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UV fluorescence imaging (UVF) has the potential to grow into a powerful, informative, and economically attractive inspection method for photovoltaic (PV) power stations. UVF demonstrates the ability to indicate differences in polymer types and degradation states in backsheets and encapsulation materials of PV modules. The data acquisition rate of UVF measurements is 10 to 15 times higher than that achieved by state‐of‐the‐art near‐infrared spectroscopy, enabling the mapping of the bill of materials (BoMs) and degradation state for every module in large PV arrays. Combinations of UVF with vibrational spectroscopies allow the polymer BoMs to be recognized and correlated with aging phenomena such as metal corrosion or potential induced degradation. UVF imaging can also be used for conventional visualization of nonmaterial‐related anomalies, such as hot cells or cell cracks. The low purchase cost of the equipment makes UVF an affordable and high‐throughput diagnostic method yielding comprehensive information that would otherwise only be accessible by combining several slower and more laborious methods. Automated UVF image analysis and refinements of correlations between different BoMs and UVF pattern geometry can further unlock the potential of UVF as a straightforward tool accessible to all stakeholders and promote proactive strategies for the optimization of the reliability and performance of PV power stations. [ABSTRACT FROM AUTHOR]

The degradation status of polymer encapsulants in photovoltaic (PV) modules with backsheets of various compositions is evaluated by near‐infrared absorption (NIRA) spectroscopy. The method is used to identify backsheet types and to assess the content of carbonyl species in the ethylene vinyl acetate copolymer encapsulant expressed as a carbonyl index (CI). The CI distributions are collected for PV modules of different ages and in different climatic conditions from twelve PV installations in Europe (EU) and South Africa (ZA) and the peak of the index distribution is found to be related exponentially to the total dose of solar irradiation. The CI growth rate with the irradiation dose in EU is around two times larger than in ZA, most probably due to more massive moisture ingress into PV modules installed in a more humid EU climate. For similar total solar exposures, the CI is found to depend on the backsheet structure. Repeated measurements on the same plant after an additional 2 years of module operation confirm the capacity of NIRA spectroscopy to track the temporal progression of encapsulant degradation using CI as a quantifier depending on the encapsulant‐backsheet bill of materials, plant age, and climatic zone. [ABSTRACT FROM AUTHOR]

Affordability, Long-term warranty, scalability, as well as continuous decline in the LCOE (levelized cost of electricity) of PV (Photovoltaic) in many nations, are largely responsible for the current enormous up thrust in global installation of solar PV modules, at residential roof-top as well as utility-scale systems. Also, as the world’s energy portfolio evolves toward cleaner energy sources, PV deployment is anticipated to maintain this increasing trend. Despite this, these PV modules are subjected to a broad range of climatic conditions in outdoor application, regardless of the PV module material/type and technology used. These modules are frequently subjected to high chemical, photochemical, and thermomechanical stress because of the reason that these PV modules are exposed to extreme environmental conditions. In addition to manufacturing flaws, these circumstances have a greater impact on the aging rate, flaws, and degradation of PV modules. As a result, different investigations on PV dependability and degradation mechanisms have been conducted recently. These studies not only shed light on how the performance of PV modules deteriorates with time, but most importantly, they provide useful input for future advancements in PV technology and performance forecasting for more accurate financial modeling. Due to this, it is crucial to quickly and accurately identify and classify the degradation modes and mechanisms caused by manufacturing flaws and environmental factors in order to reduce the likelihood of failure and the risks that go along with it. Visual examination, EPM (Electrical-Parameter-Measurements), imaging techniques, and latest data-driven techniques have all been suggested and used in the literature to assess or describe the deterioration signatures and mechanisms/pathways of PV modules. This report offers a critical analysis of recent research that examined the performance reliability and deterioration of solar PV systems. The objective is to identify important topics, advance the state of the art, and offer well-considered suggestions for upcoming research, especially in the field of data-driven analytics. Data-driven analytical methods, such as DL (Deep Learning) ML (Machine Learning) models, have astounding computational abilities to process large amounts of data, with diverse features, and with minimal computation time. This contrasts with visual inspection and statistical approaches, which are more time-intensive and require significant human experience. They can therefore be used to evaluate the performance of a module in manufacturing, field deployments, and lab settings. DL and ML can observe erratic patterns and draw useful conclusions in the classification, diagnosis, and prediction of PV performance degradation signatures thanks to the enormous size of PV module installations, particularly in systems for utility scales, and the large datasets produced in terms of features from imaging and EPM data. In terms of methodology, datasets, characterization techniques, accelerated testing procedures, feature extraction mechanisms, classification procedures, analysis and comparison and critical analysis of solar PV deterioration models. Lastly, we briefly describe any potential research gaps and briefly list some suggestions for additional research.

Lulo (Solanum quitoense Lam.) is an exotic fruit with high potential in international markets due to its intense aromatic characteristics and its content of nutritional and bioactive compounds. However, it is highly perishable, which backslashes its potential for international exportation. Despite the drying processes affect the nutritional and sensory characteristics, fruit powders obtained by spray drying are promising products for the food, cosmetic, and pharmaceutical industries. This work was conducted aiming to optimize the spray-drying process of lulo pulp. A Box-Behnken design with response surface methodology was used, in which the factors evaluated were inlet air temperature (160 - 220 °C), maltodextrin concentration (15-35%), and whey protein concentration (WPC) (1-5% w/w). The feed rate and air velocity were kept constant at 4 mL/min and 9 m/s, respectively. The optimization resulted in an inlet air temperature of 205.6 °C, 35% maltodextrin, and 1.96% WPC. Under these conditions, the mathematical model estimated a powder yield of 62.8%, a moisture content of 2.3 %, a bulk density of 0.49 g/mL, a solubility of 91.9 %, and an ascorbic acid content of 120.8 mg/100 g powder. The optimal process conditions and the mixture of encapsulants (MD and WPC) allow for obtaining lulo powder with adequate yield and quality characteristics.

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Background: Plants possess a wide range of bioactive compounds with established health benefits which are highly susceptible to degradation. The environmental dynamics such as high temperature, light, oxygen limits the shelf life and bioavailability of these compounds in food and drug formulations. Encapsulation serves as an effective way of preserving these sensitive compounds by enclosing them within a coating/wall material and hence improves their bioavailability and functional properties. Scope and Approach: The wall materials used for encapsulation also known as encapsulants act as physical barriers between core compound and external stimuli. There are different edible protein, lipid and carbohydrate based encapsulants used for coating of bioactive compounds. However, this review gives a detailed insight on composition, functional properties, and applications of carbohydrate based polymers in food, and pharmaceutical industries while emphasizing on the advantages and limitations of these polymers in encapsulation process. So, we explored recent expansion in the area of natural polysaccharides and their derivatives as carriers for the targeted and sustained delivery of active compounds. Key Findings and Conclusions: Polysaccharides, natural gums (Carrageenan, Alginate, Gum arabic, Guar gum, Gellan gum, Xanthan gum) and their derivatives are biodegradable polymers being used as sustained release carriers. They are more advantageous over lipid based and protein based carriers by virtue of their unique features such as thermo stability and versatility of interacting with a range of hydrophilic and hydrophobic compounds. Tailormade carriers made by structural modifications of the polysaccharides using physical, chemical and enzymatic reactions result in improved functional properties and hence widen their area of applications. [ABSTRACT FROM AUTHOR]

Abstract Two different types of cellulose nanocrystals, derived from water hyacinth fibers and microfibrillated cellulose (MFC), were prepared using an acid hydrolysis treatment. These cellulose nanocrystals (CNCs) were further used as barrier enhancing fillers for polyurethane (PU) blended with 25 wt% of poly(vinylidene dichloride) (PVDC). The aim of this study was to investigate the effects of types and concentration of CNCs on mechanical, optical and barrier properties of polymer composite films. The feasibility of applying the obtained composite films as an encapsulating material for enhancing the lifetime of dye sensitized solar cells (DSSC) was also of interest. The acid hydrolysis of the MFC-yielded rod-shaped cellulose nanocrystals (CNCm) while the acid-hydrolyzed water hyacinth led to a formation of spherical-shaped cellulose nanocrystals (CNCw). Regardless of the types of CNCs, the optical transparency of the composite films was maintained well above 60%. According to results in this study, the most efficient film with the lowest water vapor transmission rate of 0.0517 g m−2 day−1 was the PU/PVDC film reinforced with 0.1 wt% of CNCm. The encapsulants made from this composite could prolong the lifetime of the DSSC devices for up to 14 days, with the normalized PCE value of 0.78. Overall, this work showed that the considerations of the barrier properties of the polymer encapsulants alone are insufficient to ensure that the system would be effective. An interfacial adhesion between the encapsulants and the electrodes, as well as some side reactions between polymers and chemicals inside the fabricated cell, should also be taken into account.

Marine-based dietary oils (MDOs), which are naturally obtained from different sources, have been scientifically recommended as potent functional bioactives owing to their therapeutic biological activities; however, they have exhibited plenty of health benefits. Though they are very sensitive to light, temperature, moisture, and oxygen, as well as being chemically unstable and merely oxidized, this may limit their utilization in food and pharmaceutical products. Miro- and nanoencapsulation techniques are considered to be the most promising tactics for enhancing the original characteristics, physiochemical properties, and therapeutic effects of entrapped MDOs. This review focuses on the biomacromolecule-stabilized micro/nanocarriers encompassing a wide range of MDOs. The novel-equipped polysaccharides and protein-based micro/nanocarriers cover microemulsions, microcapsules, nanoemulsions, and nanoliposomes, which have been proven to be encouraging candidates for the entrapment of diverse kinds of MDOs. In addition, the current state-of-the-art loading of various MDOs through polysaccharide and protein-based micro/nanocarriers has been comprehensively discussed and tabulated in detail. Biomacromolecule-stabilized nanocarriers, particularly nanoemulsions and nanoliposomes, are addressed as propitious nanocargos for protection of MDOs in response to thought-provoking features as well as delivering the successful, meticulous release to the desired sites. Gastrointestinal fate (GF) of biopolymeric micro/nanocarriers is fundamentally based on their centrifugation, dimension, interfacial, and physical properties. The external surface of epithelial cells in the lumen is the main site where the absorption of lipid-based nanoparticles takes place. MDO-loaded micro- and nanocarriers with biological origins or structural modifications have shown some novel applications that could be used as future therapies for cardiovascular disorders, thanks to today's cutting-edge medical technology. In the future, further investigations are highly needed to open new horizons regarding the application of polysaccharide and protein-based micro/nanocarriers in food and beverage products with the possibility of commercialization in the near future for industrial use. [ABSTRACT FROM AUTHOR]

• Comparison of crystalline-Si PV systems from 2-different PV manufacturers. • Identification of degradation mechanisms associated with EVA. • Mechanisms of chemical degradation are presented associated with loss of performance. • Comparisons using EL and UV to highlight performance differences. This paper reports on a unique evaluation-opportunity for comparing modules from two-different manufacturers that were deployed for a long-period (~15 years) under similar circumstances: (a) for the same distributed, rural-power applications, (b) operating under the same climate-conditions and geographical area, (c) with devices manufactured and installed at the same time. But these modules had very different resulting observed changes in their operational and physical characteristics over their long field-exposures. The PV modules were dispersed in a tropical climate-zone (northern-region of Minas Gerais, Brazil). Visual inspections of the two-module sets concluded that one module source (SET A) had almost no encapsulant discoloration and few indications of delamination and corrosion. In contrast, the other module source (SET B) had significant yellowing/browning, widespread-areas of delamination, and fairly extensive interconnect-corrosion. The corresponding measured changes in the electrical characteristics were: SET A having average annual loss in power of 0.4–0.5%, and SET B with 2.3–3.7%/year over their installation times. Encapsulant discoloration and delamination provided the first clues to the measured differences in module performance and are attributed to the existing climate conditions of high-ultraviolet (UV) radiation exposures and high-ambient temperatures. The bases for the performance differences of these two module sets were examined using complementary electrical, physical and chemical characterization of the module materials. The primary goal of this paper is to identify the root causes for the degradation differences (one set meeting specifications, the other not), based upon the critical module materials properties/processing and climatic exposures. [ABSTRACT FROM AUTHOR]

This paper presents a plastic-encapsulated wireless sensor module (WSM), using commercial off-the-shelf components, which has been demonstrated to be reliable for 180 cycles in a medical steam sterilizer with an environment involving high-rate temperature, pressure, and humidity cycles up to 134 °C, 3 bar, 100% RH. The WSM continuously transmits temperature and pressure data from the sterilizer, allowing the quality of sterilization to be verified. Twelve WSMs were assembled and encapsulated with substrate material and encapsulant type as experimental variables. These samples were then stress tested over multiple sterilization cycles, with continuous wireless data collection, until failure. Scanning acoustic microscope analysis was carried out before and after the reliability testing in the steam sterilizer. The results demonstrate that, with appropriate choice of materials, the WSM can survive for 180 full-steam sterilization cycles without any electrical failure of the components or any deterioration in the package structure except for delamination between the substrate and the encapsulant that did not cause electrical failure. The overall results demonstrate the reliability of a plastic-encapsulated module in an exceptionally harsh use environment, the ability to steam sterilize a plastic-encapsulated module for medical applications, and the potential for using a plastic-encapsulated WSM for continuous, high-resolution sterilizer parameter monitoring as a replacement for the currently used color-change chemical and biological indicators. This is believed to be the first plastic-encapsulated WSM for monitoring of steam sterilizer parameters and the first plastic-encapsulated module of any sort, which is capable of surviving multiple steam sterilization cycles. [ABSTRACT FROM AUTHOR]

With the increased development of portable and handheld molecular spectrometers within recent years, new fields of applications have opened up, such as their use (i) for material identification of samples contained in large and non-portable components and (ii) the detection of material degradation effects and failures directly in the plant. The usability and transferability of well-established analytical characterization techniques, such as attenuated total reflection (ATR) Infrared (IR)-, Raman, and Near-Infrared (NIR)-spectroscopy as mobile devices for the in-field characterization of Photovoltaic (PV) modules, are described and discussed. Material identification of the polymeric compounds incorporated in the PV modules (encapsulants, backsheets) is often an important task, especially when degradation and failures occur. Whereas the knowledge of the bill of materials is one challenge, the detection of material degradation effects is another important issue. Both tasks can be solved nondestructively by the application of mobile spectrometers. Raman spectroscopy is the best-suited method for the identification of the encapsulant within the module (measurement through 3-mm glass), while NIR measurements allowed for the nondestructive determination of the composition of the multilayer backsheet. Surface degradation effects (e.g., oxidation, hydrolysis) are best detectable with IR-spectroscopy. The application of mobile devices allows for direct material analysis in the field without dismantling PV modules, transporting them to the lab, cutting them in smaller pieces, and analyzing them in conventional bench-top spectrometers.

This research work concerns the development of transparent barrier films based on ethylene vinyl acetate copolymer (EVA) reinforced with the acid functionalized graphene nanoplatelets (GNP). GNP was melt-compounded with EVA in a micro-compounder via two types of mixing schemes. The effect of concentration of GNP on the barrier, thermomechanical and optical properties of the EVA composite films were investigated. Water vapour transmission rate of the EVA film decreased by more than 70% after 0.001-0.01 wt% of the GNP was applied. The visible light transmittance in the range of 84-91% was maintained. SEM images showed a random distribution of GNP in the EVA matrix with intimate contact between phases. FTIR spectra imply a polar-polar interaction between the two materials. Tensile toughness of the composite films increased with the concentration of GNP. These demonstrated that the acid functionalized GNP is compatible with EVA. The degree of swelling of the cured EVA films also decreased with the GNP content. The above effects were less obvious when the mixing scheme was changed to the master-batch method. Finally, by applying the EVA/GNP film to encapsulate dye-sensitised solar cells, the lifetime of the device was prolonged by at least three weeks, with the normalised PCE value of 0.74. [ABSTRACT FROM AUTHOR]

In order to evaluate module materials, the maximum theoretical value of the photo-generated current density, was calculated. The calculation was performed for four different solar cells, a standard p-type, passivated emitter and rear contact (PERC), bifacial cell and interdigitated back contact (IBC) considering a solar spectrum of Atacama Desert, the transmittance of several glass-encapsulant-glass structures and quantum efficiency. Regarding the solar spectrum in Atacama, an average air mass (AM) at noon for this location averaged 1.17 and the photovoltaic (PV) modules tilt angle was 20°. When studying the impact of using glass and encapsulants combined with a solar cell under the same solar spectrum, ethylene vinyl acetate (EVA) with low ultraviolet (UV) cutoff led to the higher current density values, up to 2% higher with the IBC solar cell compared to the other solar cells. The highest current gain, when studying the impact of the two spectra in the 300–1200 nm wavelength range, was 7.4% for the IBC solar cell, obtained with a standard 3.2 mm glass, a thermoplastic material (TM) as encapsulant. Considering the UV part of the spectrum, the current gain was maximized with a glass with an anti reflection coating (ARC) combined with the TM encapsulant for the IBC solar cell (25%). A quantification of losses due to reflection in the glass and absorption in the encapsulant revealed that the glass with ARC and the TM encapsulant different than EVA led to the lowest reflection and absorption losses. In this case, the reflection and absorption came down to 4.8% and 0.9%, respectively, contrasting with the 7% and 2.8% loss produced with the standard glass and EVA encapsulants. [ABSTRACT FROM AUTHOR]

Polyethylene-based poly(ethylene-co-vinyl acetate) (EVA), polyolefin elastomer (POE), and thermoplastic polyolefin (TPO) are common polymer candidates for photovoltaic (PV) module encapsulants. The choice of encapsulant must be carefully considered in novel module designs, such as bifacial glass/glass laminates, to limit performance degradation through loss of optical transmittance, mechanical integrity, and corrosion—as well as potential-induced degradation. Encapsulant quality and resilience against environmental stressors are readily influenced by the additives in the encapsulant formulation. Here, we show that, the changes in optical transmittance after UV aging result from the discoloration caused by interactions between additives, and optical scattering from changes in the polymer crystal structure. We observed competing cross-linking and chain scission mechanisms, with their kinetics influenced by the presence of oxygen and elevated temperatures. Increasing chamber temperatures from 55 °C to 85 °C during the UV stress test amplified encapsulant discoloration and promoted polymer cross-linking, causing severe, irreversible damage that remains to be proven field relevant. Damp heat aging was found to be insufficient to produce significant encapsulant degradation; however, combining stress tests sequentially allowed detection of further degradation beyond the limitations of the damp heat test alone. Appropriate degradation screening methods are necessary to uncover potential encapsulant weaknesses. • PV encapsulant aging causes changes in crystallinity resulting in optical scattering. • Sequential aging provides more realistic degradation than DH and UV tests alone. • TPOs suffer from irreversible cross-linking under UV and heat. • Encapsulant additive formulation has greater influence on durability than type of polymer resin. [ABSTRACT FROM AUTHOR]

Medical steam sterilizers use rapid cycles of temperature, humidity, and pressure to sterilize medical instruments. These cycles represent an exceptionally harsh environment for electronics and, currently, only metal can devices with high-reliability electronic components can be used to electronically monitor and verify the completeness of sterilization. The work presented in this paper has allowed the identification of a material set that allows plastic-encapsulated electronic modules with commercial-off-the-shelf electronic components and sensors, assembled on organic circuit boards, to survive over 100 sterilization cycles. In the course of the work, the failure mechanisms of the plastic-encapsulated modules and the deterioration of encapsulant adhesion over multiple sterilization cycles have been characterized. This opens the possibility of using plastic-encapsulated embedded electronics in smart medical and biomedical devices, which need resterilization after every use. [ABSTRACT FROM PUBLISHER]

Abstract: Synthetic polymers are used as encapsulants or front and back sheets in photovoltaic modules. Since the concentrations of (intact) stabilisers are crucial for the durability of the polymeric material, the current study provides methods for the determination of stabilisers in commercially relevant encapsulants for photovoltaic modules: ethylene vinyl acetate (EVA), polyvinyl butyral (PVB) and thermoplastic silicone elastomer (TPSE). For identification of the stabilisers present in EVA, direct analysis in real time coupled with mass spectrometry (DART-MS) is employed as a rapid method applicable to the polymeric film without sample preparation. For qualitative analysis of PVB and TPSE, but also for the subsequent quantification of the identified stabilisers in all investigated encapsulants, gas chromatography (GC) coupled with MS as well as high performance liquid chromatography (HPLC) coupled with UV and MS detectors are applied. Optimised protocols for the preparation of stabiliser extracts needed for these methods are presented for all three materials. [Copyright &y& Elsevier]

Abstract: Minimizing the optical and electrical losses from cell to module is essential for highly efficient PV modules. We use metal wrap through (MWT) solar cells with passivated rear surface to integrate them into a PV-module and minimize the cell to module losses. For this purpose, we analyze the optical properties of different encapsulation materials with respect to this specific cell type, i.e. the absorption losses in the encapsulants and coupling gains from refractive index. The best performing encapsulant shows a cell-to-module power loss of 0% for a 16-cell MWT module. The fill factor loss is 1.4% absolute. We reach a module efficiency of 17.4% on the aperture area implying a CTM-loss in efficiency of only 0.5% absolute. [Copyright &y& Elsevier]

Abstract: Encapsulation materials are very vital to the power light emitting diode packaging and become a hot topic for worldwide researchers because the devices packaging and assembly yield, and the devices reliability and lifespan are determined by the quality of packaging and assembly materials as well as their processing. In this paper, the functions requirements and properties of power LED packaging materials were introduced. In addition, the research progress on traditional LED packaging materials, especially high refractive index silicone encapsulants were discussed in detail. Meanwhile, the direction of further development of encapsulation materials was pointed out. [Copyright &y& Elsevier]

Abstract: We compare the properties of a number of encapsulant and soft backsheet materials that are important for photovoltaic (PV) module packaging. These properties include moisture transport and interfacial adhesion as a function of accelerated exposure to damp heat. Various cleaning and priming methods were studied for improving adhesion to glass and polymer surfaces. Barrier coatings prepared by industry and at NREL have been found to promote adhesion and provide varying levels of moisture-ingress protection. Plasma pre-etch of polyethylene terephthalate (PET) before barrier deposition reduces adhesion strength and moisture barrier properties. Resistance to cracking during lamination and peeling during test are investigated. The relative effectiveness of various combined packaging strategies to protect PV devices has been studied using 80-nm-thick aluminum films deposited onto 10cm×10cm glass substrates. Glass/ethylene vinyl acetate (EVA)/aluminized-glass laminate constructions were found to trap harmful compounds that catalyzed moisture-driven corrosion of Al. Constructions with breathable backsheets allow higher rates of moisture ingress, but also allow egress of deleterious substances, thereby reducing corrosion. [Copyright &y& Elsevier]

The optical transmittance properties, under diffuse light, of semitransparent materials used to fabricate photovoltaic devices have been investigated by using an apparatus provided with two “coupled” integrating spheres, one for producing the incident diffuse light and the other for collecting the transmitted light. A detailed analysis of the measurement conditions has been performed taking into account the perturbing effect each sphere produces on the other, and a final expression for the correct transmittance of the sample is derived. [Copyright &y& Elsevier]

With the increased development of portable and handheld molecular spectrometers within recent years, new fields of applications have opened up, such as their use (i) for material identification of samples contained in large and non-portable components and (ii) the detection of material degradation effects and failures directly in the plant. The usability and transferability of well-established analytical characterization techniques, such as attenuated total reflection (ATR) Infrared (IR)-, Raman, and Near-Infrared (NIR)-spectroscopy as mobile devices for the in-field characterization of Photovoltaic (PV) modules, are described and discussed. Material identification of the polymeric compounds incorporated in the PV modules (encapsulants, backsheets) is often an important task, especially when degradation and failures occur. Whereas the knowledge of the bill of materials is one challenge, the detection of material degradation effects is another important issue. Both tasks can be solved nondestructively by the application of mobile spectrometers. Raman spectroscopy is the best-suited method for the identification of the encapsulant within the module (measurement through 3-mm glass), while NIR measurements allowed for the nondestructive determination of the composition of the multilayer backsheet. Surface degradation effects (e.g., oxidation, hydrolysis) are best detectable with IR-spectroscopy. The application of mobile devices allows for direct material analysis in the field without dismantling PV modules, transporting them to the lab, cutting them in smaller pieces, and analyzing them in conventional bench-top spectrometers. [ABSTRACT FROM AUTHOR]

Carotenoids retain plenty of health benefits and attracting much attention recently, but they have less resistance to processing stresses, easily oxidized and chemically unstable. Additionally, their application in food and pharmaceuticals are restricted due to some limitations such as poor bioavailability, less solubility and quick release. Nanoencapsulation techniques can be used to protect the carotenoids and to uphold their original characteristics during processing, storage and digestion, improve their physiochemical properties and enhance their health promoting effects. The importance of nanocarriers in foods and pharmaceuticals cannot be denied. This review comprehensively covers recent advances in nanoencapsulation of carotenoids with biopolymeric nanocarriers (polysaccharides and proteins), and lipid-based nanocarriers, their functionalities, aptness and innovative developments in preparation strategies. Furthermore, the present state of the art encapsulation of different carotenoids via biopolymeric and lipid-based nanocarriers have been enclosed and tabulated well. Nanoencapsulation has a vast range of applications for protection of carotenoids. Polysaccharides in combination with different proteins can offer a great avenue to achieve the desired formulation for encapsulation of carotenoids by using different nanoencapsulation strategies. In terms of lipid based nanocarriers, solid lipid nanoparticles and nanostructure lipid carriers are proving as the encouraging candidates for entrapment of carotenoids. Additionally, nanoliposomes and nanoemulsion are also promising and novel-vehicles for the protection of carotenoids against challenging aspects as well as offering an effectual controlled release on the targeted sites. In the future, further studies could be conducted for exploring the application of nanoencapsulated systems in food and gastrointestinal tract (GIT) for industrial applications. Schematic illustration of niosomes loaded with carotenoids. Unlabelled Image • Application of carotenoids is limited due to poor bioavailability, low solubility and quick release. • Nanocarriers can be used to protect carotenoids during processing, storage and digestion. • This review covers nanoencapsulation of carotenoids with biopolymeric and lipid nanocarriers • GIT fate of carotenoid-loaded nanocarriers has also been discussed. [ABSTRACT FROM AUTHOR]

Two different types of cellulose nanocrystals, derived from water hyacinth fibers and microfibrillated cellulose (MFC), were prepared using an acid hydrolysis treatment. These cellulose nanocrystals (CNCs) were further used as barrier enhancing fillers for polyurethane (PU) blended with 25 wt% of poly(vinylidene dichloride) (PVDC). The aim of this study was to investigate the effects of types and concentration of CNCs on mechanical, optical and barrier properties of polymer composite films. The feasibility of applying the obtained composite films as an encapsulating material for enhancing the lifetime of dye sensitized solar cells (DSSC) was also of interest. The acid hydrolysis of the MFC-yielded rod-shaped cellulose nanocrystals (CNCm) while the acid-hydrolyzed water hyacinth led to a formation of spherical-shaped cellulose nanocrystals (CNCw). Regardless of the types of CNCs, the optical transparency of the composite films was maintained well above 60%. According to results in this study, the most efficient film with the lowest water vapor transmission rate of 0.0517 g m−2 day−1 was the PU/PVDC film reinforced with 0.1 wt% of CNCm. The encapsulants made from this composite could prolong the lifetime of the DSSC devices for up to 14 days, with the normalized PCE value of 0.78. Overall, this work showed that the considerations of the barrier properties of the polymer encapsulants alone are insufficient to ensure that the system would be effective. An interfacial adhesion between the encapsulants and the electrodes, as well as some side reactions between polymers and chemicals inside the fabricated cell, should also be taken into account. [ABSTRACT FROM AUTHOR]