Excel电子表格在氢计算中的应用

介绍用Excel的计算功能根据经验式计算氢含量。

660MW超超临界机组发电机漏氢量计算及漏点处理

发电机漏氢量直接影响机组的安全运行,是汽轮发电机组运行的主要指标之一,所以准确计算出发电机组漏氢量非常重要。主要介绍淮北申皖发电有限公司660MW超超临界机组发电机组调试、运行时漏氢量的计算及氢气漏点的查找、消除工作。

燃料电池汽车的氢耗分析模型与应用

为便于定量分析燃料电池汽车的氢耗影响因素和整车氢耗潜力,文中基于燃料电池汽车行驶时内部的能量流动关系,首先定义平均综合传动效率并提出理论氢耗计算分析模型.通过对氢耗的多种影响因素进行分析,进一步得到理论氢耗增量模型.最后基于advi-sor自带的燃料电池汽车模型,通过理论和仿真分析量化了滚动阻力系数、传动系机械效率、电机效率、燃料电池效率对整车经济性的影响.此外,基于各影响因素未来可能达到的极限状态,通过仿真得氢耗潜力为0.6 kg/100 km.不同因素的量化分析和氢耗潜力的确定不仅对燃料电池汽车动力系统前期研发有重要指导意义,而且在实车开发期间可为部件选择和参数标定提供优化方向.

临氢系统典型材料的充氢和脱氢行为研究

为给加氢装置停工过程恒温脱氢操作提供一定技术指导,开展了7种典型材料的充氢和脱氢试验,测试了充氢前后材料力学性能的变化,观察了充氢前后材料的微观组织和断口形貌的变化,通过计算室温下材料的氢扩散系数及测量不同脱氢工艺下材料的氢含量来确定材料的氢渗透状态。同时,开展了不同温度下碳钢和不锈钢材料脱氢的计算机模拟,研究了碳钢和不锈钢放氢曲线随温度变化的规律。综合上述试验和计算机模拟,揭示了材料渗氢状况的危害性并验证了恒温脱氢的必要性。

密闭室法测定汽车蒸发污染排放物试验结果的计算

指出在使用可变容积密闭室法进行汽车蒸发污染排放及相关试验时,由于标准中所提供的计算公式存在明显缺陷而使计算结果产生一定的偏差。根据热力学定律及试验设备的工作原理对计算公式进行了推导,并进行了24h密闭室丙烷喷射试验,试验结果与实际情况完全相符。

含铜铸钢件塑性不合原因分析及改进措施

对含铜铸钢件力学性能检测试样断口宏观形貌、微观形貌、金相组织、化学成分等进行分析,确定该含铜铸钢件塑性不合的原因,提出改进措施。经扩氢理论计算和生产实践验证,采用对应措施后,该含铜铸钢件的塑性得到改善提升。

First-principles study of intrinsic defects,dopants and dopant-defect complexes in LiBH_4

A first-principles study was reported based on density functional theory of hydrogen vacancy,metal dopants,metal dopant-vacancy complex in LiBH4,a promising material for hydrogen storage.The formation of H vacancy and metal doping in LiBH4 is difficult,and their concentrations are low.The presence of one kind of defect is helpful to the formation of other kind of defect.Based on the analysis of electronic structure,the improvement of the dehydrogenating kinetics of LiBH4 by metal catalysts is due to the weaker bonding of B—H and the new metal-like system,which makes H atom diffuse easily;H vacancy accounts for a trace amount of BH3 release during the decomposing process of LiBH4;metal dopant weakens the strength of B—H bonds,which reduces the dehydriding temperature of LiBH4.The roles of metal and vacancy in the metal dopant-vacancy complex can be added in LiBH4 system.

Linear and Nonlinear Optical Absorptions of a Hydrogenic Donor in a Quantum Dot Under a Magnetic Field

The linear and nonlinear optical properties of a hydrogenic donor in a disc-like parabolic quantum dot in the presence of an external magnetic field are studied. The calculations were performed within the effective mass approximation, using the matrix diagonalization method and the compact density-matrix approach. The linear and nonlinear optical absorption coefficients between the ground （L =0） and the first excited state （L = 1） have been examined based on the computed energies and wave functions. We find that the linear, nonlinear third-order, and total optical absorption coefficients are strongly affected by the confinement strength of QDs, the external magnetic field, and the incident optical intensity.

Hydrogenation of 2‐ethylanthraquinone with bimetallic monolithic catalysts: An experimental and DFT study

We studied the hydrogenation of 2‐ethylanthraquinone（eAQ） over Pd/SiO2/COR（COR = cordierite） monometallic and Pd‐M/SiO2/COR（M = Ni, Fe, Mn, and Cu） bimetallic monolithic catalysts, which were prepared by the co‐impregnation method. Detailed investigations showed that the particle sizes and structures of the Pd‐M（M = Ni, Fe, Mn, and Cu） bimetallic monolithic catalysts were great‐ly affected by the second metal M and the mass ratio of Pd to the second metal M. By virtue of the small particle size and the strong interaction between Pd and Ni of Pd‐Ni alloy, Pd‐Ni bimetallic monolithic catalysts with the mass ratio of Pd/Ni = 2 achieved the highest H2O2 yield（7.5 g/L） and selectivity（95.3%）. Moreover, density functional theory calculations were performed for eAQ ad‐sorption to gain a better mechanistic understanding of the molecule‐surface interactions between eAQ and the Pd（1 1 1） or PdM（1 1 1）（M = Ni, Fe, Mn, and Cu） surfaces. It was found that the high activity of the bimetallic Pd‐Ni catalyst was a result of strong chemisorption between Pd3Ni1（1 1 1） and the carbonyl group of eAQ.

Expanded Porphyrin Nanosheet for Metal-Free Photocatalytic Water Splitting Using Visible Light

Photocatalytic water splitting to generate hydrogen gas is an ideal solution for environmental pollution and unsustainable energy issues.In the past few decades,many efforts have been made to increase the efficiency of hydrogen production.One of the most important ways is to achieve light absorption in the visible range to improve the conversion efficiency of solar energy into chemical energy,but it still presents great challenges.We here predicted a novel organic film,which can be obtained by polymerizing HTAP molecules,as an ideal material for photocatalytic water splitting.Based on firstprinciples calculations and Born-Oppenheimer quantum molecular dynamic simulations,the metal-free two-dimensional nanomaterial has been proven to be structurally stable,with a direct band gap of 2.12 e V,which satisfies the requirement of light absorption in the visible range.More importantly,the conduction bands and valence bands completely engulf the redox potentials of water,making the film be a promising photocatalyst for water splitting.This construction method through the topological periodicity of organic molecules provides a design scheme for the photocatalyst for water splitting.

Theoretical Studies on the Reaction Kinetics of Methyl 2-Furoate with Hydroxyl Radical

Methyl 2-furoate(FAME2)is a model for the potential renewable biofuel of dimethyl furan-2,5-dicarboxylate,with the development of its new synthesis method.The potential energy surfaces of H-abstractions and OHadditions between FAME2 and hydroxyl radical(OH)were studied using CCSD(T)/CBS//M062X/ccpVTZ.The subsequent isomerization and decomposition reactions were also determined for the primary radicals produced.The results showed that H-abstraction on the branched methyl group was the dominant channel and that the OH-addition reactions on the furan ring had a significant pressure dependency.The rate coefficients presented here provide important kinetic data to support future improvement of the combustion mechanism of FAME2,and present a sound basis for further research into practical fuels.

Mechanism investigation of PtPd decorated Zn_(0.5)Cd_(0.5)S nanorods with efficient photocatalytic hydrogen production combining with kinetics and thermodynamics

Different components of PtPd bimetallic cocatalysts modified Zn_(0.5)Cd_(0.5)S nanorods have already been designed and prepared in this study.The obtained hybrid photocatalysts were tested and characterized by XPS,ICP-OES and UV-Vis spectra,TEM and EDX tools.Such characterizations can prove the formation of PtPd bimetallic alloy particles in hybrid catalysts.Under visible light illumination,an outstanding hydrogen producing rate of 9.689mmol·g^(-1)·h^(-1) and a high AQY efficiency up to 10.43%at 420 nm are achieved in this work.In addition,thermodynamics(DFT calculations)and kinetics(Photoluminescence emission,photocurrent responses,electrochemical impedance spectroscopy and surface photovoltage spectra)investigations illustrate that PtPd bimetallic alloy has similar catalytic thermodynamic properties to Pt,which can greatly boost the charge separation and speed up the charge transfer,and decrease the activation energy of H2 generation.Notably,the calculation data suggests that Pt is thermodynamically favorable,while PtPd alloy is kinetically beneficial to H_(2)production,which can be ascribed to the higher activity of PtPd/Zn_(0.5)Cd_(0.5)S than Pt/Zn_(0.5)Cd_(0.5)S.This work can propose a fresh perspective for preparing high efficiency hybrid photocatalysts.

Hydrogen storage properties of magnesium hydride catalyzed by Ni-based solid solutions

The Ni−25%X(X=Fe,Co,Cu,molar fraction)solid solutions were prepared and then doped into MgH_(2) through high-energy ball milling.The initial dehydrogenation temperatures of MgH_(2)/Ni−25%X composites are all decreased by about 90℃relative to the as-milled pristine MgH_(2).The Ni−25%Co solid solution exhibits the most excellent catalytic effect,and the milled MgH_(2)/Ni−25%Co composite can release 5.19 wt.%hydrogen within 10 min at 300℃,while the as-milled pristine MgH_(2) can only release 1.78 wt.%hydrogen.More importantly,the dehydrogenated MgH_(2)/Ni−25%Co composite can absorb 5.39 wt.%hydrogen at 275℃within 3 min.The superior hydrogen sorption kinetics of MgH_(2)/Ni−25%Co can be ascribed to the actual catalytic effect of in-situ formed Mg_(2)Ni(Co)compounds.First-principles calculations show that the hydrogen absorption/desorption energy barriers of Mg/MgH_(2) systems decrease significantly after doping with transition metal atoms,which interprets well the improved hydrogen sorption properties of MgH_(2) catalyzed by Ni-based solid solutions.

An improved self-adaptive membrane computing optimization algorithm and its applications in residue hydrogenating model parameter estimation

In order to solve the non-linear and high-dimensional optimization problems more effectively, an improved self-adaptive membrane computing(ISMC) optimization algorithm was proposed. The proposed ISMC algorithm applied improved self-adaptive crossover and mutation formulae that can provide appropriate crossover operator and mutation operator based on different functions of the objects and the number of iterations. The performance of ISMC was tested by the benchmark functions. The simulation results for residue hydrogenating kinetics model parameter estimation show that the proposed method is superior to the traditional intelligent algorithms in terms of convergence accuracy and stability in solving the complex parameter optimization problems.

High Accuracy Calculation for Excited-State Energies of H Atoms in a Magnetic Field

Using the recently developed finite-basis-set method with B splines, excited states of H atoms in a magnetic field have been calculated. Energy levels are presented for the ten excited states, 2so, 3d＇0, 3po, 3p-1, 3d_1, 4d-1, 3d-2, 4d-2, 4f-2 , and 5f-2 as a function of magnetic field strengths with a range from zero up to 2.35 × 10^6 T. The obtained results are compared with available high accuracy theoretical data reported in the literature and found to be in excellent agreement. The comparison also shows that the current method can produce energy levels with an accuracy higher than the existing high accuracy method [Phys. Rev. A 54 （1996） 287]. Here high accuracy energy levels are for the first time reported for the 3d＇0, 4d-1, 4d-2, 4f-2, and 5f-2 states.

Structural and Electronic Properties of Li2Mg（NH）2 for Hydrogen Storage： First-principles Study

The structural and electronic properties of Li2Mg（NH）2 for hydrogen storage have been studied by first-principles calculation. The optimal unit cell parameters and the distance of N-H are determined, which are in good agreement with the experimental data. The bulk modules and the energies of zero pressure are obtained by using Murnaghan equation of states. The results show that the α-Li2Mg（NH）2 is a ground state configuration. The overlap population analysis shows that the N-Li/Mg ionic characteristics and N-H interaction of αphase are weaker than those of βphase. The valence band is dominated by the presence of N s and p states, hybridized with the H s state.

Thermodynamic Calculation on the Formation of Titanium Hydride

A modified Miedema model, using interrelationship among the basic properties of elements Ti and H, is employed to calculate the standard enthalpy of formation of titanium hydride TiHx （1≤x≤2）. Based on Debye theories of solid thermal capacity, the vibrational entropy, as well as electronic entropy, is acquired by quantum mechanics and statistic thermodynamics methods, and a new approach is presented to calculate the standard entropy of formation of TiH2. The values of standard enthalpy of formation of TiHx decrease linearly with increase of x. The calculated results of standard enthalpy, entropy, and free energy of formation of TiH2 at 298.16 K are -142.39 kJ/mol, -143.0 J/（mol·K） and -99.75 kJ/mol, respectively, which is consistent with the previously-reported data obtained by either experimental or theoretical calculation methods. The results show that the thermodynamic model for titanium hydride is reasonable.

First-Principles Study of Ultrathin Molybdenum Sulfides Nanowires:Electronic and Catalytic Hydrogen Evolution Properties

Molybdenum sulfides nanomaterials, such as one-dimensional (1D) nanotubes, nanoribbons, and two-dimensional (2D) nanosheets, have attracted intensive research interests for their novel electronic, optical, and catalytic properties. On the basis of first-principles calculation, here, we report a new series of 1D ultrathin molybdenum sulfides nanowires, including Mo2S6、Mo3S6 and Mo6S10 nanowires. Our results demonstrate that these ultrathin nanowires are both thermal and lattices dynamically stable, confirmed with the calculated phonon spectrum and Born-Oppenheimer molecular dynamic simulation at the temperature up to 600 K. The calculated elastic constant is 21.33, 103.22, and 163.00 eV/■ for Mo2S6, Mo3S6, and Mo6S10 nanowires, respectively. Mo2S6 and Mo3S6 nanowires are semiconductors with band gap of 1.55 and 0.46 eV, while Mo6S10 nanowires is metal, implying their potential applications in electronics and optoelectronics. In particular, ultrathin molybdenum sulfides nanowires can be used as catalysts for hydrogen evolution reaction. The calculated Gibbs free energy change for hydrogen evolution is about -0.05 eV for Mo2S6 nanowire, comparable with those of Pt and H-MoS2. The prediction of these 1D molybdenum sulfides nanowires may enrich the 1D family molybdenum sulfides and make a supplement to understand the high performance of hydrogen evolution reaction in transition-metal dichalcogenides.

Computer Data Processing of the Hydrogen Peroxide Decomposition Reaction

Two methods of computer data processing, linear fitting and nonlinear fitting, are applied to compute the rate constant for hydrogen peroxide decomposition reaction. The results indicate that not only the new methods work with no necessity to measure the final oxygen volume, but also the fitting errors decrease evidently.

Experimental Study on Refinery Gas Desulfurization Using Gas-Liquid Membrane Contactor

Gas-liquid contactors equipped with polytetrafluoroethylene （PTFE） or polypropylene （PP） hydrophobic membranes were applied for removal of sulfur dioxide from refinery gas. Pure water, NaOH solution and MDEA were adopted as the absorbents. The performance of the two kinds of membranes for separation of SO2 was evaluated in terms of the concentration of absorbent solution, the concentration of SO2, and the feed flow rate. The efficiency for removal of SO2 increased with an increasing absorbent concentration. Upon increasing the concentration of SO2 and the feed flow rate, the desulfurization efficiency was decreased.