The Experts below are selected from a list of 279 Experts worldwide ranked by ideXlab platform

Grace Q. Chen - One of the best experts on this subject based on the ideXlab platform.

  • Current progress towards the metabolic engineering of plant seed oil for hydroxy fatty acids production
    Plant Cell Reports, 2015
    Co-Authors: Grace Q. Chen
    Abstract:

    Key message Hydroxy fatty acids produced in plant seed oil are important Industrial Material. This review focuses on the use of metabolic engineering approaches for the production of hydroxy fatty acids in transgenic plants. Abstract Vegetable oil is not only edible but can also be used for Industrial purposes. The Industrial demand for vegetable oil will increase with the continued depletion of fossil fuels and ensuing environmental issues such as climate change, caused by increased carbon dioxide in the air. Some plants accumulate high levels of unusual fatty acids in their seeds, and these fatty acids (FAs) have properties that make them suitable for Industrial applications. Hydroxy fatty acids (HFAs) are some of the most important of these Industrial FAs. Castor oil is the conventional source of HFA. However, due to the presence of toxin ricin in its seeds, castor is not cultivated on a large scale. Lesquerella is another HFA accumulator and is currently being developed as a new crop for a safe source of HFAs. The mechanisms of HFA synthesis and accumulation have been extensively studied using castor genes and the model plant Arabidopsis . HFAs accumulated to 17 % in the seed oil of Arabidopsis expressing a FA hydroxylase gene from castor ( RcFAH12 ), but its seed oil content and plant growth decreased. When RcFAH12 gene was coexpressed with additional castor gene(s) in Arabidopsis , ~30 % HFAs were accumulated and the seed oil content and plant growth was almost restored to the wild-type level. Further advancement of our understanding of pathways, genes and regulatory mechanisms underlying synthesis and accumulation of HFAs is essential to developing and implementing effective genetic approaches for enhancing HFA production in oilseeds.

  • current progress towards the metabolic engineering of plant seed oil for hydroxy fatty acids production
    Plant Cell Reports, 2015
    Co-Authors: Grace Q. Chen
    Abstract:

    Key message Hydroxy fatty acids produced in plant seed oil are important Industrial Material. This review focuses on the use of metabolic engineering approaches for the production of hydroxy fatty acids in transgenic plants.

Martin C Schubert - One of the best experts on this subject based on the ideXlab platform.

  • solar cell efficiency losses due to impurities from the crucible in multicrystalline silicon
    IEEE Journal of Photovoltaics, 2014
    Co-Authors: Florian Schindler, B Michl, Jonas Schon, Wolfram Kwapil, Wilhelm Warta, Martin C Schubert
    Abstract:

    The electrical Material quality of multicrystalline (mc) silicon for photovoltaic applications suffers from crystal defects as well as from impurities that originate from the feedstock, the quartz crucible, and its coating. In this study, we investigate the influence of impurities from the crucible on efficiency losses in mc silicon solar cells, focusing on the limitation due to iron. The applicability of p-type mc silicon, crystallized in G1 sized crucibles of Industrial Material quality and very pure electrically fused silica, for a high-efficiency solar cell process is examined by measuring lifetime and interstitial iron concentration in the wafers after different processing steps and by estimating the cell efficiency potential from injection-dependent bulk lifetime measurements. Interstitial iron concentrations extracted from 2-D simulations of iron precipitation at crystal defects and gettering during processing agree well with Fei measurements at different process stages and explain the observations. Efficiency losses are quantified to losses due to segregated impurities diffused into the silicon melt, losses due to decorated crystal defects and losses due to solid-state diffusion into the crystal. By using a high-purity crucible, losses are reduced significantly and an efficiency gain of 0.5% absolute is estimated to be attainable on wafers with edge region.

Toshiaki Ougizawa - One of the best experts on this subject based on the ideXlab platform.

Massimo Tonelli - One of the best experts on this subject based on the ideXlab platform.

  • in situ esem study of the thermal decomposition of chrysotile asbestos in view of safe recycling of the transformation product
    Journal of Hazardous Materials, 2008
    Co-Authors: Alessandro F Gualtieri, Magdalena Lassinantti Gualtieri, Massimo Tonelli
    Abstract:

    Abstract The thermal transformation of asbestos into non-hazardous crystalline phases and their recycling is a promising solution for the “asbestos problem”. The most common asbestos-containing Industrial Material produced worldwide is cement-asbestos. Knowledge of the kinetics of thermal transformation of asbestos fibers in cement-asbestos is of paramount importance for the optimization of the firing process at Industrial scale. Here, environmental scanning electron microscopy (ESEM) was used for the first time to follow in situ the thermal transformation of chrysotile fibers present in cement-asbestos. It was found that the reaction kinetics of thermal transformation of chrysotile was highly slowed down in the presence of water vapor in the experimental chamber with respect to He. This was explained by chemisorbed water on the surface of the fibers which affected the dehydroxylation reaction and consequently the recrystallization into Mg-silicates. In the attempt to investigate alternative and faster firing routes for the decomposition of asbestos, a low melting glass was mixed with cement-asbestos and studied in situ to assess to which extent the decomposition of asbestos is favored. It was found that the addition of a low melting glass to cement-asbestos greatly improved the decomposition reaction and decreased the transformation temperatures.

Dierk Raabe - One of the best experts on this subject based on the ideXlab platform.