GC-MS分析法在猪肉氯霉素残留检测中的应用

建立了猪肉中残留氯霉素(CAP)的GC-MS分析方法。样品中CAP用乙酸乙酯提取,脂肪用正己烷去除,BondElut-C18柱纯化样品,BSTFA-TMCS衍生后用NCI源选择m/z为466的特征离子为目标离子,在SIM模式下进行GC-MS分析。被检测CAP质量浓度在0.08~100μg/kg内,方法的线性关系良好,相关系数为0.998。方法的最低检测限达到0.08μg/kg。用此方法对市场上销售的猪肉样品进行测定,结果显示:只有一份样品CAP残留量为(0.236±0.007)μg/kg,另4份猪肉样品中未检出CAP残留。应用本方法测定新鲜猪肉中CAP残留,基本上满足了灵敏、快速、准确可靠的分析方法要求。     

采用面向对象技术设计实现逻辑链路控制和适配协议

逻辑链路控制和适配协议是蓝牙协议栈中数据链路层的一部分。利用面向对象的分析和设计思想,应用标准建模语言的建模技术,对L2CAP协议进行了设计和实现。     

一种基于LINUX操作系统的安全增强实现思路

针对传统操作系统存在的安全缺陷,作者提出了一个将几种安全策略和机制有机结合,很好地弥补安全缺陷的基于LINUX的安全增强实现思路。     

电子政务系统中的访问控制研究

该文根据对一些应用中的访问模式及特点的分析,提出了将PAC与CAP相结合的新型访问控制模型,该模型能够很好地对系统中的数据对象进行保护。     

PECAP: Priority-Based Delay Alleviation Algorithm for IEEE 802.15.4 Beacon-Enabled Networks

A new priority-based algorithm for IEEE 802.15.4 beacon-enabled networks is proposed in order to alleviate an end-to-end delay while maintaining energy efficiency. In this paper, the active period is temporally increased to reduce the sleep delay that makes up a large portion of the end-to-end delay. Nodes having high-priority packets request the coordinator to execute an extended contention access period by sending a priority toning signal. The simulation results show that the proposed algorithm alleviates the end-to-end delay of high priority packets.     

代建制项目的信息集成管理研究

信息管理往往是工程项目管理中的薄弱环节,本文针对代建制项目的特点,提出了代建制项目中信息集成应以项目管理公司为核心,以现代化的网络技术为手段,通过集成化项目管理信息系统(IPMIS)实现。在论述了信息集成的必要性之后,从时间、目标、功能和主体四个维度进行分析,并建立了较为系统的集成化项目管理信息系统框架模型。     

ADSL技术发展及其应用

ADSL（Asymmetrical Diital Subscriber Loop,非对称数字用户环路）技术是一种调制技术,在双绞铜线的两端分别接入ADSL调制解调器,即可利用其高频宽带特性高速传送数据。本文全面阐述了实现用户线路高速化的ADSL技术基础及其应用。     

CAP1400主管道用112t电渣锭研制

利用自主研发的大型电渣技术,生产出CAP1400主管道用超低碳控氮不锈钢SA376 TP316LN 112 t电渣锭。电渣重熔的关键则是有效保证超低碳氮含量、高纯净度和高均匀性。     

Argon Plasma Exposure Augments Costimulatory Ligands and Cytokine Release in Human Monocyte-Derived Dendritic Cells

Cold physical plasma is a partially ionized gas expelling many reactive oxygen and nitrogen species (ROS/RNS). Several plasma devices have been licensed for medical use in dermatology, and recent experimental studies suggest their putative role in cancer treatment. In cancer therapies with an immunological dimension, successful antigen presentation and inflammation modulation is a key hallmark to elicit antitumor immunity. Dendritic cells (DCs) are critical for this task. However, the inflammatory consequences of DCs following plasma exposure are unknown. To this end, human monocyte-derived DCs (moDCs) were expanded from isolated human primary monocytes; exposed to plasma; and their metabolic activity, surface marker expression, and cytokine profiles were analyzed. As controls, hydrogen peroxide, hypochlorous acid, and peroxynitrite were used. Among all types of ROS/RNS-mediated treatments, plasma exposure exerted the most notable increase of activation markers at 24 h such as CD25, CD40, and CD83 known to be crucial for T cell costimulation. Moreover, the treatments increased interleukin (IL)-1α, IL-6, and IL-23. Altogether, this study suggests plasma treatment augmenting costimulatory ligand and cytokine expression in human moDCs, which might exert beneficial effects in the tumor microenvironment.     

上市公司竞争优势的资本市场评价方法

传统的竞争优势评价方法，无论是定性分析还是定量分析，都是以企业为应用主体的实务分析方法。与此不同，股市投资者往往通过判断上市公司是否具有长期获益的能力来评价其竞争优势。提出了一种面向投资者的资本市场评价方法，即利用竞争优势持续期——企业能够获取超额收益的持续时间，来评价上市公司的相对竞争地位。建立了企业竞争优势与股票估值的理论基础，深入分析了上市公司竞争优势与经济附加值的关系。研究表明，竞争优势持续期不但可以综合反映上市公司的盈利能力和未来发展前景，而且能指示上市公司的相对竞争地位。还构建了易于应用的竞争优势持续期评估模型。