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201.
Masao Taki 《IEEJ Transactions on Electrical and Electronic Engineering》2016,11(6):683-695
Research works on bioelectromagnetics in Japan are reviewed with a focus on the efforts devoted to the issue of human protection from electromagnetic field (EMF) exposures. History of this issue in Japan is briefly reviewed first for all EMF spectra. Then research works on radiofrequency (RF) EMF are summarized in more detail. The RF studies reviewed are mainly conducted in the framework of research program by the Ministry of Internal Affairs and Communications (MIC) started in 1997. Because of this program, collaborations between biology/medicine and engineering have been promoted. The results consistently show no evidence against the safety of RF‐EMF within the exposure levels of internationally accepted guidelines. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
202.
The use of process bus modern technology in accordance with the IEC 61850 protocol allows performing modern measurement and improving the protection automation system. It also allows for the integration and complex building of functional automation and control systems based on network devices in Ethernet technology. The paper presents measuring tests of a process bus equipment and the operation of protection functions based on measurements. 相似文献
203.
随着现代化电力工业的发展和家用电器的普及,环境极低频电磁场的磁感应强度越来越高,因此,公众日益关注极低频电磁场暴露对人体健康的可能危害。为此,主要对近年来有关极低频电磁场暴露与不良妊娠结局发生关系的流行病学研究进展进行了综述,总结了以往研究存在的问题并展望了未来的研究方向。目前研究集中于高压输电线路及视频显示终端来源的极低频电磁场对出生体质量、流产、早产及出生缺陷。有限研究提示妊娠期极低频电磁场暴露与低出生体质量、流产发生存在相关性,但是剂量-反应关系尚不明确,结果有待验证;研究结果未支持极低频电磁场与早产和出身缺陷有关。流行病学研究对极低频电磁场是否能增加不良妊娠结局的发生风险没有得到一致结果。 相似文献
204.
In this work, the synthesis and characterization of ZnS nanoparticles prepared via two approaches, involving the thermal decomposition of the precursor complex in a furnace (pyrolysis) and by solvothermal process in the presence of hexadecylamine (HDA-ZnS), are reported. The precursor complex, Zinc (II) bis (N,N-diallyl dithiocarbamate), was synthesized and characterized by spectroscopic and single-crystal X-ray techniques. The spectroscopic analyses of the complex indicated a symmetrical bidentate coordination of the dithio ligand through the S-atoms. The single-crystal X-ray structure revealed a distorted square pyramidal coordinate geometry with S atoms around the Zn ion. The optical properties and the morphology of the as-prepared nanoparticles were studied by UV-Vis and photoluminescense spectroscopy, and transmission electron microscopy (TEM), respectively. HDA-ZnS are spherical and monodispersed with an average size of 4.5?nm, as estimated from the optical absorption spectrum and the TEM image. The ZnS nanoparticles obtained via pyrolysis in a furnace yielded the hexagonal wurtzite phase, whereas the HDA-ZnS nanoparticles showed a mixture of wurtzite and cubic phase with the cubic phase being dominant. 相似文献
205.
《Ceramics International》2021,47(18):25249-25254
Glasses of the composition Li2SO4–MgO–P2O5 mixed with varied contents (0.2–1.0 mol%) of nickel oxide were synthesized. Various spectroscopic investigations have indicated gradual growing proportions of Oh Ni2+ ions in the host glass. IR spectral results, in particular, have clearly demonstrated an increased degree of structural disorder of the glass nerwork with increased content of NiO. The intensity of third harmonic generation (THG) component of probing beam viz., Nd:YAG laser (λ = 1064 nm and power density J = 0–200 J/m2) induced due to the interaction of inherent dipoles with the incident laser beam, exhibited an increasing trend with increase of nickel oxide concentration up to 0.8 mol%. Analysis of the results of these studies indicated that Li2SO4–MgO–P2O5 glass samples doped with optimal content of NiO (~ 0.8 mol%) are more favorable for achieving intense THG beam with low phonon losses. Hence, such glasses may be considered as useful for optoelectronic devices. On the other hand, the samples doped with NiO content greater than 0.8 mol%, the Ni2+ ions seemed to prefer (revealed by optical absorption and IR spectroscopy studies) tetrahedral occupancy in the glass matrix and enhance the degree of the polymerization of the glass matrix; such increased order of polymerization of the glass matrix appears to be a hindrance for accomplishing higher intensity of THG signal due to large phonon losses. These results were found to be in concurrence with the inferences from other studies that include electrical properties, positron annihilation lifetime (PAL) spectroscopy and mechanical properties. 相似文献
206.
《Ceramics International》2021,47(22):31294-31301
The solid solution of Pb1-x Sm2x/3 (Zr0.6 Ti0.4) O3 ceramics with x = 0.1, 0.2, 0.3, and 0.4 was prepared via the high-energy ball milling technique. Further, the effect of excessive Sm2O3 substitution at Pb-site on structural, dielectric, and dc-conductivity properties was studied. The X-ray diffraction (XRD) analysis confirmed that all samples were crystallized with perovskite and pyrochlore diphase form. Excess Sm3+ substitution in the PZT system increases the pyrochlore volume fraction from 5 to 20% and induces a structural phase transition from rhombohedral to a tetragonal structure. The microstructural study by TEM and SEM indicated that the particles were spherical with an average size of 43–55 nm. The frequency and temperature-dependent dielectric constant for all compositions was carried out and it is obtained that the dielectric constant decreases with Sm3+ content. The phase transition temperature first decreases up to x = 0.2 and then increases for the higher concentration of samarium. The dc-conductivity studies revealed that all samples showed an unusual mixed TCR effect (both positive and negative temperature coefficient of resistance). Such properties of the studied samples indicate that the material is suitable for potential applications in thermistors, and temperature sensors of the automotive, and petroleum industries. 相似文献
207.
208.
Serkan Öztürk Ayhan Yıldırım Mehmet Çetin Mustafa Tavaslı 《Journal of surfactants and detergents》2014,17(3):471-481
New cationic surfactants were synthesized by the quaternization of a number of straight-chain amide derivatives with triethylamine or pyridine. The corrosion inhibition tests of the surface-active compounds were performed at room temperature for 24 h on carbon steel coupons in acidic media using the gravimetric method. The acidic media used were 1.5 M HCl and 1.5 M H2SO4. Almost all of the synthesized cationic surfactants showed efficient inhibition of corrosion in the test. To establish the inhibition efficiencies of the inhibitors, surface characterization studies (contact angle measurements, SEM analysis and optical profilometer images) of the metal coupons used were performed. 相似文献
209.
Girija Bheemaneni 《国际聚合物材料杂志》2019,68(1-3):119-125
AbstractPBAT/PMMA/MA/TCP composites were prepared by melt blending and characterized by FTIR, XRD, SEM and in vitro bioactivity studies using SBF and cell viability tests. SBF studies revealed good bioactivity nature which was observed in SEM and confirmed by EDAX. Cell viability test revealed an excellent viability of squamous cells within 2?h than the control. Soil burial tests of the composites show fast degradation within 50 days under natural conditions. The tensile and hardness properties is marginally increased than that of PBAT/PMMA blend. These biocomposites can be used for the fabrication of medical devices by melt blending and injection molding process. 相似文献
210.
Synthesis,Pharmacological Evaluation,and Docking Studies of Novel Pyridazinone‐Based Cannabinoid Receptor Type 2 Ligands 下载免费PDF全文
Dr. Giulio Ragusa Dr. Serena Bencivenni Dr. Paula Morales Dr. Tyra Callaway Dr. Dow P. Hurst Dr. Battistina Asproni Dr. Stefania Merighi Dr. Giovanni Loriga Prof. Gerard A. Pinna Prof. Patricia H. Reggio Prof. Stefania Gessi Prof. Gabriele Murineddu 《ChemMedChem》2018,13(11):1102-1114
In recent years, cannabinoid type 2 receptors (CB2R) have emerged as promising therapeutic targets in a wide variety of diseases. Selective ligands of CB2R are devoid of the psychoactive effects typically observed for CB1R ligands. Based on our recent studies on a class of pyridazinone 4‐carboxamides, further structural modifications of the pyridazinone core were made to better investigate the structure–activity relationships for this promising scaffold with the aim to develop potent CB2R ligands. In binding assays, two of the new synthesized compounds [6‐(3,4‐dichlorophenyl)‐2‐(4‐fluorobenzyl)‐cis‐N‐(4‐methylcyclohexyl)‐3‐oxo‐2,3‐dihydropyridazine‐4‐carboxamide ( 2 ) and 6‐(4‐chloro‐3‐methylphenyl)‐cis‐N‐(4‐methylcyclohexyl)‐3‐oxo‐2‐pentyl‐2,3‐dihydropyridazine‐4‐carboxamide ( 22 )] showed high CB2R affinity, with Ki values of 2.1 and 1.6 nm , respectively. In addition, functional assays of these compounds and other new active related derivatives revealed their pharmacological profiles as CB2R inverse agonists. Compound 22 displayed the highest CB2R selectivity and potency, presenting a favorable in silico pharmacokinetic profile. Furthermore, a molecular modeling study revealed how 22 produces inverse agonism through blocking the movement of the toggle‐switch residue, W6.48. 相似文献