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排序方式: 共有196条查询结果,搜索用时 15 毫秒
61.
Gravimetrische Untersuchungen mit Hilfe einer Thermowaage zum Schwefeltransport zwischen siliziumhaltigen, kohlenstoffgesättigten Eisenschmelzen und CoO-Al2O3-Schlacken bei 1490 und 1550°C unter oxydierenden Bedingungen. Vergleich der Ergebnisse mit bereits vorliegenden volumetrischen Untersuchungen. Erörterung der Versuchsergebnisse mit Hilfe der Ionentheorie der Schlacke. Einfluß von Mangan, Silizium, Titan und Kohlenstoff auf den Anteil des Schwefeltransportes bei oxydierenden Bedingungen. 相似文献
62.
The dynamic behaviour of binary blends of linear polystyrene fractions in the terminal zone of the relaxation spectrum presents interesting peculiarities which have been discussed in a previous paper by Montfort. The viscoelastic properties are characterized by a representation in the complex plane of viscosities. In this paper, we propose an empirical blending law which represents such behaviour over a large range of frequencies. The conclusions of this law on the limiting values of η0 and J0e are compared with those deduced from the blending laws of Graessley and BMEO. 相似文献
63.
Untersuchung des Übergangs des Schwefels aus kohlenstoffhaltigen Eisenschmelzen mit Zusätzen von Silizium, Mangan und Titan in flüssige Kalk-Tonerde-(Kieselsäure)-Schlacken. Vergleich der Ergebnisse mit einem früher abgeleiteten kinetischen Modell mit der Austauschreaktion an der Phasengrenzfläche als geschwindigkeitsbestimmenden Schritt. Aussagen über die gegenseitige Beeinflussung von Kieselsäurereduktion und Schwefeltransport von Metall in die Schlacke. Einfluβ von Mangan- oder Titanzusätzen zur Schmelze auf den Schwefeltransport und die Kieselsäurereduktion. 相似文献
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65.
Ivan Stoevski Arman Bonakdarpour Baizeng Fang Sharon Ting Voon David P. Wilkinson 《国际能源研究杂志》2021,45(1):220-230
Batteries with manganese (di)oxide/zinc chemistry and aqueous‐based electrolytes have the potential to address energy storage demands of stationary applications primarily because of the abundant availability of Zn and Mn‐oxides, their intrinsic low cost, and the high specific/volumetric charge capacities. Herein, we report the use of Mn3O4 (hausmannite phase of manganese oxide) as the positive electrode material in a rechargeable near‐neutral Mn‐oxide/Zn battery configuration. Electrochemical investigations reveal that the hausmannite phase can activate for charge/discharge processes during the first 40 to 50 cycles and then a maximum capacity is obtained. This material shows excellent reversibility (~800 cycles) in keeping more than 65% of its maximum capacity. For the first time, the hausmannite activation mechanism was better understood under near‐neutral conditions. By using different characterization techniques (X‐ray powder diffraction [XRD], inductively coupled plasma‐optical emission spectrometry [ICP‐OES], X‐ray photoelectron spectroscopy [XPS], and energy dispersive X‐ray spectroscopy [EDS]) formation of Zn‐based compounds at the electrode surface was confirmed. One of the compounds formed is the layered double hydroxide (Zn4SO4[OH]6 · 5H2O) that forms as a side product. No direct evidence for intercalation of zinc ions was observed. Electrochemical experiments in different aqueous/organic electrolytes has shown that proton intercalation plays a significant role in the charge‐storage mechanism, while the activation process itself proceeds, most likely, through the formation of Zn‐species at the electrode surface. 相似文献
66.
Mahsa Baazm Ehsan Soheyli Mohammad Hossein Hekmatshoar Arman Rostamzad Abouzar Karami Cheragh Abad 《Ceramics International》2018,44(8):9414-9421
In this paper, the glass composition of (50-x)P2O5-xB2O3-30CuO-20Li2O (x?=?0, 5, 10, 15, and 20?mol%) was prepared and the effect of P2O5 substitution by B2O3 on their structural, optical, switching, and antibacterial characteristics was studied. FT-IR spectra showed that an increase in the B2O3 content leads to gradual erosion of the phosphate characteristic bonds, and the emergence of borate-related ones by creating new linkages between phosphate chains through P–O–B bonds and formation of highly cross-linked P3-O-B4 linkages. The incorporation of boron up to 20?mol%, also leads to an overall increase in glass transition temperature together with a decrease in the molar volume which both, implied improvement of glass stability. Optical studies revealed that all glasses are almost transparent in the UV–Vis region with high band gap energy about 3.83?eV, which experiences a red-shift with increase in the B2O3 concentration to 15?mol%. By calculating the wavelength-dependent optical parameters, however, it was found that the present glass composition with highest concentration of B2O3 shows refractive index near one and very negligible extinction coefficient (and imaginary optical dielectric function) at the visible region. These results support the great potential of the mentioned glass composition as a window layer. The analysis of the high electric field measurements demonstrated a wide range reduction in switching threshold voltage as the B2O3 content increases. This hints at their potential application as electrical-induced sensors. The antibacterial activity of x?=?0 and x?=?5 glass compositions has been examined by zone of inhibition measurements and it was found that they have potential applications as antibacterial agent. 相似文献
67.
68.
Arman Hasan Abdelghany Osman Saima Mahmoud Abu Aldahan Ala Mahmoud Bahaa Hussein Saber Fowler Abdel-Rahman 《Bulletin of Engineering Geology and the Environment》2021,80(6):4221-4233
Bulletin of Engineering Geology and the Environment - Petrological features of carbonate rocks that exert control on their mechanical and physical properties are examined in the study presented... 相似文献
69.
A series of La1−xSbxFeO3 was prepared using the conventional solid state method. XRD revealed the formation of the orthorhombic structure with space group Pbnm. The data showed that, the molar magnetic susceptibility and coercive field HC were increased from 9.16 × 10−3 to 26.9 × 10−3 emu g−1 mol and 1196 to 5465 Oe from for LaFeO3 to La0.95Sb0.05FeO3, respectively. The coercive field (HC) of the sample with x = 0.05 increased 6 times than that of the parent LaFeO3 and the saturation magnetization (Ms) was increased from 0.1614 emu g−1 for the parent LaFeO3 to 0.2654 emu g−1 for the doped sample. The dielectric constant (?′) was increased with increasing the Sb3+ content. The ac conductivity (σ) increases from 2.36 × 10−3 Ω−1 m−1 for the LaFeO3 to 30 × 10−3 Ω−1 m−1 for the sample La0.95Sb0.05FeO3 at T = 553 K and frequency 1 MHz. The sample La0.95Sb0.05FeO3 is concluded to be a novel single phase multiferroic material. 相似文献
70.
In this communication we describe a segmentation technique which combines two properties in an iterative and hierarchial matter to correctly segment and classify the given cell images. The technique is applied to digital images taken from microscope slides of cultured rat liver cells, and the goal is to classify these cells into one of three possible classes. The first class cells (I) are morphologically normal and stain the darkest. The second class cells (II) are slightly damaged showing both nuclear and cytoplasmic swelling with resultant lessening of staining affinity. The third class cells (III) are markedly damaged as demonstrated by the presence of cytoplasmic vacuolization, or are completely disintegrated. First class cells are classified by taking advantage of their staining affinity; the original gray level image is segmented into four gray levels. The darkest is then classified as type I. Type III cells are classified by using high business as a characteristic; the standard deviation of the original image is segmented into four business levels. The highest level is classified as type III cell. Assuming only the three cell types are present in any given image, the remaining non-background unclassified pixels are determined to belong to type II cells. 相似文献