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1.
Small ; 20(30): e2312116, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38446107

ABSTRACT

Flexible zinc-ion batteries have garnered significant attention in the realm of wearable technology. However, the instability of hydrogel electrolytes in a wide-temperature range and uncontrollable side reactions of the Zn electrode have become the main problems for practical applications. Herein, N,N-dimethylformamide (DMF) to design a binary solvent (H2O-DMF) is introduced and combined it with polyacrylamide (PAM) and ZnSO4 to synthesize a hydrogel electrolyte (denoted as PZD). The synergistic effect of DMF and PAM not only guides Zn2+ deposition on Zn(002) crystal plane and isolates H2O from the Zn anode, but also breaks the hydrogen bonding network between water to improve the wide-temperature range stability of hydrogel electrolytes. Consequently, the symmetric cell utilizing PZD can stably cycle over 5600 h at 0.5 mA cm- 2@0.5 mAh cm-2. Furthermore, the Zn//PZD//MnO2 full cell exhibits favorable wide-temperature range adaptability (for 16000 cycles at 3 A g-1 under 25 °C, 750 cycles with 98 mAh g-1 at 0.1 A g-1 under -20 °C) and outstanding mechanical properties (for lighting up the LEDs under conditions of pressure, bending, cutting, and puncture). This work proposes a useful modification for designing a high-performance hydrogel electrolyte, which provides a reference for investigating the practical flexible aqueous batteries.

2.
Small ; 19(30): e2300688, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37029578

ABSTRACT

The creation of anisotropic nanostructures with precise size control is desirable for new properties and functions, but it is challenging for ionic self-assembly (ISA) because of the non-directional electrostatic interactions. Herein, the formation of size-controllable tetragonal nanoprisms is reported via crystallization-directed ionic self-assembly (CDISA) through evaporating a micellar solution on solid substrates. First, ISA is designed with a crystalline polyethylene oxide (PEO) containing cationic polymer poly(2-(2-guanidinoethoxy)ethyl methacrylate)-b-poly(ethyleneoxide)-b-poly(2-(2-guanidinoethoxy)-ethylmethacrylate) (PGn -PEO230 -PGn ) and an anionic 5,10,15,20-Tetrakis(4-sulfonatophenyl) porphyrin (TPPS) to form micelles in aqueous solution. The PG segments binds excessive TPPS with amplenet chargeto form hydrophilic corona, while the PEO segments are unprecedentedly dehydrated and tightly packed into cores. Upon naturally drying the micellar solution on a silicon wafer, PEO crystallizationdirects the micelles to aggregate into square nanoplates, which are further connected to nanoprisms. Length and width of the nanoprisms can be facilely tuned by varying the initial concentration. In this hierarchical process, the aqueous self-assembly is prerequisite and the water evaporation rate is crucial for the formation of nanostructures, which provides multiple factors for morphology regulating. Such precise size-control strategy is highly expected to provide a new vision for the design of advanced materials with size controllable anisotropic nanostructures.

3.
Environ Sci Technol ; 57(48): 19575-19583, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-37991894

ABSTRACT

China's civil aviation market has rapidly expanded, becoming the world's second-largest. However, the air quality and health impacts caused by its aircraft emissions have been inadequately assessed. Here, we leverage an updated emission inventory of air pollutants with improved temporal and spatial resolution based on hundreds of thousands of flight trajectories and simulate aviation-attributable contributions to ground-level air pollution in China. We find that in 2017, the annual-average aviation-attributed PM2.5 and O3 concentrations were 0.4-1.5 and 10.6-14.5 µg·m-3, respectively, suggesting that aviation emissions have become an increasingly important source of ambient air pollution. The contributions attributable to high-altitude emissions (climb/cruise/descent) were comparable to those at low altitudes (landing and takeoff). Aviation-attributed ambient PM2.5 and O3 exposures are estimated to have caused about 67,000 deaths in China in 2017, with populous coastal regions in Eastern China suffering the most due to the dense aviation activity. We recommend that industrial and policy stakeholders expedite an agenda of regulating air pollutants harmonized with decarbonization efforts for a more sustainable aviation future.


Subject(s)
Air Pollutants , Air Pollution , Aviation , Humans , Particulate Matter/analysis , Environmental Monitoring , Air Pollution/analysis , Air Pollutants/analysis , China
4.
Environ Res ; 221: 115331, 2023 03 15.
Article in English | MEDLINE | ID: mdl-36681142

ABSTRACT

BACKGROUND: Single nucleotide polymorphisms (SNPs) in N6AMT1 and AS3MT are associated with arsenic (As) metabolism, and efficient As methylation capacity has been associated with diabetes. However, little is known about the gene-As interaction on gestational diabetes mellitus (GDM). OBJECTIVE: This study aimed to explore the individual and combined effects of N6AMT1 and AS3MT SNPs with As metabolism on GDM. METHODS: A cross-sectional study was performed among 385 Chinese pregnant women (86 GDM and 299 Non-GDM). Four SNPs in N6AMT1 (rs1997605 and rs1003671) and AS3MT (rs1046778 and rs11191453) were genotyped. Urinary inorganic arsenic (iAs), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) were determined, and the percentages of As species (iAs%, MMA%, and DMA%) were calculated to assess the efficiency of As metabolism. RESULTS: Pregnant women with N6AMT1 rs1997605 AA genotype had lower iAs% (B: 2.11; 95% CI: 4.08, -0.13) and MMA% (B: 0.21; 95% CI: 0.39, -0.04) than pregnant women with GG genotype. The AS3MT rs1046778 and rs11191453 C alleles were negatively associated with iAs% and MMA% but positively associated with DMA%. Higher urinary MMA% was significantly associated with a lower risk of GDM (OR: 0.54; 95% CI: 0.30, 0.97). The A allele in N6AMT1 rs1997605 (OR: 0.46; 95% CI: 0.26, 0.79) was associated with a decreased risk of GDM. The additive interactions between N6AMT1 rs1997605 GG genotypes and lower iAs% (AP: 0.50; 95% CI: 0.01, 0.99) or higher DMA% (AP: 0.52; 95% CI: 0.04, 0.99) were statistically significant. Similar additive interactions were also found between N6AMT1 rs1003671 GG genotypes and lower iAs% or higher DMA%. CONCLUSIONS: Genetic variants in N6AMT1 and efficient As metabolism (indicated by lower iAs% and higher DMA%) can interact to influence GDM occurrence synergistically in Chinese pregnant women.


Subject(s)
Arsenic , Diabetes, Gestational , Humans , Female , Pregnancy , Arsenic/metabolism , Polymorphism, Single Nucleotide , Diabetes, Gestational/genetics , Pregnant Women , Methyltransferases/genetics , Methyltransferases/metabolism , Cross-Sectional Studies , East Asian People , Cacodylic Acid , Site-Specific DNA-Methyltransferase (Adenine-Specific)/genetics , Site-Specific DNA-Methyltransferase (Adenine-Specific)/metabolism
5.
Nano Lett ; 22(6): 2514-2520, 2022 03 23.
Article in English | MEDLINE | ID: mdl-35285648

ABSTRACT

Uncontrolled growth of tumor cells is highly dependent on the energy metabolism. Fasting-mimicking diet (FMD) is a low-calorie, low-protein, low-sugar diet representing a promising strategy for cancer treatment. However, triglyceride stored in adipose tissue is hydrolyzed into free fatty acids and glycerol for energy supply during FMD treatment. Herein, we design a nutrient-sensing nanodrug, VFETX, which is self-assembled with vitamin B1 (VB1), ferrous ions, and etomoxir (ETX). FMD treatment upregulate the expression of VB1 transporters on tumor cells, thereby increasing cellular uptake and tumor accumulation of VFETX. Importantly, treatments of VFETX and FMD synergistically inhibit the energy metabolism in tumor cells and subsequently markedly enhance cytotoxicity of ETX. As a result, VFETX nanodrugs efficiently inhibit the growth of two tumor models in vivo without obvious side effects. This study demonstrates the potential of FMD-assisted nutrient-sensing nanodrugs for cancer therapy.


Subject(s)
Nanoparticles , Neoplasms , Energy Metabolism , Fasting , Humans , Nanoparticles/therapeutic use , Neoplasms/drug therapy , Nutrients
6.
BMC Oral Health ; 23(1): 712, 2023 10 04.
Article in English | MEDLINE | ID: mdl-37794381

ABSTRACT

BACKGROUND: Concentrated growth factor (CGF), a new autologous platelet concentrate, has been widely investigated to the adjunctive treatment of oral diseases. This study aims to evaluate the efficacy of CGF in the surgical treatment of oral diseases. METHODS: MEDLINE, Web of Science, Scopus, Cochrane, and EMBASE databases were searched up to July 2023. Only randomized clinical trials were included. The methodologic quality was evaluated by the Cochrane Risk of Bias Tool. RevMan 5.4 software was used for data analysis. RESULTS: In the treatment of periodontal intrabony defects, bone graft combined with CGF was significantly superior to bone graft (P < 0.01), with mean intrabony defect depth reduction of 1.41 mm and mean clinical attachment level gain of 0.55 mm. In the regenerative surgery of furcation defects, the effect of CGF group was significantly better than control group (P < 0.0001), with mean probing depth reduction of 0.99 mm, vertical bone gain of 0.25 mm, and horizontal bone gain of 0.34 mm. CGF combined with coronally advanced flap (CAF) was more effective than CAF alone (mean keratinized tissue width increase of 0.41 mm, mean gingival thickness increase of 0.26 mm, P < 0.00001), but less effective than connective tissue graft (CTG) combined with CAF (mean root coverage difference of -15.1%, mean gingival thickness difference of -0.5 mm, P < 0.0001). In the alveolar ridge preservation, additional use of CGF reduced horizontal bone resorption by 1.41 mm and buccal vertical bone resorption by 1.01 mm compared to control group (P < 0.0001). The VAS score of CGF group was significantly lower than that of the control group at the 1st and 7th day after oral surgery (P < 0.0001). CONCLUSIONS: CGF can exert a positive adjunctive effect for the regenerative surgery of periodontal intrabony defects, furcation defects, and alveolar ridge preservation procedure. CGF combined with CAF has a better therapeutic effect on gingival recession compared to CAF alone, although it is not as effective as CTG combined with CAF. CGF could promote postoperative healing and pain relief in oral surgery within a week. There is currently not enough evidence to support the clinical benefits of CGF in other oral surgeries.


Subject(s)
Bone Resorption , Furcation Defects , Gingival Recession , Humans , Surgical Flaps/transplantation , Gingival Recession/surgery , Gingiva , Intercellular Signaling Peptides and Proteins/therapeutic use , Treatment Outcome , Tooth Root/surgery
7.
Langmuir ; 38(16): 4894-4905, 2022 Apr 26.
Article in English | MEDLINE | ID: mdl-35421315

ABSTRACT

Surface-enhanced Raman scattering (SERS) has attracted attention because of its enormous potential to detect molecules with low concentrations. The method of fabricating SERS substrates is of great importance for improving the detection resolution. However, SERS substrates with different triangular pyramid tips fabricated by using the tip-based nanoindentation method has not been reported. Here, we prepared arrayed micro/nanocavities on copper-based graphene using the continuous indentation method with a Berkovich tip and a cube-corner tip, which have different face angles. Gold nanoparticles were then sputtered onto the graphene-copper micro/nanocavities to form the Au@GR@Cu micro/nanocavities SERS substrates. The substrates formed using the Berkovich tip and cube-corner tip were labeled B2-B9 and C2-C9, respectively, in which the numbers indicate the machining feed. Rhodamine 6G (R6G) was employed, and the Raman intensities of R6G on the differently arrayed Au@GR@Cu micro/nanocavities were measured. The Raman intensities of R6G were stronger on the pile-ups than on the inverted triangular pyramid cavities. The Raman intensities of R6G were highest on the C2 and B2 structures and lowest on the C9 and B9 structures. The Raman intensities of R6G on the arrayed Au@GR@Cu micro/nanocavities fabricated by the cube-corner tip were stronger than those on the arrayed Au@GR@Cu micro/nanocavities fabricated using the Berkovich tip with the same machining feed. In addition, the electric field intensity and distribution of the B9 and C9 arrayed Au@GR@Cu were simulated using Comsol software. Au@GR@Cu structures fabricated by the cube-corner tip were generated with higher electric field intensities. Furthermore, the relative standard deviations at 1362 cm-1 of R6G were 6.19 and 6.62% on the C2 and C4 surfaces, respectively, showing good homogeneity. The SERS spectra of 10-9 mol/L malachite green solution and 10-6 mol/L carbaryl solution were recognized on the C1, C2, and C4 surfaces on day 1 and after 3 months, respectively. After storage at room temperature for 3 months, the reductions in the Raman intensities were less than 10%, indicating excellent stability. The results showed that the arrayed Au@GR@Cu micro/nanocavities fabricated using the cube-corner tip performed better than those fabricated using the Berkovich tip and exhibited excellent uniformity, availability, and stability, providing great potential for detecting pesticides at low concentrations.

8.
Org Biomol Chem ; 20(40): 7886-7890, 2022 10 19.
Article in English | MEDLINE | ID: mdl-36169012

ABSTRACT

A metal-free divergent synthesis of indole compounds dependent on a reagent via intramolecular C(sp2)-H amination was described. The reaction of 2-vinylanilines with DMSO/SOCl2 at 70 °C was found to give 2-thiomethylindoles, while replacing DMSO with diethyl sulfoxide afforded 2-unsubstituted indoles in a highly selective manner.


Subject(s)
Dimethyl Sulfoxide , Sulfoxides , Amination , Indoles
9.
Environ Sci Technol ; 56(9): 5743-5752, 2022 05 03.
Article in English | MEDLINE | ID: mdl-35418234

ABSTRACT

Economic growth and globalization have led to a surge in civil aviation transportation demand. Among the major economies in the world, China has experienced a 12-fold increase in terms of total passenger aviation traffic volume since 2000 and is expected to be the largest aviation market soon. To better understand the environmental impacts of China's aviation sector, this study developed a real-world flight trajectory-based emission inventory, which enabled the fine-grained characterization of four-dimensional (time, longitude, latitude, and altitude) emissions of various flight stages. Our results indicated that fuel consumption and CO2 emissions showed two peaks in altitude distribution: below 1,000 m and between 8,000 and 12,000 m. Various pollutants depicted different vertical distributions; for example, nitrogen oxides (NOX) had a higher fraction during the high-altitude cruise stage due to the thermal NOX mechanism, while hydrocarbons had a dominant fraction at the low-altitude stages due to the incomplete combustion under low-load conditions. This improved aviation emission inventory approach identified that total emissions of CO2 and air pollutants from short-distance domestic flights would be significantly underestimated by the conventional great-circle-based approach due to underrepresented calculation parameters (particularly, flight distance, duration, and cruise altitude). Therefore, we suggest that more real-world aviation flight information, especially actual trajectory records, should be utilized to improve assessments of the environmental impacts of aviation.


Subject(s)
Air Pollutants , Aviation , Air Pollutants/analysis , Carbon Dioxide , Economic Development , Nitrogen Oxides/analysis
10.
Int J Mol Sci ; 23(22)2022 Nov 14.
Article in English | MEDLINE | ID: mdl-36430507

ABSTRACT

Rice blast is a worldwide fungal disease that seriously affects the yield and quality of rice. Identification of resistance genes against rice blast disease is one of the effective ways to control this disease. However, panicle blast resistance genes, which are useful in the fields, have rarely been studied due to the difficulty in phenotypic identification and the environmental influences. Here, panicle blast resistance-3 (Pb3) was identified by a genome-wide association study (GWAS) based on the panicle blast resistance phenotypes of 230 Rice Diversity Panel I (RDP-I) accessions with 700,000 single-nucleotide polymorphism (SNP) markers. A total of 16 panicle blast resistance loci (PBRLs) within three years including one repeated locus PBRL3 located in chromosome 11 were identified. In addition, 7 genes in PBRL3 were identified as candidate genes by haplotype analysis, which showed significant differences between resistant and susceptible varieties. Among them, one nucleotide-binding domain and Leucine-rich Repeat (NLR) gene Pb3 was highly conserved in multiple resistant rice cultivars, and its expression was significantly induced after rice blast inoculation. Evolutionary analysis showed that Pb3 was a typical disease resistance gene containing coiled-coil, NB-ARC, and LRR domains. T-DNA insertion mutants and CRISPR lines of Pb3 showed significantly reduced panicle blast resistance. These results indicate that Pb3 is a panicle blast resistance gene and GWAS is a rapid method for identifying panicle blast resistance in rice.


Subject(s)
Magnaporthe , Oryza , Genome-Wide Association Study , NLR Proteins/genetics , NLR Proteins/metabolism , Magnaporthe/genetics , Plant Diseases/genetics , Plant Diseases/microbiology , Oryza/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism
11.
J Environ Manage ; 320: 115670, 2022 Oct 15.
Article in English | MEDLINE | ID: mdl-35921747

ABSTRACT

Exploring the removal rules of MFC on composite heavy metal pollution is very important for the future development and field application of MFC. We constructed a three-chamber soil MFC and the results showed that with the gradual deterioration of soil heavy metal contamination from single heavy metal to metals in different oxidation states (e.g., copper (II), lead (II), and chromium (III) compounds), the internal resistance of the soil MFC increased by 2.16-2.71 times, which significantly inhibited the power production performance of the MFC. After 59 days of remediation, the migration removal efficiencies of total Cu, total Cr and total Pb from the soil under composite conditions were 36.69%, 52.35% and 19.67%, respectively. The main removal mechanisms included both electromigration and diffusion, where electromigration contributed 74.41%, 31.48% and 97.67% to the removal of total Cu, Cr and Pb, respectively. The removal of composite heavy metals was affected by adsorption-desorption competition and synergism. The competition of Pb for specific adsorption sites in soil leads to the increase of mobility of Cr and Cu, which is conducive to migration and removal. The migration of Cu and Pb ions to the cathode inhibited the diffusion of Cr to the anode; however, it drove the synergistic migration of Pb ions to the cathode. For the heavy metals migrated from the soil into the catholyte, only Cu2+ with high redox potential is reduced to copper at the cathode.


Subject(s)
Bioelectric Energy Sources , Metals, Heavy , Soil Pollutants , Copper/analysis , Lead , Metals, Heavy/analysis , Soil , Soil Pollutants/analysis , Technology
12.
Antimicrob Agents Chemother ; 65(9): e0095621, 2021 08 17.
Article in English | MEDLINE | ID: mdl-34152815

ABSTRACT

Mycobacterium tuberculosis, the causative agent of human tuberculosis, harbors a branched electron transport chain, preventing the bactericidal action of cytochrome bc1 inhibitors (e.g., TB47). Here, we investigated, using luminescent mycobacterial strains, the in vitro combination activity of cytochrome bc1 inhibitors and nitric oxide (NO) donors including pretomanid (PMD) and explored the mechanisms of combination activity. The TB47 and PMD combination quickly abolished the light emission of luminescent bacilli, as was the case for the combination of TB47 and aurachin D, a putative cytochrome bd inhibitor. The TB47 and PMD combination inhibited M. tuberculosis oxygen consumption, decreased ATP levels, and had a delayed bactericidal effect. The NO scavenger carboxy-PTIO prevented the bactericidal activity of the drug combination, suggesting the requirement for NO. In addition, cytochrome bc1 inhibitors were largely bactericidal when administered with DETA NONOate, another NO donor. Proteomic analysis revealed that the cotreated bacilli had a compromised expression of the dormancy regulon proteins, PE/PPE proteins, and proteins required for the biosynthesis of several cofactors, including mycofactocin. Some of these proteomic changes, e.g., the impaired dormancy regulon induction, were attributed to PMD. In conclusion, combination of cytochrome bc1 inhibitors with PMD inhibited M. tuberculosis respiration and killed the bacilli. The activity of cytochrome bc1 inhibitors can be greatly enhanced by NO donors. Monitoring of luminescence may be further exploited to screen cytochrome bd inhibitors.


Subject(s)
Mycobacterium tuberculosis , Cytochromes , Electron Transport , Electron Transport Complex III , Humans , Nitric Oxide , Nitroimidazoles , Proteomics
13.
Biochem Biophys Res Commun ; 574: 63-69, 2021 10 15.
Article in English | MEDLINE | ID: mdl-34438348

ABSTRACT

Human extended pluripotent stem (hEPS) cell is a newly established human embryonic stem cell (hESC) line with the capacity of chimerizing both embryonic and extraembryonic tissues compared with primed hESCs which are inefficient to contribute to the inner cell mass (ICM). The molecular mechanism underlying the pluripotency of hEPS cells is still not clear. We conducted RNA-seq and ATAC-seq analysis to investigate the differential expression profiling and genomic chromatin accessibility features. According to our data, more than 2000 genes were specially up-regulated in hEPS cells. Furthermore, the open chromatin regions in these two human embryonic stem cell lines were quite different. In hEPS cells, transcriptional factors binding motifs associated with pluripotency maintenance were enriched in chromatin accessible regions. Integrating the results from ATAC-seq and RNA-seq, we identified new regulatory features which were important for pluripotency maintenance and cell development in hEPS cells. Together, these results provided a new perspective on the understanding of molecular features of hESCs in different pluripotent states and a novel resource for further studies on regenerative medicine by using hEPS cells.


Subject(s)
Chromatin/metabolism , Pluripotent Stem Cells/metabolism , Cells, Cultured , Humans
14.
J Org Chem ; 86(14): 9490-9502, 2021 07 16.
Article in English | MEDLINE | ID: mdl-34184892

ABSTRACT

A highly substituent-dependent rearrangement allows for the novel and SOCl2-induced divergent synthesis of 3-methylthioquinolin-2-ones and 3-methylthiospiro[4.5]trienones through intramolecular electrophilic cyclization of N-aryl propyamides. DMSO acts as both solvent and sulfur source, and use of DMSO-h6/d6 enables the incorporation of SCH3 or SCD3 moieties to the 3-position of the heterocyclic framework. Different para-substituents trigger divergent reaction pathways leading to the formation of quinolin-2-ones for mild substituents and spiro[4,5]trienones for both electron-withdrawing and -donating substituents, respectively. On the basis of both computational and experimental results, a new mechanism has been put forward that accounts for the exclusive spirolization/defluorination process and the surprising substituent effects.


Subject(s)
Dimethyl Sulfoxide , Spiro Compounds , Cyclization , Electrons
15.
Nanotechnology ; 33(11)2021 Dec 23.
Article in English | MEDLINE | ID: mdl-34844231

ABSTRACT

The micro-stripe structure was prepared by laser interference induced forward transfer technique, composed of Ag nano-particles (NPs). The effects of the film thickness with the carbon nano-particles mixed polyimide (CNPs@PI), Ag film thickness, and laser fluence were studied on the transferred micro-stripe structure. The periodic Ag micro-stripe with good resolution was obtained in a wide range of CNPs@PI film thickness from âˆ¼0.5 to âˆ¼1.0µm for the Ag thin film âˆ¼20 nm. The distribution of the Ag NPs composing the micro-stripe was compact. Nevertheless, the average size of the transferred Ag NPs was increased from âˆ¼41 to âˆ¼197 nm with the change of the Ag donor film from âˆ¼10 to âˆ¼40 nm. With the increase of the laser fluence from 102 to 306 mJ·cm-2per-beam, the transferred Ag NPs became aggregative, improving the resolution of the corresponding micro-stripe. Finally, the transferred Ag micro-stripe exhibited the significant surface enhanced Raman scattering (SERS) property for rhodamine B (RhB). While the concentration of the RhB reached 10-10mol·L-1, the Raman characteristic peaks of the RhB were still observed clearly at 622, 1359 and 1649 cm-1. These results indicate that the transferred Ag micro-stripe has potential application as a SERS chip in drug and food detection.

16.
Environ Res ; 198: 111217, 2021 07.
Article in English | MEDLINE | ID: mdl-33974843

ABSTRACT

Microbial fuel cells (MFCs) with different electrode configurations were constructed to study the mechanism of influence of multiple current paths on their electrical performance and the removal of heavy metals in soil. Three types of MFCs were constructed, namely, double anode-single cathode (DASC), single anode-dual cathode (SADC), and single anode-single cathode (SASC). The total electricity generation of the three kinds of MFC was similar: 143.44 × 10-3 mW, 114.90 × 10-3 mW, and 132.50 × 10-3 mW, respectively. However, the maximum voltage and cathode current density produced by a single current path differed significantly. The corresponding values were 0.27, 0.23, and 0.42 V and 0.130, 0.122, and 0.096 A/m 2, respectively. The SASC had the best electricity generation performance. Based on a limited reduction rate of oxygen at the cathode, the accumulation of cathode electrons was facilitated by the construction of multiple current paths in the MFC, which significantly increased the cathode electron transfer resistance and limited the electricity generation performance of the MFC. However, at the same time, the construction of multiple current paths promoted output of more electrons in the anode, reducing the retention of anode electrons and anode electron transfer resistance. The heavy metal removal efficiencies of SASC, DASC, and SADC were 2.68, 2.18, and 1.70 times that of the open circuit group, respectively. The migration of heavy metals in the soil depended mainly on the internal electric field intensity of the MFC rather than the total electricity generation. As the internal electric field intensity increased, the removal efficiency of heavy metals in the MFC increased.


Subject(s)
Bioelectric Energy Sources , Metals, Heavy , Electricity , Electrodes , Electrons , Soil
17.
Ecotoxicol Environ Saf ; 192: 110314, 2020 Apr 01.
Article in English | MEDLINE | ID: mdl-32061983

ABSTRACT

As an environmentally sustainable bioelectrochemical technology, the microbial fuel cell (MFC) has attracted great attention. In this study, a three-chamber MFC (TC-MFC) was enhanced with different auxiliary reagents to remove heavy metals from soil. The results showed that the removal efficiency of heavy metals from soil increased with increasing auxiliary reagent concentration. When 1 mol/L citric acid, HCl, or acetic acid were used as an auxiliary reagent, the total copper (500 mg/kg) removal efficiency after 74 days of TC-MFC treatment was 3.89, 5.01 and 2.01 times that of the control group, respectively. The highest soil electrical conductivity (15.29 ms/cm), ionic heavy metal content (94.78%), electricity generation performance (363.04 mW h), and desorption stability of heavy metals were obtained when using 1 mol/L HCl as an auxiliary reagent, indicating that HCl was more suitable for the remediation of heavy metals in soil using a TC-MFC. Correlation analysis showed that the electricity generation of the TC-MFC was linearly related to the removal efficiency of heavy metals from soil (R2 = 0.9296). At the same time, higher content of ionic heavy metals in the soil led to better migration of heavy metals under the internal electric field of the TC-MFC.


Subject(s)
Bioelectric Energy Sources , Metals, Heavy/analysis , Soil Pollutants/analysis , Copper/analysis , Electric Conductivity , Electricity , Environmental Restoration and Remediation , Soil/chemistry
18.
Opt Express ; 23(13): 16782-91, 2015 Jun 29.
Article in English | MEDLINE | ID: mdl-26191690

ABSTRACT

An ultra-thin, planar, broadband metalens composed of L-shaped gap antennas on a thin gold film has been designed, which is suitable for both circular and X/Y linear polarizations focusing simultaneously. The phase discontinuity of the cross-polarized transmisson light can be manipulated by the length and width of the L-shaped gap antenna accurately. The designed planar metalens posses a strong focusing ability over a large wavelength range, and the size of the focus spot is in sub-wavelength scale. The focal lengths change from 13 to 7 um with incident wavelength from 750 to 1300 nm, and the cause of dispersion is explained and analyzed in detail. The designed metalens can work very well at a wide incident angles of 0~45°. Most importantly, its unique focusing ability that is independent of the incident polarizations will greatly promotes the practical applications and developments of the metasurfaces.

19.
Opt Express ; 23(14): 17883-91, 2015 Jul 13.
Article in English | MEDLINE | ID: mdl-26191849

ABSTRACT

A miniature, simplified and planar plasmonic lens based on the circular array of nano-pinholes for on-axis beaming has been proposed and investigated systematically in the visible spectrum. Focusing properties of the designed plasmonic lens illuminated under circular polarized (CP) light for different radius of circular ring, filled with different dielectrics, with different numbers of pinholes have been investigated and analyzed in detail by finite element method (FEM). Our simulated results demonstrate such a miniature single-turn structure can also generate a totally centrosymmetric focusing spot under the CP illumination. Besides, by properly manipulating the filled dielectric and incident wavelengths, enhanced transmission, elongated depth of focus have also be realized, which can be used to modulate the transmitting fields effectively. Such a miniature and simplified plasmonic focusing lens can open up a vital path toward fiber-end planar photonic devices for biosensing and imaging.

20.
Opt Express ; 23(23): 30523-31, 2015 Nov 16.
Article in English | MEDLINE | ID: mdl-26698530

ABSTRACT

A relative broadband circular polarization analyzer based on a single-turn Archimedean nano-pinholes array has been proposed and investigated systematically from visible spectrum to near infrared region. The spiral arrangement of circular nano-pinholes can implement spatially separated fields according to the relationship between the spiral direction of Archimedean structure and chirality of circularly polarized light (CPL). The enhanced-characteristics mechanisms of the single-turn spirally arranged Archimedean pinholes array have been deduced and investigated by the theoretical analysis and numerical simulation in detail. Different from the single operating wavelength of the spiral slit structure, this novel design also shows a relative wide range of the operating wavelengths in the focusing and defocusing effects. The new proposed circular polarization analyzer could find more extensive applications, such as analyzing the physiological properties of chiral molecules based on circular polarizations, full Stokes-parameter polarimetric imaging applications and so on.

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