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Currently, paper pulping production from woody materials has many disadvantages due to its high energy, chemical, water consumption, methane emissions, and deforestation. However, the use of non-woody materials solves these problems. This study focused on the use of non-virgin raw material (Enset leaf fiber) in pulp and paper making. Enset leaf residues are the primary solid residues after the steam plant is used for “Kocho” processing. This leaf fiber has a lignocellulose component, converting this residue into Pulp and paper is crucial in terms of economic and waste management via the Kraft process. It has a higher fiber quality, lower energy consumption, and high recoverability of the chemical raw materials used in the process. The chemical composition of the Enset leaf fiber was analyzed using the Technical Association of Pulp and Paper. It has an excellent fiber length (2.12±1.46mm), fiber diameter (26.55±15.6µm) and acceptable rigidity coefficient (1.05±0.07), and flexibility coefficient (125.23±0.04). The maximum pulp yield was obtained at a temperature of 120°C, NaOH concentration of 8%, and 40 min cooking time off, which was 69.92% w/w. The functional groups of the Enset leaf fiber and morphological characteristics of the fiber were investigated.

Natural fibers have been extensively studied as a reinforcement filler in obtaining composites, replacing partially synthetic fibers. The vast majority of these materials originate from agro-industrial waste with a high content of lignin and cellulose making it a very interesting material with low cost and good mechanical properties. The purpose of the study was to obtain a composite based on alkyl ketene dimer resin, for the manufacture of sustainable packaging, made of paper by adding a 10% (w/w) con-tent of green coconut fiber and sugarcane bagasse fiber, and evaluated the impact of the filler on the mechanical behavior of the systems. The studied material was characterized from mechanical tests, such as Ring Crush Test (RCT) and Concora Medium Test (CMT) evaluating the maximum resistance supported by centimeter in the pre-pared composites, by the specimens. Through the RCT tests, with 10% w/w fibers, it was possible to verify that the fiber from sugarcane bagasse reached an increase of about 1% in the reinforcement effect compared to pure paper, and a difference of up to 2% in strength mechanics in relation to coir fiber, and CMT tests shows the reinforcement effect of the presence of sugarcane bagasse fiber, with an increase of about 3% compared to pure paper, and with a mechanical strength higher by 1% compared to coconut fiber. Therefore, the study was funneled with sugar cane fiber, varying the content by 20 and 30 % (w/w), evaluating the impact on the dispersion of this filler in the polymeric matrix and, consequently, the mechanical response of the composite with these compositions. The conclusion of the study was that the system prepared with 20% (w/w) was the one that achieved the greatest optimization of the mechanical properties, evaluated by the tests. This type of material can be applied to obtain cardboard boxes with resistance to high loads, due to the achievement of good mechanical properties.

The characteristic pinched hysteresis behavior of memristors has been reported by stacks of a variety of materials. This paper aims to examine the principles of logic design using such two terminal memristive systems for high performance digital circuit applications. As against logic design with standard CMOS, the benefits of logic design with memristors have been stated. The realization and operation of memristor based AND and OR hybrid logic gates obtained by integrating memristors with standard CMOS logic have been discussed. The IMPLY and MAGIC logic families have been demonstrated by covering MAGIC NOR and NAND logic gate implementation with MAGIC NOR in detail. A qualitative comparison has been drawn towards the end of the paper to conclude on the suitability and application space for each of the logic families studied in this paper. This work also describes the hybrid CMOS-memristive logic family known as MRL (Memristor Ratioed Logic). With the addition of CMOS inverters, this logic family's OR and AND logic gates, which are based on memristive components, are given a full logic structure and signal restoration. The MRL family, in contrast to earlier memristor-based logic families, is compatible with conventional CMOS logic.

In this paper the effect of lattice friction stress on the process of dislocations annihilation is considered using dislocation dynamics method. It is shown that if dislocations of the opposite sign are located in the area where their own tension is greater than the friction stress, they annihilate. Consideration of this fact allows to connect the microscopic processes of annihilation with evolution of dislocation density in the sample under small external stresses and unloading. The area in which annihilation occurs is calculated to be proportional to the square of the friction stress/shear modulus ratio.It is also shown that the parameter responsible for the rate of dislocation annihilation depends on the cube of the ratio of the friction stress to the shear modulus, because it is inversely proportional to the number of annihilating dislocations and the time in which a dislocation pair annihilates.

The transporting of sediments across watershed systems and their placement in reservoirs causes expensive issues for the operators of dams in many different nations throughout the world. In addition to the reservoir's functional capacity steadily decreasing as sediment settles in it, silt removal is a sensitive and challenging process that frequently necessitates taking the reservoir out of service, which is practically unachievable in dry and semi-arid regions. De-silting by hydraulic dredging has recently become a necessity to increase their longevity. But during this operation there are load loss exists so it is necessary to find solutions to reduce it. The present paper revealed that use the Sodium Tripolyphosphate as a reducing agent of the friction factor during the hydraulic dredging of dams. To carry out this study, a rheumatic characterization of dams sediments and dams sediments -sodium tripolyphosphate mixtures was carried out using a torque controlled rheometer (Discovery Hybrid Rheometer DHR2 from TA instrument). The flow curves as a function of dose of sodium tripolyphosphate added to dam sediments were analysed by the modified Cross model. It is clearly shown, in this work, when the quantity of sodium tripolyphosphate is less than of 0.4 % causes a decrease in the yield stress, the zero shear rate viscosity (lower Newtonian plateau) and the infinite shear rate viscosity (upper Newtonian plateau). However, when dose of sodium tripolyphosphate is greater than the critical dose, the the yield stress, the zero shear rate viscosity (lower Newtonian plateau) and the infinite shear rate viscosity (upper Newtonian plateau) are increased. As a result, this study find that the increase on thixotropic behavior of dams sediments is occurred by the addition of sodium tripolyphosphate in a concentration ranging between 0.2 wt% and 0.8 wt% to 40 wt% and 45 wt% of dams sediments. The study also demonstrated that adding of 0.4 wt% of sodium tripolyphosphate to 40 wt% and 45 wt% dam sediments decreased the friction factor by 96% and 25% respectively.

This paper mainly studies the composition of strengthening phase, characteristic precipitation temperature and composition range of strengthening phase in Ti-Al-Mo-Zr-Si medical titanium alloy, and the influence of element changes on the content and microstructure of strengthening phase. Promote the formulation of thermodynamic process of titanium alloy powder metallurgy, as well as the formulation of alloy hot working and solid solution aging process. In this paper, Panda thermodynamic software is used to calculate the multicomponent alloy thermodynamics and multicomponent phase diagram of titanium alloy materials. The effects of Al, Mo, Zr, Si and other elements on the precipitation of strengthening phase and the phase transformation content of solidification structure were obtained. It is found that the content of Mo is more than 2 wt.% β phase transition precipitation angle. Meanwhile, in order to avoid the excess of precipitates such as Mo5Si3 and M3Si, the content of Mo should be less than 4.6 wt.%. The content of Zr can be maintained at about 1.5 wt.%. If the aging precipitation of the material is considered, it can be controlled to be less than 2 wt.%. The content of this paper is the basis and improvement of titanium powder metallurgy technology and rapid prototyping technology.

Sustainable development requires green energy and low carbon footprint in manufacturing sector of photovoltaic systems. The electrical connections of photovoltaic cells need to have low electrical resistance in order to reduce the electrical losses and therefore to improve the performance of the photovoltaic panels. This paper aims to present researches related to bonding of wires that connect solar cells by using microwave technology. The microwave bonding has the main advantage that offers fast bonding but, in the same time, this technology does not offer stability of the thermal heating. Two different unwanted phenomena like thermal runaway and plasma arc discharge often lead to the damaging of copper and aluminum wires used in electrical connection. The study presented in this paper is focused on simulation of the thermal field developed in copper wires in order to optimize the bonding process and increase the quality of products. The simulation of the thermal field has been done using Fourier equations for conducting heating in copper materials and eutectic alloys. The simulation model has been validated through experimental heating using a 6 kW water-cooled microwave generator controlled by a matching load auto-tuner for best transfer of the power from generator to copper wires. The temperature has been measured in real time using an infrared pyrometer for metals with 2.3 μm spectral range and measurement range between 0o C and 7000 C. The study is finalized with elaboration of mathematical model for microwave-injected power as function for temperature developed in copper wires that can be applied with success in further microwave bonding applications of copper wires. In addition, the electrical resistance of bonded wires was measured in order to collect feedback for improving the microwave bonding process.

In this paper, a hollow square cross-section carbon fiber/epoxy composite beam was designed and manufactured. Evaluation of the beam behavior considered orientation and stacking sequence, aiming to reduce the number of layers and weight. Finite element method (FEM) was used to simulate the performance of the composite beam under 3-point bending and using three failure criteria, Tsai-Hill, Tsai-Wu and maximum stress. In order to identify the input parameters for the model, flat composites were tested under tension and compression. It was concluded that a minimum of 12 layers of unidirectional carbon fiber were required to reach the required load (44.5 kN). The prototype was successfully fabricated by vacuum-infusion process and subjected to 3-point bending test. The experimental failure load was within the predicted range by the Tsai-Hill failure criteria and maximum stress.

The recent developments in dielectric elastomers (DE) are spectacular. Currently, a DE as an actuator, 0.15 g of acrylic sandwiching SWCNT electrodes, is capable of lifting a weight of 8 kg by more than 1 mm at a speed of 88 msec. In the near future, DE motors could be used to drive electric vehicles. Moreover, the DE can be used as a high-efficiency sensor with the same structure. With a diameter of 20 mm and a thickness of 0.5 mm, it can accurately measure pressure from several kg to 150 kg. In addition, reversing this DE actuator (DEA) movement also enables high-efficiency power generation. In other words, when the DEA is stretched or pushed, it generates electric power. Single wall nanotubes (SWCNTs) were used as an electrode, and an acrylic DE power generation cartridge with a diameter of 80 mm was used. When the center of the DE power generation cartridge is pushed by about 15 mm, a power of 33.6 mJ is generated. Using these two DE cartridges, it was possible to charge a secondary battery through a DC converter. In addition to this power generator, practical research and development of power generation using wave power, wind power, waste heat, and fluids (ocean currents, water currents, etc.) is progressing. In this paper, we have described state-of-the-art DEAs, DE generators (including the case that the power generated locally by microgenerators are consumed locally), and DE sensors and explained their usefulness.

Spinel ferrite nanoparticles are potential candidates for multiple biomedical applications. Spinel ferrite nanoparticles have been studied extensively for understanding physical, chemical, electro-optical as well as magnetic properties which are fascinating due to cationic distributions corresponding to tetrahedral sites and octahedral sites in a cubic phase. Biocompatibility and large magnetic moment are basic requirements in spinel ferrite nanoparticles for efficient functioning in specific application purpose. Fe3O4 (magnetite) is an important member of spinel ferrite group with high chemical stability and ferrimagetic material property at nanodimension. Superparamagnetic state and biocompatibility of magnetite (Fe3O4) spinel ferrite nanoparticle has already been proven. Spinel ferrite magnetite nanoparticles have been developed based on precipitation of iron oxide using ferric and ferrous ions at the ratio 2:1 in alkaline media at and above 100°C. The experimental parameters have been set to synthesize pure and uniformly sized magnetite nanoparticles. No other phases of iron oxides were detected other than magnetite spinel phase in the XRD result. The average crystal size has been determined from XRD peak broadening. Absorption spectra were investigated using UV-Vis Spectrometer and FTIR. Thermal and magnetic measurements were carried out Digital Scanning Calorimeter and SQUID Magnetometer. One sample of the prepared nanoparticles with polymer coating of polyvinyl alcohol has been studied for superparamagnetic nature. Superparamagnetic particles show saturation value of magnetization 51.26 emu/g at 100 K. ZFC-FC curves for two samples with polymer coating of polyvinyl alcohol and hydroxy-propyl methyl cellulose have also been studied. Keywords: Spinel Ferrite, Magnetite, Ferrimagnetism, Transition metal oxide, Superparamagnetism. Statements and declarations Competing Interests: The authors declare that there is no competing financial interest that are related directly or indirectly to the reported work in this paper. Conflict of interest: There is no conflict of interest. Acknowledgements The Authors are grateful to IISER Bhopal, CRF facility for providing instrumentation facility to characterize magnetic properties. We acknowledge thanks to Lovely Professional University for providing us necessary characterization technique for the XRD analysis and thermal analysis.