检索结果-南通市图书馆

New steelmaking process based on clean deoxidation technology

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1249-1262页

作者： Zhongliang Wang Yanping Bao State Key laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

After the converter steelmaking process,a considerable number of ferroalloys are needed to remove dissolved oxygen from the molten steel,but it also forms a lot of oxide inclusions that cannot be completely removed.At the same time,it increases the carbon emis-sions in the steel production process.After years of research,our team have developed a series of clean deoxidation technologies,includ-ing carbon deoxidation,hydrogen deoxidation,and waste plastic deoxidation of molten steel to address the aforementioned issues.In this study,thermodynamic calculations and laboratory experiments were employed to verify that carbon and hydrogen can reduce the total oxygen content in the molten steel melt to below 5×10^(-6) and 10×10^(-6),respectively.An analysis of the deoxidation mechanisms and ef-fects of polyethylene and polypropylene was also conducted.In addition,the applications of carbon deoxidation technology in different steels with the hot-state experiment and industrial production were discussed carefully.The carbon deoxidation experimental results of different steels were as follows:(1)the oxygen content of bearing steel was effectively controlled at 6.3×10^(-6) and the inclusion number density was lowered by 74.73%compared to aluminum deoxidized bearing steel;(2)the oxygen content in gear steel was reduced to 7.7×10^(-6) and a 54.49%reduction of inclusion number density was achieved with almost no inclusions larger than 5μm from the average level of industry gear steels;(3)a total oxygen content of M2 high-speed steel was as low as 3.7×10^(-6).In industrial production practice,car-bon deoxidation technique was applied in the final deoxidation stage for non-aluminum deoxidized bearing steel,and it yielded excellent results that the oxygen content was reduced to below 8×10^(-6) and the oxide inclusions in the steel mainly consist of silicates,along with small amounts of spinel and calcium aluminate.

关键词： clean deoxidation carbon deoxidation hydrogen deoxidation waste plastics deoxidation

A review on current development of thermophotovoltaic technology in heat recovery

在线全文

学校读者我要写书评

暂无评论

International Journal of Extreme Manufacturing 2024年第2期6卷 297-323页

作者： Shuni Chen Yanming Guo Qinghui Pan Yong Shuai Ministry of Industry and Information technology Key laboratory of Aerospace Thermophysics School of Energy Science and EngineeringHarbin Institute of TechnologyHarbin 150001People’s Republic of China

The burning of fossil fuels in industry results in significant carbon emissions,and the heat generated is often not fully utilized.For high-temperature industries,thermophotovoltaics(TPVs)is an effective method for waste heat recovery.This review covers two aspects of high-efficiency TPV systems and industrial waste heat applications.At the system level,representative results of TPV complete the systems,while selective emitters and photovoltaic cells in the last decade are compiled.The key points of components to improve the energy conversion efficiency are further analyzed,and the related micro/nano-fabrication methods are introduced.At the application level,the feasibility of TPV applications in high-temperature industries is shown from the world waste heat utilization situation.The potential of TPV in waste heat recovery and carbon neutrality is illustrated with the steel industry as an example.

关键词： thermophotovoltaic waste heat recovery micro/nano-fabrication carbon neutrality

High temperature treatment induced production of unreduced 2n pollen in Camellia oleifera

在线全文

学校读者我要写书评

暂无评论

Horticultural Plant Journal 2024年第3期10卷 879-896页

作者： Hongda Deng Xiaoyu Zhang Song Sheng Yuxun Huang Ziqi Ye Tongyue Zhang Xing Liu Zhiqiang Han The laboratory of forestry Genetics Central South University of Forestry and TechnologyChangshaHunan 410004China Yuelushan laboratory ChangshaHunan 410128China Key laboratory of Cultivation and Protection for Non-Wood forest Trees of Ministry of Education Central South University of Forestry and TechnologyChangshaHunan 410004China National forest and Seedling Workstation of Hunan Province The Forestry Department of Hunan ProvinceChangshaHunan 410004China

Unreduced gametes through chromosome doubling play a major role in the process of plant polyploidization.Our previous work confirmed that Camellia oleifera can produce natural 2n pollen,and it is possible to induce the 2n pollen formation by high temperature treatment.This study focused on the optimization of the 2n pollen induction technique and the mechanisms of high temperature-induced2n pollen formation in C.oleifera.We found that the optimal protocol for inducing 2n pollen via high temperature was to perform 45℃with4 h at the prophaseⅠstage of the pollen mother cells(PMCs).Meanwhile,high temperature significantly decreased the yield and fertility of2n pollen.Through the observation of meiosis,abnormal chromosome and cytological behaviour was discovered under high-temperature treatment,and we confirmed that the formation of 2n pollen is caused by abnormal cell plate.Based on weighted gene co-expression network analysis,fifteen hub genes related to cell cycle control were identified.After male flower buds were exposed to heat shock,polygalacturonase gene(CoPGX3)was significantly upregulated.We inferred that high temperature causes the CoPGX3 gene to be overexpressed and that CoPGX3 is redistributed into the cytosol where it degrades cytoplasmic pectin,which leads to an abnormal cell plate.Furthermore,abnormal cytokinesis resulted in the formation of dyads and triads,and PMCs divided to produce 2n pollen.Our findings provide new insights into the mechanism of 2n pollen induced by high temperature in a woody plant and lay a foundation for further ploidy breeding of C.oleifera.

关键词： Camellia oleifera Pollen mother cells(PMCs) High temperature Meiosis 2n pollen CoPGX3

Selective photosynthesis of imines from biomass-derived aldehydes over Ni/TiO_(2)

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第3期43卷 1116-1124页

作者： Wu-Lin Li Qing-Qing Zhang Lin Dong Wen-Jun Zhang Li-Li Lin Zu-Peng Chen Jiangsu Co-Innovation Center of Efficient Processing and Utilization of forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing210037China Institute of Industrial Catalysis State Key Laboratory of Green Chemistry Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

Photocatalytic reductive amination of biomass-derived aldehydes is a desirable way to selectively upgrade biomass into value-added nitrogen-containing chemicals under mild conditions.However,it is challenging to produce imines in high selectivity because of the undesirable side reactions caused by the activity of functional groups.Here,we demonstrate the highly reactive and selective production of imines from biomass derived aldehydes via the photocatalytic reductive amination,using a defective TiO_(2)supported nickel catalyst.The employment of methanol as the hydrogen donor and ammonia solution as the nitrogen source avoids the use of high-pressure H_(2)and expensive amines,rendering the current catalytic process safe,economical,and environmentally friendly.In depth investigations attribute the improved separation and transfer of photogenerated charge carriers to the presence of oxygen vacancies and decorated Ni nanoparticles,thereby accelerating the production of imines from benzaldehyde amination(conversion,95.8%;seleetivity,95.2%).Furthermore,the developed system could be easily translated to the photocatalytic conversions of various biomass derived aldehydes,which provided an example of a cost-effective and sustainable approach for the valorization of biomass derived feedstocks.

关键词： Photocatalysis Biomass derivatives Imines Reduction amination Heterogeneous catalyst

Adaptive learning-based optimal tracking control system design and analysis of a disturbed nonlinear hypersonic vehicle model

在线全文

学校读者我要写书评

暂无评论

Science China Technological Sciences 2024年第6期67卷 1893-1906页

作者： AN Kai WANG ZhenGuo HUANG Wei National University of Defense technology Hypersonic technology laboratory

We propose an adaptive learning-based optimal control scheme for height-velocity control models considering model uncertainties and external disturbances of hypersonic winged-cone vehicles. The longitudinal nonlinear model is first established and transformed into the control-oriented error equations, and the control scheme is organized by a steady-compensation combination. To overcome and eliminate the impact of model uncertainties and external disturbances, an adaptive radial basis function neural network(RBFNN) is designed by a q-gradient approach. Taking the height-velocity error system with estimated uncertainties into account, the adaptive learning-based optimal tracking control(ALOTC) scheme is proposed by combining the critic-only adaptive dynamic programming(ADP) framework and parameter optimization of system settling time. Furthermore,a novel weight update law is proposed to satisfy the online iteration requirements, and the algorithm convergence and closedloop stability are discussed by the Lyapunov theory. Finally, four simulation cases are provided to prove the effectiveness,accuracy, and robustness of the proposed scheme for the hypersonic longitudinal control system.

关键词： optimal tracking control adaptive dynamic programming RBFNN hypersonic vehicle

For Mega-Constellations: Edge Computing and Safety Management Based on Blockchain technology

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

China Communications 2024年第2期21卷 59-73页

作者： Zhen Zhang Bing Guo Chengjie Li College of Computer Science Sichuan UniversityChengdu 610064China The Key laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and TechnologySouthwest Minzu UniversityChengdu 610225China National Key laboratory of Science and technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China

In mega-constellation Communication Systems, efficient routing algorithms and data transmission technologies are employed to ensure fast and reliable data transfer. However, the limited computational resources of satellites necessitate the use of edge computing to enhance secure communication.While edge computing reduces the burden on cloud computing, it introduces security and reliability challenges in open satellite communication channels. To address these challenges, we propose a blockchain architecture specifically designed for edge computing in mega-constellation communication systems. This architecture narrows down the consensus scope of the blockchain to meet the requirements of edge computing while ensuring comprehensive log storage across the network. Additionally, we introduce a reputation management mechanism for nodes within the blockchain, evaluating their trustworthiness, workload, and efficiency. Nodes with higher reputation scores are selected to participate in tasks and are appropriately incentivized. Simulation results demonstrate that our approach achieves a task result reliability of 95% while improving computational speed.

关键词： blockchain consensus mechanism edge computing mega-constellation reputation management

For LEO Satellite Networks: Intelligent Interference Sensing and Signal Reconstruction Based on Blind Separation technology

在线全文

学校读者我要写书评

暂无评论

China Communications 2024年第2期21卷 85-95页

作者： Chengjie Li Lidong Zhu Zhen Zhang The Key laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and Technology(Southwest Minzu University)Chengdu 610000China National Key laboratory of Science and technology on Communications(University of Electronic Science and technology of China) Chengdu 610000China College of Computer Science(Sichuan University) Chengdu 610000China

In LEO satellite communication networks,the number of satellites has increased sharply, the relative velocity of satellites is very fast, then electronic signal aliasing occurs from time to time. Those aliasing signals make the receiving ability of the signal receiver worse, the signal processing ability weaker,and the anti-interference ability of the communication system lower. Aiming at the above problems, to save communication resources and improve communication efficiency, and considering the irregularity of interference signals, the underdetermined blind separation technology can effectively deal with the problem of interference sensing and signal reconstruction in this scenario. In order to improve the stability of source signal separation and the security of information transmission, a greedy optimization algorithm can be executed. At the same time, to improve network information transmission efficiency and prevent algorithms from getting trapped in local optima, delete low-energy points during each iteration process. Ultimately, simulation experiments validate that the algorithm presented in this paper enhances both the transmission efficiency of the network transmission system and the security of the communication system, achieving the process of interference sensing and signal reconstruction in the LEO satellite communication system.

关键词： blind source separation greedy optimization algorithm interference sensing LEO satellite communication networks signal reconstruction

Odorant-binding protein 19 in Monochamus alternatus involved in the recognition of a volatile strongly emitted from ovipositing host pines

在线全文

学校读者我要写书评

暂无评论

Insect Science 2024年第1期31卷 134-146页

作者： Ruinan Yang Dongzhen Li Shancheng Yi Yi Wei Manqun Wang Hubei Insect Resources Utilization and Sustainable Pest Management Key laboratory College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina Key laboratory of forest Protection of National forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijingChina

Monochamus alternatus is the primary carrier of pine wood nematodes,which pose a serious threat to Pinus spp.in many countries.Newly emerging M.alternatus adults feed on heathy host pines,while matured adults transfer to stressed host pines for mating and oviposition.Several odorant-binding proteins(OBPs)of M.alternatus have been proved to aid in the complex process of host location.To clarify the corresponding relations between OBPs and pine volatiles,more OBPs need to be studied.In this research,MaltOBP19 showed a specific expression in the antennae and mouthparts of M.alternatus,and it was marked in 4 types of antenna sensilla by immunolocalization.Fluorescence binding assays demonstrated the high binding affinity of MaltOBP19 with camphene and myrcene in vitro.In Y-tube olfactory experiments,M.alternatus adults were attracted by camphene and RNAi of OBP19 via microinjection significantly decreased their attraction index.Myrcene induced phobotaxis,but RNAi had no significant effect on this behavior.Further,we found that ingesting dsOBP19 produced by a bacteria-expressed system with a newly constructed vector could lead to the knockdown of MaltOBP19.These results suggest that MaltOBP19 may play a role in the process of host conversion via the recognition of camphene,which has been identified to be strongly released in stressed host pines.In addition,it is proved that knockdown of OBP can be achieved by oral administration of bacteria-expressed double-stranded RNA in M.alternatus adults,providing a new perspective in the control of M.alternatus.

关键词： bacteria-expressed dsRNA camphene Japanese pine sawyer beetle MaltOBP19 RNAi stressed host pines

Biomass-based materials for advanced supercapacitor:principles,progress,and perspectives

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Aggregate

Aggregate 2024年第1期5卷 95-114页

作者： Yaxuan Wang Ting Xu Kun Liu Meng Zhang Xu-Min Cai Chuanling Si State Key laboratory of Biobased Fiber Manufacturing technology Tianjin Key Laboratory of Pulp and PaperTianjin University of Science and TechnologyTianjinChina Jiangsu Co-Innovation Center of Efficient Processing and Utilization of forest Resources College of Chemical EngineeringNanjing Forestry UniversityNanjingChina

Supercapacitors exhibit considerable potential as energy storage devices due to their high power density,fast charging and discharging abilities,long cycle life,and ecofriendliness.With the increasing environmental concerns associated with synthetic compounds,the use of environment friendly biopolymers to replace conventional petroleum-based materials has been widely studied.Biomass-based materials are biodegradable,renewable,environment friendly and non-toxic.The unique hierarchical nanostructure,excellent mechanical properties and hydrophilicity allow them to be used to create functional conductive materials with precisely controlled structures and different properties.In this review,the latest development of biomass-based supercapacitor materials is reviewed and discussed.This paper describes the physical and chemical properties of various biopolymers and their impact on supercapacitors,as well as the classification and basic principles of supercapacitors.Then,a comprehensive discussion is presented on the utilization of biomass-based materials in supercapacitors and their recent applications across a range of supercapacitor devices.Finally,an overview of the future prospects and challenges pertaining to the utilization of biomass-based materials in supercapacitors is provided.

关键词： biomass electrodes electrolyte energy storage supercapacitor