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Effects of land use change on the spatiotemporal variability of soil organic carbon in an urban-rural ecotone of Beijing,China

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Journal of Integrative Agriculture 2016年第4期15卷 918-928页

作者： YE Hui-chun huang yuan-fang CHEN Peng-fei huang Wen-jiang ZHANG Shi-wen huangShan-yu HOU Sen Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100094P.R.China Hainan Key Laboratory of Earth Observation Sanya 572029P.R.China College of Resources and Environment China Agricultural UniversityBeijing 100193P.R.China State Key Laboratory of Resources and Environment Information System Institute of Geographic Science and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China College of Earth and Environment Anhui University of Science and TechnologyHuainan 232001P.R.China Institute of Geography University of CologneKoln 50923Germany

Understanding the effects of land use changes on the spatiotemporal variation of soil organic carbon （SOC） can provide guidance for low carbon and sustainable agriculture. In this paper, based on the large-scale datasets of soil surveys in 1982 and 2009 for Pinggu District -- an urban-rural ecotone of Beijing, China, the effects of land use and land use changes on both temporal variation and spatial variation of SOC were analyzed. Results showed that from 1982 to 2009 in Pinggu District, the following land use change mainly occurred： Grain cropland converted to orchard or vegetable land, and grassland converted to forestland. The SOC content decreased in region where the land use type changed to grain cropland （e.g., vegetable land to grain cropland decreased by 0.7 g kg-1; orchard to grain cropland decreased by 0.2 g kg-l）. In contrast, the SOC content increased in region where the land use type changed to either orchard （excluding forestland） or forestland （e.g., grain cropland to orchard and forestland increased by 2.7 and 2.4 g kg-1, respectively; grassland to orchard and forestland increased by 4.8 and 4.9 g kg-1, respectively）. The organic carbon accumulation capacity per unit mass of the soil increased in the following order： grain cropland soil〈vegetable land/grassland soil〈orchard soil〈forestland soil. Therefore, to both secure supply of agricultural products and develop low carbon agriculture in a modern city, orchard has proven to be a good choice for land using.

关键词： land use change soil organic carbon spatiotemporal variability urban-rural ecotone

Self-assembled all-oxides three-phase vertically aligned nanocomposite thin film with multifunctionality

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Nano Research 2024年第9期17卷 8226-8232页

作者： Jijie huang yuan fang Ping Lu Juanjuan Lu Haiyan Wang School of Materials Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China School of Materials Engineering Purdue UniversityWest LafayetteIN 47907USA Sandia National Laboratories AlbuquerqueNew Mexico 87185USA School of Electrical and Computer Engineering Purdue UniversityWest LafayetteIN 47907USA

Multi-phase vertically aligned nanocomposite(MP-VAN)thin films represent a promising avenue for achieving complex multifunctionality,exploring novel interfacial phenomena,and enabling complex metamaterial designs and *** this study,a novel self-assembled all-oxides three-phase VAN system was conceptualized and fabricated utilizing pulsed laser deposition(PLD)with a single composite *** microstructural analysis reveals the presence of three distinct phases:LiNbO_(3),CeO_(2-x),and LiNbCe_(1-x)O_(y)within the MP-VAN ***,ferroelectric,dielectric,optical anisotropy,and magnetic properties were systematically investigated to showcase the multifunctionality inherent in these *** work presents a pioneering approach to designing and realizing MP-VAN systems,and opens up opportunities for tailoring the complex three-dimensional(3D)physical properties and property coupling of VAN films towards diverse device applications.

关键词： thin film three-phase vertically aligned nanocomposite multifunctionality ferroelectricity optical anisotropy

Spatial Interpolation of Soil Texture Using Compositional Kriging and Regression Kriging with Consideration of the Characteristics of Compositional Data and Environment Variables

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Journal of Integrative Agriculture 2013年第9期12卷 1673-1683页

作者： ZHANG Shi-wen SHEN Chong-yang CHEN Xiao-yang YE Hui-chun huang yuan-fang LAI Shuang China Agricultural University/Key Laboratory of Arable Land Conservation (North China) Minstry of Agriculture/Key Laboratory of Agricultural Land Quality MonitoringMinistry of Land and Resources School of Earth and Environment Anhui University of Science and Technology Afforestation Management Office Sichuan Forestry Department

The spatial interpolation for soil texture does not necessarily satisfy the constant sum and nonnegativity constraints. Meanwhile, although numeric and categorical variables have been used as auxiliary variables to improve prediction accuracy of soil attributes such as soil organic matter, they （especially the categorical variables） are rarely used in spatial prediction of soil texture. The objective of our study was to comparing the performance of the methods for spatial prediction of soil texture with consideration of the characteristics of compositional data and auxiliary variables. These methods include the ordinary kriging with the symmetry logratio transform, regression kriging with the symmetry logratio transform, and compositional kriging （CK） approaches. The root mean squared error （RMSE）, the relative improvement value of RMSE and Aitchison＇s distance （DA） were all utilized to assess the accuracy of prediction and the mean squared deviation ratio was used to evaluate the goodness of fit of the theoretical estimate of error. The results showed that the prediction methods utilized in this paper could enable interpolation results of soil texture to satisfy the constant sum and nonnegativity constraints. Prediction accuracy and model fitting effect of the CK approach were better, suggesting that the CK method was more appropriate for predicting soil texture. The CK method is directly interpolated on soil texture, which ensures that it is optimal unbiased estimator. If the environment variables are appropriately selected as auxiliary variables, spatial variability of soil texture can be predicted reasonably and accordingly the predicted results will be satisfied.

关键词： compositional kriging auxiliary variables regression kriging symmetry logratio transform

Spatial distribution prediction and benefits assessment of green manure in the Pinggu District,Beijing,based on the CLUE-S model

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Journal of Integrative Agriculture 2016年第2期15卷 465-474页

作者： ZHANG Li-ping ZHANG Shi-wen ZHOU Zhi-ming HOU Sen huang yuan-fang CAO Wei-dong College of Resources and Environment China Agricultural University/Key Laboratory of Arable Land Conservation(North China)Minstry of Agriculture/Key Laboratory of Agricultural Land Quality MonitoringMinistry of Land and Resources School of Earth and Environment Anhui University of Science and Technology Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences

Green manure use in China has declined rapidly since the 1980 s with the extensive use of chemical *** deterioration of field environments and the demand for green agricultural products have resulted in more attention to green *** intervention and policy-oriented behaviors likely have large impacts on promoting green manure ***,little information is available regarding on where,at what rates,and in which ways（i.e.,intercropping green manure in orchards or rotating green manure in cropland） to develop green manure and what benefits could be gained by incorporating green manure in fields at the county *** paper presents the conversion of land use and its effects at small region extent（CLUE-S） model,which is specifically developed for the simulation of land use changes originally,to predict spatial distribution of green manure in cropland and orchards in 2020 in Pinggu District located in Beijing,*** types of land use for planting or not planting green manure were classified and the future land use dynamics（mainly croplands and orchards） were considered in the *** scenarios were used to predict the spatial distribution of green manure based on data from 2011：The promotion of green manure planting in orchards（scenario 1） and the promotion of simultaneous green manure planting in orchards and croplands（scenario 2）.The predictions were generally accurate based on the receiver operating characteristic（ROC） and Kappa indices,which validated the effectiveness of the CLUE-S model in the *** addition,the spatial distribution of the green manure was acquired,which indicated that green manure mainly located in the orchards of the middle and southern regions of Dahuashan,the western and southern regions of Wangxinzhuang,the middle region of Shandongzhuang,the eastern region of Pinggu and the middle region of Xiagezhuang under scenario *** manure planting under scenario 2 occurred in orchards in the middle re

关键词： CLUE-S model green manure spatial distribution prediction benefits assessment

Competitive assembling strategy to construct carbon nitride homojunctions for boosting photocatalytic performance

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Journal of Materials Science & Technology 2024年第5期172卷 23-32页

作者： Hua-Wei Zhang yuan-yuan Li Bo Li Jing-Hui Shi Tao huang Gui-fang huang Anlian Pan Wangyu Hu Wei-Qing huang School of Physics&Electronic Engineering Zhengzhou University of Light IndustryZhengzhou 450002China Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education&Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices School of Physics and ElectronicsHunan UniversityChangsha 410082China College of Materials Science and Engineering Hunan UniversityChangsha 410082China

Both morphology and composition have a great influence on the properties and functions of materials,however,how to rational modulate both of them to achieve their synergistic effects has been a longstanding ***,we demonstrate a competitive assembling strategy for the construction of metal-free graphite carbon nitride(CN)homojunctions in which morphology and composition can be easily controlled simultaneously by only changing the ratio of assembly raw *** homojunctions are comprised of porous nanotubular S-doped CN(SCN)grafted with CN nanovesicles,which are derived from thermal polycondensation of melamine-thiocyanuric acid(M-T)/melamine-cyanuric acid(M-C)supramolecular hybrid *** unique architecture and component engineering endows the novel SCN-CN homojunction with abundant active sites,enhanced visible trapping ability,and intimate interface *** a result,the synthesized SCN-CN homojunctions demonstrate high photocatalytic activity for hydrogen evolution and pollutant *** developed strategy opens up intriguing opportu-nities for the rational construction of intricate metal-free heterostructures with controllable architecture and interfacial contact for applications in energy-related fields.

关键词： Competitive assembling strategy Supramolecular hybrid blocks Homojunctions Graphite carbon nitride Photocatalytic

Network Pharmacology and Molecular Docking Analysis of the Mechanisms of Combined Radix Bupleuri(Chai-Hu) and Radix Paeoniae Alba(Bai-Shao) Treatment in the Prevention and Treatment of Alzheimer's Disease

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World Journal of Traditional Chinese Medicine 2024年第2期10卷 254-262页

作者： Zhao-Han huang yuan fang Qi Yu Tong Wang College of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijingChina Shanghai Center for Women and Children's Health ShanghaiChina

Objective: Radix Bupleuri and Radix Paeoniae Alba are referred to as Chai-Hu and Bai-Shao, respectively, in Chinese. We used molecular docking and network pharmacological approaches to explore the active components of this Chinese herb combination which is commonly used for treating Alzheimer's disease(AD), the Chai-Hu and Bai-Shao pair(CBP). Materials and Methods: The active compounds and action targets of Chai-Hu and Bai-Shao were identified in the Traditional Chinese Medicine Systems Pharmacology database, and the Therapeutic Target Database, Drug Bank, Gen Cards, Dis Ge NET, and Online Mendelian Inheritance in Man databases were used to identify therapeutic targets in patients with AD. To identify a common target of CBP in the treatment of AD, we used the Metascape tool to perform Gene Ontology function enrichment and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses. In addition, CBP-AD protein–protein interaction(PPI) and herb-component-target networks were created using Cytoscape 3.8.2. Molecular docking was verified using Auto Dock tools. Results: We identified 20 active compounds of CBP, 202 active targets, 1,323 disease targets, and 117 active compound disease intersection targets;the PPI network showed that the top eight key targets were AKT1, interleukin(IL) 6, JUN, MAPK1, tumor necrosis factor, TP53, vascular endothelial growth factor, and epidermal growth factor. These act mainly on the fluid shear stress, atherosclerosis, IL-17, hypoxia-inducible factor-1, and nonalcoholic fatty liver disease pathways, among others, which control immune inflammation, cell proliferation, and apoptosis. Based on molecular docking results, the active components of CBP bind well to its key targets. Conclusion: Our results indicated that CBP was effective for treating AD by reducing the expression of inflammatory factors, promoting cell proliferation and differentiation, and preventing nerve cell death and anti-neuronal cell apoptosis.

关键词： Alzheimer's disease Bai-Shao Chai-Hu molecular docking network pharmacology

On Hamiltonian Property of Cayley Digraphs

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 547-556页

作者： fang DUAN Qiong-xiang huang School of Mathematics Science Xinjiang Normal UniversityUrumqi 830017China College of Mathematics and Systems Science Xinjiang UniversityUrumqi 830017China

Let G be a finite group generated by S and C(G,S) the Cayley digraphs of G with connection set *** this paper,we give some sufficient conditions for the existence of hamiltonian circuit in C(G,S),where G=Zm×H is a semiproduct of Zmby a subgroup H of *** particular,if m is a prime,then the Cayley digraph of G has a hamiltonian circuit unless G=Zm×*** addition,we introduce a new digraph operation,called φ-semiproduct of Γ1by Γ2and denoted by Γ1×Γ_φΓ2,in terms of mapping φ:V(Γ2)→{1,-1}.Furthermore we prove that C(Zm,{a})×_φ C(H,S) is also a Cayley digraph if φ is a homomorphism from H to{1,-1} ≤ Zm~*,which produces some classes of Cayley digraphs that have hamiltonian circuits.

关键词： Cayley digraphs hamiltonian circuit external semidirect product

Discovery potential of the Glashow resonance in an air shower neutrino telescope

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Chinese Physics C 2024年第8期48卷 266-275页

作者： Guo-yuan huang School of Mathematics and Physics China University of GeosciencesWuhan 430074China Max-Planck-Institut für Kernphysik Saupfercheckweg 169117 HeidelbergGermany

The in-ice or in-water Cherenkov neutrino telescope,such as IceCube,has already proved its power in measuring the Glashow resonance by searching for the bump around E_(ν)=6.3PeV arising from the W-boson *** are many proposals for the next few decades for observations of cosmic tau neutrinos with extensive air showers,also known as tau neutrino *** air shower telescope is,in principle,sensitive to the Glashow resonance via the channel W→τν_(τ)followed by the tau decay in the air(e.g.,TAMBO,which has a geometric area of approximately 500km^(2)).Using a thorough numerical analysis,we find that the discovery significance can be up to 90%with a TAMBO-like setup if PeV neutrinos primarily originate from neutron decays,considering the flux parameters measured by IceCube as the *** presence of new physics affecting the neutrino flavor composition can also increase the ***,if ultrahigh-energy neutrinos are dominantly produced from meson decays,it will be statistically difficult for an advanced proposal such as TAMBO to discriminate the Glashow resonance induced byν¯e from the intrinsicντ/ν¯_(τ)*** have identified several limitations for such advanced telescopes,in comparison with the in-ice or in-water telescope,when measuring resonances:(i)a suppressed branching ratio of 11%for the decay W→τν_(τ);(ii)the smearing effect and reduced acceptance because the daughter neutrino takes away(y)∼75%of the energy from the W decay;and(iii)a large attenuation effect for Earth-skimming neutrinos with the resonance.

关键词： Ultrahigh-energy neutrinos Neutrino telescopes Glashow resonance

A New Method for Deriving High-Vertical-Resolution Wind Vector Data from the L-Band Radar Sounding System in China

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Advances in Atmospheric Sciences 2024年第11期41卷 2192-2202页

作者： fang yuan Zijiang ZHOU Jie LIAO National Meteorological Information Center China Meteorological AdministrationBeijing 100081China

High-vertical-resolution radiosonde wind data are highly valuable for describing the dynamics of the meso-and microscale atmosphere. However, the current algorithm used in China's L-band radar sounding system for calculating highvertical-resolution wind vectors excessively smooths the data, resulting in significant underestimation of the calculated kinetic energy of gravity waves compared to similar products from other countries, which greatly limits the effective utilization of the data. To address this issue, this study proposes a novel method to calculate high-vertical-resolution wind vectors that utilizes the elevation angle, azimuth angle, and slant range from L-band radar. In order to obtain wind data with a stable quality, a two-step automatic quality control procedure, including the RMSE-F(root-mean-square error F) test and elemental consistency test are first applied to the slant range data, to eliminate continuous erroneous data caused by unstable signals or radar malfunctions. Then, a wind calculation scheme based on a sliding second-order polynomial fitting is utilized to derive the high-vertical-resolution radiosonde wind vectors. The evaluation results demonstrate that the wind data obtained through the proposed method show a high level of consistency with the high-resolution wind data observed using the Vaisala Global Positioning System and the data observed by the new Beidou Navigation Sounding System. The calculation of the kinetic energy of gravity waves in the recalculated wind data also reaches a level comparable to the Vaisala observations.

关键词： L-band radar sounding system upper air high-vertical-resolution radiosonde wind vectors quality control polynomial fitting