949 resultados para G-f-20


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Studies have been carried out in glasses containing Fe2O3, V2O5, and Fe2O3 + V2O5. Mossbauer studies in the ZnO-B2O3-Fe2O3 system show that iron is present as Fe3+ with tetrahedral coordination and that the isomer shift and the quadrupole splitting decrease with increase of Fe2O3 Content; similarly, the isomer shift and quadrupole splitting are also found to decrease with increasing ZnO. On the other hand, in the Na2O-ZnO-B2O3-Fe2O3 system, the isomer shift increases with Na2O or ZnO while the quadrupole splitting is fairly insensitive. Electron paramagnetic resonance in the ZnO-B2O3-Fe2O3 system shows signals at g = 4.20 and 2.0, whose intensity and linewidth show strong dependence on Fe2O3 content. In the ZnO-B2O3-V2O5 system, electron paramagnetic resonance shows that vanadium is present as the vanadyl complex, and the hyperfine coupling constants, A(parallel-to) and A(perpendicular-to) decrease with increasing V2O5 content; on the other hand, g(parallel-to) decreases and g(perpendicular-to) increases slightly, indicating an increase in tetragonal distortion. Zinc borate glasses containing Fe2O3 + V2O5 do not show the hyperfine structure of V4+ due to the interaction between Fe3+ and V4+

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El trabajo de investigación consistió en el establecimiento del cultivo de plátano variedad CEMSA ¾ en la parcela agroecológica de cultivos perennes del Departamento de Producción Vegetal (DPV) de la Universidad Nacional Agraria, ubicada en el km 12 ½ carretera norte , Managua. Se aplicaron tres dosis de vermicompost (15, 30 y 45 t ha - 1 ) equivalente a 6, 12 y 18 kg planta - 1 con fertilización foliar complementaria : enraizador ( 50 g ) , completo 20 - 20 - 20 ( 40 g ) y sulfato de magnesio ( 20 g) por cada 20 l de agua. Se evaluaron variables de crecimiento: Altur a de la planta (m), Diámetro del pseudotallo (cm), Número de hojas funcionales a cosecha, Área f oliar (m 2 ) y variables de rendimiento: Peso del racimo (kg), Número total de manos, Número de dedos del racimo a cosecha, Diámetro de los dedos (cm ) , Diámetro d el raquis (cm) , Largo de los dedos (cm) y Largo del racimo (cm) . Se estableció en un diseño de parcelas apareadas formadas por tres franjas, con una población inicial de 180 plantas a una distancia de 2 m entre planta y 2 m entre surco. El tratamiento a 2 b 1 (30 t ha - 1 + enraizador) , obtuvo los mejores resultados en las variables altura de planta (2.1 m), diámetro del pseudotallo (105 . 94 cm) y número de hijos (3.8), no así en la variable área foliar donde el tratamiento a 1 b 2 (15 t ha - 1 + enraizador + completo 20 - 20 - 20) fue el que mostró mayor área foliar (8 .54 m²). Los rendimientos obtenidos en el tratamiento a 2 b 1 (30 t ha - 1 + enraizador) presentaron mejor resultado en las variables peso de racimo (10.46 kg), n ú mero de manos (9.06) y número de dedos (46.59). E n el diámetro del dedo se destacó el tratamiento a 3 b 3 (30 t ha - 1 + enraizador + completo 20 - 20 - 20 y sulfato de magnesio) con 4.58 cm y 4.37 cm respectivamente. En el largo del dedo se destacaron los tratamientos a 1 b 1 (15 t ha - 1 + enraizador) y a 1 b 3 (15 t ha - 1 + enraizador + completo 20 - 20 - 20 y sulfato de magnesio) con 30.13 cm y 24.36 cm respectivamente. El análisis económico demostró que el tratamiento que present ó mayor rentabilidad es el a 2 b 1 en base a la relación beneficio - costo se genera una ganancia de C$ 1 .17 por cada córdoba invertido

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Este estudo teve como objetivo principal utilizar os teores de elementos-traço e análise isotópica de Pb (204Pb,206Pb,207Pb,208Pb) como ferramentas na caracterização da poluição da Baía de Sepetiba-RJ. As coletas de sedimento superficiais de fundo foram realizadas em três campanhas, em novembro de 2010, no setor oeste da Baía de Sepetiba RJ. A malha amostral é composta por 66 amostras (BSEP 001 a BSEP 066) coletadas com busca-fundo Van Veen. O pré-processamento das amostras ocorreu no Laboratório Geológico de Preparação de Amostras do Departamento de Geologia da Universidade do Estado do Rio de Janeiro. A digestão parcial das amostras de sedimento (< 0.072 mm) para obtenção do teor parcial dos elementos-traço (Ag, As, Cd, Co, Cr, Cu, Li, Mn, Ni, Pb, Sr, U, Zn) e de isótopo de Pb (lixiviação) foi executada no Laboratório de Geoquímica Analítica do Instituto de Geociências da UNICAMP e a leitura foi executada através do ICP-MS. Já as análises das concentrações totais dos elementos-traço (inclusive, Hg) e de isótopos de Pb (dissolução total) foram realizadas no laboratório ACTLABS (Ontário-Canadá) através do ICP Varian Vista. As leituras isotópicas foram feitas somente nas amostras que apresentaram concentrações parciais de Pb, acima de 0,5 g/g, totalizando 21 estações. Pôde-se constatar a existência de um enriquecimento de elementos-traço no setor oeste da Baía de Sepetiba. As médias dos teores totais de Ag (0,4 g/g), Cd (0,76 g/g), Cu (62,59 g/g), Li (43,29 g/g), Ni (16,65 g/g), Pb (20,08 g/g), Sr (389,64 g/g) e Zn (184,82 g/g) excederam os limites recomendados ou valores naturais. Isto pode ser reflexo da influência antrópica na região, principalmente relacionada à atividade de dragagem e à permanência dos resíduos de minério da desativada companhia de minério Ingá, na Ilha da Madeira. Os mapas de distribuição da concentração dos metais-traço destacaram a presença de vários sítios de deposição ao longo do setor oeste da baía de Sepetiba, com destaque para a região entre a porção centro oeste da Ilha de Itacuruça e o continente; Saco da Marambaia e Ponta da Pombeba; e porção oeste da Ponta da Marambaia. As razões isotópicas 206Pb/207Pb da área estudada variaram entre 1,163 a 1,259 para dissolução total e 1,1749-1,1877 para técnica de lixiviação, valores considerados como assinaturas de sedimentos pós-industriais ou comparados à assinatura de gasolina. Ainda sobre a técnica de lixiviação, destaca-se que os sedimentos superficiais do setor oeste (206Pb/207Pb: 1,1789) da baía de Sepetiba apresentaram uma assinatura uniforme e menos radiogênica do que setor leste (206Pb/207Pb: 1,2373 e 1,2110) desta baía. Através da assinatura isotópica de Pb encontrada nesta região é possível destacar a pouca contribuição das águas oceânicas para esse sistema, entretanto, a circulação interna intensa das águas da baía permite a homogeneização destas. O emprego destes tipos de ferramentas no monitoramento ambiental da área mostrou-se bastante eficiente, sendo importante a continuidade desta abordagem de pesquisa a fim de auxiliar na implementação de um plano de manejo local.

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Studies were conducted to evaluate the quality of hilsa fish during icing and freezing storage at -20°C by determining organoleptic and bacteriological aspects. The fishes stored in ice were organoleptically in acceptable condition 2 for 20 days. The bacterial load in muscles of 4 days ice stored fish was 2.5x10² CFU/g which gradually increased up to 1.8x10⁵ CFU/g after 20 days when the fishes were organoleptically in acceptable condition. The keeping qualities of different days of ice stored fishes were also evaluated during their subsequent frozen storage at -20°C. Both 4 and 7 days of ice stored fishes were organoleptically in acceptable condition up to 48 weeks but the highest degree of freshness was found for fish stored in ice for 4 days before freezing at -20°C. The result indicates that the longer is the duration of ice storage before freezing, the shorter is the shelf life of the fish. The initial bacterial load prior to freezing of the 4 and 7 days of ice stored samples were 2.5x10³ CFU/g and 3.8x10⁴ CFU/g, respectively which reduced to 2.21x10² CFU/g and 2.38x10² CFU/g, respectively at the end of the 24 weeks of frozen storage. However, after 40 weeks the bacterial load in the frozen stored sample fell below the detection level.

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本研究建立了沉积物中氯化石蜡(CPs)的分析方法,对莱州湾和该区域主要河流的表层沉积物中多氯萘(PCNs),多溴联苯醚(PBDEs)和CPs进行了分析,获得了他们在研究区域的含量水平、空间分布和单体分布模式,并初步探讨了它们在环境中的来源和迁移规律,估算了这三类污染物在莱州湾表层沉积物中的储量,初步评估了莱州湾沿岸的工业排放与人类活动对海洋生态环境的影响。 莱州湾海洋和河流沉积物PCNs的含量分别为65-470 pg/g dw,52-5100 pg/g dw,平均值分别为260 pg/g dw,1100 pg/g dw。莱州湾沉积物中PCNs的含量较低,与发达国家的背景值相当,主要河流沉积物与其他地区的近海、海湾、湖泊沉积物的含量相当。该区域的PCNs主要以5-Cl和6-Cl为主,为工业来源,主要受化工行业的影响。石化工厂热过程产生的低氯组分可能也是该区域PCNs的一个重要来源。莱州湾的PCNs主要来自水体颗粒的输入,而大气沉降来源的贡献不明显。 河流沉积物ΣPBDEs(不包括BDE-209)的含量分别为0.01- 53 ng/g dw,BDE-209的含量为0.74- 280 ng/g dw,平均值分别为4.4 ng/g dw,51 ng/g dw。在组成上,BDE-209占绝对优势,比低溴代BDEs高1-2个数量级,这是由于我国市场上十溴联苯醚是最主要的溴代阻燃剂。ΣPBDEs与亚洲一些地区含量相当,比北美和欧洲一些地区要低;BDE-209含量含量高出北美和欧洲一些地区,处于较高的水平。河流沉积物中BDE-47与-99,BDE-183与-153、-154具有很好的相关性,而且这几种单体质量分数相当,说明莱州湾区域存在五溴和八溴两种工业BDE阻燃剂来源。海洋沉积物中ΣPBDEs的含量为nd- 0.66 ng/g dw,平均值为0.32 ng/g dw,处于较低水平,BDE-209的含量为0.66- 12 ng/g dw,平均值为5.1 ng/g dw,与欧美一些地区相当,主要来自水体颗粒的输入。 本研究用电子捕获低分辨质谱(ECNI-LRMS)建立了沉积物中CPs的分析方法。该方法基于ECNI质谱对SCCP的响应与其氯含量在一定范围内呈线性关系的特性,建立SCCP的总响应因子与氯含量的工作曲线,从而建立定量方法。重点改进了传统方法中由于SCCP标准品和样品中氯含量不同所造成的响应因子的差别,不再要求标准品的含氯量与样品一致,从而提高了SCCP的分析效率与方法准确性。实验发现,当SCCP的实际氯含量在51%-63%之间时,二者线性关系良好(r2>0.96)。用不同氯含量的标准参考品测试,误差为8%-43%。仪器检测限和方法检测限分别为25-400 μg/L,20 ng/g。类似地,建立了中链氯化石蜡(MCCP)的分析方法,工作曲线的实际氯含量范围为44-57%,仪器检测限40-600 μg/L,方法检测限为6 ng/g。通过对比样品与标准品的峰形特征,严格控制保留时间来辨别SCCP与MCCP,实验证明由于二者叠加导致的误差:SCCP为8%,MCCP为14%,总体来说,用该方法得到的CPs数据是可靠的。本文所使用的净化方法能实现CPs与大部分有机氯化合物的分离。 用该方法对莱州湾的沉积物的CPs进行定量,除了两个河流样品MCCP的计算含氯量低于工作曲线以外,其他样品的SCCP和MCCP的计算氯含量都在工作曲线的范围之内。河流沉积物中SCCP和MCCP的含量分别为1-1200 ng/g dw,1-3300 ng/g dw,MCCP/SCCP均值为1.2;含量分布变化较大,一些河段受到工业排放的影响,CPs浓度高出均值1-2个数量级,MCCP/SCCP值也显著高出平均值。莱州湾区域大部分河流的CPs含量与欧洲、北美和日本一些地区相当,而一些受到点源污染的河段则处于较高的水平。河流中SCCP的质量分布在不同的站位不一样,在受到点源影响的样品中,C13的质量分数明显增大,占优势地位,可能是由MCCP携带的SCCP组分所致。MCCP的质量分布在河流和海洋中没有区别,都是C14占绝对优势。从氯取代的组分来讲,所有样品都是以6-8氯取代为主。海洋沉积物中SCCP和MCCP的含量分别为3-18 ng/g dw,1-13 ng/g dw, MCCP/SCCP均值为0.68,显著低于河流沉积物;SCCP的质量分布较为一致,都是以C10和C11为主。研究发现莱州湾区域SCCP与MCCP来源相似,但迁移规律有的不同。海洋环境中的MCCP可能主要来自水体颗粒的输入,而溶解态输入也是海洋环境中SCCP的重要来源。 对这三类污染物在莱州湾表层沉积物中的储量估算得到PCNs、ΣPBDEs、BDE-209、SCCP和MCCP在莱州湾表层0-10 cm沉积物中的储量分别为0.20t,0.25t,3.95t,6.52t,4.30t。拥有10%的渤海海域面积的莱州湾ΣPBDEs和BDE-209的储量分别占渤海海区总量的18-23%,18-32%,远远超过渤海的平均值。

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Baseline survey and Participatory Rural Appraisal (PRA) during January 2003 to December 2004 on the fishing community revealed that unregulated fishing, use of destructive fishing gears, poaching of fishes, difficulties encountered in enforcing fisheries regulation and the helplessness of fishers to find alternative sources of income during banned fishing period (June to October) were the major management problems. CBFM (Community Based Fisheries Management) system as an alternative management strategy has been introduced to ensure active participation of the target group-the poor fishers living around the beet who were previously deprived to get access to the beet. Establishing a leasing system for controlled access, ensuring greater user-group participation through equitable distribution of all resource benefits among members, attempting to enforce penalties for illegal fishing linked with surprise checks to enforce management regulations are some of the recent steps taken by the BMC (Beel Management Committee). Chapila fish intake by the community was 31.25 g/head/day before stocking the beel by carp fingerlings. After stocking, they consumed chapila as fish protein from 8.33 g to 20.8 g/head/day during the fishing season (November to May) indicating that due to introduction of carp fingerlings, chapila production has been decreased in 2003-2004. About 77.5% families around the beel were found to be dependent directly and/or indirectly on chapila and other indigenous fishes of the beel for their livelihood, through fishing, marketing and other activities like net and boat preparation and nets mending etc. Particularly fishers' families were found to face serious problem during non-fishing period like June to October for their livelihood. Analyzing the present research result it was also observed that other than declination in biodiversity, the fishing pressure on promising chapila of the beel was found high and that is why the production of chapila has also been decreased. To get sustainable chapila production from the heel, it is suggested to ensure successful spawning and recruitment as juveniles, and hence the chapila should be undisturbed during its breeding period from March to July, and fishing pressure on the same species needs to be reduced for obtaining sustainable fish production.

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An 8 weeks feeding trial was conducted in a static indoor rearing system to investigate protein to energy ratio (PIE ratio) in walking catfish Clarias batrachus. Six fishmeal based diets of two protein levels (25 and 35%), each with three lipid levels (5, 10 and 15%) resulted in P/E ratios ranging from 13.57 to 21.97 mg protein kJˉ¹ gross energy (GE) were fed to 50 fish in triplicate. Fish were fed 6% of their body weight three times per day adjusted fortnightly. Significantly higher (p<0.05) growth rates in terms of weight gain, % weight gain and specific growth rate (SGR) were evident in fish fed with higher protein diet. The highest growth rate was found by fish fed 35% protein, 17.06 kJˉ¹GE with a P/E ratio of 20.55 mg protein kJˉ¹GE. Significantly better (p<0.05) feed conversion ratio (FCR) was also evident in fish fed with higher protein diet and best FCR was found by fish fed 35% protein, 10% lipid, 17.06 kJˉ¹GE with a P/E ratio of 20.55 mg protein kJˉ¹GE. Significantly indifferent (p>0.05) values of protein utilisation were found in between the both (higher and lower) protein diets. Higher lipid deposition (p<0.05) in whole body was observed with increasing dietary lipid level at each protein diet and as higher (p<0.05) for the lower protein diets. The study reveals that C. batrachus performed best the diet containing 35%, 17.06 kJ gˉ¹ and 20.55 mg protein kJ gˉ¹ GE protein, gross energy and P/E ratio respectively.

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通过对培养时间、培养温度、刀豆蛋白A(ConA)质量浓度和鳗鲡血清质量分数4个参数的测定,确定欧洲鳗鲡(Anguilla anguilla)外周血淋巴细胞转化试验四甲基偶氮唑(MTT)法的实验条件。结果表明,在培养时间为42-90 h,培养温度分别为15.0℃、20.0℃、25.0℃和30.0℃时,细胞培养液中ConA质量浓度分别为0、10μg/mL、20μg/mL和30μg/mL,鳗鲡血清质量分数分别为0、5%、10%和15%时,淋巴细胞于20.0℃、含10μg/mL ConA,10%鳗鲡血清的RPMI

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氢化物发生-高频感耦等离子体原子发射光谱分析(HY-ICP-AES),由于它的灵敏度高和多元素同时分析等特点,近年来受到越来越多的科学工作者的重视。本文对HY-ICP-AES的原理、发展及应用作了比较详细的综述,并根据氢化物元素和非氢化物元素同时测定的实际要求,提出了一种新型的氢化物发生-雾化系统。文献上已报导了两种氢化物元素和非氢化物元素同时测定的方案,并取得了令人满意的结果。但在这些方案中,存在一些问题需要解决,而且装置比较复杂,操作也比较麻烦。在我们的氢化物发生-雾化系统中,用一个同心玻璃雾化器将待测的样品溶液雾化,细雾滴形成气溶胶,较大液滴被收集在一个玻璃槽中,硼氢化钾溶液用蠕动泵从玻璃槽底部送入,与收集的样品溶液混合并发生化学反应,产生挥发性的共价氢化物。生成的气态氢化物和样品气溶胶以及载气一起进入等离子体,因而可以进行氢化元素和非氢化物元素的同时测定。砷、锑、硒和碲的检出限分别为0.0075,0.0006,0.008,0.003,0.002 μg/ml,比传统的气动雾化方法得到的检出限好20-30倍。而对非氢化物元素,检出限可与双简雾室雾化相当。本系统进样量小(约2 ml),且样品的利用率大为提高,有利于小量样品的分析。但由于进样量较小,限制了灵敏度的进一步提高。本系统的另一个特点是不仅可以用于氢化物元素和非氢化物元素的同时测定,而且在需要的情况下,不需拆换雾化装置,不需灭火,即可在1-2分钟内转变成为普通的测定非氢化物元素的雾化系统。只要将蒸馏水取代硼氢化钾溶液把收集样品溶液的玻璃槽冲洗干净,即可作为普通的雾化系统之用。我们用这种氢化物发生-雾化系统研究了等离子体功率、载气流量、观测高度、样品介质酸度、硼氢化钾溶液和流量对待测元素信号强度、信-背比和检出限的影响以及硼氢化钾溶液的稳定性和硼氢化钾的引入量对等离子体稳定性的影响等。我们还研究了几种共存干扰元素对氢化物形成的干扰情况。为了消除或减小共存元素对氢化物生成过程的干扰,我们试验了EDTA,8-羟基喹啉,氨三乙酸,硫脲等对干扰元素的掩蔽作用,最后选EDTA作为掩蔽剂,对消除或减小共存元素的干扰起了明显的作用。我们用本雾化系统分析了一种甜菜颗粒粕样品和桃叶82301标准参考物质。分析结果与其它方法或标准值比较吻合。在甜菜颗粒粕样品的分析中,我们发现基体中大量镁、钙对砷等低含量元素的光谱干扰比较严重,利用元素间干扰比不能予以准确扣除。我们用标准和样品的基体相匹配的方法解决了镁、钙的光谱干扰问题。

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采用微波消解、电感耦合高频等离子体原子发射光谱(ICP-AES)的方法,对62份不同小麦品种(系)中锌、铁、铜、钙、钠和钾的含量进行了测定。同时利用红外线品质测定仪对主要品质指标粗蛋白、湿面筋、沉降值进行了测定。结果表明,不同小麦品种(系)中各种矿质元素的含量存在差异,2006年小麦品种中铁含量变幅为18.55-58.19 ug/g,平均为30.83ug/g ,最高与最低的相差39.64ug/g;锌含量变幅为5.70-25.80 ug/g,平均为15.13ug/g ,最高与最低相差20.10ug/g。2008年小麦品种(系)中铁含量变幅为16.68-52.25 ug/g,平均为30.10ug/g,最高与最低相差35.58ug/g;锌含量变幅为12.29-33.47 ug/g,平均为21.11ug/g,最高与最低相差21.18ug/g;钙含量变幅为167.53-348.80ug/g,平均为248.59ug/g,最高与最低相差192.59ug/g;铜含量变幅为2.32-5.83 ug/g,平均为2.98ug/g,最高与最低的相差3.61ug/g;钾含量变幅为1822.71-4414.91 ug/g,平均为2617.87ug/g,最高与最低的相差2634.72ug/g;钠含量变幅为10.25-39.82 ug/g,平均为23.05ug/g,最高与最低的相差29.57ug/g。 两年不同小麦品种(系)中矿质元素的含量分析结果表明:铁、铜、钙、钠和钾含量年际变化不明显,说明小麦对铁、铜、钙、钠和钾的吸收较稳定;锌含量变化较大,可能受环境的影响比较大。分析各矿质元素含量与粗蛋白、湿面筋、沉降值及元素之间的相关关系,结果表明,锌含量与粗蛋白含量呈极显著正相关关系,相关系数为0.317,与湿面筋含量之间呈显著正相关,相关系数达到0.246;铁含量与粗蛋白含量呈显著的正相关关系,相关系数是0.262;铜、钙、钠和钾含量与粗蛋白含量、湿面筋和沉降值之间存在正相关,但不显著,其中钠与沉降值之间为负相关。表明施锌或铁对提高小麦粗蛋白和湿面筋有显著效应,其余矿质元素有促进作用但不明显。 利用RAPD分子标记技术对川育23、41058、川育20及其父母本进行分析,力图从分子水平找到小麦矿质元素含量之间的差异性,琼脂糖电泳结果表明不同的小麦品种(系)间扩增出了差异条带。 以上研究结果,将对筛选“微量营养强化型”小麦新材料,选育“微量营养强化型”小麦新品种奠定基础。 62 different wheat cultivars was digested with HNO3 in a tightly closed vessel heated under micro-wave,then contents of zinc,iron,copper,calcium,sodium and potassium were determined by inductively coupled plasma-atomic emission spectroscopy(ICP-AES).The main indexes of wheat quality such as total protein、wet glu and sedimentation volume were detected by Infratec 1255 Food & Feed Analyzer at the same time.The obtained results showed that variation for all of the mineral elements concentrations among different cultivars were observed .In 2006, the amplitude variation of the iron content was 18.55-58.19 ug/g,the average value was 30.83ug/g,and 39.64ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 5.70-25.8 ug/g,the average value was 15.13ug/g,and 20.10ug/g between the highest-content cultivar and the lowest one.In 2008, the amplitude variation of the iron content was 16.68-52.25 ug/g,the average value was 30.10ug/g,and 35.58ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 12.29-33.47 ug/g,the average value was 21.11ug/g,and 21.18ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the calcium content was 167.53-348.80ug/g,the average value was 248.59ug/g,and 192.59ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the copper content was 2.32-5.83 ug/g,the average value was 2.98ug/g,and 3.61ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the potassium content was 1822.71-4414.91 ug/g,the average value was 2617.87ug/g,and 2634.72ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the sodium content was 10.25-39.82 ug/g,the average value was 23.05ug/g,and 29.57ug/g between the highest-content cultivar and the lowest one. Analysis was made on the annual variation of mineral elements content in different Wheat cultivars ,the result shows:there is no obvious difference of iron ,copper ,sodium、calcium and potassium concentrations in wheat cultivars, suggesting the absorption of the iron, copper, sodium、calcium and potassium by wheat are relatively steady ,but zinc concentrations change obviously ,maybe influenced heavily by environment . The correlation between mineral elements 、mineral elements and total protein、mineral elements and sedimentation volume as well as mineral elements and wet glut were analysed in this paper, the result showed that there was significant positive correlation between zinc content and total protein (the correlation coefficient is 0.317), positive correlation between zinc content and wet glu (the correlation coefficient is 0.246), positive correlation between iron content and total protein (the correlation coefficient is 0.262). there was positive but not obvious correlation between the contents of copper, calcium, sodium or potassium and total protein, wet glut or sedimentation volume,among which was negative correlation between sodium and sedimentation volume.It was indicated zinc or iron fertilization has prominent effects in improving the total protein in wheat, the rest mineral elements have Non- obvious facilitation. The study then forecasted the genetic difference of different wheat by the molecular marker of RAPD in order to find differences in molecular level. Chuanyu23、41058、chuanyu20 as well as their male and female parents were analysed by RAPD markers,Agarose gel electrophoresis of DNA revealed the appearance of differential bands . The above-mentioned results of this study establish the foundation to screening the new materials of wheat of " strengthening type of micro- nutrition ", and to breeding the new wheat cultivars of" strengthening type of micro- nutrition ".

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本文筛选出一株能利用木糖产乙醇的丝状真菌Z7,对其利用木糖和半纤维素水解产物产乙醇的发酵条件进行了研究,并对Z7 利用玉米芯产木聚糖酶的条件进行了优化。全文分为三部分: 第一部分:目标微生物筛选、纯化及系统发育分析。以木糖为唯一碳源,采用梯度稀释和平板化线法从高温、中温酒曲中分离到16 株能利用木糖良好生长的丝状真菌;通过发酵试验复筛,获得一株能产乙醇的丝状真菌Z7;综合形态学和ITS 序列分析,初步鉴定为Aspergillus flavus。 第二部分:Z7 的乙醇发酵条件研究。以木糖为碳源,通过单因素试验确定最佳氮源和发酵温度;通过正交试验及SPSS 软件分析得到了不同N、P、K 成分对乙醇、残糖和菌体干重的影响。获得最佳的发酵条件为:(g/L)木糖50,尿素1, NH4NO3 1, K2HPO4 2 , KCl 0.5 , MgSO4.7H2O 0.5 , NaNO3 1 , pH 自然,培养温度33 ℃。以玉米芯半纤维素稀酸水解液为底物进行乙醇发酵,根据稀酸水解的单糖释放量和乙醇产量,确定115 ℃,1 h 为最佳玉米芯预处理条件;结合最佳发酵条件,添加1 g/L 的吐温20 能获得最大的乙醇浓度8.31 g/L。因此,Aspergillus flavus Z7 能利用半纤维素水解产物产乙醇,其中木糖的利用率80%以上。 第三部分:Z7 利用玉米芯产木聚糖酶条件优化。Aspergillus flavus Z7 在具有产乙醇能力的同时还具有产木聚糖酶的能力。本文通过单因素和正交试验得到最佳产酶培养基组分为:(g/L)玉米芯20,尿素2, 酵母膏2.5, K2HPO4 5,NaNO31, MgSO4.7H2O 1。单因素试验表明,用纱布代替塑料布密封摇瓶封口能显著提高产酶量;Z7 在碱性条件下具有更强的产酶性能。在最优条件下发酵,能产生最大木聚糖酶活122.23IU/mL。通过薄层分析,验证了Z7 产生的木聚糖酶具有水解木聚糖生成木糖及木寡糖的能力。 A strain of filamentous fungus which can produce ethanol by using the xylose was isolated in this research. The ethanol fermention conditions from xylose and dilute-acid hydrolyzate of the corn core were studied. The conditions of xylanase production by Z7 were also optimized. The paper involved three parts. Part1: Isolation, purification and phylogenetic analysis of the microbe. By using xylose as the single carbon source and the pla te streaking method, several filamentous fungi were isolated from the wine starter; through the fermentation test, a filamentous fungus Z7 which can produce ethanol was further recognized; furthermore, according to the morphologic observation and ITS seque nces analysis, Z7 was identified as Aspergillus flavus at the first step. Part2: Research on the condition of ethanol fermentation by Z7. By single factor experiment, the optional nitrogen resource and temperature of the fermentation were fixed; meanwhile, through the orthogonal array tests and the analysis of statistic software SPSS, the optional component of the culture medium and the fermentation condition were organized as follows: (g/L) xylose 50, urea 1, NH4NO3 1, K2HPO4 2, KCl 0.5 , MgSO4.7H2O 0.5, NaNO31, pH nature, temperature 33℃. Based on these optimal parameters, the fermentation of dilute-acid hydrolyzate of the corn core was carried on by Z7. According to the quantities of released sugar monomers and content of the ethanol, 115℃ in 1h is the best pretreatment condition; the maximal ethanol content can be obtained when 1g/L Tween 20 was added to. Therefore, the filamentous fungus Aspergillus flavus can use the hydrolysate of hemicellulose to produce ethanol, and the rate of xylose utilization was over 80%. Part3: Optimization of Z7’s xylanase producing condition from corn core. Aspergillus flavus Z7, which can utilize xylose or the hydrolysate of hemicellulose to produce ethanol, also had the ability of xylanase production. The optional component of the culture medium were fixed by the single factor experiment and the orthogonal array tests, and they were organized as follows: (g/L) corn core 20, Urea 2, Yeast extract 2.5, K2HPO4 5, NaNO31, MgSO4.7H2O 1; it was testified by the single factor experiment that sealing the shaking flasks with pledget other than plastic paper can obviously increase the xylanase activity; moreover, Z7 showed better xylanase production ability when in the alkali environment. Under the optional fermentation condition, the maximal xylanase activity 122.23IU/mL was proved. Through the analysis of thin- layer chromatography (TLC), the ability of xylanase from Z7, which can hydrolyze xylan to xylose monomer and oligomer, was vividly displayed.

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在引发剂过氧化二异丙苯(DCP)的作用下,通过添加少量界面增容剂苯乙烯(St)提高接枝率,使甲基丙烯酸缩水甘油酯(GMA)与(乙烯/丙烯/二烯)共聚物(EPDM)反应,得到接枝物EPDM-g-GMA,将EPDM-g-GMA与PET共混,以提高共混体系的冲击强度。探讨了不同含量的EPDM-g-GMA对共混体系力学性能的影响。结果表明,随着EPDM-g-GMA含量的增加,共混体系的缺口冲击强度显著提高,当其含量为50%时,材料的缺口冲击强度为344.9J/m,约为纯PET的12倍;拉伸强度、弯曲强度和弯曲弹性模量出现一定程度的下降;EPDM-g-GMA含量为20%~30%时,材料的综合力学性能较好。

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本文用循环伏安法研究了麦迪霉素推动质子从水相向硝基苯相或1,2-二氯乙烷相转移的过程,测定了麦迪霉素与质子在油相结合的稳定常数,建立了一种新的测定麦迪霉素的电化学方法。检测下限为10μg/mL,线性范围为20~1400μg/mL,样品检测结果与生物效价法相同。

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本工作利用一种改进型旋流雾室雾化氢化物发生装置,建立同时测定铅、砷、锑、铋、锗、锡及非氢化物元素的ICP-AES法。溶液中的Pb(Ⅱ)首先以H_2O_2-(NH_4)_2S_2O_8溶液氧化为Pb(Ⅳ),然后再与NaBH_4溶液反应产生氢化物,与由气动雾化产生的样品气溶胶一起被导入等离子体中。Pb,As,Sb,Bi,Sn,Ge的检出限分别为1.4,7.6,2.8,1.3,2.4和15μg/L,较通常的气动雾化法低20-60倍,硒、碲在氧化剂存在下不能产生氢化物。研究了共存元素的干扰及消除方法。实际样品(沉积物)分析结果与推荐值吻合。

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本文介绍了催化动力学分析的基本原理和常用方法,并以此对钒催化氯酸钾氧化盐酸氯丙嗪的反应进行研究,用正交试验方法对影响反应速度的温度、酸度、反应物浓度及反应时间诸因素进行研究,确定了最佳反应条件,建立了新的催化光度测定痕量钒的新方法。该方法灵敏度高一极限灵敏度为3 * 10~(-10)g/ml;选择性好-常见20多种离子不干扰测定;重现性好-对0.12μg标准钒进行12次测定,统计结果相对标准偏差为3. 35%,是催化动力学法用于痕量钒测定的理想方法。本研究工作以新建的CPH-KCO_3体系,对海洋生物(如海藻和双壳动物),天然水(流水及湖水)及粮食(大米、面粉)中的痕量钒进行了测定,从回收实验结果看,测定方法可行结果可靠。本文初步探讨了钒催化氯钾氧化CPH的反应机理,提出了两步氧化的反应历程。指出氧化剂的氧化性强弱直接影响催化光度分析的灵敏度。并对校正曲线偏离原点的原因加以讨论。另外,文中对正交试验结果进行数学计算,进一步表明正交试验是实现分析测试条件优化的最佳途径。