The aim of this study was to compare the investigations of various contents of egg white protein (2.0%-8.0%, EWP), microbial transglutaminase (0.1%-0.4%, MTGase), and konjac glucomannan (0.5%-2.0%, KGM) on the gelling properties and rheological behavior of Trachypenaeus Curvirostris shrimp surimi gel (SSG), and assessed the modification mechanisms through the analysis of structure characteristics. The findings suggested that all modified SSG samples (expect SSG-KGM2.0% ) had the higher gelling properties and the denser network structure than those of unmodified SSG. Meanwhile, EWP could give SSG a better appearance than MTGase and KGM. Rheological results showed that SSG-EWP6% and SSG-KGM1.0% had the highest G' and G″, demonstrating that the formation of higher levels of elasticity and hardness. All modifications could increase gelation rates of SSG along with the reduction of G″ during the degeneration of protein. According to the FTIR results, three modification methods changed SSG protein conformation with the increasing α-helix and β-sheet contents and the decreasing of random coil content. LF-NMR results indicated that more free water could be transformed into immobilized water in the modified SSG gels, which contributed to improve the gelling properties. Furthermore, molecular forces showed that EWP and KGM could further increase the hydrogen bonds and hydrophobic interaction in SSG gels, while MTGase could induce the formation of more disulfide bonds. Thus, compared with another two modifications, EWP modified SSG gels showed the highest gelling properties.
Generally, a base isolator is made up of alternate layers of steel and rubber. The idea of adopting magnetoreological elastomers (MREs) in base isolator systems was introduced in the past few years in order to improve the efficiency of base isolator systems. The article provides information on the mechanical corresponding to different carbon black loading loadings of 20 parts per hundred rubber (pphr), 40 pphr and 60 pphr in natural rubber compound. The mechanical dataset described the data from tensile, hardness and rebound test.
This work focuses on the fabrication of hybrid bio-composites using green epoxy as the matrix material, hemp (H) and sisal (S) fibre mats as the reinforcements. The hybrid composite with sisal/hemp fibres were fabricated by cost effective hand lay-up technique, followed by hot press with different stacking sequences. Static properties of the composites such as tensile, compressive, inter-laminar shear strengths (ILSS) and hardness were examined. The physical properties such as density, void content, water absorption and thickness swelling were also analyzed. The experimental results indicate that hybrid composites exhibited minor variation in tensile strength when the stacking sequence was altered. The hybrid composite with the intercalated arrangement (HSHS) exhibited the highest tensile modulus when compared with the other hybrid counterparts. Hybrid composites (SHHS and HSSH) offered 40% higher values of compressive strength than the other layering arrangements. HHHH sample exhibited the highest ILSS value of 4.08 MPa. Typical failure characteristics of the short beam test such as inter-laminar shear cracks in the transverse direction, micro-buckling and fibre rupture were also observed.
Adzuki bean is high in protein and fiber with a potential to be used as meat extender and fat replacer in the meat product. Replacement of both the corn flour and fat with different percentages of adzuki beans flour (ABF) has successfully produced acceptable reduced fat meatballs. Meatballs with 100% (w/w) ABF replacement exhibited highest cooking yield and higher moisture content compared to meatballs without the flour, which indicates its ability to bind water. Increasing the ABF content also increased the hardness and chewiness of the meatballs, whilst decreasing their lightness and yellowness. Replacing the corn flour and fat contents with ABF has obviously decreased the fat and calorie contents of the meatballs, yet their protein and carbohydrate contents remained the same compared to control. The sensory test revealed that meatball samples with 25% (w/w) and 50% (w/w) ABF showed no significant difference compared to control but received highest overall acceptability among the panelists. This indicates that replacement of corn flour and fat with ABF especially at 50% (w/w) in the production of reduced fat meatballs resulted with better physicochemical properties and acceptable sensory compared to original meatballs.
PVD process as a thin film coating method is highly applicable for both metallic and ceramic materials, which is faced with the necessity of choosing the correct parameters to achieve optimal results. In the present study, a GEP-based model for the first time was proposed as a safe and accurate method to predict the adhesion strength and hardness of the Nb PVD coated aimed at growing the mixed oxide nanotubular arrays on Ti67. Here, the training and testing analysis were executed for both adhesion strength and hardness. The optimum parameter combination for the scratch adhesion strength and micro hardness was determined by the maximum mean S/N ratio, which was 350W, 20 sccm, and a DC bias of 90V. Results showed that the values calculated in the training and testing in GEP model were very close to the actual experiments designed by Taguchi. The as-sputtered Nb coating with highest adhesion strength and microhardness was electrochemically anodized at 20V for 4h. From the FESEM images and EDS results of the annealed sample, a thick layer of bone-like apatite was formed on the sample surface after soaking in SBF for 10 days, which can be connected to the development of a highly ordered nanotube arrays. This novel approach provides an outline for the future design of nanostructured coatings for a wide range of applications.
In this study, lignin has been extracted from oil palm empty fruit bunch (EFB) fibers via an organosolv process. The organosolv lignin obtained was defined by the presence of hydroxyl-containing molecules, such as guaiacyl and syringyl, and by the presence of phenolic molecules in lignin. Subsequently, the extracted organosolv lignin and graphene nanoplatelets (GNP) were utilized as filler and reinforcement in photo-curable polyurethane (PU), which is used in stereolithography 3D printing. The compatibility as well as the characteristic and structural changes of the composite were identified through the mechanical properties of the 3D-printed composites. Furthermore, the tensile strength of the composited lignin and graphene shows significant improvement as high as 27%. The hardness of the photo-curable PU composites measured by nanoindentation exhibited an enormous improvement for 0.6% of lignin-graphene at 92.49 MPa with 238% increment when compared with unmodified PU.
Semisolid metal (SSM) processing or thixoforming is widely known as a technology that involves the formation of metal alloys between solidus and liquidus temperatures. For the procedure to operate successfully, the microstructure of the starting material must consist of solid near-globular grains surrounded by a liquid matrix and a wide solidus-to-liquidus transition area. Currently, this process is industrially successful, generating a variety of products with high quality parts in various industrial sectors. Throughout the years since its inception, a number of technologies to produce the appropriate globular microstructure have been developed and applied worldwide. The main aim of this paper is to classify the presently available SSM technologies and present a comprehensive review of the potential mechanisms that lead to microstructural alterations during the preparation of feedstock materials for SSM processing.
In this work, the Sandvik uncoated carbide insert, CNGG 120408-SGF-H13A was used as a cutting tool in high-speed turning of titanium alloy Ti-6A1-4V EH (extra-low interstitial) with hardness of 32 HRC. Wear is one of the problems that cannot be avoided in machining process. Therefore, the objective of this paper was to investigate tool-wear behavior of various cutting-speed values (high-speed range) on the tool life of the cutting tools, especially in finishing titanium alloy. The experiments were performed under flooded coolant condition using water-based mineral-oil. The cutting speeds employed were 120, 170 and 220 mlmin. The feed rate was constant at 02 mm/rev and the depth of cut was 0.4 mm. Based on the results, the highest cutting speed of 220 m/min caused the highest wear rate. By linking the machine operations and the tool life curves obtained using flank wear data, the wear behavior of uncoated carbide was described.
Austempering is one of the trendiest heat treatment processes to promote the strength and toughness of ductile iron. However, such practice is complex because it involves using aqueous solutions as quenchant (salt bath solution). This study was conducted to analyse the heat treatment of the combination processes of annealing-austenitising and evaluate the correlation between microstructure constituent and hardness of the ductile iron. Ductile iron samples in form of double cylinder was produced by conventional CO2 sand casting method. The new heat treatment process was started by annealed at 873 K for 1.8 ks before being oil quenched. Subsequently, the samples were austenitised at austenitising temperatures 1123 K, 1173 K and 1223 K for 3.6 ks respectively before being immediately oil quenched to room temperature. A series of microstructure analysis tests, including optical microscopy and X-ray diffraction (XRD) was applied. Vickers microhardness tester was used to measure the hardness for each microstructure constituent. The results showed that ductile iron matrix transforms to martensitic during heat treatment of annealing-austenitising combination processes, which in turn contributes to increasing microhardness of martensite and the bulk hardness of ductile iron.
The fundamental pattern of chewing induced by the network of neurons called central pattern generator has been reported
to be modified by the information arising from the various oro-facial sensory receptors including muscle spindles of jaw
closing muscles. The cell bodies of primary afferent neurons from these muscle spindles lie in mesencephalic trigeminal
nucleus (MTN) in the brainstem. The aim of the study was to understand whether muscle spindles from jaw-closing
muscles play any role in hard food chewing. Single neuronal discharge of muscle spindle afferents was recorded from the
MTN simultaneous with jaw-movement and electromyograpic (EMG) activities of the left masseter (jaw-closing) muscle
during chewing soft and hard foods (apple and pellet) in awake rabbits. Ten consecutive chewing cycles were taken for
analysis. Discharge of nineteen muscle spindles from seven rabbits was successfully recorded. Muscle-spindle discharge
was significantly higher during the closing phase of jaw-movement for the hard food chewing than for the soft food. The
jaw-closing muscle EMG activity was significantly higher during hard food chewing compared to soft food. The spindle
discharge was higher when the masseter muscle activity was greater for chewing hard food. Significant positive (r=0.822,
p=<0.001) correlation was found between the difference of muscle activity between apple and pellet and the difference
of spindle discharge between apple and pellet. Above findings suggest that the increase of spindle discharge during
hard food chewing may play a role for facilitating jaw-closing muscle activities and thereby provides servo-assistance
to jaw-closing muscles to compensate the hardness of food.
There are a number of drawbacks to incorporating large concentrations of barium sulfate (BaSO4) as the radiopacifier in PMMA-based bone cements for percutaneous vertebroplasty. These include adverse effects on injectability, viscosity profile, setting time, mechanical properties of the cement and bone resorption. We have synthesized a novel cement that is designed to address some of these drawbacks. Its powder includes PMMA microspheres in which gold particles are embedded and its monomer is the same as that used in commercial cements for vertebroplasty. In comparison to one such commercial cement brand, VertaPlex™, the new cement has longer doughing time, longer injection time, higher compressive strength, higher compressive modulus, and is superior in terms of cytotoxicity. For augmentation of fractured fresh-frozen cadaveric vertebral bodies (T6-L5) using simulated vertebroplasty, results for compressive strength and compressive stiffness of the construct and the percentage of the volume of the vertebral body filled by the cement were comparable for the two cements although the radiopacity of the new cement was significantly lower than that for VertaPlex™. The present results indicate that the new cement warrants further study.
This study was carried out to investigate physicochemical properties of different concentrations (0.1%, 0.3%, and 0.5%) of red ginseng hydrolyzates (RGH)- or red ginseng extract (RGE)-added Asiago cheeses (AC) during ripening at 14°C for 4 months. The moisture content significantly increased with increasing concentrations of both RGH- and RGE- added AC (p<0.05). While RGHAC and RGEAC were more yellow and darker with increasing concentrations than that of control (p<0.05), the color was not influenced from the hydrolysis. In texture analysis, hardness, cohesiveness, and chewiness of RGHAC and RGEAC significantly decreased compared to the control during the ripening (p<0.05). In sensory analysis, bitterness and ginseng flavor and taste scores increased significantly with increasing the concentrations of RGH and RGE during ripening (p<0.05). In conclusion, the addition of RGH and RGE into cheese slightly influenced the properties of Asiago cheese, and similarities were observed between RGHAC and RGEAC. Thus, the lower concentrations (0.1% to 0.3%) of RGH and RGE added to AC were preferred for color, texture, and sensory during the ripening, therefore, these cheeses would be worth developing commercially.
Diacylglycerol (DAG), which has health-enhancing properties, is sometimes added to bakery shortening to produce baked products with enhanced physical functionality. Nevertheless, the quantity present is often too little to exert any positive healthful effects. This research aimed to produce bakery shortenings containing significant amounts of palm diacyglycerol (PDG). Physicochemical, textural and viscoelastic properties of the PDG bakery shortenings during 3 months storage were evaluated and compared with those of commercial bakery shortening (CS).
This study (1) compared the curing-light intensity with various barrier infection-control methods used to prevent cross contamination, (2) compared the Knoop hardness value of cured composite resin when various barrier control methods were used, and (3) correlated the hardness of the composite resin with the light-intensity output when different infection-control methods were used. The light-cure unit tips were covered with barriers, such as cellophane wrap, plastic gloves, Steri-shields, and finger cots. The control group had no barrier. Composite resins were then cured for each of the five groups, and their Knoop hardness values recorded. The results showed that there was significant statistical difference in the light-intensity output among the five groups. However, there was no significant statistical difference in the Knoop hardness values among any of the groups. There was also no correlation between the Knoop hardness value of the composite resin with the light-intensity output and the different infection-control methods. Therefore, any of the five infection-control methods could be used as barriers for preventing cross-contamination of the light-cure unit tip, for the light-intensity output for all five groups exceeded the recommended value of 300 W/m2. However, to allow a greater margin of error in clinical situations, the authors recommend that the plastic glove or the cellophane wrap be used to wrap the light-cure tip, since these barriers allowed the highest light-intensity output.
This research aims to test four new polymers for their stability under high salinity/high hardness conditions for their possible use in polymer flooding to improve oil recovery from hydrocarbon reservoirs. The four sulfonated based polyacrylamide co-polymers were FLOCOMB C7035; SUPERPUSHER SAV55; THERMOASSOCIATIF; and AN132 VHM which are basically sulfonated polyacrylamide copolymers of AM (acrylamide) with AMPS (2-Acrylamido-2-Methylpropane Sulfonate). AN132 VHM has a molecular weight of 9⁻11 million Daltons with 32 mol % degree of sulfonation. SUPERPUSHER SAV55 mainly has about 35 mol % sulfonation degree and a molecular weight of 9⁻11 million Daltons. FLOCOMB C7035, in addition, has undergone post-hydrolysis step to increase polydispersity and molecular weight above 18 million Daltons but it has a sulfonation degree much lower than 32 mol %. THERMOASSOCIATIF has a molecular weight lower than 12 million Daltons and a medium sulfonation degree of around 32 mol %, and also contains LCST (lower critical solution temperature) type block, which is responsible for its thermoassociative characteristics. This paper discusses the rheological behavior of these polymers in aqueous solutions (100⁻4500 ppm) with NaCl (0.1⁻10 wt %) measured at 25 °C. The effect of hardness was investigated by preparing a CaCl₂-NaCl solution of same ionic strength as the 5 wt % of NaCl. In summary, it can be concluded that the rheological behavior of the newly modified co-polymers was in general agreement to the existing polymers, except that THERMOASSOCIATIF polymers showed unique behavior, which could possibly make them a better candidate for enhanced oil recovery (EOR) application in high salinity conditions. The other three polymers, on the other hand, are better candidates for EOR applications in reservoirs containing high divalent ions. These results are expected to be helpful in selecting and screening the polymers for an EOR application.
In the current research, osmotic dehydration of red pitaya (Hylocereus polyrhizusis) cubes using sucrose solution at mild temperature (35ºC) was investigated. Sucrose solution (40, 50 and 60% w/w) was employed for osmotic dehydration process. Responses of weight reduction (WR), solid gain (SG), water loss (WL), color (L*, a* and b*) and texture (hardness) were evaluated. It was found that sucrose concentration significantly (p < 0.05) affected the mass transfer terms during osmosis process. The results obtained revealed an increase in yellowness (b*), decrease in lightness (L*) and redness (a*) as the sucrose concentration increased. Furthermore, osmotically dehydrated samples were considerably softer than untreated samples. Increasing of sucrose concentration and dehydration time caused softer tissue of dehydrated product compared with the fresh red pitaya.
This research was conducted to study the effect of reinforcement particles on iron-cobalt (FeCo) composites. The composition of silicon carbide (SiC) was varied from 0 to 20 wt%. The composite was fabricated via powder metallurgy (PM) method, which consists of mixing, compaction and sintering processes. The powder was mixed for 2 hours to obtain uniformity between SiC and Fe-Co matrix and compacted to a cylindrical shape at 250 MPa. Samples were sintered for 2 hours at 900 o C with 10 o C/minute heating rate in argon atmosphere. The influences of reinforcement particle on the sintered samples were characterized in terms of microstructure and hardness testing. The Fe-Co/20wt%SiC composites show highest hardness value.
Characteristics of X-ray transmissions were investigated for epoxy composites filled with 2-10 vol% WO3 loadings using synchrotron X-ray absorption spectroscopy (XAS) at 10-40 keV. The results obtained were used to determine the equivalent X-ray energies for the operating X-ray tube voltages of mammography and radiology machines. The results confirmed the superior attenuation ability of nano-sized WO3-epoxy composites in the energy range of 10-25 keV when compared to their micro-sized counterparts. However, at higher synchrotron radiation energies (i.e., 30-40 keV), the X-ray transmission characteristics were similar with no apparent size effect for both nano-sized and micro-sized WO3-epoxy composites. The equivalent X-ray energies for the operating X-ray tube voltages of the mammography unit (25-49 kV) were in the range of 15-25 keV. Similarly, for a radiology unit operating at 40-60 kV, the equivalent energy range was 25-40 keV, and for operating voltages greater than 60 kV (i.e., 70-100 kV), the equivalent energy was in excess of 40 keV. The mechanical properties of epoxy composites increased initially with an increase in the filler loading but a further increase in the WO3 loading resulted in deterioration of flexural strength, modulus and hardness.
Polymeric materials such as polypropylene (PP), polyethylene (PE) and ethylene propylene diene monomer (EPDM) are widely used as insulators for cable applications. We investigated the effect of alumina trihydrate (ATH) loading on the mechanical properties of PP/EPDM blend. Preliminary study showed that PP/EPDM (60:40) was the optimum composition. ATH filled PP/EPDM composites was prepared by using twin screw extruder. In this study, the tensile properties and hardness of the composites were evaluated. The tensile modulus and hardness increased while elongation at break and tensile strength decreased with increasing ATH content. Scanning electron microscope was used to study the morphology of ATH in PP/EPDM blend.
Soil hardness plays a vital role in evaluating the physical properties of soil structure. With regards to the impact of compaction on practical forest management issues, most report and review forms were available. Thus, the aim of this study was to evaluate the soil condition in riparian forest restoration planted with indigenous species along Kayan Ulu River with special reference to soil hardness. Soil hardness was measured by using Hasegawa-type cone penetrometer from the surface soils to 100 cm depth, with a total of 48 random points for both study sites surveyed; restoration sites planted with Shorea macrophylla in year 1996 and 1998 (SPD96 and SPD98, respectively) for both on and between planting lines. Our findings indicated that, soil hardness in SPD98 was harder as compared to SPD96 at shallow depth presented in one drop penetrability. Likewise, soil penetration resistance on planting line in SPD98 was significantly higher than SPD96 at surface soils (0-20 cm) and subsurface soils (20-40 cm). A high number of strikes and soil penetration resistance indicate that the soils were highly compacted. However, there was no significant difference in term of soil penetration resistance between planting line. In order to avoid effects on tree productivity, it is recommended that in future, the evaluation of soil hardness should be determined during the early establishment for future restoration of riparian ecosystem.