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Consequences of fractal grade distribution for bulk sorting of a copper porphyry deposit

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Geoscience Frontiers 2015年第4期6卷 477-480页

作者： Peter Coghill David Miljak Elizabeth Williams csiro Mineral Resources flagship

We show the presence of fractal ordering of copper grade in bore core data at short range in the Cadia Ridgeway porphyry deposit and measure its persistence after mining by monitoring the output of the mine every 20 s for a month using a large scale, zero field magnetic resonance sensor. A simple model is used to investigate this connection and its consequences for sorting of the ore. Fractal distributions, and their associated power laws, have two features highly favourable for segregating ore： a large proportion of low-grade pods and the large scale spatial clustering of grade.

关键词： FractalMagnetic resonanceCopperPorphyry

Molecular simulation studies of hydrocarbon and carbon dioxide adsorption on coal

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Petroleum Science 2015年第4期12卷 692-704页

作者： Junfang Zhang Keyu Liu M.B.Clennell D.N.Dewhurst Zhejun Pan M.Pervukhina Tongcheng Han csiro Energy flagship Research Institute of Petroleum Exploration and Development Petro China csiro Energy flagship Ian Wark Laboratory

Sorption isotherms of hydrocarbon and carbon dioxide （CO2） provide crucial information for designing processes to sequester CO2 and recover natural gas from unmineable coal beds. Methane （CH4）, ethane （C2H6）, and CO2 adsorption isotherms on dry coal and the temperature effect on their maximum sorption capacity have been studied by performing combined Monte Carlo （MC） and molecular dynamics （MD） simulations at temperatures of 308 and 370 K （35 and 97 ~C） and at pressures up to 10 MPa. Simulation results demonstrate that absolute sorption （expressed as a mass basis） divided by bulk gas density has negligible temperature effect on CH4, C2H6, and CO2 sorption on dry coal when pressure is over 6 MPa. CO2 is more closely packed due to stronger interaction with coal and the stronger interaction between CO2 mole- cules compared, respectively, with the interactions between hydrocarbons and coal and between hydrocarbons. The results of this work suggest that the ＂a＂ constant （pro- portional to TcPc） in the Peng-Robinson equation of state is an important factor affecting the sorption behavior of hydrocarbons. CO2 injection pressures of lower than 8 MPa may be desirable for CH4 recovery and CO2 sequestration. This study provides a quantitative under- standing of the effects of temperature on coal sorptioncapacity for CH4, C2H6, and CO2 from a microscopic perspective.

关键词： Molecular simulation - GROMOS force field -Coal bed methane - Sorption isotherm Bituminous coal Hydrocarbons Carbon dioxide

Science and nanotechnology of superhard materials

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National Science Review 2014年第4期1卷 474-475页

作者： James Boland csiro Energy flagship

Materials science has made spectacular progress recently in the ields of nanophysics and *** is amply demonstrated by the research being undertaken in the area of *** range and depth of research into nanodiamonds is i... 详细信息

关键词： high Science and nanotechnology of superhard materials

A comprehensive approach for assessing the economic contribution of forage and livestock improvement options to smallholder farming enterprises

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Journal of Integrative agriculture 2015年第8期14卷 1573-1580页

作者： Neil Mac Leod Scott Waldron WEN Shi-lin agriculture flagship Commonwealth Scientific and Industrial Research Organisation (CSIRO) University of Queensland Red Soils Experimental Station Chinese Academy of Agricultural Sciences

The importance of livestock production activities to improving the livelihoods of smallholder farming households and the efficiency of their underlying farming systems is increasingly recognized.A rapid increase in livestock numbers, especially beef cattle, and special purpose forages is being promoted for smallholder farms which have traditionally undertaken subsistence cropping activities or simple livestock rearing activities using low quality *** limited plantings of specialized forages combined with a poor knowledge of animal nutrition are a challenge to establishing sustainable livestock enterprises, much public policy and research is now being focused on the use of new forages and improved feeding practices.A number of economic studies have suggested that specialized forage growing and livestock feeding activities can make a positive contribution to smallholder *** studies have typically compared the total level of farm or household income with and without livestock *** attention is given to how much the new forage or livestock activities actually contribute to or draw resources from other farm activities to assess their real economic contribution to the enterprise, and the availability of simple tools to assist in making such assessments are *** paper describes a simple modelling approach that was developed for an Australian Centre for International Agricultural Research（ACIAR）-supported project to explore the real as opposed to apparent economic impact of integrating improved forages and livestock within smallholder farming systems in the Red Soils region of south-central *** of the model is demonstrated using a simple case study of a smallholder enterprise that plans to introduce a new beef cattle rearing activity to its existing farm activity *** case study highlights the importance of explicitly valuing transfers of resources between different farm activities to gauge the real contribution o

关键词： smallholder farming systems economics resource transfers opportunity costs economic profit

Jasmonic acid-isoleucine formation in grapevine(Vitis vinifera L.) by two enzymes with distinct transcription profiles

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Journal of Integrative Plant Biology 2015年第7期57卷 618-627页

作者： Christine Bttcher Crista A.Burbidge Valentina di Rienzo Paul K.Boss Christopher Davies csiro agriculture flagship Glen Osmond Department of Soil Plant and Food SciencesSection of Genetics and Plant BreedingUniversity of Bari "Aldo Moro"

The plant hormone jasmonic acid （JA） is essential for stress responses and the formation of reproductive organs, but its role in fruit development and ripening is unclear. Conjugation of JA to isoleucine is a crucial step in the JA signaling pathway since only JA-Ile is recognized by the jasmonate receptor. The conjugation reaction is catalyzed by JA-amido synthetases, belonging to the family of Gretchen Hagen3 （GH3） proteins. Here, in vitro studies of two grapevine （Vitis vinifera L. cv Shiraz） GH3 enzymes, VvGH3-7 and VvGH3-9, demonstrated JA-conjugating activ- ities with an overlapping range of amino acid substrates, including isoleucine. Expression studies of the correspond- ing genes in grape berries combined with JA and JA-lle measurements suggested a primary role for JA signaling in fruit set and cell division and did not support an involvement of JA in the ripening process. In response to methyl JA （MeJA） treatment, and in wounded and unwounded （distal）leaves, VvGH3-9 transcripts accumulated, indicating a participation in the JA response. In contrast, VvGH3-7 was unresponsive to MeJA and local wounding, demonstrating a differential transcriptional regulation of VvGH3-7 and VvGH3- 9. The transient induction of VvGH3-7 in unwounded, distal leaves was suggestive of the involvement of an unknown mobile wound signal.

关键词： Berry development GH3 grapevine jasmonic acid wound response

Cropping Pattern Modifications Change Water Resource Demands in the Beijing Metropolitan Area

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Journal of Integrative agriculture 2012年第11期11卷 1914-1923页

作者： HUANG Jing Bradley G Ridoutt XU Chang-chun ZHANGHai-lin CHEN Fu College of agriculture and Biotechnology China Agricultural University Beijing 100193 P.R. China Commonwealth Scientific and Industrial Research Organisation (csiro) Sustainable Agriculture Flagship Victoria 3169 Australia

Adequate freshwater supply has become an issue of increasing local and international concern. Reducing water use in agriculture, which is the largest water using sector of the economy, is both important and urgent. The aim of this paper was to quantify how recent cropping pattern changes have influenced water resources in the great Beijing metropolitan area, an expanding megacity which also includes rural counties. Crop production affects blue water use through water consumption and water pollution, the latter assessed here using a critical dilution method. From 1990 to 2010, the total blue water used by crop production declined due to a decrease in overall cropped area, initially in response to local government policies favouring urban development. However, the average blue water use per hectare increased from 2 112 m3 ha-~ yr-~ in 1990 to 2 764 m3 ha-1 yr-1 in 2003, largely as the result of a transition from cereal to vegetable crops, and in particular an increase in intensively managed plastic and glass covered vegetable production systems. Current policies aim to conserve agricultural land, in the interests of food security, and to stimulate cereal production systems with higher ecosystem services provision. As such, in 2010 the average blue water use was 2 425 m3 ha-~ yr-l. These results demonstrate that cropping pattern changes in peri-urban regions and rural communities surrounding the Beijing metropolitan area can have a substantial impact on water resources. They also highlight the tradeoffs between food production and urban and industrial water supply and the need for integrated policy development.

关键词： blue water use water consumption water pollution cropping pattern adjustment peri-urban food production

Effect of the postfeeding interval on olfactory responses of thrips to herbivore-induced cotton plants

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Insect Science 2016年第6期23卷 881-892页

作者： Rehan Silva Gimme H. Walter Lewis J. Wilson Michael J. Furlong School of Biological Sciences University of Queensland St. Lucia Queensland 4072 Cotton Research Unit CSIRO Agriculture Flagship Narrabri NSW 2390 Austrafia

We investigated the responses of 3 thrips species, Frankliniella schultzei Tryborn, E occidentalis Pergrande, and Thrips tabaci Lindeman （Thysanoptera： Thripidae） to herbivore-damaged and undamaged cotton seedlings （Gossypium hirsutum L. [Malvales： Malvaceae]） at a range of time intervals following damage by adult Tetranychus urticae （Koch）, adult T. ludeni （Zacher）（Acari： Tetranychidae） or Helicoverpa armigera （Hubner）（Lepidoptera： Noctuidae） larvae in olfactometer assays. The intensity/frequency of the response of thrips to herbivore-induced plants decreased with time and ultimately disappeared in all cases; however, the rate at which the response declined was related to the herbivore species that inflicted the damage. All 3 species of thrips were attracted to plants damaged by T. urticae for longer than they were to plants damaged by T. ludeni. The duration for which damaged plants remained attractive was also affected by the degree of damage inflicted on cotton seedlings. For example, E schultzei was attracted to plants damaged by a higher density of two-spotted spider mites （100/plant） for much longer than to plants damaged by a lower density of these mites （50/plant）. The results reinforce previous studies that demonstrate that arrangement of variables influences the responses of thrips to their herbivore-induced cotton host plants. Results also show that these responses are variable in time following herbivore damage to cotton plants, which further demonstrates how difficult it is to generalize about the functional significance of these interactions.

关键词： attraction cotton duration induced responses olfactometer Thysanoptera

Spatiotemporal Changes in Soil Nutrients:A Case Study in Taihu Region of China

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Journal of Integrative agriculture 2014年第1期13卷 187-194页

作者： LIU Lei-lei ZHU Yan LIU Xiao-jun CAO Wei-xing XU Mao WANG Xu-kui WANG En-li National Engineering and Technology Center for Information agriculture/Jiangsu Key Laboratory for Information agriculture/Nanjing Agricultural University Soil and Fertilizer Station of Jiangsu Agricultural Department CSRIO Sustainable Agricultural flagship CSIRO Land and Water

The accurate assessment of the spatiotemporal changes in soil nutrients influenced by agricultural production provides the basis for development of management strategies to maintain soil fertility and balance soil nutrients. In this paper, we combined spatial measurements from 2 157 soil samples and geostatistical analysis to assess the spatiotemporal changes in soil organic carbon （SOC）, total nitrogen （TN）, available phosphorus （AP） and available potassium content （AK） from the first soil survey （in the 1980s） to the second soil survey （in the 2000s） in the Taihu region of Jiangsu Province in China. The results showed that average soil nutrients in three soil types all exhibited the increased levels in the 2000s （except for AK in the yellow brown soil）. The standard deviation of soil nutrient contents increased （except for TN in the paddy soil）. Agricultural production in the 20 years led to increases in SOC, TN, AP and AK by 74, 82, 89 and 65%, respectively, of the Taihu areas analyzed. From the 1980s to 2000s all the nugget/sill ratios of soil nutrients indices were between 25 and 75% （except for AK in the yellow brown soil in the 2000s）, indicating moderate spatial dependence. The ratio of AP in the yellow brown soil in the 2000s was 88.74%, showing weak spatial dependence. The spatial correlation range values for SOC, TN, AP and AK in the 2000s all decreased. The main areas showing declines in SOC, TN and AP were in the northwest. For AK, the main region with declining levels was in the east and middle of western areas. Apparently, the increase in soil nutrients in the Taihu region can be mainly attributed to the large increase in fertilizer inputs, change in crop systems and enhanced residues management since the 1980s. Future emphasis should be placed on avoiding excess fertilizer inputs and balancing the effects of the fertilizers in soils.

关键词： soil fertility spatiotemporal variability soil organic carbon total nitrogen phosphorus potassium

Effects of single and dual species herbivory on the behavioral responses of three thrips species to cotton seedlings

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Insect Science 2017年第4期24卷 684-698页

作者： Rehan Silva Gimme H. Walter Lewis J. Wilson Michael J. Furlong School of Biological Sciences The University of Queensland St. Lucia Queensland 4072 Australia Cotton Research Unit CSIRO Agriculture Flagship Locked Bag 59 Narrabri NSW 2390 Australia

This study investigated the olfactory responses of 3 thrips species [Frankliniella schultzei Trybom, E occidentalis Pergrande and Thrips tabaci Lindeman （Thysanoptera： Thripidae）] to cotton seedlings [Gossypium hirsutum L. （Malvales： Malvaceae）] simulta- neously damaged by different combinations of herbivores. Cotton seedlings were damaged by foliar feeding Tetranychus urticae Koch （Trombidiforms： Tetranychidae）, Helicoverpa armigera Hibner （Lepidoptera： Noctuidae）, Aphis＇ gossypii Glover （Hemiptera： Aphidi- dae） or root feeding Tenebrio molitor L. （Coleoptera： Tenebrionidae）. Thrips responses to plants simultaneously damaged by 2 species of herbivore were additive and equivalent to the sum of the responses of thrips to plants damaged by single herbivore species feeding alone. For example, E occidentalis was attracted to T. urticae damaged plants but more attracted to undamaged plants than to plants damaged by H. armigera. Plants simultane- ously damaged by low densities of T. urticae and H. armigera repelled E occidentalis but as T. urticae density increased relative to H. armigera density, E occidentalis attraction to coinfested plants increased proportionally. Thrips tabaci did not discriminate between un- damaged plants and plants damaged by H. armigera but were attracted to plants damaged by T. urticae alone or simultaneously damaged by T. urticae and H. armigera. Olfactometer assays showed that simultaneous feeding by 2 herbivores on a plant can affect predator- prey interactions. Attraction of F. occidentalis to plants damaged by its T. urticae prey was reduced when the plant was simultaneously damaged by H. armigera, T. molitor, or A. gossypii and F. schultzei was more attracted to plants simultaneously damaged by T. urticae and H. armigera than to plants damaged by T. urticae alone. We conclude that plant responses to feeding by I species of herbivore are affected by responses to feeding by other herbivores. These plant-mediated interactions between herbivo

关键词： attraction dual-herbivory Frankliniella occidentalis Frankliniella schultzei induced responses predictability simultaneous damage Thrips tabaci