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S-scheme unidirectional transmission of CdS-CuO heterojunction benefits for superior photocatalytic hydrogen evolution efficiency
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作者 ZHAO Haiting YAN Zheng +2 位作者 LIU Yang JIANG Longde LUAN Jingde 《燃料化学学报(中英文)》 北大核心 2026年第1期1-14,共14页
The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor ... The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion. 展开更多
关键词 photocatalytic hydrogen evolution CdS-CuO S-scheme heterojunction electron directional transmission interfacial electric field DFT calculation
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The historical evolution of the Serbisütherapy in traditional Mongolian medicine,from its origins to contemporary practice
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作者 Mei-Ri Na Manda Manda +1 位作者 Temuqile Temuqile De-Zhi Yang 《History and Philosophy of Medicine》 2026年第1期43-48,共6页
Serbisütherapy(ST)is a distinctive external treatment modality within traditional Mongolian medicine(TMM),historically developed within a nomadic cultural framework.This study presents a comprehensive philologica... Serbisütherapy(ST)is a distinctive external treatment modality within traditional Mongolian medicine(TMM),historically developed within a nomadic cultural framework.This study presents a comprehensive philological and historical analysis of ST,tracing its evolution from early battlefield applications to contemporary clinical use.By critically examining classical Mongolian medical texts alongside modern case studies,we aim to systematize ST’s therapeutic methods,indications,and limitations,while exploring its mechanisms of action through both traditional theory and modern biomedical perspectives.ST has undergone significant transformation,shifting from whole-body cavity immersion in the 13th century to targeted,organ-specific applications in modern practice.Its four primary methods–Covering,Mounted,Organ Placement,and Suction–demonstrate efficacy in treating cold-natured diseases,musculoskeletal disorders,gynecological conditions,and certain emergencies.ST embodies the core principles of TMM,particularly the balance of the“Three Roots”and the correction of cold-induced pathologies through heat.Despite challenges related to standardization,cultural translation,and regulatory acceptance,ST holds translational potential for integrative medicine.Future research should prioritize mechanistic validation,clinical standardization,and the development of biocompatible thermal technologies to bridge traditional practice with modern healthcare systems. 展开更多
关键词 Serbisütherapy traditional Mongolian medicine THERMOTHERAPY historical evolution integrative medicine
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The Sedimentary System and Evolution of the Early Tertiary in the Sunda Basin, Indonesia 被引量:2
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作者 Zhong Dakang Zhu Xiaomin Zhang Qin 《Petroleum Science》 SCIE CAS CSCD 2006年第1期1-11,共11页
The Sunda basin is located at the north of the Sunda Strait situated between Sumatra and Java islands, Indonesia. It is an early Tertiary typical half-graben basin, in which developed a series of terrigenous clastic s... The Sunda basin is located at the north of the Sunda Strait situated between Sumatra and Java islands, Indonesia. It is an early Tertiary typical half-graben basin, in which developed a series of terrigenous clastic sedimentation. Previous work suggested that the early Tertiary sediments were alluvial, fluvial, lacustrine and swamp deposits, of which the Banuwati formation was alluvial and lacustrine deposits, the Zelda member fluvial deposits, and Gita member fluvial and swamp deposits. In this paper, based on the integrated research on core lithology (including lithology succession and structure), well log shape, and seismic reflection characteristics, a more detailed sedimentation system was set up as follows: l) In addition to the alluvial, lacustrine, fluvial and the swamp deposits presented in previous work, subaqeous fan, shore-shallow lacustrine, deep lacustrine and turbidite fan, fan delta and delta deposits also developed in this basin. 2) Alluvial fan, subaqeous fan and fan delta deposits occurred on the steep slope adjacent to the synrift boundary fault; while the deltaic depositional system usually distributed on the gentle slope of the basins. 3) The Zelda member that was interpreted as a fluvial deposit in previous work is now interpreted as a subaqueous fan, fan delta, delta and lacustrine deposit system. 4) From the point of view of sedimentology, the evolution of basin could be divided into four stages: the initial subsidence (matching the Banuwati formation), the rapid subsidence (matching the low Zelda member of Talang Akar formation), the steady subsidence or fluctuation (matching the middle Zelda member of Talang Akar formation), and the uplifting (matching the upper Zelda member and the Gita member of Talang Akar formation). At the initial subsidence stage, the alluvial fan, flood plain, braided stream deposits developed, and then subaqeous fan sedimentation; at the rapid subsidence stage, shore-shallow lacustrine and deep lacustrine deposits and turbidite fans occurred; at the steady subsidence stage, thick fan deltas and delta sandstones developed; and at the uplifting stage, came fluvial (including meandering fiver and the anastomosed stream) and swamp sediments. Sediment supply was mainly from the northwest, secondly from the east. From the beginning to the end of the terrigenous basin evolution, the area of sedimentation was gradually enlarged. The palaeo-topography became increasingly flat. 展开更多
关键词 Sedimentary facies evolution sunda basin
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The Formation and Evolution of the Sun and the Source of Star Energy as Well as the Sunspots and Flares of the Sun 被引量:2
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作者 Cuixiang Zhong 《Journal of Physical Science and Application》 2019年第2期17-25,共9页
Nebula theory is the most widely accepted hypothesis about the formation and evolution of the Solar System. This theoryholds that the Sun is formed from a collapsed gas cloud 4.57 billion years ago;when the core tempe... Nebula theory is the most widely accepted hypothesis about the formation and evolution of the Solar System. This theoryholds that the Sun is formed from a collapsed gas cloud 4.57 billion years ago;when the core temperature of the gas cloud rises to 10million K, the thermonuclear reaction of hydrogen fusion into helium is ignited, then the Sun become a star;once the hydrogen in thecore is exhausted, the life of the star will end. But the limited hydrogen element obviously cannot satisfy such a long-termthermonuclear reaction, in order to sustain long-term thermonuclear reactions, a steady stream of fuel must be obtained from space.So the existing hypothesis about the formation and evolution of the Solar System has serious defects. Thus the author has studied theformation of the Moon, the Earth and the Sun, and discovered the formation of the Sun and the real source of star energy. The authorcould also explain many solar activity phenomena such as sunspots, flares, prominences, etc. 展开更多
关键词 sun FORMATION evolution star energy sunSPOTS flares.
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Evolution of the Level of Sunspot Activity in Solar Cycles I. Evolution in the Descending Phase 被引量:2
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作者 Jia-Long Wang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第3期354-362,共9页
Taking the 13-point smoothed monthly sunspot number,Ri, and the deviation of the 13 associated monthly sunspot numbers from the smoothed one, Di, as a number-pair describing the global level of sunspot activity, the e... Taking the 13-point smoothed monthly sunspot number,Ri, and the deviation of the 13 associated monthly sunspot numbers from the smoothed one, Di, as a number-pair describing the global level of sunspot activity, the evolution of the level is statistically studied for the period from the month which is just 48 months before the minimum to the minimum in the descending phase, using the observed data of Solar Cycles 10 to 22. Our results show (1) for 46 months (94%) of the studied 49 months it is found that for a given month, the distribution of the 13 pairs which come from the 13 solar cycles on a log Ri - Di plane may be fitted by a straight line with a correlation coefficient larger than the critical one at confidence level a = 5%, and for 36 months (73%) the fitting is even better, for a = 1%; (2) time variations of these two parameters and their correlations in the studied period can be described respectively by functions of time, whose main trends may be expressed by a linear or simple curvilinear function; (3) the evolutionary path of the level of sunspot activity may be represented by a logarithmic function as log/~ = 0.704 lnDi - 0.291. 展开更多
关键词 sun - sunspots - active level evolution
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Evolution of a Long-lived Sunspot Group and Its Associated Solar-terrestrial Events 被引量:1
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作者 Gui-QingZhang Li-RongTian 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2005年第1期77-86,共10页
A long-lived sunspot group (AR9604) on the south hemisphere that lasted five solar rotations and produced some strong bursts is analyzed. The focus is on its evolving features. Its whole life was successfully maintain... A long-lived sunspot group (AR9604) on the south hemisphere that lasted five solar rotations and produced some strong bursts is analyzed. The focus is on its evolving features. Its whole life was successfully maintained by four Emerging Flux Regions (EFRs). Apart from the one that lasted only a short time and did not produce any bursts, the other three EFRs have the following common features: (1) A positive writhe of magnetic flux tubes and a twist of the field lines of the same sign, indicating kink instability. (2) A clockwise rotation and a high tilt because the writhe was right-handed. (3) A compact 'island δ' structure of the sunspot group indicating concentrated kink instability. Since magnetic reconnection easily occurs at the kinked point of a very kink-unstable flux tube, these features should be the inducement of the strong bursts. 展开更多
关键词 sun - active region evolution
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miR-516b-5p靶向NSUN2对乳腺癌细胞增殖和侵袭的影响
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作者 程欣然 范亚楠 +1 位作者 刘俊 皮亚平 《河北医学》 2025年第10期1585-1592,共8页
目的:探讨微小非编码RNA-516b-5p(miR-516b-5p)靶向RNA甲基转移酶家族成员2(NSUN2)对乳腺癌(BC)细胞增殖和侵袭的影响。方法:qRT-PCR实验检测BC癌组织、癌旁组织(n=45)及正常乳腺上皮细胞(MCF-10A)、BC细胞(MCF-7、MDA-MB-231、HCC1937)... 目的:探讨微小非编码RNA-516b-5p(miR-516b-5p)靶向RNA甲基转移酶家族成员2(NSUN2)对乳腺癌(BC)细胞增殖和侵袭的影响。方法:qRT-PCR实验检测BC癌组织、癌旁组织(n=45)及正常乳腺上皮细胞(MCF-10A)、BC细胞(MCF-7、MDA-MB-231、HCC1937)中miR-516b-5p、NSUN2 mRNA表达量。将MCF-7细胞分为NC组、miR-NC组、miR-516b-5p mimic组、sh-NC组、sh-NSUN2组、miR-516b-5p mimic+pcDNA-NC组、miR-516b-5p mimic+pcDNA-NSUN2组,通过克隆形成和Transwell侵袭实验分别检测各组MCF-7细胞增殖和侵袭能力;Western blot实验检测各组细胞中NSUN2、细胞周期蛋白1(CCND1)、细胞周期蛋白依赖性激酶1(CDK1)、基质金属蛋白酶2(MMP2)、基质金属蛋白酶9(MMP9)蛋白表达量;构建裸鼠BC移植瘤模型,并分为Model组、miR-516b-5p mimics组、miR-516b-5p mimic+pcDNA-NSUN2组,测量各组肿瘤质量和体积。结果:与癌旁组织相比,癌组织中miR-516b-5p表达量明显下降,NSUN2 mRNA表达量明显上升(P<0.05)。与MCF-10A细胞相比,MCF-7、MDA-MB-231、HCC1937细胞中miR-516b-5p表达量明显下降,NSUN2 mRNA表达量明显上升(P<0.05),其中MCF-7细胞以上指标变化趋势最为明显。与NC组相比,miR-NC组和sh-NC组细胞各指标无明显变化(P>0.05);与miR-NC组相比,miR-516b-5p mimic组细胞集落形成数量、侵袭细胞数减少,NSUN2 mRNA和NSUN2、CCND1、CDK1、MMP2、MMP9蛋白表达量均明显下降,miR-516b-5p表达量明显上升(P<0.05);与sh-NC组相比,sh-NSUN2组各指标变化趋势与miR-516b-5p mimic组一致(P<0.05);而在miR-516b-5p mimic+pcDNA-NSUN2组中各指标变化趋势与miR-516b-5p mimic组相反(P<0.05)。双荧光素酶实验证实miR-516b-5p与NSUN2存在靶向关系(P<0.05)。裸鼠成瘤实验中,与Model组相比,miR-516b-5p mimics组肿瘤组织质量和体积明显缩小(P<0.05);与miR-516b-5p mimics组相比,miR-516b-5p mimic+pcDNA-NSUN2组肿瘤组织质量和体积明显增大(P<0.05)。结论:miR-516b-5p可通过靶向下调NSUN2表达,抑制BC细胞增殖和侵袭。 展开更多
关键词 微小非编码RNA-516b-5p RNA甲基转移酶家族成员2 乳腺癌 增殖 侵袭
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Genome sequence and transcriptome of Sorbus pohuashanensis provide insights into population evolution and leaf sunburn response 被引量:2
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作者 Dongxue Zhao Yan Zhang +4 位作者 Yizeng Lu Liqiang Fan Zhibin Zhang Jian Zheng Mao Chai 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2022年第6期547-558,共12页
Sorbus pohuashanensis(Hance) Hedl. is a potential horticulture and medicinal plant, but its genomic and genetic backgrounds remain unknown. Here, we sequence and assemble the S. pohuashanensis reference genome using P... Sorbus pohuashanensis(Hance) Hedl. is a potential horticulture and medicinal plant, but its genomic and genetic backgrounds remain unknown. Here, we sequence and assemble the S. pohuashanensis reference genome using Pac Bio long reads. Based on the new reference genome, we resequence a core collection of22 Sorbus spp. samples, which are divided into 2 groups(G1 and G2) based on phylogenetic and PCA analyses. These phylogenetic clusters are highly consistent with their classification based on leaf shape.Natural hybridization between the G1 and G2 groups is evidenced by a sample(R21) with a highly heterozygous genotype. Nucleotide diversity(π) analysis shows that G1 has a higher diversity than G2 and that G2 originated from G1. During the evolution process, the gene families involved in photosynthesis pathways expanded and the gene families involved in energy consumption contracted. RNA-seq data suggests that flavonoid biosynthesis and heat-shock protein(HSP)-heat-shock factor(HSF) pathways play important roles in protection against sunburn. This study provides new insights into the evolution of Sorbus spp.genomes. In addition, the genomic resources, and the identified genetic variations, especially those related to stress resistance, will help future efforts to produce and breed Sorbus spp. 展开更多
关键词 Sorbus pohuashanensis Genome assembly Population evolution sunBURN
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Photocatalytic H_2 evolution activity of CuO/ZrO_2 composite catalyst under simulated sunlight irradiation 被引量:2
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作者 阎建辉 姚茂海 +2 位作者 张丽 唐有根 杨海华 《Journal of Central South University》 SCIE EI CAS 2011年第1期56-62,共7页
Zirconia-supported CuO (CuO/ZrO2) composite photocatalysts were successfully synthesized via citric acid-assisted sol-gel technique. For comparison, CuO/ZrO2 materials were also prepared by solid state reaction and ... Zirconia-supported CuO (CuO/ZrO2) composite photocatalysts were successfully synthesized via citric acid-assisted sol-gel technique. For comparison, CuO/ZrO2 materials were also prepared by solid state reaction and co-precipitation method. The as-prepared powders were characterized by X-ray diffractometry (XRD), transmission electron microscopy (TEM), and thermogravimetric-differential thermal analysis (TG-DTA). The photocatalytic activity of CuO/ZrO2 catalyst was investigated based on the H2 evolution from oxalic acid solution under simulated sunlight irradiation. The effects of molar ratio of CuO to ZrO2, preparation method, phase change with the calcination temperature and the durability on the photocatalytic activity of the photocatalyst were investigated in detail. It is found that the optimal activity of photocatalytic H2 evolution (2.41 mmol.h i.g-~) can be obtained when CuO/ZrO2 composite photocatalyst is synthesized by sol-gel technique and the mole ratio of CuO to ZrO2 is 40%. The activity of copper oxide supported on monoclinic ZrO2 calcined at higher temperature is much higher than that on tetragonal ZrO2 calcined at lower temperature, and the best calcination temperature is 900 ℃. 展开更多
关键词 CuO/ZrO2 photocatalytic activity hydrogen evolution simulated sunlight
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Multiple cycles of magnetic activity in the Sun and Sun-like stars and their evolution
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作者 Elena Aleksandrovna Bruevich Vasily Vladimirovich Bruevich Boris Pavlovich Artamonov 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第7期21-36,共16页
The wavelet transform method for high-quality time-frequency analysis is applied to sets of observations of relative sunspot numbers and stellar chromosphere fluxes of 10 Sun-like stars. Wavelet analysis of solar data... The wavelet transform method for high-quality time-frequency analysis is applied to sets of observations of relative sunspot numbers and stellar chromosphere fluxes of 10 Sun-like stars. Wavelet analysis of solar data shows that in a certain interval of time there are several cycles of activity with pe- riods of duration which vary considerably from each other: from quasi-biennial cycles to lO0-yr cycles. Cyclic activity was detected in almost all Sun-like stars that we examined, even those that previously were not considered as stars with cyclic activity according to analysis using a Scargle periodogram. The durations of solar and stellar cycles significantly change during the observation period. 展开更多
关键词 sun activity - multiple cycles - sun-like stars ACTIVITY
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NSUN2通过介导ARMC9的m5C修饰促进胃癌细胞的增殖、转移和侵袭
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作者 李越 陈栋 +4 位作者 王瑾 彭怡 张远琦 杨芬 王学军 《中国药科大学学报》 北大核心 2025年第5期583-591,共9页
为研究NOP2/Sun RNA甲基转移酶2(NOP2/Sun RNA methyltransferase 2,NSUN2)对胃癌恶性进展的影响及其潜在机制,使用TCGA数据库分析发现胃癌组织中NSUN2表达水平显著升高;Western blot发现,与胃黏膜上皮细胞相比,NSUN2在胃癌细胞中表达上... 为研究NOP2/Sun RNA甲基转移酶2(NOP2/Sun RNA methyltransferase 2,NSUN2)对胃癌恶性进展的影响及其潜在机制,使用TCGA数据库分析发现胃癌组织中NSUN2表达水平显著升高;Western blot发现,与胃黏膜上皮细胞相比,NSUN2在胃癌细胞中表达上调;集落形成实验显示,NSUN2过表达细胞中集落形成能力增高;Transwell实验也证实NSUN2高表达时,发生迁移和侵袭的细胞数量显著增多。进一步通过数据库分析推测ARMC可能是NSUN2的下游靶分子,接着通过MeRIP-qPCR揭示NSUN2高表达可以提高ARMC9的m5C修饰水平,并且降低ARMC9 mRNA的降解速率,从而提高其蛋白表达水平。此外,过表达ARMC9可以增强细胞的集落形成能力和迁移侵袭能力。上述结果显示,NSUN2可以通过提高ARMC9 mRNA的m5C修饰水平,提高其稳定性,增强其表达,从而促进胃癌进展,因此NSUN2和ARMC9可以作为胃癌进展的潜在治疗靶标。 展开更多
关键词 5-甲基胞嘧啶 甲基转移酶 NOP2/sun RNA甲基转移酶2 犰狳重复序列9 胃癌 肿瘤标志物
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Solving the Olbers’s Paradox, Explaining the “Red-Shift”, and Challenging the Relativities by “Sun Matters Theory” and “Sun Model of Universe”, an Evolution of the Einstein’s Static Universe Model
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作者 Wanpeng Sun 《Natural Science》 2024年第2期7-18,共12页
Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used ... Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used to partially explain this paradox, while introducing new problems. Hereby, we propose a better theory, named Sun Matters Theory, to explain this paradox. Moreover, this unique theory supports and extended the Einstein’s static universe model proposed by Albert Einstein in 1917. Further, we proposed our new universe model, “Sun Model of Universe”. Based on the new model and novel theory, we generated innovative field equation by upgrading Einstein’s Field Equation through adding back the cosmological constant, introducing a new variable and modifying the gravitationally-related concepts. According to the Sun Model of Universe, the dark matter and dark energy comprise the so-called “Sun Matters”. The observed phenomenon like the red shift is explained as due to the interaction of ordinary light with Sun Matters leading to its energy and frequency decrease. In Sun Model, our big universe consists of many universes with ordinary matter at the core mixed and surrounded with the Sun Matters. In those universes, the laws of physics may be completely or partially different from that of our ordinary universe with parallel civilizations. The darkness of night can be easily explained as resulting from the interaction of light with the Sun Matters leading to the sharp decrease in the light intensity. Sun Matters also scatter the light from a star, which makes it shining as observed by Hubble. Further, there is a kind of Sun Matters named “Sun Waters”, surrounding every starts. When lights pass by the sun, the Sun Waters deflect the lights to bend the light path. According to the Sun Model, it is the light bent not the space bent that was proposed in the theory of relativities. 展开更多
关键词 Olbers’s Paradox sun Matters Theory sun Model of Universe Einstein’s Universe Dark Mass
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Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis 被引量:1
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作者 Jie Wang Wei Wang +4 位作者 Xuheng Chen Junfang Bao Qiuyue Hao Heng Zheng Runsheng Xu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期58-69,共12页
The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the micro... The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was investigated.Furthermore,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric method.The findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and interconnect.This provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron coke.Accelerating the heating rate in non-isothermal gasification can enhance the reactivity of iron coke.The metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon atoms.The kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore structure.Moreover,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%. 展开更多
关键词 low-carbon ironmaking iron coke GASIFICATION structural evolution kinetic model
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Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption 被引量:1
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作者 Zizhuang He Lingzi Shi +6 位作者 Ran Sun Lianfei Ding Mukun He Jiaming Li Hua Guo Tiande Gao Panbo Liu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期191-204,共14页
Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significan... Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase evolution.Herein,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation process.The results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial polarization.Moreover,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic diffraction.Specifically,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon matrix.This design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption. 展开更多
关键词 Magnetic heterointerfaces Phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption
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SUN2调控稳定表达绵羊肺腺瘤病毒囊膜蛋白的OAR-L1细胞的恶性转化能力的研究
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作者 鲍安玉 杜晓悦 +3 位作者 陈思旭 段续接 张培 刘淑英 《中国兽医科学》 北大核心 2025年第5期669-677,共9页
为了探究SAD1/UN84结构域蛋白-2(SAD1/UNC84 domain protein-2,SUN2)在绵羊肺腺瘤病(ovine pulmonary adenocarcnoma,OPA)肿瘤细胞恶性转化中的功能,本试验利用实验室保存的JSRV env慢病毒感染绵羊肺成纤维细胞(OAR-L1),建立了OAR-L1-En... 为了探究SAD1/UN84结构域蛋白-2(SAD1/UNC84 domain protein-2,SUN2)在绵羊肺腺瘤病(ovine pulmonary adenocarcnoma,OPA)肿瘤细胞恶性转化中的功能,本试验利用实验室保存的JSRV env慢病毒感染绵羊肺成纤维细胞(OAR-L1),建立了OAR-L1-Env稳转株。通过qPCR和Western-blot检测JSRV Env和SUN2的表达情况,使用CCK-8、划分愈合试验和软琼脂糖集落形成试验检测细胞的恶性转化能力。此外,分别构建SUN2过表达和干扰质粒,并转染OAR-L1-Env稳转株,利用qPCR和Western-blot检测其SUN2的表达情况,通过CCK-8和划分愈合试验检测细胞的增殖和迁移能力。结果显示,OAR-L1-Env稳转株成功建立,且SUN2表达量显著下调(P<0.05),CCK-8、划分愈合试验和软琼脂糖集落形成试验表明OAR-L1-Env稳转株发生恶性转化。OAR-L1-Env稳转株中过表达SUN2可抑制细胞的增殖和迁移能力(P<0.05),而干扰SUN2则促进细胞的增殖和迁移能力(P<0.05)。综上所述,本研究表明SUN2参与调控JSRV Env诱导的细胞恶性转化,提示其可能对OPA肿瘤生成有抑制作用。本研究为进一步探究SUN2在OPA中的细胞增殖等生物学作用的研究提供了一定的参考资料。 展开更多
关键词 稳转株 囊膜蛋白 sun2 增殖 迁移
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Ru⁃doped Co_(3)O_(4)/reduced graphene oxide:Preparation and electrocatalytic oxygen evolution property 被引量:1
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作者 TIAN Tian ZHOU Meng +5 位作者 WEI Jiale LIU Yize MO Yifan YE Yuhan JIA Wenzhi HE Bin 《无机化学学报》 北大核心 2025年第2期385-394,共10页
Binary composites(ZIF-67/rGO)were synthesized by one-step precipitation method using cobalt nitrate hexahydrate as metal source,2-methylimidazole as organic ligand,and reduced graphene oxide(rGO)as carbon carrier.Then... Binary composites(ZIF-67/rGO)were synthesized by one-step precipitation method using cobalt nitrate hexahydrate as metal source,2-methylimidazole as organic ligand,and reduced graphene oxide(rGO)as carbon carrier.Then Ru3+was introduced for ion exchange,and the porous Ru-doped Co_(3)O_(4)/rGO(Ru-Co_(3)O_(4)/rGO)composite electrocatalyst was prepared by annealing.The phase structure,morphology,and valence state of the catalyst were analyzed by X-ray powder diffraction(XRD),scanning electron microscope(SEM),transmission electron microscopy(TEM),and X-ray photoelectron spectroscopy(XPS).In 1 mol·L^(-1)KOH,the oxygen evolution reaction(OER)performance of the catalyst was measured by linear sweep voltammetry,cyclic voltammetry,and chronoamperometry.The results show that the combination of Ru doping and rGO provides a fast channel for collaborative electron transfer.At the same time,rGO as a carbon carrier can improve the electrical conductivity of Ru-Co_(3)O_(4)particles,and the uniformly dispersed nanoparticles enable the reactants to diffuse freely on the catalyst.The results showed that the electrochemical performance of Ru-Co_(3)O_(4)/rGO was much better than that of Co_(3)O_(4)/rGO,and the overpotential of Ru-Co_(3)O_(4)/rGO was 363.5 mV at the current density of 50 mA·cm^(-2). 展开更多
关键词 metal-organic framework GRAPHENE ELECTROCATALYST oxygen evolution reaction
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Design Guidelines for Composition of Brazing Filler Metals and Evolution Mechanisms of Typical Microstructures 被引量:6
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作者 Long Weimin 《稀有金属材料与工程》 北大核心 2025年第4期837-853,共17页
Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler ... Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects. 展开更多
关键词 design of brazing filler metals design guidelines for composition Ag based brazing filler metals eutectic structures evolution
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P,N co-doped hollow carbon nanospheres prepared by micellar copolymerization for increased hydrogen evolution in alkaline water 被引量:1
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作者 HAN Yi-meng XIONG Hao +2 位作者 YANG Jia-ying WANG Jian-gan XU Fei 《新型炭材料(中英文)》 北大核心 2025年第1期211-221,共11页
The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alka... The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alkaline water.Precise control of the electronic structure by heteroatom doping has proven to be efficient for increasing catalytic activity.Nevertheless,both the structural characteristics and the underlying mechanism are not well understood,especially for doping with two different atoms,thus limiting the use of these catalysts.We report the production of phosphorus and nitrogen co-doped hollow carbon nanospheres(HCNs)by the copolymerization of pyrrole and aniline at a Triton X-100 micelle-interface,followed by doping with phytic acid and carbonization.The unique pore structure and defect-rich framework of the HCNs expose numerous active sites.Crucially,the combined effect of graphitic nitrogen and phosphorus-carbon bonds modulate the local electronic structure of adjacent C atoms and facilitates electron transfer.As a res-ult,the HCN carbonized at 1100°C exhibited superior HER activity and an outstanding stability(70 h at a current density of 10 mA cm^(−2))in alkaline water,because of the large number of graphitic nitrogen and phosphorus-carbon bonds. 展开更多
关键词 Alkaline hydrogen evolution ELECTROCATALYSTS Hollow carbon nanospheres Dual atoms doping Combined effect
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Metal-organic framework-derived sulfur-doped iron-cobalt tannate nanorods for efficient oxygen evolution reaction performance 被引量:1
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作者 ZHAI Haoying WEN Lanzong +3 位作者 LIAO Wenjie LI Qin ZHOU Wenjun CAO Kun 《无机化学学报》 北大核心 2025年第5期1037-1048,共12页
Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nano... Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nanorods,which had many voids.The S-FeCoTA catalysts exhibited excellent electrochemical oxygen evolution reaction(OER)performance with a low overpotential of 273 mV at 10 mA·cm^(-2)and a small Tafel slope of 36 mV·dec^(-1)in 1 mol·L^(-1)KOH.The potential remained at 1.48 V(vs RHE)at 10 mA·cm^(-2)under continuous testing for 15 h,implying that S-FeCoTA had good stability.The Faraday efficiency of S-FeCoTA was 94%.The outstanding OER activity of S-FeCoTA is attributed to the synergistic effects among S,Fe,and Co,thus promoting electron transfer,reducing the reaction kinetic barrier,and enhancing the OER performance. 展开更多
关键词 hydrothermal method tannic acid metal‑organic framework ELECTROCATALYSIS oxygen evolution reaction
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