Moiré patterns formed by stacking atomically-thin van der Waals crystals with a relative twist angle can give rise to dramatic new physical properties. The study of moiré materials has so far been ...limited to structures comprising no more than a few vdW sheets, since a moiré pattern localized to a single two-dimensional interface is generally assumed to be incapable of appreciably modifying the properties of a bulk three-dimensional crystal. Layered semimetals such as graphite offer a unique platform to challenge this paradigm, owing to distinctive properties arising from their nearly-compensated electron and hole bulk doping. Here, we perform transport measurements of dual-gated devices constructed by slightly rotating a monolayer graphene sheet atop a thin bulk graphite crystal. We find that the moiré potential transforms the electronic properties of the entire bulk graphitic thin film. At zero and small magnetic fields, transport is mediated by a combination of gate-tunable moiré and graphite surface states, as well as coexisting semimetallic bulk states that do not respond to gating. At high field, the moiré potential hybridizes with the graphitic bulk states owing to the unique properties of the two lowest Landau bands of graphite. These Landau bands facilitate the formation of a single quasi-two-dimensional hybrid structure in which the moiré and bulk graphite states are inextricably mixed. Our results establish twisted graphene-graphite as the first in a new class of mixed-dimensional moiré materials.
Correlation and path analysis between main agronomic characters and per plant yield on Lotus corniculatus Cui Yafei, Gansu Agricultural University, Lanzhou(China),College of Prataculture; Cao Zhizhong, Gansu Agricultural University, Lanzhou(China),College of Prataculture; Ma Leyuan, Gansu Agricultural University, Lanzhou(China),College of Prataculture
Gansu nong ye da xue xue bao,
20/Aug., Volume:
44, Issue:
4
Journal Article
对百脉根单株的11个农艺性状的相关分析，结果表明：分枝长度（X2）、分枝节间数（X3）、分枝茎粗（X｜）、侧枝数（墨）、侧枝长度（X7）、侧枝节间数（X8）、侧枝茎粗（X9）对单株产量（Y）的作用达到极显著水平，分枝数（X1）、自然高度（X11）与单株产量的相关性达到显著水平，而分枝叶柄长度（X5）、侧枝叶柄长度（X10）则与产量的相关性不显著．通径分析结果表明：各性状对产量的直接效应从大到小依次为：分枝长度（1．1216）〉分枝节间数（0．3463）〉侧枝长度（0．1146）〉分枝数（0．1064）〉分枝茎粗（0．0846）〉侧枝节间数（0．0342）〉侧枝茎粗（0．0289）〉侧枝数（0．0216）〉侧枝叶柄长度（-0．0436）〉分枝叶柄长度（-0．0654）〉自然高度（-0．7482）．著者文摘
The correlation and path analysis of 11 agronomic characters were studied with per plant in Lotus corniculatus. The results showed that yield （Y） of per plant was extremely significant affected by branch length（X2 ）, branch nodes （X3）, branch stem diameter （X4）, the number of sub-branches （Xs）, subbranch length（X7 ）, sub-branch nodes（X8 ） and sub-branch stem diameter（X9 ）, and significantly affected by the number of branches（X1 ） and natural height（X11 ）. However, no noticeable correlation was found between yield （Y） of per plant and branch leaf stalk（X5）,length of sub-branch leaf stalk（X10）. The result of path analysis indicated that the direct effect of e
Agronomic traits and plant type structure of erected crown vetch strain Ma Leyuan, Gansu Agricultural University, Lanzhou(China), College of Pratacultrue; Cao Zhizhong, Gansu Agricultural University, Lanzhou(China), College of Pratacultrue; Cui Yafei, Gansu Agricultural University, Lanzhou(China), College of Pratacultrue
Gansu nong ye da xue xue bao,
20/Jun., Volume:
44, Issue:
3
Journal Article
对‘绿宝石’小冠花和从‘绿宝石’中选育的直立型小冠花品系在景泰的生长表现以及主要性状指标进行了比较和分析。结果表明：与‘绿宝石’小冠花相比，直立型小冠花品系有更长的青绿期，株高、生长速度及鲜草产量均大于‘绿宝石’，但茎／叶、鲜／干间无差异。通过对株高以及株型结构的分析，发现直立型小冠花品系（b=10079）具有比‘绿宝石’（b=0.1802）更合理的生产结构。著者文摘
A comparison ...of the performances was made between crown vetch （Coronilla varia cv. ＇Lvbaoshi＇） and the erected Crown vetch strain selected and bred from the former. The results showed that the erected strain had a longer green-time and plant height. The growth speed was faster than Lvbaoshi. No significant difference was found between the stem-leaf ratio and the fresh-dry ratio. The erected strain had more reasonable spatial distribution of biomass （b= 1. 007 9） than that in Lvbaoshi （b=0. 180 2）.
Crosstalk is one of the greatest concerns in design of integrated high-density circuits since it could cause a wireless communication system serious deviating from its designed performance, ...especially in high frequency range case. This article studies the relationship between orientation and crosstalk between dual stripline. By analyzing the crosstalk effects in frequency and time domain, we find that the near-end crosstalk signals reduce and the far-end crosstalk increase as the orientation between dual stripline being changed from 0 to 90 degrees. This result provides a useful basis for design of integrated high-density circuits to get a trade-off between minimizing crosstalk and setting orientation between dual stripline.
A novel and practical transmission scheme called degree distribution & reliability based (DD&R) LDPC-COFDM is proposed for irregular LDPC coded OFDM (LDPC-COFDM) system. Unequal protection of ...irregular LDPC codes and sub carriers' reliability of OFDM are investigated and combined to enhance the transmission power efficiency. SNR of sub carriers is linearly quantized and defined as reliability. For the irregular LDPC block bits with higher degrees play more important role in the decoding process and hence need more protection during transmission. In the scheme, these important bits (with large degrees) are prior to be mapped to the sub carriers with higher reliabilities (SNR) in the Is' transmission. When reception fails and repeat is needed, the bits carried on the less reliable sub carriers will be in high retransmission priority since it's more likely to be error. Gaussian approximation (GA) scheme is employed to analyze asymptotic performance of the new scheme and some initial simulations are also considered. Both of the results reveal significant improvement compared with conventional method.
S-value and the single-event specific energy distribution for electrons are important quantities of the microdosimetry for understanding biological effects of ionizing radiation, both of which have ...close relation to other quantities of the microdosimetry. In this paper, these quantities of electrons were calculated by different codes from cell surface to nucleus or the whole cell. The properties of the low-energy electrons, such as δ particle equilibrium and the energy-loss straggling, were applied to Monte Carlo simulation codes including MOCA15, TRAX and Geant4, and these codes tracked the electrons until their energy was lower than our cutoff energy. The results of S-value and the single-event specific energy distribution in cell were compared to the results of the Penelope and MIRD.
User cooperation is employed to explore the inherent distributed spatial diversity priority of wireless network. Nodes based rather than linked based protocol is employed and the broadcast nature of ...radio network is considered by user cooperation. However cooperative partner selection might be difficult especially for nomadic cooperative networks as it requires partner's additional power consumption and it's generally quite limited due to battery size. Therefore partner selection metric should be carefully designed to meet high system power efficiency (SPE) that takes both source and partners power consumption into account. As the transmission power of the source is supposed to be fixed, high SPE requires minimal partner's forwarding power for certain reception performance. In this paper a novel retransmission partner selection method for cooperative HARQ is proposed to meet high SPE, which requires the forwarding power consumption for certain received SNR as small as possible. After the reception of 1st transmission fails, a SNR based region selection method is employed to choose the proper forwarding partner. Partners with different distance from destination would use different transmission power to ensure the reliable reception at the destination and the one with minimal forwarding power will be selected to improve SPE. As the partner moves towards the destination the required forwarding power for certain FER performance could be reduced. However, if it were too far from the source the received SNR would be less than the sensitivity and the partner isn't able to recognize the message needs forwarding. The tradeoff between system performance and forwarding power is studied and the preferred partner is suggested by simulation for high SPE.
PDF
