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361.
The phase diagrams of binary organic faceted-faceted systems of p-dibromobenzene with acenaphthene, p-chloronitrobenzene and acetanilide show the formation of a simple eutectic with 0.53, 0.61, and 0.64 mole fraction of p-dibromobenzene, respectively. Crystallization data, determined by the capillary method, suggest that the eutectics of p-dibromobenzene with acenaphthene and p-chloronitrobenzene solidify with alternate nucleation mechanism and the crystallization of the eutectic of p-dibromobenzene-acetanilide system takes place by the side-by-side growth of the phases involved. With a view to throw light on the thermodynamic behaviour of eutectic alloys of non-metals, heats of fusion of their transparent organic analogues and their eutectics were determined, and using these values different thermodynamic parameters were calculated. The microstructures of the eutectics show their typical characteristic features. 相似文献
362.
In the present study, poly(N-Isopropylacrylacrylamide-co-N-tertiarybutylacrylamide-co-hydroxyethylcrylamide) (NIPAM-co-NTBA-co-HEAAm) hydrogels are prepared with variation of molar ratio of hydrophilic HEAAm and hydrophobic NTBA. The prepared hydrogels are characterized with elemental analysis and Fourier transform infrared (FTIR) spectroscopy. The thermodynamics of swelling properties of poly(NIPAM-co-NTBA-co-HEAAm) hydrogels have also been discussed. The experimental C/N ratios are comparable with the theoretical value. The enthalpy change of mixing ∆Hmix, entropy change of mixing ∆Smix, free energy change of mixing ∆Gmix are determined for swelling of hydrogels at 25 °C. The value of total free energy of hydrogel swelling is found to be negative which confirms the lower critical solution temperature (LCST) exhibited in all hydrogels and the volume change transition shows the thermoresponsive behavior. The values of ∆Smix increase and ∆Gmix decrease with increasing amount of hydrophobic NTBA content in the hydrogels. The values of free energy change of elasticity (∆Gel) are found to be increased with increasing the hydrophobic NTBA content followed by decrease in swelling percentage. Also, the transition temperature of the hydrogel is found to be decreased with increasing the hydrophobic NTBA. 相似文献
363.
Varun Kumar Sing Souvik Sur Mohd. Musharraf Ratan Kumar Dey Sanjay Kumar Swain Suman Shekhar 《Macromolecular Symposia》2024,413(1):2300045
In the present study, the degradation process of piperazine (PP) immobilized silica gel (SiPP) is investigated under dynamic conditions. The degradation of SiPP is studied with thermogravimetric analyzer (TGA). The kinetics of degradation process is analyzed by Kissinger method, Flynn–Wall–Ozawa's (FWO) method, and Deconvolution method. It is found that degradation of SiPP can be described by parallel independent two-portion process model, which includes two processing state of the system (marked by processes 1 and 2), where process 1 and 2 can be attributed to decomposition processes of organic moiety attached on silica surface. The apparent activation energy (Ea) is calculated by Flynn–Wall–Ozawa's (FWO) method and deconvolution method. 相似文献
364.
Bhavya Gera Yuvraj Singh Raghuvanshi Oshin Rawlley Shashank Gupta Amit Dua Parjanay Sharma 《International Journal of Communication Systems》2023,36(16):e5588
Many scholastic researches have begun around the globe about the competitive technological interventions like 5G communication networks and its challenges. The incipient technology of 6G networks has emerged to facilitate ultrareliable and low-latency applications for sustainable smart cities which are infeasible with the existing 4G/5G standards. Therefore, the advanced technologies like machine learning (ML), block chain, and Internet of Things (IoT) utilizing 6G network are leveraged to develop cost-efficient mechanisms to address the issues of excess communication overhead in the present state of the art. Initially, the authors discussed the key vision of 6G communication technologies, its core technologies (such as visible light communication [VLC] and THz), and the existing issues with the existing network generations (such as 5G and 4G). A detailed analysis of benefits, challenges, and applications of blockchain-enabled IoT devices with application verticals like Smart city, smart factory plus, automation, and XR that form the key highlights for 6G wireless communication network is also presented. In addition, the key applications and latest research of artificial intelligence (AI) in 6G are discussed facilitating the dynamic spectrum allocation mechanism and mobile edge computing. Lastly, an in-depth study of the existing open issues and challenges in green 6G communication network technology, as well as review of solutions and potential research recommendations are also presented. 相似文献