Optimization issues of the broke management system in papermaking

This paper presents an optimization strategy for the design and operation of a broke management system in a papermaking process. A stochastic model based on a two-state Markov process is presented for the broke system and a multiobjective and bi-level stochastic optimization model is developed featuring (i) a multiobjective operational subproblem for the optimization of the broke dosage and (ii) a multiobjective design problem formulation. An efficient optimization strategy is proposed for the operational subproblem along with a simulation based Pareto optimal solution for the design problem, and illustrated with a detailed case study.     

Bacterial nanocellulose‐reinforced arabinoxylan films

There is an increasing interest in substituting today's films for food packaging applications with films based on renewable resources. For this purpose, rye arabinoxylans, unmodified and enzymatically debranched, were studied for the preparation of neat films and composite films reinforced with bacterial cellulose (BC). Mixing in a homogenizer produced optically transparent, uniform films. Physical and mechanical characteristics of such films are here reported. Debranching of the arabinoxylan caused an increase in its crystallinity of 20%. Debranching as well as reinforcement with BC resulted in a decrease of the moisture sorption of the films. The debranching also resulted in a reduced breaking strain while the reinforcement with BC increased stiffness and strength of the films. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Isomerization of Alpha-pinene Over Acid Treated Natural Zeolite

In this study, isomerization of α-pinene was studied over several acid-treated natural zeolite catalysts rich in clinoptilolite. Zeolite samples were contacted with HCl at different concentrations at 30°C or at 60°C for 3 and 24 hours and tested in isomerization reaction of alpha-pinene. The catalysts prepared were characterized by XRD, nitrogen adsorption, and acidity studies. Acidity strength and the distribution of Lewis and Brönsted acid sites of the catalysts were determined, and their catalytic activities in α-pinene isomerization and selectivities to main reaction products, camphene and limonene, were investigated. Acid treatment improved the selectivity of catalyst samples to camphene, decreasing the selectivity to limonene, probably forcing limonene to secondary reactions at high conversions.

The kinetics of α-pinene consumption was described by first-order kinetics. Two kinetic models were tested for the reaction mechanism and one model was found to give a good correlation between the theoretical and experimental data. In the models, the key intermediate was the pinylcarbonium ion, which was formed irreversibly from α-pinene.

Number and distribution of Lewis and Brönsted acid sites affect the formation of bicyclic and monocyclic products.     

“江蚁”群体工作幸福感的形成机理与提升策略

分析现阶段武汉＂蚁族＂群体（简称＂江蚁＂）生活就业和工作幸福感状况,探讨＂江蚁＂工作幸福感的影响因素、形成机理和提升策略,以期改善＂江蚁＂的生活就业状况,促进武汉市城市和谐发展,提高武汉市企业人力资源管理水平。     

Composition and microstructure of Na0.5Bi0.5TiO3 ceramics with excess Bi

In the present work, Na_0.5Bi_0.5TiO₃ (NBT) ceramics with the addition of excess Bi in two different ways – before calcination and before sintering – are considered, revealing how the excess Bi affects their microstructure and chemical content. Average grain size is seen to decrease, with the grain size distribution becoming less diffused at higher excess Bi concentrations. The reason for such a feature is the shift of the sintering temperature region where the abnormal grain growth starts to contribute towards higher temperatures. The influence of excess Bi is more pronounced in the case if it is added before calcination. It was discovered that a small amount of excess Bi helps to prevent the formation of Bi-deficient inclusions. While, high concentrations of excess Bi induce the formation of Bi-rich inclusions – most probably Na_0.5Bi_4.5Ti₄O₁₅. Possible mechanisms of formation of both types of inclusions are discussed in detail. Instead of Bi over-stoichiometry, elevated Na content and slightly lower O content were detected in the matrix grains of the sintered NBT ceramics prepared with excess Bi. These deviations increase upon increasing the added excess Bi concentration. The presence of another, Na-rich phase, is assumed, which could not be detected by X-ray diffraction or by energy-dispersive X-ray analysis.     

N‐Acylethanolamines Bind to SIRT6

Sirtuin 6 (SIRT6) is an NAD+‐dependent histone deacetylase enzyme that is involved in multiple molecular pathways related to aging. Initially, it was reported that SIRT6 selectively deacetylated H3K9Ac and H3K56Ac; however, it has more recently been shown to preferentially hydrolyze long‐chain fatty acyl groups over acetyl groups in vitro. Subsequently, fatty acids were demonstrated to increase the catalytic activity of SIRT6. In this study, we investigated whether a series of N‐acylethanolamines (NAEs), quercetin, and luteolin could regulate SIRT6 activity. NAEs increased SIRT6 activity, with oleoylethanolamide having the strongest activity (EC₅₀ value of 3.1 μm ). Quercetin and luteolin were demonstrated to have dual functionality with respect to SIRT6 activity; namely, they inhibited SIRT6 activity with IC₅₀ values of 24 and 2 μm , respectively, and stimulated SIRT6 activity more than sixfold (EC₅₀ values of 990 and 270 μm , respectively).     

Effective method for dispersing SiO2 nanoparticles into polyethylene

The nonisothermal crystallization behavior and kinetics of polytetrafluoroethylene (PTFE) and PTFE/solid glass microsphere (SGM) composites were investigated with differential scanning calorimetry at various cooling rates (?'s). Three methods, namely, the Jeziorny, Ozawa and Mo methods, were used to describe the nonisothermal crystallization process. The results show that the peak temperature, crystallinity (X_c), and crystallization half‐time were strongly dependent on the content of SGMs and ?. The SGMs in the PTFE/SGM composites exhibited a higher nucleation activity. The nonisothermal crystallization kinetics of PTFE and the PTFE/SGM composites was analyzed successfully with the Jeziorny and Mo methods; however, the Ozawa equation was invalid for the nonisothermal crystallization process. The crystallization activation energy determined with the Kissinger equation was remarkably lower when a small amount of SGMs (5%) was added and then gradually increased and finally became slightly lower than that of pure PTFE as the content of SGMs increased up to 25% in the composites. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Dyeing and deodorizing properties of cotton,silk, wool fabrics dyed with Amur Corktree,Dryopteris crassirhizoma,Chrysanthemum boreale,Artemisia extracts

This study used four kinds of natural colorant solutions extracted from Amur Corktree, Dryopteris crassirhizoma, Chrysanthemum boreale, Artemisia using water at 90°C for 90 min with a liquor ratio (solid natural colorant material/solvent water, weight ratio) of 1/10. The dyeing, color fastness, deodorizing properties of cotton, silk, wool fabrics dyed with natural colorant extracts were compared. These properties were found to be significantly dependent on the extract concentration, colorant structure, fabric type. Color fastness (light, water, perspiration fastness) ranged between second and fifth grades and deodorizing performance of fabrics dyed with various natural colorant extracts between 34 and 99%. It is worth noting that the use of natural colorants notably enhanced the deodorizing performance. Wool fabrics showed the highest performance increase at 98–99%, followed by silk and cotton. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010