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Column response curves of nonlinear chromatography for equilibrium isotherms with inflection points

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西北大学学报(自然科学版) 1999年第2期29卷 27-32页

作者： Yu Qiming (School of Environmental Engineering,griffith university,nathan campus, Brisbane, queensland 4111,australia) griffith university 澳大利亚

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Ｉｎｎｏｎｌｉｅａｒｃｈｒｏｍａｔｏｇｒａｐｈｙ，ｉｔｉｓｇｅｎｅｒａｌｙｒｅ－ｇａｒｄｅｄｔｈａｔｔｈｅｍａｉｎｆｅａｔｕｒｅｓｏｆｔｈｅｃｏｌｕｍｎｒｅ－ｓｐｏｎｓｅｃｕｒｖｅｓ（ｏｒｂｒｅａｋｔｈｒｏｕｇｈｃｕｒｖｅｓ）ａｒｅｄｅｔｅｒ－ｍｉｎ...

关键词： nonlinear chromatography equilibrium isotherms inflection points column response carve

Araucaria cunninghamii Seedling response to Different Forms and rates of ^(15)N-Labelled Fertiliser

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Pedosphere 2006年第6期16卷 745-755页

作者： T, J. BLUMFIELD XU Zhi-Hong Centre for Forestry and Horticultural research Nathan Campus Griffith University 170 Kessels Road Nathan Queens- land 4111 （Australia） faculty of Environmental sciences Griffith University Nathan Campus Griffith University 170 Kessels Road Nathan Queensland 4111 （Australia）

Nitrogenous fertilisers are under consideration for promoting the growth of nursery-reared hoop pine （Araucaria cunninghamii Alton ex A. Cunn） seedlings in the establishment phase of second rotation （2r） plantations. Using ^15N- labelled fertilisers, we investigated the effect of different forms （ammonium sulphate, ammonium nitrate, potassium nitrate and urea） and rates of application （0, 150 and 300 mg N kg^-1 dried soil） of fertilisers on the growth, ^15N recovery and carbon isotope composition （δ^13C） of hoop pine seedlings in a 12-month glasshouse trial in southeast queensland, australia. The ^15N-labelled fertilisers were applied to nursery-reared hoop pine seedlings, which were then grown in pots, containing ca. 1.2 kg dried soil, under well watered conditions for 12 months. Four seedlings from each treatment were harvested at 4-month intervals, divided into roots, stem and foliage, with a further subdivision for new and old foliage, and then analysed for ^15N, total N, δ^13C and total C. There was no significant response in the seedling growth to the form or rate of application of nitrogen （N） fertiliser within the 12-month period, indicating that the seedlings did not experience N deficiency when grown on second rotation hoop pine soils. While the combined ^15N recovery from soil and plant remained at around 70% throughout the experiment, the proportion of ^15N recovered from the plants increasing steadily over time. Nitrate containing fertilisers at 150 mg N kg^-1 soil gradually increased seedling foliage δ^13C over the 12-month period, indicating an increase in seedling water use efficiency.

关键词： hoop pine ^15N recovery nitrogen water use efficiency

Wide area real time kinematic decimetre positioning with multiple carrier GNSS signals

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science China Earth sciences 2010年第5期53卷 731-740页

作者： FENG YanMing1 & LI BoFeng1,2 1 faculty of science and technology, queensland university of technology, GPO Box 2434, QLD 4001, australia 2 Department of Surveying and Geo-informatics Engineering, Tongji university, Shanghai 200092, China faculty of science and technology Queensland University of Technology Queensland Australia Department of Surveying and Geo-informatics Engineering Tongji University Shanghai China

This paper presents the technical basis for wide area real time decimetre positioning services using multiple carrier signals transmitted by future GNSS such as modernized GPS and Compass systems. The first step is to form two ionosphere-reduced extra-widelanes (EWL) that have the minimal total noise levels in cycles, considering the effects of the ionospheric and tropospheric delays, orbital error, and phase noise terms in various observational environments. The proposed three carrier ambiguity resolution approach can determine the integer ambiguities of the selected EWL signals with geometry-free and geometry- based estimations respectively over the distances of typically hundreds of kilometres. With two ambiguity-fixed EWL signals, the kinematic positioning solutions can be achieved in decimetre level accuracy. A semi-simulation method is employed to generate three frequency Compass data to demonstrate the above expected performance for decimetre positioning services. Both theoretical and experimental results have demonstrated the overall 3D root mean square accuracy of better than 15 cm obtained through with a phase smoothing process over 120 epochs. The dominating error factor in this positioning result is the residual tropospheric biases, which would become less correlated as the baselines grow beyond hundreds of kilometres. With respect to dual-frequency based precise point positioning and wide area differential positioning solutions, a major advantage of using the third frequency signals is the convergence time being shorten from tens of minutes to a few minutes. In addition, due to the instant ambiguity resolution capability, phase breaks or cycle slips no longer affect the continuity of the solutions. This reliable decimetre positioning capability introduces a significant improvement to safety-of-life, liability-critical and professional applications.

关键词： GNSS three carrier ambiguity resolution real time kinematic decimetre positioning

Numerical Modelling of Air Temperature and Velocity in a Forced Ventilation Piggery

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Journal of Thermal science 2000年第3期9卷 211-216页

作者： ruth Mossad (faculty of Engineering and Surveying, university of Southern queensland, Toowoomba, QLD 4350, australia ) faculty of Engineering and Surveying University of Southern Queensland Toowoomba Australia

Pigs are subjected to intensive environment control and management for higher productivity due to their sensitivity to climatic variation, which affects their growth. The aim of the current work is to numerically model the air speed and temperature in a forced ventilation piggery to achieve optimum environmental control. This work can also help to identify problems in the design of piggeries and offer suggestions for improvements. A steady two-dimensional numerical model including the effect of buoyancy, turbulence and heat generated by the pigs was solved using the computational fluid dynamics software Fluent, using the integral volume method. Air speed and temperature inside the piggery and at the pigs level were predicted for three different locations of ventilation opening, inlet velocities in the range (0.3 - 7 m/s), insulation or no insulation in the external walls, and for 5 ℃ and 32℃ ambient temperatures.

关键词： computational fluid dynamics piggery design forced ventilation numerical modelling.

Magnesium Thixotropic Structures Produced by Controlled Nucleation Method

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特种铸造及有色合金 2007年第S1期27卷 316-319页

作者： H Wang1 Z L Ning2(1.faculty of Engineering and Surveying,university of Southern queensland,Toowoomba,australia 2.School of Materials science and Engineering,Harbin Institute of technology)

Controlled Nucleation Method (CNM) is applied to AZ91 magnesium alloy to produce thixotropic structure suitable for semisolid *** temperature and cooling rate are the two important solidification conditions that can be used for microstructure control in CNM *** have a significant effect on the as-cast microstructure and therefore on semisolid *** pouring temperature produces fine non-dendritic as-cast *** partial remelting and isothermal holding,it develops into a thixotropic *** pouring temperature leads to a coarse dendritic as-cast structure,which turns into an irregular solid network in semisolid *** pouring temperature can combine with high cooling rate to achieve a thixotropic structure.

关键词： Semisolid Processing Solidification Semisolid Feedstock Magnesium Alloy

Effect of pouring temperature on thixotropic microstructure formation of AZ91

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rare Metals 2007年第S1期26卷 180-184页

作者： NING Zhiliang1),WU Peilian1),Wang H.2),CAO Fuyang1),and SUN Jianfei1)1) School of Materials science & Engineering,Harbin Institute of technology,Harbin 150001,China 2) faculty of Engineering & Surveying,university of Southern queensland,Toowoomba,queensland 4350,australia Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China Univ So queensland Fac Engn & Surveying Toowoomba Qld 4350 Australia

The effect of pouring temperature on thixotropic microstructure of AZ91 was *** results show that the pouring temperature has a pronounced effect both on microstructural morphology and grain *** decreasing the pouring temperature,the morphology of grains changes from coarse dendritic to fine dendritic *** fine dendritic structure that was obtained at low pouring temperature developed into a globular structure with a grain size of 60 μm,if the AZ91 was partially remelted and held isothermally at the semisolid state(575 ℃).On the other hand,if the alloy was poured at a high superheat,the particles were irregular and interconnected with a grain size of 180 μm even after 20 min of isothermal holding.

关键词： pouring temperature semisolid microstructural evolution

Surface roughness and removal rate in magnetorheological finishing of a subsurface damage free surface

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Progress in Natural science:Materials International 2005年第6期15卷 538-544页

作者： CHENG Haobo1*, WANG Yingwei2, FENG Zhijing1 and CHENG Kai3(1. State Key Laboratory of Tribiology, Tsinghua university, Beijing 100084, China 2. Department of Material sciences, Changchun university of science and technology, Changchun 130021, China 3. faculty of Information and Engineering Systems, City campus, Leeds LS1 3HE, UK) State Key Laboratory of Tribiology Tsinghua University Beijing 100084 China Department of Material sciences Changchun University of Science and Technology Changchun 130021 China faculty of Information and Engineering Systems City Campus Leeds LS1 3HE UK

Based on computer-controlled optical surfacing, a new technique called magnetorheological finishing (MrF), is presented. The new technique combines the features of conventional loose abrasive machining with a wheel shaped polishing tool. The tool incorporates a host of features and has unprecedented fabricating versatility. The pre-polishing and fine polishing processes can be performed only by adjusting different parameters. The material removal function is studied theoretically and the results of simulation present a Gaussian distribution feature. Based on the established theoretical model, material removal rate experiments involving a parabolic mirror are designed and carried out to determine the effect of controllable parameters on size of the gap between the workpiece and the polishing wheel, rotating speed of the polishing wheel, concentration of volume fraction of non-magnetic particles and polishing time. Further experiments are carried out on the surface microstructure of the workpiece, the final surface roughness with an initial value of 10.98 nm reaches 1.22 nm root mean square (rMS) after 20 min of polishing. The subsurface damage experiment and the atomic force microscopy (AFM) measurement on the polished surface can also verify the feasibility of the MrF technique.

关键词： magnetorheological finishing surface roughness computer controlled optical surfacing subsurface damage removal function.

Phylogeny of Culex theileri virus flavivirus in Spain, Myanmar, Portugal and Turkey

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Asian Pacific Journal of Tropical Medicine 2019年第5期12卷 216-223页

作者： Eleonora Cella Domenico Benvenuto Daniele Donati Francesco Garilli Silvia Angeletti Stefano Pascarella Massimo Ciccozzi Unit of Medical Statistics and Molecular Epidemiology,university campus Bio-Medico of rome School of Nursing,faculty of Medicine,Department of Biomedicine and Prevention,Tor Vergata university faculty of Medicine,university campus Bio-Medico of rome Unit of Clinical Laboratory science,university campus Bio-Medico of rome Department of Biochemical sciences'A.rossi Fanelli',university of rome'La Sapienza' Unit of Medical Statistics and Molecular Epidemiology University Campus Bio-Medico of Rome School of Nursing Faculty of Medicine Department of Biomedicine and Prevention Tor Vergata University faculty of Medicine University Campus Bio-Medico of Rome Unit of Clinical Laboratory science University Campus Bio-Medico of Rome Department of Biochemical sciences"A.rossi Fanelli" University of Rome "La Sapienza"

Objective: To study the genetic diversity of Culex theileri flavivirus and the spread of this virus among Spain, Portugal and ***: A database consisting of 55 sequences of the NS5/3'UTr region of Culex theileri flavivirus group downloaded from GenBank were aligned and manual edited with *** est v.3.7 was used to select the simplest evolutionary model that adequately fitted the sequence *** likelihood analysis was performed using *** phylogenetic signal of the dataset was investigated by the likelihood mapping ***: The phylogenetic tree showed three *** sequences clusterd together with Turkish sequences, Spain and Portugal strains grouped together and two Turkish sequences grouped *** pressure analysis showed a moderate percentage of sites(22.5%) under pervasive negative selection and only 1% under pervasive positive *** sites subject to selective pressure in CTFV rdrp NS5 fragments have been located onto the predicted three-dimensional ***: Phylogenetic and evolutionary analysis can be an important tool for understanding the evolutionary impact of the probable contemporary existence between nonpathogenic and pathogenic flaviviruses among these vectors.

关键词： Culex virus Flaviviridae Phylogenetic analysis Evolution

Design and Expression of a Synthetic phyC Gene Encoding the Neutral Phytase in Pichia pastoris

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 803-811页

作者： Li-Kou ZOU~(1,3) Hong-Ning WANG~(2,1*) Xin PAN~4 Tao XIE~1 Qi WU~5 Zi-Wen XIE~1 Wan-rong ZHOU~1 1 Laboratory of Veterinary and Biotechnology,Sichuan Agricultural university,Ya'an 625014,China 2 Sichuan university Bioengineering research Center for Animal Disease Prevention and Control,Chengdu 610065,China 3 faculty of Environment and resource of Dujiangyan campus,Sichuan Agricultural university,Dujiangyan 611830,China 4 College of Earth science,Chengd university of technology,Chengdu 610059,China 5 College of Life science,Sichuan Agricultural university,Ya'an 625014,China Laboratory of Veterinary and Biotechnology Sichuan Agricultural University Ya'an 625014 China

The 1074-bp phyCs gene （optimized phyC gene） encoding neutral phytase was designed andsynthesized according to the methylotrophic yeast Pichia pastoris codon usage bias without altering theprotein *** expression vector,pP9K-phyCs,was linearized and transformed in *** of total extracellular phytase activity was 17.6 U/ml induced in Buffered Methanol-complex Medium（BMMY） and 18.5 U/ml in Wheat Bran Extract Induction （WBEI） medium at the flask scale,respectively,improving over 90 folds compared with the wild-type *** enzyme showed temperature optimumof 70℃ and pH optimum of *** enzyme activity retained 97% of the relative activity afterincubation at 80℃ for 5 *** of the heavy glycosylation the expressed phytase had a molecularsize of approximately 51 *** deglycosylation by endoglycosylase H （EndoH_f）,the enzyme had anapparent molecular size of 42 *** property and thermostability was affected by the glycosylation.

关键词： design expression synthetic phyC gene neutral phytase Pichia pastoris