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Chinese Journal of Chemistry 2007年第12期25卷 1859-1865页

作者： MOGHIMI, Ali saber-TEHRANI, Mohammad WAQIF-HUSAIN, Syed MOHAMMADHOSSEINI, Majid Department of Chemistry Islamic Azad University Varamin Campus Varamin Iran Department of Chem stry Faculty of Scence Scence and Research Campus lslamic Azad Universty Tehran Iran Department of Chemistry Islamic Azad University of Shahrood Shahrood Iran

A novel and selective method for the fast determination of trace amounts of chromium species in water samples has been developed. The procedure is based on the selective formation of chromium diethyldithiocarbamate complexes at different pH in the presence of Mn（Ⅱ） as an enhancement agent of chromium signals followed by elution with organic eluents and determination by atomic flame absorption spectrometry. The maximum capacity of the employed disks was found to be （396±3） pg and （376±2） pg for Cr（Ⅲ） and Cr（Ⅵ）, respectively. The detection limit of the proposed method is 49 and 43 ng·L^-1 for Cr（Ⅲ） and Cr（Ⅵ）, respectively. The proposed method was successfully applied for determination of chromium species Cr（Ⅲ） and Cr（Ⅵ） in different water samples.

关键词： solid phase extraction sodium diethyldithiocarbamate flame atomic absorption spectrometry octadecyl silica membrane disk

Microstructure and Corrosion Properties of CP-Ti Processed by Laser Powder Bed Fusion under Similar Energy Densities

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Acta Metallurgica Sinica(English Letters) 2022年第9期35卷 1453-1464页

作者： Mohammad Hossein Mosallanejad saber Sanaei Masoud Atapour Behzad Niroumand Luca Iuliano.abdollah Saboori Department of Materials Engineering Isfahan University of Technology84156-83111IsfahanIran Department of Applied Science and Technology Politecnico di TorinoCorso Duca Degli Abruzzi 2410129TorinoItaly Department of Management and Production Engineering Politecnico di TorinoCorso Duca Degli Abruzzi 2410129TorinoItaly

In this work, two types of CP Ti cubes with similar volumetric energy densities(VED) but diff erent process parameters were produced using laser powder bed fusion(LPBF) method. The corrosion behavior of the fabricated specimens was investigated by conducting electrochemical impedance spectroscopy(EIS) and polarization experiments in simulated body fl uid(SBF) solution at 37 °C. The results indicated that the microstructure and porosities, which are of great importance for biomedical applications, can be controlled by changing the process parameters even under constant energy densities. The sample produced with a lower laser power(E1) was featured with a higher level of porosity and thinner alpha laths, as compared with the sample fabricated with a higher laser power(E2). Moreover, results obtained from the bioactivity tests revealed that the sample produced with a higher laser power conferred a slight improvement in the bioactivity due to the higher amount of porosity. Lower laser power and hence higher porosity level promoted the formation of bone-like apatite on the surface of the printed specimens. The potentiodynamic polarization tests revealed inferior corrosion resistance for the fabricated sample with higher porosity. Moreover, the EIS results after diff erent immersion times indicated that a stable oxide film was formed on the surface of samples for all immersion times. After 1 and 3 days of immersion, superior passivation behavior was observed for the sample fabricated with lower laser power. However, very similar impedance and phase values were observed for all the samples after 14 days of immersion.

关键词： Additive manufacturing Laser powder bed fusion Energy density Corrosion Microstructure CP Titanium

Determining the thermophysical properties of Al-doped ZnO nano.articles by the photoacoustic technique

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Chinese Physics B 2013年第7期22卷 280-285页

作者： T. A. El-Brolossy O. saber S. S. Ibrahim Department of Physicsh Faculty of ScienceKing Faisal University Department of Physics Faculty of ScienceAin Shams University Egyptian Petroleum Research Institute Department of Physics Faculty of ScienceCairo University

The thermal conductivity and specific heat capacity of undoped and Al-doped （1–10 at.%） ZnO nano.articles prepared using the solvent thermal method are determined by measuring both thermal diffusivity and thermal effusivity of a pressed powder compact of the prepared nano.articles by using the laser-induced photoacoustic technique. The impact of Al doping versus the microstructure of the samples on such thermal parameters has been investigated. The results reveal an obvious enhancement in the specific heat capacity when decreasing the particle size, while the effect of Al doping on the specific heat capacity is minor. The measured thermal conductivities are about one order of magnitude smaller than that of the bulk ZnO due to several nested reducing heat transfer mechanisms. The results also show that Al doping significantly influences the thermal resistance. Using a simple thermal impedance model, the added thermal resistance due to Al dopant has been estimated.

关键词： ZnO nano.articles microstructure specific heat thermal conductivity

Robust ACO-Based Landmark Matching and Maxillofacial Ano.alies Classification

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Intelligent Automation & Soft Computing 2023年第2期35卷 2219-2236页

作者： Dalel Ben Ismail Hela Elmannai Souham Meshoul Mohamed saber Naceur LTSIRS LR20ES06 Institut National des Sciences Appliquées et de Technologie INSATUniversitéde CarthageTunisia Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia

Imagery assessment is an efﬁcient method for detecting craniofacial ano.alies.A cephalometric landmark matching approach may help in orthodontic diagnosis,craniofacial growth assessment and treatment *** landmark matching and ano.alies detection helps face the manual labelling lim-itations and optimize preoperative planning of maxillofacial *** aim of this study was to develop an accurate Cephalometric Landmark Matching method as well as an automatic system for anatomical ano.alies classiﬁ***,the Active Appearance Model(AAM)was used for the matching *** pro-cess was achieved by the Ant Colony Optimization(ACO)algorithm enriched with proximity ***,the maxillofacial ano.alies were classiﬁed using the Support Vector Machine(SVM).The experiments were conducted on X-ray cephalograms of 400 patients where the ground truth was produced by two *** frameworks achieved a landmark matching error(LE)of 0.50±1.04 and a successful landmark matching of 89.47%in the 2 mm and 3 mm range and of 100%in the 4 mm *** classiﬁcation of ano.alies achieved an accuracy of 98.75%.Compared to previous work,the proposed approach is simpler and has a comparable range of acceptable matching cost and ano.aly classiﬁ*** have also shown that it outperformed the K-nearest neigh-bors(KNN)classiﬁer.

关键词： Maxillofacial ano.alies cephalometric landmarks similarity chi-square distance quadratic assignment problem ant colony optimization SVM

Sequence Stratigraphy and Rudist Facies Development of the Upper Barremian-Lower Ceno.anian Platform, Northern Sinai, Egypt

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Acta Geologica Sinica(English Edition) 2018年第1期92卷 286-310页

作者： Yasser SALAMA Michael GRAMMER Shaban saber Soheir EL-SHAZLY Gouda ABDEL-GAWAD Beni-Suef University Faculty of SciencesGeology Department Boone Pickens School of Geology Oklahoma State University

The Lower Cretaceous sections in northern Sinai are composed of the Risan Aneiza(upper Barremian-middle Albian) and the Halal(middle Albian-lower Ceno.anian) formations. The facies reflect subtle paleobathymetry from inner to outer ramp facies. The inner ramp facies are peritidal, protected to open marine lagoons, shoals and rudist biostrome facies. The inner ramp facies grade northward into outer ramp deposits. The upper Barremian-lower Ceno.anian succession is subdivided into nine depositional sequences correlated with those recognized in the neighbouring Tethyan areas. These sequences are subdivided into 19 medium-scale sequences based on the facies evolution, the recorded hardgrounds and flooding surfaces, interpreted as the result of eustatic sea level changes and local tectonic activities of the early Syrian Arc rifting stage. Each sequence contains a lower retrogradational parasequence set that constituted the transgressive systems tracts and an upper progradational parasequence set that formed the highstand systems tracts. Nine rudist levels are recorded in the upper Barremian through lower Ceno.anian succession at Gabal Raghawi. At Gabal Yelleg two rudist levels are found in the Albian. The rudist levels are associated with the highstand systems tract deposits because of the suitability of the trophic conditions in the rudist-dominated ramp.

关键词： Cretaceous sequence stratigraphy rudists Sinai Egypt

Nonsingular Terminal Sliding Mode Control With Ultra-Local Model and Single Input Interval Type-2 Fuzzy Logic Control for Pitch Control of Wind Turbines

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IEEE/CAA Journal of Automatica Sinica 2021年第3期8卷 690-700页

作者： saber Abrazeh Ahmad Parvaresh Saeid-Reza Mohseni Meisam Jahanshahi Zeitouni Meysam Gheisarnejad Mohammad Hassan Khooban Department of Electrical and Electronics Engineering Shiraz UniversityShiraz ***Iran Department of Electrical Engineering Shahid Bahonar University of KermanKerman 76169-14111Iran Sharif University of Technology Tehran ***Iran Shiraz University of Technology Shiraz ***Iran Department of Electrical Engineering Najafabad BranchIslamic Azad UniversityIsfahan ***Iran Department of Electrical and Computer Engineering Aarhus University8200 AarhusDenmark

As wind energy is becoming one of the fastestgrowing renewable energy resources,controlling large-scale wind turbines remains a challenging task due to its system model nonlinearities and high external *** main goal of the current work is to propose an intelligent control of the wind turbine system without the need for model *** this purpose,a novel model-independent nonsingular terminal slidingmode control(MINTSMC)using the basic principles of the ultralocal model(ULM)and combined with the single input interval type-2 fuzzy logic control(SIT2-FLC)is developed for non-linear wind turbine pitch angle *** the suggested control framework,the MINTSMC scheme is designed to regulate the wind turbine speed rotor,and a sliding-mode(SM)observer is adopted to estimate the unknown phenomena of the *** auxiliary SIT2-FLC is added in the model-independent control structure to improve the rotor speed regulation and compensate for the SM observation estimation *** examinations and comparative analyses were made using a real-time softwarein-the-loop(RT-SiL)based on the dSPACE 1202 board to appraise the efficiency and applicability of the suggested modelindependent scheme in a real-time testbed.

关键词： Interval type-2(IT2)fuzzy logic control modelindependent nonsingular terminal sliding-mode control(MINTSMC) pitch angle control real-time software-in-the-loop(RT-SiL)

Which form of collagen is suitable for nerve cell culture?

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Neural Regeneration Research 2013年第23期8卷 2165-2170页

作者： Mohsen Fathi Najafi saber Zahri Fatemeh Vahedi Leila Esmaililian Toosi Nazila Ariaee Razi Vaccine and Serum Research Institute Departamnt of Biology University of Mohaghegh Ardebili Inflammation and Inflammatory Diseases Research Center Mashhad University of Medical Science

In this study, we investigated the effects of hydrolyzed and non-hydrolyzed collagen and two-di- mensional and three-dimensional collagen matrices on cell survival, attachment and neurite out- growth of primary cultured nerve cells using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide （MTT） colorimetric assay and inverted microscopy. Hydrolyzed collagen facilitated nerve cell survival and neurite outgrowth, but it had no obvious influences on cell attachment. In contrast, non-hydrolyzed two-dimensional collagen matrix had no obvious effects on neurite outgrowth. These findings suggest that hydrolyzed collagen is an ideal nerve cell culture media.

关键词： neural regeneration nerve cells collagen primary culture survival cell attachment growth matrix grants-supported paper neuroregeneration

Spin and pseudospin symmetries of the Dirac equation with shifted Hulthe′n potential using supersymmetric quantum mechanics

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Chinese Physics B 2013年第12期22卷 74-81页

作者： Akpan N. Ikot Elham Maghsoodi Eno J. Ibanga saber Zarrinkamar Hassan Hassanabadi Theoretical Physics Group Department of Physics University of Uyo-Nigeria Department of Basic Sciences Shahrood Branch Islamic Azad University Department of Basic Sciences Garmsar Branch Islamic Azad University

In this paper, we obtain approximate analytical solutions of the Dirac equation for the shifted Hulthén potential within the framework of spin and pseudospin symmetry limits for arbitrary spin–orbit quantum number κ using the supersymmetry quantum mechanics. The energy eigenvalues and the corresponding Dirac wave functions are obtained in closed forms.

关键词： Dirac equation supersymmetry method spin and pseudospin symmetries shifted Hulthén potential

Evaluation of hypolipidemic Marrubium vulgare effect in Triton WR-1339-induced hyperlipidemia in mice

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Asian Pacific Journal of Tropical Medicine 2016年第5期9卷 439-445页

作者： Abeer Y Ibrahim saber F Hendawy Ahmed A A Elsayed Elsayed A Omer Medicinal and Aromatic Plants Researches Dept. Pharmaceutical and Drug Industries Division National Research Centre

Objective: To evaluate the hypocholesterolemic and hypotriglyceridemic activities of four Marrbium vulgare(M. vulgare) herb extracts using Triton WR-1339-induced hyperlipidemia in mice. Methods: Hyperlipidemia was developed by intraperitoneal injection of Triton(200 mg/kg body weight). The animals were divided into main four groups of eight mice each: normal control group, hyperlipidemic control group, hyperlipidemic plus tween-40 control and treated group. The fourth one was divided into four subgroups, petroleum ether extract group, chloroform extract group, ethyl acetate extract group and methanol extract treated group each of them contains two sub-sub group for treating animals with two doses at 0.1 and 0.25 LD50. Results: After 7 h and 24 h of treatment, the intragastric administration of all extracts caused a significant decrease of plasma total cholesterol. Triglyceride levels were also significantly lowered by all extracts while petroleum ether produced the lowest decreasing level. Similar results were observed for LDL-cholesterol concentrations. Furthermore, more polar extracts(methanol and ethyl acetate)-soluble fractions showed a significant ameliorative action on elevated atherogenic index(AI) and LDL/HDL-C ratios, while these atherogenic markers were not statistically suppressed by the chloroform and petroleum ether-soluble extract. Conclusion: The findings indicated that Marrubium may contain polar products able to lower plasma lipid concentrations and might be beneficial in treatment of hyperlipidemia and atherosclerosis.

关键词： Anti-hyperlipidemia Marrubium vulgare Triton Antioxidant Atherogenic index

p53 antibodies,metallothioneins,and oxidative stress markers in chronic ulcerative colitis with dysplasia

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World Journal of Gastroenterology 2011年第19期17卷 2417-2423页

作者： Hala E Hamouda Soha S Zakaria saber A Ismail Mahmoud A Khedr Wael W Mayah Department of Medical Biochemistry Faculty of MedicineTanta University Department of Tropical Medicine Faculty of MedicineTanta University

AIM:To investigate the role of p53 antibodies (p53Abs),metallothioneins (MTs) and oxidative stress markers in the early detection of dysplasia in chronic ulcerative colitis (UC).METHODS:The study included 30 UC patients,15 without dysplasia (group Ⅱ) and 15 with dysplasia (group Ⅲ),in addition to 15 healthy volunteers (group Ⅰ,control subjects).The enzyme-linked immunosorbent assay technique was used to measure serum p53Abs and MTs,while advanced oxidation protein products (AOPPs),and reduced glutathione (GSH) levels were measured by spectrophotometric method in all ***:In group Ⅱ and group Ⅲ compared to group Ⅰ,there were significant increases in serum levels of AOPPs (145.94 ± 29.86 μmol/L and 192.21 ± 46.71 μmol/L vs 128.95 ± 3.06 μmol/L,P 0.096).In contrast,GSH levels showed a significant decrease in both patients' groups (1.87 ± 0.02 μmol/mL and 1.37 ± 0.09 μmol/mL vs 2.49 ± 0.10 μmol/mL,P < 0.05 and P < 0.05 in groups Ⅱ and Ⅲ,respectively) compared with group Ⅰ,and the levels were significantly lower in group Ⅲ than group Ⅱ (P < 0.05).There was a positive correlation between AOPPs and both MTs (r=0.678,P < 0.001) and p53Abs (r=0.547,P < 0.001),and also between p53Abs and MTs (r=0.739,P < 0.001).There was a negative correlation between AOPPs and GSH (r =-0.385,P < 0.001),and also between GSH and both MTs (r=-0.662,P < 0.001) and p53Abs (r=-0.923,P < 0.001).CONCLUSION:Oxidative stress and oxidative cellular damage play an important role in the pathogenesis of chronic UC and the associated carci

关键词： Ulcerative colitis Advanced oxidation protein products Reduced glutathione Metallothionein