检索结果-南通市图书馆

Efficient guiding and focusing of intense laser pulse using periodic thin slits

在线全文

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.huang K.Jiang c.n.Wu h.Peng P.c.hen R.Li h.B.Zhuo c.T.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

Tilted global solar irradiance in Bahrain:an experimental study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

clean Energy 2024年第2期8卷 27-34页

作者： n.Vasilikos c.Georgantopoulou h.Alajaimi S.h.Almajed M.Ahmed D.Mathioulakis School of Mechanical Engineering Bahrain PolytechnicIsa TownPO Box 33349Kingdom of Bahrain School of Mechanical Engineering National Technical University of AthensHeroon Polytechniou 7 StZografos 15773AthensGreece

In the present work,tilted global solar irradiance data are presented and analysed,measured for a period of 1 year on the campus of Bahrain Polytechnic,Kingdom of Bahrain,from both a fixed photovoltaic panel and a moving one via a two-axis solar *** fixed panel faces south with an angle of 26°with respect to the horizontal,coinciding with the local geographical *** second panel is moved by two motors,controlled by a global positioning system and suitable software so that the Sun’s rays are perpendicular to the panel surface.A pyranometer is installed on each panel,recording the tilted global solar irradiance,stored by using a data *** analysis of the data obtained shows a 33%solar energy gain on an annual basis for the moving panel(2780 versus 2088 kWh/m^(2) on the fixed panel).More importantly,in June,when the energy demand in Bahrain is elevated due to the increased residential cooling loads,the solar energy received by the moving panel is 54.7%higher compared with that of the fixed *** a percentage basis,the increase in solar energy from the moving panel is profound in the early morning and late evening ***,the reduction in the solar energy received by the fixed panel from May to June does not appear in the moving panel because of the adjustable orientation of the *** the year,the mean daily solar power varies between 0.37 and 0.56 kW/m^(2) for the fixed panel,and 0.45 and 0.70 kW/m^(2) for the moving *** winter,solar energy fluctuations are elevated due to erratic weather conditions that present a peak standard deviation of 28%of the corresponding *** data presented are useful for potential solar investments in Gulf countries.

关键词： tilted solar irradiance renewable energy solar tracking photovoltaic Gulf cooperation council countries

Empirical model for fusion cross sections of ca-induced reactions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

chinese Physics c 2024年第3期48卷 126-132页

作者： Reddi Rani.L n.Sowmya K.n Sridhar h c.Manjunatha M.M.Armstrong Arasu Department of Physics St.Joseph's College(Autonomous)Affiliated to Bharathidasan UniversityTiruchirappalli620002TNIndia Department of Physics Govt.First.Grade CollegeChikkaballapur-562101KarnatakaIndia Department of Physics Govt.First.Grade CollegeMalur-563160KarnatakaIndia Department of Physics Govt.First.Grade CollegeDevanahalli-562110KarnatakaIndia

A new empirical formula for the astrophysical S-factor has been suggested as a function of the coulomb interaction parameter,center of mass energy,and barrier *** 22 fusion reactions with ^(40,48)ca as projectiles were considered for different targets,leading to compound nuclei with atomic and mass numbers varying between 40≤Z≤≤Z≤112 and 88≤A≤27888≤A≤278,*** fusion cross-sections have been estimated using the geometric factor,the Gamow-Sommerfield factor,and the empirical formula for the *** study's findings showed better agreement with those of available experiments when compared to Wong's *** present work leads to a smaller standard deviation value than Wong's formula when used to correlate the experimental data of calcium-induced fusion ***'s formula provides a good approximation of fusion cross-sections when the center of mass energy is below the fusion barrier when compared to above the fusion barrier.

关键词： fusion cross-sections Wong formula Gamow-Sommerfield-factor Geometric-factor S-factor

Groundwater vulnerability assessment using a GIS-based DRASTIc method in the Erbil Dumpsite area (Kani Qirzhala), central Erbil Basin, north Iraq

在线全文

学校读者我要写书评

暂无评论

Journal of Groundwater Science and Engineering 2024年第1期12卷 16-33页

作者： Masoud h hamed Rebwar n Dara Marios c Kirlas Department of Earth Sciences and Petroleum College of ScienceSalahaddin University-ErbilErbilIraq Department of Petroleum Engineering College of EngineeringKnowledge UniversityErbilIraq Department of Agriculture Faculty of AgricultureForestry and Natural EnvironmentAristotle University of Thessaloniki

Groundwater vulnerability assessment is a crucial step in the efficient management of groundwater resources,especially in areas with intensive anthropogenic activities and groundwater *** the present study,the DRASTIc method was applied using Geographic Information System(GIS)to delineate groundwater vulnerability zones in the Erbil Dumpsite area,central Erbil Basin,north *** showed that the area was classified into four vulnerability classes:Very low(16.97%),low(27.67%),moderate(36.55%)and high(18.81%).The southern,south-eastern and northern parts of the study area exhibited the highest vulnerability potential,while the central-northern,northern and north-western regions displayed the lowest vulnerability ***,results of the single-parameter sensitivity analysis indicated that amongst the seven DRASTIc parameters,the unsaturated zone and the aquifer media were the most influencing *** conclustion,the correlation of 25 nitrate concentration values with the final vulnerability map,assessed using the Pearson correlation coefficient,yielded a satisfactory result of R=0.72.

关键词： DRASTIc Erbil Iraq Groundwater vulnerability assessment nitrate Pollution Sensitivity analysis

cr-induced fusion reactions to synthesize superheavy elements

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

nuclear Science and Techniques 2024年第5期35卷 122-130页

作者： S.Madhu h.c.Manjunatha n.Sowmya B.M.Rajesh L.Seenappa R.S.Susheela Department of Physics R V College of EngineeringBangalore 560074India Visvesvaraya Technological University BelagaviKarnataka 590018India Department of Physics Government First Grade CollegeSrinivasapurKarnataka 563135India Department of Physics Government First Grade CollegeDevanahallyKarnataka 562110India Department of Physics Government First Grade CollegeMulbagalKarnataka 563131India Department of Physics Government First Grade collegeNanjangudOoty RoadMysore 571301India

We investigated ^(50,52-54)cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 *** cross sections produced in this investigation using ^(54)cr projectiles were compared with those obtained in prior *** estimated cross sections from this analysis are consistent with the findings of prior *** the current study,the predicted cross section was found to be 42fb at 236 MeV for ^(53)cr+^(243)Am,23.2 fb at 236 MeV for ^(54)cr+^(247)cm,95.6 fb at 240 MeV for ^(53)cr+248Bk,and 1.33 fb at 242 MeV for ^(53)cr+***,these projected cross sections with excitation energy and beam energy will be useful in future cr-induced fusion reaction investigations.

关键词： Fusion cross sections compound nucleus formation probability Survival probability Evaporation residue cross sections

Early Phases of Star Formation: Testing chemical Tools

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第1期24卷 96-118页

作者： n.c.Martinez S.Paron cOnIcET-Universidad de Buenos Aires.Instituto de Astronomía y Física del Espacio Ciudad Universitaria(C1428EGA)Ciudad Autónoma de Buenos AiresArgentina

Star-forming processes strongly influence the ISM ***,many high-quality databases are available at millimeter *** them,it is possible to carry out studies that review and deepen previous *** these studies involve large samples of sources,it is preferred to use direct tools to study the molecular *** the aim of testing these tools such as the use of the hcn/hnc ratio as a thermometer,and the use of h^(13)cO^(+),hc_(3)n,n_(2)h^(+) and c_(2)h as "chemical clocks," we present a molecular line study toward 55 sources representing massive young stellar objects at different evolutionary stages:infrared dark clouds(IRDcs),highmass protostellar objects(hMPOs),hot molecular cores(hMcs) and ultracompact h II *** found that the use of the hcn/hnc ratio as a universal thermometer in the ISM should be taken with care because the hcn optical depth is a big issue that can affect the ***,this tool should be utilized only after a careful analysis of the hcn spectrum,checking that no line,neither the main nor the hyperfine ones,presents absorption *** point out that the analysis of the emission of h^(13)cO^(+),hc_(3)n,n_(2)h^(+) and c_(2)h could be useful to trace and distinguish regions among IRDcs,hMPOs and *** molecular line widths of these four species increase from the IRDc to the hMc stage,which can be a consequence of the gas dynamics related to the starforming processes taking place in the molecular *** results not only contribute with more statistics,acting as a probe of such chemical tools,useful to obtain information in large samples of sources,but also complement previous works through the analysis of other types of sources.

关键词： stars:formation ISM:molecules ISM:clouds

Imprints of a gravitational wave through the weak field deflection of photons

在线全文

学校读者我要写书评

暂无评论

chinese Physics c 2024年第8期48卷 240-245页

作者： Reggie c.Pantig Ali Övgün Physics Department Mapúa University658 Muralla St.IntramurosManila 1002Philippines Physics Department Eastern Mediterranean UniversityFamagusta99628 North Cyprusvia Mersin 10Turkiye

In this study,we investigate the novel phenomenon of gravitational lensing experienced by gravitational waves traveling past a Schwarzschild black hole perturbed by a specific,first-order,polar gravitational *** apply the Gauss-Bonnet theorem,finding a topological contribution to the deflection of light rays passing near the black *** demonstrate that the deflection angle can be determined by analyzing a region entirely outside the path of the light ray,leading to a calculation based solely on the parameters of the perturbing wave(Legendre polynomial order,l;frequency,σ).This approach offers a unique perspective on gravitational lensing and expands our understanding of black hole interactions with gravitational waves.

关键词： supermassive black holes gravitational waves chaos weak deflection angle Gauss-Bonnet theorem

Effect of cold-working on corrosion induced damage in lug joints

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第6期36卷 175-182页

作者： Ramanath M.n chikmath L. Murthy h. Department of Aerospace Engineering Indian Institute of Technology-MadrasChennai 600036India Department of Aeronautical Engineering KLS Gogte Institute of TechnologyBelagavi 590008India

Lug joints are preferred joineries for transferring heavy loads to parent components in aerospace *** experience corrosion due to environmental conditions,improper surface finishes and rubbing displacement between the pin and *** causes damage of different sizes and shapes near the *** degradation due to corrosion-induced damage is modelled as a through-pit at one of the identified critical locations through stress *** effect of this pit on fatigue crack initiation life is ***-hole is pre-stressed by cold-working and the benefits of inducing plastic wake on the intended performance of the lug joint during the damages due to corrosion are brought out and compared with non-cold-worked *** analysis is performed on this lug joint with *** results obtained highlight the benefits of cold-working and the methodology can be extended to damage growth and analyse the effect of surface treatments for better structural integrity of components of aerospace vehicles.

关键词： Lug joint corrosion crack initiation cold-working Structural integrity

Study of ZnO nanoparticle-supported clay minerals for electrochemical sensors,photocatalysis,and antioxidant applications

在线全文

学校读者我要写书评

暂无评论

chemPhysMater 2024年第1期3卷 83-93页

作者： Mylarappa M n.Raghavendra n.R.Bhumika c.h.chaithra B.n.nagalaxmi K.n.Shravana Kumara Department of chemistry Sri Jagadguru Renukacharya College of ScienceArts&CommerceBengaluru 560009India Department of chemistry East West Institute of TechnologyBengaluru 560091India Department of chemistry Maharani Lakshmi Ammanni College for WomenBengaluru 560012India

In view of the current study’s demonstration of the synthesis of clay-doped ZnO composites,we present a low-cost method for producing clay-metal oxide(clay/ZnO).Utilizing the solution combustion technique,a composite of clay/ZnO was produced utilizing citric acid as both a fuel and a complexing *** hexagonal unit cell structure of the created clay/ZnO may be seen using XRD *** ZnO-infused clay was visible in FE-SEM micrographs as homogenous,sphere-shaped *** possible involvement of clay/ZnO photocatalytic activity in the UV-induced photodegradation of malachite green dye was *** 90%degradation rate shows the composite’s outstanding photocatalytic degradation *** resulting substance was electrochemically analyzed using a constructed electrode in 0.1 M KOh *** increased its sensor capabilities,which now include chemical and biomolecule sensors,and it excelled in cyclic voltammetry-based redox potential *** efficiently evaluate chemically synthesized nPs for electrochemical,sensing,and photocatalytic applications,this study intends to create a solution combustion procedure for the synthesis of clay/ZnO nanocomposite using urea as fuel.

关键词： clay clay/ZnO Photocatalytic Electrochemical sensors