An electrocatalytic methanol oxidation reaction (MOR) is proposed to replace oxygen evolution reaction (OER) in water electrolysis owing to the favorable thermodynamics of MOR than OER. However, ...there is still a competition between the MOR and the OER when the applied potential is in the conventional OER zone. How to inhibit OER while maintaining efficient MOR is an open and challenging question, and there are few reports focusing on this thus far. Herein, by taking NiFe layered double hydroxide (LDH) as a model catalyst due to its intrinsically high catalytic activity for the OER, the perspective of inhibiting OER is shown and thus promoting MOR through a heterogenous engineering of NiFe‐LDH. The engineered heterostructure comprising NiFe‐LDH and in situ formed NiFe‐hexylaminobenzene (NiFe‐HAB) coordination polymer exhibits outstanding electrocatalytic capability for methanol oxidation to formic acid (e.g., the Faradaic efficiencies (FEs) of formate product are close to 100% at various current densities, all of which are much larger than those (53–65%) on unmodified NiFe‐LDH). Mechanism studies unlock the modification of NiFe‐HAB passivates the OER activity of NiFe‐LDH through tailoring the free energies for element reaction steps of the OER and increasing the free energy of the rate‐determining step, consequently leading to efficient MOR.
The engineered novel heterostructure comprising NiFe‐LDH and in situ formed NiFe‐hexylaminobenzene (NiFe‐HAB) coordination polymer exhibits outstanding electrocatalytic capability for methanol oxidation to formic acid. Mechanism studies unlock the modification of NiFe‐HAB passivates the OER activity of NiFe‐LDH through tailoring the free energies for element reaction steps of the OER and increasing the free energy of the rate‐determining step.
Developing electrocatalysts that exhibit both high activity and ammonia selectivity for nitrate reduction is a significant and demanding challenge, primarily due to the complex nature of the ...multiple-electron reduction process involved. An encouraging approach involves coupling highly active precious metals with transition metals to enhance catalytic performance through synergy. Here, we report a ruthenium-nickel alloy catalyst with nanosheets (Ru-Ni NSs) structure that achieves a remarkable ammonia Faradaic efficiency of approximately 95.93%, alongside a yield rate of up to 6.11 g·h
−1
·cm
−2
. Moreover, the prepared Ru-Ni NSs exhibit exceptional stability during continuous nitrate reduction in a flow reactor for 100 h, maintaining a Faradaic efficiency of approximately 90% and an ammonia yield of 37.4 mg·L
−1
·h
−1
using 0.05 M nitrate alkaline electrolyte. Mechanistic studies reveal that the catalytic process follows a two-step pathway, in which HONO serves as a migration intermediate. The presence of a partially oxidized Ru (002) surface enhances the adsorption of nitrate and facilitates the release of the migration intermediate by adjusting the strength of the electrostatic and covalent interactions between the adsorbate and the surface, respectively. On the other hand, the Ni (111) surface promotes the utilization of the migration intermediate and requires less energy for NH
3
desorption. This tandem process contributes to a high catalytic activity of Ru-Ni NSs towards nitrate reduction.
Background
The Himalayan marmot (Marmota himalayana) plays a reservoir role in the epidemiology of brucellosis. However, the changes in blood biochemical parameters are still unclear in ...Brucella‐seropositive marmots.
Objectives
The present study was designed to explore the hematologic and biochemical variable changes in Brucella‐seropositive marmots.
Methods
Blood samples were collected from the dorsalis pedis vein of Himalayan marmots (24 Brucella‐seropositive marmots and 24 Brucella‐free marmots). Ten hematologic and 10 serum biochemical variable examinations were performed and analyzed.
Results
Our results showed that leukocyte, platelet, neutrophil, and lymphocyte counts significantly increased, while the level of carbon dioxide combining power decreased in Brucella‐infected marmots. These findings indicate that Brucella triggers an immune response in Himalayan marmots.
Conclusions
This study provides a preliminary investigation of the changes in blood biochemical analytes in Brucella‐infected marmots. The interaction between Brucella infection and blood biochemical indices in Himalayan marmots should be further explored.
A novel proton conductor was synthesized by intercalation of phosphotungstic acid (PWA) into layered ferric sulfophenyl phosphate (FeSPP) via in-situ polymerization. Fe-O-W covalent bonds were formed ...between FeSPP and PWA in the synthesized intercalated proton conductor (FeSPP-PWA). FeSPP-PWA with a PWA content of up to 42 wt% remained the layered structure of FeSPP. FeSPP-PWA exhibited good thermal stability up to 200 °C. The ion-exchange capacity of FeSPP-PWA(15 wt%) was 1.73 meq g−1. Its proton conductivity was 0.14, 6.6 × 10−2 and 1.65 × 10−2 S cm−1 at 100%, 50% and 0 RH at 180 °C, respectively, corresponding to the activation energy of 15.2, 17.3 and 27.0 kJ mol−1, respectively. After washing for 12 and 24h, the conductivity of FeSPP-PWA(15 wt%) at 180 °C at 100% RH reduced by 1.5% and 1.7%, respectively. In comparison, the proton conductor prepared by direct mixing of FeSPP and PWA showed lower proton conductivity and poorer washing fastness than FeSPP-PWA. Intercalation of PWA into FeSPP proved to be an effective method for the preparation of high performance proton conductor.
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•PWA was intercalated into FeSPP to prepare novel high temperature proton conductor.•The Fe-O-W covalent bonds formed blocked leaching and ensured hydrolysis stability.•Better washing fastness was achieved by in-situ polymerization than direct mixing.•Good conductivity was obtained at high temperature and various relative humidity.
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•Zirconium phytate (ZrP) was prepared as a novel inorganic-organic proton conductor.•Tuning Zr/P molar ratio enhanced the proton conductivity and avoids acid leaching.•ZrPA(3:4) ...exhibited an ion exchange capacity of 1.04meq/g at room temperature.•High proton conductivity at high temperature and different humidity were achieved.
Zirconium phytate (ZrPA) was prepared via gelation of zirconyl chloride and phytic acid in certain ratios. Fourier-transform infrared spectroscopy was applied to confirm the structure and interactions between Zr4+ and phytate ions, including hydrogen bonding and chelation. Scanning and transmission electron microscopic study have shown that ZrPA has a fusiform shape and a layered structure. Good thermal stability up to 250°C was obtained. ZrPA(3:4) exhibited an ion exchange capacity of 1.04meqg−1. At 140°C, the proton conductivity of ZrPA(3:4) was 0.099Scm−1 at 100% RH, 0.042Scm−1 at 50% RH and 0.018Scm−1 at 0RH.
SiO
2
-riveted phosphotungstic acid (T–PWA–SiO
2
) was synthesized using the sol–gel method and thermally treated in a microwave synthesizer. The dissolving-detaching experiment shows that PWA in ...T–PWA–SiO
2
exhibits better fastness than in the sample without thermal treatment (PWA–SiO
2
). The T–PWA–SiO
2
samples were then combined with poly(2,5-benzimidazole) (ABPBI) to prepare ABPBI/(T–PWA–SiO
2
) composite membranes using the polyphosphoric acid direct-casting method. These composite membranes were characterized through X-ray diffraction and infrared spectroscopy. Then, the T–PWA–SiO
2
particles were combined with ABPBI through hydrogen bonding between PWA and C=N in ABPBI. Membrane morphologies were investigated using scanning electron microscopy. Results of the thermogravimetric analysis indicate thermal stability of the composite membranes below 200 °C. The proton conductivity and durability between ABPBI/(T–PWA–SiO
2
) and ABPBI/(PWA–SiO
2
) composite membranes were also compared. The conductivity and life of the composite membranes were enhanced using T–PWA–SiO
2
. The conductivity of the ABPBI/(T–PWA–SiO
2
) (46 wt%) composite membrane was approximately 0.055 S/cm at 180 °C under 100% relative humidity.
Indium-based materials (e.g., In
2
O
3
) are a class of promising non-noble metal-based catalysts for electroreduction of carbon dioxide (CO
2
). However, competitive hydrogen reduction reaction ...(HER) on indium-based catalysts hampers CO
2
reduction reaction (CO
2
RR) process. We herein tune the interfacial microenvironment of In
2
O
3
through chemical graft of alkyl phosphoric acid molecules using a facile solution-processed strategy for the first time, which is distinguished from other researches that tailor intrinsic activity of In
2
O
3
themselves. The surface functionalization of alkyl phosphoric acids over In
2
O
3
is demonstrated to remarkably boost CO
2
conversion. For example, octadecylphosphonic acid modified In
2
O
3
exhibits Faraday efficiency for H
2
(
FE
H
2
) of as low as 6.6% and FE
HCOOH
of 86.5% at −0.67 V vs. RHE, which are far superior to parent In
2
O
3
counterparts (
FE
H
2
of 24.0% and FE
HCOOH
of 63.1%). Moreover, the enhancing effect of alkyl phosphoric acid functionalization is found to be closely related to the length of alkyl chains. By virtue of comprehensive experimental characterizations and molecular dynamics simulations, it is revealed that the modification of alkyl phosphoric acids significantly alters the interface microenvironment of the electrocatalyst, which changes the electrocatalyst surface from hydrophilic and aerophobic to hydrophobic and aerophilic. In this case, the water molecules are pushed away and more CO
2
molecules are trapped, increasing local CO
2
concentration at In
2
O
3
active sites, thus leading to the significantly enhanced CO
2
RR and suppressed HER. This work highlights the importance of regulating the interfacial microenvironment of inorganic catalysts by molecular surface functionalization as a means for promoting the electrochemical performance in electrosynthesis and beyond.
Ultra-high sensitivity temperature sensing and stable thermal control are crucial for many science experiments testing fundamental theories to high precision. Here we report the first pico-kevin ...scale thermometer operating at room temperature with an exceptionally low theoretical noise figure of ~70pK/Hz at 1 Hz and a high dynamic range of ~500 K. We have experimentally demonstrated a temperature sensitivity of <3.8nK/Hz at 1 Hz near room temperature, which is an order of magnitude improvement over the state of the art. We have also demonstrated an ultra-high stability thermal control system using this thermometer, achieving 3.7 nK stability at 1 s and ∼ 120 pK at 10
s, which is 10-100 times more stable than the state of the art. With some upgrades to this proof-of-principle device, we can expect it to be used for very high resolution tests of special relativity and in critical point phenomena.
In this study, we explored the influence of single nucleotide polymorphism (SNP) in the noncoding region of intercellular adhesion molecule 1 (ICAM1) gene on the occurrence and metastasis of primary ...hepatocellular carcinoma (PHC).
Sanger sequencing was used to analyze the genotypes of rs3093032, rs923366, and rs281437 locus in the 3'untranslated region (UTR) of the
gene. The level of plasma ICAM1 was analyzed by enzyme-linked immunosorbent assay (ELISA).
After adjusting for risk factors such as BMI, smoking, drinking, family history of tumors, and hepatitis B virus test results, the CT genotype at rs3093032 of the
gene (OR = 0.19, 95% CI: 0.08-0.44,
< 0.01), dominance model (OR = 0.23, 95% CI: 0.11-0.48,
< 0.01), and T allele (OR = 0.27, 95% CI: 0.14-0.53,
< 0.01) were related to the reduced risk of PHC susceptibility. rs923366 locus CT genotype (OR = 0.63, 95% CI: 0.44-0.90,
= 0.01), TT genotype (OR = 0.23, 95% CI: 0.10-0.53,
< 0.01), dominant model (OR = 0.55, 95% CI: 0.39-0.77,
< 0.01), recessive model (OR = 0.28, 95% CI: 0.12-0.62,
< 0.01), and T allele (OR = 0.55, 95% CI: 0.42-0.73,
< 0.01) were related to a reduction in the risk of PHC susceptibility. rs281437 locus CT genotype (OR = 2.08, 95% CI: 1.40-3.09,
< 0.01), TT genotype (OR = 5.20, 95% CI: 2.22-12.17,
< 0.01), dominant model (OR = 2.45, 95% CI: 1.69-3.54,
< 0.01), recessive model (OR = 4.32, 95% CI: 1.86-10.06,
< 0.01), and T allele (OR = 2.46, 95% CI: 1.79-3.38,
< 0.01) were significantly related to the increased risk of PHC susceptibility. SNPs at rs3093032, rs923366, and rs281437 of the
gene were significantly correlated with TNM stage and tumor metastasis of PHC patients (
< 0.05).
SNPs at rs3093032, rs923366, and rs281437 in the 3'UTR region of the
gene are related to the occurrence and metastasis of PHC.
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