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Dwell scheduling for MFIS with aperture partition and JRC waveform
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作者 CHENG Ting LIU Luqing HENG Siyu 《Journal of Systems Engineering and Electronics》 2025年第4期951-961,共11页
The multifunctional integration system(MFIS)is based on a common hardware platform that controls and regulates the system’s configurable parameters through software to meet dif-ferent operational requirements.Dwell s... The multifunctional integration system(MFIS)is based on a common hardware platform that controls and regulates the system’s configurable parameters through software to meet dif-ferent operational requirements.Dwell scheduling is a key for the system to realize multifunction and maximize the resource uti-lization.In this paper,an adaptive dwell scheduling optimization model for MFIS which considers the aperture partition and joint radar communication(JRC)waveform is established.To solve the formulated optimization problem,JRC scheduling condi-tions are proposed,including time overlapping condition,beam direction condition and aperture condition.Meanwhile,an effec-tive mechanism to dynamically occupy and release the aperture resource is introduced,where the time-pointer will slide to the earliest ending time of all currently scheduled tasks so that the occupied aperture resource can be released timely.Based on them,an adaptive dwell scheduling algorithm for MFIS with aperture partition and JRC waveform is put forward.Simulation results demonstrate that the proposed algorithm has better com-prehensive scheduling performance than up-to-date algorithms in all considered metrics. 展开更多
关键词 multifunctional integration system(mfis) dwell scheduling aperture partition joint radar communication(JRC).
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MFIS结构的C-V特性 被引量:3
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作者 颜雷 汤庭鳌 +3 位作者 黄维宁 姜国宝 钟琪 汤祥云 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2000年第12期1203-1207,共5页
研究了运用 SOL- GEL方法制备的 Au/PZT(铅锆钛 ) /Zr O2 /Si结构电容即 MFIS(Met-al/Ferroelectric /Insulator/Semiconductor)电容的方法 ,并对其进行了 SEM、C- V特性测试及Zr O2 介质层介电常数分析 .研究了 C- V存储窗口 (Memory W... 研究了运用 SOL- GEL方法制备的 Au/PZT(铅锆钛 ) /Zr O2 /Si结构电容即 MFIS(Met-al/Ferroelectric /Insulator/Semiconductor)电容的方法 ,并对其进行了 SEM、C- V特性测试及Zr O2 介质层介电常数分析 .研究了 C- V存储窗口 (Memory Window)电压与铁电薄膜和介质层厚度比的关系 ,得出 MFIS电容结构中最佳铁电薄膜和介质层厚度比为 7— 1 0左右 ,在外加电压- 5V- +5V时存储窗口可达 2 .52 V左右 . 展开更多
关键词 mfis C-V特性 存储窗口 铁电薄膜 电滞回线
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应用于非破坏性读出铁电存储器的MFIS FET制备及其特性 被引量:2
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作者 颜雷 林殷茵 +2 位作者 汤庭鳌 黄维宁 姜国宝 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第3期301-304,共4页
将 Zr O2 和 PZT的 sol- gel薄膜制备技术应用到非破坏性读出铁电存储器中 ,制作出应用 Al/ PZT/ Zr O2 / p- Si结构的 MFIS电容和单管 MFIS FET,研究了 MFIS电容的界面和存储窗口特性 ,结果表明 Zr O2 介质阻挡层和 Si衬底以及 PZT的... 将 Zr O2 和 PZT的 sol- gel薄膜制备技术应用到非破坏性读出铁电存储器中 ,制作出应用 Al/ PZT/ Zr O2 / p- Si结构的 MFIS电容和单管 MFIS FET,研究了 MFIS电容的界面和存储窗口特性 ,结果表明 Zr O2 介质阻挡层和 Si衬底以及 PZT的附着良好 ,在± 5 V测试电压、1MHz测试频率下 ,存储窗口电压为 2 .6 V左右 ,与相应的铁电薄膜的正、负矫顽电压差值的比为 0 .8.对于宽长比为 5 0 0μm / 5 0μm器件 ,采用栅极与源极、漏极写入方式 ,± 10 V时在写入电压下得到理想的输入 -输出特性 ;小尺寸的 4 0μm/ 8μm器件在± 5 展开更多
关键词 铁电存储器 非破坏性读出 铁电薄膜 mfis FET
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用于非破坏性读出铁电存储器的MFIS结构的机理研究
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作者 林殷茵 汤庭鳌 《固体电子学研究与进展》 CAS CSCD 北大核心 2003年第3期323-328,共6页
分析了 MFIS FET的工作机理以及影响 MFIS电容的存储窗口特性的因素 ,提出用存储窗口与铁电薄膜正、负矫顽电压的差值来评价存储窗口特性 ,制备了 Au/Cr/PZT/Zr O2 /Si的 MFIS结构并研究了其存储窗口特性 ,存储窗口随 Zr O2 的厚度变化... 分析了 MFIS FET的工作机理以及影响 MFIS电容的存储窗口特性的因素 ,提出用存储窗口与铁电薄膜正、负矫顽电压的差值来评价存储窗口特性 ,制备了 Au/Cr/PZT/Zr O2 /Si的 MFIS结构并研究了其存储窗口特性 ,存储窗口随 Zr O2 的厚度变化呈现一个极大值 ,甚至会出现 C-V曲线方向的变化 ,而 PZT薄膜的厚度增大会导致窗口增大 ,这是由于界面效应以及在铁电层和介质阻挡层上电压分配关系的不同而造成的 ,这一结果与前面的分析很好地吻合。当 Zr O2 和 PZT的厚度分别为 3 0 nm和 2 5 0 nm、扫描电压从 -5 V到 +5 V变化时 ,存储窗口大小为 2 .5 V,与相应的铁电薄膜的正、负矫顽电压的差值的比为 0 .8。 展开更多
关键词 铁电存储器 mfis结构 金属-铁电-绝缘层-半导体 场效应晶体管 非破坏性读出 工作机理
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基于Preisach的MFIS结构器件C-V模型的改进
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作者 张俊杰 王希娟 《科学技术与工程》 2011年第17期4060-4063,共4页
考虑历史电场效应,将描述铁电层矫顽电场分布的Preisach模型引入MFIS结构,和传统的MOS结构器件电荷薄片模型结合,对MFIS结构的C-V模型进行改进。为验证模型的有效性,与文献中的实验数据进行比较。结果表明,改进模型能够很好地与实验数... 考虑历史电场效应,将描述铁电层矫顽电场分布的Preisach模型引入MFIS结构,和传统的MOS结构器件电荷薄片模型结合,对MFIS结构的C-V模型进行改进。为验证模型的有效性,与文献中的实验数据进行比较。结果表明,改进模型能够很好地与实验数据吻合,可以被用来描述MFIS结构器件的C-V特性及记忆窗口。 展开更多
关键词 铁电 金属铁电绝缘半导体(Metal-Ferroelectrie-insulator-Semiconluctor) mfis C-V 记忆窗口
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基于Atlas的MFIS结构器件电学性能模拟
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作者 张俊杰 《电子科技》 2011年第6期23-25,共3页
利用Atlas器件模拟软件,对MFIS结构器件的C-V特性及记忆窗口进行模拟。讨论了应用电压、绝缘层厚度及绝缘层材料等因素,对MFIS结构器件记忆能力及稳定性的影响,为MFIS结构器件的设计和性能提高提供了参考。
关键词 mfis 记忆窗口 C-V特性 ATLAS
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The Default Risk Management in Financial Institutions: Case of the Credit Risk in Lebanese MFIs
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作者 Riad Makdessi Selim Mekdessi 《Economics World》 2014年第2期112-123,共12页
In Lebanon, as in some countries, the major financial institutions in the economy experienced by the country in the aftermath of independence were banks and insurance companies. However, the operation of these financi... In Lebanon, as in some countries, the major financial institutions in the economy experienced by the country in the aftermath of independence were banks and insurance companies. However, the operation of these financial institutions obeys to some requirements that are not often likely to allow economic agents with low purchasing power to obtain the necessary funds to finance their production activities. Microfinance therefore comes in as the beginning of seeking effective market oriented solutions to the provision of substantial and effective financial resource for poor groups of people who do not have access to financial service from formal government and private financial institution. Microfinance Institutions (MFIs) are created for a social and sometimes non-profit objective. In Lebanon, many limitations hinder the development of MFIs including the lack of regulations, economic conditions, insecurity, political conflict, financial resources, and the risk of interest rates. Microfinance in Lebanon saw the light during the 1975-1990 Civil War through programs of charitable and community organizations, and really started to develop only in the second half of the 1990s. Capping interest rates may affect the access of poor people to financial services. The problem is that the granting of very small loans involves inevitably higher administrative costs than those offered by traditional bank loans. Therefore, MFIs that seek profitability should have higher interest rates than those charged by traditional banks. By providing money to poor people, how do MFIs in Lebanon reduce the credit risk? This theme's treatment requires a qualitative analysis development. Indeed, after the selection of a representative sample, semi-structured interviews were done with the MFIs managers, and several researches done on this topic were analyzed. The data obtained from the above are treated by the triangulation of different data and the interviews analysis by the method of discourse content analysis. In addition, a literature review was done through scientific journals, books, newspapers, and websites. 展开更多
关键词 default risk MICROFINANCE mfis credit risk Lebanese mfis
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新型铁电薄膜在MFIS器件中的应用
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作者 王树雨 芦春光 +4 位作者 袁秋婷 仇加俊 付跃举 蔡淑珍 傅广生 《河北大学学报(自然科学版)》 CAS 北大核心 2023年第4期364-368,共5页
利用新型铁电材料Na 0.5 Y 0.5 TiO 3(NYTO)薄膜高介电的特点,将其作为MFIS(metal-ferroelectric-insulator-semiconductor,MFIS)电容器的绝缘层,制备出Pt/Pb(Zr 0.2 Ti 0.8)O 3/NYTO/Si结构电容器,并对其进行XRD、SEM、C-V特性测试及I-... 利用新型铁电材料Na 0.5 Y 0.5 TiO 3(NYTO)薄膜高介电的特点,将其作为MFIS(metal-ferroelectric-insulator-semiconductor,MFIS)电容器的绝缘层,制备出Pt/Pb(Zr 0.2 Ti 0.8)O 3/NYTO/Si结构电容器,并对其进行XRD、SEM、C-V特性测试及I-V特性测试分析.分别对C-V存储窗口(记忆窗口,memory window)与应用电压以及绝缘层膜厚的关系进行了研究,结果表明记忆窗口数值比较理想.绝缘层厚度为40 nm、电容器的应用电压为32 V时,记忆窗口可达13 V.对制备的MFIS电容器I-V特性进行了研究,结果表明器件具备较低的漏电流密度,为1.08×10-6 A/cm 2,且其电流传导机制符合空间电荷限制电流导电机制. 展开更多
关键词 新型铁电薄膜 mfis电容器 记忆窗口 C-V特性
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Simulation of electric properties of MFIS capacitor with BNT ferroelectric thin film using Silvaco/Atlas 被引量:1
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作者 郑学军 张俊杰 +3 位作者 周益春 唐明华 杨博 陈义强 《中国有色金属学会会刊:英文版》 CSCD 2007年第A02期752-755,共4页
Metal-ferroelectric-insulator-silicon(MFIS) capacitors with Bi3.15Nd0.85Ti3O12(BNT) ferroelectric thin film were simulated using a commercial software Silvaco/Atlas,and the effects of applied voltage and insulator lay... Metal-ferroelectric-insulator-silicon(MFIS) capacitors with Bi3.15Nd0.85Ti3O12(BNT) ferroelectric thin film were simulated using a commercial software Silvaco/Atlas,and the effects of applied voltage and insulator layer on capacitance-voltage(C-V) hysteresis loops and memory windows were investigated. For the MFIS capacitors with CeO2 insulator,with the increase of applied voltage from 2 V to 15 V,the C-V loops become wider and memory windows increase from 0.15 V to 1.27 V. When the thickness of CeO2 layer increases from 1 nm to 5 nm at the applied voltage of 5 V,the C-V loops become narrower and the memory windows decrease from 1.09 V to 0.36 V. For MFIS capacitors with different insulator layers(CeO2,HfO2,Y2O3,Si3N4 and SiO2),the high dielectric constants can make the C-V loops wider and improve the capacitor's memory window. The simulation results prove that Silvaco/Atlas is a powerful simulator for MFIS capacitor,and they are helpful to the fabrication of MFIS nonvolatile memory devices. 展开更多
关键词 mfis电容器 铁电薄膜 介电性能 模拟
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The Impact of Corporate Governance and Ethics on Microfinance Institutions (MFIs)—The Case for Microfinance Institutions (MFIs) in Masvingo, Zimbabwe, 2009-2019
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作者 Ephraim Matanda Vharawei Matanda 《Journal of Modern Accounting and Auditing》 2019年第11期510-522,共13页
The paper presents and examines the impact of corporate governance and ethics in particular on sustainable development of the Zimbabwean microfinance sector in the period 2009-2019.The critical microfinance institutio... The paper presents and examines the impact of corporate governance and ethics in particular on sustainable development of the Zimbabwean microfinance sector in the period 2009-2019.The critical microfinance institutions(MFIs)crisis experienced in Masvingo,Zimbabwe recently was not the first one in the world in terms of its severity.The main aim of MFIs in any economy is to serve the poor and vulnerable people of a society through providing them with soft or concessional loans,insurance coverage,and facilities for savings.The study used the descriptive qualitative design to draw research data from MFIs dotted in and around Masvingo Province for presentation,analysis,and interpretation.One of the major findings of the study was that corporate governance and ethics played an indispensable role in the growth and development of MFIs’products and services.The study also realized that good corporate governance and ethical behaviours in business practices were essential for the success of any organization and vice versa and MFIs were no exception.The study therefore concluded that poor capital formation,corporate governance and ethics,human recruitment and selection procedures and fraudulent activities or misappropriation of funds were responsible for the majority of threats faced by MFIs in Masvingo in their growth and development endeavours.Therefore the study recommended that directors of MFIs should craft policies and strategies that are corporate governance and ethics oriented in their desire to grow their business towards sustainable development in the foreseeable future. 展开更多
关键词 CORPORATE governance CORPORATE ETHICS MICROFINANCE sector concessional LOANS MICROFINANCE institutions (mfis) sustainable development
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An Inside View of Microcredit in Panama: The Financial Investment in MFIs
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作者 Anna Paola Micheli 《Economics World》 2015年第3期128-136,共9页
The idea of this survey on microfinance in Panama arises from the importance of this financial sector in Latin America, in particular this paper analyzes the system of microcredit and estimate, among other things, the... The idea of this survey on microfinance in Panama arises from the importance of this financial sector in Latin America, in particular this paper analyzes the system of microcredit and estimate, among other things, the financial needs of the institutions of microcredit as a potential target of international investment. The present paper aims to provide a cognitive framework on microcredit in Panama. It wants to demonstrate how this country can be an area in which international investors can operate considering that this form of credit can improve their yields especially in countries, such as Panama, characterized by high interest rates. Under the methodological point of view, the paper considers the financial variables of microcredit in Panama. In this way, it reaches the goal of the research to identify MFIs (micro finance institutions) as a potential target of investors. 展开更多
关键词 mfis (micro finance institutions) MICROCREDIT investor strategy MICROFINANCE financial sector development interest rate
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Economic Empowerment of Rural Women:Case Study of Microfinance Institution(MFIs)in Tangerang,Indonesia
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作者 Mukhaer Pakkanna Lincolin Arsyad Agustinus Suryantoro 《Sociology Study》 2015年第11期865-874,共10页
The aim of this research is to extract information from married female clients who utilize financing,empowering,and other facilities provided by Microfinance Institutions(MFIs).Quantitative descriptive approach is use... The aim of this research is to extract information from married female clients who utilize financing,empowering,and other facilities provided by Microfinance Institutions(MFIs).Quantitative descriptive approach is used in order to describe MFIs.Specifically,the difference between MFIs in each area will be overviewed by using statistical instruments of testing for a difference between means and independent F-test.On the other hand,descriptive qualitative approach is used to review the social interactions of female clients.The results of this research have uncovered some facts.First,however,Difference-Between-Two-Means Test has revealed that no significant difference is found.This shows that the empowering aspect that has been done by MFIs conforms with the standard.Second,the fact that no significant difference is found in the empowering process has been backed by data that reveals relatively small loans scale,similarity in business models,unvaried necessity,relatively small expenditure and living cost,low access to education,and good accessibility to MFIs.Third,business models that are desirable by female clients have these characteristics:only requiring a minimum amount of capital;durable;fast-moving;focusing more on costumers;adaptable;contributing to the socieW's economy;flexible;having a set amount of freedom. 展开更多
关键词 Women empowering Microfinance Institutions(mfis) fishermen society agricultural society industrial area
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催化裂化技术在炼油企业转型发展中的地位与作用
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作者 施俊林 王伟 《石油炼制与化工》 北大核心 2025年第5期180-186,共7页
“十四五”中后期,我国的能源结构调整处于关键的十字路口。面临“新能源乘用车发展迅猛”“成品油消费峰值来临”以及“化工市场长达十个季度以上的亏损周期”等复杂格局,传统炼油企业既要发展实体经济,也要端好、端稳能源饭碗。坚定... “十四五”中后期,我国的能源结构调整处于关键的十字路口。面临“新能源乘用车发展迅猛”“成品油消费峰值来临”以及“化工市场长达十个季度以上的亏损周期”等复杂格局,传统炼油企业既要发展实体经济,也要端好、端稳能源饭碗。坚定油化转型主基调,以新型催化剂及新型反应器构型为抓手,整合炼油厂资源,力求低成本、高竞争力地使减量的汽油产品转化为低碳烯烃。中国石化天津分公司牵头的开发团队优化整合出新型催化裂化(裂解)FCO技术,以第一提升管新鲜进料为基准,可产出6.5%~10.6%(w)乙烯、22%(w)丙烯,能耗为63~72 kgOE t(1 kgOE=41.8 MJ),为存量资产保值、增值开辟新的转型道路,在转型过渡期,深挖催化裂化技术潜力,筑牢了催化裂化技术在总流程中的关键地位。 展开更多
关键词 催化裂化 炼油转型 MFI分子筛 靶向催化裂化 FCO技术
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HfO_(2)铁电薄膜基MFIS存储结构中的高κ介电晶籽层效应研究:铁电正交相生长和界面电荷注入抑制 被引量:2
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作者 张岩 王岛 +10 位作者 王佳丽 罗春来 李明 李育珊 陶瑞强 陈德扬 樊贞 戴吉岩 周国富 陆旭兵 刘俊明 《Science China Materials》 SCIE EI CAS CSCD 2023年第1期219-232,共14页
HfO_(2)基材料铁电场效应晶体管(FeFET)商业化应用面临的一个重要挑战是其疲劳特性差.本文提出,在基于金属-铁电-绝缘层-半导体(MFIS)栅叠层结构的FeFET中研发合适的高κ界面晶籽层(SL)以大幅度提升其疲劳性能.我们在ZrO_(2),HfO_(2),(H... HfO_(2)基材料铁电场效应晶体管(FeFET)商业化应用面临的一个重要挑战是其疲劳特性差.本文提出,在基于金属-铁电-绝缘层-半导体(MFIS)栅叠层结构的FeFET中研发合适的高κ界面晶籽层(SL)以大幅度提升其疲劳性能.我们在ZrO_(2),HfO_(2),(HfO_(2))0.75(Al_(2)O_(3))0.25(HAO)和Al_(2)O_(3)等典型的高κ介电SL上制备了Hf_(0.5)Zr_(0.5)O_(2)(HZO)铁电薄膜,系统研究了HZO薄膜的微观结构、铁电性及其MFIS器件的存储特性.首先,揭示了HZO薄膜中铁电正交相的形核和生长不仅受高κ介电SL表面能的影响,而且其微观结构对HZO中正交相的形成也起到重要作用.其次,澄清了高κ介电晶籽层对MFIS结构存储特性的影响,通过精确计算的MFIS结构的界面层电场,对MFIS结构的存储特性做出了合理解释.最后,基于HAO的高κSL的MFIS器件实现了铁电极化和界面电荷注入之间的合理优化,并且获得了较大铁电存储窗口(>1.0 V),出色的保持特性(>1.6×104s)和疲劳特性(>105).本文为未来解决HfO_(2)基Fe FET的疲劳问题提供了有价值的思路,为在介电SL上生长HfO_(2)铁电薄膜的其他高性能电子器件的开发提供了参考. 展开更多
关键词 存储特性 存储结构 铁电薄膜 商业化应用 mfis 铁电存储 疲劳特性 叠层结构
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Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol 被引量:2
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作者 Peng Zhu Cun Liu +5 位作者 Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong Liu Guohui Yang 《Journal of Energy Chemistry》 2025年第1期458-468,共11页
Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive st... Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented growth.The obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis. 展开更多
关键词 MFI zeolite ZSM-5 NANOSHEETS Scale-up synthesis Aromatic alkylation
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流式细胞术检测HLA-C分子表达水平的影响因素探讨
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作者 李宇楠 江任辉 +2 位作者 蔡思齐 刘洁 邓志辉 《中国输血杂志》 2025年第1期79-84,共6页
目的探讨流式细胞术检测HLA-C分子表达水平的影响因素。方法收集2024年3—5月外周造血干细胞志愿捐献者CD34细胞计数检测后剩余的单采造血干细胞悬液标本共12例,分别探讨读取有核细胞不同数量(50万、5万、0.5万个)、加入红细胞裂解液及... 目的探讨流式细胞术检测HLA-C分子表达水平的影响因素。方法收集2024年3—5月外周造血干细胞志愿捐献者CD34细胞计数检测后剩余的单采造血干细胞悬液标本共12例,分别探讨读取有核细胞不同数量(50万、5万、0.5万个)、加入红细胞裂解液及抗体的先后顺序不同、距离失效期时长不同的HLA-C抗体,对HLA-C表达水平检测结果的影响,并采用Student t检验分析组间差异显著性。结果分别读取50万、5万、0.5万个有核细胞,3组数据组间HLA-C阳性细胞占比、平均荧光强度差异均无显著性(P>0.05);加入红细胞裂解液及抗体的先后顺序不同,对于HLA-C阳性细胞占比差异无显著性(P>0.05);但“先裂解红细胞再加抗体”的HLA-C MFI值显著低于“先加抗体再裂解红细胞”的MFI值(P<0.05);使用距失效期仍有24个月的HLA-C抗体所检出的阳性细胞占比及MFI值,显著高于距失效期仅剩有5个月的HLA-C抗体(P<0.05)。结论本文探讨了流式细胞术检测HLA-C分子表达水平的影响因素,研究结果对规范HLA-C表达水平的实验操作、提高检测结果的准确性和可比性具有良好的参考和应用价值。 展开更多
关键词 人类白细胞抗原(HLA) HLA-C基因 表达水平 流式细胞术 平均荧光强度(MFI)
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FER/MFI混晶分子筛的合成及其催化1-己烯裂解性能
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作者 马艺轩 刘建强 +3 位作者 欧阳颖 邢恩会 罗一斌 舒兴田 《石油学报(石油加工)》 北大核心 2025年第4期901-909,共9页
以吡咯烷为模板剂,通过引入不同添加量的十六烷基三甲基溴化铵(CTAB),成功合成了一系列FER分子筛及FER/MFI混晶分子筛,采用XRD、BET、XRF、SEM和NH3-TPD等手段对其进行分析表征,并系统探究其催化1-己烯裂解反应性能。结果表明:CTAB的引... 以吡咯烷为模板剂,通过引入不同添加量的十六烷基三甲基溴化铵(CTAB),成功合成了一系列FER分子筛及FER/MFI混晶分子筛,采用XRD、BET、XRF、SEM和NH3-TPD等手段对其进行分析表征,并系统探究其催化1-己烯裂解反应性能。结果表明:CTAB的引入显著影响分子筛的孔结构和酸性,高CTAB含量(CTAB/SiO_(2)摩尔比0.10)条件下,形成FER与MFI双晶相共存结构的混晶分子筛,其微孔与外比表面积的协同作用优化了酸位点分布;在反应温度为550℃、压力为0.1 MPa、催化剂/1-己烯质量比为1、LHSV为51.4 h^(-1)条件下,经磷改性及水热老化处理后的混晶FER/MFI分子筛PC-0.10-H样品催化1-己烯裂解时表现出最优性能,1-己烯转化率达74.00%,三烯(乙烯、丙烯和丁烯)总收率达53.24%。1-己烯在MFI相中优先发生叠合生成C_(12)^(+)中间体,随后在FER相中进一步裂解为低碳烯烃,双相协同机制既提升了裂解效率,又抑制了副反应。FER/MFI混晶分子筛的合成及其双相协同机制为开发高效催化裂解催化剂提供了新思路。 展开更多
关键词 十六烷基三甲基溴化铵(CTAB) FER/MFI混晶分子筛 1-己烯 催化裂解 协同机制
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Co nanoparticles confined in mesopores of MFI zeolite for selective syngas conversion to heavy liquid hydrocarbon fuels
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作者 Neng Gong Quanzheng Deng +4 位作者 Yujiao Wang Zitao Wang Lu Han Peng Wu Shun'ai Che 《Chinese Journal of Catalysis》 2025年第1期246-258,共13页
Designing Fischer-Tropsch synthesis(FTS)catalysts to selectively produce liquid hydrocarbon fuels is a crucial challenge.Herein,we selectively introduced Co nanoparticles(NPs)into the micropores and mesopores of an or... Designing Fischer-Tropsch synthesis(FTS)catalysts to selectively produce liquid hydrocarbon fuels is a crucial challenge.Herein,we selectively introduced Co nanoparticles(NPs)into the micropores and mesopores of an ordered mesoporous MFI zeolite(OMMZ)through impregnation,which controlled the carbon number distribution in the FTS products by tuning the position of catalytic active sites in differently sized pores.The Co precursors coordinated by acetate with a size of 9.4×4.2×2.5Åand by 2,2'-bipyridine with a size of 9.5×8.7×7.9Å,smaller and larger than the micropores(ca.5.5Å)of MFI,made the Co species incorporated in OMMZ's micropores and mesopores,respectively.The carbon number products synthesized with the Co NPs confined in mesopores were larger than that in micropores.The high jet and diesel selectivities of 66.5%and 65.3%were achieved with Co NPs confined in micropores and mesopores of less acidic Na-type OMMZ,respectively.Gasoline and jet selectivities of 76.7%and 70.8%were achieved with Co NPs confined in micropores and mesopores of H-type OMMZ with Brönsted acid sites,respectively.A series of characterizations revealed that the selective production of diesel and jet fuels was due to the C-C cleavage suppressing of heavier hydrocarbons by the Co NPs located in mesopores. 展开更多
关键词 Fischer-Tropsch synthesis Heavy liquid hydrocarbon fuel Co nanoparticle Ordered mesoporous MFI zeolite C-C cleavage
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原位晶化法合成大孔-微孔MFI型分子筛 被引量:2
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作者 朱绍林 孙明慧 +4 位作者 刘湛 余申 吕佳敏 李小云 陈丽华 《应用化工》 CAS CSCD 北大核心 2024年第1期25-30,共6页
使用单分散纳米级二氧化硅小球(500 nm)作为硅源和大孔模板,以四丙基氢氧化铵为微孔模板,通过“溶解-重结晶”过程原位形成大孔结构,得到大孔-微孔纯硅Silicate-1分子筛(MFI晶型),大孔孔径为150~350 nm,比表面积为350 m^(2)/g,总孔体积... 使用单分散纳米级二氧化硅小球(500 nm)作为硅源和大孔模板,以四丙基氢氧化铵为微孔模板,通过“溶解-重结晶”过程原位形成大孔结构,得到大孔-微孔纯硅Silicate-1分子筛(MFI晶型),大孔孔径为150~350 nm,比表面积为350 m^(2)/g,总孔体积为0.24 cm^(3)/g。并探索了晶化时间、乙醇助剂、干胶干燥条件、微孔模板剂用量及大孔模板尺寸等合成条件对大孔-微孔纯硅Silicate-1分子筛晶化的影响。在此基础上,进一步在纯硅分子筛骨架中引入铝原子,得到大孔-微孔ZSM-5分子筛。 展开更多
关键词 二氧化硅小球 蒸汽辅助晶化 原位晶化 大孔-微孔结构 MFI型分子筛
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应对市场需求变化的灵活高效催化裂化工艺技术研究与工业实践 被引量:7
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作者 王启飞 白旭辉 +1 位作者 许友好 于福东 《石油炼制与化工》 CAS CSCD 北大核心 2024年第7期1-7,共7页
能源结构调整关头,成品油和化工产品市场需求量和价格呈现正弦型波动,现有炼油转型技术存在不可逆性,且生产方案不可灵活调整,无法满足市场需求。在微观尺度调控单分子和双分子反应路径是解决催化裂化工艺由炼油向化工转型发展缺乏灵活... 能源结构调整关头,成品油和化工产品市场需求量和价格呈现正弦型波动,现有炼油转型技术存在不可逆性,且生产方案不可灵活调整,无法满足市场需求。在微观尺度调控单分子和双分子反应路径是解决催化裂化工艺由炼油向化工转型发展缺乏灵活性问题的有效方法,提出双分子反应指数可以作为单分子和双分子反应的发生比例量度,发现反应温度和分子筛催化剂类型是影响液化气和汽油产率的两个显著变量。试验结果显示:转化率相近时,530℃条件下Y分子筛催化剂作用下的汽油和(丙烯+丁烯)产率分别为47.55%和13.31%,580℃条件下MFI分子筛催化剂作用下的汽油和(丙烯+丁烯)产率分别为22.05%和31.45%;得到反应温度和催化剂类型比例与目标产物产率的关系,提出工业装置生产方案灵活切换调整思路,形成灵活高效催化裂化工艺。工业应用结果显示:数周内完成(丙烯+丁烯)与成品油的生产方案切换,生产方案灵活,为低成本渐进式转型发展提供了技术思路。 展开更多
关键词 单分子反应 双分子反应 双分子反应指数 催化裂化 Y分子筛 MFI分子筛
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