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PHOSPHORyl PROMOTION EFFECT AND FORMATION OF BOTH PEPTIDES AND NUClEOTIDES

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Chinese Chemical letters 1995年第3期6卷 209-210页

作者： Ju, y Zhou, WH zhao, yF Tsing Hua Univ Dept Chem Bioorgan Phosphorus Chem Lab Beijing 100084 Peoples R China

In the presence of phosphoryl group, N-(O,O-diisopropyl) phosphoryl threonine reacted with nucleosides to give both nucleotides and peptides. The result might give some clue to the prebiotic formation of nucleic acids...

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基于改进yOlOv7的微生物细胞识别算法

现代电子技术 2025年第01期48卷 47-54页

作者：吕彦朋赵颖彤苏晓明刘占英内蒙古自治区发酵产业节能减排工程技术研究中心生物发酵绿色制造内蒙古自治区工程研究中心内蒙古工业大学数据科学与应用学院

针对传统及人工方法识别多种类、大量微生物细胞存在耗时长、准确率低等问题，文中提出一种改进yOlOv7的微生物细胞识别算法yOlOv7-PN。通过引入改进的路径聚合网络（PANet）提取和融合不同尺度的特征，以捕捉细胞图像中的多尺度信息，... 详细信息

针对传统及人工方法识别多种类、大量微生物细胞存在耗时长、准确率低等问题，文中提出一种改进yOlOv7的微生物细胞识别算法yOlOv7-PN。通过引入改进的路径聚合网络（PANet）提取和融合不同尺度的特征，以捕捉细胞图像中的多尺度信息，从而提高细胞的检测精度和鲁棒性；在骨干网络添加注意力模块（NAM），能够自适应地学习每个通道的权重，提高细胞的特征表示能力；将传统的IoU边界框损失函数替换为DIoU＿loss，以考虑边界框之间的距离和重叠程度，能够更准确地衡量检测框的精度，从而提高细胞的定位准确性。实验结果表明，使用BCCD数据集进行评估时，文中算法在微生物细胞识别任务中取得了显著的提升，与基准算法yOlOv7相比，yOlOv7-PN的Precision值提高了1.46%、F1值提高了2.61%、Accuracy值提高了0.86%。实验结果验证了该算法的有效性和性能优势，为微生物学研究和医学诊断等领域的微生物细胞分析提供了有力支持。

关键词：微生物细胞 yOlOv7 yOlOv7-PN PANet NAM DIoU_loss

Exact solution of the one-dimensional Klein-Gordon equation with scalar and vector linear potentials in the presence of a minimal length

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Chinese Physics B 2010年第2期19卷 43-47页

作者： y Chargui l Chetouani A Trabelsi Unit de Recherche de Physique Nuclaire et des Hautes Energies Facult des Sciences de Tunis Dpartement de Physique Thorique Institut de PhysiqueUniversit de ConstantineRoute Ain El BeyConstantineAlgeria Centre National des Sciences et Technologies Nuclaires Technopole de Sidi-Thabet 2020Tunisia

Using the momentum space representation, we solve the Klein--Gordon equation in one spatial dimension for the case of mixed scalar and vector linear potentials in the context of deformed quantum mechanics characterized by a finite minimal uncertainty in position. The expressions of bound state energies and the associated wave functions are exactly obtained.

关键词： Klein--Gordon equation linear potential minimal length exact solution

GRID GENERATION AND NUMERICAl SIMUlATION OF 2-D RIVER FlOW

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Journal of Hydrodynamics 2001年第2期13卷 50-54页

作者： zhao, M.D. li, y.T. Dept. of River Eng. Wuhan Univ. Wuhan 430072 China

This paper presents new weighting functions in grid generation and new discretizing scheme of momentum equations in numerical simulation of river flow. By using the new weighting functions, the curvilinear grid could be concentrated as desired near the assigned points or lines in physical plane. By using the new discretizing scheme, the difficulties caused by movable boundary and dry riverbed can be overcome. As an application, the flow in the Wuhan Section of yangtze River is simulated. The computational results are in good agreement with the measured results. The new method is applicable to the numerical simulation of 2-D river flow with irregular region and moveable boundary.

关键词： Computer simulation Flow of fluids Mathematical models Poisson equation Two dimensional

Robust Optimal Framework for Doubly Fed Induction Generator with Uncertain Dynamics

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Protection and Control of Modern Power Systems 2024年第5期9卷 129-141页

作者： yongfeng lü Xiaowei zhao Priyank Shah College of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan 030024China Intelligent Control and Smart Energy(ICSE)Research Group School of EngineeringThe University of WarwickCoventry CV47ALUK

A robust optimal framework is designed herein to mitigate the oscillatory dynamics in a doubly fed induction generator(DFIG)even in the presence of network disturbances and input *** address uncertain dynamics,herein,a novel transformation formula is developed for a wind energy conversion *** unscented Kalman filter is applied to estimate the un-measured internal states of the wind energy conversion system using terminal *** detailed convergence and stability analyses of the presented framework are investigated to validate its ***,comparative modal analyses are carried out to demonstrate the improvement in the damping of critical low-frequency oscillatory modes using the presented *** simulation results demonstrate satisfactory performance under various operating scenarios,such as increasing and decreasing wind speed and varying the terminal *** comparative performance is demonstrated to validate the effectiveness of the presented framework over that of the state-of-the-art frameworks.

关键词： Optimal control power system renew-able energy sources wind energy conversion system doubly fed induction generator

Contribution of Root Respiration to Total Soil Respiration in a Cotton Field of Northwest China

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Pedosphere 2013年第2期23卷 223-228页

作者： zhao Zhi-Min zhao Cheng-yi y.yIlIHAMU lI Ju-yan lI Jun State Key laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences University of Chinese Academy of Sciences

To measure the contribution of root respiration (Rr) to total soil respiration (Rt) in arid cotton fields, eighteen plots, nine for girdling and nine control, were built in an arid cotton field in the Aksu National Experimental Station of Oasis Farmland Ecosystem, Xinjiang of China. Given the difference of soil respiration between girdled plots and non-girdled control plots, the components of soil respiration, root respiration (Rr) and respiration originating from decomposition (Rd) were divided. The temperature sensitivities of R r and R d were analyzed, respectively. The results showed that the average contribution of R r to R t in arid cotton field was about 32% during the study period. The temperature-response curve of R r differed from that of Rd . The dynamic variation of R d was more related to the change of soil temperature as compared to Rr . Rr and Rd had different responses to the variation of environment, and thus new models capable of differentiating between Rr and Rd are needed for evaluating the different factors controlling these two components of soil respiration in arid cotton field.

关键词： abiotic factor decomposition girdling phenological phase temperature response value

Number of states with given spin I and isospin T for n fermions in a j orbit

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Chinese Physics C 2022年第11期46卷 195-202页

作者： X.yin y.M.zhao Shanghai Key laboratory of Particle Physics and Cosmology School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA(CICIFSA) Shanghai Jiao Tong UniversityShanghai 200240China

In this study,we investigate formulas of the number of states with a given total spin I and isospin T for n nucleons in a single-j shell denoted by DIT(j,n).Talmi's recursion formulas for the number of states with a given z-axis projection of total spin are generalized by further considering the isospin couplings and are applied to derive explicit formulas of DIT(j,n).

关键词： nuclear structure shell model nuclear spin and isospin

Frequency equations of nonlocal elastic micro/nanobeams with the consideration of the surface effects

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Applied Mathematics and Mechanics(English Edition) 2018年第8期39卷 1089-1102页

作者： H.S.zhao y.ZHANG S.T.lIE School of Civil and Environmental Engineering Nanyang Technological University

A nonlocal elastic micro/nanobeam is theoretically modeled with the consideration of the surface elasticity, the residual surface stress, and the rotatory inertia,in which the nonlocal and surface effects are considered. Three types of boundary conditions, i.e., hinged-hinged, clamped-clamped, and clamped-hinged ends, are examined. For a hinged-hinged beam, an exact and explicit natural frequency equation is derived based on the established mathematical model. The Fredholm integral equation is adopted to deduce the approximate fundamental frequency equations for the clamped-clamped and clamped-hinged beams. In sum, the explicit frequency equations for the micro/nanobeam under three types of boundary conditions are proposed to reveal the dependence of the natural frequency on the effects of the nonlocal elasticity, the surface elasticity, the residual surface stress, and the rotatory inertia, providing a more convenient means in comparison with numerical computations.

关键词： Fredholm integral equation micro/nanobeam natural frequency nonlocal elasticity surface effect

low Temperature Synthesis of Diamond Films by CVD of Combined lasers

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Journal of Materials Science & Technology 1998年第1期14卷 80-82页

作者： Feng, ZC zhao, y Zhang, BC Wang, yQ Wu, ZG Chinese Acad Sci Inst Met Res Shenyang 110015 Peoples R China

Diamond films have been synthesized by means of lCVD through combined effects of a XeCl ultraviolet laser and an infrared CO2 laser. A special apparatus has been developed. The conditions of synthesis and the roles pl... 详细信息

关键词： Diamond films