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"In this paper ,the growth of GaN:Mn thin films by plasma-assisted metalorganic chemical vapor deposition (PAMOCVD) method is reported ..."

"Pada penelitian ini diamati hasil proses plasma nitriding dan plasma nitrocarburizing pada Baja SKD61 . Dilakukan pre-treatment sebelum dilakukan plasma. Nilai kekerasan optimum yang didapatkan setelah proses pre-treatment sebesar  504 HV. Kekerasan optimum yang didapat pada sampel plasma nitriding yaitu sebesar 603 HV yang dicapai pada temperatur 400^oC dan 500^oC selama 4 jam. Pada plasma nitrocarburizing kekerasan optimum yang didapat yaitu 830 HV dengan temperatur 500^oC selama 4 jam. Hasil ketahanan aus atau specific wear optimum pada sampel plasma nitriding sebesar 0.19 x10^-6mm²/kg yang dicapai pada temperatur 400^oC dan 500^oC selama 4 jam. Pada plasma nitrocarburizing ketahanan aus sebesar 0.11 x10^-6mm²/kg dengan temperatur 400^oC selama 4 jam dan 0.08 x10^-6mm²/kg yang dicapai pada temperatur 500^oC selama 4 jam. Hasil pengujian XRD menunjukan fasa yang terbentuk pada compound layer hasil plasma nitriding yaitu fasa iron nitride berupa FeNx, e-Fe_2-3N dan g’-Fe₄N. Sedangkan fasa yang terbentuk pada compound layer hasil plasma nitrocarburizing yaitu fasa iron nitrid dan juga fasa iron carbonitride FeN, FeN_x, e-Fe_2-3N atau e-Fe_2-3 (N,C) dan Fe₃C. Hasil penelitian yang telah dilakukan menunjukan bahwa plasma nitriding dan plasma nitrocarbuzing berhasil meningkatkan sifat mekanik berupa kekerasan dan ketahanan aus pada baja SKD61.

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This study observed the results of plasma nitriding and plasma nitrocarburizing processes on SKD61 Steel. Pre-treatment was carried out before plasma was performed. The optimum hardness value obtained after the pre-treatment process was 504 HV. The optimum hardness obtained in the plasma nitriding sample is 603 HV with  temperatures of 400^oC and 500^oC for 4 hours. In plasma nitrocarburizing, the optimum hardness obtained is 830 HV at a temperature of 500oC for 4 hours. The optimum wear resistance or specific wear results on plasma nitriding samples are 0.19 x10^-6mm²/kg with temperatures of 400^oC and 500^oC for 4 hours. In plasma nitrocarburizing, the wear resistance is 0.11 x10^-6mm²/kg with temperatures of 400^oC for 4 hours and 0.08 x10^-6mm²/kg with temperature of 500^oC for 4 hours. XRD test results show that the phase formed in the plasma nitriding compound layer is the iron nitride phase in the form of FeNx, e-Fe_2-3N, and g'-Fe4N. Meanwhile, the phases formed in the compound layer resulting from plasma nitrocarburizing are iron nitride, iron carbonitride FeN, FeNx, e-Fe_2-3N, or e-Fe_2-3(N,C) and Fe₃C . The results of the above research on plasma nitriding and plasma nitrocarburizing have improved the mechanical properties of hardness and wear resistance of SKD61 steel."

"Telah dilakukan penelitian yang bertujuan untuk mengetahui pengaruh pemberian fortifikan NaFeEDTA dalam tepung tahu terhadap kadar zat besi plasma darah tikus (Rattus norvegicus L.) jantan galur Sprague- Dawley. Metode penelitian menggunakan Rancangan Acak Lengkap (RAL), terdiri atas 25 ekor tikus putih jantan yang dibagi ke dalam 5 kelompok perlakuan, yaitu KK1 yang diberi larutan CMC 0,5%; KK2 yang diberi CMC 0,5% dan suspensi tepung tahu tanpa fortifikan; dan KP1, KP 2, dan KP3 yang diberi CMC 0,5% dan tepung tahu dengan fortifikan NaFeEDTA dosis 1,35 mg Fe/ kgBB; 2,7 mg Fe/ kg BB; dan 5,4 mg Fe/ kgBB selama 21 hari. Pengambilan darah dilakukan pada hari ke-7, 14, dan 21. Darah ditentukan kadar Fe nya dengan AAS (Atomic Absorption Spectrophotometer). Hasil uji ANAVA satu arah (P < 0,05) menunjukkan pengaruh nyata pemberian fortifikan NaFeEDTA dalam tepung tahu terhadap kadar zat besi antar kelompok perlakuan. Hasil uji LSD (P < 0,05) menunjukkan bahwa terdapat perbedaan kadar zat besi (Fe) dalam darah yang nyata antara KK1 dengan semua kelompok perlakuan (KP1, KP2, dan KP3) dan KK2 dengan semua kelompok perlakuan pada t14. Hasil uji paired-samples T test (P < 0,05) menunjukkan terdapat perbedaan yang nyata kadar zat besi semua kelompok perlakuan pada t14 dan t21. Peningkatan kadar zat besi tertinggi terjadi pada KP3, yaitu sebesar 53,18 % di t14.

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The effect of fortificant NaFeEDTA inserted in tofu flour intake on plasma iron concentration in male Sprague-Dawley rats (Rattus norvegicus L.) has been studied. Twenty five rats were divided into five groups, consist of normal contol group (KK1) which was administered with CMC 0,5%, treatment control group (KK2) which was administered with CMC 0,5% and tofu flour non fortificant, and three treatment groups wich was adminestered with tofu flour added with fortificant NaFeEDTA 1,35 mg Fe/kgbw (KP1); 2,7 mg Fe/kgbw (KP2); and 5,4 mg Fe/kgbw (KP3). All of the five groups were treated for 21 consecutive days. The plasma iron concentration was measured by Atomic Absorption Spectrophotometer (AAS). One way ANAVA test ( P < 0,05) showed significant effect of fortificant NaFeEDTA inserted in tofu flour intake on plasma iron concentration in all treatment groups. LSD test (P<0,05) showed that the plasma iron concentration significantly different between KK1 towards all treatment groups and KK2 towards all treatment groups. Paired-samples T Test (P < 0,05) showed that the plasma iron concentration significantly different in all treatment groups on t14 and t­21. The higest increase of plasma iron concentration was detected on KP3 at t14, whic is 53,18 %."

"High velocity oxy-fuel (HVOF) sprayed tungsten carbide ? cobalt (WC-Co) coatings exhibit attributes that allow them to be a candidate material for high temperature applications; such as temperature insulators for rocket nozzles. This application note investigates the effect of surface preparation, in this case the grit blasting process, on the characteristics of the so-formed coating. The WC-Co coatings exhibited high hardness and low porosity. The composition of WC-Co coating varied in different regions, but on average was close to the composition of the initial feedstock, implying that there was no preferential loss of the material during the spray process.Microanalysis indicated diffusion of tungsten to the interface between the coating and the substrate and partly explains the high bonding strength of the coating. These physical characteristics suggest that the HVOF sprayed WC-Co is an appropriate coating technology for rocket nozzles."

"ABSTRACTOzon merupakan oksidator kuat, sehingga efektif digunakan untuk membunuh bakteri, virus, dan jamur. Karena ozon dapat berjalan tanpa membentuk produk-produk samping di air, banyak proses industri yang memanfaatkan ozon. Walaupun demikian, pemanfaatan ozon di Indonesia belum diaplikasikan secara maksimal oleh masyarakat, karena alasan besarnya biaya ozonator komersial serta umur penggunaan yang singkat atau mudah rusak, juga terutama karena ozon hanya dapat bertahan beberapa menit sebelum terdekomposisi menjadi oksigen kembali. Dalam penelitian ini dilakukan rancang-bangun pengembangan reaktor plasma DBD dielectric barrier discharge dengan model pelat sejajar konfigurasi paralel untuk pembangkitan ozon pada suhu ruang. Setelah diuji kinerjanya menggunakan metode titrasi iodometri, diperoleh produksi ozon serta konsumsi energinya pada kondisi operasi optimal yang mampu mendekati atau bahkan melebihi produktivitas ozon model-model sebelumnya, yaitu mencapai 0,82 gr ozon/jam dengan konsumsi energi 42,06 kWh/kg umpan udara dan 6,45 gr ozon/jam dengan konsumsi energi 7,62 kWh/kg umpan oksigen murni . p.p1 margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica Neue color: 454545

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ABSTRACTOzone is a powerful oxidizer, so it is effectively used to kill bacteria, viruses, and fungi. Because ozone can run without forming by products in the water, many industrial processes utilize ozone. Nevertheless, ozone utilization in Indonesia has not been applied maximally, due to the large cost of commercial ozonators and short life or easily damaged, since ozone can only last a few minutes before decomposing into oxygen again. In this research, a plasma DBD dielectric barrier discharge reactor models with parallel plates for ozone generation at room temperature were designed and developed. After the productivity of the ozonators were tested with iodometric titration method, the ozonator rsquo s productivity in generating ozone and its energy consumption with the optimum operating condition were obtained and are able to compete or even exceeds the productivity of the previous ozonator models. The ozonator can produce up to 0,82 gr ozone hour with 42,06 kWh kg compressed air feed and 6,45 gr ozone hour with 7,62 kWh kg energy consumption pure oxygen feed . p.p1 margin 0.0px 0.0px 0.0px 0. 0px text align justify font 12.0px Helvetica Neue color 454545."

"In recent developments in the area of thermofluid technologies, active flow control has emerged as an interesting topic of research. One of the latest methods, which will be discussed in this paper, is the application of a plasma actuator. Plasma actuation is achieved by conducting a high-voltage electric current through an actuator device. Our research was specifically conducted to discover its effect on the reduction of the drag coefficient, with Ahmed Body the experimental object put inside a suction-flow wind tunnel with varying inputs of flow velocity. The plasma actuator device was run with an A.C. power supply and installed in three different placement configurations on the aerodynamic model to determine which most optimally affected the aerodynamic drag, while the drag coefficients were acquired via the use of a load cell installed as the harness for the aerodynamic model inside the tunnel. The results of the experiments include that the optimal configuration of the actuator placement was on the leading edge, the optimal wind flow velocity of the experiment, which was essential for the actuation to be observed, was at 1.7 m/s, and the resulting drag reduction percentage, as a result of induced flow, was 22% of the initial drag coefficient."

"Kejadian infeksi dengue dewasa di Indonesia tergolong tinggi. Komplikasinya adalah sindrom renjatan dengue (SRD) akibat kebocoran plasma. Untuk mengatasi kebocoran plasma, WHO menganjurkan pemberian cairan kristaloid isotonik atau koloid seperti albumin 5%. Penelitian in vitro memperlihatkan ikatan albumin dengan reseptor glikoprotein 60 (gp60) di sel endotel menstimulasi ekspresi caveolin-1 dan Src protein tyrosine kinase (PTK) yang meningkatkan perpindahan albumin ke ekstravaskular, namun secara in vivo belum diketahui pengaruh cairan albumin terhadap proses transitosis dan caveolin-1 urin.Penelitian ini merupakan open label randomized controlled trial sejak bulan November 2018 sampai dengan Januari 2020, di beberapa rumah sakit di Jakarta dan Banten. Dari 90 pasien, sebanyak 30 pasien memenuhi kriteria DD, dan 60 pasien memenuhi kriteria DBD. Alokasi secara acak dilakukan pada 60 pasien DBD, yang terdiri atas kelompok demam berdarah dengue yang diberikan ringer laktat (n = 30) dan kelompok demam berdarah dengue yang diberikan albumin (n = 30).Pasien DBD yang diberikan albumin 5%, caveolin-1 plasma menurun pada jam ke-12 (p = 0,016); Src PTK lebih rendah pada jam ke-12 (p = 0,048); hemokonsentrasi lebih ringan pada jam ke-12 (p = 0,022) dan ke-24 (p = 0,001); kadar albumin serum lebih tinggi pada jam ke-12 (p = 0,037) dan ke-24 (p = 0,001); albumin urin lebih ringan pada jam ke-24 (p = 0,006) dan ke-48 (p = 0,005); dan lama rawat lebih pendek (p < 0,001) dibandingkan dengan ringer laktat.Kesimpulan: pemberian cairan albumin 5% memperbaiki kebocoran plasma transitosis dan memperpendek lama rawat pasien DBD.

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The incidence of adult dengue infection in Indonesia is quite high. The complication is dengue shock syndrome (DSS) due to plasma leakage. To overcome plasma leakage, WHO recommends giving isotonic crystalloid solutions or colloids such as albumin 5%. In vitro studies have shown that albumin binding to the glycoprotein receptor 60 (gp60) in endothelial cells stimulates the expression of caveolin-1 and Src protein tyrosine kinase (PTK) which increases albumin transfer to the extravascular space, but in vivo the effect of albumin fluid on the process of transitosis and urine caveolin-1 is not known.

This study is an open label randomized controlled trial from November 2018 to January 2020, in several hospitals in Jakarta and Banten. From 90 patients, 30 patients met the criteria for DD, and 60 patients met the criteria for DHF. Random allocation was made to 60 DHF patients, consisting of the dengue hemorrhagic fever group given Ringer's lactate (n = 30) and the dengue hemorrhagic fever group given albumin (n = 30).

Patients who were given albumin 5%, caveolin-1 plasma decreased at 12th hours (p = 0.016); Src PTK was lower at 12 hours (p = 0.048); milder hemoconcentration at 12th (p = 0.022) and 24th (p = 0.001) hour; serum albumin levels were higher at 12th (p = 0.037) and 24 hours (p = 0.001); urinary albumin was milder at 24th (p = 0.006) and 48th (p = 0.005); and shorter length of stay (p < 0.001) compared to ringer lactate.

Conclusion: administration of albumin 5% fluid improves transcytosis plasma leakage and shortens the length of stay of dengue infection patients."

"This study was designed to optimalize the use of opididymal or ejaculate sperm and plasma for in vitro fertilization,that sperm agglutination was found at preparation. The rate of sperm agglutination was calculated the head-to-head sperm agglutination that were incubated in KR-HEPES medium in 38.5 oC with 5% CO2 at 1,3,5 and 7 hours culture in vitro....."

"Magnesium dikenal sebagai logam struktural ringan yang ideal untuk aplikasi biomaterial karena sifatnya yang biokompatibel dan biodegradabel. Namun, tantangan utamanya adalah kecenderungan korosi yang cepat dalam kondisi fisiologis. Metode PEO telah banyak digunakan untuk meningkatkan ketahanan korosi, dengan teknik yang memungkinkan pembentukan lapisan oksida yang padat dan tahan lama. Penelitian ini bertujuan untuk menganalisis pengaruh penambahan hidroksiapatit (HA) 1 g/L dan 10 g/L dan penggunaan arus berselang dalam proses Plasma Electrolytic Oxidation (PEO) terhadap sifat elektrokimia, bioaktivitas, dan karakteristik lapisan pada paduan magnesium AZ31. Arus berselang artinya penghentian arus selama 1 menit setelah arus diaplikasikan selama 4 menit, yang diulangi hingga tiga kali. Pengujian korosi dilakukan menggunakan metode Electrochemical Impedance Spectroscopy (EIS) dan Potentiodynamic Polarization (PDP), serta pengujian bioaktivitas menggunakan larutan Simulated Body Fluid (SBF). Penambahan hidroksiapatit (HA) dan penerapan arus berselang dalam proses PEO telah dilakukan pada paduan AZ31 untuk meningkatkan ketahanan korosi dan bioaktivitas. Pada konsentrasi HA 10 g/L, diperoleh nilai RpEIS sebesar 1,89 × 10⁵ Ω·cm² dan RpPDP sebesar 6,15 × 10⁸ Ω·cm². Senyawa kalsium-fosfat (Ca-P) terbentuk dengan rasio Ca/P antara 0,17–0,23. Setelah 14 hari perendaman dalam SBF, seluruh sampel menunjukkan degradasi. Hasil ini menunjukkan bahwa kombinasi metode tersebut dapat meningkatkan performa permukaan, meskipun diperlukan evaluasi lebih lanjut terhadap ketahanan jangka panjang.

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This study investigates the impact of hydroxyapatite (HA) addition and anodic pauses during the Plasma Electrolytic Oxidation (PEO) process on the corrosion resistance and bioactivity of AZ31 magnesium alloy. The alloy, known for its biodegradability and biocompatibility, suffers from rapid corrosion in physiological environments. To address this, the PEO process was modified by adding HA at concentrations of 0, 1, and 10 g/L, and introducing intermittent pauses in current application to the PEO electrolyte solution and implemented a 1-minute pause after 4 minutes of current application. Testing was conducted using Electrochemical Impedance Spectroscopy (EIS) and Potentiodynamic Polarization (PDP) methods to evaluate electrochemical properties, while bioactivity testing was carried out using Simulated Body Fluid (SBF) solution to assess corrosion resistance. The addition of hydroxyapatite (HA) and the application of anodic pauses in the PEO process have been proven to enhance the corrosion resistance and bioactivity of the oxide layer on AZ31 alloy. Hydroxyapatite (HA) addition and pulsed current PEO were applied to AZ31 alloy to improve corrosion resistance and bioactivity. At 10 g/L HA, RpEIS and RpPDP reached 1,89 × 10⁵ Ω·cm² and 6.15 × 10⁸ Ω·cm², respectively. Ca-P formed with a Ca/P ratio of 0.17–0.23. All samples showed degradation after 14 days in SBF. The method enhanced surface properties but requires further long-term assessment."