We present alternative methods to oxidize a graphene layer through ultraviolet (UV)/ozone (O3)-treatment, resulting in chemically homogeneous graphene oxide (GO), and then to reduce GO through UV-irradiation. Both UV/O3-treatment and UV-irradiation were performed at room temperature in atmospheric pressure for only several minutes and did not involve any wet chemical treatments. The quantity of doped oxygen, determined using X-ray photoelectron spectroscopy, increased after oxidation and decreased after reduction. The quantity of doped oxygen reached its maximum, which was around 20% (approximately one oxygen atom in every five or six carbon atoms) after performing UV/O3-treatment for 6 to 10 min. Conducting UV/O3-treatment for around 6 or 10 min resulted in a chemically homogeneous GO surface with only oxygen epoxide groups on the graphene surface. Performing UV/O3-treatment beyond 15 min as well as multiple turns of UV/O3-treatment could lead to the formation of defects and carbonyl groups on graphene lattice. The oxygen quantity gradually decreased after conducting 6 min UV-irradiation several times, indicating that the resulting GO was successfully reduced. How the doped oxygen atoms distributed on graphene surface was directly investigated using scanning tunneling microscopy. Moreover, changes in electrical properties of three identical single-layer graphene field-effect transistors (G-FETs) after being oxidized through UV/O3-treatment were investigated. The electron mobility of G-FETs decreased after oxidation; however, it recovered after irradiating the oxidized G-FETs with UV-lights, indicating that GO was successfully reduced nonthermally through UV-irradiation. The reversibility in electron mobility was confirmed even after conducting redox processes twice. Furthermore, the reversibility of oxidation was also verified from the graphene lattice disorder point of view using Raman spectroscopy. We concluded that UV/O3-treatment produced chemically homogeneous GO that is nonthermally reversible through UV-irradiation, and changes in the electron mobility were nonthermally reversible also.

An alternative way to construct a stable p-n junction on graphene-based field effect transistor (G-FET) through physical adsorption of ferritin (spherical protein shell) is presented. The produced p-n junction on G-FET could also operate through water-gate. Native ferritins are known to be negatively charged in wet condition; however, we found that native negatively charged ferritins became positively charged after performing electron beam (EB)-irradiation. We utilized this property to construct p-n junction on G-FET. We found also that EB-irradiation could remove the effect of charged impurity adsorbed on graphene layer, thus the Dirac point was adjusted to gate voltage Vg = 0.

Changes in electrical properties of a bilayer graphene-based field-effect transistor (G-FET) after being oxidized through ultraviolet (UV)/ozone (O3) treatment are presented. A decrease in conductivity and carrier mobility was observed after oxidation. However, electrical properties recovered after annealing oxidized G-FET with H2/Ar, indicating that oxidation with UV/O3 treatment was thermally reversible. Raman spectroscopy was conducted to verify that no defects were introduced after oxidation. The existence of chemical bonds between oxygen and graphene was confirmed from the X-ray photoelectron spectroscopy. Moreover, we found that graphene's sheet resistance increased after oxidation. Nevertheless, contact resistivity at graphene-Au/TiN electrode interface remained unchanged.

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Saat ini masyarakat banyak beralih berbelanja di pasar modern daripada di pasar tradisional, karena pasar modern cenderung lebih bersih, serta dikelola lebih profesional.  Selain pasar modern, pasar online menjadi salah satu ancaman keberadaan pasar tradisional.  Agar pasar tradisional tidak tenggelam dan tertinggal dengan pasar modern dan pasar online, maka pedagang pasar di pasar tradisional harus mengikuti perkembangan jaman terutama dengan  berkembangnya teknologi internet sekarang ini dengan  memasuki pasar di dunia maya yang disebut sebagai electronic commerce (e-commerce). Saat ini terdapat peluang yang besar untuk melakukan pemasaran dengan memanfaatkan teknologi internet yaitu melalui media sosial. Melalui media social, bisnis mendapatkan akses berkaitan dengan sumber daya yang lebih besar dan lebih luas bagi pemilik bisnis. Penelitian ini merupakan penelitian kausal. Obyek penelitian ini adalah seluruh pedagang yang ada di Pasar Tradisional, dengan pengambilan sampel menggunakan teknik random cluster sampling (random area sampling). Data dikumpulkan  menggunakan kuesioner. Pengujian hipotesis menggunakan analisis deskriptif, pengujian asumsi klasik, analisis regresi berganda, pengujian hipotesis dan analisis koefisien determinasi.  Berdasarkan analisis data dapat disimpulkan bahwa kemampuan e-commerce berpengaruh tidak signifikan terhadap kinerja pemasaran, promosi di media sosial berpengaruh signifikan terhadap kinerja pemasaran serta  kemampuan e-commerce dan promosi di media sosial secara simultan berpengaruh signifikan terhadap kinerja pemasaran

In order to evaluate the interaction between biomaterials and graphene from the perspective of its ambipolar characteristic, we have investigated the alteration in ambipolarity of graphenebased field effect transistors (G-FET) after the adsorption of Escherichia coli (E. coli) bacteria onto its graphene layer. We confirmed a positive shift in the ambipolar curve of the G-FETs after the adsorption of E. coli, presumably due to the negative charge of the adsorbed E. coli. However, we did not observe any decrease in the electron mobility or conductivity of the G-FETs, which implied that E. coli did not chemically react with the carbon atoms of graphene, nor introduce any damage on the graphene lattice, but were only physically adsorbed onto the graphene surface. These findings may extend the prominence of graphene as a stable yet sensitive material to be fully utilized in future biosensing applications. These results were then compared to those of ferritin adsorption, which is a protein shell and biomaterial like E. coli, and radical oxygen doping onto the graphene surface.

Fusarium wilt disease/moler is a concern in onion cultivation. Many farmers apply chemical pesticides such as azoxystrobin and difenoconazole to control the diseases. Both of these chemical pesticides are currently exhibiting a decline in effectiveness, prompting farmers to increase the dosage and frequency of application. Recommendations for biological control, including Trichoderma spp.. This study aimed to determine the influence of application time of of Trichoderma spp. in various media types on the incidence of moler disease and shallot growth and yield. This study was conducted in Tabalong district, South Kalimantan, from February to June 2019 using a completely randomized design (CRD) factorial comprising two nested designs. The first factor was the type of media in which Trichoderma spp.. was applied, namely solid and liquid. The second factor was the application time of Trichoderma spp.. Level 1 was the application of Fusarium sp. seven days before planting and Trichoderma spp.. seven days after planting. Level 2 included the application of Trichoderma spp.. seven days before planting and Fusarium sp. simultaneously during planting. Level 3 involved the administration of Trichoderma spp.. concurrently with planting and Fusarium sp. seven days later. This investigation used one positive control (without treatment) and one negative control (shallots inoculated with Fusarium). Each experimental unit was consisted of ten plants and replicated three times. The parameters observed were the incubation period of Fusarium sp., disease incidence, number of leaves, plant height, number of cloves, and average clove weight. The study found that the application time of Trichoderma on various types of media affected the incidence of Fusarium disease, the number of leaves, and the number of shallot cloves.When compared to liquid media, the application of solid media resulted in a reduced incidence of Fusarium disease and a greater frequency of flares. The application time on solid media gave a low response to moles. As for liquid media, the lowest incidence of moler disease occurred at the seven days before planting.

The purpose of this study is to describe and analyze the partial and simultaneous influence of member deposits and financing on profit (SHU) on KSPPS BMT Sinergi Cendekia Indonesia. The research approach used is a quantitative approach with descriptive-analytical methods, the data source used is a five-year safe secondary data, the data collection techniques used are library studies and documentation. The data analysis technique used is multiple linear regression analysis. The results showed that partially member deposits did not affect SHU, financing did not affect SHU and simultaneous deposits and financing did not affect SHU. The implication is that the SHU forming component in BMT does not have to be formed from financing activities alone but can be formed from real sector activities and partnerships between BMT as developed by KSPPS BMT Sinergi Cendekia Indonesia.