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This study aims to the optimization using three factors and three-level parameters (sliding speed [rpm], sliding distance [m/s] and load [N]) of design matrix were adapted to Box–Behnken design using design expert v8.0 software. Based on the parameters, to develop the linear regression equation and to find the significant considerable wear process parameters based on output responses like wear loss (WL) and coefficient of friction (COF) value of polymer matrix composites (PMC) specimen of Acrylonitrile-butadiene-styrene (ABS)/cellulose composite (80 wt% of ABS and 20 wt% of cellulose).

The fabrication of the ABS/cellulose composite sample was carried out by the simple hands-on stir process method. As per the American Society for Testing and Materials G99 standard, the sample was made by the molding process. The wear analysis was made by multi tribotester TR25 machine and validated the developed model by using statistical software design expert v.8.0 and numerical tools like analysis of variance. The surface morphology [field emission scanning electron microscopy (FESEM) analysis] of the sample was also observed using the Quanta FEG-250 FESEM instrument.

The parameters like sliding speed, sliding distance and load are independently affected the COF value and WL of the 80% of ABS matrix and 20% cellulose reinforced composite material. The regression equations were generated by the coefficient of friction value and WL, which predicted the minimum WL of 80% of ABS matrix and 20% of cellulose reinforced composite material. The worn surface analysis result exposes the worn path and equal distribution of reinforcement and matrix on the surface of composite material.

The literature survey revealed a small number of studies available regarding wear analysis of ABS matrix and cellulose reinforced composite materials. In the present work, to fabricate and evaluate the wear performance of PMC (80% of ABS and 20% of cellulose) depends on the WL and COF value. The maximum and minimum COF value (µ) of 80% of ABS and 20% of cellulose composite material is 4.71 and 0.28 with the optimized wear process parameter by 1,000 mm of sliding distance, 0.25 (m/s) of sliding speed and 9 N of load.

This paper aims to investigate the resultant optimal ultimate tensile strength, elongation, flexural strength and modulus, compression strength and impact strength of fabricated alkali-treated Lagenaria siceraria fiber (LSF)-reinforced polymer matrix composite by optimizing input factors and microstructural characterization by influencing fiber length, fiber concentration and treatment condition of LSF.

The fabrication of LSF-reinforced composite specimens involved surface treatment followed by custom experimental design using a simple hand layup process. The wear analysis was performed by a multi-tribotester TR25 machine, and the developed model was validated by using statistical software Design Expert V.8 and analysis of variance (ANOVA). The surface morphology of the sample was also analyzed by field emission scanning electron microscopy.

The alkali treatment for LSFs had reduced the hemicellulose, and enhanced mechanical performance was observed for 30 wt.% concentration of L. siceraria in epoxy resin. Thermogravimetric analysis revealed thermal stability up to 245°C; microstructure revealed fiber entanglements in case of longer fiber length and compression strength reduction; and the surface-treated fiber composites exhibited reduced occurrences of defects and enhanced matrix–fiber bonding. Enhanced mechanical performances were observed, namely, ultimate tensile strength of 17.072 MPa, elongation of 1.847%, flexural strength of 50.4 MPa, flexural modulus of 3,376.31 GPa, compression strength of 52.154 MPa and impact strength of 0.53 joules.

The novel approach of optimizing and characterizing alkali surface-treated LSF-reinforced epoxy matrix composite was explored, varying fiber length and concentrations for specimens by empirical relations and experimental design to obtain optimal performance validated by ANOVA. Enhanced properties were obtained for: 7 mm fiber length and 30 wt.% concentration of fiber in the composite for alkali-treated fiber.

This study aims to evaluate the development of composites made of epoxy (E) resin with different weight percentages of polypropylene (PP) and graphene oxide (Go) to form nanocomposite plates.

A hand lay-up process was used to develop 21 different composites, with varying concentrations of PP (5%–35%) and Go (5%–35%). A ternary composite of E matrix was produced by combining binary fillers PP and Go (5%–35%) in a 1:1 ratio to a (95%–5%) solution. With the help of adopting the melt condensation deal to extract Go, the modified Hummers method was used to make Go platelets.

Through field emission scanning electron microscopy (FESEM) and X-ray diffraction investigations, the particulate’s size and structural characteristics were identified. Based on the FESEM analysis of the collapsed zones of the composites, a warp-and-weft-like structure is evident, which endorses the growth yield strength, flexural modulus and impact strength of the composites.

The developed nanocomposites have exceptional mechanical capabilities compared to plain E resin, with E resin exhibiting better tensile strength, modulus and flexural strength when combined with 10% PP and 10% Go. When compared to neat E resin, materials formed from composites have exceptional mechanical properties. When mixed with 10% PP and 10% Go, E resin in particular displays improved tensile strength (23 MPa), tensile modulus (4.15 GPa), flexural strength (75.6 MPa) and other attributes. Engineering implications include automobile side door panels, spacecraft applications, brake pads and flexible battery guards.

This study aims to determine the effect of different friction stir welding (FSW) parameters on mechanical and metallurgical characteristics of aviation-grade AA8090 alloy joints.

Response surface methodology with central composite design is used to design experiments. The mechanical and microstructure characteristics of the weld joints have been studied through a standardized method, and the influence of threaded pins on the joint microstructure has also been assessed.

From a desirability strategy, the optimum parameters setting of the friction stir welding was the tool rotational speed (TRS) of 800, 1,100 and 1,400 rpm; tool traverse speed (TTS) of 20, 30 and 40 mm/min; and tilt angle 1°, 2° and 3° with different tool pin profiles, i.e. cylindrical threaded (CT), square threaded and triangular threaded (TT), for achieving the maximum tensile strength, yield strength (YTS) and % elongation as an output parameter. The TRS speed was the highest weld joint characteristics influencing parameter. Peak tensile strength (378 MPa), percentage elongation (10.1) and YTS (308 MPa) were observed for the optimized parametric value of TRS-1,400, TTS-40 mm/min and TA (3°) along with CT pin profile. Microstructure study of the welded surface was achieved by using scanning electron microscope of output parameters. When the tool rotation speed, tool transverse speed, tilt angle and tool profile are set to moderately optimal levels, a mixed mode of ductile and brittle fracture has been seen during the microstructure analysis of the welded joint. This has been aided by the material’s plastic deformation and the small cracks surrounding the weld zone.

From the reported literature, it has been observed that limited work has been reported on aviation-grade AA8090 alloys. Further thermal behavior of welded joints has also been observed in this experimental work.

The purpose of this paper is to describe a method permitting the creation of a realistic model of spherical roller bearing with the aim of determining contact stress and fatigue life based on dynamic loading conditions. The paper also aims to recognize the effect of tolerance values on contact stress and fatigue life. Motion and load transmission in spherical roller bearing occurs within the assembly by elliptical curved contacting surfaces. The stress produced by the transmitted load would be very high because of least contacting area between these surfaces.

The paper describes a methodology to determine contact stress using analytically as well as finite element method for spherical roller bearing. The comparison for the both each approach for contact stress at different loading condition is carried out. Prediction of fatigue life based on dynamic loading conditions for bearing is also determined using finite element model. The effect on induced contact stress and fatigue life by varying tolerances on inner race dimensions have been found out.

The paper suggests that the maximum stress produces at the start or end of the contacting arc under static loading condition in spherical roller bearing. The analytical and finite element approach is in good agreement. The fatigue life prediction is useful for selecting loading conditions for various applications of double row spherical roller bearing. Tolerance level at inner ring raceway radius is kept high because of manufacturing constrain of complex curvature geometric shape.

The present approach does not consider dynamic loading conditions for contact stress analysis. Therefore, researchers are encouraged to analyze the effect of wear, lubrication and other tribological aspects on bearing life.

The paper includes determination of contact stress and prediction of fatigue life for spherical roller bearing using analytical as well as finite element approach. The tolerance values at inner race are identified as per manufacturing constraint based on contact stress and fatigue life.

Under-race lubrication can increase the amount of lubricating oil entering a bearing and greatly improve lubrication and cooling effects. The oil-air two-phase flow and heat transfer characteristics inside a ball bearing with under-race lubrication play a key role in lubrication and cooling performance. The purpose of this paper is to study these two characteristics, and then provide guidance for lubrication and heat dissipation of bearing with under-race lubrication.

In this paper, a simplified three-dimension heat transfer model of ball bearing with under-race lubrication is established; the coupled level set volume of fluid method is used to track the oil-air two-phase flow, and the Palmgren method is used to calculate the heat generation. The influence of rotation speed and inlet velocity on oil volume fraction, temperature and convection heat transfer is investigated. A temperature test for under-race lubrication is carried out.

Because of the centrifugal force, lubricating oil is located more on the outer ring raceway. As the rotation speed decreases and the inlet velocity increases, the oil volume fraction increases and the temperature decreases. Furthermore, the area with high oil volume fraction has a large convection heat transfer coefficient and low temperature. The error between the simulation temperature and the test temperature is within 10%.

The research on the temperature field and convection heat transfer characteristics of under-race lubrication ball bearings at different rotation speeds and inlet velocities is rarely involved.

The purpose of this paper was to present a simple and convenient technology to produce the electronic-grade CuO. The prepared electronic-grade CuO fully meets the demands of industrial production of high density interconnect (HDI).

A new method termed as open-circuit potential-time technology is proposed to measure the dissolution time of CuO in plating solution. X-ray diffraction (XRD) scanning electron microscopy (SEM) and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) were used to characterize the prepared CuO. Solder shock and reflow tests were carried out to examine the Cu deposits.

All aspects of the prepared CuO meet the demands of printed circuit board (PCB) industry.

A simple and convenient technology was presented to produce the electronic-grade CuO. A new method was proposed to determine the dissolution time of CuO in plating solution.

The study aims to test the color fastness of wool and linen fabrics dyed by simple immersion in ethanol dissolutions of fungal dyes.

Ethanol dissolutions of Talaromyces australis and Penicillium murcianum dyes were prepared to a concentration of 0.3% and used to dye wool and linen samples by immersion. Color fastness to washing, dry cleaning, wet and dry rubbing, perspiration and light, were tested according to AATCC standards.

Color fastness reached acceptable results at dry cleaning and wet and dry rubbing by crocking but did not performed well at laundering, perspiration and light exposure. Results indicate that ethanol dissolutions of tested dyes had better affinity for wool fabrics than linen, but the dyeing method requires further improvements to be considered attractive for full scale applications.

In this work sustainability of fabrics dyeing is improved by using natural pigments produced by filamentous fungi and a method to dye that requires no increment of temperature and mordants.

Genetics, a discipline of biology, is one of the most recent and rapidly advancing disciplines in science. This study aims to present a bibliometric analysis of the genetics research output of Iranian authors, map the intellectual structure of these studies and investigate the development path of this literature and the interrelationships among the main topics.

This study searched the Web of Science database for documentation of Iranian-published genetics research published up to 2020. Further, this study used HistCite software to profile and analyze the most cited articles and references and to draw their historiographies.

A database search revealed 21,329 documents that created the study population. The highest cited publications based on the Global Citation Score (GCS) and Local Citation Score (LCS) achieved scores of 602 and 47, respectively. The publication growth rate study demonstrated consistent expansion over time. The scientific maps based on LCS and GCS had five and four clusters, respectively. Furthermore, journal articles emerged as the predominant type of publication.

The significance of this study is in its contribution to understanding the genetics research position in Iran, informing policymakers and researchers, helping scientific collaboration and its impact on public attitudes and quality of life. The results of the present study, with benefits for various groups of communities, such as policymakers, academic groups and public society, can bridge the gap between theoretical research and practical implications.

The results of this study, by helping future advancement in health care, medical genetics and disease prevention, may have a direct and indirect positive influence on the quality of life. Furthermore, it may lead to more informed discussions on health care and biotechnology as well as influencing public attitudes and perceptions.

Ultimately, this study concludes that despite the proliferation of publications in terms of quantity and complexity, especially in areas such as disease diagnosis, prevention and treatment, there remains a need for more attention to other facets of genetics such as biology and biotechnology. Iranian publications are most related to population genetics, human genetics, molecular genetics, medical genetics, genomics, developmental genetics and evolutionary genetics out of 10 branches of genetics. This study reveals patterns in scientific outputs and authorship collaborations and plays an alternative and innovative role in revealing Iranian research trends in genetics.