Substrate Characteristics Research Articles

Impact of substrate particle size on the digging behavior of the juveniles of the smooth fan lobster Ibacus novemdentatus Gibbes, 1850 (Decapoda: Pleocymeta: Scyllaridae)

Abstract Aquaculture techniques for fan lobsters are still in an early stage of development due to the limited knowledge on their early-benthic stages. As the lobsters are diggers and thus the substrate influences their survival and growth, the physical characteristics of such substrates are a crucial environmental factor in an aquaculture setting. The appropriate size ranges of the substrate particles are nevertheless unknown. We studied the digging behavior of the juvenile of the smooth fan lobster, Ibacus novemdentatusGibbes, 1850, and examined its ability to dig into sand of different particle sizes to determine the optimal substrate conditions. Digging was completed by 100% of the juveniles in fine sand, 85.7% in medium-size sand, 25.7% in medium-coarse sand, and none in coarse sand. Juvenile digging involves three stages: searching for a location to dig, inserting the tail fan, and submerging into the sediment. The median length of time from the beginning of the experiment to the commencement of tail insertion in juveniles that completed digging did not differ significantly (P = 0.97) with the particle size. Juveniles placed on the substrate with medium-size and medium-coarse sand took significantly longer (P < 0.01) from the start of tail insertion to the complete submersion than those on fine sand. Considering the success rates of digging and the time required to complete digging, fine sand was the most appropriate substrate among the tested particle-size ranges. The juveniles that failed to complete the digging repeated a digging position and attempted to insert their tail fan into the sand without submerging. These juveniles took a significantly longer time (P < 0.05) to attempt to insert their tail fan than the juveniles that successfully completed digging, suggesting that juveniles placed on inappropriate substrates may spend more energy on digging and become more stressed.

Coalescence Mechanism Induced by Different Wetting States of Ti and Al Droplets on Rough Surfaces.

There is currently increasing interest in droplet transportation and coalescence on rough surfaces. However, the relationship among wettability, coalescence mode, and substrate characteristics (roughness and nanopillar height) remains unclear. In this work, two coalescence modes, climbing coalescence and contacting coalescence, are first observed in the dynamic behaviors of Ti and Al droplets on rough substrates. Due to the nonsynchronized wetting state transition of the droplets, the coalescence mode with increasing substrate characteristics differs, transitioning from contacting coalescence to climbing coalescence and then returning to the contacting mode. In general, the mode of coalescence correlates closely with the respective wetting states. Typically, Ti and Al droplets coalesce in the contacting mode when they have the same wetting state, but if they have different wetting states, they coalesce in the climbing mode. Our results emphasize the complicated relationship between the surface structure and the wettability of droplets, which could provide insights into self-assembly, three-dimensional printing, and microfluidic devices.

Multiscale Models of CVD Process: Review and Prospective.

Chemical vapor deposition (CVD) is a crucial technique in the preparation of high-quality thin films and coatings, and is widely used in various industries including semiconductor, optics, and nuclear fuel, due to its operation simplicity and high growth rate. The complexity of the CVD process arises from numerous parameters, such as precursor chemistry, temperature, pressure, gas flow dynamics, and substrate characteristics. These multiscale parameters make the optimization of the CVD process a challenging task. Numerical simulations are widely used to model and analyze the CVD complex systems, and can be divided into nanoscale, mesoscale, and macroscale methods. Numerical simulation is aimed at optimizing the CVD process, but the inter-scale parameters still need to be extracted in modeling processes. However, multiscale coupling modeling becomes a powerful method to solve these challenges by providing a comprehensive framework that integrates phenomena occurring at different scales. This review presents an overview of the CVD process, the common critical parameters, and an in-depth analysis of CVD models in different scales. Then various multiscale models are discussed. This review highlights the models in different scales, integrates these models into multiscale frameworks, discusses typical multiscale coupling CVD models applied in practice, and summarizes the parameters that can transfer information between different scales. Finally, the schemes of multiscale coupling are given as a prospective view. By offering a comprehensive view of the current state of multiscale CVD models, this review aims to bridge the gap between theory and practice, and provide insights that could lead to a more efficient and precise control of the CVD process.

Comparative Evaluation of Methane Yield from Continuous and Batch Fermentative Processing of Selected Agrowaste

This study investigated the influence of different agrowaste compositions on methane yield in batch and continuous operational modes, highlighting the significance of substrate characteristics in determining the efficiency of methane production. It comparatively assessed the methane yield derived from continuous and batch fermentative processing of the following agrowaste; Cassava peels (A), Maize husks (B), Pig Slurry (C), and composite (D) that represents the co-digestion of the aforementioned A, B & C. Eight digesters were used in all, two anaerobic systems for each substrate, [I.e one operating in a batch mode (1) and the other in a continuous mode (2)]. The proximate properties of the substrates were determined and gas production rates were monitored over the experimental period of 45 days. Gas analysis of the generated gas revealed mainly methane and CO2, with concomitant organic compounds like; Ethanol, Methanol, Acetic Acid, Acetone, etc. Minute quantities of Phenol and Lactic Acid were mainly found in the gas generated from Cassava peels. The average percentage value of Co-digested substrates (D) yielded higher gas volume of 78.263±4.54, followed by C (74.263±4.65), B (70.240±4.38), and A (56.090±3.50). The results also revealed that the continuous fermentative process demonstrated a more stable and consistent methane production rate compared to the batch system, attributed to its steady-state operational mode and continuous substrate feed input. However, modeled graphical results showed that batch fermentation system produced higher gas yield (for all the substrates) between days 29-39 before it recorded a sharp decline curve, attributed to the reduction in substrate availability.

Influence of bottom supporting columns and cooling rate on the surface shape characteristics of sapphire substrates

The manufacturing process of sapphire substrates involves several key steps, including epitaxy, annealing, cutting, and processing. Among these, epitaxy and annealing are particularly crucial. The temperature variances along both the longitudinal and transverse axes within the furnace during the crystallization process play a significant role in determining the crystallization rate and internal structure of sapphire crystals. Furthermore, annealing sapphire serves to alleviate internal stress, enhance crystal structure, optimize physical properties, improve optoelectronic characteristics, enhance surface quality, and increase overall yield. This step is paramount in enhancing the performance and application value of sapphire materials. In order to investigate and optimize the effects of different thermal conductivities of support columns at the base and various annealing procedures on the surface characteristics of sapphire substrates, thereby improving product quality, this study conducted research by utilizing support columns made of different materials and carefully controlling the cooling rate parameters for sapphire. The findings revealed that using graphite as the base support column for the crystal furnace can reduce both the longitudinal and transverse temperature gradients within the furnace, consequently promoting crystal growth and enhancing the quality of sapphire ingots. Additionally, sapphire chips annealed using the rapid one-step annealing program exhibited the highest average warpage and bending rate variation, reaching 2.0 μm, and the average dislocation density was half that of conventionally produced chips, at 108.89 pits/cm2.

Effects of Time-Elapsed Bleaching on the Surface and Mechanical Properties of Dentin Substrate Using Hydrogen Peroxide-Free Nanohydroxyapatite Gel.

There is a critical need to address concerns surrounding the potential impact of bleaching gels specifically on the tooth substrate. Therefore, this laboratory investigation aimed to assess the impact of a hydrogen peroxide (HP)-free bleaching (HiSmileTM) in comparison to an HP-based bleaching (Opalescence RegularTM) on the surface and mechanical characteristics of tooth substrate. Sixty sound human premolar teeth were sectioned to produce dentin fragments and divided into two primary groups based on the bleaching agent used. Each group was subdivided into three subgroups (n = 10) per distinct bleaching regimens: (T1) fragments underwent a 7-day immersion in distilled water at 37°C without any bleaching treatment, (T2) fragments underwent a 7-day immersion in distilled water at 37°C, with the application of bleaching gel occurring on the seventh day for 10minutes, and (T3) fragments underwent a bleaching regimen for seven consecutive days, each session lasting for 10minutes. The initial and final evaluations of surface roughness, nano-hardness, and elastic modulus were performed. Following the bleaching regimens of T3, a composite stub was fabricated on the dentin fragments for the shear bond strength (SBS) test. Statistical testing was accomplished using the analysis of variance (P < 0.05). HP-based bleaching gel showed significant differences between measurement intervals in surface roughness, elastic modulus, and SBS parameters (P < 0.05). In contrast, HP-free bleaching gel showed insignificant differences within the group (P > 0.05). The SBS between dentin-composite was significantly affected with the use of HP-based bleaching gel, while HP-free bleaching gel showed insignificant difference between measurement intervals. The qualitative validation of the treatment's impact was further demonstrated using the scanning electron microscopy. The findings suggest that the bonding stability of composite restorations to dentin may be compromised after bleaching with an HP-based gel, whereas immediate bonding procedures can be safely conducted following the application of an HP-free bleaching gel.

Modeling, Calculation and Realization of Au/Nb2O5 Substrates for Surface Plasmon Resonance Sensors

Introduction. Sensor devices based on the surface plasmon resonance (SRP) phenomenon are widely used among the tools of information and diagnostic technologies. The main part of a device based on the surface plasmon resonance phenomenon is a sensor substrate, which consists of a glass plate, a film of plasma-supporting metal, usually gold, and additional layers to increase the sensitivity of the research. Depending on the thickness of the additional dielectric layers, the following types of sensors can be implemented: a conventional SPR sensor with a gold film without a dielectric; an Au/dielectric SPR sensor with a dielectric thickness less than the critical one, in which the system can maintain the plasmonic mode; a waveguide sensor on a metal sublayer, with a dielectric thickness sufficient for the emergence of waveguide modes. The Au/Nb2O5 thin-film system is promising for creating sensor substrates due to the high refractive index of Nb2O5 and its exceptional chemical and mechanical resistance. The purpose of the work. This work is devoted to computer modelling, calculation of performance characteristics and implementation of Au/Nb2O5 sensor substrates for SPR devices, including the Plasmontest series devices developed at the Institute of Cybernetics of the National Academy of Sciences of Ukraine. The behaviour of the characteristics of the SPR substrates with a plasma-supporting gold film, SPR substrates with sensitivity enhancement by an additional layer of Nb2O5 of nanometre thickness and with a waveguide layer of Nb2O5 thickness more than 150 nm are analysed. Calculations were performed for both refractive sensors on SPR and biosensors. Results. The theoretical analysis was carried out by computer modelling in Winspall and calculations in MATLAB using the Fresnel equations and the matrix method, which allowed a comprehensive analysis of the shape of the reflection curves, angular sensitivity, resolution and angular ranges for sensors with different dielectric coatings. It is shown that at a thickness of 0-10 nm, the Au/Nb2O5 structure will work as a SPR sensor with increased sensitivity, and at a thickness of 150-210 nm as a waveguide sensor on a metal sublayer. But, as calculations have shown, only the Au/Nb2O5 SPR sensor is promising for practical implementation to increase the sensitivity of biosensor measurements. The work carried out on the development of thin-film technology, which includes vacuum deposition of a thin-film structure of adhesive Nb (1–2 nm), plasma-supported Au (50 nm), Nb (3–5 nm) and thermal annealing (to oxidise the top layer of niobium), made it possible to implement Au/Nb2O5 substrates for SPR studies. Experimental studies have shown that the angular sensitivity of the Au/Nb2O5 refractometric SPR sensor is 1.5 times higher than that of a SPR sensor with a single Au film at niobium oxide layer thickness of about 6 nm. Thus, the experimentally determined increase in the angular sensitivity of the Au-Nb2O5 SPR sensor is consistent with the theoretical data. Conclusions. Calculations have shown an increase in the angular sensitivity of SPR sensors for Au/Nb2O5 sensor substrates compared to conventional Au film substrates for both refractometric (1.6 times) and biosensor (1.8 times) studies. The sensors on Au/Nb2O5 substrates for SPR studies, which we have designed and practically implemented, are cheap to manufacture, have higher sensitivity, and due to the exceptional chemical and mechanical stability of Nb2O5, can be used repeatedly in rather aggressive environments. Keywords: computer modelling, surface plasmon resonance, sensor, refractometer, biosensor.

High permeance of polyamide nanofiltration membranes with porous organic polymers interlayers based on diazo coupling reaction

Nanofiltration (NF) membranes are widely used in many fields, including food, petrochemical and brackish water desalination. One of the challenges for preparing NF membranes is to make NF membranes with high both permeability and selectivity because of the “trade-off" effect. To weaken or break through the “trade-off" effect, the thin film composite (TFC) NF membranes with high permeability and selectivity were prepared by constructing porous organic polymers (POPs) interlayers via diazo coupling reaction in the wild condition. The effects of the monomers ratio used to prepare POPs interlayers on the separation performance of the as-prepared TFC NF membranes as well as on the surface characteristics of substrate and polyamide (PA) separation layer were investigated. Due to hydrogen bonding, the POPs interlayers with hydroxyl groups slow down the diffusion rate of PIP molecules, which changes the surface structure of the polyamide (PA) separation layer from the nodular structure to the folded structure that favors increased permeability. The pure water permeance of the optimal TFC-S4 membrane (47.5 ± 0.3 L m−2 h−1 bar−1) is 3.8 times higher than that of the commercial polyamide nanofiltration membrane NF270 (12.5 L m−2 h−1 bar−1). Na2SO4 rejection of the TFC-S4 membrane is 98.7 ± 0.1 %, which is greater than that of NF270 (96 %). This study provides ideas for future applications of POPs materials in NF membranes desalination.

Diagnostic investigation of the wall paints conservative state in a hypogeal room of the archaeological park of Baia (Italy)

The present study investigated the correlation between the degradation processes of cultural heritage and the environmental parameters of the semi-confined site that houses it. The latter is a semi-underground room (nymphaeum) found in the Archaeological Park of Baia (Italy) dating back to the third century; it is decorated with marine motifs and painted with frescos techniques from the same period. Relative humidity and temperature were hourly registered, and the collected data were used to derive daily and annual profiles. The effects of microclimate induced degradation were investigated employing various techniques, such as Ion Chromatography for the chemical characterisation of deposits, and Thermography, for the individuation of biological layers. The data obtained showed that the underground environment, partially submerged by rising brackish water, was affected by the presence of biodeteriogens, whose distribution and growth is strongly favoured, above all, by the environmental parameters and by the substrate characteristics. All the data were then cross-referenced to obtain a complete knowledge of the conservation frameworks of the environments, essential to identify the most compatible and effective restoration methodologies to be applied in the conservation of the nymphaeum.

Radiation model and thermal characteristics of OLED glass substrate using electric heating tube

Glass substrate (GS) heating is a fundamental but significant technology for organic light emitting diode (OLED), which is critical to OLED displaying quality and efficiency. A rapid and reliable theoretical model is intensely demanded to guide practical system design, simulation analysis and experimental research for GS heating, but present radiative models are improper or inconvenient. Therefore, this paper establishes a new and direct calculation model with the addition of correctional coefficient 0.5 to blackbody radiation power of electric heating tube (EHT) and the proposal of comprehensive angle coefficient X, which can solve single and multi-source radiation problems theoretically. The simulation and experiment are both conducted for comparison analysis. The temperature errors of theory and simulation for multi EHTs are all within 1 % when compared with experimental results, which well validates the reliability and accuracy of theoretical and simulation models. Large EHT radius r, small distance L between EHT and GS, and suitable EHT number n are suggested, which benefits to the improvement of radiation heating and temperature uniformity of GS. It is hoped that this study can provide a useful tool on thermal radiation analysis and also a valuable promotion for practical OLED heating technology.

Memristive gas sensor (gasistor) based on Ag/ordered TiO2 nanorods/FTO sandwich structure for evaluation of ethanol concentration in mixed ambient

Herein, we designed a memoristor-type gas sensor (gasistor) with Ag/ordered TiO2 nanorods/FTO sandwich structure for recognizing ethanol concentration in ethanol-methanol mixtures. The gas adsorption characteristics of different TiO2 substrates were first investigated by first-principle calculations. The results showed that the TiO2 surface in the low resistance state exhibited better immunity to other interfering gas molecules. However, similar adsorption energies and charge transfers calculated for adsorption of methanol and ethanol mean that the interference of methanol to the response of ethanol cannot be completely ignored. In next experiments, the Ag/TiO2/FTO gasistor with well-aligned TiO2 nanorods as the resistive layer was constructed successfully and demonstrated the stable resistive switching function and excellent retention characteristic. Further device tests confirm the ability of the gasistor in the low resistance state to discriminate between ethanol and methanol, as well as better anti-interference for other organic vapors. Also, an ultra-short recovery time (∼1.8 s) was observed by applying a direct current scanning voltage to the gasistor. Finally, to improve the recognition rate of ethanol in ethanol-methanol mixed atmosphere, a neural network algorithm based on back-propagation was incorporated and good prediction accuracy was obtained at ethanol concentrations ≥ 5 ppm.

Recent Advances of the Ultimate Microbial Influenced Corrosion (MIC): A Review

Abstract: The persistent corrosion of metal surfaces poses a significant engineering challenge, including material degradation, loss of metal-structural integrity, and massive maintenance costs in various industrial, medical, and aerospace applications. Microorganisms such as archaea, bacteria, fungi, and microalgae can directly or indirectly influence metal corrosion. The degree of corrosiveness and corrosion healing varies depending on the microbe, medium, and metal substrate characteristics. Several attempts have been made to reveal answers to all questions about MIC. The published reports focused on testimonial failures and laboratory or field tests under varied situations. This review offers an overview of the most recent MIC research and emphasizes the scarcity of data on MIC detection, estimation, and the most recent approaches for MIC management. The review extends previously reported works and summarizes efforts for better understanding and cutting off MIC management in advanced technologies. Furthermore, it concludes with a final discussion of the current and future drawbacks and protective systems for preventing microbial-induced corrosion.

Deeper insight into the storage time of food waste on black soldier fly larvae growth and nutritive value: Interactions of substrate and gut microorganisms

Biological treatment of food waste (FW) by black soldier fly larvae (BSFL) is considered as an effective management strategy. The composition and concentrations of nutrients in FW change during its storage and transport period, which potentially affect the FW conversion and BSFL growth. The present study systematically investigated the effect of different storage times (i.e., 0–15 d) on FW characteristics and its substantial influence on the BSFL growth. Results showed that the highest larvae weight of 282 mg and the shortest growth time of 14 days were achieved at the group of FW stored for 15 days, but shorter storage time (i.e., 2–7 d) had adverse effect on BSFL growth. Short storage time (i.e., 2–4 d) improved protein content of BSFL biomass and prolonged storage time (i.e., 7–10 d) led to the accumulation of fat content. The changes of substrate characteristics and indigenous microorganisms via FW storage time were the main reasons for BSFL growth difference. Lactic acid (LA) accumulation (i.e., 19.84 g/L) in FW storage for 7 days significantly limited the BSFL growth, leading to lowest larvae weight. Both the substrate and BSFL gut contained same bacterial communities (e.g., Klebsiella and Proteus), which exhibited similar change trend with the prolonged storage time. The transfer of Clostridioides from substrate to BSFL gut promoted nutrients digestion and intestinal flora balance with the FW stored for 15 days. Pathogens (e.g., Acinetobacter) in BSFL gut feeding with FW storage time of 7 days led to the decreased digestive function, consistent with the lowest larvae weight. Overall, shorter storage time (i.e., 2–7 d) inhibited the BSFL digestive function and growth performance, while the balance of the substrate nutrients and intestinal flora promoted the BSFL growth when using the FW stored for 15 days.

An algal regulation-based molasses vinasse anaerobic digestion strategy for enhancing organic matter removal and methane production

Microalgae are suitable type of anaerobic co-digestion (AcoD) substrate that can effectively alleviate microbial inhibition caused by substrate characteristics (molasses vinasse, MV). Therefore, our investigated the synergistic effects, organic matter removal, and potential microbiological impacts in the AcoD of MV and Desmodesmus opoliensis strain GXU-A4. We conducted batch AcoD using simple dehydrated GXU-A4 (Fresh D. opoliensis, FDO) and lipid-extracted GXU-A4 (Pretreated D. opoliensis, PDO). The highest methane potential of PDO biomass was 124.9 ± 0.8 mL g−1 VS, while AcoD with MV increased methane production by 11 % and promoted acetic acid production. FDO biomass reduced nitrogen-containing organic matter and humic-like production. Microbial community and functional prediction analyses revealed that AcoD altered the distribution of hydrolytic acidogenic bacteria, such as Bacteroidetes and Cloacimonadota (W5). Our study provide a new insight into the control strategy of AcoD for methane production, removal of organic matter, and microbial mechanisms in algae biomass.

Biochar Amendment in Green Roof Substrate: A Comprehensive Review of the Benefits, Performance, and Challenges

Green roofs (GRs) are a well-established green infrastructure (GI) strategy that have been extensively studied for decades to address a growing array of social and environmental challenges. Research efforts have been continuously made to contribute to the awareness of benefits of GRs and towards their widespread application. The substrate, which is one of the crucial layers of a GR system, plays a major role in the serviceability of GRs. Thus, several studies have been undertaken to alter the substrate characteristics by applying innovative substrate additives. Biochar, a carbon-rich material with a highly porous structure and large specific surface area, has been found advantageous in several areas such as agriculture, water filtration, environmental remediation, construction, and so on. However, the application of biochar in GRs has been insufficiently studied, partially because biochar amendment in GRs is a relatively recent innovation. Furthermore, a comprehensive review of the performance of biochar-amended GR substrates is lacking. This review paper aims to summarize the past performance of GRs enhanced with biochar by considering the various benefits that biochar offers. The results indicate that most of the reviewed studies observed increased retention of runoff and nutrients when utilizing biochar. Additionally, the capabilities of biochar in improving thermal insulation, plant performance, and microbial diversity, as well as its effectiveness in sequestrating carbon and controlling soil erosion, were mostly agreed upon. Notwithstanding, a definitive conclusion cannot yet be confidently made due to the limited research information from biochar–GR systems and the uneven research focus observed in the studies reviewed. The influence of biochar-related variables (including amendment rates, application methods, processed forms, and particle size) on the effectiveness of biochar was also discussed. Opportunities for future research were suggested to fill the research gaps and address challenges restricting the application of biochar in GRs. Detailed information from past research findings could serve as a foundation for further investigations into the large-scale implementation of biochar in GRs.

Characterization of Very Thin 3C-SiC Epilayers on Si

We verify experimentally to what extent the intensity of 3C-SiC TO peak in infrared reflectance spectrum can be used to estimate the thickness of extremely thin 3C-SiC epilayers on Si. The influence of several Si substrate characteristics (orientation, doping level, back-side surface preparation) on the peak calibration is discussed.

Enhancing Biogas Production: An Assessment of Pasteurization Effects on Poultry, Swine, Bovine Manure and Food Waste Substrates

Within the evolving regulatory landscape of the European Union concerning animal by-product (ABP) management within the circular economy framework, this study explores the concurrent objectives of safeguarding public health and environmental integrity and maximizing final product value. Anaerobic digestion (AD) emerges as a holistic solution for ABP management, addressing sanitation concerns while enhancing end-product quality. Through laboratory-scale experimentation, the AD process applied to four substrates—poultry manure, swine manure, cattle manure, and food waste—is scrutinized. Prior to AD, pasteurization at 70 °C for 60 min ensures microbial safety. Subsequently, four experimental AD cycles compare pasteurized and unpasteurized substrates. Results highlight the efficacy of pasteurization in sanitizing final products across all substrates, emphasizing its pivotal role in product safety. However, pasteurization’s impact on system performance varies. While enhancing biogas yield from animal waste notably, its influence on food waste biogas production is less pronounced, indicating substrate-specific dynamics. This study offers insights into optimizing ABP management strategies, emphasizing the interplay between pasteurization, substrate characteristics, and AD performance. Such insights are crucial for advancing sustainable practices in the circular economy paradigm, balancing environmental stewardship with economic viability.

Non-composted and blended agro-industrial by-products an as alternative soilless substrate affect potted zonal geranium (Pelargonium x hortorum) and murva (Murraya paniculata) production

Due to their hiking prices and import restrictions, peat moss and coco coir are not readily available in many developing countries including Pakistan. Therefore, it is necessary to explore alternative soilless substrates having low cost and comparable physico-chemical properties with peat moss and coco coir for local and global market. For this purpose, indigenous agro-industrial by-products, viz., sesame straw, date palm coir, sugarcane pressmud, sugar beet waste and pine bark were collected, cleaned, crushed (where needed) and blended for physico-chemical analyses. Zonal geranium ‘Pinto White’ and murva (Murraya paniculata Kaneh.) were used to evaluate the efficacy of various combinations of substrates on plant growth and production. Three experiments were conducted with six treatments of each experiment replicated three times. Blending of sesame straw with sugarcane pressmud and pine bark (4:4:2 by volume) yielded best results and marketable plants were produced with tallest height (35.8 cm), canopy diameter (20.8 cm), leaf area (29.2 cm2), leaf total chlorophyll contents (62.1 SPAD) and flowers per plant (5.0 No.) along with shortest production time (103 days). Same results were recorded when murva plants were grown in 4:4:2 blending of sesame straw, sugarcane pressmud and pine bark. Zonal geranium and murva plants did not perform well when sesame straw was blended with date palm coir and sugar beet waste. Blending of sesame straw with sugarcane pressmud and pine bark had low pH (7.0), electrical conductivity (1.37 mS cm-1), bulk density (0.29 g cm-3) while high water retention (34.7 %) as compared to other blended substrates. However, shrinkage of substrates in containers was highest (7.7 %) when sesame straw was blended with sugarcane pressmud and pine bark in 5:3:2 followed by 4:4:2. pH value of all blended substrates decreased at termination except when sesame straw, sugarcane pressmud and pine bark were blended in 4:4:2 and 5:2:3, which was increased from 7.0 to 7.1. Electrical conductivity of all blended substrates was decreased at termination of the experiments. It can be concluded that blending of sesame straw, sugarcane pressmud and pine bark in 4:4:2 (v/v/v) significantly improved physico-chemical characteristics of substrates as well as plant growth and production attributes of zonal geranium and murva. Therefore, this indigenous soilless substrate, which is cheaper and readily available to nurserymen can be used as alternative of peat moss and coco coir for containerized plant production.

Catalytic Activity of Incorporated Palladium Nanoparticles on Recycled Carbon Black from Scrap Tires.

A stable support substrate for catalytically active metal nanoparticles (NPs) plays an important role in various chemical transformation reactions. This study describes the effective integration of catalytically active palladium nanoparticles (PdNPs) into recycled carbon black (rCB) obtained from scrap tires. The loading efficiency and dispersion degree of PdNPs prepared via a deposition-precipitation method are thoroughly compared to those prepared with conventional Vulcan CB. As the rCB powder exhibits relatively larger surface areas and wider pore size distributions, slightly polydisperse and more PdNPs are integrated across rCB than those on CB. These composite materials are subsequently tested as catalysts in the Suzuki coupling and styrene hydrogenation reactions. For the Suzuki reaction using phenylboronic acid and bromobenzene, the PdNPs on rCB exhibit slightly higher reactivity than those on CB (TOF of ∼9/h vs ∼8/h), presumably due to the structural features of the integrated PdNPs and the relatively hydrophobic characteristics of the rCB substrate. For the hydrogenation reaction, both composite materials easily result in over 99% yield under ambient conditions with similar activation energies of ∼32 kcal/mol. These composite materials are also recyclable in both reactions without a detectable loss of the PdNP catalyst and its activity. Understanding the physicochemical properties of rCB and demonstrating their potential use as a catalyst support substrate evidently suggest the possibility of replacing conventional CB, which also provides an idea of upcycling waste tires in the development of practical and green reaction systems.

The Role of Oxygen on Defects Formation during Advanced Silicon Process Technologies

Impact of oxygen in silicon substrates and the formation of oxide precipitates have been widely studied in the past because of the detrimental electrical recombination and its effect on yield [1,2]. The origin of interstitial oxygen (Oi) is not only limited to the substrate but also comes from the nature of the oxide that may be deposited on it [3]. Interstitial oxygen plays a direct role in the formation of bulk microdefects (BMDs) resulting from oxygen precipitation during low-temperature Front-End anneals at 650-800°C [4,5]. The latter are of interest for the mechanical robustness of substrates, contributing to the pinning of slip lines (SL) and for the reliability of devices thanks to an internal gettering effect, but can also be harmful by emitting dislocations when they are too numerous (> 1 x 1010 BMD.cm-3) [5, 8].In this paper, we have reviewed the different impacts of interstitial oxygen on silicon substrates during thermal annealing through 3 phenomena: (i) the influence of Oi on the reduction of the slip lines by the pinning effect, (ii) the formation of BMDs induced by Oi and their interactions with dopants during implantation processes, (iii) the BMDs limited formation in the specific case of high resistivity (HR) silicon substrates. We focused on standard and high resistivity silicon substrates obtained by Czochralski (CZ) method, used in advanced technologies for various applications (digital, bipolar, power, photonic, etc.).To highlight the impact of interstitial oxygen, firstly on the mechanical properties of substrates, we studied the same p-type silicon substrates with two ranges of Oi concentration (5.33 x 1017 and 7.23 x 1017 at.cm-3), both annealed by furnace oxidation below 1000°C and N2 annealing above 1000°C. Figure 1 clearly shows the effect of a minor difference in Oi concentration on the number of slip lines detected by Pattern Wafer Geometry (PWG) measurements (Figure 2). Despite extrinsic process parameters to consider in the occurrence of slip lines, these results demonstrate the enhancement of slip line pinning by interstitial oxygen.Bulk microdefects in silicon are known to interact with dopants [6]. To investigate this point, we compared the BMD occurrence in non-implanted and antimony-implanted (2 x 1015 at.cm-2) silicon substrates using micro-photoluminescence imaging. These substrates contain relatively high Oi concentrations (up to 6.7 x 1017 at.cm-3) and have been subjected to oxidation and rapid thermal annealing (RTA) above 900°C. After adjusting for background contrast in the implanted and non-implanted regions, Figure 3 shows different trends in BMD density evolution as a function of the probed depth. We assume that a mechanism based on a mechanical stress field induced by the position of the Sb-implanted atoms in the lattice limits the nucleation of oxide precipitates [7]. However, further characterization methods are required to confirm the influence of dopants on the BMD density.Finally, high resistivity silicon substrates are being considered to significantly improve devices performance, particularly in high frequency and photonics applications [8, 9]. However, the understanding of BMD formation is poorly documented in the literature. These CZ-Si substrates are characterized by low oxygen content (< 3 x 1017 at.cm-3) and low boron dopant concentration (< 1 x 1014 at.cm-3). At such low values, the expected oxygen precipitation is very different from that of standard p-type silicon [8, 10]. We investigated the effect of these parameters on BMD formation through precipitation thermal treatments (N2 + O2 anneal > 1000°C). Figure 4 illustrates the important difference in BMD formation depending on the substrate characteristics (standard resistivity high-Oi versus high resistivity low-Oi silicon) after the same thermal treatment. BMD defects were generated in large quantities in standard silicon (3 x 109 BMD.cm-3), whereas no BMDs were observed in HR silicon.In summary, we have demonstrated the impact of interstitial oxygen (coming from substrates and processes) on defect generation, particularly BMD, in silicon technology. In controlled proportions, they play an important role in the proper functioning of devices and very often result from the fine tuning between substrate characteristics and process conditions.[1] Jun Fujise et al 2018 JJAP. 57 035501[2] Zijing Wang et al 2022 APE 15 071004[3] G. Kissinger et al 2019 ECS J3ST. 8 N79[4] Maria Porrini et al 2018 ECS Trans. 86 7[5] Hirofumi Shimizu et al 1985 JJAP. 24 815[6] Hideki Tsuya et al 1983 JJAP. 22 L1[7] Oleksandr Oberemok et al 2014 PSS. 11 163439[8] Isabelle Bertrand et al 2022 ECS Trans. 31 108[9] Jarosław Judek et al 2017 JEM. 46 5589-5592[10] Kaoru Kajiwara et al 2019 PSS. 17 216 Figure 1