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Optimizing mechanical properties of HIPS fabricated with low-cost desktop 3D printers:investigating the impact of process parameters

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Advances in Manufacturing 2024年第2期12卷 379-395页

作者： jin-ting Xu Guang-Wei Zhang Man-Man Chen School of Automotive Engineering Dalian University of TechnologyDalian116024People’s Republic of China

Recently,low-cost desktop three-dimensional(3D)printers,employing the fused deposition modeling(FDM)technique,have gained widespread ***,most users cannot test the strength of printed parts,and little information is available about the mechanical properties of printed high-impact polystyrene(HIPS)parts using desktop 3D *** this study,the user-adjustable parameters of desktop 3D printers,such as crisscross raster orientation,layer thickness,and infill density,were *** experimental plans were designed using the Box-Behnken method,and tensile,3-point bending,and compression tests were carried out to determine the mechanical responses of the printed *** prediction models of the process parameters were regressed to produce the optimal combination of process *** experimental results showcase that the crisscross raster orientation has significant effects on the flexural and compression strengths,but not on the tensile *** an increase in the layer thickness,the tensile,flexural,and compression strengths first decreased and then increased,reaching their minimum values at approximately 0.16 mm layer *** addition,they all increased with an increase of infill *** was demonstrated that when the raster orientation,layer thickness,and infill density were 13.08°/–76.92°,0.09 mm,and 80%,respectively,the comprehensive mechanical properties of the printed HIPS were *** results can help end-users of desktop 3D printers understand the effects of process parameters on the mechanical properties,and offer practical suggestions for setting proper printing parameters for fabricating HIPS parts.

关键词： Desktop three-dimensional(3D)printers Fused deposition modeling(FDM) High-impact polystyrene(HIPS) Process parameters

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Re-delocalization of localized d-electrons in VO_(2)(R)-VS_(4)hetero-structure enables high performance of rechargeable Mg-ion batteries

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Journal of Magnesium and Alloys 2024年第5期12卷 1830-1840页

作者： Lijiao Zhou Chao Shen Xueyang Hou Zhao Fang ting jin Keyu Xie School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an 710072China School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

Rechargeable Mg-ion batteries(MIBs)have attracted much more attentions by virtue of the high capacity from the two electrons ***,the reversible Mg^(2+)diffusion in cathode materials is restricted by the strong interactions between the high-polarized bivalent Mg^(2+)ions and anionic ***,we design and propose a hetero-structural VO_(2)(R)-VS_(4)cathode,in which the re-delocalized d-electrons can effectively shield the polarity of Mg^(2+)***,the electrons should spontaneously transfer from VS_(4)to VO_(2)(R)through the interfaces of hetero-structure due to the lower work function value of VS_(4).Furthermore,the internal electrons transfer lead to the electronic injection into VO_(2)(R)from VS_(4)and the partially broken V-V dimers,indicating the presence of lone pair electrons and charge *** from the shield effect of re-delocalized electrons,and the weakened attraction between cations and O/S anions enables more S^(2-)-S_(2)^(2-)redox groups to participate the electrochemical reactions and compensate the double charge of Mg^(2+)***,VO_(2)(R)-VS_(4)hetero-structure exhibits a high specific capacity of 554 mA h g^(-1)at 50 mA g^(-1).It is believed that the charge re-delocalization of cathode extremely boost the Mg^(2+)ions migration for the high-capacity of MIBs.

关键词： Mg-ion batteries Cathode Charge delocalization Electronic structure Heterostructure

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NaBH4-induced phase transition of CoSe_(2) with abundant Se deficiency for acidic oxygen reduction to hydrogen peroxide

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Rare Metals 2024年第2期43卷 500-510页

作者： Cai-Di Han Yong-Chao Zhang Qian Zhang jin-ting Wu Jian Gao Ji-Jun Zou Xiao-Dong Zhu State Key Laboratory Base of Eco-Chemical Engineering College of Chemical Engineering Qingdao University of Science and TechnologyQingdao266042China Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China

Electrocatalytic oxygen reduction(ORR)via the 2e−pathway to form H_(2)O_(2) in acidic medium has attracted extensive ***,the low activity,insufficient selectivity and high cost of catalysts have been the ***,CoSe_(2) with abundant Se deficiency was synthesized by a simple hydrothermal method,and the addition of NaBH4-induced CoSe_(2) phase transition from orthorhombic to cubic phase with more Se *** cubic phase CoSe_(2) with abundant Se deficiency can effectively regulate the surface electronic structure with suitable binding energies of*OOH and*O,which shows high activity,selectivity and long-term stability for acidic ORR to H_(2)O_(2).The onset potential is as low as 0.73 V *** hydrogen electrode(RHE),the H_(2)O_(2) selectivity is 84%(0 V ***),and the average electron transfer number is about ***,the H_(2)O_(2) yield measured using a flow cell is as high as 115.92 mmol·gcat.^(−1)·h^(−1) and the Faradaic efficiency is 70%at 0 V ***,which presents high potential in electrocatalytic acidic ORR to H_(2)O_(2) and organic pollutant degradation using the electron-Fenton process.

关键词： Se defected CoSe_(2) Crystal phase transition Electrocatalysis Acidic oxygen reduction Hydrogen peroxide

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The clutch size,incubation behavior of Reeves’s Pheasant(Syrmaticus reevesii) and their responses to ambient temperature and precipitation

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Avian Research 2024年第1期15卷 72-80页

作者： ting jin Shuai Lu Yunqi Wang Junqin Hua Zhengxiao Liu Qian Hu Yating Liu Yuze Zhao Jianqiang Li Jiliang Xu School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing100083China State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing100083China

Weather conditions play a pivotal role in embryo development and parental incubation costs,potentially impacting the clutch size and incubation behavior of *** these effects is crucial for bird ***’ s Pheasant(Syrmaticus reevesii) is a threatened species endemic to China,which is characterized by female-only ***,there is a lack of information regarding the impact of weather conditions on clutch size and incubation behavior in this *** satellite tracking,we tracked 27 wild female Reeves’ s Pheasants from 2020 to 2023 in Hubei Province,*** explored their clutch size and incubation behavior,as well as their responses to ambient temperature and *** size averaged 7.75 ±1.36,had an association with average ambient temperature and average daily precipitation during the egglaying period,and was potentially linked to female breeding *** the incubation period,females took an average of 0.73 ±0.46 recesses every 24 h,with an average recess duration of 100.80 ±73.37 min and an average nest attendance of 92.98 ±5.27%.They showed a unimodal recess pattern in which nest departures peaked primarily between 13:00 and 16:***,females rarely left nests when daily precipitation was *** duration and nest attendance were influenced by the interaction between daily mean ambient temperature and daily precipitation,as well as day of ***,there was a positive correlation between clutch size and recess *** results contribute valuable insights into the lifehistory features of this endangered species.

关键词： Ambient temperature Clutch size Incubation behavior Precipitation Reeves’s Pheasant

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Dispersal patterns of Reeves's pheasant based on genetic and behavioral evidence

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Current Zoology 2024年第4期70卷 480-487页

作者： Shuai Lu Xian Hou Shan Tian Zhengxiao Liu Yunqi Wang ting jin Jianqiang Li Pengcheng Wang Jiliang Xu School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China State Key Laboratory of Efficient Production of Forest Resources Bejing Forestry UniversityBeijing 100083China Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life SciencesNanjing Normal UniversityNanjing 210o23China

Dispersal is an important life history trait that plays a crucial role in avoiding *** the dispersal pattern of a threatened species facilitates conservation *** species of Galliformes are forest-dwelling terrestrial birds with a weak dispersal ability and high conservation ***,little is known about the dispersal behavior and dispersal pattern of Galliformes species such as Reeves's pheasant Syrmaticus reevesi,a globally vulnerable species endemic to ***,we integrated behavioral and genetic analyses to inves-tigate the dispersal pattern of Reeves's *** results revealed that both females and males would disperse,although the overall dispersal pattern was more likely to be ***'s pheasant population had a low level of genetic diversity and a mild level of *** low genetic diversity was resulted from fragmented habitat,and male-biased dispersal may reduce the opportunity of *** research indicated that sex-biased dispersal patterns may be a behavioral mechanism adopted by wildlife to avoid inbreeding inafragmented habitat.

关键词： animal behavior dispersal Gallformes genetic diversity satellite tracking.

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Probing the Gamma-Ray Emission Region of Five TeV Flat Spectrum Radio Quasars

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Research in Astronomy and Astrophysics 2024年第6期24卷 156-169页

作者： Hu-Bing Xiao Hai-Tao Cao Rui Xue jin-ting Cai Ge-Ge Wang Marina Manganaro Shao-Hua Zhang Zhi-Hao Ouyang Li-Ping Fu Jun-Hui Fan Shanghai Key Lab for Astrophysics Shanghai Normal UniversityShanghai 200234China School of Information Engineering Guangzhou Panyu PolytechnicGuangzhou 511483China Department of Physics Zhejiang Normal UniversityJinhua 321004China College of Mathematics and Physics Guangxi Minzu UniversityNanning 530006China Key Laboratory of Cosmology and Astrophysics(Liaoning) College of SciencesNortheastern UniversityShenyang 110819China Department of Physics University of RijekaRijeka 51000Croatia Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Key Laboratory for Astronomical Observation and Technology of Guangzhou Guangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China

The location ofγ-ray emission of blazars remains a contested topic,inspiring the development of numerous investigative techniques to address this *** this work,we analyzed Fermiγ-ray light curves in the GeV and MeV bands,employing the discrete cross-correlation function method to discern time lags between the two *** 4C+21.35,Ton 599,B21420+32,and PKS 1510-089,we identified a time lag spanning several days,while for PKS 1441+25,the time lag was not statistically *** results imply that the soft photons necessary for inverse Compton scattering predominantly originate from the dusty torus in the first four sources,whereas for PKS1441+25,they seem to be sourced mainly from the broad-line *** analysis of the opacity(τγγ)and the GeV spectra study supports the conclusion that the location of the dissipation region must be beyond the BLR to avoid significant ***,for PKS 1441+25,the emission region is also posited to lie outside yet proximate to the *** parameters of describing the emission region were obtained by fitting broadband spectral energy distribution with contemporaneous observation *** findings suggest that for the five TeV FSRQs,during Te V flaring events,the jet appears to maintain an equilibrium between the energy density of the magnetic field and that of the particles for all investigated sources,with the exceptions of 4C+21.35 and PKS1441+*** terms of the overall jet power,particle energy is the dominant contributor,and the observed blazar radiation cannot be solely attributed to the magnetic field,except in the case of 4C+***,magnetic reconnection is unlikely to be the primary mechanism behind particle acceleration in these systems.

关键词： galaxies:active gamma-rays:galaxies galaxies:jets

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土地流转、农业规模经营与农业碳排放——基于土地流转政策的准自然实验

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华中农业大学学报（社会科学版） 2024年第4期 153-163页

作者：操小娟靳婷武汉大学政治与公共管理学院/中国发展战略与规划研究院湖北武汉430072

土地流转是解决农村土地问题、实现我国农业现代化发展的重大农业变革。在“碳达峰、碳中和”的碳排放格局下,土地流转政策被视为推动农业低碳绿色发展的重要举措。现有研究指出土地流转已具备提升农业绿色效益的潜力,但并未深入探究土... 详细信息

土地流转是解决农村土地问题、实现我国农业现代化发展的重大农业变革。在“碳达峰、碳中和”的碳排放格局下,土地流转政策被视为推动农业低碳绿色发展的重要举措。现有研究指出土地流转已具备提升农业绿色效益的潜力,但并未深入探究土地流转政策实施对农业碳排放产生的影响。基于2007−2020年中国省级面板数据,通过构建准自然实验,实证分析土地流转政策实施对农业碳排放的影响机制及中介路径。研究表明:(1)基于连续型DID模型的估计结果表明,土地流转政策对农业碳排放具有一定抑制性作用;(2)影响机制分析表明,农业规模经营在政策实施过程中承担部分中介作用,能够有效实现农业减排目标;(3)地区异质性分析表明,不同地区间土地流转政策的实施结果存在差异,其中,东北、中部以及西部地区的碳减排效果均较为明显,而东部地区缺乏显著减排效应。为此,应持续支持并推广土地流转,进一步推进农业规模化经营,采取不同地方性流转政策满足各地差异化需求。

关键词：土地流转农业规模经营农业碳排放政策效应

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基于用户行为特征的深度混合推荐算法

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广西师范大学学报（自然科学版） 2024年第5期42卷 91-100页

作者：杜帅文靳婷海南大学计算机科学与技术学院海南海口570100

现有大多数推荐方法学习的是每个特征的固定表示,然而用户行为偏好随上下文特征发生变化,特征在上下文中具有不同的重要性,因此,特征的固定表示造成模型给出的推荐结果不准确。为解决此问题,本文提出基于深度因式分解机并融合信息提取... 详细信息

现有大多数推荐方法学习的是每个特征的固定表示,然而用户行为偏好随上下文特征发生变化,特征在上下文中具有不同的重要性,因此,特征的固定表示造成模型给出的推荐结果不准确。为解决此问题,本文提出基于深度因式分解机并融合信息提取单元和交叉网络结构的混合推荐模型(deep and cross factorization machine information extraction unit,IEU-DeepCFM)。首先,自注意力机制和上下文信息提取器组成的信息提取单元模块对不同上下文中的每个特征学习上下文感知特征表示;然后,利用深度交叉因式分解机在提取用户低、高阶特征的同时来挖掘用户更多的显式交叉信息;最终实现对用户行为特征的点击率预测。在MovieLens电影数据集和Avazu广告点击率数据集上进行消融和对比实验,结果表明,本文所提出的模型在AUC和LogLoss指标上均得到提高和改善,证明了该模型的合理性。

关键词：深度学习上下文特征信息提取单元推荐算法自注意力机制

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Human-like adrenal features in Chinese tree shrews revealed by multi-omics analysis of adrenal cell populations and steroid synthesis

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Zoological Research 2024年第3期45卷 617-632页

作者： jing-Hang Jiang Yi-Fu Wang Jie Zheng Yi-Ming Lei Zhong-Yuan Chen Yi Guo Ya-Jie Guo Bing-Qian Guo Yu-Fang Lv Hong-Hong Wang Juan-Juan Xie Yi-Xuan Liu ting-Wei jin Bi-Qi Li Xiao-Shu Zhu Yong-Hua Jiang Zeng-Nan Mo Center for Genomic and Personalized Medicine Guangxi Collaborative Innovation Center for Genomic and Personalized MedicineGuangxi Key Laboratory for Genomic and Personalized MedicineGuangxi Medical UniversityNanningGuangxi 530021China Department of Urology First Affiliated Hospital of Guangxi Medical UniversityNanningGuangxi 530021China Reproductive Medicine Center Jingmen People’s HospitalJingChu University of Technology Affiliated Central HospitalJingmenHubei 448000China School of Computer Science and Engineering Yulin Normal UniversityYulinGuangxi 537000China Collaborative Innovation Centre of Regenerative Medicine and Medical BioResource Development and Application Co-constructed by the Province and Ministry Guangxi Medical UniversityNanningGuangxi 530021China Department of Pathology Second Affiliated Hospital of Guangxi Medical UniversityNanningGuangxi 530007China Department of Obstetrics and Gynecology Second Affiliated Hospital of Guangxi Medical UniversityNanningGuangxi 530007China

The Chinese tree shrew(Tupaia belangeri chinensis)has emerged as a promising model for investigating adrenal steroid synthesis,but it is unclear whether the same cells produce steroid hormones and whether their production is regulated in the same way as in ***,we comprehensively mapped the cell types and pathways of steroid metabolism in the adrenal gland of Chinese tree shrews using single-cell RNA sequencing,spatial transcriptome analysis,mass spectrometry,and *** compared the transcriptomes of various adrenal cell types across tree shrews,humans,macaques,and *** showed that tree shrew adrenal glands expressed many of the same key enzymes for steroid synthesis as humans,including CYP11B2,CYP11B1,CYB5A,and *** analysis confirmed the production of aldosterone,cortisol,and dehydroepiandrosterone but not dehydroepiandrosterone sulfate in the tree shrew adrenal ***,genes in adrenal cell types in tree shrews were correlated with genetic risk factors for polycystic ovary syndrome,primary aldosteronism,hypertension,and related disorders in humans based on genome-wide association ***,this study suggests that the adrenal glands of Chinese tree shrews may consist of closely related cell populations with functional similarity to those of the human adrenal *** comprehensive results(publicly available at http://***:16245/scAGMap/)should facilitate the advancement of this animal model for the investigation of adrenal gland disorders.

关键词： Tree shrew Adrenal gland Dehydroepiandrosterone Genome-wide association studies Disease model

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开颅手术患者颅内感染的相关因素分析

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医院管理论坛 2024年第5期41卷 85-88,96页

作者：金婷温州医科大学附属第一医院

目的颅内感染是神经外科手术术后的常见并发症,本研究旨在调查开颅手术患者术后发生颅内感染的高危因素。方法回顾性选取313例开颅手术患者并收集其临床资料,通过t检验、卡方检验、logstic回归对开颅手术患者术后颅内感染的危险因素进... 详细信息

目的颅内感染是神经外科手术术后的常见并发症,本研究旨在调查开颅手术患者术后发生颅内感染的高危因素。方法回顾性选取313例开颅手术患者并收集其临床资料,通过t检验、卡方检验、logstic回归对开颅手术患者术后颅内感染的危险因素进行分析,并通过孟德尔随机化对危险因素进行验证。结果313例开颅手术患者中31例(9.90%)出现术后颅内感染。卡方检验结果显示,术后使用激素、术前ASA 3—4级、接台手术、手术时长大于3小时、病变部位位于幕下为术后颅内感染的危险因素。logstic回归模型包括激素使用情况、ASA分级、是否接台手术、手术时长,模型的曲线下面积为0.733,具有较好的预测能力。孟德尔随机化结果验证使用激素是术后感染的高危因素。结论术后使用激素、术前ASA 3—4级、接台手术、手术时长大于3小时为开颅手术后颅内感染的危险因素。

关键词：开颅手术颅内感染预测模型孟德尔随机化

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