Blow Torch Research Articles

Surface decoration of flexible Si3N4 nanowire membrane by hydroxyapatite micron-flake with excellent thermal insulation at 1300 °C

Flexible and excellent thermal insulation membranes are required as the thermal protection system materials of aerospace vehicles for next-generation space missions. Using ceramic membranes with ultralow thermal conductivity has been proved to be an effective way to protect the electronic components inside the fuselage. Herein, we decorate hydroxyapatite (HA) micron-flake onto Si3N4 nanowire membrane (SR), and investigate the thermal stability, fire-resistance and thermal insulating properties of the obtained SR decorated by HA micron-flake (SRHM). Surface decoration of HA micron-flake onto the SR results in the formation of well-interconnected junctions and the increase of interfacial thermal resistance. Due to the increased interfacial thermal resistance, the as-prepared SRHM exhibits good thermal insulation and outstanding fire-retardant performance. SRHM shows robust mechanical property with tensile strength value of 4.10 MPa, increased by 247.5% compared to the SR without the surface decoration by HA micron-flake. The thermal conductivity of SRHM is as low as 0.037 W m−1 K−1, reduced by 33.9% compared to the SR without the surface decoration by HA micron-flake. After SRHM is heated by a butane blow torch at 1300 °C for 30 min, no obvious change is observed in the macroscopic morphology. And the temperature of the backside for SRHM maintains at a stable temperature of ∼260 °C for 300 s, which is 1040 °C lower than that of the front side. Additionally, SRHM can protect the electronic components form being burnt under the heating of an alcohol lamp for 30 min. The successful preparation of such thermal insulating and fire-retardant SRHM will open up a new world for the widespread applications of ceramic membranes in the fields of aerospace vehicles.

Penggunaan Bubuk Bentonite untuk Menjernihkan Solar dari Olahan Sampah Plastik dan Oli Bekas

<p><strong>Plastic to Solar (PLATOS) machine is a machine that processes plastic waste or used oil into fuel through a pyrolysis process. Based on observations made, pure diesel produced by the PLATOS machine has a very cloudy color or brownish black. Therefore, to get clearer </strong><strong>fluid</strong><strong>, a purification process is needed, one of which is by using bentonite powder. Bentonite powder used is Bleaching Earth Bentonite which can bind or absorb dirt and unwanted materials in oil or diesel, so that oil or diesel becomes paler and clearer. The heating method is used in the purification trial using a blow torch fire flame gun and an aluminum pan as a diesel fuel container. This study aims to observe the extent of the effect of using bentonite to improve the quality of diesel fuel that has been produced. The research was conducted by conducting 4 times the purification process with the same amount of bentonite and diesel weight of 20 grams and 1 liter. Based on the experiments that have been carried out, it can be concluded that the diesel produced has specifications that are within the limits of diesel specifications set by the Director General of Oil and Gas. Overall, the results of these specifications can state that the use of bentonite powder with heating methods up to 100o C can improve the quality of diesel fuel well.</strong></p><p><strong><em>Keywords </em></strong><em>– Bentonite, Purification Process, Pyrolysis, Solar</em><em>.</em></p>

Erratum: Eyestalk Ablation to Increase Ovarian Maturation in Mud Crabs.

Erratum: Eyestalk Ablation to Increase Ovarian Maturation in Mud Crabs.

A Facile Method for Fabricating a Monolithic Mullite Fiber-Reinforced Alumina Aerogel with Excellent Mechanical and Thermal Properties.

Alumina aerogels are considered to have good application prospects in the high-temperature field. In this study, monolithic mullite fiber-reinforced alumina aerogels with excellent mechanical and thermal properties were synthesized via a facile method without the use of any chelating agents. This method successfully avoids the introduction of impurities during the use of catalysts and chelating agents while greatly reducing gelation time, and thus helps mullite fibers to uniformly disperse in the sol. The compressive stress at 80% strain of the obtained mullite fiber-reinforced alumina aerogels was as high as 16.04 MPa—426% higher than that of the alumina aerogel without the addition of mullite fibers. Regarding thermal properties, the shrinkage of the mullite fiber-reinforced alumina aerogels (AM) samples was less than 1% after heat treatment at 1300 °C for 2 h. Furthermore, the rear-surface temperature of the AM samples burned by a butane blow torch was only 68 °C. These outstanding properties make AM samples promising for application in thermal insulation materials in high-temperature fields such as aerospace and industrial thermal protection in the future.

Separation of hydrocarbon mixture of neopentane and n-hexane using NaY zeolite: Large distinct diffusivity.

A recently proposed method based on Levitation and Blow torch effects, is employed here to see if it can separate a mixture of neopentane and n-hexane. The results show that the mixture can be separated with a hot zone temperature of just 40 K above the ambient temperature, 300 K. The two components are found to accumulate at the two extreme ends of the zeolite column. The computed separation factor is in the range of 1015 -1020 (as compared to 104 for existing separation methods). The energy expense for the separation is significantly smaller than for existing separation methods by several orders of magnitude. Transport (D11 ), self (Ds ), and distinct diffusivities (Dd ) of the mixture were computed. The contribution of distinct diffusivity to the transport diffusivity is 70% as compared to 10%-30% seen in other separation methods and is larger by 2.3 times as compared to the self-diffusivity.

MODELLING AND ANALYSIS OF MECHANICAL PULLER

In this work, a simple, inexpensive, lightweight, low energy consumption mechanical extractor was developed to operate. The puller screw shaft was first designed and followed by the nut and then its collar top. Non-conventional shapes were assumed for the collars and handles. Finite element analysis was used to evaluate the stress in the arm and collar which had complex shapes. Finite element analysis reveals that pullers are less likely to fail under design working conditions. A designed 3 arm mechanical bearing puller was fabricated and used to remove many bearings stuck in the shaft. Attempting to remove a component mounted on a shaft without using the correct type of puller can be frustrating and time consuming. A snug fit, dirt, or corrosion can make the removal process difficult. Trying puller alternatives such as cutting, blow torch, and hammer poses obvious safety risks. There is also a risk of damaging the components of the machine you are trying to repair. Mechanical pullers are a great tool for removing components from different industries. Small types of pullers are widely used by technicians such as small car stores. Larger and higher tonnage models are used in heavy industry. This project, which requires the use of a puller, generally involves the maintenance of rotating equipment. Common components to remove include bearings, gears, wheels, pins, bushings, sleeves, couplers, sprockets and pulleys. Keywords: - Mechanical puller, collar, shaft, linkage arm, Design and analysis.

Kinetic Separation of n‐Hexane from 2,2‐Dimethyl Butane in Zeolite Y Using the Novel Levi–Blow Method

AbstractWith stricter emission standards being implemented the world over, the increase in the research octane number (RON) is essential for continued use of fuel. This can only be achieved through the separation of the linear alkanes from the branched alkanes or through conversion of linear to branched isomer. A separation method based on levitation and blow torch effects has been recently shown to separate neopentane from n‐pentane. The same method has been employed here to separate n‐hexane from 2,2‐dimethyl butane. This method provides a single step process in which the n‐hexane can be removed completely. The method yields very high purity with minimum expenditure of energy. Several properties have been computed to quantify the separation and indicate the degree of separation. The method if implemented experimentally, will provide a generic method for the separation of molecular mixtures. The steps necessary to realize the method experimentally are discussed. The setup for scaling up of the separation using the levi–blow method for industries is also presented.

Highly Stretchable, Crack-Insensitive and Compressible Ceramic Aerogel.

Ceramic aerogels are attractive candidates for high-temperature thermal insulation, catalysis support, and ultrafiltration materials, but their practical applications are usually limited by brittleness. Recently, reversible compressibility has been realized in flexible nanostructures-based ceramic aerogels. However, these modified aerogels still show fast and brittle fracture under tension. Herein, we demonstrate achieving reversible stretch and crack insensitivity in a highly compressible ceramic aerogel through engineering its microstructure by using curly SiC-SiOx bicrystal nanowire as the building blocks. The aerogel exhibits large-strain reversible stretch (20%) and good resistance to high-speed tensile fatigue test. Even for a prenotched sample, a reversible stretch at 10% strain is achieved, indicating good crack resistance. The aerogel also displays reversible compressibility up to 80% strain, ultralow thermal conductivity of 28.4 mW m-1 K-1, and excellent thermal stability even at temperatures as high as 1200 °C in butane blow torch or as low as -196 °C in liquid nitrogen. Our findings show that the attractive tensile properties arise from the deformation, interaction, and reorientation of the curly nanowires which could reduce stress concentration and suppress crack initiation and growth during tension. This study not only expands the applicability of ceramic aerogels to conditions involving complex dynamic stress under extreme temperature conditions but also benefits the design of other highly stretchable and crack-resistant porous ceramic materials for various applications.

FIRE TRAID: KEEPING THE LEGS APART

Fires in the Operating Room are more of a danger today as it was in past where cyclopropane or ether was usedbecause we now routinely use electrosurgical cautery in presence of fuel rich sources and oxidizers (air, oxygen and nitrous oxide). Now, with laser surgeries reaching more rapidly to our intuitionsthis risk is getting even larger. The effect of endotracheal tube being ignited while being ventilated by Oxygen and Nitrous oxide which essentially emit a blow torch is catastrophic. Although laparoscopic surgeries are done with carbon dioxide insufation which doesn’t support combustion, nitrous oxide diffuses intraabdominally and it gets easily mixed with bowel gases (methane and hydrogen) which can be ignited by cautery. These are a few examples of numerous sources of res in our OR.

Separating a linear C5 hydrocarbon from a branched C6 hydrocarbon: n-pentane from 2,2-dimethyl butane using levitation and blow torch effects.

The separation of linear from branched hydrocarbons is often required in many situations. There are several methods through which they can be separated but none provides a very high degree of purity or works without considerable expenditure of energy. Recently, a novel method was proposed to separate a mixture of neopentane and n-pentane. The present work demonstrates that the method can be used for separating other mixtures of hydrocarbons as well, by attempting the separation of a mixture of 2,2-dimethyl butane and n-pentane. Intermolecular interaction potentials have been modified to reproduce the experimental heat of adsorption and diffusivity of 2,2-dimethyl butane and n-pentane in zeolite NaY. The method involves choosing the correct host zeolite or other porous solids and introducing hot zones at appropriate positions. This result drives both the components to the opposite ends of the zeolite column, thus leading to separation. The achieved separation factors are much higher than what can be obtained with the help of existing methods. Different properties have been computed to understand the process involved in the separation of the mixture. The approach employed here uses very little energy for separation, making it suitable for green chemistry.

Separating Hydrocarbon Mixtures by Driving the Components in Opposite Directions: High Degree of Separation Factor and Energy Efficiency.

A radically different approach for separation of molecular mixtures is proposed. A judicious combination of levitation effect observed in zeolites with a counter intuitive Landauer blow torch effect provides driving forces for the two components of the mixture to move in opposite directions. Using nonequilibrium MonteCarlo simulations, we illustrate the efficacy of the method for separating real mixtures of both linear n-pentane and its branched isomer, neopentane, and linear n-hexane and its branched isomer, 2,2-dimethylbutane. The method yields several orders of magnitude improvement in separation factor and relative energy efficiency by using submicron zeolite column. The extremely high purity of the resulting single components makes the method best suited for green chemistry.

Resilient Si3N4 Nanobelt Aerogel as Fire-Resistant and Electromagnetic Wave-Transparent Thermal Insulator.

With the prevailing energy challenges and the rapid development of aerospace engineering, high-performance thermal insulators with various functions are attracting more and more attention. Ceramic aerogels are promising candidates for thermal insulators to be applied in harsh environments because of their low thermal conductivity and simultaneously excellent thermal and chemical stabilities. In general, the effective properties of this class of materials depend on both their microstructures and the intrinsic properties of their building blocks. Herein, to enrich the family and broaden the application fields of this class of materials, we prepared ultralight α-Si3N4 nanobelt aerogels (NBAs) with tunable densities ranging from 1.8 to 9.6 mg cm-3. The α-Si3N4 NBA realized resilient compressibility (with a recoverable strain of 40-80%), fire resistance (1200 °C butane blow torch), thermal insulation (0.029 W m-1 K-1), and electronic wave transparency (a dielectric constant of 1-1.04 and a dielectric loss of 0.001-0.004) in one material, which makes it a promising candidate for mechanical energy dissipative, fire-resistant, and electronic wave-transparent thermal insulator to be applied in extreme conditions. The successful preparation of such resilient and multifunctional α-Si3N4 NBAs will open up a new world for the development and widespread applications of ceramic aerogels.

As Fires Raged, Preparation, Teamwork Kept Disaster at Bay

As Fires Raged, Preparation, Teamwork Kept Disaster at Bay

Effect of different colours of light on performance of caged broilers

The objective of this study was to evaluate the performance of the broiler chicken (body weight, feed intake and feed conversion ratio) at the fifth week of age. The broiler chicks were weighed, leg banded and distributed randomly into four groups as treatments, battery type iron cages, feeders, waters and other equipments were thoroughly cleaned disinfected, dried, sterilized by blow torch and finally fumigated by use of mixture of KMnO 4 (potassium permanganates) and formaldehyde before use. The chicks were fed ad libitum with standard starter ration containing CP: 22 per cent and ME:2900 k.cal./kg feed upto 3 weeks age and then after broiler finisher ration with CP: 19 per cent and ME: 3000 k.cal./ kg feed upto 5 weeks age. The broiler chicks of all groups were kept under similar management practices except lighting regimes as per treatment upto five (5) weeks age in battery type iron cages in laboratory. It is concluded colours of light did not show any significant effect on feed intake and feed conversion ratio (FCR) in broilers. The colour of light has a significant effect on the weight gain at the fifth week of age. The milky white and yellow colours of light are effective to obtain higher weekly body weight at five weeks age of caged broilers.

Mercury-Free Gold Production Using Borax in Artisanal Small-Scale Gold Mining in Zimbabwe to Protect Health and Environment

Background: Low-budget mercury-free methods in artisanal small-scale gold mining are urgently needed to protect the environment and local and global health. The borax- method, which has been demonstrated in some countries, was tested in a gold mining area in Zimbabwe in December 2013. Methods: A one-day theoretical and two-day practical workshop was held in Kadoma to test the local feasibility to produce gold using a carpet in a sluice-box, extensive panning, and borax heated by a blow torch. (1) The acceptance of the new method by the miners was tested by collecting indices through discussions and observations, while (2) the availability of equipment and materials and (3) the suitability of the ore were tested due to trial and error. Results: A total of 50 invited stakeholders (miners, millers, government officials) listened carefully to the theoretical workshop, asked questions, and reported individual experiences. More than 30 of them participated in the practical workshop afterwards, further confirming their interest (1). The access to carpets and blow torches was very limited; other equipment was more available but also improvable (2). 1.11 grams of gold gained from ½ ton of ore was produced, while high potential for optimization was identified. The local miners noticed that more fine grained gold particles were captured than by amalgamation (3). Conclusions: The demonstration was hugely successful and the miners were impressed by producing mercury-free gold. An introduction of the borax-method on a global scale appears strongly justified, while testing and optimization at local levels and political support are needed. Epidemiological surveillance of mercury-related health effects is needed to prove the decreasing exposure. Acknowledgment: Thank you, Evan Ruzvidzo, Oliver Phiri, Stefan Muschack, and all project participants. Funding by the German Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety is gratefully acknowledged.

3-Dimensional Blow Torch-Molding of Fused Silica Microstructures

This paper presents a new and simple microfabrication process for creating various 3-D microstructures with high-aspect ratios . The key feature of this process is the use of a blow torch, which provides very intense localized heat for a short amount of time . The flame temperature can be up to 2500 °C for a propane-oxygen torch, above the melting temperatures of many high- Q materials. We demonstrate the fabrication of hemispherical and half-toroid (birdbath) shells from 100- μm-thick fused silica substrates. The structures have an rms surface roughness of 5.3 Å, which is crucial for achieving both high mechanical and optical Q. We create microbirdbath resonators by batch-level releasing the birdbath shells. We verify the resonance mode shapes of the degenerate n=2 wineglass modes using laser vibrometry and measure the frequency and Q of these modes using laser vibrometry and a capacitive measurement method. We demonstrate one of the best mechanical Q and smallest frequency split between the n=2 wineglass modes among existing micromechanical resonators. The birdbath resonator is promising for emerging applications such as the microrate-integrating gyroscope.

Characterization of two Ni–Cr dental alloys and the influence of casting mode on mechanical properties

PurposeThe aim of this study was to evaluate the tensile strength, elongation, microhardness (MHV), composition and microstructure of two Ni–Cr based alloy, cast under different casting conditions. MethodsBefore casting, the alloy ingots were evaluated as regards composition (EDX) and microstructure (Optical microscopy, SEM and EDX). The casting conditions were as follows: electromagnetic induction in an environment controlled with argon (EWA), electromagnetic induction in an environment under vacuum (EWV), electromagnetic induction without atmosphere control (EWNC) and blowtorch (BT). For each condition, 16 specimens were obtained, each measuring 25mm high and 2.5mm in diameter. The ultimate tensile strength (UTS) and elongation (EL) tests were performed in a Kratos machine (1.0mm/min). Fractured specimens were embedded in bakelite resin and polished for Vickers Microhardness analysis (1000g/10s) with 4 penetrations in each specimen. The UTS, EL and MHV results were evaluated for two-way ANOVA and Tukey's test (α=0.05). ResultsThe cross-product interaction was statistically significant for all properties evaluated (p<0.0001), lower UTS, VHN and higth elongation means were observed for the Ni–Cr–Mo–Be alloy tested when cast under the induction/argon (p<0.05). Higher UTS means were found for Ni–Cr–Mo–Ti alloy tested when cast under the induction/vacuum, and induction/air and flame/air condition (p<0.05). The two alloys show a microstructure with a dendritic formation with the presence of eutectic presence. ConclusionThe Ni–Cr–Mo–Ti alloy showed higth UTS, MHV and lowest EL comparaded with the tradicional Ni–Cr–Mo–Be, that show lowest UTS, MHV and higter EL when cast on induction/argon.

Role of vortex structures in excitation of condensed system self-oscillatory burning

The effect of free convection and vortex structures arising near the “singing” flame of a gasoline blow torch on excitation of thermal self-oscillations in a resonator tube is studied experimentally. A technique for measuring the oscillation amplitude of the gas column is suggested. It is found that the excitation of acoustic oscillations decreases the height of the singing flame and the mass velocity of burning but raises the gasoline combustion efficiency. The variation of the temperature field of the singing flame over an oscillation cycle is studied by digital photometry. Hysteretic dependences of the acoustic oscillation amplitude on the thermal power of the gasoline diffusion flame are obtained. A mechanism explaining the influence of vortex structures on the self-oscillatory mode of burning in condensed systems is discussed.

Separation of Mixtures at Nano Length Scales: Blow Torch and Levitation Effect

A new conceptual basis for the separation of multicomponent molecular mixtures is proposed. A separation method where different components of the mixtures are driven in opposite directions is realized by a judicious combination of two effects, viz., levitation and blow torch effects. Monte Carlo simulations of two Lennard-Jones binary mixtures with different-sized components are shown to be separated well if at least one of the components lies in the anomalous regime and the others lie in the linear regime. A separation factor of 10(8) is obtained on nano length scales as compared to 10(3), obtainable through conventional methods of separation on macrolength scales.

Effect of Landauer’s blow torch on the equilibration rate in a bistable potential

The kinetic aspect of Landauer's blow-torch effect is investigated for a model double-well potential with localized heating. Using the supersymmetric approach, we derive an approximate analytical expression for the equilibration rate as a function of the strength, width, and the position of the hot zone, and the barrier height. We find that the presence of the hot zone enhances the equilibration rate, which is found to be an increasing function of the strength and width of the hot zone. Our calculations also reveal an intriguing result, namely, that placing the hot zone away from the top of the potential barrier enhances the rate more than when it is placed close to it. A physically plausible explanation for this is attempted. The above analytical results are borne out by detailed numerical solution of the associated Smoluchowski equation for the inhomogeneous medium.