A novel concept of hybrid cryogenic distillation network has been explored which maximizes the benefits of both desublimation or solid-vapor based separation as well as distillation or vapor-liquid equilibrium based separation during the separation of carbon dioxide from methane or natural gas. Process network synthesis has been performed for four case studies with high carbon dioxide (72 mole%) and medium carbon dioxide (50 mole%) natural gas feed streams. The benefits of optimal locations for cryogenic packed beds were investigated. A conventional cryogenic network consisting of multiple distillation columns with butane as additive for extractive distillation was also studied and presented in this paper. Process modeling of cryogenic distillation network with MESH equations was attempted using an integrated dual loop (C+3) convergence and the results were compared with Aspen Plus simulator for benchmarking. The prediction of solidification region was employed using experimental data from literature to avoid solidification regions in the column. The proposed hybrid cryogenic distillation network showed promising potential for energy and size reduction. 相似文献
The complex formation between anionic polyelectrolyte poly(acrylic acid sodium salt) [NaPAA] and surface active ionic liquid (SAIL) lauryl isoquinolinium bromide [C12iQuin][Br] in aqueous media has been investigated by surface tension, isothermal titration calorimetry (ITC), and conductance. The self‐assembled structures have been characterized using dynamic light scattering (DLS) and turbidity measurements. A range of surface parameters have been calculated from tensiometric measurements including critical micelle concentration (CMC), surface excess concentration (Γcmc), surface pressure at the interface (Πcmc), minimum area occupied at air–solvent interface (Amin), adsorption efficiency (pC20), and surface tension at the CMC (γcmc). The thermodynamic parameters, i.e., standard enthalpy of micellization , standard free energy of micellization (), and standard entropy of micellization () have also been evaluated. Four different stages of transitions, corresponding to the progressive formation of NaPAA–[C12iQuin][Br] complex (C1), critical aggregation concentration (CAC), critical saturation concentration (C3) and CMC have been observed owing to strong electrostatic and hydrophobic interactions. The results obtained from DLS and turbidity measurements show that size of the aggregates first decreases and then increases in the presence of polyelectrolyte. The binding isotherms obtained using isothermal titration calorimetry (ITC) show the concentration dependence as well as the highly cooperative nature of interactions corresponding to formation of polyelectrolyte–SAIL complexes. 相似文献
The effect of high-pressure processing on quality and shelf life of black tiger shrimp was studied. Shrimp was high-pressure processed at selected pressure levels of 100, 270, and 435 MPa for 5 min at room temperature (25?±?2 °C). Changes in physical, biochemical, and microbiological characteristics after processing and during subsequent chilled storage were examined for 35 days. After processing significant (P?<?0.05) increase in moisture content and parallel reduction in protein content was observed. No significant changes were observed in TVB-N and TMA-N levels of shrimp after processing; however, these significantly increased with storage. Whiteness index increased with pressure intensity imparting brighter and mildly cooked appearance. Pressure-induced hardening effect was observed, which showed decreasing trend during storage. The treated samples maintained lower viable counts throughout the storage, thus having better microbial quality than untreated sample. Shelf life was extended to 15 days in shrimp treated at 435 MPa compared with 5 days in untreated sample. Pressure treatment of 435 MPa was found to be most effective in preserving the quality and extending the shelf life of black tiger shrimp. 相似文献
The performance of a dual time of flight (TOF) spectrometer using two 24 cm×10 cm area X–Y position sensitive Multi-Wire Proportional Counters (MWPC) is reported. Good separation of compound nuclear fission channel from elastic, quasi-elastic and non-compound fission channels have been achieved. Time calibration of the spectrometer using a technique, dependent on the detector independence of the mass or kinetic energy distributions gave a three times better mass resolutions compared to the conventional calibration technique using elastically scattered projectiles in a heavy ion induced fission reaction. Detail experimental methods in determining fission fragment mass and angular distribution have been presented and discussed. 相似文献
Synthesis of an innovative material for temperature sensor based on carbon nano-fibers (CNFs) on p-Si substrates has been demonstrated. The CNF films were characterized by SEM, Raman and FTIR studies. First order Raman spectra indicated a G band at ~1597 cm?1 corresponding to the E2g tangential stretching mode of an ordered graphitic structure with sp2 hybridization and a D band located ~1350 cm?1 originated from disordered carbon. Gold fingers were deposited on the p-Si/CNF surface for resistance measurement. Temperature sensing properties were also investigated critically. Resistance changes with temperature (ΔR/R) in p-Si/CNF films are found to be significantly large 30–60% Very stable, reproducible and improved temperature sensing properties would make this material superior to commonly available temperature sensors. 相似文献
Floods are common and recurring natural hazards which damages is the destruction for society. Several regions of the world with different climatic conditions face the challenge of floods in different magnitudes. Here we estimate flood susceptibility based on Analytical neural network (ANN), Deep learning neural network (DLNN) and Deep boost (DB) algorithm approach. We also attempt to estimate the future rainfall scenario, using the General circulation model (GCM) with its ensemble. The Representative concentration pathway (RCP) scenario is employed for estimating the future rainfall in more an authentic way. The validation of all models was done with considering different indices and the results show that the DB model is most optimal as compared to the other models. According to the DB model, the spatial coverage of very low, low, moderate, high and very high flood prone region is 68.20%, 9.48%, 5.64%, 7.34% and 9.33% respectively. The approach and results in this research would be beneficial to take the decision in managing this natural hazard in a more efficient way.