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Assessing the kinetic model of hydro-distillation and chemical composition ofAquilaria malaccensis leaves essential oil

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Chinese Journal of Chemical Engineering 2017年第2期25卷 216-222页

作者： Mahtab Samadi Zurina Zainal Abidin Robiah Yunus dayang radiah awang biak Hiroyuki Yoshida Eng Hai Lok Department of Chemical and Environmental Engineering Faculty of EngineeringUniversity Putra MalaysiaserdangSelangorDaml Ehsan 43400Malaysia Aerospace Manufacturing Research Centre(AMRC) Level 7Tower BlockFaculty of EngineeringUniversity Putra Malaysia43400 5erdang SelangorMalaysia Forest Research Institute Malaysia 52109 Kepong5elangorDarul EhsanMalaysia

This study aimed to model the kinetic of hydro-distillation of Aquilaria malaccensis leaves oil in order to understand and optimize the extraction process. In addition, this study, for the first time, aimed to identify the chemical compositions of the A. rnalaccensis leave-oil. By assessing both first-order kinetic model and the model of simultaneous washing and diffusion, the result indicated that the model of simultaneous washing and diffusion better describes the hydro-distillation mechanism of the essential oil from A. rnalaccensis leaves. The optimum time, solid to liquid ratio, and the heating power for extracting the highest amount of essential oil were found to be around 3 h, 1：10 （g. ml-1）, and 300 W respectively. Yellow essential oil with a strong smell and a yield of 0.05 v/w was extracted by hydro-distillation Clevenger apparatus. Chemical compounds of the essential oil were analyzed using gas chromatography-mass spectroscopy （GC/MS）, which resulted in identification of 42 compounds that constitute 93% of essential oil. Among the identified components, Pentadecanal （32.082%）, 9-Octadecenal, （Z）（15.894%）, and Tetradecanal （6.927%） were the major compounds. Considering the fact that all the identified major components possess pesticidal properties, A. malaccensis leaves can be regarded as a promising natural source for producing pesticides.

关键词： Aquilaria malaccensisEssential oilHydro-distillationOptimizationKinetic modeling

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Hydrophobic modification of polysaccharides and the construction and properties of their micelles:a review of applications in the field of biomedicine

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Science China Chemistry 2024年第6期67卷 1881-1903页

作者： dayang Wang Xiaohua Li Huanchen Yao Xin Liu Yan Gao Hailin Cong Bing Yu Youqing Shen College of Chemistry and Chemical Engineering College of Life SciencesCollege of Materials Science and EngineeringInstitute of Biomedical Materials and EngineeringQingdao UniversityQingdao266071China State Key Laboratory of Bio-Fibers and Eco-Textiles Qingdao UniversityQingdao266071China School of Materials Science and Engineering Shandong University of TechnologyZibo255000China Key Laboratory of Biomass Chemical Engineering of Ministry of Education Center for Bionanoengineeringand Department of Chemical and Biological EngineeringZhejiang UniversityHangzhou310027China

Nanomedicine delivery technology plays an important role in modern medicine and has shown good therapeutic effects in scientific *** have the characteristics of wide sources,excellent biocompatibility,and *** addition,there are multifunctional groups on the main chain of polysaccharides,which can be surface-modified or functionalized to have targeting ability through specific sugar *** polysaccharide micelles with good biocompatibility,degradability,high safety,easy structural modification,and special core-shell structure are regarded as ideal carriers for ***,this review is focused on the hydrophobic modification designs of polysaccharides,the preparation methods and characteristics of micelles,and the applications of amphiphilic polysaccharide micelles in the field of *** is expected to provide some ideas and inspiration for the design of polysaccharide drug carriers.

关键词： polysaccharide hydrophobic modification micelle drug delivery biomedicine

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Peat properties of a tropical forest reserve adjacent to a fire-break canal

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Journal of Forestry Research 2024年第1期35卷 155-167页

作者： dayang Nur Sakinah Musa Mohd Zahirasri Mohd Tohir Xinyan Huang Luqman Chuah Abdullah Mohamad Syazaruddin Md Said Muhammad Firdaus Sulaiman Safety Engineering Interest Group(SEIG) Department of Chemical and Environmental EngineeringFaculty of EngineeringUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia International Tropical Forestry Programme Faculty of Tropical ForestryUniversiti Malaysia SabahSabahMalaysia Department of Land Management Faculty of AgricultureUniversiti Putra MalaysiaSelangorMalaysia Research Centre for Fire Safety Engineering Department of Building Environment and Energy EngineeringThe Hong Kong Polytechnic UniversityHong KongPeople’s Republic of China

Tropical peat comprises decomposed dead plant material and acts like a sponge to absorb water,making it fully ***,drought periods dry it readily and increases its vulnerability to *** fires emit greenhouse gases and particles contributing to haze,and prevention by constructing fire-break canals to reduce fire spread into forest reserves is *** paper aims to determine peat physical and chemical properties near a fire-break canal at different fire frequency *** sampling was conducted at two forest reserves in Malaysia which represent low fire frequency and high fire frequency *** results show that peat properties were not affected by the construction of a fire-break canal,however lignin and cellulose content increased significantly from the distance of the canal in both *** study concluded that fire frequency did not significantly influence peat properties except for *** higher fibre content in the high frequency area did not influence moisture content nor the ability to regain ***,fire frequency might contribute differently to changes in physical and chemical properties,hence management efforts to construct fire-break canals and restoration efforts should protect peatlands from further *** findings will benefit future management and planning for forest reserves.

关键词： Peat fire Peat properties Fire-break canals Forest reserves

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全氟-2,2-二甲基-1,3-二氧环戊烯-四氟乙烯共聚物平均分子量、分子量分布和流变特性

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高校化学工程学报 2024年第1期38卷 128-134页

作者：郑威余大洋包永忠浙江大学化学工程与生物工程学院化学工程联合国家重点实验室(浙江大学)浙江杭州310058 浙江大学衢州研究院浙江衢州324000

全氟-2,2-二甲基-1,3-二氧环戊烯-四氟乙烯(PDD-TFE)共聚物是高性能含氟聚合物,开展PDD-TFE共聚物平均分子量(MW)、分子量分布(MWD)和流变特性研究对拓展其加工应用有重要意义。鉴于溶液法测定PDD-TFE共聚物MW及MWD存在难度,建立了由动... 详细信息

全氟-2,2-二甲基-1,3-二氧环戊烯-四氟乙烯(PDD-TFE)共聚物是高性能含氟聚合物,开展PDD-TFE共聚物平均分子量(MW)、分子量分布(MWD)和流变特性研究对拓展其加工应用有重要意义。鉴于溶液法测定PDD-TFE共聚物MW及MWD存在难度,建立了由动态流变法和动态黏弹法获得PDD-TFE共聚物MW及MWD的改进方法。根据Fox方程、共聚物结构和性能参数得到了PDD-TFE共聚物的零切黏度与MW之间的关系;通过Carreau-Yasuda方程拟合PDD-TFE共聚物的复数黏度与频率之间的关系,得到了零切黏度。在实验测定PDD-TFE共聚物的储能模量与频率关系基础上,应用动态黏弹法得到其MW及MWD,并进一步研究了220℃时PDD-TFE共聚物的MW及MWD对共聚物熔体流变特性的影响,发现共聚物的MWD越宽,共聚物熔体的“剪切变稀”行为越明显;随着共聚物MW增大,共聚物熔体的非牛顿性越强。

关键词：全氟-2,2-二甲基-1,3-二氧环戊烯-四氟乙烯共聚物平均分子量流变特性黏度

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Solvent and guest-binding-controlled chiroptical inversion of molecular devices based on pseudo[1]catenane-type pillar[5]arene derivatives

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Chinese Chemical Letters 2024年第1期35卷 280-284页

作者： Yongjun Lv Chao Xiao Jingyu Ma dayang Zhou Wanhua Wu Cheng Yang College of Chemical Engineering Sichuan University of Science&EngineeringZigong 643000China College of Chemistry Sichuan UniversityChengdu 610064China Zhejiang NHU Pharmeceutical Co. Ltd.Shaoxing 312000China Comprehensive Analysis Center ISIROsaka UniversityOsaka 567-0047Japan

Four pillar[5]arene-based bicyclic compounds,so-called molecular universal joint(MUJ),were synthesized by incorporating a bisamide ring containing N,O,or S-heteroatom groups,which served as stimuli-responsive chiroptical molecular *** structure of MUJ was confirmed by 1H NMR spectra and single-crystal X-ray diffraction analysis,and their planar-chiral enantiomers were successfully *** inversion behaviors from in to out configurations triggered by temperature,solvent,and guest complexation were investigated by circular dichroism *** inversion could be realized in the presence of adiponitrile in certain solvents due to the solvation effects on the side ring and the threading of the guest into the pillar[5]arene ***,the stronger self-included interactions between the cavity and the inside ring of certain MUJs led to inhibition of the switching.

关键词： Pillararene N,O,S-containg ring Bicycles Solvation Chirality inversion

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Versatile chiroptical induction/manipulation through specific solvation of ion pairs by alcohols

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Science China Chemistry 2024年

作者： Chunhong Liu Xin Chen Yanling Shen Ting Zhao dayang Zhou Kun Li Jiecheng Ji Wanhua Wu Xuemei Pu Cheng Yang Key Laboratory of Green Chemistry & Technology of Ministry of Education Sichuan University Comprehensive Analysis Center ISIR Osaka University

While extensive research has explored manipulating supramolecular chirality through internal and external factors, the specific solvation effect remains uncharted territory. This study synthesized ortho-functionalized pillar[5]arene（P[5]） derivatives Mn and Dn via thiol-Michael addition, characterizing them through spectroscopic and X-ray single-crystal analyses. Mn and Dn interacted with chiral amines, yielding significant circular dichroism（CD） responses. Intriguingly, the chiral induction exhibited pronounced specific solvation effects, where achiral alcohols either enhanced, attenuated, or reversed CD signals. Testing over40 alcohols revealed correlations between the specific solvation effects and alcohol polarity and acidity. Molecular dynamics simulations unveiled that the alcohol interacted distinctly through hydrogen bonding, with one ion pair bonding up to four alcohol molecules. The Rp-and Sp-preference of the P[5] core could be altered by the number of bonded alcohols. This work uncovers the critical role of alcohol-specific solvation in ion pair-involved chiral assembly, pertinent for asymmetric ion-pairing catalysis and the use of alcohol additives in organic solvents.

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Biochar induced trade-offs and synergies between ecosystem services and crop productivity

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Journal of Integrative Agriculture 2024年第11期23卷 3882-3895页

作者： Jinxia Wang Qiu Huang Kai Peng dayang Yang Guozhen Wei Yunfei Ren Yixuan Wang Xiukang Wang Nangia Vinay Shikun Sun Yanming Yang Fei Mo College of Agronomy Northwest A&F University Agricultural and Animal Husbandry Technology Extension Center College of Life Sciences Yan'an University International Center for Agricultural Research in the Dry Areas (ICARDA) College of Water Resources and Architectural Engineering Northwest A&F University College of Agronomy Inner Mongolia Agricultural University

Biochar amendment offers a chance for sustainable agriculture. However, the effectiveness of biochar relies on its physical and chemical properties, which are heavily affected by biochar production conditions and management practices. Therefore, substantial uncertainties regarding the use of biochar exist in agricultural systems *** study provides the first quantitative evaluation of the impacts of biochar characteristics and management practices on key ecosystem services by performing a second-order meta-analysis based on 34,628 paired observations in biochar-amended and unamended systems. Overall, biochar enhances phytotoxicity alleviation,physiology regulation, soil remediation and carbon sequestration, and microbial functional gene ***, some prominent trade-offs exist between crop productivity and ecosystem service deliveries including for nutrient cycling, microbial function, climate change mitigation, and the soil microbial community. The adoption of low C:N biochar produced at high pyrolysis temperatures from sewage sludge-derived feedstock, in combination with a moderate application rate and inorganic fertilizer input, shows potential for achieving synergistic promotion of crop productivity and ecosystem services. These outcomes highlight the need for judicious implementation of biochar-based solutions to site-specific soil constraints. The quantified synergy and tradeoff relationships will aid the establishment of a sustainable biochar development framework that strengthens necessary ecosystem services commensurate with food security assurance.

关键词： biochar soil remediation phytotoxicity alleviation carbon sequestration productivity

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碘转移本体聚合制备PS-b-PBA-b-PS共聚物:聚合动力学、结构和性能

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高校化学工程学报 2024年第3期38卷 432-439页

作者：章璐鑫常兆恒余大洋包永忠浙江大学化学工程与生物工程学院化学工程国家重点实验室(浙江大学)浙江杭州310058 浙江大学衢州研究院浙江衢州324000

以碘仿为链转移剂、偶氮类化合物为引发剂,通过碘转移本体聚合合成碘封端聚丙烯酸丁酯(I-PBA-I),并以其调节苯乙烯扩链聚合,制得聚苯乙烯-b-聚丙烯酸丁酯-b-聚苯乙烯(PS-b-PBA-b-PS)共聚物,研究了聚合动力学、共聚物结构和性能。发现丙... 详细信息

以碘仿为链转移剂、偶氮类化合物为引发剂,通过碘转移本体聚合合成碘封端聚丙烯酸丁酯(I-PBA-I),并以其调节苯乙烯扩链聚合,制得聚苯乙烯-b-聚丙烯酸丁酯-b-聚苯乙烯(PS-b-PBA-b-PS)共聚物,研究了聚合动力学、共聚物结构和性能。发现丙烯酸丁酯均聚和苯乙烯扩链聚合均符合活性自由基聚合特征,反应初始BA与CHI3物质的量比n_(BA,0)/n_(CHI3,0)从100/1增至1 000/1时,I-PBA-I数均分子量由15 000增大到134 500;以数均分子量为28 400的I-PBA-I为大分子链转移剂,反应初始BA与St物质的量比n_(BA,0)/n_(St,0)为1/1、1/2、1/3和1/4时扩链得到数均分子量分别为46 000、69 000、97 500、127 000的PS-b-PBA-b-PS共聚物;嵌段共聚物微相分离,在增韧的同时保持一定的透光率,PS与PBA物质的量比n_(PS)/n_(PBA)为3.85/1的嵌段共聚物抗冲强度与商品化阴离子活性聚合苯乙烯-丁二烯嵌段共聚树脂相当。

关键词：聚苯乙烯聚丙烯酸丁酯碘转移聚合聚合动力学嵌段共聚物

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可恢复功能复合结构体系基于层间位移角谱的抗震设计方法

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建筑结构学报 2024年第10期45卷 67-77页

作者：武大洋赵斌杨国涛邢丽丽青岛理工大学土木工程学院同济大学结构防灾减灾工程系

针对可恢复功能结构的抗震韧性设计，需解决震后功能恢复需求与抗震韧性能力之间的量化问题。为此，以层间位移角为主要设计指标，采用拓展弯剪双梁模型初步建立了可恢复功能复合结构体系基于层间位移角谱的抗震设计方法。在设防和罕遇... 详细信息

针对可恢复功能结构的抗震韧性设计，需解决震后功能恢复需求与抗震韧性能力之间的量化问题。为此，以层间位移角为主要设计指标，采用拓展弯剪双梁模型初步建立了可恢复功能复合结构体系基于层间位移角谱的抗震设计方法。在设防和罕遇两水准地震作用下，采用弹性设计计算和弹塑性响应估算的两阶段设计框架和流程。弹性阶段采用由层间位移角谱建立的震后功能恢复需求与抗震韧性能力之间的量化关系完成参数计算，弹塑性阶段进行响应估算完成位移与层间位移角的验算。基于概率考虑残余位移的性能评估表明：据此方法设计的复合体系可以实现两水准地震作用下的设计目标；相比无控结构，复合体系不仅在两水准地震作用下的层间位移角均值降幅达到50%和60%,而且在增量地震作用下残余变形和损伤分布均得到有效控制。

关键词：可恢复功能结构复合结构体系抗震设计方法层间位移角谱分布参数模型性能评估

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覆岩隔离注浆充填技术实践与研究展望

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中国煤炭 2024年第6期50卷 74-80页

作者：许家林轩大洋李建煤炭精细勘探与智能开发全国重点实验室江苏省徐州市221116 中国矿业大学矿业工程学院江苏省徐州市221116

煤层开采后覆岩关键层失去下部支撑,在地层压力作用下断裂沉降是导致一系列采动损害与环境问题的根源,通过充填阻止关键层破断是减少环境损害的源头绿色开采技术。目前我国煤矿充填开采技术得到长足发展,但井下充填采煤存在效率相对较... 详细信息

煤层开采后覆岩关键层失去下部支撑,在地层压力作用下断裂沉降是导致一系列采动损害与环境问题的根源,通过充填阻止关键层破断是减少环境损害的源头绿色开采技术。目前我国煤矿充填开采技术得到长足发展,但井下充填采煤存在效率相对较低、成本较高等问题,限制了其推广应用。而创新研发的覆岩隔离注浆充填技术,建立了地面钻孔“一注式减损”高效绿色开采新模式,突破了井下充填效率低的技术瓶颈。覆岩隔离注浆充填是基于采动覆岩卸荷膨胀累积效应对离层产生抑制作用,通过地面钻孔向关键层下进行高压注浆的充填,产生“压下托上”作用,将关键层下方碎胀岩体压实形成支撑体,在采空区形成压实承载结构,阻止关键层断裂。该技术解决了离层注浆充填量少、减沉率低的技术难题,可用于综采、综放工作面,以及单一煤层与多煤层开采;目前该技术已在全国推广应用,解决了东部矿区建筑物压煤开采难题,并在矸石减排、“减震防冲”“减漏保水”等方面开展了工程试验与实践。介绍了“双碳”背景下,针对煤矿充填材料不足问题,进一步研发“煤基固废+CO 2”覆岩隔离注浆充填绿色开采新技术构想,该技术可取得减沉、减漏、减震、减排、减碳等“一注五减”效果,实现煤炭资源的绿色开采与低碳利用。

关键词：岩层移动覆岩卸荷膨胀累积效应关键层覆岩隔离注浆充填绿色开采

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