scholarly journals Multistage and passive cooling process driven by salinity difference

2020 ◽  
Vol 6 (11) ◽  
pp. eaax5015
Author(s):  
Matteo Alberghini ◽  
Matteo Morciano ◽  
Matteo Fasano ◽  
Fabio Bertiglia ◽  
Vito Fernicola ◽  
...  
Keyword(s):  
Temperature Difference ◽  
Cost Effective ◽  
Cooling Capacity ◽  
Passive Cooling ◽  
Proof Of Concept ◽  
Hydrophobic Membrane ◽  
Vapor Flux ◽  
Salinity Gradients ◽  
Space Cooling ◽  
Salinity Difference

Space cooling in buildings is anticipated to rise because of an increasing thermal comfort demand worldwide, and this calls for cost-effective and sustainable cooling technologies. We present a proof-of-concept multistage device, where a net cooling capacity and a temperature difference are demonstrated as long as two water solutions at disparate salinity are maintained. Each stage is made of two hydrophilic layers separated by a hydrophobic membrane. An imbalance in water activity in the two layers naturally causes a non-isothermal vapor flux across the membrane without requiring any mechanical ancillaries. One prototype of the device developed a specific cooling capacity of up to 170 W m−2 at a vanishing temperature difference, considering a 3.1 mol/kg calcium chloride solution. To provide perspective, if successfully up-scaled, this concept may help satisfy at least partially the cooling needs in hot, humid regions with naturally available salinity gradients.

Flow Channelization Method to Enhance Transformer Radiator Cooling Capacity

2018 ◽  
Vol 10 (6) ◽  
Author(s):  
Subhashish Dasgupta ◽  
Anurag Nandwana ◽  
K. Ravikumar
Keyword(s):  
Natural Convection ◽  
Heat Exchangers ◽  
Fluid Dynamic ◽  
Cost Effective ◽  
Cooling Capacity ◽  
Structural Features ◽  
Cfd Analysis ◽  
Cooling Process ◽  
Effective Technology ◽  
Convection Cooling

Abstract Most oil-cooled equipment like transformers are provided with radiators or heat exchangers, for the heated oil to exchange heat with the surrounding air by natural convection cooling, assisting the overall cooling process. While such radiators are effective accessories in controlling equipment temperature rise, it is ever desirable to further enhance the cooling capacity by design modifications or incorporating simplistic and cost-effective cooling technologies. In this study, computational fluid dynamic (CFD) analysis has been performed to evaluate the possibility of improving radiator performance by flow channelizing structures. Significant benefits (up to 17% increase in heat transfer coefficient) of imposing such structures, like a top chimney and an enclosure surrounding the radiator, were obtained. Although several past studies have confirmed that natural convection cooling effect can be intensified by flow channelization, the phenomenon is unique to a particular application. Given the wide variety in applications, in terms of shape, size, and structural features, it is necessary to study the effect in a given application of interest. This study points to a new direction in enhancing the cooling capacity of transformer radiators, inducing flow channelization, an easy-to-implement and cost-effective technology. Further, the study offers interesting learnings regarding flow channelization effects, which are invaluable guidelines for designers of future radiators.

Morphological Study of Fabricated PVDF Based Hydrophobic Membrane for Different Additives and Coagulation Bath Temperature

2021 ◽  
Vol 18 (3) ◽  
pp. 39-47
Author(s):  
Meenakshi Yadav ◽  
Sushant Upadhyaya ◽  
Kailash Singh ◽  
Manish Vashishtha
Keyword(s):  
Contact Angle ◽  
Water Content ◽  
Temperature Difference ◽  
Synergistic Effects ◽  
Weight Percent ◽  
Membrane Distillation ◽  
Coagulation Bath ◽  
Hydrophobic Membrane ◽  
Sem Micrograph ◽  
Dope Solution

The demand of membrane distillation (MD) has increased since last few decades for numerous applications. The membrane used in MD is hydrophobic; therefore, the focus has been emphasised on the development of a suitable membrane with desired microstructure. In this study, the flat sheet hydrophobic membrane of suitable properties has been casted with various additives such as water, ethane-di-ol, and propan-2-ol in dope solution using a non-solvent induced phase separation (NIPS) technique. The effect of water content in dope solution has been studied on casted membrane porosity and contact angle. The maximum contact angle and porosity were found to be 96° and 53.23% at 4 weight percent of water content in dope solution of PVDF polymer and di.methyl.acetamide as solvent. It was found that SEM micrograph when ethane-di-ol and propan-2-ol are used as an additive shows more finger-like pores and nodules, respectively, in the microstructure of the casted membrane. Furthermore, synergistic effects using water with other additives were also identified using SEM micrograph of casted membrane and it was observed that water with ethane-di-ol and propan-2-ol form contact angle of 98° and 105°, respectively, for 2 weight percent each additive in dope. In this study, the membrane was also cast by dissolving PVDF powder in di.methyl.acetamide solvent with lithium chloride and the effect of the temperature difference between coagulation bath and film temperature was investigated using an SEM micrograph. Overall, it was found that water content and temperature difference aid in developing hydrophobic porous membrane of desired properties for MD applications.

scholarly journals Repurposing Butenafine as An Oral Nanomedicine for Visceral Leishmaniasis

Pharmaceutics ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 353 ◽  
Author(s):  
Adriana Bezerra-Souza ◽  
Raquel Fernandez-Garcia ◽  
Gabriela F. Rodrigues ◽  
Francisco Bolas-Fernandez ◽  
Marcia Dalastra Laurenti ◽  
...  
Keyword(s):  
Drug Stability ◽  
Drug Loading ◽  
Cost Effective ◽  
Angle Of Repose ◽  
Proof Of Concept ◽  
Flow Properties ◽  
Non Invasive ◽  
Long Duration ◽  
Effective Drugs ◽  
Spray Dried

Leishmaniasis is a neglected tropical disease affecting more than 12 million people worldwide, which in its visceral clinical form (VL) is characterised by the accumulation of parasites in the liver and spleen, and can lead to death if not treated. Available treatments are not well tolerated due to severe adverse effects, need for parenteral administration and patient hospitalisation, and long duration of expensive treatments. These treatment realities justify the search for new effective drugs, repurposing existing licensed drugs towards safer and non-invasive cost-effective medicines for VL. In this work, we provide proof of concept studies of butenafine and butenafine self-nanoemulsifying drug delivery systems (B-SNEDDS) against Leishmania infantum. Liquid B-SNEDDS were optimised using design of experiments, and then were spray-dried onto porous colloidal silica carriers to produce solid-B-SNEDDS with enhanced flow properties and drug stability. Optimal liquid B-SNEDDS consisted of Butenafine:Capryol 90:Peceol:Labrasol (3:49.5:24.2:23.3 w/w), which were then sprayed-dried with Aerosil 200 with a final 1:2 (Aerosil:liquid B-SNEDDS w/w) ratio. Spray-dried particles exhibited near-maximal drug loading, while maintaining excellent powder flow properties (angle of repose <10°) and sustained release in acidic gastrointestinal media. Solid-B-SNEDDS demonstrated greater selectivity index against promastigotes and L. infantum-infected amastigotes than butenafine alone. Developed oral solid nanomedicines enable the non-invasive and safe administration of butenafine as a cost-effective and readily scalable repurposed medicine for VL.

Efficient two-stage sequential arrays of proof of concept studies for pharmaceutical portfolios

2020 ◽  
pp. 096228022095817
Author(s):  
Linchen He ◽  
Linqiu Du ◽  
Zoran Antonijevic ◽  
Martin Posch ◽  
Valeriy R Korostyshevskiy ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Cost Benefit ◽  
Cost Effective ◽  
Cost Ratio ◽  
Proof Of Concept ◽  
Type Iii ◽  
Benefit Cost Ratio ◽  
Stage 1 ◽  
Two Stages ◽  
Benefit Cost

Previous work has shown that individual randomized “proof-of-concept” (PoC) studies may be designed to maximize cost-effectiveness, subject to an overall PoC budget constraint. Maximizing cost-effectiveness has also been considered for arrays of simultaneously executed PoC studies. Defining Type III error as the opportunity cost of not performing a PoC study, we evaluate the common pharmaceutical practice of allocating PoC study funds in two stages. Stage 1, or the first wave of PoC studies, screens drugs to identify those to be permitted additional PoC studies in Stage 2. We investigate if this strategy significantly improves efficiency, despite slowing development. We quantify the benefit, cost, benefit-cost ratio, and Type III error given the number of Stage 1 PoC studies. Relative to a single stage PoC strategy, significant cost-effective gains are seen when at least one of the drugs has a low probability of success (10%) and especially when there are either few drugs (2) with a large number of indications allowed per drug (10) or a large portfolio of drugs (4). In these cases, the recommended number of Stage 1 PoC studies ranges from 2 to 4, tracking approximately with an inflection point in the minimization curve of Type III error.

Beyond green façades: active air-cooling vertical gardens

2019 ◽  
Vol 8 (3) ◽  
pp. 243-252 ◽  
Author(s):  
Michael Maks Davis ◽  
Andrea Lorena Vallejo Espinosa ◽  
Francisco Rene Ramirez
Keyword(s):  
Design Methodology ◽  
Cooling Capacity ◽  
Urban Environments ◽  
Passive Cooling ◽  
Air Cooling ◽  
Climate Control ◽  
Content Type ◽  
Air Inlet ◽  
Water Saturated ◽  
Monteith Equation

Purpose Vertical gardens offer multiple benefits in urban environments, including passive cooling services. Previous research explored the use of “active vertical gardens” as potential evaporative air-cooling units by developing a mathematical model based on the FAO-56 Penman Monteith equation. Further research showed that active vertical gardens function best by creating an airflow in the cavity behind the garden such that air is cooled by flowing over the water-saturated garden substrate. The purpose of this paper is to improve the quantification of active vertical garden performance. Design/methodology/approach A building-incorporated vertical garden was built in Quito, Ecuador, with an air inlet at the top of the garden, an air cavity behind the garden and where air was expelled from the base. Measurements were made of air temperature, humidity and velocity at the air inlet and outlet. Findings The active vertical garden cooled the air by an average of 8.1 °C with an average cooling capacity of 682.8 W. Including the effects of pre-cooling at the garden inlet, the garden cooled the air by an average of 14.3 °C with an average cooling capacity of 1,203.2 W. Originality/value The results are promising and support the potential for active vertical gardens to be incorporated into building services and climate control.

Coupled Multi-Material and Joint Topology Optimization: A Proof of Concept

2018 ◽  
Author(s):  
Vlad Florea ◽  
Vishrut Shah ◽  
Stephen Roper ◽  
Garrett Vierhout ◽  
Il Yong Kim
Keyword(s):  
Topology Optimization ◽  
Cost Effective ◽  
Material Design ◽  
Optimization Methods ◽  
Manufacturing Constraints ◽  
Proof Of Concept ◽  
Efficient Design ◽  
Engineering Costs ◽  
Increasing Demand ◽  
Material Layout

Over the past decade there has been an increasing demand for light-weight components for the automotive and aerospace industries. This has led to significant advancement in Topology Optimization methods, especially in developing new algorithms which can consider multi-material design. While Multi-Material Topology Optimization (MMTO) can be used to determine the optimum material layout and choice for a given engineering design problem, it fails to consider practical manufacturing constraints. One such constraint is the practical joining of multi-component designs. In this paper, a new method will be proposed for simultaneously performing MMTO and Joint Topology Optimization (JTO). This algorithm will use a serial approach to loop through the MMTO and JTO phases to obtain a truly optimum design which considers both aspects. A case study is performed on an automotive ladder frame chassis component as a proof of concept for the proposed approach. Two loops of the proposed process resulted in a reduction of components and in the number of joints used between them. This translates into a tangible improvement in the manufacturability of the MMTO design. Ultimately, being able to consider additional manufacturing constraints in the Topology Optimization process can greatly benefit research and development efforts. A better design is reached with fewer iterations, thus driving down engineering costs. Topology Optimization can help in determining a cost effective and efficient design which address existing structural design challenges.

scholarly journals Chip-Based Digital PCR Approach Provides A Sensitive and Cost-Effective Single-Day Screening Tool for Common Fetal Aneuploidies—A Proof of Concept Study

2019 ◽  
Vol 20 (21) ◽  
pp. 5486
Author(s):  
Anna Nykel ◽  
Marcin Kaszkowiak ◽  
Wojciech Fendler ◽  
Agnieszka Gach
Keyword(s):  
Clinical Utility ◽  
Screening Tool ◽  
Cost Effective ◽  
Digital Pcr ◽  
Trisomy 13 ◽  
Proof Of Concept ◽  
Rapid Tests ◽  
The Difference ◽  
Clinically Significant ◽  
Fetal Aneuploidies

In the prenatal period, the copy number aberrations of chromosomes 13, 18, 21, X and Y account for over 80% of the clinically significant chromosome abnormalities. Classical cytogenetic analysis is the gold standard in invasive prenatal diagnostics but the long test waiting time affects its clinical utility. Several molecular rapid tests have been developed and employed in clinical practice, however all have substantial drawbacks. The aim of the study was to design and evaluate an optimized tool for rapid molecular detection of fetal aneuploidies. We established a novel single-day method using a chip-based platform, the QuantStudio 3D Digital PCR system. In order to assess the clinical usefulness of our screening test, we analyzed 133 prenatal samples. The difference in distributions of euploid and aneuploid samples identified the ploidy of each of the target chromosomes with high precision. The distribution of the chromosome ratio for euploid and aneuploid samples showed a statistically significant result (p = 0.003 for trisomy 13, p = 0.001 for trisomies 18 and 21, Mann–Whitney U test). Our results suggest that this novel chip-based approach provides a tool for rapid, technically simple, cost-effective screening for common fetal aneuploidies.

scholarly journals Cost effective teaching and research tools for automotive dynamics

2017 ◽  
Vol 2 (1) ◽  
pp. 189-197
Author(s):  
Marius Bățăuș ◽  
Ionuț Stoica ◽  
Mircea Oprean
Keyword(s):  
Effective Teaching ◽  
Cost Effective ◽  
Hardware In The Loop ◽  
Proof Of Concept ◽  
Comparative Testing ◽  
Automotive Control ◽  
Teaching And Research ◽  
Alternative Technologies ◽  
The Core ◽  
Research Tools

Abstract The paper examines the problem of developing cost effective teaching and research tools for automotive dynamics. Different available solutions are presented and the need of human feedback is emphasized. Based on the demands from industry and academia (benchmarking, virtual prototyping, comparative testing of alternative technologies, development and tuning of the automotive control etc.) a solution is proposed. At the core of the proposed tool is a H2iL (humanand- hardware-in-the-loop) simulator based on an electric vehicle. An architecture is elaborated for the simulator and the proof of concept is done in three steps.

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