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Objectives Almond has been listed in the low FODMAPs (Fermentable Oligo-, Di-, Mono saccharides And Polyols) and is recommended for infant diarrhea and gastrointestinal problem in Iranian folk medicine. In this work, sachet of almond has been designed, formulated and is studied on the clinical symptoms of diarrhea prominent irritable bowel syndrome (IBS-D). Design: almond was standardized on the basis of total protein and carbohydrate content. A sachet of almond and wheat flour (placebo) was formulated and their physicochemical characteristics were investigated. Intervention: In a double blind randomized trial, fifty IBS-D patients were randomly enrolled into the almond and placebo groups, ranked in respect to the severity of symptoms to mild-moderate and severe disease. The patients received almond or placebo sachet (40 g/day,20 days) respectively. Main outcome measure: Patients were assessed for bowel habit, pain severity and frequency and bloating and data was recorded in a data collecting form. Results: The results showed that none of the primary outcomes of the disease is improved in the patients treated with almond. The bowel movement and severity of the pain was significantly increased in the almond treated patients compared to the placebo and baseline (p Conclusion Almond contains high content of oligo-fructan which in high intake might result in a large amount of fermentable carbohydrates that can exacerbate the symptoms of the disease. So, despite the almond inclusion in the low-FODMAPs, the amount of almond intake is a determining factor and here we have controversial results for almond intake in patients with IBS. Mental health and physical activity of patients are also involved in the disease.

High theoretical capacity and lowest electrochemical potential make lithium metal anode the most suitable anode material for lithium-ion batteries (LIBs). However, Lithium dendrite growth on lithium metal anode hinders proper discharge capacity and practical cycle life of LIBs. It dues to high lithium-ion flux in the solid electrolyte interphase (SEI) layer versus low diffusion in anode structure. Herein, we employ argon and oxygen plasma to modify commercial polypropylene separator surface to negatively functionalize the separator surface and discuss the influence of increasing surface negative charge on lithium dendrite growth and formation of SEI layer. Comparing electrochemical and battery performance of unmodified and plasma modified separators demonstrates, increased negative surface charge prevents lithium dendrite growth and makes a uniform and thin SEI layer due to lowering lithium-ion flux in the SEI layer. More precisely, we conduct that coulombic interaction between plasma modified separator's surface and electrolyte's cations (anions) can regulate lithium-ion flux in the SEI layer, preventing lithium dendrite growth and making thin homogeneous SEI layer on lithium metal anode structure.

One-piece bearing is the latest type of total disc replacement (TDR) design that is used for the treatment of lumbar degenerative disc disease (DDD). Due to the unique properties of the shape memory polymers (SMPs), such as self-healing, shape-memory, adhesion control, and self-deployable ability, they may be a good candidate for the core of such a design. The purpose of the present study is to use an analytical method combined with a numerical analysis (finite element analysis (FEA)) to determine the mechanical responses of an SMP intervertebral disc (IVD) model, under pure torsion (axial rotation) and pure compression, two loading conditions to which natural intervertebral discs (IVDs) are subjected in vivo. We considered the SMP IVD model to be positioned at L4-L5 because most cases of lumbar DDD are reported at this segment. For the analytical method, an appropriate constitutive equation for an SMP was determined and, then, an analytical solution for the torsional response of a circular SMP IVD model, in a full cycle of stress-free strain recovery, was derived. The developed equations were implemented in finite element modeling to determine responses of the IVD disc model under pure torsion. Additionally, responses of the SMC IVD model, under a compressive load, and different conditions were determined. The analytical and FEA results were compared to experimental results give in the literature for intact lumbar spine segments as the core in a one-piece lumbar TDR. Based on this study, we suggest that SMPs can be used for TDR, as they are strong enough to bear the torsional and compressive loads that IVD is subjected through its life.

In the present work, the effect of plasma power and oxygen flow rate on methane conversion and methanol selectivity in a DBD reactor. The results indicate that increasing power at constant gas flow rate leads to enhancing methane conversion relatively linearly, while methanol selectivity is improved initially and then declines. Moreover, increasing oxygen flow rate from 40 sccm to 75 sccm at a constant methane flow rate of 100 sccm leads to rise in methane conversion and methanol selectivity. The results show that formation of copper oxide on electrode surface can be very effective in achieving high methanol yields.

The focus of this study is to explore the feasibility of using basalt fibers (BF) as a potential sustainable alternative to glass fibers (GF) in sheet molding compounds (SMC) to reduce the weight and cost of conventional GF SMC. The interfacial interactions for BF/epoxy and GF/epoxy composites were assessed through single fiber fragmentation tests. The mechanical properties, including tensile and flexural modulus and strength, impact strength and thermomechanical properties for 25 wt% BF/epoxy composites made using SMC were determined and directly compared to 25 wt% GF/epoxy SMC composites. As indicated by the single fiber fragmentation tests, the two composites had similar interfacial shear strength (IFSS) and consequently similar adhesion at the fiber-epoxy interface. In addition, no distinguishable differences were found in the curing behavior of the two SMC composites. The storage modulus of the 25 wt% BF/epoxy composites was found to be higher than that of 25GF/epoxy in the glassy state. Moreover, the average tensile and flexural properties (both absolute and specific values) of the 25 wt% BF/epoxy SMC composites were higher or at least equal to those of 25 wt% GF/epoxy SMC composites. No difference in the impact strength of the two composites was recorded considering the statistical variation. In general, BF/epoxy SMC composites showed better or equal mechanical performance compared to GF/epoxy SMC composites suggesting that BF may be an alternative to GF with the potential to lead to lower cost SMC composites.

A scalable technique was introduced to produce high volume lightweight composites using sheet molding compound (SMC) manufacturing method by replacing 10 wt% glass fibers (GF) with a small amount of cellulose nanocrystals (CNC). The incorporation of 1 and 1.5 wt% CNC by dispersing in the epoxy matrix of short GF/epoxy SMC composites with 25 wt% GF content (25GF/CNC-epoxy) produced 7.5% lighter composites with the same tensile and flexural properties of 35GF/epoxy composites with no CNC. The addition of 1 wt% CNC in 25GF/CNC-epoxy SMC composites resulted in increases of 15% in elastic modulus, 11% in flexural modulus and 14% in flexural strength, reaching the corresponding properties of 35GF/epoxy SMC composites. Moreover, it was found that although addition of CNC did not alter the impact energy, removing 10 wt% GF resulted in reduction of impact energy.

The mechanical properties of short glass fiber/epoxy composites containing cellulose nanocrystals (CNC) made using sheet molding compound (SMC) manufacturing method as well as the rheological and thermomechanical properties of the CNC-epoxy composites were investigated as a function of the CNC content. CNC up to 1.4 wt% were dispersed in the epoxy to produce the resin for SMC production. The addition of CNC in the resin increased its viscosity and slightly reduced the heat of reaction during the polymerization without altering the curing time and temperature and the effective pot life of the resin. The incorporation of 0.9 wt% CNC in the SMC composite resulted in increases in elastic modulus and tensile strength by ∼25% and ∼30% and in flexural modulus and strength by ∼44% and ∼33% respectively. Concentrations of CNC up to 0.9 wt% in the SMC composite did not alter the impact energy.

This study explores the use of carbon fiber (CF) prepreg trim waste to manufacture lightweight, high performance and low cost CF composites using sheet molding compound (SMC) technology. First, the modifications of a typical SMC and a flow study to determine the charge in size and mass of the sheets are determined. Then, the effect of the age of the prepreg tapes, aspect ratio of cut chips and pressure during compression molding on the tensile and impact properties of the composites is determined and these properties are compares with those of typical SMC composites. It is concluded that (i) the standard SMC production line needs to be modified in order to successfully convert CF tapes into sheets and (ii) the produced CF composites can meet the high stiffness and acceptable strength for not strength-critical applications without the need to store the prepreg trim waste in controlled conditions.

This study was undertaken to synthesize Fe2O3-doped TiO2 nanoparticles using a long tail ionic liquid-assisted sol-gel method (IL-Fe2O3/TiO2) in order to photodegrade bisphenol A (BPA). Physicochemical properties of the synthesized photocatalysis were characterized through FTIR, FESEM-EDX, XRD, and DRS. The modeling and optimization of the photodegradation of BPA by IL/ Fe2O3-TiO2 were conducted with response surface methodology (RSM) by considering the central composite design (CCD). The results revealed that the 1-octadecyl-3-methylimidazolium bromide ([OMD]Br) ionic liquid, in combination with ferric oxide dopant, created low aggregated nanocomposites with a uniform and tiny grain size. 2.4 eV. bandgap energy was computed for IL-Fe2O3/TiO2. The quadratic model obtained from the ANOVA results of photodegradation processes. A BPA removal efficiency of 90.33 % was acquired under optimal conditions (IL-Fe2O3/TiO2 loading dose = 0.75 g/L, pH = 9, initial BPA concentration = 10 mg/L, and UV irradiation time = 97.5 min). The results indicated that the photodegradation of BPA was mostly affected by the variables of time, pH, and initial BPA concentration, respectively. Only the second term of the IL-Fe2O3/TiO2 loading dose as a variable had a significant effect on the efficiency of the process. The Langmuir–Hinshelwood model was selected to investigate photodegradation kinetics.

Quasi-static damage in multidirectional polymer composite (PMC) laminates developing during manufacturing and quasi-static loading degrades the modulus and strength. A model to predict simultaneous evolution of quasi-static transverse cracking in multiple plies and its effect on modulus of multidirectional PMCs is presented. A 3-D variational analysis formulating the in-plane and out-of-plane stresses of the plies in occurrence of multiple cracking has been developed to work within a lamination theory-based model framework. The stress state in the plies is determined using the lamination theory during an incremental change in loading. The strain energy, determined using this stress state, is compared to strain energy-based failure criteria to determine if a ply cracks after the increment. If crack is predicted, crack density of the ply is updated and the variational analysis is used to determine the perturbation in ply stresses due to cracking. The new stress state is used to determine the laminate modulus after cracking and the ply stresses for the next increment. This procedure is repeated to determine the crack evolution and modulus until reaching the desired load. Model predictions compare very well with experimental results for a [± θ m /90 n ] s laminate at two elevated test temperatures of 80 °C and 180 °C.

A model to predict time-dependent evolution of simultaneous transverse cracking developed in multiple plies during creep loading and its effects on creep of multidirectional polymer matrix composite laminates is presented. The stress states in the intact regions of the plies are determined using the lamination theory during an incremental change in time. The stored elastic energy, determined using this stress state, is compared with a critical stored elastic energy value for damage to determine if a ply would fracture after the increment. If fracture is predicted, variational analysis is used to determine the perturbation in ply stresses due to cracking. This procedure is repeated to determine the crack evolution and creep strain. Model predictions compared well with experimental results for a [±θm/90n]s laminate.

3D printed polymer parts remain too low in mechanical performance that inhibits their industrial applications. We introduce a novel and scalable technique to enhance the strength of 3D printed polymer parts. We incorporate cellulose nanocrystals (CNCs) between adjacent layers of polymer with the aid of an atomization process integrated within a fused deposition modeling printer to spray aqueous suspensions of CNC during the printing process. CNCs act as nano-stitches between the polymer layers and thus improve the interlayer adhesion and ultimate strength of the printed parts. We show that spraying aqueous suspension of CNC with 0.5–1 wt% concentrations increase the interlayer strength of acrylonitrile butadiene styrene (ABS) parts by 44%, tensile strength by 33%, tensile modulus by 20% and the toughness by 33% in both longitudinal and transverse directions. Increasing CNC concentration above 1 wt%, however, results in CNC agglomerates between layers, which negatively affects the interlayer adhesion and reduces the ultimate strength. Non-toxicity of CNC and water and hydrophilicity of CNC leverage the scalability of this method.

An experimental study (Birur et al., 2006 [1]) on time-dependent evolution of various damage modes under constant load was extended; specifically, time-dependent evolution and influence of transverse cracks, in ±45° and 90° plies, on the creep of [±45/902]S multidirectional laminate of a polymer composite (Hexcel F263-7/Toho G30-500) was studied and modeled. The damage evolved with time in both ply groups sequentially and/or simultaneously depending on the test conditions. For the latter case, the two ply groups influenced each other’s damage evolution. The creep of the laminate was due to both the viscoelasticity of the plies and the time-dependent damage. A damaged ply was modeled using an equivalent undamaged ply with an apparent compliance, which was determined as a function of time-dependent transverse crack density. This was used along with a model frame work, based on lamination theory, to predict the creep compliance of the [±45/902]S laminate. The model predictions compared well with experimental results.