Fish Scales Research Articles

Experimental study on heat transfer characteristics of R245fa pool boiling outside horizontal tubes

Full-liquid evaporator is an important part of the Organic Rankine Cycle (ORC). It is of great guiding significance to study the pool boiling heat transfer characteristics (high-temperature level) of the evaporator heat exchange tube for evaporator design. The pool boiling heat transfer characteristics (high-temperature level) of working fluid R245fa outside smooth tube and fish-scale tube are analyzed. The outcomes exhibit that the overall Heat Transfer Coefficient (HTC) of the smooth tube is 1.9–3.9 kW m−2 K−1, and the fish-scale tube is 3.8–4.3 kW m−2 K−1 when the saturation temperature of organic working medium R245fa is 80.5 °C. The HTC outside the fish scale tube is 1.45–3.13 instances that of the smooth tube. The external HTC of the smooth tube and fish-scale tube increases with the increase of heat flux, but the strengthening rate decreases. After the outer wall of the heat exchange tube used in the ORC evaporator is strengthened, the water velocity in the tube increases, which can not only strengthen the heat exchange in the tube but also play an anti-scaling effect.

Ag nanoparticle-embedded fish scales as SERS substrates for sensitive detection of forever chemical in real samples

Biological materials with unique surface properties provide a new avenue for fabricating green and sensitive SERS-active substrates. Herein, we present a simple but efficient method to prepare surface-enhanced Raman scattering (SERS) substrates by depositing silver nanoparticles (AgNPs) on fish scale substrates using an evaporation-induced self-assembly method (EISA). Characterization of the formed flexible Ag-impregnated substrate proved outstanding SERS sensitivity, uniformity, and reproducibility properties, with a Raman enhancement factor of 1.3 × 106 and a relative standard deviation of 6.4 %. Using this powerful fish scale substrate, a toxic environmental pollutant perfluorooctane sulfonamide (PFOSA) was indirectly detected in lake water, soil, and human urine samples. Due to its chemical structure, it is difficult to detect low concentrations of PFOSA in real samples. Interestingly, malachite green (MG) was smartly used as the Raman label for PFOSA detection in real samples. One of the main appeals is that the concentration of PFOSA can be correlated with a decrease in the SERS signal of MG in real samples. In conclusion, the strategy employed and reproducible SERS substrates may have diverse applications in clinical and environmental analyses.

Fish Scales for Wearable Patches: Tailoring Films Assembled From Fish Waste Gelatin, Carbon Dots and Chitin Nanocrystals

AbstractThe properties of gelatin and collagen extracted from fishery wastes, specifically from mullet (Mugil Cephalus) scales, are modified with the aim to achieve biocompatible films with tunable characteristics to design sustainable UV protection solutions in the healthcare sector. Different additives are used to the scope including plasticizers, cross‐linkers, surfactants and optical modifiers. Carbon dots (CDs) obtained from seabass (Dicentrarchus labrax) scales combined with polysorbate‐20 (PS) as a dispersant agent, enable the fabrication of materials capable of blocking UV radiation almost completely, a crucial feature for dermal contact applications. The addition of hydrophobic surfactants and crosslinkers as citric acid, chitosan and surface deacetylated chitin nanocrystals (CsNCs) allowed to modulate the water adsorption of the films in the range 3–30% and to reach a twofold and 4.5‐fold increase of tensile strength and elastic modulus, respectively, as compared to the neat gelatin film. Moreover, film thickness is shown to be another adjustable parameter to enhance optic, mechanical, and permeation properties: the higher the thickness, the greater the UV‐blocking properties, elongation‐at‐break and water vapor permeability, leading to films with attractive characteristics as wearable patches.

A review on the processing technique, physicochemical, and bioactive properties of marine collagen.

Collagens are conventionally derived from bovine and porcine sources. However, these sources were commonly associated with infectious diseases such as bovine spongiform encephalopathy, foot and mouth disease, autoimmune and allergic reactions, and religious constraints. The significant amount of collagen available in marine species, especially fish skins, scales, fins, and bones, shows that marine species can be a potential alternative source to mammalian collagen. Therefore, this review aims to give a clearer outlook on the processing techniques of marine collagen and its physicochemical and bioactive properties as a potential alternative to mammalian collagen. The two most suitable extraction methods for marine collagen are pepsin-soluble extraction and ultrasound-assisted extraction. Additionally, marine collagen's physicochemical and bioactive properties, such as antioxidants, wound healing, tissue engineering, and cosmetic biomaterial have been thoroughly discussed in this review. PRACTICAL APPLICATION: Collagen extracted from marine sources showed its potential in physicochemical and bioactive properties, including antioxidants and wound-healing capabilities, as an alternative to mammalian collagen. The significant amount of collagen found in marine species, particularly in fish skins, scales, bones, and sea cucumbers, suggests that marine sources could be a viable alternative to land mammal collagen due to their abundance and accessibility. The ultrasound-assisted extraction technique has improved the extracted marine collagen's physicochemical and bioactivity properties and quality properties.

Structural alterations in scales of Capoeta capoeta (Güldenstädt, 1773) from heavy metal-contaminated river water.

Heavy metal pollution, especially in freshwater, is a serious problem for aquatic organisms and human health. In this study, the scales of Capoeta capoeta living in the Karasu River (Turkey), which is estimated to be contaminated with pollutants, especially heavy metals, were examined for structural anomalies. Two stations on the river were selected for this purpose. Fish and surface water samples were taken at the stations. The heavy metal analyses were carried out in the water and the fish tissue. Heavy metal pollution was detected in the surface water. It was also observed that some heavy metals (As, Cu, Cd, Cr, Mn, Pb, Ni, Zn) accumulate in the fish tissue. Significant structural differences were observed on the dorsal surface of the scales, such as interrupted primary radii, damaged circuli, damaged focus, damaged anterior scale margin, broken focus, deformed scale structure, scattered chromatophores, dilatation of primary radii, loss of focus, damaged annuli, symmetry shift in the lateral line canal, eroded circuli, damaged posterior scale margin, double focus, branching in the primary radii, asymmetric circuli, incomplete annuli and interrupted secondary radii in each of the fish collected from the contaminated site. Heavy metals are suspected to be responsible for the structural anomalies in the scales. Based on these observations, it can be said that fish scales can be used as an effective indicator of water quality.

Study on microstructure and mechanical properties of 5052 aluminum alloy MIG welded joint for high-speed train

In this paper, the MIG welding process is utilized to weld a 3 mm thick 5052 aluminum alloy plate by using ER5356 welding wire as filler. The effects of different welding speeds on the microstructure and mechanical properties of the weld are systematically studied utilizing a metallographic microscope, x-ray diffractometer, scanning electron microscope, room temperature tensile, and microhardness. It was found that there were pore defects in the samples at lower or higher welding speeds, and there was no penetration at the maximum welding speed. When the welding speed is 650 mm min−1, the weld is well-formed, the surface is flat without pores, the fish scale is evenly distributed, and the weld shows good penetration. The intermetallic compounds of all the welds are mainly composed of α(Al), Mg2Si, Al3Fe, and Al3Mg2. The mechanical properties of the samples show that the hardness of the weld reaches the maximum value of 56.7HV at this welding speed, and the tensile strength and elongation are 210 MPa and 14.3%, respectively. The fracture is located at the junction of the base metal and the heat-affected zone, and the fracture type showed typical ductile fracture.

Exploring the vibration attenuation capabilities of fish surface mucus films: a novel biomimetic model for underwater vehicle drag reduction

Abstract This groundbreaking research delves into the ability of naturally occurring mucus films on fish surfaces to attenuate vibrations, utilizing nanomechanical systems for a comprehensive analysis. The mucus samples were collected from healthy Asian carp. We grouped the test subjects based on the varying durations of mucus adsorption on the fish scales: 1, 5, 10, and 30 minutes, with the bare scale serving as a benchmark. To evaluate the mucus film’s mechanical characteristics, we employed a nano-indentation tester, while a customized vibration excitation apparatus assessed its vibration attenuation capabilities. Our results indicate that the mucus film adheres to the fish scales via electrostatic forces, forming a smooth inner layer. As the adsorption time increases, the accumulation of additional proteins leads to a thicker outer layer. Remarkably, this outer layer exhibits significant vibration attenuation, assisting Asian carp in mitigating turbulence resistance and enhancing their swimming prowess.

Характеристики эласмоидной чешуи рыб и ее фракций, по данным ИК-Фурье-спектроскопии

Elasmoid scales of pike-perch (Sander lucioperca), white amur (Ctenopharyngodon idella), carp (Cyprinus carpio), freshwater bream (Abramis brama) and crucian carp (Carassius carassius) were processed without hydrolysis by “dry” method in order to study the characteristics of the obtained finished product, which determine its further use as additives for food and other purposes. The essence of the method consisted in washing the scales, its subsequent drying, grinding and separation, with obtaining two fractions enriched with both organic (cotton-like product) and inorganic (powder) components. FT-IR spectroscopy was used to characterize the scale samples and their enriched fractions. Characteristic bands known for collagen, in particular for Amide I, Amide II, Amide III, Amide A, were observed in the IR spectra of all the samples studied. The bands (inorganic part) at ~1022 cm–1 and at ~599 cm–1 indicate valence asymmetric vibrations of PO43– groups. Numerous bands for all experimental samples in the wavelength region 3900-3500 cm–1 can be caused by vibrations of OH groups, which is associated with the presence of water in the tested samples. Comparison of the absorption intensity in the region of characteristic frequencies of collagen and hydroxyapatite calculated by the IR method can be one of the approaches for the development of a rapid method for the determination of their quantitative content in fractions obtained from fish scales. Organic and mineral additives from fish scales can be recommended as components of formulations of various food products, as well as raw materials in tissue engineering, orthopedics and dentistry.

Extraction of Collagen from Fish Waste

The fishing industry in Ecuador has grown by 12%, generating more waste such as fish skins, bones, and scales. If not properly managed, this waste increases organic load, causing environmental problems. This research focuses on using two methods to extract collagen from fish scales.Objectives: The goal is to apply two methods for efficient collagen extraction from fish waste. Methodology: Two methods were explored: hydrolysis and demineralization, to obtain high-purity hydrolyzed collagen and denatured proteins to get partially hydrolyzed collagen. The raw material was characterized using the Micro Kjeldahl method to determine the protein and moisture content of scales from different fish species.Results: The yield was 60% and 39.72%, meeting physicochemical and microbiological requirements for human consumption, indicating that the processes used were efficient. Conclusions: Various collagen extraction procedures were analyzed, grouped into two methods: high-purity collagen and partially hydrolyzed collagen. The high-purity collagen method showed an unfavorable yield of 0.745%, while the partially hydrolyzed collagen method achieved a yield of 15.44%.

Heat treatments effects on Wear performance of Laser based Powder Bed Fusion fabricated Inconel 718 alloy

Among the AM processes Laser based Powder Bed Fusion (LPBF) technique offers precise and complex geometric fabrication. However, the microstructural and mechanical properties obtained from LPBF process requires further investigation, especially for IN718 superalloys. In this study, various heat treatments were applied to LPBFed Inconel 718 specimens to examine their effects on microstructure, microhardness and wear behavior. Three different heat treatments, each involving varied solutionizing and ageing steps were incorporated. As-printed specimens exhibited distinct fish scale structures with columnar dendrites. Heat treatments effectively dissolved the Laves phase and precipitated strengthening phases like γ′′ and γ′. Microhardness increased significantly after heat treatments, correlating with the formation of strengthening precipitates. Friction and wear tests showed as-printed specimens exhibited higher wear loss (922 ± 13 μm) and coefficient of friction (COF) (0.511 ± 0.07) due to the presence of Laves phase and softer matrix. Heat-treated specimens demonstrated significantly reduced wear loss (262 ± 5 μm) and COF (0.368 ± 0.01), with HT2 showing the best wear resistance attributed to a homogeneous microstructure. SEM analysis of worn surfaces confirmed abrasive and adhesive wear mechanisms in as-printed specimens, while heat-treated specimens exhibited reduced wear with smoother surfaces.

Marine Antioxidants from Marine Collagen and Collagen Peptides with Nutraceuticals Applications: A Review.

Collagen peptides and marine collagen are enormous resources currently utilized. This review aims to examine the scientific literature to determine which collagen peptides derived from marine sources and which natural active antioxidants from marine collagen have significant biological effects as health-promoting nutraceuticals. Marine collagen is extracted from both vertebrate and invertebrate marine creatures. For vertebrates, this includes fish skin, bones, scales, fins, and cartilage. For invertebrates, it includes mollusks, echinoderms, crustaceans, and poriferans. The method used involved data analysis to organize information for isolating and identifying marine biocompounds with antioxidant properties. Specifically, amino acids with antioxidant properties were identified, enabling the use of hydrolysates and collagen peptides as natural antioxidant nutraceuticals. The methods of extraction of hydrolyzed collagen and collagen peptides by different treatments are systematized. The structural characteristics of collagen, collagen peptides, and amino acids in fish skin and by-products, as well as in invertebrate organisms (jellyfish, mollusks, and crustaceans), are described. The antioxidant properties of different methods of collagen hydrolysates and collagen peptides are systematized, and the results are comparatively analyzed. Their use as natural antioxidant nutraceuticals expands the range of possibilities for the exploitation of natural resources that have not been widely used until now.

Fishwaste Derived Hydroxyapatite Nanostructure Combined with Black Rice Wine for Potential Antioxidant and Antimicrobial Response.

Hospital-acquired infection remains a serious threat globally, due to development of resistance to conventional antibiotics, which necessitates the urge for alternative therapy. Green nanotechnology has emerged as a holistic approach to address antibiotic resistance by combining environmental sustainability with improved therapeutic outcome. Nanostructure hydroxyapatite (HAP) has received significant attention in therapeutic and regenerative purposes due to its porous scaffold structure and biocompatible nature. In the present study, hydroxyapatite (HAP) nanoparticle was fabricated from the fish scale waste of red snapper fish. Black rice wine (BRW) was extracted from black rice commonly termed as Karupu kavuni/forbidden rice known for its nutritious effects. The present study focused on encapsulation of BRW within HAP nanoparticles (HAP@BRW) and evaluated its potential against nosocomial infections. Spectral and microscopic characterization of HAP@BRW revealed uniform encapsulation of BRW in HAP nanoparticles, aggregated irregular-shaped morphology of size 117.6nm. Maximum release of BRW (72%) within 24h indicates HAP as suitable drug delivery system suitable for biomedical applications. Antimicrobial studies revealed that HAP@BRW exhibited potent bactericidal effect against MRSA, MSSA, and Pseudomonas aeruginosa. Furthermore, HAP@BRW significantly inhibited the biofilm forming ability of MSSA and P. aeruginosa. Rich antioxidant property of HAP@BRW might be due to the presence of rich source of total polyphenolic, flavonoid, and anthocyanin content in BRW. In vitro and in vivo toxicity studies revealed biocompatible nature of HAP@BRW. Antibiofilm, antimicrobial, antioxidant, and biocompatible nature of HAP@BRW makes it a promising candidate for coating medical implants to avoid implant-associated infections and nosocomial infections.

Biomimetic materials research, from interest-driven to society-serving: an interview with Shu-Hong Yu

Abstract In August 2016, Shu-Hong Yu's group at the University of Science and Technology of China published an article in Science, reporting the first artificial nacre material obtained by imitating the growth process of natural nacre. The artificial nacre has a chemical composition and microstructure highly similar to that of natural nacre, and therefore is both strong and tough. Over the past two decades, Yu's team has been focusing on the field of biomimetic materials. In addition to shells and pearls, their mimetic targets also include wood, animal bone, fish scale, bamboo joint, lotus root silk and others. Their biomimetic materials have excellent mechanical properties and good application prospects in many fields. In this interview with NSR, Yu introduced many of his interesting works. His research was initially driven by interest and curiosity, but in recent years, he also hopes to shoulder more social responsibility as a scientist and benefit society with his research outputs.

Biomimetic Mineralized Hydroxyapatite-Fish-Scale Collagen/Chitosan Nanofibrous Membranes Promote Osteogenesis for Periodontal Tissue Regeneration.

Commercial mammalian collagen-based membranes used for guided tissue regeneration (GTR) in periodontal defect repair still face significant challenges, including ethical concerns, cost-effectiveness, and limited capacity for periodontal bone regeneration. Herein, an enhanced biomimetic mineralized hydroxyapatite (HAp)-fish-scale collagen (FCOL)/chitosan (CS) nanofibrous membrane was developed. Specifically, eco-friendly and biocompatible collagen extracted from grass carp fish scales was co-electrospun with CS to produce a biomimetic extracellular matrix membrane. An enhanced biomimetic mineralized HAp coating provided abundant active calcium and phosphate sites, which promoted cell osteogenic differentiation, and showed greater in vivo absorption. In vitro experiments demonstrated that the HAp-FCOL/CS membranes exhibited desirable properties with no cytotoxicity, provided a mimetic microenvironment for stem cell recruitment, and induced periodontal ligament cell osteogenic differentiation. In rat periodontal defects, HAp-FCOL/CS membranes significantly promoted new periodontal bone formation and regeneration. The results of this study indicate that low-cost, eco-friendly, and biomimetic HAp-FCOL/CS membranes could be promising alternatives to GTR membranes for periodontal regeneration in the clinic.

Research on Sea Trial Techniques for Motion Responses of HDPE Floating Rafts Used in Aquaculture

The innovative aquaculture equipment known as high-density polyethylene (HDPE) floating rafts has gained popularity among fishermen in the southeast coastal regions of China. Compared to deep-water anti-wave fish cages, the construction costs of HDPE floating rafts are 50% to 75% less. There is a dearth of comprehensive publicly available records of HDPE floating rafts sea trial data, despite substantial numerical studies on the motion response of aquaculture fish cages and scale model experiments under controlled-wave conditions. This study involves sea trial techniques under operational and extreme environmental conditions for motion responses of HDPE floating rafts, presents a comprehensive procedure for sea trials of HDPE floating rafts, summarizes the issues encountered during the trials, and suggests solutions. Using MATLAB for independent programming, motion videos and photos collected from the sea trials are processed for image capture, yielding the original time history curve of vertical displacement. Based on the sea trials’ data, including motion displacement, acceleration, mooring line force, overall deformation patterns, and current and wave data, recommendations are provided for the design and layout of HDPE floating rafts. Based on the Fast Fourier Transform (FFT) method for spectral analysis, the influence of interference items on the observational data is eliminated; the rationality of the observational data is verified in conjunction with the results of the Gabor Transform. This study offers a scientific analytical method for the structural design and safe operation of HDPE floating rafts and provides a reference for subsequent numerical simulations.

Study on ballistic impact performance of bionic fish scale protective armor

Composite bulletproof armor used in modern battlefield environments is mostly composed of ceramic/ultra-high molecular weight polyethylene (UHMWPE). In order to further improve its bulletproof performance, this study draws on the superposition of fish scales. The upper layer of the flexible protective armor consists of composite scale layers stacked on top of each other, and the lower layer consists of UHMWPE plates with grooved structures at the corresponding locations of the scales, where a single composite scale consists of an upper SiC ceramic layer and a lower UHMWPE layer. Finite element simulation is used to analyze the protective performance of the protective armor. The effects of back plate thickness, scale tilt angle, and impact location on the protection performance are investigated. The results show that the 8 mm thick back plate can effectively resist the impact of Type 53 7.62 mm armor-piercing incendiary ammunition, and the protective effect is best when the scale tilt angle is 30°. The maximum depression depth of the backplane is 12.4 mm, and the deformation of the backplane is reduced by 3 mm when the bullet hits the overlapping area of the scale compared with the central area of the target scale, accounting for 32.67% of the total deformation. The research work has guided the development of new bionic flexible protective armor.

Laser Ablating Biomimetic Periodic Array Fish Scale Surface for Drag Reduction.

Reducing resistance to surface friction is challenging in the field of engineering. Natural biological systems have evolved unique functional surfaces or special physiological functions to adapt to their complex environments over centuries. Among these biological wonders, fish, one of the oldest in the vertebrate group, have garnered attention due to their exceptional fluid dynamics capabilities. Fish skin has inspired innovation in reducing surface friction due to its unique structures and material properties. Herein, drawing inspiration from the unique properties of fish scales, a periodic array of fish scales was fabricated by laser ablation on a polished aluminum template. The morphology of the biomimetic fish scale surface was characterized using scanning electron microscopy and a white-light interfering profilometer. Drag reduction performance was measured in a closed circulating water tunnel. The maximum drag reduction was 10.26% at a Reynolds number of 39,532, and the drag reduction performance gradually decreased with an increase in the distance between fish scales. The mechanism of the biomimetic drag reduction surface was analyzed using computational fluid dynamics. Streamwise vortices were generated at the valley of the biomimetic fish scale, replacing sliding friction with rolling friction. These results are expected to provide a foundation for in-depth analysis of the hydrodynamic performance of fish and serve as new inspiration for drag reduction and antifouling.

Ecotoxicity and environmental safety assessment of two-dimensional niobium carbides (MXenes)

Two-dimensional (2D) MXenes have gained great interest in water treatment, biomedical, and environmental applications. The antimicrobial activity and cell toxicity of several MXenes including Nb4C3Tx and Nb2CTx have already been explored. However, potential side effects related to Nb-MXene toxicity, especially on aquatic pneuma, have rarely been studied. Using zebrafish embryos, we investigated and compared the potential acute toxicity between two forms of Nb-MXene: the multilayer (ML-Nb4C3Tx, ML-Nb2CTx) and the delaminated (DL-Nb2CTx, and DL-Nb4C3Tx) Nb-MXene. The LC50 of ML-Nb4C3Tx, ML-Nb2CTx, DL-Nb2CTx, and DL-Nb4C3Tx were estimated to be 220, 215, 225, and 128 mg/L, respectively. Although DL-Nb2CTx, and DL-Nb4C3Tx derivatives have similar sizes, DL-Nb4C3Tx not only shows the higher mortality (LC50 = 128 mg/L Vs 225 mg/L), but also the highest teratogenic effect (NOEC = 100 mg/L Vs 200 mg/L). LDH release assay suggested more cell membrane damage and a higher superoxide anion production in DL-Nb4C3Tx than DL-Nb2CTx,. Interestingly, both DL-Nb-MXene nanosheets showed insignificant cardiac, hepatic, or behavioral toxic effects compared to the negative control. Embryos treated with the NOEC of DL-Nb2CTx presented hyperlocomotion, while embryos treated with the NOEC of DL-Nb4C3Tx presented hyperlocomotion, suggesting developmental neurotoxic effect and muscle impairment induced by both DL-Nb-MXene. According to the Fish and Wildlife Service (FSW) Acute Toxicity Rating Scale, all tested Nb-MXene nanosheets were classified as “Practically not toxic”. However, DL-Nb4C3Tx should be treated with caution as it might cause a neurotoxic effect on fauna when it ends up in wastewater in high concentrations.

Review Paper on Properties of Concrete using Grind Fish Scale in Different forms Replacing Fine Aggregate and Cement

This study intends the use waste Fish scale powder as an alternative material for cement and fish scales as an alternative material for fine aggregates in concrete production. Different partial replacements of fish scale powder and fish scales (0%, 2%, 4%, and 6%) and (0%, 5%, 10%, and 15%) by volume of cement and fine aggregate are cast and test such as compressive strength is to be performed on concrete. Experimental research illustrates the enhancement of mechanical features in concrete due to the replacement of fish scale powder and fish scale concrete. A compression test will be carried out to evaluate the strength properties of concrete at the age of the 3rd, 7th, and 28th day

Formation and mechanical properties of AZ31B magnesium alloy welds by power-modulated oscillating laser

an energy-space modulated laser was proposed in welding workpieces with AZ31B magnesium alloy to enhance the efficiency of heat transfer and reduce defects of welds, and the proposed laser was power-modulated oscillating laser (PMOL). To validate the performance of the proposed technique, non-penetration welding and butt welding were conducted on the workpieces with a thickness of 5 mm. The impact of power-modulation parameters was investigated at the aspects of micro-structures, appearance, and mechanical properties of welds. The results showed that in comparison with a conventional laser (CL) or circular oscillation laser (COL), an energy-space modulated laser led to (1) an increased depth of weld penetration and (2) an enhanced coupling efficiency of laser energy. The parameters of power modulation could be optimized to reduce the defects of welds such as spatter, underfill, and thick fish scales significantly reduced; it refined the equiaxed grains in the center area of weld. When the frequency and amplitude of power-modulation were set as 50 Hz and 500 W, respectively, the mechanical properties of the weld were improved with the ultimate tensile strength of 238 MPa and an elongation ratio of 13.9 % which were 96.1 % and 58.7 % of those of the base material (BM), respectively. In comparison with the results welded by CL and COL, the ultimate tensile strength by PMOL was increased by 13.9 % and 4.4 %, and the elongation was increased by 54.4 % and 8.6 %, respectively.