Clean Materials Research Articles

Gas sensitivity evaluation of decomposition gases in environmentally friendly insulating devices (C4F7N/CO2) (Chromium cluster-modified BNNTs surface interface at the atomic scale)

Under the global trend of green development, the research and development of environmentally friendly gas-insulated electrical equipment and the associated technical issues in the power systems industry have become important research topics. This study investigates the monitoring technology for decomposition gases (CO, C2F6, and COF2) under insulation defect conditions in environmentally friendly GIS equipment based on the green insulating gas mixture C4F7N/CO2. Initially, chromium clusters (Crn, n = 1–4) were used to modify one-dimensional boron nitride nanotubes (BNNTs), describing the changes in semiconductor electronic properties and magnetism at the microscopic interface. Interestingly, the electronic properties of the system changed significantly after modification, with increased electron mobility and enhanced conductivity. Subsequently, adsorption tests were conducted on three potential target gases, revealing that Cr-BNNT exhibited excellent adsorption for COF2, with an adsorption energy reaching -9.555 eV. This indicates its potential as a clean material for addressing COF2 (toxic) and CO leaks. Lastly, and most importantly, in the assessment of sensing performance, it has been discovered that Cr-BNNT holds promise as a gas sensor for C2F6. Furthermore, to meet diverse sensing requirements and environmental conditions, Cr3-BNNT and Cr4-BNNT have demonstrated potential as sensor array materials for the detection of CO (300 K, 0.145 μs) and COF2 (500 K, 3 min) gas concentrations, respectively. Our study contributes to the advancement of novel eco-friendly insulating gases and explores the use of new materials for monitoring the insulation performance and condition assessment of environmentally friendly GIS equipment.

Bioderived carbon aerogels loaded with g-C3N4 and their high Efficacy removing volatile organic compounds (VOCs)

Indoor air pollution, predominantly caused by volatile organic compounds (VOCs), poses significant health hazards when concentrations surpass critical thresholds. Using waste corn straw as carbon source and urea as nitrogen source, straw derived carbon aerogel (CAGH) loaded with g-C3N4H2O-N2-450–3 h was successfully prepared by hydrothermal and water-assisted calcination. Following water-assisted regulation, g-C3N4H2O-N2-450–3 h on CAGH exhibited a mixed structure comprising honeycomb and two-dimensional filaments, while the growth of g-C3N4H2O-N2-450–3 h was uniformly distributed on carbon aerogel in a line-surface combination fashion. This innovative binding method not only enhanced the loading capacity of g-C3N4 and the mechanical elasticity of aerogel, but also exposed a large number of adsorption sites, resulting in a significant increase in its adsorption capacity for VOCs, exceeding that of commercial activated carbon (AC). In comparison to pure g-C3N4, CAGH exhibited an expanded photo-response range. Under the exposure of visible light, CAGH proved highly effective in eliminating 73.87 % of toluene. In addition, it has demonstrated efficient removal of formaldehyde and acetone VOCs with good cyclic stability. Therefore, this work aims to reduce the emission of pollutants at source and provide an effective and economical strategy for the preparation of clean building materials from renewable materials, with potential applications in the environmental field.

Tartrate‐Anchored Tetranuclear Titanium‐Oxo Clusters Functionalized by Chromophore Ligands Exhibiting Photoelectric Response and Photodegradation Performances of Methylene Blue

ABSTRACTIn recent years, researchers have devoted considerable effort to the study of high crystalline titanium‐oxo clusters (TOCs), because TOCs are considered to be the molecular analogs of TiO2 nanoparticles and have the potential to be utilized as effective cleaning and catalytic materials. Two new tartrate‐anchored tetranuclear TOCs functionalized with chromophore ligand of p‐nitrobenzoate (NB)/p‐toluenesulfonate (TS), namely, [Ti4(TA)(NB)2(OiPr)10] (1, H4TA = tartaric acid) and [Ti4(TA)(TS)2(OiPr)10] (2), were synthesized and their structures were characterized by various methods. The molecular structure analyses indicated that 1 and 2 are all tetranuclear {Ti4} TOCs, in which tartrate appears as a hexadentate μ4‐bridging ligand while p‐nitrobenzoate/p‐toluenesulfonate acts as a bidentate μ2‐bridging ligand. TOCs 1 and 2 are of good thermal and solvent stability. Furthermore, their photocurrent responses and photocatalytic degradation activities towards methylene blue (MB) were also investigated. In the presence of H2O2, the photocatalytic degradation efficiencies of MB by 1 and 2 are about 84.43% and 71.00%, respectively, at room temperature under visible light irradiation for 60 min. These findings shed light on designing efficient polycarboxylate‐based TOCs photocatalysts.

A global fairtrade partnership needed to address injustices in the supply chains of clean energy technology materials

Abstract Renewable sources produced close to one-third of the world’s electricity in 2023. However, a limited but growing body of research suggests rapid renewable energy development is leading to conflict and resource exploitation in energy-transitioning communities. Such injustices are attributable to the extractivist nature of renewable energy development, where raw materials, also known as Clean Energy Technology Materials (CETMs), are in limited quantities and often concentrated in resource-constrained zones in the Global South. In this perspective, we call for an urgent need for energy justice considerations in CETM’s supply chain. We used demand projection data from 2020 to 2040 to look into the effects of important CETMs like nickel, cobalt, and lithium on distributive justice. We also examined the potential of these effects to tackle systemic injustices such as conflict, labor exploitation, and transactional colonialism. Next, we analyzed global mining production data from the United States Geological Survey using a CETM life cycle lens and found that increasing demand for these materials is exacerbating restorative injustices, particularly in the Global South. Finally, building on the above evidence, we called for the creation of multi-stakeholder partnerships and the establishment of fair trade standards across the critical CETM supply chain. Graphical abstract Highlights Here, we analyzed the projected demand growth for selected clean energy technology materials by 2040 relative to 2020 levels using data from the International Energy Agency, visualized their global mining production using data from the United States Geological Survey, explained how the demand for these materials is exacerbating certain injustices, and recommended multi-stakeholder partnerships across the supply chain of these materials. Discussion The rapid growth of renewable energy technologies is creating injustices throughout the supply chain of clean energy technology materials (CETM). A lack of any energy justice framework across CETMs’ extraction, processing, decommissioning, and recycling is exacerbating restorative injustices, especially in the Global South. By examining the projected demands and geospatial patterns for the extraction of minerals, metals, and other materials essential for clean energy technology development, the inequities faced by impoverished, marginalized, and Indigenous communities become apparent. We argue that if coffee can have fair trade standards across its supply chain, why can’t we have similar considerations for the CETMs? There is a need to include transparency in the sustainability, ethics, and energy efficiency of CETM extraction and processing through global partnerships across its supply chain.

Crystallization of Bis(2-hydroxyethylene) Terephthalate as a Part of a Bottle-to-Bottle Recycling Concept for Poly(ethylene terephthalate).

The chemical recycling of poly(ethylene terephthalate) (PET) is very attractive as PET bottle waste provides an abundant clean material with low levels of additives. One of the most promising processes is glycolysis, which depolymerizes PET in the presence of ethylene glycol. For this process, it is necessary to think through the whole concept, from the waste material to the newly polymerized virgin polymer. Most research ends with determining the yield of bis(2-hydroxyethyl)terephthalate (BHET) after glycolysis. Some research includes antisolvent crystallization with water to separate BHET from ethylene glycol. However, the subsequent separation of water and ethylene glycol is an energy-intensive process. Therefore, this work aims to directly crystallize BHET from ethylene glycol. For this reason, the crystallization of BHET was investigated experimentally. Crystallization was simulated using gPROMS Formulated Products with the aim of estimating kinetic parameters and using these to optimize an industrial process. Kinetic parameters were determined by model validation, including primary and secondary nucleation and crystal growth. The best-fitting set of kinetic parameters was used to optimize BHET crystallization in batch and continuous modes by minimizing equipment costs. Impeller parameters were found to have a great influence on crystallization performance. Ultimately, the continuous and batch processes gave comparable results in terms of equipment cost, with the batch process giving larger crystals and higher yields but the continuous process requiring a smaller crystallizer.

Investigation of the Impact of Single and Double Filtration Systems on Post-Consumer PE Film Waste.

Due to the diversity of plastic film waste streams available on the market and the associated variety of contaminants' size and number, the use of melt filtration is necessary. Currently, single and double filtration systems are state of the art in the plastic recycling industry, depending on the application of the produced post-consumer recyclate (PCR). Using PCR for thin films demands small contamination sizes, which are easier to reach using a second filtration step. In the case of relatively clean post-consumer input materials, it must be investigated whether the additional load from the second filter has a counterproductive effect on the material and whether single filtration would be sufficient. For this paper, polyethylene (PE) film waste stemming from a separate post-consumer collection in Austria was processed using an industrial-sized recycling machine with different combinations of filter sizes and systems. Melt flow rate (MFR), ash content, oxidation onset temperature (OOT), and optical contaminant detection were measured to investigate the influence of single and double filtration systems. The investigation showed that, even though the contamination amount and size were reduced, the second filter had a distinct effect on specific properties.

3D-printing inherently MRI-visible accessories in aiding MRI-guided biopsies

Background3D printers have gained prominence in rapid prototyping and viable in creating dimensionally accurate objects that are both safe within a Magnetic Resonance Imaging (MRI) environment and visible in MRI scans. A challenge when making MRI-visible objects using 3D printing is that hard plastics are invisible in standard MRI scans, while fluids are not. So typically, a hollow object will be printed and filled with a liquid that will be visible in MRI scans. This poses an engineering challenge however since objects created using traditional Fused Deposition Modeling (FDM) 3D-printing techniques are prone to leakage. Digital Light Processing (DLP) is a relatively modern and affordable 3D-printing technique using UV-hardened resin, capable of creating objects that are inherently liquid-tight. When printing hollow parts using DLP printers, one typically requires adding drainage holes for uncured liquid resin to escape during the printing process. If this is not done liquid resin will remain inside the object, which in our application is the desired outcome.PurposeWe devised a method to produce an inherently MRI-visible accessory using DLP technology with low dimensional tolerance to facilitate MRI-guided breast biopsies.MethodsBy hollowing out the object without adding drainage holes and tuning printing parameters such as z-lift distance to retain as much uncured liquid resin inside as possible through surface tension, objects that are inherently visible in MRI scans can be created without further post-processing treatment.ResultsObjects created through our method are simple and inexpensive to recreate, have minimal manufacturing steps, and are shown to be dimensionally exact and inherently MRI visible to be directly used in various applications without further treatment.ConclusionOur proposed method of manufacturing objects that are inherently both MRI safe, and MRI visible. The proposed process is simple and does not require additional materials and tools beyond a DLP 3D-printer. With only an inexpensive DLP 3D-printer kit and basic cleaning and sanitation materials found in the hospital, we have demonstrated the viability of our process by successfully creating an object containing fine structures with low spatial tolerances used for MRI-guided breast biopsies.

Flotation of ultra-low ash coal combined with ultrasonic pretreatment

ABSTRACT Ultra-low ash coal is an essential clean energy and material. The preparation of ultra-low ash coal by flotation is facing challenges due to the inherent drawbacks. This work aims to enhance the flotation efficiency of ultra-low ash coal by ultrasonic pretreatment. Timed-release flotation experiments were conducted with ultrasonic pretreatment before and after collector addition. The results showed that the recovery and combustible recovery and flotation perfect index of clean coal increased after ultrasonic pretreatment. Additionally, the flotation circuits can reduce from three to two times to obtain clean coal with ash content around 5%. The particle size distribution of coal varied from unimodal to bimodal after ultrasonic pretreatment no matter whether collector was added, indicating that ultrasonic had both dispersing and flocculation effects. Scanning electron microscope (SEM) analysis illustrated that the surface of coal was cleaned due to the ultra-fine gangue particles coated on coal surface was dispersed, and the flocculation of low-ash coal particles was promoted after ultrasonic pretreatment. Consequently, the ultra-low ash coal with higher recovery and quality could be obtained with simplified circuits.

Micropropagation and cryopreservation of the rare endemic Colchicum figlalii germplasm

BACKGROUND: The natural population of Colchicum figlalii (Varol) Parolly & Eren grows in a narrow area of serpentine rock clearings at an altitude of 1900-2100 m in Southwestern Anatolia (Sandras Mountain, Mugla, Turkey). The species is regarded as endangered according to the IUCN Red List Categories. OBJECTIVE: To develop an optimum procedure for in vitro propagation and cryopreservation of germplasm of this rare endemic. MATERIALS AND METHODS: A total of 281 bulbs were used as in vitro culture starting material and after surface sterilization, clean material was obtained from 157 of them. Woody Plant Medium (WPM), Olive Medium (OM), and Murashige and Skoog medium (MS) were used for in vitro culture establishment. RESULTS: The maximum regeneration rate (˜67.3%) was obtained after four weeks of incubation on OM. The calli were successfully induced by using OM supplemented with 10.7 μM NAA from leaves of in vitro grown C. figlalii bulbs. A PVS2-vitrification procedure was used for cryopreservation of C. figlalii callus tissue. After cryo-storage, the best result for regeneration (66.7%) was obtained from calli treated with PVS2 for 75 min before plunging into liquid nitrogen. All rooted seedlings derived from cryopreserved calli were successfully acclimatized to greenhouse conditions. CONCLUSION: This study is an effective reference for future long-term conservation of similar species that are difficult to cryopreserve.

Hydrogel Extinguishants.

The exploitation of clean and efficient fire extinguishing materials has substantial implications for improving disaster prevention, mitigation, and relief capabilities, maintaining public safety, and protecting people's lives and property as well as the natural environment. Natural polymer hydrogel with high water containment, excellent film formation, high heat insulation, ecofriendliness, and degradability has huge potential in achieving new breakthroughs for developing clean and efficient fire extinguishing materials and products. In recent years, the exploitation of hydrogel extinguishing materials and the fabrication of products has attracted great attention, gradually replacing traditional fire extinguishing products. In this perspective, an in-depth review of the evolution of hydrogels applied for fire extinguishing and prevention is presented. Firstly, the extinguishing principles of hydrogel extinguishants are explained. Secondly, the preparation strategies and evaluation system of the hydrogel extinguishants are emphatically discussed. Although great progress has been made in developing high-performance hydrogel extinguishants, it remains challenging to develop cost-effective, degradable, and easy-to-use hydrogel extinguishants. Additionally, we highlight the importance of considering the commercial aspects of hydrogel extinguishants. Looking into the future, hydrogel extinguishants are promising, but continued investment in research and development is necessary to overcome the challenges.

Huge Electron Sponge of Polyoxometalate toward Advanced Lithium-Ion Storage.

The huge polyoxometalate, ({Mo368}), which can be prepared by a facile solution process and can be applied in lithium-ion storage applications as the anode. The large and open hollow nanostructure is promising to store a larger number of lithium ions and expedite the diffusion of lithium ions. A single {Mo368} nanocluster can transfer 624 electrons, referred to as a "huge electron sponge". Pure {Mo368} without any support materials exhibits very high capacities of 964 mA h g-1 with hardly any decay for 100 cycles at 0.1 A g-1 and still maintains 761 mA h g-1 after 180 cycles at 0.5 A g-1, indicating great cycling stability. The {Mo368} anode provides excellent rate performance and reversibility during the lithiation/delithiation processes, which are contributed by both the diffusion-controlled process and the capacitive process. The capacitive contribution can reach 71.7% at a scan rate of 2 mV s-1. The high DLi+ value measured by GITT confirms the fast reaction kinetics of the {Mo368} electrode. The {Mo368}//NCM111-A full cell is practically applied to light LED lamps. These investigations indicate that {Mo368} nanoclusters are advanced energy storage materials with high capacities, fast charge transfer, and low-cost mass production for lithium-ion storage. Moreover, {Mo368} should be considered a clean energy material because there is no production of environmental pollution during the charge/discharge processes.

The acceptance of biogas in Islamic Boarding School Surakarta

The rapid population growth in Indonesia is leading to increased energy demands and the depletion of global energy sources. One promising to meet these escalating energy needs in the adoption of renewable energy sources like biogas. This study employs qualitative research methods to measure the response of the Islamic boarding school community in Central Java towards biogas utilization. Data analysis was conducted interactively, narratively describing insights gleaned from questionnaires completed by respondents. The findings reveal a varied response within Central Java Islamic Boarding School Community towards embracing biogas as part of efforts to enhance the national renewable energy mix. However, there is a consensus on certain aspects: respondents generally support biogas utilization as long as it is safe, sourced from clean materials, and developed in suitable locations. The exploration among ten boarding schools suggests that the government’s renewable energy initiatives require further optimization in terms of socialization and engagement with Islamic boarding schools.

Cu-MOF modified ZnIn2S4 nanosheet composite catalyst for photocatalytic hydrogen production

In the realm of photocatalysis, the creation of clean and pollution-free composite material catalysts is critical. Electrostatic self-assembly techniques were used in this study to construct ZnIn2S4 nanosheets onto the surface of Cu-MOF, culminating in the development of a unique Cu-MOF/ZnIn2S4 composite catalyst. Cu-MOF was shown to have a strong interface impact with ZnIn2S4, which resulted in a large increase in the number of active sites and, consequently, the efficiency of hydrogen generation. This was demonstrated by a number of parameters. The Cu-MOF/ZnIn2S4-10 composite material's optimum hydrogen evolution rate was 0.3 mmol h−1g−1, which was 2.14 times larger than that of pure ZnIn2S4 nanosheets (0.14 mmol h−1g−1). Furthermore, the development of Cu-MOF/ZnIn2S4 heterojunctions considerably improved ZnIn2S4's deficiencies in photocatalytic hydrogen production, increasing charge separation rates and providing a viable approach to improve ZnIn2S4's hydrogen production efficiency.

Regulating sulfur migration and transformation in low water-binder ratio cementitious system incorporating phosphogypsum aggregate: Environmentally friendly clean materials

The paper aims to clarify the regulation mechanism of sulfur migration and transformation in a low water-binder ratio system incorporating phosphogypsum aggregate (LWC-PG). Firstly, the combination of S-containing adhesive material and phosphate gypsum aggregate can reduce the migration of sulfate ions (SO42−) in the phosphate gypsum aggregate. The reaction mechanism and macro and micro properties of LWC-PG are characterized by universal testing machine, low field nuclear magnetic field, isothermal calorimeter, XRD diffractometer, scanning electron microscope and nano-indentation. The results show that the calcium sulfoaluminate cementitious system (CSA) is compatible with PG. The results show that CSA is compatible with PG, and the 28d strength of 80 % phosphogypsum is 83.4 MPa, which can maintain the required strength for high-performance concrete. Secondly, the sulfides in PG react with C4A6S in CSA, resulting in the formation of ettringite that coats the surface of the C–S–H gel, thereby retarding the hydration rate of the slurry. However, due to the presence of phosphate gypsum aggregate, the reaction continues, enhancing the hydration of sulfate cement. Moreover, the interfacial transition zone between the PG and matrix exhibits a strong bond and shows no significant signs of deterioration. Lastly, when using 80 % phosphogypsum aggregate instead of natural sand and gravel to produce 100 m3 of concrete, 42 t of phosphogypsum aggregate can be used, which reduces the consumption of natural sand and gravel by 61.4 t, decreases energy consumption by 3070 MJ, reduces CO2 emissions by 178.06 kg, SO2 emissions by 0.37 kg, NOX emissions by 0.25 kg, and dust emissions by 0.087 kg. Life cycle evaluation demonstrates that the production of LWC-PG is associated with low carbon emissions and environmental friendliness, which significantly reduces environmental burden. This is of significant research importance for solid waste management and energy-saving and carbon reduction efforts.

Increased farmer willingness to pay for quality cassava (Manihot esculenta Crantz) planting materials: evidence from experimental auctions in Cambodia and Lao PDR

AbstractVarietal turnover is a major mechanism for farmer adaptation to rapidly changing environmental and market conditions. Understanding factors related to varietal turnover is critical for safeguarding food security in the face of increasingly rapid changes to production contexts. Preference elicitation methods like experimental auctions reveal farmers’ willingness to pay (WTP) for seeds with different characteristics. We engaged farmers growing cassava (Manihot esculenta Crantz) across a wide geographic scope in Cambodia (n = 321, 4 provinces) and Lao PDR (n = 391, 5 provinces) in modified second-price experimental auctions to determine WTP for three cassava seed classes: farmer-produced planting stems of an undescribed variety, farmer-produced planting stems of an elite variety with lower susceptibility to Cassava Mosaic Disease (CMD), and virus-free tested planting stems of the same elite variety. In Lao PDR, mean auction bids for a bundle of 20 planting stems were 0.54, 0.92, and 1.40 USD for farmer, elite, and elite tested stems, while in Cambodia the analogous mean bids were 0.58, 0.77, and 1.16 USD, respectively. A significantly higher WTP associated with elite variety and tested stems in both countries was influenced by both geographic location (province) and individual socioeconomic farmer characteristics. In Lao PDR this included lower WTP of women, higher WTP of ethnic minorities, and, for improved stems, lower WTP of farmers with increased cassava growing experience. In Cambodia fewer socioeconomic variables affected WTP. Our results indicate significant increases in WTP for clean planting materials and new varieties, supporting market-based clean seed approaches as a component of regional control strategies for the CMD epidemic currently threatening a global agri-food value chain.

Tracking Sweet Potato Leaf Curl Virus through Field Production: Implications for Sustainable Sweetpotato Production and Breeding Practices.

Sweet potato leaf curl virus (SPLCV) is a whitefly-transmitted begomovirus infecting sweetpotato and other morning glory (Convolvulaceae) species worldwide. The virus is widespread at the USDA, ARS, U.S. Vegetable Laboratory (USVL), and testing of germplasm maintained in the breeding program indicates nearly 100% infection in storage roots of materials propagated for at least four years. Prior to the public release of new germplasm, viruses must be eliminated via laborious and time-consuming meristem-tip culture. The identification of virus-free seedlings early in the selection process can offer an alternative to meristem-tip culture. In this study, we investigated the transmission of SPLCV over two years of consecutive field plantings (early and late) of sweetpotato. While SPLCV is endemic at the USVL, virus transmission pressure over the typical cultivation season is unknown, and avoidance of virus transmission paired with the selection and maintenance of clean material may be a viable alternative to virus elimination. In 2022, the storage roots of 39 first-year seedling (FYS) selections were tested for SPLCV after early-season cultivation, revealing a single selection (2.6%) with a positive test. Similar testing was conducted in 2023 with no SPLCV-positive FYS selections detected. To further assess SPLCV acquisition in the field, replicated late-season plantings of each selected FYS (n = 37) were monitored from planting to harvest. Testing was conducted at 60 and 120 days after planting (DAP). Approximately 35% of the bulk samples were infected at 60 DAP, and infection increased to 52.3% by 120 DAP. Testing of individuals within selected positive bulked samples did not support 100% infection at harvest. Altogether, these results demonstrate that SPLCV transmission during early planting is sufficiently low to facilitate the maintenance of virus-free selections, offering an alternative to virus cleaning and a cultivation strategy that may be leveraged for production.

Salmonella and Listeria monocytogenes Survival on Field Packed Cantaloupe Contact Surfaces

Field-packing of cantaloupes involves numerous food contact surfaces that can contamination melons with foodborne pathogens; the soil on these surfaces increases throughout the harvest day. Data are lacking on the cross-contamination risk from contaminated food contact surfaces under the dry conditions typical of cantaloupe field-packing operations. This study sought to evaluate the survival of Salmonella and Listeria monocytogenes on cantaloupe field-pack food contact surfaces using both a wet and dry inoculum to provide insights into managing foodborne pathogen contamination risks. Five clean or fouled materials (cotton gloves, nitrile gloves, rubber gloves, cotton rags, and stainless steel) were inoculated with a cocktail of either Salmonella or L. monocytogenes. A wet inoculum was spot inoculated (100 µL) onto coupons. A dry inoculum was prepared by mixing wet inoculum with 100 g of sterile sand and shaking the coupons with the inoculated sand for 2 min. Coupons were held at 35°C (35% RH) and enumerated at 0, 2, 4, 6, and 8 h. Significant differences in pathogen concentrations over time were calculated, and the GInaFiT add-in tool for Excel was used to build Log-linear, Weibull, and Biphasic die-off models. Depending on the material type, coupon condition, and inoculum type, Salmonella and L. monocytogenes reductions over 8 h ranged from 0.3 to 3.3 and −0.4 to 4.2 log10 CFU/coupon, respectively. For all material types, Salmonella reductions were highest on wet-inoculated clean coupons; L. monocytogenes varied by material type. Weibull and biphasic models were a better fit of respective pathogen die-off curves than linear models. Overall, faster die-off rates were seen for wet inoculated and clean materials. Since pathogen populations remained viable over the study duration and both inoculum type and coupon condition impacted survival, frequent sanitation or replacement of food contact surfaces during the operational day is needed to reduce the risk of cross-contamination.

“Twin Chain” PVA Cryogels with Controlled Tortuosity as Advanced Materials for Cleaning of Works of Art

AbstractSoft matrices with tuned properties are part of the vast landscape of innovative materials for the restoration of works of art. “Twin chain” polymer networks (TC‐PNs) based on polyvinyl alcohol have proven unique as scaffolds for Cultural Heritage cleaning. They enable optimum adaptability, adhesion, porosity, and connectivity at both micro‐ and nano‐scale resulting in superior time/space‐controlled cleaning operations. In this work, TC‐PNs properties are tuned through a mild crosslinking of the poly(vinyl alcohol) (PVA)‐porogen polymer by using sebacic, adipic, or succinic acid. The modified porogens have different structural features imparting a different phase behavior to TC‐PVAs mixtures in aqueous solution, i.e., in pre‐gel systems used to form gels through a liquid–liquid phase separation. The macro‐, micro‐, and nanoscale features of the final gels are characterized by Confocal Laser Scanning Microscopy, Small Angle X‐ray Scattering, Rheology and are related to their cleaning performances. The study shows that the gels cleaning capacity is related to their tortuosity, that can be tailored at the nanoscale. Counterintuitively gels with higher tortuosity show better performances as evidenced by the cleaning of mockups and paintings from Jean Helion, Jackson Pollock, and Tancredi Parmeggiani at Peggy Guggenheim Collection in Venice.

IJCM_60A: Menstrual hygiene management practices in tribal areas of Mysore district: A cross-sectional study

Background: Menstrual Health Management is defined as women and adolescent girls using a clean menstrual management material to absorb or collect blood that can be changed in privacy as often as necessary for the duration of menstruation period, using soap and water for washing the body as required and having access to facilities to dispose of menstrual management materials. Since considerable amount of tribal population belong to Mysore district it is important to study the practices among the most vulnerable population. Objectives: 1. To estimate the knowledge on menstrual hygiene among the study population. 2. To measure the impact of socio-demographic and cultural determinants on menstrual hygiene management practices among the study population. Methodology: A community based cross-sectional study on menstruating women residing in tribal areas of Mysuru district was conducted from July to September 2023. Sample size was calculated using single proportion formula and it was estimated to be 130. All menstruating women/girls who were present during the time of visit were included in the study after getting their consent/ ascent. Multistage sampling was adopted to select the study participants. A validated semi-structured questionnaire was used for collection of data. Data was entered in MS Excel and analysed using SPSS v29 trial version. Results: 99% of the study population knew that menstruation is a physiological process and poor menstrual hygiene causes urinary and reproductive tract infections. More than 80% of the study population have access to sanitary napkins for managing their menstrual cycles. Conclusion: Majority of the study participants are aware about menstruation as a physiological process and have access to sanitary napkins for management. But the disposal of sanitary waste and cultural barriers that persists in the society are still existing as a roadblock for improving reproductive health.

Toxicity test of mangosteen peel extract (Garcinia mangostana L.) as denture cleanser of heat-cured acrylic resin: in vitro experimental laboratory

ABSTRACTIntroduction: Mangosteen peel extract can be used as a denture cleaning agent to effectively inhibit the growth of C. albicans because mangosteen peel contains various compounds such as mangostin, tannins, flavonoids, saponins. Denture cleaning materials that will be used in the dental field must meet biocompatibility requirements, one of which is a toxicity test. The aim of this study was to analyze the toxicity of mangosteen peel extract as a cleaner of heat cured acrylic resin denture on BHK-21 as cell culture of fibroblast cells. Methods: Toxicity test used the MTT assay method. Acrylic resin samples had a diameter of 3 mm and a thickness of 2 mm. The acrylic resin was soaked for 4 days, equivalent to soaking 15 minutes per day for 1 year in mangosteen peel extract with concentrations of 50, 60, 70%, and sodium hypochlorite. Analyzed data using normality and homogeneity test results showed (p<0.05). Kruskal Wallis test results (0.000<0.05) and Mann Whitney (0.000<0.05). Results: The greatest cell viability value was shown in mangosteen peel extract with a concentration of 50%, namely 97.16939%. Based on research data, it can be said that the lower the concentration of mangosteen peel extract, the lower the level of toxicity of a denture cleanser agent. Mangosteen peel extract in concentrations of 60, 70%, and sodium hypochlorite are toxic when used as a denture cleanser. Conclusion: Mangosteen peel extract with a concentration of 50% is not toxic to BHK-21 fibroblast cells as cell culture of and as a cleaner of heat cured acrylic resin denture on.Keywordheat-cured acrylic resin, mangosteen peel extract, MTT assay.