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Effect of Farming Practices on the Variability of Phosphorus Status in Intensively Managed Soils

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Pedosphere 2015年第3期25卷 438-449页

作者： SUN Wei-Xia HUANG Biao QU Ming-Kai TIAN Kang yao li-peng FU Ming-Ming YIN li-Ping Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of Sciences Soil and Fertilizer Technology Extension Center Bureau of Agriculture of Rugao County

Phosphorus(P) in agricultural soils is an important factor for soil quality and environmental protection. Understanding of P and its fractions in soils on a regional scale is imperative for effective management or utilization of P and the improvement of P availability in soils. To study spatial variability and changes of soil P and its fractions as affected by farming practices, soil samples were taken in Rugao County, Jiangsu Province of China, an intensive agricultural area in the Yangtze River Delta region, in years of 1982(n = 1 514), 1997(n = 1 651), and 2002(n = 342). High spatial variabilities of Olsen P and total P(TP) were observed throughout the study area. Loamy Stagnic Anthrosols and clay or loamy Aquic Cambosols had significantly higher concentrations of Olsen P and TP than sandy Ustic Cambosols and Aquic Cambosols. Olsen P and TP were increased from 1982 to 2002. The accumulations of Olsen P and TP in the cultivated soils were likely related to the increased application of P fertilizer, organic input,and soil incorporation of crop residues as well as conversion of soil use. Accumulated soil P was dominantly in labile and semi-labile P fractions. These P fractions may be utilized by future crop production by adjusting management practices, but they also pose a serious threat to nearby water bodies. Future strategies should include decreasing P fertilization in soils and supporting sustainable management. The information from this study can be used to monitor changes in soil fertility and environmental risks so that the use of fertilizers can become more rational.

关键词： agriculture management Olsen phosphorus phosphorus availability phosphorus fractionation total phosphorus

The influence of discharge style on the separation of coarse coal slime by a hindered fluidized bed

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Journal of Coal Science & Engineering(China) 2012年第1期18卷 96-100页

作者： Jie Sha Guang-yuan Xie li-gang Tang yao-li peng Xiu-feng Zhang School of Chemical Engineering and Technology China University of Mining and Technology Xuzhou China State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing China Dadi Engineering Development (Group) Co. Ltd. Tianjin China

Two kinds of liquid distributor, a central discharge or a peripheral discharge, were designed into a hindered fluid- ized bed separator. The beneficiation performance of the fluidized bed was investigated using 0.25-1.00 mm coarse coal slime and the two different distributors. The experimental results show that the heterogeneity of axial particle velocity in the radial direction of the bed can be reduced by a distributor that has a central discharge. The beneficiation performance for this dis- tributor is improved relative to the distributor with the peripheral discharge. This indicates that it is necessary to eliminate or suppress the core-annulus structure within a hindered fluidized bed. Increasing superficial water velocity causes the clean coal ash content, the railings ash content, and the combustible recovery to increase. Additionally, increasing the bed height decreases all of these three indexes. The optimum superficial water velocity and bed height for a 0.25-1.00 mm coal feed were deter- mined to be 3 mm/s and 800 mm, respectively. This work provides a foundation for the scale-up of the bed.

关键词： discharge style coarse coal slime hindered fluidized bed liquid distributor

Broncholithiasis-induced bronchial artery fistula and pulmonary artery fistula in an aged female： a case report

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Chinese Medical Journal 2010年第4期123卷 507-509页

作者： SHANG Yan BAI Chong HUANG Hai-dong DONG Yu-chao HUANG Yi yao Xiao-peng li Qiang Department of Respiratory Medicine Changhai Hospital Second Military Medical University Shanghai 200433 China

Broncholithiasis, a rare disorder of the respiratory system, is usually caused by pulmonary fungal infection and tuberculosis occurring in the early years of its victims. Pulmonary fungal infection and tuberculosis can lead to calcification of the hilar and mediastinal lymph nodes; the calcified lymph nodes erode the nearby bronchi and cause clinical and imaging abnormalities. When the calcified lymph nodes press or invade the bronchial lumens, changing the bronchial lumen shape, stimulating the mucous membrane and eroding the luminal wall, clinical manifestations of penetrating broncholithiasis, such as cough, sputum, hemoptysis, lithoptysis, recurrent pneumonia, peribronchial fistula,

关键词： broncholithiasis clinical manifestations diagnosis treatment

Increase in the variability of terrestrial carbon uptake in response to enhanced future ENSO modulation

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 32-38页

作者： Younong li li Dan Jing peng Qidong Yang Fuqiang Yang Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Key Laboratory of Atmospheric Environment and Processes in the Boundary Layer over the Low-Latitude Plateau Region Department of Atmospheric ScienceYunnan UniversityKunmingChina

El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air *** the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further *** investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 *** results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the *** higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in *** flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through *** occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures.

关键词： Carbon variability ENSO modulation CMIP6 models

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao Yu-Gui peng peng Wu Zong-lin li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

氯盐干湿循环下TRC加固钢筋混凝土柱轴心受压性能

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中国公路学报 2017年第6期30卷 230-238页

作者：尹世平李耀李贺东彭驰艾珊霞中国矿业大学深部岩土力学与地下工程国家重点实验室江苏徐州221008 中国矿业大学江苏省土木工程环境灾变与结构可靠性重点实验室江苏徐州221116 浙江大学高性能建筑结构与材料研究所浙江杭州310058

为进一步探究纤维编织网增强混凝土(TRC)修复加固钢筋混凝土柱在氯盐侵蚀环境下的受压性能,对12根TRC加固钢筋混凝土柱进行轴心受压性能试验研究,分析了不同干湿循环次数(0,60,90和120)、不同持续荷载比(0,0.1,0.2和0.4)、氯盐干湿循环... 详细信息

为进一步探究纤维编织网增强混凝土(TRC)修复加固钢筋混凝土柱在氯盐侵蚀环境下的受压性能,对12根TRC加固钢筋混凝土柱进行轴心受压性能试验研究,分析了不同干湿循环次数(0,60,90和120)、不同持续荷载比(0,0.1,0.2和0.4)、氯盐干湿循环与持续荷载耦合作用以及短切纤维改性高性能混凝土对TRC加固效果的影响。研究结果表明:干湿循环作用后TRC加固柱的极限承载力及变形性能有下降趋势,在干湿循环作用次数达到120次后,TRC加固柱的极限承载力降低6.71%;相比于单一的干湿循环作用,在氯盐干湿循环与持续荷载耦合作用下,TRC加固柱的变形和承载力下降更多;在干湿循环(90次)不变时,持续荷载比的增加会降低TRC的加固效果;干湿循环与持续荷载耦合作用的增加会改变TRC加固柱的破坏形态;使用短切PVA纤维改性高性能混凝土作为TRC基体加固钢筋混凝土柱会使其耐久性能稍有提高;给出了氯盐干湿循环作用下TRC加固RC柱的轴心受压极限承载力简化计算公式,计算值与试验值吻合较好。

关键词：桥梁工程纤维编织网增强混凝土轴心受压承载能力钢筋混凝土柱干湿循环

Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： lin peng Yu Bai Hang li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

lithium-sulfur （li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （liPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes li2S dissolution and nucleation ***,the li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： lithium sulfur batteries

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： peng li Meifeng Cai Shengjun Miao Yuan li Yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin Bai Xiaodong li peng Ai Wanrong Guo Tuo Zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)