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Surface control of layered double hydroxides by in-situ initiating&terminating polymerization

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Nano Research 2022年第2期15卷 1538-1546页

作者： Dan Tong Yuquan Zhu Kaitao Li Kuilin Du Wendi Liu yanjun lin State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China School of Chemical Engineering Qinghai UniversityXining 810016China

Appropriate surface modification or functionalization is prerequisite for the application of inorganic *** surface control between organic and inorganic interface plays an important role in constructing organic-inorganic ***-situ polymerization has been extensively studied to improve the compatibility and dispersibility of inorganic nanoparticles,but the polymerized nanoparticles tend to concatenate and form large composites,restricting further ***,uniform and dense polyacrylic acid(PAA)membranes have been grafted on layered double hydroxide(LDH)nanosheets via an in-situ initiating and terminating radical graft polymerization *** initiating and terminating on the same particle,the size,morphology and density of grafted PAA onto the surface of LDHs can be controlled by adjusting the ratio of initiated sites to terminated sites,the amount of redox initiator or *** a result,with only 17.33%organic grafting ratio,PAA@LDHs with largely improved compatibility can be monodispersed in polyethylene(PE)and polyvinyl chloride(PVC)matrices,which is determined by a fluorescence microscope technique.

关键词： surface control in-situ polymerization organic-inorganic interface layered double hydroxides

Surface nucleation and independent growth of Ce（OH）4 within confinement space on modified carbon black surface to prepare nano-CeO2 without agglomeration

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Frontiers of Materials Science 2018年第2期12卷 168-175页

作者： Xinyue ZHANG Chunhui XIA Kaitao LI yanjun lin State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

Highly dispersed negative carboxyl groups can be formed on carbon black （CB） surface modified with strong nitric acid. Therefore positive cations can be uniformly absorbed by carboxyl groups and precipitated within a confinement space on modified CB surface to prepare highly dispersed nanomaterials. In this paper, the formation and dispersion status of surface negative carboxyl groups, adsorption status of Ce^3＋, surface confinement nucleation, crystallization and calcination process were studied by EDS, SEM, and laser particle size analysis. The results show that the carboxyl groups formed on modified CB surface are highly dispersed, and Ce^3＋ cations can be uniformly anchored by carboxyl groups. Therefore, highly dispersed Ce^3＋ can react with OH^- within a confinement surface region to form positive nano-Ce（OH）4 nuclei which also can be adsorbed by electrostatic attraction. After independent growth of Ce（OH）4 without agglomeration, highly dispersed CeO2 nanoparticles without agglomeration can be prepared together with the help of effectively isolates by CO2 released in the combustion of CB.

关键词： surface nucleation confinement space modified CB agglomeration nano-CeO2

Hydrophobic Interface Cages in Microemulsions:Concept and Experiment Using Tetraphenylethylene-based Double-tailed Surfactant

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Chemical Research in Chinese Universities 2021年第1期37卷 116-122页

作者： GUAN Weijiang TANG Xiaofang WANG Wei lin yanjun LU Chao State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029P.R.China

Although hydrophobic interface regions adjacent to water droplets play a vital role in microemulsion-based studies,their widespread applications have not been explicitly evoked owing to their small ***,we designed and synthesized a novel double-tailed anionic surfactant(TPE-di-C8SS)by linking the propeller-shaped tetraphenylethylene(TPE)with two octyl chains and an anionic sulfonate headgroup through a methoxy-butyl *** extra spacer and steric hindrance between rigid TPE groups can create the large cavities in hydrophobic interface regions,which we call the hydrophobic interface cages(HICs).The potentials and advantages of HICs in the easily-prepared TPE-di-C8SS microemulsion have been implemented by comparing the extraction efficiency towards cationic rhodamine B with Aerosol OT(AOT)*** results provided solid evidence that HICs rather than water droplets contributed to a higher extraction *** work not only proposes a concept of HICs but also provides a new perspective of their utilization in microemulsion-based applications.

关键词： Aggregation-induced emission Hydrophobic interface cage Tetraphenylethylene Microemulsion

剪力连接程度对冷弯U型组合梁抗弯承载力影响

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山东交通学院学报 2025年第1期33卷 35-42,52页

作者：林彦军张泽军张田涛山东省路桥集团有限公司山东济南250013 山东高速集团有限公司创新研究院山东济南250014 山东高速基础设施建设有限公司山东济南250014

为研究剪力连接程度对U型组合梁抗弯承载力的影响,根据剪力连接程度、剪力钉数、剪力钉间距等影响因素设计完成8组数值模型试验,采用验证后的有限元模型计算分析应变和挠度,根据中国、欧洲和美国等不同规范,分别计算完全剪力连接条件下... 详细信息

为研究剪力连接程度对U型组合梁抗弯承载力的影响,根据剪力连接程度、剪力钉数、剪力钉间距等影响因素设计完成8组数值模型试验,采用验证后的有限元模型计算分析应变和挠度,根据中国、欧洲和美国等不同规范,分别计算完全剪力连接条件下所需最少剪力钉数。结果表明:数值有限元模型能较好地模拟U型组合梁受力全过程中钢主梁和混凝土桥面板的应力及变形情况,实测结果与数值模拟计算结果相对差小于15%;剪力连接程度系数为0.02~0.30时,随剪力连接程度系数的增大,跨径16 m的U型组合梁的抗弯承载力不断增大,当剪力连接程度系数为0.30时,钢梁和混凝土已达到完全剪力连接,剪力连接程度系数大于0.30时,U型组合梁的抗弯承载力变化不大;U型组合梁抗弯承载力在弹性阶段的变化规律受剪力连接程度影响相对较小,工程应用中采用部分剪力连接可行,塑性阶段受剪力连接程度影响相对较大,U型组合梁抗弯承载力的计算与验算应计入剪力连接程度的影响;不同规范计算的完全剪力连接条件下所需最少剪力钉数较接近。

关键词： U型组合梁抗弯承载力数值模型试验剪力连接程度系数

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Preparation of Bimodal Mesoporous Silica Molecular Sieves from Organotrialkoxysilane and Tetraethoxysilane

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Petroleum Science 2007年第4期4卷 94-99页

作者： Gong yanjun Mu lin Dou Tao Key Laboratory of Catalysis China National Petroleum Corporation China University of Petroleum Beijing 102249 China

The synthesis of silica with bimodal, disordered mesopores structure, by template-mediated sol-gel processing and subsequent heat-treatment process, was investigated. In the presence of nonionic surfactant Tx-15, the organically modified mesostructured nano-particles were synthesized by co-condensation of organosiloxane （RTES） and tetraethoxysilane （TEOS） in the first step, and then the bimodal porous silica was formed by the removal of the incorporated organic groups using programmed calcination. Here, RTES used was methyltriethoxysilane （MTES）, vinyltriethoxysilane （VTES） and phenyltriethoxysilane （PhTES）, respectively. Organotrialkoxysilane, TEOS and Tx-15 formed MSU-2-1iked assemblies, around which the nano-particles aggregated and cross-linked, considerably influencing the pore size distribution of both primary pores and secondary pores. By changing the type and amount of the organotrialkoxysilane added, a broad variety of silica with a controlled bimodal mesopore distribution could be easily synthesized. Textural and structural properties were determined by X-ray diffraction, high-resolution transmission electron microscopy, N2 adsorption/desorption, and thermogravimetric analysis.

关键词： Organotrialkoxysilane bimodal pore distribution MSU-X

An Effective Asphalt UV Blocking Material Based on Host-Guest Schiff Base/Layered Double Hydroxides

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Chinese Journal of Chemistry 2017年第11期35卷 1701-1705页

作者： Chunhui Xia Rui Gao Kaitao Li Yang Yang yanjun lin Dongpeng Yan State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Beijing Key Laboratory of Energy Conversion and Storage Materials College of Chemistry College of Chemistry Beo'ing Normal University Beijing 100875 China

The development of asphalt-based UV blocking materials is important to extend the alphalt lifespan in road construction. In this work, we put forward that the fabrication of host-guest system can be an effective way to obtain UV blocking materials. Firstly, a new anionic Schiff base, N,N＇bis（salicylidine）-4,4＇-diaminostilbene-2,2＇-disulfonic acid （SDSD）, has been synthesized, which was intercalated into Zn-Al-LDH by anion-exchange method. FT-IR and XRD illustrate the layered organic-inorganic composite, Zn-Al-SDSD-LDH, has been successfully synthesized with high crystallinity. Laser particle size analyzer, SEM and TEM show that particle size distributions of Zn-Al-SDSD-LDH is in the range 100--500 nm. UV-vis absorption spectra show that Zn-Al-SDSD-LDH has better UV absorption than the pristine Zn-Al-LDH and SDSD. Furthermore, the mixture of asphalt and 3 wt% Zn-Al-SDSD-LDH presents enhanced UV blocking property relative to the pristine asphalt after irradiating by UV spray accelerated weathering test. Therefore, this work not only develops a new type of host-guest Zn-Al-SDSD- LDH, but also confirms it can be an effective asphalt UV blocking material for practical application.

关键词： layered double hydroxides UV blocking asphalt Schiffbase

Synthesis of Mg-Al-carbonate layered double hydroxide by an atom-economic reaction

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Particuology 2010年第3期8卷 198-201页

作者： Xiangyu Xu Dianqing Li Jiaqing Song yanjun lin Zhi Lv Min Wei Xue Duan State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

A clean method for preparing layered double hydroxides （LDHs） has been developed, featured by using the hydroxides of two different metals as starting materials by atom-economic reactions. The reactions were carried out under hydrothermal conditions in either a high pressure autoclave or a microwave digester. The compositions, structural parameters and thermal behavior of the resulting LDHs are very similar to those of materials produced by using the separate nucleation and aging steps （SNAS） method. The major advantage of the new method is that no by-product is produced, so that filtration and washing processes are unnecessary. The consequent reduction in water consumption is beneficial to the environment.

关键词： Layered double hydroxides Atom-economic reaction Clean method Mg(OH)2Al(OH)3

Intercalation Assembly and Chemical Product Engineering of Layered Intercalated Functional Materials Based on Efficient Utilization of Magnesium Resources in Salt Lakes

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Acta Geologica Sinica(English Edition) 2014年第S1期88卷 347-349页

作者： lin yanjun NING Bo LI Kaitao WU Qin State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

1 Introduction Magnesium salts are very important by-product of salt lake industry in West *** 200 million cubic meters of waste brine are released to the environment

关键词： layered intercalated functional materials Intercalation assembly chemical product engineering magnesium resources salt lakes

Bidirectional regulation of the brain-gut-microbiota axis following traumatic brain injury

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Neural Regeneration Research 2025年第8期20卷 2153-2168页

作者： Xinyu You lin Niu Jiafeng Fu Shining Ge Jiangwei Shi yanjun Zhang Pengwei Zhuang National Key Laboratory of Chinese Medicine Modernization Tianjin University of Traditional Chinese MedicineTianjinChina Haihe Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjinChina First Teaching Hospital of Tianjin University of Traditional Chinese Medicine TianjinChina National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion TianjinChina

Traumatic brain injury is a prevalent disorder of the central nervous *** addition to primary brain parenchymal damage,the enduring biological consequences of traumatic brain injury pose long-term risks for patients with traumatic brain injury;however,the underlying pathogenesis remains unclear,and effective intervention methods are *** dysfunction is a significant consequence of traumatic brain *** the most densely innervated peripheral tissue in the body,the gut possesses multiple pathways for the establishment of a bidirectional“brain-gut axis”with the central nervous *** gut harbors a vast microbial community,and alterations of the gut niche contribute to the progression of traumatic brain injury and its unfavorable prognosis through neuronal,hormonal,and immune pathways.A comprehensive understanding of microbiota-mediated peripheral neuroimmunomodulation mechanisms is needed to enhance treatment strategies for traumatic brain injury and its associated *** comprehensively reviewed alterations in the gut microecological environment following traumatic brain injury,with a specific focus on the complex biological processes of peripheral nerves,immunity,and microbes triggered by traumatic brain injury,encompassing autonomic dysfunction,neuroendocrine disturbances,peripheral immunosuppression,increased intestinal barrier permeability,compromised responses of sensory nerves to microorganisms,and potential effector nuclei in the central nervous system influenced by gut ***,we reviewed the mechanisms underlying secondary biological injury and the dynamic pathological responses that occur following injury to enhance our current understanding of how peripheral pathways impact the outcome of patients with traumatic brain *** review aimed to propose a conceptual model for future risk assessment of central nervous system-related diseases while elucidating novel insights into the bidirectional effec

关键词： traumatic brain injury brain-gut-microbiome axis gut microbiota neuroimmune immunosuppression host defense vagal afferents bacterial infection dorsal root ganglia nociception neural circuitry