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Synthesis of crystals and particles by crystallization and polymerization in droplet-based microfluidic devices

Frontiers of Chemical Science and Engineering 2010年第1期4卷 26-36页

作者： Jingtao WANG Jin ZhanG junjie han School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

The recent advances in crystallization and polymerization assisted by droplet-based microfluidics to synthesize micro-particles and micro-crystals are reviewed in this ***-based microfluidic devices are powerful tools to execute some precise controls and operations on the flow inside microchannels by adjusting fluid dynamics parameters to produce monodisperse emulsions or multiple-emulsions of various *** features of this technique are producing particles of monodispersity to control the shape of particles in a new level,and to generate droplets of diverse materials including aqueous solutions,gels and *** microfluidic devices have been employed to generate monodisperse droplets of range from nm toμm,such as T junctions,flow-focusing devices and co-flow or cross-flow *** discrete,independently controllable droplets are ideal microreactors to be manipulated in the channels to synthesize the nanocrystals,protein crystals,polymer particles and *** generated monodisperse particles or crystals are to meet different technical demands in many fields,such as crystal engineering,encapsulation and drug delivery *** devices are promising tools in the synthesis of micron polymer particles that have diverse applications such as the photonic materials,ion-exchange and chromatography columns,and field-responsive rheological *** assisted by microfluidic devices are able to produce the polymer particles(including Janus particles)with precise control over their sizes,size distribution,morphology and *** technology of microfluidics has also been employed to generate core-shell microcapsules and solid microgels with precise controlled sizes and inner *** chosen“smart”materials are sensitive to an external stimulus such as the change of the pH,electric field and *** complex particles are also able to be functionalized by encapsulating nanoparticles of speci

关键词： microfluidics emulsion polymerization polymer particle micro-capsule drug delivery emulsion crystallization nucleation kinetics protein crystallization

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Fabrication and Evaluation of a Bioactive Sr–Ca–P Contained Micro-Arc Oxidation Coating on Magnesium Strontium Alloy for Bone Repair Application

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Journal of Materials Science & Technology 2016年第3期32卷 233-244页

作者： junjie han Peng Wan Yu Sun Zongyuan Liu Xinmin Fan Lili Tan Ke Yang Department of Materials Science and Engineering Nanjing University of Science & Technology Nanjing 210094 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China China Medical University Shenyang 110002 China

Considering the compatibility between degradation and bioactivity of magnesium-based implants for bone repair, micro-arc oxidation is used to modify the magnesium alloy surface in aqueous electrolytes, allowing strontium, calcium, and phosphorus to be incorporated into the coating. The thickness, composition, morphology and phase of this Sr-Ca-P containing coating are characterized by scanning electron microscopy equipped with energy dispersive X-ray spectrometer and X-ray diffraction. The in vitro and in vivo degradation of the coating is evaluated by immersion test, electrochemical test and implantation test. Moreover, the cytocompatibility is tested with osteoblast cell according to ISO 10993. The results show that St, Ca and P elements are incorporated into the oxide coating, and a refined structure with tiny discharging micro-pores is observed on the surface of the coating. The Sr-Ca-P coating possesses a better corrosion resistance in vitro and retards the degradation in vivo. Such coating is expected to have significant medical applications on orthopedic implants and bone repair materials.

关键词： Magnesium alloy Strontium Ca-P coating Degradation Micro-arc oxidation

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Acidity Evaluation of Industrially Dealuminated Y Zeolite via Methylcyclohexane Transformation

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China Petroleum Processing & Petrochemical Technology 2021年第3期23卷 50-57页

作者： Hou Kaige Qin Bo han junjie Du Yanze Ma Jinghong Li Ruifeng College of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024 SINOPEC Dalian Research Institute of Petroleum and Petrochemicals Dalian

The catalytic transformation of methylcyclohexane as an accepted probe reaction to evaluate zeolitic acidity(concentration,strength,and accessibility)is employed to study the acidity and the reactivity of three commercial dealuminated Y zeolites(DAY)with different Si/Al ratios and meso/microporosities,with their properties analyzed by N_(2) adsorption/desorption,pyridine-IR,and hydroxyl-IR spectroscopy *** global activity(conversion)is largely dependent on the concentration of the acid sites,and the activity of the protonic sites in terms of turnover frequency(TOF)reflects the accessibility of acid *** products of aromatics and isomers,and the yield of cracking products increase with the increase of concentration of strong protonic sites in zeolite ***,the decrease of aromatics with the reduction of the concentration of acid sites and the diffusion length within DAY zeolites are observed due to the decrease of the secondary *** the same reason,it results in the increasing of C_(7)products and alkenes/alkanes ratios in the cracking *** high i-C_(4)product selectivity is a unique reflection of the high percentage of very strong acid sites,which is characterized by the hydroxyl-IR band at 3600 cm^(-1).

关键词： methylcyclohexane catalytic transformation industrially modified Y zeolite zeolitic acidity strong protonic sites spectroscopic technology

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Review of PPP-RTK:achievements,challenges,and opportunities

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Satellite Navigation 2022年第3期3卷 16-37,I0002页

作者： Xingxing Li Jiaxin Huang Xin Li Zhiheng Shen junjie han Linyang Li Bo Wang School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan430079HubeiChina Technische Universitat Berlin(TUB) Straße Des 17.Juni10623BerlinGermany China Railway Siyuan Survey and Design Group Co. Ltd.WuhanChina

The PPP–RTK method,which combines the concepts of Precise of Point Positioning(PPP)and Real-Time Kinematic(RTK),is proposed to provide a centimeter-accuracy positioning service for an unlimited number of ***,the PPP–RTK technique is becoming a promising tool for emerging applications such as autonomous vehicles and unmanned logistics as it has several advantages including high precision,full flexibility,and good *** paper gives a detailed review of PPP–RTK focusing on its implementation methods,recent achievements as well as challenges and ***,the fundamental approach to implement PPP–RTK is described and an overview of the research on key techniques,such as Uncalibrated Phase Delay(UPD)estimation,precise atmospheric correction retrieval and modeling,and fast PPP ambiguity resolution,is ***,the recent efforts and progress are addressed,such as improving the performance of PPP–RTK by combining multi-GNSS and multi-frequency observations,single-frequency PPP–RTK for low-cost devices,and PPP–RTK for vehicle ***,the system construction and applications based on the PPP–RTK method are ***,the main issues that impact PPP–RTK performance are highlighted,including signal occlusion in complex urban areas and atmosphere modeling in extreme weather *** new opportunities brought by the rapid development of low-cost markets,multiple sensors,and new-generation Low Earth Orbit(LEO)navigation constellation are also ***,the paper concludes with some comments and the prospects for future research.

关键词： PPP–RTK Ambiguity resolution Multi-GNSS Smart device Multi-sensor fusion

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A BOOSTING APPROACH FOR INTRUSION DETECTION

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Journal of Electronics(China) 2007年第3期24卷 369-373页

作者： Zan Xin han Jiuqiang Zhang junjie Zheng Qinghua han Chongzhao Dept of Automation School of Electronics and Information Engineering Xi＇an Jiaotong University Xi＇an 710040 China

Intrusion detection can be essentially regarded as a classification problem,namely,dis-tinguishing normal profiles from intrusive behaviors. This paper introduces boosting classification algorithm into the area of intrusion detection to learn attack signatures. Decision tree algorithm is used as simple base learner of boosting algorithm. Furthermore,this paper employs the Principle Com-ponent Analysis (PCA) approach,an effective data reduction approach,to extract the key attribute set from the original high-dimensional network traffic data. KDD CUP 99 data set is used in these ex-periments to demonstrate that boosting algorithm can greatly improve the classification accuracy of weak learners by combining a number of simple “weak learners”. In our experiments,the error rate of training phase of boosting algorithm is reduced from 30.2% to 8% after 10 iterations. Besides,this paper also compares boosting algorithm with Support Vector Machine (SVM) algorithm and shows that the classification accuracy of boosting algorithm is little better than SVM algorithm’s. However,the generalization ability of SVM algorithm is better than boosting algorithm.

关键词： Network security Intrusion Detection System (IDS) Machine learning Boosting algo-rithm Decision tree Support Vector Machine (SVM)

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Reconstitution of biosynthetic pathway for mushroom-derived cyathane diterpenes in yeast and generation of new“non-natural”analogues

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Acta Pharmaceutica Sinica B 2021年第9期11卷 2945-2956页

作者： Ke Ma Yuting Zhang Cui Guo Yanlong Yang junjie han Bo Yu Wenbing Yin Hongwei Liu State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Savaid Medical School University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Microbial Physiological and Metabolic Engineering Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

Mushroom-derived cyathane-type diterpenes possess unusual chemical skeleton and diverse *** efficiently supply bioactive cyathanes for deep studies and explore their structural diversity,de novo synthesis of cyathane diterpenes in a geranylgeranyl pyrophosphate engineered Saccharomyces cerevisiae is *** by homologous analyses,one new unclustered FAD-dependent oxidase EriM accounting for the formation of allyl aldehyde and three new NADP(H)-dependent reductases in the biosynthesis of cyathanes are identified and *** combinatorial biosynthetic strategy,*** strains generating twenty-two cyathane-type diterpenes,including seven"unnatural"cyathane xylosides(12,13,14a,14b,19,20,and 22)are *** 12-14,19,and 20 show significant neurotrophic effects on PC 12 cells in the dose of 6.3-25.0μmol/*** studies provide new insights into the divergent biosynthesis of mushroom-originated cyathanes and a straightforward approach to produce bioactive cyathane-type diterpenes.

关键词： Cyathane-type diterpene Biosynthesis Heterologous expression Non-enzymatic reaction

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Immunogenic molecules associated with gut bacterial cell walls:chemical structures,immune-modulating functions,and mechanisms

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Protein & Cell 2023年第10期14卷 776-785页

作者： Ruopeng Yin Tao Wang Huanqin Dai junjie han Jingzu Sun Ningning Liu Wang Dong Jin Zhong Hongwei Liu State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Savaid Medical School University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of Sciences100101 BeijingChina

Interactions between gut microbiome and host immune system are fundamental to maintaining the intestinal mucosal barrier and *** the host-gut microbiome interface,cell wall-derived molecules from gut commensal bacteria have been reported to play a pivotal role in training and remodeling host immune *** this article,we review gut bacterial cell wall-derived molecules with characterized chemical structures,including peptidoglycan and lipid-related molecules that impact host health and disease processes via regulating innate and adaptive ***,we aim to discuss the structures,immune responses,and underlying mechanisms of these immunogenic *** on current advances,we propose cell wall-derived components as important sources of medicinal agents for the treatment of infection and immune diseases.

关键词： gut commensal bacteria peptidoglycan lipid-related molecules immune responses

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Ganoboninketal C from Ganoderma boninense improves the efficacy of CDDP-based chemotherapy through inhibiting translesion DNA synthesis

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Food Science and Human Wellness 2024年第5期13卷 2982-2992页

作者： Xiaolu Ma Fei Yang Ke Ma Hongyan Shen junjie han Kai Wang Yeran Yang Jiawei Zhu Ruiyuan An Qilin Wang Tie-Shan Tang Bo Zhou Hongwei Liu Caixia Guo College of Biomedical Engineering Taiyuan University of TechnologyTaiyuan 030024China CAS Key Laboratory of Genomics and Precision Medicine Beijing Institute of Genomics/China National Center for BioinformationUniversity of Chinese Academy of SciencesChinese Academy of SciencesBeijing 100101China State Key Laboratory of Membrane Biology Institute of ZoologyUniversity of Chinese Academy of SciencesChinese Academy of SciencesBeijing 100101China Institute of Microbiology University of Chinese Academy of SciencesChinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100101China

Translesion DNA synthesis(TLS)can bypass DNA lesions caused by chemotherapeutic drugs,which usually result in drug *** its key role in mutagenesis and cell survival after DNA damage,inhibition of the TLS pathway has emerged as a potential target for improving the efficacy of DNA-damaging agents such as cisplatin(CDDP),a widely used anticancer ***,few suitable natural TLS inhibitors have been ***,we found that a triterpenoid compound Ganoboninketal C(26-3)from Ganoderma boninense,a traditional Chinese medicine,can impair CDDP-induced TLS polymerase eta(Polη)focus formation,PCNA monoubiquitination as well as ***,26-3 can significantly sensitize tumor cells to CDDP killing and reduce the proportion of cancer stem cells in AGS and promote apoptosis after CDDP ***,26-3 can also sensitize tumor cells to Gefitinib ***,through RNA-seq analysis,we found that 26-3 could abrogate the CDDP-induced upregulation of Polηand PIDD(p53-induced protein with a death domain),2 known factors promoting TLS ***,we found that activating transcription factor 3 is a potential novel TLS *** together,we have identified a natural TLS inhibitor 26-3,which can be potentially used as an adjuvant to improve clinical efficacy.

关键词： Ganoderma boninense Ganoboninketal C Cisplatin chemotherapy Translesion DNA synthesis

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Improvements of drilling fluid processing for cable-suspended electromechanical drills

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Global Geology 2013年第2期16卷 99-105页

作者： YU Dahui Pavel Talalay XU Huiwen CAO Pinlu Mikhail Sysoev han Lili han junjie Polar Research Center Jilin University College of Construction Engineering Jilin University

Deep ice drilling in Polar Regions plays a key role in paleo-climate, microbiological and glaciological researches. For deep ice and subglacial coring the special purpose-built electromechanical cable-suspended drills with bottom-hole circulation are designed and explored. Used at present drilling fluid circulation systems are specified by very high fluid wastes during processing. Measurements in deep drilling projects in Antarctic and Greenland ice sheets showed that 25%-40% of the drilling fluid, pumped into the hole, is retrieved to the surface with cable and drill, and up to 45% of retrieved fluid goes to waste. This leads not only to increasing of the fluid consumption and cost of the project in general but also to severe contamination of air, surface and near-surface snow-firn layers at the drilling site. In order to reduce wastes and environmental impact, it is proposed to modify drilling fluid processing system by avoiding of evaporation and leakages of fluid as far as practicable. Drilling fluid is prepared and pumped into the hole according to predetermined program on semiautomatic mode, and volume and density of blended and pumped into the hole drilling fluid are measured continuously. Components of the drilling fluid are stored and mixed in the special closed containers equipped by pressure relief valves. Separation of drilling fluid from ice cuttings is carried out by two steps: firstly, fluid is separated with hydro extractor and then with thermal separator. To reduce the amount of removed drilling fluid with cable special squeezing collar is installed on the borehole mouth. All these arrangements are able to decrease drilling fluid wastes in many times.

关键词： polar drilling drilling fluid cable-suspended electromechanical drill

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Development and test in grid of 630 kVA three-phase high temperature superconducting transformer

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Frontiers of Electrical and Electronic Engineering in China 2009年第1期4卷 104-113页

作者： Yinshun WANG Xiang ZHAO junjie han Huidong LI Yin GUAN Qing BAO Xi XU Shaotao DAI Naihao SONG Fengyuan ZhanG Liangzhen LIN Liye XIAO Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100080China Technical Center of Tebian Electric Apparatus Stock Co. LtdChangji 831100China Beijing Key Laboratory of High Voltage and EMC School of Electrical and Electronic EngineeringNorth China Electric Power UniversityBeijing 102206China

A 630-kVA 10.5 kV/0.4 kV three-phase high temperature superconducting(HTS)power transformer was successfully developed and tested in a live *** windings were wound by hermetic stainless steelreinforced multi-filamentary Bi2223/Ag *** structures of primary windings are solenoid with insulation and cooling path among layers,and those of secondary windings consist of double-pancakes connected in *** cryostat is made from electrical insulating glass fiber reinforced plastics(GFRP)materials with room temperature bore for commercial amorphous alloy core with five *** are laid in the toroidal cryostat so that the amorphous core operates at room *** insulation technology of double-half wrapping up the Bi2223/Ag tape with Kapton film is used by a winding machine developed by the *** characteristics of the transformer are obtained by standard short-circuit and no-load tests,and it is shown that the transformer meets operating requirements in a live grid.

关键词： high temperature superconducting(HTS)transformer Bi2223/Ag tape amorphous alloy windings liquid nitrogen

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