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<i>D’addio</i>to Blackness
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作者 Jose L. Parra 《International Journal of Astronomy and Astrophysics》 2021年第4期509-516,共8页
It is assumed here that the energy of a strong gravitational field creates non-linear effects over enclosed masses. This idea and the rigorous rules of the General Theory of Relativity output a metric that covers stro... It is assumed here that the energy of a strong gravitational field creates non-linear effects over enclosed masses. This idea and the rigorous rules of the General Theory of Relativity output a metric that covers strong and weak gravitational fields. The proposed metric could be correct because it included the Schwarzschild’s metric as a particular case and has no singularities. Additionally, it appears here that the massive condition of the gravitational fields has properties like the so-called Dark Matter. 展开更多
关键词 Black Holes Event Horizon Schwarzschild Metric Singularity General Theory of Relativity Dark Matter Neutron Stars
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Effects of cerium oxide doping on performance characteristics of nickel-based black coatings
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作者 QIN Zizhou CHEN Liyang +5 位作者 YANG Yumeng MAO Xifeng ZHU Benfeng GUO Weirong WEI Guoying ZHANG Luhan 《电镀与精饰》 北大核心 2026年第1期25-38,共14页
Black nickel coatings have emerged as a research hotspot in materials science due to their excellent performance and broad application prospects.In this study,nickel-based black coatings were fabricated on low-carbon ... Black nickel coatings have emerged as a research hotspot in materials science due to their excellent performance and broad application prospects.In this study,nickel-based black coatings were fabricated on low-carbon steel substrates via photo-assisted electrodeposition.A systematic investigation was conducted on the effects of cerium ion concentration and nano-ceria(CeO_(2))particle content in the electrolyte on the coating properties,along with an analysis of the temporal evolution of coating’s corrosion resistance.When the cerium ion concentration in the electrolyte was 0.05 mol/L,the coating exhibited a uniform black appearance with a light absorption rate of 95%,an emissivity of 0.87,maximum impedance,and the lowest corrosion tendency,demonstrating optimal comprehensive performance.The coating prepared with a nano-ceria concentration of 6 g/L in the electrolyte exhibited an emissivity of 0.9,achieved a 5B adhesion grade(ASTM D3359-09),and demonstrated a one-order-of-magnitude reduction in corrosion current density compared to coatings fabricated without nano-ceria in the electrolyte.With prolonged storage time,the coating's impedance slightly increased,leading to improved corrosion resistance. 展开更多
关键词 nickel-based coatings black coatings Ce oxide protective properties
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Turning Black Waste into a Green Resource
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作者 LIU JING 《China Today》 2026年第1期68-70,共3页
To deal with a polluted by-product of coal production,central China’s Shanxi Province has explored a governance path that addresses both the symptoms and root causes.
关键词 black waste green resource polluted product shanxi province coal production governance path
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VIIRS夜光影像中农田火像素识别方法
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作者 曹汉瑞 王妍 +3 位作者 李熙 胡申森 邱实 魏英策 《武汉大学学报(信息科学版)》 北大核心 2025年第10期2072-2085,共14页
夜光遥感影像已被广泛应用于人类活动、社会经济等方面的研究。南部非洲的夜光影像上存在烧田产生的农田火像素,这些像素易与城镇灯光像素混淆,干扰了夜光影像在社会经济评估中的应用。以南部非洲的10个大陆国家为研究区域,基于国家极... 夜光遥感影像已被广泛应用于人类活动、社会经济等方面的研究。南部非洲的夜光影像上存在烧田产生的农田火像素,这些像素易与城镇灯光像素混淆,干扰了夜光影像在社会经济评估中的应用。以南部非洲的10个大陆国家为研究区域,基于国家极地轨道伙伴关系卫星(national polar-orbiting partnership,NPP)/可见光红外成像辐射仪(visible infrared imaging radiometer,VIIRS)数据生产的黑色大理石(Black Marble)产品,首先构建了夜光辐亮度时间序列的3个特征;然后采用随机森林分类方法将夜光影像中的像素分为农田火像素、稳定灯光像素和全黑像素;最后采用分层随机抽样,用时间序列夜光辐亮度数据、高分辨率卫星影像和地表覆盖数据对像素分类结果进行精度检验。结果表明,像素分类的总体精度为91.2%,平均生产者精度为91.9%,平均用户精度为91.0%,其中农田火像素分类的生产者精度和用户精度分别为86.4%和92.6%。所提方法可在后续应用中滤除Black Marble产品中的农田火像素,提升夜光影像对非洲社会经济的评估精度。 展开更多
关键词 夜光遥感 NPP/VIIRS Black Marble产品 南部非洲 农田火
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Designing sandwich-structured IBP nanosheets with superior antioxidant property to enhance corrosion resistance,flame retardancy,and wear resistance for polymeric coatings 被引量:1
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作者 Qihan Weng Li Zhang +1 位作者 Xinxin Sheng Delong Xie 《Journal of Materials Science & Technology》 2025年第12期22-35,共14页
The rapid development of industrialization requires the advancement of multifunctional coatings.In this study,successful self-assembly of iron porphyrin on BP nanosheets resulted in the synthesis of IBP nanosheets wit... The rapid development of industrialization requires the advancement of multifunctional coatings.In this study,successful self-assembly of iron porphyrin on BP nanosheets resulted in the synthesis of IBP nanosheets with a sandwich structure.Characterization tests including SEM,XPS,SPM,and XRD confirmed the successful preparation of IBP nanosheets with robust structural stability and antioxidation.Subsequently,a water-based epoxy resin(WEP)coating containing IBP nanosheets was prepared.Test results revealed that the composite coating containing 0.4 wt.%IBP nanosheets exhibited outstanding anti-corrosion,wear-resistant,and flame-retardant properties.After 42 days of immersion in a 3.5 wt.%NaCl solution,the Rct value of the 4-IBP/WEP coating was 1.79×10^(9)Ωcm^(2),surpassing the Pure WEP coating by more than 3 orders of magnitude.Additionally,the peak heat release rate(PHRR)and wear rate of the 4-IBP/WEP coating decreased by 19.29%and 90.97%compared to the Pure WEP coating.This research presents a novel idea for the utilization of BP nanosheets in multifunctional coatings. 展开更多
关键词 Black phosphorus Corrosion resistance WEAR-RESISTANT FLAME-RETARDANT
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Weathering Process of Parent Material and Accumulation Process of Organic Carbon on the Black Soil Profile:A Case Study from the Keshan Area of the Songnen Plain in Northeast China 被引量:1
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作者 XIA Rui YUAN Guoli +5 位作者 CUI Minli HOU Hongxing YU Guangming GE Liangsheng LU Kaining REN Bingzhang 《Acta Geologica Sinica(English Edition)》 2025年第1期258-271,共14页
Black soil is essential for maintaining regional food security and promoting global agricultural production.Understanding the weathering process of parent material and the accumulation of organic carbon is crucial to ... Black soil is essential for maintaining regional food security and promoting global agricultural production.Understanding the weathering process of parent material and the accumulation of organic carbon is crucial to comprehending the developmental history and future trends of black soil,especially against the background of large-scale global cultivation and climate change.Although the importance of black soil formation and evolution cannot be ignored,the relevant research is still very scarce.In this study,a typical eight-meter-deep soil core was collected from the Keshan area of the Songnen Plain,Northeast China,where surface black soil developed on paleo-sediments.Using^(14)C dating,the formation age of the black soil was determined.Based on the characteristics of the geochemical composition,grain size and the magnetic susceptibility of the sediments,it was demonstrated that the black soil and its parent material originated from reworked loess.Furthermore,the mass transfer coefficient(τ)of some elements was determined,in order to explore the soil weathering process.By calculating the transported amount of alkaline and alkaline-earth elements,the weathering rate of parent material to black soil was found to be weak,at 0.16 kEq·ha^(-1)·year^(-1).Combining the results of dating and carbon density in the different layers of black soil,the accumulation rate of organic carbon was determined as follows:rapidly increasing in the initial period of 13.2-2.2 ka,reaching its maximum average value of 34.0 g·cm^(-2)·a^(-1)at 2.2-0.8 ka,then showing a decreasing trend with an average value of-77.5 g·cm^(-2)·a^(-1).Compared with regional climate change,Keshan black soil has developed under a colder and wetter climate during the Holocene.Predictably,ongoing global warming may lead to the degradation of black soils in the Songnen Plain,as well as in other regions.Our results will enrich geological knowledge of black soil formation and future evolutionary trends. 展开更多
关键词 black soil PROVENANCE weathering rate organic carbon accumulation rate Songnen Plain
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Newly Identified Au-Ag-Bi-Te Mineralization in the Aydindere Skarn Fe and Cu Deposit,Giresun,NE Turkey:Implications of Gold Mineralization during Retrograde Skarn Evolution 被引量:1
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作者 Ahmet Sasmaz Vitaliy Sukach +7 位作者 Serhiy Bondarenko Hryhorii Aleksiienko Hengameh Erfanian Kaseb Bilge Sasmaz Sergiy Kurylo Oleksandr Hrinchenko Volodymyr Somka Panagiotis Voudouris 《Journal of Earth Science》 2025年第2期543-561,共19页
This study investigates the mineralogy and mineral-chemistry of a newly discovered Au-Ag-Bi-Te mineralization at the Aydindere Fe-Cu skarn deposit,within the Pontides Tectonic Unit,northeastern Turkey.The mineralizati... This study investigates the mineralogy and mineral-chemistry of a newly discovered Au-Ag-Bi-Te mineralization at the Aydindere Fe-Cu skarn deposit,within the Pontides Tectonic Unit,northeastern Turkey.The mineralization is developed in the skarn zone at the contact between Upper Cretaceous andesite-pyroclastic rocks and a Paleocene–Eocene I-type granitoid.The principal ore minerals of the Aydindere Fe-Cu deposit are oxides(magnetite),sulfides(pyrite-chalcopyritegalena-sphalerite),tellurides/sulfotellurides(tetradymite,hessite),sulfosalts(wittichenite,emplectite,aikinite) and native gold-electrum.Skarn minerals include anhydrous phases(garnet) formed in a prograde stage and hydrous phases(amphibole,epidote,chlorite),which were formed in a retrograde stage in association with quartz,adularia,apatite and late calcite.Sulfides,tellurides and sulfosalts are introduced during the retrograde stage.The Au-Ag-Bi-Te mineralization was detected for the first time within the western ore body of the Aydindere deposit,and occurs in calcite-bearing sulfide bodies that cut magnetite-garnet-amphibole-epidote skarns with magnetite ores of different grade,including massive magnetite.Chlorite geothermometry indicates formation of the Au-Ag-BiTe mineralization at temperatures between 300 and 250 ℃,during the retrograde skarn evolution.Assuming the temperature is ~275 ℃,logfS_(2) =-10.5 to-13,logfO_(2) =-37 to-33,and logf Te2 values range from approximately-12 to-8.5 were estimated.The available mineralogical and geological data(presences of magnetite,oxidized-type tellurides/sulfotellurides,and andraditic garnets,and absence of pyrrhotite and arsenopyrite) suggest that Aydindere is an oxidized Au-bearing skarn deposit.The discovery of Au-Ag-Bi-Te mineralization at Aydindere increases its productivity and requires more detailed exploration in the deposit for precious(Au,Ag) and critical(Bi,Te) metals. 展开更多
关键词 aydindere Black Sea Region telluredes oxidized gold-bearing skarn deposit mineral geology
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A Comprehensive Review of Natural Rubber Composites:Properties,Compounding Aspects,and Renewable Practices with Natural Fibre Reinforcement 被引量:1
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作者 Mohamad Firdaus Omar Fathilah Ali +6 位作者 Mohammed Saedi Jami Azlin Suhaida Azmi Farah Ahmad Mohd Zahid Marzuki Shantha Kumari Muniyandi Zuraidah Zainudin Minsoo P.Kim 《Journal of Renewable Materials》 2025年第3期497-538,共42页
This review provides a comprehensive overview of natural rubber(NR)composites,focusing on their properties,compounding aspects,and renewable practices involving natural fibre reinforcement.The properties of NR are inf... This review provides a comprehensive overview of natural rubber(NR)composites,focusing on their properties,compounding aspects,and renewable practices involving natural fibre reinforcement.The properties of NR are influenced by the compounding process,which incorporates ingredients such as elastomers,vulcanizing agents,accelerators,activators,and fillers like carbon black and silica.While effective in enhancing properties,these fillers lack biodegradability,prompting the exploration of sustainable alternatives.The potential of natural fibres as renewable reinforcements in NR composites is thoroughly covered in this review,highlighting both their advan-tages,such as improved sustainability,and the challenges they present,such as compatibility with the rubber matrix.Surface treatment methods,including alkali and silane treatments,are also discussed as solutions to improve fibre-matrix adhesion and mitigate these challenges.Additionally,the review highlights the potential of oil palm empty fruit bunch(EFB)fibres as a natural fibre reinforcement.The abundance of EFB fibres and their alignment with sustainable practices make them promising substitutes for conventional fillers,contributing to valuable knowledge and supporting the broader move towards renewable reinforcement to improve sustain-ability without compromising the key properties of rubber composites. 展开更多
关键词 Natural rubber composites natural fibres RENEWABLE REINFORCEMENT VULCANIZATION FILLERS carbon black silica surface treatment sound absorption acoustics
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High-resolution Simulation Dataset of Hourly PM_(2.5)Chemical Composition in China(CAQRA-aerosol)from 2013 to 2020 被引量:1
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作者 Lei KONG Xiao TANG +14 位作者 Jiang ZHU Zifa WANG Bing LIU Yuanyuan ZHU Lili ZHU Duohong CHEN Ke HU Huangjian WU Qian WU Jin SHEN Yele SUN Zirui LIU Jinyuan XIN Dongsheng JI Mei ZHENG 《Advances in Atmospheric Sciences》 2025年第4期697-712,共16页
Scientific knowledge on the chemical compositions of fine particulate matter(PM_(2.5)) is essential for properly assessing its health and climate effects,and for decisionmakers to develop efficient mitigation strategi... Scientific knowledge on the chemical compositions of fine particulate matter(PM_(2.5)) is essential for properly assessing its health and climate effects,and for decisionmakers to develop efficient mitigation strategies.A high-resolution PM_(2.5) chemical composition dataset(CAQRA-aerosol)is developed in this study,which provides hourly maps of organic carbon,black carbon,ammonium,nitrate,and sulfate in China from 2013 to 2020 with a horizontal resolution of 15 km.This paper describes the method,access,and validation results of this dataset.It shows that CAQRA-aerosol has good consistency with observations and achieves higher or comparable accuracy with previous PM_(2.5) composition datasets.Based on CAQRA-aerosol,spatiotemporal changes of different PM_(2.5) compositions were investigated from a national viewpoint,which emphasizes different changes of nitrate from other compositions.The estimated annual rate of population-weighted concentrations of nitrate is 0.23μg m^(−3)yr^(−1) from 2015 to 2020,compared with−0.19 to−1.1μg m^(−3)yr^(−1) for other compositions.The whole dataset is freely available from the China Air Pollution Data Center(https://doi.org/10.12423/capdb_PKU.2023.DA). 展开更多
关键词 PM_(2.5)composition dataset black carbon organic carbon AMMONIUM NITRATE SULFATE
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GeP_(3)/Ketjen Black Composite:Preparation via Ball Milling and Performance as Anode Material for Sodium-ion Batteries
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作者 YANG Shuqi YANG Cunguo +2 位作者 NIU Huizhu SHI Weiyi SHU Kewei 《无机材料学报》 北大核心 2025年第3期329-336,I0010,I0011,共10页
Metal phosphides have been studied as prospective anode materials for sodium-ion batteries(SIBs)due to their higher specific capacity compared to other anode materials.However,rapid capacity decay and limited cycle li... Metal phosphides have been studied as prospective anode materials for sodium-ion batteries(SIBs)due to their higher specific capacity compared to other anode materials.However,rapid capacity decay and limited cycle life caused by volume expansion and low electrical conductivity of phosphides in SIBs remain still unsolved.To address these issues,GeP_(3) was first prepared by high-energy ball milling,and then Ketjen black(KB)was introduced to synthesize composite GeP_(3)/KB anode materials under controlled milling speed and time by a secondary ball milling process.During the ball milling process,GeP_(3) and KB form strong chemical bonds,resulting in a closely bonded composite.Consequently,the GeP_(3)/KB anodes was demonstrated excellent sodium storage performance,achieving a high reversible capacity of 933.41 mAh·g^(–1) at a current density of 0.05 A·g^(–1) for a special formula of GeP_(3)/KB-600-40 sample prepared at ball milling speed of 600 r/min for 40 h.Even at a high current density of 2 A·g^(–1) over 200 cycles,the capacity remains 314.52 mAh·g^(–1) with a retention rate of 66.6%.In conclusion,this work successfully prepares GeP_(3)/KB anode-carbon composite for electrodes by high-energy ball milling,which can restrict electrode volume expansion,enhance capacity,and improve cycle stability of SIBs. 展开更多
关键词 sodium-ion battery GeP_(3)/C composite Ketjen black ball milling
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Enhancing energy density in planar micro-supercapacitors:The role of few-layer graphite/carbon black/NiCo_(2)O_(4) composite materials
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作者 ZHANG Wanggang HUANG Lei +3 位作者 WANG Menghu WANG Jian WEI Aili LIU Yiming 《燃料化学学报(中英文)》 北大核心 2025年第5期646-662,共17页
The advancement of planar micro-supercapacitors(PMSCs)for micro-electromechanical systems(MEMS)has been significantly hindered by the challenge of achieving high energy and power densities.This study addresses this is... The advancement of planar micro-supercapacitors(PMSCs)for micro-electromechanical systems(MEMS)has been significantly hindered by the challenge of achieving high energy and power densities.This study addresses this issue by leveraging screen-printing technology to fabricate high-performance PMSCs using innovative composite ink.The ink,a synergistic blend of few-layer graphene(Gt),carbon black(CB),and NiCo_(2)O_(4),was meticulously mixed to form a conductive and robust coating that enhanced the capacitive performance of the PMSCs.The optimized ink formulation and printing process result in a micro-supercapacitor with an exceptional areal capacitance of 18.95 mF/cm^(2)and an areal energy density of 2.63μW·h/cm^(2)at a current density of 0.05 mA/cm^(2),along with an areal power density of 0.025 mW/cm^(2).The devices demonstrated impressive durability with a capacitance retention rate of 94.7%after a stringent 20000-cycle test,demonstrating their potential for long-term applications.Moreover,the PMSCs displayed excellent mechanical flexibility,with a capacitance decrease of only 3.43%after 5000 bending cycles,highlighting their suitability for flexible electronic devices.The ease of integrating these PMSCs into series and parallel configurations for customized power further underscores their practicality for integrated power supply solutions in various technologies. 展开更多
关键词 graphite/carbon black composite NiCo_(2)O_(4) screen printing planar micro-supercapacitor energy density mechanical flexibility
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Potential benefits of Nigella Sativa(black seeds)in the management of“Chandipura virus infection”–an insight
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作者 Naina Mohamed Pakkir Maideen 《Food and Health》 2025年第2期3-14,共12页
The Chandipura vesiculovirus(CHPV),a single-stranded,negative sense RNA arbovirus with five structural proteins-the G,N,M,P,and L proteins-is the source of Chandipura virus infection.Children between the ages of 9 mon... The Chandipura vesiculovirus(CHPV),a single-stranded,negative sense RNA arbovirus with five structural proteins-the G,N,M,P,and L proteins-is the source of Chandipura virus infection.Children between the ages of 9 months and 14 years old are the most common recipients of CHPV infection,which is primarily spread by sand flies(Sergentomyia,Phlebotomus species).The potential advantages of black seeds(N.sativa)in the treatment of patients with CHPV infection are the main topic of our current review.The majority of patients infected with CHPV experience neurological complications such as encephalitis and other neurological complications.Since there is currently no approved antiviral treatment,supportive care and symptomatic therapy are the primary methods used to manage CHPV-infected patients.Herbal candidates possessing antioxidant,immunomodulatory,antiviral,and anti-inflammatory qualities may aid in the treatment of CHPV infection.The antiviral,anti-inflammatory,antioxidant,and immunomodulatory qualities of black seeds(N.sativa)have been shown in a number of preclinical and clinical investigations;these attributes could be helpful in the treatment of CHPV infection.Black seeds(N.sativa)may help treat CHPV-infected patients in the early stages of their illness when used in conjunction with symptomatic therapy and supportive care.In patients infected with CHPV,additional randomized controlled clinical trials would assess the efficacy and safety of black seeds(N.sativa). 展开更多
关键词 Chandipura virus ENCEPHALITIS Nigella Sativa black seeds black cumin seeds THYMOQUINONE antiviral anti-inflammatory antioxidant IMMUNOMODULATORY
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There Is No Black American Identity and Community
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作者 Paul C.Mocombe 《Philosophy Study》 2025年第1期35-41,共7页
This work provides a descriptive analysis of the so-called Black American community whose practical consciousness is a result of adopting,and reacting to,both white values and discriminatory terms to constitute their ... This work provides a descriptive analysis of the so-called Black American community whose practical consciousness is a result of adopting,and reacting to,both white values and discriminatory terms to constitute their practical activities and so-called cultural identity.Outside of the practices associated with these values and discriminatory terms,there is no sui generis Black American identity and community with its own form of system and social integration that is different from,or diametrically opposes,the Protestant Ethic and the spirit of capitalism of their white counterparts,which would emerge out of that relationship. 展开更多
关键词 Black Church African-Americanization racial identity religiosity Black Diaspora SPIRITUALISM phenomenological structuralism
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Gram-scale synthesis of simple cubic phase black phosphorus via shock-induced phase transformation:Mechanistic insights and process-dependent phase control
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作者 Jinchao Qiao Qiang Zhou +9 位作者 Rufei Qiao Zhuwen Lyu Longhai Zhong Tianchu Wang Yan Liu Junbo Yan Fan Bai Xin Gao Pengwan Chen Peng Si 《Defence Technology(防务技术)》 2025年第11期293-308,共16页
Simple cubic black phosphorus(BP)has been recognized as a strategic material due to its exceptional structural stability under extreme conditions.In this investigation,simple cubic BP was successfully synthesized thro... Simple cubic black phosphorus(BP)has been recognized as a strategic material due to its exceptional structural stability under extreme conditions.In this investigation,simple cubic BP was successfully synthesized through shock-induced phase transformation,utilizing amorphous red phosphorus as the precursor material.The phase evolution process was systematically investigated using plane shock loading apparatus,with shock pressure and temperature parameters being precisely controlled to optimize transformation kinetics.Comprehensive phase characterization revealed the correlation between thermodynamic loading profiles and cubic BP formation efficiency.Precursor modification strategies were implemented through orthorhombic BP utilization,resulting in enhanced cubic phase yield and crystallinity.The synthesized cubic BP variants are considered promising candidates for advanced protective material systems,particularly where combinations of mechanical resilience and thermal stability are required under extreme operational conditions.This research provides critical insights into shock-induced phase transformation mechanics,while establishing foundational protocols for manufacturing non-equilibrium materials with potential applications in next-generation defensive technologies. 展开更多
关键词 Shock-induced phase transformation Orthorhombic black phosphorus Rhombohedral black phosphorus Simple cubic black phosphorus Shock-wave engineered materials Pressure-responsive polymorphs
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“He Yells at Me Three Times:Stay in Your Car!”:Rap Culture,Black Identity and Reception of the Message of Police Brutality in Quebec City
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作者 Marie Therese Atsena Abogo 《Sociology Study》 2025年第4期155-164,共10页
An earlier version of this paper has been presented online at the annual Conference of Canadian Sociological Association,during the Congress of Humanities and Social Sciences in Toronto in June 2025.It explores how ra... An earlier version of this paper has been presented online at the annual Conference of Canadian Sociological Association,during the Congress of Humanities and Social Sciences in Toronto in June 2025.It explores how rap music in Quebec,particularly through the work of the rap artist Webster and his collective Limoilou Starz(LS),serves as a tool for meaning-making,political expression,and resistance against racial profiling and police brutality experienced by Black youth in Quebec City.The study focuses on the song“SPVQ”(Service de police de la Ville de Québec)as a case study to analyze the encoding and reception of anti-racist messages within rap culture.Webster draws from a global tradition of socio-political rap-like that of African-American rappers KRS-One,LL Cool J,and Tupac-while anchoring his critique in the local realities of Limoilou,a marginalized,racially diverse district of Quebec City.Through a narrative,figurative,semantic,and ideological analysis of the song,the paper reveals how Webster articulates themes of police brutality,structural discrimination,economic marginalization,and resistance.The rapper’s message is both a form of testimony and a civic intervention.His broader activism is analyzed through ethnographic techniques-including participant observation and interviews during workshops,media appearances,and online campaigns.It translates these messages into tangible social practices.To explain the persistence of these injustices,the paper situates the issue within Quebec’s interculturalism framework,which ostensibly promotes dialogue and integration but often masks or even reinforces structural racism.This model maintains a symbolic majority/minority duality and conditions inclusion on conformity to a dominant White Francophone identity,thus rendering racialized youth as perpetual outsiders. 展开更多
关键词 hip-hop culture Black identity Black youth rap culture police brutality Quebec
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Primordial Black Holes Formed during Magneto-Hydrodynamic Turbulence in the Early Universe as Dominant Part of Dark Matter
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作者 Jia-Xiang Liang Peng Xu +1 位作者 Ming-Hui Du Zi-Ren Luo 《Chinese Physics Letters》 2025年第11期393-399,共7页
Primordial black holes(PBHs) offer a compelling candidate for dark matter. The production of PBHs through well-tested and accepted physical processes is highly worthy of investigation. This work highlights the role of... Primordial black holes(PBHs) offer a compelling candidate for dark matter. The production of PBHs through well-tested and accepted physical processes is highly worthy of investigation. This work highlights the role of turbulences in the very early universe in sustaining intense and persistent fluctuations in energy or mass density,which could provide a natural mechanism for PBH formation in the primordial universe. We analyze the mass range and abundance of PBHs produced in the magnetohydrodynamic turbulence induced by the electroweak phase transition. Remarkably, we find that the mass range of the produced PBHs falls within the most viable“asteroid mass” window from the present-day observations, and within natural parameter regions their abundance can be sufficiently large. These findings suggest that PBHs produced during magnetohydrodynamic turbulence in the very early universe may comprise a dominant part of dark matter. 展开更多
关键词 primordial universe primordial black holes pbhs electroweak phase transition primordial black holes mass range dark matter magnetohydrodynamic turbulence
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Iceland’s Diamond Beach
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作者 胡金莹 《疯狂英语(新读写)》 2025年第12期50-51,78,共3页
A black sand beach littered with huge chunks of glistening(闪亮的)ice has become one of the most visited attractions in Iceland,and for good reason,it looks like something out of a fantasy movie.Known as Breiðame... A black sand beach littered with huge chunks of glistening(闪亮的)ice has become one of the most visited attractions in Iceland,and for good reason,it looks like something out of a fantasy movie.Known as Breiðamerkursandur in Icelandic,Diamond Beach takes its name from the chunks of pristine ice scattered across the black volcanic sand and glistening like giant,uncut diamonds. 展开更多
关键词 fantasy movie black volcanic sand black sand beach Diamond Beach Brei amerkursandur chunks pristine pristine ice glistening ice
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Thermodynamic aspects of higher-dimensional black holes in Einstein-Gauss-Bonnet gravity through exponential entropy
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作者 Sana Malik Abdul Jawad +3 位作者 Shahid Chaudhary Mohammad Mahtab Alam Sanjar Shaymatov Shamaila Rani 《Communications in Theoretical Physics》 2025年第4期129-150,共22页
We assume exponential corrections to the entropy of 5D charged Ad S black hole solutions,which are derived within the framework of Einstein-Gauss-Bonnet gravity and nonlinear electrodynamics.Additionally,we consider t... We assume exponential corrections to the entropy of 5D charged Ad S black hole solutions,which are derived within the framework of Einstein-Gauss-Bonnet gravity and nonlinear electrodynamics.Additionally,we consider two distinct versions of 5D charged Ad S black holes by setting the parameters q→0 and k→0(where q represents the charge,and k is the non-linear parameter).We investigate these black holes in the extended phase space,where the cosmological constant is interpreted as pressure,demonstrating the first law of black hole thermodynamics.The focus extends to understanding the thermal stability or instability,as well as identifying first and second-order phase transitions.This exploration is carried out through the analysis of various thermodynamic quantities,including heat capacity at constant pressure,Gibbs free energy(GFE),Helmholtz free energy(HFE),and the trace of the Hessian matrix.In order to visualize phase transitions,identify critical points,analyze stability and provide comprehensive analysis,we have made the contour plot of the mentioned thermodynamic quantities and observed that our results are very consistent.These investigations are conducted within the context of exponentially corrected entropies,providing valuable insights into the intricate thermodynamic behavior of these 5D charged Ad S black holes under different parameter limits. 展开更多
关键词 black hole thermodynamics thermodynamics quantities thermal stability higher dimensional Einstein-Gauss-Bonnet black hole modified entropy
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Review of the current clinical and preclinical evidence pertaining to the immunomodulatory effects of black seeds (Nigella sativa)
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作者 Rajkapoor Balasubramanian Naina Mohamed Pakkir Maideen Arun Shanmugam 《Acupuncture and Herbal Medicine》 2025年第1期46-56,共11页
Humans and other vertebrates are safeguarded from invading pathogenic microbes by the immune system.Black seed,scientifically known as Nigella sativa,has garnered attention for its potential immunomodulatory effects i... Humans and other vertebrates are safeguarded from invading pathogenic microbes by the immune system.Black seed,scientifically known as Nigella sativa,has garnered attention for its potential immunomodulatory effects in both clinical and preclinical studies.This comprehensive review aims to consolidate and analyze the existing body of evidence surrounding the immunological impact of black seeds.In this review,we analyze the immunomodulatory potentials of black seeds(N.sativa).For the purpose of finding pertinent publications,the literatures was searched in web-based databases,including Web of Science,Medline/PMC/PubMed,Embase,EBSCO,Google Scholar,Science Direct,and reference lists.Several clinical,in vivo,and in vitro studies have demonstrated that supplementation with black seeds(N.sativa)has potential immunomodulatory activity.Black seeds(N.sativa)may influence immune responses through a variety of mechanisms.By synthesizing and critically assessing the current state of knowledge on the immunomodulatory effects of black seeds,this review aims to provide valuable insights into the potential therapeutic uses and future research directions for harnessing the immunological benefits of this natural remedy. 展开更多
关键词 Black seeds IMMUNOMODULATION IMMUNOSTIMULATION IMMUNOSUPPRESSION Interferon LYMPHOCYTES Nigella sativa
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Characterized Behaviors of Black Hole Thermodynamics in the Supercritical Region
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作者 Zi-Qiang Zhao Zhang-Yu Nie +1 位作者 Jing-Fei Zhang Xin Zhang 《Chinese Physics Letters》 2025年第10期331-335,共5页
The comprehension of universal thermodynamic behaviors in the supercritical region is crucial for examining the characteristics of black hole systems under high temperature and pressure.This study is devoted to the an... The comprehension of universal thermodynamic behaviors in the supercritical region is crucial for examining the characteristics of black hole systems under high temperature and pressure.This study is devoted to the analysis of characteristic lines and crossover behaviors within the supercritical region.By making use of the free energy,we introduce three key thermodynamic quantities:scaled variance,skewness,and kurtosis.Our results demonstrate that the Widom line,associated with the maximal scaled variance,can effectively differentiate between small and large black hole-like subphases,each displaying distinct thermodynamic behaviors within the supercritical region.Furthermore,by utilizing quasinormal modes,we identify the Frenkel line,offering a dynamic perspective to distinguish between small and large black hole-like subphases.These contribute to a deeper comprehension of black hole subphases in the supercritical region,thus illuminating new facets of black hole thermodynamics. 展开更多
关键词 scaled variance supercritical region widom lineassociated analysis characteristic lines crossover behaviors SKEWNESS comprehension universal thermodynamic behaviors examining characteristics black hole systems black hole thermodynamics
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