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The Up-conversion Laser Properties of a Non-polar Organic Dye and the Influence of Solvents and Pumping Wavelengths

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Chinese Chemical Letters 2006年第1期17卷 81-84页

作者： Xiao Qiang YU xian ZHANG Gui Bao xu Hua Ping ZHAO Wei HE Zong Shu SHAO xian gang xu Min Hua JIANG The National Key Lab of Crystal Materials Shandong University Jinan 250100

A non-polar organic dye, E, E-1, 4-bis[4＇-（N,N-dibutylamino）styryl]-2,5-dimethoxybenzene （DBASDMB）, has been synthesized and characterized, and its structure has been determined. Pumped with a 200fs pulse this dye showed the up-conversion laser properties. The influences of various organic solvents and different pumping wavelength on the laser properties have been demonstrated.

关键词： Up-conversion laser two-photon absorption non-polar organic dye.

Efficiency droop in InGaN/GaN-based LEDs with a gradually varying In composition in each InGaN well layer

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Chinese Physics B 2022年第1期31卷 585-589页

作者： Shang-Da Qu Ming-Sheng xu Cheng-Xin Wang Kai-Ju Shi Rui Li Ye-Hui Wei xian-gang xu Zi-Wu Ji School of Microelectronics Institute of Novel SemiconductorsShandong UniversityJinan 250100China Shandong Inspur Huaguang Optoelectronics Co. Ltd.Weifang 261061China

Temperature-dependent and driving current-dependent electroluminescence spectra of two different InGaN/GaN multiple quantum well structures SA and SB are investigated,with the In composition in each well layer(WL)along the growth direction progressively increasing for SA and progressively decreasing for *** results show that SB exhibits an improved efficiency droop compared with *** phenomenon can be explained as follows:owing to the difference in growth pattern of the WL between these two samples,the terminal region of the WL in SB contains fewer In atoms than in SA,and therefore the former undergoes less In volatilization than the latter during the waiting period required for warming-up due to the difference in the growth temperature between well and barrier *** results in SB having a deeper triangular-shaped potential well in its WL than SA,which strongly confines the carriers to the initial region of the WL to prevent them from leaking to the p-GaN side,thus improving the efficiency ***,the improvement in the efficiency droop for SB is also partly attributed to its stronger Coulomb screening effect and carrier localization effect.

关键词： InGaN/GaN asymmetric triangular multiple quantum wells structural and electroluminescence properties efficiency droop

Combined effects of carrier scattering and Coulomb screening on photoluminescence in InGaN/GaN quantum well structure with high In content

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Chinese Physics B 2021年第4期30卷 530-534页

作者： Rui Li Ming-Sheng xu Peng Wang Cheng-Xin Wang Shang-Da Qu Kai-Ju Shi Ye-Hui Wei xian-gang xu Zi-Wu Ji School of Microelectronics Shandong UniversityJinan 250100China Shandong Inspur Huaguang Optoelectronics Co. Ltd.Weifang 261061China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China

Photoluminescence(PL) spectra of two different green InGaN/GaN multiple quantum well(MQW) samples S1 and S2,respectively with a higher growth temperature and a lower growth temperature of InGaN well layers are analyzed over a wide temperature range of 6 K-3 30 K and an excitation power range of 0.001 mW-75 *** excitation power-dependent PL peak energy and linewidth at 6 K show that in an initial excitation power range,the emission process of the MQW is dominated simultaneously by the combined effects of the carrier scattering and Coulomb screening for both the samples,and both the carrier scattering effect and the Coulomb screening effect are stronger for S2 than those for S1;in the highest excitation power range,the emission process of the MQWs is dominated by the filling effect of the high-energy localized states for S1,and by the Coulomb screening effect for *** behaviors can be attributed to the fact that sample S2 should have a higher amount of In content in the InGaN well layers than S1 because of the lower growth temperature,and this results in a stronger component fluctuation-induced potential fluctuation and a stronger well/barrier lattice mismatchinduced quantum-confined Stark *** explanation is also supported by other relevant measurements of the samples,such as temperature-dependent peak energy and excitation-power-dependent internal quantum efficiency.

关键词： photoluminescence carrier localization effect internal quantum efficiency growth temperature

Metallorganic Vapor Phase Epitaxy of(AlGa)InP on GaAs at Atmospheric Pressure

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Journal of Materials Science & Technology 1993年第6期9卷 427-430页

作者： Hongwen REN Baibiao HUANG Shuqin YU xian’gang xu Shiwen LIU Minhua JIANG Institute of Crystal Materials,Shandong University,Jinan,250100,China

High quality (AlGa)InP epilayers lattice matched on GaAs substrates were grown by atmospheric pressure metallorganic vapor phase epitaxy (AP-MOVPE).The relationship between surface morphologies and lattice mismatches was *** influence of Al incorporation to the photoluminescence and electronic properties of AlGaInP was *** applicability of growth at atmospheric pressure and the passivation of Zn in AlGaInP were discussed.

关键词： MOVPE GalnP mismatching photolummescence doping

Insights into spinal muscular atrophy from molecular biomarkers

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Neural Regeneration Research 2025年第7期20卷 1849-1863页

作者： Xiaodong Xing Xinzhu Liu xiandeng Li Mi Li xian Wu Xiaohui Huang Ajing xu Yan Liu Jian Zhang Department of Clinical Pharmacy Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina College of Pharmacy Chongqing Medical UniversityChongqingChina

Spinal muscular atrophy is a devastating motor neuron disease characterized by severe cases of fatal muscle *** is one of the most common genetic causes of mortality among infants aged less than 2 *** research is currently receiving more attention,and new candidate biomarkers are constantly being *** review initially discusses the evaluation methods commonly used in clinical practice while briefly outlining their respective pros and *** also describe recent advancements in research and the clinical significance of molecular biomarkers for spinal muscular atrophy,which are classified as either specific or non-specific *** review provides new insights into the pathogenesis of spinal muscular atrophy,the mechanism of biomarkers in response to drug-modified therapies,the selection of biomarker candidates,and would promote the development of future ***,the successful utilization of biomarkers may facilitate the implementation of gene-targeting treatments for patients with spinal muscular atrophy.

关键词： biomarkers disease progression gene-targeting therapy neurofilaments Nusinersen spinal muscular atrophy(SMA) survival motor neuron therapeutic evaluation treatment outcomes

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地塞米松抑制胆管瘢痕成纤维细胞的体外研究

中国现代医学杂志 2017年第17期27卷 7-12页

作者：李克跃石承先汤可立刘振华黎涛张帅民徐贤刚贵州省人民医院肝胆外科贵州贵阳550002

目的研究地塞米松(DEX)对体外培养的兔胆管瘢痕模型成纤维细胞(MF)中Ⅰ型胶原、结缔组织生长因子(CTGF)及第10号染色体丢失的张力蛋白同源的磷酸酶基因(PTEN)表达的影响。方法对家兔采用切开再吻合方法复制胆管瘢痕模型并获取MF,经细胞... 详细信息

目的研究地塞米松(DEX)对体外培养的兔胆管瘢痕模型成纤维细胞(MF)中Ⅰ型胶原、结缔组织生长因子(CTGF)及第10号染色体丢失的张力蛋白同源的磷酸酶基因(PTEN)表达的影响。方法对家兔采用切开再吻合方法复制胆管瘢痕模型并获取MF,经细胞鉴定后对MF给予不同浓度的DEX(0.00、0.01、0.05和0.25 mg/ml)干预48 h,活细胞计数法试剂盒测定各组细胞增殖水平;实时聚合酶链反应检测各组细胞Ⅰ型胶原、CTGF和PTEN m RNA表达水平;Western blot检测各组细胞Ⅰ型胶原和PTEN蛋白表达水平。结果在DEX干预48 h后,MF增殖受抑制,细胞Ⅰ型胶原、CTGF m RNA和蛋白表达下调,PTEN m RNA和蛋白表达上调(P<0.05),呈浓度依耐性。结论 DEX可能具有抑制胆管瘢痕及良性胆道狭窄形成的作用,其机制之一可能与MF中Ⅰ型胶原、CTGF及PTEN的调控有关。

关键词：胆管瘢痕成纤维细胞抑制体外地塞米松

A FEASIBLE DIRECTION ALGORITHM WITHOUT LINE SEARCH FOR SOLVING MAX-BISECTION PROBLEMS

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Journal of Computational Mathematics 2005年第6期23卷 619-634页

作者： Feng-min xu Cheng-xian xu Hong-gang xue Department of Mathematics of Faculty of Science Xi'an Jiaotong University Xi'an 710049 China

This paper concerns the solution of the NP-hard max-bisection problems. NCP functions are employed to convert max-bisection problems into continuous nonlinear programming problems. Solving the resulting continuous nonlinear programming problem generates a solution that gives an upper bound on the optimal value of the max-bisection problem. From the solution, the greedy strategy is used to generate a satisfactory approximate solution of the max-bisection problem. A feasible direction method without line searches is proposed to solve the resulting continuous nonlinear programming, and the convergence of the algorithm to KKT point of the resulting problem is proved. Numerical experiments and comparisons on well-known test problems, and on randomly generated test problems show that the proposed method is robust, and very efficient.

关键词： Max-Bisection problem Feasible direction algorithm NCP function Convergence

盾构隧道施工扰动对隧道与车站地震响应的影响分析

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地震工程学报 2025年第1期47卷 69-81页

作者：加瑞杨岗郑刚李青茁许敬明天津大学建筑工程学院天津300350 天津大学滨海土木工程结构与安全教育部重点实验室天津300350

盾构隧道施工扰动会改变隧道周围土体的应力状态和力学性质,从而影响隧道与车站后期的地震响应。通过数值模拟,分析不同程度的应力状态改变和剪切模量衰减对地震时隧道周围土体、管片结构以及车站结构地震响应的影响。结果表明:(1)应力... 详细信息

盾构隧道施工扰动会改变隧道周围土体的应力状态和力学性质,从而影响隧道与车站后期的地震响应。通过数值模拟,分析不同程度的应力状态改变和剪切模量衰减对地震时隧道周围土体、管片结构以及车站结构地震响应的影响。结果表明:(1)应力状态改变程度越大(地层应力释放率越大),隧道周围土体的初始剪应力越大,隧道底部土体的剪应变越大,超静孔隙水压力越大;同时,地震引起的管片弯矩和轴力越大(应力释放率30%时地震引起的左拱肩峰值管片弯矩和轴力增量分别是应力释放率10%时的165%和527%),车站侧墙和柱的相对水平位移越大。(2)剪切模量衰减程度越大,隧道周围土体的剪切模量越小,隧道周围土体越软,隧道底部土体的剪应变越大,超静孔隙水压力越大;同时,地震引起的管片弯矩和轴力越小(模量衰减大时地震引起的左拱肩峰值管片弯矩和轴力增量分别是模量无衰减时的67%和40%),车站侧墙和柱的相对水平位移越小。因此,盾构隧道的施工扰动程度对后期隧道与车站的地震响应有明显影响,在隧道与车站的抗震设计时应考虑盾构隧道前期施工对周围土体应力状态及力学性质改变的影响。

关键词：盾构隧道施工扰动应力状态模量衰减地震响应

Spectrophotometric Determination of Trace Chromium(VI) in Mass Chromium(III)

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Chinese Chemical Letters 2001年第7期12卷 635-636页

作者： Zi gang xu xian Hong WEN Qing Zhou WU Center of Analysis&Testing Zhejiang UniversityHangzhou 310027

The method for the sepration and determination of trace Cr(VI) exiting in mass Cr(III) has been researched. The method is highly sensitive and less interference, but is simple and useful for analysis trace Cr(VI).

关键词： Spectrophotometric Cr(VI) Cr(III) diphenyl carbazide(DPC) 4-methyl-benzene sulfonic acid