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Chinese Chemical Letters 2022年第12期33卷 5092-5095页

作者： Kui Tian Gongyi Liu xiu-Qin dong Engineering Research Centre of Organosilicon Compounds&Materials Ministry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China Suzhou Institute of Wuhan University Suzhou 215123China

Highly enantioselective Rh-catalyzed partial hydrogenation of unprotected simple 2-alkyl-5-aryl-disubstituted pyrroles has been successfully developed,generating a series of chiral 1-pyrroline derivatives generally with excellent results(95%-99%yields,91%-96%ee).Moreover,2,5-aryl-1H-pyrroles were hydrogenated well in high yields and good *** efficient protocol features easily accessible substrates,wide substrate scope,well functional group compatibility,commercially available rhodium precursor and chiral *** provides a versatile route to access chiral 1-pyrroline derivatives that are of great importance in organic synthesis and pharmaceutical chemistry.

关键词： Chiral 1-pyrrolines Partial hydrogenation Unprotected simple pyrroles Regioselectivity Enantioselectivity

Effects of traditional Chinese exercises on blood glucose and hemoglobin A1c levels in patients with prediabetes: A systematic review and meta-analysis

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Journal of Integrative Medicine 2020年第4期18卷 292-302页

作者： dong-dong Yu Liang-zhen you Wan-qiu Huang Hui Cao Fan-jing Wang xiu-qin Tang Zhao-hui Fang Guo-ming Shen Yu-xiang Guan Graduate School Anhui University of Chinese MedicineHefei 230038Anhui ProvinceChina Endocrinology Department the First Affiliated HospitalAnhui University of Chinese MedicineHefei 230031Anhui ProvinceChina

Background:Traditional Chinese exercises(TCEs)have a positive effect on glycemic control and hemoglobin A1 c(HbA1 c),but there is no consensus on the benefits of TCEs for patients with ***:The objective of this study was to systematically investigate the effects of TCEs on blood glucose control in patients with *** strategy:Comprehensive retrieval of randomized controlled trials(RCTs)was carried out using PubMed,Cochrane Library,Embase,China National Knowledge Infrastructure,VIP Database for Chinese Technical Periodicals,Wanfang Data Knowledge Service Platform,China Biology Medicine disc,Google Scholar and Baidu academic *** retrieval window ranged from the establishment of the database to December 2018,and references related to the included trials were searched without language *** criteria:The study included RCTs with a clinical diagnosis of prediabetes that was also treated with *** extraction and analysis:Literature screening,data extraction and literature quality assessment were performed independently by two *** the case of disagreement,a third party was invited to negotiate and make a *** mean difference(SMD)was used to estimate the therapeutic ***-analysis was performed using Review Manager 5.3.5 and Stata *** was assessed using Q test and I2,and the source of heterogeneity was determined using Galbraith diagram and sensitivity analysis.A Q test resulting in P50%indicated significant difference and random effect model analysis was ***,a fixed effect model was ***’s and Egger’s tests were used to assess publication ***:Nine RCTs involving 485 participants were included in this *** results showed that TCEs could reduce fasting blood glucose(FBG),2 h blood glucose(2 hPBG)and HbA1 c in patients with *** treatment subgroup showed that an intervention of 6 months had better results,w

关键词： Traditional Chinese exercises Prediabetes Blood sugar Glycemic control Hemoglobin A1c Systematic review Meta-analysis

Design, Synthesis and Application of Multifunctional Chiral Aminophosphine Catalyst for Asymmetric Intermolecular Cross Rauhut-Currier Reaction

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Chinese Journal of Chemistry 2022年第17期40卷 2061-2066页

作者： Wu-Wei dong Kui Tian xiu-Qin dong Chun-Jiang Wang Engineering Research Center of Organosilicon Compounds&Materials Ministry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhanHubei430072 China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai230021 China Suzhou Institute of Wuhan University SuzhouJiangsu215123 China

A series of structurally novel multifunctional chiral aminophosphine catalysts were developed through a concise synthetic strategy from easily available starting *** highly enantioselective intermolecular cross Rauhut-Currier reactions of vinyl ketones with 3-acyl acrylates and 2-ene-1,4-diones catalyzed by(S,S)-5a were well realized,generating a wide range of the structurally important chiral multicarbonyl products in good to excellent yields with high stereocontrol(up to 97%yield,99%ee).In addition,a series of 31P NMR experiments were carried out to further investigate the catalytic process.

关键词： Asymmetric catalysis Chiral aminophosphine Intermolecular cross Rauhut-Currier reaction Chiral multicarbonyl molecules Enantioselectivity

Distributed interacted multisensor joint probabilistic data association algorithm based on D-S theory

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Science in China(Series F) 2006年第2期49卷 219-227页

作者： ZHANG Jingwei xiu Jianjuan HE you XlONG Wei Research Institute of Information Fusion Naval Aeronautical Engineering Institute Yantai 264001 China

In order to resolve the multisensor multiplied maneuvering target tracking problem, this paper presents a distributed interacted multiple model multisensor joint probabilistic data association algorithm （DIMM-MSJPDA）. First of all, the interacted multiple model joint probabilistic data association algorithm is applied to each sensor, and then the state estimation, estimation covariance, model probability, combined innovation, innovation covariance are delivered to the fusion center. Then, the tracks from each sensor are correlated and the D-S evidence theory is used to gain the model probability of an identical target. Finally, the ultimate state estimation of each target is calculated according to the new model probability, and the state estimation is transmitted to each sensor. Simulations are designed to test the tracking performance of DIMM-MSJPDA algorithm. The results show that the use of DIMM-MSJPDA algorithm enables the distributed multisensor system to track multiplied maneuvering targets and its tracking performance is much better than that of IMMJPDA algorithm.

关键词： distributed interacted multisensor data association.

Free Boundary Problems with Local-nonlocal Diffusions and Different Free Boundaries Ⅰ: Global Solution

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Acta Mathematica Sinica,English Series 2022年第12期38卷 2265-2284页

作者： xiu dong Jian Ping WANG Ming Xin WANG School of Mathematics Harbin Institute of TechnologyHarbin 150001P.R.China School of Applied Mathematics Xiamen University of TechnologyXiamen 361024P.R.China School of Mathematics and Information Science Henan Polytechnic UniversityJiaozuo 454000P.R.China

We investigate a class of ecological models with local-nonlocal diffusions and different free *** is PartⅠof a two-part series,in which the existence,uniqueness,regularity and estimates of global solution is *** spreading-vanishing dichotomy,criteria governing spreading and vanishing,long-time behavior of solution and the estimation of the spreading speed when spreading happens will be studied in the separate PartⅡ.

关键词： Local-nonlocal diffusions different free boundaries existence-uniqueness global solution

A location-aware GIServices quality prediction model via collaborative filtering

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International Journal of Digital Earth 2018年第9期11卷 897-912页

作者： Qingxi Peng Lan you Na dong State Key Lab of Software Engineering Wuhan UniversityWuhanPeople’s Republic of China Faculty of Computer Science and Information Engineering Hubei UniversityWuhanPeople’s Republic of China Institute of Space and Earth Information Science The Chinese University of Hong KongHong KongPeople’s Republic of China

The quality of GIServices(QoGIS)is an important consideration for services sharing and ***,QoGIS is a complex concept and difficult to be evaluated *** of the current studies have focused on static and non-scalable evaluation methods but have ignored location sensitivity subsequently resulting in the inaccurate QoGIS *** intensive geodata and computation,GIServices are more sensitive to the location factor than general *** paper proposes a location-aware GIServices quality prediction model via collaborative filtering(LAGCF).The model uses a mixed CF method based on time zone feature from the perspectives of both user and *** zone is taken as the location factor and mapped into the prediction process.A time zone-adjusted Pearson correlation coefficient algorithm was designed to measure the similarity between the GIServices and the target,helping to identify highly similar *** adopting a coefficient of confidence in the final generation phase,the value of the QoGIS most similar to the target services will play a dominant role in the comprehensive *** series of experiments on large-scale QoGIS data were implemented to verify the effectivity of *** results showed that LAGCF can improve the accuracy of QoGIS prediction significantly.

关键词： Location-aware QoGIS quality prediction GIServices collaborative filtering

Analysis and Modeling of Propagation in Tunnel at 3.7 and 28 GHz

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Computers, Materials & Continua 2022年第5期71卷 3127-3143页

作者： Md Abdus Samad dong-you Choi Department of Information and Communication Engineering Chosun UniversityGwangju61452Korea Department of Electronics and Telecommunication Engineering International Islamic University ChittagongChittagong4318Bangladesh

In present-day society,train tunnels are extensively used as a means of ***,to ensure safety,streamlined train operations,and uninterrupted internet access inside train tunnels,reliable wave propagation modeling is *** have experimented and measured wave propagation models in a 1674 m long straight train tunnel in South *** measured path loss and the received signal strength were modeled with the Close-In(CI),Floating intercept(FI),CI model with a frequency-weighted path loss exponent(CIF),and alpha-beta-gamma(ABG)models,where the model parameters were determined using minimum mean square error(MMSE)*** measured and the CI,FI,CIF,and ABG modelderived path loss was plotted in graphs,and the model closest to the measured path loss was identified through *** on the measured results,it was observed that every model had a comparatively lower(n<2)path loss exponent(PLE)inside the *** also determined the path loss component’s possible deviation(shadow factor)through a Gaussian distribution considering zero mean and standard deviation calculations of random error *** FI model outperformed all the examined models as it yielded a path loss closer to the measured datasets,as well as a minimum standard deviation of the shadow factor.

关键词： Path loss shadow factor telecommunications train tunnel wave propagation wireless networks

Propagation of polarized photons through a cavity withan anisotropic metamaterial

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Frontiers of physics 2016年第6期11卷 167-173页

作者： Yun-Xia dong Jing-Jiang you School of Electrical and Electronic Engineering North China Electric Power University Beijing 102206 China

We present a theoretical study of the propagation properties of polarized photons passing through the cavity with an anisotropic metamaterial. We find that the resonant peaks of transmission appear for photons polarized in a certain direction corresponding to a negative element of the permittivity tensor. This indicates the potential for applying such cavity structures as filters for photons with certain polarizations. The resonant peak of transmission for photons having a given frequency can be achieved by adjusting the thicknesses of the air and metamaterial. If the frequency of the incident photons and the thickness of the metamaterial are fixed, the cavity structure can be used as a photon switch controlled by the thickness of the air. The effect of the absorption is considered, and the result shows that the transmission peak always appears, even for metamaterials with large absorption. Finally, the polarization manipulation of such structures is explored.

关键词： anisotropic metamaterial polarized photon cavity structure

Boundedness in a chemotaxis system with nonlinear signal production

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Applied Mathematics(A Journal of Chinese Universities) 2016年第4期31卷 379-388页

作者： LIU dong-mei TAO you-shan College of Information Science & Technology Dong Hua University Department of Applied Mathematics Dong Hua University

This work deals with the zero-Neumann boundary problem to a fully parabolic chemotaxis system with a nonlinear signal production function f（s） fulfilling 0 〈 f（s）〈 Ksα for all s 〉 0, where K and α are positive parameters. It is shown that whenever 0 〈 α 〈 2/n （where n denotes the spatial dimension） and under suitable assumptions on the initial data, this problem admits a unique global classical solution that is uniformly-in-time bounded in any spatial dimension. The proof is based on some a priori estimate techniques.

关键词： Keller-Segel model nonlinear signal production prevention of blow-up.

Entanglement of Generalized Two-Mode Binomial States and Teleportation

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Communications in Theoretical Physics 2009年第4期51卷 631-636页

作者： WANG dong-Mei YU you-Hong Department of Applied Physics Zhejiang University of Technology Hangzhou 310032 China

The entanglement of the generalized two-mode binomial states in the phase damping channel is studied by making use of the relative entropy of the entanglement. It is shown that the factors of q and p play the crucial roles in control the relative entropy of the entanglement. Furthermore, we propose a scheme of teleporting an unknown state via the generalized two-mode binomial states, and calculate the mean fidelity of the scheme.

关键词： entanglement generalized two-mode binomial states teleportation