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The development of new technologies leads to the extensive use of abiotic resources and possible disruptions in the supply of material due to political, economic, and environmental reasons. To understand the impact of such disruptions on the economy, a comprehensive criticality assessment is necessary. As Japan is the third largest economy globally and heavily reliant of imports, the criticality of abiotic resources might become a pressing issue. However, previous criticality assessments of Japan have been limited in scope, failing to assess the overall supply disruption risks. Thus, this paper aims at identifying critical aspects of 35 abiotic materials used in the Japanese economy using the SCARCE method – an approach considering supply risk, vulnerability, social and environmental aspects to comprehensively analyse criticality. In the context of supply risk and vulnerability, the minerals niobium and phosphorus have been identified as the most critical. The criticality of niobium can be attributed to its significant trade barriers and production concentration, while that of phosphorus is primarily influenced by its high demand and lack of substitutes. Gold is the material with the highest criticality from environmental point of view due to the environmental implications related to its production. In the social context, the most critical mineral is antimony due to high level of small-scale and artisanal mining. In addition to the Japanese criticality, the results reflect the global one, showing the materials globally less critical and thus especially relevant to the Japanese economy. Next to providing results of 35 materials for evaluating their role in the Japanese economy, the underlying Python code is provided for adaptation for further criticality assessments of other regions. Based on these results, specific resource management strategies can be developed for Japan to ensure the availability of essential abiotic resources for the Japanese economy. • Criticality assessment with a vast array of economic, environmental and social indicators. • Criticality assessment applied to the case study of Japan and transparent calculation methodology. • Platinum and lignite pose highest supply risk for Japan. Critical in terms of vulnerability are phosphorus and nickel. • The environmental and social hotspots for Japan are gold and antimony respectively. • Japanese and global criticality comparison highlights the importance of lignite, lithium, and nickel for Japan's economy. [ABSTRACT FROM AUTHOR]

Huge material stocks are embedded in the residential built environment. These materials have the potential to be a source of secondary materials, an important consideration for the transition towards a circular economy. Consistent information about such stocks, especially at the global level, is missing. This article attempts to fill part of that gap by compiling a material intensities database for different types of buildings and applying that data in the context of a scenario analysis, linked to the SSP scenarios as implemented in the global climate model IMAGE. The database is created on a global scale, dividing the world into 26 regions in compliance with IMAGE. The potential use of the database was tested and served as input for modelling the housing and material stock of residential buildings for the period 1970–2050, according to specifications made for the SSP2 scenario. Six construction materials in four different dwelling types in urban and rural areas are included. The material flows related to those stocks are estimated and analysed in a companion paper (also exploring commercial buildings) by Deetman et al. (2019). The results suggest a significant increase in the material stock in housing towards 2050, particularly in urban areas. The results reflect specific patterns in the material contents across the different building types. China presently dominates developments in the global level building stock. The SSP2 projections show a stock saturation towards 2050 for China. In other regions, such as India and South East Asia, stock growth is presently just taking off and can be expected to become dominant for global developments after 2050. The database is created to be used as input for resource and climate policymaking as well as assessment of environmental impact related to residential buildings and assessment of possibilities for urban mining. In the future, we hope to extend it as new data on materials in the built environment become available. [ABSTRACT FROM AUTHOR]

Residential buildings and service sector buildings have an important contribution to climate change, directly via energy use in these buildings and indirectly through construction activities and the production and disposal of buildings materials. In this paper, we introduce a model that looks at total global building stock for 26 regions between 1970 and 2050 and calculates the floor space and building materials both in new buildings and in demolished buildings. For residential buildings, we build upon the work of Marinova et al. (2019, this issue), who used a building material database to come up with scenarios for materials in the residential building stock. This paper adds two things. First, we introduce a new regression-based model for service building floor space, recognizing 4 different types of service-related buildings. Secondly, we use a dynamic stock model, based on lifetime distributions found in literature, to calculate the construction (inflow) and demolition (outflow) of building floor space for both residential and service-related purposes. We combine this with data from the building material database to come up with scenarios for the annual demand for construction materials worldwide as well as an estimation of the availability of waste materials after building demolition towards 2050. The model can thus be used to assess the potential for closing the material cycles in the construction sector, while distinguishing urban and rural areas explicitly. The results show that demand for construction materials will continue to increase in most regions, even in developed countries. Global demand for steel and cement for the building sector is estimated to be 769 Mt/yr and 11.9 Gt/yr respectively, by the end of the modelling period. This represents a respective growth of 31% and 14% compared to today. Drivers behind this are an expected growth of global residential building stock of about 50%, and a growth of about 150% in the building stock for services. Our model projects that by 2050, only 55% of construction-related demand for copper, wood and steel could potentially be covered by recycled building materials. For other materials the availability of scrap may be higher, reaching up to 71% of new demand in the case of aluminium. This means that in most regions urban mining cannot cover the growing demand for construction materials. • A model on global building stock and construction materials demand was developed. • Building stock includes four types of residential and four types of service sector buildings. • A dynamic stock model was used to derive inflow and outflow of building materials. • Results highlight the growing demand for construction materials towards 2050. • Long lifespans of buildings pose a challenge for achieving a circular economy. [ABSTRACT FROM AUTHOR]

The composite system comprising mesoporous silica nanoparticle KIT-6 with I3ad symmetry and polyelectrolyte complex (κ-carrageenan/chitosan/κ-carrageenan) was utilized as a promising carrier for the effective delivery of quercetin. KIT-6 silica nanoparticles with sizes around 45 nm were synthesized and modified with amino groups by post-synthesis method. Quercetin was successfully loaded into the amino-modified KIT-6 silica by incipient wetness impregnation or by solid state method. The quercetin-loaded KIT-6NH 2 particles were coated by a two-layer polymer complex of oppositely charged polysaccharides. All the materials were characterized by XRD, N 2 physisorption, thermal gravimetric analysis, AFM and ATR FT-IR spectroscopy. In-vitro release profile of quercetin loaded formulations was studied in a phosphate buffer with pH = 6.8. Polymer coated KIT-6NH 2 formulations prepared by both methods showed slower quercetin release compared to that from the uncoated ones. ATR-FT-IR spectroscopic data suggested weak interaction of quercetin with the NH 2 -KIT-6. Density functional modeling revealed some aspects of quercetin bonding to the functionalized carrier at molecular level. The binding of quercetin to the protonated amino-functionalized silica carrier via the carbonyl group of the drug is more than twice weaker than the binding to the neutral carrier, which allows to be released easily as could be observed experimentally. The cytotoxicity potential of the mesoporous carrier was studied in three human cell lines (HEK-293, HL-60 and HUT-78). A comparative evaluation of the cytotoxic effect of quercetin loaded system vs. free drug was investigated in HUT-78 cell line. [ABSTRACT FROM AUTHOR]

SBA-16 and MCM-41 silica materials were synthesized and modified by post-synthesis method with different amounts of Zn (2 and 4 wt.%). Quercetin, a flavonol compound, was loaded by incipient wetness impregnation method on the pure silica and Zn-modified mesoporous MCM-41 and SBA-16 supports. The parent and drug loaded formulations were characterized by powder XRD, N 2 physisorption, thermal analysis, TEM, UV Vis and FT-IR spectroscopies. The formation of Zn:quercetin complex was studied by FT-IR spectroscopy and quantum-chemical calculations. Loading of quercetin on mesoporous carriers made the sustained delivery of the bioactive compound possible in a buffer with pH = 5.5, typical of dermal formulations. The results from the release experiments are in good accordance with the interaction energy between the bioactive molecule and non-modified and Zn-modified mesoporous materials, predicted by the quantum-chemical calculations. For the first time the formation of the most stable Zn quercetin complexes loaded on the mesoporous silica materials were determined. The obtained mesoporous delivery systems with Zn-quercetin complex are promising as dermal formulations. [ABSTRACT FROM AUTHOR]