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化工过程非稳态开工的缓冲升温修正切换控制

化工学报 2015年第2期66卷 647-654页

作者：罗雄麟左瑞香冯爱祥许锋中国石油大学自动化系北京102249

化工过程的开工大多表现为一个升温过程。为满足升温过程的快速性而又不失稳定性的要求,有学者提出将时间最优Bang-Bang控制与其他控制方法结合来控制升温过程,但由于Bang-Bang控制对切换次数和切换点要求严格,致使其在实际应用中不够... 详细信息

化工过程的开工大多表现为一个升温过程。为满足升温过程的快速性而又不失稳定性的要求,有学者提出将时间最优Bang-Bang控制与其他控制方法结合来控制升温过程,但由于Bang-Bang控制对切换次数和切换点要求严格,致使其在实际应用中不够理想。在Bang-Bang组合控制的基础上引入缓冲升温控制,将整个控制系统分为4部分:全幅升温、全幅降温、缓冲升温、PID控制。将温度变化率作为缓冲升温与PID控制的切换变量,将修正切换控制问题等价为非线性规划问题,优化选取全幅升温、全幅降温、缓冲升温最优切换时间点。实例对比分析表明,该切换开工控制方案不仅避免了因切换次数与切换点选取不当导致的不良问题,且超调小,稳定快。

关键词：过程控制开工控制修正切换控制非线性规划

Modulated noble metal/2D MOF heterostructures for improved hydrogen storage of MgH_(2)

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Rare Metals 2024年第4期43卷 1672-1685页

作者： Zeng-Yi Li Li-Xian Sun Fen Xu Yu-Mei luo Yong-Peng Xia Sheng Wei Chen-Chen Zhang Ri-Guang Cheng Chao-feng Ye Meng-Yuan Liu Ju-Lan Zeng Zhong Cao Hong-Ge Pan School of Material Science and Engineering Guilin University of Electronic TechnologyGuilin541004China School of Chemistry and Chemical Engineering Changsha University of Science and TechnologyChangsha410114China Institute of Science and Technology for New Energy Xi’an Technological UniversityXi’an710021China

The conjugation of external species with twodimensional(2D)materials has broad application *** this study,we have explored the potential of noble metal/2D MOF heterostructures in hydrogen ***,the MgH_(2)-Ni-MOF@Pd system has shown remarkable hydrogen desorption/sorption performances,starting to liberate hydrogen at 1810C,which is 2300C lower than that of pristine *** the catalytic effect of Ni-MOF@Pd,the dehydrogenation apparent activation energy of MgH2 is noticeably decreased from(133.5±17.5)to(34.58±1.87)kJ·moL^(-1),and the hydrogenation apparent activation energy is reduced from(70.41±7.43)to(25.78±4.64)kJ·moL^(-1),which is lowered by 63.4%.The fully-dehydrogenated MgH2-NiMOF@Pd composite rapidly uptakes hydrogen,with 2.62wt%at 100℃and 6.06 wt%at 150℃within 300 s,*** mechanism analysis of MgH2 catalyzed by Ni-MOF@Pd has revealed that the transformation of Mg_2Ni and Mg_2NiH_4 could act as a"hydrogen pump",providing numerous channels for fast diffusion and transport of hydrogen ***,in the dehydrogenation process,the element Pd reacts with MgH_(2)to form the MgPd alloy phase,which makes MgH_(2)take precedence to decompose through the Mg-Pd alloy rather than self-decomposition,further reducing thermal stability and improving de/hydrogenation *** synergistic effect of Mg-Pd,Mg_2Ni,and the special ultra-thin 2D sheet structure of the additive is the main reason for the good hydrogen storage property of MgH_(2)-Ni-MOF@*** findings provide inspiration for designing efficient multifunctional additives with unique morphologies to optimize the hydrogen desorption/sorption behaviors of hydrogen storage materials.

关键词： Hydrogen storage Magnesium hydride 2D metal-organic framework nanosheets Ni/Pd Synergistic catalysis

MODELING ON DYNAMIC PROCESS OF MEMBRANE FOULING DURING FINITE CROSSFLOW ULTRAFILTRATION IN CHARGED SYSTEM

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Journal of Hydrodynamics 2006年第2期18卷 206-210页

作者： luo Ming-Liang PU Chun-sheng ZHAO Jian-qing College of Petroleum Engineering China University of Petroleum （East China） Dongying 257061 China College of Materials Science and Engineering South China University of Technology Guangzhou 510640 China

Flux decline during finite crossflow Ultrafiltration（UF） in charged system was investigated by perceiving membrane fouling as a dynamic process from non-equilibrium to equilibrium. Under the influence of the boundary condition at the initial section and cross flow, the equilibrium is first reached at the initial section of the crossflow filter and the front of the equilibrium region progresses with time toward the end of the filter. A mathematic model was developed to describe this dynamic process of membrane fouling in a charged system. With the model, the time-dependent flux and the time required to reach the steady state in a crossflow filtration can be easily determined. The fouling process under different conditions is simulated as illustrated with a demonstration of the newly developed model. The resulls of simulation show that there are jumps in the local flux at the front of the equilibrium region and the electrokinetic properties of charged UF system have a very substantial influence on the separation performance of membrane.

关键词： fouling dynamics flux decline,Ultrafiltration(UF) charged system modeling

Role of Suprapermafrost Groundwater Recharge in Dissolved Organic Carbon Dynamics of Thermokarst Lakes

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Journal of Earth Science 2024年第6期35卷 2175-2179页

作者： Zeyong Gao Fujun Niu Dongliang luo Yibo Wang Jing luo Guoan Yin Yunhu Shang Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China School of Environmental and Geographical Sciences Shanghai Normal UniversityShanghai200234China College of Earth and Environment Sciences Lanzhou UniversityLanzhou730000China

0 INTRODUCTION The Sixth Assessment Report of the Intergovernmental Panel on Climate Change(IPCC AR6)indicated that the global surface temperature had risen by approximately 1.09℃compared to the 1850-1900 average over the past decade(IPCC,2021).The warming rate of air temperature in polar and high-elevation permafrost regions was found to be about two times higher than the average global warming rate(Liu et al.,2023;Hu et al.,2021).

关键词： warming karst global

Oral delivery of ferroptosis inducers for effective treatment of hepatic fibrosis

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Nano Research 2024年第8期17卷 7621-7630页

作者： Yinglan Yu Shunlong Zhang Yongfeng Xu Hao Shao Lei luo College of Pharmaceutical Sciences Southwest UniversityChongqing 400715China

Liver fibrosis is characterized by the excessive accumulation of extracellular matrix(ECM),which is primarily produced by activated hepatic stellate cells(HSCs).However,effective therapies for hepatic fibrosis are currently *** is a promising anti-fibrotic drug candidate,but its clinical application is hindered by limited ***,we present a novel oral delivery platform that enhances the HSCs uptake of artesunate and induces potent *** platform is vitamin Adecorated nanoparticles encapsulated with *** multifunctional ligand vitamin A interacts with retinol-binding proteins that are highly expressed on the intestinal epithelium to promote transcytosis,highly expressed on the surface of HSCs but lowly expressed in normal *** oral administration,this oral delivery platform enhances transepithelial transport in the intestine,improves drug accumulation in the liver,and continuously increases HSCs uptake of *** drug release in HSCs,artesunate depletes glutathione peroxidase 4 and glutathione,effectively initiating *** vivo experiments demonstrate that this strategy induces pronounced ferroptosis,efficiently relieving liver *** work provides a proof-ofconcept demonstration that an oral delivery strategy for ferroptosis inducers may be beneficial for liver fibrosis treatment.

关键词： liver fibrosis hepatic stellate cells oral delivery intestinal epithelium ferroptosis

Molecular behaviors in thin film lubrication——Part one: Film formation for different polarities of molecules

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Friction 2019年第4期7卷 372-387页

作者： Shaohua ZHANG Yijun QIAO Yuhong LIU Liran MA Jianbin luo State Key Laboratory of Tribology Tsinghua UniversityBeijing100084China Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of ControlEngineeringBeijing100094China

There are three unsolved problems in thin film lubrication(TFL) since it was proposed 20 years ago, i.e., the determination of the type of molecules that can enter the contact region efficiently during sliding, the orientation of molecules in the contact region, and the effect of solid surfaces on the liquid molecular orientation in TFL. In order to answer the first two questions, an in situ measurement system comprising a self-designed Raman microscopy and relative optical interference intensity(ROⅡ) system was set up to study the molecular behaviors. A variety of binary mixtures were used as lubricants in the test, and the concentration distribution profile and orientation of the additive molecules in TFL were characterized. The molecular behavior was determined via a combination of shearing, confinement, and surface adsorption. Furthermore, the difference in molecular polarity resulted in different competing effect of surface adsorption and intermolecular interaction, the influence of which on molecular behavior was discussed. Polar additive molecules interacted with the steel surface and exhibited an enrichment effect in the Hertz contact region when added into a nonpolar base oil. No enrichment effect was observed for nonpolar molecules that were added into the nonpolar base oil and polar molecules added into polar base oil. The enrichment of additive molecules enhanced the film-forming ability of the lubricant and resulted in a reduction in the friction coefficient of up to 61%. The orderly arrangement of the additive molecules was another reason for the friction-reducing. A binary multilayer model was proposed to illuminate the molecular behavior in the TFL, and the model was supported by contrary experiment results in elastohydrodynamic lubrication. This research may aid in understanding the nanoscale lubrication mechanism in TFL and the development of novel liquid lubricants.

关键词： thin film lubrication in situ Raman spectroscopy molecular distribution molecular orientation

Observation of the supercritical Pearl River plume front under the downwelling-favorable winds

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Science China Earth Sciences 2015年第11期58卷 2059-2066页

作者： BAI Peng GU YanZhen luo Lin ZHANG WanLei FAN KaiGuo College of Physical and Environmental Oceanography Ocean University of China College of Information Science and Engineering Ocean University of China Institute of Space and Earth Information Science Chinese University of Hong Kong State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences Qinhuangdao Marine Environmental Monitoring Central Station of SOA 91039 Army PLA

For the Pearl River plume, the supercritical, distinct plume front appears in downwelling-favorable winds, which is easily observed due to the distinct boundary between the plume water and the ambient water. In this paper, in situ and satellite observations of a plume front are utilized to explore the Pearl River plume front properties under the downwelling-favorable winds. Field observations clearly show frontal structure, especially the two-layer structure in the plume water and the downward-motion of water in the frontal region. The Advanced Synthetic Aperture Radar(ASAR) images are also analyzed to unveil the plume front: there is a white stripe on the west side out of the river mouth under downwelling-favorable winds, which is identified as a supercritical plume front, and the width of the plume front is about 250 m. The normalized velocity gradient shows the intense velocity convergence in the front region. Also, analyses of ASAR images imply that the river discharge plays an important role in controlling the location and shape of the front.

关键词： cruise observations Pearl River plume front ASAR winds

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城市群发展战略下中心城市金融溢出效应研究

云南财经大学学报 2020年第7期36卷 17-27页

作者：罗小伟中国人民银行西安分行营管部西安710002

随着中国经济迈入高质量发展新阶段,以京津冀、长三角、珠三角等为代表的城市群协同发展战略,更广泛地促进要素流动、更有效地配置资源及更有力地支撑经济高质量发展。以城市群协调发展战略为背景,分析中心城市对周边城市金融溢出效应... 详细信息

随着中国经济迈入高质量发展新阶段,以京津冀、长三角、珠三角等为代表的城市群协同发展战略,更广泛地促进要素流动、更有效地配置资源及更有力地支撑经济高质量发展。以城市群协调发展战略为背景,分析中心城市对周边城市金融溢出效应的作用机制,进而构建一个将中心城市金融溢出效应作为重要变量的周边城市金融业内生增长模型,然后运用空间滞后模型(SLM)和空间杜宾模型(SDM)实证检验城市群发展战略下中国中心城市对周边城市金融空间溢出效应。结果显示:2000—2017年间,九大国家中心城市金融产业发展对周围城市金融业增长具有显著的正向空间溢出效应,但东中西部城市群却存在明显的差异性。因此,推进城市群协同发展应该统筹兼顾一体化与差异化。

关键词：城市群发展中心城市金融发展空间溢出效应

QTL Mapping for Hull Thickness and Related Traits in Hybrid Rice Xieyou 9308

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Rice science 2014年第1期21卷 29-38页

作者： luo Li-li ZHANG Ying-xin CHEN Dai-bo ZHAN xiao-deng SHEN Xi-hong CHENG Shi-hua CAO Li-yong National Center for Rice Improvement China National Rice Research Institute College of Life and Environmental Sciences Hangzhou Normal University

We conducted a quantitative trait locus （QTL） analysis of 165 rice recombinant inbred lines derived from a cross between Zhonghui 9308 （Z9308） and Xieqingzao B （XB） in Hainan and Hangzhou, China. Grain thickness （GT）, brown rice thickness （BRT）, hull thickness （HT） and milling quality were used for QTL mapping. HT was significantly and positively correlated with GT and BRT. Twenty-nine QTLs were detected with phenotypic effects ranging from 2.80% to 21.27%. Six QTLs, qGT3, qBRT3, qBRT4, qHT6.1, qHT8 and qHT11, were detected repeatedly across two environments. Inherited from XB qHT6.1, qHT8 and qHT11 showed stable expression, explaining 9.92%, 21.27% and 10.83% of the phenotypic variances in Hainan and 9.61%, 6.40% and 6.71% in Hangzhou, respectively. Additionally, the QTL cluster between RM5944 and RM5626 on chromosome 3 was probably responsible for GT and milling quality. The cluster between RM6992 and RM6473 on chromosome 4 played an important role in grain filling. Three near isogenic lines （NILs）, X345, X338 and X389, were selected because they contained homozygous fragments from Zhonghui 9308, corresponding to qHT6.1, qHT8 and qHT11, respectively. The hull of XB was thicker than those of X345, X338 and X389. In all the lines, qHT6.1, qHT8 and qHT11 that regulated rice HT were stably inherited with obvious genetic effects.

关键词： rice hull thickness milling quality QTI_ mapping