Toward integrated product and process life cycle planning—An environmental perspective

Life cycle engineering (LCE) is a key concept for promoting environmentally sustainable practices among manufacturing firms. A major hurdle in the implementation of LCE is the lack of a systematic and strategic method to design or plan an entire product life cycle. To address this issue, this keynote provides a framework for life cycle development and proposes the concept of life cycle planning. This paper aims to provide explicit and systematic methodologies for life cycle planning by reviewing this research area. Practical cases that employ life cycle planning are also illustrated. Finally, some research directions are suggested.     

Production of 1‐Octanol from n‐Octane by Pseudomonas putida KT2440

A two‐phase biotransformation process for selective hydroxylation of n‐octane to 1‐octanol via Pseudomonas putida KT2440 harboring heterologously expressed P450 monooxygenase from Mycobacterium marinum is presented. Maximum cell‐specific conversion rates of 12.7 mg_octanol g_CDWh^–1 were observed not only in shaking flasks but also in 3.7‐L‐bioreactor studies. The bioreactor experiments were performed avoiding explosive gas mixtures by lowering volumetric power input, aeration rates and substrate concentrations. Based on a stoichiometric network of P. putida KT2440 topological studies were carried out. As a conclusion, potential limitations of NAD(P)H and/or ATP supply at production conditions can be excluded. Hence, the great potential of the host for further increasing conversion is outlined.     

Trans-18:1 acid content and profile in human milk lipids. Critical survey of data in connection with analytical methods

This study presents an in-depth, critical survey of the current knowledge about trans- 18:1 acid content and profile in human milk lipids. Emphasis is placed on the analytical methods employed to quantitate trans- 18:1 acids, most of which lead to imprecise quantitative data. It is demonstrated that data obtained by single gas-liquid chromatography (GLC) on polar capillary columns are underestimates by 25–40%. Several experiments indicate that the total content of trans-18:1 acids in human milk is directly related to the quantities ingested the previous day(s), provided no gross weight loss occurs during breast-milk feeding. Equations have been proposed to describe this relationship, and apparently the percentage of trans-18:1 isomers, relative to total fatty acids, is approximately three-fourths the quantity (in g) ingested by lactating mothers. That is, the determination of the trans-18:1 acid percentage in human milk is a convenient means to estimate trans-18:1 acid consumption by corresponding populations. Adapted methods (i.e., silver-ion thin-layer chromatography, coupled with GLC on long polar capillary columns) allow accurate quantitation of most individual trans- 18:1 acids, more particularly of the trans-Δ16 isomer. This determination, along with a knowledge of the distribution of individual isomers in ruminant fats and partially hydrogenated oils, is a convenient means to estimate the relative contribution of these two dietary sources to the distribution of individual trans-18:1 isomers in human milk lipids. A comparison of human milk and infant formulas is made with regard to trans-18:1 acid content and profile. Important differences are noted between data from European countries and from North America.     

Technology trends of high‐pressure mercury short‐arc lamps for projection systems

Abstract— We will discuss the advantages and limitations of ac and dc lamp technology for microdisplay‐based projection systems. The performance of the lamp in terms of brilliance and thermal robustness together with the potential lamp lifetime for ac and dc lamps will be discussed. ac and dc lamp designs will be evaluated to judge their potential for future improvements in terms of usable projector lumens.     

Controlled-release behavior of diphenhydramine hydrochloride loaded neutral microgranules and coated using ethylcellulose water dispersion

The development of a loading method of a water-soluble drug using aqueous binding solution to produce microgranules that were then coated with an aqueous ethylcellulose dispersion to sustain drug release is described. The results, in terms of drug used, showed that besides the fluidized bed parameters, the amount of drug dissolved in the binder solution plays an important role in obtaining a satisfying result during the spraying process. Thus, it seems necessary to determine the critical concentration above which the material started to adhere to the interior of the fluidization column, and the possibility of drug layering onto carrier material is aggravated. ANOVA of the time parameter for release of 63.2% of total drug (td) value showed significant influence of ethylcellulose (Aquacoat ECD-30) and dibutyl sebacate concentration on diphenhydramine hydrochloride (DPH) release. The dissolution rate decreased with an increase in polymer concentration. The diffusional exponent n of the Peppas equation indicated that the DPH release kinetic was non-Fickian but approached Fickian diffusion, particularly at higher coating levels.     

Analysis of cationic surfactants by microbore high-performance liquid chromatography-electrospray mass spectrometry

In the work reported here, a state-of-the-art analytical method for the quantitative analysis of cationic surfactants in environmental matrixes is described. High-performance liquid chromatography on-line coupled via an electrospray interface to a mass spectrometer (HPLC-ESP-MS) is used for the determination of ditallowdimethylammonium chloride (DTDMAC) and two of its most important substitution products, diethylester dimethylammonium chloride (DEEDMAC) and Diesterquaternary (DEQ). Using the analytical method developed in our laboratory, it is possible to determine single homologues of these surfactants as well as the first hydrolysis products of DEQ and DEEDMAC. In combination with our extraction procedure, which is based on ion-pair extraction, cationic surfactants were determined in environmental samples (sewage influent, sewage effluent, river water); concentrations ranged from 0.4 to 140 μg/L. The linear dynamic range of the HPLC-ESP-MS method, which is an injected amount between 0.4 and 30 ng, is well suitable for the analysis of these samples, as well as the performance of the quantification through external standards.     

A New Fast-Response Current Control Scheme for Line-Controlled Converters

The drawbacks of closed-loop current control for line- controlled converters are eliminated by generating close to optimal firing pulses in a feedforward channel. The steady-state and dynamic nonlinearities of the converter and the dc motor load are compensated. A standby closed-loopcurrent controller is activated only in the presence of disturbances. Experimental results show excellent dynamic performance at all operating points of a noncirculating current four quandrant drive.     

Organic Electrochemical Transistors Based on the Conjugated Polyelectrolyte PCPDTBT-SO3K (CPE-K)

PCPDTBT-SO₃K (CPE-K), a conjugated polyelectrolyte, is presented as a mixed conductor material that can be used to fabricate high transconductance accumulation mode organic electrochemical transistors (OECTs). OECTs are utilized in a wide range of applications such as analyte detection, neural interfacing, impedance sensing, and neuromorphic computing. The use of interdigitated contacts to enable high transconductance in a relatively small device area in comparison to standard contacts is demonstrated. Such characteristics are highly desired in applications such as neural-activity sensing, where the device area must be minimized to reduce invasiveness. The physical and electrical properties of CPE-K are fully characterized to allow a direct comparison to other top performing OECT materials. CPE-K demonstrates an electrical performance that is among the best reported in the literature for OECT materials. In addition, CPE-K OECTs operate in the accumulation mode, which allows for much lower energy consumption in comparison to commonly used depletion mode devices.