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61.
Manimala Selvanathan Khoo Tiong Yann Chang Han Chung Anurita Selvarajoo Senthil Kumar Arumugasamy Vasanthi Sethu 《Water, air, and soil pollution》2017,228(8):299
Biochars, derived from rambutan (Nepheliumlappaceum) peel through slow pyrolysis, were characterised and investigated as potential adsorbent for the removal of copper ion, Cu(II) from aqueous solution. Characteristics of five biochars of rambutan peel with different pyrolytic temperatures ranging from 300 to 700 °C (B300, B400, B500, B600, B700) were studied, and adsorption abilities of respective biochars were evaluated. Adsorption experiments were carried out by varying adsorbent dosage (0.2, 0.4, 0.8, 1.0, 2.0, and 4.0 g/L) and initial copper ion, Cu(II) concentrations (50 and 100 mg/L) to determine the optimum pyrolytic temperature of biochar with high adsorption affinity. The adsorption kinetics were best described by the pseudo-second order model for all the tested biochars, while the adsorption equilibrium best fitted by Langmuir isotherm. The overall results showed that biochar derived at 600 °C can be used as an effective adsorbent for removal of Cu(II) from aqueous solutions. Furthermore, feedforward artificial neural network (FFBP) modelling was performed to compare the simulated results with experimental output data of Thermogravimetric analysis (TGA) and atomic absorption spectroscopy (AAS) analysis which were trained using Levenberg-Marquardt (LM) backpropagation algorithm. The FFBP structure for pyrolysis process comprised of TGA temperature as input and biomass final weight as output. The adsorption modelling was simulated using adsorption time, temperature, biochar dosage and initial Cu(II) concentration as input data, while final Cu(II) concentration was used as output data to the network. Finally, modelling structure of 1-9-1 and 4-8-1 gave best performance with regression, R 2 value of 0.9999 and 0.9547 for TGA and AAS analysis, respectively. 相似文献
62.
Wheat genetic resources enhancement by the International Maize and Wheat Improvement Center (CIMMYT) 总被引:1,自引:0,他引:1
Rodomiro Ortiz Hans-Joachim Braun José Crossa Jonathan H. Crouch Guy Davenport John Dixon Susanne Dreisigacker Etienne Duveiller Zhonghu He Julio Huerta Arun K. Joshi Masahiro Kishii Petr Kosina Yann Manes Monica Mezzalama Alexei Morgounov Jiro Murakami Julie Nicol Guillermo Ortiz Ferrara J. Iván Ortiz-Monasterio Thomas S. Payne R. Javier Peña Matthew P. Reynolds Kenneth D. Sayre Ram C. Sharma Ravi P. Singh Jiankang Wang Marilyn Warburton Huixia Wu Masa Iwanaga 《Genetic Resources and Crop Evolution》2008,55(7):1095-1140
The International Maize and Wheat Improvement Center (CIMMYT) acts as a catalyst and leader in a global maize and wheat innovation
network that serves the poor in the developing world. Drawing on strong science and effective partnerships, CIMMYT researchers
create, share, and use knowledge and technology to increase food security, improve the productivity and profitability of farming
systems and sustain natural resources. This people-centered mission does not ignore the fact that CIMMYT’s unique niche is
as a genetic resources enhancement center for the developing world, as shown by this review article focusing on wheat. CIMMYT’s
value proposition resides therefore in its use of crop genetic diversity: conserving it, studying it, adding value to it,
and sharing it in enhanced form with clients worldwide. The main undertakings include: long-term safe conservation of world
heritage of both crop resources for future generations, in line with formal agreements under the 2004 International Treaty
on Plant Genetic Resources for Food and Agriculture, understanding the rich genetic diversity of two of the most important
staples worldwide, exploiting the untapped value of crop genetic resources through discovery of specific, strategically-important
traits required for current and future generations of target beneficiaries, and development of strategic germplasm through
innovative genetic enhancement. Finally, the Center needs to ensure that its main products reach end-users and improve their
livelihoods. In this regard, CIMMYT is the main international, public source of wheat seed-embedded technology to reduce vulnerability
and alleviate poverty, helping farmers move from subsistence to income-generating production systems. Beyond a focus on higher
grain yields and value-added germplasm, CIMMYT plays an “integrative” role in crop and natural resource management research,
promoting the efficient use of water and other inputs, lower production costs, better management of biotic stresses, and enhanced
system diversity and resilience. 相似文献
63.
Guiguen F Mselli-Lakhal L Durand J Du J Favier C Fornazero C Grezel D Balleydier S Hausmann E Chebloune Y 《American journal of veterinary research》2000,61(4):456-461
OBJECTIVE: To determine whether monocyte-derived macrophages from Mouflon-domestic sheep hybrids (Ovis musimon X Ovis spp) were susceptible to productive infection with caprine arthritis-encephalitis virus (CAEV) in vitro and whether experimental inoculation of Mouflon-domestic sheep hybrids with a molecularly cloned CAEV would result in persistent infection. ANIMALS: 5 Mouflon hybrids. PROCEDURE: Macrophage monolayers were inoculated with virus in vitro. Three animals were inoculated with virus intratracheally. RESULTS: Productive replication of CAEV was demonstrated in monocyte-derived macrophages following in vitro and in vivo inoculation. Titer of infectious cytopathic CAEV produced by macrophages from the Mouflon hybrids was similar to titers produced by macrophages from an infected goat or by synovial membrane cells. Isolation of virus from monocyte-derived macrophages and use of a semiquantitative polymerase chain reaction assay to amplify a portion of the viral genome demonstrated persistent virus replication in all 3 inoculated animals. Two weeks after inoculation of sheep, approximately 1 of 5,000 monocytes was harboring the virus. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that Mouflon-domestic sheep hybrids are susceptible to infection with isolates of CAEV that cause infection in domestic small ruminants. 相似文献
64.
Nicolas?DelpierreEmail author Yann?Vitasse Isabelle?Chuine Joannès?Guillemot Stéphane?Bazot This?Rutishauser Cyrille?B.?K.?Rathgeber 《Annals of Forest Science》2016,73(1):5-25
Key message
We demonstrate that, beyond leaf phenology, the phenological cycles of wood and fine roots present clear responses to environmental drivers in temperate and boreal trees. These drivers should be included in terrestrial ecosystem models.Context
In temperate and boreal trees, a dormancy period prevents organ development during adverse climatic conditions. Whereas the phenology of leaves and flowers has received considerable attention, to date, little is known regarding the phenology of other tree organs such as wood, fine roots, fruits, and reserve compounds.Aims
Here, we review both the role of environmental drivers in determining the phenology of tree organs and the models used to predict the phenology of tree organs in temperate and boreal forest trees.Results
Temperature is a key driver of the resumption of tree activity in spring, although its specific effects vary among organs. There is no such clear dominant environmental cue involved in the cessation of tree activity in autumn and in the onset of dormancy, but temperature, photoperiod, and water stress appear as prominent factors. The phenology of a given organ is, to a certain extent, influenced by processes in distant organs.Conclusion
Inferring past trends and predicting future trends of tree phenology in a changing climate requires specific phenological models developed for each organ to consider the phenological cycle as an ensemble in which the environmental cues that trigger each phase are also indirectly involved in the subsequent phases. Incorporating such models into terrestrial ecosystem models (TEMs) would likely improve the accuracy of their predictions. The extent to which the coordination of the phenologies of tree organs will be affected in a changing climate deserves further research.65.
66.
67.
施肥模式对茶叶品质、产量构成及土壤肥力的影响 总被引:5,自引:0,他引:5
采用田间试验,比较分析了撒施、沟施和沟施覆膜3种施肥模式及沟施覆膜下氮肥施用量对茶叶品质成分、产量构成因子和茶园土壤肥力状况的影响。结果表明:沟施覆膜在一定程度上增加了茶叶产量并改善了品质,提高了茶园土壤的基本肥力状况,沟施次之,撒施效果最差。与沟施相比,沟施覆膜下茶叶的水浸出物、咖啡碱、游离氨基酸含量分别提升2.24%、7.26%、14.68%,茶多酚下降1.88%,芽叶密度、芽叶长度分别提升8.50%、8.15%;土壤表层和深层pH分别下降8.16%和5.30%,表层有机质、全氮、速效氮、速效磷、速效钾分别提升10.87%、26.74%、17.95%、34.69%、25.42%,深层有机质、全氮、速效氮、速效磷、速效钾分别提升10.38%、28.22%、25.64%、15.34%、17.97%。比较沟施覆膜下45 kg·hm-2、60 kg·hm-2、75 kg·hm-2、90 kg·hm-2 4种施氮量对茶叶品质、产量构成以及土壤肥力提高的效果,结果表明随着施氮量的增加,茶叶品质及产量构成和茶园土壤肥力增加,但施氮75 kg·hm-2与90 kg·hm-2处理的茶叶品质及产量构成因子间差异不显著,说明沟施覆膜条件下施氮肥75 kg·hm-2即可满足茶园生产需求。 相似文献
68.
Viktor Finns Jan‐Olof Lill Yvette Heimbrand Martina Blass Timo Saarinen Yann Lahaye Erkki Jokikokko Henry Hgerstrand 《Fisheries Management and Ecology》2020,27(5):490-497
Micro X‐ray fluorescence (µ‐XRF) analysis of otoliths was evaluated as a method to estimate the proportion of stocked one‐summer‐old whitefish Coregonus lavaretus L. in catches of adult fish (n = 20) ascending the River Kemijoki to spawn. Laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS) analysis was applied as control. Polished otoliths were scanned with µ‐XRF to obtain strontium maps that were used to infer visually the provenance of the whitefish. Thirteen of the fish showed signs of being stocked as one‐summer‐old fingerlings. LA‐ICP‐MS was applied to determine the elemental composition in a spot outside the core of the otolith. The results were largely consistent with the visual inspection of the µ‐XRF mapped otoliths. In conclusion, µ‐XRF mapping successfully identified whitefish stocked as one‐summer‐old fingerlings. The vast majority of whitefish returning to the River Kemijoki to spawn were stocked fish. 相似文献
69.
为研究汉中市农村居民生活水污染物在全国范围内的赋存特征及其对环境的污染负荷,测算农村居民生活污水的排放系数,通过实地采样与问卷调查的方式收集数据并采用排污系数法核算了汉中市地区居民污染物排放量。结果表明,受地理地貌、人均日用水量、经济状况、年龄组成和日用餐次数等因素的影响,汉中市不同区域居民的生活水污染物的排放系数有所不同;村处理设施对化学需氧量、五日生化需氧量、氨氮、总氮和总磷的去除率效果显著,但对动植物油的去除效率不明显。调研可为陕西省首次进行的农村生活源水污染物排放量的核算提供数据支撑,进一步健全我国生活污染源信息数据库。 相似文献
70.
为研究黑水虻油替代豆油在草鱼生产实践中的效果,本实验以黑水虻油替代草鱼基础饲料中0(SO)、25%(BSO25)、50%(BSO50)、75%(BSO75)和100%(BSO100)的豆油并配制成5种等氮等脂的饲料,饲喂草鱼[初始体质量(13.37±1.07 g)]56 d后检测生长性能、体成分、血清生化指标、抗氧化能力、肠道和肝脏组织结构及肠道菌群组成等变化。结果显示,各组之间草鱼增重率(WGR)、特定生长率(SGR)、饲料系数(FCR)、肥满度(CF)、脏体比(VSI)和肝体比(HSI)变化均不显著。与SO组相比,BSO25和BSO50组血清超氧化物歧化酶(SOD)活性显著增加,SM75和SM100组的丙二醛(MDA)含量均显著降低,BSO50、BSO75和BSO100组的过氧化氢酶(CAT)活性均显著上升。BSO100组肝细胞呈现为不规则形状,血清中谷草转氨酶(AST)、谷丙转氨酶(ALT)及低密度脂蛋白(LDL-C)的水平均显著高于SO组。BSO100组群落多样性指数Sobs、Shannon和丰富度指数Chao、Ace均显著高于SO组。研究表明,在本实验条件下,黑水虻油替代饲料中100%的豆油虽然不会影响草鱼的生长,能提高草鱼抗氧化能力及肠道菌群的丰度和多样性,但在BSO100组中,草鱼肝脏受损,长期饲喂会对机体产生不利影响,因此在草鱼饲料中黑水虻油不应全部替代豆油,建议替代比例不超过75%。 相似文献