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"This paper reports on the magnetic properties and electromagnetic characterization of La0.8Ba0.2FexMn½(1-x)Ti½(1-x)O3 (x = 0.1–0.8). The La0.8Ba0.2FexMn½(1-x)Ti½(1-x)O3 (x = 0.1–0.8) materials were prepared using a mechanical alloying method. All the materials were made of analytical grade precursors of BaCO3, Fe2O3, MnCO3, TiO2, and La2O3, which were blended and mechanically milled in a planetary ball mill for 10h. The milled powders were compacted and subsequently sintered at 1000°C for 5h. All the sintered samples showed a fully crystalline structure, as confirmed using an X-ray diffractometer. It is shown that all samples consisted of LaMnO3 based as the major phase with the highest mass fraction up to 99% found in samples with x < 0.3. The mass fraction of main phase in doped samples decreased in samples with x > 0.3. The hysteresis loop derived from magnetic properties measurement confirmed the present of hard magnetic BaFe12O19 phase in all La0.8Ba0.2FexMn½(1-x)Ti½(1-x)O3 (x = 0.1–0.8) samples. The results of the electromagnetic wave absorption indicated that there were three absorption peaks of ~9 dB, ~8 dB, and ~23.5 dB, respectively, at respective frequencies of 9.9 GHz, 12.0 GHz, and 14.1 GHz. After calculations of reflection loss formula, the electromagnetic wave absorption was found to reach 95% at the highest peak frequency of 14.1 GHz with a sample thickness of around 1.5 mm. Thus, this study successfully synthesized a single phase of La0.8Ba0.2FexMn½(1-x)Ti½(1-x)O3 (x = 0.1–0.8) for the electromagnetic waves absorber material application."

"Beberapa dekade terakhir ini peredam gelombang elektromagnetik (microwave absorber) dari bahan magnetik telah banyak digunakan untuk aplikasi di bidang pertahanan militer, elektronik dan telekomunikasi. Secara sederhana dapat dikatakan bahwa bahan absorber gelombang elektromagnetik adalah sebuah bahan yang dapat melemahkan energi gelombang elektromagnetik. Bahan-bahan yang memiliki kriteria sebagai bahan absorber gelombang elektromagnetik adalah bahan harus memiliki karakteristik permeabilitas (magnetic loss properties) dan permitivitas (dielectric loss properties). Kandidat potensial sebagai bahan absorber gelombang elektromagnetik adalah bahan magnetik sistem ABO3 perovskite lanthanum manganite. Dengan rekayasa struktur sistem lanthanum manganite ini diharapkan dapat menjadi bahan unggul untuk aplikasi microwave absorber. Pengembangan bahan magnetik yang dilakukan dalam penelitian ini mencakup sistem La(1-y)BayFexMn½(1-x)Ti½(1-x)O3 (x = 0 - 1,0 dan y = 0 - 1,0) telah diperoleh komposisi yang paling baik yaitu komposisi senyawa La0.8Ba0.2Fe0.3Mn0.35Ti0.35O3. Sintesis nanopartikel senyawa La0.8Ba0.2Fe0.3Mn0.35Ti0.35O3 fase tunggal telah berhasil diperoleh melalui metode pemaduan mekanik dilanjutkan dengan tahapan sintering pada suhu 1000 °C selama 10 jam. Sintered materials kemudian dihaluskan kembali selama 20 jam. Hasil refinement pola difraksi sinar-x menunjukkan bahwa senyawa La0.8Ba0.2Fe0.3Mn0.35Ti0.35O3 memiliki struktur monoklinik dengan parameter kisi a = 5,5182(8) Å, b = 5,5442(8) Å, c = 7,822(1) Å, dan  = 89,63(1)o. Ukuran rata-rata kristalit partikel senyawa La0.8Ba0.2Fe0.3Mn0.35Ti0.35O3 adalah 42 nm. Sedangkan ukuran rata-rata partikelnya berdasarkan pengujian dengan Particle Size Analyser adalah 72 nm. Material bersifat ferromagnetik memiliki karakteristik nilai permeabilitas dan permitivitas yang baik. Hasil pengujian serapan gelombang elektromagnetik pada rentang frekuensi 9 - 15 GHz menunjukkan bahwa terdapat tiga frekuensi puncak serapan pada frekuensi 9,9 GHz, 12,0 GHz, dan 14,1 GHz dengan nilai reflection loss berturut-turut sebesar ~ 9 dB, ~ 13 dB, dan ~ 25 dB. Disimpulkan bahwa bahan sistem La(1-y)BayFexMn½(1-x)Ti½(1-x)O3 (dengan x = 0 - 1,0 dan y = 0 - 1,0) menjadi kandidat yang potensial untuk digunakan sebagai bahan unggul absorber gelombang elektromagnetik.

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Recently electromagnetic wave absorber materials haves been used for military, electronic, and telecommunication devices. In a very simple definition, electromagnetic wave absorber material is a material that can weaken the electromagnetic wave energy. Basic properties which are required of electromagnetic wave absorber materials were that the materials must have high permeability (magnetic loss properties) and high permittivity (dielectric loss properties) values. One of potential candidates for absorbing materials is ABO3 perovskite lanthanum manganite-based system. Structurals modification of the basic lanthanum manganite was applied in order to find the best the microwave absorber characteristics of the modified materials system. Current research activities were covering La(1-y)BayFexMn½(1-x)Ti½(1-x)O3 (x = 0 - 1.0 and y = 0 - 1.0) compositions. It was found that the best composition with an improve microwave absorption characteristic is La0.8Ba0.2Fe0.3Mn0.35Ti0.35O3. Single phase of La0.8Ba0.2Fe0.3Mn0.35Ti0.35O3 nanoparticles were successfully synthesized by mechanical alloying method. The mixture of all precursors were first mechanically milled for 10 hrs and then sintered at a temperature of 1000 °C for 10 hrs in which a fully crystalline material is ensured. The sintered material was then re-milled for 20 hrs to obtain powder-based nanoparticles. The refinement of x-ray diffraction trace for re-milled materials confirmed a single phase material with a monoclinic structure of lattice parameters: a = 5.5182(8) Å, b = 5.5442(8) Å, c = 7.822(1) Å, and  = 89.63(1)o. The mechanically alloyed and sintered materials in the whole mechanical milling resulted in powders with mean crystallite size 42 nm. The mean particle size as refering to the particle size analyzer was 72 nm in the second mechanically milled powders. Thus, results of mean crystallite size and crystallite size evaluations for the powder materials showed that the mean crystallite zise is almost similar to the mean particle size. In addition, the hysteresis curve evaluation showed that the sample material is ferromagnetic. Results of VNA evaluation indicated that there were three of absorption peaks with reflection loss values ~ -9.0 dB, ~ -11.5 dB, and ~ -25.0 dB at frequency 9.9 GHz, 12.0 GHz, and 14.1 GHz respectively. The study concluded that the magnetic materials of La(1-y)BayFexMn½(1-x)Ti½(1-x)O3 compositions (x = 0 - 1,0 and y = 0 - 1) have a good potential to be a candidate of electromagnetc wave absorbing materials."

"Series of Ti2+-Mn4+ ions substituted BaFe12-2xTixMnxO19 samples with x = 0.0–0.8 have been studied to find out the effect of ion substitution on their microstructure, magnetic, and microwave absorption characteristics. The materials were synthesized through the mechanical alloying process. X-ray diffraction pattern for all sintered samples confirmed that the materials are single phase materials with BaFe12O19 structure. Referring to the results, it is shown that all samples that are subject to ultrasonic irradiation treatment characterized by a crystallite size distribution with the width get slimmer and mean crystallite size get smaller as the substitution level increased from x = 0 to x = 0.8. A sample of latter composition has fine crystals between 10–200 nm with the mean size of 42 nm. The effect of ionic substitution also affected the magnetic properties in which coercivity decreased proportionally with an increase of x value. The saturation magnetization increased to 0.41 T at x = 0.4, and then decreased for higher x values. Hence, the increase occurred only in samples with low-level substitutions of Ti2+-Mn4+ ions. Microwave absorption characterization clearly shows that the reflection loss (RL) value of Ti2+-Mn4+ substituted BaFe12-2xTixMnxO19 samples was enhanced from 2.5 dB in a doped free sample (x = 0) to 22 dB (~92% absorption) in a sample with x = 0.6 in the frequency range 8–12 GHz."

"Pengolahan data magnetik menghasilkan nilai magentik total yang telah dikoreksi oleh koreksi IGRF, Variasi Harian dan Koreksi Drift. Hasil pengolahan data kemudian diplot menjadi kontur anomali magnetik pada software SURFER 9.0. Dari kontur inilah kemudian didapatkan indikasi anomali magnetik pada data pengukuran. Anomali inilah yang nantinya akan dijadikan patokan untuk membuat permodelan. Permodelan menggunakan data magnetik bertujuan untuk mengidentifikasikan anomali magnetik yang terdapat pada data pengukuran. Anomali magnetik biasanya dipengaruhi oleh hot rock yang berada pada bawah permukaan. Pada penelitian ini, data magnetik yang digunakan adalah data pengukuran magnetik di daerah Arjuna-Welirang. Daerah prospek geothermal Arjuna-Welirang terletak di wilayah Kabupaten Malang, Kabupaten Mojokerto, Pasuruan, dan Kota Batu. Daerah prospek ini berada di lingkungan geologi yang didominasi oleh batuan vulkanik berumur kuarter.

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Magnetic data processing give a magnetic total value that has been corrected by the correction IGRF, Diurnal Variety and Drift Correction. Then the data processing?s results are plotted into the contours of the magnetic anomalies in the software Surfer 9.0. This contour is then obtained an indication of magnetic anomalies on the measurement data. This is an anomaly that will be used as a benchmark for modeling. Modeling using magnetic data aims to identify magnetic anomalies are present in the measurement data. Magnetic anomalies are usually influenced by the hot rock that is on the bottom surface. In this study, which used magnetic data is the data of magnetic measurements in the Arjuna-Welirang. Geothermal prospect area Arjuna-Welirang located in Malang regency, regency Mojokerto, Pasuruan, and Batu. This prospect area is located in the geological environment which is dominated by old volcanic rocks quarter."

"Pertumbuhan butir pada temperatur 1100oC, 1200oC, dan 1300oCkristal LaxBa(1-x)Fe0.25Mn0.5Ti0.25O3 dipelajari. Material sampel dipreparasi menggunakan teknik pengaloyan mekanik (mechanical alloying) dengan waktu penggilingan (high ball energy milling) selama 30 jam. Sintering dilakukan selama 0, 1, 3 dan 6 jam. Material dianalisa menggunakan sinar X. Besar ukuran butir dihitung menggunakan persamaan Debye-Scherrer berdasarkan profil difraksi sinar X-nya. Sifat magnetik diukur menggunakan pemagraf. Sedangkan serapan gelombang mikro diukur menggunakan alat Network Analyzer (VNA) dengan metode Transmission/Reflection Line (TRL). Semua pengukuran dilakukan pada temperatur kamar. Hasil penelitian menunjukkan bahwa persamaan pertumbuhan butir kristal La0.25Ba0.75Fe0.25Mn0.5Ti0.25O3 mengikuti model persamaan laju difusi. Hasil serapan gelombang mikro menunjukkan adanya serapan pada frekuensi 11-15 GHz. Serapan ini relatif lebih kecil jika dibandingkan dengan serapan material basisnya yakni LaFe0.25Mn0.5Ti0.25O3. Namun daerah serapannya relatif lebih luas daripada material basis tersebut.

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Growth of La0.25Ba0.75Fe0.25Mn0.5Ti0.25O3 in the temperatur e1100oC, 1200oC, dan 1300oC during 0, 1, 3 and 6 hours sinteringwas investigated. Sampels was prepared by mechanical alloying techique with high ball energy milling. Milling time is 30 hours. Sample was analized using x-ray diffraction.Grain size was calculated using Debye-Scherrer equation based on their x-ray diffraction profiles. Material absorbance properties was measured using Network Analyzer (VNA) with Transmission/ Reflection Line (TRL) measurement technique. All analysis was conducted in room temperature.

Data showed that grain growth of La0.25Ba0.75Fe0.25Mn0.5Ti0.25O3 has followed diffusion rate equation model of. Whilst it microwave absorbance measurement data performed its wide absorbance in the fequency range 11-15 GHz. Despite its relatively small absorbance intensity, La0.25Ba0.75Fe0.25Mn0.5Ti0.25O3 has broader bandwith comparing to its base material LaFe0.25Mn0.5Ti0.25O3."

"Telah dilakukan penelitian tentang studi sifat listrik dan optis bahan perovskite Ba(Fe,Ti)O3. Pada studi ini kami menguji sifat material multiferroik lewat difraksi sinar X dan spektroskopi impedansi. Hasil difraksi sinar X (XRD) menunjukkan bahan memiliki fasa tunggal dengan sistem kristal heksagonal dan space group P63/mmc. Struktur kristal Ba(Fe,Ti)O3 menjadi random perovskite ketika sampel dibuat dengan komposisi Fe dan Ti yang seimbang, sehingga mempengaruhi seluruh sifat bahan BaFe0,5Ti0,5O3. Pengukuran impedansi yang dinyatakan dalam bentuk Nyquist plot dan bode plot memperlihatkan bahwa penambahan Fe menyebabkan peningkatan konduktivitas ac dan melemahkan feroelektrisitas. Fitting rangkaian ekivalen dengan program Zsimpwin menunjukkan kemunculan induktansi (L) dan Constant Phase element (CPE) sebagai akibat penambahan ion magnetik Fe dan dispersi frekuensi pada sampel. Data hasil pengukuran reflektansi dengan menggunakan spektrofotometer UV VIS menunjukkan nilai celah energi berada dalam rentang 0,85 - 3,37 eV yang membuat bahan berpotensi menjadi semikonduktor.

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We have been investigating Study of electrical and Optical Properties Sample Perovskite Ba(Fe,Ti)O3. In this study, we have systematically measured the multiferroic material properties using XRD and impedance simulation. The result of X-ray diffraction (XRD) indicates that the material has a single phase with hexagonal crystal and space group P63/mmc. Random perovskite structure is shaped when the sample made with balanced composition between Fe and Ti and thus affecting the whole nature of the material BaFe0, 5Ti0,5O3. Impedance measurements which are signed in form of nyquist and bode plot show that the addition of Fe leds to an increase of ac conductivity and weakend ferroelectricity. Fitting the equivalent circuit with Zsimpwin program pilots the appearance of inductance (L) and constant phase element (CPE) as a result of adding magnetic Fe ions and frequency dispersion of the sample. Reflectance measurement data using a UV VIS spectrophotometer showed the value of the energy gap is in the range 0.85 to 3.37 eV which could potentially be a semiconductor."

"This book is both a course book and a monograph. The first chapter briefly introduces the history, background and technology of EPM. In the second chapter, the concept of transport phenomena is concisely introduced and in the third chapter the essential part of magnetohydrodynamics is transcribed and readers are shown that the concept of transport phenomena does not only apply to heat, mass and momentum, but also magnetic field. The fourth chapter describes electromagnetic processing of electrically conductive materials such as electromagnetic levitation, mixing, brake, and etc., which are caused by the Lorentz force. The fifth chapter treats magnetic processing of organic and non-organic materials such as magnetic levitation, crystal orientation, structural alignment and etc., which are induced by the magnetization force. This part is a new academic field named magneto-science, which focuses on the development of super-conducting magnets."

"RAM (Radar Absorbing Material) merupakan sebuah bahan yang dapat menyerap dan melemahkan gelombang elektromagnetik. Dalam satu dekade terakhir, RAM banyak menggunakan bahan berbasis Barium Hexaferrite karena sifat-sifatnya yang memiliki magnetisasi saturasi (Ms), medan koersivitas (Hc), medan anisotropi (Ha) dan konstanta anisotropi (K) yang besar, dan frekuensi resonansi yang tinggi. Sifat-sifat dasar tersebut berkaitan erat dengan sifat serapan gelombang elektromagnetik. Pada penelitian ini dilakukan rekayasa mikrostruktur dan struktur sel senyawa barium hexaferrite (BaFe12O19) dengan komposisi BaFe(12-x)Sn0,5xZn0,5xO19 ( x= 0,0 - 1,0) dan komposisi BaFe(11,65-x)Sn0,35ZnxO19 (x=0,0, 0,05, 0,1, dan 0,15) pada perubahan struktur parameter kristal, sifat magnetik, dan pengaruhnya terhadap sifat serapan gelombang elektromagnetik dalam jangkau frekuensi RADAR. Penyiapan sampel dilakukan melalui reaksi pemaduan basah secara mekanik (mechanical alloying). X-ray diffraction (XRD), scanning electron microscope (SEM), permagraph, dan vector network analyzer (VNA) masing-masing digunakan untuk mengamati dan menganalisis fasa dan struktur kristal, morfologi permukaan, sifat-sifat magnetik, dan serapan gelombang elektromagnetik. Material fasa tunggal BaFe(12-x)Sn0,5xZn0,5xO19 diperoleh pada komposisi x ≤ 0.35 memiliki grain seragam terdistribusi secara acak dengan ukuran rata-rata grain meningkat dari 126 nm pada komposisi x = 0,05 sampai 154 nm pada komposisi x = 0,35 sedangkan pada komposisi x > 0,35 menurun secara drastis hingga 71 nm pada komposisi x = 1,0. Sifat-sifat magnetik Ms, Hc, Ha, dan K1 menurun dengan pertambahan kandungan x dalam sampel. Sementara, sifat serapan gelombang elekromagnetik meningkat dengan bandwidth yang lebar karena penurunan Hc. Serapan maksimum terjadi pada komposisi x = 0,35 dengan reflection loss (RL) sebesar - 28,09 dB (menyerap 96,06 % intensitas gelombang yang datang) pada frekuensi 9,92 GHz dan bandwidth 3,10 GHz. Optimalisasi penyerapan gelombang RADAR ditelusuri pada material dengan komposisi BaFe(11,65-x)Sn0,35ZnxO19 (x= 0,0, 0,05, 0,1, dan 0,15). Fasa tunggal terjadi pada semua komposisi dengan struktur mikro terdiri dari grain terdistribusi secara random. Ukuran rata-rata grain adalah 91 nm pada x= 0,0 mengalami sedikit peningkatan sampai 142 nm pada x= 0,15. Optimalisasi penyerapan gelombang RADAR pada material BaFe(11,65- x)Sn0,35ZnxO19 terjadi pada pada komposisi x= 0,05 dengan RL sebesar -36,39 dB (menyerap 98,48 % intensitas gelombang yang datang) pada frekuensi 9,96 GHz dengan bandwidth 2,74 GHz. Terjadi peningkatan nilai RL sebesar 2,42 % dibandingkan dengan penyerapan optimal material penyerap BaFe(12-x)Sn0,5xZn0,5xO19 komposisi x= 0,35. Peningkatan ini disertai dengan penurunan bandwidth sebesar 11,61 %. Hasil penelusuran efek ukuran partikel terhadap optimalisasi penyerapan memperlihatkan semakin kecil dan seragam ukuran partikel, semakin besar penyerapan intensitas gelombang elektromagnetik disertai dengan pergeseran frekuensi puncak serapan ke frekuensi yang lebih rendah dan bandwidth yang semakin sempit.Maksimum RL diperoleh pada material dengan komposisi BaFe11,6Sn0,35Zn0,05O19 berukuran rata-rata partikel 400 mesh -53,45 dB atau menyerap 99,79 % intensitas gelombang yang datang pada frekuensi 9,42 GHz, bandwidth 0,4 GHz. Kesimpulan umum dari hasil penelitian ini adalah substitusi ion Sn4+ dan Zn2+ terhadap ion Fe3+ pada senyawa BaFe12O19 efektif menurunkan koersivitas dan mempertahankan magnetisasi remanen. Nilai RL material penyerap komposisi BaFe11,6Sn0,35Zn0,05O19 mencapai 98,48 % (- 36,39 dB) dengan bandwidth 2,74 GHz dalam jangkau frekuensi Radar (x-band). Peningkatan lanjut nilai RL mencapai 99,79 % (-53,45 dB) dapat diperoleh dengan mengecilkan ukuran ratarata partikel lolos saringan 400 mesh disertai konsekuensi penurunan bandwidth sebesar 85,40 %.

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Radar Absorbing Material (RAM) is material capable of absorbing and reducing electromagnetic waves. Over the last decade, most RAM has been made from materials based on barium hexaferrites due to its properties which have high values of saturation magnetization (Ms), coercivity (Hc), anisotropic field (Ha), magnetocrystalline anisotropic constant (K1), and a high natural resonance frequency. These properties are closely related to the absorption properties of electromagnetic waves. In this study, the modification of barium hexaferrite (BaFe12O19) to BaFe(12-x)Sn0,5xZn0,5xO19 ( x= 0.0 - 1.0) and BaFe(11,65-x)Sn0,35ZnxO19 (x= 0.0, 0.05, 0.1, and 0.15) compositions was performed, which led to changes in crystal structure parameters, magnetic properties and their effect on electromagnetic wave absorption properties within the RADAR frequency range. The samples were prepared via a wet mechanical alloying reaction. X-ray diffraction (XRD), scanning electron microscope (SEM), permagraph and vector network analyser (VNA) were used to observe and analyse phases, crystal morphology, magnetic properties and absorption of electromagnetic wave, respectively. The single-phase material BaFe(12-x)Sn0,5xZn0,5xO19 obtained at composition x = 0.35. The microstructure consisted of uniform grains whose orientation was random and the mean size of the grains changed from 126 nm at composition x= 0.05 to 154 nm at composition x= 0.35. While at composition x > 0,35 it decreased dramatically to 71 nm at composition x = 1,0. The magnetic properties of Ms, Hc, Ha, and K1 decreased with increasing x content in the sample. Meanwhile, the absorption properties of electromagnetic waves increase with a large bandwidth as a result of a decrease in Hc. The maximum absorption occured in the x= 0.35 composition with a reflection loss (RL) of -28,09 dB (absorb 96.06% of the incoming wave intensity) at a frequency of 9.92 GHz and a bandwidth of 3.10 GHz. The optimization of the absorption of RADAR waves has been traced to the composite materials BaFe(11.65-x)Sn0.35ZnxO19 (x= 0.0, 0.05, 0.1 and 0.15). Single-phase materials were obtained in all compositions with a microstructure composed of randomly oriented grains. The mean grain size is 91 nm at x = 0.0, rising slightly to 142 nm at x = 0.15. Optimization of RADAR wave absorption on BaFe(11.65-x)Sn0.35ZnxO19 material occurs at composition x= 0,05, resulted in RL of -36.39 dB (absorbs 98.48% of the incoming wavelength) at a frequency of 9.96 GHz with a bandwidth of 2.74 GHz. The RL value increased by 2.42% compared to the optimum absorption of BaFe(12-x)Sn0.5xZn0.5xO19 at x= 0.35. The increase was accompanied by 11.61 % decrease in bandwidth. The effect of particle size on absorption shows that the smaller and more uniform the particle size, the greater the absorption of magnetic waves. The increase in absorption was accompanied by a shift in the absorption peak frequency to a lower frequency and narrower bandwidth. The largest RL was obtained from material with a composition of BaFe11.6Sn0.35Zn0.05O19, with the mean particle size of 400 mesh (37 μm). This resulted in RL of -53.45 dB or absorbing 99.79% of incoming wave intensity at a frequency of 9.42 GHz and a bandwidth of 0.4 GHz. The general conclusion from the results of this study is that the substitution of Sn4+ and Zn2+ ions on Fe3+ ions in BaFe12O19 compounds is effective in reducing coercivity, and maintaining remanent magnetization. BaFe11.6Sn0.35Zn0.05O19 has reached 98.48% (-36.39 dB) with a bandwidth of 2.74 GHz in the radar (x-band) frequency range. In addition, an increase in RL to 99.79% (-53.45 dB) was achieved by reducing the mean particle size through a 400 mesh filter with a substantial decrease in bandwidth of 85.40%."

"Dislipidemia menyebabkan abnormalitas pada lemak darah seperti peningkatan Low-Density Lipoprotein Cholesterol (LDL-c). Pajanan SMF berpengaruh pada membran untuk memodulasi jumlah Ca2+ intraseluler melalui jalur calmodulin sehingga mempengaruhi ekspresi gen yang memodulasi degradasi LDL-c. Protein Sterol-regulatory element-binding protein-2 (SREBP-2) merupakan protein yang berperan dalam regulasi kolesterol dan sebagai faktor transkripsi dari gen Low Density Lipoprotein Receptor (LDLR) untuk berikatan dengan LDL-c yang ada di plasma darah, sehingga berkaitan dengan kadar LDL-c. Tujuan peneitian ini melihat efek pajanan SMF dengan Bmax=2mT selama 1 jam/hari dalam mempengaruhi efek biologis sel sehingga mempengaruhi kadar kalsium, Ekspresi SREBP-2 dan LDLR. Mencit C57BL/6J jantan dibagi menjadi kelompok pakan normal dan High Fat Diet (HFD). Kelompok HFD dibagi menjadi kelompok Obes (0,2,7,14,dan21) berdasarkan hari pajanan. Kemudian diambil plasma untuk untuk melihat Kolesterol dan LDL-c dan organ hati untuk analisis kalsium dan ekspresi SREBP-2 dan LDLR. Terdapat perubahan kadar kolesterol dan LDL-c pada plasma darah secara signifikan P<0.05 dan cenderung mengalami peningkatan kadar kalsium, ekspresi LDLR, dan SREBP-2, pada kelompok pajan dibandingkan dengan kontrol P>0.05. Oleh karena itu, pajanan SMF berpengaruh terhadap kadar total kolesterol dan LDL-c pada sirkulasi darah serta mempengaruhi kadar kalsium, ekspresi protein SREBP-2, dan ekspresi gen LDLR. Efek pajanan SMF terhadap total kolesterol, LDL-c, kadar kalsium, ekspresi SREBP-2 dan LDLR. Bergantug pada lama pajanan, dimana pada penelitian ini lama pajanan optimal adalah 7 har

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Dyslipidemia causes abnormalities in blood lipids, such as an increase in Low-Density Lipoprotein Cholesterol (LDL-c). SMF exposure affects the membrane to modulate the amount of intracellular Ca2+ through the calmodulin pathway, thereby affecting the expression of genes that modulate LDL-c degradation. Protein Sterol-regulatory element-binding protein-2 (SREBP-2) is a protein that plays a role in cholesterol regulation. As a transcription factor of the Low-Density Lipoprotein Receptor (LDLR) gene binds to LDL-c in blood plasma, it is related to LDL-c levels. This study aimed to look at the effect of exposure to SMF with Bmax=2mT for 1 hour/day in influencing the biological effects of cells, thereby affecting calcium levels, SREBP-2, and LDLR expression. Male C57BL/6J mice were divided into standard and high-fat diet (HFD) groups. The HFD group was divided into obese groups (0,2,7,14, and 21) based on the day of exposure. Then plasma was taken to see Cholesterol and LDL-c and liver for calcium analysis and SREBP-2 and LDLR expression. There were significant changes in blood plasma cholesterol and LDL-c levels P<0.05 and tended to have increased calcium levels, LDLR expression, and SREBP-2 in the exposure group compared to controls P>0.05. Therefore, SMF exposure affects total cholesterol and LDL-c levels in the blood circulation and affects calcium levels, SREBP-2 protein expression, and LDLR gene expression. Effect of SMF exposure on total cholesterol, LDL-c, calcium levels, SREBP-2, and LDLR expression. Depending on the length of exposure, in this study, the optimal exposure time was 7 days."