Synthesis of silver nanoparticles, as potential mercury metal detection, using Lamtoro Pods extracts has been successfully carried out by the green reduction method. The peak spectrum of plasmon resonance (SPR) at 415 nm confirmed the formation of silver nanoparticles. The Fourier transform infrared (FTIR) test obtained a characteristic functional group vibration spectrum in Lamtoro Pods. A shift of wavenumber was distinguished by comparing the FTIR spectrum between Lamtoro pods extract and silver nanoparticles. This indicated the involvement of phenol and flavonoid compounds found in the Lamtoro act as a reducing agent of Ag + to Ag 0 (silver nanoparticles). The X-ray diffractometer (XRD) pattern showed that the material synthesized as silver nanoparticles. The transmission electron microscopy (TEM) characterization showed that the nanoparticles have an average size 15.70 nm. The color intensity of silver nanoparticles decreased to be colorless after being contacted with mercury ion, indicating its potential for mercury metal ions detection.

This article reports the results synthesis of composite Fe3O4/SiO2 and nanoparticles from natural resources (sugarcane bagasse). The synthesis of Fe3O4 and SiO2 nanoparticles used co-precipitation and sol-gel methods with SiO2 from sugarcane bagasse as a template. The XRD data analysis presented that Fe3O4 were successfully produced using co-precipitation methods. The XRD data analysis also presented that the crystalline phases showed Fe3O4. FTIR spectra presented some absorption peaks of new functional groups indicating the existence of Si-O-Si (silanol), Fe-O, and Fe-O-Si as new functional groups.

Bricks are regarded as important material in building constructions. Basically, brick is processed by mixing clay and water then burnt under high temperature for a certain duration. Previous study in Indonesia shows that mixing local clay with additional materials could improve its characteristic, especially in terms of water absorption potentiality. Lampung has home industries which run brick making business traditionally. Moreover, this year Indonesian government has been organizing regional elections which attract campaigners to produce more vinyl banners as advertising media. As the event has already passed, vinyl banners eventually become environmental issue since they are not yet well managed. The aim of this study is to investigate the possibility and effect of red bricks mixtures along with vinyl banner waste. Firedclay bricks dimensions including length, width, and height are 19 cm, 9.5 cm, and 5 cm respectively. Measurement has done by employing water absorption tests. Waste-added bricks absorb more water than the conventional one, about 11% higher. However, rice-husk-ash-added bricks perform similar to the normal bricks, it has slow rate of water absorption. Absorption rate of waste-added bricks also fast and exceed the conventional and RHA-added bricks. Modified red bricks surfaces are uneven, they show cracks and rough edges.

The regional election in Lampung province has finished. The events left the amount of ex-campaign props such as banner to become waste. The final landfills and the waste reuse system are still an unsolved issue in Lampung province. A study of materials composition is required to find potential reuse of the waste. One of the traditional products in Lampung province is conventional bricks. Previous studies show that mixing local clay with additional materials such as Rice Husk Ash (RHA) could improve its characteristics, especially water absorption potentiality. This study reported the prototype of bricks with banners waste mix produced employing a conventional method. The method obtains the best admixture composition is 0.002 kilograms banner waste/volume 0.125 liters or 0.02% total weight of clay-dough. The morphology of the prototype shows a similar texture with a non-waste mixture of traditional brick. It is burnt-clay red-bricks, which is used as a control in this study. The prototype bricks show smooth texture and nearly flat on all sides. The addition waste composition ratio of more than 0.002 kilograms indicated cracking texture that affects the market tend to buy bricks, which has good appearance and texture. This study also reported that the mixture's effect is decreasing compressive strength, almost 20% from the control sample.

Nowadays, invisibility efforts by scientists and engineers have focused on building a large broadband, multidirectional cloaking device. The device is usually a cloak that works in macroscopic dimensions and for the entire visible spectrum. Addition with the full-field of light, no new materials, simple infrastructure, and scale easily may be considered an 'ideal' cloaking device. This paper report of implementing ray optics cloaking formalism presented previously by Choi and Howell [1] using lenses design for cloaking arbitrarily large, and moving objects such as large vehicle. We apply their formalism using simulation and experiment scheme to general optical systems up to four convex lenses. The results support the information to create optical cloaking prototype for optimizing large vehicle driver's visibility as alternative solution for decreasing traffic accident in Bandar Lampung.