Investigations on thermodynamic processes of a novel pneumatic drive asymmetric Gifford-McMahon cycle cryorefrigerator

2021 ◽  
pp. 1-21
Author(s):  
Debashis Panda ◽  
Suraj Kumar Behera ◽  
Ashok Kumar Satapathy ◽  
Sunil K. Sarangi
Keyword(s):  
Numerical Model ◽  
Performance Parameters ◽  
Pneumatic Drive ◽  
Governing Equations ◽  
Expansion Process ◽  
Intake Process ◽  
The Impact ◽  
First Time ◽  
Thermodynamic Processes ◽  
Dead Centre

Abstract In this paper, a numerical and experimental investigation is conducted on a novel pneumatic-drive asymmetric Gifford-McMahon cycle cryorefrigerator for the first time. In the pneumatic-drive asymmetric Gifford-McMahon cycle cryorefrigerator, the duration of the assistance space exhaust process is kept higher than that of the assistance space intake process. Therefore, the displacer moves faster at the lower dead centre and slower at the upper dead centre inside the expander cylinder, which makes the duration of expansion process longer. The numerical model solves the governing equations of the refrigerant and dynamics of free-floating displacer iteratively to illustrate the refrigeration mechanisms. Additionally, the model computes the performance parameters of the cryorefrigerator, like refrigerating capacity, and specific refrigerating capacity. By adopting the numerical model, the impact of the loitering time on the thermodynamic processes is elaborated. It is perceived that, both refrigerating capacity and specific refrigerating capacity reduces with an increase in the loitering time. The experimental cooling characteristics are studied for different values of discharge to suction pressure ratios of helium compressor.

scholarly journals Evaluation of an Analytical Model for the Maximum Intensity of Tropical Cyclones

2009 ◽  
Vol 66 (10) ◽  
pp. 3042-3060 ◽  
Author(s):  
George H. Bryan ◽  
Richard Rotunno
Keyword(s):  
Numerical Model ◽  
Tropical Cyclones ◽  
Maximum Intensity ◽  
Model Output ◽  
Intensity Analysis ◽  
Governing Equations ◽  
Complete Model ◽  
External Conditions ◽  
Hydrostatic Balance ◽  
The Impact

Abstract Several studies have shown that the intensity of numerically simulated tropical cyclones can exceed (by 50%) a theoretical upper limit. To investigate the cause, this study evaluates the underlying components of Emanuel’s commonly cited analytic theory for potential intensity (herein referred to as E-PI). A review of the derivation of E-PI highlights three primary components: a dynamical component (gradient-wind and hydrostatic balance); a thermodynamical component (reversible or pseudoadiabatic thermodynamics, although the pseudoadiabatic assumption yields greater intensity); and a planetary boundary layer (PBL) closure (which relates the horizontal gradients of entropy and angular momentum at the top of the PBL to fluxes and stresses at the ocean surface). These three components are evaluated using output from an axisymmetric numerical model. The present analysis finds the thermodynamical component and the PBL closure to be sufficiently accurate for several different simulations. In contrast, the dynamical component is clearly violated. Although the balanced portion of the flow (υg, to which E-PI applies) appears to also exceed E-PI, it is shown that this difference is attributable to the method used to calculate υg from the model output. Evidence is shown that υg for a truly balanced cyclone does not exceed E-PI. To clearly quantify the impact of unbalanced flow, a more complete analytic model is presented. The model is not expressed in terms of external conditions and thus cannot be used to predict maximum intensity for a given environment; however, it does allow for evaluation of the relative contributions to maximum intensity from balanced and unbalanced (i.e., inertial) terms in the governing equations. Using numerical model output, this more complete model is shown to accurately model maximum intensity. Analysis against observations further confirms that the effects of unbalanced flow on maximum intensity are not always negligible. The contribution to intensity from unbalanced flow can become negligible in axisymmetric models as radial turbulence (i.e., viscosity) increases, and this explains why some previous studies concluded that E-PI was an accurate upper bound for their simulations. Conclusions of this study are also compared and contrasted to those from previous studies.

Relationship between big five personality model and abusive supervision

2019 ◽  
Vol 12 (2) ◽  
Author(s):  
Bibi Tahira ◽  
Naveed Saif ◽  
Muhammad Haroon ◽  
Sadaqat Ali
Keyword(s):  
Big Five ◽  
Abusive Supervision ◽  
State Universities ◽  
Big Five Personality ◽  
Big Five Model ◽  
The Impact ◽  
First Time ◽  
Supervisor Behavior ◽  
Moderating Role

The current study tries to understand the diverse nature of relationship between personality Big Five Model (PBFM) and student's perception of abusive supervision in higher education institutions of Khyber Pakhtoonkhwa Pakistan. Data was collected in dyads i.e. (supervisors were asked to rate their personality attributes while student were asked to rate the supervisor behavior) through adopted construct. For this purpose, data was collected from three government state universities and one Private Sector University. The focus was on MS/M.Phill and PhD student and their supervisors of the mentioned universities. After measuring normality and validity regression analysis was conducted to assess the impact of supervisor personality characteristics that leads to abusive supervision. Findings indicate interestingly that except agreeableness other four attributes of (PBFM) are play their role for abusive supervision. The results are novel in the nature as for the first time Neuroticism, openness to experience, extraversion and conscientiousness are held responsible for the abusive supervision. The study did not explore the demographic characteristics, and moderating role of organizational culture, justice and interpersonal deviances to understand the strength of relationship in more detail way. Keywords: Personality big five model, abusive supervision, HEIs

The Influence of TRIPS Compliant Patent Laws on Indian Pharmaceutical Industry

2014 ◽  
Vol 4 (1) ◽  
Author(s):  
Rupesh Rastogi ◽  
Virendra Kumar
Keyword(s):  
Pharmaceutical Industry ◽  
Patent Protection ◽  
Uruguay Round ◽  
Pharmaceutical Products ◽  
Trips Agreement ◽  
Patent Law ◽  
Patent Laws ◽  
The Impact ◽  
First Time ◽  
Indian Pharmaceutical Industry

The first legislation in India relating to patents was the Act VI of 1856. The Indian Patents and Design Act, 1911 (Act II of 1911) replaced all the previous Acts. The Act brought patent administration under the management of Controller of Patents for the first time. After Independence, it was felt that the Indian Patents & Designs Act, 1911 was not fulfilling its objective. Various comities were constituted to recommend, framing a patent law which can fulfill the requirement of Indian Industry and people. The Indian Patent Act of 1970 was enacted to achieve the above objectives. The major provisions of the act, provided for process, not the product patents in food, medicines, chemicals with a term of 14 years and 5-7 for chemicals and drugs. The Act enabled Indian citizens to access cheapest medicines in the world and paved a way for exponential growth of Indian Pharmaceutical Industry. TRIPS agreement, which is one of the important results of the Uruguay Round, mandated strong patent protection, especially for pharmaceutical products, thereby allowing the patenting of NCEs, compounds and processes. India is thereby required to meet the minimum standards under the TRIPS Agreement in relation to patents and the pharmaceutical industry. India’s patent legislation must now include provisions for availability of patents for both pharmaceutical products and processes inventions. The present paper examines the impact of change in Indian Patent law on Pharmaceutical Industry.

The impact of traditional plants and their secondary metabolites in the discovery of COVID-19 treatment

2020 ◽  
Vol 26 ◽  
Author(s):  
Shabana Bibi ◽  
Ayesha Sarfraz ◽  
Ghazala Mustafa ◽  
Zeeshan Ahmed ◽  
Muhammad Aurang Zeb ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
Test System ◽  
Chemical Information ◽  
System Type ◽  
The Family ◽  
Comprehensive Search ◽  
Coronavirus Infection ◽  
The Impact ◽  
First Time ◽  
Plant Sources

Background: Coronavirus Disease-2019 belongs to the family of viruses which cause a serious pneumonia along with fever, breathing issues and infection of lungs for the first time in China and later spread worldwide. Objective: Several studies and clinical trials have been conducted to identify potential drugs and vaccines for Coronavirus Disease-2019. The present study listed natural secondary metabolites identified from plant sources with antiviral properties and could be safer and tolerable treatment for Coronavirus Disease-2019. Methods: A comprehensive search on the reported studies was conducted using different search engine such as Google scholar, SciFinder, Sciencedirect, Medline PubMed, and Scopus for the collection of research articles based on plantderived secondary metabolites, herbal extracts, and traditional medicine for coronavirus infections. Results: Status of COVID-19 worldwide and information of important molecular targets involved in COVID-19 is described and through literature search, is highlighted that numerous plant species and their extracts possess antiviral properties and studied with respect to Coronavirus treatments. Chemical information, plant source, test system type with mechanism of action for each secondary metabolite is also mentioned in this review paper. Conclusion: The present review has listed plants that have presented antiviral potential in the previous coronavirus pandemics and their secondary metabolites which could be significant for the development of novel and a safer drug which could prevent and cure coronavirus infection worldwide.

Individual and Combined Assessment of Ser680Asn FSH Receptor and FSHβ -211 G>T Gene Polymorphisms in Ovarian Response in IVF/ICSI Program

2020 ◽  
Vol 21 ◽  
Author(s):  
Elli Anagnostou ◽  
Alexia Kafkoutsou ◽  
Despina Mavrogianni ◽  
Ekaterini Domali ◽  
Evangelia Dimitroulia ◽  
...  
Keyword(s):  
Gene Polymorphism ◽  
Gene Polymorphisms ◽  
Ovarian Response ◽  
Greek Population ◽  
Control Group ◽  
Genotype Distribution ◽  
Β Subunit ◽  
Molecular Genetic Study ◽  
The Impact ◽  
First Time

Background: Molecular biology tools, such as the detection of single nucleotide polymorphisms (SNPs), have been considered to assist to the management of the ovarian stimulation protocols. Purpose: The aim of this study was to evaluate the impact of two polymorphisms, the Asn680Ser polymorphism of the FSHR gene, and the FSH β subunit (FSHβ) gene polymorphism -211 G>T, in a Greek population of women undergoing IVF/ICSI program in our center. In addition, a control group of fertile women was studied, to verify whether there are differences in the genotype distribution between fertile and infertile population for both polymorphisms, as the FSHβ gene polymorphism -211 G>T is studied for the first time in the Greek population. Results : The FSH β-211 G>T polymorphism, studied for the first time in the Greek infertile population, appears to be quite rare. When studying the two polymorphisms separately, statistically significant differences were obtained that concerned the LH levels. Discussion: According to the combination analysis of the two polymorphisms by the number of alleles, women with 2-3 polymorphic alleles needed more days of stimulation, but there were no differences in pregnancy rates. Conclusion: This molecular genetic study helps to elucidate whether the polygenic combination of the Asn680Ser and FSH β subunit -211 G>T gene polymorphisms is of additive value in the prediction of ovarian response to exogenous gonadotropins.

Reconstituting the International, 1918–1923

2017 ◽  
Author(s):  
Talbot C. Imlay
Keyword(s):  
Seismic Events ◽  
Great War ◽  
Bolshevik Revolution ◽  
Meaning And Purpose ◽  
Post War ◽  
The Impact ◽  
First Time ◽  
The Great War ◽  
Do So ◽  
Lengthy Process

This chapter examines the post-war efforts of European socialists to reconstitute the Socialist International. Initial efforts to cooperate culminated in an international socialist conference in Berne in February 1919 at which socialists from the two wartime camps met for the first time. In the end, however, it would take four years to reconstitute the International with the creation of the Labour and Socialist International (LSI) in 1923. That it took so long to do so is a testimony to the impact of the Great War and to the Bolshevik revolution. Together, these two seismic events compelled socialists to reconsider the meaning and purpose of socialism. The search for answers sparked prolonged debates between and within the major parties, profoundly reconfiguring the pre-war world of European socialism. One prominent stake in this lengthy process, moreover, was the nature of socialist internationalism—both its content and its functioning.

scholarly journals Autism Tsunami: the Impact of Rising Prevalence on the Societal Cost of Autism in the United States

2021 ◽  
Author(s):  
Mark Blaxill ◽  
Toby Rogers ◽  
Cynthia Nevison
Keyword(s):  
Forecast Model ◽  
The United States ◽  
Population Projections ◽  
Base Case ◽  
Prevention Strategies ◽  
Total Base ◽  
Cost Categories ◽  
The Cost ◽  
The Impact ◽  
First Time

AbstractThe cost of ASD in the U.S. is estimated using a forecast model that for the first time accounts for the true historical increase in ASD. Model inputs include ASD prevalence, census population projections, six cost categories, ten age brackets, inflation projections, and three future prevalence scenarios. Future ASD costs increase dramatically: total base-case costs of $223 (175–271) billion/year are estimated in 2020; $589 billion/year in 2030, $1.36 trillion/year in 2040, and $5.54 (4.29–6.78) trillion/year by 2060, with substantial potential savings through ASD prevention. Rising prevalence, the shift from child to adult-dominated costs, the transfer of costs from parents onto government, and the soaring total costs raise pressing policy questions and demand an urgent focus on prevention strategies.

scholarly journals A Model for the Thermal Behaviour of an Offshore Cable Installed in a J-Tube

Proceedings ◽  
2020 ◽  
Vol 58 (1) ◽  
pp. 31
Author(s):  
Jeremy Arancio ◽  
Ahmed Ould El Moctar ◽  
Minh Nguyen Tuan ◽  
Faradj Tayat ◽  
Jean-Philippe Roques
Keyword(s):  
Sensitivity Analysis ◽  
Numerical Model ◽  
Thermal Behaviour ◽  
Energy Production ◽  
Power Transmission ◽  
Temperature Fields ◽  
Sobol Indices ◽  
Lumped Element ◽  
Thermal Phenomena ◽  
The Impact

In the race for energy production, supplier companies are concerned by the thermal rating of offshore cables installed in a J-tube, not covered by IEC 60287 standards, and are now looking for solutions to optimize this type of system. This paper presents a numerical model capable of calculating temperature fields of a power transmission cable installed in a J-tube, based on the lumped element method. This model is validated against the existing literature. A sensitivity analysis performed using Sobol indices is then presented in order to understand the impact of the different parameters involved in the heating of the cable. This analysis provides an understanding of the thermal phenomena in the J-tube and paves the way for potential technical and economic solutions to increase the ampacity of offshore cables installed in a J-tube.

scholarly journals The Impact of Ambient Atmospheric Mineral-Dust Particles on the Calcification of Lungs

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 125
Author(s):  
Mariola Jabłońska ◽  
Janusz Janeczek ◽  
Beata Smieja-Król
Keyword(s):  
Mineral Dust ◽  
Smoking Habit ◽  
Lower Lobe ◽  
Ambient Air ◽  
Dust Particles ◽  
Masking Effect ◽  
Amorphous Calcium Carbonate ◽  
Calcium Salts ◽  
The Impact ◽  
First Time

For the first time, it is shown that inhaled ambient air-dust particles settled in the human lower respiratory tract induce lung calcification. Chemical and mineral compositions of pulmonary calcium precipitates in the lung right lower-lobe (RLL) tissues of 12 individuals who lived in the Upper Silesia conurbation in Poland and who had died from causes not related to a lung disorder were determined by transmission and scanning electron microscopy. Whereas calcium salts in lungs are usually reported as phosphates, calcium salts precipitated in the studied RLL tissue were almost exclusively carbonates, specifically Mg-calcite and calcite. These constituted 37% of the 1652 mineral particles examined. Mg-calcite predominated in the submicrometer size range, with a MgCO3 content up to 50 mol %. Magnesium plays a significant role in lung mineralization, a fact so far overlooked. The calcium phosphate (hydroxyapatite) content in the studied RLL tissue was negligible. The predominance of carbonates is explained by the increased CO2 fugacity in the RLL. Carbonates enveloped inhaled mineral-dust particles, including uranium-bearing oxides, quartz, aluminosilicates, and metal sulfides. Three possible pathways for the carbonates precipitation on the dust particles are postulated: (1) precipitation of amorphous calcium carbonate (ACC), followed by its transformation to calcite; (2) precipitation of Mg-ACC, followed by its transformation to Mg-calcite; (3) precipitation of Mg-free ACC, causing a localized relative enrichment in Mg ions and subsequent heterogeneous nucleation and crystal growth of Mg-calcite. The actual number of inhaled dust particles may be significantly greater than was observed because of the masking effect of the carbonate coatings. There is no simple correlation between smoking habit and lung calcification.

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