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For an effective optimization of pulp thermoforming and of the moulded pulp products manufactured by this process, a full understanding of the process physics combined with full knowledge of the pressing equipment is necessary. For this reason, in this Addendum, we clarify how the process parameters “Holding time,” “Vacuum time,” “Cycle time,” and “Temperature” were interpreted and subsequently defined for the analysis of the process and product‐related outputs of the thermoforming experiments. 相似文献
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以太阳纸业备料车间木片筛选碎料(筛余物)为原料,对其烧碱法半化学制浆的实验室工艺和生产试验进行了研究。结果表明,筛余物采用半化学法制浆可获得较高得率和环压强度的纸浆,且用碱量对纸浆性能有显著影响。相对8%NaOH (相对于绝干原料)化学预处理,采用14%NaOH化学预处理结合两段浆浓22%的高浓磨浆工艺,所制半化学浆抄造浆张的裂断长和环压指数分别达2.89 km和9.76 N·m/g,是前者的1.9倍和1.2倍,而且优于现用国内OCC废纸浆抄造浆张;生产试验得到的浆张性能指标与实验室相吻合,其中紧度和环压强度分别达到GB/T 13023—2008瓦楞芯(原)纸AA级和A级优等品要求。 相似文献
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The aim of the study is to investigate the optimum dyeing conditions for wool and cotton fabrics with the nettle (Urtica dioica L.) extract. For this purpose, the leaves of the nettle were extracted with distilled water by using Soxhlet apparatus. Wool and cotton fabrics were pretreated with artificial animal urine system (AAUS) including NH3 (3%, v/v), CaC2O4 (3%, m/v), and urea (3%, m/v) before dyeing processes in order to improve the fastness properties of the dyed samples. The best dyeing conditions were evaluated in terms of color strength. The results reveal that the nettle leaves shall probably be an important raw material especially for dyeing of wool fibers. 相似文献
6.
Near- and short-wave IR emission spectra of printed cotton/nylon blend fabrics coated with inorganic compounds in order to tune their diffuse reflectance behavior to the ones with woodland and desert backgrounds are investigated. In this regard, cotton/nylon blend fabrics printed with a four-color digital pattern were used as the substrate, and different concentrations of zirconium and cerium dioxide (ZrO2 and CeO2) with and without citric acid as a cross-linker were loaded on these fabrics using the pad-dry-cure method. The diffuse reflectance of the coated fabrics with various concentrations of nanoparticles and a cross-linker was first measured by near-infrared (NIR) diffuse reflectance spectroscopy (DRS). Then, fabrics with an optimum concentration of nanoparticles and appropriate reflectivity profiles similar to woodland and desert were investigated by field emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), washing, and rubbing fastness properties. In general, NIR and short-wave infrared (SWIR) reflectance of fabrics coated with ZrO2 and CeO2 nanoparticles in range of 1% to 1.5% (w/v [%]) was suitable for matching with different environments. According to the findings obtained from the durability test, it was concluded that the washing fastness of the treated fabrics with CeO2 nanoparticles was excellent in both environments. FE-SEM images of the treated fabrics containing ZrO2 and CeO2 indicated that the presence of nanoparticles on the surface of fabrics in woodland patterns was greater than the desert ones. However, the coated fabrics with CeO2 and citric acid in the woodland pattern have shown better dispersion with a mean particle size of 30 to 60 nm. 相似文献
7.
This study evaluated the shear bond strength (SBS) and internal marginal adaptation of pulp‐capping materials to dentin. Flat occlusal deep dentin surfaces were produced and randomly assigned to two groups (sound or artificial caries‐affected dentin). The specimens in each group were assigned to one of seven subgroups according to the materials used: Biodentine, Theracal LC, Ultra‐Blend plus, Calcimol LC, ApaCal ART, EQUIA Forte, and Ionoseal. Buildups (3‐mm inner diameter and 2‐mm deep) were made over the dentin surfaces. The bonded specimens were tested under shear forces at a crosshead speed of 0.8 mm/min and fracture modes were determined using a stereomicroscope at 25× magnification. The materials were applied to the pulp floor of prepared Class I cavities and then the cavities were restored with composite resin. Restored molar teeth were subjected to 5,000 thermocycles and sectioned in a bucco–lingual direction. Resin replicas were made to determine the adaptation at the pulp floor with scanning electron microscopy. Significant differences were determined among both bond strengths and gap formations of the materials. EQUIA Forte applied to both dentin substrates had a significantly higher SBS than the other materials. The bond strength of each material was not influenced by the dentin condition. Biodentine (3.03%), EQUIA Forte (7.83%), and Theracal LC (13.37%) had lower gap formations compared to other materials but were not significantly different from each other. 相似文献
8.
Blend fabrics of cotton and polyester are widely used in apparel, but high flammability becomes a major obstacle for applications of those fabrics in fire protective clothing. The objective of this research was to investigate the flame retardant finishing of a 50/50 polyester/cotton blend fabric. It was discovered previously that N,N′‐dimethyloldihydroxyethyleneurea (DMDHEU) was able to bond a hydroxy‐functional organophosphorus oligomer (HFPO) onto 50/50 nylon/cotton blend fabrics. In this research, the HFPO/DMDHEU system was applied to a 50/50 polyester/cotton twill fabric. The polyester/cotton fabric treated with 36% HFPO and 10% DMDHEU achieved char length of 165 mm after 20 laundering cycles. The laundering durability of the treated fabric was attributed to the formation of polymeric cross‐linked networks. The HFPO/DMDHEU system significantly reduced peak heat release rate (PHRR) of cotton on the treated polyester/cotton blend fabric, but its effects on polyester were marginal. HFPO/DMDHEU reduced PHRR of both nylon and cotton on the treated nylon/cotton fabric. It was also discovered that the nitrogen of DMDHEU was synergistic to enhance the flame retardant performance of HFPO on the polyester/cotton fabric. 相似文献
9.
The pre-hydrolysis liquor (PHL) of the kraft-based dissolving pulp production process is currently sent to the recovery boiler and incinerated. However, PHL contains about 5–8% lignocelluloses that can be utilized in the production of value-added chemicals. In this study, a process for producing xylitol from hemicelluloses in PHL is developed. This process involves several acidification, neutralization, adsorption (along with reactivation) and evaporation stages. The mass balance indicates that 533 kg/h xylitol (with 99% purity), 187 kg/h lignin, 806 kg/h basic ferric acetate, and 1600 kg/h gypsum can be produced from 41,670 kg/h PHL. The energy balance shows that the evaporators are the largest consumers of energy, while the reactivation kiln, acidification, neutralization, and precipitation processes generate some heat. Overall, 41% conversion of xylose to xylitol is achieved. 相似文献
10.
Bianca Moreira Barbosa Jorge Luiz Colodette Dalton Longue Júnior Fernando José Borges Gomes Daniela Correia Martino 《木材化学与工艺学杂志》2014,34(3):178-190
This study focused on the production of furfural from agricultural and industrial biomass residues by a hydrodistillation process. Corncobs, sugarcane bagasse, and eucalypt wood were treated with sulfuric, hydrochloric, and phosphoric acids as catalysts, with different acid concentrations (1.5 to 5.2 mol.L ?1). In addition, the eucalypt liquor from the auto-hydrolysis, kraft-dissolving pulp production process was also investigated as a source of furfural, using sulfuric and hydrochloric acids as a catalyst (0.9 and 3.9 mol.L ?1) . Furfural yields of 30.2, 25.8, and 13.9% were achieved for corncob, sugarcane bagasse, and eucalypt wood, respectively, on the basis of biomass dry weight. The efficiency of conversion from pentose to furfural using eucalypt liquor from the auto-hydrolysis kraft process was 71.5% using HCl 3.9 mol.L ?1 . Due to the presence of a high amount of pentose, corncob produced the highest amount of furfural, followed by sugarcane bagasse and then eucalypt wood. 相似文献