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High Quality of Piezoelectric Response of Nano Ni Doped Pb_1-xNi_xTiO₃ Ceramic

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Journal of Applied Mathematics and physics 2016年第10期4卷 1879-1888页

作者： A. Tawfik O. M. Hemeda D. M. Hemeda M. Barakat M. M. El-Shahawy R. Shady department physics Faculty of Science Tanta University Tanta Egypt department physics Oklat Al-Skoor College of Science & Arts Qassim University Qassim Kingdom of Saudi Arabia

A series of Pb1-xNixTiO3 (x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5) were prepared by the general ceramic and co-precipitation method. The grain size decreased with increasing Ni contents. The piezoelectric modulus d33 increased with increasing Ni contents. It was observed also the d33 of the nanocomposite Pb1-xNixTiO3 prepared by co-precipitation method is higher than those of the prepared by general ceramic method. The coupling fac.or kp increased by the more doping of Ni. The ultrasonic wave velocity decreased also with increasing Ni contents. The polarized nano-sample of composition Pb0.5Ni0.5TiO3 is suitable for improving application of useful piezoelectric technology.

关键词： Piezoelectric Ceramics d33 Coefficient Electromechanical Coupling fac.or Kp

Extreme ultraviolet and x-ray transition wavelengths in Rb XXIV

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Chinese physics B 2015年第10期24卷 115-126页

作者： Indu Khatri Arun Goyal Sunny Aggarwal A.K.Singh Man Mohan department of physics and Astrophysics University of Delhi department of physics Shyamlal CollegeUniversity of Delhi department of physics D.D.U.CollegeUniversity of Delhi

Energy levels, radiative rates, oscillator strengths and line strengths are reported for transitions among the lowest 97 levels of the（1s22s22p6） 3s23p2, 3s23p3 d, 3s3p3, 3p4, 3s3p23 d, and 3s23d2 configurations of Rb XXIV. A multiconfiguration Dirac-Fock（MCDF） method is adopted for the calculations. Radiative rates, oscillator strengths, and line strengths are provided for all electric dipole（E1）, magnetic dipole（M1）, electric quadrupole（E2）, and magnetic quadrupole（M2）transitions from the ground level to all 97 levels, although calculations are performed for a much larger number of *** achieve the accuracy of the data, comparisons are provided with similar data obtained from the Flexible Atomic Code（fac. and also with the available theoretical and experimental results. Our energy levels are found to be accurate to better than 1.2%. Wavelengths calculated are found to lie in EUV（extreme ultraviolet） and x-ray regions. Additionally, lifetimes for all 97 levels are obtained for the first time.

关键词： atomic data energy levels transition probability

Low energy range dielectronic recombination of Fluorine-like Fe^17+at the CSRm

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Chinese physics C 2018年第6期42卷 53-58页

作者： Nadir Khan Zhong-Kui Huang Wei-Qiang Wen Sultan Mahmood Li-Jun Dou Shu-Xing Wang Xin Xu Han-Bing Wang Chong-Yang Chen Xiao-Ya Chuai Xiao-Long Zhu Dong-Mei Zhao Li-Jun Mao Jie Li Da-Yu Yin Jian-Cheng Yang You-Jin Yuan Lin-Fan Zhu Xin-Wen Ma Institute of Modern physics Chinese Academy of Sciences Lanzhou 730000 China University of Chinese Academy of sciences Beijing 100049 China Hefei National Laboratory for Physical sciences at Micro Scale Department of Modern Physics University of Science and Technology of China Hefei 230026 China Shanghai EBIT Laboratory Key Laboratory of Nuclear Physics and Ion-beam Application Institute of Modern Physics Department of Nuclear Science and Technology Fudan University Shanghai 200433 China

The accuracy of dielectronic recombination （DR） data for astrophysics related ions plays a key role in astrophysical plasma modeling. The absolute DR rate coefficient of Fe^17＋ ions was measured at the main cooler storage ring at the Institute of Modern physics, Lanzhou, China. The experimental electron-ion collision energy range covers the first Rydberg series up to n = 24 for the DR resonances associated with the 2p1/2 →^2 p3/2△n= 0 core excitations. A theoretical calculation was performed by using fac.code and compared with the measured DR rate coefficient. Overall reasonable agreement was found between the experimental results and calculations. Moreover, the plasma rate coefficient was deduced from the experimental DR rate coefficient and compared with the available results from the literature. At the low energy range, significant discrepancies were found, and the measured resonances challenge state-of-the-art theory at low collision energies.

关键词： storage ring electron cooler electron-ion recombination plasma rate coefficient

Structural and optical properties of nano-spin coated sol-gel porous TiO_2 films

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Transactions of Nonferrous Metals Society of China 2012年第12期22卷 3003-3011页

作者： M.M.El-NAHASS M.H.alI A.El-DENGLAWEY physics department Faculty of Education Ain Shams University Roxy Cairo 11757 Egypt physics department Faculty of Science Ain Shams University Cairo Egypt physics department Faculty of Science South Valley University Qena 83523 Egypt Phys Dep Fac of Appl Med Sci Turabah 21995 Taif University KSA

Three thicknesses of TiO2 films, 174, 195, and 229 nm, were deposited onto quartz substrates by sol–gel spin coating method. The as-deposited thin films were characterized by nano-crystallite with different sizes (19–46 nm) and relatively high porous structure. Optical constants were determined and showed the lowest refractive index of 1.66 for the as-prepared films that ever reported till now. Obtained results were discussed through current theoretical ideas.

关键词： TiO2 films optical properties nanostructure electron microscopy thin films spin coating technique

Enhancement of electron–ion recombination rates at low energy range in the heavy ion storage ring CSRm

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Chinese physics B 2020年第3期29卷 169-175页

作者： Nadir Khan Zhong-Kui Huang Wei-Qiang Wen Shu-Xing Wang Han-Bing Wang Wan-Lu Ma Xiao-Long Zhu Dong-Mei Zhao Li-Jun Mao Jie Li Xiao-Ming Ma Mei-Tang Tang Da-Yu Yin Wei-Qing Yang Jian-Cheng Yang You-Jin Yuan Lin-Fan Zhu Xin-Wen Ma Institute of Modern physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of sciences Beijing 100049China Hefei National Laboratory for Physical sciences at Micro-scale Department of Modern PhysicsUniversity of Science and Technology of ChinaHefei 230026China

Recombination of Ar^(14+), Ar^(15+), Ca^(16+), and Ni^(19+) ions with electrons has been investigated at low energy range based on the merged-beam method at the main cooler storage ring CSRm in the Institute of Modern physics, Lanzhou,China. For each ion, the absolute recombination rate coefficients have been measured with electron–ion collision energies from 0 meV to 1000 meV which include the radiative recombination(RR) and also dielectronic recombination(DR)processes. In order to interpret the measured results, RR cross sections were obtained from a modified version of the semiclassical Bethe and Salpeter formula for hydrogenic ions. DR cross sections were calculated by a relativistic configuration interaction method using the flexible atomic code(fac. and AUTOSTRUCTURE code in this energy range. The calculated RR + DR rate coefficients show a good agreement with the measured value at the collision energy above 100 ***, large discrepancies have been found at low energy range especially below 10 meV, and the experimental results show a strong enhancement relative to the theoretical RR rate coefficients. For the electron–ion collision energy below 1 meV, it was found that the experimentally observed recombination rates are higher than the theoretically predicted and fitted rates by a fac.or of 1.5 to 3.9. The strong dependence of RR rate coefficient enhancement on the charge state of the ions has been found with the scaling rule of q^(3.0), reproducing the low-energy recombination enhancement effects found in other previous experiments.

关键词： storage ring electron cooler highly charged ions radiative recombination enhancement

Direct Visual Evidence for Neutral and Charged Hexaphyrin Aromaticity with and without Keto-Defect

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Chinese Journal of Chemical physics 2012年第5期25卷 563-570,I0003页

作者： Shan Zhang Peng Song Sha Wang Yu-ling Chu Yuan-zuo Li Zhong Yang Yong Ding Feng-cai Ma department of physics Liaoning UniversityShenyang 110036China Physical and Electronic and Information Engineering Institute Chifeng UniversityChifeng 024001China College of science Northeast Forestry UniversityHarbin 150040China

We use density functional theory and time-dependent together with a set of extensive mul- tidimensional visualization techniques to characterize the influence of keto effect on charge distribution at ground state and electronic transitions for neutral and charged hexaphyrin aromaticity with and without keto-defect. It is found that the aromaticity is the key fac. tor to influence the ground state Mulliken charges distribution properties, other than the meso-aryl-substituted effect. But with the enhancement of the keto-defect, the distribution changes of Mulliken charges on the hexaphyrin groups are larger than those on the pentaflu- orophenyl substituted groups, following with the aromaticity changes from nonaromatic to aromatic. Furthermore, through characterizing by transition density and charge difference density, direct visual evidence for neutral and charged aromaticity with and without keto- defect can be clearly derived, and the ability of charge transfer between units of monoradical （nonaromaticity） and singlet biradical （aromaticity） forms is much stronger than that of neutral forms.

关键词： Aromaticity Keto-defect Porphyrin Charge difference density Transitiondensity

Theoretical study on 2s2p^6np Rydberg states of Cu^(19+)ion

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Chinese physics B 2012年第1期21卷 153-157页

作者： Zhang Zhen-Rong Cheng Xin-Lu Liu Zi-Jiang Yang Jian-Hui Li Hui-Fang Institute of Atomic and Molecular physics Sichuan UniversityChengdu 610065China department of physics Lanzhou City UniversityLanzhou 730070 China

We report on the calculations of transition wavelengths and weighted oscillator strengths for 2s22p^6 2s2p^6np （4 〈 n 〈 20） electric dipole （El） transitions of Cu^19＋ ion. The flexible atomic code （fac. has been adopted for the calculations. Comparisons are made with the experimental data available, showing that the present results for 4 〈 n 〈 6 are more accurate than the previous calculated values. Furthermore, combining the quantum defect theory （QDT） with the transition energies of 2s^22p^62s2p^6np, the quantum defects for 2s2p^6np Rydberg series of Cu^19＋ ion are determined. In addition, the energies of any highly excited states （n 〉 20） for this series can be reliably predicted using the QDT and the given quantum defects. The ionization energies for Cu^19＋ and Cu^20＋ ions are also calculated and they excellently accord with previous experimental and calculated values.

关键词： Cu^19+ion transition wavelength quantum defect quantum defect theory

AEECA for Reliable Communication to Enhance the Network Life Time for WSN

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Intelligent Automation & Soft Computing 2023年第2期35卷 1705-1719页

作者： Ganesh Jayaraman V R Sarma Dhulipala department of Computer science&Engineering Anjalai Ammal Mahalingam Engineering CollegeKovilvenniTamil NaduIndia department of physics Anna UniversityBIT CampusTiruchirappalliTamil NaduIndia

Nowadays,wireless sensor networks play a vital role in our day to day *** communication is preferred for many sensing applications due its convenience,ﬂexibility and *** sensors to sense the environmental fac.or are versatile and send sensed data to central station *** cluster based protocols are provided an optimal solution for enhancing the lifetime of the sensor *** this paper,modiﬁed K-means++algorithm is used to form the cluster and cluster head in an efﬁcient way and the Advanced Energy-Efﬁcient Cluster head selection algorithm(AEECA)is used to calculate the weighted fac.tor of the transmission path and effective data collection using gateway *** experimental results show the proposed algorithm outperforms the existing routing algorithms.

关键词： Wireless sensor network reliable communication energy management energy clustering sensors base station gateway node

Natural Radioactivity Assessment and Radiological Hazards in Soils from Qarun Lake and Wadi El Rayan in Faiyum, Egypt

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Open Journal of Soil science 2013年第7期3卷 289-296页

作者： Saher M. Darwish Samia M. El-Bahi Amany T. Sroor Najat F. Arhoma Nuclear physics Laboratory Ain Shams University Fac- ulty of Girls Heliopolis Cairo Egypt. physics department Faculty of Science Cairo University Giza Egypt physics department Faculty of Science Cairo University Giza Egypt

The activity concentrations of naturally occurring 238U, 232Th and 40K in surfac. soils along Qarun Lake and Wadi El Rayan located in Faiyum, Egypt were determined. The measurements were carried out through gamma-ray spectrometry using a coaxial HPGe detector. The results were compared with those reported in the literature. The radiological hazard radium-equivalent activity index, external and internal indices, radioactivity level index, absorbed dose rate, annual effective dose rate and total absorbed dose rate associated with radioactivity in all samples were evaluated and compared with recommended values. Correlation studies between pairs of radionuclides were performed and discussed.

关键词： Natural Radioactivity Radiological Hazards HPGe Detector Gamma-Ray Spectrometry