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Defence Technology（防务技术） 2024年第4期34卷 11-18页

作者： Jacky Cailes Robert Dunsmore Kathryn L.Linge ChemCentre PO Box 1250PerthAustralia

The Marplex Convention was established to prevent the manufacture of unmarked plastic explosives and stipulates that a volatile detection agent must be added at the time of ***,to-date,laboratory testing remains the internationally accepted practice for identifying and quantifying the taggants stipulated in the *** this project,portable FTIR and Raman instruments were tested for their ability to detect 2,3-dimethyl-2,3-dinitrobutane(DMDNB),the chemical marker incorporated in plastic explosives that are manufactured within *** both FTIR and Raman instruments detected solid DMDNB(98%purity),field analysis of plastic explosives at an Australian Defence establishment showed that both FTIR and Raman spectra were matched the relevant explosive(RDX or PETN),rather than the DMDNB *** all three plastic explosives tested,the concentration of DMDNB was measured by SPME-GC-MS to be between 1.8 and 2%,greater than the minimum 1%concentration stipulated by the Marplex *** testing with a plastic explosive analogue confirmed that the minor absorption peaks that would characterize low concentrations of DMDNB were masked by absorption bands from other compounds within the ***,while both FTIR and Raman spectroscopy are suitable for detection of plastic explosives,neither rely on the presence of DMDNB for *** is likely that similar results would be found for other taggants stipulated by the Marplex Convention,given they are also present in concentrations less than 1%.

关键词： Explosive ICAO taggants 2,3-Dimethyl-2,3-dinitrobutane(DMDNB) Fourier transform infrared(FTIR) Raman

Laser beam effect on the entanglement of elastic collisions in quantum plasma

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Communications in Theoretical Physics 2024年第8期76卷 147-155页

作者： Ramin Roozehdar Mogaddam Nasser Sepehri Javan Hosein Mohammadzadeh Department of Physics Ferdowsi University of MashhadPO Box 1436MashhadIran Department of Physics University of Mohaghegh ArdabiliPO Box 179ArdabilIran

In the quantized field formalism, using Kramers-Henneberger unitary transformation as the semi-classical counterpart of Block-Nordsieck transformation, the dynamics of entanglement during the low energy scattering processes in bi-partite systems at the presence of a laser beam fields are studied. The stationary-state Schrodinger equation for the quantum scattering process is obtained for such systems. Then, using partial wave analysis, we introduce a new form of entanglement fidelity considering the effect of high-intensity laser beam fields. The effective potential of hot quantum plasma including plasmon and quantum screening effects is used to obtain the entanglement fidelity ratio as a function of the laser amplitude, and plasmon and Debye length parameters for the elastic electron-ion collisions. It is shown that the plasma free electrons oscillations under interaction with laser beam fields improve the correlations between charged particles and consequently lead to the increase in the system entanglement.

关键词： laser entanglement quantum plasma elastic collision plasmon fidelity

Two-Stream Approximation to the Radiative Transfer Equation:A New Improvement and Comparative Accuracy with Existing Methods

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Advances in Atmospheric Sciences 2024年第2期41卷 278-292页

作者： F.Momo TEMGOUA L.Akana NGUIMDO DNJOMO Environmental Energy Technologies Laboratory(EETL) Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of Electrical and Electronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical modeling of the interaction between solar radiation and the Earth's atmosphere is formalized by the radiative transfer equation(RTE), whose resolution calls for two-stream approximations among other methods. This paper proposes a new two-stream approximation of the RTE with the development of the phase function and the intensity into a third-order series of Legendre polynomials. This new approach, which adds one more term in the expression of the intensity and the phase function, allows in the conditions of a plane parallel atmosphere a new mathematical formulation of γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Delta Function and Modified Eddington, and second-order approximation methods with reference to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion function of the proposed New Method using the fundamental definition of two-stream approximation(F-TSA) developed in a previous work. Notably,New Method has generally better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision for wide domains of the zenith angle μ 0, but tends to deviate from the Disort method with the zenith angle, especially for high values of optical thickness. In spite of this divergence in reflectance for high values of optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained for most cases of optical thickness in this study. An analysis of the Legendre polynomial series for simple functions shows that the high precision is due to the fact that the approximated functions ameliorate the accuracy when the order of approximation increases, although it has been proven that there is a limit order depending on the function from which the precision is lost. This observation indicates that increasing the order of app

关键词： Radiative Transfer Equation two-stream method Legendre polynomial optical thickness moments of specific intensity conversion function transmittance reflectance

Development of sustainable thermal insulation based on bio-polyester filled with date pits

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Journal of Bioresources and Bioproducts 2024年第1期9卷 74-89页

作者： Amal Mlhem Thomas Teklebrhan Evenezer Bokuretsion Basim Abu-Jdayil Chemical&Petroleum Engineering Department United Arab Emirates UniversityPO Box 15551United Arab Emirates National Water and Energy Center United Arab Emirates UniversityPO Box 15551United Arab Emirates

Date palm pit(DPP)-filled poly(-hydroxybutyrate)(PHB)composites were prepared,evaluated,and characterized to determine their thermal insulation *** conductivity values ranged between 0.086 and 0.100 W/(m·K).At a maximum filler concentration(50%(w)),the specific heat capacity and thermal diffusivity were 1183 J/(kg·K)and 0.0689 mm^(2)/s,*** DPP increased the thermal stability,and the highest compressive strength obtained was 80 MPa at 30%filler *** PHB-DPP composites exhibited promising water absorption(less than 6%)and tensile strength(6-14 MPa).Date-pit-based PHB composites could be used in sustainable building engineering and cleaner production.

关键词： Green construction material Sustainable thermal insulator Date pit polyhydroxybutyrate

Quantum speedup and non-Markovianity of an atom in structured reservoirs:pseudomodes as a good description of environmental memory

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Communications in Theoretical Physics 2024年第8期76卷 60-66页

作者： Maryam Hadipour Soroush Haseli Saeed Haddadi Faculty of Physics Urmia University of TechnologyUrmiaIran School of Physics Institute for Research in Fundamental Sciences(IPM)PO Box 19395-5531TehranIran Faculty of Physics Semnan UniversityPO Box 35195-363SemnanIran

Following the recent paper(Teittinen et al 2019 New J. Phys. 21 123041), one can see that in general there is no simple relation between non-Markovianity and quantum speed limit. Here, we investigate the connection between quantum speed limit time and non-Markovianity of an atom in structured environments(reservoirs) whose dynamics is governed by an exact pseudomode master equation(Garraway 1997 Phys. Rev. A 55 2290). In particular, we find an inverse relation between them, which means that the non-Markovian feature of the quantum process leads to speedup of evolution. Thus, there is a link between quantum speedup and memory effects for specific cases of dynamical evolution. Our results might shed light on the relationship between the speedup of quantum evolution and the backflow of information from the environment to the system.

关键词： quantum speed limit non-Markovianity pseudomode method structured environments

Prediction of vertical displacement for a buried pipeline subjected to normal fault using a hybrid FEM-ANN approach

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 428-443页

作者： Hedye JALALI Reza YEGANEH KHAKSAR Danial MOHAMMADZADEH S. Nader KARBALLAEEZADEH Amir H.GANDOMI Department of Civil Engineering Architecture and UrbanismSadjad University of TechnologyPO Box ***MashhadIran Department of Civil Engineering Faculty of EngineeringEqbal Lahoori Institute of Higher EducationPO Box ***MashhadIran Faculty of Civil Engineering Architectureand ArtScience and Research Branch of Islamic Azad UniversityPO Box ***TehranIran Faculty of Engineering&Information Technology University of Technology SydneyUltimoNSW 2007Australia University Research and Innovation Center(EKIK) Óbuda UniversityBudapest 1034Hungary

Fault movement during earthquakes is a geotechnical phenomenon threatening buried pipelines and with the potential to cause severe damage to critical ***,effective prediction of pipe displacement is crucial for preventive management *** study aims to develop a fast,hybrid model for predicting vertical displacement of pipe networks when they experience *** this study,the complex behavior of soil and a buried pipeline system subjected to a normal fault is analyzed by using an artificial neural network(ANN)to generate predictions the behavior of the soil when different parameters of it are *** this purpose,a finite element model is developed for a pipeline subjected to normal fault *** data bank used for training the ANN includes all the critical soil parameters(cohesion,internal friction angle,Young’s modulus,and faulting).Furthermore,a mathematical formula is presented,based on biases and weights of the ANN *** results show that the maximum error of the presented formula is 2.03%,which makes the proposed technique efficiently predict the vertical displacement of buried pipelines and hence,helps to optimize the upcoming pipeline projects.

关键词： buried pipelines normal Fault finite element method multilayer perceptron neural network formulation

Investigating the impact of the universal function of the nuclear proximity potential in heavy-ion fusion cross sections

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Communications in Theoretical Physics 2024年第5期76卷 86-93页

作者： R Gharaei E Sarvari Department of Physics Sciences FacultyHakim Sabzevari UniversityPO Box 397SabzevarIran Department of Physics Faculty of ScienceFerdowsi University of MashhadPO Box 91775-1436MashhadIran Science Faculty Department of PhysicsTarbiat Modares UniversityTehranIran

The fusion barriers and cross sections of 15 colliding systems with 320≤Z_(1)Z_(2)≤1512 are investigated in detail to understand the influence of the universal function of proximity potential formalism in the heavy-ion fusion *** realize this goal,we select three versions of the phenomenological proximity potentials,including Prox.77,Zhang 2013,and Guo 2013,to calculate the nucleus-nucleus *** experimental fusion cross sections for the selected reactions are analyzed using the standard coupled-channel calculations,including couplings to the low-lying 2^(+)and 3^(-)states in the target and *** calculated results show that the universal functions of the Guo 2013 and Prox.77 models provide the lowest and highest fusion barriers,*** addition,it is found that the height of the fusion barriers is enhanced by increasing the mass number of the projectile from light to heavy *** highest sensitivity to the mass number of the projectile belongs to the results of Prox.77.A discussion is also presented on the influence of the universal function on the radial behavior of the interaction potential in the allowed region for overlapping *** results reveal that the best fit to the experimental data of the fusion cross sections for the reactions involving light and medium nuclei is obtained using the universal function of the Zhang 2013 *** the heavier systems,the results of the Guo 2013 model at sub-barrier energies provide a good description of the available data.

关键词： fusion reactions proximity-type potentials universal function coupled-channel calculations

Quantum vortices get stretched

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Frontiers of physics 2024年第3期19卷 225-227页

作者： Emanuel A.L.Henn São Carlos Institute of Physics University of São Paulo-PO Box 36913560-970São CarlosBrazil

Since its discovery, superfluidity [1,2] remains one of the most remarkable phenomena in quantum physics. The onset of the quantum regime in liquid helium is visually striking, when the fluid flows without dissipation or detaches from a rotating bucket, remaining still upon soft rotations. The same phenomenon is present in the context of ultracold bosonic quantum gases where, most of the time, superfluidity walks hand-in-hand with the transition to Bose−Einstein condensation [3].

关键词： quantum rotating rotation

Exploring dielectric phenomena in sulflower-like nanostructures via Monte Carlo technique

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Communications in Theoretical Physics 2024年第4期76卷 188-198页

作者： N Saber Z Fadil Hussein Sabbah A Mhirech B Kabouchi L Bahmad Chaitany Jayprakash Raorane Siva Sankar Sana Hassan Fouad Mohamed Hashem Laboratory of Condensed Matter and Interdisciplinary Sciences(LaMCScI) Research Unit Labelled CNRSTURL-CNRST-17.Faculty of SciencesPO Box 1014Mohammed Ⅴ University in RabatMorocco College of Engineering and Technology American University of the Middle EastEgaila 54200Kuwait School of Chemical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea Applied Medical Science Department Community CollegeKing Saud UniversityPO Box 11433Riyadh Saudi Arabia Department of Dental Health College of Applied Medical SciencesKing Saud UniversityPO Box 12372RiyadhSaudi Arabia

This research focuses on the electric behavior of a mixed ferrielectric sulflower-like *** structure includes a core with spin S_(i)^(Z)-1 atoms and a shell with spin σ_(j)^(Z)-5/2 *** Blume–Capel model and the Monte Carlo technique(MCt)with the Metropolis algorithm are *** are established for absolute zero,investigating stable spin configurations correlated with various physical *** MCt method explores phase transition behavior and electric hysteresis cycles under different physical parameters.

关键词： sulfower-like nanostructure dielectric characteristics Monte Carlo technique phase transition phase diagrams electric hysteresis

Coupled Inversion of Pressure and Tiltmeter Data for Mapping Hydraulic Fracture Geometry

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Acta Mechanica Solida Sinica 2024年第3期37卷 396-405页

作者： Zuorong Chen Xiaofang Jiang Zhejun Pan Robert G.Jeffrey National Key Laboratory of Continental Shale Oil Northeast Petroleum UniversityDaqing163318China SCT Operation Pty.Ltd. PO Box 824WollongongNSW2520Australia

Pressure and tilt data are jointly inverted to simultaneously map the orientation and dimensions of a hydraulic *** deformation induced by a fracture under internal pressure is modeled using the distributed dislocation *** planar fracture is represented by four quarter ellipses,joined at the center and sharing *** configuration provides a straightforward model for characterizing asymmetric fracture *** inverse problem of mapping the fracture geometry is formulated using the Bayesian probabilistic method,combining the a priori information on the fracture model with updated information from pressure and tilt *** the nonlinear inverse problem is achieved by pseudo-randomly sampling the posterior probability distribution through the Markov chain Monte Carlo *** resulting posterior probability distribution is then explored to assess uncertainty,resolution,and correlation between model *** experiments are conducted to verify the accuracy and validity of the proposed analysis method in mapping the fracture geometry using synthetic pressure and tilt data.

关键词： Hydraulic fracture mapping Coupled inversion Tilt Treating pressure