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China Petroleum Processing & Petrochemical Technology 2016年第2期18卷 52-56页

作者： Cheng Zhilin qin xixi qin Dunzhong College of Chemistry and Chemical Engineering Yangzhou University Yangzhou 225002 Jiangsu Sinvochem Company Yangzhou 211900

The paper was aimed at the PMMA/HNTs composite nanofibers with well enhanced mechanical properties prepared by electrospinning technique for the first time. A series of characterizations were used to illustrate the structure and properties of the composite nanofibers by SEM, XRD, FTIR and DSC techniques. The effect of the PMMA/HNTs composite nanofibers in relationship to the mass percentage of HNTs was investigated. The results indicated that HNTs wrapped in polymer matrix were highly oriented and dispersed by the electrospinning technique, resulting in improved thermal stability of the polymer. Moreover, the mechanical properties of the PMMA/HNTs composite nanofibers which were dependent on HNTs mass content were measured, and good enhanced mechanical properties were obtained.

关键词： PMMA HNTs composite nanofibers electrospinning

Preparation and Mechanical Properties of PAN/HNTs Composite Nanofibers

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China Petroleum Processing & Petrochemical Technology 2017年第1期19卷 92-98页

作者： Liu Zan qin xixi qin Dunzhong Cheng Zhilin School of Chemistry and Chemical Engineering Yangzhou University Yangzhou 225002 Jiangsu Sinvochem Company Yangzhou 225002

The enhanced composite nanofibers have attracted great attention for application in recent years. The electrospinning technique was considered to be a prospective production pattern for them. This paper provided a promising technique to prepare the polyacrylonitrile （PAN）/halloysite nanotube （HNT） composite nanofbers by using the electrospinning method. The PAN/HNTs composite nanofbers with well enhanced performance were successfully fabricated from a mixture of PAN/DMF/HNTs dispersion solution processed by the electrospinning technique. For achieving good dispersion in PAN polymer, the highly dispersed HNTs were obtained by using polycarboxylate modifcation employing the in-situ spray-drying method. The structure and properties of the composite nanofbers were characterized by TEM, XRD, EDX, IR, and DSC techniques. The obtained PAN/HNTs composite nanofbers with different HNTs contents were about 300-500 nm in diameter. In addition, the mechanical properties of PAN/HNTs composite nanofbers were tested, which exhibited an excellently enhanced performance.

关键词： PAN HNTs composite nanofber electrospinning

Research and Analysis of School-selection Fee in China

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Chinese Business Review 2005年第7期4卷 79-81页

作者： xixi qin Xuan Wang Wuhan University

Senior high school education belongs to semipublic goods in China as the payout of senior high school is provided by public finance and market. Some key high schools ask for very high school-selection fee, which is a great burden on many families. And higher and higher school-selection fee is against social justice and endangers social environment＇s harmonious and steady. The paper analyzes the reasons and influences of school-selection fee, and points out some suggestions.

关键词： school-selection fee semipublic goods education resource system

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基于准稠密匹配的结构化场景三维重建

计算机辅助设计与图形学学报 2011年第5期23卷 849-854页

作者：李晓明秦茜茜太原科技大学计算机科学技术学院太原030024 山西大学数学科学学院太原030006

传统的准稠密对应点匹配算法大都是针对一般场景开发的,未考虑场景的结构特点.为此,针对结构化场景提出一种基于平面单应约束的准稠密匹配方法.首先采用基于仿射不变量的方法检测和匹配稀疏平面种子区域,然后根据平面间的几何约束和对... 详细信息

传统的准稠密对应点匹配算法大都是针对一般场景开发的,未考虑场景的结构特点.为此,针对结构化场景提出一种基于平面单应约束的准稠密匹配方法.首先采用基于仿射不变量的方法检测和匹配稀疏平面种子区域,然后根据平面间的几何约束和对应点相似性约束,利用区域增长的方法实现准稠密扩散匹配.最优种子区域优先扩散策略的应用大大减小了初始错误种子区域对扩散过程的影响,而对不可靠扩散点的后处理也有效地提高了最终三维重建的精度.实验结果表明,相比传统的准稠密匹配方法,对于结构化场景,采用文中方法更加精确和稳定.

关键词：准稠密匹配平面映射鱼眼图像三维重建基于图像的渲染

Atomic processing of two-dimensional amorphous carbon

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Science China Materials 2024年第12期67卷 4059-4064页

作者： Yunna Guo Hantao Cui Zhangran Ye xixi qin Peng Jia Lei Deng Chongchong Ma Chao Tai Liqiang Zhang Bin Wen Clean Nano Energy Center State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004China Center for Extreme Deformation Research State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004China

Two-dimensional amorphous carbon(2DAC)materials possess characteristics such as high conductivity,high flexibility,and chemical stability,making them promising for applications in electronics,sensors,catalysts,superconductors,energy storage,and energy ***,it is still a challenge to directly synthesize 2DAC till ***,many controversies exist in their formation process and ***,this article utilizes a top-down etching method to prepare 2DAC in environmental transmission electron microscope(ETEM).By employing electron beam irradiation combined with heating at 650°C in an oxygen atmosphere(0.01 mbar),controllable fabrication of 2DAC is *** this process,the raw diamond sheet first transforms into graphite,and as the reaction goes on,the amount of graphite increases,eventually transitioning into ***-principles calculations indicate that it is an energy-favorable process from diamond to *** there is an energy barrier for graphite-to-amorphous carbon transition,electron beam irradiation induces numerous defects that can overcome this *** method not only fabricates 2DAC with atomic precision but also provides in-situ analysis of its formation *** research findings contribute to a fundamental understanding of the formation process of 2DAC and offer new insights for the preparation of 2D ultrathin amorphous materials.

关键词： two-dimensional amorphous carbon(2DAC) topdown etching diamond

1株食源性蜡样芽胞杆菌分离株的分子特征毒性及耐药性研究

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中国食品卫生杂志 2023年第8期35卷 1183-1191页

作者：秦希曦李文张雯岳楠马红梅曾瑾马臣杰宁夏大学生命科学学院宁夏银川750021 宁夏回族自治区兽药饲料监察所宁夏银川750001

目的研究株蜡样芽胞杆菌SCY分离株的毒力和耐药性。方法使用选择性培养基从银川市某餐厅鱼肉菜肴中培养分离获得蜡样芽胞杆菌SCY分离株,经23S rRNA基因PCR测序鉴定后,通过二代全基因组测序技术分析SCY分离株的基因组特征,进而分别采用... 详细信息

目的研究株蜡样芽胞杆菌SCY分离株的毒力和耐药性。方法使用选择性培养基从银川市某餐厅鱼肉菜肴中培养分离获得蜡样芽胞杆菌SCY分离株,经23S rRNA基因PCR测序鉴定后,通过二代全基因组测序技术分析SCY分离株的基因组特征,进而分别采用免疫组化技术和药敏纸片实验研究SCY分离株的毒性和耐药性。结果SCY分离株的基因组大小为5.82 Mb,编码基因个数为5767,编码区总长度占全基因组的85.50%。SCY分离株基因组中共含有11个基因岛、16个CRISPR和5个前噬菌体;其中,SCY编码基因分别在PHI和VFDB毒力因子数据库中注释到了14个和62个毒力基因(Identiy>80,Evalue<0.05),在CARD耐药数据库中注释到了215个耐药基因(Best Hit evalue<0.05)。小鼠肠道组织切片免疫组化结果表明,炎性因子IL-1β、CASP1和Nlrp3的表达水平发生差异显著性上调。22种细菌抗生素药敏纸片试验结果显示,SCY分离株对氯霉素、克林霉素等高度敏感,对四环素、头孢唑啉、头孢哌酮、氨苄青霉素表现为中介,对青霉素、苯唑西林、哌拉西林、杆菌肽、头孢他啶等10种抗生素表现为耐药,SCY分离株多重耐药情况较为严重。结论本研究发现的SCY分离株属于肠毒株,携带多种肠毒素毒力基因,且具有典型的多重耐药特征。研究结果为揭示蜡样芽胞杆菌分离株的致病机制提供参考依据。

关键词：蜡样芽胞杆菌分离株毒性毒力基因耐药性

Nb2O5半导体纳米材料形貌调控与气体敏感性能研究

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化工新型材料 2019年第8期47卷 53-57页

作者：白宇舟郑哲蔚石佳凝易哲涵冯伟秦茜茜季惠明天津大学材料科学与工程学院先进陶瓷及加工技术教育部重点实验室

以NH4HF2、氧化铌和氨水为原料,采用水热制备法,通过精确调控Nb前驱体溶液的pH,实现了Nb2O5纳米材料的形貌调控,制备得到了六方相Nb2O5纳米球及纳米棒材料。采用X射线衍射仪、扫描电子显微镜、比表面积和孔径分布分析仪对Nb2O5纳米材料... 详细信息

以NH4HF2、氧化铌和氨水为原料,采用水热制备法,通过精确调控Nb前驱体溶液的pH,实现了Nb2O5纳米材料的形貌调控,制备得到了六方相Nb2O5纳米球及纳米棒材料。采用X射线衍射仪、扫描电子显微镜、比表面积和孔径分布分析仪对Nb2O5纳米材料的物相、形貌及比表面积进行了表征分析;采用静态配气法对其进行气敏性能测试,讨论了形貌对Nb2O5纳米材料气敏性能的影响。结果表明:Nb2O5纳米球与纳米棒均对丙酮表现出良好的选择性。与Nb2O5纳米球相比,Nb2O5纳米棒表现出更高的气敏响应及更短的响应时间和恢复时间:对50×10^-6(体积分数,下同)丙酮气体,Nb2O5纳米棒的气敏响应可达3.15,响应时间为7s,恢复时间为10s;Nb2O5纳米棒对丙酮表现出更好的气敏性能应归因于其具有更大的比表面积。

关键词：氧化铌气敏纳米棒水热法

Secure Beamforming Design for SWIPT in Cooperative D2D Communications

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China Communications 2017年第1期14卷 20-33页

作者： Li Jiang Cheng qin xixi Zhang Hui Tian State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunicationsand Science and Technology on Information Transmission and Dissemination in Communication Networks LaboratoryBeijing100876China

In device-to-device(D2D) communications, device terminal relaying makes it possible for devices in a network to function as transmission relays for each other to enhance the spectral efficiency. In this paper we consider a cooperative D2D communication system with simultaneous wireless information and power transfer(SWIPT). The cooperative D2D communication scheme allows two nearby devices to communicate with each other in the licensed cellular bandwidth by assigning D2D transmitters as half-duplex(HD) relay to assists cellular downlink transmissions. In particular, we focus on secure information transmission for the cellular users when the idle D2D users are the potential eavesdroppers. We aim to design secure beamforming schemes to maximize the D2D users data rate while guaranteeing the secrecy rate requirements of the cellular users and the minimum required amounts of power transferred to the idle D2D users. To solve this non-convex problem, a semi-definite programming relaxation(SDR) approach is adopted to obtain the optimal solution. Furthermore, we propose two suboptimal secure beamforming schemes with low computational complexity for providing secure communication and efficient energy transfer. Simulation results demonstrate the superiority of our proposed scheme.

关键词： device-to-device(D2D) communications half-duplex relaying physical layer security secure beamforming simultaneous wireless information and power transfer

A pH-responsive mesoporous silica nanoparticles-based drug delivery system with controlled release of andrographolide for OA treatment

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Regenerative Biomaterials 2021年第4期8卷 1-10页

作者： Mingwei He Zainen qin Xiaonan Liang xixi He Bikang Zhu Zhenhui Lu qingjun Wei Li Zheng Guangxi Engineering Center in Biomedical Material for Tissue and Organ Regeneration The First Affiliated Hospital of Guangxi Medical UniversityNo.22 Shuangyong RoadQingxiu DistrictNanning 530021China Guangxi Collaborative Innovation Center for Biomedicine The First Affiliated Hospital of Guangxi Medical UniversityNo.22 Shuangyong RoadQingxiu DistrictNanning 530021China Department of Orthopaedics Trauma and Hand Surgery The First Affiliated Hospital of Guangxi Medical UniversityNo.6 Shuangyong RoadQingxiu DistrictNanning 530021China

Andrographolide(AG)has favorable anti-inflammatory and antioxidative ***,it has low bioavailability due to high lipophilicity and can be easily cleared by the synovial fluid after intra-articular injection,leading to low therapeutic efficiency in osteoarthritis(OA).Herein,we designed a nano-sized pH-responsive drug delivery system(DDS)for OA treatment by using modified mesoporous silica nanoparticles(MSNs)with pH-responsive polyacrylic acid(PAA)for loading of AG to form AG@MSNs-PAA *** nanoparticles have uniform size(120 nm),high drug loading efficiency(22.3860.71%)and pH-responsive properties,beneficial to sustained release in OA *** with AG,AG@MSNs-PAA showed enhanced antiarthritic efficacy and chondro-protective capacity based on IL-1b-stimulated chondrocytes and anterior cruciate ligament transection-induced rat OA model,as demonstrated by lower expression of inflammatory factors and better prevention of proteoglycan ***,the AG@MSNs-PAA nanoplatform may be developed as a promising OA-specific and on-demand DDS.

关键词： Osteoarthritis mesoporous silica nanoparticles polyacrylic acid pH-response andrographolide

In situ decorating the surface and interlayer of montmorillonite with Co_(0.5)Ni_(0.5)Fe_(2)O_(4) nanoparticles: A sustainable, biocompatible colorimetric platform for H_(2)O_(2) and acetylcholine

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Nano Research 2022年第10期15卷 9319-9326页

作者： xixi Zhu Hongyu Li Tao Wu Hui Zhao Kaili Wu Wenjing Xu Fengjuan qin Wenxing Chen Jinlong Zheng qingyun Liu College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdao 266590China Beijing Advanced Innovation Center for Materials Genome Engineering Shunde Graduate SchoolSchool of Mathematics and PhysicsUniversity of Science and Technology BeijingBeijing 100083China Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

Originated from nature and used for nature is a way of sustainable *** this work,montmorillonite(MMT),a natural two-dimensional(2D)layered mineral,the surface and interlayer of which were nano-decorated by chemical synthesis technique was applied in biological detection *** ferrite(Co_(0.5)Ni_(0.5)Fe_(2)O_(4))was anchored on the surface and intercalated in the interlayer of montmorillonite,which served as a competitive candidate of enzyme *** test toward HUVEC and Hela cells verified the good biocompatibility of Co_(0.5)Ni_(0.5)Fe_(2)O_(4)-MMT,guaranteeing its safety in biological *** on the peroxidase-like activity of Co_(0.5)Ni_(0.5)Fe_(2)O_(4)-MMT,a colorimetric sensing platform for H_(2)O_(2) was established by a facile mix-anddetect approach with the detection limit of 0.565μM(3σ/slope).It was implied that the peroxidase-like activity of Co_(0.5)Ni_(0.5)Fe_(2)O_(4)-MMT was originated from generation of·OH and·O_(2)–produced from catalytic decomposition process of H_(2)O_(2).Coupled with cascaded catalytic reactions of ACh,a facile and efficient sensing platform for ACh with satisfactory anti-interference ability was ***,all these remarkable features highlighted the superiority of Co_(0.5)Ni_(0.5)Fe_(2)O_(4)-MMT,and endowed it with a powerful competitiveness in the fields of environmental assessing,biosensing,and disease monitoring.

关键词： montmorillonite colorimetric assays hydrogen peroxide peroxidase-like activity nanozymes