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Genetic Improvement of Root Growth Contributes to Efficient Phosphorus Acquisition in maize (Zea mays L.)

Journal of Integrative Agriculture 2013年第6期12卷 1098-1111页

作者： ZHANG yi-kai CHEN Fan-jun CHEN Xiao-chao LONG Li-zhi GAO Kun YUAN Li-xing ZHANG Fu-suo MI Guo-hua Laboratory of Plant-Soil Interactions Ministry of Education/Center for Resources Environment and Food Security College of Resources and Environmental Science China Agricultural University

Maize plants adapt to low phosphorus （P） stress by increasing root growth. It is of importance to know the extent to which genetic improvement of root growth can enhance P acquisiton. In the present study, the contribution of root growth improvement to efficient P acquisition was evaluated in two soils using T149 and T222, a pair of near isogenic maize testcrosses which were derived from a backcross BC 4 F 3 population. T149 and T222 showed no difference in shoot biomass and leaf area under normal growth conditions, but differed greatly in root growth. T149 had longer lateral roots and a larger root surface area compared to T222. In calcareous soil, when P was insufficient, i.e., when P was either supplied as KH 2 PO 4 at a concentration of 50 mg P kg-1 soil, or in the form of Phy-P, Ca3-P or Ca10-P, a 43% increase in root length in T149 compared to T222 resulted in an increase in P uptake by 53%, and shoot biomass by 48%. In acid soil, however, when P supply was insufficient, i.e., when P was supplied as KH 2 PO 4 at a concentration of 100 mg P kg-1 soil, or in the form of Phy-P, Fe-P or Al-P, a 32% increase in root length in T149 compared to T222 resulted in an increase in P uptake by only 12%, and shoot biomass by 7%. No significant differences in the exudation of organic acids and APase activity were found between the two genotypes. It is concluded that genetic improvement of root growth can efficiently increase P acquisition in calcareous soils. In acid soils, however, improvements in the physiological traits of roots, in addition to their size, seem to be required for efficient P acquisition.

关键词： P efficiency roots low phosphorus calcareous soil acid soil maize

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MALDI-TOF MS验证与综合评价

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中国口岸科学技术 2024年第8期6卷 18-27页

作者：王艺凯侯颖杨帆任宇捷杨菲李运涛邱烨刘鑫中国海关科学技术研究中心北京100026 二连海关技术中心二连浩特011100 北京融智优普生物科技有限公司北京100026

基质辅助激光解吸电离飞行时间质谱(Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry,MALDI-TOF MS)在微生物鉴定方面具有快速高通量分析和高灵敏度等优点,被广泛应用于医疗诊断、生物防御、环境监测和... 详细信息

基质辅助激光解吸电离飞行时间质谱(Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry,MALDI-TOF MS)在微生物鉴定方面具有快速高通量分析和高灵敏度等优点,被广泛应用于医疗诊断、生物防御、环境监测和食品质量控制等相关领域。MALDI-TOF MS与PCR技术结合,能够实现高通量的核苷酸位点分析。为了确保其在应用中的可靠性和准确性,建立一套完善的验证与综合评价方案对其进行性能评价至关重要。本文通过参考现有MALDI-TOF MS标准并结合核酸检测的特殊性,建立了该类型设备的验评方案,提出了包含质量测定范围、准确性、分辨率、稳定性等基本性能验证指标和准确性、灵敏度、重复性、抗干扰性等应用性能验证技术指标。依据以上指标,对QuanNUA型MALDI-TOF MS进行验评,验评方案方便易行且无须专业的计量设备,普通的分子生物学实验室就能够对MALDI-TOF MS进行系统和全面验评。该验评方案可为MALDI-TOF MS用于核酸鉴定性能评价提供参考。

关键词：基质辅助激光解吸电离飞行时间质谱性能评价核酸检测

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Crystal phase control and ignition properties of HNS/CL-20 composite microspheres prepared by microfluidics combined with emulsification techniques

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Particuology 2024年第2期85卷 241-251页

作者： yi Liu Yunyan Guo Rui Zhu Jinqiang Zhou Zhengxu Lin kai Han Chongwei An Jingyu Wang Bidong Wu School of Environment and Safety Engineering North University of ChinaTaiyuan030051China School of Engineering Beijing Institute of TechnologyBeijing100081China Shanxi Province Ultrafine Powder Engineering Technology Research Center Taiyuan030051China

Improved controllability and energy density of ignition agents are of great significance for the devel-opment of energetic composite *** this study,droplet microfluidics and emulsification tech-niques were combined to prepare HNS/CL-20 composite microspheres with polyglycidyl azide polymer(GAP)as the *** influence of binder content on the morphology of microspheres was investi-gated,and the microspheres were characterized and tested for particle size,crystal structure,thermal decomposition,dispersibility,mechanical sensitivity,combustion behavior and detonation *** results showed that microspheres prepared with a binder content of 3%had higher sphericity and particle size *** microspheres retained the crystal structure of both HNS and CL-20(ε-type).Compared with raw HNS,the microspheres had higher apparent activation energy,better safety per-formance,and good *** ignition experiments and detonation performance tests show that HNS/CL-20 composite microspheres have excellent ignition performance,obvious combustion flame,and significant energy release effects,which are expected to achieve high energy and high-speed response of the igniter,thus improving the ignition reliability in special environments or systems.

关键词： Droplet microfluidics Emulsification technology Energetic materials Composite microspheres Crystal phase control Ignition

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Study on a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding

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Advances in Manufacturing 2024年第2期12卷 288-299页

作者： Zhao-Qing Zhang kai-Ning Shi Yao-Yao Shi yi-Hui Song Zhe He Ya-Song Pu School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an710072People’s Republic of China Key Laboratory of High Performance Manufacturing for Aero Engine(Northwestern Polytechnical University) Ministry of Industry and Information TechnologyXi’an710072People’s Republic of China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine(Northwestern Polytechnical University) Ministry of EducationXi’an710072People’s Republic of China

Profile grinding is the most crucial method for the ultra-precision machining of special-shaped ***,profile grinding produces a unique machining profile,and many random factors in the machining process lead to complex surface *** this study,the structural and probabilistic characteristics of the profile grinding of a special-shaped surface were analyzed,and a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding was *** forming process of a GH738 blade tenon tooth surface was considered as an example to demonstrate the *** comparison results showed that the simulation results had similar surface characteristics to the measurement results,and the relative error range of the 3D roughness parameter was 0.21%–19.76%,indicating an accurate prediction and characterization of the complex special-shaped surface under the action of multiple factors.

关键词： Special-shaped surface Profile grinding Surface morphology 3D characterization

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Exploring charge and spin fluctuations in infinite-layer cuprate SrCuO_(2)from a phonon perspective

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 159-167页

作者： Xin Du Pei-Han Sun Ben-Chao Gong Jian-Feng Zhang Zhong-yi Lu kai Liu Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China Department of Physics School of ScienceJiangsu University of Science and TechnologyZhenjiang 212100China Institute of Physics Chinese Academy of SciencesBeijing 100190China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China

The infinite-layer cuprate ACu O_(2)(A=Ca,Sr,Ba)possesses the simplest crystal structure among numerous cuprate superconductors and can serve as a prototypical system to explore the unconventional *** on the first-principles electronic structure calculations,we have studied the electronic and magnetic properties of the infinite-layer cuprate SrCuO_(2)from a phonon *** find that interesting fluctuations of charges,electrical dipoles,and local magnetic moments can be induced by the atomic displacements of phonon modes in SrCuO_(2)upon the hole *** all optical phonon modes of SrCuO_(2)in the antiferromagnetic Néel state,only the A_(1g)mode that involves the full-breathing O vibrations along the Cu-O bonds can cause significant fluctuations of local magnetic moments on O atoms and dramatic charge redistributions between Cu and O ***,due to the atomic displacements of the A_(1g)mode,both the charge fluctuations on Cu and the electrical dipoles on O show a dome-like evolution with increasing hole doping,quite similar to the experimentally observed behavior of the superconducting T_(c);in comparison,the fluctuations of local magnetic moments on O display a monotonic enhancement along with the hole *** analyses indicate that around the optimal doping,there exists a large softening in the frequency of the A_(1g)phonon mode and a van Hove singularity in the electronic structure close to the Fermi level,suggesting potential electron-phonon *** work reveals the important role of the full-breathing O phonon mode playing in the infinite-layer SrCuO_(2),which may provide new insights in understanding the cuprate superconductivity.

关键词： first-principles calculations cuprate superconductors phonon charge and spin fluctuations

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6DOF pose estimation of a 3D rigid object based on edge-enhanced point pair features

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Computational Visual Media 2024年第1期10卷 61-77页

作者： Chenyi Liu Fei Chen Lu Deng Renjiao yi Lintao Zheng Chenyang Zhu Jia Wang kai Xu College of Computing National University of Defense TechnologyChangsha410073China Department of Spine Surgery the Second Xiangya HospitalCentral South UniversityChangsha410011China Clinical Nursing Teaching and Research Section the Second Xiangya HospitalChangsha410011China College of Meteorology and Oceanography National University of Defense TechnologyChangsha410073China Beijing Institute of Tracking and Communication Technology Beijing100094China

The point pair feature(PPF)is widely used for 6D pose *** this paper,we propose an efficient 6D pose estimation method based on the PPF *** introduce a well-targeted down-sampling strategy that focuses on edge areas for efficient feature extraction for complex geometry.A pose hypothesis validation approach is proposed to resolve ambiguity due to symmetry by calculating the edge matching *** perform evaluations on two challenging datasets and one real-world collected dataset,demonstrating the superiority of our method for pose estimation for geometrically complex,occluded,symmetrical *** further validate our method by applying it to simulated punctures.

关键词： point pair feature(PPF) pose estimation object recognition 3D point cloud

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Differential bonding behaviors of sodium/potassium-ion storage in sawdust waste carbon derivatives

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Chinese Chemical Letters 2024年第4期35卷 496-501页

作者： Jun-Ming Cao kai-Yang Zhang Jia-Lin Yang Zhen-yi Gu Xing-Long Wu MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchun 130024China Department of Chemistry Northeast Normal UniversityChangchun 130024China

Sodium-ion batteries(SIBs) and potassium-ion batteries(PIBs) are the most promising alternatives to lithium-ion batteries, and thus have drawn intensive research attention. Porous carbon materials from different precursors have been widely used as anode materials owing to their compatible storage effectiveness of both larger radii sodium and potassium ions. However, the differential bonding behaviors of Na and K ions with porous carbon-based anode are the significant one worth investigating, which could provide a clean picture of alkali ions storage mechanism. Therefore, in this work, we prepare a porous carbon network derived from sawdust(SDC) wastes, to further analyze the differences on sodium and potassium ions storage behaviors in terms of bond-forming process. It is found that, as-prepared SDC anodes could deliver stable sodium and potassium storage capacities, however, there are notable distinctions in terms of electrochemical behaviors and diffusion processes. By virtue of ex-situ XRD and Raman spectroscopy, the phase transition reaction of potassium ions could be well-observed, and the results shows that the multiple intercalated compounds was formed in SDC network during ions insertion, further resulting in slower diffusion kinetics and larger resistance compared to non-bonded process of sodium ions storage. This study provides more insights into the differences between sodium and potassium ions storage, as well as the energy storage mechanism of porous carbon as anodes for secondary batteries.

关键词： Porous carbon Sodium-ion storage Potassium-ion storage Bonding behaviors Batteries

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按摩理疗机器人应用现状及展望

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中国医疗器械信息 2024年第1期30卷 83-86,174页

作者：刘志龙杜加军李俊桦陈超李义凯深圳市灵手科技有限公司广东深圳518000 南方医科大学中医药学院广东广州510515 南方医科大学第三附属医院中医骨伤科广东广州510630

传统中医理疗过度依赖人工的特性使其面临专业医师稀缺、人工成本高等问题,按摩理疗机器人应运而生。文章概述国内外具有代表性的几款按摩理疗机器人的功能特点,分析国内按摩理疗机器人行业现阶段存在的问题,并展望按摩理疗机器人的发展... 详细信息

传统中医理疗过度依赖人工的特性使其面临专业医师稀缺、人工成本高等问题,按摩理疗机器人应运而生。文章概述国内外具有代表性的几款按摩理疗机器人的功能特点,分析国内按摩理疗机器人行业现阶段存在的问题,并展望按摩理疗机器人的发展,以期为本行业的发展提供一定的参考思路。

关键词：按摩机器人理疗机器人中医推拿研究现状

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Shaly detritus embedded epoxy-resin coated proppants

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Petroleum Science 2022年第4期19卷 1735-1744页

作者： Zhao-Hui Lu Xiu-Ping Lan Yong Yuan Jian-Kun Zhou Si-Yuan Chen Fan Fan ying-Chun Niu Shou-Zhen Li kai-yi Hu Yang Zhou Quan Xu Key Laboratory of Shale Gas Exploration Ministry of Natural ResourcesChongqing Institute of Geology and Mineral ResourcesChongqing401120China State Key Laboratory of Petroleum Resources and Prospecting Bejing Key Laboratory of Biogas Upgrading UtlizationHarvard SEAS-CUPB Joint Laboratory on Petroleum ScienceChina University of Petroleum(Beijing)Beijing102249China

Proppant plays a significant role in the hydraulic fracturing process, which can affect the production of oil and gas wells. Due to the high density and low adhesion force, the settling speed of traditional proppants is fast, which will lead to the blockage of a crack channel. In this study, a proppant with double layer structure is fabricated by coating epoxy-resin and shaly detritus on ceramic proppants for the first time,respectively. The epoxy-resin enables the shaly detritus to be coated on the proppant successfully, which can provide a new method for shaly detritus treatment. The adhesive ability of shaly detritus and epoxyresin coated proppants(SEPs) is improved by 10.4% under the load force of 500 n N, which prolongs the time for the fracture to close. At the same time, the suspending ability of SEPs is two times higher than the uncoated proppants. Once the guar gum solution concentration is 0.3 wt%, the settling time of SEPs is36.7% longer than that of the uncoated proppants, which can effectively reduce the settlement of proppants in the crack. In addition, the hydrophobicity of the SEPs is enhanced, which reduces the wateroil ratio of crude oil and increases the liquid conductivity tested by deionized water. In summary, this new proppant is expected to promote the development of unconventional oil and gas resources.

关键词： Coated proppant Shaly detritus Hydrophobicity Conductivity

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两带自适应FIR线性相位双正交滤波器组设计

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电子与信息学报 2006年第10期28卷 1950-1954页

作者：水冰史仪凯西北工业大学机电学院西安710072

自适应滤波器组设计是多速率滤波器组理论和应用的一个重要方面。由于其频率响应更好匹配于输入信号的统计特性,这类滤波器组可获得更大的子带编码增益。该文研究了两带自适应FIR线性相位双正交滤波器组的设计问题,给出了设计算法,特别... 详细信息

自适应滤波器组设计是多速率滤波器组理论和应用的一个重要方面。由于其频率响应更好匹配于输入信号的统计特性,这类滤波器组可获得更大的子带编码增益。该文研究了两带自适应FIR线性相位双正交滤波器组的设计问题,给出了设计算法,特别是通过最优IIR双正交滤波器组确定初始点(初始滤波器组)的方法。仿真结果表明,得到的滤波器组的子带编码增益远远超过了最优的IIR正交滤波器组,与已有的设计结果比较,编码增益明显提高。

关键词：主分量滤波器组子带编码增益线性相位最优IIR双正交滤波器组

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