A globally accurate many-body expansion potential energy surface is reported for HCS(X
A') by fitting a wealth of accurate ab initio energies calculated at the multireference configuration ...interaction level using aug-cc-pVQZ and aug-cc-pV5Z basis sets via extrapolation to the complete basis set limit. The topographical features of the present potential energy surface are examined in detail and is in good agreement with the raw ab initio results, as well as other theoretical results available in literatures. By utilizing the potential energy surface of HCS(X
A'), the dynamic studies of the C(
P) + SH(X
Π) → H(
S) + CS(X
∑
) reaction has been carried out using quasi-classical trajectory method.
A kind of coordination polymer nanoparticles was facily prepared using Fe(II) and GMP as the motifs through a coordination-driven self-assembly process. The resultant Fe-GMP CPNs show excellent ...peroxidase-like activity via the conversion of H2O2 into OH, accompanied by high antibacterial efficiency. GOX could be adaptively encapsulated into Fe-GMP CPNs, and the proposed GOX@Fe-GMP CPNs functioned as an enzyme cascade model with a glucose-responsive property in OH production, with excellent antibacterial and wound disinfection efficiency under physiological conditions.
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•Self-assemblied coordination polymer nanoparticles were prepared using Fe(II) and GMP.•The Fe-GMP CPNs show excellent peroxidase-like activity through OH production.•The Fe-GMP CPNs indicated high antibacterial efficiency for E. coli and S. aureus.•The prepared GOX@Fe-GMP CPNs functioned as an enzyme cascade model in OH production.•GOX@Fe-GMP CPNs have excellent antibacterial and wound disinfection efficiency.
The intelligent regulation of reactive oxygen species by nanozymes and the corresponding cascade catalysis hold great potential as a promising next-generation therapeutic methodology. However, the preparation of nanozymes usually involves high material consumption and tedious multistep processes, especially during the packaging of several functional components to realize the enzyme cascade. Here, we propose a facile strategy to prepare the coordination polymer nanoparticles (CPNs) using ferrous ions as the iron source and guanosine monophosphate (GMP) as the supramolecular motif. The resultant Fe-GMP CPNs show excellent peroxidase-like activity via the conversion of H2O2 into highly active OH, accompanied by high antibacterial efficiency, as well as high encapsulation capacity to simultaneously immobilize guest components through an adaptive self-assembly process. Typically, glucose oxidase (GOX) encapsulation endows as-prepared GOX@Fe-GMP CPNs with glucose-responsive properties, so that glucose can be ultimately converted into OH via intermediate H2O2. This convenient cascade catalysis system not only possesses excellent antibacterial efficiencies, inhibiting the growth of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) by 99% and significantly promoting wound healing in the absence of additional H2O2, but also has great application potential in the fields of biocatalysis and biomedicine.
Extracellular elastin-derived peptides (EDPs) accumulate in the aging brain and have been associated with vascular dementia and Alzheimer's disease (AD). The activation of inflammatory processes in ...glial cells with EDP treatment has received attention, but not in neurons. To properly understand EDPs' pathogenic significance, the impact on neuronal function and neuron-microglia crosstalk was explored further. Among the EDP molecules, Val-Gly-Val-Ala-Pro-Gly (VGVAPG) is a typical repeating hexapeptide. Here, we observed that EDPs-VGVAPG influenced neuronal survival and morphology in a dose-dependent manner. High concentrations of VGVAPG induced synapse loss and microglia hyperactivation in vivo and in vitro. Following EDP incubation, galectin 3 (Gal-3) released by neurons served as a chemokine, attracting microglial engulfment. Blocking Gal-3 and EDP binding remedied synapse loss in neurons and phagocytosis in microglia. In response to the accumulation of EDPs, proteomics in matrix remodeling and cytoskeleton dynamics, such as a disintegrin and metalloproteinase (ADAM) family, were engaged. These findings in extracellular EDPs provided more evidence for the relationship between aging and neuron dysfunction, increasing the insight of neuroinflammatory responses and the development of new specialized extracellular matrix remolding-targeted therapy options for dementia or other neurodegenerative disease.
The quasi-classical trajectory calculations are carried out to investigate the isotopic substitution effect on title reactions based on the recently developed, accurate potential energy surface of ...the HCS(X
2
A
′
) (Song, Zhang, et al. Sci. Rep.
6
, 37734 (2016)). The total integral cross sections (ICSs) and vibrational state resolved ICSs are obtained for C + SH(D, T) → H(D, T) + CS reactions. In addition, differential cross sections and two angle distribution functions P(θ
r
), P(
ϕ
r
) at different collision energies are investigated. It is found that the peaks of P(θ
r
) and P(
ϕ
r
) become lower with the reagent molecule SH turning into SD and ST.
In this article, a novel snapback-free reverse-conducting insulated-gate bipolar transistor (RC-IGBT) with P+ pillars at the collector side (PPC) is proposed and investigated by TCAD simulations. ...This structure features the P+ pillar structure at the side of collector and exits a gap of N-buffers above N+ collector. The P+ pillars increase the distributed resistance below the buffer layer during turn-on transient, show bipolar mode, and eliminate the snapback phenomenon. Accordingly, the structure eliminates the snapback phenomenon with a smaller half-cell pitch of <inline-formula> <tex-math notation="LaTeX">{10}~\mu \text{m} </tex-math></inline-formula>, making that the device is more reliable and suitable for parallel connection. For the same forward voltage drop, the turn-off loss of the PPC structure is reduced by 34%.
In this paper, a SiC LDMOS with double L-shaped buried oxide layers (DL-SiC LDMOS) is investigated and simulated. The DL-SiC LDMOS consists of two L-shaped buried oxide layers and two SiC windows. ...Using 2-D numerical simulation software, Atlas, Silvaco TCAD, the breakdown voltage, and the self-heating effect are discussed. The double-L shaped buried oxide layers and SiC windows in the active area can introduce an additional electric field peak and make the electric field distribution more uniform in the drift region. In addition, the SiC windows, which connect the active area to the substrate, can facilitate heat dissipation and reduce the maximum lattice temperature of the device. Compared with the BODS structure, the DL-SiC LDMOS and BODS structures have the same device parameters, except of the buried oxide layers. The simulation results of DL-SiC LDMOS exhibits outstanding characteristics including an increase of the breakdown voltage by 32.6% to 1220 V, and a low maximum lattice temperature (535 K) at room temperature.
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•SiC LDMOS with double L-shaped buried oxide layers (DL-SiC LDMOS) is investigated and simulated.•DL-SiC LDMOS can improve breakdown voltage and prevent self-heating effect combining the technology of ENDIF and P-SOI.•The breakdown voltage of proposed LDMOS is increased 32.6% and maximum lattice temperature is reduced 24 K.
In this paper, we propose a SiC LDMOS structure with a step compound drift region (SC-LDMOS). The proposed device has a compound drift region which consists of an n-type top layer, a step p-type ...middle layer and an n-type bottom layer. The step p-type middle layer can introduce two new electric field peaks and uniform the distribution of the electric field in the n-type top layer, which can modulate the surface electric field and improve the breakdown voltage of the proposed structure. In addition, the n-type bottom layer is applied under the heavy doping p-type middle layer，which contributes to realize the charge balance. Furthermore, it can also increase the doping concentration of the n-type top layer, which can decrease the on resistance of the proposed device. As a simulated result, the proposed device obtain a high BV of 976 V and a low Rsp,on of 7.74 mΩ·cm2. Compared with the conventional single REUSRF LDMOS and triple RESURF LDMOS, BV of proposed device is enhanced by 42.5% and 14.7%, respectively and Rsp,on is reduced by 37.3% and 30.9%, respectively. Meanwhile, the switching delays of the proposed device are significantly shorter than the conventional triple RESURF LDMOS.
•SiC LDMOS with a step compound drift region (SC-LDMOS) is investigated and simulated.•SC-LDMOS can improve breakdown voltage and reduce specific on-resistance combining the technology of multiple RESURF and varied lateral thickness.•The switching delays of turn-on and turn-off for the proposed SC-LDMOS are much shorter than the TR-LDMOS.
Three Ag(I) coordination complexes, namely Ag
3
(2-stp)(2-apy)
2
·3H
2
O
n
(
1
), Ag
3
(2-stp)(2-apy)
2
n
(
2
) and Ag
3
(2-stp)(3-apy)(H
2
O)
n
(
3
) (2-NaH
2
stp = 2-sulfoterephthalic acid ...monosodium salt, 2-apy = 2-aminopyridine and 3-apy = 3-aminopyridine), have been synthesized and structurally characterized. They all show two-dimensional network structures. In complex
1
, the Ag
3
units are linked by stp ligands to form a 1D chain. Consequently, the 2-apy ligands link the adjacent 1D chain into 2D polymeric sheets. In
2
, Ag1 and Ag2 atoms are bridged by stp ligands to form a 2D infinite sheet. In
3
, the stp anion adopts a μ
7
-(η
1
,η
2
):(η
1
,η
1
,η
0
):(η
1
,η
1
) coordination mode to Ag
3
units to 2D layer sheet and the network is consolidated by 3-apy ligands. The thermogravimetric analyses and photoluminescence of the complexes were also investigated.
A globally accurate potential energy surface is reported for the electronic ground-state HLi
2
by fitting ab initio energies to double many-body expansion formalism. The total 3726 ab initio energies ...used to map the HLi
2
potential energy surface are calculated using the multi-reference configuration interaction method, with their dynamical correlation being semiempirically corrected by the double many-body expansion-scaled external correlation method. The current potential energy surface generates an excellent fit of the ab initio energies, showing a small root-mean squared derivation of 0.636 kcal mol
-1
. The topographical features of the HLi
2
potential energy surface are examined in detail, which concludes that the H + Li
2
(
X
1
Σ
g
) → Li + LiH(
X
1
Σ
) reaction is essentially barrierless and the exothermicity is calculated to be 33.668 kcal mol
-1
, thus corroborates the available experimental and theoretical results.
Sargassum is one of the most important economic algae in Phaeophyta. It has broad prospects for development and application in industry, agriculture, food, medicine and ecological restoration, and ...plays an important role in maintaining the marine ecosystem. In recent years, however, environmental degradation, offshore farming and overharvesting have changed the ecosystem structure and threatened the Sargassum resources. To understand the composition and characteristics of Sargassum in Hainan, we conducted an annual field survey of four bays around Hainan Island, including Haiwei, Qinglan, Lingshui and Sanya. Results indicated that 16 species of Sargassum were collected in the intertidal zone of Hainan Island, belonging to two subgenera, three sections, and S. polycystum was the dominant species at all stations throughout the year. Lingshui and Sanya had the highest biodiversity index, followed by Qinglan and Haiwei. The community similarity between Qinglan and Lingshui was the highest, followed by Haiwei and Sanya. The biodiversity index of Sargassum was the highest in summer, followed by late spring and autumn, and the lowest in winter.
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