酚酞型聚醚砜膜的制备与性能研究

本文利用水相沉淀聚合法成功地合成了丙烯腈(AN)-(二丙烯酰胺基)-二甲基丙烷磺酸(AM PS)共聚物,然后将其作为添加剂制备酚酞型聚醚砜膜,并进一步研究了添加剂用量对膜通量,膜截留率以及膜形态的影响.研究表明,随着添加剂用量的增加(从0到5%),膜在100 kPa下的水通量从230 L/m2.hr下降到125 L/m2.hr,对PEG 35000的截留率分别从0.5528增加到0.75.另外,利用场发射电子显微镜观察了膜断面,发现随着PAN-co-AM PS含量的增加,膜表皮层逐渐变厚,指状孔逐渐减少.     

Final report of the Color Additive Scientific Review Panel

The Color Additives Scientific Review Panel considered whether there was information sufficient to perform a carcinogenic risk assessment on the colors D&C Red No. 19 (R-19), D&C Red No. 37 (R-37), D&C Orange No. 17 (O-17), D&C Red No. 9 (R-9), D&C Red No. 8 (R-8) and FD&C Red No. 3 (R-3) and to evaluate the assessments sent to FDA as part of the petitions for use of the colors for drug and external uses by the Cosmetic, Toiletry and Fragrance Association (CTFA). There is a lack of human data concerning the colors for making a human health assessment, so the assessments are based upon the extrapolation of animal data. The risk assessments are determined for exposure to single chemicals. Excluded from consideration are possible effects from exposure to multiple chemicals, such as co-carcinogenesis, promotion, synergism, antagonism, etc. In the light of recent efforts in establishing a consensus in risk assessment, the Panel has determined that the CTFA assessments for R-10, O-17, and R-9 are consistent with present acceptable usages, although it questions some of the assumptions used in the assessments. The Panel identified a number of general assumptions made, and discusses their validity, their impact on total uncertainty, and the potential options to address the gaps in understanding that necessitate the assumption. The Panel also derived revised risk estimates using more "reasonable" assumptions than "worst-case" situations, for 90th percentile and average exposure. For those assumptions that are easily quantifiable, the Panel's estimates are less than an order of magnitude lower than the CTFA risk estimates, indicating that the underestimates and overestimates of the CTFA risk estimates tend to balance each other. The impact of most of the assumptions is not quantifiable. The assessment for R-3 is complicated by the fact that there is no good skin penetrance study for this color. It was assumed that the penetrance is similar to that of another water-soluble xanthene color, R-19. It is expected that the absorption of the color is not likely to exceed that of the smaller molecule, R-19. Therefore, the risk estimates are similar to the CTFA estimates, but with different reasoning. The estimates for R-8 and R-37 are different from the others in that there is a lack of any exposure or toxicological information on these colors.(ABSTRACT TRUNCATED AT 400 WORDS)     

磨料射流及高分子减阻改善射流性能的实验研究

本文设计了磨料射流系统及喷嘴结构,实验研究了磨料射流切割与破碎物料的性能,确定了磨料喷嘴出口的最佳长度,对清水和磨料溶液进行了射流冲击性能比较试验;并进一步在磨料射流中加入高分子聚合物添加剂,实验证明,高分子减阻剂同样对磨料射流性能有改善.     

Bad News Has Wings: Dread Risk Mediates Social Amplification in Risk Communication

Social diffusion of information amplifies risk through processes of birth, death, and distortion of message content. Dread risk—involving uncontrollable, fatal, involuntary, and catastrophic outcomes (e.g., terrorist attacks and nuclear accidents)—may be particularly susceptible to amplification because of the psychological biases inherent in dread risk avoidance. To test this, initially balanced information about high or low dread topics was given to a set of individuals who then communicated this information through diffusion chains, each person passing a message to the next. A subset of these chains were also reexposed to the original information. We measured prior knowledge, perceived risk before and after transmission, and, at each link, number of positive and negative statements. Results showed that the more a message was transmitted the more negative statements it contained. This was highest for the high dread topic. Increased perceived risk and production of negative messages was closely related to the amount of negative information that was received, with domain knowledge mitigating this effect. Reexposure to the initial information was ineffectual in reducing bias, demonstrating the enhanced danger of socially transmitted information.     

微量元素添加剂预混料配方设计

简述了微量元素在动物体内的生理作用,介绍了微量元素添加剂预混料配方设计应遵循的一般规律,提供了一个微量元素添加剂预混料的配方实例.     

On the foundations: Statistical models and inference

This paper presents an overview of some recent results concerning statistical models and inference. specifically: grounds for statistical models. types of models that simplify by standard probability analysis, the use of categorical information in the reduction of the model with data, and the role of additives in the inference process. The relevant technical material has been developed elsewhere.     

气质联用和红外光谱技术在塑料助剂剖析中的应用

介绍了用气质联用仪和红外光谱仪分析无机填料表面活性剂、无机填料、ACR、密封胶的实验方法，并举例说明气质联用仪和红外光谱仪作为高效、实用的分析工具在塑料助剂剖析中应用．     

食品添加剂课程的教学改革与实践

为了提高食品添加剂课程的教学质量,激发学生的学习积极性,论文以食品添加剂课程教改为研究课题,针对课程教学中存在的问题,从教学内容、教学方法、教学手段、考核方法等多个方面进行了研究和实践。结果证明,教学改革效果良好,不仅有利于培养学生的学习兴趣,而且有利于提高学生分析问题与解决问题的能力。     

我国食品添加剂标准的立法研究

"民以食为天",食品安全与人民群众的日常生活息息相关,随着一系列问题食品的出现,人们对于食品的安全问题越来越担忧。三鹿奶粉事件引发了社会各界的讨论,尤其是对于现行我国食品安全立法的思考。《食品安全法》的出台顺应了社会发展的要求,然而国家随后出台了三聚氰胺的限定含量标准,此举引起了学术界的广泛争议,对于三聚氰胺这样的非食品添加剂进行限定含量规定是否不妥,是否与现行法律相悖等等。《食品安全法》虽然出台了,但是与之相配套的法律体系并未建立,尤其是针对三鹿奶粉事件而出现的一些问题,如关于食品添加剂标准的立法还不够完善,相关规定缺乏可操作性等,应及时通过立法或司法解释加以完善。     

《塑料加工助剂》课程教学改革探索

塑料加工助剂在高分子材料加工中起着重要作用 ,然而其内容繁多 ,抽象难学 ,对学生基础要求较高。我们结合多年教学经验 ,对教学内容 ,教学方式 ,考核方式等多方面进行了探讨