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Petrology of Spinel-Lherzolite Xenoliths from Mazéléand Others Northen Xenoliths Localities of Cameroon Volcanic Line: Exchange Reactions and Equilibrium State

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Open Journal of Geology 2024年第5期14卷 629-653页

作者： Nguihdama Dagwai Kamgang Pierre Mbowou Gbambié isaac Bertrand Chazot Gilles Ngounouno Ismaïla Department of Life and Earth Sciences Higher Teachers&#8217 Training College University of Maroua Maroua Cameroon Department of Earth Sciences Faculty of Science University of Yaound&#233 1 Yaound&#233 Cameroon Department of Mineral Prospecting and Exploration Technologies School of Geology and Mining Engineering University of Ngaoundere Meiganga Cameroon Ocean Geosciences Laboratory European University Institute of the Sea (IUEM) Brest France

The alkaline volcanism of the Cameroon Volcanic Line in its northern domain has raised many fresh enclaves of peridotites. The samples selected come from five (05) different localities (Liri, in the plateau of Kapsiki, Mazélé in the NE of Ngaoundéré, Tello and Ganguiré in the SE of Ngaoundéré and Likok, locality located in the west of Ngaoundé). The peridotite enclaves of the above localities show restricted mineralogical variation. Most are four-phase spinel-lherzolites, indicating that this is the main lithology that forms the lithospheric mantle below the shallow zone. No traces of garnet or primary plagioclase were detected, which strongly limits the depth range from which the rock fragments were sampled. The textures and the wide equilibrium temperatures (884˚C - 1115˚C) indicate also entrainment of lherzolite xenoliths from shallow depths within the lithosphere and the presence of mantle diapirism. The exchange reactions and equilibrium state established in this work make it possible to characterize the chemical composition of the upper mantle of each region and test the equilibrium state of the phases between them. Variations of major oxides and incompatible elemental concentrations in clinopyroxene indicate a primary control by partial melting. The absence of typical “metasomatic” minerals, low equilibration temperatures and enriched LREE patterns indicate that the upper mantle below septentrional crust of Cameroun underwent an event of cryptic metasomatic enrichment prior to partial melting. The distinctive chemical features, LREE enrichment, strong U, Ce and Pr, depletion relative to Ba, Nb, La, Pb, and T, fractionation of Zr and Hf and therefore ligh high Zr/Hf ratio, low La/Yb, Nb/La and Ti/Eu are all results of interaction of refractory peridotite residues with carbonatite melts.

关键词： Xenoliths Upper Mantle Northern Region Adamawa Cameroon Volcanic Line Exchange Reaction

间隙水交换重塑区域和全球盐沼的碳和温室气体收支

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中国科学：地球科学 2024年第7期54卷 2227-2242页

作者：陈小刚 isaac R.SANTOS 詹泸成邱渝茵张龑李凌西湖大学工学院浙江省海岸带环境与资源研究重点实验室杭州310024 Department of Marine Sciences University of GothenburgGothenburg 41319Sweden 河海大学水利水电学院南京210024

盐沼是一种富含碳的生态系统,通过有效地固定大气中的CO_(2),在气候调节中发挥着重要的作用.然而,气候变化对盐沼造成了严重威胁,可能会影响盐沼的碳汇过程.在此背景下,间隙水交换(PEX)碳排放作为一项重要但一直被忽视的碳循环过程应受... 详细信息

盐沼是一种富含碳的生态系统,通过有效地固定大气中的CO_(2),在气候调节中发挥着重要的作用.然而,气候变化对盐沼造成了严重威胁,可能会影响盐沼的碳汇过程.在此背景下,间隙水交换(PEX)碳排放作为一项重要但一直被忽视的碳循环过程应受到重视.本文系统评估了盐沼中碳和温室气体排放的驱动因素,揭示了PEX作为主要过程对碳和温室气体动态变化的调控作用.通过综合分析全球33个盐沼PEX案例后发现,全球盐沼PEX碳通量约占全球盐沼初级生产力的48%,超过全球盐沼有机碳埋藏量的2.2倍.这一发现突显了PEX在盐沼碳收支中的主导作用.尽管PEX排放的部分无机碳以CO_(2)形式返回大气中,但剩余的碳酸盐会在海洋中长期稳定储存.因此,这项研究对于加强全球蓝碳评估,并为利用盐沼作为基于自然的解决方案来应对全球气候变化提供了科学依据.

关键词：岸碳全球碳收支碳中和基于自然的解决方案滨海湿地海底地下水排放

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AI与CFO职能转变

新理财（公司理财） 2024年第2期 88-90页

作者： isaac Heller 不详

随着CFO在技术决策中发挥的作用越来越大,他们完全可以运用AI和自动化技术来优化财务运营。人工智能(AI)既影响着财务领域的技术,如财务软件,也影响着财务部门负责人的职责范围,如CFO的职责。从CFO的角度来看,采用AI和自动化技术对有效... 详细信息

随着CFO在技术决策中发挥的作用越来越大,他们完全可以运用AI和自动化技术来优化财务运营。人工智能(AI)既影响着财务领域的技术,如财务软件,也影响着财务部门负责人的职责范围,如CFO的职责。从CFO的角度来看,采用AI和自动化技术对有效管理财务运营、推动业务增长和最大化企业价值是至关重要的。最重要的是,在AI的帮助下,CFO将更专注于高层战略决策,而不是日常的会计事项管理、记录和报告工作。

关键词：财务部门负责财务运营自动化技术 CFO 职责范围财务软件会计事项战略决策

Characterization of Small-Scale Farmers and Assessment of Their Access to Crop Production Information in Selected Counties of Kenya

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Agricultural Sciences 2024年第5期15卷 565-589页

作者： Anastasia Mumbi Wahome John B. K. Kiema Galcano C. Mulaku isaac Mukoko Department of Geospatial & Space Technology University of Nairobi Nairobi Kenya Department of Public Health Kenya Methodist University Nairobi Kenya

Small-scale farming accounts for 78% of total agricultural production in Kenya and contributes to 23.5% of the country’s GDP. Their crop production activities are mostly rainfed subsistence with any surplus being sold to bring in some income. Timely decisions on farm practices such as farm preparation and planting are critical determinants of the seasonal outcomes. In Kenya, most small-scale farmers have no reliable source of information that would help them make timely and accurate decisions. County governments have extension officers who are mandated with giving farmers advisory services to farmers but they are not able to reach most farmers due to facilitation constraints. The mode and format of sharing information is also critical since it’s important to ensure that it’s timely, well-understood and usable. This study sought to assess access to geospatial derived and other crop production information by farmers in four selected counties of Kenya. Specific objectives were to determine the profile of small-scale farmers in terms of age, education and farm size;to determine the type of information that is made available to them by County and Sub-County extension officers including the format and mode of provision;and to determine if the information provided was useful in terms of accuracy, timeliness and adequacy. The results indicated that over 80% of the farmers were over 35 years of age and over 56% were male. Majority had attained primary education (34%) or secondary education (29%) and most farmers in all the counties grew maize (71%). Notably, fellow farmers were a source of information (71%) with the frequency of sharing information being mostly seasonal (37%) and when information was available (43%). Over 66% of interviewed farmers indicating that they faced challenges while using provided information. The results from the study are insightful and helpful in determining effective ways of providing farmers with useful information to ensure maximum benefits.

关键词： Small Scale Farmers Farmers Crop Production Information Services Geospatial Information Information Access

Effect of Variety and Plant Spacing on Growth and Yield of Groundnuts (Arachis hypogaea L.)

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Agricultural Sciences 2024年第1期15卷 54-70页

作者： Abukari Iddrisu Eric Adjei Samuel Kwesi Asomaning Kwadwo Gyasi Santo Adu Poku isaac Alexander Danson-Anokye Cocoa Health and Extension Division Huni Valley Ghana Department of Agriculture Berekum East Municipal Assembly Berekum Ghana Department of Horticulture and Crop Production School of Agriculture and Technology University of Energy and Natural Resources Sunyani Ghana Glenn High School Winston Salem USA

A field experiment was carried out to determine the effect of variety and plant spacing on yield and growth of groundnuts. The field experiment was laid in a 3 × 3 factorial experiment in a Randomized Complete Block Design (RCBD) with three (3) replications. The factor A included three (3) groundnut varieties (Nkatie Sari, Sum Nutt 22 and Yenyawoso) and Factor B was the three (3) spacing of 30 cm × 15 cm, 30 cm × 30 cm and 30 cm × 40 cm. All recommended agronomic practices were followed. Data was collected from eight (8) tagged plants. Growth data were recorded on plant height, number of branches, number of leaves, and the number of flowers while yield data were collected on the number of flowers, number of pods per plant, 100 seeds weight and the pod yield (kg/ha). The plant spacing significantly influenced (P enyawoso variety with a wider plant spacing performed better vegetatively among all the varieties. The Yenyawoso variety produced the highest number of pods, 100 seeds weight and pod yield as compared to the other varieties. Also, Yenyawoso at 30 cm × 40 cm spacing and Nkatie Sari at 30 cm × 15 cm spacing produced the maximum pod yield.

关键词： Groundnut Variety Yield Spacing Plant Height

Structural Controls and Predictive Mapping of Tin, Niobium and Tantalum Mineralization Associated with the Mayo Darlé Stanniferous Granitoids;Contributions of Geostatistics

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Journal of Geoscience and environment Protection 2024年第1期12卷 180-210页

作者： Bah-Yero Liman Ngounouno Ismaïla Mbowou Gbambié isaac Bertrand Alpha Baster Kenfack Fokem André William Boroh Amadou Diguim Kepnamou Department of Earth Sciences Faculty of Science University of Ngaoundéré Ngaoundéré Cameroon Department of Mining Geology School of Geology and Mining and Engineering University of Ngaoundéré Meiganga Cameroon Department of Earth Sciences Faculty of Science University of Garoua Garoua Cameroon

The aim of this study of the spatial dispersion of tin, niobium and tantalum mineralization associated with the Mayo Darlé granitoids was to produce prospecting guides through predictive maps of Sn, Nb and Ta in the region. It was based on a database (in appendix) obtained after analysis of rock samples (greisens and quartz veins) collected in the field, using a portable X-ray fluorescence (XRF) spectrometer. Two approaches were used: 1) structural studies in the field using the directions of veins and fractures 2) the use of variographic maps, an essential element in geostatistics for determining directional anisotropies. A joint synthesis of the modelling results shows that tin, tantalum and niobium mineralization at Mayo Darlé is concentrated along strike intervals N315E to N320E, with mineralization also occurring along strike N35E for high-grade Sn, medium-grade Ta and low-grade Nb. In short, mineral concentrations disperse progressively in space: positively from east to west for tantalum and niobium, and inversely for tin.

关键词： Mayo Darlé Tin Niobium Tantalum Geostatistics Mapping

An in vitro Anti-urolithiasis Activity of a Herbal Formulation:Spinacia oleracea *** Coriandrum sativum L.

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Clinical Complementary Medicine and Pharmacology 2024年第1期4卷 76-84页

作者： Sumathy Raj Monica Shree Gnana Soundara Rajan Suganthi Ramasamy Rimal isaac Rajamony Suthies Goldy Ramathilaga Ariyamuthu Monisha Sudhagar Sakthivel Gandhi Prakash Shoba Manikandan Gurusamy School of Biotechnology Dr.G.R.Damodaran College of ScienceCoimbatoreTamil NaduIndia Department of Biotechnology Dr.N.G.P Arts and Science CollegeCoimbatoreTamil NaduIndia Department of Nanotechnology Noorul Islam Centre for Higher EducationKumaracoilThuckalayKanyakumari DistrictTamil NaduIndia PG and Research Department of Biochemistry Kongunadu Arts and Science CollegeCoimbatoreTamil NaduIndia Department of Biological and Chemical engineering Mekelle UniversityMekelleEthipoia Department of Zoology Holy Cross College(Autonomous)NagercoilTamilnaduIndia Department of Pharmaceutical Sciences Tshwane University of TechnologyArcadia CampusPretoriaSouth Africa

Background:Hard mineral and acid salt deposits that clump together in concentrated urine are known as kidney stones.A complicated chain of physicochemical events,including hyper saturation,nucleation,growth,aggrega-tion,and retention in the urinary tract,leads to urolithiasis,the third most prevalent urinary tract *** traditional medications and therapies are less successful in treating urolithiasis and frequently cause ***:The present study is focused on evaluating the anti-urolithiasis activities of the polyherbal formulation prepared from Spinacia oleracea *** Coriandrum sativum ***:To evaluating the anti-urolithiasis activities of the polyherbal formulation prepared from *** and *** seeds against oxalate crystals by employing an in vitro inhibition,aggregation,and nucleation assay,employing a spectrophotometer followed by microscopic observation,and further monitored by egg semiperme-able membrane model,using cystone as a standard ***:In the present work,the alkaloids,glycosides,flavonoids,glycosides,phenols,saponins,steroids,tannins,terpenoids,and triterpenoids were found in the extracts of *** and *** in vitro assays in the present study clearly indicated that all the mixture extracts readily prevented crystal nucleation,growth and *** aqueous extract of the mixture inhibited significant inhibitory potential against the crystallization ***:It can be said that the phyto-constituents enriched homemade preparation possibly will be used as a medication for the management of kidney stones by dissolving the oxalate stone in the kidney.

关键词： Urolithiasis Polyherbal Egg membrane Spinacia oleracea Coriandrum sativum

Publisher’s Erratum to:Metamaterial-based graphene thermal emitter

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Nano Research 2024年第6期17卷 5753-5753页

作者： Cheng Shi Nathan H.Mahlmeister isaac J.Luxmoore Geoffrey R.Nash College of engineering Mathematics and Physical SciencesUniversity of ExeterExeterEX44QFUK

The article"Metamaterial-based graphene thermal emitter",written by Cheng Shi,Nathan ***,***,and Geoffrey ***,was originally published electronically on the publisher’s internet portal(currently SpringerLink)on December 6th 2017 without open *** the author(s)’decision to opt for Open Choice the copyright of the article changed in February 2018 to©The Author(s)2018 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License(http://***/licenses/by/4.0/),which permits use,duplication,adaptation,distribution and reproduction in any medium or format,as long as you give appropriate credit to the original author(s)and the source,provide a link to the Creative Commons license and indicate if changes were *** original article has been corrected.

关键词： emitter license creative

Effect of functional composite coating developed via sulphate and chloride process parameter on the UNS G10150 steel for structural and wear mitigation in defence application

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Defence Technology（防务技术） 2018年第3期14卷 196-203页

作者： Ojo Sunday isaac Fayomi Department of Mechanical engineering Covenant University Department of Chemical Metallurgical and Materials Engineering Tshwane University of Technology

The major engineering challenge of materials in defence technologies is the vulnerability of based metals to structural and wears deformation in service. In this paper, structural formation, mechanical and thermal stability behavior of developed composite coating of Zn-30 Al-7%Ti/Sn chloride bath and Zn-30 Al-7%Ti/Sn sulphate bath was investigated and compared to provide mitigation against failure. The thermal ageing property was done for 2 h at 600C via isothermal furnace. The structural, interfacial effect and stability behaviors of the co-deposited alloys were evaluated using scanning electron microscope equipped with energy dispersive spectrometer(SEM/EDS), atomic force microscope(AFM) and Xray diffractometer(XRD). The hardness and wear properties of the deposited coatings were examined with diamond base micro-hardness tester and reciprocating sliding tester respectively. The result shows that Zn-30 Al-7%Ti/Sn sulphate co-deposition contributed to increase hardness and wear resistance than Zn-30 Al-7%Ti/Sn chloride bath alloy. The stable crystal growth and significant performance of Zn-30 Al-7%Ti/Sn sulphate are link to the intermetallic phase hybrid of Zn Al, Zn4 Ti Al2, Zn3 Al Ti. Besides, it was observed that Zn-30 Al-7%Ti/Sn sulphate has excellent thermomechanical stability at harsh temperature,due to the deposition of Sn/Ti on steel; leading to formation of super-hard interface. However, it was established that co-deposition of mild steel with Zn-30 Al-7%Ti/Sn in sulphate bath significantly improved the structural and wear performance. It was shown that the hardness and wear of the developed composite Zn-30 Al-7%Ti/Sn is increased by about 80% compared to as received sample and about 25% compared with Zn-30 Al-7%Ti/Sn chloride coating developed. The improvement was proved to be an interference of zinc-composite growth. Thus, this work shows that sulphate induced Zn-30 Al-7%Ti/Sn via generation of controllable process parameter can provide significant improv

关键词：防卫技术硫酸盐氯化物低碳钢结构涂层合成 UNS