Search Results (15)

Pharmaceutical packaging is one of the most used packaging types which contains aluminum and plastics. Due to increasing amounts of waste and rising environmental concerns, recycling approaches are being investigated. Since blisters usually contain a balanced amount of plastics and metals, most of the approaches focus on recycling only one material. Therefore, more sustainable recycling approaches which recover both plastic and aluminum fractions are needed. This study investigates the thermal behavior and degradation mechanisms of plastic-rich and aluminum-rich pharmaceutical blisters using various analytical techniques. Structural characterization revealed that plastic-rich blisters have a thicker profile with plastic and aluminum layers, while aluminum-rich blisters consist of plastic layers between aluminum sheets. Thermal degradation analysis showed two main stages for both types: plastic-rich blisters (polyvinyl chloride) exhibited significant weight loss and long-chain hydrocarbon formation between 210 and 285 °C, and aluminum-rich blisters (polyamide/nylon) degraded from 240 to 270 °C. Differential Scanning Calorimetry and Fourier Transform Infrared Spectroscopy analyses confirmed the endothermic behavior of such a transformation. The gas emissions analysis indicated an increased formation of gasses from the thermal treatment of plastic-rich blisters, with the presence of oxygen leading to the formation of carbon dioxide, water, and carbon monoxide. Thermal treatment with 5% O₂ in the carrier gas benefited plastic-rich blister treatment, reducing organic waste by up to 80% and minimizing burning risk, leveraging pyrolytic carbon for protection. This method is unsuitable for aluminum-rich blisters, requiring reduced oxygen or temperature to prevent pyrolytic carbon combustion and aluminum oxidation. Full article

In this work, flexible Cu_2−xS films on nylon membranes are prepared by combining a simple hydrothermal synthesis and vacuum filtration followed by hot pressing. The films consist of Cu₂S and Cu_1.96S two phases with grain sizes from nano to submicron. Doping Se on the S site not only increases the Cu_1.96S content in the Cu_2−xS to increase carrier concentration but also modifies electronic structure, thereby greatly improves the electrical properties of the Cu_2−xS. Specifically, an optimal composite film with a nominal composition of Cu_2−xS_0.98Se_0.02 exhibits a high power factor of ~150.1 μW m⁻¹ K⁻² at 300 K, which increases by ~138% compared to that of the pristine Cu_2−xS film. Meanwhile, the composite film shows outstanding flexibility (~97.2% of the original electrical conductivity is maintained after 1500 bending cycles with a bending radius of 4 mm). A four-leg flexible thermoelectric (TE) generator assembled with the optimal film generates a maximum power of 329.6 nW (corresponding power density of 1.70 W m⁻²) at a temperature difference of 31.1 K. This work provides a simple route to the preparation of high TE performance Cu_2−xS-based films. Full article

Linear polyamides, known as nylons, are a class of synthetic polymers with a wide range of applications due to their outstanding properties, such as chemical and thermal resistance or mechanical strength. These polymers have been used in various fields: from common and domestic applications, such as socks and fishing nets, to industrial gears or water purification membranes. By their durability, flexibility and wear resistance, nylons are now being used in addictive manufacturing technology as a good material choice to produce sophisticated devices with precise and complex geometric shapes. Furthermore, the emergence of triboelectric nanogenerators and the development of biomaterials have highlighted the versatility and utility of these materials. Due to their ability to enhance triboelectric performance and the range of applications, nylons show a potential use as tribo-positive materials. Because of the easy control of their shape, they can be subsequently integrated into nanogenerators. The use of nylons has also extended into the field of biomaterials, where their biocompatibility, mechanical strength and versatility have paved the way for groundbreaking advances in medical devices as dental implants, catheters and non-absorbable surgical sutures. By means of 3D bioprinting, nylons have been used to develop scaffolds, joint implants and drug carriers with tailored properties for various biomedical applications. The present paper aims to collect evidence of these recently specific applications of nylons by reviewing the literature produced in recent decades, with a special focus on the newer technologies in the field of energy harvesting and biomedicine. Full article

Microplastics (plastic particles < 5 mm) are ubiquitous pollutants that have the ability to carry microbiota, including pathogens. Microbial adhesion is usually a sign of pathogenicity; thus, we investigated the adherent microbiota found on 4 mm nylon strips, which were ingested and excreted by wild fish specimens. Retention times were recorded and the polymer analysis of the excreted samples was performed, which showed no signs of degradation, nor did their controls, represented by the nylon strips submerged in the same water tanks. Both the ingested samples and controls presented pathogens in large quantities. Following Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight identification, the dominant genus was represented by Aeromonas, revealing the fact that nylon microplastics can serve as undegradable physical carriers for this pathogen, among others, in the aquatic environment. Full article

Copper-sulfide-based materials have attracted noteworthy attention as thermoelectric materials due to rich elemental reserves, non-toxicity, low thermal conductivity, and adjustable electrical properties. However, research on the flexible thermoelectrics of copper sulfide has not yet been reported. In this work, we developed a facile method to prepare flexible Mn-doped Cu_2−xS films on nylon membranes. First, nano to submicron powders with nominal compositions of Cu_2−xMn_yS (y = 0, 0.01, 0.03, 0.05, 0.07) were synthesized by a hydrothermal method. Then, the powders were vacuum-filtrated on nylon membranes and finally hot-pressed. Phase composition and microstructure analysis revealed that the films contained both Cu₂S and Cu_1.96S, and the size of the grains was ~20–300 nm. By Mn doping, there was an increase in carrier concentration and mobility, and ultimately, the electrical properties of Cu_2−xS were improved. Eventually, the Cu_2−xMn_0.05S film showed a maximum power factor of 113.3 μW m⁻¹ K⁻² and good flexibility at room temperature. Moreover, an assembled four-leg flexible thermoelectric generator produced a maximum power of 249.48 nW (corresponding power density ~1.23 W m⁻²) at a temperature difference of 30.1 K, and had good potential for powering low-power-consumption wearable electronics. Full article

Biofilms in reactors usually grow on impermeable surfaces, and the mass transfer of nutrients in biofilms is mainly driven by diffusion, which is inefficient especially for thick biofilms. In this study, permeable materials (i.e., nylon meshes) were used as biocarriers in a biofilm reactor, and their performance was evaluated and compared with the commercial biocarriers (PE08 and PE10) used for treating slightly polluted water. The results indicate that the mesh-based bioreactor achieved complete nitrification faster than the commercial biocarriers, with a more stable and better effluent quality during long-term operation. At a two-hour hydraulic retention time, the average effluent ammonia (NH₄⁺-N) and nitrite (NO₂⁻-N) concentrations during the stabilized phase were 0.97 ± 0.79 and 0.61 ± 0.32 mg-N, respectively, which are significantly lower than those with commercial carriers. The estimated specific surface area activities for the mesh, PE08, and PE10 carriers were 1620, 769, and 1300 mg-N/(m²·d)), respectively. The biofilms formed on the nylon mesh were porous, while they were compact and nonporous on the PE carriers. Water with substrates might pass through the porous biofilms formed on the meshes, which could enhance mass transfer and result in a better and more stable treatment performance. Full article

(1) Background: There are no high-throughput microtissue platforms for generating bone marrow micro-ossicles. Herein, we describe a method for the assembly of arrays of microtissues from bone marrow stromal cells (BMSC) in vitro and their maturation into bone marrow micro-ossicles in vivo. (2) Methods: Discs with arrays of 50 microwells were used to assemble microtissues from 3 × 10⁵ BMSCs each on a nylon mesh carrier. Microtissues were cultured in chondrogenic induction medium followed by hypertrophic medium in an attempt to drive endochondral ossification, and then they were implanted in NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG) mice, where they were remodeled into bone marrow micro-ossicles. Mice were transplanted with 10⁵ human umbilical cord blood CD34⁺ cells. (3) Results: Micro-ossicles contained more human CD45⁺ cells, but fewer human CD34⁺ progenitor cells than mouse marrow. Human hematopoietic progenitor cells cycle rapidly at non-physiological rates in mouse marrow, and reduced CD34⁺ cell content in micro-ossicles is consistent with the notion that the humanized niche better controls progenitor cell cycling. (4) Conclusions: Assembling microtissues in microwells, linked by a nylon membrane carrier, provides an elegant method to manufacture and handle arrays of microtissues with bone organ-like properties. More generally, this approach and platform could aid bridging the gap between in vitro microtissue manipulation and in vivo microtissue implantation. Full article

A casting technique was used to prepare poly(vinyl alcohol) (PVA) blend polymers with different concentrations of Nylon-6,6 to increase the free-volume size and control the ionic conductivity of the blended polymers. The thermal activation energy for some blends is lower than that of pure polymers, indicating that their thermal stability is somewhere in between that of pure Nylon-6,6 and pure PVA. The degree of crystallinity of the blend sample (25.7%) was lower than that of the pure components (41.0 and 31.6% for pure Nylon-6,6 and PVA, respectively). The dielectric properties of the blended samples were investigated for different frequencies (50 Hz–5 MHz). The σ_ac versus frequency was found to obey Jonscher’s universal power law. The calculated values of the s parameter were increased from 0.53 to 0.783 for 0 and 100 wt.% Nylon-6,6, respectively, and values less than 1 indicate the hopping conduction mechanism. The barrier height (Wm) was found to increase from 0.33 to 0.72 for 0 and 100 wt.% Nylon-6,6, respectively. The ionic conductivity decreases as the concentration of Nylon-6,6 is blended into PVA because increasing the Nylon-6,6 concentration reduces the number of mobile charge carriers. Positron annihilation lifetime (PAL) spectroscopy was used to investigate the free volume’s nanostructure. The hole volume size grows exponentially with the concentration of Nylon-6,6 mixed with PVA. The Nylon-6,6/PVA blends’ free-volume distribution indicates that there is no phase separation in the blended samples. Mixing PVA and Nylon-6,6 resulted in a negative deviation (miscible blends), as evidenced by the interaction parameter’s negative value. The strong correlation between the free-volume size and other macroscopic properties like ionic conductivity suggests that the free-volume size influences these macroscopic properties. Full article

Thanks to the advantages of low disturbance, good concealment and high mobility, bionic fishes have been developed by many countries as equipment for underwater observation and data collection. However, differentiating between true and bionic fishes has become a challenging task. Commonly used acoustic and optical technologies have difficulty in differentiating bionic fishes from real ones due to their high similarity in shape, size, and camouflage ability. To solve this problem, this paper proposes a novel idea for bionic fish recognition based on blue-green light reflection, which is a powerful observation technique for underwater object detection. Blue-green light has good penetration under water and thus can be used as a signal carrier to recognize bionic fishes of different surface materials. Three types of surface materials representing bionic fishes, namely titanium alloy, carbon fiber, and nylon, are investigated in this paper. We collected 1620 groups of blue-green light reflection data of these three kinds of materials and for two real fishes. Following this, three machine learning algorithms were utilized for recognition among them. The recognition accuracy can reach up to about 92.22%, which demonstrates the satisfactory performance of our method. To the best of our knowledge, this is the first work to investigate bionic fish recognition from the perspective of surface material difference using blue-green light reflection. Full article

Despite numerous studies undertaken to define the development and significance of the dynamic membrane (DM) formed on some coarse materials, the optimization of reactor configuration and the control of the membrane fouling of anaerobic dynamic membrane bioreactor (AnDMBR) need to be further investigated. The aim of this study was to design a novel anaerobic gravity-driven dynamic membrane bioreactor (AnGDMBR) for the effective and low-cost treatment of municipal wastewater. An 800 mesh nylon net was determined as the optimal support material based on its less irreversible fouling and higher effluent quality by the dead-end filtration experiments. During the continuous operation period of 44 days, the reactor performance, DM filtration behavior and microbial characteristics were studied and compared with the results of recent studies. AnGDMBR had a higher removal rate of chemical oxygen demand (COD) of 85.45 ± 7.06%. Photometric analysis integrating with three-dimensional excitation–emission matrix fluorescence spectra showed that the DM effectively intercepted organics (46.34 ± 16.50%, 75.24 ± 17.35%, and 66.39 ± 17.66% for COD, polysaccharides, and proteins). The addition of suspended carriers effectively removed the DM layer by mechanical scouring, and the growth rate of transmembrane pressure (TMP) and the decreasing rate of flux were reduced from 18.7 to 4.7 Pa/h and 0.07 to 0.01 L/(m²·h²), respectively. However, a dense and thin morphological structure of the DM layer was still observed in the end of reactor operation and plenty of filamentous microorganisms (i.e., SJA-15 and Anaerolineaceae) and the acidogens (i.e., Aeromonadaceae) predominated in the DM layer, which was also embedded in the membrane pore and led to severe irreversible fouling. In summary, the novel AnGDMBR has a superior performance (higher organic removal and lower fouling rates), which provides useful information on the configuration and operation of AnDMBRs for municipal wastewater treatment. Full article

Pectinolytic enzymes are an important tool for sustainable food production, with a wide range of applications in food processing technologies as well as the extraction of bioactive compounds from pectin-rich raw materials. In the present study, we immobilized commercial pectinase preparation onto pellet and thread shaped nylon 6/6 carriers and assessed its stability and reusability. Five commercial pectinase preparations were tested for different pectin de-polymerizing activities (pectinase, polygalacturonase, and pectin lyase activities). Thereafter, Pectinex^® Ultra Tropical preparation, exhibiting the highest catalytic activities among the studied preparations (p < 0.0001), was immobilized on nylon 6/6 using dimethyl sulfate and glutaraldehyde. The immobilization yield was in accordance with the carrier surface area available for enzyme attachment, and it was 1.25 ± 0.10 U/g on threads, which was over 40 times higher than that on pellets. However, the inactivation of immobilized enzymes was not dependent on the shape of the carrier, indicating that the attachment of the enzymes on the surface of nylon 6/6 carriers was similar. The half-life of enzyme inactivation fast phase at 4 °C was 12.8 days. After 5 weeks, the unused threads retained 63% of their initial activity. Reusability study showed that after 20 successive cycles the remaining activity of the immobilized pectinase was 22%, indicating the good prospects of reusability of the immobilized enzyme preparations for industrial application. Full article

In the skin care field, bacterial nanocellulose (BNC), a versatile polysaccharide produced by non-pathogenic acetic acid bacteria, has received increased attention as a promising candidate to replace synthetic polymers (e.g., nylon, polyethylene, polyacrylamides) commonly used in cosmetics. The applicability of BNC in cosmetics has been mainly investigated as a carrier of active ingredients or as a structuring agent of cosmetic formulations. However, with the sustainability issues that are underway in the highly innovative cosmetic industry and with the growth prospects for the market of bio-based products, a much more prominent role is envisioned for BNC in this field. Thus, this review provides a comprehensive overview of the most recent (last 5 years) and relevant developments and challenges in the research of BNC applied to cosmetic, aiming at inspiring future research to go beyond in the applicability of this exceptional biotechnological material in such a promising area. Full article

Our research has focused on in vitro and in vivo evaluations of a new Carmustine (BCNU)-loaded clinoptilolite-based delivery system. Two clinoptilolite ionic forms—hydrogen form (HCLI) and sodium form (NaCLI)—were prepared, allowing a loading degree of about 5–6 mg BCNU/g of zeolite matrix due to the dual porous feature of clinoptilolite. Clinoptilolite-based delivery systems released 35.23% of the load in 12 h for the BCNU@HCLI system and only 10.82% for the BCNU@NaCLI system. The BCNU@HCLI system was chosen to develop gel and cream semisolid dosage forms. The cream (C_BCNU@HCLI) released 29.6% of the loaded BCNU after 12 h in the Nylon synthetic membrane test and 31.6% in the collagen membrane test, higher by comparison to the gel. The new cream was evaluated in vivo in a chemically induced model of skin cancer in mice. Quantitative immunohistochemistry analysis showed stronger inhibition of B-cell lymphoma-2 (bcl-2) and cyclooxygenase 2 (cox-2) protein expression, known markers for cancer survival and aggressiveness, after the treatment with C_BCNU@HCLI by comparison to all the control treatment types, including an off-label magistral formula commercially available Carmustine cream as reference, bringing evidence that a clinoptilolite-based delivery systems could be used as a cancer drug carriers and controlled release systems (skin-targeted topical delivery systems). Full article

Opportunities for alternatives to synthetic textile dyes are of increasing importance as the world looks to minimize its ecological footprint. Fungal pigments within a unique class of wood-rotting (“spalting”) fungi have been under investigation for several years as a possible solution, and have been shown to be ideally suited as textile dye coatings. Unfortunately, the solvent currently in use for these colorants is dichloromethane (DCM), which is an environmental problem as well as a potential human carcinogen. Recently, researchers found that the pigments from Chlorociboria species, Scytalidium cuboideum, and Scytalidium ganodermophthorum could be carried in some natural oils, which opened up a potential method of delivering pigments onto a host of substrates without utilizing DCM. Although the pigments can be carried in oil, no testing has thus far been conducted as to how oil affects the binding properties of the pigments onto textiles, or how the oil might affect the pigments directly. In this paper, the pigments produced by three well-known wood-rotting fungi were carried in raw linseed oil and applied to cotton, polyester, and nylon. Only the red pigment produced visible color change on the textiles. Cotton and polyester showed the greatest color change when the pigments were dripped onto the fabric, while polyester showed the most color when the textile was submerged into the pigment solution. Unfortunately, the colors faded significantly for all the tests except the saturation test. This indicates that while natural oils may be excellent, nontoxic alternative carriers for DCM, the pigments are not stable within them except at very high concentrations, and therefore natural oils—including raw linseed oil—are not ideal for use in conjunction with these pigments. Full article

In this work, a supercritical carbon dioxide assembly was successfully constructed for dyeing Nylon6 fabric. Primary experiments were carried out to confirm the possibility of bringing the dyeing up to factory scale. A series of disperse azo dyes with potential antibacterial activity were applied to dye the fabric under our study in supercritical carbon dioxide (scCO₂). The factors affecting the dyeing conditions (i.e., dye concentration, time, temperature and pressure) and functional properties were discussed and compared with those in aqueous dyeing. The comparison revealed that elimination of auxiliary chemicals such as salt, carrier or dispersing agent has no diverse effect on dyeing. The color strength of the dyed fabric evaluated by using K/S measurements increased by increasing dye concentration from 2% to 6% owf. (on weight of fabric). The nylon6 fabrics dyed in supercritical carbon dioxide have good fastness properties, and especially light fastness compared with conventional exhaustion dyeing. Antibacterial activity of the dyed samples under supercritical conditions was evaluated and the results showed excellent antibacterial efficiency. Full article