Low-cost Bulk Research Articles

An optimized pipeline for high-throughput bulk RNA-Seq deconvolution illustrates the impact of obesity and weight loss on cell composition of human adipose tissue.

Cellular heterogeneity of human adipose tissue, is linked to the pathophysiology of obesity and may impact the response to energy restriction and changes in fat mass. Here, we provide an optimized pipeline to estimate cellular composition in human abdominal subcutaneous adipose tissue (ASAT) from publicly available bulk RNA-Seq using signature profiles from our previously published full-length single nuclei (sn)RNA-Seq of the same depot. Individuals with obesity had greater proportions of macrophages and lower proportions of adipocyte sub-populations and vascular cells compared with lean individuals. Two months of diet-induced weight loss (DIWL) increased the estimated proportions of macrophages; however, two years of DIWL reduced the estimated proportions of macrophages, thereby suggesting a bi-phasic nature of cellular remodeling of ASAT during weight loss. Our optimized high-throughput pipeline facilitates the assessment of composition changes of highly characterized cell types in large numbers of ASAT samples using low-cost bulk RNA-Seq. Our data reveal novel changes in cellular heterogeneity and its association with cardiometabolic health in humans with obesity and following weight loss.

Analysis of carbon and nitrogen from atmospheric sources by bulk deposition sampling at various locations in Germany

Atmospheric deposition of particulate matter is an important indicator of air pollution and a significant factor in material surface fouling. The elemental composition of this nutrient-containing dust depends largely on the exposure region and time as well as on climate. Therefore, in this paper we report an analysis of atmospheric pollutions with a self-made low-cost bulk deposition sampler directed at sampling deposition via air transport and rainfall. We used the device in diverse environments - thus comparing an urban region, an area surrounded by forest and an area mainly dominated by agriculture. The total organic carbon (TOC) and total nitrogen (TN) amounts were selected as indicator parameters and analyzed in a biweekly rhythm for three and a half and two years, respectively. The TOC value responded to particulate matter in the urban area, especially significant were the influences of the New Year's firework in urban and pollen in the rural forest area. In contrast, the TN value was more under the influence of the nitrogen emissions in the agriculture-dominated area. However, the TN value did not correlate with the NOx values in the urban area because the atmospheric nitrogen emissions in the city might originate from various emission sources. Summarizing, the TOC and TN values of the self-made low-cost bulk deposition sampler were in good agreement with environmental events of their immediate surrounding. Moreover, the selected containers and sampling procedures are universally applicable to monitor and analyze organic as well as inorganic parameters (e.g. metal ions) of atmospheric deposition.

Abstract 4300: Large-scale, low-cost, and accurate measurement of cancer evolutionary dynamics from clinical patient samples

Abstract Introduction: Cancer is a dynamic evolutionary process; thus, the evolutionary history of a cancer should strongly influence its future trajectory and so the clinical outcome of patients. However, accurately assessing an individual cancer’s evolutionary history in a scalable and clinically relevant manner is currently an open problem. To address this, we introduce a novel methodology (EVOFLUx) to quantitively infer the history of a cancer from single time-point bulk samples using inexpensive, standard methylation arrays. Description of Methodology: We recently identified fluctuating CpGs (fCpGs), which are CpGs that neutrally and stochastically change methylation state over time in individual cells, uniquely barcoding cells and thus enabling high temporal-resolution lineage tracing approaches. In a bulk population of cancer cells, the distribution of fCpG methylation is determined by the evolution of the population and thus encode a cancer’s past clonal dynamics. Here, we have developed a general computational approach to model how the patterns of fCpGs vary according to the evolutionary history of a growing cancer, and a Bayesian inference method to infer these parameters from data. Results We applied EVOFLUx to quantify the evolutionary dynamics of 1,976 lymphoid cancers, finding that the tumor growth rates, malignancy age and epimutation rates varied by orders of magnitude across disease types. In addition, EVOFLUx allowed us to test for the presence of ongoing subclonal selection and validated our inference with matched whole exome sequencing data. Alongside characterizing the evolutionary dynamics within single bulk samples, fCpGs also allow for the inference of the phylogenetic relationships between longitudinal samples, which we validated with whole genome sequencing. Within cancer types, more aggressive subtypes typically had elevated growth rates. In our clinically annotated cohort of chronic lymphocytic leukemia (CLL) samples, we found that patient-specific evolutionary dynamics are strongly associated with outcome. Conclusions: Hence, we present a powerful new method that uses widely available, low-cost bulk DNA methylation data to precisely measures cancer evolutionary dynamics in patient samples with clinical implications. Citation Format: Calum Gabbutt, Martí Duran-Ferrer, Heather Grant, Diego Mallo, Ferran Nadeu, Jacob Househam, Neus Villamor, Olga Krali, Jessica Nordlund, Thorsten Zenz, Elias Campo, Armando Lopez-Guillermo, Jude Fitzgibbon, Chris P. Barnes, Darryl Shibata, José I. Martin-Subero, Trevor A. Graham. Large-scale, low-cost, and accurate measurement of cancer evolutionary dynamics from clinical patient samples [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4300.

Mechanical Response of Zr51.9Cu23.3Ni10.5Al14.3 Metallic Glass Ribbon under Varying Strain Rates

In this work, we investigated the mechanical behavior of a low-cost Zr51.9Cu23.3Ni10.5Al14.3 (at. %) metallic glass ribbon prepared with industrial-grade material through the melt-spinning method. The ribbons have good appearances and almost no defects. The mechanical behavior associated with the corresponding microstructure of the ribbon was tested at different strain rates. Striation and veining patterns were observed in the crack propagation zone and the fast fracture zone. The results show that the tensile strength of the ribbons exceeds 1 GPa. Therefore, they are considered to have good potential for industrial applications. This study could contribute to the preparation of low-cost bulk metallic glass.

High-rate and -yield continuous fluidized-bed bioconversion of glucose-to-gluconic acid for enhanced metal leaching

Continuous low-cost bulk biolixiviant production remains as one of the main challenges of heterotrophic bioleaching towards large scale application. This study aimed at developing non-aseptic Gluconobacter oxydans-amended fluidized-bed reactor (FBR) process for continuous production of gluconic acid for efficient leaching of rare earth elements (REEs) and base metals from spent nickel-metal-hydride (NiMH) batteries. In preliminary experiments, the FBR became contaminated and massively overgrown by air-borne fungus, Leptobacillium leptobactrum. In a series of batch bioassays, operational conditions were investigated to discourage the fungal activity i.e., an ecologically engineered niche for gluconic acid production. High gluconate concentration (≥100 g/l) and/or low pH (≤2.5) gave a selective preference for G. oxydans growth over L. leptobactrum and controlled the activity of possible contaminants during FBR continuous operation. The highest gluconic acid production rate of 390 g/l∙d with corresponding glucose-to-gluconic acid conversion yield of 94% was obtained at hydraulic retention time (HRT) of 6.3 h and 380 g/l∙d glucose loading rate. Using the FBR effluents as leaching agents, respectively, total base metals and REEs leaching yields of up to 82% and 55% were achieved within 7 days at 1% (w/v) spent battery pulp density. The obtained glucose-to-gluconic acid conversion rates and yields were one of the highest reported for any glucose biotransformation process. The REE leaching yields were higher than those reported for similar high metal-grade REE secondary sources. The high-rate glucose-to-gluconic acid bioconversion in the non-aseptic system utilizing microbial ecology based FBR operation strategy rather than aseptic chemostats indicates industrial feasibility of gluconic acid production and thus, the applicability of heterotrophic bioleaching.

Analysis and Design of a Non-Magnetic Bulk CMOS Passive Circulator Using 25% Duty-Cycle Clock.

A circulator, which is a non-reciprocal device, is widely used in full-duplex systems, future communication and sensing networks, and quantum computing, and it is difficult to implement a passive topology on a chip. Based on switch-based spatio-temporal conductivity modulation, in this study, we design and implement a non-magnetic on-chip passive circulator operating at the Ku band in a 90-nm bulk CMOS technology using a 25% duty-cycle I/Q clock signal. With the virtue of the four-phase non-overlapping clock signal, the proposed circulator achieves a 3.9 dB transmitter (TX)-to-antenna (ANT) and a 4.0 dB ANT-to-receiver (RX) insertion loss with a 1-dB bandwidth of 2.7 GHz (21.4%). The TX-to-RX isolation is better than 17.2 dB, and the TX-to-ANT IIP3 and ANT-to-RX IIP3 are 19.7 dBm and 20.0 dBm, respectively, while occupying a die area of 1.55 mm × 1.15 mm. Although low-cost bulk CMOS technology is used, competitive isolation, linearity performance, and isolation bandwidth are achieved in the proposed design.

Unclonable Features via Electrospraying of Bulk Polymers

The ability to encode unclonable information using low-cost materials and processes is of significant interest for anti-counterfeiting and information security applications. In this study, we present a versatile approach based on electrospraying of polymer solutions to generate randomly positioned complex features as a form of physically unclonable function (PUF). The key advantage of this approach is that readily available low-cost bulk polymeric materials can form small and complex features using a simple process. Polymers of varying composition and molecular weight, together with different solvents and electrospraying conditions, are systematically explored to construct the parameter space for PUFs of varying characteristics. Besides the randomness in the spatial positions and sizes of features, the key advantage of the presented approach is the ability to generate complex 3D shapes, which are very difficult, if not impossible to fabricate with the most advanced fabrication techniques. The inclusion of photoluminescent molecules establishes an additional security layer. The additive nature of operation enables multiplexing, i.e., deposition of multiple materials on the same substrate. The fabricated PUFs have an average uniformity of 0.533 and uniqueness of 0.495, which are highly close to an ideal value of 0.5. The authentication is effectively performed using a feature detection algorithm without the need for markers and precisely defined rotation angles, greatly relaxing constraints associated with the imaging. Direct application of PUFs on the label of goods and authentication via a handheld microscope demonstrate the practical utility of the presented approach.

Exploiting Parasitic Capacitances in 3-D Inductors to Design RF CMOS Quasi-Elliptic-Type Broad-Band Bandpass Filters

A class of RF broad-band bandpass filter (BPF) with quasi-elliptic-type response in low-cost bulk CMOS technology is reported. It is based on the in-series cascade connection of lowpass and highpass filtering stages with 3-D inductors, whose parasitic capacitances are properly exploited. Specifically, they are used to transform the basic inductor into an LC tank, thus allowing to generate an upper transmission zero (TZ) that increases filtering selectivity and out-of-band power-rejection levels in a spurious-free/extended upper stopband. The layout of a basic third-order BPF cell shaped by four 3-D inductors and its lossless equivalent lumped-element circuit are detailed. By means of this lossless equivalent lumped-element model, its scalability to higher-order BPF designs by in-series cascading various BPF-cell replicas is also demonstrated. For experimental-validation purposes, an on-chip RF CMOS BPF prototype with 11-GHz center frequency and 68.5% 3-dB fractional bandwidth is developed using a 0.13- μm bulk CMOS technology. According to the measured results, it shows an upper stopband with minimum attenuation of 31.7 dB from 22.5 GHz to 67 GHz, alongside with TZs at 3.5 GHz and 22.5 GHz to produce sharp-rejection filtering.

Top-Down Ultrasonication-Assisted Exfoliation for Prebonded Phosphorene-Graphene Heterostructures Enabling Fast Lithiation/Delithiation.

We show a top-down synthesis approach to mass-produce phosphorene-graphene nanosheet composites with superior cycle stability and rate capability. Currently, using exfoliation to achieve two-dimensional (2D) materials is primarily limited to pure crystals. We discover that high-quality nanoscale 2D composite phosphorene-graphene sheets can be directly exfoliated from extremely low-cost bulk three-dimensional (3D) black phosphorus-graphite composites synthesized by mechanical milling while maintaining the chemical bonding and intimate electronic contact between 2D composite layers. The hybrid phosphorene-graphene material delivers high reversible capacities of 2030, 2003, and 1597 mAh/g at high current densities of 2, 4, and 6 A/g, respectively. Quantifying the dimensional electrochemical performance, we show that 2D phosphorene-graphene nanosheets not only have excellent electrochemical kinetics for fast lithium-ion diffusion and storage but also maintain the overall structural robustness of the entire electrode for long-term cyclability. This scalable synthesis paves the way for the practical application of phosphorene-graphene materials in batteries.

CMOS-Compatible Ex-Situ Incorporated Junctionless Enhancement-Mode Thin Polysilicon Film FET pH Sensor

In this article, a junctionless enhancement-type field-effect-transistor based pH sensor is proposed and fabricated through low-cost bulk CMOS aligned process. The thin device layer consists of uniformly ex-situ doped p-type polySi, yielding a junctionless doping profile throughout the active region. A thin Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> layer is deposited through atomic layer deposition as a sensing membrane, providing high site binding density for pH solutions. The effect of channel width (W <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">si</sub> ) ranging from 5 to 15 μm on threshold voltage and drain current sensitivities (ΔV <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sub> /ΔpH}, ΔI/ΔI <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</sub> ) respectively, have been investigated for different pH buffer solutions. For Ws of 5 μm, a maximum ΔV <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sub> /ΔpH sensitivity of 66.7mV/pH and current sensitivity of 98.9% was observed. Further, the drain current of ≃65$ nA at V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">gs</sub> = 0V and V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ds</sub> = -4V, yields low leakage operation of the proposed sensor. Furthermore, the repeatability of the proposed sensor is demonstrated by repeating the drain current measurements thrice with an interval of 10 minutes between corresponding measurements. A maximum shift of 30.9% among all measurements at pH = 6 which corresponds to 0.1 μA was observed, implying excellent repeatability of the proposed sensor.

Facilely transforming bulk materials to SnO/pristine graphene 2D-2D heterostructures for stable and fast lithium storage

Two-dimensional (2D) nano-structured tin monoxide (SnO) offers fascinating possibilities as anode material for lithium ion batteries (LIBs). 2D architectures of SnO are highly desirable to access advanced lithium storage properties however their application is impeded by the lack of synthetic method. In this study, we report a scalable synthetic route to facilely deriving SnO/pristine-graphene (p-G) 2D-2D heterostructure from bulk SnO and graphite. A “top-down” synthetic method was found effective in transforming SnO micro-sized particles into nanosheets down to a few nanometers in thickness. Assembled with pristine graphene (p-G), the SnO nanosheets were used to build a SnO/p-G heterostructure that delivers remarkable Li-ion storage performances: reversible capacities of 633.9 mAh g−1 after 100 cycles at 0.05 A g−1, and excellent cycling stabilities (0.027% capacity fade per cycle at 1 A g−1 after 700 cycles) were obtained. In comparison, raw SnO exhibited severe SEI over-growth and continuous capacity decay from the on-set at 0.05 A g−1. The structural advantages of 2D-2D heterostructure were elucidated to understand its exceptional lithium storage properties. This study demonstrates a facile and scalable strategy for producing 2D-2D heterostructures from low-cost bulk materials for LIBs application.

Passive Wireless UHF RFID Antenna Label for Sensing Dielectric Properties of Aqueous and Organic Liquids

The in situ wireless sensing of dielectric properties for organic aqueous solutions with a wide range of relative permittivities is presented. The use of an ultra-high frequency passive label antenna design attached to either clear borosilicate glass bottle or Petri plate is proposed, which allows for the unobtrusive, safe monitoring of the liquid solutions. The meandered dipole antenna (with a parasitic loop matching component) frequency is highly reliant on the chosen container as well as on the liquid present within, and adjusts with shifting dielectric properties. Tested solutions of high-relative permittivity (such as water) along with low permittivity, lossy liquids (such as xylene) presented distinctive frequency characteristics with read distances of up to 7 m for each type of container tested. The sensor was also able to detect `unknown' solutions and determine the dielectric properties by utilizing standard curve analysis with an accuracy of ±0.834 relative permittivity and ±0.050 S · m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> conductivity (compared to a standard dielectric measurement system available on the market). With the accuracy known, tuning the design to fit any necessary frequency is possible as a means to detect specific changes in any one liquid system. This sensor is a possible candidate for discreet real-time monitoring of liquid storage containers and an alternative for low-cost bulk liquid dielectric property identification, which could be implemented in areas requiring, constant, or remote monitoring as needed.

Computational fluid dynamics simulation study of the gas flow balance in a vertical HVPE reactor with a showerhead for low cost bulk GaN crystal growth

In order to make low cost bulk GaN single crystal with a high growth rate, we have built a vertical HVPE reactor with a showerhead configuration. The flow from the showerhead of the reactor is independently controlled by inner/outer two sets of gas supply lines. This special showerhead design makes the flow model different from the conventional showerhead reactors. We have employed a finite element-based simulator to study the fluid dynamic and crystal growth of this inner/outer flow independently controlled showerhead. Two simulation experiments were performed. One experiment has demonstrated that both growth rate and Ga yield can be improved without compromising the uniformity by controlling the different input parameters of inner and outer flow on the showerhead, as compared with the conventional showerhead. The other experiment has demonstrated that the showerhead can be further optimized by changing the inner/outer area ratio and input parameters.

(Invited) Nanostructured Materials for Higher Energy and Higher Power Lithium-Ion Batteries

Energy density and cost of Li-ion batteries (LIBs) based on conventional intercalation compounds are closely approaching their limits. The reliance of conventional cathodes on the use of toxic metals additionally endangers health and safety of miners in developing countries. Conversion-type active materials offer an opportunity to double energy stored in LIBs, reduce their cost by the same factor, and improve cell safety. These materials may be produced from safer, cheaper and globally available resources and contribute to accelerated adoption of electric vehicles (EVs). Critically important for the adoption by LIB manufacturing industry, novel materials must serve as drop-in replacements and be fully compatible with existing electrode and cell assembling technologies. Their use should not require additional steps or modified procedures, which often increase production cost and most importantly induce highly-undesired safety or yield risks. As such, all the critical limitations of novel conversion-type materials (large volume changes, undesirable interactions with electrolyte, mechanical instability, slow ion transport, slow electron transport, etc.) should be resolved on the individual particle level via formation of nanocomposites. In order to enable sufficiently low synthesis cost, such nanocomposite particles should be produced using the low-cost bulk reactors and well-established powder production methodologies. Such a strategy enabled success of Sila Nanotechnologies, Inc. to develop and commercialize production of silicon (Si) - based anode materials that experience minimal volume changes and remarkable electrochemical stability during cycling in matched full cells of various sizes.

Load-Bearing Capacity and Deformation of Jammed Architectural Structures

Abstract The Jammed Architectural Structures (JAS), presented in this article, are 3D-printed fully reversible architectural elements, composed of low-cost loose bulk material, and string reinforce...

Fully spherical stretchable silicon photodiodes array for simultaneous 360 imaging

Imaging is one of the important wonders of today's world. While everyday millions of snaps are taken, new advances like panoramic imaging have become increasingly popular. However, as of today an imaging system which can simultaneously capture images from all 360° viewpoints with a single sensor has not been achieved. Here, we show a physically flexible and stretchable version of arrayed silicon photodiodes made from low-cost bulk monocrystalline silicon (100) that can capture simultaneous omnidirectional images. The present report, with multiple wavelength detection, fast photoresponsivity, a wide viewing angle, selective aberration, and dynamic focusing enabled by 3D printed pneumatic actuators (note, today millions of image sensors can be integrated in mm2 area), overcomes previous demonstrations of only hemispherical photodetection capability. Such imaging capability will make unmanned air vehicles or self-driven cars safer, affordable augmented and virtual reality and more importantly, in-vivo biomedical imaging will be more effective.

A study on the performance of piezoelectric composite materials for designing embedded transducers for concrete assessment

Ultrasonic measurements of concrete can provide crucial information about its state of health. The most common practice in the construction industry consists in using external probes which strongly limits the use of the method since large parts of the in-service structures are difficult to access. It is also possible to assess in real time the setting process of the concrete using ultrasonic measurements. In practice, the field measurement of the concrete hardening is limited by the formworks. As an alternative, some research teams have studied the possibility to directly embed the transducers into the concrete structures. The current embedded ultrasonic transducers are of two categories: bulk piezoelectric elements surrounded by several coating and matching layers and composites piezoelectric elements. Both technologies aim at optimizing the wave energy transmitted to the tested medium. The performances of the transducers of the first kind have been studied in a previous study. A fair amount of recent research has been focused on the development of novel cement-based piezoelectric composites. In this study, we first compare the effective properties of such cement-based materials with more widespread composites made with matrices of epoxy resins or polyurethane. The study only concerns the 1–3 fiber arrangement composites. The effective properties are computed using both an analytical mixing rule method and a finite element based homogenization method using representative volume elements (RVEs) which allows for considering more realistic fiber arrangements, leading yet to very similar results. The effective piezoelectric properties of cement-based composites appear to be very low compared to composites made of epoxy or polyurethane. This result is underlined by looking at the acoustic response and the electric input impedance of different piezoelectric disks where we compare performances of such transducers with a low-cost bulk piezoelectric disc element. The first radial mode of the latter is responsible for an acoustic response of the same order of magnitude as those for the piezo-composites. This result confirms that the design of efficient low-cost embedded ultrasonic transducers can be done with such piezoceramic disks.

Integration and Electrical Properties of Ferroelectric Hf0.5Zr0.5O2 Thin Film on Bulk β-Ga2O3(-201) Substrate for Memory Applications

Metal–ferroelectric–insulator–semiconductor (MFIS) structures with wide bandgap semiconductors are promising for high temperature, radiation-hard, and high-density memory applications, but the insufficient scalability of perovskite-based ferroelectric thin films and the high cost of conventional wide bandgap semiconductors are the most serious barriers for their practical applications. Here, we integrate highly scalable ferroelectric Hf0.5Zr0.5O2 (HZO) thin films on potentially low-cost bulk $\beta$ -Ga2O3substrates using an Al2O3 buffer layer to form MFIS structures and investigate the microstructural and electrical properties of the HZO thin films and TaN/HZO/Al2O3/ $\beta$ -Ga2O3(−201) MFIS structures. We find that the TaN/HZO/Al2O3/ $\beta$ -Ga2O3(−201) MFIS structure annealed at 550 °C exhibits a memory effect, which is attributed to the ferroelectricity of the HZO thin film. This letter represents the critical first step in the implementation of $\beta$ -Ga2O3in HfO2-based ferroelectric memories.

Bulk combinatorial analysis for searching new rare-earth free permanent magnets: Reactive crucible melting applied to the Fe-Sn binary system

The reactive crucible melting method is known to be an efficient and low-cost bulk combinatorial synthesis technique to search for new phases. In this work, we tested this technique by investigating the Fe-Sn binary system. For high-throughput characterization, this synthesis technique was combined with energy dispersive x-ray spectroscopy as well as magneto-optical Kerr microscopy. The latter was used for identification of desired phases with uniaxial magnetic anisotropy. Reliability of the reactive crucible method was evaluated by comparison of the phase composition forming in the reactive crucible with phases appearing in conventionally melted samples and with the phases represented in the reported Fe-Sn phase diagram. It was found that the Fe5Sn3 phase, existing in the equilibrium phase diagram at 800 °C and forming in conventionally melted alloys, does not exist in the diffusion zone of the reactive crucible. The problem of ‘missing phases’ is discussed. In addition, we have shown that the anisotropy energy obtained by quantitative analysis of the uniaxial domain structure of Fe3Sn2 phase, gives the value of 1 MJ/m3, whereas K1 evaluated by conventional magnetometry is ∼ 0.07 MJ/m3 only, by this demonstrating how erroneous the assessment of K1 from domain structure can be. Finally, a new unit cell is proposed for Fe5Sn3 phase, which is commensurately modulated by the orthorhombic unit cell with lattice parameters of a = 4.221 Å, b = 7.322 Å, c = 5.252 Å and the space group Pbcm(α00)0s0 with a modulation vector of q = (½,0,0).

Experimental Investigation and Analysis of Ecofriendly Compression Molded Woven Plant Fibre Polyester Composite

Polymer matrix composites are widely applied for the manufacturing of components employed in hostile environments to increase the service life and sometimes at a later stage for the reclamation of worn out parts. Every decade, numerous materials and techniques are being introduced and developed for the effective protection of low cost bulk materials out of which the fabrication of components could be done. Among such techniques hand layup, matched die mould methods, contact mould methods, filament winding and pultrusion methods has being employed increasingly in the process industries which has several significant advantages over other processes. It has become a process of its reliability, better process control, ease of use, good surface finish and closeness of dimensions. One among the method matched die mould method was selected as the process of preparation of the composite plate in the presented work. However, there are some inherent problems with control of resin flow, application of high temperature for curing during fabrication process. To address those main problems, a systematic investigation was carried out. The selected material is natural plant fibre available in abundant called “Crotalaria juncea” and is being employed as a green manuring plant in agriculture. In the investigation, the fibre is taken in two different forms of random and woven orientations and plate fabrication is done with unsaturated polyester resin as the matrix. The investigation is on woven orientation of biaxial, biaxially stitched and unidirectional woven types were done using the fibre to the size of the plate to be fabricated. Woven fibres of these three types were done at fibre design centre, Kerala. It was found that the fabrication could be done by placing two layer and three layer of the woven mat alone. So for the three woven types, two layer and three layer plates were fabricated to give about six plates in total. Here again to arrive at a closeness value for each combination, three plates were fabricated and the average value is got by testing. Tensile, flexural, impact and shear testing was done on all the plates as per ASTM standards and the responses were noted and plots were drawn and studied for the orientation for which the material possessed best property. The second part of the study was, with the experimental results got from the woven orientation, analysis was done by ANSYS and LS-DYNA software for the mechanical property and the responses got, was matching with the experimental testing methods and found that both the results were nearly the same thereby optimizing the results achieved. This is presented in detail in the forth coming chapters. The studies revealed that the fibre parameters taken had a significant influence on the mechanical properties. It was found that at a particular weight fraction the mechanical properties achieved the highest values in case of random orientation and particular woven orientations in case woven types. The increase in layers also had an influence over the property of the material. This composite prepared also initiates us in preparing newer composites with existing natural fibers, which haven’t been yet explored and which can reduce the cost. This gives way also in preparation of the same and releasing a newer variety of material to the Engineering industry which can be suited for some required application.