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Separation and purification of Yb_(2)O_(3) by ion exchange chromatography and preparation of ultra-high purity Yb_(2)O_(3)

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Rare Metals 2023年第8期42卷 2725-2735页

作者： Xi-Juan pan zhi-Qing Yang Yang Xu Meng Wang Xiao-Wei Huang Zong-Yu Feng Qiang zhong Xin-Lin Peng National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing 100088China GRIREM HI-TECH Co. Ltd.Langfang 065201China GRIREM Advanced Materials Co. Ltd.Beijing 100088China General Research Institute for Nonferrous Metals Beijing 100088China

Ultra-high purity Yb_(2)O_(3) is the critical material of many high-tech materials such as laser glass and fiber,in which impurities seriously affect the laser color quality,intensity and *** order to reduce the influence of impurities on the properties of laser materials,the purification process of Yb_(2)O_(3) was studied by comparing two kinds of resins(RT-1 and RS-1)using improved ion-exchange chromatography(IEC)*** this study,through the synergistic improvement of resin structure and eluting system,the environmental pollution caused by ammonia water in the traditional IEC method was reduced,and the requirements of high temperature and pressure were *** ion exchange behavior and impurity removal mechanism in the resin column during the loading and eluting process were compared and *** experimental results show that RS-1 resin is all superior to RT-1resin in elements selectivity,ion exchange capacity and impurities removal *** separation and purification by IEC with RS-1 resin,the total removal rate of rare earth impurities was 77.59%and that of non-rare earth impurities was 95.86%when Yb recovery was more than 70%,both higher than that of RT-1 resin(73.26%and 83.18%).This indicates that the improved IEC method is very effective in separating and removing different metal impurities from Yb_(2)O_(3).The pilot test results of IEC method separating and purifying Yb_(2)O_(3) with RS-1 resin show that the purity of Yb_(2)O_(3) can be increased from 99.9929%to 99.9997%by IEC *** has exhibited huge potential of preparing ultra-high purity Yb_(2)O_(3),especially the deep removal of non-rare earth impurities.

关键词： Ultra-high purity Yb_(2)O_(3) Ion exchange chromatography(IEC) Laser fiber Separation mechanism Impurities

Computing Degree of Maps Between Manifolds

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Acta Mathematica Sinica,English Series 2005年第6期21卷 1277-1284页

作者： Yan Hong DING Jian zhong pan Department of Mathematics Hebeg Normal University Shijiazhuang 050016 P. R. China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 P. R. China

We determine the degrees of maps between two given closed （n-1）-connected 2n-mamifolds when n ≡ 1 （mod 8）.

关键词： 2n-manifolds degree

Sulfur dioxide gas sensing at room temperature based on tin selenium/tin dioxide hybrid prepared via hydrothermal and surface oxidation treatment

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Rare Metals 2021年第6期40卷 1588-1596页

作者： Qian-Nan pan zhi-Min Yang Wei-Wei Wang Dong-zhi Zhang College of Control Science and Engineering China University of Petroleum(East China)Qingdao 266580China

In this paper,a novel SnSe/SnO_(2) nanoparticles(NPs) composite has been successfully fabricated through hydrothermal method and surface oxidation *** as-prepared sample was characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS) and transmission electron microscopy(TEM).A series of morphological and structural characteristics confirm that the SnSe/SnO_(2) NPs composite shows a core-shell structure with a SnO_(2) shell with thickness of 6 *** prepared SnO_(2) NPs and SnSe/SnO_(2) NPs composite were applied as gas-sensing materials,and their gas-sensing properties were investigated at room temperature *** results show that the response value of the SnSe/SnO_(2) composite sensor toward 100×10^(-6) SO_(2) is 15.15%,which is 1.32 times higher than that of pristine SnSe(11.43%).And the SnSe/SnO_(2) composite sensor also has a detection limit as low as 74×10^(-9) and an ultra-fast response *** enhanced gas-sensing performance is attributed to the formation of p-n heterojunction between SnSe and SnO_(2) and the appropriate SnO_(2) shell thickness.

关键词： SO_(2)gas sensor Room temperature detection Core-shell structure SnSe/SnO_(2)composite Debye length

Studies on the Structure of Kansuinine A from Euphorbia kansui

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Chinese Chemical Letters 2002年第12期13卷 1178-1180页

作者： Qin pan zhi Da MIN Department of Natural Medicine Chemistry China Pharmaceutical UniversityNanjing 210009

Kansuinine A is a macrocyclic jatrophane diterpene that was isolated from Euphorbia kansui. Further investigation of the structure was revealed that the benzoyl group located at C-8 and the position of C-3 was the pr... 详细信息

关键词： Euphorbia kansui kansuinine A.

Brain Energy Improvement as an Emerging Approach for Alzheimer’s Disease Treatment

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Neuroscience Bulletin 2021年第6期37卷 892-893页

作者： Xiaoli pan Shaoming Sang Chunjiu zhong Department of Neurology Zhongshan HospitalState Key Laboratory of Medical NeurobiologyInstitutes of Brain ScienceFudan UniversityShanghai 200032China

Alzheimer’s disease(AD),the most common type of dementia,is a devastating neurodegenerative disorder that seriously afflicts millions of patients and their families due to the lack of effective therapeutic drugs and *** the pathogenesis of this disease has always been a great challenge because AD is complicated with multiple pathophysiological features,including neurodegeneration characterized by progressive synaptic/neuronal loss leading to brain atrophy,brain Aβ deposition forming plaques,Tau hyperphosphorylation constituting neurofibrillary tangles,glial activation and neuroinflammation,and glucose hypometabolism.

关键词： Alzheimer drugs Aβ

Human Action Recognition Based on Dense Trajectories Analysis and Random Forest

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Journal of Electronic Science and Technology 2016年第4期14卷 370-376页

作者： Pin-zhong pan Chung-Lin Huang Sonix Technology HsinChu 30265HsinChu Department of M-Commerce and Multimedia Applications Asia UniversityTaichung 41354Taichung

This paper presents a human action recognition method. It analyzes the spatio-temporal grids along the dense trajectories and generates the histogram of oriented gradients （HOG） and histogram of optical flow （HOF） to describe the appearance and motion of the human object. Then, HOG combined with HOF is converted to bag-of-words （BoWs） by the vocabulary tree. Finally, it applies random forest to recognize the type of human action. In the experiments, KTH database and URADL database are tested for the performance evaluation. Comparing with the other approaches, we show that our approach has a better performance for the action videos with high inter-class and low inter-class variabilities.

关键词： Bag-of-words (BoWs) dense trajectories histogram of optical flow (HOF) histogram of oriented gradient (HOG) random forest vocabulary tree.

RT-YOLO:A Residual Feature Fusion Triple Attention Network for Aerial Image Target Detection

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Computers, Materials & Continua 2023年第4期75卷 1411-1430页

作者： pan Zhang Hongwei Deng zhong Chen College of Computer Science and Technology Hengyang Normal UniversityHengyang421002China

In recent years,target detection of aerial images of unmannedaerial vehicle(UAV)has become one of the hottest ***,targetdetection of UAV aerial images often presents false detection and *** proposed a modified you only look once(YOLO)model toimprove the problems arising in object detection in UAV aerial images:(1)A new residual structure is designed to improve the ability to extract featuresby enhancing the fusion of the inner features of the single *** the sametime,triplet attention module is added to strengthen the connection betweenspace and channel and better retain important feature information.(2)Thefeature information is enriched by improving the multi-scale feature pyramidstructure and strengthening the feature fusion at different scales.(3)A newloss function is created and the diagonal penalty term of the anchor frame isintroduced to improve the speed of training and the accuracy of *** proposed model is called residual feature fusion triple attention YOLO(RT-YOLO).Experiments showed that the mean average precision(mAP)ofRT-YOLO is increased from 57.2%to 60.8%on the vehicle detection in aerialimage(VEDAI)dataset,and the mAP is also increased by 1.7%on the remotesensing object detection(RSOD)*** results show that theRT-YOLOoutperforms other mainstream models in UAV aerial image object detection.

关键词： Attention mechanism small target detection YOLOv5s RT-YOLO

Proteomic Comparison Between Leaves from a Red-Flesh Mutant and Its Wild-Type in Sweet Orange

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Agricultural Sciences in China 2011年第8期10卷 1206-1212页

作者： pan zhi-yong DENG Xiu-xin National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070P.R.China

The red-flesh mutant Hong Anliu sweet orange is of high nutritional value due to its lycopene *** previous studies on this mutant fruits suggested that photosynthesis and oxidative stress could promote the formation of mutation ***,leaf rather than fruit is the major part for some important biological processes such as *** this study,we analyzed the proteomic alteration in leaves of the red-flesh mutant Hong Anliu *** wild type （WT）.Ten differentially expressed proteins were identified,of which two were involved in photosynthesis,three in oxidative stress,two in defense,and three in *** high up-regulation of photosynthetic proteins proved the hypothesis that enhanced photosynthesis could provide and transport more substrates into mutant fruits for carotenoid *** to the previous results in fruits,anti-oxidative proteins were highly up-regulated in leaves,suggesting the whole plant of Hong Anliu suffered from enhanced oxidative *** involved in defense and metabolism were also identified,and their possible roles in the mutation were discussed.

关键词： sweet orange lycopene accumulation proteomic photosynthesis oxidative stress

Experimental study on seismic characteristics of typical mortisetenon joints of Chinese southern traditional timber frame buildings

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Science China(Technological Sciences) 2011年第9期54卷 2404-2411页

作者： CHUN Qing YUE zhi pan JianWu Key Lab of Urban & Architectural Heritage Conservation Ministry of Education Southeast University Nanjing 210096 China Civil Engineering Department Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The seismic characteristics of four typical mortise-tenon joints of Chinese southern traditional timber frame buildings were researched, including Yanwei mortise-tenon joint （including dropping Yanwei mortise-tenon joint）, Shizigutou mortise-tenon joint, Ban mortise-tenon joint and Mantou mortise-tenon joint. Experiments on thirteen specimens were carried out. Failure modes, hysteresis curves, skeleton curves and rotational stiffness were studied. The results provided a theoretical basis for seismic research, protection and maintenance of Chinese southern traditional timber flame buildings.

关键词： Chinese southern traditional timber frame building mortise-tenon joint seismic characteristics rotational stiffness