The knowledge misalignment between engineering and secondary school technology education

The majority of secondary school engineering education is delivered within Design and Technology. There is a misalignment between the background subject knowledge of these teachers and the subject knowledge of engineering. This paper presents key findings from the London Schools Excellence Fund Reference: LSEFR1210 study where teachers have difficulties in utilising science and math-based resources. This has implications for pupils’ receiving a desirable engineering education in school, which may be a factor in the number of pupils choosing to study engineering and technology beyond compulsory education

Pioneer Venus

Venus before Pioneer, the Pioneer Venus mission, Pioneer Venus spacecraft, scientific investigation, mission to Venus scientific results, and results of Soviet studies of Venus are addressed. A chronology of exploration of Venus from Earth before the Pioneer Venus mission and Venus nomenclature and mythology are provided

Phosphate removal from aqueous solutions by adsorption onto ammonium-functionalized mesoporous silica

Les activités agricoles génèrent des effluents riches entre autres en composés phosphorés dont le contrôle constitue un enjeu important du fait de leur implication directe dans le phénomène d'eutrophisation des milieux aquatiques. L'élimina'tion des composés phosphorés se trouvant dans les effluents d'origine agricole et agroalimentaire est conventionnellement effectuée au moyen de traitements biologiques ou de traitements physicochimiques. Les premiers sont souvent complexes, longs à opérer et délicats car ils dépendent de plusieurs facteurs tels que la température, le pH, la concentration en oxygène dissous et la balance des nutriments dans l'eau en plus de générer des boues volumineuses dont il faut disposer. Les traitements physicochimiques les plus employés impliquent la précipitation des espèces phosphorés qui nécessite un contrôle rigoureux du pH et l'ajout de réactifs chimiques souvent coûteux. De plus, ces traitements produisent un précipité insoluble de phosphore métallique qui est non recyclable. Le procédé d'adsorption peut constituer une alternative intéressante et prometteuse du fait qu'il ne produit pratiquement pas de boues en plus de permettre la récupération et la réutilisation des phosphates. Divers adsorbants ont été développés et utilisés pour l'enlèvement des ions phosphate mais leur capacité d'adsorption reste toujours faible et le temps pour atteindre l'équilibre est élevé ce qui nécessite impérativement le développement de nouveaux matériaux adsorbants. Dans cette étude, la silice mésoporeuse SBA -15 possédant une grande surface spécifique, une structure bien définie et une porosité élevée a été utilisée comme adsorbant pour les ions phosphate dissous. En effet, une fois synthétisée, cette silice a été fonctionnalisée en surface avec des groupements amines via la technique de greffage postsynthétique. L'acidification du matériau obtenu a permis de transformer les groupements amines en ammonium responsables du processus d'adsorption par attraction électrostatique. Les tests d'adsorption ont été effectués en batch et les solutions filtrées ont été analysées par HPLC ionique équipé d'une colonne Ionpac AS18 et d'un détecteur de conductivité. L'effet des paramètres opératoires tels que la température, le pH, le temps, la charge en adsorbant, la concentration initiale en ions phosphate, la charge en groupements amine ainsi que le type d'amine de la SBA -15 fonctionnalisée, la présence d'autre anions et cations ainsi que la régénération de l'adsorbent ont été investigués. Les résultats montrent qu'une capacité maximale de 27 mg P/g a été obtenue à SoC. L'adsorption atteint un maximum à pH 4 avec 2 une capacité d'adsorption de 31.5 P mg! g. L'équilibre d'adsorption a été atteint au bout de 10 min. L'augmentation de la charge en adsorbant avait un effet positif sur les pourcentages d'adsorption. La quantité adsorbée de P augmente avec l'augmentation de la concentration de mono- di- ét tri-ammonium jusqu à 40% avec un maximum de --70 mg P/g d'adsorbant. La capacité d'adsorption n'a pas changé après cinq cycles d'adsorption-désorption

Synthesis and characterization of organotriethoxysilanes based on carbohydrates for functional mesoporous organosilica hybrids

Cancer is the second leading cause of death worldwide. Conventional therapies are characterized by clinical inefficiency and serious side effects, like high toxicity in healthy tissues. For these reasons, the investigation for more effective therapies increased in the recent years. With the progress in the area of medicinal chemistry, we read headlines almost every day about potential promising new drugs on the horizon for diseases like cancer, however, these drugs present poor stability, high toxicity, small half-lives, aggregation tendency and the transport is hindered by biobarriers such as the blood brain barrier or cell membranes. To solve these problems, researchers from different areas, such as biology, materials science, pharmacy, medicinal chemistry and chemistry, have oriented their work with the aim to develop more efficient drug delivery systems. In the past decades, the advances of nanotechnology have facilitated the development of several nanovehicles as drug delivery systems, as an advantage in the field of Medicinal Chemistry. Among the nanomaterials proposed, hybrid mesoporous organosilicas have aroused significant interest as candidates for nanomedical applications. The aim of this work was to synthesize mono-organosilanes precursors based on carbohydrates derivatives. The use of carbohydrate as organic part is an innovative work with great potential to prepare anti-tumoral supports for drug delivery, once carbohydrates are involved in numerous important biological processes linked to cancer. In the first part of the present work, was synthesised the carbohydrates derivates, from D-glucose, D-ribose, 1,2:5,6-di-O-isopropylidene-a-D-glucofuranose and methyl-?-D-glucopyranoside. In the second part of the work, was prepared the organotriethoxysilanes involving a cross-link between the carbohydrate derivatives and 3-(triethoxysilyl)propyl isocyanate. Then, these organotriethoxysilanes will be used to functionalized mesoporous hybrids organosilica, with the aim of achieve carrier systems for anti-tumoral drug delivery. The functionalities into the mesoporous materials will interact with potential new drugs or others already in the market, and release them to the specific target sites, giving new and better ways to hit the disease target.Atualmente, o cancro é segunda maior causa de morte no mundo, e a as terapias ditas convencionais, como por exemplo, a quimioterapia, trazem diversos efeitos adversos para o paciente, nomeadamente a elevada toxicidade nos tecidos saudáveis. Este tipo de terapias é ineficaz porque os métodos utilizados não são seletivos para o alvo pretendido. Posto isto, e devido à taxa limitada de sucesso e às consequências não desejadas das terapias convencionais, a procura de novas alternativas, é primordial, nomeadamente a procura de terapêuticas eficazes e seletivas, que promovam uma libertação controlada e uma entrega precisa no sítio-alvo biológico. Estes são os principais objetivos na área da química medicinal. Os avanços na nanotecnologia têm facilitado o desenvolvimento de vários nano-veículos como sistemas de entrega de fármacos, o que se tornou numa vantagem na área da química medicinal. Os materiais híbridos mesoporosos de sílica têm atraído muita atenção devido as suas propriedades únicas, incluindo uma elevada área de superfície especifica, um grande volume de poro, tamanho do poro ajustável, natureza não tóxica, pouca reatividade para quelar grupos presentes no sistema, estabilidade química e a possibilidade de modificação da superfície do poro. A funcionalização destes materiais com precursores organotrietoxisilanos, permite a obtenção de materiais híbridos multifuncionais com características sem precedentes e combinações únicas, que permitiram a interação com fármacos e a sua libertação em locais específicos a uma velocidade controlada. A utilização de hidratos de carbono como componente orgânica na síntese deste tipo de precursores é um trabalho inovador e pode ser uma vantagem na medida em que, são considerados os produtos naturais funcionalmente mais versáteis e podem originar glicoconjugados com grande importância em diversas áreas, particularmente na indústria farmacêutica, uma vez que vez que estão envolvidos em inúmeros processos biológicos, nomeadamente no reconhecimento da superfície celular. Consequentemente, a química medicinal dos hidratos de carbono tem sido incrivelmente desenvolvida ao longo dos anos assim como o seu uso como agentes terapêuticos. Além disso, a facilidade com que este tipo de moléculas tem em estabelecer ligações com outros compostos, faz deles ótimos candidatos para funcionalização de sistemas de entrega de fármacos, aumentando a sua eficácia, atividade e diminuindo possíveis efeitos adversos. Deste modo, por forma a obter precursores organotrietoxisilanos baseados em derivados de hidratos de carbono, foram elaboradas uma série de reações: (1) proteção e desproteção seletiva de açúcares, por forma a melhorar a sua solubilidade no tipo de solventes utilizados nas reações consequentes; (2) reações de formação de precursores organotrietoxisilanos do tipo Z3Si-R, entre os derivados glucídicos e o 3-(trietoxisilil)propil isocianato. A síntese dos derivados de hidratos de carbono foi efetuada com base em três sequências reacionais. A primeira sequência reacional iniciou-se na metil-a-D-glucopiranose e na D-glucose e em cada um destes compostos foram realizadas reações de titilação, seguidas de uma acetilação e por ultimo uma destritilação, originando os compostos 2,3,4–O-triacetil–1–O–metil–ß–D-glucopiranose e 1,2,3,4-tetracetil-ß-D-glucopiranose respetivamente. A segunda sequência reacional iniciou-se com a D-ribose, a qual foi protegida com um grupo metil no hidroxilo do carbono 1 e protegida com o grupo isopropopilideno nas posições dos carbonos 2 e 3, num só passo, originando o metil-2,3-O-isopropilideno-ß-D-ribofuranose. A terceira e ultima sequência reacional iniciou-se com o 1,2:5,6-di-O-isopropilideno-a-glucofuranose que foi benzilado, e de seguida foi feita uma hidrólise, com o objetivo de remover os isopropilidenos das posições referentes aos carbonos 5 e 6. Posteriormente, foi feita uma clivagem oxidativa para a formação do aldeído na posição referente ao carbono 5. Numa fase seguinte, tentou sintetizar-se uma hidrazona através da redução do aldeído anteriormente sintetizado. Contudo, não foi possível obter-se o produto proposto, devido ao excesso de aldeído comparativamente à quantidade de hidrato de hidrazina utilizada na sua reação de síntese, ocorrendo uma dimerização, e formando-se a azina 5-(1’,2’-dimetilenehidrazona)–bis-[3-O-Benzil-1,2:5,6-di-O-isopropylidene-a-D-glucopiranose]. 1,2:5,6-di-O-isopropilideno-a-glucofuranose e 1,2-O-Isopropilideno-a-D-xilofuranose também foram utilizados como componente orgânica para a síntese de precursores. Numa fase seguinte, foi realizada a síntese dos precursores organotrietoxisilanos, sendo a ligação entre o componente derivado de hidrato de carbono e o 3-(trietoxisilil)propil isocianato, efetuada por nós de reticulação de tipo ureia e uretano Devido à impossibilidade de formação da hidrazona, optou-se por sintetizar o precursor 3,5,6-tri-O-metil(3-(trietoxisilil)propil)carbamato-1,2:5,6-di-O-isopropilideno-a–D-glucofuranose. Os compostos propostos foram todos sintetizados com sucesso, com exceção dos compostos Bis(3,5-O-metil(3-(trietoxisilil)propil-carbamato-1,2-O-isopropilideno-a–D-glucofuranose) e 3,5,6-tri-O-metil(3-(trietoxisilil)-propil)carbamato-1,2:5,6-di-O-isopropilideno-a–D-glucofuranose, que por falta de tempo não foi possível uma nova tentativa de síntese, através de uma metodologia diferente. Os precursores organotrietoxisilanos foram obtidos com rendimentos entre 65% e 90%. As sínteses dos precursores organotrietoxisilanos baseados em hidratos de carbono, revelaram um tempo de reação bastante longo e um constante aperfeiçoamento, tanto da temperatura, como do tempo de reação, assim como do solvente a ser utilizado é necessário. O controlo dos parâmetros de reação é essencial, uma vez que neste tipo de compostos pode facilmente haver hidrólise dos grupos etóxidos e consequente perda do precursor. Nesta dissertação são apresentados os resultados da síntese e a caracterização estrutural dos derivados de hidratos de carbono e dos respetivos precursores organotrietoxisilanos, sendo as respetivas estruturas dos compostos obtidos, comprovadas por espetroscopia de 1H-RMN, de 13C-RMN e ainda por espetroscopia de infravermelho

The effect of teacher’s confidence on technology and engineering curriculum provision

Secondary school, age range 11 – 14, technology and engineering education in England has been delivered mainly within Design and Technology (D&T). This inadvertently makes D&T teachers responsible for pupils’ engineering education and motivation. This paper analyses D&T teachers’ (N = 33) technology subject knowledge through self-assessment competency questionnaires, before and after developing a Science, Technology, Engineering and Mathematics (STEM)-focused project of their choice for their classroom. Participants were least confident in teaching the areas of technology that required mathematics and scientific knowledge. The results analyse a suggested misalignment between teachers’ Creative Arts background subject knowledge compared to the technology subject knowledge required for engineering education. Suggested causes of this issue are Initial Teacher Training (ITT) standards and curriculum flexibility, not teacher capability. The paper concludes that teachers have been unaware of some elements of STEM education and that continuing professional development interventions are required to assist teachers and improve their engineering knowledge in order to better equip their pupils for engineering

Study guide on “Technology of Structural materials and Material Science” Part 3

Study guide on have been approved at the meeting of building mechanics department (minutes No 1 from 25 August 2016) The Study guide on have been approved by the Mechanical Engineering Faculty methodological committee (minutes No 1 from 29 August 2016)“Technology of Structural materials and Material Science” is one of the basic technical disciplines in the syllabus for “Engineering mechanics” field of study. During the implementation of laboratory work considerable attention is given to the educational and experimental work for the study of materials that are used in different branches of an industry; methods of treatment and external environments The study of the theory and practice of different methods of materials strengthening is to provide a high reliability and longevity of the machine’s details, devices, tools etc. After every practical class and lab activities in the laboratory, students will fill the laboratory report. The content of the laboratory class corresponds with the syllabus of the course “Technology of Structural materials and Material Science” for students of the “Engineering mechanics” field of study. The purpose of this manual is to provide guidelines for the students in preparation for independent laboratory work and to project its results in the laboratory reports

POROUS NANOMATERIALS AS CONTROLLED DRUG DELIVERY SYSTEMS

MIL-53(Fe) was synthesized by conventional electric (CE) heating, and by ultrasound (UTS) and microwave (MW) irradiation to develop rapid and energy efficient synthesis techniques. MW and UTS conditions rapidly produced small and highly crystalline materials in 10 and 7 minutes, respectively. The energy consumption of UTS and MW irradiation were less than CE heating, confirming that these two technologies are quicker, more efficient and greener alternatives to conventional synthesis methods. The use of MIL-53(Fe), MIL-101, and SBA-15 as matrices for the adsorption and in vitro drug delivery of acetaminophen, progesterone, and stavudine was studied. An initial burst release from both MIL-53(Fe) and MIL-101 was followed by a slow diffusion-controlled release, which occurred for up to 6 and 5 days, respectively. Complete release from SBA-15 occured in as quickly as 30 minutes as a result of rapid drug dissolution and diffusion out of the pores

An investigation into the knowledge and skill requirements for effective teaching of technology in english secondary schools

This thesis is concerned with the knowledge and skill requirements to teach technology education. Technology education has an important part to play in the UK economy. There is great demand to produce a technologically skilled workforce and secondary school technology education is a key element in the supply of skilled engineering technicians and graduates. Whilst there have been improvements in the number of pupils choosing to study mathematics and science there has been a decline in those studying technology. The work in this thesis has focused on the subject of Design and Technology as it provides pupils with the majority of their compulsory technology education in England. This thesis is comprised of four studies, adopting a mixed-methods approach. The first study characterised the background knowledge of Design and Technology teachers through a demographic analysis. In the second study observations were made on the adoption and teaching of a novel technology resource by trainee teachers. The third study analysed the opinions of teachers who attended a subject knowledge enhancement professional development course. In the fourth study the results of the previous studies were explored in further detail to triangulate findings and to test assumptions. In the first study the admissions data of 341 trainee Design and Technology teachers over the academic years 2000-2001 and 2013-2014 inclusive was analysed. The key finding of this analysis was that 81% of Design and Technology teachers have their entry qualification in creative arts and design and not in a technology subject. This misalignment of subject knowledge was discussed to be a result of the existing training standards and hypothesised to be contributory to the lack of technology teaching, and over emphasis of design in Design and Technology. The second study used observational methods to record how three trainee teachers adopted and taught lessons using a novel technology resource created for the study. The resource was designed to teach laser cutting and the design of mechanical systems. Subsequent analysis revealed the difficulties participants had in understanding and teaching the technology aspects of the projects. The existing practice, and collective knowledge of teachers within the schools used in the study were found to create obstacles for the trainees in trying to implement technological content. The third study developed a new professional development course for teachers to address the issues observed in the second study. The quantitative and qualitative data was obtained from 20 participant design and technology teachers before, during and after the course. Participants reported to be confidence in teaching technology, yet were unable to demonstrate a deep understanding of the subject content. Participants engaged with the procedural knowledge aspects of the course but not with the conceptual knowledge. They considered many aspects of technological and engineering content to be irrelevant to pupils. The fourth, and final, study developed questionnaires to assess teacher and pupil reactions to the provision of 57 different technology projects resources and training sessions to 82 schools across London. Useable data were generated from 33 teachers and 458 pupils. Measurements of teachers confidence in teaching the new Technology National Curriculum revealed that teachers strengths were the making of products. The weaknesses were teaching modern mechanical and electrical systems. Pupils motivation towards technology revealed positive attitudes, but they were unaffected by resources teachers considered to be novel. This study was used to triangulate the findings of the previous study and validate the claims made. The major contribution to knowledge of this thesis is the quantified description and analysis of teachers technology knowledge. The interrelationships of the distinct teacher knowledge domains were analysed to discover how they affect technology education. The main conclusion of this study is that teachers have difficulties in developing and teaching technology based schemes of work to meet the National Curriculum requirements. However, teachers appear unaware of this situation and consider themselves confident in teaching the technology curriculum topics. These difficulties have been caused by teachers lack of compatible background subject knowledge, and were evident in the teaching of projects without secure technology content. This thesis recommends that a significant intervention is required to provide support to Design and Technology teachers to develop their knowledge and skills in teaching technology

Developing nanotechnology for biofuel and plant science applications

This dissertation presents the research on the development of mesoporous silica based nanotechnology for applications in biofuels and plant science. Mesoporous silica nanoparticles (MSNs) have been the subject of great interest in the last two decades due to their unique properties of high surface area, tunable pore size and particle morphology. The robust nature of the silica framework is easily functionalized to make the MSNs a promising option for selective separations. Also, the independent channels that form the pores of MSN have been exploited in the use of particles as platforms for molecular delivery. Pore size and organic functionality are varied to identify the ideal adsorbent material for free fatty acids (FFAs). The resulting material is able to sequester FFAs with a high degree of selectivity from a simulated solution and microalgal oil. The recyclability and industrial implications are also explored. A continuation of the previous material, further tuning of MSN pore size was investigated. Particles with a smaller diameter selectively sequester polyunsaturated free fatty acids (PUFAs) over monounsaturated FFAs and saturated FFAs. The experimental results were verified with molecular modeling. Mesoporous silica nanoparticle materials with a pore diameter of 10 nm (MSN-10) were decorated with small gold nanoparticles. The resulting materials were shown to deliver proteins and DNA into plant cells using the biolistic method