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Simulating hydrological responses to climate change using dynamic and statistical downscaling methods: a case study in the Kaidu River basin, Xinjiang, China

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Journal of Arid Land 2018年第6期10卷 905-920页

作者： ba Wulong DU Pengfei LIU Tie baO Anming LUO min mujtaba HASSAN QIN Chengxin State Key Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua University Beijing 100084China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Department of Space Sciences Institute of Space TechnologyIslamabad 44000Pakistan

Climate change may affect water resources by altering various processes in natural ecosystems. Dynamic and statistical downscaling methods are commonly used to assess the impacts of climate change on water resources. Objectively, both methods have their own advantages and disadvantages. In the present study, we assessed the impacts of climate change on water resources during the future periods (2020–2029 and 2040–2049) in the upper reaches of the Kaidu River basin, Xinjiang, China, and discussed the uncertainties in the research processes by integrating dynamic and statistical downscaling methods (regional climate models (RCms) and general circulation modes (GCms)) and utilizing these outputs. The reference period for this study is 1990–1999. The climate change trend is represented by three bias-corrected RCms (i.e., Hadley Centre Global Environmental model version 3 regional climate model (HadGEm3-ra), Regional Climate model version 4 (RegCm4), and Seoul National University meso-scale model version 5 (SUN-mm5)) and an ensemble of GCms on the basis of delta change method under two future scenarios (RCP4.5 and RCP8.5). We applied the hydrological SWAT (Soil and Water Assessment Tool) model which uses the RCms/GCms outputs as input to analyze the impacts of climate change on the stream flow and peak flow of the upper reaches of the Kaidu River basin. The simulation of climate factors under future scenarios indicates that both temperature and precipitation in the study area will increase in the future compared with the reference period, with the largest increase of annual mean temperature and largest percentage increase of mean annual precipitation being of 2.4°C and 38.4%, respectively. based on the results from bias correction of climate model outputs, we conclude that the accuracy of RCm (regional climate model) simulation is much better for temperature than for precipitation. The percentage increase in precipitation simulated by the three RCms is generally higher t

关键词： RCm GCm climate change downscaling bias correction SWAT Tianshan mountains

A comparison research on replacements of ba^(2+)by Lu^(3+)and ba^(2+)-Si^(4+)by Lu^(3+)-Al^(3+)in baSi_(2)O_(2)N_(2):Eu phosphors

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Journal of rare Earths 2022年第1期40卷 20-28页

作者： di Wu Lili Liu Huangbin Duan Junrong Wang Wanfang Zou Jiaqing Peng Xinyu Ye Faculty of materials metallurgy and Chemistry Jiangxi University of Science and TechnologyCanzhou 341000China National Engineering Research Center for Ionic rare Earth Ganzhou 341000China Key Laboratory of rare Earth Luminescence materials and Devices of Jiangxi Province Ganzhou 341000China Jiangxi rare Earth Functional materials Technology Co. Ltd.Ganzhou 341000.China

As a cyan-emitting oxonitridosilicate phosphor,baSi_(2)O_(2)N_(2):Eu^(2+)can be used as a competent cyan compensator to improve the color rendering index of white light-emitting diodes(WLEDs).However,low luminescence efficiency and poor thermal stability of this type of phosphor seriously suppress its actual application in full-spectrum *** replacements of ba^(2+)by Lu^(3+)and ba^(2+)-Si^(4+)by Lu^(3+)-Al^(3+)can greatly increase the luminescence intensity and improve the thermal stability at the same *** Lu^(3+)doping,the internal quantum efficiencyηIQE ba_(0.925)Si_(2)O_(2)N_(2):0.03 Eu^(2+),0.045 Lu^(3+)is 24.08%higher than that of ba_(0.97)Si_(2)O_(2)N_(2):0.03 Eu^(2+).After Al^(3+)co-doping,theηIQE is further increased by 10.31%compared to ba_(0.925)Si_(2)O_(2)N_(2):0.03 Eu^(2+),0.045 Lu^(3+).When the temperature rises to 473 K,the luminescence intensity of ba_(0.925)Si_(2)O_(2)N_(2):0.03 Eu^(2+),0.045 Lu^(3+)maintains 62.32%of that at room temperature,which increases by 17.35%in relative to the ba_(0.97)Si_(2)O_(2)N_(2):0.03 Eu^(2+),while the luminescence intensity of ba_(0.925)Si_(1.97)O_(2)N_(2):0.03 Eu^(2+),0.045 Lu^(3+),0.03 Al^(3+)keeps 73.87%of the initial value,which increases by18.52%compared to ba_(0.925)Si_(2)O_(2)N_(2):0.03 Eu^(2+),0.045 Lu^(3+).The mechanisms for luminescence and thermal stability improvement are *** ba_(0.925)Si_(1.97)O_(2)N_(2):0.03 Eu^(2+),0.045 Lu^(3+),0.03 Al^(3+)cyan phosphor,Y3 Al5 O12:Ce3+yellow phosphor and CaAlSiN3:Eu^(2+)red phosphor are mixed thoroughly and coated on a blue LED(450 nm)to assemble a *** WLED demonstrates a color rendering index(ra)of 97.1 at150 mA,and the R1-R15 values are all above *** results indicate that as an effective cyan compensator in WLED,the baSi_(2)O_(2)N_(2):Eu^(2+),Lu^(3+),Al^(3+)phosphor has great application prospect in the field of full-spectrum lighting.

关键词： Full-spectrum lighting baSi_(2)O_(2)N_(2) Luminescence efficiency Thermal stability rare earths

Optimisation of pulsed laser deposited ba_(1-x)K_(x)BiO_(3)thin films with tunable superconducting properties by control of K doping level,x

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Superconductivity 2024年第3期11卷 66-72页

作者： A.Kursumovic J.Prestigiacomo m.de h-Óra W.Li J.Feighan V.Smolyaninova I.Smolyaninov m.Osofsky J.L.macmanus-Driscoll Department of materials Science and metallurgy University of CambridgeCB3 OFS CambridgeUnited Kingdom Department of Physics Astronomy and Geosciences Towson University 8000 York Rd.TowsonMD 21252USA materials Science and Technology division Naval Research LaboratoryWashington DC20375USA Saltenna LLC 1751 Pinnacle Dr.Ste.600McLeanVA 22102-4007 USA

The mid-T_(C) superconductor ba1-XKXBiO3(BKBO)exhibits different superconducting mechanisms depending on x,in the range∼0.35–*** optimal doping for the highest T_(C) is reported to be around x=*** understand more about the dependence of the superconducting mechanism on x,high quality and reproducible epitaxial films with controlled x are *** has been challenging owing to the volatility of K and(to a lesser extent)*** this work,we use pulsed laser deposition(PLD)with several novel process steps to achieve high-quality films in a reproducible *** include a modified method for target preparation,a low NO_(2) growth pressure,and precise positioning of substrates in the PLD *** T_(C) films(32 K onset)were grown from an x=0.4 target,*** no excess K,as is normally ***,higher K content films(made from an x=0.45 target),were also *** x=0.45 films had a lower T_(C) (22.5 K onset),as expected for(K)overdoped films,with very high upper critical field,H_(C2) (0 K),and irreversibility field,Hirr(0 K),values,from linear extrapolation,of∼31.7 T and∼28.8 T,*** growth methodology demonstrated in this work is highly beneficial for fundamental mechanistic studies of this complex superconductor on which there is renewed interest,and where controlled compositions and crystalline quality are currently limited.

关键词： doping superconductor superconducting

用于砂浆保护层腐蚀风险评估的宏电池电流监测

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功能材料 2010年第A2期41卷 235-238,242页

作者：卢爽巴恒静哈尔滨工业大学土木工程学院黑龙江哈尔滨150060

开发了一种可埋置在砂浆内部的宏电池电流传感器。对传感器的阴极与阳极电位,电极间的砂浆电阻以及宏电池电流进行了监测。并针对阳极的不同腐蚀状态,对宏电池电流发生的电化学本质进行了探讨。结果表明,宏电池电流的大小与砂浆电阻、... 详细信息

开发了一种可埋置在砂浆内部的宏电池电流传感器。对传感器的阴极与阳极电位,电极间的砂浆电阻以及宏电池电流进行了监测。并针对阳极的不同腐蚀状态,对宏电池电流发生的电化学本质进行了探讨。结果表明,宏电池电流的大小与砂浆电阻、阴极与阳极电位以及阴极阳极的极化电阻之间有直接关系。在阳极处于钝化状态时,宏电池电流几乎可以忽略,这取决于微弱的腐蚀驱动力、较高的电极极化电阻和砂浆电阻。而阳极处于活化状态时,宏电池电流显著增大,此时的腐蚀驱动力较大,而砂浆电阻较小。此外,在活化状态下通过对宏电池电流电化学本质的分析确定了阳极的ln(Ia·Ic)的值,对砂浆保护层的服役状态和钢筋的腐蚀情况进行了评估。试验结果显示,开发的宏电池电流传感器为钢筋混凝土结构的腐蚀状态进行长期的预警和系统的评价提供新的途径。

关键词：宏电池传感器电阻腐蚀砂浆

Comparison of One-Step and multistep Polishing Systems for the Surface Roughness of Resin Composites

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Open Journal of Stomatology 2016年第3期6卷 73-80页

作者： Ismail Hakkı baltacıoğlu Ozgur Irmak Nuran Ulusoy Esra Cengiz Yıldırım Hakan bağış Department of Restorative Dentistry Faculty of Dentistry Ankara University Ankara Turkey Department of Restorative Dentistry Faculty of Dentistry Osmangazi University Eskisehir Turkey Department of Restorative Dentistry Faculty of Dentistry Near East University Mersin Turkey

Aim: This study analyzed the effect of different finishing and polishing systems on the surface roughness of a microfilled (Amaris), and a nanofilled resin composite (Clearfil majesty Esthetic) using Scanning electron microscope (SEm) analysis and surface roughness tester. materials and methods: Thirty five specimens of each material were prepared in a plexiglass mold (10 mm in diameter and 2 mm in depth) and cured against a mylar matrix strip to create a baseline surface. The average surface roughness was measured using a surface profilometer (mahr Perthometer SP4, Germany) in three different positions on each sample before and after finishing with one of the seven finishing procedures: Procedure 1: mylar strip (control), Procedure 2: Tungsten carbide burs, Procedure 3: diamond burs, Procedure 4: Procedure 2 + one-step diamond micropolisher (PoGo), Procedure 5: Procedure 2 + multi-step discs (Super-snap), Procedure 6: Procedure 3 + one-step diamond micropolisher (PoGo), Procedure 7: Procedure 3 + multi-step discs (Super-snap). The obtained data were analyzed using two-way analysis of variance (ANOVA) and Duncan test at a p = 0.05 significance level. Results: Nanofilled composite showed significantly lower ra values than microfilled composite in procedures 4, 6 and 7 (p 0.05). Conclusion: Nanofilled resin composite showed significantly lower ra values than microfilled resin composite. Regardless of finishing methods, diamond micro-polisher produced smoother surfaces than polishing discs.

关键词： Surface Roughness Resin Composites One-Step Polishing

Natural radioactivity measurement and Dose Assessment in Soil Samples from Some Selected Areas of mali

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World Journal of Nuclear Science and Technology 2019年第2期9卷 67-73页

作者： Issiaka Traoré Abdramane ba Abdel mjid Nourreddine Département de Physique Université des Sciences des Techniques et Technologies de Bamako Bamako Mali Institut Pluridisciplinaire Hubert Curien (IPHC) Université de Strasbourg Strasbourg France

This is the first time that a study applies the gamma ray spectroscopy using a high purity germanium to evaluate the terrestrial gamma radiation level by detector in selected regions of mali. The results reveal that the activity concentrations of naturally occurring 226ra, 232Th and 40K radionuclides ranges between respectively 17.26 ±1.81 and 105.43 ±10.36;20.41 ±2.52 and 180.85 ±19.69;41.33 ±8.26 and 627.63 ±85.62 Bq⋅kg−1. The measures of radium equivalent activity (raeq), absorbed dose rates (ADR), annual effective dose rate (AEDR), external hazard index (Hex), internal hazard index (Hin) and excess lifetime cancer risk (ELCR) were evaluated. Some of the obtained values exceed the recommended safe levels. Further studies are necessary to constitute a baseline reference data about the terrestrial radiation in mali.

关键词： Soil radioactivity radiological Hazard Population Exposure Gamma Spectrometry mali

CT Scans and Delays in diagnosis of Stroke in Senegal’s Regional Hospitals: A multicenter Study of 655 Cases

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Open Journal of medical Imaging 2020年第2期10卷 96-104页

作者： Hamidou Deme Nfally badji Léra Géraud Akpo Oumou dieng Abdoulaye dione diop Fallou Galass Niang mouhamadou Hamine Toure Ibrahima Faye malick diouf Aicha Ndichout marie mbengue Cherif mohamadou Aidara mamadou Ly Ousmane Sano Ndiaga matar Gaye Ousmane Cissé Abdoulaye Ndoye diop Aissata Ly ba Sokhna ba diop El Hadj Niang radiology Department of the Aristide Le Dantec Hospital in Dakar Dakar Senegal radiology Department of the CHNU de Fann in Dakar Dakar Senegal Neurology Department of the Fann University Hospital in Dakar Dakar Senegal radiology Department of the Albert Royer Children’s Hospital of Fann in Dakar Dakar Senegal

Stroke represents the 2nd cause of mortality and 1st cause of physical disability in the adult population. In Senegal, it represents 30% of hospitalization and 2/3 of the mortality in the department of neurology in the capital city, Dakar. Objective: To specify the types of stroke and to evaluate diagnostic delays in Senegal’s regional hospitals. materials and methods: This was a retrospective, cross-sectional, descriptive, multicentric study for 4 years (from 2014 to 2017) including any patient presenting a clinical suspicion with a CT scan confirmation of stroke in one of the 9 regional hospitals in Senegal with a recruitment period of 6 months per hospital. CT scans were performed with a 16 slices machine in 6 hospitals, 4 slices in 2 hospitals and 2 slices in 1 hospital. We studied the types and location of strokes, the associated signs and the time from stroke onset to admission and the time from admission to CT scan. Results: 655 patients were retained including 322 men and 333 women for an m/F ratio of 0.96. The average age was 63 years (range: 7 years, 112 years). High blood pressure was noted in 59.2% of patients and diabetes in 10.7% of patients. Strokes were ischemic in 76% of cases involving the middle cerebral artery in 73% of cases and hemorrhagic in 24%, of which 80.7% were deep localized. A mass effect was noted in 7.5% of cases, an engagement in 6.9% of cases and ventricular hemorrhage in 2.7% of cases. The delay between the onset of the deficit and admission was less than 6 hours in 10.6% of patients. The time between the onset of stroke and admission to hospital was specified in 416 patients (63.5%) of the study population, it was less than 6 hours in 10.6% of patients, between 6 hours and 24 hours for 29.3% and more than 24 hours for 60.1%. Between admission and the CT scan, the time was precise in 459 patients (70%), it was less than 6 hours in 37.9%, between 6 hours and 24 hours in 43.6 % and more than

关键词： Stroke CT Scans diagnostic Delays

Duplication of the Inferior Vena Cava, Azygos Continuation and Retro Aortic Renal Vein: Fortuitous discovery

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Forensic medicine and Anatomy Research 2021年第3期9卷 31-40页

作者： Géraud Léra Akpo Ndeye Bigué mar Soukeyna Abouabdillah Nfaly badji Hamidou Deme Youssoupha Kasse Ibrahima Niang mamadou Lamine Gueye marcel mbarga Ibrahima Faye Abdoulaye dione diop Assane Ndiaye Sokhna ba diop El Hadji Niang Service de radiologie Imagerie Médicale de l’h&#244pital Ariste Le Dantec Dakar Sénégal Laboratoire d’Anatomie UFR des Sciences de la Santé Université Iba Der Thiam de Thiès Thiès Sénégal Service de radiologie Imagerie Médicale de l’h&#244pital Fann Dakar Sénégal Service de radiologie Imagerie Médicale de l’h&#244pital Dalal Jam Dakar Sénégal Laboratoire d’Anatomie UFR des Sciences de la Santé Université Assane SECK de Ziguinchor Ziguinchor Sénégal

We present a rare case associating inferior vena cava’s (IVC) complex variations. Anatomical, embryological and clinical aspects are discussed. Duplication’s discovery was fortuitous during an abdominal ultrasound and was confirmed by the CT scan. The latter also highlighted azygos continuation, retro aortic renal vein and an iliac venous anomaly. These variants are important to know in order to be able to differentiate them from lymphadenopathy, para-vertebral masses, and aortic pathologies. It is necessary to report them before any retroperitoneal surgery or interventional vascular procedure.

关键词： Duplication IVC Continuation Azygos Tomodensitometry

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基于多尺度融合的深度人群计数算法

激光与光电子学进展 2020年第24期57卷 307-315页

作者：左静巴玉林兰州交通大学自动化与电气工程学院甘肃兰州730070

在人群计数统计时存在相机透视、人群重叠、人群遮挡等众多干扰因素,使人群计数的准确性不高。针对这一问题,提出一种多尺度融合的深度人群计数算法。首先,利用VGG-16网络的部分结构提取出人群底层特征信息;其次,以膨胀卷积理论为基础,... 详细信息

在人群计数统计时存在相机透视、人群重叠、人群遮挡等众多干扰因素,使人群计数的准确性不高。针对这一问题,提出一种多尺度融合的深度人群计数算法。首先,利用VGG-16网络的部分结构提取出人群底层特征信息;其次,以膨胀卷积理论为基础,构建多尺度特征提取模块,实现多尺度上下文特征信息的提取,降低模型参数量;最后通过将底层细节特征信息和高层语义特征信息融合的方式,提升模型计数性能和密度图质量。在三个公开数据集上对不同算法进行测试。实验结果表明,与其他人群计数算法相比,所提算法的平均绝对误差和方均误差均有不同程度的降低,说明所提算法具有较好的准确性、鲁棒性及良好的泛化性。

关键词：机器视觉人群计数密度图卷积神经网络膨胀卷积特征融合