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Facing the big data wave, this study applied artificial intelligence to cite knowledge and find a feasible process to play a crucial role in supplying innovative value in environmental education. Intelligence agents of artificial intelligence and natural language processing (NLP) are two key areas leading the trend in artificial intelligence, this research adopted NLP to analyze the research topics of environmental education research journals in the Web of Science (WoS) database during 2011–2020 and interpret the categories and characteristics of abstracts for environmental education papers. The corpus data were selected from abstracts and keywords of research journal papers, which were analyzed with text mining, cluster analysis, latent Dirichlet allocation (LDA), and co-word analysis methods. The decisions regarding the classification of feature words were determined and reviewed by domain experts, and the associated TF-IDF weights were calculated for the following cluster analysis, which involved a combination of hierarchical clustering and K-means analysis. The hierarchical clustering and LDA decided the number of required categories as seven, and the K-means cluster analysis classified the overall documents into seven categories. This study utilized co-word analysis to check the suitability of the K-means classification, analyzed the terms with high TF-IDF wights for distinct K-means groups, and examined the terms for different topics with the LDA technique. A comparison of the results demonstrated that most categories that were recognized with K-means and LDA methods were the same and shared similar words, however, two categories had slight differences. The involvement of field experts assisted with the consistency and correctness of the classified topics and documents.

Today's climate change is a major problem and challenge for the global environment and human civilization, and it can lead to dramatical floods over specific regions. As climate change intensifies, climate change adaptation strategies, such as flood insurance, energy taxes, and other risky financial strategies, have drawn worldwide attention and discussion. Risk control methods have been widely used to mitigate the impact of climate change on past flood losses, but past risk control strategies on climate change have not focused on the exploration of the relationship between environment, society, and humans. Based on the theoretical model of pro-environmental behavior, this study compares and analyzes four theoretical models and proposes a modified competitiveness model to effectively predict the pro-environmental behavior of college students with partial least squares (PLS) manner. Social norm could play a dominant role of mediator between risk perception, place attachment, and pro-environmental behavior. Although risk perception and local attachment are positively related to risk financial strategy, the promotion of social norms will increase the intention of risk financial strategy. For intention of risk financial strategies within pro-environmental behavior, the efficiency of enhancing local attachment was higher than that of risk perception.

Power electronic devices are the basis of power converters, and excellent device performance improves that of power converters directly. In this paper we take SiC MOSFET CAS120M12BM2 (1200V/ 120A) and Si IGBT FF150R12KE3G (1200V/150A) as examples, which have the same voltage rating, to apply to the converters of urban rail vehicles, whose switching frequency, power density and efficiency are analyzed and contrasted. The results show that the switching frequency of the SiC MOSFET converter can be increased to 50kHz, at the same time its power density and efficiency are significantly higher than that of the Si IGBT converter.

Two-dimensional metal–organic framework (MOF) nanosheets are utilized as effective enzyme inhibitors, providing an inspiring means to enhance the control of cellular processes as well as improve our understanding of the surface chemistry between MOFs and enzymes. In this paper, we demonstrated that the activity of α-chymotrypsin (ChT) can be effectively inhibited with 96.9% inhibition by 2-D Cu(bpy)2(OTf)2 nanosheets, while Zn2(bim)4 nanosheets show no significant inhibition effect toward ChT. Kinetic studies revealed that the material acts as a competitive inhibitor toward ChT. Furthermore, fluorescence and circular dichroism spectroscopy reveal that the 2-D MOF nanosheets do not change the secondary structure of the enzyme. The Cu(II) center of the 2-D nanosheets binds the 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) molecules in the buffer, leading to an electrostatic interaction between the nanosheets and the enzyme. In addition, the irreversible coordination interactions between Cu(II) ...

Extreme weather events have increased due to climate change. Bioretention basins can effectively alleviate urban flooding by short-term water retention. Reclaimed water (RW) is considered an alternative water resource during water shortages. In this study, the abilities for waterlogging tolerance of four herbaceous flowers (angelonia, narrow-leaf zinnia, celosia, and medallion flower) are investigated to screen suitable ornamental plants for bioretention basins, and the influence of RW on the plants is also evaluated. All plants were treated with 10 days of waterlogging (electrical conductivity (EC) of tap water = 110.0 &mu, S&middot, cm&minus, 1) followed by a seven-day recovery. Angelonia (Angelonia salicariifolia Humb. &amp, Bonpl) was not affected by waterlogging and showed the best performance, judged from the ornamental quality, photosynthesis rate, and leaf malondialdehyde (MDA) among the tested flowers. Photosynthesis of the narrow-leaf zinnia (Zinnia angustifolia Kunth) decreased during waterlogging but soon recovered after being drained. Celosia (Celosia argentea L.) and medallion flower (Melampodium paludosum Kunth) were significantly affected by waterlogging and did not recover after drainage, in terms of responses to both external and physiological reactions. Moreover, waterlogging by the simulated RW (EC = 542.4 &mu, 1) did not have negative impacts on angelonia and narrow-leaf zinnia, due to the reduced leaf malondialdehyde concentration of angelonia and retarded the decline in the net photosynthesis rate of narrow-leaf zinnia. Thus, RW could be used as an alternative irrigation water resource for bioretention basins during the dry season to maintain plant growth.

We proposed some exfoliated Ti-based metal-organic frameworks (MOFs) nanosheets as matrices with ultrahigh ionization efficiency, free matrix background, significant dispersibility and acidic resistance. Combining the features between MOFs and 2-D nanomaterials, the NTU-9 nanosheets matrix also demonstrated suitable band gap energy and superior photoabsorption properties, much better than other representative MOFs. A wide range of small molecules that involving low mass region were also analyzed with NTU-9 nanosheets as the matrices in both positive-ion and negative-ion reflector modes. The ultra-efficient NTU-9 nanosheets matrix was successfully applied to serum for quantitative determination of glucose as a clinical diagnosis indicator of diabetes mellitus.

Spatial correlation of pollution of the water resource in Taipei, Taiwan, were examined by analyzing the antibiotic resistance patterns (ARPs) of 96 Escherichia coli colonies, which were isolated from 7 sampling sites in 3 river sections. The ARPs were the growth patterns of isolated E. coli colonies in the medium with seven kinds of antibiotics, including ampicillin, chlortetracycline, erythromycin, oxytetracycline, streptomycin, tetracycline, and salinomycin of different concentrations. The results showed that the survival rate of E. coli decreased with increasing concentration of antibiotics; however, various ARPs under different antibiotics of different concentrations significantly increased both the useful information and complexities. Hierarchical cluster analysis (HCA) and two-stage principal component analysis (PCA) were applied to analyze the spatial correlations and interrelations of distinct ARPs among sampling sites in this study. It was found that the seven sampling sites can be categorized into three groups which may represent three possible pollution characteristics.

Decabromodiphenyl ether (DBDE), which has been identified as an endocrine disrupting compound, is used as brominated flame retardant, and this can result in serious bioaccumulation within ecological systems. The objective of this study was to explore DBDE bioremediation (25 mg/kg) using laboratory scale soil slurry microcosms. It was found that effective biodegradation of DBDE occurred in all microcosms. Various biometabolites were identified, namely polybrominated diphenyl ethers congeners and hydroxylated brominated diphenyl ether. Reductive debrominated products such as tri-BDE to hepta-BDE congeners were also detected, and their total concentrations ranged from 77.83 to 91.07 ng/g. The mechanism of DBDE biodegradation in soil slurry microcosms is proposed to consist of a series of biological reactions involving hydroxylation and debromination. Catechol 2,3-oxygenase genes, which are able to bring about meta-cleavage at specific unbrominated locations in carbon backbones, were identified as present during the DBDE biodegradation. No obvious effect on the ecological functional potential based on community-level physiological profiling was observed during DBDE biodegradation, and one major facultative Pseudomonas sp. (99 % similarity) was identified in the various soil slurry microcosms. These findings provide an important basis that should help environmental engineers to design future DBDE bioremediation systems that use a practical microcosm system. A bacterial-mixed culture can be selected as part of the bioaugmentation process for in situ DBDE bioremediation. A soil/water microcosm system can be successfully applied to carry out ex situ DBDE bioremediation.

A pH-sensitive controlled release system was proposed in this work, which consists of mesoporous silica nanoparticles (MSNs) functionalized on the pore outlets with poly(4-vinylphenybronic acid-co-2-(dimethylamino)ethyl acrylate) [P(VPBA-DMAEA)]. Four kinds of P(VPBA-DMAEA)-gated MSNs were synthesized and applied for the pH-sensitive controlled release. The results showed that P(VPBA-DMAEA) can work as a pH-sensitive nanovalve. The release behavior of the hybrid nanoparticles could be adjusted by changing the mole ratio of VPBA and DMAEA. With the increasing of the mole ratio of VPBA, the leakage of the entrapped molecules in the pores of MSNs could be decreased at neutral and alkaline conditions. By altering the pH of buffer from 4.0 to 8.0, the valve could be switched “on” and “off” reversibly. In addition, cells viability results indicated that these P(VPBA-DMAEA)-gated MSNs had good biocompatibility. We believe that these MSNs based pH-sensitive controlled release system will provide a promising nanodevice for sited release of drug delivery.

This research aims to analyze the variations of microbial community structure under anaerobic corrosive conditions, using molecular fingerprinting method. The effect of adding various materials to the environment on the corrosion mechanism has been discussed. In the initial experiment, sulfate-reducing bacteria (SRB) were inoculated in a series of batch culture flasks containing sterile growth media. Several testing coupons of mild steel were placed into the SRB-enriched columns, which contained excess sulfate and lactate. After incubating for 20 days, three materials (MgO2, H2O2 and NaOCl) were added into the flasks so as to observe the effects on biocorrosion rate. Microorganism composition change was observed from the diversity profile using the PCR-DGGE (polymerase chain reaction - denaturing gradient gel electrophoresis) method. The results showed that hydrogen peroxide (H2O2) prompted the microbial community to change quickly and easily and enhanced the corrosion rates of coupons (3-6 times faster than the control run). This fact suggested that adding H2O2 could inhibit biological activities initially; however, it ultimately caused more serious corrosion due to breaking down the protective layer, composed of mainly FeS. When MgO2 was added into the SRB-enriched culture, the corrosion rate on the mild steel test coupons was inhibited to one third of that in the control column. The DGGE profile analysis shows that SRBs were clearly inhibited for a long time (more than 100 days) after adding MgO2. The durability of the MgO2 reaction could be demonstrated by DGGE variations as well as water quality monitoring results.

This study examined naphthalene (NAP) biodegradation in the presence of organoclays (Ca-Mon) modified by two nonionic surfactants (TX-100 and Brij 35). The nonionic surfactants are adsorbed onto the clay and this provides extra organic matter, which then generates a partition effect that affects NAP biodegradation. NAP biodegradation was found to be affected by the presence of monomer (MN) or micelle (CMC) surfactant-modified organoclays. The pseudo first-order rate constants for NAP biodegradation were as follows: NAP-Brij35-MN > NAP-Brij35-CMC > NAP > NAP-TX-100-MN > NAP-TX-100-CMC, exactly opposite to the soil organic carbon–water partitioning coefficient (koc) values for NAP in the presence of different nonionic surfactants. The bacterial community and physiological characteristics of PAH biodegradation were different between the free-living bacteria and the particle-attached bacteria and was not associated with the surfactant used. The dominant free-living bacteria involved in NAP biodegradation were Brevundimonas diminuta, Caulobacter spp., Mycoplana bullata, Acidovorax spp. and Pseudomonas aeruginosa. Community-level physiological profiling showed significant differences between free-living bacteria and particle-attached bacteria. Significant extracellular enzyme activities, such as esterases and phosphatases, were associated with the TX-100-MN/CMC modified organoclays. Practically, the results suggest that Brij 35 MN-modified organoclay is the most suitable substrate when using a nonionic surfactant for NAP bioremediation.

The effect of ORP (oxidation–reduction potential) on the bacterial community and corrosion rate was investigated in this study. A continuous sulfate-reducing bacteria (SRB)-enriched reactor equipped with an ORP controller was operated from anaerobic to anoxic condition in this bio-corrosion experiment for over 200 days. Testing mild steel coupons were placed into the reactor for immersion test which was used to compare with the result of electrochemical corrosion current density. The results showed that as the ORP increased, the sulfide, corrosion current density and the proportion of SRB in microbial community would decrease. This study employed oxygen to change the microbial communities, which successfully enabled heterotrophs to inhibit SRB even under excessive TOC and sulfate inflow conditions. However, from the results of corrosion weight loss it could be discovered that the fact of higher control of ORP leading to better corrosion inhibition was not certain. Once the ORP was controlled to −250 mV, the same result could be achieved as well as the ORP being controlled to −180 mV. In addition to the advantage of energy-saving, controlling ORP at −250 mV can also prevent more corrosion reactions from possibly being caused by other microorganisms in the continuous rising of ORP.

The star cluster ( Pentas lanceolata ) cv. Butterfly was planted in a medium that contained 25 mg/kg cadmium (Cd) with application of varying nitrogen concentrations (0 mM, 8 mM, 16 mM, 24 mM and 32 mM) weekly. Regardless of whether nitrogen was applied, the length of stems, roots, the number of nodes, and thickness of leaves of the test seedlings were inhibited by the presence of Cd in the medium. Initially the Cd in the soil caused the chlorophyll meter readings (CMR) of plants to decrease to an abnormal level. The CMR values of the injured plants then recovered to normal levels after 28 days of 32 mM or 24 mM nitrogen addition (CMR levels 29.4 and 25.7 respectively), while the controls had a CMR of only 15.7. The 32 mM nitrogen treatment obtained the maximum accumulation of Cd concentration (622.9 mg/kg) in the root of the testing plants with a total Cd amount of 27.9 μg. Briefly, nitrogen treatment can improve the phytoremediation of Cd, also can promote the recovery of chlorophyll in leaves. Without inhibition of the flowering, the Pentas lanceolata could preserve their function in the landscape even during the process of phytoremediation.

The objective was to evaluate representative bacterial indicators found in the Nanshih River, a resource having multiple uses including recreation, water supply, and agriculture. Human activities were investigated in order to clarify the relationship between bacterial indicators and point source pollution discharged into this river. The optimal bioindicator was evaluated using four approaches by two-dimensional principal component analysis (PCA), which included ten water parameters, the median river pollution index parameters, bacterial numbers and specific fluorescence in situ hybridization indicators. The results indicate that Bifidobacterium spp. with the range of 1.80 ± 0.96–14.14 ± 1.24% were identified as the best bioindicator for the Nanshih River and these bacteria are able to identify four characteristic groups of point pollution sources using PCA. It is suggested the specific bacterial indicator need to be used for the regular monitoring of the Nanshih River in addition to the present re...

This study investigates carbon emission inventory from the local civil aviation industrys aircrafts, airport ground service vehicles and power consumption within an airport. With the existing data of five years, the operating costs probably added into civil aviation industrys operating costs are estimated and sensitivity of six variables are evaluated with Monde Carlo simulations herein to construct a basis for the policy of carbon trading. The dominant two factors contributing to variation in the cost of carbon trading per takeoff & landing at the Taoyuan Airport and the Taipei Airport are carbon price (71.1%) and number of takeoffs & landings (14.4%) as well as number of takeoffs & landings (38.7%) and carbon price (35.3%), respectively.

Stable 2-D metal–organic framework nanosheets were utilized as a superior clean-background matrix for MALDI-TOF MS analysis of small biomolecules and pollutants in both positive and negative ion modes. The matrix could unusually afford up to 1000 mM of the salt concentrations in the monitoring of the enzymatic hydrolysis of neurotransmitter acetylcholine.

Magnetic photocatalystic particles (MPCs) become an alternative process for water and wastewater treatment due to the high removal rate of organic pollutants and a good recovery. Little information of MPCs on the control of microorganisms was obtained in previous researches. In this study, the synthesized MPCs combined with 365 nm UVA irradiation under a light of 1.0 mW/cm2 were applied to control a typical gram-negative strain Staphylococcus sciuri (99% Identified by the NCBI website), which was isolated from an indoor traditional market in the middle area of Taiwan. As a result, the highest bactericidal efficiency (BE) of MPCs contained 0.50 g magnetic particles in nutrient broth was achieved to 68.18% at 50 mins. Considering to each contribution of bacterial control, UVA irradiation played an important role of BE increased from 34.88% at 10 mins to 63.64% at 50 mins. Photocatalystic reaction provided extra more 11.02% of BE at initial 20 mins. The synthesized MPCs demonstrated good crystallinity of anatase by SEM-EDS and XRF. The 76% MPCs can be recovered by simple magnets after photocatalystic reaction.

Discrimination of hemoglobins with subtle differences was achieved using an aptamer based sensing array. Linear discriminant analysis (LDA) showed that the sensing array can discriminate human hemoglobins from hemoglobins of different species.

Thin films with the high content of Ti coated on the stainless steel (SS) sieves were successfully prepared through the sol gel method. Photocatalytic reaction on the TiO2-coated SS sieves with UVA (ultraviolet light with the range of 315-400 nm) radiation is effective to destroy three selected bacterial strains with log-phase period. As a result, bactericidal ability was achieved to 77% in aqueous media. Amount of bacterial numbers, 3.4×107CFU/ml can be removed in this study, compared with our previous study, 1.85×103CFU/ml in the air media. Good contribution of bactericidal ability in 385 nm UVA radiation or heavy metals including Fe, Mn, Cr, Ni and Ti from the SS sieve was obtained as the range of 30-76%. The percentage of 10-17% contribution of bactericidal ability was increased with the photocatalytic reaction additive. It concluded the performance of bactericidal ability in aqueous solution is ascribed to the combination of UVA radiation, heavy metals on the sieve and photocatalytic reaction. The SS sieve coated with TiO2particles can be applied as a disinfectant for the effluent of wastewater treatment plant or water supply system in the future.

The TiO2 nanotube array thin films were fabricated on pure Ti plates by anodization process and annealed at 450oC, 500oC and 550oC for 30 minutes, respectively. The methylene blue (MB) degradation test was further conducted to evaluate the effects of annealing on the photocatalytic ability of TiO2 nanotube array. It was observed that better photocatalytic ability was found for the thin film annealed at 450oC, which was mainly the anatase phase. On the other hand, the anatase/rutile mixed phases were discovered on thin films annealed at 500oC and 550oC, respectively. In this work, the photocatalytic ability of TiO2 nanotube array with mixed anatase/rutile phases was not comparable to that reported in literature. It was suggested that the MB degradation ability was not only related to the crystallinity structure, but also strongly influenced by the surface characteristics of TiO2 nanotube array thin film.

The magnetic photocatalysts (MPCs) can provide both a high specific surface area and an alternative for recovering used catalyst from treated water by the application of a magnetic field. In this study, the Fe3O4particles were synthesized by co-precipitation under alkaline condition. After annealing, the suspension of magnetite particles can be separated by magnet. The magnetite particles were dried and then mixed with TTIP (titanium tetraisopropoxide) for sol-gel method. The MPCs were then achieved after dried and calcined in 300°C. The MPCs synthesized in this study can be separated from treated water by a simple magnet. The photocatalytic abilities of synthesized MPCs were evaluated by measuring the residual methylene blue (MB) amounts after irradiation under a light intensity of 1.0 mW/cm2at 365 nm. The results showed that the synthesized MPCs had good crystallinity of anatase and magnetite. The MPCs can be separated by a simple magnet and did not reduce the photocatalytic abilities significantly. With the advantages of reusability, durability, and separability the synthesized MPCs in this study appear a good alternative for water treatment and widely other potential applications. A MPC with an optimal Fe/Ti ratio and smaller particle size is expected to perform a more practical alternative on water treatment in the future.

In this work, different positive voltages of a pulsed waveform, time intervals and electrolyte stirring were used to prepare by anodization of pure titanium plates, a series of TiO2 thin films based on nanotubes with different morphologies and dimensions. Electrolyte stirring results in large size TiO2 nanotubes with uneven surface morphology and less oriented directions. The titanium plates containing the TiO2 thin films were further annealed at 450 °C for 30 min under air. It was found that only crystalline anatase was formed under this condition. Both methylene blue degradation and antibacterial tests against Escherichia coli were performed to evaluate the photocatalytic performance of these TiO2 films. Better methylene blue degradation ability was achieved by TiO2 nanotubes prepared under electrolyte stirring. However, the antibacterial ability of the annealed TiO2 nanotubes was affected by their inner diameter rather than their length. It is also concluded that the anodized TiO2 nanotube arrays fabricated in this work are promising for photo-induced methylene blue degradation and bacteria killing applications.

Solvothermal reactions of CdSO4·8/3H2O with 1,3,5-tris(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene (titmb) and HCl in H2O, MeOH or EtOH afforded three coordination complexes [Cd5Cl2(μ-Cl)4(μ3-Cl)2(η,η,η-μ3-SO4)2(H2O)2(Htitmb)2]n (1), [Cd4Cl2(μ-Cl)2(η,η,η-μ3-SO4)2(MeOH)2(titmb)2]n (2) and [Cd4Cl2(μ-Cl)2(η,η,η-μ3-SO4)2] (3), respectively. All the compounds were characterized by elemental analysis, IR and single crystal X-ray diffraction. Compound 1 has a 1D chain in which each centrosymmetric double butterfly-shaped [Cd5Cl2(μ-Cl)4(μ3-Cl)2(H2O)2] unit interlinks with its equivalent ones via two couples of η,η,η-μ3-SO4 anions and two pairs of the Htitmb ligands. Compound 2 consists of one centrosymmetric [Cd5Cl2(μ-Cl)2(η,η,η-μ3-SO4)2(MeOH)4(titmb)2] unit that interconnects with equivalent ones via sharing Cd3 and its symmetry-related ones, forming a 1D zigzag chain. Compound 3 consists of a [Cd4Cl2(μ-Cl)2(η,η,η-μ3-SO4)2] unit linked by a pair of titmb ligands. The results may provide some insight into solvent effects on the formation of different coordination compounds from the same components.

Stainless steel (SS) 304 sieves are characterized by their high permeability and high surface area, which can be flexibly used in different photochemical reactor designs. In this work, low pressure plasma cleaning methods in Ar or N2 atmospheres were adopted to clean the surfaces of sieves prior to the deposition of TiO2 coatings by sol–gel and dipping methods. Heat treating at 200 °C was employed after the deposition process. The surface morphologies, crystalline structures and chemical compositions of TiO2 coated sieves were further analyzed. The antibacterial properties of sieves were also evaluated, using the bioaerosol residual test. It was obvious that all TiO2 coated sieves exhibited adequate bactericidal efficiency, destroying over 98% of bacteria. For TiO2 coated #100 and #300 mesh sieves without plasma cleaning, good TiO2 adhesion and at least 98% bactericidal efficiency were observed. The bactericidal efficiency of sieves also increased with increasing Ti content of coatings. In addition, the surface morphologies and chemical compositions of Ar plasma pre-cleaned and TiO2 coated sieves were unchanged even after being sterilized 5 times, which is very useful in the rapid temperature change environments. It is concluded that the Ar plasma pre-cleaned and TiO2 coated SS 304 sieve is a simple, economic and flexible coating method, which is easy for technical transferring and promising in the application of environmental protection fields.

Nine kinds of nanostructured Cr2N/Cu multilayer thin films were deposited by the bipolar asymmetry reactive pulsed DC magnetron sputtering system. The antibacterial tests of coatings with various bilayer periods (Λ) and different Cr2N/Cu thickness ratios were performed to evaluate the bactericidal ability by E. coli, S. aureus and P. aeruginosa, respectively. The Λ value, thickness values of Cr2N to Cu layers significantly affected the bactericidal rates. The 100% bactericidal rates were achieved when the Λ value reached 20 nm. For the same Λ = 12 nm Cr2N/Cu multilayered coatings, the thickness ratio of Cr2N to Cu also showed strong influence on the bactericidal rates.

Four new [Cu n I n ]-based coordination polymers, [{ Cu4(µ3-I)4(mbbm)2}·2DMF] n (1), [(CuI)2(mbbm)2] n (2), [{Cu2(µ-I)2-(ebbm)2}·2MeCN] n (3), and [Cu2(µ-I)2(prbbm)2] n (4), were prepared from solvothermal reactions of CuI with three flexible ligands [(bzim)(CH2) n (bzim)] (bzim = benzimidazole; n = 1, mbbm; n = 2, ebbm; n = 3, prbbm). These compounds were characterized by elemental analysis, IR and X-ray crystallography. 1 consists of cubanelike [Cu4(µ3-I)4] fragments that link the neighboring ones via mbbm bridges to form a 1D ladder-type chain. 2 contains mononuclear [CuI] fragments that are bridged by mbbm ligands to yield a 1D zigzag chain. 3 or 4 contains a [Cu2(µ-I)2] dimeric fragment, which works as a four-connecting node to link its four equivalent ones to form a 2D (4,4) network (3) or acts as a two-connecting node to connect its two equivalent ones via two pairs of prbbm bridges to form a 1D double chain (4). The photoluminescent properties of 1–4 in the solid state at ambient temperature were investigated.

The Dye-Sensitized TiO2 thin film fabricated by TiO2 nanoparticles is a novel technology with advantage in low cost, little pollution and simple in manufacturing process. The fiber-shaped reacting sites provide enlarged photo-sensing area of the TiO2 thin films. Natural dye of TCPP was applied to improve the photo absorbability in this study. Besides, a novel plasma surface activation technique employed on the thin film showed well performance compared with previous reports by heating methods. The SEM images demonstrate that the nano-TiO2 composites deposited on the fiber substrate. Degradation of acetone under 365 and 420 nm light irradiation were conducted to evaluate the photocatalytic ability of the TiO2 and TCPP/TiO2 thin films. While TiO2 thin films gel catalyst showed good photocatalytic performance with a high degradation efficiency of 99.9%, only about 80% conversion efficiency was achieved by the TCPP/TiO2 thin films reactor under 365 nm light irradiation. Although the TCPP dye on TiO2 nanoparticle shows beneficial reflection intensity in 420 nm, the acetone degradation capability of TiO2 and TCPP/ TiO2 thin films reactor decreased about 30% and 25% respectively compared with the degradation efficiency under 365 nm.

Pd/SDB (Styrene Divinylbenzene Copolymer), a hydrophobic catalyst, has been used for the destruction of volatile organic compounds (VOCs) in wastewater. Although the catalysts performed well in low VOC concentrations, they were not as effective in high VOC concentrations because of the heat removal problem. On the other hand, Pt/Zeolite contains a high silica to alumina ratio, which gives it hydrophobic characteristics and allows it to endure significantly higher temperatures than Pd/SDB. Hence, they were chosen for the treatment of wastewater containing high VOC concentrations. As expected, the catalysts presented both high conversion rates and good stability maintenance. Because of their high stability and rapid regeneration, the catalysts were regarded to be promising for industrial applications. In this study, the noble metal content of Pt/Zeolite amounted to 1.5 wt.%, and that the different temperatures and pressures collocating with different weight hourly space velocity (WHSV) were used to test the VOCs conversion efficiency. The results showed that the best reduction temperature was 450°C below the temperature- programmed reduction (TPR) process. The reaction system consisted of a continuous dripping flow with a fix-bed system and proportional integral derivative (PID) temperature controller. Selected VOCs such as methanol, ethanol, propanol and formaldehyde were investigated over the catalyst. Qualitative and quantitative analysis of the reagents and the potential organic intermediates was determined using gas chromatography with a flame ionization detector (FID). The experimental results indicated that the reaction rate is inversely proportional to the molecular weight for the compounds with the same functional group. For the same molecular weight, aldehyde is easier to destroy than alcohol. Ethanol and propanol, atypical products of incomplete oxidation of alcohols, were detected in the reaction gas. To minimize the energy consumption, we preferred liquid phase reaction since the heat of reaction could maintain the reaction temperature.

The La/TiO2 photocatalyst was prepared by lanthanum into TiO2 structure in a sol-gel process. The catalyst was characterized by field-emission scanning electron microscope (FE-SEM), X-ray diffractometer (XRD), ESCA, and Brunauer Emmett Teller (BET) analyses. Photocatalytic activities of the supported catalysts were examined through decomposition process of azo-dye Acid Yellow 17 solution under UV irradiation. The results showed that the particle size of TiO2 is about 20 nm, and the particle of La/TiO2 is about 10 nm. The crystal structure is mainly in anatase phase, the contents of the rutile phase increase with the increase of the amount of doped lanthanum. The adsorption capacity of La/TiO2 catalysts increases with lanthanum dosage in the acidic solution. The contribution of actual photodecomposition was determined by desorption process, after the photocatalytic reaction. In the acidic solution, better photodecomposition efficiency is achieved than in the neutral or alkaline solution. The experiments demonstrated that the optimum doping of La at 10 mol %, the maximum photodecomposition in dye concertration at 15 mg L-1 and photocatalytic dosage at 0.75 g L-1, achieving the highest effect.

The magnetic photocatalysts can provide both a high specific surface area and an alternative for recovering used catalyst from treated water by the application of a magnetic field. In this study, the Fe3O4 nanoparticles were synthesized by co-precipitation. After chemical co-precipitation of ferric and ferrous solution under alkaline condition, the suspension of magnetite nanoparticles were then mixed with TEOT (Titanium (Ⅳ) ethoxide) for sol-gel coating. The separated MPCs (magnetic photocatalyst nanoparticle) were then dried and calcined in 400oC. Magnetic properties of MPCs were identified by superconducting quantum interference device magnetometer (SQUID). The bactericidal ability of synthesized MPCs was evaluated by counting the residual numbers of E. coli after irradiation under a light intensity of 1.0 mW/cm2 at 365 nm. The results show that the MPCs were both anatase and had good crystallinity with clear peaks and insignificant noises after calcination. The SQUID test also reveals that calcination only affects the magnetic susceptibility of the MPC nanoparticles slightly (< 8%). The bactericidal ability of the synthesized MPCs was compared with the commercial TiO2 nanoparticle DegussaTM P25; P25 provided a faster inactivation rate for E. coli in water than MPCs did at the same dosage. The calculated photocatalytic bactericidal rate by P25 is about 3.6 times faster than that by MPCs synthesized in this work. However, the bactericidal rate of magnetic TiO2 synthesized in this work was 5 times than that of other MPCs in the literature. The particles size and surface area of MPCs from this work were about 135 nm and 210 m2/g, respectively. The MPCs from this work have much smaller size and larger surface area; hence there are more active sites for bactericidal reaction.

The study combined UV/TiO2 with ultrasonic procedure to degrade azo dye wastewater of Acid Yellow 17. The effects of factors including pH value, initial concentration of dye, and quantities of TiO2, Fe (II), and Fe (III) added on the removal efficiency of azo dye Acid Yellow 17 were investigated. Experimental results revealed significant additive effect attributed to the combination of two procedures under 13-watt UV irradiation and 10-watt ultrasound. Analysis of the catalyst properties indicated no evident changes in the appearance of crystal and TiO2 catalyst by UV/TiO2 combined with ultrasonic procedure. However, the specific surface area was increased by approximately 53%. No effective formation of hydrogen peroxide (ND  1 mg/L) proved that the addition of Fe (II) and Fe (III) failed to induce the Fenton-like reaction effectively. Nevertheless, the addition of Fe ions affected significantly the initial adsorption and the degradation rate of the dye. Moreover, the treatment efficiency of Fe (III) was found to be superior to that of Fe (II) under the same concentration.

In this study, the Taguchi method was used to optimize the preparation of titanium dioxide thin film reactor through modified chemical vapor deposition (CVD) method and then conversion ratio of toluene was evaluated at the optimal condition. The results indicated that optimal condition for preparation of TiO2 thin film reactor was as followings: water bath temperature of 80°C, Ti (OC3H7)4 / H2O ratio of 4, carrier gas flow rate of 1000 mL min-1, catalytic oxidation temperature of 400°C, oxidation time of 8 hrs, calcination temperature of 450°C, spraying speed of 30 rpm and furnace linear motion geared motor speed of 75 cm min-1. The conversion ratio of 56.56 ppmv toluene could be achieved up to 99.8% with the irradiation intensity of 3.76μW cm-2 at the flow rate of 300 mL min-1 after 120 minutes.

TiO2 thin films obtained by sol-gel and dipping deposition on glass fibers substrates followed by thermal treatment was used in this works. In an attempt to understand the structure and the morphology of TiO2 sol-gel thin films, analysis by X-ray diffraction (XRD) and scanning electron microscopy (SEM) are reported. Degradation of toluene under 365 nm light illumination was conducted to evaluate the photocatalytic ability of the TiO2 thin films. A special design of glass reactor allowed the UV lamp to be located in the center of the reactor. The photocatalyst reactor was then filled with TiO2 thin films/glass fibers substrates to exams the photocatalysis of toluene vapor ranged from 10 to 1,000 ppmv. Toluene depletion was sampled by gas chromatography (GC). The results showed that the photocatalytic performance of the reactor had high toluene depletion efficiency of 99.9% under 20 ppmv, and the efficiency decreased when toluene concentration were 100 and 1,000 ppmv. The improvement of the photocatalytic activity was ascribed to the fibers-based reactor provides a significantly huge surface area of the TiO2 thin films. These results will be useful and assist engineers to design photocatalyst reactors for the VOCs removal.

This paper proposes a method for hiding an important image in a cover image whose size is limited. In this method, in order to save space, a modified search-order coding (MSOC) technique first transforms the important image, then, a randomization procedure permutes the transformed image to further increase the security. Finally, a modulus function embeds the permuted code in a cover image; notably, in the modules function, the modulus base used for a pixel is determined according to the variance of its neighboring pixels. Experimental results show that the images are of high quality. Comparisons with reported methods are provided.

The nanocomposite Cr–Cu–N thin films with Cu content ranging from 1.6 to 24.3 at.% have been deposited by a bipolar asymmetric pulsed DC reactive magnetron sputtering system. A strong CrN (200) texture is found for each coating. The columnar structure was replaced by a dense and compact morphology when the coating contained more than 8.2 at.% Cu. An unusual hardness enhancement is observed on the coating with 15.7 at% Cu, which is possibly due to its grain refinement effect. For the coating containing 15.7 at.% Cu, a combination of high hardness, low coefficient of friction and good antibacterial properties are achieved. The Cr–Cu–N nanocomposite thin film developed in this study with sufficient hardness and antibacterial abilities can be used as a promising candidate to deposit on the surfaces of medical apparatus and food processing equipments.

This work evaluates the addition of solid phase oxygen, a magnesium peroxide (MgO(2)) formulation manufactured by Regenesis (oxygen-releasing compounds, ORC), to inhibit the production of hydrogen sulfide (H(2)S) in an SRB-enriched environment. The initial rate of release of oxygen by the ORC was determined over a short period by adding sodium sulfite (Na(2)SO(3)), which was a novel approach developed for this study. The ability of ORCs to control H(2)S by releasing oxygen was evaluated in a bench-scale column containing cultured sulfate reducing bacteria (SRB). After a series of batch tests, 0.4% ORC was found to be able to inhibit the formation of H(2)S for more than 40 days. In comparison, the concentration of H(2)S dropped from 20 mg S/L to 0.05 mg S/L immediately after 0.1% hydrogen peroxide (H(2)O(2)) was added, but began to recover just four days later. Thus, H(2)O(2) does not seem to be able to inhibit the production of sulfide for an extended period of time. By providing long-term inhibition of the SRB population, ORC provides a good alternative means of controlling the production of H(2)S in water.

In this study, the inhibition of a membrane‐attached biofilm reactor (MFSB) by oxygen was investigated. Results show that the denitrification rate, under anoxic conditions, of the MFSB was close to that under conditions of DO (dissolved oxygen) as high as 7.7 mg/L in bulk phase. It appears that the inhibition of DO on denitrifying rates is not obvious for the MFSB. Under aerobic conditions, the denitrification rate of a conventional denitrifying reactor decreased to almost one half the rate under anoxic conditions. By preserving stability against DO inhibition, MFSB is a reasonable alternative for a stable denitrification system.

Wastewater microorganisms of nitrification and denitrification were cultivated to compose two biofilm modules, termed the permeable support bioreactor (PSB) and the membrane feeding substrate bioreactor (MFSB). PSB and MFSB were combined in a single tank to develop a double-biofilm reactor, which was used to treat nitrogen contaminants in wastewater. With a membrane supplement of substrates (O 2 and CH 3 OH), the D.O. and COD levels were at a low value in the bulk solution thus inhibitive effects between nitrification and denitrification were minimized. Simultaneous nitrification/denitrification was conducted in the reactor and the double-biofilm reactor achieved high nitrification and denitrification efficiency, of 96.5% and 82%, respectively.

Aims: To develop a laboratory-scale autotrophic membrane-immobilized biofilm reactor to remove nitrogen from drinking water. Methods and Results: A polyvinyl alcohol (PVA) immobilized biofilm, attached to the surface of a silicone tube, was used as the basis of a bioreactor for simultaneous nitrification and denitrification of water. The bioreactor was aerated with air to supply oxygen for nitrification. Pure hydrogen was supplied to the silicone tube and diffused through the membrane wall to feed the biofilm for autotrophic denitrification. The bioreactor was effective for the simultaneous nitrification and denitrification of water after a short period of acclimation, while the biofilm exhibited good resistance to the inhibition of denitrification by dissolved oxygen; the denitrification rate decreased by only 8% as the dissolved oxygen increased from 2 mg l−1 to saturation. Conclusions: By using PVA crosslinked with sodium nitrate to entrap nitrifying and denitrifying sludge on the surface of a silicone tube, a novel bioreactor for simultaneous nitrification and denitrification was developed. In addition to performing as an immobilizing agent to strengthen the biofilm, PVA protected the denitrifying microorganisms to reduce the inhibition by dissolved oxygen under aerobic condition. Therefore, nitrification and denitrification occurred simultaneously within the biofilm. Furthermore, the immobilization technique shortened the acclimation period of the bioreactor. Significance and Impact of the Study: The described space saving and simple to operate bioreactor for nitrogen removal performed autotrophic denitrification to solve the problem of residual carbon in heterotrophic denitrification, and thus is suitable for removing nitrogen from drinking water.