To understand the effect of the doping amount of Cu2+ on the structure and reactivity of SnO2 in NOx-SCR with NH3, a series of Sn-Cu-O binary oxide catalysts with different Sn/Cu ratios have been ...prepared and thoroughly characterized. Using the XRD extrapolation method, the SnO2 lattice capacity for Cu2+ cations is determined at 0.10 g CuO per g of SnO2, equaling a Sn/Cu molar ratio of 84/16. Therefore, in a tetragonal rutile SnO2 lattice, only a maximum of 16% of the Sn4+ cations can be replaced by Cu2+ to form a stable solid solution structure. If the Cu content is higher, CuO will form on the catalyst surface, which has a negative effect on the reaction performance. For samples in a pure solid solution phase, the number of surface defects increase with increasing Cu content until it reaches the lattice capacity, as confirmed by Raman spectroscopy. As a result, the amounts of both active oxygen species and acidic sites on the surface, which critically determine the reaction performance, also increase and reach the maximum level for the catalyst with a Cu content close to the lattice capacity. A distinct lattice capacity threshold effect on the structure and reactivity of Sn-Cu binary oxide catalysts has been observed. A Sn-Cu catalyst with the best reaction performance can be obtained by doping the SnO2 matrix with the lattice capacity amount of Cu2+.
Doping the SnO2 matrix with the lattice capacity amount of Cu2+ gives an optimal Sn–Cu catalyst for NOx-SCR with NH3 by maximizing surface active oxygen and acidic sites.
Abstract
The influence of sintering parameters on the microstructure, phase composition and mechanical property of the Ti
3
SiC
2
/Cu composites sintered by spark plasma sintering technique was ...investigated and the related sintering mechanism was clarified in detail. Results indicated that during the heating process, one part of the high energy adsorbed by the composites let Cu melt and fill the gaps inside the composites. Meanwhile, there’s different molten condition about Cu duel to different heating temperature that cause Cu fill in the most space between Ti
3
SiC
2
particles. The other part of the energy caused to the local high temperature, contributing for the chemical reaction and the formation of TiC
x
and Cu
3
Si. Therefore, at the same heating rate, the composites showed better mechanical property and higher density with a longer heating time. The heating stage played an important role in the change of the mechanical property, microstructure and volume of the composites. During the holding stage, because the amount of the reactants significantly decreased, the related chemical reaction got slow and the energy needed during this stage was lower than that during the heating stage. And the particle of Ti
3
SiC
2
need more time for moving to the space of Cu. Therefore, the higher the holding temperature, the more significant was the diffusion of the phases. The more uniform the phases, the higher was the density. When heating temperature (higher than holding temperature) cause Cu complete melt and holding temperature keep the Cu in semi-melt, there will be a more effective sintering method.
•Ghrelin(1–7)-NH2 (i.c.v.) induced antinociception in acute pain in mice.•Ghrelin(1–7)-NH2 induced antinociception through GHS-R1α and opioid receptors.•Ghrelin(1–7)-NH2(i.c.v.) was distributed at ...the dorsal 3rd ventricle and hippocampus.•mRNA and protein levels of δ-opioid peptide and receptor were increased in the test.
Ghrelin(1–7)-NH2 is the active N-terminal hepta-peptide of ghrelin as an agonist at the ghrelin receptor GHS-R1α. The biological functions of ghrelin(1–7)-NH2 have not been well investigated. Therefore in this study, we were interested in exploring the effects and molecular mechanisms of ghrelin(1–7)-NH2 in pain modulation at the supraspinal level using the tail withdrawal test in mice. Intracerebroventricular (i.c.v.) injection of ghrelin(1–7)-NH2 (0.002, 0.02, 0.2 and 2 nmol/kg) induced a dose- and time-related antinociceptive effect. This antinociceptive effect was fully antagonized by co-injection with the GHS-R1α antagonist D-Lys3-GHRP-6, indicating that this effect induced by ghrelin(1–7)-NH2 was mediated through the activation of GHS-R1α. Interestingly, naloxone, β-funaltrexamine, naloxonazine, and naltrindole, but not nor-binaltorphimine, could also antagonize the antinociceptive effect markedly, suggesting that OPRM (primary μ1 subtype) and OPRD were involved in the antinociceptive response induced by ghrelin(1–7)-NH2. Furthermore, the qRT-PCR and Western blot results indicated that both mRNA and protein levels of PENK and OPRD were up-regulated significantly. Using the fluorescence labeling method, our results showed that ghrelin(1–7)-NH2 (i.c.v.) was mainly distributed at the dorsal 3rd ventricle and hippocampus where there are regions with high expressions of ghrelin, GHS-R1α and ORs. All these results indicated that ghrelin(1–7)-NH2 initially activated the GHS-R1α, then activated the OPRM, as well as increased the release of endogenous PENK to activate of OPRD to produce antinociception. These results contributed to understanding the mechanisms of antinociception induced by ghrelin(1–7)-NH2. Furthermore, ghrelin(1–7)-NH2 as the active fragment of ghrelin may be a promising peptide for developing new analgesic drugs.
Arachis monticola (2n = 4x = 40) is the only allotetraploid wild peanut within the Arachis genus and section, with an AABB-type genome of ∼2.7 Gb in size. The AA-type subgenome is derived from ...diploid wild peanut Arachis duranensis, and the BB-type subgenome is derived from diploid wild peanut Arachis ipaensis. A. monticola is regarded either as the direct progenitor of the cultivated peanut or as an introgressive derivative between the cultivated peanut and wild species. The large polyploidy genome structure and enormous nearly identical regions of the genome make the assembly of chromosomal pseudomolecules very challenging. Here we report the first reference quality assembly of the A. monticola genome, using a series of advanced technologies. The final whole genome of A. monticola is ∼2.62 Gb and has a contig N50 and scaffold N50 of 106.66 Kb and 124.92 Mb, respectively. The vast majority (91.83%) of the assembled sequence was anchored onto the 20 pseudo-chromosomes, and 96.07% of assemblies were accurately separated into AA- and BB- subgenomes. We demonstrated efficiency of the current state of the strategy for de novo assembly of the highly complex allotetraploid species, wild peanut (A. monticola), based on whole-genome shotgun sequencing, single molecule real-time sequencing, high-throughput chromosome conformation capture technology, and BioNano optical genome maps. These combined technologies produced reference-quality genome of the allotetraploid wild peanut, which is valuable for understanding the peanut domestication and evolution within the Arachis genus and among legume crops.
Frictional behavior of carbide-derived carbon (CDC) coatings on SiC was modified by using MoS3 as solid lubricants in two forms, i.e. a powder lubricant and a lubricating additive. As the powder ...lubricant, MoS3 was unfavorable for the tribological behavior of CDC coatings. Moreover, its friction and wear behaviors were worse than that of MoS2. As the lubricating additive, MoS3 was in-situ prepared within CDC coatings to obtain two kinds of CDC-MoS3 composites with different microstructures. The CDC-MoS3 composites showed lower friction than untreated CDC coatings and their tribological behavior was significantly affected by the microstructures.
Abstract
A non‐enzyme photoelectrochemical (PEC) glucose sensor based on α‐Fe
2
O
3
film is investigated. The α‐Fe
2
O
3
film was fabricated via a simple spin coating method. The proposed glucose ...sensor exhibits good selectivity, a fast response time of <5 s, a linear range of 0.05 to 6.0 mM, sensitivity of 17.23 μA mM
−1
cm
−2
and a detection limit of 0.05 μM. Meanwhile, the excellent performances of the α‐Fe
2
O
3
sensor were obtained in reproducibility and the long‐term stability under ambient condition. The linear amperometric response of the sensor covers the glucose levels in physiological and clinical for diabetic patients. Therefore, this non‐enzyme PEC sensor based on α‐Fe
2
O
3
film has a great potential application in the development of glucose sensors.
To investigate the clinical efficacy of insulin glargine combined with acarbose in the treatment of elderly patients with diabetes.
One hundred and forty-four elderly patients with diabetes who ...received treatment between December 2016 and December 2017 in Binzhou People's Hospital, China, were selected and divided into a control group and an observation group, 72 each, using random number table. The control group was treated with insulin glargine, while the observation group was treated with insulin glargine combined with acarbose. The therapeutic effect, improvement of quality of life and adverse reactions were compared between the two groups.
After treatment, fasting blood glucose (FBG), 2h postprandial blood glucose (PBG) and glycosylated hemoglobin (Hb Alc) of the two groups were lower than those before treatment, and the decrease degree of the observation group was significantly larger than that of the control group (P<0.05). The time needed for blood glucose reaching the standard level and daily insulin dosage of the observation group were significantly lower than that of the control group, and the differences were statistically significant (P<0.05). SF-36 scale score of the observation group was significantly better than the control group, and the difference was statistically significant (P<0.05). There was no significant difference in the incidence of adverse reactions between the two groups (P>0.05).
The combination of insulin Glargine and Acarbose can significantly control the blood glucose level of elderly patients with diabetes, improve the biochemical indicators, and enhance the quality of life. It is worth promotion in clinical practice.
Lightweight materials with a density less than 3 g/cmsup.3 as potential tribo-materials for tribological applications (e.g., space tribology) are always desired. Alsub.3BCsub.3 ceramic, a kind of ...ternary material, is one of the lightweight materials. In this study, dense Alsub.3BCsub.3 ceramic is prepared via a reactive hot-pressing process in a vacuum furnace. Its tribological properties are investigated in two unlubricated conditions (one is at elevated temperature up to 700 °C in air, and another is in a vacuum chamber of back pressures from 10sup.5 Pa to 10sup.−2 Pa at room temperature) and lubricated conditions (i.e., water and ethanol as low-viscosity fluids). At 400 °C and lower temperatures in air, as well as in vacuum, the tribological property of Alsub.3BCsub.3 ceramic is poor due to the fracture of grains and formation of a mechanically mixed layer. The beneficial influence of adsorbed gas species on reducing friction is very limited. Due to the formation of lubricious tribo-oxide at 600 °C and 700 °C, the friction coefficient is reduced from ca. 0.9 at room temperature and 400 °C to ca. 0.4. In the presence of low-viscosity fluids, a high friction coefficient and wear but a polished surface are observed in water, while a low friction coefficient and wear occur in ethanol. A lubricious carbide-derived carbon (CDC) coating on top of Alsub.3BCsub.3 ceramic through high-temperature chlorination can be fabricated and the wear resistance of CDC can be improved by adjusting the chlorination parameters. The above results suggest that Alsub.3BCsub.3 ceramic is a potential lubricating material for some tribological applications.
Under the new situation, China's power grid enterprises will face a situation of limited funding for operation and maintenance and increasing pressure on cost control. Therefore, further improving ...the scientificity of grid operation and maintenance investment allocation is of great significance to the operation and development of grid companies. Based on the problems of current operation and maintenance input allocation, this paper proposes a grid operation information entropy multi-attribute evaluation-based optimization technology for power network operation and maintenance input allocation, and combines empirical analysis to verify the scientific rationality of the allocation technology. The optimization technology can provide support for grid operation and maintenance investment decision-making and enterprise lean management.
Abstract
To elucidate the distribution and dispersion of RuO
2
species on the reactivity, RuO
2
−SnO
2
catalysts with 2 % and 5 % Ru contents have been prepared with impregnation (IMP), ...deposition‐precipitation (DP) and co‐precipitation (CP) methods, and probed by CO oxidation. With IMP and DP methods, RuO
2
crystallites are predominantly formed on the catalyst surface, which is favorable for CO oxidation. Moreover, the IMP catalyst possesses surface RuO
2
having smaller mean crystallite size and better dispersion than the DP catalyst, thus SnRuO‐IMP displays higher activity than SnRuO‐DP at the same Ru loadings. However, with CP method, RuO
2
species is mainly present as Ru
4+
cations in the lattice of rutile SnO
2
to form a solid solution structure below the lattice capacity, which is less reactive than the surface RuO
2
due to the restriction by the SnO
2
lattice. In conclusion, surface RuO
2
is revealed to be the active species, whose amount and dispersion determine the activity of the catalysts. By changing preparation methods, the distribution of RuO
2
species in the catalysts is varied and impacts the reactivity of the catalysts evidently. The traditional impregnation is found to be the best method to prepare RuO
2
−SnO
2
, which shows the highest activity among all the catalysts.
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