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Chinese Physics B 2010年第2期19卷 77-91页

作者： Gamal G.L.Nashed Centre for Theoretical Physics The British University in EgyptEl-Sherouk CityMisr-Ismalia Desert Road Postal No.11837P.O.Box 43Egypt Mathematics Department Faculty of ScienceAin Shams UniversityCairoEgypt

The energy--momentum tensor, which is coordinate-independent, is used to calculate energy, momentum and angular momentum of two different tetrad fields. Although, the two tetrad fields reproduce the same space--time their energies are different. Therefore, a regularized expression of the gravitational energy--momentum tensor of the teleparallel equivalent of general relativity （TEGR）, is used to make the energies of the two tetrad fields equal. The definition of the gravitational energy--momentum is used to investigate the energy within the external event horizon. The components of angular momentum associated with these space--times are calculated. In spite of using a static space--time, we get a non-zero component of angular momentum! Therefore, we derive the Killing vectors associated with these space--times using the definition of the Lie derivative of a second rank tensor in the framework of the TEGR to make the picture more clear.

关键词： teleparallel equivalent of general relativity brane world black holes gravitational energy--momentum tensor regularized expression of the gravitational energy--momentum

A Study of China's Cultural Image Building in the Emerging Media Context

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学术界 2016年第2期 281-286页

作者： Li Nan faculty of International studies Henan Normal University Xinxiang Henan 453007

In the context of emerging media,cultural image has been widely studied form the perspectives of culture,media and language,especially after the introduction of the concept of cultural *** paper investigates the forms and contents of the emerging media involved in China' s cultural image building,and the interaction on cultural issues between audiences home and *** China's cultural image has been analyzed into the technical,formal,and informal levels based on Hall's *** analysis shows more in-depth,effective and prompt use of the emerging media may help improve China' s cultural image building.

关键词：中国文化形象塑造媒体语境文化形象文化问题

Preparation and characterization of (CeO2)x-(Fe2O3)1-x nanocomposites:reduction kinetics and hydrogen storage

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Rare Metals 2020年第3期39卷 218-229页

作者： Shimaa G.Sayed Waleed M.A.El Rouby Ahmed A.Farghali Materials Science and Nanotechnology Department Faculty of Postgraduate Studies for Advanced Science(PSAS)Beni-Suef UniversityBeni Suef62511Egypt

A series of nanosized CeO2-Fe2O3 mixed-oxide nanocomposites with different Ce4+/Fe3+molar ratios were successfully prepared by a co-precipitation *** surface area increased with Fe2O3 content increasing up to 60 wt%in the ***,with further increase in Fe2O3 content,the surface area began to *** reduction processes of the CeO2-Fe2O3 nanocomposites were studied in a hydrogen atmosphere at 300-600℃.The reduction rates increased by increasing both the temperature and Fe2O3 content in the *** microstructure of the reduced composites at 500℃illustrated the presence of a considerable number of macro-and *** activation energy values were calculated which were in the range of 3.56-5.37 kJ mol-1 at the initial stages(up to 35%reduction)and 5.21-10.2 kJ·mol-1 at the final stages(up to 80%reduction)of *** rate-controlling mechanisms in both the initial and final reduction stages were determined,and the initial reaction stage was controlled by combined gaseous diffusion and interfacial chemical reaction mechanisms for all the composites except for pure CeO2,which was controlled by a chemical reaction *** final reaction stage was controlled by a gaseous diffusion mechanism for some composites,while for the others it was controlled by combined gaseous diffusion and interfacial chemical reaction *** hydrogen sorption properties of the nanocomposites were studied by pressure composition isotherms using a volumetric *** storage in the nanocomposites increased by increasing the temperature because of the formation of oxygen vacancies which enhance atomic H adsorption and function as strong adsorption sites forming more metal hydride covalent bonds.

关键词： CeO2-Fe2O3 nanocomposite Reduction kinetics Reduction mechanism Hydrogen storage Oxygen vacancies

Cultural Intervention in English and Chinese Translation

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现代外语 2002年第3期25卷 299-303页

作者： ZHING Wei-he faculty of English Language and Culture Guangdong U of Foreign studies

In this paper, the author defines translation as an act of communication in a cross-cultural context, the main aim of which is to establish communication between members of different cultures in accordance with previously determined communicative target purpose. He then discusses the unavoidable cultural intervention in the process of translation. Cases in aesthetic preference, political involvement and ethical tradition are studied to prove his proposition that translation is not only linguistic transfer, but also cultural transfer, and that 搕he more inclusive the target culture is, the closer the translation is to the source culture, the more exclusive the target culture is, the closer the translation must be to the target culture.?In the last part of the paper, he proposes strategies of translation (especially for the translation between English and Chinese) with which we can tackle the cultural barriers in the process of translation, i.e. distortion, ignoring and coinage.

关键词：英语汉语翻译学文化差异翻译技巧

Energy Efficiency of a Solar Green Building Using Bio-Sourced Materials for Indoor Temperature and Humidity Optimization

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Energy Engineering 2025年第1期122卷 41-62页

作者： SoumiaMounir Youssef Maaloufa Abdelhamid Khabbazi ElinaMohd Husini Nurul SyalaAbdul Latip YakubuAminuDodo Rime ELHarrouni MinaAmazal Asma Souidi Malika Atigui Ahmed Aharoune National School of Architecture Agadir New Complex Ibn ZohrAgadirBP 20732Morocco EMDD CERNE2DUniversity of Mohammed V in RabatEst SaleSaleBP 227Morocco Thermodynamics and Energetics Laboratory Faculty of ScienceIbn Zohr UniversityAgadirBP 8106Morocco faculty of Built Environment University Sains Islam MalaysiaNilaiBP 71800Malaysia Architectural Engineering Department Najran UniversityNajranBP 1988Saudi Arabia The Centre of Scientific and Engineering Research Najran UniversityNajranBP 1988Saudi Arabia Euro-Mediterranean School of Architecture Design and UrbanismEuro-Mediterranean University of FezFezBP 51Morocco

A clean environment with low carbon emissions is the goal of research on the development of green and sustainable buildings that use bio-sourced materials in conjunction with solar energy to create more sustainable *** is particularly true in Africa,where there aren’t many studies on the *** current study suggests a 90 m^(2) model of a sustainable building in a dry climate that is movable to address the issue of housing in remote areas,ensures comfort in harsh weather conditions,uses solar renewable resources—which are plentiful in Africa—uses biosourced materials,and examines how these materials relate to temperature and humidity control while emitting minimal carbon *** order to solve the topic under consideration,the work is split into two sections:numerical and experimental *** TRNSYS and Revit,the suggested prototype building is examined numerically to examine the impact of orientation,envelope composition made of bio-sourced materials,and carbon *** a hygrothermal investigation,experiments are conducted to evaluate this prototype’s ***,an examination of the photovoltaic system’s production,consumption,and several scenarios used tomaximize battery life is included in the *** the biosourcedmaterial achieves a thermal transmittance of 0.15(W.m^(-2).K^(-1)),the results demonstrate an intriguing finding in terms of *** value satisfies the requirements of passive building,energy autonomy of the dwelling,and injection in-network with an annual value of 15,757 ***,compared to the literature,the heating needs ratio is 6.38(kWh/m^(2).an)and the cooling needs ratio is 49(kWh/m^(2).an),both of which are good *** to international norms,the inside temperature doesn’t go above 26℃,and the humidity level is within a comfortable range.

关键词： Bio-sourced materials energy sustainability green architecture built environment

The role of clinical diagnosis criteria on the frequency of accommodative insufficiency

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International Journal of Ophthalmology(English edition) 2019年第4期12卷 647-653页

作者： María García-Montero Beatriz Antona Ana Rosa Barrio Carmen Nieto-Zayas Irene Martínez-Alberquilla José Luis Hernández-Verdejo Department of Optometry and Vision Faculty of Optics and Optometry Complutense University of Madrid Department of Statistics and Operations Research Ⅲ Faculty of Statistical Studies Complutense University of Madrid

AIM: To estimate and compare the frequency of accommodative insufficiency(AI) within the same clinical population sample depending on the type of clinical criteria used for diagnosis. Comparing the frequency within the same population would help to minimize bias due to sampling or methodological variability. METHODS: Retrospective study of 205 medical records of symptomatic subjects free of any organic cause and symptoms persisting despite optical compensation evaluated. Based on the most commonly clinical diagnostics criteria found in the literature, four diagnostics criteria were established for AI(Ⅰ, Ⅱ, Ⅲ and Ⅳ) based on subjective accommodative tests: monocular accommodative amplitude two or more diopters below Hofstetter's minimum value [15-(0.25×age)](Ⅰ, Ⅱ, Ⅲ, Ⅳ); failing monocular accommodative facility with minus lens, establishing the cut-off in 0 cycles per minute(cpm)(Ⅰ) and in 6 cpm(Ⅱ, Ⅲ); failing binocular accommodative facility with minus lens, establishing the cut-off in 0 cpm(Ⅰ) and in 3 cpm(Ⅱ).RESULTS: The proportion of AI(95%CⅠ) for criteria Ⅰ, Ⅱ, Ⅲ and Ⅳ were 1.95%(0.04%-3.86%), 2.93%(0.31%-4.57%), 6.34%(1.90%-7.85%) and 41.95%(35.14%-48.76%) respectively, with a statistically significant difference shown between these values(χ2=226.7, P<0.001). A pairwise multiple comparison revealed that the proportion of AI detected for criterion Ⅳ was significantly greater than the proportion for the rest of the criteria(P-adjusted<0.05 in all cases).CONCLUSION: The prevalence of cases of AI within the same clinical population varies with the clinical diagnostic criteria selected. The variation is statistically significant when considering the monocular accommodative amplitude as the only clinical diagnostic sign.

关键词： epidemiology amplitude of accommodation accommodative facility

Annual and seasonal changes of the air temperature with altitude in the Upper Dades valley, High Atlas, Morocco

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Journal of Mountain Science 2022年第1期19卷 85-102页

作者： ŻMUDZKA Elwira DŁUŻEWSKI Maciej DĄBSKI Maciej LEZIAK Kamil ROJAN Elżbieta Department of Climatology Faculty of Geography and Regional StudiesUniversity of WarsawKrakowskie Przedmieście 3000-927 WarsawPoland Department of Geomorphology Faculty of Geography and Regional StudiesUniversity of WarsawKrakowskie Przedmieście 3000-927 WarsawPoland

The purpose of this study is to determine the size of air temperature changes with altitude in the mountains of the arid zone, on the example of the Upper Dades valley(High Atlas, Morocco). The air temperature change with altitude was determined on the basis of 5 years data from three meteorological stations. The analysis was carried out on an annual and seasonal basis. The annual and daily variations of thermal gradients between pairs of stations were also determined. It was found that the average thermal gradient in the Upper Dades valley was-1.02℃ per 100 m. The highest values of the thermal gradient occur in winter and the lowest in summer. In winter,the thermal gradient was characterized by the greatest variability. Minima of the daily variation of air temperature gradients were observed in early morning hours and maxima around midday. In the lower part of the valley, air temperature inversion frequently developed between 10 AM and 3 PM *** obtained results show high thermal gradients in the mountains of the arid zone, with their annual amplitude increasing in the lower parts of the *** instantaneous values of the gradients were significantly modified by the supply of latent heat and the occurrence of dust storms. It has been shown that the advection factor plays an important role in shaping large gradient values. The study contains novel results of thermal gradient measurements in high mountains of arid zone.

关键词： Air temperature gradient Thermal inversion Annual and seasonal variability Synoptic situation High mountains of arid zone High Atlas Mountains

Do BRICS Have Similar Disaggregated Trade Patterns with Different Regions?

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2019年第2期14卷 302-328页

作者： Farkhondeh Jabalameli Ehsan Rasoulinezhad faculty of Economics University of TehranTehran ***Iran faculty of World studies University of TehranTehran ***Iran

This is the first study attempting to investigate the patterns of BRICS' imports and exports with five United Nations regional groups: the African, Asia-Pacific, Eastern European, Latin American and Caribbean, and Western European and Others. A panel data gravity trade model with series from 2001 to 2016 was used to estimate the gravity variables in the models. The main results provide evidence that reinforced the dissimilarities in the foreign trade patterns of BRICS with these five regional groups. The econometric results substantiated that BRICS' foreign trade patterns are sensitive to changes in the economies of trading partners from the more developed regions. This is evidence for stronger economic ties between BRICS and the more developed regions such as Western Europe and Asia-Pacific. It also reveals the trade convergence of BRICS in these developed regions.

关键词： BRICS foreign trade pattern disaggregated trade data gravity model

Structural and luminescence studies of europium ions in lithium aluminium borophosphate glasses

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Journal of Rare Earths 2014年第7期32卷 585-592页

作者： Poh Sum Wong Ming Hua Wan Rosli Hussin Hendrik O.Lintang Salasiah Endud Phosphor Research Group Department of Physics Faculty of Science Universiti Teknologi Malaysia Ibnu Sina Institute for Fundamental Science studies Universiti Teknologi Malaysia Department of Chemistry Faculty of ScienceUniversiti Teknologi Malaysia

Eu3＋ doped borophosphate glasses with the chemical composition 20Li2O-30Al2O3-10B2O3-40P2O5-xEu2O3（where x=0.05 mol.%, 0.1 mol.%, 1.0 mol.%, 1.5 mol.% and 2.0 mol.%） were prepared by conventional melt quenching technique. The structural and luminescence properties of the prepared Eu3＋ doped borophosphate glasses were studied and compared with reported results. The XRD pattern showed the amorphous nature of the prepared glasses. Whereas, the FTIR spectra revealed the vibrational modes in the prepared glasses. The bonding parameters（ β and ？） were calculated through the excitation spectra. Judd-Ofelt（J-O） intensity parameters were calculated from the emission spectra and were used to determine transition probability（A）, stimulated emission cross-section（σE P）, radiative lifetime（τR） and branching ratios（βexp） for the transition 5D0→7Fj（j=1, 2, 3 and 4） of Eu3＋ ions. Furthermore, the luminescence intensity ratio（R） of 5D0→7F2 to 5D0→7F1 transition was also calculated. Transition 5D0→7F2 had the highest value of stimulated emission cross-section and branching ratios and the results were comparable with the reported values. This indicated that the present glass is promising host material for Eu3＋ doped fiber amplifiers.

关键词： europium ions luminescence properties borophosphate glasses Judd^Ofelt analysis decay time rare earths

THE　CAUSES　AND　DEVELOPMENTAL　TREND　OF　desertIFICATION　IN　THE　MIDDLE　REACHES　OF　THE　YARLUNG　ZANGBO　RIVER　AND　ITS　TWO　TRIBUTARIES　IN　XIZANG

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Chinese Geographical Science 1995年第4期5卷 355-364页

作者：董光荣董玉祥李森金炯靳鹤龄刘玉璋 Institute of desert Research the Chinese Academy of Sciences Lanzhou PRC

The middle reaches of the Yarlung Zangbo River and its two tributaries are an important development and construction region in Xizang(Tibet) in recent years, but the fast development of desertification has caused immense damages to its social and economic development, so the study on desertification in this region is significant. The paper studies the causes and development trend of desertification in this region through analysis of natural and human factors as well as their relationship. It can be concluded that desertification in the study area is one process which is accelerated and intensified by human activities on the basis of the slow natural desertification process. It is resulted from the dislocation of irrational and intensive human activities, fragile eec-environment and meagre natural resources, and tends to become more wide and severe.

关键词： desertification eco-environment the Yarlung Zangbo River Xizang