Scanning-electron-microscope technique for measuring electrical conductivity: Application to tetrathiafulvalene-tetracyanoquinodimethane

The relationship between culture density and the number of microvilli on the cell surface has been studied using BHK21 cells in established monolayer culture. The number of microvilli can be estimated quantitatively by a scanning electron-microscope technique. It can be increased by applying specific antiserum, but whether antibody is applied or not a significant number of cells regularly bear microvilli. This number is characteristic of the culture density. In sparse cultures above a certain minimum density it is relatively high, and in confluent cultures it is much reduced. These results indicate that microvilli may be inhibited by cell contact.

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Blended PVA/PVP Electro spun nanofibers for Coating Application

Journal of Physics Conference Series ◽

10.1088/1742-6596/2114/1/012031 ◽

2021 ◽

Vol 2114 (1) ◽

pp. 012031

Author(s):

R Mohammed ◽

H Jawad ◽

A. Al-Zubiedy

Keyword(s):

Electrical Conductivity ◽

Contact Angle ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Weight Ratio ◽

Polymeric Materials ◽

Vinyl Pyrrolidone ◽

Pumping Rate ◽

Coating Application ◽

Scanning Electron

Abstract The use of polymeric blended nanofibres is one of the recent applications in the food and liquid packaging. The current research aims to prepare the nanofibers coatings from the blend of polymeric materials via the electro spinning technique 0.08 weight ratio concentration of polyvinyl alcohol (PVA) dissolved in water, as well as, (0.2 weight ratio concentration ) of poly vinyl pyrrolidone (PVP) were used to obtain different volume proportions of (PVA:PVP) solutions include (100:0, 80:20,70:30, 50:50, 20:80, and 0:100). The electro spinning system was organized with pumping conditions (20 kV for the applied voltage, 20 cm pumping distance, 1ml/hr pumping rate) and a needle diameter with 0.4mm diameter. The properties of the polymeric solutions involve (viscosity, surface tension, and electrical conductivity of the liquid) were examined. A scanning electron microscope technique was used to study the surface properties of the prepared films, and the contact angle via the contact angle analyzer was examined. The results of a scanning electron microscope proved that the diameter of the nano fibers increases with increasing the concentration and viscosity of solutions and decreasing its electrical conductivity. Also, the results of the contact angle analyzer showed an increase the hydrophilic property via increasing percentage of polyvinylpyrrolidone.

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Karakterisasi Mineral Magnetik Sedimen Sungai Citarum Hilir Melalui Analisa Sifat Magnetik, Mineralogi serta Morfologi Magnetik

POSITRON ◽

10.26418/positron.v10i2.42143 ◽

2020 ◽

Vol 10 (2) ◽

pp. 52

Author(s):

Kartika Hajar Kirana ◽

Mechdi Ghazali ◽

Luh Ayu Eka Safitri Septiana ◽

Dini Fitriani ◽

Eleonora Agustine ◽

...

Keyword(s):

Electrical Conductivity ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Total Dissolve Solid ◽

X Ray ◽

Scanning Electron

Sungai Citarum merupakan sungai utama yang ada di Provinsi Jawa Barat yang sangat penting bagi kehidupan sosial dan ekonomi. Di bagian hilir, Sungai Citarum ini banyak melewati daerah pemukiman padat penduduk, daerah industri, dan bahkan pesawahan. Oleh karena itu, perlu kajian mengenai kondisi Sungai Citarum salah satunya dengan mengidentifikasi parameter electrical conductivity (EC), total dissolve solid (TDS), pH dan suhu serta karakteristik mineral magnetik pada sedimen melalui analisis sifat magnetik, mineralogi dan morfologi magnetiknya. Pengukuran parameter EC, TDS, pH dan suhu dilakukan secara in situ pada sampel air Sungai Citarum, pengukuran sifat magnetik dilakukan pada sampel sedimen yang telah dipreprasi, sedangkan pengukuran mineralogi dan morfologi dilakukan pada sampel sedimen yang telah diekstraksi. Sifat magnetik sedimen diketahui dari nilai suseptibilitas magnetik dual frekuensi yang diukur menggunakan Bartington Magnetik Susceptibilitymeter, sedangkan mineralogi dan morfologi magnetik diketahui berdasarkan hasil pengukuran scanning electron microscope–energy disperdsive x-ray (SEM-EDS) dan x-ray diffractometer (XRD). Hasil pengukuran secara in situ pada sampel air menunjukkan bahwa rentang nilai EC, TDS, pH dan suhu berturut-turut adalah (200–4120) mS/cm, (100–2060) ppt, 7,34–9,22, dan (26,8–32,6) oC. Sedangkan, hasil pengukuran sifat magnetik menunjukkan bahwa sampel sedimen Sungai Citarum bagian hilir memiliki nilai suseptibilitas magnetik frekuensi rendah (cLF) dengan rentang (65,00–173,80) x 10-8 m3/kg, sedangkan rentang nilai suseptibilitas magnetik frekuensi tinggi (cHF) adalah (64,90–165,70) x 10-8 m3/kg. Dari kedua pengukuran cLF dan cHF diperoleh rentang nilai cFD (%) sebesar 0,15–4,66. Selanjutnya, hasil analisis morfologi dari citra SEM-EDS dan analisis mineralogi berdasarkan pengukuran XRD menunjukkan dominasi jenis mineral magnetik pada sampel sedimen adalah magnetit. Mineral magnetit ini memiliki morfologi berbentuk oktahedral sebagai representasi mineral magnetik alami dan ada pula yang berbentuk spherule sebagai representasi mineral magnetik karena adanya proses oksidasi akibat kehadiran material antropogenik pada sedimen Sungai Citarum bagian hilir.

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A Simple Light-Microscope Technique for the Examination of Cell Surfaces

Journal of Cell Science ◽

10.1242/jcs.13.1.317 ◽

1973 ◽

Vol 13 (1) ◽

pp. 317-319

Author(s):

A. ROSS ◽

I. P. GORMLEY

Keyword(s):

Heavy Metal ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Light Microscopy ◽

Light Microscope ◽

Simple Technique ◽

Cell Surfaces ◽

Microscope Technique ◽

Scanning Electron

A simple technique for the examination of cell surfaces by shadowing them with a heavy metal and examining by light microscopy has been described. Stained preparations can be examined and photographed initially prior to investigation by this technique. It is suggested that this technique could be used instead of the scanning electron microscope or replica techniques where the limited resolution of the light microscope is sufficient.

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