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Na_(3)P interphase reduces Na nucleation energy enabling stable anode-less sodium metal batteries
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作者 Haizhao Yang Haifeng Lv +8 位作者 En Zhou Xiaohao Ji Chunnian Chen Haolei Yu Zhaowei Sun Dawei Zhang Hongchang Jin Xianghua Kong Hengxing Ji 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期448-455,共8页
Sodium metal batteries(SMBs)are rising as viable alternatives to lithium-ion systems due to their superior energy density and sodium's relative abundance.However,SMBs face significant impediments,particularly the ... Sodium metal batteries(SMBs)are rising as viable alternatives to lithium-ion systems due to their superior energy density and sodium's relative abundance.However,SMBs face significant impediments,particularly the exceedingly high negative-to-positive capacity ratios(N/P ratios)which severely encumber energy density and hinder their practical application.Herein,a novel nucleophilic Na_(3)P interphase on aluminum foil has been designed to significantly lower the nucleation energy barrier for sodium atom deposition,resulting in a remarkable reduction of nucleation overpotential and efficient mitigation of dendritic growth at high sodium deposition of 5 mA h cm^(−2).The interphase promotes stable cycling in anode-less SMB configurations with a low N/P ratio of 1.4 and high cathode mass loading of 11.5 mg cm^(−2),and demonstrates a substantial increase in high capacity retention of 92.4%after 500 cycles even under 1 C rate condition.This innovation signifies a promising leap forward in the development of high-energy-density,anode-less SMBs,offering a potential solution to the longstanding issues of cycle stability and energy efficiency. 展开更多
关键词 Anode-less Phosphorus anode nucleation buffer layer Sodium metal Dendrite-free
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Ribosome-inspired electrocatalysts inducing preferential nucleation and growth of three-dimensional lithium sulfide for high-performance lithium-sulfur batteries
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作者 Zhen Wu Wenfeng He +7 位作者 Jiahui Yang Yunuo Gu Ruiqi Yang Yiran Sun Jiajia Yuan Xin Wang Junwu Zhu Yongsheng Fu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期517-526,共10页
Nucleation of lithium sulfide(Li_(2)S)induced by electrocatalysts plays a crucial role in mitigating the shut-tle effect.However,short-chain polysulfides on electrocatalysts surfaces tend to re-dissolve into elec-trol... Nucleation of lithium sulfide(Li_(2)S)induced by electrocatalysts plays a crucial role in mitigating the shut-tle effect.However,short-chain polysulfides on electrocatalysts surfaces tend to re-dissolve into elec-trolytes,delaying Li_(2)S supersaturation and its nucleation.In this study,we draw inspiration from the ribosome-driven protein synthesis process in cells to prepare ultrasmall nitrogen-doped MoS_(2) nanocrys-tals anchored on porous nitrogen-doped carbon networks(N-MoS_(2)-NC)electrocatalysts.Excitedly,the ex-situ SEM demonstrates that ribosome-inspired N-MoS_(2)-NC electrocatalysts induce early nucleation and rapid growth of three-dimensional Li_(2)s during discharge.Theoretical calculations reveal that the Li-s bond length in N-MoS_(2)-Li_(2)S(100)is shorter,and the corresponding interfacial formation energy is lower than in MoS_(2)-Li_(2)S(100).This accelerated conversion of lithium polysulfides to Li_(2)S can enhance the utilization of active substances and inhibit the shuttle effect.This study highlights the potential of ribosome-inspired N-MoS_(2)-NC in improving the electrochemical stability of Li-S batteries,providing valuable insights for future electrocatalyst design. 展开更多
关键词 Lithium-sulfur batteries ELECTROCATALYSTS Nanocrystals Ribosome-inspired nucleation and growth
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Driving inward growth of lithium metal in hollow microcapsule hosts by heteroatom‐controlled nucleation
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作者 Siwon Kim Hong Rim Shin +2 位作者 Ki Jae Kim Min‐Sik Park Jong‐Won Lee 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期262-272,共11页
The application of Li metal anodes in rechargeable batteries is impeded by safety issues arising from the severe volume changes and formation of dendritic Li deposits.Three‐dimensional hollow carbon is receiving incr... The application of Li metal anodes in rechargeable batteries is impeded by safety issues arising from the severe volume changes and formation of dendritic Li deposits.Three‐dimensional hollow carbon is receiving increasing attention as a host material capable of accommodating Li metal inside its cavity;however,uncontrollable and nonuniform deposition of Li remains a challenge.In this study,we synthesize metal–organic framework‐derived carbon microcapsules with heteroatom clusters(Zn and Ag)on the capsule walls and it is demonstrated that Ag‐assisted nucleation of Li metal alters the outward‐to‐inward growth in the microcapsule host.Zn‐incorporated microcapsules are prepared via chemical etching of zeolitic imidazole framework‐8 polyhedra and are subsequently decorated with Ag by a galvanic displacement reaction between Ag^(+)and metallic Zn.Galvanically introduced Ag significantly reduces the energy barrier and increases the reaction rate for Li nucleation in the microcapsule host upon Li plating.Through combined electrochemical,microstructural,and computational studies,we verify the beneficial role of Ag‐assisted Li nucleation in facilitating inward growth inside the cavity of the microcapsule host and,in turn,enhancing electrochemical performance.This study provides new insights into the design of reversible host materials for practical Li metal batteries. 展开更多
关键词 hollow carbon hosts lithium metal batteries lithium plating metal-organic frameworks nucleation
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Formation and transformation of metastable LPSO building blocks clusters in Mg-Gd-Y-Zn-Zr alloys by spinodal decomposition and heterogeneous nucleation
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作者 Xin Zhao Zhong Yang +2 位作者 Jiachen Zhang Minxian Liang Liying Wang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期673-686,共14页
To study the formation and transformation mechanism of long-period stacked ordered(LPSO)structures,a systematic atomic scale analysis was conducted for the structural evolution of long-period stacked ordered(LPSO)stru... To study the formation and transformation mechanism of long-period stacked ordered(LPSO)structures,a systematic atomic scale analysis was conducted for the structural evolution of long-period stacked ordered(LPSO)structures in the Mg-Gd-Y-Zn-Zr alloy annealed at 300℃~500℃.Various types of metastable LPSO building block clusters were found to exist in alloy structures at different temperatures,which precipitate during the solidification and homogenization process.The stability of Zn/Y clusters is explained by the first principles of density functional theory.The LPSO structure is distinguished by the arrangement of its different Zn/Y enriched LPSO structural units,which comprises local fcc stacking sequences upon a tightly packed plane.The presence of solute atoms causes local lattice distortion,thereby enabling the rearrangement of Mg atoms in the different configurations in the local lattice,and local HCP-FCC transitions occur between Mg and Zn atoms occupying the nearest neighbor positions.This finding indicates that LPSO structures can generate necessary Schockley partial dislocations on specific slip surfaces,providing direct evidence of the transition from 18R to 14H.Growth of the LPSO,devoid of any defects and non-coherent interfaces,was observed separately from other precipitated phases.As a result,the precipitation sequence of LPSO in the solidification stage was as follows:Zn/Ycluster+Mg layers→various metastable LPSO building block clusters→18R/24R LPSO;whereas the precipitation sequence of LPSO during homogenization treatment was observed to be as follows:18R LPSO→various metastable LPSO building block clusters→14H LPSO.Of these,14H LPSO was found to be the most thermodynamically stable structure. 展开更多
关键词 LPSO Spinodal decomposition Homogenization treatment CLUSTERS phase transformation
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Nucleation of Supercooled Water by Neutrons: Latitude Dependence and Implications for Cloud Modelling
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作者 Peter W. Wilson Elizabeth Wilson-Park Abraham G. Wilson 《Atmospheric and Climate Sciences》 2024年第2期221-232,共12页
It has recently been shown that incident particles, neutrons, can initiate the freezing in a supercooled water volume. This new finding may have ramifications for the interpretation of both experimental data on the nu... It has recently been shown that incident particles, neutrons, can initiate the freezing in a supercooled water volume. This new finding may have ramifications for the interpretation of both experimental data on the nucleation of laboratory samples of supercooled water and perhaps more importantly on the interpretation of ice nucleation involved in cloud physics. For example, if some fraction of the cloud nucleation previously attributed to dust, soot, or aerosols has been caused by cosmogenic neutrons, fresh consideration is required in the context of climate models. Moreover, as cosmogenic neutrons, most being muon-induced, have much greater flux at high latitudes, estimates of ice nucleates in these regions may be larger than required to accurately model cloud and condensation properties. This discrepancy has been pointed out in IPCC reports. Our paper discusses the connection between the new concept of neutrons nucleating supercooled water and the need for a new source of nucleation in high latitude clouds, ideally causing others to review current data, or to analyse future data with this idea in mind. . 展开更多
关键词 Climate Models Ice nucleation Neutrons SUPERCOOLING
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Nucleation and growth control for iron-and phosphorus-rich phases from a modified steelmaking waste slag
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作者 Juncheng Li Guoxuan Li +7 位作者 Feng Qiu Rong Wang Jinshan Liang Yi Zhong Dong Guan Jingwei Li Seetharaman Sridhar Zushu Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第2期378-387,共10页
Recovering the iron(Fe)and phosphorus(P)contained in steelmaking slags not only reduces the environmental burden caused by the accumulated slag,but also is the way to develop a circular economy and achieve sustainable... Recovering the iron(Fe)and phosphorus(P)contained in steelmaking slags not only reduces the environmental burden caused by the accumulated slag,but also is the way to develop a circular economy and achieve sustainable development in the steel industry.We had pre-viously found the possibility of recovering Fe and P resources,i.e.,magnetite(Fe_(3)O_(4)) and calcium phosphate(Ca_(10)P_(6)O_(25)),contained in steel-making slags by adjusting oxygen partial pressure and adding modifier B_(2)O_(3).As a fundamental study for efficiently recovering Fe and P from steelmaking slag,in this study,the crystallization behavior of the CaO-SiO_(2)-FeO-P_(2)O_(5)-B_(2)O_(3) melt has been observed in situ,using a confocal scanning laser microscope(CLSM).The kinetics of nucleation and growth of Fe-and P-rich phases have been calculated using a classical crys-tallization kinetic theory.During cooling,a Fe_(3)O_(4) phase with faceted morphology was observed as the 1st precipitated phase in the isothermal interval of 1300-1150℃,while Ca_(10)P_(6)O_(25),with rod-shaped morphology,was found to be the 2nd phase to precipitate in the interval of 1150-1000℃.The crystallization abilities of Fe_(3)O_(4) and Ca_(10)P_(6)O_(25) phases in the CaO-SiO_(2)-FeO-P_(2)O_(5)-B_(2)O_(3) melt were quantified with the in-dex of(T_(U)−T_(I))/T_(I)(where T_(I) represents the peak temperature of the nucleation rate and TU stands for that of growth rate),and the crystalliza-tion ability of Fe_(3)O_(4) was found to be larger than that of Ca_(10)P_(6)O_(25) phase.The range of crystallization temperature for Fe_(3)O_(4) and Ca_(10)P_(6)O_(25) phases was optimized subsequently.The Fe_(3)O_(4) and Ca_(10)P_(6)O_(25) phases are the potential sources for ferrous feedstock and phosphate fertilizer,respectively. 展开更多
关键词 steelmaking slag MAGNETITE calcium phosphate nucleation GROWTH KINETICS
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Magnesium vapor nucleation in phase transitions and condensation under vacuum conditions 被引量:4
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作者 杨成博 田阳 +3 位作者 曲涛 杨斌 徐宝强 戴永年 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第2期561-569,共9页
Recent findings related to coagulable magnesium vapor nucleation and growth in vacuum were assessed critically, with emphasis on understanding these processes at a fundamental molecular level. The effects of magnesium... Recent findings related to coagulable magnesium vapor nucleation and growth in vacuum were assessed critically, with emphasis on understanding these processes at a fundamental molecular level. The effects of magnesium vapor pressure, condensation temperature, and condensation zone temperature gradient on magnesium vapor nucleation in phase transitions and condensation from atomic collision and coacervation with collision under vacuum conditions were discussed. Magnesium powder and magnesium lump condensates were produced under different conditions and characterized by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The right condensation zone temperature approach to the liquid transition primarily improved the magnesium vapor concentration rate. The gas-solid phase transition was primarily inhibited by setting a small condenser temperature gradient. Under the right condensation temperature and temperature gradients, increasing magnesium vapor partial pressure improved crystallization and reduced the oxidation rate. 展开更多
关键词 magnesium vapor VACUUM phase transition CONDENSATION nucleation
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Molecular Dynamics Studies of Solid-Liquid Phase Transitions Ⅱ——Homogeneous Nucleation of (KI)_(108) Clusters
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作者 朱小蕾 彭盘英 +4 位作者 周耀民 姚杰 周志华 李人宇 黄锦凡 《分子科学学报》 CAS CSCD 1998年第1期35-41,共7页
在一系列分子动力学计算中,(KI)108离子簇冷却时自发地由液相变为立方面心相.在350K和400K的成核速率大于1036核/m3·s.由成核速率得到的固-液界面自由能约为50mJ/m2.
关键词 分子动力学模拟 成核速率 KI离子簇 相变
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基于CTA颅内动脉瘤形态联合PHASES评分对破裂出血预测研究
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作者 王金泉 黄吉淮 谢颖 《影像研究与医学应用》 2024年第4期31-34,共4页
目的:分析头颈部计算机断层扫描血管成像(CTA)联合PHASES评分对颅内动脉瘤(IA)破裂出血的预测价值。方法:回顾性分析2021年10月—2023年9月东莞市长安医院诊治的IA患者临床资料,根据IA破裂出血与否分为IA破裂组(n=46)和IA未破裂组(n=44)... 目的:分析头颈部计算机断层扫描血管成像(CTA)联合PHASES评分对颅内动脉瘤(IA)破裂出血的预测价值。方法:回顾性分析2021年10月—2023年9月东莞市长安医院诊治的IA患者临床资料,根据IA破裂出血与否分为IA破裂组(n=46)和IA未破裂组(n=44),收集两组临床资料,对比两组患者CTA影像瘤体特征参数和PHASES评分结果。采用受试者工作特征(ROC)曲线分析两者联合预测动脉瘤破裂的效能。结果:IA破裂组高血压、糖尿病发生率及PHASES评分均高于IA未破裂组,差异有统计学意义(P <0.05)。两组病灶位置以颈内动脉(ICA)和大脑中动脉(MCA)为主,但IA破裂组病灶位置在MCA的占比为41.30%,高于IA未破裂组的20.45%,瘤体>7 mm的最多(瘤体7~9.9 mm占65.22%),瘤体形态不规则占58.7%,未破裂组病灶位置在ICA最多(68.18%),瘤体<7 mm的居多(75.00%),瘤体形态规则囊状动脉瘤占93.18%,差异有统计学意义(P <0.05)。CTA瘤体特征参数比较,IA破裂组患者瘤颈宽度、瘤体高度、瘤体长度、动脉瘤最大直径、入射夹角、动脉瘤体颈比等参数均高于IA未破裂组,差异有统计学意义(P <0.05)。CTA瘤体特征参数+PHASES评分联合预测曲线下面积为0.916,高于CTA瘤体特征参数(0.901)和PHASES评分(0.731)。结论:CTA瘤体特征参数+PHASES评分联合预测IA患者破裂出血效能最佳。 展开更多
关键词 颅内动脉瘤 破裂出血 CTA phaseS评分
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Highly Reversible Zn Metal Anodes Enabled by Increased Nucleation Overpotential 被引量:4
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作者 Zhengqiang Hu Fengling Zhang +8 位作者 Anbin Zhou Xin Hu Qiaoyi Yan Yuhao Liu Faiza Arshad Zhujie Li Renjie Chen Feng Wu Li Li 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期197-209,共13页
Dendrite formation severely compromises further development of zinc ion batteries. Increasing the nucleation overpotential plays a crucial role in achieving uniform deposition of metal ions. However, this strategy has... Dendrite formation severely compromises further development of zinc ion batteries. Increasing the nucleation overpotential plays a crucial role in achieving uniform deposition of metal ions. However, this strategy has not yet attracted enough attention from researchers to our knowledge. Here, we propose that thermodynamic nucleation overpotential of Zn deposition can be boosted through complexing agent and select sodium L-tartrate(Na-L) as example. Theoretical and experimental characterization reveals L-tartrate anion can partially replace H_(2)O in the solvation sheath of Zn^(2+), increasing de-solvation energy. Concurrently, the Na^(+) could absorb on the surface of Zn anode preferentially to inhibit the deposition of Zn^(2+) aggregation. In consequence, the overpotential of Zn deposition could increase from 32.2 to 45.1 mV with the help of Na-L. The Zn-Zn cell could achieve a Zn utilization rate of 80% at areal capacity of 20 mAh cm^(-2). Zn-LiMn_(2)O_(4) full cell with Na-L additive delivers improved stability than that with blank electrolyte. This study also provides insight into the regulation of nucleation overpotential to achieve homogeneous Zn deposition. 展开更多
关键词 nucleation overpotential Complexing agent Zn batteries Zn deposition
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Inner-pore reduction nucleation of palladium nanoparticles in highly conductive wurster-type covalent organic frameworks for efficient oxygen reduction electrocatalysis 被引量:1
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作者 Weiwen Wang Lu Zhang +4 位作者 Tianping Wang Zhen Zhang Xiangnan Wang Chong Cheng Xikui Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期543-552,I0014,共11页
Covalent organic frameworks(COFs)have emerged as a class of promising supports for electrocatalysis because of their advantages including good crystallinity,highly ordered pores,and structural diversity.However,their ... Covalent organic frameworks(COFs)have emerged as a class of promising supports for electrocatalysis because of their advantages including good crystallinity,highly ordered pores,and structural diversity.However,their poor conductivity represents the main obstruction to their practical application.Here,we reported a novel synthesis strategy for synergistically endowing a triphenylamine-based COFs with improved electrical conductivity and excellent catalytic activity for oxygen reduction,via the in-situ redox deposition and confined growth of palladium nanoparticles inside the porous structure of COFs using reductive triphenylamine frameworks as reducing agent;meanwhile,the triphenylamine unit was oxidized to radical cation structure and affords radical cation COFs with conductivity as high as3.2*10^(-1) S m^(-1).Such a uniform confine palladium nanoparticle on highly conductive COFs makes it an efficient electrocatalyst for four-electron oxygen reduction reaction(4e-ORR),showing excellent activities and fast kinetics with a remarkable half-wave potential(E_(1/2))of 0.865 V and an ultralow Tafel slope of 39.7 mV dec^(-1) in alkaline media even in the absence of extra commercial conductive fillers.The generality of this strategy was proved by preparing the different metal and metal alloy nanoparticles supported on COFs(Au@COF,Pt@COF,AuPd@COF,AgPd@COF,and PtPd@COF)using reductive triphenylamine frameworks as reducing agent.This work not only provides a facile strategy for the fabrication of highly conductive COF supported ORR electrocatalysts,but also sheds new light on the practical application of Zn-air battery. 展开更多
关键词 Covalent organic frameworks Wurster-type structure In-situ reduction nucleation Palladium nanoparticles Oxygen reduction electrocatalysis
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Simultaneous refinement of α-Mg grains and β-Mg_(17)Al_(12) in Mg-Al based alloys via heterogeneous nucleation on Al_(8)Mn_(4)Sm 被引量:1
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作者 Jun-Chen Chen Mei-Xuan Li +4 位作者 Zhi-Yang Yu Zhao-Yuan Meng Cheng Wang Zhi-Zheng Yang Hui-Yuan Wang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第1期348-360,共13页
Due to the significant differences in the formation temperature and crystal structure between the primaryα-Mg and eutecticβ-Mg_(17)Al_(12),it is a great challenge to achieve simultaneous refinement of the primary an... Due to the significant differences in the formation temperature and crystal structure between the primaryα-Mg and eutecticβ-Mg_(17)Al_(12),it is a great challenge to achieve simultaneous refinement of the primary and eutectic phases in Mg-Al based alloys via heterogeneous nucleation.Surprisingly,we found that theα-Mg andβ-Mg_(17)Al_(12) in the AZ80 alloy can be simultaneously refined after 0.2 wt.%Sm addition,with the grain size decreasing from∼217±15μm to∼170±10μm and theβ-Mg_(17)Al_(12) morphology changing from a typical continuous network to a nod-like or spherical structure.The simultaneous refinement mechanism is investigated through solidification simulation,transmission electron microscopy(TEM),and differential thermal analysis(DTA).In the AZ80-0.2Sm alloy,many Al8Mn4Sm particles can be observed near the center of theα-Mg grains or inside theβ-Mg_(17)Al_(12).Crystallographic calculations further reveal that the Al8Mn4Sm has good crystallographic matching with both theα-Mg andβ-Mg_(17)Al_(12),so it possesses the potency to serve as heterogeneous nucleation sites for both phases.The promoted heterogeneous nucleation on the Al8Mn4Sm decreases the undercooling required by the nucleation of the primary and eutectic phases,which enhances the heterogeneous nucleation rate,thus causing the simultaneous refinement of theα-Mg andβ-Mg_(17)Al_(12).The orientation relationships between the Al8Mn4Sm and Mg/Mg_(17)Al_(12) are identified,which are[1210]_(Mg)//[010]_(Al8Mn4Sm),(1010)_(Mg)//(301)_(Al8Mn4Sm) and[112]_(Mg_(17)Al_(12))//[010]_(Al8Mn4Sm),(110)_(Mg_(17)Al_(12))//(301)_(Al8Mn4Sm),respectively.Furthermore,the refinement of theβ-Mg_(17)Al_(12) accelerates its dissolution during the solution treatment,which is beneficial for cost saving in industrial applications.Other Al8Mn4RE compounds such as Al8Mn4Y might have the same positive effect on the simultaneous refinement due to the similar physicochemical properties of rare earth elements.This work not only proves the possibility of simultaneously refining the primary and eutectic phases in Mg-Al based alloys via heterogeneous nucleation,but also provides new insights into the development of refiners for cast Mg alloys. 展开更多
关键词 Magnesium alloys Microstructure refinement Primaryα-Mg Eutecticβ-Mg_(17)Al_(12) Rare earth Heterogeneous nucleation
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NUCLEATION OF RARE EARTH-RICH PHASE PARTICLES IN Ti-5Al-4Sn-2Zr-1Mo-0.25Si-1Nd ALLOY 被引量:2
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作者 G.P.Li D.Li and Y. Y. Liu (Department of Titanium Alloys, Institute of Metal Research, The Chinese Academy of Sciences, Shenyang 110015, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1998年第4期265-269,共5页
High resolution electron microscopy studies of rure earth-rich phase particles in a melt-quenched Ti-5Al-4Sn-2Zr-1MO-0.25Si-1Nd alloy indicate that the α-Ti matrix crystallizes prior to the rare earth-rich phase part... High resolution electron microscopy studies of rure earth-rich phase particles in a melt-quenched Ti-5Al-4Sn-2Zr-1MO-0.25Si-1Nd alloy indicate that the α-Ti matrix crystallizes prior to the rare earth-rich phase particles. According to a new nucleation model, the heteropeneous nucleation of the rare earth-rich phase particles at the matrix interface is easier than the homogeneous nucleation off the interface matrix, which is consistent with the results of the HREM obseroations. 展开更多
关键词 Ti alloy rure earth rich phase nucleation
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Crystal plasticity model to predict fatigue crack nucleation based on the phase transformation theory 被引量:5
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作者 Lu Liu Jundong Wang +1 位作者 Tao Zeng Yao Yao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2019年第5期1033-1043,共11页
A crystal plasticity model is developed to predict the fatigue crack nucleation of polycrystalline materials,in which the accumulated dislocation dipoles are considered to be the origin of damage.To describe the overa... A crystal plasticity model is developed to predict the fatigue crack nucleation of polycrystalline materials,in which the accumulated dislocation dipoles are considered to be the origin of damage.To describe the overall softening behavior under cyclic loading,a slip system-level dislocation density-related damage model is proposed and implemented in the finite element analysis with Voronoi tessellation.The numerical model is applied to calibrate the stress-strain relationship at different cycles before fatigue crack nucleation.The parameters determined from the numerical analysis are substituted into a modified phase transformation model to predict the critical fatigue crack nucleation cycle.Comparing with the experimental results of Sn-3.0Ag-0.5Cu(SAC305)alloy and P91 steel,the proposed method can describe the constitutive behavior and predict the fatigue crack nucleation accurately. 展开更多
关键词 Fatigue CRACK nucleation Damage CRYSTAL PLASTICITY Finite element DISLOCATION density
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Phase-engineering modulation of Mn-based oxide cathode for constructing super-stable sodium storage 被引量:1
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作者 Quanqing Zhao Ruru Wang +5 位作者 Ming Gao Bolin Liu Jianfeng Jia Haishun Wu Youqi Zhu Chuanbao Cao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期421-427,I0010,共8页
The Mn-based oxide cathode with enriched crystal phase structure and component diversity can provide the excellent chemistry structure for Na-ion batteries.Nevertheless,the broad application prospect is obstructed by ... The Mn-based oxide cathode with enriched crystal phase structure and component diversity can provide the excellent chemistry structure for Na-ion batteries.Nevertheless,the broad application prospect is obstructed by the sluggish Na^(+)kinetics and the phase transitions upon cycling.Herein,we establish the thermodynamically stable phase diagram of various Mn-based oxide composites precisely controlled by sodium content tailoring strategy coupling with co-doping and solid-state reaction.The chemical environment of the P2/P'3 and P2/P3 biphasic composites indicate that the charge compensation mechanism stems from the cooperative contribution of anions and cations.Benefiting from the no phase transition to scavenge the structure strain,P2/P'3 electrode can deliver long cycling stability(capacity retention of 73.8%after 1000 cycles at 10 C)and outstanding rate properties(the discharge capacity of 84.08 mA h g^(-1)at 20 C)than P2/P3 electrode.Furthermore,the DFT calculation demonstrates that the introducing novel P'3 phase can significantly regulate the Na^(+)reaction dynamics and modify the local electron configuration of Mn.The effective phase engineering can provide a reference for designing other high-performance electrode materials for Na-ion batteries. 展开更多
关键词 Sodium ion battery Oxide cathode phase engineering phase diagram Na~+kinetic
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Different roles of surfaces’ interaction on lattice mismatched/matched surfaces in facilitating ice nucleation
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作者 傅宣豪 周昕 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期40-46,共7页
The freezing of water is one of the most common processes in nature and affects many aspects of human activity. Ice nucleation is a crucial part of the freezing process and usually occurs on material surfaces. There i... The freezing of water is one of the most common processes in nature and affects many aspects of human activity. Ice nucleation is a crucial part of the freezing process and usually occurs on material surfaces. There is still a lack of clear physical pictures about the central question how various features of material surfaces affect their capability in facilitating ice nucleation. Via molecular dynamics simulations, here we show that the detailed features of surfaces, such as atomic arrangements, lattice parameters, hydrophobicity, and function forms of surfaces’ interaction to water molecules, generally affect the ice nucleation through the average adsorption energy per unit-area surfaces to individual water molecules, when the lattice of surfaces mismatches that of ice. However, for the surfaces whose lattice matches ice, even the detailed function form of the surfaces’ interaction to water molecules can largely regulate the icing ability of these surfaces. This study provides new insights into understanding the diverse relationship between various microscopic features of different material surfaces and their nucleation efficacy. 展开更多
关键词 ice nucleation molecular simulations lattice match HYDROPHILICITY
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Bubble nucleation in spherical liquid cavity wrapped by elastic medium
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作者 张先梅 李凡 +5 位作者 王成会 胡静 莫润阳 沈壮志 郭建中 林书玉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期323-332,共10页
According to classical nucleation theory, gas nuclei can generate and grow into a cavitation bubble when the liquid pressure exceeds a threshold. However, classical nucleation theory does not include boundary effects.... According to classical nucleation theory, gas nuclei can generate and grow into a cavitation bubble when the liquid pressure exceeds a threshold. However, classical nucleation theory does not include boundary effects. An enclosed spherical liquid cavity surrounded by elastic medium is introduced to model the nucleation process in tissue. Based on the equilibrium pressure relationship of a quasi-static process, the expressions of the threshold and the modified nucleation rate are derived by considering the tissue elasticity. It is shown that the constraint plays an important role in the nucleation process. There is a positive correlation between nucleation threshold pressure and constraint, which can be enhanced by an increasing tissue elasticity and reducing the size of the cavity. Meanwhile, temperature is found to be a key parameter of nucleation process, and cavitation is more likely to occur in confined liquids at temperature T > 100℃. In contrast, less influences are induced by these factors, such as bulk modulus, liquid cavity size, and acoustic frequency. Although these theoretical predictions of the thresholds have been demonstrated by many previous researches, much lower thresholds can be obtained in liquids containing dissolved gases, e.g., the nucleation threshold is about-21 MPa in a liquid of 0.8-nm gas nuclei at room temperature. Moreover, when there is a gas nucleus of 20 nm, the theoretical threshold pressure might be less than1 MPa. 展开更多
关键词 elastic confinement liquid cavities cavitation nucleation
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Microscopic phase-field simulation for nucleation incubation time of Ni_(75)Al_xV_(25-x)alloy 被引量:2
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作者 李永胜 陈铮 +2 位作者 卢艳丽 王永欣 张建军 《Journal of Central South University of Technology》 EI 2005年第6期635-640,共6页
With the microscopic phase-field dynamic model, the effects of temperature and concentration on the nucleation incubation time of Ni75AlxV25-x alloy were studied and the relation between the incubation time and precip... With the microscopic phase-field dynamic model, the effects of temperature and concentration on the nucleation incubation time of Ni75AlxV25-x alloy were studied and the relation between the incubation time and precipitation mechanism was investigated by using the atomic occupation probability picture and average order parameter curve. The simulation results demonstrate that there exists the incubation time for different precipitation mechanisms~ such as non-classical nucleation, the mixed style of non-classical nucleation and spinodal decomposition, and spinodal ordering; and the incubation time shortens in turn for the three kinds of mechanisms. With the increase of Al content of Ni75AlxV25-x alloy, the incubation time of Llz phases shortens continuously and that of DOzz phases is prolonged. The effects of temperature on the incubation time of Llz and DOzz phases are accordant, i.e. the incuba- tion time is greatly prolonged with the temperature rising. 展开更多
关键词 microscopic phase-field nucleation incubation time order parameter SIMULATION
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Phase separation and transcriptional regulation in cancer development 被引量:1
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作者 Yan Gu Ke Wei Jun Wang 《Journal of Biomedical Research》 CAS CSCD 2024年第4期307-321,共15页
Liquid-liquid phase separation,a novel biochemical phenomenon,has been increasingly studied for its medical applications.It underlies the formation of membrane-less organelles and is involved in many cellular and biol... Liquid-liquid phase separation,a novel biochemical phenomenon,has been increasingly studied for its medical applications.It underlies the formation of membrane-less organelles and is involved in many cellular and biological processes.During transcriptional regulation,dynamic condensates are formed through interactions between transcriptional elements,such as transcription factors,coactivators,and mediators.Cancer is a disease characterized by uncontrolled cell proliferation,but the precise mechanisms underlying tumorigenesis often remain to be elucidated.Emerging evidence has linked abnormal transcriptional condensates to several diseases,especially cancer,implying that phase separation plays an important role in tumorigenesis.Condensates formed by phase separation may have an effect on gene transcription in tumors.In the present review,we focus on the correlation between phase separation and transcriptional regulation,as well as how this phenomenon contributes to cancer development. 展开更多
关键词 phase separation transcription regulation CANCER super-enhancer CONDENSATES
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Shikimic acid accelerates phase change and flowering in Chinese jujube 被引量:1
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作者 Xianwei Meng Zhiguo Liu +11 位作者 Li Dai Weiqiang Zhao Jiurui Wang Lili Wang Yuanpei Cui Ying Li Yinshan Cui Yao Zhang Luyao Wang Fengjiao Yu Jin Zhao Mengjun Liu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期413-424,共12页
The juvenile-to-adult phase change with first flowering as the indicator plays a crucial role in the lifecycle of fruit trees. However, the molecular mechanisms underlying phase change in fruit trees remain largely un... The juvenile-to-adult phase change with first flowering as the indicator plays a crucial role in the lifecycle of fruit trees. However, the molecular mechanisms underlying phase change in fruit trees remain largely unknown. Shikimic acid (ShA) pathway is a main metabolic pathway closely related to the synthesis of hormones and many important secondary metabolites participating in plant phase change. So,whether ShA regulates phase change in plants is worth clarifying. Here, the distinct morphological characteristics and the underlying mechanisms of phase change in jujube (Ziziphus jujuba Mill.), an important fruit tree native to China with nutritious fruit and outstanding tolerance abiotic stresses, were clarified. A combined transcriptome and metabolome analysis found that ShA is positively involved in jujube(Yuhong’×Xing 16’) phase change. The genes in the upstream of ShA synthesis pathway (ZjDAHPS, ZjDHQS and ZjSDH), the contents of ShA and the downstream secondary metabolites like phenols were significantly upregulated in the phase change period. Further, the treatment of spraying exogenous ShA verified that ShA at a very low concentration (60 mg·L^(-1)) can substantially speed up the phase change and flowering of jujube and other tested plants including Arabidopsis, tomato and wheat. The exogenous ShA (60 mg·L^(-1)) treatment in jujube seedlings could increase the accumulation of endogenous ShA, enhance leaf photosynthesis and the synthesis of phenols especially flavonoids and phenolic acids, and promote the expression of genes (ZjCOs, ZjNFYs and ZjPHYs) involved in flowering pathway. Basing on above results, we put forward a propose for the underlying mechanism of ShA regulating phase change, and a hypothesis that ShA could be considered a phytohormone-like substance because it is endogenous, ubiquitous, movable and highly efficient at very low concentrations. This study highlights the critical role of ShA in plant phase change and its phytohormone-like properties. 展开更多
关键词 Ziziphus jujuba Mill. phase change FLOWERING Shikimic acid TRANSCRIPTOME METABOLOME
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