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Frontiers of Information Technology & Electronic Engineering 2021年第4期22卷 471-487页

作者： peize ZHANG Haiming WANG Wei HONG State Key Laboratory of Millimeter Waves Southeast UniversityNanjing 210096China Purple Mountain Laboratories Nanjing 211111China

The deployment of millimeter-wave(mmWave)cellular systems in dense urban environments with an acceptable coverage and cost-efficient transmission scheme is essential for the rollout of fifth-generation and beyond *** this paper,cluster-based analysis of mmWave channel characteristics in two typical dense urban environments is ***,radio propagation measurement campaigns are conducted in two identified mmWave bands of 28 and 39 GHz in a central business district and a dense residential *** customdesigned channel sounder supports high-efficiency directional scanning sounding,which helps collect sufficient data for statistical channel ***,using an improved auto-clustering algorithm,multipath clusters and their scattering sources are *** appropriate measure for inter-and intra-cluster characteristics is provided,which includes the cluster number,the Ricean K-factor,root-mean-squared(RMS)delay spread,RMS angular spread,and their *** of these parameters across two mmWave bands for both line-of-sight(LoS)and non-light-of-sight(NLoS)links are *** shed light on the blockage effects,detailed analysis of the propagation mechanisms corresponding to each NLoS cluster is provided,including reflection from exterior walls and diffraction over building corners and ***,the results show that the cluster-based analysis takes full advantage of mmWave beamspace channel characteristics and has further implications for the design and deployment of mmWave wireless networks.

关键词： Millimeter-wave communication Clustering Diffraction Multipath channels Propagation measurement

A thioether-functionalized pyrene-based covalent organic framework anchoring ultrafine Au nanoparticles for efficient photocatalytic hydrogen generation

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Chinese Journal of Catalysis 2022年第10期43卷 2699-2707页

作者： Zhiming zhou Chuanbiao Bie peize Li Bien Tan Yan Shen Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074HubeiChina Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430074HubeiChina

Covalent organic frameworks(COFs)have lately emerged as a blooming class of potential materials for photocatalytic water splitting because of their high crystallinity,huge surface areas,and structural ***,the photocatalytic performance for most pure COFs face some limitations factors,such as the significant recombination of photogenerated carriers and slow charge ***,a novel thioether-functionalized pyrene-based COF(S_(4)-COF)was effectively produced and chosen as a support for the immobilization of ultrafine gold nanoparticles(Au NPs).S_(4)-COF photocatalyst with Au as cocatalyst demonstrates remarkable photocatalytic activity with a H_(2) generation rate of 1377μmol g^(−1) h^(−1) under visible light(>420 nm),which is ca.4.5-fold increase comparing to that of pure S_(4)-COF(302μmol g^(−1) h^(−1)).Au NPs anchored on S_(4)-COF possess an ultrafine size distribution ranging from 1.75 to 6.25 nm with an average size centered at 3.8 nm,which benefits from the coordination interaction between thioether groups and ***,the produced Au@S_(4)-COF can generate a stable photocatalytic H_(2) generation during the four recycles and preserve its crystallinity structure after the stability *** Au NPs anchored on the S_(4)-COF photocatalyst can greatly accelerate the separation of photogenerated carriers and increase charge transfer because of the combined function of Au NPs and thioether *** a method can not only prevent the aggregation of Au NPs onto thioether-containing COFs to achieve long-term photostability but also allow uniform dispersion for an ordered structure of *** work provides a rational strategy for designing and preparing COF-based photocatalysts for solar-driven H_(2) production.

关键词： Photocatalysis Covalent organic framework Thioether functionalization Gold nanoparticle Coordination interaction Photogenerated carrier separation

Sub-5 nm bilayer GaSe MOSFETs towards ultrahigh on-state current

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Frontiers of physics 2024年第5期19卷 143-151页

作者： Xueping Li Xiaojie Tang Zhuojun Wang peize Yuan Lin Li Chenhai Shen Congxin Xia College of Electronic and Electrical Engineering Henan Normal UniversityXinxiang 453007China Henan Key Laboratory of Optoelectronic Sensing Integrated Application Xinxiang 453007China School of Physics Henan Normal UniversityXinxiang 453007China

Dielectric engineering plays a crucial role in the process of device *** we investigate the electrical properties of bilayer GaSe metal-oxide-semiconductor field-effect transistors(MOSFETs),considering hetero-gate-dielectric construction,dielectric materials and GaSe stacking *** results show that device performance strongly depends on the dielectric constants and locations of *** highk dielectric is placed close to the drain,it behaves with a larger on-state current(I_(on))of 5052μA/μm when the channel is 5 ***,when the channel is 5 nm and insulator is HfO_(2),the largest I_(on) is 5134μA/μm for devices with AC stacking GaSe *** particular,when the gate length is 2 nm,it still meets the HP requirements of ITRS 2028 for the device with AA stacking when high-k dielectric is ***,the work provides guidance to regulate the performance of the two-dimensional nanodevices by dielectric engineering.

关键词： GaSe stacking pattern metal-oxide-semiconductor field-effect transistors(MOSFETs) ultrahigh on-state current dielectric engineering

Two dimensional GeO_(2)/MoSi_(2)N_(4)van der Waals heterostructures with robust type-Ⅱ band alignment

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Frontiers of physics 2023年第1期18卷 115-122页

作者： Xueping Li peize Yuan Lin Li Ting Liu Chenhai Shen Yurong Jiang Xiaohui Song Congxin Xia College of Electronic and Electrical Engineering Henan Normal UniversityXinxiang 453007China Department of Physics Henan Normal UniversityXinxiang 453007China Henan Key Laboratory of Optoelectronic Sensing Integrated Application Henan Normal UniversityXinxiang 453007China

Constructing two-dimensional(2D)van der Waals heterostructures(vdWHs)can expand the electronic and optoelectronic applications of 2D ***,the work on the 2D vdWHs with robust band alignment is still ***,we employ a global structure search approach to construct the vdWHs with monolayer MoSi_(2)N_(4)and widebandgap GeO_(2).The studies show that the GeO_(2)/MoSi_(2)N_(4)vdWHs have the characteristics of direct structures with the band gap of 0.946 eV and typeII band alignment with GeO_(2)and MoSi_(2)N_(4)layers as the conduction band minimum(CBM)and valence band maximum(VBM),***,the direct-to-indirect band gap transition can be achieved by applying biaxial *** particular,the 2D GeO_(2)/MoSi_(2)N_(4)vdWHs show a robust type-II band alignment under the effects of biaxial strain,interlayer distance and external electric *** results provide a route to realize the robust type-II band alignment vdWHs,which is helpful for the implementation of optoelectronic nanodevices with stable characteristics.

关键词： van der Waals heterostructures wide gap material global structure search robust type-II band alignment

Site-directed mutagenesis of bifunctional riboflavin kinase/FMN adenylyltransferase via CRISPR/Cas9 to enhance riboflavin production

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Synthetic and Systems Biotechnology 2024年第3期9卷 503-512页

作者： Bing Fu Meng Chen Xianfeng Bao Jiajie Lu Zhiwen Zhu Fuyao Guan Chuyang Yan peize Wang Linglin Fu Ping Yu College of Food Science and Biotechnology Zhejiang Gongshang University149 Jiaogong RoadHangzhouZhejiang Province310035People’s Republic of China College of Forestry Science and Technology Lishui Vocational and Technical College357 Zhongshan Street NorthLishuiZhejiang Province323000People’s Republic of China Lishui Institute for Quality Inspection and Testing 395 Zhongshan StreetLishuiZhejiang Province323000People’s Republic of China

Vitamin B_(2)is an essential water-soluble *** most prokaryotes,a bifunctional enzyme called FAD synthase catalyzes the successive conversion of riboflavin to FMN and *** this study,the plasmid pNEW-AZ containing six key genes for the riboflavin synthesis was transformed into strain R2 with the deleted FMN riboswitch,yielding strain *** R5 strain could produce 540.23±5.40 mg/L riboflavin,which was 10.61%higher than the R4 strain containing plasmids pET-AE and pAC-Z harboring six key *** further enhance the production of riboflavin,homology matching and molecular docking were performed to identify key amino acid residues of FAD *** point mutation sites were *** comparing riboflavin kinase activity,mutations of T203D and N210D,which respectively decreased by 29.90%and 89.32%compared to wild-type FAD synthase,were selected for CRISPR/Cas9 gene editing of the genome,generating engineered strains R203 and ***-AZ was transformed into R203,generating R6.R6 produced 657.38±47.48 mg/L riboflavin,a 21.69%increase compared to *** study contributes to the high production of riboflavin in recombinant *** BL21.

关键词： Vitamin B_(2) FAD synthase Escherichia coli BL21 Riboflavin kinase CRISPR/Cas9

基于新能源低碳背景的汽车电热相变储能系统的动态储热性能分析

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储能科学与技术 2023年第12期12卷 3892-3894页

作者：闫培泽濮阳职业技术学院机电与汽车工程学院河南濮阳457000

汽车电热相变储能系统实时储热功率超过预设功率值,会造成电力资源过度转化,导致能源浪费。对此设计新能源低碳汽车电热相变储能系统储热性能动态优化方法。分析新能源低碳机制的可行性,构建电热储能的目标协调函数,设定相变储能系统有... 详细信息

汽车电热相变储能系统实时储热功率超过预设功率值,会造成电力资源过度转化,导致能源浪费。对此设计新能源低碳汽车电热相变储能系统储热性能动态优化方法。分析新能源低碳机制的可行性,构建电热储能的目标协调函数,设定相变储能系统有功功率阈值,配合变压器与电加热器组之间的功率转换关系,求解动态储热约束条件,完成对汽车电热相变储能系统的动态储热性能的分析。实验证明,上述方法可以避免出现实时储热功率超过预设功率值的情况。

关键词：新能源低碳电热相变储能系统动态储热

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监察对象应然范围的理论逻辑与识别路径

云南师范大学学报（哲学社会科学版） 2023年第6期55卷 83-95页

作者：吴沛泽云南财经大学法政学院云南昆明650051

对国家监察对象的范围界定是监察法治运行体系的实践基础。一方面,传统的监察对象认定方案尚不能满足识别准确性、覆盖全面性与操作有效性等价值目标;另一方面,《实施条例》对监察对象的细化也引领着学理观点的适时修正。上述两点原因... 详细信息

对国家监察对象的范围界定是监察法治运行体系的实践基础。一方面,传统的监察对象认定方案尚不能满足识别准确性、覆盖全面性与操作有效性等价值目标;另一方面,《实施条例》对监察对象的细化也引领着学理观点的适时修正。上述两点原因是“后监察法”时代中再论监察对象应然范围的现实基础。监察对象认定标准的建构需要对《监察法》的规范文本进行再解读,明确总则“公职人员”与分则“公职人员”“有关人员”各自的实质内涵。同时应确立“行为属性”的唯一内核地位,摒弃“身份属性”对认定监察对象的直接或间接影响。基于对《监察法》及《实施条例》的规范分析,监察对象的界定应采取“管理职能权利来源的国家代表性”标准。“管理职能”“权力来源”与“国家代表性”分别对应着“行使公权力”的行为方式、法律评价与本质特征3个方面,是对“行使公权力”这一实质标准的具体化。不同法域下监察对象的身份衔接存在识别过程与转换适用两个环节,对此应树立不同的处理思路以促进监察法与其他法律体系的融贯与协调。

关键词：监察对象实施条例行使公权力身份衔接

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玉林铁路枢纽客运系统布局方案研究

铁道运输与经济 2020年第9期42卷 117-122页

作者：石培泽中铁第一勘察设计院集团有限公司线路运输院陕西西安710043

玉林铁路枢纽作为玉林市重要的交通设施,是连接粤港澳大湾区和北部湾城市群的重要铁路枢纽。在阐述玉林铁路枢纽现状和客运系统规划的基础上,分别就玉林铁路枢纽客运站布局、新建客运站选址和站场布置3个方面进行深入分析,从中选出最佳... 详细信息

玉林铁路枢纽作为玉林市重要的交通设施,是连接粤港澳大湾区和北部湾城市群的重要铁路枢纽。在阐述玉林铁路枢纽现状和客运系统规划的基础上,分别就玉林铁路枢纽客运站布局、新建客运站选址和站场布置3个方面进行深入分析,从中选出最佳的玉林铁路枢纽客运系统布局方案。合理确定玉林铁路枢纽客运系统布局方案,可以减少玉林市旅客的旅行时间,提升玉林铁路枢纽的客运能力,增强玉林市在广西东部的辐射效应,将玉林市打造成为承接粤港澳大湾区和北部湾城市群的综合交通枢纽城市,有效提升玉林市的综合实力。

关键词：玉林铁路枢纽客运系统线路布局车站选址站场布置方案比选

基于有限元模拟的汽车专用异形螺母冷镦缺陷分析与改进

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锻压技术 2022年第12期47卷 21-26页

作者：闫培泽濮阳职业技术学院机电与汽车工程学院河南濮阳457000

针对汽车专用异形螺母在多工位冷镦生产中出现的局部材料折叠问题,提出了采用Deform软件对异形螺母进行成形仿真。由各工位零件的检验结果可知,折叠缺陷最先出现在薄壁成形工位,并对其进行有限元分析验证,结果表明:折叠缺陷是由于模具... 详细信息

针对汽车专用异形螺母在多工位冷镦生产中出现的局部材料折叠问题,提出了采用Deform软件对异形螺母进行成形仿真。由各工位零件的检验结果可知,折叠缺陷最先出现在薄壁成形工位,并对其进行有限元分析验证,结果表明:折叠缺陷是由于模具结构设计不当而引起材料对流造成的。首先,根据原方案的材料流动规律对模具结构提出了改进方案,解决了材料折叠问题;同时,为确保整个成形工艺的可靠性,对后续工位的模具结构进行了改进和模拟验证。最后,基于模拟结果对改进后的模具进行了制造,并通过多工位冷镦机进行了试模加工。结果显示,薄壁成形工位及后续工位均未出现折叠缺陷,与仿真结果相符,这表明有限元技术能准确预测工艺缺陷,有效解决企业的实际难题。

关键词：异形螺母多工位冷镦材料折叠模具结构 Deform软件

激冷Ti-46Ni合金薄带的组织、相变和形状记忆效应

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稀有金属材料与工程 2017年第9期46卷 2445-2448页

作者：贺志荣刘琳周超吴佩泽邹启明陕西理工大学陕西汉中723001

用激冷甩带法制备了Ti-46Ni合金薄带,用扫描电子显微镜、X射线衍射仪、示差扫描热分析仪和弯曲试验研究了合金薄带的组织特征、相变行为和形状记忆效应。结果表明,铸态及400~600℃退火态Ti-46Ni合金薄带的显微组织形态呈树枝状,晶粒细小... 详细信息

用激冷甩带法制备了Ti-46Ni合金薄带,用扫描电子显微镜、X射线衍射仪、示差扫描热分析仪和弯曲试验研究了合金薄带的组织特征、相变行为和形状记忆效应。结果表明,铸态及400~600℃退火态Ti-46Ni合金薄带的显微组织形态呈树枝状,晶粒细小,由B19?马氏体和B2母相组成;在冷却、加热过程中,该合金薄带发生一阶段马氏体相变;铸态和退火态Ti-46Ni合金薄带均具有良好的形状记忆效应。

关键词： Ti-46Ni合金形状记忆合金薄带组织相变形状记忆效应