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Synthesis and microstructure characterization of tetragonal Zr1–xTixO2 （x = 0–1） solid solutions

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Journal of Materials Science & Technology 2019年第9期35卷 1966-1976页

作者： Linggen Kong Inna Karatchevtseva Hanliang Zhu Meng Jun Qin Zaynab Aly Nuclear Fuel Cycle Research Australian Nuclear Science and Technology Organisation

Oxide powders of Zr1_xTixO2(x=0-1)solid solutions with micron-sized particles were synthesized via a solution combustion *** synthesis process and Zr/Ti molar ratio were optimized to produce powders with the tetragonal crystal structure.X-ray diffraction,Raman spectroscopy and transmission electron spectroscopy results confirm that a full crystallization microstructure with the single tetragonal phase is obtained after calcination at 600℃while maintaining the crystallite size67 mol%exhibit a tetragonal crystal structure and the embedding Ti in ZrO2 improves the structure *** nitrogen sorption results indicate that the powders possess mesoporous morphology with medium specific surface areas(~10-50 m^2/g).Chemical stability tests show that these powders are relatively stable with negligible removal of titanium and zirconium after elution by 0.5 mol/L *** functional theory was used to calculate the most stable structure with low energy for the selected composition.

关键词： Tetragonal Titanium zirconate Solid solution Chemical synthesis

Reduced Order Modeling & Controller Design for Mass Transfer in a Grain Storage System

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International Journal of Automation and computing 2014年第4期11卷 399-403页

作者： Paramita Guha Sunita Mishra Agrionics Division Central Scientific Instruments Organisation

This paper considers the problem of simulating the humidity distributions of a grain storage system. The distributions are described by partial differential equations(PDE). It is quite difficult to obtain the humidity profiles from the PDE model. Hence, a discretization method is applied to obtain an equivalent ordinary differential equation model. However, after applying the discretization technique, the cost of solving the system increases as the size increases to a few thousands. It may be noted that after discretization,the degree of freedom of the system remain the same while the order increases. The large dynamic model is reduced using a proper orthogonal decomposition based technique and an equivalent model but of much reduced size is obtained. A controller based on optimal control theory is designed to obtain an input such that the output humidity reaches a desired profile and also its stability is *** results are presented to show the validity of the reduced model and possible further extensions are identified.

关键词： Grain storage system finite element method modeling reduced order modeling proper orthogonal decomposition optimal control Lyapunov stability criteria

Synthesis of hierarchical mesoporous Ln_(2)Ti_(2)O_(7)(Ln=Y,Tb-Yb)pyrochlores and uranyl sorption properties

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Journal of Materials Science & Technology 2022年第18期113卷 22-32页

作者： Linggen Kong Inna Karatchevtseva Tao Wei Nicholas Scales Australian Nuclear Science and Technology organisation Lucas Heights NSW2234Australia

Mesoporous structured metal oxides exhibit many active ***,the synthesis of crystalline metal oxides with a ternary composition while maintaining satisfactory pore features is ***,high temperatures are required which inhibit control of pore structure properties including surface area,pore volume,and pore ***,the synthesis of ternary metal oxides Ln_(2)Ti_(2)O_(7)pos-sessing pyrochlore crystal structure is achieved using a novel technique which combines‘soft’and hard colloid templating *** formed materials are of submicron size and composed of∼25-30 nm product‘building blocks’with good chemical and phase *** polycrystalline powders have a high specific surface area(up to 70 m^(2)·g^(-1))and pore volume(∼0.35 cm^(3)·g^(-1))which result in a good adsorp-tion capacity(U uptake closing to 60 mg·g^(-1)).Remarkably,the material exhibits a significant portion of mesopores(mainly 10-40 nm)which facilitate fast adsorption of the cations due to high *** synthetic methodology described herein produces highly homogenous powders and can be applied to other compositions and structures.

关键词： Porous ternary metal oxides Dual template synthesis Lanthanide titanate Pyrochlore Uranium adsorption

Organelle Structures: Bridging Strategy and Technological Processes

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厦门大学学报（自然科学版） 2002年第S1期41卷 249-251页

作者： Rob Dekkers Section Production Technology and organisation

The shifting requirements as imposed on operations ma nagement require adjusting and tailoring the organisational structure to meet ma rket demands. However, translating these requirements directly into hierarchical structure will not ensure the integration of processes across organisational un its and guarantee desirable performance. Therefore, management and management li terature wonders: · How should we connect processes to the external environment within a strategi c framework · Which organisational structures do meet performance requirements · Which choices and freedom do we have within organisational structures · How and when do we implement organisational structures That the hierarchical structure does not meet as such the performance requiremen ts nor did it relate to these became already clear during case studies performed in the ’70s. The conclusion was drawn that organisational changes should affect working processes before they proof to be viable. This required the development of new approach through empirical studies and base d on literature. This led to the development of the organelle structure. The org anelle structure should connect to the strategy and the product flow. Thereto, a decision model has been developed for revealing these relations and the practic al implication. During a number of case studies this methodology has been refined and includes t he strategic choice between variants for the organelle structure with their own performance capabilities; we distinguish about 20 variants ranging between the f unctional organisation and the product flow organisation. These ranges of choice s however can be connected to different order entry points, stemming from logist ic concepts. This extends the performance to improved lead-times and improved c ontrol. Strategic choices relate the organelle structure to external performance criteria dictated by product/market-combinations: · lead-time · quality · costs and internal choices for performance crit

关键词： link Bridging Strategy and Technological Processes Organelle Structures

Damage and geological assessment of the 18 September 2011 M_w 6.9 earthquake in Sikkim,India using very high resolution satellite data

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Geoscience Frontiers 2015年第6期6卷 793-805页

作者： Tapas R.Martha K.Babu Govindharaj K.Vinod Kumar National Remote Sensing Centre(NRSC) Indian Space Research Organisation(ISRO)

Post-disaster very high resolution（VHR） satellite data are potential sources to provide detailed information on damage and geological changes for a large area in a short *** this paper,we studied landslides triggered by the M_w 6.9 earthquake in Sikkim,India which occurred on 18 September 2011 using VHR data from Cartosat-1,GeoEye-1,QuickBird-2 and WorldView-2 *** the earthquake-affected area is located in mostly inaccessible Himalayan terrain,VHR data from these satellites provided a unique opportunity for quick and synoptic assessment of the *** visual change analysis technique through comparison of pre- and post-earthquake images,we assessed the damage caused by the event.A total of 123 images acquired from eight satellites,covering an area of4105 km2 were analysed and 1196 new landslides triggered by the earthquake were *** blockages and severely affected villages were also *** assessment of the terrain highlighted linear disposition of landslides along existing fault scarps,suggesting a reactivation of *** landslide inventory map prepared from VHR images also showed a good correlation with the earthquake shake *** showed that several parts of north Sikkim,particularly Mangan and Chungthang,which are close to the epicentre,were severely affected by the earthquake,and that the event-based landslide inventory map can be used in future earthquake-triggered landslide susceptibility assessment studies.

关键词： International Charter Damage Landslide Fault VHR Disaster

Upgrading and dephosphorization of Western Australian iron ore using reduction roasting by adding sodium carbonate

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International Journal of Minerals,Metallurgy and Materials 2013年第6期20卷 505-513页

作者： De-qing Zhu Tie-jun Chun Jian Pan Li-ming Lu Zhen He School of Minerals Processing and Bioengineering Central South University Commonwealth Scientific and Industrial Research organisation (CSIRO)

The technology of direct reduction by adding sodium carbonate （Na2CO3） and magnetic separation was developed to treat Western Australian high phosphorus iron ore. The iron ore and reduced product were investigated by optical microscopy and scanning electron microscopy. It is found that phosphorus exists within limonite in the form of solid solution, which cannot be removed through traditional ways. During reduction roasting, Na2CO3 reacts with gangue minerals （SiO2 and A1203）, forming aluminum silicate-containing phosphorus and damaging the ore structure, which promotes the separation between iron and phosphorus during magnetic separation. Meanwhile, Na2CO3 also improves the growth of iron grains, increasing the iron grade and iron recovery. The iron concentrate, assaying 94.12wt% Fe and 0.07wt% P at the iron recovery of 96.83% and the dephosphorization rate of 74.08%, is obtained under the optimum conditions. The final product （metal iron powder） after briquetting can be used as the burden for steelmaking by an alactrie *** furnace to rer）la,ce scrar） steel.

关键词： iron ore reduction sodium carbonate ore roasting magnetic separation phosphorus removal

Frequency domain analysis of pre-stressed elastomeric vibration isolators

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Defence Technology（防务技术） 2023年第7期25卷 33-47页

作者： S.Somanath R.Marimuthu Shankar Krishnapillai Indian Space Research organisation Anthariksh BhavanNew BEL RoadBengaluru560231India STR/VSSC Indian Space Research OrganisationThiruvananthapuram695022India Department of Mechanical Engineering IIT MadrasChennai600036India

Two types of elastomeric vibration isolators used for equipment vibration isolation in aerospace vehicles are considered for the present study. These isolators are constructed using elastomers mounted in steel encasings. These isolators are initially deformed statically and dynamic loads are applied on the deformed configuration. To capture the static deformation, equivalent static load corresponding to its load rating and specified displacements are created. Static deformation is computed using Finite Element methods with four node axi-symmetric element which include the geometric non-linear effect for steel and with standard Yeoh hyper-elastic material model for elastomers(Muhammed and Zu, 2012) [1]. Yeoh material constants are derived from uni-axial tension test data of the elastomer specimen. These isolators are subjected to harmonic and random excitations in the pre-deformed state. For numerical analysis, elastomeric constants at dynamic conditions are obtained as complex function of frequency using Dynamic Mechanical Analyzer(DMA) for a range of frequencies. The standard material model of Yeoh is modified incorporating frequency dependant material characteristics and damping in the range of frequencies of interest. A multiplicative non-separable variables law is derived for Yeoh material model to include the effect of static pre-stress, based on the methodology given in literature(Nashif et al.,1985;Beda et al., 2014) [2,3]. The modifications of Yeoh model suitable for frequency domain analysis is the novelty in the present study. In the analysis, while dynamic loads are applied, the configuration is updated considering initial static loading. The frequency response of the isolators is computed using material properties evaluated at progressive dynamic strains until a match in natural frequency is observed. Appropriate damping corrections are then incorporated to match the test observed transmissibility. Then updated material properties are used to compute the

关键词： Elastomer Isolator Axi-symmetric Frequency Random Response Strain amplitude Complex modulus Transmissibility

Effect of heavy load carriage on cardiorespiratory responses with varying gradients and modes of carriage

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Military Medical Research 2019年第1期6卷 53-59页

作者： Subhojit Chatterjee Tirthankar Chatterjee Debojyoti Bhattacharyya Suranjana Sen Madhusudan Pal Defence Institute of Physiology and Allied Sciences Defence Research & Development Organisation Ministry of Defence

Background: The present study was undertaken to determine the effect of different uphill and downhill gradients on cardiorespiratory and metabolic responses of soldiers while carrying heavy military loads in two different ***: Eight physically fit male soldiers with a mean age 32.0±2.0 years, a mean height of 169.5±4.9 cm, and a mean weight of 63.8±8.4 kg volunteered for this study. Each volunteer completed treadmill walking trials at a speed of 3.5 km/h while carrying no external load, 31.4 kg load in a distributed mode(existing load carriage ensembles) and compact mode(new back pack) over 5 different downhill and uphill gradients(–5%, –10%, 0%, 5%, 10%) for 6 min at each gradient. During the walking trials, heart rate(HR), oxygen uptake(VO_2), respiratory frequency(RF) and energy expenditure(EE) were determined by the process of breath-by-breath gas analysis using a K4 b2 system. The average of the last 2 min data from each 6 min walking trial for each individual was subjected to statistical ***: All parameters(HR, VO_2, RF, and EE) gradually increased with the change in gradient from downhill to level to uphill. The distributed mode showed higher values compared to compact mode for all gradients, e.g., for VO_2, there was a 10.7, 7.4, 5.1, 28.2 and 18.7% increase in the distributed mode across the 5 different ***: It can be concluded from the present study that the compact mode of load carriage is more beneficial than the distributed mode in terms of cardiorespiratory responses while walking on downhill and uphill surfaces with a 31.4 kg load.

关键词： Heavy load carriage Cardio respiratory responses Gradients Soldiers

CFD simulations for longwall gas drainage design optimisation

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International Journal of Mining Science and Technology 2017年第5期27卷 777-782页

作者： Qin Johnny Qu Qingdong Guo Hua Coal Mining Research Program The Commonwealth Scientific and Industrial Research Organisation(CSIRO)Brisbane 883Australia

Computational fluid dynamics(CFD) simulation is an effective approach to develop and optimise gas drainage design for underground longwall coal mining. As part of the project supported by the Australian Government Coal Mining Abatement Technology Support Package(CMATSP), threedimensional CFD simulations were conducted to test and optimise a conceptual design which proposes using horizontal boreholes to replace vertical boreholes at an underground coal mine in *** performance between a vertical borehole and a horizontal borehole was first carried out to compare their capacity and effectiveness. Then a series of cases with different horizontal borehole designs were simulated to optimise borehole configuration parameters such as location, diameter, and number of boreholes. The study shows that the horizontal borehole is able to create low pressure sinks that protect the workings from goaf gas ingresses by changing goaf gas flow directions, and that it has the advantage to continuously maintain such low pressure sinks near the tailgate as the longwall advances. An example of optimising horizontal borehole locations in the longwall lateral direction is also given in this paper.

关键词： Goaf gas drainage Horizontal borehole CFD simulation Design optimisation Mining abatement technology