Advanced FO membranes from newly synthesized CAP polymer for wastewater reclamation through an integrated FO‐MD hybrid system

A new cellulose acetate propionate (CAP) polymer has been synthesized and used to prepare high‐performance forward osmosis (FO) membranes. With an almost equal degree of substitution of acetyl and propionyl groups, the CAP‐based dense membranes show more balanced physicochemical properties than conventional cellulose acetate (CA)‐based membranes for FO applications. The former have a lower equilibrium water content (6.6 wt. %), a lower salt diffusivity (1.6×10¹⁴ m² s^?1) and a much lower salt partition coefficient (0.013) compared with the latter. The as‐prepared and annealed CAP‐based hollow fibers have a rough surface with an average pore radius of 0.31 nm and a molecular weight cut off of 226 Da. At a transmembrane pressure of 1 bar, the dual‐layer CAP‐CA hollow fibers show a pure water permeability of 0.80 L m^?2 h^?1 bar^?1 (LMH/bar) and a rejection of 75.5% to NaCl. The CAP‐CA hollow fibers were first tested for their FO performance using 2.0 M NaCl draw solution and deionized water feed. An impressive water flux of 17.5 L m^?2 h^?1 (LMH) and a reverse salt flux of 2.5 g m^?2 h^?1 (gMH) were achieved with the draw solution running against the active CAP layer in the FO tests. The very low reverse salt flux is mainly resulting from the low salt diffusivity and salt partition coefficient of the CAP material. In a hybrid system combining FO and membrane distillation for wastewater reclamation, the newly developed hollow fibers show very encouraging results, that is, water production rate being 13–13.7 LMH, with a MgCl₂ draw solution of only 0.5 M and an operating temperature of 343 K due to the incorporation of bulky propionyl groups with balanced physiochemical properties. © 2012 American Institute of Chemical Engineers AIChE J, 59: 1245–1254, 2013     

基于TMS320F28335的雷达发射机实时脉冲占空比的检测

介绍了雷达发射机脉冲占空比检测的重要性,给出了利用TI公司的TMS320F28335实现发射机脉冲占空比检测的工作原理、设计思路、电路结构和软件设计,并在此基础上进行了实验验证。结果表明,该检测电路性能良好。     

CAP1400安全壳和模块整体出厂时大件码头及场内设施改造方案分析

从CAP1400核电钢制安全壳和模块整体出厂的构想尚存在诸多不确定因素切入,按照模块整体出厂参数,依据已审批的3 000~5 000 t级核电站码头初步设计资料、SG浮吊卸货运输方案、拟采用18 000 t级半潜船运输构想、重件道路等场内设施初步设计参数,对码头、场内设施等设计方案按照理想状态同比例放大航道、港池、码头、重件道路等参数建立模型,进行模块整体出厂的改造分析.经过对船型参数、航道、港池、码头、场内设施详细的技术与经济对比分析,对模块整体出厂从理论、安全、技术、经济等方面给出了切合实际的建议.     

Determination of chloramphenicol residues in commercial chicken eggs in the Federal Capital Territory,Abuja, Nigeria

The use of antibiotics in poultry can result in residues in eggs. The joint FAO/WHO committee recommended banning the use of chloramphenicol (CAP) in food animals due to its public health hazards of aplastic anaemia, leukaemia, allergy, antibacterial resistance and carcinogenicity. This paper determines the prevalence of CAP residues in chicken eggs and assesses the usage and awareness of its ban amongst poultry farmers in the Federal Capital Territory (FCT), Abuja, Nigeria. A cross-sectional survey of registered poultry farmers in FCT was conducted using questionnaires to determine CAP administration in poultry and awareness of its ban. Pooled egg samples were collected from each poultry farm surveyed and from randomly sampled government-owned markets in FCT. Source of eggs by state were identified by the marketer at the time of collection. Samples were analysed using an enzyme-linked immunosorbent assay (ELISA) technique for the presence of CAP, and prevalence was determined. Of 288 total pooled samples collected, 257 (89.2%) were from the markets and 31 (10.8%) were from poultry farms. A total of 20 (7%) pooled egg samples tested CAP-positive; market eggs originated from 15 (41%) states of the country. Of the market eggs, 16 (6.2%) pooled samples tested positive. Of eggs from poultry farms, four (12.9%) tested positive. Mean CAP concentrations in the positive samples ranged from 0.49 to 1.17 µg kg^?1 (parts per billion). CAP use amongst poultry farmers in FCT was 75.5%; awareness of the CAP ban was 26.3%. Though 66% of veterinarians were unaware of a CAP ban, they were more likely to be aware than other poultry farmers (odds ratio (OR) = 1.4). Farm managers who use CAP were more likely to be aware of CAP ban than the farm managers not using CAP (OR = 5.5; p = 0.04). Establishing a drug residue surveillance and control program and enforcement of CAP legislation/regulation is needful to educate and prohibit the widespread CAP use amongst Nigerian poultry farmers.     

基于设计分析器的CAP1400核电厂非安全级仪控系统控制逻辑设计验证

从设计院的角度给出核电厂控制逻辑设计验证的要点、方法和流程,并以CAP1400项目具体的控制逻辑验证为例,介绍在设计过程中如何基于设计分析器开展控制逻辑图的验证工作。     

移动智能网独立智能外设的设计与实现

提出了独立智能外设的设计方案 ,列举了主要的信令流程 ,包括独立智能外设内部实体间的消息交互 . 指出了下一代 IP的研究方向.     

蓝牙系统逻辑链路控制和适应协议的分析

蓝牙（Bluetooth）技术是便携式电子设备和固定式电子设备之间代替电缆联接的短距离无线通信的标准。蓝牙系统是用于短距离内无线数字设备之间进行数据通信的二组协议的集合。逻辑链路控制和适应协议是蓝牙系统的核心协议之一。对蓝牙系统逻辑链路控制和适应协议的功能和协议结构作了详细的分析和讨论。     

Polymers with pH-Dependent Solubility: Possibility of Use in the Formulation of Gastroresistant and Controlled-Release Matrix Tablets

Polymers usually utilized for gastroresistant film coating of tablets or pellets such as cellulose acetate phthalate (CAP), cellulose acetate trimellitate (CAT), hydroxypropylmethylcellulose phthalate (HPMCP), and Eudragit L and S were used in the preparation of drug/polymer matrix tablets. These tablets were prepared either by direct compression of both powders or by the formulation of microspheres that were then compressed. The microspheres were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and X-ray diffractometry analyses. Dissolution studies were finally carried out to verify if the tablets possessed gastroresistant or controlled-release characteristics. Except for Eudragit L, the polymers can be used under certain conditions in the formulation of modified-release tablets.     

虾仁中氯霉素残留量的气相色谱测定

建立了用配有电子俘获检测器(ECD)的气相色谱仪来测定虾仁中的氯霉素含量的方法。试样用乙酸乙酯提取,正己烷去杂,硅胶柱纯化.BSTFA+TMCS(99:1)试剂硅烷化。以GC-ECD方式测定,外标法定量。当添加水平为0.2×10~9～1.0×10~(-9)μg/kg时,回收率为70%～110%;相对标准偏差为1.0%～5.0%;线性相关系数,r>0.998。