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A new approach to zinc–nickel separation using solution alkalinization method:application to a zinc plant residue
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作者 Mostafa Aghazadeh Ghomi Javad Moghaddam Naghi Parvini Ahmadi 《Rare Metals》 SCIE EI CAS CSCD 2020年第11期1341-1347,共7页
The present investigation involves the separation of zinc and nickel from a sulfate solution using the acidic leaching of zinc plant residue after cadmium removal step as precursor(42.88 wt%Zn,8.50 wt%Cd and 2.33 wt%N... The present investigation involves the separation of zinc and nickel from a sulfate solution using the acidic leaching of zinc plant residue after cadmium removal step as precursor(42.88 wt%Zn,8.50 wt%Cd and 2.33 wt%Ni).Separation of nickel from the solution was done by pouring it into a strong alkaline sodium hydroxide solution due to precipitation of nickel hydroxide and conversion of zinc to the soluble Zn(OH)_(4)^(2-)complex.Higher degrees of separation were reached by pouring more diluted solutions into the stronger alkaline media.To clear pursue of the process,design of experimental methodology was applied for experiments.Scrutinizing different washing steps on nickel-rich precipitates shows that the washing process decreases zinc content and thereby increases overall selectivity coefficient.Outcomes show that,at the optimized condition,Ni/Zn weight ratio in the solid product becomes about 104 times higher than the initial ratio in the initial feed solution and a nickel concentrate with 29.98 wt%Ni and 5.99 wt%Zn is achieved.At the same time,the chemical analysis of filtrate shows only 4.4 mg·L^(-1)Ni in the alkaline zinc solution,which means that over 99%nickel is recovered.The study on changes of zinc concentration with time shows that the process could be completed only after few minutes. 展开更多
关键词 ZINC NICKEL PRECIPITATION SEPARATION alkalinization
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Berberrubine-mediated pH indicator response enhances the efficacy of hydroxycamptothecin by reversing lysosomal drug resistance
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作者 Daili Liu Changxiang Yu +5 位作者 Liyuan Lin Zhidong Liu Guiqian Fang Qingqiang Yao Qixin Chen Xintian Shao 《Chinese Chemical Letters》 2025年第9期429-433,共5页
Drug resistance poses a significant challenge to effective long-term treatment across various medical fields.This study proposed a feasible strategy to enhance lysosomal alkalinization by transporting mitochondria-tar... Drug resistance poses a significant challenge to effective long-term treatment across various medical fields.This study proposed a feasible strategy to enhance lysosomal alkalinization by transporting mitochondria-targeting quaternary ammonium salts into lysosomes,creating a deprotonated environment.This environment allows drugs to bypass protonation issues in lysosomes,thereby reversing drug resistance and improving therapeutic efficacy.As a proof of concept,a quaternary ammonium salt-based pH indicator was developed,berberrubine(BRB),enhancing the action of the anticancer drug hydroxycamptothecin(HCPT)in resistant cells.BRB-induced alkalinization increased lysosomal pH and deactivated lysosomal activity,enabling HCPT to bypass protonation constraints.This enhancement markedly improved the anticancer efficacy of HCPT in resistant cells,providing an innovative approach to address drug resistance and advancing therapeutic technologies. 展开更多
关键词 Drug resistance LYSOSOMES Berberrubine HYDROXYCAMPTOTHECIN Quaternary ammonium salts alkalinization
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P,N co-doped hollow carbon nanospheres prepared by micellar copolymerization for increased hydrogen evolution in alkaline water 被引量:1
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作者 HAN Yi-meng XIONG Hao +2 位作者 YANG Jia-ying WANG Jian-gan XU Fei 《新型炭材料(中英文)》 北大核心 2025年第1期211-221,共11页
The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alka... The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alkaline water.Precise control of the electronic structure by heteroatom doping has proven to be efficient for increasing catalytic activity.Nevertheless,both the structural characteristics and the underlying mechanism are not well understood,especially for doping with two different atoms,thus limiting the use of these catalysts.We report the production of phosphorus and nitrogen co-doped hollow carbon nanospheres(HCNs)by the copolymerization of pyrrole and aniline at a Triton X-100 micelle-interface,followed by doping with phytic acid and carbonization.The unique pore structure and defect-rich framework of the HCNs expose numerous active sites.Crucially,the combined effect of graphitic nitrogen and phosphorus-carbon bonds modulate the local electronic structure of adjacent C atoms and facilitates electron transfer.As a res-ult,the HCN carbonized at 1100°C exhibited superior HER activity and an outstanding stability(70 h at a current density of 10 mA cm^(−2))in alkaline water,because of the large number of graphitic nitrogen and phosphorus-carbon bonds. 展开更多
关键词 Alkaline hydrogen evolution ELECTROCATALYSTS Hollow carbon nanospheres Dual atoms doping Combined effect
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Stabilization of clay soil using alkali-activated sewage sludge 被引量:1
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作者 Shahram Pourakbar Atiyeh Maneshmoaveni +3 位作者 Danial Moazami Laura Moretti Amirhossein Yousefi Nuno Cristelo 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期3213-3224,共12页
This study investigates the innovative reuse of sewage sludge with eco-friendly alkaline solutes to improve clayey soil without conventional cementitious binders.The unconfined compressive strength(UCS)was the main cr... This study investigates the innovative reuse of sewage sludge with eco-friendly alkaline solutes to improve clayey soil without conventional cementitious binders.The unconfined compressive strength(UCS)was the main criterion to assess the quality and effectiveness of the proposed solutions,as this test was performed to measure the strength of the stabilized clay by varying binders’dosages and curing times.Moreover,the direct shear test(DST)was used to investigate the Mohr-Coulomb parameters of the treated soil.Microstructure observations of the natural and treated soil were conducted using scanning electron microscope(SEM),energy-dispersive spectroscopy(EDS),and FTIR.Furthermore,toxicity characteristic leaching procedure(TCLP)tests were performed on the treated soil to investigate the leachability of metals.According to the results,using 2.5%of sewage sludge activated by NaOH and Na_(2)SiO_(3)increases the UCS values from 176 kPa to 1.46 MPa after 7 d and 56 d of curing,respectively.The results of the DST indicate that sewage sludge as a precursor increases cohesion and enhances frictional resistance,thereby improving the Mohr-Coulomb parameters of the stabilized soil.The SEM micrographs show that alkali-activated sewage sludge increases the integrity and reduces the cavity volumes in the stabilized soil.Moreover,TCLP tests revealed that the solubility of metals in the treated soil alkaliactivated by sewage sludge significantly decreased.This study suggests that using sewage sludge can replace cement and lime in ground improvement,improve the circular economy,and reduce the carbon footprint of construction projects. 展开更多
关键词 Soil stabilization Toxicity leaching Alkaline activation Sewage sludge Ground improvement
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Recent advancements in noble-metal electrocatalysts for alkaline hydrogen evolution reaction 被引量:1
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作者 Guoliang Gao Guangzhen Zhao +4 位作者 Guang Zhu Bowen Sun Zixu Sun Shunli Li Ya-Qian Lan 《Chinese Chemical Letters》 2025年第1期176-200,共25页
Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy infrastructure.Noble metal-based electrocatalysts,owing to thei... Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy infrastructure.Noble metal-based electrocatalysts,owing to their exceptional hydrogen binding energy,exhibit remarkable catalytic activity and long-term stability in the hydrogen evolution reaction(HER).However,the restricted accessibility and exorbitant cost of noble-metal materials pose obstacles to their extensive adoption in industrial contexts.This review investigates strategies aimed at reducing the dependence on noble-metal electrocatalysts and developing a cost-effective alkaline HER catalyst,while considering the principles of sustainable development.The initial discussion covers the fundamental principle of HER,followed by an overview of prevalent techniques for synthesizing catalysts based on noble metals,along with a thorough examination of recent advancements.The subsequent discussion focuses on the strategies employed to improve noble metalbased catalysts,including enhancing the intrinsic activity at active sites and increasing the quantity of active sites.Ultimately,this investigation concludes by examining the present state and future direction of research in the field of electrocatalysis for the HER. 展开更多
关键词 Hydrogen evolution reaction Alkaline water electrolysis ELECTROCATALYSTS Noble metal-based Synthesis method Modification strategy
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NiMo-based alloy and its sulfides for energy-saving hydrogen production via sulfion oxidation assisted alkaline seawater splitting 被引量:1
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作者 Miaosen Yang Junyang Ding +3 位作者 Zhiwei Wang Jingwen Zhang Zimo Peng Xijun Liu 《Chinese Chemical Letters》 2025年第9期595-601,共7页
Establishing an energy-saving and affordable hydrogen production route from infinite seawater presents a promising strategy for achieving carbon neutrality and low-carbon development.Compared with the kinetically slug... Establishing an energy-saving and affordable hydrogen production route from infinite seawater presents a promising strategy for achieving carbon neutrality and low-carbon development.Compared with the kinetically sluggish oxygen evolution reaction(OER),the thermodynamically advantageous sulfion oxidation reaction(SOR)enables the S^(2-)pollutants recovery while reducing the energy input of water electrolysis.Here,a nanoporous NiMo alloy ligament(np-NiMo)with AlNi_(3)/Al_(5)Mo heterostructure was prepared for hydrogen evolution reaction(HER,-0.134V versus reversible hydrogen electrode(vs.RHE)at 50mA/cm^(2)),which needs an Al_(89)Ni_(10)Mo_(1)as a precursor and dealloying operation.Further,the np-NiMo alloy was thermal-treated with S powder to generate Mo-doped NiS_(2)(np-NiMo-S)for OER(1.544V vs.RHE at 50mA/cm^(2))and SOR(0.364 V vs.RHE at 50mA/cm^(2)),while still maintaining the nanostructuring advantages.Moreover,for a two-electrode electrolyzer system with np-NiMo cathode(1M KOH+seawater)coupling np-NiMo-S anode(1mol/L KOH+seawater+1 mol/L Na_(2)S),a remarkably ultra-low cell potential of 0.532 V is acquired at 50mA/cm^(2),which is about 1.015 V below that of normal alkaline seawater splitting.The theory calculations confirmed that the AlNi_(3)/Al_(5)Mo heterostructure within np-NiMo promotes H_(2)O dissociation for excellent HER,while the Mo-dopant of np-NiMo-S lowers energy barriers for the rate-determining step from^(*)S_(4)to^(*)S_(8).This work develops two kinds of NiMo alloy with tremendous prominence for achieving energy-efficient hydrogen production from alkaline seawater and sulfur recycling from sulfion-rich sewage. 展开更多
关键词 NiMo alloy Alkaline seawater electrolysis Hydrogen production Sulfion oxidation reaction Theoretical calculation
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Trends of alkaline phosphatase to prealbumin ratio in patients with hepatitis B linked to hepatocellular carcinoma development
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作者 Wen-Chong Zhen Jing Sun +8 位作者 Xue-Ting Bai Qian Zhang Zi-Han Li Yi-Xin Zhang Rong-Xuan Xu Wei Wu Zhi-Han Yao Chun-Wen Pu Xiao-Feng Li 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期42-51,共10页
BACKGROUND Chronic hepatitis B often progresses silently toward hepatocellular carcinoma(HCC),a leading cause of mortality worldwide.Early detection of HCC is crucial,yet challenging.AIM To investigate the role of dyn... BACKGROUND Chronic hepatitis B often progresses silently toward hepatocellular carcinoma(HCC),a leading cause of mortality worldwide.Early detection of HCC is crucial,yet challenging.AIM To investigate the role of dynamic changes in alkaline phosphatase to prealbumin ratio(APR)in hepatitis B progression to HCC.METHODS Data from 4843 patients with hepatitis B(January 2015 to January 2024)were analyzed.HCC incidence rates in males and females were compared using the log-rank test.Data were evaluated using Kaplan–Meier analysis.The Linear Mixed-Effects Model was applied to track the fluctuation of APR levels over time.Furthermore,Joint Modeling of Longitudinal and Survival data was employed to investigate the temporal relationship between APR and HCC risk.RESULTS The incidence of HCC was higher in males.To ensure the model’s normality assumption,this study applied a logarithmic transformation to APR,yielding ratio.Ratio levels were higher in females(t=5.26,P<0.01).A 1-unit increase in ratio correlated with a 2.005-fold higher risk of HCC in males(95%CI:1.653-2.431)and a 2.273-fold higher risk in females(95%CI:1.620-3.190).CONCLUSION Males are more prone to HCC,while females have higher APR levels.Despite no baseline APR link,rising APR indicates a higher HCC risk. 展开更多
关键词 Alkaline phosphatase to prealbumin ratio Chronic hepatitis B patients Hepatocellular carcinoma Retrospective cohort study Linear Mixed-Effect Mode Joint Modelling of Longitudinal and Survival data
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Erosion-Corrosion of Ti(C,N)-Mo_(2)C-Ni Cermet and WC-Co Cemented Carbide in Alkaline Conditions
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作者 Deng Chengjun Lin Fukai +4 位作者 Yang Tianen Hong Huaping Liang Lei Peng Huabei Xiong Ji 《稀有金属材料与工程》 北大核心 2025年第4期886-897,共12页
Ti(C,N)-Mo_(2)C-Ni cermet as alternative materials was explored for use in alkaline conditions,replacing the WC-Co cemented carbides,since Co is classified as a potentially carcinogenic substance and there is potentia... Ti(C,N)-Mo_(2)C-Ni cermet as alternative materials was explored for use in alkaline conditions,replacing the WC-Co cemented carbides,since Co is classified as a potentially carcinogenic substance and there is potential hazard of“hard metal disease”under the exposure to cobalt dust.The changes in microstructure,corrosion rate and volumetric loss rate of the two materials were compared under electrochemical corrosion and erosion-corrosion in alkaline environment.The results demonstrates that Ti(C,N)-Mo_(2)C-Ni cermet undergoes passivation when exposed to electrochemical corrosion of NaOH solution,resulting in a significant increase in oxygen content on the corroded surface.The corrosion rate of cermet is approximately one order of magnitude lower than that of the cemented carbide.Under the erosion-corrosion of an alkaline sand-water mixture,both the cermet and cemented carbide experience a gradual increase in volumetric loss rate with prolonging the erosion time.During erosion,the rim phase in cermet is fragile,so cracks easily penetrate it while the core phase remains intact.The medium-grained cemented carbide commonly demonstrates transgranular fracture mode,while in the fine-grained cemented carbide,cracks tend to propagate along phase boundaries.The erosive wear and damage caused by sand particles play a predominant role in the erosion-corrosion process of alkaline sand-water mixtures.This process represents an accelerated destructive phenomenon influenced and intensified by the combined effects of corrosion and erosion.It is confirmed that using cermet as an alternative anti-wear material to cemented carbides is feasible under alkaline conditions,and even better. 展开更多
关键词 CERMET cemented carbide EROSION-CORROSION electrochemical corrosion alkaline conditions
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cAMP:A second messenger involved in the mechanism of midgut alkalinization in Lutzomyia longipalpis
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作者 Denise Barguil Nepomuceno Grasielle Caldas D’Ávila Pessoa +4 位作者 Leonardo Barbosa Koerich Marcos Horácio Pereira Mauricio Roberto Viana Sant'Anna Ricardo Nascimento Araújo Nelder Figueiredo Gontijo 《Insect Science》 SCIE CAS CSCD 2022年第4期1059-1070,共12页
The sand fly Lutzomyia longipalpis is the main vector of Leishmania infantum in the Americas.Female sand flies ingest sugar-rich solutions and blood,which are digested in the midgut.Digestion of nutrients is an essent... The sand fly Lutzomyia longipalpis is the main vector of Leishmania infantum in the Americas.Female sand flies ingest sugar-rich solutions and blood,which are digested in the midgut.Digestion of nutrients is an essential function performed by digestive enzymes,which require appropriate physiological conditions.One of the main aspects that influence enzymatic activity is the gut pH,which must be tightly controlled.Considering second messengers are frequently involved in the coordination of tightly regulated physiological events,we investigated if the second messenger cAMP would participate in the process of alkalinization in the abdominal midgut of female L.longipalpis.In midguts containing the indicator dye bromothymol-blue,cAMP stimulated the alkalinization of the midgut lumen.Through another technique based on the use of fluorescein as a pH indicator,we propose that cAMP is involved in the alkalinization of the midgut by activating HCO3-transport from the enterocyte's cytoplasm to the lumen.The results strongly suggested that the carrier responsible for this process would be a HCO3−/Cl−antiporter located in the enterocytes’apical membrane.Hematophagy promotes the release of alkalinizing hormones in the hemolymph;however,when the enzyme adenylyl cyclase,responsible for cAMP production,was inhibited,we observed that the hemolymph from blood-fed L.longipalpis’females did not stimulate midgut alkalinization.This result indicated that hormone-stimulated alkalinization is mediated by cAMP.In the present study,we provide evidences that cAMP has a key role in the control of intestinal pH. 展开更多
关键词 abdominal midgut alkalinization CAMP HCO_(3)^(-)/Cl^(-)antiport HORMONE Lulcomyia longipalpis
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An Ultra‑Stable, High‑Energy and Wide‑Temperature‑Range Aqueous Alkaline Sodium‑Ion Battery with the Microporous C_(4)N/ rGO Anode
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作者 Mengxiao Li Rui Li +8 位作者 Huige Ma Mingsheng Yang Yujie Dai HaiPing Yu Yuxin Hao Zhihui Wang Bei Wang Mingjun Hu Jun Yang 《Nano-Micro Letters》 2025年第7期160-176,共17页
Common anode materials in aqueous alkaline electrolytes,such as cadmium,metal hydrides and zinc,usually suffer from remarkable biotoxicity,high cost,and serious side reactions.To overcome these problems,we develop a c... Common anode materials in aqueous alkaline electrolytes,such as cadmium,metal hydrides and zinc,usually suffer from remarkable biotoxicity,high cost,and serious side reactions.To overcome these problems,we develop a conjugated porous polymer(CPP)in-situ grown on reduced graphene oxide(rGO)and Ketjen black(KB),noted as C_(4)N/rGO and C_(4)N/KB respectively,as the alternative anodes.The results show that C_(4)N/rGO electrode delivers a low redox potential(−0.905 V vs.Ag/AgCl),high specific capacity(268.8 mAh g^(-1) at 0.2 A g^(-1)),ultra-stable and fast sodium ion storage behavior(216 mAh g^(-1) at 20 A g^(-1))in 2 M NaOH electrolyte.The assembled C_(4)N/rGO//Ni(OH)_(2) full battery can cycle stably more than 38,000 cycles.Furthermore,by adding a small amount of antifreeze additive dimethyl sulfoxide(DMSO)to adjust the hydrogen bonding network,the low-temperature performance of the electrolyte(0.1 DMSO/2 M NaOH)is significantly improved while hydrogen evolution is inhibited.Consequently,the C_(4)N/rGO//Ni(OH)_(2) full cell exhibits an energy density of 147.3 Wh Kg^(-1) and ultra-high cycling stability over a wide temperature range from−70 to 45℃.This work provides an ultra-stable high-capacity CPPbased anode and antifreeze electrolyte for aqueous alkaline batteries and will facilitate their practical applications under extreme conditions. 展开更多
关键词 Aqueous alkaline batteries Organic anode Ultra-high cycling stability Alkaline antifreeze electrolyte Wide temperature range
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Hypophosphatasia:A case report
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作者 Angad Singh Gill Pallavi Sharma +1 位作者 Mahmoud Nassar Erlin Marte 《World Journal of Clinical Cases》 2025年第21期71-77,共7页
BACKGROUND Hypophosphatasia(HPP)is a rare metabolic disorder caused by low tissue-nonspecific alkaline phosphatase(ALP)activity,presenting symptoms from bone demineralization to tooth loss.It affects multiple systems ... BACKGROUND Hypophosphatasia(HPP)is a rare metabolic disorder caused by low tissue-nonspecific alkaline phosphatase(ALP)activity,presenting symptoms from bone demineralization to tooth loss.It affects multiple systems and is diagnosed based on clinical symptoms,radiological findings,and lab tests.This case report empha-sizes considering HPP in patients with unexplained bone pain and low ALP levels,especially with underlying osteopenia or osteoporosis.It highlights the importance of genetic testing and counseling for early diagnosis and treatment,aiming to raise clinician awareness.CASE SUMMARY We present a case of a 65-year-old female patient who was referred to our endoc-rinology clinic for complaints of generalized bone pain and hypothyroidism.Initial evaluation revealed osteopenia,managed with calcium and vitamin D supplementation.Persistently low ALP levels and elevated vitamin B6 levels led to the diagnosis of HPP,confirmed by genetic testing identifying a pathogenic ALPL gene variant[c.119C>T(p.Ala40Val)].Despite conservative treatment,her bone density declined,although remaining in the osteopenic range.The Fracture Risk Assessment score indicated a low risk of major osteoporotic and hip fractures,not warranting immediate treatment.Plans are underway to initiate enzyme replacement therapy with asfotase alfa.CONCLUSION Recognizing HPP is crucial,as early diagnosis and treatment can significantly improve patient outcomes and prevent complications. 展开更多
关键词 HYPOPHOSPHATASIA Tissue-nonspecific alkaline phosphatase OSTEOPENIA Enzyme replacement therapy Asfotase alfa Low alkaline phosphatase levels Vitamin B6 metabolism Skeletal hypomineralization Rare metabolic disorders Adultonset hypophosphatasia Case report
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Uncover the Diagenetic Water Condition and Dolomite Formation in the Songliao Basin 91 Ma
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作者 Yuke Liu Huajian Wang +3 位作者 Jinyou Zhang Yuntao Ye Xiaomei Wang Shuichang Zhang 《Journal of Earth Science》 2025年第3期1109-1128,共20页
Lacustrine dolomite is paid increasing attention to uncover the diagenetic water condition of paleo-lake and“dolomite problem”.Here,a dolomite nodule from the Qingshankou Formation in the Songliao Basin was analyzed... Lacustrine dolomite is paid increasing attention to uncover the diagenetic water condition of paleo-lake and“dolomite problem”.Here,a dolomite nodule from the Qingshankou Formation in the Songliao Basin was analyzed to explore the salinity,alkalinity,and redox conditions of the diagenetic water.Multiple proxies,including bulk boron(B)content,B isotope composition(δ^(11)B_(bul)),boron to gallium weight ratio(B/Ga)and carbonate oxygen isotope composition(δ^(18)O_(carb)),were used to determine the diagenetic water to be brackish-fresh.Through numerical simulation,we calculated the B contents,δ^(11)B values and B/Ga in detritus(e.g.,clay,quartz and feldspar)and dolomite as two endmembers,confirming the intense interference of clay minerals onδ^(11)B_(bul).By using the fittedδ^(11)B of dolomite endmember(20.6‰),we calculated the p H value of the diagenetic water to be 8.2.The negativeδ^(11)B value of detritus endmember(-12.9‰)might be related to the terrestrial weathering.The indicative nature of strontium to barium weight ratio(Sr/Ba)was discussed to deny its applicability as a proxy of salinity in carbonate system.High Sr/Ba ratio in this dolomite nodule indicates a sulfate-poor water condition,consistent with the iron-manganese(Fe-Mn)reduction environments reflected by the Mn/Fe molar ratio.The positive carbonate carbon isotopes(δ^(13)C_(carb),4.5‰-9.4‰)indicate that methanogenesis dominated the formation of dolomite,coinciding with the weak sulfate reduction reaction in sulfate-poor water.The growth of dolomite nodule might be related to the microbial activities of methanogen and iron reducing bacteria,which had not only maintained the salinity,p H,and redox status of the diagenetic water,but also led to a ferricmethane transition zone(FMTZ).This research depicts a scenario about the diagenetic water environment of lacustrine dolomite formed in brackish-fresh water,which is different from that occurred in sulfate-rich condition. 展开更多
关键词 DOLOMITE boron Qingshankou Formation LACUSTRINE ALKALINITY salinity redox
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Assessment of Groundwater Quality and Suitability for Irrigation Purpose in Northern Babil Governorate
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作者 Mohammed Malik Hamid Raad Farhan Shahad Mohammad Tarkhan Abo Almekh 《Journal of Environmental & Earth Sciences》 2025年第4期368-377,共10页
Groundwater is considered a vital source for agriculture,especially in areas that suffer from a shortage of surface water resources.Accordingly,this study was conducted to evaluate the concentrations of some polluting... Groundwater is considered a vital source for agriculture,especially in areas that suffer from a shortage of surface water resources.Accordingly,this study was conducted to evaluate the concentrations of some polluting elements and some chemical properties of well water north of Babylon city to show its suitability for irrigation purposes.The(pH,EC,calcium,magnesium,sodium,potassium,chloride,carbonates,bicarbonates,sulfates,nitrates,and boron)and some heavy elements(cadmium,lead,copper,and nickel)were estimated over four time periods(July 2023,October 2023,January 2024,April 2024)and for the regions(Latifiya,Al-Musayyab,Haswa,and Alexandria).The results showed that the electrical conductivity of well water falls within the category that causes a severe salinity problem,according to Ayera and Westcot,and the pH of the water was within the normal range,tending toward light alkalinity.The sodium values fell within the category that causes a severe problem,and that the chloride concentrations were high and within the category of water that causes a severe problem according to the classification of Marsh.The concentration of boron was low to moderate for sensitive crops.Regarding the nitrate content,well water is classified as no problem.The concentrations of all heavy metals were within the permissible limits,except for cadmium,which exceeded the permissible limits according to the global specifications of the World Health Organization. 展开更多
关键词 Heavy Metals Water Pollution GROUNDWATER CADMIUM ALKALINITY
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Alkaline igneous rocks,a potential source of rare metals and radioactive minerals:Case study at Amreit area,south Eastern Desert,Egypt
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作者 Baaha M.Emad 《Acta Geochimica》 2025年第1期189-214,共26页
Alkaline igneous rocks represent one of the most economically important resources of radioactive minerals and rare metals.New field observations and petrographic studies are integrated with whole-rock geochemical anal... Alkaline igneous rocks represent one of the most economically important resources of radioactive minerals and rare metals.New field observations and petrographic studies are integrated with whole-rock geochemical analyses and Gamma ray spectroscopy data of alkaline rocks associated with the Amreit complex.The fieldwork was achieved by the collection of more than forty samples from alkaline granites and alkaline syenites.The youngest rocks cropping out in the study area are the cogenetic alkaline rocks,ranging from alkaline granite to alkaline syenite.These alkaline rocks are composed essentially of K-feldspar,alkali amphiboles(arfvedsonite),and sodic pyroxene,with accessories such as zircon,apatite,and ilmenite.Mineral characterization of the highly radioactive zones in both alkaline granite and alkaline syenite displays enrichment in monazite,thorite,zircon,ferro-columbite,xenotime,and allanite minerals.Geochemical analyses indicate that the Amreit rocks are alkaline with peralkaline affinity and have high concentrations of total alkalis(K_(2)O+Na_(2)O),large ion lithophile elements(LILEs;Ba and Rb),high field strength elements(HFSEs;Y,Zr and Nb),rare earth elements(REEs)and significantly depleted in K,Sr,P,Ti,and Eu,typically of post-collision A-type granites.Typically,the Amreit alkaline igneous rocks are classified as within plate granites and display A2 subtype characteristics.The fractionation of K-feldspars played a distinctive role during the magmatic evolution of these alkaline rocks.The geochemical characteristics indicate that the studied alkaline igneous rocks which were originated by fractional crystallization of alkaline magmas were responsible for the enrichment of the REE and rare metals in the residual melt.The high radioactivity is essentially related to accessory minerals,such as zircon,allanite,and monazite.The alkaline granite is the most U-and Thrich rock,where radioactivity level reaches up to 14.7 ppm(181.55 Bq/kg)e U,40.6 ppm(164.84 Bq/kg)e Th,whereas in alkaline syenite radioactivity level is 8.5 ppm(104.96 Bq/kg)e U,30.2 ppm(122.61 Bq/kg)e Th.These observations suppose that these alkaline rocks may be important targets for REEs and radioactive mineral exploration. 展开更多
关键词 Amreit area Alkaline rocks RADIOACTIVITY Geochemistry Post-collision A-type granite EGYPT
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In situ Construction of Free-Standing High-Performance Ni-Based Dual Intermetallic Composites for Alkaline Hydrogen Evolution
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作者 Xu Wang Qian Li +5 位作者 Shuzhao Feng Yan Liu Caixia Xu Qiuxia Zhou Hong Liu Qingyu Yan 《Transactions of Tianjin University》 2025年第2期131-144,共14页
Alkaline electrolytic hydrogen production has emerged as one of the most practical methods for industrial-scale hydrogen production.However,the initial hydrolysis dissociation in alkaline media impedes the hydrogen ev... Alkaline electrolytic hydrogen production has emerged as one of the most practical methods for industrial-scale hydrogen production.However,the initial hydrolysis dissociation in alkaline media impedes the hydrogen evolution reaction(HER)kinetics of commercial catalysts.To overcome this limitation,this study focuses on the development of a highly efficient electrocatalyst for alkaline HER.Ni-based intermetallic compounds exhibit remarkable catalytic activity for HER,with the NiMo alloy being among the most active catalysts in alkaline environments.Here,we designed and fabricated self-supported multiscale porous NiZn/NiMo intermetallic compounds on a metal foam substrate using a versatile dealloying method.The resulting electrode exhibits excellent HER activity,achieving an overpotential of just 204 mV at 1000 mA/cm^(2),and dem-onstrates robust long-term catalytic stability,maintaining performance at 100 mA/cm^(2) for 400 h in an alkaline electrolyte.Thesefindings underscore the potential of nanosized intermetallic compounds fabricated via a dealloying approach to deliver exceptional catalytic performance for alkaline water electrolysis. 展开更多
关键词 Alkaline hydrogen evolution INTERMETALLIC NIMO DEALLOYING Multiscale porous structure
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Continuous-flow synthesis of pentaerythritol:Alkalinity release of sodium solvation cage to control aldol and Cannizzaro reactions
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作者 Zhengguang Wang Xin Qu +6 位作者 Xingke Yuan Zhanpeng Gao Niu Hu Jiansheng Wei Wenpeng Li Zhirong Yang Jingtao Wang 《Chinese Journal of Chemical Engineering》 2025年第3期23-29,共7页
Continuous-flow upgrading of pentaerythritol synthesis technology via base-catalyzed aldol and Cannizzaro reactions of formaldehyde and acetaldehyde faces the challenge of effectively controlling the critical side rea... Continuous-flow upgrading of pentaerythritol synthesis technology via base-catalyzed aldol and Cannizzaro reactions of formaldehyde and acetaldehyde faces the challenge of effectively controlling the critical side reaction of hydroxymethyl acetaldehyde(HA)to the acrolein intermediate.Here,we first identified the forms of industrial formaldehyde as methane diol that easily converts to the alkaline formaldehyde under alkaline(NaOH)environment.The carbonyl group of alkaline formaldehyde induces deprotonation of acetaldehyde instead of the recognized base-hydroxyl group-induced deprotonation,and it needs to overcome only 18.31 kcal·mol^(-1)(1 kcal=4.186 kJ)energy barrier to form key intermediates of HA.The sodium solvation cage formed by NaOH hexa-coordinated formaldehyde effectively inhibits the alkalinity,thus contributing to a high energy barrier(46.21 kcal·mol^(-1))to unwanted acrolein formation.In addition,the solvation cage gradually opens to increase the alkalinity with the consumption of formaldehyde,thus facilitating the subsequent Cannizzaro reaction(to overcome 11.77 kcal·mol^(-1)).In comparison,strong alkalinity promotes the formation of acrolein(36.65 kcal·mol^(-1))to initiate the acetal side reaction,while weak alkalinity reduces the possibility of the Cannizzaro reaction(to overcome 20.44 kcal·mol^(-1)).This theoretically reveals the importance of the segmented feeding of weak and strong bases to successively control the aldol reaction and Cannizzaro reaction,and the combination of Na_(2)CO_(3) or HCOONa with NaOH improves the pentaerythritol yield by 7%to 13%compared to that of NaOH alone(70%yield)within 1 min at a throughput of 155.7 ml·min^(-1). 展开更多
关键词 Alkaline formaldehyde Sodium solvation cage Aldol reaction Cannizzaro reaction CONTINUOUS-FLOW PENTAERYTHRITOL
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Machine Learning Prediction and Feature Impact Analysis of Durability Performance of Solid Waste-Alkali Activated Cementitious Materials
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作者 WEI Wei DING Yongjie +2 位作者 ZHOU Yongxiang WANG Jiaojiao WANG Yanghui 《Journal of Wuhan University of Technology(Materials Science)》 2025年第5期1330-1348,共19页
This study applied machine learning methods to predict the durability performance(specifically shrinkage and freeze-thaw resistance)of solid waste-activated cementitious materials.It also offered insights for optimizi... This study applied machine learning methods to predict the durability performance(specifically shrinkage and freeze-thaw resistance)of solid waste-activated cementitious materials.It also offered insights for optimizing material formulations through feature impact analysis.The study collected a total of 130 sets of shrinkage data and 106 sets of freeze-thaw data,establishing various models,including BP,GA-BP,SVM,RF,RBF,and LSTM.The results revealed that the SVM model performed the best on the test dataset.It achieved an R^(2) of 0.9358 for shrinkage prediction,with MAE and RMSE values of 0.4644 and 0.6254,respectively.Regarding freeze-thaw quality loss prediction,the R^(2) was 0.9178,with MAE and RMSE values of 0.3139 and 0.5328,respectively.The study analyzed the impact of different features on the outcomes using the SHAP method,highlighting that the alkaline activator dosage,Al_(2)O_(3),SiO_(2),and water glass modulus were critical factors influencing shrinkage,while CaO,water-cement ratio,water,and Al_(2)O_(3) were crucial for freeze-thaw resistance.By investigating feature interactions through single-factor and two-factor analysis,the study proposed recommendations for optimizing material formulations.This research validated the efficacy of machine learning in predicting the durability of solid waste cementitious materials and offered insights for material optimization through feature impact analysis,thereby laying the groundwork for the development of related materials. 展开更多
关键词 machine learning alkaline activation solid waste cementitious materials SHAP DURABILITY
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Toward the rational engineering of Mo-based materials for alkaline oxygen evolution reaction
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作者 Qingcui Liu Wenhua Cheng +4 位作者 Yudai Huang Huan Zhou Juan Ding Weiwei Meng Zhouliang Tan 《Journal of Energy Chemistry》 2025年第7期751-767,共17页
A thorough understanding of the oxygen evolution reaction(OER)in Mo-based materials is crucial for the advancement of water-splitting technologies.However,the identification of the active phase in Mo-based systems rem... A thorough understanding of the oxygen evolution reaction(OER)in Mo-based materials is crucial for the advancement of water-splitting technologies.However,the identification of the active phase in Mo-based systems remains a subject of debate,largely due to the dissolution of molybdenum oxides in alkaline electrolytes.In this review,we provide a comprehensive overview of recent advances in the application of Mo-based materials for OER in alkaline media,with an emphasis on their diverse roles in catalysis.Various design strategies employed to optimize Mo-based materials are discussed,focusing on how these approaches influence their physicochemical properties and the specific effects of different design perspectives on their OER performance.Additionally,the structure-performance relationship underlying these materials is explored,offering insights into how structural modifications impact catalytic efficiency.Lastly,key challenges for Mo-based materials in OER applications are provided,and future research directions for further improving the efficacy of sustainable water-splitting technologies in alkaline environments are proposed. 展开更多
关键词 Mo-based materials Structure-performance relationship Oxygen evolution reaction Alkaline media ELECTROCATALYSIS
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Vacuum ammonia stripping from liquid digestate:Effects of pH,alkalinity,temperature,negative pressure and process optimization
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作者 Qiuhong Chen Donghai Yang +3 位作者 Xiang Chen Xiankai Wang Bin Dong Xiaohu Dai 《Journal of Environmental Sciences》 2025年第3期638-650,共13页
High ammonia-nitrogen digestate has become a key bottleneck limiting the anaerobic digestion of organic solid waste.Vacuum ammonia stripping can simultaneously remove and recover ammonia nitrogen,which has attracted a... High ammonia-nitrogen digestate has become a key bottleneck limiting the anaerobic digestion of organic solid waste.Vacuum ammonia stripping can simultaneously remove and recover ammonia nitrogen,which has attracted a lot of attention in recent years.To investigate the parameter effects on the efficiency and mass transfer,five combination conditions(53℃ 15 kPa,60°C 20 kPa,65°C 25 kPa,72°C 35 kPa,and 81°C 50 kPa)were conducted for ammonia stripping of sludge digestate.The results showed that 80%of ammonia nitrogen was stripped in 45 min for all experimental groups,but the ammonia transfer coefficient varied under different conditions,which increased with the rising of boiling point temperature,and reached the maximum value(39.0 mm/hr)at 81°C 50 kPa.The ammonia nitrogen removal efficiency was more than 80%for 30 min vacuum stripping after adjusting the initial pH to above 9.5,and adjustment of the initial alkalinity also affects the pH value of liquid digestate.It was found that pH and alkalinity are the key factors influencing the ammonia nitrogen dissociation and removal efficiency,while temperature and vacuum mainly affect the ammonia nitrogen mass transfer and removal velocity.In terms of the mechanism of vacuum ammonia stripping,it underwent alkalinity destruction,pH enhancement,ammonia nitrogen dissociation,and free ammonia removal.In this study,two-stage experiments of alkalinity destruction and ammonia removal were also carried out,which showed that the two-stage configuration was beneficial for ammonia removal.It provides a theoretical basis and practical technology for the vacuum ammonia stripping from liquid digestate of organic solid waste. 展开更多
关键词 Liquid digestate Vacuum ammonia stripping ALKALINITY Mass transfer Process optimization
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Microscopic oil occurrence in the Permian alkaline lacustrine shales:Fengcheng formation,Mahu Sag,Junggar basin
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作者 Jia-Hao Lv Tao Hu +7 位作者 Wang Zhang Fu-Jie Jiang Jing Xue Chen-Xi Zhang Zhen-Guo Qi Ren-Da Huang Mei-Ling Hu Shu Jiang 《Petroleum Science》 2025年第4期1407-1427,共21页
Alkaline lacustrine shale is highly heterogeneous,and the complex relationship between the organicinorganic porosity network and hydrocarbon occurrence restricts the effectiveness of shale oil exploration and developm... Alkaline lacustrine shale is highly heterogeneous,and the complex relationship between the organicinorganic porosity network and hydrocarbon occurrence restricts the effectiveness of shale oil exploration and development.Herein,we investigated the Fengcheng Formation(P_(1)f)in Mahu Sag.This study integrated geochemistry,Soxhlet extraction,scanning electron microscopy,gas adsorption,and nuclear magnetic resonance T_(1)-T_(2)spectroscopy to elucidate the microscopic oil occurrence mechanisms in shales.Results indicate the presence of felsic shale,dolomitic shale,lime shale,and mixed shale within the P_(1)f.Matrix pores and microfractures associated with inorganic minerals are the predominant pore types in P_(1)f.Adsorbed oil primarily resides on the surfaces of organic matter and clay minerals,while free oil predominantly occupies inorganic pores and microfractures with larger pore sizes.Variations exist in the quantity and distribution of shale oil accumulation across different scales,where free oil and adsorbed oil are governed by dominant pores with diameters exceeding 10 nm and ineffective pores with diameters below 10 nm,respectively.Shale oil occurrence characteristics are influenced by organic matter,pore structure,and mineral composition.Felsic shale exhibits a high abundance of dominant pores,possesses the highest oil content,predominantly harbors free oil within these dominant pores,and demonstrates good mobility.Fluid occurrence in dolomitic shale and lime shale is intricate,with low oil content and a free oil to adsorbed oil ratio of 1:1.Mixed shale exhibits elevated clay mineral content and a scarcity of dominant pores.Moreover,ineffective pores contain increased bound water,resulting in medium oil content and limited mobility predominantly due to adsorption.Presently,shale oil mainly occurs in the dominant pores with a diameter larger than 10 nm in a free state.During the exploration and development of alkaline lacustrine shale oil resources,emphasis should be placed on identifying sweet spots within the felsic shale characterized by dominant pores. 展开更多
关键词 Alkaline lacustrine shale Mahu sag Fengchengformation Shale oil Occurrence mechanism
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