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Air-conditioning accounts for a vast amount of electricity consumption in Hong Kong, and household decarbonization of cooling is considered a vital means of reducing electricity use. However, little information is available on the determinants of household decarbonizing cooling behaviour, and emotional factors are often ignored in the pro-environmental behaviour literature. Thus, this study attempts to address this gap by applying an emotional extension of the theory of planned behaviour (TPB). A total of 295 valid responses were obtained using a questionnaire survey and tested via structural equation modeling (SEM). The incorporation of additional variables improves the explanatory power of the household decarbonizing cooling behaviour model, and the results reveal that subjective norms is the most influential factor, followed by affective connection to nature and negative anticipated emotions. Meanwhile, attitude towards the behaviour and perceived behavioural control are found to have a nonsignificant effect on behavioural intention. These findings not only highlight the importance of emotions in predicting electricity-saving behaviour, but also provide useful insights to formulate effective approaches for motivating citizens to engage in decarbonizing cooling behaviour at home.

The development of an ultra-efficient heterogeneous Fenton catalyst that has practical application and can be easily separated is of great importance. In this study, a novel nanocomposite, Fe0/CeO2, was successfully synthesised and applied for Fenton oxidation of tetracycline. The results show that Fe0/CeO2 significantly enhanced the removal of pollutants, which suggests a synergistic effect between nanoscale zero-valent iron and CeO2. Furthermore, the composite catalyst exhibited ideal reusability and wide pH adaptation. A radical identification experiment revealed that surface-bounded OH ( OHads) played a critical role in Fenton reaction, and compared with bare nanoscale zero-valent iron, Fe0/CeO2 remarkably promoted the generation of OH in the Fenton system, mostly because CeO2 not only increased the adsorption properties of the catalyst, it also accelerated electron transfer to promote the decomposition of H2O2 due to the abundance of surface oxygen vacancies. A reasonable degradation pathway was also proposed for tetracycline on the basis of the detected intermediates. Our findings help to understand the mechanism of tetracycline degradation by heterogeneous Fenton-like, and also provide an efficient system for organic wastewater treatment.

Reducing the preparation cost of magnetic biochar is necessary for its large-scale application as an adsorbent. In this study, stainless steel pickling waste liquor and rice straw were successfully applied to synthesize of magnetic biochar (SPWL-MBC). Several iron oxides adhered on the biochar matrix, mainly Fe3O4, Fe2O3 and FeO. SPWL-MBC exhibited superparamagnetism, and its specific surface area was 274.29 m2/g. The material was able to adsorb a model contaminant, crystal violet (CV), with a maximum adsorption capacity of approximately 111.48 mg/g. Adsorption mechanism analysis showed that iron oxides, π-π interaction, hydrogen bonding and electrostatic interaction were responsible for the adsorption of CV. The CV adsorption efficiency of SPWL-MBC remained 71.91% after three adsorption-regeneration cycles. These outcomes illustrate that the magnetic biochar prepared from stainless steel pickling waste liquor can effectively remove CV from wastewater.

Exploiting the full potential of copper-based nanoparticles in the activation of peroxymonopersulfate (PMS) is a great challenge due to their insufficient dispersity and electronic properties. We report here a novel iron‑nitrogen co-doped carbon nanotube (FNC) modified with a Cu

This chapter introduces the edited collection of stories of green school movements around the world and the impacts they have had on the development of environmental education and education for sustainable development in their respective countries.

The Hong Kong Green School Award (HKGSA) is a school award scheme hosted by the Environmental Campaign Committee (ECC) to encourage schools to promote environmental awareness and for students to develop an environmentally-friendly lifestyle. Since its inception in 2000, the HKGSA has undergone several phases of development. Between 2000 to 2008 it took the form of a competition with 3 winning schools and 10 merit schools After an initial review in 2005, it was decided to change the 8th HKGSA from a competition format to a benchmarking process. The successfully accredited schools were given the title of Green School once they fulfilled certain requirements. Another major reform took place in the 12th HKGSA in 2013 to allow flexibility for schools to satisfy the requirements in phases by completing the accreditation to attain the gold award over a period of 3 years, the introduction of facilitators to act as mentors and the enforcing of a maximum validity period for the accreditation. This structure mirrored the sustainable schools program in Victoria, Australia. HKGSA has become a well-received accreditation scheme which can also act as a driving force to promote education for sustainable development in the school sector which in 2020 will be subsumed under the Hong Kong Awards for Environmental Excellence (HKAEE). This chapter describes the development of this initiative in Hong Kong, its framework, implementation, impact and future.

Nanoscale zero-valent iron nanoparticles (nZVI) have been used for groundwater remediation and wastewater treatment due to their high reactivity, high adsorption capacity and nontoxicity. However, side reactions generally occur in tandem with the target contaminants removal process, resulting in poor electron selectivity (ES) of nZVI, and subsequently restricting its commercial application. Major efforts to increase ES of nZVI have been made in recent years. This review's objective is to provide a progress report on the significant developments in nZVI's ES during the past decade. Firstly, the definition of ES and its quantification approaches were documented, and the intrinsic (i.e. particle size, crystallinity, and surface area) and extrinsic factors (i.e. solutions pH, target contaminant concentration, and presence of co-contaminants) affecting the ES of nZVI were reported. The latest techniques for increasing ES were summarized in detail, with reference made to sulfidation, magnetization, carbon loading and other features. Then the mechanisms of those strategies for ES enhancement were described. Finally, some constructive suggestions on future research directions concerning nZVI's ES in the future were proposed.

A type of biochar-supported iron phosphate nanoparticle stabilised by a sodium carboxymethyl cellulose (CMC@BC@ Fe3(PO4)2) composite was synthesised to remediate cadmium (Cd)-polluted soil. The surface morphology and functional groups of the composite were characterised by scanning electron microscopy and Fourier transform infrared spectrometry, respectively. Batch experiments showed that the composite (soil-to-solution ratio 1 g:10 mL) could effectively immobilise Cd in soil. The immobilisation efficiency of Cd was 81.3% after 28 days of remediation, and physiological-based extraction test bioaccessibility was reduced by 80.0%. The results of sequential extraction procedures indicated that the transformation from more easily extractable Cd to the least available form was responsible for the decrease in Cd bioavailability in soils. Plant growth experiments proved that the composite could inhibit Cd uptake to the belowground and aboveground parts of cabbage mustard by 44.8% and 70.2%, respectively, thus promoting cabbage mustard growth and development after remediation.

The magnetic Fe0@Fe3O4 nanocomposite was prepared and used to achieve the reductive/subsequent oxidative ring-opening of decabromodiphenyl ether (BDE209) in this work. The characterization results indicated that the structure of the composite consisted of small nanoscale zero-valent iron (nZVI) particles surrounding the surface of Fe3O4 nanoparticle (NP). A 100% removal efficiency and 80% degradation efficiency of BDE209 was reached by the composite accompanied with ultrasound(called NP/US system) for 36 h, which is higher than that obtained with conventional nZVI particles. Furthermore, the enhanced debromination and ring-opening of BDE209 was realized by a Fenton-like degradation process lasting for 12 h after the addition of H2O2 to the NP/US reaction at 36 h. Based on the degradation products identified, a two-stage reduction/oxidation degradation mechanism was proposed. During the first stage, which was reductive debromination, the major reductive activity of nZVI was efficiently enhanced in the presence of nano Fe3O4, which served as a catalyst to improve the stability of the nZVI nanoparticles and accelerate electron transfer, enhancing the degradation efficiency of BDE209. During the second stage, the oxidative ring-opening, the debromination products of BDE209 were proved to be attacked by abundant hydroxyl radicals generated both in the solution and on the surface of the Fe0@Fe3O4 nanoparticles. Thus, this work provides an efficient method to achieve the complete ring-opening of PBDEs using iron-based nanomaterials.

The difficulty of separating the powdered biochar from the environmental medium may lead to secondary pollution and hinder the large-scale application of biochar as an adsorbent. An effective strategy to solve this bottleneck is to introduce transition metals and their oxides into the biochar matrix, creating easily separable magnetic biochar. Magnetic biochar is also effective for the removal of pollutants from aqueous solution. This review comprises a systematic analysis of 109 papers published in recent years (From 2011 to June 2019), and summarises the synthetic methods and raw materials required for magnetic biochar preparation. The basic physicochemical properties of magnetic biochar are expounded, together with findings from relevant studies, and the application of magnetic biochar as an adsorbent or catalyst in environmental remediation are summarised. Other applications of magnetic biochar are also discussed. Finally, some constructive suggestions are given for the future direction of magnetic biochar research.

This study examined the relationship between surface oxygen vacancies (OVs) and ceria-based heterogeneous Fenton catalytic activity. Compared with pure iron oxide and ceria, iron-doped ceria with abundant OVs (FeCeOx) exhibits higher rhodamine B (RhB) degradation efficiency (98%) and has a wider applicable pH range (3.0–9.0). The surface hydroxyl radicals are proved to be the predominant reactive species in the oxidation of RhB. Annealing the FeCeOx in an oxygen atmosphere appears to eliminate the OVs, significantly inhibiting the decomposition of H2O2 and the degradation of target pollutants. As multifunctional active sites, OVs are energetically more favorable for the adsorption of reactants than other sites, due to their high electron density. They not only accelerate the Fe(III)/Fe(II) cycle, they also immediately activate H2O2, dissolved oxygen or even water molecules to produce oxidative species, which accounts for the ideal degradation of RhB in the heterogeneous Fenton system. This study clarifies the mechanism of the ceria-based heterogeneous Fenton and provides a better understanding of the surface design of heterogeneous Fenton catalysts.

Exploiting the full potential of copper-based nanoparticles in the activation of peroxymonopersulfate (PMS) is a great challenge due to their insufficient dispersity and electronic properties. We report here a novel iron‑nitrogen co-doped carbon nanotube (FNC) modified with a Cu2O nanocomposite (Cu2O/FNC) that exhibits ultrahigh catalytic performance in the activation of PMS to degrade fluconazole (~95%). Catalytic performance evaluation illustrated that Cu2O/FNC also has wide pH applicability (3.0-11.0), long-term stability and excellent adaptability. In addition, luminescent bacteria toxicity tests confirm that Cu2O/FNC/PMS significantly reduced the acute biotoxicity of various recalcitrant pollutants (reduced by 45-83%). By identifying the reactive oxygen species (ROS) and catalytic performance for various pollutants, we propose that pollutants that interact weekly with activators are mostly destroyed by sulfate radicals and hydroxyl radicals, whilst both radical and non-radical routes were involved in the degradation of pollutants that were easily adsorbed. By modifying Cu2O with FNC, several crucial properties such as the specific surface area, surface defects, active sites and the charge transfer rate were significantly improved, leading to excellent catalytic performance for pollutant removal. Finally, a reasonable reaction mechanism is advanced for the fluconazole degradation pathway. This study not only develops a novel PMS oxidation system for fluconazole degradation, but also provides a new strategy to improve the reactivity and applicability of PMS activators by combining radical and non-radical activation pathways.

Common plasticizers and their alternatives are environmentally ubiquitous and have become a global problem. In this study, common plasticizers (phthalates and metabolites) and new alternatives [bisphenol analogs, t-butylphenyl diphenyl phosphate (BPDP), and bisphenol A bis(diphenyl phosphate) (BDP)] were quantified in urine and hair samples from children in Hong Kong, drinking water (tap water/bottled water) samples, and airborne particle samples from 17 kindergartens in Hong Kong. The results suggested that locally, children were exposed to various plasticizers and their alternatives. High concentrations of BPDP and BDP were present in urine, hair, tap water, bottled water, and air particulate samples. The geometric mean (GM) concentrations of phthalate metabolites in urine samples (126-2140 ng/L, detection frequencies 81%) were lower than those detected in Japanese and German children in previous studies. However, a comparison of the estimated daily intake values for phthalates in tap water [median: 10.7-115 ng/kg body weight bw/day] and air particles (median: 1.23-7.39 ng/kg bw/day) with the corresponding reference doses indicated no risk. Bisphenol analogs were detected in 15-64% of urine samples at GM concentrations of 5.26-98.1 ng/L, in 7-74% of hair samples at GM concentrations of 57.5-2390 pg/g, in 59-100% of kindergarten air samples at GM concentrations of 43.1-222 pg/m

Fruit peels were discarded as inevitable wastes in the production of fruit juice which wasted our resources and caused pollution problems. In this paper, iron nanoparticles were synthesized using Citrus maxima peel extracts to reduce Fe(III) in aqueous solution. The nanoparticles were characterized by TEM, EDS, XPS, FTIR, DLS and Zeta potential methods. Based on the characterization results, irregular iron nanoparticles with diameters of 10–100 nm were synthesized successfully. Moreover, the nanoparticles were mainly composed of Fe0 nanoparticles which were coated with various biomolecules from the extracts as capping or stabilizing agents.

Some problems exist in the current remediation of polybrominated diphenyl ethers (PBDEs) from aqueous solution by using iron-based nanoparticles. Our efforts have contributed to the synthesis of biochar-supported Ni/Fe bimetallic nanoparticle composites (BC@Ni/Fe). Under the optimum operating parameters of BC@Ni/Fe, the morphologic analysis revealed that biochar effectively solved the agglomeration of Ni/Fe nanoparticles and the removal efficiency of BDE209 obtained by BC@Ni/Fe (91.29%) was seven times higher than the sum of biochar (2.55%) and Ni/Fe (11.22%) in 10 min. The degradation products of BDE209 in the solution and absorbed on the BC@Ni/Fe were analyzed with gas chromatography-mass spectroscopy, which indicated that the degradation of BDE209 was mainly a process of stepwise debromination. Meanwhile, compared with Ni/Fe nanoparticles, the adsorption ability of the by-products of BDE209 by BC@Ni/Fe was greater, to a certain extent, which reduced the additional environmental burden. In addition, the concentration of nickle ion leaching from the Ni/Fe nanoparticles was 3.09 mg/L; conversely, the concentration of nickle leaching from BC@Ni/Fe was not detected. This excellent performance in our study indicates a possible means to enhance the reactivity and reduce the secondary risks of Ni/Fe nanoparticles.

In this study, soil culture experiments were conducted to explore the effects of biochar-supported Ni/Fe nanoparticles on the accumulation and translocation of polybrominated diphenyl ethers (PBDEs) in soil-plant system and its phytotoxicity to Brassica chinensis. Compared with those in BDE209 contaminated soils (S 1) and Ni/Fe nanoparticle-treated soil (S 3), the plant biomass, root, and shoot lengths in biochar-supported Ni/Fe nanoparticle-treated soil (S 4) were increased by 23 mg, 1.35 cm, and 2.08 cm and 27.2 mg, 1.75 cm, and 2.52 cm, respectively, suggesting that the phytotoxicity in S 4 treatment was significantly decreased. Moreover, in all treatments, the contents of BDE209, the total PBDEs, Ni, and Fe in sample plant tissues of S 4 were the lowest. In addition, the superoxide dismutase, peroxidase, and catalase activities in S 4 treatment were found to decrease by 33.8, 47.2, and 24.1%, respectively, compared to those in S 3. Results also showed that biochar addition not only reduced the uptake of PBDEs and heavy metals but also effectively improve soil fertility and reduce the leachability of Ni and Fe caused by Ni/Fe. Finally, the translocation factors (TFs) of PBDEs in four treatments followed the orders as S 1 > S 3 > S 4 > S 2, indicating that biochar has an inhibition effects on PBDE translocation in the plants. In summary, all of the results suggested that the phytotoxicity, translocation of PBDEs, and the negative effects caused by neat Ni/Fe nanoparticles in B. chinensis were decreased as a result of the effects of the biochar.

As a promising in situ remediation technology, nanoscale zero-valent iron (nZVI) can remove polybrominated diphenyl ethers such as decabromodiphenyl ether (BDE209) effectively, However its use is limited by its high production cost. Using steel pickling waste liquor as a raw material to prepare nanoscale zero-valent metal (nZVM) can overcome this deficiency. It has been shown that humic acid and metal ions have the greatest influence on remediation. The results showed that nZVM and nZVI both can effectively remove BDE209 with little difference in their removal efficiencies, and humic acid inhibited the removal efficiency, whereas metal ions promoted it. The promoting effects followed the order Ni2+>Cu2+>Co2+ and the cumulative effect of the two factors was a combination of the promoting and inhibitory individual effects. The major difference between nZVM and nZVI lies in their crystal form, as nZVI was found to be amorphous while that of nZVM was crystal. However, it was found that both nZVM and nZVI removed BDE209 with similar removal efficiencies. The effects and cumulative effects of humic acid and metal ions on nZVM and nZVI were very similar in terms of the efficiency of the BDE209 removal.

In this study, Fe 3 O 4 NPs (named as Fe 3 O 4 NPs-PO) were prepared by steel pickling waste liquor to reduce the cost of preparation, and were compared with those obtained by the common co-precipitation method (named as Fe 3 O 4 NPs-CP) which prepared from chemical reagent using BET, XRD, XPS, TEM and SEM techniques. The results indicated that Fe 3 O 4 NPs-PO nanoparticles mainly existed in the form of Fe 3 O 4 and appeared to be roughly spherical in shape with a size range of 20–50 nm. The heterogeneous Fenton-like catalytic capacity of Fe 3 O 4 NPs-PO in US + Fe 3 O 4 + H 2 O 2 system was comprehensively investigated. BPA could be degraded within a wide pH range of 7–10. The removal efficiencies of BPA were close to 100% and about 45% total organic carbon (TOC) in solution was eliminated at the optimized conditions. It was found that· OH radicals which mainly caused the degradation of BPA were promptly generated due to the catalysis of the Fe 3 O 4 NPs-PO. Furthermore, the comparative study of catalytic activity, stability and reusability between Fe 3 O 4 NPs-PO and Fe 3 O 4 NPs-CP showed that the two catalysts both remained good activity after several reaction cycles and no significant change in composition and structure was observed, the loss of catalyst was negligible, which demonstrated that Fe 3 O 4 NPs-PO were promising in ultrasonic Fenton-like process to treat refractory organics.

This study aimed to understand the environmental knowledge (EK) of the residents of Hong Kong. A territory-wide survey was administered to investigate the subjective and objective EK of the respondents as well as their means of receiving information about the environment. The results indicated that Hong Kong’s residents have a comparatively low level of EK, with a mean environmental knowledge score of 3.35 out of 8. The youngster (15–24 years old), students, and employed individuals reported more extensive EK than the older and unemployed respondents, thus suggesting that the younger generation and employed individuals have increased opportunities to receive EK through various channels. A weak positive correlation was identified between subjective and objective EK, thus implying that the residents of Hong Kong could not accurately evaluate their own level of EK. The results indicate that traditional media plays a significant role in disseminating EK. Digital media, such as websites and digital social netw...

Benzophenones (BPs) and other ultra violet (UV) filters (UV-filters) are widely used in sunblock and other personal care products, raising concerns about their adverse health risks to human, especially for children. In the present study, BP-type UV-filters and other four widely used UV-filters were evaluated in the child urinary samples (4–6 years, n = 53), tap water and commercial distilled water in Hong Kong. The results suggested that the target chemicals are ubiquitous in the subject. BP1, BP2, BP3 and BP4 in children urine samples contributed closely to the overall children exposure of UV filters, with detection rates above 58% and geometric means ranging from 44.2 to 76.7 ng/mL. As a contrast, BP3 was the major substance found in the tap water and distilled bottle water, with detection rates of 100% and geometric means of 9.64 and 14.5 ng/L, respectively. There were some significant relationships between urinary UV filters and personal characteristics (BMI values, sex, income level, hand washing frequency, and body location usage), but the health risks associated with UV-filters in Hong Kong children might not be concerning. Only two children applied sun creams in this research, indicating that there were other sources to exposure these chemicals. Keywords: UV-filters, Urine, Children, Drinking water

We compared the degradation behavior of metronidazole (MNZ) under advanced oxidation processes with the aim of enhancing the mineralization of MNZ. Among the advanced processes used, that is, Ce/SnO 2 –Sb/Ti electrochemical/anode oxidation (EC/AO), the Fenton and the electro-Fenton (EF) processes, the EF process was the most effective. Different input variables, including catalyst concentration, [H 2 O 2 ]/[Fe 2+ ] molar ratio, and pH level were evaluated to find the optimum condition for mineralization by EF treatment. The total organic carbon was optimally diminished by up to 37% by applying a Fe 2+ concentration of 2.0 mM, a [H 2 O 2 ]/[Fe 2+ ] molar ratio of 10:1, and a pH of 2.0. The change in biodegradation was investigated on the basis of the BOD 5 /COD cr ratio. The ratio of BOD 5 /COD cr of raw MNZ aqueous (0.227) was increased to 0.252 and 0.345 by the EC and EF systems, respectively. The general toxicity resulting from the different treatments for MNZ aqueous solution was assessed by the Photobacterium bioassay. The toxicity of the EF-treated solution decreased 63%, falling to an effectively non-toxic level, indicating that the EF process can decontaminate and mineralize MNZ into a non-toxic product. According to the BOD 5 /COD cr ratio, the EF process is a sufficiently powerful pretreatment technology that can increase the biodegradability and decrease the toxicity of wastewater containing MNZ, providing a favorable condition for subsequent biochemical treatment.

Ni/Fe bimetallic nanoparticles were synthesized using biochar as a support (BC@Ni/Fe) and their effectiveness in removing BDE209 from soil was investigated. BET, SEM, TEM, XPS and FTIR were used to characterize the catalyst, and the efficiencies of biochar, Ni/Fe nanoparticles and BC@Ni/Fe for removing BDE209 from soil were compared. The results showed that Ni/Fe bimetallic nanoparticles highly dispersed in the biochar, reducing its agglomeration. Thus, the reaction activity of BC@Ni/Fe was increased. The removal efficiency of BDE209 by BC@Ni/Fe was 30.2% and 69% higher than that by neat Ni/Fe and biochar, respectively. Meanwhile, an enhanced degradation efficiency of PBDEs in soil was realized by monitoring the formation of Br⿿ ions with time in the system. In addition, the degradation products identified by GC⿿MS showed that the reductive degradation of BDE209 proceeded through stepwise or multistage debromination, for which the degradation pathways and removal mechanisms were speculated. Furthermore, BC@Ni/Fe reduced the bioavailability of metals in soil and adsorbed the degradation products of BDE209, representing an improvement over neat Ni/Fe nanoparticles for the remediation of PBDEs-contaminated soil.

Nano zero-valent iron (nZVI) and its modified nanomaterials are widely used in the degradation of some halogenated organic pollutants. In this study, we explored the effects of different proportions of tetrahydrofuran (THF) (50, 60, 70, 80, 90, and 100 %) on the degradation of decabromodiphenyl ether (BDE209) by Ni/Fe and nZVI nanoparticles with reference to the degradation kinetics, products, and pathway. The results illustrated that the effects of solvent on the degradation of BDE209 were similar when the two kinds of nanomaterials were used, although the Ni/Fe bimetallic nanoparticles exhibited a better catalytic activity compared with the pure nZVI during the degradation of BDE209. The apparent reaction rate constant (k obs) increased with the proportion of the water in the system, enhancing the degradation of BDE209. In terms of degradation products, a high proportion of THF led to an accumulation of higher-brominated BDEs, inhibiting the further debromination of BDE209. The inhibitory effect of the solvent (THF) can be explained that water played a role of hydrogen donor during the reductive degradation of BDE209 in the THF/water system. However, the proportion of THF in the degradation system posed no effect on the BDE209 debromination pathway and debromination location. The difficulty of para-debromination was observed in all of the solvent systems.

The potential for nanoscale phosphate amendments to remediate heavy metal contamination has been widely investigated, but the strong tendency of nanoparticles to form aggregates limits the application of this technique in soil. This study synthesized a composite of biochar-supported iron phosphate nanoparticle (BC@Fe3(PO4)2) stabilized by a sodium carboxymethyl cellulose to improve the stability and mobility of the amendment in soil. The sedimentation test and column test demonstrated that BC@Fe3(PO4)2 exhibited better stability and mobility than iron phosphate nanoparticles. After 28 days of simulated in situ remediation, the immobilization efficiency of Cd was 60.2 %, and the physiological-based extraction test bioaccessibility was reduced by 53.9 %. The results of sequential extraction procedures indicated that the transformation from exchangeable (EX) Cd to organic matter (OM) and residue (RS) was responsible for the decrease in Cd leachability in soil. Accordingly, the pot test indicated that Cd uptake by cabbage mustard was suppressed by 86.8 %. Compared to tests using iron phosphate nanoparticles, the addition of BC@Fe3(PO4)2 to soil could reduce the Fe uptake of cabbage mustard. Overall, this study revealed that BC@Fe3(PO4)2 could provide effective in situ remediation of Cd in soil.

Health literacy is an increasingly important issue amongst scholars of health studies and medical practitioners. This essay seeks to understand how health knowledge is co-constructed by different agencies and the role of health communication in this process can contribute to everyday-ing health literacy. In addition, this essay attempts to understand how health communication becomes an everyday practice in identifying disease-specific needs.

Metasequoia glyptostroboides is a famous living fossil. It is one of the most successfully recovered endangered species based on the number of extant individuals and the distribution range. However, previous studies have revealed low genetic variation in restored populations. This paper evaluates the natural regeneration ability of the natural and restored populations. The seed masses and germination rates of restored populations were found to be significantly lower than those in natural populations, indicating decreased regeneration ability in the restored populations. The decreased germination rate in the restored populations may be due to inbreeding depression. Very low seed germination rates show that it is very difficult for the restored populations to regenerate naturally, consistent with field surveys. This is the first report on a species that has successfully produced hundreds of millions of individuals but has difficulty in regenerating naturally. Our study highlights the role of population viability analysis in delisting or downlisting species under protection.

In the last few decades, the Asia Pacific region has faced unprecedented social, economic, political and environmental challenges. These in turn have prompted the necessity for partnerships on order to realise sustainable development in the region.

UNLABELLED PREMISE OF THE STUDY Polymorphic microsatellite primers were developed in the seagrass Zostera japonica to investigate genetic variation and to identify clonal structure. • METHODS AND RESULTS Thirteen polymorphic loci and 23 monomorphic loci were developed in Z. japonica. Two to 13 alleles per locus were observed at the polymorphic loci across 57 individuals of two Z. japonica populations. The observed and expected heterozygosities within populations ranged from 0.0000 to 1.0000 and from 0.0000 to 0.8542, respectively. • CONCLUSIONS Our study showed high-level polymorphism at the polymorphic loci in Z. japonica. These primers would be a powerful tool to study genetic variation, clonal structure, and mating systems.

E-waste sites are one of the main sources of the pollutant decabromodiphenyl ether (BDE209); contaminated farmland and water bodies urgently need to be remediated. As a potential in situ remediation technology, nano zero-valent iron (nZVI) technology effectively removes PBDEs. However, the humic acid (HA) and heavy metals in the contaminated sites affect the remediation effects. In this study, we explored the influence of HA and transition metals on the removal of PBDEs by nZVI. The specific surface area and average size of the nZVI particles we prepared were 35 m2/g and 50–80 nm, respectively. The results showed that HA inhibited the removal of PBDEs; as the concentration of HA increased, its inhibitory effect intensified and the k obs decreased. However, the three metal ions (Cu2+, Co2+, and Ni2+) enhanced the removal of PBDEs. The enhancement effect was followed the order Ni2+ > Cu2+ > Co2+. As the concentration of metal ions increased, the promotion effect improved. The synergistic effect of HA and the metal ions was manifested in the combination of the inhibitory effect and the enhancement effect. The values of the first-order kinetic constants (k obs) under the combined effect were between the values of the rate constants under the individual components. The inhibitory mechanism was the chemisorption of HA, i.e., the benzene carboxylic and phenolic hydroxyl groups in HA occupied the surfactant reactive sites of nZVI, thus inhibiting the removal of BDE209. The promotion mechanism of Cu2+, Co2+, and Ni2+ can be explained by their reduction to zero valence on the nZVI surface; furthermore, Ni2+ strongly affects the debromination and dehydrogenation of BDE209, leading to a stronger promotability than Cu2+or Co2+.

Nano zero-valent iron has been considered a promising material for in situ remediation, but its strong tendency to form aggregates makes it difficult to transport in porous media. Thus, stabilization techniques are required to overcome this limitation. In this study, we use polyvinylpyrrolidone (PVP) to synthesise to stabilise iron nanoparticles. The effects of various factors such as nZVI influent concentrations, flow velocity, Ca2+, Mg2+ and humic acid on the transport behaviour of the PVP-nZVI particles were considered. A sedimentation test indicated that PVP-nZVI particles with diameters ranging from 50 to 80 nm were more stable than Bare-nZVI particles. Column experiments demonstrated that PVP-nZVI also exhibited better mobility in silica sand than Bare-nZVI. Due to either the straining or blocking effect, the effluent relative concentration (C/C0) plateau increased with increasing particle concentration. Increasing the flow velocity increased the C/C0, resulting in the reduction of overall single-collector contact efficiency (η0). Humic acid (HA) enhanced the mobility of PVP-nZVI, and the sedimentation test in the presence of HA suggested that decreased attachment of PVP-nZVI to the silica sand surface rather than decreased aggregation was the primary mechanism of this enhanced mobility.

In this study, Fe3O4 NPs (named as Fe3O4 NPs-PO) were prepared by steel pickling waste liquor to reduce the cost of preparation, and were compared with those obtained by the common co-precipitation method (named as Fe3O4 NPs-CP) which prepared from chemical reagent using BET, XRD, XPS, TEM and SEM techniques. The results indicated that Fe3O4 NPs-PO nanoparticles mainly existed in the form of Fe3O4 and appeared to be roughly spherical in shape with a size range of 20-50 nm. The heterogeneous Fenton-like catalytic capacity of Fe3O4 NPs-PO in US+Fe3O4+H2O2 system was comprehensively investigated. BPA could be degraded within a wide pH range of 7-10. The removal efficiencies of BPA were close to 100% and about 45% total organic carbon (TOC) in solution was eliminated at the optimized conditions. It was found that ·OH radicals which mainly caused the degradation of BPA were promptly generated due to the catalysis of the Fe3O4 NPs-PO. Furthermore, the comparative study of catalytic activity, stability and reusability between Fe3O4 NPs-PO and Fe3O4 NPs-CP showed that the two catalysts both remained good activity after several reaction cycles and no significant change in composition and structure was observed, the loss of catalyst was negligible, which demonstrated that Fe3O4 NPs-PO were promising in ultrasonic Fenton-like process to treat refractory organics.

The toxic effect of Cr(VI)-contaminated soil remediated by sodium carboxymethyl cellulose stabilized nanoscale zero-valent iron (CMC-stabilized nZVI) was assessed through in vitro toxicity and phytotoxicity tests. In vitro tests showed that 0.09 g L−1 of Fe0 nanoparticles (soil-to-solution ratio was 1 g:5 mL) significantly reduced the toxicity characteristic leaching procedure (TCLP) leachability and physiological based extraction test (PBET) bioaccessibility of Cr by 82% and 58%, respectively. Sequential extraction procedures (SEP) revealed that exchangeable (EX) Cr was completely converted to Fe–Mn oxides (OX) and organic matter (OM). Accordingly, phytotoxicity tests indicated that after 72-h remediation, Cr uptakes by edible rape and Chinese cabbage were suppressed by 61% and 36%, respectively. Moreover, no significant increase in Cr uptake was observed for either species after a 1-month static period for the amended soil. Regarding Fe absorption, germination and seedling growth, both plant species were significantly affected by CMC-nZVI-exposed soils. However, similar phytotoxicity tests conducted after 1 month showed an improvement in cultivation for both plants. Overall, this study demonstrated that CMC-nZVI could significantly enhance Cr immobilization, which reduced its leachability, bioavailability and bioaccumulation by plants. From a detoxification perspective, such remediation is technologically feasible and shows great potential in field applications.

Education for sustainable Development (ESD) in Hong Kong schools is administered by the Environmental Campaign Committee (ECC) through its core education programs, mainly the Hong Kong Green School Awards (HKGSA) and Student Environmental Protection Ambassador Scheme (SEPAS). This is supported partly by the SAR Government Education and Development Bureau (EDB) which seeks the permeation of ESD through the formal curriculum but is seriously hindered by the curriculum structure. Research recently conducted by the authors reveals that there are still questions to be answered regarding the readiness and willingness of schools to engage with ESD. In China, on the other hand, ESD is being promoted mainly through its Green School Program administered by the State Ministry of Education (MOE) and sponsored by the State Environmental Protection Agency (SEPA). This chapter provides an in-depth description and comparison of the history, development, and the theoretical framework of ESD for schools in Hong Kong and Mainland China.

Our previous reports showed that nano zero-valent iron (nZVI), steel pickle liquor for the synthesis of nZVI (S-nZVI), nZVI immobilised in mesoporous silica microspheres (SiO2@FeOOH@Fe) and nano Ni/Fe bimetallic particles (Ni/Fe) have been proved to show good property for elimination of polybrominated diphenyl ethers (PBDEs). However, it is necessary to compare their reactivity, reusability and stability when applied to in situ remediation. In this study, the performances of different iron-based nanoparticles were compared through reusability, sedimentation and iron dissolution experiments. The SiO2@FeOOH@Fe and Ni/Fe nanoparticles were shown to have higher reusability and stability, as they could be reused more than seven times, and that the SiO2@FeOOH@Fe can effectively avoid leaching iron ions into the solution and causing secondary pollution in the reaction. This study may serve as a reference for PBDE remediation in the future.

Climate change is generating economic and environmental threats with the pressures set to increase in the coming years. However, these threats also provide opportunities for those cities and regions that seek to address climate change by pursuing lower emission technologies. Where environmental concerns were once associated with problems of high costs and inefficiency, responding to the climate crisis is now rapidly becoming a high-growth industry where profits and returns are increasingly attractive. Research by the Environmental Protection Department identified electricity generation, property development, construction, transport and hospitality as ‘carbon-vulnerable’ industries in Hong Kong, China. This chapter has identified the potential workforce skills needed for Hong Kong, China, in these industries to create new and alternative economic opportunities through a shift to low-carbon technologies, aiming at identifying the changes in vocational training that are required to respond to the skills needs of industry and businesses resulting from climate change.

To study the possibilities for improvement of the ornamental character and production of secondary metabolites by using Wedelia trilobata hairy roots, we investigated the induction of W. trilobata L. hairy roots and its consumption changes of carbon resource, nitrogen resource, phosphate and calcium in the medium during liquid culture. The results showed that hairy roots could be incited from the cut edges of leaf explants 7 days after inoculation with Agrobacterium rhizogenes ATCC15834 and could have an autonomous growth on the medium without phytohormones. The PCR amplification showed that rol genes of Ri plasmid of A. rhizogenes was integrated and expressed into the genome of transformed hairy roots. The hairy root line grew very slowly in 0-7 days, very fast from 7 to 21 days. During the liquid culture of hairy roots, sucrose, NO3(-)-N, PO4(3-) and Ca2+ in the medium could be gradually absorbed and utilized with time. The content of NO3(-)-N in the medium was 5.8% of the initial amount at day 7, while sucrose content was about 50% of the initial amount. At day 35, the NO3(-)-N and sucrose content in the medium was 1.82% and 3.39% of the initial amount, respectively. In combination with Ca2+ consumption, PO4(3-) of the medium was rapidly absorbed and utilized. At day 7, the content of PO4(3-) in the spent medium was only 1.76% of the initial amount; but even at day 35, the content of Ca2+ in the spent medium was still 61.3% of the initial amount. The results presented here had provided the possibilities on improvement the ornamental character and how to prepare optimum medium for large scale cultivation and production of secondary metabolites from W. trilobata L. hairy roots.

To study if Solanum nigrum hairy roots can be used for phytoremediation of Cd contamination, we investigated the effects of cadmium (Cd) alone, and in combination with different concentrations of CaCl2, on growth, activities of superoxide dismutase (SOD) and peroxidase (POD) and Cd absorption by hairy roots of S. nigrum L. var pauciflorum. The results showed that Cd concentrations of lower than 50 micromol/L enhanced the growth of hairy roots, while higher than 100 micromol/L inhibited growth and decreased the number of branched roots, also causing the root tips to become brown and shorter in length. In comparison with a control, the soluble protein content, the activities of SOD and POD in hairy roots cultures showed a trend of first increased and then gradually decreased, while the malondialdehyde (MDA) content significantly increased, when increasing the Cd concentrations. Cd concentration of 100 micromol/L or 300 micromol/L in combination with 10-30 mmol/L CaCl2 resulted in a decreased content of soluble protein and MDA in the hairy roots, but an enhanced SOD activity. The increased POD activities were observed when cultured in 100 micromol/L Cd and 10-30 mmol/L CaCl2 but decreased when cultured in 300 micromol/L Cd and 10-30 mmol/L CaCl2. Atomic Absorption Spectrometry determination showed that the Cd absorbed and adsorbed by the hairy roots increased along with the increase of Cd concentration. The exogenous addition of 10-30 mmol/L CaCl2 could reduce the toxicity of Cd. This was achieved on one hand by reducing the absorption of Cd, on the other hand by decreasing the lipid peroxidation through regulating the activities of antioxidant enzymes SOD and POD in the hairy roots.