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contribution to the understanding of the performance differences between commercial current collectors in Li–S batteries

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Journal of Energy chemistry 2021年第11期30卷 295-306,I0007页

作者： A.Benitez F.Luna-Lama Acaballero E.rodriguez-castellon J.Morales Dpto.Química Inorgánica e Ingeniería Química Instituto Universitario de Nanoquímica(IUNAN)Universidad de Córdoba14071 CórdobaSpain Dpto.de Química Inorgánica Cristalografía y MineralogíaFacultad de CienciasUniversidad de Málaga29071 MálagaSpain

Lithium–sulfur batteries have been recognised as highly promising next-generation batteries, due to their low cost and high theoretical energy density. Despite numerous advances in this technology over the last decade, its commercialisation is still a challenge that has not yet been achieved. Many efforts have been made to improve the problems that these batteries present, mainly by investigating different cathode manufacturing strategies, testing novel Li anodes, new additives in the electrolytes, and modified separators or interlayers. However, the characteristics of the current collectors used in the preparation of the electrodes have been rarely addressed. Three commercial collectors are commonly used in basic research on Li–S batteries: Al foil, carbon coated Al foil (Al-c), and carbon paper (gas diffusion layer, GDL). In this work, a detailed study of the electrochemical response of these commercial collectors has been carried out. The tests were carried out on two S composites formed by carbons of a different natures, commercial carbon black and synthetic N-doped graphene. In addition, the S impregnation method was different, using either melt diffusion at 155 ℃ or ethylenediamine as S solvent, respectively. In both systems, the results were similar – the electrodes supported on GDL delivered higher specific capacities than those supported on Al and Al-c, with minimal differences between the two. Of the different collector properties examined to explain this behaviour, namely Al corrosion, electrical conductivities, surface-level composition, and surface texture, only the latter had a significant effect in the performance of GDL-based electrodes. SEM images revealed a rough and cracked surface formed by the agglomerated carbon particles that give rise to a complex pore system, predominantly consisting of macropores. All of these features are beneficial for a better anchoring of the active material on the collector surface, in addition to enhancing the wettabi

关键词： current collector carbon paper Aluminum foil Lithium–sulfur battery

Million-scale data integrated deep neural network for phonon properties of heuslers spanning the periodic table

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npj computational Materials 2023年第1期9卷 2155-2166页

作者： Alejandro rodriguez changpeng Lin Hongao Yang Mohammed Al-Fahdi chen Shen Kamal choudhary Yong Zhao Jianjun Hu Bingyang cao Hongbin Zhang Ming Hu Department of Mechanical Engineering University of South CarolinaColumbiaSC 29208USA Theory and Simulation of Materials(THEOS) École Polytechnique Fédérale de LausanneCH-1015 LausanneSwitzerland Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China Institute of Materials Science Technical University of DarmstadtDarmstadt 64287Germany Materials Science and Engineering Division National Institute of Standards and TechnologyGaithersburgMD 20899USA Department of computer Science and Engineering University of South CarolinaColumbiaSC 29208USA

Existing machine learning potentials for predicting phonon properties of crystals are typically limited on a material-to-materialbasis, primarily due to the exponential scaling of model complexity with the number of atomic species. We address this bottleneckwith the developed Elemental Spatial Density Neural Network Force Field, namely Elemental-SDNNFF. The effectiveness andprecision of our Elemental-SDNNFF approach are demonstrated on 11,866 full, half, and quaternary Heusler structures spanning 55elements in the periodic table by prediction of complete phonon properties. Self-improvement schemes including active learningand data augmentation techniques provide an abundant 9.4 million atomic data for training. Deep insight into predicted ultralowlattice thermal conductivity (ctures is gained by p–d orbital hybridization analysis. Additionally, aclass of two-band charge-2 Weyl points, referred to as “double Weyl points”, are found in 68% and 87% of 1662 half and 1550quaternary Heuslers, respectively.

关键词： properties phonon spanning

Assessment of Genetic Stability Among In Vitro Plants of Arachis retusa Using RAPD and AFLP Markers for Germplasm Preservation

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Journal of Integrative Plant Biology 2007年第3期49卷 307-312页

作者： rachel Fatima Gagliardi Luiz Ricardo Hanai Georgia Pacheco carlos Alberto Oliveira Leonardo Alves carneiro José Francisco Montenegro Valls Elisabeth Mansur Maria Lucia carneiro Vieira Laboratório de Micropropagacao e Transformacao de Plantas Universidade do Estado do Rio de Janeiro postal code 20550-013 Maracana Rio de Janeiro Brazil Departamento de Genética - Escola Superior de Agricultura Luiz de Queiroz Universidade de Sao Paulo postal code 13418-900 Piracicaba Brazil Embrapa Recursos Genéticos e Biotecnologia postal code 70770-901 Brasilia Brazil

Arachis retusa Krapov. et W. c. Gregory et Valls is endemic in the West-central region of Brazil, occurring In areas endangered by human actions. The establishment of in vitro preservation methods for wild species of Arachis is an alternative to seed banks for germplasm storage, multiplication and distribution. The risk of genetic changes Induced by tissue culture and the monitoring of the genetic stability of the biological material before, during and after storage must be considered In the context of conservation. Random amplified polymorphlc ONA （RAPO） and amplified fragment length polymorphism （AFLP） fingerprinting were used to evaluate the genetic stability of in vitro plants originated from cotyledons and embryo axes of A. retusa. cotyledons originated shoots through direct organogenesls and embryo axes displayed muItishoot formation Induced by 110 mmol/L and 8.8 mmol/L BAP, respectively. Ninety genomlc regions （loci） generated from RAPO and 372 from AFLP analyses were evaluated. All amplified fragments detected by both techniques in plants derived from the two explant types were monomorphic. The results Indicate that the recovered shoots are genetically stable at the assessed genomic regions.

关键词： amplified fragment length polymorphism Arachis retusa in vitro preservation micropropagation random amplifiedpolymorphic DNA somaclonal variation

Use of wastes from the tea and coffee industries for the production of cellulases using fungi isolated from the Western Ghats of India

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Systems Microbiology and Biomanufacturing 2021年第1期1卷 33-41页

作者： S.A.Saldana-Mendoza J.A.Ascacio-Valdes A.S.Palacios-Ponce J.c.contreras-Esquivel R.rodriguez-Herrera H.A.Ruiz J.L.Martinez-Hernandez S.Sugathan c.N.Aguilar Bioprocesses and Bioproducts Research Group Food Research DepartmentAutonomous University of Coahuila25280 SaltilloMexico Faculty of Engineering in Mechanics and Production Sciences Polytechnic School of LitoralESPOLCampus Gustavo Galindo Km.30.5 Vía PerimetralP.O.Box 09-01-5863GuayaquilEcuador Microbiology Division Jawaharial Nehru Botanical Garden and Research InstitutePalodeThiruvananthapuramKerala 695562India

In this study,coffee pulp(coffea arabica)and green tea(camellia sinensis)residues were characterized for use as a substrate of solid-state fermentation for cellulases *** invasion rate was evaluated,as well as cellulases production by strains of Aspergillus niger and Trichoderma asperellum from the western Ghats of India,on coffee pulp,green tea,and a mixture of both substrates(50:50).***(AFP)strain was found to have the highest growth rate(0.409±0.021 mm/h)using a mixture of both *** production of cellulases by *** was unsatisfactory due to the presence of polyphenols in the supports to which *** cellulases are more *** production of cellulases by *** was linked to the pH of the supports,favouring the use of T and *** was found that the extracts produced by ***(28A strain using a mixture substrate,28A,and 20A strains using only green tea as a substrate)presented the highest cellulase activities when evaluated using a plate technique producing degradation halos of 2.3±0.1 cm of *** 28A strain did not require mineral enrichment media for cellulase production using green tea residues as support of solid-state fermentation.

关键词： cellulases Fungal strains Solid-state fermentation Agroindustrial wastes coffee pulp Green tea

Effects of Pupil Diameter on Light Detection and Temporal Modulation

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Eye Science 2003年第3期19卷 137-141页

作者： rachel S Li Andrew W Siu Johnny c Liyu Elice c chan Department of Optometry and Radiography The Hong Kong Polytechnic University Kowloon Hong Kong SAR China Corresponding author. Andrew W Siu PhD. Department of Optometry and Radiography The Hong Kong Polytechnic University Kowloon HongKong SAR ChinaDepartment of Optometry and Radiography The Hong Kong Polytechnic University Kowloon Hong Kong SAR China Department of Optometry and Radiography The Hong Kong Polytechnic University Kowloon Hong Kong SAR China

Purpose: This study compared the effects of pupil variation on light detection and temporal modulation across the central visual ***:Light detection sensitivity (LDS) and low flickering frequency (6Hz) temporal modulation sensitivity (TMS) of 20 young subjects were measured from the central visual field of the right eyes using an automated perimeter (Medmont M600). The measurements were taken under 3 artificial pupils, I.e. 3 mm, 4.3 mm and 6 mm *** sensitivities were grouped and averaged for different retinal eccentricities(3°, 6°, 10° and 15°).Results:TMS and LDS were reduced with increasing retinal eccentricities( P ＜ 0.001)and decreasing pupil diameters( P ＜ 0.001). TMS collected from all pupil diameters were significantly different from each other( P ＜ 0.001). Similarly, LDS under 3 mm pupil was statistically different from those of 4.3 mm and 6 mm(P ＜ 0.003). comparison of the hills of vision showed that pupil variation resulted in significantly different slopes (P=0.001).The slopes were also found to be significantly different between TMS and LDS (P=0.012).conclusions: The data showed that dilated pupil resulted in significantly higher sensitivities than those of smaller pupil for both visual functions. The difference in the slopes of hills of vision also suggested that the variation in retinal illumination affected the visual responses differently at various retinal eccentricitities for TMS and LDS.

关键词：瞳孔直径光觉检查中央视野闪烁频率

Pathogenesis of occult chronic hepatitis B virus infection

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World Journal of Gastroenterology 2011年第12期17卷 1543-1548页

作者： Rocio Aller de la Fuente María L Gutiérrez Javier Garcia-Samaniego conrado Fernández-rodriguez Jose Luis Lledó Gregorio castellano Gastroenterology Hospital Clinico Universitario Valladolid Institute of endocrinology and Nutrition Medical SchoolUniversity of Valladolid47003 ValladolidSpain Service of Gastroenterology Hospital Universitario Fundación AlcorcónAv Budapest-128922 AlcorcónMadridSpain Gastroenterology Department Hospital Carlos IIIc/Sinesio Delgado28029 MadridSpain Hospital Universitario 12 de Octubre Av de Andalucia 2804128039 MadridSpain

Occult hepatitis B infection(OBI) is characterized by hepatitis B virus(HBV) DNA in serum in the absence of hepatitis B surface antigen(HBsAg) presenting HBsAg-negative and anti-HBc positive serological *** HBV status is associated in some cases with mutant viruses undetectable by HBsAg assays;but more frequently it is due to a strong suppression of viral replication and gene *** is an entity with world-wide *** failure to detect HBsAg,despite the persistence of the viral DNA,is due in most cases to the strong suppression of viral replication and gene expression that characterizes this"occult"HBV infection;although the mechanisms responsible for suppression of HBV are not well *** majority of OBI cases are secondary to overt HBV infection and represent a residual low viremia level suppressed by a strong immune response together with histological derangements which occurred during acute or chronic HBV *** evidence suggests that it can favour the progression of liver fibrosis and the development of hepatocellular carcinoma.

关键词： Occult hepatitis B virus infection Hepatitis B virus-DNA Anti-HBc alone Hepatitis B virus Hepadnaviral hepatitis Occult viral persistence Primary occult infection Secondary occult infection Virus reactivation

Gastrointestinal disorders associated with migraine: A comprehensive review

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World Journal of Gastroenterology 2016年第36期22卷 8149-8160页

作者： carlos R cámara-Lemarroy Rene rodriguez-Gutierrez Roberto Monreal-Robles Alejandro Marfil-Rivera Servicio de Neurología Hospital Universitario "Dr. José E. González" Universidad Autónoma de Nuevo León Servicio de Endocrinología Hospital Universitario "Dr. José E. González" Universidad Autónoma de Nuevo León Servicio de Gastroenterología Hospital Universitario "Dr. José E. González" Universidad Autónoma de Nuevo León

Migraine is a recurrent and commonly disabling primary headache disorder that affects over 17% of women and 5%-8% of men. Migraine susceptibility is multifactorial with genetic, hormonal and environmental factors all playing an important role. The physiopathology of migraine is complex and still not fully understood. Many different neuropeptides, neurotransmitters and brain pathways have been implicated. In connection with the myriad mechanisms and pathways implicated in migraine, a variety of multisystemic comorbidities(e.g., cardiovascular, psychiatric and other neurological conditions) have been found to be closely associated with migraine. Recent reports demonstrate an increased frequency of gastrointestinal(GI) disorders in patients with migraine compared with the general population. Helicobacter pylori infection, irritable bowel syndrome, gastroparesis, hepatobiliary disorders, celiac disease and alterations in the microbiota have been linked to the occurrence of migraine. Several mechanisms involving the gut-brain axis, such as a chronic inflammatory response with inflammatory and vasoactive mediators passing to the circulatory system, intestinal microbiota modulation of the enteric immunological milieu and dysfunction of the autonomic and enteric nervous system, have been postulated to explain these associations. However, the precise mechanisms and pathways related to the gut-brain axis in migraine need to be fully elucidated. In this review, we survey the available literature linking migraine with GI disorders. We discuss the possible physiopathological mechanisms, and clinical implications as well as several future areas of interest for research.

关键词： Migraine Headache Microbiota Review Gastrointestinal diseases

Acetosolv delignification of marabou (Dichrostachys cinerea) wood with and without acid prehydrolysis

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Forestry Studies in china 2011年第1期13卷 64-70页

作者： Venkata Prabhakar SOUDHAM Dani rodriguez George J M ROcHA Mohammad J TAHERZADEH carlos MARTIN Bioresource Technology Group Department of Chemistry and Chemical EngineeringUniversity of Matanzas School of Engineering University of Bors Department of Biotechnology Lorena School of EngineeringUniversity of So Paulo

The chemical composition of marabou（Dichrostachys cinerea） wood and its treatment with acetic acid were *** different treatment approaches,direct acetosolv and combined acid prehydrolysis/acetosolv,were *** effects of acetic acid concentration（50%,70% and 90%） and temperature（normal boiling temperature and 121°c） on yield of solids,solubilization of lignin and hemicelluloses and recovery of cellulose were evaluated for both *** solubilization of marabou components was observed in the direct acetosolv treatment at 121°c,especially at the highest acetic acid concentration,where around 84.8% of lignin and 78% of hemicelluloses were *** the material was subjected to acid prehydrolysis prior to acetosolv treatment,lignin solubilization was improved,especially at low acetic acid *** 80% of the solubilized lignin was recovered from the liquors in the direct acetosolv treatment,but the recovery was lower in the combined *** was well preserved in all the treatment schemes.

关键词： Dichrostachys cinerea delignification acetosolv acid hydrolysis

Land cover change and carbon stores in a tropical montane cloud forest in the Sierra Madre Oriental,Mexico

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Journal of Mountain Science 2018年第10期15卷 2136-2147页

作者： Edgar G.LEIJA-LOREDO Numa P.PAVóN Arturo SáNcHEZ-GONZáLEZ Rodrigo rodriguez-LAGUNA GregorioáNGELES-PéREZ center for Biological Research Autonomous University of Hidalgo.42184 HidalgoMexico Institute oJ:Ag ricultural Sciences Academic Area of Forestry EngineeringAutonomous University of Hidalgo.43600 HidalgoMexico Postgraduate School Campus MontecilloPostgraduate in Forest Sciences.56230 Estado de MexicoMexico

Tropical montane cloud forest is one of the ecosystems with the highest biomass worldwide, representing an important carbon store. Globally its deforestation index is –1.1%, but in Mexico it is higher than –3%. carbon estimates are scarce globally, particularly in Mexico. The objective of this study was to simulate future land-cover scenarios for the Sierra Madre Oriental in Mexico, by analyzing past forest cover changes. Another objective was to estimate stored carbon in the two study areas. These objectives involve the generation of information that could be useful inputs to anti-deforestation public policy such as the REDD+ strategy. Remote sensing was used to measure land cover change and estimate carbon stocks. Satellite images from 2015, 2000 and 1986 were used, and Dinamica EGO freeware generatedmodels of future projections. Between 1986 and 2015, 5171 ha of forest were converted to pasture. The annual deforestation rates were –1.5% for Tlanchinol and –1.3% for the San Bartolo Tutotepec sites. Distance to roads and marginalization were highly correlated with deforestation. By 2030, an estimated 3608 ha of forest in these sites will have been converted to pasture. Stored carbon was estimated at 16.35 Mg c ha-1 for the Tlanchinol site and 12.7 Mg c ha-1 for the San Bartolo site. In the Sierra Madre Oriental deforestation due to land cover change(–1.4%) is higher than levels reported worldwide. Besides having high values of stored carbon(14.5 Mg c ha-1), these forests have high biodiversity. The models' outputs show that the deforestation process will continue if action is not taken to avoid the expansion of livestock pasturing. This can be done by paying incentives for forest conservation to the owners of the land. The results suggest that REDD+ is currently the most viable strategy for reducing deforestation rates in tropical montane cloud forests in Sierra Madre Oriental.

关键词： cloud forest carbon stores c mitigation climate change Dinamica EGO Forest management Remote sensing.