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Ovarian malignant tumors are the fifth leading cause of death from malignant tumors and have the highest mortality rate among uterine malignant tumors in the United States. Factors associated with an increased risk of ovarian cancer include age, nulliparity, and a family history of cancer. The aim of this study was to determine the profile ovarian tumor in anatomical pathological Dr. Soetomo General Academic Hospital during 1 January 2016 – 31 December 2020. This study used a descriptive observational study with a retrospective approach. The data were presented in tables of the distribution of the number of cases, age and histopathological diagnosis. The data was obtained from the electronic medic record (EMR) of Dr. Soetomo General Academic Hospital. There were 1107 cases, the most age was 41-50 years, namely 285 cases (25.75%), mucinous carcinoma was the most histopathological of malignant tumor, namely 145 cases (24.75%), mucinous borderline tumour was the most histopathological of borderline tumor, namely 34 cases (85%) and endometriosis was the most histopathological of benign tumor.

The objectives of this study are to investigate the influence of concentration variation of potassium hydroxide (KOH) and to remove a heavy metal in liquid waste of the activated carbon. The raw material of activated carbon was obtained from pineapple crown waste. Pineapple crowns pre-carbonized at 180 oC for 1 hour. Chemical activation was carried out using KOH with concentration 2M, 3M, and 4M for 20 hours at 30 oC and temperature 60 oC for 2 hours. Microwave irradiation was conducted at 630 Watt of output power for 15 minutes. The physical properties of activated carbon were characterized using scanning electron microscopy to determine surface morphology of activated carbon, X-ray diffraction to calculated microstructure (i.e. interlayer spacing and microcrystalline dimension) using Bragg’s and Scherer’s equations, specific surface area was calculated from N2 adsorption-desorption isotherm using BET equation, Fourier-transform infrared (FTIR) identify the functional groups of activated carbon, and heavy metals absorption was tested using atomic adsorption spectrophotometric. The highest surface area of activated carbon is 300,901 m2/g for activated carbon with concentration 2M corresponding to the highest stack height (Lc) of activated carbon of 10,470 nm. The carbon chain structure shows the functional groups C-H, C≡C, O-H, C-OH, and CH2 at wavenumbers of 2889,49 cm-1, 2360,97 cm-1, 2339,97 cm-1, and 998,21 cm-1, respectively.

Since March 2020 the spread of the Corona virus has hit almost all parts of the world. The number of victims is increasing while a cure has not yet been found. The angry community then began to take the initiative to save themselves and their families by buying medical devices such as masks, handsanitizers to APD (Personal Protective Equipment) clothes or better known as Hazmat shirts. Unfortunately, the price of these three materials has increased many times over, naughty parties play by piling up goods and then throwing them into the market at an unreasonable price. Do not lose their mind, people rack their brains to take advantage of new business opportunities in the Covid-19 era, including making and mixing their own handsanitizers, sewing masks and of course hazmat suits. The scarcity of these items actually affects the performance of medical personnel. This dedication is made in order to help empower UMKM in Pekanbaru City to try to read the market and produce their hazmat suits themselves. As a result, with the intense competition and the lack of public interest in sewing Hazmat clothes, the service team managed to embrace UMKM that manage their own convection, even though they are on a small scale.

Wabah Covid-19 yang melanda dunia telah membuat pola hidup berubah. Masyarakat dituntut menjaga jarak sosial, membatasi aktivitas di luar rumah dan menerapkan pola hidup bersih dan sehat. Sisi lain yang menarik untuk dilihat dari pandemi ini adalah tingginya jiwa sosial masyarakat, dibuktikan dengan membantu pihak yang terdampak covid baik kesehatan maupun ekonomi. Salah satu bentuk kepedulian masyarakat adalah membuat dan menyumbangkan masker dan baju hazmat bagi para tenaga medis. Universitas Riau melalui tim Pengabdian kepada Masyarakat (PKM) Covid mencoba memenuhi kebutuhan tersebut melalui pendampingan usaha mikro, kecil, dan menengah (UMKM) di Kota Pekanbaru. Sulitnya menemukan bahan baku pembuatan baju hazmat menyebabkan tim pengabdian harus membeli bahan baku dari luar Pulau Sumatra. Selain itu hanya ada dua UMKM yang bersedia menjahit baju hazmat. Total baju hazmat yang dibuat sebanyak 120 pieces dan telah didistribusikan ke tujuh lokasi di kota Pekanbaru dan sekitarnya.

The electrical and optical properties of nanomaterials depend on their structural form. As an effort to develop an advanced nanomaterial, zinc oxide (ZnO) is interesting to synthesis for many applications such as active material for solar cells and biosensors. This paper provides the role of palladium and plasmonic materials in growing ZnO nanostructure, with a focus on its structural analysis. Nanomaterial ZnO was grown by seed-mediated hydrothermal method with layering by plasmonic materials, i.e. gold (Au) and platinum (Ag). X-ray diffraction analysis shows the presence of three dominant peak angles, i.e 34.43o, 36.32o, and 47.49o corresponding to crystal orientation of (002), (101) and (102), respectively. Palladium (Pd) treatment plus layering by plasmonic materials give a higher size of the nanostructure, but their electric band gaps are decreasing slightly. These findings also supported by high absorbance in UV-vis spectra. Gold layering on the nanomaterial gives a more significant role than platinum which indicated by higher size in diameter and higher absorption of UV-Vis spectra. The average size of pristine ZnO, ZnO:Pd, ZnO:Pd:Ag, and ZnO:Pd:Ag are 44.13, 45.99, 45.28, and 44.81 nm, respectively.

Charge-transfer and photoactivity at an interface of a photoactive materials, such as ZnO, is critically influence the performance of dye-sensitized solar cell (DSSCs). The performance of DSSCs utilizing Au decorated ZnO nanorod photoanode with Au nanoparticles grown at seven different growth times from 0.12 up to 6 min were studied. It was found that the charge transfer characteristic of DSSCs devices utilizing Au decorated ZnO nanorods increased with the increasing of Au nanoparticles size and density and optimum at Au nanoparticles size of ca. 15 nm and density of approximately 4–10 nanoparticles/nanorods. At this condition, the charge transfer resistance as low as 7.4 Ω was recorded. This is equivalent to power conversion efficiency of 1.11%. The charge transfer resistance gradually declined when the growth time further elongated. The efficient charge transfer can be associated to the excellent catalytic properties of Au nanoparticles on ZnO nanorods. This also improves its carrier transport in the device as judged from significantly low dark current properties. The improvement of light absorption can also be considered to improve the performance, attributed to the surface plasmon resonance (SPR) effect of the gold nanoparticles. The preparation of Au nanoparticles decorated ZnO nanorods and the mechanism of charge transfer characteristics will be discussed.

Ternary cobalt-based metal oxide (ZnCo2O4) has been successfully coated onto aluminum substrate via sol–gel method. The coatings were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) and UV–Vis–NIR spectrophotometry. Thermal degradation of the coatings was probed by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Model of crystal growth kinetics and density functional theory (DFT) calculations further probed the crystalline structure evolution. The predicted ZnCo2O4 crystalline structures were confirmed by XRD and EDX. The grain growth kinetic model for ZnCo2O4, derived from Lifshitz–Slyozov–Wagner (LSW) theory, determined that the growth of crystalline phases is unaffected by the annealing temperature; however, the crystallites’ sizes decreased with the increase in precursor concentration. DFT analysis indicated that structural energy stability between the bulk state and slabs of ZnCo2O4 was at two oxygen layers (O-layers) with an optimum grain width of 17.21 A. Interestingly, the morphology of ZnCo2O4 represented a rose-like template structure formed by inter-connecting layers of nanosheets. This unique surface morphology enhanced the optical absorptance properties up to α = 70.7%.

The addition of metal dopant into ZnO nanocrystals may induce changes both electronic and crystal grow properties, which later modify its photoactivity and surface physico-chemistry properties, improving its photovoltaic performance in DSSCs application. Here we report a dramatic distortion in the crystal grow orientation of ZnO in the presence of ruthenium ion dopant, changing the crystal morphology from fine hexagonal shape nanorod to starfruit-like shape nanorod. We found that such modification in the ZnO nanostructure enhanced photovoltaic properties, in typical case increased up to two times increment to 0.43%, compared to pristine hexagonal nanorod sample (0.2%). The present results may provide alternative strategy to augment the photoactivity of the nanostructure. High performance DSSC device will then be obtained when optimized fabrication procedure is implemented.

Magnetite (Fe3O4) nanoparticles are very promising to be applied as a drug delivery system (DDS) for cancer chemotherapy. In this research, the crystal growth of hydrothermal derived magnetite particles was studied by oriented attachment (OA) model. The OA model was used to investigate the mechanism and the statistical kinetic of crystal growth. The crystal diameter change as a function of time with different concentration was measured using XRD. Firstly, 0.3248 g FeCl3 and 1.1764 g of sodium citrate, as well as 0.3604 g urea were dissolved into 40 mL of distilled water in a reactor. Subsequently, the reactor temperature was maintained at 210 °C and reaction time of 3.5–12 h in an air oven. The morphology of obtained particles was characterized using TEM, whereas VSM was used to determine the magnetic hysteresis curve. The XRD pattern showed that magnetite was obtained at temperature 210 °C and 3.5 h reaction time, as well as its intensity increased with reaction time. The crystal size of Fe3O4 was 9.44 nm at 3.5 h and appropriate with the oriented attachment model. The magnetite nanoparticles with shaped core-shell size less than 50 nm and suitable for biomedical application especially as drug delivery.

Sensor arus eddy (eddy current) digunakan untuk pengukuran ketebalan logam khususnya logam non magnetik seperti alumunium. Penelitian ini telah mengembangkan sensor eddy current berbahan PCB (printed circuit board) jenis FR4 yang memiliki ketebalan lapisan tembaga 35micron. Prototipe yang dihasilkan mempergunakan koil sensor dengan jumlah gulungan (n) 30 lilitan, diameter (Æ) 30mm, lebar dan jarak antar koil, (dkoil) 0,254mm dan tahanan (Rkoil) sebesar 4,26Ω. Respon sensor ketebalan pelat logam terhadap bahan uji dievaluasi dengan memberikan eksitasi frekuensi tunggal 700Khz, 1MHz dan 1.33MHz. Rangkaian ketebalan pelat telah mempergunakan rangkaian pengunci fasa (phase locked loop) dan mampu mengukur variasi ketebalan mulai 0,2 mm sampai 2 mm, sementara jarak antara sensor dengan logam uji dijaga konstan 2 mm. Hasil pengukuran memberikan respon kurva U(t) dalam hubungan Kata-kata kunci:sensor eddy current, PCB FR4, material non magnetik, ketebalan logam, rangkaian phase locked loop Abstract Eddy current sensor is used to measure the thickness of metals, especially non-magnetic metals such as aluminum. This research has developed eddy current sensor made from PCB (printed circuit board) type FR4 which has 35micron copper layer thickness. The developed prototype uses a designed coil sensor with the number of winding (n) 30 turn, diameter () 30mm, width and distance between coils, (dkoil) 0.254 mm and coil resistance (Rkoil) of 4.26 Ω. The sensor response to the test material was evaluated by giving a single frequency excitation of 700 Khz, 1 MHz and 1.33 MHz. The plate thickness electronics has used a phase locked loop circuit and is capable to measure the thickness variations from 0.2 mm up to 2 mm, while the distance between the sensor coil and the test object was kept constant at 2 mm. The measurement results give the U (t) curve response in the exponential relationship. Keywords: eddy current sensor, PCB FR4, nonmagnetic material, thickness, phase locked loop circuit

Dye sensitized solar cell (DSSC) is made with a layer arrangement of fluorine tin oxide (FTO), zinc oxide (ZnO), dye, electrolyte, and plastisol. ZnO nanorods which play a role as photoanode in DSSC have been successfully grown on FTO substrate using seed mediated hydrothermal method at temperature of 90 oC for 8 hours. Modification was made to increases the efficiency of DSSC by adding silver (Ag) with concentration of 5 mM into dye molecules. ZnO characterization was performed using ultra violet-vissible (UV-Vis) spectroscopy and field emission scanning electron microscopy (FESEM). The strongest UV-Vis absorbance spectrum with the optimum absorbance for the ZnO sampel was occurred at the wavelength range of 300 – 360 nm. Meanwhile, for the ZnO sample with addition of 5 mM Ag into dye molecule was occurred at the wavelength range of 440 – 530 nm. FESEM image of the sample shows the as-synthesized ZnO nanorods have hexagonal cross section. I-V characteristics in the light mode was carried out to determine the efficiency of DSSC using a halogen lamp with an intensity of 100 mW/cm 2 . The efficiency of DSSC using ZnO with addition of 5 mM Ag into dye molecule is 0.462%, increases compared to the efficiency of DSSC using ZnO without addition of Ag into dye molecule which only produce 0.45% efficiency. These results indicate that the addition of Ag can increase the efficiency of DSSC.

Chemical activation with assisted microwave irradiation was used to produced activated carbon from orange peel waste. The activating agent was potassium hydroxide (KOH) with concentrations of 2 M, 3 M, and 4 M. The microwave irradiation was done for 15 minutes with a 630 Watt output power. KOH concentration affected the physical properties of OP-ACxM. With increasing KOH concentration, the interlayer spacing (d002 and d100 ) grew, stack height (Lc ) increased, and stack width (La) dropped. The number of pores on the surface of OP-ACxM increased after the chemical activation process. In OP-ACxM, FTIR analysis reveals the presence of O-H, C-H, C-C, C=O, C=C, and C-O.

Telah dilakukan analisa dimensi, densitas dan kapasitansi spesifik pada pembuatan elektroda karbon superkapasitor dari bunga rumput gajah menggunakan variasi konsentrasi aktivator KOH. Pembuatan elektroda karbon diawali dengan proses prakarbonisasi, penggilingan dengan ball milling dan diayak dengan ukuran partikel < 53 µm. Proses berikutnya dilakukan aktivasi kimia menggunakan aktivator KOH dengan variasi konsentrasi sebesar 0,3 M, 0,5 M dan 0,7 M. Pelet karbon dibuat dengan alat hydraulic press pada tekanan 8 ton. Proses karbonisasi dilakukan pada suhu 600°C pada lingkungan gas N 2 dengan profil pemanasan bertingkat, dan diikuti dengan proses aktivasi fisika menggunakan gas CO 2 pada suhu 850°C . Hasil penelitian ini diperoleh bahwa diameter, ketebalan dan massa setiap elektroda superkapasitor mengalami penurunan seiring dengan peningkatan konsentrasi KOH. Sedangkan densitas dan kapasitansi spesifik mengalami peningkatan dengan pertambahan konsentrasi KOH. Nilai kapasitansi spesifik tertinggi diperoleh sebesar 100,62 F/g dengan densitas 0,87 gr/cm 3 pada variasi 0,7 M KOH. Kata-kata kunci: Analisa Dimensi, Kapasitansi Spesifik, Superkapasitor, Bunga Rumput Gajah, Variasi KOH Abstract Dimensions, density and specific capacitance of carbon electrode supercapacitor from flower of elephant grass by using various KOH concentrations has been analyzed. Production of carbon electrodes was performed by pre-carbonization, grinding by ball milling and sieving to a find a particle size of < 53 µm. The following process was an activation by chemical activation using KOH by various concentrations of 0.3 M, 0.5 M and 0.7 M. Carbon pellets were produced by hydraulic press instrument at a pressure of 8 tons. Carbonization process was carried out at a temperature of 600°C in a N 2 gas environment with multilevel heating profile, and followed by physical activation process by throwing CO 2 gas at a temperature of 850°C. The results of this study showed that the diameter, thickness and mass of each carbon electrode supercapacitor decrease with the increasing of KOH concentrations. While the density and specific capacitance were increased with the increasing of KOH concentrations. The highest specific capacitance value was obtained as high as 100.62 F/g with a density of 0.87 g/cm 3 in the variation of 0.7 M KOH. Keywords : Dimensional Analysis, Specific Capacitance, Supercapacitors, Flower Elephant Grass, Variations KOH

Synthesis parameter plays important role in modifying physical property of metal oxide films which serve as photoanode in dye-sensitized solar cell (DSSC). This paper reports the synthesis of boron doped ZnO nanostructures via seed mediated growth hydrothermal technique and their application as photanode in DSSC. The growth process was carried out at various solution concentrations, 0.1, 0.2, 0.3 and 0.4 M. The solution contains 1 % wt. dimethyl borate as boron source, hexamethylenetetramine (HMT) surfactant and zinc nitrate (Zn(NO3)2). The samples are crystalline with wurtzite phase. The morphological shape of the samples changes with the growth solution concentration. The optical absorption increases as the concentration increases. However, the band gap does not significantly change with the concentration. The DSSC utilizing the ZnO sample prepared at 0.1 M solution performs the best photovoltaic parameters with the JSC of 0.969 mA cm-2, FF of 0.48 and η of 0.222%, respectively since it shows the highest absorption and lowest photoluminescence in visible region.

This paper reports the effect of hexamethylenetetramine (HMT) concentration on the structural, morphological and optical properties of B-doped ZnO nanotubes arrays. B-doped ZnO nanotubes were employed as anode in dye-sensitized solar cells (DSSCs). The effect of these properties on the photovoltaic performance was also studied. B-doped ZnO nanotube arrays were prepared via hydrothermal technique on FTO substrate at constant concentration of zinc nitrate. The field emission scanning electron microscopy (FESEM) images indicate that the density and length of B-doped ZnO nanotubes increase with the concentration of HMT. However, the diameter decreases with the increase of HMT concentration. The JSC, VOC, FF and η of 1.48 mA cm−2, 0.38 V, 0.39 and 0.224% respectively have been obtained by the DSSC utilizing B-doped ZnO nanotube prepared at 0.06 M HMT.