Experimental analysis of a four slope solar still augmented with a parabolic reflector array with V-shaped mirror arrangement for pre-heating brackish water

The primary motive for large transmit array of parabolic reflectors, also known as uplink array, was to explore alternate methods in order to replace the large 70m antennas of deep space network (DSN) such that the core capability for emergency support to a troubled spacecraft in deep space is preserved. Given that the Uplink Array is a new technology, the focus has always been on its feasibility and phase calibration techniques, which by itself is quite a challenge. It would be interesting to examine, however, what else could be accomplished by the uplink array capability other than the emergency support to a troubled spacecraft in deep space. Although the uplink array calibration and demonstration for proof of concept is still underway at Jet Propulsion Laboratory (JPL), knowledge of various potential meaningful application scenarios as well as operation concepts of uplink array is equally important to better understand and fine tune the high level architectural requirements of this big evolving system of systems. Therefore, the objective of this paper is to discuss a few application scenarios and the corresponding operation concepts, such as lunar positioning system, high EIRP uplink and the synergies with solar system radar, and high power RF beams

The present study analyzes the economic viability of an Integrated Energy System (IES) that couples a Reverse Osmosis (RO) water desalination facility with a Nuclear Power Plant (NPP). The case study is conducted in collaboration with Arizona Public Service (APS), the operating owner of the Palo Verde Generating Station (PVGS) NPP. A challenge APS is facing is that their cooling water acquisition contract with the Sub Regional Operating Group (SROG) will expire soon and a renewal can only be done for a significantly higher price of the water. Therefore, APS is seeking alternative sources for their cooling water. One opportunity is to pump brackish water from the regional ground water. Although much less expensive than the water from the new SROG contract, the salinity of the brackish water is so high that a blend of brackish and SROG water will need additional treatment to improve its quality for use in the PVGS cooling towers. A study has been conducted in 2018 at Idaho National Laboratory (INL) to investigate the economics of an PVGS onsite RO desalination plant that would reduce the salinity of a SROG and brackish water blend to an acceptable level. One of the main findings of that study was that the overall economics of water desalination can be greatly improved if, in addition to cooling water for PVGS, potable water could also be produced and sold for profit. In fact, the study concluded that only producing cooling water for PVGS via RO desalination is not economically viable compared to buying all needed cooling water from the SROG. The present report investigates the economic impact of a large, regional RO desalination plant that could provide potable water for the region, considering the conclusions from last year’s scoping study. The study looks in particular at the water-market situation in the West Valley of Phoenix; i.e., in the area of the municipalities of Buckeye, Goodyear, Avondale and Tolleson. In addition to providing potable water for the adjacent municipalities, the concentrate from the regional RO plant would be taken and treated by PVGS to provide some cooling water for a (hopefully) lower cost than that of the SROG water. Furthermore, a cost structure could be put in place for the treatment of the concentrate from the regional RO that would offset some of the water acquisition cost for APS. The analysis used the Nuclear-Renewable Hybrid Energy System (N-R HES) software framework, which was developed at INL in 2016. The framework has reached some level of maturity, such that it can be applied to more than simple demonstration cases; i.e., real industry problems. The analysis in this report considers two cases (for various scenarios): First, the Base Case is the most economic one for APS, as no RO is built, i.e. the case for which cooling water acquisition and treatment cost are lowest. The 2018 INL study showed that some brackish water can be blended with the effluent SROG water without having to build the onsite RO. The Base Case is where APS pumps the maximum volume of less-expensive brackish water (limited by water chemistry in the cooling towers), blends it with the effluent from the SROG, and no RO is built. Second, the proposed RO Case includes two RO plants, one onsite at PVGS and another larger, regional one close to the brackish water wells. The regional RO produces potable water that is sold to the regional municipalities, while the PVGS RO onsite treats (part of) the regional ROs' concentrate and brackish water blend. The desalinated water from the PVGS RO is used in the cooling towers at PVGS. The analysis evaluates the difference in economics, using the Net Present Value (NPV) and Internal Rate of Return (IRR), between the cases. By comparing the two cases, in addition to evaluating the economics of the regional RO, we can also assess the impact of the regional RO on PVGS and consequently APS economics. The study shows that (for the Base Case) to offset the treatment cost for the RO concentrate, the cost of concentrate treatment to be paid by the regional RO to APS would be between 5 – 35 $/m3 of concentrate (depending on the regional RO size envisaged). Correspondingly, the Levelized Cost of Potable Water (LCOPW), which is the average or unit cost, for the regional RO is in the 0.55 – 0.6 $/m3 range of potable water. Or, considering the residential water demand model developed for the Phoenix West Valley, the NPV of the regional RO would be between $20 and 100 billion.

The characteristics of an X-ray detection system based on an array of parabolic reflectors that provide a line-shaped focus will be described. The most recent rocket instrument has an overall length of about two meters and utilizes a pair of thin-window gas-flow proportional counters for detecting the X-rays. The variation of effective aperture with X-ray energy, the amount of scattering from the mirror surfaces, and the quality of the optical focus will be discussed. Estimates of the sensitivity of a larger set of X-ray optics used as a survey system, and when combined with a special grating to form a spectrograph, will be presented.

This article presents a feasibility study of single feed per beam quasi-optical (QO) antennas for enabling incoherent multiple-input multiple-output (MIMO) array front-end architectures at 270 GHz. The objective is to reach ultrafast and radiated energy efficient point-to-point (PtP) wireless links by exploiting the multimode capacity of radiative (Fresnel region) near-field links. In this article, we present a feasibility study of the number of independent links achievable with QO MIMO incoherent arrays. For this purpose, we present theoretical curves of the level of EM co-coupling and interference between the multiple modes versus the link distance. The study focuses at the 252–325 GHz spectral bandwidth defined by the new IEEE 802.15.3d standard. A specific and new MIMO array architecture operating at 270 GHz based on a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2 \times 2$ </tex-math></inline-formula> array of parabolic reflectors is proposed for a link distance of 100 m. The proposed PtP MIMO system is capable of generating 16 dual-polarized modes in a 70 GHz bandwidth with signal-to-interference ratio >17 dB and a power co-coupling coefficient of −3 dB without the need for interference cancelation techniques. Combining this architecture with wideband front ends could potentially lead to an aggregated data rate in the order of terabit per second in a PtP wireless line-of-sight link, not previously achieved experimentally to the best of authors’ knowledge.

The Sultanate of Oman lies in an arid region where fresh water sources are scarce. Economic and population growth spur the need for more housing, schools, roads, and many other civil works. In the construction of such projects, water is needed as a component in concrete mixing. Contractors in arid regions are sometimes faced with the problem of finding water of acceptable quality for their construction work. However, plenty of production water (oily and brackish water) is produced in the oil fields during oil production. In 2002, Petroleum Development Oman (PDO) produced an estimated 130,000 m3/day of crude oil with a corresponding 630,000 m3/day of production water, most of which are disposed of via deep well injection. This research project was initiated as a possible option for the use of production water as part of PDO’s policy on sustainable development, materials efficiency, and waste reduction. The main objective of this paper is to present the results obtained on the use of production (oily) and brackish water in concrete mixtures. Water samples were obtained from four PDO asset areas. Nine water samples, including a controlled potable (tap) water, were analysed for pH, total dissolved solids (TDS), chloride, hardness, alkalinity, and sulphates. In addition, cement pastes and mortars and plain concrete mixtures were prepared using 100% substitution of potable water. Nine mixtures were prepared and cured for up to one and a half years. Mixtures were tested for initial setting times, compressive strength and flexural strength. Research results indicate that there was a small decrease in the initial setting times for all cement paste mixtures prepared using production and brackish water in comparison with potable water. However, such values still exceeded the minimum 45 minutes initial setting requirement as set forth in ASTM C150. The use of PDO’s production and brackish water did not cause any decrease in the compressive or flexural strength measurements of cement mortars or concrete mixtures in comparison with potable water. In general, there was no strength reversal with longer curing periods. However, for most concrete mixtures the strength tends to level off after three months of curing. Most production water mixtures resulted in higher strength measurements than those prepared using potable water. Further testing is necessary to investigate corrosion potential in reinforced concrete.

The number of reproductive units is expected to grow exponentially in the absence of regulating feedbacks. The lack of feedbacks is a definitive assumption of any model predicting exponential growth, be it individual- or population-based, discrete or continuous, deterministic or stochastic. The exponential growth of a population can be characterised by its long-term per capita rate of increase (population growth rate, pgr) in any actual representation. Exponential growth with a constant pgr will occur whenever the stochastic changes in the environmental conditions—including modifying and regulating ones—affecting births and deaths are stationary in the long run. Case studies indicate that temporary periods of exponential population increase or decline must be regular in nature, and pgrs may show remarkable temporal and spatial invariance.

AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials AME 61:141-148 (2010) - DOI: https://doi.org/10.3354/ame01444 Hemolytic toxicity and nutritional status of Prymnesium parvum during population growth Theodore R. Skingel1,2, Sandra E. Spencer1, Cuong Q. Le1, Carlos A. Serrano1, Laura D. Mydlarz3, Betty J. Scarbrough3, Kevin A. Schug1,2, Bryan W. Brooks4, James P. Grover2,3,* 1Department of Chemistry and Biochemistry, and 2Program in Environmental and Earth Sciences, University of Texas at Arlington, Box 19065, Arlington, Texas 76019, USA 3Department of Biology, University of Texas at Arlington, Box 19498, Arlington, Texas 76019, USA 4Department of Environmental Science and Center for Reservoir and Aquatic Systems Research, Baylor University, One Bear Place #97266, Waco, Texas 76798, USA *Corresponding author. Email: grover@uta.edu ABSTRACT: The haptophyte flagellate Prymnesium parvum forms blooms in brackish waters and produces toxins that harm aquatic organisms. Batch cultures of P. parvum were grown in phosphorus-limited artificial seawater medium with 3 treatments: no aeration or buffering, continuous aeration, and buffering to a high, basic pH. Over a period of 32 d, frequent samples were taken to determine: cell abundance; cellular composition of carbon (C), nitrogen (N), and phosphorus (P); culture pH; and hemolytic activity. Only pH differed significantly among media treatments: it was basic in all treatments after 10 d of culture, but consistently highest in the buffered medium treatment. In all treatments, exponential population growth was observed during the first 10 d of culture, at rates of about 0.4 to 0.6 d–1. The cell quota for P declined rapidly over the first 8 d of culture and more slowly thereafter. A transition from exponential growth to stationary phase occurred over 10 to 21 d of culture. Population growth rate was related to cell quota for P according to Droop’s equation, with an estimated quota for zero growth of about 5 fmol cell–1. In all cultures, high hemolytic activity was seen on Days 8 and 12. All but one culture displayed oscillations of hemolytic activity thereafter. At times of high hemolytic activity, the cell quota for P was <100 fmol cell–1 and the cellular C:P ratio was at or above the Redfield ratio of 106. KEY WORDS: Harmful algae · Phytoplankton · Blooms · Toxins · Cell quota · Nutrient limitation · Phosphorus Full text in pdf format PreviousNextCite this article as: Skingel TR, Spencer SE, Le CQ, Serrano CA and others (2010) Hemolytic toxicity and nutritional status of Prymnesium parvum during population growth. Aquat Microb Ecol 61:141-148. https://doi.org/10.3354/ame01444 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in AME Vol. 61, No. 2. Online publication date: October 01, 2010 Print ISSN: 0948-3055; Online ISSN: 1616-1564 Copyright © 2010 Inter-Research.

Influence of water mass on the performance of spherical basin solar still integrated with parabolic reflector

Prefaces - Exponential Population Growth - Logistic Population Growth - Age-Structured Population Growth - Metapopulation Dynamics - Competition - Predation - Island Biogeography - Succession - Problems - Appendix: Working with Differential Equations - Solutions to Problems - Glossary - Literature Cited - Index

The technology of solar still shows up as an effective and affordable solution to convert available brackish water into potable water. The present study aims to address the challenge of providing freshwater by desalinating brackish water using solar energy. An attempt has been made in this work to make a desalination system for the efficient utilization of solar energy by using a parabolic reflector and energy‐storage material. Modification in the desalination system and storage of energy facilitates the continuation of the process in sunshine and off‐sunshine hours which increases yield output. To investigate the objectives, helical‐shaped focal tubes and nano‐enhanced phase change material (PCM) are prepared. The desalination system is coupled with nano‐enhanced PCM by placing it in the annular space of a helical‐shaped focal tube. The heat transfer coefficient ranged from 11.46 to 28.77 W/(m² K). PCM 3 (i.e., base PCMs with 1.5% nanoadditives) achieved a maximum productivity of 3533.3 mL/m²/day, marking a 97.89% improvement over the system without PCM. The preheated water outlet temperature reached 67.4°C, and the basin water temperature was 75.35°C. The highest concentrator efficiency recorded was 49.82% at a mass flow rate of 0.0053 kg/s. Thermodynamic analysis showed a 67.19% enhancement in overall thermal efficiency with PCM 3 compared with the non‐PCM scenario. Additionally, the system attained a maximum average exergy efficiency of 12.29% and the shortest payback period of 115 days. The study concludes that the base PCM sample with a 1.5% mass concentration of nanoparticles was optimal.

Long distance communication has developed leaps and bounds where it is possible to communicate across the solar system and beyond. This demands the use of large antennas with very high gain for successful link between the transmitter and receiver. To achieve this, in the recent times a new category of antennas have emerged having low mass and low profile. This type of antenna is known as the Reflect Array. This provides low cost and high gain solution. The reflect array combines the favorable features of reflectors and printed arrays. The parabolic dish is difficult to fabricate with tight tolerances at mm wave frequencies, in the case of the conventional phased arrays it is very expensive due to the presence of thousands of T/R modules to obtain the high gain required. Hence the reflect arrays are gaining more attention as an alternative to more mature technologies in the Synthetic Aperture Radar (SAR) Applications as it mitigates the drawbacks of these two types of antennas. In this paper a 1616 element offset fed array is designed at Ku-band. Feed horn is designed using CST Microwave studio, 400mm diameter reflect array is designed that consists of rectangular patches using Ansoft HFSS and the reflect array as a whole is simulated using Integral Equation Method in CST. The phase compensation is performed by varying the patch width and keeping the length fixed at resonance. The simulated gain for the offset fed reflect array is 31.3 dB and the measured gain is 30.5 dB.

Corrosion fatigue of carbon steel 1018 and 4140 was studied in three types of water in Kuwait, potable, brackish and sea water using a rotary fatigue bending machine with a corrosion chamber attached. Results have shown that fatigue strength of both steels is reduced much more in potable water than in brackish water, with maximum reduction occurring in seawater. The low alkalinity and chemical instability of the potable water in Kuwait is a factor that influences the corrosion fatigue of such carbon steels.

Analysis of desalination alternates for phosphoric acid plant in Tunisia

A hybrid machine learning and embedded IoT-based water quality monitoring system

The world demand for potable water is increasing steadily with growing population.Desalination using solar energy is suitable for potable water production from brackish and seawater.In this paper, we presents design, fabrication and testing of double slope solar still with external flatted and internal parabolic reflectors and also optimization of external flat reflector tilt angle for Egyptian climatic conditions.The external flat reflector tilted at (30°, 45°, 60° and 75°) on the horizontal plane.The depth of water inside basin still is 1cm.Experimental results were compared with conventional double slope solar still.Optimum tilt angle is found to be 60° with a maximum daily productivity of 9.89 lit/m 2 .