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Author(s):  
Yongyang Liu ◽  
Yaxin Lu ◽  
Zhiyong Tang ◽  
Yuheng Cao ◽  
Dehua Huang ◽  
...  

Axonal transport plays a significant role in the establishment of neuronal polarity, axon growth, and synapse formation during neuronal development. The axon of a naturally growing neuron is a highly complex and multifurcated structure with a large number of bends and branches. Nowadays, the study of dynamic axonal transport in morphologically complex neurons is greatly limited by the technological barrier. Here, a sparse gene transfection strategy was developed to locate fluorescent mCherry in the lysosome of primary neurons, thus enabling us to track the lysosome-based axonal transport with a single-particle resolution. Thereby, several axonal transport models were observed, including forward or backward transport model, stop-and-go model, repeated back-and-forth transport model, and cross-branch transport model. Then, the accurate single-particle velocity quantification by TrackMate revealed a highly heterogeneous and discontinuous transportation process of lysosome-based axonal transport in freely orientated axons. And, multiple physical factors, such as the axonal structure and the size of particles, were disclosed to affect the velocity of particle transporting in freely orientated axons. The combined single-particle fluorescence tracking and TrackMate assay can be served as a facile tool for evaluating axonal transport in neuronal development and axonal transport-related diseases.


Author(s):  
Miftahurrahmah Miftahurrahmah ◽  
Hasnah Ulia ◽  
Harmiwati N. H

Aquilaria Malaccensis Lam. is one of the most popular plants contains essential oil, both of them used by pharmaceutical and also cosmetic industry. The plants used in this study came from Jambi, Indonesia which is known, It’s one of the best quality agarwood in the world. This study aims to determine the best conditions for the yield so that it can be produced on an industrial scale. The study reviewed the effect of yield based on size of particles, ratio of solvent, and the operating time, maceration. The research was carried out in three steps. The first, raw material preparation, fermentation and maceration, and then evaporation. Preparation of raw materials is prepared in three variables, 2-5 cm, ±2cm, and size <40 mesh. Methanol is the solvent that will be used in multiple ratio of solvent to agarwood, its 1:7, 1:9, and 1:11(gr/ml). In addition, the maceration time was varied for each sample, 1 day, 2 days, and 3 days. Based on the research variables, obtained essential oil of agarwood dark brown in colour, with a special fragrance of agarwood. Based on the difference in particle size, it is known that size <40 mesh, yield is 3.16%, while for the larger size, 2-5 cm, the yield is 3.12%. In the variable ratio of the amount of solvent used, it is known that 1:9 (gr/ml) is the best point for yield. At maceration step known that 2-3 days, it doesn’t gives a significant change, 2.12 g for 3 days, and 1.92 g for 2 days.


2021 ◽  
Author(s):  
M Sankareswaran ◽  
M Vanitha ◽  
P. Rajiv ◽  
A. Anbukumaran

Abstract The current investigation reports on a green route, simple and eco-friendly method for synthesis of silica nanoparticles from Phyllantus emblica. Appropriate characterization techniques were employed to assess the crystalline nature, microstructure, size, purity, elemental composition and stability of as-biosynthesized silica nanoparticles. The XRD analysis showed a wide-ranging peak at 22∘ of 2θ value and proved that the nanoparticles were crystalline nature with 32 nm average size of particles. FT-IR studies confirmed the occurrence of metal oxide group and presence of phyto-molecules namely hydroxyl, amide, and carboxyl functional groups, which were responsible for formation and stabilization of silica nanomaterials. TGA and Zeta potential analysis determined that silica nanoparticles are highly thermostable. EDX analysis revealed the purity of nanomaterials and spectra confirmed that formation of silica nanomaterials (72.97 weight percentage of SiO2 content) with low impurities. SEM analysis shows that the particles are spherical in shape with low agglomeration. This research work concluded that the P. emblica was an excellent and reliable green resource for production of highly stable and potential silica nanoparticles.


2021 ◽  
Vol 5 (4) ◽  
pp. 88
Author(s):  
Thamonwan Tattanon ◽  
Premjit Arpornmaeklong ◽  
Sarute Ummartyotin ◽  
Thirawudh Pongprayoon

The motivation of this research work is to develop novel medical material from cuttlebone (calcium source) by L-rhamnose monohydrate (biosurfactant) for aged people. The process can be synthesized biphasic calcium phosphate which is eco-friendly to environment. One of the most important aspects for this work is to use cuttlebone as a naturally occurring calcium source from a local beach in Thailand. It usually contains 90% calcium carbonate. The objective of this research work is to synthesize the biphasic calcium phosphate by hydrothermal reaction. Critical micelle concentrations (CMCs) of 10, 20, 100, 500 and 1000 of L-rhamnose monohydrate were used to control particle size and shape. XRD revealed a mixture of β-tricalcium phosphate and hydroxyapatite powder. SEM reported that the size of particles can be effectively controlled by the addition of L-rhamnose monohydrate, and with the addition of surfactant, size uniformity was achieved. The cytotoxicity test was reported to be in the range of 70–75%. It was remarkable to note that biphasic calcium phosphate synthesized from cuttlebone with the aid of L-rhamnose monohydrate will be considered an excellent candidate as a scaffold material.


2021 ◽  
Author(s):  
Malik Asif ◽  
Shayesta Islam ◽  
Mushtaq A. Malik ◽  
Zaffar Mahdi Dar ◽  
Amjad Masood ◽  
...  

Environmental contamination and the tolerance developed by the pests, pathogens are some of the environmental issues related to the aimless utilization of chemical pesticides. It has became matter of serious concern for environment, food quality and soil health. Nanotechnology, envisaged as a swiftly emerging field has capability to reform food systems in agriculture. Nanotechnology provides an imperishable solution to these problems by the establishment of nano-pesticides. The functional components or the conveyor molecules used are of nano size. The performance of these nano sized particles is much better the traditional pesticides, as the smaller size aids in proper spreading on the pest surface. Amelioration in solubility of operational components, betterment in stability of formulation, gradual liberation of operational components and enhancement in mobility are some of the paramount advantages of nano particles attributed to the minute size of particles and greater surface area. Thus, nano particles have strengthened activity against target pests in comparison to bulk materials. Furthermore, nano-formulations sustain productive use in agriculture by offering systemic properties, uniform leaf coverage and enhanced soil properties. Despite all the positive aspects, it might have certain negative effects as well, like exposure of humans through distinct routes Viz, exposure to nano pesticides either directly or indirectly like adsorption through skin, or inhalation while breathing air or transfer from one energy level to another by taking contaminated food and water.


Author(s):  
Nikolas Stefano ◽  
Daniel Pleissner

Abstract Purpose The present study provides quantitative data on the degree of macroplastic contamination of two conventionally treated arable areas in North Rhine-Westphalia (Germany), which differ only in the use of organic fertilizers (e.g., compost). Methods The plastic contamination of both areas was determined by means of field sampling. The study areas were divided into edge and central areas to minimize and identify direct influences from the boundaries. After cleaning and drying, the collected macroplastic particles were analyzed by phototechnical and optical methods for number and size of particles. Results The arable area with compost fertilization showed a substantially higher macroplastic pollution with 9247 particles per hectare compared to the 220 particles per hectare found on the arable land without compost application. Furthermore, the differences in plastic forms and types on both areas, the presence of plastic directly related to household and garden products, and the homogeneous distribution of plastic particles on the arable area with compost application allow to conclude that compost can be regarded as reason for substantially higher pollution. Areas close to a road showed a higher degree of contamination and differences in the found plastic products compared to the center areas, which indicates littering as a further considerable entry path. Conclusions The causes of plastic contamination of the investigated arable areas (e.g., contaminated compost by improper waste management and littering) are predominantly external to agricultural practices. The knowledge gained contributes to the knowledge about quantities, impacts, and fate of plastic in the environment.


Author(s):  
Jian-Xin Lu

Abstract We present a detail study of dynamically generating a M2 brane from super-gravitons (or D0 branes) in a pp-wave background possessing maximal spacetime SUSY. We have three kinds of dynamical solutions depending on the excess energy which appears as an order parameter signalling a critical phenomenon about the solutions. As the excess energy is below a critical value, we have two branches of the solution, one can have its size zero while the other cannot for each given excess energy. However there can be an instanton tunnelling between the two. Once the excess energy is above the critical value, we have a single solution whose dynamical behavior is basically independent of the background chosen and whose size can be zero at some instant. A by product of this study is that the size of particles or extended objects can grow once there is a non-zero excess energy even without the presence of a background flux, therefore lending support to the spacetime uncertainty principle.


2021 ◽  
Vol 18 (4) ◽  
pp. 119-123
Author(s):  
Doaa Kaduim ◽  
Zaid Mahmoud ◽  
Falah Mousa

The biosynthesis of iron oxide (Fe2O3, also known as haematite) nano particles (NPs) using Hydra helix and Beta vulgaris aqueous extracts were adduced, respectively, where the extracts act as a stabiliser and reductant reagent. The crystal structure and size of particles were investigated using X-ray diffraction (XRD), while the morphology was examined using field emission scanning electron microscopy (FESEM), XRD patterns showed the synthesised nanoparticles with well-crystallised structure from Beta vulgaris extract with size 12 nm, while the results by using Hydra helix showed many peaks back to Goethite phase with 16 nm. The antibacterial and antifungal activity were examined using Staphylococcus (showed inhibition zone diameter 23 mm, 16 mm using Hydra helix and Beta vulgaris, respectively), E. coli (showed no inhibition) and Candida fungi (showed inhibition zone 16 mm, 11 mm using Hydra helix and Beta vulgaris, respectively).


2021 ◽  
Author(s):  
Zheng Yang ◽  
Ning Guo ◽  
Heng Zhang

Based on the Xigeda clay rock exposed in the back mountain of Nanshan Villa in Xichang City, the microstructure changes of Xigeda clay rock before and after water softening were studied by scanning electron microscope and image recognition of PCAS software. The results show that: (1) the clay rock of Xigeda group has flake and layered micro structural characteristics, and the surface of aggregates in natural state has honeycomb characteristics. After water softening, the aggregate particles decompose, the average size of particles becomes smaller, the honeycomb characteristics disappear, and the surface contours of particles become smooth and round. (2) With the increase of water saturation time, the number of aggregate particles and pores increases, the porosity decreases in advance and increases in the later stage. (3) Micro structural changes of the clay rock in Xigeda formation have two stages, in the first stage, the aggregates decompose and the produced fine granular clays fill the original pores, resulting in the decrease of porosity.In the second stage, the fine clay particles further soften, decompose and lose in the water, the porosity increases suddenly.


2021 ◽  
Vol 9 ◽  
Author(s):  
E. Gramsch ◽  
P. Oyola ◽  
F. Reyes ◽  
Y. Vásquez ◽  
M. A. Rubio ◽  
...  

In the last decade, many low-cost monitoring sensors and sensor-networks have been used as an alternative air quality assessment method. It is also well known that these low cost monitors have calibration, accuracy and long term variation problems which require various calibration techniques. In this work PM2.5 and PM10 low cost sensors (Plantower and Nova Fitness) have been tested in five cities under different environmental conditions and compared with collocated standard instruments. Simultaneously, particle composition (organic and black carbon, sulfate, nitrate, chloride, ammonium, and chemical elements) has been measured in the same places to study its influence on the accuracy. The results show a very large variability in the correlation between the low cost sensors and collocated standard instruments depending on the composition and size of particles present in the site. The PM10 correlation coefficient (R2) between the low cost sensor and a collocated regulatory instrument varied from to 0.95 in Temuco to 0.04 in Los Caleos. PM2.5 correlation varied from 0.97 to 0.68 in the same places. It was found that sites that had higher proportion of large particles had lower correlation between the low cost sensor and the regulatory instrument. Sites that had higher relative concentration of organic and black carbon had better correlation because these species are mostly below the 1 μm size range. Sites that had higher sulfate, nitrate or SiO2 concentrations in PM2.5 or PM10 had low correlation most likely because these particles have a scattering coefficients that depends on its size or composition, thus they can be classified incorrectly.


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