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1.
In this work, we designed a magnetically-separable Fe3O4-rGO-ZnO ternary catalyst, ZnO anchored on the surface of reduced graphene oxide (rGO)-wrapped Fe3O4 magnetic nanoparticles, where rGO, as an effective interlayer, can enhance the synergistic effect between ZnO and Fe3O4. The effects of three operational parameters, namely irradiation time, hydrogen peroxide dosage, and the catalyst dosage, on the photo-Fenton degradation of methylene blue and methyl orange were investigated. The results showed that the Fe3O4-rGO-ZnO had great potential for the destruction of organic compounds from wastewater using the Fenton chemical oxidation method at neutral pH. Repeatability of the photocatalytic activity after 5 cycles showed only a tiny drop in the catalytic efficiency.  相似文献   
2.
In flash sintering experiments, the thermal history of the sample is key to understanding the mechanisms underlying densification rate and final properties. By combining robust temperature measurements with current-ramp-rate control, this study examined the effects of the thermal profile on the flash sintering of yttria-stabilized zirconia, with experiments ranging from a few seconds to several hours. The final density was maximized at slower heating rates, although processes slower than a certain threshold led to grain growth. The amount of grain growth observed was comparable to a similar conventional thermal process. The bulk electrical conductivity correlated with the maximum temperature and cooling rate. The only property that exhibited behavior that could not be attributed to solely the thermal profile was the grain boundary conductivity, which was consistently higher than conventional in flash sintered samples. These results suggest that, during flash sintering, athermal electric field effects are relegated to the grain boundary.  相似文献   
3.
Wireless Networks - Orthogonal frequency-division multiplexing with random multiple access (OFDRMA) is discussed for down-link communications, whereby a single base-station transmits information...  相似文献   
4.
The phospholipid composition of lipoproteins is determined by the specificity of hepatic phospholipid biosynthesis. Plasma phospholipid 20:4n-6 and 22:6n-3 concentrations are higher in women than in men. We used this sex difference in a lipidomics analysis of the impact of endocrine factors on the phospholipid class and molecular species composition of fasting plasma from young men and women. Diester species predominated in all lipid classes measured. 20/54 Phosphatidylcholine (PtdCho) species were alkyl ester, 15/48 phosphatidylethanolamine (PtdEtn) species were alkyl ester, and 12/48 PtdEtn species were alkenyl ester. There were no significant differences between sexes in the proportions of alkyl PtdCho species. The proportion of alkyl ester PtdEtn species was greater in women than men, while the proportion of alkenyl ester PtdEtn species was greater in men than women. None of the phosphatidylinositol (PtdIns) or phosphatidylserine (PtdSer) molecular species contained ether-linked fatty acids. The proportion of PtdCho16:0_22:6, and the proportions of PtdEtn O-16:0_20:4 and PtdEtn O-18:2_20:4 were greater in women than men. There were no sex differences in PtdIns and PtdSer molecular species compositions. These findings show that plasma phospholipids can be modified by sex. Such differences in lipoprotein phospholipid composition could contribute to sexual dimorphism in patterns of health and disease.  相似文献   
5.
Journal of Materials Science: Materials in Electronics - The main weakness of polymer gas sensors is its stability. Here, we report stability enhancement of a 100 nm polypyrrole (PPy) thin...  相似文献   
6.
Composite flours were prepared from blends of yellow maize (Zea mays), sesame seed (Sesamum indicum) and oyster mushroom (Pleurotus ostreatus) powder in the ratio of 80:20:0; 75:20:5; 70:20:10; 65:20:15 and 60:20:20, respectively to produce the cereal-based breakfast product coded as YSB, SMB, TMB, PMB and OMB with YSB as the control. The breakfast cereals were produced by hydration and toasting of yellow maize and sesame to 160°C for 25 min and blended together with oven-dried and packaged oyster mushroom. The developed products were analysed for proximate, vitamins, minerals and sensory properties. The proximate composition (%) of different blends ranged as moisture (4.07–7.08), ash (3.09–2.28), crude fat (16.04–12.83), crude fibre (4.30–8.22), protein (16.14–22.54), carbohydrate (56.34–47.04) and energy (434.34–393.83 Kcal). Vitamin A (7.99–5.98 mg/100 g), vitamin B1 (0.08–0.42 mg/100 g), vitamin B2 (0.06–0.15 mg/100 g), vitamin B3 (1.91–4.52 mg/100 g) and vitamin C (3.55–3.32 mg/100 g) were u while minerals (mg/100 g) were calcium (75.31–58.02), potassium (0.65–4.01), magnesium (12.25–12.62), iron (1.21–4.15) and zinc (0.40–1.32). Sensory scores revealed that the cereal-based breakfast product were acceptable to the panellist with oyster mushroom supplementation up to 10%.  相似文献   
7.
Wireless Personal Communications - The importance of environmental pollution has motivated the researchers to investigate the electrical power consumption of any emerging technology. Edge Computing...  相似文献   
8.
Multimedia Tools and Applications - In this paper, blind image quality assessment (IQA) of Gaussian blurred images based on Discrete Fourier Transform (DFT) is proposed. The proposed work is based...  相似文献   
9.
Vieira  Elizabeth S. 《Scientometrics》2022,127(5):2747-2772

It is widely recognised that science in Africa will benefit from international research collaboration (IRC), and therefore studies have been done on IRC in Africa (hereafter: Africa-related IRC research). However, there is no information on the development of Africa-related IRC research, the geographical location of the scientists interested in the topic, the visibility of the literature and the themes researched. This information makes it possible to understand relevant aspects in the context of IRC in Africa, which are useful for identifying IRC strengths, weaknesses and opportunities. It also allows paving the way for future research on this topic. Using discipline–specific terms, bibliometric, and thematic analysis, I collected the literature on Africa-related IRC research indexed in the Web of Science Core Collection (WoS). The results showed that the number of publications on the topic has increased, few African countries have researched the topic, a third of the publications were written exclusively by African scientists, and the topic has high visibility. The panoply of publications revealed that patterns, driving factors, effects, networks, asymmetries, and policies concerning IRC were the main themes researched.

  相似文献   
10.
Hemorphins are known for their role in the control of blood pressure. Recently, we revealed the positive modulation of the angiotensin II (AngII) type 1 receptor (AT1R) by LVV-hemorphin-7 (LVV-H7) in human embryonic kidney (HEK293) cells. Here, we examined the molecular binding behavior of LVV-H7 on AT1R and its effect on AngII binding using a nanoluciferase-based bioluminescence resonance energy transfer (NanoBRET) assay in HEK293FT cells, as well as molecular docking and molecular dynamics (MD) studies. Saturation and real-time kinetics supported the positive effect of LVV-H7 on the binding of AngII. While the competitive antagonist olmesartan competed with AngII binding, LVV-H7 slightly, but significantly, decreased AngII’s kD by 2.6 fold with no effect on its Bmax. Molecular docking and MD simulations indicated that the binding of LVV-H7 in the intracellular region of AT1R allosterically potentiates AngII binding. LVV-H7 targets residues on intracellular loops 2 and 3 of AT1R, which are known binding sites of allosteric modulators in other GPCRs. Our data demonstrate the allosteric effect of LVV-H7 on AngII binding, which is consistent with the positive modulation of AT1R activity and signaling previously reported. This further supports the pharmacological targeting of AT1R by hemorphins, with implications in vascular and renal physiology.  相似文献   
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