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Tracing suspended and bed sediments during high and low water periods using geochemical characteristics-Case study:Vazrood watershed,northern Iran

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Journal of Mountain Science 2024年第2期21卷 470-483页

作者： KARIMI Nabiyeh GHOLAMI Leila KAVIAN Ataollah KHALEDI DARVISHAN Abdulvahed Department of Watershed Management Faculty of Natural ResourcesSari Agricultural Sciences and Natural Resources UniversitySari ***Iran Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoor ***Iran

Complete and comprehensive information about sediment dynamic and identification of hotspots of sediment production and transport are necessary for understanding the erosion processes and increasing the efficiency of soil and water conservation *** studies used the sediment fingerprint techniques to investigate the contribution of different sources in suspended and bed sediment yield of the ***,the contribution of various land use/land covers in suspended and bed sediment yield for the great Caspian Sea basin is in an aura of ambiguity and the present study was conducted to gather information about an important part of this area in northern Iran,where rangelands are located upstream of Hyrcanian forests and dense agricultural lands are located *** surface soil of different land use/land covers including forest,rangeland,agriculture and streambank lands were sampled in 30 *** and bed sediments were sampled in the watershed outlet in two high and low water *** characteristics of soil and sediment samples containing 59 elements were measured using ICP-OES GBC *** reliable and suitable tracers from 59 elements were then selected using Range test,Kruskal-Wallis and Discriminant Function Analysis,respectively,in FingerPro package of R *** results showed that for suspended sediment,streambank and rangeland had the highest contributions of 86.2.and 47.5%,respectively,in two high and low water *** bed sediment,in two high and low water periods,rangeland and streambank had the highest contributions of 73.8%and 84.4%,*** use change and especially human activities such as agriculture,road construction and development of residential areas along the main river riparian zone has led to a significant increase in suspended and bed sediments.

关键词： Caspian Sea basin FingerPro Geochemistry Sediment transport Tracer combination

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Sequential alkaline-organic acid leaching process to enhance the recovery of rare earth elements from Indonesian coal fly ash

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Journal of Rare Earths 2024年第7期42卷 1366-1374,I0006页

作者： Widya Rosita Indra Perdana I Made Bendiyasa Ferian Anggara Himawan Tri Bayu Murti Petrus Agus Prasetya Isyatun Rodliyah Department of Nuclear Engineering and Engineering Physics Faculty of EngineeringUniversitas Gadjah MadaJl Grafika No.2Yogyakarta55281Indonesia Department of Chemical Engineering Faculty of EngineeringUniversitas Gadjah MadaJl Grafika No.2Yogyakarta55281Indonesia Department of Geological Engineering Faculty of EngineeringUniversitas Gadjah MadaJl Grafika No.2Yogyakarta55281Indonesia Unconventional Geo-resources Research Group Faculty of EngineeringUniversitas Gadjah MadaJl Grafika No.2Yogyakarta55281Indonesia Center for Testing of Mineral and Coal Tekmira-Directorate General of Mineral and Coal-Ministry of Energy and Mineral resources Jl.Jend.Sudirman No.623Wr.MuncangKec.Bandung KulonKota BandungJawa Barat40211Indonesia

In this decade,coal fly ash(CFA)is considered a potential secondary source of rare earth elements(REEs).However,most REEs in coal fly ash are encapsulated in aluminosilicate glass,making it challenging to recover them through acid *** this study,a sequential alkaline-organic acid leaching was developed for the recovery of REEs from *** effect of alkaline leaching using NaOH solution on the destructive ability of aluminosilicate glass,as well as the mineralogy and morphology changes of the resulting coal fly ash,was first ***,the effectiveness of alkaline leaching on the recovery ability of REEs through organic acid leaching was *** results show that the maximum leaching efficiency for Si and Al,which was obtained at the optimum alkaline leaching conditions,namely NaOH concentration of 10 mol/L,reaction temperature of 65℃,liquid/solid(L/S)ratio of 10 mL/g,and reaction time of 90 min,is 2.%and 32.,*** digestion reaction with NaOH lixiviants also causes coal fly ash to become more porous,making it advantageous in the organic acid-leaching process at the REEs recovery *** utilization of the desilicated residue produced from the digestion process in acid leaching effectively increases the overall REEs recovery from 32.2.to 77.6%.

关键词： Rare earth elements Alkaline Organic acid Coal fly ash

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Annual growth of Fagus orientalis is limited by spring drought conditions in Iran’s Golestan Province

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Journal of Forestry Research 2024年第1期35卷 128-142页

作者： Khalil Ghorbani Jahangir Mohammadi Laleh Rezaei Ghaleh Department of Water Engineering Faculty of Water and Soil EngineeringGorgan University of Agricultural Sciences and Natural ResourcesGorganIran Department of Forestry Gorgan University of Agricultural Sciences and Natural ResourcesGorganIran Department of Water Engineering Faculty of AgricultureUrmia UniversityUrmiaIran

Due to the lack of a uniform and accurate defi-nition of‘drought’,several indicators have been introduced based on different variables and methods,and the efficiency of each of these is determined according to their relationship with *** relationship between two drought indices,SPI(standardized precipitation index)and SPEI(standard-ized precipitation-evapotranspiration index)in different sea-sons was investigated using annual rings of 15 tree samples to determine the effect of drought on the growth of oriental beech(Fagus orientalis Lipsky)in the Hyrcanian forests of northern *** different evapotranspiration calcula-tion methods were evaluated on SPEI efficiency based on Hargreaves-Samani,Thornthwaite,and Penman-Monteith methods using the step-by-step M5 decision tree regression *** results show that SPEI based on the Penman-Monteith in a three-month time scale(spring)had similar temporal changes and a better relationship with annual tree rings(R^(2.=0.81)at a 0.05 significant *** change and a decreasing trend in the time series of annual tree rings are similar to the variation in the SPEI based on the Penman-Monteith *** affecting evapotranspiration,temperature,wind speed,and sunshine hours(used in the Penman-Monteith method),increased but precipitation *** non-linear modeling methods,SPEI based on Penman-Monteith best illustrated climate changes affecting tree growth.

关键词： Climate change Drought index Hyrcanian forests SPEI'Annual growth rings Fagus orientalis

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Sedimentary records of contaminant inputs in Frobisher Bay,Nunavut

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Environmental Science and Ecotechnology 2024年第2期18卷 28-42页

作者： Meaghan C.Bartley Tommy Tremblay Amila O.De Silva CMichelle Kamula Stephen Ciastek Zou Zou A.Kuzyk Centre for Earth Observation Science Clayton H.Riddell Faculty of EnvironmentEarth and ResourcesUniversity of ManitobaWinnipegManitobaR3T 2N2Canada Department of Environment and Geography Clayton H.Riddell Faculty of EnvironmentEarth and ResourcesUniversity of ManitobaWinnipegManitobaR3T 2N2Canada Canada-Nunavut Geoscience Office IqaluitNunavutX0A 0H0Canada Environment and Climate Change Canada BurlingtonOntarioL7S 1A1Canada Department of Earth Sciences Clayton H.Riddell Faculty of EnvironmentEarth and ResourcesUniversity of ManitobaWinnipegManitobaR3T 2N2Canada

Contaminants,such as polychlorinated biphenyls(PCBs),polycyclic aromatic hydrocarbons(PAHs),heavy metals,and per and polyfluoroalkyl substances(PFASs),primarily reach the Arctic through long-range atmospheric and oceanic ***,local sources within the Arctic also contribute to the levels observed in the environment,including legacy sources and new sources that arise from activities associated with increasing commercial and industrial *** City of Iqaluit in Frobisher Bay,Nunavut(Canada),has seen rapid population growth and associated development during recent decades yet remains a site of interest for ocean protection,where Inuit continue to harvest country *** the present study,seven dated marine sediment cores collected in Koojesse Inlet near Iqaluit,and from sites in inner and outer Frobisher Bay,respectively,were analyzed for total mercury(THg),major and trace elements,PAHs,PCBs,and *** sedimentary record in Koojesse Inlet shows a period of Aroclor 12.0-like PCB input concurrent with military site presence in the 1950e60s,followed by decades of input of pyrogenic PAHs,averaging about ten times background ***-surface sediments in Koojesse Inlet also show evidence of transient local-source inputs of THg and PFASs,and recycling or continued slow release of PCBs from legacy land-based *** in PFAS congener composition clearly distinguish the local sources from long-range *** Koojesse Inlet but still in inner Frobisher Bay,9.2.km from Iqaluit,sediments showed evidence of both local source(PCB)and longrange *** outer Frobisher Bay,an up-core increase in THg and PFASs in sediments may be explained by ongoing inputs of these contaminants from long-range *** context for ocean protection and country food harvesting in this region of the Arctic clearly involves both local sources and long-range transport,with past human activities leaving a long legacy insofar as levels of persistent o

关键词： Arctic sediments Mercury Polycyclic aromatic hydrocarbons(PAHs) Polychlorinated biphenyls(PCBs) Per and polyfluoroalkyl substances(PFASs) Persistent organic pollutants(POPs)

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Challenges in applying REE-based thermobarometers: Insights from mafic-ultramafic granulites in Indian southern granulite terrain

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Science China Earth Sciences 2024年第11期67卷 3448-3464页

作者： Xiaofei XU Longlong GOU Chengli ZHANG Junsheng LU Yan ZHAO Wenhao AO Yuhua HU Feng ZHOU faculty of Land resources Engineering Kunming University of Science and Technology State Key Laboratory of Continental Dynamics Department of Geology Northwest University

High-temperature diffusion of major elements may obscure the records of early and peak metamorphic stages in granulites,while trace elements are more likely to preserve these records due to their lower diffusion ***,using calibrated REE-based thermobarometers has proved essential for reconstructing these key stages,drawing considerable attention and application from ***,the precision of these thermobarometers depends on including both major and trace elements from coexisting minerals to define the correlation coefficients（A,B,and D） among mineral pairs,indicating that the elemental composition of these pairs can affect the *** study examines the mafic-ultramafic granulites in the southern granulite terrain,India,employing integrated methods such as petrography,mineral chemistry,phase equilibrium modeling,and REE-based *** aim to determine their metamorphic conditions and evolutionary history and to identify potential challenges in using REE-based *** garnet,clinopyroxene,and orthopyroxene in the mafic-ultramafic granulite samples display homogeneous compositional profiles,with pronounced Fe-Mg diffusion zones at the interfaces between garnet and ***,the profiles of trace elements within garnet and clinopyroxene are better *** into Fe-Mg exchange and randomly selected mineral pairs significantly influence the accuracy of REE-based ***-Mg exchange can increase in coefficient A,while decreasing coefficient B for light rare earth elements（LREEs） and increasing it for heavy rare earth elements（HREEs）,ultimately resulting in overestimations when calculating REE-based *** example,selecting major compositions with an Ex(=(XMgC-XMg0)/XMg0×100%;where XMgCis the value after Fe-Mg exchange,XMg0is the value before Fe-Mg exchange;XMg=Mg/(Fe2.+Mg)) value of ～10 for calculation using the REE-in-Grt-Cpx thermobarometer will result in pressures and t

关键词： Granulites REE-based thermobarometer Fe-Mg exchange Randomly selected mineral pairs

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Flotation separation of scheelite from calcite using luteolin as a novel depressant

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 462-472页

作者： Xiaokang Li Ying Zhang Haiyang He Yu Wu Danyu Wu Zhenhao Guan faculty of Land and resources Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Clean Utilization of Complex Non-Ferrous Metal resources Kunming University of Science and TechnologyKunming 650093China

This paper proposes luteolin(LUT)as a novel depressant for the flotation-based separation of scheelite and calcite in a sodium oleate(NaOL)*** suitability of LUT as a calcite depressant is confirmed through micro-flotation *** pH=9,with LUT concentration of 50 mg·L^(-1) and NaOL concentration of 50 mg·L^(-1),scheelite recovery reaches 80.3%.Calcite,on the other hand,exhibits a recovery rate of 17.6%,indicating a significant difference in floatability between the two ***,the surface modifica-tions of scheelite and calcite following LUT treatment are characterized using adsorption capacity testing,Zeta potential analysis,Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),and atomic force microscopy(AFM).The study in-vestigates the selective depressant mechanism of LUT on *** capacity testing and Zeta potential analysis demonstrate sub-stantial absorption of LUT on the surface of calcite,impeding the further adsorption of sodium oleate,while its impact on scheelite is ***-IR and XPS analyses reveal the selective adsorption of LUT onto the surface of calcite,forming strong chemisorption bonds between the hydroxyl group and calcium ions *** directly illustrates the distinct adsorption densities of LUT on the two miner-al ***,LUT can effectively serve as a depressant for calcite,enabling the successful separation of scheelite and calcite.

关键词： scheelite calcite luteolin flotation depressant separation

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Hydrodynamic Assessment of A New Nature-Based Armour Unit on Rubble Mound Breakwater for Coastal Protection

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China Ocean Engineering 2024年第3期38卷 439-452页

作者： Ehsan SAFA Alireza MOJTAHEDI Abdolmajid MOHAMMADIAN Mohamad Ali Lotfollahi YAGHIN Department of Water resources Engineering Faculty of Civil EngineeringUniversity of TabrizTabriz ***Iran faculty of Civil Engineering University of OttawaOttawa K1H 8M5Canada

This research proposes a novel nature-based design of a new concrete armour unit for the cover layer of a rubblemoundbreakwater. Armour units are versatile with respect to shape, orientation, surface condition details, and ***, a detailed analysis is required to investigate the exact state of their hydraulic interactions and structuralresponses. In this regard, the performance results of several traditional armour units, including the Antifer cube,Tetrapod, X-block and natural stone, are considered for the first step of this study. Then, the related observed resultsare compared with those obtained for a newly designed (artificial coral) armour unit. The research methodology utilizesthe common wave flume test procedure. Furthermore, several verified numerical models in OpenFOAM code areused to gain the extra required data. The proposed armour is configured to provide an effective shore protection as anenvironmental-friendly coastal structure. Thus it is designed with a main trunk including deep grooves to imitate thetypical geometry of a coral type configuration, so as to attain desirable performance. The observed results and ananalytic hierarchy process (AHP) concept are used to compare the hydraulic performance of the studied traditionaland newly proposed (artificial coral) armour units. The results indicate that the artificial coral armour unit demonstratesacceptable performance. The widely used traditional armour units might be replaced by newer designs for betterwave energy dissipation, and more importantly, for fewer adverse effects on the marine environment.

关键词： rubble mound breakwater hydraulic interaction armour unit analytic hierarchy process numerical model

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Changes in climatic conditions drive variations in arbuscular mycorrhizal fungi diversity and composition in semi-arid oak forests

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Journal of Forestry Research 2024年第5期35卷 106-119页

作者： Nahid Jafarian Javad Mirzaei Reza Omidipour Yahya Kooch Department of Forest Science Faculty of AgricultureIlam UniversityIlam 69315-516Iran Department of Range and Watershed Management Faculty of AgricultureIlam UniversityIlam 69315-516Iran faculty of Natural resources and Marine Sciences Tarbiat Modares UniversityNoor 46417-76489MazandaranIran

Arbuscular mycorrhizal fungi(AMF)play a vital role in plant productivity and ecosystem ***,their responses to abiotic factors(i.e.,climate,physiography,and soil properties)are unknown,especially across climatic gradients and slope aspects in arid and semi-arid *** this study,using 60 composite soil samples,direct and indirect effects of climate factors and slope aspects on AMF diversity,composition and spore density were *** findings indicate that climate has a more direct influ-ence on soil properties(P<0.001)in comparison to slope aspect(P=0.449).In contrast,climate significantly affected AMF diversity and composition,with the highest diversity in dryer *** pH had the highest correlation with different facets of AMF *** equation modeling(SEM)indicated that only a small part of the variation in AMF diversity and spore density could be explained by climate characteristics,slope aspect and soil *** on SEM results,climate was the most important determinant of AMF diversity and spore density;slope aspect had a less critical *** outputs suggest that variations in AMF diversity are derived by the direct effects of climate and the indirect effect of soil chemical *** addition,with increasing dryness,sporulation and AMF diversity increased.

关键词： AMF diversity and composition Physiographic factors Semi-arid ecosystems Zagros forest

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Extract lithium from clay-type lithium ore by mixed acid and its mechanism Author links open overlay panel

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Particuology 2024年第8期91卷 323-332页

作者： Wuchang Zhou Ruiqi Xie Xiong Tong Xian Xie Yang Liu Zhihui Zhao faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming650093China Technology Innovation Center for Comprehensive Utilization of Strategic Mineral resources Ministry of Natural ResourcesChengdu610041China National&Regional Engineering Research Center for Green comprehensive Utilization of Tailing resources from Metal Minerals Kunming650093China

A roasting-leaching test was carried out for the efficient utilization of clay-type lithium ore in the central region of Yunnan *** test used the mixed acid of sulfuric acid and phosphoric acid as the leaching *** the conditions of roasting temperature of 600℃,roasting time of 1 h,liquid-solid ratio of 5:1,volume ratio of H_(2.SO_(4)solution to H_(3)PO_(4)solution of 45:5,leaching time of 2.h and leaching temperature of 80℃,the leaching rate of lithium was as high as 97.83%.The leaching mechanism was studied by SEM,pore property analysis,XRD and *** was found that the morphology of the ore changed obviously after roasting and leaching,and a certain degree of collapse and fragmentation occurred,which provided favorable spatial conditions for the leaching of *** porosity,total intrusion volume and total pore area also increased after roasting and leaching,thus promoting the leaching of Li^(+).The results showed that chemical reaction taken placed during the roasting and *** phase of the sample changed from chlorite,kaolinite and diaspore(boehmite)mainly to corundum,hematite,periclase and quartz after ***,after leaching,no new phase was produced in the ore sample,and no S and P elements were found on the surface of the ore sample,indicating that the leaching mechanism of lithium might be the ion exchange between H^(+)and Li^(+).

关键词： Clay-type lithium ore Lithium extraction Roasting Leaching

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Thermodynamic theory of flotation for a complex multiphase solid -liquid system and high-entropy flotation

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1177-1197页

作者： Shuming Wen State Key Laboratory of Complex Nonferrous Metal resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China

The flotation of complex solid–liquid multiphase systems involve interactions among multiple components,the core problem facing flotation ***,the combined use of multicomponent flotation reagents to improve mineral flotation has become an important issue in studies on the efficient use of refractory mineral ***,studying the flotation of complex solid–liquid systems is extremely difficult,and no systematic theory has been developed to *** addition,the physical mechanism associated with combining reagents to improve the flotation effect has not been unified,which limits the development of flotation theory and the progress of flotation *** this study,we applied theoretical thermodynamics to a solid–liquid flotation system and used changes in the entropy and Gibbs free energy of the reagents adsorbed on the mineral surface to establish thermodynamic equilibrium equations that de-scribe interactions among various material components while also introducing adsorption equilibrium constants for the flotation reagents adsorbed on the mineral *** homogenization effect on the mineral surface in pulp solution was determined using the chemical potentials of the material components of the various mineral surfaces required to maintain *** flotation effect can be improved through synergy among multicomponent flotation reagents;its physical essence is the thermodynamic law that as the number of compon-ents of flotation reagents on the mineral surface increases,the surface adsorption entropy change increases,and the Gibbs free energy change of adsorption *** to the results obtained using flotation thermodynamics theory,we established high-entropy flotation theory and a technical method in which increasing the types of flotation reagents adsorbed on the mineral surface,increasing the adsorption entropy change of the flotation reagents,decreasing the Gibbs free energy change,and improving the adsorption efficiency

关键词： multicomponent flotation reagent adsorption entropy change equations of thermodynamic equilibrium adsorption equilibri-um constant high-entropy flotation

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