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Journal of Advanced Ceramics 2016年第4期5卷 298-307页

作者： Hongfang SHEN Youjun LU Yanmin WANG Zhidong PAN Guozhong CAO Xianghui YAN Guoli FANG School of Materials Science and Engineering South China University of Technology Guangzhou 510640 ChinaSchool of Materials Science and Engineering Beifang University of Nationalities Yinchuan 750021 China School of Materials Science and Engineering Beifang University of Nationalities Yinchuan 750021 China School of Materials Science and Engineering South China University of Technology Guangzhou 510640 China Department of Materials Science and Engineering University of Washington Seattle WA 98195 USA

SrTiO3 nanoparticle (NP) photocatalyst was synthesized with a facile and environmentalfriendly hydrothermal method using tetrabutyltitanate, strontium oxide, and ethanolamine as precursors at low temperature without alkali as mineralizer for the first time. The SrTiO3 nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), and N2 Brunauer–Emmett–Teller (BET) method. The SrTiO3 catalyst synthesized at 120 °C (STO-120) exhibited the highest photocurrent intensity among the samples synthesized at different hydrothermal temperatures. The high photocatalytic performance of STO-120 was mainly attributed to the more homogeneous and minimum nanoparticle size, the highest surface area, and the maximum light absorption property among the four different samples. This work presented an applicable and facile method to fabricate a highly active and stable SrTiO3 photocatalyst for organic pollutant degradation.

关键词： polyhedral SrTiO 3 hydrothermal synthesis low temperature photocurrent property photocatalytic activity stability

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基于改进带宽自适应ACMD的信号分离方法

雷达科学与技术 2024年第3期22卷 275-283页

作者：方国俊王国丽邓志安哈尔滨工程大学信息与通信工程学院黑龙江哈尔滨150001 哈尔滨工程大学先进船舶通信与信息技术工业和信息化部重点实验室黑龙江哈尔滨150001

针对复杂电磁环境下出现多个辐射源信号混叠造成的多分量信号分离问题,提出了基于改进带宽自适应线性调频模态分解(ACMD)的信号分离方法。该方法利用频谱集中性指标对各信号分量的瞬时频率进行估计,将估计的瞬时频率值作为改进算法的预... 详细信息

针对复杂电磁环境下出现多个辐射源信号混叠造成的多分量信号分离问题,提出了基于改进带宽自适应线性调频模态分解(ACMD)的信号分离方法。该方法利用频谱集中性指标对各信号分量的瞬时频率进行估计,将估计的瞬时频率值作为改进算法的预设频率;利用递归框架和改进带宽自适应更新方法对各信号分量进行循环迭代;直到剩余信号能量小于阈值,完成所有信号分离。仿真实验表明,该方法能够在复杂电磁环境下分离出多分量信号,相比较已有算法对紧邻信号具有更好的分离性能和抗噪声性能。

关键词：信号分离复杂电磁环境带宽自适应ACMD 频谱集中性指标

电泳烘烤对EP/CF及EP/CF/GF复合材料力学性能的影响

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中国塑料 2024年第3期38卷 1-6页

作者：崔晓凤方梅杜松林张娜黄明高国利许经纬郑州大学材料成型及模具技术教育部重点实验室-橡塑模具国家工程研究中心郑州450002 深圳市银宝山新科技股份有限公司广东深圳518108 常州宏发纵横新材料科技有限公司江苏常州213135

采用真空辅助树脂传递模塑(VARTM)工艺制备了不同铺层方式的碳纤维增强聚合物基复合材料(CFRP):环氧树脂/碳纤维(EP/CF)和环氧树脂/碳纤维/玻璃纤维毡(EP/CF/GF)复合材料,重点研究了不同铺层纤维体系的CFRP渗透率以及电泳烘烤前后的力... 详细信息

采用真空辅助树脂传递模塑(VARTM)工艺制备了不同铺层方式的碳纤维增强聚合物基复合材料(CFRP):环氧树脂/碳纤维(EP/CF)和环氧树脂/碳纤维/玻璃纤维毡(EP/CF/GF)复合材料,重点研究了不同铺层纤维体系的CFRP渗透率以及电泳烘烤前后的力学性能变化,探究了其失效机理。结果表明,[±45°]铺层方式有利于体系中树脂的浸润,且加入GF能够明显提高体系的渗透率;电泳烘烤后,CF[0/90°]、CF[±45°]和CF/GF[±45°]的拉伸强度分别下降了15.65%、12.05%和6.77%,模量分别下降了9.08%、16.39%和10.04%,而CF/GF[0/90°]的拉伸强度和模量则分别提高了7.74%和6.95%;在弯曲性能方面,电泳烘烤后CF[0/90°]、CF/GF[0/90°]、CF[±45°]和CF/GF[±45°]的弯曲强度分别下降了7.62%、8.23%、15.89%和48.39%,模量分别降低了9.23%、3.69%、17.85%和34.38%;而电泳烘烤对4种材料的压缩性能影响较小;电泳后,CF[0/90°]和CF[±45°]的储能模量、损耗模量均有一定幅度提高,CF/GF[0/90°]和CF/GF[±45°]的储能模量、损耗模量均有下降。

关键词：碳纤维增强聚合物真空辅助树脂传递模塑渗透率电泳烘烤

持续气道正压通气治疗慢性高血压合并睡眠呼吸暂停低通气综合征的双胎孕妇3例

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中华围产医学杂志 2024年第3期27卷 241-244页

作者：吕晓王晶玉魏俊杨京晶韩芳刘国莉北京大学人民医院妇产科北京100044 山西省临汾市妇幼保健院妇产科临汾041000 北京大学人民医院呼吸睡眠医学科北京100044

本文报告3例慢性高血压合并阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea-hypopnea syndrome,OSAHS)的双胎孕妇应用持续气道正压通气(continuous positive airway pressure,CPAP)后的母儿结局。3例双胎孕妇均合并慢性高血压... 详细信息

本文报告3例慢性高血压合并阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea-hypopnea syndrome,OSAHS)的双胎孕妇应用持续气道正压通气(continuous positive airway pressure,CPAP)后的母儿结局。3例双胎孕妇均合并慢性高血压;均因夜间有打鼾、呼吸暂停症状,行多导睡眠图监测,诊断为OSAHS。病例1孕28周行CPAP治疗后1个月,血压缓慢升高,伴尿蛋白增加,孕34周并发溶血、肝酶升高、血小板减少综合征剖宫产;病例2孕11周行CPAP治疗,孕期血压平稳,孕37周行剖宫产;病例3孕13周行CPAP治疗4个月后血压升高,尿蛋白阳性,经药物治疗,血压降低,尿蛋白转阴,孕32周因并发胎膜早破行剖宫产,CPAP治疗至分娩,母婴结局良好。由这3例认为,CPAP可能延缓慢性高血压合并OSAHS双胎孕妇孕期血压上升的时间,有助于减少不良母婴结局。

关键词：高血压睡眠呼吸暂停,阻塞性连续气道正压通气妊娠,双胎

Tunable Multicolor Circularly Polarized Luminescence via Co-assembly of One Chiral Electron Acceptor with Various Donors

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CCS Chemistry 2023年第7期5卷 1592-1601页

作者： fang Wang Chengshuo Shen Fuwei Gan guoli Zhang Huibin Qiu School of Chemistry and Chemical Engineering Zhangjiang Institute for Advanced StudyFrontiers Science Center for Transformative MoleculesState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240 Key Laboratory of Specially Functional Polymeric Materials and Related Technology(Ministry of Education) School of Material Science and EngineeringEast China University of Science and TechnologyShanghai 200237

Chiroptical materials with multicolor and signinvertible circularly polarized luminescence(CPL)are important for advanced optical devices and display technologies.Here,a general strategy is developed to generate CPL with highly tunable emission bands and handedness through charge-transfer(CT)complexation and co-assembly of one chiral non-emissive tetranitrofluorene-based acceptor with various achiral purple to blue emissive donors.The resulting assemblies exhibit intense CPL with a rich array of colors(519-668 nm)and prominent dissymmetry factors(|glum|)in the range of 10^(-3)-10^(-2).Notably,the CPL sign can be readily inverted by slightly changing the molecular structure of achiral donors.Single-crystal analysis reveals that the donor and acceptor molecules are alternately and asymmetrically packed in a lamellar fashion through CT interactions,leading to efficient transfer of chirality.Furthermore,the refined packing is mediated by the intensity and manner of CT interactions,rendering an inversion of chirality.The chiral co-assembly not only occurs for planar achiral donor molecules,but is also accessible to nonplanar conjugated molecules such as[4]helicene derivatives.Thus,the CPL feature of the resulting products can be easily and broadly manipulated,aiming at advanced chiroptical systems.

关键词： circularly polarized luminescence charge transfer chirality co-assembly supramolecular chemistry

增强型体外反搏联合药物治疗视网膜中央动脉阻塞的疗效

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西部医学 2024年第4期36卷 539-543页

作者：温舒周翠云蒋洪飞方静刘国立荆门市中心医院眼科湖北荆门448000

目的探讨增强型体外反搏(EECP)联合药物治疗视网膜中央动脉阻塞(CRAO)的疗效。方法选择2020年5月—2021年5月我院诊治的视网膜中央动脉阻塞患者共48例(48眼)作为观察对象,根据治疗方法分为观察组22例(22眼)和对照组26例(26眼),另选取我... 详细信息

目的探讨增强型体外反搏(EECP)联合药物治疗视网膜中央动脉阻塞(CRAO)的疗效。方法选择2020年5月—2021年5月我院诊治的视网膜中央动脉阻塞患者共48例(48眼)作为观察对象,根据治疗方法分为观察组22例(22眼)和对照组26例(26眼),另选取我院同期体检的健康人群20例(20眼)作为阴性对照组。观察组进行4个疗程的EECP联合药物治疗;对照组予单纯药物治疗;阴性对照组予单纯4个疗程EECP治疗。根据治疗前后患者视力、黄斑区血流密度、颈内动脉舒张期末血流速度(EDV)、收缩期峰值血流速度(PSV)及阻力指数(RI)等指标变化,评价及比较疗效。结果观察组总有效率高于对照组(χ^(2)=7.968,P0.05)。病程越短,EECP联合药物治疗效果越好,两者呈高度负相关(r=-0.837,P0.05)。观察组治疗后黄斑区SCP与DCP血流密度较治疗前明显增加,差异均有统计学意义(P0.05)。结论EECP联合药物治疗视网膜中央动脉阻塞,可显著提高CRAO患者的临床疗效,可在临床推广应用。

关键词：增强型体外反搏视网膜中央动脉阻塞疗效评价黄斑区血流密度阻力指数

Electrochemical Studies of Eight New Divalent Transition Metal Benzenesulphonate Ternary Complexes with 1,10-Phenanthroline

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Chemical Research in Chinese Universities 2004年第6期20卷 694-697页

作者： LUYao guoli-ping MAJian-fang YANGJin WUDong-mei FacultyofChemistry NortheastNormalUniversityChangchun130024China CollegeofChemistry＆Pharmocology JiamusiUniversityJiamusi154002China

The electrochemical properties of eight new divalent transition metal benzenesulphonate complexes with 1,10-phenanthroline in different solvents and supporting electrolytes were investigated by means of cyclic voltammetry(CV). Based on the CV data the influences of various coordination modes on the electrochemical behavior of the complexes were discussed. The diffusion coefficient D c and rate constant k s of those complexes in DMF systems were estimated according to CV and the results show that these processes were all quasi-reversible.

关键词： Benzenesulphonate 1,10-Phenanthroline Transition metal complex Cyclic voltammetry

Atomic process of oxidative etching in monolayer molybdenum disulfide

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Science Bulletin 2017年第12期62卷 846-851页

作者： Danhui Lv Hulian Wang Dancheng Zhu Jie Lin guoli Yin fang Lin Ze Zhang ChuanhongJin State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China College of Electronic Engineering South China Agricultural UniversityCuangzhou 510642China Department of Materials Science and Engineering Stanford UniversityStanfordCA 94305USA

The microscopic process of oxidative etching of two-dimensional molybdenum disulfide(2D MoS_2) at an atomic scale is investigated using a correlative transmission electron microscope(TEM)-etching study.MoS_2 flakes on graphene TEM grids are precisely tracked and characterized by TEM before and after the oxidative etching. This allows us to determine the structural change with an atomic resolution on the edges of the domains, of well-oriented triangular pits and along the grain boundaries. We observe that the etching mostly starts from the open edges, grain boundaries and pre-existing atomic defects.A zigzag Mo edge is assigned as the dominant termination of the triangular pits, and profound terraces and grooves are observed on the etched edges. Based on the statistical TEM analysis, we reveal possible routes for the kinetics of the oxidative etching in 2D MoS_2, which should also be applicable for other 2D transition metal dichalcogenide materials like MoSe_2 and WS_2.

关键词：二硫化钼氧化腐蚀原子过程刻蚀透射电子显微镜 TEM分析过渡金属硫化物单层

Synthesis and luminescence of single crystalline Bi_2O_3 nanosheets

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Science China(Technological Sciences) 2011年第1期54卷 19-22页

作者： fang guoli CHEN Guang WANG Xiong LIU JinQiang Engineering Research Center of Materials Behavior and Design Ministry of Education Joint Laboratory ofNanostructured Materials and Technology Nanjing University of Science and Technology Nanjing 210094 China

Single crystalline Bi2O3 nanosheets have been synthesized by the surfactant assisted solvothermal method,using oleic acid and sodium dodecyl benzene sulfonate (SDBS) as compound surfactants. The thickness of Bi2O3 nanosheets is 40–70 nm with a monoclinic crystal structure. High-resolution transmission electron microscopy observation reveals that ( 345 ) lattice plane of the single crystal is parallel to the surface of the nanosheets. The cooperative effect of oleic acid encapsulated SDBS is the key to form single crystalline α-Bi2O3 nanosheets with a preferred growth orientation. An obvious blue shift of the single crystalline Bi2O3 nanosheets with a preferred surface ( 345 ) is observed due to quantum confinement effects in thickness and optical anisotropy.

关键词：氧化铋纳米单晶复合表面活性剂合成十二烷基苯磺酸钠电子显微镜观察发光

Reconstruction Paleoclimate Dased on Sporopollen Record of Re'nacuo Lake,Tibet

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Acta Geologica Sinica(English Edition) 2014年第4期88卷 1239-1251页

作者： LI Hanshi WANG Genhou YUAN guoli fang Bin LUO Tongwei YANG Yongqiang School of the Earth Sciences and Resources China University of Geosciences School of Water Resources and Environment China University of Geosciences Inner Mongolia Mining Exploitation Co.LTD

The sedimentary sequences since 33 ka B.P. to 10 ka B.P. have been established in the Re＇nacuo-Lake, Gaize area of north Tibet, through a study of a lacustrine section. The climate since 33 ka B.P. to 10 ka B.P. may be divided into two cycle include 5 dry phases and 5 moist phases from reconstructing the paleoclimate through a study of sporopollen analysis. It mainly reflects the general regularity of global climatic change through contrasting with the pale environment in northern hemisphere. Our pollen record reveals a regional climate history similar to those from the neighboring sites, including the GISP2, the Guliya ice core and core RM in Zoige, and thus supports the notion that the Qinghai-Tibetan Plateau acts as an important link between climatic events in the North Atlantic realm and the Asian monsoon domain. The response of the Qinghai-Tibet Plateau to the global climatic change is relatively sensitive.

关键词： Tibet lacustrine deposit terrace sporopollen paleoclimate climate change