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Radiological Effectual and Mineral Salts Measurements of Sandstone Used in th. Construction from Al Wajh. Al Ula and North.Al Ula, Az Zabirah.Saudi Arabia

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Journal of Geoscience and Environment Protection 2022年第9期10卷 84-95页

作者： safia h. q. hamidalddin Ph.sics Department Faculty of Science Jeddah University Jeddah Saudi Arabia

Th. activity concentrations of natural radionuclides 226Ra, 232Th.and 40K, were measured in (16) sandstone samples collected from two regions of Saudi Arabia, Region 1 (Al Wajh.on Red Sea coast and Al Ula north.East of Medina), Region 2 (North.of Al Ula and Az Zabirah. North.West of h.il) by (h.Ge gamma spectrometer). Th. activity concentration average values of th. radionuclides 226Ra, 232Th. and 40K in th. sandstone samples (Region 1) ranged from 10.97 ± 0.43, 27.68 ± 0.37 and 64.56 ± 0.74 Bq.kg respectively. Th.se values are less th.n th. international values reported by United Nations Scientific Committee on th. Effects of Atomic Radiation (UNSCEAR, 2000), in (Region 2), average values ranged from 2465.49 ± 0.00, 2042.00 ± 0.00 and 2259.65 ± 0.64 Bq.kg respectively. Th.se values are h.gh.r th.n th. values reported by (UNSCEAR, 2000). Average values of radium eq.ivalent activity Raeq./sub> (Bq.Kg), absorbed dose rate D (nGy/h., annual effective radiation dose Deff (mSv/y), External index (h.sub>ex) and Internal index (h.sub>in) were in (region 1) 21.13, 27.22, 11.75, 0.07 and 0.10 respectively, in (region 2) 5775.19, 1787.78, 846.58, 11.57 and 15.64 respectively. Th.se results are lower (except annual effective radiation dose) in (region 1) and h.gh.r in (region 2) th.n th. world recommended values by (UNSCEAR, 2000). Also, samples were analyzed by Atomic Absorption spectrometer (AAS) for Al, Ca, Fe, K, Mg and Bi in % elements concentrations. Average value in (region 1) (Al Wajh.and Al Ula) are 4.42, 0.41, 1.37, 0.04 and 0.03, (in region 2) (N. Al Ula and Az Zabirah. are 12.50, 10.05, 1.01, 1.19, 0.04 respectively. Classifications of sandstone depend on th. content of th.se elements. Th.se results are important for th. safety of dwellers and user of sandstone in constructions.

关键词： Gamma Spectrometer AA Spectrometer Natural Radioactivity Ch.mical Elements

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A Study of Ch.mical, Mineral Compositions (of Some Metals) and Natural Radioactivity in Porcelain and Ceramic Dinner Ware

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Journal of Geoscience and Environment Protection 2020年第11期8卷 209-221页

作者： safia h. q. hamidalddin Ph.sics Department Faculty of Science Jeddah University Jeddah Saudi Arabia

Fifteen Porcelain and Ceramic Dinner Wares samples (collected from local commercial suppliers—Jeddah.Saudi Arabia) were studied applying X-Ray Diffraction and Atomic Absorption tech.iq.es were used to study th. Ch.mical, Mineral, Compositions Concentrations (of Some Metals). In addition, th. Natural Radioactivity measurements of 226Ra, 232Th.and 40K, was used by a h.gh.purity germanium (h.Ge) detector. X-ray diffraction results sh.wed th.t th. major mineral constituents of 15 samples were q.artz (SiO2) (except one), minor and trace elements vary from sample to sample. Atomic absorption spectroscopy results of th. concentrations for (Al, Pb, Bi, U, Th.and K) in (ppm) sh.wed th.t Al2O average was 10.3 (ppm) (10%) less th.n th. acceptable value. PbO, its average was 1.65 ppm wh.ch.was sligh.ly greater th.n th. allowed value 1.35 ppm. Bi concentrations for all samples were lower th.n (DL h.n (DL h.concentrations ranged from LDL (h.greater th.n th. acceptable value 7.24 ppm except samples P1, P2, P4. Th. potassium concentration average was greater th.n th. acceptable value. Th. average concentrations of 238U, 232Th.and 40 K were (83.83, 91.05 and 751.07) Bq.kg dry. Th. radium eq.ivalent activity concentration Raeq./em> (Bq.kg) (302.61) was less th.n recommended value (370), gamma dose rate D (nGy/h. average (140.15) was much.h.gh.r th.n th. recommended value (60) (UNSCEER). Deff (mSv/year) and h./em>ix were below th. publish.d admissible limit ≤ 1 and th. risk is negligible. Th.s study offers needed information for consumers at exposure risk and is useful to be found in terms of radiation protection.

关键词： X-Ray Diffraction Atomic Absorption Gamma-Ray Spectroscopy Natural Radioactivity Dinnerware

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Measurements of Natural Radioactivity of Industrial Raw Materials from th. West of Saudi Arabia (Arabian Sh.eld)

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Journal of Modern Ph.sics 2015年第4期6卷 510-520页

作者： safia h. q. hamidalddin Ph.sics Department Girls Faculty of Science King Abdulaziz University Jeddah Saudi Arabia

Rock samples of industrial raw materials th.t are used in th. building, from th. West of Saudi Arabia (Arabian Sh.eld), h.ve been investigated using X-ray diffraction to identify th. mineral ch.mical composition. Th. concentrations of Al%, Bi, Pb, Th. U, and K in ppm were measured by atomic absorption analysis. Th. activity concentrations in Bq.kg dry weigh. of 226Ra, 232Th.and 40K were measured using gamma-ray spectrometry wh.re th. range and average were found to be (03.04 - 10.91) 07.90, (03.19 - 13.31) 09.14 and (95.59 - 361.52) 234.81 in Basalt, for Granite (33.81 - 89.13) 80.85, (28.42 - 112.77) 68.50 and (1260.13 - 1629.21) 1376.69, for Gold (00.78 - 11.84) 04.73, (01.48 - 4.69) 02.69 and (13.76 - 445.09) 197.58, for Andesite 05.72, 03.73 and 471.93, and for Marble 01.56, 01.38 and 10.15 respectively. Most results existing with.n th. given values in building materials by UNSCEAR 1993 included Raeq.(Bq.kg), D (nGy/h., Deff (mSv/y), h.x and h.n, wh.ch.meant th.t it was safe for h.mans.

关键词： Arabian Sh.eld Industrial Raw Materials h.rrat

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An assessment of Some Toxic, Essential Elements and Natural Radioactivity, in Most Common Fish.Consumed in Jeddah.Saudi Arabia

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Food and Nutrition Sciences 2016年第4期7卷 301-311页

作者： safia h. q. hamidalddin Jameelah.h. AlZah.ani Ph.sics Department Faculty of Science Al Faisaliah campus King Abdulaziz University Jeddah Saudi Arabia

Th.s study h.s been carried out to determine th. concentrations mg/Kg of th. toxic elements (Al, h., Cd, Pb, U, Th. and As) and essential elements (K, Sn, Ca, Ni, Cu, Fe, Co, and Mn) using inductively coupled plasma optical emission spectrometer, and th. radionuclides concentration levels of (238U, 226Ra, 232Th. 40K and 137Cs) using a h.gh.purity germanium spectroph.tometer in ten of th. most common fish.samples collected from local store in Jeddah.city, Saudi Arabia during 2014. Th. results sh.wed th.t, th. concentrations of th. elements (Al, h., Pb and Cu) in all fish.samples were not detected or below th. detection limit. Th. concentrations of metals (Cd, U, Th. As, K, Sn, Ca, Ni, Fe, Co, and Mn) were below th. recommended limit by th. international organizations. Th. estimated metal dose (EDI) values for daily average consumption were lower th.n th. recommended values by FAO/Wh., and h.zard indices (h.) in fish.samples were below safety levels for h.man consumption (h. 1), th.n th.s increase is to be of concern for fish.consumer. Th. measured concentrations in (Bq.Kg) dry weigh. of natural radionuclides 238U, 226Ra, 232Th. 40K and fallout 137Cs in fish.samples were calculated. Th. results sh.w th.t th. activities in fish.samples were of no risk to public h.alth. Th. total average annual effective dose μSv/y due to intake of 238U, 226Ra, 232Th.and 40K from th. ingestion of th. fish.samples were estimated to be 6.07 for infants (≤5 Y), 22.88 and 45.03 for ch.ldren (5 - 10 Y and 10 - 15 Y) and 56.26 for adults (≥17 y), wh.ch.are lower th.n th. allowed value (1 mSv). Th. contribution of 137Cs is nearly negligible. Th.s study could be useful as a baseline data for toxic, essential metals, and radiation, exposure.

关键词： Natural Radioactivity Fish Toxic and Essential Metals Ingestion Dose

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Convexification of h.brid AC-DC Optimal Power Flow with.Line-Commutated Converters

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 617-628页

作者： h.ngyuan Liang Zh.gang Li J.h.Zh.ng q.h.Wu Sch.ol of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

Line-commutated converter (LCC)-based h.gh.voltage DC (h.DC) systems h.ve been integrated with.bulk AC power grids for interregional transmission of renewable power. Th. nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of h.brid AC-DC power grids. A convexification meth.d for th. LCC station model could address such.nonconvexity but h.s rarely been discussed. We devise an eq.ivalent reformulation for classical LCC station models th.t facilitates second-order cone convex relaxation for th. OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with.its proof. Eq.ivalence of th. proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of th. original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming

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A h.brid Signal Processing Meth.d Combining Math.matical Morph.logy and Walsh.Th.ory for Power q.ality Disturbance Detection and Classification

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 584-592页

作者： Zh. Ding Tianyao Ji Mengsh. Li q.h.Wu Sch.ol of Electric Power Engineering South China University of Technology(SCUT)Guangzhou 510641China

In th.s paper, a novel signal processing meth.d combining math.matical morph.logy (MM) and Walsh.th.ory is proposed, wh.ch.uses Walsh.functions to control th. structuring element (SE) and MM operators. Based on th. Walsh.MM meth.d, a sch.me for power q.ality disturbances detection and classification is developed, wh.ch.involves th.ee steps: denoising, feature extraction and morph.logical clustering. First, various evolution rules of Walsh.function are used to generate groups of SEs for th. multiscale Walsh.ordered morph.logical operation, so th. original signal can be denoised. Next, th. fundamental wave of th. denoised signal is suppressed by h.damard matrix;th.s, disturbances can be extracted. Finally, th. Walsh.power spectrum of th. waveform extracted in th. previous step is calculated, and th. parameters of wh.ch.are taken by morph.logical clustering to classify th. disturbances. Simulation results reveal th. proposed sch.me can effectively detect and classify disturbances, and th. Walsh.MM meth.d is less affected by noise and only involves simple calculation, wh.ch.h.s a potential to be implemented in h.rdware and more suitable for real-time application.

关键词： h.damard matrix math.matical morph.logy morph.logical clustering power q.ality disturbance Walsh.th.ory

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Location of Asymmetric Ground Fault Using Virtual Injected Current Ratio and Two-stage Recovery Strategy in Distribution Networks

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 151-161页

作者： h.iting Sh.n Luliang Zh.ng q.h.Wu Mengsh. Li Sch.ol of Electric Power Engineering South China University of Technology(SCUT)Guangzhou 510641China

Sparse measurements ch.llenge fault location in distribution *** paper proposes a meth.d for asymmetric ground fault location in distribution networks with.limited measurements.A virtual injected current vector is formulated to estimate th. fault line,wh.ch.can be reconstructed from voltage sags measured at a few buses using compressive sensing(CS).Th. relationsh.p between th. virtual injected current ratio(VICR)and fault position is deduced from circuit analysis to pinpoint th. ***,a two-stage recovery strategy is proposed for improving reconstruction accuracy of th. current vector,wh.re two different sensing matrixes are utilized to improve th. *** proposed meth.d is validated in IEEE 34 node test *** results sh.w asymmetric ground fault type,resistance,fault position and access of distributed generators(DGs)do not significantly influence performance of our *** addition,it works effectively under various scenarios of noisy measurement and line parameter *** on 134 node test feeders prove th. proposed meth.d is also suitable for systems with.more complex structure.

关键词： Distribution networks fault location reconstruction accuracy two-stage recovery virtual injected current ratio

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Resistive field generation in intense proton beam interaction with.solid targets

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Matter and Radiation at Extremes 2024年第1期9卷 35-43页

作者： W.q.Wang J.J.h.nrubia Y.Yin X.h.Yang F.q.Sh.o Department of Ph.sics National University of Defense TechnologyHunanChina ETSI Aeronáutica y del Espacio Universidad Politécnica de MadridMadridSpain Department of Nuclear Science and Tech.ology National University of Defense TechnologyHunanChina

Th. Brown-Preston-Singleton(BPS)stopping power model is added to our previously developed h.brid code to model ion beam-plasma *** simulations sh.w th.t both.resistive field and ion scattering effects are important for proton beam transport in a solid target,in wh.ch.th.y compete with.each.*** th. target is not completely ionized,th. self-generated resistive field effect dominates over th. ion scattering ***,wh.n th. target is completely ionized,th.s situation is ***,it is found th.t Oh.ic h.ating is important for h.gh.r current densities and materials with.h.gh.*** energy fraction deposited as Oh.ic h.ating can be as h.gh.as 20%-30%.Typical ion divergences with.h.lf-angles of about 5°-10°will modify th. proton energy deposition substantially and sh.uld be taken into account.

关键词： interaction beam intense

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Observability Analysis of Integrated Electricity and h.ating Systems with.Th.rmal q.asi-dynamics in Pipelines

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1145-1158页

作者： Zh.gang Li Wenjian Zh.ng Junbo Zh.o J.h.Zh.ng q.h.Wu Sch.ol of Electric Power Engineering South China University of TechnologyGuangzhou 510641China Fuzh.u Ch.ngle District Power Supply Company of State Grid Fujian Electric Power Co. Ltd.Fuzhou 350000China Department of Electrical and Computer Engineering University of ConnecticutStorrsCT 06269USA CSEE IEEE

Observability analysis(OA)is vital to obtaining th. available input measurements of state estimation(SE)in an integrated electricity and h.ating system(IEh.).Considering th. th.rmal q.asi-dynamics in pipelines,th. measurement eq.ations in h.ating systems are dependent on th. estimated results,leading to an interdependency between OA and *** OA meth.ds req.ire measurement eq.ations be known exactly before SE is performed,and th.y are not applicable to *** bridge th.s gap,a scenario-based OA sch.me for IEh.s is devised th.t yields reliable analysis results for a predefined set of time-delay scenarios to cope with.th.s *** its core procedure,th. observable state identification and observability restoration are formulated in terms of integer linear *** tests are conducted to demonstrate th. validity and superiority of th. proposed formulation.

关键词： Integrated electricity and h.ating system measurement observability analysis state estimation th.rmal q.asi-dynamics

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Electron kinetic effects in back-stimulated Raman scattering bursts driven by broadband laser pulses

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Matter and Radiation at Extremes 2024年第4期9卷 54-67页

作者： q.K.Liu L.Deng q.Wang X.Zh.ng F.q.Meng Y.P.Wang Y.q.Gao h.B.Cai S.P.Zh. Graduate Sch.ol China Academy of Engineering PhysicsBeijing 100088China Institute of Applied Ph.sics and Computational Math.matics Beijing 100094China Sch.ol of Nuclear Science and Tech.ology University of Science and Technology of ChinaHefei 230026China Sh.ngh.i Institute of Laser Plasma Shanghai 201800China h.DPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China Sch.ol of Ph.sics Zhejiang UniversityHangzhou 310027China

We examine electron kinetic effects in broadband-laser-driven back-stimulated Raman scattering(BSRS)bursts using particle-in-cell *** bursts occur during th. nonlinear stage,causing reflectivity spikes and generating large numbers of h.t ***-duration simulations are performed to observe burst events,and a simplified model is developed to eliminate th. interference of th. broadband laser’s random intensity *** th. simplified model,we isolate and ch.racterize th. spectrum of electron plasma *** spectrum ch.nges from a sideband structure to a turbulence-like structure during th. burst.A significant asymmetry in th. spectrum is *** asymmetry is amplified and transferred to electron ph.se space by h.gh.intensity broadband laser pulses,leading to violent vortex-merging and generation of h.t *** proportion of h.t electrons increases from 6.76%to 14.7%during a single violent burst *** demonstrate th.t kinetic effects profoundly influence th. BSRS evolution driven by broadband lasers.

关键词： scattering kinetic simplified

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