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Chinese Journal of chemical engineering 1998年第1期6卷 90-94页

作者：傅旭庆吕德伟 department of chemical engineering Zhejiang University

1 INTRODUCTIONThe production of secondary metabolites using plant cells has been the subject of much inter-est in recent *** that tremendous research efforts had been made in this topic,notmany products have reached the commercial *** is generally acknowledged that the mainproblem in this field is the lack of basic knowledge of the biosynthetic routes,and the mechanisms found to bring about the production of such secondary *** are,however,some techniques that have beneficial effects on the production and ex-

关键词： Arnebia Euchroma shikonin production two-liquid-phase system

Synthesis and Crystal Structure of 5-Cyclopropyl- 10-(4-fluorophenyl)-7,7-dimethyl-7,8-dihydro-5H- indeno[1,2-b]quinoline-9,11(6H,10H)-dione

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Chinese Journal of Structural Chemistry 2007年第9期26卷 1039-1042页

作者：陈艳屠树江 School of Chemistry and chemical engineering Xuzhou Institute of Technology College department of Chemistry Xuzhou Normal University Key Laboratory of Biotechnology on Medical Plant

The title compound 5-cyclopropyl-10-（4-fluorophenyl）-7,7-dimethyl-7,8-dihydro- 5H-indeno[1,2-b]quinolne-9,11（6H,10H）-dione was obtained by the reaction of 4-fluorobenzal- dehyde, 2H-indene-1,3-dione and 3-（cyclopropylamino）-5,5-dimethylcyclohex-2-enone in the presence of acetic acid under microwave irradiation. Its structure was confirmed by IR and 1H- NMR spectra. The crystal is of monoclinic, space group P21/c with a = 14.138（3）, b = 8.952（2）, c = 17.140（3）A, β = 102.253（3）°, C27H24FNO2, Mr = 413.47, Z = 4, V = 2119.9（8）A^3, Dc = 1.296 g/cm^3, μ（MoKα） = 0.087 mm^-1, F（000） = 872, the final R = 0.0425 and wR = 0.0905 for 2336 observed reflections （I 〉 2σ（I））. X-ray analysis revealed that the pyridine ring adopts a boat conformation and the six-membered ring fused with it assumes a twist boat conformation.

关键词： aldehydes 1,3-indanedione enaminones synthesis microwave irradiation crystal structure

A tribo-chemical view on astringency of plant-based food substances

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Friction 2024年第7期12卷 1392-1407页

作者： Samuel S.GAMANIEL Paloma S.DUEÑAS ROBLES Hans TROMP Els H.A.de HOOG Sissi de BEER Emile van der HEIDE Laboratory for Surface Technology and Tribology Faculty of Engineering TechnologyUniversity of TwenteEnschede 7522 LWthe Netherlands NIZO Food Research B.V. Ede6710 BAthe Netherlands department of Molecules and Materials MESA+Institute for Nanotechnology University of TwenteEnschede 7500 AEthe Netherlands

Consumption of plant-based food products having high composition of polyphenols leads to the sensation of *** sliding oral surfaces,friction is an essential property during the oral perception of roughness and dryness which are attributes associated with *** factors including the chemical composition of interacting layers,structure and operation of interfaces have an effect on the astringency development *** manner of interactions occurring at oral interfaces suggest there is a system dependence of astringency and highlights the importance of adopting a tribosystems *** measurement techniques have shown an existing relationship between salivary protein-polyphenol interaction and an astringent ***,the tribo-chemistry involved in this multifaceted sensation remains largely unexplored in a comprehensive *** this review the underlying tribo-chemical processes useful in understanding the mechanism of astringency are highlighted and discussed considering current techniques employed to investigate astringency *** of lubrication on oral surfaces owing to the tribo-chemical interactions involving saliva and astringent plant proteins requires subsequent deformations of oral tissues which are significant enough to induce strains at mechanoreceptor locations,leading to the sensation of *** is proposed that micro-scale contact modelling on the interaction of food particles/aggregates,boundary layers and oral surfaces shows potential in addressing the knowledge gap between tribo-chemical measurement techniques and panel tests,making it possible to attain a predictor for astringency.

关键词： oral lubrication astringency tribo-chemistry tribology

A nano-delivery system expands the insecticidal target of thiamethoxam to include a devastating pest,the fall armyworm

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Insect Science 2023年第3期30卷 803-815页

作者： Qin-Hong Jiang Ting Li Yan Liu Zi-Yi Zhou Yang Yang Ying Wei Mei-Zhen Yin Jie Shen Shuo Yan department of plant Biosecurity and MARA Key Laboratory of Surveillance and Management for plant Quarantine Pests College of Plant ProtectionChina Agricultural UniversityBejingChina State Key Laboratory of chemical Resource engineering Bejing Lab of Biomedical MaterialsBejing University of Chemical TechnologyBeijingChina

Nano-delivery systems have been applied to deliver various synthetic/botanical pesticides to increase the efficiency of pesticide use and reduce the volumes of pesticides *** studies have supported the hypothesis that the nanocarriers can help expand the insecticidal target of pesticides to include non-target ***,the potential mechanism underlying this interesting phenomenon remains ***,a widely applied star polycation(SPc)nanocarrier was synthesized to construct a thiamethoxam(TMX)nano-delivery *** SPc-based delivery system could promote the translocation of exogenous substances across the membrane of Sf9 cells,increase the cytotoxicity of TMX against Sf9 cells by nearly 20%,and expand the insecticidal target of TMX to include Spodoptera frugiperda(the fall armyworm),with a 27.5%mortality increase at a concentration of 0.25 mg/***,the RNA-seq analysis demonstrated that the SPc could upregulate various transport-related genes,such as Rab,SORT1,CYTH,and PIKfive,for the enhanced cellular uptake of ***,enhanced cell death in larvae treated with the TMX-SPc complex was observed through changes in the expression levels of death-related genes,such as Casp7,BIRC5,MSK1,and *** SPc-based nano-delivery system improved the cellular uptake of TMX and expanded its insecticidal target by adjusting the expression levels of death-related *** current study mainly identified the transport and cell death genes related to nanocarrier-based insecticidal target expansion,which is beneficial for understanding the bioactivity enhancement of the nano-delivery system.

关键词： insecticides nanotechnology nanomaterials thiamethoxam

Five quinolizidine alkaloids with anti-tobacco mosaic virus activities from two species of Sophora

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Chinese chemical Letters 2024年第6期35卷 380-384页

作者： Ji Zhang Tong Zhang Qiao An Peng Zhang Cai-Yan Tian Chun-Mao Yuan Ping Yi Zhan-Xing Hu Xiao-Jiang Hao State Key Laboratory of Functions and Applications of Medicinal plants Guizhou Medical UniversityGuiyang 550014China Natural Products Research Center of Guizhou Province Guiyang 550014China School of Pharmaceutical Sciences Guizhou Medical UniversityGuiyang 550025China School of Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China State Key Laboratory of Phytochemistry and plant Resources in West China Kunming Institute of BotanyChinese Academy of ScienceKunming 650201China Research Unit of chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical SciencesKunming 650201China

Three novel matrine-type alkaloids(1-3)and two unprecedented aloperine-type alkaloids(4 and 5)were isolated from the root of Sophora tonkinensis and the seeds of Sophora alopecuroides ***,compound 1 possessed an unprecedented 6/5/6 tricyclic skeleton,while compounds 2 and 3 characterized by rare 6/6/5/6 tetracyclic system and 6/6/6/6/6 pentacyclic system ***,compound 4 possessed an unprecedented 6/7/6/6 tetracyclic core,and compound 5 characterized by rare 6/6/6/6tetracyclic *** structures were elucidated by comprehensive spectroscopic data analysis and electronic circular dichroism(ECD)*** tests indicated that compound 5 displayed significant anti-tobacco mosaic virus(TMV)activity compared with the positive control ningnanmycin.

关键词： Matrine-type alkaloids Aloperine-type alkaloids Sophora tonkinensis Sophora alopecuroides Anti-tobacco mosaic virus

Spatiotemporal variation and evaluation of agriculture green development: a case study of Hainan Province, China

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Frontiers of Agricultural Science and engineering 2024年第1期11卷 83-99页

作者： Tianxiang YU Jichen ZHOU Lin MA Fusuo ZHANG Zed RENGEL William JDAVIES Jianbo SHEN department of plant Nutrition College of Resources and Environmental SciencesCenter for ResourcesEnvironment and Food SecurityKey Laboratory of Plant-Soil interactionsMOENational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China Sanya Institute of China Agricultural University Sanya 572025China Soil Physics and Land Management Group Wageningen UniversityP.O.Box 476700 AA Wageningenthe Netherlands Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetic and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China Soil Science and plant Nutrition UWA School of Agriculture and EnvironmentThe University of Western AustraliaPerth WA 6009Australia Institute for Adriatic Crops and Karst Reclamation 21000 SplitCroatia Lancaster Environment Centre University of LancasterLancaster LA14YQUK

The realization of green and sustainable development of agriculture is the common pursuit all over the world. Agriculture green development(AGD)program has been proposed as a sustainable development strategy in China,but insufficient is known about the quantitative evaluation of spatiotemporal variation in AGD at the regional scale. This study aimed to assess spatiotemporal patterns in AGD at the county/city-based regional level. For this purpose, a systematic index evaluation system was developed to assess the performance of socioeconomic, food production and environmental components in a key economic region(Hainan Province) of China. Hainan improved its AGD index(representing the overall performance toward achieving AGD) from 38.8 in 1988 to 40.9 in 2019. The socioeconomic development and agricultural productivity have improved with time;environmental quality declined due to overuse of chemicals from 1988 to 2013, but steadily improved after 2013, indicating positive effects of reducing chemical input. There was a higher AGD index in the coastal vs. central regions and the southern vs. northern regions. Scenarios featuring improved nutrient management or optimized diet structure and reduced waste improved economic benefits and social productivity while concurrently reducing environmental degradation. These results provide new insights for the future development of green and sustainable agriculture and formulation of agricultural policies in Hainan Province of China and even other developing countries that are facing or will soon face similar challenges.

关键词： Agriculture environmental impact green and sustainable development Hainan Province index evaluation system

Carbon dioxide induced degradation of diethanolamine during absorption and desorption processes

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Chinese Journal of chemical engineering 2018年第2期26卷 293-302页

作者： Md.Sakinul Islam Kotaiah Naik Dhanavath Nhol Kao Pradipto K.Bhattacharjee Brahim Si Ali Rozita Yusoff department of chemical engineering School of EngineeringRMIT UniversityMelbourneVIC 3001Australia department of chemical engineering Faculty of EngineeringUniversity of Malaya50603 Kuala LumpurMalaysia

Alkanolamines are widely used in the purification of the sourgas sweetening process. During the sour gas absorption process, CO_2 significantly degrades the amine solvent and creates enormous problems for plant operation. In this work, CO_2 induced degradation of aqueous diethanolamine(DEA) solution was conducted in a 1.25 L jacketed glass reactor that functioned as an absorber and stripper at atmospheric conditions. Pure CO_2 was bubbled through the reactor until the solution became saturated. In this study, the concentrations of DEA used were in the range of concentrations between 2 mol·L^(-1) and 4 mol·L^(-1). In the degradation experiment, six generic cycles were conducted for each run. Each cycle was configured with the absorption and desorption of carbon dioxide at 55 ℃ and 100 ℃, respectively. Samples were collected after a predetermined experimental time and analyzed by ion chromatography(IC) to identify unknown ionic degradation products(DGPs). In the IC analysis, three different columns were used for anion, cation and ion exclusion systems, which are Metrosep A Supp 5150/4.0, Metrosep C Supp 4 150/4.0 and Metrosep Organic Acids, respectively. The major identified DGPs of D01 DEA2 M, D02 DEA3 M, and D03 DEA4 M are nitrite, acetate and ammonium. Phosphate product was found in the degraded amine samples which might be due to the contamination of water or chromatographic system.

关键词： Degradation Diethanolamine Absorption Stripping Gas sweetening process

Heterogeneity analysis of gas-solid flow hydrodynamics in a pilot-scale fluidized bed reactor

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Chinese Journal of chemical engineering 2022年第10期50卷 117-129页

作者： Jiawei Liao Litao Zhu Zhenghong Luo department of chemical engineering School of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Mesoscale drag model is of crucial significance for the reliability and accuracy in coarse-grid EulerianEulerian two-fluid model(TFM)simulations of gas-solid flow hydrodynamics in fluidized bed *** numerous mesoscale drag models have been reported in the literature,a systematic comparison of their prediction capability from the perspective of heterogeneity analysis is still *** this study,in order to investigate the effect of several typical drag models on the hydrodynamic behaviors,the nonuniformity analysis and the sensitivity to material properties,extensive coarse-grid TFM simulations of a bubbling pilot-scale fluidized bed reactor are carried *** results demonstrate that the mesoscale drag models outperform the empirical drag model in terms of nonuniformity due to the consideration of the influence of the mesoscale structures on the drag force in the bubbling ***,the results reveal that our previously developed three-marker gradient-based drag model considering the solid concentration gradient exhibits satisfactory performance in predicting the bubbling flow ***,the material-property-dependent drag model considering the explicit effect of material properties on drag corrections is most sensitive to the particle *** work provides guideline for possible future improvements of mesoscale models to simulate gas-solid flow more accurately and universally.

关键词： Fluidized bedreactor Bubbling gas–solidflows Mesoscale dragmodels Coarse-grid TFMsimulations Heterogeneity analysis

Determination of particle size distribution by multi-scale analysis of acoustic emission signals in gas-solid fluidized bed

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2011年第4期12卷 260-267页

作者： Cong-jing REN Jing-dai WANG Di SONG Bin-bo JIANG Zu-wei LIAO Yong-rong YANG State Key Laboratory of chemical engineering Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 China

Particle size distribution(PSD) is an important parameter in the process of fluidization,and it always plays a crucial role in a gas-solid fluidized system.A PSD model for on-line PSD determination based on acoustic emission(AE) measurement was developed according to the mechanism of particle collision with the inner wall of the cylinder and multi-scale wavelet decomposition *** PSD model illuminates the quantitative relationship between the energy percentage of AE signals for different scales and the PSD,which indicates the feasibility of the application of the PSD *** were undertaken both in lab and plant gas-solid fluidized setup with polyethylene particles,and the parameters of the PSD model were calibrated and *** experimental conditions and results proved that the PSD model was suitable for on-line measurement and was sufficiently sensible and *** agglomeration,the PSD model also showed exact serviceability on detecting the onset of agglomeration by abnormal PSD,and the result agreed with that from the radiation ***,AE measurement was found to be a reliable and credible means for understanding the PSD information that affects the behavior of a system,which can provide valuable guidance for practical applications.

关键词： Particle size distribution(PSD) Acoustic emission(AE) Fluidized bed Multi-scale Agglomeration

An AIE Star Polymer with Enhanced Co-Delivery of Drug and Gene for Synergistic Pest Control

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Chinese Journal of Chemistry 2023年第20期41卷 2671-2678页

作者： Bingcheng Zhou Qinhong Jiang Jie Li Shuo Yan Jie Shen Lianying Liu Meizhen Yin State Key Laboratory of chemical Resource engineering Beijing Lab of Biomedical MaterialsBeijing University of Chemical TechnologyBeijing100029 China department of plant Biosecurity and MARA Key Laboratory of Surveillance and Management for plant Quarantine Pests College of Plant ProtectionChina Agricultural UniversityBeijing100193 China

Pesticides,as the most common means of pest managements,have caused a series of problems such as pest resistance and environmental ***-induced emission(AIE)polymers exhibit great potential in biological applications because their fluorescent intensities significantly enhance in the aggregated *** this paper,an AIE star polymer including a tetraphenyl ethylene(TPE)core and poly(2-(dimethylamino)ethyl methacrylate)arms is designed and further developed as a multi-functional nanocarrier for agricultural pest *** nanocarrier shows high water solubility,good size stability and AIE imaging ***,the twisted AIE core and positively charged polymer arms make the nanocarrier efficiently co-load dinotefuran(DIN)and dsRNA via hydrogen bonds and electrostatic interactions,*** AIE star polymer displays low toxicity and high fluorescence *** a result,the nanocarrier co-loading with DIN and dsRNA exhibits a highly synergistic insecticidal effect with higher pest mortality compared to the separate delivery of DIN and *** study develops the AIE star polymer to improve the efficiency of co-delivery of drug and dsRNA and proposes a new strategy toward efficient and synergistic pest control.

关键词： Pest control Nano-delivery system Drug nanocarrier Functional polymers Aggregation-induced emission