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Near infrared emissions from both high efficient quantum cutting (173%) and nearly-pure-color upconversion in NaY(WO_(4))_(2):Er^(3+)/Yb^(3+) with thermal management capability for silicon-based solar cells

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Light(Science & Applications) 2024年第1期13卷 113-126页

作者： Duan Gao Baojiu Chen Xuezhu Sha Yuhang Zhang Xin Chen Li Wang Xizhen Zhang Jinsu Zhang Yongze Cao Yichao Wang Lei Li Xiangping Li Sai Xu Hongquan Yu lihong cheng School of Science Dalian Maritime UniversityDalian 116026 LiaoningChina

Raising photoelectric conversion efficiency and enhancing heat management are two critical concerns for siliconbased solar cells.In this work,efficient Yb^(3+) infrared emissions from both quantum cutting and upconversion were demonstrated by adjusting Er^(3+) and Yb^(3+) concentrations,and thermo-manage-applicable temperature sensing based on the luminescence intensity ratio of two super-low thermal quenching levels was discovered in an Er^(3+)/Yb^(3+) codoped tungstate system.The quantum cutting mechanism was clearly decrypted as a two-step energy transfer process from Er^(3+) to Yb^(3+).The two-step energy transfer efficiencies,the radiative and nonradiative transition rates of all interested 4 f levels of Er^(3+) in NaY(WO_(4))_(2) were confirmed in the framework of Föster-Dexter theory,Judd-Ofelt theory,and energy gap law,and based on these obtained efficiencies and rates the quantum cutting efficiency was furthermore determined to be as high as 173%in NaY(WO_(4))_(2):5 mol%Er^(3+)/50 mol%Yb^(3+) sample.Strong and nearly pure infrared upconversion emission of Yb3+under 1550 nm excitation was achieved in Er^(3+)/Yb^(3+)co-doped NaY(WO_(4))_(2) by adjusting Yb^(3+) doping concentrations.The Yb^(3+) induced infrared upconversion emission enhancement was attributed to the efficient energy transfer ^(4)I_(11/2)(Er^(3+))+^(2)F_(7/2)(Yb^(3+))→^(4)I_(15/2)(Er^(3+))+^(2)F_(5/2)(Yb^(3+))and large nonradiative relaxation rate of ^(4)I_(9/2).Analysis on the temperature sensing indicated that the NaY(WO_(4))_(2):Er^(3+)/Yb^(3+)serves well the solar cells as thermos-managing material.Moreover,it was confirmed that the fluorescence thermal quenching of ^(2)H_(11/2)/^(4)S_(3/2) was caused by the nonradiative relaxation of ^(4)S_(3/2).All the obtained results suggest that NaY(WO_(4))_(2):Er^(3+)/Yb^(3+) is an excellent material for silicon-based solar cells to improve photoelectric conversion efficiency and thermal management.

关键词： quantum thermal relaxation

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HPMA modified aluminium nitride powder for aqueous tape casting of AlN ceramic substrates

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Journal of Advanced Ceramics 2023年第9期12卷 1701-1711页

作者： Meng Li Jianping Ai Zhengjuan Wang Zhenhai Xue lihong cheng Guohong Zhou Shiwei Wang School of Materials and Mechatronics Jiangxi Science&Technology Normal UniversityNanchang 330038China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China

Aluminum nitride(AlN)is considered one of the most desirable materials for integrated circuits and electronic packaging substrates.However,raw AlN powder reacts easily with water,forming Al(OH)3 or AlOOH on the surface and hindering the development of an aqueous tape-casting process for preparing AlN ceramic substrates.In this study,hydrolyzed polymaleic anhydride(HPMA)was used to modify AlN powder,which has good water solubility and dispersibility.The AlN powder was modified with 5 wt%HPMA remained stable in water for at least 90 h under magnetic stirring condition and 24 h under ball milling condition,indicating that HPMA-modified AlN powder has good resistance to hydrolysis.The action mechanism of HPMA is revealed.Firstly,–COOH of the HPMA polymer and the oxide layer on the surface of the AlN powder underwent a dehydration condensation reaction to form a compound.Secondly,long chains of the polymer further coated the surface of the AlN powder,forming an anti-hydration layer with a thickness of about 7.0 nm on the surface of the AlN particles.In addition,AlN green sheets were successfully prepared by aqueous tape casting using the HPMA-modified AlN powder without additional dispersants.Subsequently,AlN ceramic substrates were obtained by sintering at 1750℃for 4 h under an N2 atmosphere with a pressure of 0.2 MPa.The relative density and thermal conductivity were tested to be 97.3%and 122 W/(m·K),respectively.

关键词： aluminum nitride(AlN) surface modification hydrolyzed polymaleic anhydride(HPMA) hydrolysis resistance aqueous tape casting

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Effects of Bi^(3+) on down-/up-conversion luminescence,temperature sensing and optical transition properties of Bi^(3+)/Er^(3+)co-doped YNbO_(4) phosphors

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Journal of Rare Earths 2022年第3期40卷 381-389,I0001页

作者： Xin Wang Xiangping Li Hongquan Yu Sai Xu Jiashi Sun lihong cheng Xizhen Zhang Jinsu Zhang Yongze Cao Baojiu Chen School of Science Dalian Maritime UniversityDalian 116026China

A series of YNbO_(4):Bi^(3+) and YNbO_(4):Bi^(3+)/Er^(3+) phosphors were prepared by a conventional high temperature solid-state reaction method.The results of XRD and Rietveld refinement confirm that monoclinic phase YNbO_(4)samples are achieved.The down-/up-conversion luminescence of Er^(3+) ions was investigated under the excitation of ultraviolet light(327 nm)and near infrared light(980 nm).Under 327 nm excitation,broad visible emission band from Bi^(3+) ions and characteristic green emission peaks from Er^(3+) ions are simultaneously observed,while only strong green emissions from Er^(3+) ions are detected upon excitation of 980 nm.Remarkable emission enhancement is observed in down-/up-conversion luminescence processes by introducing Bi^(3+) ions into Er^(3+)-doped YNbO_(4)phosphors.Pumped current versus up-conversion emission intensity study shows that two-photon processes are responsible for both the green and the red up-conversion emissions of Er^(3+)ion.Through the study of the temperature sensing property of Er^(3+) ion,it is affirmed that the temperature sensitivity is sensitive to the doping concentration of Bi^(3+) ions.By comparing the experimental values of the radiative transition rate ratio of the two green emission levels of Er^(3+) ions and the theoretical values calculated by Judd-Ofelt(J-O)theory,it is concluded that the temperature sensing property of Er^(3+) ions is greatly affected by the energy level splitting.

关键词： YNbO_(4):Bi^(3+)/Er^(3+) Down-conversion luminescence Up-conversion luminescence Temperature sensing Rare earths

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基于模糊控制的农产品冷冻库网络控制系统研究

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农机化研究 2024年第3期46卷 87-91页

作者：冯双林程丽红广西工业职业技术学院南宁530003

介绍了农产品冷冻库网络控制系统的结构及其特点,设计了基于模糊自适应整定的PID控制器,实现了对农产品冷冻库网络控制系统的控制。基于TrueTime仿真工具箱的仿真实验表明:设计的农产品冷冻库网络控制系统具有响应速度快、稳定性强和抗... 详细信息

介绍了农产品冷冻库网络控制系统的结构及其特点,设计了基于模糊自适应整定的PID控制器,实现了对农产品冷冻库网络控制系统的控制。基于TrueTime仿真工具箱的仿真实验表明:设计的农产品冷冻库网络控制系统具有响应速度快、稳定性强和抗干扰能力强等特点。

关键词：农产品冷冻库网络控制模糊自适应 PID TrueTime

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基于无线网络的农产品冷链物流温度监测系统研究

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农机化研究 2024年第2期46卷 212-215,220页

作者：冯双林程丽红广西工业职业技术学院南宁530003

介绍了农产品冷链物流温度监控的必要性,根据系统总体需求分析、总体架构、整体功能和硬件方案设计了监控系统,并基于GPRS网络和ZigBee无线网络设计了系统的硬件部分,从而实现了整个监测系统的目标。试验结果表明:系统可以实时显示冷链... 详细信息

介绍了农产品冷链物流温度监控的必要性,根据系统总体需求分析、总体架构、整体功能和硬件方案设计了监控系统,并基于GPRS网络和ZigBee无线网络设计了系统的硬件部分,从而实现了整个监测系统的目标。试验结果表明:系统可以实时显示冷链温箱内部温度,且能对异常温度进行报警,具有可行性和准确性。

关键词：农产品冷链物流温度监控无线网络

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2019—2022年聊城市食品和病例分离单增李斯特菌基于全基因组测序的分子特征及耐药性分析

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中国食品卫生杂志 2024年第3期36卷 292-299页

作者：钱璐张然梁胜楠崔方元程利红张香媛山东省聊城市疾病预防控制中心山东聊城252000 山东省聊城市人民医院山东聊城252000

目的基于全基因组测序(WGS)比较分析2019—2022年聊城市单核细胞增生李斯特菌(Lm)食品和病例分离株基因组特征、毒力性、耐药性以及遗传多样性。方法对聊城市33株市售食品和临床病例中Lm分离株开展抗生素敏感性试验和WGS。利用MGAP对WG... 详细信息

目的基于全基因组测序(WGS)比较分析2019—2022年聊城市单核细胞增生李斯特菌(Lm)食品和病例分离株基因组特征、毒力性、耐药性以及遗传多样性。方法对聊城市33株市售食品和临床病例中Lm分离株开展抗生素敏感性试验和WGS。利用MGAP对WGS数据进行拼接组装,对组装基因组进行基因预测和功能注释、MLST,制作cg MLST最小生成树图,并与美国国家生物信息中心(NCBI)上获取的18株国内外Lm构建wg-SNP进化树。结果33株Lm分离株的基因组大小为2.89~3.41 Mb,CG含量为37.81%~37.97%,可分为6个ST型(ST9、ST121、ST8、ST87、ST155、ST101),分别属于6个克隆复合群(CC9、CC121、CC8、CC87、CC155、CC101);分离株均携带fosX和mprF耐药基因,此外还携带lplA1、prsA2等其他18个毒力基因,有不同程度的毒力基因缺失情况。2株菌对四环素耐药,1株菌对林可霉素耐药。均携带毒力岛LIPI-1和LIPI-2,未检测到毒力岛LIPI-3和LIPI-4。wg-SNPs、cgMLST和基于单拷贝核心蛋白序列的系统发育树遗传进化分析显示,33株Lm分子分型呈现高度多样性,病例来源菌株与食品分离株亲缘关系密切,食品分离株与国外暴发分离株在进化关系上密切相关。结论山东省聊城市食品和病例中分离的单增李斯特菌均携带毒力基因,具有一定的潜在致病能力,耐药情况尚不严重。分子型别呈现出多样性,食品来源菌株和病例分离株具有较近的亲缘关系,提示市售食品有食源性感染的潜在风险。

关键词：单核细胞增生李斯特菌全基因组测序毒力耐药性食源性致病菌

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Observation on the Anesthesia Effect of Ultrasound-Guided Nerve Block for Elderly Patients with Lower Limb Fractures

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Proceedings of Anticancer Research 2021年第3期5卷 11-14页

作者： lihong cheng Shanzhi Luo Shuyang County Central Hospital Suqian 333600Jiangsu ProvinceChina

Objective:To explore the anesthesia effect of ultrasound-guided nerve block in elderly patients with lower limb fractures.Methods:From November 2017 to November 2020,50 elderly patients with lower limb fractures in our hospital were divided into experimental group(25 cases,general anesthesia+femoral nerve and sciatic nerve block)and control group(25 cases,general body anesthesia).Compare the MAP,HR,anesthesia effect,and adverse reactions between the two groups at each time period.Results:Before induction,the difference in MAP and HR between the two groups of patients did not form,p>0.05;the MAP and HR of the experimental group were compared with the control group at the time of skin incision,1 hour during the operation,and removal of the laryngeal mask,P<0.05;the time of extubation in the experimental group(14.28±3.18)min,awake time(5.57±1.32)min,orientation recovery time(11.89±2.23)min,propofol dosage(191.36±22.48)mg,remifentanil dosage(0.23±0.04)mg,Compared with the control group,P<0.05;the adverse reaction rate of the experimental group(8%,2/25)was lower than that of the control group(32%,8/25),P<0.05.Conclusion:The use of ultrasound-guided femoral nerve and sciatic nerve block for elderly patients with lower limb fractures can enhance the effect of anesthesia,effectively reduce the use of anesthetics,and have fewer adverse reactions.It is worthy of promotion.

关键词： Ultrasound guidance Nerve block Lower limb fracture Anesthesia effect

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Efficacy of suspended moxibustion stimulating Shenshu(BL23)and Guanyuan(CV4)on the amygdala-HPA axis in rats with kidney-Yang deficiency symptom pattern induced by hydrocortisone

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Journal of Traditional Chinese Medicine 2023年第1期43卷 113-123页

作者： MIN Youjiang YAO Haihua WANG Zhiqin LUO Kaitao SUN Jie YUAN Zheng WU Huiqi cheng lihong School of Traditional Chinese Medicine Nanchang Medical CollegeNanchang 330053China Traditional Chinese Medicine Department Shanghai Eighth People’s HospitalShanghai 200235China Acupuncture Department Affiliated Hospital of Jiangxi University of Traditional Chinese MedicineNanchang 330006JiangxiChina Acupuncture Department Jiaxing Hospital of Traditional Chinese MedicineJiaxing 314001China

OBJECTIVE:To investigated the effects of suspended moxibustion stimulating Shenshu(BL23)and Guanyuan(CV4)acupoints on the amygdala and HPA axis in our rat model and elucidated the possible molecular mechanisms of moxibustion on kidney-Yang deficiency symptom pattern(KYDS).METHODS:Sixty male Sprague Dawley rats were randomly divided into a control group(n=12)and an experimental group(n=48).Rats in the experimental group were given intramuscular injections of hydrocortisone to establish a KYDS model.The 48 rats successfully modeled were then randomly divided into a model group(model,n=12),a carbenoxolone intraperitoneal injection group(CBX,n=12),a moxibustion group(moxi,n=12),and a moxi+CBX group(n=12).In the moxi,the Shenshu(BL23)and Guanyuan(CV 4)acupoints were treated with moxibustion for 14 d.After treatment,measures were taken of serum levels of corticosterone(CORT),adrenocorticotropic hormone(ACTH),and corticotropinreleasing hormone(CRH).The expression of mineralocorticoid receptors(MRs),glucocorticoid receptors(GRs),11beta-hydroxysteroid dehydrogenase type 1(11β-HSD1),CRH,and ACTH in the rats’amygdala,hypothalamus,or pituitary(as appropriate)was detected.Data were analyzed using one-way analysis of variance.RESULTS:Compared with those of the control group,the serum levels of CRH,ACTH,and CORT;the mRNA and protein expressions of MR,GR,and 11β-HSD1 in the amygdala;the mRNA and protein expressions of 11β-HSD1 in the hypothalamus;the CRH mRNA expression in the amygdala and hypothalamus;and the ACTH mRNA expression in the pituitary of the rats in the model group were all significantly decreased(P<0.05 or 0.01).After treatment with moxibustion,all the aforementioned observation indices except for 11β-HSD1 m RNA expression were ameliorated compared with those in the model group(P<0.05 or 0.01).CONCLUSIONS:Suspended moxibustion can effectively improve the serum levels of ACTH,CRH,and CORT and can up-regulate the mRNA and protein expressions of MR,GR,11β-HSD1,CRH,and ACTH in the amygdala and hypothalamus of KYDS rats

关键词： moxibustion kidney-Yang deficiency amygdala hypothalamus receptors,mineralocorticoid receptors,glucocorticoid 11-beta-hydroxysteroid dehydrogenase type 1

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新文科语境下新闻传播人才培养

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社会科学战线 2022年第4期 185-191,282页

作者：程丽红辽宁大学新闻与传播学院辽宁沈阳110136

教育部关于新文科建设的重大举措并非孤立行为,而是中国高等教育学科体系全面创新系统工程的重要一环。新文科建设的本质是学科系统的开放,并以此为基础,借助学科之间的深度融合、跨界赋能,实现文科的科学化,提升文科发展质量。新闻传... 详细信息

教育部关于新文科建设的重大举措并非孤立行为,而是中国高等教育学科体系全面创新系统工程的重要一环。新文科建设的本质是学科系统的开放,并以此为基础,借助学科之间的深度融合、跨界赋能,实现文科的科学化,提升文科发展质量。新闻传播学科应把握新文科发展的契机,吸纳新生动力、新鲜血液,为新闻传播卓越人才的培养提供重要保障。首先,加强系统开放,完善新闻传播人才培养体制机制建设;其次,深化跨界赋能,推动新闻传播学科创新融合。此外,融通专业知识与人文精神,提升新闻传播学人才培养质量。而新闻传播学新文科建设的“命门”在守根固本。新闻传播教育体系本身的完整性是前提,同时需要定位本体,廓清学科边界,为学科融通奠定基础。

关键词：新文科新闻传播学人才培养实践创新

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Synthesis, spectral properties of aluminum polymeric phthalocyanine carboxyl with low aggregation in aqueous solution

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Chinese Science Bulletin 2008年第20期53卷 3159-3163页

作者： ZHAO Peng NIU lihong ZHONG cheng DONG SiDa ZHANG FuShi The Key Laboratory of Organic Photoelectrons and Molecular Engineering of Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 China

A water soluble poly-[tetrakis-(2,3-dicarboxylate phenoxy) methyl methan] aluminum phthalocyanine (AlPPc.(COOH)x) has been synthesized from the cyclization of tetranuclear phthalonitrile and successive hydrolysis of cyano in alkaline solution. The absorption spectra showed low aggregation of this compound in pH 9.18 buffer than that of existing water soluble phthalocyanine compounds. With the addition of Triton X 100, an enhancement of fluorescence emission with quantum yield from 0.4 to 0.83 was observed; contrarily, it was thoroughly quenched by the addition of CATB in suit. A longer life time of singlet state was also detected in presence of Triton X 100. The result indicates that AlPPc.(COOH)x is desired to investigate in fluorescent probe or in fluorescence imaging diagnose.

关键词：铝酞菁染料聚合体水溶性荧光性合成

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