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你离“好新闻”并不远——透过几篇获奖作品谈关于新闻写作的几点启发
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作者 祁洁 《采写编》 2022年第12期140-142,共3页
什么样的稿件属于好新闻?如何写出优秀、有冲击力的新闻作品?平日工作中,许多新闻记者都常常为此苦恼。能否写出好的新闻作品,不仅关系到职称的评定,更重要的是关系到记者新闻敏感性的培养和写作水平的提高。在当前媒体融合的大背景下,... 什么样的稿件属于好新闻?如何写出优秀、有冲击力的新闻作品?平日工作中,许多新闻记者都常常为此苦恼。能否写出好的新闻作品,不仅关系到职称的评定,更重要的是关系到记者新闻敏感性的培养和写作水平的提高。在当前媒体融合的大背景下,记者应如何练好“内功”,才能写出有深度、有影响力的新闻稿件?文章以笔者近几年写过的几篇获奖新闻作品为例,对稿件的选题、写作角度及写作方法等一一进行深入剖析,旨在为同行提供借鉴。 展开更多
关键词 “天空” “接地气” “过筛子” “挖矿” “顺藤摸瓜”
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Synthesis of FER zeolite with piperidine as structure-directing agent and its catalytic application 被引量:4
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作者 Weifeng Chu Fucun Chen +7 位作者 Ce Guo Xiujie Li Xiangxue Zhu Yang Gao Sujuan Xie Shenglin Liu Nan Jiang Longya Xu 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第11期1880-1887,共8页
The synthesis of ferrierite(FER)zeolite using piperidine as an organic structure‐directing agent was investigated.X‐ray diffraction,X‐ray fluorescence,N2‐adsorption,and scanning electron microscopy were used to ch... The synthesis of ferrierite(FER)zeolite using piperidine as an organic structure‐directing agent was investigated.X‐ray diffraction,X‐ray fluorescence,N2‐adsorption,and scanning electron microscopy were used to characterize the crystal phases,textural properties,and particle morphologies of the zeolite samples.The crystallization behavior of the FER zeolite was found to be directly related to crystallization temperature.At150?C,pure FER phase was observed throughout crystallization.At160–170?C,MWW phase appeared first and gradually transformed into FER phase over time,indicating that the FER phase was thermodynamically favored.In the piperidine‐Na2O‐H2O synthetic system,alkalinity proved to be the crucial factor determining the size and textural properties of FER zeolite.Furthermore,the obtained FER samples exhibited good catalytic performance in the skeletal isomerization of1‐butene. 展开更多
关键词 FER zeolite PIPERIDINE Crystallization process MWW zeolite Skeletal isomerization
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A Frequency-Response Study on Sorption of Thiophene and Benzene on NiY Zeolite 被引量:4
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作者 Lai Junling1,2 Song Lijuan1,2 +1 位作者 Sun Zhaolin1,2(1.Colledge of Chemistry & Chemical Engineering,China University of Petroleum(East China),Dongying 257061 2.Liaoning Key Laboratory of Petrochemical Engineering,Liaoning Shihua University) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2011年第2期24-28,共5页
The adsorption behavior of thiophene and benzene on NiY zeolite has been investigated by the frequency response(FR) method.The FR spectra of thiophene and benzene on NiY zeolite were recorded at 302-335 K in a pressur... The adsorption behavior of thiophene and benzene on NiY zeolite has been investigated by the frequency response(FR) method.The FR spectra of thiophene and benzene on NiY zeolite were recorded at 302-335 K in a pressure range of 26.6-266 Pa.The results showed that adsorption was found to be the rate-controlling process for the thiophene/NiY zeolite system,and there were two different adsorption processes.Two kinds of adsorption models have been proposed,namely:the S-M interaction(low frequency adsorption) and the π-complexation(high frequency adsorption).High frequency adsorption obeyed the Langmuir model.By combining the FR method and Langmuir model,the adsorption site of high frequency adsorption process at 302 K and 335 K was 3.172 mmol/g and 2.974 mmol/g,respectively,and on the combined adsorption isotherms,the adsorption site of the low frequency adsorption process at 302 K and 335 K was 0.308 mmol/gand 0.436 mmol/g,respectively.The low frequency adsorption process(S-M interaction) was the main adsorption process.The diffusion process was the rate-controlling process for the benzene-NiY zeolite system. 展开更多
关键词 frequency response THIOPHENE BENZENE NiY zeolite adsorption site
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A study of particles penetration in sieving process on a linear vibration screen 被引量:18
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作者 Zhanfu Li Xin Tong 《International Journal of Coal Science & Technology》 EI 2015年第4期299-305,共7页
This paper presented an investigation of particle collision and penetration using the discrete element method to understand the motion of particles and improve theoretical treatment in the sieving process. The process... This paper presented an investigation of particle collision and penetration using the discrete element method to understand the motion of particles and improve theoretical treatment in the sieving process. The process progressively was divided into looseness, stratification, collision, and penetration. Particle penetration has a direct effect on the screening performance. The penetration probability was defined, and the mathematical relationships between particle penetration and vibration parameters were established using the least squares method. To obtain the ideal penetration probability for materials the amplitude and frequency should preferably be near 3.0 mm and 25 Hz, respectively. The vibration direction angle has only a slight effect on penetration. The stage of the screening process from 0.1 to 0.7 s is the primary region for collision and penetration. This paper focused on the sieving process to more fully understand how particle collision and penetration influence the screening efficiency. 展开更多
关键词 Penetration probability COLLISION Discrete element method Sieving process
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Investigation of the Ion-Exchange Behavior of Zeolite Y in the Presence of Resin 被引量:2
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作者 Zhang Yi Zheng Jinyu +3 位作者 Liu Zhongqing Gao Xiuzhi Luo Yibin Zong Baoning 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第2期50-56,共7页
Ion-exchange process of zeolite Y using ammonium-type resin as an exchange reagent was successfully carried out. The effect of temperature, space velocity and ion concentration on the breakthrough curves was carefully... Ion-exchange process of zeolite Y using ammonium-type resin as an exchange reagent was successfully carried out. The effect of temperature, space velocity and ion concentration on the breakthrough curves was carefully investigated. At the first exchange section, the maximum proportion of qualified zeolites(QR) was obtained at a temperature of 70 ℃, a weight hourly space velocity of 0.61 h-1, and an ion concentration of 197 mg/L. The minimum length of mass-transfer zone(MTZ) of the resin bed was achieved at a temperature of 70 ℃, a space velocity of 0.61 h-1, and an ion concentration of 423 mg/L. At the second exchange section, the length of MTZ of the resin bed was significantly increased, and the exchange of Na+ ions contained in zeolite Y was more difficult than that achieved at the first exchange section. In both the first and the second exchange sections, the zeolite Y subjected to ion exchange with the resin maintained the similar physical and chemical properties as compared to those exchanged by the conventional approaches, but the zeolite Y, which was obtained after ion exchange, contained a significantly lower content of Na2 O. 展开更多
关键词 zeolite Y RESIN ion-exchange
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Study on Crystallization of Titanium Silicalite Zeolite (Ⅱ)
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作者 Lin Min Zhu Bin +1 位作者 Shu Xingtian Wang Xieqing (Research Institute of Petroleum Processing, Beijing 100083) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2009年第1期31-38,共8页
In order to investigate the rules on formation of zeolite during crystallization of titanium silicalite zeolite (TS-1) the X-ray diffractometry and Foulier transform infra-red spectrometry were applied to track the pr... In order to investigate the rules on formation of zeolite during crystallization of titanium silicalite zeolite (TS-1) the X-ray diffractometry and Foulier transform infra-red spectrometry were applied to track the process of crystallization of titanium silicalite zeolite. The research results revealed that at the initial stage of crystallization the interactions between silica gel and titania gel in the polymer blend could gradually lead to the formation of tiny crystal nuclei with complicated structure that could slowly grow up to form molecular sieves. Quite different from the conventional zeolites that use the acid sites as the catalytically active centers, the oxidative reactivity of the titanium silicalite zeolite was not proportional to its crystallinity and is associated with the oxidative centers of titanium contained in the zeolite. 展开更多
关键词 titanium silicalite zeolite TS- 1 hollow titanium silicalite HTS CRYSTALLIZATION CHARACTERIZATION
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Study on Oxidative Desulfurization Performance of Mesoporous Alumina Material
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作者 Xu Li 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2009年第2期49-51,共3页
This article refers to the study on the performance of mesoporous silica used as the catalyst for oxidative desulfurization reactions. The test results revealed that under mild reaction conditions using tert-butyl hyd... This article refers to the study on the performance of mesoporous silica used as the catalyst for oxidative desulfurization reactions. The test results revealed that under mild reaction conditions using tert-butyl hydroperoxide as the oxidizing agent the content of dibenzothiophene(DBT) contained in oil samples could be reduced from 5000 ppm to less than 5 ppm. Furthermore,the mesoporous silica material can be easily regenerated and recycled. 展开更多
关键词 clean energy catalytic oxidative desulfurization mesoporous silica
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SUPERSATURATED DESIGN WITH MORE THAN TWO LEVELS 被引量:6
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作者 LU XUAN SUN YIZHOU Department of Mathematical Science, Tsinghua University, Beijing 100084, China. 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2001年第2期183-194,共12页
Supersaturated designs are useful in screening experiments. This paper discusses the topic of multi-level supersaturated design. Two quantities, E(d2) and Df, are proposed to evaluate the optimality of supersaturated ... Supersaturated designs are useful in screening experiments. This paper discusses the topic of multi-level supersaturated design. Two quantities, E(d2) and Df, are proposed to evaluate the optimality of supersaturated designs. A lower bound of E(d2) is obtained with a necessary condition for achieving it. Some E(d2)-optimal supersaturated designs of 3, 4, and 5 levels are given. 展开更多
关键词 D-EFFICIENCY Screening experiment Fractional factorial design ORTHOGONALITY
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