Boosting Ammonium Oxidation in Wastewater by the BiOCl-Functionalized Anode.

Mixed metal oxide (MMO) anodes are commonly used for electrochlorination of ammonium (NH4+) in wastewater treatment, but they suffer from low efficiency due to inadequate chlorine generation at low Cl- concentrations and sluggish reaction kinetics between free chlorine and NH4+ under acidic pH conditions. To address this challenge, we develop a straightforward wet chemistry approach to synthesize BiOCl-functionalized MMO electrodes using the MMO as an efficient Ohmic contact for electron transfer. Our study demonstrates that the BiOCl@MMO anode outperforms the pristine MMO anode, exhibiting higher free chlorine generation (24.6-60.0 mg Cl2 L-1), increased Faradaic efficiency (75.5 vs 31.0%), and improved rate constant of NH4+ oxidation (2.41 vs 0.76 mg L-1 min-1) at 50 mM Cl- concentration. Characterization techniques including electron paramagnetic resonance and in situ transient absorption spectra confirm the production of chlorine radicals (Cl• and Cl2•-) by the BiOCl/MMO anode. Laser flash photolysis reveals significantly higher apparent second-order rate constants ((4.3-4.9) × 106 M-1 s-1 at pH 2.0-4.0) for the reaction between NH4+ and Cl•, compared to the undetectable reaction between NH4+ and Cl2•-, as well as the slower reaction between NH4+ and free chlorine (102 M-1 s-1 at pH < 4.0) within the same pH range, emphasizing the significance of Cl• in enhancing NH4+ oxidation. Mechanistic studies provide compelling evidence of the capacity of BiOCl for Cl- adsorption, facilitating chlorine evolution and Cl• generation. Importantly, the BiOCl@MMO anode exhibits excellent long-term stability and high catalytic activity for NH4+-N removal in a real landfill leachate. These findings offer valuable insights into the rational design of electrodes to improve electrocatalytic NH4+ abatement, which holds great promise for wastewater treatment applications.

A highly sensitive and fast graphene nanoribbon/CsPbBr3 quantum dot phototransistor with enhanced vertical metal oxide heterostructures.

Although recent breakthroughs in reported graphene-based phototransistors with embedded quantum dots (QDs) have definitely been astonishing, there are still some obstacles in their practical use with regard to their electrical and optical performances. We show that through optimization of the vertical graphene nanoribbon (GNR)/QD/IGZO heterostructure and the ultrahigh efficiency of CsPbBr3 QDs, it is possible to significantly increase the on/off ratio (>103), the subthreshold slope (S.S., 0.9 V dec-1), the device's field effect mobility (µFET, 13 cm-1 V-1 S-1) and other electrical properties. Subsequently, on the basis of the extra optical-electrical characterization, we attribute the enhanced photosensitivity (800), the accelerated detecting speed (141 µs) and the high detectivity (7.5 × 1014 cm Hz1/2 W-1) to the vertical heterostructure associated with the optimized GNR component. To further demonstrate this enhancement phenomenon, the mechanism and theory mode of this vertical heterostructure are analyzed and exploited in this letter. This research indicates that a highly sensitive and fast phototransistor can be realized using the novel GNR/QD/IGZO vertical heterostructure and the long diffusion length of the perovskite QD photosensing component.

High Efficiency Light-Emitting Transistor with Vertical Metal-Oxide Heterostructure.

The monolithic integration of light-emission with a standard logic transistor is a much-desired multifunctionality. Here, a high-efficiency light-emitting transistor (LET) employing an inorganic quantum dots (QDs) emitter and a laser-annealed vertical metal-oxide heterostructure is reported. The experimental results show that the peak efficiency and luminance of this QDs LET (QLET) are 11% and 8000 cdm-2 , respectively at a monochromatic emitting light wavelength of 585 nm. As far as it is known, these are among the highest values ever achieved for LETs. More importantly, the QLET exhibits an ultrahigh electron mobility of up to 25 cm2 V-1 S-1 , a lower efficiency roll-off (7% at high 3000 cdm-2 ), and excellent stability with long-duration gate stress switching cycles. Additionally, this approach is compatible with those used in conventional large-area silicon electronic manufacturing and can enable a scalable and cost-effective procedure for future integrated versatile displays and lighting applications.

Using whole exome sequencing and bioformatics in the molecular autopsy of a sudden unexplained death syndrome (SUDS) case.

Whole exome sequencing (WES) and bioinformatics analysis were used to investigate potential disease-causing gene mutations in a sudden unexplained death syndrome (SUDS) case after autopsy and pathology tests failed to suggest an obvious disease mechanism. Following whole exome sequencing, a 3-step bioinformatics filtering procedure was carried out to identify possible pathogenic genomic features. Single nucleotide variations (SNVs) were analyzed and ranked by likely mutation impact using various open online tools. After screening, we identified G643S as a putative causative heterozygous mutation in the KCNQ1 gene. This mutation has been reported in abnormalities consistent with SUDS, such as IKs in cardiac myocytes, a condition that predisposes for arrhythmias. Our work demonstrates the application of sequencing technology at the whole exome level for determining potential causes of an otherwise unexplained death.

Graphene nanomesh photodetector with effective charge tunnelling from quantum dots.

Graphene nanomesh (GNM)-based optoelectronics integrated with quantum dots (QDs) are investigated in this article. The charge transfer mechanism in the QDs/GNM interface is probed in four terminal gated FET-type photodetectors. The insulating ligand is used to make the GNM/ligand/QDs vertically behave like a metal/insulate/semiconductor (MIS) structure to facilitate the charge tunnelling. With the current constraint effect of the GNM and the effective charge tunnelling, a high-performance photodetector is fabricated with higher responsivity, higher on/off ratio and shorter response time. The results of our analysis and experimental approach can be extended to future graphene-based photodetectors, as long as suitable ligands and an effective architecture are chosen for this type of device.

Genetic polymorphisms of 10 X-STR among four ethnic populations in northwest of China.

In the present study, 10 short tandem repeats (STR) (HPRTB, DXS6789, DXS6799, DXS6804, DXS7130, DXS7132, DXS7133, DXS7423, DXS7424, and DXS8378) on X chromosome were investigated among four ethnic populations (431 individuals) in northwest of China, in order to learn about the genetic diversity, forensic suitability, and possible genetic affinities of the populations. The polymorphism information content (PIC) values for the ten loci range from 0.340 to 0.810, and the observed heterozygosity values for the ten loci range from 0.397 to 0.860, the results indicated that the ten loci have a moderate degree of variability in the four populations, and each population has its own characteristics of genetic structure. A Neighbor-joining (NJ) tree constructed on the basis of the generated data shows very low genetic distance between Han, Mongolian and Tibetan, Dongxiang and Tu as well as between Salar and Bonan populations. Our results based on genetic distance analysis are consistent with the results of earlier studies based on linguistics and the immigration history and origin of these populations. These STR loci on the X chromosome studied here are not only useful in showing significant genetic variation between the populations, but also are suitable for human identity testing among the four populations.

[Genetic differentiation and patterns of gene flow of ten minorities in Yunnan province].

OBJECTIVE: To explore the features of genetic differentiation and gene flow of ten minorities in Yunnan province according to nine CODIS short tandem repeat(STR) loci (CSF1PO, FGA, THO1, TPOX, v WA, D3S1358, D5S818, D7S820 and D13S317). METHODS: Heterozygosity and parameters of population differentiation such as F, theta, f and Gst at each locus were calculated. DA genetic distance and fixation index Fst were calculated by Phylip 3.6 and Arlequin 3.0 software, respectively. Phylogenetic trees were constructed by Mega 3.0, and the patterns of gene flow were analyzed by R-matrix model. RESULTS: It showed that average genetic heterogeneity in ten minorities was above 0.7. Significant difference was found for most of the loci in genetic differentiation. Phylogenetic tree analysis showed that the ten minorities were divided into two clusters. The results of the R-matrix analysis showed that the gene flow of Yi and Dai minorities were higher than that of other minorities, while the pattern of gene flow of Dulong minority demonstrated some of the isolation. CONCLUSION: Nine STR loci commonly used in forensic identification show a high polymorphism. Heterozygosity can be used for investigating genetic differentiation and gene flow of minority. The ten minorities in Yunnan are independent populations, while the level of differentiation is not high. The relationship in evolution is not far from each other and shows a widely gene flow among the minorities.