Thermal properties and morphology of crystal in nylon 1010 formed isothermally at melting peak temperature

1993 ◽  
Vol 40 (2) ◽  
pp. 689-695
Author(s):  
Fu Shuren ◽  
Zhang Guanghua ◽  
Tan Qun ◽  
Yang Yuqin
Keyword(s):  
Thermal Properties ◽  
Peak Temperature ◽  
Melting Peak ◽  
Nylon 1010 ◽  
Melting Peak Temperature

Physical Properties of Resistant Mungbean Starch Prepared by Enzyme and Acid Treatment

2012 ◽  
Vol 554-556 ◽  
pp. 1033-1037 ◽  
Author(s):  
Qing Jie Sun ◽  
Liu Xiong ◽  
Ben Xin Xing ◽  
Cui Xia Sun
Keyword(s):  
Thermal Properties ◽  
Physical Properties ◽  
Acid Hydrolysis ◽  
Resistant Starch ◽  
Acid Treatment ◽  
Crystal Form ◽  
Peak Temperature ◽  
Water Binding

The physical properties of enzyme and acid treated mungbean RS were studied. The crystal form was transformed into B type from C type with enzymatic and acid treatment.The solubility and transmittance decreased and mungbean RS content and the water-binding values increased with increase in enzyme and acid hydrolysis. The thermal properties observed by DSC showed a decrease in enthalpy of gelatinization (ΔH) and increases in onset (To), peak temperature (Tp) and conclusion temperature (Tc) upon enzyme and acid hydrolysis. The ratio of volume of resistant starch samples wasn’t much different. However, a significant reduction in starch pasting viscosity was observed with enzyme and acid treating

scholarly journals Thermal properties of radiolytically synthesized PVA/Ag nanocomposites

2007 ◽  
Vol 61 (3) ◽  
pp. 129-134 ◽  
Author(s):  
Aleksandra Krkljes ◽  
Zorica Kacarevic-Popovic
Keyword(s):  
Thermal Properties ◽  
Heating Rate ◽  
Melting Temperature ◽  
Melting Behavior ◽  
Melting Peak ◽  
Degree Of Crystallinity ◽  
High Heating Rate ◽  
Half Time ◽  
The Degree Of Crystallinity ◽  
Peak Melting Temperature

The radiolytic method was used to synthesize two types of nanocomposites with silver, PVA/Ag by film casting and PVA hydrogel/Ag nanocomposites. This method is particularly suitable for generating metal nanoparticles in solution. The radiolytic species (solvated electrons and secondary radicals) exhibit strong reducing properties such that metal ions are reduced at each encounter. Metal atoms then tend to grow into larger clusters. It was found that solid or swollen polymers are able to stabilize small crystallites against spontaneous growth via aggregation. Using differential scanning calorimetry (DSC), the melting behavior and kinetics of the PVA/Ag nanocomposites were investigated and compared to those of pure PVA. The melting as well as crystallization behavior of polymers is crucial because it governs the thermal properties, impact resistance and stress strain properties. Understanding the melting behavior is significant not only to tailor the properties of nanocomposites but to investigate the interactions between the constituents. The DSC curves of pure PVA and prepared nanocomposites show only one melting peak between 175 and 230?C, indicating that the melting behavior of these two systems are analogous. In both cases, with increasing heating rate, the melting peak shifts to a higher temperature, but with increasing Ag content the peak melting temperature is lower. When specimens are heated at high heating rate, the motion of PVA molecular chains cannot follow the heating temperature on time due to the influence of heat hysteresis, which leads to a higher peak melting temperature. When Ag nanoparticles are added they increase the heat transfer among the PVA molecular chains decreasing the melting temperature. The Ag content is a major factor affecting the degree of crystallinity. It was observed that at low nanofiller content, up to the 0.5 wt%, the degree of crystallinity of the nanocomposites increased, while at a higher content the crystallization was retarded. The half time of melting is non-linearly dependent on the amount of nanofiller. In the range from 0.25 to 1 wt% Ag it slightly increases, because at a low Ag content the nanoparticles act as a heterogeneous nucleation agent during the crystallization process. For large amounts of nanofiller, the half time of melting is markedly higher than for pure PVA. At a higher Ag content, the nanoparticles act as a barrier that restricts the thermal motion of PVA molecular chains and the half time of complete melting increases. The significantly lower melting activation energy of the nanocomposites with high amount of nanofiller compared to pure PVA, calculated by the Kissinger method, indicated that nanoparticles reduced the heat barrier for the melting process. .

Effects of Bismuth Content on the Microstructure, Shear Strength and Thermal Properties of Sn-0.7Cu-0.05Ni Solder Joints

2020 ◽  
Vol 982 ◽  
pp. 115-120
Author(s):  
Phairote Sungkhaphaitoon ◽  
Tanyaporn Suwansukho
Keyword(s):  
Shear Strength ◽  
Thermal Properties ◽  
Solder Joint ◽  
Intermetallic Compounds ◽  
Interfacial Layer ◽  
Solder Joints ◽  
Peak Temperature ◽  
Cu Substrate ◽  
Bismuth Content ◽  
Pasty Range

The effects of bismuth content on the microstructure, shear strength and thermal properties of Sn-0.7Cu-0.05Ni solder joints were investigated. Adding 2 wt% elemental Bi to Sn-0.7Cu-0.05Ni solder joints reduced peak temperature by about 6.7 °C, increased pasty range by 4.2 °C and raised undercooling by 3.1 °C. The microstructure of the interfacial layer between solder and Cu substrate was composed of (Cu,Ni)6Sn5 and (Cu,Ni)3Sn intermetallic compounds (IMCs). The solder joint included a phase of SnBi and Cu6Sn5 IMCs. The addition of elemental Bi increased shear strength and suppressed the growth of IMCs in the interfacial layer of the solder joints.

Synthesis, crystal structure, and thermal properties of Ni(NH3)4(AFT)2

2020 ◽  
pp. 174751982093947
Author(s):  
Shu-han Wei ◽  
Xiao Ma ◽  
Zi-mei Ding ◽  
Kang-zhen Xu ◽  
Hong-xu Gao ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Differential Scanning Calorimetry ◽  
Thermal Properties ◽  
Peak Temperature ◽  
Isothermal Kinetics ◽  
Scanning Calorimetry ◽  
Orthorhombic Crystal ◽  
Kinetics Parameters ◽  
Stability Parameters ◽  
Exothermic Decomposition

Ni(NH3)4(AFT)2 [NiC6H16N18O2, AFT = 4-amino-3-(5-tetrazolate)furazan] is synthesized and characterized by elemental analysis and Fourier-transform infrared spectroscopy for the first time. X-ray diffraction measurements are used to determine the crystal structure of compound 1. The results demonstrate that compound 1 crystallized in the orthorhombic crystal system. The nickel(II) ion is six-coordinated by N atoms from two AFT-ligands and four NH3 molecules. Its thermal properties are investigated by differential scanning calorimetry and thermogravimetry-derivative thermogravimetry methods, with the results demonstrating that the differential scanning calorimetry curve exhibits two endothermic and one exothermic processes. The endothermic processes are in the range of 130–510 °C with a peak temperature of 188 °C. The temperature from 230 to 400 °C is the exothermic process in which the peak temperature is 314.58 °C. In addition, Kissinger’s and Ozawa-Doyle’s methods are used for calculating the non-isothermal kinetics parameters. Moreover, the apparent activation energy ( E), safety, and thermal stability parameters ( TSADT, TTIT, Tb) for Ni(NH3)4(AFT)2 are calculated. In addition, the calculated thermodynamic functions ( ∆S≠, ∆H≠, and ∆G≠) for the exothermic decomposition process of Ni(NH3)4(AFT)2 are 55.07 J mol−1 K−1, 196.18 kJ mol−1, and 164.90 kJ mol−1, respectively.

The thermal properties of some amine tetraphenylboron salts8-Quinolinol and its derivatives

1960 ◽  
Vol 23 ◽  
pp. 332-336 ◽  
Author(s):  
W WENDLANDT ◽  
J VANTASSEL ◽  
G ROBERTHORTON
Keyword(s):  
Thermal Properties

Thermal properties of an erbium-doped fibre amplifier

1990 ◽  
Vol 137 (3) ◽  
pp. 155 ◽  
Author(s):  
C.A. Millar ◽  
T.J. Whitley ◽  
S.C. Fleming
Keyword(s):  
Thermal Properties ◽  
Fibre Amplifier ◽  
Erbium Doped
Sign in / Sign up

Export Citation Format

Share Document