海藻酸钠/羽毛角蛋白复合纤维的制备与性能

采用酸碱法在鸭毛中提取羽毛角蛋白（FK）,通过正交实验研究了FK提取的最佳条件。将FK与海藻酸钠（SA）进行共混,制备SA/FK复合溶液,测试了复合溶液的流变性。通过湿法纺丝制备SA/FK复合纤维,研究了复合纤维的基本性能并表征了复合纤维分子间氢键作用。结果表明:在最佳提取条件下（提取温度为60.0℃,提取时间为120.00 min,碱浓度为2.00wt%）,FK产率最高为45.75%。SA/FK复合溶液的表观黏度随剪切速率的增加而减小,随FK含量的增加呈现先增后减的趋势。FK的加入使分子间氢键作用增强。SA/FK复合纤维的力学断裂强度能够达到1.96 cN/dtex。SA与FK的复合破坏了原有分子的晶体结构,SA/FK复合纤维分子结构是以非晶态存在。SA/FK复合纤维的表面具有均匀的沟槽结构。      

鸡毛角蛋白海绵垫的制备及对丙酮的吸附性能

利用还原C法提取鸡毛中可溶性角蛋白后产生的残渣,通过简单的物理方法处理后制得致密多孔的角蛋白海绵材料.针对增塑剂对角蛋白海绵结构的影响进行了实验研究,结果发现,甘油质量分数4%时,其机械性能最佳,拉伸强度为5.04 MPa,断裂伸长率为8.60%,完整性和柔韧性最好.利用红外光谱仪对组成残渣的分子基团等进行了表征,以有机挥发性气体丙酮作为实验对象,考察孔隙率和吸附温度等因素对鸡毛角蛋白海绵垫吸附性能的影响.实验结果显示:当角蛋白海绵垫的孔隙率为82.59%、环境温度为25℃时,对丙酮挥发性气体24 h的吸附量为205.4 mg/g;吸附1个月后达到饱和状态,饱和吸附量达374.8 mg/g.充分利用废弃鸡毛这一资源,对于去除环境中气体污染物具有一定的应用潜力.     

An investigation into a falling film type cooling tower

A model for a falling film type cooling tower has been developed to investigate the effect of tower parameters as well as the effect of liquid-side thermal resistance on the tower performance. The energy equation is used to determine the temperature distribution across the liquid film. The heat and mass transfer processes between the liquid film and air bulk are described using three ordinary differential equations. The energy equation was solved using a finite difference Crank-Nicolson scheme. The heat and mass transfer equations were solved using the Runge-Kutta method. The results obtained show that an increase in tower characteristic KaV/L under the same conditions improves the tower performance. The converse is true in the case of increased water to air mass flowrate ratio, L/G. The Lewis number, Le, shows no significant effect on the tower performance. The effect of tower parameters as well as the water inlet temperature on the liquidside Nusselt number and the tower effectiveness was also studied. The results show very insignificant changes in Nusselt number, whereas the effectiveness increases with increasing KaV/L and reduces with L/G, but very insignificant changes occur with Le. The present model is also compared with Merkel's equation. Under the same conditions and with Le equal to unity, the results of the Merkel equation shows a smaller approach than that obtained by the present model.     

表面活性剂改性的大孔径介孔炭对电极染料敏化太阳电池(英文)

以大孔径的介孔炭(MC)为催化层材料经低温热处理构建出炭对电极,着重探讨了在炭浆料中添加Triton X100对其组装的染料敏化太阳电池(DSCs)光电性能的影响,并引入分形维数(DF)用于定量评估炭膜形貌的差异。结果表明,当炭浆料中Triton X100的含量增加到0.1 mL(相应MC含量为0.6 g)时,DSCs的光电转换效率增加至5.65%,其值比活性炭对电极DSCs高46.5%,且达到Pt对电极DSCs的95.4%。Triton X100改性的介孔炭对电极的高性能归功于高品质的炭膜和介孔炭本身合理的孔结构(如大尺寸孔径和大比表面积等)。相对于未添加Triton X100的纯介孔炭对电极,Triton X100改性的介孔炭对电极具有分布更均匀的炭膜和更小的分形维数,是对电极欧姆串阻减小及相应器件效率改善的一个重要因素。     

Environmental aspects and economic evaluation of new green hydrolysis method for waste feather processing

Clean Technologies and Environmental Policy - In recent years, an increase in the chicken meat process industry has been growing quickly, which brings a large amount of difficult to process waste,...     

Particles from bird feather: A novel application of an ionic liquid and waste resource

The dissolution and regeneration of the waste chicken feathers in an ionic liquid of 1-butyl-3-methylimi-dazolium chloride ([BMIM]Cl) were demonstrated for preparing chicken feather based particles. The structure and properties of the regenerated chicken feathers were investigated by FT-IR, XRD, SEM, BET and water contact angle. The crystallinity of the regenerated chicken feathers was decreased, and the content of β-sheet was 31.71%, which was clearly lower than the raw feather (47.19%). The surface property of chicken feather changed from hydrophobicity to hydrophilicity after regenerated from [BMIM]Cl as indicated by the change of the water contact angle from 138 to 76°. The chicken feather particles regenerated from [BMIM]Cl showed an excellent efficiency (63.5–87.7%) for removing Cr(VI) ions in wastewater at the concentrations from 2 to 80 ppm. The Freundlich constant (k_F) for the adsorption of Cr(VI) ion by the particles of the regenerated chicken feather was four times larger than that of the raw chicken feather, the possible reason is the hydrophilic groups such as amino and carboxyl groups were tend to self-assemble towards surface when the dissolved CF were regenerated by water, amino group will partly hydrate to cationic amino and Cr(VI) ion occurs as an anion in the aqueous phase, so the cationic amino will adsorb the anionic Cr(VI) ion onto the RCF particles through electrostatic attraction. This work demonstrated a new application of the ionic liquid for dissolving chicken feather and a renewable application of waste chicken feather for removing Cr(VI) ion in water.     

Plasmonic-metal nanostructures for efficient conversion of solar to chemical energy

Recent years have seen a renewed interest in the harvesting and conversion of solar energy. Among various technologies, the direct conversion of solar to chemical energy using photocatalysts has received significant attention. Although heterogeneous photocatalysts are almost exclusively semiconductors, it has been demonstrated recently that plasmonic nanostructures of noble metals (mainly silver and gold) also show significant promise. Here we review recent progress in using plasmonic metallic nanostructures in the field of photocatalysis. We focus on plasmon-enhanced water splitting on composite photocatalysts containing semiconductor and plasmonic-metal building blocks, and recently reported plasmon-mediated photocatalytic reactions on plasmonic nanostructures of noble metals. We also discuss the areas where major advancements are needed to move the field of plasmon-mediated photocatalysis forward.     

Highly efficient broadband conversion of light polarization by composite retarders

Driving on an analogy with the technique of composite pulses in quantum physics, we propose highly efficient broadband polarization converters composed of sequences of ordinary retarders rotated at specific angles with respect to their fast-polarization axes.     

An efficient approach to converting three-dimensional image data into highly accurate computational models

Image-based meshing is opening up exciting new possibilities for the application of computational continuum mechanics methods (finite-element and computational fluid dynamics) to a wide range of biomechanical and biomedical problems that were previously intractable owing to the difficulty in obtaining suitably realistic models. Innovative surface and volume mesh generation techniques have recently been developed, which convert three-dimensional imaging data, as obtained from magnetic resonance imaging, computed tomography, micro-CT and ultrasound, for example, directly into meshes suitable for use in physics-based simulations. These techniques have several key advantages, including the ability to robustly generate meshes for topologies of arbitrary complexity (such as bioscaffolds or composite micro-architectures) and with any number of constituent materials (multi-part modelling), providing meshes in which the geometric accuracy of mesh domains is only dependent on the image accuracy (image-based accuracy) and the ability for certain problems to model material inhomogeneity by assigning the properties based on image signal strength. Commonly used mesh generation techniques will be compared with the proposed enhanced volumetric marching cubes (EVoMaCs) approach and some issues specific to simulations based on three-dimensional image data will be discussed. A number of case studies will be presented to illustrate how these techniques can be used effectively across a wide range of problems from characterization of micro-scaffolds through to head impact modelling.     

Hydrothermal conversion of biomass into acetic acid

Hydrothermal process is one of the most promising processes for the conversion of biomass waste into resources among the several biomass conversion processes, because water of high temperature and high pressure has remarkable properties as a reaction medium. This paper described advances in our research involving overall reaction pathways for acetic acid production from biomass, mainly including (1) acetic acid production by controlling pathways of hydrothermal reaction, (2) acid-base behavior of water in the subcritical region and (3) effect of lignin on the acetic acid production in WO of lignocellulosic biomass.     

Catalytic conversion of waste particle board to bio-oil using nanoporous catalyst

The catalytic pyrolysis of waste wood including the particle board was examined by pyrolysis gas chromatography/mass spectrometry (Py-GC/MS) to produce bio-oil. Three different catalysts with a nanoporous structure, Al-MCM-48, Meso-MFI, and Pt-Meso-MFI, were used and their performances were compared. When MCM-48 was used, the quality of the bio-oil product was better than that prepared by non-catalytic pyrolysis but the improvement was limited due to its weak acid sites. On the other hand, Meso-MFI, which has both an MFI structure and strong acid sites, exhibited much better cracking ability and higher selectivity for aromatics. Moreover, Pt-impregnation on Meso-MFI resulted in an even higher selectivity for aromatics and phenolics, which are important raw materials in various petroleum chemical processes. Keywords: Catalytic Pyrolysis, Py-GC/MS, Waste Particle Board, AI-MCM-48, Meso-MFI,     

An investigation into the links between island patterns and the mechanisms of thin film deposition

Statistical analysis of pictures of island arrays grown on a substrate during thin-film deposition can yield useful information to the experimentalist such as the shape of the island size distribution. We present an investigation of how this type of information can in turn be used to identify the most important mechanisms governing the growth process. We have used a computational model based on deposition, diffusion, and aggregation (DDA) for the following situations: (1) normal DDA where the island size distributions scale with coverage and are distinguished by the critical island size; (2) DDA plus monomer evaporation, which yields scaling island size distributions that lie between a powerlaw and the normal DDA results depending on the evaporation rate; (3) DDA with a finite probability of islands absorbing monomers, which yields similar distributions to case (2) but crucially does not display the scaling with coverage; and (4) DDA with mobile islands where an even more dramatic departure from scaling is observed.     

Reaction mechanisms in the geopolymeric conversion of inorganic waste to useful products

High-performance materials for construction, waste immobilisation and an ever-growing range of niche applications are produced by the reaction sequence known as 'geopolymerisation'. In this process, an alkaline activating solution reacts with a solid aluminosilicate source, with solidification possible within minutes and very rapid early strength development. Geopolymers have been observed to display remarkable chemical and thermal stability, but due to their largely X-ray amorphous nature have only recently been accurately characterised. It has previously been shown that both fly ash and ground granulated blast furnace slag are highly effective as solid constituents of geopolymer reaction slurries, providing readily soluble alumina and silica that undergo a dissolution-reorientation-solidification process to form a geopolymeric material. Here a conceptual model for geopolymerisation is presented, allowing elucidation of the individual mechanistic steps involved in this complex and rapid process. The model is based on the reactions known to occur in the weathering of aluminosilicate minerals under alkaline conditions, which occur in a highly accelerated manner under the conditions required for geopolymerisation. Transformation of the waste materials to the mixture of gel and nanocrystalline/semicrystalline phases comprising the geopolymeric product is described. Presence of calcium in the solid waste materials affects the process of geopolymerisation by providing extra nucleation sites for precipitation of dissolved species, which may be used to tailor setting times and material properties if desired. Application of geopolymer technology in remediation of toxic or radioactive contaminants will depend on the ability to analyse and predict long-term durability and stability based on initial mix formulation. The model presented here provides a framework by which this will be made possible.     

The conversion technology of fly ash into zeolites

This paper presents a sub-pilot scale process of synthesis of Na-P1 zeolite from the coal fly ash. After establishing the appropriate synthesis conditions (20 kg of fly ash, 12 kg of NaOH, 90 dm³ of water, the reaction temperature: 80 °C and reaction time: 36 h), the high-purity (81 wt%) Na-P1 zeolite product was obtained. Its chemical, mineralogical, and textural properties were determined (by means of XRD, XRF, SEM–EDS and ASAP 2020). The synthesized material has a specific BET surface area (88 m²/g) c.a. six times higher than the fly ash from which it has been derived (15 m²/g). The pore-size distribution indicates a mesoporous character of the obtained zeolite, with the following pores size contents: micropores (2.76 %), mesopores (61.81 %), and macropores (35.43 %). The presented technological/production line is fully automated and allows to regulate the conditions of the synthesis process, therefore different types of zeolite materials (including: Na-X, Linde-A, and Na-P1) can be obtained using the same equipment.     

建筑垃圾界面膜化对水泥砂浆强度的影响

本文设置了不同的再生集料替代率,和不同的处理方式,并对试验结果进行了对比和分析,研究了垃圾界面膜化对砂浆强度的影响。结果表明,在取代率相同的情况下,再生骨料经过处理以后其强度最大增加25％,而且随着垃圾砂掺量的增加,砂浆强度呈现出总体下降的趋势。     

双级永磁同步变频离心机余热采暖应用

本项目利用循环化工基地的工艺循环水输送至分布首站,换出一次水,通过一次管网输送到用户侧,由双级永磁同步变频离心式热泵机组对区域住宅实现供热,从而实现了对工业余热的有效利用.     

Thermal and plasma-chemical conversion of cadmium into α-CdS

This report deals with investigations of the thermal and plasma-chemical conversion of cadmium into α-CdS in order to produce large CdS grains. Thermal conversion in an atmosphere containing H₂S led to CdS crystallites about 10 μm in size in cadmium layers of thickness 3 μm. Plasma-chemical conversion was only effective in the surface of the cadmium layer had already been transformed into CdS by thermal conversion. It was mainly locally effective, i.e. the stoichiometry in the CdS layers produced by thermal conversion could be altered, as demonstrated by the change in the sheet resistance. The combination of thermal and plasma-chemical conversion enables us to transform the upper part of a cadmium layer into α-CdS and to control the resistance in a well-defined manner. Since the lower part of the layer remains fundamentally metallic, the adhesion to the substrate is guaranteed, and at the same time the metallic part of the layer can be used as a rear electrode.     

Thermal conversion of bundled carbon nanotubes into graphitic ribbons

High temperature heat treatment (HTT) of bundled single-walled carbon nanotubes (SWNTs) in vacuum ( approximately 10(-5) Torr) has been found to lead to the formation of two types of graphitic nanoribbons (GNRs), as observed by high-resolution transmission electron microscopy. Purified SWNT bundles were first found to follow two evolutionary steps, as reported previously, that is, tube coalescence (HTT approximately 1400 degrees C) and then massive bond rearrangement (HTT approximately 1600 degrees C), leading to the formation of bundled multiwall nanotubes (MWNTs) with 3-12 shells. At HTT > 1800 degrees C, we find that these MWNTs collapse into multishell GNRs. The first type of GNR we observed is driven by the collapse of diameter-doubled single-wall nanotubes, and their production is terminated at HTT approximately 1600 degrees C when the MWNTs also start to form. We propose that the collapse is driven by van der Waals forces between adjacent tubes in the same bundle. For HTT > 2000 degrees C, the heat-treated material is found to be almost completely in the multishell GNR form.