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Energy calibration of laterally segmented electromagnetic calorimeters based on neutral pion detection

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Nuclear Science and Techniques 2017年第11期28卷 164-171页

作者： malek Mazouz Faculté des Sciences de Monastir 5000 Monastir Tunisia

This paper describes a method for energy calibration of laterally segmented electromagnetic calorimeters based on the detection of two-photon decays of π~0 *** calibration procedure performs a X^2 function minimization between the measured π~0 energy in the calorimeter and its expected energy deduced from the π~0 momentum direction. The performance of this technique is demonstrated with a Monte Carlo simulation of an experimental case where biased calibration coefficients are employed. The real calibration coefficients are restored with less than 1% relative accuracy when a sufficient number of π~0 is detected. This technique is applied to monitor daily the calibration coefficients of the calorimeter used in the Jefferson Lab Hall A DVCS experiments.

关键词： Electromagnetic calorimeters Energy calibration Detector modeling and simulations Data processing methods

Bound states of Dirac fermions in monolayer gapped graphene in the presence of local perturbations

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Chinese Physics B 2016年第6期25卷 563-568页

作者： Mohsen Yarmohammadi malek Zareyan Young Researchers and Elite Club Kermanshah BranchIslamic Azad University Department of Physics Institute for Advanced Studies in Basic Sciences (IASBS)

In graphene,conductance electrons behave as massless relativistic particles and obey an analogue of the Dirac equation in two dimensions with a chiral *** this reason,the bounding of electrons in graphene in the form of geometries of quantum dots is *** gapless graphene,due to its unique electronic band structure,there is a minimal conductivity at Dirac points,that is,in the limit of zero *** creates a problem for using such a highly motivated new material in electronic *** of the ways to overcome this problem is the creation of a band gap in the graphene band structure,which is made by inversion symmetry breaking（symmetry of sublattices）.We investigate the confined states of the massless Dirac fermions in an impured graphene by the short-range perturbations for ＂local chemical potential＂ and ＂local gap＂.The calculated energy spectrum exhibits quite different features with and without the perturbations.A characteristic equation for bound states（BSs） has been *** is surprisingly found that the relation between the radial functions of sublattices wave functions,i.e.,f_m~＋（r）,g_m~＋（r）,and f_m^-（r）,g_m^-（r）,can be established by SO（2） group.

关键词： monolayer gapped graphene quantum dots bound states inversion symmetry breaking

Bright artificial light at night is associated with increased body mass,poor reproductive success and compromised disease tolerance in Australian budgerigars(Melopsittacus undulatus)

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Integrative Zoology 2019年第6期14卷 589-603页

作者： Itay malek Abraham HAIM Department of Evolutionary and Environmental Biology University of HaifaMount CarmelHaifaIsrael The Israeli Center for Interdisciplinary Research in Chronobiology University of HaifaHaifaIsrael

Artificial light at night(ALAN)can cause circadian disruption and result in adverse behavioral and ecological effects in free-living birds,but studies on captive pet birds as companion animals have been *** studied the effects of exposure to bright ALAN on body mass,melatonin sulfate levels,reproduction and disease severity in Australian budgerigars(Melopsittacus undulatus)kept in *** the experiment,birds were kept under outdoor temperature,humidity and natural photoperiod from September to December.A total of 48 birds were equally split into 4 groups(6 mating pairs each)and concurrently exposed to ALAN of 200 lux with different duration(0,30,60 and 90 min).Monthly observations were recorded for all dependent parame*** exposure increased mass gain and suppressed melatonin levels in a dose-dependent manner,especially during *** addition,ALAN exposure in all duration groups decreased egg production and reduced hatchability from 61%±14%in the ALAN-unexposed control group to 0%in the ALAN-exposed *** severity was also found to increase in line with the duration of ALAN *** captive ***latus,ALAN exposure was demonstrated to affect photoperiodic regulation with subsequent excess mass gain and reproduction impairment,and increased susceptibility to infections plausibly through duration dose-dependent suppression of *** the best of our knowledge,this is the first study to demonstrate a possible association between acute bright ALAN of increasing duration and both natural development of infections as well as reproductive cessation in captive *** findings could be used to improve breeding conditions of captive birds.

关键词： avian model circadian disruption disease susceptibility light pollution stress responses

Synthesis and characterization of new azo containing Schiff base macrocycle

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Chinese Chemical Letters 2011年第4期22卷 439-442页

作者： Saeed malek-Ahmadi Amir Abdolmaleki Department of Chemistry Isfahan University of TechnologyIsfahan-84156/83111Iran

Fully conjugated Schiff base macrocycle has been prepared through a simple and mild condition,a one-pot cyclization procedure of four-component without using a *** condensation reaction of related bis（hydroxybenzaldehyde） with phenylenediamines to prepare a conjugated[2 ＋ 2]Schiff base macrocycle has been investigated and fluorescent[2 ＋ 2]Schiff base macrocycles with N_2O_2 binding pockets has been prepared and characterized by elemental analysis,^1H NMR,IR,fluorescent,UV-visible and MALDI mass spectroscopies.

关键词： Schiff base macrocycle Non-template Azo compounds

Predictive control of a chaotic permanent magnet synchronous generator in a wind turbine system

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Chinese Physics B 2015年第1期24卷 177-183页

作者： Manal Messadi Adel Mellit Karim Kemih malek Ghanes LRE Laboratory Jijel University BP 98 ouled Aissa Jijel Algeria L2EI laboratory Jijel University BP 98 ouled Aissa Jijel Algeria ECS-ENSEA cergy-pontoise France 6 avenue du Ponceau 95014 Cergy-Pontoise Cedex

This paper investigates how to address the chaos problem in a permanent magnet synchronous generator（PMSG） in a wind turbine system. Predictive control approach is proposed to suppress chaotic behavior and make operating stable;the advantage of this method is that it can only be applied to one state of the wind turbine system. The use of the genetic algorithms to estimate the optimal parameter values of the wind turbine leads to maximization of the power ***, some simulation results are included to visualize the effectiveness and robustness of the proposed method.

关键词： permanent magnet synchronous generator chaotic system genetic algorithm predictive control

Multi-objective optimization of wastewater treatment using electrocoagulation

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Chinese Journal of Chemical Engineering 2024年第11期75卷 152-160页

作者： Sarra Hamidoud malek Bendjaballah Imane Kouadri Mohammed Rabeh Makhlouf Materials Engineering and Industrial Analysis Laboratory M.E.I.A.L.8 May 1945 Guelma UniversityP.O 401Guelma 2400Algeria

This work aims to develop a model that will improve the performance and energy efficiency of a novel electrocoagulation(EC)process utilized in wastewater treatment to extrapolate the findings to an industrial *** Design of experiments(DOE)allows us to maximize treatment efficiency while minimizing energy *** evaluation was conducted by employing aluminum electrodes as sacrificial *** main factors identified in preliminary experiments are the pH of the medium,the applied potential,and the treatment time.A three-level(3^(3))factorial design was employed to examine the relationship between efficiency performance and energy *** optimal conditions,treatment efficiency is around 66%for biological oxygen demand within 5 days(BOD_(5)),98%for chemical oxygen demand(COD),associated with a minimum energy consumption of 2.39 kW·h·mg^(-1)of *** parameters most significantly influenced by the mathematical models obtained were the potential or applied current,treatment time,and their *** modeling results were also correlated with the experimental results and there were minimal *** modeling results were also correlated with the experimental results to assess the accuracy and validity of the model's predictions and there were minimal *** results provide promising possibilities for advancing an environmentally friendly wastewater treatment methodology and an economically viable technological solution.

关键词： Wastewater treatment Green process Electrocoagulation Experimental design Modeling Optimization

Effect of Welding Parameters on Dilution and Weld Bead Geometry in Cladding

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Journal of Materials Science & Technology 2007年第6期23卷 817-822页

作者： M.Nouri A.Abdollah-zadeh F.malek Department of Materials Engineering Tarbiat Modares UniversityP.O.Box 14115-143TehranIran

The effect of pulsed gas metal arc welding （GMAW） variables on the dilution and weld bead geometry in cladding X65 pipeline steel with 316L stainless steel was studied. Using a full factorial method, a series of experiments were carried out to know the effect of wire feed rate, welding speed, distance between gas nozzle and plate, and the vertical angle of welding on dilution and weld bead geometry. The findings indicate that the dilution of weld metal and its dimension i.e. width, height and depth increase with the feed rate, but the contact angle of the bead decreases first and then increases. Meantime, welding speed has an opposite effect except for dilution. There is an interaction effect between welding parameters at the contact angle. The results also show forehand welding or decreasing electrode extension decrease the angle of contact. Finally, a mathematical model is contrived to highlight the relationship between welding variables with dilution and weld bead geometry.

关键词： Pulsed gas metal arc welding (GMAW) Cladding Weld Bead Dilution Full factorial design

Vitamin B12: An efficient type catalyst for the one-pot synthesis of 3,4,5-trisubstituted furan-2(5H)-ones and N-aryl-3-aminodihydropyrrol-2-one-4-carboxylates

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Chinese Chemical Letters 2016年第1期27卷 66-70页

作者： Mehrnoosh Kangani malek-Taher Maghsoodlou Nourallah Hazeri Department of Chemistry Faculty of Sciences University of Sistan and Baluchestan

Vitamin B12 was applied as catalyst for the one-pot three-component synthesis of 3,4,5-trisubstituted furan-2（5H）-ones from the condensation between aldehydes, amines and dialkylacetylendicarboxylates at ambient temperature in Et OH. In addition, N-aryl-3-aminodihydropyrrol-2-one-4-carboxylates were synthesised using mentioned catalyst at ambient temperature in Et OH from condensation between formaldehyde, amines, and dialkylacetylenedicarboxylates. This methodology has number of advantages such as： use of green and nonhazardous catalyst, clean work up, short reaction times,high yields and no need to column chromatography.

关键词： Vitamin B12 3,4,5-Trisubstituted furan-2(5H)-ones N-aryl-3-aminodihydropyrrol-2-one-4- carboxylates

Flood prediction and assessment of vulnerability risk in the southern coasts of the Caspian Sea

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International Journal of Digital Earth 2008年第3期1卷 291-303页

作者： S.Shataee J.malek Gorgan University of Agriculture Sciences and Natural Resources GorganIran Caspian Sea National Research Center SariIran

The southern part of the Caspian Sea shoreline in Iran with a length of 813 km has different topographic *** to sea fluctuation,these zones have various dimensions in different *** the last years,the Caspian Sea experienced enormous destructive *** historical information and tidal gauge measurements showed different ranges of sea rise from30 m to22 m from the mean sea *** the other hand,the probable flooding zone is related to slope gradient of *** help the determination of the probable flooding area owing to sea level rises,the coastal zones can be modelled using geographic information system(GIS)environment as vulnerability risk *** rates would be useful for making decisions in coastal management *** study examined different scenarios of sea rise to determine hazard-flooding rates in the coastal cities of the Mazandaran province and classified them based on vulnerability risk *** 1:2000 scale topographic maps of the coastal zones were prepared to extract topographic information and construct the coastal digital elevation *** the presumption of half-metre sea rise scenarios,the digital elevation models classified eight scenarios from26 to22 *** flooding areas in each scenario computed for 11 cities *** vulnerability risk rate in each rise scenario was computed by dividing the flooded area of each scenario to city *** results showed that in the first four scenarios,from26 to24 m,the Behshahr,Joibar,Neka and Babolsar cites would be more vulnerable than other ***,for the second four scenarios from24 to22 m sea level rise scenario,only the coastal area of Chalous city would be *** was also observed that the coastal region of Behshahr would be critical in total *** studies would be necessary to complete this assessment by considering social-economic and land use information to estimate the exact hazardous and vulnerable zones.

关键词： Caspian Sea flood prediction fluctuation rise scenario vulnerability risk assessment