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Debris flow susceptibility and propagation assessment in West koyulhisar, Turkey

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Journal of Mountain Science 2020年第11期17卷 2611-2623页

作者： Ali POLAT Dursun erİk Provincial Directorate of Disaster and Emergency Sivas 58050Turkey Republic of Turkey General Directorate of Highway 16.DistrictSivas 58049Turkey

Turkey is highly prone to landslides because of the geological and geographic *** study area,which is located in a tectonically active region,has been significantly affected by mass *** type landslides are frequently observed due to this *** study aims at determining the source area and propagation of debris flows in the study *** used the heuristic method to extract source areas of debris flow,and then used receiver operating characteristic(ROC)curve analysis to assess the performance of the method,and finally calculated the Area under curve(AUC)values being 83.64%and 80.39%for the success rate and prediction rate,*** calculated potential propagation area and runout distance with Flow-R *** conclusion,the obtained results(susceptibility map,propagation and runout distance)are very important for decisionmakers at the region located on an active fault zone,which is highly prone to natural *** outputs of this study could be used in site selection studies,designing erosion prevention systems and protecting existing human-made structures.

关键词： koyulhisar Debris flow Flow path assessment Heuristic method Landslide susceptibility mapping Geographical Information System(GIS)

Germination of Chenopodium Album in Response to Microwave Plasma Treatment

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Plasma Science and Technology 2008年第4期10卷 506-511页

作者： Bo■ena er Vitězslav STRA■k Michal er■ Milan TICH■ Petr paTEnkA Institute of Systems Biology and Ecology Academy of Sciences of the Czech RepublicNa Sádkách 7CZ-370 05eské BudějoviceCzech Republic University of South Bohemia in eské Budějovice Department of PhysicsJeronymova 10CZ-371 15 eské BudějoviceCzech Republic Charles University in Prague Faculty of Mathematics and PhysicsV Holeovikách 2CZ-180 00 Praha 8Czech Republic University of South Bohemia in eské Budějovice Department of PhysicsJeronymova 10 CZ-371 15 eské BudějoviceCzech Republic Technical University of LiberecDepartment of Material SciencesHáIkova 6CZ-461 17 Liberec iCzech Republic

The seeds of Lamb＇s Quarters （Chenopodium album agg.） were stimulated by low- pressure discharge. The tested seeds were exposed to plasma discharge for different time durations （from 6 minutes to 48 minutes）. Germination tests were performed under specified laboratory conditions during seven days in five identical and completely independent experiments. Significant differences between the control and plasma-treated seeds were observed. The treated seeds showed structural changes on the surface of the seat coat. They germinated faster and their sprout accretion on the first day of seed germination was longer. Germination rate for the untreated seeds was 15% while it increased approximately three times （max 55%） for seeds treated by plasma from 12 minutes to 48 minutes.

关键词： early growth germination Lamb's Quarters seed enhancement stimulation surfatron discharge

Effect of Different Surface Treatment Methods on the Friction and Wear Behavior of AISI 4140 Steel

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Journal of Materials Science & Technology 2010年第3期26卷 251-257页

作者： Mustafa Ulutan Osman n.Celik Hakan Gasan Umit er University of Eskisehir Osmangazi Faculty of EngineeringDepartment of Mechanical Engineering University of Eskisehir Osmangazi Institute of Metallurgy

In this study,the effects of various surface treatments on the friction and wear behavior of AISI 4140 steel have been *** surfaces of AISI 4140 steel were treated by quenching,carburizing,boronizing and plasma transferred arc （PTA） *** microstructural characteristics of surface treated steel samples were examined by optical microscopy and scanning electron microscopy （SEM）.The mechanical properties of the samples including the surface roughness,microhardness,and abrasive and adhesive wear characteristics were also *** tests were applied by using a block-on-disc configuration under dry sliding *** wear behavior and friction characteristics of the samples were determined as a function of sliding *** sample group was compared with the other sample groups,and it was observed that the carburized samples demonstrated the lowest weight losses;however,PTA-treated samples demonstrated the lowest coefficient of friction in comparison to the other sample groups at the same sliding distance.

关键词： AISI 4140 steel Quenching Boronizing Plasma transferred arc (PTA) Carburizing Sliding wear

一种基于柱面镜聚焦系统的高灵敏度全谱光谱仪

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光谱学与光谱分析 2025年第1期45卷 222-230页

作者：陈吉文陈作儿赵迎北方工业大学电气与控制工程学院北京100144

很多元素的最灵敏谱线主要分布在紫外波段。一些常被作为检测对象的重要元素,例如C、P和S,其谱线甚至位于200 nm以下的真空紫外波段。然而真空紫外波段内的辐射极易受空气吸收而无法在空气中传输。因此为了适用于紫外波段各谱线的检测,... 详细信息

很多元素的最灵敏谱线主要分布在紫外波段。一些常被作为检测对象的重要元素,例如C、P和S,其谱线甚至位于200 nm以下的真空紫外波段。然而真空紫外波段内的辐射极易受空气吸收而无法在空气中传输。因此为了适用于紫外波段各谱线的检测,常使用光程短、系统精简的罗兰圆光学系统作为光谱仪的色散系统,并且在进行检测分析时,还需对设备腔体内部建立相对真空的环境进行实验,进而减小实验环境对真空紫外波段内各谱线强度的削弱作用。然而即使在该条件下,P和S这两种元素在真空紫外波段的谱线灵敏度仍然较弱。为此为了实现真空紫外波段范围内的高灵敏度,本研究在距离像面前30 mm处位置设计了一个柱面镜聚焦系统。其采用了材料为CaF_(2)、中心厚度为5 mm以及弧矢面曲率半径为22.06 mm的柱面镜作为核心部件。并利用仿真软件Zemax对设计的光学系统进行仿真与优化,以及从非序列模式下的辐射照度仿真结果可知,柱面镜聚焦系统在几乎不影响分辨率的情况下对各波长成像灵敏度有较大的提升。最后以中低合金钢为检测样品,使用电火花激发光源对样品中各元素在紫外波段内的各谱线进行激发,进而验证光谱仪的各项性能:通过一次拟合、参比拟合以及二次拟合,建立每个元素谱峰强度和实际含量之间的数学模型,并算得各元素的拟合优度R^(2)均在0.99以上;柱面镜聚焦系统显著提高了设备在真空紫外波段的灵敏度,响应提高了1倍以上。实验结果表明,柱面镜聚焦系统的设计方法对于提升罗兰圆色散系统的灵敏度具有一定的参考价值。

关键词：紫外光谱罗兰圆光学系统柱面镜灵敏度拟合优度

siRnA therapeutics:a clinical reality

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Science China(Life Sciences) 2020年第4期63卷 485-500页

作者： Phei er Saw er-Wei Song Guangdong Provincial key Laboratory of Malignant Tumor Epigenetics and Gene Regulation Sun Yat-Sen Memorial HospitalSun Yat-Sen UniversityGuangzhou 510120China Breast Tumor Center Sun Yat-Sen Memorial HospitalSun Yat-Sen UniversityGuangzhou 510120China Zhongshan School of Medicine Breast SurgeryGuangzhou 510080China

Since the revolutionary discovery of RnA interference(RnAi),a remarkable progress has been achieved in understanding and harnessing gene silencing mechanism;especially in small interfering RnA(siRnA)*** its tremendous potential benefits,major challenges in most siRnA therapeutics remains unchanged-safe,efficient and target oriented delivery of *** years after the discovery of RnAi,siRnA therapeutics finally charts its way into *** we journey through the decades,we reminisce the history of siRnA discovery and its application in a myriad of disease ***,we highlight the breakthroughs in si RnA therapeutics,with special feature on the first FDA approved RnAi therapeutics Onpattro(patisiran)and the consideration of effective siRnA delivery system focusing on current siRnA nanocarrier in clinical ***,we present some challenges and multiple barriers that are yet to be fully overcome in siRnA therapeutics.

关键词： siRnA therapeutic disease treatment systemic siRnA delivery clinical application

Microstructure,Properties and Wear Behaviors of (ni_3Al)_p Reinforced Cu Matrix Composites

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Journal of Materials Science & Technology 2011年第10期27卷 937-943页

作者： Ibrahim elikyrek nese .krpe Tugba ler Remzi Grler Metallurgical and Materials Engineering Department Faculty of Engineering and ArchitectureEski sehir Osmangazi University Institute of Metallurgy Eski sehir Osmangazi University

Pure copper and its composites reinforced with ni3Al particles were produced by powder metallurgy （PM）. ni3Al powders were produced by mechanical ball milling from vacuum arc melted compounds. The ni3Al powders were characterized by X-ray diffraction （XRD）. The microscopy examinations revealed that the ni3Al particles were distributed uniformly in the matrix. The effects of the particle fraction on the density, electrical conductivity, strength and dry sliding wear resistance of composite were investigated. It was found that the density and electrical conductivity of the composites decrease while the compression yield strength and wear resistance of composites increase with an increase in the particle fraction. The dry sliding wear tests were performed with pin-on-disk geometry. After sliding wear tests, the worn surfaces were examined by scanning electron microscopy （SEM） equipped with an energy dispersive X-ray spectrometer （EDS）. Results have shown that the wear mechanism is oxidative and adhesive.

关键词： Metal matrix composites Powder metallurgy Wear Intermetallics

Phage display screening of therapeutic peptide for cancer targeting and therapy

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Protein & Cell 2019年第11期10卷 787-807页

作者： Phei er Saw er-Wei Song Guangdong Provincial key Laboratory of Malignant Tumor Epigenetics and Gene Regulation Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120China Breast Tumor Center Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120China

Recently,phage display technology has been announced as the recipient of nobel Prize in Chemistry *** display technique allows high affinity target-binding peptides to be selected from a complex mixture pool of billions of displayed peptides on phage in a combinatorial library and could be further enriched through the biopanning process;proving to be a powerful technique in the screening of peptide with high affinity and *** this review,we will first discuss the modifications in phage display techniques used to isolate various cancer-specific ligands by in situ,in vitro,in vivo,and ex vivo screening *** will then discuss prominent examples of solid tumor targeting-peptides;namely peptide targeting tumor vasculature,tumor microenvironment(TME)and overexpressed receptors on cancer cells identified through phage display *** will also discuss the current challenges and future outlook for targeting peptidebased therapeutics in the clinics.

关键词： phage display tumor targeting peptide,tumor vasculature tumor microenvironment tumor stromal cells over-expressed receptor

Simple Traits among Diaspore Weight/number,Plant Height and Ability of Vegetative Propagation

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Journal of Integrative Plant Biology 2008年第12期50卷 1563-1569页

作者： Bozena erá Institute of Systems Biology and Ecology Academy of Sciences of the Czech Republiceské Budějovice 37005

Several expected correlations among followed internal plant traits were confirmed using the dataset of 492 herbaceous species from the temporal zone of Central Europe. Average diaspore weight （seed mass）, reproductive capacity of population （number of produced diaspores）, species height, and ability of lateral spread were the plant traits considered. The evident correlations were confirmed among all investigated traits：（i） The reproductive capacity of population negatively correlated with diaspore weight, plant height, and vegetative propagation. The diaspore weight and their number are closely correlated and co-adapted. （ii） Bigger plant species produce bigger diaspores. These trends are obvious at the inter- and intra-family levels. （iii） Larger plant species showed higher ability to vegetative propagation.

关键词： comparison lateral spread reproduction seed production seed weight strategy trade-off.

Investigation of Microstructure, Microhardness and Thermal Properties of Ag-In Intermetallic Alloys Prepared by Vacuum Arc Meltings

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 182-187页

作者： ÇELİk erçevik ATA ESEner Pınar ÖZTÜRk Esra AkSÖZ Sezen nevşehir HacıBektaşVeli University Department of Physics50300NevşehirTurkey erciyes University Graduate School of Natural and Applied Sciences38039KayseriTurkey kocaeli University Department of Physics41380KocaeliTurkey

Ag-In intermetallic alloys were produced by using vacuum arc furnace. Differential Scanning Calorimetry(DSC) and Energy Dispersive X-Ray Spectrometry(EDX) were used to determine the thermal properties and chemical composition of the phases respectively. Microhardness values of Ag-In intermetallics were calculated with Vickers hardness measurement method. According to the experimental results, Ag-34 wt%In intermetallic system generated the best results of energy saving and storage compared to other intermetallic systems. Also from the microhardness results, it was observed that intermetallic alloys were harder than pure silver and Ag-26 wt%In system had the highest microhardness value with 143.45 kg/mm^(2).

关键词： thermal properties microstructure characterization microhardness alloys material characterization