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复配絮凝剂对细粒煤泥沉降的影响研究

煤炭加工与综合利用 2024年第4期 26-30,36页

作者：师露坡苏庆军中煤第九十二工程有限公司河北邯郸056000

以细粒难沉降煤泥为研究对象,以上清液浊度、初始沉降速度及煤泥水综合评价指标作为评定依据,研究了不同离子类型聚丙烯酰胺(PAM)单一及组合使用时对煤泥水沉降的影响。结果表明,絮凝剂单独使用时,非离子型PAM对煤泥水絮凝效果最好,在... 详细信息

以细粒难沉降煤泥为研究对象,以上清液浊度、初始沉降速度及煤泥水综合评价指标作为评定依据,研究了不同离子类型聚丙烯酰胺(PAM)单一及组合使用时对煤泥水沉降的影响。结果表明,絮凝剂单独使用时,非离子型PAM对煤泥水絮凝效果最好,在絮凝剂用量为180 g/t时,综合评价指标最高,为7.86 mm/(s·NTU),煤泥水上清液浊度为246.3 NTU。以2∶1比例对分子量为1000万和1400万的非离子型PAM进行复配,使用复配絮凝剂时煤泥水沉降效果进一步提高,当复配絮凝剂用量为180 g/t时,煤泥水沉降综合评价指标最高,达到27.86 mm/(s·NTU),同时絮团的分形维数增加,表明絮团的结构更加紧密,有利于提高煤泥水沉降效果。

关键词：选煤厂煤泥水沉降复配絮凝剂分形维数

Dynamic analysis of agricultural green development efficiency in China: Spatiotemporal evolution and influencing factors

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Journal of Arid Land 2023年第2期15卷 127-144页

作者： LIU Yiping lu chengpeng chen Xingpeng Institute of County Economic Development&Rural Revitalization Strategy Lanzhou UniversityLanzhou 730000China College of Earth and Environmental Science Lanzhou UniversityLanzhou 730000China

Green development of agriculture is important for achieving coordinated and high-quality regional development for China. Using provincial data from 1990 to 2020, this work explored the dynamics of agricultural green development efficiency of 31 provinces in China, its spatiotemporal characteristics, and its driving factors using a super-efficiency slacks-based measure(Super-SBM), the Malmquist productivity index(MPI), spatial autocorrelation, and a geographic detector. Results showed that the overall agricultural green development efficiency showed a U-shaped trend, suggesting a low level of efficiency. Although a gradient difference was visible among eastern, central, and western regions, the efficiency gap narrowed each year. Technological progress and efficiency both promoted agricultural green development efficiency, especially technological progress. Agricultural green development efficiency had significant spatial aggregation characteristics, but Moran’s Ⅰ result showed a downward trend from 2015 to 2020, indicating a risk of spatial dispersion in the later stage. The provinces with high agricultural green development efficiency were mainly concentrated in the eastern region, while those with low efficiency were concentrated in the central and western regions. Agricultural green development efficiency was influenced by various factors, which showed differences according to time and region. The impact of the labor force’s education level and technological progress increased during the study period, and significantly facilitated agricultural green development efficiency in the eastern region, while the central and western regions were still affected by the scale level and environmental regulation, reflecting the advantages of the eastern region in terms of economy and technology. In the future, strengthening agricultural scientific and technological innovation and deepening interprovincial cooperation can help further improve the level of green agricultural deve

关键词： regional development economy technology spatial evolution influencing factors super-efficiency slacks-based measure

清江流域亚硝胺及其前体物质的分布特征及风险评价

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环境科学 2024年第7期45卷 3930-3940页

作者：李梦轩陈英杰陈文文黄焕芳丁洋邢新丽陆燕勤祁士华中国地质大学(武汉)生物地质与环境地质国家重点实验室武汉430074 中国地质大学(武汉)环境学院武汉430074 桂林理工大学环境科学与工程学院桂林541006 生态环境部华南环境科学研究所国家环境保护水环境模拟与污染控制重点实验室广州510535 四川师范大学西南土地资源评价与监测教育部重点实验室成都610066

亚硝胺是一类具有高致癌性和致突变性的含氮有机污染物.支流水系作为我国中小城镇的主要饮用水源,其亚硝胺的污染情况尚不明确,关于支流河水中亚硝胺及其前体物质浓度的研究仍十分缺乏.以水体中常见8种亚硝胺为研究对象,检测了长江一级... 详细信息

亚硝胺是一类具有高致癌性和致突变性的含氮有机污染物.支流水系作为我国中小城镇的主要饮用水源,其亚硝胺的污染情况尚不明确,关于支流河水中亚硝胺及其前体物质浓度的研究仍十分缺乏.以水体中常见8种亚硝胺为研究对象,检测了长江一级支流清江河水及氯胺化处理后水样中亚硝胺浓度组成特征,并针对重要的污水排放源进行重点监测,分析亚硝胺及其前体物质的环境影响因素,评估其健康和生态风险.结果表明,清江河水共检出6种亚硝胺,其中主要亚硝胺为NDMA[(10±15)ng·L^(-1)]、NDEA[(9.3±9.3)ng·L^(-1)]和NDBA[(14±7.8)ng·L^(-1)],氯胺化反应后的水样中有7种亚硝胺检出,主要为NDMA-FP[(46±21)ng·L^(-1)]、NDEA-FP[(26±8.3)ng·L^(-1)]和NDBA-FP[(22±13)ng·L^(-1)];河水中亚硝胺的浓度分布整体呈现为中游高于上游和下游,在有污水排放与支流汇入点的亚硝胺浓度明显高于其他点位;对污水直接排放点的监测发现,携带有亚硝胺及其前体物质的污水输入是河水中亚硝胺的主要来源;此外,3种主控污染物NDMA、NDBA和NDEA的浓度存在一定相关性,主要原因是其存在相似的污水来源;饮用水源地亚硝胺浓度对当地居民存在潜在致癌风险(2.4×10^(-5));此外,由于清江具有较高的亚硝胺生成潜能,其饮用水致癌风险可能会更高;生态风险评价表明,亚硝胺对于清江流域的生态风险商值低于0.002,生态风险可忽略不计.

关键词：清江流域亚硝胺生成势(FP) 致癌风险生态风险

中强地震发震构造标志浅析——以2023年积石山M_(S)6.2地震为例

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地震 2024年第1期44卷 226-234页

作者：张军龙徐岳仁李文巧陈峰中国地震局地震预测研究所北京100036

地震地表破裂是地震发生的重要特征,是研究地震动力学、构造变形的重要手段。一般认为,M6 3/4以上的地震才会形成地表破裂。但近年来,也有M6.0左右的地震发生了地表破裂。本文旨在探讨中强地震地表破裂的识别方法。中强地震发震构造的... 详细信息

地震地表破裂是地震发生的重要特征,是研究地震动力学、构造变形的重要手段。一般认为,M6 3/4以上的地震才会形成地表破裂。但近年来,也有M6.0左右的地震发生了地表破裂。本文旨在探讨中强地震地表破裂的识别方法。中强地震发震构造的识别具有一定的挑战性,主要表现在以下几个方面:(1)中强地震地表破裂的规模(位错量、宽度、长度和深度)较小,容易被黄土层厚覆盖,掩盖地表破裂的痕迹,不易识别;(2)非构造成因裂缝干扰,使得难以区分构造成因地表破裂。本文以2023年积石山M_(S)6.2地震为例,对中强地震构造成因破裂的识别标志进行了初步分析,提出了以下识别标志:(1)地表破裂几何展布和剖面形态,地震伴生的次生灾害(滑坡、崩塌、砂土液化等)的线性分布为识别发震构造提供参考和线索;(2)地表破裂沿破裂走向呈现稳定地穿越不同地貌单元,至少穿越一条沟谷等低凹地貌;(3)地表破裂在地质剖面上表现出稳定的产状;(4)地表破裂伴生构造形态,地表沿破裂发育雁列式褶皱(挤压鼓包)与张裂缝交替出现的现象。本文提出的识别标志为中强地震发震构造的识别提供了新的思路。

关键词：青藏高原拉脊山断裂带 2023年积石山M_(S)6.2地震发震构造地震地表破裂

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响应曲面法优化废旧三元锂电池黑粉酸浸工艺

应用化工 2024年第5期53卷 1081-1085,1092页

作者：权朝明王敏彭正军逯启昌中国科学院青海盐湖研究所、中国科学院盐湖资源综合高效利用重点实验室青海西宁810008 青海省盐湖资源化学重点实验室青海西宁810008

使用盐酸直接浸出废旧三元锂电池黑粉中的锂、镍、钴、锰,采用基于Box-Behnken设计的响应曲面法,考察反应温度、酸浓度、时间对4种元素浸出率的影响。结果表明,直接酸浸法最佳工艺条件为:酸浓度6 mol/L,固液比250 g/L,反应温度60℃,反... 详细信息

使用盐酸直接浸出废旧三元锂电池黑粉中的锂、镍、钴、锰,采用基于Box-Behnken设计的响应曲面法,考察反应温度、酸浓度、时间对4种元素浸出率的影响。结果表明,直接酸浸法最佳工艺条件为:酸浓度6 mol/L,固液比250 g/L,反应温度60℃,反应时间7 h,2次浸出后,锂浸出率为99.96%,镍浸出率为99.73%,钴浸出率99.90%,锰含量为99.82%。

关键词：废旧三元锂电池酸浸响应曲面法

A comparative DFT+U study of CO oxidation on Pd-and Zr-doped ceria

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Journal of Rare Earths 2023年第7期41卷 1042-1048,I0003页

作者： lu chen Xinping Wu Xueqing Gong Key Laboratory for Advanced Materials and Joint International Research Laboratory for Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistryCentre for Computational Chemistry and Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Metal-doped ceria catalysts have been applied in many important catalytic *** this work,we performed density functional theory calculations corrected by on-site Coulomb interactions to study the Pd-and Zr-doped CeO_(2)(111) surfaces with the dopant at different *** formation of oxygen vacancies and CO oxidation were systematically calculated on the various doped *** find that both Pd and Zr doping can activate the surface lattice O and reduce the energy barriers of CO ***,the promotion effect of the Zr dopant is limited to its existence in the first surface layer,while for the Pd dopant,the surface activity can be greatly enhanced even it occurs far below the ***,CO_(2) can be generated directly on the Pd-doped surfaces through reaction between CO and surface O,while the surface intermediate CO_(2)^(δ-) may readily form and restrict the releasing of CO_(2) by further oxidation to carbonates on the Zr-doped *** analyses show that the doped Pd exists as Pd^(4+) and it has stronger electron affinity than other surface species during CO oxidation,contributing to the easy Pd^(4+) to Pd^(2+) transformation accompanied by direct CO_(2) formation at Pd-doped ceria.

关键词： CeO_(2) Metal doping CO oxidation Carbonate DFT+U Rare earths

Perception and Recognition of Vocalization in Anuran Mate Choice

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Asian Herpetological Research 2020年第4期11卷 394-400页

作者： Fang lu Yezhong TANG Qin chen Department of Ophthalmology West China HospitalSichuan UniversityChengdu 610041SichuanChina chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041SichuanChina

Vocal communications in frogs and toads have been highly diversified and become a hot topic in the fields of herpetology,ecology,and behavioral *** present short review summarized several interesting phenomena of vocal communication found mainly in anurans that might contribute to the individual identification of mates or rivals,including call matching,aggressive signaling,acoustic complexity,signal exaggeration,the first note effect and left hemisphere *** on the perception and recognition of vocal communications will facilitate our comprehension of the adaptive mechanisms and evolutionary paths of anuran signaling *** proposed here that comparative studies on acoustic signal structures,codes of sender status,and auditory neural responses based on phylogenetic relationships across species can highlight further the evolutionary trajectory in anurans.

关键词： anuran adaptive mechanism evolution phonotaxis vocal communication

市域(郊)铁路交流25kV供电制式对计轴的影响及抗干扰分析

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铁路通信信号工程技术 2024年第9期21卷 79-84页

作者：刘军梁东泽卢佳周乾宁波市市域铁路投资发展有限公司浙江宁波315000 北京全路通信信号研究设计院集团有限公司北京100070

市域(郊)铁路采用交流25 kV供电制式替代直流750 V/1500 V可以满足其高输送能力、高速度、低损耗的建设需求,但供电制式的改变,会对计轴等信号系统轨旁设备产生电磁干扰。结合25 kV供电制式干扰源以及主流计轴工作原理,分析如何从计轴... 详细信息

市域(郊)铁路采用交流25 kV供电制式替代直流750 V/1500 V可以满足其高输送能力、高速度、低损耗的建设需求,但供电制式的改变,会对计轴等信号系统轨旁设备产生电磁干扰。结合25 kV供电制式干扰源以及主流计轴工作原理,分析如何从计轴设备本身及外部措施规避计轴受扰情况。

关键词：市域(郊)轨道交通交流25 kV供电制式计轴

Fault Location Detection of Transmission Lines in Noise Environments Based on Random Matrix Theory

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 1233-1241页

作者： jun An Zihan Deng Haipeng chen Gang Mu Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology Ministry of Education(Northeast Electric Power University)Jilin 132012.Jilin ProvinceChina

Fault detection and location are critically significant applications of a supervisory control system in a smart *** methods,based on random matrix theory(RMT),have been practiced using measurements to detect short circuit faults occurring on transmission ***,the diagnostic accuracy is infuenced by the noise signal in the *** relationship between mean eigenvalue of a random matrix and noise is detected in this paper,and the defects of the Mean Spectral Radius(MSR),as an indicator to detect faults,are theoretically determined,along with a novel indicator of the shifting degree of maximum eigenvalue and its *** comparing the indicator and the threshold,the occurrence of a fault can be ***,an augmented matrix is constructed to locate the fault *** proposed method can effectively achieve fault detection via the RMT without any influence of noise,and also does not depend on system *** experiment results are based on the IEEE 39-bus ***,actual provincial grid data is applied to validate the effectiveness of the proposed method.

关键词： Fault detection maximum eigenvalue noise random matrix theory smart grid