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Color centers in hexagonal boron nitride (hBN) have been emerging as a multifunctional platform for various optical applications including quantum information processing, quantum computing and imaging. Simultaneously, due to its biocompatibility and biodegradability hBN is a promising material for biomedical applications. In this work, we demonstrate single-photon emission from hBN color centers embedded inside live cells and their application to cellular barcoding. The generation and internalization of multiple color centers into cells was performed via simple and scalable procedure while keeping the cells unharmed. The emission from live cells was observed as multiple diffraction-limited spots, which exhibited excellent single-photon characteristics with high single-photon purity of 0.1 and superb mission stability without photobleaching or spectral shifts over several hours. Due to different emission wavelengths and peak widths of the color centers, they were employed as barcodes. Each color center can exist in one out of 470 possible distinguishable states and a combination of a few color centers per cell can be used to uniquely tag virtually an unlimited number of cells. This barcoding technique is superior to others in almost all respects, including ease of production by a single-step procedure, biocompatibility and biodegradability, emission stability, no photobleaching, small size and a huge number of unique barcodes. This work provides a basis for the use of hBN color centers for robust barcoding of cells and due to the single photon emission, presented concepts could in future be extended to quantum-limited sensing and super-resolution imaging.

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Poplar (Populus spp.) are among the fastest growing timber species and have been widely planted for use in plywood, composites, pallets, furniture components and paper production. However, the low density of the wood limits many structural applications and the wood has little resistance to biodegradation. Thermal modification represents one approach to improving durability by changing the moisture behavior of the wood, but it can also have adverse effects on structural performance. Understanding the potential effects of thermal treatment on poplar properties can help define the most appropriate applications for these materials. Poplar timbers from Iran were subjected to 30 or 60 min of thermal treatment at temperatures ranging from 110 to 220 °C. Samples were then evaluated for mass loss during treatment, changes in flexural properties, e.g., modulus of elasticity (MOE) and modulus of rupture (MOR), the degree of polymerization, and water absorption characteristics. MOR of controls subjected to 100 °C were similar to those exposed to 160 °C, while MOE was more variable with a slight upward trend for samples exposed to a given heating regime for only 30 min. The increases in MOE may be related to changes in cellulose crystallinity. Mass losses increased with increasing temperature exposure while moisture absorption decreased as expected with longer thermal exposure. The degree of polymerization remained similar for samples exposed up to 170 °C and then increased at higher temperatures. The increases may reflect the complete destruction of shorter chain polymers, leaving only the heat-resistant longer chain polymers. The results suggest that poplar can be thermally modified within limited parameters to improve some performance attributes without adversely affecting its structural capacity.

Thermal drying is an effective sludge treatment method for dealing with large volumes of sludge. Microwave (MW) technology has been proposed as an effective and efficient technology for sludge drying. The physical-chemical properties of the sludge depend both on the origin of the sludge, as well as on the treatment process at which the sludge has been exposed. The physical-chemical properties of the sludge affect the performance and the subsequent valorisation and management of the sludge. This study evaluated the effect of certain physical-chemical properties of the sludge (moisture content, organic content, calorific value, porosity, hydrophobicity, and water-sludge molecular interaction, among others) on the MW sludge drying and energy performance. Four different types of sludge were evaluated collected from municipal wastewater treatment plants and septic tanks. The performance of the MW system was assessed by evaluating the sludge drying rates, exposure times, energy efficiencies and power input consumed by the MW system and linking the MW drying performance to the sludge physical-chemical properties. The results confirmed that MW drying substantially extends the constant drying period associated with unbound water evaporation, irrespective of the sludge sample evaluated. However, the duration and intensity were determined to depend on the dielectric properties of the sludge, particularly on the distribution of bound and free water. Sludge samples with a higher amount of free and loosely bound water absorbed and converted MW energy into heat more efficiently than sludge samples with a lower amount of free water. As a result, the sludge drying rates increased and the constant drying rate period prolonged; hence, leading to an increase in MW drying energy efficiency. The availability of free and loosely bound water molecules was favoured when hydrophobic compounds, e.g., oils and fats, were present in the sludge.

Depletion of global energy resources and global warming issues have been the theme topics of the world economic circle over the past decades. Looking at this scenario, it is essential to every sector including educational institution to play its role in engaging public and community at grass-roots level on these issues. Keeping the above factors in mind, a Knowledge Transfer Program (KTP) was carried out to transfer knowledge on curricula of energy and environment to a selected tertiary educational institution in Malaysia. The aim of this program was to link generated academic knowledge on energy and environment to targeted community or group as part of commitment to knowledge transfer. In order to achieve the aim, a partnership was formed between CETREE & GT and UniKL - MFI for two years with three main stages of program implementation comprising of: i) training on renewable energy and energy efficiency to graduate intern and technical support team; ii) selection of academic staff from the targeted community and; iii) a series of workshop. Two workshops were convened to develop and harmonize curricula of energy and environmental course and were followed by two more workshops to discuss, select and construct appropriate teaching aids and methods for the course. Design and development of the teaching aid were based on the model of an Energy Efficient Building by taking into account renewable energy and energy efficiency components such as solar energy, wind energy, biomass and thermal electric generator. With active involvement from university and community, in planning, executing, monitoring, control and closure, the program was successfully devised and managed. At the end of the program, a module of curricula for Energy and the Environment course and Energy Efficient Building teaching aid were developed. Through this program, contributions from both parties help to build committed societies to engage in important issues in relation to energy and environment towards

Climate change due to anthropogenic emissions is the largest environmental challenge of ourtime. Forest-based value chains play an important role in reducing the accumulation of CO2 in the atmosphere. Maximizing the use of wood to tackle climate change requires improved understanding of the service life of timber products. This information can best be obtained from field testing and while there is an abundance of field performance data from sites all over the world, most of the data are not available in a form that can be utilised for service life models. The IRG Durability Database aims to improve the usability of existing performance data and create added value for durability research and service life prediction. The present paper takes the first steps in comparing global field test performance data from the IRG Durability Database for non-durable reference species. Data were obtained from six species above ground and ground contact field tests from 36 sites around the world. For each dataset, decay rates and service life (where applicable) were calculated. Datasets were then grouped together based on test method and species. Decay rate was faster and more uniform in ground contact than above ground. Inground contact, beech decayed most rapidly, followed by Norway spruce and Scots pines apwood. All appeared to be suitable for use as reference species, however slow-grown spruce should be avoided. There were no statistically significant correlations between ground contact decay rate and the Scheffer Climate Index (SCI). In above ground tests, differences in decay ratewere largely related to differences in moisture dynamics. Species with the greatest absorption and retention of water decayed most rapidly. Test methods that absorbed and retained the most moisture (e.g. painted L-joints) resulted in more rapid decay. Above ground decay rate and SCI were significantly correlated in two data sets that had a wide range of SCI values. Correlations were not significant when

There are high amounts of post-consumed protected waste wood removed from service every year. The residual biocides, including copper, chromium and boron from CCB (Cu, Cr, B) in post-consumed wood that was protected with biocides may cause environmental problems during waste management, for example during land filling. Therefore, the aim of this study was to find out if Cu and Cr in the processed waste wood, previously treated with CCB, can be re-used as a wood preservative or in coatings made of liquefied wood. Liquefaction of CCB containing waste wood could be as well the first step in the elimination process of metals. So, the optimal conditions for liquefaction of CCB (Cu, Cr and B) containing black poplar (Populus nigra L.) wood were established and compared with liquefaction of uncontaminated black poplar wood. The reactants for liquefaction of black poplar wood sawdust were ethylene glycol (EG) and sulphuric acid. It was observed that in the last stages of the liquefaction process, the presence of Cu, Cr and B did not have any influence on liquefaction yield (LY), while their influence was observed in first stages of the solvolytic reaction. Investigations of fungicidal properties of uncontaminated and CCB containing liquefied wood showed higher antifungal efficacy of liquefied wood without Cu, Cr and B than of liquefied wood that contained CCB. In the tested concentration range, the presence of Cu even promoted the growth of selected wood decay fungi. One of the reasons for higher toxicity of liquefied black poplar sawdust without Cu, Cr and B, was its very low pH value.