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Regulating crystal phase of TiO_(2) to enhance catalytic activity of Ni/TiO_(2) for solar-driven dry reforming of methane

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燃料化学学报（中英文） 2024年第9期52卷 1203-1213页

作者： HE Zhanjun GONG Kun DAI Yuanyuan NIU Qiang lin tiejun ZHONG Liangshu Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China National Enterprise Technology Center Inner Mongolia Erdos Electric Power and Metallurgy Group Co.LtdOrdos 016064China

Ni/TiO_(2) catalyst is widely employed for photo-driven DRM reaction while the influence of crystal structure of TiO_(2) remains *** this work,the rutile/anatase ratio in supports was successfully controlled by varying the calcination temperature of anatase-TiO_(2).Structural characterizations revealed that a distinct TiO_(x) coating on the Ni nanoparticles(NPs)was evident for Ni/TiO_(2)-700 catalyst due to strong metal-support *** is observed that the TiOx overlayer gradually disappeared as the ratio of rutile/anatase increased,thereby enhancing the exposure of Ni active *** exposed Ni sites enhanced visible light absorption and boosted the dissociation capability of CH4,which led to the much elevated catalytic activity for Ni/TiO_(2)-950 in which rutile ***,the catalytic activity of solar-driven DRM reaction was significantly influenced by the rutile/anatase ***/TiO_(2)-950,characterized by a predominant rutile phase,exhibited the highest DRM reactivity,with remarkable H_(2) and CO production rates reaching as high as 87.4 and 220.2 mmol/(g·h),*** rates were approximately 257 and 130 times higher,respectively,compared to those obtained on Ni/TiO_(2)-700 with *** study suggests that the optimization of crystal structure of TiO_(2) support can effectively enhance the performance of photothermal DRM reaction.

关键词： dry reforming of methane photothermal catalysis crystal phase TiO_(2) metal-support interaction

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超深井套管卡瓦效应的拉伸极限载荷理论计算

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西南石油大学学报（自然科学版） 2024年第2期46卷 155-163页

作者：练章华万智勇宋琳赵朝阳林铁军油气藏地质及开发工程全国重点实验室·西南石油大学四川成都610500 中国石油新疆油田分公司工程技术研究院新疆克拉玛依834000

针对新疆某油田超深井井口套管悬重过大,造成卡瓦牙对套管外壁齿入损伤,且累计损伤导致卡瓦悬挂器套管断裂失效的事故频繁,提出了“卡瓦效应的拉伸极限载荷”来评价井口卡瓦悬挂器夹持部分套管的强度设计,具体为基于第三强度理论和第四... 详细信息

针对新疆某油田超深井井口套管悬重过大,造成卡瓦牙对套管外壁齿入损伤,且累计损伤导致卡瓦悬挂器套管断裂失效的事故频繁,提出了“卡瓦效应的拉伸极限载荷”来评价井口卡瓦悬挂器夹持部分套管的强度设计,具体为基于第三强度理论和第四强度理论,分别建立了井口卡瓦悬挂器夹持套管的“卡瓦效应拉伸极限载荷”计算模型。计算结果表明,从安全角度评价套管强度,采用第三强度理论计算卡瓦悬挂器套管的卡瓦效应拉伸极限载荷更合理,但为更充分利用材料的力学性能,应采用第四强度理论进行评价,还得到在四通有限空间内,可以保证有较大的卡瓦效应拉伸极限载荷的最佳卡瓦半锥角为23°~25°,最佳卡瓦有效接触长度为135~145 mm。研究方法和结果将为卡瓦悬挂器井口套管的强度设计、各种安全施工作业等提供理论依据。

关键词：深井超深井卡瓦悬挂器套管断裂力学模型拉伸极限载荷

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Low-temperature synthesis of novel ZnO nanowire microspheres on silicon substrates

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Rare Metals 2007年第3期26卷 242-246页

作者： LI Xinyu GUO Jian DING Shulong lin tiejun DONG Jingtao College of Material and Photoelectricity Physics Xiangtan University Xiangtan 411105 China

Microspheres covered with ZnO nanowires were fabricated by oxidative evaporation of pure zinc powder without catalyst at 450℃. X-my diffraction （XRD） demonstrates that the as-obtained sample can be indexed to high crystaUinity with wurtzite structure. The structural features associated with different growth stages were monitored using scanning elec- tron microscope （SEM）, which described the direct observation nucleation and growth process. Meanwhile, room temperature photoluminescence （PL） spectrum showed a UV emission at -388 nm and a broad green emission at -505 nm. The ZnO nanowires with the self-catalyzed growth mechanism were discussed in detail.

关键词： self-catalyst ZnO nanowire microspheres photoluminescence nanowires

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稠油热采井射孔孔眼应力分析及影响因素

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特种油气藏 2024年第1期31卷 152-158页

作者：梁疆岭杨洪苏宏益林铁军赵朝阳但晗中国石油新疆油田分公司新疆克拉玛依834000 西南石油大学油气藏地质及开发工程全国重点实验室四川成都615000

针对稠油热采井生产过程中,射孔井段套管频繁出现损伤断裂的问题,基于弹塑性和热力学理论,采用有限元方法建立注汽—焖井—生产过程射孔套管有限元热力学耦合模型,对各阶段射孔套管应力分布特征进行研究,并开展不同射孔参数下射孔套管... 详细信息

针对稠油热采井生产过程中,射孔井段套管频繁出现损伤断裂的问题,基于弹塑性和热力学理论,采用有限元方法建立注汽—焖井—生产过程射孔套管有限元热力学耦合模型,对各阶段射孔套管应力分布特征进行研究,并开展不同射孔参数下射孔套管强度影响规律分析。研究表明:生产过程中射孔孔眼位置出现明显应力集中现象,在温差及内外压差等共同作用下,注采前期套管应力最大可达498.16 MPa,并逐渐产生塑性失效现象,当注采作业完成时,套管塑性失效现象最严重;随着射孔相位角增大,射孔密度对Mises应力值的影响逐渐减小,而套管孔眼最大应力与射孔相位角成反比关系。该研究对延长稠油热采井射孔套管使用年限和保障正常生产作业具有十分重要的意义。

关键词：稠油热采套管损伤射孔孔眼套管强度,应力集中

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Advances in direct production of value-added chemicals via syngas conversion

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Science China Chemistry 2017年第7期60卷 887-903页

作者： Yunlei An tiejun lin Fei Yu Yanzhang Yang Liangshu Zhong Minghong Wu Yuhan Sun School of Environmental and Chemical Engineering Shanghai UniversityShanghai 200444China CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201203China University of the Chinese Academy of Sciences Beijing 100049China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201203China

Syngas conversion to fuels and chemicals is one of the most challenging subjects in the field of C1 chemistry. It is considered as an attractive alternative non-petroleum-based production route. The direct synthesis of olefins and alcohols as high value-added chemicals from syngas has drawn particular attention due to its process simplicity, low energy consumption and clean utilization of carbon resource, which conforms to the principles of green carbon science. This review describes the recent advances for the direct production of lower olefins and higher alcohols via syngas conversion. Recent progress in the development of new catalyst systems for enhanced catalytic performance is highlighted. We also give recommendations regarding major challenges for further research in syngas conversion to various chemicals.

关键词： green carbon science syngas conversion Fischer-Tropsh Fischer-Tropsh to olefins higher alcohol synthesis

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Effect of Sodium on the Structure-Performance Relationship of Co/SiO2 for Fischer-Tropsch Synthesis

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Chinese Journal of Chemistry 2017年第6期35卷 918-926页

作者： Yuanyuan Dai Fei Yu Zhengjia Li Yunlei An tiejun lin Yanzhang Yang Liangshu Zhong Hui wang Yuhan Sun CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201203 China University of the Chinese Academy of Sciences Beijing 100049 China School of Chemistry and Molecular Engineering East China Normal University Shanghai 200062 China College of Environmental and Chemical Engineering Shanghai University Shanghai 200444 China School of Physical Science and Technolog.v Shanghai Tech University Shanghai 201203 China

A series of Co/SiO2 catalysts with different sodium （Na）loadings （0, 0.1, 0.2, 0.5 and I wt%） were prepared and evaluated for Fischer-Tropsch reaction to study the effect of Na on the catalyst structure and catalytic performance. The addition of Na was found to decrease the catalytic activity and hydrocarbon selectivity, but increase CO2 selec- tivity due to the enhanced WGS activity. The addition of Na also resulted in higher selectivity to oxygenates （alco- hols and aldehydes） and O/P ratio as well as the shift of hydrocarbons to lower carbon numbers. Structure charac- terization revealed a decrease in the surface area and particles size for the calcined samples with the addition of Na. CozC was formed during the reaction process for the Na-promoted catalysts. As a result, a new Co/Co2C bifunc- tional active sites were generated for oxygenates formation leading to increasing oxygenates selectivity. In addition, the Co2C nanoparticles alone may also act as dual active sites for oxygenate formation at high reaction pressure over the promoted catalysts with high Na loading.

关键词： Fischer-Tropsch synthesis structure-performance relationship sodium cobalt carbide oxygenates

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页岩油水平井上提下放过程中套管力学特征分析

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石油管材与仪器 2024年第3期10卷 33-38,I0004页

作者：赵朝阳林铁军朱泽林于浩练章华西南石油大学油气藏地质及开发工程国家重点实验室四川成都610500

为了提高页岩油水平井套管下入能力,上提下放技术已成为套管下放作业中必不可少的一环。然而,在多次上提下放过程中,井筒套管普遍出现断裂失效行为。以某口页岩油水平井实际套管下放作业为基础,结合弹塑性理论,采用有限元软件建立全井... 详细信息

为了提高页岩油水平井套管下入能力,上提下放技术已成为套管下放作业中必不可少的一环。然而,在多次上提下放过程中,井筒套管普遍出现断裂失效行为。以某口页岩油水平井实际套管下放作业为基础,结合弹塑性理论,采用有限元软件建立全井段套管上提下放动力学模型,分别对单次以及多次作业过程中井筒套管轴向力、摩阻以及Mises应力分布状态开展研究。研究发现:在上提下放过程中,套管累积弹性能在上提阶段得到一定释放,在下放阶段重新累积;单次上提下放作业后,井筒套管Mises应力、下放摩阻及轴向力相较作业前明显下降,套管的下入能力得到一定提升;短时间内多次上提下放过程中,随着局部位置套管的弹性能快速累积释放,部分位置套管在摩阻作用下始终处于累积状态,最终导致局部套管屈曲行为进一步加剧。开展套管上提下放过程中的力学行为研究以及风险分析,可为页岩油水平井套管高效安全下入提供指导。

关键词：页岩油水平井套管下放累积下放摩阻上提下放弹性能

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Study on the fluid flow rule of five-cylinder plunger pump hydraulic end

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Petroleum 2018年第4期4卷 457-465页

作者： Zhanghua Lian Yang Liu tiejun lin Li Li Zhongqing Lei Chuanjun Han State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University610500PR China Institute of Technology CNPC Xinjiang Oil Company834000PR China Engineering Technology Research Institute CNPC Bohai Drilling Engineering Company LimitedTianjin300280PR China

The change of velocity and pressure of flow field in suction and discharge chamber of five-cylinder plunger pump obtained by CFD under maximum and minimum stroke,the results show that:when the stroke is 79 rpm,the internal of pump head will produce pressure holding,and the internal organization of pump head body will be in a fatigue state of high pressure for a long *** the rotate angle is small,the peak velocity at the gap of valve disc and valve seat reaches 9.60m/s,which is the orifice jet *** the stroke is 299 rpm,the overall velocity curve is relatively stable,but the velocity of fluid flow through the pump head body is larger,and the maximum velocity reaches 18.72 m/s at the bottom corner of valve,it will produce the circumfluence and vortex discharge chamber at the same time,which will cause the increase of vibration of pump head *** it should use proper punching gear in order to conducive to overall working life of pump.

关键词： Five-cylinder plunger pump Pressure holding Orifice jet Vibration

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MIMO Capacity Bounds with Doubly Correlated Rician Channel in Geometrical Channel Model

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China Communications 2010年第5期7卷 9-13页

作者： Li Yonghua He Zhiqiang Lv tiejun lin Jiaru Key Laboratory of Universal Wireless Comunications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 P. R. China

MIMO system can provide higher capacity in independent conditions. When the spatial-temporal fading correlation exists, the capacity may decrease. In this paper, the geometrical MIMO channel model is presented with Rician factor. Based on the MIMO ergodic capacity, the capacity bounds are derived with arbitrary finite number of antennas. The bounds are derived in the exact expressions in doubly correlated MIMO R/clan channel. Then a simple expression for the capacity bounds is attained for the high SNR. Finally, the tightness of derived bounds is verified by Monte Carlo simulation.

关键词： MIMO Rician capacity bounds

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Robust Inference for Censored Quantile Regression

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Journal of Systems Science & Complexity 2024年

作者： TANG Yuanyuan WANG Xiaorui ZHU Jianming lin Hongmei TANG Yanlin TONG tiejun School of Statistics and Information Shanghai University of International Business and Economics Department of Statistics and Data Science Southern University of Science and Technology School of Statistics KLATASDS-MOE East China Normal University Department of Mathematics Hong Kong Baptist University

In various fields such as medical science and finance, it is not uncommon that the data are heavy-tailed and/or not fully observed, calling for robust inference methods that can deal with the outliers and incompleteness efficiently. In this paper, the authors propose a rank score test for quantile regression with fixed censored responses, based on the standard quantile regression in an informative subset which is computationally efficient and robust. The authors further select the informative subset by the multiply robust propensity scores, and then derive the asymptotic properties of the proposed test statistic under both the null and local alternatives. Moreover, the authors conduct extensive simulations to verify the validity of the proposed test, and apply it to a human immunodeficiency virus data set to identify the important predictors for the conditional quantiles of the censored viral load.

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