scholarly journals Review of pervaporation and vapor permeation process factors affecting the removal of water from industrial solvents

2019 ◽  
Vol 95 (3) ◽  
pp. 495-512 ◽  
Author(s):  
Leland M Vane
Processes ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 741
Author(s):  
Doinita-Roxana Cioroiu Tirpan ◽  
Ancaelena Eliza Sterpu ◽  
Claudia Irina Koncsag ◽  
Alina Georgiana Ciufu ◽  
Tănase Dobre

The aim of this study is to evaluate the potential of dried Cystoseira barbata alga for ethanol production through alcoholic fermentation. The influence of the main factors affecting the fermentation are studied in the frame of a 23 factorial experimental plan. The main factors influencing the process are the fermentation temperature (t from 25 °C to 35 °C), the solid to liquid ratio (S/L from 0.040 g/g to 0.080 g/g), and the cellulase ratio (R from 8 U/g d.m to 16 U/g d.m.). The maximum volatile compounds yield of 0.2808 g/g d.m and ethanol yield of 0.0158 g/g d.m were favored by the following experimental conditions: process temperature of 35 °C, solid to liquid ratio of 0.0415, and enzyme ratio of 16 U/g d.m. A statistical model was used to correlate the product yield with the process factors. Additionally, 19 interesting bioactive compounds were found in the enzymatic hydrolysis and alcoholic fermentation broths which seem likely to maintain natural defence mechanisms against diseases and physical disorders.


Author(s):  
Darrell R J Mullowney ◽  
Krista D Baker

Abstract A sex-asymmetric downward shift in size-at-terminal-molt has recently occurred in males in some portions of the Newfoundland and Labrador (NL) snow crab stock range, a first known occurrence for such processes in snow crab (Chionoecetes opilio) stocks. This study examines plausible factors promoting the shift in size-at-terminal-molt [synonymous with size-at-maturity (SaM)] including individual size, temperature, population density, and sex ratio. Analyses highlight expanse of cold water and large male density as being significant predictors of molt-type outcomes. A confluence of cold conditions and low density of large males promoted the SaM shift. In turn, the low male density was associated with recently elevated fishery exploitation rates under quota-controlled management. It remains unknown the extent to which the reduction in terminal size reflects a phenotypic vs. genotypic process. Factors affecting skip-molting in male snow crab are investigated, and we find that skip-molting occurs most frequently under extreme cold and high population density conditions. Potential complications arising from altered growth dynamics are discussed. Overall, the results advance knowledge on intraspecific competition processes within snow crab populations and inform fisheries management systems that male-only harvest strategies do not provide full protection from biological harm to aquatic resources through fishing.


2007 ◽  
Vol 340-341 ◽  
pp. 179-186
Author(s):  
Wing Bun Lee ◽  
Yi Ping Chen ◽  
Sandy To

A rate-dependent crystal plasticity constitutive model together with Marciniak- Kuczynski(M-K) approach is employed to perform numerical simulations of forming limits diagrams(FLDs). An initial imperfection in terms of a narrow band is adopted to initialize the sheet necking. Homogeneous deformations inside and outside the band are assumed and the enforcement of compatibility and equilibrium conditions is required only on the band interface. Constitutive computations are carried out on two aggregates of FCC crystal grains, with each representing one of the two zones, respectively. Taylor homogenization assumption is employed to establish the link of stress between single crystal and polycrystal, and to derive an average response of the aggregates. The same initial texture is imparted to the two aggregates and their evolutions will be traced in the necking process. Factors affecting the FLDs prediction, such as imperfection intensity, initial texture, strain rate sensitivity and crystal elasticity will be taken into account. The above procedure will be applied to an annealed aluminium alloy sheet metal


2021 ◽  
Vol 9 (4) ◽  
Author(s):  
Mai Nguyen Vu Ngoc ◽  
Nhiem Dao Ngoc ◽  
Chuc Pham Ngoc ◽  
Dung Doan Trung ◽  
Chi Nguyen Thi Ha ◽  
...  

In this study, nano Fe2O3 particles were synthesized by the combustion of gel from polyvinyl acohol (PVA) and tartaric acid (TA) for the degradation of methyl blue (MB) from the aqueous solution by the photocatalytic process. Factors affecting on Fe2O3 formation such as the pH of solution, temperature of gel formation, mole ratio of TA/PVA, temperature of calcination were investigated. The structure, morphology of Fe2O3 particles were characterized by analysis methods such as Differential Thermal Analysis, X- Ray Diffraction and Field Emission Scanning Electron Microscopy. The results showed that single-phase Fe2O3 was smaller than 60 nm of average grain size. When using Fe2O3 to investigate the photocatalytic capacity under the visible light irradiation, the results indicated that Fe2O3 catalysts showed a rather high photocatalytic ability to decompose MB. The intermediates coming from the photocatalytic degradation were identified.


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