Sufficient Hardness Research Articles

Using capacitive deionisation for inland brackish groundwater desalination in a remote location

In this work, a portable prototype of capacitive deionisation (CDI) unit has been used first time in Wilora, a community in a remote area in Northern Territory, Australia, to remove salt from the brackish groundwater. The CDI unit has demonstrated sufficient salinity and hardness removal ability at the remote brackish water source. It was found that increased flow rate resulted in a decrease of the overall total dissolved solids removal efficiency. However, in terms of energy efficiency, a higher flow rate tended to be favourable. With the current CDI unit configuration and local water conditions, 7L/min is recommended as the optimal operational parameter, with an energy consumption of around 1.89kWh/m3 of treated water. The total water recovery rate was between 75 and 80%. The electrosorption of NaCl onto the CDI cell assembly of 100 pair electrodes follows Langmuir adsorption isotherm and the pseudo-first-order adsorption kinetics. The portable CDI unit proves to be a viable alternative solution to brackish water treatment, especially in communities in remote areas where building a reverse osmosis treatment plant is not practical. The data and results shown in this work can be used as guidance for the on-site operation using this emerging technology.

Primary proton beam line at the J-PARC hadron experimental facility

A brief description of the primary beam line at the hadron experimental facility at the Japan Proton Accelerator Research Complex (J-PARC) is presented. The facility has been constructed in Tokai, Japan, and the first beam was successfully introduced into the experimental hall in January 2009. The facility utilizes a high-intensity proton beam with an energy of 50 GeV and a power of 750 kW and provides various secondary beams such as pions, kaons, and antiprotons for nuclear and particle physics experiments. We have developed beam-line components with sufficient radiation hardness and heat resistance to handle the high-power proton beam.

Effect of basalt addition on tribological performance of FeCrSiB HVOF coatings

Products made of basalt are recently gaining sufficient attention due to depletion of raw materials serving as reinforcement for construction, and wear resistant materials. Basalt has sufficient mechanical strength, high hardness, low density and superior corrosion resistance. Basalt and other minerals are used in thick metal coatings to adjust their thermal expansion to that of the steel substrate. High velocity oxygen fuel (HVOF) sprayed coating method allows to prepare solid basalt-steel composite materials since the melting temperatures of basalt and steel are very close and materials obtained by casting or sintering will have low mechanical properties. The aim of the current work is to study the change in tribological response under erosive, abrasive, reciprocal and continuous sliding conditions when basalt is added to the harder matrix. It was found that the addition of 12 vol % of basalt to the FeCrSiB HVOF sprayed coating is generally unfavourable in tribological conditions due to the brittleness of basalt and its flake shape. The worst relative performance was observed in reciprocal sliding conditions and the best one in mild conditions of continuous sliding. Discussion on the mechanisms of materials performance is based on SEM and EDS results.

Silicon for High-Luminosity Tracking Detectors -Recent RD50 Results

In order to harvest the maximum physics potential of the CERN Large Hadron Collider (LHC), it is foreseen to significantly increase the LHC luminosity by upgrading the LHC towards the HL-LHC (High Luminosity LHC) [1] . Especially the final upgrade (Phase-II Upgrade) foreseen beyond 2020 will mean unprecedented radiation levels. Due to the radiation damage limitations of the silicon sensors presently used, the physics experiments will require new tracking detectors for HL-LHC operation. All-silicon central trackers are being studied in ATLAS, CMS and LHCb, with extremely radiation hard silicon sensors to be used for the innermost layers. Within the CERN RD50 Collaboration, a massive R&D programme is underway across experimental boundaries to develop silicon sensors with sufficient radiation tolerance. One research topic is to gain a deeper understanding of the connection between the macroscopic sensor properties such as radiation-induced increase of leakage current, doping concentration and trapping, and the microscopic properties at the defect level. A further area of activity is the development of advanced sensor types like 3D silicon detectors designed for the extreme radiation levels expected for the vertexing layers at the HL-LHC. Results from irradiation with a mix of different particle types as expected for the sLHC are also given. Recent observations of charge multiplication effects in heavily irradiated detectors at very high bias voltages point towards a new way to achieve sizeable signals after high fluences. Results for several detector technologies and silicon materials at radiation levels corresponding to HL-LHC fluences are presented in this article, demonstrating the availabilty of silicon detectors with sufficient radiation hardness for the different radii of tracking systems in the LHC detector upgrades.

Efficient Fabrication of Ordered Metal Nanodot Array Using Nanoimprint Method with a TiN Thin-Film Mold and Annealing Method

A new efficient fabrication method for an ordered metal nanodot array is developed by coupling nanoimprint method with a TiN thin-film mold and self-assembly of a metal thin-film due to thermal annealing. In this study, in order to develop a thin-film mold which possesses sufficient hardness and durability to use in the nanoimprint, we fabricate a TiN thin-film mold by the nano plastic forming, sputtering and electroplating processes. Using the fabrication method, TiN thin-film molds with different nanoscale surface structures can be developed. Furthermore, we demonstrate that the lattice- and parallel-patterned grooves can be formed on a gold thin-film by the nanoimprint with the developed TiN thin-film molds. It is found that a well-ordered gold nanodot array can be efficiently fabricated on a quartz glass substrate by annealing the gold thin-film formed by the nanoimprint.

FORMULATION AND EVALUATION OF METOCLOPRAMIDE RAPIDLY DISINTEGRATING TABLETS

Metoclopramide an effective antiemetic; acting on the CTZ, blocks apomorphine induced vomiting. Rapidly disintegrating tablets of metoclopramide hydrochloride were prepared by mass extrusion technique using three different superdisintegrants Sodium Starch Glycolate, Avicel Ph 102, L-HPC. Pre-compression parameters and post-compression parameters were evaluated for all the nine formulations. Angle of repose and % compressibility showed good flowability in all the formulations. Weight variation was found within limits and drug content of all the formulations was found in the range of 9.700 mg - 9.925 mg in each tablet. The hardness of all the formulations was almost uniform and possessed good mechanical strength with sufficient hardness. The wetting time in all the formulation was fast. Formulations F3 containing sodium starch glycolate 10% & F6 containing Avicel ph 102 10% tablets disintegrated rapidly to release the drug. In vitro release studies revealed that 96% of drug releases from SSG, MCC (90%), and L-HPC (85%) for all the formulations were within 15 min. Based on above results, three formulations F3, F6, F9 were selected for stability studies these formulations showed not much variation in any parameter even after the period of 30 days, formulations F3, F6, F9 are found to be stable and retained their original properties. Thus, it may be concluded that formulation containing sodium starch glycolate as superdisintegrants is fulfilling all the parameters satisfactorily. It showed excellent in vitro disintegration, in vitro dispersion time, compared to other superdisintegrants. And the rapidly disintegrating tablets can be prepared by mass extrusion technique Â

Effect of crospovidone and hydroxypropyl cellulose on carbamazepine in high-dose tablet formulation

The aim of this study was to develop a high-dose tablet formulation of the poorly soluble carbamazepine (CBZ) with sufficient tablet hardness and immediate drug release. A further aim was to investigate the influence of various commercial CBZ raw materials on the optimized tablet formulation.Materials and methods: Hydroxypropyl cellulose (HPC-SL) was selected as a dry binder and crospovidone (CrosPVP) as a superdisintegrant. A direct compacted tablet formulation of 70% CBZ was optimized by a 32 full factorial design with two input variables, HPC (0–10%) and CrosPVP (0–5%). Response variables included disintegration time, amount of drug released at 15 and 60 min, and tablet hardness, all analyzed according to USP 31.Results and discussion: Increasing HPC-SL together with CrosPVP not only increased tablet hardness but also reduced disintegration time. Optimal condition was achieved in the range of 5–9% HPC and 3–5% CrosPVP, where tablet properties were at least 70 N tablet hardness, less than 1 min disintegration, and within the USP requirements for drug release. Testing the optimized formulation with four different commercial CBZ samples, their variability was still observed. Nonetheless, all formulations conformed to the USP specifications.Conclusions: With the excipients CrosPVP and HPC-SL an immediate release tablet formulation was successfully formulated for high-dose CBZ of various commercial sources.

Study on Cutting Hard Thermal Spray Coating

The CBN and YG610 were used for remanufacture thermal spray coating cutting. The feed rates, in the experiment, adopt mode of creep feed. The experiment results showed that the YG610 can cut the thermal spray coating efficiently. And the surface finish qualities are all under Ra1, which can come up to the standard of common grinding. But the CBN tools will be broken in the cutting process, though it can perform well in the evenly qualitative material. By experimental investigation and analyses, it can be conclude that both the high hardness and huge impact exist in cutting process, which are main reasons which induce tools broken. So the materials of tools for cutting thermal spray coating need possess both sufficient hardness and toughness.

ATLAS Tracker Upgrade: Silicon Strip Detectors for the sLHC

After the successful start of the Large Hadron Collider (LHC) in November 2009 plans for a luminosity upgrade, called super-LHC (sLHC), are already advancing well. With a planned luminosity of 5 × 10 34 cm − 2 s − 1 the ATLAS detector has to cope with both a high instantaneous and integrated luminosity, providing a challenging environment for the tracking and vertexing detectors. Hence a new tracker is foreseen for the sLHC operation. As the radiation dose will increase according to the integrated luminosity, novel radiation hard detectors are required. A large R&D program is underway to develop silicon sensors with sufficient radiation hardness. In this article measurements of silicon strip sensors designed by the ATLAS Silicon Strip Sensor Upgrade Collaboration are presented. Both measurements of sensors irradiated to the expected sLHC fluences for different detector regions as well as comparisons between measurements of full size sensor properties and their technical specifications are shown. Furthermore the design challenges of the inner detector layout and support structures are presented.

Effect of Combined Shot Treatment and Nitriding on Galling Property of Die Used for High Strength Steels

The methodologies of controlling the surface texture of die by hybrid (double)-shot treatment and nitiding at a low temperature were examined for the development of long life cycle die applied to the high strength steel sheets. Hybrid-shot improved the galling property because of its lubricating effect, while nitriding at low temperature which is useful for decreasing distortion by heat-treatment had sufficient hardness of 1500 HV for anti-abrasion. Surface texture of die material, evaluated by using Fast Fourier Transformation (FFT) analysis revealed that the ratio of the spectrum amplitude between high and low frequencies was corresponding to the galling generation load.

Fundamental Properties and Nano-imprintabilities of Zr-, Pd- and Cu-based Glassy Alloy Thin Films

ABSTRACTWith the aim of investigating fundamental properties and nano-imprintabilities of glassy alloy in the film form, Zr49Al11Ni8Cu32, Pd39Cu29Ni13P19 and Cu38Zr47Al9Ag6 alloy thin films were fabricated on Si substrate by a magnetron sputtering method. These thin films exhibit distinct glass-tradition phenomenon and large supercooled liquid region of about 80 K, confirming as a glassy structure and have very smooth surface and sufficient hardness to maintain imprinted shape, which are suitable for nano-imprint processing. Moreover, thermal nano-imprintabilies of these obtained films are demonstrated by using a dot array mold with a dot diameter of 90 nm and a pitch of 180 nm. Surface observations revealed that periodic nano-hole arrays were successfully imprinted on the surface of these films and precisely corresponded to the periodic dot pattern of the mold. Particularly, Pd-based glassy alloy thin film indicated more precise pattern imprintability, namely, more flat residual surface plane and sharper hole edge. These results suggest that these glassy alloy thin films, especially Pd-based glassy alloy thin film have high potential for application to the nano-imprinting materials.

Electron-beam irradiation of polymer bracket materials

Electron-beam irradiation can be used to influence the properties of polymers. Electron beams cause cross-linking that enhances the molecular mass of the polymer; this leads to branched chains until, ultimately, a 3-dimensional network is formed. The aim of this study was to evaluate the effect of electron-beam irradiation on polymer bracket materials. Since polymers are commonly used materials for brackets, polyoxymethylene, polycarbonate, and polyurethane were chosen for this study. The acceleration voltage of the electron-beam device was 10 MeV, and the energy dose was 100 kGy with an electron accelerator (BGS beta gamma service, Rhodotron, Bruchsal, Germany). Three-medium wear, fracture toughness, and Vickers hardness tests were performed. The irradiated samples were compared with untreated control groups. Polycarbonate and polyurethane bracket materials have enhanced fracture toughness and Vickers hardness after electron-beam irradiation of 100 kGy and 10 MeV. Polyoxymethylene bracket materials showed significantly lower fracture toughness values after irradiation compared with the untreated control group. Polyoxymethylene had the best mechanical properties, followed by polycarbonate and polyurethane. Almost the same effects could be measured during the 3-medium wear test. Electron-beam postcuring improved Vickers hardness and fracture toughness of polymers with lower mechanical properties (polycarbonate and polyurethane). Polyoxymethylene, with sufficient hardness and fracture toughness, could not be improved with electron-beam postcuring.

Effect of two different superdisintegrants on combinaion dispersible tablets of isoniazid and rifampicin for oral treatment of tuberculosis.

Oral route of administration have wide acceptance up to 50-60% to total drug forms. Fast disintegrating drug delivery system has number of advantage such as faster onset of action, attractive elegance, ease of administration. In this study, an attempt has been made to study direct compression method, for formulation of fast disintegrating tablets of Isoniazid and Rifampicin, an anti-tubercular drug in view of enhancing bioavailability. These formulations have sufficient hardness and can be manufactured by commonly used equipment. Prior to formulation the pre-compression parameters were characterized for flow properties and prepared formulations were evaluated for physico-chemical parameters, X-ray powder crystallography, SEM and in-vivo bioavailability. All four formulations possessed good disintegration properties with total disintegration time of 25 to 40 seconds. The effects of different superdisintegrants and process variables on drug release profile and disintegration property were evaluated and results revealed the better drug release with different superdisintegrants such as Ac-di sol and Polyplastadone XL. All formulations are rapidly disintegrated in oral cavity as well as all formulations possess good anti-tubercular properties. SEM Showed the mechanical strength of the formulations affected the morphological changes after compression. Hence, it is evident from this study that fast dispersible tablets could be a promising delivery system for Isoniazid, Rifampicin and their combination with good mouth feel and improved drug availability with better patient compliance. Keywords: Isoniazid; Rifampicin; Superdisintegrants; Direct compression method; Bioavailability.

Microstructure and wear properties of novel sintered cold work steel and related particle reinforced composite materials

In the field of wear resistant materials it is known, that for certain applications steel based composites produced by powder metallurgy are beneficial due to a higher wear resistance compared to conventional cast materials. Early developments of these high wear resistant MMC were dependent on hot isostatic pressing but latest experimental findings nowadays also allow for a production by liquid phase sintering. Several materials systems have already been investigated which, however, lack of a sufficient hardness in the as sintered state. Especially for wear resistant coatings it would be beneficial to avoid a separate hardening of a coated component. The low hardness in the as sintered state is related to the transformation kinetics of the metallic matrix of the coating materials, typically leading to a comparatively soft pearlitic microstructure, if the cooling rate is too low. The use of a nickel alloyed PM cold work steel as matrix material avoids this restriction, as the formation of pearlite and bainite is delayed significantly, improving the hardenability of the steel. Adding coarse hard particles of chromium carbide (Cr3C2), aluminium zirconium oxide (AlZrO) or titanium carbide (TiC) to the steel powder, composite materials with a high abrasive wear resistance can be obtained by liquid phase sintering. The development of these materials, supported by thermodynamic calculations, is presented here together with results of the microstructural investigation and wear tests.

Preparation and Evaluation of Taste Masked Orally Disintegrating Tablets with Granules Made by the Wet Granulation Method

Using furosemide (FU) as a model drug, we examined the wet granulation method as a way to improve the taste masking and physical characteristics of orally disintegrating tablets (ODTs). In the wet granulation method, yogurt powder (YO) was used as a corrective and maltitol (MA) was used as a binding agent. The taste masked FU tablets were prepared using the direct compression method. Microcrystalline cellulose (Avicel® PH-302) and mannitol were added as excipients at a mixing ratio of 1/1 by weight. Based on the results of sensory test on taste, the prepared granules markedly improved the taste of FU, and a sufficient masking effect was obtained at the YO/FU ratio of 1 or more. Furthermore, it was found that the masking effect achieved by YO granules made with the wet granulation method was similar to or better than that produced by the granules made with dry granulation method. All types of tablets displayed sufficient hardness (over 3.5×10(-2) kN), and rapidly disintegrating tablets were obtained with YO granules produced at a mixing ratio of FU/YO=1/1, which disintegrated within 20 s. Disintegration time lengthened as the mixing ratio of YO to FU increased. In the mixing ratio of FU/YO=1/1, the hardness of tablets with granules made by the wet granulation method exceeded that of tablets with granules made by the dry granulation method, with minimal differences in disintegration time. The hardness and disintegration time of the tablets with granules made by the wet granulation method could be controlled by varying the compression force. In conclusion, YO was found to be a useful additive for masking unpleasant tastes. FU ODTs with improved taste, rapid disintegration and greater hardness could be prepared with YO-containing granules made by the wet granulation method using MA as a binding agent.

Response Surface Methodology to Optimize Novel Fast Disintegrating Tablets Using β Cyclodextrin as Diluent

The objective of this work was to apply response surface approach to investigate main and interaction effects of formulation parameters in optimizing novel fast disintegrating tablet formulation using β cyclodextrin as a diluent. The variables studied were diluent (β cyclodextrin, X (1)), superdisintegrant (Croscarmellose sodium, X (2)), and direct compression aid (Spray dried lactose, X (3)). Tablets were prepared by direct compression method on B2 rotary tablet press using flat plain-face punches and characterized for weight variation, thickness, disintegration time (Y (1)), and hardness (Y (2)). Disintegration time was strongly affected by quadratic terms of β cyclodextrin, croscarmellose sodium, and spray-dried lactose. The positive value of regression coefficient for β cyclodextrin suggested that hardness increased with increased amount of β cyclodextrin. In general, disintegration of tablets has been reported to slow down with increase in hardness. However in the present study, higher concentration of β cyclodextrin was found to improve tablet hardness without increasing the disintegration time. Thus, β cyclodextrin is proposed as a suitable diluent to achieve fast disintegrating tablets with sufficient hardness. Good correlation between the predicted values and experimental data of the optimized formulation validated prognostic ability of response surface methodology in optimizing fast disintegrating tablets using β cyclodextrin as a diluent.

Correlation of Microstructure and Ballistic Performance of Multilayered Zr-based Amorphous Surface Composites Fabricated by High-Energy Electron-Beam Irradiation

In this study, multilayered, Zr-based amorphous surface composites were fabricated by high-energy electron-beam irradiation; the correlation of their microstructure, hardness, compressive properties, and fracture properties with ballistic performance was investigated. The mixture of Zr-based amorphous powders and LiF + MgF2 flux powders was deposited on a pure Ti substrate or a plain carbon steel substrate, and then an electron beam was irradiated on this powder mixture to fabricate a one-layered surface composite. The multilayered surface composite was fabricated by an irradiating electron beam several times again onto the powder mixture deposited on the one-layered surface composite. The microstructural analysis results indicated that a small amount of fine crystalline particles was distributed homogeneously in the surface composite layer. Because the surface composite layers absorbed the ballistic impact energy by forming many cracks or microcracks, the surface composite plates were not perforated during the ballistic impact test. On the one hand, in the surface composite without containing ductile β phases, the composite layer was cracked completely and fallen off from the substrate. On the other hand, a small amount of fragmentation was found in the impacted area of the composite containing β phases because it had the sufficient hardness and fracture toughness simultaneously for effectively blocking the traveling of a projectile, thereby improving ballistic performance.

Neutron diffraction study of Levantine Middle Bronze Age cast axes

A neutron diffraction study on 6 Middle Bronze Age axes, cast from tin bronze or from arsenical copper, has been carried out using the ENGIN-X beamline at ISIS. The gauge volumes dimensions were 4x4x10mm3; data were collected along the lengths of the objects in their central parts, as well as on the blades, in order to establish the spatial phase contents. Average phase fractions were determined by Rietveld analysis. The main phases identified were solid solutions, corrosion phases and metallic Pb inclusions. We have observed distributions of lattice constants of the solid solutions Cu-Sn, and Cu-As inside each gauge volume in the central parts of the axes due to segregation, or liquation effects. However, the Cu-Sn variations were significantly less pronounced in comparison with typical inhomogeneity effects in as cast objects. The results indicate that the studied Middle Bronze Age axes were probably treated at high temperatures for homogenization necessary for generating sufficient hardness, especially on the blades.

Improved preparation of recycled polymers in chemical recycling of fiber-reinforced plastics and molding of test product using recycled polymers

We examined an improved preparation method of recycled unsaturated polyester resin from recovered monomeric materials obtained from the depolymerization of fiber-reinforced plastics (FRPs). The formation of unsaturated polyester progressed smoothly in the presence of catalytic amounts of Ca(OAc)2 and Ti(OBu)4. The quality of the resin was estimated by the durometer hardness test. The strength test of FRP board prepared from recycled resin showed sufficient hardness for practical use (about 94% of the tensile strength of new resin). We examined the recycled resin by using it to mold successfully an actual test product.

Maltodextrin: A Novel Excipient Used in Sugar-Based Orally Disintegrating Tablets and Phase Transition Process

The recent challenge in orally disintegrating tablets (ODT) manufacturing encompasses the compromise between instantaneous disintegration, sufficient hardness, and standard processing equipment. The current investigation constitutes one attempt to fulfill this challenge. Maltodextrin, in the present work, was utilized as a novel excipient to prepare ODT of meclizine. Tablets were prepared by both direct compression and wet granulation techniques. The effect of maltodextrin concentrations on ODT characteristics--manifested as hardness and disintegration time--was studied. The effect of conditioning (40 degrees C and 75% relative humidity) as a post-compression treatment on ODT characteristics was also assessed. Furthermore, maltodextrin-pronounced hardening effect was investigated using differential scanning calorimetry (DSC) and X-ray analysis. Results revealed that in both techniques, rapid disintegration (30-40 s) would be achieved on the cost of tablet hardness (about 1 kg). Post-compression conditioning of tablets resulted in an increase in hardness (3 kg), while keeping rapid disintegration (30-40 s) according to guidance of the FDA for ODT. However, direct compression-conditioning technique exhibited drawbacks of long conditioning time and appearance of the so-called patch effect. These problems were, yet, absent in wet granulation-conditioning technique. DSC and X-ray analysis suggested involvement of glass-elastic deformation in maltodextrin hardening effect. High-performance liquid chromatography analysis of meclizine ODT suggested no degradation of the drug by the applied conditions of temperature and humidity. Overall results proposed that maltodextrin is a promising saccharide for production of ODT with accepted hardness-disintegration time compromise, utilizing standard processing equipment and phenomena of phase transition.