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Industrial processes are always on the lookout for the improvement of efficiencies through process and material design. Nanofluids entailing a dispersion of nanoparticles in a base fluid have garnered attention to their superior performance, while bionanofluids take this a step further in introducing bioconvection, accounting for the swimming motion of gyrotactic microorganisms. Their promising application potential makes them a topic of much interest through research and industrial development. This chapter works through reviews and presents information starting with the preparation and stabilization methods and principles of nanofluids to their current applications, focusing on mass transfer processes of bionanofluids. The chapter then reviews the various types of mass transfer processes, investigating the mechanism of enhanced mass transfer, moving onto mathematical modeling to understand the parity between mass and heat transfer. The review then delves into bionanofluids, their applications in mass transfer, and an elucidation of the models of their mass transfer. A conclusion and the future outlook are finally presented.

The increasing demand for wearable bioelectronic devices has driven tremendous research effort on the fabrication of bioelectronics in microscale. To ensure the functionality and reliability, wearable bioelectronics need to be integrated with independent and internal energy storage systems to avoid frequent charging process from external sources. The supercapacitors has been considered as an electric energy source due to benefits such as a long cycle life, a high power density and fast charge–discharge rate. Miniaturization, biocompatibility, and biodegradability are the primary keys to achieving the requisites for implantable supercapacitors. Rapid, in situ 3D printing of implantable bioelectronic devices can address these needs. However, in situ 3D printing of bioelectronics using currently available materials has remained challenging due to their suboptimal physicochemical properties. Here, we present a novel material platform based on bio ionic liquid (BIL) functionalized biopolymers which can form a hydrogel electrolyte when exposed to visible light. Fine-structure, interdigitated, biocompatible, and implantable soft micro-supercapacitors (MSC) were created by 3D in situ bioprinting of these polymer electrolytes in combination with rheologically optimized graphene hydrogel-laponite (GH-L) blend as electrode material. The hydrogel electrolyte had a specific capacitance of ~ 200F/g, while the MSC had a specific capacitance of ~ 16 μF/g at a current density of 1 A/g, volumetric capacitance of ~ 44 μF/cm3, cyclic stability up to 10,000 cycles, energy densities nearly as high as implantable batteries, and a power density level of implantable supercapacitors. This novel material platform enables in situ 3D printing of flexible bioelectronics structures with integrated life-long power source.

In this paper a simple electrochemical sensing of dopamine by a new effective immobilization of tyrosinase (Tyr) enzyme on eggshell membrane (ESM) along with silver nanoparticles (AgNPs) is reported. The modified membrane was characterized by scanning electron microscope (SEM), energy dispersive spectroscopy (EDAX), X-Ray diffraction (XRD). A simple solution based approach was used to prepare AgNPs on biomembrane followed by glutaraldehyde activation to immobilize Tyr on the nanoparticles decorated ESM. The direct electrochemistry of DA oxidation was performed through cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Characterization of membrane was accomplished by electrochemical impedance spectroscopy (EIS). Prepared electrode showed very good stability, reproducibility, high selectivity, easy preparation and regeneration of electrode. The proposed sensor exhibited low detection limits 1.7ngL

We report here a novel synergistic catalysis system combined with porous organic polymeric solid acid (H-PDVB-SO3H) and K2O doped porous γ-Al2O3 solid base (γ-Al2O3-K2O). H-PDVB-SO3H and γ-Al2O3-K2O have abundant nanopores, controllable surface wettability, and high concentrations of acidic and basic sites. The synergistic catalysis system exploited by us could efficiently transform acidulated bone oil and plant oil into high quality biodiesel under mild conditions, which achieved ASTM specifications pertaining to acid number and total and free glycerin. Acidulated bone is a bone meal treated with sulfuric acid containing high-value hydrocarbons, which is generated in large amounts by the cattle industry. This work develops an efficient and cost-effective approach to transform animal waste into high quality biodiesel.

Adsorbents of mesoporous polymeric networks of divinylbenzene (PDVB) with different functionalities were synthesized by simple hydrothermal treatment of divinylbenzene (DVB) with co-monomers of vinylimidazole (VI) and 3-((3-(cyclohexylamino)propyl)thio)propyl methacrylate (ACAM) which resulted in P(DVB-VI) and P(DVB-ACAM) respectively. The CO2 adsorptive properties of PDVB were compared with the functionalized polymers. Although incorporation of ACAM monomer leads to loss of surface area, the functional groups of amine, thiol, and ester on P(DVB-ACAM) provide favorable sites for CO2 molecules to be adsorbed more efficiently in comparison with non-functionalized PDVB. The amine/thiol functionalized adsorbent, P(DVB-ACAM), also showed high selectivity and regenerability with the heat of adsorption of >70 kJ/mol indicating chemical interactions of active sites with CO2 at low adsorption limit and physical adsorption at higher adsorptions.

Policy changes in anthropogenic CO2 reduction are increasingly looking at the simultaneous development of attractive technologies that integrate its industrial utilization in valorizing the captured CO2 to fuel. Carbonaceous nanoadsorbents are attractive regenerative materials allowing for derivation from waste precursors, which makes them cost-effective and efficient for the given purpose. This chapter aims to review solid carbon-based nanoadsorbents for use in carbon dioxide capture traversing through their sources, chemistries, and mechanisms of adsorption and including structural developments aimed at carbon dioxide capture. As a conclusion, it is deemed that the future outlook will veer toward structures with industrial production and engineering feasibility, especially those that entail both precursors with waste valorization and integration with clean energy technologies such as solar for conversion of captured waste CO2 to fuel.

With an increasing policy impetus toward green technologies, the importance of mitigating anthropogenic carbon emission cannot be overstressed via the development and scaling of carbon capture, storage, and utilization technologies. The processes involve a series of steps, each with unique challenges of materials and process costs. In addition, each process must look at its footprint on the energy utilization, industrial feasibility, safety, environment, and global warming. This chapter gives a brief overview of the challenges in carbon dioxide capture and utilization processes by reviewing traditional and novel methods and recognizes the importance of the thermodynamic and process feasibility trade-off. It must be recognized that technologies need to overcome the impediment of cost-effective industrial retrofitting. The future potential thus lies in the hands of optimized hybrid processes.

This work explores the novel one-pot aqueous phase synthesis of mesoporous phenolic-hyperbranched polyethyleneimine resins without the use of a template, and their utility as heterogeneous catalysts in batch reactors and continuous microreactors. Catalyst surface areas of up to 432 m2/g were achieved with a uniform Pd distribution and an interconnected, highly porous, network structure, confirmed through Brunauer&ndash, Emmett&ndash, Teller (BET) surface area measurements, scanning electron microscopes (SEM), X-Ray Photoelectron Spectroscopy (XPS), Transmission Electron Microscopy (TEM), and Energy-dispersive X-ray spectroscopy (EDS). The heterogeneous catalysts achieved a maximum 98.98 &plusmn, 1% conversion in batch Suzuki couplings, with conversions being dependent upon reaction conditions, reactant chemistries, Pd loading and catalyst surface area. The catalysts were shown to be recyclable with only a marginal loss in conversion achieved after five runs. Up to 62 &plusmn, 5% and 46.5 &plusmn, 8% conversions at 0.2 mL/s and 0.4 mL/s flow rates, respectively, were achieved in a continuous microreactor. Understanding the mechanism of action of this mesoporous resin is a future research area, which could help expand the application vistas for this catalyst platform.

Adhesion to wet and dynamic surfaces is vital for many biomedical applications. However, the development of effective tissue adhesives has been challenged by the required combination of properties, which includes mechanical similarity to the native tissue, high adhesion to wet surfaces, hemostatic properties, biodegradability, high biocompatibility, and ease of use. In this study, we report a novel bioinspired design with bioionic liquid (BIL) conjugated polymers to engineer multifunctional highly sticky, biodegradable, biocompatible, and hemostatic adhesives. Choline-based BIL is a structural precursor of the phospholipid bilayer in the cell membrane. We show that the conjugation of choline molecules to naturally derived polymers (i.e., gelatin) and synthetic polymers (i.e., polyethylene glycol) significantly increases their adhesive strength and hemostatic properties. Synthetic or natural polymers and BILs were mixed at room temperature and cross-linked via visible light photopolymerization to make hydrogels with tunable mechanical, physical, adhesive, and hemostatic properties. The hydrogel adhesive exhibits a close to 50% decrease in the total blood volume loss in tail cut and liver laceration rat animal models compared to the control. This technology platform for adhesives is expected to have further reaching application vistas from tissue repair to wound dressings and the attachment of flexible electronics.

This paper presents a new class of octamethylcyclotetrasiloxane (D4 siloxane) adsorbent based on the copolymer of divinylbenzene and a novel methacrylate monomer. The novel cyclic amine based methacrylate monomer was synthesized employing click chemistry and was polymerized to form a mesoporous adsorbent under solvothermal conditions and tested for siloxane removal. The D4 adsorption capacity of the novel adsorbent is 2220 mg g−1, which is greater than the adsorption capacities of mesoporous poly(divinylbenzene) and commercial activated charcoal. The adsorbent retains 47% regeneration capacity after 10 usage cycles. The high specific adsorption is due to a combination of physisorption, caused by the mesoporosity and pore volume and chemisorption, as evidenced by spectroscopic results. The incorporation of functional groups into a mesoporous structure with significantly enhanced specific adsorption offers future opportunities towards tailored polymer properties for efficient industrial applications in siloxane removal.

This work reports the synthesis of a novel allylcyclohexylamine functionalized siloxane and its phase separated blend with styrene-butyl acrylate copolymer and their application for pervaporative enrichment of 1,3-propanediol from dilute aqueous solutions. The phase separated blend allowed for the recovery of mechanical strength lost due to functionalization without loss in separation performance. Separation factors of 9–15 were achieved with functionalization levels of 50–90%, while 1,3-propanediol flux was 1.5×10 −3 –1.6×10 −3 g/m 2 -s (5.5–5.8 g/m 2 -h). Separation efficiency increased with functionalization and decreased with increasing temperature and feed concentration. Solution diffusion model was used to compute the overall mass transfer coefficients, concentration polarization and intrinsic material mass transport properties. The overall mass transfer coefficient for 1,3-propanediol was between 1.0×10 −7 –1.4×10 −7 m/s while the boundary layer mass transfer coefficient ranged from 5×10 −7 m/s to 18×10 −7 m/s indicating the dominance of the membrane on the transport resistance. A computation of Hansens solubility parameters by a group contribution method was carried out to underscore the results. The membrane, with its good cost/performance tradeoff and excellent mechanical integrity, offers the possibility of fabrication into modules and scale up.

This work reports a novel two dimensional approach to the theoretical computation of the glass transition temperature in simple hypothetical icosahedral packed structures based on Thin Film metallic glasses using liquid state theories in the realm of transport properties. The model starts from Navier-Stokes equation and evaluates the statistical average velocity of each different species of atom under the condition of ensemble equality to compute diffusion lengths and the diffusion coefficients as a function of temperature. The additional correction brought in is that of the limited states due to tethering of one nodule vis -a-vis the others. The movement of the molecules use our Twin Cell Model a typical model pertinent for modeling chain motions. A temperature viscosity correction by Cohen and Grest is included through the temperature dependence of the relaxation times for glass formers.

The study of ion transport in biological system has become a topic of great current interest. This work presents the diffusive transport properties through a typical semi interpenetrating polymeric network (SIPN) which mimics many characteristic features of the walls of human food pipes. The SIPN matrix has been synthesised from Polyvinyl alcohol, Acrylamide monomer, Glutaraldehyde and Ammonium Per sulphate in our laboratory is utilised to study the diffusive transport in the absence and presence of aqueous electrolyte (KCl) at varying concentrations. The diffusivity of the SIPN polymer hydrogel was estimated by the ‘Theory of Elastomer’ to get an insight into process of Potassium and Chlorine ion transport through the SIPN.

Wheat gluten (WG) is reactively blended with a macromolecular cross-linker, polyethylene-alt- maleic anhydride (PEMA), to simultaneously improve strength, stiffness, strain, and reduce water absorption for the first time. FTIR illustrates the cross-linking reaction. An increase in Tg measured by DSC and a decrease in protein extractability measured by SE-HPLC demonstrates an increase in cross-linking as PEMA content increases. The modified WG is thermo-molded into solid bars and tested for flexural properties. The flexural testing results indicate that the maximum strain and stress of the modified WG can be improved by as much as 95% and 120%, respectively. Addition of PEMA to WG lowers the water absorption by as much as a factor of 4 at the same time as improving the mechanical properties. The results are consistent with a single phase, intermolecular, cross-linked morphology. The improvements attained make these blends approach the properties of polystyrene and aerospace grade epoxies.

Brown grease is a common waste product responsible for many sewer overflows and illnesses, and it contains useful free fatty acids and other hydrocarbon-like molecules. This work demonstrates the potential to transform nearly 100% of the brown grease into biodiesel, synthesis gas and bio-oil for use as biofuel or for power generation. A solid acid catalyst was synthesized with excellent activity for esterification of the free fatty acids and relatively high activity for transesterification of triglycerides, which make up the oil phase of the brown grease. The catalyst is synthesized using a tri-block copolymer template that leads to mesopores with diameters narrowly centered at 11.1 nm. Residual solids, which make up roughly 10% of the brown grease, were found by elemental analysis to be a hydrogen rich feedstock, with H/C eff ratio greater than wood or sugar. Preliminary gasification and pyrolysis experiments illustrate nearly 100% conversion of the residual solids. Fast pyrolysis in a drop tube furnace at 600 °C produced oil consisting predominantly of long chain hydrocarbons.

We present a novel twin cell model to evaluate the effect of structure and composition on glass transition of Zr–Ti–Cu–Ni and Zr–Al–Cu–Ni quaternary thin film metallic glasses. Starting from Navier–Stokes equation the statistical average velocity was evaluated under the condition of ensemble equality. This was used to compute the diffusion lengths and the diffusion coefficients as a function of temperature, where from the glass transition temperature was estimated. An increasing Ni concentration was seen to lower the glass transition by up to 200 K, a trend substantiated by Johnson's studies on the lowering of Laves phase with increasing Ni concentration.

A sheet nano-porous membrane (PAN), nominal pore size 10 nm is experimentally employed in order to treat the oily wastewater in a desalter plant. Response surface methodology (RSM) based on Box–Behnken method is used to design the experiment and analyze five operating parameters including; trans-membrane pressure (TMP), salt concentration, cross flow velocity (CFV), pH and feed temperature. The maximum permeation flux of 180.1 L/m 2 h is identified by RSM at feed temperature of 45 °C, TMP of 4 bar, CFV of 1.3 m/s, pH of 10 and salt concentration of 11.2 g/L. The results show that nano-porous membrane is efficient for treatment of petroleum refinery waste water, so that total suspended solids, total dissolved solids, oil and grease content and chemical and biochemical oxygen demand are increased to 100%, 44.4%, 99.9%, 80.3% and 76.9%, respectively. The treated water by the proposed method meets the process and industrial water quality requirements for the discharge to the environment or reuse as agricultural water.

Accurate and fast detection of ammonia gas is a highly desirable requisite in environmental gas analysis, the automotive industry, the chemical industry and for medical applications. In this study a cost effective and portable electrochemical ammonia (NH 3 ) gas sensor is reported. The sensor was based on polyaniline (PANI) nanofibres employing the techniques of electrical impedance spectroscopy with frequency response analysis and amperometry. PANI is well known for its interaction with ammonia gas. This conducting polymer (PANI) of the semi-flexible rod polymer family, is unique due to its easy synthesis method, environmental stability, and simple doping/dedoping chemistry. PANI was synthesized and characterized by SEM, FTIR, XRD and AFM studies. The experimental data were used to explain, characterize and standardize the changes, upon exposure to ammonia gas, in the resistive and capacitative components set up in the PANI electrochemical cell. This nondestructive chemical-gas sensor was characterized by high sensitivity, a wide range of measured concentrations (0–20 ppm) in case of EIS and (2.5–20 ppm) in case of amperometry, reliability and reproducibility of the sensing data.

We report here an efficient mesoporous polymeric solid acid catalyst (p-PDVB-SO3H) with superhydrophobic–oleophilic properties synthesized from copolymerization of divinylbenzene (DVB) with sodium p-styrene sulfonate under solvothermal conditions. N2 isotherm showed that p-PDVB-SO3H has large BET surface area and uniform mesopore. Contact angle tests showed that p-PDVB-SO3H exhibits superhydrophobic–oleophilic property for triolein and methanol, which results in its good miscibility and high exposition degree of active sites for various organic reactants. Catalytic tests showed that p-PDVB-SO3H has much better catalytic activities and recyclability toward transesterification to biodiesel than those of H-form mesoporous ZMS-5 zeolite, carbon solid acid and commercially acidic resin of Amberlyst 15, which will be very important for its wide applications for biodiesel production in industry. Superhydrophobic–oleophilic mesoporous solid acid of p-PDVB-SO3H exhibits very good wettability for methanol and plants oil, further leading to its high exposition degree of active sites, which results in its excellent catalytic activity toward transesterification to biodiesel.

This work reports a novel two dimensional approach to the theoretical elucidation of glass transition of the Pd–Cu–Ni–P thin film system, for the first time, with the existing liquid state theories in the realm of transport properties. It is found that this particular combination of metals set a characteristic trend in variation of glass transition temperature irrespective of their compositional ratio. This investigation on these 2D systems uses pentagonal symmetries of variable orientations and justifies their appropriateness in the class of Pd–Cu–Ni–P system. The data obtained are congruent with experimentally measured glass transition temperatures within a maximum of ± 10% variation and underscore the significance of Pd as a glass former.

Aberrant dopamine release in the prefrontal cortex (PFC) is believed to underlie schizophrenia, but the mechanistic pathway through which a widely used antipsychotic, clozapine (Clz), evokes neurotransmitter-releasing electrical stimulation is unclear. We analyzed Clz-evoked regulation of neuronal activity in the PFC by stimulating axons in layers IV and V and recording the electrical effect in the post-synaptic pyramidal cells of layers II and III. We observed a Clz-evoked increase in population spike (PS), which was mediated by serotonin 1A receptor (5-HT(1A)-R), phospholipase Cβ, and Ca(2+)/calmodulin-dependent protein kinase II (CaMKII). Immunoblotting demonstrated that the Clz-activation of CaMKII was 5-HT(1A)-R-mediated. Intriguingly, the NMDA receptor (NMDA-R) antagonist (±)2-amino-5-phosphonovaleric acid (APV) eliminated the Clz-mediated increase in PS, suggesting that the 5-HT(1A)-R, NMDA-R and CaMKII form a synergistic triad, which boosts excitatory post-synaptic potential (EPSP), thereby enhancing PS. In corroboration, Clz as well as NMDA augmented field EPSP (fEPSP), and WAY100635 (a 5-HT(1A)-R antagonist), APV, and a CaMKII inhibitor eliminated this increase. As previously shown, CaMKII binds to the NMDA-R 2B (NR2B) subunit to become constitutively active, thereby inducing α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) receptor recruitment to the post-synaptic membrane and an increase in fEPSP. Co-immunoprecipitation demonstrated that Clz potentiates interactions among CaMKII, NR2B, and 5-HT(1A)-R, possibly in the membrane rafts of the post-synaptic density (PSD), because pretreatment with methyl-β-cyclodextrin (MCD), an agent that disrupts rafts, inhibited both co-immunoprecipitation as well as fEPSP. In summary, Clz functions in the PFC by orchestrating a synergism among 5-HT(1A)-R, CaMKII, and NMDA-R, which augments excitability in the PFC neurons of layers II/III.

The study describes iontophoretic release of Salicylic acid and Potassium Salt of Acetyl Salicylic acid which is commonly known as the analgesic and thromboxane prostaglandins inhibitor, Disprin, from hydrogel patches based on Poly(vinyl alcohol), Poly (vinyl acetate–co–crotonic acid) & Poly (vinyl pyrrolidone). The experiment utilized a modified Franz cell for iontophoresis with a brine filled receptor chamber and employed Visible Colorimetry as the technique for estimation. It can be concluded that the composition of the hydrogel matrix has a direct bearing on the diffusion of the drugs. The hydrogel composition determines the extent of crosslinking, crystallinity, availability of hydrophilic groups, polymer—water interaction and hence the water take up. The ability of a drug delivery hydrogel system to control solute transport and release depends highly on the water content and water movement within the polymeric structure. The study was carried out keeping in view the eventual development of an alternative electrically controlled delivery mechanism of drugs without adverse gastrointestinal systemic ramifications.

For the first time cesium diffusivity in aqueous solutions of rubidium chloride is being reported here in the concentration range from 0.001 to 4.00 mol⋅dm−3. The measurement use a radioactive tracer technique employing a sliding cell mechanism. These diffusivity values were utilized to understand the transport mechanism of Cs ion in the RbCl–H2O system using the Onsager-Gosting-Harned equation and the extended Debye-Huckel equation. The observed deviation between the theoretical and experimental diffusivities are explained by introducing the concept of Field-Dielectric-Gradient forces and energies that exist around an ion, which takes care of the finite size of the ion, ion-water interaction and the ion-ion interaction in a continuum basis.

1,3-propanediol (1,3-PD) was produced with a robust fermentation process using waste glycerol feedstock from biodiesel production and a soil-based bacterial inoculum. An iterative inoculation method was developed to achieve independence from soil and selectively breed bacterial populations capable of glycerol metabolism to 1,3-PD. The inoculum showed high resistance to impurities in the feedstock. 1,3-PD selectivity and yield in batch fermentations was optimized by appropriate nutrient compositions and pH control. The batch yield of 1,3-PD was maximized to ~0.7 mol/mol for industrial glycerol which was higher than that for pure glycerin. 16S rDNA sequencing results show a systematic selective enrichment of 1,3-PD producing bacteria with iterative inoculation and subsequent process control. A statistical design of experiments was carried out on industrial glycerol batches to optimize conditions, which were used to run two continuous flow stirred-tank reactor (CSTR) experiments over a period of >500 h each. A detailed analysis of steady states at three dilution rates is presented. Enhanced specific 1,3-PD productivity was observed with faster dilution rates due to lower levels of solvent degeneration. 1,3-PD productivity, specific productivity, and yield of 1.1 g/l hr, 1.5 g/g hr, and 0.6 mol/mol of glycerol were obtained at a dilution rate of 0.1 h−1which is bettered only by pure strains in pure glycerin feeds.

The effects of acrobatic exercise and magnetic stimulation (MS) in mice applied either separately or in combination while on recovery after spinal cord injury have been investigated. This progress has been compared in six groups of animals. The first two groups consisted of non-injured and injured animals, respectively, which were not exposed to any treatment. The third group included injured animals that participated in an acrobatic exercise and were exposed to MS applied at the frequency of 1 Hz. The animals in the fourth group were exposed to the MS (1 Hz) only, without performing any acrobatic exercises. While the mice in the fifth group participated in the acrobatic exercise and were exposed to MS at 15 Hz, the animals in group six received an acrobatic exercise without exposure to MS. The effects of the treatment were evaluated with the Basso Mouse Scale, the Horizontal Ladder Scale, and the Abnormal Posture Scale. While all groups showed improvement at the end of the study period, the animals that received exercise combined with 1 Hz MS demonstrated the best functional improvement. The animals exposed to the MS applied at a frequency of 15 Hz combined with acrobatic exercise, and those animals that were engaged in exercise and were not exposed to the MS, performed the worst. The area of the spared white matter at the lesion center correlated well with functional recovery and was greatest in the animals that received MS (1 Hz) combined with exercise.