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The fault gouge, a crushed fault rock resulting from seismic slip, exhibits variations in crystallinity and particle size contingent on the magnitude of deformation. Therefore, the fabrication of fault gouge analogues with carefully controlled properties such as crystallinity, grain size, and mineral composition is necessary to systematically study their role in a range of fault slips. While the single mineral fault gouge analogues have been reproduced using a milling method, the fabrication methods for multi-mineralic fault gouge analogues with varying particle size and crystallinity are rarely reported, yet. In this study, we propose two methodologies for fabricating multi-mineralic fault gouges controlling the degree of amorphization and the particle size using a high-energy ball mill: mixing-grinding (MG) and grinding-mixing (GM) types. The MG type was designed to simulate the fault gouge that the same grinding energy is applied to all the constituent minerals, while the GM type can be controlled the degree of deformation of each mineral according to the research objective. To investigate the effects of these methodologies on the reduction in crystallinity and particle size, we compared the characteristics of MG type_6h and GM type_6h samples, both ground for 6 h. Consequently, despite undergoing the same grinding duration, the GM type_6h sample exhibited more significant reduction in crystallinity and more heterogeneous particle size. Additionally, we fabricated the GM type_Xc50 sample, where the crystallinity of all constituent minerals was reduced to < 50%. For this, each mineral was ground for an optimized duration that reduced its crystallinity to < 50%, after which the samples were mixed. Consequently, the GM type_Xc50 sample demonstrated the greatest reduction in crystallinity and the most uniform particle size distribution. To fabricate the generation process of natural fault gouge, it is appropriate to use the MG type to apply the same energy to constituent mineral, resulting the deformation reflecting its hardness. The GM type is recommended for use in fabricating the characteristics of the fault gouge that has undergone intense deformation at the slip surface, which allows for controlling the uniform crystallinity and particle size reduction of each constituent mineral. Our results suggest that the diverse nature of naturally occurring fault gouges can be fabricated in laboratory settings by adjusting the grinding conditions. This study offers effective methods for fabricating fault gouge analogue for frictional experiments for fault slip and potential applications in simulating geochemical reactions in fault zones. [ABSTRACT FROM AUTHOR]

Comminution processes play a pivotal role in diverse applications, ranging from food processing, to mining and materials engineering. The pharmaceutical industry is no exception, with an increased focus on particle engineering to overcome the growing challenges related to the complexity of new drug molecules such as poor water solubility or stability issues. Additionally, the preparation of powders for pulmonary, transdermal, topical, ophthalmic, oral or parenteral administration often requires specific particle size requirements. Thus, milling technologies offer an excellent option for controlling particle size, improving the stability, dissolution, absorption rate, and bioavailability of poorly water-soluble drugs. They also contribute to enhancing pharmaceutical forms and overall product performance. This review highlights the different types of technologies used for comminution, the respective advantages and drawbacks, as well as connected topics including feed material properties, analytical techniques, process analytical technology, process safety, new top-down technologies and key information to consider when selecting a technology. Thus, an in-depth approach of comminution in the pharmaceutical industry is presented. This compilation serves as a source of comprehensive information for those who decide to initiate research projects in this field, or to update their existing literature knowledge and understanding. [ABSTRACT FROM AUTHOR]

Aqueous suspensions containing crystalline drug in the sub-micron range is a favorable platform for long-acting injectables where particle size can be used to obtain a desired plasma-concentration profile. Stabilizers are added to the suspensions and screened extensively to define the optimal formulation composition. In the initial formulation screening the amount of drug compound can be limited, necessitating milling methods for small-volume screening predictable for scale-up. Hence, adaptive focused ultrasound was investigated as a potential milling method for rapid small-volume suspensions by identifying the critical process parameters during preparation. Suspensions containing drug compounds with different mechanical properties and thereby grindability, i.e., cinnarizine, haloperidol, and indomethacin with brittle, elastic, and plastic properties, respectively, were investigated to gain an understanding of the manufacturing with adaptive focused acoustics as well as comparison to already established milling techniques. Using a DoE-design, peak incident power was identified as the most crucial process parameter impacting the milling process for all three compounds. It was possible to decrease the sizes of drug particles to micron range after one minute of focused ultrasound exposure which was superior compared to other milling techniques (e.g., non-focused ultrasound exposure). The addition of milling beads decreased the drug particle sizes even further, thus to a lower degree than other already established milling techniques such as milling by dual centrifugation. This study thereby demonstrated that adaptive focused ultrasonication was a promising method for rapid homogenization and particle size reduction to micron range for different compounds varying in grindability without altering the crystalline structure. [ABSTRACT FROM AUTHOR]

Particle size reduction by ultrasound is more favorable than conventional grinding due to its tendency to preserve the material's crystal structure. For palygorskite clay, the optimization was carried out using response surface methodology for the variables of sonication time, power, duty cycle, and clay loading. A 2FI model was fit to the dimensionless size number to navigate the design space of the model with an r-squared value of 0.9662. We found that the most optimal conditions for the size reduction were 45 min of sonication time, 110 W of sonication power, 90% duty cycle and 0.06 g/mL of clay loading. The loading and duty cycle terms had a positive effect on the particle size reduction, while an increase in power increased the particle size of the clay. The effect of time was found to be dependent on the values of the clay loading as well as the duty cycle. The XRD analysis of palygorskite clay for the untreated and treated samples indicated that ultrasound causes minimal changes to the crystal structure of the clay. The overall outcome of the study suggests that at optimal ultrasound conditions, particle size is reduced to ~ 1/16 times the initial value and the electric power input in the ultrasound generator takes an energy requirement of ~ 0.0124 kWh/g of solids processed for size reduction. [ABSTRACT FROM AUTHOR]

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One challenge in the development of new drug formulations is overcoming their low solubility in relevant aqueous media. Reducing the particle size of drug powders to a few hundred nanometers is a well‐known method that leads to an increase in solubility due to an elevated total surface area. However, state‐of‐the‐art comminution techniques like cryo‐milling suffer from degradation and contamination of the drugs, particularly when sub‐micrometer diameters are aspired that require long processing times. In this work, picosecond‐pulsed laser fragmentation in liquids (LFL) of dispersed drug particles in a liquid‐jet passage reactor is used as a wear‐free comminution technique using the hydrophobic oral model drugs naproxen, prednisolone, ketoconazole, and megestrol acetate. Particle size and morphology of the drug particles are characterized using scanning electron microscopy (SEM) and changes in particle size distributions upon irradiation are quantified using an analytical centrifuge. The findings highlight the superior fragmentation efficiency of the liquid‐jet passage reactor setup, with a 100 times higher fraction of submicrometer particles (SMP) of the drugs compared to the batch control, which enhances solubility and goes along with minimal chemical degradation (<1%), determined by attenuated total reflection‐Fourier transform infrared spectroscopy (ATR‐FTIR), high‐performance liquid chromatography (HPLC), and X‐ray diffraction (XRD). Moreover, the underlying predominantly photo‐mechanically induced laser fragmentation mechanisms of organic microparticles (MP) are discussed. [ABSTRACT FROM AUTHOR]

Since the caecal microbiota of young broilers are not yet able to ferment the dietary fibre (DF) fraction of the feed to a large extent, increasing the accessibility of DF substrates along the gastrointestinal tract is crucial to benefit from the health stimulating metabolic end-products (e.g. butyric acid) generated upon microbial DF fermentation. Therefore, the present study aimed to evaluate the potential of reduced-particle size wheat bran (RPS-WB) and endoxylanases as feed additives to stimulate arabinoxylan (AX) hydrolysis and fermentation along the hindgut of young broilers. To this end, RPS-WB and endoxylanase supplementation were evaluated in a 2 × 2 factorial design using a total of 256 male 1-d-old chicks (Ross 308). Broilers were assigned to 4 dietary treatments: a basal wheat-based diet with (1) no feed additives (control, CTRL), (2) an endoxylanase (XYL; Econase XT 25 at 0.10 g/kg diet), (3) 1% wheat bran with an average reduced particle size of 297 μm (RPS-WB) and (4) an endoxylanase and 1% RPS-WB (RPS-WB + XYL). Each dietary treatment was replicated 8 times and on d 10 and 28, respectively, 24 and 16 broilers per treatment group were euthanised to analyse AX degradation, short-chain fatty acid production and digesta viscosity in the ileum and caecum. Broilers receiving XYL in their diet showed increased AX solubilisation and fermentation at both d 10 and 28 compared to the CTRL group (P

The low oral bioavailability of active pharmaceutical ingredients in aqueous media causes to partial absorption through the gastrointestinal tract. Increasing surface area by particle size reduction has been accomplished to overcome these challenges. In this study, Aprepitant (APT) nanoparticles were prepared using a green solvent anti-solvent precipitation method based on subcritical water (SW) technology. Effects of three different parameters such as SW temperature (368.15–388.15 K), anti-solvent temperature (273.15–293.15 K), and polyethylene glycol concentration (0.02–0.04 wt%) were studied on the size and morphology of the produced nanoparticles. As the next step, optimization of the process was performed using the response surface Box-Behnken design (BBD), and optimum operational conditions were obtained as follows: SW temperature (388.15 K), anti-solvent temperature (283.15 K), and polyethylene glycol concentration (0.04 wt%). The results revealed a significant decline in the size of the precipitated particle by subcritical water-based technologies (5.0 nm, on average), as compared to the unprocessed drug particles (30 μm, on average). Green SW-based technologies are proposed for the preparation of APT nanoparticles with no requirement for organic solvents and post-processing purification stages. [Display omitted] • Drug original particles were nanosized using subcritical water anti-solvent technology, for the first time. • Influences of solvent temperature, anti-solvent temperature and PEG concentration were investigated. • Optimization of the process was performed using the response surface Box-Behnken design (BBD). • Mean particle size of aprepitant has been reduced from its original 30 μm to 5 nm. [ABSTRACT FROM AUTHOR]

Fault gouge, located in highly deformed fault cores, shows substantial particle size reduction and loss of crystallinity, which could affect the physicochemical properties and thus control the slip behavior and earthquake stability of a fault. To systematically investigate the effect of deformed fault gouge on fault slip behavior in laboratory-scale experiments, a fault gouge analog with variable particle size and crystallinity is required. However, the systematic study for formation of a fault gouge analog (i.e., controlling the particle size and crystallinity) was not performed well. In this study, we investigated the effect of the rotation speed of a high-energy ball mill on particle size reduction rate and degree of amorphization. As the rotation speed increased from 500 to 2000 rpm, the comminution rate linearly increased, and reached a reduced particle size limit. The degree of amorphization and its rate also increased with increasing rotation speed. Upon grinding, the X-ray diffraction (XRD) peaks markedly decreased and reached critical amorphization points within 120 min, except for the case of grinding with a rotation speed of 500 rpm. Talc ground with a rotation speed of 500 rpm did not reach steady-state in mechanical amorphization after 360 min of grinding, thus necessitating prolonged grinding for further amorphization. A comparison of talc powders having similar specific surface areas, but ground at different rotation speeds, shows that grinding with a higher rotation speed for a shorter duration preserves the crystalline structure relatively well compared with grinding at a lower rotation speed for a longer duration. These results indicate that optimizing the grinding rotation speed facilitates the formation of talc fault gouge analogs with systematically varying particle size and crystallinity. The specific surface area of talc increased from 6.1 to 365 m2/g, and the degree of crystallinity decreased from approximately 75% to 11%. Our results indicate that an artificial talc fault gouge can be prepared by varying the particle size and crystallinity using a high-energy ball mill. [ABSTRACT FROM AUTHOR]

Poly (ethylene-co-vinyl acetate) (PEVAc) is a copolymer endowed with high elasticity and resilient properties, potentially utilized in various applications. However, the tensile strength of this copolymer is insufficient for use in certain applications that require enough strength to tolerate high external tension or stress. In this study, dolomite was proposed as a nanofiller to reinforce the PEVAc. Raw dolomite was physically and chemically modified in order to improve its mix ability and interfacial adhesion between the PEVAc and dolomite. Initially, the size of dolomite was reduced by combining the ball-milling and tip-sonication methods. SEM, TEM, and XRD were used to characterize the morphology/structure of the raw dolomite and the size-reduced dolomite. Then, a particle size analysis was performed to confirm the average particle size. Our results show that the particle size of dolomite was reduced from 150 µm to 441.4 nm by the physical modification process (size reduction). Based on the TEM analysis, the Feret diameter (df) of the dolomite particles was also reduced from ~112.78 µm to ~139.58 nm only. This physically modified dolomite is referred as dolomite nanoparticles (DNPs), since one or more of its dimensions is less than 100 nm (e.g., thickness and width). To further improve the dolomite and PEVAc matrix interactions, chemical modification of the DNPs were performed by treating the DNPs with stearic acid, forming non-polar dolomite nanoparticles (NP-DNPs). The presence of stearic acid in dolomite was confirmed through FTIR and contact angle analyses. A PEVAc nanocomposite film with NP-NPDs as a nanofiller appeared more homogeneous and exhibited the highest increment in tensile strength and elongation at break. These findings indicated that the combination of ball milling and tip sonication is an efficient method for producing very fine dolomite particles up to the nano-size range, whereas chemical surface modifications improved the compatibility between the dolomite and the copolymer. The combination of these physical and chemical modifications helped to develop a homogeneous copolymer nanocomposite system with improved tensile properties. [ABSTRACT FROM AUTHOR]

Implant-associated infection due to biofilm formation is a growing problem. Given that silver nanoparticles (Ag-NPs) have shown antibacterial effects, our goal is to study their effect against multispecies biofilm involved in the development of peri-implantitis. To this purpose, Ag-NPs were synthesized by laser ablation in de-ionized water using two different lasers, leading to the production of colloidal suspensions. Subsequently, part of each suspension was subjected to irradiation one and three times with the same laser source with which it was obtained. Ag-NPs were immobilized on the surface of titanium discs and the resultant materials were compared with unmodified titanium coupons. Nanoparticles were physico-chemically analysed to determine their shape, crystallinity, chemical composition, and mean diameter. The materials were incubated for 90 min or 48 h, to evaluate bacterial adhesion or biofilm formation respectively with Staphylococcus aureus or oral mixed bacterial flora composed of Streptococcus oralis, Actinomyces naeslundii, Veionella dispar, and Porphyromonas gingivalis. Ag-NPs help prevent the formation of biofilms both by S. aureus and by mixed oral bacterial flora. Nanoparticles re-irradiated three times showed the biggest antimicrobial effects. Modifying dental implants in this way could prevent the development of peri-implantitis. [ABSTRACT FROM AUTHOR]

In recent years, significant academic and commercial interest has focused on collagen derived from horse tendons, with potential applications across diverse sectors such as medicine, pharmaceuticals, and cosmetics. Nano collagen, with its enhanced wound penetration, improved cell contact, and heightened cellular regeneration and repair capabilities due to its high surface area, holds promise for a wide range of applications. In this study, we present a novel method for producing nano collagen from the equine tendon. Our approach is characterized by its speed, affordability, simplicity and environmentally friendly nature, with precise temperature - control to prevent collagen denaturation. We conducted a comprehensive characterization of the obtained samples, including assessments of morphology, chemical and thermal properties, particle size distribution and biocompatibility. Importantly, our results indicate improvements in thermal stability, and surface roughness of nano collagen, while preserving its molecular weight. These advancements expand the potential applications of nano collagen in various fields. [Display omitted] • Swift, cheap and environmentally conscious nano-sized collagen by ball milling • Effect of the mechanical treatment on the microstructure, size and thermal stability • Improvement in thermal stability and surface roughness of nano collagen • Increase of collagen application range guaranteed by the nanometric size [ABSTRACT FROM AUTHOR]

[Display omitted] • VBSS contains above 40% CaO which poses difficulty in recovering vanadium, hence parametric ball-milling was used. • Above 80% vanadium was effectively recovered with the low-temperature Na 2 CO 3(aq) MA-Leaching. • The MA parametric modeling integrated the chemical concentration into derivation for effective reactivity prediction. • The process is simple, low-temperature leaching, cost-effective, and eco-friendly. Powder formation using a ball mill has found applications in various industries such as extractive metallurgy, nanomaterials, chemicals, materials science, and pharmaceuticals, but the particle size reduction rate, speed, and milling/ignition time required for each industrial application are very crucial. A novel environmentally-friendly parametric modeling of wet ball-milling- Na 2 CO 3 (aq) leaching at low temperature without roasting operation was carried out to recover vanadium from vanadium-bearing steel slag (VBSS). The paradigm shift in the source of strategic metals (SMs) globally validates the fact that the gangue of today is the valuable mineral of tomorrow. Due to the depletion of primary resources, the world has shifted focus towards recovering SMs from secondary resources to cater to its upsurge demands and sustainability worldwide satisfactorily. VBSS has proven to be a promising secondary resource from which SMs especially vanadium can be recovered more economically and environmentally via mechanical activation-assisted leaching. In previous research works, a rigorous process (high temperature, high stirring speed pressure MA- leaching with/without roasting) has been used to recover vanadium from VBSS. This present research work investigated the effective processing of VBSS by paying meticulous attention to the processing parameters via particle size reduction (reactivity) equation derivation considering the chemical solution. A vanadium recovery efficiency above 80 % was achieved from VBSS at a reaction/milling time of 30 min, ball size 10 mm, BPR 7.8, speed 140 rpm, leaching time 2hrs, leaching temperature 80 °C–90 °C, and stirring speed 300 rpm. Generally, the experimental and derived theoretical model results follow the same trend in perfect agreement. [ABSTRACT FROM AUTHOR]

In pharmaceutical research and development, various new chemical entities (NCE) are found to be poorly water-soluble. Therefore, solubility enhancement, a key factor for higher bioavailability, is a major challenge in pharmaceutical industries. Particle size reduction is one such method that increases the surface area of the pharmaceutical compounds and subsequently leads to a higher dissolution rate and bioavailability. Conventional processes such as milling, high-pressure homogenization, and spray drying are well established and widely used for particle size reduction. However, a few disadvantages such as a broader particle size distribution (PSD) and thermal and chemical degradation of the product are major concerns for the product quality. Non-conventional processes such as liquid anti-solvent crystallization, supercritical anti-solvent process, rapid expansion of supercritical solutions, particles from gas saturated solutions, and pulsed laser ablation are emerging as potential alternatives to overcome the disadvantages of conventional processes. This review critically summarizes the milling, spray drying, high-pressure homogenization, liquid anti-solvent crystallization, spray freeze-drying, supercritical carbon dioxide (SC C O 2) –based micronization processes, pulsed laser ablation and combinative techniques. The success of these processes in enhancing the dissolution rate and bioavailability of many active pharmaceutical ingredients (APIs) has been critically examined. The advantages and limitations of these processes are also discussed. Finally, opportunities for future research are also proposed. [ABSTRACT FROM AUTHOR]

A conical screen mill is commonly used to reduce particle size and produce granules of the required particle size. In the present work, an experimental study was designed to explore the use of a comil for the milling of soft solids. As a helpful example for research on soft solids, soap noodles were selected for optimizing the milling parameters such as impeller speed and type, screen type and size, and design of the milling cycle. A preferable combination of the comil parameters was the one generating a minuscule percentage of fines as also the one causing no damage or softening of the structure whatsoever due to agitation or temperature. The study involves comparing the particle sizes statistically and computing different parameters for designing the process. The particle size distribution of the soap granules obtained from the comil affects the soap bar's hardness and friability when punched. Hence, it was deduced that, for soft solids like soap noodles, comil can be helpful in particle size reduction, provided the parameters are optimized according to the mechanical properties of the material. Finally, this work presents a novel application to the comil equipment and gives a new processing technique for soap noodles.

The contribution of ultrasound-aided particle size reduction to the efficiency of the subsequent enzymatic hydrolysis and the accompanying morphological changes of bleached cotton and linen powders were investigated. The aqueous suspensions of cellulosic powders were pretreated either with an ultrasonic bath (US-B) or with a horn-type reactor (US-H). Results revealed that the impact of US-H was more pronounced than that of the US-B. Clearly, the linen particles were more sensitive to ultrasonication than cotton. The US-H modified the particle size distribution differently for the cotton and linen powders and reduced the mean size of particles from 49 to 40 µm and from 123 to 63 µm, respectively. A significant increase in the water retention and water sorption capacity was also measured. The smaller particles with increased accessibility were preferably digested in the enzyme treatment, resulting in a considerably higher concentration of reducing sugars and an enrichment of the residual particles with a larger average size (cotton: 47 µm; linen: 66 µm).

Background: The application of natural products in dentistry has been widely explored. Anchovy (Stolephorus in Latin) has been examined for its bioactive content (calcium, phosphorus and fluoride) as an agent for bone stimulation and tooth development, topical fluoridation and pulp capping. Ball milling has been used to prepare calcium oxide nanoparticles from snakehead fish bone., Objectives: The aim of the study was to reduce the particle size of Stolephorus sp. powder to the nanoscale using high-energy ball milling for 8, 12 and 24 h, and to analyze the optimal milling time by comparing the powder characteristics., Material and Methods: The Stolephorus sp. were oven-dried at 50°C for 6 h, after which the entire fish were crushed into powder. The fish powder was produced by blending the material for 5 min and passing it through a 200-mesh sieve. The remaining dried fish was blended again for 5 min until it passed through the sieve. The top-down approach to the particle size reduction was performed using high-energy milling at 3 distinct time points (8, 12 and 24 h). The characteristics of the powder were evaluated using a particle size analyzer, a Fourier-transform infrared spectrometer (FTIR) and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS)., Results: The Stolephorus sp. powder contained 64.50% protein, 7,420 mg/kg sodium, 28,912 mg/kg calcium, and 1,924 mg/kg magnesium. The high-energy milling process resulted in a reduction of the particle size from the microscale to the nanoscale. The analysis of the average particle size and polydispersity index indicated that 24 h of milling showed the most optimal results. Furthermore, the functional groups exhibited no significant alteration at 3 milling times (p ≥ 0.05, FTIR analysis)., Conclusions: The high-energy milling method has the potential to reduce the particle size of Stolephorus sp. powder to the nanoscale at the 8- and 24-h milling periods. The powder resulting from the 24-h milling process had a size of 789.3 ±170.7 nm, smooth size distribution, good size uniformity, a polydispersity index of 0.763, no significant change in organic and inorganic compound content, and a calcium/phosphorus ratio that was the closest to that of hydroxyapatite (HAp).

Six ruminal-cannulated nonlactating Holstein Friesian cows (mean body weight:660 ± 42.9 kg) were used to investigate the effect of soybean meal (SBM) supplementation on voluntary rice straw (RS) intake, feed particle size reduction, and passage kinetics in the rumen. They were allocated to two dietary treatments: RS alone or RS supplemented with SBM. Voluntary dry matter intake of RS and total tract fiber digestibility was increased by SBM supplementation (p < 0.05). Supplementation with SBM decreased rumination time per dietary dry matter (DM) and neutral detergent fiber (NDFom) intake (p < 0.01). Particle size distribution in the rumen and total ruminal NDFom digesta weights were not affected by SBM supplementation. However, the disappearance rates of total digesta and large and small particles from the rumen were increased by SBM supplementation (p < 0.01). Moreover, SBM supplementation increased the rate of size reduction in ruminal particles (p < 0.05). In situ disappearance of DM and NDFom of RS in the rumen was greater in SBM-supplemented cows than in nonsupplemented cows (p < 0.05). This study clearly showed that increased ruminal RS particle size reduction, passage, and fermentation due to SBM supplementation accelerated the RS particle clearance from the rumen and resulted in increased voluntary RS intake of dairy cows. [ABSTRACT FROM AUTHOR]

The conditions of size reduction of particles of an emulsion disperse phase during its movement in the holes of the rotor and stator of a high-speed rotary disperser are studied. Analytical relationships that allow determination of the magnitude of tensile forces acting on the ends of the particle located on the sharp edge of the rotor hole were obtained. It is shown that the magnitude of tensile forces depends on the particle mass, angles of the hole edges, diameter, and angular speed of the rotor. As the rotation speed increases and the rotor hole edge angles decrease, the tensile forces acting on the particle ends increase, which increases the probability of its fragmentation into two parts. [ABSTRACT FROM AUTHOR]

This study investigates the effects of particle size reduction at different inoculum-to-substrate ratios and nutrient media supplementation on the assessment of biomethane production from food waste, under batch mesophilic conditions. Two different food waste samples were used and the best method for testing biomethane potential was chosen based on their characterisation and methane yields. Results obtained indicate that Inoculum-to-substrate ratios of 3:1 and 4:1 helped to stabilise test reactors with smaller particle sizes of 1 mm and 2 mm, respectively. Consequently, an overall biomethane yield increase of 38% was reported (i.e., from 393 NmLCH 4 gVS−1 added to 543 NmLCH 4 gVS−1 added). This could potentially imply a better assessment of energy outputs from anaerobic digestion of food waste (i.e., 43.5% higher energy output as electricity from biogas, using commercial scale Combined Heat and Power (CHP) units). Although nutrient media supplementation did not enhance methane yield from optimum inoculum-to-substrate ratio (3:1) and particle size (1 mm), it was found that its application helped to stabilise food waste digestion by avoiding volatile fatty acids accumulation and high propionic-to-acetic acid ratio, consequently, improving the overall test kinetics with 91% lag time reduction from 5.6 to 0.5 days. This work supports the importance of key variables to consider during biomethane potential tests used for assessing methane yields from food waste samples, which in return can potentially increase the throughput of anaerobic digestion system processing food waste, to further increase the overall energy output. • Food waste particle size reduction enhanced material solubilisation. • Inoculum-to-substrate ratio selection depends on substrate's particle size. • Nutrient media supplementation helped to improve anaerobic digestion kinetics. • 38% increase in methane yield was achieved at 1 mm PS and 3:1 ISR. • Up to 43.5% increase in energy output as electricity was achieved. [ABSTRACT FROM AUTHOR]

To better understand the migration properties of hybrid carrageenan from the seaweed tissue during carrageenan extraction, the effect of increasing the seaweed surface area by the mechanical disintegration of gametophyte Chondrus crispus chips was studied under various temperature and time extraction conditions. Dried Chondrus crispus seaweed chips were milled by a rotor beater mill and classified into eight different size fractions by sieving with varying mesh sizes from 50 to 2000 μm. During extraction at 22 °C, the red color of the filtrate increased significantly with the decreasing particle size of the fraction, correlating with the increasing phycoerythrin concentration (from 0.26 mg PE/g dry seaweed in the >2000 μm size fraction to 2.30 mg PE/g dry seaweed in the 2000 μm size fraction to 2.1 ± 0.1 g/kg filtrate in the

The study aimed at optimizing the formulation of metronidazole tablet with Manihot utilissima starch. Starch from one year old Manihot utilissima plant was extracted, processed and analyzed. The processed Manihot ultilissima starch and corn starch (reference standard) were used as formulation test polymers. A physical blend of metronidazole and starch polymer at 4:1, 2:1 and 1:1, was triturated with water/ethanol (1:1) solution of metronidazole, dried and blended with other formulation excipients and pulverized to size for compression. The FT - IR absorption spectrum of the metronidazole-Manihot ultilissima starch add mixture showed no chemical incompatibility. The metronidazole granules containing Manihot ultilissima starch had better particle size distribution and other micromeritic qualities in comparison with formulations of corn starch. Metronidazole tablets produced with the Manihot ultilissima starch gave good compact (9–10 Kgf hardness) and low friability. Using a 6 × 3 contingency table for Two-way analysis of variance (ANOVA) in design without repeated values, and the effect of the starch polymer concentrations on metronidazole dissolution was analyzed. The F-ratio results were greater than the critical value of F-table; and therefore the null hypothesis that the effects of all treatment at different concentration are the same at 5% P value was rejected. The variation from critical difference was more significant at ratio 1:1 of corn and Manihot ultilissima starches. In conclusion, the 1:1 ratio of metronidazole and Manihot ultilissima starch using a combination of co-solvency, particle size reduction and solid dispersion techniques gave optimal tablet formulation.

The effect of reducing particle size on physical properties, the methane yield and energy flow were investigated through the biochemical methane potential (BMP) experiment of aerobic-anaerobic digestion (AAD) of rice straw (RS). The whole straw was crushed through four sieves of different aperture sizes (1, 3, 5, and 7 mm) to obtain the actual and non-uniform particle size distribution (PSD). The results indicated that the actual particle sizes were normally or logarithmic normally distributed. Reducing particle size could significantly promote the aerobic hydrolysis and acidification process, increase the content of volatile fatty acids (VFAs) from 4408.78 to 6225.15 mg/L and the degradation of volatile solids (VS) from 40.56% to 50.49%. The results of path analysis suggested that particle size reduction played an important role in improving lignocellulosic degradability, which was the main factor affecting methane production with the comprehensive decision of 0.4616. The maximum methane production obtained at 1 mm sieve size was 176.47 mLCH4g−1 VS. The phyla of Firmicutes (61.5%), Proteobacteria (9.3%), Chloroflexi (8.3%), Bacteroidetes (4.1%), Cyanobacteria/Chloroplast (4.6%) were mainly responsible for VFAs production and lignocellulose degradation. However, the net negative energy balance was observed at the 1 mm sieve size due to the increased energy input. Therefore, the optimum sieve size for AAD was 3 mm.

Increasing the effectiveness of known, well-tested drugs is a promising low-cost alternative to the search for new drug molecular forms. Powerful approaches to solve this problem are (a) an active drug particle size reduction down to the nanoscale and (b) thermodynamically metastable but kinetically stable crystal modifications of drug acquisition. The combined cryochemical method has been used for size and structural modifications of the antibacterial drug 2,3-quinoxalinedimethanol-1,4-dioxide (dioxidine). The main stage of the proposed technique includes the formation of a molecular vapor of the drug substance, combined with a carrier gas (CO2) flow, followed by a fast condensation of the drug substance and CO2 molecules on a cooled-by-liquid nitrogen surface of preparative cryostate. It was established that the molecular chemical structure of the drug substance remained unchanged during cryochemical modification; however, it led to a significant decrease of the drug particles’ size down to nanosizes and changes in the crystal structures of the solid drug nanoforms obtained. Varying carrier gas (CO2) flow led to changes in their solid phase composition. A higher dissolution rate and changes in antibacterial activity were demonstrated for cryomodified dioxidine samples in comparison to the properties of the initial pharmacopeia dioxidine.

Wheat bran consumption is associated with several health benefits, but its incorporation into food products remains low because of sensory and technofunctional issues. Besides, its full beneficial potential is probably not achieved because of its recalcitrant nature and inaccessible structure. Particle size reduction can affect both technofunctional and nutrition-related properties. Therefore, in this study, wet milling and cryogenic milling, two techniques that showed potential for extreme particle size reduction, were used. The effect of the milling techniques, performed on laboratory and large scale, was evaluated on the structure and physicochemical properties of wheat bran. With a median particle size (d50) of 6 µm, the smallest particle size was achieved with cryogenic milling on a laboratory scale. Cryogenic milling on a large scale and wet milling on laboratory and large scale resulted in a particle size reduction to a d50 of 28–38 µm. In the milled samples, the wheat bran structure was broken down, and almost all cells were opened. Wet milling on laboratory and large scale resulted in bran with a more porous structure, a larger surface area and a higher capacity for binding water compared to cryogenic milling on a large scale. The extensive particle size reduction by cryogenic milling on a laboratory scale resulted in wheat bran with the highest surface area and strong water retention capacity. Endogenous enzyme activity and mechanical breakdown during the different milling procedures resulted in different extents of breakdown of starch, sucrose, β-glucan, arabinoxylan and phytate. Therefore, the diverse impact of the milling techniques on the physicochemical properties of wheat bran could be used to target different technofunctional and health-related properties.

Various approaches have been developed to enhance the solubility or dissolution rate for the delivery of poorly water-soluble molecules. In this work, guided by an in silico solubility sensitivity analysis for oral absorption, a comparative assessment of the biopharmaceutical performance of a jet-milled free base, a tosylate salt, and a 50:50 (w/w) amorphous solid dispersion (ASD) with hydroxypropyl methylcellulose acetate succinate (HPMCAS) of a weak base drug candidate, GDC-3280, was conducted. Successful particle size reduction without amorphization or form change was confirmed for the jet-milled free base. The potential of solubility enhancement and desupersaturation risk were identified for tosylate salt and ASD formulation by measurements of tosylate salt solubility product constant ( K sp ) and amorphous solubility of GDC-3280. In vitro dissolution testing demonstrated dissolution rate improvement for the jet-milled free base when compared with the unmilled free base and confirmed solubility enhancement followed by desupersaturation for GDC-3280 tosylate salt and ASD formulation. A crystallization inhibitor, hydroxypropyl methylcellulose (HPMC), was found to slow down the desupersaturation of tosylate salt solution, providing general insights for the development of pharmaceutical salts with disproportionation risks. Finally, a pharmacokinetic study in dogs showed that the in vivo exposure increased by 1.7- to 2-fold for the tosylate salt and ASD formulation compared with the jet-milled free base, consistent with the in silico solubility sensitivity analysis for the fraction of drug absorbed. Overall, this work provides insights into the evaluation of multiple formulation approaches for enhancing the biopharmaceutical performance of poorly water-soluble drugs.

In the present study, we investigated whether reducing the particle size of wheat bran affects the colonizing microbial community using batch fermentations with cecal inocula from seven different chickens. We also investigated the effect of in-feed administration of regular wheat bran (WB; 1,690 μm) and wheat bran with reduced particle size (WB280; 280 μm) on the cecal microbial community composition of broilers. During batch fermentation, WB280 was colonized by a lactic acid-producing community (Bifidobacteriaceae and Lactobacillaceae) and by Lachnospiraceae that contain lactic acid-consuming butyric acid-producing species. The relative abundances of the Enterobacteriaceae decreased in the particleassociated communities for both WB and WB280 compared to that of the control. In addition, the community attached to wheat bran was enriched in xylandegrading bacteria. When administered as a feed additive to broilers, WB280 significantly increased the richness of the cecal microbiota and the abundance of bacteria containing the butyryl-coenzyme A (CoA):acetate CoA-transferase gene, a key gene involved in bacterial butyrate production, while decreasing the abundances of Enterobacteriaceae family members in the ceca. Particle size reduction of wheat bran thus resulted in the colonization of the bran particles by a very specific lactic acid- and butyric acid-producing community and can be used to steer toward beneficial microbial shifts. This can potentially increase the resilience against pathogens and increase animal performance when the reduced-particle-size wheat bran is administered as a feed additive to broilers. [ABSTRACT FROM AUTHOR]

Chalcogenide semiconductors are widely used, due to their versatile structural, optical and electrical properties. They are used in image sensors, energy conversion, non-volatile memory, and waveguides applications. Due to these versatilities in the properties, nanostructured thin films of TlInS 2 are successfully prepared by thermal evaporation. The average particle size changes due to thermal treatment are examined by X-ray diffraction (XRD), and transmission electron microscope (TEM). A sharp reduction in the average particle size of the pristine nanostructured films is reported upon annealing processes at 423 K and 523 K. Besides, thermal treatment temperatures induce changes in the dispersion parameters viz oscillator energy, dispersion energy, high-frequency dielectric constant and dielectric constant. Of these, only the oscillator energy decreases with the annealing temperatures while all the other parameters increase. Moreover, the non-linear optical calculations have revealed that the nanostructured TlInS 2 films exhibit high third-order nonlinear optical susceptibility of order 10 −11  esu and strong nonlinear refractive index of order 10 −10  esu. [ABSTRACT FROM AUTHOR]

Temperature sweep tests and steady shear properties of five different food hydrocolloids (guar gum, xanthan gum, carboxymethylcellulose, pectin and carrageenan) in two different particle sizes groups have been determined at 25, 40, 60 and 80 °C in 1% aqueous solution. Also, the Scanning Electron Microscopy (SEM) images of gums were taken to investigate the morphological properties of the samples. The particle size and processing temperature significantly affected all rheological parameters of the hydrocolloid solutions. The flow behavior of the samples was fitted to Ostwald de Waele model (R2 = 0.959). The highest n value was recorded at 60 °C for all samples. The most drastic changes in consistency coefficient (K) values of the samples were observed in carrageenan solution and it was ranged from 0.013 to 1.774 Pa.sn before the size reduction and from 0.007 to 0.337 Pa.sn after the size reduction process. As the consistency coefficient (K) and apparent viscosity (η50) decreased with the temperature, the flow behavior index increased in both group of samples. As a result, it was concluded that the increase in processing temperature and size reduction process caused a decrease in resistance of hydrocolloid solutions subjected to the deformation, which is a very important factor affecting the quality and good mouth-feel of products. [ABSTRACT FROM AUTHOR]

While it is well known that particle size reduction impacts the performance of bioprocessing such as anaerobic digestion or composting, there is a relative lack of knowledge about particle size distribution (PSD) in pre-treated organic material, i.e., the distribution of particles across different size ranges. PSD in municipal solid waste (MSW) pre-treated for bioprocessing in mechanical−biological treatment (MBT) was researched. In the first part of this study, the PSD in pre-treated waste at two full-scale MBT plants in the UK was determined. The main part of the study consisted of experimental trials to reduce particle sizes in MSW destined for bioprocessing and to explore the obtained PSD patterns. Shredders and a macerating grinder were used. For shear shredders, a jaw opening of 20 mm was found favourable for effective reduction of particle sizes, while a smaller jaw opening rather compressed the wet organic waste into balls. Setting the shredder jaw opening to 20 mm does not mean that in the output all particles will be 20 mm or below. PSD profiles revealed that different particle sizes were present in each trial. Using different types of equipment in series was effective in reducing the presence of larger particles. Maceration yielded a PSD dominated by very fine particles, which is unsuitable for composting and potentially also for anaerobic digestion. It was concluded that shredding, where equipment is well selected, is effective in delivering a material well suited for anaerobic digestion or composting.

The therapeutic usage of cilostazol is limited owing to its poor aqueous solubility and oral bioavailability. Our aim was to produce cilostazol crystals with small average particle size; besides suitable roundness, narrow particle size distribution and stable polymorphic form to increase its dissolution rate and improve processability. Different conventional crystallization methods with or without sonication were compared with impinging jet crystallization combined with cooling, and the optimization of the various parameters was also implemented. The effects of post-mixing time and temperature difference were studied by means of a full factorial design. The physical properties of powder particles were characterized by, i.a., XRPD, DSC and SEM. The dissolution rate and the contact angle of solid surfaces were also determined to elucidate the relationship between wettability and dissolution. It was observed that impinging jet crystallization combined with cooling is a very effective and reproducible method for reducing the particle size of cilostazol. This method resulted in significantly smaller particle size (d(0.5) = 3−5 μm) and more uniform crystals compared to the original ground material (d(0.5) = 24 μm) or the conventional methods (d(0.5) = 8−14 μm), and it also resulted in a stable polymorphic form and enhanced the dissolution rate.

Purpose: To develop a small-scale set-up to rapidly and accurately determine the intrinsic dissolution rate (IDR) and apparent solubility of poorly water-soluble compounds. Methods: The IDR and apparent solubility (S) were measured in fasted state simulated intestinal fluid (FaSSIF) for six model compounds using wet-milled controlled suspensions (1.0% ( w/w) PVP and 0.2% ( w/w) SDS) and the μDISS Profiler. Particle size distribution was measured using a Zetasizer and the total surface area was calculated making use of the density of the compound. Powder and disc dissolution were performed and compared to the IDR of the controlled suspensions. Results: The IDR values obtained from the controlled suspensions were in excellent agreement with IDR from disc measurements. The method used low amount of compound (μg-scale) and the experiments were completed within a few minutes. The IDR values ranged from 0.2-70.6 μg/min/cm and the IDR/S ratio ranged from 0.015 to 0.23. This ratio was used to indicate particle size sensitivity on intestinal concentrations reached for poorly water-soluble compounds. Conclusions: The established method is a new, desirable tool that provides the means for rapid and highly accurate measurements of the IDR and apparent solubility in biorelevant dissolution media. The IDR/S is proposed as a measure of particle size sensitivity when significant solubilization may occur. [ABSTRACT FROM AUTHOR]

Food binders must be sticky to glue different components together. This study evaluated the impact of homogenization of pea proteins on the stickiness of pea protein – apple pectin mixtures. A reduction in protein particle size was suggested to improve adhesion and cohesion by increasing reactive surface area, resulting in a sticky material. In addition, impact of concentrating methods, namely freeze-drying and vacuum evaporation, on concentrating the homogenized pea protein dispersions was investigated. A reduced particle size of pea proteins upon homogenization led to an increased stickiness of the biopolymer matrix when the proteins were vacuum evaporated as demonstrated by a tack test. This was attributed to a firmer and more cohesive bulk structure demonstrated by rheological, confocal laser scanning microscopy and visual observations. Vacuum evaporation prevented re-aggregation of protein particles compared to freeze-drying since less water was expelled during vacuum evaporation. These results provide new insights into tuning stickiness of biopolymer mixtures. • Homogenization of pea proteins reduced their particle size. • Vacuum evaporation maintained reduced particle size better than freeze-drying. • Pea protein-apple pectin blends with small particles were more cohesive & stickier. [ABSTRACT FROM AUTHOR]

Sediments link hillslopes to river channels. The size of sediments entering channels is a key control on river morphodynamics across a range of scales, from channel response to human land use to landscape response to changes in tectonic and climatic forcing. However, very little is known about what controls the size distribution of particles eroded from bedrock on hillslopes, and how particle sizes evolve before sediments are delivered to channels. Here we take the first steps toward building a geomorphic transport law to predict the size distribution of particles produced on hillslopes and supplied to channels. We begin by identifying independent variables that can be used to quantify the influence of five key boundary conditions: lithology, climate, life, erosion rate, and topography, which together determine the suite of geomorphic processes that produce and transport sediments on hillslopes. We then consider the physical and chemical mechanisms that determine the initial size distribution of rock fragments supplied to the hillslope weathering system, and the duration and intensity of weathering experienced by particles on their journey from bedrock to the channel. We propose a simple modeling framework with two components. First, the initial rock fragment sizes are set by the distribution of spacing between fractures in unweathered rock, which is influenced by stresses encountered by rock during exhumation and by rock resistance to fracture propagation. That initial size distribution is then transformed by a weathering function that captures the influence of climate and mineralogy on chemical weathering potential, and the influence of erosion rate and soil depth on residence time and the extent of particle size reduction. Model applications illustrate how spatial variation in weathering regime can lead to bimodal size distributions and downstream fining of channel sediment by down-valley fining of hillslope sediment supply, two examples of hillslope control on river sediment size. Overall, this work highlights the rich opportunities for future research into the controls on the size of sediments produced on hillslopes and delivered to channels. [ABSTRACT FROM AUTHOR]

The stirred media mill is a piece of process equipment used in comminution, which uses grinding media, beads of ceramic or similar material, to mediate energy transfer between a rotating impeller and a slurry of the particles to be ground. Motion of the media is vital to the action of the mill, but is often assumed to be simple in modelling due to incomplete knowledge in detail. The movement of a media particle in a stirred media mill has been observed using Positron Emission Particle Tracking. The occupancy and the kinetic energy of the particle within the mill have been calculated and plotted in order to examine the effect of tip speed on the particle. The particle path has been shown to be different below, at, and above the impellers indicating the media are subject to different forces in the region of the impellers. Changes in velocity of the particle correspond with changes of height of the particle in the mill, caused by the particle colliding with the impellers. The impeller speed was found to significantly affect media KE distribution in the mill. At higher tip speeds the media particle has lower energy outside the impeller zone compared to in the impeller zone indicating that there is significantly less energy transfer between the zones when the tip speed is increased. Additionally, at high tip speeds the occupancy is low in the high kinetic energy region at the impellers. [ABSTRACT FROM AUTHOR]

To improve the poor water solubility and dissolution rate of the oral hypoglycemic drug glibenclamide, it was molecularly dispersed in Neusilin UFL2, an amorphous synthetic form of magnesium aluminometasilicate, at different proportions; the physicochemical and biopharmaceutical properties, as well as the stability of the four different batches recovered were characterised, and it was determined that complete dispersion of glibenclamide in the amorphous polymer was obtained at the drug to Neusilin ratio of 1 to 2.5. Completely amorphous dispersion was proven by Thermal Analysis and X-Ray Powder Diffractometry. Very small particles were obtained, ranging from approximately 200 to 400 nm. The amorphous batches were physically and chemically stable for the entire duration of experiments. The physicochemical properties of the four batches were compared to those of the starting materials and physical mixtures of Neusilin UFL2 and glibenclamide, the latter showing the typical behaviour of simple mixes, i.e., the additivity of properties of single components. The dissolution studies of the four solid dispersions revealed a very high dissolution rate of the completely amorphous batches (Batches 3 and 4), behaviour that was ascribed to their high Intrinsic dissolution rate due to the amorphous characteristics of the solid dispersions, to their very small particle size, and to the presence of polysorbate 80 that improved solid wettability. The technique under investigation thus proved effective for recovering stable amorphous dispersions of very small particle sizes. [ABSTRACT FROM AUTHOR]

Rye bran of two different particle sizes (coarse: 440 μm and fine: 28 μm) were prepared by milling of commercial rye bran. Coarse and fine rye bran was added into a blend of rye endosperm flour and corn starch (70:30) to achieve two bran levels, 15 or 30%, to produce directly puffed extrudates. A co-rotating twin screw extruder was used with a screw speed of 500 rpm, barrel temperature profile: 40-70-75-90-95-110-110 °C and constant feed rate of 67 g/min. Feed moisture content of 17% was used either as in barrel-water feed or as preconditioning. Fine bran addition effectively improved macrostructural properties as compared to coarse bran through increasing expansion by 3.3–11.7% and piece density by 3.8–10.5%. Reduction of bran particle size significantly ( P < 0.05) increased crispiness by 66.7–203.3%. Particle size reduction of bran had only minor influences on cell wall thickness, cell area and hydrolysis index of the extrudates. Extrudates made with 30% fine bran at in barrel-water feed provided the crispiest extrudates with lower in vitro hydrolysis index. The results demonstrated that the macrostructural and mechanical properties of extrudates containing rye bran can be improved by reducing bran particle size. [ABSTRACT FROM AUTHOR]

Nanocrystals have emerged as a potential formulation strategy to eliminate the bioavailability-related problems by enhancing the initial dissolution rate and moderately super-saturating the thermodynamic solubility. This review contains an in-depth knowledge of, the processing method for formulation, an accurate quantitative assessment of the solubility and dissolution rates and their correlation to observe pharmacokinetic data. Poor aqueous solubility is considered the major hurdle in the development of pharmaceutical compounds. Because of a lack of understanding with regard to the change in the thermodynamic and kinetic properties (i.e., solubility and dissolution rate) upon nanosizing, we critically reviewed the literatures for solubility determination to understand the significance and accuracy of the implemented analytical method. In the latter part, we reviewed reports that have quantitatively studied the effect of the particle size and the surface area change on the initial dissolution rate enhancement using alternative approaches besides the sink condition dissolution. The lack of an apparent relationship between the dissolution rate enhancement and the observed bioavailability are discussed by reviewing the reported in vivo data on animal models along with the particle size and food effect. The review will provide comprehensive information to the pharmaceutical scientist in the area of nanoparticulate drug delivery. [ABSTRACT FROM AUTHOR]

Identification of lead compounds with higher molecular weight and lower aqueous solubility has become increasingly prevalent with the advent of high throughput screening. Poor aqueous solubility of these lipophilic compounds can drastically affect the dissolution rate and subsequently the drug absorbed in the systemic circulation, imposing a significant burden of time and money during drug development process. Various pre-formulation and formulation strategies have been applied in the past that can improve the aqueous solubility of lipophilic compounds by manipulating either the crystal lattice properties or the activity coefficient of a solute in solution or both, if possible. However, despite various strategies available in the armor of formulation scientist, solubility issue still remains an overriding problem in the drug development process. It is perhaps due to the insufficient conceptual understanding of solubility and dissolution phenomenon that hinders the judgment in selecting suitable strategy for improving aqueous solubility and/or dissolution rate. This article, therefore, focuses on (i) revisiting the theoretical and mathematical concepts associated with solubility and dissolution, (ii) their application in making rationale decision for selecting suitable pre-formulation and formulation strategies and (iii) the relevant research performed in this field in past decade. [ABSTRACT FROM AUTHOR]

All- trans retinoic acid (ATRA) is a derivative of retinol (or vitamin A) presenting similar benefits but considerable lower adverse toxicity, mainly in cases of high or long-term therapeutic doses. ATRA showed to be effective in the treatment and/or chemoprevention of several epithelial and hematological malignancies and diverse dermatological and eye diseases however, its low solubility in aqueous media and photosensitivity hinder its wider usage by the conventional administration methods. Supercritical fluids technologies are being widely used to enhance the in vivo bioactivity of this type of drugs both by improving their dissolution rate (using particle size reduction processes) and/or by controlling their release into the media after incorporation into solid polymeric/inorganic matrices (using supercritical impregnation/foaming processes). In both cases the solubility of the drug in the supercritical fluid (usually scCO 2 ) is required for process optimization purposes. Therefore, in this work the solubility of ATRA in scCO 2 was measured at different isotherms (308.2, 318.2 and 328.2 K) and pressures that ranged from 10 up to 30 MPa using a static analytical method. Solubility data were correlated using three commonly used density-based models, namely the Bartle, Chrastil and Méndez-Santiago–Teja models. The solubility of ATRA in scCO 2 was found to be between 1.52 × 10 −6 and 1.84 × 10 −5 in terms of ATRA mole fraction and between 7.50 × 10 −3 and 1.07 × 10 −1 in terms of amount of solid solute per unit of volume of scCO 2 . Fairly good correlation agreement was obtained with all the applied models being the lowest deviations obtained with the Chrastil model. ATRA particles obtained after scCO 2 processing (dissolution in scCO 2 followed by re-precipitation) were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) and in vitro dissolution studies. The results showed that the processed particles maintained their chemical structure and presented enhanced dissolution in aqueous media (PBS:ethanol, 80:20, v/v) when compared with commercial (non-processed) ATRA. [ABSTRACT FROM AUTHOR]

This article reports on particle engineering by a top-down method involving organic solvent-free acoustic cavitation as a wet-grinding procedure. The effects of static and dynamic sonication on particle size reduction methods were compared to each other. The most effective process parameters were determined by a factorial design plan for the particle size distribution of an important active pharmaceutical ingredient, meloxicam, as response factor after sonication. Samples sonicated with appropriate process parameters were dried and investigated. Scanning electron microscopy images showed that the sonication resulted in a rounded shape and micronized size of the particles. Differential scanning calorimetry and X-ray powder diffraction examinations revealed the crystalline structure of the produced meloxicam by both sonication methods. Fourier transform infrared spectroscopy demonstrated that no chemical degradation occurred. Static sonication is recommended primarily for particle size reduction in preclinical samples, where the amount of the drug candidate is very small (e.g. nasal formulation), while dynamic sonication may be suitable for wet-grinding of different active substances to prepare pre-suspension (e.g. micronization and nanonization). [ABSTRACT FROM AUTHOR]

Incineration is an important municipal solid waste management process in Singapore. The incineration bottom ash (IBA) generated may contain heavy metals (HMs) and rare earth elements (REEs) that can cause environmental concerns upon reutilization. In this study, the particle size distribution, density, circularity, and chemical composition of the overall IBA as well as individual size ranges were determined. The particle size reduction characteristics and the mobility of HMs and REEs among different size ranges through ball milling and fluidization processes were examined. Certain HMs were found to present in high concentrations at particular particle size ranges. Mechanisms concerning the mobility of HMs and REEs were revealed. [ABSTRACT FROM AUTHOR]

With the aim of reducing phytic acid content of wheat bran, particle size reduction (from 1,200 to 90 μm), hydrothermal (wet steeping in acetate buffer at pH 4.8 at 55 °C for 60 min) and fermentation (using bakery yeast for 8 h at 30 °C) and combination of these treatments with particle size reduction were applied and their effects on some properties of the bran were studied. Phytic acid content decreased from 50.1 to 21.6, 32.8 and 43.9 mg/g after particle size reduction, hydrothermal and fermentation, respectively. Particle size reduction along with these treatments further reduced phytic acid content up to 76.4 % and 57.3 %, respectively. Hydrothermal and fermentation decreased, while particle size reduction alone or in combination increased bran lightness. With reducing particle size, total, soluble and insoluble fiber content decreased from 69.7 to 32.1 %, 12.2 to 7.9 % and 57.4 to 24.3 %, respectively. The highest total (74.4 %) and soluble (21.4 %) and the lowest insoluble fiber (52.1 %) content were determined for the hydrothermaled bran. Particle size reduction decreased swelling power, water solubility and water holding capacity. Swelling power and water holding capacity of the hydrothermaled and fermented brans were lower, while water solubility was higher than the control. The amount of Fe, Zn and Ca decreased with reducing particle size. Fermentation had no effect on Feand Zn but slightly reduced Ca. The hydrothermal treatment slightly decreased these elements. Amongst all, hydrothermal treatment along with particle size reduction resulted in the lowest phytic acid and highest fiber content. [ABSTRACT FROM AUTHOR]

To improve nanoconfinement of LiBH 4 and MgH 2 in carbon aerogel scaffold (CAS), particle size reduction of MgH 2 by premilling technique before melt infiltration is proposed. MgH 2 is premilled for 5 h prior to milling with LiBH 4 and nanoconfinement in CAS to obtained nanoconfined 2LiBH 4 –premilled MgH 2 . Significant confinement of both LiBH 4 and MgH 2 in CAS, confirmed by SEM–EDS–mapping results, is achieved due to MgH 2 premilling. Due to effective nanoconfinement, enhancement of CAS:hydride composite weight ratio to 1:1, resulting in increase of hydrogen storage capacity, is possible. Nanoconfined 2LiBH 4 –premilled MgH 2 reveals a single–step dehydrogenation at 345 °C with no B 2 H 6 release, while dehydrogenation of nanoconfined sample without MgH 2 premilling performs in multiple steps at elevated temperatures (up to 430 °C) together with considerable amount of B 2 H 6 release. Activation energy ( E A ) for the main dehydrogenation of nanoconfined 2LiBH 4 –premilled MgH 2 is considerably lower than those of LiBH 4 and MgH 2 of bulk 2LiBH 4 –MgH 2 (Δ E A = 31.9 and 55.8 kJ/mol with respect to LiBH 4 and MgH 2 , respectively). Approximately twice faster dehydrogenation rate are accomplished after MgH 2 premilling. Three hydrogen release ( T = 320 °C, P (H 2 ) = 3–4 bar) and uptake ( T = 320–325 °C, P (H 2 ) = 84 bar) cycles of nanoconfined 2LiBH 4 –premilled MgH 2 reveal up to 4.96 wt. % H 2 (10 wt. % H 2 with respect to hydride composite content), while the 1st desorption of nanoconfined sample without MgH 2 premilling gives 4.30 wt. % of combined B 2 H 6 and H 2 gases. It should be remarked that not only kinetic improvement and B 2 H 6 suppression are obtained by MgH 2 premilling, but also the lowest dehydrogenation temperature ( T = 320 °C) among other modified 2LiBH 4 –MgH 2 systems is acquired. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effect of NDF content in highly digestible grass/ clover silage on particle size reduction, mminal stratification, and selective retention in dairy heifers. The reduction in particle size from feed to feces was evaluated and related to feed intake, chewing activity, and apparent digestibility. Four grass/clover harvests (Mixtures of Lolium perenne, Trifolium pratense, and Trifolium repens) were performed from early May to late August at different maturities, at different regrowth stages, and with different clover proportions, resulting in silages with NDF contents of 312, 360, 371, and 446 g/kg DM, respectively, and decreasing NDF digestibility with greater NDF content. Four rumen-fistulated dairy heifers were fed silage at 90% of ad libitum level as the only feed source in a 4 x 4 Latin square design. Silage, ingested feed boluses, medial and ventral mminal digesta, and feces samples were washed with neutral detergent in nylon bags of 10-pm pore size, freeze dried, and divided into small (<0.212 mm), medium (0.212 to 1 mm), and large (LP; >1 mm) particles by dry-sieving. Chewing activity, rumen pool size, and apparent digestibility were measured. Intake of NDF increased linearly from 2.3 to 2.8 kg/d with greater NDF content of forages (P = 0.01), but silages were exposed to similar eating time (P = 0.55) and rumination time per kg NDF (P = 0.35). No linear effect of NDF content was found on proportion of LP in ingested feed boluses {P = 0.31), medial rumen digesta (P = 0.95), ventral rumen digesta (P = 0.84), and feces (P = 0.09). Greater proportions of DM (P < 0.001) and particulate DM ( P = 0.008) were found in medial ruminal digesta compared with ventral rumen, and differences in DM proportion increased with greater NDF content (P = 0.02). Particle size distributions were similar for digesta from the medial and ventral rumen regardless of NDF content of the silages (P > 0.13). The LP proportion was >30% of particles in the ventral and medial rumen, whereas in the feces, the LP proportion was <2%. Particle size stratification of the rumen was undetectable regardless of NDF content of the silages, stressing that the retention mechanism of large undigested particles lies elsewhere than with particle entrapment in the rumen mat. In this study, forage particle breakdown, mminal stratification, and retention of particles in the rumen were not affected by NDF content of highly digestible grass/clover silages. [ABSTRACT FROM AUTHOR]

Since the caecal microbiota of young broilers are not yet able to ferment the dietary fibre (DF) fraction of the feed to a large extent, increasing the accessibility of DF substrates along the gastrointestinal tract is crucial to benefit from the health stimulating metabolic end-products (e.g. butyric acid) generated upon microbial DF fermentation. Therefore, the present study aimed to evaluate the potential of reduced-particle size wheat bran (RPS-WB) and endoxylanases as feed additives to stimulate arabinoxylan (AX) hydrolysis and fermentation along the hindgut of young broilers. To this end, RPS-WB and endoxylanase supplementation were evaluated in a 2 × 2 factorial design using a total of 256 male 1-d-old chicks (Ross 308). Broilers were assigned to 4 dietary treatments: a basal wheat-based diet with (1) no feed additives (control, CTRL), (2) an endoxylanase (XYL; Econase XT 25 at 0.10 g/kg diet), (3) 1% wheat bran with an average reduced particle size of 297 μm (RPS-WB) and (4) an endoxylanase and 1% RPS-WB (RPS-WB + XYL). Each dietary treatment was replicated 8 times and on d 10 and 28, respectively, 24 and 16 broilers per treatment group were euthanised to analyse AX degradation, short-chain fatty acid production and digesta viscosity in the ileum and caecum. Broilers receiving XYL in their diet showed increased AX solubilisation and fermentation at both d 10 and 28 compared to the CTRL group ( P  < 0.05). Adding RPS-WB to the diet stimulated wheat AX utilisation by the primary AX degraders in the caecum at 10 d of age compared to the CTRL group, as observed by the high AX digestibility coefficient for the RPS-WB supplemented group at this young age ( P  < 0.05). At 28 d, RPS-WB supplementation lowered body-weight gains but increased butyric acid concentrations compared to the XYL and CTRL group ( P  < 0.05). Although no synergistic effect for RPS-WB + XYL broilers was observed for AX hydrolysis and fermentation, these findings suggest that both additives can raise a dual benefit to the broiler as a butyrogenic effect and improved AX fermentation along the ileum and caecum were observed throughout the broiler's life., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd.)

In this work we present a novel approach to model the micronization of pharmaceutical ingredients at process scales and times. 3D single-phase fluid-dynamics simulations are used to compute the gas velocity field within a spiral jet mill which are provided as input in a 1D compartmentalized model to calculate solid velocities along the radial direction. The particles size reduction is taken into account through a breakage kernel that is function of gas energy and local solid hold-up. Simulation results are validated against micronization experiments for lactose and paracetamol, comparing the model predictions with D10, D50 and D90 diameters values coming from Design of Experiments isosurfaces. The developed model allows for a fair estimation of the outlet particle size distribution in a short computational time, with very good predictions especially for D90 values. [Display omitted] • A novel decoupled model is developed to study spiral jet milling at process-scales. • The model exploits CFD simulations and 1D compartment-based calculations. • Breakage parameters were defined availing of ad hoc micronization experiments. • The proposed strategy works for brittle and semi-brittle substances. • Model predictions are in good accordance with experiments. [ABSTRACT FROM AUTHOR]