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纵观陶瓷发展历程,数字与品种命名相结合,使品种方便记忆辨识,也颇显韵味。陶瓷中由于历史发展、社会变迁,陶瓷产品种类出现众多变化,而陶瓷产品变化中又有其独特的特点,从原料生产、制作工艺、制作题材、规格大小、风俗文化内容;从产品功用到产品造型等均出现了以数字表现并命名的陶瓷器产品。 相似文献
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纯碱产品出现“色碱”是联碱生产中常见的现象,而“色碱”产生的原因是产品中出现了铁杂质,本文结合生产实际情况,从化学反应机理角度分析纯碱产品含铁现象的根源,并针对传统的碳化塔“挂硫”操作对碳化反应的利、弊进行了分析,对“挂硫”的可行性进行了全面论证,最终提出了可行性解决建议。 相似文献
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在粘胶长丝的生产中,成品丝时常出现低强、低伸现象,使产品降等。为此,我们对粘胶长丝出现低强、低伸的原因做了大量细致地调查,测试了诸多相关数据,进行模拟试验,基本找到了造成丝条强度和伸度低的原因,并积极采取措施,使强度和伸度降等得到有效控制。 相似文献
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渭化集团公司的尿素装置投产已6年整了。总结对比了开车以来的尿素产品的产量、消耗、产品质量、停车次数等各项指标,列举了工艺、设备、电仪等方面出现的问题。通过消化、吸收尿素装置的技术,进行了多项技改技革,收到了明显的效果。提出了今后进一步搞好生产,降低成本,生产优秀产品的奋斗目标。 相似文献
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环氧大豆油生产中一些技术问题的探讨 总被引:3,自引:0,他引:3
本文针对生产中出现的产品酸值高、色泽深、环氧值低、热稳定性差等技术问题,从整个生产过程着手,分析了每一环节出现的问题,并提出了可行的解决办法. 相似文献
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催化装置粗汽油回炼技术在有效降低催化稳定汽油烯烃含量的同时,对催化装置产品分布产生明显的影响,继而影响到装置的综合经济效益。本文对不同粗汽油回炼量条件下,催化装置稳定汽油性质和产品分布变化趋势进行分析,对经济效益进行对比,阐明应用粗汽油回炼降低汽油烯烃技术时,要选择合适的操作条件,以期得到较好的综合经济效益。 相似文献
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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. 相似文献
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On the basis of previous experimental results in a torus reactor, micromixing time is determined using the incorporation model. Obtained results allowed the characterisation of the performances of this new configuration of reactor in comparison to other reactors, such as the stirred tank reactor. In addition, a correlation is proposed for each incorporation law, in order to determine the micromixing time from the experimental micromixedness ratio (α). Finally, in terms of Kolmogorov's turbulence theory, a relationship between micromixing time and the local energy dissipation rate is obtained and compared to those previously published. 相似文献
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Dr. Prashasti Kumar Prof. Pratul K. Agarwal Dr. Matthew J. Cuneo 《Chembiochem : a European journal of chemical biology》2021,22(2):288-297
Few other elements play a more central role in biology than hydrogen. The interactions, bonding and movement of hydrogen atoms are central to biological catalysis, structure and function. Yet owing to the elusive nature of a single hydrogen atom few experimental and computational techniques can precisely determine its location. This is exemplified in short hydrogen bonds (SHBs) where the location of the hydrogen atom is indicative of the underlying strength of the bonds, which can vary from 1–5 kcal/mol in canonical hydrogen bonds, to an almost covalent nature in single-well hydrogen bonds. Owing to the often-times inferred position of hydrogen, the role of SHBs in biology has remained highly contested and debated. This has also led to discrepancies in computational, biochemical and structural studies of proteins thought to use SHBs in performing chemistry and stabilizing interactions. Herein, we discuss in detail two distinct examples, namely the conserved catalytic triad and the photoreceptor, photoactive yellow protein, where studies of these SHB-containing systems have permitted contextualization of the role these unique hydrogen bonds play in biology. 相似文献
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The analysis of the concrete subjected to high temperatures is usually undertaken by means of tests specifically designed and carried out in the laboratory, or by using theoretical approaches using standardized curves for theoretical fires. An analysis by different techniques has been carried out on structural concrete to real fire of Windsor Building in Madrid, which was severally damaged by a fire in 2005. These techniques are X‐ray diffraction, differential thermal and thermogravimetric analysis and backscattered electron microscopy with dispersive X‐ray microanalysis. Samples of the concrete were taken from different floors in the building and analyses were carried out at different depths starting from the surface exposed to the fire itself. The analysis allows the damaged area to be limited as well as situating the 500°C isotherm in the concrete element. In accordance with the results obtained, the damage is limited to just a few centimeters from the surface exposed to the fire itself, in spite of its prolonged exposure to the fire. This would justify that the concrete has demonstrated a suitable resistant behaviour. Likewise, it can be deduced from the results obtained that the fire, to which the concrete was subjected, can be qualified as severe. Also, these results can confirm that the calculation hypothesis in the project is correct in relation to the fire resistance exigencies of the concrete. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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目前,全日制专业学位研究生在校生已具有相当规模,他们的思想状况究竟有哪些特质,给我们的思政工作带来了哪些新挑战,突破点在哪里?这些都是我们亟待解决的问题。本文旨在结合作者的工作体会,对以上问题进行探究。 相似文献
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土壤特性及铅迁移转化规律的研究 总被引:2,自引:0,他引:2
通过对土壤的理化性质pH值、有机质、腐殖质的测定,寻找出土壤的理化性质对铅的含量与分布的影响规律,并进一步摸索出土壤中不同形态铅的浸提剂,测定各形态铅的含量,总结出了铅在土壤中的迁移转化规律,为铅污染的防治提供了理论依据。 相似文献