30 research outputs found
Efficiency of immunomodulating therapy in acute obstructive bronchitis in children
No full textA corrective method for the treatment of acute obstructive bronchitis is proposed, including T-activin in the complex therapy of children with acute obstructive bronchitis. In order to correct the immunological parameters, patients with ARD were prescribed T-activin subcutaneously at the rate of 2 μg / kg of body weight daily for 5 days and the sixth injection a week after injections. Clinically, all children who received T-activin showed positive dynamics with an increase in the effectiveness of treatment, which contributed to the normalization of indicators of the immune status of patients and prevented the development of relapses of the diseas
Efficiency of application of Phyto and Vitaminotherapy in the complex treatment of endemic goiter
No full textA corrective method for the treatment of endemic goiter has been proposed, including anise powder and elecampane root, 1 teaspoon 3 times a day for 1 month, along with a complex of B vitamins (B1, B2, B6), nicotinic (vitamin PP) and ascorbic acid (vitamin C) in the form of a rosehip tincture for 3-5 days, depending on the severity of the disease. It has been shown that the corrective method of therapy for endemic goiter leads to restoration of intestinal microbiocenosis, elimination of iodine and vitamin deficiencies, disappearance of clinical symptoms of the disease and normalization of the level of thyroid hormones
Literature review Quasi-static and Dynamic pile load tests: Primarily report on non-static pile load tests
No full textPile testing, which plays an importance role in the field of deep foundation design, is performed by static and non-static methods to provide information about the following issues: (Poulos, 1998) - The ultimate capacity of a single pile. - The load-displacement behavior of a pile. - The performance of a pile during the test conditions. - The integrity of a pile (pile integrity test). For the purposes of verification the design axial capacity and the static load – settlement behavior of piles, the static pile load test has long been considered as the most reliable method but because of its high cost and time consuming, non – static pile load tests are looked as efficient substitutions. The two non – static testing methods, i.e. dynamic and quasi – static pile load test are objects of this report. The non – static pile load tests are performed by means of exerting an impact force on the pile head while measuring and recording the responses of the pile, from which the test results are determined. Duration of the impact force (T), longitudinal wave velocity of tested pile (c) and pile length (L) are used as key factors to classify the testing methods
Rapid load testing of piles in sand: Effect of loading rate and excess pore pressure
No full textCivil Engineering and Geoscience
MACROKINETIC AND KINETIC REGULARITIES OF CYANIDATION REACTION OF HIGHER ALIPHATIC ALCOHOLS
No full text<p>It was studied the macromolecular and kinetic study of high molecular alcohols of the reaction of cyanide with ammonia on the CHM-1 catayst. In order of to study the macromolecular dependence of nitrile production yield on the rate of gas stream and the diameter of the catalyst. The partial pressures of reactants and products also found to affect to the rate of the reaction.</p>
Morphology of the Eastern Scheldt ebb tidal delta
No full textThe Eastern Scheldt tidal basin and its ebb tidal delta have changed drastically in the recent centuries under the influence of natural processes and human interventions. A Storm Surge Barrier, one of constructions within framework of Delta Project in the Eastern Scheldt, is considered as the largest impact to changes in hydrodynamics and morphology of the ebb tidal delta. The barrier was built in 1987 to maintain the tide and to protect the area from flooding. The barrier closes under severe storm surge conditions and remains open during normal conditions to preserve the tide-dominated character of the ecosystem. However, this storm surge barrier caused a reduction of tidal volume and tidal current in the Eastern Scheldt. Since 1987, there has been a remarkable reduction of the tidal prism by 30%, of the average tidal range by 12% and of the average tidal current velocities by 33%. As a result, sediment export from the basin towards its ebb tidal delta has ceased. This led and still to changes in morphology of the ebb tidal delta. In order to adapt to changes in tidal volume, the tidal channels become sinks of sediment and this sediment has been and still is taken from the tidal shoals nearby. Sediment volume of these shoals therefore has decreased drastically. The deposition in channels and erosion on the shoals caused a number of negative effects to ecology, safety, navigation, recreations and fishery in the Eastern Scheldt. To analyse the morphological developments of the ebb tidal delta before, during and after the implementation of the Storm Surge Barrier in the Eastern Scheldt, bathymetry maps which present the changes in deposition and erosion parts in the ebb tidal delta in every four years (from 1960 to 2004) were used. In summary, the morphology of the Eastern Scheldt ebb tidal delta experienced enormous changes due to the Delta Project. These changes comprise shoaling and reorientation of channels- from updrift to downdrift (northward) migration of channels, landward migration of shoals, development and diminishing of ebb and flood chutes and development of scour holes near the entrance of the storm surge barrier. As a result, it would take a long time (centuries) to establish a new dynamic equilibrium between hydraulic conditions and geomorphology in the Eastern Scheldt inlet.CoMEM - Coastal and Marine Engineering and ManagementHydraulic EngineeringCivil Engineering and Geoscience
Afzinktunnel 't Groene Hart: Een andere aanpak
No full textBegin 1997 keurde het parlement de Planologische Kernbeslissing HSL-Zuid goed, waarin een 7 km-Iange boortunnel onder het Groene Hart is opgenomen. Het Atelier HSL-Zuid, dat werd opgericht om te kijken waar meer innovatie mogelijk was in het PKB, stelde in "Overstappen" voor om de tunnel te bouwen volgens de afzinkmethode in plaats van de boormethode. Voor het transporteren en afzinken van de tunnelelementen wordt de "Nieuwe Hoogeveensche Vaart" aangelegd die later wordt gehandhaafd. Zo kan veel geld worden bespaard en daarnaast een meerwaarde aan het Groene Hart worden gegeven door de ecologische en recreatieve functie die de vaart gaat vervullen. Deze studie is erop gericht dit idee nader uit te werken voor een 10 km-lange variant, waarbij de kostenoptimalisatie centraal staat. Teneinde de kosten laag te houden, dient de transportvaart enkel met dijken en oevers ondertalud te worden aangebracht zonder technische oplossingen als damwanden, L-muren etc. Op deze manier kan binnen de 75 m brede werkzone een vaartdiepte van 3,6 m worden gerealiseerd. De diepgang van de tunnelelementen tijdens transport moet derhalve gering zijn. Voor het afzinken zijn damwanden nodig, om te kunnen ontgraven tot het gewenste niveau. Door deze steeds te trekken en opnieuw te gebruiken worden de kosten beperkt. De tunnel wordt uitgevoerd als een dubbelsporige buis, ondersteund door kolommen. Van de vele mogelijkheden om de diepgang tijdens transport te beperken (verlagen betonhoeveelheid,verlagen volumiek gewicht beton, verhogen volumiek gewicht water, vergroten ondergedompelde breedte) is de eerstgenoemde het aantrekkelijkst, omdat die geen extra kosten, maar zelfs een besparing met zich meebrengt. De met de ondiepe ligging gepaard gaande kleine belastingen maken het mogelijk zeer licht te dimensioneren. Het resultaat is behalve een kleine diepgang minder materiaalverbruik. Vanwege de grote tunnellengte is het lonend de tunnelelementen industrieel te vervaardigen. De voordelen zijn ondermeer een kortere bouwtijd, effectiever materieel- en materiaalgebruik en minder weerinvloeden. Hierdoor kan tegen relatief lage kosten een hoge betonsterkte (B65) worden bereikt, hetgeen de constructie nog lichter maakt. Van de middelen om de tunnel te beschermen tegen opdrijven (ballastbeton, zand, trekpalen, groutankers) is de laatst genoemde het goedkoopst gebleken, zelfs 50% goedkoper dan de gangbare oplossingen met beton. De geschetste oplossing is 33% goedkoper dan de boortunnel en 40% goedkoper dan alle te vervangen werken. Bijkomende voordelen zijn de verlenging van de tunnel met 3 km en een vaart voor recreatie die ook ecologisch belangrijk zal zijn. De bouwtijd (3 jaar) en het grondgebruik zijn goed inpasbaar in het Ontwerp Trace Besluit HSL-Zuid 1997.Hydraulic EngineeringCivil Engineering and Geoscience
Non-deterministic networked infrastructure design of multiple sources and multiple sinks
No full textNetworked infrastructures such as gas and water pipelines, roads, railroads or power grids provide essential utilities and services to society. Common characteristics of such infrastructures include high capital costs, generally long lifetimes and irreversibility once the construction of such networks have finished. In the design of these networks, the planners face a multitude of challenges ranging from traditional factors such as technical complexities, space-constrained areas to emerging factors such as complex multi-actor contexts and climate change. A chronic challenge is a multi-actor context in which supply capacities from the supplier side, demand capacities from the consumer side and information about the actual commitment of the network participants, who are about to be connected to the network, can remain uncertain for a long time. The uncertainty is especially high when the network involves multiple suppliers and multiple consumers. While deterministic network design ignores these uncertainties, non-deterministic network design takes them into consideration. The goal of this research is to develop an approach of designing a multiple source (supplier) - multiple sink (consumer) network layout that minimizes the initial investment costs while remaining flexible in its response to future changes of network participants. To this end, firstly an agent-based deterministic modeling method of Ant Colony Optimization was developed, which proved to be feasible in finding cost-minimized network layouts of multiple sources and multiple sinks. Next, the method was extended to a non-deterministic method by embedding flexibility options in order to deal with the uncertainty on network participants. The modeling methods of Ant Colony Optimization were found to be intuitive, extensible and customizable. Based on the modeling outputs, the final design approach can be a supportive decision-making tool in the network planning stage. Future work needs to incorporate more practical criteria required by decision makers into the modeling to bridge the gap between scientific knowledge and decision making process in reality.Energy and IndustryEngineering Systems and ServicesTechnology, Policy and Managemen
Integrated Validation Plant: Modelling and optimisation of the biological treatment process
No full textThe wastewater infrastructure in Singapore is undergoing a major revamp, which includes the construction of a new water reclamation plant (WRP) in Tuas. This plant aims to maximise the energy recovered from wastewater, with the ultimate aim of achieving energy self-sufficiency. The Integrated Validation Plant (IVP) is a 1000 m3/day pilot plant equipped with an AB configuration. The A-stage biosorption process increases the amount of COD recovered in the primary sludge to increase biogas production, whereas the B-stage membrane bioreactor (MBR) treats the wastewater using activated sludge. The effluent then undergoes reverse osmosis (RO) to produce potable water. This report investigates the biological treatment process in the IVP and aims to answer the following question: Given that most WRP in Singapore uses the Modified Ludzack-Ettinger configuration (MLE; also known as the pre-denitrification configuration) for the B-stage, will a change in configuration reduce net energy consumption while achieving good effluent quality? The research is divided into three main parts with the following objectives: 1. To create and calibrate a Biowin model to simulate the biological treatment process in the IVP 2. To optimise the MBR B-stage by finding the configuration and operating conditions that requires the least influent COD to achieve acceptable effluent quality (in terms of COD, nitrogen and phosphorus), and to determine the appropriate changes in the A-stage (if any) that is required to achieve this effluent quality 3. To explore issues facing the IVP and future developments of wastewater treatment in Singapore – effect of an unaerated deoxygenation tank, feasibility of mainstream Anammox, and modification of the treatment process to reduce chemical dosage in the downstream RO process The Biowin model for the MBR was first calibrated using jar tests and oxygen uptake tests, then validated with profile studies that are being carried out in the MBR regularly. It was found that Biowin is able to model the biological treatment process relatively well, with the major discrepancy being that Biowin is not able to model ammonia adsorption onto activated sludge in the anoxic zone. With the calibrated model, various configurations and operating conditions were simulated to optimise the MBR. It was found that the optimal configuration is the Anoxic-Oxic-Anoxic-Oxic (AOAO) configuration with a step feed of 50% of the influent entering the first anoxic zone and 50% entering the second anoxic zone. The return activated sludge (RAS) flow should be 73% of the influent flow and the DO in the aerated tanks should be maintained at 1 mg/l. As the biosorption tank at the IVP is not functioning well, data was obtained from another biosorption pilot plant in Singapore to calibrate the A-stage. Using this calibrated biosorption model, the optimal MBR configuration, and the typical raw influent characteristics for the IVP, it was determined that a functioning biosorption stage will result in insufficient COD entering the MBR for sufficient phosphorus removal. To achieve the required effluent quality, the best option during steady state operations would be to reduce the sludge retention time (SRT) of the biosorption process from 0.5 days to 0.32 days by increasing sludge wastage as this leads to the highest overall COD recovery. On the other hand, the best method to cope with sudden increases in the nitrogen and phosphorus load in the raw influent would be to partially bypass the biosorption tank and divert some of the raw influent to the primary clarifier as this option results in the fastest response in the effluent quality. As the membrane tanks in the MBR are aerated to scour the membranes and minimise fouling, the mixed liquor in the tanks have a high concentration of dissolved oxygen (DO). A small deoxygenation tank is installed after the membrane tanks to allow DO to deplete before the mixed liquor is recycled back to the anoxic zone at the start of the MBR. However, the deoxygenation tank is not functioning well due to the presence of a cascade overflow from the membrane tanks. Simulations show that the presence of residual DO in the recycle stream leads to a large deterioration the biological phosphorus removal performance of the MBR, mainly due to reduced COD availability for the polyphosphate-accumulating organisms (PAOs). Modifications to reduce the impact of the cascade include the installation of baffle walls, slopes, or overflow pipes. One of the technologies for B-stage that can allow even higher COD recovery is mainstream Anammox for nitrogen removal, which consumes less COD than conventional nitrogen-removal processes. As it works best at temperatures of about 30oC, it may be suitable for implementation in Singapore where the average wastewater temperature is about 31oC. Biowin simulations revealed that mainstream Anammox can occur under the local conditions, with CANON and DEMON configurations being more suitable than the SHARON-Anammox configuration. However, a very high solids removal efficiency in the primary clarifier is required to remove sufficient COD in the A-stage for Anammox to develop in the B-stage. Further studies would be required to determine if this is achievable under local conditions. Lastly, the MBR effluent is sent to a RO process to be reclaimed as potable water. Ammonia and sodium hypochlorite is first added to produce chloramine to prevent biofouling and provide the necessary residual disinfection. it was found that the ammonia concentration in the MBR effluent can be increased sufficiently to remove the need for ammonia dosage. However, the reduced nitrification also resulted in a higher nitrite concentration in the effluent, increasing the amount of sodium hypochlorite needed to produce the required chloramine as sodium hypochlorite also oxidises nitrite into nitrate. In addition, the dosage of anti-scalants can be reduced with better phosphorus removal as the lower effluent phosphorus leads to less scaling potential in the RO process by calcium phosphate.Sanitary EngineeringWater ManagementCivil Engineering and Geoscience
