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Extracting Energy Magnetically from Plunging Region of Black-Hole Accretion Disk

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Communications in Theoretical Physics 2007年第2期47卷 374-378页

作者： LIU Dong-Mei ye Yong-chun WANG Ding-Xiong Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

An analytical expression for the jet power extracted from the plunging region between a black hole （BH） horizon and the inner edge of the disk （hereafter the PL power） is derived based on an improved equivalent circuit in BH magnetosphere with a mapping relation between the radial coordinate of the plunging region and that of the remote astrophysical load. It is shown that the PL power is of great importance in explaining jet power and dominates over the BZ and DL powers for a wide value range of the BH spin. In addition, we show that the PL power derived in our model can be fitted with the strong jet powers of several 3CR FR I radio galaxies, which cannot be explained by virtue of the BZ mechanism. Furthermore, the condition for negative energy of the accreting particles in the plunging region is discussed with the validity of the second law of BH thermodynamics.

关键词： black hole accretion disk jet power radio galaxies

A gating ultramicroporous metal-organic framework showing high adsorption selectivity,capacity and rate for xylene separation

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Science China Chemistry 2022年第8期65卷 1552-1558页

作者： Zi-Ming ye Xue-Feng Zhang De-Xuan Liu Yan-Tong Xu Chao Wang Kai zheng Dong-Dong Zhou chun-Ting He Jie-Peng Zhang Key Laboratory of Bioinorganic and Synthetic Chemistry(Ministry of Education) School of ChemistrySun Yat-Sen UniversityGuangzhou 510275China Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education/National Engineering Research Center for Carbohydrate Synthesis Jiangxi Normal UniversityNanchang 330022China 3.Guangdong Provincial Key Laboratory of New and Renewable Energy Research and DevelopmentGuangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou 510640China

Adsorptive separation of p-xylene(pX)from xylene isomers is a key process in chemical industry,but known adsorbents cannot simultaneously achieve high adsorption selectivity,capacity,and ***,we demonstrate gating ultramicropore as a solution for this *** modification of the synthetic condition gives rise to isomeric metal-organic frameworksα-[Zn(pba)](MAF-88,H2pba=4-(1H-pyrazol-4-yl)benzoic acid)andβ-[Zn(pba)](MAF-89)possessing similar pillared-column structures,porosities,and high pX capacities of 2.0 mmol g^(−1),but very different framework/pore topologies,pore sizes,and pX *** binary and ternary mixtures of liquid xylene isomers,MAF-88 with narrow one-dimensional(1D)channels shows pX selectivity of 11 and 1.6,while MAF-89 with 3D-connected quasi-discrete pores shows pX selectivity up to 221 and 46,***,differential scanning calorimetry,and time-dependent separation experiments reveal that the kinetic effects of the gating pores play more important roles than the thermodynamic effects,which is further confirmed by single-crystal X-ray diffraction and computational simulations.

关键词： metal-organic frameworks gating xylene adsorption separation

An Improved Honey Badger Algorithm through Fusing Multi-Strategies

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Computers, Materials & Continua 2023年第8期76卷 1479-1495页

作者： Zhiwei ye Tao Zhao chun Liu Daode Zhang Wanfang Bai School of Computer Science Hubei University of TechnologyWuhan430068China Xining Big Data Service Administration Xining810000China

TheHoney Badger Algorithm(HBA)is a novelmeta-heuristic algorithm proposed recently inspired by the foraging behavior of honey *** dynamic search behavior of honey badgers with sniffing and wandering is divided into exploration and exploitation in HBA,which has been applied in photovoltaic systems and optimization problems ***,HBA tends to suffer from the local optimum and low *** alleviate these challenges,an improved HBA(IHBA)through fusing multi-strategies is presented in the *** introduces Tent chaotic mapping and composite mutation factors to HBA,meanwhile,the random control parameter is improved,moreover,a diversified updating strategy of position is put forward to enhance the advantage between exploration and *** is compared with 7 meta-heuristic algorithms in 10 benchmark functions and 5 engineering *** Wilcoxon Rank-sum Test,Friedman Test and Mann-WhitneyU Test are conducted after *** results indicate the competitiveness and merits of the IHBA,which has better solution quality and convergence *** source code is currently available from:https://***/zhaotao789/IHBA.

关键词： Honey Badger Algorithm multi-strategies fusion tent chaotic mapping compound random factors

Ferroelectric Controlled Spin Texture in Two-Dimensional NbOI_(2)Monolayer

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Chinese Physics Letters 2021年第8期38卷 126-130页

作者： Qian ye Yu-Hao Shen chun-Gang Duan State Key Laboratory of Precision Spectroscopy and Key Laboratory of Polar Materials and Devices(Ministry of Education) Department of ElectronicsEast China Normal UniversityShanghai 200241China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

The persistent spin helix(PSH)system is considered to have promising applications in energy-conservation spintronics because it supports an extraordinarily long spin lifetime of ***,we predict that the existence of PSH state in two-dimensional(2 D)ferroelectric NbOI_(2)*** first-principles calculation results show that there exists Dresselhaus-type spin-orbit coupling(SOC)band splitting near the conduction-band minimum(CBM)of the NbOI_(2)*** is revealed that the spin splitting near CBM merely refers to out-of-plane spin configuration in the wave vector space,which gives rise to a long-lived PSH state that can be controlled by reversible ferroelectric *** believe that the coupling characteristics of ferroelectric polarization and spin texture in NbOI_(2)provide a platform for the realization of fully electric controlled spintronic devices.

关键词： ferroelectric splitting realization

Adversarial Heterogeneous Network Embedding with Metapath Attention Mechanism

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Journal of Computer Science & Technology 2019年第6期34卷 1217-1229页

作者： chun-Yang Ruan ye Wang Jiangang Ma Yanchun Zhang Xin-Tian Chen Shanghai Key Laboratory of Data Science School of Computer ScienceFudan UniversityShanghai 200433China Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou 510006China College of Computer Science National University of Defense TechnologyChangsha 410073China School of Science Engineering and Information TechnologyFederation University AustraliaMelbourne 3000Australia College of Engineering and Science Victoria UniversityMelbourne 3000Australia

Heterogeneous information network (HIN)-structured data provide an effective model for practical purposes in real world. Network embedding is fundamental for supporting the network-based analysis and prediction tasks. Methods of network embedding that are currently popular normally fail to effectively preserve the semantics of HIN. In this study, we propose AGA2Vec, a generative adversarial model for HIN embedding that uses attention mechanisms and meta-paths. To capture the semantic information from multi-typed entities and relations in HIN, we develop a weighted meta-path strategy to preserve the proximity of HIN. We then use an autoencoder and a generative adversarial model to obtain robust representations of HIN. The results of experiments on several real-world datasets show that the proposed approach outperforms state-of-the-art approaches for HIN embedding.

关键词： heterogeneous information network network embedding attention mechanism generative adversarial network

Regulation of epithelial function, differentiation, and remodeling in the epididymis

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Asian Journal of Andrology 2016年第1期18卷 3-9页

作者： Sylvie Breton ye chun Ruan Yoo-Jin Park Bongki Kim Center for Systems Biology Program in Membrane Biology/Nephrology Division Massachusetts General Hospital Boston MA 02114 and Harvard Medical School Boston MA 02115 USA Epithelial Cell Biology Research Centre School of Biomedical Sciences Faculty of Medicine The Chinese University of Hong Kong Hong Kong China

The epididymis is a single convoluted tubule lined by a pseudostratified epithelium. Specialized epididymal epithelial cells, the so-called principal, basal, narrow, and clear cells, establish a unique luminal environment for the maturation and storage of spermatozoa. The epididymis is functionally and structurally divided into several segments and sub-segments that create regionally distinct luminal environments. This organ is immature at birth, and epithelial cells acquire their fully differentiated phenotype during an extended postnatal period, but the factors involved in this complex process remain incompletely characterized. In the adult epididymis, the establishment of an acidic luminal pH and low bicarbonate concentration in the epididymis contributes to preventing premature activation of spermatozoa during their maturation and storage. Clear cells are proton-secreting cells throughout the epididymis, but principal cells have distinct acid/base transport properties, depending on their localization within the epididymis. Basal cells are located in all epididymal segments, but they have a distinct morphology depending on the segment and species examined. How this structural plasticity of basal cells is regulated is discussed here. Also, the role of luminal factors and androgens in the regulation of epithelial cells is reviewed in relation to their respective localization in the proximal versus distal regions of the epididymis. Finally, we describe a novel role for CFTR in tubulogenesis and epithelial cell differentiation.

关键词： basal cells clear cells principal cells pseudostratified epithelia transepithelial transport

Long-term joint effect of nutrients and temperature increase on algal growth in Lake Taihu,China

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Journal of Environmental Sciences 2011年第2期23卷 222-227页

作者： chun ye Zhemin Shen Tao Zhang Maohong Fan Yangming Lei Jianda Zhang School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China Chinese Research Academy of Environmental Sciences Beijing 100012 China School of Civil and Environmental Engineering Georgia Institute of Technology Atlanta GA 30332 USA School of Energy Resources and Department of Chemical & Petroleum Engineering University of Wyoming Laramie WY 82071 USA Jiangsu Environmental Monitoring Center 241Fenghuangxijie Road Nanjiang 210036 China

To study how global warming and eutrophication affect water ecosystems, a multiplicative growth Monod model, modified by incorporating the Arrhenius equation, was applied to Lake Taihu to quantitatively study the relationships between algal biomass and both nutrients and temperature using long-term data. To qualitatively assess which factor was a limitation of the improved model, temperature variables were calculated using annual mean air temperature （AT）, water temperature （WT）, and their average temperature （ST）, while substrate variables were calculated using annual mean total nitrogen （TN）, total phosphorus （TP）, and their weighted aggregate （R）, respectively. The nine fitted curves showed that TN and AT were two important factors influencing algal growth; AT limited growth as algal photosynthesis is mainly carried out near the water surface; N leakage of phytoplankton and internal phosphorus load from sediment explains why TN was the best predictor of peak biomass using the Monod model. The fitted results suggest that annual mean algal biomass increased by 0.145 times when annual mean AT increased by 1.0℃. Results also showed that the more eutrophic the lake, the greater the effect AT had on algal growth. Subsequently, the long-term joint effect of annual temperature increase and eutrophication to water ecosystems can be quantitatively assessed and predicted.

关键词： lake eutrophication algal bloom global warming

Genetic Diversity Within a Jackfruit (Artocarpus heterophyllus Lam.) Germplasm Collection in China Using AFLP Markers

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Agricultural Sciences in China 2010年第9期9卷 1263-1270页

作者： LI Ying-zhi MAO Qi FENG Feng ye chun-hai Horticulture and Forestry Department Guangdong Ocean University Zhanjiang 524088 P.R.China

Jackfruit is cross-pollinated and mostly seed propagated, a wide range of variation exists in fruit quality. With the development of efficient vegetative propagation methods, excellent genotypes selected from these seed propagated seedlings will gradually replace other genotypes in jackfruit producing areas. In this study, genetic diversity of 50 jackfruit accessions from three provinces in China was analyzed based on amplified fragment length polymorphic （AFLP） markers. A total of 320 unambiguous bands were produced by eight primer combinations, and 65 （20.3%） of them were polymorphic. Genetic similarity coefficients ranged from 0 to 0.9841, with an average of 0.5000, indicating a moderate genetic diversity in this collection. The dendrogram derived by unweighted pair group method with arithmetic mean algorithm （UPGMA） analysis revealed five groups, and no correlation between genetic relationship and geographical origin were found. Accessions of soft and firm flesh type were not clustered into distinct groups, neither could yearly bearing once, or twice fruit accessions. This study has provided useful information for collection and preservation of jackfruit germplasm worldwide.

关键词： jackfruit genetic diversity AFLP molecular markers

Biological crust in sand and dust storm source areas of Asia and its impact on dust emission

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Advances in Climate Change Research 2021年第3期12卷 395-408页

作者： ZHANG Jian ZHOU chun-Hong GUI Hai-Lin ZHANG Xiao-ye State Key Laboratory of Severe Weather and Key Laboratory of Atmospheric Chemistry of China Meteorological Administration&Institute of Atmospheric Composition Chinese Academy of Meteorological SciencesBeijing100081China National Meteorological Center China Meteorological AdministrationBeijing100081China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen361021China

Even though the biological crusts are critical to dust emissions,no sand and dust forecast model have considered the impacts of the biological crust in dust emission *** situation mainly comes from two scientific difficulties:there is no large scale regional biological crust data available that can be used in the forecast model;there is no quantification of how biological crusts impact on sand *** this way,we studied the distribution of biological soil crust in sand and dust storm source areas of Central and East Asia using Moderate Resolution Imaging Spectroradiometer satellite surface reflectance data collected in 2000—2019 to determine its potential impact on dust emission according to two empirical *** further evaluated the relationships between soil crust coverage,roughness length,and dust emission to study SDS source *** found that biological crust is widely distributed in SDS source areas of Central and East Asia,with coverage rates of 19.8%in Central Asian deserts,23.1%in the Gobi Desert,and 17.3%—32.8%in Chinese deserts(p>0.05).Cyanobacteria and lichen coverage has increased in Chinese deserts,reflecting the recent impacts of the Project of Returning Farmland to Grassland and Farmland to ***,biological soil crust coverage has not increased in Central Asian deserts or the Gobi Desert,and that in Central Asian deserts continues to decrease,demonstrating the complexity of the combined effects of human activities and climate change on its *** soil crust increased the roughness length of Central and East Asian SDS source areas by 0.14—0.62 *** suppression of dust emission due to biological soil crust did not change among years during the study *** horizontal and vertical dust flux inhibition coefficient(DFIC)were 2.0—11.0 and 1.7—2.9(p>0.05),respectively,clearly showing a suppressive *** of the ecological environment in some deserts can lead to the ability of these crusts to inh

关键词： Biological soil crust Dust emission Satellite retrieval Sand and dust storm source Central and East Asia