Equilibrium and dynamic moisture adsorption behaviour of bloodmeal based bioplastic

Bioplastics can be manufactured from protein or carbohydrate sources such as wheat gluten, corn, sun flower, keratin, casein, soy, gelatine and whey. A recently developed bioplastic is Novatein thermoplastic (NTP), which is produced from bloodmeal by adding water, urea, sodium sulphite, sodium dodecyl sulphate and tri-ethylene glycol (TEG), allowing it to be extruded and injection moulded. Bioplastics, compared to their petroleum counterparts, can readily adsorb or lose water, which then changes their physical properties such as tensile strength and glass transition temperature. NTP at different TEG and water contents was exposed to 20-85% relative humidity (RH) environments and change in mass recorded over 35 days to determine equilibrium and dynamic moisture adsorption behavior. Equilibrium behavior was modelled using modified Freundlich and Langmuir- Freundlich isotherms, and dynamic behavior modelled using Pilosof, Singh- ulshrestha, exponential, Langmuir-Freundlich and simple rate equations. Excellent fits were obtained for both isotherms and the last three rate equations gave best overall fits for dynamics. NTP adsorbed up to 28% by weight in water at 85% RH, reaching equilibrium within 20 days. Plastics with high TEG had a greater affinity for water but lower water adsorption rates, while dry plastic samples had a lower adsorption rate than wet samples. The two parameter Freundlich model and the exponential or simple rate model is recommended for modelling NTP equilibrium and dynamic water adsorption

Estonian total ozone climatology

International audienceThe climatological characteristics of total ozone over Estonia based on the Total Ozone Mapping Spectrometer (TOMS) data are discussed. The mean annual cycle during 1979?2000 for the site at 58.3° N and 26.5° E is compiled. The available ground-level data interpolated before TOMS, have been used for trend detection. During the last two decades, the quasi-biennial oscillation (QBO) corrected systematic decrease of total ozone from February?April was 3 ± 2.6% per decade. Before 1980, a spring decrease was not detectable. No decreasing trend was found in either the late autumn ozone minimum or in the summer total ozone. The QBO related signal in the spring total ozone has an amplitude of ± 20 DU and phase lag of 20 months. Between 1987?1992, the lagged covariance between the Singapore wind and the studied total ozone was weak. The spring (April?May) and summer (June?August) total ozone have the best correlation (coefficient 0.7) in the yearly cycle. The correlation between the May and August total ozone is higher than the one between the other summer months. Seasonal power spectra of the total ozone variance show preferred periods with an over 95% significance level. Since 1986, during the winter/spring, the contribution period of 32 days prevails instead of the earlier dominating 26 days. The spectral densities of the periods from 4 days to 2 weeks exhibit high interannual variability

Design Principles for Two-Dimensional Molecular Aggregates Using Kasha's Model: Tunable Photophysics in Near and Short-Wave Infrared

Technologies which utilize near-infrared (700 – 1000 nm) and short-wave infrared (1000 – 2000 nm) electromagnetic radiation have applications in deep-tissue imaging, telecommunications and satellite telemetry due to low scattering and decreased background signal in this spectral region. It is therefore necessary to develop materials that absorb light efficiently beyond 1000 nm. Transition dipole moment coupling (e.g. J-aggregation) allows for redshifted excitonic states and provides a pathway to highly absorptive electronic states in the infrared. We present aggregates of two cyanine dyes whose absorption peaks redshift dramatically upon aggregation in water from ~800 nm to 1000 nm and 1050 nm respectively with sheet-like morphologies and high molar absorptivities (e ~ 105 M-1cm-1). We use Frenkel exciton theory to extend Kasha’s model for J and H aggregation and describe the excitonic states of 2-dimensional aggregates whose slip is controlled by steric hindrance in the assembled structure. A consequence of the increased dimensionality is the phenomenon of an intermediate “I-aggregate”, one which redshifts yet displays spectral signatures of band-edge dark states akin to an H-aggregate. We distinguish between H-, I- and J-aggregates by showing the relative position of the bright (absorptive) state within the density of states using temperature dependent spectroscopy. I-aggregates hold potential for applications as charge injection moieties for semiconductors and donors for energy transfer in NIR and SWIR. Our results can be used to better design chromophores with predictable and tunable aggregation with new photophysical properties

Mismorphism: a Semiotic Model of Computer Security Circumvention (Extended Version)

In real world domains, from healthcare to power to finance, we deploy computer systems intended to streamline and improve the activities of human agents in the corresponding non-cyber worlds. However, talking to actual users (instead of just computer security experts) reveals endemic circumvention of the computer-embedded rules. Good-intentioned users, trying to get their jobs done, systematically work around security and other controls embedded in their IT systems. This paper reports on our work compiling a large corpus of such incidents and developing a model based on semiotic triads to examine security circumvention. This model suggests that mismorphisms---mappings that fail to preserve structure---lie at the heart of circumvention scenarios; differential perceptions and needs explain users\u27 actions. We support this claim with empirical data from the corpus

An Integrated XRF/XRD Instrument for Mars Exobiology and Geology Experiments

By employing an integrated x-ray instrument on a future Mars mission, data obtained will greatly augment those returned by Viking; details characterizing the past and present environment on Mars and those relevant to the possibility of the origin and evolution of life will be acquired. A combined x-ray fluorescence/x-ray diffraction (XRF/XRD) instrument was breadboarded and demonstrated to accommodate important exobiology and geology experiment objectives outlined for MESUR and future Mars missions. Among others, primary objectives for the exploration of Mars include the intense study of local areas on Mars to establish the chemical, mineralogical, and petrological character of different components of the surface material; to determine the distribution, abundance, and sources and sinks of volatile materials, including an assessment of the biologic potential, now and during past epoches; and to establish the global chemical and physical characteristics of the Martian surface. The XRF/XRD breadboard instrument identifies and quantifies soil surface elemental, mineralogical, and petrological characteristics and acquires data necessary to address questions on volatile abundance and distribution. Additionally, the breadboard is able to characterize the biogenic element constituents of soil samples providing information on the biologic potential of the Mars environment. Preliminary breadboard experiments confirmed the fundamental instrument design approach and measurement performance

Flexibiliteit èn zekerheid in waterbeheer, het kan: interactieve uitvoering

In complexe, gebiedsgerichte projecten staat een projectleider vaak voor een dilemma: moeten we keuzes snel vastleggen of juist mogelijkheden openhouden? Met openhouden creëer je flexibiliteit. Het geeft ruimte om in te blijven spelen op onverwachte ontwikkelingen in het planproces. Met snel vastleggen creëer je zekerheid. Het geeft je planproces richting en duidelijkheid. Ondergetekenden betogen dat de oplossing van dit dilemma ligt in het combineren van flexibiliteit met zekerheid. Aan de hand van een concreet waterschapsproject laten we zien dat dit combineren mogelijk is. We bieden bovendien ideeën die andere projectleiders kunnen helpen om ook in hun projecten flexibiliteit en zekerheid te combineren

Algorithmic statistics: forty years later

Algorithmic statistics has two different (and almost orthogonal) motivations. From the philosophical point of view, it tries to formalize how the statistics works and why some statistical models are better than others. After this notion of a "good model" is introduced, a natural question arises: it is possible that for some piece of data there is no good model? If yes, how often these bad ("non-stochastic") data appear "in real life"? Another, more technical motivation comes from algorithmic information theory. In this theory a notion of complexity of a finite object (=amount of information in this object) is introduced; it assigns to every object some number, called its algorithmic complexity (or Kolmogorov complexity). Algorithmic statistic provides a more fine-grained classification: for each finite object some curve is defined that characterizes its behavior. It turns out that several different definitions give (approximately) the same curve. In this survey we try to provide an exposition of the main results in the field (including full proofs for the most important ones), as well as some historical comments. We assume that the reader is familiar with the main notions of algorithmic information (Kolmogorov complexity) theory.Comment: Missing proofs adde

The inverse Laplace transform as the ultimate tool for transverse mass spectra

New high statistics data from the second generation of ultrarelativistic heavy-ion experiments open up new possibilities in terms of data analysis. To fully utilize the potential we propose to analyze the $m_\perp$-spectra of hadrons using the inverse Laplace transform. The problems with its inherent ill-definedness can be overcome and several applications in other fields like biology, chemistry or optics have already shown its feasability. Moreover, the method also promises to deliver upper bounds on the total information content of the spectra, which is of big importance for all other means of analysis. Here we compute several Laplace inversions from different thermal scenarios, both analytically and numerically, to test the efficiency of the method. Especially the case of a two component structure, related to a possible first order phase transition to a quark gluon plasma, is closer investigated and it is shown that at least a signal to noise ratio of $10^4$ is necessary to resolve two individual components.Comment: 13 pages (PostScript, including figures), BNL-NTHES