As a new clean energy resource in the 21st century, natural gas hydrate is considered as one of the most promising strategic resources in the future. This paper, based on the research progress in exploitation of natural gas hydrate (NGH) in China and the world, systematically reviewed and discussed the key issues in development of natural gas hydrate. From an exploitation point of view, it is recommended that the concepts of diagenetic hydrate and non-diagenetic hydrate be introduced. The main factors to be considered are whether diagenesis, stability of rock skeleton structure, particle size and cementation mode, thus NGHs are divided into 6 levels and used unused exploitation methods according to different types. The study of the description and quantitative characterization of abundance in hydrate enrichment zone, and looking for gas hydrate dessert areas with commercial exploitation value should be enhanced. The concept of dynamic permeability and characterization of the permeability of NGH by time-varying equations should be established. The ‘Three-gas co-production’ (natural gas hydrate, shallow gas, and conventional gas) may be an effective way to achieve early commercial exploitation. Although great progress has been made in the exploitation of natural gas hydrate, there still exist enormous challenges in basic theory research, production methods, and equipment and operation modes. Only through hard and persistent exploration and innovation can natural gas hydrate be truly commercially developed on a large scale and contribute to sustainable energy supply.

甲烷水合物法是储存和运输甲烷的一种有效的方法。在所有的水合物促进剂中，均相的表面活性剂水溶液，特别是十二烷基硫酸钠(SDS)比非均相的颗粒效果更好，它的反应速率更快，储气倍数更高，更加稳定。但是对SDS溶液来讲，水合物分解过程产生的泡沫很难避免。本文考察了五种氟表面活性剂，全氟丁基磺酸钾(PBS)、全氟己基磺酸钾(PHS)、全氟辛基磺酸钾(POS)、全氟辛基磺酸铵(AOS)、全氟辛基磺酸四乙基胺(TOS)促进水合物生成的能力。实验发现，PBS 和PHS都能在30分钟内达到150 (V/V)的储气倍数，这要优于SDS。同时考察了阳离子和碳链长度的影响。PBS、PHS和POS在水合物分解过程中没有产生泡沫，因此在水合物放大生产中具有很好的应用前景。

液化天然气因其高效、清洁、安全等优点在能源石油化工工业中广泛应用，在运输和储存中有较多优势的液化天然气在使用中需要进行气化处理，中间介质气化器由于其结构紧凑、水质要求低、不结冰等优势属于LNG接收站主要气化设备之一。中间介质气化器由三个管壳式换热器组成，分别为冷凝器、蒸发器以及调温器。冷凝器与蒸发器共用一个壳层，LNG与海水通过壳层里的中间介质间接换热，中间介质可以是丙烷、乙二醇、丙烯等。论文作者建立了一维分布参数模型，对各种工况下的IFV性能进行了研究，对额定工况的研究中，完成了一部分尺寸参数的优化。对极端工况的研究中，阐述了IFV的局限性，并给出了应对策略；此外，作者还讨论了调温器在IFV中的重要性，以及缺少调温器的IFV在一些特殊极端条件中的应用。

Natural gas hydrate is an alternative energy source with a great potential for development. The addition of surfactants has been found to have practical implications on the acceleration of hydrate formation in the industrial sector. In this paper, the mechanisms of different surfactants that have been reported to promote hydrate formation are summarized. Besides, the factors influencing surfactant-promoted hydrate formation, including the type, concentration, and structure of the surfactant, are also described. Moreover, the effects of surfactants on the formation of hydrate in pure water, brine, porous media, and systems containing multiple surfactants are discussed. The synergistic or inhibitory effects of the combinations of these additives are also analyzed. Furthermore, the process of establishing kinetic and thermodynamic models to simulate the factors affecting the formation of hydrate in surfactant-containing solutions is illustrated and summarized.

微米/纳米结构在调节材料的辐射性能中起着关键作用，并且已被应用于高温能量转换系统以提高性能 。在各种辐射特性中，光谱发射率对于设计和分析用作辐射吸收器或发射器的材料至关重要。本文概述了使用直接和间接方法的光谱发射率测量技术。此外，还介绍了几种微/纳米结构，并特别强调了为表征高温应用（例如，太阳能转换和热光电设备）中的工程微/纳米结构而开发的发射仪。此外，还总结了不同材料的实验设施和测量结果。此外，还概述了开发用于实际应用的仪器和微/纳米结构表面的未来前景。本文为微观/纳米结构在高温能量转换工程中的应用提供了全面的信息来源。

Recently, renewable energy resources and their impacts have sparked a heated debate to resolve the Australian energy crisis. There are many projects launched throughout the country to improve network security and reliability. This paper aims to review the current status of different renewable energy resources along with their impacts on society and the environment. Besides, it provides for the first time the statistics of the documents published in the field of renewable energy in Australia. The statistics include information such as the rate of papers published, possible journals for finding relative paper, types of documents published, top authors, and the most prevalent keywords in the field of renewable energy in Australia. It will focus on solar, wind, biomass, geothermal and hydropower technologies and will investigate the social and environmental impacts of these technologies.

The key technologies of liquefied hydrogen have been developing rapidly due to its prospective energy exchange effectiveness, zero emissions, and long distance and economic transportation. However, hydrogen liquefaction is one of the most energy-intensive industrial processes. A small reduction in energy consumption and an improvement in efficiency may decrease the operating cost of the entire process. In this paper, the detailed progress of design and optimization for hydrogen liquefaction in recent years are summarized. Then, based on the refrigeration cycles, the hydrogen liquefaction processes are divided into two parts, namely precooled liquefaction process and cascade liquefaction process. Among the existing technologies, the SEC of most hydrogen liquefaction processes is limited in the range of 5–8 kWh/ {\mathrm{k}\mathrm{g}}_{{\mathrm{L}\mathrm{H}}_2} : liquid hydrogen). The exergy efficiencies of processes are around 40% to 60%. Finally, several future improvements for hydrogen liquefaction process design and optimization are proposed. The mixed refrigerants (MRs) as the working fluids of the process and the combination of the traditional hydrogen liquefaction process with the renewable energy technology will be the great prospects for development in near future.

Presently, the global search for alternative renewable energy sources is rising due to the depletion of fossil fuel and rising greenhouse gas (GHG) emissions. Among alternatives, hydrogen (H₂) produced from biomass gasification is considered a green energy sector, due to its environmentally friendly, sustainable, and renewable characteristics. However, tar formation along with syngas is a severe impediment to biomass conversion efficiency, which results in process-related problems. Typically, tar consists of various hydrocarbons (HCs), which are also sources for syngas. Hence, catalytic steam reforming is an effective technique to address tar formation and improve H₂ production from biomass gasification. Of the various classes in existence, supported metal catalysts are considered the most promising. This paper focuses on the current researching status, prospects, and challenges of steam reforming of gasified biomass tar. Besides, it includes recent developments in tar compositional analysis, supported metal catalysts, along with the reactions and process conditions for catalytic steam reforming. Moreover, it discusses alternatives such as dry and autothermal reforming of tar.

液氢由于储能密度高而受到广泛关注。由于液氢沸点低（20 K），蒸发损失是其贮存过程中面临的一个突出问题，因而高效绝热技术是目前液氢贮存研究中的一个重要关注点。玻璃微珠由于表观热导率低，安装速度快（与多层材料相比，可以在短时间内注入）和维护简单等特点，成为一种有应用前景的绝热材料。本文提出一种由玻璃微珠和自蒸发气冷屏组成的新型低温绝热系统。建立了一个复合被动绝热模型对玻璃微珠和自蒸发气冷屏的耦合传热特性进行分析。结果表明，组合使用玻璃微珠和自蒸发气冷屏可以有效减少液氢贮箱的漏热。当冷屏数量从1个增加到3个，贮箱漏热分别减少了57.36％，65.29％和68.21％。玻璃微珠的另一个显著优点是其绝热性能对真空度的变化不敏感。当真空度从10⁻³ Pa升高到1 Pa时，贮箱漏热增加只有约20％。当真空度从10⁻³ Pa升高到100 Pa时，与单一使用玻璃微珠方式相比，组合使用玻璃微珠和冷屏的方式可以使漏热降低58.08％–69.84％。

In this paper, the optimization of hydrogen (H₂) production by ammonia borane (NH₃BH₃) over PdCoAg/AC was investigated using the response surface methodology. Besides, the electro-oxidation of NH₃BH₃ was determined and optimized using the same method to measure its potential use in the direct ammonium boran fuel cells. Moreover, the ternary alloyed catalyst was synthesized using the chemical reduction method. The synergistic effect between Pd, Co and Ag plays an important role in enhancement of NH₃BH₃ hydrolysis. In addition, the support effect could also efficiently improve the catalytic performance. Furthermore, the effects of NH₃BH₃ concentration (0.1–50 mmol/5 mL), catalyst amount (1–30 mg) and temperature (20°C–50°C) on the rate of H₂ production and the effects of temperature (20°C–50°C), NH₃BH₃ concentration (0.05–1 mol/L) and catalyst amount (0.5–5 µL) on the electro-oxidation reaction of NH₃BH₃ were investigated using the central composite design experimental design. The implementation of the response surface methodology resulted in the formulation of four models out of which the quadratic model was adjudged to efficiently appropriate the experimental data. A further statistical analysis of the quadratic model demonstrated the significance of the model with a p-value far less than 0.05 for each model and coefficient of determination (R²) of 0.85 and 0.95 for H₂ production rate and NH₃BH₃ electrroxidation peak current, respectively.

煤与生物质耦合发电技术被认为是一种很有前景的节能减排技术。基于生物质气化技术、煤与气化气共燃技术，本文提出了一种新型的煤与生物质间接耦合燃烧系统。为便于比较，还建立了一种传统的煤与生物质直接耦合燃烧系统。本文对直接耦合燃烧系统和间接耦合燃烧系统进行了流程模拟，并分析了两种系统的热力学性能和经济性。分析结果表明，间接耦合燃烧系统的热力学性能稍差，但经济性优于直接耦合燃烧系统。当生物质混合比例为20%时，间接耦合燃烧系统的热效率和㶲效率分别为42.70%和41.14%，系统的内部收益率(IRR)和动态投资回报期(DPP)分别为25.68%和8.56年。燃料和产品的价格波动对间接耦合燃烧系统的经济性有很大的影响。环境影响分析表明，间接耦合系统可以减少NOx的生成，降低环境成本。

Gasification is a thermo-chemical reaction which converts biomass into fuel gases in a reactor. The efficiency of conversion depends on the effective working of the gasifier. The first step in the conversion process is the selection of a suitable feedstock capable of generating more gaseous fuels. This paper analyses the performance of different biomasses during gasification through energy and exergy analysis. A quasi-equilibrium model is developed to simulate and compare the feasibility of different biomass materials as gasifier feedstock. Parametric studies are conducted to analyze the effect of temperature, steam to biomass ratio and equivalence ratio on energy and exergy efficiencies. Of the biomasses considered, sawdust has the highest energy and exergy efficiencies and lowest irreversibility. At a gasification temperature of 1000 K, the steam to biomass ratio of unity and the equivalence ratio of 0.25, the energy efficiency, exergy efficiency and irreversibility of sawdust are 35.62%, 36.98% and 10.62 MJ/kg, respectively. It is also inferred that the biomass with lower ash content and higher carbon content contributes to maximum energy and exergy efficiencies.

The growth-induced effects of financial development have been well-established in the empirical literature, as well as the significance of financial development to energy demand behavior. However, the empirical evidence on the relationship between financial development and energy intensity remains sparse in the literature. Given the multifaceted nature of the effects of financial development, the proposed relationship seems a complex one and warrants an empirical investigation. Using the case of Ghana, this study provides an empirical answer to the question: does financial development lower energy intensity? To provide solid grounds for either rejection or acceptance of the null hypothesis, this study performed several robustness checks. Generally, the evidence revealed that financial development lowers energy intensity. Further, the results revealed that the price of energy, trade liberalization and industry structure play significant roles. These results have important implications for the design of macro energy efficiency policies and the creation of a ‘Green Bank’.

高清晰度摄像机成像是一种重要的技术，它可以可视化钻孔条件并研究与孔清洁过程相关的复杂多相流的物理性质。可视化钻井环空中多相流的主要优势在于，观察者可以轻松地区分流体相，流型和切削床的厚度。本文研究了孔清理过程，该过程涉及将钻屑通过水平环向输送。对这种环形运输涉及的两相（固液）和三相（固液气）流动条件进行了实验模拟，并使用高清摄像机拍摄了图像。分析捕获的图像，确定了许多重要参数，例如不同相的速度，固体床的高度和气泡的大小。测定使用了基于图像分析软件和MATLAB编码的两种不同技术。文章对结果进行了比较以验证图像分析方法。本文开发的可视化技术可直接用于调查有效孔清洁所需的关键条件，以及在钻探的计划阶段和操作阶段优化泥浆程序。特别地，在预测碎屑的输送性能，估算固体床高度，气泡尺寸以及气泡/颗粒的平均速度方面将是有用的。

本文提出了一种提高压缩机性能系数的新方法。 富勒烯（C70）和NiFe₂O₄纳米复合材料通过跨距80进行了改性，并通过固体研磨（SG）分散在冷冻机油中。此外，使用四球摩擦测试仪研究了纳米复合材料的摩擦学性能。结果表明，当富勒烯纳米复合材料的质量浓度高于60 ppm并且纳米油的浓度为2 g / L时，摩擦系数从0.13降低至0.06，这意味着磨损减少。 在空调测试条件下，压缩机的性能系数可以提高1.23％。

对于采用碟式斯特林技术的太阳能系统有多种分析方法。 这些分析之一是有限时间热力学分析，可通过计算过程时间来获得系统的总功率。在这项研究中，已经考虑了来自集热器表面的对流和辐射传热损失，冷热缸之间的传导传热以及冷侧热交换器。在此调查过程中，同时优化了四个目标函数，包括功率，效率，熵和经济因素。除了四目标优化之外，还对碟式斯特林模型进行了三目标，两目标和单目标优化。具有后表达偏好的多目标粒子群算法（MOPSO）用于多目标优化，而具有预表达偏好的分支定界算法用于单目标和多目标优化。在具有偏好的后表达的多目标优化的情况下，获得Pareto最优前沿，然后通过实施模糊，LINMAP和TOPSIS决策算法，可以获得单个最优结果。结果表明，MOPSO可以优化碟式斯特林有限时间热力学方程。