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Three gravity cores (LZK1, ZKA4, and CSJA6) from the incised Yangtze paleo-valley comprise a thick sequence of the post-glacial deposit. Nineteen genera (26 species) of the benthic foraminifers are described from these cores, with detailed down-core foraminiferal variations to investigate their paleoenvironmental implications. Three foraminiferal assemblages are recognized for the lower, middle, and upper parts of the cores respectively. The lower part is dominated by Ammonia beccarii var. and Florilus decorus with lower abundance and diversity. In the middle part, the foraminifers are abundant and diverse, dominated by both Ammonia beccarii var. and Elphidium advenum. Cavarotalia annectens, Pararotalia nipponica, and porcellaneous benthic foraminiferal forms are always present, sometimes abundant. The upper part is characterized by the Ammonia beccarii-Elphidium magellanicum assemblage, except for the Core ZKA4, which is barren of foraminifers in this interval. AMS 14C dates and foraminiferal assemblages both confirm that the transgression-regression sequence in these cores belongs to the “Ammonia transgression” during the Holocene. In addition to documenting the post-glacial sea-level fluctuations, the benthic foraminifers also reflect a warmer climate during the early–middle Holocene. The foraminiferal differences among the three cores can be used to interpret the influence of seawater during the post-glacial sea-level fluctuations. The area in the vicinity of Core ZKA4 was affected by marine water only during the middle Holocene, which was much shorter than the areas of the other cores.
In this paper, we proposed a simple approach to analyse the efficiency and propulsive characteristics of the high-altitude propeller in accordance to the Vortex Lattice Lifting line Method (VLM) theory, which is commonly used in preliminary design and parametric studies of propeller propulsion. The Computational Fluid Dynamics (CFD) method was used to obtain aerofoil aerodynamic data. The optimal pitch angle and propeller blade chord length (along the radial direction) can be calculated using the information from the database. The propeller wake model sees helical slipstreams applied to both lightly and moderately loaded propellers. The proposed method is capable of identifying the optimal efficiency through varying the number of propeller blades, radius and the rotational speed. The relationship between the optimal efficiency and design parameters is then established. This method was verified using CFD calculations.
Historically, alloy development with better radiation performance has been focused on traditional alloys with one or two principal element(s) and minor alloying elements, where enhanced radiation resistance depends on microstructural or nanoscale features to mitigate displacement damage. In sharp contrast to traditional alloys, recent advances of single-phase concentrated solid solution alloys (SP-CSAs) have opened up new frontiers in materials research. In these alloys, a random arrangement of multiple elemental species on a crystalline lattice results in disordered local chemical environments and unique site-to-site lattice distortions. Based on closely integrated computational and experimental studies using a novel set of SP-CSAs in a face-centered cubic structure, we have explicitly demonstrated that increasing chemical disorder can lead to a substantial reduction in electron mean free paths, as well as electrical and thermal conductivity, which results in slower heat dissipation in SP-CSAs. The chemical disorder also has a significant impact on defect evolution under ion irradiation. Considerable improvement in radiation resistance is observed with increasing chemical disorder at electronic and atomic levels. The insights into defect dynamics may provide a basis for understanding elemental effects on evolution of radiation damage in irradiated materials and may inspire new design principles of radiation-tolerant structural alloys for advanced energy systems.
Male and female Schistosoma japonicum worms have dissimilar appearances in their final host. In this study, a morphometric and morphological assessment of whole worms derived from unisexual and mixed infections in mice was conducted using confocal laser scanning microscopy. Worms from mixed infections showed significant morphological changes between 15 and 25 days post-infection (PI). On the fifteenth day PI, 33% of males had formed the conspicuous gynecophoric canal, but only 8% of them had testicular lobes containing a few germinative cells; 13% of females had incipient ovaries with a few immature ovarian cells inside. On the twentieth day PI, the testicular lobes contained more germinative cells in all male worms, while female worms presented vitelline glands. On the twenty-fifth day PI, more germinative cells were observed in the male testicular lobes, and differentiated cells were present in the female ovaries. All worms had fully developed reproductive organs from 30 days PI onwards. Morphometric analysis showed significant differences between mixed and unisexual infections at 35 days PI. Ovaries of worms from unisexual infections contained cells in one stage of maturation and vitelline glands had undifferentiated cells. Our study of S. japonicum provides a detailed comparison of different morphological traits from worms of mixed and unisexual infections throughout development.
The nucleus diameter/cell diameter (N/C) ratio and morphological characteristics of the haemocytes of the snail Babylonia areolata were studied using microscopy. Our results revealed two major types of haemocytes, namely granulocytes and hyalinocytes. In granulocytes, the cytoplasm was purplish red with Wright's staining, but it was blue in hyalinocytes. Hyalinocytes were smaller than granulocytes and had a higher N/C ratio. The granulocytes were sub-categorized into type I granulocytes and type II granulocytes based on the shape and the number of granules. Hyalinocytes were sub-categorized into large and small hyalinocytes based on the diameter and N/C ratio. Snails with a shell length from 2.7 to 3.3 cm showed no differences in the abundance of haemocytes.
To investigate the efficacy of biscuits fortified with different doses of vitamin A on improving vitamin A deficiency (VAD), anaemia and physical growth of pre-school children.
A randomised double-masked population-based field interventional trial with a positive control group.
Banan district of Chongqing, China.
A total of 580 pre-school children aged 3–6 years were randomly recruited into four groups. Children in groups I and II were given biscuits fortified with vitamin A at 30 % of the recommended daily intake (RDA) and 100 % of the RDA once a day for 9 and 3 months, respectively. Children in group III received biscuits containing 20 000 IU of vitamin A once a week for 3 months. Initially, the children in group IV received a 200 000 IU vitamin A capsule just once. At the beginning and end of the study, blood samples were collected to measure Hb, serum retinol, retinol-binding protein and prealbumin, and weight and height were measured.
All the fortification types significantly decreased the prevalence of VAD and anaemia in each group (P < 0·05). The effect of 9-month intervention on group I was the most efficient (P < 0·0045). After intervention, the Z-scores of height-for-age, weight-for-age and weight-for-height in all groups increased markedly compared with baseline (P < 0·05), but no significant difference was observed among the groups.
Data indicated that consuming vitamin A-fortified biscuits with daily 100 % RDA for 3 months has the same effect on the improvement of VAD, anaemia and physical growth as did the weekly 20 000 IU and single 200 000 IU administration in pre-school children.
We present an efficient polymer-small molecule triple-tandem organic solar cell (OSC), consisting of poly(3-hexylthiophene) (P3HT) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61 (PCBM) bulk heterojunction as the first and second cells, and small molecules copper phthalocyanine (CuPc) and fullerene (C60) as the third cell on top. These sub-cells are connected by an intermediate layer of Al(1 nm)/MoO3(15 nm), which appears to be highly transparent, structurally smooth, and electrically functional. Compared to our previous all polymer triple-tandem organic solar cells (2.03%), this polymer-small molecule triple-tandem organic solar cell achieves an improved power conversion efficiency of 2.18% with a short-circuit current density (Jsc) = 3.02 mA/cm2, open-circuit voltage (Voc) = 1.51 V, and fill factor (FF) = 47.7% under simulated solar irradiation of 100 mW/cm2 (AM1.5G), which can be attributed to the increased photocurrent generation in the third cell since the third cell has the complementary absorption with two bottom cells despite a slightly reduced Voc.
FePt:C films were prepared by filtered vacuum arc deposition. A strong
dependence of coercivity and ordering of the face-central tetragonal
structure on both C concentration and annealing temperature was observed.
With C concentration of 21%, the sample with a coercivity of 5.7 kOe was
obtained when annealing temperature was only 350 °C. Transmission
electron microscope observations revealed that FePt grains with an average
size of 4.1 nm were embedded in C and appeared to be well isolated.
Both interstitially Ag-doped Bi1.6Pb0.4Sr2Ca2Cu30y + x(wt%) Ag with x = 0.5, 1.0, 5.0, 10.0, 15.0, and substitutionally doped Bi1.6Pb0.4Sr2Ca2(Cu1-xAgx)0y with x = 0.025, 0.05, 0.10, 0.20, 0.40 systems were studied. Magnetic susceptibility Measurements indicate that both the interstitial and substitutional Ag-doping yield auch higher diaiagnetic signal for ZFC in a field of 60 0e at 5 K. At 80 K, -4πH/H was also enhanced by Ag-doping for H<200 Oe. Substitutionally Ag-doping also enhances the Magnetic critical current for x ≤ 0.2. Possible explanation was discussed.
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