星点设计-效应面优化乳化交联法制备恩诺沙星壳聚糖微球

以平均粒径、载药量、包封率及总评归一值为评价指标,运用星点设计考察芯材比、油水相比、壳聚糖浓度对微球制备的影响,对结果进行二项式拟合,效应面法选取最佳工艺条件并进行预测分析。结果显示,最佳工艺条件为：油水相比为4.2∶1,壳聚糖浓度为2%,交联时间为3.5 h。在此条件下,制得的微球粒径均一,球形圆整,平均粒径为7.21μm,包封率为61.34%,载药量为70.12%。体外释放行为符合Higuchi方程,2 h和24 h时累积释放率分别为32%和84%。     

欢2-平1水平井钻井技术

欢2-平1井是辽河油田第一口稀油水平井探井,油藏类型为层状边水油藏,施工过程中克服了钻经地层松散、成岩性较差、水平段中靶精度要求高、地层易漏失等技术难题。文中对欢2-平1井的工程设计、轨迹控制技术、钻井液技术、完井技术进行了介绍,施工中对出现的漏失采取了适宜的解决措施,给出了实施稀油水平井的认识和体会。     

新型飞剪机结构探讨

介绍分析了传统飞剪机的缺点和新型飞剪机的工作原理,通过对比新型飞剪机的三种曲柄机构：四曲拐轴式、八曲拐轴式、双曲拐轴式,并结合国内外飞剪机的发展状况,从结构、制造和装配精度方面考虑,指出4曲拐轴式结构更适合于国情。这一新型飞剪机的研制成功,必将带动国内开卷线制造业的整体水平的提高。     

插座簧片多工位级进模设计

分析了插座簧片零件的冲压工艺,阐述了采用多工位级进模生产的可能性,介绍了冲压件的排样设计、模具结构特点及模具关键零件设计.对同类零件的模具设计有一定的借鉴作用.     

Development of 50MW S-band klystron

This letter reports the development of a 50MW S-band klystron in the Institute of Electronics, Chinese Academy of Sciences （IECAS）. It adopted a structure of six-cavity and single output window. Under conditions of an RF （Radio Frequency） pulse width of 4t, ts, a beam voltage of 305,9kV and a beam current of 368A, the peak output power has achieved 51.4MW with an efficiency of 45.6% and a gain of 54dB.     

高速印制电路板设计中的串扰问题和抑制

本文剖析了在高速PCB板级设计中信号完整性分析领域信号串扰的产生机制,并利用HyperLynx软件包仿真,结合工作中的实践,提出了相应的解决方案.     

高速电路印刷电路板的可靠性设计

在高速电路系统中,过高的系统工作频率将产生传输线效应和信号完整性问题,使得基于传统方法设计的印刷电路板(PCB)达不到系统可靠性要求.本文以电力电子控制器高速DSP系统为例,并结合TMS320F2612 PCB制作过程中的实践经验,论述了电磁兼容技术在高速电路PCB设计中的应用,以及提高系统可靠性的设计方法.     

挤压处理下组织化核桃蛋白品质变化

作为核桃制油副产物的核桃蛋白是一种优质植物蛋白,核桃蛋白高值化利用,对核桃产业可持续发展具有重要意义。该研究采用挤压法对核桃蛋白进行组织化,考察挤压工艺参数对组织化核桃蛋白色泽、质构特性和组织化度的影响。通过采用单因素法,研究了挤压温度、水分含量、螺杆转速、喂料速度和冷却温度5个挤压工艺参数对组织化核桃蛋白的影响。根据单因素试验结果,选择挤压温度、水分含量和喂料速度三个参数为响应面实验的试验因素,以组织化度为响应值,应用响应面分析法对挤压工艺参数进行优化,得到了最优挤压工艺参数为挤压温度141 ℃,水分含量52.7%,螺杆转速160 r/min,喂料速度26 g/min,冷却温度65 ℃,此时组织化度为1.209。该研究为核桃蛋白基素肉开发奠定了基础。     

工程图纸扫描输入及矢量化在水利工程设计中的应用

工程图纸扫描输入入矢量化应用在水利工程设计中,既可缩短出图时间,又能提高设计效率及质量,对提高设计单位的ＣＡＤ出图率具有重要的作用。     

Shape transformation by boundary representation interpolation: A recursive approach to establishing face correspondences

The issues relating to the shape transformation problem are discussed and a new algorithm is presented for computing the transformation of one shape into another. In this algorithm, the boundary definitions of the two initial shapes are used and a mapping is established between the vertices and edges of the respective objects. New vertices and edges are introduced into the object definitions when necessary to establish a one-to-one vertex correspondence and to match connectivity relationships between vertices. These can then be used to do a vertex-to-vertex interpolation that maintains valid polyhedral topologies for all of the intermediate shapes. The algorithm establishes a mapping between areas of the object such that adjacency relationships are preserved. These areas are recursively subdivided so that adjacency relationships of subareas are also preserved. During subdivision, vertices and edges are added to the boundaries of subareas so that a one-to-one mapping is established between them. Subdivision continues until each subarea consists of a single face. The algorithm presented works for objects that are topologically equivalent to spheres and can easily be extended to other pairs of objects as long as they are topologically equivalent to each other.