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晶种和有机模板剂接力导向合成ZSM-5分子筛及其催化性能

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石油炼制与化工 2024年第7期55卷 62-68页

作者：张燕挺任嘉欣郭云鸦李晓峰窦涛太原理工大学化学工程与技术学院太原030024

以晶种和有机模板剂接力导向(简称接力法)合成出ZSM-5分子筛,晶型、形貌、体相硅铝比和孔结构性质等均与传统法合成的ZSM-5分子筛接近。对比接力法和传统法制备的ZSM-5分子筛在以1,3,5-三异丙苯催化裂化为探针反应上的催化性能,结果是... 详细信息

以晶种和有机模板剂接力导向(简称接力法)合成出ZSM-5分子筛,晶型、形貌、体相硅铝比和孔结构性质等均与传统法合成的ZSM-5分子筛接近。对比接力法和传统法制备的ZSM-5分子筛在以1,3,5-三异丙苯催化裂化为探针反应上的催化性能,结果是接力法制备的ZSM-5分子筛上的1,3,5-三异丙苯转化率较低,表明此方法制备的ZSM-5分子筛表面富硅贫铝。进一步,将两种方法合成的分子筛制备成异构化催化剂,应用于催化乙苯脱乙基型二甲苯异构化反应,结果表明,相同反应条件下接力法制备的ZSM-5分子筛上的乙苯转化率更高,而异构化活性和二甲苯损失率更低。可见,晶种和有机模板剂接力导向是制备铝含量不同的核壳分子筛的一种可行方法。

关键词：分子筛乙苯脱乙基二甲苯异构化晶种有机模板剂

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危险废物灰渣玻璃化处理及资源化利用

化学工程 2024年第4期52卷 7-10,16页

作者：李小锋于伟锋张召锋孟祥琪王肖哲陕西建工安装集团有限公司陕西西安710068

危险废物焚烧、热解等过程产生的飞灰和底渣仍属于危险废物,其处理会占用大量土地。分析危险废物灰渣组分及熔融特性,设计相应的富氧燃烧熔融工艺、余热回收工艺及烟气净化工艺。根据固体废物玻璃化处理产物的判定、环境安全质量要求、... 详细信息

危险废物焚烧、热解等过程产生的飞灰和底渣仍属于危险废物,其处理会占用大量土地。分析危险废物灰渣组分及熔融特性,设计相应的富氧燃烧熔融工艺、余热回收工艺及烟气净化工艺。根据固体废物玻璃化处理产物的判定、环境安全质量要求、应用技术要求,确定熔融工艺玻璃化产物的资源化利用方向。可以得知:燃料式富氧燃烧熔融玻璃化处理工艺能够固化重金属并完全分解二噁英,解决危险废物填埋二次污染的问题;系统烟气余热可回收利用以降低系统能耗,熔融玻璃化处理产物可替代建筑材料资源化再利用。

关键词：固体危险废物液态排渣焚烧玻璃化处理废物再利用

大相对孔径激光测距接收光学系统及杂散光抑制

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激光与光电子学进展 2024年第5期61卷 496-504页

作者：周星宇孙亮潘俏吴绍龙曹国洋李孝峰苏州大学光电科学与工程学院江苏苏州215006 苏州大学苏州纳米科技协同创新中心江苏苏州215006 苏州大学教育部现代光学技术重点实验室江苏苏州215006 苏州大学江苏省先进光学制造技术重点实验室江苏苏州215006

为解决目前激光测距接收光学系统存在的难点,即系统在具有充足进光量的同时又要保证其低制造成本和轻小型化,基于拉格朗日不变量理论分析设计了一种大相对孔径接收光学系统。系统采用6片式伽利略型标准球面镜,使用光敏面直径为0.5 mm的... 详细信息

为解决目前激光测距接收光学系统存在的难点,即系统在具有充足进光量的同时又要保证其低制造成本和轻小型化,基于拉格朗日不变量理论分析设计了一种大相对孔径接收光学系统。系统采用6片式伽利略型标准球面镜,使用光敏面直径为0.5 mm的雪崩光电二极管(APD)探测回波光信号,优化后的系统入瞳直径为50 mm,相对孔径为1∶0.9,系统总长为114.9 mm,拉格朗日不变量为125 mrad·mm,获得了较为充足的进光量的同时满足低成本小型化要求。为降低杂散光的影响,进一步设计了遮光罩及镜筒栅栏结构。杂散光模拟追迹结果表明,系统在20°~85°离轴角视场外的杂散光抑制可以达到激光测距系统要求。在接收光学系统拉格朗日不变量为125 mrad·mm的前提下,激光测距系统的测距量程在加入光学系统后综合提升了21倍,表明该接收光学系统具有较大应用价值。

关键词：激光测距光学设计拉格朗日不变量大相对孔径杂散光分析

cGAS-STING信号通路:类风湿关节炎的潜在治疗靶点

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中华微生物学和免疫学杂志 2024年第5期44卷 460-467页

作者：苏蓉慧程丽云字晓宇王会李小峰王彩虹山西医科大学第二医院风湿免疫科太原030001

环磷酸鸟苷-腺苷酸合成酶-干扰素基因刺激因子(cyclic GMP-AMP synthase-stimulator of interferon gene,cGAS-STING)信号通路作为固有免疫系统的重要组成部分,是胞质DNA识别的主要途径,cGAS可由多种胞质双链DNA触发,成为连接自身免疫... 详细信息

环磷酸鸟苷-腺苷酸合成酶-干扰素基因刺激因子(cyclic GMP-AMP synthase-stimulator of interferon gene,cGAS-STING)信号通路作为固有免疫系统的重要组成部分,是胞质DNA识别的主要途径,cGAS可由多种胞质双链DNA触发,成为连接自身免疫、无菌炎症反应和细胞衰老的重要桥梁。近年来,cGAS-STING通路在自身免疫性疾病中越来越受到关注。在类风湿关节炎(rheumatoid arthritis,RA)中,中性粒细胞胞外陷阱(neutrophil extracellular traps,NETs)通过cGAS-STING通路引发Ⅰ型干扰素反应、加速抗瓜氨酸化蛋白抗体(anti-citrullinated peptide antibody,ACPA)产生;此外,cGAS-STING通路还通过促进成纤维细胞样滑膜细胞增殖活化、M1型巨噬细胞极化参与滑膜炎及骨破坏,参与RA的发生发展。抑制cGAS-STING通路或其下游信号通路可以减少RA的滑膜炎症,cGAS-STING通路可能是RA的潜在治疗靶点。

关键词： cGAS-STING信号通路类风湿关节炎 Ⅰ型干扰素胞质DNA感受器

ALGORITHM FOR ACOUSTIC PASSIVE LOCAliZATION WITH DUAL ARRAYS

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Chinese Journal of Mechanical Engineering 2008年第6期21卷 14-17页

作者： JIA Jingjing liU Mingjie li xiaofeng School of Aerospace Science and Engineering Beijing Institute of Technology Beijing 100081 China

Aiming at the problem of 3D target localization by time delay estimation, this paper proposes a new acoustic passive localization method, which can provide high precision localization estimation. The first step of the two-stage algorithm is to measure the azimuth angle and pitch angle at each single array, which can obtain high precision angle estimation but low precision range estimation. And in the second step, the location of acoustic source is calculated from the angles measured above and geometry position of the two arrays. Then the accuracy of localization estimation is discussed in theory, and the influence factors and localization error are analyzed by simulation. The simulation results validate the performance of the proposed algorithm, and show the precision of localization estimation with dual arrays is superior to single array.

关键词： Acoustic passive localization Dual arrays Target tracking

Application of coupled analysis methods for prediction of blast-induced dominant vibration frequency

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Earthquake Engineering and Engineering Vibration 2016年第1期15卷 153-162页

作者： li Haibo li xiaofeng li Jianchun Xia Xiang Wang Xiaowei State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China China Nuclear Power Engineering Company Ltd. Shenzhen 518031 China

Blast-induced dominant vibration frequency （DVF） involves a complex, nonlinear and small sample system considering rock properties, blasting parameters and topography. In this study, a combination of grey relational analysis and dimensional analysis procedures for prediction of dominant vibration frequency are presented. Six factors are selected from extensive effect factor sequences based on grey relational analysis, and then a novel blast-induced dominant vibration frequency prediction is obtained by dimensional analysis. In addition, the prediction is simplified by sensitivity analysis with 195 experimental blast records. Validation is carried out for the proposed formula based on the site test database of the first- period blasting excavation in the Guangdong Lufeng Nuclear Power Plant （GLNPP）. The results show the proposed approach has a higher fitting degree and smaller mean error when compared with traditional predictions.

关键词： grey relational analysis dimensional analysis sensitivity analysis dominant vibration frequency prediction

Characteristics and generations of internal wave in the Sulu Sea inferred from optical satellite images

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Journal of Oceanology and limnology 2020年第5期38卷 1435-1444页

作者： ZHANG Xudong li xiaofeng ZHANG Tao CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences and Center for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China College of Geomatics Shandong University of Science and TechnologyQingdao 266071China

Characteristics and generation of internal waves(IWs)in the Sulu Sea are studied using Moderate-Resolution Imaging Spectroradiometer(MODIS)and Visible Infrared Imaging Radiometer Suite(VIIRS)images taken from October 2016 to September *** observations show that IWs in the Sulu Sea mainly located in the shallower western areas with occasional observations in the deeper eastern *** dominant length of wave crest(LWC)of IWs is between 50 and 150 km with the largest LWC reaching over 300 *** analysis of temporal distributions of IWs shows that March has the most IWs and July has the *** analysis shows that the seasonal variation is mainly due to the cloud contamination of optical satellite *** generation sites of IWs are analyzed using satellite *** possible generation sites for IWs in the western Sulu Sea and one generation site for IWs in the eastern Sulu Sea are found using the ray-tracing *** IW sources in the same strait are found,which may be due to the seawater fl ow over the strait in diff erent *** analysis shows that IWs with long wave crest in the Sulu Sea is a combined eff ort of all straits between small islands in the Sulu *** generated IWs with long wave crest in the eastern Sulu Sea are studied,which are generated at the straits around(121.5°E,6°N)by the nonlinear evolution of internal tide originated from the Sulu Archipelago.

关键词： internal waves(IWs) Sulu Sea Moderate-Resolution Imaging Spectroradiometer(MODIS) Suomi National Polar-Orbiting Partnership(NPP)

Particle Swarm Optimization-Support Vector Machine Model for Machinery Fault Diagnoses in High-Voltage Circuit Breakers

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中国机械工程学报：英文版 2020年第1期33卷 104-113页

作者： xiaofeng li Shijing Wu Xiaoyong li Hao Yuan Deng Zhao School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China

According to statistic data,machinery faults contribute to largest proportion of High-voltage circuit breaker failures,and traditional maintenance methods exist some disadvantages for that ***,based on the wavelet packet decomposition approach and support vector machines,a new diagnosis model is proposed for such fault diagnoses in this *** vibration eigenvalue extraction is analyzed through wavelet packet decomposition,and a four-layer support vector machine is constituted as a fault *** Gaussian radial basis function is employed as the kernel function for the *** penalty parameter c and kernel parameterδof the support vector machine are vital for the diagnostic accuracy,and these parameters must be carefully ***,a particle swarm optimizationsupport vector machine model is developed in which the optimal parameters c andδfor the support vector machine in each layer are determined by the particle swarm *** validity of this fault diagnosis model is determined with a real dataset from the operation ***,comparative investigations of fault diagnosis experiments with a normal support vector machine and a particle swarm optimization back-propagation neural network are also *** results indicate that the proposed fault diagnosis model yields better accuracy and e-ciency than these other models.

关键词： High-voltage circuit breaker Machinery fault diagnosis Wavelet packet decomposition Support vector machine

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基于实际地铁线路的全生命周期碳排放研究

都市快轨交通 2024年第1期37卷 82-87页

作者：李晓锋王荔栾承志于秋燕解建华罗丞朝清华大学建筑学院北京100084 北京市市政工程设计研究总院有限公司北京100084

在双碳战略的重大战略部署下,对轨道交通全生命周期碳排放进行研究,合理量化其碳排放水平是实现交通部门碳达峰、碳中和的重要措施。本文基于北京某新建地铁线路,对轨道交通全生命周期碳排放进行分析,建立了轨道交通全线、全生命周期的... 详细信息

在双碳战略的重大战略部署下,对轨道交通全生命周期碳排放进行研究,合理量化其碳排放水平是实现交通部门碳达峰、碳中和的重要措施。本文基于北京某新建地铁线路,对轨道交通全生命周期碳排放进行分析,建立了轨道交通全线、全生命周期的碳排放计算模型,并定量计算新建地铁线路全线、全生命周期的碳排放量。同时,对建设阶段和运营阶段的降碳措施做出分析,定量评估其降碳潜力。对全长81 km新建地铁线路进行碳排放量计算,得到建设阶段碳排放量为257万t CO_(2)eq,运营阶段为5.35万t CO_(2)eq/a,50年运营周期总计碳排放量524万t CO_(2)eq。建设阶段使用可再生材料及预制结构可减少碳排放量7%;运营阶段综合采用多种节能降碳措施后,可降碳27%;50年运营周期降碳潜力总计17%。该模型的建立对城轨交通全生命周期碳排放定量计算有指导意义,降碳措施的研究成果以期为城轨交通完成绿色低碳转型、实现交通部门碳达峰、碳中和提供参考。

关键词：城市轨道交通生命周期分析碳排放绿色低碳