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SYNTHESIS OF SOLUBLE POLY(3,4-dIHYdROXY-o-TOLYLENE):REdOX POLYmER

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Chinese Journal of Polymer Science 2006年第1期24卷 41-46页

作者： sad moulay Fatima m'zyène Laboratoire de Chimie-Physique moléculaire et macromoléculaire Faculté des Sciences de l'Ingénieur département de Chimie Industrielle Université de BlidaRoute de SoumèaB.P.270Blida 09000Algeria. Laboratoire de Chimie-Physique moléculaire et macromoléculaire Faculté des Sciences de l'Ingénieur département de Chimie Industrielle Université de BlidaRoute de SoumaB.P.270Blida 09000Algeria.

Conventional chloromethylation, paraformaldehyde/hydrogen chloride in acetic acid medium, was applied to 1,2- dimethoxybenzene. Chloroform-soluble poly（3,4-dimethoxy-o-tolylene） was obtained with an intrinsic viscosity of 0.034 dL g^-1. The polymer was evaluated as a condensation redox polymer precursor formed by a Friedel-Crafts reaction. Cleavage of the methoxy groups present in this polymer resulted in poly（3,4-dihydroxy-o-tolylene） which manifested a great air-oxidation resistance. The redox property of the latter polymer was found to be 1017 mV by potentiometric titration with 0.05 N ceric ammonium nitrate at 25℃. This midpotential was compared to that of catechol, a monomeric analogue, under the same titration conditions.

关键词： Poly(3,4-dimethoxy-o-tolylene) Poly(3,4-dihydroxy-o-tolylene) Redox polymer.

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Effects of human disturbance on nest placement of the woodpigeon (Columba palumbus): a case study from the middle Atlas, morocco

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Integrative Zoology 2014年第3期9卷 349-359页

作者： saâd HANANE Forest Research Center High Commissariat for WaterForests and Desertification ControlRabat-AgdalMorocco

The woodpigeon(Columba palumbus)is a common and widespread bird in morocco(North Africa).I examined,over 2 years(2010 and 2011),the breeding density and nest placement of this game species in relation to nest site habitat and degree of human *** study area was in the middle Atlas Tighboula mountain forest,morocco,in a disturbed and an undisturbed *** data collected in the 2 study sites,I aimed to identify the factors influencing the placement of nests within holm oak trees(Quercus rotundifolia)and their densities.I found that habitat structures,influenced by grazing disturbance,have affected nesting density and the location of nests of this *** place their nests in a higher position(3.42±0.19 m)when disturbance intensity is high and lower(1.68±0.1 m)when disturbance intensity is low,and show higher nesting density in less disturbed zone(3.1±0.4 nests/ha)than in highly disturbed zones(1.4±0.2 nests/ha).Grazing disturbance could pose a threat to population persistence at a broader scale and could potentially reduce the abundance of this species by altering the composition and the structure of the forest nesting *** multi-scale studies are needed to assess the effects of different levels of grazing disturbance on woodpigeon nest density and placement,and to enhance our knowledge of the breeding behavior of this game species under variable environments.

关键词： breeding density Columba palumbus holm oak middle Atlas morocco nest location woodpigeon

Seasonal variability in CdOm absorption and fluorescence properties in the Barataria Basin,Louisiana,Usa

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Journal of Environmental Sciences 2010年第10期22卷 1481-1490页

作者： Shatrughan Singh Eurico d'sa Erick Swenson department of Oceanography and Coastal Sciences Louisiana State University

Absorption and fluorescence properties of chromophoric dissolved organic matter （CdOm） along a 124 km transect in the Barataria Basin, a large estuary located in Louisiana, Usa, were investigated during high and low flow periods of the mississippi River in the spring and winter of 2008-2009. mean CdOm absorption at 355 nm from the marine to the freshwater end member stations ranged from （3.25 ± 0.56） to （20.76 ± 2.43） m^-1 for the three month high flow period whereas it varied from （1.48 ± 1.08） to （25.45 ± 7.03） m^-1 for the same stations during low flow period. Corresponding salinity values at these stations indicated the influence of river and shelf exchanges in the lower basin and precipitation and runoff in the upper basin. An inverse relationship of CdOm absorbance and fluorescence with salinity observed in the basin could he a useful indicator of salinity. CdOm fluorescence also varied over a large range showing an approximately 8 to 12-fold increase between the marine and freshwater end members for the two flow seasons. Excitation-emission matrix spectral plots indicated the presence of various fluorescence components with highest being the A-peak, lowest the T-peak, and the C and m-peaks showing similar trends along the transect. during low flow season the A/C ratio were well correlated with station locations indicating increased terrestrial influence towards the upper basin. CdOm absorption and fluorescence at 355 nm were highly correlated and independent of CdOm sources suggesting that fluorescence could be used to characterize CdOm in the basin.

关键词： Barataria Basin chromophoric dissolved organic matter CdOm fluorescence excitation-emission matrix

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Analysis and optimal synthesis of single loop spatial mechanisms

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第9期12卷 665-679页

作者： med Amine LARIBI Lotfi ROmdHANE sad ZEGHLOUL Laboratoire de Génie mécanique LAB-MA-05 Ecole Nationale d'Ingénieurs de Sousse Institut Pprime-UPR 3346 CNRS-Université de Poitiers-ENSMA Département Génie Mécanique et Systémes Complexes SP2MIBP30179 86962 Futuroscope France

In this work, a systematic approach is presented to obtain the input-output equations of a single loop 4-bar spatial mechanisms. The dialytic method along with denavit-Hartenberg parameters can be used to obtain these equations efficiently. A genetic algorithm （GA） has been used to solve the problem of spatial mechanisms synthesis. Two types of mechanisms, e.g., RSCR and RSPC （R： revolute; S： spherical; C： cylindrical; P： prismatic）, have illustrated the application of the GA to solve the problem of function generation and path generation. In some cases, the GA method becomes trapped in a local minimum. A combined GA-fuzzy logic （GA-FL） method is then used to improve the final result. The results show that GAs, combined with an adequate description of the mechanism, are well suited for spatial mechanism synthesis problems and have neither difficulties inherent to the choice of the initial feasible guess, nor a problem of convergence, as it is the case for deterministic methods.

关键词： Spatial mechanisms Genetic algorithm-fuzzy logic (GA-FL) method denevit-Hartenberg parameters mechanism synthesis

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Ion emission from warm dense matter produced by irradiation with a soft x-ray free-electron laser

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matter and Radiation at Extremes 2024年第1期9卷 71-84页

作者： Josef Krása Tomás Burian Vera Hájková Jaromír Chalupský Šimon Jelínek Katerina Frantálová michal Krupka Zuzana Kuglerová Sushil Kumar Singh Vojtech Vozda Ludek Vysín michalŠmíd Pablo Perez-martin marion Kühlman Juan Pintor Jakub Cikhardt matthias dreimann dennis Eckermann Felix Rosenthal sam m.Vinko Alessandro Forte Thomas Gawne Thomas Campbell Shenyuan Ren YuanFeng Shi Trevor Hutchinson Oliver Humphries Thomas Preston mikako makita motoaki Nakatsutsumi Xiayun Pan Alexander Köhler marion Harmand Sven Toleikis Katerina Falk Libor Juha department of Radiation and Chemical Physics Institute of PhysicsCzech Academy of SciencesNa Slovance 218221 Prague 8Czech Republic Laser Plasma department Institute of Plasma PhysicsCzech Academy of SciencesZa Slovankou 318200 Prague 8Czech Republic department of Surface and Plasma Science Faculty of Mathematics and PhysicsCharles University in PragueV Holesovi ckách 218000 Prague 8Czech Republic department of Physical Electronics Faculty of Nuclear Science and Engineering PhysicsCzech Technical University in PragueV Holesovi ckách 218000 Prague 8Czech Republic Helmholtz-Zentrum dresden-Rossendorf Bautzner Landstraße 40001328 DresdenGermany dESY Photon Science Notkestraße 85D-22607 HamburgGermany Institut de minéralogie de Physique des Matériaux et de CosmochimieUMR 7590–UPMC/CNRS/IRD/MNHNSorbonne Université4 place Jussieu75005 ParisFrance department of Physics Faculty of Electrical EngineeringCzech Technical University in PragueTechnická216627 Prague 6Czech Republic Center for Soft Nanoscience University of MünsterBusso-Peus-Straße 10D-48149 MünsterGermany department of Physics Clarendon LaboratoryUniversity of OxfordParks RoadOxford OX13PUUnited Kingdom Central Laser Facility STFC Rutherford Appleton LaboratoryDidcot OX110QXUnited Kingdom Lawrence Livermore National Laboratory 7000 East AvenueLivermoreCalifornia 94550USA European XFEL GmbH Holzkoppel 4D-22869 SchenefeldGermany Technische Universität dresden 01062 DresdenGermany

We report on an experiment performed at the FLASH2 free-electron laser(FEL)aimed at producing warm dense matter via soft x-ray isochoric *** the experiment,we focus on study of the ions emitted during the soft x-ray ablation process using time-of-flight electron multipliers and a shifted maxwell–Boltzmann velocity distribution *** find that most emitted ions are thermal,but that some impurities chemisorbed on the target surface,such as protons,are accelerated by the electrostatic field created in the plasma by escaped *** morphology of the complex crater structure indicates the presence of several ion groups with varying *** find that the ion sound velocity is controlled by the ion temperature and show how the ion yield depends on the FEL radiation attenuation length in different materials.

关键词： electrostatic emitted chemi

Hepatocellular carcinoma-the role of the underlying liver disease in clinical practice

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World Journal of Gastroenterology 2024年第19期30卷 2488-2495页

作者： Angelo Zambam de mattos Isadora Zanotelli Bombassaro Arndt Vogel Jose d debes department of Internal medicine Universidade Federal de Ciências da Saúde de Porto AlegreRSPorto Alegre 90020090Brazil Graduate Program in medicine:Hepatology Federal University of Health Sciences of Porto AlegreRSPorto Alegre 90050-170Brazil division of Gastroenterology Hepatology University of TorontoHannover M5R 0A3Canada department of medicine University of MinnesotaMinneapolisMN 55455United States

Hepatocellular carcinoma(HCC)is one of the most common causes of cancerrelated *** particular type of cancer has the distinctive characteristic of mostly happening in individuals with an underlying liver *** makes the management of patients more challenging,since physicians must take into consideration two different conditions,the chronic liver disease and the *** underlying liver disease has several implications in clinical practice,because different kinds of chronic liver disease can lead to varying degrees of risk of developing HCC,obstacles in surveillance,and differences in the efficacy of the treatment against HCC.A shift in the prevalence of liver diseases has been evident over the last few years,with viral hepatitis gradually losing the leading position as cause of HCC and metabolic dysfunction-associated steatotic liver disease gaining ***,in an era of personalized medicine,it is imperative that physicians are aware of the underlying liver disease of individuals with HCC and its impact in the management of their tumors.

关键词： Hepatocellular carcinoma Etiology Epidemiology Surveillance Therapy

The gold-telluride connection:Evidence for multiple fluid pulses in the Jinqingding telluride-rich gold deposit of Jiaodong Peninsula,Eastern China

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Geoscience Frontiers 2024年第3期15卷 146-165页

作者： Wenyan Cai mingchun Song m.santosh Jian Li School of Resources and Environmental Engineering Shandong University of TechnologyZibo 255049China Hebei Key Laboratory of Strategic Critical mineral Resources Hebei GEO UniversityShijiazhuang 050031China School of Earth Sciences and Resources China University of Geosciences Beijing29 Xueyuan RoadBeijing 100083China department of Earth Science University of AdelaideAdelaide SA 5005Australia

The mechanism of gold migration,enrichment,and precipitation in forming world-class gold deposits has been a topic of wide interest,particularly where these deposits are abundant in *** Jiaodong Peninsula in eastern China hosts some of the world-class gold deposits among which the Jinqingding deposit is one of the best examples with substantial telluride mineralization and thus provides opportunity to investigate the genetic connection between tellurium and gold *** orebody in this deposit is hosted in the NE-NNE-trending Jiangjunshi-Quhezhuang fault with the Jurassic Kunyushan granitic pluton as wall *** deposit involved three mineralization stages as inferred from assemblages and crosscutting relationships between *** stages are:(I)pre-ore gold-poor quartz-pyrite veins,(II)main ore auriferous quartz-pyrite-Te/Bi-minerals±sphalerite±chalcopyrite±barite±marcasite veins,and(III)post-ore quartz-calcite *** present here the textural,isotopic,and geochemical variations of different stages/generations of pyrite based on scanning electron microscopy-energy dispersive spectroscopy(SEm-EdS),electron probe microanalysis(EPmA),and laser ablation inductively coupled plasma mass spectrometry(LA-ICP-mS).Pyrite in the Jinqingding deposit displays distinct ***1a shows a porous and dissolution-reprecipitation texture in the core,whereas Py1b exhibits a smooth and flat *** analysis reveals contrasting elemental compositions,with Py1a characterized by low Au(avg.0.14 ppm),As(avg.15.57 ppm),Ag(avg.17.71 ppm),and Te(avg.19.22 ppm)contents,but elevated Co(avg.1068.10 ppm)and Ni(224.12 ppm)concentrations,and variable sulfur isotopic composition(δ^(34)SV-CdT=9.54‰-12.12‰).Conversely,Py1b displays increased concentrations of these elements and a more concentratedδ^(34)SV-CdT value(11.99‰-12.23‰),possibly associated with weak coupled dissolution-reprecipitation(CdR)*** Stage II,pyrite can be further categorized

关键词： Episodic fluid pulses Sulfur reservoir Gold-Te precipitation Jinqingding deposit Jiaodong Peninsula

Fluid dynamics analysis and pyrolysis of brewer’s spent grain in a spouted bed reactor

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Particuology 2019年第1期17卷 199-207页

作者： marcos A.S. Barrozo Lidja d.m.S. Borel Taísa S. Lira Carlos H. Ataíde School of Chemical Engineering Federal University of UberlandiaBrazil department of Engineering and Technologies Federal University of Espirito SantoBrazil

Brewer’s spent grain (BSG) is a large-scale agroindustrial waste that could be more efficiently utilized. This waste is composed of lignocellulosic material and so may serve as a good source of biomass for thermochemical conversion. The present study investigated the fluid dynamics behavior of mixtures of sand and BSG in a spouted bed to assess the viability of the thermochemical conversion of this biomass via fast pyrolysis. Fluid dynamics analyses were performed while varying the mass fraction of BSG (6–80%) and the static bed height (6.6–13.4 cm). Empirical equations for predicting the minimum spouting conditions and the mixing index were obtained using a regression technique, and the selected fluid dynamics parameters were employed in the spouted bed pyrolysis. The bio-oil resulting from this process was rich in phenolic compounds, various nitrogenated compounds (representing precursors for pharmaceuticals) and long-chain hydrocarbons. The products obtained from the analytical and spouted bed pyrolysis processes were also compared.

关键词： Brewer’s spent grain Agroindustrial residue Spouted bed Fast pyrolysis Particle mixing

Halophily reloaded:new insights into the extremophilic life-style of Wallemia with the description of Wallemia hederae ***

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Fungal diversity 2016年第1期76卷 97-118页

作者： sašo Jančič Polona Zalar dragi Kocev Hans-Josef Schroers sašo džeroski Nina Gunde-Cimerman department of Biology Biotechnical FacultyJamnikarjeva 101SI-1000 LjubljanaSlovenia department of Knowledge Technologies Jožef Stefan InstituteJamova cesta 39SI-1000 LjubljanaSlovenia Agricultural Institute of Slovenia Hacquetova 17p.p.2553SI-1000 LjubljanaSlovenia Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins(CIPKeBiP) Jamova cesta 39SI-1000 LjubljanaSlovenia

Wallemia comprises air-and food-borne,mycotoxigenic contaminants including the halophilic ***,xerotolerant *** and xerophilic *** isolates are easily overlooked and only a comparably small number of strains have been deposited in culture collections so *** order to better understand the natural distribution of Wallemia *** to encounter their natural habitats,we tested more than 300 low-water-activity substrates and 30 air samples from a wide geographical *** isolated more than 150 new Wallemia *** sebi and *** were isolated mostly from hypersaline water,low-water-activity foods,plant materials and *** muriae is the dominant Wallemia species in the air of natural and human influenced environments in *** isolates of *** were obtained from hypersaline environments such as brine,salt crystals,salty foods and mgCl_(2)-rich bitterns,and from the air of hay barns in *** halotolerant strains were recognised as a hitherto un-described species Wallemia hederae,the phylogenetic sister of the halophilic *** *** in-vitro growth on media that contain the chaotropic salt mgCl_(2).Wallemia ichthyophaga can grow in liquid medium enriched with 2 m mgCl_(2).Never before has a microorganism been grown on comparably high mgCl_(2) *** of the activity of a wide range of extracellular enzymes in the presence of NaCl also suggested that Wallemia iswell-adapted to substrates with a reduced water activity.

关键词： Chaophiles Ecophysiology Extracellular enzymes Exudates machine learning Taxonomy