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Rheological Study of Polymers Used as Viscosity Index Improvers for Automotive Lubricant Oils
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作者 Ana Paula Pena Almeida Ana Paula Lelis Rodrigues de Oliveira +3 位作者 Cynthia D’ávila Carvalho Erbetta Ricardo Geraldo de Sousa Roberto Fernando de Souza Freitas Maria Elisa Scarpelli Ribeiro e Silva 《Journal of Modern Physics》 2014年第12期1085-1093,共9页
In this work, a rheological study of automotive lubricant oils, neutral light paraffinic (NLP) and neutral medium paraffinic (NMP), additivated with two commercial viscosity index improvers-VIIs, based on hydrogenated... In this work, a rheological study of automotive lubricant oils, neutral light paraffinic (NLP) and neutral medium paraffinic (NMP), additivated with two commercial viscosity index improvers-VIIs, based on hydrogenated poly (isoprene-co-styrene), at different concentrations, was carried out. The study included the determination of the kinematic viscosity of the mixtures, the calculation of the viscosity indexes and their behavior when subjected to various rheometric experiments, including stress sweep, steady state flow, creep and recovery, and temperature ramp oscillatory tests. The obtained results showed the efficacy of the additives as viscosity index improvers, enabling a significant increase in the viscosity index of the pure oils at relatively low concentrations. The determination of the storage (G’) and of the loss (G”) moduli for the mixtures oil/VII additives showed a large predominance of the viscous effect over the elastic one. Except when under low shear stress, the mixtures showed a pseudoplastic behavior, with the flow curves being adjusted to fit the Ostwald-de-Waele model (Power Law), with negative flow behavior indexes. 展开更多
关键词 VISCOSITY INDEX improvers AUTOMOTIVE Lubricants RHEOLOGY VISCOSITY INDEX Polymer ADDITIVES
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Co-adsorption behaviors of asphaltenes and different flow improvers and their impacts on the interfacial viscoelasticity 被引量:2
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作者 Hao Zhang Daiwei Liu +5 位作者 Jiangbo Wen Guangyu Sun Chuanxian Li Xinya Chen Huihui Zhang Ze Duan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第8期149-157,共9页
Commonly used flow improvers in oilfields,such as ethylene–vinyl acetate copolymer(EVA),poly(octadecyl acrylate)(POA),and polymethylsilsesquioxane(PMSQ)are proven to be effective to enhance the flowability of crude o... Commonly used flow improvers in oilfields,such as ethylene–vinyl acetate copolymer(EVA),poly(octadecyl acrylate)(POA),and polymethylsilsesquioxane(PMSQ)are proven to be effective to enhance the flowability of crude oil.However,the addition of these flow improvers may change the stability of the emulsion and make the crude oil treatment process challenging.In this research,the impacts of different flow improvers on the interfacial properties of the emulsions containing asphaltenes are systematically investigated.The co-adsorption behaviors of the flow improvers and asphaltenes are analyzed through dynamic interfacial tension(DIFT).The rheological properties of the interfacial layer after the adsorption are explored via dilational viscoelasticity.Significant difference is observed in the structural properties of the interface adsorbed by different flow improvers,which is attributed to different interactions between the flow improvers and asphaltenes.To investigate these interactions,conductivity,asphaltenes precipitation,dynamic light scattering(DLS),and contact angle experiments are conducted systematically.Results show that EVA and POA can alter the interfacial properties by changing the asphaltene dispersion state.The interaction between EVA and asphaltenes is stronger than that between POA and asphaltenes due to the difference in molecular structures.Unlike EVA and POA,the change of interfacial property with the addition of PMSQ is attributed to the partial adsorption of asphaltenes on PMSQ. 展开更多
关键词 ASPHALTENE Flow improver Interfacial tension Interfacial rheology Emulsions Adsorption
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How Polymers Behave as Viscosity Index Improvers in Lubricating Oils 被引量:5
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作者 Michael J. Covitch Kieran J. Trickett 《Advances in Chemical Engineering and Science》 2015年第2期134-151,共18页
One of the requirements of engine lubricating oil is that it must have a low enough viscosity at low temperatures to assist in cold starting and a high enough viscosity at high temperatures to maintain its load-bearin... One of the requirements of engine lubricating oil is that it must have a low enough viscosity at low temperatures to assist in cold starting and a high enough viscosity at high temperatures to maintain its load-bearing characteristics. Viscosity Index (VI) is one approach used widely in the lubricating field to assess the variation of viscosity with temperature. The VI of both mineral and synthetic base oils can be improved by the addition of polymeric viscosity modifiers (VMs). VI improvement by VMs is widely attributed to the polymer coil size expanding with increasing temperature. However, there is very little physical data supporting this generally accepted mechanism. To address this issue, intrinsic viscosity measurements and Small-Angle Neutron Scattering (SANS) have been used to study the variation of polymer coil size with changing temperature and concentration in a selection of solvents. The results will show that coil size expansion with temperature is not necessary to achieve significant elevation of viscosity index. 展开更多
关键词 VISCOSITY Index IMPROVER VISCOSITY MODIFIER Polymer SMALL-ANGLE NEUTRON Scattering RHEOLOGY
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Aminated Copolymers as Flow Improvers for Super-viscous Crude Oils 被引量:1
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作者 Zhang Hong Shen Benxian 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2007年第3期43-49,共7页
The new flow improvers for super-viscous crude oils were developed via esterification of polybasic high carbon alcohol with methacrylate and copolymerizafion of monomers followed by amination of copolymers. The struct... The new flow improvers for super-viscous crude oils were developed via esterification of polybasic high carbon alcohol with methacrylate and copolymerizafion of monomers followed by amination of copolymers. The structure of the synthesized polymer flow improver additive was confirmed by IR spectroscopy and the crystal structure of the flow improver additives were determined by X-ray diffrac- tion analysis. The structure of wax crystals was also studied at the same time. The results showed that the wax crystal structure was closely related with the crystal structure of the flow improver, which could change the pour point depression and viscosity reduction behavior of the crude oil. When the wax crystal structure matched well with that of the additive, the wax crystals were dispersed satisfactorily, resulting in favorable effects in terms of pour point depression and viscosity reduction. The new synthe- sized aminated polymer flow improver additive was most efficient for treating super-viscous crude oils. The super-viscous crude oil had a high content of resins and asphaltenes, which might aggregate onto the surface of wax crystals to form blocks to limit the crude oil fluidity. However, amination of copolymers having similar structure with the resins and asphaltenes contained in crude oil could dissolve the huge polar groups to make the deposit formation difficult. 展开更多
关键词 aminated copolymers flow improver super-viscous crude oil
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National development requires the younger generation to cultivate the standardization consciousness and mindset
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作者 Zhang Xiaogang 《China Standardization》 2026年第1期42-42,共1页
The International Standardization Youth Star Competition is held for three consecutive years.We have witnessed continuous improvement in the competition each year,which is a result of our collective efforts.
关键词 collective efforts youth competition national development improvement standardization consciousness
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Stakeholder partnership in the development of standardization activities
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作者 Zaki Al-Rubaei 《China Standardization》 2026年第1期24-29,共6页
Introduction:The choice is no longer whether—but when and how!Today,organizations can no longer choose whether or not to engage with stakeholders;the only real decision is when and how to do it successfully.Engaging ... Introduction:The choice is no longer whether—but when and how!Today,organizations can no longer choose whether or not to engage with stakeholders;the only real decision is when and how to do it successfully.Engaging stakeholders is essential for any type of organization,public,private,or civil society.In fact,it is a fundamental part of effective governance,continuous improvement,and social responsibility.The principle behind stakeholder engagement is simple yet powerful:those who can influence or be affected by an organization's mission must be given the opportunity to express their views and contribute to shaping the decisions that impact them. 展开更多
关键词 standardization activities continuous improvement stakeholder engagement effective governancecontinuous social responsibility engage stakeholdersthe governance
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Thanks to our reviewers in 2025
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《International Journal of Nursing Sciences》 2026年第1期I0007-I0007,共1页
Many reviewers contributed their insights and advice to the International Journal of Nursing Sciences in 2025,along with suggestions for improving manuscripts that were submitted for publication.These peer reviewers,l... Many reviewers contributed their insights and advice to the International Journal of Nursing Sciences in 2025,along with suggestions for improving manuscripts that were submitted for publication.These peer reviewers,listed below,have generously given their time and wisdom.The editorial team is grateful to all colleagues who have participated in this worthwhile endeavour. 展开更多
关键词 peer reviewers manuscript improvement nursing sciences peer reviewerslisted international journal editorial team
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WRKY53:A Key Player in Stress Responses and Growth Regulation in Rice
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作者 AN Shuaizu LÜJun +4 位作者 MA Zemin GAO Xuanlin ZHANG Biaoming YANG Pingfang KE Yinggen 《Rice science》 2026年第1期30-38,共9页
As sessile organisms,plants must adapt various stresses.Accordingly,they have evolved several plant-specific growth and developmental processes.WRKY53 is a member of the WRKY transcription factor family,which plays a ... As sessile organisms,plants must adapt various stresses.Accordingly,they have evolved several plant-specific growth and developmental processes.WRKY53 is a member of the WRKY transcription factor family,which plays a crucial role in rice growth and development,stress response,and hormone signal transduction.This review discusses the role of WRKY53 in stress response,focusing on its functions in cold tolerance,salt tolerance,disease resistance,and pest defense,and explores its role in regulating rice leaf senescence and seed germination.This article also proposes future research directions,including functional genomics studies,protein interaction network analyses,hormone signal transduction pathways,genetic improvement strategies,applications of gene editing technologies,molecular basis of stress responses,cross-species functional conservation,and bioinformatics and comparative genomics research.This review highlights the importance of WRKY53 in rice biology and provides new perspectives and strategies for future research and genetic improvement of rice. 展开更多
关键词 WRKY53 RICE stress response signal transduction growth and development genetic improvement
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Water vapor signals and climate influences in northeastern China:insights from tree-rings and precipitationδ^(18)O
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作者 Jiachuan Wang Qiang Li +12 位作者 Yu Liu Meng Ren Zichun Jia Yifan Wu Yang Xu Jeong-Wook Seo Changfeng Sun Huiming Song Qiufang Cai Zhenchuan Niu Wenxuan Pang Xiangyu Duan Wentai Liu 《Journal of Forestry Research》 2026年第2期144-157,共14页
The northeastern permafrost region of China is one of the most vulnerable areas to climate warming in midlatitude areas.Despite this,the specific pathways of water vapor circulation and transport in this area remain p... The northeastern permafrost region of China is one of the most vulnerable areas to climate warming in midlatitude areas.Despite this,the specific pathways of water vapor circulation and transport in this area remain poorly understood.Additionally,there is ongoing debate on whether the oxygen isotope of precipitation(δ^(18)O_(p))is primarily influenced by the temperature or the precipitation amount effects.Tree-ring samples were collected from various sites and tree species across the region,and 12 stable oxygen isotopes(δ18Oc)series constructed to investigate the water vapor signals embedded within.Our findings revealed consistentδ18Oc variations across different sites and species,reflecting relative humidity signals during the growing season(June to September)(r=−0.764,P<0.001,n=40).By applying an improved model to simulateδ^(18)O_(p),a“temperature effect”was identified.Bothδ18Oc andδ^(18)O_(p) provided valuable insights into the regional water vapor circulation,withδ18Oc offering a stronger climate signal.A binary linear regression model further revealed thatδ^(18)O_(p) had a greater influence onδ18Oc than relative humidity.The regional climate is primarily driven by the East Asian summer monsoon and large-scale water vapor circulation associated with the El Niño-Southern Oscillation.Because of future warming and drying trends,trees in this region are expected to face increasing drought stress. 展开更多
关键词 Tree-ring oxygen isotopes Precipitation oxygen isotopes Improved model Permafrost region
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Investigation of natural and anthropogenic effects on aerosols optical properties over the Western Pacific ocean by the research vessel KEXUE
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作者 Jinyuan Xin Yining Ma +6 位作者 Xiangguang Zhang Yongjing Ma Xiaoyan Wu Fangkun Wu Quan Liu Yilong Lyu Jiawei Jiang 《Journal of Environmental Sciences》 2026年第1期596-605,共10页
In winter 2018,an aerosol physicochemical experiment was conducted in the Western Pacific Ocean(WPO)aboard the Research Vessel KEXUE of Chinese Academy of Sciences.This study systematically investigated both natural a... In winter 2018,an aerosol physicochemical experiment was conducted in the Western Pacific Ocean(WPO)aboard the Research Vessel KEXUE of Chinese Academy of Sciences.This study systematically investigated both natural and anthropogenic effects on marine aerosols optical properties,as well as the applicability of multi-satellite products and IMPROVE equation.The averaged aerosol optical depth(AOD500 nm)was 0.31±0.16 andÅngström exponent440–675 nm was 0.29±0.30.In offshore China,significant anthropogenic emissions affected the marine environment.In remote WPO,dust aerosols transported from northern China,Siberia,Central Asia,and those settling from the upper troposphere originating from north Africa,Arabian peninsula,and western India,were dominant.The spatial trends of AOD were opposite in the mid-latitude and southern seas of WPO.The highest AOD,0.32±0.23,appeared along the coast of South Asia at mid-latitude,decreasing from offshore seas to remote oceans.In low-latitude and equatorial seas,AOD significantly increased from coast to remote oceans.Ångström exponent dropped significantly from the coast to remote oceans as anthropogenic influence diminished across the entire WPO.Correlation analysis showed that both MODIS-C6 and Himawari AOD prod-ucts showed similar applicability in coastal urban areas,while Himawari AOD is highly recommended for coastal background and marine environment due to its finer resolution.The extinction coefficient derived from PM_(2.5) chemical compositions using IMPROVE algorithm exhibited a significant correlation(R^(2)=0.58)with the con-currently measured AOD in the absence of long-distance transport,suggesting that the IMPROVE is a reasonable proxy of the columnar average of marine aerosol extinctions free from transport influences. 展开更多
关键词 Aerosol optical properties Natural and anthropogenic effects Improve algorithm Ship-borne experiment Western Pacific Ocean
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In Japan Prospects for Introducing IBCTL at Graduate School of Teacher Education to Advance the Teaching Profession and Foster OECD Student Agency:Considerations for Curriculum Development and Syllabus Creation
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作者 Kenji Shigeno 《Cultural and Religious Studies》 2026年第1期1-12,共12页
The purpose of this study is to gain perspectives on introducing IBCTL(International Baccalaureate Certificate in Teaching and Learning)into graduate school of teacher education in Japan,which are currently providing ... The purpose of this study is to gain perspectives on introducing IBCTL(International Baccalaureate Certificate in Teaching and Learning)into graduate school of teacher education in Japan,which are currently providing advanced teacher training programs aimed at cultivating student agency,a comprehensive set of skills necessary for children living in the future,as advocated by the Organisation for Economic Co-operation and Development(OECD)Education 2030 Project.To achieve this goal,I examined the curriculum and structure that are important for IB teacher training and the introduction of IBCTL.I attempted to achieve this goal by examining the curriculum being developed at a graduate school of teacher education attempting to implement IBCTL and the creation of a syllabus based on that curriculum through lesson planning.As a result,I examined the curriculum and structure as a perspective for introducing IBCTL into graduate school of teacher education in Japan,where advanced teacher training is required.I found that a core curriculum and structure that incorporates the core of the IBCTL into the core of graduate school of teacher education programs is important for implementing an IB education that is aligned with the advancement of teacher training and the development of student agency. 展开更多
关键词 graduate school of education IBCTL OECD student agency core curriculum improving teacher training
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Comparative Analysis of the Growth-promoting Effects of Three Endophytic Bacteria on the Medicinal Plant Emilia prenanthoidea DC.
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作者 Xiaoqian XIONG Xiaojian GONG +4 位作者 Tianhua YU Xue YANG Wanyun WU Zhannan YANG Chao ZHAO 《Medicinal Plant》 2026年第1期30-33,39,共5页
[Objectives]To assess the effects of endophytic bacteria on the growth,antioxidant responses,and the production of key secondary metabolites in Emilia prenanthoidea DC.[Methods]Three endophytic strains(H1,H2,L1)were i... [Objectives]To assess the effects of endophytic bacteria on the growth,antioxidant responses,and the production of key secondary metabolites in Emilia prenanthoidea DC.[Methods]Three endophytic strains(H1,H2,L1)were inoculated onto tissue-cultured seedlings and cultivated for 20 d under greenhouse conditions.Growth traits,reactive oxygen species(ROS)indicators,antioxidant enzyme activities,and the content of chlorogenic acid and quercetin were analyzed using one-way ANOVA followed by Tukey s test.[Results]Bacterial inoculation significantly enhanced plant performance.Treatment H2 increased plant height by 27%,chlorophyll content by 73%,and fresh weight by 31%.Levels of ROS(O^(-)_(2),H_(2)O_(2))and MDA decreased markedly,whereas the activities of POD and CAT increased.Additionally,the content of chlorogenic acid and quercetin increased by up to 67%and 64%,respectively,with both H2 and L1 treatments showing the most pronounced effects.[Conclusions]Endophytic bacteria markedly improve growth,redox balance,and phenolic accumulation in E.prenanthoidea.Strain H2 represents a promising bioinoculant for improving the medicinal quality of this species. 展开更多
关键词 Endophytic bacteria Emilia prenanthoidea DC. Plant growth promotion Flavonoid metabolism Antioxidant enzymes ROS homeostasis Medicinal plant improvement
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Entropy regulation induced hollow prismatic structural NiCoFeInZnV-based layered double hydroxide with prominent electrochemical kinetics and stability for aqueous zinc-ion batteries
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作者 Liu Yang Tao Zou +9 位作者 Haihui Wu Jiqing Zhang Xuekun Sui Wenjing Zhang Ende Feng Xiaohui Guan Bao Liu Jingru Bai Penggang Yin Guangsheng Wang 《Journal of Energy Chemistry》 2026年第1期274-283,I0007,共11页
Layered double hydroxides(LDHs)hold great promise as cathode materials for aqueous zinc-ion batteries(AZIBs).Nevertheless,they also face challenges of sluggish kinetics and rapid capacity loss.Herein,a conformational ... Layered double hydroxides(LDHs)hold great promise as cathode materials for aqueous zinc-ion batteries(AZIBs).Nevertheless,they also face challenges of sluggish kinetics and rapid capacity loss.Herein,a conformational entropy regulation strategy has been applied to surmount the shortcomings.A medium-entropy iron-based metal organic framework(MIL-88)derived NiCoFeInZnV-based layered double hydroxide with carbon loaded(ME-NiCoFeInZnV-LDH/C)has been first proposed and prepared with a designed method.The increased entropy optimizes electron conductivity and alleviates structure alteration and diffusion barrier during interactions with charge carriers,due to electron-induced effect and“cocktail”effect.Moreover,the nanosheet assembled hollow prismatic structures could homogenize flux distribution and electric field distribution.Therefore,the electrochemical kinetics,crystal structure stability,and activity could be dramatically improved.Leveraging the advantages of structure and composition regulation,Zn||ME-NiCoFeInZnV-LDH/C zinc battery delivers high specific capacities,rate performance,and cycling stability.This work proposes a novel and feasible medium-entropy strategy to prepare a high-performance cathode for advanced AZIBs,which is of prominent significance for the development of charge storage devices. 展开更多
关键词 Medium-entropy strategy ME-NiCoFeInZnV-LDH/C Nanosheet assembled hollow prismatic structures Aqueous zinc-ion batteries Improved electrochemical kinetics and activity
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An enhanced segmentation method for 3D point cloud of tunnel support system using PointNet++t and coverage-voted strategy algorithms
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作者 Wenju Liu Fuqiang Gao +4 位作者 Shuangyong Dong Xiaoqing Wang Shuwen Cao Wanjie Wang Xiaomin Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1653-1660,共8页
3D laser scanning technology is widely used in underground openings for high-precision,rapid,and nondestructive structural evaluations.Segmenting large 3D point cloud datasets,particularly in coal mine roadways with m... 3D laser scanning technology is widely used in underground openings for high-precision,rapid,and nondestructive structural evaluations.Segmenting large 3D point cloud datasets,particularly in coal mine roadways with multi-scale targets,remains challenging.This paper proposes an enhanced segmentation method integrating improved PointNet++with a coverage-voted strategy.The coverage-voted strategy reduces data while preserving multi-scale target topology.The segmentation is achieved using an enhanced PointNet++algorithm with a normalization preprocessing head,resulting in a 94%accuracy for common supporting components.Ablation experiments show that the preprocessing head and coverage strategies increase segmentation accuracy by 20%and 2%,respectively,and improve Intersection over Union(IoU)for bearing plate segmentation by 58%and 20%.The accuracy of the current pretraining segmentation model may be affected by variations in surface support components,but it can be readily enhanced through re-optimization with additional labeled point cloud data.This proposed method,combined with a previously developed machine learning model that links rock bolt load and the deformation field of its bearing plate,provides a robust technique for simultaneously measuring the load of multiple rock bolts in a single laser scan. 展开更多
关键词 Point cloud segmentation Improved PointNet++ Tunnel laser scanning Rock bolt automatic recognition
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Optimal reactive power planning in an industrial microgrid:a case study of Urmia Petrochemical plant
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作者 Maryam Majidzadeh Mostafa Esmaeeli +2 位作者 Hadi Afkar Sajjad Golshannavaz Zhiyi Li 《Global Energy Interconnection》 2026年第1期208-218,共11页
In real industrial microgrids(MGs),the length of the primary delivery feeder to the connection point of the main substation is sometimes long.This reduces the power factor and increases reactive power absorption along... In real industrial microgrids(MGs),the length of the primary delivery feeder to the connection point of the main substation is sometimes long.This reduces the power factor and increases reactive power absorption along the primary delivery feeder from the external network.Besides,the giant induction electro-motors as the working horse of industries requires remarkable amounts of reactive power for electro-mechanical energy conversions.To reduce power losses and operating costs of the MG as well as to improve the voltage quality,this study aims at providing an insightful model for optimal placement and sizing of reactive power compensation capacitors in an industrial MG.In the presented model,the objective function considers voltage profile and network power factor improvement at the MG connection point.Also,it realizes power flow equations within which all operational security constraints are considered.Various reactive power compensation strategies including distributed group compensation,centralized compensation at the main substation,and distributed compensation along the primary delivery feeder are scrutinized.A real industrial MG,say as Urmia Petrochemical plant,is considered in numerical validations.The obtained results in each scenario are discussed in depth.As seen,the best performance is obtained when the optimal location and sizing of capacitors are simultaneously determined at the main buses of the industrial plants,at the main substation of the MG,and alongside the primary delivery feeder.In this way,74.81%improvement in power losses reduction,1.3%lower active power import from the main grid,23.5%improvement in power factor,and 37.5%improvement in network voltage deviation summation are seen in this case compared to the base case. 展开更多
关键词 Reactive power compensation Shunt capacitor Optimal placement and sizing Voltage profile improvement Power factor correction
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From seed to whole plant:An innovative visual marker system to enhance selection efficiency in soybean genome editing
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作者 Tingwei Yan Xueyan Qian +5 位作者 Hong Pan Jiarui Han Qi Wang Chang Liu Dongquan Guo Xiangguo Liu 《Journal of Integrative Agriculture》 2026年第2期820-823,共4页
Emerging and powerful genome editing tools,particularly CRISPR/Cas9,are facilitating functional genomics research and accelerating crop improvement(Jiang et al.2021;Cao et al.2023;Chen C et al.2023;Liu et al.2023a).Ho... Emerging and powerful genome editing tools,particularly CRISPR/Cas9,are facilitating functional genomics research and accelerating crop improvement(Jiang et al.2021;Cao et al.2023;Chen C et al.2023;Liu et al.2023a).However,the detection and screening of transgenic lines remain major bottlenecks,being time-consuming,labor-intensive,and inefficient during transformation and subsequent mutation identification.A simple and efficient visual marker system plays a critical role in addressing these challenges.Recent studies demonstrated that the GmW1 and RUBY reporter systems were used to obtain visual transgenic soybean(Glycine max) plants(Chen L et al.2023;Chen et al.2024). 展开更多
关键词 accelerating crop improvement jiang mutation identificationa enhance selection efficiency SEED functional genomics research detection screening transgenic lines genome editing toolsparticularly innovative visual marker system
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Magnetic stagnation of two counterstreaming plasma jets induced by intense laser
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作者 R.S.Zemskov S.E.Perevalov +16 位作者 A.V.Kotov A.A.Murzanev A.I.Korytin K.F.Burdonov V.N.Ginzburg A.A.Kochetkov S.E.Stukachev I.V.Yakovlev I.A.Shaikin A.A.Kuzmin E.V.Derishev A.V.Korzhimanov A.A.Soloviev A.A.Shaykin A.N.Stepanov M.V.Starodubtsev E.A.Khazanov 《Matter and Radiation at Extremes》 2026年第1期46-57,共12页
Experiments with interacting high-velocity flows in a laser plasma can help answer fundamental questions in plasma physics and improve understanding of the mechanisms behind some astrophysical phenomena,such as the fo... Experiments with interacting high-velocity flows in a laser plasma can help answer fundamental questions in plasma physics and improve understanding of the mechanisms behind some astrophysical phenomena,such as the formation of collisionless shock waves,deceleration of accretion flows,and evolution of solar and stellar flares.This work presents the first direct experimental observations of stagnation and redirection of counterstreaming flows(jets)of laser plasma induced by intense laser pulses with intensity I~2×10^(18) W/cm^(2).Hybrid particlein-cell-fluid modeling,which takes into account the kinetic effects of ion motion and the evolution of the pressure tensor for electrons,demonstrates the compression of counterdirected toroidal self-generated magnetic fields embedded in counterstreaming plasma flows.The enhancement of the toroidal magnetic field in the interaction region results in plasma flow stagnation and redirection of the jets across the line of their initial propagation. 展开更多
关键词 improve understanding mechanisms redirection counterstreaming evolution solar stellar flaresthis laser plasma intense laser pulses astrophysical phenomenasuch collisionless shock wavesdeceleration accretion flowsand answer fundamental questions plasma physics
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Synergistic mechanism of corn steep liquor and myo-inositol co-application in alleviating salt stress in Chinese cabbage
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作者 Xinjun Zhang Fengbo Ma +5 位作者 Xiaojing Ma Jiahong Zuo Xueming Fan Kangguo Mu Wenna Zhang Qing Chen 《Horticultural Plant Journal》 2026年第1期207-211,共5页
Salinization of agricultural land is becoming increasingly severe worldwide,posing a significant threat to food security.The exogenous application of bioactive substances has been widely used to enhance plant resistan... Salinization of agricultural land is becoming increasingly severe worldwide,posing a significant threat to food security.The exogenous application of bioactive substances has been widely used to enhance plant resistance to salt stress.In this study,we used corn steep liquor(CSL),myo-inositol(MI),and their combination to improve salt tolerance in Chinese cabbage(Brassica rapa L.ssp.pekinensis)under salt stress conditions.All three treatments significantly increased plant biomass and nutrient uptake,and improved soil physicochemical properties,while alleviating oxidative damage and ion toxicity. 展开更多
关键词 corn steep liquor exogenous application bioactive substances improve salt tolerance chinese cabbage brassica enhance plant resistance salt stressin salt stress corn steep liquor csl myo inositol mi myo inositol
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Terpolymers of alkyl methacrylate-trans anethole-1,2,3,6-tetrahydrophthalic anhydride copolymers:A low dosage and high-efficiency cold flow improver for diesel fuel
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作者 Bowen Xu Jiahao Chen +3 位作者 Lulu Cui Xinyue Li Yuan Xue Sheng Han 《Chinese Chemical Letters》 2025年第5期606-609,共4页
The addition of cold flow improvers(CFIs)is considered as the optimum strategy to improve the cold flow properties(CFPs)of diesel fuels,but this strategy is always limited by the required large dosage.To obtain low-do... The addition of cold flow improvers(CFIs)is considered as the optimum strategy to improve the cold flow properties(CFPs)of diesel fuels,but this strategy is always limited by the required large dosage.To obtain low-dosage and high-efficiency CFIs for diesel,1,2,3,6-tetrahydrophthalic anhydride(THPA)was introduced as a third and polar monomer to enhance the depressive effects of alkyl methacrylatetrans anethole copolymers(C_(14)MC-TA).The terpolymers of alkyl methacrylate-trans anethole-1,2,3,6-tetrahydrophthalic anhydride(C_(14)MC-TA-THPA)were synthesized and compared with the binary copolymers of C_(14)MC-TA and alkyl methacrylate-1,2,3,6-tetrahydrophthalic anhydride(C_(14)MC-THPA).Results showed that C_(14)MC-THPA achieved the best depressive effects on the cold filter plugging point(CFPP)and solid point(SP)by 11℃and 16℃at a dosage of 1250 mg/L and monomer ratio of 6:1,while 1500mg/L C_(14)MC-TA(1:1)reached the optimal depressive effects on the CFPP and SP by 12℃and 18℃.THPA introduction significantly improved the depressive effects of C_(14)MC-TA.Lower dosages of C_(14)MCTA-THPA in diesel exerted better improvement effects on the CFPP and SP than that of C_(14)MC-TA and C_(14)MC-THPA.When the monomer ratio and dosage were 6:0.6:0.4 and 1000 mg/L,the improvement effect of C_(14)MC-TA-THPA on diesel reached the optimum level,and the CFPP and SP were reduced by 13℃and 19℃,respectively.A 3D nonlinear surface diagram fitted by a mathematical model was also used for the first time to better understand the relationships of monomer ratios,dosages,and depressive effects of CFIs in diesel.Surface analysis results showed that C_(14)MC-TA-THPA achieved the optimum depressive effects at a monomer ratio of 6:0.66:0.34 and dosage of 1000 mg/L,and the CFPP and SP decreased by 14℃ and 19℃,respectively.The predicted results were consistent with the actual ones.Additionally,the improvement mechanism of these copolymers in diesel was also explored. 展开更多
关键词 Diesel fuel High-efficiency Cold flow properties Cold flow improvers Mathematical model
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Application of the improved dung beetle optimizer,muti-head attention and hybrid deep learning algorithms to groundwater depth prediction in the Ningxia area,China 被引量:1
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作者 Jiarui Cai Bo Sun +5 位作者 Huijun Wang Yi Zheng Siyu Zhou Huixin Li Yanyan Huang Peishu Zong 《Atmospheric and Oceanic Science Letters》 2025年第1期18-23,共6页
Due to the lack of accurate data and complex parameterization,the prediction of groundwater depth is a chal-lenge for numerical models.Machine learning can effectively solve this issue and has been proven useful in th... Due to the lack of accurate data and complex parameterization,the prediction of groundwater depth is a chal-lenge for numerical models.Machine learning can effectively solve this issue and has been proven useful in the prediction of groundwater depth in many areas.In this study,two new models are applied to the prediction of groundwater depth in the Ningxia area,China.The two models combine the improved dung beetle optimizer(DBO)algorithm with two deep learning models:The Multi-head Attention-Convolution Neural Network-Long Short Term Memory networks(MH-CNN-LSTM)and the Multi-head Attention-Convolution Neural Network-Gated Recurrent Unit(MH-CNN-GRU).The models with DBO show better prediction performance,with larger R(correlation coefficient),RPD(residual prediction deviation),and lower RMSE(root-mean-square error).Com-pared with the models with the original DBO,the R and RPD of models with the improved DBO increase by over 1.5%,and the RMSE decreases by over 1.8%,indicating better prediction results.In addition,compared with the multiple linear regression model,a traditional statistical model,deep learning models have better prediction performance. 展开更多
关键词 Groundwater depth Multi-head attention Improved dung beetle optimizer CNN-LSTM CNN-GRU Ningxia
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