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Science China Chemistry 2025年第01期 297-307页

作者： Bin Fang limin Wang Haoqin li Jiaxin Zhang Yang Ding pan pan li Bo Peng Hua Bai lin li Frontiers Science Center for Flexible Electronics Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials &Engineering Northwestern Polytechnical University Institute of Flexible Electronics (IFE Future Technologies) Xiamen University

Hepatic ischemia-reperfusion injury（HIRI） is characterized by mitochondrial dysfunction and oxidative stress. Monitoring mitochondrial hydrogen peroxide（mtH2O2） levels in real-time through super-resolution imaging is crucial for elucidating its distribution in live cells and its mechanism of action during HIRI. However, low-background fluorogenic probes have been overlooked in the context of super-resolution imaging. In this study, we developed a low-background fluorogenic probe（MitoWG） with the potential for super-resolution morphology-correlated mitochondrial identification to track the fluctuates of mtH2O2in HIRI. Activation of the desirable fluorescence properties of the probe by mtH2O2was confirmed using structural illumination microscopy（SIM）, enabling high-quality mitochondrial imaging with exceptional specificity and *** in mtH2O2levels were successfully observed in both cellular and rat models of HIRI. Furthermore, we associated the decline in mitochondrial redox homeostasis with accelerated mtH2O2production during HIRI, which triggered mitophagy deficiency and led to cell death. In conclusion, Mito-WG possesses excellent photophysical and low-background properties for SIM imaging, making it a promising tool for mtH2O2tracking in HIRI research and clinical diagnosis.

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Effect of Rotor-stator Axial Gap on the Tip Seal Leakage Flow of a Steam Turbine

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Journal of Thermal Science 2021年第3期30卷 973-982页

作者： li pan CAO lihua School of Energy and Power Engineering Northeast Electric Power UniversityJilin 132012China

The tip leakage flow in different axial gaps is numerically investigated based on the Reynolds-Averaged Navier-Stokes equations and k-ω SST turbulent model using commercial CFD software ANSYS *** characteristics of vortexes in the flow field of tip seal and the distribution law of rotor tip leakage loss are analyzed under the change of axial *** results show that the flow field in the blade tip seal undergoes complex changes with the increase of axial *** are two opposite vortices in the seal cavity with small axial gap,namely,the large vortex in the cavity and the small vortex near the wall of the *** small vortex gradually disappears with the increase of the axial *** the axial gap is increased to a certain value,the reverse large vortex is formed in the cavity behind the low teeth of seal,and the leakage rate increases significantly;the steam flow angle and the mixing loss also show different *** on the traditional calculation formula of tip leakage rate,a more accurate calculation formula of tip leakage rate is constructed by introducing equivalent labyrinth seal teeth to consider the variation of axial gap.

关键词： steam turbine axial gap tip leakage labyrinth seal prediction formulation

Evaluation of zeotropic refrigerants based on nonlinear relationship between temperature and enthalpy

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Science China(Technological Sciences) 2006年第3期49卷 322-331页

作者： ZHAO li GAO pan Department of Thermal and Refrigeration Engineering School of Mechanical Engineering Tianjin University Tianjin 300072 China Department of Thermal and Refrigeration Engineering School of Mechanical Engineering Tianjin University Tianjin 300072 China

In order to evaluate cycling characters of zeotropic refrigerants in air-con- ditioning operation, and to reveal distribution rules of temperature difference between refrigerants and heat transfer fluids in condenser and evaporator, theoretical researches were carried out based on nonlinear relationship between temperature and enthalpy in period of refrigerants’ phase change. Firstly, a phase changing model of refrigerants was built, and refrigerants state parameters were decided in the air-conditioning operation. Secondly, the state equation of refrigerants was applied for computing relationship be- tween temperature and enthalpy, else based on some suppositions, temperature differ- ences between 15 sorts of refrigerants and heat-transfer fluids were gotten too. Through concluding those temperature differences changing in condenser and evaporator, some rules were found. Lastly, after calculating and comparing the additive exergy loss among 15 sorts of refrigerants, which resulted from the changing of temperature difference, their cycling characters evaluation were presented.

关键词： zeotropic refrigerants, evaluation, phase change, temperature distribution, the additive exergy loss,air conditioning operation.

ROLE OF INTERVENING OPPORTUNITY IN TOURIST DESTINATION DEVELOPMENT

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Chinese Geographical Science 2005年第4期15卷 368-376页

作者： pan li-li BAO Ji-gang Center for Tourism Planning ＆ Re search SUN Yat-Sen University Guangzhou 510275 P. R. China College of Management Zhejiang University Hangzhou 310010 P. R. China

Intervening opportunity is an important factor in spatial interaction, and has very important impacts on tourist destination development in a region. There are few literatures on this topic in tourist researches, and especially in China fewer tourist researchers pay attention to intervening opportunity theory. This article, taking lin’an as a case study, aims to introduce intervening opportunity theory in tourist destination development by the comprehensive ana-lysis of some data including literatures, Internet information, longitudinal data and some tourist surveys. Both qualitative and quantitative methods are all used in this research. Firstly, the authors expatiate upon the definition of intervening opportunity, by reviewing the literatures in detail, take lin’an of Zhejiang Province as a case study, and then analyze some necessary factors of intervening opportunity, such as regional tourist demands and supplies, tourist attractions, spatial distance and transportation, tourist images and costs, regional competition and cooperation in tourist destinations. Finally the impacts of intervening opportunity on lin’an tourist development are analyzed in detail. The results show that intervening opportunity do not occur everywhere, and there must be some critical factors, and intervening opportunity surely plays important roles in tourist destination development. The tourist development in lin’an is attributed to intervening opportunity of the spatial location between Hangzhou and Huangshan that are two famous tourist cities in China, and the occurrence of intervening opportunities in lin’an is the integration of some external and internal factors.

关键词： intervening opportunity theory spatial competition lin'an Huangshan Hangzhou

Modulating the CO methanation activity of Ni catalyst by nitrogen doped carbon

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Journal of Energy Chemistry 2018年第3期27卷 898-902页

作者： Yaping lin pan li Tingting Cui Xiulian pan Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023Liaoning.China University of Chinese Academy of Sciences Beijing 100049China

Nitrogen doping has been proved to be an effective way to modify the properties of graphene and other carbon materials. Herein, we explore a composite with nitrogen doped carbon overlayers wrapping Si C substrate as a support for Ni（Ni/CN-Si C） and evaluate its effects on the methanation activity. The results show that both the activity and stability of Ni are enhanced. Characterization with STEM, XRD, XPS, Raman and H2-TPR indicates that nitrogen doping generates more defects in the carbon overlayers, which benefit the dispersion of Ni. Furthermore, the reduction of Ni is facilitated.

关键词： CO methanation Ni catalyst Carbon Nitrogen doping SiC

A Pixel–Channel Hybrid Attention Model for Image Processing

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Tsinghua Science and Technology 2022年第5期27卷 804-816页

作者： Qiang Hua liyou Chen pan li Shipeng Zhao Yan li College of Mathematics and Information Science Hebei UniversityBaoding 071002China Research Center for Applied Mathematics and Interdisciplinary Sciences Beijing Normal UniversityZhuhai 519087China

In the field of image processing,better results can often be achieved through the deepening of neural network layers involving considerably more *** image classification,improving classification accuracy without introducing too many parameters remains a *** for image conversion,the use of the conversion model of the generative adversarial network often produces semantic artifacts,resulting in images with lower ***,to address the above problems,a new type of attention module is proposed in this paper for the first *** proposed approach uses the pixel-channel hybrid attention(PCHA) mechanism,which combines the attention information of the pixel and channel *** comparative results of using different attention modules on multiple-image data verify the superiority of the PCHA module in performing classification *** image conversion,we propose a skip structure(S-PCHA model) in the up-and down-sampling processes based on the PCHA *** proposed model can help the algorithm identify the most distinctive semantic object in a given image,as this structure effectively realizes the intercommunication of encoder and decoder ***,the results showed that the attention model could establish a more realistic mapping from the source domain to the target domain in the image conversion algorithm,thus improving the quality of the image generated by the conversion model.

关键词： deep learning attention mechanism image classification image processing convolutional neural networks

Sorption of pyrene on two paddy soils and their particle-size fractions

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Journal of Environmental Sciences 2005年第6期17卷 962-965页

作者： li Jiu-hai pan Gen-xing Institute of Resources Ecosystem and Environment of Agriculture Nanjing Agricultural University Nanjing 210095 China

In the present study, the sorption of pyrene on two kinds of bulk paddy soils, Gleyic Stagnic Anthrosols, and Ferric accumulic Stagnic Anthrosols as well as their particle-size fractions was investigated. The sorption isotherms fitted well with Freundlich equation. For both soils, the clay fraction（〈 2μm） and coarse sand fraction（2000-250μm） had higher sorption capacity than fine sand fraction（250-20 μm） and silt fraction（20-2 μm）. The IogKoc values obtained of each soil and its particle-size fractions were similar, proving that SOM content was a key factor affecting pyrene sorption. The Kd values showed a significant correlation with contents of dithionite-extractable Fe in both paddy soils and a good relationship with CEC in Gleyic Stagnic Anthrosols, indicating possible effects of surface properties of particle-size fractions on the sorption of pyrene.

关键词： paddy soil particle-size fraction PAHs sorption

Development of genomic resources for the genus Celtis (Cannabaceae) based on genome skimming data

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Plant Diversity 2021年第1期43卷 43-53页

作者： Luxian liu Yonghua Zhang pan li Key Laboratory of Plant Stress Biology School of Life SciencesHenan UniversityKaifeng475000China Laboratory of Systematic&Evolutionary Botany and Biodiversity College of Life SciencesZhejiang UniversityHangzhou310058China College of life and Environmental Sciences Wenzhou UniversityWenzhou325035China

Celtis is a Cannabaceae genus of 60e70 species of trees,or rarely shrubs,commonly known as *** woody genus consists of very valuable forest plants that provide important wildlife habitat for birds and *** previous studies have identified its phylogenetic position,interspecific relationships within Celtis remain *** this study,we generated genome skimming data from five Celtis species to analyze phylogenetic relationships within the genus and develop genome *** plastomes of Celtis ranged in length from 158,989 bp to 159,082 bp,with a typical angiosperm quadripartite structure,and encoded a total of 132 genes with 20 duplicated in the *** analyses showed that plastome content and structure were relatively *** plastomes showed no signs of gene loss,translocations,inversions,or genome *** plastid hotspot regions(trnH-psbA,psbA-trnK,trnG-trnR,psbC-trnS,cemA-petA and rps8-rpl14),4097 polymorphic nuclear SSRs,as well as 62 low or single-copy gene fragments were identified within ***,the phylogenetic relationships based on the complete plastome sequences strongly endorse the placement of *** as sister to the((((***,***),***),***),***)*** findings and the genetic resources developed here will be conducive to further studies on the genus Celtis involving phylogeny,population genetics,and conservation biology.

关键词： Cannabaceae Genome skimming Plastome Plastid hotspot Simple sequence repeat(SSR)

Effect of hydrolysis conditions on hydrous TiO_2 polymorphs precipitated from a titanyl sulfate and sulfuric acid solution

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 642-650页

作者： Hao Song Bin liang li Lu pan Wu Chun li Department of Metallurgical Engineering Sichuan University Chengdu 610065 China

The relationship between hydrolysis conditions and hydrous titania polymorphs obtained in a titanyl sulfate and sulfmic acid solu- tion was investigated by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and high-resolution transmission electron micros- copy （HRTEM）. The results revealed that the feeding rate of the titanyl sulfate stock solution, the concentration of *** acid, and the seed dosage of mtile crystal could significantly affect the hydrolysis rate, thus influencing the titania crystal phase. Hydrous TiO2 in the form of rutile, anatase, or the mixture of both could be obtained in solutions of low titanium concentrations and 2.5wt% to 15wt% sulfuric acid at 100℃. When the hydrolysis rate of titanitma expressed by TiOa was more than or equal to 0.04 g/（***）, the hydrolysate was almost phase-pure anatase, while the main phase state was rutile when the hydrolysis rate was less than or equal to 0.01 g/（***）. With the hy- drolysis rate between 0.02 and 0.03 g/（***）, the hydrolysate contained almost equal magnitude ofrutile and anatase. It seems that although rutile phase is thermodynamically stable in very acidic solutions, anatase is a kinetically stable phase.

关键词： titanium dioxide titanyl sulfate sulfuric acid hydrolysis anatase rutile

Further insight into reproductive incompatibility between putative cryptic species of the Bemisia tabaci whitefly complex

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Insect Science 2016年第2期23卷 215-224页

作者： li Qin li-Long pan Shu-Sheng liu Ministry of Agriculture Key Laboratory of Agricultural Entomology Institute of Insect Sciences Zhejiang University Hangzhou China

The whitefly Bemisia tabaci （Gennadius）（Hemiptera： Aleyrodidae）, with its global distribution and extensive genetic diversity, is now known to be a complex of over 35 cryptic species. However, a satisfactory resolution of the systematics of this species complex is yet to be achieved. Here, we designed experiments to examine reproductive compatibility among species with different levels of mitochondrial cytochrome oxidase I （mtCOI） divergence. The data show that putative species with mtCOI divergence of 〉 8% between them consistently exhibited complete reproductive isolation. However, two of the putative species, Asia II 9 and Asia II 3, with mtCOI divergence of 4.47% between them, exhibited near complete reproductive compatibility in one direction of their cross, and partial reproductive compatibility in the other direction. Together with some recent reports on this topic from the literature, our data indicates that, while divergence in the mtCOI sequences provides a valid molecular marker for species delimitation in most clades, more genetic markers and more sophisticated molecular phylogeny will be required to achieve adequate delimitation of all species in this whitefly complex. While many attempts have been made to examine the reproductive compatibility among genetic groups of the B. tabaci complex, our study represents the first effort to conduct crossing experiments with putative species that were chosen with considerations of their genetic divergence. In light of the new data, we discuss the best strategy and protocols to conduct further molecular phylogenetic analysis and crossing trials, in order to reveal the overall pattern of reproductive incompatibility among species of this whitefly complex.

关键词： crossing experiment genetic diversity mitochondrial COI reproductiveisolation systematics whitefly