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Effects of Al_(2)O_(3)-sio_(2) Raw Material Types on Properties of Anorthite Based Insulation Refractories

China's Refractories 2024年第1期33卷 23-27页

作者： DU juan GUO Huishi YANG Jialin LI Wenfeng GUI Yanghai ZHAO Zhiqiang LIU Yingfan School of Materials Science and Engineering Henan University of TechnologyZhengzhou 450001China School of Materials and Chemical Engineering Zhengzhou University of Light IndustryZhengzhou 450051China

To optimize their Al_(2)O_(3)-sio_(2) raw materials,anorthite based insulation refractories were prepared by the in-situ sintering process combined with the foaming method after sintering at 1350℃for 3 h,using green and pollution-free kaolin,kyanite,andalusite and sillimanite as Al_(2)O_(3)-sio_(2) raw materials,respectively,and industrial CaCO_(3) as the CaO *** of Al_(2)O_(3)-sio_(2) raw material types on the physical properties,phase composition and microstructure were *** results are as *** samples prepared by different Al_(2)O_(3)-sio_(2) raw materials have hexagonal flake anorthite and a small amount of mullite and *** bulk density and thermal conductivity decrease in the order of using kaolin,andalusite,kyanite and sillimanite as the Al_(2)O_(3)-sio_(2) raw material,but their apparent porosity ***,in the sample with kaolin,the bonding between anorthite crystals on the pore walls is closer than that of the other samples,which is conducive to increasing the cold crushing *** bonding between anorthite crystals on pore walls gradually decreases in the order of using kyanite,andalusite and sillimanite as the Al_(2)O_(3)-sio_(2) raw material,thus their cold crushing strength decreases *** comprehensive consideration,the properties of the sample from kyanite are the *** apparent porosity,thermal conductivity and cold crushing strength are 84.6%,0.141 W·m^(-1)·K^(-1) and 1.89 MPa,respectively.

关键词： anorthite based insulation refractories Al_(2)O_(3)-sio_(2)raw materials crushing strength thermal conductivity microstructure

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无电荷层InGaAs/Si雪崩光电探测器的优化设计

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光学学报 2024年第5期44卷 19-28页

作者：张娟姚儿柯少颖闽南师范大学物理与信息工程学院光场调控及其系统集成应用福建省高校重点实验室福建漳州363000

目前,在近红外波段中普遍采用InGaAs/InP雪崩光电二极管(APD),但这类APD存在增益带宽积小和等效噪声高等问题,而InGaAs/Si APD采用电子、空穴离化系数极低的Si材料作为倍增层,在一定程度解决了上述问题,但其制造过程涉及Si电荷层的离子... 详细信息

目前,在近红外波段中普遍采用InGaAs/InP雪崩光电二极管(APD),但这类APD存在增益带宽积小和等效噪声高等问题,而InGaAs/Si APD采用电子、空穴离化系数极低的Si材料作为倍增层,在一定程度解决了上述问题,但其制造过程涉及Si电荷层的离子注入和高温退火激活,该过程工艺复杂、杂质分布不均匀、成本高。因此,本研究采用刻蚀技术在Si倍增层内制备凹槽环,并在凹槽环内填充不同介质对InGaAs层及Si层内的电场进行调控,构建无电荷层InGaAs/Si APD器件模型。结果表明,在凹槽环内填充空气或sio2可获得高性能的InGaAs/Si APD。该研究结果可为后续研制工艺简单、性能稳定、低噪声的InGaAs/Si APD提供理论指导。

关键词：探测器雪崩光电二极管增益带宽积电荷层凹槽环

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LiOH-mediated crystallization regulating strategy enhancing electrochemical performance and structural stability of sio anodes for lithium-ion batteries

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Nano Research 2024年第9期17卷 8174-8183页

作者： Zhengqiu He Zewen Xu Yu Long Jiexin Zhu Hao Yang Kuo Chen Qiang Zhou Ning Cao Xiaobo Wang juan Wang Xiaojie Tan Litao Wang Luhai Wang Shengbao He Mengdi Zhang Han Hu Mingbo Wu State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China Department of Chemistry National University of Singapore3 Science Drive 3Singapore 117543Singapore School of Chemical Sciences University of AucklandAuckland 1010New Zealand Petrochemical Research Institute Petro China Company Ltd.Beijing 102206China

Silicon monoxide(sio)is widely recognized as a promising anode material for next-generation lithium-ion *** to its metastable amorphous structure,sio exhibits a highly complex degree of crystallization at the microscopic level,which significantly influences its electrochemical *** a consequence,accurately regulating the crystallization of sio,and further establishing the relationship between crystallinity and electrochemical performance are very critical for sio *** this article,carbon-coated sio materials with different crystallinity degrees were synthesized using lithium hydroxide monohydrate(LiOH·H_(2)O)as a structural modifier to reveal this ***,moderate amount of LiOH·H_(2)O addition results in the forming of an oxygen-rich shell,which effectively inhibits the inward migration of oxygen atoms on the sio surface and suppresses volume ***,the crystallinity of sio will gradually enhance and the crystalline phase appears with increasing the amount of LiOH·H_(2)O,which will generate a deteriorative Li+diffusion *** balancing the above two contradictions,a mass fraction of 1%LiOH·H_(2)O for the additive yielded sio@C-1,characterized by optimal ***@C-1 demonstrates exceptional long-cycle stability with 74.8%capacity retention after 500 cycles at 1 A·g^(-1).Furthermore,it achieves a capacity retention of 52.2%even at a high density of 5 A·g^(-1).This study first reveals the relationship between sio crystallinity and electrochemical performance,which efficiently guides the design of high-performance sio anodes.

关键词： lithium-ion batteries sio anodes crystallinity regulation high rate long life

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退火处理对CVD生长石墨烯薄膜功函数的影响

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江苏大学学报（自然科学版） 2024年第3期45卷 362-366页

作者：姜燕程振华宋娟江苏大学材料科学与工程学院江苏镇江212013

通过退火处理去除了石墨烯薄膜上的吸附气体和杂质,改变了石墨烯表面吸附情况.利用原子力显微镜和开尔文扫描探针显微镜,对退火处理前后的石墨烯薄膜表面进行了原位扫描,分别得到其退火前、后的表面形貌和表面接触电势差图.根据表面接... 详细信息

通过退火处理去除了石墨烯薄膜上的吸附气体和杂质,改变了石墨烯表面吸附情况.利用原子力显微镜和开尔文扫描探针显微镜,对退火处理前后的石墨烯薄膜表面进行了原位扫描,分别得到其退火前、后的表面形貌和表面接触电势差图.根据表面接触电势差测量结果进一步计算其功函数,并对退火处理导致的功函数变化机理进行分析.结果表明:退火处理使得石墨烯薄膜与sio_(2)衬底间的水分子层逸出,从而导致石墨烯薄膜与sio_(2)衬底间距减小,降低了石墨烯薄膜的P型掺杂水平,使得费米能级上升、石墨烯薄膜功函数减小.

关键词：石墨烯功函数原子力显微镜退火表面接触电势差化学气相沉积法

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纳米CMOS器件中热载流子产生缺陷局域分布的表征

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物理学进展 2024年第2期44卷 96-101页

作者：马丽娟陶永春江苏联合职业技术学院南京分院南京210019 南京师范大学物理科学与技术学院南京210023

本文针对纳米小尺寸CMOS器件,提出了一种根据表面势模型表征热载流子产生电荷陷阱和界面态局域分布的方法。热载流子注入(Hot Carrier Injectione,HCI)应力会在栅氧化层和Si/sio_(2)界面中产生电荷陷阱和界面态,随着应力时间递增,这些... 详细信息

本文针对纳米小尺寸CMOS器件,提出了一种根据表面势模型表征热载流子产生电荷陷阱和界面态局域分布的方法。热载流子注入(Hot Carrier Injectione,HCI)应力会在栅氧化层和Si/sio_(2)界面中产生电荷陷阱和界面态,随着应力时间递增,这些缺陷的增多引起阈值电压等器件参数的漂移,在漏致势垒降低(Drain Induced Barrier Lowering,DIBL)效应下,可以选取表面势最大值处的阈值电压偏移量来表征沟道相应位置处HCI致电荷陷阱和界面态。研究发现,通过测量施加HCI应力前后器件阈值电压偏移量随源/漏极电压的分布,结合表面势模型计算出源/漏极电压随沟道表面势峰值的分布,可以得到HCI致电荷陷阱和界面态沿沟道的局域分布。利用此方法,精确地表征了在32 nm CMOS器件中HCI应力引起的电荷陷阱和界面态沿沟道的分布,并进一步分析了HCI效应的产生机理。

关键词： CMOS器件热载流子注入界面态电荷陷阱

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两亲性碳点在硅酸盐钻井液中的润滑性能

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钻井液与完井液 2024年第4期41卷 451-457页

作者：何丹丹赖璐梅平卢福伟吴娟长江大学化学与环境工程学院湖北荆州434023 油气田清洁生产与污染物控制湖北省工程研究中心湖北荆州434023

硅酸盐钻井液具有抑制封堵能力强、环保等优点,但其润滑性能差,这制约了硅酸盐钻井液的广泛应用。利用极压润滑仪测定含有两亲性碳点和聚氧乙烯型表面活性剂的硅酸钠溶液的润滑系数,筛选出性能优异的润滑剂,并采用总有机碳分析仪、动态... 详细信息

硅酸盐钻井液具有抑制封堵能力强、环保等优点,但其润滑性能差,这制约了硅酸盐钻井液的广泛应用。利用极压润滑仪测定含有两亲性碳点和聚氧乙烯型表面活性剂的硅酸钠溶液的润滑系数,筛选出性能优异的润滑剂,并采用总有机碳分析仪、动态光散射和接触角仪等分析其润滑机理。实验结果发现,两亲性碳点具有优良的润滑性能和耐温性,在5%硅酸钠水溶液中添加0.3%两亲性碳点C_(12)-CDs,经过110℃高温热滚16 h前后体系的极压润滑系数可从0.500左右分别降低至0.065和0.063,润滑系数降低率高达87.52%,而聚氧乙烯型表面活性剂并无润滑效果。进一步探究其润滑机理,C_(12)-CDs在石英砂表面具有优异的吸附性能,100 mg/L的C_(12)-CDs溶液吸附前后的表面张力从44.81 mN/m上升为64.03 mN/m,其吸附量可达到89.23 mg/L;且粒径分析数据表明,C_(12)-CDs可将Na_(2)sio_(3)溶液的平均粒径从514.0 nm分散为63.2 nm。碳核表面的多羟基结构和长疏水链可促进两亲性碳点在金属钻杆、井壁和硅酸聚集体表面的吸附,两亲性碳点作为润滑剂与硅酸钠钻井液体系配伍性能好,添加C_(12)-CDs的现场硅酸盐钻井液润滑系数降低率可达到86.34%,可为硅酸盐水基钻井液润滑剂的现场应用提供理论指导。

关键词：两亲性碳点硅酸盐钻井液润滑系数润滑机理

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N、B共掺杂空心碳球结构设计及其锂硫电池性能研究

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电源技术 2024年第8期48卷 1580-1587页

作者：郭德才卢雪米娟赵凡雅刘坤孙蔷中石化(大连)石油化工研究院有限公司辽宁大连116041 东北大学辽宁沈阳110819 中国电子科技集团公司第十八研究所天津300384

采用二氧化硅包覆限域碳化的方法,制备N、B共掺杂空心纳米碳球。碳球直径为245 nm,空腔内径为165 nm,比表面积为666 m^(2)/g。与非限域碳化空心碳球对比,限域碳化可以有效扩大碳球空腔直径。以空心碳球为载体制备碳硫复合正极材料,碳球... 详细信息

采用二氧化硅包覆限域碳化的方法,制备N、B共掺杂空心纳米碳球。碳球直径为245 nm,空腔内径为165 nm,比表面积为666 m^(2)/g。与非限域碳化空心碳球对比,限域碳化可以有效扩大碳球空腔直径。以空心碳球为载体制备碳硫复合正极材料,碳球的大空腔结构可以提高锂硫电池硫正极中单质硫的利用率和循环稳定性,复合材料0.1 C放电比容量809 mAh/g;1.0 C初始放电比容量716 mAh/g,循环300次后比容量551 mAh/g,每次容量损失率0.077%。同时,碳球的多孔壁层结构可以提高锂离子的传输动力学,材料表现出良好的倍率性能,5 C放电比容量为423 mAh/g。

关键词：限域碳化空心碳球碳硫正极

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Electrochemical behavior of gold and its associated minerals in alkaline thiourea solutions

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International Journal of Minerals,Metallurgy and Materials 2018年第7期25卷 737-743页

作者： he zhou yong-sheng song wen-juan li kun song national engineering laboratory of biohydrometallurgy grimat engineering institute co.ltdbeijing 101407China school of chemical&environmental engineering china university of mining&technologybeijing 100083China

Electrochemical measurements were conducted to study the electrochemical behavior of gold （Au） and its commonly associated minerals in alkaline thiourea solutions. The results indicated that without addition of any stabilizer, selective dissolution of Au from stibnite and pyrite was only possible at relatively low thiourea concentrations. As Na2sio3 was added, pyrite started to become active and an oxida- tion peak appeared; the oxidation peaks of axsenopyrite and chalcocite appeared earlier thaxl that of Au. The chalcocite peak shifted in the positive direction and the peak current increased. Stibnite did not show an oxidation peak and its current was nearly zero. Adding Na2sio3 favored the selective dissolution of Au when its minerals were associated with chalcocite and stibinte. At pH 12, the Au anode dissolution peak current increased with stabilizer concentration. At 0.38 and 0.42 V and for Na2sio3 concentration below 0.09 M, the current density continuously increased with Na2sio3 concentration. The Na2sio3 concentration had to be adequate to stabilize thiourea. When the potential was higher than 0.42 V, the surface of the Au electrode started to passivate. With an additional increase in potential, the presence of Na2sio3 could not stop the inevitable decomposition of thiourea.

关键词： alkaline daiourea Au associated mineral Na2sio3 electrochemical behavior

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Highly dispersed Ni/MgO-msio_(2)catalysts with excellent activity and stability for dry reforming of methane

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Nano Research 2022年第6期15卷 5004-5013页

作者： Fang Zeng juan Zhang Run Xu Rongjun Zhang Jianping Ge Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China Department of Coal and Syngas Conversion Research Institute of Petroleum ProcessingSINOPECBeijing 100083China

Highly dispersed Ni catalyst and alkaline promoters supported by mesoporous sio_(2)nanospheres were synthesized and applied as an active and stable catalyst for dry reforming of methane(DRM).The as-prepared Ni/MgO-msio_(2)catalyst showed stable conversions of CH4 and CO_(2)around 82%and 85%in 120 h of DRM reaction,which was superior in performance compared to similar catalysts in *** on the transmission electron microscope(TEM)images,energy-dispersive spectroscopy(EDS),CO-pulse adsorption,temperature programmed reduction of the oxidized catalysts by hydrogen(H_(2)-TPR),X-ray photoelectron spectroscopy(XPS),temperature-programmed desorption of CO_(2)(CO_(2)-TPD),and thermal gravitational analysis(TGA),the promotion effect of MgO on the Ni catalyst was systematically *** introduction of Mg^(2+)in synthesis enhanced the interaction between Ni^(2+)and msio_(2),which led to a high dispersion of active centers and a strong“metal–support”interactions to inhibit the sintering and deactivation of Ni at reaction *** the other hand,Ni and MgO nanoparticles formed adjacently on msio_(2),where the“Ni-MgO”interface not only improved the Ni0 distribution and promoted the cracking of CH_(4)but also promoted the activation of CO_(2)and the elimination of carbon deposits.A high and stable conversion of CH4 and CO_(2)were then achieved through the synergistic effect of Ni catalyst,MgO promoter,and msio_(2)support.

关键词： Ni-based catalyst dry reforming of methane mesoporous sio_(2) MgO alkaline

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Single-step thermal carburization synthesis of supported molybdenum carbides from molybdenum-containing methyl-silica

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Journal of Natural Gas Chemistry 2011年第3期20卷 271-280页

作者： juan Zou Minglin Xiang Bo How Dong Wu Yuhan Sun Hunan Changling Petrochemical S＆T Developing Co. Ltd. Yueyang 414012 Hunan China State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 Shanxi China

A novel synthesis route to obtain highly dispersed molybdenum carbides in porous silica is described. The synthesis was carried out by a single-step heat treatment of molybdenum-containing and methyl-modified silica （Mo-M-sio2） in argon atmosphere at 973 K. Mo-M-sio2 precursor was facilely obtained via a one-pot synthesis route, using （NH4）6Mo7O24 4H2O （AHM） as molybdenum sources and polymethylhydrosiloxane （PMHS） as silica sources at the initial synthetic step. The optimal C/Mo molar ratio in reaction system for complete carburization of molybdenum species was 7. The carburization process of molybdenum species followed a nontopotactic route involving a MoO2 intermediate phase, which was evidenced by XRD, N2 adsorption-desorption and in situ XPS. Formation mechanism of Mo-M-sio2 precursor was also proposed by observation of the reaction between AHM and PMHS with TEM. Furthermore, by adding TEOS into silica sources and adjusting TEOS/PMHS mass ratio, crystal phase of molybdenum carbides transferred from β-Mo2C to α-MoC1-x, and sio2 structure changed from microporous to micro/mesoporous. Catalytic performances of samples were tested using CO hydrogenation as a probe reaction. The supported molybdenum carbides exhibited high selectivity for higher alcohol synthesis compared with bulk β-Mo2C and α-MoC1-x.

关键词： molybdenum carbides porous silica single-step carburization one-pot synthesis CO hydrogenation

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