39 research outputs found

    EVALUATION OF ECONOMIC EFFICIENCY OF PROCESS IMPROVEMENT IN FOOD PACKAGING

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    Abstract HRON, J., MACÁK, T., JINDROVÁ, A.: Evaluation of economic effi ciency of process improvement in food packaging. Acta univ. agric. et silvic. Mendel. Brun., 2012, LX, No. 4, pp. 115-120 In general, we make gains in process by the three fundamental ways. First, we defi ne or redefi ne our process in a strategic sense. Second, once defi ned or redefi ned, we commence process operations and use process control methods to target and stabilize our process. Third, we use process improvement methods, as described in this paper, along with process control to fully exploit our process management and/or technology. Process improvement is focused primarily in our subprocesses and sub-subprocesses. Process leverage is the key to process improvement initiatives. This means that small improvements of the basic manufacturing operations can have (with the assumption of mass repetition of the operation) a big impact on the functioning of the whole production unit. The complexity within even small organizations, in people, products, and processes, creates signifi cant challenges in eff ectively and effi ciently using these initiatives tools. In this paper we are going to place process purposes in the foreground and initiatives and tools in the background as facilitator to help accomplish process purpose. Initiatives and tools are not the ends we are seeking; result/ outcomes in physical, economics, timeliness, and customer service performance matter. In the paper process boundaries (in a generic sense) are set by our process purpose and our process defi nition. Process improvement is initiated within our existing process boundaries. For example, in a fast-food restaurant, if we defi ne our cooking process around a frying technology, then we provide process improvements within our frying technology. On the other hand, if we are considering changing to a broiling technology, then we are likely faced with extensive change, impacting our external customers, and a process redefi nition may be required. The result / aim of the paper are based on the example of the process improving of a food packaging quality. Specifi cally, the integration of two approaches: statistical process control (SPC) and quality control based on stochastic principle. Both approaches are represented in the quality control of food packaging. Based on the obtained data set of weld strength packaging fi lms (in units of MPa) was tested by the statistical hypothesis that innovation in the implementation of the weld has a positive impact on the quality of the fi nished weld. From basic data analysis, which focused on the assessment of normality in the distribution of values of the parameter using the Shapiro-Wilkes test it can be seen (o

    ALD growth of MoS2 nanosheets on TiO2 nanotube supports

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    Two-dimensional MoS2 nanostructures are highly interesting and effective in a number of energy-related applications. In this work, the synthesis of ultra-thin MoS2 nanosheets produced by the thermal Atomic Layer Deposition (ALD) process is reported for the first time using a previously unpublished set of precursors, namely bis(t-butylimido)bis(dimethylamino)molybdenum and hydrogen sulfide. These nanosheets are homogenously deposited within one-dimensional anodic TiO2 nanotube layers that act as a high surface area conductive support for the MoS2 nanosheets. The decoration of high aspect ratio TiO2 nanotube layers with MoS2 nanosheets over the entire nanotube layer thickness is shown for the first time. The homogeneous distribution of the MoS2 nanosheets is proved by STEM/EDX. This resulting new composite is employed as anode for Li-ion microbatteries. The MoS2-decorated TiO2 nanotube layers show a superior performance compared to their counterparts without MoS2. Compared to electrochemical performance of pristine TiO2 nanotube, a more than 50% higher areal capacity and a coulombic efficiency of 98% are obtained on the MoS2 decorated TiO2 nanotube layers, demonstrating clear synergic benefits of the new composite structure

    TiO2 Nanotube Layers Decorated with Al2O3/MoS2/Al2O3 as Anode for Li-ion Microbatteries with Enhanced Cycling Stability

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    TiO2 nanotube layers (TNTs) decorated with Al2O3/MoS2/Al2O3 are investigated as a negative electrode for 3D Li-ion microbatteries. Homogenous nanosheets decoration of MoS2, sandwiched between Al2O3 coatings within self-supporting TNTs was carried out using atomic layer deposition (ALD) process. The structure, morphology, and electrochemical performance of the Al2O3/MoS2/Al2O3-decorated TNTs were studied using scanning transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and chronopotentiometry. Al2O3/MoS2/Al2O3-decorated TNTs deliver an areal capacity almost three times higher than that obtained for MoS2-decorated TNTs and as-prepared TNTs after 100 cycles at 1C. Moreover, stable and high discharge capacity (414 mu Ah cm(-2)) has been obtained after 200 cycles even at very fast kinetics (3C)

    The violent youth of bright and massive cluster galaxies and their maturation over 7 billion years

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    In this study, we investigate the formation and evolution mechanisms of the brightest cluster galaxies (BCGs) over cosmic time. At high redshift (z ∼ 0.9), we selected BCGs and most massive cluster galaxies (MMCGs) from the Cl1604 supercluster and compared them to low-redshift (z ∼ 0.1) counterparts drawn from the MCXC meta-catalogue, supplemented by Sloan Digital Sky Survey imaging and spectroscopy. We observed striking differences in the morphological, colour, spectral, and stellar mass properties of the BCGs/MMCGs in the two samples. High-redshift BCGs/MMCGs were, in many cases, star-forming, late-type galaxies, with blue broad-band colours, properties largely absent amongst the low-redshift BCGs/MMCGs. The stellar mass of BCGs was found to increase by an average factor of 2.51 ± 0.71 from z ∼ 0.9 to z ∼ 0.1. Through this and other comparisons, we conclude that a combination of major merging (mainly wet or mixed) and in situ star formation are the main mechanisms which build stellar mass in BCGs/MMCGs. The stellar mass growth of the BCGs/MMCGs also appears to grow in lockstep with both the stellar baryonic and total mass of the cluster. Additionally, BCGs/MMCGs were found to grow in size, on average, a factor of ∼3, while their average Sérsic index increased by ∼0.45 from z ∼ 0.9 to z ∼ 0.1, also supporting a scenario involving major merging, though some adiabatic expansion is required. These observational results are compared to both models and simulations to further explore the implications on processes which shape and evolve BCGs/MMCGs over the past ∼7 Gyr

    Ochrana hematitových elektrod pomocí krycích TiO2 vrstev vytvořených ALD

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    Iron (III) oxide, in the form of hematite (alpha-Fe2O3), is a n-type semiconductor which is photoactive in the visible spectral region. Therefore, use in photoelectrocatalysis and photoassisted water electrolysis may be suggested. For such implementations, stability of contacts with liquid phases is mandatory. Hematite is stable in alkaline media but less stable in acidic media. For the first time the coverage of porous photoactive Sn doped hematite by thin capping layers of TiO2, deposited by Atomic Layer Deposition (ALD) and its impact on photocurrent and chemical stability of hematite is shown. The nominal thicknesses of the TiO2 ALD coatings were 0.5, 2 and 7.5 nm. The presence of the TiO2 coatings was evidenced by X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy (HR-TEM) and scanning TEM coupled with energy dispersive X-ray (EDX) spectroscopy. HR-TEM analyses revealed that the TiO2 capping layers were amorphous and conformal. Exposure of uncovered hematite layers to 1 M sulfuric acid led to a nominal dissolution rate of 0.23 nm/h which was halved when a TiO2 ALD coating (7.5 nm thin) was applied. Due to mismatch of the valence band positions of the two semiconductors, photocurrents were strongly diminished as the capping layer thickness was increased. Post calcination of as deposited ALD films on hematite resulted in an increase of photocurrent, which only exceeded photocurrents of pristine hematite when the ALD thickness was not more than 0.5 nm.Oxid železitý ve formě hematitu (α-Fe2O3) je polovodič n-typu a je fotoaktivní ve viditelné spektrální oblasti. Proto lze využít ve fotoelektrokatalýze a fotoasistovaném rozkladu vody. Pro tyto využití je důležitá jeho stabilita v kontaktu s kapalnou fází. Hematit je stabilní v alkalickém prostředí, ale méně stabilní v kyselém prostředí. V této práci poprvé ukazueme pokrytí porézního Sn-dopovaného hematitu tenkými krycími vrstvami TiO2, deponovanými depozicí atomárních vrstev (ALD) a dopad těchto vrstev na chemickou stabilitu a stabilitu fotoproudů. Nominální tlouštky ALD TiO2 vrstev byly 0.5, 2 a 7.5 nm. Přítomnost TiO2 vrstev byla detekována pomocí rentgenové fotoelektronové spektroskopie, transmisní elektronové mikroskopie s vysokým rozlišením (HR-TEM) a skenovací TEM s energiově disperzním detektorem (EDX). HR-TEM analýzy odhalili, že TiO2 vrstavy byly rovnoměrné a zárověn amorfní. Jejich expozice nepokrytého hematitu v 1M kyselině sírové způsobila rozpouštění o rychlosti 0.23 nm/h, přičemž tato hodnota poklesla o polovinu při pokrytí TiO2 vrstvou (7.5 nm). Díky energetické nevyrovnanosti valenčních pásů obou polovodičů docházelo ke graduálnímu poklesu vygenerovaných fotoproudů s rostoucí tloušťkou krycí vrstvy. Následné žíhání deponovaných hematitů zvýšilo fotoproudy, které byly v případě nejtenčí krycí vrstvy (0.5 nm) dokonce vyšší než fotoproudy samotného hematitu
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