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In this study, a “direct-starting” procedure was used to activate a single-chamber biocathode microbial electrolysis cell (MEC) and the development of a biocathode was studied through output current curves and cyclic voltammograms. It only took 163 h for a successful start-up, and a current density of 14.75 A/m2 was obtained. In the formal hydrogen-production stage, it was found that the biocathode MEC was comparable with the Pt/C cathode MEC in terms of current density and energy efficiency, and the hydrogen recovery, cathodic hydrogen recovery, and hydrogen production rate of the biocathode MEC were 71.22% ± 8.98%, 79.42% ± 5.94%, and 0.428 ± 0.054 m3 H2/m3 · days, respectively, which were slightly higher than those obtained with the Pt/C cathode MEC. Besides, under the effect of applied voltage, the microbial populations in the anodophilic biofilm of MEC (MECan) and the cathodophilic biofilm of MEC (MECca) were less diverse than those of the original aerobic activated sludge (AAS) and the anodophilic biofilm of MEC (MECan). Furthermore, the microbial community structures evidently differed between MECan/MECca and AAS/MFC.

In this study, we have constructed ZnCr-LDH/g-C3N4 composite photocatalysts via in-situ synthesis approach. This composite material was used as catalyst interlayer of BPM to promote water dissociation. Results indicated that the combination of ZnCr-LDH and g-C3N4 could effectively improve the photoelectrocatalytic water dissociation activity. When the experiment time lasted for 1 h, the pH decreased to 1.52 in compartment 2, and increased to 13.11 in compartment 4 by using ZnCr-LDH/g-C3N4 composite catalyst.

In this study, a novel GQDs/PANI/g-C 3 N 4 ternary heterostructure was successfully designed and prepared by an in-situ polymerization and electrostatic self-assembly approach. The prepared GQDs/PANI/g-C 3 N 4 was used as interlayer of bipolar membrane (BPM) to promote water dissociation. Results revealed that GQDs/PANI/g-C 3 N 4 ternary photocatalyst exhibits excellent photoelectrocatalytic performance for water dissociation in BPM.

The practical spreading rate of coatings is very significant for industrial coatings. ISO 3233 is the current standard test method, it is very troublesome and have many factors affected the accuracy and stability of test results (such as mass solid fraction, liquid density, wettability of dry-film, adaptability of impregnation with dry-film, dry-film porosity, etc.). A new test method for the determination practical spreading of coatings by the volume shrinkage rate with dry/wet film is introduced in this paper. All the influencing factors of ISO 3233 have been avoided. Different from the traditional method of calculating the practical spreading by the ratio of dry and wet film thickness, the main factors affecting of the accuracy and stability can be avoided. The comparison between the test results of this method in this paper and ISO 3233, we found that the test results of this method in this paper have high accuracy, the difference between the test results is within ±2%, it is a fast, simple, intuitive test method with high accuracy, and can be used in laboratory or painting shop. This test method in this paper is applicable to almost all liquid coatings or resins on hard flat surfaces after drying, includes coatings formulated above materials which exceed the critical pigment volume concentration (CPVC) which ISO 3233 is not applicable. For coatings with 3D surfaces, larger roughness and elasticity coatings, the coating practical spreading rate can be calculated by appropriate measurement method to measure the dry-film thickness. The method in this paper is not applicable to expandable after dried coatings.

An Ag2O/Ag electrode was prepared through the electrochemical oxidation of sterling silver. This electrode was used as a cathodic electron acceptor in a microbial fuel cell (MFC). The Ag2O/Ag electrode was characterized by scanning electron microscopy, X-ray powder diffraction and linear sweep voltammetry. The maximum voltage output of the MFC with the Ag2O/Ag cathode was maintained at between 0.47 and 0.5 V in 100 cycles, indicating the good regenerative capacity of the Ag2O/Ag electrode. The overpotential loss for silver oxide was 0.021–0.006 V, and the maximum power output, open circuit potential and short circuit current of the MFC were 1.796 W m−3, 0.559 V and 9.3375 A m−3, respectively. The energy required for electrochemical reoxidation ranged from 40% to 55% of the energy produced by the MFC. Results indicated that the Ag2O/Ag electrode could be used as a cathodic electron acceptor in MFCs with excellent stability.

we have successfully prepared the reduced graphene oxide/protonated g-C3N4 (rGO/P-g-C3N4) composites by the electrostatic attraction of oppositely charged. The as-prepared rGO/P-g-C3N4 composites exhibit excellent photoelectrocatalytic activity for water dissociation in the bipolar membrane (BPM), this method could be conveniently applied to evaluate the catalytic performance of rGO/P-g-C3N4.

A series of nano-Mg(OH)2/graphene (Gr) composites was synthesized via simple hydrothermal method using MgSO4·7H2O and graphene oxide (GO) as precursors, hydrazine hydrate as additive. Linear sweep voltammetry tests showed that the 2# composite synthesized from 50 wt.% MgSO4·7H2O and 50 wt.% GO with a surface density of 1.5 mg cm−2 exhibited the best catalytic activity for hydrogen evolution reaction. The 2# composite was utilized as the cathodic catalyst in a microbial electrolysis cell (MEC) to facilitate hydrogen production. In the MEC tests, the nano-Mg(OH)2/Gr cathode was comparable with the Pt/C cathode in terms of current densities and energy efficiency. The hydrogen recovery, cathodic hydrogen recovery and hydrogen production rate obtained with nano-Mg(OH)2/Gr MEC were 71 ± 12%, 83 ± 9% and 0.63 ± 0.11 m3 H2 m−3 d−1, slightly higher than those obtained with the Pt/C cathode MEC. The nano-Mg(OH)2/Gr cathode exhibited good stability, and it was inexpensive (less than 1.7% of the cost of the Pt/C cathode). These results demonstrated that the nano-Mg(OH)2/Gr composite was an effective HER catalyst because of its good catalytic capacity, durability, and low price.

The effects of inoculum species, substrate concentration, temperature, and cathodic electron acceptors on electricity production of microbial fuel cells (MFCs) were investigated in terms of start-up time and power output. When inoculated with aeration tank sludge, this MFC outperformed the cell that was inoculated with anaerobic sludge in terms of start-up time and power output. After running for a certain time period, the dominant populations of the two MFCs varied significantly. Within the tested range of substrate concentration (200–1800 mg L−1), the voltage output increased and the time span of the electricity generation lengthened with increasing substrate concentration. As the temperature declined from 35 to 10 °C, the maximum power density reduced from 2.229 to 1.620 W m−3, and anodic polarization resistance correspondingly dropped from 118 to 98 Ω. The voltage output of MFC–Cu2+ was 0.447 V, which is slightly lower than that achieved with MFC–[Fe(CN)6]3− (0.492 V), thereby indicating that MFCs could be used to treat wastewater containing Cu2+ pollutant in the cathode chamber with removal of organics in anode chamber and simultaneous electricity generation.

An electrostatic self-assembly strategy for the preparation of graphene quantum dots (GQDs) attached to the surface of a glassy carbon electrode (GCE) has been developed. The GQDs were prepared by tuning the carbonization degree of citric acid and characterized by atomic force microscopy, transmission electron microscopy, Raman spectroscopy and UV–vis absorption spectroscopy. In addition, the electrochemical behaviours of hydroquinone (HQ) and catechol (CC) on the resulting modified electrodes were investigated. Under optimum conditions, the as-prepared GQDs modified electrode exhibited high electrochemical activity and good selectivity for the oxidation of HQ and CC, the linear ranges for HQ and CC were 4.0∼600 μM and 6.0∼400 μM respectively, and the detection limit was 0.40 μM and 0.75 μM, respectively. The modified electrode was also applied for the detection of real samples with satisfactory results.

Clivia miniata var. variegata (Cmvv) typically possesses yellow- and green-striped leaves. The striped plant not only has a high ornamental value but also be suitable for photosynthesis and chloroplast development research. Our previous study had revealed that yellow stripes (YSs) of Cmvv leaves contain chlorophyll-less ineffective chloroplasts. However, mechanism of Cmvv variegation is yet to be investigated. In the study, transcriptomes of both the YSs and green stripes (GSs) from single Cmvv leaves were compared using high-throughput sequencing. A total of 688 differential expression genes (DEGs) were identified based on biological replications. The qRT-PCR results indicated that transcriptome profiles accurately reflected global transcriptome differences between YSs and GSs. Subcellular localization analysis suggested that 56 DEG proteins were targeted to chloroplasts, and might be involved in anterograde signaling and leaf patterning. Moreover, the DEGs were mostly enriched in photosynthesis and plant-pathogen interaction KEGG pathways. Meanwhile, there should be coordination interaction between the two pathways. Seven of the eight DEGs involved in photosynthesis KEGG pathway were chloroplast-encoded genes and distributed among different cistrons of chloroplast DNA (cpDNA) large single copy regions (LSC) which are more prone to mutation. It was proposed that the YSs were caused by mutation(s) in cpDNA LSC. Thus, when the primary zygote of Cmvv was chimeric in LSC, leaf might be yellow- and green-striped. The study would give new insights into plant variegation and offers candidate genes to guide future research attempting to breed variegated plants.

A novel photoelectrocatalytic approach for water splitting through an I-BiOCl/bipolar membrane sandwich structure with photoelectro-synergistic catalysis is proposed in this study. The I-BiOCl/bipolar membrane sandwich structure could facilitate separation of photoexcited electrons and holes, thereby promoting the splitting of water, increasing the efficiency of H2 generation and saving energy consumption.

In recent years, companies have been striving for increased visibility and transparency of activities performed in supply chains. Supply chain tracking systems can provide visibility, traceability, and associated information across different stages of a supply chain, which enables competitive advantages. The efficiency and effectiveness of a tracking system are mainly supported by identification, communication, and information technologies in the supply chain. A better understanding of the various tracking technologies is important due to the fact that there is no single technology that completely covers the entire spectrum of needs and operations in the supply chain. However, there are various relevant technologies available in the market for information registration, capturing, and exchange; and in addition, some technologies have different standards to fit into specific industry sector and operation environments. These technologies complement each other in many ways; for example, some are suitable for outer environments while others work seamlessly inside facilities; and some identify objects while others capture information. It is the intent of this article to understand the main characteristics of different technologies, which play a key role in implementing the tracking system in an effective way. We introduce concepts of tracking system architecture and review most relevant identification, communication, and information technologies. Ultimately, we want to provide an overview of tracking technologies in order to assist decision makers in the processes of evaluation and selection of adequate technology for a design of a tracking system. Keywords: supply chain; tracking technologies; identification; communication; information