Results 91 to 100 of about 4,430 (197)
Malandro é malandro, mané é mané
Este trabalho analisa características de uma personagem imortalizada em nossa música popular por Moreira da Silva, o Kid Morengueira: o malandro, que, para DaMatta (1994) se revela, no contexto da sociedade brasileira, "um profissional do jeitinho". O malandro prototípico materializa o que Antonio Candido (2004) denomina de "a dialética da malandragem"
openaire +2 more sources
探究枫香(Liquidambar formosana Hance)对铅污染土壤的修复作用,为缓解土壤铅危害和枫香在重金属污染地推广种植提供科学参考,以1年生枫香幼苗为试材,设置6个Pb2+浓度(分别为0,100,300,500,800,1 000 mg/kg)对各Pb2+浓度环境下枫香幼苗的生理特性和积累特性进行研究,并采用主成分分析法对枫香的12个生理指标进行筛选以及耐性评价。结果表明,随着Pb2+的增加,枫香幼苗叶片的生物量、可溶性糖含量、可溶性蛋白含量、游离脯氨酸含量、超氧化物歧化酶(SOD ...
蒋严波 +5 more
doaj
Improvement of Electrochemical Performance of Manganese-based Lithium-Rich Cathode Materials for Lithium-ion Battery [PDF]
近年来,锂离子电池富锂锰基正极材料xLi2MnO3•(1-x)LiMO2(M=Mn,Co,Cr,Ni等)由于具有较高的比容量(≥250mAh/g)、热稳定性好、成本低廉以及对环境友好等优点,引起了研究者的广泛关注和研究。本论文选择Li1.14Ni0.18Mn0.62O2富锂锰基正极材料作为研究对象,采用一种简单的熔融盐法,以改善电化学性能为目标,对于熔融盐的选择、煅烧温度及时间的控制、熔融盐用量等条件进行研究,调控了材料的结构并提高了电化学性能;然后通过使用新型粘结剂,抑制了该材料的电压衰减,
张涛
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[Normative values of cervical sagittal alignment according to the whole spine balance: Based on 126 asymptomatic Chinese young adults]. [PDF]
Tang YC, Zhao WK, Yu M, Liu XG.
europepmc +1 more source
Preliminary study of 210Bi/210Pb disequilibrium in coastal sediments [PDF]
210Bi属于铀系衰变链核素,半衰期5.01d,母体为210Pb,子体为210Po。在海洋学中,对其母体210Pb和子体210Po已有较多的研究,对210Bi的相关研究却鲜有涉足。 Kim等(2014)认为,210Bi有很强的颗粒活性,对210Po/210Pb不平衡有重大的贡献。学者们在利用210Po/210Pb不平衡测POC输出通量时,均没有考虑210Bi的影响,可能高估了POC通量。因此,有必要研究210Bi的生物地球化学行为特征。 Biggin等(2002 ...
刘凌峰
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O humano é viável? É educável?
O texto parte de uma constatação histórica; a pedagogia nasce colada a uma crença: o humano é viável. Todo ser humano é educável. Essa crença não está em crise? Na primeira parte deste texto, apontam-se as manifestações atuais dessa descrença na viabilidade do humano e na educabilidade de jovens, adolescentes e crianças submetidos à nova segregação ...
openaire +3 more sources
采用盆栽试验研究了酸性黄壤铅污染下4种草本植物根际土壤微生物数量和酶活性的变化。结果表明:植物根际土壤中细菌、真菌和放线菌对铅污染的响应因植物根系环境的不同而有所区别:4种植物根际土壤中细菌和真菌数量增加,但增幅不一致。黑麦草和早熟禾根际土壤放线菌数量降低,翦股颖根际土壤放线菌数量呈现波动起伏。4种植物根际土壤中过氧化氢酶活性、淀粉酶活性和中性磷酸酶活性与土壤铅含量都表现出负相关性,与淀粉酶活性负相关达到极显著,铅对黑麦草和狗牙根根际土壤脲酶活性表现出低浓度下激活高浓度下抑制 ...
石汝杰, 陆引罡
doaj
Applications of Aqueous Metal Phthalocyanine Spectroscopic Probes in the Analysis of Biomacromolecules and Inorganic Anions [PDF]
金属酞菁是一类化学性质稳定(耐热、耐酸、耐碱),较易合成的化合物。自Braun和Tehemiac获得第一个酞菁化合物以来,酞菁化合物由于其特殊的物理化学和光学性质而在化学和化工领域得到了广泛研究和应用。上世纪80年代开始,酞菁化合物在生物医学领域的应用也逐步得到开发应用。由于金属酞菁的吸收峰和荧光发射峰都在长波区段,可以避开绝大多数天然物质背景光的干扰,在生物化学分析中具有广泛的应用前景。本论文围绕水溶性金属酞菁作为分子探针在生物大分子和无机阴离子检测中的应用而展开 ...
杨惠卿
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本研究采用石墨炉原子吸收光谱法,测定了牡丹江工业区和绿化区内[树]麻雀、白鹊鸰、大苇莺、红尾伯劳4种雀形目鸟类夏季心脏、胸肌、肝脏、初级飞羽4种组织内铅和镉2种金属元素的残留量。研究表明,4种雀形目鸟中,铅和镉的残留量最高的组织均为初级飞羽,且不同物种间存在种间差异。工业区和绿化区之间4种鸟体内铅和镉的残留量大多存在显著 ...
宫茜茜 +4 more
doaj
Constraints on timing of the early-paleoproterozoic magmatism and crustal evolution of the Oulongbuluke microcontinent: U-Pb and Lu-Hf isotope systematics of zircons from Mohe granitic pluton [PDF]
The Olongbuluke micro-continent is composed of a two-fold basement with cover strata. The lower basement is the medium-to high-grade Delingha complex (DC) and the Dakendaban Group, the upper is the low-grade Wandonggou Group.
Chen, N +6 more
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