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Source rock characterization of the Dingo Claystone,Barrow Subbasin,Australia:Influence of contamination on geochemical analyses
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作者 Ummi Fayyadhah Binti Haji Talipudin Mohamed Ragab Shalaby 《Energy Geoscience》 2025年第1期167-193,共27页
An integrated study on source rock characterization and hydrocarbon generation potential modeling was conducted for the selected Dingo Claystone,Barrow Sub-basin,Australia.In this study,data were collected solely from... An integrated study on source rock characterization and hydrocarbon generation potential modeling was conducted for the selected Dingo Claystone,Barrow Sub-basin,Australia.In this study,data were collected solely from two wells represented by the Bambra-1 and Bambra-2 wells.The collected data include those from bulk geochemical analyses of cuttings and sidewall cores sampled from the Late Jurassic Dingo Claystone.Geochemical data obtained from Rock-Eval pyrolysis and gas chromatography(GC)of extracted organic matter were integrated for source rock characterization and the construction of burial history and hydrocarbon generation in the Dingo Claystone.To improve the accuracy of thermal maturity estimations,only samples with S2 greater than 1 were considered due to potential issues with peak integration and uncertainties of Tmax determination in samples with lower S2 values.Furthermore,Rock-Eval data from the Bambra wells may be unreliable due to the contamination of cuttings and sidewall core(SWC)samples by drilling mud additives and natural hydrocarbons,which could impact the reliability of the data for determining thermal maturity.This study reveals that the Dingo Claystone Formation has total organic carbon(TOC)contents ranging from 0.66%to 8.31%.A poor to good hydrocarbon generation potential is indicated,with a production yield(PY=S_(1)+S_(2))ranging from 1.37 to 10.44 mg HC/g rock.Hydrogen index values vary between 42 and 226 mg HC/g TOC,confirming that the Dingo Claystone is dominantly kerogen TypeⅢ,with minor contributions from typesⅡ/ⅢandⅣ.Thermal maturity ranges from immature to late mature and is mostly in the oil window.This is indicated by T_(max)values of 398-462℃and vitrinite reflectance(Ro,%)of 0.47-1.99.Some samples show suppressed T_(max)and a higher production index,which is typical for samples affected by drilling fluids during drilling operations.Additionally,gas chromatography(GC)analyses are used to interpret the paleodepositional environment showing mixed input between marine and terrestrial origins of the source rocks.One-dimensional basin modeling for the Bambra-1 and Bambra-2 wells was carried out to evaluate the burial and thermal history of the formation.The transformation ratio suggests that hydrocarbon generation has not reached its peak and is still in an ongoing phase.An indication of hydrocarbon migration can be observed in this formation based on the transformation ratio.The effects of contamination warrant further investigation,as it could significantly impact maturity estimates and data reliability. 展开更多
关键词 Sub-basin Late Jurassic Dingo Claystone Source rock characterization Basin and petroleum system modeling
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Recent advances of metal vacancies in energy and environmental catalysis:Synthesis,characterization,and roles
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作者 Long Sun Shunzheng Zhao +4 位作者 Sirui Gao Ronghui Zhu Yiran Tan Xiaolong Tang Honghong Yi 《Green Energy & Environment》 SCIE EI CAS 2025年第1期84-108,共25页
With the ongoing depletion of fossil fuels,energy and environmental issues have become increasingly critical,necessitating the search for effective solutions.Catalysis,being one of the hallmarks of modern industry,off... With the ongoing depletion of fossil fuels,energy and environmental issues have become increasingly critical,necessitating the search for effective solutions.Catalysis,being one of the hallmarks of modern industry,offers a promising avenue for researchers.However,the question of how to significantly enhance the performance of catalysts has gradually drawn the attention of scholars.Defect engineering,a commonly employed and effective approach to improve catalyst activity,has become a significant research focus in the catalysis field in recent years.Nonmetal vacancies have received extensive attention due to their simple form.Consequently,exploration of metal vacancies has remained stagnant for a considerable period,resulting in a scarcity of comprehensive reviews on this topic.Therefore,based on the latest research findings,this paper summarizes and consolidates the construction strategies for metal vacancies,characterization techniques,and their roles in typical energy and environmental catalytic reactions.Additionally,it outlines potential challenges in the future,aiming to provide valuable references for researchers interested in investigating metal vacancies. 展开更多
关键词 Metal vacancies CATALYSIS Construction strategies characterization techniques ROLES
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Laboratory Diagnosis and Molecular Epidemiological Characterization of the First Imported Case of Lassa Fever in China 被引量:1
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作者 Yuliang Feng Wei Li +11 位作者 Mingfeng Jiang Hongrong Zhong Wei Wu Lyubo Tian Guo Chen Zhenhua Chen Can Luo Rongmei Yuan Xingyu Zhou Jiandong Li Xiaorong Yang Ming Pan 《Biomedical and Environmental Sciences》 2025年第3期279-289,共11页
Objective This study reports the first imported case of Lassa fever(LF)in China.Laboratory detection and molecular epidemiological analysis of the Lassa virus(LASV)from this case offer valuable insights for the preven... Objective This study reports the first imported case of Lassa fever(LF)in China.Laboratory detection and molecular epidemiological analysis of the Lassa virus(LASV)from this case offer valuable insights for the prevention and control of LF.Methods Samples of cerebrospinal fluid(CSF),blood,urine,saliva,and environmental materials were collected from the patient and their close contacts for LASV nucleotide detection.Whole-genome sequencing was performed on positive samples to analyze the genetic characteristics of the virus.Results LASV was detected in the patient’s CSF,blood,and urine,while all samples from close contacts and the environment tested negative.The virus belongs to the lineage IV strain and shares the highest homology with strains from Sierra Leone.The variability in the glycoprotein complex(GPC)among different strains ranged from 3.9%to 15.1%,higher than previously reported for the seven known lineages.Amino acid mutation analysis revealed multiple mutations within the GPC immunogenic epitopes,increasing strain diversity and potentially impacting immune response.Conclusion The case was confirmed through nucleotide detection,with no evidence of secondary transmission or viral spread.The LASV strain identified belongs to lineage IV,with broader GPC variability than previously reported.Mutations in the immune-related sites of GPC may affect immune responses,necessitating heightened vigilance regarding the virus. 展开更多
关键词 Lassa fever The first imported case Laboratory diagnosis Epidemiological characterization
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Synthesis and crystal structure characterization of yttrium imido complex:The reactivity of 2-substituted-1-amino-o-carborane with yttrium dialkyl complex
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作者 GUO Liping 《无机化学学报》 北大核心 2025年第7期1409-1415,共7页
2-substituted-1-amino-o-carboranes 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10)(R=CH_(3),1a;R=Ph,1b)were synthesized and the reactions of these compounds with the yttrium dialkyl complex[Y(L)(CH_(2)SiMe3)_(2)](L=[2-(2,5-Me_(2)C_(... 2-substituted-1-amino-o-carboranes 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10)(R=CH_(3),1a;R=Ph,1b)were synthesized and the reactions of these compounds with the yttrium dialkyl complex[Y(L)(CH_(2)SiMe3)_(2)](L=[2-(2,5-Me_(2)C_(4)H_(2)N)C_(6)H4NC(Ph)=NDipp]-,Dipp=2,6-iPr_(2)C_(6)H_(3))were investigated.The 1H NMR spectroscopy indicate that the reaction of ytrrium dialkyl complex with one equivalent of 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10) produce the mixture of ytrrium alkyl-amido complex[Y(L)(2-R-1-NH-o-C_(2)B_(10)H_(10))(CH_(2)SiMe3)](R=CH_(3),2a;R=Ph,2b)and bis(amido)complex[Y(L)(2-R-1-NH-o-C_(2)B_(10)H_(10))_(2)](R=CH_(3),3a;R=Ph,3b).The yttrium bridging imido complex[Y(L)(2-CH_(3)-1-N-o-C_(2)B_(10)H_(10))]_(2)(4a)was obtained by heating the mixture at 55℃for 12 h.Complex 3a was isolated and characterized by treating the yttrium dialkyl complex with two equivalents of 1a.The structures of complexes 3a and 4a were verified by single-crystal Xray diffraction.CCDC:2424136,3a;2424137,4a. 展开更多
关键词 yttrium imide O-CARBORANE synthesis structure characterization
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Petrography and Geochemical Studies of Granitoids from Iro Lake South-East of Moyen Chari in Chad and Geodynamic Implication
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作者 Leontine Tekoum Djatibeye Barnabe Jean Claude Doumnang Mbaigane 《Open Journal of Geology》 2025年第2期87-108,共22页
Located in Southeastern Chad. The Iro lake offers a great opportunity for the study of Precambrian formations and their Phanerozoic cover. Pluton is a Cal-alkaline granite. Due to its geographical location and geologi... Located in Southeastern Chad. The Iro lake offers a great opportunity for the study of Precambrian formations and their Phanerozoic cover. Pluton is a Cal-alkaline granite. Due to its geographical location and geological features, it holds crucial information for understanding the evolution of the Saharan Meta craton (central Africa), which remains poorly studied. One of the objectives is to map the formations Precambrian age in Southeastern Chad. Based on the petrographic and geochemical results, we identified granitoids of pan-African age (biotite granite, aplite granite and pegmatite granite). This Precambrian basement is covered with sedimentary formations (clays, argillites, lateritic cuirasses, etc.). The mineral assemblage is characteristic of acid rocks. Geochemistry reveals rocks with a high SiO2 range (62% - 77%) giving sub-alkaline to calc-alkaline acid rocks with high k (4.62% to 6.39%). The granitoids are classified as S-type hyperaluminous granites. This classification is supported by the presence of peraluminous minerals (e.g., muscovite) within the Iro granitoids, which also have high (>1%). Geochemical variation within the granites is largely due to extensive crystal fractionation. The Pattern of REEs normalized to the primitive mantle shows a pronounced negative Eu anomaly, reflecting the crystallization process and fractional crystallization of plagioclase in the rock, and a positive Yb anomaly. The role of plagioclase fractionation was relatively major during the earlier intrusive stages (consistent with the presence of Eu anomalies) and slightly increased, together with biotite and K-feldspar fractionation, during the later (granitic) rock crystallization. The Pattern of the spider normalized to MORBs shows two pronounced negative anomalies in TiO2 and Cs and a slight negative anomaly in Ba. The loss of Ba, Ti and Cs may be caused by the plagioclase fractionation, apatite and ilmenite crystal. The Ba anomaly is also controlled by the presence of K-feldspar and mica. The observed Ti anomalies are due to the fractionation of magnetite indicating a subduction environment (or remelting of a source from a subduction environment). 展开更多
关键词 PETROGRAPHY geochemical GRANITOIDS Iro Lake Moyen-Chari CHAD
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Characterization of Clay Raw Materials from Three Kankan Clay Deposits with a View to Their Use as Building Materials
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作者 Thierno Abdoulaye Barry Abdou Mbaye +5 位作者 Insa Badiane Albert Manga Badiane Stéphane Freslon Bérenger Aranda Laurent Molez Magatte Camara 《Journal of Materials Science and Chemical Engineering》 2025年第2期31-52,共22页
Clays are a constituent of the earth. As a result, the discovery and traditional use of clays in construction and pottery worldwide dates back to antiquity. Guinea has several deposits of clay minerals whose chemical ... Clays are a constituent of the earth. As a result, the discovery and traditional use of clays in construction and pottery worldwide dates back to antiquity. Guinea has several deposits of clay minerals whose chemical and mineralogical compositions have been little studied. Despite lacking of scientific data on these clay minerals, they are used today in pottery and habitat construction. As a step towards promoting the use of clay materials in Guinea, we conducted a study of the physicochemical and mineralogical properties of three natural clays from Kakan in the Republic of Guinea (AKKB, AKKE, AKKO) used in habitat construction. The aims of this work were to better understand their properties, but above all to be able to act on them to improve and broaden their applications, which until now have been limited to construction. These clays were studied by X-ray diffraction (XRD), X-ray fluorescence spectrometry (XRF), moisture content (%W), laser granulometry, Atterberg limits, specific surface area, infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis and differential thermal analysis (TGA/DTA). These analyses revealed that the main clay minerals present in our samples are kaolinite, illite and, montmorillonite, with the addition of impurities, the most abundant of which is quartz. 展开更多
关键词 characterization Clay Minerals Kankan Habitat Construction
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Heterologous Expression,Purification and Enzymatic Characterization of Xylitol Dehydrogenase from the Thermophilic Fungus Talaromyces emersonii
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作者 MENG Er QU Cong +8 位作者 YI Ke LI Hui-Min DUAN Xin-Yi ZHANG Zhe-Yuan HE Shao-Long LUO Yu-Tao WU Lei ZHANG Dong-Yi LIU Chang-Jun 《中国生物化学与分子生物学报》 北大核心 2025年第7期1007-1018,共12页
The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose⁃catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monit... The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose⁃catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monitoring xylitol concentration.In this study,the gene encoding the thermophilic fungus Talaromyces emersonii XDH(TeXDH)was heterologously expressed in Escherichia coli BL21(DE3)at 16℃in the soluble form.Recombinant TeXDH with high purity was purified by using a Ni⁃NTA affinity column.Size⁃exclusion chromatography and SDS⁃PAGE analysis demonstrated that the puri⁃fied recombinant TeXDH exists as a native trimer with a molecular mass of approximately 116 kD,and is composed of three identical subunits,each with a molecular weight of around 39 kD.The TeXDH strictly preferred NAD^(+)as a coenzyme to NADP^(+).The optimal temperature and pH of the TeXDH were 40℃and 10.0,respectively.After EDTA treatment,the enzyme activity of TeXDH decreased to 43.26%of the initial enzyme activity,while the divalent metal ions Mg^(2+)or Ca^(2+)could recover the enzyme activity of TeXDH,reaching 103.32%and 110.69%of the initial enzyme activity,respectively,making them the optimal divalent metal ion cofactors for TeXDH enzyme.However,the divalent metal ions of Mn^(2+),Ni^(2+),Cu^(2+),Zn^(2+),Co^(2+),and Cd^(2+)significantly inhibited the activity of TeXDH.ICP⁃MS and molecular doc⁃king studies revealed that 1 mol/L of TeXDH bound 2 mol/L Zn^(2+)ions and 1 mol/L Mg^(2+)ion.Further⁃more,TeXDH exhibited a high specificity for xylitol,laying the foundation for the development of future xylitol biosensors. 展开更多
关键词 xylitol dehydrogenase(XDH) Talaromyces emersonii heterologous expression enzymatic characterization
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In situ synthesis,crystal structure,and magnetic characterization of a trinuclear copper complex based on a multi-substituted imidazo[1,5-a]pyrazine scaffold
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作者 WANG Zhaodong 《无机化学学报》 北大核心 2025年第3期597-604,共8页
A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]py... A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]pyrazine scaffold was serendipitously prepared from the reaction of the pro-ligand of H_(2)L1(N,N'-bis(pyrazin-2-ylmethyl)pyrazine-2,3-dicarboxamide) with CuSO_(4)·5H_(2O) in aqueous solution at room temperature.Complex 1 was characterized by IR,single-crystal X-ray analysis,and magnetic susceptibility measurements.Single-crystal X-ray analysis reveals that the complex consists of three Cu(Ⅱ) ions,two in situ transformed L2~-ligands,two coordinated sulfates,seven coordinated water molecules,and eight uncoordinated water molecules.Magnetic susceptibility measurement indicates that there are obvious ferromagnetic coupling interactions between the adjacent Cu(Ⅱ) ions in 1.CCDC:1852713. 展开更多
关键词 amide ligand copper complex single crystal structure C-N coupling magnetic characterization
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Clinical and Biological Characterization of Type 2 Diabetic Patients Followed at the National Center for Diabetology and Arterial Hypertension of the Central Hospital of Yaoundé, Cameroon
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作者 Etame Honoré Lucien Sone Nyemb Nyunaï +5 位作者 Bibi Thérèse Stella Souga Tsague Ginette Dzefouo Cédric Gueguim Christine Anne Ndzana Nteppe Leonel Mbah Mba Fabrice Medou 《Open Journal of Epidemiology》 2025年第1期19-35,共17页
Introduction: Diabetes remains a real public health problem today, due to its associated morbidity and mortality. It induces numerous metabolic, biochemical, hematological, and immunological changes, responsible for m... Introduction: Diabetes remains a real public health problem today, due to its associated morbidity and mortality. It induces numerous metabolic, biochemical, hematological, and immunological changes, responsible for multiple complications. The objective of this study was to characterize clinically and biologically type 2 diabetic patients followed at the National Center for Diabetology and Arterial Hypertension of the Central Hospital of Yaoundé. Method: This prospective, cross-sectional, and analytical study took place from April 5 to July 31, 2023 (4 months) on 100 diabetic patients of both sexes (61 women and 39 men), aged from 31 to 88 years. Body Mass Index, systolic and diastolic blood pressure, and cardiac frequency were measured on each of the patients. Subsequently, blood was collected from the patients for the determination of the complete blood count, HBA1c, lipid profile, serum albumin, TNF-α, and IL-6 levels. The data were analyzed using SPSS 17.0 software. Results: The age average of our population was 56.99 ± 11.51 years, the population was primarily female (61%) and primarily between the ages of 55 and 88. 67% of respondents were married. 59% went to secondary school. 73% of them lived in urban areas. 30% were obese and 40% were overweight, with an average BMI of 28.75 kg/m2. 76% of patients took oral antidiabetic medications. HbA1c level average was 8.65%, with 60% having readings above 6.5%. Low hemoglobin and hypochromia were among the abnormalities of red blood cells observed. Lipid profiles revealed low HDL-cholesterol and high triglycerides and cholesterol. Elevated levels of TNF-α and IL-6 indicated inflammation and cardiovascular risk. Conclusion: These results indicate the necessity of focused diabetic care and management on diabetic patients attending the central hospital of Yaoundé, Cameroon. 展开更多
关键词 CLINICAL BIOLOGICAL characterization Type 2 Diabetic Patients Central Hospital of Yaoundé
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Sensory Characterizations and Optimization of Cashew Apple Jam Formulations Using Baobab Powder as a Source of Pectin
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作者 Marie Bianoun Louise Dégni Doudjo Soro +3 位作者 Essan Bla Zita N’Goran-Aw Djedjro Clément Akmel Nogbou Emmanuel Assidjo Kouassi Benjamin Yao 《Food and Nutrition Sciences》 2025年第1期120-136,共17页
Cashew processing in Côte d’Ivoire focuses only on the cashew nut, to the detriment of the apple. Only a very small proportion of the apple is processed into juice. The aim of this work is to enhance the value o... Cashew processing in Côte d’Ivoire focuses only on the cashew nut, to the detriment of the apple. Only a very small proportion of the apple is processed into juice. The aim of this work is to enhance the value of cashew apples by transforming them into jam. Specifically, the aim was first to characterize the sensory properties of cashew apple jam formulations using baobab powder as a source of pectin and then to optimise the formulations. A Box-Behken design with pH, Sugar, and Baobab as factors was used to model and characterize the jam sensory descriptors, and a multivariate analysis with SensomineR was used to characterize the jam formulations. The desirability function was used to optimise the formulations. The results show globally significant regressions at the 0.05 threshold for the sensory descriptors Gelling, Brilliance, Smell, Sweetness, and (-)Astringency, with the exception of (-)Salinity. The R2 coefficients are greater than 80%. The factors studied could have effects on the sensory descriptors of cashew jam formulations. The Baobab had the main effect on the gelling, smell, and astringency of the jams. Brilliance depended on the added sugar. A product effect (p < 0.001) was observed for the descriptors Smell, Gelling, Brilliance, and Sweetness, as these allowed the panelists to find differences between the formulations. Optimum jam formulation can be achieved with 51.56% sugar and 2.12% Baobab at a pH of 3.15. Cashew apple jam using Baobab offers opportunities to add value to apples that have long been abandoned in the field. It would be important to find conditions for prolonged storage of this jam. 展开更多
关键词 Cashew Apple Sensory characterization Jam Formulation Area Design Product Effect Overall Desirability
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Progress and Prospect of Cryogenic Micro-and Nanomechanical In-Situ Characterization Techniques Based on Electron Microscopy
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作者 Langlang Feng Keqiang Li Guangjian Peng 《Acta Mechanica Solida Sinica》 2025年第2期229-239,共11页
The advancement of electron microscopy technology has driven the development of electron microscopes that can apply mechanical loading while observing samples,providing a valuable tool for In-Situ mechanical character... The advancement of electron microscopy technology has driven the development of electron microscopes that can apply mechanical loading while observing samples,providing a valuable tool for In-Situ mechanical characterization of materials.In response to the need to characterize the evolution of the mechanical behavior of structural materials,such as aerospace materials,in real cryogenic service environments,and to provide an experimental basis for improving their macroscopic cryogenic mechanical properties,the advancement of In-Situ characterization techniques capable of offering both cryogenic environments and mechanical loading has become imperative.There have been scholars using this technique to carry out cryogenic mechanical In-Situ studies of related materials,with experimental studies dominating in general,and a few reviews of mechanical characterization techniques mentioning cryogenic temperatures.In order to make it easier to conduct research using such characterization techniques and to further promote the development of related characterization techniques,this review compiles the previous work and summarizes the electron microscope-based In-Situ characterization techniques for cryogenic micro-and nanomechanics.These techniques primarily include transmission electron microscopy-based cryogenic tensile and indentation methods,as well as scanning electron microscopy-based cryogenic tensile,indentation,compression,and bending methods.Furthermore,the review outlines the prospective future development of In-Situ characterization techniques for cryogenic micro-and nanomechanics. 展开更多
关键词 Electron microscopy Micro-and nanomechanics Cryomechanical characterization In-Situ characterization
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Experimental Characterization of the Thermal Properties of Thin Polypropylene Plates Reinforced with Residues and Fibers from the Borassus Wood (Rônier) of Chad
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作者 Abakar Malgnan Kimtangar Ngargueudedjim +2 位作者 Bruno Bassa Hinpere Wedjou Bianpambe Guy Edgar Ntamack 《Open Journal of Applied Sciences》 2025年第2期517-529,共13页
This study focuses on the thermophysical characterizations of composite materials made from polypropylene reinforced with residues and fibers from Borassus wood from Chad. These properties are experimentally determine... This study focuses on the thermophysical characterizations of composite materials made from polypropylene reinforced with residues and fibers from Borassus wood from Chad. These properties are experimentally determined at different temperatures using the hot wire method of the “FP2C” machine, where the hot wire probe is inserted between two specimens. The values of the thermal conductivity in powdered Borassus wood range from 0.170 W/mK to 0.182 W/mK for female wood (FNTF) and from 0.169 W/mK to 0.173 W/mK for male wood. For the female and male fibers, the thermal conductivity values range from 0.137 W/mK to 0.157 W/mK for the female and from 0.138 W/mK to 0.168 W/mK for the male. The thermal effusivity of the residues and fibers of Borassus wood varies from: 509.6 Ws1/2/m2K to 543 Ws1/2/m2K for the powder of female wood and from 524.6 Ws1/2/m2K to 547 Ws1/2/m2K for the powder of male wood. For the fibers of Borassus wood, the values range from 410.6 Ws1/2/m2K to 523.6 Ws1/2/m2K for the female wood fibers and from 420.3 Ws1/2/m2K to 480.3 Ws1/2/m2K for the male wood fibers. These results are important for the applications of Borassus wood residues and fibers in construction works regarding the thermal insulation of habitats. 展开更多
关键词 Composite Materials Residues and Fibers of Rônier Wood from Chad Thin Sheets Thermal Properties characterization
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SiO_(2)'-CaO/(CaO+K_(2)O)(S'CK)Diagram as a Petrochemical Tool for Deciphering the Tectono-Magmatic Characterization of Granitoid Suites 被引量:1
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作者 SUN Mingming WANG Yang 《Acta Geologica Sinica(English Edition)》 2025年第2期598-610,共13页
The SiO_(2)'-CaO/(CaO+K_(2)O)(S'CK)diagram is an empirically derived major element-based equivalent to the modal IUGS alkali feldspar-quartz-plagioclase classification scheme for granitoids.It employs the cont... The SiO_(2)'-CaO/(CaO+K_(2)O)(S'CK)diagram is an empirically derived major element-based equivalent to the modal IUGS alkali feldspar-quartz-plagioclase classification scheme for granitoids.It employs the content of SiO_(2)and CaO/(CaO+K_(2)O)ratio to approximate the IUGS classification diagram and a normative-based Q'-ANOR plot.Four trends have been superimposed onto the SiO_(2)'-CaO/(CaO+K_(2)O)diagram based on published datasets from the Peninsular Ranges(calcic:C),Tuolumne(calc-alkalic:CA),Sherman(alkali-calcic:AC),and Bjerkreim-Sokndal(alkalic:A)batholiths,which were employed to constrain the positions of the C-CA,CA-AC and AC-A suite boundaries on the SiO_(2)versus(Na_(2)O+K_(2)O-CaO)(or modified alkali-lime index,MALI)granitic classification diagram.A merit of the SiO_(2)'-CaO/(CaO+K_(2)O)plot is identifying rock types comprising a suite and their relative abundances.The distinguished projections of five typical granitoid assemblages,which are summarized by Bonin et al.(2020),demonstrate the ability of SiO_(2)'-CaO/(CaO+K_(2)O)diagram to decipher their petrogenesis.The SiO_(2)'-CaO/(CaO+K_(2)O)plots for the plutonic suites of'known'tectonic settings can reveal their evolution paths and the lithological statistics.Accordingly,it is suggested that the SiO_(2)'-CaO/(CaO+K_(2)O)plot can distinguish the tectonic environments of plutonic suits by comparing the plutonic suites or batholiths of'unknown'tectonic context to the published datasets from granitoid suites formed within'known'tectonic settings.The modified SiO_(2)'-CaO/(CaO+K_(2)O)diagram links the bulk chemical composition of granitoid suites to the likely source,magmatic evolution,and tectonic setting;thus,it may be a useful tectono-magmatic classification scheme for granitoid suites. 展开更多
关键词 classification of granitoid major-element chemistry SiO_(2)'–CaO/(CaO+K_(2)O)diagram tectono-magmatic character
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Erratum to:Hydrochemical characterization of surface waters in Northen Tehran:Integrating cluster-based techniques with Self-Organizing Maps
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作者 Maryam SALIMI Hamid Reza NASSERY +2 位作者 Meysam VADIATI Prosun BHATTACHARYA Akram RAHBAR 《Journal of Mountain Science》 2025年第9期3527-3527,共1页
The title of the online version of the original article was revised.The title of the original article has been revised to:Hydrochemical characterization of surface waters in Northern Tehran:Integrating cluster-based t... The title of the online version of the original article was revised.The title of the original article has been revised to:Hydrochemical characterization of surface waters in Northern Tehran:Integrating cluster-based techniques with Self-Organizing Maps. 展开更多
关键词 northern tehran cluster based techniques characterization surface waters hydrochemical characterization surface waters self organizing maps
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Comparative Mineralogical and Geochemical Compositions within the Fault Gouge in the Surface Exposures of the Mw7.9 Wenchuan Earthquake Fault and Their Implications for Mass Removal and Fluid-Rock Interactions
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作者 Yangyang Wang Sijia Li +2 位作者 Shiyuan Wang Deyang Shi Weibing Shen 《Journal of Earth Science》 2025年第1期266-274,共9页
Geochemistry of the fault gouge record information on fault behaviors and environmental conditions.We investigated variations in the mineralogical and geochemical compositions of the fault gouge sampled from the margi... Geochemistry of the fault gouge record information on fault behaviors and environmental conditions.We investigated variations in the mineralogical and geochemical compositions of the fault gouge sampled from the margin zone(MZ)to the slip central zone(CZ)of the fault gouge in the Beichuan-Yingxiu surface rupture zone of the Wenchuan Earthquake.Results show that the clay minerals contents increase from the MZ to CZ,and the quartz and plagioclase contents slight decrease.An increasing enrichment in Al_(2)O_(3),Fe_(2)O_(3),and K_(2)O are observed toward the CZ;the decomposition of quartz and plagioclase,as well as the depletion of Si O_(2),Ca O,Na_2O,and P_(2)O_(5)suggest that the alkaline-earth elements are carried away by the fluids.It can be explained that the stronger coseismic actions in the CZ allow more clay minerals to form,decompose quartz and plagioclase,and alter plagioclase to chlorite.The mass loss in the CZ is larger than that in MZ,which is maybe due to the more concentrated stress in the strongly deformed CZ,however other causes will not be excluded. 展开更多
关键词 fault gouge mass transfer fluid-rock interactions geochemical transformation Wenchuan Earthquake
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Recent progress and future directions in nanoglass materials: A deep insight into synthesis, characterization, and application
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作者 Anshuman Mishra Marisa A.Frechero +2 位作者 Arnaud Caron Pravin Kumar Singh Ashutosh Tiwari 《Nanotechnology and Precision Engineering》 2025年第1期132-162,共31页
This review article provides a comprehensive examination of the most recent advances in research on nanoglasses,including the methods used to create these materials,their characteristics,and their diverse range of use... This review article provides a comprehensive examination of the most recent advances in research on nanoglasses,including the methods used to create these materials,their characteristics,and their diverse range of uses.An overview of the current trends in nanoglass research connects them to the Sustainable Development Goals,highlighting the current relevance of this topic.The process of manufacturing nanoglasses is explained in depth,highlighting advanced approaches such as inert gas condensation and severe plastic deformation,among other techniques.The prime focus of this review is on analyzing the various dimensions of nanoglass materials,including their structural dynamics and electrical configurations,and how these features contribute to their exceptional thermal stability and mechanical strength.The magnetic characteristics of nanoglasses are examined,highlighting their potential for driving innovation across multiple industries.The primary emphasis is on the biological usefulness of nanoglasses,specifically examining their bioactivity and interaction with biological components,and emphasizing their growing use in nanoscale biomedical applications.With regard to the practical applications of nanoglasses,there are specific discussions of their contributions to biological evaluation,wound healing,catalysis,and environmental sustainability.There is an emphasis on the durability and resistance of nanoglasses in these contexts.The comprehensive overview of nanoglasses provided in this article highlights their significance as revolutionary materials in fields of science and technology.The potential of nanoglasses to contribute to a future that is more sustainable and health oriented is indicated.The article ends by discussing the future directions for nanoglass research and looks forward to the promising possibilities for further investigation and innovation. 展开更多
关键词 NANOGLASS SYNTHESIS characterization NANOCATALYSIS BIOMEDICINE
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High-pressure research on optoelectronic materials:Insights from in situ characterization methods
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作者 Songhao Guo Yiqiang Zhan Xujie Lü 《Matter and Radiation at Extremes》 2025年第3期10-23,共14页
High-pressure research has emerged as a pivotal approach for advancing our understanding and development of optoelectronic materials,which are vital for a wide range of applications,including photovoltaics,light-emitt... High-pressure research has emerged as a pivotal approach for advancing our understanding and development of optoelectronic materials,which are vital for a wide range of applications,including photovoltaics,light-emitting devices,and photodetectors.This review highlights various in situ characterization methods employed in high-pressure research to investigate the optical,electronic,and structural properties of optoelectronic materials.We explore the advances that have been made in techniques such as X-ray diffraction,absorption spectroscopy,nonlinear optics,photoluminescence spectroscopy,Raman spectroscopy,and photoresponse measurement,emphasizing how these methods have enhanced the elucidation of structural transitions,bandgap modulation,performance optimization,and carrier dynamics engineering.These insights underscore the pivotal role of high-pressure techniques in optimizing and tailoring optoelectronic materials for future applications. 展开更多
关键词 optoelectronic materialswe x ray diffraction nonlinear optics situ characterization methods situ characterization optoelectronic materialswhich absorption spectroscopy optoelectronic materials
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Constraints on tectonic evolution and mantle source region properties of the Mid-Pacific Mountains:geochemical insights and geological significance
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作者 CHEN Kai LI Xiaohu +3 位作者 SUN Jiuda WANG Zhuoyi FAN Minghui LI Xue 《Global Geology》 2025年第3期139-158,共20页
This study selects geochemical data of basalts from different seamounts in the Mid-Pacific Mountains province and conducts analyses of major and trace elements as well as Sr-Nd-Pb isotopes to explore the tectonic evol... This study selects geochemical data of basalts from different seamounts in the Mid-Pacific Mountains province and conducts analyses of major and trace elements as well as Sr-Nd-Pb isotopes to explore the tectonic evolution,petrogenesis,and mantle-source magama characteristics of the Mid-Pacific Mountains.The basalts from the Mid-Pacific Mountains are predominantly alkali basalts,rich in alkalies,and changing in potassium.They exhibit geochemical features of ocean island basalts(OIB),with distinct fractionation between light and heavy rare-earth elements and a pronounced Ce negative anomaly(δ_(Ce)=0.16–1.10,average 0.84),along with enrichment in large ion lithophile elements(LILEs).The Mid-Pacific Mountains are intraplate ocean island basalts formed by mantle plume(hotspot)activity,originating mainly from an enriched mantle magma source region,and most of them have undergone low degree of partial melting and a certain degree of crystalline differentiation,with negligible contamination from oceanic crust materials.The Mid-Pacific Mountains exhibit ratios of^(87)Sr/^(86)Sr(i)(0.702733–0.704313,average 0.703452)and^(143)Nd/^(144)Nd(i)(0.512698–0.512996,average 0.512846)which are close to the HIMU mantle endmember,and ratios of 206Pb/204Pb(18.953–19.803),^(207)Pb/^(204)Pb(15.54–15.62)and^(208)Pb/^(204)Pb(38.813–39.514)which are close to the EMII mantle end-member.Combined with the isotopic geochemical characteristics in the West Pacific Seamounts province,the basalts from the Mid-Pacific Mountains were considered to represent a certain proportion of mixing mantle end-members between the HIMU and EMII,possibly formed by the mixing of the HIMU superplume in the South Pacific hotspot region with the EMII secondary mantle plume in the transition zone during their ascent. 展开更多
关键词 Mid-Pacific Mountains BASALTS geochemical characteristics petrogenesis mantle source region
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Characterization and Management of Sewage Sludge in Abomey- Calavi: Pathways to Sustainable Treatment Solutions
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作者 Nikita Topanou Blaise Agbatchi +2 位作者 GouvidéJean Gbaguidi Fidèle Paul Tchobo Jacques Fatombi 《Journal of Environmental & Earth Sciences》 2025年第6期63-72,共10页
In the Republic of Benin,as in many other West African countries,urban areas have experienced rapid popula-tion growth in recent years.This situation has led to an increasing demand for sanitation facilities,necessita... In the Republic of Benin,as in many other West African countries,urban areas have experienced rapid popula-tion growth in recent years.This situation has led to an increasing demand for sanitation facilities,necessitating regular emptying of these systems.In a bid to reduce health risks and protect the surrounding natural environment,the manage-ment of the by-products from these systems has become a significant concern for decision-makers at various levels.This study aims to characterize fecal sludge at the Abomey-Calavi treatment station and suggest a mixed biological treatment approach.Fifteen sewage sludge samples were collected in 1,500 ml plastic bottles from Adjagbo’s Sewage Treatment Station,operated by SGDS-SA,a Waste Management and Sanitation company.Physico-chemical parameters were de-termined using spectrophotometric analysis.Colonies were enumerated using membrane filtration and inoculation.Cor-relation analysis was performed on sewage sludge samples.The main results indicate an alkaline character(pH>7)and a high organic pollutant load in the fecal sludge,with average concentrations of Chemical Oxygen Demand(COD)and Biochemical Oxygen Demand over 5 days(BOD_(5))at 18,730 mg O_(2).L^(-1)and 6,612 mg O_(2).L^(-1),respectively.The COD/BOD_(5) ratio of 2.83 suggests that the material is partially biodegradable.Furthermore,the nutrients exhibited high con-centrations of nitrates,with an average value of 4,786 mg.L^(-1),while nitrites,ammoniacal nitrogen,and orthophosphates had average concentrations of 22.48 mg.L^(-1),119.74 mg.L^(-1),and 239.0 mg.L^(-1),respectively.This study characterized fe-cal sludge at the Abomey-Calavi treatment station and suggests a mixed biological treatment approach. 展开更多
关键词 characterization Fecal Sludge TREATMENT BENIN
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Characterization of Physico-Chemical Changes of Lignin Obtained under Different Conditions of Enzymatic Hydrolysis on an Industrial Scale
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作者 Maris Lauberts Janis Rizikovs +1 位作者 Matiss Pals Karl Pebo 《Journal of Renewable Materials》 2025年第1期115-126,共12页
Research-based on lignin as a bioproduct has grown due to its high availability,reactivity,physicochemical sta-bility,and abundance of different aromatic units.Lignin consists of various functional groups,which can re... Research-based on lignin as a bioproduct has grown due to its high availability,reactivity,physicochemical sta-bility,and abundance of different aromatic units.Lignin consists of various functional groups,which can react in various chemical reactions and serve as a raw material in various processes to obtain multiple products.These characteristics make lignin suitable for synthesizing products from natural raw materials,replacing fossil ones.Due to a high aromatic variety and complex structural arrangement,lignin isolation and fractionation are still challenging.The aim and novelty of this work was the modification of severity and enzymatic hydrolysis proce-dure on an industrial pre-treatment to improve by-products of birch processing as a raw material for the potential production of different products.Lignin from birch wood enzymatic hydrolysis was obtained and marked accord-ingly:HS(high severity),MS(medium severity),and LS(low severity)lignin.Samples were characterized by ash content,analytical pyrolysis,solubility,and viscosity.HS lignin was characterized by a relatively high carbohy-drate content(16%)and lower lignin content(77%).Meanwhile,LS lignin showed increased lignin content(83%)and reduced carbohydrate content(9%).It can be concluded that the delignification process greatly influ-ences the properties of the obtained lignin.HS lignin resulted in a lower polydispersity index(PDI)and more condensed structure,while LS lignin showed a higher PDI but a lower content of carbohydrates.Therefore,look-ing for a golden middle way is necessary whilefinding the conditions according to the usefield. 展开更多
关键词 LIGNIN characterization ENVIRONMENTAL SUSTAINABLE lignin-based materials
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