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101.
102.
通过制备印刷层、遮盖层、发泡层、增强层母料,再将上述各挤入层的熔融胶状物通过同一模头挤出发泡,经常规三辊压光、冷却、牵引、收卷,即得到七层熔融共挤出石头纸。采用该方法制备的石头纸,挺度好、印刷适应性好,比重低,不透明度高、平滑度好、厚度均匀,各项性能指标符合GB/T22806-2008"白卡纸"的性能指标要求,可用于印制美术印刷品、卡片、名片、包装纸盒等。该制备方法在云南昆钢石头纸环保材料有限得到工业化实践。 相似文献
103.
104.
Darikha Kudasova Botagoz Mutaliyeva Kristina Vlahovi
ek-Kahlina Slaven Juri Marijan Marijan Svetlana V. Khalus Alexander V. Prosyanik Suzana egota Nikola pani Marko Vincekovi 《International journal of molecular sciences》2021,22(5)
A new copper complex, trans-diaqua-trans-bis [1-hydroxy-1,2-di (methoxycarbonyl) ethenato] copper (abbreviation Cu(II) complex), was synthesized and its plant growth regulation properties were investigated. The results show a sharp dependence of growth regulation activity of the Cu(II) complex on the type of culture and its concentration. New plant growth regulator accelerated the development of the corn root system (the increase in both length and weight) but showed a smaller effect on the development of the wheat and barley root systems. Stimulation of corn growth decreased with increasing Cu(II) complex concentration from 0.0001% to 0.01% (inhibition at high concentrations—0.01%). The development of corn stems was also accelerated but to a lesser extent. Chitosan-coated calcium alginate microcapsules suitable for delivery of Cu(II) complex to plants were prepared and characterized. Analysis of the FTIR spectrum showed that complex molecular interactions between functional groups of microcapsule constituents include mainly electrostatic interactions and hydrogen bonds. Microcapsules surface exhibits a soft granular surface structure with substructures consisting of abundant smaller particles with reduced surface roughness. Release profile analysis showed Fickian diffusion is the rate-controlling mechanism of Cu(II) complex releasing. The obtained results give new insights into the complexity of the interaction between the Cu(II) complex and microcapsule formulation constituents, which can be of great help in accelerating product development for the application in agriculture 相似文献
105.
《International Journal of Hydrogen Energy》2022,47(74):31911-31926
Because of the requirement of the utilization of energy resources in a way that is both effective and efficient, solid oxide fuel cells have become a notable preference due to their advantages such as high efficiency and use with different fuels. In addition, the integration of these systems in the production of alternative fuels such as hydrogen and ammonia are important for a sustainable future to combat environmental problems. For this reason, the main intention of this paper is to introduce a new plant combining the different systems that use the solid oxide fuel cell for a cleaner and sustainable future. In the modeled work, a solid oxide fuel cell, a gas turbine, an organic Rankine cycle, a Kalina cycle with ejector, a hydrogen generation and storage process, a wood steaming plant, and an ammonia production system is integrated, to generate useful products. Detailed thermodynamic modeling is performed through energy and exergy methods, to determine the performance of the advised system and subsystem. Moreover, energy efficiency, exergy efficiency, and exergy destruction analyses methods are applied to each sub-plant and the whole system separately. In addition, parametric research is carried out to examine the effects of modifying key parameters on the plant's and subsystems' performance. Looking at the analysis results, the amount of the hydrogen and ammonia generation capacities of this work are 0.0085 kgs?1and 0.2023 kgs?1, respectively. In addition, the modeled power plant produces a power rate of about 20,180 kW. As a result, this proposed study is calculated to have 61.04% energy efficiency, and 57.13% exergy efficiency. 相似文献
106.
金川集团铜业有限公司在用的两套制酸系统530 kt/a和300 kt/a分别建于2005年和2006年,两套系统原设计中转化工序全部采用“3+1”双转双吸的转化流程,2012年合成炉系统大修中率先将530 kt/a系统转化工序升级为“3+2”流程,并增加了配套的余热锅炉,但制酸系统的净化工序和干吸工序并未升级,导致整套系统在匹配性能提升方面存在短板。采用“回”型喷头布置、水平放置的新型等压捕沫器、“塔-槽一体式”浓酸吸收设备等新技术后,吸收塔的吸收率由99.88%上升至99.9%,酸雾含量减少了至少50%,净化工序酸水排放量降低了40%,制酸系统二段电除雾器出口氟元素含量由1.5 mg/m3降低至0.6 mg/m3,烟气杂质去除率提升了60%,吸收塔循环槽容积提升后,制酸系统处理烟气量增加了0.3×105 m3/h(两系统合计)。 相似文献
107.
“电磁场与电磁波”是多种学科的交叉点,是电子信息、通信技术相关专业的重要理论基础,是电类专业的一门核心基础课程。该课程内容涉及面广、理论抽象、数学分析多,是公认的一门教师难教、学生难学的课程。本文针对“电磁场与电磁波”课程教学实际,尝试利用前沿技术引领课堂教学,对教学模式进行改革与实践。以课程为中心、教师为主导、学生为主体,探索覆盖体系课程融合、课外仿真实践、课程思政、工程案例与科研融入、翻转课堂、线上线下并行等混合教学模式。通过教学模式改革,希望打通课前、课中、课后以及相关课程间的连接通道,帮助学生系统理解和消化电磁场与电磁波的基本理论,充分锻炼学生独立解决实际问题和实践创新的能力。 相似文献
108.
Operator error in diagnosis and execution of task have significant impact on Nuclear Power Plant (NPP) safety. These human errors are classified as mistakes (rule base and knowledge based errors), slip (skill based) and lapses (skill based). Depending on the time of occurrence, human errors have been categorized as i) Category ‘A’ (Pre-Initiators): actions during routine maintenance and testing wherein errors can cause equipment malfunction ii) Category ‘B’ (Initiators): actions contributing to initiating events or plant transients iii) Category ‘C’ (Post-Initiators): actions involved in operator response to an accident. There have been accidents in NPPs because of human error in an operator's diagnosis and execution of an event. These underline the need to appropriately estimate HEP in risk analysis. There are several methods that are being practiced in Probabilistic Safety Assessment (PSA) studies for quantification of human error probability. However, there is no consensus on a single method that should be used. In this paper a method for estimating HEP is proposed which is based on simulator data for a particular accident scenario. For accident scenarios, the data from real NPP control room is very sparsely available. In the absence of real data, simulator based data can be used. Simulator data is expected to provide a glimpse of probable human behavior in real accident situation even though simulator data is not a substitute for real data. The proposed methodology considers the variation in crew performance time in simulator exercise and in available time from deterministic analysis, and couples them through their respective probability distributions to obtain HEP. The emphasis is on suitability of the methodology rather than particulars of the cited example. 相似文献
109.
目前,大学计算机基础课程不仅是计算机专业的必修课目,也是非计算机专业必修公共课的重要组成部分。计算机水平的高低直接影响着学生毕业后的就业,在大学教育中占有重要的地位。然而,我国的大学计算机基础课程中还存在一些问题。本文将通过分析大学计算机基础课程的现状,进而提出大学计算机基础课程教学改革的实践,着重分析在更新教学观念、优化教学内容、革新教学方式、完善考核方式、增强激励机制等方面的实践,力求为找到进一步提高计算机基础课程教学质量的方法提出思路及实践参考。 相似文献
110.