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雷达旁瓣对消系统角度敏感性分析

电子信息对抗技术 2024年第4期39卷 87-92页

作者：夏碧君朱磊张圣鹋田蕴琦中国电子科技集团公司第二十九研究所成都610036 电磁空间安全全国重点实验室成都610036

旁瓣对消(Sidelobe Cancellation, SLC)作为雷达抗干扰的重要措施之一,在电子对抗中起着重要的作用。为了深入分析不同参量对旁瓣对消性能的影响,越来越多的学者开展旁瓣对消技术研究并根据研究结果进行SLC系统改进或研究攻击旁瓣对消... 详细信息

旁瓣对消(Sidelobe Cancellation, SLC)作为雷达抗干扰的重要措施之一,在电子对抗中起着重要的作用。为了深入分析不同参量对旁瓣对消性能的影响,越来越多的学者开展旁瓣对消技术研究并根据研究结果进行SLC系统改进或研究攻击旁瓣对消系统薄弱环节的新型干扰技术。目前,研究主要针对干扰个数、干扰形式、辅助阵元位置、通道一致性等因素对旁瓣对消系统性能的影响,而分析多干扰角度分布对旁瓣对消系统性能影响的较少。对此,首先建立SLC系统干扰抑制比数学理论模型,然后通过仿真分析多干扰角度分布对旁瓣对消系统性能的影响,为实际分布式支援干扰角度参数优化提供理论支撑。

关键词：雷达旁瓣对消抗干扰干扰角度仿真分析

一种稳健的知识辅助STAP色加载系数优化算法

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电子与信息学报 2016年第8期38卷 1942-1949页

作者：张圣鹋何子述李军赵翔电子科技大学电子工程学院成都611731

色加载知识辅助STAP技术中,需根据先验信息的准确度设置色加载系数。已有的基于色加载矩阵预白化性能评估的色加载系数优化算法(Pre-Whitening,PW)无法评估当前待检测距离单元(CUT)的先验信息准确度,对于杂波先验信息准确度不均匀的场... 详细信息

色加载知识辅助STAP技术中,需根据先验信息的准确度设置色加载系数。已有的基于色加载矩阵预白化性能评估的色加载系数优化算法(Pre-Whitening,PW)无法评估当前待检测距离单元(CUT)的先验信息准确度,对于杂波先验信息准确度不均匀的场景不具有鲁棒性。该文在PW法的基础上提出一种可有效评估CUT单元色加载矩阵性能的稳健色加载系数优化方法(CUT information involved PW,CPW)。CPW法利用部分参考单元样本实现对CUT单元色加载矩阵预白化能力的评估,同时解决了PW法优化结果非单值性的问题。仿真实验讨论了CPW法在不同参考单元样本个数以及不同先验信息准确度条件下的色加载系数优化性能。仿真结果验证了所提方法的有效性及稳健性。

关键词：知识辅助空时自适应处理色加载系数预白化

Bio-Functional Nanodiamond Restorative Materials Containing Bio-Additives: In Vitro Approach

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Open Journal of Stomatology 2015年第5期5卷 117-126页

作者： Victoria Tamara Perchyonok Tatiana Souza Rafael Felliti shengmiao zhang Sias Grobler VTPCHEM PTY LTD Southport Australia S3 Logan Australia Colonia 1181 apt 302 Montevideo Uruguay School of Material Science and Engineering East China University of Science and Technology Shanghai China Oral and Dental Research Institute Faculty of Dentistry University of the Western Cape Cape Town South Africa

Restorative materials in the new era aim to be “bio-active”, bio-functional and long-lasting. As a part of our continuous interest of developing functional dual action restorative materials capable of being “bio-active” functional restorative materials, we designed and evaluated several novel nano-diamond:chitosan containing hydrogels as a prototype of molecular scaffold materials capable of free radical defense action containing propolis extract (antioxidant containing material) from 3 different regions namely, Green Brazilian Propolis, Uruguan Propolis and Australian Propolis. We evaluated the physical properties, bonding to dentin as well as test the bioadhesion of the newly designed materials in order to access the suitability of these prototype materials as suitable restorative materials, evaluated total phenol capacity of the materials as well as free radical defense capacity using BSA protein model as a quick and effective in vitro model. The hydrogels were prepared as previously reported by our protocol. The physico-chemical features including surface morphology (SEM), release behaviors, stability of the antioxidant-chitosan-nanodiamond and the effect of the hydrogels on the shear bond strength of dentin were measured. Structural investigations of the reactive surface of the hydrogel are reported. Bio-adhesive studies were performed in order to assess the suitability of these designer materials. Free radical defence and performance of the materials was evaluated using BSA and Folin Ciocalteu assay. Results: Within the limitations of the study design chitosan-antioxidant hydrogels are suitable materials for functional restorative and periodontal applications in vitro. The addition of propolis extracts nano-diamond chitosan prototype delivery system had a beneficial effect on the design of the hydrogel by increasing bioadhesive properties of the newly prepared hydrogels, increasing free radical defense properties of the biomaterials as well as increasing the d

关键词： Therapeutic Polymers Adhesives Chitosan Hydrogels Propolis Melatonin Naproxen Antimicrobial Dentin Bonding Antioxidants Bioactive

Insights into Functional Tetracycline/Antioxidant Containing Chitosan Hydrogels as Potential Bio-Active Restorative Materials: Structure, Function and Antimicrobial Activity

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Open Journal of Stomatology 2014年第3期4卷 99-108页

作者： Victoria Tamara Perchyonok shengmiao zhang Nicki Basson Sias Grobler Theunis Oberholzer Ward Massey Oral and Dental Research Institute Faculty of Dentistry University of the Western Cape Cape Town South Africa School of Dentistry and Oral Health Griffith University Gold Coast Australia School of Material Science and Engineering East China University of Science and Technology Shanghai China

The human inflammatory periodontal diseases are amongst the most common of chronic diseases to affect adults. Periodontitis is regarded as “an inflammatory lesion, mediated by complex host-parasite interactions, that leads to the loss of connective tissue attachment to root surface cementum and adjacent alveolar bone”. Substantial data are available in the literature on the role of reactive oxygen species (ROS) and antioxidants in disorders such as the inflammatory diseases. However, remarkably little information is available on the periodontal diseases, which show many of the pathological features of other chronic inflammatory diseases. The periodontal tissues also provide an ideal medium within which to study mechanisms of ROS mediated tissue damage and of antioxidant defense in response to bacterial colonisation, through the non-invasive collection of GCF. The objectives of this study are to evaluate the novel chitosan based functional drug delivery systems which can be successfully incorporated into “dual action bioactive restorative materials” containing common antibiotics such as tetracycline, krill oil, aloe and aspirin as commonly used antioxidant species. Methods: The novel hydrogels will be investigated with respect to the antioxidant capacity and drug release capacity of the tetracycline from the designer drug delivery system, the use of SEM imaging for the characterization of the surfaces and reactive features of novel materials with antimicrobial potential. Results: A steady slow release of tetracycline, while maintaining antibiotic effects against the tested bacteria, for at least 10 days was shown from designer chitosan-antioxidant hydrogels. Within the limitations of the study design chitosan-antioxidant hydrogels are suitable materials for functional restorative and periodontal applications in vitro. The addition of antioxidants to the tetracycline containing prototype delivery system had a beneficial effect on the design of the hydrogel by slowing

关键词： Chitosan Hydrogels Tetracycline Reactive Oxygen Species Antioxidants Functional Biomaterials

Insights into chitosan hydrogels on dentine bond strength and cytotoxicity

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Open Journal of Stomatology 2013年第1期3卷 75-82页

作者： V. Tamara Perchyonok Sias Grobler shengmiao zhang Annette Olivier Theunis Oberholzer Oral and Dental Research Institute Faculty of Dentistry University of the Western Cape Cape Town South Africa School of Dentistry and Oral Health Griffith University Gold Coast Australia School of Material Science and Engineering East China University of Science and Technology Shanghai China VTPChem PTY Ltd. Melbourne Australia

Contemporary dental adhesives show favorable immediate results in terms of bonding effectiveness. However, the durability of resin-dentin bonds is their major problem. Materials and Methods: Preparation of 3 chitosan-antioxidant hydrogels was achieved using modified hydrogel preparation method. Their effect on the bond strength to dentine both short term (after 24 hours) and long term (after 6 months) were evaluated using shear bond strength measurements using Instron Universal Testing Mascine). The SEM was used to study the surface of the hydrogels. The cell survival rate (cytotoxicity) of the antioxidants resveratrol, β-carotene and propolis towards Balb/c 3T3 mouse fibroblast cells was also assessed using the standard MTT assay. Results: It was found that chitosan-H treated dentine gives significantly (p β-carotene (92%) > propolis (68%) > resveratrol (33%). Conclusion: the antioxidant-chitosan hydrogels significantly improved bonding to dentine with or without phosphoric acid treatment. The pH of the growth medium had a high influence on the cell survival rate of Balb/c mouse 3T3 fibroblast cells. The release of the antioxidant β-carotene would not have an influence on the pulp cells. These materials might address the current perspectives for improving bond durability.

关键词： Antioxidant-Chitosan Hydrogels SEM Bond Strength Cytotoxicity Mouse 3T3 Fibroblast Fibroblast

Insights into chitosan based gels as functional restorative biomaterials prototypes: <i>In vitro</i>approach

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Open Journal of Stomatology 2013年第9期3卷 22-30页

作者： Victoria Tamara Perchyonok shengmiao zhang Nicolaas J. Basson Sias Grobler Theunis Oberholzer Ward Massey Oral and Dental Research Institute Faculty of Dentistry University of the Western Cape Cape Town South Africa School of Dentistry and Oral Health Griffith University Gold Coast Australia School of Material Science and Engineering East China University of Science and Technology Shanghai China

Restorative materials in the new era aim to be “bioactive” and long-lasting. The purpose of the study was to design and evaluate novel chitosan hydrogels containing melatonin and/or propolis (antioxidant containing material), nystatin (antifungal), naproxen (pain relieve medication) and combinations thereof (chitosan-H-melatonin, chitosan-H-melatonin-naproxen, chitosan-H-propolis, chitosan-H-propolisnaproxen, chitosan-H-naproxen-propolis-melatonin, Chitosan/Propolis/Nystatin, Chitosan/Melatonin/Propolis/Nystatin, Chitosan/Propolis/BSA/Nystatin, Chitosan/Melatonin/BSA/Nystatin) as functional additive prototypes for further development of “dual function restorative materials”, to determine their effect on the dentin bond strength of a composite, to evaluate stability of the encapsulated antioxidants as well as evaluate antimicrobial properties of the selected group of “designer” functional materials. Materials and Methods: The above mentioned hydrogels were prepared by dispersion of the corresponding component in glycerol and acetic acid with the addition of chitosan gelling agent. The surface morphology (SEM), drug-polymer solid state interaction (FT-IR spectroscopy), released behaviours (physiological pH and also in acidic conditions), stability of the therapeutic agent-antioxidant-chitosan and the effect of the hydrogels on the shear bond strength of dentin were also evaluated. Results: The release of naproxen confers the added benefit of synergistic action of a functional therapeutic delivery when comparing the newly designed chitosan-based hydrogel restorative materials to the commercially available products alone. Neither the release of naproxen or the antioxidant stability was affected by storage over a 6-month period. The hydrogel formulations have a uniform distribution of drug content, homogenous texture and yellow colour (SEM study). All chitosan dentin treated hydrogels gave significantly

关键词： Therapeutic Polymers Adhesives Chitosan Hydrogels Propolis Melatonin Naproxen Antimicrobial Dentin Bonding Antioxidants Bioactive

N-doped graphene quantum dot-decorated N-TiO2/P-doped porous hollow g-C_(3)N_(4) nanotube composite photocatalysts for antibiotic photodegradation and H2 production

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 165-178页

作者： Jingshu Yuan Yao zhang Xiaoyan zhang Junjie zhang Shen’gen zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Xi’an Fanyi University Xi’an 710105China Shunde Graduate School of University of Science and Technology Beijing Foshan 528399China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao SAR 820000China

Exclusive responsiveness to ultraviolet light (~3.2 eV) and high photogenerated charge recombination rate are the two primary drawbacks of pure TiO_(2). We combined N-doped graphene quantum dots (N-GQDs), morphology regulation, and heterojunction construction strategies to synthesize N-GQD/N-doped TiO_(2)/P-doped porous hollow g-C_(3)N_(4) nanotube (PCN) composite photocatalysts (denoted as G-TPCN). The optimal sample (G-TPCN doped with 0.1wt% N-GQD, denoted as 0.1% G-TPCN) exhibits significantly enhanced photoabsorption, which is attributed to the change in bandgap caused by elemental doping (P and N), the improved light-harvesting resulting from the tube structure, and the upconversion effect of N-GQDs. In addition, the internal charge separation and transfer capability of0.1% G-TPCN are dramatically boosted, and its carrier concentration is 3.7, 2.3, and 1.9 times that of N-TiO_(2), PCN, and N-TiO_(2)/PCN(TPCN-1), respectively. This phenomenon is attributed to the formation of Z-scheme heterojunction between N-TiO_(2) and PCNs, the excellent electron conduction ability of N-GQDs, and the short transfer distance caused by the porous nanotube structure. Compared with those of N-TiO_(2), PCNs, and TPCN-1, the H2 production activity of 0.1%G-TPCN under visible light is enhanced by 12.4, 2.3, and 1.4times, respectively, and its ciprofloxacin (CIP) degradation rate is increased by 7.9, 5.7, and 2.9 times, respectively. The optimized performance benefits from excellent photoresponsiveness and improved carrier separation and migration efficiencies. Finally, the photocatalytic mechanism of 0.1% G-TPCN and five possible degradation pathways of CIP are proposed. This study clarifies the mechanism of multiple modification strategies to synergistically improve the photocatalytic performance of 0.1% G-TPCN and provides a potential strategy for rationally designing novel photocatalysts for environmental remediation and solar energy conversion.

关键词： N-doped TiO_(2) N-doped graphene quantum dots P-doped g-C_(3)N_(4) porous hollow nanotube heterojunction photocatalysis

Bioinspired-Interpenetrating Network (IPNs) Hydrogel (BIOF-INPs) and TMD <i>in Vitro</i>: Bioadhesion, Drug Release and Build in Free Radical Detection and Defense

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Open Journal of Stomatology 2015年第3期5卷 53-61页

作者： Victoria Tamara Perchyonok Vanessa Reher Nicolaas J. Basson shengmiao zhang Sias R. Grobler VTPCHEM PTY LTD Gold Coast Australia School of Dentistry and Oral Health Griffith University Gold Coast Australia Oral and Dental Research Institute Faculty of Dentistry University of the Western Cape Cape Town South Africa School of Material Science and Engineering East China University of Science and Technology Shanghai China

In this work, Bioactive-functionalized interpenetrating network (IPNs) hydrogel (BIOF-INPs) were prepared and investigated in vitro for the free radical detection/defense, therapeutic release as well as shear bond strength to dentine, ability to re-mineralize surface of the dentin after application of these bio-inspired materials using a biologically inspired mineralization process in vitro as well as investigating antimicrobial properties of the BIOF-INPs against S. aureous. The aim of this investigation was to evaluate the suitability and flexibility of the designer materials to act as an “in vitro” probe to gain insights into molecular origin of TMD and associated disorders.

关键词： TMD Functionalized IPNs Bio-Adhesion Drug Release Build in Free Radical Detection and Defense

Reversing free-electron transfer of sulfide cocatalyst for exceptional photocatalytic H_(2)evolution

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Journal of Materials Science & Technology 2024年第4期171卷 147-149页

作者： Yanfeng zhang Zhenyi zhang National Experimental Chemistry Teaching Center Hebei Key Laboratory of Inorganic Nano-materialsCollege of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Recently,Yu and co-workers deeply explore the potential impact of free electron transfer between co-catalysts and photocatalyst carriers on H_(2)evolution efficiency of active sites over MoS_(2+x).They pro-pose an electron-reversal tactics to evade the unexpected electron transfer and synchronously regulate the above transfer in a beneficial orientation for weakening hydrogen adsorption on S ***,this highlight not only discusses and summarizes the essences of electron reversal and the optimized H ad-sorption/desorption mechanism,but also emphasizes the significance of femtosecond transient absorp-tion spectroscopy(fs-TAS)and in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)for revealing charge transfer dynamics and *** anticipate that this highlight can disseminate a new per-spective on the roles of photocatalyst carriers in improving cocatalytic H_(2)-production kinetics.

关键词： Photocatalysis Cocatalyst Electron reversal Antibonding-orbital occupancy S–H bonds