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Perfluorooctanoic acid(PFOA) and perfluorooctanesulfonic acid(PFOS) concentrations in the South Korean agricultural environment: A national survey 被引量:1
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作者 Geun-Hyoung Choi Deuk-Young Lee +4 位作者 Dong-Kyu Jeong Saranya Kuppusamy Yong Bok Lee Byung-Jun Park Jin-Hyo Kim 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第8期1841-1851,共11页
Research on the occurrence of perfluorochemicals (PFCs) such as perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in the agricultural environment is lacking, in spite of their potential risk ... Research on the occurrence of perfluorochemicals (PFCs) such as perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in the agricultural environment is lacking, in spite of their potential risk via food chain transfer from aquatic and soil-plant systems to animals and/or humans. In the present study, for the first time, soil and water samples collected from 243 different agricultural sites adjacent to waste water treatment plants (WWTPs) belonging to 81 cities and 5 provinces with different levels of industrialization in South Korea were monitored for concentrations of PFOS and PFOA by use of solid phase extraction and liquid chromatography-tandem mass spectroscopy (LC-MS/MS). Significant mean concentrations of PFOA (0.001-0.007 tJg L-1 water and 〈0.05-1.573 tJg kg-1 soil) and PFOS (0.001-0.22 tJg L-1 water and 〈0.05-0.741 pg kg-1 soil) were found in all samples. Concentrations of PFCs in soils were high, highlighting that soil is an important sink for PFCs in the agricultural environment. Samples from near WWTPs in Gyeongsang Province contained the highest concentrations of PFOS and PFOA, reflecting the concentration of heavy industry in the province. The concentrations of PFCs in agricultural water (most samples 〈0.05 pg L-~) and soils (most samples 〈1 IJg kg-~) from South Korea were less than acceptable guideline values, indicating that South Korea is not a hotspot of PFOS and PFOA contamination and that there is negligible risk to human and ecological health from these chemicals. However, further studies investigating the seasonal variation in PFOA, PFOS and other perfluorochemical concentrations in the agricultural environment are needed. 展开更多
关键词 PFOS PFOA agricultural environment residual concentration South Korea
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Electrokinetic-mechanism of water and furfural oxidation on pulsed laser-interlaced Cu_(2)O and CoO on nickel foam 被引量:1
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作者 Yewon Oh Jayaraman Theerthagiri +3 位作者 M.L.Aruna Kumari Ahreum Min Cheol Joo Moon Myong Yong Choi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期145-154,共10页
The electrocatalytic oxidation of biomass-derived furfural(FF)feedstocks into 2-furoic acid(FA)holds immense industrial potential in optics,cosmetics,polymers,and food.Herein,we fabricated Co O/Ni O/nickel foam(NF)and... The electrocatalytic oxidation of biomass-derived furfural(FF)feedstocks into 2-furoic acid(FA)holds immense industrial potential in optics,cosmetics,polymers,and food.Herein,we fabricated Co O/Ni O/nickel foam(NF)and Cu_(2)O/Ni O/NF electrodes via in situ pulsed laser irradiation in liquids(PLIL)for the bifunctional electrocatalysis of oxygen evolution reaction(OER)and furfural oxidation reaction(FOR),respectively.Simultaneous oxidation of NF surface to NiO and deposition of CoO and/or Cu_(2)O on NF during PLIL offer distinct advantages for enhancing both the OER and FOR.CoO/NiO/NF electrocatalyst provides a consistently low overpotential of~359 m V(OER)at 10 m A/cm^(2),achieving the maximum FA yield(~16.37 m M)with 61.5%selectivity,79.5%carbon balance,and a remarkable Faradaic efficiency of~90.1%during 2 h of FOR at 1.43 V(vs.reversible hydrogen electrode).Mechanistic pathway via in situ electrochemical-Raman spectroscopy on CoO/NiO/NF reveals the involvement of phase transition intermediates(NiOOH and CoOOH)as surface-active centers during electrochemical oxidation.The carbonyl carbon in FF is attacked by hydroxyl groups to form unstable hydrates that subsequently undergo further oxidation to yield FA products.This method holds promise for large-scale applications,enabling simultaneous production of renewable building materials and fuel. 展开更多
关键词 Pulsed laser irradiation in liquids Water and furfural oxidation In situ Raman spectroscopy CoO/NiO/nickel foam Cu_(2)O/Nio/nickel foam 2-furoic acid
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Sustainable Furfural Biomass Feedstocks Electrooxidation toward Value-Added Furoic Acid with Energy-Saving H_(2) Fuel Production Using Pt-Decorated Co_(3)O_(4) Nanospheres 被引量:1
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作者 Talshyn Begildayeνa Jayaraman Theerthagiri +4 位作者 Seung Jun Lee Ahreum Min Gyeong-Ah Kim Siνakumar Manickam Myong Yong Choi 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期350-358,共9页
Here,furfural oxidation was performed to replace the kinetically sluggish O_(2)evolution reaction(OER).Pt-Co_(3)O_(4)nanospheres were developed via pulsed laser ablation in liquid(PLAL)in a single step for the paired ... Here,furfural oxidation was performed to replace the kinetically sluggish O_(2)evolution reaction(OER).Pt-Co_(3)O_(4)nanospheres were developed via pulsed laser ablation in liquid(PLAL)in a single step for the paired electrocatalysis of an H_(2)evolution reaction(HER)and furfural oxidation reaction(FOR).The FOR afforded a high furfural conversion(44.2%)with a major product of 2-furoic acid after a 2-h electrolysis at 1.55 V versus reversible hydrogen electrode in a 1.0-M KOH/50-mM furfural electrolyte.The Pt-Co_(3)O_(4)electrode exhibited a small overpotential of 290 mV at 10 mA cm^(-2).As an anode and cathode in an electrolyzer system,the Pt-Co_(3)O_(4)electrocatalyst required only a small applied cell voltage of~1.83 V to deliver 10 mA cm^(-2),compared with that of the pure water electrolyzer(OER||HER,~1.99 V).This study simultaneously realized the integrated production of energy-saving H_(2)fuel at the cathode and 2-furoic acid at the anode. 展开更多
关键词 biomass conversion electrochemical furfural oxidation overall water splitting Pt-Co_(3)O_(4)electrocatalyst pulsed laser ablation in liquid
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Pulsed laser interference patterning of transition-metal carbides for stable alkaline water electrolysis kinetics
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作者 Yewon Oh Jayaraman Theerthagiri +3 位作者 Ahreum Min Cheol Joo Moon Yiseul Yu Myong Yong Choi 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期65-80,共16页
We investigated the role of metal atomization and solvent decomposition into reductive species and carbon clusters in the phase formation of transition-metal carbides(TMCs;namely,Co_(3)C,Fe_(3)C,TiC,and MoC)by pulsed ... We investigated the role of metal atomization and solvent decomposition into reductive species and carbon clusters in the phase formation of transition-metal carbides(TMCs;namely,Co_(3)C,Fe_(3)C,TiC,and MoC)by pulsed laser ablation of Co,Fe,Ti,and Mo metals in acetone.The interaction between carbon s-p-orbitals and metal d-orbitals causes a redistribution of valence structure through charge transfer,leading to the formation of surface defects as observed by X-ray photoelectron spectroscopy.These defects influence the evolved TMCs,making them effective for hydrogen and oxygen evolution reactions(HER and OER)in an alkaline medium.Co_(3)C with more oxygen affinity promoted CoO(OH)intermediates,and the electrochemical surface oxidation to Co_(3)O_(4)was captured via in situ/operando electrochemical Raman probes,increasing the number of active sites for OER activity.MoC with more d-vacancies exhibits strong hydrogen binding,promoting HER kinetics,whereas Fe_(3)C and TiC with more defect states to trap charge carriers may hinder both OER and HER activities.The results show that the assembled membrane-less electrolyzer with Co_(3)C∥Co_(3)C and MoC∥MoC electrodes requires~2.01 and 1.99 V,respectively,to deliver a 10 mA cm−2 with excellent electrochemical and structural stability.In addition,the ascertained pulsed laser synthesis mechanism and unit-cell packing relations will open up sustainable pathways for obtaining highly stable electrocatalysts for electrolyzers. 展开更多
关键词 ACETONE H_(2)and O_(2)evolution reactions pulsed laser ablation surface defects transition-metal carbides water electrolyzer
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Anode surface engineering of zinc-ion batteries using tellurium nanobelt as a protective layer for enhancing energy storage performance
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作者 Soobeom Lee Yeonjin Je +7 位作者 Boeun Seok Hyun Tae Kim Yong-Ryun Jo Soong Ju Oh Byoungyong Im Dae Guen Kim Sang-Soo Chee Geon-Hyoung An 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期113-123,共11页
Over the years,zinc-ion batteries(ZIBs)have attracted attention as a promising next-generation energy storage technology because of their excellent safety,long cycling performance,eco-friendliness,and high-power densi... Over the years,zinc-ion batteries(ZIBs)have attracted attention as a promising next-generation energy storage technology because of their excellent safety,long cycling performance,eco-friendliness,and high-power density.However,issues,such as the corrosion and dissolution of the Zn anode,limited wet-tability,and lack of sufficient nucleation sites for Zn plating,have limited their practical application.The introduction of a protective layer comprising of tellurium(Te)nanobelts onto the surface of Zn anode has emerged as a promising approach to overcome these limitations and improve the electrochemical behav-ior by enhancing the safety and wettability of ZIBs,as well as providing numerous nucleation sites for Zn plating.In the presence of a Te-based protective layer,the energy power density of the surface-engineered Zn anode improved significantly(ranging from 310 to 144 W h kg^(-1),over a power density range of 270 to 1,800 W kg^(-1)),and the lifespan capability was extended.These results demonstrate that the proposed strategy of employing Te nanobelts as a protective layer holds great promise for enhancing the energy storage performance of zIBs,making them even more attractive as a viable energy storage solution forthefuture. 展开更多
关键词 Zn ion battery ANODE Protective layer TELLURIUM NANOBELT
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Disordered Structure and Reversible Phase Transformation from K-Birnessite to Zn-Buserite Enable High-Performance Aqueous Zinc-lon Batteries
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作者 Nibagani Naresh Suyoon Eom +4 位作者 Sang Jun Lee Su Hwan Jeong Ji-Won Jung Young Hwa Jung Joo-Hyung Kim 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期100-111,共12页
The layeredδ-MnO_(2)(dMO)is an excellent cathode material for rechargeable aqueous zinc-ion batteries owing to its large interlayer distance(~0.7 nm),high capacity,and low cost;however,such cathodes suffer from struc... The layeredδ-MnO_(2)(dMO)is an excellent cathode material for rechargeable aqueous zinc-ion batteries owing to its large interlayer distance(~0.7 nm),high capacity,and low cost;however,such cathodes suffer from structural degradation during the long-term cycling process,leading to capacity fading.In this study,a Co-doped dMO composite with reduced graphene oxide(GC-dMO)is developed using a simple cost-effective hydrothermal method.The degree of disorderness increases owing to the hetero-atom doping and graphene oxide composites.It is demonstrated that layered dMO and GC-dMO undergo a structural transition from K-birnessite to the Zn-buserite phase upon the first discharge,which enhances the intercalation of Zn^(2+)ions,H_(2)O molecules in the layered structure.The GC-dMO cathode exhibits an excellent capacity of 302 mAh g^(-1)at a current density of 100 mAg^(-1)after 100 cycles as compared with the dMO cathode(159 mAhg^(-1)).The excellent electrochemical performance of the GC-dMO cathode owing to Co-doping and graphene oxide sheets enhances the interlayer gap and disorderness,and maintains structural stability,which facilitates the easy reverse intercalation and de-intercalation of Zn^(2+)ions and H_(2)O molecules.Therefore,GC-dMO is a promising cathode material for large-scale aqueous ZIBs. 展开更多
关键词 aqueous zinc-ion batteries BIRNESSITE buserite disordered structure phase transformation
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Methane Emission from Rice Fields:Necessity for Molecular Approach for Mitigation
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作者 Sujeevan RAJENDRAN Hyeonseo PARK +6 位作者 Jiyoung KIM Soon Ju PARK Dongjin SHIN Jong-Hee LEE Young Hun SONG Nam-Chon PAEK Chul Min KIM 《Rice science》 SCIE CSCD 2024年第2期159-178,共20页
Anthropogenic methane emissions are a leading cause of the increase in global averagetemperatures,often referred to as global warming.Flooded soils play a significant role in methaneproduction,where the anaerobic cond... Anthropogenic methane emissions are a leading cause of the increase in global averagetemperatures,often referred to as global warming.Flooded soils play a significant role in methaneproduction,where the anaerobic conditions promote the production of methane by methanogenicmicroorganisms.Rice fields contribute a considerable portion of agricultural methane emissions,as riceplants provide both factors that enhance and limit methane production.Rice plants harbor both methaneproducingand methane-oxidizing microorganisms.Exudates from rice roots provide source for methaneproduction,while oxygen delivered from the root aerenchyma enhances methane oxidation.Studies haveshown that the diversity of these microorganisms depends on rice cultivars with some genes characterizedas harboring specific groups of microorganisms related to methane emissions.However,there is still aneed for research to determine the balance between methane production and oxidation,as rice plantspossess the ability to regulate net methane production.Various agronomical practices,such as fertilizerand water management,have been employed to mitigate methane emissions.Nevertheless,studiescorrelating agronomic and chemical management of methane with productivity are limited.Moreover,evidences for breeding low-methane-emitting rice varieties are scattered largely due to the absence ofcoordinated breeding programs.Research has indicated that phenotypic characteristics,such as rootbiomass,shoot architecture,and aerenchyma,are highly correlated with methane emissions.This reviewdiscusses available studies that involve the correlation between plant characteristics and methaneemissions.It emphasizes the necessity and importance of breeding low-methane-emitting rice varieties inaddition to existing agronomic,biological,and chemical practices.The review also delves into the idealphenotypic and physiological characteristics of low-methane-emitting rice and potential breeding techniques,drawing from studies conducted with diverse varieties,mutants,and transgenic plants. 展开更多
关键词 methane emission rice breeding AERENCHYMA greenhouse gas radial oxygen loss
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Changes in structural plasticity of hippocampal neurons in an animal model of multiple sclerosis
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作者 Poornima D.E.Weerasinghe-Mudiyanselage Sohi Kang +4 位作者 Joong-Sun Kim Sung-Ho Kim Hongbing Wang Taekyun Shin Changjong Moon 《Zoological Research》 SCIE CSCD 2024年第2期398-414,共17页
Structural plasticity is critical for the functional diversity of neurons in the brain.Experimental autoimmune encephalomyelitis(EAE)is the most commonly used model for multiple sclerosis(MS),successfully mimicking it... Structural plasticity is critical for the functional diversity of neurons in the brain.Experimental autoimmune encephalomyelitis(EAE)is the most commonly used model for multiple sclerosis(MS),successfully mimicking its key pathological features(inflammation,demyelination,axonal loss,and gliosis)and clinical symptoms(motor and non-motordysfunctions).Recentstudieshave demonstrated the importance of synaptic plasticity in EAE pathogenesis.In the present study,we investigated the features of behavioral alteration and hippocampal structural plasticity in EAE-affected mice in the early phase(11 days post-immunization,DPI)and chronic phase(28DPI).EAE-affected mice exhibited hippocampus-related behavioral dysfunction in the open field test during both early and chronic phases.Dendritic complexity was largely affected in the cornu ammonis 1(CA1)and CA3 apical and dentate gyrus(DG)subregions of the hippocampus during the chronic phase,while this effect was only noted in the CA1 apical subregion in the early phase.Moreover,dendritic spine density was reduced in the hippocampal CA1 and CA3 apical/basal and DG subregions in the early phase of EAE,but only reduced in the DG subregion during the chronic phase.Furthermore,mRNA levels of proinflammatory cytokines(Il1β,Tnfα,and Ifnγ)and glial cell markers(Gfap and Cd68)were significantly increased,whereas the expression of activity-regulated cytoskeletonassociated protein(ARC)was reduced during the chronic phase.Similarly,exposure to the aforementioned cytokines in primary cultures of hippocampal neurons reduced dendritic complexity and ARC expression.Primary cultures of hippocampal neurons also showed significantly reduced extracellular signal-regulated kinase(ERK)phosphorylation upon treatment with proinflammatory cytokines.Collectively,these results suggest that autoimmune neuroinflammation alters structural plasticity in the hippocampus,possibly through the ERK-ARC pathway,indicating that this alteration may be associated with hippocampal dysfunctions in EAE. 展开更多
关键词 Activity-regulated cytoskeleton-associated protein Anxiety-like behavior Experimental autoimmune encephalomyelitis Hippocampal dysfunction NEUROINFLAMMATION
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Neuralgic amyotrophy with hourglass-like constrictions:A case report
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作者 Mi-Hyeon Bang Ha-Lim Song +2 位作者 Seok Hahn Wanil Kim Hwan-Kwon Do 《World Journal of Clinical Cases》 SCIE 2024年第34期6728-6735,共8页
BACKGROUND Neuralgic amyotrophy(NA)is a rare disease with sudden upper limb pain followed by affected muscle weakness.The most commonly affected area in NA is the upper part of the brachial plexus,and the paraspinal m... BACKGROUND Neuralgic amyotrophy(NA)is a rare disease with sudden upper limb pain followed by affected muscle weakness.The most commonly affected area in NA is the upper part of the brachial plexus,and the paraspinal muscles are rarely affected(1.5%),making these cases difficult to distinguish from cervical radiculopathy.CASE SUMMARY A 76-year-old male presented to the emergency department with left hip pain post-fall.After undergoing left femoral neck fracture surgery,he experienced sudden left shoulder pain for 10 days with subsequent left arm weakness.Cervical spine computed tomography revealed mild right asymmetric intervertebral disc bulging with a decreased C5-6disc space.Three weeks later,an electrodiagnostic study confirmed brachial plexopathy findings involving the cervical root.Magnetic resonance neurography was performed for a differential diagnosis.Contrast enhancement was identified at the upper trunk of the brachial plexus,including the C5 nerve root.A suprascapular nerve hourglass-like focal constriction(HLFC)was also identified,confirming NA.After being diagnosed with NA,the patient received 15 mg prednisolone,twice daily,for 3 weeks.Physical therapy was initiated,including left arm strengthening exercises and electrical stimulation therapy.Left shoulder muscle strength significantly improved one CONCLUSION NA's unique features like HLFC and paraspinal involvement are crucial for accurate diagnosis,avoiding confusion with cervical radiculopathy. 展开更多
关键词 Neuralgic amyotrophy Cervical radiculopathy Hourglass-like focal constriction Paraspinal muscle Magnetic resonance neurography Case report
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Factors Influencing Compliance with Safe Handling Requirements of Anticancer Agents by Nurses in a Tertiary Hospital-A Secondary Publication
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作者 Seul Gi Lee So-Young Choi 《Journal of Clinical and Nursing Research》 2024年第1期196-208,共13页
Purpose:This research aimed to identify leading factors that affect nurses’compliance with the safe handling of anticancer agents.Methods:Data were collected from 114 nurses working in the university hospital and wer... Purpose:This research aimed to identify leading factors that affect nurses’compliance with the safe handling of anticancer agents.Methods:Data were collected from 114 nurses working in the university hospital and were analyzed through independent t-test,one-way ANOVA,Pearson’s correlation coefficient,and multiple regression analysis using SPSS25.0.Results:The average level of compliance with the safe handling of anticancer agents was 3.73±0.33 out of 5 points.Workplace safety culture(β=0.40,P<0.001)and knowledge of safe handling(β=0.18,P=0.030)had significant influences on nurses’compliance with the safe handling of anticancer agents.The explained variance for compliance was 28.3%.Conclusion:To enhance the implementation of safety management for anticancer agents,each institution should strive to support human and material resources and enhance specialization in the workplace safety culture through system improvement.Based on the results of this study,we suggest research for the development of a training program for anticancer agent safety management. 展开更多
关键词 Anticancer agents COMPLIANCE Knowledge NURSE Safety
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关于BL-代数的模糊滤子与模糊理想(英文) 被引量:27
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作者 张小红 Jun Young Bae Doh Myung Im 《模糊系统与数学》 CSCD 北大核心 2006年第3期8-20,共13页
在BL-代数中引入模糊超滤子和模糊固执滤子的概念,证明了如下条件对于BL-代数的非常数模糊滤子f来说是等价的:(1)f是布尔的和素的,(2)f是蕴涵的和素的,(3)f是超的,(4)f是固执的。应用模糊正蕴涵滤子给出G-代数的若干特征性质。提出BL-... 在BL-代数中引入模糊超滤子和模糊固执滤子的概念,证明了如下条件对于BL-代数的非常数模糊滤子f来说是等价的:(1)f是布尔的和素的,(2)f是蕴涵的和素的,(3)f是超的,(4)f是固执的。应用模糊正蕴涵滤子给出G-代数的若干特征性质。提出BL-代数模糊理想的概念,给出一些重要例子,并通过例子说明在BL-代数中模糊理想一般不能由模糊滤子导出。同时,从模糊理想出发构造了商BL-代数,并建立了相应的同态基本定理。最后,研究了BL-代数的几类模糊理想及其相互关系,给出模糊布尔理想、模糊素理想、模糊超理想的特征性质。 展开更多
关键词 BL-代数 模糊超滤子 模糊固执滤子 G-代数 模糊理想 商BL-代数
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Synthesis of nanostructured Li_2FeSiO_4/C cathode for lithium-ion battery by solution method 被引量:1
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作者 杨蓉 刘晓艳 +2 位作者 曲冶 雷京 Jou-Hyeon AHN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第10期2529-2534,共6页
Nanosphere-like Li2FeSiO4/C was synthesized via a solution method using sucrose as carbon sources under a mild condition of time-saving and energy-saving, followed by sintering at high temperatures for crystallization... Nanosphere-like Li2FeSiO4/C was synthesized via a solution method using sucrose as carbon sources under a mild condition of time-saving and energy-saving, followed by sintering at high temperatures for crystallization. The amount of carbon in the composite is less than 10% (mass fraction), and the X-ray diffraction result confirms that the sample is of pure single phase indexed with the orthorhombic Pmn21 space group. The particle size of the Li2FeSiO4/C synthesized at 700 °C for 9 h is very fine and spherical-like with a size of 200 nm. The electrochemical performance of this material, including reversible capacity, cycle number, and charge-discharge characteristics, were tested. The cell of this sample can deliver a discharge capacity of 166 mA-h/g at C/20 rate in the first three cycles. After 30 cycles, the capacity decreases to 158 mA-h/g, and the capacity retention is up to 95%. The results show that this method can prepare nanosphere-like Li2FeSiO4/C composite with good electrochemical performance. 展开更多
关键词 lithium-ion batteries cathode material Li2FeSiO4/C solution method
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碳纳米管/氯化镁负载钛基Ziegler-Natta催化剂在异戊二烯聚合中的应用(英文) 被引量:1
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作者 曹兰 蒲诚勇 宗成中 《合成橡胶工业》 CAS 北大核心 2019年第3期233-233,共1页
以大内径碳纳米管、羟基化碳纳米管及氯化镁作载体,采用高能球磨技术制备了纳米级钛系ZieglerNatta催化剂,研究了该催化剂对反式聚异戊二烯聚合过程的影响。结果表明,反式聚异戊二烯/碳纳米管复合材料具有管状结构,碳纳米管颗粒分散良好... 以大内径碳纳米管、羟基化碳纳米管及氯化镁作载体,采用高能球磨技术制备了纳米级钛系ZieglerNatta催化剂,研究了该催化剂对反式聚异戊二烯聚合过程的影响。结果表明,反式聚异戊二烯/碳纳米管复合材料具有管状结构,碳纳米管颗粒分散良好,并且明显提高了反式聚异戊二烯的热稳定性。 展开更多
关键词 ZIEGLER-NATTA催化剂 反式聚异戊二烯 碳纳米管 热稳定性
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R_0-代数与BL-代数中的素滤子定理(英文) 被引量:3
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作者 张小红 田英培 《工程数学学报》 CSCD 北大核心 2005年第5期935-938,共4页
R0-代数与BL-代数在模糊逻辑的研究中有重要作用,这与布尔代数在经典逻辑中的作用类似。本文通过一个特殊集x?1F分别给出R0?代数及BL-代数素滤子的一个等价条件,并给出BL-代数的一个新性质。应用这些结果分别得到R0-代数与BL-代数的素... R0-代数与BL-代数在模糊逻辑的研究中有重要作用,这与布尔代数在经典逻辑中的作用类似。本文通过一个特殊集x?1F分别给出R0?代数及BL-代数素滤子的一个等价条件,并给出BL-代数的一个新性质。应用这些结果分别得到R0-代数与BL-代数的素滤子定理。 展开更多
关键词 模糊逻辑 R0-代数 BL-代数 MP滤子 素滤子
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共价键合二氧化硅/氧化石墨烯对天然橡胶的多尺度和界面增强及在环保高性能轮胎胎面中的应用(英文)
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作者 曹兰 王庆富 +4 位作者 翟晓康 辛欣 王海瑞 张萌萌 宗成中 《合成橡胶工业》 CAS CSCD 北大核心 2018年第6期475-475,共1页
将零维(0 D) Si 69改性的二氧化硅纳米颗粒(MS)和KH 550官能化的二维(2 D)多层氧化石墨烯(KGO)组成的纳米复合物通过胶乳法制备了天然橡胶(NR)纳米材料,研究了纳米材料的多尺度增强和界面强化。结果表明,通过MS和KGO表面活性极性官能团... 将零维(0 D) Si 69改性的二氧化硅纳米颗粒(MS)和KH 550官能化的二维(2 D)多层氧化石墨烯(KGO)组成的纳米复合物通过胶乳法制备了天然橡胶(NR)纳米材料,研究了纳米材料的多尺度增强和界面强化。结果表明,通过MS和KGO表面活性极性官能团之间良好的H键相互作用形成了0 D/2 D杂化复合物(即MSKGO),后者与异戊二烯单元通过Si 69的硫化物相互作用和非极性相互作用与氧化石墨烯(GO)形成NRMSKGO的三维网络结构;在干燥和固化过程中,H键网络结构转化为共价键网络结构,同时GO部分转变为还原氧化石墨烯(RGO)。含有质量分数为3%GO的复合材料的200%定伸应力和拉伸强度分别提高9. 47倍和1. 36倍;仅使用10份含质量分数1%GO的复合材料替代10份NR制备的轮胎胎面,不仅使炭黑降低5份,且耐磨性和抗湿滑性分别提高了44. 5%和14. 6%,滚动阻力下降了5. 1% 展开更多
关键词 天然胶乳 氧化石墨烯二氧化硅 轮胎胎面 硅烷偶联剂
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心理学在中国发展过程中的通俗化体现
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作者 晋争 《江苏教育学院学报(社会科学版)》 2011年第6期28-30,共3页
心理学在中国的普及程度,无疑是影响心理学科研水平的重要因素之一。心理学在普及化的过程中正在走向通俗化。主要表现在以下几个方面:对心理学基本功能的错误理解,对心理学学习者的偏见,对可从事的与心理学相关职业的认识片面,对心理... 心理学在中国的普及程度,无疑是影响心理学科研水平的重要因素之一。心理学在普及化的过程中正在走向通俗化。主要表现在以下几个方面:对心理学基本功能的错误理解,对心理学学习者的偏见,对可从事的与心理学相关职业的认识片面,对心理学研究领域的认识模糊。应警惕心理学的发展走向通俗化,为未来中国心理学之发展提供参考。 展开更多
关键词 心理学 通俗化 心理学发展
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内隐联系测验的修正——简式内隐联系测验 被引量:14
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作者 晋争 《心理科学进展》 CSSCI CSCD 北大核心 2010年第10期1554-1558,共5页
简式内隐联系测验(Brief Implicit Association Test,BIAT),是对内隐联系测验(Implicit Association Test,IAT)(也称为内隐联想测验)的修正,它由两部分联合任务组成,使用传统IAT中的两类别的属性材料和两类别的概念材料以及与IAT相同的... 简式内隐联系测验(Brief Implicit Association Test,BIAT),是对内隐联系测验(Implicit Association Test,IAT)(也称为内隐联想测验)的修正,它由两部分联合任务组成,使用传统IAT中的两类别的属性材料和两类别的概念材料以及与IAT相同的联接-反应对。在设计BIAT时,焦点类别的选定对其测量效果有着至关重要的影响,Sriram和Greenwald的研究已经初步证明BIAT方法可以成功运用于测量内隐态度,认同和刻板印象。本文回顾了内隐联系测验发展过程中的各种变式,着重介绍了简式内隐联系测验,结合Sriram的应用对其进行综合评价并建议在今后的研究中对此方法进行验证。 展开更多
关键词 简式内隐联系测验(BIAT) 内隐联想测验(IAT) 焦点类别
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Wave dynamic processes in cellular detonation reflection from wedges 被引量:11
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作者 Zongmin Hu Zonglin Jiang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第1期33-41,共9页
When the cell width of the incident detonation wave (IDW) is comparable to or larger than the Mach stem height, self-similarity will fail during IDW reflection from a wedge surface. In this paper, the detonation ref... When the cell width of the incident detonation wave (IDW) is comparable to or larger than the Mach stem height, self-similarity will fail during IDW reflection from a wedge surface. In this paper, the detonation reflection from wedges is investigated for the wave dynamic processes occurring in the wave front, including transverse shock motion and detonation cell variations behind the Mach stem. A detailed reaction model is implemented to simulate two-dimensional cellular detonations in stoichiometric mixtures of H2/O2 diluted by Argon. The numerical results show that the transverse waves, which cross the triple point trajectory of Mach reflection, travel along the Mach stem and reflect back from the wedge surface, control the size of the cells in the region swept by the Mach stem. It is the energy carried by these transverse waves that sustains the triple-wave-collision with a higher frequency within the over-driven Mach stem. In some cases, local wave dynamic processes and wave structures play a dominant role in determining the pattern of cellular record, leading to the fact that the cellular patterns after the Mach stem exhibit some peculiar modes. 展开更多
关键词 Cellular detonation WEDGE Reflection Wave dynamics SIMULATION
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An experimental study on thermal characteristics of nanofluid with graphene and multi-wall carbon nanotubes 被引量:7
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作者 A.K.M Mahmudul Haque Sunghyun Kwon +4 位作者 Junhyo Kim Jungpil Noh Sunchul Huh Hanshik Chung Hyomin Jeong 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期3202-3210,共9页
High-thermal conductivity enhancement of nanofluid is one of the promising topics of the nanoscience research field. This work reports the experimental study on the preparation of graphene(GN) and multi-walled carbon ... High-thermal conductivity enhancement of nanofluid is one of the promising topics of the nanoscience research field. This work reports the experimental study on the preparation of graphene(GN) and multi-walled carbon nanotubes(MWCNTs) based nanofluids with the assistance of sodium dodecyl benzene sulfonate(SDBS) and sodium dodecyl sulfate(SDS) surfactants, and their thermal behaviors. The present work suggests not a solution, but a solution approach and deduces a new conclusion by trying to resolve the agglomeration problem and improve the dispersibility of nanoparticles in the base fluid. The analysis results of FESEM, thermal conductivity, diffusivity, effusivity and heat transfer coefficient enhancement ratio of nanofluid with surfactants SDS and SDBS expose strong evidence of the dispersing effect of surfactant on the making of nanofluid. 展开更多
关键词 GRAPHENE carbon nanotube SURFACTANT DISPERSIBILITY thermal conductivity
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Risk factors of organ failure in cholangitis with bacteriobilia 被引量:8
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作者 Jae Min Lee Sang Hyub Lee +6 位作者 Kwang Hyun Chung Jin Myung Park Ban Seok Lee Woo Hyun Paik Joo Kyung Park Ji Kon Ryu Yong-Tae Kim 《World Journal of Gastroenterology》 SCIE CAS 2015年第24期7506-7513,共8页
AIM: To identify the risk factors for organ failure(OF) in cholangitis with bacteriobilia.METHODS: This study included 182 patients with acute cholangitis who underwent percutaneous transhepatic biliary drainage betwe... AIM: To identify the risk factors for organ failure(OF) in cholangitis with bacteriobilia.METHODS: This study included 182 patients with acute cholangitis who underwent percutaneous transhepatic biliary drainage between January 2005 and April 2013. We conducted a retrospective analysis of comprehensive clinical and laboratory data.RESULTS: There were 24 cases(13.2%) of OF and five deaths(2.7%). Bile culture was positive for microbial growth in 130 out of 138(94.2%) patients. In multivariate analysis of 130 patients with positivebile cultures, significant predictive factors for OF were the presence of extended-spectrum beta-lactamase(ESBL) organisms in blood cultures, pre-existing renal dysfunction, and choledocholithiasis as an etiology, with odds ratios of 15.376, 6.319, and 3.573, respectively. We developed a scoring system with a regression coefficient of each significant variable. The OF score was calculated using the following equation:(2.7 × ESBL organisms in blood cultures) +(1.8 × pre-existing renal dysfunction) +(1.3 × choledocholithiasis). This scoring system for predicting OF was highly specific(99.1%) and had a positive predictive value of 86.2%.CONCLUSION: ESBL organisms in blood cultures, preexisting renal dysfunction, and choledocholithiasis are risk factors for OF in cholangitis with bacteriobilia. The OF scoring system may aid clinicians to identify a poor prognosis group. 展开更多
关键词 ACUTE CHOLANGITIS Bacteriobilia BILE CULTURE ORGAN failure
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