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Visual observation of photonic Floquet–Bloch oscillations

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Light(Science & Applications) 2024年第5期13卷 921-929页

作者： zhen Zhang Yuan Li Xiankai Sun Xuewen shu Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhanHubei 430074China Department of Electronic Engineering The Chinese University of Hong KongShatinNew TerritoriesHong Kong SARChina

Bloch oscillations(BOs),an important transport phenomenon,have been studied extensively in static systems but remain mysterious in Floquet ***,by harnessing notions from photonic analogy,we propose a generalization of the existing BOs in photonic Floquet lattices,namely the“photonic Floquet–Bloch oscillations”,which refer to rescaled photonic Bloch oscillations with a period of extended least common multiple of the modulation period and the Bloch oscillation ***,we report the first visual observation of such photonic Floquet–Bloch oscillations(FBOs)by employing waveguide fluorescence *** significantly,the FBOs surpass the existing BOs in Floquet systems and exhibit exotic properties on their own,including fractal spectrum and fractional Floquet *** new transport mechanism offers an intriguing method of wave manipulation that may contribute to rapidly developing fields in photonics,condensed matter physics,and quantum physics.

关键词： Bloch analogy generalization

Propagation dynamics of dipole breathing wave in lossy nonlocal nonlinear media

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Chinese Physics B 2022年第1期31卷 273-280页

作者： Jian-Li Guo zhen-Jun Yang Xing-liang Li shu-Min Zhang College of Physics Hebei Key Laboratory of Photophysics Research and ApplicationHebei Normal UniversityShijiazhuang 050024China

In the framework of nonlinear wave optics,we report the evolution process of a dipole breathing wave in lossy nonlocal nonlinear media based on the nonlocal nonlinear Schrödinger *** analytical expression of the dipole breathing wave in such a nonlinear system is obtained by using the variational *** advantage of the analytical expression,we analyze the influences of various physical parameters on the breathing wave propagation,including the propagation loss and the input power on the beam width,the beam intensity,and the wavefront ***,the corresponding analytical solutions are *** validity of the analysis results is verified by numerical *** study provides some new insights for investigating beam propagation in lossy nonlinear media.

关键词： breathing wave propagation variational method

TENSILE　DEFORMATION　AND　FRACTURE　BEHAVIOR　OF　Ti_3Al-Nb　ALLOY　AT　HIGH　TEMPERATURE

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中国有色金属学会会刊：英文版 1997年第1期7卷 76-82页

作者： Wu, Ying zhen, liang Yang, Dezhuang Harbin Inst of Technology Harbin China

ＴＥＮＳＩＬＥＤＥＦＯＲＭＡＴＩＯＮＡＮＤＦＲＡＣＴＵＲＥＢＥＨＡＶＩＯＲＯＦＴｉ３ＡｌＮｂＡＬＬＯＹＡＴＨＩＧＨＴＥＭＰＥＲＡＴＵＲＥ①ＷｕＹｉｎｇ，ＺｈｅｎＬｉａｎｇ，ＹａｎｇＤｅｚｈｕａｎｇＳｃｈｏｏｌｏｆＭ... 详细信息

ＴＥＮＳＩＬＥＤＥＦＯＲＭＡＴＩＯＮＡＮＤＦＲＡＣＴＵＲＥＢＥＨＡＶＩＯＲＯＦＴｉ３ＡｌＮｂＡＬＬＯＹＡＴＨＩＧＨＴＥＭＰＥＲＡＴＵＲＥ①ＷｕＹｉｎｇ，ＺｈｅｎＬｉａｎｇ，ＹａｎｇＤｅｚｈｕａｎｇＳｃｈｏｏｌｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎ...

关键词： Ti 3Al Nb alloy tensile deformation fracture

Demographic Genetic Structure of Cryptomeria japonica var. sinensis in Tianmushan Nature Reserve, China

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Journal of Integrative Plant Biology 2008年第9期50卷 1171-1177页

作者： Yan Chen shu-zhen Yang Ming-shui Zhao Bi-Ye Ni liang Liu Xiao-Yong Chen Department of Environmental Sciences Shanghai Key Laboratory for Ecological Processes and Restoration in Urban Areas East China Normal University Shanghai 200062 China Tiantong State Field Observation and Research Station of Forest Ecosystems Shanghai 200062 China Zhejiang West Tianmushan Nature Reserve Management Bureau Lin'an 311311 China

Genetic changes over space and time provide insights into the relative roles of evolutionary factors in shaping genetic patterns within plant populations. However, compared with spatial genetic structure, few studies have been conducted on genetic changes over time. In this study, we used six polymorphic microsatellite loci to assess genetic variation of six size-classes of the population of Liushan, Cryptomeriajaponica var. sinensis, in the Tianmushan National Nature Reserve, whose origin was debatable. The mean number of alleles per locus and expected heterozygosity were 4.583 and 0.5999 respectively, lower than other conifers with the same life history characteristics. FST was 0.0024-0.003, and the pairwise test revealed no significant differentiation in any pair of size classes. Significant heterozygosity excesses were detected in five size classes except the oldest one, indicating bottleneck event（s）. The above results support the hypothesis that Tianmushan population was introduced and followed by natural regeneration.

关键词： Cryptomeriajaponica var. sinensis founder effect genetic variation microsatellites size class.

内蒙古农牧交错区典型黑土坡耕地土壤侵蚀空间分布特征

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水土保持研究 2025年第1期32卷 13-20页

作者：邹惠杰刘刚舒成博孙波刘亚张琼郭珍中国科学院教育部水土保持与生态环境研究中心黄土高原土壤侵蚀与旱地农业国家重点实验室陕西杨凌712100 中国科学院水利部水土保持研究所陕西杨凌712100 中国科学院大学北京100049 西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室陕西杨凌712100 四川华标测检测技术有限公司成都610097

[目的]定量了解内蒙古典型黑土区土壤侵蚀速率,探究该区域土壤侵蚀空间分布特征,阐明土壤侵蚀坡面和区域空间分布规律,以期为区域水土流失治理提供参考。[方法]采集内蒙古农牧交错区(海拉尔区、额尔古纳市和牙克石市)典型黑土坡耕地的... 详细信息

[目的]定量了解内蒙古典型黑土区土壤侵蚀速率,探究该区域土壤侵蚀空间分布特征,阐明土壤侵蚀坡面和区域空间分布规律,以期为区域水土流失治理提供参考。[方法]采集内蒙古农牧交错区(海拉尔区、额尔古纳市和牙克石市)典型黑土坡耕地的土壤样品,利用137 Cs示踪技术计算各采样点土壤侵蚀速率,结合小波分析的方法研究土壤侵蚀在坡面的分布特征。[结果](1)3个坡面所有采样点137 Cs含量均小于背景值(1984.24 Bq/m^(2)),表现为所有坡面土壤流失。(2)3个地区的采样坡面平均侵蚀速率表现为:海拉尔〔6533.37 t/(km^(2)·a)〕>额尔古纳〔4174.35 t/(km^(2)·a)〕>牙克石〔2765.87 t/(km^(2)·a)〕。相同坡面的3个纵向断面的平均侵蚀速率相近,同一断面侵蚀速率的变异程度较高。(3)土壤侵蚀速率沿坡长呈强弱交替的周期性变化,但周期长度并不固定。大部分纵向断面存在周期长度为80~160 m和160~200 m的大小两个周期。部分纵向断面只存在一个周期长度为100~120 m的周期。[结论]该地区土壤侵蚀在坡面尺度表现为全坡面侵蚀且在纵向呈现周期性特征,在区域尺度呈现从东到西逐渐增加趋势。

关键词：土壤侵蚀典型黑土农牧交错带小波分析

Surgical therapy and prognosis of sarcomatoid carcinoma of the gallbladder

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Hepatobiliary & Pancreatic Diseases International 2010年第2期9卷 175-179页

作者： Hu, zhen-Hua Li, Zhi-Wei Shen, liang Zhang, Min zheng, shu-Sen Zhejiang Univ Minist Publ Hlth Affiliated Hosp 1Div Hepatobiliary & Pancreat Su Key Lab Combined Multiorgan TransplantatSch Med Hangzhou 310003 Zhejiang Peoples R China Zhejiang Univ Sch Med Affiliated Hosp 1 Key Lab Organ Transplantat Zhejiang Prov Hangzhou 310003 Zhejiang Peoples R China

BACKGROUND: Sarcomatoid carcinoma of the gallbladder is rare and its characteristics are poorly understood. This study aimed to understand the behavior and prognosis of sarcomatoid carcinoma of the gallbladder as well as its clinical manifestations and survival rate of patients after radical or palliative surgery, and to review the reported data worldwide and our 10 patients. METHODS: From 2004 to 2009, ten patients were pathologically diagnosed with sarcomatoid carcinoma of the gallbladder and underwent operation at our center. These characteristics, clinical presentations, tumor-node-metastasis (TNM) staging, surgical modes, and prognosis were reviewed, retrospectively. We collected the data of 46 patients reported in the English-language literature worldwide and analyzed the survival with ours. The survival rate was estimated using the Kaplan-Meier method, and was compared using the log-rank test. RESULTS: The median age of the 10 patients was 67 years (inter-quartile range 59-74 years), and the size of tumor inter-quartile ranged from 3.1 to 7.9 cm. In this series, 9 patients received radical surgery, and one undewent palliative surgery. There was no surgical mortality, and one patient underwent a second operation because of liver metastasis. The median survival time of the patients was 9 months (inter-quartile range 6-12 months), with 3 patients still being alive until follow-up; however, two patients had tumor recurrence. The data from the 56 patients (10 patients in our series and 46 reported elsewhere) statistically indicated that the median age was 66 years (inter-quartile range 61-74.5 years) and the overall median survival was 5.5 months (inter-quartile range 2.5-10 months). The survival time in the patients undergoing radical surgery (n=42) was significantly longer than that in the patients undergoing palliative surgery (n=14) (P=0.031). CONCLUSIONS: The survival of the patients with sarcomatoid carcinoma of the gallbladder is poor. Some patients may die

关键词： gallbladder neoplasm sarcomatoid carcinoma surgical therapy prognosis

Cytomegalovirus and chronic allograft rejection in liver transplantation

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World Journal of Gastroenterology 2004年第13期10卷 1857-1861页

作者： liang-HuiGao shu-Senzheng DepartmentofHapatobiliaryandPancreaticSurgery FirstAffiliatedHospitalZhejiangUniversityHangzhou310003ZhejiangProvinceChina

Cytomegalovirus (CMV) remains one of the most frequent viral infections and the most common cause of death after liver transplantation (LT). Chronic allograft liver rejection remains the major obstacle to long-term allograft survival and CMV infection is one of the suggested risk factors for chronic allograft rejection. The precise relationship between cytomegalovirus and chronic rejection remains *** review addresses the morbidity of cytomegalovirus infection and the risk factors associated with it, the relationship between cytomegalovirus and chronic allograft liver rejection and the potential mechanisms of it.

关键词：细胞肥大病毒 CMV 慢性同种异体移植物排斥反应肝脏移植传染病

Denitrification potential enhancement by addition of external carbon sources in a pre-denitrification process

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Journal of Environmental Sciences 2007年第3期19卷 284-289页

作者： PENG Yong-zhen MA Yong WANG shu-ying School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering Beijing University of Technology Beijing 100022 China

The aim of this study is to investigate the denitrification potential enhancement by addition of external carbon sources and to estimate the denitrification potential for the predenitrification system using nitrate utilization rate （NUR） batch tests. It is shown that the denitrification potential can be substantially increased with the addition of three external carbon sources, i.e. methanol, ethanol, and acetate, and the denitrification rates of ethanol, acetate, and methanol reached up to 9.6, 12, and 3.2 mgN/（g VSS.h）, respectively, while that of starch wastewater was only 0.74 mgN/（g VSS,h）. By comparison, ethanol was found to be the best external carbon source. NUR batch tests with starch wastewater and waste ethanol were carried out. The denitfification potential increased from 5.6 to 16.5 mg NO3-N/L owing to waste ethanol addition. By means of NUR tests, the wastewater characteristics and kinetic parameters can be estimated, which are used to determine the denitrification potential of wastewater, to calculate the denitrification potential of the plant and to predict the nitrate effluent quality, as well as provide information for developing carbon dosage control strategy.

关键词： predenitrification process external carbon addition ethanol denitrification potential

On-demand synthesis of high-quality,blue-light-active ZnSe colloidal quantum wires

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National Science Review 2022年第10期9卷 137-146页

作者： Yi Li Chong Zhang Jie Tian liang Wu Guo-Qiang Liu Hui-Hui Li Yu-Zhuo Zhang zhen-Chao Shao zhen He shu-Hong Yu Department of Chemistry Institute of Biomimetic Materials and Chemistry Anhui Engineering Laboratory of Biomimetic Materials Division of Nanomaterials and Chemistry Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of China Engineering and Materials Science Experiment Center University of Science and Technology of China

Beyond the state-of-the-art Cd-containing quantum wires(QWs),heavy-metal-free semiconductor QWs,such as ZnSe,are of great interest for next-generation environmental-benign ***,simultaneous,on-demand manipulation of their radial and axial sizes—that allows strong quantum confinement in the blue-light region—has so far been *** we present a two-step catalyzed growth strategy that enables independent,high-precision and wide-range controls over the diameter and length of ZnSe *** find that a new epitaxial orientation between the cubic-phase Ag2Se solid catalyst and wurtzite ZnSe QWs kinetically favors the formation of defect-free ultrathin *** to their high uniformity,the resulting blue-light-active,phase-pure ZnSe QWs exhibit well-defined excitonic absorption with the 1Se-1Shtransition linewidth as narrow as sub-13 *** the transient absorption spectroscopy,we further show that surface electron traps in these ZnSe QWs can be eliminated by thiol passivation,which results in long-lived charge carriers and high-efficiency solar-to-hydrogen conversion.

关键词： zinc selenide colloidal synthesis quantum wires heavy-metal-free solar conversion