P物质--甲醛急性刺激效应的分子生物标志物

分别用0 mg/m3、1 mg/m3、2 mg/m3、3 mg/m3的甲醛对10名受试者进行眼部控制暴露,暴露时间5 min,测定暴露前后鼻腔灌洗液中P物质含量. 结果表明,甲醛暴露后鼻腔灌洗液中P物质含量增加,尤其是3 mg/m3甲醛暴露组P物质含量增加尤为显著(p<0.05). 这说明甲醛刺激眼部三叉神经末梢后,会通过局部轴突反射,引起鼻腔内的三叉神经末梢释放P物质. 因此P物质可作为评价甲醛急性刺激效应的分子生物标志物.     

糖化阶段酚类氧化酶去除多酚物质的应用效果评价

研究了糖化阶段多酚氧化酶(PPO)、过氧化物酶(POD)、PVPP和甲醛对麦汁酚类物质含量及抗氧化能力的影响,比较了PPO、POD、PVPP和甲醛在糖化阶段改善啤酒稳定性的应用效果.结果表明,添加PPO可使麦汁酚类物质含量和抗氧化力降低,色度和浊度上升,麦汁的粗糙口感形成;而POD的添加并没有对麦汁的外观品质产生负面影响,反而对降低酚类物质含量和TBZ值、提高抗氧化力有益.由此说明酚类氧化酶在改善啤酒的稳定性方面具有潜在的应用价值.     

涂料和装饰材料中甲醛的定性检测

甲醛(HCHO)是一种无色、具有刺激性且易溶于水的气体.它有凝固蛋白质的作用,其35%～40%的水溶液被称为福尔马林,常作为浸渍标本的溶液.甲醛为具有较高毒性的物质,在我国有毒化学品优先控制名单上居第二位.     

高效液相色谱测定化妆品中甲醛方法的探索

化妆品中常添入甲醛以达到杀菌防腐的目的,但国家规定有一定的限量.《化妆品卫生规范》中常应用乙酰丙酮分光光度法测定化妆品中甲醛,文献中也有用变色酸分光光度法测定化妆品中甲醛,缺陷是该方法易受酚和其他醛类物质的干扰.本文在参考国外文献的基础上,利用高效液相色谱技术对化妆品甲醛含量的测定进行了探索,获得了比较满意的结果.     

甲醛对果蝇的伤害及维生素C的保护作用研究

以果蝇为材料,探讨了甲醛对果蝇的伤害作用以及维生素C的保护作用.分析了在甲醛和维生素C的影响下,果蝇子代的生存率、幼虫体内的几种主要物质(如核酸和蛋白质)含量的变化动态以及细胞内产生的微核数等.结果发现,随着培养基中甲醛浓度的升高,果蝇子代数量逐渐减少;幼虫体内的蛋白质含量有所降低,核酸含量变化不明显,细胞内微核数量增高.而维生素C对甲醛的毒害存在显著的拮抗效应.当培养多代后,这些效应逐渐减轻.     

甲醛克星——光触媒窗帘

室内污染的最主要物质就是——甲醛。甲醛是胶黏剂的重要组成部分,所以凡是涉及到胶黏剂的,包括人造板、涂料、地毯、家具都会含有甲醛,甲醛超标成为一个广受关注的问题。来自中国室内装饰协会的调查结果显示,目前我国城镇居民家庭中80%存在甲醛超标问题。甲醛是世界卫生组织公认的一类致癌物,长期接触低剂量甲醛可引起慢性呼吸道疾病,女性月经紊乱,妊娠综合症,染     

室内污染物质甲醛分析方法的改进

甲醛是当今室内污染的主要物质,分析甲醛的主要方法有乙酰丙酮分光光度法和酚试剂法,乙酰丙酮分光光度法分析甲醛显色过程又有常温和沸水浴两种方法,为此本文对乙酰丙酮分光光度法分析甲醛过程中采用何种方式能更准确、更高效等问题进行讨论。     

磁微球在测定水中痕量甲醛中的应用

应用磁微球与甲醛反应生成电活性物质,在磁性电极上聚集并还原以检测甲醛,以磁微球的制备、电极的结构及影响这些测定的各种因素进行了研究,在最佳条件下,甲醛峰电位为-1.04V(vs,SCE),检测下线为0.2μg/L,利用此方法测定了环境水样中的甲醛。结果满意。     

装修引发甲醛污染的探讨

随着社会经济的发展和人民生活水平的提高,房屋的装修污染问题日益严重。装修所使用的不合格材料如板材、涂料、油漆等中含有甲醛等污染物质,从而引起室内空气污染,严重影响居民的身体健康。本论文所分析研究的是房屋在不同装修材料和不同装修时间下,室内污染物质甲醛的含量情况。先通过对6户刚装修完成1～6个月的居民住宅的书房、厨房、客厅、主卧室及次卧室等采样点进行采样,再采用酚试剂分光光度法对采集的甲醛样品的含量进行检测,最后分析得出了室内甲醛含量与装修材料、装修时间的关系。     

空气中甲醛快速检测法的探究

甲醛是空气中的首要污染物,在我国有毒化学品优先控制名单上甲醛高居第二位。室内空气中的甲醛主要来源于建筑装饰材料、家具、各种粘合剂、涂料、合成纺织品等。甲醛的主要危害表现在能与人体的蛋白质结合,破坏蛋白质。甲醛对人体健康的影响主要表现在嗅觉异常、刺激、过敏、肺功能异常、肝功能异常等方面。可引起鼻咽癌、结肠肿瘤、细胞核基因突变、抑制D N A损伤修复、月经紊乱、妊娠综合症、新生儿染色体异常,甚至可以引起白血病。甲醛已经被世界卫生组织确定为致癌和致畸形物质,是公认的变态反应源,也是潜在的强致突变物之一。因此甲醛的监测越来越受到人们的重视。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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