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The dragline silk of spiders is of particular interest to science due to its unique properties that make it an exceptional biomaterial that has both high tensile strength and elasticity. To improve these natural fibers, researchers have begun to try infusing metals and carbon nanomaterials to improve mechanical properties of spider silk. The objective of this study was to incorporate carbon nanomaterials into the silk of an orb-weaving spider, Nephila pilipes, by feeding them solutions containing graphene and carbon nanotubes. Spiders were collected from the field and in the lab were fed solutions by pipette containing either graphene sheets or nanotubes. Major ampullate silk was collected and a tensile tester was used to determine mechanical properties for pre- and post-treatment samples. Raman spectroscopy was then used to test for the presence of nanomaterials in silk samples. There was no apparent incorporation of carbon nanomaterials in the silk fibers that could be detected with Raman spectroscopy and there were no significant improvements in mechanical properties. This study represents an example for the importance of attempting to replicate previously published research. Researchers should be encouraged to continue to do these types of investigations in order to build a strong consensus and solid foundation for how to go forward with these new methods for creating novel biomaterials.

Cu2O/TNA/Ti photoanode showed spectral response outperformed Cu2O/Ti and Cu2O/FTO photocathodes. Cu2O/TNA/Ti showed better spectral response than that of TNA/Ti, ascribed to UV-visible light absorption of Cu2O, not to charge separation enhancement.

Simple and low-cost homemade Rotating Analyzer Ellipsometer (RAE) configuration has been developed. Ellipsometer measures the changes of the reflected light polarization of the sample, yielding to the ratio of amplitude (ψ) and phase difference (Δ) between p- and s-polarization. Based on the ψ and Δ values, the dielectric constant of the sample can be extracted. However, the available manufacturer-made ellipsometer is quite expensive and is not a good choice for the student to learn the optical concept since the complexity of its structure could hide the simple optical concept during the measurement. In this work, we have built RAE that constituted of relatively simple components and low-cost as well as simple configuration. Here, we also show the principle of measurement and the ellipsometry data analysis using the optical model related to the system under study Drude-Lorentz model. The calibration of our SE has been done by measuring standard materials in the energy range of 1.5 to 3.3 eV and it was compared to the reference measurement using standard ellipsometer. The result is surprisingly accurate within the error of 5%. This research can be used for studying the several important optical concepts as well as for investigating nanostructured materials.

Oxygen vacancies (OVs) are common in cuprous oxide (Cu2O), and the effect of OVs on photocatalytic activity remains unclear. In this study, the photocatalytic activity of Cu2O photoanode with varying OV densities was investigated. The OV density in Cu2O was controlled by adjusting the Cu(CH3COO)2 concentration in a precursor solution used for the electrodeposition of Cu2O. The oxygen deficiency decreased from 5.2 to 0.4%, characterized through X-ray diffraction, when the Cu(CH3COO)2 concentration was reduced from 0.04 to 0.005 M due to the decrease in the mismatch between the concentrations of Cu(CH3COO)2 and OH–. The decrease in the OV density increased the excess photocharge density of Cu2O, as verified by photoluminescence and photovoltage measurements. Furthermore, the decrease in the OV density resulted in the enhancement of the spectral response and photocatalytic activity; this was attributed to the increase in the excess photocharge density. OVs in Cu2O mainly mediated the photocharge recombination and played a negative role in photocatalytic activity.

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The study of spectroscopic ellipsometry on gold thin film with different thicknesses (30, 50, and 70 nm) for biosensor application has been done. In this work, a rotating analyzer ellipsometer (RAE) has been used to characterize gold thin film and detect microalgae. The measurement was performed at different incidence angles (60°, 65°, 70°, and 75°) assuming the gold film as an isotropic material. The light absorptions of electron represented by the ellipsometer parameter (Δ) and the extinction coefficient (k) are due to the intraband transition of free electrons in the lower photon energy and interband transition of bounded electrons from 5d to 6sp in the higher photon energy. The light absorption increases with the decrease in the thickness of Au thin film. However, for the detection of microalgae, the light absorption of the electron increases with the increase in the thickness of Au thin film due to the dominant absorption by microalgae and PVA. We report that the use of Au thin film with the thickness of 70 nm provides the most sensitive detection of microalgae which is confirmed by the change in Δ (63.1°), at the photon energy of 2.11 eV and the incidence angle of 75°.

AbstrakPenelitian ini mencoba mendeskripsikan dan menganalisis bahasa mandarin, menyusun model pembelajaran yang sesuai dengan kebutuhan siswa sehingga minat belajar bahasa mandarin meningkat secara signifikan dan menjadikan pembelajaran bahasa mandarin sebagai program unggulan di SMA walisongo. Pendekatan yang dilakukan dalam penelitian ini mengadopsi pendekatan kualitatif. Teknik menggunakan wawancara, pengumpulan data observasi, dan dokumentasi. Hasil penelitian menunjukkan bahwa model pembelajaran bahasa Mandarin di SMA walisongo pecangaan jepara menggunakan model pembelajaran kolaborasi tiga model, alm mind, mapping atau role playing. Model ALM ( Audio Lingual Method) digunakan untuk menghafal, software model mind mapping digunakan untuk berlatih membaca dan menulis, dan metode role playing digunakan untuk berkomunikasi. Pencapaian hasil belajar bahasa mandarin SMA walisongo pecangaan memenuhi target yang diharapkan, melalui tiga model pembelajaran yang dijelaskan di atas menunjukkan bahwa siswa dapat menghafal kosakata dan ekspresi sebagai syarat peningkatan kelas. Selain itu siswa mampu membaca dan menulis serta berkomunikasi dengan lancar sesuai dengan prestasi belajarnya.Kata Kunci: Pembelajaran, Metode pembelajaran, Mandarin