High Texture Research Articles

THE IMPACT OF STARTER CULTURES ON QUARK TYPE CHEESE PRODUCTION

This study was conducted to investigate the effect of starter cultures on the physicochemical and microbiological properties, texture, yield, and consumer preferences of quark type cheese. For this purpose, three different quark cheeses were manufactured by using commercial starter cultures. The microbiological, physicochemical, textural, and sensory properties of the cheese samples were determined at 1st, 14th, and 28th days of the storage period. The results showed that the kind of starter culture used in production influences the composition and yield of the obtained quark cheeses. It has been determined that the use of kefir culture in quark cheese production influences the moisture and water holding capacity, and as a result, improves its spreadability. Also, the sensory analysis exhibited that cheese produced with kefir culture had higher texture and taste-flavor acceptability. The study indicates that kefir culture may be successfully used in quark cheese production.

Exploring the toughening mechanisms of PyC interphase in SiCf/SiC composites through molecular dynamics and mesoscale stochastic simulations

The introduction of pyrolytic carbon (PyC) interphase in SiCf/SiC composites significantly improves their toughness, primarily by deflecting matrix cracks, while the underlying toughening mechanisms toward various PyC microstructures remain mysterious due to the challenges in experimentally observing microscopic deformations within PyC. This paper addresses this gap by constructing distinct PyC models based on orientation angle (OA), a key experimental characteristic, and then conducting Mode I loading simulations on SiCf/PyC/SiC systems by molecular dynamics (MD). Results indicate that as OA increases, the deformation behavior of PyC transits from multilayer sliding to delamination, which correlates to a reduction in the fracture energy of SiCf/PyC/SiC systems. Energy dissipation models are established for two microscopic deformation patterns as multilayer sliding and delamination based on homogenization theory, with results demonstrating that the energy dissipation caused by multilayer sliding within PyC surpasses that of delamination. Furthermore, mesoscale stochastic simulations of crack propagation in PyC with different textures are carried out to obtain crack path configurations and corresponding energy dissipations. The outcomes highlight the superior toughening effect of high texture (HT) PyC over medium texture (MT) and low texture (LT) PyC due to longer crack path within HT PyC, aligning well with experimental findings. This study provides valuable insights into cracking through PyC with varying textures, offering a foundation for optimizing PyC coating processes in SiCf/SiC composites to enhance performance.

Date seed by-products as source of bioactive ingredient for healthy cookies

Date seeds are byproducts of date processing and lack value beyond livestock feed. Our work focused on utilizing seed flours (defatted flour, F1, and ethanol-extracted defatted flour, F2) and testing their incorporation into cookies at different wheat flour substitution (10% and 30%). Flours and cookies were analyzed for their proximal and phenolic compositions, and antioxidant activity. Baking behavior, appearance and sensory studies were performed for cookies. Seed flours could be considered as food ingredients for their fiber content (84%), antioxidant properties (631–770 mmol TE/kg), and energy value (22–25 Kcal/100g). F1-Cookies had a higher texture (27–30 N) and phenolic content (0.5–1 g/kg) and a darker color. These characteristics made them less acceptable to the panelists, although their antioxidant activity was high (48–78 mmTE/kg). F2-Cookies were similar in texture (18–19 N) to the control, their color was intermediate between the control and F1, their phenolic content was about half of F1 (0.26–0.49 g/kg), and their antioxidant activity was higher than control (31–50 mmTE/kg). In three out of five parameters evaluated by the panel (odor, taste and texture), there were no significant differences between control and F2-10%. F2 flour would be an interesting product for baked good formulation, as F2-cookies had high fiber content, antioxidant activity, and good consumer acceptability. F1, but only at its lowest dosage (10%), could also be considered a valuable ingredient. This study demonstrated the potential use of date seeds for human consumption, producing healthy and nutritious foods that could promote economic and social development in date producing regions.

Chemical and Organoleptic Analysis of Tiliaya Products Fortified Yellow Pumpkin (Cucurbita moschata Durch)

Tiliaya is a type of traditional food in Gorontalo. Its existence has been around for a long time and has become a hereditary legacy in Gorontalo and is only found in traditional ceremonies or certain religious rituals. In addition, most of the tiliaya circulating in the market are tiliaya without certain nutritional fortifications. The purpose of this lab is to find out the characteristics of tiliaya fortified with pumpkin. The design used was a completely randomized design (CRD) with 1 control and 3 treatments. Each control and treatment will be repeated 3 times. T0 without adding pumpkin, T1 adding 10% pumpkin, T2 adding 20% ​​pumpkin and T3 adding 30% pumpkin. The test parameters carried out included Vitamin C Test, Fiber Content and Organoleptic Preference Test. Based on the results, it was found that the increase in vitamin C content was from 2.93 to 5.86 mg/100, While the organoleptic characteristics of tiliaya include taste, color, texture and aroma. Tiliaya with the addition of 10% extract had the highest texture, color and aroma taste values.

Does texture analysis classify semantic dementia from Alzheimer’s disease better than volumetric analysis?

AbstractBackgroundTexture analysis may capture subtle changes in the gray matter more sensitively than volumetric analysis. We aimed to investigate the patterns of neurodegeneration in semantic dementia (SD) and Alzheimer’s disease (AD) by comparing the temporal gray matter texture and volume between cognitively normal controls and older adults with SD and AD.MethodWe enrolled all participants from three national university hospitals in Korea. We obtained T1‐weighted magnetic resonance images and compared the gray matter texture and volume of regions of interest (ROIs) between the groups using analysis of variance with Bonferroni posthoc comparisons. We also developed models for classifying SD, AD and control groups using logistic regression analyses, and validated the models using receiver operator characteristics analysis.ResultCompared to the AD group, the SD group showed lower volumes in five ROIs (bilateral temporal poles, and the left inferior, middle, and superior temporal cortices) and higher texture in these five ROIs and two additional ROIs (right inferior temporal and left entorhinal cortices). The performances of both texture‐ and volume‐based models were good and comparable in classifying SD from NC (mean area under the curve [AUC] = 0.914 for texture; mean AUC = 0.894 for volume). However, only the texture‐based model achieved a good level of performance in classifying SD and AD (mean AUC = 0.775 for texture; mean AUC = 0.658 for volume).ConclusionTexture may be a useful neuroimaging marker for early detection of SD in older adults and its differentiation from AD.

A Preliminary Study on the Use of Protein Isolate Produced From Trout in Tarhana Soup

The aim of this study is to use protein isolate that produced from fillet trout by pH shifting (acid) processes, in tarhana soup as protein enrichment. Three different soup groups were prepared; control (C): without isolate; 3.5% protein isolate added (T1) and 7% protein isolate added (T2). For sensory characteristics of soups, groups were compared by using color and sensory analysis by panelists. According to the sensory analysis results, the highest texture, odor and general acceptability values (7.38; 7.50 and 7.50, respectively) were reported in T1 while, these values were the lowest in C (6.50, 7.13 and 7.13, in order). When the results were evaluated in general, it was determined that there was no significant difference in terms of general acceptability in both isolate-added soup groups compared to the C. Test score of T1 is higher than T2 in terms of texture, it was determined that the isolate added groups were better than the C. With this preliminary study, it was determined that the fish protein isolate did not have a negative effect on the sensory properties of tarhana. More research is needed to establish the impact of additional fish protein isolate on the functional and biochemical quality of tarhana.

Proportion of Oatmeal and Gambir Masks as an Aging Facial Skin Care

Skin aging is a phenomenon of decreasing the size, number of skin cells and changes in the organic function of the skin caused by a process of deterioration of the skin structure and a decrease in normal skin function. This study aims to make cosmetic face masks for the care of aging facial skin using a mixture of oatmeal and gambir ingredients. This research uses an experimental method with a quantitative descriptive approach. The types of data sources used are primary data and data collection techniques using observation and documentation methods. This study used organoleptic tests (texture, aroma, adhesion), hedonic tests (panelists' preferences) and laboratory tests. The panelists used consisted of 7 people. The proportion of oatmeal and gambir masks used is 20:80, 30:70 and 40:60. In the organoleptic test, the highest texture was found in the ratio of 20:80, in the highest aroma test it was found in the comparison of 20:80 and in the highest adhesion test it was found in the ratio of 20:80 and 30:70. Meanwhile, the highest hedonic test results (panelists' preferences) are found in a ratio of 30:70. In the results of laboratory tests on the proportion of masks of 30:70, there was a content of vitamin C as much as 11.66% and vitamin A as much as 0.26% in 100 gr of mask samples.

Physical and sensory properties of soy-based ice cream formulated with cold-pressed high oleic low linolenic soybean oil.

The effect of cold-pressed SOYLEIC™ soybean oil (SOYLEIC) on the physical and sensory properties of soy-based ice cream was compared to commercial vegetable oil (COM-VO), commercial high oleic soybean oil (COM-HO), and heavy cream (CREAM). Fat sources had no significant effect on viscosity and fat globule size distribution of ice cream mixes. Ice cream made with COM-VO had the lowest overrun (p <0.05) and higher degree of fat destabilization; however, no difference in hardness was found. Despite similar melting rate, the shape retention behavior during melting was different for SOYLEIC, COM-VO, and COM-HO compared to CREAM. No significant differences were found in texture attributes except mouth coating, which was higher for CREAM than COM-HO and SOYLEIC (p <0.05). There was no significant difference in flavor attributes between SOYLEIC and CREAM, while COM-VO and COM-HO had higher off-flavor intensities (p <0.05). Consumer acceptability results revealed that SOYLEIC and CREAM had significantly higher flavor liking and overall liking scores than COM-VO and COM-HO (p <0.05). SOYLEIC and CREAM also had higher texture liking than COM-VO (p <0.05). Overall, liking had the highest positive significant correlation with flavor liking (r=0.996). PRACTICAL APPLICATION: Cold-pressed HOLL soybean oil has the potential to be used in formulating plant-based frozen desserts with equivalent texture but more acceptable flavor.

Textural and Volumetric Changes of the Temporal Lobes in Semantic Variant Primary Progressive Aphasia and Alzheimer's Disease.

Texture analysis may capture subtle changes in the gray matter more sensitively than volumetric analysis. We aimed to investigate the patterns of neurodegeneration in semantic variant primary progressive aphasia (svPPA) and Alzheimer's disease (AD) by comparing the temporal gray matter texture and volume between cognitively normal controls and older adults with svPPA and AD. We enrolled all participants from three university hospitals in Korea. We obtained T1-weighted magnetic resonance images and compared the gray matter texture and volume of regions of interest (ROIs) between the groups using analysis of variance with Bonferroni posthoc comparisons. We also developed models for classifying svPPA, AD and control groups using logistic regression analyses, and validated the models using receiver operator characteristics analysis. Compared to the AD group, the svPPA group showed lower volumes in five ROIs (bilateral temporal poles, and the left inferior, middle, and superior temporal cortices) and higher texture in these five ROIs and two additional ROIs (right inferior temporal and left entorhinal cortices). The performances of both texture- and volume-based models were good and comparable in classifying svPPA from normal cognition (mean area under the curve [AUC] = 0.914 for texture; mean AUC = 0.894 for volume). However, only the texture-based model achieved a good level of performance in classifying svPPA and AD (mean AUC = 0.775 for texture; mean AUC = 0.658 for volume). Texture may be a useful neuroimaging marker for early detection of svPPA in older adults and its differentiation from AD.

Physical Quality of Fresh Cayenne Pepper (Capsicum frutescens L.) with Different Types of Packaging during Low Temperature Storage

Cayenne pepper (Capsicum frutescens L.) is classified as a horticulture product that easly damaged and it can only survive for 2-3 days in room temperature conditions. In maintaining the quality and self life time of fresh cayenne pepper during storage it is recommended to use the packaging and storage at low temperature. The purpose of this study is to analize the effect of packaging type and storage length on the physical quality of fresh cayenne pepper during low temperature storage (5°C). This study used a complete randomized design method with two factors, each of which consisted of 3 levels, namely storage time (4, 8, and 12 days) and type of packaging (vacuum pack, perforated polypropyline plastic, and wrap plastic). The data were analized by using factorial Anova two mix factors test (α= 5%) and was followed up by Tukey test. The results showed that the best packaging was found in perforated polypropylene plastic with the lowest moisture content 76.45%, the lowest weight loss 3.87%, the highest texture (hardness) 0.027 N/mm², the highest lightness (L*) 44.52, the lowest redness (a*) 26.7, the lowest yellowness (b*) 10.97, the lowest ΔE 23.47, and the lowest water activity 0.889. Physical quality of fresh cayenne pepper can last up to 12 days at low temperature storage (5°C) using perforated polypropylene plastic. Keywords: Cayenne pepper, packaging, storage, low temperature, physical quality.

Ultrafast high-temperature sintering of dense and textured alumina

Crystallographic texture engineering in ceramics is essential to achieve direction-specific properties. Current texture engineering methods are time-consuming, energy extensive, or can lead to unnecessary diffusion of added dopants. Herein, we explore ultrafast high-temperature sintering (UHS) to prepare dense and textured alumina using templated grain growth (TGG). From a slurry containing alumina microplatelets coated with Fe3O4 nanoparticles dispersed in a matrix of alumina nanoparticles, green bodies with oriented microplatelets were prepared using magnetic assisted slip casting (MASC). The effects of the sintering temperature, time and heating rate on the density and microstructure of the obtained ceramics were then studied. We found that TGG occurs for a temperature range between 1640 and 1780 °C and 10 s sintering time. Sintering at 1700 °C for 10 s led to dense and textured alumina with anisotropic grains thanks to the Fe3O4 coating, which did not have the time to diffuse. The highest texture and relative density were obtained with a heating rate of ~5500 °C/min, leading to texture-dependent anisotropic mechanical properties. This study opens new avenues for fabricating textured ceramics in ultra-short times.

Addition of Kecombrang Flower Flour (Etlingera elatior) to the Characteristics of Red Beans Noodles

Along with the times, many types of food have changed both in terms of taste, appearance, and presentation. One of the foods that are much favored by the community and easy to serve is wet noodles. Wet noodles supplemented with 10% red bean flour is expected to help fulfill protein. Moisture content of wet noodles reaches 52% so that the shelf life is quite short. Kecombrang can be used as a preservative to extend the shelf life of wet noodles. This research was conducted to obtain physical, chemical, organoleptic and shelf life characteristics based on the Total Plate Count (TPC) of red bean wet noodles. The experimental design used in this study was a single factor Randomized Block Design (RAK), namely the addition of kecombrang flower flour with 5 treatment levels, namely 1%, 2%, 3%, 4% and 5%, from 100 g flour (90 g wheat flour + 10 g red bean flour). Each treatment was repeated 3 times to obtain 15 experimental units. The results showed that the highest water content was 64,33%, the brightest color was in the 1% treatment with a value of 5Y 9/3, while the darkest color was in the 5% treatment with a value of 5Y 7/2, the highest texture was 37,78 mm/g/ s, the highest protein was 14,09%, the highest ash content was 1,17%, the concentration of addition of 5% kecombrang flower flour was able to extend the shelf life of red bean wet noodles for 48 hours, organoleptic characteristics showed that the panelist acceptance rate was at a concentration of 1% - 3 % based on the overall rating. Keywords: Kecombrang, Red beans, Shelf life, Wet Noodles.

Incorporation of Urea Fertilizer and Activated Carbon in Carboxymethyl Cellulose-Based Bioplastics

The high mobility of urea as a nitrogen nutrient in the soil leads to inefficient absorption by plants. Hence efforts to design a slow-release fertilizer (SRF) are significant. This paper reports the incorporation of urea fertilizer with carbon or zeolite in a bioplastic made of carboxymethyl cellulose as the matrix. The bioplastics were made by mixing the zeolite or activated carbon suspensions into a sodium carboxymethyl cellulose (Na-CMC) gel. Glycerol was then added as a plasticizer. Six variations of bioplastics were prepared, namely CMC-urea 0.5 and 1.0, CMC-urea-zeolite, CMC-urea-zeolite-glycerol, CMC-urea-activated carbon, and CMC-urea-activated carbon-glycerol. The weight ratio of CMC and urea fertilizer was kept constant at 2:1 since the resulted bioplastics showed higher texture transparency and homogeneity than those of bioplastics with a weight ratio of CMC to urea 1:1. The addition of zeolite increased the tensile strength of the bioplastics by about two times. While, the glycerol addition improved the elongation at break. The release of urea from the bioplastics was slower for bioplastics with zeolite than with activated carbon. The composite bioplastics may serve as a slow-release urea for agriculture.

Evaluation of the Suitability of Tigernut Milk and Tigernut-Cow Composite Milks for Yoghurt Production

The cost of animal milk used in yoghurt production in Nigeria has continued to rise, making the price of yoghurt to become prohibitive. This study investigated the suitability of tiger nut milk for yoghurt production. Five milk formulations prepared from tiger nut milk and cow milk were used to produce yoghurts. pH and titratable acidity (TA) of the milks and yoghurts were determined. The yoghurts were assessed for total plate count (TPC), total fungal count (TFC), fat content and sensory properties. Sensory properties were evaluated by a 10-man taste-panel using a 5-point hedonic scale. pH values of the yoghurts ranged from 3.94 – 4.68. TA values ranged from 0.56 – 0.64. TPC of the yoghurts ranged from 1.0 x 102 – 1.3 x 103 cfu/ml while TFC ranged from 0.1 x 101 – 0.3 x 101. The microbial counts of the yoghurt samples were within acceptable safety limits. The yoghurts were generally acceptable to the panelists. There were significant (P &lt; .05) differences in the sensory scores for appearance, taste, texture, and overall acceptability. Tiger nut-cow milk (75:25) yoghurt had the highest appearance and taste scores while tiger nut milk (100) yoghurt had the highest texture and overall acceptability scores. Tiger nut milk (100) yoghurt was the most preferred yoghurt with an overall acceptability score of 4.8±0.42 followed by tiger nut-cow milk (75:25) yoghurt. Yoghurts analysed had fairly high fat contents. The study showed that tiger nut milk and tiger nut-cow milk composites could be used as alternatives to cow milk for yoghurt production.

Physico-Chemical Properties of Red Pepper (Capsicum annuum L.) as Influenced by Different Drying Methods and Temperatures

An experiment was carried out in the laboratories of the Department of Food Engineering, Department of Vegetable Science, and Department of Plantation Spices Medicinal and Aromatic crops, Bidhan Chandra Krishi Viswavidyalaya (BCKV), West Bengal, India. The work was performed during 2018–2019 and 2019–2020 with different drying methods including sun drying, solar drying and oven drying. In oven drying, different temperatures such as 50, 55, 60, 65, and 70 °C were considered. A randomized complete block design (RCBD) was designed with seven treatments and three replications. Experimental results were significantly varied among the treatments as influenced by different drying methods and temperatures. Minimum time taken (480 min) to reach safe moisture content was recorded in T7 (oven drying at 70 °C), whereas maximum values in color components such as L* value (24.55), a* value (32.14), b* value (20.53), and pungency score (7.85) were recorded in T6 (oven drying at 65 °C). However, the highest texture (1180.81) was observed in T1 (sun drying). Biochemical parameters were significantly varied among the treatments. The maximum amounts of ascorbic acid (56.06 mg/100 g) and oleoresin content (10.72) were found in T3 (oven drying at 50 °C), whereas minimum values of biochemical parameters were recorded by T1 (sun drying) and T2 (solar drying) methods, respectively. Mathematical relationships were found in different drying methods and temperatures. Models such as the Lewis, Page, Modified Page, and Henderson and Pabis models were selected to fit the data. Maximum R2 value (0.9835) was found in both the Page and Modified Page models with similar values of drying method and temperature at 65 °C. This value was the highest among all models in all drying temperatures. However, the lowest χ2, and RMSE values (0.000818 and 0.027261, respectively) were recorded with the Page model.

Performance characterization and enhancement mechanism of recycled asphalt mixtures involving high RAP content and steel slag

Reutilization of reclaimed asphalt pavement (RAP) is conducive to achieving carbon peak and neutrality goals and establishing a resources recycling system for road engineering. Previous studies have indicated that recycled asphalt mixtures with RAP content exceeding 30% seem inappeasable in upper surface of asphalt pavement due to their inferior skid resistance and endurance. While steel slag, a solid waste with excellent mechanical properties and high alkalinity, can elevate performances of asphalt mixture. Recycled asphalt mixtures involving 50%, 60% and 70% RAP content and steel slags were prepared firstly, and their road performances were characterized. Properties discrepancies existing in microstructure and geometric characteristics of steel slag and basalt and their interfacial properties with asphalt were discussed. The results indicate that incorporating steel slag in recycled asphalt mixtures with 70% RAP content reveals a desirable performances indexes in contrast to basalt. The adhesion and mechanical performance of recycled asphalt mixtures can be significantly enhanced by steel slag due to its honeycomb porous structure, larger angularity, lower sphericity and higher texture. Steel slag and recycled asphalt demonstrate lower spalling rate under hydrodynamic pressure and larger adhesive destructive force compared with basalt, resulting in superior moisture susceptibility and cracking resistance for recycled asphalt mixtures.

The Effect of Al and Ti Transition Metals on the Wear Resistance of Ceramic Based CrN Coatings; Investigation under Ambient Air and Vacuum Conditions

In the present study, CrN, CrAlN and CrAlTiN coatings were deposited using the cathodic arc evaporation technique. The structural investigations of these CrN based coatings were performed by scanning electron microscopy, energy dispersive spectroscopy, atomic force microscopy, X-ray diffractometer. The hardness and adhesion strength values of coatings were determined via Vickers type microhardness tester and progressive load scratch tester, respectively. The wear performance of samples was established at ambient air and vacuum condition. All coatings grew in the “T zone” growth model and had a dense and columnar structure. The XRD patterns presented predominantly (220), (110), and (111) reflections. It was demonstrated that the quaternary coating had a higher texture parameter as 0.68, which was related to the highest thickness and hardness. Also, CrAlTiN coatings with the smallest mean crystallite size of ∼87 nm showed the best hardness, and this ensured relatively high scratch resistance. CrN and CrAlTiN coatings improved wear performance under ambient air condition but were not striking as under vacuum condition. The quaternary coating had a superior performance in the vacuum condition, but due to the high sensitivity of Ti to oxygen, it fell behind the CrN coating under ambient air condition.

Increasing the quality of anchovy (Stelophorus sp.) with additional concentration of chitosan

Anchovy is a main capture fishery commodity in North Maluku. Currently, the processing activity of anchovy is relatively simple and traditional, consequently, causing anchovy quality to be easily degraded. One solution to overcome the problem is through the addition of chitosan concentration. This study aimed to determine effect of concentration addition of chitosan on quality of water content, protein, fat, carbohydrates, organoleptic and Total Plate Count (TPC) test. Method used in this research was the analysis of water quality test, protein content, fat content, carbohydrate content, calorie content, organoleptic test and TPC test. The study results showed that the highest water content value was 13.65% at 0.1% concentration, the highest protein value was 61.16% at 0.5% concentration, the highest ash content value was 16.5% at 1% concentration, the highest fat value was 3.99% at 1% concentration, and the highest fat value was 3.99% at 1% concentration. The highest carbohydrate content found was 11.94% at 0.1% concentration, and the highest calorific value was 2.51% at 1% concentration. Meanwhile, average organoleptic value of the highest appearance was 6.87% at a 0.3% concentration, the highest odor was 7.55% at a 0.3% concentration, the highest texture was 7.45% at a 0.1% concentration and color was 6.25% at a 0.3% concentration. Results of the TPC tests showed that anchovy with chitosan treatment and without chitosan during storage changed for all treatments. The average TPC value at all concentrations (0.1%, 0.3% and 0.5%) had the lowest TPC value compared to the control.

The morphological characteristics of brick-concrete recycled coarse aggregate based on the digital image processing technique

Recycled coarse aggregates, including crushed brick recycled coarse aggregate (CBRCA) and crushed concrete recycled coarse aggregate (CCRCA), are increasingly used as raw material in building materials. In fact, the morphological characteristics of recycled coarse aggregates take great effect on properties of materials. Therefore, this paper mainly investigates the morphological characteristics and physical properties of brick-concrete recycled coarse aggregate (BCRCA) composed of CBRCA and CCRCA. Morphological characteristics indexes of coarse aggregates including angularity, sphericity, texture and fractal dimension were described by digital image processing technique. The differences of morphological characteristic indexes among recycled coarse aggregates and natural crushed gravel coarse aggregate (NCGCA) were discussed. Results show that CBRCA has the highest void content, crushing index and water absorption among the four types of aggregates. Compared with NCGCA, recycled coarse aggregates have a higher angularity, lower sphericity and higher texture. The fractal dimension of recycled coarse aggregates is higher than NCGCA, indicating the complexity of shape of recycled coarse aggregates. Among the recycled coarse aggregates, CBRCA has the highest angularity and lowest sphericity, and CCRCA has the highest texture. The angularity and texture are significantly influenced by aggregate types. The sphericity and flatness ratio, as well as the angularity and texture have good positive correlation. The fractal dimension and elongation ratio, as well as the fractal dimension and sphericity have negative correlation. By testing two-dimensional indexes including fractal dimension and elongation ratio can easily reflect the morphological characteristics of coarse aggregates. When recycled coarse aggregates is used in building materials, the morphological characteristics should be carefully considered.

Nanostructure and thermal power of highly-textured and single-crystal-like Bi2Te3 thin films

Bi2Te3-based alloys are known to have outstanding thermoelectric properties. Although structure-property relations have been studied, still, detailed analysis of the atomic and nano-scale structure of Bi2Te3 thin film in relation to their thermoelectric properties remains poorly explored. Herein, highly-textured (HT) and single-crystal-like (SCL) Bi2Te3 films have been grown using pulsed laser deposition (PLD) on Si wafer covered with (native or thermal) SiOx and mica substrates. All films are highly textured with c-axis out-of-plane, but the in-plane orientation is random for the films grown on oxide and single-crystal-like for the ones grown on mica. The power factor of the film on thermal oxide is about four times higher (56.8 µW·cm−1·K−2) than that of the film on mica (12.8 µW·cm−1·K−2), which is comparable to the one of the polycrystalline ingot at room temperature (RT). Reduced electron scattering in the textured thin films results in high electrical conductivity, where the SCL film shows the highest conductivity. However, its Seebeck coefficient shows a low value. The measured properties are correlated with the atomic structure details unveiled by scanning transmission electron microscopy. For instance, the high concentration of stacking defects observed in the HT film is considered responsible for the increase of Seebeck coefficient compared to the SCL film. This study demonstrates the influence of nanoscale structural effects on thermoelectric properties, which sheds light on tailoring thermoelectric thin films towards high performance.