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基于光束偏移器的光的轨道角动量分束器

物理学报 2024年第7期73卷 163-170页

作者：张卓张景风孔令军北京理工大学物理学院先进光电量子结构设计与测量教育部重点实验室纳米光子学与超精密光电系统北京市重点实验室北京100081

近年来,光的轨道角动量自由度的高维度特性引起了广泛的关注.该自由度在许多科学领域得到了研究和应用,特别是在光通讯和量子信息领域.为了充分利用轨道角动量的高维特性,不同的轨道角动量态的非破坏分离成为一个最基本的要求.然而,目... 详细信息

近年来,光的轨道角动量自由度的高维度特性引起了广泛的关注.该自由度在许多科学领域得到了研究和应用,特别是在光通讯和量子信息领域.为了充分利用轨道角动量的高维特性,不同的轨道角动量态的非破坏分离成为一个最基本的要求.然而,目前已有的轨道角动量分束系统,要么在稳定性和级联拓展性方面有所不足;要么分离后的轨道角动量态的特性遭到严重破坏,无法参与进一步的相互作用过程.本文基于光束偏移器构建微型Mach-Zehnder干涉仪,设计了一个稳定且紧凑的轨道角动量分束器,实现了轨道角动量模式的非破坏分束.设计中由于只存在光束的全反射,因此理论上能量损耗为零.在微型Mach-Zehnder干涉仪中的光束经过的光学元件相同,且光束的空间偏移量较小,所以该轨道角动量分束器具有很好的稳定性.此外,由于被分开的轨道角动量态与入射的轨道角动量态具有相同的传播方向,因此该分束器具有很好的可拓展性,便于级联使用.本研究对轨道角动量这一高维自由度在光通讯等相关领域的应用有重要意义.

关键词：轨道角动量态识别光通讯

Improvement for creep strength of a second-generation single crystal superalloy by design of heat treatments

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Rare Metals 2024年第1期43卷 342-350页

作者： Wan-Shun Xia xin-Bao Zhao Jia-Chen Xu Quan-Zhao Yue Qing-Qing Ding Huan-Chang Duan Yue-feng Gu Hong-Bin Bei Ze Zhang Institute of Superalloys Science and Technology School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Silicon and Advanced Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

Design of heat treatments is related to the key technology for development of nickel-based single crystal superalloys(Ni-SXs). Based on the full understanding of the solidification characteristics, this work applies optimization design of heat treatments for a second-generation Ni-SX. Microstructure evolution and creep properties are compared in the material under conventional/standard(Std.) and optimized(Opt.) treatments. For the Std. sample,strong dendritic segregations determine inconsistent microstructure evolution in the dendritic(D) and interdendritic region(ID), while the latter serves as weak area to have the prior microcrack initiation, damaging overall performance of the alloy. The Opt. treatment applies higher homogenization temperature, leading to overall reduced segregations, while not inducing incipient melting. A lower temperature of first-step ageing is used to lower the size ofγ'particles. These help to form the more uniform microstructure in dendritic and interdendritic region and relieve the inconsistent microstructure evolution. The balanced local strength makes ID no longer as the weak area,thus restricting microcrack initiation. Great improvement of high temperature and low stress property is obtained by this progress, leading to the pronounced increase of creep rupture life under 1100 °C/140 MPa.

关键词： Single crystal superalloy Heat treatment Segregation Solidification Creep property

Electrically tunable phase-change metasurface for dynamic infrared thermal camouflage

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Photonics Research 2024年第2期12卷 292-300页

作者： YUfeng XIONG YUNZHENG WANG CHAO feng YAOLAN TIAN LIANG GAO JUN-LEI WANG ZHUANG zhuo XIAN ZHAO Center for Optics Research and Engineering Key Laboratory of Laser&Infrared SystemMinistry of EducationShandong UniversityQingdao 266237China School of Information Science and Engineering Shandong UniversityQingdao 266237China

Dynamic infrared thermal camouflage technology has attracted extensive attention due to its ability to thermally conceal targets in various environmental backgrounds by tuning thermal *** use of phase change materials(PCMs)offers numerous advantages,including zero static power,rapid modulation rate,and large emissivity tuning ***,existing PCM solutions still encounter several practical application challenges,such as temperature uniformity,amorphization achievement,and adaptability to different *** this paper,we present the design of an electrically controlled metal-insulator-metal thermal emitter based on a PCM metasurface,and numerically investigate its emissivity tunability,physical mechanisms,heat conduction,and thermal camouflage performance across different ***,the influence of the quench rate on amorphization was studied to provide a guidance for evaluating and optimizing device *** results reveal that the thermal emitter exhibits a wide spectral emissivity tuning range between 8 and 14μm,considerable quench rates for achieving amorphization,and the ability to provide thermal camouflage across a wide background temperature ***,it is anticipated that this contribution will promote the development of PCM-based thermal emitters for practical dynamic infrared thermal camouflage technology with broad applications in both civilian and military domains.

关键词： thermal dynamic phase

A novel Ce_(0.485)Zr_(0.485)Y_(0.03)O_(2) composite oxide with surface doping of Y and its application in Pd-only three-way catalyst

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Rare Metals 2024年第2期43卷 749-757页

作者： Zheng Zhao Wei-xin Zhao Yong-Qi Zhang Mei-Sheng Cui Yong-Ke Hou Dong-Ming Chen Juan-Yu Yang Zong-Yu feng Xiao-Wei Huang National Engineering Research Center for Rare Earth Grirem Advanced Materials Co.Ltd.GRINM Group Corporation LimitedBeijing100088China Griem Hi-Tech Co.Ltd. Langfang065000China Rare Earth Functional Materials(Xiong’an)Innovation Venter Co.Ltd. Baoding071700China

The ceria-zirconia compound oxide-supported noble metal Pd(Pd@CZ)is widely used in three-way ***,the surface structure of CZ plays an important role in catalytic activity of ***,how to regulate the surface structure of CZ and clarify the structure–activity relationship is still a *** this paper,a strategy is proposed to develop high activity Pd@CZ nanocatalysts by tuning Y doping sites in *** precipitate-deposition method is developed to prepare the novel Ce_(0.485)Zr_(0.485)Y_(0.03)O_(2) composite with surface doping of Y(CZ-Y-S).In addition,the Pd@CZ-Y-S(Pd supported on CZ-Y-S)exhibits superior catalytic activity for HC,CO,and NO oxide,wherein,for CO and C_(3)H_(6) oxidation,the low-temperature activity of Pd@CZ-Y-S is still 20%higher than that of Pd@CZ-Y-B(Y bulk doping)and commercial Pd@CZ after 1000℃/4 h *** effect mechanism is further studied by density functional theory(DFT)*** with Pd@CZ-Y-B,Pd@CZ-Y-S shows the lower CO oxide reaction energy barriers due to the weaker adsorption strength of *** Y surface doping strategy could provide valuable insights for the development of highly efficient Pd@CZ catalyst with extensive applications.

关键词： Rare earth Ceria-zirconia-supported Pd Surface doping Experiment and theory Catalytic application

In situ tracking of the lithiation and sodiation process of disodium terephthalate as anodes for rechargeable batteries by Raman spectroscopy

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Nano Research 2024年第1期17卷 245-252页

作者： Xiu-Mei Lin Chong Han xin-Tao Yang Jia-Sheng Lin Wei-Qiang Yang Hong-Xu Guo Yao-Hui Wang Jin-Chao Dong Jian-feng Li Department of Chemistry and Environment Science Fujian Province University Key Laboratory of Analytical ScienceMinnan Normal UniversityZhangzhou 363000China College of Energy College of Chemistry and Chemical EngineeringCollege of MaterialsState Key Laboratory of Physical Chemistry of Solid SurfacesiChEMXiamen UniversityXiamen 361005China Institute of Optical and Electronic Technology China Jiliang UniversityHangzhou 310018China

Organic compounds represent an appealing group of electrode materials for rechargeable batteries due to their merits of biomass,sustainability,environmental friendliness,and *** terephthalate(Na_(2)C_(8)H_(4)O_(4),Na_(2)TP),an organic salt with a theoretical capacity of 255 mAh·g^(-1),is electroactive towards both lithium and ***,its electrochemical energy storage(EES)process has not been directly observed via in situ characterization techniques and the underlying mechanisms are still under ***,in situ Raman spectroscopy was employed to track the de/lithiation and de/sodiation processes of *** appearance and then disappearance of the–COOLi Raman band at 1625 cm^(-1) during the de/lithiation,and the increase and then decrease of the–COONa Raman band at 1615 cm^(-1) during the de/sodiation processes of Na2TP elucidate the one-step with the 2Li+or 2Na+transfer *** also found that the inferior cycling stability of Na2TP as an anode for sodium-ion batteries(SIBs)than lithium-ion batteries(LIBs)could be due to the larger ion radium of Na+than Li+,which results in larger steric resistance and polarization during *** Na2TP,therefore,shows greater changes in spectra during de/sodiation than de/*** expect that our findings could provide a reference for the rational design of organic compounds for EES.

关键词： disodium terephthalate(Na_(2)C_(8)H_(4)O_(4) Na2TP) in situ Raman spectroscopy de/lithiation de/sodiation mechanisms

Success of susceptibility-guided eradication of Helicobacter pylori in a region with high secondary clarithromycin and levofloxacin resistance rates

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World Journal of Gastroenterology 2024年第2期30卷 184-195页

作者： Yan-Meng Wang Mo-Ye Chen Jing Chen xin-He Zhang Yan feng Yu-Xi Han Yi-Ling Li Department of Gastroenterology The First Affiliated Hospital of China Medical UniversityShenyang 110000Liaoning ProvinceChina Key Laboratory of Cancer Etiology and Prevention in Liaoning Education Department The First Hospital of China Medical UniversityShenyang 110000Liaoning ProvinceChina

BACKGROUND Resistance to clarithromycin(CLA)and levofloxacin(LFX)of Helicobacter pylori(***)is increasing in severity,and successful eradication is ***,the eradication success rate has greatly declined,leaving a large number of patients with previous treatment *** To investigate secondary resistance rates,explore risk factors for antibiotic resistance,and assess the efficacy of susceptibility-guided *** We recruited 154 subjects positive for Urea Breath Test who attended The First Affiliated Hospital of China Medical University between July 2022 and April *** underwent a string test after an overnight *** gastric juice was obtained and transferred to vials containing storage ***,DNA extraction and the specific DNA amplification were performed using quantitative polymerase chain reaction(qPCR).Demographic information was also analyzed as part of the *** on these results,the participants were administered susceptibility-guided *** was compared with that of the empiric treatment *** A total of 132 individuals tested positive for the *** ureA gene by qPCR *** resistance rate reached a high level of 82.6%(n=109),LFX resistance rate was 69.7%(n=92)and dual resistance was 62.1%(n=82).Gastric symptoms[odds ratio(OR)=2.782;95%confidence interval(95%CI):1.076-7.194;P=0.035]and rural residence(OR=5.152;95%CI:1.407-18.861;P=0.013)were independent risk factors for secondary resistance to CLA and LFX,respectively.A total of 102 and 100 individuals received susceptibility-guided therapies and empiric treatment,*** antibiotic susceptibility-guided treatment and empiric treatment groups achieved successful eradication rates of 75.5%(77/102)and 59.0%(59/411)by the intention-to-treat(ITT)analysis and 90.6%(77/85)and 70.2%(59/84)by the per-protocol(PP)analysis,*** eradication rates of these two treatment strategies were significantly

关键词： Helicobacter pylori Antibiotic resistance Clarithromycin Levofloxacin String-test Susceptibility-guided therapy Eradication rate

Emerging role of exosomes in ulcerative colitis: Targeting NOD-like receptor family pyrin domain containing 3 inflammasome

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World Journal of Gastroenterology 2024年第6期30卷 527-541页

作者： xin Li Li-Jiang Ji Kai-Di feng Hua Huang Mei-Rou Liang Shi-Jin Cheng Xiu-Dong Meng School of Basic Medicine Guizhou University of Traditional Chinese MedicineGuiyang 550025Guizhou ProvinceChina Department of Anorectal Surgery Changshu Hospital Affiliated to Nanjing University of Chinese MedicineChangshu 215500Jiangsu ProvinceChina College of Traditional Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China

Ulcerative colitis(UC)is a chronic recurrent inflammatory bowel *** ongoing advances in our understanding of UC,its pathogenesis is yet unelu-cidated,underscoring the urgent need for novel treatment strategies for patients with *** are nanoscale membrane particles that mediate intercellular communication by carrying various bioactive molecules,such as proteins,RNAs,DNA,and *** NOD-like receptor family pyrin domain containing 3(NLRP3)inflammasome is a cytosolic tripartite protein complex whose activation induces the maturation and secretion of proinflammatory cytokines interleukin-1β(IL-1β)and IL-18,triggering the inflammatory response to a pathogenic agent or *** evidence suggests that exosomes are new modulators of the NLRP3 inflammasome,with vital roles in the pathological process of ***,recent evidence is reviewed on the role of exosomes and NLRP3 inflammasome in ***,the dual role of exosomes on NLRP3 inflammasome and the effect of NLRP3 inflammasome on exosome secretion are ***,an outlook on the directions of exosome-NLRP3 inflammasome crosstalk research in the context of UC is proposed and areas of further research on this topic are high-lighted.

关键词： Ulcerative colitis Exosomes Inflammasome Evidence Therapeutics

苦参碱对人肺癌A549细胞增殖、侵袭和血管生成的抑制作用及其机制研究

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现代药物与临床 2017年第5期32卷 767-771页

作者：卓新凤姬颖华新乡市中医院药剂科河南新乡453000 新乡医学院第一附属医院肿瘤科河南新乡453000

目的探讨苦参碱对肺癌A549细胞增殖、侵袭和血管生成抑制作用以及其作用机制。方法不同浓度苦参碱组加入到A549人肺癌细胞株中,利用ELISA法研究了苦参碱对EGFR-TPK的抑制作用,利用MTT法测定苦参碱对A549细胞的抑制作用,Transwell法检测... 详细信息

目的探讨苦参碱对肺癌A549细胞增殖、侵袭和血管生成抑制作用以及其作用机制。方法不同浓度苦参碱组加入到A549人肺癌细胞株中,利用ELISA法研究了苦参碱对EGFR-TPK的抑制作用,利用MTT法测定苦参碱对A549细胞的抑制作用,Transwell法检测苦参碱对肺癌A549细胞侵袭的抑制作用,酶标仪法检测苦参碱对细胞凋亡蛋白caspase 3活性的影响,Western blotting法检测苦参碱存在下A549中VEGF、HIF-1α的表达。结果苦参碱对EGFR-TPK半数抑制率为11.26±1.02μmol/L,对肺癌A549细胞生长IC50为30.45±3.02μmol/L,都具有良好的抑制能力,但对于MRC-5细胞表现了较低的毒性;苦参碱与对照组相比能够诱导肿瘤细胞穿过人工基底膜的数量减少,差异有显著性(P<0.05);与对照组比较,苦参碱能显著提高A549中凋亡蛋白caspase 3活性(P<0.05);苦参碱能够下调HIF-1α和VEGF的表达。结论苦参碱可降低EGFR-TPK活性和HIF-1α、VEGF的表达,激活caspase 3活性,对肺癌肿瘤A549细细胞的侵袭、增殖和血管生成产生抑制作用。

关键词：苦参碱 A549细胞抑制作用血管生成 caspase 3活性 HIF-1α表达 VEGF表达

Differentiation and immunosuppressive function of CD19^(+)CD24^(hi)CD27^(+) regulatory B cells are regulated through the miR-29a-3p/NFAT5 pathway

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 472-480页

作者： Jin-Yang Li Tian-Shuo feng Ji Gao xin-Xiang Yang Xiang-Cheng Li Zhen-Hua Deng Yong-Xiang Xia Zheng-Shan Wu Hepatobiliary Center the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China Key Laboratory of Liver Transplantation Chinese Academy of Medical SciencesNanjing 210029China NHC Key Laboratory of Living Donor Liver Transplantation Nanjing Medical UniversityNanjing 210029China

Background: Regulatory B cells(Bregs) is an indispensable element in inducing immune tolerance after liver transplantation. As one of the microRNAs(miRNAs), mi R-29a-3p also inhibits translation by degrading the target mRNA, and yet the relationship between Bregs and mi R-29a-3p has not yet been fully explored. This study aimed to investigate the impact of miR-29a-3p on the regulation of differentiation and immunosuppressive functions of memory Bregs(m Bregs) and ultimately provide potentially effective therapies in inducing immune tolerance after liver transplantation. Methods: Flow cytometry was employed to determine the levels of Bregs in peripheral blood mononuclear cells. TaqMan low-density array miRNA assays were used to identify the expression of different miRNAs, electroporation transfection was used to induce mi R-29a-3p overexpression and knockdown, and dual luciferase reporter assay was used to verify the target gene of miR-29a-3p. Results: In patients experiencing acute rejection after liver transplantation, the proportions and immunosuppressive function of m Bregs in the circulating blood were significantly impaired. mi R-29a-3p was found to be a regulator of m Bregs differentiation. Inhibition of miR-29a-3p, which targeted nuclear factor of activated T cells 5(NFAT5), resulted in a conspicuous boost in the differentiation and immunosuppressive function of m Bregs. The inhibition of mi R-29a-3p in CD19~+ B cells was capable of raising the expression levels of NFAT5, thereby promoting B cells to differentiate into m Bregs. In addition, the observed enhancement of differentiation and immunosuppressive function of m Bregs upon mi R-29a-3p inhibition was abolished by the knockdown of NFAT5 in B cells. Conclusions: mi R-29a-3p was found to be a crucial regulator for m Bregs differentiation and immunosuppressive function. Silencing mi R-29a-3p could be a potentially effective therapeutic strategy for inducing immune tolerance after liver transplantation.

关键词： Regulatory B cells miR-29a-3p NFAT5 Liver transplantation