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Glycerol hydrogenolysis to n‐propanol over Zr‐Al composite oxide‐supported Pt catalysts
Get PDFZr‐Al mixed oxide supported Pt catalysts with different Zr/Al mole ratios (2.5%Pt/ZrxAl1–xOy) were synthesized by an impregnation method and used for the selective hydrogenolysis of glycerol to n‐propanol in an autoclave reactor. The catalysts were fully characterized by X‐ray powder diffraction, Brunauer‐Emmett‐Teller surface area analysis, CO chemisorption, H2 temperature‐ programmed reduction, pyridine‐infrared spectroscopy, and NH3‐temperature‐programmed desorption. The results revealed that the Zr/Al ratio on the support significantly affected the size of the platinum particles and the properties of the acid sites on the catalysts. The catalytic performance was well correlated with the acidic properties of the catalyst; specifically, more acid sites contributed to the conversion and strong acid sites with a specific intensity contributed to the deep dehydration of glycerol to form n‐propanol. Among the tested catalysts, 2.5 wt% Pt/Zr0.7Al0.3Oy exhibited excellent selectivity for n‐propanol with 81.2% glycerol conversion at 240 °C and 6.0 MPa H2 pressure when 10% aqueous glycerol solution was used as the substrate. In addition, the effect of various reaction parameters, such as H2 content, reaction temperature, reaction time, and number of experimental cycles were studied to determine the optimized reaction conditions and to evaluate the stability of the catalyst. © 2018, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserve
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Get PDFDuring September, the exhibition Swiss Accessory and Watch Design by HEAD - Genève came to HKDI with a vision of the future for watch and jewellery desig
Charge-driven self-assembly synthesis of straw-sheaf-like Co3O4 with superior cyclability and rate capability for lithium-ion batteries
No full textRational structure design of anode materials plays crucial roles in the continuous improvement of electrochemical lithium storage performance for high performance lithium-ion batteries (LIBs). In this study, a novel hierarchical straw-sheaf-like Co3O4 (Co3O4-SSL) composed of numerous strongly tied nanoneedles was successfully synthesized with hydrothermal route by a charge-driven self-assembly strategy. Material characterizations indicated that typical length of nanoneedles was about 10 µm and the average diameter was about 80 nm. Mechanism studies implied that positively charged diallyldimethylammonium chloride (DDA) molecules played a key role in the formation of straw-sheaf-like structures. Impressively, when Co3O4-SSL was investigated as anode materials for electrochemical lithium storage, high specific capacity (e.g. 842.9 mAh g−1 after 300 cycles tested at 500 mA g−1), superior cycling stability (e.g. capacity retention of about 100% over 300 cycles) and excellent rate capability (e.g. 707 mAh g−1 tested at 3000 mA g−1) were achieved in the repeated charging-discharging cycles, demonstrating great potentials in energy storage materials. The proposed synthetic strategy is appealing in electrode structure design for next generation LIBs
Inter-disciplinary Research+Business Collaboration as a New Design Practice
No full textA ‘multidisciplinary nature’ of a design “research + business” practice can be a model for a metropolitan like Hong Kong with leading talents in the fields of design and business, utilizing existing technology such as Parametric Design, Building Information Modeling (BIM) and System Design. The high degree of automation, accuracy and efficient productivity can assist design fabrication and expedite processes of generating and managing data, encouraging more research and business collaborations to be formulated in a global network. The multidisciplinary collaborations can motivate cultural exchange by establishing more connectivity between designers and academia in all disciplines to generate specific improvements to health care and the built environment which share great synergies with the design disciplines. As a result, new categories of practices can emerge and more community stakeholders can take part in the design process. This proposed “research + business” design practice in its turn can rouse more interest and debates around broader notions of how the work of design industries go beyond traditional practice structures, challenging the nature of the designers and the profession’s education, canon, dialect and potentials. This new theory also diversifies ways of thinking about business and research, expanding institutional capacity to co-ordinate. It is pertinent for this concept to answer how design can emerge with a new design dialectic. How do designers structure the most effective model of practice in order to make new discovery? How can designers reclaim the role of innovators for our tomorrow? Such quests remain central to the future of the design profession, which urgently need the address from the comparative agencies of design and educational institutions in order to think outside of traditional mode and adapt a more speculative or unusual modes of designing our communities by embracing an interdisciplinary “research + business” practice
Using Facebook to Promote Student Engagement in Authentic Learning for Vocational Education and Training (VET)
Get PDFThe popularity of online social media has had a significant impact in education and has brought an amazing potential in promoting authentic learning. Authentic learning engages learners by the opportunities of actually participating and working on real-world problems that links the classroom theories. However, it can be a difficult shift without an adequate involvement of students. FaceBook due to its popularity and usefulness, teachers can not only introduce motivational authentic learning tasks but also allow students to come together to discuss, collaborate and resolve real-life problems. In this study, teachers gain the advantages of using Facebook as a tool to provide students experimental learning opportunities and students are encouraged to spend efforts to explore, discuss, exchange ideas in groups and meaningfully connect what they are taught in school to real-life problems and applications. These students are from the Hong Kong Institute of Vocational Education (Tsing Yi) and all of them are studying Higher Diploma in Civil Engineering. Purposive samplings are employed to find out the students’ preferences in using Facebook to introduce authentic learning opportunities among many other means. In the student survey, levels of engagement and possible learning activities such as sharing resources and interacting with other students are presented. This paper investigates the effectiveness of Facebook use in bringing up authentic learning opportunities and how the overall quality of students’ educational experience with this technology usage. The result has shown that the use of Facebook as a tool of promotion has a positive impact on student levels of engagement and has enhanced students’ learning experience such as sharing ideas with classmates
Lexicon 專業詞彙
Get PDFIn the raw
新鮮滋味
Many cuisines from around the world serve meats and fish in their raw state. The simple preparation allows the purity and quality of the ingredients to shine, with local condiments adding distinction
世界各地都有自己的生魚或生肉菜式。這些菜式重點在突顯食材本身的鮮味和品質，一般僅以本地調味品增添地方風