On-chip light scattering imaging of the guanine platelet

A guanine platelet is a very thin optical component that plays a role in light reflection control in the narrow space within the body of a fish. However, the details of this light control mechanism have not been revealed to date. In this work, guanine micro-platelets floating in water are visualized via light projection near an image sensor. These guanine platelets demonstrate light scattering toward specific directions. By setting a thin water layer on top of the image sensor’s cover glass, each platelet in the water layer forms column- or bar-code-shaped images on the screen. The existence of nanohole gratings in these platelets was confirmed by high-resolution optical microscopy. Numerical electromagnetic simulations indicated that the nanohole gratings contributed to the formation of unique light projection spots.

Smart Glass Coatings for Innovative BIPV Solutions

The glossy appearance of the cover glass of a photovoltaic module is mainly responsible for giving the module a mirroring effect, which is often disturbing in the case of building integrated photovoltaic (BIPV) façade applications. In this work, an innovative approach is presented to reduce the glare of BIPV modules by applying surface coatings to the front glass of the module. Three different glass coating technologies, applied on the outer surface of the photovoltaic module, were investigated: inkjet printing, screen printing, and sol-gel spray coating. The coatings, applied by these technologies in three different colours (grey, anthracite, and terracotta), were characterized with respect to their adhesion, light transmission, and reflection. Their chemical and physical stability after stress impact (condensed water resistance and chemical resistance against acids and salt-fog) was also investigated. The durability of these coatings was further evaluated after performing environmental simulations with artificial sunlight (xenon weathering) on coated glass. Additionally, accelerated aging tests (damp-heat testing, temperature cycling) were performed on the test modules to assess their performance stability. For those coatings, where no stress-induced changes in colour or the optical appearance of the module surface were detected, the potential for the architectural integration of the modules into building facades is high. A minimum glare of less than 0.1% of the specular reflection could be achieved. On the basis of the results of the optical characterization and the durability tests, grey screen-printed BIPV solar modules were installed in a demonstrator test façade. The high electrical performance, resulting in only a 10–11% performance decrease compared to the noncoated reference modules, perfectly showed the suitability of screen-printing in future applications for coloured and glare-reduced BIPV installations.

PERFORMANCE COMPARISON AND OUTDOOR MONITORING OF SMOOTH AND TEXTURED COVER GLASS FOR SOLAR MODULES OF UP 6 YEARS EXPOSED

Solar modules are being built with nearly the same configuration for decades now. The front is covered with a tempered glass pane. The performance of a PV module can be increased by the texturation of the front side. One of the major requirements for front cover glasses is their high optical transmission. One option to boost transmission is texturing the front surface in a similar manner to crystalline solar cell. Another advantage of a textured glass is the fact that the reflected light beam at normal incidence has a second chance of being transmitted to the solar cell. Furthemore, the texturation of front cover glass might collect more dust and soiling than a flat glass surface. Due to this concern, the soiling effect of module covered with textured cover Alberino P glass after long-term exposed will investigated in this work. The modules presented in this work have the same characteristics in STC (i.e short circuit current, open circuit voltage and maximum power point). Electroluminescence, I-V and P-V characteristic are the method used to detect faults on the PV module. The results show a loss of PV performance with textured cover glass is l,72% higher than the reference module in other hand the increase of serie resistance is also observed in both modules

Hydrogen Peroxide Gas Plasma Sterilizer Combined with Dielectric Barrier Discharge and Corona Discharge Inactivates Prions

Prions are highly resistant to physical or chemical damage, although previous studies have shown that STERRAD®, a hydrogen gas plasma sterilizer using radiofrequency (RF) discharge, has an inactivation effect. Here, the effect of hydrogen peroxide gas combined with dielectric barrier discharge (DBD) plasma and corona discharge plasma using a RENO-S130 sterilizer on scrapie prions was examined. Scrapie prion-infected mouse brain homogenate was air-dried on a cover glass, sealed in a Tyvek pouch, and subjected to RENO-S130 treatment using either non-lumen mode (28 min) or Eco mode (45 min) with hydrogen peroxide gas derived from 50% hydrogen peroxide. Control (untreated) samples were prepared on a cover glass using the same procedure but without exposure to RENO-S130. PrPres (proteinase K (PK)-resistant prion protein), an index of the conformational variant of prion protein (PrPSc), was decreased by treatment with RENO-S130 under both modes of operation. Specifically, PrPres was identified after the 1st and 2nd cycles of protein misfolding cyclic amplification (PMCA) in control samples but was below the detection limit in RENO-S130-treated samples. A bioassay showed that treatment of prions with RENO-S130 (non-lumen or Eco mode) significantly prolonged mouse survival time. Taken together, these findings show hydrogen peroxide gas combined with DBD/corona discharge plasma can inactivate prions by reducing prion propagation and prion infectivity. This treatment is potentially applicable to the sterilization of prion-contaminated heat-sensitive medical devices.

Characteristics of Functional Film Synthesized on the Cover Glass of Photovoltaic Modules

In this study, the characteristics of functional films were investigated according to the number of coatings and their heat treatment times. The functional coating films were deposited on glass substrates made of the same material as the cover glass of photovoltaic (PV) modules. Each film was coated once by brushing with a special silica-based solution, and each heat treatment was done using a hot-air fan for 2 min at 300 °C. The substrates were coated once, twice, and thrice, respectively, and were annealed once, twice, and thrice by drying and cooling alternately. The specimens were then analyzed for their anti-pollution properties, contact angles, light transmittance, and mechanical properties. The anti-pollution function was confirmed through a self-cleaning test, while the contact angle and light transmittance were examined using special equipment. Mechanical properties, including hardness and adhesion, were confirmed using the standard hardness testing method (ASTM D3363) such as those using an H-9H, F, HB, or B-6B pencil (Mitsubishi, Japan) and a standard adhesion testing method (ASTM D3359). It was confirmed that the film coated once yielded a very low contact angle of 8.9° and very good anti-pollution properties. Its adhesion and strength also showed high values of 5B and 9H, respectively.

Multi-Walled Carbon Nanotube-Assisted Encapsulation Approach for Stable Perovskite Solar Cells

Perovskite solar cells (PSCs) are regarded as the next-generation thin-film energy harvester, owing to their high performance. However, there is a lack of studies on their encapsulation technology, which is critical for resolving their shortcomings, such as their degradation by oxygen and moisture. It is determined that the moisture intrusion and the heat trapped within the encapsulating cover glass of PSCs influenced the operating stability of the devices. Therefore, we improved the moisture and oxygen barrier ability and heat releasing capability in the passivation of PSCs by adding multi-walled carbon nanotubes to the epoxy resin used for encapsulation. The 0.5 wt% of carbon nanotube-added resin-based encapsulated PSCs exhibited a more stable operation with a ca. 30% efficiency decrease compared to the ca. 63% decrease in the reference devices over one week under continuous operation. Specifically, the short-circuit current density and the fill factor, which are affected by moisture and oxygen-driven degradation, as well as the open-circuit voltage, which is affected by thermal damage, were higher for the multi-walled carbon nanotube-added encapsulated devices than the control devices, after the stability test.

On-chip light diffraction imaging of nano structures in the guanine platelet

Light projection over short distances can minimize the size of photonic devices, e.g., head-mounted displays and lens-free microscopes. Small lenses or light condensers without typical lenses are essential for light control in micron-scale spaces. In this work, micro-platelets floating in water are used for light projection near the image sensor. These platelets, which are made from guanine, have nanohole gratings and demonstrate light diffraction toward specific directions. By setting a thin water layer on the image sensor's cover glass, each platelet in water forms column- or bar-code-shaped images on the screen. The projected image shapes and colors are inferred to contain information about nano-structures present in the guanine platelet. The proposed down-sized imaging technique can realize extremely compact and portable imagers for nanoscale object detection.