Dense Texture Research Articles

Investigating the physical characteristics and antibacterial properties of the cork back from Quercus variabilis

This study presents for the first time results on structure feature, basic physical properties, torrefaction treatment, adsorption property, component content and antimicrobial properties of the cork back from Quercus variabilis. The cork back consisted of numerous white stone cell bundles with a dense and firm texture and irregularly shaped cells exhibiting considerable deformation and wrinkles. The cork back had the average density of 0.37 g/cm3, average hardness of 91.60 HA and the average thickness was 31.44 % of the total cork thickness. The average colorimetric parameters values of L*, a*, and b* of the cork back were 21.92, 2.34, and 6.42, respectively. Increasing torrefaction temperature increased the quality loss of the cork back, decreased energy yield and volatile matter content, and increased ash and fixed carbon content. With the elevation of fixed carbon, the higher calorific value of the cork back also increased. Following high-temperature torrefaction at 300 °C, the higher calorific value of cork back was 24.00 MJ/kg which increased by 30.29 % compared to untreated cork back. The cork back powder had significant adsorption performance for methylene blue and the maximum adsorption capacity could reach 511.61 mg/g. Compared with cork，the cork back had a high content of lignin and polysaccharides, with a suberin content of only 4.07 %. The total extractives content in cork back was 7.49 %. The water extractives of the cork back exhibited the most significant inhibitory effect on Escherichia coli, with the lowest inhibitory concentration recorded at 2 mg/mL. This research offers essential data for the processing and utilization of the cork back, which contributes to enhance the utilizing efficiency of cork resources.

Composting as a Cleaner Production Strategy for the Soil Resource of Potato Crops in Choconta, Colombia

Choconta is the municipality in Colombia with the greatest prevalence of potato planting, representing 70.90% of the total territory. However, this crop has been affected by the presence of pests, diseases, and chemical contaminants from pesticides and chemical fertilizers that deteriorate the soil and, therefore, the quality of the final product. Compost (organic waste with specific characteristics and made from waste generated in Choconta) was studied as a sustainable production strategy to increase soil quality and thereby the quality of the local potato crop. For this purpose, a 3 × 2 experiment design was implemented with three treatments (0%, 25%, and 50% compost) and two variables (young potato and mature potato) in duplicate for 4 months. In this experiment, the use of compost led to an improved final product, which went from a floury texture to a dense and creamy texture. The use of compost also reduced the levels of heavy metals, such as lead, with a higher removal in treatment 3 (50% composting). The estimated direct cost of the composting process was USD 280.85, slightly lower than that of the application of fertilizers at USD 294.48. The use of fertilizers has a higher environmental impact due to the use of chemical products that have environmental and health implications. Using compost did not influence tuber harvest time but had a positive impact on tuber texture quality and on soil resources through the reduction in heavy metals, especially lead (16.40–18.03 ppm for treatment 1, 17.96–18.49 ppm for treatment 2, and 15.67–17.88 ppm for treatment 3). Using compost could be environmentally and economically beneficial for local farmers, and it promotes the circular economy and sustainable communities.

Research on rapid prediction method of laser cladding deposited layer state based on molten pool texture sequence

A texture sequence feature combining texture statistical characteristics with time series is proposed for rapid prediction of the state of laser cladding deposited layer. Texture features in the molten pool images are extracted using high-order dense texture descriptor operators and transformed into probability sequences with the aid of multi-cell histograms. Texture features are screened based on the types of points of interest to improve the sequence, enhancing the prediction accuracy and speed for deposited layer. For different types of points of interest, the optimal texture sequence obtained achieves an improvement of more than 6% in prediction accuracy for deposited layer state compared to the full-texture sequence. The proposed texture sequence features, when compared with molten pool image features, exhibit an average improvement in prediction speed of more than 17 times across different deep learning models. Overall, the results indicate that this method significantly improves prediction speed while maintaining accuracy, satisfying the requirements of high-speed monitoring in laser cladding.

Reformulation of gambang bread with additional pectin and coconut dregs powder as wheat flour and breadcrumb substitute

Gambang bread is a traditional no-yeast Indonesian bread characterized by its palm sugarlike brown colour, dense texture, and spice taste. Coconut dregs are high in dietary fiber but easy to spoil, so blanching is an effective way to prolong the coconut dregs' shelf life. This study investigated the effects of the blanching method and time on yield, water content, fat content, and dietary fiber content of coconut dregs powder. Moreover, the effects of coconut dregs powder substitution ratio and pectin concentration on the microstructure and physical characteristics of the bread (expansion volume and hardness) were studied. Hot water blanching produced coconut dregs powder with lower yield and fat content, as well as higher moisture and dietary fiber content than steam-blanched coconut dregs powder. Blanching time only affected dietary fiber content. 10 mins of blanching produced coconut dregs powder with higher dietary fiber content than 5 mins of blanching. Hot water blanching treatment for 10 mins was chosen as the best treatment. This treatment produced 43.12±0.64% coconut dregs powder. Moreover, the chemical characteristics of chosen coconut dregs powder were 5.40±0.01% water, 34.10±1.56% fat, 3.73±0.1% protein, 0.45±0.02% ash, 55.53±1.28% carbohydrate, and 73.90±0.02% dietary fiber. Higher substitution of coconut dregs powder increased hardness and decreased the expansion volume of gambang bread. Meanwhile, adding pectin significantly reduced the hardness of gambang bread. The best gambang bread was obtained from 10% substitution coconut dregs powder and 0.5% additional pectin. Bread microstructure showed that substituting coconut dregs disrupted the continuity gluten matrix more than control bread.

The Effect Of Jicama Flour Subtitution On The Quality Of Cat’s Tongue Cookies

This research is motivated by Cookies are small foods with a dense and crunchy texture that are made by baking or in the oven and last more than one month (Rahma Wati, 2013:26). There are various types of cookies in Indonesia, one of which is cat’s tongue cookies. Cat tongue cookies come from the Netherlands, in dutch these cookies are usually called “KATTE TONG”. Therefore, in this research the author used jicama flour as a partial substitute for wheat flour in making cat’s tongue cookies. This research aims to analyze the effect of 15%, 30%, 45% substitution of jicama flour on the quality of the shape, color, aroma, texture, and taste of the cat’s tongue cookies produced. This type of research is a pure ecperiment (true experiment) with a completely randomized design method with one factor. The type of data is primary data sourced from 3 expert panelists who filled in the organoleptic test format. The data obtained was tabulated in table form and analysis of variance (ANOVA) was carried out, if it was significantly different, it was continued with the Duncan test.

Highly-crystalline Vanadium Dioxide by Hydrothermal for Infrared Detectors

Abstract Infrared detectors are utilized across a diverse range of applications, yet they currently face challenges such as high power consumption and sensitivity to environmental. Vanadium dioxide, a popular material for infrared detectors, boasts a superior temperature coefficient of resistance and rapid response speed. However, it suffers from a substantial thermal hysteresis width. To overcome this limitation, the film structure is meticulously designed to exhibit a uniform, dense texture with a high degree of orientation and crystallinity on a sapphire substrate. This enhancement significantly boosts the infrared responsiveness of the detector. Under optimal conditions, specifically a bias voltage of 50 mV and infrared irradiation of 150 mW, the photocurrent can achieve a remarkable value of 5.55 μA, while the response speed reaches an impressive 0.23 μA/s. These improvements hold promising implications for infrared detection technology, particularly in areas such as night vision and electrical maintenance.

Comparative Analysis of Structural and Functional Properties of Dietary Fiber from Four Grape Varieties.

Muscadine grapes are characterized by their large and abundant seeds and hard and thick skins that contain significant amounts of dietary fiber (DF). The current study investigated the chemical constituents, molecular architecture, and physicochemical attributes of DF derived from Muscadine grapes (Granny Val and Alachua) and compared them with those derived from Shine Muscat and Kyoho. Using a combined enzymatic method, the total dietary fiber (TDF) was extracted and divided into two parts: soluble dietary fiber (SDF) and insoluble dietary fiber (IDF). TDF (mainly IDF, with a small fraction of SDF) was dominated by cellulose, followed by pectin and hemicellulose. In addition, Granny Val and Alachua had a significantly higher abundance of TDF and IDF compared with Shine Muscat and Kyoho. Moreover, Shine Muscat had significantly the highest abundance of SDF among the four grape varieties. Of note, IDF from Granny Val and Alachua exhibited a complex and dense texture on its surface, and notably outperformed Shine Muscat and Kyoho in terms of cholesterol, fatty acid, heavy metal adsorption, and antioxidant activity. Collectively, Muscadine grapes, i.e., Granny Val and Alachua in the current study, possessed elevated DF levels (predominantly IDF), and their enhanced bioactivity underscored their potential as a potential food ingredient for further use.

Structural, micro-structure, magnetic and dynamic magneto-elastic properties of samarium-doped nickel-zinc spinel ferrites for efficient power conversion applications

Development of high-quality ferrites behaved enhanced properties via inclusion of ions in 3dn and 4fn series are desirable for efficient power conversion solid-state devices. Nevertheless, inadequate microscopic behaviors with complex chemistry in materials enables researchers to design and produce the macroscopic target device that remained rudimentary and mindless. In this work, the microscopic properties in nickel-zinc spinel ferrite series of Ni0.8Zn0.2SmxFe2-xO4 (x = 0, 0.02, 0.04, 0.06, 0.08) encompassing XRD, SEM, EDS, VSM, FTIR and ESR were systemically characterized, and the evolutionary mechanism of the corresponding structural, micro-structure, elemental composition and distribution, magnetic, cations exchange, and micro-magnetic behavior was profoundly revealed. Under microscopic examinations, the optimum composition at x = 0.02 with well-arranged spinel structure, dense texture with expected elemental composition, favorable soft magnetic properties and micro-magnetic behaviors is evident. Fortunately, this optimum is in coincidence with the achievable maximum magneto-mechanical coefficient, even the macroscopic electric properties with stronger magnetoelectric (ME) interactions and higher power conversion efficiency (PE) in tri-layered ME samples as expected. Experimental results show that the eventual PE reaches its maximum of 75.67 % under Ropt = 33kΩ for samples at x = 0.02, and exhibit a 2.24 times higher PE than that of sample without samarium substitution. These findings provide a holographic perspective to connect the microscopic beneficial effects of materials to bulk device that are promising for efficient power conversion solid-state electronics.

Pasta Drying Defects as a Novel Ingredient for Hard Dough Biscuits: Effect of Drying Temperature and Granulation on Its Functionality.

Various drying temperatures impact the texture of pasta and cause different drying defects. These by-products could reflect techno-functional characteristics which are suitable for cereal products. This research addresses the influence of low (LT) and high (HT) drying pasta defects with two granulations on the theoretical and functional characteristics of hard dough biscuits. By shifting from a LT to HT drying temperature, a higher onset and peak temperature was found due to the higher mobility of starch molecules with increasing crystalline stability. The lowest transition enthalpy of biscuit formulation was also observed for higher incorporation of fine HT pasta regrinds. The algebraic model of dough with consistography determined the poor-extensible gluten and a high resistance with a greater value of P/L and P indices for LT regrinds. Scanning electron microscopy revealed a heavy and dense texture with immersed starch granules for additional fine regrinds while coarse samples caused swell granules with greater diameter. Moreover, fine HT regrinds reflected the lowest L* value for biscuit due to heat gradient tension with the hard milling process which leads to protein denaturation with decreasing nitrogenous.

Organoleptic Testing Of The Use Of Purple Sweet Potato Flour On The Quality Of Cookies

Cookies are dry cakes made from soft dough with a high fat content that are relatively crispy when broken and the cross-section of the pieces has a dense texture, made from a mixture of wheat flour, refined sugar, margarine, meizena flour and powdered milk. Purple sweet potatoes are more focused on developing flour and starch because the color of the flour produced is more like purple sweet potato flour, and purple sweet potatoes tend to be more fragrant and have a distinctive taste of purple sweet potatoes. So purple sweet potato flour can be used in making cookies. This research aims to analyze the effect of using 15%, 40% and 45% purple sweet potato flour on the quality of the shape, color, aroma, texture and taste of the cookies produced. This type of research is a pure experiment using a Completely Randomized Design method. The data used is primary data obtained directly from 3 expert panelists by filling in the organoleptic test format for the quality of cookies with the effect of using purple sweet potato flour. The data obtained was then tabulated in table form and Analysis of Variance (ANOVA) was carried out, if Fh>Ft then continued with the Duncan Test. The results of the research showed that there was a significant effect of using 15%, 40%, and 45% purple sweet potato flour on the quality of color (purple), aroma (fragrant purple sweet potato), and sweetness (sweet taste and distinctive taste of sweet potato). The best results from the cookie quality test using purple sweet potato flour were 45%.

Site Selection of Medical Waste Disposal Facilities Using the Interval-Valued Neutrosophic Fuzzy EDAS Method: The Case Study of Istanbul

In recent years, as a result of the increasing demand for health services, medical waste (MW) generated from health facilities has increased significantly. Problems that threaten the environment and public health may arise as a result of inadequate medical waste management (MWM), especially in densely populated metropolitan areas. Therefore, it is very important that the disposal process of waste is carried out in a way that minimizes harm to human health and the environment. MW disposal site selection is among the most important decisions that local governments make. These decisions have many conflicting and similar criteria and alternatives. However, decision-makers may experience significant uncertainty when evaluating the alternatives. This study adopts the interval-valued neutrosophic (IVN) fuzzy EDAS method for the evaluation of MW disposal facility siting alternatives in Istanbul. This approach is used to evaluate potential sites based on a comprehensive, hierarchical criteria framework designed to address data uncertainty and inconsistency common in multi-criteria decision-making (MCDM) scenarios. Within the scope of the study, six main criteria (distance settlement area, social acceptance, costs, environmental impacts, infrastructure facilities, and disaster and emergency) and nineteen sub-criteria are meticulously analyzed. Considering the geographical location and dense urban texture of Istanbul, the study emphasizes the criteria related to distance to residential areas, logistics costs, and potential disaster risks. Among the identified criteria, land costs, topographical features, proximity to landfills, and distance to high-voltage lines are emphasized as the least important criteria. This study, which evaluated various alternatives, identified Pendik, located on the Anatolian side of Istanbul, as the most suitable site for MW disposal due to its minimal risk. The study also compares the four main alternatives and highlights their relative strengths and weaknesses.

Effect of protease hydrolysis pretreatment on extruder response and the structural characteristics of high-moisture plant-protein extrudates

This study aimed to investigate the effect of protease hydrolysis pretreatment (PHP) on extruder response and the structural characteristics of high-moisture plant-protein extrudates. The results showed that specific mechanical energy of the extruder decreased from 147.06 kJ/kg to 116.14 kJ/kg, which reduced the energy consumption of the extruder and was beneficial for the application of hydrated wheat gluten with strong viscoelasticity during the extrusion process. Texturization degree that characterized the fibrous structure formation of high-moisture plant-protein extrudates reduced from 1.70 to 1.05. The hardness and chewiness decreased, while the springiness of the extrudates increased. Moderate PHP weakened the cross-linking strength and viscoelasticity of the extrudates, which can improve the problem of the excessively dense texture of high-moisture plant-protein extrudates. Meanwhile, PHP improved protein extractability and increased immobilized water and free water content in the extrudates.

Molecular imprinting of rice husk-derived mesoporous silica for purification and determination of zearalenone

Zearalenone (ZEN) is one of the most prevalent mycotoxins worldwide, yet the extraction and determination of ZEN remain challenging due to difficulties in its purification from the food matrix. In this study, rice husk-derived mesoporous silica (MS) particles were surface-modified with molecularly imprinted polymers (MS@MIPs). The MS@MIPs featured a dense and homogeneous texture with an average particle size of ca. 550 nm, which had an imprinting factor of 5.17 for ZEN. When applied in solid phase extraction (SPE) by packing MS@MIPs and MS (80:20) in a polypropylene column (MIP-SPE), the recovery rate for ZEN deliberately spiked in maize extract reached 94.34%. This was dedicated to facile detection of ZEN by high-performance liquid chromatography with a fluorescence detector (MIP-SPE-HPLC-FLD) showing a linear response to ZEN at 5.0–100 μg/kg with a good R2 of 0.991 and excellent limit of detection and limit of quantification of 1.5 μg/kg and 5.0 μg/kg, respectively. Furthermore, MIP-SPE had good stability with high recovery (≥87.7%) after 5 repeated operations. The results indicated that the MIP-SPE-HPLC-FLD was a facile method for the accurate determination of ZEN in maize.

Exploring the potential of drill cuttings for reservoir characterization: A case study from the Volga-Ural basin, Russia

The research objectives are to assess the possibility of using drill cutting analysis to obtain information about the mineralogical and geochemical properties of the reservoir rocks. Drill cutting samples were collected from a vertical well that penetrated the Domanik sediments (Semiluksk Formation) in one of the oil fields in the Volga-Ural petroleum province. Thin sections from drill cuttings were examined using an optical polarizing microscope (Axio Imager A2). X-ray diffraction (XRD) analyses were performed using a Brucker D2 Phaser X-ray powder diffractometer. Thermophysical properties were studied using an STA 449 F3 Jupiter instrument. The pyrolytic studies were performed using the Rock-Eval method. Visual inspection showed that the studied sediments are alternations of carbonates and siliceous-carbonate rocks. Thin section examinations revealed that the carbonates are mainly limestone (mudstone and wackestone) and are characterized by a dense texture and up to 30 % organic residues. The siliceous-carbonate rocks are dominated by siliceous mudstones and are characterized by dark colours, layered structure, and an enrichment in organic matter. XRD analyses showed that the carbonate rocks are mainly composed of calcite, dolomite, quartz, feldspar, and mica, which are minor components. The siliceous-carbonate rocks are dominated by quartz, followed by calcite, although they also contain feldspars, mica, dolomite, and pyrite as impurities. According to the simultaneous thermal analysis, the average total hydrocarbon in the carbonate and siliceous-carbonate rocks is 13.6 % (for the core samples) and 11.5 % (for the drill cutting samples). The content of heavy hydrocarbons in the rocks is higher than the content of light hydrocarbons, indicating the immature nature of organic matter. Kerogen is found sporadically in siliceous-carbonate rocks. According to the pyrolytic studies, average S1 is 4.4 mg/g and average S2 is 19.8 mg/g (for the core samples); average S1 is 2.1 mg/g and average S2 is 17.8 mg/g (for the drill cutting samples), which indicated that the studied sediments have very good to excellent generation potential. The average Tmax of 425.7 °C (for the drill cutting samples) and 427.9 °C (for the core samples) indicate immature organic matter that generated only heavy oils. Comparing the results of the analysed drill cutting samples with the results of the analysed core analysis from the same reservoir interval in the neighbouring wells showed a good correlation, which proves that this technique is a valid tool that provides an alternative, cost-effective method to determine the rock's characteristics from drill cuttings.

Exploring the Sensory Characteristics of the Soybean Spreads Enhanced with Vegetables and Spices

Transitioning to a plant-based diet presents a number of complex ethical, environmental, and health-related considerations. This trend is not only reshaping consumer diets, but also steering the food industry towards the development of new plant-based products. The primary aim of this study was to examine and identify the sensory similarities and differences in soybean spreads consisting of vegetable purées—specifically, beetroot, pumpkin, broccoli, and carrot—with the addition of spices such as marjoram and cumin. The sensory assessment was conducted using the Quantitative Descriptive Analysis (QDA). Twenty-three descriptors were selected and defined following the profiling procedure. The sensory properties of soy-based spreads have been significantly altered by the addition of vegetable purées and spices. Adding vegetable purées reduced the intensity of soybean odour and flavour, lowered fatty notes, and resulted in a less dense texture, while enhancing vegetable odour and flavour. This also improved the moisture content and overall sensory quality of the spreads. Although spices did not notably enhance these sensory attributes, soy-based vegetable spreads remain an attractive option for unique vegetarian finger foods and lunch dishes, catering to diverse consumer preferences. The addition of vegetable purées and spices to spreads creates opportunities for innovative and flavourful plant-based options.

Visual identification of three kinds of human decidual tissues from elective termination of pregnancy

IntroductionThe decidua can be classified into the decidua basalis, decidua capsularis and decidua parietalis. This study aimed to visually identify these three kinds of decidual tissues from fresh samples obtained in early pregnancy based on their macroscopic appearances, which can be discerned visually. MethodsDecidual samples were collected from 15 pregnant women between 6 and 8 weeks of gestation after elective termination of pregnancy. We identified the three different kinds of fresh decidual tissues in early pregnancy according to their different macroscopic appearances by only the naked eye. H&E staining, in situ immunofluorescence and flow cytometry were performed to confirm the accuracy of this method. ResultsWe developed a method to discern the three different kinds of decidual tissues according to their individual macroscopic features. We found that the decidua parietalis was a thick tissue with less blood, with one side being intact epidermis and the other side being rough tissue. The decidua basalis had rough surfaces, a dense texture and high blood content. The decidua capsularis was a thin membrane tissue with or without blood clots. CK+/HLA-G+ extravillous trophoblast cells (EVTs) and heme oxygenase-1+ (HMOX1+) decidual macrophages were present in large quantities in the decidua basalis and decidua capsularis but were nearly undetectable in the decidua parietalis. We also found a wide distribution of endovascular extravillous trophoblast cells (enEVTs), which participate in spiral artery remodelling in the decidua basalis. DiscussionWe successfully identified three kinds of human decidual tissues from early pregnancy with the naked eye for the first time. This breakthrough method will greatly assist studies related to decidua during early pregnancy.

CLASH: Complementary Learning with Neural Architecture Search for Gait Recognition.

Gait recognition, which aims at identifying individuals by their walking patterns, has achieved great success based on silhouette. The binary silhouette sequence encodes the walking pattern within the sparse boundary representation. Therefore, most pixels in the silhouette are under-sensitive to the walking pattern since the sparse boundary lacks dense spatial-temporal information, which is suitable to be represented with dense texture. To enhance the sensitivity to the walking pattern while maintaining the robustness of recognition, we present a Complementary Learning with neural Architecture SearcH (CLASH) framework, consisting of walking pattern sensitive gait descriptor named dense spatial-temporal field (DSTF) and neural architecture search based complementary learning (NCL). Specifically, DSTF transforms the representation from the sparse binary boundary into the dense distance-based texture, which is sensitive to the walking pattern at the pixel level. Further, NCL presents a task-specific search space for complementary learning, which mutually complements the sensitivity of DSTF and the robustness of the silhouette to represent the walking pattern effectively. Extensive experiments demonstrate the effectiveness of the proposed methods under both in-the-lab and in-the-wild scenarios. On CASIA-B, we achieve rank-1 accuracy of 98.8%, 96.5%, and 89.3% under three conditions. On OU-MVLP, we achieve rank-1 accuracy of 91.9%. Under the latest in-the-wild datasets, we outperform the latest silhouette-based methods by 16.3% and 19.7% on Gait3D and GREW, respectively.

Protein Characterization in Edible Coating for Snack Bar Enriched with Spirulina

Spirulina, renowned for its impressive protein content of 55-70% of dry weight, surpasses commonly used plant sources like soybeans, peanuts, or cereals. However, Spirulina snack bars, with their inherent texture, may face challenges like moisture absorption and microbial growth. In this context, edible coatings emerge as a solution to prevent moisture ingress, microbial growth, and preserve the bars. This study delves into analyzing the protein content of edible coatings, specifically maltodextrin with a 6% concentration and 1% gelatin, aiming to assess their efficacy in safeguarding against ambient moisture and oxygen. The findings reveal that the snack bar with the specified coating concentration showcases enhanced visual appeal and a denser texture. Protein analysis using SDS PAGE identifies bands with molecular weights of 17kDa, 25kDa, and 35kDa, likely corresponding to αs-CN and β-CN proteins. Chromatogram analysis of the Spirulina snack bar using the HPX-87H column unveils a peak at 6.195 minutes in the methanol extract, indicating abundance in α-tocopherol, a vitamin E variant. This comprehensive exploration underscores the potential of edible coatings, providing insights into their role in preserving Spirulina snack bars and contributing to food industry advancements.

Intensifying separation of Pb and Sn from waste Pb-Sn alloy by ultrasound-assisted acid leaching: Selective dissolution and sonochemistry mechanism

Clean and efficient extraction and separation of precious metals from discarded Pb-Sn alloy is critical to the sustainable utilization of solid waste resources. Dense oxide layer and compact alloy texture in the waste Pb-Sn alloy pose challenges to the effective leaching process. Ultrasonic waves are demonstrated to improve separation efficiency via the favorable physical and chemical effects in solution system. In this study, ultrasound-assisted leaching technology is attempted to rapidly and selectively extract Pb from the waste Pb-Sn alloy, and gives emphasis on ultrasonic electrochemical behaviors. The Eh-pH diagrams of Sn-H2O and Pb-H2O systems were firstly analyzed to lay the selective dissolution foundation. It’s indicated that oxidizing HNO3 lixiviant is suitable to realize the selective separation of Pb. Both Sn and Pb can be dissolved to ionic Sn2+ and Pb2+ in the HNO3 solution. However, Sn2+ rapidly oxidizes to Sn4+ and Sn4+ further hydrolyzes to insoluble SnO2, which will agglomerate on unreacted materials to limit internal metal leaching in conventional leaching process. Due to the vibratory stripping of oxide layer by physical effect of ultrasound, the conventional acid leaching time for Pb extraction can be halved with the ultrasound assistance. About 99.12 % Pb and only 0.1 % Sn are dissolved in ultrasound-assisted leaching under the following optimal parameters: 0.5 mol/L HNO3, leaching temperature of 80 °C, time of 30 min, liquid-to-solid ratio of 20 mL/g, and ultrasound intensity of 0.52 W/cm2. Leaching kinetics of Pb, phase transition, microstructure evolution, Pb-Sn galvanic corrosion and dissolution polarization curve were studied to determine the ultrasonic enhanced dissolution mechanism. Notably, Pb and Sn form a microcorrosion galvanic cell in which Sn acts as a cathode and is protected while the Pb undergoes intensifying corrosion as the anode giving rise to the higher Pb dissolution efficiency. Eventually, it’s suggested that Pb can be rapidly extracted and separated from the waste Pb-Sn alloy during the ultrasound-assisted HNO3 leaching process via the ultrasound physical and chemical effects, especially the sonochemistry aspect of intensified spot corrosion and galvanic corrosion. The proposed ultrasonic electrochemical corrosion in this work were applicable to the extraction of valuable metals from various waste alloys through leaching method.

Quantitative analysis of microglia morphological changes in the hypothalamus of chronically stressed rats

Based on the successful establishment of a rat model of chronic restraint stress, we used multiple algorithms to quantify the morphological changes of rat hypothalamic microglia from various perspectives, providing a pathomorphological basis for the subsequent study of molecular mechanisms of hypothalamic stress injury, such as neuroinflammation. To verify the successful establishment of the chronic stress model, an enzyme-linked immunosorbent assay was performed to detect serum glucocorticoid levels. Microglia labeled with Iba1 in frozen sections of rat hypothalamus were scanned and photographed at multiple levels using confocal microscopy. Subsequently, images were processed for external contouring and skeletonization, and morphological indices of microglia were calculated and analyzed using fractal, skeleton, and Sholl analysis. In addition, the co-expression of CD68 (a marker that can reflect phagocytic activity) and Iba1 was observed by immunofluorescence technique. Compared with the control group, microglia in the chronic stress group displayed reduced fractal dimension and lacunarity, increased density and circularity, enlarged soma areas, and shortened and reduced branches. Sholl analysis confirmed the reduced complexity of microglia following chronic stress. Meanwhile, microglia CD68 increased significantly, indicating that the microglia in the chronic stress group have greater phagocytosis activity. In summary, chronic restraint stress promoted the conversion of microglia in the rat hypothalamus to a less complex form, manifested as larger soma, shorter and fewer branches, more uniform and dense texture, and increased circularity; indeed, the shape of these microglia resembled that of amoeba and they displayed strong phagocytosis activity.