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Characteristics of daily extreme wind gusts on the Qinghai-Tibet Plateau, China

Journal of Arid Land 2018年第5期10卷 673-685页

作者： YAO Zhengyi LI Xiaoying XIAO Jianhua Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou 730000 China gansu center for sand hazard reduction engineering and technology Lanzhou 730000 China

Severe wind is a major natural hazard and a main driver of deserdficadon on the Qinghai-Tibet Plateau. Generally, studies of Qinghai-Tibet Plateau＇s wind climatology focus on mean wind speeds and its gust speeds have been seldom investigated. Here, we used observed daily maximum gust speeds from a 95- station network over a 5-year period （2008-2012） to analyze the characteristics of extreme wind speeds and directions by fitting Weibull and Gumbel distributions. The results indicated the spatial distribution of extreme wind speeds and their direction on the Qinghai-Tibet Plateau is highly variable, with its western portion prone to greater mean speeds of extreme wind gusts than its eastern portion. Maximum extreme wind speeds of 30.9, 33.0, and 32.2 m/s were recorded at three stations along the Qinghai Tibet Railway. Severe winds occurred mostly from November to April, caused primarily by the westerly jet stream. Terrain greatly enhances the wind speeds. Our spatial analysis of wind speed data showed that the wind speeds increased exponentially with an increasing altitude. We also assessed the local wind hazard by calculating the return periods of maximum wind gusts from the observational data based on the statistical extreme value distributions of these wind speeds. Further attention should be given to those stations where the yearly maximum daily extreme wind speed increased at a rate greater than that of mean value of daily extreme wind speeds. Severe extreme wind events in these regions of the plateau are likely to become more frequent. Consequently, building structural designers working in these areas should use updated extreme wind data rather than relying on past data alone.

关键词： extreme wind gusts wind direction wind hazard wind speeds Qinghai-Tibet Plateau

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Quantitative analysis on the dynamic characteristics of megadunes around the Crescent Moon Spring, China

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Journal of Arid Land 2014年第3期6卷 255-263页

作者： YingJun PANG JianJun QU KeCun ZHANG ZhiShan AN QingHe NIU Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Dunhuang Gobi and Desert Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences gansu center for sand hazard reduction engineering and technology

The Crescent Moon Spring is a precious natural heritage. However, the dynamic characteristics of megadunes around the Crescent Moon Spring are not well known. This paper quantitatively studied the character- istics and changes of megadunes around the Crescent Moon Spring by interpreting aerial photographs taken in 1985 and 2004 and analysing the dune crestlines and the wind data collected from 2011 to 2012. Results revealed that pyramid dunes were formed by a complex wind regime. The Crescent Moon Spring was not buried by shifting sands because of the stable wind regime and relative stability of pyramid dunes. The crestlines of the dunes around the spring moved northward between 1985 and 2004. The south-facing slip faces were also exposed to wind ero- sion, whereas the other faces were under deposition, thus indicating that the southerly wind was relatively en- hanced. Limiting the scale of tall windbreaks and architectures in the Dunhuang oasis at the north of the spring was necessary to maintain the dynamic equilibrium of the wind regime and sand transport.

关键词： Dunhuang city Crescent Moon Spring pyramid dunes dynamic characteristics erosion and deposition

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Morphology and formation mechanism of sand shadow dunes on the Qinghai-Tibet Plateau

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Journal of Arid Land 2015年第1期7卷 10-26页

作者： JianHua XIAO JianJun QU ZhengYi YAO YingJun PANG KeCun ZHANG Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Dunhuang Gobi and Desert Ecology and Environment Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences gansu center for sand hazard reduction engineering and technology

The formation and development of dunes depend on wind-blown sand movement which is affected by the characteristics of sand material, topography, wind regimes and other factors. In this paper, we investigated two sand shadow dune groups in Shigatse and Za＇gya Zangbo of Tibet and an individual dune in Da Qaidam of Qinghai, and analyzed their topographies and morphologies, and the physical characteristics of the sand, wind regime and sand transport. Formed under harsh conditions behind hills, these mature sand shadow dunes are hundreds of meters long, have significant ridges and crescent dunes downwind, and have a hill pass on one or both sides. Wind tunnel experiments revealed that the hill gap and wind velocity are important factors in the formation of these dunes sand shadow dunes formed only when the gap spacing is two-thirds of the hill height. When wind velocities are 20 m/s, the sand body is divided into two parts. The hill pass allows the transport of sand by wind, creating a ＂nar- row-pipe effect＂, which causes the transported material to gradually accumulate in the center of the shadow zone. We observed that the following are needed for sand shadow dunes to form：（1） strong winds, sufficient sand, suitable obstacles and a dry climate; （2） one or both sides of the obstacle forming the shadow zone must have a hill pass; and （3） the windward side of the obstacle must have a wide, flat area, providing adequate spacing for wind flow and transport of material and the leeward side must have a sufficiently broad, flat area to allow the release of the transported material. Research results on these newly discovered dunes on the Qinghai-Tibet Plateau could contribute to the understanding of dune geomorphology.

关键词： sand shadow dune morphology aeolian landform wind tunnel Qinghai-Tibet Plateau

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Influence of Golmud-Lhasa Section of Qinghai-Tibet Railway on Blown sand Transport

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Chinese Geographical Science 2015年第1期25卷 39-50页

作者： XIAO Jianhua YAO Zhengyi QU Jianjun Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Dunhuang Gobi and Desert Ecology and Environment Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences gansu center for sand hazard reduction engineering and technology

The Qinghai-Tibet Railway(QTR) passes through 281 km of sandy land, 11.07 km of which causes serious sand damage to the railway and thus, the control of blown sand is important for the safe operation of the railway. Construction of the railway and sand prevention system greatly changed the blown sand transport of the primary surface. Effective and feasible sand-control measures include stone checkerboard barriers(SCBs), sand fences(SFs), and gravel coverings. This study simulated the embankments, SCBs and SFs of the QTR in a wind tunnel, and analyzed their respective wind profile, sand deposition, and sand-blocking rate(SBR) in conjunction with field data, aiming at studying the influence of Golmud-Lhasa section of the QTR and sand prevention system on blown sand transport. The results of wind tunnel experiments showed that wind speed increased by 67.7%–77.3% at the upwind shoulder of the embankment and decreased by 50.0%–83.3% at upwind foot of embankment. Wind speed decreased by 50.0%–100.0% after passing through the first SF, and 72.2%–100.0% after the first row of stones within the first SCB grid. In the experiment of sand deposition, the higher the wind speed, the lower the SBR of SCB and SF. From field investigation, the amount of sand blocked by the four SFs decreased exponentially and its SBR was about 50.0%. By contrast, SCB could only block lower amounts of sand, but had a higher SBR(96.7%) than SF. Although, results show that SFs and SCBs along the Golmud-Lhasa section of the QTR provide an obvious sand blocking effect, they lead to the deposition of a large amount of sand, which forms artificial dunes and becomes a new source of sand damage.

关键词： Qinghai-Tibet Railway(QTR) wind profile blown sand transport sand damage wind tunnel

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Thermodynamic Effects on Particle Movement:Wind Tunnel Simulation Results

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Chinese Geographical Science 2012年第2期22卷 178-187页

作者： NIU Qinghe QU Jianjun ZHANG Kecun LIU Xianwan Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Dunhuang Gobi and Desert Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Dunhuang 736200 China gansu center for sand hazard reduction engineering and technology Lanzhou 730000 China

sand/dust storms are some of the main hazards in arid and semi-arid zones. These storms also influence global environmental changes. By field observations, empirical statistics, and numerical simulations, pioneer researchers on these natural events have concluded the existence of a positive relationship between thermodynamic effects and sand/dust storms. Thermodynamic effects induce an unsteady stratified atmosphere to influence the process of these storms. However, studies on the relationship of thermodynamic effects with particles (i.e., sand and dust) are limited. In this article, wind tunnel with heating was used to simulate the quantitative relationship between thermodynamic effects and particle movement on different surfaces. Compared with the cold state, the threshold wind velocity of particles is found to be significantly decrease under the hot state. The largest decrease percentage exceedes 9% on fine and coarse sand surfaces. The wind velocity also has a three-power function in the sand transport rate under the hot state with increased sand transport. Thermodynamic effects are stronger on loose surfaces and fine particles, but weaker on compacted surfaces and coarse particles.

关键词： thermodynamic effect threshold wind velocity nel simulation drifting sand flux structure sand transport rate wind tunnel simulation

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New discoveries on the effects of desertification on the ground temperature of permafrost and its significance to the Qinghai-Tibet Plateau

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Chinese Science Bulletin 2012年第8期57卷 838-842页

作者： XIE ShengBo QU JianJun ZU RuiPing ZHANG KeCun HAN QingJie Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy ofSciencesLanzhou 730000China Dunhuang Gobi and Desert Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy ofSciencesDunhuang 736200China gansu center for sand hazard reduction engineering and technology Lanzhou 730000China

The desert and permafrost conditions of the Qinghai-Tibet Plateau are ***,the effects of desertification on the ground temperature of permafrost are currently ***,understanding this problem has become more urgent because of increasing desertification on the *** this reason,an observational field experiment was undertaken by the authors at Honglianghe on the Qinghai-Tibet *** ground temperature probes were used,and synchronized contrasting observations were made in an open *** of the ground temperature of permafrost below sand layers with a range of thicknesses were made from May 2010 to April *** sand layers were found to play a key role in the protection of the underlying *** ground temperature below a permafrost table overlain by a thick sand layer was lower than that of the average annual temperature for the natural ground surface,and the temperature drop was roughly constant at 0.2°*** the warmer part of the year (May to September),the maximum temperature drops over the five months were 3.40,3.72,4.85,3.16,and 1.88°C,*** ground temperature near a permafrost table overlain by a thin sand layer was also lower than that of the average annual temperature for the natural ground ***,in this case the average of the annual maximum temperature drop was significantly less,0.71°*** scientific significance of our preliminary conclusions is not only to present an exploration of the interaction between desertification and permafrost,but also to provide new engineering ideas for protecting the permafrost in regions where construction is required on the Qinghai-Tibet Plateau.

关键词：多年冻土地区青藏高原地温观测荒漠化地面温度田间试验热敏电阻最高温度

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Mechanism of high-concentration electrolyte inhibiting the destructive effect of Mn(Ⅱ)on the performance of lithium-ion batteries

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Journal of Energy Chemistry 2023年第3期78卷 381-392,I0011页

作者： Xiaoling Cui Jinlong Sun Dongni Zhao Jingjing Zhang Jie Wang Hong Dong Peng Wang Junwei Zhang Shumin Wu Linhu Song Ningshuang Zhang Chunlei Li Shiyou Li School of Petrochemical technology Lanzhou University of TechnologyLanzhou 730050GansuChina Key Laboratory of Low Carbon Energy and Chemical engineering of gansu Province Lanzhou 730050GansuChina gansu engineering Laboratory of Electrolyte Material for Lithium-ion Battery Baiyin 730900GansuChina

By optimizing electrolyte formulation to inhibit the deposition of transition metal ions(TMIs) on the surface of the graphite anode is an effective way to improve the electrochemical performance of lithium-ion *** present,it is generally believed the formation of an effective interfacial film on the surface of the anode electrode is the leading factor in reducing the dissolution of TMIs and prevent TMIs from being embedded in the *** ignores the influence of the solvation structures in the electrolyte system with different composition,and is not conducive to the design of the electrolyte formulation from the perspective of changing the concentration and the preferred solvent to inhibit the degradation of battery performance caused by TMIs *** this work,by analyzing the special solvation structures of the high-concentra tion electrolyte,we study the main reason why high-concentration electrolyte inhibits the destructive effect of Mn(Ⅱ) on the electrochemical performance of *** combining the potentialresolved in-situ electrochemical impedance spectroscopy technology(PRIs-EIS) and density functional theory(DFT) calculation,we find that Mn(Ⅱ) mainly exists in the form of contact ions pairs(CIPs) and aggregates(AGGs) in high-concentration *** solvation structures can reduce the destructive effect of Mn(Ⅱ) on battery performance from two aspects:on the one hand,it can rise the lowest unoccupied orbital(LUMO) value of the solvation structures of Mn(Ⅱ),thereby reducing the chance of its reduction;on the other hand,the decrease of Mn2+ions reduction can reduce the deposition of metallic manganese in the solid electrolyte interphase(SEI),thereby avoiding the continuous growth of the *** study can be provided inspiration for the design of electrolytes to inhibit the destructive effect of TMls on LIBs.

关键词： Lithium-ion battery High-concentration electrolyte Manganese deposition Solvation structures

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Analyses on the Types,Distributions and Characteristics of Vegetation and Soil along Qinghai-Tibet Railway

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Meteorological and Environmental Research 2013年第9期4卷 15-18页

作者： Shengbo Xie Jianjun Qu Key Laboratory of Desert and Desertification/Dunhuang Gobi and Desert Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences gansu center for sand hazard reduction engineering and technology

[Objeective] The research aimed to study the types, distributions and characteristics of vegetation and soil along Qinghai -Tibet Rail- way. [ Method]Types, distributions and characteristics of vegetation and soil along Qinghai -Tibet Railway were studied by field investigation meth- od. [Result] The vegetation along Qinghai -Tibet Railway was dominated by alpine grassland and meadow, while the soil was dominated by alpine steppe soil and meadow soil corresponding along the railway. They both concentrated distnbutions at the section from Kunlun Mountain to Nyainqen- tanglha Mountain. [ Conclusion] The research could provide the basis for disaster control and resource development of Qinghai-Tibet Railway.

关键词： Qinghai-Tibet Railway Vegetation Soil China

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Glacier extraction based on ASAR,DEM and texture feature of ASAR using SVM in the Western Qilian Mountains,Northwest China

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Research in Cold and Arid Regions 2012年第3期4卷 195-200页

作者： JunZhan Wang JianJun Qu WeiMin Zhang Dunhuang Gobi and Desert Ecology and Environment Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou Gansu 730000 China gansu center for sand hazard reduction engineering and Technoogy Lanzhou Gansu 730000 China

This paper is focused on the method for extracting glacier area based on ENVISAT ASAR Wide Swath Modes （WSM） data and digital elevation model （DEM） data, using support vector machines （SVM） classification method. The digitized result of the glaci- er coverage area in the western Qilian Mountains was extracted based on Enhanced LandSat Thematic Mapper （ETM＋） imagery, which was used to validate the precision of glacier extraction result. Because of similar backscattering of glacier, shadow and wa- ter, precision of the glacier coverage area extracted from single-polarization WSM data using SVM was only 35.4%. Then, texture features were extracted by the grey level co-occurrence matrix （GLCM）, with extracted glacier coverage area based on WSM data and texture feature information. Compared with the result extracted from WSM data, the precision improved 13.2%. However, the glacier was still seriously confused with shadow and water. Finally, DEM data was introduced to extract the glacier coverage area. Water and glacier can be differentiated because their distribution area has different elevations; shadow can be removed from the classification result based on simulated shadow imagery created by DEM data and SAR imaging parameters; finally, the glacier coverage area was extracted and the precision reached to 90.2%. Thus, it can be demonstrated that the glacier can be accurately semi-automatically extracted from SAR with this method. The method is suitable not only for ENVISAT ASAR WSM imagery, but also for other satellite SAR imagery, especially for SAR imagery covering mountainous areas.

关键词： glacier ASAR DEM texture feature

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Ecological-Based Mining:A Coal-Water-Thermal Collaborative Paradigm in Ecologically Fragile Areas in Western China

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engineering 2024年第7期38卷 209-222页

作者： Xiaoxiu Liu Yifan Zeng Qiang Wu Shihao Meng Jiyue Liang Zhuping Hou National engineering Research center of Coal Mine Water hazard Controlling China University of Mining and TechnologyBeijing 100083China College of Geoscience and Surveying engineering China University of Mining and TechnologyBeijing 100083China University of Mining and technology(Beijing)Inner Mongolia Research Institute Ordos 017000China

A substantial reduction in groundwater level,exacerbated by coal mining activities,is intensifying water scarcity in western China’s ecologically fragile coal mining ***’s national strategic goal of achieving a carbon peak and carbon neutrality has made eco-friendly mining that prioritizes the protection and efficient use of water resources *** on the resource characteristics of mine water and heat hazards,an intensive coal-water-thermal collaborative co-mining paradigm for the duration of the mining process is *** integrated system for the production,supply,and storage of mining companion resources is achieved through technologies such as roof water inrush prevention and control,hydrothermal quality improvement,and deep-injection geological *** active preventive and control system achieved by adjusting the mining technology and a passive system centered on multiobjective drainage and grouting treatment are suggested,in accordance with the original geological characteristics and dynamic process of water *** implementing advanced multi-objective drainage,specifically designed to address the“skylight-type”water inrush mode in the Yulin mining area of Shaanxi Province,a substantial reduction of 50%in water drillings and inflow was achieved,leading to stabilized water conditions that effectively ensure subsequent safe coal *** integrated-energy complementary model that incorporates the clean production concept of heat utilization is also *** findings indicate a potential saving of 8419 t of standard coal by using water and air heat as an alternative heating source for the Xiaojihan coalmine,resulting in an impressive energy conservation of 50.2%and a notable 24.2%reduction in carbon *** ultra-deep sustained water injection of 100 m^(3)·h^(-1)in a single well would not rupture the formation or cause water leakage,and 7.87×10^(5)t of mine water could be effectively stored in the Liujiagou Formation,presenti

关键词： Dual carbon targets Coal-water-thermal co-mining Ecologically fragile areas Mine-water control Resource utilization

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