Micron Size Research Articles

The emission and physicochemical properties of airborne microplastics and nanoplastics generated during the mechanical recycling of plastic via shredding

This study examined the emission and physicochemical properties of microplastics and nanoplastics (MPs/NPs) generated during shredding, which is regularly used in mechanical recycling. Waste and new polyethylene terephthalate, polypropylene, and high-density polyethylene were investigated herein for a total of six categories. The concentration and size distribution of particles were measured using two spectrometer instruments, and morphology and elemental composition of emitted particles were analyzed with microscopy and spectroscopy. This study found that number concentrations in both submicron and micron sizes of respirable particles were 3–2910× higher during periods of shredding than pre-shredding background concentrations. Maximum concentrations of particles within 10–420 nm, across all six categories, ranged from 22,000- to 1,300,000-particles/cm3 during shredding, compared to average background levels of 700 particles/cm3. Maximum concentrations of particles within 0.3 to 10 μm, across all six categories, ranged from 24- to 2000-particles/cm3 during shredding, compared to average background levels of 2 particles/cm3. Waste plastics consistently generated higher emissions than their new counterparts, which is attributed to the labels, adhesives, and increased additives incorporated into the waste plastic. Morphology varied drastically between particles and an elemental composition analysis found that the samples consisted primarily of C and O, representing the polymer material, as well as Na, Mg, Al, Si, Cu, Cl, K, Ca, Ti, Fe, Rb, and Br representing additives, label, and other contaminates. The shredding of plastic has the potential to expose workers to elevated concentrations of airborne MPs/NPs, especially those between 10 and 100 nm.

Sol-gel synthesis, structure and adsorption properties of LiMgxMn(2-x)O4 (0 ≤ x ≤ 0.7) Oxides

Lithium manganese оxides with a spinel structure LiMgxMn(2–x)O4, doped with Mg2+ ions in the range 0 ≤ x ≤ 0.7, were obtained by sol-gel synthesis. Phase composition and morphology of obtained оxides were studied by using X-ray phase analysis and scanning electron microscopy. It is shown, that in the studied range 0 ≤ x ≤ 0.7 Mg-doped lithium manganese оxides saved the structure of the original cubic spinel LiMn2O4, while an increase in parameter a was observed from 8.175 to 8.309 Å and average crystallite size practically unchanged (30–36 nm). Samples of the initial LiMn2O4 and Mg-doped spinels were represented by prismatic particles of submicron (0.1–0.2 µm) and micron (1.0–3.0 µm) sizes, respectively. The effect of the adsorbent dose (0.05–0.3 g/l) and pH (3.0–13.0) of the solution on the adsorption efficiency was studied. The adsorption isotherms of the LiMg0.3Mn1.7O4 samples were described by the Langmuir monomolecular adsorption equation. An increase in the temperature of the model solution from 25 to 45°C was accompanied by an increase in the maximum adsorption of the LiMg0.3Mn1.7O4 samples from 10.50 to 10.98 mmol/g, which indicates the endothermic nature of the adsorption process. The kinetics of adsorption was well described by a pseudo-second order equation, which indicates the occurrence of chemical interaction during the adsorption process.

Uniaxial Molecular Alignment in Thin Films Composed of Discrete NDI‐T2 Oligomers Investigated by Variable‐Angle Spectroscopic and Imaging Ellipsometry

The understanding of the optical characteristics and the influence of thermally induced crystallization is vital to evaluate newly synthesized organic semiconductors for their potential applications. Variable‐angle spectroscopic ellipsometry (VASE) is employed to determine the complex dielectric function of two recently developed discrete oligomers based on naphthalene diimide (NDI) and bithiophene (T2), applying an anisotropic optical model. It is shown that the as‐cast films are optically near‐isotropic, while the annealed films exhibit pronounced anisotropies with respect to the orientation of the π−π* transition. Differences between the two distinct molecules are observed and discussed. The degree of optical anisotropy is quantified using the average molecular orientation angle φ, associated with the orientation of the π−π* transition dipole, and the related orientation order parameter S. The molecules are shown to form crystallites of several microns in size upon annealing. Imaging ellipsometry is thus additionally employed to study their optical anisotropy on a microscopic scale, and the agreement with results from macroscopic measurements is evaluated.

Formation of flake-like DAAF crystals with tunable size realized on a microfluidic platform for binder-free initiator explosives

Flake-like energetic crystal has a great potential to achieve initiator explosive with high reactivity, low initiation threshold, high safety, and facile post-processing, but it has been limited for 3,3′-diamino-4,4′-azoxyfurazan (DAAF) by the difficulties in controlling crystal morphology. Here reported is a microfluidic preparation of flake-like DAAF crystals (f-DAAF) with tunable size by combined effect of the adding of facet-controlling agent (nigrosin alcohol soluble) and tuning of the external crystallization conditions. The results show that the crystal system of f-DAAF belong to monoclinic system, the (−201) facet is the largest exposed face. The f-DAAF possess high crystallinity, tunable flake aspect ratio from 6.15 to 66.8 and specific surface area from 2.57 to 5.67 m2·g−1. Molecular dynamics simulations were performed to investigate the selective interactions between the two molecules (facet-controlling agent and solvent) and different crystal faces of DAAF in a real experiment environment. Combined with the experimental results, a possible growth mechanism of the flake-like morphology was discussed. It is found that the f-DAAF not only possess lower impact sensitivity itself, but also can reduce the impact sensitivity of other explosives with high impact sensitivity. The electric explosion derived flyer initiation experiments show that the initiation sensitivity of f-DAAF is much lower than that of raw DAAF in micron size, and comparable to that of ultrafine DAAF. This work demonstrates the promising application potential of f-DAAF as high-performance initiator explosives with low initiation threshold and high safety, and also provides an effective way for their preparation.

Ultrasensitive detection of cancer-associated nucleic acids and mutations by primer exchange reaction-based signal amplification and flow cytometry

The detection of cancer-associated nucleic acids and mutations through liquid biopsy has emerged as a highly promising non-invasive approach for early cancer detection and monitoring. In this study, we report the development of primer exchange reaction (PER) based signal amplification strategy that enables the rapid, sensitive and specific detection of nucleic acids bearing cancer specific single nucleotide mutations using flow cytometry. Using micrometer size beads as support for immobilizing oligonucleotides and programmable PER assembly for target oligonucleotide recognition and fluorescence signal amplification, we demonstrated the versatile detection of target nucleic acids including KRAS oligonucleotide, fragmented mRNAs, and miR-21. Moreover, our detection system can discriminate single base mutations frequently occurred in cancer-associated genes including KRAS, PIK3CA and P53 from cell extracts and circulating tumor DNAs (ctDNAs). The detection is highly sensitive, with a limit of detection down to 27 fM without pre-amplification. In view of a clinical application, we demonstrate the detection of single mutations after extraction and pre-amplification of ctDNAs from the plasma of breast cancer patients. Importantly, our detection strategy enabled the detection of single KRAS mutation even in the presence of 1000-fold excess of wild type (WT) DNA using multi-color flow cytometry detection approach. Overall, our strategy holds immense potential for clinical applications, offering significant improvements for early cancer detection and monitoring.

Signatures of bulk neutrinos in the early Universe

Neutrino masses and quantum gravity are strong reasons to extend the standard model of particle physics. A large extra dimension can be motivated by quantum gravity and can explain the small neutrino masses with new singlet states that propagate in the bulk. In such a case, a Kaluza-Klein tower of sterile neutrinos emerges. We revisit constraints on towers of sterile neutrinos that come from cosmological observables such as the effective number of noninteracting relativistic species and the dark matter density. These limits generically rule out micron-sized extra dimensions. We explore the weakening of these constraints to accommodate an extra dimension close to the micron size by assuming that the Universe is reheated after inflation to a low temperature. We discuss how such a possibility can be distinguished in the event of a positive signal in a cosmological observable. Published by the American Physical Society 2024

Al(Si)/Al2O3 and NiAl(Si)/Al2O3 co-continuous composites obtained by low temperature Reactive Metal Penetration of dense silica preforms.

Interpenetrating network Al(Si)/Al2O3 composites, obtained by a reactive metal penetration process, where pure aluminum metal reacts with a dense amorphous silica preform, are an interesting class of metal/ceramic composites, with two continuous networks of metal (Al-Si alloy) and ceramic (Al2O3). These composites have high stiffness and hardness, while retaining acceptable toughness and good thermal and electrical conductivity, and can be used in wear or thermal management applications. A second infiltration step with nickel allows to substitute the Al(Si) alloy with an intermetallic, obtaining an interpenetrating network NiAl(Si)/Al2O3 composite, with very high hardness and melting point. While in the standard process the temperature for obtaining the Al(Si)/Al2O3 composites is in the 1100-1200 °C range, in this paper we studied instead the 700-1000 °C temperature range and its effect on the microstructure of the final NiAl(Si)/Al2O3 composite. After the first infiltration step, the microstructure of Al(Si)/Al2O3 composites depends on both temperature and time of the treatment. At 700-800 °C and for reaction time of 1-2 hours, the grain size is completely sub-micrometric. When temperature and time of reaction increase, islands with a coarser microstructure, of micrometric size, form, reaching a fully micrometric coarser microstructure at 1100-1200 °C. The islands formation is due to the transformation from transition aluminas, formed at low temperature and low reaction time, to α-alumina, while at high temperature α-alumina forms directly. In a second step, the Al(Si) metal network was replaced with an intermetallic one, by contacting the composite with liquid nickel, that reacted with the Al(Si) alloy forming an Al-Ni-Si intermetallic. The temperature and duration of the first infiltration step strongly influences not only the microstructure of the Al(Si)/Al2O3 composite but also of the final NiAl(Si)/Al2O3 one, that is finer when the first step (reaction of aluminum with silica) occurs at lower temperature.

Low-cost and durable polyvinyl alcohol modified polyethylene separator for vanadium redox flow battery

Porous separators are considered a viable alternative to the high cost Nafion membrane for vanadium redox flow battery (VRFB) commercialization. However, the porous separators suffer from high vanadium ion crossover due to the presence of large micron size pores, which leads to decay in capacity of the VRFB system. To tackle the same, a composite separator is synthesized wherein a cross-linked polyvinyl alcohol (PVA) layer is coated on to the porous polyethylene silica separator (PE separator) to mitigate the vanadium ion crossover rate and employed in the VRFB application. Scanning electron microscopy (SEM) analysis confirmed the successful coating of the PVA film on to the PE separator. Synthesized PE-PVA separator showed a significant decrease in the vanadium ion crossover by 31.44 times compared to the pristine PE separator. Consequently, the self-discharge time increases by 8 and 1.66 times compared to the pristine PE separator and the Nafion117 membrane, respectively. VRFB cell equipped with the synthesized separator showed better capacity retention with a capacity fade rate of 0.2 % Ah·cycle−1 than the Nafion117 membrane (0.5 % Ah·cycle−1). In-situ and ex-situ oxidative stability of the separator is explored in detail and a degradation mechanism of the cross-linked PVA membrane is proposed accordingly. The synthesized single side coated PE-PVA´ separator exhibits higher coulombic efficiency of 99 % and comparable energy efficiency of 71 % at a current density of 120 mA·cm−2 and demonstrated excellent lifetime durability tested up to 1600 charge-discharge cycles at 80 mA·cm−2.

Dynamic Analysis of Laminated Composite with Inclusion

With growing environmental awareness, ecological concerns and new legislations, bio-fibre reinforced polymer composites have received increasing attention during the recent decades. This study focuses on the processing of seashell powder into micron size and utilizing the same as filler with glass fibres and epoxy resin in the preparation of the composite, thereby increasing mechanical strength. The constituents used in this composite showcase properties like higher strength, higher stiffness, chemical resistance, good insulation to electricity and lightweight. The components found in seashell such as Na, Ca, Al and C along with the S-glass fibre and the binding provided by the resin are responsible for enhancing hardness and tensile strength of the composite. Numerical analysis for the tensile test was done using ANSYS simulation for both composites with 5% filler (50% fibre + 45% resin+ 5% seashell) and without filler (50% fibre + 50% resin). Two laminate composites, with 5% filler (50% fibre + 45% resin+ 5% seashell) and without filler (50% fibre + 50% resin) were fabricated and their mechanical properties were compared using various tests like tensile and low velocity impact test with an impact velocity of 1 m/s, 2 m/s, 3 m/s and 4 m/s. The results from these tests were interpreted. The findings show that the specimen with 5% filler has more ultimate strength and impact strength when compared to the one without filler.

Separation of multicomponent gas mixtures

In the production of granular organo-mineral fertilizers using the fluidization technique by dehydrating heterogeneous liquids, as an energy-efficient technology, there is a need to purify the spent coolant containing solid particles, dust and a significant amount of water vapor. Solid particles up to 20 microns in size are effectively captured in cyclone devices. To further capture water vapor and fine solid particles, a scrubber is used with an additional circulation circuit involving an additional bone of water, which, upon reaching a concentration of more than 20%, is discharged back to the granulation stage. This leads to an increase in energy consumption for production in general. Condensation of vapors in a dispersion containing 5-7% (w/w) moisture in the form of water vapor at the second stage of purification will increase the level of environmental safety in production. To select an innovative method of separation of multicomponent gas dispersions accompanied by a change in the aggregate state and a rational design of the apparatus, a review of scientific articles and developments such as systematization of existing methods was carried out. Such an approach makes it possible to choose the optimal solution for the separation of gas-dust and gas-liquid flows in the conditions of the existence of a large number of types of equipment design and the level of their innovation. In addition to the rational design of the devices, great attention was also paid to the issues of energy efficiency, resource saving and ensuring the state of environmental safety at production facilities in the conducted research. Based on the results of the analysis, it is proposed to use a scheme of consecutively installed cyclones CN-11 and SK‑CN-33. It is proposed to use the ЦН-11 cyclone for the preliminary capture of highly dispersed dust, and the SK-CN‑33 for condensation and capture of water vapor and solids not caught in the previous cyclone particles.

Microstructural Characterization of Friction Stir Welds of Aluminum 6082 Produced with Bobbin Tool.

This study utilized a bobbin tool to friction stir weld aluminum 6082 workpieces under two sets of process parameters: a tool rotation speed of 280 rev/min with a weld velocity of 280 mm/min (280/280) and a tool rotation speed of 450 rev/min with a weld velocity of 450 mm/min (450/450). The weld microstructures were characterized through optical microscopy utilizing polarized light and through transmission electron microscopy (TEM) and scanning electron microscopy (SEM) coupled with chemical analysis by energy dispersive spectroscopy and electron back scatter diffraction. The microstructural studies were supplemented by hardness measurements (Vickers) performed on the same sections as the metallographic examinations. The produced weldments were free from cracks and any discontinuities. Fine, equiaxed grains that were several microns in size characterized the stir zones (SZs), and the advancing (AS) and retreating (RS) sides revealed distinct microstructural features. On the AS, the transition from the thermo-mechanically affected zone to the SZ was well defined and sharp, but on the RS, the transition appeared as a continuous, gradual change in microstructure. The lower weld energy (280/280) produced lower hardness in the stir zone than the higher energy weld (450/450), ~95 HV1 versus ~115 HV1; however, the 280/280 welds showed higher tensile strengths than the 450/450 welds, ~238 MPa as opposed to ~172 MPa. These behaviors in mechanical performance correlated with the temperature histories produced by each set of weld parameters in relation to the precipitation behavior of the alloy. The fracture characteristics of the weldments were notably different with the 450/450 sample fracturing in a quasi-brittle manner with slight plastic deformation and the 280/280 sample fracturing ductilely. A numerical simulation supported the investigation by elucidating the temperature and material flow behavior during the joining process.

Single Crystalline GeSe Van Der Waals Ribbons With Uniform Layer Stacking, High Carrier Mobility, and Adjustable Edge Morphology.

Performance of the group IV monochalcogenide GeSe in solar cells, electronic, and optoelectronic devices is expected to improve when high-quality single crystalline material is used rather than polycrystalline films. Crystalline flakes represent an attractive alternative to bulk single crystals as their synthesis may be developed to be scalable, faster, and with higher overall yield. However, large - and especially large and thin - single crystal flakes are notoriously hard to synthesize. Here it is demonstrated that vapor-liquid-solid growth combined with direct lateral vapor-solid incorporation produces high-quality single crystalline GeSe ribbons with tens of micrometers size and controllable thickness. Electron microscopy shows that the ribbons exhibit perfect equilibrium (AB) van der Waals stacking order without extended defects across the entire thickness, in contrast to the conventional case of substrate-supported flakes where material is added via layer-by-layer nucleation and growth on the basal plane. Electrical measurements show anisotropic transport and a high Hall mobility of 85 cm2V-1s-1, on par with the best single crystals to date. Growth from mixed GeSe and SnSe vapors, finally, yields ribbons with unchanged structure and composition but with jagged edges, promising for applications that rely on ample chemically active edge sites, such as catalysis or photocatalysis.

Fluorine-free superhydrophobic surfaces by atmospheric pressure plasma deposition of silazane-based suspensions

Atmospheric plasma is used to deposit superhydrophobic fluorine-free thin films onto a substrate. In this process, a suspension of micron size silica particles in a silazane based precursor is deposited in a single step using a dielectric barrier discharge plasma jet moving above the substrate. Thanks to an optimized configuration between the suspension injection and the plasma jet, the silazane precursor can be polymerized on the substrate surface but also, on silica particles to form additional micro size particles. The experimental parameters for optimal deposition are discussed, with emphasis on those leading to the formation of this dual roughness surface caused by the arrangement of both silica particles and particles generated from the precursor plasma polymerization. The combination of these two different length scales for the roughness leads to a decreased wettability of the coated substrate and a water contact angle larger than 150°.

Bio-MOFs based on natural phenolic, hematoxylin leverages biomedical applications: enzyme inhibition, antioxidant, and antibacterial properties.

Here, using natural hematoxylin (HT) as linker, metal-organic frameworks (MOFs) from Cu(II), Fe(II), and Fe(III) ions was prepared. The SEM images and DLS analyses revealed HT-based MOFs are <micrometer sizes with the highest surface area value of 49.2 m2/g for HT-Fe(III) MOFs. Interestingly, HT-based MOFs exhibit fluorescent properties at λem=330 nm with fluorescence intensities of 11485, 2120, and 6790 (a.u) for HT-Cu(II), Fe(II), and Fe(III) MOFs, respectively. Moreover, HT-based MOFs inhibited α-glucosidase enyzme in a concentration-dependent manner e.g., 33.1%, 69.8%, and 59.7% of Cenzyme=500 mg/mL was inhibited by HT-Cu(II)-MOF, HT-Fe(II)-MOF, and HT-Fe(III)-MOFs, respectively. The minimum bactericidal concentration (MBC) values of HT-Cu(II) MOFs for Escherichia coli (gram -), Staphylococcus aureus (gram +), and Candida albicans are determined as 5, 5, and 10 mg/mL, respectively. Also, the antioxidant activities of 250 ppm HT-based MOF based on total phenol content (TPC) tests revealed 279, 208, 124, and 152 mg.gallic acid equivalent/mL (mg GA equivalency/mL) for HT, HT-Cu(II) MOF, HT-Fe(II) MOF, and HT-Fe(III), respectively affirming that antioxidant properties were retained. Moreover, HT-Fe(II) and HT-Fe(III) MOFs (62.5 µg/mL) against human null-1 lung cell line revealed cell viabilities of 98.7±12.2% and 88.9±11.7%, respectively as concentration-dependent biocompatibility of MOFs.

Performance of construction and demolition waste as recycled aggregates in concrete - a review

This article presents a structured and comprehensive review of the existing literature on physical, chemical, microstructure, and durability properties of recycled aggregate concrete (RAC). The engineering properties of concrete made from such recycled aggregates are critically analyzed by focusing mainly on the fresh and hardened states along with several characterization techniques such as SEM, EDX, XRD, FTIR and TG-DTA. Also, creep and shrinkage, the microstructure and durability of recycled aggregate concrete (RAC) were studied and evaluated critically. In addition, improvement techniques in its microstructure are also explored with efficient mixing approaches for the development of geopolymer recycled aggregate concrete. Furthermore, techniques to enhance the mechanical characteristics and long-term performance of recycled aggregate are distilled and divided into three categories: (1) lowering the porosity of recycled aggregate, (2) lowering the layer of old mortar on the surface of recycled aggregate, and (3) enhancing the property without changing the recycled aggregate. It is evident from the thorough examination that recycled aggregates can be used in concrete up to a certain amount. For the creation of sustainable and high-performance concrete, it is also necessary to incorporate mineral admixtures of micron, sub-micron, and nano size to address the drawbacks of recycled aggregates.

Micrometer-Scale Graphene-Based Liquid Cells of Highly Concentrated Salt Solutions for In Situ Liquid-Cell Transmission Electron Microscopy.

In situ liquid-cell transmission microscopy has attracted much attention as a method for the direct observations of the dynamics of soft matter. A graphene liquid cell (GLC) has previously been investigated as an alternative to a conventional SiN x liquid cell. Although GLCs are capable of scavenging radicals and providing high spatial resolutions, their production is fundamentally stochastic, and a significant compositional change in liquids encapsulated in GLCs has recently been pointed out. We found that graphene-based liquid cells were formed in nano- to micrometer sizes with high reproducibility when the concentration of the encapsulated aqueous salt solution was high. In contrast, when we revisited conventional fabrication methods, water-encapsulated GLC was formed with low yield, and any electron diffraction spots from ice were not confirmed by a cooling experiment. The reason for this was the presence of intrinsic defects in the graphene, the presence of which we confirmed by the etch-pit method. The shrinkage of a water-encapsulated cell and a decrease in the bubble area in an aqueous (NH4)2SO4 solution cell suggested that volatile water molecules and gas molecules can leak from the cells during the fabrication and observation processes. Further revision of the conditions for the formation of liquid cells and a reduction in the number of intrinsic graphene defects are expected to lead to the provision of graphene-based liquid cells capable of encapsulating dilute aqueous solutions or pure water.

Microheater Controlled Crystal Phase Engineering of Nanowires Using In Situ Transmission Electron Microscopy

AbstractCrystal Phase Quantum Dots (CPQDs) offer promising properties for quantum communication. How CPQDs can be formed in Au‐catalyzed GaAs nanowires using different precursor flows and temperatures by in situ environmental transmission electron microscopy (ETEM) experiments is studied. A III‐V gas supply system controls the precursor flow and custom‐built micro electro‐mechanical system (MEMS) chips with monocrystalline Si‐cantilevers are used for temperature control, forming a micrometer‐scale metal–organic vapor phase epitaxy (µMOVPE) system. The preferentially formed crystal phases are mapped at different precursor flows and temperatures to determine optimal growth parameters for either crystal phase. To control the position and length of CPQDs, the time scale for crystal phase change is investigated. The micrometer size of the cantilevers allows temperature shifts of more than 100 °C within 0.1 s at the nanowire growth temperature, which can be much faster than the growth time for a single lattice layer. For controlling the crystal phase, the temperature change is found to be superior to precursor flow, which takes tens of seconds for the crystal phase formation to react. This µMOVPE approach may ultimately provide faster temperature control than bulk MOVPE systems and hence enable engineering sequences of CPQDs with quantum dot lengths and positions defined with atomic precision.

The Difference between Traditional Magnetic Stimulation and Microcoil Stimulation: Threshold and the Electric Field Gradient

This paper considers the threshold value of the activating function needed for stimulation in traditional magnetic stimulation and microcoil stimulation. Two analyses of excitation have been studied: spatial frequency analysis and active membrane analysis using the Hodgkin−Huxley model. The activating function depends on the spatial distribution of the electric field gradient in the active membrane analysis and the spatial frequency in the spatial frequency analysis. Both analyses show that a microcoil (tens of microns in size) has a higher threshold than a traditional coil (tens of millimeters in size) when the spatial frequency is large or the spatial extent of the activating function is small. Consequently, the stimulation threshold for a microcoil is much higher than that for a conventional coil.

Quantification of delamination resistance data of FRP composites and its limits

Quantitative delamination resistance data of fibre-reinforced polymer-matrix (FRP) composites for quasi-static or cyclic fatigue loads are determined under different loading modes and load rates, respectively. Such data find use, e.g., in FRP materials’ development, materials’ selection, assessment of durability, or structural design. Round robins during test development yielded repeatability and reproducibility (coefficients of variation) of roughly 10 to 25%. This scatter has several different sources. Intrinsic material variability amounts to a few percent at best, at least for advanced manufacturing processes. This intrinsic scatter is essential for material comparisons and structural design. Measurement resolution specified in standardised test procedures yields a maximum of 4–5% variability. Most of the remaining scatter comes from other, extrinsic sources. Test operator actions, e.g., choice of test set-up, manual data acquisition or data analysis can yield extrinsic scatter. Damage mechanisms during delamination initiation and propagation act on the micro- and meso-scale, typically a few micrometer to a few hundred micrometer in size, with corresponding time-scales estimated to between a few tens of nanoseconds and a few microseconds. Defect size-scales are hence several orders of magnitudes lower than test specimen and structural scales, respectively. Predictive capability of models using such test data for structures are, therefore, limited. Major issues are up-scaling from straight beam-like specimens to larger shell-like structures, possibly with complex shape and varying thickness as well as from unidirectional fibre orientation to multidirectional lay-ups.

Supramolecular Hybrids of Proteins from Habu Snake Venom with Discrete [Pt(CN)4]2- Complex.

The venom of the Habu snake Protobothrops flavoviridis (P. flavoviridis) is known to contain a diverse array of proteins and peptides, with a notable presence of phospholipase A2 (PLA2) enzymes. These PLA2 enzymes have been extensively studied for their function and molecular evolution. Nevertheless, several aspects, such as the physical properties and the self-assembly mechanism of hierarchical structure from the nanoscale to the microscale with different chemical compounds, remain poorly understood. This study aims to fill this knowledge gap by investigating the behavior of enzyme components purified from P. flavoviridis venom in the presence of anionic [Pt(CN)4]2- complexes, which have the potential for soft metallophilic interactions and interesting optical properties. The purified PLA2 isozymes were diluted in Dulbecco's phosphate buffered saline (D-PBS (-)) and combined with the anionic metal complex, resulting in the formation of microstructures several micrometers in size, which further grew to form fibrous structures. This novel approach of combining PLA2 enzymes with discrete functional metal complexes opens up exciting possibilities for designing flexible and functional supramolecular and biomolecular hybrid systems in aqueous environments. These findings shed light on the potential applications of snake venom enzymes in nanotechnology and bioengineering.