We describe a facile, low-cost, and green method to fabricate porous graphene networks/nickel foam (PG/NF) electrodes by electrochemical deposition of graphene sheets on nickel foams (NFs) for the ...application of supercapacitor electrodes. The electrodeposition process was accomplished by electrochemical reduction of graphene oxide (GO) in its aqueous suspension. The resultant binder-free PG/NF electrodes exhibited excellent double-layer capacitive performance with a high rate capability and a high specific capacitance of 183.2 mF cm
-2
at the current density of 1 mA cm
-2
. Moreover, the specific capacitance maintains nearly 100% over 10,000 charge-discharge cycles, demonstrating a remarkable cyclic stability of these porous supercapacitor electrodes.
PACS
82.47.Uv (Electrochemical capacitors); 82.45.Fk (Electrodes electrochemistry); 81.05.Rm (Fabrication of porous materials)
•The strengthening of the Cf/AZ91D composites were realized by both TiO2 (sol-gel) and PyC (CVD) coatings on fiber.•The interfacial features of TiO2-Cf/AZ91D and the PyC-Cf/AZ91D composites related ...to strengthening were presented by TEM analysis.•The principle to select the coating of fiber was proposed by comparing the effectiveness and cost of the coatings.
In spite of the effectiveness of the fiber coatings on interface modification of carbon fiber reinforced magnesium matrix composites, the cost and exclusive equipment for the coatings preparation are usually ignored during research work. In this paper, pyrolytic carbon (PyC) and TiO2 were coated on carbon fiber surface to study the effects of fiber coatings on interfacial microstructure and mechanical properties of carbon fiber reinforced AZ91D composites (Cf/AZ91D composites). It was indicated that both the two coatings could modify the interface and improve the mechanical properties of the composites. The ultimate tensile strength of the TiO2-Cf/AZ91D and the PyC-Cf/AZ91D composite were 333MPa and 400MPa, which were improved by 41.7% and 70.2% respectively, compared with the untreated-Cf/AZ91D composite. The microstructure observation revealed that the strengthening of the composites relied on fiber integrity and moderate interfacial bonding. MgO nano-particles were generated at the interface due to the reaction of TiO2 with Mg in the TiO2-Cf/AZ91D composite. The volume expansion resulting from the reaction let to disordered intergranular films and crystal defects at the interface. The fibers were protected and the interfacial reaction was restrained by PyC coating in the PyC-Cf/AZ91D composite. The principle to select the coating of fiber was proposed by comparing the effectiveness and cost of the coatings.
Fe0 and Ni0 nanoparticles (NPs) of certain size were synthesized and added to the hydrogen production system from cotton stalk hydrolysate using Klebsiella sp. WL1316. Fe0 and Ni0 NPs with a size of ...50 nm at all concentrations effectively improve hydrogen production during mid to late fermentation stages; particularly, the highest daily hydrogen production obtained following treatment with 50 nm Fe0 NPs at 30 mg/L fermented for 96 h significantly increased by 61% comparing to the control treatment. The reducing sugar consumption in cotton stalk hydrolysate and ΔOD600 could be improved to some extent by Fe0 and Ni0 NPs supplementation. Addition of Fe0 or Ni0 NPs of 50 nm at a concentration of 30 mg/L resulted in enhanced cumulative hydrogen production with improvement of hydrogen yield reached higher than 20%, and the values of Y(H2/S) were all higher than 90 mL/g substrate, reflecting good hydrogen production and substrate consumption. The analysis of the main soluble metabolites profile revealed that supplementation with Fe0 and Ni0 NPs of suitable size and concentration may decrease the metabolic flux in the competitive branch of hydrogen production and increase the metabolic flux of the key node that leads to hydrogen generation, thus promoting biohydrogen synthesis.
•Fe0 and Ni0 NPs with suitable size and concentration enhanced hydrogen production.•Suitable Fe0 and Ni0 NPs addition improved sugar consumption and bacterial growth.•Emphasize NP size effect on enhancement of hydrogen production for the first time.•Daily hydrogen production increased by 61% upon optimum Fe0 NPs addition at 96 h.•Hydrogen yield enhanced higher than 20% upon optimum Fe0 and Ni0 NPs addition.
Under the influence of the conversion of farmland to forest and rapid urbanization, the traditional rural settlements in the hilly and gully region of the loess plateau are experiencing problems, ...such as hollowing and decline, due to the difficulty in adapting to changes in social relations. With Angou Watershed as an example, a research framework of “gravity identification-network evaluation-spatial optimization” is constructed, which is used to analyze the characteristics of the network as a whole, regions and nodes. In addition, social network analysis is employed to reveal the spatial pattern of rural settlements in the watershed. According to the findings, the lack of close ties of communities within the watershed makes it difficult to achieve close social interactions and services. Divided by region, 8 settlement groups are formed, but there is a lack of cohesion and cooperation among the settlement groups. The proportion of marginal settlement nodes is as high as 39.13%, resulting in the serious shortage of motivation for village development. Finally, a three-level rural settlement system is proposed, and 8 hub villages are added, which play a connecting role of tableland-type villages. In order to form a complete industrial chain, the central settlement processing industry is intensively cultivated. Through the reconstruction of the four cluster development groups, the north-south connection of the watershed is strengthened. By defining the number of villages of three types of leader, key position and explorer, the development direction is clarified. This study not only has a significant guiding role in the coordinated development of rural settlements in small watersheds in the hilly and gully areas of the loess plateau, but also provides an important basis for regional urban and rural overall planning, village layout, as well as resource allocation and construction.
We report a facile, low-cost and green route to fabricate platinum nanoparticle (Pt NP) decorated three-dimensional (3D) graphene assembled on fluorine-doped tin oxide (FTO) electrodes (Pt/3D-G/FTO) ...with enhanced electrocatalytic activity. The fabrication process was accomplished by preparation of 3D graphene (3D-G/FTO) electrodes through electrochemical reduction of a graphene oxide suspension followed by electrodeposition of Pt NPs onto them. The Pt/3D-G/FTO electrode exhibits much higher catalytic activity and better stability for methanol oxidation compared with the electrodes prepared by electrodeposition of Pt NPs onto two-dimensional graphene sheets substrate (Pt/G/FTO) or bare FTO (Pt/FTO) under the same condition. These enhancements can be attributed to the high surface area, large void volume and high electrical conductivity as well as smaller size of Pt NPs in the hollows of the 3D architecture and a large amount of ridges on it.
•Pt/3D-G/FTO was prepared by a facile, convenient, inexpensive and green method.•Pt/3D-G/FTO exhibits much enhanced catalytic activity and better stability for MOR.•3D graphene possesses high surface area, large void volume and high conductivity.•The catalytic ability of Pt/3D-G/FTO raised with the deposition potential.•Pt/3D-G/FTO prepared by CV deposition shows the largest methanol oxidation ability.
Abstract Patterns on polymers usually have different mechanical properties as those of the substrates, causing deformation or distortion and even detachment of the patterns from the polymer ...substrates. Herein, we present a wrinkling strategy, which utilizes photolithography to define the area of stress distribution by light-induced physical crosslinking of polymers and controls diffusion of residual solvent to redistribute the stress and then offers the same material for patterns as substrate by thermal polymerization, providing uniform wrinkles without worrying about force relaxation. The strategy allows the recording and hiding of up to eight switchable images in one place that can be read by the naked eye without crosstalk, applying the wrinkled polymer for optical anti-counterfeiting. The wrinkled polyimide film was also utilized to act as a substrate for the creation of fine copper circuit by a full-additive process. It generates flexible integrated circuit (IC) carrier board with copper wire density of 400% higher than that of the state-of-the-art in industry while fulfilling the standards for industrialization.
Purpose
This study aimed to evaluate the angiogenesis‐related factors of the vascular endothelial growth factor (VEGF) family in the aqueous humour of patients with neovascular glaucoma (NVG).
...Methods
This study involved 22 eyes of 22 patients with advanced NVG requiring antiglaucomatous surgery and 20 control subjects with cataracts. The NVG eyes received an intravitreal injection of ranibizumab (IVR) treatment before antiglaucomatous surgery. Aqueous humour and blood were collected at the time of IVR and cataract surgery. Protein concentration of VEGF‐A, VEGF‐B and placenta growth factor (PlGF) in aqueous humour and plasma was determined by ELISA tests.
Results
The mean concentration (standard deviation) of VEGF‐A and PlGF in the aqueous humour of patients with NVG were 3037 (2387) pg/ml and 1078 (712) pg/ml, respectively; both were significantly higher than the control group (both p < 0.001). However, levels of VEGF‐A and PlGF in the serum of NVG and control subjects remained low. High concentrations of VEGF‐A were closely correlated with high levels of PlGF in patients with NVG (r = 0.593, p = 0.004). Concentrations of VEGF‐B in aqueous humour and serum remained unchanged (p > 0.05).
Conclusion
There were high concentrations of angiogenesis factors of the VEGF family, with the exception of VEGF‐B, in the aqueous humour of patients with NVG, and there was a positive correlation between VEGF‐A and PlGF. High PlGF levels in patients with NVG may provide another potential target for treatment of NVG.
The great northern snakehead (
) is one of the most important economic and conservational fish in China. In this study, the melanocytes in the skin of two distinct color morphs
were investigated and ...compared through employment of the microscopic analysis, hematoxylin and eosin (H&E) and Masson Fontana staining. Our results demonstrated the uneven distribution of melanocytes with extremely low density and most of them were in the state of aging or death. Meanwhile, there was no obvious pigment layer and melanocytes distribution pattern found in the albino-type (AT), while the melanocytes were evenly distributed with abundance in the bicolor-type (BT). The transcriptome analysis through Illumina HiSeq sequencing showed that a total of 34.93 Gb Clean Data was obtained, and Q30 base percentage reached 92.66%. The BT and AT northern snakeheads transcriptome data included a total of 56,039,701 and 60,410,063 clean reads (
= 3), respectively. In gene expression analyses, the sample correlation coefficients (
) were ranged between 0.92 and 1.00; the contribution of PC1 and PC2 were 50.25 and 13.73% by using PCA cluster analysis, the total number of DEGs were 1024 (559 up-regulated and 465 down-regulated), and the number of annotated DEGs was 767 (COG 172, KEGG 262, GO 288, SwissProt 548, Pfam 579 and NR 765). Additionally, 46,363 ± 873 and 44,947 ± 392 single nucleotide polymorphisms (SNPs) were compiled via genetic structure analysis, respectively. Ten key pigment-related genes were screened using qRT-PCR. And all of them revealed extremely higher expression levels in the skin of BT than those of AT. This is the first study to analyze the mechanism of albino characteristics of
via histology and transcriptomics, and also provide the oretical and practical support for the protection and development of germplasm resources for
.
Dual mTORC1/2 inhibitors may be more effective than mTORC1 inhibitor rapamycin. Nevertheless, their metabolic effects on breast cancer cells have not been reported. We compared the anti-proliferative ...capacity of rapamycin and a novel mTORC1/2 dual inhibitor (AZD8055) in two breast cancer cell lines (MDA-MB-231 and MDA-MB-453) and analyzed their metabolic effects using proton nuclear magnetic resonance (
1
H NMR) spectroscopy-based metabolomics. We found that AZD8055 more strongly inhibited breast cancer cell proliferation than rapamycin. The half-inhibitory concentration of AZD8055 in breast cancer cells was almost one-tenth that of rapamycin. We identified 22 and 23 metabolites from the
1
H NMR spectra of MDA-MB-231 and MDA-MB-453 cells. The patterns of AZD8055- and rapamycin-treated breast cancer cells differed significantly; we then selected the metabolites that contributed to these differences. For inhibiting glycolysis and reducing glucose consumption, AZD8055 was likely to be more potent than rapamycin. For amino acids metabolism, although AZD8055 has a broad effect as rapamycin, their effects in degrees were not exactly the same. AZD8055 and rapamycin displayed cell-specific metabolic effects on breast cancer cells, a finding that deserves further study. These findings help fill the knowledge gap concerning dual mTORC1/2 inhibitors and provide a theoretical basis for their development.
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