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Al-ga-In-Sn-Si合金阳极及海水溶解氧电池的电化学性能

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应用化学 2024年第5期41卷 703-711页

作者：吴厚燃侯春明段体岗马力张海兵王金涛武汉理工大学材料复合新技术国家重点实验室武汉430070 洛阳船舶材料研究所海洋腐蚀与防护全国重点实验室青岛266237 中国船舶科学研究中心无锡214082

通过ga、In和Sn低熔点合金元素改性,成功制备了高负电位高活化Al-ga-In-Sn-Si合金阳极,通过材料表征和电化学测试研究了Al-ga-In-Sn-Si合金的腐蚀行为和电化学性能,并与碳纤维刷-石墨烯-铂(Pt-G@CFB)催化阴极搭建了海水溶解氧电池,考察... 详细信息

通过ga、In和Sn低熔点合金元素改性,成功制备了高负电位高活化Al-ga-In-Sn-Si合金阳极,通过材料表征和电化学测试研究了Al-ga-In-Sn-Si合金的腐蚀行为和电化学性能,并与碳纤维刷-石墨烯-铂(Pt-G@CFB)催化阴极搭建了海水溶解氧电池,考察了室内静态海水环境和实际海洋环境下电池不同恒电阻的长周期放电性能。结果表明,Al-ga-In-Sn-Si合金的自腐蚀电位为-1.613 V(vs.Ag/AgCl),自腐蚀电流密度为1.431 mA/cm^(2)。随着负载电阻的增加,电池电压上升,在室内静态和实海动态海水中2000Ω的负载下海水溶解氧电池平均放电电压最高,分别为1.73和1.78 V,在1000Ω的负载下平均能量密度最大,分别为549.85和653.44 Wh/kg。

关键词： Al-ga-In-Sn-Si合金阳极海水溶解氧电池电化学性能放电行为

Al-Zn-In-Mg-ti-ga-Mn牺牲阳极在极地低温环境中的电化学性能

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中国有色金属学报 2023年第4期33卷 1209-1219页

作者：张一晗张海兵辛永磊黄嵘段体岗马力李祯中国船舶集团有限公司第七二五研究所海洋腐蚀与防护重点实验室青岛266237 中国极地研究中心(中国极地研究所) 上海200136

基于前期牺牲阳极材料研究成果,对极地低温环境专用Al-Zn-In-Mg-ti-ga-Mn牺牲阳极开展模拟服役环境下的电化学性能测试,通过完整周期的“雪龙号”极地航行试验考察极端环境因素对牺牲阳极电化学性能的影响,采用高倍率扫描电镜等手段观... 详细信息

基于前期牺牲阳极材料研究成果,对极地低温环境专用Al-Zn-In-Mg-ti-ga-Mn牺牲阳极开展模拟服役环境下的电化学性能测试,通过完整周期的“雪龙号”极地航行试验考察极端环境因素对牺牲阳极电化学性能的影响,采用高倍率扫描电镜等手段观测材料腐蚀产物特征和表面微观形貌。结果表明:在极端环境因素影响下,阳极材料的活化和溶解行为发生变化,海水环境中较高的溶解氧含量和盐度削弱了低温条件对离子运动的影响,阳极材料自腐蚀程度下降,阴极去极化反应得到遏制,阳极表面活化溶解速率和活性金属沉积速率得到提升,表面钝化膜的更新动态平衡得到有效维持,牺牲阳极在极地海洋环境中表现出良好的阴极保护性能。

关键词：极地环境铝合金阳极阴极保护电化学性能

Intracranial Suppurations in Togo: Etiologies and Treatment

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Open Journal of Modern Neurosurgery 2023年第1期13卷 9-17页

作者： Essossinam Kpélao Messan H. Ahanogbé Komi Egu Agbéko K. Doléagbénou Kader Moumouni Assila Komlanvi Kossi K. Ségbédji Solim Bakondé Dzidoula Lawson Abaltou Bawoubad Abdoulaye Hima-Maïga Katanga A. Békéti Neurosurgery Unit Sylvanus Olympio Hospital Lomé Togo Neurosurgery Unit Kara University Hospital Kara Togo Infectious Disease Unit Sylvanus Olympio Hospital Lomé Togo

Objective: Intracranial suppurations are a cosmopolitan pathology whose prevalence depend of the region of the world. They are mostly caused by otolaryngological infections. Despite the progress, they remain serious diseases in Africa. The objective of this study was to report the epidemiology, clinical and etiological aspects of intracranial suppurations in Togo. Method: This was a retrospective and descriptive study carried out from January 1, 2012 to December 31, 2020 including all cases of intracranial suppuration treated in the neurosurgery unit of Sylvanus Olympio university hospital in lomé. The evolution was evaluated at discharge, at 3 and 6 months after. Results: We collected 185 cases of intracranial suppuration. The average age of the patients was 12.6 years with a male predominance (72.4%). The main clinical signs were the infectious syndrome (92.4%), intracranial high pressure (51.4%), focal deficit (38.4%) and seizures (20.5%). An otolaryngological infections history was noted within 3 months in 72.4%. The brain CT scan noted a predominance of empyema (63.8%) mostly subdural (64.4%). Radiological sinusitis was found in 57.3%. We identified etiology in 69.2% predominated by otolaryngological causes. Patients received medical and surgical treatment in 77.3%. The bacteriology was positive only in 7 cases. The mortality rate was 15.1%, mostly no operated cases (78.6%). At 6 months 84% recovered without sequelae. The predictive prognostic factors for mortality were: coma (p 0.001), absence of surgical treatment (p 0.02). Conclusion: Intracranial suppuration remains frequent in our country, mainly due to otolaryngological pathologies. The clinical presentation is not always specific and Bergman’s triad is rarely complete. The results of treatment are good if it is early.

关键词： Intracranial Abscess Empyema Togo

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npj Computational Materials 2021年第1期7卷 1474-1480页

作者： Iaroslav gaponenko loïc Musy Neus Domingo Nicolas Stucki Albert Verdaguer Nazanin Bassiri-Gharb Patrycja Paruch Department of Quantum Matter Physics University of GenevaGenevaSwitzerland G.W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGAUSA catalan Institute of Nanoscience and Nanotechnology(ICN2) CSIC and BISTCampus UABBarcelonaSpain University of Applied Sciences and Arts Western Switzerland(HES-SO/HEPIA) GenevaSwitzerland Institut de Ciència de Materials de Barcelona(ICMAB) CSICCampus UABBarcelonaSpain School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGAUSA

Electrochemical phenomena in ferroelectrics are of particular interest for catalysis and sensing applications,with recent studies highlighting the combined role of the ferroelectric polarisation,applied surface voltage and overall switching history.Here,we present a systematic Kelvin probe microscopy study of the effect of relative humidity and polarisation switching history on the surface charge dissipation in ferroelectric Pb(Zr_(0.2)ti_(0.8))O_(3)thin films.We analyse the interaction of surface charges with ferroelectric domains through the framework of physically constrained unsupervised machine learning matrix factorisation,Dictionary Learning,and reveal a complex interplay of voltage-mediated physical processes underlying the observed signal decays.Additional insight into the observed behaviours is given by a Fitzhugh–Nagumo reaction–diffusion model,highlighting the lateral spread and charge passivation process contributors within the Dictionary Learning analysis.

关键词： ferroelectric charge film

Lamprophyre Rocks in the Nassara Gold Deposit, Southwest Burkina Faso: Characteristics and Implication for Mining Exploration

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Open Journal of Geology 2023年第12期13卷 1291-1311页

作者： Pascal Ouiya Adama Ouédraogo Yaméogo Sâga Sawadogo Séta Naba Ecole Normale Supérieure (ENS) Institut Sciences et Technologie (IST) Ouagadougou Burkina Faso Laboratoire Géosciences et Environnement (LaGE) Earth Sciences Department Ouagadougou Burkina Faso University Norbert ZONGO (UNZ) Koudougou Burkina Faso

The lamprophyres are late dykes that cut the formations hosting the gold mineralization in the Nassara deposit. They are geographically and spatially related to most orogenic gold deposits. It is with the aim of characterizing them and seeing their implications for exploration that this work is carried out. To achieve our objective, petrographic studies and chemical analyses of minerals (pyroxenes, amphiboles, feldspars, chromite) and geochemical analyses of total rock were carried out. These studies have enabled us to classify the Nassara lamprophyres as calc-alkaline lamprophyres of the spessartite type. The Cr, Co, Ni and Mg enrichment of these rocks would indicate a depleted mantle source, with LILE enrichment by fluids probably related to metasomatic activity. The various diagrams show that they are depleted in HREE and enriched in LREE. The high Nb/Ta ratios in our data indicate metasomatic activity probably linked to amphibole and rutile in the mantle prior to melting. The geodynamic context of spessartite-type lamprophyres indicates a signature linked to late-orogenic to post-collisional subduction. They are late-orogenic to post-collisional lamprophyres enriched in compatible elements (Cr, Ni, Co) and display a negative Ta-Nb-ti (TNT) anomaly. The frequent association of these lamprophyre dykes with the deposits does not indicate the source of the gold for these deposits, but rather zones of crustal permeability capable of draining hydrothermal fluids at the time of emplacement. Good mapping of lamprophyre dykes, especially in shear zones, could therefore guide prospecting and identify potential zones of hydrothermal fluid circulation.

关键词： Nassara calc-Alkaline Lamprophyre Metasomatic Activity LILE HREE LREE

Chemical and Sr-Nd compositions and ^(40)Ar/^(39)Ar ages of NW-trending dolerite dikes of Burkina Faso: Evidence for a Mesoproterozoic magmatism in the West African Craton

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Geoscience Frontiers 2018年第6期9卷 1957-1980页

作者： Boukare Tapsoba Ching-Hua lo Urbain Wenmenga Yoshiyuki Iizuka Sun-Lin Chung Gregory Shellnutt Department of Geosciences National Taiwan University UFR-SVT Département de Géologie Université Pr.Joseph Ki-Zerbo de Ouagadougou Institute of Earth Sciences Academia Sinica Department of Earth Sciences National Taiwan Normal University

The Paleoproterozoic basement of the northeastern part of the Leo-Man craton is intruded by generally NW-trending dikes. These regional scale dikes extend over 1000 km in Burkina Faso, Mali and Niger. We present chemical and Sr-Nd isotope compositions, as well as 40 Ar/39 Ar ages of these dikes with the following strikes N98°-N112°, and N114°-N124° in NE Burkina Faso. Field relationships show that the dikes are posterior to all other rock types dated between 2.26 ga and 2.0 ga. Chemical data indicate that the dikes are continental flood basalts and composed of low-ti(tiO2 ≤ 2 wt.%) sub-alkaline basalts and andesites. They exhibit a minor negative Europium anomaly(0.86-0.99) and slightly fractionated REE patterns((La/Yb)_N= 2.5-9.1; Yb_N = 9.5-19.9). The ratios of Th/Ta(1.3-11.4) and Ce/Pb(5.2-58.5)suggest a varying crustal assimilation of the dike magmas during ascent in the continental crust for all studied samples. calculated P-T conditions indicate that the magma reached temperatures of 1285 ℃(calculated from olivine compositions) and pressures of 6.9 kbar(calculated for pyroxene minerals).calculated initial 87 Sr/86 Sr(0.70040-0.70260) and ε_(Nd)(t)=+2.1 to-3.5 at 1575 Ma,also point to a crustal contamination with the most primitive samples showing T_(DM) values of 1946 Ma and 2154 Ma. The low values of La/Ba(low Th/Nb(tion-modified mantle as possible source for the dikes. Sr-Nd data, Mg# and NbTa-Zr-Y-Th-Tb-Yb compositions further suggest that the most primitive samples were emplaced in a none orogenic setting and their magmas were subjected to variable crustal contaminations. Literature and the present whole rock 40 Ar/39 Ar age determinations show that the dikes were emplaced during a widespread Mesoproterozoic magmatism between 1.6 ga and 1.2 ga, and were affected by a thermal event causing the argon systematics resetting, best constrained by the date of sample KK1(1236 ± 20 Ma,^(40)Ar/^(36)Ar = 294 ±13, MSWD = 2.2)

关键词： Mafic dike swarm Depleted mantle Mesoproterozoic Continental tholeiites Nuna West African Craton

Geochemical Characteristics and New Eruption Ages of Ruby-Related Basalts from Southeast Kenya

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Journal of Earth Science 2014年第5期25卷 799-821页

作者： Tawatchai Chualaowanich Chakkaphan Sutthirat Visut Pisuttha-Arnond Christoph Hauzenberger Chinghua lo Tongyi Lee Punya Charusiri Department of Geology Chulalongkorn University Patumwan Department of Mineral Resources Rama VI Rd. Ratchathewi Department of Earth Sciences Karlz-Fan University of Graz Department of Geoscience National Taiwan University Department of Earth Science National Taiwan Normal University

Two ruby-related basaltic fields were recently discovered in the southeast region of Kenya, exposed in the Nguu and Ngulai Hills vicinities. These fields host abundant deep-seated xenoliths, including corundum-bearing granulites. The basalts are alkaline affinity having compositions from foidrite to basanite. The Ngulai basalts have a wider range of SiO2（38.2 wt.%-44.8 wt.%） covering those of the Nguu basalts（38.7 wt.%-42.3 wt.%）. This overlapping behavior also holds for other major oxides and trace elements, e.g., Al2O3, Na2 O, K2 O, Cr, Ni, Rb and ga. The overall OIB-like incompatible patterns with strong K depletion and slight spike of ti enrichment signatures imply low degrees of partial melting of the upper mantle region source induced under a mantle plume-related process. The K-depletion signature indicates a residual K-bearing phase still retained in the source domain. Chondrite-normalized REE patterns exhibiting strong LREE enrichment without Eu anomalies suggest that plagioclase fractionation is insignificant. New 40Ar/39 Ar ages indicate eruption events occurred during the Pleistocene times, which are around 2 Ma for the Ngulai basalts and 0.9 to 1.6 Ma for the Nguu basalts. Clinopyroxene-basalt thermobarometric calculations yield the equilibrium P-T ranges of -8-29 kbar and 1 200-1 450 ℃.

关键词： ruby-related Cenozoic basalt Ar/Ar age corundum-bearing xenolith Kenya Nguu,Ngulai.

高厚度n型β-ga_(2)O_(3)薄膜的MOCVD制备

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发光学报 2022年第4期43卷 545-551页

作者：李政达焦腾董鑫刁肇悌陈威吉林大学电子科学与工程学院集成光电子学国家重点联合实验室吉林长春130012

高厚度的ga_(2)O_(3)薄膜能够提高器件的击穿电压,这种高厚度ga_(2)O_(3)薄膜往往是通过HVPE法制备的。然而HVPE法存在着成本高、设备少等缺点。本文通过金属有机化学气相沉积(MOCVD)工艺,以SiH_(4)为n型掺杂源,在ga_(2)O_(3)衬底上生... 详细信息

高厚度的ga_(2)O_(3)薄膜能够提高器件的击穿电压,这种高厚度ga_(2)O_(3)薄膜往往是通过HVPE法制备的。然而HVPE法存在着成本高、设备少等缺点。本文通过金属有机化学气相沉积(MOCVD)工艺,以SiH_(4)为n型掺杂源,在ga_(2)O_(3)衬底上生长了高厚度的n型β-ga_(2)O_(3)薄膜,并且研究了SiH_(4)流量对β-ga_(2)O_(3)性质的影响。实验中制备的β-ga_(2)O_(3)薄膜厚度达到4.15μm。薄膜的晶体质量高,表面致密光滑且呈现台阶流生长模式。随着SiH_(4)流量增加,晶体质量逐渐降低,电子浓度显著增加,电子迁移率降低。目前,高厚度β-ga_(2)O_(3)薄膜的电子浓度可以在3.6×10^(16)~5.3×10^(18) cm^(-3)范围内调控;当薄膜电子浓度为3.6×10^(16) cm^(-3)时,其电子迁移率可达137 cm^(2)·V^(-1)·s^(-1)。本文论证了MOCVD工艺进行高厚度n型β-ga_(2)O_(3)薄膜生长的可行性,这也为β-ga_(2)O_(3)基垂直结构功率器件的制备提供了一种新途径。

关键词：氧化镓金属有机化学气相沉积(MOCVD) 高厚度薄膜

Bioinformatics and Expression Analysis of NAC Transcription Factor Genes in Scutellaria baicalensis

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World Journal of Traditional Chinese Medicine 2018年第2期4卷 37-42页

作者： Juan Liu ti-Ying Chen Yuan Yuan Jun-Hui Zhou Yu-Yang Zhao Lu-Qi Huang Department in Chinese Academy of Chinese Medical Sciences State Key Laboratory Breeding Base of Dao-di HerbsChinese Academy of Chinese Medical Sciences

Background:NAC,as a unique transcription factor to plants,plays important roles in multiple biological functions,such as regulation of plant growth and development,hormone levels,and responses to various kinds of stresses.However,there is a lack of research of NAC genes in Chinese herbs.Objective:The study aimed to evaluate the potential functions of NAC genes in Scutellaria baicalensis by bioinformatics and expression analysis,and provide evidence of the molecular regulation mechanism involved in flavonoid biosynthesis in S.baicalensis.Methods:The genes of NAC transcription factors in S.baicalensis were obtained from cDNA library and their functions were explored using bioinformatic methods.The NAC genes were screened from the cDNA library of S.baicalensis using BLAST comparison software.Then,the open reading frame(ORF) finder online tool was used to predict the full-length ORFs of NAC genes and their protein characteristics were explored by bioinformatic methods.The expression of NAC genes was then detected by quantitative polymerase chain reaction in different parts of S.baicalensis and different leaves treated by gibberellin ga3 treatment.Results:Six genes of NAC transcription factors were cloned,two of which had complete ORFs.NAC genes cloned in this study were mainly expressed in the flowers of S.baicalensis.The expression levels of NAC2,NAC3,NAC4,NAC5,NAC6 were increased firstly and then decreased gradually after 100 μM ga3 treatment.Meanwhile,some NACs and PAL2 in S.baicalensis showed strong correlation.Conclusion:This study suggested that NACs cloned in this study were mainly regulated the flavonoid biosynthesis in the flowers of S.baicalensis;NAC6 in S.baicalensis might be involved in the regulation of PAL2 transcription and affected the accumulation of flavonoids in the root of S.baicalensis.Our results provided a basis for further understanding the molecular regulation mechanism of flavonoid biosynthesis in S.baicalensis.

关键词： Bioinformatics expression analysis NAC transcription factors Scutellaria baicalensis