Chemigation with Micronized Sulfur Rapidly Reduces Soil pH in a New Planting of Northern Highbush Blueberry

Northern highbush blueberry (Vaccinium corymbosum L.) is adapted to acidic soil conditions and often grows poorly when soil pH is greater than 5.5. When soil pH is high, growers will usually mix prilled elemental sulfur (So) into the soil before planting (converted to sulfuric acid by soil bacteria) and, if needed, inject acid into the irrigation water after planting. These practices are effective but often expensive, time consuming, and, in the case of acid, potentially hazardous. Here, we examined the potential of applying micronized So by chemigation through a drip system as an alternative to reduce soil pH in a new planting of ‘Duke’ blueberry. The planting was located in western Oregon and established on raised beds mulched with sawdust in Oct. 2010. The So product was mixed with water and injected weekly for a period of ≈2 months before planting and again for period of ≈2 months in late summer of the second year after planting (to assess its value for reducing soil pH once the field was established), at a total rate of 0, 50, 100, and 150 kg·ha−1 So on both occasions. Each treatment was compared with the conventional practice of incorporating prilled So into the soil before planting (two applications of 750 kg·ha−1 So each in July and Oct. 2010). Within a month of the first application of So, chemigation reduced soil pH (0–10 cm depth) from an average of 6.6 with no So to 6.1 with 50 kg·ha−1 So and 5.8 with 100 or 150 kg·ha−1 So. However, the reductions in pH were short term, and by May of the following year (2011), soil pH averaged 6.7, 6.5, 6.2, and 6.1 with each increasing rate of So chemigation, respectively. Soil pH in the conventional treatment, in comparison, averaged 6.6 a month after the first application and 6.3 by the following May. In July 2012, soil pH ranged from an average of 6.4 with no So to 6.2 with 150 kg·ha−1 So and 5.5 with prilled So. Soil pH declined to as low as 5.9 following postplanting So chemigation and, at lower depths (10–30 cm), was similar between the treatment chemigated with 150 kg·ha−1 So and the conventional treatment. None of the treatments had any effect on winter pruning weight in year 1 or on yield, berry weight, or total dry weight of the plants in year 2. Concentration of P, K, Ca, Mg, S, and Mn in the leaves, on the other hand, was lower with So chemigation than with prilled So during the first year after planting, whereas concentration of N, P, and S in the leaves were lower with So chemigation during the second year. The findings indicate that So chemigation can be used to quickly reduce soil pH after planting and therefore may be a useful practice to correct high pH problems in established northern highbush blueberry fields; however, it was less effective and more time consuming than applying prilled So before plantin

Energetic and exergetic analysis of combined cycle power plant: Part-1 operation and performance

Energetic and exergetic analyses are conducted using operating data for Sabiya, a combined cycle power plant (CCPP) with an advanced triple pressure reheat heat recovery steam generator (HRSG). Furthermore, a sensitivity analysis is carried out on the HRSG using a recent approach to differentiate between the sources of irreversibility. The proposed system was modelled using the IPSEpro software and further validated by the manufacturer’s data. The performance of the Sabiya CCPP was examined for different climatic conditions, pressure ratios, pinch point temperatures, high-pressure steam, and condenser pressure values. The results confirmed that 60.9% of the total exergy destruction occurs in the combustion chamber, which constitutes the main source of irreversibilities within a system. The exergy destruction was significantly affected by both the pressure ratio and the high-pressure steam, where the relation between them was seen to be inversely proportional. The high-pressure stage contributes about 50% of the exergy destruction within the HRSG compared to other stages and the reheat system, due to the high temperature difference between the streams and the large number of components, which leads to high energy loss to the surroundings. Numerous possibilities for improving the CCPP’s performance are introduced, based on the obtained results

Exergetic, exergoeconomic and exergoenvironmental analysis of intercooled gas turbine engine

Exergetic and exergoeconomic and exergoenvironmental analyses have been performed for an advanced aero-derivative intercooled gas turbine engine. The proposed system was modelled using the IPSEpro software package and validated using manufacturer’s published data. The exergoeconomic model evaluates the cost-effectiveness of the gas turbine engine based on the Specific Exergy Costing [SPECO] method. The CO2 emissions per KWh were estimated using a generic combustor model, HEPHAESTUS, developed at Cranfield University. It is well known that the exergetic analysis can determine the magnitudes, locations and types of losses within an energy system. The effect of load and ambient temperature variations on gas turbine performance were investigated for two different configurations. The first system, Case-I, was a simple gas turbine (SCGT) engine, and the second, Case-II, an intercooling gas turbine (ICGT) system. The latter enhances gas turbine efficiency but, at the same time, has an adverse effect on the combustion chamber due to reduced compressed air temperature. It was confirmed that full load and low ambient temperature are preferable due to the low waste exergy. The unit exergy cost rate for both SCGT and ICGT have been calculated as 8.59 and 8.32 US$/GJ respectively. The exergoenvironmental results show the ICGT achieved lower emission levels and is more environmentally friendly than the SCGT

Ergonomic Immobilization Frame for Radiotherapy

The primary purpose of this project is to demonstrate that patients can be safely immobilized using air in the general torso area so that radiation can be administered to that region. The primary target will be to treat tumors in the lungs and liver. By immobilizing patients during treatment it allows for the radiation to be consistent in targeting the desired region of the body, which would not be the case if the patient was moving. Air was chosen as the desired medium to immobilize the patient because of comfort and it provides an easy medium for radiation to travel through which does not interfere with the radiation. Through research the limiting factor of human body was the pulmonary cycle which was determined to be approximately 0.15 Psi. In order to use air for immobilization airbags were incorporated as a means to hold the air and once pressurized would be used as the restraint force on the patient. As a means to demonstrate that air in fact could be used to immobilize a patient a prototype of a radiation chamber was built to provide a proof of concept. The radiation chamber frame was built to completely encapsulate the patient 360 degrees. The two airbags were placed in the frame which provides complete immobilization of the patient from all angles. The patient had to be standing while the radiation was being administered in order to target certain areas which could not be included if the patient was sitting or lying down. A circular frame was the desired shape of the frame because it allows for radiation to enter and exit the chamber at the same angle regardless of where it is administered. The radiation chamber requires the use of radiation safe materials in any given area where the frame comes into contact with radiation, for this reason non-metallic materials were used. The chamber prototype was built using wood and plexiglass. Finite element analysis simulated an allowable applied pressure of 6.0 Psi applied to the shell. Prior to the given prototype, there was no means available to immobilize a patient while standing for radiotherapy. Experimental tests demonstrated that a person could be immobilized in the general torso area using air.https://scholarscompass.vcu.edu/capstone/1214/thumbnail.jp

Synthetic studies towards multichromophore arrays

The overall aim of this project was to investigate strategies for linking macrocyclic chromophores to form arrays. Firstly the aim was to link a porphyrin to a triphenylene through phenyl alkynes. Interestingly, this study discovered a mesogenic dibromtetramethoxy triphenylene – the least heavily substituted triphenylene liquid crystal reported to date. The results of this investigation, however, show that, in general, it was challenging to force the reaction between porphyrin and triphenylene components to form acetylene links. Dimerization of the acetylene components was observed as the predominant reaction in all cases. However, it was possible to isolate a porphyrin-triphenylene dyad structure. The second aim of this study was to investigate the synthesis of novel chromophore dyads and triads 102, 104 and 134 which are based on porphyrin and tetrabenzotriazaporphyrin (TBTAP) components. The first aim was to synthesise porphyrin–phenyl-TBTAP 102. A precursor porphyrin bearing aminoisoindoline functionality was successfully prepared. However, it could not be converted to either the porphyrin–phenyl-TBTAP 102 dyad or porphyrin-azaBODIPY-porphyrin triad 134. On the other hand, the suggested strategy towards the synthesis of porphyrin-TBTAP dyads linked through flexible chains (104) remains promising. Magnesium TBTAB-OH 135 was synthesised as one important reactant. However, the unfortunate choice of bromododecyloxyporphyrin 141, meant the synthesis of the desired dyad could not be achieved within this project because it could not be separated from excess dibromododecane. However, simple modification of the strategy (e.g using bromododecanol) will allow the compounds to be prepared in the future

Algorithms for Multi-Sample Cluster Analysis

In this study, we develop algorithms to solve the Multi-Sample Cluster Analysis (MSCA) problem. This problem arises when we have multiple samples and we need to find the statistical model that best fits the cluster structure of these samples. One important area among others in which our algorithms can be used is international market segmentation. In this area, samples about customers’preferences and characteristics are collected from di¤erent regions in the market. The goal in this case is to join the regions with similar customers’characteristics in clusters (segments). We develop branch and bound algorithms and a genetic algorithm. In these algorithms, any of the available information criteria (AIC, CAIC, SBC, and ICOMP) can be used as the objective function to be optimized. Our algorithms use the Clique Partitioning Problem (CPP) formulation. They are the first algorithms to use information criteria with the CPP formulation. When the branch and bound algorithms are allowed to run to completion, they converge to the optimal MSCA alternative. These methods also proved to find good solutions when they were stopped short of convergence. In particular, we develop a branching strategy which uses a look-ahead technique. We refer to this strategy as the complete adaptive branching strategy. This strategy makes the branch and bound algorithm quickly search for the optimal solution in multiple branches of the enumeration tree before using a depth- first branching strategy. In computational tests, this method’s performance was superior to other branching methods as well as to the genetic algorithm

3d Solid Modeling and Pre-Static Finite Element Modeling of Intact Human Tibia

This paper presents a standard solid model for human tibia, accounting for the material characteristics of cortical bone, cancellous bone and bone marrow. A CT scan of a cadaveric human tibia was used as the basis of developed model. A total of 201 CT scan slices of the tibia were taken with the distances between the scans varying along the length of the bone with a higher density at the proximal and distal ends, as those were the regions of interest. The data was imported into MIMICS (Materialise), and the threshold method was used to differentiate between the cortical bone region, cancellous bone region, and the bone marrow cavity. The solid model used to generate the FE model is constructed based on CT scan data of an actual cadaveric human tibia. The geometric information is retrieved and edited in (MIMICS). The surfaces defining the cortical bone, the proximal and distal epiphyseal cancellous bone and medullar cavity regions are converted into NURBS surfaces using (GEOMAGIC STUDIO)

Sustainability of Utilizing Renewable and Nuclear Energy in Saudi Arabia Using Different Types of Life Cycle Assessment

Evaluating the global environmental impacts of the current and future energy policies in Saudi Arabia using Life cycle assessment (LCA) method was the main objective of this dissertation. First, the attributional life cycle assessment (ALCA) framework was used to evaluate the Saudi’s air conditioning systems, as they are responsible for about 70% of the total Saudi residential electricity consumption. The ALCA’s results showed that the AC use phase produces the largest share of the environmental impact and the magnitude of the environmental impacts is influenced by the type of primary fuel used for electricity generation. Emerging non-fossil sources of electricity may be the intuitive solution to reduce environmental impacts. Saudi Arabia has an ambitious plan to meet 50% of its electricity needs with renewable and nuclear energy. Implementing this plan will free up more of the Saudi oil for export, affecting the country and the rest of the world, since Saudi is the world largest oil exporter. To predict global economic shifts that would be triggered by that plan, a modified version of well-known computable general equilibrium (CGE) model, the Global Trade Analysis Project (GTAP), was used. The study showed that fossil fuel energy prices and ease of substitution for the fossil fuel electricity technologies are the main drivers for the emergence of renewable and nuclear energy. As the GTAP’s CO2 emissions data only account for burned fossil fuels, there is a need to perform the study using a comprehensive method. That was done by performing a consequential perspective LCA. The results of this LCA showed that harmful environmental impacts would be reduced in Saudi Arabia. For the rest of the world, the impacts were largely negative. Finally, an ex-ante analysis was done to study the economic, social and environmental impacts of large-scale global electricity generation targets to utilize renewable and nuclear energy by 2030. The study showed a deteriorated GDP in most regions. The world would face a loss of 4.45 million jobs. The environment benefits of the targeted renewable and nuclear energy would be slight and not enough to mitigate the global temperature rise

The Assessment Strategy for Selecting and Evaluating Geoenvironmental Remediation

A large volume of oil-contaminated sand remains in the Kuwaiti deserts, causing threat to the groundwater and ecological system. The main aims of this research are to evaluate the situation of Kuwaiti oil lakes and identify the impact of contaminated soil on ecology and humans in Kuwait. This consists of two phases; the first phase summarises the results from field demonstrations and discusses the prospective of using different techniques for remediation of the oil-contaminated soil in Kuwait, while the second phase aims to compare and select the appropriate soil remediation techniques based on UN requirements. In this chapter, decision mechanism was carried out in compliance with the House of Quality (HOQ) analysis system. The total weighted score for each soil remediation method was determined to obtain the final decision