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High-throughput calculation-based rational design of Fe-doped MoS_(2) nanosheets for electrocatalytic p H-universal overall water splitting
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作者 Guangtong Hai Xiangdong Xue +3 位作者 Zhenyu Wu Canyang Zhang Xin Liu Xiubing Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期194-202,共9页
Electrocatalytic water splitting is crucial for H2generation via hydrogen evolution reaction(HER)but subject to the sluggish dynamics of oxygen evolution reaction(OER).In this work,single Fe atomdoped MoS_(2)nanosheet... Electrocatalytic water splitting is crucial for H2generation via hydrogen evolution reaction(HER)but subject to the sluggish dynamics of oxygen evolution reaction(OER).In this work,single Fe atomdoped MoS_(2)nanosheets(SFe-DMNs)were prepared based on the high-throughput density functional theory(DFT)calculation screening.Due to the synergistic effect between Fe atom and MoS_(2)and optimized intermediate binding energy,the SFe-DMNs could deliver outstanding activity for both HER and OER.When assembled into a two-electrode electrolytic cell,the SFe-DMNs could achieve the current density of 50 mA cm^(-2)at a low cell voltage of 1.55 V under neutral condition.These results not only confirmed the effectiveness of high-throughput screening,but also revealed the excellent activity and thus the potential applications in fuel cells of SFe-DMNs. 展开更多
关键词 High-throughput calculation Overall water splitting Single atom doped catalyst Molybdenum disulfide nanosheet
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Trends of Land Use and Land Cover Change in the Savannah Ecological of the Protected Area Reserve Partielle de Dosso, Niger
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作者 Amadou Issoufou Abdourhimou Moussa Boubacar +2 位作者 Habou Rabiou Soumana Idrissa Mahamane Ali 《Natural Resources》 2024年第3期61-68,共8页
Information on the dynamics of savannah is important to a country's plan to overcome the problems of uncontrolled development and environmental hazards. Taking the reserve partielle de Dosso, Niger as the case stu... Information on the dynamics of savannah is important to a country's plan to overcome the problems of uncontrolled development and environmental hazards. Taking the reserve partielle de Dosso, Niger as the case study area, this paper analyzed the long-term land use land cover change from 2002 to 2022. Satellite images were processed by using Google Earth Engine (GEE). Therefore, four major land cover classes were identified based on spectral characteristics of Land sat, namely, built-up, vegetation, cropland, bare land and water. The result revealed that barren and built-up areas increased at the expense of vegetation and water. From the four major land use land cover the large area is covered by vegetation which comprises about 192963.5 hectares followed by cropland and water consisting of 32506.43 and 1596.4 hectares respectively. The built-up area gained substantial area (most) during the study period. The reduction in some of the land cover/uses underlines the dangerous trend of the pressure poised by population growth and the changing functionality. Land cover change is influenced by a variety of societal factors operating on several spatial and temporal levels. The area estimates and spatial distributions of the LULC classes produced from the current study will assist local authorities, managers, and other stakeholders in decision-making and planning regarding forest land cover and uses. 展开更多
关键词 Land Use/Cover Change Detection CLASSIFICATION Dosso
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Cross-sectional associations between cortical thiclmess and physical activity in older adults with spontaneous memory complaints:The MAPT Study
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作者 Jérémy Raffin Yves Rolland +5 位作者 Clara Fischer Jean-Francois Mangin Audrey Gabelle Bruno Vellas Philipe de Souto Barreto the MAPT/DSA Group 《Journal of Sport and Health Science》 SCIE CSCD 2023年第3期324-332,共9页
Background:Age-related changes in brain structure may constitute the starting point for cerebral function alteration.Physical activity(PA)demonstrated favorable associations with total brain volume,but its relationshi... Background:Age-related changes in brain structure may constitute the starting point for cerebral function alteration.Physical activity(PA)demonstrated favorable associations with total brain volume,but its relationship with cortical thickness(CT)remains unclear.We investigated the cross-sectional associations between PA level and CT in community-dwelling people aged 70 years and older.Methods:A total of 403 older adults aged 74.8±4.0 years(mean±SD)who underwent a baseline magnetic resonance imaging examination and who had data on PA and confounders were included.PA was assessed with a questionnaire.Participants were categorized according to PA levels.Multiple linear regressions were used to compare the brain CT(mm)of the inactive group(no PA at all)with 6 active groups(growing PA levels)in 34 regions of interest.Results:Compared with inactive persons,people who achieved PA at a level of 1500-1999 metabolic equivalent task-min/week(i.e.,about6-7 h of brisk walking for exercise) and those who achieved it at 2000-2999 metabolic equivalent task-min/week(i.e.,8-11 h of brisk walking for exercise)had higher CT in the fusiform gyrus and the temporal pole.Additionally,dose-response associations between PA and CT were found in the fusiform gyrus(B=0.011,SE=0.004,adj.p=0.035),the temporal pole(B=0.026,SE=0.009,adj.p=0.048),and the caudal middle frontal gyrus,the entorhinal,medial orbitofrontal,lateral occipital,and insular cortices.Conclusion:This study demonstrates a positive association between PA level and CT in temporal areas such as the fusiform gyrus,a brain region often associated to Alzheimer’s disease in people aged 70 years and older.Future investigations focusing on PA type may help to fulfil remaining knowledge gaps in this field. 展开更多
关键词 Alzheimer's disease Brain aging Cortical thickness Physical activity
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Associations between physical activity levels and ATPase inhibitory factor 1 concentrations in older adults
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作者 Jérémy Raffin Yves Rolland +8 位作者 Annelise Genoux Guillaume Combes Mikael Croyal Bertrand Perret Sophie Guyonnet Bruno Vellas Laurent O.Martinez Philipe de Souto Barreto For the MAPT/DSA Group 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第3期409-418,共10页
Background:Adenosine triphosphatase inhibitory factor 1(IF1)is a key protein involved in energy metabolism.IF1 has been linked to various agerelated diseases,although its relationship with physical activity(PA)remains... Background:Adenosine triphosphatase inhibitory factor 1(IF1)is a key protein involved in energy metabolism.IF1 has been linked to various agerelated diseases,although its relationship with physical activity(PA)remains unclear.Additionally,the apolipoprotein A-I(apoA-I),a PA-modulated lipoprotein,could play a role in this relationship because it shares a binding site with IF1 on the cell-surface ATP synthase.We examined here the associations between chronic PA and plasma IF1 concentrations among older adults,and we investigated whether apoA-I mediated these associations.Methods:In the present work,1096 healthy adults(63.8%females)aged 70 years and over who were involved in the Multidomain Alzheimer Prevention Trial study were included.IF1 plasma concentrations(square root of ng/mL)were measured at the 1-year visit of the Multidomain Alzheimer Prevention Trial,while PA levels(square root of metabolic equivalent task min/week)were assessed using questionnaires administered each year from baseline to the 3-year visit.Multiple linear regressions were performed to investigate the associations between the first-year mean PA levels and IF1 concentrations.Mediation analyses were conducted to examine whether apoA-I mediated these associations.Mixedeffect linear regressions were carried out to investigate whether the 1-year visit IF1 concentrations predicted subsequent changes in PA.Results:Multiple linear regressions indicated that first-year mean PA levels were positively associated with IF1 concentrations(B=0.021;SE=0.010;p=0.043).Mediation analyses revealed that about 37.7%of this relationship was mediated by apoA-I(B_(ab)=0.008;SE=0.004;p=0.023).Longitudinal investigations demonstrated that higher concentrations of IF1 at the 1-year visit predicted a faster decline in PA levels over the subsequent 2 years(time×IF1:B=0.148;SE=0.066;p=0.025).Conclusion:This study demonstrates that regular PA is associated with plasma IF1 concentrations,and it suggests that apoA-I partly mediates this association.Additionally,this study finds that baseline concentrations of IF1 can predict future changes in PA.However,further research is needed to fully understand the mechanisms underlying these observations. 展开更多
关键词 Aging APOLIPOPROTEIN BIOENERGETICS Exerkine MITOCHONDRIA
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Construction of MnS/MoS_(2) heterostructure on two-dimensional MoS_(2) surface to regulate the reaction pathways for high-performance Li-O_(2) batteries
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作者 Guoliang Zhang Han Yu +6 位作者 Xia Li Xiuqi Zhang Chuanxin Hou Shuhui Sun Yong Du Zhanhu Guo Feng Dang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期443-452,I0012,共11页
The inherent catalytic anisotropy of two-dimensional(2D) materials has limited the enhancement of LiO_(2) batteries(LOBs) performance due to the significantly different adsorption energies on 2D and edge surfaces.Tuni... The inherent catalytic anisotropy of two-dimensional(2D) materials has limited the enhancement of LiO_(2) batteries(LOBs) performance due to the significantly different adsorption energies on 2D and edge surfaces.Tuning the adsorption strength in 2D materials to the reaction intermediates is essential for achieving high-performance LOBs.Herein,a MnS/MoS_(2) heterostructure is designed as a cathode catalyst by adjusting the adsorption behavior at the surface.Different from the toroidal-like discharge products on the MoS_(2) cathode,the MnS/MoS_(2) surface displays an improved adsorption energy to reaction species,thereby promoting the growth of the film-like discharge products.MnS can disturb the layer growth of MoS_(2),in which the stack edge plane features a strong interaction with the intermediates and limits the growth of the discharge products.Experimental and theoretical results confirm that the MnS/MoS_(2) heterostructure possesses improved electron transfer kinetics at the interface and plays an important role in the adsorption process for reaction species,which finally affects the morphology of Li_2O_(2),In consequence,the MnS/MoS_(2) heterostructure exhibits a high specific capacity of 11696.0 mA h g^(-1) and good cycle stability over 1800 h with a fixed specific capacity of 600 mA h g^(-1) at current density of100 mA g^(-1) This work provides a novel interfacial engineering strategy to enhance the performance of LOBs by tuning the adsorption properties of 2D materials. 展开更多
关键词 Li-O_(2)batteries Two-dimensional materials MnS/MoS_(2)heterostructure Edge plane Adsorption behavior
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Graphitic‐shell encapsulated FeNi alloy/nitride nanocrystals on biomass‐derived N‐doped carbon as an efficient electrocatalyst for rechargeable Zn‐air battery 被引量:8
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作者 Mingjie Wu Gaixia Zhang +5 位作者 Yongfeng Hu Jian Wang Tianxiao Sun Tom Regier Jinli Qiao Shuhui Sun 《Carbon Energy》 CAS 2021年第1期176-187,共12页
Oxygen reduction/evolution reactions(ORR/OERs)catalysts play a key role in the metal‐air battery and water‐splitting process.Herein,we developed a facile template‐free method to fabricate a new type of non–noble m... Oxygen reduction/evolution reactions(ORR/OERs)catalysts play a key role in the metal‐air battery and water‐splitting process.Herein,we developed a facile template‐free method to fabricate a new type of non–noble metal‐based hybrid catalyst which consists of binary FeNi alloy/nitride nanocrystals with graphitic‐shell and biomass‐derived N‐doped carbon(NC)(FexNiyN@C/NC).This novel nanostructure exhibits superior performance for ORR/OER,which can be attributed to the strong interactions between the graphitic‐shell encapsulated FeNi alloy/nitride nanocrystals and the N‐doped porous carbon substrate.The X‐ray absorption spectroscopy technique was employed to reveal the underlying mechanisms for the excellent performance.The assembled Zn‐air battery device exhibits outstanding charging/discharging performance and cycling stability,indicating the great potential of this type of novel catalysts. 展开更多
关键词 binary FeNi alloy/nitride N‐doped carbon oxygen reduction and evolution reactions X‐ray absorption spectroscopy Zn‐air battery
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Vanadium-dependent activation of glucose transport in adipocytes by catecholamines is not mediated via adrenoceptor stimulation or monoamine oxidase activity 被引量:2
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作者 Jessica Fontaine Geneviève Tavernier +1 位作者 Nathalie Morin Christian Carpéné 《World Journal of Diabetes》 SCIE 2020年第12期622-643,共22页
BACKGROUND Benzylamine and methylamine activate glucose uptake in adipocytes.For tyramine,this effect has even been extended to cardiomyocytes.AIM To investigate the effects of catecholamines and other amines on gluco... BACKGROUND Benzylamine and methylamine activate glucose uptake in adipocytes.For tyramine,this effect has even been extended to cardiomyocytes.AIM To investigate the effects of catecholamines and other amines on glucose uptake.METHODS A screening compared 25 biogenic amines on 2-deoxyglucose(2-DG)uptake activation in rat adipocytes.Pharmacological approaches and transgenic mouse models were then used to decipher the mode of action of several hits.RESULTS In rat adipocytes,insulin stimulation of 2-DG uptake was reproduced with catecholamines.100μmol/L or 1 mmol/L adrenaline,noradrenaline,dopamine and deoxyepinephrine,maximally activated hexose transport only when sodium orthovanadate was added at 100μmol/L.Such activation was similar to that already reported for benzylamine,methylamine and tyramine,well-recognized substrates of semicarbazide-sensitive amine oxidase(SSAO)and monoamine oxidase(MAO).Several,but not all,tested agonists ofβ-adrenoreceptors(β-ARs)also activated glucose transport whileα-AR agonists were inactive.Lack of blockade byα-andβ-AR antagonists indicated that catecholamine-induced 2-DG uptake was not mediated by AR stimulation.Adipocytes from mice lackingβ1-,β2-andβ3-ARs(triple KO)also responded to millimolar doses of adrenaline or noradrenaline by activating hexose transport in the presence of 100μmol/L vanadate.The MAO blocker pargyline,and SSAO inhibitors did not block the effects of adrenaline or noradrenaline plus vanadate,which were blunted by antioxidants.CONCLUSION Catecholamines exert unexpected insulin-like actions in adipocytes when combined with vanadium.For limiting insulin resistance by activating glucose consumption at least in fat stores,we propose that catecholamine derivatives combined with vanadium can generate novel complexes that may have low toxicity and promising anti-diabetic properties. 展开更多
关键词 ADIPOCYTE Amine oxidases INSULIN Diabetes VANADIUM Obesity
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Coupled thermo-hydro-mechanical simulation of CO2 enhanced gas recovery with an extended equation of state module for TOUGH2MP-FLAC3D 被引量:1
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作者 Yang Gou Zhengmeng Hou +2 位作者 Mengting Li Wentao Feng Hejuan Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2016年第6期904-920,共17页
As one of the most important ways to reduce the greenhouse gas emission,carbon dioxide(CO2)enhanced gas recovery(CO2-EGR) is attractive since the gas recovery can be enhanced simultaneously with CO2sequestration.B... As one of the most important ways to reduce the greenhouse gas emission,carbon dioxide(CO2)enhanced gas recovery(CO2-EGR) is attractive since the gas recovery can be enhanced simultaneously with CO2sequestration.Based on the existing equation of state(EOS) module of TOUGH2 MP,extEOS7C is developed to calculate the phase partition of H2O-CO2-CH4-NaCl mixtures accurately with consideration of dissolved NaCI and brine properties at high pressure and temperature conditions.Verifications show that it can be applied up to the pressure of 100 MPa and temperature of 150℃.The module was implemented in the linked simulator TOUGH2MP-FLAC3 D for the coupled hydro-mechanical simulations.A simplified three-dimensional(3D)1/4 model(2.2 km×1 km×1 km) which consists of the whole reservoir,caprock and baserock was generated based on the geological conditions of a gas field in the North German Basin.The simulation results show that,under an injection rate of 200,000 t/yr and production rate of 200,000 sm3/d,CO2breakthrough occurred in the case with the initial reservoir pressure of 5 MPa but did not occur in the case of 42 MPa.Under low pressure conditions,the pressure driven horizontal transport is the dominant process;while under high pressure conditions,the density driven vertical flow is dominant.Under the considered conditions,the CO2-EGR caused only small pressure changes.The largest pore pressure increase(2 MPa) and uplift(7 mm) occurred at the caprock bottom induced by only CO2injection.The caprock had still the primary stress state and its integrity was not affected.The formation water salinity and temperature variations of ±20℃ had small influences on the CO2-EGR process.In order to slow down the breakthrough,it is suggested that CO2-EGR should be carried out before the reservoir pressure drops below the critical pressure of CO2. 展开更多
关键词 Carbon dioxide (CO2) enhanced gas recovery (CO2-EGR) CO2 sequestration Equation of state (EOS) Coupled thermo-hydro-mechanical (THM) modeling TOUGH2MP-FLAC3D
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Location and Characterization of Breeding Sites of Solitary Desert Locust Using Satellite Images Landsat 7 ETM+ and Terra MODIS 被引量:2
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作者 Lazar Mohammed Aliou Diongue +2 位作者 Jeng-Tze Yang Doumandji-Mitiche Bahia Lecoq Michel 《Advances in Entomology》 2015年第1期6-15,共10页
In the southern Algerian Sahara, populations of the desert locust have been monitored during the past 43 years. On a limited study area, the use of remote sensing data from Landsat 7 ETM+ and Terra MODIS, coupled with... In the southern Algerian Sahara, populations of the desert locust have been monitored during the past 43 years. On a limited study area, the use of remote sensing data from Landsat 7 ETM+ and Terra MODIS, coupled with the locust population database, allowed the identification and mapping of solitary desert locust breeding areas during remission periods. These sites are mainly located in wadis and in areas of accumulation/spreading of rainwater. The use of this methodology to all the Algerian Sahara is surely possible in order to improve the preventive management of this pest. 展开更多
关键词 Desert LOCUST Schistocerca gregaria Remote Sensing MODIS LANDSAT Early WARNING
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Multichannel imaging for monitoring chemical composition and germination capacity of cowpea(Vigna unguiculata) seeds during development and maturation 被引量:1
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作者 Gamal ElMasry Nasser Mandour +5 位作者 Yahya Ejeez Didier Demilly Salim Al-Rejaie Jerome Verdier Etienne Belin David Rousseau 《The Crop Journal》 SCIE CSCD 2022年第5期1399-1411,共13页
This study aimed to set a computer-integrated multichannel spectral imaging system as a high-throughput phenotyping tool for the analysis of individual cowpea seeds harvested at different developmental stages. The cha... This study aimed to set a computer-integrated multichannel spectral imaging system as a high-throughput phenotyping tool for the analysis of individual cowpea seeds harvested at different developmental stages. The changes in germination capacity and variations in moisture, protein and different sugars during twelve stages of seed development from 10 to 32 days after anthesis were nondestructively monitored. Multispectral data at 20 discrete wavelengths in the ultraviolet, visible and near infrared regions were extracted from individual seeds and then modelled using partial least squares regression and linear discriminant analysis(LDA) models. The developed multivariate models were accurate enough for monitoring all possible changes occurred in moisture, protein and sugar contents with coefficients of determination in prediction R^(2) of 0.93, 0.80 and 0.78 and root mean square errors in prediction(RMSEP) of 6.045%, 2.236% and 0.890%, respectively. The accuracy of PLS models in predicting individual sugars such as verbascose and stachyose was reasonable with R~2 of 0.87 and 0.87 and RMSEP of 0.071%and 0.485%, respectively;but for the prediction of sucrose and raffinose the accuracy was relatively limited with R^(2) of 0.24 and 0.66 and RMSEP of 0.567% and 0.045%, respectively. The developed LDA model was robust in classifying the seeds based on their germination capacity with overall correct classification of96.33% and 95.67% in the training and validation datasets, respectively. With these levels of accuracy,the proposed multichannel spectral imaging system designed for single seeds could be an effective choice as a rapid screening and non-destructive technique for identifying the ideal harvesting time of cowpea seeds based on their chemical composition and germination capacity. Moreover, the development of chemical images of the major constituents along with classification images confirmed the usefulness of the proposed technique as a non-destructive tool for estimating the concentrations and spatial distributions of moisture, protein and sugars during different developmental stages of cowpea seeds. 展开更多
关键词 Multispectral imaging Multichannel imaging Chemical imaging Spectral analysis SEEDS COWPEA
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Insulin-mimetic compound hexaquis(benzylammonium) decavanadate is antilipolytic in human fat cells 被引量:2
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作者 Christian Carpéné Silvia Garcia-Vicente +6 位作者 Marta Serrano Luc Marti ChloéBelles Miriam Royo Jean Galitzky Antonio Zorzano Xavier Testar 《World Journal of Diabetes》 SCIE CAS 2017年第4期143-153,共11页
AIM To assess in rodent and human adipocytes the antilipolytic capacity of hexaquis(benzylammonium) decavanadate(B6V10), previously shown to exert antidiabetic effects in rodent models, such as lowering free fatty aci... AIM To assess in rodent and human adipocytes the antilipolytic capacity of hexaquis(benzylammonium) decavanadate(B6V10), previously shown to exert antidiabetic effects in rodent models, such as lowering free fatty acids(FFA) and glucose circulating levels.METHODS Adipose tissue(AT) samples were obtained after informed consent from overweight women undergoing plastic surgery. Comparison of the effects of B6V10 and reference antilipolytic agents(insulin,benzylamine,vanadate) on the lipolytic activity was performed on adipocytes freshly isolated from rat, mouse and human AT. Glycerol release was measured using colorimetric assay as an index of lipolytic activity. The influence of B6V10 and reference agents on glucose transport into human fat cells was determined using the radiolabelled 2-deoxyglucose uptake assay.RESULTS In all the species studied, B6V10 exhibited a dosedependent inhibition of adipocyte lipolysis when triglyceride breakdown was moderately enhanced by β-adrenergic receptor stimulation. B6V10 exerted on human adipocyte a maximal lipolysis inhibition of glycerol release that was stronger than that elicited by insulin. However, B6V10 did not inhibit basal and maximally stimulated lipolysis. When incubated at dose ≥ 10 μmol/L, B6V10 stimulated by twofold the glucose uptake in human fat cells, but-similarly to benzylamine-without reaching the maximal effect of insulin, while it reproduced one-half of the insulin-stimulation of lipogenesis in mouse fat cells. CONCLUSION B6V10 exerts insulin-like actions in adipocytes, including lipolysis inhibition and glucose transport activation. B6V10 may be useful in limiting lipotoxicity related to obesity and insulin resistance. 展开更多
关键词 ADIPOCYTE 分解 oxidases 胰岛素抵抗 肥胖 氢过氧化物 ANTIDIABETICS
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First-principle calculation of distorted T-carbon as a promising anode for Li-ion batteries with enhanced capacity, reversibility, and ion migration properties 被引量:1
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作者 Jianrui Feng Chao Yang +3 位作者 Lijie Zhang Feili Lai Lei Du Xiaohua Yang 《Carbon Energy》 CAS 2020年第4期614-623,共10页
Carbon group element-based materials are the most widely used anode materials for Li-ion batteries(LIBs).However,their performance is limited by the low capacity(eg,graphite)or high-volume changes(eg,Si and Sn).Theref... Carbon group element-based materials are the most widely used anode materials for Li-ion batteries(LIBs).However,their performance is limited by the low capacity(eg,graphite)or high-volume changes(eg,Si and Sn).Therefore,exploring high-performance anode materials is quite appealing and promising.By first-principle calculations in this study,we found that distorted T-carbon(DTC)as a desired LIB anode shows properties of the enhanced capacity,decreased volume change,and the increased ion migration.The origin of such improved properties is attributed to the interconnected tunnels and large cavities of the carbon skeleton.The theoretical specific capacity of DTC is found to be 558 mAh/g,which is 1.5 times higher than that of commercial graphite anodes.Interestingly,the volume change of the DTC anode is only 3%at the full-lithiation state(one-fifth of that of the commercial graphite anode),which can overcome the pulverization problem in most high-capacity anode materials and attain a longer cycling lifetime.Both transition state calculations and molecular dynamics simulations demonstrate that the Li-ion migration barrier is less than 0.1 eV and the Li-ion vacancy is only 0.2 eV,enabling its promising rate performance.This study provides a new and effective strategy to improve the anode properties of LIBs. 展开更多
关键词 density functional theory Li-ion batteries molecular dynamics nanomaterials T-carbon
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Performance of Moroccan Wheat Cultivars under Tillage Systems and Water Regimes 被引量:1
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作者 A. Ramdani R. Mrabet H. Gdmez Macpberson 《Journal of Agricultural Science and Technology》 2010年第5期106-111,共6页
关键词 面包小麦品种 摩洛哥 水分条件 耕作制 相关性状 耕作系统 性能 产量优势
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Phenological stage effect on phenolic composition and repellent potential of Mentha pulegium against Tribolium castaneum and Lasioderma serricorne
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作者 Nidhal Salem Jazia Sriti +11 位作者 Olfa Bachrouch Kamel Msaada Saber Khammassi Majdi Hammami Saoussen Selmi Emna Boushih Marwa Ouertani Nesrine Hachani Manef Abderraba Brahim Marzouk Ferid Limam Jouda Mediouni Ben Jemaa 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2018年第4期207-216,共10页
Objective:To elucidate for the first time the phenological stage effect on polyphenol,flavonoid and proanthocyanidin contents of pennyroyal(Mentha pulegium)as well as their antioxidant capacities and insecticidal pote... Objective:To elucidate for the first time the phenological stage effect on polyphenol,flavonoid and proanthocyanidin contents of pennyroyal(Mentha pulegium)as well as their antioxidant capacities and insecticidal potentials against Tribolium castaneum and Lasioderma serricorne.Methods:Crude methanol extracts from pennyroyal(Mentha pulegium)aerial parts were evaluated for their anti radical,reducing power activities and repellent potentials against selected coleopteran insects during different phenological stages.Results:Phenolic contents of pennyroyal aerial parts and their antioxidant effects were significantly dependent on maturity stage of the plant.The maximum of phenol production was reached during the full flowering stage.Apigenin was the major phenol in Mentha pulegium with an amount of6.01 mg/g of dry vegetable matter during this period.Nevertheless,at fructification stage,the highest antioxidant activity was not related to high phenolic content.The repulsive effect of pennyroyal extract showed that Lasioderma serricorne was more susceptible to pennyroyal extract than Tribolium castarneum with corresponding median repellent dose values of 0.124and 0.006 mg/mL respectively.Moreover,great differences in insect repulsion depending on extract concentrations,exposure time and developmental stage was observed.For the lowest concentration(0.125 mg/mL),the repellent effect against Tribolium reached its maximum(90%)during the fructification stage(after 24 h of exposure)while this repellent effect was 80%during the vegetative stage.Conclusions:Due to the strong insecticidal potential of pennyroyal extracts,this study highlights the therapeutic properties of this plant and encourages its use as a safer,environmental-friendly and efficient insecticide in food industry. 展开更多
关键词 APIGENIN Lasioderma Repellent activity Full flowering stage
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Advanced semiconductor catalyst designs for the photocatalytic reduction of CO_(2) 被引量:2
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作者 Zhangsen Chen Gaixia Zhang +3 位作者 Siyi Cao Guozhu Chen Cuncheng Li Ricardo IzquierdoShuhui Sun 《Materials Reports(Energy)》 2023年第2期27-42,I0002,共17页
Using clean solar energy to reduce CO_(2)into value-added products not only consumes the over-emitted CO_(2)that causes environmental problems,but also generates fuel chemicals to alleviate energy crises.The photocata... Using clean solar energy to reduce CO_(2)into value-added products not only consumes the over-emitted CO_(2)that causes environmental problems,but also generates fuel chemicals to alleviate energy crises.The photocatalytic CO_(2)reduction reaction(PCO_(2)RR)relies on the semiconductor photocatalysts that suffer from high recombination rate of the photo-generated carriers,low light harvesting capability,and low stability.This review explores the recent discoveries on the novel semiconductors for PCO_(2)RR,focusing on the rational catalyst design strategies(such as surface engineering,band engineering,hierarchical structure construction,single-atom catalysts,and biohybrid catalysts)that promote the catalytic performance of semiconductor catalysts on PCO_(2)RR.The advanced characterization techniques that contribute to understanding the intrinsic properties of the photocatalysts are also discussed.Lastly,the perspectives on future challenges and possible solutions for PCO_(2)RR are presented. 展开更多
关键词 Photoreduction of CO_(2) Semiconductor catalysts Photocatalyst modification Heterojunction construction Catalytic efficiency Activity Environmental and sustainable applications
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Millimeter-Wave Heterodyne Six-Port Receiver:New Implementation and Demodulation Results
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作者 D.Hammou E.Moldovan S.O.Tatu 《ZTE Communications》 2011年第3期42-48,共7页
This paper presents a new implementation of a millimeter-wave heterodyne receiver based on six-port technology. The six-port model is implemented in Advanced Design System (ADS) using S-parameter measurements for re... This paper presents a new implementation of a millimeter-wave heterodyne receiver based on six-port technology. The six-port model is implemented in Advanced Design System (ADS) using S-parameter measurements for realistic advanced simulation of a short-range 60 GHz wireless link. Millimeter-wave frequency conversion is performed using a six-port down-converter. The second frequency conversion is performed using conventional means because of low IF. A comparison between the proposed receiver and a conventional balanced millimeter-wave mixer shows that the proposed receiver improves conversion loss and I/Q phase stability over the local oscillator (LO) and RF power ranges. The results of demodulating a V-band quadrature phase-shift keying (QPSK) signal at a high data rate of 100 Mb/s-1 Gb/s are discussed. The results of a bit error rate (BER) and error vector magnitude (EVM) analysis prove that the proposed architecture can be successfully used for wireless link transmission up to 10 m. 展开更多
关键词 millimeter wave SIX-PORT frequency conversion HETERODYNE FRONT-END wireless LAN
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Photocatalytic Degradation of Paraquat Herbicide Using a Fixed Bed Reactor Containing TiO<sub>2</sub>Nanoparticles Coated onto <i>β-SiC</i>Alveolar Foams
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作者 Ignace Christian M’Bra Grah Patrick Atheba +2 位作者 Didier Robert Patrick Drogui Albert Trokourey 《American Journal of Analytical Chemistry》 2019年第5期171-184,共14页
Photocatalytic degradation of paraquat (PQ) aqueous solutions was studied in a fixed bed photoreactor under UV irradiation at 368 nm. This contained β-SiC alveolar foams coated with TiO2 P25 by dip-coating method. SE... Photocatalytic degradation of paraquat (PQ) aqueous solutions was studied in a fixed bed photoreactor under UV irradiation at 368 nm. This contained β-SiC alveolar foams coated with TiO2 P25 by dip-coating method. SEM analyses revealed that the surface of the film did not exhibit cracks in the presence of TTIP as a binder in the TiO2 P25 suspension. The following parameters were studied in continuous mode operation: the flow rate in the reactor, the initial concentration of the paraquat, the pH of the solution, the weight of photocatalytic material with the number of foams in the reactor and the weight of the catalyst deposited onto the support. The results showed that by working under optimal operating conditions at natural pH (pH = 6.7), low paraquat (Co = 10 ppm), and flow (26 mL/min), we recorded approximately (43.16 ± 1.00)% oxidation of paraquat and a decrease in total organic carbon (TOC) of (27.13 ± 1.00)% after about 70 minutes. The apparent rate constant is in the order of (0.0656 ± 0.0010) min-1. In addition, by increasing the amount of β-SiC foams coated with TiO2, we improve the degradation of paraquat in the same order. The study of aging of the material showed its stability over time. However, photocatalytic activity was limited after 20 minutes of UV irradiation due to the limitation of the diffusion of the paraquat molecules towards the surface of the photocatalyst. As an outcome, we obtained an efficient TiO2/β-SiC material for photocatalytic degradation of organic compounds in water. 展开更多
关键词 Photocatalytic Degradation PARAQUAT Β-SIC Foam TiO2 P25 Water
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In-Vitro Evaluation of Resistance to Late Blight (Phytophthora infestans Mont. De Bary.) in Solanum Accessions Native to Chile, by Inoculation of Detached Leaflets
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作者 Jaime Solano Ivette Acuña +1 位作者 Jean-Eric Chauvin Philippe Brabant 《American Journal of Plant Sciences》 2016年第3期581-589,共9页
The objective of the present study was to evaluate the resistance of 10 accessions to P. infestans, by in-vitro inoculation of detached leaflets with a complex isolation of the fungus. Late blight, caused by the fungu... The objective of the present study was to evaluate the resistance of 10 accessions to P. infestans, by in-vitro inoculation of detached leaflets with a complex isolation of the fungus. Late blight, caused by the fungus Phytophthora infestans Mont. De Bary, is one of the most important diseases of the potato crop, and can destroy complete plantations in a short space of time. Chile is considered as a sub-centre of the origin of cultivated potatoes with many native potato varieties in the country. The different resistance components demonstrated that within the material of Chilean native Solanum, there was a wide range of variation to late blight. The resistant control (R-8906384) and the accessions UCT-34-Cor presented the lowest infection efficiency, small sizes of the lesions and low levels of sporulation classifying them as the most resistant. This suggests low efficiency of the infection and high resistance to penetration in these materials. The more susceptible accessions often presented a good level of resistance for one or few components. It would be of great interest to go into the genetic control of the different resistance components to know if the same level of resistance expressed for a component by different accessions is under the same genetic control or not. 展开更多
关键词 Late Blight Resistance Potato Germplasm Genetic Variability
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Light-controlled phosphorylation in the TrkA-Y785 site by photosensitive UAAs activates the MAPK/ERK signaling pathway
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作者 SHU ZHAO SHIXIN YE 《BIOCELL》 SCIE 2023年第6期1377-1388,共12页
Background:This paper aims to establish a light-controlled phosphorylation detection method at the Y785 site of tropomyosin receptor kinase A(TrkA)receptor in mammalian cells by using genetic code expansion technology... Background:This paper aims to establish a light-controlled phosphorylation detection method at the Y785 site of tropomyosin receptor kinase A(TrkA)receptor in mammalian cells by using genetic code expansion technology and detecting the effects of optical activation of this site on the downstream MAPK/ERK pathway.The study is based on the current situation that the regulatory mechanism of TrkA phosphorylation has not been fully elucidated.Methods:Two photosensitive unnatural amino acids,p-azido-L-phenylalanine(AzF)and photo-caged tyrosine(ONB)were introduced into the TrkA-Y785 site by genetic code expansion technology and site-directed mutagenesis.Western blotting and laser confocal imaging were conducted to analyze the effects of this site on activating the MAPK/ERK pathway and nerve cell differentiation before and after photostimulation.Results:Our results supplemented the light-controlled results of the TrkA-Y785 site based on our previous research and verified that Y785 also makes important contributions in regulating the MAPK/ERK pathway.Conclusion:This study demonstrated the significant contributions of the TrkAY785 site in regulating the ERK pathway by precisely controlling the phosphorylation state of a single tyrosine site. 展开更多
关键词 Tropomyosin receptor kinase A Genetic code expansion Y785 P-azido-L-phenylalanine Photo-caged tyrosine
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3D Grid of Carbon Tubes with Mn3O4-NPs/CNTs Filled in their Inner Cavity as Ultrahigh-Rate and Stable Lithium Anode
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作者 Shiping Zhang Fangming Han +7 位作者 Qijun Pan Dou Lin Xiaoguang Zhu Cheng Shao Gaixia Zhang Zhaoming Wang Shuhui Sun Guowen Meng 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期187-194,共8页
Transition metal oxides are regarded as promising candidates of anode for next-generation lithium-ion batteries(LIBs)due to their ultrahigh theoretical capacity and low cost,but are restricted by their low conductivit... Transition metal oxides are regarded as promising candidates of anode for next-generation lithium-ion batteries(LIBs)due to their ultrahigh theoretical capacity and low cost,but are restricted by their low conductivity and large volume expansion during Li^(+)intercalation.Herein,we designed and constructed a structurally integrated 3D carbon tube(3D-CT)grid film with Mn_(3)O_(4)nanoparticles(Mn_(3)O_(4)-NPs)and carbon nanotubes(CNTs)filled in the inner cavity of CTs(denoted as Mn_(3)O_(4)-NPs/CNTs@3D-CT)as high-performance free-standing anode for LIBs.The Mn_(3)O_(4)-NPs/CNTs@3D-CT grid with Mn_(3)O_(4)-NPs filled in the inner cavity of 3D-CT not only afford sufficient space to overcome the damage caused by the volume expansion of Mn_(3)O_(4)-NPs during charge and discharge processes,but also achieves highly efficient channels for the fast transport of both electrons and Li+during cycling,thus offering outstanding electrochemical performance(865 mAh g^(-1)at 1 A g^(-1)after 300 cycles)and excellent rate capability(418 mAh g^(-1)at 4 A g^(-1))based on the total mass of electrode.The unique 3D-CT framework structure would open up a new route to the highly stable,high-capacity,and excellent cycle and high-rate performance free-standing electrodes for highperformance Li-ion storage. 展开更多
关键词 3D interconnected carbon tube arrays ANODE FREE-STANDING Mn_(3)O_(4)
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