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Fe(Ⅱ)对CANON工艺处理城镇污水脱氮性能的影响
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作者 张倩倩 廖祖刚 +3 位作者 冯泽通 刘金泽 符文婧 赵剑强 《安全与环境工程》 CAS CSCD 北大核心 2024年第2期291-300,共10页
全程自养脱氮(CANON)工艺,作为新型脱氮工艺应用于城镇污水深度脱氮过程中,有望降低污水处理的运行费用。考察了亚铁离子[Fe(Ⅱ)]对CANON工艺启动及稳定运行时脱氮性能的影响。结果表明:15~23℃条件下投加6.3 mg/L Fe(Ⅱ)时,可有效启动... 全程自养脱氮(CANON)工艺,作为新型脱氮工艺应用于城镇污水深度脱氮过程中,有望降低污水处理的运行费用。考察了亚铁离子[Fe(Ⅱ)]对CANON工艺启动及稳定运行时脱氮性能的影响。结果表明:15~23℃条件下投加6.3 mg/L Fe(Ⅱ)时,可有效启动并稳定运行CANON工艺处理城镇污水,该工艺氮去除负荷(NRR)、总氮去除率(TNRE)和氨氮去除率(ARE)分别为(4.8±1.1)g-N/(L^(3)·d)、(97±1)%和(44.2±9.3)%;相关性分析表明,通过调控Fe(Ⅱ)投加量可有效抑制亚硝酸盐氧化菌(NOB)的活性;本次优化的Fe(Ⅱ)投加量为6.3 mg/L,其对CANON工艺脱氮性能的影响机制与CANON工艺中功能微生物活性的提高、Fe(Ⅱ)与进水氨氮及其他氮化合物的循环反应、铁型反硝化过程以及铁型厌氧氨氧化过程的耦合有关。 展开更多
关键词 canon工艺 城镇污水 Fe(Ⅱ) 脱氮效能
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Enhanced nitrite electroreduction to ammonia via interfacial dual-site adsorption
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作者 Xiaokang Chen Shengliang Zhai +4 位作者 Yi Tan Le Su Dong Zhai Wei-Qiao Deng Hao Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期328-335,共8页
The nitrite(NO_(2)^(−))to ammonia(NH3)electroreduction reaction(NO_(2)^(−)RR)would be impeded by sluggish proton-coupled electron transfer kinetics and competitive hydrogen evolution reaction(HER).A key to improving t... The nitrite(NO_(2)^(−))to ammonia(NH3)electroreduction reaction(NO_(2)^(−)RR)would be impeded by sluggish proton-coupled electron transfer kinetics and competitive hydrogen evolution reaction(HER).A key to improving the NH_(3) selectivity is to facilitate adsorption and activation of NO_(2)^(−),which is generally undesirable in unitary species.In this work,an efficient NO_(2)^(−)RR catalyst is constructed by cooperating Pd with In2O3,in which NO_(2)^(−)could adsorb on interfacial dual-site through“Pd–N–O–In”linkage,leading to strengthened NO_(2)^(−)adsorption and easier N=O bond cleavage than that on unitary Pd or In2O3.Moreover,the Pd/In_(2)O_(3)composite exhibits moderate H^(*)adsorption,which may facilitate protonation kinetics while inhibiting competitive HER.As a result,it exhibits a fairly high NH_(3)yield rate of 622.76 mmol h^(−1)g^(−1)cat with a Faradaic efficiency(FE)of 95.72%,good selectivity of 91.96%,and cycling stability towards the NO_(2)^(−)RR,surpassing unitary In_(2)O_(3)and Pd/C electrocatalysts.Besides,computed results indicate that NH_(3)production on Pd/In_(2)O_(3)follows the deoxidation to hydrogenation pathway.This work highlights the significance of H^(*)and NO_(2)^(−)adsorption modulation and N=O activation in NO_(2)^(−)RR electrochemistry by creating synergy between a mediocre catalyst with an appropriate cooperator. 展开更多
关键词 Dual-site adsorption nitrite electroreduction AMMONIA Pd Hydrogenation
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CRABP1-mediated non-canonical retinoic acid signaling in motor neurons and neural stem cells
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作者 Li-Na Wei 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1169-1170,共2页
Retinoic acid(RA),the active metabolite of vitamin A(the retinoids),elicits a wide spectrum of biological activities critical to the development and health of most of the organ systems including the nervous systems(Co... Retinoic acid(RA),the active metabolite of vitamin A(the retinoids),elicits a wide spectrum of biological activities critical to the development and health of most of the organ systems including the nervous systems(Corcoran et al.,2002).The effects of RA are mediated by two very distinct pathways;the first is manifested in the nucleus by binding to a large family of nuclear RA receptors(RARs)to regulate proper expression of RAtargeted genes. 展开更多
关键词 canonICAL SPECTRUM CRITICAL
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Assessment of Nitrates and Nitrites in Borehole Water from the Southern and the Northern Region of Côte d’Ivoire (West Africa)
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作者 Jean Stéphane Claon Kouassi Kouakou Serge +5 位作者 Sérikipré Laurent Seka M’Bassidjé Arsène N’Guettia Kossonou Roland Traoré Aïcha Djamanallico Joseph Kouadio Kouakou Luc 《Open Journal of Modern Hydrology》 CAS 2024年第2期87-105,共19页
This study aimed to evaluate the quality of water from village boreholes by measuring physicochemical parameters such as nitrates, nitrites, and total organic carbon (TOC). Forty-five (45) village pumps from the South... This study aimed to evaluate the quality of water from village boreholes by measuring physicochemical parameters such as nitrates, nitrites, and total organic carbon (TOC). Forty-five (45) village pumps from the Southern (Basse Côte) and the Northern (Korhogo) region of Cte d’Ivoire (west Africa) were sampled. Physicochemical parameters such as temperature, pH, conductivity at 25˚C, and turbidity were determined in situ, while nitrite and nitrate were analyzed according to ISO 10304-1 (2007) standard and total organic carbon (TOC) by NF EN 1484 (1997) standard. The results showed that the borehole waters of the Basse Côte and Korhogo analyzed are acidic, with an average temperature of 27.51˚C ± 0.16˚C and 29.95˚C ± 0.51˚C respectively for the Basse Côte and Korhogo regions. The borehole waters of the Basse Côtedo not contain nitrites, while those of Korhogo have average nitrite contents of 0.32 mg/l. The average nitrate rate in the waters of the Basse Côte and Korhogo are 12.08 ± 2.11 mg/l and 11.03 ± 3.18 mg/l respectively. The average TOC concentration of the waters of the Basse Côte is 1.28 ± 0.32 mg/l and that of Korhogo is 0.56 ± 0.09 mg/L. The study showed that the borehole waters of the Basse Côte and Korhogo have average temperatures between 27.4˚C and 29.95˚C with a slightly acidic pH value and acceptable salinity. The TOC concentrations obtained at the different sampling points were all below the French standard (2 mg/L) except for certains pumps of the Basse Côte. The water samples from the Basse Côte were devoid of nitrite. On the other hand, those from Korhogo revealed the presence of nitrite. Also, the borehole waters of the regions of the Basse Côte and Korhogo contain relatively high nitrate contents, presumably due to anthropometric activity. Overall, our study on the quality of drinking water showed that the waters analyzed are in compliance with international standards and safe for consumption. 展开更多
关键词 Drinking Water pH TURBIDITY TOC NITRATES nitriteS Health Effect
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Comprehensive understanding of the thriving electrocatalytic nitrate/nitrite reduction to ammonia under ambient conditions
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作者 Xinying Zhao Yuzhuo Jiang +5 位作者 Mengfan Wang Yunfei Huan Qiyang Cheng Yanzheng He Tao Qian Chenglin Yan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期459-483,共25页
Ammonia(NH_(3))is a multifunctional compound that is an important feedstock for the agricultural and pharmaceutical industries and attractive energy storage medium.At present,NH_(3)synthesis is highly dependent on the... Ammonia(NH_(3))is a multifunctional compound that is an important feedstock for the agricultural and pharmaceutical industries and attractive energy storage medium.At present,NH_(3)synthesis is highly dependent on the conventional Haber–Bosch process that operates under harsh conditions,which consumes large quantities of fossil fuels and releases a large amount of carbon dioxide.As an alternative,electrosynthesis is a prospective method for producing NH_(3)under normal temperature and pressure conditions.Although electrocatalytic nitrogen reduction to ammonia has attracted considerable attentions,the low solubility of N_(2)and high N≡N cracking energy render the achievements of high NH_(3) yield rate and Faradaic efficiency difficult.Nitrate and nitrite(NO_(x)^(-))are common N-containing pollutants.Due to their high solubilities and low dissociation energy of N=O,NO_(x)^(-)−are ideal raw materials for NH_(3) production.Therefore,electrocatalytic NO_(x)^(-)−reduction to NH_(3)(eNO_(x)RR)is a prospective strategy to simultaneously realise environmental protection and NH_(3) synthesis.This review offers a comprehensive understanding of the thriving eNO_(x)RR under ambient conditions.At first,the popular theory and mechanism of eNO_(x)RR and a summary of the measurement system and evaluation criteria are introduced.Thereafter,various strategies for developing NO_(x)−reduction catalysts are systematically presented and discussed.Finally,the challenges and possible prospects of electrocatalytic NO_(x)^(-1) reduction are outlined to facilitate energy-saving and environmentally friendly large-scale synthesis of NH_(3) in the future. 展开更多
关键词 Electrocatalytic nitrate reduction Electrocatalytic nitrite reduction Ammonia synthesis Pollutant removal ELECTROSYNTHESIS
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Cross-Project Software Defect Prediction Based on SMOTE and Deep Canonical Correlation Analysis
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作者 Xin Fan Shuqing Zhang +2 位作者 Kaisheng Wu Wei Zheng Yu Ge 《Computers, Materials & Continua》 SCIE EI 2024年第2期1687-1711,共25页
Cross-Project Defect Prediction(CPDP)is a method that utilizes historical data from other source projects to train predictive models for defect prediction in the target project.However,existing CPDP methods only consi... Cross-Project Defect Prediction(CPDP)is a method that utilizes historical data from other source projects to train predictive models for defect prediction in the target project.However,existing CPDP methods only consider linear correlations between features(indicators)of the source and target projects.These models are not capable of evaluating non-linear correlations between features when they exist,for example,when there are differences in data distributions between the source and target projects.As a result,the performance of such CPDP models is compromised.In this paper,this paper proposes a novel CPDP method based on Synthetic Minority Oversampling Technique(SMOTE)and Deep Canonical Correlation Analysis(DCCA),referred to as S-DCCA.Canonical Correlation Analysis(CCA)is employed to address the issue of non-linear correlations between features of the source and target projects.S-DCCA extends CCA by incorporating the MlpNet model for feature extraction from the dataset.The redundant features are then eliminated by maximizing the correlated feature subset using the CCA loss function.Finally,cross-project defect prediction is achieved through the application of the SMOTE data sampling technique.Area Under Curve(AUC)and F1 scores(F1)are used as evaluation metrics.This paper conducted experiments on 27 projects from four public datasets to validate the proposed method.The results demonstrate that,on average,our method outperforms all baseline approaches by at least 1.2%in AUC and 5.5%in F1 score.This indicates that the proposed method exhibits favorable performance characteristics. 展开更多
关键词 Cross-project defect prediction deep canonical correlation analysis feature similarity
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Acquired methemoglobinemia in a third trimester puerpera and her premature infant with sodium nitrite poisoning:A case report
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作者 Dong-Sheng Fei Yang Gao +6 位作者 Xue-Jiao Bao Yu-Jia Tang Yi-Lu Lin Jia-Xi Xu Jia-Ning Zhang Bo-Wen Liu Kai Kang 《World Journal of Clinical Cases》 SCIE 2024年第22期5151-5158,共8页
BACKGROUND The common cause of sodium nitrite poisoning has shifted from previous accidental intoxication by exposure or ingestion of contaminated water and food to recent alarming intentional intoxication as an emplo... BACKGROUND The common cause of sodium nitrite poisoning has shifted from previous accidental intoxication by exposure or ingestion of contaminated water and food to recent alarming intentional intoxication as an employed method of suicide/exit.The subsequent formation of methemoglobin(MetHb)restricts oxygen transport and utilization in the body,resulting in functional hypoxia at the tissue level.In clinical practice,a mismatch of cyanotic appearance and oxygen partial pressure usually contributes to the identification of methemoglobinemia.Prompt recognition of characteristic mismatch and accurate diagnosis of sodium nitrite poisoning are prerequisites for the implementation of standardized systemic interventions.CASE SUMMARY A pregnant woman was admitted to the Department of Critical Care Medicine at the First Affiliated Hospital of Harbin Medical University due to consciousness disorders and drowsiness 2 h before admission.Subsequently,she developed vomiting and cyanotic skin.The woman underwent orotracheal intubation,invasive mechanical ventilation(IMV),and correction of internal environment disturbance in the ICU.Her premature infant was born with a higher-than-normal MetHb level of 3.3%,and received detoxification with methylene blue and vitamin C,supplemental vitamin K1,an infusion of fresh frozen plasma,as well as respiratory support via orotracheal intubation and IMV.On day 3 after admission,the puerpera regained consciousness,evacuated the IMV,and resumed enteral nutrition.She was then transferred to the maternity ward 24 h later.On day 7 after admission,the woman recovered and was discharged without any sequelae.CONCLUSION MetHb can cross through the placental barrier.Level of MetHb both reflects severity of the sodium nitrite poisoning and serves as feedback on therapeutic effectiveness. 展开更多
关键词 Sodium nitrite poisoning METHEMOGLOBINEMIA METHEMOGLOBIN Third trimester puerpera Premature infant Placental barrier Methylene blue Case report
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Effects of Standing Time during Pretreatment on the Nitrite Concentration Detected by Spectrophotometric Method
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作者 Yingfei Zeng Juan Hu +2 位作者 Xianglong Bian Qianfeng Xia Tingwei Hu 《Journal of Materials Science and Chemical Engineering》 2024年第2期73-83,共11页
Food safety problems caused by excessive nitrite addition have been frequently reported and the detection of nitrite in food is particularly important. The standing time during the pretreatment of primary sample has a... Food safety problems caused by excessive nitrite addition have been frequently reported and the detection of nitrite in food is particularly important. The standing time during the pretreatment of primary sample has a great influence on the concentration of nitrite tested by spectrophotometric method. In this context, three kinds of food samples are prepared, including canned mustard, canned fish and home-made pickled water. A series of standing times are placed during the sample pretreatments and the corresponding nitrite contents in these samples are detected by spectrophotometric method based on N-ethylenediamine dihydrochloride. This study aims to find out a reasonable standing time during the pretreatment of food sample, providing influence factor for precise detection of nitrite. 展开更多
关键词 Standing Time Spectrophotometric Method nitrite Detection
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The Publication of the Piling Canon in the Late Qing
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作者 LIU Yi 《Cultural and Religious Studies》 2024年第9期566-574,共9页
Piling Canon refers to a woodblock-printed Chinese Buddhist Canon during the late Qing Dynasty.Despite its historical significance,it has received limited attention from the academia,as its discovery took place after ... Piling Canon refers to a woodblock-printed Chinese Buddhist Canon during the late Qing Dynasty.Despite its historical significance,it has received limited attention from the academia,as its discovery took place after the turn of the 21st century.This study explores the background,supervisor,proofreader,engravers,donors,and other factors that contributed to the publication of the Piling Canon.It was supervised by Buddhist monk Qingrong in Changzhou Tianning Monastery from 1908 to 1926,due to the commission of Yang Wenhui.By investigating the historical records in the colophons of Piling Canon,we found that engraving locations are distributed in Hubei,Yangzhou,and Danyang which engravers operated in groups;the majority of donors were found to be individuals and group forms,social fundraising was included as well.It is noteworthy that Sheng Xuanhuai made a significant contribution in terms of funding.Furthermore,the production of the Piling Canon confirms to the commence of Buddhism revival,as Buddhist scriptures in Jiangnan regions were almost destroyed after the Taiping Rebellion.The research shed light on extensive participation of cultural celebrities,diverse donation forms,and excellent engraving,offering a vivid depiction of Buddhist belief and social landscape in Jiangnan region. 展开更多
关键词 Piling canon Buddhist scriptures Tianning Monastery DONORS Jiangnan
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Crosstalk among canonical Wnt and Hippo pathway members in skeletal muscle and at the neuromuscular junction
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作者 Said Hashemolhosseini Lea Gessler 《Neural Regeneration Research》 SCIE CAS 2025年第9期2464-2479,共16页
Skeletal muscles are essential for locomotion,posture,and metabolic regulation.To understand physiological processes,exercise adaptation,and muscle-related disorders,it is critical to understand the molecular pathways... Skeletal muscles are essential for locomotion,posture,and metabolic regulation.To understand physiological processes,exercise adaptation,and muscle-related disorders,it is critical to understand the molecular pathways that underlie skeletal muscle function.The process of muscle contra ction,orchestrated by a complex interplay of molecular events,is at the core of skeletal muscle function.Muscle contraction is initiated by an action potential and neuromuscular transmission requiring a neuromuscular junction.Within muscle fibers,calcium ions play a critical role in mediating the interaction between actin and myosin filaments that generate force.Regulation of calcium release from the sarcoplasmic reticulum plays a key role in excitation-contraction coupling.The development and growth of skeletal muscle are regulated by a network of molecular pathways collectively known as myogenesis.Myogenic regulators coordinate the diffe rentiation of myoblasts into mature muscle fibers.Signaling pathways regulate muscle protein synthesis and hypertrophy in response to mechanical stimuli and nutrient availability.Seve ral muscle-related diseases,including congenital myasthenic disorders,sarcopenia,muscular dystrophies,and metabolic myopathies,are underpinned by dys regulated molecular pathways in skeletal muscle.Therapeutic interventions aimed at preserving muscle mass and function,enhancing regeneration,and improving metabolic health hold promise by targeting specific molecular pathways.Other molecular signaling pathways in skeletal muscle include the canonical Wnt signaling pathway,a critical regulator of myogenesis,muscle regeneration,and metabolic function,and the Hippo signaling pathway.In recent years,more details have been uncovered about the role of these two pathways during myogenesis and in developing and adult skeletal muscle fibers,and at the neuromuscular junction.In fact,research in the last few years now suggests that these two signaling pathways are interconnected and that they jointly control physiological and pathophysiological processes in muscle fibers.In this review,we will summarize and discuss the data on these two pathways,focusing on their concerted action next to their contribution to skeletal muscle biology.However,an in-depth discussion of the noncanonical Wnt pathway,the fibro/a dipogenic precursors,or the mechanosensory aspects of these pathways is not the focus of this review. 展开更多
关键词 canonical Wnt"Wingless-related integration site"pathway beta-catenin(CTNNB1) Hippo pathway MYOGENESIS MYOTUBE neuromuscular junction satellite cell skeletal muscle fiber transcriptional co-activator with PDZ-binding motif(TAZ) T-cell-specific transcription factor/lymphoid enhancer-binding factor(TCF/LEF) TEA domain family member(TEAD) transducin-like enhancer of split(TLE) yes-associated protein 1(YAP1)
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水力条件对CANON工艺颗粒污泥特性的影响研究
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作者 漆磊 《四川环境》 2023年第5期25-30,共6页
为实现自养生物脱氮,采用膨胀颗粒污泥床小试反应器(R1~R3)培养全程自养脱氮工艺(Completely Autotrophic Nitrogen Removal Over Nitrite, CANON)颗粒污泥,考察了不同上升流速、水力剪切力和溶解氧浓度下CANON颗粒污泥浓度和粒径的变... 为实现自养生物脱氮,采用膨胀颗粒污泥床小试反应器(R1~R3)培养全程自养脱氮工艺(Completely Autotrophic Nitrogen Removal Over Nitrite, CANON)颗粒污泥,考察了不同上升流速、水力剪切力和溶解氧浓度下CANON颗粒污泥浓度和粒径的变化规律。结果表明:系统稳定后,污泥浓度呈现出R2>R1>R3,R1、R2成功实现CANON颗粒污泥启动,并且实现了颗粒化,而R3中较高的上升流速、水力剪切力导致系统内污泥易碎裂从而洗出系统,导致R3未能启动成功。 展开更多
关键词 canon工艺 颗粒污泥 剪切力 污泥浓度 污泥粒径
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长期-短期饥饿对CANON工艺启动的影响
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作者 杨综艺 李军 +2 位作者 张凯 高鹏 唐鹏 《中国环境科学》 EI CAS CSCD 北大核心 2023年第7期3429-3437,共9页
采用序批式反应器(SBR)启动全程自养脱氮(CANON)工艺,考察启动过程中长期饥饿胁迫和短期饥饿调控对脱氮效果的影响,对短期饥饿前后功能菌活性进行测试,分析在缩短恢复时间下反复进行短期饥饿对亚硝酸盐氧化菌(NOB)的抑制作用,对CANON启... 采用序批式反应器(SBR)启动全程自养脱氮(CANON)工艺,考察启动过程中长期饥饿胁迫和短期饥饿调控对脱氮效果的影响,对短期饥饿前后功能菌活性进行测试,分析在缩短恢复时间下反复进行短期饥饿对亚硝酸盐氧化菌(NOB)的抑制作用,对CANON启动过程中的不同阶段进行微生物测序,分析群落结构的变化情况.结果表明,长期饥饿后系统在7d恢复运行时,TN去除率(NRE)可达到62.34%.短期饥饿-恢复模式加快了工艺的启动速度,成功将SBR中ΔNO_(3)^(-)-N/ΔNH_(4)^(+)-N控制在0.11左右.在实现启动时,工艺平均氨氮去除率(ARE)超过95%,平均NRE可达79.45%.采用短期饥饿调控前后,NOB活性由91.32mgN/(gVSS·d)降至45.40mgN/(gVSS·d),比厌氧氨氧化活性(SAA)升高至219.25mgN/(gVSS·d),保证了CANON脱氮性能.高通量测序表明,在经历长期饥饿后,好氧氨氧化菌(AerAOB)功能菌Nitrosomonas能够迅速恢复.Candidatus Kuenenia具有抵抗长期饥饿的能力,在7d恢复运行后,相对丰度高达69.04%,在稳定恢复运行中,丰度有所降低,但在工艺启动后丰度达到61.19%,实现了厌氧氨氧化菌(AnAOB)的富集.CANON工艺能够在长期饥饿胁迫中恢复,短期饥饿调控有利于提高工艺效能. 展开更多
关键词 全程自养脱氮(canon) 长期饥饿 功能菌活性 亚硝酸盐氧化菌(NOB)
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Controllable NO Release for Catheter Antibacteria from Nitrite Electroreduction over the Cu-MOF 被引量:3
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作者 Yibo Wang Yutian Qin +4 位作者 Wei Li Yuting Wang Lina Zhu Meiting Zhao Yifu Yu 《Transactions of Tianjin University》 EI CAS 2023年第4期275-283,共9页
Implant-associated infections caused by biomedical catheters severely threaten patients'health.The use of electrochemical control on NO release from benign nitrite equipped in the catheter can potentially resolve ... Implant-associated infections caused by biomedical catheters severely threaten patients'health.The use of electrochemical control on NO release from benign nitrite equipped in the catheter can potentially resolve this issue with excellent biocompatibility.Inspired by nitrite reductase,a Cu-BDC(BDC:benzene-1,4-dicarboxylic acid)catalyst with coordinated Cu(Ⅱ)sites was constructed as a heterogeneous electrocatalyst to control nitrite reduction to nitric oxide for catheter antibacteria.The combined results of in situ and ex situ tests unveil the key function of interconversion between Cu(Ⅱ)and Cu(Ⅰ)species in NO_(2)^(-)reduction to NO.After being incorporated into the actual catheter,the Cu-BDC catalyst exhibits high electrocatalytic activity toward NO_(2)^(-)reduction to NO and excellent antibacteria efficacy with a sterilizing rate of 99.9%,paving the way for the development of advanced metal-organic frameworks(MOFs)electrocatalysts for catheter antibacteria. 展开更多
关键词 Heterogeneous electrocatalysis nitrite electroreduction NO-releasing catheter Antibacterial MOF material
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Sources and transformations of nitrite in the Amundsen Sea in summer 2019 and 2020 as revealed by nitrogen and oxygen isotopes 被引量:2
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作者 Yangjun Chen Jinxu Chen +4 位作者 Yi Wang You Jiang Minfang Zheng Yusheng Qiu Min Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第4期16-24,共9页
In this study,the nitrogen and oxygen isotope compositions of nitrite in the upper 150 m water column of the Amundsen Sea in the summer of 2019 and 2020 were measured to reveal the distribution and transformation of n... In this study,the nitrogen and oxygen isotope compositions of nitrite in the upper 150 m water column of the Amundsen Sea in the summer of 2019 and 2020 were measured to reveal the distribution and transformation of nitrite in the euphotic zone of the Southern Ocean.We found that primary nitrite maxima(PNMs)are widely present in the Amundsen Sea,where the depth of occurrence deepens from east to west and nitrite concentrations increases.Evidence from dual isotopes suggests that the formation of PNMs in all regions of the Amundsen Sea is dominated by ammonia oxidation.More importantly,the nitrogen and oxygen isotope compositions of nitrite in the Amundsen Sea mixed layer are abnormal,and their depth profiles are mirror symmetrical.Isotopic anomalies exhibit spatial variations,with central surface water having the lowest nitrogen isotope composition(−89.9‰±0.2‰)and western surface water having the highest oxygen isotope composition(63.3‰±0.3‰).Isotopic exchange reaction between nitrate and nitrite is responsible for these isotope anomalies,as both nitrogen and oxygen isotopes have large isotopic fractionation and opposite enrichment effects.This proves that isotopic exchange reaction operates extensively in different regions of the Amundsen Sea.Our study highlights the unique role of dual isotopes of nitrite in deepening the understanding of nitrogen cycle.Further studies on ammonia oxidation and isotopic exchange between nitrate and nitrite are warranted in the future to understand their roles in the nitrogen cycle in the Southern Ocean. 展开更多
关键词 nitrogen isotope oxygen isotope nitrite Amundsen Sea
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Solvent extraction and separation of cobalt from leachate of spent lithium-ion battery cathodes with N263 in nitrite media 被引量:3
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作者 Yingnan Yang Yingjie Yang +5 位作者 Chunlin He Yuezhou Wei Toyohisa Fujita Guifang Wang Shaojian Ma Wenchao Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第5期897-907,共11页
To effectively separate and recover Co(Ⅱ) from the leachate of spent lithium-ion battery cathodes,we investigated solvent extraction with quaternary ammonium salt N263 in the sodium nitrite system.NO_(2)^(-)combines ... To effectively separate and recover Co(Ⅱ) from the leachate of spent lithium-ion battery cathodes,we investigated solvent extraction with quaternary ammonium salt N263 in the sodium nitrite system.NO_(2)^(-)combines with Co(Ⅱ) to form an anion [Co(NO_(2))_(3)]^(-),and it is then extracted by N263.The extraction of Co(Ⅱ) is related to the concentration of NO_(2)^(-).The extraction efficiency of Co(Ⅱ) reaches the maximum of99.16%,while the extraction efficiencies of Ni(Ⅱ),Mn(Ⅱ),and Li(Ⅰ) are 9.27%-9.80% under the following conditions:30vol% of N263 and15vol% of iso-propyl alcohol in sulfonated kerosene,the volume ratio of the aqueous-to-organic phase is 2:1,the extraction time is 30 min,and1 M sodium nitrite in 0.1 MHNO_(3).The theoretical stages require for the Co(Ⅱ) extraction are performed in the McCabe–Thiele diagram,and the extraction efficiency of Co(Ⅱ) reaches more than 99.00% after three-stage counter-current extraction with Co(Ⅱ) concentration of 2544mg/L.When the HCl concentration is 1.5 M,the volume ratio of the aqueous-to-organic phase is 1:1,the back-extraction efficiency of Co(Ⅱ)achieves 91.41%.After five extraction and back-extraction cycles,the Co(Ⅱ) extraction efficiency can still reach 93.89%.The Co(Ⅱ) extraction efficiency in the actual leaching solution reaches 100%. 展开更多
关键词 COBALT N263 sodium nitrite EXTRACTION iso-propyl alcohol spent lithium-ion battery
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低C/N比CANON工艺脱氮机制分析
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作者 田亮 黄锐 +1 位作者 杜冬云 吴晨捷 《环境科学与技术》 CAS CSCD 北大核心 2023年第10期104-111,共8页
该文在微氧升流反应器中构建颗粒-絮体污泥体系,以乙酸钠作为碳源,探究了C/N对CANON工艺脱氮效率的影响,并分析了低C/N下该工艺的脱氮机制。当C/N=0.75时,TN和NH_(4)^(+)-N去除率达到了最高值92%和95%。而当C/N从0.75增长至1时,TN和NH_(... 该文在微氧升流反应器中构建颗粒-絮体污泥体系,以乙酸钠作为碳源,探究了C/N对CANON工艺脱氮效率的影响,并分析了低C/N下该工艺的脱氮机制。当C/N=0.75时,TN和NH_(4)^(+)-N去除率达到了最高值92%和95%。而当C/N从0.75增长至1时,TN和NH_(4)^(+)-N去除率分别下降至80%和85%;C/N回调至0.75后,10 d左右反应器性能恢复至91%TN去除率。C/N=0.75时脱氮贡献分析和粒度分布表明AnAOB对NO_(2)^(-)-N的摄取处于优势地位,反应器内主要发生Anammox反应和短程反硝化反应,合适的C/N并不会导致异养菌取代AnAOB的优势地位,且Anammox反应的脱氮贡献在56%~62%之间。 展开更多
关键词 微氧升流反应器 canon工艺 颗粒-絮体污泥 脱氮机制 低C/N
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3-D Gait Identification Utilizing Latent Canonical Covariates Consisting of Gait Features 被引量:1
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作者 Ramiz Gorkem Birdal Ahmet Sertbas 《Computers, Materials & Continua》 SCIE EI 2023年第9期2727-2744,共18页
Biometric gait recognition is a lesser-known but emerging and effective biometric recognition method which enables subjects’walking patterns to be recognized.Existing research in this area has primarily focused on fe... Biometric gait recognition is a lesser-known but emerging and effective biometric recognition method which enables subjects’walking patterns to be recognized.Existing research in this area has primarily focused on feature analysis through the extraction of individual features,which captures most of the information but fails to capture subtle variations in gait dynamics.Therefore,a novel feature taxonomy and an approach for deriving a relationship between a function of one set of gait features with another set are introduced.The gait features extracted from body halves divided by anatomical planes on vertical,horizontal,and diagonal axes are grouped to form canonical gait covariates.Canonical Correlation Analysis is utilized to measure the strength of association between the canonical covariates of gait.Thus,gait assessment and identification are enhancedwhenmore semantic information is available through CCA-basedmulti-feature fusion.Hence,CarnegieMellon University’s 3D gait database,which contains 32 gait samples taken at different paces,is utilized in analyzing gait characteristics.The performance of Linear Discriminant Analysis,K-Nearest Neighbors,Naive Bayes,Artificial Neural Networks,and Support Vector Machines was improved by a 4%average when the CCA-utilized gait identification approachwas used.Asignificant maximumaccuracy rate of 97.8%was achieved throughCCA-based gait identification.Beyond that,the rate of false identifications and unrecognized gaits went down to half,demonstrating state-of-the-art for gait identification. 展开更多
关键词 Gait identification canonical covariates multivariate data analysis gait determinant
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An Update Method of Decision Implication Canonical Basis on Attribute Granulating 被引量:1
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作者 Yanhui Zhai Rujie Chen Deyu Li 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期1833-1851,共19页
Decision implication is a form of decision knowledge represen-tation,which is able to avoid generating attribute implications that occur between condition attributes and between decision attributes.Compared with other... Decision implication is a form of decision knowledge represen-tation,which is able to avoid generating attribute implications that occur between condition attributes and between decision attributes.Compared with other forms of decision knowledge representation,decision implication has a stronger knowledge representation capability.Attribute granularization may facilitate the knowledge extraction of different attribute granularity layers and thus is of application significance.Decision implication canonical basis(DICB)is the most compact set of decision implications,which can efficiently represent all knowledge in the decision context.In order to mine all deci-sion information on decision context under attribute granulating,this paper proposes an updated method of DICB.To this end,the paper reduces the update of DICB to the updates of decision premises after deleting an attribute and after adding granulation attributes of some attributes.Based on this,the paper analyzes the changes of decision premises,examines the properties of decision premises,designs an algorithm for incrementally generating DICB,and verifies its effectiveness through experiments.In real life,by using the updated algorithm of DICB,users may obtain all decision knowledge on decision context after attribute granularization. 展开更多
关键词 Decision context attribute granulating decision implication decision implication canonical basis
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Cohen-Macaulay局部环上的Canonical模
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作者 路姣姣 杨晓燕 《吉林大学学报(理学版)》 CAS 北大核心 2023年第1期61-65,共5页
令(R,m,k)是Cohen-Macaulay局部环,M,N是有限生成R-模.假设N∈ΩCM(R),且Ext_(R)^(1≤i≤d)(M,N)=0,证明HomR(M,N)∈ΩCM(R),并给出有限生成模N是canonical模的条件.
关键词 Cohen-Macaulay局部环 极大Cohen-Macaulay模 canonical模
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Process Optimization and Modeling by Response Surface Methodology of Nitrite Electro-Reduction by Ti/RuO2 + IrO2 Electrode
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作者 Mar Bassine Boye Abdou Khadre Djily Dimé +2 位作者 Adama Diop Cheikhou Kane Modou Fall 《American Journal of Analytical Chemistry》 2023年第12期531-540,共10页
Electrochemical reduction is one of the most suitable methods for the treatment of highly nitrate-contaminated solutions. This work focuses on the optimization of parameters influencing the electrochemical denitrifica... Electrochemical reduction is one of the most suitable methods for the treatment of highly nitrate-contaminated solutions. This work focuses on the optimization of parameters influencing the electrochemical denitrification of water by the Ti/RuO<sub>2</sub> + IrO<sub>2</sub> electrode. The methodological approach used consists in carrying out a series of electrolysis by scrutinizing the reaction selectivity according to the experimental conditions. For this study, the  ions concentrations before and after electrolysis were determined by UV-vis absorption spectroscopy. The results of the process optimization showed that the electrochemical reduction ofis efficient at neutral pH after 120 mn of electrolysis at -100 mA. In contrast to works found in the literature, this study highlighted the process modeling that could open interesting perspectives to develop new treatment methods of polluted waters. 展开更多
关键词 Electrochemical Reduction Water Treatment nitrite Optimization MODELLING
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