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Fabrication of pollution-free coal gangue-based catalytic material utilizing ferrous chloride as activator for efficient peroxymonosulfate activation
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作者 Zhiming Sun Xinlin Wang +3 位作者 Shaoran Jia Jialin Liang Xiaotian Ning Chunquan Li 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第1期103-118,共16页
Novel coal gangue-based persulfate catalyst(CG-FeCl_(2))was successfully synthesized by the means of calcinating under nitrogen atmosphere with the addition of ferrous chloride tetrahydrate(FeCl_(2)·_(4)H_(2)O).T... Novel coal gangue-based persulfate catalyst(CG-FeCl_(2))was successfully synthesized by the means of calcinating under nitrogen atmosphere with the addition of ferrous chloride tetrahydrate(FeCl_(2)·_(4)H_(2)O).The phase transformation of the prepared materials and gas products during the heating process are thoroughly investigated.It is suggested that ferrous chloride participated in the phase transformation and formed Si-O-Fe bonds.And the main gaseous products are H_(2)O,H_(2),and HCl during the heating process.Besides,the ability of CG-FeCl_(2) to activate peroxymonosulfate(PMS)for catalytic degradation of polycyclic aromatic hydrocarbons(PAHs)and phenol was deeply studied.More than 95%of naphthyl,phenanthrene and phenol were removed under optimizied conditions.In addition,1O_(2),·OH,and SO_(4)·−were involved in the CG-FeCl_(2)/PMS system from the free radical scavenging experiment,where 1O_(2) played a major role during the oxidation process.Furthermore,CG-FeCl_(2)/PMS system exhibited superior stability in a relatively wide pH range and the presence of common anion from related degradation experiments.Overall,the novel CG-FeCl_(2) is an efficient and environmentally friendly catalyst,displaying potential application prospect in the field of PAHs and phenol-contaminated wastewater treatment. 展开更多
关键词 Coal gangue Persulfate activation Advanced oxidation processes Polycyclic aromatic hydrocarbons Phenol Ferrous chloride
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Study Progress Analysis of Effluent Quality Prediction in Activated Sludge Process Based on CiteSpace
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作者 Kemeng Xue 《Journal of Water Resource and Protection》 CAS 2024年第6期450-465,共16页
In this paper, CiteSpace, a bibliometrics software, was adopted to collect research papers published on the Web of Science, which are relevant to biological model and effluent quality prediction in activated sludge pr... In this paper, CiteSpace, a bibliometrics software, was adopted to collect research papers published on the Web of Science, which are relevant to biological model and effluent quality prediction in activated sludge process in the wastewater treatment. By the way of trend map, keyword knowledge map, and co-cited knowledge map, specific visualization analysis and identification of the authors, institutions and regions were concluded. Furthermore, the topics and hotspots of water quality prediction in activated sludge process through the literature-co-citation-based cluster analysis and literature citation burst analysis were also determined, which not only reflected the historical evolution progress to a certain extent, but also provided the direction and insight of the knowledge structure of water quality prediction and activated sludge process for future research. 展开更多
关键词 Biological Model Effluent Quality Prediction Activated Sludge process CITESPACE Knowledge Map Co-Citation Cluster Analysis
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Construction Method of Civil Aircraft Airborne⁃system Supplier Development Process System
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作者 PU Youhua LI Lin LI Li 《International Journal of Plant Engineering and Management》 2024年第2期65-77,共13页
Based on the analysis of the development process system status of domestic and foreign civil aircraft airborne system suppliers,this paper proposes the overall construction idea of"a set of civil aircraft process... Based on the analysis of the development process system status of domestic and foreign civil aircraft airborne system suppliers,this paper proposes the overall construction idea of"a set of civil aircraft process system"based on IPD(Integrated product development)in the organization.The development stage,process,activity and task are the logical framework elements of the system construction."Based on process decomposition,vertical stratification,horizontal segmentation,combination of special and common,process customized to tools,role and process integration,giving full consideration to the interface between supplier management and process modules"etc.are the concrete ideas.Moreover,formulate top⁃level system construction standards,implemented by process system management tool platform,so that the process system and development work can be effectively integrated to effectively guide the development work of airborne system suppliers,and meet the quality and airworthiness requirements of civil aircraft development.Through the development application of a certain type of flight control system,the process system and tool platform were verified and optimized in practice. 展开更多
关键词 development process system development assurance process integrated product development(IPD) development stage ACTIVITY
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Comparative study of two biological nitrogen removal processes:A/O process and step-feeding process 被引量:3
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作者 祝贵兵 彭永臻 +1 位作者 王淑莹 马斌 《Journal of Southeast University(English Edition)》 EI CAS 2008年第4期528-531,共4页
Two biological nitrogen removal processes are compared in the aspect of nitrogen removal, process operation and energy saving. Results show that when the returned sludge ratio is 50% of the inflow rate, the step-feedi... Two biological nitrogen removal processes are compared in the aspect of nitrogen removal, process operation and energy saving. Results show that when the returned sludge ratio is 50% of the inflow rate, the step-feeding process achieves over 80% total nitrogen (TN) removal efficiency, but the TN removal efficiency of the A/O process is only 40%. Moreover, filamentous sludge bulking can be well restrained in the step-feeding process. Given the conditions of a returned sludge ratio of 100% and a nitrifying liquor recycle ratio of 200%, the TN removal efficiency is 78.32% in the A/O process, but the sludge volume index (SVI) value increases to 143 mL/g. In the step-feeding process, the SVI is only 94.4 mL/g when the TN removal efficiency reaches 81. 1%. The step-feeding process has distinct advantages over the A/O process in the aspects of practicability, nitrogen removal and operating stability. 展开更多
关键词 activated sludge biological nitrogen removal A/O process step-feeding process efficiency
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Hot compression behavior and processing map of cast Mg-4Al-2Sn-Y-Nd alloy 被引量:6
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作者 王晶 史宝良 杨院生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期626-631,共6页
The plastic flow behavior of a newly developed high ductility magnesium alloy, Mg-4Al-2Sn-Y-Nd, was investigated by hot compression from 200 to 400 ℃ with a strain rate of 1.5×10-3 to 7.5 s-1. The results reveal... The plastic flow behavior of a newly developed high ductility magnesium alloy, Mg-4Al-2Sn-Y-Nd, was investigated by hot compression from 200 to 400 ℃ with a strain rate of 1.5×10-3 to 7.5 s-1. The results reveal that the strain rate sensitivity factor (m) of the alloy is much lower than that of the AZ31 alloy, which implies that the alloy should be more suitable for processing at high strain rate. The constitutive relationship of the alloy deformed at elevated temperature was obtained by plotting the experimental data. The stress exponent of the alloy is 10.33, which reveals that climb-controlled dislocations creep is the dominated deformation mechanism. The processing-map technique was used to determine the practical processing window. The proper deformation temperature and strain rate of the cast alloy were determined as 350-400 ℃ and 0.01-0.03 s-1, respectively. 展开更多
关键词 magnesium alloy uniaxial compression apparent activation energy processing map
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不同加工方式对体外模拟胃肠消化香菇活性物质含量及活性的影响
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作者 姚芬 刘红霞 +5 位作者 范秀芝 史德芳 殷朝敏 高虹 张玉 姚望 《食品科学》 EI CAS 北大核心 2025年第2期183-192,共10页
为研究不同加工方式和处理时间对香菇体外模拟胃肠消化后活性物质含量及体外活性的影响,采用蒸制、煮制、空气炸和烤箱烤制4种方式处理香菇,通过模拟体外胃肠消化后测定消化液中总酚、总黄酮、粗多糖和香菇嘌呤含量及其体外抗氧化、降... 为研究不同加工方式和处理时间对香菇体外模拟胃肠消化后活性物质含量及体外活性的影响,采用蒸制、煮制、空气炸和烤箱烤制4种方式处理香菇,通过模拟体外胃肠消化后测定消化液中总酚、总黄酮、粗多糖和香菇嘌呤含量及其体外抗氧化、降血脂和降血糖活性,并对消化液的体外活性和活性物质含量相关性进行分析。结果表明,消化前,与蒸制、煮制和空气炸处理相比,烤箱烤制更利于香菇中4种活性物质的保留,其中烤制5 min时总酚、总黄酮和粗多糖的含量和烤制15 min时香菇嘌呤的含量相对较高,分别为(222.13±3.57)mg/g、(4.49±0.06)mg/g、(5.57±0.28)g/100 g和(551.31±3.76)mg/100 g。经体外胃肠消化后,烤箱烤制香菇活性物质释放量相对较高,其次为空气炸。除烤箱烤制香菇总黄酮的释放量随烤制时间延长而降低外,其余活性物质释放量与加工时长无明显相关性。蒸制处理后香菇肠消化液的体外活性相对较高,其中,蒸制20 min的香菇肠消化液1,1-二苯基-2-三硝基苯肼自由基清除率和蒸制10 min的2,2′-联氮-双(3-乙基苯并噻唑啉-6-磺酸)(2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid),ABTS)阳离子自由基清除率最高(P<0.05),分别为(88.74±0.34)%和(50.39±0.07)%;而不同加工方式的香菇肠消化液对α-葡萄糖苷酶抑制率无显著差异(P>0.05);蒸制10 min时肠消化液的胰脂肪酶抑制活性相对较强(P>0.05),为(49.42±2.32)%。相关性分析发现,胃消化液的α-葡萄糖苷酶抑制活性与其总酚(P<0.01)和香菇嘌呤(P<0.05)含量呈显著正相关,ABTS阳离子自由基抑制率与其总酚(P<0.05)和粗多糖(P<0.01)含量呈显著正相关;而肠消化液的胰脂肪酶抑制活性与4种活性物质含量均呈极显著负相关(P<0.01)。综上可以看出烤制更有利于活性物质的保留和消化释放,而蒸制更利于改善香菇肠消化液的体外活性。本研究为香菇科学合理的加工提供了指导。 展开更多
关键词 香菇 加工方式 总酚 总黄酮 粗多糖 香菇嘌呤 体外活性
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Carbon dioxide induced degradation of diethanolamine during absorption and desorption processes 被引量:1
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作者 Md.Sakinul Islam Kotaiah Naik Dhanavath +3 位作者 Nhol Kao Pradipto K.Bhattacharjee Brahim Si Ali Rozita Yusoff 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第2期293-302,共10页
Alkanolamines are widely used in the purification of the sourgas sweetening process. During the sour gas absorption process, CO_2 significantly degrades the amine solvent and creates enormous problems for plant operat... Alkanolamines are widely used in the purification of the sourgas sweetening process. During the sour gas absorption process, CO_2 significantly degrades the amine solvent and creates enormous problems for plant operation. In this work, CO_2 induced degradation of aqueous diethanolamine(DEA) solution was conducted in a 1.25 L jacketed glass reactor that functioned as an absorber and stripper at atmospheric conditions. Pure CO_2 was bubbled through the reactor until the solution became saturated. In this study, the concentrations of DEA used were in the range of concentrations between 2 mol·L^(-1) and 4 mol·L^(-1). In the degradation experiment, six generic cycles were conducted for each run. Each cycle was configured with the absorption and desorption of carbon dioxide at 55 ℃ and 100 ℃, respectively. Samples were collected after a predetermined experimental time and analyzed by ion chromatography(IC) to identify unknown ionic degradation products(DGPs). In the IC analysis, three different columns were used for anion, cation and ion exclusion systems, which are Metrosep A Supp 5150/4.0, Metrosep C Supp 4 150/4.0 and Metrosep Organic Acids, respectively. The major identified DGPs of D01 DEA2 M, D02 DEA3 M, and D03 DEA4 M are nitrite, acetate and ammonium. Phosphate product was found in the degraded amine samples which might be due to the contamination of water or chromatographic system. 展开更多
关键词 Degradation Diethanolamine Absorption Stripping Gas sweetening process
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特色发酵类中药竹沥曲炮制工艺研究
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作者 宋佩林 纪奇森 +4 位作者 万兴东 徐海英 寿红斌 胡久平 黄勤挽 《亚太传统医药》 2025年第1期31-37,共7页
目的:依据古代文献记载,恢复竹沥曲发酵工艺,优选竹沥曲的现代发酵工艺。方法:利用单因素试验方法,考察发酵温度、发酵时间、发酵湿度,以每日外观性状、酶活力为评价指标,运用综合加权评分法进行最优工艺参数优选。结果:面粉采用干混法... 目的:依据古代文献记载,恢复竹沥曲发酵工艺,优选竹沥曲的现代发酵工艺。方法:利用单因素试验方法,考察发酵温度、发酵时间、发酵湿度,以每日外观性状、酶活力为评价指标,运用综合加权评分法进行最优工艺参数优选。结果:面粉采用干混法,加水量控制在20~30 g,最佳发酵温度40℃,湿度90%,发酵10 d。结论:筛选出的竹沥曲现代发酵工艺参数具有可行性,工艺稳定可靠,重复性好,与古籍文献记载相符合,可为竹沥曲后续深入研究提供参考。 展开更多
关键词 竹沥曲 发酵工艺 酶活力 发酵类中药
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Effects of Co_3O_4 nanocatalyst morphology on CO oxidation:Synthesis process map and catalytic activity 被引量:6
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作者 曾良鹏 李孔斋 +2 位作者 黄樊 祝星 李宏程 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期908-922,共15页
This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hy... This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hydroxide-carbonate nanoparticles with various morphologies(i.e.,nanorods,nanosheets,and nanocubes) were successfully synthesized,and Co3O4 nanoparticles were obtained by thermal decomposition of the cobalt-hydroxide-carbonate precursors.The results suggest that the cobalt source is a key factor for controlling the morphology of cobalt-hydroxide-carbonate at relatively low hydrothermal temperatures(≤ 140℃).Nanorods can be synthesized in CoCl2 solution,while Co(NO3)2 solution promotes the formation of nanosheets.Further increasing the synthesis temperature(higher than 140 ℃) results in the formation of nanocubes in either Co(NO3)2 or CoCl2 solution.The reaction time only affects the size of the obtained nanoparticles.The presence of CTAB could improve the uniformity and dispersion of particles.Co3O4 nanosheets showed much higher catalytic activity for CO oxidation than nanorods and nanocubes because it has more abundant Co^(3+) on the surface,much higher reducibility,and better oxygen desorption capacity. 展开更多
关键词 Cobalt oxide nanocatalyst Synthesis process map Morphology effect Catalytic activity Carbon monoxide oxidation
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Application of advanced oxidation processes for removing salicylic acid from synthetic wastewaters 被引量:7
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作者 Djalma Ribeiro da Silva Carlos A.Martinez-Huítle 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第1期101-104,共4页
In this study,advanced oxidation processes(AOPs) such as anodic oxidation(AO),UV/H_2O_2 and Fenton processes(FP) were investigated for the degradation of salicylic acid(SA) in lab-scale experiments.Boron-doped diamond... In this study,advanced oxidation processes(AOPs) such as anodic oxidation(AO),UV/H_2O_2 and Fenton processes(FP) were investigated for the degradation of salicylic acid(SA) in lab-scale experiments.Boron-doped diamond(BDD) film electrodes using Ta as substrates were employed for AO of SA.In the case of FP and UV/H_2O_2,most favorable experimental conditions were determined for each process and these were used for comparing with AO process.The study showed that the FP was the most effective process under aci... 展开更多
关键词 Advanced oxidation processes Salicylic acid(SA) Anodic oxidation Ta/BDD Electrocatalytic activity
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Emotion processing in Parkinson's disease: a blood oxygenation level-dependent functional magnetic resonance imaging study 被引量:6
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作者 Mohammed Benzagmout Sa?d Boujraf +8 位作者 Badreeddine Alami Hassane Ali Amadou Halima El Hamdaoui Amine Bennani Mounir Jaafari Ismail Rammouz Mustapha Maaroufi Rabia Magoul Driss Boussaoud 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第4期666-672,共7页
Parkinson's disease is a neurodegenerative disorder caused by loss of dopamine neurons in the substantia nigra pars compacta. Tremor, rigidity, and bradykinesia are the major symptoms of the disease. These motor i... Parkinson's disease is a neurodegenerative disorder caused by loss of dopamine neurons in the substantia nigra pars compacta. Tremor, rigidity, and bradykinesia are the major symptoms of the disease. These motor impairments are often accompanied by affective and emotional dysfunctions which have been largely studied over the last decade. The aim of this study was to investigate emotional processing organization in the brain of patients with Parkinson's disease and to explore whether there are differences between recognition of different types of emotions in Parkinson's disease. We examined 18 patients with Parkinson's disease(8 men, 10 women) with no history of neurological or psychiatric comorbidities. All these patients underwent identical brain blood oxygenation level-dependent functional magnetic resonance imaging for emotion evaluation. Blood oxygenation level-dependent functional magnetic resonance imaging results revealed that the occipito-temporal cortices, insula, orbitofrontal cortex, basal ganglia, and parietal cortex which are involved in emotion processing, were activated during the functional control. Additionally, positive emotions activate larger volumes of the same anatomical entities than neutral and negative emotions. Results also revealed that Parkinson's disease associated with emotional disorders are increasingly recognized as disabling as classic motor symptoms. These findings help clinical physicians to recognize the emotional dysfunction of patients with Parkinson's disease. 展开更多
关键词 Parkinson’s disease EMOTION processing BLOOD OXYGENATION level-dependent functional magnetic resonance imaging brain activation DOPAMINE neural REGENERATION
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Intercross real-time control strategy in alternating activated sludge process for short-cut biological nitrogen removal treating domestic wastewater 被引量:4
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作者 AKIO TAKIGAWA 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第8期957-963,共7页
To develop technically feasible and economically favorable dynamic process control(DPC)strategies for an alternating activated sludge(AAS)system,a bench-scale continuous-flow alternating aerobic and anoxic reactor,per... To develop technically feasible and economically favorable dynamic process control(DPC)strategies for an alternating activated sludge(AAS)system,a bench-scale continuous-flow alternating aerobic and anoxic reactor,performing short-cut nitrogen removal from real domestic wastewater was operated under different control strategies for more than five months.A fixed-time control(FTC) study showed that bending-points on pH and oxidation-reduction potential(ORP)profiles accurately coincided with the major biologic... 展开更多
关键词 alternating activated sludge process CONTINUOUS-FLOW real-time control NITRIFICATION
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Effects of compressing and remelting in SIMA processing on semi-solid structure evolution of an Al-Zn wrought alloy 被引量:6
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作者 LIUChangming ZOUMaohua 《Rare Metals》 SCIE EI CAS CSCD 2003年第3期185-191,共7页
Structure evolution of an Al-Zn wrought alloy in remelting processing in thestrain induced melt activated (SIMA) serai-solid procedure was observed, and effects of factors, theremelting temperature, the holding time, ... Structure evolution of an Al-Zn wrought alloy in remelting processing in thestrain induced melt activated (SIMA) serai-solid procedure was observed, and effects of factors, theremelting temperature, the holding time, and the compression strain, on structures and grain sizesof the alloy were investigated. The results show that (1) the proper temperature of remelting is inthe range of 610 to 615℃; (2) the grain size in specimen with greater compression strain is smallerthan that with smaller compression strain in condition of the same remelting temperature andholding time, and the grain size in local area with great local equivalent strain is smaller thanthat with small one; (3) liquid occurs in form of cluster in matrix during remelting and itsquantity increases with remelting time increasing; liquid in specimen with great compression strainoccurs earlier than that with small one, and quantity of liquid in the center of specimen withgreater local equivalent strain is greater than that in the two ends of it; (4) distortion energyafter deforming in matrix of the alloy is the significant factor to activate melting of matrix atlocal area with great local equivalent strain. 展开更多
关键词 semi-solid structure evolution strain induced melt activated processing semi-solid remelting Al-Zn alloy
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Determination of dynamic recrystallization parameter domains of Ni80A superalloy by enhanced processing maps 被引量:9
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作者 Guo-zheng QUAN Qiao LIU +2 位作者 Jiang ZHAO Wei XIONG Rui-ju SHI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第7期1449-1464,共16页
The determination of intrinsic deformation parameters inducing grain refinement mechanism of dynamic recrystallization (DRX) contributes to the relative forming process design. For Ni80A superalloy, the processing map... The determination of intrinsic deformation parameters inducing grain refinement mechanism of dynamic recrystallization (DRX) contributes to the relative forming process design. For Ni80A superalloy, the processing maps were constructed by the derivation of the stress-strain data coming from a series of isothermal compression tests at temperatures of 1273^-1473 K and strain rates of 0.01-10 s^-1. According to the processing maps and microstructural validation, the deformation parameter windows with DRX mechanism were separated in an innovative deformation mechanism map. In addition, the deformation activation energy representing deformation energy barrier was introduced to further optimize such windows. Finally, the enhanced processing maps were constructed and the parameter domains corresponding to DRX mechanism and lower deformation barrier were determined as follows: at ε=0.3, domains: 1296-1350 K, 0.056-0.32 s^-1 and 1350-1375 K, 0.035-0.11 s^-1;at ε=0.5, domains: 1290-1348 K, 0.2-0.5 s^-1 and 1305-1370 K, 0.035-0.2 s^-1;at ε=0.7, domains: 1290-1355 K, 0.042-0.26 s^-1;at ε=0.9, domains: 1298-1348 K, 0.037-0.224 s^-1. 展开更多
关键词 nickel-based superalloy deformation activation energy processing map dynamic recrystallization
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Comparison of heavy metal removal efficiencies in four activated sludge processes 被引量:3
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作者 杨军 高定 +3 位作者 陈同斌 雷梅 郑国砥 周小勇 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3788-3794,共7页
The removal efficiencies of heavy metals(As, Cr, Cu, Ni, Pb and Zn) were investigated in the 17 operating municipal wastewater treatment plants(WWTPs) and compared with those in four main activated sludge processes. S... The removal efficiencies of heavy metals(As, Cr, Cu, Ni, Pb and Zn) were investigated in the 17 operating municipal wastewater treatment plants(WWTPs) and compared with those in four main activated sludge processes. Significant differences of heavy metal removal efficiencies were observed among four activated sludge processes. The removal efficiency for As(75.5%) in the oxidation ditch(OD) process is significantly higher than that in the conventional activated sludge(CAS) process(38.6%) or sequencing batch reactor(SBR) process(51.4%). The mean removal efficiencies for Cu and Ni in the OD process are 90.5% and 46.7%, respectively, while low mean removal efficiencies are observed for Cu(69.9%) and Ni(16.5%), respectively, in the SBR process. The removal efficiencies for Cu and Ni in the OD process are significantly higher than those in the anaerobic-anoxic-oxic(A2-O) process. These results highlight the differences of removal efficiencies for heavy metals in different processes and should be considered when selecting a wastewater treatment process. 展开更多
关键词 WASTEWATER heavy metal removal efficiency treatment process activated sludge processes
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Vacuum pressure swing adsorption process for coalbed methane enrichment 被引量:6
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作者 Bo Lu Yuanhui Shen +2 位作者 Zhongli Tang Donghui Zhang Gaofei Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第4期264-280,共17页
The enrichment of low concentration coalbed methane using adsorption process with activated carbon adsorbent was studied in this work.Adsorption isotherms of methane,nitrogen and carbon dioxide on activated carbon wer... The enrichment of low concentration coalbed methane using adsorption process with activated carbon adsorbent was studied in this work.Adsorption isotherms of methane,nitrogen and carbon dioxide on activated carbon were measured by volumetric method,meanwhile a series of breakthrough tests with single component,binary components and three components feed mixture has been performed for exploring dynamic adsorption behaviors.Moreover,a rigorous mathematical model of adsorption bed containing mass,energy,and momentum conservation equation as well as dualsite Langmuir model with the Linear driving force model for gassolid phase mass transfer has been proposed for numerical modeling and simulation of fixed bed breakthrough process and vacuum pressure swing adsorption process.Furthermore,the lumped mass transfer coefficient of methane,nitrogen and carbon dioxide on activated carbon adsorbent has been determined to be 0.3 s^(-1),1.0 s^(-1) and 0.06 s^(-1) by fitting the breakthrough curves using numerical calculation.Additionally,a six bed VPSA process with twelve step cycle sequence has been proposed and investigated for low concentration coalbed methane enrichment.Results demonstrated that the methane molar fraction in feed mixture ranged from 10%to 50%could be enriched to 32.15%to 88.75%methane in heavy product gas with a methane recovery higher than 83%under the adsorption pressure of 3 bar(1 bar=105 Pa)and desorption pressure of 0.1 bar.Energy consumption of this VPSA process was varied from 0.165 k·W·h·m^(-3) CH_(4)to 0.649 k·W·h·m^(-3) CH_(4).Finally,a dualstage VPSA process has been successfully developed to upgrade a low concentration coalbed methane containing 20%methane to a target product gas with methane purity higher than 90%,meanwhile the total methane recovery was up to 98.71%with a total energy consumption of 0.504 k·W·h·m^(-3)CH_(4). 展开更多
关键词 oalbed methane enrichment VPSA process Activated carbon Numerical modeling
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Triple-Helix Structured Model Based on Problem-Knowledge-Solution Co-evolution for Innovative Product Design Process 被引量:4
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作者 Qian Hui Yan Li +1 位作者 Ye Tao Hongwei Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第6期49-63,共15页
A design problem with deficient information is generally described as wicked or ill-defined.The information insufficiency leaves designers with loose settings,free environments,and a lack of strict boundaries,which pr... A design problem with deficient information is generally described as wicked or ill-defined.The information insufficiency leaves designers with loose settings,free environments,and a lack of strict boundaries,which provides them with more opportunities to facilitate innovation.Therefore,to capture the opportunity behind the uncertainty of a design problem,this study models an innovative design as a composite solving process,where the problem is clarified and resolved from fuzziness to satisfying solutions by interplay among design problems,knowledge,and solutions.Additionally,a triple-helix structured model for the innovative product design process is proposed based on the co-evolution of the problem,solution,and knowledge spaces,to provide designers with a distinct design strategy and method for innovative design.The three spaces interact and co-evolve through iterative mappings,including problem structuring,knowledge expansion,and solution generation.The mappings carry the information processing and decision-making activities of the design,and create the path to satisfying solutions.Finally,a case study of a reactor coolant flow distribution device is presented to demonstrate the practicability of this model and the method for innovative product design. 展开更多
关键词 Innovative design Problem-knowledge-solution co-evolution Design activity Design process Product design
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Enhanced biological nutrient removal in modified carbon source division anaerobic anoxic oxic process with return activated sludge pre-concentration 被引量:7
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作者 鲁骎 毋海燕 +1 位作者 李昊岩 杨殿海 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第6期1027-1034,共8页
A pilot-scale modified carbon source division anaerobic anoxic oxic(AAO) process with pre-concentration of returned activated sludge(RAS) was proposed in this study for the enhanced biological nutrient removal(BNR) of... A pilot-scale modified carbon source division anaerobic anoxic oxic(AAO) process with pre-concentration of returned activated sludge(RAS) was proposed in this study for the enhanced biological nutrient removal(BNR) of municipal wastewater with limited carbon source. The influent carbon source was fed in step while a novel RAS pre-concentration tank was adopted to improve BNR efficiency, and the effects of an influent carbon source distribution ratio and a RAS pre-concentration ratio were investigated. The results show that the removal efficiency of TN is mainly influenced by the carbon source distribution ratio while the TP removal relies on the RAS pre-concentration ratio. The optimum carbon source distribution ratio and RAS pre-concentration ratio are 60% and 50%, respectively, with an inner recycling ratio of 100% under the optimum steady operation of pilot test, reaching an average effluent TN concentration of 9.8 mg·L-1with a removal efficiency of 63% and an average TP removal efficiency of 94%. The mechanism of nutrient removal is discussed and the kinetics is analyzed. The results reveal that the optimal carbon source distribution ratio provides sufficient denitrifying carbon source to each anoxic phase, reducing nitrate accumulation while the RAS pre-concentration ratio improves the condition of anaerobic zone to ensure the phosphorus release due to less nitrate in the returned sludge. Therefore, nitrifying bacteria, denitrifying bacteria and phosphorus accumulation organisms play an important role under the optimum condition, enhancing the performance of nutrient removal in this test. 展开更多
关键词 Modified AAO process Carbon source distribution ratio Returned activated sludge pre-concentration Biological nutrient removal
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A new type of Shipboard Meteorological Satellite Receiving-processing System 被引量:2
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作者 Xie Simei Hao Chunjiang +4 位作者 Zou Bin Jing Qiyi Liao Xiaohong Sheng Xiaowen Zhang Canrong (1. National Research Center for Marine Environment Forecasts, Beijing 100081, China 2, Second Institute of China Aerospace Corporation 3. Beijing Chuanyi Electric Compan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2000年第1期35-46,共12页
The Shipboard Meteorological Satellite Receiving-processing System (SMSRPS) is specially developed for the navigation meteorological safeguard of the Antarctic exploration ship over the sea ice area of the forth Ocean... The Shipboard Meteorological Satellite Receiving-processing System (SMSRPS) is specially developed for the navigation meteorological safeguard of the Antarctic exploration ship over the sea ice area of the forth Ocean. This system can suit to the climate environment of very high temperature high moisture and very low temperature - supersaturation; it has a self-protection ability to against the hurricane - force wind over force 12 and the strong vibration during icebreaking, as well as strong magnetic disturbance. It has two sets of receiving-imagery processing systems for polar orbit low-resolution and quasi-stationary high-solution satellites. The key creation Points of this system are as follows: 1. the active gyro-control stabilization platform and a mixed mounting system of three rotating a - B and x -- y axes are used. It solved the tracing difficulties both in the low elevation angle and very high elevation angle of polar-orbit satellite, even in the status of ship moving with continuously changing its poition, direction and ship roll and pitch. 2. Imagery processing subsystem. The newest BORLAND-- DELPHI language and PASCAL language pro gramming software are used under WINDOWS 95 environment. It has a dynamic positioning nested-grid system and electric mapping grid data system. It can show the latitude-longitude of any point on the map, and marks any object such as ship, station or island, and draws the route. It can monitor cloud and temperature, forest fire, anomalous change of ocean and land. It can output satellite cloud maps of 24 bit with very high clarity. This system is very advanced in technique for the whole structure with the features of small volume, light weight and very low cost. It suits to very bad climate and ocean environment. Its imagery process ing system has complete functions with high resolution and being very easy to operate. It is not only suit to land use, but also and specially to all kinds of ship over the sea. It can be extended to domestic and international use. This system played a very important role in the 14th Chinese Antarctic Exploration Navigation, and was introduced a broad attention paid by Chinese newspapers and TV Stations. 展开更多
关键词 Shipboard Meteorological Satellite Receiving-processing System imagery processing system active gyro-control platform
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Freeze-thaw processes of active-layer soils in the Nanweng'he River National Natural Reserve in the Da Xing'anling Mountains,northern Northeast China 被引量:2
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作者 RuiXia He HuiJun Jin +2 位作者 XiaoLi Chang YongPing Wang LiZhong Wang 《Research in Cold and Arid Regions》 CSCD 2018年第2期104-113,共10页
The active-layer soils overlying the permafrost are the most thermodynamically active zone of rock or soil and play important roles in the earth-atmosphere energy system. The processes of thawing and freezing and thei... The active-layer soils overlying the permafrost are the most thermodynamically active zone of rock or soil and play important roles in the earth-atmosphere energy system. The processes of thawing and freezing and their associated complex hydrothermal coupling can significantly affect variation in mean annual temperatures and the formation of ground ice in permafrost regions. Using soil-temperature and-moisture data obtained from the active layer between September 2011 and October 2014 in the permafrost region of the Nanweng'he River in the Da Xing'anling Mountains, the freeze-thaw characteristics of the permafrost were studied. Based on analysis of ground-temperature variation and hydrothermal transport characteristics, the thawing and freezing processes of the active layer were divided into three stages:(1) autumn-winter freezing,(2) winter freeze-up, and(3) spring-summer thawing. Variations in the soil temperature and moisture were analyzed during each stage of the freeze-thaw process, and the effects of the soil moisture and ground vegetation on the freeze-thaw are discussed in this paper. The study's results show that thawing in the active layer was unidirectional, while the ground freezing was bidirectional(upward from the bottom of the active layer and downward from the ground surface).During the annual freeze-thaw cycle, the migration of soil moisture had different characteristics at different stages. In general, during a freezing-thawing cycle, the soil-water molecules migrate downward, i.e., soil moisture transports from the entire active layer to the upper limit of the permafrost. In the meantime, freeze-thaw in the active layer can be significantly affected by the soil-moisture content and vegetation. 展开更多
关键词 Nanweng'he RIVER NATIONAL NATURAL RESERVE ACTIVE LAYER freeze-thawing processes moisture content vegetation effect
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