Influence of the amorphous phase and preceding solution processing on the eutectic behaviour in the state diagram of P3HT : PC61BM determined by rapid heat–cool calorimetry

RSC Advances ◽  
2016 ◽  
Vol 6 (95) ◽  
pp. 92981-92988 ◽  
Author(s):  
M. Defour ◽  
N. Van den Brande ◽  
L. Van Lokeren ◽  
G. Van Assche ◽  
W. Maes ◽  
...  

Experimental determination of eutectic state diagrams for organic photovoltaics based on advanced calorimetry highlighting the importance of the amorphous phase.

2020 ◽  
Vol 303 ◽  
pp. 97-103
Author(s):  
V.A. Vlasov ◽  
Anatoliy A. Klopotov ◽  
V.I. Vereshchagin ◽  
O.G. Volokitin ◽  
K.A. Bezukhov ◽  
...  

The paper presents the results of the analysis of the state diagram of compounds in the system А12O3-SiO2. It has been found that the presence and the concentration of oxygen have a very important effect on formation of compounds with a crystalline structure in different syngony based on SIALON. Oxygen contributes to transition of the metastable AlXSi3-XN4compound into stable one. The parameter of structural “friability” of compounds has been used in the analysis of thethermodynamic stability of compounds in the Al-Si-N-O system. It has been foundthat the SiAl4O2N4 compound with the 12H-SIALON structure (Pearson symbol hP32) has the greatest thermodynamic stability among the compounds under study in this system.


2016 ◽  
Vol 848 ◽  
pp. 89-94
Author(s):  
Chutamas Boonrod ◽  
Khongsak Srikaeo

State diagram is a map of the different states of a food polymer as a function of water or solids content and temperature. The main advantage of drawing map is in identifying different states of a food polymer which helps in understanding the complex changes when food's water content and temperature are changed. It also assists in identifying food’s stability during storage as well as selecting suitable conditions for processing. This research successfully developed the state diagrams of two Thai rice varieties differing in amylose contents (San-pah-tawng and Phitsanulok 2) by measuring the glass line; glass transition temperature (Tg) vs. solids content, freezing curve; initial freezing point vs. solids content by using the differential scanning calorimetry (DSC) method. Rice with different amylose content exhibited similar freezing curves and glass transition patterns. The state diagrams obtained in this study are in agreement with previously published data. They can be useful in optimizing the drying and freezing processes as well as studying the physicochemical changes during storage of rice.


1935 ◽  
Vol 129 (1) ◽  
pp. 477-505 ◽  
Author(s):  
E. C. Smith

The paper describes an experimental determination of the mass flow of refrigerant per minute and refrigerating effect per minute in a vapour-compression refrigerator, when the state of the refrigerant at the exit from the evaporator was varied over a wide range of superheat temperatures and dryness fractions. The usual methods of measuring the flow of liquids in pipes were not suitable for the present work and a special type of flow meter, described in the text, was developed. The results obtained were not as theory would tend to suggest, but were substantially modified by practical conditions, particularly for dryness fractions between 0·97 and 0·87. The volumetric efficiency changed abruptly over this range from a higher to a lower value. The reduction was attributed to the effect of re-evaporation of. the liquid portion of the refrigerant in the compressor during the suction stroke, as it was found that the higher volumetric efficiency was obtained when the refrigerant was superheated throughout most of the delivery stroke, and the lower volumetric efficiency occurred when the state of the refrigerant on entering the compressor resulted in liquid being present in the cylinder at the end of the delivery stroke. The reduction in the volumetric efficiency resulted in a corresponding reduction in the mass flow, the refrigerating effect, and the heat rejected by the condenser per minute, and in the coefficient of performance for dryness fractions ranging between 0·97 and 0·87.


Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2077
Author(s):  
Pedro García-Coronado ◽  
Alma Flores-Ramírez ◽  
Alicia Grajales-Lagunes ◽  
Cesar Godínez-Hernández ◽  
Miguel Abud-Archila ◽  
...  

The state diagram, which is defined as a stability map of different states and phases of a food as a function of the solid content and temperature, is regarded as fundamental approach in the design and optimization of processes or storage procedures of food in the low-, intermediate-, and high-moisture domains. Therefore, in this study, the effects of maltodextrin addition on the freezing points (Tm′, Tm) and glass transition temperatures (Tg′, Tg) required for the construction of state diagrams of fruit juice model systems by using differential scanning calorimetry methods was investigated. A D-optimal experimental design was used to prepare a total of 25 anhydrous model food systems at various dry mass fractions of fructose, glucose, sucrose, pectin, citric acid, and maltodextrin, in which this last component varied between 0 and 0.8. It was found that maltodextrin mass fractions higher than 0.4 are required to induce significant increases of Tg′, Tm′, Tg, and Tm curves. From this perspective, maltodextrin is a good alternative as a cryoprotectant and as a carrier agent in the food industry. Furthermore, solute-composition-based mathematical models were developed to evaluate the influence of the chemical composition on the thermal transitions and to predict the state diagrams of fruit juices at different maltodextrin mass fractions.


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