Bonding formation and gas absorption using Au/Pt/Ti layers for vacuum packaging

In this study, we developed a metal multilayer that can provide hermetic sealing after degassing the assemblies and absorbing the residual gases in the package. A package without a leak path was obtained by the direct bonding of the Au/Pt/Ti layers. After packaging, annealing at 450 °C caused thermal diffusion of the Ti underlayer atoms to the inner surface, which led to absorption of the residual gas molecules. These results indicated that a wafer coated with a Au/Pt/Ti layer can provide hermetic sealing and absorb residual gases, which can simplify vacuum packaging processes in the electronics industry.

Thermodynamic Optimization of Electrical and Thermal Energy Production of PV Panels and Potential for Valorization of the PV Low-Grade Thermal Energy into Cold

In the present study, the evaluation of potential improvement of the overall efficiency of a common PV panel, valorizing the heat extracted by a heat exchanger that is integrated on its back side, either into work using an endoreversible Carnot engine or into cold by using an endoreversible tri-thermal machine consisting of a heat-driven refrigeration machine operating between three temperature sources and sink (such as a liquid/gas absorption machine), was carried out. A simplified thermodynamic analysis of the PV/thermal collector shows that there are two optimal operating temperatures and of the panels, which maximize either the thermal exergy or the overall exergy of the PV panel, respectively. The cold produced by the endoreversible tri-thermal machine during the operating conditions of the PV/thermal collector at is higher with a coefficient of performance (COP) of 0.24 thanks to the higher heat recovery potential. In the case of using the cold produced by a tri-thermal machine to actively cool of an additional PV panel in order to increase its electrical performances, the operating conditions at the optimal temperature provide a larger and more stable gain: the gain is about 12.2% compared with the conventional PV panel when the operating temperature of the second cooled panel varies from 15 to 35 °C.

Experimental Study on Absorption Behavior and Efficiency of Brine in Hazardous Gas Absorption Treatment

There have been studies recently on bubble-column scrubbers with low cost and high efficiency for the absorption and treatment of hazardous gases in the event of a chemical spill. Bubble columns are vulnerable to freezing at temperatures below zero because the absorbents generally do not circulate. To address this issue, this study focused on the applicability, absorbed amount, and performance of brine as an absorbent. Under three different temperatures, i.e., −5 °C, −8 °C and −10 °C we examined brine (NaCl, CaCl2, and MgCl2) by varying the concentration required at each temperature. Following the experiments, CaCl2 brine was determined as the optimal brine for its absorption performance and affordability. Based on the experimental results, the absorption performance for ammonia, ethylene oxide, and methylamine, which are hazardous and water-soluble gases among accident preparedness substances (APS), was tested by using ASEPN PLUS. Our results suggested although the efficiency dropped by about 5% to 25% when brine was used as an absorbent, it can be used at the low temperatures because the gas solubility increased with decreasing temperature. Therefore, if brine, as an alternative, is used at temperatures about 15 °C, it can operate efficiently and stably without deterioration in the absorption performance. Given our experimental results and design data on the absorbed amount and absorbent replacement period for major hazardous gases are utilized to prevent bubble columns from freezing, it can be commercially used for small and medium-sized enterprises because it can help reduce installation and operation costs.

Non-Solvent Influence of Hydrophobic Polymeric Layer Deposition on PVDF Hollow Fiber Membrane for CO2 Gas Absorption

The implementation of hydrophobicity on membranes is becoming crucial in current membrane technological development, especially in membrane gas absorption (MGA). In order to prevent membrane wetting, a polypropylene (PP) dense layer coating was deposited on a commercial poly(vinylidene fluoride) (PVDF) hollow fiber membrane as a method of enhancing surface hydrophobicity. The weight concentration of PP pellets was varied from 10 mg mL−1 to 40 mg mL−1 and dissolved in xylene. A two-step dip coating was implemented where the PVDF membrane was immersed in a non-solvent followed by a polymer coating solution. The effects of the modified membrane with the non-solvent methyl ethyl ketone (MEK) and without the non–solvent was investigated over all weight concentrations of the coating solution. The SEM investigation found that the modified membrane surface transfiguration formed microspherulites that intensified as PP concentration increased with and without MEK. To understand the coating formation further, the solvent–non-solvent compatibility with the polymer was also discussed in this study. The membrane characterizations on the porosity, the contact angle, and the FTIR spectra were also conducted in determining the polymer coating properties. Hydrophobic membrane was achieved up to 119.85° contact angle and peak porosity of 87.62% using MEK as the non-solvent 40 mg mL−1 PP concentration. The objective of the current manuscript was to test the hydrophobicity and wetting degree of the coating layer. Hence, physical absorption via the membrane contactor using CO2 as the feed gas was carried out. The maximum CO2 flux of 3.33 × 10−4 mol m−2 s−1 was achieved by 25 mg modified membrane at a fixed absorbent flow rate of 100 mL min−1 while 40 mg modified membrane showed better overall flux stability.

PERAN RESPIRATOR DALAM PENCEGAHAN DAMPAK KESEHATAN AKIBAT POLUSI UDARA (STUDI KASUS DESA KLARI)

ABSTRAKPeran Respirator Dalam Pencegahan Dampak Kesehatan Akibat Polusi Udara Di Desa Klari, Kecamatan Klari, Kabupaten Karawang. Kegiatan ini di latar belakangi Desa Klari yang memerlukan perhatian terhadap peran respirator akibat dampak dari polusi udara. Selain itu, diharapkan dengan adanya Kegiatan Kuliah Kerja Nyata (KKN) ini dapat membantu masyarakat dalam meningkatkan kesadaran masyarakat akan pentingnya dampak polusi udara bagi Kesehatan di Desa Klari Kecamatan Klari. Hal ini dilakukan dengan cara menanyakan serta membagikan kuisioner ke masyarakat Desa Klari dengan adanya peran respirator bagi dampak Kesehatan akibat polusi udara. Dengan tingkat kesadaran masyarakat yang masih minim terhadap pentingnya peran respirator terhadap Kesehatan akibat polusi udara. Hal ini didasari dengan kondisi polusi udara di Desa Klari yang terbilang tidak terlalu baik akibat adanya polusi dari banyaknya kendaraan bermotor, asap pabrik, dan kegiatan pembakaran yang sembarangan. Dengan adanya kegiatan KKN di Desa Klari diharapkan tidak hanya dalam peningkatan peran respirator bagi masyarakat Klari tapi dihimbau bagaimana cara menanggulangi polusi udara dengan cara menanam pohon yang mengandung daya serap gas karbondioksida (CO2) dan pembuatan tong sampah guna mengurangi tingkat volume sampah di lingkungan Desa Klari. Kata Kunci: respirator; polusi; karbondioksida (CO2); desa klari; volume. ABSTRACTThe Role of Respirators in Preventing Health Impacts Due to Air Pollution in Klari Village, Klari District, Karawang Regency. This activity is in the background of Klari Village which requires attention to the role of respirators due to the impact of air pollution. In addition, it is hoped that this Real Work Lecture (KKN) activity can help the community in increasing public awareness of the importance of the impact of air pollution on health in Klari Village, Klari District.This is done by asking and distributing questionnaires to the Klari Village community with the role of respirators for health impacts due to air pollution. With the level of public awareness that is still minimal on the importance of the role of respirators on health due to air pollution. This is based on the condition of air pollution in Klari Village which is not very good due to pollution from many motorized vehicles, factory smoke, and indiscriminate burning activities.With the KKN activities in Klari Village, it is expected not only to increase the role of respirators for the Klari community but are also encouraged to overcome air pollution by planting trees that contain carbon dioxide gas absorption (CO2) and making trash cans to reduce the level of waste volume in the Klari Village environment. . Keywords: respirators; pollution; carbon dioxide (CO2); klari village; volume

Preparation and properties of an intelligent adjustable functional paper for organic cultural relics

Precious organic cultural relics are easily affected by temperature, humidity, and harmful gases in the environment, resulting in embrittlement, fading, mildew, moth damage and other aging forms. An energy-saving and environmentally friendly material is needed to stabilize humidity and adsorb harmful gases in the environment. In this paper, with an intelligent adjustment function, functional paper containing sepiolite and tourmaline natural minerals was successfully prepared. The component of 80 % of wingceltis and 20 % of straw in dry pulp as main raw material was conducive to the desorption of water molecules. As favorable structure inside functional paper, the adsorption point and the adsorption contact area increased by the rough surface of fiber bundles, the addition of sepiolite and the ordered molecular chains of copolymers destroyed. So, the relative humidity could be adjusted to 55 % ± 3 within 2 hours and was stable with functional paper. At the same time, 1.11 ppm sulfur dioxide and 2.98 ppm ammonia could be effectively adsorbed in 10 and 12 h, respectively, by 1 g of paper in a 5 L container. The pH of the paper was adjusted to neutral with tourmaline, even if the pH was changed by acidic or alkaline gas absorption. Therefore, for long-term organic cultural relic preservation, preparing a constant-humidity and clean environment is of great significance. This is possible through this paper.