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Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile
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作者 XU Jian-Qiang MA Zhao-Peng +2 位作者 CHENG Si LIU Zhi-Cong ZHU Guang-Lai 《原子与分子物理学报》 CAS 北大核心 2025年第4期27-32,共6页
The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this wo... The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this work.The following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution function.The results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient decreases.Additionally,the excess molar volume initially decreases,reaches a minimum,and then increases.The rules of radial distribution functions(RDFs)of characteristic atoms are different.With increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then decreases.This indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently. 展开更多
关键词 Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions
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Anti-microbial principles of selected remedial plants from Southern India 被引量:5
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作者 Tirupathi Rao G Suresh Babu K +3 位作者 J Ujwal Kumar Sujana P A Veerabhadr Raoa Sreedhar AS 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第4期298-305,共8页
Objective:To examine the anti-bacterial activity of leaf extracts of Morus alba L.(Moraceae)and Piper betel L.(Piperaceae),and seed extracts of Bombax ceiba L.(Borabacaceae).Methods:We have partially purified plant ex... Objective:To examine the anti-bacterial activity of leaf extracts of Morus alba L.(Moraceae)and Piper betel L.(Piperaceae),and seed extracts of Bombax ceiba L.(Borabacaceae).Methods:We have partially purified plant extracts by solvent extraction method,and evaluated the effect of individual fractions on bacterial growth using Escherichia coli(E.coli),Pseudomonas aeruginosa(P.aeruginosa) and Staphylococcus aureus(S.aureus) bacterial strains.Results:Compared with Morus and Bombax fractions,Piper fractions showed significant growth inhibition on all the three types of bacteria studied.The EtOAc-hexane fractions of Piper leaves exhibited significant antibacterial activity with minimum inhibitory concentrations(MIC) of 50 μg/mL culture against both gram-positive and gram-negative bacteria.The EtOAc-fractions Ⅰ,Ⅱ,and Ⅳ inhibited bacterial colony formation on soft agar in addition to growth inhibition.A combination treatment of piper fractions with ampicillin resulted in significant growth inhibition in E.coli and P.aeruginosa,and combination with anticancer drug geldanamycin(2 μg/mL) showed selective growth inhibition against P.aeruginosa and S.aureus.Three major compounds,i.e.,eugenol,3-hexene-ol and stigmasterol,were primarily identified from Piper betel leaf extractions.Among the individual compounds,eugenol treatment showed improved growth inhibition compared with stigmasterol and 3-hexene-ol.Conclusions:We are reporting potential anti-bacterial compounds from Piper betel against both gram-positive and gram-negative bacteria either alone or in combination with drug treatment. 展开更多
关键词 PIPER BETEL anti-microbial activity Escherichia coli Pseudomonas AERUGINOSA Staphylococcus aureus MORUS ALBA Bombax ceiba Minimum inhibitory concentration Growth inhibition
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Serological profiling of Crohn’s disease and ulcerative colitis patients reveals anti-microbial antibody signatures 被引量:2
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作者 Mahasish Shome Lusheng Song +8 位作者 Stacy Williams Yunro Chung Vel Murugan Jin G Park William Faubion Shabana F Pasha Jonathan A Leighton Joshua LaBaer Ji Qiu 《World Journal of Gastroenterology》 SCIE CAS 2022年第30期4089-4101,共13页
BACKGROUND The healthcare burden of inflammatory bowel disease(IBD)is rising globally and there are limited non-invasive biomarkers for accurate and early diagnosis.AIM To understand the important role that intestinal... BACKGROUND The healthcare burden of inflammatory bowel disease(IBD)is rising globally and there are limited non-invasive biomarkers for accurate and early diagnosis.AIM To understand the important role that intestinal microbiota play in IBD pathogenesis and identify anti-microbial antibody signatures that benefit clinical management of IBD patients.METHODS We performed serological profiling of 100 Crohn’s disease(CD)patients,100 ulcerative colitis(UC)patients and 100 healthy controls against 1173 bacterial and 397 viral proteins from 50 bacteria and 33 viruses on protein microarrays.The study subjects were randomly divided into discovery(n=150)and validation(n=150)sets.Statistical analysis was performed using R packages.RESULTS Anti-bacterial antibody responses showed greater differential prevalence among the three subject groups than anti-viral antibody responses.We identified novel antibodies against the antigens of Bacteroidetes vulgatus(BVU_0562)and Streptococcus pneumoniae(SP_1992)showing higher prevalence in CD patients relative to healthy controls.We also identified antibodies against the antigen of Streptococcus pyogenes(SPy_2009)showing higher prevalence in healthy controls relative to UC patients.Using these novel antibodies,we built biomarker panels with area under the curve(AUC)of 0.81,0.87,and 0.82 distinguishing CD vs control,UC vs control,and CD vs UC,respectively.Subgroup analysis revealed that penetrating CD behavior,colonic CD location,CD patients with a history of surgery,and extensive UC exhibited highest antibody prevalence among all patients.We demonstrated that autoantibodies and anti-microbial antibodies in CD patients had minimal correlation.CONCLUSION We have identified antibody signatures for CD and UC using a comprehensive analysis of antimicrobial antibody response in IBD.These antibodies and the source microorganisms of their target antigens improve our understanding of the role of specific microorganisms in IBD pathogenesis and,after future validation,should aid early and accurate diagnosis of IBD. 展开更多
关键词 Inflammatory bowel disease anti-microbial antibody Protein microarray Crohn’s disease Ulcerative colitis Gut microbiome
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Anti-inflammation Activities of Essential Oil and Anti-microbial Activities Of Ethanol Extraction from China's Rosemary 被引量:1
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作者 Jingbo ZHOU Ruqiang HUANG +1 位作者 Jihong HUANG Junwei FENG 《Agricultural Science & Technology》 CAS 2015年第5期1034-1037,1047,共5页
Rosemary(Rosmarius officinalis L.), an endemic plant species in south region of China, is traditionally used as a spice. In this research, the anti-inflammatory activities of essential oil and the antibacterial activi... Rosemary(Rosmarius officinalis L.), an endemic plant species in south region of China, is traditionally used as a spice. In this research, the anti-inflammatory activities of essential oil and the antibacterial activities of ethanol extraction were determined, respectively. Results showed that based on the GC-MS analysis there were 35 kinds of active ingredients in the essential oil in totally, mainly including D-limonene(24.158 ml/L), α-Pinene(23.325 ml/L), Camphor(9.855 ml/L),Camphene(7.076 ml/L), Verbenone(6.685 ml/L), Borneol(5.580 ml/L), etc. The LCUV determination indicated that the main components in the ethanol extractionwere rosmarinic acid(3 910 mg/kg) and carnosic acid(2 970 mg/kg). By mice peritoneal macrophage phagocytosis of chicken erythrocytes experiment, the essential oil of rosemary was shown having a significant role in anti-inflammation. And the ethanol extraction had broad-spectrum antibacterial effects, but had no effect on mold by the agar diffusion method of 8 bacteria. As a result, both rosemary essential oil and ethanol extraction had good potential medicinal values. 展开更多
关键词 China's rosemary Essential oil EXTRACTION Anti-inflammation activity anti-microbial activity
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Comparison study of anti-microbial activity between crude extract of Kappaphycus alvarezii and Andrographis paniculata
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作者 Xin Qi Chuah Wenlynn Mun Swee Sen Teo 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2017年第8期729-731,共3页
To evaluate the antimicrobial properties of Kappaphycus alvarezii (K. alvarezii) and Andrographis paniculata (A. paniculata) and to compare the microbial inhibition activities between these two crude extract... To evaluate the antimicrobial properties of Kappaphycus alvarezii (K. alvarezii) and Andrographis paniculata (A. paniculata) and to compare the microbial inhibition activities between these two crude extracts.MethodsBoth K. alvarezii and A. paniculata were extracted with methanol before the commencement of antimicrobial properties studies. There were a total of eight species of bacteria, including Gram-positive bacteria Bacillus cereus, Bacillus subtilis, Staphylococcus aureus and Staphylococcus epidermidis and Gram-negative bacteria, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Salmonella enterica. The antimicrobial activity was tested by disk diffusion method.ResultsCrude extract of K. alvarezii was found not effective against both Gram-positive and Gram-negative bacteria. In contrast, A. paniculata showed higher inhibition towards the growth of Gram-positive bacteria compared to Gram-negative bacteria. Results revealed that Bacillus subtilis was susceptible at lower concentration of A. paniculata crude extract however Staphylococcus epidermidis was the most susceptible towards A. paniculata at higher concentration. Although the inhibition zones produced by the crude extract were smaller than that of the positive control, streptomycin disc, A. paniculata crude extract still can be considered as potential antimicrobial agents either because it is a natural product or the active compound which is yet identified from its crude extract.ConclusionsCrude extract of K. alvarezii has zero inhibition in bacteria growth whereas A. paniculata exerted higher inhibition towards Gram-positive bacteria. The bioactive compounds contained by A. paniculata can be evaluated in order to yield a better vision towards the mode of action. 展开更多
关键词 Kappaphycus alvarezii Andrographis paniculata anti-microbial GRAM-POSITIVE GRAM-NEGATIVE
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Properties and Characteristics of Regolith-Based Materials for Extraterrestrial Construction 被引量:1
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作者 Cheng Zhou Yuyue Gao +4 位作者 Yan Zhou Wei She Yusheng Shi Lieyun Ding Changwen Miao 《Engineering》 SCIE EI CAS CSCD 2024年第6期159-181,共23页
The construction of extraterrestrial bases has become a new goal in the active exploration of deep space.Among the construction techniques,in situ resource-based construction is one of the most promising because of it... The construction of extraterrestrial bases has become a new goal in the active exploration of deep space.Among the construction techniques,in situ resource-based construction is one of the most promising because of its good sustainability and acceptable economic cost,triggering the development of various types of extraterrestrial construction materials.A comprehensive survey and comparison of materials from the perspective of performance was conducted to provide suggestions for material selection and optimization.Thirteen types of typical construction materials are discussed in terms of their reliability and applicability in extreme extraterrestrial environment.Mechanical,thermal and optical,and radiation-shielding properties are considered.The influencing factors and optimization methods for these properties are analyzed.From the perspective of material properties,the existing challenges lie in the comprehensive,long-term,and real characterization of regolith-based construction materials.Correspondingly,the suggested future directions include the application of high-throughput characterization methods,accelerated durability tests,and conducting extraterrestrial experiments. 展开更多
关键词 Extraterrestrial construction Characterization Mechanical property Thermal property Optical property Radiation-shielding
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Physical,mechanical and thermal properties of vacuum sintered HUST-1 lunar regolith simulant 被引量:1
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作者 Wenbin Han Yan Zhou +2 位作者 Lixiong Cai Cheng Zhou Lieyun Ding 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1243-1257,共15页
Establishing a base on the Moon is one of the new goals of human lunar exploration in recent years.Sintered lunar regolith is one of the most potential building materials for lunar bases.The physical,mechanical and th... Establishing a base on the Moon is one of the new goals of human lunar exploration in recent years.Sintered lunar regolith is one of the most potential building materials for lunar bases.The physical,mechanical and thermal properties of sintered lunar regolith are vital performance indices for the structural design of a lunar base and analysis of many critical mechanical and thermal issues.In this study,the HUST-1 lunar regolith simulant(HLRS)was sintered at 1030,1040,1050,1060,1070,and 1080℃.The effect of sintering temperature on the compressive strength was investigated,and the exact value of the optimum vacuum sintering temperature was determined between 1040 and 1060℃.Then,the microstructure and material composition of vacuum sintered HLRS at different temperatures were characterized.It was found that the sintering temperature has no significant effect on the mineral composition in the temperature range of 1030-1080℃.Besides,the heat capacity,thermal conductivity,and coefficient of thermal expansion(CTE)of vacuum sintered HLRS at different temperatures were investigated.Specific heat capacity of sintered samples increases with the increase of test temperature within the temperature range from-75 to 145℃.Besides,the thermal conductivity of the sintered sample is proportional to density.Finally,the two temperatures of 1040 and 1050℃were selected for a more detailed study of mechanical properties.The results showed that compressive strength of sintered sample is much higher than tensile strength.This study reveals the effects of sintering temperature on the physical,mechanical and thermal properties of vacuum sintered HLRS,and these material parameters will provide support for the construction of future lunar bases. 展开更多
关键词 Lunar base Lunar regolith simulant Vacuum sintering Physical properties Mechanical properties Thermal properties
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Synthesis,Crystal Structure and Evaluations of Its Cytotoxicity,Anti-microbial and Anti-hydroxyl Radical Activities of a New Co-crystal Compound(C6H6Cl2N2O2S)·(Phen)·H2O
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作者 黄岚珍 王雅楠 +1 位作者 蔡卓 秦秀英 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第7期1078-1086,共9页
Co-crystal is a very potential kind of drug solid forms, and has a far-reaching influence on designing and preparing drugs. A new 1:1:1 co-crystal compound consisting of 4-amino-3,5-dichloro-benzenesulfonamide, 1,10... Co-crystal is a very potential kind of drug solid forms, and has a far-reaching influence on designing and preparing drugs. A new 1:1:1 co-crystal compound consisting of 4-amino-3,5-dichloro-benzenesulfonamide, 1,10-phenanthroline and water was synthesized, and its crystal structure was characterized by X-ray diffraction method. The compositions of the co-crystal are self-assembled into a three-dimensional network structure via intermolecular interactions including hydrogen bonds, π-π stacking, Cl???Cl interactions and van der Waals' forces. According to the evaluations of cytotoxicity assays, anti-microbial and anti-hydroxyl radicals, this co-crystal is a potential drug. 展开更多
关键词 4-amino-3 5-dichloro-benzenesulfonamide CO-CRYSTAL CYTOTOXICITY anti-microbial anti-hydroxyl radical
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Preparation and Activity of a Nanometer Anti-microbial Polyurethane
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作者 关燕清 彭长连 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第4期540-545,共6页
A novel way for photo-immobilization with interferon- α(IFN- α) on the surface of polyurethane (PU) material, which makes PU condom more effective function in the future, was investigated. A kind of photoactive ... A novel way for photo-immobilization with interferon- α(IFN- α) on the surface of polyurethane (PU) material, which makes PU condom more effective function in the future, was investigated. A kind of photoactive arylazide-4-azidobenzoic acid was modified to IFN- α with the confirmation of IR and Raman spectrum. Micro morphology of the photo-immobilized cell factors was observed by FESEM as well as CSLM at the level of nanometer. Finally, the product with elementary test of anti-microbial was also evaluated. 展开更多
关键词 polyurethane (PU) interferon-α (IFN- α) photo-immobilization anti-microbial
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Phytochemicals Screening, Phenolic Estimation and Evaluation for Anti-Oxidant, Anti-Inflammatory and Anti-Microbial Activities of Sequentially Soxhlet Extracted Coconut Testa
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作者 Sashi Bhusan Ojha Shaktirekha Roy +1 位作者 Soumya Das Gunanidhi Dhangadamajhi 《Food and Nutrition Sciences》 2019年第8期900-922,共23页
Background: In many coconut industries, the outer layer of thin brown skin of coconut kernel known as testa is peeled out as a byproduct. Despite the testa is rich in fat and plenty of polyphenolic compounds, it has b... Background: In many coconut industries, the outer layer of thin brown skin of coconut kernel known as testa is peeled out as a byproduct. Despite the testa is rich in fat and plenty of polyphenolic compounds, it has been underutilized either as animal feed, serving as raw materials for bio-diesel production or discarded directly. Anticipating coconut testa (CT) as a natural source of multiple phyto-chemicals, its exploitation for the pharmacological activity or utilization as value added product is required which may reduce the disposal costs as well. Methods: Secondary metabolites from CT were extracted sequentially with different organic solvents based on polarity in the soxhlet apparatus followed by extraction with sterilized water. The crude dried extracts thus prepared were evaluated for qualitative screening of phytochemicals and quantitative estimation of total phenols, flavonoids and tannin content. Moreover, the antioxidant, anti-inflammatory and anti-microbial activities were also investigated. Results: Phytochemicals screening revealed the presence of polyphenolic compounds in methanolic fraction including phenols (822.60 ± 16.36 mg/g), flavonoids (103.30 ± 9.78 mg/g) and tannin (663.50 ± 19.26 mg/g), whereas non-phenolic compounds were present in other fractions. While methanolic fraction showed invariably the highest anti-oxidant activity in multiple assay methods, non-phenolic compounds in aqueous and chloroform fractions exhibited high anti-inflammatory activity. Antimicrobial activity was observed by both phenolic and non-phenolic compounds. Conclusion: The findings of the study reveal that CT is a rich source of various polyphenolic and non-phenolic natural antioxidants, anti-inflammatory and antimicrobial compounds. These findings are promising and form the basis to identify the number of active components and their characterization. 展开更多
关键词 COCONUT TESTA PHYTOCHEMICALS ANTI-OXIDANT Anti-Inflammatory anti-microbial SOXHLET Extraction
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High-throughput calculations combining machine learning to investigate the corrosion properties of binary Mg alloys 被引量:3
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作者 Yaowei Wang Tian Xie +4 位作者 Qingli Tang Mingxu Wang Tao Ying Hong Zhu Xiaoqin Zeng 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1406-1418,共13页
Magnesium(Mg)alloys have shown great prospects as both structural and biomedical materials,while poor corrosion resistance limits their further application.In this work,to avoid the time-consuming and laborious experi... Magnesium(Mg)alloys have shown great prospects as both structural and biomedical materials,while poor corrosion resistance limits their further application.In this work,to avoid the time-consuming and laborious experiment trial,a high-throughput computational strategy based on first-principles calculations is designed for screening corrosion-resistant binary Mg alloy with intermetallics,from both the thermodynamic and kinetic perspectives.The stable binary Mg intermetallics with low equilibrium potential difference with respect to the Mg matrix are firstly identified.Then,the hydrogen adsorption energies on the surfaces of these Mg intermetallics are calculated,and the corrosion exchange current density is further calculated by a hydrogen evolution reaction(HER)kinetic model.Several intermetallics,e.g.Y_(3)Mg,Y_(2)Mg and La_(5)Mg,are identified to be promising intermetallics which might effectively hinder the cathodic HER.Furthermore,machine learning(ML)models are developed to predict Mg intermetallics with proper hydrogen adsorption energy employing work function(W_(f))and weighted first ionization energy(WFIE).The generalization of the ML models is tested on five new binary Mg intermetallics with the average root mean square error(RMSE)of 0.11 eV.This study not only predicts some promising binary Mg intermetallics which may suppress the galvanic corrosion,but also provides a high-throughput screening strategy and ML models for the design of corrosion-resistant alloy,which can be extended to ternary Mg alloys or other alloy systems. 展开更多
关键词 Mg intermetallics Corrosion property HIGH-THROUGHPUT Density functional theory Machine learning
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Effects of deformation temperatures on microstructures,aging behaviors and mechanical properties of Mg-Gd-Er-Zr alloys fabricated by hard-plate rolling 被引量:2
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作者 Ke Liu Dalong Hu +4 位作者 Feng Lou Zijian Yu Shubo Li Xian Du Wenbo Du 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第6期2345-2359,共15页
In this investigation,a high-strength Mg-12Gd-1.0Er-0.5Zr(wt.%)alloy sheet was produced by hot extrusion(HE)and subsequent hard-plate rolling(HPR)at different temperatures.The results indicate that the microstructures... In this investigation,a high-strength Mg-12Gd-1.0Er-0.5Zr(wt.%)alloy sheet was produced by hot extrusion(HE)and subsequent hard-plate rolling(HPR)at different temperatures.The results indicate that the microstructures of these final-rolled sheets are inhomogeneous,mainly including coarse deformed grains and dynamic recrystallized(DRXed)grains,and the volume fraction of these coarse deformed grains increases as the rolling temperature increases.Thus,more DRXed grains can be found in R-385℃sheet,resulting in a smaller average grain size and weaker basal texture,while the biggest grains and the highest strong basal texture are present in R-450℃sheet.Amounts of dynamic precipitation ofβphases which are mainly determined by the rolling temperature are present in these sheets,and its precipitation can consume the content of Gd solutes in the matrix.As a result,the lowest number density ofβphase in R-450℃sheet is beneficial to modify the age hardening response.Thus,the R-450℃sheet displays the best age hardening response because of a severe traditional precipitation ofβ’(more)andβH/βM(less)precipitates,resulting in a sharp improvement in strength,i.e.ultimate tensile strength(UTS)of∼518±17 MPa and yield strength(YS)of∼438±18 MPa.However,the elongation(EL)of this sheet reduces greatly,and its value is∼2.7±0.3%.By contrasting,the EL of the peak-aging R-385℃sheet keeps better,changing from∼4.9±1.2%to∼4.8±1.4%due to a novel dislocation-induced chain-like precipitate which is helpful to keep good balance between strength and ductility. 展开更多
关键词 Mg-Gd-Er-Zr sheets Age hardening response PRECIPITATES Mechanical properties
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Machine learning applications on lunar meteorite minerals:From classification to mechanical properties prediction 被引量:1
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作者 Eloy Peña-Asensio Josep M.Trigo-Rodríguez +2 位作者 Jordi Sort Jordi Ibáñez-Insa Albert Rimola 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1283-1292,共10页
Amid the scarcity of lunar meteorites and the imperative to preserve their scientific value,nondestructive testing methods are essential.This translates into the application of microscale rock mechanics experiments an... Amid the scarcity of lunar meteorites and the imperative to preserve their scientific value,nondestructive testing methods are essential.This translates into the application of microscale rock mechanics experiments and scanning electron microscopy for surface composition analysis.This study explores the application of Machine Learning algorithms in predicting the mineralogical and mechanical properties of DHOFAR 1084,JAH 838,and NWA 11444 lunar meteorites based solely on their atomic percentage compositions.Leveraging a prior-data fitted network model,we achieved near-perfect classification scores for meteorites,mineral groups,and individual minerals.The regressor models,notably the KNeighbor model,provided an outstanding estimate of the mechanical properties—previously measured by nanoindentation tests—such as hardness,reduced Young’s modulus,and elastic recovery.Further considerations on the nature and physical properties of the minerals forming these meteorites,including porosity,crystal orientation,or shock degree,are essential for refining predictions.Our findings underscore the potential of Machine Learning in enhancing mineral identification and mechanical property estimation in lunar exploration,which pave the way for new advancements and quick assessments in extraterrestrial mineral mining,processing,and research. 展开更多
关键词 METEORITES MOON MINERALOGY Machine learning Mechanical properties
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Microstructures,corrosion behavior and mechanical properties of as-cast Mg-6Zn-2X(Fe/Cu/Ni)alloys for plugging tool applications 被引量:1
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作者 Baosheng Liu Jiali Wei +4 位作者 Shaohua Zhang Yuezhong Zhang Pengpeng Wu Daqing Fang Guorui Ma 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期697-711,共15页
Mg-6Zn-2X(Fe/Cu/Ni)alloys were prepared through semi-continuous casting,with the aim of identifying a degradable magnesium(Mg)alloy suitable for use in fracturing balls.A comparative analysis was conducted to assess t... Mg-6Zn-2X(Fe/Cu/Ni)alloys were prepared through semi-continuous casting,with the aim of identifying a degradable magnesium(Mg)alloy suitable for use in fracturing balls.A comparative analysis was conducted to assess the impacts of adding Cu and Ni,which result in finer grains and the formation of galvanic corrosion sites.Scanner electronic microscopy examination revealed that precipitated phases concentrated at grain boundaries,forming a semi-continuous network structure that facilitated corrosion penetration in Mg-6Zn-2Cu and Mg-6Zn-2Ni alloys.Pitting corrosion was observed in Mg-6Zn-2Fe,while galvanic corrosion was identified as the primary mechanism in Mg-6Zn-2Cu and Mg-6Zn-2Ni alloys.Among the tests,the Mg-6Zn-2Ni alloy exhibited the highest corrosion rate(approximately 932.9 mm/a)due to its significant potential difference.Mechanical testing showed that Mg-6Zn-2Ni alloy possessed suitable ultimate compressive strength,making it a potential candidate material for degradable fracturing balls,effectively addressing the challenges of balancing strength and degradation rate in fracturing applications. 展开更多
关键词 magnesium alloys microstructure micro-galvanic corrosion mechanical properties
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Separation of Amino Acids Based on Thin-Layer Chromatography by a Novel Quinazoline Based Anti-Microbial Agent
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作者 Supriti Sen Sandipan Sarkar +1 位作者 Pijush Kundu Subrata Laskar 《American Journal of Analytical Chemistry》 2012年第9期669-674,共6页
A newly designed quinazoline based compound, 6-pyridin-2-yl-5,6-dihydro-benzo[4,5]imidazo[1,2-c] quinazoline (PDBIQ) has shown the ability for the easy detection of nineteen amino acids on thin-layer chromatography pl... A newly designed quinazoline based compound, 6-pyridin-2-yl-5,6-dihydro-benzo[4,5]imidazo[1,2-c] quinazoline (PDBIQ) has shown the ability for the easy detection of nineteen amino acids on thin-layer chromatography plates as a spray reagent. This new reagent enabled to produce various distinguishable colors with amino acids with different RF values. The detection limits and the binding ability of PDBIQ with amino acids have been calculated. PDBIQ is also able to detect aminoacids from hydrolised seed protein. The title compound also exhibited profound inhibitory action against some gm (+ve) and gm (-ve) bacterial organisms. This paper deals with synthesis, spectroscopic application and biological evaluation of the organic moity. 展开更多
关键词 THIN-LAYER Chromatography Amino Acid NINHYDRIN Binding Constant ANTIMICROBIAL property
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Pulsed current-assisted twelve-roll precision rolling deformation of SUS304 ultra-thin strips with exceptional mechanical properties 被引量:1
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作者 Wanwan Fan Tao Wang +3 位作者 Jinxiong Hou Zhongkai Ren Qingxue Huang Guanghui Wu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第4期291-305,共15页
Innovative pulsed current-assisted multi-pass rolling tests were conducted on a 12-roll mill during the rolling deformation processing of SUS304 ultra-thin strips.The results show that in the first rolling pass,the ro... Innovative pulsed current-assisted multi-pass rolling tests were conducted on a 12-roll mill during the rolling deformation processing of SUS304 ultra-thin strips.The results show that in the first rolling pass,the rolling reduction rate of a conventionally rolled sample(at room temperature)is 33.8%,which can be increased to 41.5%by pulsed current-assisted rolling,enabling the formation of an ultra-thin strip with a size of 67.3μm in only one rolling pass.After three passes of pulsed current-assisted rolling,the thickness of the ultra-thin strip can be further reduced to 51.7μm.To clearly compare the effects of a pulsed current on the microstructure and mechanical response of the ultra-thin strip,ultra-thin strips with nearly the same thickness reduction were analyzed.It was found that pulsed current can reduce the degree of work-hardening of the rolled samples by promoting dislocation detachment,reducing the density of stacking faults,inhibiting martensitic phase transformation,and shortening the total length of grain boundaries.As a result,the ductility of ultra-thin strips can be effectively restored to approximately 16.3%while maintaining a high tensile strength of 1118 MPa.Therefore,pulsed current-assisted rolling deformation shows great potential for the formation of ultra-thin strips with a combination of high strength and ductility. 展开更多
关键词 pulsedcurrent-assisted SUS304 ultra-thinstrip rolling reductionrate WORK-HARDENING mechanical properties
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Spark Plasma Sintering of Mg-based Alloys:Microstructure,Mechanical Properties,Corrosion Behavior,and Tribological Performance 被引量:1
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作者 Alessandro M.Ralls Mohammadreza Daroonparvar Pradeep L.Menezes 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期405-442,共38页
Within the past ten years,spark plasma sintering(SPS)has become an increasingly popular process for Mg manufacturing.In the SPS process,interparticle diffusion of compressed particles is rapidly achieved due to the co... Within the past ten years,spark plasma sintering(SPS)has become an increasingly popular process for Mg manufacturing.In the SPS process,interparticle diffusion of compressed particles is rapidly achieved due to the concept of Joule heating.Compared to traditional and additive manufacturing(AM)techniques,SPS gives unique control of the structural and microstructural features of Mg components.By doing so,their mechanical,tribological,and corrosion properties can be tailored.Although great advancements in this field have been made,these pieces of knowledge are scattered and have not been contextualized into a single work.The motivation of this work is to address this scientific gap and to provide a groundwork for understanding the basics of SPS manufacturing for Mg.To do so,the existing body of SPS Mg literature was first surveyed,with a focus on their structural formation and degradation mechanisms.It was found that successful Mg SPS fabrication highly depended on the processing temperature,particle size,and particle crystallinity.The addition of metal and ceramic composites also affected their microstructural features due to the Zener pinning effect.In degradative environments,their performance depends on their structural features and whether they have secondary phased composites.In industrial applications,SPS'd Mg was found to have great potential in biomedical,hydrogen storage,battery,automotive,and recycling sectors.The prospects to advance the field include using Mg as a doping agent for crystallite size refinement and using bulk metallic Mg-based glass powders for amorphous SPS components.Despite these findings,the interactions of multi-composites on the processing-structure-property relationships of SPS Mg is not well understood.In total,this work will provide a useful direction in the SPS field and serve as a milestone for future Mg-based SPS manufacturing. 展开更多
关键词 Spark plasma sintering Magnesium alloys NANOCRYSTALLINE TRIBOLOGY Mechanical properties Corrosion
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Hydrothermal treatment of pearl millet grains:Effects on nutritional composition,antinutrients and flour properties 被引量:1
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作者 P.Prashanth T.Jayasree Joshi +1 位作者 Shagolshem Mukta Singh P.Srinivasa Rao 《Grain & Oil Science and Technology》 CAS 2024年第2期87-95,共9页
Pearl millet(Pennisetum glaucum)is one of the major millets with high nutritional properties.This crop exhibits exceptional resilience to drought and high temperatures.However,the processing of pearl millet poses a si... Pearl millet(Pennisetum glaucum)is one of the major millets with high nutritional properties.This crop exhibits exceptional resilience to drought and high temperatures.However,the processing of pearl millet poses a significant challenge due to its high lipid content,enzyme activity,and presence of antinutrients.Consequently,it becomes imperative to enhance the quality and prolong the shelf life of pearl millet flour by employing suitable technologies.Hydrothermal treatment in the food industry has long been seen as promising due to its potential to reduce microbial load,inactivate enzymes,and improve nutrient retention.This study aims to investigate the effects of hydrothermal treatment on the quality characteristics of pearl millet.The independent variables of the study were soaking temperature(35,45,55℃),soaking time(2,3,4 h),and steaming time(5,10,15 min).Treatment conditions had a statistically significant effect on nutrient retention.Major antinutrients like tannins and phytates were reduced by 0.99% to 5.94% and 0.36% to 6.00%,respectively,after the treatment.Lipase activity decreased significantly up to 10% with the treatment conditions.The findings of this study could potentially encourage the use of pearl millet flour in the production of various food items and promote the application of hydrothermal treatment in the field of food processing. 展开更多
关键词 Pearl millet Hydrothermal treatment Nutritional properties ANTINUTRIENTS
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Transformation of long-period stacking ordered structures in Mg-Gd-Y-Zn alloys upon synergistic characterization of first-principles calculation and experiment and its effects on mechanical properties 被引量:1
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作者 Mingyu Li Guangzong Zhang +4 位作者 Siqi Yin Changfeng Wang Ying Fu Chenyang Gu Renguo Guan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第5期1867-1879,共13页
Based on experiments and first-principles calculations,the microstructures and mechanical properties of as-cast and solution treated Mg-10Gd-4Y-xZn-0.6Zr(x=0,1,2,wt.%)alloys are investigated.The transformation process... Based on experiments and first-principles calculations,the microstructures and mechanical properties of as-cast and solution treated Mg-10Gd-4Y-xZn-0.6Zr(x=0,1,2,wt.%)alloys are investigated.The transformation process of long-period stacking ordered(LPSO)structure during solidification and heat treatment and its effect on the mechanical properties of experimental alloys are discussed.Results reveal that the stacking faults and 18R LPSO phases appear in the as-cast Mg-10Gd-4Y-1Zn-0.6Zr and Mg-10Gd-4Y-2Zn-0.6Zr alloys,respectively.After solution treatment,the stacking faults and 18R LPSO phase transform into 14H LPSO phase.The Enthalpies of formation and reaction energy of 14H and 18R LPSO are calculated based on first-principles.Results show that the alloying ability of 18R is stronger than that of 14H.The reaction energies show that the 14H LPSO phase is more stable than the 18R LPSO.The elastic properties of the 14H and 18R LPSO phases are also evaluated by first-principles calculations,and the results are in good agreement with the experimental results.The precipitation of LPSO phase improves the tensile strength,yield strength and elongation of the alloy.After solution treatment,the Mg-10Gd-4Y-2Zn-0.6Zr alloy has the best mechanical properties,and its ultimate tensile strength and yield strength are 278.7 MPa and 196.4 MPa,respectively.The elongation of Mg-10Gd-4Y-2Zn-0.6Zr reaches 15.1,which is higher than that of Mg-10Gd-4Y0.6Zr alloy.The improving mechanism of elastic modulus by the LPSO phases and the influence on the alloy mechanical properties are also analyzed. 展开更多
关键词 Mg-Gd-Y-Zn alloys Long-period stacking ordered First-principles calculations ENTHALPIES Mechanical properties
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Effect of sodium starch octenyl succinate-based Pickering emulsion on the physicochemical properties of hairtail myofibrillar protein gel subjected to multiple freeze-thaw cycles 被引量:1
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作者 Huinan Wang Jiaxin Zhang +3 位作者 Xinran Liu Jinxiang Wang Xuepeng Li Jianrong Li 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期1018-1028,共11页
A Pickering emulsion based on sodium starch octenyl succinate(SSOS)was prepared and its effects on the physicochemical properties of hairtail myofibrillar protein gels(MPGs)subjected to multiple freeze-thaw(F-T)cycles... A Pickering emulsion based on sodium starch octenyl succinate(SSOS)was prepared and its effects on the physicochemical properties of hairtail myofibrillar protein gels(MPGs)subjected to multiple freeze-thaw(F-T)cycles were investigated.The whiteness,water-holding capacity,storage modulus(G')and texture properties of the MPGs were significantly improved by adding 1%-2%Pickering emulsion(P<0.05).Meanwhile,Raman spectral analysis demonstrated that Pickering emulsion promoted the transformation of secondary structure,enhanced hydrogen bonds and hydrophobic interactions,and promoted the transition of disulfide bond conformation from g-g-g to g-g-t and t-g-t.At an emulsion concentration of 2%,theα-helix content decreased by 10.37%,while theβ-sheet content increased by 7.94%,compared to the control.After F-T cycles,the structure of the MPGs was destroyed,with an increase in hardness and a decrease in whiteness and water-holding capacity,however,the quality degradation of MPGs was reduced with 1%-2%Pickering emulsion.These findings demonstrated that SSOS-Pickering emulsions,as potential fat substitutes,can enhance the gel properties and the F-T stability of MPGs. 展开更多
关键词 Pickering emulsion Myofibrillar protein Gel properties Freeze-thaw stability Intermolecular interactions
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