Modeling and simulation of wet-end white water system in the paper mill

A dynamic model representing the wet-end of a paper mill is developed to characterize its dynamic behavior. The model is based on the mass balance relationships written for the simplified wet-end white water network. The dynamic response of the wet-end is influenced both by the white water volume and by the level of wire retention. Effects of key manipulated variables such as the thick stock flow rate, the ash flow rate and the retention aid rate on the major controlled variables are analyzed by numerical simulations. It can be said that the consistency of the model with plant data seems to be reasonably good and can be used as a tool for plant analysis and control.     

低渗透油藏注CO2驱油现状研究

低渗透油田最基本的特点就是流体渗透能力差、产能低,常规方式下采收率低。CO2作为一种驱油剂,在低渗油藏的开发中具有明显的增油降水效果,即CO2驱油技术在封存CO2,降低该温室气体对环境影响的同时,可以提高油田的采收率。通过探讨低渗透油藏注CO2提高原油采收率的驱油机理和应用现状,指出CO2在提高低渗油藏采收率方面大有可为。     

镍铁渣用作混合材对水泥性能影响的研究

研究了镍铁渣单掺作为混合材对水泥标准稠度需水量、凝结时间、强度等性能的影响,通过X射线衍射(XRD)、扫描电镜(SEM)、微量热仪等检测手段,揭示镍铁渣复合水泥微观结构与宏观性能之间的联系,并研究了镍铁渣与矿粉复掺对水泥强度的影响.研究结果表明,随着镍铁渣掺量的增加,水泥标准稠度需水量、凝结时间逐渐增加,强度逐渐降低;镍铁渣能显著降低水泥体系的水化热,降低水泥浆体孔隙率,提高浆体结构致密度;镍铁渣与矿粉复掺有助于水泥强度的发展,同时掺加镍铁渣与矿粉的水泥体系的安定性均合格.     

Prunella vulgaris Suppresses HG-Induced Vascular Inflammation via Nrf2/HO-1/eNOS Activation

Vascular inflammation is an important factor which can promote diabetic complications. In this study, the inhibitory effects of aqueous extract from Prunella vulgaris (APV) on high glucose (HG)-induced expression of cell adhesion molecules in human umbilical vein endothelial cells (HUVEC) are reported. APV decreased HG-induced expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin. APV also dose-dependently inhibited HG-induced adhesion of HL-60 monocytic cells. APV suppressed p65 NF-κB activation in HG-treated cells. APV significantly inhibited the formation of intracellular reactive oxygen species (ROS). HG-stimulated HUVEC secreted gelatinases, however, APV inhibited it. APV induced Akt phosphorylation as well as activation of heme oxygenase-1 (HO-1), eNOS, and nuclear factor E2-related factor 2 (Nrf2), which may protect vascular inflammation caused by HG. In conclusion, APV exerts anti-inflammatory effect via inhibition of ROS/NF-κB pathway by inducing HO-1 and eNOS expression mediated by Nrf2, thereby suggesting that Prunella vulgaris may be a possible therapeutic approach to the inhibition of diabetic vascular diseases.     

水性侧链含氟聚氨酯的制备与性能分析

为提高水性聚氨酯的综合性能,以侧链含氟聚醚多元醇、聚醚N210、异佛尔酮二异氰酸酯(IPDI)或4,4’-二环己基甲烷二异氰酸酯(HMDI)为主要原料,采用自乳化法合成了水性含氟聚氨酯分散体。研究了影响水性侧链含氟聚氨酯分散体的粒径、粒径分布、固含量、乳胶膜的热性能与耐酸碱性能的因素。结果表明:制备的侧链含氟聚氨酯分散体具有较小的粒径和较好的稳定性,其乳胶膜具有较好的耐化学品性和耐热性能。     

一种简单合成7-羟基-高异黄酮的催化方法

以间苯二酚和苯丙酸为原料,三氟化硼乙醚为催化剂合成了2',4'-二羟基二氢查尔酮(收率84%),再经过增碳成环得到7-羟基-高异黄酮(收率84%)。此法绿色简捷,生产成本较低。     

游离和固定化恶臭假单胞菌对含酚废水的处理

采用恶臭假单胞菌,以活性炭纤维为载体,以聚乙烯醇(PVA)为包埋剂制成固定化恶臭假单胞菌,对含酚废水的降解效果进行研究。与游离恶臭假单胞菌相比,固定化恶臭假单胞菌小球的运行周期长,对苯酚的降解效果好。讨论了外部环境因素包括苯酚的初始质量浓度、pH和温度对固定化恶臭假单胞菌降解苯酚效果的影响。结果表明,随着苯酚质量浓度的增加,固定化恶臭假单胞菌对苯酚具有良好的降解效果;当苯酚初始质量浓度大于200 mg/L时,固定化恶臭假单胞菌降解苯酚的效果远远优越于游离态的;固定化恶臭假单胞菌对高质量浓度的苯酚、pH和温度的变化表现出了较好的耐受力;当pH为7～9,温度在30～35℃,固定化恶臭假单胞菌对苯酚的降解效果达到93%。     

甲胺类制药废水放电等离子体处理的研究

采用介质阻挡放电来直接处理制药废水,设计了管式介质阻挡放电反应装置,研究了废液流量、放电电压、反应时间对甲胺、COD和BOD5去除率的影响,初步分析了主要有害物质降解过程。结果表明,该方法对甲胺、COD和BOD5的去除率均有较好的作用,提高了制药废水的可生化性,可作为该废水处理的生化预处理技术。     

Isothermal crystallization kinetics and subsequent melting behavior of β‐nucleated isotactic polypropylene/graphene oxide composites with different ordered structure

The effects of ordered structure on isothermal crystallization kinetics and subsequent melting behavior of β‐nucleated isotactic polypropylene/graphene oxide (iPP/GO) composites were studied using differential scanning calorimetry. The ordered structure status was controlled by tuning the fusion temperature (T_f). The results showed that depending on the variation of crystallization rate, the whole T_f range could be divided into three regions: Region I (T_f > 179 °C), Region II (170 °C ≤ T_f ≤ 179 °C) and Region III (T_f < 170 °C). As T_f decreased from Region I to Region III, the crystallization rate would increase substantially at two transition points, due to the variation of the ordered structure status. Calculation of Avrami exponent n indicated that the ordered structure induced the formation of two‐dimensional growing crystallites rather than three‐dimensional growing crystallites. Moreover, in the case of isothermal crystallization, the ordered structure effect (OSE) can also greatly increase the relative content of β‐phase (β_c). In Region II, OSE took place, resulting in evident increase of β_c, achieving 92.4% at maximum. The variation of the isothermal crystallization temperature (T_iso) had little influence on the T_f range (Region II) of the OSE. The higher T_f in Region II was more favorable for the formation of higher β_c. The ordered structure was favorable for the improvement of the nucleating efficiency of β‐nucleating agent (β‐NE), and was more effective for the improvement of lower β‐NE. © 2018 Society of Chemical Industry