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Fine-mapping of a candidate gene for web blotch resistance in Arachis hypogaea L.
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作者 Xiaohui Wu Mengyuan Zhang +11 位作者 Zheng Zheng Ziqi Sun Feiyan Qi Hua liu Juan Wang Mengmeng Wang Ruifang Zhao Yue Wu Xiao Wang hongfei liu Wenzhao Dong Xinyou Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1494-1506,共13页
Peanut(Arachis hypogaea L.)is a globally important oil crop.Web blotch is one of the most important foliar diseases affecting peanut,which results in serious yield losses worldwide.Breeding web blotch-resistant peanut... Peanut(Arachis hypogaea L.)is a globally important oil crop.Web blotch is one of the most important foliar diseases affecting peanut,which results in serious yield losses worldwide.Breeding web blotch-resistant peanut varieties is the most effective and economically viable method for minimizing yield losses due to web blotch.In the current study,a bulked segregant analysis with next-generation sequencing was used to analyze an F2:3 segregating population and identify candidate loci related to web blotch resistance.Based on the fine-mapping of the candidate genomic interval using kompetitive allele-specific PCR(KASP)markers,we identified a novel web blotch resistance-related locus spanning approximately 169 kb on chromosome 16.This region included four annotated genes,of which only Arahy.35VVQ3 had a non-synonymous single nucleotide polymorphism in the coding region between the two parents.Two markers(Chr.16.12872635 and Chr.16.12966357)linked to this gene were shown to be co-segregated with the resistance of peanut web blotch by 72 randomly selected recombinant inbred lines(RIL),which could be used in marker-assisted breeding of resistant peanut varieties. 展开更多
关键词 peanut web blotch bulked segregant analysis KAsP markers resistant gene
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An unusual network of α-MnO_(2) nanowires with structure-induced hydrophilicity and conductivity for improved electrocatalysis 被引量:5
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作者 Yingdong Chen Shujiao Yang +2 位作者 hongfei liu Wei Zhang Rui Cao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第10期1724-1731,共8页
Nanowires with anisotropic morphologies have been applied in various scientific and technological areas.It is also widely employed to fabricate nanowires into high-dimensional superstructures(arrays,networks etc.)to o... Nanowires with anisotropic morphologies have been applied in various scientific and technological areas.It is also widely employed to fabricate nanowires into high-dimensional superstructures(arrays,networks etc.)to overcome the shortcomings of low-dimensional nanowires.However,typical strategies for constructing these superstructures are restricted to complicated and harsh synthetic conditions,not to mention unique 3D structures with advanced properties beyond common superstructures.Herein,we report an unusual network ofα-MnO_(2)nanowires with structure-induced hydrophilicity and conductivity.In the network,the nanowires are interconnected from all directions by nodes,and the 3D network structure is formed from the endless connection of nodes in a node-by-node way.The unique network structure brings about high hydrophilicity and conductivity,both of which are positive factors for an efficient electrocatalyst.Accordingly,the α-MnO_(2) network was tested for electrocatalytic water oxidation and showed significantly enhanced activity compared with isolatedα-MnO_(2)nanowires and 3Dα-MnO_(2)microspheres.This study not only provides a synthetic route toward an advanced network structure but also a new idea for the design of materials for electrochemistry with both efficient mass diffusion and charge transfer. 展开更多
关键词 ELECTROCATALYSIS Water oxidation Oxygen evolution reaction MnO_(2)network HYDROPHILICITY CONDUCTIVITY
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Wax from Pyrolysis of Waste Plastics as a Potential Source of Phase Change Material for Thermal Energy Storage 被引量:2
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作者 Pin Jin Ong Zhi Xiong Jerry Heng +11 位作者 Zhenxiang Xing Hnin Yu Yu Ko Pei Wang hongfei liu Rong Ji Xizu Wang Beng Hoon Tan Zibiao Li Jian Wei Xu Xian Jun Loh Enyi Ye Qiang Zhu 《Transactions of Tianjin University》 EI CAS 2023年第3期225-234,共10页
Over the past half-century, plastic consumption has grown rapidly due to its versatility, low cost, and unrivaled functional properties. Among the diff erent implemented strategies for recycling waste plastics, pyroly... Over the past half-century, plastic consumption has grown rapidly due to its versatility, low cost, and unrivaled functional properties. Among the diff erent implemented strategies for recycling waste plastics, pyrolysis is deemed the most economical option. Currently, the wax obtained from the pyrolysis of waste plastics is mainly used as a feedstock to manufacture chemicals and fuels or added to asphalt for pavement construction, with no other applications of wax being reported. Herein, the thermal pyrolysis of three common waste polyolefin plastics: high-density polyethylene(HDPE), low-density polyethylene(LDPE), and polypropylene(PP), was conducted at 450 ℃. The waste plastics-derived waxes were characterized and studied for a potential new application: phase change materials(PCMs) for thermal energy storage(TES). Gas chromatography–mass spectrometry analysis showed that paraffin makes up most of the composition of HDPE and LDPE waxes, whereas PP wax contains a mixture of naphthene, isoparaffin, olefin, and paraffin. Diff erential scanning calorimetry(DSC) analysis indicated that HDPE and LDPE waxes have a peak melting temperature of 33.8 ℃ and 40.3 ℃, with a relatively high latent heat of 103.2 J/g and 88.3 J/g, respectively, whereas the PP wax was found to have almost negligible latent heat. Fourier transform infrared spectroscopy and DSC results revealed good chemical and thermal stability of HDPE and LDPE waxes after 100 cycles of thermal cycling. Performance evaluation of the waxes was also conducted using a thermal storage pad to understand their thermoregulation characteristics for TES applications. 展开更多
关键词 PYROLYSIS Waste plastics RECYCLING WAX Phase change materials
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Cellular and molecular characteristics of the premetastatic niches 被引量:1
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作者 hongfei liu Guoxin Zhang Ran Gao 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第5期399-408,共10页
The premetastatic niches(PMN)formed by primary tumor-derived molecules regulate distant organs and tissues to further favor tumor colonization.Targeted PMN therapy may prevent tumor metastasis in the early stages,whic... The premetastatic niches(PMN)formed by primary tumor-derived molecules regulate distant organs and tissues to further favor tumor colonization.Targeted PMN therapy may prevent tumor metastasis in the early stages,which is becoming increasingly important.At present,there is a lack of in-depth understanding of the cellular and molecular characteristics of the PMN.Here,we summarize current research advances on the cellular and molecular characteristics of the PMN.We emphasize that PMN intervention is a potential therapeutic strategy for early prevention of tumor metastasis,which provides a promising basis for future research and clinical application. 展开更多
关键词 extracellular vesicles IMMUNOSUPPRESSION premetastatic niches tumor metastasis
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Preparation and Characterization of Nucleus/Shell TiO_2/HAP Complex Nanophotocatalyst 被引量:1
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作者 hongfei liu Xiaonong CHENG +2 位作者 Juan YANG Xuehua YAN Hebin SHI 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2007年第1期123-126,共4页
A rapid and more efficient method was developed to prepare nucleus/shell titania/hydroxyapatite (TiO2/HAP) complex nanophotocatalyst. Hydroxyapatite (5 μm) which had been dissolved with 0.1 mol/L HCI was formed o... A rapid and more efficient method was developed to prepare nucleus/shell titania/hydroxyapatite (TiO2/HAP) complex nanophotocatalyst. Hydroxyapatite (5 μm) which had been dissolved with 0.1 mol/L HCI was formed on the surface of the nanosized anatase titania powders by increasing the pH value of the solution at 90℃ in the water bath for only several hours .The microstructure and morphology of the resulting sample were investigated by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive spectrum (EDS) and atomic force microscope (AFM). The results indicated that nucleus/shell structural TiO2/HAP was formed in our experiments, and the thickness of the coating layer was about 5 nm. Photocatalytic decomposition of methyl orange was utilized to test the photocatalysis of the resulting samples and the result was compared with that of pure anatase titania powders (about 20 nm). It was shown that the photocatalytic activity of the sample was not decreased due to the coating of HAP. 展开更多
关键词 TiO2/HAP Nucleus/Shell structure PHOTOCATALYSIS
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Investigation of Lushan earthquake ionosphere VTEC anomalies based on GPS data 被引量:1
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作者 Weiping Jiang Yifang Ma +2 位作者 hongfei liu Liansheng Deng Xiaohui Zhou 《Earthquake Science》 2013年第3期259-265,共7页
Vertical total electron content (VTEC) time series were obtained from 22 GPS stations near the epicenter of the Lushan earthquake. In this paper, we have adopted a sliding average method to detect and analyze anomal... Vertical total electron content (VTEC) time series were obtained from 22 GPS stations near the epicenter of the Lushan earthquake. In this paper, we have adopted a sliding average method to detect and analyze anomalous VTEC associated with the earthquake. The results show that signif- icant, negative ionosphere VTEC anomalies appeared over the 5 days before the earthquake, and on the day when earthquake occurred. The maximum value of VTEC anoma- lies that exceeded the lower bound reached 20 TECU. The spatial distribution of VTEC anomalies showed a conjugate structure, which shifted to the magnetic equator, and subse- quently moved westwards. 展开更多
关键词 Lushan earthquake Vertical totalelectron content (VTEC) Anomalous perturbationGPS
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Downregulation of HNRNPK in human cancer cells inhibits lung metastasis 被引量:2
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作者 Mengyuan Li Wenlong Zhang +6 位作者 Xingjiu Yang hongfei liu Lin Cao Weisha Li Le Wang Guoxin Zhang Ran Gao 《Animal Models and Experimental Medicine》 CSCD 2019年第4期291-296,共6页
Background: Lung cancer frequently occurs in the clinic, leading to poor prognosis and high mortality. Markers for early diagnosis of lung cancer are scarce, and further potential therapeutic targets are also urgently... Background: Lung cancer frequently occurs in the clinic, leading to poor prognosis and high mortality. Markers for early diagnosis of lung cancer are scarce, and further potential therapeutic targets are also urgently needed.Method: We established a new mouse model in which the specific gene HNRNPK(heterogeneous nuclear ribonucleoprotein K) was downregulated after administration of doxycycline. The lung metastatic nodules were investigated using bioluminescence imaging, micro-CT, and autopsy quantification.Results: Compared with the short hairpin negative control group, less lung metastatic nodules were formed in the short hairpin RNA group.Conclusion: Downregulation of HNRNPK in cancer cells can inhibit lung metastasis. 展开更多
关键词 HNRNPK lung metastasis mouse model
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Estimation of Solar Observations with the Five-hundred-meter Aperture Spherical Radio Telescope(FAST)
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作者 Lei Qian Zhichen Pan +7 位作者 hongfei liu Hengqian Gan Jinglong Yu Lei Zhao Jiguang Lu Cun Sun Jingye Yan Peng Jiang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第1期1-3,共3页
We present the estimation of solar observation with the Five-hundred-meter Aperture Spherical radio Telescope(FAST).For both the quiet Sun and the Sun with radio bursts,when pointing directly to the Sun,the total powe... We present the estimation of solar observation with the Five-hundred-meter Aperture Spherical radio Telescope(FAST).For both the quiet Sun and the Sun with radio bursts,when pointing directly to the Sun,the total power received by FAST would be out of the safe operational range of the signal chain,even resulting in damage to the receiver.As a conclusion,the Sun should be kept at least~2°away from the main beam during observations at~1.25 GHz.The separation for lower frequency should be larger.For simplicity,the angular separation between the FAST beam and the Sun is suggested to be~5°for observations at 200 MHz or higher bands. 展开更多
关键词 Sun radio radiation-telescopes-techniques MISCELLANEOUS
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Synthesis of mesoporous sodium hyaluronate microspheres via electrostatic spray method
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作者 Wei Huang Jie Zhu +5 位作者 Yingshu Feng Dan Yang Caleb Kesse Firempong Yang Qu Haibing He hongfei liu 《Journal of Chinese Pharmaceutical Sciences》 CAS 2024年第11期985-1000,共16页
In the present study,we employed electrostatic spray technology to fabricate mesoporous microspheres containing sodium hyaluronate(SHMM).This approach aimed to overcome a significant challenge in the formulation devel... In the present study,we employed electrostatic spray technology to fabricate mesoporous microspheres containing sodium hyaluronate(SHMM).This approach aimed to overcome a significant challenge in the formulation development process,specifically addressing the limited water-locking ability inherent to the double-helix structure of sodium hyaluronate(SH).Various parameters were systematically investigated,including the solvent employed,concentrations of SH and poly(ethylene oxide),electrospray flow rate,voltage settings,and needle diameter.Through systematic single-factor testing,we identified the optimal formulation process for generating SH microspheres characterized by favorable morphology and particle size.Additionally,a similar single-factor examination focused on the concentration of the pore-forming agent and the drying temperature,leading to the successful production of mesoporous microspheres with discernible pores.The porosity of the three distinct batches of mesoporous microspheres was consistently measured at 20.30%±1.51%.Moreover,all these microspheres displayed a negative surface potential when suspended in water,affirming their strong capacity to bind with positively charged protein drugs.These findings underscored the feasibility of drug loading through ion exchange in subsequent stages.Notably,the successful preparation of recombinant human interferonα-2b crosslinked mesoporous microspheres(rhIFNα-2b-SHCMM)was achieved,demonstrating both high entrapment efficiency and an enhanced drug loading capacity. 展开更多
关键词 Electrostatic spray Ion exchange technology Sodium hyaluronate mesoporous microspheres
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高分子类型MONOLITH材料的制备技术及其作为亲和色谱固定相用于分离生物大分子的应用
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作者 许颖 高婷婷 +3 位作者 王启晓 屈阳 刘宏飞 辛渊蓉 《化学进展》 SCIE CAS CSCD 北大核心 2018年第8期1112-1120,共9页
高分子类型MONOLITH材料(也称整体柱,连续床)是近些年来发展迅速的一种新型的以高分子为基质的整体型多孔材料,由于其内部独特的三维连续相互贯通的多孔结构,在诸多应用领域越来越受到研究者的关注,尤其被认为是分离过滤领域的一个历史... 高分子类型MONOLITH材料(也称整体柱,连续床)是近些年来发展迅速的一种新型的以高分子为基质的整体型多孔材料,由于其内部独特的三维连续相互贯通的多孔结构,在诸多应用领域越来越受到研究者的关注,尤其被认为是分离过滤领域的一个历史性突破。与硅基质MONOLITH材料相比,高分子类型的MONOLITH材料具有制备工艺简单、生物相容性好、化学稳定性高和表面化学性质易调控等特点,因此作为亲和色谱的固定相在生物大分子的分离分析上具有更大的优势。本综述重点总结了高分子类型MONOLITH材料的制备方法及其最新研究进展,并论述了近5年来其作为亲和色谱固定相用于分离生物大分子的应用进展。 展开更多
关键词 高分子类型MONOLITH材料 制备技术 亲和色谱 固定相 生物大分子
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Commissioning progress of the FAST 被引量:17
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作者 Peng Jiang YouLing Yue +15 位作者 HengQian Gan Rui Yao Hui Li GaoFeng Pan JingHai Sun DongJun Yu hongfei liu NingYu Tang Lei Qian JiGuang Lu Jun Yan Bo Peng ShuXin Zhang QiMing Wang Qi Li Di Li 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2019年第5期3-24,共22页
The Five-hundred-meter Aperture Spherical radio Telescope(FAST) was completed with its main structure installed on September 25, 2016, after which it entered the commissioning phase. This paper aims to introduce the c... The Five-hundred-meter Aperture Spherical radio Telescope(FAST) was completed with its main structure installed on September 25, 2016, after which it entered the commissioning phase. This paper aims to introduce the commissioning progress of the FAST over the past two years. To improve its operational reliability and ensure effective observation time, FAST has been equipped with a real-time information system for the active reflector system and hierarchical commissioning scheme for the feed support system, which ultimately achieves safe operation of the two systems. For meeting the high-performance indices, a highprecision measurement system was set up based on the effective control methods that were implemented for the active reflector system and feed support system. Since the commissioning of the FAST, a low-frequency ultra-wideband receiver and 19-beam1.05-1.45 GHz receiver have been mainly used. Telescope efficiency, pointing accuracy, and system noise temperature were completely tested and ultimately achieved the acceptance indices of the telescope. The FAST has been in the process of national acceptance preparations and has begun to search for pulsars. In the future, it will still strive to improve its capabilities and expand its application prospects. 展开更多
关键词 RADIO telescopes and INSTRUMENTATION astronomical OBSERVATIONS RADIO WAVE RECEIVERS algorithms and implementation control systems
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Enhanced performance of GaN nanobelt-based photodetectors by means of piezotronic effects 被引量:6
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作者 Ruomeng Yu Caofeng Pan +6 位作者 Youfan Hu Lin Li hongfei liu Wei liu Soojin Chua Dongzhi Chi Zhong Lin Wang 《Nano Research》 SCIE EI CAS CSCD 2013年第10期758-766,共9页
GaN ultraviolet (UV) photodetectors (PDs) have attracted tremendous attention due to their chemical stability in harsh environments. Although Schottky- contacted GaN-based UV PDs have been implemented with better ... GaN ultraviolet (UV) photodetectors (PDs) have attracted tremendous attention due to their chemical stability in harsh environments. Although Schottky- contacted GaN-based UV PDs have been implemented with better performance than that of ohmic contacts, it remains unknown how the barrier height at local Schottky contacts controls the sensors' performance. In this work, the piezotronic effect was employed to tune the Schottky barrier height (SBH) at local contacts and hence enhance the performances of Schottky-contacted metal-semiconductor- metal (MSM) structured GaN nanobelt (NB)-based PDs. In general, the response level of the PDs was obviously enhanced by the piezotronic effect when applying a strain on devices. The responsivity of the PD was increased by 18%, and the sensitivity was enhanced by from 22% to 31%, when illuminated by a 325 nm laser with light intensity ranging from 12 to 2 W/cm2. Carefully studying the mechanism using band structure diagrams reveals that the observed enhancement of the PD performance resulted from the change in SBH caused by external strain as well as light intensity. Using piezotronic effects thus provides a practical way to enhance the performance of PDs made not only of GaN, but also other wurtzite and zinc blende family materials. 展开更多
关键词 GaN nanobelts Schottky contact piezotronics PHOTODETECTOR
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鼓泡塔细胞反应器流体力学与传质特性
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作者 徐胜楠 刘宏斐 +2 位作者 李雪良 堵国成 陈坚 《过程工程学报》 CAS CSCD 北大核心 2022年第9期1192-1202,共11页
以超大规模细胞培养为目的,构建了与细胞培养体系十分接近的冷模实验体系,系统地研究了微载体(Cytodex I)、细胞保护剂(Pluronic F68)和消泡剂(Antifoam C)对鼓泡塔反应器中气、固、液三相流流体力学和氧传质特性的影响。在0.04~0.17 c... 以超大规模细胞培养为目的,构建了与细胞培养体系十分接近的冷模实验体系,系统地研究了微载体(Cytodex I)、细胞保护剂(Pluronic F68)和消泡剂(Antifoam C)对鼓泡塔反应器中气、固、液三相流流体力学和氧传质特性的影响。在0.04~0.17 cm/s表观气速范围内采用50μm孔径的烧结金属滤芯曝气时,在含有0.5和1.0 g/L的Pluronic F68的磷酸盐缓冲溶液冷模体系中,气含率与表观气速成线性增加关系,而气泡直径受表观气速影响较小;相同气速下的冷模体系与空气-水体系相比,气含率显著提高,气泡直径明显减小。在所研究的表观气速范围内微载体均可全悬浮,对气含率有一定增强,但微载体浓度为14%~20%时对气泡大小几乎无影响。消泡剂用量在1.60×10^(-4)时,可以有效抑制泡沫的形成。添加剂对液膜传质系数k_(L)有较大负面作用,抵消了小气泡带来的传质面积增加,总的体积传质系数k_(L)α变化不大。Euler-Euler多相流计算流体力学模型与拟稳态实验数据吻合较好,可用于指导反应器放大设计。 展开更多
关键词 鼓泡塔 微载体 细胞培养 气泡 气含率 传质 计算流体力学
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The first pulsar discovered by FAST 被引量:7
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作者 Lei Qian ZhiChen Pan +20 位作者 Di Li George Hobbs WeiWei Zhu Pei Wang ZhiJie liu YouLing Yue Yan Zhu hongfei liu DongJun Yu JingHai Sun Peng Jiang GaoFeng Pan Hui Li HengQian Gan Rui Yao XiaoYao Xie Fernando Camilo Andrew Cameron Lei Zhang Shen Wang FAST Collaboration 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2019年第5期71-74,共4页
To assist with the commissioning [1] of the Five-hundredmeter Aperture Spherical radio Telescope (FAST), we performed a pulsar search, with the primary goal of developing and testing the pulsar data acquisition and pr... To assist with the commissioning [1] of the Five-hundredmeter Aperture Spherical radio Telescope (FAST), we performed a pulsar search, with the primary goal of developing and testing the pulsar data acquisition and processing pipelines. We tested and used three pipelines, two (Pl and P2 hereafter) searched for the periodic signature of pulsars whereas the other one was used to search for bright single pulses (P3 hereafter). 展开更多
关键词 pulsar TELESCOPE
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Polyethylene glycol/polylactic acid block co‐polymers as solid–solid phase change materials 被引量:3
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作者 Xiang YDSoo Joseph K.Muiruri +11 位作者 Jayven CCYeo Zhuang MPng Anqi Sng Huiqing Xie Rong Ji Suxi Wang hongfei liu Jianwei Xu Xian JLoh Qingyu Yan Zibiao Li Qiang Zhu 《SmartMat》 2023年第3期108-119,共12页
Phase change materials(PCMs)are promising thermal energy storage materials due to their high specific latent heat.Conventional PCMs typically exploit the solid–liquid(s–l)transition.However,leakage and leaching are ... Phase change materials(PCMs)are promising thermal energy storage materials due to their high specific latent heat.Conventional PCMs typically exploit the solid–liquid(s–l)transition.However,leakage and leaching are common issues for solid–liquid PCMs,which have to be addressed before usage in practical applications.In contrast,solid–solid(s–s)PCMs would naturally overcome these issues due to their inherent form stability and homogeneity.In this study,we report a new type of s–s PCM based on chemically linked polyethylene glycol(PEG,the PCM portion)with polylactic acid(PLA,the support portion)in the form of a block co‐polymer.Solid‐solid latent heat of up to 56 J/g could be achieved,with melting points of between 44°C and 55°C.For comparison,PEG was physically mixed into a PLA matrix to form a PEG:PLA composite.However,the composite material saw leakage of up to 9%upon heating,with a corresponding loss in thermal storage capacity.In contrast,the mPEG/PLA block co‐polymers were found to be completely homogeneous and thermally stable even when heated above its phase transition temperature,with no observable leakage,demonstrating the superiority of chemical linking strategies in ensuring form stability. 展开更多
关键词 block co‐polymer chemically linked form‐stable phase change material(PCM) polyethylene glycol(PEG) polylactic acid(PLA) solid–solid transition
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Interfacial ion regulation on 2D layered double hydroxide nanosheets for enhanced thermal insulation 被引量:2
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作者 Chun Wang Hengyu Xu +10 位作者 Han Cheng Hao Yu Si liu Wenjie Wang Ruilin Yuan hongfei liu Tianpei Zhou Wangsheng Chu HengAn Wu Yi Xie Changzheng Wu 《Science China Chemistry》 SCIE EI CSCD 2022年第5期898-904,共7页
Exploring new strategies to broaden the upper/lower limit of thermal conductivity is of great interest to develop thermal management materials that can adapt to extreme environments.In this work,we employ an interfaci... Exploring new strategies to broaden the upper/lower limit of thermal conductivity is of great interest to develop thermal management materials that can adapt to extreme environments.In this work,we employ an interfacial ion regulation to enhance the thermal insulation performance of 2D layered double hydroxide nanosheets.The introduction of interfacial ion enlarges the interplanar spacing of Co(OH)_(2) nanosheets from 4.64 to 8.05 ?,which reduces phonon scattering length perpendicular to the two-dimensional plane and leads to enhanced interlayer thermal insulation.The interfacial ion-regulated Co(OH)_(2)(named as Co(OH)_(2)-M^(x-)) exhibits 3-fold enhancement of thermal insulation through decreasing the thermal conductivity to as low as 0.15 W m^(-1) K^(-1),which is among the top values in 2D solid materials.We anticipate that interfacial ion regulation for 2D nanosheets paves a new avenue to break through the thermal insulation limit. 展开更多
关键词 two dimensional materials interfacial ion regulation thermal conductivity phonon scattering
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Synthesis of mesoporous γ-AlOOH@Fe_3O_4 magnetic nanomicrospheres 被引量:4
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作者 Yuanyuan Zheng Shengfu Ji +2 位作者 hongfei liu Ming Li Hao Yang 《Particuology》 SCIE EI CAS CSCD 2012年第6期751-758,共8页
Mesoporous γ-AIOOH@Fe3O4 magnetic nanomicrospheres were synthesized using superparamagnetic Fe304 nanoparticles as the core and aluminum isopropoxide (ALP) as the aluminum source. The obtained magnetic nanomicrosph... Mesoporous γ-AIOOH@Fe3O4 magnetic nanomicrospheres were synthesized using superparamagnetic Fe304 nanoparticles as the core and aluminum isopropoxide (ALP) as the aluminum source. The obtained magnetic nanomicrospheres were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), N2 adsorption-desorption and vibrating sample magnetometry (VSM). The effects of preparation parameters such as hydrolysis time of AIP, concentration of AlP and coating layer number on microspheres were investigated. The results indicated that the mesoporous γ-AIOOH@Fe3O4 magnetic nanomicrospheres consisted of a mesoporous γ-AIOOH shell and a Fe3O4 magnetic core. The diameter of γ-AIOOH@Fe3O4 nanomicrospheres was about 200 nm, the thickness of mesoporous γ-AIOOH shell was about 5 nm and the average pore size was 3.8 nm. The thickness of the mesoporous γ-AIOOH shell could be controlled via layer-by-layer coating times. The formation mechanism of the mesoporous γ-AIOOH shell involved a "chemisorption-hydrolysis" process. 展开更多
关键词 Magnetic nanomicrospheres Fe3O4 γ-AIOOH shellMesoporousHydrolysis
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Status and perspectives of the CRAFTS extra-galactic HI survey
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作者 Kai Zhang JingWen Wu +16 位作者 Di Li Marko Krco Lister Staveley-Smith NingYu Tang Lei Qian MengTing liu ChengJin Jin YouLing Yue Yan Zhu hongfei liu DongJun Yu JingHai Sun GaoFeng Pan Hui Li HengQian Gan Rui Yao FAST Collaboration 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2019年第5期52-60,共9页
The Five-hundred-meter Aperture Spherical radio Telescope(FAST) is expected to complete its commissioning in 2019. FAST will soon begin the Commensal Radio Astronomy FasT Survey(CRAFTS), a novel and unprecedented comm... The Five-hundred-meter Aperture Spherical radio Telescope(FAST) is expected to complete its commissioning in 2019. FAST will soon begin the Commensal Radio Astronomy FasT Survey(CRAFTS), a novel and unprecedented commensal drift scan survey of the entire sky visible from FAST. The goal of CRAFTS is to cover more than 20000 deg2 and reach redshift up to about 0.35. We provide empirical measurements of the beam size and sensitivity of FAST across the 1.05 to 1.45 GHz frequency range of the FAST L-band array of 19-beams(FLAN). Using a simulated HI-galaxy catalogue based on the HI Mass Function(HIMF), we estimate the number of galaxies that CRAFTS may detect. At redshifts below 0.35, over 6 × 105 HI galaxies may be detected. Below the redshift of 0.07, the CRAFTS HIMF will be complete above a mass threshold of 109.5 M⊙. FAST will be able to investigate the environmental and redshift dependence of the HIMF to an unprecedented depth, shedding light onto the missing baryon and missing satellite problems. 展开更多
关键词 HI REGIONS and 21-cm lines radio telescopes and instrumentation statistical and correlative studies of properties
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Aqueous and mechanical exfoliation, unique properties, and theoretical understanding of MoO3 nanosheets made from free-standing a-MoO3 crystals: Raman mode softening and absorption edge blue shift
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作者 hongfei liu Yongqing Cai +5 位作者 Mingyong Han Shifeng Guo Ming Lin Meng Zhao Yongwei Zhang Dongzhi Chi 《Nano Research》 SCIE EI CAS CSCD 2018年第3期1193-1203,共11页
Crystalline α-MoO3 belts consisting of nanosheets stacked along their [010] axes were synthesized via thermal vapor transport of MoO3 powders at elevated temperatures. The MoO3 belts were millimeters in length along ... Crystalline α-MoO3 belts consisting of nanosheets stacked along their [010] axes were synthesized via thermal vapor transport of MoO3 powders at elevated temperatures. The MoO3 belts were millimeters in length along their [001] axes and tens to hundreds of micrometers in width along their [100] axes. Mechanical and aqueous exfoliations of the belts to form two-dimensional (2D) nanosheets were processed via the scotch-tape and bovine serum albumin (BSA) assisted methods, respectively. Upon scotch-tape exfoliation, the Raman features of MoO3 exhibited monotonic decreases in intensity as the thickness was gradually fell to approach that of a 2D nanosheet. Most Raman features eventually disappeared when a monolayer nanosheet was produced, except for the Mo-O-Mo stretching mode (Ag) at - 818 cm^-1, which was accompanied by mode-softening of up to 5 cm^-1 This mode softening, hitherto not reported for 2D α-MoO3 nanosheets, can be attributed to lattice relaxations that are validated here via theoretical density functional perturbation theory calculations. The BSA-assisted exfoliation products exhibited a blueshift in the α-MoO3 nanosheet absorption edge; they also revealed an absorption peak at 3.98 eV that can be attributed to their intrinsic exciton absorptions. These observations, together with the facile synthesis of high-purity α-MoO3 crystals, illuminate the possibility of further 2D α-MoO3 nanosheet production and lattice dynamic studies. 展开更多
关键词 α-MoO3 two-dimensionalmaterials exfoliations lattice vibrationaldynamics micro-Raman scattering
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