抗寒优质苹果新品种──蒙富、蒙光

抗寒优质苹果新品种──蒙富、蒙光李向宏，乔凤岐，丛日春，李怀玉（内蒙古赤峰市松山区林业局０２４００５）（宁城县巴林果树试验场）（沈阳农业大学）１选育经过蒙富原代号７８—７—２７２，蒙光原代号７８—１—２２，是１９７８年选用抗寒性强、果味酸的大苹果东光...

抗寒优质苹果新品种——蒙富、蒙光

蒙富是以东光为母本,富士为父本;蒙光是以东光为母本,胜利为父本杂交育成。在内蒙宁城县年平均气温6.7℃,一月份平均气温-12.5℃,绝对最低温度-32.7℃的地区栽植能安全自然越冬。蒙富是短枝型品种。两个品种表现抗寒性强,结果早,果实大,优质丰产,成熟期早,耐贮藏。1995年2月通过内蒙古自治区农作物品种审定委员会审定并命名。目前在"三北"地区已推广1400余公倾。

Effects of tissue absorption on calculation of mean photon path length using modified Beer-Lambert law

The mean path length(MPL)of photons is a critical parameter to calculate tissue absorption coefficient as well as blood oxygenation using modified Beer-Lambert law,where in the differential path factor(DPF)is often assumed as constant over range of tissue absorption.By utilizing the Monte Carlo(MC)simulation of photon migrations in the leg,this study used four approaches to estimate MPL,and compared them with that determined by the MPL definition.The simulation results indicate that the DPF is remarkably affected by tissue absorption,at approximate 10% variation.A linear model is suggested to calculate MPL for measurements of tissue absorption as well as blood oxygenation using modified Beer-Lambert law.

Monte Carlo Simulation of Impurity Scattering Effect in Resonant-Phonon-Assisted Terahertz Quantum-Cascade Lasers

We study the influence of ionized impurity scattering on the electron transport in resonant-phonon-assisted terahertz （THz） quantum-cascade lasers （QCLs）. We treat the ionized impurity scattering rates within the single subband static screening approximation. We find that the ionized impurity scattering supplies an additional current channel across the device,and affects the electrondistribution in different subbands. We conclude that the ionized impurity scattering should be taken into account in the study of the transport properties of resonant-phonon-assisted THz QCLs.

Comparison of GUF and Monte Carlo methods to evaluate task-specific uncertainty in laser tracker measurement

Measurement uncertainty plays an important role in laser tracking measurement analyses. In the present work, the guides to the expression of uncertainty in measurement(GUM) uncertainty framework(GUF) and its supplement, the Monte Carlo method, were used to estimate the uncertainty of task-specific laser tracker measurements. First, the sources of error in laser tracker measurement were analyzed in detail, including instruments, measuring network fusion, measurement strategies, measurement process factors(such as the operator), measurement environment, and task-specific data processing. Second, the GUM and Monte Carlo methods and their application to laser tracker measurement were presented. Finally, a case study involving the uncertainty estimation of a cylindricity measurement process using the GUF and Monte Carlo methods was illustrated. The expanded uncertainty results(at 95% confidence levels) obtained with the Monte Carlo method are 0.069 mm(least-squares criterion) and 0.062 mm(minimum zone criterion), respectively, while with the GUM uncertainty framework, none but the result of least-squares criterion can be got, which is 0.071 mm. Thus, the GUM uncertainty framework slightly underestimates the overall uncertainty by 10%. The results demonstrate that the two methods have different characteristics in task-specific uncertainty evaluations of laser tracker measurements. The results indicate that the Monte Carlo method is a practical tool for applying the principle of propagation of distributions and does not depend on the assumptions and limitations required by the law of propagation of uncertainties(GUF). These features of the Monte Carlo method reduce the risk of an unreliable measurement of uncertainty estimation, particularly in cases of complicated measurement models, without the need to evaluate partial derivatives. In addition, the impact of sampling strategy and evaluation method on the uncertainty of the measurement results can also be taken into account with Monte Carlo method, which plays a guiding role in measurement planning.

Verification of Net Primary Production Estimation Method in the Mongolian Plateau Using Landsat ETM+ Data

We plan to estimate global net primary production (NPP) of vegetation using the Advanced Earth Observing Satellite\|Ⅱ (ADEOS\|Ⅱ) Global Imager (GLI) multi\|spectral data. We derive an NPP estimation algorithm from ground measurement data on temperate plants in Japan. By the algorithm, we estimate NPP using a vegetation index based on pattern decomposition (VIPD) for the Mongolian Plateau. The VIPD is derived from Landsat ETM+ multi\|spectral data, and the resulting NPP estimation is compared with ground data measured in a semi\|arid area of Mongolia. The NPP estimation derived from satellite remote sensing data agrees with the ground measurement data within the error range of 15% when all above\|ground vegetation NPP is calculated for different vegetation classifications.

Monte Carlo study of spatial resolution of the scintillation camera

The aim of this study was to evaluate the influence of different entrance surface treatments of the scintillator on the intrinsic spatial resolution of a scintillation camera.The primary scintillation light reflection on the entrance surface of a scintillator may be affected by the optical coating of the entrance surface,resulting in either spatial resolution or system detection efficiency degradation.A Monte Carlo simulation model,based on Geant4 codes,was developed in order to study the scintillation light transportation in the scintillator with an entrance surface of various optical coatings.The results demonstrated that the application of retro-reflector on entrance surface of the scintillation crystal can significantly improve the intrinsic spatial resolution of the scintillation camera.The physical mechanism of the improvement of spatial resolution is explored.

Performance analyses of subcarrier BPSK modulation over M turbulence channels with pointing errors

An aggregated channel model is achieved by fitting the Weibull distribution, which includes the effects of atmospheric attenuation, M distributed atmospheric turbulence and nonzero boresight pointing errors. With this approximate channel model, the bit error rate （BER） and the ergodic capacity of free-space optical （FSO） communication systems utilizing sub- cartier binary phase-shift keying （BPSK） modulation are analyzed, respectively. A closed-form expression of BER is de- rived by using the generalized Gauss-Lagueree quadrature rule, and the bounds of ergodic capacity are discussed. Monte Carlo simulation is provided to confirm the validity of the BER expressions and the bounds of ergodic capacity.

TMT tertiary mirror axis calibration with laser tracker

To calibrate the tracing performance of the thirty meter telescope （TMT） tertiary mirror, for the special requirement of the TMT, the laser tracker is used to verify the motion. Firstly, the deviation is divided into two parts, namely, the re- peatable error and the unrepeatable part. Then, based on the laser tracker, the mearturement and evalutation methods of the rigid body motion for the mirror are established, and the Monte Carol method is used to determine the accuracy of the mothod. Lastly, the mothod is applied to the turn table of a classical telescope and the residual error is about 4 arc second. The work of this paper will guide the next desgin and construction work of the thirty meter telescope tertiary

Bi2WO6 quantum dot-intercalated ultrathin montmo- rillonite nanostructure and its enhanced photocatalytic performance

The kinetic competition between electron-hole recombination and water oxidation is a key limitation for the development of efficient solar water splitting materials. In this study, we present a solution for solving this challenge by constructing a quantum dot-intercalated nanostructure. For the first time, we show the interlayer charge of the intercalated nanostructure can significantly inhibit the electron-hole recombination in photocatalysis. For Bi2WO6 quantum dots （QDs） intercalated in a montmorillonite （MMT） nanostructure as an example, the average lifetime of the photogenerated charge carriers was increased from 3.06 μs to 18.8 Ds by constructing the intercalated nanostructure. The increased lifetime markedly improved the photocatalytic performance of Bi2WO6 both in solar water oxidation and environmental purification. This work not oMy provides a method to produce QD-intercalated ultrathin nanostructures but also a general route to design efficient semiconductor-based photoconversion materials for solar fuel generation and environmental purification.

What makes the Tc of monolayer FeSe on SrTiO3 so high： a sign-problem-free quantum Monte Carlo study

Monolayer FeSe films grown on SrTiO_3(STO)substrate show superconducting gap-opening temperatures(T_c) which are almost an order of magnitude higher than those of the bulk FeSe and are highest among all known Fe-based superconductors. Angle-resolved photoemission spectroscopy observed ‘‘replica bands' ' suggesting the importance of the interaction between FeSe electrons and STO phonons. These facts rejuvenated the quest for T_c enhancement mechanisms in iron-based, especially ironchalcogenide, superconductors. Here, we perform the first numerically-exact sign-problem-free quantum Monte Carlo simulations to iron-based superconductors. We(1) study the electronic pairing mechanism intrinsic to heavily electron doped FeSe films, and(2) examine the effects of electron–phonon interaction between FeSe and STO as well as nematic fluctuations on T_c. Armed with these results, we return to the question ‘‘what makes the Tcof monolayer FeSe on SrTiO_3 so high?'' in the conclusion and discussions.