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Chinese Chemical Letters 2024年第2期35卷 558-563页

作者： Sheng Cai Xiao-Yuan Wu Weiming Wu sa-sa Wang Can-Zhong Lu CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350117China Xiamen Institute of Rare Earth Materials Chinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Partial substitution of polyoxometalate(POM)is an efficient route to modulate the catalytic property of maternal *** this work,a new Keggin type POM involving{Ni 6}cluster,{[Ni(H_(2)O)_(2)(Dach)_(2)][Ni(Dach)_(2)]_(2)}{[Ni_(6)Cl(μ-OH)_(3)(H_(2)O)(Dach)_(3)(WO_(4))(PW9 O_(3)_(4))][Ni_(6)(μ-OH)_(3)(H_(2)O)_(2)(Dach)_(3)(WO_(4))(PW9 O_(3)_(4))]}Cl·27H_(2)O,(1,Dach=1,2-diaminocyclohexane)was *** 1 shows excellent catalytic performance in the selective oxidation of aniline to azoxybenzene(AOB)in *** apparently different results from that with the matrix{PW_(9)O_(34)}({PW9})suggest the successful regulation of the catalytic property of{PW9}by the introduction of the{Ni6}cluster into the *** experimental results indicate that the highlighted performance of 1 is contributed by the synergy of W and Ni sites,which are respectively responsible for the oxidation and condensation steps in the production of *** good selectivity to AOB is essentially attributed to the effective modulation of the reaction rates of oxidation and condensation steps by W and Ni sites,respectively.

关键词： Polyoxometalate {Ni_(6)}cluster Modulated catalytic property Aniline oxidation Azoxybenzene

Carbon accumulations by stock change approach in tropical highland forests of Chiapas, Mexico

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Journal of Forestry Research 2020年第6期31卷 2479-2493页

作者： Deb R.Aryal Roldan ruiz-Corzo CONACYT-UNACH Facultad de Ciencias Agrono´micasUniversidad Auto´noma de ChiapasCarretera Ocozocoautla-Villaflores km 84.530470 VillafloresCHISMexico Facultad de Ciencias Agrono´micas Universidad Auto´noma de ChiapasCarretera Ocozocoautla-Villaflores km 84.530470 VillafloresCHISMexico

Changes in forest biomass and soil organic carbon reserves have strong links to atmospheric carbon dioxide *** activities such as livestock grazing,forest fires,selective logging and firewood extraction are the common disturbances that affect the carbon dynamics of the forest ***,we hypothesized that such anthropogenic activities significantly reduce the carbon stocks and accumulation rates in the tropical highland forests of the Sierra Madre de Chiapas in Southern *** sampled the Pinus oocarpa Scheide dominated forests within the elevation range of 900 to 1100 m above sea level in 2010,2014 and *** measured the stand structural properties and used the reported allometric equations to calculate the tree carbon *** change approach was used to calculate carbon accumulation *** results showed a gradual increase in carbon storage over the 7-year period from 2010 to 2017,but the rate of increase varied significantly between the study *** aboveground carbon stock was 107.25±11.77 Mg ha-1 for the site with lower anthropogenic intensity,compared to 74.29±16.85 Mg ha-1 for the site with higher *** current annual increment for the forest with lower anthropogenic intensity was 7.81±0.65 Mg ha-1 a-1,compared to 3.87±1.03 Mg ha-1 a-1 in the site with high anthropogenic *** at varying rates,these forests are functioning as important carbon *** results on carbon accumulation rates have important implications in greenhouse gas mitigations and forest change modelling in the context of changing global climate.

关键词： Anthropogenic disturbances Biomass Carbon accumulation rates Forest carbon pools Forest structure Southern Mexico

ON NEW STRATEGIES TO CONTROL THE ACCURACY OF WENO ALGORITHM CLOSE TO DISCONTINUITIES Ⅱ:CELL AVERAGES AND MULTIRESOLUTION

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Journal of Computational Mathematics 2020年第4期38卷 661-682页

作者： Sergio Amat Juan ruiz Chi-Wang Shu Department of Applied Mathematics and Statistics Universidad Politecnica de CartagenaSpain Division of Applied Mathematics Brown UniversityUSA

This paper is the second part of the article and is devoted to the construction and analysis of new non-linear optimal weights for WENO interpolation capable of rising the order of accuracy close to discontinuities for data discretized in the cell ***,now we are interested in analyze the capabilities of the new algorithm when working with functions belonging to the subspace L1\L2 and that,consequently,are piecewise smooth and can present jump *** new non-linear optimal weights are redesigned in a way that leads to optimal theoretical accuracy close to the discontinuities and at smooth *** will present the new algorithm for the approximation case and we will analyze its *** we will explain how to use the new algorithm in multiresolution applications for univariate and bivariate *** numerical results confirm the theoretical proofs presented.

关键词： WENO Cell averages New optimal weights Multiresolution schemes Im-proved adaption to discontinuities Signal processing

salinity Distribution at Canal Istanbul and Its Possible Impacts on the Northern Marmara Sea

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China Ocean Engineering 2020年第6期34卷 881-888页

作者： Şehriban saÇU Tarkan ERDIK OlgayŞEN Istanbul Technical University MaslakIstanbul 34467Turkey

Turkey has announced its plan to construct a new waterway, Canal Istanbul, parallel to the Bosphorus. In this study,the influence of Canal Istanbul on salinity distribution in the northern Marmara Sea is investigated using a previously calibrated 3 D hydrodynamic and salinity model. Moreover, the salinity field of the canal and its propagation are examined based on various meteorological cases. Finally, the flow structure of the canal is determined. It is calculated that at the southern end of the canal, mainly unidirectional flow(from the Black Sea to the Marmara Sea)occurs during 68% of the simulation period. A two-layer flow is seen only 28% of the time with a weak lower layer flow, whereas this value decreases to 4% at the north end of the canal. In the southward direction(to the Marmara Sea), velocities higher than 1.5 m/s are rarely observed along the canal. The average surface salinity difference in the northern Marmara Sea due to the construction of the canal is calculated to be smaller than 0.50 ppt. The salinity difference gradually diminishes as water depth increases and after 25 m(from the surface) almost no difference is observed.

关键词： Canal Istanbul Marmara Sea salinity distribution hydrodynamic modeling

Thermal comfort in twentieth-century architectural heritase： Two houses of Le Corbusier and Andre Wogenscky

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Frontiers of Architectural Research 2016年第2期5卷 157-170页

作者： Ignacio Requena-ruiz AAU-CRENAU UMR CNRS 1563 Graduate School of Architecture of Nantes Nantes 44262 France

The study of the relationship of climate and indoor thermal environments in architecture is essential to understand the inhabitants＇ sensory perception. This is even more relevant when working in the existing housing stock in view of the new challenges posed by the conservation of the 20th century architectural heritage and the adaption of these buildings to our current comfort and environmental criteria. This article aims to develop a balanced understanding of the approach of Modernist architecture to climate, indoor atmospheres and inhabitants＇ thermal comfort. To do so, we complement the quantitative approach of environmental assessment methods with the qualitative angle of the history of sensory and architecture. The goal is to understand the environmental performance of architecture for dealing nowadays with thermal comfort issues while respecting its cultural and historical values. Two modernist houses have been selected as case studies： the Villa Curutchet of the master Le Corbusier and the Villa Chupin of his discipte Andr Wogenscky. As a result, the article reveals potentialities and constraints in terms of thermal comfort when working with Modern Architecture.

关键词： Thermal comfort Twentieth-centuryheritage Thermal simutation Thermal atmo-spheres Le Corbusier Wogenscky

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.

Particle Swarm Optimization Based Support Vector Regression for Blind Image Restoration

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Journal of Computer Science & Technology 2012年第5期27卷 989-995页

作者： Ratnakar Dash Pankaj Kumar sa Banshidhar Majhi Computer Science and Engineering Department National Institute of Technology RourkelaRourkela 769008India

This paper presents a swarm intelligence based parameter optimization of the support vector machine （SVM） for blind image restoration. In this work, SVM is used to solve a regression problem. Support vector regression （SVR） has been utilized to obtain a true mapping of images from the observed noisy blurred images. The parameters of SVR are optimized through particle swarm optimization （PSO） technique. The restoration error function has been utilized as the fitness function for PSO. The suggested scheme tries to adapt the SVM parameters depending on the type of blur and noise strength and the experimental results validate its effectiveness. The results show that the parameter optimization of the SVR model gives better performance than conventional SVR model as well as other competent schemes for blind image restoration.

关键词： image restoration support vector regression particle swarm optimization

Global research on Clostridium difficile-associated diarrhoea:A visualized study

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World Journal of Gastroenterology 2022年第28期28卷 3720-3731页

作者： sa'ed H Zyoud Department of Clinical and Community Pharmacy College of Medicine and Health SciencesAn-Najah National UniversityNablus 44839Palestine Poison Control and Drug Information Center College of Medicine and Health SciencesAn-Najah National UniversityNablus 44839Palestine Clinical Research Centre An-Najah National University HospitalNablus 44839Palestine

BACKGROUND Clostridioides(Clostridium)difficile(***)is still the most common cause of healthcare-associated diarrhoea and is increasing in prevalence as a communityacquired *** addition,the emergence of antibiotic resistance in *** can increase the likelihood of the disease developing and/or *** To provide an up-to-date picture of the trends in publications related to *** infection,together with specific insights into hot-button issues in this *** Publications on *** infections in the field of microbiology between 2001 and 2020 were identified from the Scopus database and Reference Citation *** indicators were determined,including the number and type of publications,countries,affiliations,funding agencies,journals and citation *** was used to determine research areas and hot-button issues by identifying recurring terms with a high relative occurrence in the title and *** A total of 8127 documents on‘***-associated diarrhoea’published between 2001 and 2020 were retrieved from the Scopus *** the last decade,there has been a significant almost fourfold increase in the number of published papers on this *** United States was among the countries(44.11%)with the most publications,and the most involved institution was the University of Leeds in the United Kingdom(2.50%).Three clusters of research were identified and included‘illness spectrum and severity,as well as the signs,symptoms and clinical pathogenesis of ***’;‘laboratory diagnosis and characterization of ***’and‘risk factors for *** infection’.CONCLUSION This study contains the most up-to-date and comprehensive data ever compiled in this *** international research and cross-institutional collaborations are needed to address more global *** concerns and to benefit from greater sharing of expertise,which will result in higher quality or more effective

关键词： Clostridioides Clostridium difficile Bibliometric Scopus VOSviewer Diarrhoea

Research landscape on COVID-19 and liver dysfunction: A bibliometric analysis

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World Journal of Gastroenterology 2023年第27期29卷 4356-4367页

作者： sa'ed H Zyoud Department of Clinical and Community Pharmacy College of Medicine and Health SciencesAn-Najah National UniversityNablus 44839Palestine Poison Control and Drug Information Center(PCDIC) College of Medicine and Health SciencesAn-Najah National UniversityNablus 44839Palestine Clinical Research Centre An-Najah National University HospitalNablus 44839Palestine

BACKGROUND The global spread of severe acute respiratory syndrome coronavirus 2,responsible for coronavirus disease 2019(COVID-19),poses a significant risk to public *** the respiratory issues initially associated with the condition,severe cases of COVID-19 can also lead to complications in other organs,including the *** with severe COVID-19 may exhibit various clinical signs of liver dysfunction,ranging from minor elevations in liver enzymes without symptoms to more serious cases of impaired liver *** damage is more commonly observed in patients with severe or critical forms of the *** To present the research landscape on COVID-19 and liver dysfunction while also offering valuable insights into the prominent areas of interest within this particular *** On 18 February 2023,Scopus was utilised to conduct a comprehensive exploration of the relationship between COVID-19 and the liver *** investigation encompassed the period from 1 January 2020 to 31 December *** sources were meticulously examined and organised in a Microsoft Excel 2013 spreadsheet,categorised by journal,institution,funding agency,country and citation *** version 1.6.18 was employed to explore the prominent topics and knowledge network related to the *** There were 2336 publications on COVID-19 and liver dysfunction analysed in this study,of which 558 were published in 2020,891 in 2021 and 887 in *** from 111 different countries participated in the retrieved *** United States contributed the most studies,with 497 documents,representing 21.28%of the total,followed by China with 393 documents(16.82%)and Italy with 255 documents(10.92%).In the context of research related to COVID-19 and the liver,co-occurrence analysis identified three distinct clusters of topics:(1)‘COVID-19 vaccines in liver transplant recipients’;(2)‘liver function tests as a predictor of the severity and clinical outcom

关键词： COVID-19 Bibliometric Scopus Vosviewer Liver

The effect of ethanol fuel dilution on oil performance and MoDTC tribofilms formation and composition

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Friction 2024年第9期12卷 2108-2125页

作者： Juan ruiz-ACERO Felipe KESSLER Henara COSTA Tiago COUSSEAU Polytechnic School Universidade de São PauloSão Paulo 05508-030Brazil School of Food and Chemistry Universidade Federal do Rio GrandeRio Grande 96203-000Brazil School of Engineering Universidade Federal do Rio GrandeRio Grande 96203-900Brazil Mechanical Engineering Department Univ.Tecnológica Federal do ParanáCuritiba 81280-340Brazil University of Newcastle CallaghanSW 2308Australia

Ethanol has emerged as a promising alternative to fossil fuels,but its use can lead to significant dilution in lubricants,particularly during cold start or heavy *** dilution can affect the performance of additives,including friction modifiers like molybdenum dithiocarbamate(MoDTC),which are designed to reduce friction under extreme contact *** research suggests that ethanol may impact the performance of MoDTC,prompting this study’s goal to investigate the effects of ethanol on MoDTC tribofilms and their friction response under boundary lubrication ***,reciprocating tribological tests were performed with fully formulated lubricants containing MoDTC with varying ethanol *** results indicate that a critical ethanol dilution level inhibits friction reduction by MoDTC activation,resulting in friction coefficients(COFs)similar to the base *** tested with simple mixtures of polyalphaolefin(PAO)+MoDTC showed increased COFs with added *** of tested surfaces using Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),and X-ray absorption spectroscopy near the edge structure(XANES)revealed the presence of sulfates,MoO_(3),MoS_(2),and MoS_(x)O_(y)compounds in the tribofilms formed on the surfaces,with and without ethanol diluted in the ***,the addition of ethanol increased the sulfates and MoO_(3)content of the tribofilms at the expense of friction-reducing compounds such as MoS_(2)and MoS_(x)O_(y).These findings suggest that ethanol dilution in lubricants containing MoDTC creates an oxygen-rich interfacial medium that favors the formation of compounds with insufficient friction-reducing capabilities.

关键词： molybdenum dithiocarbamate(MoDTC) ethanol tribofilm friction modifier additive lubricant