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Ligand effects on electronic and optoelectronic properties of two-dimensional PbS necking percolative superlattices
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作者 Man Zhao Defang Ding +5 位作者 Fangxu Yang Dawei Wang Jiawei Lv Wenping Hu Chenguang Lu Zhiyong Tang 《Nano Research》 SCIE EI CAS CSCD 2017年第4期1249-1257,共9页
The inter-nanocrystal (NC) distance, necking degree, ordering level, and NC surface ligands all affect the electronic and optoelectronic properties of NC solids. Herein, we introduce a unique PbS structure of neckin... The inter-nanocrystal (NC) distance, necking degree, ordering level, and NC surface ligands all affect the electronic and optoelectronic properties of NC solids. Herein, we introduce a unique PbS structure of necking percolative superlattices to exclude the morphological factors and study the effect of ligands on the NC properties. X-ray photoelectron spectroscopy data indicate that 1,2-ethanedithiol (EDT), oxalic acid, mercaptopropionic acid, and NH4SCN (SCN) ligands were attached to the surface of NCs by substrate-supported Iigand exchange. Field-effect transistors were tested and photodetector measurements were performed to compare these NC solids. An SCN-treated film had the highest mobility and responsivity under high-power intensity irradiation owing to its high carrier density, whereas an EDT-treated film had the lowest mobility, photocurrent, and dark current. These findings introduce new avenues for choosing suitable ligands for NC applications. 展开更多
关键词 NANOCRYSTALS necking percolative superlattices LIGAND mobility trap states
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Regulation mechanism of broadband weakly epsilon-negative response interpreted via Cu/CaCu_(3)Ti_(4)O_(12) metacomposites
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作者 Jing Mao Yun-Peng Qu +1 位作者 Yun-Lei Zhou Xiao-Si Qi 《Rare Metals》 2025年第10期7956-7963,共8页
Finely tuning spectral characteristics of the epsilon-negative(ε'<0,EN) response is full of challenges when its regulatory mechanism in metacomposites is not yet clear.Herein,we have meticulously designed Cu/C... Finely tuning spectral characteristics of the epsilon-negative(ε'<0,EN) response is full of challenges when its regulatory mechanism in metacomposites is not yet clear.Herein,we have meticulously designed Cu/CaCu_(3)Ti_(4)O_(12)(Cu/CCTO) percolative metacomposites,successfully achieved both epsilon-negative and ε'-near-zero(ENZ)responses in the radio-frequency band.Before percolation,a large number of electric dipoles in the metacomposites achieved resonance characteristics near the ENZ point under the excitation of radio frequency electromagnetic fields,and as the Cu content increased,the ENZ frequency varied from 942,858,862 to 632 MHz. 展开更多
关键词 metacomposites percolative metacompositessuccessfully percolative electric dipoles BROADBAND tuning spectral characteristics resonance characteristics weakly epsilon negative
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Zwitterionic Surfactant Modified Carbon Nanotubes Incorporated Percolative Polymer Composites with Improved Features
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作者 Farrukh Bashir Tajamal Hussain +6 位作者 Adnan Mujahid Ayesha Mushtaq Muhammad Aamir Raza Mirza Nadeem Ahmad Muhammad Zahid Muhammad Imran Din Huma Tareen 《Nano Biomedicine & Engineering》 2023年第2期136-149,共14页
Modification of carbon nanotubes (CNTs) and their incoporation in polymer matrix have attracted much attention of researchers. As maximum dispersion of CNTs could enhance the properties of matrix dynamically, research... Modification of carbon nanotubes (CNTs) and their incoporation in polymer matrix have attracted much attention of researchers. As maximum dispersion of CNTs could enhance the properties of matrix dynamically, researchers are trying to find new methodologies to obtain this target. However, maximum dispersion remains a great challenge and under the stage of progress. Here, we claimed the synthesis of composites with a highly uniform dispersion of the filler that results significantly improved electrical features. In this regard, composites of polymethylmethacrylate (PMMA) were fabricated by using pristine and zwitterionic surfactant (ZIS) modified CNTs (ZIS-CNTs). Characterization was done by using ultraviolet-visible (UV-Vis), Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermo gravimetric analysis (TGA) techniques. UV-Vis and FTIR spectroscopy confirmed the synthesis of ZIS-CNTs and composites. UV-Vis spectra showed an increase in wavelength with the decrease in optical band gap for CNTs-based (CNTs/PMMA) and ZIS-CNTs-based (ZIS-CNTs/PMMA) composites. SEM and XRD studies confirmed a significant homogenoeus and uniform dispersion of CNTs in ZIS- CNTs/PMMA composites. An increase in conductivity of PMMA from 10^(−9) to 10^(−2) and 10^(−1) S/cm was observed on addition of less than 1% (mass fraction) of CNTs without and with modification by ZIS, respectively. Low values of percolation threshold at 0.5% and 0.005% for CNTs/PMMA and ZIS- CNTs/PMMA composites were obtained, respectively. TGA analysis showed a slow rate of decomposition for composites than that for pure PMMA. Around 600 ℃, 3% CNTs/PMMA and 7% ZIS-CNTs/PMMA composites were left in the end, which depicts the increase in thermal stability of PMMA. This work depicts a better dispersion of CNTs in PMMA matrix via slight modification in synthesis as well as by using ZIS as surfactant. 展开更多
关键词 polymer composite enhanced dispersion of carbon nanotubes(CNTs) increased electrical conductivity low percolation threshold improved thermal stability
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Suppressing high voltage chemo-mechanical degradation in single crystal nickel-rich cathodes for high-performance all-solid-state lithium batteries 被引量:1
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作者 Yirong Xiao Le Yang +5 位作者 Chaoyuan Zeng Ze Hua Shuangquan Qu Niaz Ahmad Ruiwen Shao Wen Yang 《Journal of Energy Chemistry》 2025年第3期377-385,共9页
Sulfide-based all-solid-state lithium batteries suffer from electrochemo-mechanical damage to Ni-rich oxide-based cathode active materials(CAMs),primarily caused by severe volume changes,results in significant stress ... Sulfide-based all-solid-state lithium batteries suffer from electrochemo-mechanical damage to Ni-rich oxide-based cathode active materials(CAMs),primarily caused by severe volume changes,results in significant stress and strain,causes micro-cracks and interfacial contact loss at potentials>4.3 V(vs.Li/Li^(+)).Quantifying micro-cracks and voids in CAMs can reveal the degradation mechanisms of Ni-rich oxidebased cathodes during electrochemical cycling.Nonetheless,the origin of electrochemical-mechanical damage remains unclear.Herein,We have developed a multifunctional PEG-based soft buffer layer(SBL)on the surface of carbon black(CB).This layer functions as a percolation network in the single crystal LiNi_(0.83)Co_(0.07)Mn_(0.1)O_(2)and Li_(6)PS_(5)Cl composite cathode layer,ensuring superior ionic conductivity,reducing void formation and particle cracking,and promoting uniform utilization of the cathode active material in all-solid-state lithium batteries(ASSLBs).High-angle annular dark-field STEM combined with nanoscale X-ray holo-tomography and plasma-focused ion beam scanning electron microscopy confirmed that the PEG-based SBL mitigated strain induced by reaction heterogeneity in the cathode.This strain produces lattice stretches,distortions,and curved transition metal oxide layers near the surface,contributing to structural degradation at elevated voltages.Consequently,ASSLBs with a LiNi_(0.83)Co_(0.07)Mn_(0.1)O_(2)cathode containing LCCB-10(CB/PEG mass ratio:100/10)demonstrate a high areal capacity(2.53 mAh g^(-1)/0.32 mA g^(-1))and remarkable rate capability(0.58 mAh g^(-1)at 1.4 mA g^(-1)),with88%capacity retention over 1000 cycles. 展开更多
关键词 Single crystal nickel-rich oxide cathode Lattice stretches and distortions Reaction heterogeneity Percolation network All-solid-state lithium batteries
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不同富集法联合MALDI-TOF MS快速鉴定在血流感染中的应用评价 被引量:1
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作者 周丽雯 高向阳 +2 位作者 张渝 陈云丽 乔玉莉 《国际检验医学杂志》 2025年第11期1386-1390,共5页
目的比较不同细菌富集法联合基质辅助激光解吸电离时间飞行质谱(MALDI-TOF MS)快速鉴定血培养阳性瓶病原菌的效果,建立经济、有效、快速的前处理法。方法收集2024年1-6月普洱市人民医院检验科阳性报警血培养瓶共164份,经涂片镜检确认为... 目的比较不同细菌富集法联合基质辅助激光解吸电离时间飞行质谱(MALDI-TOF MS)快速鉴定血培养阳性瓶病原菌的效果,建立经济、有效、快速的前处理法。方法收集2024年1-6月普洱市人民医院检验科阳性报警血培养瓶共164份,经涂片镜检确认为单一菌阳性后分别采用分离胶促凝管法、十二烷基硫酸钠(SDS)法和Percoll细胞分离液密度梯度离心法(Percoll法)对阳性血培养样本进行细菌富集和纯化,并联合MALDI-TOF MS快速鉴定。以常规培养获得的纯菌落质谱结果为参考,比较分析3种细菌富集法快速鉴定结果的检出率和符合率。结果164份阳性血培养样本经常规培养鉴定单一菌包括革兰阴性菌65株、革兰阳性菌92株、真菌7株。分离胶促凝管法、SDS法和Percoll法3种方法对革兰阳性菌、革兰阴性菌、真菌的检出率差异无统计学意义(P>0.05)。分离胶促凝管法对革兰阴性菌的检出率高于革兰阳性菌,差异有统计学意义(P<0.05)。SDS法和Percoll法对革兰阳性菌、革兰阴性菌的检出率差异有统计学意义(P<0.05)。对于单一菌阳性瓶的快速鉴定,三种方法的检出率差异无统计学意义(P>0.05)。分离胶促凝管法、SDS法和Percoll法在>2.000鉴定分值下的符合率分别为45.73%、61.58%和64.02%,差异有统计学意义(χ^(2)=13.21,P<0.05)。结论分离胶促凝管法、SDS法及Percoll法联合MALDI-TOF MS直接鉴定阳性血培养瓶中的病原菌均具有较高的可行性和检出率。 展开更多
关键词 血培养 分离胶促凝管 十二烷基硫酸钠 PERCOLL 基质辅助激光解吸电离时间飞行质谱
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黄鳝生殖干细胞分离纯化与移植分析
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作者 张益民 罗婷婷 +1 位作者 詹圆圆 孙玉华 《大连海洋大学学报》 北大核心 2025年第5期771-779,共9页
为优化黄鳝(Monopterus albus)生殖干细胞(germline stem cells,GSCs)分离纯化方法及生殖干细胞同种移植程序,采用性腺体指数比较及组织学观察法对不同年龄黄鳝性腺进行分析,使用Percoll密度梯度离心法分离性腺细胞,通过流式细胞术、碱... 为优化黄鳝(Monopterus albus)生殖干细胞(germline stem cells,GSCs)分离纯化方法及生殖干细胞同种移植程序,采用性腺体指数比较及组织学观察法对不同年龄黄鳝性腺进行分析,使用Percoll密度梯度离心法分离性腺细胞,通过流式细胞术、碱性磷酸酶染色、干性基因差异表达分析等方法对黄鳝生殖干细胞进行鉴定,并进行生殖干细胞移植。结果表明:黄鳝生殖干细胞富集层为40%Percoll浓度层,占比达72.52%;自体移植最佳移植供体为1龄雌鱼,最佳移植受体为4~5龄雄鱼;白消安-高温联合处理法基本可以耗尽受体鱼内源性生殖细胞,之后移植的生殖干细胞可以在受体鱼体内定植并增殖,成功率达75%;Percoll密度梯度离心法可以在较短时间内分离纯化黄鳝生殖干细胞,获取的细胞可用于生殖干细胞移植,同种异体移植成功率较高,具有优秀的移植潜力。本研究可为黄鳝生殖干细胞同种移植体系的建立提供科学参考。 展开更多
关键词 黄鳝 Percoll密度梯度离心法 生殖干细胞 生殖干细胞移植
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Triadic percolation in computer virus spreading dynamics
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作者 Jie Gao Jianfeng Luo +3 位作者 Xing Li Yihong Li Zunguang Guo Xiaofeng Luo 《Chinese Physics B》 2025年第2期470-481,共12页
In recent years, the threats posed by computer viruses have become increasingly diverse and complex. While classic percolation theory provides a novel perspective for analyzing epidemics and information dissemination,... In recent years, the threats posed by computer viruses have become increasingly diverse and complex. While classic percolation theory provides a novel perspective for analyzing epidemics and information dissemination, it fails to capture the temporal dynamics of these systems and the effects of virus invasion and governmental regulation. Triadic percolation theory, a recent advancement, addresses these limitations. In this paper, we apply this new percolation mechanism to model the diffusion of computer viruses, deriving a precise mathematical formulation of the triadic percolation model and providing an analytical solution of the triadic percolation threshold. Additionally, we investigate the impact of nonlinear transmission probability characteristics on virus propagation. Numerical simulations demonstrate that reducing the network's average degree(or the positive regulation) or increasing regulatory interventions raises the outbreak threshold for computer viruses while decreasing their final size. Moreover, the study reveals that nonlinear transmission probabilities result in an increased number of solutions for the final size of the computer viruses. Our findings contribute new insights into controlling the spread of computer viruses. 展开更多
关键词 triadic percolation percolation threshold nonlinear transmission probability final size
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精子选择方法对牛精子质量及体外受精效果的影响
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作者 张楠 郭桃 +2 位作者 韩僖彤 张建军 张家新 《黑龙江动物繁殖》 2025年第1期24-30,36,共8页
为了探究不同精子选择方法对精子质量及体外受精(IVF)后胚胎发育的影响,试验以牛冷冻精液为研究对象,使用TALP液直接离心法(对照组)、TALP-Percoll-密度梯度离心法(1组)、TALP-PureSperm-密度梯度离心法(2组)处理牛冷冻精液,然后分别评... 为了探究不同精子选择方法对精子质量及体外受精(IVF)后胚胎发育的影响,试验以牛冷冻精液为研究对象,使用TALP液直接离心法(对照组)、TALP-Percoll-密度梯度离心法(1组)、TALP-PureSperm-密度梯度离心法(2组)处理牛冷冻精液,然后分别评价处理后精液的精子活力、运动参数[前向运动精子比例、平均路径速度(VAP)、直线运动速度(VSL)、曲线运动速度(VCL)、直线度(STR)、头部横向位移幅度(ALH)]、质膜完整率、顶体膜完整率、线粒体膜电位水平、活性氧(ROS)浓度、DNA完整性、获能精子率、顶体反应精子率、酪氨酸磷酸化水平,并比较精子IVF后胚胎发育情况(卵裂率、囊胚率)。结果表明:1组和2组的精子活力、前向运动精子比例、VAP、VSL、VCL、STR、ALH、精子质膜完整率、顶体反应精子率均显著高于对照组(P<0.05),精子DNA完整率高于对照组(P>0.05),精子ROS含量显著低于对照组(P<0.05),其中除ROS含量外,1组的其他指标均高于2组,其中精子活力差异显著(P<0.05),其他指标两组间差异不显著(P>0.05);1组和对照组的精子顶体完整率、精子酪氨酸磷酸化水平显著高于2组(P<0.05),1组和对照组间差异不显著(P>0.05);1组精子线粒体膜电位、获能精子率显著高于对照组和2组(P<0.05);1组卵裂率和囊胚率显著高于对照组(P<0.05),也高于2组,但差异不显著(P>0.05)。说明牛冷冻精液经TALP-Percoll-密度梯度离心法选择出的精子质量较优,且体外受精后胚胎发育效果更好,可作为牛IVF精子选择的首选方法。 展开更多
关键词 体外受精 精子选择 精子获能 PERCOLL PureSperm 胚胎发育
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Universality of percolation at dynamic pseudocritical point
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作者 Qiyuan Shi Shuo Wei +1 位作者 Youjin Deng Ming Li 《Chinese Physics B》 2025年第4期304-310,共7页
Universality,encompassing critical exponents,scaling functions,and dimensionless quantities,is fundamental to phase transition theory.In finite systems,universal behaviors are also expected to emerge at the pseudocrit... Universality,encompassing critical exponents,scaling functions,and dimensionless quantities,is fundamental to phase transition theory.In finite systems,universal behaviors are also expected to emerge at the pseudocritical point.Focusing on two-dimensional percolation,we show that the size distribution of the largest cluster asymptotically approaches to a Gumbel form in the subcritical phase,a Gaussian form in the supercritical phase,and transitions within the critical finite-size scaling window.Numerical results indicate that,at consistently defined pseudocritical points,this distribution exhibits a universal form across various lattices and percolation models(bond or site),within error bars,yet differs from the distribution at the critical point.The critical polynomial,universally zero for two-dimensional percolation at the critical point,becomes nonzero at pseudocritical points.Nevertheless,numerical evidence suggests that the critical polynomial,along with other dimensionless quantities such as wrapping probabilities and Binder cumulants,assumes fixed values at the pseudocritical point that are independent of the percolation type(bond or site)but vary with lattice structures.These findings imply that while strict universality breaks down at the pseudocritical point,certain extreme-value statistics and dimensionless quantities exhibit quasi-universality,revealing a subtle connection between scaling behaviors at critical and pseudocritical points. 展开更多
关键词 PERCOLATION UNIVERSALITY extreme-value statistics pseudocritical point
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Vital nodes identification method integrating degree centrality and cycle ratio
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作者 Yu Zhao Bo Yang 《Chinese Physics B》 2025年第3期45-62,共18页
Identifying vital nodes is one of the core issues of network science,and is crucial for epidemic prevention and control,network security maintenance,and biomedical research and development.In this paper,a new vital no... Identifying vital nodes is one of the core issues of network science,and is crucial for epidemic prevention and control,network security maintenance,and biomedical research and development.In this paper,a new vital nodes identification method,named degree and cycle ratio(DC),is proposed by integrating degree centrality(weightα)and cycle ratio(weight 1-α).The results show that the dynamic observations and weightαare nonlinear and non-monotonicity(i.e.,there exists an optimal valueα^(*)forα),and that DC performs better than a single index in most networks.According to the value ofα^(*),networks are classified into degree-dominant networks(α^(*)>0.5)and cycle-dominant networks(α^(*)<0.5).Specifically,in most degree-dominant networks(such as Chengdu-BUS,Chongqing-BUS and Beijing-BUS),degree is dominant in the identification of vital nodes,but the identification effect can be improved by adding cycle structure information to the nodes.In most cycle-dominant networks(such as Email,Wiki and Hamsterster),the cycle ratio is dominant in the identification of vital nodes,but the effect can be notably enhanced by additional node degree information.Finally,interestingly,in Lancichinetti-Fortunato-Radicchi(LFR)synthesis networks,the cycle-dominant network is observed. 展开更多
关键词 cycle ratio PERCOLATION epidemic spreading targeted immunization
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Laser-Induced Nanowire Percolation Interlocking for Ultrarobust Soft Electronics
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作者 Yeongju Jung Kyung Rok Pyun +8 位作者 Sejong Yu Jiyong Ahn Jinsol Kim Jung Jae Park Min Jae Lee Byunghong Lee Daeyeon Won Junhyuk Bang Seung Hwan Ko 《Nano-Micro Letters》 2025年第6期40-54,共15页
Metallic nanowires have served as novel materials for soft electronics due to their outstanding mechanical compliance and electrical properties.However,weak adhesion and low mechanical robustness of nanowire networks ... Metallic nanowires have served as novel materials for soft electronics due to their outstanding mechanical compliance and electrical properties.However,weak adhesion and low mechanical robustness of nanowire networks to substrates significantly undermine their reliability,necessitating the use of an insulating protective layer,which greatly limits their utility.Herein,we present a versatile and generalized laser-based process that simultaneously achieves strong adhesion and mechanical robustness of nanowire networks on diverse substrates without the need for a protective layer.In this method,the laser-induced photothermal energy at the interface between the nanowire network and the substrate facilitates the interpenetration of the nanowire network and the polymer matrix,resulting in mechanical interlocking through percolation.This mechanism is broadly applicable across different metallic nanowires and thermoplastic substrates,significantly enhancing its universality in diverse applications.Thereby,we demonstrated the mechanical robustness of nanowires in reusable wearable physiological sensors on the skin without compromising the performance of the sensor.Furthermore,enhanced robustness and electrical conductivity by the laser-induced interlocking enables a stable functionalization of conducting polymers in a wet environment,broadening its application into various electrochemical devices. 展开更多
关键词 Nanowire percolation network Laser processing Mechanical interlocking FUNCTIONALIZATION Conducting polymer
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Stable chromium isotope fractionation during melt percolation:Implications for chromium isotopic heterogeneity in the mantle
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作者 Haibo Ma Li-Juan Xu +5 位作者 Yu-Wen Su Chunyang Liu Sheng-Ao Liu Jia Liu Zezhou Wang Guochun Zhao 《Geoscience Frontiers》 2025年第4期41-55,共15页
To investigate the stable chromium(Cr)isotope variations during melt percolation in the mantle,we ana-lyzed the Cr isotopic compositions of fresh ultramafic rocks from the Balmuccia and Baldissero peridotite massifs l... To investigate the stable chromium(Cr)isotope variations during melt percolation in the mantle,we ana-lyzed the Cr isotopic compositions of fresh ultramafic rocks from the Balmuccia and Baldissero peridotite massifs located in the Italian Alps.These massifs represent fragments of the subcontinental lithospheric mantle.The samples collected included lherzolites,harzburgites,dunites,and pyroxenites.Lherzolites,formed through 5%-15%fractional melting of a primitive mantle source,exhibited δ^(53)Crvalues ranging from−0.13‰±0.03‰to−0.03‰±0.03‰.These values correlated negatively with Al_(2)O_(3)content,sug-gesting that partial melting induces Cr isotopic fractionation between the melts and residual peridotites.Harzburgites and dunites,influenced by the silicate melt percolation,displayed distinctδ^(53)Cr values.Notably,dunites not spatially associated with the pyroxenite veins exhibited slightly elevatedδ^(53)Cr val-ues(−0.05‰±0.03‰to 0.10‰±0.03‰)relative to lherzolites.This difference likely resulted from pyroxene dissolution and olivine precipitation during melt percolation processes.However,one dunite sample in direct contact with pyroxenite veins showed lowerδ^(53)Cr values(−0.26‰±0.03‰),possibly owing to the kinetic effects during silicate melt percolation.Pyroxenites are formed through the interac-tion of basaltic melts with the surrounding peridotite via a metasomatic reaction or crystallization in a vein.Most of theirδ^(53)Cr values(−0.26‰±0.03‰to−0.13‰±0.03‰)are positively correlated with MgO contents,suggesting that they were influenced by magmatic differentiation.However,two subsam-ples from a single clinopyroxenite vein exhibit anomalously lowδ^(53)Crvalues(−0.30‰±0.03‰and−0.43‰±0.03‰),which are attributed to kinetic isotopic fractionation during melt-percolation pro-cesses.Our findings suggest that melt percolation processes in the mantle contribute to the Cr isotopic heterogeneity observed within the Earth’s mantle. 展开更多
关键词 Cr isotopes Ultramafic rocks Peridotite massifs Melt percolation
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Graph neural networks unveil universal dynamics in directed percolation
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作者 Ji-Hui Han Cheng-Yi Zhang +3 位作者 Gao-Gao Dong Yue-Feng Shi Long-Feng Zhao Yi-Jiang Zou 《Chinese Physics B》 2025年第8期540-545,共6页
Recent advances in statistical physics highlight the significant potential of machine learning for phase transition recognition.This study introduces a deep learning framework based on graph neural network to investig... Recent advances in statistical physics highlight the significant potential of machine learning for phase transition recognition.This study introduces a deep learning framework based on graph neural network to investigate non-equilibrium phase transitions,specifically focusing on the directed percolation process.By converting lattices with varying dimensions and connectivity schemes into graph structures and embedding the temporal evolution of the percolation process into node features,our approach enables unified analysis across diverse systems.The framework utilizes a multi-layer graph attention mechanism combined with global pooling to autonomously extract critical features from local dynamics to global phase transition signatures.The model successfully predicts percolation thresholds without relying on lattice geometry,demonstrating its robustness and versatility.Our approach not only offers new insights into phase transition studies but also provides a powerful tool for analyzing complex dynamical systems across various domains. 展开更多
关键词 graph neural networks non-equilibrium phase transition directed percolation model nonlinear dynamics
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Swelling inhibition and percolation promotion of PQ-10 on weathered crust elution-deposited rare earth ores
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作者 Aoyang Sha Huifang Yang +6 位作者 Meiling Jiang Zhengyan He Zhenhu Liu Zhigao Xu Yaguang Du Ming Wu Ru'an Chi 《Journal of Rare Earths》 2025年第7期1559-1570,共12页
Weathered crust elution-deposited rare earth ores(WREOs)are rich in medium and heavy rare earth.In order to improve the in-situ leaching process,which is prone to landslides and poor permeability,cationic hydroxyethyl... Weathered crust elution-deposited rare earth ores(WREOs)are rich in medium and heavy rare earth.In order to improve the in-situ leaching process,which is prone to landslides and poor permeability,cationic hydroxyethyl cellulose(PQ-10)was used as a novel green swelling inhibitor and percolation promoter and was mixed with conventional leaching agent ammonium sulfate((NH_(4))_(2)SO_(4))to form a composite leaching agent to study the performance and mechanism of swelling inhibition and percolation promotion.Adding PQ-10 can inhibit the hydration swelling of WREOs,promote the percolation effect of the leaching agent,improve the rare earth(RE)leaching efficiency,and reduce the im purity aluminum(Al)leaching efficiency.Compared with the conventional leaching agent 2 wt%(NH_(4))_(2)SO_(4),the percolation time is reduced by 50%by using the composite leaching agent(0.02 wt%PQ-10+2 wt%(NH_(4))_(2)SO_(4)).PQ-10 has positively charged quaternary ammonium groups and hydrophilic group hydroxyl groups,which makes it easy to adsorb on WREOs multiple sites through electrostatic interaction and hydrogen bonding,weakening the electrostatic repulsion between mineral particles,reducing the WREOs interlayer spacing,compressing the double electric layer thickness at the solid-liquid interface,weakening the mineral hydration swelling and increasing the percolation rate.The long carbon chains of the polymer entangle and link the fine mineral particles to agglomerate them,increasing their particle size and reduc ing their hydration dispersion,and preventing blockage of the pe rcolation pores caused by migration of the fine particles through the ore body with the solution.PQ-10 molecules also insert the mine ral interlayer and expulsion of the internal water,further inhibiting the swelling of WREOs.Adding PQ-10 reduces the surface tension of(NH_(4))_(2)SO_(4)solution,improving the spreading and spreading ability of the solution,reducing the adhesion work between molecules in the solid-liquid phase and the adhesion work reduction factor.It proves that PQ-10 promotes the percolation effect of the leaching process of WREOs.In addition,PQ-10 expands the leaching pore size and seepage channels,further improving the percolation rate. 展开更多
关键词 Weathered crust elution-deposited rare earth ores Swelling inhibition Percolation promotion Rare earth leaching Composite leaching agent
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Thermal and Electrical Percolation Transport Behavior in Composite Materials with Oriented Binary Fillers
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作者 Jinxin Zhong Zhuoyu Wang +3 位作者 Xiaokun Gu Jun Wang Yuanyuan Wang Xin Qian 《Chinese Physics Letters》 2025年第8期83-96,共14页
In integrated circuit packaging,thermal interface materials(TIMs)must exhibit high thermal conductivity and electrical resistivity to prevent short circuits,enhance reliability,and ensure safety in high-voltage applic... In integrated circuit packaging,thermal interface materials(TIMs)must exhibit high thermal conductivity and electrical resistivity to prevent short circuits,enhance reliability,and ensure safety in high-voltage applications.We proposed the thermal-percolation electrical-resistive TIM incorporating binary fillers of both insulating and metallic nanowires with an orientation in the insulating polymer matrix.High thermal conductivity can be achieved through thermal percolation,while electrical non-conductivity is preserved by carefully controlling the electrical percolation threshold through metallic nanowire orientation.The electrical conductivity of the composite can be further regulated by adjusting the orientation and aspect ratio of the metallic fillers.A thermal conductivity of 10 W·m^(-1)·K^(-1)is achieved,with electrical non-conductive behavior preserved.This approach offers a pathway to realizing“thermal-percolation electrical-resistive”in hybrid TIMs,providing a strategic framework for designing high-performance TIMs. 展开更多
关键词 insulating polymer matrixhigh thermal conductivity electrical resistive integrated circuit packagingthermal interface materials tims must composite materials binary fillers metallic nanowires thermal percolationwhile thermal percolation
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1层和2层梯度离心法分离精子的效果评价 被引量:11
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作者 周其赵 冯春琼 +5 位作者 邹亚光 舒文 李铁求 李飞 刘存东 毛向明 《中华男科学杂志》 CAS CSCD 北大核心 2010年第3期217-219,共3页
目的:评价1层和2层Percoll密度梯度离心法分离精子的效果。方法:20份精液标本分别行50%1层,90%和45%Percoll2层密度梯度离心分离,处理前后应用SCA(sperm class analyzer)精子质量分析仪分析精子密度、活力和圆形细胞密度。结果:1层法分... 目的:评价1层和2层Percoll密度梯度离心法分离精子的效果。方法:20份精液标本分别行50%1层,90%和45%Percoll2层密度梯度离心分离,处理前后应用SCA(sperm class analyzer)精子质量分析仪分析精子密度、活力和圆形细胞密度。结果:1层法分离后精子回收率为(65.5±12.8)%,明显高于2层法(P<0.01);1层和2层法分离后a级精子百分率明显高于处理前(P<0.05,P<0.01),而1层法分离后a级精子百分率明显低于2层法(P<0.05);1层法分离精子后c级精子百分率明显高于2层法(P<0.05),与处理前相比没有明显差异(P>0.05);2层法分离后a+b级精子百分率明显高于处理前(P<0.05),1层法分离后a+b级精子百分率与处理前相比没有明显差异(P>0.05);1层和2层法分离后圆形细胞密度明显低于处理前(P<0.05,P<0.01),两种方法之间没有差异(P>0.05)。结论:1层法分离后精子回收率较高,精子的活力改变不大;2层法分离后精子回收率较低,精子的活力明显改善;1层和2层法都可以较好地把精子与圆形细胞分开。两种方法各有优势,在精子体外处理中都有着重要的应用价值。 展开更多
关键词 精子 PERCOLL 密度梯度离心 圆形细胞
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成人睾丸间质细胞的培养和鉴定 被引量:15
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作者 孙祥宙 邓春华 +1 位作者 郭海彬 刘建中 《中华男科学杂志》 CAS CSCD 2005年第5期356-358,共3页
目的寻求一种有效的体外分离、纯化成人睾丸间质细胞的方法。方法利用4个梯度(60%、34%、26%、21%)的Percoll液分离、纯化成人睾丸间质细胞。对分离的细胞进行细胞学观察、锥虫蓝染色、3β羟基类固醇脱氢酶(3βHSD)染色、分泌睾酮能力... 目的寻求一种有效的体外分离、纯化成人睾丸间质细胞的方法。方法利用4个梯度(60%、34%、26%、21%)的Percoll液分离、纯化成人睾丸间质细胞。对分离的细胞进行细胞学观察、锥虫蓝染色、3β羟基类固醇脱氢酶(3βHSD)染色、分泌睾酮能力和绒毛膜促性腺激素(hCG)对分离睾丸间质细胞的作用等检测。结果通过该方法能够获得高纯度(>90%)的成人睾丸间质细胞,并通过上述实验检测证实分离、纯化的睾丸间质细胞有良好的分泌睾酮能力。结论采用该方法对成人睾丸间质细胞进行初步的分离和纯化是简单有效的。 展开更多
关键词 睾丸间质细胞 Percoll液 分离 纯化 成年人
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大鼠睾丸间质细胞的原代培养、鉴定与功能监测 被引量:15
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作者 应锋 龚昳 +2 位作者 孙佳音 沈洁 韩晓冬 《中华男科学杂志》 CAS CSCD 2008年第1期7-10,共4页
目的:采用改良方法对大鼠睾丸间质细胞进行分离、纯化和原代培养,以得到更高纯度和稳定的间质细胞原代培养体系。方法:采用酶消化法分离大鼠睾丸间质细胞,再用Percoll连续密度梯度离心除去生精细胞、支持细胞等杂细胞,实现进一步纯化;用... 目的:采用改良方法对大鼠睾丸间质细胞进行分离、纯化和原代培养,以得到更高纯度和稳定的间质细胞原代培养体系。方法:采用酶消化法分离大鼠睾丸间质细胞,再用Percoll连续密度梯度离心除去生精细胞、支持细胞等杂细胞,实现进一步纯化;用3β-HSD特异性染色法鉴定间质细胞,同时采用放射免疫法测定间质细胞睾酮分泌活性。结果:培养的间质细胞纯度达到95%以上,每个睾丸可获取间质细胞约1×106个;通过3β-HSD特异性染色鉴定,该间质细胞胞质呈蓝黑色,而且细胞具有分泌睾酮的活性。结论:酶消化后以Percoll连续密度梯度离心可分离得到高纯度且具有睾酮分泌活性的间质细胞,操作简单易行,实验方法稳定。 展开更多
关键词 间质细胞 Percoll密度梯度离心 原代培养 3β-HSD染色 大鼠
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Percoll法处理牛精子对体外受精胚胎发育的影响 被引量:13
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作者 陈善军 梁冠生 +3 位作者 张嘉保 王艳军 关宏 刘健 《中国兽医学报》 CAS CSCD 北大核心 1998年第4期394-397,共4页
牛冷冻精液解冻后,在Percol梯度液中400g离心24min,有效地获得了57.87%±8.0%的精子回收率;对照组上游法精子回收率仅为15.87%±1.9%(P<0.05)。Percol和上游2种方法分离... 牛冷冻精液解冻后,在Percol梯度液中400g离心24min,有效地获得了57.87%±8.0%的精子回收率;对照组上游法精子回收率仅为15.87%±1.9%(P<0.05)。Percol和上游2种方法分离的精子在受精液中8、18h后的活率,分别为60%、10%和70%、20%。2种浓度Percol法分离的精子对不同成熟处理的卵母细胞体外受精(IVF)卵裂率的影响:精子最终浓度为2×106/mL时,成熟组Ⅰ(LH+FSH)和成熟组Ⅱ(PMSG+hCG)的卵裂率分别为56.19%和58.16%;精子最终浓度为5×106/mL时,2组的卵裂率分别为59.30%和62.77%,卵裂率在精子浓度不同组间及添加不同激素组间的差异不显著。本试验还研究了2种方法处理的精子对不同成熟处理组的卵裂率和囊胚率,用Percol法处理的精子(2×106/mL)在成熟组Ⅰ获得了57.16%的卵裂率和25.58%的囊胚率,而上游法分别为61.95%和19.02%,2种方法相差不显著(P>0.05);在成熟组Ⅱ获得了62.18%的卵裂率和24.77%的囊胚率,而上游法分别为71.18%和20.96%,2种方法的卵裂率相差显著(P<0.? 展开更多
关键词 Percoll法 冷冻精子 体外受精 胚胎
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采用Percoll法分离、纯化鲫肝细胞 被引量:6
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作者 张高峰 郭彤 +1 位作者 魏华 马珂 《中国水产科学》 CAS CSCD 北大核心 2007年第2期208-214,共7页
以Ⅳ型胶原酶消化法分离鲫(Carassius auratus)肝细胞,然后将其分成2组,一组不再经过进一步处理(即对照组);另一组再用Percoll液密度梯度离心纯化肝细胞(即实验组),然后将2组细胞接种于DMEM/F12培养基中培养10 d。在倒置显微镜下观察2... 以Ⅳ型胶原酶消化法分离鲫(Carassius auratus)肝细胞,然后将其分成2组,一组不再经过进一步处理(即对照组);另一组再用Percoll液密度梯度离心纯化肝细胞(即实验组),然后将2组细胞接种于DMEM/F12培养基中培养10 d。在倒置显微镜下观察2组肝细胞的形态并绘制细胞生长曲线;采用台盼蓝染色法比较2组肝细胞的存活率;通过HE染色法在光镜下检测肝细胞的纯度;采用MTT比色法测定2组肝细胞的增殖率;收集肝细胞培养上清液检测白蛋白、尿素以及乳酸脱氢酶的水平以检测2组肝细胞功能。结果表明,对照组鲫肝细胞存活率为80.6%,纯度为83.2%;实验组肝细胞存活率和纯度明显高于对照组(P<0.05),分别为94.2%和95.1%。实验中发现,从开始接种到大部分肝细胞贴壁生长,实验组比对照组肝细胞的增殖明显加快(P<0.05)。白蛋白分泌功能、尿素合成能力及乳酸脱氢酶检测结果表明,实验组培养上清液中白蛋白分泌量、尿素合成能力明显高于对照组(P<0.05);而乳酸脱氢酶含量明显低于对照组(P<0.05)。结论认为,用Percoll梯度液分离纯化肝细胞,可提高肝实质细胞纯度和活力,适合体外原代培养。 展开更多
关键词 肝细胞 分离 纯化 Percoll法
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