Determination of nutrient values of the bivalve Anodonta cygnea in Selkeh area of the Anzali Lagoon during autumn and spring

Anzali Lagoon is one of the most important aquatic ecosystems of Iran which was registered as a Ramsar Convention site in 1999. This valuable ecosystem is located in the south west shores of the Caspian Sea, in Guilan Province. We randomly collected 30 and 20 samples of the bivalve Anodonta cygnea in autumn 2004 and spring 2005 respectively. The Selkeh area was chosen for the sampling because of its availability during autumn. The area receives water from the southern part of the lagoon basin. Nutrient content of the soft tissue of the bivalve was measured. Live sampled bivalves were transferred to laboratory and their length, width, height; total body weight and wet weight of the internal soft part were measured. Moisture, ash, protein, T.V.N, lipid and amino acid contents in soft tissue were also determined. Moisture content in spring and autumn samples were 84.84% and 83.6%, respectively. Ash content in autumn samples was higher than spring samples, being 4% and 2.32%, respectively. Assessment showed protein content in the autumn samples to be 12% while in spring samples this was 10.5%. T.V.N content in autumn and spring samples were 0.031 and 0.003% respectively. Measurements showed that autumn bivalves had 4% lipid content whereas this value in spring samples was 3%. We found Sixtheen amino acids, including seven essential ones in the samples

Protein and lipid changes of FPC produced from Caspian Sea kilkas in VP and MAP during storage at different temperatures

Fish Protein Concentrate (FPC) is a healthy, sustainable and high nutritive product that produced from fish and protein and other nutrients are more concentrated than in the fresh fish. The aim of this research is to study the sustainability of FPC produced from Kilka (combination of three Caspian Sea Kilka species, Clupeonella engrauliformis, C. grimmi and C. cultriventris which were not identified and processed separately) in VP (Vacuum Packaging) and MAP (Modified Atmosphere Packaging) at different temperatures during six months of storage. According to result of chemical analysis performed, protein content was evaluated 91.2%, lipid 0.5%, ash 3.6%, moisture 2.3%, TVN 10 mg/100g and peroxide 5 meq/kg in the produced FPC before packing. Amino acids and fatty acids were also determined. Lipid amount in FPC after 6 months at 35°C in VP changed from 0.50 to 0.45 and in MAP (combined of 60% CO2, 30% N2 and 10% O2), decreased from 0.50 to 0.36. It was also detected that increase in temperature leads to more decrease in lipid content but it was not significant (P>0.05). Protein content of FPC has changed from 91.2% to 73.6% during six months at 35°C in VP and 69.4% in MAP. But at 5°C, protein contents were changed from 91.2% to 88.4% and 81.2% in VP and MAP, respectively; these changes were significant (P<0.05) but the decrease in MAP was again more than VP

Design and Manufacture of Surface Topography with Additive Manufacturing: Properties and Applications

The first study investigates the impact of surface texture parameters of natural surface specimens on the attachment of algae communities. The primary objective of this effort is to show feasibility in the approach of reverse engineering natural surfaces (developing surface features that are biomimetically inspired) to enhance the attachment and species selectivity of benthic algae used in water pollution recovery systems. A secondary objective seeks to elucidate which surface parameters appear to explain the attachment behavior of a selected species. Finally, a method of reverse engineering natural surfaces is proposed in this study that can be implemented in other real-world applications. This work seeks to reveal the surface topography parameters that were significant for algal attachment by manipulating surface topographies using additive manufacturing. In this study, a method for capturing and reversing natural substrata has been developed and proven feasible. Natural rocks and surfaces with attached biofilms were retrieved from streams, scanned with optical profilometry, and the surface characteristics were analyzed. The results show that certain texture parameters (e.g., Smr, Sa, and Sv) show promise in predicting surface colonization by algae. The Pearson distribution was utilized to generate pseudo-randomized surfaces with surface characteristics. A material jetting process was used to additively manufacture the surfaces followed by optical profilometry to validate the resultant topography. The results validated that the set of Sa, Sv, and Smr significantly predict the surface adhesion of benthic algal species. The second study aims to demonstrate the effects of geometric parameters such as shape, length, height, and pitch size of custom-3-D printed microtextured surfaces on receding and advancing water contact angle. This study reveals that the wetting behavior is highly dependent on the texture design. In addition, the geometrical parameters of the design such as shape, length, height, and pitch size significantly affect the contact angle. Among the geometrical parameters, the shape parameter had the greatest effect on contact angle, and the results indicated that groove design is strongly more hydrophobic than circular protrusion textures. In the third study, three different issues regarding surface topography that are induced in 3-D printed surfaces are studied. In this study, three objectives were pursued: a) analyzing the surface finish and dimensional accuracy of material jetting processes in different designs and sizes, b) analyzing the effects of build orientation and surface slope on the fidelity of different surface texture designs, and c) analyzing the effects of tile thickness and build orientation on surface distortion and warpage. The results show that protrusion features have fewer dimensional errors than debossed features, especially for sizes smaller than 500 μm. In sizes smaller than 500 μm, the designs of features are indistinguishable and all printed features appear spherical. Slipping of partially cured (solidified) materials deposited right at the edge of features results in rounded shape edges and dimensional errors in fabricated designs. This work indicated that surface slope creates stair-stepping, which affects different aspects of surface characteristics. The height and volumetric functional parameters are significant among others and show a better surface finish for the 0° surface slope compared to the 45° surface slope. This study showed that if the build tray is orientable through the printing process, the build tray can be tilted to variable degrees to increase the dimensional accuracy and create sharper edges for some designs such as polygons (not curved features) and features with recess designs. Increased surface slope also brings disadvantages such as a stair-stepping effect, a rough surface, asymmetry, and remains of the traces of moved material along the slope. Minimizing the dimensional distortion in material jetting processes requires consideration of both the part design and process conditions. The type of distortion generated by a high aspect ratio specimen is dependent on the part thickness of the specimen, while the build orientation becomes a significant process parameter only when in very thin sections. The development of design guidelines should incorporate the knowledge that most geometries will experience distortion along the longest axis and that increasing wall thicknesses will help minimize potential deformations. Also, whenever thin part sections (~1 mm) are fabricated, the YX build orientation appears to decrease the amplitude of the deformation wave, as expressed by the height of the highest peak

Thermodynamic and Numerical Analysis of Tangentially Fired Boiler for Increasing Efficiency and Reducing Environmental Pollution

The evaluation of heat transfer and fluid mechanics mechanisms to increase the thermal efficiency and combustion quality in heavy industries, such as power plants, are important and significant issues in the field of engineering sciences, which can lead to significant advances. In this regard, the present paper has been developed with thermodynamic and numerical simulations of the MONTAZER GHAEM Power Plant boiler to study the increase in efficiency and reduce environmental pollution. Also in this research, the results of practical tests have been used to verify the simulations. The thermodynamic simulation results show that the required fuel consumption of the burners in current operating conditions is not 9.1 kg/s, but it is 8.1 kg/s. The low efficiency of the set, which leads to the injection of more than the required amount of fuel to the boiler, cause the non-corresponding power generation for injected fuel, which results in the reduction of the plant thermal efficiency from 36.4% to 33.9%. The results of computational fluid dynamics show that the lightness of natural gas combustion products and, the no-flow accumulation in the lower parts of the furnace, reduce the produced steam, which results in power loss at the exit. Numerical results also show that the highest rate of NOX production occurs near the burners due to the high flame temperature and high oxygen mass fraction and consequently, the non-uniform distribution of heat in the furnace

Study on the sustainability of FPC produced from Kilka (Clupeonella engrauliformis, C. grimmi and C. cultriventris) in two vacuum packaging and modified atmosphere packaging at different environmental factors

Fish protein concentrate (FPC) is a healthy, sustainable and high nutritive product which sanitized produced from fishes in which, protein and other nutrients are more concentrated than in fresh fishes. The aim of this research is to study on the sustainability of FPC produced from Kilka (Clupeonella engrauliformis , C. grimmi and C. cultriventris) in two Vaccum Packaging and Modified Atmosphere Packaging at different environmental factors during six months. In our study the analysis of FPC protein showed 91.2%, lipid: 0.5%, ash: 3.6%, moisture: 2.3%, Total Volatile Nitrogen: 10 ml/100gr and peroxide: 5meq/kg. Amino acids and fatty acids were also determined. Bacteria and Fungi were lower than 1000 colony. Samples are kept in different condition of temperature (5, 20 and 35 degree centigrade), humidity (25, 40 and 90 percent) and light and dark environment in six month. Lipid rate in FPC after 6 months in VP and MAP (60% C02, 30 % N2 and 10% O2), packages was decreased but was not significant (P>0.05). It was also detected that increase temperature lead to more decrease in lipid content. Protein rate of FPC was decreased from 91.2% to 73.6% during six months at 35°C in VP Package and from 91.2% to 69.4% in MAP package. These changes were significant (P<0.05). TVN and PV rate in FPC after 6 months in VP and MAP packages was increased but was significant (P<0.05). Amino acids and fatty acids were also determined. But more changes in MAP packages was detected

Adaptation of Line Operations Safety Audit (LOSA) to Dispatch Operations (DOSA)

Purpose: Dispatch Operations Safety Audit (DOSA) is a proactive and predictive method in safety management system that detects the capabilities and pitfalls of dispatcher performance. In this study, Dispatch-Line Operations Safety Audit is carried out in an airline and results are analyzed and discussed. Design/methodology: The method of DOSA implementation for flight operations officers is similar to LOSA for flight crew. Findings: Results show that DOSA has an important effect on Threat and Error Management (TEM) in the Operations Control Center (OCC). Originality/value: Potential applications of this research include the better threat and error management in OCC with the implementation of DOSA as well as identification of threats and errors types for FOOs in OCC. Also, distribution of threats and errors in different phases of dispatch shift is discussed, therefore syllabuses of training courses can be provided with respect to threat and error types for flight operations officers.Peer Reviewe

Phase Identification and Size Evaluation of Mechanically Alloyed Cu-Mg-Ni Powders

Ternary mixture of Cu, Mg, and Ni with the nominal composition of nanocrystalline Cu50Mg25Ni25 (in at.%) was milled for 25 hours. Analysis of an X‐ray diffraction pattern (XRD) and transmission electron microscopy (TEM) was used to characterize the chemical phases and microstructure of the final product, which is shown to consist of ternary alloy of Cu‐Mg‐Ni with FCC structure along with small amounts of FCC MgO and Mg0.85Cu0.15. The good agreement between the size values obtained by XRD and TEM is attributed to the formation of defect‐free grains with no substructure during ball milling. Dynamic recrystallization may be a possible mechanism for the emergence of such small grains (<20 nm). The particle size distribution and morphological changes of Cu–Mg–Ni powders were also analyzed by scanning electron microscopy (SEM). According to the SEM results, the particle size of the powders decreased with increasing milling time. Lattice parameter of the Cu‐Mg‐Ni ternary FCC alloy formed during mechanical alloying increased with increase in milling time from 3.61 to 3.65 Å after 20 hours milling

A new operational characteristic for diagnosing the healthy and faulty currents of power transformers

The inrush currents of transformers are among the main causes which compromise the performance of the protection relays in practice. Therefore, the discrimination between the inrush currents and faults is very important. A new technique is proposed in this paper to distinguish the internal fault of transformers and other normal transient conditions (such as inrush current). Accordingly, a new operational characteristic is defined for feature extraction and classification of the instantaneous current behavior based on the modal transform. The internal fault current is accurately and rapidly discriminated from the other transient current conditions (such as load switching, and inrush currents) by tracking the differential current curve. Furthermore, the real transformer is simulated to validate the proposed method by the PSCAD-EMTDC and MATLAB software. Furthermore, the real data of the actual fault in the transformer of the Iranian power network is studied. The simulation results show the stability, reliability, simplicity, and high speed of the proposed method in the discrimination of the fault current from inrush current. The method is compared with its other intelligent counterparts and the results confirm a clear improvement.</p

Tin-doped Indium Oxide (ITO) Nanocrystal Superlattices (Surface Chemistry, Charge Transport, and Sensing Applications)

This cumulative dissertation is based on three publications. It investigates the surface chemistry of nanocrystals (NC), charge transport in NC superlattices, and energy level alignment at organic/inorganic interfaces. The materials of choice are tin-doped indium oxide (ITO) NCs as well as the organic semiconductors metal-4,4',4″,4‴-tetraaminophthalocyanine (M4APc) and perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA). A wet chemical approach is used to synthesize the NCs and to control the doping concentration. Macroscopic superlattices of ITO NCs are prepared by a Langmuir-type self-assembly at the air/liquid interface followed by simultaneous ligand exchange with Cu4APc. X-ray photoelectron spectroscopy (XPS), grazing-incidence small-angle X-ray scattering (GISAXS), and ultraviolet-visible-near-infrared (UV-vis-NIR) spectroscopy are used to track the chemical changes on the nanocrystals’ surface before and after ligand exchange and develop a detailed picture of the various components which dominate the surface chemistry of this material. It is demonstrated that the semiconductor molecules largely replace the native surfactant from the ITO NC surface and act as cross-linkers between neighboring particles. Transport measurements reveal a significant increase in electrical conductance, suggesting that Cu4APc provides efficient electronic coupling for neighboring ITO NCs. This material provides the opportunity to study charge and spin transport through phthalocyanine monolayers. Next, the choice of the metal center of M4APc is expanded to Cu, Co, Fe, Ni, and Zn. These ligands are incorporated into the array of ITO NCs, and the charge carrier transport and resistance-mediated vapor sensing are investigated. Varying the metal center provides the opportunity to systematically study the sole effect of the tunneling barrier height on charge transport through the nanocrystal array, while all other parameters are kept constant. Transport measurements, focusing on the effect of the metal center of the ligand, reveal a ligand-dependent increase in electrical conductance. The resulting I–V characteristics as well as the temperature dependence of the zero-voltage conductance indicates that at low temperatures, transport across the arrays occurs via a sequence of inelastic cotunneling events. At higher temperatures, a crossover to 3D Mott variable range hopping (VRH) mechanism is observed. The vapor sensitivity of chemiresistors made from ITO NCs arrays is investigated by dosing the sensors with four different analytes and concentrations as low as 100 ppm. By testing different classes of analytes, different selectivities of the materials is also registered, depending on whether the analytes behave more vapor- or more gas-like. Finally, a wide range of substrates (unreactive, reactive or passivated metals and polymers) with different work functions and coupling interactions are used to investigate the electronic structure at the substrate/PTCDA interface by XPS, ultraviolet photoelectron spectroscopy (UPS), and electrostatic calculations. For thick layers of PTCDA, nearly unchanged electron and hole injection barriers on all substrates are observed without any dependence on the type of substrate. For few monolayers of PTCDA, this seemingly universal Fermi level pinning is perturbed depending on the nature of the substrate and the thickness. This behavior is explained with a large induced density of interface states. Using standard electrostatic calculation models as well as introducing extensions to previously reported approaches, the origin of universal Fermi level pinning and its underlying mechanism is investigated. The simulation results demonstrate how the shape of the DOS near the interface has long-range influence on key parameters (e.g. the barrier to charge injection) of the entire organic film.Die vorliegende kumulative Dissertation basiert auf drei Publikationen. Sie behandelt die Oberflächenchemie von Nanokristallen (NC), Ladungstransport in NC Übergittern und die Energieniveauausrichtung an organisch/anorganischen Grenzflächen. Bei den untersuchten Materialien handelt es sich um Indiumzinnoxid (ITO) NCs und organische Halbleiter der Metall-4,4',4″,4‴-tetraaminophthalocyanine (M4APc) und Perylen-3,4,9,10-tetracarbonsäuredianhydrid (PTCDA). Eine nasschemische Herangehensweise wird für die Synthese der NCs und die Kontrolle ihrer Dotierungskonzentration gewählt. Durch eine Langmuir-artige selbst-Assemblierung an der Flüssig-Gas-Grenzfläche mit parallel ablaufendem Ligandenaustausch mit Cu4APc werden makroskopische Übergitter aus ITO-NCs hergestellt. Röntgenphotoelektronenspektroskopie (XPS), Röntgenkleinwinkelstreuung unter streifendem Einfall (GISAXS) und UV/Vis/NIR-Spektroskopie werden verwendet, um die chemischen Veränderungen der Oberfläche der Nanokristalle vor und nach Ligandenaustausch zu verfolgen und um ein detailliertes Bild der unterschiedlichen Komponenten zu erhalten, die die Oberflächenchemie dieses Materials dominieren. Es wird gezeigt, dass die halbleitenden Moleküle die ursprünglichen Liganden von der ITO Oberfläche größtenteils ersetzen und als Vernetzer zwischen benachbarten Partikeln fungieren. Transportmessungen weisen eine signifikante Erhöhung der elektrischen Leitfähigkeit auf und legen damit nahe, dass Cu4APc zu einer effizienten elektronischen Kopplung benachbarter ITO NCs führt. Dieses Material bietet die Möglichkeit, Ladungs- und Spintransport durch Phthalocyaninmonolagen zu untersuchen. Im nächsten Schritt wird die Wahl des Metallzentrums von M4APc auf Cu, Co, Fe, Ni und Zn ausgedehnt. Diese Liganden sind in die Anordnung der ITO NCs integriert, und es werden Ladungsträgertransport sowie die Widerstands-abhängige Detektion von Dampf dieser hybriden Materialien untersucht. Die Variation des Metallzentrums ermöglicht es, systematisch den alleinigen Effekt der Höhe der Tunnelbarriere auf den Ladungstransport durch die Nanokristallanordnung zu untersuchen, während alle anderen Parameter konstant gehalten werden. Transportmessungen, die sich auf den Effekt des Metallzentrums des Liganden fokussieren, zeigen eine Liganden-abhängige Erhöhung der elektrischen Leitfähigkeit. Die resultierende I-V-Kennlinie und die Temperaturabhängigkeit Leitfähigkeit im Niedrigfeld deuten darauf hin, dass bei niedrigen Temperaturen Ladungstransport durch das Gitter durch eine Sequenz von inelastischen Ko-Tunnelereignissen erfolgt. Bei höheren Temperaturen wird ein Übergang zum 3D Mott-VRH Mechanismus beobachtet. Die Empfindlichkeit der Chemosensoren, die aus ITO NCs Anordnungen bestehen, wird gegenüber Dämpfen untersucht, indem die Sensoren mit vier unterschiedlichen Analyten und Konzentrationen – bis hinab zu 100 ppm – beladen werden. Es zeigt sich durch Untersuchung verschiedener Analytenarten, dass das Material unterschiedliche Selektivitäten aufweist, die davon abhängen, ob sich die Analyten eher dampf- oder gasartig verhalten. Zuletzt wird eine Vielzahl an Substraten (inerte, reaktive oder passivierte Metalle und Polymere) mit unterschiedlichen Austrittsarbeiten und Kopplungswechselwirkungen eingesetzt, um die elektronische Struktur der Substrat/PTCDA Grenzfläche mittels XPS, Ultraviolettphotoelektronenspektroskopie (UPS) und elektrostatischen Berechnungen zu untersuchen. Bei dicken PTCDA-Schichten werden, ohne eine Abhängigkeit von der Art des Substrates ausmachen zu können, nahezu unveränderte Elektronen- und Lochinjektionsbarrieren auf allen Substraten beobachtet. Für wenige Monolagen an PTCDA wird diese scheinbare universelle Fixierung des Ferminiveaus abhängig von der Natur des Substrats und der Filmdicke gestört. Dieses Verhalten wird mit einer großen induzierten Grenzflächenzustandsdichte erklärt. Durch Verwendung von standardmäßigen elektrostatischen Kalkulationsmodellen und durch Einführung von Erweiterungen zu bereits berichteten Herangehensweisen wird der Ursprung der universellen Fixierung des Ferminiveaus und dessen zugrundeliegender Mechanismus untersucht. Die Simulationsergebnisse demonstrieren, wie die Form der Zustandsdichte in der Nähe der Oberfläche einen Einfluss langer Reichweite auf Schlüsselparameter (z. Bsp. die Barriere der Ladungsträgerinjektion) des gesamten organischen Films hat