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Chinese Journal of Polymer Science 2024年第10期42卷 1545-1556,I0013页

作者： Miao xie Xiao-Rong Wang Zhan-Hua Wang He-Sheng Xia State Key Laboratory of Polymer Materials Engineering Polymer Research InstituteSichuan UniversityChengdu610065China School of Petrochemical Engineering Liaoning Petrochemical UniversityFushun113001China

Covalent adaptive networks(CANs)are capable of undergoing segment rearrangement after being heated,which endows the materials with excellent self-healing and reprocessing performance,providing an efficient solution to the environment pollution caused by the plastic *** main challenge remains in developing CANs with both excellent reprocessing performance and creep-resistance *** this study,a series of CANs containing dynamic covalent benzopyrazole-urea bonds were developed based on the addition reaction between benzopyrazole and isocyanate *** calculation confirmed that relatively low dissociation energy is obtained through undergoing a five-member ring transition state,confirming excellent dynamic property of the benzopyrazole-urea *** verified by the FTIR results,this nice dynamic property can be well maintained after incorporating the benzopyrazole-urea bonds into polymer *** self-healing and reprocessing performance is observed by the 3-ABP/PDMS elastomers owing to the dynamic benzopyrazole-urea *** separation induced by the aggregation of the hard segments locked the benzopyrazole-urea bonds,which also makes the elastomers display excellent creep-resistance *** hard phase locking strategy provides an efficient approach to design CANs materials with both excellent reprocessing and creep-resistance performance.

关键词： Covalent adaptive networks Self-healing polymer Dynamic covalent bond

Fully polarized Compton scattering in plane waves and its polarization transfer

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Matter and Radiation at Extremes 2024年第3期9卷 45-56页

作者： Suo Tang Yu Xin Meng Wen Mamat Ali Bake Baisong xie College of Physics and Optoelectronic Engineering Ocean University of ChinaQingdaoShandong 266100China Department of Physics Hubei UniversityWuhan 430062China Xinjiang Key Laboratory of Solid State Physics and Devices School of Physics Science and TechnologyXinjiang UniversityUrumqi 830017China Key Laboratory of Beam Technology of the Ministry of Education and College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China

Fully polarized Compton scattering from a beam of spin-polarized electrons is investigated in plane-wave backgrounds in a broad intensity region from the perturbative to the nonperturbative *** the perturbative regime,polarized linear Compton scattering is considered for investigating polarization transfer from a single laser photon to a scattered photon,and in the high-intensity region,the polarized locally monochromatic approximation and locally constant field approximation are established and are employed to study polarization transfer from an incoming electron to a scattered *** numerical results suggest an appreciable improvement of about 10%in the scattering probability in the intermediate-intensity region if the electron’s longitudinal spin is parallel to the laser *** longitudinal spin of the incoming electron can be transferred to the scattered photon with an efficiency that increases with laser intensity and collisional *** collision between an optical laser with frequency1 eV and a 10 GeV electron,this polarization transfer efficiency can increase from about 20%in the perturbative regime to about 50%in the nonperturbative regime for scattered photons with relatively high energy.

关键词： polarized scattered transfer

Control Policy Learning Design for Vehicle Urban Positioning via BeiDou Navigation

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Journal of Systems Science & Complexity 2024年第1期37卷 114-135页

作者： QIN Yahang ZHANG Chengye CHEN Ci xie Shengli LEWIS Frank L School of Automation Guangdong University of TechnologyGuangzhou 510006China Guangdong Key Laboratory of IoT Information Technology Guangzhou 510006China. Center for Intelligent Batch Manufacturing Based on IoT Technology Key Laboratory of Intelligent Detection and The Internet of Things in Manufacturing Ministry of EducationGuangzhou 510006China Guangdong-HongKong-Macao Joint Laboratory for Smart Discrete Manufacturing Guangzhou 510006China Key Laboratory of Intelligent Information Processing and System Integration of IoT Ministry of EducationGuangzhou 510006China. UTA Research Institute The University of Texas at ArlingtonFort WorthTX 76019USA

This paper presents a learning-based control policy design for point-to-point vehicle positioning in the urban environment via BeiDou *** navigating in urban canyons,the multipath effect is a kind of interference that causes the navigation signal to drift and thus imposes severe impacts on vehicle localization due to the reflection and diffraction of the BeiDou ***,the authors formulated the navigation control system with unknown vehicle dynamics into an optimal control-seeking problem through a linear discrete-time system,and the point-to-point localization control is modeled and handled by leveraging off-policy reinforcement learning for feedback *** proposed learning-based design guarantees optimality with prescribed performance and also stabilizes the closed-loop navigation system,without the full knowledge of the vehicle *** is seen that the proposed method can withstand the impact of the multipath effect while satisfying the prescribed convergence rate.A case study demonstrates that the proposed algorithms effectively drive the vehicle to a desired setpoint under the multipath effect introduced by actual experiments of BeiDou navigation in the urban environment.

关键词： BeiDou navigation multipath effect prescribed convergence rate reinforcement learning urban localization.

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良性前列腺增生相关性血尿的彩色多普勒表现

临床泌尿外科杂志 2010年第2期25卷 130-132页

作者：谢国海严泽军程跃尹凤英浙江省宁波市第一医院泌尿外科浙江315000 浙江省宁波市第一医院超声影像科

目的:探讨前列腺增生相关性血尿的经直肠彩色多普勒超声特征。方法:对53例诊断为前列腺增生患者经直肠超声观察其前列腺动脉尿道支,测量其最大血流速度(V_(max))、最小血流速度(V_(min))、阻力指数(RI)。进行统计学处理。结果:良性前列... 详细信息

目的:探讨前列腺增生相关性血尿的经直肠彩色多普勒超声特征。方法:对53例诊断为前列腺增生患者经直肠超声观察其前列腺动脉尿道支,测量其最大血流速度(V_(max))、最小血流速度(V_(min))、阻力指数(RI)。进行统计学处理。结果:良性前列腺增生相关性血尿组及非血尿组前列腺动脉V_(max)均值分别为(23.07±3.71)cm/s、(17.12±4.25)cm/s(P=0.00),V_(min)均值分别为(4.75±3.26)cm/s、(5.07±2.54)cm/s(P=0.35),RI均值分别为(0.79±0.035)、(0.67±0.041)(P=0.00)。结论:经直肠彩色多普勒超声可显示前列腺动脉尿道支,出现前列腺增生相关性血尿的患者,前列腺腺体血流信号增加,前列腺动脉最大血流速度增快,血供增加,血管阻力指数增大。V_(max)及RI可作为良性前列腺增生相关性血尿的预测指标。

关键词：经直肠彩色多普勒超声良性前列腺增生血尿

Milling degree affects the fermentation properties of rice:perspectives from the composition of nutrients and gut microbiota via in vitro fermentation

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Food Science and Human Wellness 2024年第3期13卷 1578-1588页

作者： Yu Zhang Fan Li Shutong Pan Bing Bai Kai Huang Sen Li Hongwei Cao Tian xie Jian xie Xiao Guan School of Health Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China National Grain Industry(Urban Grain and Oil Security)Technology Innovation Center Shanghai 200093China Nutrition&Health Research Institute Co.Ltd. COFCO CorporationBeijing 102209China China Grain Wuhan Scientific Research&Design Institute Co.Ltd. Wuhan 430079China

Fermentation substrates of rice with different milling degrees(MDs) were prepared and fermented with human feces to compare their fermentation properties and effects on gut *** 0s,MD 5s and MD 60s represented brown rice,moderately-milled rice and white rice,*** in vitro fermentation,the MD 5s group showed higher starch utilization,compared with the MD 0s and 60s groups evaluated by Fourier transform infrared spectrometer,and confocal laser scanning *** of fermentation substrates of rice with different MDs on gut microbiota were evaluated by 16S rDNA *** the sample groups reduced the pH and produced short-chain fatty acids(SCFAs) and branched-chain fatty *** MD 5s group exhibited higher α-diversity than the MD 0s and 60s *** of Phascolarctobacterium,Blautia and norank_f_Ruminococcaceae were higher in the MD 0s and 5s groups,compared with the MD 60s *** bacteria were also positively correlated with the SCFAs production via Spearman correlation *** vitro culture assay revealed that fermentation substrates of MD 0s and 5s promoted the growth of two probiotics(Akkermansia muciniphila and Bifidobacterium adolescentis).Our results showed that moderate milling might be an appropriate way to produce rice products with richer nutrients and better fermentation properties.

关键词： Rice processing Milling Whole grains Gut microbiota

Solvation structure design for stabilizing MXene in transition metal ion solutions

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SusMat 2024年第3期4卷 214-226页

作者： Jie Wang Guohao Li Guanshun xie Zhaohui Huang Peng Zhang Benhua Xu Xiuqiang xie Nan Zhang College of Materials Science and Engineering Hunan UniversityChangshaChina Qinghai Provincial Engineering Research Center of High-Performance Light Metal Alloys and Forming Qinghai Provincial Key Laboratory of New Light AlloysQinghai UniversityXiningChina Chemical Engineering College Qinghai UniversityXiningChina

Although MXene has attracted great interest in diverse fields,it is susceptible to oxidation in water(H_(2)O)with transition metal ions such as Co^(2+),Fe^(2+),and Cu^(2+),which is pronounced at high *** impedes the preparation of MXene-based composites and their functional ***,this study revealed that Co^(2+)increases the maximum and average atomic charge of H in H_(2)O to improve the reactivity of H_(2)O,which leads to the fact that Co^(2+)catalyzes the oxidation of Ti_(3)C_(2)T_(x)***,the addition of N,Ndimethyl formamide(DMF)reduces theH_(2)Oactivity and improves the oxidation stability of Ti_(3)C_(2)T_(x)in the presence of Co^(2+)via preferentially forming coordination bonds with Co^(2+).This strategy is also effective in enhancing the oxidation tolerance of Ti_(3)C_(2)T_(x)to Fe^(2+)in H_(2)***,it is feasible to enhance the oxidation stability of Ti2CTx MXene in H_(2)O with the existence of Co^(2+).By virtue of these,the CoO/Ti_(3)C_(2)T_(x)composite was successfully prepared without obvious Ti_(3)C_(2)T_(x)oxidation,which is desirable to harness the advantages of Ti_(3)C_(2)T_(x)as the complementary component for lithium-ion *** work provides a straightforward paradigm to enhance the oxidation resistance of MXene in H_(2)O in the presence of transition metal ions and at high temperatures,which opens a new vista to use MXene for target applications.

关键词： hydrogen bonds N N-dimethyl formamide solvation structure stability Ti_(3)C_(2)T_(x)MXene transition metal ions

The Ω(2012) as a Hadronic Molecule

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Chinese Physics Letters 2024年第8期41卷 13-16页

作者： Ju-Jun xie Li-Sheng Geng Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Sciences and Technology University of Chinese Academy of SciencesBeijing 101408China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China School of Physics Beihang UniversityBeijing 102206China Beijing Key Laboratory of Advanced Nuclear Materials and Physics Beihang UniversityBeijing 102206China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China

Recently,a new excited baryon state,Ω(2012),was observed in the invariant mass spectra of𝐾K^(-)■^(0) and K_(S)^(0)■^(-)by the Belle *** state has a narrow width(∼6 MeV)compared to other baryon states with a similar ***,we provide a mini-review on the Ω(2012)state from the molecular perspective,where it appears to be a dynamically generated state with spin-parity 3/2^(−)from the coupled-channels interactions of the K■(1530)and ηΩ in s-wave and K■ in𝑑***,alternative explanations for the Ω(2012)resonance are also discussed.

关键词： wave. invariant state

Integrated optical frequency transfer and optical physical layer key distribution with enhanced link reciprocity detection

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Science China(Information Sciences) 2024年第7期67卷 335-336页

作者： Kunfeng xie Liang HU Jianping CHEN Guiling WU State Key Laboratory of Advanced Optical Communication System and Networks Department of Electronic EngineeringShanghai Jiao Tong University

Optical fiber transmission has been widely used in communications and metrology, wherein optical frequency transfer (OFT) and optical physical layer secure key distribution (OKD) have become research hotspots [1, 2]. Moreover,OFT can perform a comparison between state-of-the-art optical atomic clocks and implement coherent optical phase transfer over long distances to support geodesy [1, 3].

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Prediction of Lubricant Physicochemical Properties Based on Gaussian Copula Data Expansion

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 161-174页

作者： Feng Xin Yang Rui xie Peiyuan Xia Yanqiu School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China

The composition of base oils affects the performance of lubricants made from *** paper proposes a hybrid model based on gradient-boosted decision tree(GBDT)to analyze the effect of different ratios of KN4010,PAO40,and PriEco3000 component in a composite base oil system on the performance of *** study was conducted under small laboratory sample conditions,and a data expansion method using the Gaussian Copula function was proposed to improve the prediction ability of the hybrid *** study also compared four optimization algorithms,sticky mushroom algorithm(SMA),genetic algorithm(GA),whale optimization algorithm(WOA),and seagull optimization algorithm(SOA),to predict the kinematic viscosity at 40℃,kinematic viscosity at 100℃,viscosity index,and oxidation induction time performance of the *** results showed that the Gaussian Copula function data expansion method improved the prediction ability of the hybrid model in the case of small *** SOA-GBDT hybrid model had the fastest convergence speed for the samples and the best prediction effect,with determination coefficients(R^(2))for the four indicators of lubricants reaching 0.98,0.99,0.96 and 0.96,***,this model can significantly reduce the model’s prediction error and has good prediction ability.

关键词： base oil data augmentation machine learning performance prediction seagull algorithm

Geochronology and Geochemistry of Ore-related Granitoids in the Giant Gariatong Rb Deposit,Tibet and Implications for Rb Metallogeny in China

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 83-103页

作者： LIN Bin TANG Juxing TANG Pan SUN Yan QI Jing MSANTOSH xie Jinling DENG Shilin LI Faqiao xie Fuwei ZHOU Aorigele MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China SinoProbe Laboratory Chinese Academy of Geological SciencesBeijing 100094China The Key Laboratory of the Ministry of Education on Solid Waste Treatment and Recycling School of Environment and ResourceSouthwest University of Science and TechnologyMianyangSichuan 621010China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Department of Earth Sciences University of AdelaideAdelaide SA-5005Australia Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 610031China Regional Geological Survey Team of the Tibetan Bureau of Geology and Mineral Exploration and Development Lhasa 851400China College of Earth Science and Key Laboratory of Tectonic Controlled Mineralization and Oil Reservoirs Chengdu University of TechnologyChengdu 610059China

Rubidium(Rb)deposits mostly occur in the South China and Central Asia orogenic belts and are often closely associated with highly differentiated *** study investigates a newly-discovered giant Rb deposit at Gariatong in the Central Lhasa terrane in *** field studies and logging data revealed that the Rb mineralization mainly occurs in monzogranite and is related to ***-ICP-MS U-Pb dating of zircon yielded ages of 19.1±0.2 Ma and 19.0±0.2 Ma for greisenized monzogranite and fresh monzogranite,*** monzogranites are characterized as strongly peraluminous,with high contents of SiO2,Al2O3,K2O and Na2O as well as a high differentiation *** are enriched in light rare earth and large ion lithophile elements with significant negative Eu anomalies and depleted high fieldstrength *** and geochemical features of these ore-related monzogranites suggest that they are highly fractionated S-type granites,derived from remelting of crustal materials in a post-collisional *** geochemistry of zircon and apatite points to a low oxygen fugacity of the ore-related monzogranite during the magma’s *** discovery of the Gariatong Rb deposit suggests that the Central Lhasa terrane may be an important region for rare metal mineralization.

关键词： LA-ICP-MS U-Pb dating geochemistry Rb metallogeny Gariatong Tibet