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nano Research 2011年第7期4卷 666-674页

作者： tiago luis da Silva Laudemir carlos Varanda Colloidal materials Group Instituto de Quimica de Sao Carlos Universidade de Sao Paulo--USP Sao Carlos PO Box 780 13566-590 Brazil

the synthesis and self-assembly of tetragonal phase-containing L10-Fe55Pt45 nanorods with high coercive field is described. the experimental procedure resulted in a tetragonal/cubic phase ratio close to 1：1 for the as-synthesized nanoparticles. Using different surfactant/solvent proportions in the process allowed control of particle morphology from nanospheres to nanowires. Monodisperse nanorods with lengths of 60 ＋ 5 nm and diameters of 2-3 nm were self-assembled in a perpendicular oriented array onto a substrate surface using hexadecylamine as organic spacer. magnetic alignment and properties assigned, respectively, to the shape anisotropy and the tetragonal phase suggest that the self-assembled materials are a strong candidate to solve the problem of random magnetic alignment observed in FePt nanospheres leading to applications in ultrahigh magnetic recording （UHMR） systems capable of achieving a performance of the order of terabits/in2.

关键词： magnetic materials data storage FePt nanorods self-assembl~ perpendicular magnetic alignment

Woodland Mediterranean birds can resist a dry extreme cold wave

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Current Zoology 2014年第4期60卷 429-437页

作者： Sara VILLEn-PEREZ luis M. caRRAScaL Department of Biogeography and Global Change Museo Nacional de Ciencias Naturales (CSIC) C/Jos6 Guti6rrez Abascal 228006 Madrid Spain

the ecological consequences of climate extreme events are still poorly understood, especially those related to cold episodes. Winter cold spells might imperil the energy balance of small passerines, thus compromising their survivorship. Here we analyze how the abundance and habitat use of three tree-gleaning passerine species wintering in a montane oakwood of central Spain at ca. 1,300 m a.s.1, was influenced by the cold wave that hit Europe in February 2012. We monitored temperature, wind and the relative abundance of great tit Parus major, blue tit Cyanistes caeruleus and long-tailed tit Aegithalos caudatus in 15 plots throughout three periods： before, during and after the cold wave. Our results clearly rule out widespread mortality and temporal migration of the studied passerine populations, as the abundance of these species did not diminish during the cold wave. Moreover, the species usually foraging higher in the tree canopy -and thus more exposed to windmoved to the less windy woodland plots （long-tailed tit） and reduced their foraging height above ground during the cold wave （long-tailed tit and blue tit）, probably to mitigate the deleterious effects of wind chill. therefore, these forest birds were able to cope with a dry cold wave that was statistically extreme in terms of temperature and wind chill, according to the historic climate records of the region. It seems that, at least when foraging substrates are not heavily covered by snow or ice, Mediterranean birds can resist an extreme cold wave [Current Zoology 60 （4）： 429-437, 2014].

关键词： Cold wave Harsh weather Mediterranean oakwoods temperature tree-gleaning birds Wind chill

灰分中碱和碱土金属对生物质快速热解生物油组分的影响

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燃料化学学报（中英文） 2024年第7期52卷 967-975页

作者：丁紫霞蔡博岑珂慧陈登宇马中青浙江农林大学化学与材料工程学院浙江杭州311300 南京林业大学材料科学与工程学院江苏南京210037

生物质灰分中的碱和碱土金属(AAEMs)对快速热解生物油的产率和组分分布具有显著影响。本研究选取玉米秸秆为原料,研究梯级脱灰预处理(蒸馏水、醋酸铵和盐酸)对AAEMs的选择性脱除及其生物油组分的影响,研究了碱和碱土金属类别(K、ca、na... 详细信息

生物质灰分中的碱和碱土金属(AAEMs)对快速热解生物油的产率和组分分布具有显著影响。本研究选取玉米秸秆为原料,研究梯级脱灰预处理(蒸馏水、醋酸铵和盐酸)对AAEMs的选择性脱除及其生物油组分的影响,研究了碱和碱土金属类别(K、ca、na和Mg)、盐质量分数(0.5%、2.5%、5%)和不同钾盐的酸根(SO_(4)^(2-)、nO_(3)^(-)、CO_(3)^(2-)、HCO_(3)^(-)、AC^(-)、po_(4)^(3-))对生物油组分的影响。结果表明,在梯级脱灰预处理过程中,随着脱灰溶液酸性程度加深,AAEMs的脱除率逐渐上升,根据AAEMs在梯级脱灰过程中的选择性脱除规律,可将其在生物质中的赋存形态分为水溶性(K)、离子交换性(ca和Mg)和酸溶性(na)等形态。经过碱和碱土金属盐浸渍后,AAEMs将起到催化剂的作用,促进热解中间产物左旋葡聚糖的二次降解,导致其相对含量显著降低,形成更多的呋喃和酮类等轻质含氧化合物,导致2,3-二氢苯并呋喃、酮类和长链烷烃等组分的含量显著增加。不同钾盐酸根离子对脱水糖的二次裂解反应及木质素芳基醚键和酚羟基的裂解反应具有较大的影响,根据酸根的酸性强弱,对脱水糖裂解反应的影响大小顺序为HCO_(3)^(-)>CO_(3)^(2-)>AC^(-)>po_(4)^(3-)>Cl^(-)>nO_(3)^(-)>SO_(4)^(2-),而对木质素芳基醚键和酚羟基的裂解反应影响大小顺序为CO_(3)^(2)->Cl^(-)>HCO_(3)^(-)po_(4)^(3-)≈AC^(-)>SO_(4)^(2-)≈nO_(3)^(-).

关键词：生物质脱灰预处理碱和碱土金属快速热解生物油

A techno-economic and life cycle assessment for the production of green methanol from CO_(2): catalyst and process bottlenecks

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Journal of Energy Chemistry 2022年第5期31卷 255-266页

作者： tomas Cordero-Lanzac Adrian Ramirez Alberto navajas Lieven Gevers Sirio Brunialti luis MGandía Andrés t.Aguayo S.mani Sarathy Jorge Gascon Department of Chemical Engineering University of the Basque Country(UPV/EHU)PO Box 64448080 BilbaoSpain King Abdullah University of Science and technology KAUST Catalysis Center(KCC)Advanced Catalytic MaterialsThuwal 23955Saudi Arabia Department of Science Public University of Navarre(UPNA)Arrosadía Campus s/n31006 PamplonaSpain Institute for Advanced materials and mathematics(Inamat2) Universidad Pública de Navarra(UPNA)Edificio Jerónimo de AyanzCampus de ArrosadiaPamplona-Iruña 31006Spain King Abdullah University of Science and technology Clean Combustion Research Center(CCRC)Thuwal 23955Saudi Arabia

the success of catalytic schemes for the large-scale valorization of CO_(2) does not only depend on the development of active,selective and stable catalytic materials but also on the overall process *** we present a multidisciplinary study(from catalyst to plant and techno-economic/lifecycle analysis)for the production of green methanol from renewable H2 and CO_(2).We combine an in-depth kinetic analysis of one of the most promising recently reported methanol-synthesis catalysts(InCo)with a thorough process simulation and techno-economic *** then perform a life cycle assessment of the simulated process to gauge the real environmental impact of green methanol production from CO_(2).Our results indicate that up to 1.75 ton of CO_(2) can be abated per ton of produced methanol only if renewable energy is used to run the process,while the sensitivity analysis suggest that either rock-bottom H2 prices(1.5$kg1)or severe CO_(2) taxation(300$per ton)are needed for a profitable methanol ***,we herein highlight and analyze some critical bottlenecks of the *** attention has been paid to the contribution of H2 to the overall plant costs,CH4 trace formation,and purity and costs of raw *** addition to providing important information for policy makers and industrialists,directions for catalyst(and therefore process)improvements are outlined.

关键词： CO_(2) Methanol Kinetic modeling Process simulation Life cycle assessment

A new Member of the thioredoxin Reductase Family from Early Oxygenic Photosynthetic Organisms

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Molecular Plant 2017年第1期10卷 212-215页

作者： Rubén M. Buey Sergio Galindo-trigo luis López-maury Adrián Velázquez-ca.poy José luis Revuelta F. Javier Florencio José M. de Pereda Peter Schürmann Bob B. Buchanan Monica Balsera Department Microbiología y Genética Universidad de Salamanca Salamanca 37007 Spain Instituto de Recursos naturales y Agrobiología de Salamanca (IRnASA-CSIC) Salamanca 37008 Spain Instituto de Bioquímica Vegetal y Fotosíntesis (CSIC-Universidad de Sevilla) Seville 41092 Spain Institute of Biocomputation and Physics of Complex Systems (BIFI) University of Zaragoza Zaragoza 50018 Spain Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca) Salamanca 37007 Spain Laboratoire de Biologie Moléculaire et Cellulaire Université de Neuchâtel Neuchâtel 2000 Switzerland Department of Plant and Microbial Biology University of California Berkeley CA 94720 USA

Dear Editor,thioredoxins （trxs） are key components of the redox system that regulates the activity of a spectrum of target proteins through dithiol-disulfide exchange reactions. trxs are reduced by mem- bers of the trx reductase （tR） family （Jacquot et al., 2009）. nADP-dependent thioredoxin reductases （ntRs）, the most com-mon type, belong to the family of dimeric pyridine nucleotide disul-fide oxidoreductase flavoproteins that use nADPH as the source of reducing equivalents.

关键词： thioredoxin Early Organisms

Changes in Gene Expression in needles and Stems of Pinus radiata Rootstock Plants of Different Ontogenic Age

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American Journal of Plant Sciences 2016年第8期7卷 1205-1216页

作者： carolina Alvarez luis Valledor Patricia Sáez Rodrigo Hasbún manuel Sánchez-Olate maría Jesús cañal Darcy Ríos Laboratorio de Cultivo de tejidos Vegetales Facultad de Ciencias Forestales y Centro de Biotecnología Universidad de Concepción Concepción Chile Centro tecnológico de la Planta Forestal (CtPF) Instituto Forestal (INFOR) Sede Bío-Bío Chile Laboratories of Adaption Biotechnologies Global Change Research Centre Academy of Sciences of the Czech Republic Brno Czech Republic Plant Physiology Epiphysage Research Group Biology of Organisms and Systems Department Faculty of Biology University of Oviedo Oviedo Spain

A major problem in forest clonal productivity is the loss of morphogenetic capability with the increasing age of plants. However, despite of the importance of loss of morphogenetic competence, very little research has been done about the underlying mechanisms involved in this process. For this reason, a gene expression analysis using dot blot technique was performed in needles and stems of 1- and 3-year old Pinus radiata rootstock plants with a proved decrease in morphogenetic competence. needles of one year old rootstock plants showed a higher number of up-regulated in genes mainly corresponding to photosynthesis and protein synthesis, degradation and modification, reflecting a higher number of active pathways in younger hedges, contrary to the older ones. Gene expression profiles found in stems are in agreement with those found in needles, indicating more active pathways in younger rootstock plants than in older ones. Several transcripts regulating transcription and translation were up-regulated in young competent tissues. three-year-old stems presented an increase in the expression of an ethylene response factor, involved in plant organ senescence, indicating that pathways involved in senescence and ageing might inhibit the adventitious root formation, as in the older cuttings.

关键词： Plant Ageing Gene Expression Morphogenetic Competence Pinus radiate

Human umbilical artery smooth muscle exhibits a 2-APBsensitive capacitative contractile response evoked by vasoactive substances and expresses mRnAs for StIM, Orai and tRPC channels

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BIOCELL 2012年第2期36卷 73-81页

作者： AnA ROCÍO ROLDÁn PALOMO PEDRO maRtIn ALEJAnDRO REBOLLEDO nICOLÁS EnRIQUE luis E.FLORES VERÓnIca MILESI GInFIV–Grupo de Investigación en Fisiología Vascular Facultad de Ciencias ExactasUniversidad Nacional de La Plata.Argentina CEnEXA–Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La PlataCentro Colaborador OPS/OMS)Facultad de Ciencias MédicasUniversidad Nacional de La Plata.Argentina

After depletion of intracellular ca^(2+)stores the capacitative response triggers an extracellular ca^(2+)influx through store-operated channels(SOCs)which refills these *** objective was to explore if human umbilical artery smooth muscle presented this response and if it was involved in the mechanism of serotonin-and histamine-induced *** ca^(2+)depletion by a ca^(2+)-free extracellular solution followed by ca^(2+)readdition produced a contraction in artery rings which was inhibited by the blocker of Orai and tRPC channels 2-aminoethoxydiphenyl borate(2-APB),suggesting a capacitative *** presence of 2-APB the magnitude of a second paired contraction by serotonin or histamine was significantly less than a first one,likely because 2-APB inhibited store refilling by capacitative ca^(2+)entry.2-APB inhibition of sarcoplasmic reticulum ca^(2+)release was excluded because this blocker did not affect serotonin force development in a ca^(2+)-free *** PCR technique showed the presence of mRnAs for StIM proteins(1 and 2),for Orai proteins(1,2 and 3)and for tRPC channels(subtypes 1,3,4 and 6)in the smooth muscle of the human umbilical ***,this artery presents a capacitative contractile response triggered by stimulation with physiological vasoconstrictors and expresses mRnAs for proteins and channels previously identified as SOCs.

关键词： human umbilical artery capacitative response tRPC channels serotonin histamine

Schisandrin B decreases the sensitivity of mitochondria to calcium ioninduced permeability transition and protects against ischemia-reperfusion injury in rat hearts

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Acta Pharmacologica Sinica 2007年第10期28卷 1559-1565页

作者： po-yee CHIU Hoi-yan LEUnG Ada HL SIU Michel KtpoOn Kam-ming KO Department of Biochemistry Hong Kong University of Science and technology Hong Kong SAR China

Aim:In order to elucidate the molecular mechanism underlying the cardioprotectionafforded by schisandrin B （Sch B）,the effect of Sch B treatment on the sensitivityof mitochondria to ca2+-stimulated permeability transition （Pt） was investigatedin rat hearts under normal and ischemia-reperfusion （I-R） ***:Myocardial I-R injury caused an increase in the sensitivity of mitochondria toca2+-stimulated Pt in *** enhanced sensitivity to mitochondrial Pt wasassociated with increases in mitochondrial ca2+content as well as the extent ofreactive oxidant species production in vitro and cytochrome c release in *** cardioprotection afforded by Sch B pretreatment against I-R-induced injurywas paralleled by the decrease in the sensitivity of myocardial mitochondria toca2+-stimulated Pt,particularly under I-R ***:the resultssuggest that Sch B treatment increases the resistance of myocardial mitochondriato ca2+-stimulated Pt and protects against I-R-induced tissue injury.

关键词： schisandrin B mitochondria permeability transition calcium myocardial ischemiareperfusion

Surface Water Quality Profiling Using Physicochemical Parameters in Open Defecation Free and non-Open Defecation Free Local Government Areas in Benue State, nigeria

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Open Journal of Modern Hydrology 2024年第3期14卷 174-191页

作者： Moses t. Asoo Celestine U. Aguoru Innocent O. Ogbonna Hyacinth O.A. Oluma Benue State Ministry of Health Makurdi Nigeria Department of Plant Science and Biotechnology College of Biological Sciences Joseph Sarwuan Tarka University Makurdi Nigeria Department of Microbiology College of Biological Sciences Joseph Sarwuan Tarka University Makurdi Nigeria

Physicochemical parameters of surface water sources in the study of local government areas (LGAs) were assessed using standard procedures. the mean physicochemical parameters for pH (5.49), nO2 (0.23 mg/L), SO4 (0.77 mg/L), na (28.72 mg/L), ca (28.94 mg/L), Mg (17.50 mg/L), Cl (11.65 mg/L), tSS (6.27 mg/L), tDS (104.23 mg/L), BOD (2.83 mg/L) and F (0.87 mg/L) were below WHO standards irrespective of their defecation status. the values for electrical conductivity (EC) (2770.50 µs/cm, turbidity (481.24 ntU), dissolved oxygen (DO) (5.32 mg/L), chemical oxygen demand (COD) (445.50 mg/L), K (125.06 mg/L), po4 (0.78 mg/L) and Fe (0.57 mg/L) were above the WHO limits for safe water. Higher EC and COD values obtained in the study is evidence of pollution of the water sources by organic matter.

关键词： Open Defecation Surface Water Water Quality Standard Physicochemical Parameters

Online risk‑based portfolio allocation on subsets of crypto assets applying a prototype‑based clustering algorithm

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Financial Innovation 2023年第1期9卷 797-836页

作者： luis Lorenzo Javier Arroyo Faculty of Statistic Studies Complutense UniversityAvda.Puerta de Hierros/n28040 MadridSpain

Mean-variance portfolio optimization models are sensitive to uncertainty in risk-return estimates,which may result in poor out-of-sample *** particular,the estimates may suffer when the number of assets considered is high and the length of the return time series is not sufficiently *** is precisely the case in the cryptocur-rency market,where there are hundreds of crypto assets that have been traded for a few *** propose enhancing the mean-variance(MV)model with a pre-selection stage that uses a prototype-based clustering algorithm to reduce the number of crypto assets considered at each investment *** the pre-selection stage,we run a prototype-based clustering algorithm where the assets are described by variables representing the profit-risk *** prototypes of the clustering partition are auto-matically examined and the one that best suits our risk-aversion preference is *** then run the MV portfolio optimization with the crypto assets of the selected *** proposed approach is tested for a period of 17 months in the whole cryp-tocurrency market and two selections of the cryptocurrencies with the higher market capitalization(175 and 250 cryptos).We compare the results against three methods applied to the whole market:classic MV,risk parity,and hierarchical risk parity *** also compare our results with those from investing in the market index *** simulation results generally favor our proposal in terms of profit and risk-profit financial *** result reaffirms the convenience of using machine learning methods to guide financial investments in complex and highly-volatile environments such as the cryptocurrency market.

关键词： Fintech Mean-variance Cryptocurrency Electronic market portfolio allocation model Clustering