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In-Situ Differentiation of Acidic and Non-Acidic Tundra via Portable X-ray Fluorescence (PXRF) Spectrometry

Pedosphere 2016年第4期26卷 549-560页

作者： Somsubhra CHAKRABORTY David C. WEINDORF GARY J. MICHAELSON chien lu ping Ashok CHOUDHURY Tarek KANDAKJI Autumn ACREE Akriti SHARMA WANG Dandan Uttar Banga Krishi Viswavidyalaya Cooch Behar 736165 Department of Plant and Soil Science Texas Tech University Lubbock TX 79409 University of Alaska Fairbanks Palmer Research Center Palmer AK 99645 Louisiana State University Agricultural Center Baton Rouge LA 70803 College of Geography and Remote Sensing Nanjing University of Information Science and Technology Nanjing 210044

Frozen soils or those with permafrost cover large areas of the earth's surface and support unique vegetative ecosystems. Plants growing in such harsh conditions have adapted to small niches, which allow them to survive. In northern Alaska, USA, both moist acidic and non-acidic tundra occur, yet determination of frozen soil p Hs currently requires thawing of the soil so that electrometric pH methods can be utilized. Contrariwise, a portable X-ray fluorescence(PXRF) spectrometer was used in this study to assess elemental abundances and relate those characteristics to soil pH through predictive multiple linear regressions. Two operational modes, Soil Mode and Geochem Mode, were utilized to scan frozen soils in-situ and under laboratory conditions, respectively, after soil samples were dried and ground. Results showed that lab scanning produced optimal results with adjusted coefficient of determination(R^2) of 0.88 and 0.33 and root mean squared errors(RMSEs) of 0.87 and 0.34 between elemental data and lab-determined pH for Soil Mode and Geochem Mode, respectively. Even though the presence of ice attenuated fluoresced radiation under field conditions, adjusted R^2 and RMSEs between the datasets still provided reasonable model generalization(e.g., 0.73 and 0.49 for field Geochem Mode). Principal component analysis qualitatively separated multiple sampling sites based on elemental data provided by PXRF, reflecting differences in the chemical composition of the soils studied. Summarily, PXRF can be used for in-situ determination of soil pH in arctic environments without the need for sample modification and thawing. Furthermore, use of PXRF for determination of soil pH may provide higher sample throughput than traditional eletrometric-based methods, while generating elemental data useful for the prediction of multiple soil parameters.

关键词： frozen soil Gelisols Geochem Mode proximal sensing Soil Mode soil pH determination

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Soil Pedon Carbon and Nitrogen Data for Alaska: An Analysis and Update

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Open Journal of Soil Science 2013年第2期3卷 132-142页

作者： Gary J. Michaelson chien-lu ping Mark Clark Agriculture and Forestry Experiment Station University of Alaska Fairbanks Palmer Research Center Palmer USA USDA- Natural Resources Conservation Service Palmer USA

We combined C and N related pedon data from the USDA-NRCS National Cooperative Soil Survey Soil Characterization Database with data from the University of Alaska Fairbanks (UAF) northern soils research program, representing 58 and 30 years of field work, respectively. Carbon and N data from 117 UAF pedons were added to 541 pedons from the USDA-NRCS data set for a total of 658. Missing carbon (C), nitrogen (N) and related data were added to nearly all of the USDA-NRCS Arctic region pedons from unpublished UAF data. We present relationships among soil parameters of the data set that are necessary for calculation of pedon soil organic C and N stores. These new relationships are necessary for better estimating missing soil bulk density (Db) from measured soil organic C by high-temperature combustion (SOCHTC) and for conversion of acid chromate reduction soil organic carbon (SOCACR) to SOCHTC. For the USDA-NRCS data, missing Db data were estimated and SOCACR corrected to SOCHTC using the new functional relationships developed. This allowed for pedon SOC and N stores to be calculated for 609 and 468 Alaska pedons respectively, the most available to-date. Additionally, functional relationships were developed for data within soil orders to estimate total SOCHTC and N stores in pedons with missing surface organic horizons where only thicknesses were known. These relationships are presented in order to fill-in missing data and to better define the existing data set for future use. Some 1904 missing Db data points and 1612 corrected SOCHTC data points were added to the total of 4240 points in the 609 pedons that constitute the updated dataset. When O-layer thickness functions developed here were used, SOC and N stores were calculated for an additional 137 and 184 pedons respectively.

关键词： Soil Carbon Soil Nitrogen Arctic Soils Pedotransfer Functions Permafrost Soils

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1991-2008年天山乌鲁木齐河源区多年冻土的变化

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冰川冻土 2010年第2期32卷 223-230页

作者：赵林刘广岳焦克勤李韧乔永平 chien-lu ping 中国科学院寒区旱区环境与工程研究所青藏高原冰冻圈观测研究站甘肃兰州730000 中国科学院寒区旱区环境与工程研究所冰冻圈科学国家重点实验室甘肃兰州730000 University of Alaska Fairbanks Fairbanks AlaskaUSA

天山乌鲁木齐河源多年冻土变化的研究,对于揭示气候变暖背景下,天山多年冻土对气候变化的响应以及由多年冻土变化引起的植被土壤演化、水文变化具有重要意义.对1991以来河源区海拔3500m左右的气温、降水、地温观测数据进行综合分析,结... 详细信息

天山乌鲁木齐河源多年冻土变化的研究,对于揭示气候变暖背景下,天山多年冻土对气候变化的响应以及由多年冻土变化引起的植被土壤演化、水文变化具有重要意义.对1991以来河源区海拔3500m左右的气温、降水、地温观测数据进行综合分析,结果表明:河源区的活动层呈逐渐增厚趋势,最大活动层厚度出现在2007年,达到1.60m,较1992年增加了0.35m;多年冻土活动层的变化与河源区夏半年(5-10月)的水热状况密切相关,活动层厚度随融化指数、夏半年降水量的增加而增大.多年冻土年变化深度由1993年的10m增加到12m左右;年平均地温上升明显,由1993年的-1.6℃上升到2008年的-1.0℃.年变化层以下的温度,均有不同程度的上升,年均增温速率随深度的增加而减小,推断长期持续的气候变暖是导致乌鲁木齐河源区多年冻土升温的主要驱动力.估算2008年的多年冻土下限深度约为86.8m,较1992年减小了7.7m,河源区多年冻土很可能正在发生自下而上的迅速退化.

关键词：天山乌鲁木齐河源多年冻土冻土变化

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Water budgets in an arid and alpine permafrost basin:Observations from the High Mountain Asia

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Advances in Climate Change Research 2024年第5期15卷 830-844页

作者： Qing-Feng WANG Hui-Jun JIN Dong-Liang luO Yu SHENG Jun WEN chien-lu ping Mark H.CLARK Qiang MA Xiao-Ying JIN Ji-Chun WU Yu-Zhong YANG Qiang LI Raul D.SERBAN Daqing YANG Victor F.BENSE Qing-Bai WU Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Qinghai-Beiluhe Plateau Frozen Soil Engineering Safety National Oseration and Research Station Norhwes Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou 730000China School of Civil Engineering and Transportation China-Russia Joint Laboratory of Cold Regions Engineering and Environmentand Permafrost InstituteNortheast Forestry UniversityHarbin 150040 China College of Atmospheric Science Plateau Atmosphere and Environment Key Laboratory of Sichuan ProvinceChengdu University of Information Technology Chengdu 610225China Agricultural and Forestry Experiment Station University of Alaska FairbanksPalmer Research CenterPalmer 99645USA USDA-Natural Resources Conservation Service Palmer 99645USA College of Water Conservancy and Hydropower Engineering Gansu Agricultural UniversityLanzhou 730070China Institute for Alpine Environment Eurac ResearchBolzano 39100Ilialy Faculty of Agricultural Environmental and Food SciencesFree University of Bozen-BolzanoBolzano 39100Italy Watershed Hydrology and Ecology Division Environment and Climate Change CanadaVictoria V8S 3V3Canada Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China Hydrology and Quantiative Water Management Group Department of Environmental SciencesWageningen UniversityWageningen 6700The Netherlands

Ground freeze-thaw processes have significant impacts on infiltration,runoff and ***,there are still critical knowledge gaps in understanding of hydrological processes in permafrost regions,especially of the interactions among permafrost,ecology,and *** this study,an alpine permafrost basin on the northeastern Qinghai-Tibet Plateau was selected to conduct hydrological and meteorological *** analyzed the annual variations in runoff,precipitation,evapotranspiration,and changes in water storage,as well as the mechanisms for runoff gen-eration in the basin from May 2014 to December *** annual flow curve in the basin exhibited peaks both in spring and autumn *** high ratio of evapotranspiration to annual precipitation(>1.O)in the investigated wetland is mainly due to the considerably underestimated‘observed'precipitation caused by the wind-induced instrumental error and the neglect of snow *** stream flow from early May to late October probably came from the lateral discharge of subsurface flow in alpine *** study can provide data support and validation for hydrological model simulation and prediction,as well as water resource assessment,in the upper Yellow River Basin,especially for the headwater *** results also provide case support for permafrost hydrology modeling in ungauged or poorly gauged watersheds in the High Mountain Asia.

关键词： Water budget Runoff Freeze-thaw processes Active layer Permafrost basin Alpine wetland

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Mesenteric ischemia with intrasplenic gas:A case report

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World Journal of Clinical Cases 2025年第7期13卷 52-56页

作者： Hsiang-Yu Tsang Chee-chien Yong Hao-ping Wang Department of Surgery Kaohsiung Chang Gung Memorial HospitalKaohsiung 833401Taiwan

BACKGROUND Acute mesenteric ischemia is a life-threatening *** gas is an extremely rare finding in such *** SUMMARY We report a case of a 79-year-old woman with a history of end-stage renal disease on hemodialysis for approximately 20 years,type 2 diabetes mellitus,and atrial fibrillation who presented with two days of epigastric pain.A computed tomography scan of the abdomen revealed intraperitoneal free air and significant intrasplenic *** revealed diffuse intestinal gangrene,and acute superior mesenteric ischemia was *** patient died within 24 hours owing to profound *** Intrasplenic gas is an extremely rare finding on computed tomography imaging in cases of acute mesenteric ischemia.

关键词： Acute mesenteric ischemia Spleen Hepatic portal venous gas Pneumatosis cystoides intestinalis Prognosis Case report

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Decomposition of formaldehyde by EPD photocatalyst filters in HVAC

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Particuology 2011年第5期9卷 497-501页

作者： chien-Chih Chen Ching-Song Jwo Tun-ping Teng Graduate Institute of Mechanical and Electrical Engineering National Taipei University of Technology Taipei. Taiwan China Department of Energy and Refrigerating Air Conditioning Engineering. National Taipei University of Technology Taipei Taiwan China Department of Industrial Education. National Taiwan Normal University Taipei Taiwan China

This study used electrophoretic deposition （EPD） to apply titanium oxide （TiO2） coating on stainless steel filters and investigated the effectiveness of photocatalytic oxidation of formaldehyde by TiO2 under various conditions of heating ventilation air conditioning （HVAC）. The results showed photocatalytic efficiency could reach 35,59% at 21 ℃ and 36.39% at 26℃ with 7 photocatalyst filters and 5 UVC lamps, the overall efficiency of formaldehyde removal of 52.37% at 21 ℃, and 56.8% at 26 ℃, By all experimental data can be found that the temperature for the photocatalytic performance is not obvious in the range of this study.

关键词： Electrophoretic deposition (EPD) TiO2 Filter HVAC

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Effects of solution treatment and cold rolling on structure and tensile properties of hot-rolled Ti-7.5Mo alloy

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Journal of Iron and Steel Research International 2019年第12期26卷 1366-1375页

作者： Yen-chun Chen chien-ping Ju Jiin-huey Chern Lin Department of Materials Science and Engineering ChengKung UniversityTaiwan 70101China

The effects of solution treatment(ST)and cold rolling(CR)on structure and tensile properties of a heavily hot-rolled(HR)Ti–7.5Mo alloy were *** results indicated that,after HR with a one-pass 65%reduction in thickness,the pores in as-received samples substantially disappeared,the misorientation angle distribution became broader,and grain texture shifted toward.Post-HR ST produced an orthorhombicα''-phase with fine needle-type morphology and caused misorientation to narrow down to 55°–65°with substantially random texture;post-ST CR caused misorientation shift toward high-angle side and texture towardand.With an increase in reduction in thickness,α'(102)intensity increased at the expense of two adjacent(112)/(022)α''-*** X-ray diffraction,metallography and electron backscattered diffraction on scanning electron microscope results indicated that pre-ST HR did not affect the formation of the desired low-modulusα''-phase when the alloy was subsequently *** a practical point of view,the most optimal tensile properties may be found in the sample solution-treated at 900°C for 30 min and cold-rolled by a 20%reduction in thickness,which demonstrated a yield strength of 924 MPa,an ultimate tensile strength of 933 MPa,a tensile modulus of 73 GPa,and an elongation of 26%.

关键词： Titanium alloy Ti–Mo alloy Electron backscattered diffraction Microstructure Mechanical property

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Instrumented Indentation Investigation on the Viscoelastic Properties of Porcine Cartilage

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Journal of Bionic Engineering 2013年第4期10卷 522-531页

作者： Yeau-Ren Jeng chien-ping Mao Kuan-Te Wu Department of Mechanical Engineering National Chung Cheng University Chia-Yi 621 Taiwan Advanced Institute for Manufacturing with High-tech Innovations National Chung Cheng University Chia-Yi 62102 Taiwan

Articular cartilage lubricates the contact surfaces in human joints and provides a shock-absorbing effect which protects the joint under dynamic loading. However, this shock-absorbing effect is gradually reduced as the result of normal wear, tear and aging-related cartilage loss. Thus, with the increasing average human life expectancy, the issue of joint health has attracted significant interest in recent decades. In developing new materials for the repair or regeneration of damaged articular cartilage, it is essential that the difference in the mechanical properties of healthy and damaged cartilages is well-understood. In the present study, the hardness and Young＇s modulus of damaged and healthy porcine articular cartilage samples are evaluated via a quasi-static nanoindentation technique. A dynamic mechanical analysis method is then applied to determine the viscoelastic properties of the two samples. The results presented in this study provide a useful insight into the mechanical properties of articular cartilage at the mesoscale, and therefore fill an important gap in the literature.

关键词： biotribology viscoelasticity human joints dynamic mechanical analysis depth-sensing technique

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Glucose detection in a highly scattering medium with diffuse photon-pair density wave

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Journal of Innovative Optical Health Sciences 2017年第1期10卷 53-58页

作者： Li-ping Yu Jheng-Syong Wu Sheng-Yi Chang chien Chou Biomedical Engineering Research Center Chang Gung University Taoyuan 333Taiwan Graduate Institute of Electro-Optical Engineering Chang Gung University Taoyuan 333Taiwan Institute of Chemistry A cademic SinicaNankangTaipei 115Taiwan Ph.D Program of Biomedical Engineering Chang Gung University Taoyuan 333Taiwan Department of Mechanics Ming Chi University of Technology New Taipei 243Taiwan

We propose a novel optical method for glucose measurement based on difuse photon-pair density wave(DPPDW)in a multiple scattering medium(MSM)where the light scattering of photon-pair is induced by refractive index mismatch between scatters and phantom ***-mentally,the DPPDW propagates in MSM via a two frequency laser(TFL)beam wherein highly correlated pairs of linear polarized photons are *** reduced scattering coefficientμ2s and absorption coefficientμ2a of DPPDW are measured simultaneously in terms of the amplitude and phase measurements of the detected heterodyne signal under arrangement at different dis-tances between the source and detection fibers in *** results show that the sensitivity of glucose detection via glucose-induced change of reduced scattering coefficient(δμ′2)is 0.049%mM^(-1)in a 1%intralipid *** addition,the linear range ofδμ′2s vs glucose concentration implies that this DPPDW method can be used to monitor glucose concentration continuously and noninvasively subcutaneously.

关键词： Difuse photon-pair density wave glucose multiple scattering polarization gating spatial coherence gating.

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Dense-Structured Network Based Bearing Remaining Useful Life Prediction System

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Computer Modeling in Engineering & Sciences 2022年第10期131卷 133-151页

作者： ping-Huan Kuo Ting-Chung Tseng Po-chien luan Her-Terng Yau Department of Mechanical Engineering National Chung Cheng UniversityChiayi62102Taiwan Advanced Institute of Manufacturing with High-Tech Innovations(AIM-HI) National Chung Cheng UniversityChiayi62102Taiwan

This work is focused on developing an effective method for bearing remaining useful life *** method is useful in accurately predicting the remaining useful life of bearings so that machine damage,production outage,and human accidents caused by unexpected bearing failure can be *** study uses the bearing dataset provided by FEMTO-ST Institute,Besancon,*** study starts with the exploration of neural networks,based on which the biaxial vibration signals are modeled and *** paper introduces pre-processing of bearing vibration signals,neural network model training and adjustment of training *** model is trained by optimizing model parameters and verifying its performance through *** proposed model’s superiority is also confirmed through a comparison with other *** this study,the neural network model is trained with various types of bearing data and can successfully predict the remaining useful *** algorithm proposed in this study achieves a prediction accuracy of coefficient of determination as high as 0.99.

关键词： Bearing neural network remaining useful life prediction machine learning

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