硼酸锌协效二乙基次膦酸铝阻燃PA6

采用硼酸锌(ZB)与二乙基次膦酸铝(ADP)协同阻燃聚酰胺6(PA6).对其阻燃性能和力学性能进行了探讨,并运用垂直燃烧、极限氧指数、锥形量热、热失重分析、扫描电子显微镜以及拉曼光谱对阻燃机理进行了探究.结果表明,ZB作为协效剂,与ADP的协同阻燃效果显著;当在PA6中添加1.5％(质量分数,下同)ZB和8.5％ADP...     

Characterizing the catalyst fluidization with field synergy to improve the amine absorption for CO_2 capture

There are great interests to capture the CO_2 to control the greenhouse gas emission. Amine absorption of CO_2 is being taken as an effective way to capture CO_2 in industry. However, the amine absorption of CO_2 is cost-ineffective due to great energy consumption and solution consumption. In order to reduce the capture cost, catalyst fluidization is proposed here to intensify the mass transfer and heat transfer. Catalyst fluidization with field synergy and DFT model is developed by incorporating the effects of catalyst reaction kinetics, drag force and multi-field into the mass transfer, heat transfer, fluid flow and catalyst collision. Experiments with an improved distributor are performed well to validate the model. The reaction kinetics is determined by the DFT simulation and experiment. The mass transfer coefficient in the fluidized reactor is identified as 17% higher than the conventional packed reactor. With the field synergy of catalyst fluidization, the energy consumption for CO_2 desorption is reduced by 9%. Stepwise operation and inclination reactor are used to improve catalyst fluidization process.     

Biopolymers interaction elaborating using viscoelastic relaxation spectra,network parameters,and thermodynamic properties

Herein, oscillatory rheological measurements were performed to study the interaction behavior of xanthan gum‐sage seed gum blends at different ratios (SSG‐XG: 1–0, 3–1, 1–1, 1–3, 0–1), from the dynamic viscosity behavior, relaxation spectrum, fracture properties, network parameters, and thermodynamic points of view at the temperature range of 10–90°C. Then, the coefficient of the interaction of four parameters, which were obtained from the clustering technique and Han curves, were used to investigate the interaction behavior quantitatively. At 90°C, SSG showed 2.01 extent of loss modulus overshoot, which was the highest value among different gum dispersions at different temperatures, while XG showed strain softening behavior. At 10 and 90°C, SSG and 1–1 SSG‐XG showed the highest spreadability reflected by the slope of loss tangent after flow point stress (tan δ_AF ) of 0.52 and 0.40, respectively. The high values of ψ parameter, which represented the Gibbs free energy change, of both 1–3 and 3–1 SSG‐XG blends and the lowest entropy value of 1–3 SSG‐XG, suggested that the role of entropy change in incompatibility behavior of 1–3 SSG‐XG was higher than that of 3–1 SSG‐XG blend. With the increase in temperature from 10 to 70°C, the XG Euclidean distance from SSG decreased, while it increased from 70 to 90°C and showed the highest Euclidean distance with XG at 10°C (3.92) and 90°C (4.05). Interaction coefficients and Han curves results showed that all blends were incompatible with the lowest antagonistic behavior for 1–1 SSG‐XG dispersion at 50°C. Often, a mixture of hydrocolloids, especially xanthan gum and a galactomannan, are employed in processed foods to modify their rheological properties and cut the cost. The synergistic/non‐synergistic effect of biopolymers mixture, which is invaluable from the practical and economical points of view, seems to be mainly induced by their thermodynamic status of interaction. Our former study showed that the thermodynamic indices of mixing could be probed by mechanical parameters. On the other hands, we found that the mechanical properties of materials are highly temperature dependent. Therefore, in this study, to better investigate the effect of temperature on the biopolymers interaction, first we classified all the thermodynamic and mechanical properties (relaxation spectrum, fracture properties, and network parameters) of hydrocolloids into four classes, then one parameter was selected randomly from each class. The selected parameters were employed to investigate the synergistic/non‐synergistic effect at all temperature ranges by determining the interaction coefficient and decide on the best interaction temperature.     

黄连、连翘对几种常见食品污染菌的体外协同抑菌效果

测定了黄连、连翘对6种常见食品污染菌的抑制效果并对其协同抑菌配方进行了优化。通过测定抑菌圈直径和最小抑菌浓度2个指标判定黄连、连翘对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌、藤黄微球菌、汉逊酵母和黑曲霉的抑菌能力大小,并利用FIC值判定黄连、连翘的体外联合抑菌能力。以藤黄微球菌为例,通过配方试验对黄连-连翘体外抑菌协同效应最佳配比进行优化。结果显示,黄连、连翘配伍后对6种菌的抑制能力均有一定的协同或相加效果;对藤黄微球菌的体外联合抑菌配方试验得出黄连、连翘的最佳配比为4.523∶5.477,此时具有最大的协同作用。     

Flow visualization of Rayleigh–Bénard convection for cubical cavity

Natural convective flow of air inside the cubical cavity is investigated numerically. The temperature of the bottom wall is kept higher than that of top cold wall, and other four walls are assumed to be adiabatic. Attention has been paid to the convective discretization schemes, like upwind, QUICK, total variation diminishing, normalized variable diagram (NVD) schemes that are compared with respect to accuracy. The output is validated with respect to the results available in the literature. A parallel computing message passing interface code is adapted to run the simulations. From the results, it is observed that the NVD scheme gives better results among all the employed convective discretization schemes irrespective of the mesh structure. Thus, in this article, self filtered central differencing which is a family of NVD, is used. From the enormous output data, along with the streamlines, contours of isotherms, the new technique of energy pathlines, and field synergy are used to visualize the fluid flow and heat transfer mechanism arising in the system in the range of Ra from 10³ to 10⁶. Free energy streamlines are observed with small Ra, whereas trapped energy streamlines are observed with high Ra. When Ra increases, synergy angle increases and implies that the synergy between the velocity vector and temperature gradient gets reduced and leads to increasing values of average Nusselt number (Nu).     

新型建筑工业化与BIM 技术的协同关系分析

本文主要以新型建筑工业化与BIM技术的协同关系分析为重点阐述,结合当下建筑工业化和BIM技术两者关系、新型建筑工业要点、BIM技术基本作用和BIM技术和新型建筑工业化协同关系为主要依据,从能够创建关系矩阵、两者协同关系解释这几方面进行深入探索与研究,其目的在于加强BIM技术在新型建筑工业化中的运作效率。     

多流多科目实时数据处理算法的设计与实现

随着飞行试验测试技术的快速发展,单架次需要处理的试飞科目越来越多,而多科目处理参数分布在不同的网络流中,这对机载实时数据处理的效率带来严峻的挑战。利用“合并-处理-分流”的方法,设计一种多流多科目网络数据实时处理算法。该算法将多科目处理参数按照参数名、采样率等信息进行整合形成合并参数列表；在实时处理时根据合并参数信息实时处理多网络流中的数据,并将处理结果存储在数据缓存中；最后将多科目数据进行分流即可得到处理结果。测试结果表明,该算法可实际应用于多流多科目数据处理中,大幅提高实时处理的效率,同时可以得到准确的数据处理结果。     

One-pot synthesis of the highly efficient bifunctional Ni-SAPO-11 catalyst

Hydroisomerization of linear alkanes to branched isomers is an important petrochemical process for production of gasoline with high octane number.Non-noble metal bifunctional catalysts used in this process always suffer from low metal dispersion and poor metal-acid synergy.Herein,a facile one-pot synthesis method was used to simultaneously regulate metal particle sizes and acidity of the Ni-SAPO-11 hydroisomerization catalyst.The physicochemical properties are investigated using XANES,EXAFS,TEM/STEM,FT-1R,XPS,UV-vis and NH3-TPD.Apart from the highly dispersed nickel nanoparticles with an average diameter of 8 nm,the framework Ni2+ions are generated via substituting framework Al3+ions of the SAPO-11.The formed NiP-OH structures have lower deprotonation energy(DPE)than the SiAl-OH ones,contributing more and stronger acid sites to the Ni-SAPO-11 catalyst.The great metal-acid synergy including high metal to acid sites ratio(nNi/nA)and close intimacy is obtained for the Ni-SAPO-11 catalyst.The Ni-SAPO-11 catalyst outperforms the counterpart prepared by the impregnation method and exhibits comparable activity and isomers selectivity to the Pt/SAPO-11 catalyst in the n-hexane hydroisomerization.