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石墨烯/钼基二硫族化合物范德华异质结光电探测器的研究进展

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新型炭材料（中英文） 2024年第3期39卷 439-457页

作者：张鑫华刘伟迪龚佑品刘庆丰陈志刚南京工业大学化工学院材料化学工程国家重点实验室江苏南京211816 School of Chemistry and Physics ARC Research Hub in Zero-emission Power Generation for Carbon Neutralityand Center for Materials ScienceQueensland University of TechnologyBrisbaneQLD 4000Australia 重庆大学物理学院前沿交叉学科研究院量子材料与器件研究中心重庆400044

石墨烯因其高载流子迁移率和宽光谱吸收范围而广泛应用于光电探测。然而,其低光吸收率导致的高暗电流严重限制了它的光电探测性能。钼基二硫族化合物(MoX_(2),X=S、Se和Te)具有高的吸收系数,能够弥补石墨烯基光电探测器中暗电流较高的劣... 详细信息

石墨烯因其高载流子迁移率和宽光谱吸收范围而广泛应用于光电探测。然而,其低光吸收率导致的高暗电流严重限制了它的光电探测性能。钼基二硫族化合物(MoX_(2),X=S、Se和Te)具有高的吸收系数,能够弥补石墨烯基光电探测器中暗电流较高的劣势,因此基于石墨烯/MoX_(2)范德华异质结的光电探测器能够表现出优异的光电子特性。本综述首先回顾了光电探测器的工作原理、性能指标和结构。之后,从材料基础的角度突出了石墨烯/MoX_(2)范德华异质结光电探测器的重要性。接着,总结了石墨烯/MoX_(2)范德华异质结光电探测器的制备方法和性能增强策略。最后,强调了这类异质结光电探测器当前面临的挑战及未来的发展方向。本综述将为这类高性能范德华异质结光电探测器的设计提供一定的指导和参考。

关键词：石墨烯钼基二硫族化合物异质结光电探测器范德华

Interaction effect of micro-and macro-organic on the biogeochemical function of the sediment and aquatic interface

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Journal of Environmental Sciences 2006年第3期18卷 468-474页

作者： XIAO Xiang LIAO Ling zhang xin-hua Guangzhou Environment Protection Bureau Guangzhou 510032 China Guangzhou Research Institute of Environmental Protection Guangzhou 510620 China South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China

Constructed stormwater infiltration basins have been broad applied in urban areas in terms of stormwater disposal and compensation of reduced groundwater recharge. However, stormwater derived from sediments accumulating in infiltration beds may act as a source of dissolved contaminants for groundwater. Concentrations of DO, NO3-N, NO2^--N, NH4^＋-N and PO4^3--P were monitored at multiple depth with time. The results showed that the occurrence of denitrificarion was restrained by sediments in term of no invertebrates. Under the conditions of invertebrates inoculated, the concentrations of DO, NO^3--N, NO2^＋-N, NH4^＋-N and PO4^3＋-P varied respectively with time and the occurrence of nitrification and mobilizing nitrate in the sediment. It is concluded that there exist the invertebrate activities such as building tubes and galleries and excreting faecal pellet which may increase water dispersion and enhance accessibility of nutrient, and stimulate microbial process effected in the sediment. Besides, the natural death and rot of worms were also found to be important factors of the invertebrate activities.

关键词： infiltration basins urban stormwater polluted sediments invertebrates effects

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与X型宽尾墩联合的台阶溢洪道消能特性研究

价值工程 2024年第28期43卷 113-116页

作者：杨钊杨川张鑫华杨凌职业技术学院杨凌712100

通过数值模拟对与X型宽尾墩联合的台阶溢洪道水流水力特性进行了研究,并结合不同工况下的水流流态、流速分布等水力要素,对溢洪道水流消能特性进行了探究。结果表明:单宽流量较小时,消能率与传统台阶溢洪道一致,可达60%至70%。当单宽流... 详细信息

通过数值模拟对与X型宽尾墩联合的台阶溢洪道水流水力特性进行了研究,并结合不同工况下的水流流态、流速分布等水力要素,对溢洪道水流消能特性进行了探究。结果表明:单宽流量较小时,消能率与传统台阶溢洪道一致,可达60%至70%。当单宽流量较大时,挑射水流占下泄水流主体,消能效果不明显,台阶中心线末端消能率不足25%,可能对台阶面造成破坏,宽度范围约为宽尾墩出口宽度的2/3。

关键词： X型宽尾墩台阶溢洪道数值模拟消能特性

Compute extremely low-frequency electromagnetic field exposure by 3-D impendance method

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 113-116页

作者： HAN Yu-nan LV Ying-hua zhang Hong-xin Beijing University of Posts and Telecommunications Beijing 100876 ChinaAerospace Science and Technology Group Beijng 100076 China

A 3-D impedance method has been introduced to compute the electric currents induced in a human body exposed to extremely low-frequency electromagnetic field. The 3-D impedance method has been deduced from Maxwell equations and is put into the computation and simulation effectively to the visible human body model, which has 196×114×626 cells and more than 40 types of tissues. As the result, two representative cases are investigated. One is exposure of the human body to 100 μT （1 000 mG）, the limit recommended by the International Commission on Non-Ionizing Radiation Protection for the public and the other one is the exposure of human body to 0.4 laT （4 mG）, the level at which a statistical link appears with a doubled risk of development of childhood leukaemia. The distribution of induced current density can be obtained and the maximum of induced current are found to be 16 mA/m^2 and 0.07 mA/m^2.

关键词： 3-D impedance method induced current magnetic flux density visible human body model extremely low frequency (ELF)

Influence of deflection angles on flow behaviours in openchannel bends

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Journal of Mountain Science 2018年第10期15卷 2292-2306页

作者： LI Bing-dong zhang xin-hua TANG Han-song TSUBAKI Ryota State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Department of Civil Engineering/City College City University of New York Department of Civil Engineering Nagoya University

The deflection angle of a river bend plays an important role on behaviours of the flow within it, and a clear understanding of the angle's influence is significant in both theoretical study and engineering application. This paper presents a systematic numerical investigation on effects of deflection angles(30°, 60°, 90°, 120°, 150°, and 180°) on flow phenomena and their evolution in open-channel bends using a Re-Normalization Group(RNG) κ-ε model and a volume of fluid(VOF) method. The numerical results indicate that the deflection angle is a key factor for flows in bends. It is shown that the maximum transverse slope of water surface occurs at the middle cross section of a bend, and it increases with the deflection angle. Besides a major vortex, or, the primary circulation cell near the channel bottom, a secondary vortex, or, an outer bank cell, may also appear above the former and near the outer bank when the deflection angle is sufficiently large, and it will gradually migrate towards the inner bank and evolve into an inner bank cell. The strength of the secondary circulations increases with the deflection angle. The simulation demonstrates that there is alow-stress zone on the bed near the outer bank and a high-stress zone on the bed near the inner bank, and both of them increase in size with the deflection angle. The maximum of shear stress on the inner bank increases nonlinearly with the angle, and its maximums on the outer bank and on the bed take place when the deflection angle becomes 120°.

关键词： Open channel Deflection angle Transverse slope of water surface Secondary flow Shear stress

Effect of Phopshate Fertilizer and Manure on Crop Yield, Soil P Accumulation, and the Environmental Risk Assessment

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Agricultural Sciences in China 2007年第9期6卷 1107-1114页

作者： LIU Jian-ling LIAO Wen-hua zhang Zuo-xin zhang Hai-tao WANG xin-jun MENG Na College of Resource and Environmental Sciences Agricultural University of Hebei Baoding 071001 P.R. China

Phosphorus （P） applied from fertilizer and manure is important in increasing crop yield and soil fertility; however, excessive uses of phosphate fertilizer and manure may also increase P loss from agricultural soils, posing environmental impact. A long term experiment was conducted on a calcareous soil （meadow cinnamon） in Hebei Province, China, from 2003 to 2006 to investigate the effects of phosphate fertilizer and manure on the yield of Chinese cabbage, soil P accumulation, P sorption saturation, soluble P in runoff water, and P leaching. P fertilizer （P2O5） application at a rate of 360 kg ha^-1 or manure of 150 t ha^-1 significantly increased Chinese cabbage yield as compared to the unfertilized control. However, no significant yield response was found with excessive phosphate or manure application. Soil Olsen-P, soluble P, bioavailable P, the degree of phosphorus sorption saturation in top soil layer （0-20 cm）, and soluble P in runoff water increased significantly with the increase of phosphate fertilizer and manure application rates, whereas the maximum phosphorus sorption capacity （Qm） decreased with the phosphate fertilizer and manure application rates. Soil Olsen-P and soluble P also increased significantly in the sub soil layer （20-40 cm） with the high P fertilizer and manure rates. It indicates that excessive P application over crop demand can lead to a high environmental risk owing to the enrichment of soil Olsen-P, soluble P, bioavailable P, and the degree of phosphorus sorption saturation in agricultural soils.

关键词： phosphate fertilizer manure yield response P accumulation in soil environmental risk of P loss

Exotic Homoclinic Surface of a Saddle-Node Limit Cycle in a Leech Neuron Model

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Chinese Physics Letters 2011年第3期28卷 24-27页

作者： YOOER Chi-Feng WEI Fang XU Jian-Xue zhang xin-hua Institute of Neuroscience Fourth Military Medical UniversityXi’an 710032 Institute of Nonlinear Dynamics Xi’an Jiaotong UniversityXi’an 710049 XAC Research and Development Center Xi’an 710089

We carry out numerical and theoretical investigations on the global unstable invariant set(manifold)of a saddlenode limit cycle in a leech heart interneuron *** corresponding global bifurcation is accompanied by an explosion of secondary bifurcations of limit cycles and the emergence of loop-shaped bifurcation *** dynamical behaviors of the trajectories of the invariant set are very complicated and can only be partially explained by existing theories.

关键词： invariant bifurcation limit

SAW chirp Fourier transform for MB-OFDM UWB receiver

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The Journal of China Universities of Posts and Telecommunications 2006年第3期13卷 1-4页

作者： HE Peng-fei LUE Ying-hua zhang Hong-xin WANG Ye-qiu XU Yong Institute of Telecommunication and Network Technology Beijing University of Posts and Telecommunications Beijing 100876 China

In the conventional multiband orthogonal frequency division multiplexing ultra wideband （MB-OFDM UWB ） receiver, the fast Fourier transform （FFT） algorithm is realized by the expensive and power-consuming digital signal processor （DSP） chips. In this article, the lower power, lower cost, and lower complexity real-time analog surface acoustic wave （SAW） chirp Fourier transform devices were used to replace the DSP part. A MB-OFDM UWB receiver based on the M-C-M SAW chirp Fourier transform was presented, and the step of signal transformation from input signals was also depicted. The simulation results show that the proposed receiver provides similar bit error performance compared to the fully digital receiver when used in the channel environments proposed by the IEEE 802.15SG3a.

关键词： MB-OFDM UWB SAW chirp Fourier transform

Regulation of Ti(C,N)deposition on hot surface of refractory in blast furnace hearth

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Journal of Iron and Steel Research International 2024年第6期31卷 1423-1435页

作者： Jian Cao Cui Wang Jjan-liang zhang Ke-xin Jiao Guo-hua zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

Ti(C,N)concentration was found to be lower on the hearth sidewall of a blast furnace and increased gradually toward the bottom of the blast *** Ti(C,N)protective layer in a blast furnace is ***,the formation of a Ti(C,N)protective layer was promoted by studying the heterogeneous nucleation principle of titanium compounds on different substances and regulation measures for the deposition process of titanium compounds on refractories or *** lattice disregistry between the titanium compounds and the main components in the refractory or the main impurities in the protective layer was calculated using a two-dimensional disregistry equation to study the heterogeneous nucleation principle of titanium *** results revealed that in refractory materials,the heterogeneous nucleation of carbonitride is weak when C,SiO_(2),and Al_(2)O_(3) are used as heterogeneous nucleation substrates,and the heterogeneous nucleation of carbonitride is strong when TiO_(2) and SiC are used as heterogeneous nucleation *** nucleation phases,TiC,TiN,Ti(C_(0.3),N_(0.7)),and Ti(C_(0.5),N_(0.5))have similar heterogeneous nucleation ability in single component refractory,and the type of carbonitride has little effect on the lattice *** impurities in the protective layer as the substrate phases are not conducive to the heterogeneous nucleation of *** CaS was used as the substrate phase,the heterogeneous nucleation ability of carbonitride was the *** carbon and alumina were not conducive to the heterogeneous nucleation of carbonitride,but carbon was more unfavourable than alumina.

关键词： Ti(C,N) Lattice disregistry Lattice constant Heterogeneous nucleation Regulation measure