A novel catalyst, polyoxometallate-stabilized platinum–ruthenium alloy nanoparticles supported on multiwalled carbon nanotubes (Pt–Ru–PMo
12-MWNTs), was synthesized by a microwave-assisted polyol ...process. The effects of microwave reaction time, microwave reaction power, and pH value of the reaction solution on the electrocatalytic properties of Pt–Ru–PMo
12-MWNTs catalysts were also investigated. The polyoxometallate (PMo
12) formed a self-assembled monolayer on the surface of the Pt/Ru nanoparticles and MWNTs, which effectively prevented the agglomeration of Pt, Ru nanoparticles and MWNTs, due to the electrostatic repulsive interactions between the negatively charged PMo
12 monolayers. Energy dispersive spectroscopy examination and electrochemical measurements showed that the loading content of Pt/Ru and their electrochemical activity vary with the synthesis conditions, such as pH, reaction time, and microwave power. It was found that the a Pt–Ru–PMo
12-MWNTs electrocatalyst with high Pt loading content, small crystallite size, and good electrocatalytic activity could be synthesized using a long reaction time, intermediate microwave power, and a pH value of 7. The electrocatalysts obtained were characterized using X-ray diffraction, and scanning and transmission electron microscopy. Their electrocatalytic properties were also investigated by using the cyclic voltammetry technique.
The distributions of residual strains and grain boundary microstructures were investigated in the heat-affected zone (HAZ) of a weld joint between Alloy 690TT (thermally treated) and Alloy 52 using ...electron backscatter diffraction (EBSD) and transmission electron microscopy. The distributions of residual strains were examined at the top, middle, and root of the HAZ using EBSD to obtain the grain average misorientation. The weld residual strain increased from the top of the weld to the root while the peak of strain approached the fusion boundary (FB) in the HAZ. The maximum strains and their distances to the FB in the top, middle, and root was 15% and 800
μm, 17% and 600
μm, 20% and 200
μm, respectively. The fraction of Σ3 special boundaries was about 40% in the HAZ but with obvious deviations from the structure of ideal boundaries. The HAZ region is considered to sustain the highest susceptibility to SCC at the root of the weld.
We present a search for the lepton flavor violating decay
J
/
ψ
→
e
±
μ
∓
using 8.998 × 10
9
J
/
ψ
events collected with the BESIII detector at the BEPCII
e
+
e
−
storage ring. No excess of signal ...above background is observed; we therefore set an upper limit on the branching fraction of
ℬ
(
J
/
ψ
→
e
±
μ
∓
)
<
4.5
×
10
−
9
at the 90% confidence level. Improving the previous best result by a factor of more than 30, this measurement places the most stringent limit to date on lepton flavor violation in the heavy quarkonium sector.
Although the Kyoto Protocol does not require commitments from developing countries, carbon inventories are essential and required for further assessing the potential roles developing countries can ...play in mitigating the accumulation of CO
2 in the atmosphere. Here we present estimates of terrestrial carbon pools as soil organic carbon and carbonate carbon in soils of China by using inventory data from the National Soil Resource Survey and Chinese Academy of Sciences. The total soil organic carbon and carbonate carbon in soils of China for a depth of 100 cm were estimated to be 83.8 Pg and 77.9 Pg C, respectively, and for whole soil profile was estimated to be 147.9 Pg and 234.2 Pg, respectively, with the sum of overall carbon storage 382.1 Pg. Terrestrial soil carbon storage and density (both organic carbon and carbonate carbon) in soils of China vary with and are modulated by bioclimatic conditions (temperature and precipitation/evaporation). The temperate regions have sequestered more terrestrial carbon in soils than the tropical and subtropical regions. This study suggests that terrestrial carbon in China is mainly sequestered in soil pool instead of aboveground forest biomass. Management practices of soils of China to stabilize and reduce carbon release from soil will play an important role in global carbon cycles.
The mechanisms of influenza A virus mRNA intracellular transport are still not clearly understood. Here, we visualized the distribution and transport of influenza A virus mRNA in living cells using ...molecular beacon (MB) technology. Confocal-FRAP measurements determined that the transport of influenza A virus intronless mRNA, in both nucleus and cytoplasm, was energy dependent, being similar to that of Poly(A)+ RNA. Drug inhibition studies in living cells revealed that the export of influenza A virus mRNA is independent of the CRM1 pathway, while the function of RNA polymerase II (RNAP-II) may be needed. In addition, viral NS1 protein and cellular TAP protein were found associated with influenza A virus mRNA in the cell nucleus. These findings characterize influenza A virus mRNA transport in living cells and suggest that influenza A virus mRNA may be exported from the nucleus by the cellular TAP/p15 pathway with NS1 protein and RNAP-II participation.
Graphical abstract Highlights ► IMM-H004 exhibits significant protection against Aβ-induced apoptosis. ► IMM-H004 reverses the damage of mitochondria. ► IMM-H004 protects neurons through a ...caspase-dependent pathway. ► IMM-H004 protects neurons also by the AIF-dependent pathway. ► IMM-H004 is a potential compound to therapy AD-like degeneration.
We investigated the light reactions, CO₂ assimilation, but also the chloroplast ultrastructure in the upper three functional leaves (flag, 2ⁿᵈ, and 3ʳᵈ leaves) of the Chinese super-high-yield hybrid ...rice (Oryza sativa L.) Liangyoupeijiu (LYPJ) with ultraviolet-B (UV-B) treatment during reproductive development. Photosynthetic parameters showed that the upper 3 functional leaves of LYPJ entered into senescence approximately 15 days after flag leaf emergence (DAE). Leaves in UV-B treatment exhibited greater efficiency in absorbing and utilizing light energy of photosystem II (PSII), characterized by higher chlorophyll (Chl) content and the whole chain electron transport rate (ETR). However, UV-B radiation reduced activities of Ca²⁺-ATPase and photophosphorylation. The significantly decreased activity of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) was greatly associated with the decline in photosynthetic efficiency. The net photosynthetic rate (P N) and stomatal conductance (g ₛ) suffered strong reductions before 25 DAE, and afterwards showed no significant difference between control and treatment. UV-B treatment delayed chloroplasts development of flag leaves. Chloroplast membranes later swelled and disintegrated, and more stromal thylakoids were parallel to each other and were arranged in neat rows, which might be responsible for better performance of the primary light reaction. It is likely that accumulation of starch and an increase in the number of lipid droplet and translucent plastoglobuli were results of an inhibition of carbohydrate transport. Our results suggest that long-term exposure to enhanced UV-B radiation was unlikely to have detrimental effects on the absorption flux of photons and the transport of electrons, but it resulted in the decrease of photophosphorylation and Rubisco activation of LYPJ. The extent of the damage to the chloroplast ultrastructure was consistent with the degree of the inhibition of photosynthesis.
The effect of vanadium (V) addition on the microstructure, the hardness and the electrical conductivity of Cu-2.8Ni-0.7Si alloys was investigated. The V-free, the 0.1 wt% V-added, the 0.2 wt% V-added ...Cu base alloys were exposed to the same experimental conditions. After the cold rolling of the studied alloys, the matrix was recrystallized during the solution heat treatment at 950 °C for 2 h. However, small amounts of vanadium substantially suppressed the recrystallization and retarded the grain growth of the Cu base alloys. The added vanadium accelerated the precipitation of Ni
2
Si intermetallic compounds during aging and therefore it contributed positively to the resultant hardness and electrical conductivity. It was found that the hardness and the electrical conductivity increased simultaneously with increasing aging temperature and time with accelerated precipitation kinetics by the addition of vanadium. In the present study, the Cu-2.8Ni-0.7Si alloy with 0.1 wt%V was found to have an excellent combination of the hardness and the electrical conductivity when it was aged at 500 °C.
To observe the effect of modified micro titanium plate for extensor attachment point reconstruction in open-door laminoplasty.
From January 2016 to February 2017, 26 patients with cervical ...spondylotic myelopathy underwent open-door laminoplasty+modified micro-titanium plate fixation+extensor muscle attachment point reconstruction at Tianjin Hospital were enrolled in this study. There were 14 males and 12 females in this group, aged (59±18) years. The improvement of neurological function based on the Japanese Orthopedic Association (JOA) score and the changes cervical curvature based on the cervical curvature index (CCI), especially the atrophy of the back muscles and the occurrence axial symptoms were recorded and analyzed. Intra-group comparisons were performed by using repeated measures of variance analysis or paired
-test.
The operations were performed well without injury to spinal cord. The operation time was (116±32) min with a blood loss of (196±41) ml. The JOA scores was improved form 7.8±2.1 preoperat
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