scholarly journals Neutrino Cooling of Primordial Hot Regions

Symmetry ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 1442
Author(s):  
Konstantin Belotsky ◽  
Mohamed El Kasmi ◽  
Sergey Rubin
Keyword(s):  
Symmetry Breaking ◽  
Lower Limit ◽  
Particle Concentration ◽  
Initial Temperature ◽  
Nuclear Reactions ◽  
Threshold Effect ◽  
Final Temperature ◽  
Hot Matter ◽  
Density Inhomogeneities

The effect of neutrino cooling of possible primary regions filled by hot matter is discussed. Such regions could be obtained from the primordial density inhomogeneities and survive up to the modern epoch. The inhomogeneities could be caused by a symmetry breaking during the inflationary stage. We show that the final temperature of such region should be ∼10 keV provided that the initial temperature is within the interval 10 keV ÷ 100 MeV. The cooling is realized due to the weak nuclear reactions containing n−p transition. The lower limit 10keV is accounted for by suppression of the reactions rates because of the threshold effect and particle concentration decrease.

Symmetry breaking in statistical nuclear reactions: are two-state-models useful?

1990 ◽  
Vol 337 (1) ◽  
pp. 29-37
Author(s):  
M. Mayer ◽  
A. M�ller ◽  
H. L. Harney
Keyword(s):  
Symmetry Breaking ◽  
Nuclear Reactions ◽  
State Models

scholarly journals YIELD OF A PORTABLE SAWMILL AND WOOD DRYING OF Hovenia dulcis IN CONVENTIONAL KILN

FLORESTA ◽  
2018 ◽  
Vol 49 (1) ◽  
pp. 079
Author(s):  
Raquel Marchesan ◽  
Pedro Lício Loiola ◽  
Morgana Cristina França ◽  
Claudio Gumane Francisco Juízo ◽  
Márcio Pereira da Rocha ◽  
...  
Keyword(s):  
Initial Temperature ◽  
Operational Efficiency ◽  
Moisture Loss ◽  
Low Permeability ◽  
Drying Method ◽  
Drying Process ◽  
Diameter Class ◽  
Final Temperature ◽  
Conventional Kiln Drying ◽  
Hovenia Dulcis

The objective of this work was to evaluate the yield of sawn wood and the operational efficiency in the sawing of Hovenia dulcis logs in a portable sawmill, as well as to evaluate the behavior of the wood in conventional kiln drying. For this purpose, five trees were selected, from which 14 logs of 1.8  meters in length were obtained to determine the volume, the yield of two diametric classes (20 to 24 and 24.1 to 28 cm) and the operational efficiency during the sawing of the logs. For the drying process, the parameters of initial temperature, final temperature and drying potential were obtained from the drastic drying method at 100ºC. The yield results showed that there were no statistical differences between the two diametric grades. For operational efficiency, the highest diameter class (1.00m³/worker/day) was higher than the lower diameter class (0.70m²/worker/day). For the drying of Hovenia dulcis wood, it is possible to consider this species as a difficult drying type according to the parameters found for the elaboration of the drying programs. In addition, the moisture loss of the wood occurred slowly due to its low permeability.

COOLING CUSTARDS AND PUDDINGS WITH COLD-TUBE AGITATION1

1961 ◽  
Vol 24 (7) ◽  
pp. 207-210 ◽  
Author(s):  
Lenora Moragne ◽  
Karla Longrée ◽  
James C. White
Keyword(s):  
Initial Temperature ◽  
Cooling Time ◽  
Final Temperature ◽  
Low Level ◽  
High Level

This investigation is concerned with the cooling of 4-gal batches of custards and puddings from an initial temperature of 140°F to a final temperature of 60°F, using a rotating cold tube agitator. Variables were: (a) level of egg, (b) level of cornstarch, (c) level of sugar, and (d) rate of cold-tube agitation. Total cooling time decreased as the rate of agitation increased. All but one of the forty-eight mixtures cooled within 3 hr when agitated at 18 rev/min; all but five cooled within 5½ hr. when agitated at 6 rev/min. As the level of egg in the mixture increased the total cooling time decreased. As the level of sugar increased the total cooling time also increased, but the increase in total time was not in proportion to the increase in the level of sugar. In each instance, agitation at 18 rev/min produced a greater increase in radius of spread. Cornstarch was the most significant factor influencing the change in density of the mixtures. There was a greater increase in density value in the mixtures made with the high level of cornstarch than in the mixtures made with the low level of cornstarch. As the level of egg in the mixtures increased, the differences in density value also increased.

scholarly journals Kinetic Models of Integrated Solidification and Cementation of Cementformation Interface with New Method

2013 ◽  
Vol 7 (1) ◽  
pp. 9-17
Author(s):  
Jun Gu ◽  
Pei Zhong ◽  
Wenzheng Qin ◽  
Haoya Liu ◽  
Lifei Dong ◽  
...  
Keyword(s):  
Activation Energy ◽  
Kinetic Models ◽  
Initial Temperature ◽  
Reaction Order ◽  
Preexponential Factor ◽  
Exothermic Peak ◽  
Temperature Peak ◽  
Final Temperature ◽  
Natural Logarithm ◽  
Solidification Reaction

The isolation failure of cement-formation interface is an important and urgent problem in oil production, while an effective way to solve it is to realize the integrated solidification and cementation of cement-formation interface (ISCCFI). In order to study the kinetics of ISCCFI with MTA (Mud Cake to Agglomerated Cake) method, the Diamond Differential Scanning Calorimetry Analyzer is adopted for experiments with dynamic method and isothermal method. The results show that there is a linear relationship between the solidification reaction temperature and the heating rate of ISCCFI with MTA method. For the first exothermic peak, the initial temperature, peak tip temperature and final temperature are 53 °C, 69 °C and 83 °C respectively, and the apparent activation energy of solidification reaction is 44.39×10-3 kJ.;mol-1, the natural logarithm of preexponential factor is 7.26, the solidification reaction order is 0.88. For the second exothermic peak, the initial temperature, peak tip temperature and final temperature are 83 °C, 92 °C and 114 °C respectively, and the apparent activation energy of solidification reaction is 99.14×10-3 kJ.;mol-1, the natural logarithm of preexponential factor is 24.77, the solidification reaction order is 0.94. The maximum solidification reaction rates at 50 °C, 75 °C and 90 °C are 0.09×10-3 s-1, 0.27×10-3 s-1 and 0.51×10-3 s-1 respectively. The kinetic models of ISCCFI with MTA method under different temperatures are established. It provides a theoretical and technical support for the isolation improvement of cement-formation interface.

scholarly journals Hubungan Letak Aksial dan Variasi Ketebalan Papan terhadap Penyusunan Skedul Pengeringan Kayu Cemara Gunung (Casuarina Junghuhniana Miq.) (Relationship Between Axial Location and Board Thickness Variation on the Development of Drying Schedule of Cemara Gunung (Casuarina Junghuhniana Miq.))

2021 ◽  
Vol 9 (1) ◽  
pp. 121
Author(s):  
Hanan Purana Putera ◽  
Tomy Listyanto
Keyword(s):  
Initial Temperature ◽  
Axial Position ◽  
Thickness Variation ◽  
Final Temperature ◽  
Chi Square ◽  
Drying Characteristics ◽  
Axial Location ◽  
Board Thickness ◽  
C 50 ◽  
Chi Square Analysis

The research aimed to determine drying characteristics, developing drying schedule, and its relationship to the axial position of the sample on the stem, board thickness, specific gravity, and percentage of heartwood.This research used cemara gunung (Casuarina junghuhniana Miq.) as samples with 6 replications and 2 factors that are the axial location (bottom, middle, and top) and board thickness (2 cm, 3 cm, and 4 cm). The drying schedule development followed the Terazawa Method, in which the samples were dried within a temperature of 100°C for 72 h. The proper schedule was then applied and evaluated. The research obtained 11 variations of the drying schedule.The chi-square analysis results indicated that the board thickness and percentage of heartwood were significantly correlated with the development of the drying schedule. The drying schedule using board thickness of 2 cm, 3 cm, and 4 cm can be dried with an initial temperature of 60°C, 50°C, and 47°C, respectively. The wet-bulb depression was 4°C, 2°C, and 2°C, respectively, and the final temperature was 90°C, 80°C,and 65°C, respectively.  Keywords: axial, board-thickness, Casuarina junghuhniana, drying-schedule, Terazawa method

Investigation of the Initial Inverse Problem in the Heat Equation

2004 ◽  
Vol 126 (2) ◽  
pp. 294-296 ◽  
Author(s):  
Khalid Masood ◽  
F. D. Zaman
Keyword(s):  
Inverse Problem ◽  
Heat Conduction ◽  
Heat Equation ◽  
Initial Temperature ◽  
Final Temperature ◽  
Conduction Model ◽  
Heat Conduction Model ◽  
Ill Posed

We investigate the inverse problem in the heat equation involving the recovery of the initial temperature from measurements of the final temperature. This problem is extremely ill-posed and it is believed that only information in the first few modes can be recovered by classical methods. We will consider this problem with a regularizing parameter which approximates and regularizes the heat conduction model.

scholarly journals VII. On the specific heats of gases at constant volume.—Part III. The specific heat of carbon dioxide as a function of temperature

1894 ◽  
Vol 185 ◽  
pp. 961-981
Keyword(s):  
Carbon Dioxide ◽  
Critical Temperature ◽  
Specific Heat ◽  
Lower Limit ◽  
Latent Heat ◽  
Large Scale ◽  
Initial Temperature ◽  
Specific Heats ◽  
Upper Limit ◽  
Points Of Interest

The question of the dependence of the specific heat of carbon dioxide upon its density having been investigated, so far as is described in Part II., the further question remained over as to whether the specific heat of a gas is dependent upons range of temperature over which the gas is heated. The question was evidently within the power of the steam calorimeter to answer, provided arrangements were ride for varying the lower limit of temperature—the initial temperature. To vary upper limit by resorting to vapours other than steam would, on the large scale on which operations were being conducted, have been costly and troublesome, though not attended with any inaccuracy, as the experiments of Wirtz on the Heats of several vapours, determined by the method of condensation, appear show. It is to be observed, indeed, that the use of vapours other than water would .ow of operations being conducted upon smaller quantities of the gas, as it would be sy to find liquids whose vapours possessed a latent heat one-half or one-fourth as eat as that of water; and a construction necessitating but little loss of vapour at experiment could be easily contrived. In this case, also, it would be necessary provide a means of varying the initial temperature. Chiefly on the grounds of supense I decided upon the use of steam in conjunction with a means of altering the initial temperature. It appeared probable, too, that the alteration of the initial temperature between 10° and 100° would disclose the chief points of interest in these of the gas under consideration, the critical temperature lying within this range.

scholarly journals Influence of Different Frying Processes on the Flavor Characteristics and Sensory Profile of Garlic Oil

Molecules ◽  
2019 ◽  
Vol 24 (24) ◽  
pp. 4456 ◽  
Author(s):  
Jie Sun ◽  
Baoguo Sun ◽  
Fazheng Ren ◽  
Haitao Chen ◽  
Ning Zhang ◽  
...  
Keyword(s):  
Initial Temperature ◽  
Sensory Profile ◽  
Gas Chromatography Mass Spectrometry ◽  
Diallyl Disulfide ◽  
Least Squares Regression ◽  
Frying Temperature ◽  
Final Temperature ◽  
Dimethyl Trisulfide ◽  
Garlic Oil ◽  
Frying Process

Fried garlic oil has been widely used in traditional Chinese cuisine and, recently, has become increasingly popular in food manufacturing. In this study, the effects of different initial and final frying temperature on the flavor characteristics and sensory profile of fried garlic oil were investigated using solvent-assisted flavor evaporation (SAFE) combined with gas chromatography–mass spectrometry (GC–MS). Results showed that the content of flavor compounds changed significantly as the frying temperature was increased. The sample that was treated at an initial temperature of 115 °C and a final temperature of 155 °C contained the highest amount of thioethers and heterocycles, mainly comprising dimethyl trisulfide, diallyl disulfide, and 2-vinyl-4H-1,2-dithiin. Partial least-squares regression elucidated the sensory attributes of fried and roasted garlic, showing a high correlation with thioethers and pyrazines. Furthermore, changes in the 2,6-dimethylpyrazine, dimethyl trisulfide, and diallyl disulfide concentrations were detected every 5 °C during the frying process (initial temperature, 115 °C; final temperature, 155 °C). Dimethyl trisulfide and diallyl disulfide concentrations showed irregular, downward trends, while 2,6-dimethylpyrazine concentration exhibited an increasing trend.

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