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Environmental Science and Pollution... May 2023It is of great significance to study the spatial differentiation of surface gravel in northern Tibet Plateau for regional ecological environment restoration. In this...
It is of great significance to study the spatial differentiation of surface gravel in northern Tibet Plateau for regional ecological environment restoration. In this paper, the particle size and spatial position of the surface gravel are studied. On the basis of the impact factors of topography, vegetation, land use, meteorology, soil, social economy, etc., the quantitative attribution of the gravel particle size is studied in the geomorphological type areas of the northern Tibetan Plateau by using geographic detector and regression analysis. The experimental conclusions are as follows: Firstly, the explanatory power of each impact factor to gravel particle size and the coupling degree between factors are different in different geomorphological types. Among the impact factors, NDVI and land use types are the dominant factors that determine the spatial heterogeneity of gravel particle size. However, in extremely high mountain areas, the explanatory power of altitude factor gradually increases with the increase of topographic relief. Secondly, two-factor interaction is helpful to enhance the explanatory power of spatial heterogeneity of gravel particle size. Except for the interaction of altitude factor in the high relief but extremely high-altitude mountains, the interaction of NDVI and other important factors is mostly found in other regions. Among them, the interaction between NDVI and land use type is the most significant. Thirdly, the areas with high gravel particle size identified by the risk detector are mainly areas with high vegetation coverage and weak external erosion, such as shrubbery, wooded land, and high-coverage grassland. Therefore, the specific conditions of different regions should be fully considered in the study of the spatial heterogeneity of gravel size in the northern Tibetan Plateau.
Topics: Tibet; Particle Size; Environment; Soil; Altitude; Ecosystem; China
PubMed: 37017841
DOI: 10.1007/s11356-023-26750-7 -
ACS Nano Jul 2019Living cells achieve precise control of shape and size through sophisticated biochemical machinery. However, such precision is extremely challenging to emulate in... (Review)
Review
Living cells achieve precise control of shape and size through sophisticated biochemical machinery. However, such precision is extremely challenging to emulate in artificial cellular compartments. So far, various physicochemical and mechanical interventions have been employed to tailor the dimensions of model systems such as liposomes, emulsions, coacervates, and polymer capsules. In this Perspective, we discuss the state of the art in artificial cell research in controlling shape and size and the challenges that need to be addressed.
Topics: Artificial Cells; Particle Size; Surface Properties
PubMed: 31298028
DOI: 10.1021/acsnano.9b05112 -
Journal of Environmental Quality Sep 2020Nutrients excreted from animals affect the nutritive value of manure as a soil amendment as well as the composition of gases emitted from manure storage facilities....
Nutrients excreted from animals affect the nutritive value of manure as a soil amendment as well as the composition of gases emitted from manure storage facilities. There is a dearth of information, however, on how diet type in combination with dietary particle size affects nutrients deposited into manure storage facilities and how this affects manure composition and gas emissions. To fill this knowledge gap, an animal feeding trial was performed to evaluate potential interactive effects between feed particle size and diet composition on manure characteristics and manure-derived gaseous emissions. Forty-eight finishing pigs housed in individual metabolism crates that allowed for daily collection of urine and feces were fed diets differing in fiber content and particle size. Urine and feces were collected and stored in 446-L stainless steel containers for 49 d. There were no interactive effects between diet composition and feed particle size on any manure or gas emission parameter measured. In general, diets higher in fiber content increased manure nitrogen (N), carbon (C), and total volatile fatty acid (VFA) concentrations and increased manure VFA emissions but decreased manure ammonia emissions. Decreasing the particle size of the diet lowered manure N, C, VFAs, phenolics, and indole concentrations and decreased manure emissions of total VFAs. Neither diet composition nor particle size affected manure greenhouse gas emissions.
Topics: Animal Feed; Animals; Diet; Gases; Manure; Particle Size; Swine
PubMed: 33016445
DOI: 10.1002/jeq2.20112 -
The Science of the Total Environment Apr 2022An in-depth understanding of particle size distribution as well as total suspended solids (TSS) in surface runoff is essential for managing urban diffuse pollution. In...
An in-depth understanding of particle size distribution as well as total suspended solids (TSS) in surface runoff is essential for managing urban diffuse pollution. In this study, field experiments and model simulation were undertaken to explore and confirm the dynamic runoff behaviour of TSS and their influencing factors. Field observation results showed that samples with high TSS concentrations contained coarser particles (>100 μm) during three natural rainfall events. Particle size distribution as well as road-deposited sediments (RDS) amount before and after these rainfall events also confirmed that a higher percentage of washed-off coarser particles resulted in higher TSS concentrations in surface runoff water. The impacts of rainfall characteristics, urban-rural gradients, surface roughness, and climate difference on particle distribution as well as TSS concentration were analyzed using the wash-off formula of particle size. These factors mainly affected the contribution rate of RDS to TSS by altering particle size composition; rates ranged from 4% to 44% under different rainfall characteristics. The critical particle size (<100 μm) was developed according to the mass percentage of particles with different sizes in RDS and TSS. Our results can provide a simple and effective way of assessing RDS contribution to TSS in surface runoff.
Topics: Environmental Monitoring; Environmental Pollution; Particle Size; Rain; Water Movements; Water Pollutants, Chemical
PubMed: 35016944
DOI: 10.1016/j.scitotenv.2021.152533 -
Molecules (Basel, Switzerland) Apr 2022The assessment of active pharmaceutical ingredient (API) particle size and morphology is of great importance for the pharmaceutical industry since it is expected to...
The assessment of active pharmaceutical ingredient (API) particle size and morphology is of great importance for the pharmaceutical industry since it is expected to significantly affect physicochemical properties. However, very few methods are published for the determination of API morphology and particle size of film-coated (FC) tablets. In the current study we provide a methodology for the measurement of API particle size and morphology which could be applied in several final products. Bismuth Oxide 120 mg FC Tabs were used for our method development, which contain bismuth oxide (as tripotassium dicitratobismuthate (bismuth subcitrate)) as the active substance. The sample preparation consists of partial excipient dissolution in different solvents. Following this procedure, the API particles were successfully extracted from the granules. Particle size and morphology identification in Bismuth Oxide 120 mg FC Tabs was conducted using micro-Raman mapping spectroscopy and ImageJ software. The proposed methodology was repeated for the raw API material and against a reference listed drug (RLD) for comparative purposes. The API particle size was found to have decreased compared to the raw API, while the API morphology was also affected from the formulation manufacturing process. Comparison with the RLD product also revealed differences, mainly in the API particle size and secondarily in the crystal morphology.
Topics: Bismuth; Excipients; Particle Size; Tablets
PubMed: 35458800
DOI: 10.3390/molecules27082602 -
IET Nanobiotechnology Feb 2021Nanomicelles are self-assembling nanosized (usually with particle size within a range of 10 to 100 nm) colloidal dispersions with a hydrophobic core and hydrophilic... (Review)
Review
Nanomicelles are self-assembling nanosized (usually with particle size within a range of 10 to 100 nm) colloidal dispersions with a hydrophobic core and hydrophilic shell. Owing to its size, solubility, customised surface or its exposure to the environment, nanomicelles show some unique or novel characteristics, which makes it multifunctional and thus makes its use indispensable in biomedical application and various other fields. This review presents the unique properties of nanomicelles that makes it different from other particles and paves its way to be used as drug delivery agent and many other biological uses or applications. It also emphasises on the drug encapsulation ability of the nanomicelles and different technique of drug loading and delivery along with its advantages and disadvantages.
Topics: Drug Carriers; Drug Delivery Systems; Hydrophobic and Hydrophilic Interactions; Micelles; Nanoparticles; Particle Size; Solubility
PubMed: 34694727
DOI: 10.1049/nbt2.12018 -
Respiratory Care Oct 2021The purpose of this study was to evaluate how factors (ambient temperature, shaking the inhaler before use, suspension of the inhaler in water, and the variation over...
BACKGROUND
The purpose of this study was to evaluate how factors (ambient temperature, shaking the inhaler before use, suspension of the inhaler in water, and the variation over the lifetime of the inhaler) affect the particle-size distributions from albuterol HFA inhalers.
METHODS
We used a laser particle-size analyzer to measure the percentage of particles in the 1- to 5-μm range (fine-particle fraction) serially 2,500 times per second to obtain a window of useful measurements with each inhaler actuation. We compared the inhaler performance results as follows: cold versus hot, full versus partial versus empty inhaler actuations, shaken versus unshaken, and inhaler characteristics after water submersion.
RESULTS
The effect of temperature was as follows: fine-particle fraction was 14.4% at 5°C, 37.9% at 24 - 25°C, and 38.1% at 45°C. The fine-particle fraction at the start, middle, end, and past the end of the inhaler's rated lifetime were 37.9, 26.3, 27.9, and 22.0%, respectively. Shaking the inhaler did not improve the inhaler's fine-particle fraction. Submerging the inhaler reduced the fine-particle fraction to 14.3% without purging and to 20.5% with purging compared with the 42.1% for the control inhaler, which was not submerged.
CONCLUSIONS
Temperature made a difference, with cold inhalers producing a lower fine-particle fraction. The early portion of the inhaler had a better fine-particle fraction than the middle and end of the inhaler's lifespan. We could not demonstrate that shaking the inhaler had a significant effect on the fine-particle fraction. Submerging the inhaler in water significantly reduced the fine-particle fraction.
Topics: Aerosols; Albuterol; Humans; Metered Dose Inhalers; Nebulizers and Vaporizers; Particle Size
PubMed: 34230213
DOI: 10.4187/respcare.08858 -
Acta Biomaterialia Mar 2023Endoscopic submucosal dissection (ESD) is a minimally invasive technique that is widely used to remove gastrointestinal tumors. However, because the walls of the...
Endoscopic submucosal dissection (ESD) is a minimally invasive technique that is widely used to remove gastrointestinal tumors. However, because the walls of the duodenum and large intestine are thin, perforation can easily occur after ESD. We have previously reported that alkyl group-modified Alaska pollock gelatin-based microparticles (C10Ps) formed a colloidal gel that could adhere to defects and close perforations, driven by hydrophobic interactions. The present study focused on the effect of particle size on the colloidal gel properties and the floatation of C10Ps in the air in the delivery of C10Ps. We prepared C10Ps with different particle sizes from 0.1 to 100 µm. The storage modulus and adhesion strength of the C10P colloidal gel increased with decreasing particle size. All the C10Ps formed a colloidal gel layer on duodenum tissue after being sprayed from an endoscopic device. The underwater stability and burst strength of C10Ps with a particle size of 0.1 and 1 µm were higher than for larger C10Ps. Floating of the small-sized C10Ps in the air was observed. The results indicated that C10Ps with a size of 1 µm had suitable properties for use in endoscopic treatments. STATEMENT OF SIGNIFICANCE: We previously reported tissue adhesive microparticles as a spray-deliverable wound dressing in gastrointestinal tissues. However, their functions depending on particle size have not yet been clarified. In the present study, we prepared decyl group-modified Alaska pollock gelatin nano and microparticles (C10Ps) with different particle sizes from 0.1 to 100 µm and evaluated the effect of particle size on the colloidal gel properties (rheological property, underwater stability and perforation-closing ability) and the floatation of C10Ps in the air in the delivery of C10Ps.
Topics: Humans; Particle Size; Tissue Adhesions; Gelatin; Gastrointestinal Tract; Bandages; Treatment Outcome
PubMed: 36706853
DOI: 10.1016/j.actbio.2023.01.041 -
AAPS PharmSciTech Oct 2022Computational modeling, machine learning, and statistical data analysis are increasingly utilized to mitigate chemistry, manufacturing, and control failures related to... (Review)
Review
Computational modeling, machine learning, and statistical data analysis are increasingly utilized to mitigate chemistry, manufacturing, and control failures related to particle properties in solid dosage form manufacture. Advances in particle characterization techniques and computational approaches provide unprecedented opportunities to explore relationships between particle morphology and drug product manufacturability. Achieving this, however, has numerous challenges such as producing and appropriately curating robust particle size and shape data. Addressing these challenges requires a harmonized strategy from material sampling practices, characterization technique selection, and data curation to provide data sets which are informative on material properties. Herein, common sources of error in particle characterization and data compression are reviewed, and a proposal for providing robust particle morphology (size and shape) data to support modeling efforts, approaches for data curation, and the outlook for modeling particle properties are discussed.
Topics: Powders; Data Curation; Drug Industry; Particle Size; Computer Simulation
PubMed: 36261755
DOI: 10.1208/s12249-022-02434-2 -
Pest Management Science Apr 2021Safe and efficient nanopesticides for pest control have attracted attention because of their ability to enhance target efficiency and reduce undesirable side effects....
BACKGROUND
Safe and efficient nanopesticides for pest control have attracted attention because of their ability to enhance target efficiency and reduce undesirable side effects. Nanoformulations have a significant role in solving the problem of water solubility for insoluble drugs. However, there are few studies on the physicochemical properties and biological activities of pesticides of different particle sizes and remains unclear how these key physicochemical properties are affected by particle size. In this study, a series of glucose-loaded lambda-cyhalothrin nanoparticles (LCNs) with a tunable size were developed via shearing emulsification and carrier loading in order to evaluate insecticidal action.
RESULTS
The mean particle sizes of the LCNs were 50.6, 115.2 and 221 nm. The wettability, dispersibility and stability of nanoparticles were particle size-dependent, and were mainly determined by particle size and the uniformity of distribution. Furthermore, the insecticidal activity of LCNs was inversely proportional to the particle size.
CONCLUSION
This study not only provides a facile technology for the preparation of nanopesticides with a tunable particle size, but also clarifies the effect of particle size on the performance of pesticides. © 2020 Society of Chemical Industry.
Topics: Nanoparticles; Nitriles; Particle Size; Pyrethrins
PubMed: 33342015
DOI: 10.1002/ps.6236