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Electrical discharge and arc milling with automatic tracking of optimal flushing direction:A novel high-efficiency compound machining method

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Chinese Journal of Aeronautics 2024年第3期37卷 351-364页

作者： Xinlei WU yonghong LIU Pengxin zhang Liang QI Dege LI Chi MA Renjie JI College of Mechanical and Electronic Engineering China University of Petroleum(East China)Qingdao 266580China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816China

The arc milling method has the advantages of high machining efficiency and low cost and is independent of the strength and hardness of machined materials.However,frequent electrode back-offs and the risk of workpiece burning may occur if erosion products are not removed promptly.In this study,it was found that the flushing method of the working medium had a significant impact on the machining performance of arc milling.Based on this,a novel highefficiency compound machining method of electrical discharge and arc milling with automatic tracking of the optimal flushing direction was proposed.An automatic tracking optimizer for external working medium injection was designed to determine the optimal external flushing direction according to the feed direction.The influence of flushing methods,working mediums,and machining parameters on the machining efficiency,tool electrode wear rate,machining error,and surface integrity of titanium alloys were investigated.The results indicated that better machining performance and environmental friendliness were achieved using the compound flushing method of outer compressed air and inner deionized water.Additionally,the automatic tracking flushing method in the opposite direction of the feed direction showed superior results compared to other directions.The material removal rate with the opposite direction injection could be increased up to 1.62 times that of the same direction,and the relative electrode wear rate could be reduced by 14.76%.This novel method has broad application prospects for machining parts with difficult-to-cut materials in aerospace and military industries.

关键词： Arc milling Dielectric Difficult-to-cut materials Electric discharge machining Erosion Material removal rate

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Eco-physiological characteristics of Tetracentron sinense Oliv.saplings in response to different light intensities

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Journal of Forestry Research 2024年第3期35卷 29-44页

作者： Rong Wang Xueheng Lu Hongyan Han Xuemei zhang yonghong Ma Qinsong Liu Xiaohong Gan Key Laboratoryof Southwest Wildlife Resources Conservation Ministry of EducationChina West Normal UniversityNanchong 637009People's Republic of China Institute of Plant Adaptation and Utilization in Southwest Mountain China West Normal UniversityNanchong 637009People's Republic of China Office of the People's Government of Yuexi County Yuexi County 616650Liangshan Yi Autonomous PrefecturePeople's Republic of China

The regeneration of Tetracentron sinense Oliv.is poor in the understory and in open areas due to the charac-teristics of natural regeneration of the species on forest edges and in gaps.It is unclear whether different light intensities in various habitats affect eco-physiological characteristics of saplings and their natural regeneration.In this study,the light intensity in T.sinense habitats was simulated by artificial shading(L1:100%NS(natural sunlight)in the open;L2:50%NS in a forest gap or edge;L3:10%NS in understory)to investigate differences in morphology,leaf structure,physiology,and photosynthesis of 2-year-old sap-lings,and to analyze the mechanism of light intensity on sapling establishment.Significant differences were observed in morphology(including leaf area,and specific leaf area)under different light intensities.Compared to L1 and L3,chloroplast structure in L2 was intact.With increasing time,superoxide dismutase(SOD)and catalase(CAT)activities in L2 became gradually higher than under the other light intensities,while malondialdehyde(MDA)content was opposite.Shading decreased osmoregulation substance contents of leaves but increased chlorophyll.The results suggest that light intensities significantly affect the eco-physiological characteristics of T.sinense saplings and they would respond most favorably at intermediate levels of light by optimizing eco-physiological characteristics.Therefore,50%natural sunlight should be created to promote saplings establishment and population recovery of T.sinense during in situ conservation,including sowing mature seeds in forest edges or gaps and providing appropriate shade protection for seedlings and saplings in the open.

关键词： Chloroplast ultrastructure Eco-physiological characteristics Light intensities Sapling establishment Tetracentron sinense Oliv

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Fire-retardant, anti-dripping, biodegradable and biobased polyurethane elastomers enabled by hydrogen-bonding with cellulose nanocrystals

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Nano Research 2024年第3期17卷 2186-2194页

作者： Yijiao Xue Tianchen zhang Hong Peng Zhewen Ma Meng zhang Mark Lynch Toan Dinh Zhezhe Zhou yonghong Zhou Pingan Song Institute of Chemical Industry of Forest Products Chinese Academy of Forestry(CAF)Nanjing 210042China School of Chemical Engineering The University of QueenslandBrisbaneQld 4072Australia Department of Polymer Materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China School of Agriculture and Environmental Science University of Southern QueenslandToowoombaQld 4300Australia Centre for Future Materials University of Southern QueenslandToowoombaQld 4300Australia

Thermoplastic polyurethane(PU)elastomers have attracted significant attention because of their many important industrial applications.However,the creation of fire-retardant and anti-dripping PU elastomers has remained a grant challenge due to the lack of crosslinking and weak interchain interactions.Herein,we report a mechanically robust,biodegradable,fire-retardant,and anti-dripping biobased PU elastomer with excellent biodegradability using an abietic acid-based compound as hard segments and polycaprolactone diol(PCL)as soft segments,followed by physically crosslinking with cellulose nanocrystals(CNC)through dynamic hydrogen-bonding.The resultant elastomer shows the balanced mechanical and fire-retardant properties,e.g.,a tensile strength and break strain of 9.1 MPa and 560%,a self-extinguishing ability(V-0 rating in UL-94 testing),and an anti-dripping behavior.Moreover,the as-developed PU can be completely degraded in 1.0 wt.%lipase solution at 37℃ in 60 days,arising from the catalytic and wicking effect of CNC on PU chains.This work provides an innovative and versatile strategy for constructing robust,fire-retardant,anti-dripping,and biodegradable PU elastomers,which hold great promise for practical applications in electronic and automobile sectors.

关键词： polyurethane elastomers cellulose nanocrystals fire retardancy anti-dripping biodegradation

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Comparative Experimental Study on Heat Transfer Characteristics of Building Exterior Surface at High and Low Altitudes

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Journal of Thermal Science 2024年第3期33卷 1119-1131页

作者： JIA yonghong GUO Shurui LI Jin GUO Lei CHENG Zhu zhang Yin YANG Hanyu LONG Enshen Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu610065China MOE Key Laboratory of Deep Earth Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu610065China

The external surface heat transfer coefficient of building envelope is one of the important parameters necessary for building energy saving design,but the basic data in high-altitude area are scarce.Therefore,the authors propose a modified measurement method based on the heat balance of a model building,and use the same model building to measure its external surface heat transfer coefficient under outdoor conditions in Chengdu city,China at an altitude of 520 m and Daocheng city at an altitude of 3750 m respectively.The results show that the total heat transfer coefficient(h_(t))of building surface in high-altitude area is reduced by 34.48%.The influence of outdoor wind speed on the convective heat transfer coefficient(h_(c))in high-altitude area is not as significant as that in low-altitude area.The fitting relation between convection heat transfer coefficient and outdoor wind speed is also obtained.Under the same heating power,the average temperature rise of indoor and outdoor air at highaltitude is 41.9%higher than that at low altitude,and the average temperature rise of inner wall is 25.8%higher than that at low altitude.It shows that high-altitude area can create a more comfortable indoor thermal environment than low-altitude area under the same energy consumption condition.It is not appropriate to use the heat transfer characteristics of the exterior surface of buildings in low-altitude area for building energy saving design and related heating equipment selection and system terminal matching design in high-altitude area.

关键词： altitude heat transfer characteristics convective heat transfer coefficient(h_(c)) radiative heat transfer coefficient(h_(r)) external building envelope

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Artificial selection of the Green Revolution gene Semidwarf 1 is implicated in upland rice breeding

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Journal of Integrative Agriculture 2024年第3期23卷 769-780页

作者： Shuliang Jiao Qinyan Li Fan zhang yonghong Tao Yingzhen Yu Fan Yao Qingmao Li Fengyi Hu Liyu Huang Key Laboratory of Biology and Germplasm Innovation of Perennial Rice Ministry of Agriculture and Rural Affairs/School of AgricultureYunnan UniversityKunming 650091China State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Wenshan Academy of Agricultural Sciences Wenshan 663000China

Semidwarf breeding has boosted crop production and is a well-known outcome from the first Green Revolution. The Green Revolution gene Semidwarf 1(SD1), which modulates gibberellic acid(GA) biosynthesis, plays a principal role in determining rice plant height. Mutations in SD1 reduce rice plant height and promote lodging resistance and fertilizer tolerance to increase grain production. The plant height mediated by SD1 also favors grain yield under certain conditions. However, it is not yet known whether the function of SD1 in upland rice promotes adaptation and grain production. In this study, the plant height and grain yield of irrigated and upland rice were comparatively analyzed under paddy and dryland conditions. In response to dryland environments, rice requires a reduction in plant height to cope with water deficits. Upland rice accessions had greater plant heights than their irrigated counterparts under both paddy and dryland conditions, and appropriately reducing plant height could improve adaptability to dryland environments and maintain high grain yield formation. Moreover, upland rice cultivars with thicker stem diameters had stronger lodging resistance, which addresses the lodging problem. Knockout of SD1 in the upland rice cultivar IRAT104 reduced the plant height and grain yield, demonstrating that the adjustment of plant height mediated by SD1 could increase grain production in dryland fields. In addition, an SD1 genetic diversity analysis verified that haplotype variation causes phenotypic variation in plant height. During the breeding history of rice, SD1 allelic mutations were selected from landraces to improve the grain yield of irrigated rice cultivars, and this selection was accompanied by a reduction in plant height. Thus, five known mutant alleles were analyzed to verify that functional SD1 is required for upland rice production. All these results suggest that SD1 might have undergone artificial positive selection in upland rice, which provides further insights concerning greater plant heigh

关键词： Green Revolution Semidwarf 1 high-yield breeding upland rice plant height

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Sustainable electrochemical dearomatization for the synthesis of diverse 2,3-functionalized indolines

Green Synthesis and Catalysis

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Green Synthesis and Catalysis 2024年第1期5卷 25-30页

作者： Jun Chen Rong zhang Caiyan Ma Peng zhang yonghong zhang Bin Wang Fei Xue Weiwei Jin Yu Xia Chenjiang Liu Urumqi Key Laboratory of Green Catalysis and Synthesis Technology Key Laboratory of Oil and Gas Fine ChemicalsMinistry of Education&Xinjiang Uygur Autonomous RegionState Key Laboratory of Chemistry and Utilization of Carbon Based Energy ResourcesCollege of ChemistryCollege of Future TechnologyXinjiang UniversityUrumqi 830017China

Herein,we achieved a green and efficient dearomatization for the synthesis of 2,3-functionalized polycyclic indolines in an electrochemical way.This avoiding of external oxidants and metals approach allowed various nucleophilic sources(Nu¼anilines,TMSN3 and ROH)to perform the products,representing an environmentally benign means.Additionally,the continuous flow electrosynthesis and synthetic transformations also reveal the strong practicality of electrochemistry in organic synthesis.

关键词： Green synthesis Organic electrochemistry Indole Dearomatization Cyclization

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Unique double-layer solid electrolyte interphase formed with fluorinated ether-based electrolytes for high-voltage lithium metal batteries

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Journal of Energy Chemistry 2024年第1期88卷 532-542,I0012页

作者： Ruo Wang Jiawei Li Bing Han Qingrong Wang Ruohong Ke Tong zhang Xiaohu Ao Guangzhao zhang Zhongbo Liu Yunxian Qian Fangfang Pan Iseult Lynch Jun Wang yonghong Deng Department of Materials Science&Engineering School of Innovation and EntrepreneurshipSouthern University of Science and TechnologyShenzhen 518055GuangdongChina School of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbastonBirmingham B152TTUK Key Laboratory of Marine Environmental Corrosion and Bio-Fouling Institute of OceanologyChinese Academy of SciencesQingdao 266071ShandongChina Shenzhen CAPCHEM Technology Co. Ltd.Shenzhen 518118GuangdongChina CALB Group Co. Ltd.Changzhou 213200JiangsuChina

Li metal batteries using high-voltage layered oxides cathodes are of particular interest due to their high energy density.However,they suffer from short lifespan and extreme safety concerns,which are attributed to the degradation of layered oxides and the decomposition of electrolyte at high voltage,as well as the high reactivity of metallic Li.The key is the development of stable electrolytes against both highvoltage cathodes and Li with the formation of robust interphase films on the surfaces.Herein,we report a highly fluorinated ether,1,1,1-trifluoro-2-[(2,2,2-trifluoroethoxy)methoxy]ethane(TTME),as a cosolvent,which not only functions as a diluent forming a localized high concentration electrolyte(LHCE),but also participates in the construction of the inner solvation structure.The TTME-based electrolyte is stable itself at high voltage and induces the formation of a unique double-layer solid electrolyte interphase(SEI)film,which is embodied as one layer rich in crystalline structural components for enhanced mechanical strength and another amorphous layer with a higher concentration of organic components for enhanced flexibility.The Li||Cu cells display a noticeably high Coulombic efficiency of 99.28%after 300 cycles and Li symmetric cells maintain stable cycling more than 3200 h at 0.5 mA/cm^(2) and 1.0m Ah/cm^(2).In addition,lithium metal cells using LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) and Li CoO_(2) cathodes(both loadings~3.0 m Ah/cm^(2))realize capacity retentions of>85%over 240 cycles with a charge cut-off voltage of 4.4 V and 90%for 170 cycles with a charge cut-off voltage of 4.5 V,respectively.This study offers a bifunctional ether-based electrolyte solvent beneficial for high-voltage Li metal batteries.

关键词： Lithium metal batteries High-voltage layered oxides Fluorinated ether-based electrolytes Solid electrolyte interphase Cathode electrolyte interphase

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Superior effectiveness and acceptability of saliva samples for the detection of SARS-CoV-2 in China

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Biosafety and Health 2024年第2期6卷 88-91页

作者： Hui Yao Ying Shen Zhichao Liang Xiaoyu Xue Chenxi Zhao Xiang Xu Yuxin Cai yonghong Liu Wei zhang Yang Pan Xiaoli Wang Bejing Office of Global Health Beijing Center for Disease Prevention and ControlBejing 100013China Institute for Infectious Disease and Endemic Disease Control Beijing Center for Disease Prevention and ControlBejing 100013China National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases Bejing Ditan HospitalCapital Medical UniversityBejing 100015China Center for Drug Evaluation National Medical Products AdministrationBejing 100176China School of Public Health Capital Medical UniversityBeijing 100069China

In response to problems of poor sampling quality,low sensitivity,and high demand for medical personnel regarding the current severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)oropharyngeal(OP)swab sampling used in China,we aimed to evaluate the diagnostic performance and acceptability of saliva-based nucleic acid amplification tests(NAATs)in China.The results showed that,using nasopharyngeal(NP)swab results as the gold standard,the overall sensitivities for saliva specimens and OP swabs were 93.3%and 85.0%,the specificities were 92.6%and 93.8%,respectively.The results of an acceptability survey showed that the scores for saliva,OP,and NP samples were 9.46±1.69,8.11±2.42,and 4.58±3.82 out of 10,respectively,with significant differences among the three groups(P

关键词： SARS-CoV-2 Saliva sample Sensitivity Acceptability

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Virtual source approach for maximizing resolution in high-penetration gamma-ray imaging

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Matter and Radiation at Extremes 2024年第3期9卷 19-30页

作者： Yuchi Wu Shaoyi Wang Bin Zhu yonghong Yan Minghai Yu Gang Li Xiaohui zhang Yue Yang Fang Tan Feng Lu Bi Bi Xiaoqin Mao Zhonghai Wang Zongqing Zhao Jingqin Su Weimin Zhou Yuqiu Gu National Key Laboratory of Plasma Physics Laser Fusion Research CenterCAEPMianyangSichuan 621900China College of Physics Sichuan UniversityChengdu 610065China

High-energy gamma-ray radiography has exceptional penetration ability and has become an indispensable nondestructive testing(NDT)tool in various fields.For high-energy photons,point projection radiography is almost the only feasible imaging method,and its spatial resolution is primarily constrained by the size of the gamma-ray source.In conventional industrial applications,gamma-ray sources are commonly based on electron beams driven by accelerators,utilizing the process of bremsstrahlung radiation.The size of the gamma-ray source is dependent on the dimensional characteristics of the electron beam.Extensive research has been conducted on various advanced accelerator technologies that have the potential to greatly improve spatial resolution in NDT.In our investigation of laser-driven gamma-ray sources,a spatial resolution of about 90μm is achieved when the areal density of the penetrated object is 120 g/cm^(2).A virtual source approach is proposed to optimize the size of the gamma-ray source used for imaging,with the aim of maximizing spatial resolution.In this virtual source approach,the gamma ray can be considered as being emitted from a virtual source within the convertor,where the equivalent gamma-ray source size in imaging is much smaller than the actual emission area.On the basis of Monte Carlo simulations,we derive a set of evaluation formulas for virtual source scale and gamma-ray emission angle.Under optimal conditions,the virtual source size can be as small as 15μm,which can significantly improve the spatial resolution of high-penetration imaging to less than 50μm.

关键词： resolution approach utilizing

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Tet methylcytosine dioxygenase 2(TET2)deficiency elicits EGFR-TKI(tyrosine kinase inhibitors)resistance in non-small cell lung cancer

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1706-1720页

作者： Jian zhang Kejia Zhao Wenjing Zhou Ran Kang Shiyou Wei Yueli Shu Cheng Yu Yin Ku yonghong Mao Hao Luo Juqin Yang Jiandong Mei Qiang Pu Senyi Deng Zhengyu Zha Gang Yuan Shensi Shen Yaohui Chen Lunxu Liu Department of Thoracic Surgery and Institute of Thoracic Oncology West China Hospital of Sichuan UniversityChengdu 610097China Western China Collaborative Innovation Center for Early Diagnosis and Multidisciplinary Therapy of Lung Cancer Sichuan UniversityChengdu 610097China Biobank of West China Hospital Sichuan UniversityChengdu 610041China

Despite epidermal growth factor receptor(EGFR)tyrosine kinase inhibitors(TKl)have shown remarkable efficacy in patients with EGFR-mutant non-small cell lung cancer(NSCLC),acquired resistance inevitably develops,limiting clinical efficacy.We found that TET2 was poly-ubiquitinated by E3 ligase CUL7^(FBXW11) and degraded in EGFR-TKI resistant NSCLC ells.Genetic perturbationof TET2 rendered parental cells more tolerant to TKI treatment.TET2 was stabilized by MEK1 phosphorylation at Ser 1107,while MEK1 inactivation promoted its proteasome degradation by enhancing the recruitment of CUL7^(FBXW11),Loss of TET2 resulted in the upregulation of TNF/NF-kB signaling that confers the EGFR-TKI resistance.Genetic or pharmacological inhibition of NF-kB attenuate the TKI resistance both in vitro and in vivo.Our findings exemplified how a cell growth controlling kinase MEK1 leveraged the epigenetic homeostasis by regulating TET2,and demonstrated an alternative path of non-mutational acquired EGFR-TKI resistance modulated by TET2 deficiency.Therefore,combined strategy exploiting EGFR-TKI and inhibitors of TET2/NF-κB axis holds therapeutic potential for treating NSCLC patients who suffered from this resistance.

关键词： TET2 TKI resistance

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