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A review on surface coating strategies for anti-hygroscopic of high energy oxidizer ammonium dinitramide

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Defence Technology（防务技术） 2024年第3期33卷 237-269页

作者： Hongyu Yang Fuyao Chen Yiwen Hu Qiangqiang Lu Lei Xiao Yinglei Wang Fengqi Zhao Wei Jiang gazi Hao National Special Superfine Powder Engineering Research Center of China School of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094China Xi’an Modern Chemistry Research Institute Xi’an 710065China

Ammonium dinitramide(ADN),which has the advantages of high energy density,no halogen and low characteristic signal,is not only considered as a new high-energy oxidizer that is expected to replace the traditional oxidizer ammonium perchlorate(AP)in solid propellants,but also a good performance explosive in ***,due to the strong hygroscopicity of ADN,its application in solid propellants and explosives is greatly *** the hygroscopicity of ADN is the key to realize the wide application of *** this paper,we systematically review the research progress of anti-hygroscopic strategies of ADN *** surface coating methods are focusing on solvent volatilization,solvent-non-solvent,melt crystallization and atomic layer deposition *** characteristics of the different methods are compared and analyzed,and the basis for the classification and selection of the coating materials are introduced in *** addition,the feasibility of material for surface coating of ADN is evaluated by several compatibility analysis *** is highly expected that the liquid phase method(solvent volatilization method,solvent-non-solvent method)would be the promising method for future ADN coating because of its effective,safety and facile ***,polymer materials,are the preferred coating materials due to their high viscosity,easy adhesion,good anti-hygroscopic effect,and heat resistance,which make ADN weak hygroscopicity,less sensitive,easier to preserve and good compatibility.

关键词： Ammonium dinitramide(ADN) Energetic materials Anti-hygroscopic Surface coating Compatibility analysis

New insights in nano-copper chromite catalyzing ultrafine AP:Evaluation of dispersity and mixing uniformity

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Defence Technology（防务技术） 2024年第2期32卷 120-133页

作者： Yong Kou Peng Luo Lei Xiao Yanping Xin Guangpu Zhang Yubing Hu Junqing Yang Hongxu Gao Fengqi Zhao Wei Jiang gazi Hao National Special Superfine Powder Engineering Research Center of China School of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing210094China Xi'an North Huian Chemical Industry Co.Ltd Xi'an710302China Xi'an Modern Chemistry Research Institute Xi'an710065China

Improving the application of nanomaterials has always been a research hotspot in the field of energetic materials(EMs)due to their obvious catalytic effect on the EMs,especially the uniformly dispersed ***,few studies have reported the dispersion of *** this study,the dispersity and mixing uniformity of nano-CuCr_(2)O_(4)was evaluated based on the difference of solid UV light absorption between the nano-catalytic materials and *** nano-CuCr_(2)O_(4)/ultrafine AP composites with different dispersity of nano-CuCr_(2)O_(4)were prepared by manual grinding and mechanical grinding with different grinding strength and griding *** then,the absorbance of different samples at 212 nm was obtained by solid UV testing due to the high repeatability of the absorbance at 210-214 nm for three parallel experiments,and the dispersity of different samples was calculated through the established difference ***,the samples were characterized by XRD,IR,SEM,EDS,DSC and TG-MS,which confirmed that different mixing methods did not change the structure of the samples(XRD and IR),and the mixing uniformity improved with the increase of grinding strength and grinding time(SEM and EDS).The scientificity and feasibility of the difference equation were further verified by *** dispersity of nano-CuCr_(2)O_(4)exhibits a positive intrinsic relationship with its catalytic performance,and the uniformly dispersed nano-CuCr_(2)O_(4)significantly reduces the thermal decomposition temperature of ultrafine AP from 367.7 to 338.8℃.The TG-MS patterns show that the dispersed nano-CuCr_(2)O_(4)advanced the thermal decomposition process of ultrafine AP by about 700 s,especially in the high temperature decomposition stage,and the more concentrated energy release characteristic is beneficial to further enhance the energy performance of AP-based *** above conclusions show that the evaluation method of dispersity based on solid UV curves could pro

关键词： Nano-CuCr_(2)O_(4) Ultrafine AP Dispersity UVeVis diffuse reflectance spectroscopy Thermal decomposition

Spatiotemporal variability of channel and bar morphodynamics in the Gorai-Madhumati River,Bangladesh using remote sensing and GIS techniques

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Frontiers of Earth Science 2020年第4期14卷 828-841页

作者： Md.Yousuf gazi Farhad Hossain Sumiya Sadeak Md.Mahin uddin Department of Geology University of DhakaDhaka1000Bangladesh Department of Geography and Environment University of DhakaDhaka1000Bangladesh

Bangladesh is a riparian country that is criss-crossed by the many tributaries and distributaries of the mighty Ganges,Brahmaputra,and Meghna river ***-Madhumati,a distributary of the Ganges River is an example where morphological development of the river is associated with frequent channel shifting within the catchment *** main objective of this research is to quantify the extent of channel migration,erosion-accretion,river width,sinuosity,and charland morpho-dynamics from 1972 to 2018 using geospatial techniques combined with satellite images and hydrological *** study also addressed the impacts of Farakka Barrage construction in India on the shifting,flow behavior,and siltation of Gorai-Madhumati *** study shows that bar surface areas have abnormally increased in both segments after 1975 due to the construction of Farakka *** flow in the Gorai-Madhumati has dropped remarkably in the downstream and instigated huge sedimentation in this *** of the time series satellite images revealed that the morphology of the river channel experienced huge changes simultaneously with the changes in the seasonal flow and sedimentation all over the study *** trend has frequently shifted and taken place in the NW and NE direction in the observed sections of the *** the study period,total amount of accretion was greater than the net percentage of erosion on both banks of the *** discharge,bar accretion,and erosion history show that the Gorai-Madhumati River will no longer exist with the present flowing condition without attention and proper river management.

关键词： channel migration erosion-accretion morphodynamics geospatial techniques Gorai-Madhumati Bangladesh

Zinc and cadmium accumulation in cabbage aphid （Brevicoryne brassicae） host plants and developmental instability

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Insect Science 2009年第1期16卷 65-71页

作者： gazi Gorur Department of Biology Science and Arts Faculty Nigde University 51100 Nigde Turkey

Developmental instability in morphological characters can occur during individual development due to various environmental stresses. Fluctuating asymmetry （FA） is often used as a measurement of developmental instability, but within-environment variation （CVo） is also considered an indicator of developmental instability. Cabbage aphid （Brevicoryne brassicae） populations were reared on zinc- （Zn） or cadmium- （Cd） contaminated cabbage and radish plants. Developmental instability indicators were measured and their relations with fitness were explored. Results revealed that cabbage aphids exposed to Cd and Zn displayed considerable developmental instability, particularly fluctuating asymmetry. Differences in developmental instability between the two metals were also detected, as well as differences between the two developmental instability measurements. For almost all measured traits, FA was greater on Cd- and Zn-contaminated compared to non-contaminated host plants. In contrast, CVo of some traits was greater on non-contaminated host plants, yet for other traits CVo was greater on contaminated host plants. There were also non-significant inverse relationships between FA and fitness of cabbage aphid populations. Due to weak correlations between FA and different patterns of two developmental instability measurements, this study does not support the hypothesis that developmental instability is a useful bioindicator of environmental quality.

关键词： aphid fluctuating asymmetry heavy metal

A Survey on Belief Propagation Decoding of Polar Codes

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China Communications 2021年第8期18卷 133-168页

作者： Ahmet Cagrı Arlı Orhan gazi Digital Design and Verification Engineering Department Electra ICAnkaraTurkiye Electronic and Communication Engineering Cankaya UniversityAnkaraTurkiye

The increasing data traffic rate of wireless communication systems forces the development of new technologies *** high data rate,extremely low latency and improvement on quality of service are the main subjects of next generation 5G wireless communication systems which will be in the people’s life in the years of *** the newest and first mathematically proven forward error correction code,polar code is one of the best candidates among error correction methods that can be employed for 5G wireless *** aim of this tutorial is to show that belief propagation decoding of polar codes can be a promising forward error correction technique in upcoming 5G ***,we survey the novel approaches to the belief propagation based decoding of polar codes and continue with the studies about the simplification of these ***,early detection and termination methods and concept of scheduling are going to be presented throughout the ***,polar construction algorithms,error types in belief propagation based decoders and hardware implementations are going to be ***,this tutorial proves that the BP based decoding of polar codes has a great potential to be a part of communication standards.

关键词： polar codes belief propagation 5G

Target Capturing in an Ellipsoidal Region for a Swarm of Double Integrator Agents

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IEEE/CAA Journal of Automatica Sinica 2022年第5期9卷 801-811页

作者： Antonio Bono Luigi D'Alfonso Giuseppe Fedele Veysel gazi IEEE Department of Informatics ModelingElectronics and Systems EngineeringUniversity of CalabriaRende 87036Italy Dept.Electrical and Electronics Eng. Faculty of EngineeringMarmara UniversityIstanbul 34722 Department of Control and Automation Engineering Faculty of Electrical and Electronics EngineeringYildiz Technical UniversityEsenler 34220Turkey

In this paper we focus on the target capturing problem for a swarm of agents modelled as double integrators in any finite space *** agent knows the relative position of the target and has only an estimation of its velocity and *** that the estimation errors are bounded by some known values,it is possible to design a control law that ensures that agents enter a user-defined ellipsoidal ring around the moving *** know the relative position of the other members whose distance is smaller than a common detection ***,in the case of no uncertainty about target data and homogeneous agents,we show how the swarm can reach a static configuration around the moving *** simulations are reported to show the effectiveness of the proposed strategy.

关键词： Agents-based systems cooperative control swarms target-capturing

Phytoplankton abundance and community structure in the Antarctic polar frontal region during austral summer of 2009

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Chinese Journal of Oceanology and Limnology 2013年第1期31卷 21-30页

作者： SHRAMIK Patil RAHUL Mohan SUHAS Shetye SAHINA gazi National Centre for Antarctic and Ocean Research

The Antarctic polar front region in the Southern Ocean is known to be most productive. We studied the phytoplankton community structure in the Indian sector at this frontal location during late austral summer (February, 2009) onboard R/V Akademic Boris Petrov. We used the phytoplankton and microheterotrophs abundance, as also the associated physico-chemical parameters to explain the low phytoplankton abundance in the study region. This study emphasizes the shift of phytoplankton, from large (>10 μm) to small (10 μm) phytoplankton abundance during the late austral summer. This study highlights the highly productive polar front nevertheless becomes a region of low phytoplankton abundance, due to community shifts towards pico-phytoplankton (<10 μm) during late austral summer.

关键词： Southern Ocean polar front diatom ciliate dinoflagellate

A numerical technique based on collocation method for solving modified Kawahara equation

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Journal of Ocean Engineering and Science 2018年第1期3卷 67-75页

作者： Turgut Ak S.Battal gazi Karakoc Department of Transportation Engineering Yalova UniversityYalova77200 Turkey Department of Mathematics Faculty of Science and ArtNevsehir Haci Bektas Veli UniversityNevsehir50300 Turkey

In this article,a numerical solution of the modified Kawahara equation is presented by septic B-spline collocation *** the von-Neumann stability analysis,the present method is shown to be unconditionally stable.L 2 and L∞error norms and conserved quantities are given at selected *** accuracy of the proposed method is checked by test problems including motion of the single solitary wave,interaction of solitary waves and evolution of solitons.

关键词： Modified Kawahara equation Finite element method Collocation Solitary waves B-spline

Simulation of Pollutant Transport in Marmaris Bay

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China Ocean Engineering 2001年第4期16卷 565-578页

作者： Lale BALASCivil Engineering Department Faculty of Engineering and Architecture, gazi University,Maltepe, 06570 Ankara, Turkey E-mail: bulas@mmf. gazi.edu.tr, Fax: + 90 312 2318434 Civil Engineering Department Faculty of Engineering and Architecture Gazi University Mallepe 06570 Ankara Turkey

The circulation pattern and the pollutant transport in the Marmaris Bay are simulated by the developed three-dimensional baroclinic model. The Marmaris Bay is located at the Mediterranean Sea coast of Turkey. Since the sp ring tidal range is typically 20-30 cm, the dominant forcing for the circulation and water exchange is due to the wind action. In the Marmaris Bay, there is sea outfall discharging directly into the bay. and that threats the bay water quality significantly. The current patterns in the vicinity of the outfall have been observed by tracking drogues which are moved by currents at different water depths. In the simulations of pollutant transport, the coliforms-counts is used as the tracer. The model provides realistic predictions for the circulation and pollutant transport in the Marmaris Bay. The transport model component predictions well agree with the results of a laboratory model study.

关键词： sea out fall modelling circulation transport pollutant