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Quantum age of vector magnetic field measurements

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 164-165页

作者： min Jiang CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences University of Science and Technology of ChinaHefei 230026China

Magnetic fields are ubiquitous,and precise measurements of them can serve as powerful tools for deep understanding and accurate detection across multiple disciplines,including physics,biology,and chemistry[1].For instance,by measuring the magnetic fields within the human heart and brain,the medical community could obtain accurate disease diagnoses.

关键词： magnetic Quantum precise

Synthesis and characterization of carboxymethyl cellulose/organic montmorillonite nanocomposites and its adsorption behavior for Congo Red dye

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Water Science and Engineering 2013年第3期6卷 272-282页

作者： min-min WANG Li WANG College of Material Science and Art Design Inner Mongolia Agricultural University

A series of carboxymethyl cellulose/organic montmorillonite （CMC/OMMT） nanocomposites with different weight ratios of carboxymethyl cellulose （CMC） to organic montmorillonite （OMMT） were synthesized under different conditions. The nanocomposites were characterized by the Fourier transform infrared （FT-IR） spectrophotometer, X-ray diffraction （XRD） method, transmission electron microscope （TEM）, scanning electron microscope （SEM）, and thermal gravimetric （TG） analysis. The results showed that the introduction of CMC may have different influences on the physico-chemical properties of OMMT and intercalated-exfoliated nanostructures were formed in the nanocomposites. The effects of different reaction conditions on the adsorption capacity of samples for Congo Red （CR） dye were investigated by controlling the amount ofhexadecyl trimethyl ammonium bromide （CTAB）, the weight ratio of CMC to OMMT, the reaction time, and the reaction temperature. Results from the adsorption experiment showed that the adsorption capacity of the nanocomposites can reach 171.37 rag/g, with the amount of CTAB being 1.0 cation exchange capacity （CEC） of MMT, the weight ratio of CMC to OMMT being l：l, the reaction time being 6 h, and the reaction temperature being 60~C. The CMC/OMMT nanocomposite can be used as a potential adsorbent to remove CR dye from an aqueous solution.

关键词： carboxymethyl cellulose organic montmorillonite nanocomposite adsorption,Congo Red dye

Novel ensemble learning based on multiple section distribution in distributed environment

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Journal of Systems Engineering and Electronics 2008年第2期19卷 377-380页

作者： Fang min Inst. of Computer Xidian Univ. Xi'an 710071 P. R. China

Because most ensemble learning algorithms use the centralized model, and the training instances must be centralized on a single station, it is difficult to centralize the training data on a station. A distributed ensemble learning algorithm is proposed which has two kinds of weight genes of instances that denote the global distribution and the local distribution. Instead of the repeated sampling method in the standard ensemble learning, non-balance sampling from each station is used to train the base classifier set of each station. The concept of the effective nearby region for local integration classifier is proposed, and is used for the dynamic integration method of multiple classifiers in distributed environment. The experiments show that the ensemble learning algorithm in distributed environment proposed could reduce the time of training the base classifiers effectively, and ensure the classify performance is as same as the centralized learning method.

关键词： distributed environment ensemble learning multiple classifiers combination.

The Nexus between Social Networks and Sexual Practices among Female University Students

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Journal of Health Science 2017年第6期5卷 350-359页

作者： Wassie Kebede akim J. Mturi School of Social Work Addis Ababa University Addis Ababa 4839 Ethiopia School of Research and Post Graduate Studies North-West University Mafikeng 2735 South Africa

The study was conducted among college students in Addis Ababa University, Ethiopia. The objective of the study was to understand whether social networks influence students to make decisions on sexual practices. A total of 130 female students between 18-24 years participated in the study. Among them, 122 participated in the survey and eight in the case studies. The study revealed female students joined various types of social networks, which influence the decision making processes and outcomes of their sexual practices. The study has implications for women empowerment activities.

关键词： Social networks sexual practices women empowerment Ethiopia

The composite X-ray spectra of radio-loud and radio-quiet SDSS quasars

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Research in Astronomy and Astrophysics 2021年第1期21卷 33-44页

作者： min-Hua Zhou min-Feng Gu Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy ofSciences80 Nandan RoadShanghai 200030China University of Chinese Academy of Sciences 19A Yuquan RoadBeijing 100049China

We present a study of the X-ray emission for a sample of radio-detected quasars constructed from the cross-matches between SDSS,FIRST catalogs and XMM-Newton archives.A sample of radio-quiet SDSS quasars without FIRST radio detection is also assembled for *** construct the optical and X-ray composite spectra normalized at rest frame 4215 A(or 2200 A)for both radio-loud quasars(RLQs)and radio-quiet quasars(RQQs)at z≤3.2,with matched X-ray completeness of 19%,redshift and optical *** the optical composite spectrum of RLQs is similar to that of RQQs,we find that RLQs have a higher X-ray composite spectrum than RQQs,consistent with previous studies in the *** dividing the radio-detected quasars into radio loudness bins,we find the X-ray composite spectra are generally higher with increasing radio ***,a significant correlation is found between the optical-to-X-ray spectral index and radio loudness,and there is a unified multi-correlation between the radio and X-ray luminosities and radio loudness in radio-detected *** results could be possibly explained with the corona-jet model,in which the corona and jet are directly related.

关键词： methods:statistical catalogs quasars:general X-rays:general

Characteristics of Pre-summer Daytime Cloud Regimes over Coastal South China from the Himawari-8 Satellite

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Advances in Atmospheric Sciences 2022年第12期39卷 2008-2023,I0001-I0015页

作者： mingxin LI Yali LUO min min State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China School of Atmospheric Sciences and Guangdong Province Key Laboratory for Climate Change and Natural Disaster StudiesSun Yat-sen UniversityGuangzhou 519082China

Using the high spatiotemporal resolution(2 km-and-10 min)data from the Advanced Himawari Imager onboard the Himawari-8 satellite,this study documents the fine-scale characteristics of daytime cloud regimes(CRs)over coastal South China during the pre-summer rainy season(April–June).Six CRs(CR1–CR6)are identified based on the joint frequency distribution of cloud top brightness temperature and cloud optical thickness,namely,the optically thin-to-moderate cloud mixture,optically thin warm clouds with cirrus,optically thick warm clouds,weak convective cloud mixture,strong convective clouds,and extreme,deep convective *** optically thick warm clouds are the major CR during April and May,with higher frequencies over land,especially along the urban agglomeration,rather than the offshore which may be an indicator of the higher aerosol concentrations being a contributing factor over the *** CRs with weak convective cloud mixtures and strong convective clouds appear more frequently over the land,while the two CRs with optically thinner clouds occur mainly *** flow patterns(SPs)are objectively identified and examined focusing on those favoring the two major rainproducing CRs(CR5 and CR6)and the highly reflective CR with optically thick warm clouds(CR3).The two SPs favoring CR5 and CR6 are characterized by abundant moisture with low-level jets after monsoon onset,and a northwest highsoutheast low pattern with strong dynamic convergence along the coastline,*** non-convective CR3 with high reflectance is related to a SP that features the western North Pacific subtropical high extending more westward,leading to a moderate moisture supply and a wide range of convective available potential energy,but also,large convective inhibition.

关键词： cloud regime monsoon onset synoptic pattern satellite data spatiotemporal distribution

Study of Surface Cell Madelung Constant and Surface Free Energy of Nanosized Crystal Grain

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1369-1374页

作者： ZHANG Wei-Jia WANG Tian-min CUI min School of Science Beijng University of Aeronutics and Astronautics Beijing 100083 China

Surface cell Madelung constant is firstly defined in calculating surface free energy of nanosized crystal grains, which explains the physical performance of small crystals and may be great benefit to make surface analysis and study dynamics of crystal nucleus growth. A new approximative expression of surface energy and relevant thermodynamic data was used in this calculation. A new formula and computing method for calculating the Madelung constant a of any complex crystals is proposed, and surface free energies and surface electrostatic energies of nanosized crystal grains as well as Madelung constant of some complex crystals are theoretically calculated in this paper. The surface free energy of nanosized crystal grain TiO2 and surface electrostatic energy（absolute value） of nanosized crystal grain α-A12O3 are found to be the biggest among other crystal grains.

关键词： Madelung constant surface free energy nanosized crystal grain

Effect of internal sloshing on added resistance of ship

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Journal of Hydrodynamics 2017年第1期29卷 13-26页

作者： min-Guk Seo Yonghwan Kim Dong-min Park Korea Research Institute of Ships and Ocean Engineering DaejeonKorea Department of Naval Architecture and Ocean Engineering Seoul National UniversitySeoulKorea

The motion responses of ships carrying liquid cargo are affected not only by external wave excitation, but also by internal sloshing-induced forces and moments. Sloshing flow is coupled with the ship motion. This means the added resistance in waves may change when sloshing occurs inside the tank of the ship. In this study, the motion responses and added resistance of a ship, coupled with the sloshing-induced internal forces and moments are considered by using the linear potential theory. The three-dimensional Rankine panel method, in which the physical quantities are represented by using B-spline basis function, is applied. The sloshing flow of inner tanks is also simulated by Using the Rankine panel method and linearized boundary value problem. To study the added resistance, a near-field method, which integrates the second-order pressure on a body surface, is applied. The model ship is a blunt modified Wigley model with two inner tanks. Numerical results obtained without inner tanks are compared with the experimental data, and then the effect of filling ratio of inner tanks on ship motion and added resistance are observed. The components that induce added resistance are examined, and the effects of surge motion on sloshing flow and added resistance are briefly considered. This study shows that the sloshing flow inside the inner tanks may significantly influence not only the motion responses, but also added resistance, especially, when the incident wave frequency approaches the resonance frequency of the sloshing flow.

关键词： Added resistance sloshing seakeeping coupled effect Rankine panel method

Twisted phonon polaritons at deep subwavelength scale

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Light(Science & Applications) 2022年第9期11卷 1960-1961页

作者： Ren-min Ma State Key Lab for Mesoscopic Physics and School of Physics Peking UniversityBeijingChina Frontiers Science Center for Nano-optoelectronics&Collaborative Innovation Center of Quantum Matter BeijingChina

Hyperbolic polariton vortices carrying reconfigurable topological charges have been realized at deep subwavelength scale.

关键词： polar phonon Hyperbolic