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Pre-heating temperature induced flowability and wax deposition characteristics of crude oil adding wax inhibitors

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Petroleum Science 2023年第4期20卷 2468-2478页

作者： bo Yao Hao-Ran Zhu Bao-dong Yan Chuan-Xian Li Fei Yang Guang-Yu Sun hong-bo Zeng College of Pipeline and Civil Engineering China University of PetroleumQingdaoShandong266580People's Republic of China Department of Chemical and Materials Engineering University of AlbertaEdmontonABT6G 1H9Canada School of Petroleum Engineering Changzhou UniversityChangzhouJiangsu213164People's Republic of China China Oil&Gas Pipeline Network Corporation Beijing100020China

This paper investigated the effects of pre-heating treatment temperatures(T_(pre))on the flowability and wax deposition characteristics of a typical waxy crude oil after adding wax *** is found that there is little difference in wax precipitation exothermic characteristics of crude oils at different T_(pre),as well as the wax crystal solubility coefficient in the temperature range of 25-30℃.For the undoped crude oil,the flowability after wax precipitation gets much improved and the wax deposition is alleviated as T_(pre)*** T_(pre)=50℃,the viscosity and wax deposition rate of crude oil adding wax inhibitors are higher than those of the undoped crude *** the T_(pre)increases to 60,70,and 80℃,the flowability of the doped crude oil are largely improved and the wax deposition is suppressed with the T_(pre)increase,but the wax content of wax deposit increases *** is speculated that,on the one hand,the T_(pre)increase helps the dispersion of asphaltenes into smaller sizes,which facilitates the co-crystallization with paraffin waxes and generates more aggregated wax crystal *** weakens the low-temperature gel structure and increases the solid concentration required for the crosslink to form the wax *** the other hand,the decrease in viscosity increases the diffusion rate of wax molecules and accelerates the aging of wax *** experimental results have important guiding significance for the pipeline transportation of doped crude oils.

关键词： Pre-heating treatment Wax inhibitor Flowability Wax deposition Waxy crude oil

H5N1 Avian Influenza Pre-pandemic Vaccine Strains in China

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Biomedical and Environmental Sciences 2014年第10期27卷 763-769页

作者： bo hong dong Li bo ZHANG Ye dong Jie ZOU Shu Mei GAO Rong Bao WANG Da Yan SHU Yue Long National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention Key Laboratory for Medical Virology National Health and Family Planning Commission

Objective To prepare the 4 candidate vaccine strains of H5N1 avian influenza virus isolated in China Methods Recombinant viruses were rescued using reverse genetics. Neuraminidase （NA） and hemagglutinin （HA） segments of the A/Xinjiang/1/2006, A/Guangxi/1/2009, A/Hubei/1/2010, and A/Guangdong/1/2011 viruses were amplified by RT-PCR. Multibasic amino acid cleavage site of HA was removed and ligated into the pCIpoll vector for virus rescue. The recombinant viruses were evaluated by trypsin dependent assays. Their embnjonate survival and antigenicity were compared with those of the respective wild-type viruses. Results The 4 recombinant viruses showed similar antigenicity compared with wild-type viruses, chicken embryo survival and trypsin-dependent characteristics. Conclusion The 4 recombinant viruses rescued using reverse genetics meet the criteria for classification of low pathogenic avian influenza strains, thus supporting the use of them for the development of seeds and production of pre-pandemic vaccines.

关键词： Influenza H5N1 Pre-pandemic Vaccine strains

Tight sandstone gas accumulation mechanisms and sweet spot prediction, Triassic Xujiahe Formation, Sichuan Basin, China

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Petroleum Science 2023年第6期20卷 3301-3310页

作者： Lin Jiang Wen Zhao dong-Mei bo Feng hong Yan-Jie Gong Jia-Qing Hao Research Institute of Petroleum Exploration and Development PetroChinaBeijing100083China

The prediction of continental tight sandstone gas sweet spots is an obstacle during tight sandstone gas exploration. In this work, the classic physical fluid charging experimental equipment is improved, the combination of the gas migration and accumulation process with the pore network numerical simulation method is investigated, and application of the permeability/porosity ratio is proposed to predict the gas saturation and sweet spots of continental formations. The results show that (1) as the charging pressure increases, the permeability of the reservoir increases because more narrow pore throats are displaced in the percolation process;and (2) based on pore network numerical simulation and theoretical analysis, the natural gas migration and accumulation mechanisms are revealed. The gas saturation of tight sandstone rock is controlled by the gas charging pressure and dynamic percolation characteristics. (3) The ratio of permeability/porosity and fluid charging pressure is proposed to predict the gas saturation of the formation. The ratio is verified in a pilot and proven to be applicable and practical. This work highlights the tight sandstone gas migration and accumulation mechanisms and narrows the gap among microscale physical experiments, numerical simulation research, and field applications.

关键词： Tight sandstone gas Hydrocarbon migration and accumulation Physical experiment Numerical simulation

Smart metasurface with self-adaptively reprogrammable functions

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Light(Science & Applications) 2019年第1期8卷 266-277页

作者： Qian Ma Guo dong Bai hong bo Jing Cheng Yang Lianlin Li Tie Jun Cui State Key Laboratory of Millimeter Wave Southeast University210096 NanjingChina Jiangsu Cyber-Space Science&Technology Co. Ltd.12 Mozhou East Road211111 NanjingChina State Key Laboratory of Advanced Optical Communication Systems and Networks Department of ElectronicsPeking University100871 BeijingChina

Intelligence at either the material or metamaterial level is a goal that researchers have been *** passive to active,metasurfaces have been developed to be programmable to dynamically and arbitrarily manipulate electromagnetic(EM)***,the programmable metasurfaces require manual control to switch among different ***,we put forth a smart metasurface that has self-adaptively reprogrammable functionalities without human *** smart metasurface is capable of sensing ambient environments by integrating an additional sensor(s)and can adaptively adjust its EM operational functionality through an unmanned sensing feedback *** an illustrative example,we experimentally develop a motion-sensitive smart metasurface integrated with a three-axis gyroscope,which can adjust self-adaptively the EM radiation beams via different rotations of the *** develop an online feedback algorithm as the control software to make the smart metasurface achieve single-beam and multibeam steering and other dynamic reactions *** proposed metasurface is extendable to other physical sensors to detect the humidity,temperature,illuminating light,and so *** strategy will open up a new avenue for future unmanned devices that are consistent with the ambient environment.

关键词： surface ambient adjust

Morphological evolution of tunnel tips for aluminum foils during DC etching

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International Journal of Minerals,Metallurgy and Materials 2013年第10期20卷 961-966页

作者： Li-bo Liang Ye-dong He hong-zhou Song Xiao-fei Yang Xiao-yu Cai School of Materials Science and Engineering University of Science and Technology Beijing Institute of Technology Research and Development of Electronic Aluminium Foil Guangxi Hezhou Guidong Electronics TechnologyCo.Ltd.

The morphologies of tunnel tips in different stages for aluminum foils during DC etching in 1.5 mol/L HC1 solution at 90℃ were observed by field emission scanning electron microscopy （FE-SEM）. A novel model was proposed to describe the morphological evolution of tunnel tips throughout the growth processes. In the pit nucleation stage, the pits vary from the hemispherical to half-cubic shapes due to the activation of pit tips from the center to the edge. During the tunnel growth stage, the pits dissolve toward the depth direction and develop into the tunnels, and their tips remain flat. In the tip passivation stage, as the passivation of tunnel tips speeds up from the edge to the center＇s the tunnel tips change from flat shapes to three-dimensional protrusions. The mechanism may be attributed to the order of activation or passivation on the tunnel tips changed in different stages.

关键词： aluminum corrosion pitting polarization etching electrolytic capacitors

Coating mechanism of nano-TiO_2 films on the surface of ultra-fine calcined coal kaolin particles

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International Journal of Minerals,Metallurgy and Materials 2011年第4期18卷 487-493页

作者： Hai Lin Ying-bo dong School of Civil and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China

A new type of mineral composite was made by calcined coal *** interaction mechanism of an inorganic modification reagent TiOSO4 with the surface of ultra-fine calcined coal kaolin particles（substrate） was studied by X-ray photoelectron *** results show that chemisorption exists in the phase boundary between the modification agent and the substrate surface,while physical adsorption occurs on the modification layers of hydrate titanium *** interaction force was calculated and analyzed according to DLVO theory between ultra-fine calcined coal kaolin particles and hydrate titanium dioxide nano-particles in the modification *** is shown that the both electrostatic force and van der Waals force are attractive,and the coacervation between ultra-fine calcined coal kaolin particles and hydrate titanium dioxide nano-particles leads to the coating of hydrate titanium dioxide on the surface of ultra-fine calcined coal kaolin particles.

关键词： calcined coal kaolin titanium dioxide coatings modification mechanisms

Enhanced hydrogen evolution reaction in FePt film with remanence due to decrease in domain walls

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Rare Metals 2024年第3期43卷 1108-1115页

作者： hong hong dong-Xue Liu Jun Li Jun-Ming Li Li-Qian Wu bo Yang Qing-Qi Cao Dun-Hui Wang National Laboratory of Solid State Microstructures Collaborative Innovation Center of Advanced MicrostructuresJiangsu Provincial Key Laboratory for NanotechnologySchool of PhysicsNanjing UniversityNanjing210093China Hangzhou Dianzi University Hangzhou310018China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang110819China

As an effective strategy to improve the properties of electrocatalysts,magnetic field-assisted electrocatalytic water splitting has attracted increasing attention ***,the corresponding enhancements mostly depend on the exertion of an external magnetic field during electrochemical reactions,which results in a high cost of industrial production,and makes the magnetic field manipulation of electrocatalysis become a challenging *** this work,instead of the external magnetic field,a bias magnetic field is self-supplied by the remanence state of a ferromagnetic electrocatalyst of *** to the assistance of this bias magnetic field,the FePt film in the remanence state shows the overpotential of 229 mV during hydrogen evolution reaction,which is much lower than that in its demagnetization state(283 mV).Our findings demonstrate that the remanence in ferromagnetic electrocatalysts can improve the catalytic performance,which is attributed to the decrease in domain walls.

关键词： Remanence Magnetic domains Electrocatalysis Hydrogen evolution reaction(HER)

Double glow plasma carburization on zirconium to improve surface hardness and wear resistance

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Rare Metals 2017年第7期36卷 569-573页

作者： Jian-Qing Wang hong-bo Yang Bing Zhang Wei Xi Ze dong Qin Jing State Key Laboratory o'f Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

Though some important progress in the excel- lent mechanical properties of zirconium alloys have been reported, their high surface hardness and good wear prop- erties need to be explored further. In this work, a carbur- ized layer was formed on the surface of commercially pure zirconium by a double glow plasma hydrogen-free car- burizing technique. Commercial high-purity graphite was used as the carbon source material. X-ray diffraction （XRD）, scanning electron microscopy （SEM）, energy dis- persive spectroscopy （EDS）, Vickers hardness test, friction and wear test were used to characterize the samples car- burized. The carburized layer could be clearly observed under a microscope. XRD patterns indicate that the zirco- nium carbide phase is formed in the carburized layer. The surface hardness of the sample increases significantly after carburization. Friction and wear tests results show that wear resistance and friction coefficient of zirconium are improved considerably after carburization. Surface plastic deformation is arrested to a low extent in contrast with pure zirconium because of the presence of ZrC phases during the wear test. The results may provide new insight into methods for surface strengthening of zirconium alloys.

关键词： Zirconium alloys Carburization Hardness Wear resistance

Formation and Structural Evolution of Fe72.5B15.6Si7.8Nb1.7Zr1.7Cu0.7 Nanocrystalline Alloy

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Acta Metallurgica Sinica(English Letters) 2020年第2期33卷 313-318页

作者： Yao-Xiang Geng hong-Yu Ding dong-Peng Wang Zhi-Jie Zhang hong-bo Ju Li-Hua Yu Jun-Hua Xu School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Marine Equipment and Technology Institute Jiangsu University of Science and TechnologyZhenjiang 212003China

A 2.5-mm Fe72.5B15.6Si7.8Nb1.7Zr1.7Cu0.7 glassy rod was successfully fabricated using copper mold *** introduction of Cu resulted in the formation of large quantities of a-Fe nanoparticles embedded in the glassy matrix after isothermal *** Fe72.5B15.6Si7.8Nb1.7Zr1.7Cu0.7 nanocrystalline alloy exhibited high saturation magnetization(~1.26 T) and a low coercive force(~0.8 A/m) after annealing at 833 K for 15 min due to the precipitation of ~15-nm-sized a-Fe nanoparticles in the glassy *** structural evolution of the FeBSiNbZrCu amorphous alloy during the annealing process was discussed using a dual-cluster model.

关键词： Nanocrystalline alloy Magnetic property Dual-cluster model Structural evolution