Nonlinear Microwave Phenomena in Ferrite Films : Basic Physics and Applications (Invited)

There is a wide range of experimental results related to dislocations in diamond, group IV, II-VI, III-V semiconducting compounds, but few of these come from isolated, well-characterized individual dislocations. We are here concerned with only those results obtained in a transmission electron microscope so that the dislocations responsible were individually imaged. The luminescence properties of the dislocations were studied by cathodoluminescence performed at low temperatures (~30K) achieved by liquid helium cooling. Both spectra and monochromatic cathodoluminescence images have been obtained, in some cases as a function of temperature.There are two aspects of this work. One is mainly of technological significance. By understanding the luminescence properties of dislocations in epitaxial structures, future non-destructive evaluation will be enhanced. The second aim is to arrive at a good detailed understanding of the basic physics associated with carrier recombination near dislocations as revealed by local luminescence properties.

Download Full-text

Creating a standard method of controlling digital microscopes: the microscope access protocol (map)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136453 ◽

1995 ◽

Vol 53 ◽

pp. 16-17

Author(s):

T. A. Dodson ◽

E. Völkl ◽

L. F. Allard ◽

T. A. Nolan

Keyword(s):

Data Storage ◽

Storage Systems ◽

Digital Systems ◽

Data Networks ◽

Digital Microscopy ◽

Command Language ◽

Access Protocol ◽

Analog To Digital ◽

Basic Physics ◽

Scanning Electron

The process of moving to a fully digital microscopy laboratory requires changes in instrumentation, computing hardware, computing software, data storage systems, and data networks, as well as in the operating procedures of each facility. Moving from analog to digital systems in the microscopy laboratory is similar to the instrumentation projects being undertaken in many scientific labs. A central problem of any of these projects is to create the best combination of hardware and software to effectively control the parameters of data collection and then to actually acquire data from the instrument. This problem is particularly acute for the microscopist who wishes to "digitize" the operation of a transmission or scanning electron microscope. Although the basic physics of each type of instrument and the type of data (images & spectra) generated by each are very similar, each manufacturer approaches automation differently. The communications interfaces vary as well as the command language used to control the instrument.

Download Full-text

Identifikasi Miskonsepsi dan Tingkat Pemahaman Mahasiswa Tadris Fisika pada Materi Listrik Dinamis Menggunakan 3-Tier Diagnostic Test

Journal of Natural Science and Integration ◽

10.24014/jnsi.v3i2.9911 ◽

2020 ◽

Vol 3 (2) ◽

pp. 128

Author(s):

Lalu A. Didik ◽

Muh. Wahyudi ◽

Muhammad Kafrawi

Keyword(s):

Diagnostic Test ◽

Physics Education ◽

Quantitative Research ◽

Full Understanding ◽

Study Program ◽

Electric Voltage ◽

Quantitative Research Methods ◽

Physics Courses ◽

Basic Physics ◽

Level Of Understanding

This study aims to determine the misconceptions and level of understanding of physics education students on dynamic electricity. The method used is descriptive quantitative research methods. The research sample was 33 students of the tadris physics study program who are currently taking basic physics courses 2 even semester 2019/2020. Data collection used a 3-tier diagnostic test. In the concept of current and electric voltage, students who are included in the full understanding category are 26% and 29% understand partially with the low category and the level of misconception reaches 45%. In the concept of ohm law and electrical resistance, it was found that students with a full understanding level of 23% and partially understanding 14% were in the low category and the level of student misconception showed the largest percentage, namely 63% with the high category. In the concept of electrical circuits, students with a full understanding level of 29% and partially understanding 50% and included in the medium category with student misconceptions showed the smallest percentage was 21% with the low category. As a whole, it shows that the average level of students' understanding and misconceptions on dynamic electricity material is still low with a percentage of 26% and partial understanding is moderate with a percentage of 31% and a misconception of 43% with a moderate category. Keywords: Misconception, level of undertanding, 3-tier diagnostic, electricicity.ABSTRAK.Penelitian ini bertujuan untuk mengetahui miskonsepsi dan tingkat pemahaman mahasiswa tadris fisika pada materi listrik dinamis. Metode yang digunakan adalah metode penelitian deskriptif kuantitatif. Sampel penelitian adalah 33 orang mahasiswa program studi tadris fisika yang sedang menempuh mata kuliah fisika dasar 2 semester genap 2019/2020. Pengumpulan data menggunakan 3-tier diagnostic test. Pada konsep arus dan tegangan listrik, mahasiswa yang termasuk dalam kategori pemahaman penuh sebesar 26% dan paham sebagian sebesar 29% dengan kategori rendah dan tingkat miskonsepsi mencapai 45%. Pada konsep hukum ohm dan hambatan listrik didapatkan bahwa mahasiswa dengan tingkat pemahaman penuh sebesar 23% dan paham sebagian 14% dengan kategori rendah dan tingkat miskonsepsi mahasiswa menunjukkan persentase paling besar yaitu sebesar 63% dengan kategori tinggi. Pada konsep rangkaian listrik, mahasiswa dengan tingkat pemahaman penuh 29%, paham sebagian 50% dengan kategori sedang serta miskonsepsi mahasiswa menunjukkan persentase paling kecil yaitu 21% dengan kategori rendah. Secara kesuluruhan rata-rata tingkat pemahaman dan miskonsepsi mahasiswa pada materi listrik dinamis masih tergolong rendah dengan persentase sebesar 26% dan paham sebagian tergolong sedang dengan persentase 31% dan miskonsepsi sebesar 43% dengan kategori sedang.Kata kunci: miskonsepsi, tingkat pemahaman, 3-tier diagnostic, listrik dinamis

Download Full-text

MicroVolt Variations of The Human Brain (Quantitative Electroencephalography) Display Differential Torque Effects During West-East versus North-South Orientation in the Geomagnetic Field

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v12i2.165 ◽

2016 ◽

Vol 12 (2) ◽

pp. 4255-4259

Author(s):

Michael A Persinger ◽

David A Vares ◽

Paula L Corradini

Keyword(s):

Human Brain ◽

Geomagnetic Field ◽

Neuronal Cell ◽

Single Subject ◽

Additional Energy ◽

Actual Measurement ◽

Neuronal Processes ◽

Basic Physics ◽

Order Of Magnitude ◽

The Moment

Â Â Â Â Â Â Â Â Â The human brain was assumed to be an elliptical electric dipole. Repeated quantitative electroencephalographic measurements over several weeks were completed for a single subject who sat in either a magnetic eastward or magnetic southward direction. The predicted potential difference equivalence for the torque while facing perpendicular (west-to-east) to the northward component of the geomagnetic field (relative to facing south) was 4 Î¼V. The actual measurement was 10 Î¼V. The oscillation frequency around the central equilibrium based upon the summed units of neuronal processes within the cerebral cortices for the moment of inertia was 1 to 2 ms which are the boundaries for the action potential of axons and the latencies for diffusion of neurotransmitters. The calculated additional energy available to each neuron within the human cerebrum during the torque condition was ~10-20 J which is the same order of magnitude as the energy associated with action potentials, resting membrane potentials, and ligand-receptor binding. It is also the basic energy at the level of the neuronal cell membrane that originates from gravitational forces upon a single cell and the local expression of the uniaxial magnetic anisotropic constant for ferritin which occurs in the brain. These results indicate that the more complex electrophysiological functions that are strongly correlated with cognitive and related human properties can be described by basic physics and may respond to specific geomagnetic spatial orientation.

Download Full-text

Basic Physics in Color-Coded EOS Metallization Failures (Differentiating between EOS and ESD)

10.31399/asm.cp.istfa1998p0143 ◽

1998 ◽

Author(s):

Leo G. Henry ◽

J.H. Mazur

Keyword(s):

Failure Analysis ◽

Light Microscope ◽

Structural Changes ◽

Surface Oxide ◽

Aluminum Surface ◽

Surrounding Area ◽

Die Surface ◽

Basic Physics ◽

Direct Contrast ◽

Glass Interface

Abstract The task of differentiating precisely between EOS and ESD failures continues to be a challenging one for Failure Analysis Engineers. Electrical OverStress (EOS) failures on the die surface (burnt/fused metallization) of an IC can be characterized mainly by the discoloration at the site of the failures. This is in direct contrast to the lack of discoloration characteristic of ESD failures, which occur almost exclusively below the die surface (oxide and junction failures). To aid in this distinction, this paper attempts to present the underlying physics behind the discoloration produced in the EOS failures. For the EOS failures, the metal fuses due to the longer pulse widths (sec to msec), while for the ESD failures, the silicon melts because of the shorter pulse widths (< < 500 nsec) and higher energy. After EOS, the aluminum surface becomes dark and rough and the oxide in the surrounding area becomes deformed and distorted, resulting in the discoloration observed in the light microscope. This EOS discoloration could be due to one or more of the following: 1) morphological and structural changes at the metal/glass interface and the glass itself; 2) changes in the thickness and scattering behavior of the glass and metal in the failed areas.

Download Full-text

Abilities of Physics Education Students in Constructing Graphics Based on Practicum Results and in Interpreting It

Jurnal Riset Pendidikan MIPA ◽

10.22487/j25490192.2019.v3.i1.pp35-44 ◽

2020 ◽

Vol 3 (1) ◽

pp. 35-44

Author(s):

Hariawan Hariawan ◽

Muslimin Muslimin ◽

I Komang Werdhiana

Keyword(s):

Physics Education ◽

Research Subjects ◽

Education Students ◽

Study Program ◽

Thinking Aloud ◽

Training And Education ◽

Education Study ◽

Basic Physics ◽

Undergraduate Physics Education ◽

The Relationship

The skills to construct and interpret graphs are a form of science skills and are an important component in learning physics. The purpose of this study was to describe the ability of undergraduate physics education students to construct graphs based on practicum data and interpret them. Data obtained through respondent answer sheets, thinking-aloud recordings, and interviews. The research was conducted at the Faculty of Teacher Training and Education (FKIP) Untad and the research subjects of the Physics Education Study Program students were 6 people obtained based on the values of Basic Physics I and Basic Physics practicum II then divided into three groups of levels (high, medium, and low) with each category as many as 2 people. The results of this study indicate: 1) in general, respondents in the high, medium, and low categories can construct graphs but are not based on the prerequisite ability to construct graphs, especially in determining the x-axis and y-axis variables, 2) on the ability to interpret graphs, respondents can interpret graphs the relationship between variables on the graph but not supported by an explanation or evaluation based on proper physics concepts, 3) The strategy used by respondents in constructing graphs, in general, is to convert data in decimal form or scientific notation and 4) The difficulties experienced by respondents when constructing graphs are converting data, determining the scale and how to determine the variables on each graph axis.

Download Full-text

The Structure and Magnetic Properties of NiZn-Ferrite Films Deposited by Magnetron Sputtering at Room Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.690-693.1702 ◽

2013 ◽

Vol 690-693 ◽

pp. 1702-1706 ◽

Cited By ~ 2

Author(s):

Shuang Jun Nie ◽

Hao Geng ◽

Jun Bao Wang ◽

Lai Sen Wang ◽

Zhen Wei Wang ◽

...

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Magnetron Sputtering ◽

Saturation Magnetization ◽

Room Temperature ◽

Oxygen Flow ◽

Flow Ratio ◽

Study Results ◽

Ferrite Thin Films ◽

Ferrite Films

NiZn-ferrite thin films were deposited onto silicon and glass substrates by radio frequency magnetron sputtering at room temperature. The effects of the relative oxygen flow ratio on the structure and magnetic properties of the thin films were investigated. The study results reveal that the films deposited under higher relative oxygen flow ratio show a better crystallinity. Static magnetic measurement results indicated that the saturation magnetization of the films was greatly affected by the crystallinity, grain dimension, and cation distribution in the NiZn-ferrite films. The NiZn-ferrite thin films with a maximum saturation magnetization of 151 emucm-3, which is about 40% of the bulk NiZn ferrite, was obtained under relative oxygen flow ratio of 60%.

Download Full-text