Gezielte Nutzung biologischer Systeme

Directed exploitation of biological systems . During the past few decades, our knowledge of molecular process responsible for genetics has increased dramatically. Discovery of the giant molecule deoxyribonucleic acid – abbreviated as DNA – as the carrier of genetic information heralded in a development which nowadays permits us to effect directed changes in the genetic material of an organism. Thus we can provide easily cultured microorganisms with genes which were previously located in a completely different genetic environment. This helps us to obtain high yields of proteins or other substances which were formerly very difficult to obtain. Higher organisms such as animals and plants can also undergo modification of their genetic equipment. This adds a new dimension to the breeding of such species. Above all, genetic engineering provides new insights into the enormously complex interplay of molecules which go to make up a living cell. The resulting understanding of life processes on a molecular level permits recognition of malfunction and therapy of the ensuring disease by new drugs. In addition to these positive aspects, genetic engineering provides scope for conducting experiments whose ethical implications demand very earnest consideration.     

Keeping properties of edible oils—Part I. The use of accelerated tests for assessment of the keeping properties of oils and the value of antioxidants

Assessment of oil quality by two accelerated oxidation tests gave little or no correlation with organoleptic asessment during storage. Improvements in quality of oils refined in the factory, to which antioxidants had been added, are indicated by the accelerated tests but are not reproduced in normal storage. Howver a treatment of the oils with alumina, as a part of the refining process replacing earth bleaching, appears to remove antagonistic factors, and under these circumstances the addition of antioxidant has a pronounced effect.     

Enlargement of the micropores of a caking bituminous coal by controlled oxidation

In a study of the enlargement of pores of coals it has been found that treatment of a bituminous coal (PSOC No. 371, from the Pennsylvania State University Coal Section) with a 5:95 O₂:N₂ stream 4 h at 400 °C increases the surface area as measured by nitrogen adsorption at 77K by a factor of at least 50 to a value 52 m² g^?1. The increase in pore size was accompanied by a 9.7% weight loss. Simultaneously, the area as measured by carbon dioxide at 195K increased from 61 to 136 m² g^?1 and that measured by carbon dioxide at room temperature increased from 125 to 237 m² g^?1. Attempts to enlarge the pores by oxidation with hydrogen peroxide or ozone were unsuccessful. A Pittsburgh coal subject to a small percentage of oxygen in nitrogen or steam at 300 to 400 °C showed a surface area as measured by nitrogen adsorption of less than 1 m² g^?1 both before and after such pretreatment. This same coal with a 5:95 O₂:N₂ stream for 4 h at 450 °C showed a surface area of 110 m² g^?1 measured by nitrogen adsorption at 77K.     

Selective gas transport in miscible PPO-PS blends

The permeation rates of He, CO₂ and CH₄ though miscible blends of polystyrene and poly(phenylene oxide) at 35°C are reported as a function of pressure. Sorption isotherms for CO₂ and CH₄ are also presented. By using ratios of the permeabilities of the pure gases the separation factors for the gas pairs He---CH₄ and CO₂---CH₄ can be estimated. For both pairs the estimated separation factor goes through a prominent maximum, thus indicating that these blends are more permselective than expected from the behaviour of polystyrene and poly(phenylene oxide). This stems from mobility considerations rather than solubility effects and a qualitative free volume argument is proposed as an explanation. The sorption and transport data have been interpreted and correlated using the dual sorption-mobility models developed previously for glassy polymers. Since the commercial polystyrene used contained a small amount of mineral oil to improve flow behaviour, the effect of this additive on polystyrene properties was explored in some detail.     

A new LCL-lens array with electrodes of interlaced structure to be applied for auto-stereoscopic 3D displays

A new design of the liquid crystal lenticular (LCL) lens array with interlaced electrodes is proposed to realize an auto-stereoscopic 3D display. The structure of interlaced electrodes aims to generate a desired non-uniform electric filed to improve the focusing ability of the LCL-lens array with lower voltage drives. This paper is organized as first to describe the design criteria of a lenticular lens sheet for wide extended graphics array LCD panel. Based on the designed lenticular lens array, an LCL-lens array with proposed interlaced electrodes is next designed. The fabrication and the detailed structure are given. A series of experiments are then conducted and successfully verify the focusing capability and desired 3D display functions, that is, to separate two images to right and left eyes. Also, the developed auto-stereoscopic 3D display is able to adapt to varied viewer locations with favorable imaging quality.     

Design and realization of a high resolution (640 × 480) SWIR image acquisition system

A new image acquisition system module for extracting signals of high-resolution short wave infrared (SWIR) from a focal plane array (FPA) is presented in this study. The short wave infrared (SWIR—with wavelength about 900–1,700 nm) images have been proven its unique values in many applications such as military, semiconductor inspection and aviation security. The designs for the SWIR data acquisition system module consists of digitization and acquisition of FPA signals, design of synchronous dynamic random access memory controller and real-time image signal transformation and display. Three major steps involved towards a successful SWIR module—(1) Selection of hardware ICs according to specification for the FPA; (2) Design of a timing generator for the image acquisition system to control FPA and other ICs by Verilog HDL programming; (3) Integrate the individual modules on a PCB. The SWIR image output signals are successfully generated in the format of National Television System Committee (NSTC), which can be displayed on a common NTSC monitor, flat panel displays with an AV input terminal or a CRT display in a favorable speed of frame rate at 30 per second.     

Chemistry of miscible polycarbonate–copolyester blends

Blends of polycarbonate and the copolyester based on 1,4-cyclohexanedimethanol and a mixture of terephthalic and isophthalic acids are known to be completely miscible. This study was concerned with various chemical events which may occur in this system, particularly during melt processing. Degradation reactions were studied by both TGA and dilute viscometry techniques, and some indications of component interaction were noted. The residual titanium catalyst from the copolyester formation was found to produce color formation by interaction with phenolic end groups in the polycarbonate and to promote interchange reactions. Both events could be suppressed by deactivation of the residual catalyst with appropriate additives. An indication of the extent of interchange reactions was obtained by following the crystallizability of the copolyester component using differential scanning calorimetry.     

Preparation of Silicon Carbide/Aluminum Nitride Ceramics Using Organometallic Precursors

Solid solutions of 2H -SiC/AlN can be prepared at temperatures less than 1600°C by rapid pyrolysis ("hot drop") of mixtures of [(Me₃Si)_0.80((CH₂=CH)MeSi)_1.0(MeHSi)_0.35] _n (VPS) or [MeHSiCH₂] _n (MPCS) with [R₂AlNH₂]₃, where R=Et, i -Bu or simply by slow pyrolysis of the precursor mixture in the case of [Et₂AlNH₂]₃. In contrast, slow pyrolysis of mixtures of VPS or MPCS with [ i -Bu₂AlNH₂]₃ yields a composite of 2 H -AlN and 3 C -SiC at 1600°C, which transforms into a single 2 H -SiC/AlN solid solution on heating to 2000°C. The influences of the nature of the precursor and processing conditions on the structure, composition, and purity of the SiC/AlN materials are discussed.     

Evaluation of four steering wheels to determine driver hand placement in a static environment

While much research exists on occupant packaging both proprietary and in the literature, more detailed research regarding user preferences for subjective ratings of steering wheel designs is sparse in published literature. This study aimed to explore the driver interactions with production steering wheels in four vehicles by using anthropometric data, driver hand placement, and driver grip design preferences for Generation-Y and Baby Boomers. In this study, participants selected their preferred grip diameter, responded to a series of questions about the steering wheel grip as they sat in four vehicles, and rank ordered their preferred grip design. Thirty-two male participants (16 Baby Boomers between ages 47 and 65 and 16 Generation-Y between ages 18 and 29) participated in the study. Drivers demonstrated different gripping behavior between vehicles and between groups. Recommendations for future work in steering wheel grip design and naturalistic driver hand positioning are discussed.     

Measuring the bulk flow properties of PVC resins

The flow characteristics of PVC resin are often judged by measuring the time required for a given amount of dry resin to flow through a standard funnel. However, considerable variation in test results have been found between laboratories though the test is conducted well within the procedural limits of ASTM 1895-69, “Apparent Density, Bulk Factor and Pourability of Plastic Materials.” An examination has been made of the effects of funnel hole size, funnel alignment, its type metal and wall surface smoothness, filling technique, static generated, and degree of vibration. It was found that six of these seven variables need critical control, while one (alignment) has no measurable effect. It is suggested that the data presented be used for the development of an improved ASTM test for measuring the flowability of PVC resins.