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Chinese Physics B 2016年第8期25卷 103-112页

作者： parvin R parvin f Ali M S Islam A K M A Department of Physics Rajshahi University Rajshahi-6205 Bangladesh Department of Physics Pabna University of Science and Technology Pabna 6600 Bangladesh International Islamic University Chittagong 154/A College Road Chittagong-4203 Bangladesh

The electronic properties（fermi surface,band structure,and density of states（DOS）） of Al-based alloys AlM3（M=Zr and Cu） and AlCu2Zr are investigated using the first-principles pseudopotential plane wave method within the generalized gradient approximation（GGA）.The structural parameters and elastic constants are evaluated and compared with other available ***,the pressure dependences of mechanical properties of the compounds are *** temperature dependence of adiabatic bulk modulus,Debye temperature,specific heat,thermal expansion coefficient,entropy,and internal energy are all obtained for the first time through quasi-harmonic Debye model with phononic effects for T = 0 K-100 *** parameters of optical properties（dielectric functions,refractive index,extinction coefficient,absorption spectrum,conductivity,energy-loss spectrum,and reflectivity） of the compounds are calculated and discussed for the first *** reflectivities of the materials are quite high in the IR-visible-UV region up to ~ 15 eV,showing that they promise to be good coating materials to avoid solar *** of the properties are also compared with those of the Al-based Ni3 Al compound.

关键词： first principle calculations fermi surface elastic moduli entropy and internal energy optical properties

Elastic, thermodynamic, electronic, and optical properties of recently discovered superconducting transition metal boride NbRuB:An ab-initio investigation

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Chinese Physics B 2017年第10期26卷 339-347页

作者： f parvin S H Naqib Department of Physics University of Rajshahi

The elastic, thermodynamic, electronic, and optical properties of recently discovered and potentially technologically important transition metal boride NbRuB, are investigated using the density functional formalism. Both generalized gradient approximation （GGA） and local density approximation （LDA） are used for optimizing the geometry and for estimating various elastic moduli and constants. The optical properties of NbRuB are studied for the first time with different photon polarizations. The frequency （energy） dependence of various optical constants complement quite well the essential features of the electronic band structure calculations. Debye temperature of NbRuB is estimated from the thermodynamical study. All these theoretical estimates are compared with published results, where available, and discussed in detail. Both electronic band structure and optical conductivity reveal robust metallic characteristics. The NbRuB possesses significant elastic anisotropy. Electronic features, on the other hand, are almost isotropic in nature. The effects of electronic band structure and Debye temperature on the emergence of superconductivity are also analyzed.

关键词： hard materials ternary borides DfT calculations electronic band structure optical properties superconductivity

Synthesis of a PEG-PNIPAm Thermosensitive Dendritic Copolymer and Investigation of Its Self-association

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Chinese Journal of Polymer Science 2015年第1期33卷 192-202页

作者： farzad Seidi parvin Heshmati Department of Chemistry Sanandaj Branch Islamic Azad University University of Kurdistan Department of Chemistry

A Novel thermosensitive dendritic copolymer based on polyethylene glycol（PEG） and poly（Nisopropylacrylamide）（PNIPAm） with a cloud point（CP） around 36 ？C was successfully synthesized by preparation of a dendritic polyol and followed by atom transfer radical polymerization（ATRP） of N-isopropylacrylamide. The dendritic copolymer was characterized using gel-permeation chromatography（GPC）, fTIR and 1H-NMR spectroscopy. The selfassociation behavior of the copolymer in aqueous medium was investigated by dynamic light scattering（DLS） and transmission electron microscopy（TEM）. These investigations confirmed that the dendritic copolymer showed different association behaviors at various temperatures.

关键词： Thermosensitive Dendritic Atom transfer radical polymerization Poly(N-isopropylacrylamide) Polyethylene glycol.

Damaging of cemented carbide end mill with different grain sizes:experimental and simulation

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Rare Metals 2021年第3期40卷 671-678页

作者： Ali Amirnasiri Mahdi Shafiei Haghshenas Nader parvin Department of Mining and Metallurgical Engineering Amirkabir University of Technology(AUT)Tehran ***Iran

The main purpose of the current study was to investigate the effects of the size of WC grains on the damage evolution of WC-Co junk *** finite element method(fEM) simulation results showed that the finegrain(fG) tool retained its cutting edges radii longer than the coarse-grain(CG) *** event leads to the larger wear rate in the CG ***,fEM analysis indicated that through increasing the feeding rate,the wear rate and the cutting forces increased as *** observation of worn tool surface revealed that the formation of micro-pits,micro-cracks,scratching grooves and broken WC grains was among the common signs of the damage for both CG and fG ***,it was found that the defects are more intensive in the CG *** can be due to the lower boundary strength and less WC connectivity in the CG milling *** finer grains also decreased the mean free path in the Co binder and impeded the micro-cracks propagation in the material.

关键词： Cemented carbide Junk mill fEM simulation Wear Grain size

An expeditious synthesis of isoxazoline using cetyltrimethylammonium cerium nitrate:A phase transferring oxidative 1,3-dipolar cycloaddition

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Chinese Chemical Letters 2010年第11期21卷 1287-1290页

作者： parvin Kumar Ashwani Kumar Department of Chemistry Guru Nanak Khalsa P G College Drug Discovery and Research Laboratory Department of Pharmaceutical SciencesGuru Jambheshwar University of Science & Technology

An expeditious and effective method for synthesis of isoxazoline from aldoximes and activated alkenes using cetyltrimethylammonium cerium nitrate at room temperature is *** was completed within short time period in hi... 详细信息

关键词： Cetyltrimethylammonium cerium nitrate Isoxazoline Oxime Activated alkene 1 3-Dipolar addition

Spark Plasma Sintering of Ultrafine YSZ Reinforced Cu Matrix functionally Graded Composite

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Acta Metallurgica Sinica(English Letters) 2016年第12期29卷 1169-1176页

作者： Jafar Mirazimi parvin Abachi Kazem Purazrang Department of Materials Science and Engineering Sharif University of Technology

Copper matrix composites have received more attentions as possible candidate for thermal and electrical conductive materials to be used in electrical contact applications. In this study, five-layered Cu/YSZ （yttria-stabilized zirconia） functionally graded material （fGM） and copper matrix composite specimens containing 3 and 5 vol% YSZ particles plus pure Cu specimen were synthesized using powder metallurgy （PM） route and spark plasma sintering （SPS） consolidation process. The microstructural and some physical, mechanical features of all specimens were characterized. Microscopic examinations showed that ultrafine YSZ particles were distributed in the copper matrix almost homoge- neously. An appropriate interface was observed at each layer of fGM. The density measurement indicated that the graded structure of the composite could be well densified after the SPS process. The microhardness values of various layers of Cu/ YSZ fGM specimen were gradually altered from 56.3 （pure copper side） to 75.2 HV （Cu-5 vol% YSZ side）. The increase of YSZ content resulted in a decrease in electrical conductivity. Additionally, thermal conductivity of Cu/YSZ fGM specimen [308.0 W/（m K）] was determined to be higher than that of the Cu-5 vol% YSZ composite specimen [260.7 W/ （m K）]. Accordingly, it can be concluded that the Cu/YSZ fGM can be a good candidate for the electrical applications, like sliding electrical contacts, where different material characteristics in the same component are required.

关键词： functionally graded material (fGM) Spark plasma sintering (SPS) Composite Microstructure Interface

ATM in breast and brain tumors:a comprehensive review

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Cancer Biology & Medicine 2018年第3期15卷 210-227页

作者： Mehrdad Asghari Estiar parvin Mehdipour Department of Medical Genetics School of Medicine Tehran University of Medical Sciences

The ATM gene is mutated in the syndrome,ataxia-telangiectasia(AT),which is characterized by predisposition to *** with AT have an elevated risk of breast and brain tumors Carrying mutations in ATM,patients with AT have an elevated risk of breast and brain *** increased frequency of ATM mutations has also been reported in patients with breast and brain tumors;however,the magnitude of this risk remains *** the exception of a few common mutations,the spectrum of ATM alterations is heterogeneous in diverse populations,and appears to be remarkably dependent on the ethnicity of *** review aims to provide an easily accessible summary of common variants in different populations which could be useful in ATM screening *** addition,we have summarized previous research on ATM,including its molecular *** attempt to demonstrate the significance of ATM in exploration of breast and brain tumors and its potential as a therapeutic target.

关键词： Breast cancer brain tumor DNA damage DNA repair

Prognostic Value of Promoter Hypermethylation of Retinoic Acid Receptor Beta (RARB) and CDKN2 (p16/MTS1) in Prostate Cancer

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Chinese Journal of Cancer Research 2011年第4期23卷 306-311页

作者： Ameri A Alidoosti A Hosseini Y parvin M Emranpour MH Taslimi f Salehi E fadavi P Department of Radiation Oncology Imam Hossein Hospital Shahid Beheshti University of Medical Sciences Tehran Iran Department of Urology Shahid Modarres Hospital Shahid Beheshti University of Medical Sciences Tehran Iran Department of Pathology Shahid Labbafinezhad Hospital Shahid Beheshti University of Medical Sciences Tehran Iran Department of Immunology Faculty of Medicine Tehran University of Medical Sciences Tehran Iran Department of Radiation Oncology Tehran University of Medical Sciences Tehran Iran

Objective: The molecular mechanism of prostate cancer is poorly understood. The aim of the study was to investigate the prevalence and prognostic value of promoter hypermethylation of retinoic acid receptor beta (RARB) and p16 among benign prostatic hyperplasia (BPH) and prostate cancer patients. Methods: In this case-control study, 63 patients were included in three groups; 21 with BPH as the control group, 21 with prostate cancer and good prognostic factors (based on prostate-specific antigen, Gleason score and stage) as good prognosis group, and 21 with prostate cancer and poor prognostic features as poor prognosis group. The prostate biopsy specimen of each individual was examined for hypermethylation of RARB and p16 promoters by methylation specific PCR (MSPCR). Results: Seven (33.3%) patients with good prognosis and 15 (71.4%) patients with poor prognosis were positive for RARB methylation, which were significantly higher than controls (P ficantly higher than that in the good prognosis group (P =0.02 for RARB and Pfor p16). Conclusion: Hypermethylation of RARB and p16 promoters may predict prognosis in prostate cancer.

关键词： Prostate cancer CpG island DNA methylation Retinoic acid receptor beta (RARB) CDKN2 (p16/MTS1) Methylation Specific PCR

Kaempferol attenuates cognitive deficit via regulating oxidative stress and neuroinflammation in an ovariectomized rat model of sporadic dementia

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Neural Regeneration Research 2018年第10期13卷 1827-1832页

作者： Somayeh Kouhestani Adele Jafari parvin Babaei Cellular and Molecular Research Center Faculty of MedicineGuilan University of Medical Sciences Department of Physiology Faculty of MedicineGuilan University of Medical Sciences Neuroscience Research Center Guilan University of Medical Sciences

Alzheimer＇s disease（AD） is associated with oxidative stress, and ultimately results in cognitive deficit. Despite existing literature on the pathophysiology of AD, there is currently no cure for AD. The present study investigated the effects of kaempferol（Kmp） isolated from the extract of Mespilus germanica L.（medlar） leaves on cognitive impairment, hippocampal antioxidants, apoptosis, lipid peroxidation and neuro-inflammation markers in ovariectomized（OVX） rat models of sporadic AD. Kaempferol, as the main flavonoid of medlar extract has been previously known for anti-oxidative, anti-inflammatory and anti-neurotoxic effects. Thirty-two female Wistar rats were ovariectomized, and randomly divided into four groups： sham, OVX ＋ saline, OVX ＋ streptozotocin（STZ）＋ saline, OVX ＋ STZ ＋ Kmp. Animals received intracerebroventricular injection of STZ（3 mg/kg, twice with one day interval） to establish models of sporadic AD. Intraperitoneal injection of Kmp（10 mg/kg） for 21 days was performed in the OVX ＋ STZ ＋ Kmp group. Spatial learning and memory of rats were evaluated using a Morris water maze. finally, brain homogenates were used for biochemical analysis by enzyme-linked immunosorbent assay. The results showed a significant improvement in spatial learning and memory as evidenced by shortened escape latency and searching distance in Morris water maze in the OVX ＋ STZ ＋ Kmp group compared with the OVX ＋ STZ group. Kmp also exhibited significant elevations in brain levels of antioxidant enzymes of superoxide dismutase and glutathione, while reduction in tumor necrosis factor-α and malondialdehyde. Our results demonstrate that Kmp is capable of alleviating STZ-induced memory impairment in OVX rats, probably by elevating endogenous hippocampal antioxidants of superoxide dismutase and glutathione, and reducing neuroinflammation. This study suggests that Kmp may be a potential neuroprotective agent against cognitive deficit in AD.

关键词： Alzheimer's disease oxidative stress neuroinflammation Mespilus germanica L. Kaempferol neural regeneration

Effect of overburden pressure on determination of reservoir rock types using RQI/fZI,fZI^* and Winland methods in carbonate rocks

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Petroleum Science 2019年第6期16卷 1403-1416页

作者： Aboozar Soleymanzadeh Saeed parvin Shahin Kord Ahwaz faculty of Petroleum Petroleum University of Technology(PUT)AhwazIran

Rock typing is an important tool in evaluation and performance prediction of *** techniques such as flow zone indicator(fZI),fZI~*and Winland methods are used to categorize reservoir rocks into distinct rock ***,these methods are applied to petrophysical data that are measured at a pressure other than reservoir *** the pressure changes the pore structure of rock,the effect of overburden pressure on rock typing should be *** this study,porosity and permeability of 113 core samples were measured at five different *** investigate the effect of pressure on determination of rock types,fZI,fZI~*and Winland methods were *** indicated that although most of the samples remain in the same rock type when pressure changes,some of them show different *** are related to the mineralogy and changes in pore system of the samples due to pressure ***,the number of rock types increases with increasing ***,the effect of overburden pressure on determination of rock types is more clearly observed in the Winland and fZI~****,results revealed that a more precise reservoir dynamic simulation can be obtained by considering the reservoir rock typing process at reservoir conditions.

关键词： Overburden pressure Carbonate rocks Rock type Reservoir quality index flow zone indicator Winland method