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Robust polarimetric dehazing algorithm based on low-rank approximation and multiple virtual-exposure fusion

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Photonics Research 2024年第8期12卷 1640-1653页

作者： YIFU ZHOU HANYUE WEI JIAN liANG FEIYA MA RUI YANG liYONG REN XUELONG li School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China Xi’an Key Laboratory of Optical Information Manipulation and Augmentation(OMA) Xi’an 710119China Robust(Xixian New Area)Opto-Electro Technologies Co. Ltd.Xi’an 712000China Institute of Artificial Intelligence(TeleAI) China Telecom Corp Ltd.Beijing 100033China

Polarimetric dehazing is an effective way to enhance the quality of images captured in foggy ***,images of essential polarization parameters are vulnerable to noise,and the brightness of dehazed images is usually unstable due to different environmental *** two weaknesses reveal that current polarimetric dehazing algorithms are not robust enough to deal with different *** paper proposes a novel,to our knowledge,and robust polarimetric dehazing algorithm to enhance the quality of hazy images,where a low-rank approximation method is used to obtain low-noise polarization parameter ***,in order to improve the brightness stability of the dehazed image and thus keep the image have more details within the standard dynamic range,this study proposes a multiple virtual-exposure fusion(MVEF)scheme to process the dehazed image(usually having a high dynamic range)obtained through polarimetric *** experiments show that the proposed dehazing algorithm is robust and effective,which can significantly improve overall quality of hazy images captured under different environments.

关键词： algorithm approximation image

Experimental and computational investigation on flow characteristics of rotating cavities with high inlet pre-swirl axial throughflow

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Chinese Journal of Aeronautics 2024年第4期37卷 276-293页

作者： Sipeng WANG Xiang LUO linji GUO Zeyu WU Yang BAI Zongchao li lichun MA School of Energy and Power Engineering Beihang UniversityBeijing 100191China Research Institude of Aero-Enigine Beihang UniversityBeijing 100191China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100191China Shenyang Aeroengine Research Institute Aero Engine Corporation of ChinaShenyang 110015China

As an integral part of the internal air system of aero-engines,the axial throughflow of the cooling air can interact with the cavity flow between the rotating compressor disks,forming a threedimensional,unsteady,and unstable flow *** flow characteristics in an engine-like rotating multi-stage cavity with throughflow were investigated using particle image velocimetry,flow visualization technology and three-dimensional unsteady Reynolds-Averaged Navier-Stokes (RANS)*** focus of current research was to understand the distribution of the mean swirl ratio and its variation with a wide range of non-dimensional parameters in the co-rotating cavity with high inlet pre-swirl axial *** maximum axial Reynolds number and rotational Reynolds numbers could reach 4.41×10^(4)and 1.24×10^(6),*** velocity measurement results indicate that the mean swirl ratio is greater than 1 and decreases with an increase in the radial *** flow structure is dominated by the Rossby number,and two different flow patterns (flow penetration and flow stratification) are identified and confirmed by flow visualization *** the absence of buoyancy,the flow penetration caused by the precession of the throughflow makes it easier for the throughflow to reach a high radius *** consistency of results between measurements and numerical calculations is *** study provides a theoretical basis and data support for toroidal vortex breakdown,which is of practical significance for the design of high-pressure compressor cavities.

关键词： Compressor Axial throughflow Rotating cavity flow Particle image velocimetry Unsteady RANS Flow pattern

Frequent recombination in Cynoglossus abbreviatus(Pleuronectiformes:Cynoglossidae)ribosomal 18S rDNA

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Acta Oceanologica Sinica 2024年第8期43卷 98-103页

作者： li Gong Tingqi Jiang Bilin Hu Kaixin Wang Nannan Zhang Zengliang Miao National Engineering Laboratory of Marine Germplasm Resources Exploration and Utilization Zhejiang Ocean UniversityZhoushan 316022China Marine Science and Technology College Zhejiang Ocean UniversityZhoushan 316022China

The conventional theory of concerted evolution has been used to explain the lack of sequence variation in ribosomal RNA(rRNA)genes across diverse eukaryotic ***,recent investigations into rRNA genes in flatfish genome have resulted in controversial *** study focuses on 18S rRNA genes of the widely distributed tongue sole,Cynoglossus abbreviatus(Pleuronectiformes:Cynoglossidae),aiming to explore sequence *** distinct 18S rDNA sequence types(Type A,B,R1,R2,and R3)were identified,suggesting a departure from concerted evolution.A combination of general criteria and variations in highly conserved regions were employed to detect *** results pinpointed Type A sequences as potential pseudogenes due to significant sequence variations and deviations in secondary structure within highly conserved *** types(Type R1,R2,and R3)were identified as recombinants between Type A and B sequences,with simple crossing over and gene conversion as the most likely recombination *** findings not only contribute to rRNA pseudogene identification but also shed light on the evolutionary dynamics of rRNA genes in teleost genomes.

关键词： ribosomal RNA tongue sole non-concerted evolution pseudogene crossing over gene conversion

A DNA tetrahedron-based ferroptosis-suppressing nanoparticle: superior delivery of curcumin and alleviation of diabetic osteoporosis

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Bone Research 2024年第1期12卷 227-239页

作者： Yong li Zhengwen Cai Wenjuan Ma Long Bai En Luo Yunfeng lin State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases West China Hospital of StomatologySichuan UniversityChengduSichuan 610041PR China Department of Oral and Maxillofacial Surgery Affiliated Stomatological HospitalSouthwest Medical UniversityLuzhouSichuan 646000PR China Sichuan Provincial Engineering Research Center of Oral Biomaterials ChengduSichuan 610041China

Diabetic osteoporosis(DOP)is a significant complication that poses continuous threat to the bone health of patients with diabetes;however,currently,there are no effective treatment *** patients with diabetes,the increased levels of ferroptosis affect the osteogenic commitment and differentiation of bone mesenchymal stem cells(BMSCs),leading to significant skeletal *** address this issue,we aimed to target ferroptosis and propose a novel therapeutic approach for the treatment of *** synthesized ferroptosis-suppressing nanoparticles,which could deliver curcumin,a natural compound,to the bone marrow using tetrahedral framework nucleic acid(tFNA).This delivery system demonstrated excellent curcumin bioavailability and stability,as well as synergistic properties with *** in vitro and in vivo experiments revealed that nanoparticles could enhance mitochondrial function by activating the nuclear factor E2-related factor 2(NRF2)/glutathione peroxidase 4(GPX4)pathway,inhibiting ferroptosis,promoting the osteogenic differentiation of BMSCs in the diabetic microenvironment,reducing trabecular loss,and increasing bone *** findings suggest that curcumin-containing DNA tetrahedron-based ferroptosissuppressing nanoparticles have a promising potential for the treatment of DOP and other ferroptosis-related diseases.

关键词： curcumin osteoporosis diabetic

InSAR-derived surface deformation characteristics and mining subsidence parameters in mountain coal mines

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Journal of Mountain Science 2024年第9期21卷 3139-3156页

作者： JIANG Xiaowei SHI Wenbing liANG Feng GUI Jingjing li Jiawei Key Laboratory of Karst Georesources and Environment Ministry of EducationGuizhou UniversityGuiyang 550025China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China Mountain Geohazard Prevention R&D Center of Guizhou Province Guiyang 550025China

Mining-induced surface deformation disrupts ecological balance and impedes economic *** study employs SBAS-InSAR with 107-view of ascending and descending SAR data from Sentinel-1,spanning February 2017 to September 2020,to monitor surface deformation in the Fa’er Coal Mine,Guizhou *** on the surface deformation time series reveals the relationship between underground mining and surface *** geological conditions,mining activities,duration,and ranges,the study determines surface movement parameters for the coal *** asserts that mining depth significantly influences surface movement parameters in mountainous mining *** mining depth elevates the strike movement angle on the deeper side of the burial depth by 22.84°,while decreasing by 7.74°on the shallower *** movement angles decrease by 4.06°,while downhill movement angles increase by 15.71°.This emphasizes the technology's suitability for local mining design,which lays the groundwork for resource development,disaster prevention,and ecological protection in analogous contexts.

关键词： Time-series InSAR Surface deformation Subsurface mining Mining subsidence

Synergistic extraction of rare earth elements and alumina from coal fly ash by potassium pyrosulfate

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Journal of Rare Earths 2024年第4期42卷 749-758页

作者： Jingjing Zou Yiping Sun Chunbin Guo Daye Chen Yonghong Song Yongfeng Wu Zhaotianhui li Department of Environment Science and Engineering Liaoning Technical UniversityFuxin23000China Department of Materials Science and Engineering Liaoning Technical UniversityFuxin123000 China Technology Research and Development Department Chinese Institute of Coal ScienceBeijing100013China Shenhua Zhungeer Energy and Resource Comprehensive Development Co. Ltd.Erdos10300China liaoning Yingguan High-tech Ceramic Co. Ltd.Jinzhou121213China

Although coal fly ash(CFA)contains a high content of rare earth elements(REEs),the related extraction methods have limitations because of their low efficiencies,high levels of energy consumption,and other *** address these problems,in this study,we examined the coextraction of REEs and Al_(2)O_(3)from two types of Al_(2)O_(3)-rich CFA,pulverized CFA(PCFA)and circulating fluidized bed fly ash(CFBFA)using low-temperature calcination in the presence of K_(2)S_(2)O_(7).The total REEs,heavy REEs(HREEs),and light REEs(LREEs)extraction efficiencies were determined using different K_(2)S_(2)O_(7)/Al_(2)O_(3) molar ratios and calcination temperatures and correlated with the Al_(2)O_(3) extraction efficiency using Pearson correlation coefficient *** REEs are concentrated within CFA particles encapsulated in an aluminosilicate glass phase,and the REEs extraction efficiency is related to the form of Al in *** extraction efficiencies of Al_(2)O_(3) and REEs increase as the K_(2)S_(2)O_(7)/Al_(2)O_(3) molar ratio and calcination temperature increase,and the extraction selectivity of the more industrially valuable HREEs from CFBFA is *** high K_(2)S_(2)O_(7)/Al_(2)O_(3) molar ratios,the extraction of REEs from PCFA is more efficient than that from CFBFA with the regeneration of the highly active Al-O-Si bonds in *** Al_(2)O_(3) extraction efficiencies of PCFA as well as CFBFA correlate strongly with the total REEs,HREEs,and LREEs extraction *** developed extraction technology has the potential to promote CFA valorization and expand REEs resources,thus mitigating the bottlenecks of REEs procurement.

关键词： Rare earths Alumina Coal fly ash Potassium pyrosulfate Calcination Extraction

Effects of Enclosure on Grassland Ecological and Economic Benefits in Northern China

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Chinese Geographical Science 2024年第1期34卷 67-78页

作者： HU Bo WEN Qingke XI Fengjiang li Mengyao WANG libing REN Yuejuan Aerospace Information Research Institute Chinese Academy of SciencesBeijing100094China University of Chinese Academy of Sciences Beijing100049China Inner Mongolia Remote Sensing Center Co. Ltd.Huhhot010000China Xilinhot the Maodeng pasture Xilinhot026000China China University of Mining and Technology Xuzhou221116China Shanxi Provincial Key Lab of Resources Environment and Disaster MonitoringCoal Geological Geophysical Exploration Surveying&Mapping Institute of Shanxi ProvinceJinzhong030600China

Grasslands in northern China serve the country as both an ecological barrier and a livestock production ***,installing enclosures has been becoming the major grassland restoration measure adopted by many local ***,the effects of restoration on both ecological and production benefits of grassland remain unclear for implemented grassland restoration ***,a representative rangeland in northern China,the Maodeng pasture in Inner Mongolia Autonomous Region was selected as the study area,and remote sensing monitoring analyses were carried out to quantify the ecological benefits and economic benefits from 2015 to *** results showed that:1) in terms of ecological benefits,the grassland area with a grassland coverage rate of more than 60% accounts for 32.3% of the regional area,and 86.4% of its grassland grew significantly better than the same period in2015,showing a significant improvement in grassland *** the average amount of carbon per unit area as the ecological benefit evaluation index,it increased by 27.1% to 32.48Tg C/yr from 2015 to 2021.2) In terms of economic benefits,both theoretical grass production and livestock carrying capacity increased from 2015 to *** to 2015,the theoretical grass production in 2021 increased by 24.8% to 71 900 *** livestock carrying capacity reached 52 100 sheep units in 2021,nearly 11 000 sheep units more than that in *** the study period,multiple economic indicators(on a per capita basis of permanent residents) for the pastoral area of Xilinhot City to which the Maodeng pasture belongs,have grown *** capita total income rose from 29 630 yuan(RMB) in2015 to 62 859 yuan(RMB) in *** on grassland resources to develop the pastoral ecology also broadens the potential economic development ***,the establishment of the reserve and the experiment of implanting an enclosure policy have had a significant and positive impact on Maodeng pasture’s develo

关键词： enclosure grassland ecological benefit economic benefit Maodeng pasture Inner Mongolia northern China

Temperature-sensing array using the metal-to-insulator transition of Nd_(x)Sm_(1-x)NiO_(3)

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1694-1700页

作者： Fengbo Yan Ziang li Hao Zhang Yuchen Cui Kaiqi Nie Nuofu Chen Jikun Chen School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China School of Renewable Energy North China Electric Power UniversityBeijing 102206China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

Rare-earth nickelates(RENiO_(3))show widely tunable metal-to-insulator transition(MIT)properties with ignorable variations in lattice constants and small latent heat across the critical temperature(TMIT).Particularly,it is worth noting that compared with the more commonly investigated vanadium oxides,the MIT of RENiO_(3)is less abrupt but usually across a wider range of *** sheds light on their alternative applications as negative temperature coefficient resistance(NTCR)thermistors with high sensitivity compared with the current NTCR thermistors,other than their expected use as critical temperature resistance *** this work,we demonstrate the NTCR thermistor functionality for using the adjustable MIT of Nd_(x)Sm_(1-x)NiO_(3)within 200–400 K,which displays larger magnitudes of NTCR(e.g.,more than 7%/K)that is unattainable in traditional NTCR thermistor *** temperature dependence of resistance(R–T)shows sharp variation during the MIT of Nd_(x)Sm_(1-x)NiO_(3)with no hysteresis via decreasing the Nd content(e.g.,x≤0.8),and such a R–T tendency can be linearized by introducing an optimum parallel *** sensitive range of temperature can be further extended to 210–360 K by combining a series of Nd_(x)Sm_(1-x)NiO_(3)with eight rare-earth co-occupation ratios as an array,with a high magnitude of NTCR(e.g.,7%–14%/K)covering the entire range of temperatures.

关键词： rare-earth nickelates metal-to-insulator transition correlated oxides perovskites

Responses of runoff to changes in climate and human activities in the liuhe River Basin, China

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Journal of Arid Land 2024年第8期16卷 1023-1043页

作者： li Mingqian WANG He DU Wei GU Hongbiao ZHOU Fanchao CHI Baoming School of Ecology and Environment Institute of Disaster PreventionLangfang 065201China Hebei Key Laboratory of Resource and Environmental Disaster Mechanism and Risk Monitoring Sanhe 065201China Suzhou Qianxing Environmental Engineering Co. Ltd.Suzhou 215000China College of Transportation Engineering Nanjing Tech UniversityNanjing 210000China Tianjin North China Geological Exploration General Institute Tianjin 300000China

Since the 1950s,numerous soil and water conservation measures have been implemented to control severe soil erosion in the liuhe River Basin(LRB),*** these measures have protected the upstream soil and water ecological environment,they have led to a sharp reduction in the downstream flow and the deterioration of the river ecological ***,it is important to evaluate the impact of soil and water conservation measures on hydrological processes to assess long-term runoff *** the Soil and Water Assessment Tool(SWAT)models and sensitivity analyses based on the Budyko hypothesis,this study quantitatively evaluated the effects of climate change,direct water withdrawal,and soil and water conservation measures on runoff in the LRB during different periods,including different responses to runoff discharge,hydrological regime,and flood *** runoff series were divided into a baseline period(1956-1969)and two altered periods,i.e.,period 1(1970-1999)and period 2(2000-2020).Human activities were the main cause of the decrease in runoff during the altered periods,contributing 86.03%(-29.61 mm),while the contribution of climate change was only 13.70%(-4.70 mm).The impact of climate change manifests as a decrease in flood volume caused by a reduction in precipitation during the flood *** of two flood cases indicated a 66.00%-84.00%reduction in basin runoff capacity due to soil and water conservation measures in the upstream *** and water conservation measures reduced the peak flow and total flood volume in the upstream runoff area by 77.98%and 55.16%,respectively,even with nearly double the *** runoff coefficient in the reservoir area without soil and water conservation measures was 4.0 times that in the conservation *** results contribute to the re-evaluation of soil and water conservation hydrological effects and provide important guidance for water resource planning and water conservation policy formu

关键词： runoff soil and water conservation climate variability flood human activities liuhe River Basin