857 resultados para NAG-NAM


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This manual has been produced by members of the national acoustics group (NAG) and represents the first in a series of outputs designed to promote co-ordination and consistency in Agency hydroacoustic surveys. It is designed as a field guide for Agency staff operating the SIMRAD EY500 portable scientific echosounder. It should be simplistic enough for the newcomer to EY500 to be able to set up and run a mobile hydroacoustic survey with some knowledge of the supporting theory. It should act as guidance for standardisation of survey procedures providing a concise list of settings and recommendations that can be used as a quick reference guide in the field. This manual condenses 5 years of practical experience of surveying fish populations using Simrad hardware and software for surveying large rivers and still waters throughout England and Wales. This document should be used as a companion to the manufacturers instruction manual and not act as a substitute for it.

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During the rainy season in extensive river floodplains and deltaic lowlands, floods render the land unavailable for crop production for several months each year. These waters are considerably underutilized in terms of managed aquatic productivity. This raises the opportunity to enclose parts of these floodwater areas to produce a crop of specifically stocked aquatic organisms aside from the naturally occurring ‘wild’ species that are traditionally fished and are not affected by the culture activity, resulting in more high-quality, nutrient-dense food production and enhanced farm income for all stakeholders, notably the poor. The WorldFish Center and its national partners recently tested the concurrent rice-fish culture in the shallower flooded areas and the alternating rice-fish culture in the deep-flooded areas of Bangladesh and Viet Nam through a community-based management system. Results indicate that community-based fish culture in rice fields can increase fish production by about 600 kg/ha/year in shallow flooded areas and up to 1.5 t/ha/year in deep-flooded areas, without a reduction in the rice yield or wild fish catch.

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South Africa- Shifting livelihoods, Viet Nam-Strengthening livelihoods, Chile - gains and challenges, Uganda- making changes possible, Maritza Mena from Costa Rica, Ground-breaking gender indicators, You tube resources

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Ecological study on Kolahy and 'flab estuaries were carried out during 1996-1997. Water and sediment sampling was done seasonally. In order to study the physical and chemical characteristic of the water, various animal fauna from different material niches including planktons and fish from water, benthousi from the sediment , and surface living animal such as Arthropod (Crabs) and Waterbirds were identified. I he result shoved, that water salinity of both estuaries was the same as the general salinity existing its the Persian Gulf water, and its variation is same IN those waters Minimum water salinity in both estuaries are seen during Bahairdan or early winter mooth(Jaa.), which is about 31ppt and Maximum is during .rirldlun.) or summer mouth at about 19 ppt. Dissolved otygen and pH are slime as the general Persian Gulf waters., Dissolve Oxygen being directly associated to temperature and its fluctuation is between 7- Sing/I and pH between 7.5-LS. The animals of both estuaries are almost similar having a sal factory species diversity . The birds of the region are often seasonal migrants , the maximum population of which occurs in winter season and the minimum during summer month. Nam coverage is richer in Tiab than Kolahy estuary, where in Kolahy a signal Mangrove tree is in exigence. 'Ile total coverage of Mangrove forest in Tiab is estimated about -29 hec.Both estuaries are included with in the international Ramsar Convention sites in 1971. Due to national importance of these estuaries inproviding refugee for various birds species and also hinting grounds and access traffic for local fishing vehicles, Actiog as an important access for various inhabitancy living with these area of the Persian Gulf. Due to importance or prawn aquacultur for the economical well being of local inhabitance, these areas provide a suitable grandees for prawn production. I-test statistics show, there are no significant difference among various invertebrate and vertebrate animals. In over all out look 21) phytoplankton genera, 21) zeoplankton genera 17 miafauna and 32 roaerofauna genera , 11 different species Carcineacearions and 119 species of walerbirds were identified with in the Tiab and Kolahy estuariesregioos. The X statistic show that the animal density is directly associated to season. Where density of miofauna and maerofauna in both estuaries are in maiticrourn during summer and the minimums existing during the winter season. In addition the bentic invertebrate population density in closlly association to birds population density since , the later, feeds on the former animals. Where the increasing in bird population density during the winter season, the bentic invertebrate animal population density decreases. The over all trend of animal population density in winter tend to increased towards the summer seasons, which this is due to climatic conditions of the region. The bird population on the contrary to other animals of both estuaries tend to increase from summer towards the winter seasons and which this bird population density is in maximum in winter with in the region.

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An improved technique for transferring large area graphene grown by chemical vapor deposition on copper is presented. It is based on mechanical separation of the graphene/copper by H2 bubbles during H2O electrolysis, which only takes a few tens of seconds while leaving the copper cathode intact. A semi-rigid plastic frame in combination with thin polymer layer span on graphene gives a convenient way of handling- and avoiding wrinkles and holes in graphene. Optical and electrical characterizations prove the graphene quality is better than that obtained by traditional wet etching transfer. This technique appears to be highly reproducible and cost efficient. © 2013 American Institute of Physics.

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A model of the graphene growth mechanism of chemical vapor deposition on platinum is proposed and verified by experiments. Surface catalysis and carbon segregation occur, respectively, at high and low temperatures in the process, representing the so-called balance and segregation regimes. Catalysis leads to self-limiting formation of large area monolayer graphene, whereas segregation results in multilayers, which evidently "grow from below." By controlling kinetic factors, dominantly monolayer graphene whose high quality has been confirmed by quantum Hall measurement can be deposited on platinum with hydrogen-rich environment, quench cooling, tiny but continuous methane flow and about 1000°C growth temperature. © 2014 AIP Publishing LLC.

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Placocheilus is re-diagnosed on the basis of oromandibular structures compared to those of closely related groups. It is represented in China by three species restricted to Yunnan, namely P. caudofasciatus from the Tengtiaohe River (Nam Na), P. cryptonemus from the Nujiang Rive ( upper Salween River basin), and P. robustus, herein described as a new species from the Yuanjiang River ( Red River basin). P. robustus n. sp. is differentiated from its congeners in having a stout caudal peduncle ( depth 72.4-82.5% of its length) and the medium-sized scaleless midventral region of belly extended slightly beyond halfway from the pectoral- to pelvic-fin origin. It is further distinguished from P. caudofasciatus in having a coarsely crenulated rostral fold with 18-23 indentations on its distal margin and a smaller mental adhesive disc ( length 66.7-71.4% of its width and 37.0-43.1% of the head length).

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本研究重点对云南哀牢山、无量山、永德大雪山以及老挝 Nam Kan 保护区西黑冠 长臂猿(Nomascus concolor)的鸣叫特征进行了分析研究,以探讨长臂猿鸣叫个体特异性 的发生机制及其在地理种群区分或亚种地位划分中的意义;同时对哀牢山平河西黑冠长 臂猿栖息地乔木结构进行了样方调查,揭示西黑冠长臂猿高海拔栖息地的乔木结构特 征,为后续行为学研究提供基础生态数据。 研究表明,云南省哀牢山平河(N 24°20′09.5″, E 101°17′16.1″, 海拔2600m)的黑 长臂猿栖息地有乔木57 种隶属于23 科37 个属;木质藤本植物9 种隶属于6 科8 属。 优势科主要为杜鹃花科(Ericaceae)、木兰科(Magnoliaceae)、山茶科(Theaceae)和 壳斗科(Fagaceae)植物。乔木的多样性指数、均匀度指数在沟底明显降低,而乔木1 层和2 层所占的比例以及木质藤本的平均多度均随着坡位的下降而升高。与其他地区的 长臂猿相比,哀牢山黑长臂猿的活动高度较低(10—22m),果实性食物种类较少。 西黑冠长臂猿的雄性鸣叫包括Boom 音节、aa 音节、弱调节音节、强调节音节和 coda 音节,Boom 音节只是一单独的条带状音节,结构最简单也最稳定;aa 音节、弱调 节音节、强调节音节和coda 音节的稳定性则呈现出依次增大的趋势。强调节音节和coda 部分的稳定性在总体没有显著差异,但在某些变量上coda 音节比强调节音节有显著更 高的稳定性。在此基础上,重点基于对coda 音节的分析,发现同一地点不同群体的雄 性西黑冠长臂猿个体之间存在非常显著的鸣叫特异性,并且同一地点不同群体的雄性个 体之间鸣叫的差异,显著高于不同地点间雄性个体间鸣叫的差异。这一发现表明西黑冠 长臂猿很有可能在有意识地通过鸣叫声音的调节,来增加与邻近群体间鸣叫的差异性, 并依靠这一行为识别邻近群的成年个体和陌生个体或新成年的未配对个体,这对具领域 性、配对的长臂猿来说具有显著的生态适应意义。基于对西黑冠长臂猿所有4 个亚种雌 雄个体鸣叫的逐步判别分析,结果表明西黑冠长臂猿明显分为3 个类群:1) 指名亚种 (N. c. concolor)和景东亚种(N. c. jingdongensis)为同一类群;2)滇西亚种(N. c. furvogaster)类群;3)老挝亚种(N. c. lu)类群,综合我们及前人的研究结果,我们认 为老挝亚种与其它三个亚种之间很可能已经达到了亚种分化的水平,滇西亚种也是如 此,但其有效性还值得进一步研究和探讨,而指名亚种和景东亚种间可能还没有达到亚种分化的水平。

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大气CO2浓度升高可以通过植物间接影响土壤生态系统。土壤生态系统的结构和功能改变将影响有机质矿化和营养物质循环,进而可能对CO2浓度升高产生正反馈或负反馈。微生物是土壤生态系统的主体,在对CO2浓度升高的反馈中起着至关重要的作用。本研究以开顶箱系统为平台,采用微生物分子生态学技术和现代酶学技术,通过对长期接受500 ppm CO2的红松幼树、长白赤松幼树和蒙古栎幼树非根际土壤连续两个生长季的测定,系统研究了高浓度CO2对温带森林土壤微生物群落的生物量和微生物活性的影响,检测了土壤微生物群落的结构和功能以及土壤化学性质变化,主要结论如下: (1)高浓度CO2处理提高了土壤有机碳含量。与对照组相比较,红松幼树土壤有机碳含量提高9.4%;长白赤松幼树土壤提高0.6%;蒙古栎幼树土壤提高1.3%。 (2)高浓度CO2处理使土壤磷酸酶(phosphatase)、几丁质酶(1,4-β-acetylglucosaminidase, 1,4-β-NAG)和多酚氧化酶(phenol oxidase)活性发生了显著变化,高浓度CO2使红松土壤 1,4-β-NAG活性提高7-25%,长白松土壤1,4-β-NAG平均活性降低14%,蒙古栎土壤1,4-β-NAG平均活性提高31%。 同时研究还发现,过氧化物酶(peroxidase)和多酚氧化酶(phenol oxidase)活性与微生物量碳和微生物量氮呈显著的正相关。相关分析还显示,土壤湿度与1,4-α-葡萄糖苷酶(1,4-α-glucosidase)活性、 微生物生物量碳和微生物生物量氮呈显著的正相关。 高浓度CO2在不同程度上改变了土壤转化酶活性和脱氢酶活性。高浓度CO2显著提高了红松和长白赤松土壤硝化酶活性;而显著降低反硝化酶活性。 (3)研究发现三种树土壤的真菌和细菌群落存在着季节性演替,并且高浓度CO2熏蒸处理使真菌群落结构发生了显著的变化,表现为一些种群优势度下降,另一些升高。虽然,细菌群落没有如真菌群落变化的明显,但研究中也发现高浓度CO2的确使个别细菌种群的优势度发生了显著改变。 亲缘关系与Calocybe carnea,Magmatodrilus obscurus密切的真菌是红松土壤优势种群,与Humicola fuscoatra关系相近的是长白松土壤的优势种群,并且此三种真菌的季节性变化不显著。研究发现高浓度CO2使红松土壤中亲缘关系与Pachyella clypeata,Cochlonema euryblastum,Lepiota cristata,Eimeriidae sp., Trichoderma sp.相近的种群的丰富度显著提高,使蒙古栎土壤中亲缘关系与Serendipita vermifera,Calocybe carnea种群丰富度显著下降,使蒙古栎土壤中与Candida sp.,Magmatodrilus obscurus和Pachyella clypeata亲缘关系密切种群的丰富度显著提高。 (4)三种幼树叶的原位分解培养429天结果显示,红松和长白松凋落物的β-葡萄糖苷酶(1,4-β-glucosidase)和木糖苷酶(1,4-β-xylosidase)活性随着分解而逐渐增加,而这两种酶在蒙古栎凋落物分解过程中保持相对恒定;高浓度CO2显著影响叶凋落物分解磷酸酶(phosphatase),纤维二糖酶(cellobiohydrolase), 几丁质酶(1,4-β-NAG),多酚氧化酶(phenol oxidase)和过氧化物酶(peroxidase)的活性。研究发现,凋落物的生物化学性质变化能引起分解的微生物群落发生变化,进而引起分泌的胞外酶活性变化,科学印证了大气CO2浓度升高“通过影响凋落物质量进而影响分解叶凋落物的微生物群落的结构和功能”的猜测。 不同凋落物之间酶活性差异显著,真菌和细菌群落结构也显著不同。序列与Hyphodiscus hymeniophilus亲缘关系密切的真菌和亲缘关系与Verrucomicrobia bacterium密切的细菌是长白松凋落分解的最优势种群,序列与Lophium mytilinum亲缘关系密切的真菌是红松凋落分解的最优势种群。 另外,研究还发现,高浓度CO2使参与分解红松凋落物Beta proteobacterium OS-15A亲缘关系相近的细菌种群和与Azospirillum amazonense亲缘关系相近的种群丰富度显著降低;使与Luteibactor rhizovicina亲缘关系相近的种群和与Luteibactor rhizovicina亲缘关系相近的种群显著提高。高浓度CO2使定殖于长白松凋落物上Hyphodiscus hymeniophilus亲缘关系相近的种群和与Bionectria pityrodes亲缘关系相近的种群显著提高,而使与Neofabraea malicorticis亲缘关系相近的种群和与Hyphodiscus hymeniophilus亲缘关系相近的种群显著下降。

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复合肥长效添加剂是将脲酶抑制剂、硝化抑制剂、磷活化剂有机结合,利用其协同作用比单一抑制剂使肥料具有更长供肥期和更高利用率,达到一次性投肥免追肥的目的。这是提高作物产量和提高化肥利用率的有效手段之一,应大力推广在复混肥中添加这种长效添加剂(NAM)。

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A novel synthetic approach to biodegradable amphiphilic copolymers based on poly (epsilon-caprolactone) (PCL) and chitosan was presented, and the prepared copolymers were used to prepare nanoparticles successfully. The PCL-graft-chitosan copolymers were synthesized by coupling the hydroxyl end-groups on preformed PCL chains and the amino groups present on 6-O-triphenylmethyl chitosan and by removing the protective 6-O-triphenylmethyl groups in acidic aqueous solution. The PCL content in the copolymers can be controlled in the range of 10-90 wt %. The graft copolymers were thoroughly characterized by H-1 NAM, C-13 NMR, FT-IR and DSC. The nanoparticles made from the graft copolymers were investigated by H-1 NMR, DLS, AFM and SEM measurements. It was found that the copolymers could form spherical or elliptic nanoparticles it? water. The amount of available primary amines on the surface of the prepared nanoparticles was evaluated by ninhydrin assail, and it can be controlled by the grafting degree of PCL.

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The reaction of trivacant precursor Nag [A-PW9O34] . 19H(2)O with Ti(SO4)(2) affords the novel dimeric, di-Ti-IV-substituted tungstophosphate K4Na6[alpha-1,2-PW10Ti2O39](2) . 14H(2)O. The X-ray structural determination shows the dimeric, anhydride structure was formed by two Ti-O-Ti bonds linking two di-titanium-substituted Keggin anion [alpha-1,2-PW10Ti2O40]. It was also characterized by elemental analysis, TGA, FT-IR and U-V-vis spectroscopies.

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Glaciers in west China are the sources of the major great rivers in Asia, and the solid water resources are crucial to China and South Asia. Black carbon (BC) results in very complex climate effects not only in the atmosphere, but accelerates the melting after its deposit on the surface of snow/ice. As the main distributed area of glaciers in China, the Tibetan Plateau (TP) and Xinjiang region are abutted by South Asia, Central Asia, and Russia, and east China, and the atmospheric environment would be influenced by the BC emitted from these regions. Whereas, the BC’s temporal and spatial distributions for concentration in the mid and top troposphere in west China, its transport, and its radiative forcing after deposited on the snow/ice surface are not well understood at the present. In the field, we collected samples from surface snow, snow pits, ice core, and aerosol in the glaciers, analyzed BC content mainly by the thermo-oxidized method in the laboratory, and discussed temporal and spatial distributions for BC concentrations in glaciers, the transport, and its impacts on the environment. Several conclusions were derived as follows: 1_Spatial distribution and the impact on albedos for BC concentrations in snow/ice: the BC concentrations in the surface snow for the investigated glaciers could be placed in areas, the Tianshan Mountains > the central TP > the Pamirs > the Qilian Mountians > the Himalayas. This distribution could be attributed to the elevation of the glaciers, the topography of the TP, and more regional emissions. Probably significant impacts on the albedos of the glacier surface could be caused by BC deposits, and the estimated reduced albedos on the glaciers are 9.8% (the Zhadang glacier), 8.7% (the Miao’ergou Riverhead No.3 glacier), and 6.8% (the Kuitun River Haxilegen No.48 glacier), and 6.2% (the Dongkemadi glacier), and 5.3% (the La’nong glacier), and 4.2% (the Muztagata glacier), etc. 2_The temporal variance of BC concentrations in ice of the East Rongbuk Glacier (ERG) and its climatic implications: major cations and anions (e.g., SO42- and Ca2+) concentrations in aerosols during summer monsoon seasons showed their close relationships with the sources of air masses, in which the variance of SO42- concentrations suggested the atmospheric environment over the ERG was significantly influenced by the aerosols from South Asia. BC record based on an ice core suggested its deposit was dominantly transported by monsoons in summers and by westerlies in other seasons, and the BC from South Asia in summers dominated the varying trend of its concentrations in the ice core and caused higher concentrations in summers than those in other seasons. In the past 50 yrs, BC concentrations showed fluctuations, whereas showed an increasing tread in the most recent decade, and exceeded 50 μg kg-1 in the summer of 2001; correspondingly, the radiative forcing caused by BC showed an increasing trend since 1990s, and exceeded 4.5 W m-2 in the summer of 2001. 3_Cabonaceous aerosols in the Nam Co region: organic carbon (OC) concentration accounted for ~95% and BC for ~5% in the total carbonaceous aerosol concentration, which was significantly influenced by summer precipitations. OC was dominantly derived from fossil fuel burning and BC from both fossil fuel and biomass burning. Trajectory analysis and aerosol optical depth suggested the atmospheric environment in the Nam Co region was most probably influenced by the emissions from South Asia. The potential source regions of air pollutants in the Nam Co regions in summers might be Bangladesh and east India, and in winters might be the Indo-gangetic basin. The scavenging ratio of atmospheric BC by rainfalls was less than those at other sites. West China is a less-developed region for industry, where BC concentrations in the atmosphere and snow/ice could be significantly influenced by the emissions from the abutted regions with rising industries (South Asia, Central Asia, and Russia). For example, snow/ice BC concentrations in the glaciers of the Parmirs, the Tianshan Mountains, and the Qilian Mountains in the northeast margin of the TP might be more influenced by the emissions from Centrial Asia (transported by the westerlies), those in the glaciers of the Himalayas might be more influenced by the emissions from South Asia (transported by the monsoons and the westerlies), and atmospheric carbonaceous aerosols might also be more influenced by the emissions from South Asia (transported by the monsoons and the westerlies). The BC concentrations in some glaciers might cause significant impacts on the albedos for the glaciers, and therefore enhanced the radiative forcings, for example, the ERG. The research on the relationships among atmospheric and snow/ice BC and its radiative forcing, variance of snow cover, mass balance of glaciers, and climate forcing would be needed in future.