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"We report the effects of a transverse magnetic field (J⊥B) on the conductivity of quantum well tunneling structures based on AlGaAs/GaAs/AlGaAs quantum wells. The current voltage characteristics in the positive differential resistance regime show negative magnetoconductance for all values of B. The peak bias voltage increases monotonically with increasing B. For B≪6 T there is a decrease in the peak tunneling current, but then it increases for B≫6 T. The data also show dramatic magnetic field induced changes in the negative differential resistance (NDR) features. The behavior of the NDR changes from sharp hysteretic bistable like transitions to astable NDR transitions. Both the valley current and its bias voltage position increase with increasing magnetic field. This behavior is described by a simple model that includes magnetic field effects across the barriers."

"Magnetic field effect on CaCO3 precipitation is the key parameter in evaluating the effectiveness of Anti-scale Magnetic Treatment (AMT). The purpose of this study was to investigate magnetic fields influence on CaCO3 precipitation in high and low super-saturated CaCO3 solution by varied pH CaCO3 solution using circulation flow fluid system. The observation results in the high super saturated solution (pH 8.5) showed the increase of precipited CaCO3 in magnetized solutions compared to those in non-magnetic solution during circulation process. In the low super-saturated CaCO3 solution (pH 6.4) it was found that magnetic treatment increased CaCO3 precipitation after circulation process. In high super-saturated solution, magnetic field strengthens ion interactions, which reduce precipitation during circulation process. However, in low super-saturated CaCO3 solution, magnetic field weakens hydrate ion interaction which indicated by decreasing of the conductivity of solution. It increases the precipitation of CaCO3 after the circulation of magnetization process has completed."

"Hard water causes the CaCO3 scale formation on the pipe walls and heat exchanger equipments in industrial or domestic water processes. A great number of experimental researches on the prevention of the CaCO3 precipitation process by magnetic field have been carried out. In this research, Na2CO3 and CaCl2 solutions was magnetized in the circulated flow condition (dynamic fluid system). The velocity of fluid and the circulation time was modified to examine its influences to the magnetization process. CaCO3 content was measured by titration method of EDTA complexometry. Conductivity test was conducted to find out hydrate ion bonding.

The results showed that magnetization increased the CaCO3 formation and the optimum process reaches for 10 minutes circulation on 0.554 m/s of flow rate. Magnetic field decreases the conductivities of Na2CO3 and CaCl2 solution, hence reduced the ion hydrate bonding. These results showed that magnetization on Na2CO3 and CaCl2 ionic solution was effective in controlling the CaCO3 formation by increasing CaCO3 precipitation."

"Single Emissive Organic Light Emitting Diode (OLED) merupakan divais diodapenghasil cahaya yang terdiri dari emissive layer yang diapit oleh 2 konduktoryakni anoda dan katoda. OLED dibuat dengan proses fabrikasi yang direalisasikandengan berbagai tahapan, pada skripsi ini dilakukan tahapan fabrikasi. Ketikalaminasi dilakukan, temperatur laminasi menjadi masalah dalam proses fabrikasiyang menentukan berhasil atau tidaknya fabrikasi divais dioda. Pada skripsi inidilakukan fabrikasi OLED struktur ITO/PFO/Al dengan temperatur laminasi yangberbeda-beda. Setelah fabrikasi, dilakukan pengujian karakteristik I-V dari divaisOLED. Hasil pengujian karakteristik I-V menunjukkan bahwa laminasi optimalterjadi pada temperatur 160 C.

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Single Emissive Organic Light Emitting Diode OLED is a diode device composedof emissive layer sandwiched by 2 conductors that are anode and cathode. OLED ismade by fabrication process that is realized by many steps, in this paper laminationstep was performed. While lamination, the lamination temperature become one ofthe problems in fabrication process that decided the diode fabrication is success ornot. In this paper OLED with ITO PFO Al structure was fabricated with differentlamination temperature. Then, I V characteristic of OLED device was tested. TheI V characteristic test result show that the optimum lamination is at temperature160 C."

"Transfer daya nirkabel merupakan sebuah cara baru untuk mengatasi ketidaknyamanan dari sumber listrik dengan kabel. Salah satu cara untuk menyuplai listrik tanpa kabel yaitu menggunakan resonansi kopling elektromagnetik. Cara ini dapat menyuplai listrik ke beban karena adanya medan magnet dan medan listrik di sekitar alat transfer daya nirkabel tersebut. Jadi, perlu diketahui karakteristik medan magnet dan medan listrik dari antena pengirim dan penerima yang akan digunakan pada alat tersebut dan hasilnya apabila dibandingkan dengan standar paparan elektromagnetik. Pada tulisan ini, tiga model antena loop dianalisis yaitu antena berongga, antena pejal, dan antena mikrostrip. Beberapa parameter disimulasikan dengan perangkat lunak berbasis finite integration technique (FIT) yaitu intensitas medan magnet(H-field), medan magnet(B-field), dan intensitas medan listrik(E-field). Hasil simulasi menunjukkan bahwa antena mikrostrip menghasilkan nilai tertinggi pada ketiga parameter yang dianalisis yaitu H-field, B-field, and E-field. Hasil distribusi medan untuk tipe antena yang lain, antena berongga dan pejal, lebih kecil dari pada yang dihasilkan oleh antena mikrostrip. Berdasarkan standar paparan elektromagnetik dari ICNIRP dan IEEE, nilai medan magnet dan medan listrik alat transfer daya nirkabel hasil simulasi masih dibawah standar.Sedangkan pada penerapannya untuk teknologi ruang angkasa, desain dan pengukuran pada jarak 5 mm belum sesuai untuk teknologi ruang angkasa.

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Wireless power transfer is a new way to break inconvenience of wiring power sources. The best way how to supply electric power through wireless system is using the electromagnetic coupled resonance phenomena. It can supply electric power to the load because of the magnetic and electric field that emerge around wireless power transfer device. So, we need to know the characteristic of magnetic and electric field from transmitter and receiver that will be used for the device and see the results based on electromagnetic exposure standard. In this study, three loop model of antennas are investigated, namely a solid coil model, hollow coil model, and microstrip coil model. Some parameters of those models are numerically analyzed using the finite integration technique (FIT) such as magnetic field intensity (H-field), magnetic field (B-field), and electric field intensity (E-field).

The final result shows that microstrip antenna has the highest score in H-field, B-field, and E-field. The field distribution of the others, those are solid coil and hollow coil, are relatively less than that the microstip coil has.Based on electromagnetic exposure like ICNIRP and IEEE, magnetic and electric field of wireless power transfer device are below the standards. Meanwhile, for space aircraft applications, this kind of design and simulation which are measured on 5 mm is unappropriate for space aircraft technology."

"Diajukan sebuah model yang menjelaskan mekanisme pembentukan gerak pada protein berdasarkan interaksi-interaksi materi dengan pendekatan lagrangian. Sumber non-linier yang disuntikan direpresentasikan oleh lagrangian medan elektromagnetik. Pelipatan protein terjadi karena sumber nonlinier merambat melalui badan protein. Perambatan sumber non-linier melalui badan protein, dapat membuat transisi protein dari bentuk metastabil ke keadaan dasar.

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A model to describe the mechanism of conformational dynamics in protein based on matter interactions using lagrangian approach is proposed. Nonlinear sources injected are represented by electromagnetic feld lagrangian. Protein folding is caused by nonlinear source propagate through the protein backbone. Propagation of nonlinear source through the bakcbobe of the protein, can mediate the transition of a protein from metastable conformation to its ground state."

"The magnetic susceptibility and high magnetic ESR measurement of SrCu2(PO4)2 has been performed at temperaturesranging from 4.2 K to 300 K and 4.2 K to 77 K, respectively. The magnetic susceptibility shows a broad maximumaround T = 40 K. The magnetic susceptibility has been interpreted in terms of one-dimensional magnetic systems. Thetemperature dependence of the magnetic susceptibility indicated a good agreement with 4-spin alternating configurationmodel. In the ESR measurement, clear electron spin resonance (ESR) was observed. The integrated intensity for 120 and301 GHz has a broad maximum at around 40 K, which is consistent with the susceptibility result. A quantitativedescription gives resonance is the first and second triplet excited states of the excitation spectrum of 4-spin alternatingchain configuration. The g1, g2 and g3 values are approximately 2.21 at temperature above 40 K. The g2 dan g3 valueshave the dependence of temperature under 40 K."

"Aluminium merupakan salah satu logam yang memiliki sifat mekanik yang baik. Aplikasi aluminium pada piston dalam mesin menyebabkan aluminium mengalami gesekan sehingga dapat terjadinya keausan sebelum waktunya karena karakteristik tribologi aluminium yang kurang baik. Aluminium dapat dipadukan dan dilapisi salah satunya menggunakan kobalt yang memiliki ketahanan korosi dan ketahanan aus untuk memperbaiki kekurangan dari aluminium. Pelapisan dilakukan dengan menggunakan metode elektrodeposisi karena mudah dan hemat biaya. Penambahan medan magnet selama elektrodeposisi dapat menjadi parameter yang dapat diamati pengaruhnya. Medan magnet yang diberikan secara tegak lurus terhadap katoda dapat menyebabkan adanya aliran magnetohydrodynamic yang didasarkan pada gaya Lorentz sehingga menyebabkan adanya peningkatan pada proses elektrodeposisi. Lapisan hasil elektrodeposisi dengan pengaruh medan magnet diamati menggunakan XRD didapatkan pengaruh medan magnet pada ukuran kristal yang terbentuk. Mikrostruktur lapisan yang terbentuk diamati menggunakan mikroskop optik dengan pengaruh medan magnet menyebabkan adanya perubahan pada lapisan yang terbentuk dan pengujian sifat korosi menggunakan metode linear sweep voltammetry didapatkan hasil laju korosi yang paling efektif terdapat pada sampel yang diberikan pengaruh medan magnet.

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Aluminum is a metal that has good mechanical properties. The application of aluminum to the piston in the engine causes the aluminum to experience friction so that it can prematurely wear because of the unfavorable tribological characteristics of aluminum. Aluminum can be combined and coated, one of which uses cobalt which has corrosion resistance and wear resistance to increase aluminium properties. Coating is carried out using the electrodeposition method because it is easy and cost-effective. The addition of a magnetic field during electrodeposition can be a parameter where the effect can be observed. The magnetic field applied perpendicular to the cathode can cause a magnetohydrodynamic flow based on the Lorentz force, causing an increase in the electrodeposition process. The electrodeposition result layer with the influence of a magnetic field was observed using XRD. It was obtained the effect of the magnetic field on the size of the crystals formed. The microstructure of the layer formed was observed using an optical microscope with the influence of a magnetic field causing changes in the formed layer and testing the corrosion properties using the linear sweep voltammetry method, the most effective corrosion rate results were found in samples subjected to magnetic fields."

"Organic Light-Emitting Diode OLED merupakan LED yang memiliki lapisan organik pada bagian emisifnya untuk memancarkan cahaya ketika dialiri arus listrik. Meskipun teknologi pencahayaan dan display OLED sudah berkembang, efisiensi OLED secara umum masih rendah sehingga dibutuhkan penelitian dan eksperimen yang dapat meningkatkan performa OLED baik dari segi struktur maupun materialnya.Skripsi ini akan membahas pengaruh jenis material anoda dan katoda terhadap efisiensi daya melalui proses simulasi dengan software SimOLED 4.5.1. Struktur yang disimulasikan adalah single emissive layer OLED dengan Alq3 sebagai material organiknya. Selain itu, juga akan dilakukan proses fabrikasi menggunakan teknik laminasi dan spin-coat. Fabrikasi bertujuan untuk menganalisis material katoda yang menghasilkan karakterisasi I-V paling optimal.Hasil dari simulasi pada SimOLED membuktikan bahwa kombinasi material PEDOT:PSS dan alumunium Al memiliki nilai efisiensi daya sebesar 1000 kali lebih tinggi dibanding struktur referensi ITO ndash; Lif-Al . Kemudian pada proses fabrikasi, material katoda yang menghasilkan performa paling baik adalah Al dengan PFO sebagai lapisan emisif dan ITO sebagai anoda. Hasil OLED yang difabrikasi menghasilkan arus tertinggi sebesar 2 10-8 A pada 10 Volt.

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Organic Light Emitting Diode OLED is an LED that has an organic layer on its emissive layer to emit light when electrified. Although OLED lighting and display technologies have evolved, OLED efficiency is generally low. Therefore, research and experiments are required so that OLED performance can be improved from both its structure and material.

This thesis will discuss the effect of anode and cathode material on power efficiency through simulation process using SimOLED 4.5.1 software. The simulated structure is a single emissive layer OLED with Alq3 as its organic material. In addition, fabrication process will also be done using lamination and spin coat techniques. Fabrication aims to analyze the cathode material that produces the most optimum I V characterization.

Simulation results show that the combination of PEDOT PSS and aluminum as the electrode material has a power efficiency value of 1000 times higher than reference structure which is ITO and Lif Al. Then in the fabrication process, the cathode material that produces the best performance is aluminum, with PFO as emissive material and ITO as anode. OLED results in fabrication has a maximum current of 2 10 8 at 10 Volts."