Article
Environmental Sciences
Kaihui Li, Xuejun Liu, Fengzhan Geng, Wen Xu, Jinling Lv, Anthony J. Dore
Summary: The study found significant spatial heterogeneity in atmospheric nitrogen deposition in arid Central Asia, with varying deposition velocities. Nitrogen deposition varied across different ecosystems, with the order being desert < grassland < desert-grassland < forest < farmland < city/suburb.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Environmental Sciences
Iva Hunova, Martin Novak, Pavel Kurfurst, Hana Skachova, Marketa Stepanova, Eva Prechova, Frantisek Veselovsky, Jan Curik, Leona Bohdalkova, Arnost Komarek
Summary: Nitrogen (N) deposition is crucial for atmospheric self-cleaning and plays a significant role in nutrient and pollutant transportation into ecosystems. This study analyzed N-NO3- concentrations in rime and snow samples collected from Czech plots in the winters of 2009-2011. The results were compared with geostatistical modeling data to examine the impact of industrialization and differences between winters on N-NO3- concentrations. The study revealed significantly higher N-NO3- concentrations in rime compared to snow, with larger variations between sites for rime. The findings highlight the importance of vertical deposition, specifically snow, as the dominant pathway for N-NO3- input in winter.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Zhang Baijuan, Li Zongxing, Feng Qi, Gui Juan, Zhao Yue, Zhang Baiting
Summary: This study conducted an observational study on the Qilian Mountains and analyzed precipitation data to quantify the N deposition in the transition zone between the Tibetan Plateau and the arid region. The results showed that NO3?-N deposition was the main form of wet deposition of atmospheric N, and altitude, meteorological factors, and ecosystem types influenced the wet deposition. This study provides a scientific basis for environmental protection in the transition zone.
Article
Environmental Sciences
Alessandra Teglia, Daniela Di Baccio, Giorgio Matteucci, Andrea Scartazza, Bruno De Cinti, Francesco Mazzenga, Dario Ravaioli, Enrico Muzzi, Graziella Marcolini, Federico Magnani
Summary: Anthropogenic activities have resulted in an increase of nitrogen compounds in the atmosphere, affecting forest ecosystems. This study simulated the effects of nitrogen deposition in beech forests through controlled experiments in two contrasting climatic regions. The results showed that nitrogen addition had some impact on forest health, but no severe impairments were observed in the short term.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Geosciences, Multidisciplinary
Jiaju Zhao, Xiangzhong Li, Yuxin He, Yunning Cao, Jing Hu
Summary: Investigations into the evolution of hydrology in arid regions, both natural and human-induced, are crucial for hydrological forecasts. A study on Lake Tuosu in the northeastern Qaidam Basin revealed a long-term decreasing trend in lake area and inflow after 1850, which were sensitive to westerly-forced winter-spring precipitation. Further analysis showed that enhanced human activities, such as agricultural irrigation, led to rapid shrinkage of Lake Tuosu during 1990-2000. Integrated moisture indices for mountains and basins in southern arid Central Asia exhibited opposing trends, with the humidity gradient from mountains to basins increasing after 1850. This change in hydrological system, beyond natural variation, is believed to be linked to the migration of westerlies, global warming, and human activities. Integrated management and rational utilization of water resources are therefore crucial for ecological protection and sustainable development in the future.
Article
Environmental Sciences
Emma Conrad-Rooney, Jonathan Gewirtzman, Yanni Pappas, Valerie J. Pasquarella, Lucy R. Hutyra, Pamela H. Templer
Summary: Compared to rural areas, there is a lack of understanding of wet atmospheric deposition trends in urban and suburban areas of the U.S. This study examined long-term trends in atmospheric deposition of various substances and found differences in deposition rates between urban and rural sites, suggesting the need for ongoing monitoring.
ATMOSPHERIC ENVIRONMENT
(2023)
Article
Environmental Sciences
Satomi Ban, Kazuhide Matsuda, Tsuyoshi Ohizumi
Summary: In cooperation with the Acid Deposition Monitoring Network in East Asia (EANET), we developed a method to estimate nitrogen dry deposition on forests in East Asia. The method utilizes monthly meteorological data to calculate deposition velocities and assess nitrogen load. The study found that forest ecosystems in mid-latitude and southeast areas of East Asia face high risks of nitrogen load.
WATER AIR AND SOIL POLLUTION
(2022)
Article
Environmental Sciences
Yvonne Y. Y. Yau, Naomi Geeraert, David M. Baker, Benoit Thibodeau
Summary: This study investigates the impact of atmospheric nitrogen deposition on the nitrogen cycle in Hong Kong. The results show that seasonal variations and changes in sources contribute to the variation in nitrate concentration. The estimated amount of nitrate and ammonium deposited from the atmosphere is comparable to the discharge from sewage and groundwater, indicating its significant impact on water quality.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Engineering, Civil
Junqiang Yao, Yaning Chen, Jing Chen, Yong Zhao, Dilinuer Tuoliewubieke, Jiangang Li, Lianmei Yang, Weiyi Mao
Summary: Studies on precipitation changes in Central Asia show an increasing trend in total and extreme precipitation indices, especially in the wetter sub-regions. Model simulations suggest a robust increase in total precipitation, extreme precipitation, and consecutive dry days in the region under different climate scenarios.
JOURNAL OF HYDROLOGY
(2021)
Article
Environmental Sciences
David B. Kelleghan, Enda T. Hayes, Mark Everard, Padraig Keating, Anna Lesniak-Podsiadlo, Thomas P. Curran
Summary: With increasing global demand for food, the agriculture sector is at risk of intensification and expansion, potentially accelerating negative impacts on biodiversity. Nitrogen deposition, alongside changing land use and climate, is identified as a leading cause of global biodiversity decline. Strict protection measures are required at Natura 2000 sites across Europe to ensure designated features achieve favorable conservation status.
ATMOSPHERIC ENVIRONMENT
(2021)
Article
Environmental Sciences
Yongxiao Ge, Na Wu, Jilili Abuduwaili, Gulnura Issanova
Summary: Arid central Asia is characterized by a dry climate with little precipitation and frequent dust storms. The Tianshan Mountains in the heart of this region play a vital role as a water resource supply zone and ecological barrier. The study conducted an assessment of aerosols over different regions of the Tianshan Mountains using CALIPSO data and HYSPLIT model, and found that dust and polluted dust were the dominant aerosol subtypes. The primary sources of these aerosols were identified as the Karakum Desert, Kyzylkun Desert, Moyunkum Desert, and Gurbantunggut Desert.
ATMOSPHERIC ENVIRONMENT
(2023)
Article
Environmental Sciences
Dara Salcedo, Harry Alvarez-Ospina, Sara E. Olivares-Salazar, Rafael N. Linan-Abanto, Telma Castro
Summary: The study investigates the concentration and chemical composition of particulate matter in the Metropolitan Area of Queretaro, a semi-arid region in central Mexico. It reveals that the seasonal concentrations are mainly influenced by meteorological factors and that secondary components constitute the largest fraction of PM2.5. The research also highlights the significant role of regional processing in the formation of secondary aerosols and the occurrence of local oxidation reactions, which mostly take place at night.
Article
Meteorology & Atmospheric Sciences
Tingting Xie, Wei Huang, Shiqiao Chang, Fei Zheng, Jianhui Chen, Jie Chen, Fahu Chen
Summary: This study investigates the moisture sources of extreme precipitation events in arid Central Asia (ACA), showing that both Northern and Southern ACA are influenced by multiple sources of water vapor, with anomalous moisture from the North Atlantic and Arctic Ocean playing a key role in precipitation development. Additionally, atmospheric pressure anomalies are also crucial in determining precipitation patterns in ACA.
INTERNATIONAL JOURNAL OF CLIMATOLOGY
(2021)
Article
Environmental Sciences
Hung-Yu Chen, Li-Min Huang, Tung-Yuan Ho, Kuo-Ping Chiang, Wen-Chen Chou
Summary: The study explores nitrogen (N) and phosphorus (P) imbalances in the atmosphere of East Asia, finding that the N/P ratio is mainly influenced by seasonal wind directions and rainfall. Mainland China in East Asia typically has a higher G/M ratio. The study also categorizes global N and P fluxes into four distribution patterns.
ATMOSPHERIC ENVIRONMENT
(2021)
Article
Microbiology
Yang Hu, Mo Chen, Zailei Yang, Mengfei Cong, Xinping Zhu, Hongtao Jia
Summary: This study examined the effects of short-term nitrogen application on soil microbial community in an arid alpine wetland using high-throughput sequencing technology. The results showed that nitrogen application significantly changed the structure of soil bacterial community, but had little effect on fungal community. Additionally, nitrogen application decreased the potential function of nitrogen and sulfur cycling in bacterial community.
FRONTIERS IN MICROBIOLOGY
(2022)
Article
Geography, Physical
Dongliang Zhang, Zhaodong Feng, Chenjie Su, Kaihui Li, Xuexi Ma, Long Ma, Xinghua Zhao
Summary: The topography of the Tianshan Mountains and the Pamir Plateau strongly influences the seasonality of precipitation in Central Asia. Western Central Asia receives more precipitation during the cold season (October-April), while eastern Central Asia receives more precipitation during the warm season (May-September). The precipitation patterns between western and eastern Central Asia are completely opposite at seasonal, decadal, and centennial scales, but the pattern contrasts for millennial or longer time scales are still unknown.
Article
Physics, Multidisciplinary
Wen-Xiao Wang, Kaihui Li, Xiaoshan Dong, Hao Xie, Jinglan Qiu, Chunqiang Xu, Kai Liu, Juntao Song, Ying Liu, Ke-Ke Bai, Yi-Wen Wei, Xiaofeng Xu
Summary: This study systematically investigates atomic defects in Nickel ditelluride (NiTe2) and identifies five distinct types of defects, with metal intercalation defect being the most predominant one. The study also reveals that the topological surface states of NiTe2 are surprisingly robust against these atomic defects.
Article
Energy & Fuels
Dongya Han, Kaihui Li
Summary: Thermal stress can greatly alter the microstructure of rocks, leading to changes in their physical and mechanical properties. In this study, marble samples were heated to different temperatures and subjected to monotonic and cyclic tension tests to investigate the thermal effects on their physical properties and tensile behaviors. The results show that thermal damage weakens the marble samples, causing a decrease in their tensile strength and P-wave velocity, as well as an increase in porosity. The changing trends of Young's modulus and failure strain with temperature are complex and vary, possibly due to different deformation types. Nonlinearity is a prominent feature in the stress-strain curves, especially when the samples are heated at higher temperatures. Even under low stress levels, permanent damages are observed, indicating hysteresis in the stress-strain curves obtained from cyclic tension tests. A transition from nonlinear elastic deformation to plastic deformation occurs at approximately 300-400°C. A crack density-based constitutive model is proposed to describe the nonlinear elastic deformation (25-300°C), while a modified Voce exponential function is recommended for capturing the tensile stress-strain relationships during plastic deformation (400-700°C).
Article
Engineering, Mechanical
Mengxiang Wang, Jiangteng Li, Han Tan, Ju Wang, Zhanming Shi, Kaihui Li
Summary: This paper analyzed the fatigue characteristics of red sandstone after heat treatment from the perspectives of stress-strain curve, deformation, energy, and damage. In addition, the thermal damage mechanism was discussed through X-ray diffraction and thermogravimetric-differential scanning calorimetry synchronous analysis tests. The results showed that 400 degrees C was the critical temperature, below which brittleness, failure stress, and stiffness of the specimen increased, otherwise, they decreased. Mineral decomposition, dehydration, and crystal expansion occurred during the heat treatment process. The thermal damage mechanism of red sandstone can be explained by a competitive mechanism of strengthening and weakening effects.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Agriculture, Dairy & Animal Science
Fengwei Zhang, Chong Wang, Haiyue Xu, Xiaoting Xia, Xiaoyu Luo, Kaihui Li, Jianlin Han, Chuzhao Lei, Ningbo Chen, Xiangpeng Yue
Summary: The genetic basis of the white coat phenotype in the Tianzhu White yak breed was investigated using population genomics analysis and genome-wide association study. The results revealed the presence of KIT-linked Cs alleles in all-white yak, with additional duplications compared to colour-sidedness cattle. Interestingly, the Cs alleles associated with the white coat phenotype were found to have introgressed from taurine cattle, unveiling the shared genetic control of this trait in closely related bovine species.
JOURNAL OF ANIMAL BREEDING AND GENETICS
(2023)
Article
Environmental Sciences
Haining Li, Yanming Gong, Fei Fang, Kaihui Li, Yanyan Liu
Summary: This study investigated the changes in invasive plant population characteristics under different nutrient addition treatments using the native invasive species Pedicularis kansuensis. The results showed that nitrogen addition effectively inhibited the growth and development of P. kansuensis, while phosphorus addition had no significant effect on its invasive characteristics.
Article
Green & Sustainable Science & Technology
Xiangqi Hu, Mingliang Chen, Bo Hu, Guangzhen Du, Kaihui Li
Summary: Since 2020, the demand and consumption of personal protective equipment, such as masks, have increased dramatically worldwide due to the global spread of major respiratory infectious diseases like COVID-19. This study evaluates the mechanical properties of mask-chip-reinforced soil through various compression tests on reshaped sandy soil samples mixed with different contents of mask chips. The results show that the mechanical properties of the soil can be improved by the proper addition of mask chips, enhancing failure strength and delaying soil failure. The stress path and mask chip content significantly affect the strength and stiffness, and the mechanical properties of the soil do not necessarily improve with increasing mask chip content.
Article
Chemistry, Physical
Junyuan Xu, Lihua Zhu, Huan Zhang, Xin Deng, Kaihui Li, Bing Hui Chen
Summary: The Pd-based supported nanocatalysts (Pd/SiO2) with various Pd contents showed high conversion and selectivity in phenol selective hydrogenation to cyclohexanone. The Pd/SiO2-2 catalyst exhibited the highest conversion of 80.6%, selectivity of 92.1%, and turnover frequency of 1106.1 h-1. The excellent activity was attributed to highly dispersed Pd nanoparticles on silica with high surface area. The Pd/SiO2 catalysts demonstrated good catalytic behaviors and stability in the selective hydrogenation of phenol.
MOLECULAR CATALYSIS
(2023)
Article
Engineering, Civil
Fei Wang, Peng Zhang, Kaihui Li, Cong Wang, Pengfei Cui
Summary: The existence of joints at key positions significantly affects the stress distribution and thus the strength and stability of tunnels. This study conducted uniaxial compression tests on samples containing joints to investigate the influence of key joint parameters on the mechanical and fracture characteristics of tunnels. The experimental results showed that the compressive strength of samples reached the highest and lowest values at joint inclination angles of 0° and 60°, respectively, and the strength was negatively correlated with joint length. Interestingly, certain key joints improved the strength of single-holed samples. Strain bands and cracks mainly developed around the joint and tunnel, which was well explained by the stress distribution results obtained with COMSOL software. Numerical results indicated that increasing joint inclination led to higher tensile stress at the upper endpoint of the circular hole and slightly increased compressive stress at the left and right endpoints. The failure modes of samples with different joint inclinations could be classified into three categories: center-symmetric failure (0° and 90°), through-joint failure (30° and 45°), and axisymmetric failure (60°). The box fractal dimension of surface cracks at peak stress was closely related to the failure mode, and samples with the same failure mode exhibited a positive correlation between box fractal dimension and peak stress.
ARCHIVES OF CIVIL AND MECHANICAL ENGINEERING
(2023)
Article
Chemistry, Physical
Kaihui Li, Junyuan Xu, Huan Zhang, Lihua Zhu
Summary: In this study, Pd/WO3 catalysts with different Pd contents were prepared via sodium borohydride liquid phase reduction and used for phenol selective hydrogenation. The Pd/WO3-2 catalyst showed excellent catalytic performance with 92.9% conversion, 84.4% selectivity, and high TOF (349.1 h(-1)) under the reaction conditions.
Article
Geosciences, Multidisciplinary
Yang Hu, Guangling Yu, Jianqin Zhou, Kaihui Li, Mo Chen, Maidinuer Abulaizi, Mengfei Cong, Zailei Yang, Xinping Zhu, Hongtao Jia
Summary: Grazing and reclamation have significant impacts on soil organic carbon (SOC) stability in alpine steppes. This study investigated the effects of grazing and reclamation on soil aggregate distributions, SOC fractions, microbial community, and their contributions to SOC stability. The findings highlight the importance of soil bacterial network patterns and community assembly in regulating SOC stability in response to human activities.
Article
Engineering, Mechanical
Zhanming Shi, Jiangteng Li, Mengxiang Wang, Han Tan, Hang Lin, Kaihui Li
Summary: This study investigates the influence of temperature on the fracture behavior and morphology of granite after thermal shock. The results show that temperature can change the fracture mode of rocks and have a softening effect on rocks. High temperatures can convert rocks from brittle to ductile failure and even change the fracture mode from pure mode III to mixed mode I/III fracture.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Green & Sustainable Science & Technology
Bo Hu, Xiangqi Hu, Chenggeng Lin, Guangzhen Du, Tianxing Ma, Kaihui Li
Summary: The combined effects of thermal and cyclic loading have complex mechanical effects on engineering rock masses. Understanding the physical and mechanical properties of these rock masses is crucial for improving the stability and sustainability of structures built on them. Experimental results show that thermal treatment reduces the density and P-wave velocity of the rock specimens and increases their degree of damage. Thermal treatment also generally decreases the compressive strength and elastic modulus of the specimens, while thermal hardening occurs within the temperature range of 200-400°C. The specimens' dilatancy characteristics change with the treatment temperature, and they are more prone to shear dilation under external loading. Additionally, the failure mode of the specimens transitions from brittle to ductile failure as the treatment temperature increases. The combination of thermal treatment and cyclic loading causes the rock fragments to become looser and finer following specimen failure.
Article
Green & Sustainable Science & Technology
Qingxiong Zhao, Kaihui Li, Ping Cao, Yinzhu Liu, Yongkang Pang, Jingshuo Liu
Summary: This study investigates the stability of the Liuyang River embankment in the crossing tunnel section of Changsha Metro's Line 6. A calculation model of the subway tunnel crossing the embankment under the coupling of fluids and solids was established using numerical simulation and field monitoring methods. The research analyzes the process of tunnel crossing, spatial displacement, and plastic strain variation in different geological layers. The results show that the east bank experiences greater deformation than the west bank, and crossing the west bank is the riskier stage. The monitored deformation data align well with the simulated settlement results.
Article
Computer Science, Information Systems
Kaihui Li, Yuan Zhuang, Jinling Lai, Yunhui Zeng
Summary: This paper presents an improved small target pedestrian detection algorithm named PF_YOLOv4 based on the YOLOv4 algorithm. The algorithm makes three improvements on the basis of YOLOv4: adding a soft thresholding module to the residual structure of the backbone network to perform noise reduction, replacing traditional convolution with depthwise separable convolution to reduce model parameters, and adding the Convolutional Block Attention Module (CBAM) to enhance network feature expression. Experimental results show that the PF_YOLOv4 algorithm outperforms most state-of-the-art algorithms in detecting small target pedestrians, achieving higher mAP and slightly faster detection speed compared to YOLOv4.
