保定师专学生微量元素含量测定与分析

用火焰原子吸收光谱法对保定师专部分学生发样中微量元素Fe、Zn、Ca、Pb含量进行了测定．对师专学生微量元素含量情况进行了分析，并对其饮食习惯提出建议。     

279例儿童全血铅镉铜锌钙镁铁检结果分析

目的通过279例儿童全血铅镉铜锌钙镁铁含量分析,了解我市儿童微量元素状况,探讨影响因素。方法采用原子吸收光谱法。结果微量元素基本平衡;缺铁钙,年龄越小,截止多缺乏。     

原子吸收法测定人发中的微量元素

人发中含有多种微量元素,其含量与人的每日摄入量及其在体内的代谢情况有密切关系,可以利用它作为衡量人对微量元素接触、吸收、代谢程度以及其对机体危害程度的一种指标。因而自六十年代以来,发样中微量元素的分析,在临床营养、环境污染及实验室的研究中已相当普遍。人发中微量金属元素的测定方法有原子吸收法、皑化波极谱法,电感耦合高频法,等离子发射光谱法及荧光光度法等。我们于一九八六年用火焰原子吸收分光光度法测定人     

保定地区儿童头发中微量元素的含量测定

用火焰原子吸收光谱法测定儿童头发中的微量元素Fe、Zn、Ca、Pb的含量,并将城市和农村儿童头发中Fe、Zn、Ca、Pb的含量进行比较,探讨营养、环境污染等诸多因素对儿童身体、智力发育造成的影响。     

茶叶中微量元素的溶出规律

沸水浸泡茶叶,应用原子吸收光谱法测定了绿茶和红茶的茶叶干样、茶水和茶渣中8种微量元素含量,计算茶叶中微量元素的溶出率和残留率,探讨茶叶中微量元素的溶出规律。结果表明,绿茶和红茶的茶叶干样、茶水和茶渣中8种微量元素含量及溶出率、残留率各有差异。     

不同民族胆红素含量和早发冠心病对比研究

目的为了研究不同民族胆红素水平和早发冠心病的关系。方法将862例冠心病患者分为早发冠心病和一般冠心病,冠心病患者中男性年龄都<55岁,女性患者的年龄<65岁,将他们分为2组,其中早发冠心病419例为实验组(其中回族181例,汉族238例),另外的443例为对照组(其中回族234例,汉族209例)。我们将从冠状动脉Gensini总积分和病变支数来分析。结果在汉族病人中,对照组病人的间接胆红素和总胆红素含量要比实验组高;在回族病人中,对照组的的直接胆红素和总胆红素含量要比实验组高,我们用统计学方法统计出他们之间的差异。在实验组中,汉族病人直接胆红素和总胆红素高于回族。结论独立导致早发冠心病的因素可能是胆红素。     

略论铅及其他微量元素对儿童健康的影响

介绍了几种微量元素对儿童健康的影响,略论了话对儿童身体发育的危害.通过几个微量元素的例证说明了截量元素的适当撮入对儿童的身体健康是有百利而无一害通过准确的数据证明了血铅含量越高对儿童身体伤害越大以及这些伤害的不可逆转性列举了儿童铅中毒后的一些症状.     

呼和浩特市222例不同民族儿童头发中锌铁铜镁钙含量的比较研究

本文测定了呼市地区222名不同民族、不同性别8岁健康儿童头发中锌铁铜镁钙的含量。结果发现同年龄同性别不同民族儿童头发中上述五种元素含量有一定的区别。     

佝偻病患儿微量元素分析

目的探讨佝偻病患儿微量元素缺乏情况,为临床治疗提供依据。方法随机选择2009年1月至2010年1月在我所确诊的佝偻病患儿30例设为佝偻病组,并随机选择同期在我所体检的健康儿童30例设为健康组,检测2组儿童头发样本中的微量元素含量,以分析佝偻病儿童微量元素缺乏情况。结果佝偻病组儿童头发中铁、铜元素的含量与健康组比较差异有统计学意义(P>0.05),而钙和锌元素的含量明显低于健康组,差异有统计学意义(P<0.01)。结论佝偻病患儿铁和铜元素缺乏并不明显,但钙和锌缺乏明显,在治疗过程中,除了应常规补充钙元素外,还应根据情况,补充其他微量元素。     

火焰原子吸收法测定野生香菇中5种微量元素

为了比较浙江、湖北、河南及云南野生香菇对Fe、Cu、Mg、Ca、Ni 5种微量元素的富集能力,了解不同地区野生香菇的营养价值提供初步科学依据。采用火焰原子吸收法测定Fe、Cu、Mg、Ca、Ni 5种微量元素。结果表明,不同产地的野生香菇中Mg的含量接近,而Fe、Cu、Ca、Ni含量各不相同,其中Fe和Ca的含量相对较高,Cu、Ni和含量相对较低;云南大理野生鸡枞对这5种微量元素含量富集能力较强。云南大理野生香菇中各种微量元素含量均较高,可初步得出其营养价值较高。     

底座连接口特征参数对显示器后壳注塑质量的影响分析

在Moldflow分析软件的基础上,对显示器后壳进行仿真研究,以翘曲变形量为质量指标,结合控制变量法进行单因素变动实验,保持注射工艺参数不变,研究显示器后壳底座连接口对制品翘曲变形的影响.对数据进行图表分析,结果表明显示器后壳尺寸定位68.58 cm(27英寸)时,底座连接口选用圆形,连接口位置距离底边26 mm,尺寸...     

The role of the symmetry and the flexibility of the anion on the characteristics of the nanostructures and the viscosities of ionic liquids☆

The transport properties of ionic liquids (ILs) are crucial properties in view of their applications in electrochem-ical devices. One of the most important advantages of ILs is that their chemical–physical properties and conse-quently their bulk performances can be well tuned by optimizing the chemical structures of their ions. This will require elucidating the structural features of the ions that fundamentally determine the characteristics of the nanostructures and the viscosities of ILs. Here we showed for the first time that the“rigidity”, the order, and the compactness of the three-dimensional ionic networks generated by the anions and the cation head groups determine the formation and the sizes of the nanostructures in the apolar domains of ILs. We also found that the properties of ionic networks are governed by the conformational flexibility and the symmetry of the anion and/or the cation head group. The thermal stability of the nanostructures of ILs was shown to be con-trolled by the sensitivity of the conformational equilibrium of the anion to the change of temperature. We showed that the viscosity of ILs is strongly related to the symmetry and the flexibility of the constitute ions rather than to the size of the nanostructures of ILs. Therefore, the characteristics of the nanostructures and the viscosities of ILs, especially the thermal stability of the nanostructures, can be fine-tuned by tailoring the symmetry and the conformational flexibility of the anion.     

浅谈设备的性能与操作对胎面压出质量的影响

简要介绍了胎面压出的工作原理及工艺过程，对设备的配置及操作对胎面压出质量的影响进行了分析，并对压出过程中常见的质量缺陷、造成的原因以及解决措施提出了自己的见解。     

Investigation of the effects of fatty acids on the compressive strength of the concrete and the grindability of the cement

In cement industry, a great energy consumption has been observed during grinding of clinker. To reduce this consumption, some waste products have been used as grinding aids.In this investigation, the effects of sunflower oil (SO), oleic acid (OA), stearic acid (SA), myristic acid (MA) and lauric acid (LA) on the fineness and strength of the cement have been examined. These aids were added into clinker in certain ratios based on the cement clinker weight and the grinding has been done for a definite time at the same condition.All of the fatty acids used increased the fineness as compared with the cement without the grinding additives. SO and OA decreased the strength significantly, LA decreased it to a lesser extent and SA increased it definitely according to the common cement. But MA did not alter the strength of the cement as much as SA. In addition, the covering of the balls influences the grinding of cement clinker unfavourably.     

煤粉流动性对GSP气化炉气力输送的影响研究

针对GSP气化装置煤粉气力输送在试车阶段出现的煤粉锁斗下料不畅、发料罐输送性能不佳等问题,从原料煤性质和工业装置的改进方面出发,通过煤粉的流动性参数的测量与研究,分析出现上述工程问题可能的内在原因,并提出工业装置改进方法,为保证GSP煤粉气力输送工业装置的正常运行提供解决办法。     

关于建立火炸药安全数据库的探讨

由反映火炸药及其制品的危险性能和用于对它们的生产、储运系统进行安全评价数学模型出发,探讨了如何建立一个全面、实用的火炸药安全评估数据库。通过对此数据库内容、数据表示方法、数据搜索方法以及建立步骤的讨论,明确了该数据库的使用对象和主要功能。     

The effect of the length of the oxyethylene chain on the conductivity of the polyurethaneurea electrolyte

Polyurethaneureas (PUU), which were synthesized from 4,4′-diphenylmethane diisocyanate (MDI), poly(ethylene glycol) (PEG), and 3,5-diaminobanzoic acid (DABA), were used as polyelectrolytes in this study. Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR) were used to monitor the effect of the various kinds of PEG on the changes in morphology of PUU electrolytes corresponding to the concentration of lithium perchlorate (LiClO₄) dopants. The results of DSC and FT-IR indicate the Li⁺ ions coordinate with the soft and hard segments. Additionally, the crystallinity of the PEG soft segment and the ordered hydrogen-bonded urea carbonyl groups decreased with increasing salt concentration. Impedance spectroscopy (IS) measurements show that the PUU electrolyte with the high phase separation degree has the high ionic conductivity. The hard-segment T_g and the soft-segment T_m influence the conductivity behavior of polyelectrolytes with increasing measurement temperature.     

Effect of the drafting force on the strength of the bottom of the spinneret

In spinning basalt fibres, the drafting force is in the same range as in spinning of glass fibres. The effect of the drafting force can not be considered in the calculation for the strength and rigidity of the bottom of the spinneret. __________ Translated from Khimicheskie Volokna, No. 5, pp. 47–50, September–October, 2007.