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Quantitative mineralogical characterization of chrome ore beneficiation plant tailing and its beneficiated products 被引量:1
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作者 S.K.Das 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第4期335-345,共11页
Mineralogical characterization and liberation of valuable minerals are primary concerns in rnineml processing industries. The pre- sent investigation focuses on quantitative mineralogy, elemental deportment, and locki... Mineralogical characterization and liberation of valuable minerals are primary concerns in rnineml processing industries. The pre- sent investigation focuses on quantitative mineralogy, elemental deportment, and locking-liberation characteristics of the beneficiation of tailings from a chrome ore beneficiation plant in the Sukinda region, Odisha; methods used for the study of the beneficiated tailings are QEMSCAN~, X-ray diffraction (XRD), and mineral chemistry by a scanning electron microscope equipped with an energy-dispersive spec- trometer (SEM-EDS). The tailing sample was fine grained (69.48wt% below 45 μm size), containing 20.25wt% Cr203 and 39.19wt% Fe203, with a Cr:Fe mass ratio of 0.51. Mineralogical investigations using QEMSCAN studies revealed that chromite, goethite, and gibbsite are the dominant mineral phases with minor amounts of hematite, kaolinite, and quartz. The sample contained 34.22wt% chromite, and chromite liberation is more than 80% for grains smaller than 250 ~tm in size. Based on these results, it was predicted that liberated chromite and high-grade middling chromite particles could be separated from the gangue by various concentration techniques. The tailing sample was beneficiated by hydrocyclone, tabling, wet high-intensity magnetic separation (WHIMS), and flotation in order to recover the chromite. A chromite concentrate with 45.29wt% Cr203 and a Cr:Fe mass ratio of 1.85 can be produced from these low-grade chromite ore beneficiation plant rejects. 展开更多
关键词 TAILINGS MINERALOGY CHROMITES BENEFICIATION
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Where is plant beneficial element research heading?
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作者 Zhihao Pang Nina Nikolic +2 位作者 Miloslav Nikolic Alexander Lux Yongchao Liang 《Journal of Integrative Agriculture》 2026年第3期829-846,共18页
Maintaining optimal crop nutritional levels is crucial for maximizing yield and enhancing stress resistance.In addition to the 17 essential nutrients,there are many plant-beneficial elements:silicon,aluminum,selenium,... Maintaining optimal crop nutritional levels is crucial for maximizing yield and enhancing stress resistance.In addition to the 17 essential nutrients,there are many plant-beneficial elements:silicon,aluminum,selenium,titanium,iodine,vanadium,cobalt,sodium,and rare earth elements.They are not essential for all plants,but some are crucial for specific plant species.However,the mechanisms of action of many beneficial elements are still unclear,and products containing beneficial elements have not been widely accepted and used by the public.This review systematically summarizes the current knowledge of plant-beneficial elements.Most importantly,we offer suggestions for future research on beneficial elements,which include integrating cross-disciplinary and innovative technologies,expanding the scope of application and elemental spies,broadening the spatial and temporal scales of research,incorporating beneficial elements into the soil health evaluation system,and shifting from single to multi-element applications.In the future,research on beneficial elements should be closely centered around“mechanism+application”to meet the ever-increasing demands driven by population growth,improve human health,tackle environmental challenges,and promote rural economic development. 展开更多
关键词 plant nutrients beneficial elements FERTILIZER soil health
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Harnessing plant-rhizobacteria alliances for nutrient homeostasis in depleting soil landscape:Shifting paradigms beyond chemical fertilizers
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作者 Nikita BISHT Tanya SINGH +1 位作者 Mohd Mogees ANSARI Puneet Singh CHAUHAN 《Pedosphere》 2026年第1期342-357,共16页
The excessive reliance on chemical inputs for managing soil nutrients and pathogens has raised concerns about their long-term sustainability and environmental impact.In contrast,the use of soil microbes offers an eco-... The excessive reliance on chemical inputs for managing soil nutrients and pathogens has raised concerns about their long-term sustainability and environmental impact.In contrast,the use of soil microbes offers an eco-friendly and efficient alternative for improving soil fertility and plant growth.Beneficial microorganisms,including plant growth-promoting rhizobacteria(PGPR),mycorrhizal fungi,and other soil organisms,play pivotal roles in nutrient cycling,organic matter decomposition,and nutrient availability improvement.This review explores the potential of leveraging microbial resources for sustainable soil nutrient management and resilient crop production.It delves into the intricate interactions between host plants and PGPR,particularly under nutrient-limited and fluctuating environmental conditions,with a focus on the molecular signaling pathways and mechanisms regulating these relationships.Furthermore,it emphasizes the role of advanced techniques and PGPR-responsive microRNAs to uncover the functional capabilities of microbial communities and their dynamic interactions with plants.These approaches pave the way for developing innovative,microbe-based strategies to optimize nutrient use efficiency,reduce dependency on synthetic fertilizers,and support sustainable agricultural practices. 展开更多
关键词 beneficial microorganisms BIOFERTILIZERS nutrient imbalance plant growth promoting rhizobacteria plant nutrition soil degradation soil fertility sustainability
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Distribution and Fate of Arsenic in Copper Mining,Beneficiation and Smelting in China
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作者 HAN Wei WANG Yujing NIE Jinglei 《有色金属(中英文)》 北大核心 2025年第10期1844-1853,共10页
Copper smelting is the main source of arsenic pollution in the environment,and China is the largest country for copper smelting.Taking 2022 as an example,this study analyzes the distribution and fate of arsenic across... Copper smelting is the main source of arsenic pollution in the environment,and China is the largest country for copper smelting.Taking 2022 as an example,this study analyzes the distribution and fate of arsenic across the copper mining,beneficiation,and smelting processes using a life-cycle approach,providing important insights for arsenic pollution prevention and the resource utilization of arsenic-bearing solid waste.The results show that the amount of As in waste rock,tailing and concentrate are 53483 t,86632 t,76162 t,respectively.After smelting treatment,the amount of arsenic in different types of solid waste,wastewater,waste gas and products are 76128 t,1 t,31 t and 2 t,respectively,and the proportion in arsenic sulfide slag is the highest(55%).The amount of emission to the environment is 32 t,accounting for only 0.04%of total amount.In the future,key considerations are to improve the resource utilization rate of arsenic-containing solid waste(tailing,smelting slag),especially arsenic sulfide slag,and to digest its environmental risk. 展开更多
关键词 arsenic contamination copper mining copper beneficiation copper smelting material flow
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Effects of Seed Priming and Foliar Application of Selenite,Nanoselenium,and Microselenium on Growth,Biomolecules,and Nutrients in Cucumber Seedlings
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作者 Oscar Sarinana-Aldaco Carmen Alicia Ayala-Contreras +6 位作者 Susana González-Morales Gregorio Cadenas-Pliego Marissa Pérez-Alvarez América Berenice Morales-Díaz Dámaris Leopoldina Ojeda-Barrios JoséGerardo Uresti-Porras Adalberto Benavides-Mendoza 《Phyton-International Journal of Experimental Botany》 2025年第7期2131-2153,共23页
Selenium(Se)is a nutrient that is considered beneficial for plants,because its improvement in growth,yield and quality helps plants to mitigate stress.The objective of this research was to evaluate the application of ... Selenium(Se)is a nutrient that is considered beneficial for plants,because its improvement in growth,yield and quality helps plants to mitigate stress.The objective of this research was to evaluate the application of sodium selenite(Na2SeO3),nanoparticles(SeNPs)and microparticles(SeMPs)of Se in cucumber seedlings,via two experiments:one with seed priming and the other with foliar application of Sematerials.The doses used were:0,0.1,0.5,1.0,1.5 and 3.0 mg⋅L^(−1),for each form of Se and for each form of application.Treatment 0 consisted of the application of distilled water,which was used as a control.The results indicated that the SeMPs treatment at 3.0 mg⋅L^(−1)for seed priming had the greatest effect on stem diameter and leaf area.Foliar application of SeMPs at 1.5 mg⋅L^(−1)was the most effective at increasing the leaf area.In terms of fresh and dry biomass(aerial,root and total)for seed priming,all the treatments were superior to the control,and SeMPs at 1.5 and 3.0 mg⋅L^(−1)caused the greatest effects.With foliar application,fresh root biomass improved to a greater extent with the SeMPs treatment at 3.0 mg⋅L^(−1),and dry biomass(aerial,root and total)increased with the SeMPs at 1.0 and 3.0 mg⋅L^(−1).With respect to the photosynthetic pigments,proteins,phenols and minerals,the Se treatments,both for seed priming and foliar application,caused increases and decreases;however,reduced glutathione(GSH)increased with treatments in both forms of application.The Se concentration in the seedlings increased as the dose of Se material increased,and greater accumulation was achieved with foliar application of SeNPs and SeMPs.The results indicate that the use of Se materials is recommended,mainly the use of SeMPs,which improved the variables studied.This opens new opportunities for further studies with SeMPs,as little information is available on their application in agricultural crops. 展开更多
关键词 Beneficial nutrients biostimulants NANOMATERIALS micromaterials PHYTOCHEMICALS sodium selenite
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Jointly Building a Future of Shared Prosperity
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作者 YAO JING 《China Today》 2025年第5期37-40,共4页
The mutually beneficial cooperation between China and Spain is not only an epitome of but also a model for the development of China-EU relations.
关键词 model China EU relations mutually beneficial cooperation jointly building shared prosperity China Spain
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A comprehensive evaluation of the potential of plant growth-promoting rhizobacteria for applications in agriculture in stressed environments
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作者 Naila RAFIQUE Sadia KHALIL +3 位作者 Massimiliano CARDINALE Aysha RASHEED Fengliang ZHAO Zainul ABIDEEN 《Pedosphere》 2025年第1期229-248,共20页
The world is facing a consistent increase in human population and a noticeable decrease in cultivable lands due to soil salinization,abrupt climatic changes,and less rainfall.These problems have increased the importan... The world is facing a consistent increase in human population and a noticeable decrease in cultivable lands due to soil salinization,abrupt climatic changes,and less rainfall.These problems have increased the importance of finding ecologically sustainable solutions to ensure global food security.Plant growth-promoting rhizobacteria can be advantageous to enhancing plant productivity and safeguarding against environmental stresses.They may assist plants by atmospheric nitrogen fixation,nutrient recycling,phosphate solubilization,iron sequestration via siderophore formation,and production of phytohormones like indole-3-acetic acid and 1-aminocyclopropane-1-carboxylate deaminase.They can also be used as biofertilizers and biocontrol agents as they produce antibiotics,exopolysaccharides,and hydrolytic enzymes.In this review,the connections between microbial populations,as microbial inoculants,and plant systems are highlighted,focusing on the enhancement of plant development,environmental resilience of agricultural systems,ecosystem services,and biological challenges under stressed conditions.This review also emphasizes the use of advanced molecular tools and techniques to effectively characterize potent soil microbial communities,their importance in increasing crop yield in stressed soils,and the prospects for future research. 展开更多
关键词 abiotic stress beneficial microbes BIOMASS food security land degradation multi-omics
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Lower size limit of raw coal for efficient beneficiation in air-fluidized bed with magnetite particles
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作者 Yalong Cao Donghui Liu Quanhong Zhu 《Chinese Journal of Chemical Engineering》 2025年第9期158-166,共9页
A feasible criterion was established to determine the lower size limit of raw coal(d_(pRm))for efficient beneficiation in the air-fluidized bed with magnetite particles.The feasibility of using small magnetite particl... A feasible criterion was established to determine the lower size limit of raw coal(d_(pRm))for efficient beneficiation in the air-fluidized bed with magnetite particles.The feasibility of using small magnetite particles to accommodate the fine raw coal was demonstrated from the experimental perspective.The minimum size for the magnetite particles to be fluidized smoothly was clarified as 47.1μm,which corresponded to the border between Geldart-B and-A groups.Since the gangue and coal components in the raw coal were crushed into the same size,d_(pRm)depended on the greater one between d_(pGm)(minimum size required for the gangue particles to sink towards the bottom)and d_(pCm)(minimum size required for the coal particles to float towards the top).dpcm was determined as 259μm by supposing that provided the gangue particles accumulated in the lower half bed,they could be potentially extracted from the bottom.On the other hand,it was observed that the coal particles could always accumulate in the upper half bed.Under such circumstances,dpcm was revealed as 9.8μm since finer coal particles would be blown out by air before the 47.1μm sized magnetite particles became fluidized.Eventually,dpRm was clarified as 259μm,agreeing with the common view that raw coal coarser than 6 mm could be effectively beneficiated in the air-fluidized bed with magnetite particles.Additionally,the difficulty in beneficiating the fine raw coal was revealed to arise more from the remixing of sorted gangue particles than that of separated coal particles. 展开更多
关键词 Raw coal Dry beneficiation Fluidized bed Lower size limit Magnetite particles
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China-EU Cooperation Could Not Have Been Better Timed--On the Occasion of the 50th Anniversary of China-EU Diplomatic Relations
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作者 《Contemporary World》 2025年第4期22-27,共6页
This year marks the 50th anniversary of the establishment of diplomatic relations between China and the EU.Over half a century,China and the EU have steadily enhanced political mutual trust,deepened mutually beneficia... This year marks the 50th anniversary of the establishment of diplomatic relations between China and the EU.Over half a century,China and the EU have steadily enhanced political mutual trust,deepened mutually beneficial cooperation,and firmly upheld multilateralism,bringing tangible benefits to both peoples and making a significant contribution to global peace and development. 展开更多
关键词 EU Mutually Beneficial Cooperation Political Mutual Trust China Diplomatic Relations enhanced political mutual trustdeepened establishment diplomatic relations MULTILATERALISM
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A Mutually Beneficial Platform
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《ChinAfrica》 2025年第7期2-2,共1页
When the fourth China-Africa Economic and Trade Expo(CAETE)was unveiled on 12 June,Changsha,the capital city of central China’s Hunan Province,came into the spotlight.The four-day event has provided a window showcasi... When the fourth China-Africa Economic and Trade Expo(CAETE)was unveiled on 12 June,Changsha,the capital city of central China’s Hunan Province,came into the spotlight.The four-day event has provided a window showcasing the steady and rapid growth of the China-Africa eco-nomic and trade partnership. 展开更多
关键词 China Africa economic trade partnership Hunan province China Africa economic trade expo rapid growth Changsha mutually beneficial platform steady growth
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Backwash Effects of Language Testing in EFL Classrooms
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作者 赵秦岭 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2002年第S3期100-105,共6页
The article presents some major researches concerning the concept of backwash effect of language testing; analyses both the positive and negative effects and their implications in EFL classrooms; then provides some su... The article presents some major researches concerning the concept of backwash effect of language testing; analyses both the positive and negative effects and their implications in EFL classrooms; then provides some suggested ways to be followed when creating positive backwash effects on teaching and learning. 展开更多
关键词 BACKWASH EFFECT positive/beneficial negative/harmful EFL CLASSROOMS
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Beneficiated cassiterite(SnO_(2))from mining tailings-to-clean renewable energy storage material:unlocking the potential sustainability
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作者 Rawan A.Elshwehy Mohamed M.Hamdy +3 位作者 Aya M.Abuelftooh Sayed Y.Attia Saad G.Mohamed Mona M.Fawzy 《Clean Energy》 2026年第1期140-157,共18页
Research on developing sustainable materials for devices to store clean energy has become crucial.This study explores the use of naturally occurring cassiterite(SnO2),a rare metal oxide mineral,as a material for elect... Research on developing sustainable materials for devices to store clean energy has become crucial.This study explores the use of naturally occurring cassiterite(SnO2),a rare metal oxide mineral,as a material for electrodes in supercapacitors.The mineral is found in mining tailings of the Igla Be-Sn deposit(Egypt’s Central Eastern Desert)mined from pegmatitic granite and greisen zones.The mineral(3.59%mass)was beneficiated using a sequence of sorting,magnetic,and gravity separation.The physico-chemical characterization indicated stoichiometric SnO2 of nanoscale grains with high crystallinity,porous structure,and many electroactive sites.Using a three-electrode configuration with a 6M KOH electrolyte,the electrochemical performance was assessed via cyclic voltage measurements,galvanostatic charge-discharge,and electrochemical impedance spectroscopy.The cassiterite-based electrode shows specific capacitance of 54.97 F g^(−1) and a capacity of 30.23 C g^(−1) under an electrical density of 1 A g^(−1),and capacitive storage(retention)of 293.8%over 3000 cycles,which paired with enhanced charge transfer and ion diffusion characteristics.Cassiterite from Igla mining tailings has been proven to be a sustainable substitute for traditional electrode materials in clean energy storages due to the developed electrode’s electrical efficacy,the enormous amount of Igla Sn tailings,and the economical and environmentally friendly recovery techniques used. 展开更多
关键词 Igla Sn mining tailings Egypt’s Central Eastern Desert physical beneficiation physico-chemical characterization electrochemical performance supercapacitors application
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Review of tungsten resource reserves,tungsten concentrate production and tungsten beneficiation technology in China 被引量:38
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作者 Xu WANG Wen-qing QIN +4 位作者 Fen JIAO Liu-yang DONG Jian-gen GUO Jian ZHANG Cong-ren YANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第7期2318-2338,共21页
Tungsten is a strategic metal that is widely used in various fields such as electron communication,aeronautics and astronautics,materials and chemical engineering,due to its special properties.China has the largest re... Tungsten is a strategic metal that is widely used in various fields such as electron communication,aeronautics and astronautics,materials and chemical engineering,due to its special properties.China has the largest reserves of tungsten resources and the largest output of tungsten concentrate in the world,and plays a decisive role in the world tungsten market.In this work,firstly,the reserves and distribution characteristics of tungsten resources in China were summarized,and the production situation of tungsten concentrate in China was reviewed.Based on the gross domestic product per capita(GDP/capita),five different annual GDP growth rates were used to estimate China’s tungsten concentrate production in the future.The estimation results suggested that if China’s economy continues to grow at the current rate,the accumulative production of tungsten concentrate will exceed current reserves by approximately 2032.Then,from the aspects of process flow,beneficiation equipment and flotation reagents,the beneficiation technology development of different types of tungsten ore in China was also reviewed,including wolframite,scheelite and tungsten-bearing slime.Finally,taking several representative tungsten mines in China as examples,the classic beneficiation technology of different types of tungsten ores was elucidated in detail.Meanwhile,the development direction of tungsten beneficiation technology in the future was put forward,which was of great significance to maintain the superiority of tungsten resources in China. 展开更多
关键词 TUNGSTEN RESERVES PRODUCTION BENEFICIATION FLOTATION gravity separation
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Soil-Plant-Microbe Interactions in Stressed Agriculture Management:A Review 被引量:30
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作者 Shobhit Raj VIMAL Jay Shankar SINGH +1 位作者 Naveen Kumar ARORA Surendra SINGH 《Pedosphere》 SCIE CAS CSCD 2017年第2期177-192,共16页
The expected rise in temperature and decreased precipitation owing to climate change and unabated anthropogenic activities add complexity and uncertainty to agro-industry. The impact of soil nutrient imbalance, misman... The expected rise in temperature and decreased precipitation owing to climate change and unabated anthropogenic activities add complexity and uncertainty to agro-industry. The impact of soil nutrient imbalance, mismanaged use of chemicals, high temperature, flood or drought, soil salinity, and heavy metal pollutions, with regard to food security, is increasingly being explored worldwide. This review describes the role of soil-plant-microbe interactions along with organic manure in solving stressed agriculture problems. Beneficial microbes associated with plants are known to stimulate plant growth and enhance plant resistance to biotic (diseases) and abiotic (salinity, drought, pollutions, etc.) stresses. The plant growth-promoting rhizobemteria (PGPR) and mycorrhizae, a key component of soil microbiota, could play vital roles in the maintenance of plant fitness and soil health under stressed environments. The application of organic manure as a soil conditioner to stressed soils along with suitable microbial strains could further enhance the plant-microbe associations and increase the crop yield. A combination of plant, stress-tolerant microbe, and organic amendment represents the tripartite association to offer a favourable environment to the proliferation of beneficial rhizosphere microbes that in turn enhance the plant growth performance in disturbed agro-ecosystem. Agriculture land use patterns with the proper exploitation of plant-microbe associations, with compatible beneficial microbial agents, could be one of the most effective strategies in the management of the concerned agriculture lands owing to climate change resilience. However, the association of such microbes with plants for stressed agriculture management still needs to be explored in greater depth. 展开更多
关键词 beneficial microbes FUNGI microbial agents rnycorrhiza organic manure PATHOGEN plant health plant growth-promoting rhizobacteria
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Review on development of low-grade scheelite recovery from molybdenum tailings in Luanchuan, China: A case study of Luoyang Yulu Mining Company 被引量:17
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作者 Xu WANG Wen-qing QIN +6 位作者 Fen JIAO Cong-ren YANG Wei LI Zheng-quan ZHANG Jin-min ZHOU Jian-gen GUO Jian ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第3期980-998,共19页
Luanchuan area is one of the regions with the largest scale of scheelite beneficiation and the largest output of scheelite concentrate in the world. After years of innovation and progress, the beneficiation technology... Luanchuan area is one of the regions with the largest scale of scheelite beneficiation and the largest output of scheelite concentrate in the world. After years of innovation and progress, the beneficiation technology of low-grade scheelite associated with molybdenum tailings in Luanchuan area is becoming more and more perfect. In this study, the development process of low-grade scheelite recycling technology in Luanchuan area was reviewed, including raw ore properties, beneficiation process, flotation equipment and flotation reagents. Meanwhile, taking Luoyang Yulu Mining Co., Ltd. as an example, the effects of various technical transformations such as the optimization of the beneficiation process, the column-machine combined process, and the high-efficiency flotation reagents were elucidated in detail. However, the recycling technology of low-grade scheelite of Luanchuan area is still possible to be improved. As a result, coupled with the latest research progress, the development direction of low-grade scheelite beneficiation in Luanchuan area was also prospected. It is of great significance to further improve the recovery efficiency of low-grade scheelite resources in Luanchuan area and this can provide technical reference for other scheelite plants. 展开更多
关键词 SCHEELITE low-grade ore BENEFICIATION FLOTATION RECOVERY
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Recovery of iron from copper slag by deep reduction and magnetic beneficiation 被引量:15
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作者 Ke-qing Li Shuo Ping +1 位作者 Hong-yu Wang Wen Ni 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第11期1035-1041,共7页
Aiming at recovering iron from high-iron-content copper slag, this article introduced a combination technol- ogy of deep reduction and magnetic beneficiation, investigated the iron recovery efficiency and optimized th... Aiming at recovering iron from high-iron-content copper slag, this article introduced a combination technol- ogy of deep reduction and magnetic beneficiation, investigated the iron recovery efficiency and optimized the technical conditions. When coke powder with 86wt% fixed carbon was used as a reductant, iron was successfully extracted from the copper slag. Under the optimized condition of the coke powder content of 14wt%, the calcium-to-silicon mass ratio (Ca/Si) of 0.2, the roasting temperature of 1300℃, the roasting time of 3 h, the grinding time of 20 min, and the magnetic field intensity of 61 kA-m-1, the iron recovery rate of the copper slag can reach 91.82%, and the extracted iron powder has an iron grade of 96.21%. With the characteristics of high iron grade and low impurity content, the extracted iron powder can be used as high-quality raw materials of weathering steel. 展开更多
关键词 copper slag waste utilization ore reduction magnetic separation BENEFICIATION
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Leukocytes and oxidative stress: dilemma for sperm Function and male fertility 被引量:15
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作者 Ralf R Henkel 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第1期43-52,共10页
Spermatozoa are constantly exposed to the interphase between oxidation through high amounts of reactive oxygen species (ROS) and leukocytes, and reduction by means of scavengers and antioxidants. Considering the ver... Spermatozoa are constantly exposed to the interphase between oxidation through high amounts of reactive oxygen species (ROS) and leukocytes, and reduction by means of scavengers and antioxidants. Considering the very special functions as being the only cells with such high polarization and exerting their functions outside the body, even in a different individual, the female genital tract, the membranes of these cells are chemically composed of an extraordinary high amount of polyunsaturated fatty acids. This in turn, renders them very susceptible to oxidative stress, which is defined as an imbalance between oxidation and reduction towards the oxidative status. As a result, ROS deriving from both leukocytes and the male germ cells themselves cause a process called 'lipid peroxidation' and other damages to the sperm cell. On the other hand, a certain limited amount of ROS iS essential in order to trigger vital physiological reactions in cells, including capacitation or the acrosome reaction in sperm. The treatment of patients with antioxidants to compensate the oxidative status caused by oxidative stress is highly debated as uncontrolled antioxidative treatment might derail the system towards the reduced status, which is also unphysiological and can even induce cancer. This paradox is called the 'antioxidant paradox'. Therefore, a proper andrological diagnostic work-up, including the evaluation of ROS levels and the antioxidant capacity of the semen, has to he carried out beforehand, aimed at keeping the fine balance between oxidation and scavenging of vital amounts of ROS. 展开更多
关键词 ANTIOXIDANTS BALANCE beneficial effects detrimental effects leukocytes male infertility reactive oxygen species sperm functions
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Exercise sustains the hallmarks of health 被引量:22
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作者 Yan Qiu Benjamin Fernández-García +4 位作者 H.Immo Lehmann Guoping Li Guido Kroemer Carlos López-Otín Junjie Xiao 《Journal of Sport and Health Science》 SCIE CSCD 2023年第1期8-35,共28页
Exercise has long been known for its active role in improving physical fitness and sustaining health.Regular moderate-intensity exercise improves all aspects of human health and is widely accepted as a preventative an... Exercise has long been known for its active role in improving physical fitness and sustaining health.Regular moderate-intensity exercise improves all aspects of human health and is widely accepted as a preventative and therapeutic strategy for various diseases.It is well-documented that exercise maintains and restores homeostasis at the organismal,tissue,cellular,and molecular levels to stimulate positive physiological adaptations that consequently protect against various pathological conditions.Here we mainly summarize how moderate-intensity exercise affects the major hallmarks of health,including the integrity of barriers,containment of local perturbations,recycling and turnover,integration of circuitries,rhythmic oscillations,homeostatic resilience,hormetic regulation,as well as repair and regeneration.Furthermore,we summarize the current understanding of the mechanisms responsible for beneficial adaptations in response to exercise.This review aimed at providing a comprehensive summary of the vital biological mechanisms through which moderate-intensity exercise maintains health and opens a window for its application in other health interventions.We hope that continuing investigation in this field will further increase our understanding of the processes involved in the positive role of moderate-intensity exercise and thus get us closer to the identification of new therapeutics that improve quality of life. 展开更多
关键词 Beneficial effects of exercise Exercise-related physiological adaptations Hallmarks of health Moderate-intensity exercise Therapeutic exercise
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Recent process developments in beneficiation and metallurgy of rare earths:A review 被引量:16
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作者 Shaokai Cheng Wenbo Li +3 位作者 Yuexin Han Yongsheng Sun Peng Gao Xiaolong Zhang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第4期629-642,共14页
Rare earth elements(REEs)are irreplaceable materials supporting low-carbon technology and equip-ment,and their commercial demand and strategic position are becoming increasingly prominent.With the continuous depletion... Rare earth elements(REEs)are irreplaceable materials supporting low-carbon technology and equip-ment,and their commercial demand and strategic position are becoming increasingly prominent.With the continuous depletion of rare earth(RE)resources,developing high-efficiency beneficiation and eco-friendly metallurgical processes has attracted widespread attention.This paper reviews the major minerals exploited for RE production and their deposits,as well as the beneficiation and metallurgical processes of RE minerals.Bastnaesite,monazite,mixed RE ores,and ion-adsorption clays are the main raw materials in the world to date.RE-bearing ores(except ion-adsorption minerals)are generally beneficiated by flotation,gravity and magnetic separation techniques.The mainstream metallurgical processes for bastnaesite,monazite and mixed RE concentrates are oxidation roasting-HCl leaching,caustic soda decomposition and high-temperature concentrated sulfuric acid roasting,respectively.Ion-adsorption clays are directly processed by in situ leaching-precipitation/solvent extraction.To achieve the sustainable development of RE resources,it is essential to further explore innovative techniques to achievecomprehensive utilization and cleaner production. 展开更多
关键词 Rare earths Beneficiation processes Metallurgical processes Cleaner production
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Mineralogy and carbothermal reduction behaviour of vanadium-bearing titaniferous magnetite ore in Eastern India 被引量:10
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作者 Saikat Samanta Manik Chandra Goswami +2 位作者 Tapan Kumar Baidya Siddhartha Mukherjee Rajib Dey 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第10期917-924,共8页
Vanadium-beaxing titaniferous magnetite bands hosted by Precambrian gabbro-norite-anorthositic rocks or their metamorphic equivalents were discovered in some parts of Eastern Indian Shield, containing 48%-49% Fe (to... Vanadium-beaxing titaniferous magnetite bands hosted by Precambrian gabbro-norite-anorthositic rocks or their metamorphic equivalents were discovered in some parts of Eastern Indian Shield, containing 48%-49% Fe (total), 10%-25% TiO2, and 0.3%-2.20% V2O5 by mass. Mineralogical and petrological study, composition, and characterization of the vanadium-bearing titaniferous magnetite ore were carried out by scanning electron microscopy-energy dispersive X-ray (SEM-EDX), wave length X-ray florescence (WDXRF), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), X-ray diffraction (XRD), etc. Chemical beneficiation for valuable metals, such as Fe, Ti, andV, was performed by reduction roasting. The direct and indirect reduction were investigated by mixing the lump ore with solid activated charcoal in a closed reactor and purging the reducing gas mixture in standard reducibility index apparatus at different temperatures and time intervals. The reduction roasting parameters were optimized. Finally, the reduced samples were crushed and upgraded by magnetic separation. The results show that, the maximum mass fractions of magnetic and nonmagnetic parts achieved axe 69.36% and 30.64%, respectively, which contain 10.6% TiO2 and 0.84% V205 in the magnetic part and 36.5% TiO2 and 0.22% V205 in the nonmagnetic part. 展开更多
关键词 MAGNETITE MINERALOGY carbothermal reduction BENEFICIATION VANADIUM
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