The effects of sintering temperature and Bi2O3 content on the microstructure and magnetic properties of lithium-zinc (LiZn) ferrites prepared by a conventional ceramic method were investigated. The ...results show that the densification behavior and grain growth rate were greatly improved by the addition of Bi2O3, because a liquid phase sintering occurred during the sintering process at high temperature due to the low-melting point of Bi2O3 (825 deg C). X-ray diffraction (XRD) patterns of the slightly doped samples did not reveal the appearance of any phase other than spinel LiZn ferrite. However, the secondary phase of perovskite BiFeO3 was detected for Bi2O3 content of more than 0.25wt%. The studies further show that Bi oxide was present at grain boundary, and promoted the grain growth as reaction center at lower temperature. A high saturation magnetization, squareness ratio, minimum ferromagnetic resonance linewidth and low coercive force were obtained for the sample with 1.00wt% Bi2O additive at lower sintering temperature (1100 deg C).
This work demonstrates the dependence between magnetic properties and the thickness of NiFe thin films. More importantly, a quantitative study of the surface composition of NiFe thin film exposed to ...atmospheric conditions has been carried out employing angle-resolved X-ray photoelectron spectroscopy (ARXPS). In this study, we fabricated Ni81Fe19 (NiFe) thin films on Si (100) substrate using electron beam evaporation and investigated their surface morphologies, magnetic properties, and the thickness of the surface oxide layer. The coexistence of metallic and oxidized species on the surface are suggested by the depth profile of ARXPS spectra. The thickness of the oxidized species, including NiO, Ni(OH)2, Fe2O3, and Fe3O4, are also estimated based on the ARXPS results. This work provides an effective approach to clarify the surface composition, as well as the thickness of the oxide layer of the thin films.
The relationship between the progression of hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) and the gut microbiota is poorly understood, and an HBV-ACLF-related microbiome has yet ...to be identified. In this study alterations in the fecal microbiome of 91 patients with HBV-ACLF (109 stool samples), including a cohort of nine patients at different stages of HBV-ACLF, were determined by high-throughput 16S rDNA sequencing. The operational taxonomic units and Shannon indexes indicated that the diversity and abundance of the gut microbiome significantly decreased with the progression of HBV-ACLF (p <0.05). The relative abundance of the
phylum in the microbiome was significantly reduced, whereas the abundance of potentially pathogenic bacteria, such as
,
,
, and
, was highly enriched in the HBV-ACLF group compared with the healthy control group. The abundance of
was negatively correlated with the level of serum alpha fetoprotein, and the abundance of
was positively correlated with serum total bilirubin (TBIL). Furthermore, the abundance of
was significantly negatively correlated with the level of serum TBIL and the international normalized ratio and positively correlated with prothrombin time activity. Our findings suggest that the gut microbiota plays an important role in the development of HBV-ACLF.
•Wind power utilization over existing urban high-rise buildings is promising.•An integrated method of both macro and micro aspect analysis is recommended.•1.3–5.4 times of wind power enhancement ...above the roof.•4-times enhancement is even larger than 2.7 times from general model.•This study helps analyze, locate, and design wind turbines around buildings.
To help design wind turbines around numerous high-rise buildings with promising wind in Hong Kong, this paper presents an integrated method of both macro (weather data and domain topography) and micro aspect (Computational Fluid Dynamics, CFD) analysis. Long-term wind data are compared at dense urban and small island stations. The prevailing wind is found to be from the East, and the average wind speed for the urban location is much lower, say 2.93m/s at 25m above ground level. The need to integrate wind turbines into high-rise buildings is necessary. This research demonstrates that the wind power density at 4m above the building roof is enhanced numerously by 1.3–5.4 times with 5–7m/s inlet velocity. Wind power utilization around the windward top roof is the most promising under the dominant wind direction. The thickness of wind speed below 8m/s is only 3.6m at these areas. Due to high-rise building height and concentration effects, the wind power enhancement for 7m/s inlet velocity is around 4 times of that for 5m/s, which is even larger than the cube of these two velocity ratio 7/5, i.e. 2.7 times determined from the general model between wind power and velocity.
A Gram-stain-negative, aerobic, non-motile, yellow-pigmented rod-shaped and alginate-degrading bacterium, designated B1N29
T
, was isolated from the gut of the abalone
Haliotis rubra
obtained in ...Weihai, China. Strain B1N29
T
was found to grow at 4–35 ℃ (optimum, 25 ℃), at pH 6.5–9.0 (optimum, 7.0–7.5) and in the presence of 0.5–9% (w/v) NaCl (optimum, 2%). Cells were positive for oxidase and catalase activity. The 16S rRNA-based phylogenetic analysis revealed that the nearest phylogenetic neighbors of strain B1N29
T
were
Tamlana carrageenivorans
KCTC 62451
T
(98.2%) and
Tamlana agarivorans
KCTC 22176
T
(97.7%). Based on the phylogenomic analysis, the average nucleotide identity (ANI) values between strain B1N29
T
and the neighbor strains were 79.2 and 79.0%, respectively; the digital DNA–DNA hybridization (dDDH) values between strain B1N29
T
and its two closest neighbors were 22.8 and 23.0%, respectively. Menaquinone-6 (MK-6) was detected as the sole respiratory quinone. The dominant cellular fatty acids were iso-C
15:0
, iso-C
17:0
3-OH, anteiso-C
15:0
and iso-C
15:1
G. The polar lipids included phosphatidylethanolamine, one aminophospholipid, seven aminolipids and five unidentified lipids. Based on the phylogenetic and phenotypic characteristics, strain B1N29
T
is considered to represent a novel species of the genus
Tamlana
, for which the name
Tamlana haliotis
sp. nov. is proposed. The type strain is B1N29
T
(= KCTC 72683
T
= MCCC 1H00394
T
).
A flexible viologen carboxylic acid derivative forms single‐ and triple‐stranded helices by hydrogen‐bonding interactions, and undergoes pH‐triggered helical transformation by a water‐mediated ...solid‐state conversion (see picture). This transformation is accompanied by a fluorescence signal change that can be directly observed by the naked eye under a UV lamp.
Most of the offshore wind turbines (OWT) recently installed in Europe, China and North America are in shallow water. However, unlocking the full potential of OWT lies in deeper waters. Jacket ...substructures have presented themselves as a reliable foundation concept for transitional water depth. This study focuses on the structural static and dynamic analysis of the traditional jacket substructures (with X and K bracing) and the recently patented three-legged twisted jackets (with a twisted angle of 30 and 60 degrees) for deployment in transitional water (beyond 60 m). To facilitate comparison, the dimensions of all the jackets remain the same, while, the geometric configurations are distinct. Static analysis was implemented to better understand the global load bearing behaviour of the jackets. First, the global displacement patterns at the tower top are compared. The individual reactions at mud-line were investigated, followed by the evaluation of the maximum von Mises stress. Subsequently, this research went on to investigate the effect of dynamic loading. In this dynamic analysis, three main critical points were considered, including the wave point (67 m), the platform and the tower top. A modal analysis was performed to compute the mode shapes and natural frequencies for all the jackets. The first five modes of all the jackets were also checked against the results available for the OC4 project. A similar analytical approach was adopted for the structural design of monopile or tripod foundations for offshore wind turbines. The results showed that in the static analysis both the traditional jackets and the twisted jackets were safe under the provided load combination. The twisted jacket proved to possess excellent structural behaviour compared to the traditional four-legged jackets, while maintaining the merits of lower material usage with fewer nodes. Analysing the von Mises stress revealed that the maximum stress occurred at the transition piece and close to the working platform. The modal analysis results of the jackets demonstrated that the twisted jackets (30 and 60 degrees) with the first natural frequency of 0.29 and 0.31 Hz fell under the soft-stiff design category whereas the traditional four-legged jackets were classified as stiff-stiff designs. The discovered structural performance of OWTs equipped with various jacket foundations contributes to the preliminary structural selection and optimal design of foundations of OWTs to be installed in transitional water.
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