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1.
《International Journal of Hydrogen Energy》2022,47(90):38198-38218
Generally, white-flowering horse-chestnut seed (WFHC) found in roadsides, parks and gardens, which spills around and causes environmental pollution, is defined as waste-bio material. This study is quite remarkable as it gives WFHC a new field of usage and literally prioritizes the environment. Here, waste-bio WFHC was tested as supporter for tri-metallic RuNiPd nanoclusters in the eco-friendly dehydrogenation of dimethylamine-borane (DMAB). Core-shell-looking tri-metallic RuNiPd@WFHC, with 264.09 ± 45.55 nm particle size, were in-situ synthesized throughout dehydrogenation of DMAB at 35.0 ± 0.1 °C. The WFHC and tri-metallic Ru2.00Ni1.86Pd1.00@WFHC NCs were characterized by advanced analysis and their surface morphologies were studied in detail using adsorption models. The N2 adsorption-desorption and logarithmic-Freundlich plots indicated that surface morphologies have heterogeneous multi-layer and typical Type-III isotherm with mesoporous surfaces. Also, detailed kinetic studies were actualized on the dehydrogenation of DMAB catalyzed by tri-metallic Ru2.00Ni1.86Pd1.00@WFHC NCs with 158 h?1 TOF value. 相似文献
2.
随着交通的日益发展,大跨度跨线连续刚构桥梁修建越来越多。本文结合潼湖特大桥跨潮莞高速(88+160+88)m连续刚构施工的成功实践,详细阐述了该桥的施工关键及其梁体施工的线型控制,跨既有公路施工防护及混凝土施工等关键施工技术,可供类似工程参考。 相似文献
3.
Lightweight ciphers are increasingly employed in cryptography because of the high demand for secure data transmission in wireless sensor network, embedded devices, and Internet of Things. The PRESENT algorithm as an ultra-lightweight block cipher provides better solution for secure hardware cryptography with low power consumption and minimum resource. This study generates the key using key rotation and substitution method, which contains key rotation, key switching, and binary-coded decimal-based key generation used in image encryption. The key rotation and substitution-based PRESENT architecture is proposed to increase security level for data stream and randomness in cipher through providing high resistance to attacks. Lookup table is used to design the key scheduling module, thus reducing the area of architecture. Field-programmable gate array (FPGA) performances are evaluated for the proposed and conventional methods. In Virtex 6 device, the proposed key rotation and substitution PRESENT architecture occupied 72 lookup tables, 65 flip flops, and 35 slices which are comparably less to the existing architecture. 相似文献
4.
Catalysts of quaternary composition have been prepared and tested for the Sabatier process. For catalyst syntheses the following techniques have been used: sol‐gel methods, wet impregnation and incipient wetness impregnation. The Sabatier reaction was carried out at temperatures between 520 K and 670 K, pressures of 15 bar and 30 bar using a mixture H2:CO2 of 4:1. Activity screening of the microscale wall catalysts was performed by a custom‐built 10‐fold parallel gas‐flow microreactor setup in sequential operating mode. To analyze the gas phase compositions GC‐FID was used. 相似文献
5.
《International Journal of Hydrogen Energy》2022,47(29):13990-14007
Hydrogen can be produced via many different technologies; however, from a safety standpoint there exists no framework for selecting the right technology. Here, we provide a structured framework for assessment of the most desirable hydrogen production technology based on efficiency, safety, and infrastructure, by using a Multi-Criteria Decision-Making (MCDM) integrated Analytic Hierarchy Process (AHP) and life-cycle index (LInX) approach. We apply this modified MCDM approach to steam methane reforming (SMR), autothermal reforming, partial oxidation, alkaline electrolysis, polymer electrode membrane electrolysis, and solid oxide electrolyzer cell processes. Our results show that SMR is the most desirable technology based on the efficiency, safety, and infrastructure criteria. We employ fuzzy set theory to address subjectivity and uncertainty challenges in the data and found that although the technologies based on electrolysis have an environmental advantage, they exhibit higher uncertainties than non-renewable technologies such as SMR. Overall, this new framework addresses the challenge to find the most desirable and safer technology for hydrogen production. 相似文献
6.
无证书签名具有基于身份密码体制和传统公钥密码体制的优点,可解决复杂的公钥证书管理和密钥托管问题.Wu和Jing提出了一种强不可伪造的无证书签名方案,其安全性不依赖于理想的随机预言机.针对该方案的安全性,提出了两类伪造攻击.分析结果表明,该方案无法实现强不可伪造性,并在"malicious-but-passive"的密钥生成中心攻击下也是不安全的.为了提升该方案的安全性,设计了一个改进的无证书签名方案.在标准模型中证明了改进的方案对于适应性选择消息攻击是强不可伪造的,还能抵抗恶意的密钥生成中心攻击.此外,改进的方案具有较低的计算开销和较短的私钥长度,可应用于区块链、车联网、无线体域网等领域. 相似文献
7.
As the development of cloud computing and the convenience of wireless sensor netowrks, smart devices are widely used in daily life, but the security issues of the smart devices have not been well resolved. In this paper, we present a new NTRU-type public-key cryptosystem over the binary field. Specifically, the security of our scheme relies on the computational intractability of an unbalanced sparse polynomial ratio problem (DUSPR). Through theoretical analysis, we prove the correctness of our proposed cryptosystem. Furthermore, we implement our scheme using the NTL library, and conduct a group of experiments to evaluate the capabilities and consuming time of encryption and decryption. Our experiments result demonstrates that the NTRU-type public-key cryptosystem over the binary field is relatively practical and effective. 相似文献
8.
《International Journal of Hydrogen Energy》2019,44(35):19067-19079
In order to maximise European, national and regional research and innovation potential the European Union is investing in these fields through different funding mechanisms such as the ESIF or H2020 programme. This investment plan is part of the European 2020 strategy, where the concept of Smart Specialisation is also included.Smart Specialisation is an innovation policy concept designed to promote the efficient and effective use of public investment in regional innovation in order to achieve economic growth. The Smart Specialisation Platform was created to support this concept by assisting regions and Member States in developing, implementing and reviewing their research and innovation Smart Specialisation strategies.The Smart Specialisation Platform comprises several thematic platforms. The thematic Smart Specialisation Platform on energy (S3PEnergy) is a joint initiative of three European Commission services: DG REGIO, DG ENER, and the Joint Research Centre (JRC). The main objective of the S3PEnergy is to support the optimal and effective uptake of the Cohesion Policy funds for energy, and to better align energy innovation activities at national, local and regional level through the identification of the technologies and innovative solutions that support in the most cost-effective way the EU energy policy priorities.In the particular case of hydrogen technologies, the activities of the platform are mainly focused on supporting the new Fuel Cells and Hydrogen Joint Undertaking (FCH JU) initiative involving regions and cities. To date, more than 80 European cities and regions have committed to participate in this initiative through the signature of a Memorandum of Understanding, and more participants are expected to join. S3PEnergy is helping in the identification of potential combination of H2020 funding (provided through FCH JU) and ESIF.To identify potential synergies among these two funding sources, a mapping of the different ESIF opportunities has been performed. In order to map these opportunities, Operational Programmes (OPs) and research and innovation strategies for Smart Specialisation (RIS3) of the different European regions and Member States were analysed. The results of this mapping and analysis are presented in this paper. 相似文献
9.
考虑到不同句子对判断文档情感倾向的重要程度不同,因而区分文档的关键句和细节句将有助于提高情感分类的性能。同时,考虑到Title和上下文信息,提出了一种基于Title和加权TextRank抽取关键句的情感分析方法SKTT,实现了高效的情感分析。根据文档Title的情感权重计算Title贡献度,考虑到标点和语义规则对情感倾向的影响;根据加权TextRank算法思想,在文档正文中构建了一个情感句有向图来提取关键句;计算所有关键句的情感倾向进行情感分类。在4个领域上进行实验,实验结果表明,该SKTT方法性能明显优于Baseline,具有高效性。 相似文献
10.
筛选出适合制备硬质道路石油沥青关键组分的减压渣油,并以此为原料,考察了蒸馏深拔、深度氧化及溶剂脱沥青工艺制备的硬质道路沥青关键组分的性能。所制备的关键组分能够大幅提升基质沥青的高温性能,且通用性好;将关键组分与基质沥青按适合比例调合可以稳定生产高温性能好的硬质道路石油沥青,其混合料耐高温性能好。同时,为便于硬质沥青关键组分的使用,还开发了关键组分的造粒成型技术,提出其适于成型造粒的黏度范围为0.6~6 Pa?S。采用关键组分生产的硬质道路沥青用于高速公路实体工程,经过2年以上的气候和通车考验,沥青路面无车辙、无开裂,保持优良的使用性能。 相似文献