Lignin engineering in forest trees

Wood is a renewable resource that is mainly composed of lignin and cell wall polysaccharides. The polysaccharide fraction is valuable as it can be converted into pulp and paper, or into fermentable sugars. On the other hand, the lignin fraction is increasingly being considered a valuable source of aromatic building blocks for the chemical industry. The presence of lignin in wood is one of the major recalcitrance factors in woody biomass processing, necessitating the need for harsh chemical treatments to degrade and extract it prior to the valorization of the cell wall polysaccharides, cellulose and hemicellulose. Over the past years, large research efforts have been devoted to engineering lignin amount and composition to reduce biomass recalcitrance toward chemical processing. We review the efforts made in forest trees, and compare results from greenhouse and field trials. Furthermore, we address the value and potential of CRISPR-based gene editing in lignin engineering and its integration in tree breeding programs

Mechanical Engineering: Medium-Sized Companies with Highest Savings Potential

The German mechanical engineering industry, dominated by medium-sized companies, is greatly successful - both on the domestic and on the international market. A first analysis conducted by DIW Berlin reveals that this success cannot be attributed to a better exploitation of potential efficiencies - mechanical engineering is about as efficient as other key sectors (for instance the chemical industry). In fact, despite their obvious success medium-sized mechanical engineering businesses have larger savings potential than bigger companies and even than smaller enterprises in this industry.Data envelopment analysis, German engineering firms, Efficiency, Firm size

Chemical research projects office: An overview and bibliography, 1975-1980

The activities of the Chemical Research Projects Office at Ames Research Center, Moffett Field, California are reported. The office conducts basic and applied research in the fields of polymer chemistry, computational chemistry, polymer physics, and physical and organic chemistry. It works to identify the chemical research and technology required for solutions to problems of national urgency, synchronous with the aeronautic and space effort. It conducts interdisciplinary research on chemical problems, mainly in areas of macromolecular science and fire research. The office also acts as liaison with the engineering community and assures that relevant technology is made available to other NASA centers, agencies, and industry. Recent accomplishments are listed in this report. Activities of the three research groups, Polymer Research, Aircraft Operating and Safety, and Engineering Testing, are summarized. A complete bibliography which lists all Chemical Research Projects Office publications, contracts, grants, patents, and presentations from 1975 to 1980 is included

Challenges to Developing Professional Skills in Undergraduate Chemical Engineers at a Minority Serving University

Undergraduate engineering students at a minority serving institution present unique challenges for professional skill development. Students in the Chemical Process Design II and III course sequence in chemical engineering at Texas A&M University-Kingsville are introduced repeatedly to the importance of communication skills, and the topics of professional engineering licensure and life-long learning. A fraction of these students have English as their second language, and development of oral and written communication skills to the level of fluency expected of engineers in the United States is challenging. The students are tested in their oral communication skills through delivery of six group-format project presentations in the two course sequence. The course sequence also requires significant written communication exercises, particularly in the second course which is a writing intensive course. The overall performance of those students with English as a second language is reasonably strong once the instructor’s grading expectations are realized and the students avail themselves of outside assistance, such as provided by the University Writing Center. The undergraduate student’s development of a sense of the importance of life-long learning is also challenging for the instructor to instill. An open-ended technical problem requiring solution as part of a senior design project is an opportunity for the instructor to use coaching methods to guide students to their own independent solution, thus reinforcing self-learning outside of the instructor-led paradigm. Instilling an interest for professional registration is also difficult to accomplish, in particular because the fraction of chemical engineers that become registered in their career is far less than in other engineering disciplines such as civil engineering. The approaches used to accomplish instruction of these important professional skills at a minority-serving institution are presented.Cockrell School of Engineerin

The Use of Poly(vinyl alcohol)-based Hydrogels in Biomedical Applications

Polymers have found increasing favor in biomedical applications due to the greater control that researchers can exert over their properties. Researchers have focused on the development of therapies using biologically compatible polymers due to their ability to limit potentially harmful interactions with the body. This research has led to advances in tissue engineering, controlled and targeted drug delivery, and other biomedical fields, with the goal of improving both the effectiveness and accessibility of health care. Poly(vinyl alcohol) (PVA) hydrogels possess several chemical properties that make them well suited for biomedical applications. These include inertness and stability, biocompatibility, and pH-responsiveness. As a result, PVA based materials have been studied for potential applications in areas of biomedicine such as targeted drug delivery, tissue engineering, and wound healing. This thesis examines the properties of PVA and seeks to understand how the chemical and physical structure affects their properties. It then examines how these properties enhance their utility in potential biomedical applications. Finally, it reviews the research into development of PVA based materials for three different biomedical applications.Chemical Engineerin

Desarrollo y evaluación de competencias transversales (comunicación oral) y validación de las rúbricas de la asignatura de grado Experimentación en Ingenieria Química II

Oral communication generic skill was development and assessed in 'Chemical Engineering Experimentation' subject of the Chemical Engineering Undergraduate Degree of University of Barcelona by means of rubrics. Meanwhile, students did the validation of other rubrics employed in the subject for several learning/assessment activities with the aim of appraising the methodological usefulness of rubrics to formative/summative assessment

Carbon nanotubes for epoxy Nanocomposites: a review on recent developments

Carbon nanotubes (CNTs) are one of the strongest and stiffest engineering fibres. Due to their unique combination of chemical and physical properties at an incredibly small size, they possess great potential to be used as nanofillers for many structural and functional materials, particularly in aerospace sector. Depending on the type, geometrical parameters, concentration, dispersion and many other factors, CNTs can significantly modify the mechanical, electrical and thermal properties of epoxy based materials. This review paper, covering methods of synthesis, composite processing techniques and properties, presents an overview of develop-ments in the field of CNT/ epoxy nanocomposites in recent years

Biomimetic apatite sintered at very low temperature by spark plasma sintering: Physico-chemistry and microstructure aspects

Nanocrystalline apatites analogous to bone mineral are very promising materials for the preparation of highly bioactive ceramics due to their unique intrinsic physico-chemical characteristics. Their surface reactivity is indeed linked to the presence of a metastable hydrated layer on the surface of the nanocrystals. Yet the sintering of such apatites by conventional techniques, at high temperature, strongly alters their physico-chemical characteristics and biological properties, which points out the need for "softer" sintering processes limiting such alterations. In the present work a non-conventional technique, spark plasma sintering, was used to consolidate such nanocrystalline apatites at non-conventional, very low temperatures (T° < 300 °C) so as to preserve the surface hydrated layer present on the nanocrystals. The bioceramics obtained were then thoroughly characterized by way of complementary techniques. In particular, microstructural, nanostructural and other major physico-chemical features were investigated and commented on. This work adds to the current international concern aiming at improving the capacities of present bioceramics, in view of elaborating a new generation of resorbable and highly bioactive ceramics for bone tissue engineering