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供需平衡视角下昆仑山北坡县域单元地表水资源开发利用潜力初探

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干旱区地理 2024年第7期47卷 1106-1115页

作者：周洪华杨玉海朱成刚方功焕中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室干旱区生态安全与可持续发展重点实验室新疆乌鲁木齐830011

定量分析地表水资源开发利用潜力有助于明晰区域水资源禀赋,对区域未来水资源科学规划和可持续开发利用具有重要的指导意义。通过供需水量平衡,从地表径流量、生态需水量、地表水可利用量角度,初步探讨了昆仑山北坡县域单元的地表水资... 详细信息

定量分析地表水资源开发利用潜力有助于明晰区域水资源禀赋,对区域未来水资源科学规划和可持续开发利用具有重要的指导意义。通过供需水量平衡,从地表径流量、生态需水量、地表水可利用量角度,初步探讨了昆仑山北坡县域单元的地表水资源开发利用潜力,以期为昆仑山北坡科学规划和兵团南进布局提供水资源保障依据。结果表明:(1)昆仑山北坡河流径流2000年后呈显著增加趋势,主要河流2001—2010年年均径流量较2000年以前平均增加了23.36%,2011—2020年较2000年以前平均增加了42.89%,其中车尔臣河增幅最大,和田河增幅最小。(2)车尔臣河流域、克里雅河流域和和田河流域的生态基流量分别为4.67×10^(8)m^(3)、5.38×10^(8)m^(3)和20.26×10^(8)m^(3),天然植被生态需水量分别为4.34×10^(8)m^(3)、4.00×10^(8)m^(3)和2.62×10^(8)m^(3)。(3)昆仑山北坡各县域单元现状地表水已用水量范围为0.1×10^(8)~8.73×10^(8)m^(3),地表水资源潜力范围为-0.07×10^(8)~3.17×10^(8)m^(3),空间差异非常显著,其中水资源潜力大于2.00×10^(8)m^(3)的有墨玉县、铁门关市38团、策勒县、且末县、和田县、民丰县和洛浦县。现状区域的地表水资源调蓄能力不足,水资源利用上限偏低,虽有潜力但有水难用,未来昆仑山北坡各县域单元需制定修编更为适宜的地表水资源规划并加强基础水利工程建设,提升地表水资源利用效率,为区域高质量发展提供水资源支撑保障。

关键词：昆仑山北坡地表径流供需平衡生态需水地表水资源潜力

Impact of land use/cover changes on carbon storage in a river valley in arid areas of Northwest China

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Journal of Arid Land 2017年第6期9卷 879-887页

作者： yang yuhai LI Weihong ZHU Chenggang WANG yang HUANG Xiang Key Laboratory of Oasis Ecology and Desert Environment Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences College of Pratacultural and Environmental Sciences Xinjiang Agricultural University

Soil carbon pools could become a CO_2 source or sink, depending on the directions of land use/cover changes. A slight change of soil carbon will inevitably affect the atmospheric CO_2 concentration and consequently the climate. Based on the data from 127 soil sample sites, 48 vegetation survey plots, and Landsat TM images, we analyzed the land use/cover changes, estimated soil organic carbon（SOC） storage and vegetation carbon storage of grassland, and discussed the impact of grassland changes on carbon storage during 2000 to 2013 in the Ili River Valley of Northwest China. The results indicate that the areal extents of forestland, shrubland, moderate-coverage grassland（MCG）, and the waterbody（including glaciers） decreased while the areal extents of high-coverage grassland（HCG）,low-coverage grassland（LCG）, residential and industrial land, and cultivated land increased. The grassland SOC density in 0–100 cm depth varied with the coverage in a descending order of HCG〉MCG〉*** regional grassland SOC storage in the depth of 0–100 cm in 2013 increased by 0.25×1011 kg compared with that in 2000. The regional vegetation carbon storage（S_（rvc）） of grassland was 5.27×10~9 kg in2013 and decreased by 15.7% compared to that in 2000. The vegetation carbon reserves of the under-ground parts of vegetation（S_（ruvb）） in 2013 was 0.68×10~9 kg and increased by approximately 19.01%compared to that in 2000. This research can improve our understanding about the impact of land use/cover changes on the carbon storage in arid areas of Northwest China.

关键词： land use/cover organic carbon grassland global change Ili River Valley

花状CoMOF中间层修饰钯/泡沫镍电极对三氯乙酸脱氯研究

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环境科学学报 2024年第4期44卷 11-21页

作者：杨玉海王方园蒋纪华谢欢庆张彬庞思婕裘建平浙江师范大学行知学院地理与环境科学学院金华321004 金华信诺达环境技术服务有限公司金华321100

针对常规污染控制技术难以去除饮用水中三氯乙酸(Trichloroacetic acid,TCAA)的问题,制备了花状CoMOF中间层修饰钯/泡沫镍电极(Pd/CoMOF/RNF),采用SEM、TEM、XRD、XPS等方法对其进行表征分析,探究了Pd/CoMOF/RNF电极对TCAA的还原脱氯影... 详细信息

针对常规污染控制技术难以去除饮用水中三氯乙酸(Trichloroacetic acid,TCAA)的问题,制备了花状CoMOF中间层修饰钯/泡沫镍电极(Pd/CoMOF/RNF),采用SEM、TEM、XRD、XPS等方法对其进行表征分析,探究了Pd/CoMOF/RNF电极对TCAA的还原脱氯影响因素和实际潜在应用及脱氯强化机制.结果表明:所制备电极具有中空微米花结构,Pd纳米颗粒均匀分布在CoMOF纳米片上;当阴极电位为-1.0 V、TCAA初始浓度为1 mg·L^(-1)、初始pH值为5.5时,反应90 min后,TCAA降解效率达到最高98.2%,且经过5次循环实验后,TCAA脱氯效率基本不变,具有较好的稳定性;氯乙酸(Chloroacetic acid,CAAs)在60 min后就可降至60μg·L^(-1)以下;结合电化学测试、电子自旋共振谱(Electron spin resonance,ESR)测试和密度泛函理论(Density functional theory,DFT)计算,花状CoMOF中间层的引入增加了电极活性面积,提供更多的活性位点,同时促进电子迁移速率,产生更多具有更强吸附能力H*_(ads),从而有效增强脱氯效率.因此利用Pd/CoMOF/RNF电极电催化还原降解TCAA具有很大的应用潜力.

关键词：电催化加氢脱氯三氯乙酸花状CoMOF Pd/CoMOF/RNF电极

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轮式车辆的路谱疲劳寿命研究和应用

车辆与动力技术 2024年第1期 41-48页

作者：袁金平潘婷杨玉海北奔重型汽车集团有限公司包头014030

轮式车辆面对复杂的自然环境时,整车会受到不同载荷的作用,这通常会引起部分零件疲劳强度失效,影响轮式车辆的性能发挥,这对现代轮式车辆的疲劳强度测试及分析提出了许多新的挑战.本文针对轮式车辆在行驶过程中道路载荷对悬架系统的影... 详细信息

轮式车辆面对复杂的自然环境时,整车会受到不同载荷的作用,这通常会引起部分零件疲劳强度失效,影响轮式车辆的性能发挥,这对现代轮式车辆的疲劳强度测试及分析提出了许多新的挑战.本文针对轮式车辆在行驶过程中道路载荷对悬架系统的影响进行分析,研究建立一套从载荷谱采集、结构疲劳预测的零部件疲劳寿命测试分析方法,为轮式车辆面对不同的应用场景提供切实可行疲劳分析思路和方法.

关键词：道路谱悬架系统疲劳仿真

Water transport and water use efficiency differ among Populus euphratica Oliv. saplings exposed to saline water irrigation

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Journal of Arid Land 2019年第6期11卷 866-879页

作者： ZHOU Honghua CHEN Yaning ZHU Chenggang yang yuhai YE Zhaoxia 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

Populus euphratica *** a unique woody tree that can be utilized for vegetation restoration in arid and semi-arid *** effects of saline water irrigation(0.00, 2.93, 8.78 and 17.55 g/L NaCl solutions) on water transport and water use efficiency(WUE) of *** saplings were researched for improving the survival of *** saplings and vegetation restoration in arid and semi-arid areas of Xinjiang, China in *** showed that hydraulic conductivity and vulnerability to cavitation of *** saplings were more sensitive in root xylem than in twig xylem when irrigation water salinity *** with saline water concentration less than 8.78 g/L did not affect the growth of *** saplings, under which they maintained normal water transport in twig xylem through adjustment of anatomical structure of vessels and kept higher WUE and photosynthesis in leaves through adjustment of ***, irrigation with saline water concentration up to 17.55 g/L severely inhibited the photochemical process and WUE of *** saplings, resulting in severe water-deficit in leaves and a sharp reduction in water transport in ***, it is feasible to irrigate *** forest by using saline groundwater for improving the survival of *** saplings and vegetation restoration in arid and semi-arid areas of Xinjiang, China.

关键词： photosynthesis photochemical process water use efficiency hydraulic conductivity cavitation resistance

On the Friction and Wear Behaviors of Dental Machinable Porcelain

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材料热处理学报 2004年第5B期25卷 1171-1174页

作者： yuhai-yang ZHOUZhong-rong CAIZhen-Bing TribologyResearchInstitute SouthwestJiaotongUniversityChengduChina TribologyResearchInstitute SouthwestJiaotongUniversityChengduChina／／CollegeofHuaxiStomatologySichuanUniversityChengduChina

In order to well design tribosystems of dental CAD-CAM restorations, an understanding of the tribological mechanisms of dental machinable porcelain are essential. The friction and wear behavior of new generation industrially prefabricated Cerec Vitablocs Mark II against uniform Si3N4 ball has been performed using a small amplitude reciprocating apparatus under simulating oral conditions. The loads of 10-40 N, reciprocating amplitudes of 100-500 urn, frequencies of 1-4 Hz and two lubrications (no / artificial saliva lubrication) were selected. Tests lasting up to 10 000 cycles were conducted. The results show that Cerec Vitablocs Mark II record a friction coefficient of 0.55-0.84. Artificial saliva plays a lubricant effect during wear process. Among three parameters of the test on friction coefficient and wear depth of dental machinable porcelains, the load effect is prominent. Abrasive wear is the main wear mechanism, but brittle cracks and delamination are more popular especially under unlubricated friction.

关键词：磨损性能摩擦系数陶瓷材料齿轮

Real-Time Co-optimization of Gear Shifting and Engine Torque for Predictive Cruise Control of Heavy-Duty Trucks

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 294-317页

作者： Hongqing Chu Xiaoxiang Na Huan Liu yuhai Wang Zhuo yang Lin Zhang Hong Chen School of Automotive Studies Tongji UniversityShanghaiChina Department of Engineering University of CambridgeCambridgeUK State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchunChina Qingdao Automotive Research Institute Jilin UniversityQingdaoChina Dongfeng Commercial Vehicle Technology Center Dongfeng Motor CorporationWuhanChina

Fuel consumption is one of the main concerns for heavy-duty *** cruise control(PCC)provides an intriguing opportunity to reduce fuel consumption by using the upcoming road *** this study,a real-time implementable PCC,which simultaneously optimizes engine torque and gear shifting,is proposed for heavy-duty *** minimize fuel consumption,the problem of the PCC is formulated as a nonlinear model predictive control(MPC),in which the upcoming road elevation information is *** the solution of the nonlinear MPC is time consuming;thus,a real-time implementable solver is developed based on Pontryagin’s maximum principle and indirect shooting *** programming(DP)algorithm,as a global optimization algorithm,is used as a performance benchmark for the proposed ***,hardware-in-the-loop and real-truck experiments are conducted to verify the performance of the proposed *** results demonstrate that the MPC-based solution performs nearly as well as the DP-based solution,with less than 1%deviation for testing ***,the proposed co-optimization controller is implementable in a real-truck,and the proposed MPC-based PCC algorithm achieves a fuel-saving rate of 7.9%without compromising the truck’s travel time.

关键词： Heavy-duty truck Predictive cruise control Model predictive control Pontryagin’s maximum principle Real-truck implementation

Distribution of soil organic carbon under different vegetation zones in the Ili River Valley, Xinjiang

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Journal of Geographical Sciences 2010年第5期20卷 729-740页

作者： yang yuhai CHEN Yaning LI Weihong CHEN Yapeng Key Laboratory of Oasis Ecology and Desert Environment Xinjiang Institute of Ecology and Geography CASUrumqi 830011 China

We analyzed and estimated the distribution and reserves of soil organic carbon under nine different vegetation conditions including alpine meadow, meadow steppe, typical steppe, desert steppe, and temperate coniferous forest and so on, in the Ill River valley, Xin- jiang according to data from field investigations and laboratory analyses in 2008 and 2009. The study results show that the soil organic carbon content in the Ili River valley varies with the type of vegetation. In the 0-50 cm soil horizon, the soil organic carbon content is the highest under the vegetation types of alpine meadow and meadow steppe, slightly lower under temperate coniferous forest and typical steppe, and the lowest under the intrazonal vegetation and desert vegetation types. The soil organic carbon content shows basically a tendency to decrease as soil depth increases under various vegetation types except in the case of the intrazonal vegetation. Similarly, the soil organic carbon density is the highest and varies little under the vegetation types of alpine meadow, meadow steppe and temperate coniferous forest, and is the lowest under the desert vegetation type. Both the soil organic carbon content and density in the topsoil of meadows in the Ili River valley are high, so pro- tecting meadows in the Ili River valley, and especially their topsoil, should be a priority so that the potential of change in soil organic carbon in the shallow soil horizon is reduced, and this means maintenance of the stability of the soil carbon pool.

关键词： vegetation grassland soil organic carbon Ili River Valley

Arbuscular mycorrhizal fungi infection in desert riparian forest and its environmental implications: A case study in the lower reach of Tarim River

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Progress in Natural Science:Materials International 2008年第8期18卷 983-991页

作者： yuhai yang, Yaning Chen *, Weihong Li Key Laboratory of Oasis Ecology and Desert Environment, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China Key Laboratory of Oasis Ecology and Desert Environment Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

This study was conducted on the desert riparian forest along the lower reach of the inland Tarim River, which is located in the arid region of Northwest *** plant species in 10 families were collected from five monitoring sections,and examined for the infection of arbuscular mycorrhizal fungi (AMF). The impact of different soil factors on AMF infection rate and intensity was compared using the principal component analysis (PCA) method. The results indicate that 11 species are AM and only 4 are non-AM plants. The estimated capacity of AMF infection depends on families of plants and also the parameters (infection rate, infection intensity, fungal spore density) used. The density of fungal spores was relatively higher in Phragmites communis and Populus euphratica in Graminaceae and Salicaceae families, *** infection rate was above 50%in all the AM plants,except Calligonum *** highest infection rate appeared in Alhagi sparsifolia (97%) and Glycyrrhiza inflata (92%). However, when compared by AMF infection intensity, Tamarix spp. became the top one, followed by Alhagi sparsifolia, and Glycyrrhiza inflata was in the middle range of all the species. The PCA has identified that soil total salt, moisture, organic matter, total nitrogen, total P, available K and pH were closely associated with the AMF infection.

关键词： Arbuscular mycorrhiza Infection Ecological restoration Desert riparian forest Soil