Days Of Soaking Research Articles

Solvent-adaptive hydrogels with lamellar confinement cellular structure for programmable multimodal locomotion

Biological organisms can perform flexible and controllable multimodal motion under external stimuli owing to the hierarchical assembly of anisotropic structures across multiple length scales. However, artificial soft actuators exhibit the limited response speed, deformation programmability and movement capability especially in harsh environments because of insufficient anisotropic hierarchy and precision in structural design. Here, we report a programmed assembly directed confinement polymerization method for the fabrication of environmentally tolerant and fast responsive hydrogels with lamellar assembly-confined cellular structure interpenetrated with highly aligned nanopillars by the directional freezing-assisted polymerization in the predesigned anisotropic laminar scaffold. The obtained hydrogel exhibits ultrafast responsiveness and anisotropic deformation exposed to temperature/light/solvent stimulation, maintaining highly consistent responsive deformation capability in all-polarity solvents over 100 days of soaking. Moreover, the hydrogels implement photoactive programmable multi-gait locomotion whose amplitude and directionality are precisely regulated by the intrinsic structure, including controlled crawling and rotation in water and non-polar solvents, and 3D self-propulsion floating and swimming in polar solvents. Thus, this hydrogel with hierarchically ordered structure and dexterous locomotion may be suitable for flexible intelligent actuators serving in harsh solvent environments.

Hydrothermal synthesis of bioactive calcium silicate glass

This work presents the synthesis of bioactive glass 60SiO2-40CaO (wt.%) by the hydrothermal method without using acid catalysts in shortened synthesis time. The precursors Si(OC2H5)4 (TEOS), Ca(NO3)2.4H2O were introduced in a hydrothermal system, and heated at 150 oC for 24 hours. The resulting gel was dried at 150 oC for 24 hours, then calcined at 800 oC for 3 hours to achieve bioactive glass. Several physical-chemical methods such as TG-DSC, XRD, SEM, and ICP-OES were used to evaluate the synthetic material. The bioactivity and biocompatibility of synthetic glass were evaluated by in vitro experiments in SBF solution and in cell culture environment. The obtained results show that the synthetic glass is an amorphous material, presenting the bioactivity through the formation of a hydroxyapatite mineral layer after 10 days of soaking in SBF solution, and also showing good biocompatibility with cells L-929. Keywords: Bioactive glass, bioactivity, artificial bone, hydroxyapatite, cell viability

In-vitro and thermal stability study of bioglass synthesized from biogenic sources

In this work, the bioactive glasses are derived from biowaste resources such as corn husk ash, sugarcane leaves ashes, and eggshell powder via the melt quench method. The raw materials were melted in a platinum rhodium crucible at 1550 °C, followed by rapid cooling to obtain a glassy phase. In order to assess the in-vitro bioactivity, glasses were soaked in simulated body fluid at 37 °C for different time durations, i.e., 7,14, 21, and 28 days. Biocompatibility of these glasses was also tested on MG-63 cell lines using a 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyl tetrazolium bromide (MTT) assay test. X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) were used to analyze the hydroxyapatite (HAp) layer formation and the thermal stability of soaked samples. SEM micrographs showed the cauliflower and flakes type morphology of hydroxyapatite (HAp) on the glass surfaces after 7 days of soaking in SBF. The EDS analysis also confirmed the formation of a hydroxyapatite layer with a Ca/P ratio that varies from 1.6 to 3.9. MTT assay revealed the biocompatibility for different dosages (1, 2, 5, and 10 mg/ml) of the as-prepared glasses with MG-63 cell lines. The heat treatment of soaked glasses converts the amorphous HAp layer into a crystalline HAp layer, followed by its conversion in stable diopside as main and Ca2.589Mg0.41(PO4)2 as minor phase. The tested glasses exhibited good bioactivity and biocompatibility particularly higher CaO content glass, suggesting for use in bone regeneration applications.

Impact of Ground Granulated Blast Furnace Slag on Calcium Leaching of Low-Heat Portland Cement Paste.

Low-heat Portland cement and ground granulated blast furnace slag are widely used for the preparation of hydraulic concrete. Nevertheless, the effect and mechanism of corrosion on low-heat Portland cement paste mixed with ground granulated blast furnace slag need to be further explored. This paper investigated the impact of ground granulated blast furnace slag on the calcium leaching of low-heat Portland cement paste by evaluating its mass loss, porosity, leaching depth, compressive strength, and Vickers hardness, and comparing it with the leaching performance of ordinary Portland cement paste. Furthermore, the phase composition and morphology of low-heat Portland cement paste containing ground granulated blast furnace slag were analyzed by X-ray diffraction, mercury intrusion porosimetry, and scanning electron microscopy. The results indicate that, after 180 days of soaking in ammonium chloride solution, the mass loss rate, growth rate of porosity, leaching depth, and compressive strength loss rate of low-heat Portland cement paste were 8.0%, 43.6%, 9.1 mm, and 27.7%, respectively, while those of ordinary Portland cement paste were 7.4%, 37.8%, 8.4 mm, and 30.1%, indicating that low-heat Portland cement paste is slightly more damaging than ordinary Portland cement. The addition of ground granulated blast furnace slag could significantly improve the leaching resistance of low-heat Portland cement. For instance, after adding 20% ground granulated blast furnace slag, the above test values were 2.4%, 28.5%, 5.6 mm, and 20.8%, respectively. The reason for this is that ground granulated blast furnace slag has the potential to reduce the porosity of low-heat Portland cement paste, and it can also undergo the secondary hydration reaction with its hydration product Ca(OH)2 to enhance the paste structure. Considering the cost performance, the suitable dosage of low-heat Portland cement paste for satisfactory leaching resistance is about 20%.

Pengaruh Penggunaan Limbah Beton Sebagai (Agregat Halus) Terhadap Uji Kuat Tekan Paving Block

In Indonesia, the use of construction waste is usually not utilized properly most are simply dumped in open fields, and some are used as backfill material. The availability of such materials is vast. The purpose of this research is to determine the compressive strength value of paving blocks that utilize concrete waste with variations in the use of concrete waste, namely: 0%, 10%, 20, 30%, and the value of water absorption in paving blocks that utilize concrete waste with variations in the use of concrete waste, namely: 0%, 10%, 20, 30%. The test results showed that at 28 days of soaking, the compressive strength of normal paving blocks was 16.15 MPa, at 10% substitution of concrete waste for stone ash was 29.17 MPa, at 20% substitution of concrete waste to stone ash amounted to 39.32 MPa, and at 30% substitution of concrete waste to stone ash amounted to 22.66 MPa. From the results of the absorption test, it was found that the absorption value of normal paving blocks was 3.88%, at 10% substitution of concrete waste was 2.30%, at 20% substitution of concrete waste for stone ash was 1.89%, and at 30% substitution of concrete waste for stone ash was 2.80%.

Silver-doped glass-ceramic scaffolds with antibacterial and bioactive properties for bone substitution

The preparation of scaffolds that are both macroporous and mechanically strong is a significant challenge in the development of bioactive ceramic materials for bone substitution. Furthermore, the introduction of beneficial extra-functionalities such as bacterial inhibition is highly appealing but adds complexity to implant design and production. In this study, we aimed to fabricate highly porous, bioactive and antibacterial glass-ceramic scaffolds with interconnected macropores through the foam replica method. The scaffolds were sintered at two different temperatures (620 and 850 °C), yielding glassy or partially crystallized materials, respectively. The scaffold produced at higher temperature was found to be highly porous (>75 vol%), mechanically stronger and able to induce hydroxyapatite formation after three days of soaking in SBF (in vitro bioactivity). In order to confer antibacterial activity, silver (Ag) ions were introduced onto the scaffold surface through ion exchange in an aqueous solution. Compositional analysis confirmed the successful doping of the scaffold surface with silver, which was continuously released in SBF for at least 28 days, as revealed by ICP-MS. Finally, the antibacterial action of the Ag-doped scaffold was confirmed towards Staphylococcus epidermidis. Overall, the results reported in this work show the potential of foam-like Ag-doped bioactive glass-ceramic scaffolds to be used in applications requiring bone substitution and antibacterial properties.

The Effect of Different Priming Applications on The Germination of Seeds of Some Hazelnut Cultivars

In this study, the germination of pericarp and non-pericarp-free seeds of the Kara and Tombul cultivars was examined in relation to the effects of hormonal and hydro-priming treatments. According to the results, the control group produced the best pericarp seed of the Kara variety in terms of germination rate, root length, root fresh-dry weight, plant fresh-dry weight, and number of leaves. The seeds of the Kara variety without pericarp, 60 minutes of Perlan + 2 days of soaking in water in the control group (56 seeds), and the pericarpless seeds of the Kara variety, respectively, and the seeds with pericarp of the best Tombul variety (53.6 units), produced the best results when the root diameters were measured. The application of 30 minutes of Perlan plus two days of soaking in water to the seeds without pericarp of the Kara cultivar produced the best results in terms of leaf area, and the control group produced the best results for the amount of chlorophyll in the seeds without pericarp of the Tombul and Kara cultivars.

Pore fluid salinity effects on post-stabilization performance of cement-treated Marl

Soil improvement using chemical admixtures has been extensively investigated in the recent past and these admixtures are abundantly being used on various construction projects. However, there is a need to elucidate the long-term performance of stabilized geomaterials under aggressive pore fluid environments such as high salinity of groundwater in coastal areas. This study presents the effects of the concentration of pore fluid salinity on the post-stabilization behavior of cement-treated Marl specimens to brine solution from Sabkha deposits and rejected water from a water treatment plant. Unconfined compressive strength (UCS), mineralogy, chemical, and microstructural evaluations have been carried out in this regard. minerals like albite and muscovite completely leached out of the samples after 28 days of soaking in a saline environment. A new mineral Attapulgite was formed at various concentration levels of the pore fluid. Significant changes in the chemical composition were also observed in various phases of the experiments. Moreover, at all salinity levels, the UCS initially increased to a maximum of 75 % which later reduced to a value less than the original strength whereas the elastic modulus (E50) increased as the soaking period progressed. Lastly, it is emphasized that the engineering properties of treated soils exposed to aggressive pore fluids should be carefully assessed for a reliable prediction of the long-term performance of geotechnical structures.

Utilization of waste face masks to reinforce magnesite mine tailings for sustainable subgrade construction

The disposal of magnesite mine tailings (MMT), a by-product of magnesite mining, raises significant environmental concerns due to its adverse effects on soil, water and air quality. Likewise, the improper disposal of used face masks exacerbates environmental burdens. The innovative use of polypropylene fibres (PPF) derived from disposable face masks to reinforce. This study explores the compaction and strength characteristics of PPF-MMT composites with varying fibre content to develop a sustainable composite for subgrade construction. The findings indicate that the addition of PPF increases optimal moisture content and decreases maximum dry density. Shear strength analysis reveals a linear failure envelope for both MMT and PPF-MMT, with initial angle of internal friction improvement at lower PPF content (0.25% and 0.5%) but a decline at higher contents (0.75% and 1%). Importantly, PPF-MMT consistently exhibits a unique strain-hardening behaviour across all stress levels, distinguishing it from MMT, which only transitions to strain-hardening at higher stresses. Under vertical load, MMT shows contraction, while the PPF-MMT composite initially contracts but later dilates due to increased fibre-MMT interaction during horizontal displacement. Furthermore, California bearing ratio (CBR) tests demonstrate increased dry CBR with PPF, reaching a peak of 33.85% at 0.5% fibre content. The soaked CBR tests affirm the remarkable durability of PPF-MMT, maintaining significantly higher values than MMT even after 60 days of soaking. The study concludes that 0.5% fibre content as optimum dosage.

Fabrication and characterization of 3D-printed composite scaffolds of coral-derived hydroxyapatite nanoparticles/polycaprolactone/gelatin carrying doxorubicin for bone tissue engineering

In this study, nanocomposite scaffolds of hydroxyapatite (HA)/polycaprolactone (PCL)/gelatin (Gel) with varying amounts of HA (42–52 wt. %), PCL (42–52 wt. %), and Gel (6 wt. %) were 3D printed. Subsequently, a scaffold with optimal mechanical properties was utilized as a carrier for doxorubicin (DOX) in the treatment of bone cancer. For this purpose, HA nanoparticles were first synthesized by the hydrothermal conversion of Acropora coral and characterized by using different techniques. Also, a compression test was performed to investigate the mechanical properties of the fabricated scaffolds. The mineralization of the optimal scaffold was determined by immersing it in simulated body fluid (SBF) solution for 28 days, and the biocompatibility was investigated by seeding MG-63 osteoblast-like cells on it after 1–7 days. The obtained results showed that the average size of the synthesized HA particles was about 80 nm. The compressive modulus and strength of the scaffold with 47 wt. % HA was reported to be 0.29 GPa and 9.9 MPa, respectively, which was in the range of trabecular bones. In addition, the scaffold surface was entirely coated with an apatite layer after 28 days of soaking in SBF. Also, the efficiency and loading percentage of DOX were obtained as 30.8 and 1.6%, respectively. The drug release behavior was stable for 14 days. Cytotoxicity and adhesion evaluations showed that the fabricated scaffold had no negative effects on the viability of MG-63 cells and led to their proliferation during the investigated period. From these results, it can be concluded that the HA/PCL/Gel scaffold prepared in this study, in addition to its drug release capability, has good bioactivity, mechanical properties, and biocompatibility, and can be considered a suitable option for bone tumor treatment.Graphical

Hydroxycarbonate apatite formation, cytotoxicity, and antibacterial properties of rubidium-doped mesoporous bioactive glass nanoparticles

Rubidium (Rb) has been shown to impact biological activity. This work synthesized Rb-doped mesoporous bioactive glass nanoparticles (MBGNs) based on the composition 70SiO2–30CaO mol% with a sol-gel method. Rb2O was substituted for CaO in concentrations of 5 and 10 mol%. The influence of Rb incorporation on the hydroxycarbonate apatite (HCA) formation, cytotoxicity, and antibacterial capacity of particles was evaluated. XRD analysis confirmed the amorphous structure of the particles. In vitro, biomineralization studies showed HCA on the surface of MBGN and Rb-doped MBGN pellets after 7 days of soaking in simulated body fluid (SBF). An inhibition zone of Escherichia coli (E.coli) and Staphylococcus aureus (S. aureus) around Rb-doped MBGN pellets was detected, while MBGN pellets did not show any inhibition zone. Additionally, MC3T3-E1 pre-osteoblastic cells demonstrated cytocompatibility when exposed to Rb-MBG suspensions at different concentrations of up to 250 µg/ml. Based on their overall properties, Rb-containing MBGNs are proposed for biomedical applications, such as filler nanoparticles in composite bone scaffolds.

Applying the Alkali-Activation Method to Encapsulate Silicon Nitride Particles in a Bioactive Matrix for Augmented Strength and Bioactivity.

The development of bioactive ceramics still poses challenges in finding a good compromise between bioactivity and mechanical robustness. Moreover, a facile, low-cost and energy-saving synthesis technique is still needed. This study concerns the synthesis of a bioactive material by growing a bioactive Na-Ca-Mg-Si-based ceramic matrix produced using the alkali-activation method on silicon nitride (Si3N4) particles. This technique simultaneously forms the matrix precursor and functionalizes the Si3N4 particles' surface. The optimal strength-bioactivity compromise was found for the composition containing 60 wt.% Si3N4 and 40 wt.% of the matrix exhibiting good compressive strength of up to 110 MPa and extensive precipitation of hydroxyapatite on the sample surface after 7 days of soaking in simulated body fluid. This innovative approach merging strong non-oxide binary ceramics with the versatile and low-cost alkali-activation method holds great expectations for the future in biomaterials.

The effect of varying levels of potassium hydroxide-treated false Yam seed meal on growth performance, haematology and serum biochemistry of male broiler chickens

This study was carried out to evaluate sequential treatment of false yam seeds as substitute for maize in broiler chicken diets on their growth, carcass, haematology and serum biochemistry. Ripped fruits of false yam plants growing in the wild were harvested by hand picking. The fruits were partially sun-dried to reduce their moisture content and facilitate cracking to obtain the false yam seeds (FYS). The fresh FYS were crushed with a stone to reduce size, increase surface area and facilitate processing. The freshly crushed false yam seeds were subjected to multiple-stage processing where seeds were first soaked in ordinary water (i.e., addition of fresh seeds in ordinary water at a ratio of 1:2, wt/vol) for 12 days with water being changed every 3 days. After the 12 days of soaking, the seed sample was washed with clean ordinary water. In the second stage of processing, soaked FYS was soaked in a solution of 1M concentration of potassium hydroxide at a ratio of 1:2 (wt/vol) for 24 hours, after which the sample was washed thoroughly with clean ordinary water. The last stage of processing involved blanching of potassium hydroxide-treated seeds, firstly by immersing the sample in hot water (900C) for 20 minutes and then transferring it into cold water (40C) for 40 minutes. The treated seed sample was then washed with clean water, sun-dried to approximately 12% moisture on a cement floor and ground into gritty flour using a hammer mill. The treated false yam seed meal was labeled as KOH_T FYSM. At 21 d of age, 128 birds were individually weighed and then randomly assigned to one of four dietary treatments in quadruplicate lots. Each replicate had 8 male broilers. The mean live-weight of birds in each replicate was 883 g (±0.05). The four treatments included the control without KOH_T FYSM; treatments 2, 3 and 4 contained 100, 300 and 500g/kg KOH_T FYSM respectively replacing maize (wt. /wt. basis) in a completely randomized design. The birds were fed various diets for 35 d. The growth response of male broiler chickens fed diets supplemented with varying levels of KOH_T FYSM revealed no significant (P<0.05) difference in all growth parameters measured. Carcass dress weight and carcass dressing showed no significant (P>0.05) difference at 500g/kg. However, the relative weight of organs revealed a significant (P<0.041) increase in the heart weight and a reduction in the weights of the liver and the spleen. Haematological parameters evaluated revealed a significant (P<0.05) decrease in the haemoglobin, mean corpuscular volume, mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration as KOH_T FYSM was increased in the diets. The economics of replacing maize with KOH_T FYSM in the diets of male broilers revealed that price per kg of feed reduces as the test material was increased in the diets. Inclusion of KOH_T FYSM up to 500g/kg in the diets of male broilers had no adverse effect on their growth performance. However, its inclusion influenced internal organ weights such as the liver, spleen and heart. Economics of feeding KOH_T to broilers did not increase cost of feeding, suggesting that, There is an economic value for using this product for broiler chickens as an alternative to maize during periods of scarcity and can be recommended for use by farmers where this plant is available.

Time-shift effect of spontaneous combustion characteristics and microstructure difference of dry-soaked coal

The physical and chemical properties of the air-dried residual coal after soaking in the goaf will change, resulting in an increase in its spontaneous combustion tendency. This study aimed to look into the features and mechanism of soaked-dried coal's spontaneous combustion. Five samples of coal were dried to various degrees, and the weight loss features during thermal processing were examined. Based on this, the pore structure and chemical structure characteristics of the coal samples with the highest tendency to spontaneous combustion were quantitatively examined, and the mechanism by which soaking-drying affected the spontaneous combustion heating process of the remaining coal in goaf was investigated in turn. The results show that T1 decreases with the increase of drying time, T2–T6 shows a fluctuating change, and the ignition activation energy of 36-S-Coal is smaller than that of other coal samples. The pore type of 36-S-Coal changes from a one-end closed impermeable pore to an open pore, and the pore group area is large. During the 36 h drying process, the internal channels of the coal were dredged, and a large number of gravels and minerals were precipitated from the pores with the air flow. A large number of gravels were around the pores to form a surface structure that was easy to adsorb various gases. Furthermore, infrared spectroscopy was used to analyze the two coal samples. It was found that soaking and drying did not change the functional group types of coal samples, but the fatty chain degree of 36-S-Coal was reduced to 1.56. It shows that the aliphatic chain structure of coal is changed after 36 h of drying after 30 days of soaking, which leads to the continuous shedding of aliphatic chain branches of residual coal, and the skeleton of coal is looser, which makes the low-temperature oxidation reaction of 36-S-Coal easier. Based on the above results, the coal-oxygen composite mechanism of water-immersed-dried coal is obtained, and it is considered that the key to the spontaneous combustion oxidation process of coal is to provide oxygen atoms and accelerate the formation of peroxides.

Sludge composting with self-produced carbon source by phosphate buffer coupled hyperthermophilic pretreatment realizing nitrogen retention

During sludge composting, ammonia emissions is the main pathway of nitrogen loss. In addition to regulating pH, increasing the carbon source is also important for controlling ammonia emissions. Previous studies have focused on additional carbon sources, while this study used phosphate-buffered saline (PBS) and hyperthermophilic pretreatment (HP) to release difficult-to-utilize carbon sources in extracellular polymeric substance (EPS) for composting. The PBS concentration was 0.22 mmol/g total matter (TM), PBS soaking days were 4.74, HP temperature was 149.46 °C, and the soluble chemical oxygen demand (SCOD) was 45.08 g/kg. Compared with the control check, the peak ammonia emission concentration in the pretreated group was reduced by 8.70 % and the total nitrogen loss was reduced by 18.10 %. Changes in EPS, ammonia assimilation activity, and microbial community composition demonstrated that PBS and HP released the carbon source from the sludge, promoted ammonia assimilation, and enriched bacteria related to ammonia assimilation such as Bacillus (16.52 %). HP treatment made Acinetobacter (12.5 %) the dominant genus in the calefactive phase, and the enrichment of Actinobacteriota (27.27 %) promoted the composting maturity. However, total pretreatment reduced the porosity and permeability of the sludge and affected the activity of microorganisms. Considering the cost of energy consumption, partial pretreatment has more practical application prospects.

A maceration technique for soft plant tissue without hazardous chemicals.

Current methods for maceration of plant tissue use hazardous chemicals. The new method described here improves the safety of dissection and maceration of soft plant tissues for microscopic imaging by using the harmless enzyme pectinase. Leaf material from a variety of land plants was obtained from living plants and dried herbarium specimens. Concentrations of aqueous pectinase and soaking schedules were optimized, and tissues were manually dissected while submerged in fresh solution following a soaking period. Most leaves required 2-4 h of soaking; however, delicate leaves could be macerated after 30 min while tougher leaves required 12 h to 3 days of soaking. Staining techniques can also be used with this method, and permanent or semi-permanent slides can be prepared. The epidermis, vascular tissue, and individual cells were imaged at magnifications of 10× to 400×. Only basic safety precautions were needed. This pectinase method is a cost-effective and safe way to obtain images of epidermal peels, separated tissues, or isolated cells from a wide range of plant taxa.

Tuning of Silver Content on the Antibacterial and Biological Properties of Poly(ɛ-caprolactone)/Biphasic Calcium Phosphate 3D-Scaffolds for Bone Tissue Engineering.

There is a growing interest in tissue engineering, in which biomaterials play a pivotal role in promoting bone regeneration. Furthermore, smart functionalization can provide biomaterials with the additional role of preventing orthopedic infections. Due to the growing microbial resistance to antimicrobials used to treat those infections, metal ions, such as silver, thanks to their known wide range of bactericidal properties, are believed to be promising additives in developing antibacterial biomaterials. In this work, novel poly(ε-caprolactone) (PCL)-based 3D scaffolds have been designed and developed, where the polymer matrix was modified with both silver (Ag), to supply antibacterial behavior, and calcium phosphates (biphasic calcium phosphate, BCP) particles to impart bioactive/bioresorbable properties. The microstructural analysis showed that constructs were characterized by square-shaped macropores, in line with the morphology and size of the templating salts used as pore formers. Degradation tests demonstrated the important role of calcium phosphates in improving PCL hydrophilicity, leading to a higher degradation degree for BCP/PCL composites compared to the neat polymer after 18 days of soaking. The appearance of an inhibition halo around the silver-functionalized PCL scaffolds for assayed microorganisms and a significant (p < 0.05) decrease in both adherent and planktonic bacteria demonstrate the Ag+ release from the 3D constructs. Furthermore, the PCL scaffolds enriched with the lowest silver percentages did not hamper the viability and proliferation of Saos-2 cells. A synergic combination of antimicrobial, osteoproliferative and biodegradable features provided to 3D scaffolds the required potential for bone tissue engineering, beside anti-microbial properties for reduction in prosthetic joints infections.

Training of spicy salted eggs making in Tanjung Kesuma Village, Purbolinggo Subdistrict, East Lampung Regency

Tanjung Kesuma Village is one of the cultivation centers of egg-laying hens. The product generated from this cultivation is chicken eggs. Eggs contain complete nutrients, such as carbohydrates, fats, proteins, minerals, and vitamins. However, eggs exhibit a drawback, which makes them cannot be stored for a long time. Salted eggs are one form of processing to increase the shelf life of eggs without reducing their nutritional content. The purpose of this community services activity was to conduct training in making salted eggs. The implementation of this activity was expected to increase the selling value of eggs and their shelf life. Eggs that have been processed into salted eggs have an increased selling value and a longer shelf life. The methods used in this activity were socialization and extension, training, and practice of making salted egg. This activity was conducted on 3 January 2023. The practice of making spicy salted eggs used the basic ingredients, consisting of chicken eggs, salt, and condiments (garlic, red pepper, and lemongrass) with 10–14 days of soaking. The results of the training have generated a good responses from the Family Welfare Program (PKK) housewives participants, in the form of quite interesting discussions, and all participants were involved in the practice of making spicy salted eggs. This community services activity is expected to help participants to better understand the innovation of making salted eggs using the brine and condiments marinade method.

A sustainable body-temperature self-healing polyurethane nanocomposite coating with excellent strength and toughness through optimal hydrogen-bonding interactions

Obtaining sustainable low-temperature self-repairing polyurethane (PU) materials with outstanding mechanical performance is difficult and of pivotal importance to the corrosion protection of metals. Herein, we utilize the bio-based 2,5-Tetrahydrofurandimethanol (THFDM) chain extender and eco-friendly polydopamine-modified hydroxyapatite (PDA@HAp) nanosheets to fabricate sustainable body-temperature PU nanocomposite. The nanocomposite has an ultra-high tensile strength (36.84 MPa), outstanding toughness (211.8 MJ m−3), and good self-healing ability (81.97 %, 35 °C for 24 h; 94.46 %, 80 °C for 15 min) thanks to own optimal hydrogen-bonding interactions. What's more, the composite coating after 30 days of soaking in 3.5 wt% NaCl solution also exhibits an impedance value (Zf=0.01 Hz) of 2.80 × 108 Ω cm2 profiting from the barrier capability of PDA@HAp nanosheets. Hence, this work presents an effective way in which researchers can create a sustainable self-repairing PU nanocomposite with outstanding mechanical performance and corrosion resistance.

Cu/Ti co-doping boosting P2-type Fe/Mn-based layered oxide cathodes for high-performance sodium storage

Environmentally friendly P2-type layered iron manganese oxides appear to be one of the most potential cathode materials for sodium-ion batteries (SIBs). However, their practical application is hindered by the unfavorable phase transitions, dissolution of transition metals, and poor air stability. One effective strategy by either single-cation doping or high-cost Li involved co-doping is used to alleviate the problems. Here, low-cost Cu/Ti co-doping is introduced to boost P2-Na0.7Cu0.2Fe0.2Mn0.5Ti0.1O2 as an air and electrochemical stable cathode material for SIBs. The resulting electrode delivers an initial capacity of 130 mAh g−1 at 0.1C within 2.0–4.2 V, a reversible discharge capacity of 61.0 mAh g−1 at a high rate of 5C and a capacity retention ratio exceeding 71.1% after 300 cycles. In particular, the co-doped crystal structure is well-maintained after 1 month of exposure to air, and even 3 days of soaking in water. Furthermore, the enhancement is elucidated by the effectively mitigated P2–Z and the completely suppressed P2–P′2 phase transitions, the decreased volume variation proved by in-situ X-ray diffraction (XRD), as well as the lowered transition-metal dissolution evidenced by inductively coupled plasma optical emission spectrometer (ICP-OES) and X-ray photoelectron spectroscopy (XPS). The low-lost Cu/Ti doping strategy could thus be effective for designing and preparing environmentally friendly and high-performance cathode materials for SIBs.