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Chinese Journal of Polymer Science 2005年第6期23卷 651-656页

作者： adriana popa Gheorghe Ilia Aurelia Pascariu Smaranda Iliescu Nicoleta Plesu Institute of Chemistry Romanian Academy Bd.Mihai Viteazul 24 R-300223 TimisoaraRomania

A chloromethylated styrene-divinylbenzene copolymer support system functionalized with 4-benzaldehyde and 2-benzaldehyde was prepared. The degree of functionalization with aldehyde groups is well suited for the subsequent use of the products as Wittig reagents. The polymer bound aldehyde was reacted with Wittig reagents to give olefin groups grafted on styrene-divinylbenzene copolymers. The reactions were carded out in phase transfer catalysis conditions. A simple procedure for the calculation of the degree of functionalization and the statistical modeling of the structural repetitive unit of the copolymer are reported.

关键词： Chloromethylated styrene-divinylbenzene copolymer 4-Benzaldehyde 2-Benzaldehyde Phase-transfer catalysis Wittig reaction

Antibacterial and Antioxidant Activities of ZnO Nanoparticles Synthesized Using Extracts of Allium sativum,Rosmarinus officinalis and Ocimum basilicum

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Acta Metallurgica Sinica(English Letters) 2016年第3期29卷 228-236页

作者： Manuela Stan adriana popa Dana Toloman Teofil-Danut Silipas Dan Cristian Vodnar National Institute for Research and Development of Isotopic and Molecular Technologies 67-103 Donat 400293Cluj-Napoca Romania Department of Food Science and Technology University of Agricultural Sciences and Veterinary Medicine 3-5 ManasturStreet 400372 Cluj-Napoca Romania

ZnO nanoparticles（ZnO NPs） were synthesized by chemical method（coprecipitation） and biological method using aqueous extracts of garlic（Allium sativum）,rosemary（Rosmarinus officinalis） and basil（Ocimum basilicum）.The influence of plant extract on the antibacterial and antioxidant activities of green synthesized nanoparticles was *** X-ray diffraction studies reveal that all ZnO samples have hexagonal wurtzite *** particle size of ZnO NPs estimated by transmission electron microscopy analysis（between 14 and 27 nm） varies depending on the synthesis method of nanoparticles and the type of extracts from the plants *** functional groups involved in the biosynthetic procedure were evidenced by Fourier transform infrared *** presence of Mn^（2＋）ions,Zn vacancy complexes and oxygen vacancies in ZnO samples was highlighted by electron paramagnetic resonance *** green synthesized ZnO NPs have shown a good bactericidal activity against Staphylococcus aureus,Bacillus subtilis,Listeria monocytogenes,Escherichia coli,Salmonella typhimurium and Pseudomonas aeruginosa bacterial *** NPs synthesized using extracts of the selected plant species have been found to exhibit more enhanced antibacterial and antioxidant activities as compared to chemical ZnO NPs.

关键词： Zinc oxide nanoparticles Antioxidant activity Antibacterial activity Green synthesis Plant extracts

POLYMER-SUPPORTED SINGLE AND MIXED AMMONIUM AND PHOSPHONIUM SALTS AS CATALYSTS FOR PHASE-TRANSFER REACTIONS

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Chinese Journal of Reactive Polymers 2001年第2期10卷 102-112页

作者： popa adriana PARVULESCU Viorica ILIESCU Smaranda ILIA Gheorghe DEHELEAN Gheorghe Rumanian Academy Institute ofChemistry24 M. Viteazul Str. 1900 Timisoara Roumania. Institute of Physical Chemistry “1.G.Murgulescu" Spl. Independentei 202 Bucharest Romania

In this study was to investigate, by phase-transfer catalysis, the activity of single and mixed ammonium and phosphonium salts grafted on a 揼el-type?styrene-7% divinylbenzene copolymer in the oxidation of benzyl alcohol with hydrogen peroxide. A wide variety of catalysts with different quaternary groups and different quaternary chain length substituents were examined. The activity of single 搊nium?salts increases as a consequence of the association of ammonium and phosphonium salts grafted on the same polymeric support. The activity of polymer-supported ammonium and phosphonium salts increases with the number of carbon atoms contained in the alkyl radicals of the onium and of the functionalization degree with phosphonium groups.

关键词： Quaternary ammonium and/or phosphonium salt grafted on polymer-supports Phase- transfer catalysis Oxidation Triphase catalysis.

ANTIBACTERIAL ACTIVITY OF SINGLE AND MIXED AMMONIUM AND PHOSPHONIUM SALTS GRAFTED ON "GEL-TYPE" STYRENE-DIVINYLBENZENE COPOLYMERS

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Chinese Journal of Reactive Polymers 2000年第2期9卷 118-128页

作者： adriana popa Corneliu-Mircea DAVIDESCU Smaranda ILIESCU Gheorghe ILIA Gheorghe DEHELEAN Lavinia MACARIE Radu TRIF Rumanian Academy Institute of Chemistry24 M.Viteazul Str.1900 TimisoaraRoumania. "Politehnica"University Faculty of Industrial Chemistry and Enviromental EngineeringPhysical Chemistry DepartmentBul.V.Parvan 61900 TimisoaraRoumania. Banat University of Agricultural Science and Veterinary Medicine Microbiology DepartmentCalea Aradului 1191900 TimisoaraRoumania

A systematic study on the synthesis and antibacterial activity of the quaternary "onium" salts grafted on an insoluble "gel-type" styrene-7% divinylbenzene copolymer by polymer-analogous reactions is showed. Antibacterial activity of quaternary ammonium and/or phosphonium salts grafted on polymer-supports has been studied against Staphylococcus aureus and Escherichia coli. A wide variety of "onium" salts bound to macromolecular supports with different quaternary groups and different quaternary chain length substituents were examined. The antibacterial activity of mixed "onium" salts increases as a consequence of the association of ammonium and phosphonium salts grafted on the same polymeric support.

关键词： Antibacterial activity Staphylococcus aureus Escherichia coli Quaternary ammonium and/or phosphonium salts grafted on polymer-supports`

End-Triassic storm deposits in the lacustrine Sichuan Basin and their driving mechanisms

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Science China Earth Sciences 2024年第7期67卷 2383-2400页

作者： Jianli ZENG Tingshan ZHANG Mihai Emilian popa Yongdong WANG Xi ZHANG Liqin LI Yuanyuan XU Ning LU Xiaoqing ZHANG School of Geoscience and Technology Southwest Petroleum University Chengdu 610500China Sichuan Key Laboratory of Natural Gas Geology Southwest Petroleum University Chengdu 610500China Faculty of Geology and Geophysics Doctoral Schoolof Geology Laboratory of Palaeontology University of Bucharest.Bucharest 010041Romania Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008China University of Chinese Academy of Sciences NanjingNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

Storm deposits or tempestites are event sequences formed by storms,requiring at least a water temperature of 26.5℃.While inland lakes are unlikely to form storm deposits because of their limited width and water *** Upper Triassic Xujiahe Formation in the Sichuan Basin is a set of coal-bearing,clastic sequences with dominant sedimentary facies varying from braided river delta to lacustrine settings,with storm deposits widely *** the Zilanba of Guanyuan area,in situ tree trunks on a palaeosol surface in Member Vof the Xujiahe Formation provide new evidence of a storm *** fallen-down directions of nine in situ tree trunks were predominant in the NW direction,contrary to the palaeocurrent direction of the underlying strata,suggesting that the southeasterlies prevailed during the end-Triassic in the northern Sichuan *** mud clasts were frequently recorded in sandstones of the Xujiahe Formation,as well as in the Xindianzi *** mud clasts showed a rip-up or a plastic deformation with upside-down V-shapes,were capped on an erosional surface,showed no transport traces and were therefore interpreted as a storm lag *** megamonsoonal climate prevailed during the Late Triassic,although the megamonsoons themselves could not generate a storm deposition in the Xujiahe Formation due to its low maximum surface wind *** driving mechanism for generating storm deposits in the Xujiahe Formation is suggested to be tropical cyclones over the Tethys Ocean moving eastward,further landfalling on the western margin of the Sichuan *** of storm events in the circum-Tethys region show a widespread storm surge in low latitudes during the *** storm deposits at the top of the Xujiahe Formation represent a sedimentary response to the end-Triassic hyperthermal event.

关键词： Sichuan Basin End-Triassic Xujiahe Formation Storm deposits

Issues and controversies in esophageal inlet patch

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World Journal of Gastroenterology 2019年第30期25卷 4061-4073页

作者： adriana Ciocalteu Petrica popa Mircea Ionescu Dan Ionut Gheonea Department of Gastroenterology Research Center of Gastroenterology and HepatologyUniversity of Medicine and Pharmacy of CraiovaCraiova 200349Romania Department of Anesthesiology and Intensive Care Emergency County Hospital of CraiovaCraiova 200642Romania

The proximal esophagus is rarely examined,and its inspection is often *** chromoendoscopy techniques such as narrow band imaging improve the detection rate of inlet patches in the proximal esophagus,a region in which their prevalence is likely *** studies have reported correlations between these esophageal marks with different issues such as Barrett’s esophagus,but these findings remain *** reports complicate the process of interpreting the clinical features of esophageal inlet patches and underestimate their ***,the limited clinical data and statistical analyses make reaching any conclusions *** is hypothesized that inlet patches are correlated with various esophageal and extraesophageal symptoms,diagnoses and the personalized therapeutic management of patients with inlet patches as well as the differential diagnosis for premalignant lesions or early *** to its potential underdiagnosis,there are no consensus guidelines for the management and follow up of inlet *** review focuses on questions that were raised from published literature on esophageal inlet patches in adults.

关键词： Inlet patch Ectopic gastric mucosa Heterotopic gastric mucosa Esophageal cancer Narrow band imaging Optical chromoendoscopy Cervical esophagus Functional dyspepsia Barrett’s esophagus Helicobacter pylori

Neuroinflammation and comorbidities are frequently ignored factors in CNS pathology

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Neural Regeneration Research 2015年第9期10卷 1349-1355页

作者： Raluca Elena Sandu Ana Maria Buga adriana Uzoni Eugen Bogdan Petcu Aurel popa-Wagner Center of Clinical and Experimental Research University of Medicine and Pharmacy Craiova Department of Psychiatry University of Medicine Rostock Biochemistry Department University of Medicine and Pharmacy "Victor Babes" Timisoara Griffith University School of Medicine Regenerative Medicine Centre

Virtually all drug interventions that have been successful pre-clinically in experimental stroke have failed to prove their efficacy in a dinical setting. This could be partly explained by the complexity and heterogeneity of human diseases as well as the associated co-morbidities which may render neuroprotective drugs less efficacious in dinical practice. One aspect of crucial importance in the physiopathology of stroke which is not completely understood is neuroinflammation. At the pres- ent time, it is becoming evident that subtle, but continuous neuroinflammation can provide the ground for disorders such as cerebral small vessel disease. Moreover, advanced aging and a number of highly prevalent risk factors such as obesity, hypertension, diabetes and atherosclerosis could act as ＂silent contributors＂ promoting a chronic proinflammatory state. This could aggravate the out- come of various pathological entities and can contribute to a number of subsequent post-stroke complications such as dementia, depression and neurodegeneration creating a pathological vicious cycle. Moreover, recent data suggests that the inflammatory process might be dosely linked with multiple neurodegenerative pathways related to depression. In addition, pro-inflammatory cyto- kines could play a central role in the pathophysiology of both depression and dementia.

关键词： aging stroke neuroinflammation comorbidities depression dementia

Review of the bennettitalean genus Weltrichia

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Journal of Palaeogeography 2019年第2期8卷 109-129页

作者： Mihai Emilian popa Faculty of Geology and Geophysics Department of Geology and Doctoral School of GeologyLaboratory of PalaeontologyUniversity of Bucharest

The bennettitalean male reproductive structure Weltrichia Braun 1849 *** 1969(Family Williamsoniaceae) is discussed from several points of view,including anatomy and morphology,species diversity and validity,phytogeographical and stratigraphical distribution,and reproduction strategy.A very rare fossil,genus Weltrichia includes 25 valid species distributed in both hemispheres during Triassic and Jurassic *** contribution critically reviews the systematics of the entire genus,together with its stratigraphical and palaeophytogeographical significance.

关键词： Bennettitales Weltrichia Male reproductive structure Triassic Jurassic

Genus Pronephrium Presl 1851 (Thelypteridaceae) in Romania

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Journal of Palaeogeography 2018年第4期7卷 295-307页

作者： Roxana Pirnea Mihai Emilian popa faculty of geology and geophysics doctoral school of geology university of bucharest 1 N. Ealcescu Ave 010041 BucharestRomania faculty of geology and geophysics department of geology laboratory of palaeontology university of bucharest 1 N. Ealcescu Ave 010041 BucharestRomania

Pronephrium stiriacum（Unger） Knobloch et Kvatek 1976（Filicales, Thelypteridaceae Holttum 1971） is reported from the Oligocene Petrosani Basin and from the Miocene Bozovici Basin in Romania. Morphological variations of this species, such as size of the leaves, venation and marginal teeth, in the Oligocene-Miocene time interval in Romania are described, discussed and illustrated. The distribution of the Thelypteridacean species Pronephrium stiriacum is also discussed regarding its European expansion during the Cenozoic. Moreover, the palaeoecology of this species is discussed based on taphonomy and occurrences, as Pronephrium stiriacum was a secondary coal generator.

关键词： Thelypteridaceae Pronephrium stiriacum Oligocene Miocene Romania

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