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A novel spectral index for mapping blue colour-coated steel roofs(BCCSRs)in urban areas using Sentinel-2 data

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International Journal of Digital Earth 2023年第1期16卷 2862-2884页

作者： Chuanwu zhao Yaozhong pan State Key Laboratory of Remote Sensing Faculty of Geographical ScienceBeijing Normal UniversityBeijingPeople’s Republic of China Key Laboratory of Environmental Change and Natural Disasters of Chinese Ministry of Education Beijing Normal UniversityBeijingPeople’s Republic of China Academy of Plateau Science and Sustainability Qinghai Normal UniversityXiningPeople’s Republic of China Beijing Engineering Research Center for Global Land Remote Sensing Products Faculty of Geographical ScienceBeijing Normal UniversityBeijingPeople’s Republic of China

Blue colour-coated steel roofs(BCCSRs)offer a lightweight and economical option to concrete and other cladding in buildings,but they are also controversial for altering the surface energy budget and water *** spatial information about BCCSRs is crucial for exploring the environmental impacts of man-made ***,existing methods are not always effective due to the variety of BCCSR types and background *** overcome these limitations,we proposed a new index(called BCCSI)based on Sentinel-2 multispectral images to map the commonly used *** typical study areas were chosen worldwide to develop and validate the *** on spectral analysis,we constructed the BCCSl using the blue,red,green,and shortwave infrared 2(SWIR2)bands to highlight the BCCSR while suppressing the background *** with five existing indices,the BCCSl was effective in the visual evaluation,separability analysis and BCCSR ***,the BCCSI achieved similar accuracy to the supervised classifier while avoiding the time-consuming and laborious effort of sample ***,the BCCSl showed its applicability in medium-resolution satellite data,such as Landsat-8 ***,the proposed BCCSI provides a viable scheme for global BCCSR mapping and analysis.

关键词： Blue colour-coated steel roof Large-scale mapping Surface energy budget Sentinel 2 Landsat 8

Hedgehog in the Drosophila testis niche:what does it do there?

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Protein & Cell 2013年第9期4卷 650-655页

作者： zhao Zhan Chenyu pan Yun zhao State Key Laboratory of Cell Biology Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China

Stem cell niche is a specialized microenvironment crucial to *** testis in Drosophila contains two dif-ferent types of stem cells,the germline stem cells and the somatic cyst stem cells that are sustained by their respec-tive niche signals,thus is a good system for studying the interaction between the stem cells and their hosting *** JAK-STAT and BMP pathways are known to play critical roles in the self-renewal of different kinds of stem cells,but the roles of several other pathways have emerged recently in a complex signaling network in the testis *** of independent observations from three research groups have uncovered an important role of Hedgehog(Hh)in the Drosophila testis *** this review,we summarize these recent fi ndings and discuss the interplay between the Hh signaling mechanisms and those of the JAK-STAT and BMP *** also dis-cuss directions for further investigation.

关键词： Drosophila testis stem cell Hedgehog JAK-STAT

Synthetic Two-dimensional Organic Structures

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Chinese Journal of Polymer Science 2018年第4期36卷 425-425,426-444页

作者： Hui Liu Xiao-Nan Kan Chen-Yu Wu Qing-Yan pan Zhi-Bo Li ying-Jie zhao Qingdao University of Science and Technology Qingdao 266042China Centre for Advanced Macromolecular Design School of Chemical EngineeringThe University of New South WalesSydneyNSW2052Australia

Synthetic two-dimensional（2 D） polymers have totally different topology structures compared with traditional linear or branched polymers. The peculiar 2 D structures bring superior properties. Although, from linear to 2 D polymers, the study of these new materials is still in its infancy, they already show potential applications especially in optoelectronics, membranes, energy storage and catalysis, etc. In this review, we summarize the recent progress of the 2 D materials from three respects：（1） Chemistry—different types of polymerization reactions or supramolecular assembly to construct the 2 D networks were described;（2） Preparation methods—surface science, crystal engineering approaches and solution synthesis were introduced;（3） Functionalization and some early applications.

关键词： Two-dimensional structures Interracial synthesis 2D crystal Covalent organic frameworks (COFs) Supramolecular assembly

Evolution of Bond-Order-Wave Phase in One-Dimensional Mott Insulators

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Communications in Theoretical Physics 2006年第5X期46卷 923-928页

作者： HUANG Xiao-Xuan pan Zheng-Quan XU zhao-Xin DAI Jian-Hui ying He-Ping Zhejiang Institute of Modern Physics Zhejiang University Hangzhou 310027 China Department of Physics Zhejiang University Hangzhou 310027 China

In this paper, by using the level spectroscopy method and bosonization theory, we discuss the evolution of the bond-order-wave （BOW） phase in a one-dimensional half-filled extended Hubbard model wlth the on-site Coulomb repulsion U as well as the inter-site Coulomb repulsion V and antiferromagnetic exchange J. After clarifying the generic phase diagrams in three limiting cases with one of the parameters being fixed at zero individually, we find that the BOW phase in the U-V phase diagram is initially enlarged as J increases from zero but is eventually suppressed as J increases further in the strong-coupling regime. A three-dimensional phase diagram is suggested where the BOW phase exists in an extended region separated from the spin-density-wave and charge-density-wave phases.

关键词： bond-order-wave phase Mott insulators one-dimensional extended Hubbard model

Exploring the Novel Genetic Variant of PITX1 Gene and Its Effect on Milk Performance in Dairy Goats

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Journal of Integrative Agriculture 2013年第1期12卷 118-126页

作者： LAN Xian-yong zhao Hai-yu LI Zhuan-jian ZHOU Rui pan Chuan-ying LEI Chu-zhao CHEN Hong College of Animal Science and Technology Northwest A&F University/Shaanxi Key Laboratory of Molecular Biology for Agriculture College of Life Sciences Northwest A&F University

Paired-like homeodomain transcription factor 1 （PITX1） plays an important role in pituitary development by indirectly regulating the expression of the GH and PRL genes, and therefore PITX1 gene is regarded as a potential candidate gene for building the relationship between the gene polymorphism and milk traits. The aim of this study was to explore the novel genetic variant in PITX1 gene and its effect on milk performance in dairy goats. Herein, a novel genetic variation （NW_00314033： g.201GA or IVS1＋41GA） located at nt41 position of the first intron of the goat PITX1 gene was reported at the P1 locus, which can be genotyped by the Msp I PCR-RFLP. In the Msp I PCR-RFLP analyis, the GG variant was a major genotype, and the A variant was a minor allele in Guanzhong dairy goats which was at Hardy-Weinberg disequilibrium （chi-square χ2=140, P0.01）. The establishment of associations between different genotypes and milk performance was performed in the analyzed population. A total of three significant associations of the polymorphism with average milk fat content （%）（P=0.045）, morning milk fat content （%）（P=0.049）, and afternoon milk fat content （%）（P=0.050）, were found, respectively. A significant relationship between the polymorphism and average total solid content （P=0.029） was also detected. This novel single nucleotide polymorphism （SNP） extended the spectrum of genetic variation of the goat PITX1 gene, and its significant association with milk performance would benefit from the application of DNA markers related to improving milk performance through marker-assisted selection （MAS） in dairy goats.

关键词： dairy goat PITX1 gene genetic variant association milk performance

Climatology of Tropical Cyclone Extreme Rainfall over China from 1960 to 2019

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Advances in Atmospheric Sciences 2022年第2期39卷 320-332页

作者： ying LI Dajun zhao National Climate Centre Beijing 100081China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China

Tropical cyclone extreme rainfall(TCER)causes devastating floods and severe damage in China and it is therefore important to determine its long-term climatological distribution for both disaster prevention and operational *** on the tropical cyclone(TC)best-track dataset and TC precipitation data from 1960 to 2019,the spatiotemporal distribution of TCER affecting China is *** show that there were large regional differences in the threshold for TCER in China,decreasing from the southeastern coast to the northwest *** occurred infrequently in northern China but had a high intensity and was highly *** frequency and intensity of TCER showed slightly increasing trends over time and was most likely to occur in August(41.0%).Most of the TC precipitation processes with extreme rainfall lasted for four to six days,with TCER mainly occurring on the third to fourth *** with wide areas showed a northwestward prevailing track and a westward prevailing *** TCs are not always accompanied by extreme precipitation while some weak TCs can lead to very extreme rainfall.A total of 64.7%(35.3%)of the TCER samples occurred when the TC was centered over the land(sea).TCER≥250 mm was located within 3°of the center of the *** the center of the TC was located over the sea(land),the extreme rainfall over land was most likely to appear on its northwestern(northeastern)side with a dispersed(concentrated)*** has unique climatic characteristics relative to the TC precipitation.

关键词： tropical cyclones extreme rainfall threshold track characteristics intensity characteristics

A data-based review on norfloxacin degradation by persulfate-based advanced oxidation processes:Systematic evaluation and mechanisms

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Chinese Chemical Letters 2023年第12期34卷 65-75页

作者： pan Wang Huixuan Zhang Zhuohan Wu Xiao zhao ying Sun Na Duan Zhidan Liu Wen Liu College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083China College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation College of Resources and Environmental SciencesChina Agricultural UniversityBeijing100193China

Persulfate-based advanced oxidation processes(AOPs)have obtained increasing attention due to the generation of sulfate radical(SO_(4)-)with high reactivity for organic contaminants degradation,Numerous activation methods have been used to activate two common persulfates:peroxymonosulfate(PMS)and peroxydisulfate(PDS).However,the comparisons of activation methods and two oxidants in the comprehensive degradation performance of the target contaminant are still ***,taking norfloxacin(NOR)as the target contaminant,we proposed five key parameters(the observed pseudo-first-order rate constant,kobs;average mineralization rate,rm;utilization efficiency of catalyst,Ucat;utilization efficiency of oxidant,Uox;and net utilization efficiency of oxidant,Uox')to quantify the comprehensive degradation performance of *** irradiation affected target pollutants,catalysts,and oxidants,leading to an improved degradation performance of *** heterogeneous catalysts were compared in terms of the key elements ***,Co,and Mn-based materials performed better,while carbon-based catalysts performed poorly on NOR *** overall degradation performance of NOR was different for PMS and PDS,which can be ascribed to their varied reaction pathways towards NOR,but stemmed from different properties of PMS and ***,the effect of pH on the degradation efficiency of NOR was investigated.A neutral solution was optimal for PMS system,while an acidic solution worked better for PDS ***,we analyzed the molecule structure of NOR by density functional theory(DFT)calculation to study the sites easy to ***,we summarized four typical degradation pathways of NOR in SO_(4)^(-)-based AOP systems,including defluorination,piperazine ring cleavage,piperazine ring oxidation,and quinoline group transformation.

关键词： Persulfate-based AOPs Sulfate radical Norfloxacin Heterogeneous catalysts Antibiotic degradation

Applications of chemical imaging techniques in paleontology

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National Science Review 2019年第5期6卷 1040-1053页

作者： Yanhong pan Liang Hu Tao zhao CAS Key Laboratory of Economic Stratigraphy and Palaeogeography Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of Sciences

Chemical imaging techniques, based on a combination of microscopy and spectroscopy, are designed to analyse the composition and spatial distribution of heterogeneous chemical complexes within a *** the last few decades, it has become an increasingly popular tool for characterizing trace elements,isotopic information and organic biomarkers(molecular biosignatures) found in ***, we introduce the analytical principle of each technique and the interpretation of the chemical signals, followed by a review of the main applications of these techniques in *** also demonstrate that each technique is associated with pros and cons, and the current limitations and obstacles associated with the use of each specific technique should be taken into account before being applied to fossil ***, we propose that, due to the rapid advances in the available technology and overall trends towards more multi-disciplinary studies in paleontology, chemical imaging techniques can be expected to have broader applications in paleontology in the near future.

关键词： trace elements isotopic information organic biomarkers fossil materials limits and obstacles

Adaptive Fuzzy Torque Control of Passive Torque Servo Systems Based on Small Gain Theorem and Input-to-state Stability

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Chinese Journal of Aeronautics 2012年第6期25卷 906-916页

作者： WANG Xingjian WANG Shaoping zhao pan School of Automation Science and Electrical Engineering Beihang University Beij ing 100191 China Science and Technology on Aircraft Control Laboratory Beihang University Beijing 100191 China

Passive torque servo system （PTSS） simulates aerodynamic load and exerts the load on actuation system, but PTSS endures position coupling disturbance from active motion of actuation system, and this inherent disturbance is called extra torque. The most important issue for PTSS controller design is how to eliminate the influence of extra torque. Using backstepping technique, adaptive fuzzy torque control （AFTC） algorithm is proposed for PTSS in this paper, which reflects the essential characteristics of PTSS and guarantees transient tracking performance as well as final tracking accuracy. Takagi-Sugeno （T-S） fuzzy logic system is utilized to compensate parametric uncertainties and unstructured uncertainties. The output velocity of actuator identified model is introduced into AFTC aiming to eliminate extra torque. The closed-loop stability is studied using small gain theorem and the control system is proved to be semiglobally uniformly ultimately bounded. The proposed AFTC algorithm is applied to an electric load simulator （ELS）, and the comparative experimental results indicate that AFTC controller is effective for PTSS.

关键词： flight simulation adaptive control fuzzy control passive torque servo system electric load simulator extra torque small gain theorem input-to-state stability