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Colour Reflectance Investigation of Decolourized Sulfur Dyed Cotton Knitted Fabric via Ozone Plasma Treatment
Get PDFOzone plasma treatment is accessible to be applied on shading adjustment and colour fading because of the capacity of ozone production. It is a green process that treats dyed cotton fabric under dry condition so as to avoid chemical pollutants. This study means to explore colour reflectance of decolourized sulfur dyed cotton texture using ozone plasma treatment. Sulfur dyed cotton textures with various colour depths (0.5%, 1.5%, 2.5%) were set up to be treated different plasma parameters, including ozone air concentrations (10%, 30%, 50%, 70%), water contents in terms of weight percentage (35%, 45%) of fabric and ozone air plasma treatment periods (10 mins, 20 mins, 30 mins). The colour fading result is assessed by the colour reflectance in percentage (R%) utilizing spectrophotometer under CIE standard illuminant D65. The valid colour fading based on high percentage of reflectance was demonstrated from plasma treatment under higher ozone air concentration (50% and 70% ozone in air) and longer time length of plasma treatment (20 mins and 30 mins). The level of water content contained in the cotton fabrics is appeared to have noteworthy relationship with the degree of decolourization
Design and installation of post-installed reinforcements: A state-of-the-art review
Get PDFPost-installed reinforcement (PIR) helps facilitate retrofitting works, mitigate misplaced reinforcement problems, as well as support newly cast concrete members such as modular integrated construction. However, it has not been holistically addressed in major international reinforced concrete (RC) design codes. Nonetheless, based on established design philosophy and associated failure modes, the cast-in reinforcement design method in RC can be extended to design qualified PIR systems. The qualification of PIR system can be referenced to AC 308 (2016), European Assessment Document (EAD) 330087 (2018) and EAD 330499 (2017) in the US and Europe, respectively. In Hong Kong, PIR is conservatively limited to shear connections. Its assumption of pinned connection is less justifiable for some deep sections of beams, which may induce hogging moments, causing tension at the top reinforcement of the supports. In some cases of cantilever slabs, moment connections are necessary to maintain equilibrium. Hence, this paper reviews an up-to-date design methodology and installation guide to complement the Hong Kong Code of Practice for Structural Use of Concrete (HKBD) by referring to the recently published international design codes and documents. The proposal is useful to promote economical, sustainable and technically sound use of PIR system
Engineering and optimization of phosphate-responsive phytase expression in Pichia pastoris yeast for phytate hydrolysis
No full textPhytate is the major storage form of phosphorus in plants. It is present in cereals and raw materials of vegetable origin used in animal and human diets. However, non-ruminant animals have little phytase activity in their guts and, therefore, cannot digest phytate. As a result, almost all dietary phytate is discharged into the environment, causing phosphorus pollution. Phytate is also considered as an “antinutrient” for its ability to form insoluble and stable complexes with metal ions, thus reducing dietary absorption of essential minerals. It is a dire need to develop sustainable approaches for environmentally-friendly utilization for this valuable and abundant natural resource. To this end, we engineered Pichia pastoris to express and secrete phytase in a “made-to-order” fashion in response to external level of inorganic phosphate (Pi). Responsiveness to external Pi level was achieved by generating a Pi-responsive promoter library using directed evolution. The resultant yeast strains were proven to liberate Pi from wheat-based meal in a simulated in vitro digestion model. These yeast-based whole cell biocatalysts may serve as platform hosts with potential applications in food processing industry and animal waste treatment
Solvothermal synthesis of copper-doped BiOBr microflowers with enhanced adsorption and visible-light driven photocatalytic degradation of norfloxacin
No full text© 2020 Elsevier B.V. Photocatalysts based on copper-doped bismuth oxybromide (Cu-doped BiOBr) were synthesised using a solvothermal method and assessed for their ability to degrade norfloxacin under visible light. The Cu atoms were successfully doped into the crystal lattice of BiOBr, yielding Cu-doped BiOBr microflowers with a morphology and crystal structure identical to that of pristine BiOBr. The as-prepared Cu-doped BiOBr showed activity superior to BiOBr in the photocatalytic degradation of norfloxacin under visible-light irradiation, which was attributed to its improved light-harvesting properties, enhanced charge separation and interfacial charge transfer. Furthermore, we found for the first time that the introduction of Cu into BiOBr enhanced the adsorption capacity between the photocatalyst and norfloxacin, which we considered to be the main contribution to its improved performance. Cu-doped BiOBr containing the optimal proportion of Cu and Bi (Cu:Bi = 0.03) had a photocatalytic degradation constant of 0.64 ×10−2 min−1, which is 2.28 times higher than that of undoped BiOBr. The primary oxidation pathway was determined to involve the transfer of photogenerated holes to norfloxacin. Finally, we demonstrated that the Cu-doped BiOBr photocatalyst retained 95% of its initial activity even after five successive catalytic cycles, confirming its recyclability
Perceived importance and levels of technical English communication skills among stakeholders in engineering fields
Get PDFThe purposes of this study were to examine stakeholders’ perceptions of the importance of technical English communication skills in engineering and academic teachers and industry professionals’ perceptions of current engineering students’ and graduates’ levels of technical communication skills. Survey questionnaires were designed to collect data from different research participants. The data were subsequently analysed using descriptive statistics. The study identified a discrepancy between students’ self-perceived performance on technical English communication skills and their perceived standards of these skills required by the programmes in which they were enrolled. Technical communication skills, including writing in engineering genres, essays and technical reports, reading and speaking, were viewed to be fairly important for their academic success. The findings also indicated that the students’ abilities in writing in engineering genres, and essays and technical report writing were perceived to be below the standards. In addition, the study highlighted that industry professionals viewed the technical communication skills of engineering graduates working in the engineering sectors as inadequate. Based on these results, it is vitally important to develop a tailor-made enhancement course to cater for the specific needs of engineering students, including technical communication skills for their study programmes and to prepare them for workplace needs of engineers in the near future
The Impact of Competition-Based Learning on Enhancing Students’ Motivation, Engagement and Professionalism: A Case Study of Fashion Design Undergraduates in Hong Kong
No full text© 2020, Springer Nature Singapore Pte Ltd. In today’s competitive environment, an organization’s ability to design innovative solutions and products has become a critical driver for product differentiation and thereby organizational competitiveness. Design is a process of solving real-life problems often in collaboration with professionals in relevant fields. Design is conceived as a process of solving an ill-structured problem, which possesses multiple solutions, multiple solution paths, fewer parameters and uncertainty about what it takes to reach a solution
The Role of the Learning Organization to Effect Successful Change: VTC—A Case Study
No full text© 2020, Springer Nature Singapore Pte Ltd. Higher education has expanded rapidly since the last century following a global trend that has strengthened in recent decades (Lo & Tang, 2017). The main cause of this expansion being attributed to national competitiveness and the essential role which higher education plays especially in the context of the emerging knowledge economy. Globalization’s effect on higher education has been significant and substantive (Lo & Tang, 2017). One of these effects is the increase in access to higher education to a much greater proportion of the population (Eftimie, 2017)
Tool of the Trade 創意廚具
Get PDFFeel the heat
熱力四射
For high-temperature stir-frying, the wok is your go-to pan
中式炒鑊是烹調高溫煸炒菜式的最佳選
Lexicon 專業詞彙
Get PDFMother\u27s sauces
基本母醬
As students in ICI\u27s new Higher Diploma in Classic Western Cuisine programme are discovering, these sauces are the building blocks of French cuisine
國際廚藝學院新推出的經典西式廚藝高級文憑課程的學員領悟到，這些母醬皆是法國菜的基