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Optimal sizing and placement of STATCOM, TCSC and UPFC using a novel hybrid genetic algorithm-improved particle swarm optimization.

The increase in global power demand has caused most of today's power networks to become overloaded especially in Sub-Saharan Africa. The increased load demand can be met through expansion of existing generation and transmission system. However, construction of new power infrastructure is limited by financing and technical constraints. Thus, power networks have been left to operate at overload conditions with high power losses and many power quality (PQ) problems. Flexible AC Transmission System (FACTS) devices can improve the power transfer capability of the existing transmission networks with

Study on the coal dust deposition fraction and site in the upper respiratory tract under different particle sizes and labor intensities.

In order to study the dust exposure amount and coal dust deposition rule of coal miners under different labor intensity in coal mine environ … ely less affected by respiratory intensity, and the overall distribution was uniform. When the dust particle size increased to 7.07 μm, the total dust deposition fraction in the nasal cavity, pharynx and larynx was in the range of 11.10 %-20.91 %, and increased with the respiratory intensity. When the dust particle size was large, the dust particles of 20 μm an …

Spatial variability of arsenic fractionation in an abandoned arsenic-containing mine: Insights into soil particle sizes and quantitative mineralogical analysis.

Soil particle sizes and mineral phases play a major role in the migration of arsenic (As) in mine. In this study, soil As fractionation and mineralogical composition in different particle sizes soil at naturally mineralized and anthropogenically disturbed zones from an abandoned mine were comprehensively studied. The results showed that soil As contents in anthropogenically disturbed mining zone (MZ), processing zone (PZ), and smelting zone (SZ) were increased with decreasing of soil particle sizes. The contents of As in the fine soil particles (0.45-2 μm) reached to 850-4800 mg·kg-1, which ma…

Evaluation of multi-solvent size exclusion chromatography columns packed with sub-2 μm particles for the characterization of synthetic polymers.

With the recent development of small particle stationary-phases and dedicated instrumentation, the combination of size-exclusion chromatography (SEC) with ultra-high performance liquid chromatography (UHPLC) technology has been realized. It opened up a new polymer analysis technique called UHP-SEC. Although high resolution and fast analysis can be achieved, the multi-solvent suitability for a given column was limited to either organic or aqueous eluents. In this work, the capability of novel SEC columns (AdvanceBio SEC columns) packed with 1.9 μm particles for the characterization of synthetic

Viscosity Measurement of CO2-Solvent Mixtures for the Study of the Morphology and Size of Crystalline Particles Obtained Using Supercritical Antisolvent Precipitation.

The viscosity values of CO2-dimethylphormamide, chloroform, methanol, isopropanol, ethyl acetate, acetone, and dimethyl sulfoxide mixtures were measured at a pressure of 150 bar and a temperature of 313 K. The correlation of the mean size of levofloxacin hydrochloride and malonic acid particles precipitated using the SAS method with the viscosity of the used CO2-solvent mixtures is shown. The high viscosity of the mixtures leads to slower mixing of the solution and the antisolvent. Therefore, crystallization occurs at large fractions of the solvent, and as a consequence at a lower supersaturat

Smaller Is Not Always Better: Large-Size Hollow Polydopamine Particles Act as an Efficient Sun Protection Factor Booster for Sunscreens.

Ultraviolet (UV) radiation from the sun is the most harmful factor for human skin, causing sunburn, melasma, freckles, blemishes, and skin cancer. Sunscreens play a key role in blocking UV absorption on the skin. This study focused on the synthesis of hollow polydopamine (h-PDA), whose structure mimics the naturally occurring melanin in humans, for use as an active ingredient in sunscreens by means of a hard-template-based method. The reactions involve a spontaneous polymerization of a dopamine monomer in the presence of tris(hydroxymethyl)aminomethane (Tris) as a catalyst onto a polystyrene (

Preclinical alveolar ridge preservation using small-sized particles of bone replacement graft in combination with a gelatin cryogel scaffold.

BACKGROUND: Particulate anorganic bovine bone matrix (ABBM) is extensively used for alveolar ridge preservation (ARP). This study evaluates the potential of ABBM/gelatin cryogel scaffold of regular (250 to 1,000 μm) and small (50 to 100 μm) particles for ARP. METHODS: ABBM was either condensed in a gypsum ring to simulate filling of ABBM in a defect or incorporated into a gelatin cryogel scaffold to disperse ABBM. Condensed regular-sized or small-sized ABBM (rABBM or sABBM) (± bone morphogenetic protein [BMP]-2) were subcutaneously implanted in rats to evaluate biocompatibility and osteogenic

Effects of two alfalfa preparations with different particle sizes on the gastric mucosa in weanlings: alfalfa chaff versus alfalfa pellets.

BACKGROUND: Feeding alfalfa hay is often recommended for its buffering components, like protein and calcium, to prevent lesions of the gastric mucosa in horses. Until now, there has been no information regarding the influence of alfalfa particle size on the gastric mucosa. The aim of this study was to investigate the effects of feeding two alfalfa preparations with different particle sizes (alfalfa chaff vs alfalfa pellets) in comparison with grass hay on the gastric mucosa in weanling horses. We hypothesized that feeding a high proportion of fine alfalfa particles would negatively impact gast…

Association between HDL particles size and myeloperoxidase/ paraoxonase-1 (MPO/PON1) ratio in patients with acute coronary syndrome.

Myeloperoxidase (MPO) and paraoxonase-1 (PON1) are inflammatory and anti-inflammatory enzymes, respectively that have been involved in the p … PON1 ratio and HDL mean size in patients with ACS. Amount of the enzymes and their relations to HDL particle size in patients with ACS may play a part in the pathogenesis of ACS. Also, MPO/PON1 ratio may be a robust predictor of ACS.

Comparative hazard identification of nano- and micro-sized cerium oxide particles based on 28-day inhalation studies in rats.

There are many uncertainties regarding the hazard of nanosized particles compared to the bulk material of the parent chemical. Here, the authors assess the comparative hazard of two nanoscale (NM-211 and NM-212) and one microscale (NM-213) cerium oxide materials in 28-day inhalation toxicity studies in rats (according to Organisation for Economic Co-operation and Development technical guidelines). All three materials gave rise to a dose-dependent pulmonary inflammation and lung cell damage but without gross pathological changes immediately after exposure. Following NM-211 and NM-212 exposure,

Multi-environment evaluation of proso millet identifies stable genotypes and reveals the roles of amylose content and particle size distribution in processing quality.

Proso millet quality is jointly determined by genotype and genotype-by-environment interaction (GEI). Herein, 18 genotypes grown across 8 ec … d trait performance. The high starch group (HSG) exhibited higher amylose content (14.42%), smaller particle size (34.41 μm), superior pasting behavior, and better cooking performance than those by the low starch group (LSG). Notably, the low-starch environment attenuated particle aggregation and textural hardness in HSG. Collectively, genotype predominantly re …

Effect of different feed particle size on digestive tract morphology, digesta viscosity, nutrient retention, and blood biochemical parameters in slow-growing broiler chickens.

The study evaluated the effect of feed particle size on health and performance indicators in slow-growing broiler chickens. Performance traits, digestive tract morphology, digesta viscosity, nutrient retention, and blood biochemical parameters were assessed in 120 one-day-old male Hubbard JA57 broilers divided into three dietary groups with five replicates, differing only in feed particle size: coarse (CG), medium (MG), and fine (FG). The Geometric Mean Diameter (GMD) of grower and finisher was 1.06 mm for CG, 0.89 mm for the MG and 0.66 mm for the FG. Broilers fed by coarse diet had higher we…

Влияние инженерного распределения твердых частиц обычного портовых цемента на дополнительный цемент: сравнительный анализ эффективности с коммерческим портландским цементом.

В этом исследовании рассматривается критическая взаимосвязь между распределением частиц по размеру (PSD) и соединениями Бога, при этом подчеркивается их важнейшая роль в повышении прочности цемента на раннем этапе при одновременном обеспечении устойчивости. В ходе исследования изучаются экспериментальные процедуры, в результате чего коммерческий обычный портленд цемент (К-ОПК) подвергается измельчению, что приводит к специфическому изысканию. 5390 см2/г, именуемый "стимулятором (S)". Преобразование этого стимулятора в стандарт C-OPC при точно калиброванном 45% Соотношение веса (именуемое "S45"

Совпадение в аннотации оригинала
This study explores the critical interplay between particle size distribution (PSD) and Bogue's compounds, highlighting their essential roles in enhancing the early strength of cement while ensuring sustainability. The research explores experimental procedures by subjecting commercial ordinary Portland cement (C-OPC) to a grinding process, resulting in a spe…

FRET-based analysis on the structural stability of polymeric micelles: Another key attribute beyond PEG coverage and particle size affecting the blood clearance.

Various attributes of micelles, such as PEG density and particle size, are considered to be related to blood clearance. The structural stability of micelles is another key attribute that will affect the in vivo fate. This study employed fluorescence resonance energy transfer (FRET) analysis to guide the preparation of polymeric micelles with different structural stability. Micelles prepared using copolymers with longer hydrophobic blocks showed higher structural stability; emulsification was a better method than nanoprecipitation to prepare stable micelles. The fast chain exchange kinetics and…

Sunlight-Powered Reverse Water Gas Shift Reaction Catalysed by Plasmonic Au/TiO2 Nanocatalysts: Effects of Au Particle Size on the Activity and Selectivity.

This study reports the low temperature and low pressure conversion (up to 160 °C, p = 3.5 bar) of CO2 and H2 to CO using plasmonic Au/TiO2 nanocatalysts and mildly concentrated artificial sunlight as the sole energy source (up to 13.9 kW·m-2 = 13.9 suns). To distinguish between photothermal and non-thermal contributors, we investigated the impact of the Au nanoparticle size and light intensity on the activity and selectivity of the catalyst. A comparative study between P25 TiO2-supported Au nanocatalysts of a size of 6 nm and 16 nm displayed a 15 times higher activity for the smaller particles…

Effects of feed form and particle size, and pellet binder on performance, digestive tract parameters, intestinal morphology, and cecal microflora populations in broilers.

This study was conducted to assess the effects of feed form (FF), particle size (PS), and pellet binder (PB) on performance, digestive tract parameters, intestinal morphology, and cecal microflora populations in broiler chicks. Two FF (mash and pellet), two feed PS (fine and coarse), and two levels of PB (0 and 3%) were evaluated in a completely randomized design with a 2 × 2 × 2 factorial arrangement of treatments. A total of 256 one-day-old male Ross 308 chicks were allocated into 8 treatments consisting of 8 replicates (4 birds/cage) with equal weight from 25 to 42 d of age. The results sho…

Feeding forages with reduced particle size in a total mixed ration improves feed intake, total-tract digestibility, and performance of organic dairy cows.

The optimal utilization of forages is crucial in cattle production, especially in organic dairy systems that encourage forage-based feeding with limited concentrate amounts. Reduction of the particle size of forages is known to improve feed intake and thus might be a viable option to help cows cope with less nutrient-dense feeds. The main aim of this study was to evaluate the effects of reducing forage particle size with a geometric mean of 52 mm (conventional particle size; CON) to 7 mm (reduced particle size; RED) in a high-forage diet (80% of dry matter) on dairy cows' sorting behavior, fee…

Acute intravenous exposure to silver nanoparticles during pregnancy induces particle size and vehicle dependent changes in vascular tissue contractility in Sprague Dawley rats.

The use of silver nanoparticles (AgNP) raises safety concerns during susceptible life stages such as pregnancy. We hypothesized that acute i … tile force in both uterine and aortic vessels. Intravenous AgNP exposure during pregnancy displayed particle size and vehicle dependent moderate changes in vascular tissue contractility, potentially influencing fetal blood supply.

Comparative phototoxicity of nanoparticulate and bulk ZnO to a free-living nematode Caenorhabditis elegans: the importance of illumination mode and primary particle size.

The present study evaluated phototoxicity of nanoparticulate ZnO and bulk-ZnO under natural sunlight (NSL) versus ambient artificial laborat … ed greater phototoxicity than bulk-ZnO despite their similar size of aggregates, suggesting primary particle size is more important than aggregate size in determining phototoxicity.

Effects of Different Particle Sizes of Ultrafine Indica Rice Flour and Lactobacillus casei on the Fermentation and Flavor Characteristics of Danling Dongba.

This study aimed to enhance the flavor and quality of Danling Dongba, a traditional fermented rice product, by preparing ultrafine indica rice flours using fluidized bed airflow crushing. Flours with particle sizes of 20.16, 17.16, and 12.22 μm were fermented with Lactobacillus plantarum 550 (L. plantarum 550), Lactobacillus fermentum GF1800 (L. fermentum GF1800), and Lactobacillus paracasei S6 (L. paracasei S6) under optimized conditions. The 12.22 μm flour showed the best performance, with a water absorption index of 2.32 g/g, solubility of 2.05%, swelling power of 9.26 g/g, and peak viscosi…