高黏度头孢菌素C发酵液的超滤研究

利用新型的板式超滤系统对高黏度头孢菌素C发酵液进行了澄清实验研究,通过实验数据与现有系统的运行数据对比,该系统基本解决了目前国内头孢菌素C发酵液超滤提纯中存在的主要过滤问题.     

新型无卤阻燃剂六苯胺基环三磷腈的合成

由五氯化磷和氯化铵合成了六氯环三磷腈（Ⅰ），通过亲和取代反应由苯胺和Ⅰ合成了六（苯胺基）环三磷腈（Ⅱ），对反应条件进行了优化，并对化合物Ⅰ、Ⅱ进行了元素分析、IR谱和质谱表征。用化合物Ⅱ与ABS树脂共混制备了阻燃ABS树脂，测试了其氧指数和力学性能等指标。     

中试规模制备L-茶氨酸及其衍生物

报道了中试规模制备L-茶氨酸和L-谷氨酰胺的一种方法。以廉价的L-谷氨酸为原料,采用邻苯二甲酰基作为保护基,保护L-谷氨酸的α-氨基,醋酐回流10 m in使其分子内脱水生成N-邻苯二甲酰-L-谷氨酸酐,在常温、常压条件下,分别与2 mol/L氨水和2 mol/L乙胺水溶液反应生成中间产物N-邻苯二甲酰-L-谷氨酰胺、N-邻苯二甲酰-L-茶氨酸,中间产物在室温条件下与0.5 mol/L水合肼反应48 h脱除保护基,分别以57%、61%的收率得到L-谷氨酰胺和L-茶氨酸。     

Effective naive Bayes nearest neighbor based image classification on GPU

Non-parametric classifier, Naive Bayes nearest neighbor, is designed with no training phase, and its performance outperforms many well-trained learning-based image classifiers. Unfortunately, despite its high accuracy, it suffers from great computational pressure from distance computations in space of local feature. This paper explores accelerating strategies from perspectives of both algorithm design and software development. Our approach integrates space decomposition capability of Product quantization (PQ) and parallel accelerating capability of underlying computational platform, Graphics processing unit (GPU). PQ is exploited to compress the indexed local features and prune the search space. GPU is used to ease most of computational pressure by processing the tasks in parallel. To achieve good parallel efficiency, a new sequential classification process is first designed and decomposed into independent components with high parallelism. Effective parallelization techniques are then presented to make use of computational resources. Parallel heap array is built to accelerate the process of feature quantization. Distance table lookup is built to speed up the process of feature search. Comparative experiments on UIUC-Sport dataset demonstrate that our integrated solution outperforms other implementations significantly on Core-quad Intel Core i7 950 CPU and GPU of NVIDIA Geforce GTX460. Scalability experiment on 80 million tiny images database shows that our approach still performs well when large-scale image database is explored.     

炭黑密相气力输送系统设计

随着橡胶工业的发展，以及气力输送特有的优点，气力输送系统越来越广泛地应用于输送炭黑的过程中。以炭黑气力输送系统为研究对象，详细介绍了系统设计的基本参数确定、气力输送形式的确定、压送罐客积的设计、输送管道的设计，并通过输送系统压力降的计算验证了设计参数的取值是合理的。     

对新建大型尿素工艺技术路线的选择

“九五”期间，为满足农业发展的需要，国内将新建一批大型尿素装置，本文对如何更好地选择先进、成熟可靠且经济效益突出的工艺提出一些思考。     

PbNb2O6基压电陶瓷的高温介电性能研究

本文在PbNb2O6基础上采用Ba^2＋取代Pb^2＋离子,并通过添加Cr2O3、Y2O3、Sm2O3、Nd2O3和CeO2等氧化物进行掺杂改性,研究不同掺杂剂对PbNb2O6陶瓷材料结构的影响,寻找提高压电性能及居里温度的途径.试验结果表明,掺杂后的偏铌酸铅显微结构发生了变化,适量的掺杂可获得压电性能和工艺稳定性能很好,且居里温度较高（420℃～600℃）的改性PbNb2O6系压电陶瓷,可分别满足350℃和500℃以上高温应用环境的要求.     

A GPU-based parallel method for evolutionary tree construction

Evolutionary trees are widely applied in various applications to show the inferred evolutionary relationships among species or entities. Neighbor-Joining is one solution for data-intensive and time-consuming evolutionary tree construction, with polynomial time complexity. However, its performance becomes poorer with the growth of massive datasets. Graphics Processing Units (GPUs) have brought about new opportunities for these time-consuming applications. Based on its high efficiency, a GPU-based parallel Neighbor-Joining method is proposed, and two efficient parallel mechanisms, data segmentation with asynchronous processing and the minimal chain model with bitonic sort, are put forward to speed up the processing. The experimental results show that an average speedup of 25.1 is achieved and even approximately 30 can be obtained with a sequence dataset ranging from 16,000 to 25,000. Moreover, the proposed parallel mechanisms can be effectively exploited in some other high performance applications.     

矿用多协议嵌入式网关设计

针对目前煤矿中异构网络之间通信困难、信息融合不便、监测监控信息不能及时传送等问题,本文设计实现了一种矿井多协议嵌入式网关。该网关基于uC/OS-Ⅱ嵌入式操作系统,移植LwIP网络协议实现RS232、RS485、CAN和以太网之间的协议转换;硬件核心采用ST公司STM32F107,该芯片以ARM Cortex-M3内核,集成各种高性能工业标准接口,更适应于高性能、低成本、低功耗的嵌入式应用。     

沥青表面形貌的表征与测试及其对与集料接触特性的影响

采用原子力显微镜对SK90#基质沥青和SBSⅠ-C改性沥青的表面形貌进行了测试,获得了两种沥青的表面形貌参数,并基于此对沥青的表面形貌特性进行了分析;基于沥青表面的高度概率密度曲线和承载面曲线,从界面实际接触面积的角度分析了沥青表面特性对与集料接触特性的影响.结果表明,SBSⅠ-C改性沥青的表面起伏情况高于SK90#基质沥青,具有更大的表面粗糙度.具有更大Ssk(歪斜度)的沥青更有利于形成更好的黏附强度,但也更容易发生磨损而使黏附性能快速降低.沥青与集料间的接触性能受其实际接触面积的影响,SBSⅠ-C改性沥青具有与集料更大的实际接触面积,从而形成更大的摩擦力而具有更优良的黏附性能.