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太阳能学报 1993年第1期14卷 77-84页

作者： gheorghe olaru Adriau Radu 罗马尼亚电工研究所布加勒斯特

为了降低风力发电成本,使其具有较好的经济性,应选择最佳的风场和与之匹配的风力机。以安装在罗马尼亚加拉茨(Galati)和苏利纳(Sulina)的10kW和1000kW风力发电机为例进行了分析讨论。

关键词：风力发电风电场风力发动机风轮

Correlation of Microbiological Stability with Redox Processes in White Wines

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Food and Nutrition Sciences 2024年第3期15卷 211-223页

作者： gheorghe Duca Rodica Sturza Natalia Vladei Ecaterina Covaci Research Centre of Physical and Inorganic Chemistry State University of Moldova Chisinau Republic of Moldova Department of Oenology and Chemistry Faculty of Food Technology Technical University of Moldova Chisinau Republic of Moldova

In this paper, the authors analyzed the correlation between the microbiological stability of white wines and the content of sulfur dioxide, which influences the main redox processes that take place in the technological stages of the wine. The consecutive, parallel and spontaneous development of several redox processes and their impact on the quality, microbiological and crystalline stability of white wines were examined. The reduction of additive and subtractive technological interventions, of the amounts of adjuvants (sulphurous anhydride) is essential for the production of organic wines.

关键词： White Wines Acetobacter Sulfur Dioxide Redox Processes Oxygen

Prospective study of hepatitis B and D epidemiology and risk factors in Romania:A 10-year update

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World Journal of Hepatology 2024年第4期16卷 640-649页

作者： Speranta Iacob Liana gheorghe Mirela Onica Laura Huiban Corina Silvia Pop Ciprian Brisc Roxana Sirli Carmen Ester Cristina Mihaela Brisc Sorina Diaconu Ion Rogoveanu Larisa Sandulescu Deiana Vuletici Anca Trifan Department of Gastroenterology Carol Davila University of Medicine and PharmacyBucharest 050474Romania Department of Gastroenterology and Hepatology Fundeni Clinical InstituteBucharest 022328Romania Department of Gastroenterology Grigore T Popa University of Medicine and PharmacyIasi 700115Romania Institute of Gastroenterology and Hepatology Saint Spiridon County HospitalIasi 700111Romania Department of Gastroenterology and Medical Oncology University Emergency Clinical HospitalBucharest 050098Romania Faculty of Medicine and Pharmacy University of OradeaOradea 410087Romania Department of Gastroenterology Emergency County HospitalOradea 410169Romania Center for Advanced Research in Gastroenterology and Hepatology Department of Gastroenterology and Hepatology“Victor Babeş”University of Medicine and PharmacyTimisoara 300041Romania Department of Gastroenterology and Hepatology TimişCounty Emergency Clinical Hospital"Pius Branzeu"Timisoara 300723Romania Department of Internal Medicine II and Gastroenterology University Emergency Clinical HospitalBucharest 050098Romania Department of Gastroenterology University of Medicine and PharmacyCraiova 200349Romania Department of Cardiology Emergency County HospitalCraiova 200642Romania Department of Gastroenterology Research Center of Gastroenterology and HepatologyUniversity of Medicine and PharmacyCraiova 200349Romania Department of Gastroenterology Emergency County HospitalCraiova 200642Romania Department of Gastroenterology Faculty of MedicineGrigore T Popa University of Medicine and PharmacyIasi 700115Romania

BACKGROUND The global burden of hepatitis D virus(HDV)infection represents a major medical challenge and a public health crisis ***,there is a lack of accurate data on the epidemiology and risk factors for *** B virus(HBV)and HDV coinfection causes the most severe form of viral hepatitis,leading to a higher cumulative incidence of liver-related events compared with HBV monoinfection,including the need for liver transplantation and *** To investigate the epidemiology,natural history,risk factors and clinical management of HBV and HDV coinfection in Romanian *** This prospective study was conducted between January and July 2022 in six tertiary gastroenterology and hepatology referral centres in *** consecutive adults admitted for any gastroenterology diagnosis who were HBV-positive were *** with acute hepatitis or incomplete data were *** the 25390 individuals who presented with any type of gastroenterology diagnosis during the study period,963 met the inclusion *** for anti-HDV antibodies and HDV RNA was performed for all *** and risk factor data were collected by investigators using medical charts and patient *** data were stored in an anonymized online database during the *** The prevalence of HBV was 3.8%;among these patients,the prevalence of HBV/HDV coinfection was 33.1%.The median age of the study population was 54.0 years,and it consisted of 55.1%men.A higher prevalence of HBV/HDV coinfection was observed in patients 50–69 years *** with HBV/HDV coinfection were significantly older than those with HBV monoinfection(P=0.03).Multivariate multiple regression analysis identified female gender(P=0.0006),imprisonment(P<0.0001),older age at diagnosis(P=0.01)and sexual contact with persons with known viral hepatitis(P=0.0003)as significant risk factors for *** This study shows that HDV infection among those with HBV re

关键词： Epidemiology Hepatitis B Hepatitis D Natural history Risk factors Romania

Investigations of a nanostructured FeMnSi shape memory alloy produced via severe plastic deformation

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International Journal of Minerals,Metallurgy and Materials 2016年第11期23卷 1315-1322页

作者： gheorghe Gurau Carmela Gurau Vedamanickam Sampath Leandru gheorghe Bujoreanu Faculty of Engineering "Dun?rea de Jos" University of Galati Department of Metallurgical and Materials Engineering Indian Institute of Technology Madras Faculty of Materials Science and Engineering "Gheorghe Asachi" Technical University of Ia?i

Low-cost iron-based shape memory alloys（SMAs） show great potential for engineering applications. The developments of new processing techniques have recently enabled the production of nanocrystalline materials with improved properties. These developments have opened avenues for newer applications for SMAs. The influence of severe plastic deformation induced by the high-speed high-pressure torsion（HSHPT） process on the microstructural evolution of an Fe–Mn–Si–Cr alloy was investigated. Transmission electron microscopic analysis of the alloy revealed the existence of nanoscale grains with an abundance of stacking faults. The high density of dislocations characteristic of severe plastic deformation was not observed in this alloy. X-ray diffraction studies revealed the presence of ε-martensite with an HCP crystal structure and γ-phase with an FCC structure.

关键词： iorn manganese silicon alloys shape memory effect nanostructured materials martensite plastic deformation

Studies on Thermal Contraction of Crankshaft Bearings under Extreme Low Temperatures

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Journal of Thermal Science 2015年第5期24卷 496-501页

作者： Sever-Alexandru Haba gheorghe Oancea Manufacturing Engineering Department Transilvania University of Brasov

This paper presents how the contractions of the main components of a V6 motor with low engine displacement are determined for the cold-start phase under extreme low temperature. Internal combustion engine components have complex geometries and to obtain the thermal contractions, in the research, used the method of finite element analysis. The phenomena of thermal contractions are studied for the cold-start situations at extreme low temperature, knowing that the cold-start phase of an internal combustion engine is the main factor that determines moving rotational and translational parts wear life. Checking the proper choice of clearance is particularly important, as the use of inappropriate values of it leads to rapid operation destruction of the engine group components. The results obtained for the thermal clearances of crankshaft bearings are mathematically modeled and the relations can be used for calculating the clearances. The mathematical models are also useful for implementing in different software tools.

关键词： Engine Engine block Crankshaft bearings Thermal contraction FEA

Spatial modelling of deforestation in Romanian Carpathian Mountains using GIS and Logistic Regression

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Journal of Mountain Science 2019年第5期16卷 1005-1022页

作者： gheorghe KUCSICSA Cristina DUMITRICA Institute of Geography Romanian Academy

Deforestation process represents a wide concern mainly in the mountain environments due to its role in global warming, biodiversity loss, land degradation and natural hazards occurrence. Thus, the present study is focused on the largest afforested landform unit of Romania and, consequently, the most affected area by forest losses: Carpathian Mountains. The main goal of the paper is to examine and analyze the various explanatory variables associated with deforestation process and to model the probability of deforestation using GIS spatial analysis and logistic regression. The forest cover for 1990 and 2012, derived from CORINE Land Cover(CLC) database, were used to quantify historical forest cover change included in the modelling. To explain the biophysical and anthropogenic effects, this study considered several explanatory factors related to local topography, forest cover pattern, accessibility, urban growth and population density. Using ROC(Receiver Operating Characteristic) and 500 controlling sampling points, the statistical and spatial validations were assessed in order to evaluate the performance of the resulted data. The analysis showed that the area experienced a continuous forest cover change, leading to the loss of over 250,000 ha of forested area during the period 1990–2012. The most significant influence of the explanatory factors of deforestation were noticed in case of distance to forest edge(β=–4.215), forest fragmentation(β=2.231), slope declivity(β=–1.901), elevation(β=1.734) and distance to roads(β=–1.713). The statistical and spatial validation indicates a good accuracy of the model with reasonably AUC(0.736) and Kappa(0.739) values. The model's results suggest an intensification of the deforestation process in the area, designing numerous new clusters with high probability in the Apuseni Mountains, northern and central part of the Eastern Carpathians, western part of the Southern Carpathians and northern part of the Banat Mountains. The study cou

关键词： Deforestation probability Romanian Carpathians Logistic Regression

THE MAIN INVARIANTS OF A COMPLEX FINSLER SPACE

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Acta Mathematica Scientia 2014年第4期34卷 995-1011页

作者： Nicoleta ALDEA gheorghe MUNTEANU Department of Mathematics and Informatics Transilvania UniversityIuliu Maniu 50Bra?sov 500091Romania

In this paper we extend the results obtained in [3], where are investigated the general settings of the two-dimensional complex Finsler manifolds, with respect to a local complex Berwahl frame. The geometry of such manifolds is controlled by three real invari- ants which live on T＇M： two horizontal curvature invariants K and W and one vertical curvature invariant I. By means of these invariants are defined both the horizontal and the vertical holomorphic sectional curvatures. The complex Landsberg and Berwald spaces are of particular into, rest. Complex Berwald spaces coincide with K/ihler spaces, in the two - dimensional case, We establish the necessary and sufficient condition under which K is a constant and we obtain a characterization for the Kghler purely Hermitian spaces by the fact K = W=constant and I = 0. For the class of complex Berwald spaces we have K =W = 0. Finally, a classitication of two-dimensional complex Finsler spaces for which the horizontal curvature satisfies a special property is obtained.

关键词： Berwald frame complex Landsberg space complex Berwald space holomorphic sectional curvature

The Role of Viral Infection in Inducing Variability in Virus-Free Progeny in Tomato

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Journal of Integrative Plant Biology 2009年第5期51卷 476-488页

作者： Liliana Marii gheorghe Chiriac Institute of Genetics and Plant Physiology Academy of Sciences of Moldova

The effect of virus-host interactions on subsequent generations is poorly understood. The evaluation of the effects of viral infection on inheritance of quantitative traits in the progeny of infected plants and elucidation of a possible relationship between chiasma frequency in the infected plants and variability of traits in the progeny were investigated. The current study involved genotypes of four intraspecific hybrids of tomato （Solanum lycopersicum L.）, their parental forms and two additional cultivars. Used as infection were the tobacco mosaic virus （TMV） and potato virus X （PVX）. The consequences of the effect of viral infection were evaluated based on chromosome pairing in diakinesis and/or by examining quantitative and qualitative traits in the progeny of the infected tomato plants. Tomato plants infected with TMV ＋ PVX were found to differ in chiasma frequency per pollen mother cell or per bivalent. Deviations have been observed for genotypes of both F1 hybrids and cultivars. At the same time, differences in mean values of the traits under study have only been found for progeny populations （F2-F4） derived from virus-infected F1 hybrids, but not in the case of progeny of the infected cultivars. The rate of recombinants combining traits of both parents increased significantly （2.22-8.24 times） in progeny populations of hybrids infected with TMV＋PVX. The above suggests that the observed effects could be the result of modification of recombination frequencies that can be manifested in heterozygous hybrids and make small contributions to variability in cases of ＇homozygous＇ tomato genotypes （i.e. cultivars）.

关键词： chiasma recombination Solanum lycopersicum traits variability viral infection.

Energy transfer and luminescent properties of Tb^(3+)and Tb^(3+),Yb^(3+)doped CNGG phosphors

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Journal of Rare Earths 2022年第9期40卷 1445-1453,I0004页

作者： S.Hau G.Stanciu D.Avram L.gheorghe C.gheorghe National Institute for Laser Plasma and Radiation PhysicsSolid State Quantum Electronics Laboratory409 Atomistilor StreetP.O.Box MG-36Magurele077125IlfovRomania

In this work,calcium niobium gallium garnet(Ca_(3)Nb_(1.6875)Ga_(3.1875)O_(12)-CNGG)ceramic samples singledoped with Tb^(3+)and co-doped with Tb^(3+)and Yb^(3+)ions were sintered by the solid-state reaction *** structural characterization of the samples was carried out by X-ray diffraction *** optimal concentration of Tb^(3+)ions corresponding to the maximum luminescence in the green spectral range in CNGG:x at%Tb(x=0.1,0.5,1,2,3,4,and 5)was determined to be 4 at%.The timeresolved luminescence of the^(5)D_(4)level(Tb^(3+))in the CNGG:x at%Tb samples was analysed to explore the quenching mechanisms involved in the Tb^(3+)green ***-doped CNGG:4 at%Tb,y at%Yb(y=0.5,2,4,6,8,and 10)ceramics were prepared and *** is shown that CNGG:4 at%Tb,y at%Yb phosphors exhibit intense green luminescence under ultra-violet(UV),visible(VIS),and near-infrared(NIR)excitation,thus demonstrating the presence of simultaneous down-conversion(DC)and upconversion(UC)*** dependence of the UC luminescence intensity on the diode laser pumping power was measured and the results indicate a two-photon process based on cooperative energy transfer(CET).Under UV excitation,the lifetime of the^(5)D_(4)(Tb^(3+))level slowly increases with increase of Yb^(3+)concentration,suggesting the energy transfer from Yb^(3+)to Tb^(3+)ions,while under NIR excitation,the lifetime of the^(5)D_(4)(Tb^(3+))level decreases with increase of Yb^(3+)ions concentration,indicating the presence of a strong energy transfer from Tb^(3+)to Yb^(3+)*** highest energy transfer efficiency ofη_(ET)≈42%was determined for the CNGG:4 at%Tb,10 at%Yb *** obtained results indicate that CNGG:(Tb^(3+),Yb^(3+))could be efficient new yellowish-green-emitting phosphors.

关键词： Phosphors Tb^(3+)and Tb^(3+)-Yb^(3+)luminescence properties Up-conversion Down-conversion Quantum cutting process Rare earths

Gauge Model Based on Group G×SU（2）

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Chinese Physics Letters 2008年第2期25卷 433-435页

作者： ZET gheorghe MANTA Vasile POPA Camelia Department of Physics Gh. Asachi Technical University Iasi Romania Department of Computers Gh. Asachi Technical University Iasi Romania Faculty of Physics Al. I. Cuza University Iasi Romania

We present a model of gauge theory based on the symmetry group G×SU（2） where G is the gravitational gauge group and SU（2） is the internal group of symmetry. We employ the spacetime of four-dimensional Minkowski, endowed with spherical coordinates, and describe the gauge fields by gauge potentials. The corresponding strength field tensors are calculated and the field equations are written. A solution of these equations is obtained for the case that the gauge potentials have a particular form potentials induces a metric of Schwarzschild type on with spherical symmetry. The solution for the gravitational the gravitational gauge group space.

关键词： pulsars x-ray spectra relativity and gravitation redshift