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Effect of Phosphatization on Element Concentration of Cobalt-Rich Ferromanganese Crusts 被引量:10
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作者 PANJiahuax E.H.DeCARLO +2 位作者 YANGYi LIUShuqin YOUGuoqin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第3期349-355,共7页
A detailed study on a small scale of the effect of phosphatization on the chemistry of marine cobalt-rich ferromanganese crusts supplies useful information for the evaluation and comprehensive utilization of crust min... A detailed study on a small scale of the effect of phosphatization on the chemistry of marine cobalt-rich ferromanganese crusts supplies useful information for the evaluation and comprehensive utilization of crust mineral resources. Sub-samples from top to bottom of a 10-cm thick sample from the NW Pacific Magellan seamount were taken at 5 mm intervals. The concentration profiles of ore-forming and rare earth elements show that obvious differences exist between young unphosphatized crusts and old phosphatized crusts. In the old crusts Fe, Mn, Si, Al, Zn, Mg, Co, Ni and Cu elements are depleted and Ca, P, Sr, Ba and Pb elements are enriched. The order of depletion is Co > Ni > Mg > Al > Mn > Si> Cu > Zn > Fe, while the order of enrichment is P > Ca > Ba > Pb > Sr. The phosphate mineral controls the concentration variation of the ore-forming elements in crusts and causes loss of the main ore-forming elements such as Co and Ni. The phosphatization also affects the abundance of REEs in the crusts. REEs are more abundant and the content of Ce in old crusts is higher than that in young crusts, however, the pattern of REEs and their fractionation characteristics in new and old crusts are not fundamentally changed. A Y-positive anomaly in old crusts has no relationship to the phosphatization. 展开更多
关键词 phosphatization ore-forming element REE Co-rich crust concentration effect Pacific
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The distribution of iodine and effects of phosphatization on it in the ferromanganese crusts from the Mid-Pacific Ocean 被引量:2
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作者 JI Lihong LIU Guangshan +2 位作者 HUANG Yipu XING Na CHEN Zhigang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第8期13-19,共7页
In the present paper, iodine (I), iron (Fe), manganese (Mn), cobalt (Co), phosphorus (P) and calcium (Ca) contents in three ferromanganese crusts from the Pacific Ocean are measured by spectrophotometric m... In the present paper, iodine (I), iron (Fe), manganese (Mn), cobalt (Co), phosphorus (P) and calcium (Ca) contents in three ferromanganese crusts from the Pacific Ocean are measured by spectrophotometric method and inductively coupled plasma atomic emission spectrometers (ICP-AES) to investigate the contents and distribution of iodine in ferromanganese crusts. The results show that iodine contents in three crusts vary between 27.1 and 836 mg/kg, with an average of 172 mg/kg, and the profile of iodine in the three crusts all exhibits a two-stage distribution zone: a young non-phosphatized zone and an old phosphatized zone that is rich in I, P and Ca. The iodine content ratios of old to young zone in MP5D44, CXD62-1 and CXD08-1 are 2.3, 3.4 and 13.7, respectively. The boundary depths of two-stage zone in MP5D44, CXD62-1 and CXD08-1 locate at 4.0 cm, 2.5 cm and 3.75 cm, respectively, and the time of iodine mutation in three crusts ranges from 17-37 Ma derived from 129I dating and Co empirical formula, which is consistent with the times of Cenozoic phosphatization events. The present study shows that the intensity of phosphatization is the main responsible for the distribution pattern of iodine in the crusts on the basis of the correlation analysis. Consequently, iodine is a sensitive indicator for phosphatization. 展开更多
关键词 ferromanganese crust IODINE phosphatization Mid-Pacific Ocean two-stage distribution
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Secondary Phosphatization of the Earliest Cambrian Small Shelly Fossil Anabarites from Southern Shaanxi 被引量:1
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作者 Yali Chen Xuelei Chu +1 位作者 Xingliang Zhang Mingguo Zhai 《Journal of Earth Science》 SCIE CAS CSCD 2016年第2期196-203,共8页
Biomineralization may have an extremely long evolutionary history since the Paleoarchean, while the widespread biomineralization among metazoan lineages started at the earliest Cambrian. However, the primary mineralog... Biomineralization may have an extremely long evolutionary history since the Paleoarchean, while the widespread biomineralization among metazoan lineages started at the earliest Cambrian. However, the primary mineralogy of Anabarites shell remains controversial. Optical microscopic observations combined with the Back-Scattered Electron(BSE) and Energy-Dispersive X-ray Spectroscopy(EDS) analyses are used to study the shell of the fossil Anabarites from the Kuanchuanpu fauna in southern Shaanxi Province in China, which is correlated to the Cambrian Fortunian Stage. The EDS analysis shows that the phosphorus-rich layer closely adjacent to the calcified layer exhibits a Ca: P: C ratio compositionally similar to the mineral fluorapatite(Ca_5(PO_4,CO_3)_3(F,CO_3). The result that the calcified layer and the phosphorus-rich layer have different chemical compositions is consistent with the optical observation that there is an obvious gap between these two layers and the phosphorus-rich layer can extend to the phosphatic material inside of the tube, suggesting the phosphorus-rich layer doesn't belong to the original shell. We suggest that the phosphorous-rich layer is diagenetic in origin, precipitated as a result of phosphorus release during the decay of organic matter by microbes. Considering the outermost shell layer(OMS, biologically controlled carbonate shell layer) should display different isotopic information from the carbonate matrix(i.e., OMS is ^(12)C concentrated due to the biogenic organic matter template is readily rich in ^(12)C), Nano SIMS was used to map ion distributions of C and N in the shell of Anabarites and matrix. However, ion images show that the concentration differences of ^(12)C, ^(13)C and ^(26)CN among the OMS and the matrix are unclear, while ^(12)C and ^(26)CN are supposed to be enriched in the OMS. Therefore, the minor isotopic differences between the shell and the matrix is hard to be detected by Nano SIMS, at least in our sample, probably due to alteration of the ^(12)C-rich characteristic of the Anabarites OMS during the late diagenesis. 展开更多
关键词 BIOMINERALIZATION Anabarites Fortunian Stage phosphatization NANOSIMS southernShaanxi.
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Effect of rare earth on the coating-forming and mechanism of phosphatization 被引量:4
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作者 邝钜炽 黄莺 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第S1期132-135,共4页
It was ascertained that when a RE element was added in bath,the sample was improved on the anti-corrosion power of the coating because of the increasing of covering rate of formless crystal Zn2Fe(PO4) 2·4H2O(mark... It was ascertained that when a RE element was added in bath,the sample was improved on the anti-corrosion power of the coating because of the increasing of covering rate of formless crystal Zn2Fe(PO4) 2·4H2O(marked P) crystals and the ratio of P/(P+H) (H was the mark of Zn3(PO4) 2 crystal) in the coating,combination of which with components parsing by EDS indicated that the sequence of contribution elements P and Zn to erosion resistance of coatings was P】Zn. And the correlative mechanism was discussed,which made it clear that owing to the particularity of the outer-shell electron structure and larger ionic radius,RE was so easy to be polarized and metamorphosed itself that it adsorbed lightly on the basic body to pose gels. They efficiently reduced the activation energy which was required for formation of a new solid phase of phosphates and made it also possible to engender effectively active nucleation regions of cathode and anode under low temperature phosphating condition,which was propitious to formation,densification and uniformization of the phosphate crystal nucleus and growth of the crystallite and coating buildup. Thus it could be seen that REN played the role of surface regulator and accelerant,which speeded up the phosphating,as well as bids amount of porosity of the coating fall to improve the corrosion resistance of the coating. 展开更多
关键词 rare earths (RE) phosphate coating configuration analysis DEPOLARIZATION NUCLEATION
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Preservation potential of Cambrian small shelly fossils in different microfacies, North China
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作者 Yazhou Hu Timothy P。Topper +7 位作者 Luke C。Strotz Yue Liang Fan Liu Rao Fu Baopeng Song Zhao Wang Bing Pan Zhifei Zhang 《Geoscience Frontiers》 2025年第5期139-165,共27页
Small shelly fossils(SSFs)have long been recognized as important to the studies of both metazoan evolution and the onset of biomineralization during the Cambrian radiation.The marked decline in the occurrence,diversit... Small shelly fossils(SSFs)have long been recognized as important to the studies of both metazoan evolution and the onset of biomineralization during the Cambrian radiation.The marked decline in the occurrence,diversity and abundance of SSFs in the middle to late Cambrian,when compared with the early Cambrian,has often been regarded as a result of the closure of a phosphatization window.Despite this,there have been numerous and consistent reports of SSFs from the middle Cambrian and younger deposits.To identify possible factors influencing SSF preservation,five microfacies including bioclastic limestone,flat-pebble conglomerates with bioclasts,hummocky cross-stratified grainstone with bioclasts,bioclastic grainstone in hardgrounds and glauconite bioclastic wackstone-packstone,from Cambrian Series 2 to Miaolingian in North China are compared to assess how differences in lithology impact the preservation potential of SSFs.Our results,based on 35,161 SSF specimens from deposits across six sections,suggest that there are still abundant and diverse SSFs in the middle Cambrian of North China preserved in ways not exclusively reliant on the presence of phosphate and that SSF preservation can be linked to the differences in microfacies in the early to middle Cambrian of North China. 展开更多
关键词 Small shelly fossils Shell structure GLAUCONITE phosphatization window
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Flash-PEO of magnesium:Phosphate precursor driven functionalization 被引量:2
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作者 M.H.Guerra-Mutis J.M.Vega +2 位作者 M.I.Barrena E.Matykina R.Arrabal 《Journal of Magnesium and Alloys》 2025年第2期592-612,共21页
In this study,a phosphate-based conversion coating(PCC)was applied as a precursor before forming silicate-fluoride(SiF)and silicate-phosphate-fluoride(SiPF)based flash-plasma electrolytic oxidation(Flash-PEO)coatings ... In this study,a phosphate-based conversion coating(PCC)was applied as a precursor before forming silicate-fluoride(SiF)and silicate-phosphate-fluoride(SiPF)based flash-plasma electrolytic oxidation(Flash-PEO)coatings on AZ31B magnesium alloy.The main novelty is the successful incorporation of calcium,zinc,manganese and phosphate species into the Flash-PEO coatings via a precursor layer rather than using the electrolyte.The precursor also led to longer lasting and more intense discharges during the PEO process,resulting in increased pore size.Corrosion studies revealed similar short-term performance for all coatings,with impedance modulus at low frequencies above 10^(7)Ωcm^(2),and slightly better performance for the SiPF-based coating.Nonetheless,the enlarged pores in the PEO coatings functionalized with the PCC precursor compromised the effectiveness of self-healing mechanisms by creating diffusion pathways for corrosive species,leading to earlier failure.These phenomena were effectively monitored by recording the open circuit potential during immersion in 0.5 wt.%NaCl solution.In summary,this study demonstrates that conversion coatings are a viable option for the functionalization of PEO coatings on magnesium alloys,as they allow for the incorporation of cationic and other species.However,it is crucial to maintain a small pore size to facilitate effective blockage through self-healing mechanisms. 展开更多
关键词 AZ31B magnesium alloy PHOSPHATES Chemical conversion coating Flash plasma electrolytic oxidation Electrochemical impedance spectroscopy Transmission electron microscopy
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Phosphorus acquisition by plants:Challenges and promising strategies for sustainable agriculture in the 21st century 被引量:1
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作者 Tamara GÓMEZ-GALLEGO Iván SÁNCHEZ-CASTRO +4 位作者 Lázaro MOLINA Carmen TRASAR-CEPEDA Carlos GARCÍA-IZQUIERDO Juan L.RAMOS Ana SEGURA 《Pedosphere》 2025年第1期193-215,共23页
Whilst phosphorus(P)in soil is considered to be abundant,the portion available for plant uptake constitutes less than 1%of the overall P present.To enhance crop productivity,the utilization of mineral P fertilizers ha... Whilst phosphorus(P)in soil is considered to be abundant,the portion available for plant uptake constitutes less than 1%of the overall P present.To enhance crop productivity,the utilization of mineral P fertilizers has become pervasive in agriculture.Nonetheless,the escalating prices of chemical fertilizers,coupled with new European regulations prohibiting the use of P fertilizers containing cadmium,have highlighted the urgency to identify environmentally friendly products and practices for P fertilization in agricultural soils.This comprehensive review delves into the current landscape of P fertilization from agricultural,political,and economic standpoints.We recognize the potential of microbes in mobilizing P,but emphasize the necessity for more robust research to establish their effectiveness in promoting plant P uptake under real-world conditions.Additionally,we explore the role of agricultural conservation practices,such as optimal tillage,diversified cropping systems,and increased organic carbon input,in conserving P.Furthermore,this review contemplates forthcoming innovations in research.These innovations encompass the development of enhanced formulations for biofertilizers and the undertaking of more comprehensive studies within the realm of conservation agriculture.All these endeavors collectively hold the potential to augment P accessibility to plants in a sustainable manner,thereby advancing agricultural sustainability and productivity. 展开更多
关键词 BIOFERTILIZER conservation agriculture cropping system organic fertilization phosphate-solubilizing microorganism phosphorus availability rock phosphate
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High-energy-density lithium manganese iron phosphate for lithium-ion batteries:Progresses,challenges,and prospects 被引量:1
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作者 Bokun Zhang Xiaoyun Wang +5 位作者 Shuai Wang Yan Li Libo Chen Handong Jiao Zhijing Yu Jiguo Tu 《Journal of Energy Chemistry》 2025年第1期1-17,共17页
The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion batteries.Lithium manganese iron phosphate(LiMn_(x)Fe_(1-x)PO_(4))has garnered... The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion batteries.Lithium manganese iron phosphate(LiMn_(x)Fe_(1-x)PO_(4))has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy density.Although LiMn_(x)Fe_(1-x)PO_(4)has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap density.This review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMn_(x)Fe_(1-x)PO_(4)to analyze reaction processes accurately and guide material preparation.Later,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMn_(x)Fe_(1-x)PO_(4),including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology design.Finally,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are anticipated.More importantly,it is expected to provide key insights into the development of high-performance and stable LiMn_(x)Fe_(1-x)PO_(4)materials,to achieve practical energy storage requirements. 展开更多
关键词 Lithiummanganese iron phosphate High energydensity LITHIUM-IONBATTERIES Reactionmechanism Tap density
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Green and High-Yield Recovery of Phosphorus from Municipal Wastewater for LiFePO_(4)Batteries 被引量:1
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作者 Yijiao Chang Xuan Wang +6 位作者 Bolin Zhao Anjie Li Yiru Wu Bohua Wen Bing Li Xiao-Yan Li Lin Lin 《Engineering》 2025年第2期234-242,共9页
The rapidly growing demand for lithium iron phosphate(LiFePO_(4))as the cathode material of lithium-ion batteries(LIBs)has aggravated the scarcity of phosphorus(P)reserves on Earth.This study introduces an environment... The rapidly growing demand for lithium iron phosphate(LiFePO_(4))as the cathode material of lithium-ion batteries(LIBs)has aggravated the scarcity of phosphorus(P)reserves on Earth.This study introduces an environmentally friendly and economical method of P recovery from municipal wastewater,providing the P source for LiFePO_(4) cathodes.The novel approach utilizes the sludge of Fe-coagulant-based chemical P removal(CPR)in wastewater treatment.After a sintering treatment with acid washing,the CPR sludge,enriched with P and Fe,transforms into purified P-Fe oxides(Fe2.1P1.0O5.6).These oxides can substitute up to 35%of the FePO_(4) reagent as precursor,producing a carbon-coated LiFePO_(4)(LiFePO_(4)/C)cathode with a specific discharge capacity of 114.9 mA·h·g^(-1)at current density of 17 mA·g^(-1)),and cycle stability of 99.2%after 100 cycles.The enhanced cycle performance of the as-prepared LiFePO_(4)/C cathode may be attributed to the incorporations of impurities(such as Ca^(2+)and Na^(+))from sludge,with improved stability of crystal structure.Unlike conventional P-fertilizers,this P recovery technology converts 100%of P in CPR sludge into the production of value-added LiFePO_(4)/C cathodes.The recovered P from municipal wastewater can meet up to 35%of the P demand in the Chinese LIBs industry,offering a cost-effective solution for addressing the pressing challenges of P scarcity. 展开更多
关键词 Municipal wastewater Chemical phosphorus removal sludge Lithium iron phosphate Lithium-ion batteries Phosphorus recovery
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A Novel Injectable KGM/Fiber Composite Bone Cement for Bone Defect
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作者 LIU Hanwu ZHAO Qiang +1 位作者 XIAO Ting YAN Tingting 《材料导报》 北大核心 2025年第19期254-261,共8页
The injection of bone cement is a promising surgical intervention for the treatment of osteoporosis.The aim of this study was to formulate a novel injectable bioactive bone cement to adress such medical problems.The b... The injection of bone cement is a promising surgical intervention for the treatment of osteoporosis.The aim of this study was to formulate a novel injectable bioactive bone cement to adress such medical problems.The bone cement primarily consists of tricalcium phosphate(β-TCP),konjac glucomannan(KGM),and hydroxyapatite whisker(HAw).An orthogonal experiment was designed to generate multiple sets of new composite calcium phosphate cement(NCPC)samples,and their setting times were measured.The in vitro compatibility of the new bone cement was assessed through relative cell proliferation rate(RGR)and in vitro cell growth experiments.Mechanical strength and porosity tests were conducted for each group of bone cement,and cross-sectional morphology was observed.The results demonstrate that the bone cement exhibits favorable properties such as self-curing,mechanical robustness,and resistance to collapse.The optimum formulation involves a doping ratio of 5/15(wt%)HAw and HA,an additional amount of 1.2wt%KGM,and a liquid citric acid concentration of 2wt%.Porosity tests confirmed that the material has high compressive strength and a favorable porosity of 27%,creating conducive conditions for cell growth,proliferation,and material degradation.Moreover,in vitro cell culture experiments revealed excellent biocompatibility of the material.Consequently,the developed NCPC emerges as a potential candidate material for applications of bone implantation. 展开更多
关键词 bone cement calcium phosphate orthogonal test setting time konjac glucomannan
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Critical roles of AlPO_(4) coating in enhancing cycling stability and rate capability of high voltage LiNi_(0.5)Mn_(1.5)O_(4) cathode materials
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作者 WU Jie LUO Zhihong +6 位作者 CHEN Xiaoli XIONG Fangfang CHEN Li ZHANG Biao SHI Bin OUYANG Quansheng SHAO Jiaojing 《无机化学学报》 北大核心 2025年第5期948-958,共11页
LiNi_(0.5)Mn_(1.5)O_4(LNMO) was prepared by a high-temperature solid phase method,and then Al PO_(4)(AP) was coated on the polyhedral LNMO surface by the wet chemical method.The experimental results showed that the LN... LiNi_(0.5)Mn_(1.5)O_4(LNMO) was prepared by a high-temperature solid phase method,and then Al PO_(4)(AP) was coated on the polyhedral LNMO surface by the wet chemical method.The experimental results showed that the LNMO-1%AP|Li cell prepared with a 1%mass ratio of Al PO_(4and) LNMO had better electrochemical performance;after 450 cycles at 1C,its discharge specific capacity maintained 108.78 m Ah·g^(-1),while that of the LNMO|Li cell was only 86.04 m Ah·g^(-1).Especially at the high rates of 5C and 10C,the electrochemical properties of the former were far superior to the latter.This was attributed to the fact that the AP coating made the surface of LNMO in contact with the electrolyte more stable,effectively promoted the Li~+transport,and reduced the polarization voltage of the electrode. 展开更多
关键词 LiNi_(0.5)Mn_(1.5)O_(4) high voltage lithium‑ion batteries high‑temperature solid‑phase method aluminum phosphate
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Determination of main influence mechanism of fulvic acid on arsenic removal by ferric chloride
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作者 Xiaoguang Meng Sihang Xu +6 位作者 Meng Ji Qiantao Shi Biswarup Guha Kelly Mascarenhas Lee Lippincott Wen Zhang Qingquan Ma 《Journal of Environmental Sciences》 2025年第7期22-29,共8页
In this study,synthetic wastewater containing 110μg/L arsenate(As(V)),0-20 mg/L fulvic acid(FA),and 0-12.3 mg/L phosphate was treated with 3 mg/L Fe3+.The mechanisms of FA and phosphate effects on As(V)removal by fer... In this study,synthetic wastewater containing 110μg/L arsenate(As(V)),0-20 mg/L fulvic acid(FA),and 0-12.3 mg/L phosphate was treated with 3 mg/L Fe3+.The mechanisms of FA and phosphate effects on As(V)removal by ferric chloride were determined using 0.22-10μm pore-size filtration,Zetasizer analysis,and in situ flow through cell ATR-FTIR.The results showed that up to 20mg/L FA had almost no effect on the solubility of ferric hydroxide precipitates and adsorption of As(V)by the precipitates.When FA concentration increased from 0 to 20 mg/L,the adsorption of FA led to higher negative zeta potential of the precipitates and the strong electrostatic repulsion between the precipitates decreased the particle size of ferric hydroxide flocs fromlarger than 10μmto smaller than 1μm.In the presence of 5-20 mg/L FA,46%-63%As(V)was adsorbed onto the flocs with particle size in the range of 0.45-1μm.On the other hand,phosphate did not affect the size of ferric hydroxide flocs and significantly increased the dissolved As(V)concentration because it competed with As(V)for adsorption sites on ferric hydroxide precipitates.The addition of 5mg/L cationic organic flocculant significantly reduced the effect of FA on As(V)removal,but did not reduce the effect of phosphate on As(V)removal.The findings of this study will help develop effective arsenic treatment techniques and predict the mobility of arsenic in the environment. 展开更多
关键词 ARSENIC Fulvic acid PHOSPHATE COAGULATION Adsorption Ferric chloride FILTRATION CENTRIFUGATION
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Nutrient-mediated changes in growth,biochemical composition,and biosilica deposition in Cyclotella cryptica
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作者 Yuting YU Yan SUN +6 位作者 Yuhang LI Zhengfeng ZHU Lin ZHANG Jian LI Spiros NAGATHOS Chengxu ZHOU Jichang HAN 《Journal of Oceanology and Limnology》 2025年第5期1567-1586,共20页
Cyclotella cryptica,a model diatom known for its robust adaptability to variable salinity and temperature conditions,is a promising candidate for large-scale biotechnological applications.Nutrient availability,particu... Cyclotella cryptica,a model diatom known for its robust adaptability to variable salinity and temperature conditions,is a promising candidate for large-scale biotechnological applications.Nutrient availability,particularly nitrogen and phosphorus,plays a crucial role in the metabolic activities of microalgae,influencing its industrial utility.Exploring the relationship between these essential nutrients and both the yield and biochemical composition of this microalga is crucial for optimizing cultivation strategies.However,research focusing on the effects of nitrogen and phosphorus on C.cryptica remains limited.We investigated the impacts of varying concentrations of nitrate(0.25-3.96 mmol/L)and phosphate(14.4-229.6μmol/L)on C.cryptica culture by analyzing its growth performance,photosynthetic activity,biochemical composition,and biosilica deposition.Results indicate that C.cryptica exhibited enhanced growth,photosynthetic efficiency,and carotenoid production under higher nutrient concentrations.However,the effects of nitrate on macronutrients composition and fatty acids profile differed from those of phosphate.Specifically,increased nitrate levels resulted in higher concentrations of polyunsaturated fatty acids(PUFAs)at the expense of saturated fatty acids(SFAs),while increased phosphate levels were associated with increased PUFAs and reduced monounsaturated fatty acids(MUFAs).Additionally,biosilica deposition was weakened by elevated nitrate but enhanced by increased phosphate levels.This study improved our understanding of nutrient-mediated regulatory mechanisms in diatoms and contributed valuable data to the broader field of algal biotechnology.Moreover,these findings are expected to advance the development of tailored nutrient management strategies,thereby enhancing the industrial potential of C.cryptica. 展开更多
关键词 Cyclotella cryptica NITRATE PHOSPHATE FUCOXANTHIN frustule
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Effect of slow-release phosphate on stabilization and long-term stability of Zn and Cd in soil
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作者 Chu-xuan LI Shan-xin YUAN +7 位作者 Hai-feng LI Yong-ping LU Wei-chun YANG Wen-shun KE Lu TANG Chong-jian TANG William HARTLEY Sheng-guo XUE 《Transactions of Nonferrous Metals Society of China》 2025年第6期2091-2104,共14页
Slow-release phosphate materials were prepared by activating insoluble phosphate with organic acid to stabilize high concentrations of Cd and Zn in contaminated smelter soil.The results showed that oxalic acid(0.1 mol... Slow-release phosphate materials were prepared by activating insoluble phosphate with organic acid to stabilize high concentrations of Cd and Zn in contaminated smelter soil.The results showed that oxalic acid(0.1 mol/L)activated tricalcium phosphate(TO-0.1)provided the most efficient stabilization of Cd and Zn.After 30 d treatment,leaching concentrations of Cd and Zn in soil were decreased from 3.17 and 16.60 mg/L to 0.078 and 0.32 mg/L,respectively.The acid-soluble fractions of Cd and Zn were transformed into reducible,oxidizable,and residual fractions.Notably,As mobility in TO-0.1 treated soils did not increase.In addition,acid rain leaching and 150 d of natural aging revealed that the slow-release phosphate material provided long-term stability for the stabilization of Cd and Zn.This study verifies the potential application of slow-release phosphate materials for the remediation of heavy metal contaminated soil at smelting sites. 展开更多
关键词 smelting sites ZN CD PHOSPHATE slow-release long-term stability
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Biodegradation and biocompatibility of calcium phosphate-coated magnesium in eye environment,in vitro and in vivo
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作者 Yi Chen Yi Lin +8 位作者 Wangdu Luo Huanhuan Gao Yaobo Hu Liying Qiao Jia She Lin Xie Xiangji Li Yong Wang Fusheng Pan 《Journal of Magnesium and Alloys》 2025年第7期3081-3095,共15页
The possible application of magnesium(Mg)in glaucoma surgical treatment has been investigated in our previous work.In this paper,the degradation behavior and biocompatibility of Mg coated with hydroxyapatite(HA)and di... The possible application of magnesium(Mg)in glaucoma surgical treatment has been investigated in our previous work.In this paper,the degradation behavior and biocompatibility of Mg coated with hydroxyapatite(HA)and dicalcium phosphate dihydrate(DCPD)in eye environment were evaluated,and uncoated Mg was used for comparison.It was found that uniform corrosion occurred macroscopically to the coated Mg samples in sodium lactate ringer’s injection(SLRI)as well as in the rabbit eyes.In micro-scale,the corrosion was characterized by local cracking and pitting primarily.Mg and calcium(Ca)were incorporated into the surface corrosion products and a multi-layer structure was formed.Compared to other samples,HA-coated Mg slowed down dramatically the alkalinity of the solution and the ion release of the sample,and exhibited the lowest corrosion rate in SLRI,which was about 0.22 mm/a.In terms of biocompatibility,fibroblasts demonstrated high viability in the HA-coated and DCPD-coated Mg groups(p<0.05)in vitro.In vivo,HA-coated Mg was found to show lower inflammatory response and fibrosis than the other groups did,as indicated by hematoxylin-eosin and immunofluorescence staining.During the degrading process of HA-coated Mg in the rabbits’eyes,no inflammation was found in the anterior chamber,lens,and vitreous body.HA-coated Mg was fully biodegraded fifteen weeks post-operation,and the scleral drainage channel(SDC)was formed without obvious scarring.It is concluded that HA-coated Mg implantation is a promising adjunctive procedure to improve the success rate of trabeculectomy.Statement of significance:Magnesium(Mg)has shown to be a potential biomaterial for ophthalmic implants in our previous work.However,inflammatory response resulted from the low corrosion resistance of Mg is a major concern.It is shown here that Mg coated with different calcium phosphates can improve these properties in varying degrees and keep the scleral drainage channel unobstructed and unscarred.Based on our in vitro and in vivo studies,HA-coated Mg exhibited a better degradation behavior and excellent biocompatibility.The scleral drainage channel still exists and aqueous humor flows out smoothly after the full degradation of the implant.It is concluded that HA-coated Mg is a promising biomaterial to increase the therapeutic efficiency of trabeculectomy for glaucoma. 展开更多
关键词 MAGNESIUM Calcium phosphate coating BIODEGRADATION BIOCOMPATIBILITY GLAUCOMA
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Phosphorite deposits:A promising unconventional resource for rare earth elements
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作者 Shamim A.Dar V.Balaram +3 位作者 Parijat Roy Akhtar R.Mir Mohammad Javed M.Siva Teja 《Geoscience Frontiers》 2025年第3期59-80,共22页
The green energy transition relies heavily on critical metals,such as rare earth elements(REEs).However,their reserves are primarily focused in a few countries,such as China,which accounts for approximately 70%of glob... The green energy transition relies heavily on critical metals,such as rare earth elements(REEs).However,their reserves are primarily focused in a few countries,such as China,which accounts for approximately 70%of global production.Hence,several countries are currently looking for alternative resources for REEs.Alternative REE resources in the supply chain include recycling of e-waste,industrial waste like red mud and phosphogypsum,coal ash,mine tailings,ocean floor sediments,and even certain types of sedimentary deposits like phosphorites where REEs are present in lower concentrations but at larger volumes compared to primary ore deposits which are becoming targets by REEs industry.Currently,several studies are going on the development of eco-friendly REEs extraction technologies from phosphorite deposits.Consequently,advanced data analysis tools,such as Machine Learning(ML),are becoming increasingly important in mineral prospectivity and are rapidly gaining traction in the earth sciences.Phosphorite deposits are mainly used to manufacture fertilizers as these rocks are known for their significant phosphorus content.Moreover,these formations are considered a prospective resource of REEs.The different types of phosphorite deposits such as continental,seamount,and ore deposits worldwide reported concentrations of∑REE upto 18,000µg/g.Due to the augmented claim of REEs for various ultra-modern,and green technology applications that are required to switch over to a carbon-neutral environment,these phosphorite deposits have become an important target mostly because of their relatively higher content of REEs especially heavy rare earth elements(HREE).For example,Mississippian phosphorites reported ∑ HREE 7,000µg/g.To have a comprehensive understanding of the REEs potential of these phosphorite deposits which also include several Chinese phosphorite deposits,this study is undertaken to review the phosphorite deposits in the world and their REEs potential,in addition to some of the associated aspects such as applications and formation mechanisms for different types of phosphorite deposits such as igneous phosphate deposits,sedimentary phosphorite deposits,marine phosphorite deposits,cave phosphate deposits,and insular guano deposits.Other important aspects include their occurrences,types,geochemical characteristics,the REEs enrichment mechanisms,and various recovery methods adopted to recover REEs from different phosphorite deposits.The present review paper concludes that the recent studies highlight the global potential of phosphorite deposits to satisfy the increasing demand for REEs.Extracting REEs from phosphorite presents no significant technological or environmental difficulties,as long as radioactive elements are eliminated.In India,more comprehensive geological surveys,along with the advancement of new methods and evaluations,are required to locate phosphorite deposits with high concentrations of REEs. 展开更多
关键词 Phosphorite deposits Phosphate phases REE BIOLEACHING Extraction Recovery
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Evaluating the Interaction of Mycorrhizal Fungi, Azotobacter, and Biochar in Enhancing Cucumber Productivity and Soil Health
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作者 Noor A.J.K.Al-Silmawy Nasser Fahim Yasir +1 位作者 Zahraa K.K.Al-Salihi Asmaa Hussein Allawi Al-Dulaimi 《Journal of Environmental & Earth Sciences》 2025年第1期103-112,共10页
This experiment evaluated the effects of the mycorrhizal fungus Glomus mosseae,Azotobacter chroococcum bacteria,and Biochar on the characteristics of the root system,and yield of the cucumber plant,Cucumis sativus L.,... This experiment evaluated the effects of the mycorrhizal fungus Glomus mosseae,Azotobacter chroococcum bacteria,and Biochar on the characteristics of the root system,and yield of the cucumber plant,Cucumis sativus L.,for this purpose,experiment designed:the first factor is a combination of Mycorrhizae(M)at 35 g plant-1,Azotobacter(A)15 ml plant-1 with a microbial density of 2.2,and three concentrations(0,5,10%)of Biochar sprayed on the plant.The results of the research demonstrated that using mycorrhizae,Azotobacter bacteria,and phosphate rock with half the mineral recommendation(MAR)and spraying Biochar at a concentration of 10%gave the highest rate of infection of the roots with mycorrhizae,amounting to 80%,and the highest dry weight of the root system reached 84.53 g.The highest number of total bacteria was 8.74 log Cfu g m-1 of soil,the highest plant height reached 375.0 cm,the highest dry weight of the shoot reached 101.66 g plant-1,and the highest yield for the greenhouse was 4.501 ton greenhouse-1,followed by the treatment of adding Mycorrhiza with phosphate rock and half the mineral recommendation(MR)with Biochar at a concentration of 10%,then treatment with the addition of mycorrhizae with Azotobacter bacteria with half the mineral recommendation(AR)with 10%of Biochar.It is possible to eliminate half of the mineral recommendation by using these fertilizers,reduce the harmful impact of pollution on the environment and enhance sustainability in agriculture. 展开更多
关键词 BIOCHAR Phosphate Rock AZOTOBACTER MYCORRHIZAL Mineral Fertilizer
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Isolation and Identification of the Plant Growth-Promoting Bacterium Pseudomonas fluorescens by 16S rRNA Sequence Analysis Its Efficacy as a Bioinoculator
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作者 Naseer Jawad Kadhim Jawad Abdul Kadhim Kamal 《Research in Ecology》 2025年第2期83-92,共10页
The isolation of bacteria from the rhizosphere soil of different plants and locations in Diwaniyah Governorate and their diagnosis by two methods.Isolation and routine molecular diagnosis revealed ten bacterial isolat... The isolation of bacteria from the rhizosphere soil of different plants and locations in Diwaniyah Governorate and their diagnosis by two methods.Isolation and routine molecular diagnosis revealed ten bacterial isolates with the attributes of P.fluorescens out of fifteen local isolates that are represented by the following codes and sequences(P.f9,P.f8,P.f6,P.f5,P.f4,P.f2,P.f1,P.f14,P.f13,P.f11).Results also confirmed the diagnosis of bacterial isolates by biochemical and molecular tests using a specialized primer to amplify the bp698 region of the 16S ribosomal RNA gene,approved by Macrogen/Korea.The test efficiency in dissolving solid phosphate by P.fluorescens bacteria showed that the most effective is the(P.f1)isolate,giving the highest score effectiveness in mineral phosphate dissolution by the diameter of the clear zone around the colony,which was effective in phosphate dissolution up to 6.95 mm.The efficiency of the Nitrogen Fixation Test showed that the isolate(P.f5)scored the highest nitrogen-fixing efficiency amount with a value of 6.81 mg L^(-1).The quantitative amount of the hormone for each of Auxins,Cytokinins,and Gibberellins was assayed;the results with isolate(P.f1)for IAA(Auxins)gave a concentration up to 28.6μg ml^(-1),which was the most,while the production of GA3 by isolate(P.f1)gave the maximum value of 36.7μg ml^(-1),and for synthesis of the hormone of Cytokinins represented by isolate(P.f2),the highest value in the production of Cytokinins hormone was recorded at 26.3μg ml^(-1). 展开更多
关键词 Pseudomonas fluorescens PCR Phosphate Dissolution Nitrogen Fixation HORMONES
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Focus on the catalysts to resist the phosphate poisoning in high-temperature proton exchange membrane fuel cells
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作者 Liyuan Gong Li Tao +2 位作者 Lei Wang Xian-Zhu Fu Shuangyin Wang 《Chinese Journal of Catalysis》 2025年第1期155-176,共22页
Investigating highly effective electrocatalysts for high-temperature proton exchange membrane fuel cells(HT-PEMFC)requires the resistance to phosphate acid(PA)poisoning at cathodic oxygen reduction reaction(ORR).Recen... Investigating highly effective electrocatalysts for high-temperature proton exchange membrane fuel cells(HT-PEMFC)requires the resistance to phosphate acid(PA)poisoning at cathodic oxygen reduction reaction(ORR).Recent advancements in catalysts have focused on alleviating phosphoric anion adsorption on Pt-based catalysts with modified electronic structure or catalytic interface and developing Fe-N-C based catalysts with immunity of PA poisoning.Fe-N-C-based catalysts have emerged as promising alternatives to Pt-based catalysts,offering significant potential to overcome the characteristic adsorption of phosphate anion on Pt.An overview of these developments provides insights into catalytic mechanisms and facilitates the design of more efficient catalysts.This review begins with an exploration of basic poisoning principles,followed by a critical summary of characterization techniques employed to identified the underlying mechanism of poisoning effect.Attention is then directed to endeavors aimed at enhancing the HT-PEMFC performance by well-designed catalysts.Finally,the opportunities and challenges in developing the anti-PA poisoning strategy and practical HT-PEMFC is discussed.Through these discussions,a comprehensive understanding of PA-poisoning bottlenecks and inspire future research directions is aim to provided. 展开更多
关键词 Fuel cell High-temperature Phosphate acid poisoning Activitydegradation Electrocatalystdesign
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Iron sulfide mineral/polylactic acid mixotrophic biofilter for simultaneous nitrate and phosphate removal
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作者 Yuwei Zhang Xueyu Liu +6 位作者 Shiyang Wang Rong A Shujie Qian Yaquan Liang Yonglan Tian Dongyang Wei Huayong Zhang 《Journal of Environmental Sciences》 2025年第10期56-67,共12页
Heterotrophic denitrification based on polylactic acid(PLAHD)can remove nitrate effectively,but it is expensive and can't remove phosphate.Autotrophic denitrification based on iron sulfide(ISAD)can simultaneously ... Heterotrophic denitrification based on polylactic acid(PLAHD)can remove nitrate effectively,but it is expensive and can't remove phosphate.Autotrophic denitrification based on iron sulfide(ISAD)can simultaneously remove nitrate and phosphate cost-effectively,but its nitrate rate is slow.So,iron sulfide mineral/polylactic acid mixotrophic biofilter(ISPLAB)was constructed to combine advantages of ISAD and PLAHD.ISPLAB achieved nitrogen and phosphorus removal rates of 98.04%and 94.12%,respectively,at a hydraulic retention time(HRT)of 24 h.The study also revealed that controlling molecular weight(MW)of PLA improved the release of soluble organic matter;adding iron sulfide enhanced the hydrolysis of PLA and precipitated PO_(4)^(3-) of Fe^(2+)/Fe^(3+),thereby facilitated simultaneous nitrogen and phosphorus removal.Microbial community analysis resulted that denitrifying bacterias(Phaeodactylibacter and Methylotenera),sulfur-reducing bacterias(Hyphomicrobium),sulfur-oxidizing bacteria(Denitratisoma),iron-reducing bacteria(Romboutsia)and hydrolyzed bacterias(norank_f_norank_o_1-20 and norank_f_Caldilineaceae)coexisted in the ISPLAB system.Organics and iron sulfide drived the denitrification process in ISPLAB. 展开更多
关键词 PLA FES Nutrient pollution Mixotrophic denitrification Simultaneous nitrate and phosphate removal
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