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Mapping impervious surfaces with a hierarchical spectral mixture analysis incorporating endmember spatial distribution

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Geo-Spatial Information Science 2022年第4期25卷 550-567页

作者： Zhenfeng shao Yuan Zhang cheng Zhang Xiao Huang Tao cheng State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhanChina Department of Geosciences University of ArkansasFayettevilleARUSA

Impervious surface mapping is essential for urban environmental *** Mixture Analysis(SMA)and its extensions are widely employed in impervious surface estimation from medium-resolution *** SMA,inappropriate endmember combinations and inadequate endmember classes have been recognized as the primary reasons for estimation ***,the spectral-only SMA,without considering urban spatial distribution,fails to consider spectral variability in an adequate *** lack of endmember class diversity and their spatial variations lead to over/*** mitigate these issues,this study integrates a hierarchical strategy and spatially varied endmember spectra to map impervious surface abundance,taking Wuhan and Wuzhou as two study ***,the piecewise convex multiple-model endmember detection algorithm is applied to automatically hierarch-ize images into three regions,and distinct endmember combinations are independently developed in each ***,spatially varied endmember spectra are synthesized through neighboring spectra using the distance-based *** analysis indicates that the proposed method achieves better performance than Hierarchical SMA and Fixed Four-endmembers SMA in terms of MAE,SE,and *** analysis suggests that the hierarch-ical strategy can expand endmember class types and considerably improve the performance for the study areas in general,specifically in less developed ***,we find that spatially varied endmember spectra facilitate the reduction of heterogeneous surface material variations and achieve the improved performance in developed areas.

关键词： Impervious surface Spectral Mixture Analysis(SMA) hierarchical strategy endmember class spatially varied endmember spectra

Electrochemical Probe of Hydroxylation of 4-Nitro-phenol by Cytochrome C with Hydrogen Peroxide

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Chemical Research in Chinese Universities 1998年第2期14卷 45-51页

作者： ZHU Yi-min WANG Jin-cheng LI Jing-hong DONG shao-jun BU Feng-quan Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022 Norma n Bethune Univer sity of Medica l Science Cha ngchun130023

BU Fengquan(Norman Bethune University of Medical Science, Changchun, 130023)(Received Dec. 2, 1996) The reaction of hydrogen peroxide with cytochrome c makes them coupled to lead to the hydroxylation of 4-nitrophenol. In situ electrochemical probe was used to detect the hydroxylation of 4-nitrophenol, which can avoid the tedious extraction procedure, the loss of the active species and the interference of some colored substances in the detection of 4-nitrocatechol by spectroscopic method. The hydroxyl radical scavengers mannitol and sodium benzoate did not eliminate hydroxylation, but the inhibitory effect of uric acid on the hydroxylation lead to the formation of the ferryl species of the protein during the reaction. These studies suggest that the electrochemical probe might efficiently detect the trace 4-nitrocatechol from the onset of the hydroxylation reaction and thus provides a more sensitive tool.

关键词： Hydrogen peroxide Hydroxylation of 4-nitrophenol Cytochrome c

Lateral epitaxial grown of two-dimensional halide perovskite heterostructures

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Rare Metals 2020年第8期39卷 863-864页

作者： cheng-Rui shao Wei Hu School of Physics and Electronics Hunan UniversityChangsha 410083China

In last decade,the halide perovskite materials have been widely explored all over the world for their excellent optoelectronic *** perovskite solar cells in particular are reshaping the landscape of ***,the perovskite... 详细信息

关键词： properties. perovskite landscape

铜锶二元掺杂硅酸钙涂层改性钛合金的促成骨和抗菌效应

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中国组织工程研究 2025年第22期29卷 4639-4646页

作者：程新奇邵龙辉沈华侨刘宏伟南京医科大学附属常州第二人民医院骨科南京医科大学常州医学中心江苏省常州市213003 大连医科大学研究生院辽宁省大连市116044

背景:钛合金作为骨科植入物时缺乏生物活性,可导致种植体松动和假体周围感染,因此,研究一种兼顾促成骨和抗感染复合功能的钛合金表面改性方法具有重要意义。目的:研究铜、锶二元掺杂硅酸钙复合涂层改性钛合金的理化性质,评估其促成骨和... 详细信息

背景:钛合金作为骨科植入物时缺乏生物活性,可导致种植体松动和假体周围感染,因此,研究一种兼顾促成骨和抗感染复合功能的钛合金表面改性方法具有重要意义。目的:研究铜、锶二元掺杂硅酸钙复合涂层改性钛合金的理化性质,评估其促成骨和抗菌方面的潜能。方法:采用球磨、造粒方法制备含有氧化铜、氧化锶及硅酸钙的复合粉末,采用大气等离子喷涂技术在钛合金(Ti6Al4V)表面制备铜锶二元掺杂硅酸钙复合涂层,对复合涂层进行表征。将钛合金浸提液、硅酸钙涂层改性钛合金浸提液、铜掺杂硅酸钙复合涂层改性钛合金浸提液、铜锶二元掺杂硅酸钙复合涂层改性钛合金浸提液分别与MC3T3-E1细胞共培养,检测材料的生物安全性与促成骨性能。将金黄色葡萄球菌(或大肠埃希菌)分别与钛合金、硅酸钙涂层改性钛合金、铜掺杂硅酸钙复合涂层改性钛合金、铜锶二元掺杂硅酸钙复合涂层改性钛合金共培养,扫描电镜、平板计数法检测材料的体外抗菌性能。结果与结论:(1)扫描电子显微镜下可见铜锶二元掺杂硅酸钙复合涂层粗糙表面存在大量的纳米结构,该复合涂层成功喷涂在钛合金表面,在体外可缓释Sr^(2+)和Cu^(2+),并且Sr^(2+)的释放浓度大于Cu^(2+);(2)CCK-8和细胞活死染色结果显示,铜掺杂硅酸钙复合涂层改性钛合金具有一定的细胞毒性,硅酸钙涂层与铜锶二元掺杂硅酸钙复合涂层改性钛合金具有良好的生物相容性;碱性磷酸酶与茜素红染色结果显示,相较于钛合金、硅酸钙涂层改性钛合金,铜锶二元掺杂硅酸钙复合涂层改性钛合金表现出更优的促成骨性能;(3)扫描电镜观察、细菌涂布和细菌计数法结果表明,相较于钛合金、硅酸钙涂层改性钛合金,铜掺杂硅酸钙复合涂层与铜锶二元掺杂硅酸钙复合涂层改性钛合金能有效抑制金黄色葡萄球菌和大肠埃希菌的生长,表现出抗菌潜能;(4)结果表明,铜锶二元掺杂硅酸钙复合涂层改性钛片具备良好的生物相容性、促成骨性能与抗菌性能。

关键词：钛合金等离子体喷涂复合涂层氧化铜氧化锶硅酸钙成骨金黄色葡萄球菌大肠埃希菌

Effects of the combined application of organic and chemical nitrogen fertilizer on soil aggregate carbon and nitrogen:A 30-year study

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Journal of Integrative Agriculture 2023年第11期22卷 3517-3534页

作者： BAI Jin-shun ZHANG Shui-qing HUANG shao-min XU Xin-peng ZHAO Shi-cheng QIU shao-jun HE Ping ZHOU Wei State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081P.R.China Key Laboratory of Plant Nutrition and Fertilizers Ministry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081P.R.China Institute of Plant Nutrition and Resource Environment Henan Academy of Agricultural SciencesZhengzhou 450002P.R.China

To understand the long-term effects of combined organic and chemical nitrogen fertilization on soil organic C(SOC) and total N(TN), we conducted a 30-year field experiment with a wheat–maize rotation system on the Huang-HuaiHai Plain during 1990–2019. The experimental treatments consisted of five fertilizer regimes: no fertilizer(control), chemical fertilizer only(NPK), chemical fertilizer with straw(NPKS), chemical fertilizer with manure(NPKM), and 1.5 times the rate of NPKM(1.5NPKM). The NPK, NPKS, and NPKM treatments had equal N inputs. The crop yields were measured over the whole experimental duration. Soil samples were collected from the topsoil(0–10 and 10–20 cm) and subsoil(20–40 cm) layers for assessing soil aggregates and taking SOC and TN measurements. Compared with the NPK treatment, the SOC and TN contents increased significantly in both the topsoil(24.1–44.4% for SOC and 22.8–47.7% for TN) and subsoil layers(22.0–47.9% for SOC and 19.8–41.8% for TN) for the organically amended treatments(NPKS, NPKM and 1.5NPKM) after 30 years, while no significant differences were found for the average annual crop yields over the 30 years of the experiment. The 0–10 cm layer of the NPKS treatment and the 20–40 cm layer of the NPKM treatment had significantly higher macroaggregate fraction mass proportions(19.8 and 27.0%) than the NPK treatment. However, the 0–10 and 20–40 cm layers of the 1.5NPKM treatment had significantly lower macroaggregate fraction mass proportions(–19.2 and –29.1%) than the control. The analysis showed that the higher SOC and TN in the soil of organically amended treatments compared to the NPK treatment were related to the increases in SOC and TN protected in the stable fractions(i.e., free microaggregates and microaggregates within macroaggregates), in which the contributions of the stable fractions were 81.1–91.7% of the increase in SOC and 83.3–94.0% of the increase in TN, respectively. The relationships between average C inputs and both stable

关键词： soil aggregate fractions soil organic matter manure application straw return C:N ratio

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乡村振兴视角下朱德“三农”思想探析

齐齐哈尔大学学报(哲学社会科学版) 2025年第1期 54-57页

作者：成靖邵彦涛华中师范大学马克思主义学院湖北武汉430079

新中国成立后,朱德充分认识到农业在社会主义建设中的基础地位,在深入各地调查研究的过程中形成了一套关于“三农”工作较为全面和系统的思想。他主张加强水利、交通等基础设施建设,要求国家从财政、税收、科技等方面支持农业农村的发展... 详细信息

新中国成立后,朱德充分认识到农业在社会主义建设中的基础地位,在深入各地调查研究的过程中形成了一套关于“三农”工作较为全面和系统的思想。他主张加强水利、交通等基础设施建设,要求国家从财政、税收、科技等方面支持农业农村的发展,鼓励各地根据资源禀赋制定农业发展规划,强调基层党组织的建设等,内容涉及农业基础设施建设、产业规划、基层党组织建设、政策保障等多个方面。朱德针对“三农”工作提出的诸多建议,不仅在当时发挥了重要的作用,更成为社会主义建设时期我党积累的宝贵经验、回顾朱德“三农”思想,对实施我国乡村振兴战略具有重要的借鉴意义。

关键词：朱德三农思想乡村振兴战略

Dynamic changes of spontaneous brain activity in patients after LASIK:a resting-state fMRI study

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International Journal of Ophthalmology(English edition) 2025年第3期18卷 487-495页

作者： Hui Zhang Zi-Song Xu Jin-Yu Hu Zhen-Zhe Liu Lei Zhong Liang-Qi He cheng Chen Xiao-Yu Wang Hong Wei Yan-Mei Zeng Qian Ling Xu Chen Yi-Xin Wang Yi shao Nanchang Bright Eye Hospital Nanchang 330000Jiangxi ProvinceChina Department of Ophthalmology the First Affiliated HospitalJiangxi Medical CollegeNanchang UniversityNanchang 330006Jiangxi ProvinceChina Department of Ophthalmology Shanghai General HospitalShanghai Jiao Tong University School of Medicine/National Clinical Research Center for Eye DiseasesShanghai Key Laboratory of Ocular Fundus DiseasesShanghai Engineering Center for Visual Science and PhotomedicineShanghai Engineering Center for Precise Diagnosis and Treatment of Eye DiseasesShanghai 200080China Ophthalmology Centre of Maastricht University Maastricht 6200MSLimburg Provinciethe Netherlands School of Optometry and Vision Science Cardiff UniversityCardiffCF244HQWalesUK

AIM:To investigate changes in local brain activity after laser assisted in situ keratomileusis(LASIK)in myopia patients,and further explore whether post-LASIK(POL)patients and healthy controls(HCs)can be distinguished by differences in dynamic amplitude of low-frequency fluctuations(dALFF)in specific brain ***:The resting-state functional magnetic resonance imaging(rs-fMRI)data were collected from 15 myopic patients who underwent LASIK and 15 matched healthy *** method was selected to calculate the corresponding dALFF values of each participant,to compare dALFF between the groups and to determine whether dALFF distinguishes reliably between myopic patients after LASIK and HCs using the linear support vector machine(SVM)permutation test(5000 repetitions).RESULTS:dALFF was lower in POL than in HCs at the right precentral gyrus and right *** accuracy of the SVM was 89.1%(P<0.001).CONCLUSION:The activity of spontaneous neurons in the right precentral gyrus and right insula of myopic patients change significantly after *** can correctly classify POL patients and HCs based on dALFF differences.

关键词： laser assisted in situ keratomileusis resting-state functional magnetic resonance imaging dynamic brain activity amplitude of low-frequency fluctuations support vector machine

Experimental investigation on the characteristics of molten lead–bismuth non-eutectic alloy fragmentation in water

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Nuclear Science and Techniques 2022年第9期33卷 59-79页

作者： shao-Jie Tan Yu-Bao Zhong Hui cheng Song-Bai cheng Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China

To study the interaction between molten noneutectic alloys and subcooled water during severe nuclear accidents,an experimental investigation was carried out by injecting molten lead–bismuth non-eutectic alloy(LBNE,70%Pb-30%Bi)into the water in a free-fall style using the visualized thermo-hydraulic characteristics in melt coolant interaction(VTMCI)*** effects of various experimental parameters,including water temperature,melt temperature,melt penetration velocity,and water depth,on the molten LBNE jet fragmentation characteristics were *** research shows that compared with lead–bismuth eutectic,larger fragments,less spherical fragments,and more porous debris beds are generated for *** water or melt temperatures facilitate molten LBNE fragmentation,resulting in higher debris bed sphericity and lower debris bed porosity.A higher melt temperature leads to smaller fragment sizes,except that a cake-like debris bed is formed for very high alloy superheat and very low water *** approximate spherical particles were generated in the film boiling zone than in the thermal interaction *** size decreases with an increase in the melt penetration velocity,but the debris bed porosity and sphericity variation was not *** effect of water depth on molten LBNE fragmentation behavior was not obvious under the current experimental *** with other fragmentation theories,the Weber number theory better predicted the fragment volume mean *** addition,a melt-jet behavior mode diagram that describes the competition between the hydrodynamic and thermal interactions and diagrams of debris bed porosity and sphericity that show the influence of thermal factors were analyzed in this study.

关键词： Fuel-coolant interaction Coolant-coolant interaction Debris bed Lead-bismuth non-eutectic alloy-water interaction Fragmentation behavior

Robust stability analysis of switched uncertain systems with multiple time-varying delays and actuator failures

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控制理论与应用（英文版） 2011年第2期9卷 267-272页

作者： Wang, Limin shao, cheng Institute of Advanced Control Technology Dalian University of Technology Dalian Liaoning 116024 China College of Sciences Liaoning Shihua University Fushun Liaoning 113001 China

In this paper,the robust stability issue of switched uncertain multidelay systems resulting from actuator failures is *** on the average dwell time approach,a set of suitable switching signals is designed by using the total activation time ratio between the stable subsystem and the unstable *** is first proven that the resulting closed-loop system is robustly exponentially stable for some allowable upper bound of delays if the nominal system with zero delay is exponentially stable under these switching ***,the maximal upper bound of delays can be obtained from the linear matrix *** last,the effectiveness of the proposed method is demonstrated by a simulation example.

关键词： Robustly exponential stability Actuator failures Average dwell time Switched systems Linear matrix inequalities Multiple time-varying delays