scholarly journals The Influence of Starch Modification with Amylosucrase Treatment on Morphological Features

Processes ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 1409
Author(s):  
Hyeyoung Lee ◽  
Inmyoung Park
Keyword(s):  
Particle Size ◽  
Cross Section ◽  
Resistant Starch ◽  
Flat Surface ◽  
Particle Sizes ◽  
Particle Size Analyzer ◽  
The Mean ◽  
Waxy Corn ◽  
Slowly Digestible Starch ◽  
Scanning Electron

Amylosucrase (AS) is a starch-modifying enzyme from Neisseria polysaccharea used to produce low-glycemic starches such as slowly digestible starch (SDS) and resistant starch (RS). The morphology of native, control, and AS-modified waxy corn starches (230 and 460 U) was examined using a particle size analyzer and field-emission scanning electron microscopy (FE-SEM). AS modification of the starch elongated the glucose and resulted in higher SDS and RS contents. The mean particle sizes of the control, 230 U-AS-, and 460 U-AS-treated starches were 56.6 µm, 128.0 µm, and 176.5 μm, respectively. The surface of the 460 U-AS-treated starch was entirely porous and coral-like, while the 230 U-AS-treated starch had a partial dense and flat surface which did not react with AS. FE-SEM of the granule cross section confirmed that the center contained a dense and flat region without any evidence of AS reaction to either of the AS-treated starches. It was assumed that the particle size and porous and sponge-like particle features might be related to the SDS and RS fractions.

A Preliminary Study on the Anti-Mosquito Nanocapsule

2014 ◽  
Vol 487 ◽  
pp. 98-101 ◽  
Author(s):  
Jun Hua Wang ◽  
Gang Huang ◽  
Yong Tang Jia
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Particle Size ◽  
Emulsion Polymerization ◽  
Ethyl Acrylate ◽  
Particle Size Analyzer ◽  
Micro Emulsion ◽  
The Mean ◽  
Preliminary Study ◽  
Scanning Electron

Anti-mosquito nanocapsules were prepared using the copolymer of styrene (ST) and ethyl acrylate (EA) as wall and deet as core by micro-emulsion polymerization. The mean particle size of nanocapsules was about 424nm and the loading of deet was about 73% under the conditions of 2% SDS as emulsifier and the ratio of core/wall 1:1. Scanning electron microscopy and laser particle size analyzer were employed to characterize the nanocapsules.

Behaviours of Zinc and Lead in Blast Furnace of Baotou Iron and Steel Group Co.

2011 ◽  
Vol 194-196 ◽  
pp. 306-309 ◽  
Author(s):  
Fang Zhang ◽  
Sheng Li An ◽  
Guo Ping Luo ◽  
Shi Zhong Zhang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Particle Size ◽  
Blast Furnace ◽  
Particle Sizes ◽  
Iron And Steel ◽  
X Ray ◽  
Lead And Zinc ◽  
Particle Size Analyzer ◽  
Scanning Electron

The balance calculation of zinc and lead of No.1 BF of Baotou Iron and Steel Group Co. was performed in this research. The particle sizes of BF dusts were measured by LS230 laser particle size analyzer. The micrology of sinter and dusts were investigated with scanning electron microscopy (SEM, Hitachi S-3000) coupled with an energy-dispersive X-ray analysis (EDX). The results show that the general burdens of zinc and lead in No. 1 mainly came from sinter and pellet. The burdens of zinc and lead in No.1 BF were 645.45g/t and 370.33 g/t respectively, which were too much to need take some measures. Among the gas ash, the particle size of baghouse dust was minimal, but the contents of lead and zinc were highest. So the BF baghouse dust isn’t appropriate to recover as the sintering materials. The speciation of lead is PbO, PbCl3 and metallic Pb, but zinc never presents as metal in BF dusts.

Isolasi Dan Karakterisasi Bentonit Alam Menjadi Nanopartikel Monmorillonit

2018 ◽  
Vol 3 (1) ◽  
pp. 12 ◽  
Author(s):  
Zaimahwati Zaimahwati ◽  
Yuniati Yuniati ◽  
Ramzi Jalal ◽  
Syahman Zhafiri ◽  
Yuli Yetri
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Particle Size ◽  
Surface Morphology ◽  
Average Diameter ◽  
Particle Size Analyzer ◽  
Ft Ir ◽  
Scanning Electron ◽  
Sedimentation Processes

<p>Pada penelitian ini telah dilakukan isolasi dan karakterisasi bentonit alam menjadi nanopartikel montmorillonit. Bentonit alam yang digunakan diambil dari desa Blangdalam, Kecamatan Nisam Kabupaten Aceh Utara.  Proses isolasi meliputi proses pelarutan dengan aquades, ultrasonic dan proses sedimentasi. Untuk mengetahui karakterisasi montmorillonit dilakukan uji FT-IR, X-RD dan uji morfologi permukaan dengan Scanning Electron Microscopy (SEM). Partikel size analyzer untuk menganalisis dan menentukan ukuran nanopartikel dari isolasi bentonit alam. Dari hasil penelitian didapat ukuran nanopartikel montmorillonit hasil isolasi dari bentonit alam diperoleh berdiameter rata-rata 82,15 nm.</p><p><em>In this research we have isolated and characterized natural bentonite into montmorillonite nanoparticles. Natural bentonite used was taken from Blangdalam village, Nisam sub-district, North Aceh district. The isolation process includes dissolving process with aquades, ultrasonic and sedimentation processes.  The characterization of montmorillonite, FT-IR, X-RD and surface morphology test by Scanning Electron Microscopy (SEM). Particle size analyzer to analyze and determine the size of nanoparticles from natural bentonite insulation. From the research results obtained the size of montmorillonite nanoparticles isolated from natural bentonite obtained an average diameter of 82.15 nm.</em></p>

scholarly journals MINERAL ABUNDANCE AND PARTICLE SIZE DISTRIBUTION DERIVED FROM IN-SITU SPECTRA MEASUREMENTS OF YUTU ROVER OF CHANG’E-3

2017 ◽  
Vol XLII-3/W1 ◽  
pp. 85-89
Author(s):  
H. Lin ◽  
X. Zhang ◽  
Y. Yang ◽  
X. Wu ◽  
D. Guo
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Landing Site ◽  
Radiative Transfer Model ◽  
Transfer Model ◽  
Particle Sizes ◽  
The Mean ◽  
The Difference ◽  
Yutu Rover

From geologic perspective, understanding the types, abundance, and size distributions of minerals allows us to address what geologic processes have been active on the lunar and planetary surface. The imaging spectrometer which was carried by the Yutu Rover of Chinese Chang’E-3 mission collected the reflectance at four different sites at the height of ~&amp;thinsp;1&amp;thinsp;m, providing a new insight to understand the lunar surface. The mineral composition and Particle Size Distribution (PSD) of these four sites were derived in this study using a Radiative Transfer Model (RTM) and Sparse Unmixing (SU) algorithm. The endmembers used were clinopyroxene, orthopyroxene, olivine, plagioclase and agglutinate collected from the lunar sample spectral dataset in RELAB. The results show that the agglutinate, clinopyroxene and olivine are the dominant minerals around the landing site. In location Node E, the abundance of agglutinate can reach up to 70&amp;thinsp;%, and the abundances of clinopyroxene and olivine are around 10&amp;thinsp;%. The mean particle sizes and the deviations of these endmembers were retrieved. PSDs of all these endmembers are close to normal distribution, and differences exist in the mean particle sizes, indicating the difference of space weathering rate of these endmembers.

scholarly journals PEMBUATAN DAN KARAKTERISASI NANOPARTIKEL EKSTRAK ETANOL TEMU KUNCI (Boesenbergia pandurata) PADA BERBAGAI VARIASI KOMPOSISI KITOSAN

2017 ◽  
Vol 6 (1) ◽  
pp. 31 ◽  
Author(s):  
Dessy Kurniasari ◽  
Sri Atun
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Particle Size ◽  
Particle Size Analyzer ◽  
Scanning Electron

Tujuan penelitian ini adalah untuk membuat dan mengetahui karakteristik nanopartikel dari ekstrak etanol temu kunci (Boesenbergia pandurata) dan rasio optimal variasi konsentrasi kitosan dan NaTPP dalam pembuatan nanopartikel temu kunci.            Pembuatan ekstrak temu kunci (Boesenbergia pandurata) menggunakan metode maserasi menggunakan etanol teknis 96% dilanjutkan evaporasi hingga terbentuk ekstrak kental temu kunci. Koloid nanopartikel dibuat dengan mencampurkan ekstrak temu kunci dalam etanol p.a, akuades, larutan kitosan dalam asam asetat glasial, dan larutan NaTPP. Ada 9 variasi komposisi antara larutan kitosan dan  NaTPP yakni rasio (5:1); (10:1); (15:1); (20:1); (3,33:1); (8:1); (9:1); (11:1); dan (12:1). Padatan dalam koloid nanopartikel dipisahkan dengan cara sentrifugasi. Endapan yang didapatkan disimpan dalam freezer. Koloid nanopartikel yang terbentuk dikarakterisasi menggunakan Particle Size Analyzer (PSA) dan Zeta Sizeruntuk mengetahui ukuran partikel dan nilai zeta potensial. Padatan yang didapatkan dari proses sentrifugasi selanjutnya dikarakterisasi menggunakan Scanning Electron Microscopy (SEM) untuk mengetahui kondisi morfologi padatan tersebut. Karakterisasi dengan KLT pada padatan yang didapatkan bertujuan untuk mengetahui kesamaan kandungan senyawa antara ekstrak etanol temu kunci dan ekstrak etanol temu kunci dalam sediaan berukuran nano.            Koloid nanopartikel yang telah dibuat berwarna kuning dan setelah di sentrifugasi terbentuk padatan berwarna kuning kecokelatan. Karakterisasi menggunakan PSA menunjukkan ukuran partikel pada rentang 389-877 nm sebanyak 98,1% pada rasio konsentrasi kitosan dan NaTPP = (8:1). Nilai rerata zeta potensial adalah 41,87 mV. Hasil foto SEM menunjukkan morfologi partikel yang memiliki permukaan yang tidak rata. Rf keenam sampel menunjukkan hasil bahwa senyawa yang terkandung dalam ekstrak etanol temu kunci maupun ekstrak etanol temu kunci dalam sediaan nanopartikel adalah sama. Kata Kunci : kitosan, NaTPP, ekstrak etanol temu kunci, KLT, SEM, PSA, zeta sizer

scholarly journals Preparation of ultrafine iron phosphate micro-powder from phosphate slag

2018 ◽  
Vol 238 ◽  
pp. 02002
Author(s):  
Fangjing Sun ◽  
Yi Zhang ◽  
Jiawei Zhang ◽  
Xixi Yan ◽  
Xiaoyu Liu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Particle Size ◽  
Electron Microscope ◽  
Average Particle Size ◽  
Iron Phosphate ◽  
Average Particle ◽  
X Ray ◽  
Particle Size Analyzer ◽  
Phosphate Slag ◽  
Scanning Electron

In this experiment, ultrafine iron phosphate micro-powder was prepared by hydrothermal method which used phosphate slag as an iron source. The effects of reaction temperature, surfactants type and amount on its particle size were explored. The samples were characterized by using Malvern Laser Particle Size Analyzer (MS2000), X-Ray Diffractometer (XRD), Scanning Electron Microscope (SEM) and Energy Dispersive X-Ray Spectroscopy (EDX).The results showed that at 160 °C, 1 wt%CTAB, monoclinic iron phosphate micro-powder was obtained with an average particle size about 0.4 μm which also has a good dispersion in aqueous solution.

On the Lapping Mechanism of Optical Fiber End-Surfaces Using Fixed Diamond Abrasive Films

2011 ◽  
Vol 133 (2) ◽  
Author(s):  
JiAn Duan ◽  
DeFu Liu
Keyword(s):  
Particle Size ◽  
Optical Fiber ◽  
Material Removal ◽  
Abrasive Particle ◽  
Particle Sizes ◽  
Material Removal Mechanisms ◽  
Ductile Mode ◽  
Deformed Layer ◽  
Diamond Abrasive ◽  
Scanning Electron

The purpose of this paper is to reveal material removal mechanisms of optical fiber end-surface in lapping processes. The lapping process experiments are conducted using fixed diamond abrasive lapping films with various particle sizes of 6 μm, 3 μm, 1 μm, and 0.5 μm. The micrographs of the optical fiber end-surfaces are observed using a scanning electron microscope. The experimental results show that there exist three material removal modes in the lapping processes: brittle fracture mode, semibrittle and semiductile mode, and ductile mode. These modes are mainly controlled by abrasive particle size, and there appears a brittle-ductile transition’s critical point when lapping films with a particle size of 3 μm are used to lap optical fiber end-surfaces. An interpretation is proposed for the formation mechanism of the plastic deformed layer on the optical fiber end-surfaces.

Effect of Different Abrasives on Chemical Mechanical Polishing for Magnesia Alumina Spinel

2020 ◽  
Vol 866 ◽  
pp. 115-124
Author(s):  
Zhan Kui Wang ◽  
Ming Hua Pang ◽  
Jian Xiu Su ◽  
Jian Guo Yao
Keyword(s):  
Particle Size ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Chemical Mechanical Polishing ◽  
Removal Rate ◽  
Mechanical Polishing ◽  
Key Factors ◽  
Particle Size Analyzer ◽  
Scanning Electron ◽  
Shape And Size

In this paper, a series of chemical mechanical polishing (CMP) experiments for magnesia alumina (Mg-Al) spinel were carried out with different abrasives, and the materials removal rate (MRR) and surface quality was evaluated to explore their different effects. The scanning electron microscope (SEM) and laser particle size analyzer were also employed to test the micro-shape and size distribution of abrasives. Then, the mechanism of different effects with different abrasives was analyzed in CMP for Mg-Al spinel. Those experimental results suggest that different subjecting pressure ratios of abrasives to polishing pad with different abrasive are the key factors leading to difference polishing performances in CMP.

scholarly journals Ultrastructural Differences Between Thymic and Lymph Node Small Lymphocytes of Mice: Nucleolar Size and Cytoplasmic Volume

Blood ◽  
1967 ◽  
Vol 30 (3) ◽  
pp. 288-300 ◽  
Author(s):  
H. J. HEINIGER ◽  
H. RIEDWYL ◽  
H. GIGER ◽  
B. SORDAT ◽  
H. COTTIER
Keyword(s):  
Lymph Node ◽  
Lymph Nodes ◽  
Frequency Distribution ◽  
Cross Section ◽  
Rna Turnover ◽  
Size Frequency Distribution ◽  
Particle Size Analyzer ◽  
Nucleolar Volume ◽  
The Mean ◽  
Uniform Population

Abstract Ultrastructural differences between small lymphocytes of the thymic cortex and those located in the cortical zone of lymph nodes of mice were examined by electron microscopy and cytometric methods. The particle size analyzer TGZ 3 (Zeiss) was used to measure the size-frequency distribution of nucleolar cross-section diameters, and the resulting data were computed mathematically and statistically to determine the corresponding mean volumina. It could be shown that thymic, as compared to lymph node cortical small lymphocytes, (1) have a smaller mean nucleolar volume (0.11µ3 versus 0.46µ3); (2) represent a more uniform population with regard to the frequency distribution of the nucleolar cross section diameters; and (3) are of smaller size due to less cytoplasm, while the mean nuclear volume does not differ significantly from that of small lymphocytes located in the cortex of lymph nodes. These findings are discussed in relation to qualitative ultrastructural peculiarities and probable differences in the magnitude of RNA turnover as estimated by the use of tritiated cytidine. The possible significance of cytometrically defined populations of small lymphocytes with regard to sensitized and nonsensitized cells is considered.

Preparation and Characterization of Monodisperse Ceria Microspheres

2010 ◽  
Vol 434-435 ◽  
pp. 850-852
Author(s):  
Qi Wang ◽  
Bo Yin ◽  
Zhen Wang ◽  
Gen Li Shen ◽  
Yun Fa Chen
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Particle Size ◽  
Electron Microscope ◽  
Crystalline Form ◽  
X Ray ◽  
Transmission Electron ◽  
Particle Size Analyzer ◽  
Scanning Electron

In present work, ceria microspheres were synthesized by template hydrothermal method. Crystalline form of the as-synthesized ceria microspheres was defined by X-ray powder diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). Dispersibility of ceria microspheres was comprehensively characterized using scanning electron microscope (SEM) observation and laser particle size analyzer. Furthermore, the ultraviolet light absorption performances of ceria microspheres with several different sizes were compared by ultraviolet visible spectrophotometer. The results showed that ceria microspheres presented excellent UV absorbent property and the size influence was remarkable.

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