# Science

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With open facilities, the Brazilian Synchrotron Light Laboratory (LNLS) annually welcomes about 1200 Brazilian and foreign researchers, committed to more than 400 studies that result in approximately 200 articles published in scientific journals. Check out below some of the many investigations that have benefited from LNLS facilities.

# Electronic Structure of Magnetic $\rm Fe_3 Ga_4$ Nanowires

It is reported the magnetic characterization of the Fe3Ga4 intermetallic compound synthesized by the MFNN technique.

Nanowires belong to a new class of quasi-unidimensional materials that have been attracting great interest due to their numerous potential applications, such as functional materials in biomedical sciences, electronics, optics, magnetic devices and energy storage. Among the several ways to produce nanowires, one can mention template-assisted fabrication, vapor-liquid-solid mechanism, molecular beam epitaxy and electrochemical nanolithography. In particular, nanoporous alumina membranes have been widely used as templates for magnetic nanowire arrays produced by electrochemical deposition due the simplicity, versatility, efficiency and low cost implementation of this technique. However, the nanowires obtained by this way generally present poor crystallinity and are restricted to metallic alloys.

# Neutron and Synchrotron Diffraction Studies of BCZY27 Proton Conductor

A detailed analysis highlights several structural complexities of the (BZCY72) perovskite.

High-temperature electrochemical devices exhibiting the preferential transfer of protons have the potential to produce a shift to a sustainable energy economy in which hydrogen replaces hydrocarbon sources as the principal fuel for stationary power and transportation. Protonic ceramic fuel cells (PCFCs), with a proton-conducting ceramic electrolyte membrane, cleanly convert the chemical energy of hydrogen to electrical energy in an intermediate temperature range (773−1023 K). This interval neatly alleviates the technological problems and costs associated with the higher operating temperatures of contemporary solid oxide fuel cells based on an oxide-ion conducting electrolyte and those of the polymeric devices which require expensive electrocatalysts due to the low operation temperature, below 373 K.

# Viral Inhibition Mechanis Mediated By Surface-modified Silica Nanoparticles

The results demonstrate for the ﬁrst time the antiviral activity of mSiO2 particles.

Viruses are among the most harmful pathogens and are responsible for the death of millions of people every year. Even after the development of the highly active anti-retroviral therapy which improved the quality of life and increased the life expectancy of patients with AIDS, human immunodeﬁciency virus (HIV) alone was responsible for the death of 1.2 million people in 2014. The development of new strategies to ﬁght viruses is necessary, as antiviral therapies and other eﬃcacious vaccines are not available for many viral diseases. Tailored nanostructures have emerged as a possible alternative, since they have shown activity against dierent viruses, including hepatitis B, virus human immunodeﬁciency virus, herpes simplex virus, respiratory syncytial virus, adenovirus, monkey pox virus, inﬂuenza, and H1N1 inﬂuenza A viruses. However, not much is known about the nanostructures mechanisms of antiviral action.

# Enhancing Carrier Mobility in Organic Transistors

The small interface roughness and polarization phenomena lead to a larger charge-carrier mobility and better operational stability.

# New Method To Produce Highly Efficient, Stabilized Au-TiO2 Catalysts

New catalyst shows a potential for industrial applications requiring durability and high thermal stability.

# Enhanced Photocurrent With Hexagonal Cu2Te In Polymers Thin Films

Hexagonal-shaped Cu2Te nanodisks self-organize into a network of ribbons fully embedded in rr-P3HT thin films.

Hybrid nanocrystal-polymer materials are of great importance for the solution-based fabrication of thin films with tailored optical and electronic properties for sensing, light emission, and photovoltaic applications. The excellent control over size, shape, and composition of inorganic nanocrystals (NCs) allows tuning of their physical properties and makes them interesting materials for devices, ranging from optoelectronics to medicine. On the other hand, polymers can also be synthesized with customized properties to fulfil a wide range of functionalities. Organic electronics has indeed seen a significant progress in the last years thanks to the synthesis of highly performing polymer semiconductors and conductors.

# Successful Oxidation Induced Doping Of Nanoparticles Revealed By In Situ XAS

The ﬁrst real-time in situ XANES/EXAFS study of the formation kinetics of Mo-doped and undoped fe oxide NPs.

Doping has led to a revolutionary breakthrough in the design of semicondutor devices. Yet, it is still challenging to introduce dopants in nanoparticles (NPs) in order to access properties unavailable in the undoped materials. Diﬀerent types of interactions between host and dopant are responsible for the properties of doped NPs. The new properties in doped NPs may originate from spin exchange interactions between the dopant and host, presence of long-lived highly isolated electronic states, or simply from high concentration of structural defects.

# New discoveries about human hair

Although always on our minds – but not so much on our heads –, there is still plenty to be known about the structure and composition of human hair.

Scientists find beta-keratin in the hair, typical of reptiles and birds Although always on our minds - but not so much on our heads –, there is still plenty to be known about the structure and composition of human hair. Far from a simple scientific curiosity, the proper knowledge about it allow us, for example, to research and develop new and more efficient cosmetic products for the hair treatment and care.

# Nanotechnology for measuring vitamin C

Scientists develop quick method for quantifying ascorbic acid in solutions.

Scientists develop quick method for quantifying ascorbic acid in solutions Brazil is world leader in the production and exportation of orange juice. According to the Ministry of Agriculture, the country is responsible for 30% of the world’s annual harvest but 60% of the world’s annual juice production, 90% of which is exported.

# On the way to a new generation of integrated circuits

Researches look for new materials for extreme ultra-violet lithography.

Researches look for new materials for extreme ultra-violet lithography

Cellphones, computers and other omnipresent portable electronic devices owe their existence to the continuous miniaturization of electronic circuits, which begun with the invention of the transistor, in 1947.