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1.
夏敏浩  赵万剑  王骏 《中州煤炭》2022,(7):189-194,200
为了提高配电网差异化节能降耗效果,解决现有潜力评估方法存在的应用性能差的问题,提出碳中和背景下配电网差异化节能降耗潜力优化评估方法。根据配电网的空间结构,构建相应的等值电路模型。在该模型下,从设备损耗和运行附加损耗2个方面计算配电网的损耗量。根据损耗量计算结果,确定配电网差异化碳中和节能降耗方式。从静态和动态2个角度设置潜力评估指标,通过指标数据处理、指标权重求解等步骤,得出配电网差异化节能降耗潜力的综合量化评估结果。将设计潜力评估方法应用到配电网的差异化节能降耗改造工作中,能够有效降低配电网的实际线损量、降低区域损耗费用,并具有较高的应用价值。  相似文献   
2.
深凹露天矿山由于其特殊的结构,爆破产生的炮烟扩散稀释较为困难,严重危害生产作业人员的生命安全与健康。基于实际矿山构建了深凹露天矿山的二维物理及数学模型,采用非稳态数值分析方法研究了不同爆破位置下,深凹露天矿山采坑内爆破炮烟的扩散规律。研究结果表明:不同爆破位置下,露天采坑内均出现复环流,爆破点位置是影响露天采坑内风流结构特征的重要因素;露天采坑内的炮烟最高浓度均随着时间变化而逐渐下降,但下降的速率逐步减小,呈现三个阶段的下降趋势;爆破位置位于背风侧时露天采坑内的炮烟最高浓度和降至安全浓度所需时间远高于迎风侧三个爆破位置;随着背风侧爆破点距采坑底部距离的减小,炮烟最高浓度及降至安全浓度所需时间先降低后增加,炮烟最高浓度及降至安全浓度所需时间随着迎风侧爆破位置距采坑底部距离的减小而增加。研究结果对于指导深凹露天矿山企业合理组织爆破后的生产作业和保障作业人员安全具有重要意义。  相似文献   
3.
许德骅  熊德天  吴昊 《包装工程》2022,43(4):189-196, 250
目的 针对章水泉竹艺非物质文化遗产在目前所遭遇的传承困境,利用数字媒体技术与互联网平台,打造推动其产品创新与文化传承的APP,助力其文化与产品的传播与推广,进而为湖北地区的非遗文化发展提供参考。方法 从章水泉竹器的本源出发,对其主要产品门类、工艺特点与艺术形式进行整理与分类,分析制约其传承与发展的主要原因,进而提出设计策略,并通过数字化传承、合作创新、成果推广3个策略模块针对性地进行APP设计。结论 章水泉竹艺APP设计通过利用数字媒体技术与互联网平台优势,将其历史与工艺资料进行数字化保存与展示,实现了文化保护功能;将其传统技艺与新锐设计思维通过线上平台进行融合与创新,实现了设计创新功能;将其制作流程与文化精髓通过直播与精准推送展现于公众视野,实现了产品推广功能。最终,为章水泉竹艺的传承与推广提供了新的路径。  相似文献   
4.
电子雷管技术提高了爆破器材的本质安全。通过对电子雷管技术发展历程的介绍,对其推广应用的可行性进行了深入分析,论述了电子雷管技术的推广应用对爆破器材安全管理工作的促进作用,并提出了今后推广应用中还需加强的工作。  相似文献   
5.
Natural hydrogen exploration is now active in various places of the world. Onshore, correlation between natural H2 generation and the presence of iron rich rocks especially from Archean and Neoproterozoic cratons have been observed. Emanations and accumulations of H2 have already been confirmed in such geological settings in Australia, South Africa and Brazil. The geological similitude and the presence of numerous sub circular depressions that are a good proxy for hydrogen emanations suggest that hydrogen resources may also exist in Namibia. We present here the results of a data acquisition campaign which allowed us to confirm the presence of natural hydrogen in this country in the vicinity of Neoproterozoic Banded Iron Formation. The H2 content in the soil, as in Brazil, is variable within the depressions in time and space and is particularly time sensitive across the day. Comparison of the H2 signal versus time within these two regions shows a similar behavior of the soils with an increase of the H2 flow at the middle of the day. In addition, these new data allow us to better constrain the morphological characteristics of such H2-emiting depressions. By using satellite images and digital elevation model we propose a new proxy to differentiate potentially H2-emiting features from other type of depressions such as Salt Pan. The Landsat multispectral images and their processing through NDVI and SAVI indexes, that highlight a ring of healthy vegetation around the sub circular area with scarce vegetation already observed appear able to discriminate between H2 emitting structures and other soft depressions.  相似文献   
6.
To improve the safety of wet dust removal systems for processing magnesium-based alloys, a new method is proposed for preventing hydrogen generation. In this paper, hydrogen generation by Mg–Zn alloy dust was inhibited with six common metal corrosion inhibitors. The results showed that sodium dodecylbenzene sulfonate was the best hydrogen inhibitor, while CeCl3 enhanced hydrogen precipitation. The film-forming stability of sodium dodecylbenzene sulfonate was tested with different contents, temperatures, Cl? concentrations and perturbation rates. The results showed that this inhibitor formed stable protective films on the surfaces of Mg–Zn alloy particles, and adsorption followed the Langmuir adsorption model.  相似文献   
7.
The H2 storage properties of isoreticular metal-organic framework materials (IRMOFs), MOF-5 and IRMOF-10, impregnated with different numbers and types of heterogeneous C48B12 molecules were investigated using density functional theory and grand canonical Monte Carlo (GCMC) calculations. The excess hydrogen adsorption isotherms of IRMOFs at 77 K within 20 bar indicate that suitable number and type of C48B12 molecules play a crucial role in improving the H2 storage properties of IRMOFs. Among the studied pure and nC48B12 (n = 1, 2, 4, 8) in Ci symmetry impregnating into MOF-5, at 77 K under 6 bar, MOF-5-4C48B12 with a 3.5 wt% and 29.9 g/L hydrogen storage density, and at 77 K under 12 bar, the pure MOF-5 with a 4.9 wt% and 31.0 g/L hydrogen storage density has the best hydrogen storage properties. Whereas, among the studied pure and nC48B12 (n = 1, 2, 4, 8) in S6 symmetry impregnating into IRMOF-10, IRMOF-10-8C48B12 always shows the best hydrogen storage properties among the pure and C48B12-impregnated IRMOF-10 at 77 K within 20 bar. IRMOF-10-8C48B12 has a 6.0 wt% and 34.6 g/L hydrogen storage density at 77 K under 6 bar, and has a 7.1 wt% and 41.4 g/L hydrogen storage density at 77 K under 12 bar. The confinement effect of IRMOFs on C48B12 molecules, and steric hindrance effect of C48B12 molecules on IRMOFs mainly affects the H2 uptake capacity by comparing the absolute H2 molecules in individual IRMOFs units, C48B12 molecules, and IRMOFs-nC48B12 compounds. The absolute hydrogen adsorption profiles show that eight C48B12 molecules impregnating into MOF-5 can exert obvious steric effects for H2 adsorption. The saturated gravimetric and volumetric H2 densities of IRMOF-10-8C48B12 higher than those of MOF-5-8C48B12 due to with larger free volume.  相似文献   
8.
In the present work, the heating performance of a new system combined with a new modified baseboard radiator and fan coil is investigated. Using longitudinal fins with special geometry and also forced airflow at the end of the system causes that at the lower inlet water temperature compared with the conventional models, higher heat output rate be obtained. The heat output rate of the new modified system is obtained by experimental metrology based on the European Standard No. EN-442. Temperature and velocity distribution in the room space is done by simulation of the modified system in the Flovent software. Computational fluid dynamics (CFD) results are validated against experimental results and there is a good agreement between them. Also, the energy consumption of the system during the winter season is calculated in TRANSYS software. Experimental results show that the heat output rate of a new modified heating system with inlet water temperature in the range of 45–55°C is on average 4.17 times higher compared with the conventional model. CFD simulation also showed that the combined system provides good thermal comfort conditions. Energy consumption of the new system reduced about 13% compared with conventional models.  相似文献   
9.
In the present paper, therapeutic treatment of infected tumorous cells has been studied through mathematical modeling and simulation of heat transfer in tissues by using a nonlinear dual-phase lag bioheat transfer model with Dirichlet boundary condition. The components of volumetric heat source in this model such as blood perfusion and metabolism are assumed experimentally validated temperature-dependent function, which gives more accurate temperature distribution in tissues through this model. We have used the finite difference and RK (4, 5) techniques of numerical methods to solve the proposed problem and obtained the exact solution in a particular case. After comparison, we got a good agreement between them. We have used dimensionless quantities throughout this paper. The effect of relaxation and thermalization time with respect to dimensionless temperature distribution has been analyzed in the treatment process.  相似文献   
10.
Efficient electricity price forecasting plays a significant role in our society. In this paper, a novel influencer-defaulter mutation (IDM) mutation operator has been proposed. The IDM operator has been combined with six well-known optimization algorithms to create mutated optimization algorithms whose performance has been tested on twenty-four standard benchmark functions. Further, the artificial neural network is integrated with mutated optimization algorithms to solve the electricity price prediction problem. The policymakers can identify appropriate variables based on the predicted prices to help future market planning. The statistical results prove the efficacy of the IDM operator on the recent optimization algorithms.  相似文献   
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