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All-Optical Format Conversion from RZ-DPSK to NRZ-DPSK at 40 Gbit/s

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Chinese Physics Letters 2011年第5期28卷 114-116页

作者： ZHANG Zheng PAN Di yu yu ZHANG Xin-liang Wuhan National Laboratory for Optoelectronics and College of Optoelectronic Science and Engineering Huazhong University of Science and TechnologyWuhan 430074

All-optical format conversion from return-to-zero differential phase shift keying(RZ-DPSK)to non-return-to-zero DPSK(NRZ-DPSK)is demonstrated by using a delay interferometer and a 1-nm-bandwidth filter at 40 Gbit/*** operation principle is theoretically analyzed and numerically simulated with the help of VPI Transmission Maker *** simulated results are in agreement well with the experimental *** conversion can be achieved with power penalty of 0.7dB.

关键词： Gbit/s DPSK interferometer

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浅析露天矿山生态修复地貌重塑成效评价方法

地下水 2024年第4期46卷 148-151页

作者：翟良良赵凯周小龙于天娇甘肃省地矿局第一地质矿产勘查院甘肃天水741020

露天矿山在开采过程中会破坏地形地貌景观及土地资源,形成大面积的裸露凹缺地貌,并改变原始地形。在采用合适的工程技术措施对矿山进行生态修复后,作为矿山生态修复成效评估的一项重要内容,需对矿山的地貌重塑效果进行评价。本研究选取... 详细信息

露天矿山在开采过程中会破坏地形地貌景观及土地资源,形成大面积的裸露凹缺地貌,并改变原始地形。在采用合适的工程技术措施对矿山进行生态修复后,作为矿山生态修复成效评估的一项重要内容,需对矿山的地貌重塑效果进行评价。本研究选取地貌因子中的坡向、坡度、地形起伏度及高程变异系作为地貌重塑评价指标,通过横向对比分析生态修复区与周边区地形地貌的协调性,及纵向对比生态修复区在修复前后的地形起伏,给出了每个指标的赋分标准及权重、地貌重塑综合赋分方法及分级,以供参考利用。文中以2处历史遗留矿山/取土点为例,利用ARCGIS计算了相关评价指标值,综合赋分结果为2处矿点/取土点的生态修复区的地貌重塑效果好,与实际调查结果一致,经检验该评价方法可行。

关键词：地貌重塑地形地貌协调性 ARCGIS 生态修复加权指数和

Protic ionic liquid-promoted synthesis of dimethyl carbonate from ethylene carbonate and methanol

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Chinese Chemical Letters 2020年第3期31卷 667-672页

作者： yu Song Xing He Bing yu Hong-Ru Li liang-Nian He State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China College of Chemistry and Molecular Engineering Zhengzhou UniversityZhengzhou 450001China College of Pharmacy Nankai UniversityTianjin 300353China

In this work,the protic ionic liquid[DBUH][Im](1,8-diazabicyclo[5.4.0]-7-undeceniumimidazolide)was developed as an efficient catalyst for the transesterification of ethylene carbonate with methanol to produce dimethyl *** 70℃,up to 97%conversion of ethylene carbonate and 91%yield of dimethyl ca rbonate were obtained with 1 mol%[DBUH][Im](relative to ethylene carbonate)as catalyst in 2 *** at room temperature,the conversion of ethylene carbonate can reach 94%and the yield of dimethyl carbonate can approach 81%for 6 *** mechanism investigation showed the high catalytic efficiency of this ionic liquid results from the synergistic activation effect,wherein the cation can activate ethylene carbonate and the anion can activate methanol through hydrogen bond formatio *** the reusability of the ionic liquid need to be further improved,high efficiency and comme rcial availability of[DBUH][Im]render it a promising catalyst for the preparation of dimethyl carbonate.

关键词： Dimethyl carbonate Transesterification Protic ionic liquid Synergistic effect Sustainable chemistry

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不同方法治疗疤痕临床效果分析

实用医院临床杂志 2008年第3期5卷 77-77页

作者：敬梁渝王艺颖攀钢集团成都医院烧伤整形科四川成都610051

目的探讨各种疤痕的有效治疗方法。方法回顾性分析215例疤痕的诊治和转归情况。结果随访半年至4年,治愈184例,显效22例,无效9例。结论疤痕应及早治疗,不同疤痕应采用不同方法治疗。

关键词：疤痕治疗转归

Evolutionary trend of water cycle in Beichuan River Basin of China under the influence of vegetation restoration

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Journal of Groundwater Science and Engineering 2021年第3期9卷 202-211页

作者： liang Zhu jing-tao Liu Ming-nan Yang yu-xi Zhang De-ping Wen Institute ofHydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China. Key Laboratory of Groundwater Contamination and Remediation China Geological Survey&Ilebel ProvinceShijiazhuang 050061China. Qinghai Provincial Flood and Drought Disaster Prevention Service Center Xining 810001China.

The study aims to identify a suitable site for open and bore well in a farmhouseusing ground magnetic survey in south *** also aims to define depth to granitoid and structural elements which traverse the selected *** data(n=84)measured,processed and interpreted as qualitative and *** results of total magnetic intensities indicate that the area is composed of linear magnetic lows trending NE-SW direction and circular to semi-circular causative *** magnetic values ranged from-137 nT to 2345 nT with a mean of 465 *** to equator shows significant shifting of causative bodies in the southern and northern *** signal map shows exact boundary of granitic *** directional filter has brought out structural element trending NE-SW *** of individual profile brought to light structurally weak zone between 90 m and 100 m in all the profile *** decrease of magnetic values from 2042 nT to 126 nT noticed in profile line 6 between 20 m and 30 m indicates fault *** breaks obtained from these maps were visualized,interpreted and identified two suitable sites for open and bore *** averaged power spectrum estimates depth of shallow and deep sources in 5 m and 50 m,*** method has also been applied to estimate depth of granitoid and structural elements using structural indexes 0,1,2,and 3 and found depth ranges from90 *** indicates magnetic method is one of the geophysical methods suitable for groundwater exploration and site selection for open and borewells.

关键词： Vegetation coverage Water cycle in a river basin Ecological water consumption Water conservation

Review of vanadium-based oxide cathodes as aqueous zinc-ion batteries

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Rare Metals 2023年第9期42卷 2868-2905页

作者： Min Chen Shu-Chao Zhang Zheng-Guang Zou Sheng-Lin Zhong Wen-Qin Ling jing Geng Fang-An liang Xiao-Xiao Peng Yang Gao Fa-Gang yu College of Materials Science and Engineering Guilin University of TechnologyGuilin541004China

Research on energy storage technology is a vital part of realizing the dual-carbon strategy at this *** zinc-ion batteries(AZIBs)are favorable competitors in various energy storage devices due to their high energy density,reassuring intrinsic safety,and unique cost *** design of cathode materials is crucial for the large-scale development and application of ***-based oxides with high theoretical capacity,diverse valence states,as well as high electrochemical activity,have been widely used as cathode materials for ***,there are some obstacles,including low electronic conductivity and sluggish kinetics,hindering their further application in *** view of the above,this review will introduce a series of modification methods including morphology design,defect engineering,ingenious combination with conductive materials,and modification of electrolyte and zinc anode according to the intrinsic disadvantage of vanadium oxides and summarize the research progress of various modification methods including zinc storage performance and ***,several reasonable prospects will be proposed to appease the needs of basic research and practical applications according to the current status.

关键词： Aqueous zinc-ion batteries(AZIBs) Vanadium-based oxides Preparation Modification strategy Mechanism

South-north asymmetry of proton density distribution in the Martian magnetosheath

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Earth and Planetary Physics 2020年第1期4卷 32-37页

作者： jing Wang XiaoJun Xu Jiang yu yuDong Ye State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao 999078China School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai Guangdong 519082China

We perform a statistical analysis of data from the Mars Atmosphere and Volatile Evolution (MAVEN) project on the global distribution of protons in the Martian magnetosheath. Our results show that the proton number density distribution has a south-north asymmetry. This south-north asymmetry is most likely caused by the south-north asymmetric distributions of the crustal magnetic fields at Mars. The strong crustal magnetic fields push the inner boundary of magnetosheath to a higher altitude in the southern hemisphere. Due to the outward movement of the inner boundary of the magnetosheath, a compressed magnetosheath forms, causing subsequent increases in proton number density, thermal pressure, and total pressure. Eventually, a balance is reached between the increased total pressure inside the magnetosheath and the increased magnetic pressure inside the induced magnetosphere. Our statistical study suggests that the Martian crustal magnetic fields can strongly affect the proton number density distribution in the Martian magnetosheath.

关键词： Martian magnetosheath south-north asymmetry proton density distribution crustal magnetic field

An Improved DV-Hop Localization Algorithm Based on Selected Anchors

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Computers, Materials & Continua 2020年第10期65卷 977-991页

作者： jing Wang Anqi Hou yuanfei Tu Hong yu Department of Computer Science and Technology Nanjing Tech UniversityNanjing211800China Department of Engineering Technology Fitchburg State UniversityFitchburgMA 01420USA

Wireless Sensor Network(WSN)based applications has been extraordinarily helpful in monitoring interested *** information of surrounding environment with meaningful geometric information is *** to design the localization algorithm that can effectively extract unknown node position has been a challenge in *** all localization technologies,the Distance Vector-Hop(DV-Hop)algorithm has been most popular because it simply utilizes the hop counts as connectivity *** paper proposes an improved DV-Hop based algorithm,a centroid DV-hop localization with selected anchors and inverse distance weighting schemes(SIC-DV-Hop).We adopt an inverse distance weighting method for average distance amelioration to improve *** in this paper,we propose an inclusive checking rule to select proper anchors to avoid the inconsistency existing in centroid localization ***,an improved multilateration centroid method is presented for the *** are conducted on two different network topologies and experiments results show that compared with existing DV-Hop based algorithms,our algorithm can significantly improve the performance meanwhile cost less network resource.

关键词： DV-Hop selective mechanism centroid estimation

Cr胁迫对‘中山杉406’幼苗生长和生理生化特性的影响

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植物资源与环境学报 2024年第5期33卷 22-32页

作者：胡加玲於朝广梁文超王晓容谢寅峰南京林业大学生命科学学院南方现代林业协同创新中心江苏南京210037 北京市城市河湖管理处北京100144 江苏省中国科学院植物研究所(南京中山植物园)江苏省植物资源研究与利用重点实验室江苏南京210014 重庆市南山植物园管理处重庆400065

采用水培法模拟实验,以亲本落羽杉〔Taxodium distichum(Linn.)Rich.〕为对照,比较了不同浓度和处理时间Cr胁迫对‘中山杉406’(‘Zhongshanshan 406’)幼苗生长、抗氧化系统和光合系统的影响。结果显示:在中浓度(5.00μmol·L^(-1))和... 详细信息

采用水培法模拟实验,以亲本落羽杉〔Taxodium distichum(Linn.)Rich.〕为对照,比较了不同浓度和处理时间Cr胁迫对‘中山杉406’(‘Zhongshanshan 406’)幼苗生长、抗氧化系统和光合系统的影响。结果显示:在中浓度(5.00μmol·L^(-1))和高浓度(20.00μmol·L^(-1))Cr处理28 d时,‘中山杉406’幼苗的相对生长速率和相对含水率以及叶片的相对电导率、叶绿素含量和丙二醛(MDA)含量的变幅均小于落羽杉。随着Cr浓度的增加和处理时间的延长,‘中山杉406’幼苗叶片的超氧化物歧化酶(SOD)和过氧化物酶(POD)活性总体呈升高的趋势,而落羽杉幼苗叶片的SOD和POD活性总体呈先升高后降低的趋势,‘中山杉406’在处理后期(28 d)能维持较高的抗氧化酶活性。与对照(0.00μmol·L^(-1)Cr)相比,在1.25和5.00μmol·L^(-1)Cr处理下,‘中山杉406’幼苗叶片的PSⅡ最大光化学效率(F_(v)/F_(m))、PSⅡ有效光化学效率(F_(v)′/F_(m)′)和PSⅡ实际光化学效率(Φ_(PSⅡ))总体变化不大,而落羽杉的这3个叶绿素荧光参数在5.00μmol·L^(-1)Cr处理下显著降低,且在20.00μmol·L^(-1)Cr处理28 d时的降幅明显大于‘中山杉406’;随着处理时间的延长,‘中山杉406’幼苗叶片非光化学猝灭系数(NPQ)总体呈升高的趋势,而落羽杉从处理14 d开始变化不大。Cr胁迫下2种植物相对生长速率与叶片的光合系统指标(叶绿素含量、F_(v)/F_(m)值、F_(v)′/F_(m)′值、Φ_(PSⅡ)值)以及抗氧化系统指标(SOD活性、POD活性和MDA含量)有较高关联度,Φ_(PSⅡ)值和叶绿素含量与抗氧化系统指标间有较强关联性。综上所述,‘中山杉406’和落羽杉对低浓度(1.25μmol·L^(-1))Cr胁迫有一定的生长适应性,‘中山杉406’对中、高浓度Cr胁迫的抗性更强。Cr胁迫下较强的PSⅡ光化学性能、抗氧化能力和PSⅡ热耗散能力是‘中山杉406’维持较高生长速率以及防御光抑制和光破坏的重要机制。

关键词： Cr胁迫 ‘中山杉406’ 落羽杉生长抗氧化系统光合系统