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springs Emerging along the Elevation Gradient Indicate Intensive Groundwater-Surface Water Exchange in an Alpine Headwater Catchment, Northwestern China

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Journal of Earth Science 2023年第1期34卷 181-193页

作者： Yalu Hu Ziyong Sun Rui Ma School of Environmental Studies China University of GeosciencesWuhan430078China Laboratory of Basin Hydrology and Wetland Eco-Restoration China University of GeosciencesWuhan430078China State Environmental Protection Key Laboratory of Source Apportionment and Control of Aquatic Pollution Ministry of Ecology and EnvironmentWuhan430078China Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science China University of GeosciencesWuhan430078China

Groundwater plays an important role in sustaining the streamflow in cold alpine area, but is poorly understood due to a lack of direct access. About 98 groups of springs are observed at the upper reaches of Heihe River Basin, which provide an opportunity to explore the main aquifers. springs are clustered in three groups according to locations:(1) springs on the moraine and talus deposits;(2) springs at the end of alluvial plain in lower topography;(3) springs along the river bank. The hydrometric, geochemical and isotopic data of springs in a representative catchment were integrated and used to elucidate the groundwater flow paths. Results indicate the Quaternary porous aquifers in the alpine catchment have a profound influence on the regional groundwater flow paths and the groundwater and surface water(GW-SW) interactions. The aquifer consisting of alluvial-pluvial deposits has a great capacity of groundwater storage and plays a vital role in regulating discharge by attenuating the seasonal variation and maintaining the main stream in cold seasons. This is different from the fast recharge and discharge mode of the moraine and talus deposits. Our work highlights the importance of loose deposits in controlling the GW-SW interactions in the cold alpine area.

关键词： springs alpine catchments groundwater groundwater-surface water interactions alluvial plain

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Failure Analysis of Aviation Torsional springs

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Chinese Journal of Aeronautics 2011年第4期24卷 527-532页

作者： HOU Weiguo ZHANG Weifang LIU Xiao WANG Zongren DING Meili School of Reliability and System Engineering Beihang University Beijing 100191 China

Cracks and fractures occur during the assembly process to a type of torsional springs used in the aviation mechanism. Besides visual examination, other experimental techniques used for the investigation are： 1） fracture characteristics, damage morphology and fractography by scanning electron microscopy （SEM）, 2） spectrum analysis of covering, 3） metallographic observation of cracks and 4） hydrogen content testing. The results are obtained through the analysis of manufacture process and experimental data. Since no changes of microstructure are found, failures are irrelevant to the material. The cracks and fractures initiate on the inner surface, cracks initiate before the cadmium plating and after the winding. No obvious stress corrosion cracks are found near the crack source region. The opening direction of cracks is consistent with the residual tensile stress of the spring inner surface, and the springs are easy to contact hydrogen media between the spring winding and the cadmium plating. The cracks are caused by hydrogen-induced delayed cracking under the action of the residual tensile stress and hydrogen.

关键词： springs failure residual stress hydrogen-induced delayed cracking

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On Generating Expected Kinetostatic Nonlinear Stiffness Characteristics by the Kinematic Limb-Singularity of a Crank-Slider Linkage with springs

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Chinese Journal of Mechanical Engineering 2019年第3期32卷 33-41页

作者： Baokun Li Guangbo Hao School of Mechanical Engineering Anhui University of Science and TechnologyHuainan 232001China School of Engineering University College CorkCork T12K8AFIreland

Being different from avoidance of singularity of closed-loop linkages, this paper employs the kinematic singularity to construct compliant mechanisms with expected nonlinear stiffness characteristics to enrich the methods of compliant mechanisms synthesis. The theory for generating kinetostatic nonlinear stiffness characteristic by the kinematic limb-singularity of a crank-slider linkage is developed. Based on the principle of virtual work, the kinetostatic model of the crank-linkage with springs is established. The influences of spring stiffness on the toque-position angle relation are analyzed. It indicates that corresponding spring stiffness may generate one of four types of nonlinear stiffness characteristics including the bi-stable, local negative-stiffness, zero-stiffness or positive-stiffness when the mechanism works around the kinematic limb-singularity position. Thus the compliant mechanism with an expected stiffness characteristic can be constructed by employing the pseudo rigid-body model of the mechanism whose joints or links are replaced by corresponding flexures. Finally, a tri-symmetrical constant-torque compliant mechanism is fabricated, where the curve of torque-position angle is obtained by an experimental testing. The measurement indicates that the compliant mechanism can generate a nearly constant-torque zone.

关键词： Kinematic singularity Mechanism with springs Kinetostatic model Nonlinear stiffness

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Origin and circulation of saline springs in the Kuqa Basin of the Tarim Basin,Northwest China

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Journal of Arid Land 2020年第2期12卷 331-348页

作者： SHAN Junjie WANG Jianping SHAN Fashou TENG Xueming FAN Qishun LIQingkuan QIN Zhanjie ZHANG Xiangru Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt LakesChinese Academy of SciencesXining 810008China Key Laboratory of Salt Lake Geology and Environment of Qinghai Province Xining 810008China University of Chinese Academy of Sciences Beijing 100085China Tianjin Center China Geological SurveyTianjin 300170China

It is widely accepted that hydrogeochemistry of saline springs is extremely important to understand the water circulation and evolution of saline basins and to evaluate the potential of potassium-rich evaporites.The Kuqa Basin,located in the northern part of the Tarim Basin in Northwest China,is a saline basin regarded as the most potential potash-seeking area.However,the origin and water circulation processes of saline springs have yet to be fully characterized in this saline basin.In this study,a total of 30 saline spring samples and 11 river water samples were collected from the Qiulitage Structural Belt(QSB)of the Kuqa Basin.They were analyzed for major(K^+,Ca2^+,Na^+,Mg2^+,SO42-,Cl-and HCO3-)and trace(Sr2^+and Br-)ion concentrations,stable H-O-Sr isotopes and tritium concentrations in combination with previously published hydrogeochemical and isotopic(H-O)data in the same area.It is found that the water chemical type of saline springs in the study area belonged to the Na-Cl type,and that of river water belonged to the Ca-Mg-HCO3-SO4 type.The total dissolved solid(TDS)of saline springs in the QSB ranged from 117.77 to 314.92 g/L,reaching the brine level.On the basis of the general chemical compositions and the characteristics of the stable H-O-Sr isotopes of saline springs,we infer that those saline springs mainly originated from precipitation following river water recharging.In addition,we found that saline springs were not formed by evapo-concentration because it is unlikely that the high chloride concentration of saline springs resulted in evapo-concentration and high salinity.Therefore,we conclude that saline spring water may have experienced intense evapo-concentration before dissolving the salty minerals or after returning to the surface.The results show that the origin of salinity was mainly dominated by dissolving salty minerals due to the river water and/or precipitation that passed through the halite-rich stratum.Moreover,there are two possible origins of saline springs in the QSB:one is the infiltr

关键词： H-O-Sr isotopes tritium concentration saline springs meteoric water Qiulitage Structural Belt

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Analytical and Experimental Study of Free Vibration of Beams Carrying Multiple Masses and springs

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Journal of Marine Science and Application 2014年第1期13卷 32-40页

作者： Zhuang Wang Ming Hong Junchen Xu Hongyu Cui School of Naval Architecture Engineering Dalian University of Technology

The structures in engineering can be simplified into elastic beams with concentrated masses and elastic spring supports. Studying the law of vibration of the beams can be a help in guiding its design and avoiding resonance. Based on the Laplace transform method, the mode shape functions and the frequency equations of the beams in the typical boundary conditions are derived. A cantilever beam with a lumped mass and a spring is selected to obtain its natural frequencies and mode shape functions. An experiment was conducted in order to get the modal parameters of the beam based on the NExT-ERA method. By comparing the analytical and experimental results, the effects of the locations of the mass and spring on the modal parameter are discussed. The variation of the natural frequencies was obtained with the changing stiffness coefficient and mass coefficient, respectively. The findings provide a reference for the vibration analysis methods and the lumped parameters layout design of elastic beams used in engineering.

关键词： elastic beams concentrated masses springs naturalfrequencies mode shape functions free vibration NExT-ERA modal identification

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Mapping Landscape Positions and Relevance of Two Dambo-springs in Incalaue River Basin in Niassa Special Reserve,Mozambique:Information for Drought Water Shortage Effects Management

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Journal of Environmental Science and Engineering(B) 2021年第6期10卷 211-226页

作者： Ezrah Natumanya Natasha Ribeiro Majaliwa Jackson Gilbert Mwanjalolo Franziska Steinbruch Faculdade de Agronomia e Engenharia Florestal Universidade Eduardo MondlaneAvenida Julius Nyerere 3453Maputo Mozambique College of Agricultural and Environmental Sciences Makerere UniversityP.O.Box 7062KampalaUganda National Administration for Conservation Areas National Administration for Conservation AreasAvenida 10 de Novembronº40Praceta 1196Maputo Mozambiquenº40Praceta 1196Maputo Mozambique

Mapping of topography and land use/cover as well as spring water yield measurements were done for 2 dambo-spring fed micro-catchments in Incalaue river catchment.The springs are located near Ntimbo 1 and Lizongole human settlement areas in Niassa Special Reserve(NSR).Community consultations were used to asses locally perceived knowledge of dambo-spring catchments dependence by these communities and wildlife;as well as changes and experiences.The Ntimbo 1 dambo-spring catchment(26.55 sq.km)has elevation gradient of 310 to 530 m a.s.l;and the area can topographically be linked to Incalaue river by delineation from a 90-meter spatial resolution Digital Elevation Model(DEM).The Lizongole dambo-spring catchment(1.33 sq.km)has elevation gradient of 300 to 360 m a.s.l and cannot easily be delineated from 90-meter DEM.Both catchments have the 6 vegetation classes existing in the area as well as farmlands and human settlement areas.There exists potential for wildlife-human water source conflict due to dambo dependence by humans and wildlife in the dry season.Ntimbo dambo-spring had a higher water yield per second than the Lizongole dambo-spring.There was no significant difference in spring yields of Ntimbo and Lizongole in the dry season(P<0.05).The Lizongole spring could not be gauged in the wet season because of the wet dambo valley wetland location.There was no significant reduction in water yield for Ntimbo spring during the dry season(P<0.05).The study suggests that Ntimbo spring could be from a confined aquifer;and Lizongole spring to be from a shallow unconfined aquifer.This study contributes understanding of the poorly-defined dambo areas by adding the role of groundwater in supporting micro-dambos which support herbaceous flora and graminivorous fauna as well as human populations in Incalaue basin in NSR especially in the dry season.

关键词： Dambos mapping wildlife source springs

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Abundance and Diversity of the Phototrophic Microbial Mat Communities of Sulphur Mountain Banff springs and Their Significance to the Endangered Snail, <i>Physella johnsoni</i>

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Open Journal of Ecology 2014年第8期4卷 488-516页

作者： Michael Bilyj Dwayne Lepitzki Elizabeth Hughes Jolantha Swiderski Erko Stackebrandt Charlie Pacas Vladimir V. Yurkov Banff National Park Office Banff Canada Department of Microbiology University of Manitoba Winnipeg Canada DSMZ—Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH Braunschweig Germany

Seasonal population fluctuations and diversity of anoxygenic phototrophs and cyanobacteria at the Sulphur Mountain thermal springs, Banff, Canada were investigated and compared to drastic population changes of the endangered snail Physella johnsoni. The microbial community revealed new species of anoxygenic phototrophic bacteria with novel spectral and morphological characteristics. Major mat-forming organisms included densely growing Thiothrix-like species, oxygenic phototrophs of the genera Spirulina, Oscillatoria, and Phormidium and purple nonsulfur bacteria Rhodobacter, Rhodopseudomonas and Rhodomicrobium. Aerobic anoxygenic phototrophs comprised a significant portion, upwards of 9.6 × 104 CFU/cm2 of mat or 18.9% of total aerobic heterotrophic isolates, while PNSB and purple sulfur bacteria were quantified at maximum abundance of 3.2 × 105 and 2.0 × 106 CFU/cm2 of mat, respectively. Photosynthetic activity revealed incredibly productive carbon fixation rates, averaging 40.5 mg C/cm2/day at one studied spring system. A temporal mismatch was observed for mat area and available organics to the fluctuation of P. johnsoni population in a tracking inertia manner. Mat chlorophyll a content appeared directly proportional to snail numbers making it an appropriate indicator of population. This survey of the Sulphur springs microbial communities suggests that phototrophic species are among the main determinants to the proliferation of P. johnsoni.

关键词： Physella johnsoni Cyanobacterial Mats Thermal springs Banff Canada Phototrophic Bacteria

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Hydrochemical characteristics of the major water springs in the Yarmouk Basin, north Jordan

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Natural Science 2011年第1期3卷 28-35页

作者： Awni T. Batayneh 不详

The water quality of major springs in the Yar-mouk Basin (north Jordan) experienced degra-dation due to rapid urbanization and industri-alization. In order to check their suitability for irrigation, drinking and industrial purposes, a research work was conducted to assess the degree of ionic toxicity in these water sources. Thirty-six water samples were analyzed for dif-ferent elements of dominant cations and anions such as Ca, Mg, Na, K, Fe, and HCO3 together with other minor ions P, B, NO3, SO4, and Cl. To classify water quality, parameters such as so-dium adsorption ratio (SAR), soluble sodium percentage (SSP) and residual sodium carbon-ate (RSC) were calculated. Concentrations of major cations and anions are low compared to their permissible levels in potable water. The total dissolved solids is 617 mg/l or below, which indicates the presence of fresh water. The fresh water condition is also verified by low to mod-erate electrical conductivity (347-1234 ?S/cm) and lower than 8.09 pH values. The concentra-tion of total iron (0.0-0.09 mg/l) falls below the maximum permissible limit of 1 mg/l. The low SAR (0.5 to 1.34) coupled with low electrical conductivity, gives the water medium salinity hazard and low sodium hazard. Thus, the water is general of suitable chemical quality for do-mestic, agricultural and most industrial uses.

关键词： Water springs Water Quality Yarmouk Basin North Jordan

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Relationship between Selected Hydrochemical Parameters in springs of Najaf Province, Iraq

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Engineering（科研） 2015年第6期7卷 337-346页

作者： Saadi A. M. Al-Dahaan Abdelkadhum J. Alabidi Nadhir Al-Ansari Sven Knutsson Department of Geology Faculty of Science University of Kufa Kufa Iraq Department of Civil Environmental and Natural Resources Engineering Lulea University of Technology Lulea Sweden

Several springs exist at the south-western desert of Iraq in Najaf Province at latitude 31°00' - 32°15' and longitude 43°30' - 44°30'. They are almost parallel to Euphrates River on the eastern edge of western desert. General direction for the distribution of springs coincides with that of faults running northwest-southeast. The Hydrogen sulfide, temperature, pH and electrical conductivity were investigated in these springs. The analyses indicated that the concentration of H2S decreased from northwest toward southeast which is attributed to the escape of this gas to the atmosphere during the flow of groundwater near or on the earth surface. The surrounding geologic conditions did not affect the temperature and pH of the springs. Electrical conductivity showed an increase from northwest towards southeast which reflects dissolving more ions from the rocks of the aquifer. The electrical conductivity and hydrogen sulfide concentration had reverse relationship.

关键词： Najaf springs Electrical Conductivity pH Iraq

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Planar System-Masses in an Equilateral Triangle:Numerical Study within Fractional Calculus

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Computer Modeling in Engineering & Sciences 2020年第9期124卷 953-968页

作者： Dumitru Baleanu Behzad Ghanbari Jihad H.Asad Amin Jajarmi Hassan Mohammadi Pirouz Department of Mathematics Faculty of Arts and SciencesCankaya UniversityAnkara06530Turkey Institute of Space Sciences Bucharest76900Romania Department of Engineering Science Kermanshah University of TechnologyKermanshahIran Department of Physics College of Arts and SciencesPalestine Technical UniversityTulkarmPalestine Department of Electrical Engineering University of BojnordBojnordIran

In this work,a system of three masses on the vertices of equilateral triangle is investigated.This system is known in the literature as a planar system.We first give a description to the system by constructing its classical Lagrangian.Secondly,the classical Euler-Lagrange equations(i.e.,the classical equations of motion)are derived.Thirdly,we fractionalize the classical Lagrangian of the system,and as a result,we obtain the fractional Euler-Lagrange equations.As the final step,we give the numerical simulations of the fractional model,a new model which is based on Caputo fractional derivative.

关键词： Planar system masses in equilateral triangle springs Euler-Lagrange equations fractional derivative

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