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Insights into heat management of hydrogen adsorption for improved hydrogen isotope separation of porous materials

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Journal of Materials Science & Technology 2021年第17期76卷 200-206页

作者： Nan Sun Pei-long Li Ming Wen Jiang-Feng Song Zhi zhang Wen-Bin Yang Yuan-Lin Zhou De-Li Luo Quan-Ping zhang State Key Laboratory of Environment-friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang 621010China Institute of Materials China Academy of Engineering PhysicsJiangyou 621908China

Separating high-purity hydrogen isotopes from their mixture still remains a huge challenge due to almost the identical physicochemical *** importance has been attached to tune microstructure of porous materials,while heat management during hydrogen isotope separation tends to be ***,a porous material 5 A molecular sieve(5 A)is mixed with graphene(GE)under ball grinding to enhance its thermal conductivity for hydrogen isotope *** thermal conductivity increases from 0.19 W m^(-1)K^(-1)of neat 5 A,0.75 W m^(-1)K^(-1)of 5 A/GE2(2 wt%GE)to 1.23 W m^(-1)K^(-1)of 5 A/*** addition,introducing GE into 5 A promotes hydrogen adsorption and D_(2)/H_(2)adsorption ratio.5 A/GE2 shows the highest D_(2)adsorption capacity(5.40 mmol/g)and the largest D_(2)/H_(2)adsorption ratio(1.07)among the *** also displays a high efficiency of heat transfer that contributes to a low energy consumption due to the shortened cycle time during hydrogen isotope *** work offers new insights into material design for improved hydrogen isotope separation,which is greatly crucial to scientific and industrial applications,such as fuel self-sustaining in fusion reactors.

关键词： Hydrogen isotope separation Hydrogen adsorption Thermal conductivity Porous material Graphene

Enhanced Thermoelectric Performance of Non-equilibrium Synthesized Fe0.4Co3.6Sb12-xGex Skutterudites via Randomly Distributed Multi-scaled Impurity Dots

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Journal of Wuhan University of Technology(Materials Science) 2018年第4期33卷 772-777页

作者：章嵩 HU Xuan 杨梅君 cheng Hong TU Rong zhang Lianmeng State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China The Center for Materials Research and Analysis Wuhan University of TechnologyWuhan 430070China

The p-type Ge doped Fe0.4Co3.6Sb12-xGex skutterudites with multi-scaled impurity dots（500 nm-2 mm） were successfully prepared by using melt-quenching（MQ） and subsequent spark plasma sintering（SPS） technique. Compared with traditional method, the new technology significantly shortened the processing time from several days to less than 24 hours. The phase of impurity dots was demonstrated to be CoSb through analysis of X-ray diffraction（XRD） and energy-dispersive spectrum（EDS）. Impurity dots were induced by Ge substitution of Sb in the non-equilibrium synthesized process. Due to the abandonment of the long reaction of annealing crystallization, a few of Ge atoms would fail to substitute Sb site of skutterudite in this non-equilibrium synthesized process, leading to that the multi-scaled impurity dots randomly distributed in the matrix of skutterudite Fe0.4Co3.6Sb12-xGex. The combination of multi-scaled impurity dots scattering long wavelength heat-carrying phonons and the point defect scattering short and middle wavelength heat-carrying phonons dramatically made the 22.2% reduction of lattice thermal conductivity. As a result, compared with unsubstituted sample of Fe0.4Co3.6Sb12, the maximum ZT value was increased by 30.5%. Thus, the two marked features of this new synthesis process, the shortened preparation time and the enhanced thermoelectric performance, would make a promising commercial application in the future.

关键词： multi-scaled impurity dots Sb site substitution p-type thermoelectric transport properties

A Heterogeneous Information Fusion Deep Reinforcement Learning for Intelligent Frequency Selection of HF Communication

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China Communications 2018年第9期15卷 73-84页

作者： Xin Liu Yuhua Xu Yunpeng cheng Yangyang Li Lei Zhao Xiaobo zhang Guangxi key Laboratory Fund of Embedded Technology and Intelligent System Guilin University of Technology College of Communication Engineering Army Engineering University of PLA

The high-frequency(HF) communication is one of essential communication methods for military and emergency application. However, the selection of communication frequency channel is always a difficult problem as the crowded spectrum, the time-varying channels, and the malicious intelligent jamming. The existing frequency hopping, automatic link establishment and some new anti-jamming technologies can not completely solve the above problems. In this article, we adopt deep reinforcement learning to solve this intractable challenge. First, the combination of the spectrum state and the channel gain state is defined as the complex environmental state, and the Markov characteristic of defined state is analyzed and proved. Then, considering that the spectrum state and channel gain state are heterogeneous information, a new deep Q network(DQN) framework is designed, which contains multiple sub-networks to process different kinds of information. Finally, aiming to improve the learning speed and efficiency, the optimization targets of corresponding sub-networks are reasonably designed, and a heterogeneous information fusion deep reinforcement learning(HIF-DRL) algorithm is designed for the specific frequency selection. Simulation results show that the proposed algorithm performs well in channel prediction, jamming avoidance and frequency channel selection.

关键词： HF communication anti-jamming intelligent frequency selection markov decision process deep reinforcement learning

Relationship between RGS5 expression and differentiation and angiogenesis of gastric carcinoma

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World Journal of Gastroenterology 2010年第44期16卷 5642-5646页

作者： Jing-Hua Wang Wei-Sun Huang cheng-Ru Hu Xiao-Xiang Guan long-Bang Chen Hang-Bo Zhou Department of Pathology Nanjing General Hospital of Nanjing Military CommandMedica l School of Nanjing UniversityNanjing 210002Jiangsu ProvinceChina

AIM:To explore the regulator of G-protein signaling 5 (RGS5) expression in gastric carcinoma and its association with differentiation and microvascular density (MVD).METHODS:Expression of RGS5 and CD34 were examined in 76 cases of gastric carcinoma,including 22 cases with lymph node metastasis and 54 cases without lymph node metastasis determined by immunohistochemistry (IHC).MVD was assessed using CD34 monoclonal *** presence of RGS5 and CD34 was analyzed by IHC using the Envision ***:The RGS5 expression in gastric carcinoma was positively correlated with the differentiation of the tumor (r=0.345,P 0.05).The average MVD in the group with lymph node metastasis was significantly higher than that in the group without lymph node metastasis (P < 0.05).RGS5 expression was negatively correlated with the average MVD (P < 0.05).CONCLUSION:RGS5 expression level in gastric carcinoma is associated with the differentiation and MVD of the tumor,and may be used as an important parameter for determining the prognosis of gastric carcinoma patients.

关键词： RGS5 expression Gastric carcinoma Differentiation Microvascular density

Physiological and Biochemical Responses of Perennial Ryegrass Mixed Planting with Legumes under Heavy Metal Pollution

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1749-1765页

作者： Yi Xi Li zhang Yanhong Xu Wei cheng Chao Chen College of Animal Science Guizhou UniversityGuiyang550025China

In artiﬁcially controlled pot experiments,perennial ryegrass was mixed with other leguminous plants(white clo-ver and alfalfa)and treated with lead,zinc and cadmium(337 mg·kg^(-1),648 mg·kg^(-1),and 9 mg·kg^(-1),respectively)to simulate compound pollution *** results showed that the concentrations of heavy metals,trans-port factors,and bioconcentration factors in mixed planting of ryegrass decreased compared with those in *** of whether heavy metal pollution was introduced,mixed planting increased the aboveground and underground biomasses of *** different mixed planting treatments had no signiﬁcant impact on the chlorophyll concentration of *** mowing time,mixed planting treatment,and heavy metal treatment had impacts on antioxidant and osmotic adjustment substances,and there were some *** mixed planting treatment did not signiﬁcantly affect glutathione concentration,cysteine concentration,or nonprotein *** planting generally increased the nitrogen and phosphorus concentrations of ryegrass while reducing the stoichiometric ratio of carbon,nitrogen,and *** results suggest that the mixed planting of ryegrass with legumes promotes the growth of ryegrass in the presence of high concentrations of heavy metal ***,it does not enhance the ability of ryegrass to remediate heavy metal pollution in the soil.

关键词： Perennial ryegrass mixed planting phytoremediation lead zinc and cadmium soil pollution

Porous LiFePO_(4)/NiP Composite Nanospheres as the Cathode Materials in Rechargeable Lithium Ion Batteries

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Nano Research 2008年第3期1卷 242-248页

作者： Chunsheng Li Shaoyan zhang Fangyi cheng Weiqiang Ji Jun Chen Institute of New Energy Material Chemistry Key Laboratory of Energy Material Chemistry(Tianjin)and Engineering Research Center of High-Energy Storage and Conversion(Ministry of Education)Nankai UniversityTianjin 300071China

We report the synthesis of porous LiFePO4/NiP composite nanospheres and their application in rechargeable lithium-ion batteries.A simple one-step spraying technique was developed to prepare LiFePO_(4)/NiP composite nanospheres with an electrical conductivity 10^(3)-10^(4) times that of bulk particles of LiFePO_(4).Electrochemical measurements show that LiFePO_(4) nanospheres with a uniform loading of 0.86 wt%1.50 wt%NiP exhibit high discharge capacity,good cycling reversibility,and low apparent activation *** superior electrode performance of the as-prepared composite nanospheres results from the greatly enhanced electrical conductivity and porous structure of the materials.

关键词： Nanospheres LiFePO_(4)/NiP spraying electrical conductivity rechargeable lithium-ion batteries

Routing protocol based on social characteristics for opportunistic networks

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The Journal of China Universities of Posts and Telecommunications 2014年第1期21卷 67-73,103页

作者： cheng Gang SONG Mei zhang Yong XING Yi-hai BAO Xu-yan School of Electronic Engineering Beijing University of Posts and Telecommunications Potevio Institute of Technology company Limited

Opportunistic networks are derived from delay tolerant networks, where mobile nodes have no end-to-end connections. Nodes are represented by people, which means that opportunistic networks can be regarded as social networks. Human mobility plays an important role in affecting the performance of forwarding protocols in social networks, furthermore, the trajectory of people＇s movements are driven by social characteristics. However, current routing protocols rely on simple mobility models, and rarely consider social characteristics. Considering two heterogeneous network models, an social opportunistic networks routing（SONR） was proposed which brings an adapted discrete Markov chain into nodes＇ mobility model and calculates the transition probability between successive status. Comparison was made between Spray, Wait and Epidemic protocol. Simulation show that SONR can improve performance on delivery ratio, delivery latency and network overhead, meanwhile. SONR approaches the performance of Epidemic routing.

关键词： opportunistic networks delay tolerant networks social characteristics Markov chain transition probability

Determination of the Circulation for a Large-Scale Wind Turbine Blade Using Computational Fluid Dynamics

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Fluid Dynamics & Materials Processing 2020年第4期16卷 685-698页

作者： Hao cheng Guangsheng Du Meng zhang Kun Wang Wenbin Bai School of Energy and Power Engineering Shandong UniversityJinan250061China

The determination of the circulation for wind turbine blades is an important problem in *** the present study,we develop a specific approach to evaluate the integral that represents mathematically the *** the potentialities of the method are assessed using a two-dimensional NACA64_A17 airfoil as a testbed and evaluating the influence of different integration paths and angles of attack on the circulation *** the method is applied to blades with different relative heights in order to provide useful reference data to be used for the optimization and reverse design of wind turbine *** shown by the results,the integral value changes with the integral path,and an“optimal circle radius”*** calibrate the integral value by comparing its value with the lift *** this was we succeed in showing that there is a certain error when the radius is too ***,the error can increase rapidly when the radius is too *** the radius of the circle is 1–6 times the chord length,the error of all integral values is less than 5%.The optimal radius varies with the angle of attack.

关键词： Airfoil lift wind turbine circulation distribution

Growth Kinetics of Proeutectoid Ferrite in an Fe-0.09C-1.5Mn-0.2Si Steel

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Journal of Iron and Steel Research International 2014年第10期21卷 964-968页

作者： Lin cheng Kai-ming WU Xiang-liang WAN Guo-hong zhang The State Key Laboratory of Refractories and Metallurgy Hubei Collaborative Innovation Center for Advanced SteelsInternational Research Institute for Steel TechnologyWuhan University of Science and Technology

Growth kinetics of proeutectoid ferrite, including grain boundary face nucleated ferrite, grain boundary edge nucleated ferrite allotriomorph and intragranular ferrite idiomorph, were experimentally measured in an Fe- 0.09C-1.5Mn-0.2Si steel and compared with theoretical calculation in local equilibrium and paraequilibrium modes. Grain boundary edge nucleated ferrite exhibited larger growth rate than grain boundary face nucleated ferrite and in- tragranular ferrite idiomorph. Experimental kinetics of proeutectoid ferrite was within the window defined by the lo- cal equilibrium and paraequilibrium limits. A transition of growth kinetics from paraequilibrium to local equilibrium was observed in the temperature range of 650--750 ℃, which can be explained in terms of solute drag.

关键词： steel proeutectoid ferrite kinetics solute drag