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In the present study, the prepared covering material based on flax fibers containing caffeine, nano-copper, or corundum (Al 2 O 3 ) as a potential biocidal substance was prepared and tested on biological resistance. Two experimental designs were performed: a) the samples were placed in a desiccator at the air humidity of about 90 % and at a temperature of 25 °C for one month. The samples were then transferred to sterile agar and the coverage of the agars and the samples with molds were observed after a week of incubation. All samples were found to be infected. The samples containing copper were the least resistant. b) The samples were placed on sterile agar and the petri dishes were subjected to the fallout method, where both the samples and the agars were insulted by mold spores from the air. The Petri dishes with the samples were then placed in a thermostat in the dark at 25 °C for a week. After the end of the exposure, the samples and agars were observed. The samples were covered by molds with an increasing intensity in the following rank: caffeine sample = corundum sample < Cu sample = control sample = pure flax fibers.

Cancer is one of the main causes of death worldwide, being pancreatic cancer the second deadliest cancer in Western countries. Surgery, chemotherapy and radiotherapy form the basis of pancreatic cancer’s current treatment. However, these techniques have several disadvantages, such as surgery complications, chemotherapy systemic side effects and cancer recurrence. Drug delivery systems can reduce side effects, increasing the effectivity of the treatment by a controlled release at the targeted tumor cells. In this context, coaxial electrospun fibers can increase the control on the release profile of the drug. The aim of this study was to encapsulate and release different anticancer drugs (5-Fluorouracil and Methotrexate) from a polymeric fiber mat. Different flows and ratios were used to test their effect on fiber morphology, FTIR spectrum, drug encapsulation and release. Good integration of the anticancer drugs was observed and the use of a desiccator for 24 h showed to be a key step to remove solvent remanence. Moreover, the results of this study demonstrated that the polymeric solution could be used to encapsulate and release different drugs to treat cancers. This makes coaxial electrospinning a promising alternative to deliver complex chemotherapies that involve more than one drug, such as FOLFIRINOX, used in pancreatic cancer treatment.

Drying of cement paste, mortar, or concrete specimens is usually required as a pre-conditioning step prior to the determination of permeability-related properties according to standard testing methods. The reaction process, and consequently the structure, of an alkali-activated slag or slag/fly ash blend geopolymer binder differs from that of Portland cement, and therefore there is little understanding of the effects of conventional drying methods (as applied to Portland cements) on the structure of the geopolymer binders. Here, oven drying (60 °C), acetone treatment, and desiccator/vacuum drying are applied to sodium silicate-activated slag and slag/fly ash geopolymer pastes after 40 days of curing. Structural characterization via X-ray diffraction, infrared spectroscopy, thermogravimetry, and nitrogen sorption shows that the acetone treatment best preserves the microstructure of the samples, while oven drying modifies the structure of the binding gels, especially in alkali-activated slag paste where it notably changes the pore structure of the binder. This suggests that the pre-conditioned drying of alkali activation-based materials strongly affects their microstructural properties, providing potentially misleading permeability and durability parameters for these materials when pre-conditioned specimens are used during standardized testing.

In this study, wet chemical synthesis has been used to synthesize methyl ammonium lead iodide (CH 3 NH 3 PbI 3 ). Spin-coating method has been employed to deposit CH 3 NH 3 PbI 3 thin films of varying thicknesses on glass substrates. These samples were stored in vacuum desiccators and monitored over a 160-day period to investigate the degradation mechanism of perovskite thin films. To address the degradation issue, the degraded films were annealed at 70 °C for 30 min. During degradation, XRD data indicated a decrease in the intensity of CH 3 NH 3 PbI 3 peaks and an increase in PbI 2 peaks. After annealing, the intensity of CH 3 NH 3 PbI 3 peaks was partially restored, but PbI 2 was still present. Similarly, FESEM analysis revealed the presence of white, minute powder-like particles on the degraded samples and EDS data confirmed the presence of oxygen. However, the oxygen percentage decreased after annealing, and the white minute particles diffused. Subsequent analysis indicated that annealing partially restored the degraded films. Therefore, thermal annealing appears to be a possible solution to regenerate the degraded perovskite thin films.

Reducing electrode-related costs is an important step toward the large-scale commercialization of polymer solar cells. In this study, Cu is investigated as a low-cost top electrode in inverted polymer solar cells with the architecture ITO/ZnO/P3HT:PCBM/MoO3/Cu. The fabricated devices achieved a maximum power conversion efficiency (η) of 2.86%, with an open-circuit voltage (Voc) of 610 mV, a short-circuit current density (Jsc) of 6.90 mA cm−2, and a fill factor (FF) of 68%. Long-term stability tests were carried out over a period of 12 weeks under glovebox, desiccator, and ambient room conditions, during which efficiency decreases of 23%, 53%, and 78% were observed, respectively. Structural and spectroscopic analyses suggest that device degradation is closely associated with O2- and moisture-induced effects on the Cu electrode. The results demonstrate that Cu can be effectively employed as a top electrode in polymer solar cells under controlled environmental conditions, highlighting its potential as a cost-effective electrode material for polymer solar cell applications.

In the paper the chemical modification of activated carbon was presented. The activated carbon was modified by nitric acid. For the tested activated carbons, the following physical and chemical properties were determined: bulk density, pH of the water extract, and effective diameter of the grains. Elemental and technical analyses were performed. The pore distribution was determined using mercury porosimetry. Low-temperature nitrogen isotherms were used to analyze the microporous structure. The chemical properties of the surfaces of the tested adsorbents were interpreted by means of the Boehm method. The water vapor adsorption isotherms at 303 K were determined and the adsorption capacity towards methanol was tested using the desiccator method. Thermogravimetric tests were used and, at the same time, the released oxidizing gases from the tested samples were analyzed using a mass spectrometer. As a result of the modification, activated carbon enriched with acidic oxygen functional groups was obtained. The resulting modified activated carbon showed worse structural parameters (when compred to umodified activated carbon), however it was characterized by a higher adsorption capacity in relation to polar adsorbates such as water and methanol, especially in the low pressure range.

Porang tuber ( Amorphophallus muelleri B ) is a tuber from the Araceae family with a high glucomannan content (15-64% dry basis). Things that can be done to extend the shelf life of porang tuber flour are by doing the flouring process. This research aims to determine the isothermic curve model of Porang tuber ( Amorphophallus muelleri B ) flour, namely, the isothermic curve model used to estimate the equilibrium moisture content about the rh of storage. The research method used was to store samples of porang tuber flour in a desiccator with an rh interval of 17-80%. Storage was carried out until the sample’s water content reached equilibrium. Parameters of water content and determination of the best model based on the highest R 2 value at the end of storage of porang tuber samples while in the desiccator. The results of the research that has been done show that a material’s water content is affected by temperature and storage rh. To determine the best model, it is shown with the model that has the highest R 2 value. The Henderson model and Chung-Pfost model is the model that has the highest R 2 value. The value obtained at 30 °C is 0.9556, and at 40 °C is 0,9838. The model with the highest R 2 value indicates that the model is the best and most appropriate model that can be used to describe the best water absorption in porang tuber flour.

Recent multistate outbreaks of salmonellosis linked to fresh cucumbers underscore the importance of understanding Salmonella behavior on cucumbers under different storage conditions. No validated models that describe the impact of environmental factors on the growth of Salmonella on sliced cucumbers currently exist. This study developed mathematical models to predict the growth of Salmonella on sliced cucumbers at different temperature and relative humidity (RH) conditions. Sliced cucumbers were inoculated with a four-strain cocktail of Salmonella and placed in desiccators containing a saturated salt solution to create controlled RH environments (∼15, 50, and 100% RH) at 7, 14, and 21°C for up to 120 h. Predictive models were developed by using the Baranyi and Roberts equation as a primary model, and estimated kinetic parameters were fitted into a square root (or Ratkowsky) equation for secondary models. The maximum growth rates for Salmonella on sliced cucumbers depended on temperature but not RH. The square root model for Salmonella growth was √μ= 0.0297 × (T - 6.5185), with a high R2 value (0.98). The models in this study will be useful for future microbial risk assessments and predictions of Salmonella behavior in the cucumbers to manage the risk of Salmonella on sliced cucumbers.

The porous geopolymer has been tested for its content of water using impedance methods. The pores of the material were filled with distilled water using a desiccator and a vacuum pump. An analysis of differential scanning calorimetry (DSC) was carried out in the next step to check the content of water, porosity and approximate value of specific heat of the geopolymer. Additionally, mercury porosimeter has been used for checking the porosity. The geopolymer material characterized in this way was subjected to impedance tests aimed at developing a quick method for assessing the water content in the material. Impedance measurements have been realized on an electrochemical workstation applying a 50 mV non-destructive amplitude of the potential and a frequency range of 1 Hz to 100 kHz. Change in the module of impedance and the phase shift angle were measured while the material was dried out. Significant differences were observed. The obtained graphs were simulated using a schematic model consisting of constant phase elements (CPEs) and a resistor (R). These values showed mechanisms of charge conduction. A simple method for assessing the water content of a porous geopolymer has been proposed in this paper. The real and imaginary impedance values were shown in Nyquist graphs. These graphs have characteristic maxima that move according to a linear equation with decreasing water content. Changes in Nyqiust charts are clearly visible even with small changes in the water content of the material and can be very useful for assessing it.

Lignin as biofiller for this study was extracted from patchouli fiber waste using the soda pulping method, followed by acid precipitation of the spent liquor with sulfuric acid (H,SO4), as described in the methodology. Preparation of ternary bioblend composite Initially, a control blend of PLA and PHBV was prepared at a constant mixing ratio of 70:30, adopted from a previous study, using melt blending and compression molding [16]. (Taichung City, Taiwan) compression molding machine at 180 °C under a pressure of 10 MPa for 12 min in a metal mold with dimensions of 200x200x3 mm. The molded composites were cooled to room temperature in a cold press and conditioned for at least 48 h in a desiccator maintained at 50% relative humidity prior to characterization. 2.2. The tensile fractured surface morphology of pure PLA, pure PHBV, PLA/PHBV, and the PLA/PHBV/ Lignin ternary blend composite containing 9% biofiller was analyzed using a field emission scanning electron microscope (FE-SEM).