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The work is devoted to research and intensification of the process of boiling of solutions with different viscosities in evaporators of a tubular type with forced circulation and a drift boiling zone. The main factors that influence the change in the hydraulic resistance of the heating chamber under various operating conditions and the dependence of the loss on vapor content are determined on the developed laboratory device. The optimum value of the circulation velocity of the working solution at various temperatures and the boiling zones is also found in the article

Due to its negative impact on the yield and quality of stored grains, the aim of this research was to study the influence of Rhyzopertha dominica F. on rheological properties of wheat flour obtained from grains infested by examined pest. A rheological laboratory device - Mixolab was employed in order to simulate the production process of bread (from the beginning of dough mixing until the end of bread baking). Wet gluten and gluten index, as significant flour quality parameters, were also determined. The flour of wheat varieties Planeta and Kruna was used in these experiments. The samples of both varieties infested with R. dominica (infested samples) were characterized and compared to their uninfested counterparts (control samples). Infested samples expressed a lower gluten index content, greater weakening of the gluten network upon mixing and heating, as well as lower starch gelatinization viscosity in comparison to control samples. Changes in the gluten index value were more pronounced in Planeta variety which was characterized with a higher degree of infestation. Determined changes in rheological properties of infested wheat were mainly dependent on a degree of infestation. However, a varietal dependency on the intensity of changes in technological quality cannot be neglected.

In this study a thermal desorption procedure (HgTPD) was used to identify mercury species in samples of gypsum obtained from wet flue gas desulphurization plants (WFGD). Gypsum from industrial coal combustion power plants and gypsum from a laboratory device that simulates mercury retention in the WFGD process were studied. It was concluded that mercury sulphide (HgS) is the mercury species present in WFGD gypsums unless an additive is used. Mercury speciation in this kind of residue can contribute to a better understanding of the reaction and adsorption behaviour of mercury species in the WFGD process and provide a deeper knowledge of the environmental impact caused by the disposal or reuse of these Hg-containing residues., The financial support for this work was provided by the project CTM2011-22921. The authors thank the Spanish Research Council (CSIC) for awarding Ms. Marta Rumayor a JAE-predoc fellowship.

The effectiveness of the removal process of milk soil was studied using a laboratory device called bath-substrate-flow and three different types of milk: sheep, skimmed cow, and milk for infants. Experiments were performed using different surfactants and operation conditions. The washing efficiency was related to the temperature of the process, type of soiling agent and wash-bath composition. The highest detergency in all cases was detected at high pH levels with surfactants. The results show that the cleaning of these soils differed for each type of milk and depended on the composition of the residue formed. The use of specific surfactant formulations for each soiling agent under the appropriate conditions proved to be a useful option to reduce the cleaning times for clean-in-place processes of milk foulants in the dairy industry, guaranteeing cleaning with a lower environmental and economic impact over the final products.

There are a number of challenges that need to be overcome in order to stimulate more synthesis chemists to adopt continuous-flow chemical processing techniques. By way of example, the use of cryogenic consumables to cool reactions is impractical on scale or over extended reaction times. Here, a solution to the problem is described with the development of a convenient laboratory device that offers chemists the benefits of continuous flow processing using an accurate thermal energy transfer block which provides long-term reaction stability and is free from water ingress.

The purpose of this work is to quantify the energetic interest of convective and intermittent drying process of natural products. This drying mode has been achieved within a climatic tunnel blower. This laboratory device permitted us to achieve several tests for different conditions of the apple slices drying. In the intermittent case, a variation of the air temperature and air velocity values permitted us to find the most economic velocities for the drying of the apple thin slices. The numerical simulations in the intermittent tests, give us more information on what really happens to the product during periods of interruption. The drying kinetics at the resumption increases with the air temperature. Then, we gain in energy and in overall drying time. These studies show the considerable advantages of the intermittent drying of agricultural products and confirm the preservation of their qualities and the reduction of the drying time.

The origin of microscopically-amorphous organic matter (AOM) is problematic. It has been extensively studied because it is the dominant kerogen constituent in petroleum source rocks. Although microbes are widespread in natural environments, they are commonly associated only with marine AOM derived from phytoplankton. In this study, we have selected terrestrial and marine samples with various microbial inputs in order to decipher the role of microbes in AOM composition. A specially-tailored laboratory device has been used for determining the effect of oxygen- and light-depleted conditions on recent microbial mats for a duration of three years. This experiment aimed at reproducing conditions existing in nature at the water–sediment interface. This research has permitted the characterization of AOM according to its biological origin. Two different types of AOM have been observed, i.e., gelified and granular types. They are related respectively to microbial reworking of terrestrial fragments and primary microbial populations. Moreover, bacterial bodies constitute the ubiquitous, strongly fluorescent material, whereas extracellular polymeric substances (EPS) surround bacteria and show a weaker fluorescence. Consequently, this study on modern OM has unravelled the amorphization process of specific organic particles leading to AOM classically encountered in fossil sediments. This has considerable implications for palaeoenvironmental reconstructions associated with the origin and preservation of OM.

Die Forschungsarbeiten hatten das Ziel, einen Prozess zu entwickeln, der die Erzeugung einer hohen elektrischen Durchschlagsfestigkeit in kurzester Prozesszeit auf Aluminiumbandern ermoglicht. Um in den Versuchen die Prozessparameter in einem breiten Bereich zu variieren, wurde gemeinsam mit der Fa. Steinert Elektromagnetbau GmbH Koln eine flexible diskontinuierliche Laboranlage konzipiert. Durch die Anwendung des Flussigleiterprinzips lies sich in diesem Equipment die in kontinuierlichen Anlagen praktizierte festkontaktfreie Anodisierung von Aluminiumbandern nachempfinden. Die Entwicklungsarbeiten konzentrierten sich auf die Gestaltung der Stromform. Anhand der Ergebnisse wird deutlich, dass es durch geeignete elektrische Parameter (Stromformen) in Verbindung mit einer entsprechenden Nachbehandlung moglich ist, hochste Durchschlagsspannungen in kurzester Prozesszeit zu erreichen. Die nach der neuen Technologie (Stromform TUCAL) erzeugten Schichten weisen zudem eine hohere Porendichte als die konventionell hergestellten auf, was sich in einer hoheren Duktilitat (geringeren Rissanfalligkeit) niederschlagt. Process for anodizing of aluminum stripes with high electrical breakdown voltage The Aim of the research was to develop an anodizing process for generating a high breakdown voltage on aluminum stripes in the shortest processing time possible. In order to vary process parameters in a wide range, a flexible discontinuous anodizing laboratory device was designed in cooperation with Steinert Elektromagnetbau GmbH Koln. By means of the liquid contact method, conditions equal to non-solid contact anodizing of aluminum stripes in continuous laboratory devices were simulated. The research was focused on the development of the current pulse shape. The results show that the highest possible breakdown voltages can be achieved in a short processing time using suitable electrical parameters (current pulse shape) and the appropriate post-treatment. The films generated by the new technology (current pulse shape referred to as “TUCAL”) reveal a higher pore density than conventional layers. This results in a higher ductility (less tendency for cracking).

Latex immunoagglutination assay (LIA), also known as latex agglutination test or turbidimetric/nephelometric particle immunoassay, has been popular in clinical diagnostics due to its simplicity. Lab-on-a-chip, a miniaturized laboratory device made with semiconductor manufacturing technologies, has a strong potential in point-of-care testing (POCT). Demonstration of LIA in lab-on-a-chip format, both microchannel and microdrop types, has not been fully successful due to the mixing problem inherent in lab-on-a-chip. In this article, current technical hurdles for conducting LIA in lab-on-a-chip are addressed, such as mixing, optical detection, and device reusability, and possible solutions are suggested. In addition, potential applications are presented, including medical/veterinary diagnostics, detection of waterborne pathogens, and controlled environment agriculture.

Background: The StatSensor® Xpress-i™, a point-of-care system for blood creatinine measurement, offers patients the possibility of self-monitoring creatinine. In this study, the analytical performance of the StatSensor® for both detecting current renal function and monitoring renal (dys)function in kidney transplant patients was examined. Methods: Accuracy of the StatSensor® with capillary and venous whole blood was evaluated and compared to an isotopic dilution mass spectrometry (IDMS)-traceable enzymatic creatinine test in venous serum (n=138). Twenty Li-heparin samples were compared to the IDMS reference method performed by a Joint Committee for Traceability in Laboratory Medicine (JCTLM)-listed reference laboratory (RfB, Bonn, Germany). To evaluate StatSensor®'s suitability to monitor kidney function, both venous and capillary samples were obtained in 20 hospitalized transplantation patients. Venous samples were analyzed with an IDMS-traceable enzymatic test, capillary samples were measured using the StatSensor®. For all 2-day intervals, percentage change in creatinine was compared between both methods. Results: The StatSensor® did not meet total allowable error criterion of 6.9%. Average overall CVa for the StatSensor® was 10.4% and 5.2% for capillary and venous whole blood results, respectively. Overall CVa for the central laboratory serum creatinine method was

Cyclofructans (CFs) and their derivatives have recently been proven to be efficient chiral selectors (CSs) for the enantioseparation of several analytes in CE, HPLC, and GC. In this study, the chiral separation ability of a number of native and derivatized CFs was examined in CE. Particularly, six different CFs, with different derivatization groups and cavity sizes [native CF-6 and CF-7, isopropyl cyclofructan-6 (IPCF-6), IPCF-7, sulfated cyclofructan-6 (SCF-6), and SCF-7] were used as CSs for the enantioseparation of huperzine A, warfarin, and coumachlor. Almost all of the examined CFs, except from SCF-6 & -7, demonstrated relatively low and sometimes no chiral separation ability for huperzine A. In an effort to improve both resolution and efficiency, the chiral ionic liquid D-Alanine tert butyl ester lactate (D-AlaC4Lac) was added into the BGE. In most of the cases, the combination of CF with D-AlaC4Lac resulted in an improvement in peak efficiency and/or resolution. When CF-6 was utilized with D-AlaC4Lac, a resolution of 1.4 was obtained, while the use of IPCF-6/D-AlaC4Lac provided a baseline enantioseparation. Although the combination of SCF-7 and 40 mM D-AlaC4Lac did not affect resolution, it dramatically increased peak efficiency from 24 000 to 117 000. In the case of warfarin and coumachlor, IPCF-6 and IPCF-7 proved to be the most effective CSs. It is, therefore, concluded that the size of the cavity and the CF derivatization are the key parameters for the chiral separation capability. It is also clear from this study that D-AlaC4Lac is necessary for improved peak efficiencies and resolutions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. 36 24 3061 3068 Tradenames: AgilentG1600A Capillary Electrophoresis Syste, Agilent, Greece Manufacturers: Agilent, Greece Cited By :8

The backscattering technique was applied to materials of steam generator pipes of fossil fired plants in order to study the corrosion layers with respect to elemental amounts and depth structure. The samples were taken from plants and also from treatment in a laboratory device for the simulation of material stress. Using 7.6 MeV He-ions the oxide layer of a sample of a long time operated steam generator pipe was analyzed. Further three samples heated in a laboratory device in air show the initial state of corrosion. A damaged pipe of a coal fired plant was also investigated using 2 MeV He-ions in order to determine the elemental amounts in the oxide layer and in the ash layer at the fire side. The results allowed to draw conclusions for further plant operations.

This study evaluated the effect of microwave radiation on the fluid permeability and compression strength parallel to the grain of beech false heartwood. European beech (Fagus sylvatica L.) was selected, and samples of false heartwood with dimensions of 30×20×20 mm3 were used. The microwave treatment was carried out in a laboratory device at a frequency of 2.45 GHz. The testing samples were divided into three groups (untreated, treated at 20-s intervals, and treated at 30-s intervals). The permeability was measured in the axial direction using distilled water. The coefficient of specific permeability was calculated using Darcy’s law. The results showed that the coefficient of specific permeability increased by up to 159% in comparison with untreated samples. The compression strength parallel to the grain decreased by up to 15%.

In this paper, rheological characteristics of flour are determined with Brabender farinograph. Brabender Farinograph is the most widely used laboratory device to evaluate the quality of flour, in batter, with which the rheological characteristics of flour is determined by measuring and recording gluten strength and endurance. With farinograph records the dough structure changes over time and obtaining data about: Absorption of flour, flour power (its ability to form a dough with rheological properties appropriate to flow operations technology), forming time of the dough, the degree of stability and soaking, the consistency of dough during this time. Analyzing the data presented on farinograph curves, were extracted the values of the dough development time (min), stability (min), softening degree (FU), consistency (FU), the absorption capacity of flour (%) farinograph index of the dough ..

The development of helium leak detectors was stimulated by the requirement for the detection of very fine leakages in vacuum devices. The idea of using a small mass spectrometer together with the choice of helium as a tracer gas turned out to be very successful. The helium leak detector—first a great hulking machine—developed into a variety of specialized units and, in the last few years, portable versions became possible. The basic specifications of leak detectors will be described in their relevance and how the so called counterflow technique revolutionized the performance by making liquid nitrogen dispensable will be discussed. The real industrial unit was finally possible because all the complicated jobs of tuning, zeroing, ranging and calibrating are nowadays done by the built-in microprocessor. As examples, a testing machine for semiconductor devices and a detection module for industrial testing are described. Looking at the future, two perspectives show up: for vacuum leak detection more specialized units with less or smaller pumps operating oilfree and in higher pressure regions are the developmental trend. For overpressure leak detection new principles without pumps and mass spectrometers (membrane techniques?) could be a possible direction of development.

PVD- and CVD-layers were analysed by GDOES using a homemade laboratory device and the commercial Spectrumat 1000. The presented examples demonstrate the many possibilities of GDOES and give information about the further development of this analytical technique.

The paper deals with the absorption spectra of bilirubin solutions, patient blood plasma with jaundice manifestations with a different degree of disease and whole blood. Using as an analysis base the dependencies of blood plasma absorption spectra on bilirubin concentration in this blood there has been proposed the method of disease diagnostics with jaundice manifestations, and there has been realized the corresponding portable laboratory device, the functioning of which is based on registering the radiation propagated through the ear lobule.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Considering the insecticidal effect of modified Atmospheres as an alternative technique to synthetic chemicals, a compact and low–cost laboratory controlled atmosphere device was developed and tested. Device consisted of gas cylinders and regulators, a gas mixer, rotameters, gas sampling ports, relative humidity unit, a temperature controlled environment and a gas chamber. Tests were carried out to determine the efficacy of the device by exposing adults of Tribolium confusum J. du Val and Callosobruchus maculatus (F.) to ternary mixtures of (60% CO2: 8% O2: 32% N2, 70% CO2: 4% O2: 26% N2, and 80% CO2: 1% O2: 19% N2) at seven exposure times (12, 24, 36, 48, 72, 96 and 120 h), relative humidity (r.h.) of (65, 75and 85%), constant temperature of 30°C, flow of rate 50 ml/min, and operating pressure of 40 kPa. Results showed that device can maintain CO2, O2 and r.h. levels used in the investigation within 2, 1.5 and 3 % of the set points respectively and can generate mixtures of gases CO2, O2 and N2 ranging from 0 – 100%. Atmosphere containing 80% CO2, 1% O2 and 29% N2 was more lethal than atmospheres containing 70% CO2, 4% O2 and 26% N2 or 60% CO2, 8% O2 and 32% N2. Also atmospheres humidified to 65% r.h. were generally more lethal than those humidified to 75 and 85%. Atmosphere with 80% CO2, 1% O2 and 19% N2 caused highest mortality when 100% mortality of T. cofusum was achieved in 72 h compared to 24 h which was needed to obtain 100% mortality of C. maculatus adults.

The results of experiments concerning detection of alcohol vapors in car cabins using a laboratory device, which was developed and built at the Institute of Optoelectronics at the Military University of Technology, are described. The work is a continuation of the investigations presented in an earlier paper. On the basis of those results, the whole device was designed and built. Then it was investigated using a car with special system simulating a driver under the influence of alcohol. To simulate the appropriate concentration of alcohol in human blood, a special method of generation of alcohol vapor was developed.

A biosensor for rapid and reproducible measurements of inhibitors of nitrification in environmental samples has been developed. The biosensor is mainly designed to be used for wastewater control and consists of a Clark oxygen probe as a transducer and an immobilised mixed nitrifying culture as the microbial component. The measuring principle is based on the direct determination of bacterial metabolic activity by measuring the oxygen consumption rate of the microbial immobilisate. Both the prototype of a laboratory device and a field device have been realised. The laboratory device can be used to determine the nitrification inhibiting effect of individual chemical compounds as well as of environmental samples. The field device was constructed for on-line monitoring of inhibitors in sewage systems.

Dry-formed networks of cellulose fibers, produced with a laboratory device, have been impregnated with aqueous solutions of poly(vinyl alcohol) or solutions of poly(vinyl acetate) in acetone. In both cases, the strength and stiffness of the networks increase several times compared with the unmodified structure. When aqueous solutions are used, it appears that a minimum amount of poly(vinyl alcohol) is required (ca. 2 wt %) to increase the strength appreciably, but when poly(vinyl acetate) dissolved in acetone is used, as a binder, the strength improves even at the lowest level of polymer addition. For the systems studied here, the elongation at rupture increased with increasing polymer concentration. In most cases, the amount of polymer in the network structure was less than 10 wt %. Some results from impregnations using other polymeric systems, e.g., latices, are also reported.

An airborne flame photometer for the identification of large sodium-bearing aerosols from aircraft is briefly described. This instrument is a modified form of a laboratory device which has been used to count sodium particles. A rough calibration of the flame photometer, in terms of the total amounts of sea-salt in marine air, is discussed. Preliminary observations in trade-wind areas are given and an interesting concentration of sodium in cumulus clouds is indicated.

A simple laboratory device is described which allows the double distillation of water in a continuous and automatic way in order to produce particularly pure water. The water thus obtained has a mean specific conductivity of 0.5 × 10-6 ohm-1cm.-1 at 25° c.