Journal of The Chinese Institute of Chemical Engineers最新文献

Building a modeling capability for a physical phenomenon using differential equations is central to chemical engineering professionals. Using functional magnetic resonance imaging (fMRI), this work for the first time measures brain activities in partial differential equation reading and joke reading by selected professionals. Experimental results demonstrate that the equation message is first processed by the primary visual cortex (V1), and is then sent to Brodmann area 7 for information integration, and Broca's area (Brodmann area 44), Wernicke's area, and the fusiform gyrus to interpret its abstract meaning. The brain handles the differential equation as a syllabary rather than a character, and remembers the equation based on its shape rather than its identity.

The hot topic in cancer therapy, human epidermal growth factor receptor 2 protein (HER2), have been indicated that the overexpression of HER2 associated with ovarian, esophageal, gastric and breast cancers recently. To investigate the novel tyrosine kinase inhibitor of HER2 receptor, we employed the molecular simulation and structure-based drug design. Compounds from our laboratory database and two control kinase inhibitors, Tarceva and Iressa, were employed to dock into the HER2 ATP binding site. Three candidates with the highest dockscore were used for De Novo Evolution and 24 virtual compounds were generated. We found that the key residue, Phe731, would construct the pi-stacking interaction with both Tarceva and Iressa was conclusively regarded as the key residue for the inhibitory efficiency. The addition of 1,5-dimethyl-1H-imidazole group on compound A₁ produced the extra hydrophobic interaction, and the pi-stacking interaction with Phe731 was generated by the same aromatic group on both compound A and A₁. Although compound B₁ and C₁ could not produce the pi-stacking interaction with Phe731, both compounds which possessed the lower binding energy and higher dockscore than the two control compounds were believed to compete with the ATP molecule. Compound A₁, B₁ and C₁ were suggested the potent ATP-competitive inhibitors through the significant scores, binding affinity, hydrogen bond linkages and pi-stacking interaction, and these scaffolds were proposed for further drug design.

A remediation process, which combines the micellar solubilization and the cloud-point extraction technique by a nonionic surfactant Tergitol 15-S-7, was used to decontaminate phenanthrene, as a model hydrophobic pollutant, from spiked sand samples. A first-order kinetics model was employed to describe the solubilization behavior of phenanthrene well. It was observed that presence of surfactant decreased the mass-transfer coefficient of phenanthrene from sand surface to surfactant solutions, however, higher solubilization rate was obtained due to enhanced aqueous solubility and, thus, the larger driving force resulted from solublization. Cloud-point extraction was used to concentrate the phenanthrene solubilized in the washing solutions in an attempt to minimize the amount of wastewater. The extraction was carried out, subsequently, at room temperature by adding sodium sulfate to suppress the cloud-point low enough to induce phase-separation of the surfactant-rich phase with a minimal phase volume from the coexisting water phase. Recoveries higher than 93% were achieved in the combined process of micellar solubilization and cloud-point extraction on ultimate removal of immobilized phenanthrene sorbed on sands. The results showed that this combined process is efficient in recovering phenanthrene sorbed and immobilized on sands from contaminated sites, and produces only minimal amount of wastewater, i.e. less than 3% of its original volume.

The optimal plate aspect ratios for the best recovery of deuterium from water–isotope mixture in flat-plate thermal diffusion columns with transverse sampling streams have been determined. The maximum recovery and maximum production rate are achieved without changing the total expenditure, while the design with minimum plate surface area results in minimizing the total expense.

Vapor–liquid equilibrium (VLE) at 101.3 kPa have been determined for a ternary system (tetrahydofuran + 2-propanol + 2,2,4-trimethylpentane) and its constituent binary systems (tetrahydrofuran + 2-propanol, tetrahydrofuran + 2,2,4-trimethylpentane, and 2-propanol + 2,2,4-trimethylpentane). The activity coefficients of liquid mixtures were calculated from the modified Raoult's law. Thermodynamic consistency tests were performed for all VLE data. The VLE data of the binary mixtures and ternary mixtures were correlated using the Margules, Wilson, NRTL, and UNIQUAC activity-coefficient models. The models with their best-fitted interaction parameters of the binary systems were used to predict the ternary vapor–liquid equilibrium. All VLE data are also used to calculate the reduced excess molar Gibbs free energy g^E/RT and the deviations in the boiling point ΔT. The calculated quantities of g^E/RT and ΔT were fitted to variable-degree polynomials in terms of liquid composition.

This study analyzed convective drying of wastewater sludge cakes with three-dimensional cake structures probed using an X-ray micro-computerized tomography scanner (micro-CT), considering the development of cracks and cake morphology. The presence of artificial cracks on cake surface assist drying, but those occurred naturally cannot. The cake surface is noted far from saturation over drying. Moreover, the cracks transport easily moisture to cake surface, hence yielding high surface humidity (and rates) for drying. Comprehensive drying model has to incorporate real boundary conditions for success modeling.

Penicillin G acylase (PGA) is one of the most important enzymes for the production of semi-synthetic β-lactam antibiotics and their key intermediates. Purification of penicillin G acylase from fermentation broth with the aid of high-throughput screening (HTS) process has been examined in this study. We used a microtiter-plate based on screening method to find appropriate purification conditions for the target protein. The screening method is based on a 96-well plate format, and different matrices and conditions (pH, salt concentration and type) were tested. Through analyses of all pooled fractions (flow-through and elution) we gained appropriate information to choose the best performing matrix and buffer conditions for upscaling. After an upscaled purification step the second unit operation is screened in the similar way and parameters for this operation can be chosen. The purification parameter of purified PGA at the small-screen and upscaling levels were measured, respectively. The results indicate that high-throughput progress based on a 96-well plate is a flexible and efficient paradigm for recombinant protein purification.

Because of increasing interest in environmentally benign fabrication process, the use of dry cleaning processes to remove residues of metal, photoresists, organic moieties and particles from surfaces has grown as a research area. In this study, we designed series of systematic approaches to understand the properties of the hard-baked photoresist on glass substrates. We focused on the effects of de-bonding photoresists on the surface by using a plasma-assisted supercritical carbon dioxide removal process with various control parameters. Changes in the surface morphology of plasma de-bonded photoresists were observed and analyzed. A weight-loss method was used to evaluate quantitatively the efficiency of photoresist stripping by SCCO₂. Compared to the blank experiment (SCCO₂ process only), the photoresist residue reduces to 14.7% from 76.3%. This study demonstrates the possibility of incorporating plasma pretreatment into the supercritical carbon dioxide removal process for photoresist stripping applications.

In this work, hydrodynamic behavior of flow in three different reactor clarifiers was simulated by three-dimensional, multiphase flow model. The primary construction of reactor clarifier was based on the Bansin Water Treatment Plant, Taiwan. This is the traditional construction, and we call it Type A. The other two were designed in such a way as to improve effluent water quality. The traditional clarifier construction was varied in these to make a large well angle (Type B) and a gradually larger inlet pipe (Type C). Solid effluent flux can be calculated directly from this model. The simulation results showed that under the same daily throughput, the Type C construction of clarifier could decrease upflow fluid velocity in the clarifier and, therefore, reduce effluent water turbidity.

The present study is aimed at developing an enzymatic/acid-catalyzed hybrid process for biodiesel production using soybean oil as feedstock. In the enzymatic hydrolysis, 88% of the oil taken initially was hydrolyzed by binary immobilized lipase after 5 h under optimal conditions. The hydrolysate was further used in acid-catalyzed esterification for biodiesel production and the effects of temperature, catalyst concentration, feedstock to methanol molar ratio, and reaction time on biodiesel conversion were investigated. By using a feedstock to methanol molar ratio of 1:15 and a sulfuric acid concentration of 2.5%, a biodiesel conversion of 99% was obtained after 12 h of reaction at 50 °C. The biodiesel produced by this process met the American Society for Testing and Materials (ASTM) standard. This hybrid process may open a way for biodiesel production using unrefined and used oil as feedstock.