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Linear and Nonlinear Spectra in Photosynthetic Light Harvesting Complexes: Benchmark Tests of Modified Redfield Method

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Chinese Journal of Chemical Physics 2015年第4期28卷 -页

作者： Yuan-yuan Jing Kai Song Shu-ming bai Qiang Shi Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100190China

We employ the numerically exact hierarchical equations of motion (HEOM) method to perform benchmark tests for the popular modified Redfield method in calculating linear and nonlinear spectroscopic signals of molecular aggregates in photosynthetic light harvesting complexes. It is currently well known that the perturbative and Markovian approximations involved in the modified Redfield equation may give inappropriate description of the excitation energy transfer processes in the intermediate coupling regime. An interesting topic is thus to test the validity of the modified Redfield method in calculating various types of spectroscopic signals. By using model dimers with different sets of parameters and a model of the Fenna-Matthews-Olson complex, we calculate and compare the absorption, emission, and 2D spectra using the modified Redfield and HEOM methods. It is found that results from the modified Redfield method agree well with the HEOM ones in a wide range of parameter regimes. The comparison also helps to understand the quantum beating signals in the 2D spectra of the photosynthetic light harvesting complexes.

关键词： Linear spectra Nonlinear spectra Light harvesting complexes Modified Redfield method

Science Letters:Peak-power reduction by the lattice-reduction-aided closest point search for MIMO broadcast channels

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第10期9卷 1326-1330页

作者： Jian-ping ZHENG Bao-ming bai Xin-mei WANG State Key Laboratory of Integrated Services Networks Xidian University Xi ＇an 710071 China

In this letter, we present a modified vector-perturbation precoding scheme for the multiple-input multiple-output broadcast channel, where a perturbation vector is chosen to take into account both the instantaneous power and the instantaneous peak power of the transmitted signal. This perturbation vector is obtained by using the closest point search, with the aid of the lattice-reduction algorithm. Simulation results show that the proposed scheme yields a tradeoff among power efficiency, peak-to-average power ratio reduction, and complexity.

关键词： Multiple-input multiple-output (MIMO) Broadcast channel (BC) Precoding Peak-to-average power ratio (PAPR) Lattice-reduction (LR)

Sequential Quantum Secret Sharing Using a Single Qudit

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Communications in Theoretical Physics 2018年第5期69卷 513-518页

作者： Chen-ming bai Zhi-Hui Li and Yong-ming Li College of Mathematics and Information Science Shaanxi Normal University Xi＇an 710119 China College of Computer Science Shaanxi Normal University Xi＇an 710119 China

In this paper we propose a novel and efficient quantum secret sharing protocol using d-level single particle,which it can realize a general access structure via the thought of concatenation. In addition, Our scheme includes all advantages of Tavakoli's scheme [Phys. Rev. A 92 (2015) 030302(R)]. In contrast to Tavakoli's scheme, the efficiency of our scheme is 1 for the same situation, and the access structure is more general and has advantages in practical significance. Furthermore, we also analyze the security of our scheme in the primary quantum attacks.

关键词： quantum secret sharing access structure threshold scheme

What determines the observational differences of blazars？

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Research in Astronomy and Astrophysics 2016年第11期16卷 61-70页

作者： Xu-Liang Fan Jin-ming bai Ji-Rong Mao Yunnan Observatories Chinese Academy of Sciences Kunming 650011 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650011 China University of Chinese Academy of Sciences Beijing 100049 China

We examine the scenario that the Doppler factor determines the observational differences of blazars. Significantly negative correlations are found between the observational synchrotron peak frequency and the Doppler factor. After correcting the Doppler boosting, the intrinsic peak frequency has a tight linear relation with the Doppler factor. It is interesting that this relation is consistent with the scenario that the black hole mass governs both the bulk Lorentz factor and the synchrotron peak frequency. In addition, the distinction between the kinetic jet powers of BL Lac objects and fiat spectrum radio quasars disappears after the boosting factor δ2 is considered. The negative correlation between the peak frequency and the observational isotropic luminosity, known as the blazar sequence, also disappears after the Doppler boosting is corrected. We also find that the correlation between the Compton dominance and the Doppler factor exists for all types of blazars. Therefore, this correlation is unsuitable for examining the external Compton emission dominance.

关键词： galaxies: jets - BL Lacertae objects: general - quasars: general - radiation mechanisms:non-thermal

SCISSORS DIFFERENCE AND ITS IMPACTS ON ECONOMIC VALUE OF CULTIVATED LAND IN CHINA

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Chinese Geographical Science 2005年第3期15卷 193-199页

作者： WANG Xiu-fen CHEN bai-ming BI Ji-ye Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101 P. R. China Graduate School of Chinese Academy of Sciences Beijing 100039 P. R. China China lnstitute of Land and Surveying Ministry of Land and Resources Beijing 100035 P. R. China

The problem of price scissors difference between industrial products and agricultural products is one of the important problems in China. It impacts not only the living standard improvement of farmers but also the economic value of cultivated land, furthermore results in the direct and indirect loss of cultivated land resources. China＇s cultivated land area has decreased dramatically in recent years. An important reason for the decrease is the relatively low cost of cultivated land occupancy, which results from the distortion of economic value of cultivated land due to the existence of scissors difference. This study firstly analyzed the dynamic change of scissors difference and calculated the absolute and relative magnitude of scissors difference from 1997 to 2002, then computed the economic value of cultivated land before and after scissors difference adjustment in 2002, and finally discussed the inverted scissors difference. Results suggest that the scissors difference has a remarkable impact on the economic value of cultivated land, and the adjustment of scissors difference even inverted scissors difference to the economic value of cultivated land is indisoensable.

关键词： cultivated land economic value scissors difference scissors difference adjustment P. R. China

New fossil evidence of the early diversification of scarabs： AIIoioscarabaeus cheni （Coleoptera： Scarabaeoidea） from the Middle Jurassic of Inner Mongolia, China

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Insect Science 2012年第2期19卷 159-171页

作者： ming bai Dirk Ahrens Xing-Ke Yang Dong Ren Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijingChina Zoologisches Forschungsmuseum Alexander Koenig BonnGermany College of Life Sciences Capital Normal UniversityBeijingChina

Scarabaeoidea are known from the Lower Jurassic and may have originated in the Triassic based on fossil evidence and phylogenetic research. However, the early diversification of Scarabaeoidea remains unclear due to the lack of high-quality fossil evidence. Here we describe an exceptionally well-preserved new fossil of Scarabaeoidea, Alloioscarabaeus cheni gen. et sp. nov from the Middle Jurassic Jiulongshan Formation of Inner Mongolia, China. Based on a morphometric analysis using 17 landmarks of the hind wing of Alloioscarabaeus and 10 scarabaeoid families, we found that Alloioscarabaeus cheni gen. et sp. nov clearly does not belong to any of the known scarabaeoid families and, consequently, is a new family, Alloioscarabaeidae fam. nov., was erected. The discovery of Alloioscarabaeus brought further evidence for the early diversification of major scarab lineages which could allow more detail in the palaeobiogeography of the Scarabaeoidea and Northeast of China which might be one of the originating places or an important radiation place during the evolution of Scarabaeoidea. Alloioscarabaeidae were very likely not good diggers and might have fed on decaying organic materials. Based on the evidence we have now, we tend to believe that most families and some subfamilies of Scarabaeoidea were present in the Jurassic period.

关键词： Alloioscarabaeidae Alloioscarabaeus China geometric morphometrics,Jiulongshan Formation new family

Low-voltage soft robots based on carbon nanotube/polymer electrothermal composites

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Chinese Physics B 2022年第12期31卷 703-709页

作者： Qi Wang Ying-Qiong Yong Zhi-ming bai School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China R&D Department China Academy of Launch Vehicle TechnologyBeijing 100076China

Nowadays,soft robots have become a research hot spot due to high degree of freedom,adaptability to the environment and safer interaction with *** carbon nanotube(CNT)/polydimethylsiloxane(PDMS)electrothermal composites have attracted wide attention in the field of flexible actuations due to large deformation at low ***,the preparation process of CNT/PDMS composites was designed and optimized,and electrothermal actuators(ETAs)were fabricated by cutting the CNT/PDMS composite films into a“U”shape and coating conductive *** deformation performance of the ETAs with different thicknesses at different voltages was *** a low voltage of about 7 V,the ETA has a deformation rate of up to 93%.Finally,two kinds of electrothermal soft robots(ETSRs)with four-legged and three-legged structures were fabricated,and their inchworm-like motion characteristics were *** ETSR2 has the best motion performance due to the moderate thickness and three-legged electrode structure.

关键词： carbon nanotube(CNT) polydimethylsiloxane(PDMS) electrothermal actuator soft robot

Urban vitality assessment at the neighborhood scale with geo-data:A review toward implementation

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Journal of Geographical Sciences 2023年第7期33卷 1482-1504页

作者： LIU Sheng GE Jian YE Xinyue WU Chao bai ming College of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310058China Hangzhou City University Hangzhou 310011China Department of Landscape Architecture and Urban Planning Texas A&M UniversityCollege StationTX 77840USA School of Geographic and Biologic Information Nanjing University of Posts and TelecommunicationsNanjing 210023China Zhejiang University Urban-Rural Planning&Design Institute Hangzhou 310030China

The number of urban vitality assessment studies is rising continuously,owing to the emergence of geographic *** current literature focuses primarily on evaluation,rather than implementation,of urban ***,a scoping review and research agenda are needed for urban vitality research to be more *** study aims to fill the research gap by exploring the content and methods of vitality assessment that can make urban vitality research more compatible with policy,planning,and design *** chose the neighborhood scale,which is the most practical initiative unit for vitality *** discovered that the gaps between the current research and practice primarily lie in the diversity of research subjects,the authenticity and comprehensiveness of vitality measurement,and the multi-domain of impact factor *** this basis,we classified the following expandable aspects:(1) multi-type,multi-dimensional,multi-temporal,and implementation-adaptive vitality evaluation;(2) methods reflecting high-quality social interactions and the perceptions of vulnerable groups;(3) how design and urban management impacts vitality;and(4) the synergistic effects of multiple indicators on ***,the research content and methodology presented in this paper can help neighborhood-scale vitality assessment to provide more meaningful insights for policy makers and practitioners.

关键词： urban vitality neighborhood scale implementation geo-data

Selection of a TIPS stent for management of portal hypertension in liver cirrhosis: An evidence-based review

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World Journal of Gastroenterology 2014年第21期20卷 6470-6480页

作者： Xing-Shun Qi ming bai Zhi-Ping Yang Dai-ming Fan Xijing Hospital of Digestive Diseases Fourth Military Medical University Department of Gastroenterology No. 463 Hospital of Chinese PLA

Nowadays,transjugular intrahepatic portosystemic shunt(TIPS)has become a mainstay treatment option for the management of portal hypertension-related complications in liver *** evidence has shown that its indications are being gradually ***,less attention has been paid for the selection of an appropriate stent during a TIPS ***,we attempt to review the current evidence regarding the diameter,type,brand,and position of TIPS *** following recommendations may be considered in the clinical practice:(1)a 10-mm stent may be more effective than an 8-mm stent for the management of portal hypertension,and may be superior to a 12-mm stent for the improvement of survival and shunt patency;(2)covered stents are superior to bare stents for reducing the development of shunt dysfunction;(3)if available,Viatorr stent-grafts may be recommended due to a higher rate of shunt patency;and(4)the placement of a TIPS stent in the left portal vein branch may be more reasonable for decreasingthe development of hepatic ***,given relatively low quality of evidence,prospective well-designed studies should be warranted to further confirm these recommendations.

关键词： Transjugular intrahepatic portosystemic shunt Portal hypertension Liver cirrhosis Variceal bleeding Hepatic encephalopathy Shunt dysfunction