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Exploring the mechanical behavior and microstructure of compacted loess subjected to dry-wet cycles and chemical contamination

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3673-3695页

作者： yongpeng Nie Wankui Ni Xiangfei Lü Wenxin Tuo College of Geological Engineering and Geomatics Chang'an UniversityXi'an710054China Department of Civil Engineering Nagoya Institute of TechnologyNagoya466-8555Japan School of Water and Environment Chang'an UniversityXi'an710054China

Due to climatic factors and rapid urbanization,the soil in the Loess Plateau,China,experiences the coupled effects of dry-wet cycles and chemical *** the mechanical behavior and corresponding microstructural evolution of contaminated loess subjected to dry-wet cycles is essential to elucidate the soil degradation ***,direct shear and consolidation tests were performed to investigate the variations in mechanical properties of compacted loess contaminated with acetic acid,sodium hydroxide,and sodium sulfate during dry-wet *** mechanical response mechanisms were investigated using zeta potential,mineral chemical composition,and scanning electron microscopy(SEM)*** results indicate that the mechanical deterioration of sodium hydroxidecontaminated loess during dry-wet cycles decreases with increasing contaminant concentration,which is mainly attributed to the thickening of the electrical double layer(EDL)by Nat and the precipitation of calcite,as well as the formation of colloidal flocs induced by OH,thus inhibiting the development of large pores during the dry-wet *** contrast,the attenuation of mechanical properties of both acetic acid-and sodium sulfate-contaminated loess becomes more severe with increasing contaminant concentration,with the latter being more particularly *** is primarily due to the reduction of the EDL thickness and the erosion of cement in the acidic environment,which facilitates the connectivity of pores during dry-wet ***,the salt expansion generated by the drying process of saline loess further intensifies the structural ***,the mechanical performance of compacted loess is sensitive to both pollutant type and concentration,exhibiting different response patterns in the dry-wet cycling condition.

关键词： Contaminated loess Dry-wet cycles Compressibility Shear strength Microstructural evolution

Diet xylo-oligosaccharide supplementation improves growth performance, immune function, and intestinal health of broilers

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Animal Nutrition 2024年第2期17卷 165-176页

作者： Zhiyong Rao Yue Li Xiaopeng Yang yongpeng Guo Wei Zhang Zhixiang Wang School of Animal Science and Technology Henan Agricultural University

The effects of xylo-oligosaccharides(XOS) on broiler growth performance, immune function, and intestinal health were investigated. A total of 540 one-d-old Arbor Acres Plus broilers were randomly divided into 5 groups with 6 replicates per group and 18 chickens per replicate. Broilers in the control(CON) group received a corn-soybean meal based basal diet, those in the antibiotics(ANT) group received the basal diet plus 500 mg/kg oxytetracycline, and those in XOS groups received the basal diet plus 150, 300, or 450 mg/kg XOS. Compared with CON, the body weight at 42 d and average daily gain from 1 to 42 d were significantly increased in the 150, 450 mg/kg XOS-added and ANT groups(P = 0.018),and the relative expression of claudin-1 and ZO-1 m RNA in the ileum was significantly higher in the 300and 450 mg/kg XOS-added groups(P < 0.001). The feed conversion ratios(P < 0.001) and abdominal fat rates(P = 0.012) of broilers from 1 to 42 d of age were significantly lower in all XOS-added groups than in the control group. Splenic index(P = 0.036) and bursa of Fabricius index(P = 0.009) were significantly better in the ANT group and each XOS-added group than in the control group. Compared to CON and ANT,serum Ig A(P = 0.007) and Ig G(P = 0.002) levels were significantly higher in the 300 mg/kg XOS-added group, and the relative abundance of short-chain fatty acid-producing genera(Alistipes) was also significantly higher(P < 0.001). Meanwhile, ileal villus height(P < 0.001) and ratio of villus height to crypt depth(V:C)(P = 0.001) were significantly increased in XOS-added broilers. In analysis of relationships between cecal microbes and the physical barrier of the gut, [Ruminococcus]＿torques＿group was positively correlated with m RNA expression of ileal ZO-1 and claudin-1(P < 0.05), and Bacteroides was positively correlated with increased ileal villus height and V:C(P < 0.05). Overall, XOS addition to broiler diets improved growth performance, promoted intestinal health by enh

关键词： Xylo-oligosaccharide Growth performance Intestinal health Immunity Broiler

Influence of Surface Ice Roughness on the Aerodynamic Performance of Wind Turbines

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Fluid Dynamics & Materials Processing 2024年第9期20卷 2029-2043页

作者： Xin Guan Mingyang Li Shiwei Wu Yuqi Xie yongpeng Sun School of New Energy Shenyang Engineering CollegeShenyang110136China Shenyang Key Laboratory Clean Energy Fine Comprehensive Utilization and Scheduling Energy Storage Shenyang110136China

The focus of this research was on the equivalent particle roughness height correction required to account for the presence of ice when determining the performances of wind *** particular,two icing processes(frost ice and clear ice)were examined by combining the FENSAP-ICE and FLUENT analysis *** ice type on the blade surfaces was predicted by using a multi-time step ***,the influence of variations in icing shape and ice surface roughness on the aerodynamic performance of blades during frost ice formation or clear ice formation was *** results indicate that differences in blade surface roughness and heat flux lead to disparities in both ice formation rate and shape between frost ice and clear *** ice has a greater impact on aerodynamics compared to frost ice,while frost ice is significantly influenced by the roughness of its icy surface.

关键词： Wind turbine icing blade surface roughness aerodynamic characteristics airfoil

6G New Multiple Access Technology

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China Communications 2024年第1期21卷 I0002-I0005页

作者： Yifei Yuan yongpeng Wu Lei Wang Zhifeng Yuan Wei Bai Yuanwei Liu Tsinghua University in China Carnegie Mellon University USA Wuhan University WuhanChina Southeast University NanjingChina Carleton University OttawaONCanada Nanjing University of Post and Telecommunications Shanghai Jiaotong University ShanghaiChina the School of Electronic Engineering and Computer Science Queen Mary University of London

As a basic technology at physical layer of mobile communications,non-orthogonal multiple access has been attracting wide attention across the academia and the *** the standardization of the fifth-generation(5G)of mobile communications,3GPP conducted preliminary study on non-orthogonal multiple access without reaching the consensus to standardize the technology.

关键词： technology Access attracting

Weighted sum power maximization for STAR-RIS-aided SWIPT systems with nonlinear energy harvesting

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Science China(Information Sciences) 2024年第10期67卷 343-358页

作者： Weiping SHI Cunhua PAN Feng SHU yongpeng WU Jiangzhou WANG Yongqiang BAO Jin TIAN School of Network and Communication Nanjing Vocational College of Information Technology National Mobile Communications Research Laboratory Southeast University School of Information and Communication Engineering Hainan University School of Electronic and Optical Engineering Nanjing University of Science and Technology Shanghai Key Laboratory of Navigation and Location Based Services Shanghai Jiao Tong University School of Engineering University of Kent School of Information and Communication Engineering Nanjing Institute of Technology Engineering School of Networks and Telecommunications Jinling Institute of Technology

The conventional reconfigurable intelligent surface(RIS) is limited to reflecting incident signals,thereby imposing constraints on the placement of the transmitter and receiver, which hinders achieving comprehensive signal coverage across an entire area. This paper investigates a simultaneously transmitting and reflecting(STAR)-RIS-aided simultaneous wireless information and power transfer(SWIPT) system with a nonlinear energy harvesting model under three different RIS transmission protocols: energy splitting(ES),time switching(TS), and mode switching(MS). The objective of this paper is to maximize the weighted sum power(WSP) of all energy harvesting receivers(EHRs) while ensuring fairness in the collected power among them. This is achieved by jointly optimizing the transmit beamforming at the base station(BS)and the transmission and reflection coefficients at the STAR-RIS, subject to rate constraints for information decoding receivers(IDRs), transmit power constraint at the BS, and coefficient constraints of each element at the STAR-RIS corresponding to the three protocols. Solving this optimization problem poses challenges because of the complicated objective function and numerous coupled optimization variables of the ES STAR-RIS. To address this complexity, an efficient alternating optimization(AO) approach is proposed as an iterative solution method that achieves suboptimal results. The AO algorithm is then extended to MS STAR-RIS and TS STAR-RIS. Specifically, for MS STRA-RIS, binary constraints in the STAR-RIS coefficient optimization subproblem are handled using the first-order approximation technique along with the penalty function method. For TS STAR-RIS, apart from optimizing BS transmit beamforming and STAR-RIS coefficients subproblems, the transmission and reflection time allocation of STAR-RIS also needs *** findings demonstrate that compared to conventional RIS-aided systems, utilizing three different protocols in a STAR-RIS-aided sy

关键词： STAR-RIS beamforming SWIPT alternating optimization nonlinear energy harvesting

RAD-seq data reveals robust phylogeny and morphological evolutionary history of Rhododendron

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Horticultural Plant Journal 2024年第3期10卷 866-878页

作者： Yuanting Shen Gang Yao Yunfei Li Xiaoling Tian Shiming Li Nian Wang Chengjun Zhang Fei Wang yongpeng Ma Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China Beijing Genomics of Institute ShenzhenGuangdong 518120China Guiyang Institute of Humanities and Technology GuiyangGuizhou 550025China State Forestry and Grassland Administration Key Laboratory of Silviculture in Downstream Areas of the Yellow River College of ForestryShandong Agricultural UniversityTai'anShandong 271018China The Southwest China of Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China West China Subalpine Botanical Garden Institute of BotanyChinese Academy of SciencesChengduSichuan 611834China

Rhododendron is famous for its high ornamental ***,the genus is taxonomically difficult and the relationships within Rhododendron remain *** addition,the origin of key morphological characters with high horticulture value need to be *** problems largely hinder utilization of germplasm *** studies attempted to disentangle the phylogeny of Rhododendron,but only used a few genomic markers and lacked large-scale sampling,resulting in low clade support and contradictory phylogenetic ***,we used restriction-site associated DNA sequencing(RAD-seq)data and morphological traits for 144 species of Rhododendron,representing all subgenera and most sections and subsections of this species-rich genus,to decipher its intricate evolutionary history and reconstruct ancestral *** results revealed high resolutions at subgenera and section levels of Rhododendron based on RAD-seq *** optimal phylogenetic tree and split tree recovered five lineages among ***(cladeⅠ)formed the basal *** and Azaleastrum formed cladeⅡand had sister ***Ⅲincluded all scaly rhododendron ***(cladeⅣ)formed a sister group to ***(cladeⅤ).The results of ancestral state reconstruction showed that Rhododendron ancestor was a deciduous woody plant with terminal inflorescence,ten stamens,leaf blade without scales and broadly funnelform corolla with pink or purple *** study shows significant distinguishability to resolve the evolutionary history of Rhododendron based on high clade support of phylogenetic tree constructed by RAD-seq *** also provides an example to resolve discordant signals in phylogenetic trees and demonstrates the application feasibility of RAD-seq with large amounts of missing data in deciphering intricate evolutionary ***,the reconstructed ancestral state of six important characters provides insights into the inn

关键词： Rhododendron RAD-seq Missing data Quartet sampling(QS) Ancestral state reconstruction

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Structure-regulated fluorine-containing additives to improve the performance of perovskite solar cells

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Nano Research 2024年第7期17卷 6080-6086页

作者： Peiya Chen Xiaoman Bi Hao Yan Yingjie Zhao Yihao Liu Zhuo Huang Qian Xiao yongpeng Yang Shasha Zhang Yiqiang Zhang Yanlin Song Henan Institute of Advanced Technology College of ChemistrySchool of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China Key Laboratory of Green Printing CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of Sciences(ICCAS)Beijing Engineering Research Center of Nanomaterials for Green Printing TechnologyNational Laboratory for Molecular Sciences(BNLMS)Beijing 100190China

Perovskite solar cells(PSCs)have seen remarkable progress in recent years,largely attributed to various additives that enhance both efficiency and *** these,fluorine-containing additives have garnered significant interest because of their unique hydrophobic properties,effective defect passivation,and regulation capability on the crystallization ***,a targeted structural approach to design such additives is necessary to further enhance the performance of ***,fluoroalkyl ethylene with different fluoroalkyl chain lengths(CH_(2)CH(CF_(2))nCF_(3),n=3,5,and 7)as liquid additives is used to investigate influences of fluoroalkyl chain lengths on crystallization regulation and defect *** findings indicate that optimizing the quantity of F groups plays a crucial role in regulating the electron cloud distribution within the additive *** optimization fosters strong hydrogen bonds and coordination effects with FA+and uncoordinated Pb^(2+),ultimately enhancing crystal quality and device ***,1H,1H,2H-perfluoro-1-hexene(PF_(3))with the optimal number of F presents the most effective modulation effect.A PSC utilizing PF_(3)achieves an efficiency of 24.05%,and exhibits exceptional stability against humidity and thermal *** work sheds light on the importance of tailored structure designs in additives for achieving high-performance PSCs.

关键词： perovskite solar cells fluorine number additive structure crystallization regulation defect passivation

Plant cuticles repress organ initiation and development during skotomorphogenesis in Arabidopsis

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Plant Communications 2024年第6期5卷 100-116页

作者： Yuru Ma Wenwen Chang yongpeng Li Jiahui Xu Yongli Song Xinmiao Yao Lei Wang Yu Sun Lin Guo Hao Zhang Xigang Liu Ministry of Education Key Laboratory of Molecular and Cellular Biology College of Life SciencesHebei Normal UniversityShijiazhuangHebei 050024China Hebei Research Center of the Basic Discipline of Cell Biology College of Life SciencesHebei Normal UniversityShijiazhuangHebei 050024China Hebei Collaboration Innovation Center for Cell Signaling and Environmental Adaptation College of Life SciencesHebei Normal UniversityShijiazhuangHebei 050024China Hebei Key Laboratory of Molecular and Cellular Biology College of Life SciencesHebei Normal UniversityShijiazhuangHebei 050024China State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuangHebei 050021China

After germination in the dark,plants produce a shoot apical hook and closed cotyledons to protect the quiescent shoot apical meristem(SAM),which is critical for seedling survival during *** factors that coordinate these processes,particularly SAM repression,remain *** cuticles,multilayered structures of lipid components on the outermost surface of the aerial epidermis of all land plants,provide protection against desiccation and external environmental *** and how cuticles regulate plant development are still ***,we demonstrate that mutants of BODYGUARD1(BDG1)and long-chain acyl-CoA synthetase2(LACS2),key genes involved in cutin biosynthesis,produce a short hypocotyl with an opened apical hook and cotyledons in which the SAM is activated during *** signaling represses expression of BDG1 and LACS2,as well as cutin *** analysis revealed that cuticles are critical for skotomorphogenesis,particularly for the development and function of *** and molecular analyses showed that decreased HOOKLESS1 expression results in apical hook opening in the *** hypoxia-induced expression of LITTLE ZIPPER2 at the SAM promotes organ initiation in the mutants,the de-repressed expression of cell-cycle genes and the cytokinin response induce the growth of true *** results reveal previously unrecognized developmental functions of the plant cuticle during skotomorphogenesis and demonstrate a mechanism by which light initiates photomorphogenesis through dynamic regulation of cuticle synthesis to induce coordinated and systemic changes in organ development and growth during the skotomorphogenesis-to-photomorphogenesis transition.

关键词： plant cuticles SAM quiescence organ initiation skotomorphogenesis photomorphogenesis

A VNS-NPGA Approach to Multi-Objective Optimization of Hub-and-spoke Logistics Network

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Journal of Traffic and Transportation Engineering(English Edition) 2024年

作者： Changxi Ma Chuwei Shi Yun Yang yongpeng Zhao Zhuye Xu Bo Du School of Traffic and Transportation， Lanzhou Jiaotong University Key Laboratory of Railway lndustry on Plateau Railway Transportation Intelligent Management and Control， Lanzhou Jiaotong University School of Tourism and Management， Yangling Vocational and Technical College School of New Energy and Power Engineering， Lanzhou Jiaotong University National Engineering Research Center of Highway Maintenance Technology， Changsha University of Science & Technology SMART Infrastructure Facility， University of Wollongong

To realize low-cost freight transport in the logistics network and improve the network operation efficiency， a multi-objective optimization model and the corresponding algorithm for a hub-and-spoke logistics network are proposed based on the multi-level location of hub points and channels layout. By considering the structure of the multi-level hub-and-spoke logistics network and the features of the connectivity between the hub and spoke points， the multi-objective optimization model is constructed with two objectives of minimizing the total network operation costs and the total network service time. By considering the characteristics of decision variables and models， a Variable Neighborhood Search (VNS)-Niched Pareto Genetic Algorithm (NPGA) approach with a three-stage encoding structure chromosome is proposed， where the VNS algorithm nested in NPGA is used for individual variable neighborhood search to optimize individual channel level genes， and NPGA is adopted to solve the multi-objective optimization model. To evaluate the performance of the proposed VNS-NPGA approach， a real-life case study based on a small-scale Australia Post data set was conducted， and 25 nodes of the Australia Post and 14 nodes of the Gansu Province 3-level hub-and-spoke logistics networks were established， respectively. The analysis results indicated that the network structure of multi-level hub points could avoid the detour problem existing in the traditional hub-and-spoke network， and showed better applicability in the narrow geographical structure. Compared to the traditional multi-objective evolutionary algorithms， VNS-NPGA can obtain better solutions through the distributed optimization of channel levels， avoiding the problem that a single algorithm cannot effectively deal with coupling relationships in genes.

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