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Dispersant-assisted dynamic microwave extraction of triazine herbicides from rice

ANALYTICAL METHODS 2016年第18期8卷 3788-3794页

作者： li, Dan Zhang, Ziwei li, Na Wang, Kun Zang, Shuang Jiang, Jia Yu, Aimin Zhang, Hanqi li, xuwen Jilin Univ Coll Chem Qianjin St 2699 Changchun 130012 Peoples R China Harbin Inst Technol Weihai Sch Marine Sci & Technol Weihai 264209 Peoples R China

A rapid and effective sample pretreatment method, dispersant-assisted dynamic microwave extraction, was first applied to the extraction of six triazine herbicides from rice. The dynamic microwave extraction was coupled with matrix solid-phase dispersion (MSPD). The dispersant in MSPD was used to disperse the sample and adsorb impurities. Microwave irradiation was used to promote the transfer of the analyte and accelerate the extraction. The extraction and clean-up were performed simultaneously. The effects of experimental parameters, including the solvent type, volume of the extraction solvent, microwave power, type of dispersant, mass ratio of dispersant to rice, and flow rate of the extraction solvent, on the recoveries of the analytes were investigated. The limits of detection for the analytes ranged from 0.62 to 1.79 mu g kg(-1). The recoveries of the triazine herbicides in spiked rice samples were in the range of 84.3-101%, and the relative standard deviations were lower than 6.2%.

关键词： Microwave irradiation

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The Optimization of the Technologic Parameter in Strong Cooling with Single-tube on the A356 Alloy

The Optimization of the Technologic Parameter in Strong Cool...

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International Conference on Advances in Materials and Manufacturing Processes

作者： Zheng, Zhiqiang Xiong, Xingen Chen, Keming lin, Bojun li, xuwen Nanchang Univ Nanchang 330031 Peoples R China

ISBN: (纸本)9780878492039

The tube spread around strong cooling technology is new technology of the making semisolid slurry and semisolid billet in Semi-Solid Processing. The technologic parameter of its on the A356 Alloy is researched in the article. It is showed by the result of the experimentation: that the fine and form verge on rotundity crystal grain is made at 180L/h and at 640-650 degrees C. It has met all the conditions in the semi-solid processing on semisolid billet. Semi-solid forming technology has been called the "new metal processing technology in the 21st century", which in foreign countries has certain industrial applications. In 1996 in the United States the sales of semi-solid casting was up to 1 billion dollars. But the industrial application in China is almost empty, one of the most important reasons is: the preparation of slurry or billet is too complicated or cost of production is too high, so that semi-solid forming technology in China has suffered serious setbacks on the road of industrialization. According to this situation, we have done a little attempts on manufacturing slurry and billet of semi-solid forming and have developed a new technology of spread around strong cooling whose intellectual property rights belong to us, equipment production is simple and the process is easy to control and the semi-solid slurry is east to prepare continuously. It will be discussed in this paper that process parameters of the single-tube strong cooling impacts on the microstructure of semi-solid

关键词： strong cooling with single-tube semi-solid A356 alloy technologic parameter microstructure

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The biologically and ecologically important natural products from the Chinese sea hare Bursatella leachii:structures,stereochemistry and beyond

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Chinese Journal of Natural Medicines 2024年第11期22卷 1030-1039页

作者： ZHANG Xinyuan SU Mingzhi ZHU Mingxin CHEN Sha GAO Zhen GUO Yuewei li xuwen School of Chinese Materia Medica Nanjing University of Chinese MedicineNanjing 210023China State Key Laboratory of Chemical Biology Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Shandong Laboratory of Yantai Drug Discovery Bohai Rim Advanced Research Institute for Drug DiscoveryYantai 264117China

A novel amide alkaloid,bursatamide A(1),featuring an unprecedented propyl-hexahydronaphthalene carbon frame-work,was isolated from the infrequently studied sea hare Bursatella leachi,alongside a new 3-phenoxypropanenitrile alkaloid,bursatellin B(2),and twelve known *** structures of 1 and 2 were elucidated through comprehensive spectroscopic data analyses,while their relative and absolute configurations(ACs)were established through total synthesis and a series of quantum chem-ical calculations,including calculated electronic circular dichroism(ECD)spectra,optical rotatory dispersion(ORD)methods,and DP4^(+) probability *** A(1)demonstrated inhibitory effects against the human pathogenic bacteria listeria monocyt-ogenes and Vibrio ***-bursatellin B(21),a diastereoisomer of 2,exhibited notable antibacterial activity against the fish pathogenic bacterium Streptococcus parauberis FP KSP28,with an MIC90 value of 0.0472 μg·mL^(-1).

关键词： Bursatella leachii Marine natural product Alkaloid Sea hare Antibacterial activity

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lignan Extraction from the Roots of Sinopodophyllum emodi Wall by Matrix Solid-Phase Dispersion

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CHROMATOGRAPHIA 2010年第7-8期72卷 713-717页

作者： Shi, Xiaolei li, xuwen liu, Jingbo Zhou, Hongyu Zhang, Hanqi Jin, Yongri Jilin Univ Coll Chem Changchun 130012 Jinlin Province Peoples R China Jilin Univ Coll Quartermaster Technol Changchun 130012 Jinlin Province Peoples R China

A fast and simple procedure based on matrix solid-phase dispersion was carried out for the extraction of three kinds of lignans, including podophyllotoxin, 4'-demethylpodophyllotoxin and podophyllotoxin glucoside, from the dried roots of Sinopodophyllum emodi Wall. After extraction, the lignans were determined by LC. The main experimental parameters, including type of dispersant, type of clean-up absorbent and type and volume of elution solvent, were examined and optimized. Compared with reflux extraction, the proposed method is simpler, faster and more efficient.

关键词： Column liquid chromatography Matrix solid-phase dispersion lignans Scanning electron micrograph

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Software design of hardware-in-the-loop simulation system based on rapidio 8

Software design of hardware-in-the-loop simulation system ba...

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8th International Conference on Computing and Pattern Recognition, ICCPR 2019

作者： li, xuwen Hu, Jiashun Wu, Xuegang Wu, Qiang Beijing University of Technology College of Life Science and Bioengineering Beijing China

ISBN: (纸本)9781450376570

At present, Rapid IO has been widely used in embedded platforms due to its high transmission efficiency and low transmission delay, making the software of the embedded platform a new speed. Windows system has the advantages of friendly interface, wide user base, easy maintenance and upgrade, etc., which has received extensive attention in the industry, but the real-time performance is poor and it is impossible to directly communicate with the embedded processor directly through Rapid IO, which makes it impossible to become a semi-physical simulation system. Therefore, the TSI721 driver development based on the RTX environment is designed. The internal structure of Rapid IO protocol, RTX real-time subsystem and Tsi721 switch chip is briefly described. Detailed description of the development framework and interface design of the Tsi721Pcie driver, the main process of RTX driver development. Experiments verify that PCIe and RTX drivers are stable, reliable, and capable of completing tasks in real time. © 2019 Association for Computing Machinery.

关键词： Software design

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Efficient combination of ionic-liquid-based ultrasound-assisted extraction, complex chromatography, and molecular docking for screening of acetylcholinesterase inhibitors from Ganoderma atrum

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JOURNAL OF FOOD MEASUREMENT AND CHARACTERIZATION 2023年第2期17卷 1228-1240页

作者： Hou, Wanchao liu, Chunming li, Sainan Niu, Huazhou liu, Zhen Zhang, Yuchi Jin, Yongri li, xuwen Jilin Univ Coll Chem Changchun 130021 Jilin Peoples R China Changchun Normal Univ Cent Lab Changchun 130032 Peoples R China

Compounds extracted from Ganoderma atrum (G. atrum) is significantly beneficial to human health, have been incorporated in numerous remedies owing to their brain and kidney health benefits and antiinflammatory and diuretic properties. G. atrum a pilot of homology of medicine and food, has an important development value of functional food and health food. In this study, to develop a new ionic-liquid-based ultrasound-assisted extraction method and bio-affinity ultrafiltration coupled with LC and MS. Moreover, molecular docking was used to evaluate the activity of the AChE inhibitors, which were subsequently isolated and purified using consecutive counter-current chromatography (CCC) and semi-preparative high-performance liquid chromatography (HPLC). Lastly, the active compounds were identified using MS and nuclear magnetic resonance. Four AChE inhibitors, viz. ergosterol, ergosta-7,22-dien-3-one, ergosta-7-en-3 beta-ol, and ergosta-4,6,8(14),22-tetraen-3-one with purities of 92.23%, 90.19%, 90.52% and 96.72%, respectively, were obtained from G. atrum using consecutive CCC (ethyl acetate/methanol/water, 4.0:1.0:7.0, v/v/v) coupled with semi-preparative HPLC (4% A (0-30 min), 4-100% A (30-40 min)). Our results suggested that G. atrum extracts can be used in the potential prevention and treatment of neurodegenerative diseases. It will help to elucidate the mechanisms of action of various medicinal plants at the molecular level and provide more opportunities to discover and develop new potential therapeutic remedies from health care food resources.

关键词： Ganoderma atrum Ionic-liquid Acetylcholinesterase Inhibitor molecular Docking chromatography

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Interaction Between Tangeretin and Ovalbumin to Reduce the Allergic Effects of Ovalbumin

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Chemical Research in Chinese Universities 2016年第4期32卷 556-560页

作者： SHI Xiaolei ZHANG Ting li xuwen FENG Yu TAN Xin JIN Yongri College of Food Science and Engineering Jilin University Changchun 130062 P. R. China College of Chemistry Jilin University Changchun 130012 P. R. China

Food allergy has become a worldwide problem. To find an effective way to reduce the allergic effect of allergen is an interesting topic. In this work, the interaction between ovalbumin（OVA） and tangeretin was studied by means of spectroscopy, molecular docking calculation and animal experiment. As the results show, static quenching of fluorescence intensity happened due to the interaction between OVA and tangeretin. Binding constants, binding sites, and thermometric parameters were obtained. The conformation changing of OVA occurred due to the interaction between it and tangeretin. The molecular docking calculation results show that the epitopes Arginine 84（ARG84）, Leucine 87（LEU87）, Asparagine 88（ASN88）, Serine 103（SER103）, Arginine 104（ARG104）, Leucine 124（LEUI24）, Arginine 126（ARG126）, Glycine 127（GLY127）, Glycine 128（GLY128） and Tryptohan 148（TRP148） of OVA were occupied by tangeretin after the docking, which means tangeretin may have some inhibition effects. As the results of animal experiments, the amount of IgE and lung tissue sections of female BALB/c mice in different groups show that tangeretin with different concentrations has better effects than dexamethasone. In conclusion, the tangeretin may have the effects to reduce the allergic effects of OVA via occupying the IgE-binding epitopes of OVA.

关键词： Tangeretin Ovalbumin Interaction Epitope Conformation

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Polyoxygenated anti-inflammatory biscembranoids from the soft coral Sarcophyton tortuosum and their stereochemistry

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Chinese Chemical Letters 2021年第1期32卷 271-276页

作者： Yufen li Songwei li Cristina Cuadrado Chenglong Gao Qihao Wu Xiaolu li Tao Pang Antonio Hernandez Daranas Yuewei Guo xuwen li State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China School of Chinese Materia Medica Nanjing University of Chinese MedicineNanjing 210023China Instituto de Productos Naturalesy Agrobiologi’a Consejo Superior de Investigaciones Científicas(IPNA-CSIC)La Laguna 38206Spain Jiangsu Key Laboratory of Drug Screening State Key Laboratory of Natural MedicinesJiangsu Key Laboratory of Drug Discovery for Metabolic DiseasesChina Pharmaceutical UniversityNanjing210009 China

Five novel biscembranoids,ximaolides H-L(1-5),along with four known related compounds(6-9) were isolated from the Hainan soft coral Sarcophyton *** structures of the new compounds were determined by extensive spectroscopic analysis,quantum chemical calculations,and/or by comparing their CD spectra with those of the known *** 1 and 2 are the first examples of biscembranoids bearing a 1,35-bridged lactone moiety,4 is the first biscembranoid comprising an uncommon oxetane ring,and 5 represents the first 36-peroxyl *** Ⅰ(2),K(4) and F(9) exhibited interesting anti-inflammatory activity by the inhibition of LPS-induced TNF-α protein release in RAW264.7 macrophages.

关键词： Soft coral Sarcophyton tortuosum Biscembranoid Stereochemistry Anti-inflammatory

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Determination of hyperin in seed of Cuscuta chinensis Lam. by enhanced chemiluminescence of CdTe quantum dots on calcein/K₃Fe(CN)₆ system

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FOOD CHEMISTRY 2012年第4期134卷 2383-2388页

作者： Kang, Jing li, xuwen Geng, Jiayang Han, Lu Tang, Jieli Jin, Yongri Zhang, Yihua Jilin Univ Coll Chem Dept Analyt Chem Changchun 130012 Peoples R China

In this paper, 3-mercaptocarboxylic acid (MPA) modified CdTe quantum dots (QDs) were used as sensitizers, to enhance the chemiluminescence (CL) of the calcein/K3Fe(CN)(6) system. A new CL system of CdTe/calcein/K3Fe(CN)(6) was developed. The effects of reactant concentrations and the particle sizes of CdTe QDs on the CL emission were investigated in detail. The possible enhancement mechanism of the CL was also further investigated based on the photoluminescence (PL) and CL spectra. Polyphenols such as chlorogenic acid, quercetin, hyperin, catechin and kaempferol, were observed to inhibit the CL signal of the CdTe/calcein/K3Fe(CN)(6) system and determined by the proposed method. The proposed method was applied to the determination of hyperin in seed of Cuscuta chinensis Lam, and the results obtained were satisfactory. (C) 2012 Elsevier Ltd. All rights reserved.

关键词： Chemiluminescence CdTe quantum dots Polyphenols Seed of Cuscuta chinensis Lam.

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A Review of Visual Estimation Research on live Pig Weight

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SENSORS 2024年第21期24卷 7093页

作者： Wang, Zhaoyang li, Qifeng Yu, Qinyang Qian, Wentai Gao, Ronghua Wang, Rong Wu, Tonghui li, xuwen China Agr Univ Coll Informat & Elect Engn Beijing 100083 Peoples R China Beijing Acad Agr & Forestry Sci Res Ctr Informat Technol Beijing 100097 Peoples R China Huazhong Agr Univ Coll Informat Wuhan 430070 Peoples R China Shanxi Agr Univ Coll Agr Engn Jinzhong 030801 Peoples R China Tianjin Agr Univ Coll Comp & Informat Engn Tianjin 300384 Peoples R China

The weight of live pigs is directly related to their health, nutrition management, disease prevention and control, and the overall economic benefits to livestock enterprises. Direct weighing can induce stress responses in pigs, leading to decreased productivity. Therefore, modern livestock industries are increasingly turning to non-contact techniques for estimating pig weight, such as automated monitoring systems based on computer vision. These technologies provide continuous, real-time weight-monitoring data without disrupting the pigs' normal activities or causing stress, thereby enhancing breeding efficiency and management levels. Two methods of pig weight estimation based on image and point cloud data are comprehensively analyzed in this paper. We first analyze the advantages and disadvantages of the two methods and then discuss the main problems and challenges in the field of pig weight estimation technology. Finally, we predict the key research areas and development directions in the future.

关键词： weight estimation non-contact computer vision image analysis point cloud stereoscopic vision

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