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Exploring the mechanisms of calcium carbonate deposition on various substrates with implications for effective anti-scaling material selection

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Petroleum Science 2024年第4期21卷 2870-2880页

作者： Lu Gong Fei-Yi Wu Ming-Fei Pan Jun Huang Hao Zhang Jing-Li Luo hong-bo zeng College of Science China University of Petroleum Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of Petroleum Basic Research Center for Energy Interdisciplinary College of Science China University of Petroleum Department of Chemical and Materials Engineering University of Alberta Key Laboratory of High Efficiency and Clean Mechanical Manufacture (Ministry of Education) School of Mechanical Engineering Shandong University

The unexpected scaling phenomena have resulted in significant damages to the oil and gas industries,leading to issues such as heat exchanger failures and pipeline clogging. It is of practical and fundamental importance to understand the scaling mechanisms and develop efficient anti-scaling strategies. However,the underlying surface interaction mechanisms of scalants(e.g., calcite) with various substrates are still not fully understood. In this work, the colloidal probe atomic force microscopy(AFM) technique has been applied to directly quantify the surface forces between calcite particles and different metallic substrates,including carbon steel(CR1018), low alloy steel(4140), stainless steel(SS304) and tungsten carbide,under different water chemistries(i.e., salinity and p H). Measured force profiles revealed that the attractive van der Waals(VDW) interaction contributed to the attachment of the calcium carbonate particles on substrate surfaces, while the repulsive electric double layer(EDL) interactions could inhibit the attachment behaviors. High salinity and acidic p H conditions of aqueous solutions could weaken the EDL repulsion and promote the attachment behavior. The adhesion of calcite particles with CR1018 and4140 substrates was much stronger than that with SS304 and tungsten carbide substrates. The bulk scaling tests in aqueous solutions from an industrial oil production process showed that much more severe scaling behaviors of calcite was detected on CR1018 and 4140 than those on SS304 and tungsten carbide, which agreed with surface force measurement results. Besides, high salinity and acidic p H can significantly enhance the scaling phenomena. This work provides fundamental insights into the scaling mechanisms of calcite at the nanoscale with practical implications for the selection of suitable antiscaling materials in petroleum industries.

关键词： Scaling phenomenon Metallic substrates Surface forces Bulk scaling tests

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Self-healing Hydrogelsand Underlying Reversible Intermolecular Interactions

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Chinese Journal of Polymer Science 2021年第10期39卷 1246-1261,I0005页

作者： Meng Wu Qiong-Yao Peng Lin-bo Han hong-bo zeng Department of Chemical&Materials Engineering University of AlbertaEdmontonAlberta T6G 1H9Canada College of Health Science and Environmental Engineering Shenzhen Technology UniversityShenzhen 518118China

Self-healing hydrogels have attracted growing attention over the past decade due to their biomimetic structure,biocompatibility,as well as enhanced lifespan and reliability,thereby have been widely used in various biomedical,electrical and environmental engineering *** feature article has reviewed our recent progress in self-healing hydrogels derived from mussel-inspired interactions,multiple hydrogen-bonding functional groups such as 2-ureido-4[1H]-pyrimidinohe(UPy),dynamic covalent bonds(eg,Schiff base reactions and boronic ester bonds).The underlying molecular basics of these interactions,hydrogel preparation principles,and corresponding performances and applications are *** underlying reversible intermolecular interaction mechanisms in these hydrogels were investigated using nanomechanical techniques such as surface forces apparatus(SFA)and atomic force microscopy(AFM),providing fundamental insights into the self-healing mechanisms of the *** remaining challenging issues and perspectives in this rapidly developing research area are also discussed.

关键词： Self-healing hydrogels Mussel-inspired Interaction Multiple hydrogen-bonding Dynamic covalent bonds Intermolecular forces

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High molecular weight guar gum assisted settling of fine solids in diluted bitumen:Effect of solvents

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Petroleum Science 2021年第6期18卷 1877-1886页

作者： Camila Santander Jing Liu Xiao-Li Tan Qi Liu hong-bo zeng Department of Chemical and Materials Engineering University of AlbertaEdmontonAB T6G 1H9Canada

As water-based extraction technologies for producing bitumen from oil sands have received increasing environmental concerns,developing non-aqueous extraction(NAE)technique is of both fundamental and practical ***,the relatively high concentration of fine solids trapped in the extracted bitumen presents an obstacle for pipeline transport as well as upgrading and refining *** research attempts to provide a solution to fine solids removal without using synthetic additives or affecting bitumen recovery from NAE ***,naturally hydrophilic additives(i.e.,water and high molecular weight guar gum(HGG)produced from Cyamopsiste tragonolobuosr ***.)were introduced to promote the settling of fine solids suspended in bitumen-solvent solution,and the effects of solvents(i.e.,toluene,cyclohexane and their mixtures)were systematically *** size distribution analyzed by the focused beam reflectance measurements confirmed that the addition of water and HGG could promote the agglomeration and settling of fine solids in all solvents ***,the size range and quantity of the agglomerates vary significantly with the solvent's aromatic *** mixtures demonstrate a superior performance on removing fine solids from bitumen over single ***,in a 3:2 toluene/cyclohexane mixture,the solid content was lowered from 0.66 wt%to 0.09 wt%.

关键词： Non-aquoues extraction Fine solids Guar gum Agglomeration Settling

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Optimization of flow uniformity control device for six-stream continuous casting tundish

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Journal of Iron and Steel Research International 2020年第9期27卷 1035-1044页

作者： Xin-gang Ai Dong Han Sheng-li Li hong-bo zeng Hui-ya Li Key Laboratory of Chemical Metallurgy Engineering Liaoning Province University of Science and Technology LiaoningAnshan 114051LiaoningChina

For a multistream tundish,the uniformity among the streams plays a significant role in the quality of molten *** to analyze the uniformity quantitatively and optimize structures of a multistream tundish is an important research content for a multistream tundish.A new approach was proposed to quantify the uniformity among the *** a physical study and a numerical study were carried out to optimize the structure of the diversion hole based on the prototype of a six-stream tundish in a steel *** the basis of average residence time,the uniformity of each flow was considered fully and then the optimal structure of the diversion hole was obtained by means of the comprehensive analysis of temperature field and velocity *** results show that the optimum structural parameters adopted for diversion holes are height of 20 mm,angle of 15°and diameter of 80 mm.

关键词： Multistream tundish Uniformity Diversion hole Physical simulation Numerical simulation

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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

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Flexible tuning of multifocal holographic imaging based on electronically controlled metasurfaces

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Photonics Research 2024年第1期12卷 61-69页

作者： OWEN zeng CHENXIA LI bo FANG ZHI hong XUFENG JING Institute of Optoelectronic Technology China Jiliang UniversityHangzhou 310018China Centre for THz Research China Jiliang UniversityHangzhou 310018China College of Metrology&Measurement Engineering China Jiliang UniversityHangzhou 310018China

Programmable hyper-coded holography has the advantage of being programmable as well as being flexibly *** coded metamaterials with excellent electromagnetic modulation capability and the ability to control the phase to modulate the spatial radiation field through external excitation in the form of switching can be used to realize low-cost digital *** design a 1-bit encoded programmable metasurface,which is electrically connected to control the PIN diode in the switching state and to switch the condition of each metasurface cell between“0”and“1.”Using the designed programmable metasurface,we can randomly encode the cell structure to realize single-focus focusing,multi-focusing,and simple holographic letter *** on the nonlinear holographic model,we employ the Gerchberg-Saxton improvement algorithm to modulate the energy distribution at the focus by adjusting the phase ***,we introduce the Fourier convolution principle to regulate the holographic imaging focus flexibly.

关键词： holographic letter excitation

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Switched-capacitor Based Seven-level boost Inverter with a Reduced Number of Devices

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 381-391页

作者： Weijie Lin Jun zeng bo Fu Zhixing Yan Junfeng Liu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China WISDRI Engineering&Research Incorporation Limited Wuhan 430074China Department of Energy Aalborg UniversityAalborg 9220Denmark School of Automation Science and Engineering South China University of TechnologyGuangzhou 510641China

The conventional multilevel inverters(MLIs)have the disadvantages of numerous devices,incapacity of boost,unbalance for capacitor’s voltage,high complexity for control,and *** by this issue,a seven-level boost inverter(7LBI)based on a switched capacitor is presented for singlephase applications in this *** proposed 7LBI using only seven transistors can achieve seven output levels,1.5 voltage gain,and natural balance of capacitors’voltages without sensors or other auxiliary methods,which illustrates its suitability for the applications of renewable energy *** configuration of topology and operating principles are illustrated in *** natural balance of capacitors and capacitance calculations are deduced as ***,the comparative study is conducted for different types of *** results illustrate the merits of the proposed 7LBI with respect to reduced devices,lower voltage stress,and less power ***,a simulation for the proposed 7LBI with PWM modulation is realized based on the theoretical analysis;an experimental prototype is also implemented,verifying multilevel output,boost ability,natural balance for switched capacitors,and performance of transient response.

关键词： Multilevel inverters voltage gain natural balance renewable energy generation reduced number of elements

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When smoke meets gut:deciphering the interactions between tobacco smoking and gut microbiota in disease development

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Science China(Life Sciences) 2024年第5期67卷 854-864页

作者： bo Chen Guangyi zeng Lulu Sun Changtao Jiang Center of Basic Medical Research Institute of Medical Innovation and ResearchPeking University Third HospitalBeijing 100191China Department of Physiology and Pathophysiology School of Basic Medical SciencesState Key Laboratory of Vascular Homeostasis and RemodelingPeking UniversityBeijing 100191China Center for Obesity and Metabolic Disease Research School of Basic Medical SciencesPeking UniversityBeijing 100191China State Key Laboratory of Women’s Reproductive Health and Fertility Promotion Peking UniversityBeijing 100191China Department of Endocrinology and Metabolism Peking University Third HospitalBeijing 100191China

Tobacco smoking is a prevalent and detrimental habit practiced worldwide,increasing the risk of various diseases,including chronic obstructive pulmonary disease(COPD),cardiovascular disease,liver disease,and *** previous research has explored the detrimental health effects of tobacco smoking,recent studies suggest that gut microbiota dysbiosis may play a critical role in these *** tobacco smoke components,such as nicotine,are found in the gastrointestinal tract and interact with gut microbiota,leading to lasting impacts on host health and *** review delves into the ways tobacco smoking and its various constituents influence gut microbiota composition and *** also summarize recent advancements in understanding how tobacco smoking-induced gut microbiota dysbiosis affects host ***,this review introduces a novel perspective on how changes in gut microbiota following smoking cessation may contribute to withdrawal syndrome and the degree of health improvements in smokers.

关键词： tobacco smoking gut microbiota dysbiosis nicotine smoking cessation

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Magneto-optical isotope enrichment of potassium-40 with transverse cooling

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Chinese Optics Letters 2024年第7期22卷 1-5页

作者： Shangjin Li Zixuan zeng bo Yan School of Physics Zhejiang UniversityHangzhou 310027China

Isotope shifts among different isotopes can be effectively addressed using narrow-linewidth lasers,facilitating laser isotope separation and achieving significant enrichment at a single *** separation of potassium isotopes,employing optical pumping and magnetic deflection,has proven to be *** further improve the enrichment of ^(40)K,we introduce 2D transverse cooling to minimize the divergence *** this modification,we demonstrate enrichment of ^(40)K,elevating it from 0.012%to 12%–20%.This represents an enrichment increase by three orders of magnitude,surpassing our previous result by one *** method is particularly well-suited for isotope enrichment of elements with extremely low abundance.

关键词： isotope separation potassium isotopes two-dimensional transverse cooling.

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Type Synthesis of Self-Alignment Parallel Ankle Rehabilitation Robot with Suitable Passive Degrees of Freedom

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 160-175页

作者： Ya Liu Wenjuan Lu Dabao Fan Weijian Tan bo Hu Daxing zeng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China Dongguan Engineering Technology Research Center for Parallel Robot Dongguan 523808China The DGUT Innovation Center of Robotics and Intelligent Equipment Dongguan 523808China

The current parallel ankle rehabilitation robot(ARR)suffers from the problem of difficult real-time alignment of the human-robot joint center of rotation,which may lead to secondary injuries to the *** study investigates type synthesis of a parallel self-alignment ankle rehabilitation robot(PSAARR)based on the kinematic characteristics of ankle joint rotation center drift from the perspective of introducing"suitable passive degrees of freedom(DOF)"with a suitable number and ***,the self-alignment principle of parallel ARR was proposed by deriving conditions for transforming a human-robot closed chain(HRCC)formed by an ARR and human body into a kinematic suitable constrained system and introducing conditions of"decoupled"and"less limb".Second,the relationship between the self-alignment principle and actuation wrenches(twists)of PSAARR was analyzed with the velocity Jacobian matrix as a"bridge".Subsequently,the type synthesis conditions of PSAARR were ***,a PSAARR synthesis method was proposed based on the screw theory and type of PSAARR synthesis ***,an HRCC kinematic model was established to verify the self-alignment capability of the *** this study,93 types of PSAARR limb structures were synthesized and the self-alignment capability of a human-robot joint axis was verified through kinematic analysis,which provides a theoretical basis for the design of such an ARR.

关键词： Ankle rehabilitation robot Self-alignment Parallel mechanism Type synthesis Screw theory

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