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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.
Through a facile hydrothermal method, we have successfully prepared Ti3C2/Bi2.15WO6 (TC/BWO) composite, and systematically investigated their reactivity for the photocatalytic reduction of Cr(VI) under visible light. X-ray diffraction and Raman analysis confirm the formation of heterostructure between Bi2.15WO6 and Ti3C2. The resultant 7TC/BWO composite exhibits enhanced photoactivity toward Cr(VI) reduction. After 120 min irradiation, the conversion of Cr(VI) reaches 92.5% with the quasi-first-order kinetic constant of k = 0.0145 min?1, which is higher than that of pure BWO (30% and k = 0.0005 min?1). The electrochemical and photoluminescent characterization confirm that the introduction of Ti3C2 is conducive to the separation of carriers, thus significantly improves the photocatalytic performance of TC/BWO. Furthermore, the radical capture experiments verify that the electrons are important for enhancing reduction of Cr(VI) to Cr(III). As a result, this research provides a comprehensive understanding of the reduction of Cr(VI) by TC/BWO composite under visible light.  相似文献   
3.
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   
4.
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   
5.
The fuel cell/battery durability and hybrid system stability are major considerations for the power management of fuel cell hybrid electric bus (FCHEB) operating on complicated driving conditions. In this paper, a real time nonlinear adaptive control (NAC) with stability analyze is formulated for power management of FCHEB. Firstly, the mathematical model of hybrid power system is analyzed, which is established for control-oriented design. Furthermore, the NAC-based strategy with quadratic Lyapunov function is set up to guarantee the stability of closed-loop power system, and the power split between fuel cell and battery is controlled with the durability consideration. Finally, two real-time power management strategies, state machine control (SMC) and fuzzy logic control (FLC), are implemented to evaluate the performance of NAC-based strategy, and the simulation results suggest that the guaranteed stability of NAC-based strategy can efficiently prolong fuel cell/battery lifespan and provide better fuel consumption economy for FCHEB.  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.
Highly-efficient and stable non-noble metal electrocatalysts for overcoming the sluggish kinetics of oxygen evolution reaction (OER) is urgent for water electrolysis. Biomass-derived biochar has been considered as promising carbon material because of its advantages such as low-cost, renewable, simple preparation, rich structure, and easy to obtain heteroatom by in-situ doping. Herein, Ni2P–Fe2P bimetallic phosphide spherical nanocages encapsulated in N/P-doped pine needles biochar is prepared via a simple two-step pyrolysis method. Benefiting from the maximum synergistic effects of bimetallic phosphide and biochar, high conductivity of biochar encapsulation, highly exposed active sites of Ni2P–Fe2P spherical nanocages, rapid mass transfer in porous channels with large specific surface area, and the promotion in adsorption of reaction intermediates by high-level heteroatom doping, the (Ni0.75Fe0.25)2P@NP/C demonstrates excellent OER activity with an overpotential of 250 mV and a Tafel slope of 48 mV/dec at 10 mA/cm2 in 1 M KOH. Also it exhibits a long-term durability in 10 h electrolysis and its activity even improves during the electrocatalytic process. The present work provides a favorable strategy for the inexpensive synthesis of biochar-based transition metal electrocatalysts toward OER, and improves the water electrolysis for hydrogen production.  相似文献   
8.
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   
9.
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   
10.
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