Investigation of alternative batteries systems beyond lithium-ion batteries

The growing market for portable electronic devices and electric vehicles has created an increasing demand for state-of-the-art Li-ion batteries. Meanwhile, alternatives to current Li-ion batteries are proposed to improve battery safety, energy density, C-rate, etc. Approaches towards such alternatives include the utilization of novel electrolytes, anode and cathode materials, and metal ion charge carriers in the battery system. The work presented here covers the investigation of several alternative battery systems. Double Layer Structure in Water-in-Salt Electrolytes. Water-in-Salt Electrolytes (WiSE) are highly concentrated aqueous electrolytes that are of great interest due to their application potential in batteries. The double-layer structure of this LiTFSI-based aqueous system is investigated on a charged electrode surface. Potential dependent atomic force microscopy (AFM) reveals the presence of layers, the structure of which changes with applied potential. Larger layers (6.4 Å and 6.7 Å) are observed at positive potentials, associated with [Li(H2O)x]+([TFSI]-)y ion pairs, while smaller layers (2.8 Å and 3.3 Å) are found at negative potentials and associated with [Li(H2O)x]+ alone. Vibrational spectroscopy shows the potential-dependent compositional change in the double layer, where [TFSI]- is enriched at positive and [Li(H2O)x]+ enriched at negative potentials, respectively. Electrochemical measurements using macroelectrodes and ultramicroelectrodes (UME) reveal a surface-confinement effect for a ferricyanide redox species at the electrode/WiSE interface. Catalytic Effect of Co Nanoparticles in a Sodium-Sulfur Battery. Room-temperature sodium-sulfur (Na-S) batteries have aroused great interest due to their high energy density and high natural abundance. A new room-temperature Na-S battery system is developed in this work. A MOF-derived Co-containing nitrogen-doped porous carbon (CoNC) is utilized as a catalytic sulfur cathode host. A concentrated sodium electrolyte based on sodium bis(fluorosulfonyl)imide (NaFSI), dimethyoxyethane (DME) and bis(2,2,2-trifluoroethyl) ether (BTFE) is used to facilitate reversible Na electrodepostion and mitigate polysulfide dissolution. The amount of Co present in the CoNC carbon host is tuned by acid-washing. Significant improvement in reversible sulfur conversion and capacity retention is observed with higher Co-content in CoNC, with 600 mAh/g and 77% capacity retention for CoNC, and 261 mAh/g and 56% capacity retention for acid-washed CoNC at cycle 50 at 80 mAh/g. The catalytic mechanism of Co is investigated. Postmortem XPS, TEM and selected area electron diffraction (SAED) reveals that CoS is formed during cycling in place of Co nanoparticles. Raman spectroscopy suggests that CoS exhibits a catalytic effect on the oxidation of Na2S. CoS2 as a Cathode Material for a Non-Aqueous Zn Battery. CoS2 is investigated as a cathode material for a non-aqueous Zn battery. A maximum capacity of 283 mAh/g is obtained from a Zn/CoS2 coin cell. Compositional study reveals a reversible Zn2+ intercalation process. X-Ray photoelectron spectroscopy (XPS) reveals an anionic redox activity mediated by reversible interconversions between 2S2- (sulfide) and S22- (disulfide), which is the first such known case operating in a multivalent system. X-Ray diffraction (XRD) reveals an irreversible phase change upon Zn2+ insertion

Thyroid function and polycystic ovary syndrome: a Mendelian randomization study

BackgroundMultiple evidence suggests that thyroid function is associated with polycystic ovary syndrome (PCOS), but whether thyroid function is causally related to PCOS is unclear. To investigate whether the association reflect causality, a Mendelian randomization (MR) analysis was conducted.MethodsSingle nucleotide polymorphisms (SNPs) involved in this study were acquired from The ThyroidOmics Consortium and the IEU Open Genome-wide association study (GWAS) database, respectively. In forward MR analysis, we included normal free thyroxine (FT4, n=49,269), normal thyroid-stimulating hormone (TSH, n=54,288), hypothyroidism (n=53,423) and hyperthyroidism (n=51,823) as exposure. The outcome was defined as PCOS in a sample size of 16,380,318 individuals. The exposure in the reverse MR analyses was chosen as PCOS, while the outcome consisted of the four phenotypes of thyroid function. The inverse-variance weighted (IVW) method was performed as the major analysis, supplemented by sensitivity analyses.ResultsThe occurrence of PCOS was associated with increased risk of hyperthyroidism (IVW, OR=1.08, 95%CI=1.02-1.13, P=0.004). No evidence suggested that other phenotypes of thyroid function were related to PCOS.ConclusionsOur findings demonstrate a cause-and-effect connection between PCOS and hyperthyroidism. The study established foundation for further investigation for interaction between thyroid function and PCOS

Nematic spin correlations pervading the phase diagram of FeSe1−x_{1-x}Sx_{x}

We use resonant inelastic X-ray scattering (RIXS) at the Fe-L$_3$ edge to study the spin excitations of uniaxial-strained and unstrained FeSe$_{1-x}$S$_{x}$ ($0\leq x\leq0.21$) samples. The measurements on unstrained samples reveal dispersive spin excitations in all doping levels, which show only minor doping dependence in energy dispersion, lifetime, and intensity, indicating that high-energy spin excitations are only marginally affected by sulfur doping. RIXS measurements on uniaxial-strained samples reveal that the high-energy spin-excitation anisotropy observed previously in FeSe is also present in the doping range $0< x\leq0.21$ of FeSe$_{1-x}$S$_{x}$. The spin-excitation anisotropy persists to a high temperature up to $T>200$ K in $x=0.18$ and reaches a maximum around the nematic quantum critical doping ($x_c\approx0.17$). Since the spin-excitation anisotropy directly reflects the existence of nematic spin correlations, our results indicate that high-energy nematic spin correlations pervade the regime of nematicity in the phase diagram and are enhanced by the nematic quantum criticality. These results emphasize the essential role of spin fluctuations in driving electronic nematicity and open the door for uniaxial strain tuning of spin excitations in quantum materials hosting strong magnetoelastic coupling and electronic nematicity.Comment: 6 pages, 4 figures, supplemental materials uploade

Rapid detection of Mycobacterium tuberculosis based on cyp141 via real-time fluorescence loop-mediated isothermal amplification (cyp141-RealAmp)

BackgroundThe rapid detection of Mycobacterium tuberculosis (MTB) is essential for controlling tuberculosis. Methods We designed a portable thermocycler-based real-time fluorescence loop-mediated isothermal amplification assay (cyp141-RealAmp) using six oligonucleotide primers derived from cyp141 to detect MTB. A combined number of 213 sputum samples (169 obtained from clinically diagnosed cases of pulmonary TB and 44 from a control group without tuberculosis) underwent Acid-fast bacillus (AFB) smear, culture, Xpert MTB/RIF assays, and cyp141-RealAmp assay. ResultsBy targeting MTB cyp141, this technique could detect as low as 10 copies/reaction within 30 min, and it was successfully rejected by other mycobacteria and other bacterial species tested. Of the 169 patients, there was no statistical difference between the detection rate of cyp141-RealAmp (92.90%, 95% CI: 89.03–96.07) and that of Xpert MTB/RIF (94.67%, 95% CI: 91.28–98.06) (P &gt; 0.05), but both were statistically higher than that of culture (65.68%, 95% CI: 58.52–72.84) (P&lt; 0.05) and AFB (57.40%, 95% CI: 49.94–64.86) (P&lt; 0.05). Both cyp141-RealAmp and Xpert MTB/RIF had a specificity of 100%. Furthermore, a high concordance between cyp141-RealAmp and Xpert MTB/RIF was found (Kappa = 0.89).ConclusionThe cyp141-RealAmp assay was shown to be effective, responsive, and accurate in this study. This method offers a prospective strategy for the speedy and precise detection of MTB

Evaluation of an identification method for the SARS-CoV-2 Delta variant based on the amplification-refractory mutation system

The Delta variant of SARS-CoV-2 dominated the COVID-19 pandemic due to its high viral replication capacity and immune evasion, causing massive outbreaks of cases, hospitalizations, and deaths. Currently, variant identification is performed mainly by sequencing. However, the high requirements for equipment and operators as well as its high cost have limited its application in underdeveloped regions. To achieve an economical and rapid method of variant identification suitable for undeveloped areas, we applied an amplification-refractory mutation system (ARMS) based on PCR for the detection of novel coronavirus variants. The results showed that this method could be finished in 90 min and detect as few as 500 copies/mL and not react with SARS-Coronavirus, influenza A H1N1(2009), and other cross-pathogens or be influenced by fresh human blood, α- interferon, and other interfering substances. In a set of double-blind trials, tests of 262 samples obtained from patients confirmed with Delta variant infection revealed that our method was able to accurately identify the Delta variant with high sensitivity and specificity. In conclusion, the ARMS-PCR method applied in Delta variant identification is rapid, sensitive, specific, economical, and suitable for undeveloped areas. In our future study, ARMS-PCR will be further applied in the identification of other variants, such as Omicron

GWAS Analysis and QTL Identification of Fiber Quality Traits and Yield Components in Upland Cotton Using Enriched High-Density SNP Markers

It is of great importance to identify quantitative trait loci (QTL) controlling fiber quality traits and yield components for future marker-assisted selection (MAS) and candidate gene function identifications. In this study, two kinds of traits in 231 F6:8 recombinant inbred lines (RILs), derived from an intraspecific cross between Xinluzao24, a cultivar with elite fiber quality, and Lumianyan28, a cultivar with wide adaptability and high yield potential, were measured in nine environments. This RIL population was genotyped by 122 SSR and 4729 SNP markers, which were also used to construct the genetic map. The map covered 2477.99 cM of hirsutum genome, with an average marker interval of 0.51 cM between adjacent markers. As a result, a total of 134 QTLs for fiber quality traits and 122 QTLs for yield components were detected, with 2.18–24.45 and 1.68–28.27% proportions of the phenotypic variance explained by each QTL, respectively. Among these QTLs, 57 were detected in at least two environments, named stable QTLs. A total of 209 and 139 quantitative trait nucleotides (QTNs) were associated with fiber quality traits and yield components by four multilocus genome-wide association studies methods, respectively. Among these QTNs, 74 were detected by at least two algorithms or in two environments. The candidate genes harbored by 57 stable QTLs were compared with the ones associated with QTN, and 35 common candidate genes were found. Among these common candidate genes, four were possibly “pleiotropic.” This study provided important information for MAS and candidate gene functional studies

ALGEBRAICALLY EXPLICIT ANALYTICAL SOLUTIONS OF UNSTEADY CONDUCTION WITH VARIABLE THERMAL PROPERTIES IN SPHEROIDAL COORDINATES

Abstract The analytical solutions of unsteady heat conduction with variable thermal properties (thermal conductivity, density and specific heat are functions of temperature or coordinates) are meaningful in theory. In addition, they are very useful to the computational heat conduction to check the numerical solutions and to develop numerical schemes, grid generation methods and so forth. Such solutions in rectangular coordinates have been derived by the authors; some other solutions for unsteady point symmetrical heat conduction in spherical coordinates are given in this paper to promote the heat conduction theory and to develop the * Corresponding author: Tel. +86-10-62561887; Fax. +86-10-62575913 ; Email. [email protected] relative computational heat conduction