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农业机械学报 2000年第2期31卷 42-45页

作者：董锋耿端阳汪遵元山东工程学院机械工程系淄博市255012 山东工程学院汽车工程系

介绍带式喂入钵苗栽植机工艺流程和工作原理。对影响生产效率和栽植质量的因素进行了研究 ,确定了喂入和栽植的最佳参数。检测表明 :该机生产率 84株 / (行· m in) ,株距合格率 95 % ,栽直率 90 .5 %

关键词：栽植机设计钵苗栽植带式喂入工作原理

Dehalogenation of benzofuran derivatives

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Dehalogenation of benzofuran derivatives

Preparation and Process Parameters of Matrine/PLGA Microspheresby a Phase Separation/Deposition Process

2013年中国药学大会暨第十三届中国药师周

作者： wang zunyuan Yang Yewei Ma Zhen Zhang Ping Huang Wenhai Liang Meihao Shen Zhongrong Zhejiang Academy of Medical Sciences

Benzo[b]furan derivatives are of considerable interest because of their widespread occurrence among natural products and their physiological properties. They are also key starting materials for the synthesis of various medical products[1-6]. A halogen atom, useally bromo or ido, is often introduced to a given position of an arene or a heterocyclic compound to make them as a blocking group[7–11]. Occasionally, it is introduced from the side reactions[12]. So, the dehalogenation is an important chemical transformation in organic synthesis and environmental remediation[13-15]. Many dehalogenation methods have been developed by employing palladium as the catalysts recent years[16], because palladium catalyst is a very stable, inexpensive, and readily commercially available. However, to the best of our knowledge, most of the reported methodologies are using aryl halides, especially aryl chlorides[17-20], and a few dehalogenation methods were performed in the heterocyclic, especially in benzo[b]furan derivatives. Here we report the first use of palladium acetate in the presence of phosphine ligands to remove the halogen atom in benzo[b]furan derivatives. Using 3-bromo-2-butyl-5-methanesulfonylaminobenzofuran as a model compound, and palladium acetate as the catalyst, various phosphine ligands（1-5） were screened in the precence of K 3 PO 4 in toluene, at a temprature of 100 ℃ for 48h. The ligand 3 was found to be the best in high conversion of almost 100%. The chemically combined water of K 3 PO 4 ·2H 2 O crystallization was assumed as the the hydrogen source in the reaction. The reaction was repeated and confirmed by other seven benzo[b]furan bromides. Scheme 1 summarizes our preliminary results for these debromination reactions.

关键词： dehalogenation benzofuran catalysis

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Preparation and Process Parameters of Matrine/PLGA Microsphe...

第九届全国生物材料学术会议（CBMS-9）

作者： Ma Zhen wang zunyuan Peng Xiaoying Shen Zhengrong (Institute of Materia Medico, Zhejiang Academy of Medical Sciences, Hangxhou 310013)

＜正＞ Microspheres prepared from poly （lactide-co-glycolide）, PLGA, were widely studied and clinically used for controlled release drug delivery systems. Matrine, one of the alkaloids from Sophora flavescens called kushen by the Chinese, which has been used clinically to treat a wide range of ailments, was found to have the effect of inhibiting mice ascites carcinoma in vivo and in vitro recent years, with a therapeutic index 7. 8 times higher than a common chemotherapeutic agent called mitomycin C. To design a high efficiency, low toxicity and prolonged release preparation of matrine for anti-cancer purpose, microspheres containing matrine were prepared by a phase separation/deposition process. Various parameters in the preparing process were studied, such as stabilizer, polymer concentration, temperature, stirring speed, time, drop addition speed, solidification time, ect. A prefer condition and preparation process was described *** a solution of PLGA 7. 0 g in 7ml Span-80 and 700 ml chloroform, 1. 24 g matrine was added. The temperature was decreased to 0-5 ℃in an ice bath. After stirring for 13min at 700 rpm, 650 ml petrol ether was added drop wise in about 2. 5 h, and microspheres formed within this procedure. Another 200 ml petrol ether was added in 30 min to solidify the microspheres. The resulting suspension was separated and collected by *** with the disadvantage of solvents such as petrol ether and chloroform wasteful, this preparing process of matrine/PLGA microspheres had the advantage of high yield, narrow size distribution, large-mass productivity, procedure facile and controllable. The tests of drug release in vitro and in vivo are in progress.

关键词： Microspheres Phase separation/deposition process Parameters Matrine

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移动式土壤工作部件性能参数测试系统

农业机械学报 2000年第2期31卷 35-38页

作者：马明建汪遵元尹凤福郭志东山东工程学院农业工程系淄博市255012

介绍了基于土槽的土壤工作部件性能参数测试系统的构成、关键技术问题的处理 ,论述了一种定点等距采集数据的方法 ,该方法采用计算机软件对机组的位移脉冲信号连续计数 ,以确定采样点的位置和采集牵引阻力等数据。试验表明 ,采用定点等... 详细信息

介绍了基于土槽的土壤工作部件性能参数测试系统的构成、关键技术问题的处理 ,论述了一种定点等距采集数据的方法 ,该方法采用计算机软件对机组的位移脉冲信号连续计数 ,以确定采样点的位置和采集牵引阻力等数据。试验表明 ,采用定点等距采集数据方法的系统不仅具有结构简单、可动态显示数据等优点 ,而且便于离线定点研究土壤坚实度。

关键词：移动式土壤工作部件性能测试系统定点测试

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温室风向风速测试系统的研究设计

农业工程学报 2000年第4期16卷 115-117页

作者：马明建郭志东汪遵元尹风福山东工程学院

该文介绍温室数字式风向风速传感器的工作原理、电路原理、风向风速信号测试系统的结构、风向信号的数据采集方法、风速脉冲信号的软件计数算法、风速脉冲信号计数程序运行周期的分析。实验结果表明 ,系统结构简单 ,可靠性好 ,抗干扰能... 详细信息

该文介绍温室数字式风向风速传感器的工作原理、电路原理、风向风速信号测试系统的结构、风向信号的数据采集方法、风速脉冲信号的软件计数算法、风速脉冲信号计数程序运行周期的分析。实验结果表明 ,系统结构简单 ,可靠性好 ,抗干扰能力强 ,测量精度高。

关键词：温室风向风速测试系统传感器数据采集

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带式钵苗喂入系统的分析与试验(英文)

农业工程学报 2001年第1期17卷 74-77页

作者：董锋柏雪源闸建文汪遵元山东工程学院淄博255012

简要介绍了由带式钵苗喂入系统和导苗管式栽植系统组成的钵苗栽植机的工作原理 ,而对本机创新点——输送带式钵苗喂入系统作了较为详细的分析 ;提出了向导苗管式栽植器喂入钵苗的基本要求 ;通过计算和试验 ,讨论了输送带的传动比、输送... 详细信息

简要介绍了由带式钵苗喂入系统和导苗管式栽植系统组成的钵苗栽植机的工作原理 ,而对本机创新点——输送带式钵苗喂入系统作了较为详细的分析 ;提出了向导苗管式栽植器喂入钵苗的基本要求 ;通过计算和试验 ,讨论了输送带的传动比、输送带长度、送钵时间、分钵器主要参数对生产率、栽植株距及均匀性和操作者劳动强度的影响 ,还讨论了保证钵苗喂入连续性的条件 ;应用刚体平面运动理论对钵苗在输送带末端的翻倒以及在扶正器作用下的转正过程进行描述。试验表明该喂入系统操作简单、分钵可靠、喂入姿态合理。

关键词：移栽机钵苗输送带喂入机构

Copolymerization of MDD with ε-CL

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Copolymerization of MDD with ε-CL