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Metasurface-assisted low-frequency performance enhancement of ultra-broadband honeycomb absorber based on carbon nanotubes

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Nano Research 2024年第9期17卷 8542-8551页

作者： Cai-Liang wang Shuang Bai Pei-Yan Zhao Tao Zhou Hui-Ya wang jun-peng wang Luo-Xin wang Guang-Sheng wang School of Chemistry Beihang UniversityBeijing 100191China Aerospace Science and Industry Corporation of Wuhan Magnetoelectricity Co. Ltd.Wuhan 430070China College of Materials Science and Engineering Key Laboratory for New Textile Materials and Applications of Hubei ProvinceWuhan Textile UniversityWuhan 430200China School of Chemistry and Chemical Engineering Lingnan Normal UniversityZhanjiang 524048China School of Materials Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China

Here,we present a unique method to enhance the low-frequency absorption performance of a honeycomb absorber by integrating a *** geometrical dimensions of the proposed metasurface have been numerically *** introduction of the metasurface allows exploitation of its robust resonance and superior impedance matching in low-frequency bands,thereby improving microwave absorption *** incorporation of the metasurface does not impact the wave transmission performance of the honeycomb core absorber at high-frequency band,thus preserving its high-frequency *** broadens the absorption range,leading to an expanded *** results reveal that the composite absorber(CA)exhibits strong absorption performance with an incident angle stability up to 45°for both transverse electric(TE)and transverse magnetic(TM)*** absorption mechanism of the CA has been investigated by using an equivalent circuit model and electromagnetic field analysis.A prototype was designed,fabricated,and tested to validate the proposed *** simulation and measurement results demonstrate that the prototype can achieve an average absorption rate exceeding 90%across a 1.0-18.0 GHz *** study introduces an innovative technique for creating microwave absorbers for low-frequency wideband applications.

关键词： low frequency metasurface radar absorption impedance matching

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Spin-orbit coupling in Bose-Einstein condensate and degenerate Fermi gases

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Frontiers of physics 2014年第5期9卷 598-612页

作者： peng-jun wang Jing Zhang State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-Electronics Shanxi University Taiyuan 030006 China

We review our recent experimental realization and investigation of a spin orbit （SO） coupled Bose Einstein condensate （BEC） and quantum degenerate Fermi gas. By using two counter-propagathlg Ranlan lasers and controlling the different frequency of two R,aman lasers to engineer the atom light interaction, we first study the SO coupling in BEC. Then we study SO coupling in Fermi gas. We, observe the spin dephasing in spin dynamics and momentum distribution asymmetry of the equilibrium state as halhnarks of SO coupling in a Fermi gas. To clearly reveal the, property of SO coupling Fermi gas, we also study the momentmn-resolved radio-frequency spectroscopy which characterizes the energy momentum dispersion and spin composition of the quantum states. We observe the change of errmion surfaces in different helieity branches with different atomic density, which indicates that a Lifshitz transition of the Fermi surface topology change can be found by further cooling the system. At last, we study the momentum-resolved Raman spectroscopy of an ultracoht Fermi gas.

关键词： spin-orbit coupling Bose Einstein condensate Fermi gases topological change momentum-resolved radio-frequency spectroscopy momentum-resolved Raman spectroscopy

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Design of adiabatic two's complement multiplier-accumulator based on CTGAL

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第2期10卷 172-178页

作者： peng-jun wang Jian XU Shi-yan YING Institute of Circuits and Systems Ningbo University Ningbo 315211 China College of Information Engineering Zhej iang University of Technology Hangzhou 310014 China

We propose a new design scheme for a Booth encoder based on clocked transmission gate adiabatic logic(CTGAL). In the new design the structural complexity of the Booth encoder is reduced while the speed of the multiplier is improved. The adiabatic two's complement multiplier-accumulator(MAC) is furthermore a design based on the CTGAL. The computer simulation results indicate that the designed circuit has the correct logic function and remarkably less energy consumption compared to that of the MAC based on complementary metal oxide semiconductor(CMOS) logic.

关键词： CTGAL circuit Adiabatic circuit Booth arithmetic Multiplier Two's complement MAC

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Influence of microwave treatment on grinding and dissociation characteristics of vanadium titano-magnetite

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International Journal of Minerals,Metallurgy and Materials 2019年第2期26卷 160-167页

作者： jun-peng wang Tao Jiang Ya-jing Liu Xiang-xin Xue School of Metallurgy Northeastern University Key Laboratory of Liaoning Province for Recycling Science of Metallurgical Resources

The effect of microwave treatment on the grinding and dissociation characteristics of vanadium titano-magnetite(VTM) ore were investigated using scanning electron microscopy(SEM), nitrogen absorption measurements, particle size distribution measurements, X-ray diffraction(XRD) analysis, Fourier transform infrared(FT-IR) spectroscopic analysis, and magnetic separation. SEM analysis showed that microfractures appeared in the microwave-treated VTM, which is attributed to the microwaves' selective heating characteristic and the differential expansion between minerals and gangues. Nitrogen absorption showed that the microfractures were more pronounced when the microwave heating time was increased. Particle size distribution analysis showed that microwave treatment could improve the grindability of the VTM, thus increasing the weight percent of the fine-ground product. The increase in grindability was more significant with prolonged heating time. Moreover, the particle size distribution of the fine-ground product changed only slightly after the microwave treatment. XRD analysis showed that the crystallinity of the microwave-treated VTM increased with increasing microwave heating time. The magnetic separation tests revealed that the separation efficiency increased as a result of the intergranular fractures generated by microwave treatment. The Fe grade of the magnetic fraction of microwave-treated VTM was 1.72% higher than that of the raw ore. We concluded that the microwave treatment was beneficial, especially for the mineral processing characteristics.

关键词： microwave treatment vanadium titano-magnetite grinding microstructure magnetic separation

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Efficient production of ultracold polar molecules^(23)Na^(40)K in their absolute ground state via intermediate state of the coupled complex B^(1)Π|ν=4〉^(c)^(3)Σ^(+)|ν=25〉

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中国科学:物理学、力学、天文学英文版 2023年第9期66卷 42-49页

作者： Zi-Liang Li Zheng-Yu Gu peng-jun wang Jing Zhang State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-electronicsShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

We report on the efficient creation of a sample of 2.2×10^(4)fermionic polar molecules^(23)Na^(40)K in their rovibrational ground state X^(1)∑^(+)|v=0,J=0>at 247 nK via an intermediate state of the spin-orbit coupled complex B^(1)Π|v=4〉~C^(3)∑^(+)|v=25〉.Compared with the intermediate state of the coupled complex B^(1)Π|v=12〉^(c)^(3)∑^(+)|v=35〉,this intermediate state has the larger Franck-Condon factors for up-and down-leg coupling of stimulated Raman adiabatic passage(STIRAP).We demonstrate this two-photon pathway to the^(23)Na^(40)K ground state molecules and find that the one-way STIRAP transfer efficiency reaches75%.The molecules^(23)Na^(40)K in their rovibrational ground state are an ideal candidate for the quantum simulation and quantum information of ultracold molecules with long-range interaction.

关键词： ultracold atoms ultracold molecule STIRAP

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Tunable valley filter efficiency by spin-orbit coupling in silicene nanoconstrictions

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Chinese Physics B 2021年第5期30卷 589-594页

作者： Yi-Jian Shi Yuan-Chun wang peng-jun wang College of Electrical and Electronic Engineering Wenzhou UniversityWenzhou 325035China

Valley filter is a promising device for producing valley polarized current in graphene-like two-dimensional honeycomb lattice *** relatively large spin-orbit coupling in silicene contributes to remarkable quantum spin Hall effect,which leads to distinctive valley-dependent transport properties compared with intrinsic *** this paper,quantized conductance and valley polarization in silicene nanoconstrictions are theoretically investigated in quantum spin-Hall insulator *** perfect valley filter effect is found by aligning the gate voltage in the central constriction ***,the valley polarization plateaus are shifted with the increase of spin-orbit coupling strength,accompanied by smooth variation of polarization *** findings provide new strategies to control the valley polarization in valleytronic devices.

关键词： valley polarization spin-orbit coupling quantization silicene

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Efectiveness and petroleum geological signifcance of tectonic fractures in the ultra‑deep zone of the Kuqa foreland thrust belt:a case study of the Cretaceous Bashijiqike Formation in the Keshen gas feld

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Petroleum Science 2021年第3期18卷 728-741页

作者： Rong-Hu Zhang Ke wang Qing-Lu Zeng Chao-Feng Yu jun-peng wang PetroChina Research Institute of Petroleum Exploration and Development Beijing 100086China PetroChina Hangzhou Research Institute of Geology Hangzhou 310023ZhejiangChina

The buried depth of the gas-producing reservoir in the Kuqa foreland thrust belt of the Tarim Basin exceeds 6000 *** average matrix porosity of the reservoir is 5.5%,and the average matrix permeability is 0.128×10^(−3)μm^(2).In order to reveal the characteristics and efectiveness of ultra-deep fractures and their efects on reservoir properties and natural gas production,outcrops,cores,thin section,image logs and production testing data are used to investigate the efectiveness of tectonic fractures in ultra-deep reservoirs in the Kuqa foreland thrust zone,and the corresponding geological signifcance for oil and gas exploration and development are *** fractures in the thrust belt include EW-trending high-angle tensile fractures and NS-trending vertical shear *** former has a relatively high flling rate,while the latter is mostly ***-fractures are usually grain-piercing-through cracks with width of 10-100 *** the planar view,the efective fractures are concentrated in the high part and wing zones of the long axis of the anticline,and along the vertical direction,they are mainly found in the tensile fracture zone above the neutral *** adjustment fracture zone has the strongest vertical extension abilities and high efectiveness,followed by the nearly EW longitudinal tensile fracture zone,and the netted fracture zone with multiple dip *** efectiveness of fracture is mainly controlled by fracture aperture and flling *** fractures can increase reservoir permeability by 1-2 orders of *** higher part of the anticline is associated with high tectonic fracture permeability,which control enrichment and high production of natural *** netted vertical open fractures efectively communicate with pores and throats of the reservoir matrix,which forms an apparent-homogenous to medium-heterogeneous body that is seen with high production of natural gas sustained for a long term.

关键词： Fracture efectiveness Ultra-deep Reservoir Foreland thrust belt Kuqa depression Geological signifcance

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Genetic Relation Analysis on Ramie[Boehmeria nivea(L.)Gaud.]Inbred Lines by SRAP Markers

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Agricultural Sciences in China 2008年第8期7卷 944-949页

作者： LIU Li-jun peng Ding-xiang wang Bo College of Plant Science and Technology Huazhong Agricultural University Wuhan 430070 P.R.China

The objective of this article is to reveal the variations of ramie inbred lines in DNA level and discuss their molecular background to provide a theoretical basis for ramie cross breeding. In the present study, the genetic relationships among 33 inbred line accessions and two wild types that originated from China and Brazil were estimated using sequence-related amplified polymorphism （SRAP） markers. The results showed that 33 out of 81 primer combinations turned out to be polymorphic and 332 polymorphism bands were obtained. On the basis of the appearance of the markers, the genetic relationships were analyzed using unweighted pair-group method of arithmetic average cluster analysis （UPGMA）, and the genetic Jaccard similarity coefficients were calculated. The inbred-lines originating from China and Brazil formed a cluster suggesting a possibility that the Brazilian cultivars could have developed from cultivars introduced from China. Within ramie inbred-lines, the groupings also indicated that the greatest genetic relationship among cultivars was correlated to the region of origin of cultivars. The results provided the evidence that SRAP was an efficient approach, suitable for taxonomic analysis of ramie inbred lines, To the authors＇ knowledge, this is the first application of SRAP marker on the systematics of ramie inbred lines.

关键词： relatives of ramie inbred lines SRAP taxonomic analysis UPGMA

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Organic matter and concentrated nitrogen removal by shortcut nitrification and denitrification from mature municipal landfill leachate

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Journal of Environmental Sciences 2007年第6期19卷 647-651页

作者： ZHANG Shu-jun peng Yong-zhen wang Shu-ying ZHENG Shu-wen GUO Jin College of Environmental and Energy Engineering Beijing University of Technology Beijing 100022 China

An UASB＋Anoxic/Oxic （A/O） system was introduced to treat a mature landfill leachate with low carbon-to-nitrogen ratio and high ammonia concentration. To make the best use of the biodegradable COD in the leaehate, the denitrifieation of NOx^--N in the reeireulation effluent from the elarifier was carried out in the UASB. The results showed that most biodegradable organic matters were removed by the denitrifieation in the UASB. The NH4^＋-N loading rate （ALR） of A/O reactor and operational temperature was 0.28- 0.60 kg NH4^＋-N/（m^3-d） and 17-29℃ during experimental period, respectively. The short-cut nitrification with nitrite accumulation efficiency of 90%-99% was stabilized during the whole experiment. The NH4^＋-N removal efficiency varied between 90% and 100%. When ALR was less than 0.45 kg NH4^＋-N/（m^3.d）, the NH4^＋-N removal efficiency was more than 98%. With the influent NH4^＋-N of 1200-1800 mg/L, the effluent NH4^＋-N was less than 15 mg/L. The shortcut nitrification and denitrifieation can save 40% carbon source, with a highly efficient denitrifieation taking place in the UASB. When the ratio of the feed COD to feed NH4^＋-N was only 2-3, the total inorganic nitrogen （TIN） removal efficiency attained 67%-80%. Besides, the sludge samples from A/O reactor were analyzed using FISH. The FISH analysis revealed that ammonia oxidation bacteria （AOB） accounted for 4% of the total eubaeterial population, whereas nitrite oxidation bacteria （NOB） accounted only for 0.2% of the total eubaeterial population.

关键词： mature landfill leachate UASB+A/O shortcut nitrification carbon source

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Interventional treatment for symptomatic acute-subacute portal and superior mesenteric vein thrombosis

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World Journal of Gastroenterology 2009年第40期15卷 5028-5034页

作者： Feng-Yong Liu Mao-Qiang wang Qing-Sheng Fan Feng Duan Zhi-jun wang peng Song Department of Interventional Radiology Clinical Division of Internal Medicine Chinese People's Liberation Army General Hospital Beijing 100853 China

AIM: To summarize our methods and experience with interventional treatment for symptomatic acute-sub-acute portal vein and superior mesenteric vein throm-bosis (PV-SMV) thrombosis. METHODS: Forty-six patients (30 males, 16 females, aged 17-68 years) with symptomatic acute-subacute portal and superior mesenteric vein thrombosis were ac-curately diagnosed with Doppler ultrasound scans, com-puted tomography and magnetic resonance imaging. They were treated with interventional therapy, including direct thrombolysis (26 cases through a transjugular intrahepatic portosystemic shunt; 6 through percutane-ous transhepatic portal vein cannulation) and indirect thrombolysis (10 through the femoral artery to superior mesenteric artery catheterization; 4 through the radial artery to superior mesenteric artery catheterization). RESULTS: The blood reperfusion of PV-SMV was achieved completely or partially in 34 patients 3-13 d after thrombolysis. In 11 patients there was no PV-SMV blood reperfusion but the number of collateral vessels increased signif icantly. Symptoms in these 45 patients were improved dramatically without severe operationalcomplications. In 1 patient, the thrombi did not respond to the interventional treatment and resulted in intestinal necrosis, which required surgical treatment. In 3 patients with interventional treatment, thrombi reformed 1, 3 and 4 mo after treatment. In these 3 patients, indirect PV-SMV thrombolysis was performed again and was successful. CONCLUSION: Interventional treatment, including direct or indirect PV-SMV thrombolysis, is a safe and effective method for patients with symptomatic acutesubacute PV-SMV thrombosis.

关键词： Portal thrombosis Superior mesenteric vein thrombosis Thrombolysis Interventional treatment

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