scholarly journals UJI EKSPERIMENTAL MESIN PENDINGIN BERPENDINGIN AIR DENGAN MENGGUNAKAN REFRIGERAN R22 DAN REFRIGERAN R407C

POROS ◽  
2014 ◽  
Vol 12 (2) ◽  
pp. 165
Author(s):  
Terry Gunawan ◽  
Harto Tanujaya ◽  
Asrul Aziz
Keyword(s):  
Global Warming ◽  
Environmental Problems ◽  
Ozone Layer ◽  
Test Results ◽  
Refrigeration System ◽  
Human Needs ◽  
Processing Data ◽  
Refrigeration Capacity ◽  
Compressor Power ◽  
Test Result

Abstract: The human needs of refrigeration system have created a tool that called a refrigerator. Refrigerator/cooling machine have a component which have a very important role in the refrigeration system that is refrigerant. Refrigerant that still widely used for cooling machine until now is the refrigerant R22. Using R22 refrigerant can cause environmental problems such as damage to the ozone layer and global warming. Therefore, it needs a substitution refrigerant which is more friendly for environment which one of them is R407C refrigerant. In this study, using a cooling machine with water- cooled condenser and the flowrate that use is 20 L/h, 40 L/h, 80 L/h and 120 L/h. The variables that measured in this study is temperature (T1, T2, T3, T4, T10, T11), pressure (P1, P2, P3, P4), and ampere. This study aims to get the test results using refrigerants R22 and R407C. The processing data of the test result include refrigeration capacity, compressor power and COP. The results obtained have that cooling machine which use R22 refrigerants have a better COP than using R407C refrigerant. This is happen because the power needed by the compressor to compress R407C refrigerant to flow in the system is greater than using R22 refrigerant. 

Current and Future Trends of Refrigerants Development

2016 ◽  
pp. 474-524
Author(s):  
M. V. Duarte ◽  
L. C. Pires ◽  
P. D. Silva ◽  
P. D. Gaspar
Keyword(s):  
Global Warming ◽  
Ethyl Ether ◽  
Large Scale ◽  
Environmental Issues ◽  
Ozone Layer ◽  
Environmental Concerns ◽  
Historical Evolution ◽  
Future Trends ◽  
Refrigeration System

In this chapter is addressed the thematic of refrigerants: its historical evolution; properties; legislation applied in the area and future trends. The first refrigerant being marketed on a large scale was ethyl ether (R610), in 1834. Since then, the evolution of the utilized refrigerants was stimulated, initially due to constructive issues in the refrigeration system and later to environmental issues. This evolution may be divided into four generations: 1st use of any fluid that worked; 2nd safety and durability of the equipment; 3rd ozone layer protection and 4th increase of global warming concerns. During the process of evolution many refrigerants were tested to understanding of their properties. Currently, environmental concerns are taken as guide in the search for new refrigerants. The most promising refrigerants to be used in future are the HFEs, HFOs and HFCs with low-GWP, natural refrigerants and blends between (HCs/HFCs and HFCs/HFOs) refrigerants.

Current and Future Trends of Refrigerants Development

2017 ◽  
pp. 1900-1951
Author(s):  
M. V. Duarte ◽  
L. C. Pires ◽  
P. D. Silva ◽  
P. D. Gaspar
Keyword(s):  
Global Warming ◽  
Ethyl Ether ◽  
Large Scale ◽  
Environmental Issues ◽  
Ozone Layer ◽  
Environmental Concerns ◽  
Historical Evolution ◽  
Future Trends ◽  
Refrigeration System

In this chapter is addressed the thematic of refrigerants: its historical evolution; properties; legislation applied in the area and future trends. The first refrigerant being marketed on a large scale was ethyl ether (R610), in 1834. Since then, the evolution of the utilized refrigerants was stimulated, initially due to constructive issues in the refrigeration system and later to environmental issues. This evolution may be divided into four generations: 1st use of any fluid that worked; 2nd safety and durability of the equipment; 3rd ozone layer protection and 4th increase of global warming concerns. During the process of evolution many refrigerants were tested to understanding of their properties. Currently, environmental concerns are taken as guide in the search for new refrigerants. The most promising refrigerants to be used in future are the HFEs, HFOs and HFCs with low-GWP, natural refrigerants and blends between (HCs/HFCs and HFCs/HFOs) refrigerants.

Current and Future Trends of Refrigerants Development

2015 ◽  
pp. 207-259
Author(s):  
M. V. Duarte ◽  
L. C. Pires ◽  
P. D. Silva ◽  
P. D. Gaspar
Keyword(s):  
Global Warming ◽  
Ethyl Ether ◽  
Large Scale ◽  
Environmental Issues ◽  
Ozone Layer ◽  
Environmental Concerns ◽  
Historical Evolution ◽  
Future Trends ◽  
Refrigeration System

In this chapter is addressed the thematic of refrigerants: its historical evolution; properties; legislation applied in the area and future trends. The first refrigerant being marketed on a large scale was ethyl ether (R610), in 1834. Since then, the evolution of the utilized refrigerants was stimulated, initially due to constructive issues in the refrigeration system and later to environmental issues. This evolution may be divided into four generations: 1st use of any fluid that worked; 2nd safety and durability of the equipment; 3rd ozone layer protection and 4th increase of global warming concerns. During the process of evolution many refrigerants were tested to understanding of their properties. Currently, environmental concerns are taken as guide in the search for new refrigerants. The most promising refrigerants to be used in future are the HFEs, HFOs and HFCs with low-GWP, natural refrigerants and blends between (HCs/HFCs and HFCs/HFOs) refrigerants.

scholarly journals UJI EKSPERIMENTAL MESIN PENDINGIN BERPENDINGIN UDARA, DENGAN MENGGUNAKAN REFRIGERAN R22 DAN REFRIGERAN R407C

POROS ◽  
2014 ◽  
Vol 12 (2) ◽  
pp. 129
Author(s):  
Kevin Sanjaya ◽  
I Made Kartika ◽  
Harto Tanujaya
Keyword(s):  
Data Processing ◽  
Test Data ◽  
Flow Rate ◽  
Experimental Methods ◽  
Ozone Layer ◽  
Coefficient Of Performance ◽  
Ozone Layer Depletion ◽  
Refrigeration Capacity ◽  
Compressor Power

Abstract: Refrigerant R22 can cause ozone layer depletion so that required refrigerant substitute for R22. Refrigerant R407C is one of the refrigerant substitute for R22. Research of refrigerant in the cooling engine with air-cooled condenser is done by experimental methods. This research was conducted using refrigerants R22 and refrigerant R407C with a flow rate of 20 L /h, 40 L/h, 80 L/h and 120 L/h. Test data processing include the calculation of refrigeration capacity, compressor power and COP values. COP or Coefficient Of Performance shows the efficiency of the refrigerant. The best COP values are in the refrigerant flow rate of 40 L/h, with R22 COP value of 5.818 and R407C COP value of 4.875. 

CURRENT ENVIRONMENTAL PROBLEMS AND SUGGESTIONS

2015 ◽  
Vol 3 (9SE) ◽  
pp. 1-3
Author(s):  
Sudha Shakya
Keyword(s):  
Global Warming ◽  
Population Growth ◽  
Environmental Problems ◽  
Ozone Layer ◽  
Sea Pollution ◽  
Research Article ◽  
Pollution Damage

Today, every person, life and flora is getting life from the environment itself, but the situation of the environment has become such that it has become very difficult to handle. The present research article is presented with the objective of solving the problems of the environment and how to solve them. Today environmental problems are causing problems like population growth, pollution, global warming, sea pollution, damage to ozone layer, waste decomposition, reduction in biodiversity etc., which has become very important to solve and solve them. आज पर्यावरण से ही हर व्यक्ति जीवजंतु एंव वनस्पतियों को जीवन मिल रहा है, परंतु पर्यावरण की स्थिति ऐसी हो गई है कि जिसे संभालना बहुत मुश्किल हो गया है। प्रस्तुत शोध आलेख वर्तमान में पर्यावरण की कौन-कौन सी समस्याएं हैं और उसका निराकरण एवं समाधान कैसे किया जाये के उद्देश्य से प्रस्तुत है। आज पर्यावरणीय समस्याओं में जनसंख्या वृद्धि, प्रदूषण, वैश्विक ताप, समुद्र प्रदूषण, ओजान परत का क्षतिग्रस्त होना, अपशिष्ट विघटन, जैव विविधता में कमी आदि समस्याएं उत्पन्न हो रही हैं, जिसका समाधान एवं निराकरण अति आवश्यक हो गया है।

Item Context and /s/ Phone Articulation Test Results

1972 ◽  
Vol 15 (4) ◽  
pp. 852-860 ◽  
Author(s):  
Zoe Zehel ◽  
Ralph L. Shelton ◽  
William B. Arndt ◽  
Virginia Wright ◽  
Mary Elbert
Keyword(s):  
Test Score ◽  
Sound Production ◽  
Broad Context ◽  
Test Results ◽  
Production Task ◽  
Test Result

Fourteen children who misarticulated some phones of the /s/ phoneme were tape recorded articulating several lists of items involving /s/. The lists included the Mc-Donald Deep Test for /s/, three lists similar to McDonald’s but altered in broad context, and an /s/ sound production task. Scores from lists were correlated, compared for differences in means, or both. Item sets determined by immediate context were also compared for differences between means. All lists were found to be significantly correlated. The comparison of means indicated that both broad and immediate context were related to test result. The estimated “omega square” statistic was used to evaluate the percentage of test score variance attributable to context.

scholarly journals New HFC/HFO Blends as Refrigerants for the Vapor-Compression Refrigeration System (VCRS)

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 946
Author(s):  
Bartosz Gil ◽  
Anna Szczepanowska ◽  
Sabina Rosiek
Keyword(s):  
Global Warming ◽  
Global Warming Potential ◽  
Mass Fraction ◽  
Vapor Compression ◽  
Refrigeration System ◽  
Operational Parameters ◽  
Vapor Compression Refrigeration ◽  
Low Global Warming Potential ◽  
Triangular Design

In this work, which is related to the current European Parliament Regulation on restrictions affecting refrigeration, four new three-component refrigerants have been proposed; all were created using low Global Warming Potential(GWP) synthetic and natural refrigerants. The considered mixtures consisted of R32, R41, R161, R152a, R1234ze (E), R1234yf, R1243zf, and RE170. These mixtures were theoretically tested with a 10% step in mass fraction using a triangular design. The analysis covered two theoretical cooling cycles at evaporating temperatures of 0 and −30 °C, and a 30 °C constant condensing temperature. The final stage of the work was the determination of the best mixture compositions by thermodynamic and operational parameters. R1234yf–R152a–RE170 with a weight share of 0.1/0.5/0.4 was determined to be the optimal mixture for potentially replacing the existing refrigerants.

scholarly journals Influenza colloidal gold method and blood routine tests combination for rapid diagnosis of influenza: a decision tree-based analysis

2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Xiaoguang Li ◽  
Jing Chen ◽  
Fei Lin ◽  
Wei Wang ◽  
Jie Xu ◽  
...  
Keyword(s):  
Decision Tree ◽  
Predictive Value ◽  
Colloidal Gold ◽  
Influenza A ◽  
Clinical Manifestations ◽  
Rapid Test ◽  
Test Results ◽  
Tree Model ◽  
Routine Blood ◽  
Test Result

AbstractRapid influenza diagnosis can facilitate targeted treatment and reduce antibiotic misuse. However, diagnosis efficacy remains unclear. This study examined the efficacy of a colloidal gold rapid test for rapid influenza diagnosis. Clinical characteristics of 520 patients with influenza-like illness presenting at a fever outpatient clinic during two influenza seasons (2017–2018; 2018–2019) were evaluated. The clinical manifestations and results of routine blood, colloidal gold, and nucleic acid tests were used to construct a decision tree with three layers, nine nodes, and five terminal nodes. The combined positive predictive value of a positive colloidal gold test result and monocyte level within 10.95–12.55% was 88.2%. The combined negative predictive value of a negative colloidal gold test result and white blood cell count > 9.075 × 109/L was 84.9%. The decision-tree model showed the satisfactory accuracy of an early influenza diagnosis based on colloidal gold and routine blood test results.

Patient recommendations for content and design for electronic return of genetic test results: An interview study among patients who accessed their genetic test results online (Preprint)

2021 ◽  
Author(s):  
Diane M Korngiebel ◽  
Kathleen McGlone West
Keyword(s):  
Patient Preferences ◽  
Genetic Test ◽  
Smartphone Application ◽  
Patient Portal ◽  
Genetic Test Result ◽  
Test Results ◽  
User Centered Design ◽  
Detailed Report ◽  
Genetic Test Results ◽  
Test Result

BACKGROUND Genetic test results will be increasingly made available electronically as more patient-facing tools are developed; however, little research has been done that collects patient preferences for content and design before creating results templates. OBJECTIVE This study identifies patient preferences for electronic return of genetic test results, including what considerations should be prioritized for content and design. METHODS Following User-Centered Design methods, 59 interviews were conducted using semi-structured protocols. The interviews explored content and design issues for patient portal results return for patients who received electronic results for specific types of genetic tests (pharmacogenomic, hereditary blood disorders, and positive and negative risk results for heritable cancers) or who had electronically received any type of genetic test result as well as a non-genetic test result. RESULTS In general, a majority of participants felt that there always needed to be some clinician involvement in electronic results return and that electronic coversheets with simple summaries would be helpful for facilitating that. Coversheet summaries could accompany, but not replace, the more detailed report. Participants had specific suggestions for those results summaries, such as only reporting the information that was most important for patients to understand, including next steps, and to do so using clear language free of medical jargon. Electronic results return should also include explicit encouragement for patients to contact providers with questions. Finally, many participants preferred to manage their care using their smartphones, particularly in instances where they needed to access health information on the go. CONCLUSIONS Participants recommended that a patient-friendly front section accompany the more detailed report and made suggestions for organization, content, and wording. Many used their smartphones regularly to access test results, therefore, health systems and patient portal software vendors should accommodate smartphone application design and web portal design concomitantly when developing results return platforms. CLINICALTRIAL N/A

Death and COVID-19 Anxiety in Home-Quarantined Individuals Aged 65 and Over During the Pandemic

2021 ◽  
pp. 003022282110598
Author(s):  
Hümeyra Aslaner ◽  
Betül Özen ◽  
Zeliha K. Erten ◽  
Mebrure Beyza Gökçek
Keyword(s):  
Polymerase Chain Reaction ◽  
Death Anxiety ◽  
Short Form ◽  
Anxiety Score ◽  
Test Results ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Polymerase Chain ◽  
Test Result ◽  
Pcr Test

Urgent measures were taken for those at the age of 65 and over who were at the risk group all over the world due to the COVID-19 pandemic. It is known that many individuals at the age of 65 and over have experienced anxiety due to the uncertainties. This study aimed to determine the anxiety and death anxiety in individuals aged 65 and over who were isolation at home due to being diagnosed with COVID-19 or being in contact during the pandemic process. The study is descriptive and cross-sectional. It was performed with 656 home-quarantined individuals aged between 65–80 years with positive or negative real-time polymerase chain reaction (RT-PCR) test result. A form including questions about the death anxiety and the Coronavirus Anxiety Scale Short Form prepared by the researchers were administered to the individuals by phone call. Of the participants, 49.5% were male. Median COVID-19 anxiety score was 4 (0–18). Anxiety scores of the male and female participants were similar. Participants with negative polymerase chain reaction (PCR) results and those with death anxiety had higher COVID anxiety scores. Death anxiety has increased by 1.661 times in male gender, 1.983 times in RT-PCR positivity and 0.146 times in the presence of symptoms. Individuals with positive COVID-19 test results or those aged 65 and over who had death anxiety and negative COVID-19 test result but who were in home-isolation due to being a contact had higher anxiety score. For this reason, those with death anxiety can be supported in line with their religious beliefs to reduce anxiety. Those with negative PCR test results in quarantine can be adequately informed about the COVID-19.

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