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Enrichment of Fetal Nucleated Red Blood Cells by Multi-core Magnetic Composite Particles for Non-invasive Prenatal Diagnosis 被引量:1
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作者 PAN Ying WANG Qing +7 位作者 HUANG Wen-jun QIAO Feng-1i LIU Yu-ping ZHANG Yu-cheng HAI De-yang DU Ying,ting WANG Wen-yue ZHANG Ai-chen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第3期443-448,共6页
A novel kind of multi-core magnetic composite particles, the surfaces of which were respectively mo- dified with goat-anti-mouse IgG and antitransferrin receptor(anti-CD71), was prepared. The fetal nucleated red blo... A novel kind of multi-core magnetic composite particles, the surfaces of which were respectively mo- dified with goat-anti-mouse IgG and antitransferrin receptor(anti-CD71), was prepared. The fetal nucleated red blood cells(FNRBCs) in the peripheral blood of a gravida were rapidly and effectively enriched and separated by the mo- dified multi-core magnetic composite particles in an external magnetic field. The obtained FNRBCs were used for the identification of the fetal sex by means of fluorescence in situ hybridization(FISH) technique. The results demonstrate that the multi-core magnetic composite particles meet the requirements for the enrichment and speration of FNRBCs with a low concentration and the accuracy of detetion for the diagnosis of fetal sex reached to 95%. Moreover, the obtained FNRBCs were applied to the non-invasive diagnosis of Down syndrome and chromosome 3p21 was de- tected. The above facts indicate that the novel multi-core magnetic composite particles-based method is simple, relia- ble and cost-effective and has opened up vast vistas for the potential application in clinic non-invasive prenatal diag- nosis. 展开更多
关键词 Fetal nucleated red blood cell(FNRBC) Prenatal diagnosis NON-INVASIVE Multi-core magnetic compositeparticle
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Isolation of Fetal Nucleated Red Blood Cells from Maternal Blood 被引量:1
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作者 邹丽 叶晓静 +1 位作者 徐可树 朱剑文 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2000年第2期169-171,共3页
To find a simple, effective method of isolating fetal cells from maternal peripheral blood for prenatal diagnosis, 45 women were studied with their gestation being 6-14 weeks and age 21- 30 years. The fetal cells wer... To find a simple, effective method of isolating fetal cells from maternal peripheral blood for prenatal diagnosis, 45 women were studied with their gestation being 6-14 weeks and age 21- 30 years. The fetal cells were isolated from maternal blood by using discontinuous density gradient centrifugation. Some of the isolated cells were made smear and counted under the microscope; others were used for predicting fetal sex by PCR amplification of Y chromosome specific DYZ1 gene. The major cells in the upper separation interface were lymphocytes and monocytes, with occasionally seen nucleated red blood cells (NRBC); while those in the middle separation interface were neutrocytes, with NRBC scattering. The ratio of NRBC/nucleated cells was 1. 98±0. 28× 10-5. There was no significant difference between the first and second trimester (P>0. 05). The amount of isolated fetal cells was sufficient for prenatal genetic diagnosis. Male pregnancy was correctly predicted in 10 out of 13 cases. It is concluded that the method of discontinuous density gradient centrifugation was of considerable importance in the development of non-invasive prenatal genetic diagnosis. 展开更多
关键词 maternal peripheral blood nucleated red blood cell sex identification polymerase chain reaction
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Y Specific Sequence Gene Analysis of Single Fetal Nucleated Erythroblasts from the Peripheral Blood of Pregnant Women
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作者 王陶然 陈汉平 +1 位作者 卢运萍 马庭元 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2001年第2期163-165,共3页
The single cell isolation technique was used to detect fetal nucleated erythroblasts at a single cell level from the peripheral blood of pregnant women in order to investigate the feasibility of this method for nonin... The single cell isolation technique was used to detect fetal nucleated erythroblasts at a single cell level from the peripheral blood of pregnant women in order to investigate the feasibility of this method for noninvasive prenatal diagnosis. Single fetal nucleated erythroblasts were isolated from the peripheral blood samples from 51 pregnant women by micromanipulation techniques after density gradient centrifugation. Nested polymerase chain reaction method was used to amplify the SRY gene. It was found that the concordance rate of amplification results with real fetal sex was 82.61 %. The sensitivity and specificity were 80 % and 87.50 % respectively. It was suggested that it is feasible and promising in non invasive prenatal diagnosis to detect fetal nucleated erythroblasts at a single cell level by using micromanipulation techniques. 展开更多
关键词 single cell peripheral blood of pregnant woman fetal nucleated erythroblasts nested polymerase chain reaction
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Detection of Fetal Nucleated Erythrocytes and Fetal DNA from Peripheral Blood of Pregnant Women
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作者 张铭 陈汉平 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2003年第1期65-67,共3页
In order to search for a more reliable method of sorting fetal nucleated red blood cells (NRBCs) and DNA from maternal peripheral blood and to identify origin of NRBCs and DNA, NRBCs were isolated from peripheral bloo... In order to search for a more reliable method of sorting fetal nucleated red blood cells (NRBCs) and DNA from maternal peripheral blood and to identify origin of NRBCs and DNA, NRBCs were isolated from peripheral blood of 88 pregnant women by density gradient centrifugation and fluorescence activated cell sorter (FACS) respectively. Nested polymerase chain reaction was used to detect normal male SRY gene from blood plasma DNA of 65 pregnant women. The results revealed that fetal NRBCs were found in 14 of 27 maternal samples by density gradient centrifugation. The number of cells was from 1 to 10. Using FACS, CD71 + cells were identified among all 61 samples. The frequency was (0.35±0.25)×10 -2; The detectable rate of the SRY gene of blood plasma DNA from 46 women carrying male fetuses was 65.22 % (30/46). Non-detectable rate for 19 women carrying female fetuses was 94.74 % (18/19). It was concluded that the methods of sorting fetal NRBCs and DNA have already made great progress. The methods for fetal NRBCs and plasma DNA from maternal peripheral blood to diagnose genetic diseases seem to be the best methods of noninvasive prenatal diagnosis. 展开更多
关键词 nucleated red blood cells fetal DNA prenatal diagnosis
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Sn nucleation and growth from Sn(II)dissolved in ethylene glycol:Electrochemical behavior and temperature effect
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作者 Kiem Van DO Hieu Van NGUYEN Tu Manh LE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2714-2732,共19页
Thermodynamic and kinetic aspects of Sn nucleation and growth processes onto a glassy carbon electrode from SnCl2·2H2O dissolved in ethylene glycol solutions were studied.Typical reduction and oxidation peaks obs... Thermodynamic and kinetic aspects of Sn nucleation and growth processes onto a glassy carbon electrode from SnCl2·2H2O dissolved in ethylene glycol solutions were studied.Typical reduction and oxidation peaks observed in voltammograms have demonstrated the capability of ethylene glycol solutions to electrodeposit Sn.The temperature-dependence of diffusion coefficient values derived from potentiodynamic and potentiostatic studies helped to determine and validate estimations of the activation energy for Sn(II)bulk diffusion.Chronoamperometric results have identified that,the suitable model to describe the early stage of Sn electrodeposition could be composed of Sn three-dimensional nucleation and diffusion-controlled growth and water reduction contributions,which was duly validated by theoretical and experimental approaches.From the model,typical kinetic parameters such as the nucleation frequency of Sn(A),number density of Sn nuclei(N_(0)),and diffusion coefficient of Sn(II)ions(D),were determined.The presence of Sn nuclei with excellent quality and their structures were verified using SEM,EDX,and XRD techniques. 展开更多
关键词 SN NUCLEATION growth ethylene glycol nucleation kinetics ELECTRODEPOSITION
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The dual action of N_(2)on morphology regulation and mass-transfer acceleration of CO_(2)hydrate film
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作者 Jinrong Zhong Yu Tian +6 位作者 Yifei Sun Li Wan Yan Xie Yujie Zhu Changyu Sun Guangjin Chen Yuefei Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第9期120-129,共10页
The morphology characteristics of CH_(4),CO_(2),and CO_(2)+N_(2)hydrate film forming on the suspending gas bubbles are studied using microscopic visual method at supercooling conditions from 1.0 to 3.0 K.The hydrate f... The morphology characteristics of CH_(4),CO_(2),and CO_(2)+N_(2)hydrate film forming on the suspending gas bubbles are studied using microscopic visual method at supercooling conditions from 1.0 to 3.0 K.The hydrate film vertical growth rate and thickness along the planar gas-water interface are measured to study the hydrate formation kinetics and mass transfer process.Adding N_(2)in the gas mixture plays the same role as lowering the supercooling conditions,both retarding the crystal nucleation and growth rates,which results in larger single crystal size and rough hydrate morphology.N_(2)in the gas mixture helps to delay the secondary nucleation on the hydrate film,which is beneficial to maintain the porethroat structure and enhance the mass transfer.The vertical growth rate of hydrate film mainly depends on the supercooling conditions and gas compositions but has weak dependence on the experimental temperature and pressure.Under the same gas composition condition,the final film thickness shows a linear relationship with the supercooling conditions.The mass transfer coefficient of CH_(4)molecules in hydrates ranges from 4.54×10^(-8)to 7.54×10^(-8)mol·cm^(-2)·s^(-1)·MPa^(-1).The maximum mass transfer coefficient for CO_(2)t N_(2)hydrate occurs at the composition of 60%CO_(2)t 40%N_(2),which is 3.98×10^(-8)mol·cm^(-2)·s^(-1)·MPa^(-1). 展开更多
关键词 Gas hydrate MORPHOLOGY Secondary nucleation Formation kinetics Mass transfer
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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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Biomineralization and mineralization using microfluidics:A comparison study
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作者 Yang Xiao Xiang He +3 位作者 Guoliang Ma Chang Zhao Jian Chu Hanlong Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期661-669,共9页
Biomineralization through microbial process has attracted great attention in the field of geotechnical engineering due to its ability to bind granular materials,clog pores,and seal fractures.Although minerals formed b... Biomineralization through microbial process has attracted great attention in the field of geotechnical engineering due to its ability to bind granular materials,clog pores,and seal fractures.Although minerals formed by biomineralization are generally the same as that by mineralization,their mechanical behaviors show a significant discrepancy.This study aims to figure out the differences between biomineralization and mineralization processes by visualizing and tracking the formation of minerals using microfluidics.Both biomineralization and mineralization processes occurred in the Y-shaped sandcontaining microchip that mimics the underground sand layers.Images from different areas in the reaction microchannel of microchips were captured to directly compare the distribution of minerals.Crystal size and numbers from different reaction times were measured to quantify the differences between biomineralization and mineralization processes in terms of crystal kinetics.Results showed that the crystals were precipitated in a faster and more uncontrollable manner in the mineralization process than that in the biomineralization process,given that those two processes presented similar precipitation stages.In addition,a more heterogeneous distribution of crystals was observed during the biomineralization process.The precipitation behaviors were further explained by the classical nucleation crystal growth theory.The present microfluidic tests could advance the understanding of biomineralization and provide new insight into the optimization of biocementation technology. 展开更多
关键词 Microbially induced carbonate precipitation (MICP) Biocementation CRYSTAL Calcium carbonate NUCLEATION
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Description of martensitic transformation kinetics in Fe-C-X(X = Ni,Cr,Mn,Si) system by a modified model
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作者 Xiyuan Geng Hongcan Chen +3 位作者 Jingjing Wang Yu Zhang Qun Luo Qian Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期1026-1036,共11页
Controlling the content of athermal martensite and retained austenite is important to improving the mechanical properties of high-strength steels,but a mechanism for the accurate description of martensitic transformat... Controlling the content of athermal martensite and retained austenite is important to improving the mechanical properties of high-strength steels,but a mechanism for the accurate description of martensitic transformation during the cooling process must be addressed.At present,frequently used semi-empirical kinetics models suffer from huge errors at the beginning of transformation,and most of them fail to exhibit the sigmoidal shape characteristic of transformation curves.To describe the martensitic transformation process accurately,based on the Magee model,we introduced the changes in the nucleation activation energy of martensite with temperature,which led to the varying nucleation rates of this model during martensitic transformation.According to the calculation results,the relative error of the modified model for the martensitic transformation kinetics curves of Fe-C-X(X = Ni,Cr,Mn,Si) alloys reached 9.5% compared with those measured via the thermal expansion method.The relative error was approximately reduced by two-thirds compared with that of the Magee model.The incorporation of nucleation activation energy into the kinetics model contributes to the improvement of its precision. 展开更多
关键词 Fe-C-X system martensitic transformation kinetics curve semi-empirical model nucleation activation energy
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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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Effects of gallium surfactant on AlN thin films by microwave plasma chemical vapor deposition
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作者 Lu Wang Xulei Qin +8 位作者 Li Zhang Kun Xu Feng Yang Shaoqian Lu Yifei Li Bosen Liu Guohao Yu Zhongming Zeng Baoshun Zhang 《Journal of Semiconductors》 EI CAS CSCD 2024年第9期53-60,共8页
In this work, AlN films were grown using gallium (Ga) as surfactant on 4° off-axis 4H-SiC substrates via microwave plasma chemical vapor deposition (MPCVD). We have found that AlN growth rate can be greatly impro... In this work, AlN films were grown using gallium (Ga) as surfactant on 4° off-axis 4H-SiC substrates via microwave plasma chemical vapor deposition (MPCVD). We have found that AlN growth rate can be greatly improved due to the catalytic effect of trimethyl-gallium (TMGa), but AlN crystal structure and composition are not affected. When the proportion of TMGa in gas phase was low, crystal quality of AlN can be improved and three-dimensional growth mode of AlN was enhanced with the increase of Ga source. When the proportion of TMGa in gas phase was high, two-dimensional growth mode of AlN was presented, with the increase of Ga source results in the deterioration of AlN crystal quality. Finally, employing a two-step growth approach, involving the initial growth of Ga-free AlN nucleation layer followed by Ga-assisted AlN growth, high quality of AlN film with flat surface was obtained and the full width at half maximum (FWHM) values of 415 nm AlN (002) and (102) planes were 465 and 597 arcsec. 展开更多
关键词 AlN thin film MPCVD gallium surfactant nucleation layer LASER
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Armoring lithium metal anode with soft–rigid gradient interphase toward high-capacity and long-life all-solid-state battery
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作者 Rui Zhang Biao Chen +5 位作者 Yuhan Ma Yue Li Junwei Sha Liying Ma Chunsheng Shi Naiqin Zhao 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1279-1289,共11页
Solid polymer electrolytes(SPEs)are highly promising for realizing high-capacity,low-cost,and safe Li metal batteries.However,the Li dendritic growth and side reactions between Li and SPEs also plague these systems.He... Solid polymer electrolytes(SPEs)are highly promising for realizing high-capacity,low-cost,and safe Li metal batteries.However,the Li dendritic growth and side reactions between Li and SPEs also plague these systems.Herein,a fluorinated lithium salt coating(FC)with organic-inorganic gradient and soft–rigid feature is introduced on Li surface as an artificial protective layer by the in-situ reaction between Li metal and fluorinated carboxylic acid.The FC layer can improve the interface stability and wettability between Li and SPEs,assist the transport of Li ions,and guide Li nucleation,contributing to a dendrite-free Li deposition and long-lifespan Li metal batteries.The symmetric cell with FC-Li anodes exhibits a high areal capacity of 1 mAh cm^(-2)at 0.5 mA cm^(-2),and an ultra-long lifespan of 2000 h at a current density of 0.1 mA cm^(-2).Moreover,the full cell paired with the LiFePO4 cathode exhibits improved cycling stability,remaining 83.7%capacity after 500 cycles at 1 C.When matching with the S cathode,the FC layer can prevent the shuttle effect,contributing to stable and high-capacity Li–S battery.This work provided a promising way for the construction of stable all-solid-state lithium metal batteries with prolonged lifespan. 展开更多
关键词 All-solid-state battery Solid polymer electrolyte Li metal anode Li nucleation Interface stability
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Unlock the full potential of carbon cloth-based scaffolds towards magnesium metal storage via regulation on magnesiophilicity and surface geometric structure
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作者 Jing Liu Min Wang +4 位作者 Zhonghua Zhang Jinlei Zhang Yitao He Zhenfang Zhou Guicun Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期423-434,I0010,共13页
The development of rechargeable magnesium(Mg) batteries is of practical significance to upgrade the electric energy storage devices due to exceptional capacity and abundant resources of Mg-metal anode.However,the reve... The development of rechargeable magnesium(Mg) batteries is of practical significance to upgrade the electric energy storage devices due to exceptional capacity and abundant resources of Mg-metal anode.However,the reversible Mg electrochemistry suffers from unsatisfied rate capability and lifespan,mainly caused by non-uniform distribution of electrodeposits.In this work,a fresh design concept of threedimensional carbon cloths scaffolds is proposed to overcome the uncontrollable Mg growth via homogenizing electric field and improving magnesiophilicity.A microscopic smooth and nitrogen-containing defective carbonaceous layer is constructed through a facile pyrolysis of ZIF8 on carbon cloths.As revealed by finite element simulation and DFT calculation results,the smooth surface endows with uniform electric field distribution and simultaneously the nitrogen-doping species enable good magnesiophilicity of scaffolds.The fine and uniform Mg nucleus as well as the inner electrodeposit behavior are also disclosed.As a result,an exceptional cycle life of 500 cycles at 4.0 mA cm^(-2) and 4.0 mA h cm^(-2) is firstly realized to our best knowledge.Besides,the functional scaffolds can be cycled for over 2200 h at 2.0 mA cm^(-2) under a normalized capacity of 5.0 mA h cm^(-2),far exceeding previous results.This work offers an effective approach to enable the full potential of carbon cloths-based scaffolds towards metal storage for next generation battery applications. 展开更多
关键词 Magnesium metal anodes ELECTRODEPOSITION Heterogeneous nucleation
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Effect of addition temperature on dispersion behavior and grain refinement efficiency of MgO introduced into Mg alloy
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作者 Le ZAI Xin TONG +1 位作者 Yun WANG Xiao-huai XUE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2491-2506,共16页
The effect of addition temperature of MgO particles(MgOp)on their dispersion behavior and the efficiency of grain refinement in AZ31 Mg alloy was investigated.In addition,the grain refinement mechanism was systematica... The effect of addition temperature of MgO particles(MgOp)on their dispersion behavior and the efficiency of grain refinement in AZ31 Mg alloy was investigated.In addition,the grain refinement mechanism was systematically studied by microstructure characterization,thermodynamic calculation,and analysis of solidification curves.The results show that the grain size of AZ31 Mg alloy initially decreases and then increases as the MgOp addition temperature is increased from 720 to 810℃,exhibiting a minimum value of 136μm at 780℃.The improved grain refinement efficiency with increasing MgOp addition temperature can be attributed to the reduced Mg melt viscosity and enhanced wettability between MgOp and Mg melt.Furthermore,a corresponding physical model describing the solidification behavior and grain refinement mechanism was proposed. 展开更多
关键词 grain refinement MgO nucleation particles AZ31 alloy addition temperature dispersion behavior
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THE VARIABLE ROLE OF CLAY ON THE CRYSTALLIZATION BEHAVIOR OF DMDBS-NUCLEATED POLYPROPYLENE
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作者 王柯 傅强 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2011年第6期732-740,共9页
The effect of clay on the nucleating behavior of 1,3:2,4-bis(3,4-dimethylbenzylidene) sorbitol (DMDBS) in cryatallization of isotactic polypropylene (iPP) was investigated by means of differential scanning calo... The effect of clay on the nucleating behavior of 1,3:2,4-bis(3,4-dimethylbenzylidene) sorbitol (DMDBS) in cryatallization of isotactic polypropylene (iPP) was investigated by means of differential scanning calorimetry (DSC), dynamic rheology and polarized light microscopy (PLM). It is interesting to note that the incorporation of layered clay nanoparticles into DMDBS-nucleated iPP may induce a synergetic nucleation effect while the DMDBS content is below 0.1 wt%, otherwise it restricts the crystallization rate prominently as the DMDBS content increases up to 0.3 wt%, which has exceeded the content threshold to yield a nucleating agent (NA) network. As shown by dynamic rheological investigations, the clay nanoparticles demonstrate an obstructive effect of disturbing the consistency of DMDBS fibrils network. Moreover, to further demonstrate the importance of NA network formation in the crystallization of iPP, we used another NA named HPN-20e, which can not form network structure at all over the concentration studied, for comparison. In this case, the nucleated-crystallization rate is independent on the addition of clay nanoparticles, as the nucleating mechanism is an individual nuclei manner without NA network forming. 展开更多
关键词 DMDBS Nucleating agent network Clay nanoparticles nucleated-crystallization.
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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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EFFECT OF FINAL HEATING TEMPERATURE ON CRYSTALLIZATION OF ISOTACTIC POLYPROPYLENE NUCLEATED WITH AN ARYL AMIDE DERIVATIVE AS β-FORM NUCLEATING AGENT 被引量:4
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作者 于建 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2011年第3期308-317,共10页
An aryl dicarboxylic acid amide compound TMB-5 is an efficient β-form nucleating agent for isotactic polypropylene (iPP). Because of the solubility of TMB-5, superstructure and morphology of iPP crystals changed wi... An aryl dicarboxylic acid amide compound TMB-5 is an efficient β-form nucleating agent for isotactic polypropylene (iPP). Because of the solubility of TMB-5, superstructure and morphology of iPP crystals changed with melting conditions. Effects of final heating temperature (Tf) on heterogeneous nucleation of iPP/TMB-5 were investigated. It was discovered that the crystallization temperature increased with decreasing Tf value. The optical microscopic images indicated that when TMB-5 partially dissolved in iPP melt, the remaining (non-dissolved) TMB-5 facilitated the recrystallization of dissolved nucleating agent from the melt, which promoted crystallization. Complete solubility of nucleating agent caused the decreasing efficiency. TMB-5 recrystallized in the form of tiny needles, whose aggregates induced dendritic iPP crystals. 展开更多
关键词 Isotactic polypropylene Heterogeneous nucleation CRYSTALLIZATION Polymer processing Melting temperature.
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Vapor transport growth of MoS2 nucleated on SiO2 patterns and graphene flakes
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作者 Toma Stoica Mihai Stoica +5 位作者 Martial Duchamp Andreas Tiedemann Siegfried Mantl Detlev Orutzmacher Dan Buca Beata E. Kardynal 《Nano Research》 SCIE EI CAS CSCD 2016年第11期3504-3514,共11页
Vapor transport growth of atomically thin MoS2 layers on patterned substrates is investigated, as it is a step towards the self-aligned growth and formation of heterojunctions, which could be useful in future applicat... Vapor transport growth of atomically thin MoS2 layers on patterned substrates is investigated, as it is a step towards the self-aligned growth and formation of heterojunctions, which could be useful in future applications. Enhanced formation of MoS2 flakes at the pattern edges is observed on both the substrates examined, namely, patterned thermal SiO2 on Si(100) and graphene flakes on SiO2. The diffusion driven growth leads to the formation of MoS2 monolayers (MLs) with sizes of tens of micrometers around the edges of SiO2 patterns. The growth mode and the optical quality of the MoS2 flakes can be controlled by varying the substrate temperature. Besides the lateral growth, 3R-type pyramids are obtained on prolonging the growth. Lateral MoS2-graphene heterostructures are obtained by using graphene flakes on SiO2 as a substrate. 展开更多
关键词 MOS2 localized nucleation andgrowth GRAPHENE two-dimensional (2D)heterostructures
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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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