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Imaging with a metamaterial ＂Im-Perfect＂ lens

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中国光学与应用光学 2010年第1期3卷 45-51页

作者： J. O. Shenk M. A. Fiddy w. yang Center for Optoelectronics and Optical Communications University of North Carolina at Charlotte Charlotte NC 28223 USA Department of Engineering and Technology Western Carolina University CuUowheeN. C. 28779 USA

There is widespread and strong interest in trying to fabricate a metamaterial in which both the permittivity and permeability are equal to -1 in order to achieve sub-wavelength imaging. Several metamaterial constructs have been proposed with varying degrees of success because of inherent losses, limited bandwidth and scattering from the abstracted circuit elements constituting the artificial material itself. A further limitation is the need to capture evanescent components from the object to be imaged that requires the lens to be located near the object. we have studied the underlying models and constraints that influence the design of a negative index lens and present this analysis as well as reviewing the opportunities. There are inevitable and well-known trade-offs between lens thickness, wavelength, dispersion and absorption. However, these can be characterized both numerically and experimentally, suggesting that a computational imaging approach to the recovery of sub-wavelength features might be effective. Depending on the specific details of the metamaterial employed for imaging, one can consider the data acquired to represent a set of coded apertures.

关键词：介电常数渗透性人造材料散射度

High-temperature-tolerant flexible supercapacitors: Gel polymer electrolytes and electrode materials

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Journal of Energy Chemistry 2025年第1期100卷 426-457页

作者： Chong Peng Xinyi Huang Mingwei Zhao Shuling Liao Quanhong yang Nianjun yang Siyu Yu School of Chemistry & Chemical Engineering Southwest University Nanoyang Group Tianjin Key Laboratory of Advanced Carbon and Electrochemical Energy Storage School of Chemical Engineering and Technology and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin University Department of Chemistry & IMO-IMOMEC Hasselt University

The development of flexible supercapacitors(FSCs) capable of operating at high temperatures is crucial for expanding the application areas and operating conditions of supercapacitors. Gel polymer electrolytes and electrode materials stand as two key components that significantly impact the efficacy of hightemperature-tolerant FSCs(HT-FSCs). They should not only exhibit high electrochemical performance and excellent flexibility, but also withstand intense thermal stress. Considerable efforts have been devoted to enhancing their thermal stability while maintaining high electrochemical and mechanical performance. In this review, the fundamentals of HT-FSCs are outlined. A comprehensive overview of state-of-the-art progress and achievements in HT-FSCs, with a focus on thermally stable gel polymer electrolytes and electrode materials is provided. Finally, challenges and future perspectives regarding HT-FSCs are discussed, alongside strategies for elevating operational temperatures and *** review offers both theoretical foundations and practical guidelines for designing and manufacturing HT-FSCs, further promoting their widespread adoption across diverse fields.

关键词： Polymer membrane electrodes

Loss of the Krüppel-like factor 4 tumor suppressor is associated with epithelial-mesenchymal transition in colorectal cancer

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Journal of Cancer Metastasis and Treatment 2019年第11期4卷 47-57页

作者： Kimberley C.Agbo Jessie Z.Huang Amr M.Ghaleb Jennie L.williams Kenneth R.Shroyer Agnieszka B.Bialkowska Vincent w.yang Department of Medicine Stony Brook University School of MedicineStony BrookNY 11794USA Department of Pathology Stony Brook University School of MedicineStony BrookNY 11794USA Department of Family Population and Preventive MedicineStony BrookNY 11794USA Department of Physiology and Biophysics Stony Brook University School of MedicineStony BrookNY 11794USA

Aim: Colorectal cancer (CRC) is the third leading cancer-related cause of death due to its propensity to metastasize. Epithelial-mesenchymal transition (EMT) is a multistep process important for invasion and metastasis of CRC. Krüppel-like factor 4 (KLF4) is a zinc finger transcription factor highly expressed in differentiated cells of the intestinal epithelium. KLF4 has been shown to play a tumor suppressor role during CRC tumorigenesis - its loss accelerates development and progression of cancer. The present study examined the relationship between KLF4 and markers of EMT in CRC. Methods: Immunofluorescence staining for KLF4 and EMT markers was performed on archived patient samples after colorectal cancer resection and on colonic tissues of mice with colitis-associated cancer. Results: we found that KLF4 expression is lost in tumor sections obtained from CRC patients and in those of mouse colon following azoxymethane and dextran sodium sulfate (AOM/DSS) treatment when compared to their respective normal appearing mucosa. Importantly, in CRC patient tumor sections, we observed a negative correlation between KLF4 levels and mesenchymal markers including TwIST, β-catenin, claudin-1, N-cadherin, and ;vimentin. Similarly, in tumor tissues from AOM/DSS-treated mice, KLF4 levels were negatively correlated with mesenchymal markers including SNAI2, β-catenin, and vimentin and positively correlated with the epithelial marker E-cadherin. Conclusion: These findings suggest that the loss of KLF4 expression is a potentially significant indicator of EMT in CRC.

关键词： Krüppel-like factor 4 colorectal cancer epithelial-mesenchymal transition

Adaptive spraying decision system for plant protection unmanned aerial vehicle based on reinforcement learning

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International Journal of Agricultural and Biological Engineering 2022年第4期15卷 16-26页

作者： Ziyuan Hao Xinze Li Chao Meng wei yang Minzan Li Key Laboratory of Smart Agriculture System Integration Ministry of EducationChina Agricultural UniversityBeijing 100083China Key Laboratory of Agricultural Information Acquisition Technology Ministry of Agriculture and Rural AffairsChina Agricultural UniversityBeijing 100083China

To solve the problem of lacking scientific guidance in aerial pesticide application,this study introduced an adaptive spraying decision system(ASDS)for Unmanned Aerial Vehicle(UAV)spraying to guide the operators of plant protection UAVs to set reasonable spraying parameters under complicated *** minimum applied volume rate,proper spraying velocity,spraying height,and initial droplet size were recommended by the *** key factor of the decision system is the decision model of reinforcement learning based on the actor-critic neural *** specific,the field experimental data were used to train the critic and actor networks,which made the model adaptive to optimize the output of spraying *** with the conventional spraying parameters,the spraying parameters recommended by the ASDS had a positive impact on wheat *** decision results of the ASDS showed that the spraying volume rate was lower in the blocks with a small leaf area *** addition,the spraying volume rate for the whole parcel was reduced by 14%.After UAV spraying,the uniformity of the droplet deposition in the ASDS parcel was better than that in the conventional ***,the penetrability of the droplets and the control efficacy for the brown wheat mite Petrobia latens(Muller)were similar in the two *** ASDS can recommend the optimal spraying parameters to minimize pesticide application.

关键词： unmanned aerial vehicle spraying parameters decision reinforcement learning droplet deposition

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牙组织工程的研究现状和展望

中国组织工程研究与临床康复 2007年第10期11卷 1915-1917,1922页

作者：杨薇李曦光辽宁医学院口腔系辽宁省锦州市121000

目的:综合分析牙组织工程的研究现状及发展方向。资料来源:应用计算机检索Pubmed数据库1994-01/2006-10有关牙组织工程的文章,检索词“teeth tissue engineering”,限定文章语言种类为English。同时计算机检索中国期刊全文数据库1994-01... 详细信息

目的:综合分析牙组织工程的研究现状及发展方向。资料来源:应用计算机检索Pubmed数据库1994-01/2006-10有关牙组织工程的文章,检索词“teeth tissue engineering”,限定文章语言种类为English。同时计算机检索中国期刊全文数据库1994-01/2006-10期间的相关文章,检索词“牙组织工程”,限定文章语言种类为中文。资料选择:对资料进行初审,选取符合研究要求的有关文章找全文。纳入标准:文章所述内容应与牙组织工程的研究相关。排除标准:重复性研究。资料提炼:共收集到110篇有关牙组织工程的文章,选取其中有代表性的31篇进行综述。资料综合:牙组织工程的研究是近年来最为活跃的口腔医学研究领域之一,如何利用人工方法设计和制造出具有生物学活性的牙齿,是国内外学者所追求的目标和着力研究的热点课题,并期待着在不久的将来将再生牙齿应用于临床。①从牙组织工程中获取具有较强生长和分化能力的种子细胞、优选较为适宜的三维支架材料以及用以促进牙齿再生的生长因子3方面内容进行具体阐述国内外的研究现状。②对于牙齿形成干细胞分化调控机制已有一定的了解,但是牙发生的分子生物学机制尚未完全清楚,对牙发生发育的众多机制的正确认识将对于牙组织工程的研究进展起到决定性作用,这也将是研究者面对的一大挑战。结论:牙组织工程研究中获取来源容易且具有成牙能力的种子细胞;在成体环境中产生牙根且通过牙周膜与颌骨相连接;牙齿的大小和形态必须可以控制,这些技术均已有较好的研究结果,因此,在不远的时间内,利用生物手段实现牙齿再生很快将变为现实。

关键词：组织工程牙综述文献

Preparation of Low Ratio Magnesium Ccement by Acid Leaching Treatment of Boron Mud

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Journal of wuhan University of Technology(Materials Science) 2025年第1期40卷 120-129页

作者： yang Mei ZHANG Mingzhe CHEN Hao School of Materials Science and Engineering Shenyang Jianzhu UniversityShenyang 110168China School of Physical Science and Technology Shenyang Normal UniversityShenyang 110168China

The effects of liquid-solid ratio and reaction time on the leaching rate of magnesium at room temperature were investigated,as well as the effects of the molar ratio of MgO/MgCl_(2),the amount of water added,and the amount of acid-impregnated slag dosed on the compressive strength and water resistance of *** results showed that the magnesium element in the boron mud could be maximally leached under the conditions of 1:1 concentration of hydrochloric acid at room temperature,liquid-solid ratio of 2.5 mL·g^(-1),and reaction time of 5 h,and the main products were amorphous SiO_(2) as well as a small amount of magnesium olivine which had not been completely *** LR-MOC prepared using the acid-soaked mixture could reach a softening coefficient of 0.85 for 28 d of water immersion when the molar ratio of MgO/MgCl_(2) was 2.2,the amount of water added was 0 g,and the acid-soaked slag dosing was 40 wt%,which also led to an appreciable late-strength,with an increase of 19.4%in compressive strength at 28 d compared to that at 7 *** previous studies,LR-MOC prepared in this way has a final strength phase that is not the more easily hydrolysed 3-phase but the lath-like *** this phenomenon,we analyzed the mechanism and found that,during the acid leaching process,a part of amorphous SiO_(2) dissolved in the acid leaching solution formed a silica sol,in which Mg^(2+)played a bridging role to make the silica sol more *** the addition and hydrolysis of MgO,the silica sol gel coagulation slows down,providing a capping layer to inhibit the hydrolysis of the 5-phase crystals and providing some strength after *** amorphous SiO_(2) in the other part of the acid-impregnated slag generated M-S-H gel with Mg^(2+)and OH-,which synergised with the dense structure composed of interlocking crystals to improve the water resistance of LR-MOC.

关键词： boron mud magnesium chloride-oxygen cement acid immersion water resistance silica sol

A surface engineering strategy for the stabilization of zinc metal anodes with montmorillonite layers toward long-life rechargeable aqueous zinc ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 94-105页

作者： wenbo wang Ruifeng Xu Xu Zhang Peiyu wang Bao yang Bingjun yang Juan yang Kailimai Su Pengjun Ma Yanan Deng Xianfeng Fan wanjun Chen Key Laboratory for Electronic Materials College of Electrical Engineering Northwest Minzu University Resource Chemistry and Energy Materials Research Center State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Institute for Materials and Processes School of Engineering University of Edinburgh

Rechargeable aqueous zinc-ion batteries （AZIBs） exhibit appreciable potential in the domain of electrochemical energy ***,there are serious challenges for AZIBs,for instance zinc dendrite growth,hydrogen evolution reaction （HER）,and corrosion side ***,we propose a surface engineering modification strategy for coating the montmorillonite （MMT） layer onto the surface of the Zn anode to tackle these issues,thereby achieving high cycling stability for rechargeable *** results reveal that the MMT layer on the surface of the Zn anode is able to provide ordered zincophilic channels for zinc ions migration,facilitating the reaction kinetics of zinc *** functional theory（DFT） calculations and water contact angle （CA） tests prove that MMT@Zn anode exhibits superior adsorption capacity for Zn2+and better hydrophobicity than the bare Zn anode,thereby achieving excellent cycling ***,the MMT@Zn||MMT@Zn symmetric cell holds the stable cycling over 5600 h at 0.5 mA cm-2and 0.125 m A h cm-2,even exceeding 1800 h long cycling under harsh conditions of 5 m A cm-2and 1.25 m A h *** MMT@Zn||V2O5full cell reaches over 3000 cycles at 2 A g-1with excellent rate ***,this surface engineering modification strategy for enhancing the electrochemical performance of AZIBs represents a promising application.

关键词： Hydrogen evolution reaction

从一个医保组织的案例看发现信息质量问题的根本原因

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中国科技资源导刊 2009年第2期41卷 13-19页

作者： yang w.Lee 苏颖美国东北大学信息运筹与分析系商学院马萨诸塞州波士顿02114 中国科学技术信息研究所北京100038

文章通过一个详细的案例研究,描述一个医保组织使用假设测试和验证方法发现信息质量问题的过程。这种方法沿用传统的科学观察方法,提出一个假设,并对其进行测试,验证这一假设是合理的。文章认为,尽管这一案例代表一个企业的经验,但仍可... 详细信息

文章通过一个详细的案例研究,描述一个医保组织使用假设测试和验证方法发现信息质量问题的过程。这种方法沿用传统的科学观察方法,提出一个假设,并对其进行测试,验证这一假设是合理的。文章认为,尽管这一案例代表一个企业的经验,但仍可以作为解决取得高质量信息的问题和复杂性的综合实例。

关键词：信息质量医疗保险数据质量案例

The gating machanism of TRPM2 by ADP ribose and calcium

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The gating machanism of TRPM2 by ADP ribose and calcium