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Fabrication of ceramic layer on an Al-Si alloy by MAO process 被引量:2
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作者 SONG Xigui, BIAN Xiufang, QI Xiaogang, and ZHANG JunyanKey Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University (Southern Campus), Jinan 250061, China (Received 2002-04-11) 《Rare Metals》 SCIE EI CAS CSCD 2003年第2期103-106,共4页
The MAO (Micro-Arc Oxidation) process is applied to a eutectic Al-Si alloy(Al-12.0 percent Si-l.0 percent Cu-0.9 percent Mg (mass fraction)). The oxide ceramic layer wasfabricated with about 220 mum thickness and 3000... The MAO (Micro-Arc Oxidation) process is applied to a eutectic Al-Si alloy(Al-12.0 percent Si-l.0 percent Cu-0.9 percent Mg (mass fraction)). The oxide ceramic layer wasfabricated with about 220 mum thickness and 3000 Hv micro-hardness. By XRD (X-ray diffractometry)and DSC (differential scanning calorimetry) analyses, the oxide layer consists of amorphous Al_2O_3,which is distinct from the results reported by the other researchers. The SEM photographs of suchlayer show that the layer is fixed tightly on the substrate alloy. So this alloy can he used in thehigh temperature and friction environment alter it is treated with such process. 展开更多
关键词 metal material ceramic layer mao process Al-Si alloy
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β-二酮钛配合物/MAO催化合成间规聚苯乙烯及其热性能 被引量:9
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作者 阎卫东 刘立新 +3 位作者 姜涛 李丹 周鼐 胡友良 《应用化学》 CAS CSCD 北大核心 2001年第2期116-119,共4页
以β-二酮钛配合物 /MAO催化苯乙烯间规聚合 . 80℃ ,β-二酮钛浓度为 4 .3× 1 0 - 4 mol/L,β-二酮钛与 MAO的物质的量比为 50 0时 ,聚合活性为 6.2× 1 0 5 g/( mol· h) .该催化剂对温度的稳定性较高 .所得聚合物的熔点... 以β-二酮钛配合物 /MAO催化苯乙烯间规聚合 . 80℃ ,β-二酮钛浓度为 4 .3× 1 0 - 4 mol/L,β-二酮钛与 MAO的物质的量比为 50 0时 ,聚合活性为 6.2× 1 0 5 g/( mol· h) .该催化剂对温度的稳定性较高 .所得聚合物的熔点在 2 67℃左右 .测定了所得间规聚苯乙烯的基本热性能 . 展开更多
关键词 间规聚苯乙烯 苯乙烯 间规聚合 β-二酮钛配合物 热性能 mao 催化聚合
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α-萘基丁二亚胺氯化镍/MAO制备双(宽)峰聚乙烯 被引量:11
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作者 艾娇艳 刘新星 +1 位作者 祝方明 林尚安 《高分子学报》 SCIE CAS CSCD 北大核心 2005年第2期240-243,共4页
合成了一种新型α 二亚胺镍配合物———α 萘基丁二亚胺氯化镍 ,此配合物作为催化剂在MAO的活化下催化乙烯聚合得到支化聚乙烯 ,聚合活性高达 7 18× 10 5gPE molNi·h ,1 3C NMR、FTIR测试结果表明制备的聚乙烯含有末端双键 ;... 合成了一种新型α 二亚胺镍配合物———α 萘基丁二亚胺氯化镍 ,此配合物作为催化剂在MAO的活化下催化乙烯聚合得到支化聚乙烯 ,聚合活性高达 7 18× 10 5gPE molNi·h ,1 3C NMR、FTIR测试结果表明制备的聚乙烯含有末端双键 ;GPC结果表明所制备的聚乙烯分子量呈双 (宽 )峰分布 ,其原因有两个 ,一是此催化剂能产生分子量较低的α 烯烃 ,在聚合过程中一部分α 烯烃会“就地”与乙烯原位共聚形成分子量较高的聚合物 ,二是此催化剂存在立体异构体 ,而不同异构体在MAO活化下形成的活性中心的配位环境不同 ,因而得到的聚乙烯的分子量也不同 .研究了聚合温度、聚合压力、铝镍摩尔比 (nAl nNi)对催化活性、聚乙烯分子量、支化度的影响 .聚乙烯的分子量随聚合温度的升高而下降 ,支化度增大 ,熔点则降低 . 展开更多
关键词 mao 氯化镍 制备 萘基 α-烯烃 聚合温度 分子量 Α-二亚胺 支化聚乙烯 立体异构体 催化剂 镍配合物 乙烯聚合 聚合活性 ^13C 原位共聚 聚合过程 配位环境 活性中心 催化活性 支化度 NMR GPC 聚合物 摩尔比 活化
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铁系双亚胺基吡啶配合物/MAO体系催化乙烯齐聚制备α-烯烃中试研究 被引量:1
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作者 郑来昌 王如文 +1 位作者 蒋斌波 李化毅 《润滑油》 CAS 2019年第1期42-47,共6页
以乙酰丙酮铁和双亚胺基吡啶类配体组成的配合物为催化剂,甲基铝氧烷(MAO)为助催化剂,以混合己烷为溶剂,在0. 3 m3高压反应釜中开展了乙烯齐聚制备α-烯烃的中试研究,考察了其放大效应,重点对釜内压力、温度、乙烯瞬时流量、累积流量和... 以乙酰丙酮铁和双亚胺基吡啶类配体组成的配合物为催化剂,甲基铝氧烷(MAO)为助催化剂,以混合己烷为溶剂,在0. 3 m3高压反应釜中开展了乙烯齐聚制备α-烯烃的中试研究,考察了其放大效应,重点对釜内压力、温度、乙烯瞬时流量、累积流量和催化剂活性的变化情况进行了考察,通过对齐聚产物进行离心分离和精馏分离,确定出了合理的工艺路线和工艺条件。结果表明,该催化剂活性高达7. 7×107~1. 03×108g/mol·h·MPa,合成的液相产品中,C6~C24α-烯烃含量为77%~81%,α-烯烃选择性大于97%,与实验室水平基本相当。 展开更多
关键词 双亚胺基吡啶 乙酰丙酮铁 mao 乙烯齐聚 Α-烯烃 中试研究
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双亚胺基吡啶/氯化亚铁/MAO催化乙烯齐聚制备α-烯烃研究 被引量:1
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作者 王如文 郑来昌 +2 位作者 赵丹平 杨小辉 杨克 《石油化工应用》 CAS 2016年第11期130-133,共4页
本研究以双亚胺基吡啶/氯化亚铁/MAO为催化体系,开展乙烯齐聚制备α-烯烃的工艺研究。考察了溶剂、温度、压力、主催化剂、助催化剂用量对反应速率和活性的影响,确定了实验室反应工艺条件,催化剂活性稳定在(1.0~1.5)×108g产品/(... 本研究以双亚胺基吡啶/氯化亚铁/MAO为催化体系,开展乙烯齐聚制备α-烯烃的工艺研究。考察了溶剂、温度、压力、主催化剂、助催化剂用量对反应速率和活性的影响,确定了实验室反应工艺条件,催化剂活性稳定在(1.0~1.5)×108g产品/(mol催化剂·h)。 展开更多
关键词 双亚胺基吡啶 mao 乙烯齐聚 制备 Α-烯烃
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An exemplification of the Evolving Process by Studying the Chinese Character Mao
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作者 周吉红 伍光琴 《海外英语》 2013年第21期294-296,共3页
This paper tries to demarcate the evolving process of decategorization into three periods and exemplify it by studying the Chinese character Mao.The exemplification shows the correctness of the demarcation.
关键词 DECATEGORIZATION attributes demarcate Chinese CHAR
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On the horizontal distribution of algal-bloom in Chaohu Lake and its formation process 被引量:7
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作者 Yuan-Ying Chen Qing-Quan Liu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第5期656-666,共11页
Based on the remote sensing images of algae, the present work analyzes the horizontal distribution characteristics of algal blooms in Chaohu Lake, China, which also reveals the frequency of algal blooms under differen... Based on the remote sensing images of algae, the present work analyzes the horizontal distribution characteristics of algal blooms in Chaohu Lake, China, which also reveals the frequency of algal blooms under different wind directions. Further, an unstructured-grid, three-dimensional finite-volume coastal ocean model (FVCOM) is applied to investigate the wind-induced currents and the transport pro- cess to explain the reason why algal blooms occur at the detected places. We first deduce the primary distribution of biomass from overlaid satellite images, and explain the formation mechanism by analyzing the pollution sources, and simulating the flow field and transportation process under prevailing wind over Chaohu Lake. And then, we consider the adjustment action of the wind on the corresponding day and develop a two-time scale approach to describe the whole formation process of algae horizontal distribution in Chaohu Lake. That is, on the longer time scale, i.e., during bloom season, prevailing wind determines the primary distribution of biomass by inducing the characteristic flow field; on the shorter time scale, i.e., on the day when bloom occurs, the wind force adjusts the primary distribution of biomass to form the final distribution of algal bloom. 展开更多
关键词 Chaohu Lake Algal bloom Horizontal distri- bution - Wind-driven current Two-time scale process
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Modal identification based on Hilbert-Huang Transform of structural response with S VD preprocessing 被引量:7
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作者 Min Zheng Fan Shen Yuping Dou Xiaoyan Yan College of Civil Aviation,Nanjing University of Aeronautics and Astronautics,210016 Nanjing. China 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第6期883-888,共6页
In recent years, Empirical mode decomposition and Hilbert spectral analysis have been combined to identify system parameters. Singular-Value Decomposition is pro- posed as a signal preprocessing technique of Hilbert-H... In recent years, Empirical mode decomposition and Hilbert spectral analysis have been combined to identify system parameters. Singular-Value Decomposition is pro- posed as a signal preprocessing technique of Hilbert-Huang Transform to extract modal parameters for closely spaced modes and low-energy components. The proposed method is applied to a simulated airplane model built in Automatic Dynamic Analysis of Mechanical Systems software. The results demonstrate that the identified modal parameters are in good agreement with the baseline model. 展开更多
关键词 Modal identification . Hilbert-Huang Transforms - Singular-value decomposition . Signal processing
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The EVA plastic film for V-process and steel castings by V-process in China 被引量:1
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作者 Ye Shengping Wang Lei Liu Dehan 《China Foundry》 SCIE CAS 2008年第2期77-81,共5页
EVA plastic film is the key material for V-process. Through decades of research, special EVA film for V-process has been produced. The film has adequate elongation; its maximum is about 800% in longitudinal direction ... EVA plastic film is the key material for V-process. Through decades of research, special EVA film for V-process has been produced. The film has adequate elongation; its maximum is about 800% in longitudinal direction and 750% in transversal direction. The single width of the film is 2.8 m and the double width is 5.6 m, which is the widest sheet film for V-process in China. Sheets with different thickness ranging from the thickest 0.35 mm to the thinnest 0.08 mm can meet different demands in China. The film can be used not only for V-process of iron castings, but also for the manganese steel railway frog, steel rocking support and side frame castings for train and the steel bridge box for engine truck. 展开更多
关键词 V - process EVA plastic film steel castings
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Risk Assessment M ode of Sale-Leaseback——Based on Fuzzy Analytic Hierarchy Process 被引量:1
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作者 陈俊宇 李智 张佳煌 《Journal of Donghua University(English Edition)》 EI CAS 2013年第4期343-348,共6页
Sale-leaseback is paid special focus on for its great application in China in recent years.By giving a detailed analysis,an analysis of the features of sale-leaseback and a study of the risks of it are given in this p... Sale-leaseback is paid special focus on for its great application in China in recent years.By giving a detailed analysis,an analysis of the features of sale-leaseback and a study of the risks of it are given in this paper.Then a quantitative analysis of commercial real estate sale-leaseback is carried out.The scientific theoretical analysis is provided in this paper for risk assessment in commercial real estate sale-leaseback mode in China.An effective approach is put forward for sale-leaseback project evaluation and prevention of risk.A useful means is given to supervise commerciai real estate sale-leaseback mode for relevant departments and a certain contribution is made to a further sound development of commercial real estate sale-leaseback mode. 展开更多
关键词 sale-leaseback fuzzy analytic hierarchy process(FAHP) risk assessment modeCLC number:F830.9Document code:AArticle ID:1672-5220(2013)04-0343-06
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The Application of Air-flow to the Technological Process of Chemical Fiber
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作者 崔启亮 陈明 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期112-114,共3页
The air-flow’s states and ways acted on the technological process of chemical fiber are summed up, which includes chip drying, spinning quenching as well as airjet texturing (air texturing, tangling texturing and bul... The air-flow’s states and ways acted on the technological process of chemical fiber are summed up, which includes chip drying, spinning quenching as well as airjet texturing (air texturing, tangling texturing and bulked continuous filament (BCF)),and the effect of air-flow on the process and quality of chemical fiber is studied,and the action of mechanics and heat on the bulked continuous filament are calculated. 展开更多
关键词 AIR - flow CHEMICAL FIBER TECHNOLOGICAL process
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Green fuel from coal via Fischer-Tropsch process: scenario of optimal condition of process and modelling
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作者 Hossein Atashil Somayyeh Veiskarami 《International Journal of Coal Science & Technology》 EI 2018年第2期230-243,共14页
Extracting, transportation and the using from fossil fuels can damage to the hydrosphere, the biosphere and the Earth's atmosphere. But humans always need to this valuable substance. The production of oil derivatives... Extracting, transportation and the using from fossil fuels can damage to the hydrosphere, the biosphere and the Earth's atmosphere. But humans always need to this valuable substance. The production of oil derivatives by means of forest waste and coal through the Fischer-Tropsch process is an appropriate solution for the cleanliness of all parts of the environment. For the production of favorite products by the synthesis of Fischer-Tropsch, the performance of the catalyst under different operating conditions should be predictable. For this reason, in this paper, eight mathematical models were determined for the selectivity of five products of methane, light hydrocarbons, gasoline, diesel and wax based on three factors of reduction temperature, time on stream, and He/CO ratio inlet gas on iron-based catalyst. The results showed that the reduction temperature factor had the most effective on the selectivity of hydrocarbon products, exception diesel, so that the increase of the reduction temperature led to increase of the selectivity of methane, light hydrocarbons, gasoline and reduce of the degree of selectivity of the wax and vice versa. For the diesel selectivity, factor of the He/CO ratio inlet gas was the most effective than other factors. 展开更多
关键词 Fischer-Tropsch process - Selectivity model Iron based catalyst BIOMASS Oil derivatives
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An analysis on El Nino processes during 1949-1987
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《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第2期219-226,共8页
-In this paper, the outset, evolution and intensity of El Nino were analyzed. Different features were found in each El Nino process. The El Nino of 1986 was also analyzed and outlined.
关键词 Nino Pro An analysis on El Nino processes during 1949-1987 SST El
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The Evolutionary History of Ore-forming Processes of Metallic Ore Deposits in Northern Guangxi
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作者 Chen Yuchuan, Mao Jinwen and Wang Ping’an Chinese Academy of Geological Sciences, Beijing Fei Zhenbi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1995年第2期155-170,共16页
The northern Guangxi region is an important rare metal, rare earth metal and polymetallic metallogenic province. In the region there exist five metallogenic series and two metallogenic subseries, whose metallogenesis ... The northern Guangxi region is an important rare metal, rare earth metal and polymetallic metallogenic province. In the region there exist five metallogenic series and two metallogenic subseries, whose metallogenesis shows features of polycyclic spiral evolution throughout the geological history. As far as various cycles are concerned, mantle-derived ore substances were reduced while crust-derived ore substances increased from early to late timesfin the whole geological evolutionary history, mantle-derived substances decreased gradually while crust-derived ones increased. Meanwhile ore element associations became more and more varied. In terms of space, mineralization migrated from the old basement outwards, i.e. from west to east during the Precambrian, and from north to south during the Phanerozoic, and again from east to west during the Yanshanian. 展开更多
关键词 metallogenic series evolutionary history of ore - forming processes metallogenic model rare metal- nonferrous metal deposit
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STUDY OF PREPARATION AND PROPERTY OF YBa_2Cu_3O_(7-δ)-Ag_x COMPOSITE SUPERCONDUCTORS PREPARED BY SOL-GEL PROCESS
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作者 袁启华 唐福龙 +1 位作者 佟钰 袁润章 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1996年第1期47-51,共5页
YBa2Cu3O7-δ-Agx composite superconductors were prepared by hybrid sintering process using YBa2Cu3O7-δ-Agx ultrafine powder and Ag2O finepower, which were prepared by sol-gel process and precipitation process respect... YBa2Cu3O7-δ-Agx composite superconductors were prepared by hybrid sintering process using YBa2Cu3O7-δ-Agx ultrafine powder and Ag2O finepower, which were prepared by sol-gel process and precipitation process respectively. The effect of the Ag content on superconducting crictical transition temperature of YBa2Cu3O7-δ-Agx was not evident as long as YBa2Cu3O7-δ-Agx can form continuous network. But Ag can increase superconduction crictical current and density of the composite superconductors. The normal state (i.e. non-superconducting state at room temperature) resistivity shows a percolation threshold at 20%-30% Ag, whereas the superconducting net-work shows a percolationthreshold at 70% -80% Ag. 展开更多
关键词 YBa2Cu3O7-δ-Agx superconductors sol-gel process.
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A Comparative Analysis of the New -3(-n) - 1 Remer Conjecture and a Proof of the 3n + 1 Collatz Conjecture
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作者 Mike Remer 《Journal of Applied Mathematics and Physics》 2023年第8期2216-2220,共5页
This scientific paper is a comparative analysis of two mathematical conjectures. The newly proposed -3(-n) - 1 Remer conjecture and how it is related to and a proof of the more well known 3n + 1 Collatz conjecture. An... This scientific paper is a comparative analysis of two mathematical conjectures. The newly proposed -3(-n) - 1 Remer conjecture and how it is related to and a proof of the more well known 3n + 1 Collatz conjecture. An overview of both conjectures and their respective iterative processes will be presented. Showcasing their unique properties and behavior to each other. Through a detailed comparison, we highlight the similarities and differences between these two conjectures and discuss their significance in the field of mathematics. And how they prove each other to be true. 展开更多
关键词 -3(-n) - 1 Remer Conjecture 3n + 1 Collatz Conjecture Comparative Analysis PROOF Natural Numbers Integer Sequences Factorial processes Par-tial Differential Equations Bounded Values Collatz Conjecture Collatz Algo-rithm Collatz Operator Collatz Compliance And Mathematical Conjectures
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铁系双亚胺基吡啶配合物/MAO体系催化乙烯齐聚 被引量:10
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作者 曹晨刚 姜涛 +3 位作者 闫卫东 刘彬彬 刘盘阁 胡友良 《石油化工》 CAS CSCD 北大核心 2003年第1期24-27,共4页
合成了2种双亚胺基吡啶铁系催化剂,以甲苯为溶剂,甲基铝氧烷(MAO)为助催化剂,催化乙烯齐聚合成线性α-烯烃。催化剂表现出超高的活性和对线性α-烯烃良好的选择性。同时考察了反应温度、乙烯压力、n(Al)/n(Fe)及对位取代基团等因素对催... 合成了2种双亚胺基吡啶铁系催化剂,以甲苯为溶剂,甲基铝氧烷(MAO)为助催化剂,催化乙烯齐聚合成线性α-烯烃。催化剂表现出超高的活性和对线性α-烯烃良好的选择性。同时考察了反应温度、乙烯压力、n(Al)/n(Fe)及对位取代基团等因素对催化活性和齐聚产物组成的影响。 展开更多
关键词 铁系双亚胺基吡啶配合物 mao体系 催化 乙烯 齐聚 铁系催化剂 Α-烯烃
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新型铁配合物/MAO催化乙烯低聚 被引量:6
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作者 宁英男 刘晓瑜 +2 位作者 王力搏 黄志军 姜涛 《化工进展》 EI CAS CSCD 北大核心 2006年第6期680-683,共4页
设计并合成了一种新型的单亚胺基吡啶铁配合物,与助催化剂甲基铝氧烷(MAO)组成催化体系用于乙烯低聚制备线性α-烯烃,考察了反应温度、反应压力、n(Al)/n(Fe)、主催化剂浓度及反应时间等因素对催化活性和低聚产物组成的影响。结果表明:... 设计并合成了一种新型的单亚胺基吡啶铁配合物,与助催化剂甲基铝氧烷(MAO)组成催化体系用于乙烯低聚制备线性α-烯烃,考察了反应温度、反应压力、n(Al)/n(Fe)、主催化剂浓度及反应时间等因素对催化活性和低聚产物组成的影响。结果表明:新型的铁配合物/MAO催化体系用于乙烯低聚,具有活性高和低碳数线性α–烯烃选择性高等特点。 展开更多
关键词 铁配合物 乙烯低聚 线性Α-烯烃 甲基铝氧烷(mao)
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低温下多级AO-MBR工艺处理市政污水中试研究 被引量:22
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作者 张晓飞 戴海平 +2 位作者 孙磊 张程 吴云 《水处理技术》 CAS CSCD 北大核心 2017年第3期73-77,共5页
针对低温条件下常规水处理技术难以满足出水要求的问题,对多级AO-膜生物反应器(MAO-MBR)工艺处理市政污水的情况进行研究,考察在低温下(7~13℃)对有机物和氮磷的去除效果。结果表明,在DO的质量浓度2.0 mg/L、回流体积比150%、HRT为18 h... 针对低温条件下常规水处理技术难以满足出水要求的问题,对多级AO-膜生物反应器(MAO-MBR)工艺处理市政污水的情况进行研究,考察在低温下(7~13℃)对有机物和氮磷的去除效果。结果表明,在DO的质量浓度2.0 mg/L、回流体积比150%、HRT为18 h、MLSS的质量浓度6 g/L条件下,NH_3-N负荷、TN负荷分别为15 g/(kg·m^3)、20 g/(kg·m^3),出水COD、NH_3-N、TN、TP的去除率可分别达到96%、98%、85%、97.5%,出水水质达到GB 18918-2002的一级A标准。 展开更多
关键词 mao-MBR工艺 市政污水 低温 一级A标准
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西柏坡时期毛泽东民心思想与中国革命的历史进程
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作者 姚志军 姚雷 《河北师范大学学报(哲学社会科学版)》 2024年第5期1-10,共10页
西柏坡这一段历史时期,是第四次人民大革命的高潮期。作为这场人民大革命浪潮的领航人,毛泽东科学运用马克思主义基本原理,准确把握民心动向,深刻洞察民心规律,不断引导和推动“民心向我”转化,以丰富的民心思想、正确的方针政策和举措... 西柏坡这一段历史时期,是第四次人民大革命的高潮期。作为这场人民大革命浪潮的领航人,毛泽东科学运用马克思主义基本原理,准确把握民心动向,深刻洞察民心规律,不断引导和推动“民心向我”转化,以丰富的民心思想、正确的方针政策和举措,凝聚起亿万中国人民的磅礴伟力,推动中国革命和中国历史实现重大转折。毛泽东民心思想的基本内容包括分析民心动向、揭示民心向背规律、引领民心方略;历史作用表现为把握历史大势、制定施行正确的政策和策略、推动中国革命的历史进程;主要特征包含鲜明的阶级性、人民性、国际性、辩证性、动态性、实践性。深入研究探讨西柏坡时期毛泽东民心思想与中国革命历史进程的内在逻辑关系,无疑具有重要的历史意义和现实意义。 展开更多
关键词 西柏坡时期 毛泽东 民心思想 人民大革命 历史进程
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