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Systematic variation of the sodium/sulfur promoter content on carbon-supported iron catalysts for the Fischer–Tropsch to olefins reaction

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Journal of Energy Chemistry 2016年第6期25卷 985-993页

作者： Martin Oschatz Nynke Krans Jingxiu Xie Krijn p.de jong University of Utrecht Group of Inorganic Chemistry and Catalysis Universiteitsweg

The Fischer–Tropsch to olefins（FTO） process is a method for the direct conversion of synthesis gas to lower C–Colefins. Carbon-supported iron carbide nanoparticles are attractive catalysts for this *** catalytic activity can be improved and undesired formation of alkanes can be suppressed by the addition of sodium and sulfur as promoters but the influence of their content and ratio remains poorly understood and the promoted catalysts often suffer from rapid deactivation due to particle growth. A series of carbon black-supported iron catalysts with similar iron content and nominal sodium/sulfur loadings of 1–30/0.5–5 wt% with respect to iron are prepared and characterized under FTO conditions at 1and 10 bar syngas pressure to illuminate the influence of the promoter level on the catalytic *** particles and promoters undergo significant reorganization during FTO operation under industrially relevant conditions. Low sodium content（1–3 wt%） leads to a delay in iron carbide formation. Sodium contents of 15–30 wt% lead to rapid loss of catalytic activity due to the covering of the iron surface with promoters during particle growth under FTO operation. Higher activity and slower loss of activity are observed at low promoter contents（1–3 wt% sodium and 0.5–1 wt% sulfur） but a minimum amount of alkali is required to effectively suppress methane and C–Cparaffin formation. A reference catalyst support（carbide-derived carbon aerogel） shows that the optimum promoter level depends on iron particle size and support pore structure.

关键词： Fischer–Tropsch to olefins synthesis C2–C4 olefins Iron catalysts promoters Carbon supports

Effect of initial nickel particle size on stability of nickel catalysts for aqueous phase reforming

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Journal of Energy Chemistry 2016年第2期25卷 287-294页

作者： Tomas van Haasterecht Marten Swart Krijn p.de jong Johannes Hendrik Bitter Inorganic Chemistry and Catalysis Utrecht University 3508 TB Utrecht The Netherlands Biobased Chemistry and Technology Wageningen University 6708 WG Wageningen The Netherlands

The deactivation behavior by crystallite growth of nickel nanoparticles on various supports（carbon nanofibers, zirconia, Si C, α-Al2O3 and γ-Al2O3） was investigated in the aqueous phase reforming of ethylene glycol. Supported Ni catalysts of ~10 wt% were prepared by impregnation of carbon nanofibers（CNF）,Zr O2, SiC, γ-Al2O3 and α-Al2O3. The extent of the Ni nanoparticle growth on various support materials follows the order CNF ~ ZrO2〉 SiC 〉 γ-Al2O3〉〉 α-Al2O3 which sequence, however, was determined by the initial Ni particle size. Based on the observed nickel leaching and the specific growth characteristics; the particle size distribution and the effect of loading on the growth rate, Ostwald ripening is suggested to be the main mechanism contributing to nickel particle growth. Remarkably, initially smaller Ni particles（~12 nm） supported on α-Al2O3 were found to outgrow Ni particles with initially larger size（~20 nm）. It is put forward that the higher susceptibility with respect to oxidation of the smaller Ni nanoparticles and differences in initial particle size distribution are responsible for this behavior.

关键词： Aqueous phase reforming particle growth Catalyst stability Ostwald ripening Leaching Nickel catalysts particle size effect Support effect

Erratum to: Assessment of oxide nanoparticle stability in liquid phase transmission electron microscopy

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Nano Research 2019年第10期12卷 2653-2653页

作者： Mark J.Meijerink Krijn p.de jong Jovana Zecevic Inorganic Chemistry and Catalysis Debye Institute of Nanomaterials ScienceUtrecht UniversityUniversiteitsweg 993584 CG UtrechtThe Netherlands

The article Assessment of oxide nanoparticle stability in liquid phase transmission electron microscopy written by Mark ***,Krijn *** jong,and Jovana Zecevic,was originally published electronically on the publisher's internet portal(currently SpringerLink)on 22 May 2019 without open *** copyright of the article changed on 3 June 2019 to c The Author(s)2019 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License(http://***/licenses/by/4.0/),which permits use,duplication,adaptation,distribution and reproduction in any medium or format,as long as you give appropriate credit to the original author(s)and the source,provide a link to the Creative Commons license and indicate if changes were made.

关键词： stability license phase

demonstration of tantalum as a structural material for MEMS thermal actuators

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Microsystems & Nanoengineering 2021年第1期7卷 85-97页

作者： Longchang Ni Ryan M.pocratsky Maarten p.de Boer CMU Mechanical Engineering dept. 5000 Forbes Ave.PittsburghPA 15213USA present address:Fischione Instruments 9003 Corporate CirExportPA 15632USA

This work demonstrates the processing,modeling,and characterization of nanocrystalline refractory metal tantalum(Ta)as a new structural material for microelectromechanical system(MEMS)thermal actuators(TAs).Nanocrystalline Ta films have a coefficient of thermal expansion(CTE)and Young’s modulus comparable to bulk Ta but an approximately ten times greater yield *** mechanical properties and grain size remain stable after annealing at temperatures as high as 1000°*** has a high melting temperature(Tm=3017℃)and a low resistivity(ρ=20µΩcm).Compared to TAs made from the dominant MEMS material,polycrystalline silicon(polysilicon,Tm=1414℃,ρ=2000µΩcm),Ta TAs theoretically require less than half the power input for the same force and displacement,and their temperature change is half that of *** TAs operate at a voltage 16 times lower than that of other TAs,making them compatible with complementary metal oxide semiconductors(CMOS).We selectα-phase Ta and etch 2.5-μm-thick sputterdeposited films with a 1μm width while maintaining a vertical sidewall profile to ensure in-plane movement of TA *** is 25 times thicker than the thickest reactive-ion-etchedα-Ta reported in the technical *** stress sensitivities to sputter parameters and to hydrogen incorporation are investigated and ***,a V-shaped TA is fabricated and tested in *** conventional actuation by Joule heating and passive self-actuation are as predicted by models.

关键词： thermal structural thick

In silico analysis of lncRNA-miRNA-mRNA signatures related to Sorafenib effectiveness in liver cancer cells

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World Journal of Gastroenterology 2025年第3期31卷 84-102页

作者： patricia de la Cruz-Ojeda Ester parras-Martínez Raquel Rey-pérez Jordi Muntané Functional Genomics of Solid Tumors Laboratory Centre de Recherche des CordeliersParis 75006France department of Oncology Surgery Cell Therapy and Organ TransplantationInstitute of Biomedicine of SevilleVirgen del Rocio University HospitalSeville 41013Spain Biomedical Research Center for Hepatic and Digestive Diseases CIBERehdMadrid 28029Spain department of Medical physiology and Biophysics University of SevilleSeville 41009Spain

BACKGROUND Hepatocellular carcinoma(HCC)is the most common subtype of primary liver cancer with varied incidence and ep.demiology *** is still a recommended treatment for a large proportion of patients with advanced *** patterns of treatment responsiveness have been identified in differentiated hepatoblastoma HepG2 cells and metastatic HCC SNU449 *** To define the long non-codingRNA-microRNA-mRNA(lncRNA-miRNA-mRNA)predicted signatures related to selected hallmarks of cancer(apoptosis,autophagy,cell stress,cell dedifferentiation and invasiveness)in RNAseq studies using Sorafenib-treated HepG2 and SNU449 *** available software analyses allowed us to establish the lncRNA-miRNA-mRNA regulatory axes following treatment in HepG2 and SNU449 *** HepG2 and SNU449 cells were treated with Sorafenib(10μmol/L)for 24 *** RNA,including small and long RNA,was extracted with a commercial miRNeasy *** was carried out for the identification of changes in lncRNA-miRNA-mRNA regulatory *** MALAT,THAp9-AS1 and SNGH17 appeared to coordinately regulate miR-374b-3p and miR-769-5p that led to upregulation of SMAD7,TIRARp,TFAp4 and FAXDC2 in HepG2 ***12,EpB41 L4A-AS1,LINC01578,SNHG12 and GAS5 interacted with let-7b-3p,miR-195-5p and VEGFA in SNU449 *** axes MALAT1/hsamir-374b-3p/SMAD7 and MALAT1/hsa-mir-769-5p/TFAp4 were of high relevance for Sorafenib response in HepG2 cells,whereas pVT1/hsa-miR-195-5p/VEGFA was responsible for the differential response of SNU449 cells to Sorafenib *** Critical lncRNAs acting as sponges of miRNA were identified that regulated mRNA expression,whose proteins mainly increased the antitumor effectiveness of the treatment(SMAD7,TIRARp,TFAp4,FAXDC2 and ADRB2).However,the broad regulatory axis leading to increased VEGFA expression may be related to the side effect of Sorafenib in SNU449 cells.

关键词： Cell culture Hepatocellular carcinoma Non-coding RNA RNAseq Sorafenib

Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystems 2024年第1期11卷 110-119页

作者： J.Touche C.Calvaruso p.de Donato M.-p.Turpault INRAE BEFF-54000NancyFrance UMR 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the coming decades in Western Europe may disturb forest biogeochemical cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the maintenance of tree nutrition are poorly *** experiment in a beech forest in Meuse(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim was to identify potential nutritional consequences of droughts for *** nutrient dynamics,including resorption,chemistry of green and senesced leaves,foliar absorption and leaching in mature beech stands from 2012 to 2019 allowed us to compare the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by almost a third of the potassium(K)partitioning to resorption(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the coming decades,there will be a risk of potassium deficiency in trees,as already observed in a rainfall exclusion experiment on the same study *** foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(p)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is more likely to improve tree *** calcium(Ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought Beech forest Canopy Resorption Foliar leaching Senesced leaves Nutrition

GREEN BUILDING MATERIALS:A REVIEW OF STATE OF THE ART STUDIES OF INNOVATIVE MATERIALS

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Journal of Green Building 2017年第4期12卷 141-161页

作者： p.de Luca I.Carbone J.B.Nagy department of Ingegneria per l’Ambiente ed il Territorio ed Ingegneria Chimica University of CalabriaRendeItaly department of Ingegneria Civile University of CalabriaRendeItaly

***is paper presents a comprehensive survey of the latest international publications(2012-2017)regarding innovative and environmentally sustainable materials that reduce the production of *** is recognised that world construction is responsible for substantial amounts of harmful *** particular,the survey collected data on new sustainable solutions and innovative materials,such as cement,wood,glass and ceramics that are essential to minimize the environmental impact of buildings on the ecosystem and to reduce the consumption of natural resources.erefore,the paper’s intent is to give an overview of the current state of the art and research in theeld of bio-building,gathering information on the environmental impacts of these innovative materials and listing the benets that can be obtained with their *** findings of this study support the growing importance of grecn building as a componcnt of the whole construction market and provide a benchmark against which to mcasure futurc changes in the industry over time.

关键词： innovative materials sustainable materials bio-building green building

phylogeny of the industrial relevant,thermophilic genera Myceliophthora and Corynascus

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Fungal Diversity 2012年第1期52卷 197-207页

作者： Joost van den Brink Robert A.Samson Ferry Hagen Teun Boekhout Ronald p.de Vries CBS-KNAW Fungal Biodiversity Centre P.O.Box 851673508 AD UtrechtThe Netherlands

Species of the genus Myceliophthora and its teleomorph Corynascus have attracted increasing interest due to their potential to produce thermostable *** study re-assessed the phylogenetic relationship of 49 isolates of nine species belonging to Myceliophthora and *** species,***,was shown not to belong to the genus Myceliophthora and should be placed in the genus *** other species belonged to two phylogenetic clusters:mesophilic fungi with the type species *** and ***,and thermophilic fungi with ***,*** and *** phylogenetic data provides no clear separation of the two genera Corynascus and *** avoid confusion in future taxonomic studies,it is proposed that all existing Corynascus species be renamed to Myceliophthora,which is the old name and the one more frequently ***,this study identified two groups within the isolates listed as *** and assigned one group(five isolates)to *** based on AFLp analysis and mating *** study provides new insights into the genetic differences within the genus Myceliophthora and will therefore be essential for the interpretation of future genomic and physiological studies of these species.

关键词： Myceliophthora Corynascus Thermophiles M.heterothallica M.thermophila.Thermophilic fungi Multigene phylogeny AFLp analysis Mating behavior

A Rapid Adaptation Approach for Dynamic Air‑Writing Recognition Using Wearable Wristbands with Self‑Supervised Contrastive Learning

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Nano-Micro Letters 2025年第2期17卷 417-431页

作者： Yunjian Guo Kunpeng Li Wei Yue Nam‑Young Kim Yang Li Guozhen Shen jong‑Chul Lee department of Electronic Convergence Engineering Kwangwoon UniversitySeoul 01897South Korea Radio Frequency Integrated Circuit(RFIC)Bio Centre Kwangwoon UniversitySeoul 01897South Korea department of Electronic Engineering Kwangwoon UniversitySeoul 01897South Korea School of Microelectronics Shandong UniversityJinan 250101People’s Republic of China State Key Laboratory of Integrated Chips and Systems Fudan UniversityShanghai 200433People’s Republic of China School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081People’s Republic of China

Wearable wristband systems leverage deep learning to revolutionize hand gesture recognition in daily *** existing approaches that often focus on static gestures and require extensive labeled data,the proposed wearable wristband with selfsupervised contrastive learning excels at dynamic motion tracking and adapts rapidly across multiple *** features a four-channel sensing array composed of an ionic hydrogel with hierarchical microcone structures and ultrathin flexible electrodes,resulting in high-sensitivity capacitance *** wireless transmission from a Wi-Fi module,the proposed algorithm learns latent features from the unlabeled signals of random wrist ***,only few-shot labeled data are sufficient for fine-tuning the model,enabling rapid adaptation to various *** system achieves a high accuracy of 94.9%in different scenarios,including the prediction of eight-direction commands,and air-writing of all numbers and *** proposed method facilitates smooth transitions between multiple tasks without the need for modifying the structure or undergoing extensive task-specific *** utility has been further extended to enhance human–machine interaction over digital platforms,such as game controls,calculators,and three-language login systems,offering users a natural and intuitive way of communication.

关键词： Wearable wristband Self-supervised contrastive learning Dynamic gesture Air-writing Human-machine interaction