Kinetic parameter estimation for cooling crystallization process based on cell average technique and automatic differentiation

In this paper, a cell average technique(CAT) based parameter estimation method is proposed for cooling crystallization involved with particle growth, aggregation and breakage, by establishing a more efficient and accurate solution in terms of the automatic differentiation(AD) algorithm. To overcome the deficiency of CAT that demands high computation cost for implementation, a set of ordinary differential equations(ODEs) entailed from CAT based discretized population balance equation(PBE) are solved by using the AD based high-order Taylor expansion. Moreover, an AD based trust-region reflective(TRR) algorithm and another interior-point(IP) algorithm are established for estimating the kinetic parameters associated with particle growth, aggregation and breakage. As a result, the estimation accuracy can be further improved while the computation cost can be significantly reduced, compared to the existing algorithms. Benchmark examples from the literature are used to illustrate the accuracy and efficiency of the AD-based CAT, TRR and IP algorithms in comparison with the existing algorithms. Moreover, seeded batch cooling crystallization experiments of β form L-glutamic acid are performed to validate the proposed method.     

Technology commercialization on campus: twentieth century frameworks and twenty-first century blind spots

This paper uses an interpretive analysis to exam past and present developments in knowledge commercialization and provide researchers, policy makers, and university leaders an alternative framework. The model is based on historical precedent, and current economic realities, for effectively commercializing knowledge in the entrepreneurial age. While traditional technology transfer focused on an organizational centric approach, we propose an individual centric model of technology commercialization from universities. The move from an organization centric model to an individual centric model will likely follow past eras of change and innovation in higher education. The challenge for regional and university leadership is clear. Find methods and models for unleashing the knowledge across campus to solve local and regional challenges.     

Self-doped N-propansulfonic acid polyaniline-polyethylene terephthalate film used as active sensor element for humidity or gas detection

In this work, we report the fabrication of sensors’ element for humidity or gases, prepared by in situ polymerization of aniline N-propansulfonic acid using ammonium persulfate in acidic medium. The polymer is being used in the form of powder or deposited in multiple layers onto the PET film. Various techniques including Fourier Transform infrared (FTIR), ultraviolet-–visible spectroscopy (UV–vis), X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed to characterize the as-prepared sensing materials. The film has been tested for humidity influence, where the significant variations in electrical characteristics were observed, suggesting its usefulness for humidity sensors. Also, for different organic and inorganic gases, a relatively low operating temperature and important sensitivity were observed that indicate its applicability as an active element for general gases sensors. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47743.     

Cast Iron Inoculation Enhanced by Supplementary Oxy-sulfides Forming Elements

Inoculation is one of the most important metallurgical treatments applied to the molten cast iron immediately prior to casting, to promote solidification without excessive eutectic undercooling, which favors carbides formation usually with undesirable graphite morphologies. The paper focused on the separate addition of an inoculant enhancer alloy [S, O, oxy-sulfides forming elements] with a conventional Ca-FeSi alloy, in the production of gray and ductile cast irons. Carbides formation tendency decreased with improved graphite characteristics as an effect of the [Ca-FeSi + Enhancer] inoculation combination, when compared to other Ca/Ca, Ba/Ca, RE-FeSi alloy treatments. Adding an inoculant enhancer greatly enhances inoculation, lowers inoculant consumption up to 50% or more and avoids the need to use more costly inoculants, such as a rare earth bearing alloy. The Inoculation Specific Factor [ISF] was developed as a means to more realistically measure inoculant treatment efficiency. It compares the ratio between the improved characteristic level and total inoculant consumption for this effect. Addition of any of the commercial inoculants plus the inoculant enhancer offered outstanding inoculation power [increased ISF] even at higher solidification cooling rates, even though the total enhancer addition was at a small fraction of the amount of commercial inoculant used.     

Peculiarities in thermal evolution of precipitated amorphous calcium phosphates with an initial Ca/P ratio of 1:1

Thermal evolution of amorphous calcium phosphate (ACP) powder from a fast nitrate synthesis with a Ca/P ratio of 1:1 were studied in the range of 20–980?°C. The powder consisted of amorphous dicalcium phosphate anhydrate (CaHPO₄) after heating to 200?°C. CaHPO₄ gradually condensed to amorphous calcium pyrophosphate Ca₂P₂O₇ (CPP) between 200 to 620?°C. Amorphous CPP crystallized at 620–740?°C to a metastable polymorph α′-CPP of the high-temperature phase α-CPP and β-CPP. The α′-CPP/ β-CPP phase ratio reached a maximum at 800?°C (60?wt% α′-CPP/40?wt% β-CPP), and α′-CPP gradually transformed to β-CPP at a higher temperature. Some β-TCP occurred at 900?°C, so that a three-phasic mixture was obtained in the powder heated to 980?°C. The occurrence of metastable α′-CPP is attributed to Ostwald’s step rule, and a mechanism for β-TCP formation is proposed. The advantages of prospective biomaterials from these powders are discussed.     

Chitosan as template for the synthesis of ceria nanoparticles

Cerium oxide (CeO₂), nanoparticles were prepared using chitosan as template, cerium nitrate as a starting material and sodium hydroxide as a precipitating agent. The resultant ceria–chitosan spheres were calcined at 350 °C. The synthesized powders were characterized by, XRD, HRTEM, UV–vis, FTIR, and TG-DTA. The average size of the nanoparticles obtained was ∼4 nm and BET specific surface area ∼105 m² g⁻¹. Blueshifts in the ultraviolet absorption spectra have been observed in cerium oxide nanocrystallites. The band-gap was found to be 4.5 eV. The blueshifts are well explained for diameters down to less than a few nanometers by the change in the electronic band structure.     

Fabrication of Fischer–Tropsch Catalysts by Deposition of Iron Nanocrystals on Carbon Nanotubes

The fabrication of supported catalysts consisting of colloidal iron oxide nanocrystals with tunable size, geometry, and loading—homogeneously dispersed on carbon nanotube (CNT) supports—is described herein. The catalyst synthesis is performed in a two‐step approach. First, colloidal iron and iron oxide nanocrystals with a narrow size distribution are produced. Second, the nanocrystals are attached to CNT grains serving as support structure. Important features, like iron loading and nanocrystal density on the CNT support, are controlled by changing the nanocrystal concentration and ligand concentration, respectively. The Fischer–Tropsch performance reveals these new materials to be active, selective toward lower olefins (60% C of hydrocarbons produced in the absence of promoters), and remarkably stable against particle growth.     

Gene Expression Analyses Support Fallopian Tube Epithelium as the Cell of Origin of Epithelial Ovarian Cancer

Folate receptor alpha (FOLR1/FRA) is reported to be overexpressed in epithelial ovarian cancers (EOC), especially the serous histotype. Further, while dysregulation of the folate-dependent 1-carbon cycle has been implicated in tumorogenesis, little is known relative to the potential mechanism of action of FOLR1 expression in these processes. We therefore investigated the expression of FOLR1, other folate receptors, and genes within the 1-carbon cycle in samples of EOC, normal ovary and fallopian tube on a custom TaqMan Low Density Array. Also included on this array were known markers of EOC such as MSLN, MUC16 and HE4. While few differences were observed in the expression profiles of genes in the 1-carbon cycle, genes previously considered to be overexpressed in EOC (e.g., FOLR1, MSLN, MUC16 and HE4) showed significantly increased expression when comparing EOC to normal ovary. However, when the comparator was changed to normal fallopian tube, these differences were abolished, supporting the hypothesis that EOC derives from fallopian fimbriae and, further, that markers previously considered to be upregulated or overexpressed in EOC are most likely not of ovarian origin, but fallopian in derivation. Our findings therefore support the hypothesis that the cell of origin of EOC is tubal epithelium.