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High-pressure minerals and new lunar mineral changesite-(Y) in Chang’e-5 regolith

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Matter and Radiation at Extremes 2024年第2期9卷 90-97页

作者： Jing Yang Wei Du Center for Lunar and Planetary Sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of Sciences(CAS)Guiyang 550081China CAS Center for Excellence in Comparative Planetology Hefei 230026China

Forty-five years after the Apollo and Luna missions, China’s Chang’e-5 (CE-5) mission collected ∼1.73 kg of new lunar materials from one ofthe youngest basalt units on the Moon. The CE-5 lunar samples provide opportunities to address some key scientific questions related to theMoon, including the discovery of high-pressure silica polymorphs (seifertite and stishovite) and a new lunar mineral, changesite-(Y). Seifertitewas found to be coexist with stishovite in a silica fragment from CE-5 lunar regolith. This is the first confirmed seifertite in returned lunarsamples. Seifertite has two space group symmetries (Pnc2 and Pbcn) and formed from an α-cristobalite-like phase during “cold” compressionduring a shock event. The aftershock heating process changes some seifertite to stishovite. Thus, this silica fragment records different stagesof an impact process, and the peak shock pressure is estimated to be ∼11 to 40 GPa, which is much lower than the pressure condition forcoexistence of seifertite and stishovite on the phase diagram. Changesite-(Y), with ideal formula (Ca_(8)Y)◻Fe^(2+)(PO_(4))_(7) (where ◻ denotes avacancy) is the first new lunar mineral to be discovered in CE-5 regolith samples. This newly identified phosphate mineral is in the form ofcolumnar crystals and was found in CE-5 basalt fragments. It contains high concentrations of Y and rare earth elements (REE), reaching upto ∼14 wt. % (Y,REE)2O3. The occurrence of changesite-(Y) marks the late-stage fractional crystallization processes of CE-5 basalts combinedwith silicate liquid immiscibility. These new findings demonstrate the significance of studies on high-pressure minerals in lunar materials andthe special nature of lunar magmatic evolution.

关键词： evolution minerals basalt

In-situ U-Pb Dating of Quartz:A Preliminary Study

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Journal of Earth Science 2024年第2期35卷 726-728页

作者： Entao Liu Jian-Xin Zhao Songqi Pan Detian Yan Hua Wang Hubei Key Laboratory of Marine Geological Resources China University of GeosciencesWuhan 430074China Radiogenic Isotope Facility School of Earth and Environmental SciencesThe University of QueenslandBrisbane Qld 4072Australia PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China Key Laboratory of Tectonics and Petroleum Resources Ministry of EducationChina University of GeosciencesWuhan 430074China

CHALLENGES AND RESEARCH PROGRESS Recent advancements in analytical capabilities and the precision of measuring instruments in in-situ laser ablation mass spectrometry(LA-MC-ICPMS)have markedly broad ened the utility of the U-Pb isotopic geochronometer.This progress has paved the way for accurately determining the ab solute ages of minerals with low uranium concentrations.In re cent years,in-situ U-Pb dating has witnessed rapid advance ments across diverse mineral types,encompassing calcite,dolo mite,fluorite,nacrite,anatase,and wolframite(Roberts et al.,2020).

关键词： dating minerals isotopic

Phase engineering activation of low-cost iron-containing sulfide minerals for advanced electrocatalysis

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Journal of Materials Science & Technology 2022年第16期111卷 181-188页

作者： Jun Mei Qian Zhang Hong Peng Ting Liao Ziqi Sun Centre for Materials Science Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia School of Chemistry and Physics Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Chemical Engineering The University of QueenslandBrisbaneQLD 4072Australia School of Mechanical Medical and Process Engineering Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia

Sustainable energy conversion and storage provide feasible approaches towards green energy solutions and carbon neutralization.The high cost and complex fabrication process of advanced energy nanomaterials,however,has impeded the practical application of emerging sustainable technologies.The direct use of earth-abundant natural minerals which contain active elements for effective catalysis and energy storage should be a promising approach to achieve affordable sustainable energy supply and green fuel generations.Herein,as typical examples of activating natural minerals for electrocatalysis,two common minerals,pyrite and chalcopyrite,are activated via a one-step phase transformation strategy.Through a facile thermal reduction process,the minerals are completely transformed into active pyrrhotite(FeS)and haycockite(Cu_(4)Fe_(5)S_(8))phases.The thermal reduction resulting phase transformation can lead to significant surface disordering and can contribute to the catalytic activity by offering favourable electronic structure for intermediates adsorption,abundant surficial active centres,and substantial surface redox pairs.The activated minerals are examined for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)catalysis.The obtained haycockite phase delivers the best performance towards acidic HER and alkaline OER.Further phase optimization is performed via loading a low percentage of iridium nanoclusters on the haycockite phase deposited onto a carbon cloth substrate,through which an overpotential as low as 310 mV for achieving 10 mA cmand a small Tafel slope of 55.6 m V dec-1are recorded for alkaline OER.This work demonstrates the feasibility of the direct use of cost-effective natural resources for addressing the current energy-related issues and paves a way to reach affordable practical emerging sustainable technologies.

关键词： minerals Phase transformation Sulfides Oxygen evolution Electrocatalysis

Advanced silicon nanostructures derived from natural silicate minerals for energy storage and conversion

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Green Energy & Environment 2022年第2期7卷 205-220页

作者： Hao Wan Wei Ma Kechao Zhou Yijun Cao Xiaohe Liu Renzhi Ma School of Chemical Engineering Zhengzhou UniversityZhengzhou450001China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China International Center for Materials Nanoarchitectonics(WPI-MANA) National Institute for Materials Science(NIMS)Namiki 1-1TsukubaIbaraki305-0044Japan

To effectively alleviate the ever-increasing energy crisis and environmental issues,clean and sustainable energy-related materials as well as the corresponding storage/conversion devices are in urgent demand.Silicon(Si) with the second most elemental abundance on the crust in the form of silicate or silica(SiO_(2)) minerals,is an advanced emerging material showing high performance in energy-related fields(e.***.batteries,photocatalytic hydrogen evolution).For the improved performance in industry-scale applications,Si materials with delicate nanostructures and ideal compositions in a massive production are highly cherished.On account of the reserve,low cost and diverse micro-nanostructures,silicate minerals are proposed as promising raw materials.In the article,crystal structures and the reduction approaches for silicate minerals,as well as recent progress on the as-reduced Si products for clean energy storage/conversion,are presented systematically.Moreover,some cutting-edge fields involving Si materials are discussed,which may offer deep insights into the rational design of advanced Si nanostructures for extended energy-related fields.

关键词： minerals massive silicate

Corchorus olitorius: A Promising Medicinal Plant in Southern Africa and Effects of Growing Conditions on Its Bioactive Compounds—A Review

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Journal of Biosciences and Medicines 2024年第6期12卷 255-274页

作者： Senewa Bobby Pholoma Gulelat Haki Goitseone Malambane Seoleseng Tshwenyane Joseph Adjetey Crop and Soil Sciences Department Botswana University of Agriculture and Natural Resources Gaborone Botswana Food Science and Technology Department Botswana University of Agriculture and Natural Resources Gaborone Botswana

Corchorus olitorius (Jew’s mallow), is one of the African indigenous leafy vegetables increasingly getting attention as a possible contributor of both micronutrients and bioactive compounds including proteins, lipids, fiber and vitamin C to human nutrition. Leaves of Corchorus olitorius have been found to have high level of phytochemicals: flavonoids, polyphenols, tannins, and saponins that possess strong radical scavenging activity and antioxidant power. In the arid and semi-arid areas of the world, drought is the main limiting factor affecting plant productivity and influences almost all aspects of plant biology. Water stress deficit is known to cause oxidative stress condition that has generally been reported to elevate phenolic antioxidants in various crops including Jew’s mallow. On the other hand, fertilization is crucial for crop management and high yield, it also affects nutritional value of the food plants. Nitrogen (N) fertilization affects health and nutritional value, including mineral content, fatty acid profile, anti-oxidative capacity and polyphenol levels and composition. The possible effects of fertilization should be considered when deciding on fertilization regime, to optimize both plant physiology, productivity and food-related effects. Nitrogen is an important element for Jew’s mallow production since it responds well to it. However, appropriate amounts of nutrients need to be provided to crops at the right time to favor both crop growth, yield and quality. Different reports confirmed that addition or increase of N, negatively affects the total phenolics and total flavonoids, and reduces accumulation of defense-related secondary metabolites resulting in lower oxidative capacity. Increased secondary metabolite production during water deficit and low nitrogen in the soil has been reported as a stress mechanism by most plants. However, further research is required to explore the biochemical response of Jew’s mallow to water deficit and nitrogen fertilization.

关键词： Jew’s Mallow Nitrogen Antioxidants Drought minerals

Sensory and Nutritional Properties and Stability of Formulated Organic Food Flavour Enhancers

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Open Journal of Applied Sciences 2024年第6期14卷 1490-1506页

作者： Bebbe Fadimatou Bolona Bonheur Achu Mercy Bih Loh Department of Biochemistry Faculty of Science University of Yaound I Yaound Cameroon

Most food flavours have been shown to contain high quantities of cooking salt, followed by flavour enhancers such as sodium glutamate, disodium inosinate, disodium guanylate and hydrogenated oils. Excess of these substances is associated with cardiovascular diseases and neurodegenerative disorders. In an effort to reduce the harmful effects of these synthetic substances, this study therefore aimed to formulate organic, nutritious food flavours with good storage stability from less harmful locally available food ingredients. A survey was carried out in 130 households and restaurants in the city of Yaoundé Cameroon, in order to evaluate the level of consumption of industrial flavours. Certain ingredients such as prawns, onions, garlic, white peppers, gingers and salt were used in some households as organic flavours. These ingredients and others were used to prepare 5 organic flavours. Their sensory and nutritional analyses and stability to storage within 90 days were evaluated. The survey revealed that 74.6% of respondents consume industrial flavours, with the cube flavour being the most widely consumed (81%). Two of the 5 organic flavours (434 and 634) had highest scores for general acceptability. The nutritional analyses of the formulae retained (434 and 634), showed that they contained: 11.08% and 10.68% fresh weight for moisture, 47.63% and 43.53% protein, 16.52% and 13.62% lipids, 2.20% and 2.44% fibres, 11.69% and 16.39% carbohydrates. Formula 434, the most accepted, had higher contents of Ca (257.97), Mg (115.91), K (1163), Zn (2.98), Cu (1.02) and Fe (12.43 mg/100g DM) while the second (634) had higher contents of sodium (3270.48) and manganese (2.18 mg/100g). Their water activity during storage in polypropylene bags for 90 days ranged from 0.39 - 0.58 at a temperature of 26.6˚C - 37˚C. The oxidative stability (90 days), determined by the acid and peroxide indices, was 9.18 - 14.13 mg KOH/g and 1.98 - 6.46 meq O2/Kg, respectively indicating good stability for 90 days of storage. The high levels of proteins

关键词： Organic Food Flavour Monosodium Glutamate Proteins minerals Stability

Colostrum and milk performance,and blood immunity indices and minerals of Holstein cows receiving organic Mn,Zn and Cu sources

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Animal Nutrition 2020年第1期6卷 61-68页

作者： Habiballah Roshanzamir Javad Rezaei Hassan Fazaeli Department of Animal Science Faculty of AgricultureTarbiat Modares UniversityP.O.Box 14U5-336TehranIran Animal Science Research Institute of Iran Agricultural ResearchEducation and Extension Organization(AREEO)Karaj.***Iran

Effects of supplementing the basal diets with Mn,Zn and Cu,as sulphate,glycine or methionine salts,on colostrum and milk performance,some blood immunity indices and blood minerals of pre-and postpartum Holstein cows were accessed.Forty cows in different groups received:1)a diet without supplementary Mn,Zn and Cu(control),2)a diet containing Mn,Zn and Cu sulphates,3)a diet containing Mn,Zn and Cu glycine,or 4)a diet containing Mn,Zn and Cu methionine with 10 cows per group from d 60 before calving(dry period)to d 100 of lactation.Dry matter intake(DMI),dry matter digestibility(DMD),colostrum and milk performance,milk somatic cell count(SCC),blood and milk total antioxidant capacity(TAC),immunoglobulin M(IgM)and immunoglobulin A(IgA),and blood Mn,Zn and Cu were determined.Dietary supplementation with Mn,Zn and Cu as methionine,glycine or sulphate salts had positive effects on DMD,DMI,colostrum and milk performance,milk SCC,and blood Mn and Zn.Addition of Mn,Zn and Cu in diets could increase(Pminerals-supplemented groups(P>0.05),however,the blood concentrations of IgA(except d 1 postpartum)and IgM in the cows supplemented with organic Mn,Zn and Cu were higher(Pminerals.Overall,dietary supplementation of Mn,Zn and Cu as methionine,glycine or sulphate salts can improve colostrum and milk performance,blood Zn and Mn and immunity indices in Holstein cows and their new-born calves.Moreover,the organic sources of Mn,Zn and Cu have advantage over the sulphate forms in terms of the blood immunoglobulins.

关键词： Antioxidant status Cattle Immunity Organic trace minerals Performance

The effects of clay minerals and organic matter on nanoscale pores in Lower Paleozoic shale gas reservoirs, Guizhou, China

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Acta Geochimica 2018年第6期37卷 791-804页

作者： Yuantao Gu Quan Wan Wenbin Yu Xiaoxia Li Zhongbin Yu State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences School of Resource and Environment Henan University of Engineering

In organic-rich gas shales, clay minerals and organic matter(OM) have significant influences on the origin, preservation, and production of shale gas. Because of the substantial role of nanoscale pores in the generation,storage, and seepage of shale gas, we examined the effects of clay minerals and OM on nanoscale pore distribution characteristics in Lower Paleozoic shale gas reservoirs.Using the Niutitang and Longmaxi shales as examples, we determined the effects of clay minerals and OM on pores through sedimentation experiments. Field emission–scanning electron microscopy combined with low-pressure N2 adsorption of the samples before and after sedimentation showed significant differences in pore location and pore size distribution between the Niutitang and Longmaxi shales. Nanoscale pores mostly existed in OM in the Longmaxi shale and in clay minerals or OM–clay composites in the Niutitang shale. The distribution differences were attributed largely to variability in thermal evolution and tectonic development and might account for the difference in gas-bearing capacity between the Niutitang and Longmaxi reservoirs. In the nanoscale range, mesopores accounted for 61–76% of total nanoscale pore volume.Considerably developed nanoscale pores in OM were distributed in a broad size range in the Longmaxi shale, which led to good pore connectivity and gas production.Numerous narrow pores(i.e., pores \ 20 nm) in OM–clay composites were found in the Niutitang shale, and might account for this shale's poor pore connectivity and low gas production efficiency. Enhancing the connectivity of the mesopores(especially pores \ 20 nm and those developed in OM–clay composites) might be the key to improving development of the Niutitang shale. The findings provide new insight into the formation and evolutionary mechanism of nanoscale pores developed in OM and clay minerals.

关键词： Nanoscale pore Clay minerals Organic matter OM-clay composites Pore distribution characteristics Pore connectivity

Process mineralogy as a key factor affecting the flotation kinetics of copper sulfide minerals

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International Journal of minerals,Metallurgy and Materials 2019年第4期26卷 430-439页

作者： Ataallah Bahrami Mirsaleh Mirmohammadi Yousef Ghorbani Fatemeh Kazemi Morteza Abdollahi Abolfazl Danesh Department of Mining Engineering Urmia University School of Mining Engineering College of EngineeringUniversity of Tehran Department of Civil Environmental & Natural Resources EngineeringLule? University of Technology Complex of Copper Processing-Sungun

The aim of this study is to apply process mineralogy as a practical tool for further understanding and predicting the flotation kinetics of the copper sulfide minerals. The minerals' composition and association, grain distribution, and liberation within the ore samples were analyzed in the feed, concentrate, and the tailings of the flotation processes with two pulp densities of 25 wt% and 30 wt%. The major copper-bearing minerals identified by microscopic analysis of the concentrate samples included chalcopyrite(56.2 wt%), chalcocite(29.1 wt%),covellite(6.4 wt%), and bornite(4.7 wt%). Pyrite was the main sulfide gangue mineral(3.6 wt%) in the concentrates. A 95% degree of liberation with d_(80) > 80 μm was obtained for chalcopyrite as the main copper mineral in the ore sample. The recovery rate and the grade in the concentrates were enhanced with increasing chalcopyrite particle size. Chalcopyrite particles with a d_(80) of approximately 100 μm were recovered at the early stages of the flotation process. The kinetic studies showed that the kinetic second-order rectangular distribution model perfectly fit the flotation test data. Characterization of the kinetic parameters indicated that the optimum granulation distribution range for achieving a maximum flotation rate for chalcopyrite particles was between the sizes 50 and 55 μm.

关键词： microscopic analysis flotation kinetics second order rectangular distribution model sulphide minerals