共查询到20条相似文献,搜索用时 62 毫秒
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血迹检验是最常见也是最重要的一种法医物证检验,其预备实验和确证实验涉及化学科学中的许多理论和技术。具体来说,预备实验基于血红蛋白的催化性质,包括酚酞、联苯胺及其衍生物、隐色孔雀石绿、荧光素、鲁米诺等物质的显色或发光反应;确证实验基于血红蛋白中血红素的配位性质,包括血红素生成氯化血红素和吡啶血色原的结晶反应。通过系统梳理和归纳,丰富充实了分析化学的教育教学内容。 相似文献
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学生在解决酸碱滴定曲线情境问题时常常存在各种思维障碍,基于模型建构及其应用,有助于解决学生酸碱滴定曲线解题思维障碍。剖析例题内在结构要素,聚焦电解质溶液滴定曲线命题关注的5个点,即起始点、等料点、等量点、中性点、恰好点。从“五点”出发,进行解题思维模型的建构,指引学生解题思维的发散与收敛等。精选试题情境为载体,将建构的模型思维应用于酸碱滴定曲线相关问题的解决,助力于真实情境中思维的启发、精准切入与生成等。实践过程中提升学生的模型认知核心素养,提升学生的化学学科思维品质。 相似文献
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基于Monte Carlo模拟的化学反应动力学参数估算 总被引:2,自引:0,他引:2
提出并采用基于MonteCarlo模拟与动力学实验相结合的化学反应动力学参数估算方法,由基元反应确定MonteCarlo模拟具体做法,将MonteCarlo模拟结果与动力学实验结果相比较,根据比较结果自动调整和优化动力学参数,从而无需事先确定动力学方程即可有效估算各种化学反应的动力学参数值.采用该方法估算了丙烯氨氧化反应动力学参数,并对估算结果进行了分析与讨论. 相似文献
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Suset Rodríguez-Alemn Ernesto M. Hernndez-Cooper Rolando Prez-lvarez Jos A. Otero 《Molecules (Basel, Switzerland)》2021,26(2)
Front tracking and enthalpy methods used to study phase change processes are based on a local thermal energy balance at the liquid–solid interface where mass accommodation methods are also used to account for the density change during the phase transition. Recently, it has been shown that a local thermal balance at the interface does not reproduce the thermodynamic equilibrium in adiabatic systems. Total thermal balance through the entire liquid–solid system can predict the correct thermodynamic equilibrium values of melted (solidified) mass, system size, and interface position. In this work, total thermal balance is applied to systems with isothermal–adiabatic boundary conditions to estimate the sensible and latent heat stored (released) by and salts which are used as high-temperature phase change materials. Relative percent differences between the solutions obtained with a local thermal balance at the interface and a total thermal balance for the thermal energy absorbed or released by high-temperature phase change materials are obtained. According to the total thermal balance proposed, a correction to the liquid–solid interface dynamics is introduced, which accounts for an extra amount of energy absorbed or released during the phase transition. It is shown that melting or solidification rates are modified by using a total thermal balance through the entire system. Finally, the numerical and semi-analytical methods illustrate that volume changes and the fraction of melted (solidified) solid (liquid) estimated through a local thermal balance at the interface are not invariant in adiabatic systems. The invariance of numerical and semi-analytical solutions in adiabatic systems is significantly improved through the proposed model. 相似文献
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Dr. Paula F. De Castro Dr. Adham Ahmed Prof. Dmitry G. Shchukin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(13):4389-4394
We have encapsulated the heat exchange material, n‐docosane, into polyurethane capsules of different sizes. Decreasing the size of the capsules leads to changes of the crystallinity of phase‐change material as well as melting/crystallization temperature. The novelty of the paper includes 1) protection of the nanostructured energy‐enriched materials against environment during storage and controlled release of the encapsulated energy on demand and 2) study of the structure and surface‐to‐volume properties of the energy‐enriched materials dispersed in capsules of different sizes. The stability of energy nanomaterials, influence of capsule diameter on their energy capacity, homogeneity and operation lifetime are investigated. 相似文献
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E. Malhotra N. K. Kaushik G. S. Sodhi 《Journal of Thermal Analysis and Calorimetry》2001,65(3):859-864
Ionic chelate complexes of kojic acid(I) and hafnium(IV) of the type [(η5-C5H5)2HfL]+[MCl3]– (II)[HL=kojic acid; M=Zn(II), Cd(II), Hg(II), Cu(II)] have been synthesised and characterised by spectral studies (IR, UV, 1H NMR and 13CNMR). Thermogravimetric (TG) and differential thermal analytical (DTA) studies have been carried out for these complexes
and from the TG curves, the order and apparent activation energy for the thermal decomposition reactions have been elucidated.
The various thermal studies have been correlated with some structural aspects of the complexes concerned. From DTA curves,
the heat of reaction has been calculated.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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为提高高等教育教学质量,促进教学效果提升,加强高分子化学实验教学内容建设。结合学院专业设置及人才培养方案,在协同创新思想的指导下,增进高分子化学实验与食品工程、药剂学、环境工程的有效协同,多学科融合,创建了一系列跨学科的综合性实验项目,体现了协同创新育人的教学理念,拓展了学生视野,培养了学生的创新精神和实践能力。出版了基于校校合作的实验教材,建成了省级精品课程网站,保持教材建设和精品课程建设的可持续性发展,增强实验内容的先进性、全面性、导向性。 相似文献
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催化激光热透镜光谱法测定铜 总被引:5,自引:0,他引:5
基于铜催化邻苯二胺氧化反应,以激光热透镜光谱法测定微量铜,讨论了测定条件的影响。结果表明,该方法测定灵敏度高,在0.2-1.2μg/L铜(Ⅱ)浓度范围内呈线性关系,重现性及回收率实验均取得满意的结果。 相似文献
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Thermal studies on some organotin(IV) complexes with piperidine and 2-aminopyridine dithiocarbamates
The complexes of piperidine dithiocarbamate, 2-aminopyridine dithiocarbamate and organotin(IV) of the type R3Sn(L1), R2Sn(L1)2, R3Sn(L2), R2Sn(L2)2, [R=C6H5CH2 (benzyl), p-ClC6H4CH2 (p-chlorobenzyl), L
1=sodium piperidine dithiocarbamate and L
2=sodium 2-aminopyridine dithiocarbamate] have been synthesised and characterised by spectral studies (IR, UV, 1H NMR). Thermogravimetric (TG) and differential thermal analytical (DTA) studies have beeen carried out for these complexes and from the TG curves, the order and apparent activation energy for the thermal decomposition reactions have been elucidated. The various thermal studies have been correlated with some structural aspects of the complexes concerned. From DTA curves, the heat of reaction has been calculated. 相似文献