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3D Lamellar-Structured Graphene Aerogels for Thermal Interface Composites with High Through-Plane Thermal Conductivity and Fracture Toughness

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Nano-Micro Letters 2021年第2期13卷 13-27页

作者： Pengfei Liu xiaofeng Li Peng Min Xiyuan chang Chao Shu Yun Ding Zhong-Zhen Yu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although thermally conductive graphene sheets are efficient in enhancing in-plane thermal conductivities of polymers,the resulting nanocomposites usually exhibit low through-plane thermal conductivities,limiting their application as thermal interface ***,lamellarstructured polyamic acid salt/graphene oxide(PAAS/GO)hybrid aerogels are constructed by bidirectional freezing of PAAS/GO suspension followed by ***,PAAS monomers are polymerized to polyimide(PI),while GO is converted to thermally reduced graphene oxide(RGO)during thermal annealing at 300℃.Final graphitization at 2800℃ converts PI to graphitized carbon with the inductive effect of RGO,and simultaneously,RGO is thermally reduced and healed to high-quality ***,lamellar-structured graphene aerogels with superior through-plane thermal conduction capacity are fabricated for the first time,and its superior through-plane thermal conduction capacity results from its vertically aligned and closely stacked high-quality graphene *** vacuum-assisted impregnation with epoxy,the resultant epoxy composite with 2.30 vol% of graphene exhibits an outstanding through-plane thermal conductivity of as high as 20.0 W m^−1 K^−1,100 times of that of epoxy,with a record-high specific thermal conductivity enhancement of 4310%.Furthermore,the lamellar-structured graphene aerogel endows epoxy with a high fracture toughness,~1.71 times of that of epoxy.

关键词： Anisotropic aerogels Graphene Thermal conductivity Epoxy composites Fracture toughness

Surface Modification of Rice Husk Ash by Ethanol-assisted Milling to Reinforce the Properties of Natural Rubber/Butadiene Rubber Composites

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Chemical Research in Chinese Universities 2021年第3期37卷 757-762页

作者： CHEN Zhixiao QIAN Miaomiao LIU chang XUE Beichen YULiyun ZHU Yanchao WANG xiaofeng State Key Laboratory of Inorganic Synthesis&Preparative Chemistry College of ChemistryJilin UniversityChangchun130012P.R.China Jilin Province Product Quality Supervision Test Institute Changchun130103P.R.China

Rice husk ash(RHA),obtained by pyrolysis of rice husks,can be used as a potential reinforcing filler for rubber *** this work,ball milling in ethanol(ethanol-assisted milling)was used to hydroxylate the surface of RHA,promoting the graft modification of bis-(γ-triethoxysilylpropyl)-tetrasulfide(Si69).The obtained modified RHA(RHA-EM-Si69)was filled into the natural rubber/butadiene rubber(NR/BR)composites,and the filler-rubber interactions were *** consequence,RHA-EM-Si69 filled NR/BR composites showed overall improvement in the mechanical properties compared with RHA filled NR/BR *** tear strength increased from 13.37 kN/m to 34.71 kN/m,and the tensile strength increased from 1.84 MPa to 7.75 *** black(N774)was also used for comparison under the same *** method provides a potential for promoting the value of RHA in rubber industry.

关键词： Ethanol-assisted milling Rice husk ash Rubber reinforcement

The ALMA-QUARKS Survey.Ⅱ.The ACA 1.3 mm Continuum Source Catalog and the Assembly of Dense Gas in Massive Star-Forming Clumps

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Research in Astronomy and Astrophysics 2024年第6期24卷 119-139页

作者：许峰玮 Ke Wang Tie Liu Lei Zhu Guido Garay Xunchuan Liu Paul Goldsmith Qizhou Zhang Patricio Sanhueza Shengli Qin Jinhua He Mika Juvela Anandmayee Tej Hongli Liu Shanghuo Li Kaho Morii Siju Zhang Jianwen Zhou Amelia Stutz Neal JEvans Kee-Tae Kim Shengyuan Liu Diego Mardones Guangxing Li Leonardo Bronfman Ken’ichi Tatematsu chang Won Lee Xing Lu xiaofeng Mai Sihan Jiao James O.Chibueze Keyun Su Viktor L.Tóth Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Chinese Academy of Sciences South America Center for Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Departamento de Astronomía Universidad de ChileLas Condes7591245 SantiagoChile Jet Propulsion Laboratory California Institute of Technology4800 Oak Grove DrivePasadena CA 91109USA Center for Astrophysics|Harvard&Smithsonian 60 Garden StreetCambridgeMA 02138USA National Astronomical Observatory of Japan National Institutes of Natural Sciences2-21-1 OsawaMitakaTokyo 181-8588Japan Astronomical Science Program The Graduate University for Advanced StudiesSOKENDAI2-21-1 OsawaMitakaTokyo 181-8588Japan School of Physics and Astronomy Yunnan UniversityKunming 650091China Yunnan Observatories Chinese Academy of SciencesKunming 650216China Department of Physics University of HelsinkiPO Box 64FI-00014 HelsinkiFinland Indian Institute of Space Science and Technology Thiruvananthapuram 695547KeralaIndia Max Planck Institute for Astronomy Königstuhl 17D-69117 HeidelbergGermany Department of Astronomy Graduate School of ScienceThe University of Tokyo7-3-1 HongoBunkyo-kuTokyo 113-0033Japan Max-Planck-Institut für Radioastronomie Auf dem Hügel 6953121 BonnGermany Departamento de AstronomÂıa Universidad de ConcepcionCasilla 160-CConcepci onChile Department of Astronomy The University of Texas at AustinTexas 78712-1205USA Korea Astronomy and Space Science Institute 776 Daedeokdae-roYuseong-guDaejeon 34055Republic of Korea Institute of Astronomy and Astrophysics Academia SinicaRoosevelt RoadTaipei 10617TaiwanChina South-Western Institute for Astronomy Research Yunnan UniversityKunming 650091China Korea Astronomy and Space Science Institute 776 Daedeok-daeroYuseong-guDaejeon 34055Republic of

Leveraging the high resolution,sensitivity,and wide frequency coverage of the Atacama Large Millimeter/submillimeter Array(ALMA),the QUARKS survey,standing for“Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures”,is observing 139 massive starforming clumps at ALMA Band 6(λ~1.3 mm).This paper introduces the Atacama Compact Array(ACA)7 m data of the QUARKS survey,describing the ACA observations and data *** multiwavelength data,we provide the first edition of QUARKS atlas,offering insights into the multiscale and multiphase interstellar medium in high-mass star *** ACA 1.3 mm catalog includes 207 continuum sources that are called ACA *** gas kinetic temperatures are estimated using three formaldehyde transitions with a non-LTE radiation transfer model,and the mass and density are derived from a dust emission *** ACA sources are massive(16–84 percentile values of 6–160 M_(⊙)),gravity-dominated(M∝R^(1.1))fragments within massive clumps,with supersonic turbulence(M>1)and embedded star-forming *** find a linear correlation between the masses of the fragments and the massive clumps,with a ratio of 6%between the *** considering fragments as representative of dense gas,the ratio indicates a dense gas fraction(DGF)of 6%,although with a wide scatter ranging from 1%to 10%.If we consider the QUARKS massive clumps to be what is observed at various scales,then the size-independent DGF indicates a self-similar fragmentation or collapsing mode in protocluster *** the ACA data over four orders of magnitude of luminosity-to-mass ratio(L/M),we find that the DGF increases significantly with L/M,which indicates clump evolutionary *** observed a limited fragmentation at the subclump scale,which can be explained by a dynamic global collapse process.

关键词： stars:formation ISM:kinematics and dynamics ISM:clouds stars:protostars

稻草微贮早期真菌群落演变及其木质纤维素降解酶的预测

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微生物学通报 2024年第5期51卷 1614-1625页

作者：常帅飞任文义程雨辰李娅楠何金童张力莉徐晓锋宁夏大学动物科技学院宁夏银川750021

【背景】木质纤维素的难降解性是导致稻草资源产量丰富却难以广泛用于牲畜饲料的根本原因。【目的】研究稻草微贮早期发酵过程中真菌群落演变过程及真菌对木质纤维素的降解作用。【方法】以1.2×106CFU/g-DM的地衣芽孢杆菌复合5×106CFU... 详细信息

【背景】木质纤维素的难降解性是导致稻草资源产量丰富却难以广泛用于牲畜饲料的根本原因。【目的】研究稻草微贮早期发酵过程中真菌群落演变过程及真菌对木质纤维素的降解作用。【方法】以1.2×106CFU/g-DM的地衣芽孢杆菌复合5×106CFU/g-DM的植物乳杆菌添加进行稻草微贮。于不同时间节点(1、3、7和15d)进行internaltranscribedspacer(ITS)真菌群落分析。【结果】稻草微贮的第7天真菌群落多样性最高。发酵过程中的优势菌门依次为子囊菌门(Ascomycetes)(64.2%)和担子菌门(Basidiomycota)(30.2%)。与第1天相比,子囊菌门相对丰度分别在第7天和第15天均极显著升高(P<0.001);担子菌门相对丰度在第7天和第15天均极显著降低(P<0.001)。优势菌属依次为汉纳菌属(Hannaella)(11.6%)、伊萨菌属(Issatchenkia)(8.1%)、哈萨克斯坦菌属(Kazachstania)(6.3%)、酿酒酵母属(Saccharomyces)(6.2%)、线黑粉酵母菌属(Filobasidium)(5.1%)。枝顶孢属(Acremonium)(2.4%)和曲霉属(Aspergillus)(2.2%)是发酵过程中的次优菌属。与第1天相比,汉纳菌属相对丰度在第15天极显著降低(P<0.001);枝顶孢属和曲霉属相对丰度均在第7天极显著升高(P<0.001)。PICRUSt预测结果表明:β-葡萄糖苷酶、漆酶、α-半乳糖苷酶和β-甘露糖苷酶是丰度最高的木质纤维素降解酶。Spearman相关性分析结果表明,担子菌门与β-甘露糖苷酶有显著正相关关系(P<0.05)。汉纳菌属与β-葡萄糖苷酶和β-甘露糖苷酶有显著正相关关系(P<0.05)。枝顶孢属和曲霉属均与β-葡萄糖苷酶、β-甘露糖苷酶、漆酶和α-半乳糖苷酶有极显著正相关关系(P<0.001)。【结论】在稻草微贮过程中,真菌对木质纤维素有降解作用。本文为真菌在微贮过程中的有效利用以及木质纤维素的生物降解提供了理论依据。

关键词：稻草微贮真菌枝顶孢属 β-葡萄糖苷酶

形态学曲面断层下颌指数PMI分析口腔种植区下颌骨骨密度

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山西医科大学学报 2015年第9期46卷 924-928页

作者：柴娟常晓峰徐平杜良智贺龙龙朱飞黄硕西安医学院口腔系口腔颌面外科教研室西安710021 西安交通大学口腔医院种植中心西安西电集团医院

目的探讨应用形态学曲面断层下颌指数(panoramic radiomorphometric indexes,PMI),结合锥形束CT(cone beam computed tomography,CBCT)相对灰度值及临床种植扭力(implant insertion torque,IT)的方法分析口腔种植区下颌骨骨密度。方法 60例下颌骨后牙区缺失牙齿的患者接受CBCT摄影。测量下颌骨种植区CBCT相对骨密度灰度值,曲面断层下颌指数PMI,并在临床种植手术中记录骨质和种植扭力。采用秩和检验和Pearson线性检验统计学方法分析,SPSS19.0软件数据处理。结果 1Ⅰ类骨质,Ⅱ/Ⅲ类骨质,Ⅳ类骨质CBCT相对骨密度灰度值分别为(730.12±135.83)HU,(600.27±342.58)HU,(212.54±32.61)HU;IT为(50±5)N/cm,(40±5)N/cm,(30±5)N/cm;PMI分别为0.44±0.82,0.36±0.76,0.23±0.52。2Ⅰ-Ⅳ类骨质分类PMI不同,差异有统计学意义(F>1,P0.05);年龄段分组比较中差异有统计学意义(F>1,P<0.05),且30-39岁的CBCT骨密度灰度值和PMI值最大。结论形态学曲面断层下颌指数PMI值在临床口腔种植简易判断下颌骨骨密度及术中判断种植扭力具有指导意义。

关键词：锥形束CT 骨密度种植扭力 PMI

安罗替尼联合化疗在儿童复发难治软组织肉瘤中的初步观察

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中华转移性肿瘤杂志 2021年第4期04卷 283-286页

作者：朱志云王焕民常晓峰孟德光王佳荣国家儿童医学中心首都医科大学附属北京儿童医院肿瘤外科，北京100045 北京儿童医院保定医院保定市儿童医院肿瘤外科，保定071000

目的探讨安罗替尼联合化疗在治疗儿童复发难治软组织肉瘤中的近期疗效和安全性。方法收集2020—2021年北京儿童医院保定医院应用安罗替尼联合化疗治疗的6例儿童复发难治的软组织肉瘤的病例资料,回顾分析其病例特点、近期效果及不良反应... 详细信息

目的探讨安罗替尼联合化疗在治疗儿童复发难治软组织肉瘤中的近期疗效和安全性。方法收集2020—2021年北京儿童医院保定医院应用安罗替尼联合化疗治疗的6例儿童复发难治的软组织肉瘤的病例资料,回顾分析其病例特点、近期效果及不良反应。结果6例患儿中男3例、女3例。本方案治疗开始时中位年龄41个月(7~192个月)。1例肿瘤复发再次术后引入安罗替尼预防复发的患儿,目前已达到术后7个月无瘤生存。其余5例为争取手术机会术前开始应用安罗替尼联合化疗,部分缓解3例,疾病稳定2例;除1例复发患儿因化疗合并症死亡未再手术,其余4例手术时均可完整切除。随访6例患儿,4例无瘤生存,其中3例顺利结疗,1例术后继续安罗替尼联合化疗中;2例患儿死亡,1例因肿瘤进展死亡,1例因化疗合并症死亡。4例患儿出现脂质代谢异常。结论安罗替尼联合化疗治疗复发难治的儿童软组织肉瘤的近期疗效较好,不良反应可耐受,今后需进一步扩大样本例数验证。

关键词：安罗替尼软组织肉瘤/化学疗法儿童

Expression of the mouse metallothionein mutant ββ-cDNA in the lettuces (Lactuca sativa L.)

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Chinese Science Bulletin 2002年第7期47卷 558-562页

作者： Zuo xiaofeng Zhang Yukun Wu Beibei chang Xing Ru Binggen State Key Laboratory of Protein Engineering and Plant Genetic Engineering Peking University100871BeijingChina

Mouse metallothionein (MT) domain mutant ββ-cDNA gene has been inserted into the plant expression vector pGPTVd35S which has herbicide (PPT)-resistance gene bar as a selective marker. The chimeric gene was introduced into the lettuce (Lactuca sativa L. cv Salinas 88) by Agrobacterium-mediated transformation. PCR and Southern blot analysis of some putative transformants indicated that the introduced ββ-cDNA was integrated into lettuce genome and inheritted by sexual reproduction. The expression of ββ gene in lettuce plants was demonstrated by Northern and Western blot analysis. Meanwhile, the zinc content of the transformed lettuce plants is up to 400 μg/g dry weight, remarkably higher than the control plants.

关键词： metallothionein domain mutant pp gene zinc content lettuce.

Vertically aligned reduced graphene oxide/Ti_(3)C_(2)T_(x)MXene hybrid hydrogel for highly efficient solar steam generation

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Nano Research 2020年第11期13卷 3048-3056页

作者： Wei Li xiaofeng Li Wei chang Jing Wu Pengfei Liu Jianjun Wang Xi Yao Zhong-Zhen Yu State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing100029China Institute of Chemistry Chinese Academy of SciencesBeijing100190China Department of Biomedical Sciences City University of Hong KongHong Kong999077China Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing100029China

Effective utilization of abundant solar energy for desalination of seawater and purification of wastewater is one of sustainable techniques for production of clean water,helping relieve global water resource ***,we fabricate a vertically aligned reduced graphene oxide/Ti_(3)C_(2)T_(x)MXene(A-RGO/MX)hybrid hydrogel with aligned channels as an independent solar steam generation device for highly efficient solar steam *** vertically aligned channels,generated by a liquid nitrogen-assisted directional-freezing process,not only rapidly transport water upward to the evaporation surface for efficient solar steam generation,but also facilitate multiple reflections of solar light inside the channels for efficient solar light *** deliberate slight reduction endows the RGO with plenty of polar groups,decreasing the water vaporization enthalpy effectively and hence accelerating water evaporation *** MXene sheets,infiltrated inside the A-RGO hydrogel on the basis of Marangoni effect,enhance light absorption capacity and photothermal conversion *** a result,the A-RGO/MX hybrid hydrogel achieves a water evaporation rate of 2.09 kg·m^(−2)·h^(−1)with a high conversion efficiency of 93.5%under 1-sun ***,this photothermal conversion hydrogel rapidly desalinates seawater and purifies wastewater to generate clean water with outstanding ion rejection rates of above 99%for most ions.

关键词： anisotropic hydrogel MXene reduced graphene oxide solar steam generation aligned channels

Mg-Zn-Y-Nd coated with citric acid and dopamine by layer-by-layer self-assembly to improve surface biocompatibility

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Science China(Technological Sciences) 2018年第8期61卷 1228-1237页

作者： CHEN Li LI JingAn chang JiaWei JIN ShiBo WU Di YAN HaoHao WANG xiaofeng GUAN ShaoKang School of Materials Science and Engineering Zhengzhou UniversityZhengzhou450001China School of Life Science Zhengzhou UniversityZhengzhou 450001 China National Center for International Research of Micro-nano Molding Technology & Key Laboratory for Micro Molding Technology of Henan Province Zhengzhou 450001 China

Magnesium alloy has been generally accepted as an important biodegradable material on cardiovascular stent development for a long time. However, its limited biocompatibility, especially delayed endothelialization process restricts its further application. In this contribution, we modified the Mg-Zn-Y-Nd alloy surface with citric acid and dopamine via a layer-by-layer self-assembly assay, aiming at improving the biocompatibility of the magnesium alloy. The citric acid/dopamine(CA/PDA) layer exhibited a remarkable suppression of platelet activation/aggregation and thrombosis under 15 dyn/cm2 blood flowing. Inhibition on vascular smooth muscle cells growth and macrophages attachment/activation were also observed on this layer. In particular, the CA/PDA layer presented a promoted property for the vascular endothelial cells growth and spreading compared with the bare magnesium alloy, suggesting the pro-endotelialized function. In conclusion, this research may support potential application on surface modification of magnesium alloy based cardiovascular stents for better biocompatibility.

关键词： cardiovascular stent Mg-Zn-Y-Nd alloy biocompatibility layer-by-layer self-assembly citric acid dopamine