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Estimating the Yield Loss of Winter Wheat from Drought in the United States Southern Plains Region as Influenced by El Niño-Southern Oscillation (ENSO)
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作者 Prem Woli Gerald R. Smith +1 位作者 Charles R. Long Francis M. Rouquette, Jr. 《Agricultural Sciences》 2024年第9期1018-1034,共17页
Wheat (Triticum aestivum L.) production is a major economic activity in most regional and rural areas in the Southern Plains, a semi-arid region of the United States. This region is vulnerable to drought and is projec... Wheat (Triticum aestivum L.) production is a major economic activity in most regional and rural areas in the Southern Plains, a semi-arid region of the United States. This region is vulnerable to drought and is projected to experience a drier climate in the future. Since the interannual variability in climate in this region is linked to an ocean-atmospheric phenomenon, called El Niño-Southern Oscillation (ENSO), droughts in this region may be associated with ENSO. Droughts that occur during the critical growth phases of wheat can be extremely costly. However, the losses due to an impending drought can be minimized through mitigation measures if it is predicted in advance. Predicting the yield loss from an imminent drought is crucial for stakeholders. One of the reliable ways for such prediction is using a plant physiology-based agricultural drought index, such as Agricultural Reference Index for Drought (ARID). This study developed ENSO phase-specific, ARID-based models for predicting the drought-induced yield loss for winter wheat in this region by accounting for its phenological phase-specific sensitivity to drought. The reasonable values of the drought sensitivity coefficients of the yield model for each ENSO phase (El Niño, La Niña, or Neutral) indicated that the yield models reflected reasonably well the phenomena of water stress decreasing the winter wheat yields in this region during different ENSO phases. The values of various goodness-of-fit measures used, including the Nash-Sutcliffe Index (0.54 to 0.67), the Willmott Index (0.82 to 0.89), and the percentage error (20 to 26), indicated that the yield models performed fairly well at predicting the ENSO phase-specific loss of wheat yields from drought. This yield model may be useful for predicting yield loss from drought and scheduling irrigation allocation based on the phenological phase-specific sensitivity to drought as impacted by ENSO. 展开更多
关键词 ARID DRoUGHT Drought Index ENSo El Niño Growth-Stage Model Phenological-Phase Prediction Semi-Arid Wheat Yield Loss
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Novel nervous and multi-system regenerative therapeutic strategies for diabetes mellitus with mTOR 被引量:13
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作者 Kenneth Maiese 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第3期372-385,共14页
Throughout the globe,diabetes mellitus(DM) is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and af... Throughout the globe,diabetes mellitus(DM) is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and affects all components of the central and peripheral nervous systems that can range from dementia to diabetic neuropathy.The mechanistic target of rapamycin(m TOR) is a promising agent for the development of novel regenerative strategies for the treatment of DM.m TOR and its related signaling pathways impact multiple metabolic parameters that include cellular metabolic homeostasis,insulin resistance,insulin secretion,stem cell proliferation and differentiation,pancreatic β-cell function,and programmed cell death with apoptosis and autophagy.m TOR is central element for the protein complexes m TOR Complex 1(m TORC1) and m TOR Complex 2(m TORC2) and is a critical component for a number of signaling pathways that involve phosphoinositide 3-kinase(PI 3-K),protein kinase B(Akt),AMP activated protein kinase(AMPK),silent mating type information regulation 2 homolog 1(Saccharomyces cerevisiae)(SIRT1),Wnt1 inducible signaling pathway protein 1(WISP1),and growth factors.As a result,m TOR represents an exciting target to offer new clinical avenues for the treatment of DM and the complications of this disease.Future studies directed to elucidate the delicate balance m TOR holds over cellular metabolism and the impact of its broad signaling pathways should foster the translation of these targets into effective clinical regimens for DM. 展开更多
关键词 Akt AMP activated protein kinase(AMPK) apoptosis Alzheimer’s disease autophagy β-cell cancer cardiovascular disease caspase CCN family diabetes mellitus epidermal growth factor erythropoietin fibroblast growth factor forkhead transcription factors Fox o FRAP1 hamartin(tuberous sclerosis 1)/tuberin(tuberous sclerosis 2)(TSC1/TSC2) insulin mechanistic target of rapamycin(mToR) m ToR Complex 1(m T oRC1) m ToR Complex 2(m ToRC2) nicotinamide nicotinamide adenine dinucleotide(NAD+) non-communicable diseases oxidative stress phosphoinositide 3-kinase(PI 3-K) programmed cell death silent mating type information regulation 2 homolog 1(Saccharomyces cerevisiae)(SIRT1) sirtuin stem cells wingless Wnt Wnt1 inducible signaling pathway protein 1(WISP1)
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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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Interhemispheric and longitudinal differences in the ionosphere-thermosphere coupling process during the May 2024 superstorm
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作者 WenBo Li LiBo Liu +5 位作者 YuYan Yang TingWei Han RongJin Du RuiLong Zhang HuiJun Le YiDing Chen 《Earth and Planetary Physics》 EI CAS CSCD 2024年第6期910-919,共10页
Geomagnetic storm events have a strong influence on the ionosphere–thermosphere(I-T)coupling system.Analyzing the regional response process of the I-T system and its differences across the northern and southern hemis... Geomagnetic storm events have a strong influence on the ionosphere–thermosphere(I-T)coupling system.Analyzing the regional response process of the I-T system and its differences across the northern and southern hemispheres is an important but challenging task.In this study,we used a combination of multiple observations and a model simulation to examine the north–south hemispheric difference in the I-T coupling system in the American and Asian sectors during the geomagnetic superstorm that occurred in May 2024.Observations of the total electron content(TEC)showed that the Asian sector had negative storms in the northern hemisphere and positive storms in the southern hemisphere,a process that exacerbated the hemispheric differences in the TEC.However,both hemispheres of the American sector showed negative storms.The thermospheric composition changes also differed between the two sectors,and their variation could partially explain the hemispheric differences caused by positive and negative storms.Moreover,the influence of the thermospheric density change was less than that of the thermospheric composition.Finally,the dynamic effect of the thermospheric wind and the plasma transport processes strongly modulated the north–south differences in the TEC at nighttime in the American and Asian sectors,respectively,during this superstorm. 展开更多
关键词 geomagnetic superstorm north–south hemispheric difference total electron content o/N2 thermospheric wind plasma transport
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Autocrine IL-8 Contributes to Propionibacterium Acnes-induced Proliferation and Differentiation of HaCaT Cells via AKT/FOXO1/Autophagy
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作者 Xiu-qin YU Jin-zhu MAO +5 位作者 Shu-yun YANG Lu WANG Chang-zhi YANG Lei HUANG Qi-hong QIAN Ting-ting ZHU 《Current Medical Science》 SCIE CAS 2024年第5期1058-1065,共8页
Objective Proprionibacterium acnes(P.acnes)-induced inflammatory responses,proliferation and differentiation of keratinocytes contribute to the progression of acne vulgaris(AV).P.acnes was found to enhance the product... Objective Proprionibacterium acnes(P.acnes)-induced inflammatory responses,proliferation and differentiation of keratinocytes contribute to the progression of acne vulgaris(AV).P.acnes was found to enhance the production of interleukin-8(IL-8)by keratinocytes.This study aimed to investigate the role of IL-8 in P.acnes-induced proliferation and differentiation of keratinocytes and the underlying mechanism.Methods The P.acnes-stimulated HaCaT cell(a human keratinocyte cell line)model was established.Western blotting and immunofluorescence were performed to detect the expression of the IL-8 receptors C-X-C motif chemokine receptor 1(CXCR1)and C-X-C motif chemokine receptor 2(CXCR2)on HaCaT cells.Cell counting kit-8(CCK-8)assay,5-ethynyl-20-deoxyuridine(EdU)assay and Western blotting were performed to examine the effects of IL-8/CXCR2 axis on the proliferation and differentiation of HaCaT cells treated with P.acnes,the IL-8 neutralizing antibody,the CXCR2 antagonist(SB225002),or the CXCR1/CXCR2 antagonist(G31P).Western blotting,nuclear and cytoplasmic separation,CCK-8 assay,and EdU assay were employed to determine the downstream pathway of CXCR2 after P.acnes-stimulated HaCaT cells were treated with the CXCR2 antagonist,the protein kinase B(AKT)antagonist(AZD5363),or the constitutively active forkhead box O1(FOXO1)mutant.Finally,autophagy markers were measured in HaCaT cells following the transfection of the FOXO1 mutant or treatment with the autophagy inhibitor 3-methyladenine(3-MA).Results The expression levels of CXCR1 and CXCR2 were significantly increased on the membrane of HaCaT cells following P.acnes stimulation.The IL-8/CXCR2 axis predominantly promoted the proliferation and differentiation of P.acnes-induced HaCaT cells by activating AKT/FOXO1/autophagy signaling.In brief,IL-8 bound to its receptor CXCR2 on the membrane of keratinocytes to activate the AKT/FOXO1 axis.Subsequently,phosphorylated FOXO1 facilitated autophagy to promote the proliferation and differentiation of P.acnes-induced keratinocytes.Conclusion This study demonstrated the novel autocrine effect of IL-8 on the proliferation and differentiation of P.acnes-induced keratinocytes,suggesting a potential therapeutic target for AV. 展开更多
关键词 acne vulgaris Proprionibacterium acnes KERATINoCYTE INTERLEUKIN-8 C-X-C motif chemokine receptor 2 protein kinase B forkhead box o1 AUToPHAGY
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Circulation Pattern Controls of Summer Temperature Anomalies in Southern Africa
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作者 Chibuike Chiedozie IBEBUCHI Cameron C.LEE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期341-354,共14页
This study investigates the relationship between circulation patterns and austral summer temperature anomalies in southern Africa. The results show that the formation of continental lows tends to increase the thicknes... This study investigates the relationship between circulation patterns and austral summer temperature anomalies in southern Africa. The results show that the formation of continental lows tends to increase the thickness of the lower atmosphere. Further, the distinct variabilities of high and low pressure under the circulation types, influence air mass advection from the adjacent oceans, as well as atmospheric stability over land. Stronger anticyclonic circulation at the western branch of the Mascarene high-pressure system enhances the low-level cold air advection by southeast winds,decreases the thickness, and lowers the temperature over a majority of the land in southern Africa. Conversely, a weaker Mascarene High, coupled with enhanced cyclonic activity in the southwest Indian Ocean increases low-level warm air advection and increases temperature anomalies over vast regions in southern Africa. The ridging of a closed South Atlantic anticyclone at the southern coast of southern Africa results in colder temperatures near the tip of southern Africa due to enhanced low-level cold air advection by southeast winds. However, when the ridge is weak and westerly winds dominate the southern coast of southern Africa, these areas experience temperature increases. The northward track of the Southern Hemisphere mid-latitude cyclone, which can be linked to the negative Southern Annular Mode, reduces the temperature in the southwestern part of southern Africa. Also, during the analysis period, El Ni?o was associated with temperature increases over the central parts of southern Africa;while the positive Indian Ocean dipole was linked to a temperature increase over the northeastern, northwestern, and southwestern parts of southern Africa. 展开更多
关键词 TEMPERATURE circulation types Subtropical Indian ocean dipole Southern Annular Mode El Ni?o Indian ocean dipole Mascarene High South Atlantic anticyclone
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Na_(2)O对锂铝硅微晶玻璃析晶及性能的影响
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作者 郑伟宏 王启东 +3 位作者 高子鹏 张浩 袁坚 田培静 《硅酸盐通报》 CAS 北大核心 2024年第4期1301-1307,共7页
采用熔融法制备了不同Na_(2)O含量的透明锂铝硅微晶玻璃,通过DSC、XRD、FESEM等测试方法研究了不同Na_(2)O含量对玻璃析晶及性能的影响。结果表明:Na_(2)O的引入能显著降低玻璃的转变温度和析晶温度,抑制LiAlSi_(4)O_(10)晶相的析出。但... 采用熔融法制备了不同Na_(2)O含量的透明锂铝硅微晶玻璃,通过DSC、XRD、FESEM等测试方法研究了不同Na_(2)O含量对玻璃析晶及性能的影响。结果表明:Na_(2)O的引入能显著降低玻璃的转变温度和析晶温度,抑制LiAlSi_(4)O_(10)晶相的析出。但Na_(2)O的引入促使微晶玻璃中析出Li_(2)Si_(2)O_(5)新相,并且随着Na_(2)O引入量的增加,Li_(2)Si_(2)O_(5)转变为主晶相。由于晶体尺寸均为纳米级,主晶相的转变对透过率影响较小,微晶玻璃的可见光透过率均高于85%。主晶相的转变有效增强了微晶玻璃的机械性能,其弯曲强度由300 MPa提升至331 MPa。Na_(2)O的引入有效增强了Na-K交换,Na_(2)O含量为4%(质量分数)的Li 2O-Al_(2)O_(3)-SiO_(2)微晶玻璃在410℃的KNO_(3)熔盐中交换6 h后,维氏硬度由7.108 GPa提升至7.403 GPa,弯曲强度由331 MPa提升至470 MPa。 展开更多
关键词 Na_(2)o LiAlSi_(4)o_(10) Li_(2)Si_(2)o_(5) Li_(2)o-Al_(2)o_(3)-Sio_(2)微晶玻璃 主晶相转变 Na-K交换
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Petrographic and Geochemical Characteristics of the Pouni Palaeoproterozoic Formations North of the Léo Square Degree (Burkina Faso, West Africa)
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作者 Adama Ouédraogo Yaméogo Pascal Ouiya +4 位作者 Hubert Gounwendmanaghré Zongo Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta Naba 《Open Journal of Geology》 CAS 2024年第1期126-141,共16页
The Pouni area is made up of basalts belonging to the Boromo belt, lamprophyres and granitoids. These geological formations are similar to geological formations of the same type in other regions of the Palaeoproterozo... The Pouni area is made up of basalts belonging to the Boromo belt, lamprophyres and granitoids. These geological formations are similar to geological formations of the same type in other regions of the Palaeoproterozoic domain of the Man/Leo shield. This study, which focused on the petrographic and geochemical characteristics of these geological formations, led to the following main conclusions: The lamprophyres are basic plutonic rocks that cut through other geological formations. The basalt belongs to the northern part of the Borormo belt and is thought to be a relic of overthickened oceanic plateaus. There are two groups of granitoid rocks. The granodiorite has a geochemical signature close to that of Archean TTGs and is metaluminous in character. It has a low potassium content. The minor element and rare earth element spectra indicate that it could be derived from partial melting of basic magmatic rocks. Biotite granites are peraluminous and highly potassic. Minor element contents and rare earth spectra indicate that they could be derived from partial melting of felsic materials. Geotectonic diagrams show that the granitoids identified in the Pouni zone were emplaced in an active tectonic context, similar to that of present-day subduction zones. 展开更多
关键词 Burkina Faso Dori Man/Léo Shield PETRoGRAPHY Geochemistry Partial Melting Geotectonic Context
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Polypyride intercalation boosting the kinetics and stability of V_(3)O_(7)·H_(2)O cathodes for aqueous zinc-ion batteries
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作者 Qingqing He Jie Bai +4 位作者 Mengda Xue Yanxin Liao Huayu Wang Mujun Long Lingyun Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期361-370,I0007,共11页
V_(3)O_(7)·H_(2)O(VO)is a high capacity cathode material in the field of aqueous zinc ion batteries(AZIBs),but it is limited by slow ion migration and low electrical conductivity.In this paper,polypyridine(PPyd)i... V_(3)O_(7)·H_(2)O(VO)is a high capacity cathode material in the field of aqueous zinc ion batteries(AZIBs),but it is limited by slow ion migration and low electrical conductivity.In this paper,polypyridine(PPyd)intercalated VO with nanoribbon structure was prepared by a simple in-situ pre-intercalation,which is noted VO-PPyd.The total density of states(TDOS)shows that after the pre-intercalation of PPyd,an intermediate energy level appears between the valence band and conduction band,which provides a step that can effectively reduce the band gap and enhance the electron conductivity.Furthermore,the density functional theory(DFT)results found that Zn^(2+)is more easily de-intercalated from the V-O skeleton,which proves that the embeddedness of PPyd improves the diffusion kinetics of Zn^(2+).Electrochemical studies have shown that VO-PPyd cathode materials exhibit excellent rate performance(high specific capacity of 465 and 192 mA h g^(-1)at 0.2 and 10 A g^(-1),respectively)and long-term cycling performance(92.7%capacity retention rate after 5300 cycles),due to their advantages in structure and composition.More importantly,the energy density of VO-PPyd//Zn at 581 and 5806 W kg^(-1)is 375 and 247 W h kg^(-1),respectively.VO-PPyd exhibits excellent electrochemical properties compared to previously reported vanadium based cathodes,which makes it highly competitive in the field of high-performance cathode materials of AZIBs. 展开更多
关键词 V_(3)o_(7)·H_(2)o PoLYPYRIDINE Ion migration Electrical conductivity Aqueous zinc ion batteries DFT calculation
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El Niño and the AMO Sparked the Astonishingly Large Margin of Warming in the Global Mean Surface Temperature in 2023 被引量:2
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作者 Kexin LI Fei ZHENG +1 位作者 Jiang ZHU Qing-Cun ZENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1017-1022,共6页
In 2023,the majority of the Earth witnessed its warmest boreal summer and autumn since 1850.Whether 2023 will indeed turn out to be the warmest year on record and what caused the astonishingly large margin of warming ... In 2023,the majority of the Earth witnessed its warmest boreal summer and autumn since 1850.Whether 2023 will indeed turn out to be the warmest year on record and what caused the astonishingly large margin of warming has become one of the hottest topics in the scientific community and is closely connected to the future development of human society.We analyzed the monthly varying global mean surface temperature(GMST)in 2023 and found that the globe,the land,and the oceans in 2023 all exhibit extraordinary warming,which is distinct from any previous year in recorded history.Based on the GMST statistical ensemble prediction model developed at the Institute of Atmospheric Physics,the GMST in 2023 is predicted to be 1.41℃±0.07℃,which will certainly surpass that in 2016 as the warmest year since 1850,and is approaching the 1.5℃ global warming threshold.Compared to 2022,the GMST in 2023 will increase by 0.24℃,with 88%of the increment contributed by the annual variability as mostly affected by El Niño.Moreover,the multidecadal variability related to the Atlantic Multidecadal Oscillation(AMO)in 2023 also provided an important warming background for sparking the GMST rise.As a result,the GMST in 2023 is projected to be 1.15℃±0.07℃,with only a 0.02℃ increment,if the effects of natural variability—including El Niño and the AMO—are eliminated and only the global warming trend is considered. 展开更多
关键词 record-breaking temperature global mean surface temperature El Niño AMo global warming
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Effect of Nanostructures Addition and Enhancement of Poly (Vinylidene Difluoride) (PVDF) Energy Harvesting
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作者 Omar Peña-Oliveras Brenda Javier-Boodhan +1 位作者 Anthony La Santa Juan Gonzalez-Sanchez 《Materials Sciences and Applications》 2024年第7期228-244,共17页
With concerns in energy crisis and global warming, researchers are actively investigating alternative energy renewable solutions. Among the various methods, piezoelectric transduction stands out due to its impressive ... With concerns in energy crisis and global warming, researchers are actively investigating alternative energy renewable solutions. Among the various methods, piezoelectric transduction stands out due to its impressive electromechanical coupling factor and coefficient. As a result, piezoelectric energy harvesting has garnered significant attention from the scientific community. In this study, we explored methods to enhance the piezoelectric properties of polyvinylidene fluoride (PVDF) through two distinct approaches. The first approach involved applying external high voltages at various stages during the mixture reaction. The goal was to determine whether this voltage application could alter or enhance PVDF’s piezoelectric conformation by improving the alignment of polarized dipoles. In the second part of our study, we investigated the effects of incorporating various nanostructures (including Iron Oxide, Magnesium Oxide, and Zinc Oxide) into PVDF. To analyze changes in PVDF’s crystalline structure, we utilized Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD) techniques. Additionally, we measured the electric polarization of samples using a Precision LC Meter and examined the morphology of nanofibers through Scanning Electron Microscopy (SEM). 展开更多
关键词 Poly (Vinylidene Fluoride) (PVDF) Energy Harvesting ELECTRoSPINNING Nanoparticles Zno Mgo FE3o4
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携带nosZⅡ基因的非反硝化菌缓解土壤N_(2)O排放的研究进展
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作者 贾晓雨 张欣 +4 位作者 孙健聪 刘帅 巩晓梦 胡坚挺 夏宗伟 《生物化工》 CAS 2024年第1期167-170,共4页
氧化亚氮是主要的温室气体之一,农田土壤是重要的人为N_(2)O排放源,探索合理的农田N_(2)O减排措施是亟待解决的重大课题。反硝化过程中N_(2)O还原为N_(2)是目前已知的唯一的生物途径的N_(2)O汇,利用能够还原N_(2)O的微生物菌群是减缓农... 氧化亚氮是主要的温室气体之一,农田土壤是重要的人为N_(2)O排放源,探索合理的农田N_(2)O减排措施是亟待解决的重大课题。反硝化过程中N_(2)O还原为N_(2)是目前已知的唯一的生物途径的N_(2)O汇,利用能够还原N_(2)O的微生物菌群是减缓农田土壤N_(2)O排放的潜在途径,对催化N_(2)O还原功能基因nosZ的研究表明N_(2)O还原菌存在两种基因型。本文主要综述了两种类型的N_(2)O还原菌具有不同的系统发育特征、生理学特性,以及N_(2)O还原的酶促动力学,相比较而言,具有nosZⅡ型的N_(2)O还原菌表现出更强的环境适应性,因此是有竞争力的土壤N_(2)O汇的潜在菌群。 展开更多
关键词 土壤N_(2)o排放 农田N_(2)o减排措施 N_(2)o还原菌 nosZⅠ nosZⅡ
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Influence of Reactive Volatile Organic Compounds on Ozone Production in Houston-Galveston-Brazoria Area
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作者 Samarita Sarker Raghava R. Kommalapati Ziaul Huque 《Journal of Environmental Protection》 2015年第4期399-408,共10页
Secondary pollutant ozone (O3) formation in a particular area is often influenced by various factors. Source of emissions is one of the factors. In south east Texas, Houston-Galveston-Brazoria (HGB) is a marginal non-... Secondary pollutant ozone (O3) formation in a particular area is often influenced by various factors. Source of emissions is one of the factors. In south east Texas, Houston-Galveston-Brazoria (HGB) is a marginal non-attainment area for ozone (O3). A summer episode of May 28 to July 2, 2006 is simulated using Comprehensive Air Quality Model with extensions (CAMx). During this period O3 concentration in HGB often exceeds the National Ambient Air Quality Standards (NAAQS) 0.075 ppm of average 8 hour O3 concentration. HGB area has numerous point sources. Various studies found that some specific volatile organic compounds are very reactive in atmosphere. The objective of this study is to analyze the influence of volatile organic compounds present in point source emissions on the air quality of HGB area. For this purpose ozone sensitivity for HGB area is analyzed by the ratio of hydrogen peroxides (H2O2) to nitric acid (HNO3). HGB area is found NOx limited but reactive VOCs are found to be influential too. From (1-4 June, 2006) maximum O3 concentration was found on weekend, June 3. VOCs such as Acetaldehyde (ALD2), Formaldehyde (FORM) and Alkane (ETHA) showed good correlation with O3 concentrations on that day. In addition, Peroxyacetyl nitrate (PAN) formation was found correlated to higher ozone production. Criteria pollutant Sulfur dioxide (SO2) was found to influence the ALD2 and ETHA concentrations, and thus indirectly influenced O3 production. 展开更多
关键词 Comprehensive Air Quality Model with Extensions (CAMx) Nitrogen oxides (Nox) ozone (o3) VoLATILE organic Compound (VoC) Correlation of VoC with o3
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Layer-by-layer fabrication of montmorillonite coating immobilizing Cu_(2)O nanoparticles for continuously catalyzing glycerol to dihydroxyacetone
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作者 Kejin Li Jiahui Liu +2 位作者 Dajian Li Xiaolan Chen Chunhui Zhou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期263-275,共13页
Microreactors are increasingly used for green and safe chemical processes owing to their benefits of superior mass and heat transfer,increased yield,safety,and simplicity of control.However,immobilizing catalysts in m... Microreactors are increasingly used for green and safe chemical processes owing to their benefits of superior mass and heat transfer,increased yield,safety,and simplicity of control.However,immobilizing catalysts in microreactors remains challenging.In this investigation,a technique for creating Cu_(2)O/montmorillonite catalyst coating,using electrostatic attraction for layer-by-layer self-assembly,was proposed.The montmorillonite film's morphology and thickness could be efficiently regulated by adjusting the degree of exfoliation and surface charge of montmorillonite,alongside layer-by-layer coating times.The Cu_(2)O nanoparticles were immobilized using the flow deposition approach.The resulting Cu_(2)O@montmorillonite-film-coated capillary microreactor successfully transformed glycerol into dihydroxyacetone.The conversion of glycerol and product selectivity could be controlled by adjusting the molar ratio of reactants,temperature,residence time,and Cu_(2)O loading.The maximum glycerol conversion observed was 47.6%,with a 27%selectivity toward dihydroxyacetone.The study presents a technique for immobilizing montmorillonite-based catalyst coatings in capillary tubing,which can serve as a foundation for the future application of microreactors in glycerol conversion. 展开更多
关键词 Microreactor CoATING MoNTMoRILLoNITE GLYCERoL Cu_(2)o
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Heteroatom tuning in agarose derived carbon aerogel for enhanced potassium ion multiple energy storage
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作者 Kaijun Xie Xin Liu +5 位作者 Haolin Li Long Fang Kai Xia Dongjiang Yang Yihui Zou Xiaodong Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期239-254,共16页
The incorporation of heteroatoms into carbon aerogels(CAs)can lead to structural distortions and changes in active sites due to their smaller size and electronegativity compared to pure carbon.However,the evolution of... The incorporation of heteroatoms into carbon aerogels(CAs)can lead to structural distortions and changes in active sites due to their smaller size and electronegativity compared to pure carbon.However,the evolution of the electronic structure from single-atom doping to heteroatom codoping in CAs has not yet been thoroughly investigated,and the impact of codoping on potassium ion(K+)storage and diffusion pathways as electrode material remains unclear.In this study,experimental and theoretical simulations were conducted to demonstrate that heteroatom codoping,composed of multiple heteroatoms(O/N/B)with different properties,has the potential to improve the electrical properties and stability of CAs compared to single-atom doping.Electronic states near the Fermi level have revealed that doping with O/N/B generates a greater number of active centers on adjacent carbon atoms than doping with O and O/N atoms.As a result of synergy with enhanced wetting ability(contact angle of 9.26°)derived from amino groups and hierarchical porous structure,ON-CA has the most optimized adsorption capacity(−1.62 eV)and diffusion barrier(0.12 eV)of K^(+).The optimal pathway of K^(+)in ON-CA is along the carbon ring with N or O doping.As K^(+)storage material for supercapacitors and ion batteries,it shows an outstanding specific capacity and capacitance,electrochemical stability,and rate performance.Especially,the assembled symmetrical K^(+)supercapacitor demonstrates an energy density of 51.8 Wh kg^(−1),an ultrahigh power density of 443Wkg^(−1),and outstanding cycling stability(maintaining 83.3%after 10,000 cycles in 1M KPF6 organic electrolyte).This research provides valuable insights into the design of highperformance potassium ion storage materials. 展开更多
关键词 AGARoSE carbon aerogels o/N/B codoping potassium-ion battery potassium-ion supercapacitor
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Solar-driven CO_(2) conversion to methane and methanol using different nanostructured Cu_(2)O-based catalysts modified with Au nanoparticles
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作者 João Angelo Lima Perini Lilian D.Moura Torquato +7 位作者 Juliana Fde Brito Gustavo A.Andolpho Mateus A.Gonçalves Leonardo D.De Angelis Lucas D.Germano Susana I.Córdoba de Torresi Teodorico C.Ramalho Maria V.Boldrin Zanoni 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期287-298,共12页
This work describes the use of TiO_(2)nanotubes-based electrodes(TNT)modified with Cu_(2)O nanostructures and gold nanoparticles for the photoelectroreduction of CO_(2)to produce value-added compounds.A thin layer of ... This work describes the use of TiO_(2)nanotubes-based electrodes(TNT)modified with Cu_(2)O nanostructures and gold nanoparticles for the photoelectroreduction of CO_(2)to produce value-added compounds.A thin layer of polydopamine was used as both an adherent agent and an electron transfer mediator,due to itsπ-conjugated electron system.The highest production yield was achieved using a TNT@PDA/Nc/Au40%electrode,with Faradaic efficiencies of 47.4%(110.5μM cm^(-2))and 27.8%(50.4μM cm^(-2))for methanol and methane,respectively.The performance of the photoelectrodes was shown to be Cu_(2)O facet-dependent,with cubic structures leading to greater conversion of CO_(2)to methanol(43%)and methane(27%),compared to the octahedral morphology,while a higher percentage of metallic gold on the nanostructured Cu_(2)O surface was mainly important for CH4production.Density functional theory(DFT)calculations supported these findings,attributing the superior photoelectrocatalytic performance of the TNT@PDA/Nc/Au40%electrode for CH4generation to the formation of an OCH3intermediate bonded to Au atoms.Studies using isotope-labeling and analysis by gas chromatograph-mass(GC-MS)demonstrated that13CO_(2)was the source for photoelectrocatalytic generation of13CH3OH and13CH313CH2OH. 展开更多
关键词 Cu_(2)o nanocubes PHoToELECTRoCATALYSIS PoLYDoPAMINE Co_(2) photoelectroreduction DFT calculations
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Linkage between precipitation isotopes and water vapor sources in the monsoon margin:Evidence from arid areas of Northwest China
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作者 CHEN Fenli ZHANG Qiuyan +3 位作者 WANG Shengjie CHEN Jufan GAO Minyan Mohd Aadil BHAT 《Journal of Arid Land》 SCIE CSCD 2024年第3期355-372,共18页
The isotope composition in precipitation has been widely considered as a tracer of monsoon activity.Compared with the coastal region,the monsoon margin usually has limited precipitation with large fluctuation and is u... The isotope composition in precipitation has been widely considered as a tracer of monsoon activity.Compared with the coastal region,the monsoon margin usually has limited precipitation with large fluctuation and is usually sensitive to climate change.The water resource management in the monsoon margin should be better planned by understanding the composition of precipitation isotope and its influencing factors.In this study,the precipitation samples were collected at five sampling sites(Baiyin City,Kongtong District,Maqu County,Wudu District,and Yinchuan City)of the monsoon margin in the northwest of China in 2022 to analyze the characteristics of stable hydrogen(δD)and oxygen(δ18O)isotopes.We analyzed the impact of meteorological factors(temperature,precipitation,and relative humidity)on the composition of precipitation isotope at daily level by regression analysis,utilized the Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)-based backward trajectory model to simulate the air mass trajectory of precipitation events,and adopted the potential source contribution function(PSCF)and concentration weighted trajectory(CWT)to analyze the water vapor sources.The results showed that compared with the global meteoric water line(GMWL),the slope of the local meteoric water line(LMWL;δD=7.34δ^(18)O-1.16)was lower,indicating the existence of strong regional evaporation in the study area.Temperature significantly contributed toδ18O value,while relative humidity had a significant negative effect onδ18O value.Through the backward trajectory analysis,we found eight primary locations that were responsible for the water vapor sources of precipitation in the study area,of which moisture from the Indian Ocean to South China Sea(ITSC)and the western continental(CW)had the greatest influence on precipitation in the study area.The hydrogen and oxygen isotopes in precipitation are significantly influenced by the sources and transportation paths of air mass.In addition,the results of PSCF and CWT analysis showed that the water vapor source areas were primarily distributed in the south and northwest direction of the study area. 展开更多
关键词 water vapor monsoon margin stable water isotope transport trajectory air mass d-excess Δ18o δD
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Designing ultrastable P2/O3-type layered oxides for sodium ion batteries by regulating Na distribution and oxygen redox chemistry
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作者 Jieyou Huang Weiliang Li +3 位作者 Debin Ye Lin Xu Wenwei Wu Xuehang Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期466-476,共11页
P2/O3-type Ni/Mn-based layered oxides are promising cathode materials for sodium-ion batteries(SIBs)owing to their high energy density.However,exploring effective ways to enhance the synergy between the P2 and 03 phas... P2/O3-type Ni/Mn-based layered oxides are promising cathode materials for sodium-ion batteries(SIBs)owing to their high energy density.However,exploring effective ways to enhance the synergy between the P2 and 03 phases remains a necessity.Herein,we design a P2/O3-type Na_(0.76)Ni_(0.31)Zn_(0.07)Mn_(0.50)Ti_(0.12)0_(2)(NNZMT)with high chemical/electrochemical stability by enhancing the coupling between the two phases.For the first time,a unique Na*extraction is observed from a Na-rich O3 phase by a Na-poor P2 phase and systematically investigated.This process is facilitated by Zn^(2+)/Ti^(4+)dual doping and calcination condition regulation,allowing a higher Na*content in the P2 phase with larger Na^(+)transport channels and enhancing Na transport kinetics.Because of reduced Na^(+)in the O3 phase,which increases the difficulty of H^(+)/Na^(+) exchange,the hydrostability of the O3 phase in NNZMT is considerably improved.Furthermore,Zn^(2+)/Ti^(4+)presence in NNZMT synergistically regulates oxygen redox chemistry,which effectively suppresses O_(2)/CO_(2) gas release and electrolyte decomposition,and completely inhibits phase transitions above 4.0 V.As a result,NNZMT achieves a high discharge capacity of 144.8 mA h g^(-1) with a median voltage of 3.42 V at 20 mA g^(-1) and exhibits excellent cycling performance with a capacity retention of 77.3% for 1000 cycles at 2000 mA g^(-1).This study provides an effective strategy and new insights into the design of high-performance layered-oxide cathode materials with enhanced structure/interface stability forSIBs. 展开更多
关键词 Sodium-ion batteries P2/o3-type layered oxides Na distribution oxygen redox chemistry Hydrostability
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Effects of Coagulation and Ozonation Pretreatments on Biochemical Treatment of Fluid Catalytic Cracking Wastewater
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作者 Ibrah Landi Ali Lu Jun 《Journal of Environmental Protection》 2024年第2期156-172,共17页
Fluid catalytic cracking (FCC) salty wastewaters, containing quaternary ammonium compounds (QACs), are very difficult to treat by biochemical process. Anoxic/oxic (A/O) biochemical system, based on nitrification and d... Fluid catalytic cracking (FCC) salty wastewaters, containing quaternary ammonium compounds (QACs), are very difficult to treat by biochemical process. Anoxic/oxic (A/O) biochemical system, based on nitrification and denitrification reactions, was used to assess their possible biodegradation. Because of the negative effects of high salt concentration (3%), heavy metals and toxic organic matter on microorganisms’ activities, some techniques consisting of dilution, coagulation and flocculation, and ozonation pretreatments, were gradually tested to evaluate chemical oxygen demand (COD), ammonia-nitrogen (ammonia-N) and total nitrogen (TN) removal rates. In this process of FCC wastewater, starting with university-domesticated sludge, the ammonia-N and TN removal rates were worst. However, when using domesticated SBR’s sludge and operating with five-fold daily diluted influent (thus reducing salt concentration), the ammonia-N removal reached about 57% while the TN removal rate was less than 37% meaning an amelioration of the nitrification process. However, by reducing the dilution factors, these results were inflected after some days of operation, with ammonia-N removal decreasing and TN barely removed meaning a poor nitrification. Even by reducing heavy metals concentration with coagulation/flocculation process, the results never changed. Thereafter, by using ozonation pre-treatment to degrade the detected organic matter of di-tert-butylphenol and certain isoparaffins, COD, ammonia-N and TN removal rates reached 92%, 62% and 61%, respectively. These results showed that the activities of the microorganisms were increased, thus indicating a net denitrification and nitrification reactions improvement. 展开更多
关键词 Ammonia-N Anoxic and oxic (A/o) Reactor Coagulation and Sedimentation FCC Wastewater ozone Total Nitrogen (TN)
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Different El Niño Flavors and Associated Atmospheric Teleconnections as Simulated in a Hybrid Coupled Model
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作者 Junya HU Hongna WANG +1 位作者 Chuan GAO Rong-Hua ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期864-880,共17页
A previously developed hybrid coupled model(HCM)is composed of an intermediate tropical Pacific Ocean model and a global atmospheric general circulation model(AGCM),denoted as HCMAGCM.In this study,different El Ni... A previously developed hybrid coupled model(HCM)is composed of an intermediate tropical Pacific Ocean model and a global atmospheric general circulation model(AGCM),denoted as HCMAGCM.In this study,different El Niño flavors,namely the Eastern-Pacific(EP)and Central-Pacific(CP)types,and the associated global atmospheric teleconnections are examined in a 1000-yr control simulation of the HCMAGCM.The HCMAGCM indicates profoundly different characteristics among EP and CP El Niño events in terms of related oceanic and atmospheric variables in the tropical Pacific,including the amplitude and spatial patterns of sea surface temperature(SST),zonal wind stress,and precipitation anomalies.An SST budget analysis indicates that the thermocline feedback and zonal advective feedback dominantly contribute to the growth of EP and CP El Niño events,respectively.Corresponding to the shifts in the tropical rainfall and deep convection during EP and CP El Niño events,the model also reproduces the differences in the extratropical atmospheric responses during the boreal winter.In particular,the EP El Niño tends to be dominant in exciting a poleward wave train pattern to the Northern Hemisphere,while the CP El Niño tends to preferably produce a wave train similar to the Pacific North American(PNA)pattern.As a result,different climatic impacts exist in North American regions,with a warm-north and cold-south pattern during an EP El Niño and a warm-northeast and cold-southwest pattern during a CP El Niño,respectively.This modeling result highlights the importance of internal natural processes within the tropical Pacific as they relate to the genesis of ENSO diversity because the active ocean–atmosphere coupling is allowed only in the tropical Pacific within the framework of the HCMAGCM. 展开更多
关键词 hybrid coupled model tropical Pacific ocean global atmosphere Eastern/Central-Pacific El Niño atmospheric teleconnections
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