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Design of good QC-LDPC codes without small girth in the p-plane

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Journal of Systems Engineering and Electronics 2011年第2期22卷 183-187页

作者： lingjun kong yang xiao Institute of Information Science Beijing Jiaotong University Beijing 100044 E R. China Faculty of Information Engineering and Automation Kunming University of Science and Technology Kunming 650500 P. R. China

A construction method based on the p-plane to design high-girth quasi-cyclic low-density parity-check （QC-LDPC） codes is proposed. Firstly the good points in every line of the p-plane can be ascertained through filtering the bad points, because the designed parity-check matrixes using these points have the short cycles in Tanner graph of codes. Then one of the best points from the residual good points of every line in the p-plane will be found, respectively. The optimal point is also singled out according to the bit error rate （BER） performance of the QC-LDPC codes at last. Explicit necessary and sufficient conditions for the QC-LDPC codes to have no short cycles are presented which are in favor of removing the bad points in the p-plane. Since preventing the short cycles also prevents the small stopping sets, the proposed construction method also leads to QC-LDPC codes with a higher stopping distance.

关键词： quasi-cyclic low-density parity-check (QC-LDPC)codes circulant matrices girth stopping set stopping distance.

LLR calculation for LDPC coded SCBT in 60 GHz WPAN

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Journal of Systems Engineering and Electronics 2010年第5期21卷 734-739页

作者： lingjun kong yang xiao Ming Lei Ye Huang Institute of Information Science Beijing Jiaotong University Beijing 100044 E R. China NEC Laboratories NEC Corporation Beijing 100084 P. R. China Communications Technology Laboratories Intel China Research Center Beijing 100080 E R. China

The single-carrier block transmission（SCBT）,a.k.a.,single-carrier frequency-domain equalization（SC-FDE）,is being considered as an option technique for the wireless personal area network（WPAN） operating at 60 *** is found that for residential environment,in non-line-of-sight（NLOS） multi-path channels,the SCBT is much more effective to combat the inter-symbol interference（ISI） compared with orthogonal frequency division multiplexing（OFDM）.Low-density parity-check（LDPC） codes are a class of linear block codes which provide near capacity performance on a large collection of data transmission and storage channels while simultaneously admitting implementable *** facilitate using LDPC codes for SCBT system,a new log-likelihood ratio（LLR） calculation method is proposed based on pilot symbols（PS）.Golay Sequences whose sum autocorrelation has a unique peak and zero sidelobe are used for creating the *** position and length of the PS are not fixed in the data *** simulation results show that the proposed method can significantly improve the LDPC decoding performance in SCBT *** is very promising to support ultra high-data-rate wireless transmission.

关键词： single-carrier block transmission single-carrier frequency-domain equalization low-density parity-check code log-likelihood ratio wireless personal area network.

Structure and Thermochromic Property of a Silver(I) Complex Based on Dicyanamide and Phosphine Ligands

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Chinese Journal of Structural Chemistry 2020年第7期39卷 1301-1306页

作者： XU Bo yang xiao-Dong kong Ling-Xue School of Chemistry and Chemical Engineering University of JinanJinan 250022China

A new silver(I)complex{Ag2(dppm)2[N(CN)2]}2[μ-N(CN)2]2(1)with chelate ligand bis(diphenylphosphino)methane(dppm)and bridging ligand dicyanamide(N(CN)2)was carefully synthesized and fully characterized by single-crystal X-ray crystallography,IR spectrometry,high-resolution mass spectrometry,thermal analysis and 1H *** to the crystal structure analysis,this complex could be considered as two binucleate moieties{Ag2(dppm)2[N(CN)2]}+linked by two bridging anionic ligands N(CN)2-.It exhibits thermochromic property in solid *** dependence of color or emission of substance on temperature is known as *** temperature luminescences of complex 1 are *** with the reduction of temperature from 298 K to 77 K,a noticeable emission enhancement as well as lifetime extension is observed.

关键词： silver complex crystal structure dicyanamide bis(diphenylphosphino)methane thermochromic property

Enhanced post-combustion CO2 capture and direct air capture by plasma surface functionalization of graphene adsorbent

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Journal of Energy Chemistry 2025年第1期100卷 653-664页

作者： Rahul Navik Eryu Wang xiao Ding Huang Yunyi Yiyu Liu Jia Li Guangdong-Hong kong Joint Laboratory for Carbon Neutrality Jiangmen Laboratory of Carbon and Science and Technology Guangzhou HKUST Fok Ying Tung Research Institute The Hong kong University of Science and Technology (Guangzhou) Carbon Neutrality and Climate Change Thrust Society Hub The Hong Kong University of Science and Technology (Guangzhou) Stoddart Institute of Molecular Science Department of Chemistry Zhejiang University

Graphene has enormous potential to capture CO2due to its unique properties and ***,graphene-based adsorbents have drawbacks of lower CO2adsorption capacity and poor *** work demonstrates a one-step rapid and sustainable N2/H2plasma treatment process to prepare graphene-based sorbent material with enhanced CO2adsorption *** treatment directly enriches amine species,increases surface area,and improves textural *** CO2adsorption capacity increases from 1.6 to 3.3 mmol/g for capturing flue gas,and from 0.14 to 1.3 mmol/g for direct air capture （DAC）.Importantly,the electrothermal property of the plasma-modified aerogels has been significantly improved,resulting in faster heating rates and significantly reducing energy consumption compared to conventional external heating for regeneration of *** aerogels display improved selectivity of 42 and 87 after plasma modification for 5 and 10 min,*** plasma-treated aerogels display minimal loss between 17%and 19% in capacity after 40 adsorption/desorption cycles,rendering excellent *** N2/H2plasma treatment of adsorbent materials would lower energy expenses and prevent negative effects on the global economy caused by climate change.

关键词： Carbon neutrality CO 2 capture Climate change Plasma treatment Graphene aerogel

Fabricating high-performance sodium ion capacitors with P2-Na_(0.67)Co_(0.5)Mn_(0.5)O_2 and MOF-derived carbon

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Journal of Energy Chemistry 2019年第1期28卷 79-84页

作者： Haichen Gu lingjun kong Huijuan Cui Xianlong Zhou Zhaojun Xie Zhen Zhou School of Materials Science and Engineering National Institute for Advanced Materials Institute of New Energy Material Chemistry Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Nankai University

Sodium ion capacitors(SICs) have been considered as a kind of promising devices to achieve both high power and energy density. However, it is still a challenge to achieve high energy output at elevated power delivery due to the poor rate capability of battery-type electrode materials and the kinetic mismatch with capacitor-type electrode materials. In this work, to fabricate SICs, P2-Na_(0.67)Co_(0.5)Mn_(0.5)O_2(P2-NCM)was chosen as the battery-type cathode material, and a typical metal-organic framework(MOF) material,zeolitic imidazolate framework-8(ZIF-8) derived carbon(ZDC) was utilized as the capacitor-type anode material. Due to the kinetic match and high-rate performance of both electrodes, the ZDC//P2-NCM SICs exhibited an energy output of 18.8 Wh kg^(-1) at a high power delivery of 12.75 kW kg^(-1).

关键词： Energy density Power density P2-phase material Zeolitic imidazolate framework-8 Sodium ion capacitors

Geochemistry and Tectonic History of Seamount Remnants in the Xingshuwa Subduction Accretionary Complex of the Xar Moron Area,Eastern Margin of the Central Asian Orogenic Belt

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1086-1098页

作者： CHENG yang xiao Qinghui LI Tingdong LI Yan FAN Yuxu XU Liquan GUO lingjun PANG Jinli Institute of Mineral Resources Research China Metallurgical GeologyBureauBeijing 101300China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China General Prospecting Institute China National Administration of Coal GeologyBeijing 100039China Inner Mongolia Key Laboratory of Magmatic Mineralization and Ore-Prospecting Hohhot 010020China

This study focuses on the geology,geochemistry,zircon U-Pb geochronology and tectonic settings of the three types of seamount basalts from the Xingshuwa subduction accretionary complex in the Xar Moron area,eastern margin of the Central Asian Orogenic Belt(CAOB).The seamount remnants are composed of carbonate’cap’sediments,large volumes of pillow and massive basalts,carbonate breccia slope facies and radiolarian *** 1 basalts are characterized by high contents of P2 O5 and TiO2 with alkaline affinity and LREE enrichment,indicating that they are derived from intraplate *** 2 basalts display N-MORB LREE depletion patterns,indicating that they were formed at a mid-ocean *** 3 basalts have shown distinct Nb depletion and high Th/Yb ratios,indicating that they were generated in an island arc tectonic *** zircon U-Pb age of Group 1 basalt sample XWT18-131 is 576.4±9.4 Ma,suggesting that the oceanic island seamount was the product of intraplate magmatism related to a mantle plume or’hot spot’in the late *** zircon U-Pb age of Group 2 basalt sample XWT18-132 is 483±22 Ma,indicating that the Paleo-Asian Ocean(PAO)was continuously expanding in the Early *** zircon U-Pb age of Group 3 basalt sample XWT18-101 is 240.5±8.2 Ma,suggesting that this area underwent the evolutionary path of ocean-continent transition,developing towards continentalization during the Middle ***,we believe that there was both mantle plume-related intraplate magmatism and intraoceanic subduction during the evolution of the PAO,the CAOB possibly being an evolutionary model of an intraoceanic subduction and mantle plume magmatism complex.

关键词： seamount geochemistry U-Pb geochronology of zircons tectonic setting Paleo-Asian Ocean

Spatial and Temporal Distributions of Atmospheric CO2 in East China Based on Data from Three Satellites

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Advances in Atmospheric Sciences 2020年第12期37卷 1323-1337页

作者： Bozhen LI Gen ZHANG lingjun XIA Ping kong Mingjin ZHAN Rui SU Jiangxi Ecological Meteorology Center Nanchang 330096China State Key Laboratory of Severe Weather&Key Laboratory of Atmospheric Chemistry of China Meteorological Administration Chinese Academy of Meteorological SciencesBeijing 100081China Jiangxi Atmospheric Detection Technology Center Nanchang 330096China

East China(23.6°–38.4°N,113.6°–122.9°E)is the largest developed region in *** on CO2 products retrieved from the Greenhouse Gases Observing Satellite(GOSAT),the spatial and temporal distributions of CO2 mixing ratios in East China during 2014–17 are discussed,and the retrieved CO2 from AIRS(Atmospheric Infrared Sounder)and OCO-2(Orbiting Carbon Observatory-2),as well as WLG(Waliguan)background station observations,are compared with those of *** annual CO2 retrieved from GOSAT in East China ranged from 398.96±0.24 ppm in 2014 to 407.39±0.20 ppm in 2017,with a growth rate of 2.82±0.15 ppm yr^−1,which were higher than in other regions of *** seasonal cycle presented a maximum in spring and a minimum in summer or *** values were mainly concentrated in the coastal areas of Zhejiang Province,and lower values were concentrated in Jiangxi and the north of Fujian ***2 observed in Fujian and parts of Jiangxi increased by less than 1.0 ppm during 2014–15,but enhanced significantly by more than 5.0 ppm during 2015–16,perhaps influenced by local emissions and global *** calculated year-to-year CO2 enhancements in the yangtze River Delta region during 2014–17 that were relatively low and stable,due to the region’s carbon emissions control and reduction *** annual and seasonal amplitudes of CO2 retrieved from AIRS were lower than those from GOSAT in East China,probably owing to the CO2 retrieved from AIRS better reflecting the characteristics of the mid-troposphere,while GOSAT is more representative of near-surface *** spatial and temporal distribution characteristics of CO2 retrieved from OCO-2 were close to those from GOSAT in East China.

关键词： CO2 East China GOSAT AIRS OCO-2

Effect of Disturbances on the Operation Process of a Methane-Fueled Free-Piston Engine Generator

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Journal of Thermal Science 2023年第2期32卷 881-896页

作者： HUANG Fujun xiao Huihui GUO Shuman WANG Lijun yang Zhenzhong kong Wenjun School of Mechanics North China University of Water Resources and Electric PowerHenan 450045China Henan International Joint Laboratory of Thermo-Fluid Electro-Chemical System for New Energy Vehicle Henan 450045China School of Astronautics Beihang UniversityBeijing 102206China

In this paper,the effect of disturbances on the operation process of a methane-fueled free-piston engine generator(FPEG)was experimentally *** disturbance sources,namely step change of external load,mixture flow rate fluctuation,random misfire of a cylinder,and elastic collision,were identified and applied to the *** results showed that the FPEG successfully achieved a steady-state operation with *** maximum instantaneous electric power of 127 W and the average effective electric power of 38.9 W were *** an external load was instantaneously disconnected,the engine frequency increased from 26.7 Hz to 31.3 *** fluctuation amplitudes of induced voltage,pressure and compression ratio were 18.9%,24.7%and 52.2%respectively in the *** contrast,when the external load was instantaneously connected,the corresponding values were 42.2%,31.3%and 64.3%respectively,indicating that the instantaneous external load connection had a greater disturbance impact on the FPEG operation *** encountering the step change of external load,the FPEG can still restore stable operation and show good anti-disturbance *** with increasing mixture flow rate,reducing the mixture flow rate has a greater disturbance impact on the engine operation *** random misfire of a cylinder will cause remarkable fluctuations in piston displacement and cylinder pressure,the FPEG will not stop running,but continues to work as a single-piston *** collision event may adversely affect the stability of engine operation,but will not lead to the FPEG ***,serious collision event may lead to ignition failure and shutdown accident.

关键词： free-piston engine generator disturbance sources operation stability anti-disturbance ability

A facile synthesis of ω-aminoalkyl ammonium hydrogen phosphates

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Chinese Chemical Letters 2012年第8期23卷 923-926页

作者： Wei Bo kong xiao Yong Zhou yang yang Xing Yi Xie Department of Polymeric Biomaterials and Artificial Organs College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China

A series of og-aminoalkyl ammonium hydrogen phosphates were synthesized through a simple and efficient three-step method. The starting materials, co-aminoalkyl alcohols （AC-n, with carbon number n = 3, 4, 5, 6）, were amino-protected with 9- fluorenylmethyl chloroformate （Fmoc-C1）, followed by phosphorylation with POCI3 and deprotection in piperidine/DME The structures of each intermediate and final product were confirmed by 1H NMR, FTIR and mass spectrum. The yield of each step was about 77-92%, with a total yield higher than 56%. This new method was superior in low-cost raw materials, mild reaction temperatures （0-25 ℃） and easy purification methods.

关键词： Amino alcohol Phosphorus oxychloride Synthesis Aminoalkyl ammonium hydrogen phosphate