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Journal articles on the topic 'R507a'

Author: Grafiati

Published: 4 June 2021

Last updated: 20 June 2025

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Selan, Rima Nindia, and Matheus Magnus Dwinanto. "Studi Kinerja dan Konsumsi Energi Air Blast Freezer Menggunakan Refrigeran Hidrofluorokarbon dan Hidrokarbon." Jurnal Dinamika Vokasional Teknik Mesin 6, no. 1 (2021): 26–34. http://dx.doi.org/10.21831/dinamika.v6i1.36728.

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Penggunaan refrigeran hidrokarbon yang lebih ramah lingkungan dibandingkan dengan hidrofluorokarbon telah menjadi tuntutan dan isu sentral pada masa yang akan datang baik itu di refrigerator rumah tangga maupun di refrigerator industri seperti air blast freezer. Hal ini disebabkan refrigeran hidrokarbon tidak memiliki potensi penipisan ozon ODP dan potensi pemanasan global GWP minimal. Makalah ini menyajikan studi kinerja teoritis penggunaan R290 dan R600a sebagai pengganti R404A dan R507A. Perangkat lunak CoolPack digunakan untuk mensimulasikan kinerja dan konsumsi energi sistem pada beberapa variasi temperatur evaporasi dengan temperatur kondensasi dipertahankan konstan. Hasilnya menunjukkan bahwa pada temperatur evaporator minimum, kinerja sistem yang menggunakan R290 dan R600a rata-rata lebih tinggi ±14% dibandingkan dengan R404A dan R507A. R290 memiliki karakteristik yang lebih dekat pada R404A dan R507A sehingga lebih sesuai menggantikan kedua refrigeran tersebut dibandingkan dengan R600a. Namun, ini adalah analisis teoritis sistem yang dapat mengarah pada kinerja yang lebih tinggi daripada kondisi normal. Namun, ini adalah analisis teoritis sistem yang dapat mengarah pada kinerja yang lebih tinggi daripada kondisi normal. The use of hydrocarbon refrigerants that are more environmentally friendly than hydrofluorocarbons has become a demand. It will be a central issue in the future, both in household refrigerators and in industrial refrigerators such as air blast freezers. That is because hydrocarbon refrigerants have zero ozone depletion potential (ODP) and minimal global warming potential (GWP). This paper presents a theoretical performance study of R290 and R600a as substitutes for R404A and R507A refrigerants. CoolPack software is used to simulate the system's performance and energy consumption at several variations of the evaporation temperature, with the condensation temperature being kept constant. The results show that at the minimum evaporator temperature, the system performance using R290 and R600a is ±14% higher on average compared to R404A and R507A. R290 has closer characteristics to R404A and R507A, so it is more suitable to replace the two refrigerants compared to R600a. However, this is a theoretical analysis of the system that can lead to higher performance than normal conditions.

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Servianus, Yohanes Viva. "PERBANDINGAN KINERJA TEORITIS AIR BLAST FREEZER MENGGUNAKAN REFRIGERAN HIDROFLUOROKARBON DAN HIDROKARBON." Machine : Jurnal Teknik Mesin 7, no. 2 (2022): 1–7. http://dx.doi.org/10.33019/jm.v7i2.1833.

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Air blast freezer telah digunakan sebagai cara pembekuan cepat di unit pengolahan ikan sebelum dibekukan untuk waktu yang lama di dalam cold storage. Untuk itu penggunaan refrigeran hidrokarbon yang lebih ramah lingkungan telah menjadi tuntutan dan isu sentral pada masa yang akan datang. Makalah ini menyajikan studi kinerja teoritis penggunaan R290 dan R600a sebagai pengganti R404A dan R507A. Kinerja teoritis sistem didasarkan pada variasi temperatur evaporasi menggunakan perangkat lunak CoolPack dengan temperatur kondensasi dipertahankan konstan. Besaran-besaran penting yang dianalisis adalah laju aliran massa, rasio tekanan, temperatur keluar kompresor, pelepasan kalor, konsumsi daya, koefisien kinerja, efisiensi refrigerasi, dan konsumsi energi. Hasilnya menunjukkan bahwa pada temperatur evaporator minimum, kinerja sistem yang menggunakan R290 dan R600a rata-rata lebih tinggi ±14% dibandingkan dengan R404A dan R507A. R290 memiliki karakteristik yang lebih dekat pada R404A dan R507A sehingga lebih sesuai menggantikan kedua refrigeran tersebut dibandingkan dengan R600a. Namun, ini adalah analisis teoritis sistem yang dapat mengarah pada kinerja yang lebih tinggi daripada kondisi normal.

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Shikov, Sergei, Wenman Wu, and Peter N. Walsh. "Structural Determinants for Heparin Binding in Human Coagulation Factor XI." Blood 110, no. 11 (2007): 2705. http://dx.doi.org/10.1182/blood.v110.11.2705.2705.

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Abstract Previous studies from our laboratory and others have demonstrated that zymogen factor XI (FXI) binds to heparin with moderate (KD ∼110 nM) affinity via residues (K252, K253 and K255) located in the Apple 3 (A3) domain. In contrast, the enzyme, FXIa, was shown to bind to heparin (Biochemistry40: 7569–7580, 2001) with significantly higher affinity (KD ∼9 nM by SPR and ∼1.5 nM by ELISA) via residues (K529, R530 and R532) within the catalytic domain (CD). This interaction potentiates by ∼10-fold the inhibition of FXIa by protease nexin-2. Also, polyanions heparin and dextran sulfate inhibit the catalytic activity of the enzyme factor XIa. The present study was designed to determine the relative contributions of positively charged residues as well as the dimeric structure of FXI to heparin binding. Mutational analysis of full-length FXI expressed in HEK293 cells was based on the following criteria: Conservation of the positively charged residues in FXI among various species; Surface exposure of the residues based on the X-ray crystal structure of FXI (Papagrigoriou E, McEwan P, Walsh PN, Emsley J,Nat. Struct. & Mol. Biol. 2006; 13:557–558); and comparison with human plasma prekallikrein (PK), which does not bind heparin. Two positively charged residues Arg507 (147, chymotrypsin numbering) and Arg532 (173) are conserved in FXI genes of all species for which sequences are available. In human PK, Arg507 is replaced by lysine, while Arg532 is replaced by a neutral glutamine. We have expressed and purified wtFXI, R507A, R532A as well as monomeric C321S/K331A and C321A/I290A. While wtFXI, R507A and R532A demonstrated normal activity in APTT assays; monomeric FXI mutants retained 60-70% activity. The R532A and R507A mutants demonstrated ∼75% decrease in total number of heparin binding sites based on the solid phase ELISA assay using 5F7 monoclonal antibody. Also, the apparent dissociation constants for R507 (11 nM) and R532A (22 nM) were 7 and 11-fold increased respectively compared with 1.6 nM for the wtFXI. We also characterized monomeric FXI C321S/K331A and C321A/I290A proteins for their ability to bind to heparin compared with wtFXI using surface plasmon resonance (SPR). Surprisingly, the monomeric FXI mutants, C321S/K331A and C321A/I290A, which had no mutations in any heparin-binding regions, displayed major defects in binding to heparin by SPR. Although kinetic analysis is challenging due to complex binding kinetics, while Rmax is about 10-fold lower, the off-rate for the binding of the monomeric FXI mutants is drastically increased when compared to that of wtFXI. These results suggest the possibility that the unique dimeric structure of FXI is required for cooperative binding to heparin. Thus, the dimeric structure of FXI and basic residues R507 and R532 in the catalytic domain of factor XI are both necessary for high-affinity heparin binding.

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Kuczyński, Waldemar, Marcin Kruzel, and Katarzyna Chliszcz. "Regression Model of Dynamic Pulse Instabilities during Condensation of Zeotropic and Azeotropic Refrigerant Mixtures R404A, R448A and R507A in Minichannels." Energies 15, no. 5 (2022): 1789. http://dx.doi.org/10.3390/en15051789.

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This paper presents experimental research and mathematical modeling data concerning the impact of unit dynamic instabilities on the phase-transition condensation processes of the zeotropic mixtures R404A and R448A and azeotropic R507A refrigerants in pipe minichannels. The R507 refrigerant is currently used as a temporary substitute for R404A, whereas R448A is a sustainable prospective substitute for R404A. The study presents experimental testing data for the condensation processes of these refrigerants in pipe minichannels and a proposal for the use of dimensional analysis, including the Π-Buckingham theorem, to determine the regression relationship explaining the propagation of unit dynamic instabilities. Based on the experimental studies performed, regression computational models were developed and showed satisfactory agreement in the range of 20% to 25%. They give the possibility to identify, in a utilitarian, way the speed of propagation of temperature and pressure instabilities during the liquefaction of refrigerants. The study was carried out on pipe minichannels with an internal diameter of di = 3.3, 2.3, 1.92, 1.44 and 1.40 mm.

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Mancuhan, Ebru. "Comparative evaluation of a two-stage refrigeration system with flash intercooling using different refrigerants." Thermal Science 24, no. 2 Part A (2020): 815–30. http://dx.doi.org/10.2298/tsci180921011m.

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The aim of this study is to investigate the effect of low global warming potential refrigerants on the optimum intermediate pressure (POPT,int) and performance (COP) values of a refrigeration system with flash intercooling. For realize, the optimum operating parameters of system were determined in low temperature applications through a theoretical analysis according to the different refrigerants (R290, R404A, R407C, R507A, and R22). The theoretical modelling of system is done by optimizing the intermediate pressure at given evaporation (TE) and condensation (TC) temperatures for selected refrigerants. After optimization, the maximized values of COP and Second law efficiency are computed from the predicted values of POPT,int . The linear regression method is then used to derive three correlations of POPT,int , maximum values of COP and Second law efficiency according to TE and TC. Hence, the POPT,int values maximizing the system performance are found from various TE and TC values for each refrigerant. Due to calculations, increasing TE and TC cause the increase in POPT,int in low temperature applications. The R507A system has the highest POPT,int values and R22 system has the lowest POPT?int values. Although R22 system has slightly more efficient than R290 system, it is being phased out world?wide because of the risk of ozone depletion potential and global warming potential considerations. Therefore, it is important to evaluate the R22 replacement options. The R290 was discovered to have better performance than the R404A, R407C and R507A systems in terms of COPmax (1.81), global warming potential (11), and ozone depletion potential (0) when TE and TC are -35?C and 40?C.

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HABIB, O. Khairul, Bidvut B. SAHA, Ibrahim I. ELSHARKAWY, Anutosh CHAKRABORTY, and Shigeru KOYAMA. "B104 HENRY'S LAW COEFFICIENTS FOR ADSORPTION OF R507A ON ACTIVATED CARBON." Proceedings of the National Symposium on Power and Energy Systems 2008.13 (2008): 63–66. http://dx.doi.org/10.1299/jsmepes.2008.13.63.

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Habib, Khairul. "Performance Study of Waste Heat Driven Pressurized Adsorption Chiller." Applied Mechanics and Materials 315 (April 2013): 380–84. http://dx.doi.org/10.4028/www.scientific.net/amm.315.380.

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This article presents a transient modeling and performance of a waste heat driven pressurized adsorption chiller. This innovative adsorption chiller employs pitch based activated carbon of type Maxsorb III as adsorbent and R507A as refrigerant as adsorbent-refrigerant pair. This chiller utilizes low-grade heat source to power the cycle. A parametric study has been presented where the effects of adsorption/desorption cycle time, switching time and regeneration temperature on the performance are reported in terms of cooling capacity and coefficient of performance (COP). Results indicate that the adsorption chiller is feasible even when low-temperature heat source is available.

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Arora, Akhilesh, and S. C. Kaushik. "Theoretical analysis of a vapour compression refrigeration system with R502, R404A and R507A." International Journal of Refrigeration 31, no. 6 (2008): 998–1005. http://dx.doi.org/10.1016/j.ijrefrig.2007.12.015.

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Habib, Khairul, Bidyut B. Saha, Kazi A. Rahman, Anutosh Chakraborty, Shigeru Koyama, and Kim Choon Ng. "Experimental study on adsorption kinetics of activated carbon/R134a and activated carbon/R507A pairs." International Journal of Refrigeration 33, no. 4 (2010): 706–13. http://dx.doi.org/10.1016/j.ijrefrig.2010.01.006.

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Stojanović, Milan, and Uroš Milovančević. "Sintetičke alternative za rashladno sredstvo R404A." KGH – Klimatizacija, grejanje, hlađenje 46, no. 1 (2017): 87. http://dx.doi.org/10.24094/kghc.017.46.1.87.

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Od uvođenja rashladnih sredstava HCFC baziranih na R22 traže se rešenja koja će biti trajnijeg karaktera. Prva zamena za HCFC – R22 bazirana na HFC R404A u Evropi je prevaziđena uvođenjem propisa EN 517/2014 (sa važnošću od 1.1.2015) kao naslednika prethodne direktive EN 862/2006. Servisna zabrana rada sa R404A i R507A od 2020. godine u Evropi će otežati serviserima potragu za budućim zamenama i obeležavanjima za šta se treba spremati već danas. Alternative koje su danas predložene za R404A (GWP 3922) jesu: R407A (2107), R407C (1774), R407F(1825), R410A (2088), R442A (1888), R449A (1397), HFO – R452A (2140) i radi poređenja R32 (675). U radu će biti odabrane najperspektivnije alternative i navedene uporedne termodinamičke karakteristike na koje inženjeri koji projektuju sisteme i serviseri u eksploataciji treba da obrate pažnju.

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Ermakov, Andrey, Richat Salakhov, and Renat Khismatullin. "Improving the performance of the vapor compression cycle using an internal heat exchanger." E3S Web of Conferences 459 (2023): 07003. http://dx.doi.org/10.1051/e3sconf/202345907003.

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The main additional consumer of electrical energy in an electric bus is the climate system, which can consume up to 30% of electrical energy. This problem is especially relevant in Russia at low ambient temperatures. The optimal solution is to switch the vapor compression unit to heat pump mode. However, at low temperatures, its efficiency decreases and performance is insufficient. One way to improve efficiency is to use an internal heat exchanger. In this paper, we studied the effect of an internal heat exchanger on the performance of a vapor compression cycle using R290, R410a and R507a refrigerants. The influence of geometry on the performance of the internal heat exchanger is determined. The use of an internal heat exchanger makes it possible to increase coefficient of performance by 10-13%.

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Chakraborty, Anutosh, Bidyut Baran Saha, Kim Choon Ng, Ibrahim I. El-Sharkawy, and Shigeru Koyama. "Thermodynamic Property Surfaces for Adsorption of R507A, R134a, andn-Butane on Pitch-Based Carbonaceous Porous Materials." Heat Transfer Engineering 31, no. 11 (2010): 917–23. http://dx.doi.org/10.1080/01457631003604152.

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Llopis, R., E. Torrella, R. Cabello, and D. Sánchez. "Performance evaluation of R404A and R507A refrigerant mixtures in an experimental double-stage vapour compression plant." Applied Energy 87, no. 5 (2010): 1546–53. http://dx.doi.org/10.1016/j.apenergy.2009.10.020.

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bin Ismail, Azhar, Li Ang, Kyaw Thu, and Kim Choon Ng. "Low Temperature Waste Heat Driven Refrigeration Cycle." Applied Mechanics and Materials 819 (January 2016): 241–44. http://dx.doi.org/10.4028/www.scientific.net/amm.819.241.

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This work explores the utilization of alternative refrigerants to the conventional silica gel + water adsorption pair for the adsorption chiller cycle. Water as the working fluid in the cycle limits the cooling temperatures to above 0°C due to its triple point. The activated carbon Maxsorb III is thus considered as the adsorbent due to its high micro-porous characteristics which lead to higher uptake values. The isotherms of this adsorbent with natural refrigerant Propane, n-butane as well as refrigerants HFC-134a, R507a and R-32 are fitted to the Dubinin-Astakhov equation and the parameters tabulated. With these isotherms, the performances of these pairs with respect to their Specific Cooling Effects (SCE) are compared for assorted cooling temperature, ambient temperature and waste temperature requirements. It was found that the natural refrigerant propane exhibits the most favorable operational conditions when the required cooling temperature is below 0°C. A mathematical model is thus developed to predict the cycle of the propane cycle and is found to show a good fit to the experimental results.

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Lucchini, A., I. M. Carraretto, L. P. M. Colombo, D. Mazzeo, P. G. Pittoni, and G. Lipori. "Convective condensation of R449a inside a smooth tube." Journal of Physics: Conference Series 2685, no. 1 (2024): 012062. http://dx.doi.org/10.1088/1742-6596/2685/1/012062.

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Abstract The HVAC sector has started the phase-out of refrigerants characterized by high values of global warming potential and atmospheric lifetime. Drop-in replacement requires that the new, environmentally safe fluids also show comparable heat transfer performances. This work addresses R449a, a low GWP zeotropic mixture (components: R32, R125, R1234yf, R134a, mass fractions: 24.3%, 24.7%, 25.3%, 25.7%, respectively), suitable to replace both R404A and R507A. Experiments were carried out on condensation in horizontal smooth tubes (outer diameter: 9.52 mm, thickness: 0.3 mm). The range of operating conditions meets the standard for HVAC devices (operating pressure: 14.46 bar, bubble temperature: 30°C, temperature glide: approximately 5 K refrigerant mass flux ranging from 136 to 202 kg m−2 s−1, quality change -0.8 and -0.2, mean quality ranging from 0.2 to 0.8). The test section is the inner pipe in a tube-in-tube counter-flow heat exchanger, where the refrigerant is cooled by a demineralized water stream in the annulus. Both the pressure drop and the heat transfer coefficient were measured across a length of 1.3 m and 1.1 m, respectively.

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Siva Reddy, V., N. L. Panwar, and S. C. Kaushik. "Exergetic analysis of a vapour compression refrigeration system with R134a, R143a, R152a, R404A, R407C, R410A, R502 and R507A." Clean Technologies and Environmental Policy 14, no. 1 (2011): 47–53. http://dx.doi.org/10.1007/s10098-011-0374-0.

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Misra, R. K. "Thermodynamic Performance Evaluation of Multi-Evaporators single Compressor and single Expansion Valve and Liquid Vapour Heat Exchanger in Vapour Compression Refrigeration systems using Thirteen Eco-friendly Refrigerants for Reducing Global Warming and Oz." International Journal of Advance Research and Innovation 2, no. 2 (2014): 139–49. http://dx.doi.org/10.51976/ijari.221421.

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The methods for improving first law and second law efficiency have been considered in this paper by using liquid vapour heat exchanger is investigated in this paper. Detailed energy and exergy analysis of multi-evaporators at different temperatures with single compressor and single expansion valve using liquid vapour heat exchanger vapour compression refrigeration systems have been done in terms of performance parameter for R507a, R125, R134a, R290, R600, R600a, R1234ze, R1234yf, R410a, R407c, R707, R404a and R152a refrigerants. The numerical computations have been carried out for both systems. It was observed that first law and second law efficiency improved by 20% using liquid vapour heat exchanger in the vapour compression refrigeration systems. It was also observed that performance of both systems using R717 is higher but R600 and R152a nearly matching same values under the accuracy of 5% can be used in the above system .But difficulties using R152a, R600, R290 and R600a have flammable problems therefore safety measures are required using these refrigerants. Therefore R134a refrigerant is recommended for practical and commercial applications although it has slightly less thermal performance than R152a which is not widely used refrigerant for domestic and industrial applications

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Misra, R. S. "Methods for Improving Thermodynamic Performance of Vapour Compression Refrigeration Systems using Thirteen Ecofriendly Refrigerants in Primary Circuit and Tio2 Nano Particles Mixed with R718 used in Secondary Evaporator Circuit for Reducing Global Warming." International Journal of Advance Research and Innovation 2, no. 4 (2014): 113–17. http://dx.doi.org/10.51976/ijari.241416.

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The methods for improving first law and second law efficiency have been considered in this paper by using water as secondary coolent in evaporator with nano particles such als Al2O3 and TiO2 mixed R718 refrigerant is investigated in this paper. Detailed energy and exergy analysis of multi-evaporators at different temperatures in the vapour compression refrigeration systems have been done in terms of performance parameter for R507a, R125, R134a, R290, R600, R600a, R410a, R407c, R404a and R152a refrigerants. The numerical computations have been carried out for both systems. The use of nano particles improves the first law and second law performance significantly. The best performance is found using R152a and worst performance is observed using R410a. Due to flammable nature of R290, R600, R600a and R152a The results were compared by using water in secondary circuit with nano refrigerants and without nano particles used and it was found that use of nano particles improves thermal performances. The first law performance improvement in terms of COP and second law performance in terms of exergetic efficiency (rational efficiency) using TiO2 is better than using Al2O3 with R718 refrigerant in the secondary evaporator circuit.

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Mishra, R. S. "Thermodynamic Performance Evaluation of Multi-Evaporators Single Compressor and Single Expansion Valve and Liquid Vapour Heat Exchanger in Vapour Compression Refrigeration Systems using Thirteen Ecofriendly Refrigerants for Reducing Global Warming and Ozo." International Journal of Advance Research and Innovation 1, no. 3 (2013): 107–17. http://dx.doi.org/10.51976/ijari.131315.

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Mishra, R. S. "Methods for Improving Thermodynamic Energy and Exergy Performance of Vapour Compression Refrigeration Systems Using Thirteen Ecofriendly Refrigerants in Primary Circuit and TIO2 Nano Particles Mixed with R718 Used in Secondary Evaporator Circuit for Reduc." International Journal of Advance Research and Innovation 4, no. 2 (2016): 85–90. http://dx.doi.org/10.51976/ijari.421613.

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The methods for improving energy and exergetic efficiency have been considered in this paper by using water as secondary coolent in evaporator with nano particles ofAl2O3 and TiO2 mixed R718 refrigerant is investigated in this paper. Detailed energy and exergy analysis of multi-evaporators at different temperatures in the vapour compression refrigeration systems have been done in terms of performance parameter for R507a, R125, R134a, R290, R600, R600a, R410a, R407c, R404a and R152a refrigerants. The numerical computations have been carried out for both systems. The use of nano particles improves the energy and exergy performance significantly. The best thermodynamic performance is found using R152a and worst performance is observed using R410a. Due to flammable nature of R290, R600, R600a and R152a , the R134a is recommended for domestic applications. The results were compared by using water in secondary circuit with nano refrigerants and without nano particles used and it was found that use of nano particles improves thermal performances significantly The energy performance improvement in terms of COP and exergetic performance in terms of exergetic efficiency (rational efficiency) using TiO2 is better than using Al2O3 with R718 refrigerant in the secondary evaporator circuit.

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Mishra, R. S. "Methods for Improving Thermodynamic Energy and Exergy Performance of Vapor Compression Refrigeration Systems Using Thirteen Eco-Friendly Refrigerants in Primary Circuit and Tio2 Nano Particles Mixed with R718 Used In Secondary Evaporator Circuit for Reduc." International Journal of Advance Research and Innovation 4, no. 1 (2016): 212–18. http://dx.doi.org/10.51976/ijari.411631.

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The methods for improving energy and exergetic efficiency have been considered in this paper by using water as secondary coolant in evaporator with nano particles of Al2O3 and TiO2 mixed R718 refrigerant is investigated in this paper. Detailed energy and exergy analysis of multi-evaporators at different temperatures in the vapor compression refrigeration systems have been done in terms of performance parameter for R507a, R125, R134a, R290, R600, R600a, R410a, R407c, R404a and R152a refrigerants. The numerical computations have been carried out for both systems. The use of nano particles improves the energy and exergy performance significantly. The best thermodynamic performance is found using R152a and worst performance is observed using R410a. Due to flammable nature of R290, R600, R600a and R152a , the R134a is recommended for domestic applications. The results were compared by using water in secondary circuit with nano refrigerants and without nano-particles used and it was found that use of nano-particles improves thermal performances significantly. The energy performance improvement in terms of COP and exergetic performance in terms of exergetic efficiency (rational efficiency) using TiO2 is better than using Al2O3 with R718 refrigerant in the secondary evaporator circuit.

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Butrymowicz, Dariusz, Kamil Śmierciew, Jarosław Karwacki, Aleksandra Borsukiewicz, and Jerzy Gagan. "Experimental Investigations of Flow Boiling Heat Transfer under Near-Critical Pressure for Selected Working Fluids." Sustainability 14, no. 21 (2022): 14029. http://dx.doi.org/10.3390/su142114029.

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This paper deals with experimental investigations of flow boiling in tubular ducts of selected refrigerants—R134a, R507A, and R600a—under near-critical pressures. Near-critical boiling is characterised by low specific enthalpy of evaporation. The positive effect of this feature is the fact that only a small amount of heat consumed by Organic Rankine Cycles is at a constant temperature. This allows a lower terminal temperature of the heating fluid and more effective utilisation of heat sources, especially of low-grade heat sources. The experimental investigations covered a heat flux density of 0.4 to 10 kW/m2 and a mass velocity of 60 to 200 kg/(m2·s). The results of the experimental data were compared to the modified heat transfer correlation of Gungor and Winterton, which provices the best fit for the obtained experimental data. The maximum heat transfer coefficient occurred at the two-phase quality—approximately 0.4 for all the tested fluids under high pressure conditions—which may be thought of as a characteristic feature of the boiling process under near-critical conditions. A modified Gungor–Winterton correlation improves prediction accuracy, especially under the lowest (up to 3 kW/m2) and highest (over 7 kW/m2) heat flux densities for all the tested fluids.

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Köse, Ali, Parisa Heidarnejad, and Berker Özün FENNİ. "Design of a Cold Storage with R507A Refrigerant for the Preservation of Twenty-Five Tons of Apples in the Ankara Province." International Journal of New Findings in Engineering, Science and Technology 1, no. 1 (2023): 1–14. http://dx.doi.org/10.61150/ijonfest.2023010101.

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In the absence of proper humidity and temperature conditions, undried fresh foods will experience physiological and biological deterioration, resulting in mass loss and the development of mold. Thanks to this rationale, humanity has endeavored to keep food products from deteriorating. This can be observed through the use of cold rooms constructed by the Ancient Romans using clay and the cooling chambers known as "Yakhchāl" developed by the Persians. The advancement of refrigeration technology has persisted since the era of ancient civilizations. The advent of refrigeration cycles has significantly streamlined the implementation of containment technology. The presence of these systems in residential settings can be attributed to the development of the vapor compression refrigeration cycle and the compact nature of this technology, which enables convenient freezing or cooling of products for storage purposes. Vapor compression refrigeration cycles are still widely employed in various applications, such as office and automotive air conditioning systems, refrigerators, and industrial cold rooms. This study aims to develop an industrial cold room design tailored explicitly for storing and transporting apples, a perishable agricultural commodity. The primary objective is to ensure that the apples are maintained in optimal humidity and temperature conditions, thereby preventing any degradation, even when handling large quantities in Ankara.

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Shabir, Faizan, Muhammad Sultan, Yasir Niaz, et al. "Steady-State Investigation of Carbon-Based Adsorbent–Adsorbate Pairs for Heat Transformation Application." Sustainability 12, no. 17 (2020): 7040. http://dx.doi.org/10.3390/su12177040.

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In this study, the ideal adsorption cycle behavior of eight activated carbon and refrigerant pairs is evaluated. The selected pairs are KOH6-PR/ethanol, WPT-AC/ethanol, Maxsorb-III/methanol, Maxsorb-III/CO2, Maxsorb-III/n-butane, Maxsorb-III/R-134a, SAC-2/R32 and Maxsorb-III/R507a. The following cooling performance parameters are evaluated for all pairs: specific cooling energy (SCE), concentration difference (ΔW) and coefficient of performance (COP) of ideal adsorption cooling and refrigeration cycles. The evaporator temperatures for the applications of adsorption cooling and refrigeration are selected as 7 and −5 °C, respectively. It is found that the Maxsorb-III/methanol pair has shown the highest specific cooling energy and coefficient of performance in a wide range of desorption temperatures; i.e., for the adsorption cooling cycle it has SCE and COP of 639.83 kJ/kg and 0.803, respectively, with desorption temperatures of 80 °C. The KOH6-PR/ethanol and the WPT-AC/ethanol pairs also give good performances comparable to that of the Maxsorb-III/methanol pair. However, the SAC-2/R32 pair possesses a higher concentration difference than the Maxsorb-III/methanol, KOH6-PR/ethanol and WPT-AC/ethanol pairs but shows a lower performance. This is due to the lower isosteric heat of adsorption of SAC-2/R32 compared to these pairs. It is found that Maxsorb-III/methanol, KOH6-PR/ethanol and WPT-AC/ethanol are the most promising pairs for application in designing adsorption cooling and refrigeration systems.

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Chopra, Kapil, V. Sahni, and R. S. Mishra. "Energetic and Exergetic Based Comparison Multiple Evaporators with Compound Compression and Flash Intercooler with Individual or Multiple Throttle Valves." International Journal of Advance Research and Innovation 1, no. 1 (2013): 67–76. http://dx.doi.org/10.51976/ijari.111309.

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The utility of second law analysis on vapour compression refrigeration systems is well defined because it gives the idea for improvements in efficiency due to modifications in existing design in terms of reducing exergy destructions in the components. Due to effect of global warming and ozone depletion the comparison and impact of environmental friendly refrigerants (R507a, R410a, R290, R600, R600a, R1234yf, R404a, R125, R717, R152a and R407C) on multiple evaporators at different temperature with compound compression and flash intercooler with individual and multiple throttle valves is important for calculating first law and second law performance on the basis of energetic and exergetic approach. Comparison was done for multiple evaporators with compound compression and flash intercooler with individual throttle valves (system-1) and multiple evaporators with compound compression and flash intercooler with multiple throttle valves (system-2) in terms of coefficient of performance, rational efficiency and total system defect. It was observed that for all considered refrigerants second law first law efficiency of system-1 is lower than sytem-2 conversely system defect of system-1 is higher than system-2.In terms of energetic efficiency, rational efficiency and system defect for both systemsR407C shows minimum performance and performances of R600, R152a and R717 better with comparison of other selected refrigerants for system-1 and system-2. But R600 is highly inflammable and R717 is toxic in nature and restricted to limited applications, so R152a is suggested for both systems.

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Ermakov, Andrey, Rishat Salakhov, Ildar Hafizov, and Arslan Zakirov. "Methods for increasing the efficiency of climate control systems for electric buses." E3S Web of Conferences 531 (2024): 02011. http://dx.doi.org/10.1051/e3sconf/202453102011.

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Increasing the range of an electric bus on a single battery charge is an important task facing electric bus developers. The auxiliary system that consumes the largest amount of electricity is the air conditioning system. This paper examines the main methods for increasing the efficiency of a climate control system and evaluates them using numerical methods using a verified one-dimensional mathematical model. The following methods were chosen to improve efficiency: the most suitable refrigerants, the use of an internal heat exchanger of a vapor compression unit, the recovery of heat from the air removed from the interior electric bus in the evaporator of a vapor compression unit, and the use of heat from electrical equipment in the climate control system. The greatest efficiency in cooling and heating modes is shown by the use of refrigerants R404a, R410a and R507a in the vapor compression unit. The use of an internal heat exchanger in a vapor compression unit allows an increase in coefficient of performance by 11%. The combined use of cabin heat in the evaporator of the vapor compression unit and the internal heat exchanger allows the coefficient of performance to be increased by 27%. Using the heat of electrical equipment allows you to increase the coefficient of performance in heat pump mode by 20%. The most promising is the combined use of the above methods to reduce the cost of air conditioning in the cold season.

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Thanh Nien Le. "Phân Tích Nhiệt Động Của Một Số Loại Môi Chất Lạnh Dùng Trong Tủ Lạnh Và Kho Lạnh Công Nghiệp". Journal of Technical Education Science 19, SI01 (2024): 20–28. http://dx.doi.org/10.54644/jte.2024.1252.

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Phân tích exergy là công cụ mạnh mẽ trong thiết kế, tối ưu hóa và đánh giá hiệu suất của hệ thống năng lượng. Trong bài báo này, tác giả phân tích nhiệt động của các hệ thống lạnh một cấp nén môi chất R22, R717, R404A, R507A, R1234yf, R134a, R600a bằng các thông số: Nhiệt độ đầu đẩy máy nén T2 [K], năng suất lạnh riêng thể tích qv [kJ/m3] , hệ số làm lạnh COP, hiệu suất exergy COPex, độ hoàn thiện chu trình η[%], tổn thất exergy Exd,total [kW] tại nhiệt độ ngưng tụ Tk = 315[K], nhiệt độ bay hơi T0 = 268[K], 265[K], 258[K], 253[K], 248[K], 243[K], 238[K]. Qua đó, tác giả nhận thấy rằng trong các hệ thống lạnh nhiệt độ âm có công suất nhỏ như tủ lạnh, tủ kem thì môi chất R600a vì cho kết quả hệ số làm lạnh COP, hiệu suất exergy, năng suất lạnh thể tích riêng, độ hoàn thiện chu trình lớn hơn R134a và cao nhất trong các loại môi chất lạnh được sự dụng hiện nay. Trong các hệ thống kho lạnh công nghiệp thì môi chất R22 có nhiệt độ cuối tầm nén thấp hơn NH3 dẫn đến có thể không bắt buộc có thêm hệ thống làm mát đầu đẩy máy nén, hệ số làm lạnh COP gần giống nhau, tổn thất exergy NH3 quá lớn dù hiệu suất exergy gần giống nhau. Nếu xét về mặt ảnh hưởng tới môi trường thì môi chất lạnh NH3 vẫn là ưu tiên lựa chọn so với R22.

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Cukras, C. A., I. Jeliazkova, and C. G. Nichols. "The Role of NH2-terminal Positive Charges in the Activity of Inward Rectifier KATP Channels." Journal of General Physiology 120, no. 3 (2002): 437–46. http://dx.doi.org/10.1085/jgp.20028621.

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Approximately half of the NH2 terminus of inward rectifier (Kir) channels can be deleted without significant change in channel function, but activity is lost when more than ∼30 conserved residues before the first membrane spanning domain (M1) are removed. Systematic replacement of the positive charges in the NH2 terminus of Kir6.2 with alanine reveals several residues that affect channel function when neutralized. Certain mutations (R4A, R5A, R16A, R27A, R39A, K47A, R50A, R54A, K67A) change open probability, whereas an overlapping set of mutants (R16A, R27A, K39A, K47A, R50A, R54A, K67A) change ATP sensitivity. Further analysis of the latter set differentiates mutations that alter ATP sensitivity as a consequence of altered open state stability (R16A, K39A, K67A) from those that may affect ATP binding directly (K47A, R50A, R54A). The data help to define the structural determinants of Kir channel function, and suggest possible structural motifs within the NH2 terminus, as well as the relationship of the NH2 terminus with the extended cytoplasmic COOH terminus of the channel.

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Baginsky, A. V., and A. S. Shipitsyna. "Thermal conductivity of liquid R507 refrigerant." Thermophysics and Aeromechanics 15, no. 2 (2008): 291–95. http://dx.doi.org/10.1134/s0869864308020121.

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Hommais, Antoine, Julie Rayes, Anne Houllier, et al. "Molecular characterization of four ADAMTS13 mutations responsible for congenital thrombotic thrombocytopenic purpura (Upshaw-Schulman syndrome)." Thrombosis and Haemostasis 98, no. 09 (2007): 593–99. http://dx.doi.org/10.1160/th07-01-0059.

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SummaryADAMTS13 mutations S203P, R268P, R507Q and A596V were previously identified in French patients with hereditary thrombotic thrombocytopenic purpura (TTP) (Upshaw-Schulman syndrome). Mutated recombinant (r) ADAMTS13 were transiently expressed in COS-7 cells and characterized in comparison with wild-type (WT) rADAMTS13.ADAMTS13 antigen was qualitatively and quantitatively estimated by electrophoretic analysis and ELISA. Enzymatic activity was qualitatively and quantitatively estimated using GST-VWF73,FRETS-VWF73 fragments and full-length rVWF-WT as substrates. The four mutants and rADAMTS13-WT were present within the cells. Secretion level of rADAMTS13-WT reached 1,200 ng/ml. The four mutations strongly altered the secretion and biological activity of rADAMTS13. The percentage secretion was 21, 38 and 17% for rADAMTS13-S203P, -R268P and -A596V compared with rADAMTS13- WT. rADAMTS13-R507Q concentration was under the detection limit of the assay. In the four cases, no enzymatic activity was detected. After concentration, we confirmed that mutations S203P and R268P totally abolished the proteolytic activity of ADAMTS13. Due to the very low protease concentration, activity of rADAMTS13-R507Q was below the threshold of the assays. rADAMTS13-A596V had no proteolytic activity towards the full-length rVWF-WT whereas it exhibited a decreased specific activity of about 30% of that of rADAMTS13- WT towards FRETS-VWF73 fragment. Binding study of mutated rADAMTS13-S203P, -R268P and -A596V showed that the three mutations strongly decreased the interaction of ADAMTS13 with VWF. In conclusion, the four mutations, which led to a secretion defect, a loss of enzymatic activity and a decreased binding to the substrate, are responsible for the hereditary TTP in patients.

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Deuse, T., X. Hua, M. Stubbendorff, et al. "Inhaled Immunosuppression Using the Novel JAK1/3 Inhibitor R507." Journal of Heart and Lung Transplantation 32, no. 4 (2013): S82—S83. http://dx.doi.org/10.1016/j.healun.2013.01.210.

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Marsi, M., R. Belkhou, C. Grupp, et al. "Transient charge carrier distribution at UV-photoexcitedSiO2/Siinterfaces." Physical Review B 61, no. 8 (2000): R5070—R5073. http://dx.doi.org/10.1103/physrevb.61.r5070.

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Yamanaka, Toshiro, and Shozo Ino. "Surface electron standing waves and adatom heights onSi(111)−3×3−(Ga,In,Sn)surfaces." Physical Review B 61, no. 8 (2000): R5074—R5077. http://dx.doi.org/10.1103/physrevb.61.r5074.

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Yokoyama, Takashi, and Kunio Takayanagi. "Anomalous flipping motions of buckled dimers on the Si(001) surface at 5 K." Physical Review B 61, no. 8 (2000): R5078—R5081. http://dx.doi.org/10.1103/physrevb.61.r5078.

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Rahul, V. Ikhar, and Farkade H.S. "Evaluation of Vapour Compression Refrigeration System Using R407C and R507." International Journal of Engineering Research and Advanced Technology (IJERAT) 3, no. 4 (2017): 1–9. https://doi.org/10.5281/zenodo.439656.

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The existing refrigerant requirements are, system performance should not be compromised, refrigerant and lubrication interaction should be as required, it should be energy efficient, environment friendly etc. After Montreal protocol, use of refrigerants like CFC and HCFC banned because of high ozone depleting potential (ODP). So there is need to find out a refrigerant which is environment friendly, such as HFC refrigerants as working fluids in refrigeration and air conditioning systems and which can be used long term substitute for existing refrigerants. The most important qualification for refrigerants is low ozone depleting potential (ODP). HFC refrigerants have suitable specifications such as non-flammability, stability, and similar vapour pressure to the refrigerant CFCs and HCFCs and zero ozone depleting potential (ODP) . They are used in many applications with safety of the leakage from the system also with these refrigerants it was found that, there was no need to change in the design of the refrigeration system. So we can look forward to HFC refrigerants. R407C and R507 are HFC refrigerants which are under study.

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Avsec, Jurij, Milan Marcic, Alfred Leipertz, and Andreas P. Froba. "Velocity of Sound of Binary Mixture R507 and Ternary Mixture R404A." Journal of Thermophysics and Heat Transfer 17, no. 3 (2003): 334–39. http://dx.doi.org/10.2514/2.6790.

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Döring, R., H. Buchwald, and J. Hellmann. "Results of experimental and theoretical studies of the azeeotropic refrigerant R507." International Journal of Refrigeration 20, no. 2 (1997): 78–84. http://dx.doi.org/10.1016/s0140-7007(96)00071-0.

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Sakaguchi, T., M. Takahashi, and G. A. Bray. "Lateral hypothalamus and sympathetic firing rate." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 255, no. 3 (1988): R507—R512. http://dx.doi.org/10.1152/ajpregu.1988.255.3.r507.

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Measurements of sympathetic firing rate have been made after the acute microinjection of glucose or insulin into the lateral hypothalamic area as well as after ablation of this area with locally injected gold thioglucose. Injection of glucose into the lateral hypothalamus (LH) produced a small but significant and dose-dependent reduction in the firing rate of efferent sympathetic nerves to interscapular brown adipose tissue. Injection of insulin into the same region produced a very short-lived increase in efferent sympathetic firing rate. Bilateral lesions in the lateral hypothalamus produced by microinjection and gold thioglucose lowered body weight more than sham injections into the LH of control animals. There was an increase in basal sympathetic firing rate at 3, 9, and 24 h after LH lesions. There was also an increase in firing rate at 1 and 3 days, but by 7 days firing rate had returned to control levels. The data support the hypothesis that LH lesions enhance sympathetic activity but show only very limited modulation by glucose or insulin.

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Lipke, D. W., K. D. Meisheri, and K. R. Olson. "Generation of vasoactive substances in trout and rat plasma by trypsin and kallikrein." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 258, no. 2 (1990): R507—R514. http://dx.doi.org/10.1152/ajpregu.1990.258.2.r507.

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In the preceding study we demonstrated kallikrein-like enzymatic activity in trout tissues and showed that kallikrein incubated with trout plasma (T60K) produces a vasopressor substance(s). The present study further examines the effects of T60K in fish and mammals in vitro and in vivo. T60K produced a dose-dependent pressor response in both trout and rats, whereas kallikrein-activated rat plasma (R60K) was pressor in trout and depressor in rats. Captopril did not affect the response of rats to T60K or R60K. Phenoxybenzamine attenuated the T60K response in trout but not in rats, thus T60K effects in trout are partially mediated through catecholamines. Blockade of angiotensin II (ANG II) receptors in rats with [Sar1,Ala8]-ANG II abolished the pressor effects of T60K. T60K produced dose-dependent contractions in isolated trout and rabbit arteries; ANG II was ineffective in trout arteries. T60K-contracted trout arteries were relaxed by atrial natriuretic peptide and forskolin, whereas diltiazem and sodium nitroprusside were without effect. [Sar1,Ala8]ANG II inhibited T60K-induced contractions of rabbit arteries and relaxed rings previously contracted with T60K. The active component of T60K has a molecular weight less than 10,000, is heat stable, and is inactivated by peptidases. It is immunologically different than mammalian angiotensins but binds to and displaces radiolabeled ANG II from ANG II receptors. These results suggest that kallikrein forms a vasoactive substance(s) in trout plasma that is neither bradykinin nor ANG II but is similar to the latter in its pharmacological effects.

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Akins, V. F., and S. L. Bealer. "Brain histamine regulates pressor responses to peripheral hyperosmolality." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 259, no. 3 (1990): R507—R513. http://dx.doi.org/10.1152/ajpregu.1990.259.3.r507.

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The role of brain histamine (HA) in the pressor response to peripheral hyperosmolality was investigated in the conscious Sprague-Dawley rat. Increased mean arterial pressure was observed during a 30-min intravenous infusion of hypertonic saline (HTS; 10 microliters.100 g body wt-1 x min-1) in vehicle-treated controls (20.1 +/- 3.8 mmHg) and in animals centrally pretreated with the specific H2-antagonist, cimetidine (15.0 +/- 3.7 mmHg). However, this pressor response was abolished in a dose-dependent manner after intracerebroventricular injection of the H1 antagonist promethazine. In other experiments, brain tissue microdissected from the supraoptic nucleus (SON), paraventricular nucleus (PVN), and posterior hypothalamic region showed significantly lower levels of total tissue HA after 60 min of intravenous HTS infusion compared with tissue taken from control animals receiving an isotonic infusion. Microdialysis in the region of the PVN or SON before and during HTS infusion showed increased extracellular concentrations of HA in the SON (24.4 +/- 10.9%) during infusion. No change in extracellular HA concentration was seen in the PVN during HTS infusion. These results support the conclusion that endogenous brain HA is involved in the pressor response to peripheral hyperosmolality.

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Ingemarsson, Anders, and Göran Fäldt. "Dark sphere with a bright interior: A nucleus viewed by intermediate energy alpha particles." Physical Review C 48, no. 2 (1993): R507—R508. http://dx.doi.org/10.1103/physrevc.48.r507.

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Dulloo, A. G., and D. S. Miller. "Prevention of genetic fa/fa obesity with an ephedrine-methylxanthines thermogenic mixture." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 252, no. 3 (1987): R507—R513. http://dx.doi.org/10.1152/ajpregu.1987.252.3.r507.

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A thermogenic mixture containing ephedrine and methylxanthines was administered to 8-wk-old genetically obese fa/fa rats (O-E/Mx group) for a period of 15 wk. Their energy balance and the final body composition were compared with an untreated ad libitum-fed (O-AL) group, as well as to other fa/fa obese animals that were either pair fed to lean controls (O-PF group), or that were food restricted to such an extent they maintained a similar body weight to that of lean animals (O-WF group). Energy intake was elevated above lean or O-PF levels by approximately 27 and 10% in the O-AL and O-E/Mx groups, respectively, but lower by 18% in the O-WF group. Energy expenditure, compared with the lean values, was 10% higher in both the O-AL and O-E/Mx groups, but reduced by 13 and 30% in the O-PF and O-WF groups, respectively. The gain in body energy and the efficiency of energy deposition remained elevated above the lean values by 2.3- to 3.5-fold in the O-AL, O-PF, and O-WF groups but were reduced to lean levels in the O-E/Mx groups. These studies indicate that, unlike food restriction, the ephedrine-methylxanthine mixture prevents or arrests the development of the obesity in the fa/fa mutant by normalizing their energetic efficiency to that of the lean.

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Brossard, N., J. C. Combes, O. Guillery, J. C. Foissac, and M. F.R.eysz. "R507 Transport interhospitalier medicalise des menaces d'accouchement premature: resultats d'une enquete nationale." Annales Françaises d'Anesthésie et de Réanimation 17, no. 8 (1998): 1064. http://dx.doi.org/10.1016/s0750-7658(98)80624-2.

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Bhaijee, Feriyl, Brenda Jordan, Dominique J. Pepper, Rodney Leacock, and William A. Rock. "Venous Thrombosis with Both Heterozygous Factor V Leiden (R507Q) and Factor II (G20210A) Mutations." American Society for Clinical Laboratory Science 25, no. 4 (2012): 199–205. http://dx.doi.org/10.29074/ascls.25.4.199.

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Knapp, Anna M., Jon E. Ramsey, Shu-Xia Wang, Arthur R. Strauch та Robert J. Kelm. "Structure-Function Analysis of Mouse Purβ II". Journal of Biological Chemistry 282, № 49 (2007): 35899–909. http://dx.doi.org/10.1074/jbc.m706617200.

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Previous studies from our laboratories have implicated two members of the Pur family of single-stranded DNA/RNA-binding proteins, Purα and Purβ, in transcriptional repression of the smooth muscle α-actin gene in vascular cell types. Although Purα and Purβ share substantial sequence homology and nucleic acid binding properties, genomic promoter and cis-element occupancy studies reported herein suggest that Purβ is the dominant factor in gene regulation. To dissect the molecular basis of Purβ repressor activity, site-directed mutagenesis was used to map amino acids critical to the physical and functional interaction of Purβ with the smooth muscle α-actin promoter. Of all the various acidic, basic, and aromatic residues studied, mutation of positionally conserved arginines in the class I or class II repeat modules significantly attenuated Purβ repressor activity in transfected vascular smooth muscle cells and fibroblasts. DNA binding and protein-protein interaction assays were conducted with purified recombinant Purβ and selected mutants to reveal the physical basis for loss-of-function. Mutants R57E, R57E/R96E, and R57A/R96A each exhibited reduced single-stranded DNA binding affinity for an essential promoter element and diminished interaction with corepressor YB-1/MSY1. Structural analyses of the R57A/R96A and R57E/R96E double mutants in comparison to the wild-type Purβ homodimer revealed aberrant self-association into higher order oligomeric complexes, which correlated with decreased α-helical content and defective DNA and protein binding in vitro. These findings point to a previously unrecognized structural role for certain core arginine residues in forming a conformationally stable Purβ protein capable of physical interactions necessary for smooth muscle α-actin gene repression.

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Eastman, Scott W., and Maxine L. Linial. "Identification of a Conserved Residue of Foamy Virus Gag Required for Intracellular Capsid Assembly." Journal of Virology 75, no. 15 (2001): 6857–64. http://dx.doi.org/10.1128/jvi.75.15.6857-6864.2001.

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ABSTRACT In contrast to all retroviruses but similar to the hepatitis B virus, foamy viruses (FV) require expression of the envelope protein for budding of intracellular capsids from the cell, suggesting a specific interaction between the Gag and Env proteins. Capsid assembly occurs in the cytoplasm of infected cells in a manner similar to that for the B- and D-type viruses; however, in contrast to these retroviruses, FV Gag lacks an N-terminal myristylation signal and capsids are not targeted to the plasma membrane (PM). We have found that mutation of an absolutely conserved arginine (Arg) residue at position 50 to alanine (R50A) of the simian foamy virus SFV cpz(hu) inhibits proper capsid assembly and abolishes viral budding even in the presence of the envelope (Env) glycoproteins. Particle assembly and extracellular release of virus can be restored to this mutant with the addition of an N-terminal Src myristylation signal (Myr-R50A), presumably by providing an alternate site for assembly to occur at the PM. In addition, the strict requirement of Env expression for capsid budding can be bypassed by addition of a PM-targeting signal to Gag. These results suggest that intracellular capsid assembly may be mediated by a signal akin to the cytoplasmic targeting and retention signal CTRS found in Mason-Pfizer monkey virus and that FV Gag has the inherent ability to assemble capsids at multiple sites like conventional retroviruses. The necessity of Env expression for particle egress is most probably due to the lack of a membrane-targeting signal within FV Gag to direct capsids to the PM for release and indicates that Gag-Env interactions are essential to drive particle budding.

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de Brito, Filipe, Anelia Gurova, Carlos Nieto de Castro, and Umesh Mardolcar. "Dielectric constant and dipole moment of hydrofluorocarbon refrigerant mixtures R404A, R407C, and R507." High Temperatures-High Pressures 32, no. 6 (2000): 631–51. http://dx.doi.org/10.1068/htwu504.

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Kuczynski, Waldemar, Tadeusz Bohdal, Josua P. Meyer, and Aleksander Denis. "A regressive model for dynamic instabilities during the condensation of R404A and R507 refrigerants." International Journal of Heat and Mass Transfer 141 (October 2019): 1025–35. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2019.06.095.

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Greco, A., and G. P. Vanoli. "Flow-boiling of R22, R134a, R507, R404A and R410A inside a smooth horizontal tube." International Journal of Refrigeration 28, no. 6 (2005): 872–80. http://dx.doi.org/10.1016/j.ijrefrig.2005.01.008.

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Morrell, D. J., H. Dadi, J. More, et al. "A monoclonal antibody to human insulin-like growth factor-I: characterization, use in radioimmunoassay and effect on the biological activities of the growth factor." Journal of Molecular Endocrinology 2, no. 3 (1989): 201–6. http://dx.doi.org/10.1677/jme.0.0020201.

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ABSTRACT A monoclonal antibody (BPL-M23) to insulin-like growth factor-I (IGF-I) was obtained following immunization of BALB/c mice with human IGF-I conjugated to ovalbumin. The affinity constant of BPL-M23 for IGF-I was 10·5 litres/nmol and the cross-reactivities of IGF-II, multiplication-stimulating activity III-2 and insulin were 08, 003 and less than 0·0001 % respectively. Porcine, bovine, ovine and rabbit sera, but not rat or mouse sera, showed substantial reactivity with the antibody. Comparison of radioimmunoassay analyses of 54 human serum samples from normal subjects and acromegalic and GH-deficient patients using BPL-M23 and a polyclonal rabbit antiserum (R557A) to human IGF-I showed a high correlation, indicating the usefulness of the monoclonal antibody in radioimmunoassay. Monoclonal antibody BPL-M23 was capable of abolishing the sulphation, mitogenic and insulin-like activities of IGF-I in in-vitro bioassays, suggesting that these activities may rely upon the same receptor-binding site which is near to the antibody-binding site.

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