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Touristic urbanization and greening of coastal dune fields:A long-term assessment of a temperate sandy barrier of Argentina

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j.urnal of Geographical Sciences 2025年第1期 206-230页

作者： GARZO Pedro andrés DADON j.sé Roberto ISLA Federico Ignacio Instituto de Investigaciones Marinas y Costeras (IIMyC-CONICET/UNMDP) Instituto de Geología de Costas y del Cuaternario Dr.Enrique j.Schnack (IGCC-CIC/UNMDP) Universidad de Buenos Aires Facultad de Arquitectura Dise?o y Urbanismo Centro de Investigaciones Gestión de Espacios Costeros (GEC-FADU/UBA) Consej. Nacional de Investigaciones Científicas y Técnicas (CONICET)

Dune barrier systems represent highly sought-after coastal landscapes for tourism and urban development around the world. However, a century ago, they were considered hazardous environments due to their great dynamic nature. As a result, stabilization practices were considered necessary. The systematic introduction of fast-growing exotic trees helped stabilize the sand, making it easier for tourism urbanization to take place, but also leading to erosion processes. This paper aims to assess long-term changes in vegetation cover over a large temperate barrier in Argentina. This complex region includes urban resorts, afforestation zones, and protected areas. A GIS-based geospatial analysis was conducted using a large satellite database(> 350 images), and the future evolution of the vegetation was modeled. The results revealed two primary spatiotemporal patterns associated with a gradual expansion of vegetation cover, accompanied by a concurrent reduction in sandy areas. In 1986, the dune area comprised 75% more surface than vegetation, whereas in 2021, it represented 60% less than vegetation. Furthermore, the 2050 scenario suggests a potential 40% reduction of dunes in certain areas. It is necessary to enhance management actions aimed at maintaining dune mobility and ensuring local and regional sediment balance. Long-term management strategies must focus on restoring native plant communities and controlling invasive species, and avoiding new dune fixation initiatives based on the introduction of exotic species.

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Reactive Extraction of Alcohols from Apolar Hydrocarbons with Aqueous Solutions

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Tsinghua Science and Technology 2006年第2期11卷 222-227页

作者： Boris Kuzmanovi Norbert j. M. Kuipers andré B. de Haan Gerard Kwant Akzo Nobel Chemicals Research Arnhem The Netherlands University of Twente Enschede The Netherlands DSM Research Geleen The Netherlands

The aqueous solutions are evaluated as sustainable reactive extraction solvents for the recovery of monohydroxyl alcohols （benzyl alcohol, 1-hexanol, cyclohexanol） present in few-percent concentrations in apolar hydrocarbons （toluene, n-hexane, and cyclohexane） by considering two approaches. An aqueous solution containing a reactive extractant, like borate salts, borate complexes, a monosalt of dicarboxylic acid, hydroxypropyl-cyclodextrins, and silver nitrate, shows limited potential to be used. Another approach, in which the alcohol is chemically modified prior to the extraction into an easy-extractable form, in this case a monoester/carboxylic acid, shows much more potential. An environmentally benign aqueous solution of sodium hydrogen carbonate can provide a distribution ratio of benzyl alcohol up to 200, leaving the solubility of the organic solvent in the aqueous solution unchanged relative to pure water and therefore increasing the selectivity with two orders of magnitude. The modification of aromatic, cyclo-aliphatic, and linear aliphatic alcohols can be performed efficiently in the apolar organic solvent without need for a catalyst. The recovery of the modified alcohol can be performed by back-extraction in combination with a spontaneous hydrolysis.

关键词： reactive extraction alcohol polar hydrocarbons

Surface movement above old coal longwalls after mine closure

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International j.urnal of Mining Science and Technology 2017年第3期27卷 481-490页

作者： andré Vervoort Pierre-Yves Declercq Department of Civil Engineering KU Leuven Leuven 3001 Belgium Geological Survey of Belgium Royal Belgian Institute of Natural Sciences Brussels 1000 Belgium

Although most subsidence occurs in the months and years after mining by the longwall method, surface movement is still occurring many decades after the mining. The aim of the study is to quantify the long term behavior. Satellite data(radar-interferometry) were analyzed to study an area of about 2 km^2 during the 18 years following the closure of the underground infrastructure and the flooding of the underground workings and rock mass. It was observed that, on average, a residual downward movement took place till 7–12 years after the closure, followed by a clear uplift. However, the first signs of an uplift occurred in certain sub-areas 3–4 years after the closure. Zones within the area studied were identified with either larger or smaller movements. However, the spatial variation of the surface subsidence or uplift could not be directly explained by the characteristics of mining.

关键词： Coal mining Surface movement Subsidence Uplift Radar-interferometry

Electrocardiographic and echocardiographic dyssynchrony parameters that might better predict the response to cardiac resynchronization therapy than QRS morphology and duration

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j.urnal of Geriatric Cardiology 2022年第2期19卷 98-100页

作者： andrás Vereckei Department of Medicine and Hematology Semmelweis UniversityBudapestHungary

Cardiac resynchronization therapy(CRT)is an evidence-based effective therapy of symptomatic heart failure with reduced ej.ction fraction refractory to optimal medical ther-apy and associated with intraventricular conduction disturbance,that results in a significant electrical ventricular ***,the non-response rate to CRT is still 20%−40%.[1]The potential underlying causes of CRT nonresponse are:(1)suboptimal localization of the left ventricular(LV)electrode,far away from the latest activated LV region.

关键词： ventricular synchronization echocardiographic

Upward surface movement above deep coal mines after closure and flooding of underground workings

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International j.urnal of Mining Science and Technology 2018年第1期28卷 53-59页

作者： andré Vervoort Pierre-Yves Declercq Department of Civil Engineering KU Leuven Geological Survey of Belgium Royal Belgian Institute of Natural Sciences

After the mass closures of entire coal mine districts in Europe at the end of the last century, a new phenomenon of surface movement was observed—an upward *** most surface movement(i.e., subsidence) occurs in the months and years after mining by the longwall method, surface movement still occurs many decades after mining is *** the closure and flooding of underground excavations and surrounding rock, this movement was *** paper focuses on quantifying the upward movement in two neighboring coal mines(winterslag and Zwartberg, Belgium).The study is based on data from a remote sensing technique: interferometry with synthetic aperture radar(INSAR).The results of the study show that the rate of upward movement in the decade after closure is about 10 mm/year on *** upward movements are not linked directly to the past exploitation directly underneath a *** amounts of subsidence at specific locations are linked mainly to their positions relative to an inverse trough shape situated over the entire mined-out areas and their immediate *** features, such as geological faults, can have a secondary effect on the local variation of the *** processes of subsidence and uplift are based on completely different *** is initiated by a caving process, while the process of uplift is clearly linked to flooding.

关键词： Coal mining Surface movement Subsidence Uplift Radar-interferometry

Survey of recent advances of in the field of π-conj.gated heterocyclic azomethines as materials with tuneable properties

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Science China Chemistry 2013年第1期56卷 3-23页

作者： BOLDUC andréanne MALLET Charlotte SKENE w. G. Laboratoire de Caractérisation Photophysique des Matériaux Conj.gués Département de ChimieUniversité de MontréalCP 6128Centre-villeMontrealQC H3C 3J7Canada

This account gives an overview of our recent work in the area of conj.gated azomethines derived from *** will be presented that mild reaction conditions can be used to selectively prepare symmetric and unsymmetric conj.gated *** further will be demonstrated that azomethines consisting of various 5-membered aryl heterocycles lead to chemically,reductively,hydrolytically,and oxidatively robust *** optical and electrochemical properties of these materials can be tuned contingent on the degree of conj.gation,type of aryl heterocycle,and by including various electronic *** end result is materials having colors spanning 250 nm across the visible *** colors further can be tuned via electrochemical or chemical *** resulting doped states have high color contrasts from their corresponding neutral *** collective opto-electronic properties and the means to readily tune them,make thiophenoazomethine derivatives interesting materials for potential use in a gamut of applications.

关键词： review azomethines electronic push-pull electrochromism polymers thiophene conj.gated materials X-ray crystallography

Deductive way of reasoning about the internet AS level topology

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Chinese Physics B 2015年第11期24卷 633-642页

作者： Dávid Szabó Attila Korsi j.zsef Bíró andrás Gulyás High Speed Networks Laboratory Budapest University of Technology and Economics MTA-BME Information Systems Research Group Budapest University of Technology and Economics MTA-BME Future Internet Research Group Budapest University of Technology and Economics

Our current understanding about the AS level topology of the Internet is based on measurements and inductive-type models which set up rules describing the behavior （node and edge dynamics） of the individual ASes and generalize the consequences of these individual actions for the complete AS ecosystem using induction. In this paper we suggest a third, deductive approach in which we have premises for the whole AS system and the consequences of these premises are determined through deductive reasoning. we show that such a deductive approach can give complementary insights into the topological properties of the AS graph. while inductive models can mostly reflect high level statistics （e.g., degree distribution, clustering, diameter）, deductive reasoning can identify omnipresent subgraphs and peering likelihood. we also propose a model, called YEAS, incorporating our deductive analytical findings that produces topologies contain both traditional and novel metrics for the AS level Internet.

关键词： internet topology complex network analysis model

RESEARCH ON MEASURING METHOD OF THE THERMALCONDUCTIVITY FOR HIGHLY POROUS MATERIALS

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Acta Metallurgica Sinica(English Letters) 1997年第3期10卷 213-218页

作者： j.Y wu Z.M. Tang w Shi andr.Z. wang (Institute of Refrigeration and Cryogenics Engineering, Shanghai j.ao Tong University, Shanghai 200030,China) Shanghai j.aotong Univ Shanghai China

A transient method with rectangular pulse heating has been developed to measure the thermal conductivity of highly porous materials such as activated carbon, zeolite and silica gel. By this method the thermal conductivity can be measured quickly and accu-rately. In this paper, a set of automatically controlled testing equiptnent is *** measuring method is analysed. The thermal conductivities of some samples, such as activated carbon and zeolite, are measured by the equipment. A group of useful data has been obtained.

关键词： thermal conductivity porous material thermophysical property

Parallel droplet microfluidics for high throughput cell encapsulation and synthetic microgel generation

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Microsystems & Nanoengineering 2018年第1期4卷 525-533页

作者： Devon M.Headen j.séR.García andrés j.García woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA Petit Institute for Bioengineering and Biosciences Georgia Institute of TechnologyAtlantaGA 30332USA

Cells can be microencapsulated in synthetic hydrogel microspheres(microgels)using droplet microfluidics,but microfluidic devices with a single droplet generating geometry have limited throughput,especially as microgel diameter *** we demonstrate microencapsulation of human mesenchymal stem cells(hMSCs)in small(o100μm diameter)microgels utilizing parallel droplet generators on a two-layer elastomer device,which has 600% increased throughput ***-nozzle *** of microgel diameters were compared between products of parallel ***-nozzle configurations for two square nozzle widths,35 and 100μ*** produced on parallel nozzles were equivalent to those produced on single nozzles,with substantially the same *** of hMSCs was compared for parallel nozzle devices of each *** five micrometer wide nozzle devices could be operated at twice the cell concentration of 100μm wide nozzle devices but produced more empty microgels than predicted by a Poisson *** micrometer wide nozzle devices produced microgels as predicted by a Poisson *** of microgels did not increase with the addition of cells for either nozzle *** encapsulated on 35μm wide nozzle devices had reduced viability(~70%)and a corresponding decrease in vascular endothelial growth factor(VEGF)secretion compared to hMSCs cultured on tissue culture(TC)*** hMSCs using 100μm wide nozzle devices mitigated loss of viability and function,as measured by VEGF secretion.

关键词： droplets microencapsulation microgel multilayer parallel