COMPUTER-AIDED GRAPHICS OF LIQUID-LIQUID EXTRACTION

An algorithm has been developed and tested for steady-state liquid-liquid extraction, using rectangular coordinates. It is capable of handling common types of stagewise contact, i.e., single stage extraction, multistage cross-current, and continuous countercurrent multistage extraction. The results depend on the nature of the extraction scheme and the extent of separation desired. While equilibrium data for some systems are stored in its data bank, the present portable computer simulator ( LIQEXT) has the flexibility of reading equilibrium data for other systems, as well as overriding stored data

Both design and rating cases can be performed. In the design mode, i.e., given the feed and solvent rates and the outlet concentration, it calculates the number of stages, the exit stream flow rates, and the concentration profile. In the rating ( or simulation) mode, i.e., given the feed and solvent rates, and the number of stages, it computes the exit streams flow rates and compositions, and the concentration profile. In both cases a graphical output of the concentration profile is produced, either on the screen or on a hard-copy plotter.     

Implementing two methods in GIS software for indoor routing: an empirical study

Multimedia Tools and Applications - With increasing demands for indoor GIS, indoor routing and analysis attracts attention from both GIS and architecture worlds. This paper aimes to provide...     

Creep-resistant dextran-based polyurethane foam as a candidate scaffold for bone tissue engineering: Synthesis,chemico-physical characterization,and in vitro and in vivo biocompatibility

A highly crosslinked composite dextran-based scaffold (named DexFoam) was tailored to overcome specific deficiencies of polymeric and ceramic bone scaffolds and to guarantee a bone-mimicking microenvironment for the proliferation of human mesenchymal stem cells in vitro. The creep resistance for up to 90% compressive stain, the capability to regain the original shape after deformation, and the good thermal stability in both physiological and “body limit” conditions make DexFoam a valid alternative to the currently available bone scaffolds. Histopathological evaluation for host reaction and tissue colonization of DexFoam scaffold, implanted subcutaneously in mice, demonstrated its in vivo biocompatibility and biodegradability.     

Retention of Eucalyptol,a Natural Volatile Insecticide,in Delivery Systems Based on Hydroxypropyl‐β‐Cyclodextrin and Liposomes

Eucalyptol (Euc) is a natural monoterpene with insecticide effects. Being highly volatile and sensitive to ambient conditions, its encapsulation would enlarge its application. Euc‐loaded conventional liposomes (CL), cyclodextrin/drug inclusion complex, and drug‐in‐cyclodextrin‐in‐liposomes (DCL) are prepared to protect Euc from degradation, reduce its evaporation, and provide its controlled release. The liposomal suspension is freeze‐dried using hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD) as cryoprotectant. The liposomes are characterized before and after freeze‐drying. The effect of Euc on the fluidity of liposomal membrane is also examined. A release study of Euc from delivery systems, in powder and reconstituted forms, is performed by multiple head extraction at 60 °C after 6 months of storage at 4 °C. CL and DCL suspensions are homogeneous, show nanometric vesicles size, spherical shape, and negative surface charge before and after freeze‐drying. Moreover, HP‐β‐CD does not affect the fluidity of liposomes. CL formulations present a weak encapsulation for Euc. The loading capacity of eucalyptol in DCL is 38 times higher than that in CL formulation. In addition, freeze‐dried DCL and HP‐β‐CD/Euc inclusion complex show a higher retention of eucalyptol than CL delivery system. Both carrier systems HP‐β‐CD/Euc and Euc‐loaded DCL decrease Euc evaporation and improve its retention. Practical Applications: Eucalyptol is a natural insecticide. It is highly volatile and poorly soluble in water. To enlarge its application, its encapsulation in three delivery systems (conventional liposomes, cyclodextrin/drug inclusion complex, combined system composed of cyclodextrin inclusion complex and liposome) is studied. In this paper it is proved that cyclodextrin/eucalyptol inclusion complex and eucalyptol‐in‐cyclodextrin‐in‐liposome are effective delivery systems for encalyptol encapsulation, retention, and release.     

Interferometric fibre-optic sensor using a short-coherence-length source

A fibre-optic sensor system exploiting the principles of white-light interferometry is demonstrated. A digital feedback servo ensures that theMach-Zehnder interferometric system is maintained at near-zero optical path difference.     

Minor Intron Splicing from Basic Science to Disease

Pre-mRNA splicing is an essential step in gene expression and is catalyzed by two machineries in eukaryotes: the major (U2 type) and minor (U12 type) spliceosomes. While the majority of introns in humans are U2 type, less than 0.4% are U12 type, also known as minor introns (mi-INTs), and require a specialized spliceosome composed of U11, U12, U4atac, U5, and U6atac snRNPs. The high evolutionary conservation and apparent splicing inefficiency of U12 introns have set them apart from their major counterparts and led to speculations on the purpose for their existence. However, recent studies challenged the simple concept of mi-INTs splicing inefficiency due to low abundance of their spliceosome and confirmed their regulatory role in alternative splicing, significantly impacting the expression of their host genes. Additionally, a growing list of minor spliceosome-associated diseases with tissue-specific pathologies affirmed the importance of minor splicing as a key regulatory pathway, which when deregulated could lead to tissue-specific pathologies due to specific alterations in the expression of some minor-intron-containing genes. Consequently, uncovering how mi-INTs splicing is regulated in a tissue-specific manner would allow for better understanding of disease pathogenesis and pave the way for novel therapies, which we highlight in this review.     

Investigation of the viscoelastic response of high temperature AS4‐12K/RP46 composites using a micromechanical approach

The viscoelastic behavior of a RP46 polyimide resin is characterized at high temperature and the results are used within a micromechanical model to predict the viscoelastic response of a RP46 based carbon fiber composite. The creep master curve of the neat resin is obtained using the time temperature superposition principle (TTSP) from creep tests at three different temperatures, namely 180, 220, and 270°C. The viscoelastic behavior of RP46 is modeled based on Schapery's single integral constitutive equation whose Prony Series coefficients are obtained from the master curve. The acquired properties are then incorporated into a Simplified Unit Cell Micromechanical model to study the creep response of a RP46 resin based composite system. The advantage of this particular micromechanical model lies in its ability to give closed form expressions for the effective viscoelastic response of unidirectional composites as well as each of their constituents. Two types of nonlinearities were observed, one due to stress and the other due to temperature. Both of these nonlinearities can be modeled through the use of proper coefficients in the constitutive equation of the matrix material. The model predictions are found to be in good agreement with experimental results obtained from tests conducted on the RP46 resin based composite system. POLYM. COMPOS., 37:1407–1414, 2016. © 2014 Society of Plastics Engineers     

Differential thermal analysis,thermal gravimetric analysis,and solid phase micro-extraction gas chromatography analysis of water and fuel absorption in diesel soot

An experimental investigation was conducted to analyze the absorption characteristics of deposited diesel soot by differential thermal analysis, thermal gravimetric analysis, and solid phase micro-extraction gas chromatography analysis. The results showed that dry diesel soot contained 2–3%w (percent by weight) of water and a maximum of 5%w hydrocarbons. Water wetted soot contained up to 40%w water, while diesel wetted soot contained up to 60%w hydrocarbons. The hydrocarbons extracted from the soot were primarily hydrocarbons higher than C₁₂H₂₆ with little evidence of lighter hydrocarbons.     

CO<Subscript>2</Subscript>-laser treatment of indium tin oxide nanoparticle coatings on flexible polyethyleneterephthalate substrates

A CO₂-laser treatment was used to improve the electrical conductivity of coatings of indium tin oxide (ITO) nanoparticles on flexible polyethyleneterephthalate (PET) substrates. The electrical conductivity and the transparency of CO₂-laser-treated ITO nanoparticle coatings were characterized with regard to the application as transparent electrodes. Furthermore, the stability of the electrical conductivity under oscillatory bending was investigated. A specific resistance of 0.12 Ω cm is obtained by CO₂-laser treatment without thermally damaging the PET film. The improvement of the electrical conductivity can be explained by a slight sinter neck formation. For a film thickness of 3 μm, a sheet resistance of 400 Ω/□ and a transmission in the visible range of 80% were achieved. The stability of the electrical conductivity of CO₂-laser-treated ITO nanoparticle coatings under bending was investigated using a specially constructed device for the application of various oscillatory bending loads. For a bending radius of 10 mm, the sheet resistance does not exceed 1000 Ω/□ after 300 bending cycles. Compared to commercial sputtered ITO coatings, CO₂-laser-treated ITO nanoparticle coatings show a significant higher stability under oscillatory bending.