首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   16篇
  免费   0篇
化学工业   8篇
一般工业技术   7篇
原子能技术   1篇
  2023年   1篇
  2022年   6篇
  2021年   8篇
  2019年   1篇
排序方式: 共有16条查询结果,搜索用时 15 毫秒
1.
55 B2O3 – 15 SiO2 – 30 Na2O: x WO3, (x ranging from 0 to 5 wt%) glass composites were prepared according to the melt-quenching procedure. The prepared samples were characterized via X-ray diffraction and broad band dielectric spectroscopy (viz., dielectric constant (ε1), tanδ and AC conductivity (σAC) over a wide range of frequency and temperature). No sharp peaks were shown in the XRD pattern and is evidence of the amorphous nature of the samples. It turns out that the values of ε1 and ε2 are increasing at higher temperatures particularly at lower frequencies. The energy barrier height, WM values decreased as 0.27, 0.25 and 0.22 while showed value of 0.29 eV for 5.0 wt% WO3. In the dielectric modulus plots, two relaxation processes are found especially on the higher temperature side. It also shifted a higher frequency with increasing temperature. The values of exponent s have been found to lie between 0.48 and 0.74, which confirms that the conduction mechanism in the glass samples follows the correlated barrier hopping model. By calculating the activation energy associated with the relaxation processes and DC conductivity, it was found that the values are close, which indicates that the same charges contribute to the two processes.  相似文献   
2.
Journal of Materials Science: Materials in Electronics - Pseudo-capacitors are the emerging energy storage devices which forms a bridge between batteries and conventional capacitors. In the present...  相似文献   
3.
Different samples of xTeO2.(25-y)B2O3.zV2O5.yYb2O3 (or TBVY) new glass material were synthesized by the classical melt-quenching method. Structural, optical, physical, and thermal analyses of the synthesized glasses were performed in addition to Monte Carlo simulation to test radiation shielding properties. The results showed that increasing ratios of Yb2O3 (y = 0.0, 0.5, 1.0, and 1.5 mol%) produced monotonic density values of the synthesized glasses ranging from 4.70058 g cm?3 to 5.01038 g cm?3. XRD and FTIR analyses were used to confirm the glass structure of all samples. Optical transmittance and absorption parameters varied almost monotonically with increasing ratios of Yb2O3 indicating the ability to predict and control these properties using Yb2O3 additive. Furthermore, simulated radiation interaction parameters, such as attenuation coefficients and half-value layer, exhibited well-behaved dependence on the concentration ratio of the Yb2O3 additive. This approach to glass material synthesis demonstrate the useful synergetic effect of combining structural, optical, and radiation characteristics.  相似文献   
4.
Journal of Materials Science: Materials in Electronics - The radiation shielding characterization of glasses is vital in establishing their role in nuclear protection applications. This study...  相似文献   
5.
Journal of Materials Science: Materials in Electronics - Herein, Cu ions surface-doped Dy2O3 photocatalyst (Cu–Dy2O3) is synthesized utilizing hydrothermal technique to degrade methyl violet...  相似文献   
6.
Six different lithium bismuth boro-tungstate glasses with chemical composition 20Li2O-(20-x)Bi2O3-xWO3-60B2O3 (x = 0, 1, 2, 3, 4 and 5 mol%) were produced by the quenching method. Then, the glasses were investigated by means of their optical, mechanical, chemical durability and gamma ray shielding properties. Measured values of density and ultrasonic velocities were used to determine the elastic properties of the glasses. The optical band gap determined using the absorbance spectrum fitting (ASF) model was found to decrease under Bi2O3/WO3 substitution. The presence of BO3, BO4, BiO6, and WO4 structural groups in the glasses was confirmed by Fourier transform infrared spectroscopy (FTIR). The dissolution rate in the glass 20Li2O–15Bi2O3–5WO3–60B2O3 (LBWB5) was found to be 10 times lower than 20Li2O-20Bi2O3– 60B2O3. Mass attenuation coefficients (MAC) values of the produced glasses were determined using the MCNPX Monte Carlo code and Phy-X/PSD program. The photon attenuation parameters such as half value layer (HVL), mean free path (MFP), effective atomic number (Zeff), exposure buildup factor (EBF) and energy absorption buildup factor (EABF) were also studied. The obtained results showed that Bi2O3/WO3 substitution has a direct impact on the photon attenuation abilities of produced glasses. More specifically, HVL values increased from 0.252 × 10?2 cm for LBWB0 glass to 0.275 × 10?2 cm for LBWB5 glass. However, different trends were observed for the photon buildup factors for the produced glasses. It can be concluded that the produced glasses have promising structural, optical, and photon attenuation properties to be used for gamma shielding applications.  相似文献   
7.

Calcination temperature has influenced the structural and optical features of nanocrystalline (ZnO)0.8 (ZrO2)0.2 series. Indeed, at present, general research in the approach to synthesis of (ZnO)0.8 (ZrO2)0.2 nanoparticles by combustion using zinc nitrate hexahydrate (Zn (NO3)2·6H2O) and zirconium (11) nitrate pentahydrate (Zr (NO3)2·5H2O) is still in its infancy. A Thermogravimetric (TG) assessment was performed to determine the precursor of the conduction. Characterizations such as energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), transmission electron microscopy (TEM), UV–Visible, Fourier transform infrared spectroscopy (FTIR), and photoluminescence (PL) spectroscopy were carried out. The crystallite size of the binary oxides (ZnO)0.8 (ZrO2)0.2 on the maximum expansion of ZnO–ZrO2 nanoparticle was studied using Scherrer’s equation. Due to calcination, significant modifications were observed in terms of the size of the particles, the absorption spectra, and the intensity of the photoluminescence. In the XRD result, an increment in crystallinity was observed from 10.20 nm to 28.00 nm while the FTIR findings showed the removal of the polymer as well as the presence of nanoparticles metals. The optical band gap results indicated a decline in energy band gap between (3.27 and 3.12) eV for (ZnO)0.8 and (4.89–4.51) eV for (ZrO2) 0.2 nanoparticles. A photoluminescence result showed two individual peaks at 655 nm (1.89 eV) and 715 nm (1.73 eV) respectively. The study also showed the application which can be a suitable choice to be used in solar cell applications.

  相似文献   
8.
In this study, a series of Bi2O3 reinforced bariumtelluroborate (TBX) glasses with the nominal composition 20TeO2 + (50-x)B2O3 + 29.5BaO + xBi2O3 + 0.5Er2O3 (where x=0,5,10,15 and 20 in wt%) were manufactured using traditional melt-quenching method. The structural and compositional studies were performed by using XRD and FTIR spectra. In general, the glass matrix consists of the trigonal-planar and tetrahedral units of borates, tellurate and tellurite groups of tellurites, and the non-bridging oxygen (nBO). In addition to that, BiO3 and BiO6 groups are present in top-order glasses. The gamma-ray shielding (γ-RS) ability was evaluated through the vital parameters like the mass-attenuation coefficient (MAC), mean free-path (MFP), half-value layer (HVL), and effective atomic-number (Zeff). TB20 glass is happened to be the best candidate by giving the highest value for MAC and the lowest MFP and HVL, owing to its large density, 6.922 g/cm3. The fast neutron-removal cross-section (∑R) is assessed to investigate the neutron shielding capacity of TBX glasses. The γ-rays shielding properties of TBX glasses were observed better than some ordinary shields such as barite-concrete and commercial shielding glasses developed by SCHOTT Company.  相似文献   
9.
One of the newly light on processes utilized in applications for cleaning water is piezocatalysis. Mechanical vibrations generated through ultrasonication are generally used to separate out the charges in ferroelectric ceramics. The current research presents a novel prospective methodology of ball milling, where it is used as a facile and green technique for water remediation. The movement of the planetary ball mill imparts enough force such that reactive species are produced which are responsible for organic dye degradation. One of the results in the parametric analysis showed that by using 0.30 g of the 0.5Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Sr0.3)TiO3 (BST–BZT) powder, 62% of the methylene blue (MB) dye was degraded in 60 minutes.  相似文献   
10.
Journal of Materials Science: Materials in Electronics - This work deals with the study of the influence of adding AgI content on the physicochemical properties of...  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号