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Fracture of the Humeral Palette in Adult Patient: Therapeutic and Evolutive Aspect at Gabriel Touré Hospital: About 35 Cases
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作者 Mahamadou Diallo Abdoul Kadri Moussa +10 位作者 Kalifa Coulibaly Layes Touré Mahamadou Dama Mamadou Bassirou Traoré Cheick Oumar Sanogo Terna Traoré Famakan Doumbia Mamadou Diallo Amadou Maiga Adégné Pierre Togo Tiéman Coulibaly 《Surgical Science》 2023年第4期271-276,共6页
Introduction: Fractures of the humeral pallet occur between the distal insertion of the anterior brachial muscle and the joint space of the elbow. It represents 2% of all elbow fractures. These lower humeral fractures... Introduction: Fractures of the humeral pallet occur between the distal insertion of the anterior brachial muscle and the joint space of the elbow. It represents 2% of all elbow fractures. These lower humeral fractures present a therapeutic challenge to trauma. These fractures are in the majority of joint cases and can be accompanied by loss of substance, which makes their functional prognosis random despite the application of the main therapeutic principles: exact reduction with possible bone graft;stable osteosynthesis, usually allowing early rehabilitation. This work focused on identifying therapeutic aspects and assessing treatment outcomes. Material and Methods: This was a descriptive cross-sectional study of patients with a fracture of the humeral palette from January 2015 to December 2019 at the Orthopaedic Trauma Department CHU Gabriel Touré Bamako. Results: We collected 35 cases of fractures of the humeral palette. The average age was 39.25 years with extremes of 22 and 74 years. The male gender predominated (71.4%) with a sex ratio of 2.5. Etiologies were dominated by falls with 19 cases (54.3%) and stroke with 13 cases (37.1%). The standard X-ray of the face and profile of the elbow was performed in all our patients. The most frequent types of anatomoradiology were supra condylar fractures type A in 16 cases (45.7%), supra and inter condylar fractures type C in 15 cases (42.9%);4 cases of uni condylar fractures type B (11.4%). Associated lesions were observed in 42.85%. Surgical treatment was performed in 80% of cases. Complications were dominated by elbow stiffness in 18 cases (51.42%), secondary displacement in 5 cases (14.28%), ossifications in 4 cases (11.42%). At an average decrease of 3.2 years our results were considered good in 45.7%. Conclusion: Fractures of the humeral palette are relatively common with associated lesions. The complexity of the fracture with associated lesions makes treatment difficult with unpredictable evolution. 展开更多
关键词 FRACTURE Humeral Palette Anatomopathology Treatment Evolution Bamako MALI
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Evolutive Neural Net Fuzzy Filtering: Basic Description 被引量:1
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作者 Juan C. García Infante J. Jesús Medel Juárez Juan C. Sánchez García 《Journal of Intelligent Learning Systems and Applications》 2010年第1期12-18,共7页
The paper describes the operation principles of the evolutive neuro fuzzy filtering (ENFF) properties, which based on back propagation fuzzy neural net, this filter adaptively choose and emit a decision according with... The paper describes the operation principles of the evolutive neuro fuzzy filtering (ENFF) properties, which based on back propagation fuzzy neural net, this filter adaptively choose and emit a decision according with the reference signal changes of an external reference process, in order to actualize the best correct new conditions updating a process. This neural net fuzzy filter mechanism selects the best parameter values into the knowledge base (KB), to update the filter weights giving a good enough answers in accordance with the reference signal in natural sense. The filter architecture includes a decision making stage using an inference into its structure to deduce the filter decisions in accordance with the previous and actual filter answer in order to updates the new decision with respect to the new reference system con-ditions. The filtering process states require that bound into its own time limit as real time system, considering the Ny-quist and Shannon criteria. The characterization of the membership functions builds the knowledge base in probabilis-tic sense with respect to the rules set inference to describe the reference system and deduce the new filter decision, per-forming the ENFF answers. Moreover, the paper describes schematically the neural net architecture and the deci-sion-making stages in order to integrate them into the filter architecture as intelligent system. The results expressed in formal sense use the concepts into the paper references with a simulation of the ENFF into a Kalman filter structure using the Matlab? tool. 展开更多
关键词 Digital FILTERS NEURO FUZZY SYSTEMS evolutive SYSTEMS REAL Time
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The Evolutive Law concerning Relationship between Economic Growth and Farmers' Income Increase in Xinjiang since the Reform and Opening-up:An Empirical Analysis of the VEC Model
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作者 Xiaojun LIU Junsheng DAI 《Asian Agricultural Research》 2013年第1期4-8,共5页
We select the per capita gross domestic product and rural residents' per capita net income in Xinjiang as the indicator variables to measure economic growth and farmers' income increase in Xinjiang, respective... We select the per capita gross domestic product and rural residents' per capita net income in Xinjiang as the indicator variables to measure economic growth and farmers' income increase in Xinjiang, respectively. We establish the cointegration equation, the vector error correction (VEC) model, and use the impulse response function to conduct empirical analysis of the evolutive law concerning relationship between economic growth and farmers' income increase in Xinjiang during the period 1978-2010. The results show that there is a cointegration relationship between economic growth in Xinjiang and farmers' income increase; the former plays an important role in promoting the latter, following the evolutive law "first intensify, then abate, intensify again, and finally become stable". We put the following policy recommendations: providing preferential policies for farmers, scientifically and rationally guiding the transfer of rural labor; improving the function of agriculture, increasing the proportion of non-farm income; gradually bridging the widening income gap between urban and rural areas, coordinating urban and rural development. 展开更多
关键词 Economic growth Farmers’ INCOME INCREASE evolutive
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Clinical, aetiological and evolutive aspects of West syndrome in Yaoundé(Cameroon)
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作者 Séraphin Nguefack Boniface Moifo +6 位作者 Andréas Chiabi Antoine Ledoux Defo Evelyn Mah Florence Fru Paul Cédric Mbonda Pierre Fernand Tchokoteu Elie Mbonda 《Open Journal of Pediatrics》 2013年第4期306-310,共5页
Background: West syndrome (WS) is an epileptic syndrome of the infant occurring between the 3rd and 12th months of life and characterized by the triad: infantile spasms in flexion, extension or mixed;global developmen... Background: West syndrome (WS) is an epileptic syndrome of the infant occurring between the 3rd and 12th months of life and characterized by the triad: infantile spasms in flexion, extension or mixed;global developmental delay;and hypsarrythmia on the electroencephalogram (EEG). Its incidence varies between 2.9 and 4.5 per 10,000 live births. West syndrome is caused by a brain dysfunction whose origins can be prenatal, neonatal and postnatal. Sometimes the aetiology is genetic or unknown. Purpose: To determine the main clinical, aetiological and major evolutive aspects of West syndrome in child neurology unit in a university-affiliated hospital in Yaoundé. Materials and Methods: It was a retrospective descriptive study conducted from September 2011 to January 2012 inthe child neurology unit of the Yaoundé gynaeco-obstetric and paediatric hospital. The medical records of 68 children followed for West syndrome (WS) in the service during the period from February 2008 to January 2012 (48 months) were used. All infants of 1- to 16-month-old with the diagnosis of WS were included. The diagnosis of WS was based on clinical evidence of spasm in flexion and/or in extension with global development delay, and EEG evidence of hypsarythmia or focal/multifocal epileptic abnormalities when hypsarythmia is absent. For each included infant, relevant medical history and complete physical examination were performed. The following data were collected and reported on a standardized questionnaire: prenatal, perinatal and postnatal past histories, age at onset of spasms, age at diagnosis, semiology of spasms, psychomotor development, the EEG and CT aspects and the evolutive modes of WS under treatment. Psychomotor development was assessed using theDenverdevelopmental screening test (DDST) which assesses the mental age compared to chronological age. Results: The age of onset of spasms varied between 1 and 16 months with a mean of 4.69 (±1.98) months. Males were highly represented with a sex ratio of 1.72. Flexion spasms were the most common clinical presentation (79.41%). 82.83% of the patients had a global developmental delay on the onset of spasms. Structural causes or symptomatic West syndrome was the most frequent presentation (77.94%). Perinatal aetiologies were highly represented (73.58%) with the main cause being neonatal asphyxia (55.88%). A hypsarrythmic tracing was found on the electroencephalogram (EEG) in 73.53% of cases. The most frequent CT abnormality was cortico-subcortical atrophy (38.24%). At the end of our study, global developmental delay persisted in 89.72%. Conclusion: The main aetiologies of West syndrome in our context are the sequelae of neonatal asphyxia and viral embryofoetopathies. There is a high incidence of associated global developmental delay. More prevention methods on risk factors for foetal distress and proper monitoring of deliveries to minimize severe neonatal asphyxia are indispensable. 展开更多
关键词 WEST SYNDROME EPILEPSY AETIOLOGY Evolution Cameroon
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Deformable Catalytic Material Derived from Mechanical Flexibility for Hydrogen Evolution Reaction 被引量:2
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作者 Fengshun Wang Lingbin Xie +7 位作者 Ning Sun Ting Zhi Mengyang Zhang Yang Liu Zhongzhong Luo Lanhua Yi Qiang Zhao Longlu Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期287-311,共25页
Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent year... Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent years,deformable catalysts for HER have made great progress and would become a research hotspot.The catalytic activities of deformable catalysts could be adjustable by the strain engineering and surface reconfiguration.The surface curvature of flexible catalytic materials is closely related to the electrocatalytic HER properties.Here,firstly,we systematically summarized self-adaptive catalytic performance of deformable catalysts and various micro–nanostructures evolution in catalytic HER process.Secondly,a series of strategies to design highly active catalysts based on the mechanical flexibility of lowdimensional nanomaterials were summarized.Last but not least,we presented the challenges and prospects of the study of flexible and deformable micro–nanostructures of electrocatalysts,which would further deepen the understanding of catalytic mechanisms of deformable HER catalyst. 展开更多
关键词 Deformable catalytic material Micro-nanostructures evolution Mechanical flexibility Hydrogen evolution reaction
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Thermo-hydro-poro-mechanical responses of a reservoir-induced landslide tracked by high-resolution fiber optic sensing nerves 被引量:3
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作者 Xiao Ye Hong-Hu Zhu +4 位作者 Gang Cheng Hua-Fu Pei Bin Shi Luca Schenato Alessandro Pasuto 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期1018-1032,共15页
Thermo-poro-mechanical responses along sliding zone/surface have been extensively studied.However,it has not been recognized that the potential contribution of other crucial engineering geological interfaces beyond th... Thermo-poro-mechanical responses along sliding zone/surface have been extensively studied.However,it has not been recognized that the potential contribution of other crucial engineering geological interfaces beyond the slip surface to progressive failure.Here,we aim to investigate the subsurface multiphysics of reservoir landslides under two extreme hydrologic conditions(i.e.wet and dry),particularly within sliding masses.Based on ultra-weak fiber Bragg grating(UWFBG)technology,we employ specialpurpose fiber optic sensing cables that can be implanted into boreholes as“nerves of the Earth”to collect data on soil temperature,water content,pore water pressure,and strain.The Xinpu landslide in the middle reach of the Three Gorges Reservoir Area in China was selected as a case study to establish a paradigm for in situ thermo-hydro-poro-mechanical monitoring.These UWFBG-based sensing cables were vertically buried in a 31 m-deep borehole at the foot of the landslide,with a resolution of 1 m except for the pressure sensor.We reported field measurements covering the period 2021 and 2022 and produced the spatiotemporal profiles throughout the borehole.Results show that wet years are more likely to motivate landslide motions than dry years.The annual thermally active layer of the landslide has a critical depth of roughly 9 m and might move downward in warmer years.The dynamic groundwater table is located at depths of 9e15 m,where the peaked strain undergoes a periodical response of leap and withdrawal to annual hydrometeorological cycles.These interface behaviors may support the interpretation of the contribution of reservoir regulation to slope stability,allowing us to correlate them to local damage events and potential global destabilization.This paper also offers a natural framework for interpreting thermo-hydro-poro-mechanical signatures from creeping reservoir bank slopes,which may form the basis for a landslide monitoring and early warning system. 展开更多
关键词 Reservoir landslide Thermo-hydro-poro-mechanical response Ultra-weak fiber bragg grating(UWFBG) subsurface evolution Engineering geological interface Geotechnical monitoring
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New Benthic Fossils from the Late Ediacaran Strata of Southwestern China 被引量:2
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作者 LIU Junping LI Ming +5 位作者 TANG Feng ZHAO Jiangtai SONG Sicun ZHOU Ying SONG Xiaohan REN Liudong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期311-323,共13页
The Jiangchuan Biota from the Jiucheng Member(Mb.)of the Dengying Formation(Fm.),discovered in Jiangchuan,eastern Yunnan,China,is marked by copious macrofossils at the apex of the Ediacaran strata.This fauna features ... The Jiangchuan Biota from the Jiucheng Member(Mb.)of the Dengying Formation(Fm.),discovered in Jiangchuan,eastern Yunnan,China,is marked by copious macrofossils at the apex of the Ediacaran strata.This fauna features benthic algae with varied holdfasts and other fossils of indeterminate taxonomic affinity and is compositionally unique compared to the Shibantan and Gaojiashan biotas of the Dengying Fm.and the Miaohe and Wenghui biotas of the Doushantuo Fm.,elsewhere in China.One novel benthic saccular macroalgal fossil,named here Houjiashania yuxiensis gen.and sp.nov.,from the Jiangchuan Biota is based on fossils that are sausage-shaped,elongate,tubular,ranging from 0.3 to 4 cm in length,and up to 0.8 cm in diameter.One terminus is blunt and rounded to an obtuse angle,the other is bent with a spread-out surface resembling a holdfast,suggesting a three-dimensional thallus.Thin,stipe-shaped outgrowths,likely vestiges of sessile saccular life forms,are prevalent in macroalgal fossils of analogous size and shape,as well as present brown algae Scytosiphonaceae,such as Colpomenia and Dactylosiphon.The new findings augment the diversity of benthic algae,such as those known from the Early Neoproterozoic Longfengshan Biota in North China.The benthic algal macrofossils in the Jiucheng Mb.add to knowledge of Late Ediacaran metaphyte diversification and offer more clues about the evolutionary positioning of primitive macroalgae.The co-occurrence of numerous planktonic and benthic multicellular algae and planktonic microbes might have facilitated ecologically the more extensive later Cambrian explosion evidenced by the Chengjiang Biota in Yunnan. 展开更多
关键词 paleophytology benthic saccular algae algal evolution NEOPROTEROZOIC Jiucheng Member Jiangchuan Biota Yunnan Province
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Oxygen‑Coordinated Single Mn Sites for Efficient Electrocatalytic Nitrate Reduction to Ammonia 被引量:2
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作者 Shengbo Zhang Yuankang Zha +8 位作者 Yixing Ye Ke Li Yue Lin Lirong Zheng Guozhong Wang Yunxia Zhang Huajie Yin Tongfei Shi Haimin Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期147-159,共13页
Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites... Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption spectroscopy.As a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(vs.reversible hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(vs.RHE)under ambient conditions.Further,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H cell.The in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites. 展开更多
关键词 Atomically dispersed Oxygen coordination Nitrate reduction reaction In situ spectroscopic studies Hydrogen evolution reaction
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Ionic liquid derived electrocatalysts for electrochemical water splitting 被引量:1
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作者 Tianhao Li Weihua Hu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期604-622,共19页
Hydrogen production from electrochemical water splitting is a promising strategy to generate green energy,which requires the development of efficient and stable electrocatalysts for the hydrogen evolution reaction and... Hydrogen production from electrochemical water splitting is a promising strategy to generate green energy,which requires the development of efficient and stable electrocatalysts for the hydrogen evolution reaction and the oxygen evolution reaction(HER and OER).Ionic liquids(ILs)or poly(ionic liquids)(PILs),containing heteroatoms,metal-based anions,and various structures,have been frequently involved as precursors to prepare electrocatalysts for water splitting.Moreover,ILs/PILs possess high conductivity,wide electrochemical windows,and high thermal and chemical stability,which can be directly applied in the electrocatalysis process with high durability.In this review,we focus on the studies of ILs/PILs-derived electrocatalysts for HER and OER,where ILs/PILs are applied as heteroatom dopants and metal precursors to prepare catalysts or are directly utilized as the electrocatalysts.Due to those attractive properties,IL/PIL-derived electrocatalysts exhibit excellent performance for electrochemical water splitting.All these accomplishments and developments are systematically summarized and thoughtfully discussed.Then,the overall perspectives for the current challenges and future developments of ILs/PILs-derived electrocatalysts are provided. 展开更多
关键词 Ionic liquid Electrochemical water splitting Hydrogen evolution reaction Oxygen evolution reaction
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Precisely Control Relationship between Sulfur Vacancy and H Absorption for Boosting Hydrogen Evolution Reaction 被引量:1
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作者 Jing Jin Xinyao Wang +4 位作者 Yang Hu Zhuang Zhang Hongbo Liu Jie Yin Pinxian Xi 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期14-24,共11页
Ef fective and robust catalyst is the core of water splitting to produce hydrogen.Here, we report an anionic etching method to tailor the sulfur vacancy(VS) of NiS_(2) to further enhance the electrocatalytic performan... Ef fective and robust catalyst is the core of water splitting to produce hydrogen.Here, we report an anionic etching method to tailor the sulfur vacancy(VS) of NiS_(2) to further enhance the electrocatalytic performance for hydrogen evolution reaction(HER). With the VS concentration change from 2.4% to 8.5%, the H* adsorption strength on S sites changed and NiS_(2)-VS 5.9% shows the most optimized H* adsorption for HER with an ultralow onset potential(68 m V) and has long-term stability for 100 h in 1 M KOH media. In situ attenuated-total-reflection Fourier transform infrared spectroscopy(ATR-FTIRS) measurements are usually used to monitor the adsorption of intermediates. The S-H* peak of the Ni S_(2)-VS 5.9% appears at a very low voltage, which is favorable for the HER in alkaline media. Density functional theory calculations also demonstrate the Ni S_(2)-VS 5.9% has the optimal |ΔG^(H*)| of 0.17 e V. This work offers a simple and promising pathway to enhance catalytic activity via precise vacancies strategy. 展开更多
关键词 Hydrogen evolution reaction S vacancies NANOSHEET H Adsorption
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Mg/MgO interfaces as efficient hydrogen evolution cathodes causing accelerated corrosion of additive manufactured Mg alloys:A DFT analysis 被引量:1
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作者 Man-Fai Ng Kai Xiang Kuah +1 位作者 Teck Leong Tan Daniel John Blackwood 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期110-119,共10页
The corrosion rates of additive-manufactured Mg alloys are higher than their as-cast counterparts,possibly due to increased kinetics for the hydrogen evolution reaction on secondary phases,which may include oxide incl... The corrosion rates of additive-manufactured Mg alloys are higher than their as-cast counterparts,possibly due to increased kinetics for the hydrogen evolution reaction on secondary phases,which may include oxide inclusions.Scanning Kelvin Probe Force Microscopy demonstrated that MgO inclusions could act as cathodes for Mg corrosion,but their low conductivity likely precludes this.However,the density of state calculations through density functional theory using hybrid HSE06 functional revealed overlapping electronic states at the Mg/MgO interface,which facilitates electron transfers and participates in redox reactions.Subsequent determination of the hydrogen absorption energy at the Mg/MgO interface reveals it to be an excellent catalytic site,with HER being found to be a factor of 23x more efficient at the interface than on metallic Mg.The results not only support the plausibility of the Mg/MgO interface being an effective cathode to the adjacent anodic Mg matrix during corrosion but also contribute to the understanding of the enhanced cathodic activities observed during the anodic dissolution of magnesium. 展开更多
关键词 MAGNESIUM Magnesium oxide Interface Hydrogen evolution DFT
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Valence electronic engineering of superhydrophilic Dy-evoked Ni-MOF outperforming RuO_(2) for highly efficient electrocatalytic oxygen evolution 被引量:1
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作者 Zhiyang Huang Miao Liao +6 位作者 Shifan Zhang Lixia Wang Mingcheng Gao Zuyang Luo Tayirjan Taylor Isimjan Bao Wang Xiulin Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期244-252,I0007,共10页
Tackling the problem of poor conductivity and catalytic stability of pristine metal-organic frameworks(MOFs) is crucial to improve their oxygen evolution reaction(OER) performance.Herein,we introduce a novel strategy ... Tackling the problem of poor conductivity and catalytic stability of pristine metal-organic frameworks(MOFs) is crucial to improve their oxygen evolution reaction(OER) performance.Herein,we introduce a novel strategy of dysprosium(Dy) doping,using the unique 4f orbitals of this rare earth element to enhance electrocatalytic activity of MOFs.Our method involves constructing Dy-doped Ni-MOF(Dy@Ni-MOF) nanoneedles on carbon cloth via a Dy-induced valence electronic perturbation approach.Experiments and density functional theory(DFT) calculations reveal that Dy doping can effectively modify the electronic structure of the Ni active centers and foster a strong electronic interaction between Ni and Dy.The resulting benefits include a reduced work function and a closer proximity of the d-band center to the Fermi level,which is conducive to improving electrical conductivity and promoting the adsorption of oxygen-containing intermediates.Furthermore,the Dy@Ni-MOF achieves superhydrophilicity,ensuring effective electrolyte contact and thus accelerating reaction kinetics,Ex-situ and in-situ analysis results manifest Dy_(2)O_(3)/NiOOH as the actual active species.Therefore,Dy@Ni-MOF shows impressive OER performance,significantly surpassing Ni-MOF.Besides,the overall water splitting device with Dy@NiMOF as an anode delivers a low cell voltage of 1.51 V at 10 mA cm^(-2) and demonstrates long-term stability for 100 h,positioning it as a promising substitute for precious metal catalysts. 展开更多
关键词 Dy@Ni-MOF Dy incorporation Electronic interaction SUPERHYDROPHILICITY Oxygen evolution reaction
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Durable Ru Nanocrystal with HfO_(2)Modification for Acidic Overall Water Splitting 被引量:1
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作者 Xiangkai Kong Jie Xu +1 位作者 Zhicheng Ju Changle Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期462-477,共16页
Durable and efficient bi-functional catalyst,that is capable of both oxygen evolution reaction and hydrogen evolution reaction under acidic condition,are highly desired for the commercialization of proton exchange mem... Durable and efficient bi-functional catalyst,that is capable of both oxygen evolution reaction and hydrogen evolution reaction under acidic condition,are highly desired for the commercialization of proton exchange membrane water electrolysis.Herein,we report a robust L-Ru/HfO_(2)heterostructure constructed via confining crystalline Ru nanodomains by HfO_(2)matrix.When assembled with a proton exchange membrane,the bi-functional L-Ru/HfO_(2)catalyst-based electrolyzer presents a voltage of 1.57 and 1.67 V to reach 100 and 300 mA cm^(-2)current density,prevailing most of previously reported Ru-based materials as well as commercial Pt/C||RuO_(2)electrolyzer.It is revealed that the synergistic effect of HfO_(2)modification and small crystalline domain formation significantly alleviates the over-oxidation of Ru.More importantly,this synergistic effect facilitates a dual-site oxide path during the oxygen evolution procedure via optimization of the binding configurations of oxygenated adsorbates.As a result,the Ru active sites maintain the metallic state along with reduced energy barrier for the rate-determining step(^(*)O→^(*)OOH).Both of water adsorption and dissociation(Volmer step)are strengthened,while a moderate hydrogen binding is achieved to accelerate the hydrogen desorption procedure(Tafel step).Consequently,the activity and stability of acidic overall water splitting are simultaneously enhanced. 展开更多
关键词 RUTHENIUM Hafnium dioxide Oxygen evolution catalysis ANTI-OXIDATION
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Experimental study on the effect of water absorption level on rockburst occurrence of sandstone 被引量:1
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作者 Dongqiao Liu Jie Sun +3 位作者 Pengfei He Manchao He Binghao Cao Yuanyuan Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期136-152,共17页
To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and ... To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and acoustic emission(AE)system are used to monitor the rockburst process.The effect of water on sandstone rockburst and the prevention mechanism of water on sandstone rockburst are analyzed from the perspective of energy and failure mode.The results show that the higher the ab-sorption degree,the lower the intensity of the rockburst after absorbing water on single side of sand-stone.This is reflected in the fact that with the increase in the water absorption level,the ejection velocity of rockburst fragments is smaller,the depth of the rockburst pit is shallower,and the AE energy is smaller.Under the water absorption level of 100%,the magnitude of rockburst intensity changes from medium to slight.The prevention mechanism of water on sandstone rockburst is that water reduces the capacity of sandstone to store strain energy and accelerates the expansion of shear cracks,which is not conducive to the occurrence of plate cracking before rockburst,and destroys the conditions for rockburst incubation. 展开更多
关键词 ROCKBURST Water Prevention effect Crack evolution
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Microwave shock motivating the Sr substitution of 2D porous GdFeO_(3) perovskite for highly active oxygen evolution 被引量:1
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作者 Jinglin Xian Huiyu Jiang +10 位作者 Zhiao Wu Huimin Yu Kaisi Liu Miao Fan Rong Hu Guangyu Fang Liyun Wei Jingyan Cai Weilin Xu Huanyu Jin Jun Wan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期232-241,I0006,共11页
The incorporation of partial A-site substitution in perovskite oxides represents a promising strategy for precisely controlling the electronic configuration and enhancing its intrinsic catalytic activity.Conventional ... The incorporation of partial A-site substitution in perovskite oxides represents a promising strategy for precisely controlling the electronic configuration and enhancing its intrinsic catalytic activity.Conventional methods for A-site substitution typically involve prolonged high-temperature processes.While these processes promote the development of unique nanostructures with highly exposed active sites,they often result in the uncontrolled configuration of introduced elements.Herein,we present a novel approach for synthesizing two-dimensional(2D)porous GdFeO_(3) perovskite with A-site strontium(Sr)substitution utilizing microwave shock method.This technique enables precise control of the Sr content and simultaneous construction of 2D porous structures in one step,capitalizing on the advantages of rapid heating and cooling(temperature~1100 K,rate~70 K s^(-1)).The active sites of this oxygen-rich defect structure can be clearly revealed through the simulation of the electronic configuration and the comprehensive analysis of the crystal structure.For electrocatalytic oxygen evolution reaction application,the synthesized 2D porous Gd_(0.8)Sr_(0.2)FeO_(3) electrocatalyst exhibits an exceptional overpotential of 294 mV at a current density of 10 mA cm^(-2)and a small Tafel slope of 55.85 mV dec^(-1)in alkaline electrolytes.This study offers a fresh perspective on designing crystal configurations and the construction of nanostructures in perovskite. 展开更多
关键词 2D materials PEROVSKITE MICROWAVE ELECTROCATALYSIS Oxygen evolution reaction
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Understanding the oxidation chemistry of Ti_(3)C_(2)T_(x)(MXene)sheets and their catalytic performances 被引量:1
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作者 Suvdanchimeg Sunderiya Selengesuren Suragtkhuu +9 位作者 Solongo Purevdorj Tumentsereg Ochirkhuyag Munkhjargal Bat-Erdene Purevlkham Myagmarsereejid Ashley DSlattery Abdulaziz SRBati Joseph GShapter Dorj Odkhuu Sarangerel Davaasambuu Munkhbayar Batmunkh 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期437-445,I0010,共10页
Transition metal carbides and nitrides(MXenes)nanosheets are attractive two-dimensional(2D)materials,but they suffer from oxidation/degradation issues during storage and/or applications due to their sensitivity to wat... Transition metal carbides and nitrides(MXenes)nanosheets are attractive two-dimensional(2D)materials,but they suffer from oxidation/degradation issues during storage and/or applications due to their sensitivity to water and oxygen.Despite the great research progress,the exact oxidation kinetics of Ti_(3)C_(2)T_(x)(MXene)and their final products after oxidation are not fully understood.Herein,we systematically tracked the oxidation process of few-layer Ti_(3)C_(2)T_(x) nanosheets in an aqueous solution at room temperature over several weeks.We also studied the oxidation effects on the electrocatalytic properties of Ti_(3)C_(2)T_(x) for hydrogen evolution reaction and found that the overpotential to achieve a current density of 10 mA cm^(-2)increases from 0.435 to 0.877 V after three weeks of degradation,followed by improvement to stabilized values of around 0.40 V after eight weeks.These results suggest that severely oxidized MXene could be a promising candidate for designing efficient catalysts.According to our detailed experimental characterization and theoretical calculations,unlike previous studies,black titanium oxide is formed as the final product in addition to white Ti(IV)oxide and disordered carbons after the complete oxidation of Ti_(3)C_(2)T_(x).This work presents significant advancements in better understanding of 2D Ti_(3)C_(2)T_(x)(MXene)oxidation and enhances the prospects of this material for various applications. 展开更多
关键词 2D materials MXene Chemical degradation CATALYSIS Hydrogen evolution reaction
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Carbon Emission Effects Driven by Evolution of Chinese Dietary Structure from 1987 to 2020 被引量:1
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作者 ZHU Yuanyuan ZHANG Yan ZHU Xiaohua 《Chinese Geographical Science》 SCIE CSCD 2024年第1期181-194,共14页
Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research ob... Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research object(data excluding Hong Kong,Macao and Taiwan) and used the carbon emission coefficient method to quantitatively measure the food carbon emissions from 1987–2020,then analyzed the carbon emission effects under the evolution of dietary structure.The results showed that during the study period,the Chinese dietary structure gradually changed to a high-carbon consumption pattern.The dietary structure of urban residents developed to a balanced one,while that of rural residents developed to a high-quality one.During the study period,the per capita food carbon emissions and total food consumption of Chinese showed an increasing trend.The per capita food carbon emissions of residents in urban and rural showed an overall upward trend.The total food carbon emissions in urban increased significantly,while that in rural increased first and then decreased.The influence of beef and mutton on carbon emissions is the highest in dietary structure.Compared with the balanced dietary pattern,the food carbon emissions of Chinese residents had not yet reached the peak,but were evolving to a high-carbon consumption pattern. 展开更多
关键词 dietary structure structural evolution carbon emission effects carbon neutrality China
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Pyridinic-N doping carbon layers coupled with tensile strain of FeNi alloy for activating water and urea oxidation 被引量:1
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作者 Guangfu Qian Wei Chen +5 位作者 Jinli Chen Li Yong Gan Tianqi Yu Miaojing Pan Xiaoyan Zhuo Shibin Yin 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期684-694,共11页
Exploitation of oxygen evolution reaction(OER)and urea oxidation reaction(UOR)catalysts with high activity and stability at large current density is a major challenge for energy-saving H_(2) production in water electr... Exploitation of oxygen evolution reaction(OER)and urea oxidation reaction(UOR)catalysts with high activity and stability at large current density is a major challenge for energy-saving H_(2) production in water electrolysis.Herein,we use the pyridinic-N doping carbon layers coupled with tensile strain of FeNi alloy activated by NiFe_(2)O_(4)(FeNi/NiFe_(2)O_(4)@NC)for efficiently increasing the performance of water and urea oxidation.Due to the tensile strain effect on FeNi/NiFe_(2)O_(4)@NC,it provides a favorable modulation on the electronic properties of the active center,thus enabling amazing OER(η_(100)=196 mV)and UOR(E_(10)=1.32 V)intrinsic activity.Besides,the carbon-coated layers can be used as armor to prevent FeNi alloy from being corroded by the electrolyte for enhancing the OER/UOR stability at large current density,showing high industrial practicability.This work thus provides a simple way to prepare high-efficiency catalyst for activating water and urea oxidation. 展开更多
关键词 Carbon-encapsulated Tensile strain Catalyst Oxygen evolution reaction Urea oxidation reaction
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High-pressure minerals and new lunar mineral changesite-(Y) in Chang’e-5 regolith 被引量:1
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作者 Jing Yang Wei Du 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第2期90-97,共8页
Forty-five years after the Apollo and Luna missions, China’s Chang’e-5 (CE-5) mission collected ∼1.73 kg of new lunar materials from one ofthe youngest basalt units on the Moon. The CE-5 lunar samples provide oppor... Forty-five years after the Apollo and Luna missions, China’s Chang’e-5 (CE-5) mission collected ∼1.73 kg of new lunar materials from one ofthe youngest basalt units on the Moon. The CE-5 lunar samples provide opportunities to address some key scientific questions related to theMoon, including the discovery of high-pressure silica polymorphs (seifertite and stishovite) and a new lunar mineral, changesite-(Y). Seifertitewas found to be coexist with stishovite in a silica fragment from CE-5 lunar regolith. This is the first confirmed seifertite in returned lunarsamples. Seifertite has two space group symmetries (Pnc2 and Pbcn) and formed from an α-cristobalite-like phase during “cold” compressionduring a shock event. The aftershock heating process changes some seifertite to stishovite. Thus, this silica fragment records different stagesof an impact process, and the peak shock pressure is estimated to be ∼11 to 40 GPa, which is much lower than the pressure condition forcoexistence of seifertite and stishovite on the phase diagram. Changesite-(Y), with ideal formula (Ca_(8)Y)◻Fe^(2+)(PO_(4))_(7) (where ◻ denotes avacancy) is the first new lunar mineral to be discovered in CE-5 regolith samples. This newly identified phosphate mineral is in the form ofcolumnar crystals and was found in CE-5 basalt fragments. It contains high concentrations of Y and rare earth elements (REE), reaching upto ∼14 wt. % (Y,REE)2O3. The occurrence of changesite-(Y) marks the late-stage fractional crystallization processes of CE-5 basalts combinedwith silicate liquid immiscibility. These new findings demonstrate the significance of studies on high-pressure minerals in lunar materials andthe special nature of lunar magmatic evolution. 展开更多
关键词 evolution MINERALS BASALT
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Asymmetric Drying and Wetting Trends in Eastern and Western China 被引量:1
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作者 Wen WU Fei JI +1 位作者 Shujuan HU Yongli HE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期221-232,共12页
As an important factor that directly affects agricultural production, the social economy, and policy implementation,observed changes in dry/wet conditions have become a matter of widespread concern. However, previous ... As an important factor that directly affects agricultural production, the social economy, and policy implementation,observed changes in dry/wet conditions have become a matter of widespread concern. However, previous research has mainly focused on the long-term linear changes of dry/wet conditions, while the detection and evolution of the non-linear trends related to dry/wet changes have received less attention. The non-linear trends of the annual aridity index, obtained by the Ensemble Empirical Mode Decomposition(EEMD) method, reveal that changes in dry/wet conditions in China are asymmetric and can be characterized by contrasting features in both time and space in China. Spatially, most areas in western China have experienced transitions from drying to wetting, while opposite changes have occurred in most areas of eastern China. Temporally, the transitions occurred earlier in western China compared to eastern China. Research into the asymmetric spatial characteristics of dry/wet conditions compensates for the inadequacies of previous studies, which focused solely on temporal evolution;at the same time, it remedies the inadequacies of traditional research on linear trends over centennial timescales. Analyzing the non-linear trend also provides for a more comprehensive understanding of the drying/wetting changes in China. 展开更多
关键词 aridity index EEMD dry/wet conditions asymmetric evolution
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