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Science Bulletin 2017年第22期62卷 1525-1529页

作者： Honggang Ye Zhicheng Su Fei Tang changcheng zheng Guangde Chen Jian Wang Shijie Xu Department of Physics and Shenzhen Institute of Research and Innovation (HKU-SIRI) The University of Hong Kong Hang Kong China Department of Applied Physics Xi'an Jiaotong University Xi'an 710049 China Mathematics and Physics Centre Department of Mathematical Sciences Xi'an Jiaotong-Liverpool University Suzhou 215123 China

It is firmly demonstrated in experiment that the self-absorption(SA) effect can lead to the extinction of the zero-phonon line and the first-order longitudinal optical phonon sideband of free excitonic luminescence of ZnO at room temperature. Moreover, effectiveness degree of SA effect is found to be dependent on both absorption coefficient and travelling distance of emitted photons, as well as even lattice temperature, which is uniquely reflected by the redshift amount in emission peak in ZnO. It is also unambiguously proved that the SA effect still strictly obeys the Beer-Lambert law of absorption. This work not only uncovers the long-term puzzle of significant redshift of emission peak of ZnO at higher temperatures, but also shows that the SA effect may have to be carefully taken into consideration in the study of spontaneous emission, laser and relevant optoelectronic processes in luminescent materials and optoelectronic devices.

关键词： Seif-absorption Excitonic luminescence Two-photon absorption Phonon-assistecl luminescence

High-excited-state splitting and multimode vibrational coupling in Mn^(4+)-activated fluoride phosphor

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 95-101页

作者： Debao Zhang Wanggui Ye Xuguang Cao Ji Zhou Fei Tang changcheng zheng Jiqiang Ning Shijie Xu Department of Optical Science and Engineering School of Information Science and TechnologyFudan University Shanghai 200438China Jiangsu Key Laboratory of Advanced Laser Materials and Devices Schoolof Physics and Electronic Engineering Jiangsu Normal UniversityXuzhou 221116China Division of Natural and Applied Sciences Duke Kunshan UniversityKunshan 215316China

Excited-states play a crucial role in the optical absorption and luminescence of solids and hence their accurate information is highly desired. Herein, we attempt to seize the excited-states information of Mn^(4+)ions in K_(2)SiF_(6) microcrystals via measuring and calculating their variable-temperature photoluminescence excitation(PLE) spectra. At cryogenic temperatures, an unpredicted splitting of the high-excited-state is observed. Moreover, the two-split high-excited-state levels are further revealed to primarily couple with the two hyperfine split modes of quasi-localized ν2 vibration in the distorted Mn-F_(6) octahedral configuration,whereas the coupling strengths are found to be substantially different from each other. The slightly split vibrational mode is firmly supported by the low-temperature Raman spectra. Jahn-Teller lattice distortion is believed to be responsible for the observed splitting of the electronic high-excited-state and the quasi-localized vibrational mode.

关键词： splitting of excited-state photoluminescence excitation spectrum electron-phonon coupling Jahn-Teller effect

Realization of high-performance tri-layer graphene saturable absorber mirror fabricated via a one-step transfer process

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Journal of Semiconductors 2020年第1期41卷 83-87页

作者： Cheng Jiang Xu Wang Jian Liu Jiqiang Ning changcheng zheng Xiaohui Li Ziyang Zhang Key Laboratory of Nanodevice and Applications Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Vacuum Interconnected Nanotech Workstation Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Division of Natural and Applied Sciences Duke Kunshan UniversityKunshan 215316China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China Nano Science and Technology Institute University of Science and Technology of ChinaSuzhou 215123China

Graphene,as a saturable absorber(SA),has attracted much attention for its application in ultrashort pulse fiber lasers due to its ultrafast interband carrier relaxation and ultra-broadband wavelength ***,during the stacking process of monolayer graphene layer,the induced nonuniform contact at the interface of graphene layers deteriorate the device ***,we report the fabrication of graphene saturable absorber mirrors(SAMs)via a one-step transfer process and the realization of the much enlarged modulation depth and the much reduced nonsaturable loss with tri-layer graphene(TLG)than single-layer graphene(SLG)due to the improved uniform contact at the ***,the operation of 1550 nm mode-locked Er-doped fiber laser with the TLG SAM exhibits excellent output characteristics of the maximum output power of 9.9 mW,a slope efficiency of 2.4%and a pulse width of 714 *** findings are expected to pave the way toward high-performance ultrashort pulse fiber lasers based on graphene SAs.

关键词： graphene SAMs mode-locked lasers nonlinear absorption characteristics

STUDY ON THE DECOLORIZATION OF D-RIBOSE ZYMOTIC FLUID BY RESIN ADSORPTION

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Chinese Journal of Reactive Polymers 1999年第1期8卷 61-67页

作者： zheng changcheng GUO Xianzhi DENG Guocai YANG Sihai CHEN Rongti Department of Chemistry Nankai UniversityTianjin 300071

In this paper, effects on of six type of resins the decolorization of D-ribosezymotic fluid have been studied for the fist time. The results show that resinNKA-II has the best effect. the decolorization rate of D-ribose zymotic fluid is91% at velocity of 1.0BV/hr and 25℃, the adsorption capacity can reach up to5.7BV. The effects of adsorption conditions as well as conditions of resinregeneration on the resin decolorization capability were also studied.

关键词： D-ribose Decolorization Resin adsorption

STUDY ON THE SEPARATION OF PENTOSE AND HEXOSE FROM GLUCOSE YEAST WATER

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Chinese Journal of Reactive Polymers 2000年第2期9卷 164-168页

作者： zheng changcheng ZHANG Jinfeng LU Yan DENG Guocai CHEN Rongti Department of Chemistry Nankai UniversityTianjin 300071P.R China

D-ribose is a unique, 5-carbon sugar that occurs naturally in all living cells. D-ribose has been used as a staring material for preparation of some certain medicines or just as a new nutraceutical that helps the body naturally restore its energy level. The fermentative processes are the best for their relatively simple series of production steps and relatively cheap starting materials. However, because of the many impurities in glucose yeast water and its dark color, pretreatment and purification must be done to the fluid before D-ribose can be separated. In this paper, separation and purification of D-ribose was carried out using cation exchange resins, of which Ca2+ exchange resin had the best effect. The optimal condition for adsorption is a flow velocity of 0.5BV/h at adsorption temperature of 25℃. The optimal condition for desorption is a flow velocity of 0.5 BV/h at desorption temperature of 80℃.

关键词： Glucose yeast water Ion exchange resin Separation

Risk factors of CMV infection in patients after umbilical cord blood transplantation: a multicenter study in China

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Chinese Journal of Cancer Research 2013年第6期25卷 695-703页

作者： Juan Tong Zimin Sun Huilan Liu Liangquan Geng changcheng zheng Baolin Tang Kaidi Song Wen Yao Xin Liu Shandong University School of Medicine Department of Hematology Anhui Provincial HospitalAnhui Medical University

Objective： This retrospective study examined risk factors for cytomegalovirus （CMV） infection after umbilical cord blood transplantation （UCBT） and the impact of CMV infection on patient survival. Methods： In all 176 patients, plasma CMV DNA was negative prior to the transplantation, and examined twice a week for 100 d, and then once weekly for additional 300 d. Preemptive antiviral therapy （ganciclovir or foscarnet） was started in patients with 〉 1,000/mL copies of CMV DNA but no full-blown CMV disease, and was discontinued upon two consecutive negative reports of blood CMV DNA test. The survival and risk factors for CMV infection or disease were examined using logistic regression. Results： CMV infection developed in 71% （125/176） of the patients, with a median onset of 32 d. Four patients （2.3%） developed CMV disease. Neither the 5-year overall survival （OS） nor event-free survival （EFS） differed significantly in infected patients vs. those with no infection （59.4% vs. 64.8%, P=0.194; 53.4% vs. 59.1%, P=0.226）. A stepwise multivariate analysis indicated an association of CMV infection with age, high-dose glucocorticoids, the number of transplanted CD34^＋ cells, and the number of platelet transfusion, but not with gender, the conditioning regimen, and the day of neutrophil recovery and chronic graft-versus- host disease （cGVHD）. Conclusions： CMV infection is very common after UCBT, but does not seem to affect long-term survival with preemptive antiviral treatment.

关键词： Cytomegalovirus (CMV) umbilical cord blood transplantation (UCBT) risk factor

2022年欧洲白血病网络急性髓系白血病诊治指南更新要点解读

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白血病．淋巴瘤 2022年第11期31卷 641-643页

作者：冯尚龙郑昌成中国科学技术大学附属第一医院(安徽省立医院)血液科合肥230001

2010年以及2017年版的欧洲白血病网络(ELN)急性髓系白血病(AML)诊治指南已在临床广泛应用。随着对AML分子生物学机制的进一步认识和临床靶向药物应用的巨大进步,2022年版ELN AML指南已在Blood杂志在线发表。文章对2022年版指南的更新要... 详细信息

2010年以及2017年版的欧洲白血病网络(ELN)急性髓系白血病(AML)诊治指南已在临床广泛应用。随着对AML分子生物学机制的进一步认识和临床靶向药物应用的巨大进步,2022年版ELN AML指南已在Blood杂志在线发表。文章对2022年版指南的更新要点进行相关解读。

关键词：白血病髓样急性欧洲白血病网络指南

Quantum cascade superluminescent light emitters with high power and compact structure

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Journal of Semiconductors 2020年第1期41卷 78-82页

作者： Jialin Sun Chuncai Hou Hongmei Chen Jinchuan Zhang Ning Zhuo Jiqiang Ning changcheng zheng Zhanguo Wang Fengqi Liu Ziyang Zhang School of Nano Technology and Nano Bionics University of Science and Technology of ChinaHefei 230026China Key Laboratory of Semiconductor Materials Science Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China The 718th Research Institute of China Shipbuilding Industry Corporation Handan 056027China Key Laboratory of Nanodevice and Applications Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Vacuum Interconnected Nanotech Workstation Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Division of Natural and Applied Sciences Duke Kunshan UniversityKunshan 215316China

Quantum cascade(QC)superluminescent light emitters(SLEs)have emerged as desirable broadband mid-infrared(MIR)light sources for growing number of applications in areas like medical imaging,gas sensing and national ***,it is challenging to obtain a practical high-power device due to the very low efficiency of spontaneous emission in the intersubband transitions in QC *** a design of^5μm SLEs is demonstrated with a two-phonon resonancebased QC active structure coupled with a compact combinatorial waveguide structure which comprises a short straight part adjacent to a tilted stripe and to a J-shaped *** as-fabricated SLEs achieve a high output power of 1.8 mW,exhibiting the potential to be integrated into array devices without taking up too much chip *** results may facilitate the realization of SLE arrays to attain larger output power and pave the pathway towards the practical applications of broadband MIR light sources.

关键词： quantum cascade superluminescent diode mid-wave infrared

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三元复合驱注入方式与采收率探究

石化技术 2019年第4期26卷 15-15,21页

作者：郑长城大庆油田采油一厂

驱替剂的作用是使残余凝胶体在岩石孔道内就地混凝,可通过混凝剂筛选实验研制出来;混凝剂的注入参数需要优化,可通过岩心模拟评价实验来完成。通过实验可以得出以下2条结论:第一,区块的调驱液波及系数和洗油效率可以得到改善,从而使得... 详细信息

驱替剂的作用是使残余凝胶体在岩石孔道内就地混凝,可通过混凝剂筛选实验研制出来;混凝剂的注入参数需要优化,可通过岩心模拟评价实验来完成。通过实验可以得出以下2条结论:第一,区块的调驱液波及系数和洗油效率可以得到改善,从而使得采收率进一步提高。第二,铁类溶液是作为混凝剂的最佳配方。

关键词：驱替剂残余凝胶体铁

Sr_(2)LuNbO_(6):Mn^(4+)深红荧光粉的光学性质:晶体场劈裂和多模振动耦合

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Science China Materials 2024年第3期67卷 939-945页

作者：周广涵张德保唐飞郑昌成宁吉强徐士杰 Department of Optical Science and Engineering School of Information Science and TechnologyFudan UniversityShanghai 200438China School of Physics and Electronic Engineering Jiangsu Normal UniversityXuzhou 221116China Division of Natural and Applied Sciences Duke Kunshan UniversityKunshan 215316China

本研究利用光致发光(PL)、光致发光激发(PLE)、时间分辨PL和拉曼光谱技术等,详细研究了通过熔盐固相法合成的Sr_(2)LuNbO_(6):Mn^(4+)深红荧光粉的光学性质.在室温下,样品的PL光谱呈现出阶梯状谱形.然而,在低温下,测量的PL光谱由两组多... 详细信息

本研究利用光致发光(PL)、光致发光激发(PLE)、时间分辨PL和拉曼光谱技术等,详细研究了通过熔盐固相法合成的Sr_(2)LuNbO_(6):Mn^(4+)深红荧光粉的光学性质.在室温下,样品的PL光谱呈现出阶梯状谱形.然而,在低温下,测量的PL光谱由两组多模振动电子发光谱线组成.基于变温PL光谱和拉曼光谱,我们识别出双零声子谱线以及两组恒定能量间隔为~2.8 meV的多模声子伴线.这项研究首次发现Mn^(4+)离子的^(2)E_(g)激发态能级在氧化物八面体晶格中具有~2.8 meV能量差的劈裂,并证实多种振动模式深度参与Mn^(4+)离子的振动电子发光.

关键词： oxide phosphor deep red luminescence Mn^(4+)ion excited-state splitting impurity-lattice coupling