect TW generation in the undifferentiated MSW ***-comparative research was used to define the correlation between TW generation per capita and the economic activity of the textile and clothing industry in the *** a result,applying a multi-disciplinary approach,a project of the Textile Waste Generation Map was presented.

关键词： Textile waste Municipal solid waste Waste generation indicators Waste management Circular economy

A nOn LInEAR AnALYSIS OF TWO PHASE FLOW InSTA BILITY In PARALLEL CHAnnELS OF A BOILInG SYSTEM

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Journal of Hydrodynamics 1999年第3期11卷 36-43页

作者： Zhou Yun long, Cheng Zhuo ming, Cai Hui northeast China Institute of Electric Power Engineering, Jilin 132012, P.R.China (Received sep. 18, 1998)

This paper proposes a non linear mathematical model of two phase flow instability in parallel channels of a boiling system. Close agreement is obtained between calculations based on this model and measurements of the stable boundary in a system of two channels. The model is also applied to the cases of three and four parallel channels.

关键词： parallel channel flow instability mathematical model

RESEARCH AnD PROGRESS OF WEISFOGH MECHAnISM HYDRODYnAMICS

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Journal of Hydrodynamics 1999年第3期11卷 55-60页

作者： Zhang She sheng, Wu Xiu heng, Wan Xian fu Department of Mathematics, Wuhan Transportation Univercity, Wuhan 430063, P.R.China (Received sep. 28, 1998)

Attention is focused on the research and progress of Weis Fogh mechanism hydrodynamics in this paper. We review some physical models and mathematical models of Weis Fogh mechanism, and also describe some analytic me... 详细信息

关键词： Weis Fogh mechanism hydrodynamics mathematical model

Environmental degradation through mining for energy resources:The case of the shrinking Laguna Santa Rosa wetland in the Atacama Region of Chile

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Energy Geoscience 2022年第2期3卷 182-190页

作者： Mohammad Ayaz Alam Rosa sep.lveda Departamento de Geología Facultad de IngenieríaUniversidad de AtacamaAvenida Copayapu 485CopiapoRegion de AtacamaChile

As the world strives to replace fossil fuels with clean energy e reflected by global surge in the number of electric vehicles e the environmental impact of mining all the lithium(Li)needed to enable such a transformation has become a problem in its own *** South America,the biggest problem is the excessive use of water in Li extraction process in one of the driest areas in the *** from causing severe friction over water rights between local communities and mining companies,it puts enormous pressure on the region's fragile and poorly understood wetland *** are one of the most threatened ecosystems on the Earth,despite their great importance as habitats for a vast number of species and corresponding to one of the most productive *** work is the outcome of an investigation on Laguna Santa Rosa's(LSR)vulnerability resulting from ongoing metal mining operations in its surroundings that require a large volume of water extracted from local aquifers,in addition to a high evaporation rate in the *** groundwater-dependent wetland will soon be further vulnerable with the commencement of water-intensive Li mining at Salar de Maricunga,with the extraction project already having an environmental impact study *** of this wetland protected under the Ramsar Convention and home to numerous wildlife species habiting this highland sector of the Andean Cordillera is vital for the associated *** variation in the water surface area of LSR has been deciphered through the application of a Landsat-5 Thematic Mapper(TM)satellite image *** has been done both for the hydrological year 2016e2017 and 1993-2014 period.A decreasing trend in the water surface area of LSR,a hypersaline lake at the southern extreme of Salar de Maricunga,a salt flat in the Atacama Region of Chile,was observed through the study of satellite images between 1993 and 2014,showing shrinking of this ***,this shrinking t

关键词： Laguna Santa Rosa Salar de Maricunga Lithium Water Wetland Ecosystem