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Journal of Materials Science & technology 2013年第5期29卷 419-422页

作者： p.jayaram t.p.jaya Smagul Zh.Karazhanov p.p.pradyumnan Department of physics University of CalicutCalicut University(P.O.)Malappuram DistrictKerala 673 635India Department for Solar Energy Institute for Energy TechnologyInstituttveien 182027 KjellerNorway

the increasing demand in the diverse device applications of transparent conducting oxides （tCOs） requires synthesis of new tCOs of n- or p-type conductivity. this article is about materials engineering of ZnO-SnO2- In2O3-Ga2O3 to synthesize powders of the quaternary compound Zn2-xSn1-xlnxGaxO4-δ in the stoichiometry of x = 0.2, 0.3, and 0.4 by solid state reaction at 1275℃. Lattice parameters were determined by X-ray diffraction （XRD） technique and solubility of In3＋ and Ga3＋ in spinel Zn2SnO4 was found at 1275℃. the solubility limit of In3＋ and Ga3＋ in Zn2SnO4 is found at below x = 0.4. the optical transmittance approximated by the UV-Vis reflectance spectra showed excellent characteristics while optical band gap was consistent across 3.2 eV with slight decrease along increasing x value. Carrier mobility of the species was considerably higher than the older versions of zinc stannate spinel co-substitutions whereas the carrier concentrations were moderate.

关键词： transparent conducting oxides (tCOs) Structural studies Mobility Optical properties

Cutting edge preparation of microdrills by shear thickening polishing for improved hole quality in electronic pCBs

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Frontiers of Mechanical Engineering 2024年第2期19卷 99-107页

作者： Jiahuan WANG Mingfeng KE Jiepei LIAO Yu ZHOU Saurav GOEL jaya VERMA Xu WANG Weigang GUO Julong YUAN Binghai LYU College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310000China Ultra-precision Machining Center Key Laboratory of Special Purpose Equipment and Advanced Manufacturing TechnologyZhejiang University of TechnologyHangzhou 310000China School of Engineering London South Bank UniversityLondon SE10AAUK Shenzhen Jinzhou precision technology Corporation Shenzhen 518116China Department of Mechanical Engineering University of Petroleum and Energy StudiesDehradun 248007India Special Equipment Institute Hangzhou Vocational&Technical CollegeHangzhou 310018China

printed circuit boards(pCBs)are representative composite materials,and their high-quality drilling machining remains a persistent challenge in the *** finishing of the cutting edge of a microdrill is crucial to drill performance in machining fine-quality holes with a prolonged tool *** miniature size involving submicron scale geometric dimensions,a complex flute shape,and low fracture toughness makes the cutting edge of microdrills susceptible to breakage and has been the primary limiting factor in edge preparation for *** this study,a newly developed cutting edge preparation method for microdrills was tested experimentally on electronic printed circuit *** proposed method,namely,shear thickening polishing,limited the cutting edge burrs and chipping on the cutting edge,and this in turn transformed the cutting edge’s radius from being sharp to ***,the edge–edge radius could be regulated by adjusting the processing *** drilling experiments were conducted to investigate the influence of different cutting edge radii on wear,hole position accuracy,nail head value,and hole wall *** proposed approach showed 20%enhancement in hole position accuracy,33%reduction in the nail head value,and 19%reduction in hole wall roughness compared with the original ***,a threshold is needed;without it,excessive shear thickening polishing will result in a blunt edge,which may accelerate the wear of the *** was identified as the primary factor that reduced hole *** study indicates that in printed circuit board machining,microdrills should effectively eliminate grinding defects and maintain the sharpness of the cutting edge as much as possible to obtain excellent drilling ***,shear thickening polishing is a promising method for cutting edge preparation of *** research and optimization can lead to additional improvements in microdrill performance and contribute to the conti

关键词： microdrill shear thickening polishing cutting edge preparation electronic printed circuit boards hole quality

Hydrothermal treatment of pearl millet grains:Effects on nutritional composition,antinutrients and flour properties

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Grain & Oil Science and technology 2024年第2期7卷 87-95页

作者： p.prashanth t.jayasree Joshi Shagolshem Mukta Singh p.Srinivasa Rao Agricultural and Food Engineering Department Indian Institute of Technology KharagpurKharagpurWest Bengal 721302India

pearl millet(pennisetum glaucum)is one of the major millets with high nutritional *** crop exhibits exceptional resilience to drought and high ***,the processing of pearl millet poses a significant challenge due to its high lipid content,enzyme activity,and presence of ***,it becomes imperative to enhance the quality and prolong the shelf life of pearl millet flour by employing suitable *** treatment in the food industry has long been seen as promising due to its potential to reduce microbial load,inactivate enzymes,and improve nutrient *** study aims to investigate the effects of hydrothermal treatment on the quality characteristics of pearl *** 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 *** antinutrients like tannins and phytates were reduced by 0.99% to 5.94% and 0.36% to 6.00%,respectively,after the *** activity decreased significantly up to 10% with the treatment *** 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.

关键词： pearl millet Hydrothermal treatment Nutritional properties Antinutrients

technological advancements in millet dehulling and polishing process: An insight into pretreatment methods, machineries and impact on nutritional quality

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Grain & Oil Science and technology 2024年第3期7卷 186-195页

作者： Shagolshem Mukta Singh jayasree Joshi t p.Srinivasa Rao Agricultural and Food Engineering Department Indian Institute of Technology KharagpurKharagpurWest Bengal 721302India

Millets are widely recognized for their nutritional significance;however, the methods employed for their processing are currently lacking. this article primarily focuses on the advanced technologies and progressions in millet dehulling and polishing. these technologies operate based on the fundamental principles of compression-shearing, abrasion-friction, and centrifugal-impact forces. processing of millets can be challenging because of the physical characteristics and tight attachment of hull and bran to the endosperm. However, several dehullers have been designed to solve this problem for different kinds of millets. In addition, the nutritional and anti-nutritional characteristics undergo alterations due to both dehulling and polishing processes. these alterations are thoroughly examined and discussed in this article. Specifically, anti-nutrients such as tannins and phytate are predominantly found in the outer pericarp of the grain and experience a reduction after undergoing dehulling and polishing. the nutritional properties are also subjected to a reduction;however, this reduction can be mitigated by subjecting the grains to certain pretreatments before dehulling and polishing. these treatments serve to enhance dehulling efficiency and nutrient digestibility while simultaneously reducing the presence of anti-nutrients. Novel thermal and non-thermal methodologies such as microwave, hydrothermal, high-pressure processing, and ohmic heating can be employed for processing millets, thereby diminishing the loss of nutrients. Additional research can be carried out to investigate their impact on the dehulling and polishing of millets.

关键词： Millets Dehulling polishing pretreatment Novel thermal and non-thermal techniques

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美国页岩油气地质特征及勘探开发进展

石油勘探与开发 2024年第4期51卷 807-828页

作者： MCMAHON t p LARSON t E ZHANG t SHUStER M 美国德克萨斯大学奥斯汀分校杰克逊地质科学学院经济地质局奥斯汀78758-4445德克萨斯州美国

基于美国页岩油气勘探开发历程的回顾,对主要页岩盆地的地质演化、主要页岩层系的油气地质特征及勘探开发进展进行系统梳理和总结。美国重要页岩盆地的富烃页岩主要发育于6个地质时期:中奥陶世、中—晚泥盆世、早石炭世(中—晚密西西比... 详细信息

基于美国页岩油气勘探开发历程的回顾,对主要页岩盆地的地质演化、主要页岩层系的油气地质特征及勘探开发进展进行系统梳理和总结。美国重要页岩盆地的富烃页岩主要发育于6个地质时期:中奥陶世、中—晚泥盆世、早石炭世(中—晚密西西比世)、早二叠世、晚侏罗世和晚白垩世(塞诺曼期—土伦期),构造沉积环境主要包括克拉通内盆地、前陆盆地和被动大陆边缘盆地。古生界富烃页岩主要分布于以下6个盆地:阿巴拉契亚盆地(尤蒂卡页岩和马塞勒斯页岩)、阿纳达科盆地(伍德福德页岩)、威利斯顿盆地(巴肯页岩)、阿卡马盆地(费耶特维尔页岩)、沃思堡盆地(巴内特页岩)和二叠盆地(狼营组和斯帕瑞组/骨泉组页岩)。中生界富烃页岩主要发育在西墨西哥湾盆地(海恩斯维尔组和鹰滩组)和落基山盆地群(以丹佛和粉河盆地的尼尔布拉勒组页岩为主)。通过对各页岩区带的详细分析发现,页岩的岩相和矿物成分存在差异,“页岩储层”并非只是页岩,很多情况下页岩油气还产自粉砂岩和碳酸盐岩等多种岩石类型。美国的页岩油气资源丰富,页岩油地质资源量超过0.246×1012 t,页岩气地质资源量超过290×1012 m3。在开启“页岩革命”的水平井水力压裂技术出现之前,美国经过了长达20年的勘探开发实践和理论技术积累。自2007年至2023年,美国页岩油气产量从约11.2×104t/d油当量增加到超过300.0×104t/d油当量,2017年页岩油气产量超过了常规油气,2023年在油气总产量中的占比增加到60%以上。页岩油气的开发主要得益于钻完井技术的改进,“立体开发”的攻关,以及重复压裂、提高原油采收率和“U”形井等技术的应用。基于美国丰富的页岩资源基础和技术的不断进步,页岩油气的产量将继续为全美的油气生产做出更大贡献。

关键词：美国页岩油页岩气页岩储层非常规储层油气产量资源评价

paper Analytical Device for the Colourimetric Detection of Alkaline phosphatase in Serum and Saliva

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Journal of Analysis and testing 2024年第03期8卷 385-394页

作者： D.Alageswari A.LakshmiDevi p.E.Resmi p.V.Suneesh Aarathipradeep t.G.SatheeshBabu Department of Chemistry Amrita School of Physical Sciences Coimbatore Amrita Vishwa Vidyapeetham Amrita Biosensor Research Lab Amrita School of Engineering Coimbatore Amrita Vishwa Vidyapeetham Amrita Biomedical Engineering Centre Amrita School of Engineering Coimbatore Amrita Vishwa Vidyapeetham

A paper analytical device (pAD) was developed for the colourimetric estimation of alkaline phosphatase (ALp). ALp catalyzes the hydrolysis of disodium phenyl phosphate (DSpp) to phenol, which then undergoes oxidative coupling with4-aminoantipyrine (4-AAp) producing a reddish brown-coloured quinone imine. the colourimetric reaction tested in solution has been translated onto a pAD for the point of care (poC) testing of ALp. A uniform colour was obtained in 25 min with the introduction of ALp onto the reagent drop cast paper device. the images obtained by scanning the pAD were processed using ImageJ software. the colour intensity obtained by image processing was proportional to the concentration of ALp present in the sample. ALp in serum and saliva samples were tested using the pAD in the range of 0 to 528 U/L and0 to 187 U/L, respectively. the interference studies revealed that the pAD was selective to ALp in the presence of other biomolecules. the pAD exhibited a limit of detection (LOD) of 3.3 U/L and a sensitivity of 48.36 a.u/Log(U/L) for serum ALp and LOD of 1.69 U/L and a sensitivity of 28.5 a.u/Log (U/L) for salivary ALp. the pAD showed good agreement with the clinical methods for real samples.

关键词： Alkaline phosphatase Colourimetry ImageJ paper analytical device point of care testing

Development of endemicity and conservation importance indices for tropical forests and the floral diversity assessment of *** in Benguet,philippines

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Journal of Mountain Science 2024年第3期21卷 786-804页

作者： Johndale Rein t.BULLONG Jim p.SILVERIO Joanna I.ALAFAG Maricel A.GURON Jones t.NApALDEt Department of Environmental Science Benguet State UniversityLa Trinidad 2601Philippines Department of Biology Benguet State UniversityLa Trinidad 2601Philippines

the scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally ***,recent inventories in secondary tropical mountain forests using traditional biodiversity indices have yielded results that are indistinct with primary *** shows the need to develop complementary indices that goes beyond species count but integrates the distribution and conservation status of the *** study developed endemicity and conservation importance index for tropical forest that incorporated the distribution and conservation status of the *** indices were applied to ***,a remnant primary mossy forest in Buguias,Benguet,philippines,that resulted to endemicity index of 81.07 and conservation importance index of *** these with secondary forest sites with comparable Shannon-Wiener,Simpson,Evenness and Margalef’s indices,our endemicity and conservation indices clearly differentiates primary forest(our study site)with higher values from secondary forests with much lower ***,we are proposing these indices for a direct but scientifically-informed identification of specific sites for conservation and protection in tropical ***,our study documented a total of 168 vascular plant species(79 endemic and 12 locally threatened species)in *** are of tropical elements for both generic and species levels with some temperate elements that could be attributed to the site's high elevation and semi-temperate *** are important baseline information for conservation plans and monitoring of tropical mossy forests.

关键词： Endemicity index Conservation importance index Cordillera Central Range Floristic element Jaccard Index of Similarity

Multi-scale habitat influences sprainting and group size of a freshwater-obligate smooth-coated otter(Lutrogale perspicillata) in tungabhadra Otter Conservation Reserve, India

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Ecological processes 2024年第1期13卷 159-175页

作者： Ankit Moun p.Ramesh Kumar M.Malathi priya t.Ramesh Riddhika Kalle Sálim Ali Centre for Ornithology and Natural History Deputy Conservator of Forests Bellary Territorial Forest Division Deputy Conservator of Forests Working Plan and Survey and Research WingBellary Territorial Forest Division Centre for Functional Biodiversity University of Kwa Zulu-Natal

Background the impact of changing land-use patterns and associated anthropogenic threats on scale-dependent habitat use of semi-aquatic mustelids in scent-marking and social behaviour can provide important insights into the habitat ecology of smooth-coated otters(Lutrogale perspicillata).Methods We sampled 180 stream segments(100–400 m) as spatial replicates of 60 1-km2 sites to record indirect evidence(i.e. spraints and mass latrine sites) and group sizes of smooth-coated otters along the tungabhadra Otter Conservation Reserve(tOCR) during the dry season. to quantify habitat, we recorded stream characteristics, riparian vegetation, and anthropogenic disturbances at the local scale, and hydro-environmental characteristics and land uses at the landscape scale. Using Markovian-chain detection and occupancy models, we assessed the multi-scale habitat use of otters in their selection of suitable areas for scent-marking based on repeated presence-absence data on spraint/latrine locations along the tOCR. We further used linear regression techniques to explore relationships between the number of individuals in smooth-coated otter group and hydro-environmental characteristics, spraint/latrine encounter rate, anthropogenic pressure, land cover, topography, and *** At the local scale, the probability of spraint deposition and group size decreased with anthropogenic disturbance while the probability of spraint detections decreased with grass cover. At the landscape scale, the probability of otter site use for spraint deposition and group sizes increased in southeast flowing streams. Spraint deposition increased with the proportion of sugarcane fields, whereas in contrast, group size decreased with proportion of sugarcane *** Our findings highlight the first empirical evidence on multi-scale habitat use of a southern Indian population of smooth-coated otters in an inland freshwater ecosystem surrounded by the scrub jungle–agriculture matrix. We sug

关键词： presence-absence modelling Inland river Freshwater ecosystem Semi-aquatic mammal Smooth-coated otter

HI in High Gas-phase Metallicity Dwarf Galaxy WISEA J230615.06+143927.9

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Research in Astronomy and Astrophysics 2024年第1期24卷 292-299页

作者： Yan Guo C.Sengupta t.C.Scott p.Lagos Y.Luo purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China Institute of Astrophysics and Space Sciences(IA porto) Rua das Estrelas4150-762PortoPortugal

We present resolved Giant Metrewave Radio telescope H I observations of the high gas-phase metallicity dwarf galaxy WISEA J230615.06+143927.9(z = 0.005)(hereafter J2306) and investigate whether it could be a tidal Dwarf Galaxy(tDG) candidate. tDGs are observed to have higher metallicities than normal dwarfs. J2306 has an unusual combination of a blue g-r color of 0.23 mag, irregular optical morphology and high-metallicity(12 +log(O/H) = 8.68 ± 0.14), making it an interesting galaxy to study in more detail. We find J2306 to be an H I rich galaxy with a large extended, unperturbed rotating H I disk. Using our H I data we estimated its dynamical mass and found the galaxy to be dark matter(DM) dominated within its H I radius. the quantity of DM, inferred from its dynamical mass, appears to rule out J2306 as an evolved tDG. A wide area environment search reveals J2306 to be isolated from any larger galaxies which could have been the source of its high gas metallicity. Additionally, the H I morphology and kinematics of the galaxy show no indication of a recent merger to explain the *** detailed optical spectroscopic observations of J2306 might provide an answer to how a seemingly ordinary irregular dwarf galaxy achieved such a high level of metal enrichment.

关键词： galaxies:abundances galaxies:dwarf galaxies:irregular radio lines:galaxies radio lines:ISM

tensile deformation of fine-grained Mg at 4K,78K and 298K

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Journal of Magnesium and Alloys 2024年第6期12卷 2534-2556页

作者： M.Walag A.Kula p.Noga t.tokarski G.Cios M.Niewczas AGH University of Krakow Faculty of Non-Ferrous MetalsKrakowPoland AGH University of Krakow Academic Centre for Materials and NanotechnologyKrakowPoland Materials Science and Engineering McMaster UniversityHamiltonCanada

the impact of grain size, ranging from 0.9 μm to 9 μm, on the mechanical properties of commercially pure Mg is investigated at temperatures of 4K, 78K, and 298K. the mechanisms governing plastic flow are influenced by both grain size and temperature. At 4K and 78K, dominant deformation modes in Mg involve dislocation glide and extension twinning, regardless of grain size. the interactions between basal and non-basal dislocations and dislocations with grain boundaries promote an unusually high rate of work hardening in the plastic regime, leading to premature failure. the yield stress follows the Hall-petch relationship σy~ k/√d, with the slope k increasing with decreasing temperature. At 298K, in addition to dislocation glide and twinning, grain boundary sliding(GBS) becomes significant in samples with grain sizes below 3 μm, considerably enhancing the material's deformability. GBS activation provides an additional recovery mechanism for dislocations accumulating at grain boundaries, facilitating their absorption during sliding and rotation. Analysis of σ Θ relationship suggests that the basal slip is the dominant dislocation mode in Mg at 298K. Decreasing grain size suppresses dislocation activity and twinning and increases GBS, resulting in lower Θ and σ Θ values. Suppressing conventional deformation modes coupled with enhanced GBS yields stress softening, breaking down the Hall-petch relationship in Mg below 3 μm grain size, leading to an inverse Hall-petch behaviour. the work reports new data on the strength, ductility, work hardening and fracture behaviour, and their variations with Mg grain size across different temperature regimes.

关键词： polycrystalline Mg Mechanical properties Deformation mechanisms Work-hardening texture evolution Cryogenic temperatures Hall-petch relationship