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Process Steps (process + step)
Selected AbstractsEnantioselective Symmetry Breaking Directed by the Order of Process Steps,ANGEWANDTE CHEMIE, Issue 14 2010Die Konfiguration des Produkts einer durch Verreiben ausgelösten Symmetriebrechung wird durch die Reihenfolge bestimmt, in der die Bestandteile kombiniert werden (siehe Schema: I),Glaskügelchen, II),racemische Mischung (die Enantiomere sind farblich unterschieden), III),Solvens, IV),Racemisierungskatalysator). Der zugrundeliegende Mechanismus beruht auf einer feinen Balance zwischen enantioselektivem Kristallwachstum und -auflösen. [source] Microfluidic tectonics platform: A colorimetric, disposable botulinum toxin enzyme-linked immunosorbent assay systemELECTROPHORESIS, Issue 10-11 2004Jaisree Moorthy Abstract A fabrication platform for realizing integrated microfluidic devices is discussed. The platform allows for creating specific microsystems for multistep assays in an ad hoc manner as the components that perform the assay steps can be created at any location inside the device via in situ fabrication. The platform was utilized to create a prototype microsystem for detecting botulinum neurotoxin directly from whole blood. Process steps such as sample preparation by filtration, mixing and incubation with reagents was carried out on the device. Various microfluidic components such as channel network, valves and porous filter were fabricated from prepolymer mixture consisting of monomer, cross-linker and a photoinitiator. For detection of the toxoid, biotinylated antibodies were immobilized on streptavidin-functionalized agarose gel beads. The gel beads were introduced into the device and were used as readouts. Enzymatic reaction between alkaline phosphatase (on secondary antibody) and substrate produced an insoluble, colored precipitate that coated the beads thus making the readout visible to the naked eye. Clinically relevant amounts of the toxin can be detected from whole blood using the portable enzyme-linked immunosorbent assay (ELISA) system. Multiple layers can be realized for effective space utilization and creating a three-dimensional (3-D) chaotic mixer. In addition, external materials such as membranes can be incorporated into the device as components. Individual components that were necessary to perform these steps were characterized, and their mutual compatibility is also discussed. [source] Synthesis and Characterization of Alumina Microtubes in a Template Process from Short Carbon Fibers,ADVANCED ENGINEERING MATERIALS, Issue 5 2007Z. Pajkic A novel, two step process for synthesis of Al2O3 microtubes from short carbon fibers as templates is reported. In the first process step, the carbon fibers are coated with a Al-AlN-Al4C3 composite in a microwave plasma fluidized bed CVD process. The coated material is then being treated in a furnace on high temperature in air, resulting finaly with alumina microtubes (hollow fibers). [source] High-Temperature Contact Formation on n-Type Silicon: Basic Reactions and Contact Model for Seed-Layer ContactsADVANCED FUNCTIONAL MATERIALS, Issue 3 2010Matthias Hörteis Abstract Contact formation on n-type silicon, especially using a high-temperature process, has been the subject of research for more than 40 years. After its application in microelectronics, n-type silicon is widely used in silicon solar cells as the emitter layer. The formation of a low ohmic contact grid using an industrially feasible process step is one of the key features required to improve the solar-cell efficiency. The contact materials, typically deposited in a printing step, have to fulfil several functions: opening the dielectric antireflection layer and forming an intimate metal-semiconductor contact with good mechanical adhesion and low specific contact resistance. As the used contact inks typically contain several functional materials, such as silver and a glass frit, the detailed contact formation is still not entirely understood. Therefore, the chemical reactions during the contact firing process have been studied in detail by thermogravimetric differential thermal analysis in combination with mass spectroscopy. Based on these studies, a contact ink has been developed, optimized and tested on silicon solar cells. In this paper, the mechanism of the etching process, the opening of a dielectric layer, the influence of different atmospheres and the impact of the glass-frit content are investigated. The observed microscopic contact structure, the resulting electrical solar-cell parameters and the studied reactions are combined to clarify the physics behind the high-temperature contact formation. [source] Pathogen safety of manufacturing processes for biological products: special emphasis on KOGENATE® BayerHAEMOPHILIA, Issue 2002D. C. Lee Summary., Manufacturers of human therapeutic proteins derived from biological sources continuously strive to improve the pathogen safety profiles of these products. Efforts to improve pathogen safety margins for these biological products are directed towards several areas within the manufacturing processes including: (a) sourcing and screening of raw materials (b) determining the potential for manufacturing processes to reduce pathogen titres, and (c) incorporating methods designed specifically to remove or inactivate contaminating pathogens. Methods that could potentially reduce pathogen titres are a major focus for many manufacturers. In general, these methods are grouped into two categories, pathogen clearance and pathogen inactivation. Assessments are performed on small-scale, laboratory simulations of the manufacturing process of interest that are spiked with a known amount of a selected pathogen. These studies provide estimates of the potential for a process step to remove or inactivate a particular pathogen. There are several pathogen clearance/inactivation methods that are inherent in manufacturing processes, however, some methods are intentionally incorporated into manufacturing for the sole purpose of reducing putative pathogen titres. Not only are well-known pathogens such as viruses targeted, but also suspected pathogens such as those associated with the transmissible spongiform encephalopathies (TSEs). The production processes for the isolation of several biological products, including recombinant KOGENATE® Bayer (Kogenate®FS), have been evaluated for the ability to reduce pathogen titres and/or have been designed to incorporate methods for reducing potential pathogen safety risks. Several processing steps with the potential to reduce pathogen titres have been identified. [source] Zero Shrinkage of LTCC by Self-Constrained SinteringINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 5 2005Torsten Rabe Low shrinkage in x and y direction and low tolerances of shrinkage are an indispensable precondition for high-density component configuration. Therefore, zero shrinkage sintering technologies as pressure-assisted sintering and sacrificial tapes have been introduced in the low-temperature co-fired ceramics (LTCC) production by different manufacturers. Disadvantages of these methods are high costs of sintering equipment and an additional process step to remove the sacrificial tapes. In this article, newly developed self-constrained sintering methods are presented. The new technology, HeraLock®, delivers LTCC modules with a sintering shrinkage in x and y direction of less than 0.2% and with a shrinkage tolerance of ±0.02% without sacrificial layers and external pressure. Each tape is self-constrained by integration of a layer showing no shrinkage in the sintering temperature range of the LTCC. Large area metallization, integration of channels, cavities and passive electronic components are possible without waviness and camber. Self-constrained laminates are an alternative way to produce zero shrinkage LTCC. They consist of tapes sintering at different temperature intervals. Precondition for a successful production of a self-constrained LTCC laminate is the development of well-adapted material and tapes, respectively. This task is very challenging, because sintering range, high-temperature reactivity and thermal expansion coefficient have to be matched and each tape has to fulfill specific functions in the final component, which requires the tailoring of many properties as permittivity, dielectric loss, mechanical strength, and roughness. A self-constrained laminate is introduced in this article. It consists of inner tapes sintering at especially low-temperature range between 650°C and 720°C and outer tapes with an as-fired surface suitable for thin-film processes. [source] Protein disaggregation and refolding using high hydrostatic pressureJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 7 2007David J Phelps Abstract Production of recombinant proteins often leads to aggregate formation. These aggregates may make it impossible to solubilize the protein for downstream applications such as assay development or structural studies by X-ray crystallography or nuclear magnetic resonance spectroscopy. High hydrostatic pressure technology has been developed which offers significant advantages over traditional methods of protein disaggregation and refolding. Pressure induced disruption of protein aggregates and subsequent refolding can take place at high concentrations in a single process step, without the need for high concentrations of chaotropic agents. Copyright © 2007 Society of Chemical Industry [source] Use of software to facilitate pharmaceutical formulation,experiences from a tablet formulationJOURNAL OF CHEMOMETRICS, Issue 3-4 2004Nils-Olof Lindberg Abstract This paper exemplifies the benefits of using experimental design together with software to facilitate the formulation of a tablet for specific purposes, from screening to robustness testing. By applying a multivariate design for the screening experiments, many excipients were evaluated in comparatively few experiments. The formulation work was generally based on designed experiments. Most of the experiments were fractional or full factorial designs, generated and evaluated in Modde with the centre point replicated. The robustness of the formulation was evaluated with experimental designs on two different occasions. Tested flavours were found to have limited influence on the important responses, which was key information in order to proceed with that particular composition. The formulation was also robust towards normal batch-to-batch variation of the excipients and the active pharmaceutical ingredient. A process step was investigated and, by applying experimental design and keeping in mind previous findings, important information could be gained from the study. The different studies yielded good and very useful models. Established relationships between design factors and responses provided information that was vital for the project. In cases of poor models, essential information regarding robustness was obtained. Copyright © 2004 John Wiley & Sons, Ltd. [source] Atomic force microscopic analysis of hydrogen peroxide bleached kraft northern black spruce fibresJOURNAL OF MICROSCOPY, Issue 2 2005M. A. POGGI Summary Hydrogen peroxide is a potent, relatively inexpensive oxidant that chemically degrades chromophoric components in pulps and textiles. Oxidation of cellulose is a byproduct of this process step that decreases the tensile strength of individual fibres. The residence time of pulp in the bleaching reactor must be optimized to achieve the desired brightness and minimizing fibre degradation. To evaluate the impact of peroxide bleaching at the microfibrillar level, a single black spruce tree was chosen and kraft pulped. Peroxide bleaching was conducted via benchtop polyethylene bag bleaching in a temperature-controlled waterbath. Atomic force microscopy (AFM) topographical images acquired before and after the bleaching step show dramatic changes in fibre structure consistent with delignification and defects in the surface topography. This was further verified by X-ray work at Brookhaven National Laboratory, NY, U.S.A. [source] Evaluation of a critical process parameter: Oxygen limitation during cultivation has a fully reversible effect on gene expression of Bordetella pertussisBIOTECHNOLOGY & BIOENGINEERING, Issue 1 2009Mathieu Streefland Abstract Modern (bio)pharmaceutical process development requires thorough investigation of all process parameters that are critical to product quality. The impact of a disturbance of such a parameter during processing needs to be known so that a rational decision can be made about the release of the product. In cultivation processes the dissolved oxygen (DO) concentration is generally accepted as being a critical parameter. In this article the impact of a 90 min period of oxygen limitation during the cultivation of the strictly aerobic Bordetella pertussis bacterium is investigated. The cultivation is the most important process step for the manufacturing of a vaccine against whooping cough disease. Samples were taken immediately before and after oxygen limitation and at the end of cultivation of four oxygen limited and three control cultivations. DNA microarray analysis of the full transcriptome of the B. pertussis bacterium revealed that a 90 min period of oxygen limitation has a substantial effect on overall gene expression patterns. In total 104 genes were identified as a significant hit at any of the sample points, of which 58 were directly related to oxygen limitation. The other genes were mainly affected towards the end of cultivation. Of all genes involved in oxygen limitation none were identified to show a significant difference between the oxygen limited and control cultivations at the end of the batch. This indicates a fully reversible effect of oxygen limitation on gene expression. This finding has implications for the risk assessment of dissolved oxygen concentration as a critical process parameter. Biotechnol. Bioeng. 2009;102: 161,167. © 2008 Wiley Periodicals, Inc. [source] Product and contaminant measurement in bioprocess development by SELDI-MSBIOTECHNOLOGY PROGRESS, Issue 3 2010Alex Berrill Abstract Bioprocesses for therapeutic protein production typically require significant resources to be invested in their development. Underlying these efforts are analytical methods, which must be fit for the purpose of monitoring product and contaminants in the process. It is highly desirable, especially in early-phase development when material and established analytical methods are limiting, to be able to determine what happens to the product and impurities at each process step with small sample volumes in a rapid and readily performed manner. This study evaluates the utility of surface-enhanced laser desorption ionization mass spectroscopy (SELDI-MS), known for its rapid analysis and minimal sample volumes, as an analytical process development tool. In-process samples from an E. coli process for apolipoprotein A-IM (ApoA-IM) manufacture were used along with traditional analytical methods such as HPLC to check the SELDI-MS results. ApoA-IM is a naturally occurring variant of ApoA-I that appears to confer protection against cardiovascular disease to those that carry the mutated gene. The results show that, unlike many other analytical methods, SELDI-MS can handle early process samples that contain complex mixtures of biological molecules with limited sample pretreatment and thereby provide meaningful process-relevant information. At present, this technique seems most suited to early-phase development particularly when methods for traditional analytical approaches are still being established. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] Confocal Raman Microscopy as a Tool to Investigate Concentration Profiles of Melt Crystallized Ibuprofen/Carnauba WaxCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 7 2009H. Qu Abstract Coatings are of great significance for pharmaceutical solid dosage forms. They fulfil a number of functions and are often necessary to control drug delivery, to mask bitter taste, or to protect the active pharmaceutical ingredient from detrimental environmental factors. The process of self-coating by melt crystallization of a suitable binary mixture eliminates the need for an additional process step in the manufacture of a solid drug. Self-coating relies upon the physical and spatial separation of individual components in a melt during solidification. This paper focuses on the use of confocal Raman microscopy as a nondestructive technique for quantifying the spatial distribution of the components in self-coated pastilles manufactured from the binary system ibuprofen/carnauba wax. Pastilles are produced from the melt. Raman spectroscopy allows the direct analysis of concentration profiles across the surface of the pastille. Here, the samples are cleaved and the cleaved surface is investigated in order to establish the distribution of the components in the interior of the solid. A univariate calibration model was developed and statistically validated with standard mixtures of ibuprofen and carnauba wax. Different regression models (linear or polynomial, using different significant peaks for the respective compounds) were assessed and a linear model was found to be adequate to determine the concentration gradient in the pastilles. [source] Influences of the Process Chain on the Fatigue Behavior of Samples with Tension Screw Geometry,ADVANCED ENGINEERING MATERIALS, Issue 4 2010Marcus Klein To analyze the influence of the material batch, the structure of the manufacturing process chain, and the process parameters, four different material batches of the quenched and tempered steel SAE 4140 were used to manufacture samples with tension screw geometry. Five different, manufacturing process chains, consisting of the process steps heat treatment, turning, and grinding, were applied. After selected process steps, light and SEM micrographs as well as fatigue experiments were performed. The process itself as well as the process parameters influences the properties of the surface layers and the fatigue behavior in a characteristic manner. For example the variation of the feed rate and cutting speed in the hard-turning process leads to significantly different mechanical properties of the surface layers and residual stress states, which could be correlated with the fatigue behavior. The cyclic deformation behavior of the investigated components can be benchmarked equivalently with stress,strain hysteresis as well as high precision temperature and electrical resistance measurements. The temperature and electrical resistance measurements are suitable for component applications and provide an enormous advantage of information about the fatigue behavior. The temperature changes of the failed areas of the samples with tension screw geometry were significantly higher, a reliable identification of endangered areas is thereby possible. A new test procedure, developed at the Institute of Materials Science and Engineering of the University of Kaiserslautern, with inserted load-free-states during constant amplitude loading, provides the opportunity to detect proceeding fatigue damage in components during inspections. [source] Behaviour of polysorbate 20 during dialysis, concentration and filtration using membrane separation techniquesJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 2 2008Hanns-Christian Mahler Abstract During formulation development of a therapeutic protein, combinations of buffers, pH and excipients need to be tested. As the protein bulk solution used for formulation development usually contains a buffer component at a defined pH and potentially one or more excipients already, this bulk requires to be processed. In case low concentrations of non-ionic surfactants, for example polysorbate 20, are already present in the bulk, the surfactant needs to be removed in lab-scale for further development use. The scope of the work was to study the behaviour of low concentrations of polysorbate 20 during membrane separation processes. The first part focuses on evaluating the behaviour of polysorbate 20 during a dialysis process, whereas the second part analyses concentration changes of polysorbate during a membrane concentration process using a stirred cell. The third part analyses potential membrane absorption of polysorbate at sterilizing-grade filters. In conclusion, it was found that polysorbate could not be significantly reduced during a dialysis process and accumulated during a membrane concentration process in unreproducable manner. During sterile filtration, no significant influence on the concentration of polysorbate was measurable. In any case, it is recommendable to quantify the concentration of polysorbate during critical membrane process steps in pharmaceutical industry. © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:764,774, 2008 [source] A PROCESS ANALYSIS OF GLOBAL TRADE MANAGEMENT: AN INDUCTIVE APPROACH,JOURNAL OF SUPPLY CHAIN MANAGEMENT, Issue 2 2010WARREN H. HAUSMAN This paper describes a new, detailed process model for Global Trade Management (GTM) that contains sufficient detail on cross-border trade processes to estimate the benefits of Information Technology-Enabled Global Trade Management (IT-GTM). Our methodology combines a grounded theory approach with data analysis and analytical modeling. GTM describes the processes required to support cross-border transactions between importers, exporters, their trading partners and governments. IT-GTM is the set of information technologies and software solutions that can be used by companies to carry out their global trading processes in a streamlined manner. We collect data on time reductions for individual trade process steps using IT-GTM and use Critical Path Analysis to calculate the resulting improvements in key metrics such as the Manufacture to Invoice Cycle and Days Sales Outstanding for exporters, and the Order to Receipt Cycle for importers. Under reasonably conservative scenarios the gross savings from IT-GTM amount to 1.7 percent and 0.6 percent of annual sales for exporters and importers, respectively. [source] Physico-enzymatic production of monoacylglycerols enriched with very-long-chain polyunsaturated fatty acidsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2008Ratchapol Pawongrat Abstract BACKGROUND: Monoacylglycerols (MAG) containing polyunsaturated fatty acids (PUFA), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have interesting applications. The enzymatic processing of such MAG directly from fish oils is highly interesting, integrating the processing of MAG and concentration of EPA and DHA. The aim of this study was to develop an efficient enzymatic glycerolysis system together with physical fractionation for the production of PUFA-MAG from tuna oil. RESULTS: Novozym 435 was eventually selected after evaluation together with immobilized lipase AK in a tertiary alcohol-based system. A further evaluation of solvent mixtures involving tertiary alcohols was made, taking ease of operation into consideration. It turned out that a number of mixtures gave a similar performance to that of tert -butanol (TB). Basic reaction parameters were thoroughly evaluated. In the batch reaction system with TB as solvent, the recommended conditions were: glycerol/tuna oil 4:1 (mol/mol), TB/tuna oil 2:1 (wt/wt), 15 wt% Novozym 435, and temperature 40 °C. Under these conditions, the yield of MAG was up to 90% after 3 h incubation. Crude MAG from the production was fractionated to produce MAG with higher EPA and DHA content. Using acetone as solvent at 0 °C led to ca 50% yield of MAG but contained EPA and DHA up to 71% in comparison with ca 30% in tuna oil. CONCLUSION: Potentially practical process steps have been developed for the production of MAG containing a high content of EPA and DHA from natural fish oils with high efficiency and simplicity. Copyright © 2007 Society of Chemical Industry [source] Microreactor Array Assembly, Designed for Diversity Oriented Synthesis Using a Multiple Core Structure Library on Solid SupportMOLECULAR INFORMATICS, Issue 11 2006Alexander Groß Abstract The application of spatially encoded principles in solid phase combinatorial synthesis requires no chemical or physical coding strategies. The resulting products are encoded by their position inside the array and their synthesis history. The advantages of microreactor arrays for solid phase synthesis as one of the embodiments in the field of microreaction technology are discussed. Here, we review the reactor design, necessary process steps, and a strategy for the diversity oriented array synthesis. In particular, the glass-made microreactor and its assembly for 1563 parallel solid phase reactions, which can be performed at temperatures up to 120,°C, are described. Bead loading and liquid handling steps were adapted to this array. The production of large libraries demands suitable synthesis protocols and building blocks. The optimization of appropriate synthesis conditions is a time-consuming process. A multiple core structure library approach for the efficient synthesis of diverse heterocyclic libraries is described. The aim of this work was to prove the feasibility of the glass-microreaction array for massive parallel library synthesis. [source] AlGaN/GaN-based MEMS with two-dimensional electron gas for novel sensor applicationsPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2008F. Niebelschütz Abstract Novel microelectromechanical resonators structures have been realized based on AlGaN/GaN heterostructures, which provide a basis for sophisticated sensor structures. There were grown on SiC substrates confining a two dimensional electron gas (2DEG). By means of the developed etching technology, freestanding resonators were patterned without degrading the sheet carrier concentration and electron mobility of the 2DEG inside the beams, which was confirmed by electrical measurements before and after the various process steps. As actuation and read out principle magnetomotive and piezoelectric effects were used, respectively. Due to the high sensitivity of the 2DEG and the chemical stability of the utilized materials these structures are suitable for chemical and biological sensor applications, where the sensitivity of the 2DEG on the surrounding environment acts as additional sensing signal, for example for simultaneous measurements of the viscosity and pH , value of a nanoliter droplet. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Spatially resolved characterization of silicon as-cut wafers with photoluminescence imagingPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 4 2009Johannes A. Giesecke Abstract The characterization of silicon as-cut wafers is important for process control in solar cell production, since it can serve as starting material quality inspection and give information about a change of material properties caused by different process steps. In particular, spatially resolved characterization tools such as Photoluminescence Imaging (PLI) are useful as an information source. Due to the low signal in a luminescence image of an as-cut wafer a major problem is superimposed laser reflection light if the detection occurs from the illuminated side of the wafer. We present a method which eliminates the spurious reflection contribution by a special image correction technique. The image correction is based on a separate measurement of a reflection topography of the as-cut wafer surface. Additionally we show that for non calibrated luminescence images of as-cut material the bulk lifetime in low quality areas can be estimated by relating PL-intensity in these areas to a saturated PL-intensity value that can be assigned to high quality areas via a simulated curve of relative PL-intensity over minority carrier bulk lifetime. Copyright © 2008 John Wiley & Sons, Ltd. [source] 8% Efficient thin-film polycrystalline-silicon solar cells based on aluminum- induced crystallization and thermal CVDPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 7 2007I. Gordon Abstract A considerable cost reduction could be achieved in photovoltaics if efficient solar cells could be made from polycrystalline-silicon (pc-Si) thin films on inexpensive substrates. We recently showed promising solar cell results using pc-Si layers obtained by aluminum-induced crystallization (AIC) of amorphous silicon in combination with thermal chemical vapor deposition (CVD). To obtain highly efficient pc-Si solar cells, however, the material quality has to be optimized and cell processes different from those applied for standard bulk-Si solar cells have to be developed. In this work, we present the different process steps that we recently developed to enhance the efficiency of pc-Si solar cells on alumina substrates made by AIC in combination with thermal CVD. Our present pc-Si solar cell process yields cells in substrate configuration with efficiencies so far of up to 8·0%. Spin-on oxides are used to smoothen the alumina substrate surface to enhance the electronic quality of the absorber layers. The cells have heterojunction emitters consisting of thin a-Si layers that yield much higher Voc values than classical diffused emitters. Base and emitter contacts are on top of the cell in interdigitated finger patterns, leading to fill factors above 70%. The front surface of the cells is plasma textured to increase the current density. Our present pc-Si solar cell efficiency of 8% together with the fast progression that we have made over the last few years indicate the large potential of pc-Si solar cells based on the AIC seed layer approach. Copyright © 2007 John Wiley & Sons, Ltd. [source] High-rate deposition of epitaxial layers for efficient low-temperature thin film epitaxial silicon solar cellsPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 5 2001Lars Oberbeck Low,temperature deposition of Si for thin-film solar cells has previously been hampered by low deposition rates and low material quality, usually reflected by a low open-circuit voltage of these solar cells. In contrast, ion-assisted deposition produces Si films with a minority-carrier diffusion length of 40,,m, obtained at a record deposition rate of 0.8,,m/min and a deposition temperature of 650°C with a prebake at 810°C. A thin-film Si solar cell with a 20-,m-thick epitaxial layer achieves an open-circuit voltage of 622,mV and a conversion efficiency of 12.7% without any light trapping structures and without high-temperature solar cell process steps. Copyright © 2001 John Wiley & Sons, Ltd. [source] Applying Near-Infrared Spectroscopy in Downstream Processing: One Calibration for Multiple Clarification Processes of Fermentation MediaBIOTECHNOLOGY PROGRESS, Issue 2 2008Licínia O. Rodrigues The use of near-infrared spectroscopy (NIRS) is demonstrated in the first downstream processing (DSP) steps of an active pharmaceutical ingredient (API) manufacturing process. The first method developed was designed to assess the API content in the filtrate stream (aqueous) of a rotary drum vacuum filter. The PLS method, built after spectral preprocessing and variable selection, had an accuracy of 0.01% (w/w) for an API operational range between 0.20 and 0.45% (w/w). The robustness and extrapolation ability of the calibration was proved when samples from ultrafiltration and nanofiltration processes, ranging from 0 to 2% (w/w), were linearly predicted ( R2=0.99). The development of a robust calibration model is generally a very time-consuming task, and once established it is imperative that it can be useful for a long period of time. This work demonstrates that NIR procedures, when carefully developed, can be used in different process conditions and even in different process steps of similar unit operations. [source] The IBUS Process , Lignocellulosic Bioethanol Close to a Commercial RealityCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 5 2008J. Larsen Abstract Integrated Biomass Utilization System (IBUS) is a new process for converting lignocellulosic waste biomass to bioethanol. Inbicon A/S has developed the IBUS process in a large-scale process development unit. This plant features new continuous and energy-efficient technology developed for pretreatment and liquefaction of lignocellulosic biomass and has now been operated and optimized for four years with promising results. In the IBUS process, biomass is converted using steam and enzymes only. The process is energy efficient due to very high dry matter content in all process steps and by integration with a power plant. Cellulose is converted to bioethanol and lignin to a high-quality solid biofuel which supply the process energy as well as a surplus of heat and power. Hemicellulose is used as feed molasses but in the future it could also be used for additional ethanol production or other valuable products. Feasibility studies of the IBUS process show that the production price for lignocellulosic bioethanol is close to the world market price for fuel ethanol. There is still room for optimization , and lignocellulosic bioethanol is most likely a commercial alternative to fossil transport fuels before 2012. [source] | |||||||||||||||||||