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A Comparison of Hydrothermal Aging, SO₂ and Propene Poisoning Effects on NH₃-SCR over Cu-ZSM-5 and Cu-SAPO-34 Catalysts

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Journal of Materials Science and Chemical Engineering 2024年第5期12卷 10-28页

作者： Kouadio Brou Albert Koffi Konan Martin Zran van Eric-Simon Horo Kone Unité de Formation et de Recherche des Sciences et de Technologies (UFR ST) Universit&#233 Alassane Ouattara Bouak&#233 C&#244te d&#8217Ivoire Unité de Formation et de Recherche Environnement (UFR E) Universit&#233 Jean Lorougnon Gu&#233d&#233 Daloa C&#244te d&#8217Ivoire Unité de Formation et de Recherche des Sciences des Structures de la Mati&#232re et de Technologie (UFR SSMT) Abidjan C&#244te d&#8217Ivoire

This study was aimed to investigate the effects of hydrothermal aging, propene and SO2 poisoning on the ammonia-selective catalytic reduction (NH3-SCR) performance of both Cu-SAPO-34 and Cu-ZSM-5. The catalytic activities of fresh, aged and poisoned samples were tested in ammonia-selective catalytic reduction (NH3-SCR) of NOx conditions. The XRD, TG and N2-desorption results showed that the structures of the Cu-SAPO-34 and Cu-ZSM-5 remained intact after 750˚C hydrothermally aged, SO2 and propene poisoned. After hydrothermal aging at 750˚C for 12 h, the NO reduction performance of Cu-ZSM-5 was significantly reduced at lower temperatures, while that of Cu-SAPO-34 was less affected. Moreover, Cu-SAPO-34 catalyst showed high NO conversion with SO2 or propene compared to Cu-ZSM-5. However, Cu-ZSM-5 showed a larger drop in catalytic activity with SO2 or propene compared to Cu-SAPO-34 catalyst. The H2-TPR results showed that Cu2 ions could be reduced to Cu and Cu0 for Cu-ZSM-5, while no significant transformation of copper species was observed for Cu-SAPO-34. Meanwhile, the UV-vis DRS results showed that CuO species were formed in Cu-ZSM-5, while little changes were observed for the Cu-SAPO-34. Cu-SAPO-34 showed high sulfur and hydrocarbon poison resistance compared to Cu-ZSM-5. In summary, Cu-SAPO-34 with small-pore zeolite showed higher hydrothermal stability and better hydrocarbon and sulfur poison resistant than Cu-ZSM-5 with medium-pore.

关键词： Hydrothermal Aging Propene and SO2Poisoning Ammonia-Selective Catalytic Reduction(NH3-SCR) Cu-SAPO-34 Cu-ZSM-5

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什么是伦勃朗真迹?我与伦勃朗研究项目

新美术 2024年第2期45卷 44-121,F0002,I0001,265,F0003页

作者： [荷]恩斯特·范德韦特林柴晓蕾(译) 万木春(校) 不详中国美术学院

1916年,美国铁路大亨、艺术收藏家亨利·克莱·弗里克[Henry Clay Frick,1849-1919]买进伦勃朗的画作《持书的老妇》[Old woman with a book](图1)。这幅画曾在1898年阿姆斯特丹首次伦勃朗大展上展出,无怪乎弗里克(图2)想要将其收入囊... 详细信息

1916年,美国铁路大亨、艺术收藏家亨利·克莱·弗里克[Henry Clay Frick,1849-1919]买进伦勃朗的画作《持书的老妇》[Old woman with a book](图1)。这幅画曾在1898年阿姆斯特丹首次伦勃朗大展上展出,无怪乎弗里克(图2)想要将其收入囊中。他的博物馆现已成为一家公共博物馆,是纽约市最受珍视的财富之一。

关键词：伦勃朗公共博物馆阿姆斯特丹真迹收藏家纽约市

In silico assessment of household level closed water cycles:Towards extreme decentralization

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Environmental Science and Ecotechnology 2022年第2期10卷 1-11页

作者： Arjen van de walle Elena Torfs Dorien Gaublomme Korneel Rabaey Center for Microbial Ecology and Technology Ghent UniversityCoupure Links 6539000GhentBelgium Center for Advanced Process Technology for Urban Resource Recovery(CAPTURE) Coupure Links 6539000GhentBelgium BIOMATH Department of Data Analysis and Mathematical ModellingGhent UniversityCoupure links 6539000GhentBelgium

Water management in most of the developed world is currently practiced in a highly centralized manner,leading to major infrastructure and energy costs to transport *** decrease the impacts of water scarcity and climate change,the decentralization of water can increase local *** extremis,decentralization can involve building or house level water supply and ***,we constructed a MATLAB/Simulink model for two decentralized water management configurations at the household level,assuming the socio-environmental setting of Flanders,*** from the potable water grid and sewer system was pursued through rainwater harvesting,reuse of wastewater streams fitfor-purpose,and discharge via *** mass balance for water was calculated over the system boundaries showing high potential for independence from the grid with a reasonable treatment train and storage ***,the risk of contaminant accumulation within the circular system was assessed,showing a key limitation on decentralized system performance necessitating a system *** to 59%of system rainwater usage was due to the replacement of this *** treatment units with high(95%)contaminant rejection efficiencies eliminated contaminant accumulation *** raw model output was quantitatively assessed by constructing four newly proposed key performance indicators(KPIs),quantifying system independence,circularity,drought tolerance and local water body recharge,which allowed for facilitated system comparison and communication to stakeholders.A sensitivity analysis was performed in which the effect of input parameter variability and uncertainty on system performance was *** sensitivity analysis showed the importance of water recovery and contaminant removal efficiencies of the applied treatment technologies on system performance when contaminant accumulation in the system forms an *** systems not severely affected by pollutant accumulation,para

关键词： Extreme decentralization Household-scale Water reuse Simulations

Dispersal of invasive species by drifting

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Current Zoology 2011年第6期57卷 818-827页

作者： M.C. van RIEL G. van deR VELde A. BIJ de VAATE Radboud University Nijmegen Institute for Water and Wetland Research Department of Animal Ecology and Ecophysiology Section Aquatic Animal Ecology Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands Team Freshwater Ecology DLO-Alterra P.O. Box 47 6700 AA Wageningen The Netherlands Netherlands Centre for Biodiversity Naturalis EO. Box 9517 2300 RA Leiden The Netherlands Waterfauna Hydrobiologisch Adviesbureau Oostrandpark 30 8212 AP Lelystad The Netherlands

Drifting can be an effective way for aquatic organisms to disperse and colonise new areas. Increasing connectivity between European large rivers facilitates invasion by drifting aquatic macroinvertebrates. The present study shows that high abundances of invasive species drift in the headstream of the river Rhine. Dikerogammarus villosus and Chelicorophium cur- vispinum represented up to 90% of the total of drifting macroinvertebrates. Drift activity shows seasonal and diel patterns. Most species started drifting in spring and were most abundant in the water column during the summer period. Drift activity was very low during the winter period. Diel patterns were apparent; most species, including D. villosus, drifted during the night. Drifting macroinvertebrates colonised stony substrate directly from the water column. D. villosus generally colonised the substrate at night, while higher numbers of C. curvispinum colonised the substrate during the day. It is very likely that drifting functions as a disper- sal mechanism for crustacean invaders. Once waterways are connected, these species are no longer necessarily dependent on dispersal vectors other than drift for extending their distribution range

关键词： Amphipods Invaders Colonization Drift Daily rhythms Seasonal variation

Homing and migration of mesenchymal stromal cells: How to improve the efficacy of cell therapy?

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World Journal of Stem Cells 2016年第3期8卷 73-87页

作者： Ann de Becker Ivan van Riet department Clinical HematologyStem Cell Laboratory Universitair Ziekenhuis Brussel Vrije Universiteit Brussel (VUB)

Mesenchymal stromal cells(MSCs) are currently being investigated for use in a wide variety of clinical applications. For most of these applications, systemic delivery of the cells is preferred. However, this requires the homing and migration of MSCs to a target tissue. Although MSC hominghas been described, this process does not appear to be highly efficacious because only a few cells reach the target tissue and remain there after systemic administration. This has been ascribed to low expression levels of homing molecules, the loss of expression of such molecules during expansion, and the heterogeneity of MSCs in cultures and MSC culture protocols. To overcome these limitations, different methods to improve the homing capacity of MSCs have been examined. Here, we review the current understanding of MSC homing, with a particular focus on homing to bone marrow. In addition, we summarize the strategies that have been developed to improve this process. A better understanding of MSC biology, MSC migration and homing mechanisms will allow us to prepare MSCs with optimal homing capacities. The efficacy of therapeutic applications is dependent on efficient delivery of the cells and can, therefore, only benefit from better insights into the homing mechanisms.

关键词： Mesenchymal stromal cells Homing Bone marrow Homing receptors Extravasation

Is losing ethylene a losing game?

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Molecular Plant 2022年第5期15卷 788-790页

作者： Bram van de Poel Caren Chang Division of Crop Biotechnics Department of BiosystemsUniversity of LeuvenWillem de Croylaan 423001 LeuvenBelgium department of Cell Biology and Molecular Genetics University of MarylandCollege ParkMDUSA

It is well established that the gaseous plant hormone ethylene modulates growth and development and mediates re-sponses to biotic and abiotic *** plants produce ethylene from S-adenosyl-L-methionine,which is converted to 1-aminocyclopropane-1-carboxylic acid(ACC)by ACC synthase(ACS);ACC is then converted to ethylene by a dedicated enzyme,ACC oxidase(ACO)(Figure 1A).

关键词： Figure converted media

“Winter Is Coming” : How did Polyploid Plants Survive?

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Molecular Plant 2020年第1期13卷 4-5页

作者： Zhen Li Yves van de Peer department of Plant Biotechnology and Bioinformatics Ghent University9052 GhentBelgium VIB Center for Plant Systems Biology 9052 GhentBelgium Centre for Microbial Ecology and Genomics Department of BiochemistryGenetics and MicrobiologyUniversity of PretoriaPretoria 0028South Africa.

Cold and dark periods have descended on Earth several times in geological history. One such period characterized the Cretaceous-Paleogene (K-Pg) boundary, following a meteor impact near Chicxulub in Mexico, about 66 million years ago, which caused dust, sulfate aerosols, and soot particles to be ejected into the atmosphere. This in turn led to a so-called “impact winter,” inhibiting photosynthesis and causing a global collapse of terrestrial and marine food webs, leading to the extinction of 60%–70% of plants and animals ( Alvarez et al., 1980 ). Different from animals that might still be able to find shelter and detritus food in a harsh environment, plants are sessile and require (lots of) light for photosynthesis. How did they survive in a time of prolonged darkness and decreasing temperatures ( Vellekoop et al., 2016 )?

关键词： winter Cretaceous terrestrial

A Stochastic Model Approach for Optimisation of Lowland River Restoration Works

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Journal of Earth Science 2016年第1期27卷 55-67页

作者： Saskia van Vuren Huib de Vriend Hermjan Barneveld Section of Hydraulic Engineering Delft University of Technology 2600 AA Delft the Netherlands HKV Consultants Lelystad the Netherlands

Over the course of centuries, river systems have been heavily trained for the purpose of safe discharge of water, sediment and ice, and improves navigation. Traditionally, dikes are used to be reinforced and heightened to protect countries from ever higher flood levels. Other types of solutions than technical engineering solutions, such as measures to increase the flood conveyance capacity（e.g., lowering of groynes and floodplains, setting back dikes） become more popular. These solutions may however increase the river bed dynamics and thus impact negatively navigation, maintenance dredging and flood safety. A variety of numerical models are available to predict the impact of river restoration works on river processes. Often little attention is paid to the assessment of uncertainties. In this paper, we show how we can make uncertainty explicit using a stochastic approach. This approach helps identifying uncertainty sources and assessing their contribution to the overall uncertainty in river processes. The approach gives engineers a better understanding of system behaviour and enables them to intervene with the river system, so as to avoid undesired situations. We illustrate the merits of this stochastic approach for optimising lowland river restoration works in the Rhine in the Netherlands.

关键词： river restoration flood protection dredging navigation stochastic approach Room forthe River program.

Investigation of operational parameters for an industrial CFB combustor of coal,biomass and sludge

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China Particuology 2007年第4期5卷 247-254页

作者： Manon van de Velden Jan Baeyens Bill Dougan Alan McMurdo department of Chemical Engineering University of Birmingham B15 2TT Birmingham United Kingdom UPM-Kymmene Caledonian Paper Ltd.AyrUnited Kingdom

The combustion of coal and/or biomass （sludge, wood waste, RDF, etc.） in a circulating fluidized bed has been a commercial topper for over 20 years, and references to principles and applications are numerous and widespread although few data are presented concerning the operation of large scale CFB-units. The authors studied the CFB-combustion at UPM-Kymmene （Ayr）, a major paper mill relying for its steam production upon the combustion of coal （80-85 %）, wood bark （5-10%） and wastewater treatment sludge （5-10%）. The maximum capacity of the CFB is 58 MWth. A complete diagnostic of the operation was made, and additional tests were performed to assess the operating mode. The plant schematics, relevant dimensions and process data are given. To assess the operation of the UPM-CFB, it is important to review essential design parameters and principles of CFB combustors, which will be discussed in detail to include required data, heat balance and flowrates, operating versus transport velocity, kinetics and conversion （including the possible effect of the Bouduard reaction if carbon is present）. Since the residence time in the riser and the cyclone efficiency determine the burnout of circulating fuel-particles, the UPM-CFB was subjected to a stimulus response technique using nickel oxide as tracer. Results illustrate the efficiency of the cyclone separation and the number of recycle loops for particles of a given size. Results will also be used to assess the cyclone operation and efficiency and to comment upon expected and measured carbon conversion.

关键词： Circulating fluidized bed Combustion Coal Biomass Operation Cyclone