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Spatial variation and soil nitrogen potential hotspots in a mixed land cover catchment on the Chinese Loess Plateau

Journal of Mountain Science 2019年第6期16卷 1353-1366页

作者： YU Yun-long JIN Zhao LIN Henry WANG Yun-qiang ZHAO Ya-li chu guang-chen ZHANG Jing SONG Yi ZHENG Han State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China University of Chinese Academy of Sciences Beijing 100049China CAS Center for Excellence in Quaternary Science and Global Change Chinese Academy of ScienceXi’an 710061China Department of Ecosystem Science and Management the Pennsylvania State UniversityUniversity ParkPA 16802USA Shaanxi Key Laboratory of Accelerator Mass Spectrometry and Application Xi’an AMS CenterXi’an 710061China Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education School of Environmental Science and EngineeringChang’an UniversityXi’an 710054China

Soil nitrogen(N) is critical to ecosystem services and environmental quality. Hotspots of soil N in areas with high soil moisture have been widely studied, however, their spatial distribution and their linkage with soil N variation have seldom been examined at a catchment scale in areas with low soil water content. We investigated the spatial variation of soil N and its hotspots in a mixed land cover catchment on the Chinese Loess Plateau and used multiple statistical methods to evaluate the effects of the critical environmental factors on soil N variation and potential hotspots. The results demonstrated that land cover, soil moisture, elevation, plan curvature and flow accumulation were the dominant factors affecting the spatial variation of soil nitrate(NN), while land cover and slope aspect were the most important factors impacting the spatial distribution of soil ammonium(AN) and total nitrogen(TN). In the studied catchment, the forestland, gully land and grassland were found to be the potential hotspots of soil NN, AN and TN accumulation, respectively. We concluded that land cover and slope aspect could be proxies to determine the potential hotspots of soil N at the catchment scale. Overall, land cover was the most important factor that resulted in the spatial variations of soil N. The findings may help us to better understand the environmental factors affecting soil N hotspots and their spatial variation at the catchment scale in terrestrial ecosystems.

关键词： Soil biogeochemistry Spatial heterogeneity Multivariate statistical analysis Environmental factors Loess Plateau

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Treadmill exercise in combination with acousto-optic and olfactory stimulation improves cognitive function in APP/PS1 mice through the brain-derived neurotrophic factor-and Cygb-associated signaling pathways

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Neural Regeneration Research 2025年第9期20卷 2706-2726页

作者： Biao Xiao Chaoyang chu Zhicheng Lin Tianyuan Fang Yuyu Zhou chuxia Zhang Jianghui Shan Shiyu chen Liping Li Department of Physiology and Pharmacology Health Science CenterNingbo UniversityNingboZhejiang ProvinceChina Ningbo Key Laboratory of Behavioral Neuroscience Health Science CenterNingbo UniversityNingboZhejiang ProvinceChina Key Laboratory of Addiction Research of Zhejiang Province NingboZhejiang ProvinceChina

A reduction in adult neurogenesis is associated with behavioral abnormalities in patients with Alzheimer's ***,enhancing adult neurogenesis represents a promising therapeutic approach for mitigating disease symptoms and ***,nonpharmacological interventions aimed at inducing adult neurogenesis are currently *** individual non-pharmacological interventions,such as aerobic exercise,acousto-optic stimulation,and olfactory stimulation,have shown limited capacity to improve neurogenesis and cognitive function in patients with Alzheimer's disease,the therapeutic effect of a strategy that combines these interventions has not been fully *** this study,we observed an age-dependent decrease in adult neurogenesis and a concurrent increase in amyloid-beta accumulation in the hippocampus of amyloid precursor protein/presenilin 1 mice aged 2-8 *** deposition became evident at 4 months,while neurogenesis declined by 6 months,further deteriorating as the disease ***,following a 4-week multifactor stimulation protocol,which encompassed treadmill running(46 min/d,10 m/min,6 days per week),40 Hz acousto-optic stimulation(1 hour/day,6 days/week),and olfactory stimulation(1 hour/day,6 days/week),we found a significant increase in the number of newborn cells(5'-bromo-2'-deoxyuridine-positive cells),immature neurons(doublecortin-positive cells),newborn immature neurons(5'-bromo-2'-deoxyuridine-positive/doublecortin-positive cells),and newborn astrocytes(5'-bromo-2'-deoxyuridine-positive/glial fibrillary acidic protein-positive cells).Additionally,the amyloid-beta load in the hippocampus *** findings suggest that multifactor stimulation can enhance adult hippocampal neurogenesis and mitigate amyloid-beta neuropathology in amyloid precursor protein/presenilin 1 ***,cognitive abilities were improved,and depressive symptoms were alleviated in amyloid precursor protein/presenilin 1 mice

关键词： acousto-optic stimulation adult neurogenesis Alzheimer's disease amyloid precursor protein/presenilin 1 mice amyloid-beta deposition brain cell apoptosis cognitive impairment depression-like behavior involuntary treadmill exercise olfactory stimulation serum metabolites

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四甲基吡嗪二溴产物结构的确定

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化学学报 1986年第3期44卷 299-301页

作者：杨楚耀陈光润徐光漪上海第一医学院药学系上海医药工业研究院上海

四甲基吡嗪（1）与NBS在四氯化碳中反应,除得到2-溴甲基-3,5,6-三甲基吡嗪外,还可得到一个二溴化物,经高压液相色谱证明为纯化合物,元素分析符合计算值.1H NMR δ值为2.52（6H,s,2×CH3）,4.40（4H,s,2×CH2）ppm.m/z:294（168.1%）,296... 详细信息

四甲基吡嗪（1）与NBS在四氯化碳中反应,除得到2-溴甲基-3,5,6-三甲基吡嗪外,还可得到一个二溴化物,经高压液相色谱证明为纯化合物,元素分析符合计算值.1H NMR δ值为2.52（6H,s,2×CH3）,4.40（4H,s,2×CH2）ppm.m/z:294（168.1%）,296（85.6）,296（85.2）.从1H NMR的δ值表明为二(

关键词：甲氧甲基计算值二甲基毗嗦四甲基乙醚萃取偶极矩溶剂油石油醚相对丰度基峰元素分析

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Efficient photocatalytic reduction of CO2 to formate by a molecular noble metal-free system

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Science China Chemistry 2025年第1期 152-156页

作者： Lihua Zhang Lingjing chen Huatian Shi Yue Wei Gui chen Tai-chu Lau School of Environment and Civil Engineering Research Center for Eco-environmental Engineering Dongguan University of Technology Department of Chemistry and Institute of Molecular Functional Materials City University of Hong Kong

Reducing CO2to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO2to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO2to formate （HCOO-）.Turnover number （TON） for HCOO-up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole （BIH） as sacrificial reductant in a CO2-saturated NMP/TEA （v/v,3:1） solution under visible light *** potential electrolysis at-1.41 V （***/Ag Cl） in the presence of 12 m M Et3NHBF4also produced HCOO-with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-H]species is the key intermediate for CO2reduction.

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Morphology engineering of ZnO micro/nanostructures under mild conditions for optoelectronic application

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 498-503页

作者： Liang chu Haoyu Shen Hudie Wei Hongyu chen Guoqiang Ma Wensheng Yan Institute of Carbon Neutrality and New Energy&School of Electronics and Information Hangzhou Dianzi UniversityHangzhou 310018China School of Applied Physics and Materials Wuyi UniversityJiangmen 529020China

Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 *** reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,simplicity,and easy ***,ZnO morphology engineering has become desirable through the alteration of minor conditions in the reaction process,particularly at room *** this work,ZnO micro/nanostructures were synthesized in a solution by varying the amounts of the ammonia added at low temperatures(including room temperature).The formation of Zn^(2+)complexes by ammonia in the precursor regulated the reaction rate of the morphology engineering of ZnO,which resulted in various structures,such as nanoparticles,nanosheets,microflowers,and single ***,the obtained ZnO was used in the optoelectronic application of ultraviolet detectors.

关键词： morphology engineering low temperature ZnO nanosheets microflowers ultraviolet detector

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塔里木盆地柯坪地区寒武系玉尔吐斯组沉积环境分析

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石油实验地质 2017年第3期39卷 311-317,326页

作者：陈强路储呈林胡广陈跃黄继文姜海健中国石化油气成藏重点实验室江苏无锡214126 中国石化石油勘探开发研究院无锡石油地质研究所江苏无锡214126 西南石油大学成都610500

塔里木盆地柯坪地区出露的寒武系底部玉尔吐斯组为层状硅质岩—黑色泥页岩—白云岩沉积组合。在露头实测的基础上,通过层序地层、岩石学、成烃生物组合及地球化学研究,剖析其沉积环境,为盆地内部早寒武世早期岩相古地理和烃源岩预测提... 详细信息

塔里木盆地柯坪地区出露的寒武系底部玉尔吐斯组为层状硅质岩—黑色泥页岩—白云岩沉积组合。在露头实测的基础上,通过层序地层、岩石学、成烃生物组合及地球化学研究,剖析其沉积环境,为盆地内部早寒武世早期岩相古地理和烃源岩预测提供依据。玉尔吐斯组下部层状硅质岩与中部黑色泥页岩构成三级层序SQ1,受控于早寒武世早期海侵和上升流作用,准层序为退积式叠置;上部中薄层白云岩与肖尔布拉克组下部白云岩构成另一三级层序SQ2,是海退背景下进积型沉积组合。2个三级层序的沉积环境经历了浅水陆棚—深水陆棚—浅水陆棚的演变,其中SQ1黑色泥页岩段为深水陆棚缺氧环境沉积,是烃源岩发育的有利相带。

关键词：沉积环境玉尔吐斯组寒武系柯坪地区塔里木盆地

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Prediction and optimization of flue pressure in sintering process based on SHAP

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 346-359页

作者： Mingyu Wang Jue Tang Mansheng chu Quan Shi Zhen Zhang School of Metallurgy Northeastern UniversityShenyang 110819China Liaoning Low-Carbon Steelmaking Technology Engineering Research Center Northeastern UniversityShenyang 110819China Engineering Research Center of Frontier Technologies for Low-Carbon Steelmaking(Ministry of Education) Shenyang 110819China

Sinter is the core raw material for blast *** pressure,which is an important state parameter,affects sinter *** this paper,flue pressure prediction and optimization were studied based on the shapley additive explanation(SHAP)to predict the flue pressure and take targeted adjustment ***,the sintering process data were collected and processed.A flue pressure prediction model was then constructed after comparing different feature selection methods and model algorithms using SHAP+extremely random-ized trees(ET).The prediction accuracy of the model within the error range of±0.25 kPa was 92.63%.SHAP analysis was employed to improve the interpretability of the prediction *** effects of various sintering operation parameters on flue pressure,the relation-ship between the numerical range of key operation parameters and flue pressure,the effect of operation parameter combinations on flue pressure,and the prediction process of the flue pressure prediction model on a single sample were analyzed.A flue pressure optimization module was also constructed and analyzed when the prediction satisfied the judgment *** operating parameter combination was then *** flue pressure was increased by 5.87%during the verification process,achieving a good optimization effect.

关键词： sintering process flue pressure shapley additive explanation prediction optimization

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Construction of Normal Bimagic Squares of Order 2u

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Acta Mathematicae Applicatae Sinica 2020年第4期36卷 771-789页

作者： Wen LI Feng-chu PAN guang-zhou chen School of Science Xichang UniversityXichang 615000China School of Environment and Resource Xichang UniversityXichang 615000China Henan Engineering Laboratory for Big Data Statistical Analysis and Optimal Control School of Mathematics and Information ScienceHenan Normal UniversityXinxiang 453007China

An n×n matrix A consisting of nonnegative integers is a general magic square of order n if thesum of elements in each row,column,and main diagonal is the same.A general magic square A of order n iscalled a magic square,denoted by MS(n),if the entries of A are distinct.A magic square A of order n is normalif the entries of A are n^2 consecutive *** A^*d denote the matrix obtained by raising each elementof A to the d-th *** matrix A is a d-multimagic square,dcnoted by MS(n,d),if A^*e is an MS(n)for 1≤e≤*** this paper we investigate the existence of normal bimagic squares of order 2u and prove that thereexists a normal bimagic square of order 2u,where u and 6 are coprime and u≥5.

关键词： magic square bimagic square complementary pair multimagic square Latin square

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山西平朔矿区11~#煤中镓的分布特征及富集因素

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煤炭技术 2014年第11期33卷 82-84页

作者：周建飞王金喜白观累刘帮军褚光琛石杰河北工程大学河北省资源勘测研究重点实验室河北邯郸056038

在对平朔矿区大量地质勘探(钻孔)资料与煤质资料分析的基础上,运用SEM-EDX,X射线衍射,光学显微镜等方法对平朔矿区11#煤样品进行研究。结果表明:该煤层中镓的富集和分布主要受陆源碎屑、沉积环境和地下水作用的影响。

关键词：平朔矿区镓分布特征富集因素勃姆石

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Rhizosphere Aeration Improves Nitrogen Transformation in Soil, and Nitrogen Absorption and Accumulation in Rice Plants

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Rice science 2020年第2期27卷 162-174页

作者： XU chunmei chen Liping chen Song chu guang WANG Danying ZHANG Xiufu China National Rice Research Institute Chinese Academy of Agricultural SciencesHangzhou 310006China

Two rice cultivars(Xiushui 09 and chunyou 84)were used to evaluate the effects of various soil oxygen(O2)conditions on soil nitrogen(N)transformation,absorption and accumulation in rice *** treatments were continuous flooding(CF),continuous flooding and aeration(CFA),and alternate wetting and drying(AWD).The results showed that the AWD and CFA treatments improved soil N transformation,rice growth,and N absorption and *** NO3–content,nitrification activity and ammonia-oxidising bacteria abundance,leaf area,nitrate reductase activity,and N absorption and accumulation in rice all increased in both ***,soil microbial biomass carbon and pH did not significantly change during the whole period of rice *** analysis revealed a significant positive correlation between the nitrification activity and ammonia-oxidising bacteria abundance,and both of them significantly increased as the total N accumulation in rice *** results indicated that improved soil O2 conditions led to changing soil N cycling and contributed to increases in N absorption and accumulation by rice in paddy fields.

关键词： ammonium-nitrogen content nitrate-nitrogen content nitrification activity nitrate reductase activity rhizosphere oxygen condition ammonia-oxidising bacteria abundance rice nitrogen use efficiency

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