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南疆地区复种早熟粮饲兼用玉米叶绿素荧光特征分析

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西南农业学报 2024年第6期37卷 1254-1265页

作者：张占琴杨相昆颉健辉田海燕桑志勤夏春兰新疆农垦科学院新疆石河子832000 谷物品质与遗传改良兵团重点实验室新疆石河子832000

【目的】为明确南疆地区复种早熟粮饲兼用玉米品种最佳种植密度以及不同密度下叶绿素荧光特征参数变化规律及其与产量形成的关系,为南疆地区复播玉米种植技术的提升提供参考依据。【方法】以自育早熟粮饲兼用玉米杂交新品种XL1822和XL1... 详细信息

【目的】为明确南疆地区复种早熟粮饲兼用玉米品种最佳种植密度以及不同密度下叶绿素荧光特征参数变化规律及其与产量形成的关系,为南疆地区复播玉米种植技术的提升提供参考依据。【方法】以自育早熟粮饲兼用玉米杂交新品种XL1822和XL1903为材料,设置高、低两种密度(9.00×10^(4)和11.25×10^(4)株/hm^(2)),研究两个玉米品种高、低密度下叶片叶绿素荧光特征参数、主要农艺性状、干物质积累及产量结构等的差异。【结果】XL1822低密度处理在拔节期、大喇叭口期、吐丝期、灌浆期叶片实际光量子产量[Y(Ⅱ)]、光化学淬灭系数(qL)、PSⅡ反应中心活性较高;XL1903高密度处理在拔节期、大喇叭口期、吐丝期叶片Y(Ⅱ)、qL较高。XL1822低密度处理在吐丝期、灌浆期、成熟期叶片SPAD值略高于高密度。XL1903高密度处理全生育期叶片的SPAD值较高。XL1822低密度籽率产量为9250 kg/hm^(2)、干物质积累量为15590 kg/hm^(2),显著高于高密度处理。XL1903高密度籽率产量为9065 kg/hm^(2)、干物质积累量为19095 kg/hm^(2),显著高于低密度处理。【结论】较高的叶绿素荧光特征参数和SAPD值为玉米产量形成和干物质积累奠定基础。极早熟品种XL1822低密度处理、早熟玉米品种XL1903高密度处理在关键生育时期植株Y(Ⅱ)、qL、PSⅡ反应中心活性较高,因此XL1822种植密度为9×10^(4)株/hm^(2),XL1903种植密度为11.25×10^(4)株/hm^(2)时在南疆地区可获得较高产量。

关键词：复种早熟极早熟叶绿素荧光特征粮饲兼用产量

Heterosis and heterotic patterns of maize germplasm revealed by a multiple-hybrid population under well-watered and drought-stressed conditions

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Journal of Integrative Agriculture 2022年第9期21卷 2477-2491页

作者： sang zhi-qin ZHANG Zhan-qin YANG Yu-xin LI zhi-wei LIU Xiao-gang XU Yun-bi LI Wei-hua Key Laboratory of Oasis Eco-Agriculture Xinjiang Production and Construction Corps/Agricultural CollegeShihezi UniversityShihezi 832003P.R.China Xinjiang Academy of Agricultural and Reclamation Science Shihezi 832000P.R.China Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081P.R.China International Maize and Wheat Improvement Center(CIMMYT) El Batan Texcoco 56130Mexico

Understanding the heterosis in multiple environments between different heterotic groups is of fundamental importance in successful maize breeding. A total of 737 hybrids derived from 41 maize inbreds were evaluated over two years, with the aim of assessing the genetic diversity and their performance between heterotic groups under drought-stressed(DS) and well-watered(WW) treatments. A total of 38 737 SNPs were employed to assess the genetic diversity. The genetic distance(GD) between the parents ranged from 0.05 to 0.74, and the 41 inbreds were classified into five heterotic groups. According to the hybrid performance(high yield and early maturity between heterotic groups), the heterosis and heterotic patterns of Iowa Stiff Stalk Synthetic(BSSS)×Non-Stiff Stalk(NSS), NSS×Sipingtou(SPT) and BSSS×SPT were identified to be useful options in China’s maize breeding. The relative importance of general and specific combining abilities(GCA and SCA) suggests the importance of the additive genetic effects for grain yield traits under the WW treatment, but the non-additive effects under the DS treatment. At least one of the parental lines with drought tolerance and a high GCA effect would be required to achieve the ideal hybrid performance under drought conditions. GD showed a positive correlation with yield and yield heterosis in within-group hybrids over a certain range of GD. The present investigation suggests that the heterosis is due to the combined accumulation of superior genes/alleles in parents and the optimal genetic distance between parents, and that yield heterosis under DS treatment was mainly determined by the non-additive effects.

关键词： maize drought stress heterosis heterotic group heterotic pattern genetic distance

Microstructure and mechanical properties of Ti/Al/Ti clad plates prepared via powder-in-tube method

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Journal of Iron and Steel Research International 2024年第3期31卷 670-687页

作者： Xian-lei Hu qin-cheng Xie Yi Yuan Ying zhi State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina Suzhou Dongbao Haixing Metal Material Technology Co. Ltd.Suzhou 215600JiangsuChina School of Material Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina

The Ti/Al/Ti clad plates exhibit a broad spectrum of potential ***,the conventional techniques of hot-pressing composite and explosive composite are intricate and environmentally hazardous.A novel method was introduced for preparing clad plates,namely,the powder-in-tube *** method involves a combination of cold rolling,annealing at a temperature of 550℃,and double *** morphology of the intermetallic compound layer was analyzed through the utilization of interface stripping test,tensile test,and microscopic *** interface morphology,interface bonding properties,tensile fracture structures,and properties of plates under the first and second rolling were compared,along with the effects of intermetallic compounds on the interface *** results indicate that the powder-in-tube method,when annealed at 550℃,can produce a composite plate featuring a complete and uniform Ti/Al *** obtained plate exhibits a peeling strength of 21.5 N/mm,tensile strength of 424 MPa,and elongation of 11.5%.Furthermore,a systematic analysis was conducted to determine the causes of performance degra-dation observed during annealing at temperatures of 600 and 650℃.

关键词： Powder-in-tube method-Ti/Al/Ti clad plate Annealing Cold rolling-Mechanical property

Magnetic emission intensity enhancement for amorphous alloys by constructing a multi-phase structure withα-Fe nanocrystals

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Nano Research 2024年第7期17卷 6630-6637页

作者： Ke Liu zhi qin Jie Shen zhi Cheng Shiyue You Liang Ma Jing Zhou Wen Chen State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Sanya Science and Education Innovation Park Wuhan University of TechnologySanya 572024China Hubei Longzhong Laboratory Wuhan University of Technology Xiangyang Demonstration ZoneXiangyang 441000China

The perturbation in the magnetic field generated by the rotation or oscillation of magnetic domains in magnetic materials can emit low-frequency electromagnetic waves,which are expected to be used in low-frequency ***,the magnetic emission intensity,defined by the perturbation ability,of current commercially applied amorphous alloys,such as Metglas,cannot meet the application requirements for low-frequency antennas due to the domain motion energy ***,a multi-phase Metglas amorphous alloy was constructed by incorporatingα-Fe nanocrystals using rapid annealing to manipulate the domain *** was found that 3.89 times higher magnetic emission intensity is obtained compared to the pristine due to the synergism of the deformation and displacement ***,the low-frequency magnetic emission performance verification was carried out by preparing magnetoelectric composites as the antenna vibrator by assembling the alloy and macro piezoelectric fiber composites(MFC).Enhancements of magnetic emission intensity are found at 93.3%and 49.2%at the first and second harmonic frequencies compared with the unmodified alloy ***,the approach leads to the development of high-performance communication with a novel standard for evaluation.

关键词： multi-phase amorphous alloys magnetic emission intensity enhancing mechanism magnetic domain pinning theory Jiles-Atherton model analysis

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心理咨询师胜任特征的定性研究

中国心理卫生杂志 2010年第10期24卷 731-736页

作者：吴垠桑志芹南京大学社会学院应用心理学系南京210093 南京大学心理健康教育与研究中心南京210093

目的:构建心理咨询师胜任特征模型。方法:对20名心理咨询师进行行为事件访谈,以"国家首批注册心理督导师"为效标,将访谈对象分为绩优组和一般组,每组各10名。编写《心理咨询师胜任特征研究编码手册》,根据编码手册中的23个胜任特征条目... 详细信息

目的:构建心理咨询师胜任特征模型。方法:对20名心理咨询师进行行为事件访谈,以"国家首批注册心理督导师"为效标,将访谈对象分为绩优组和一般组,每组各10名。编写《心理咨询师胜任特征研究编码手册》,根据编码手册中的23个胜任特征条目及其等级评分标准,对访谈资料进行编码分析。使用Mann-Whitney U检验,考察在绩优组和一般组之间存在差异的条目,初步得到心理咨询师鉴别性胜任特征;考察出现频次较高的条目,初步得到心理咨询师基准性胜任特征。采用"内容评价小组"方法,通过计算各条目的内容效度比率(content validity ratio,CVR),对初步得到的胜任特征进行内容效度检验。结果:两组心理咨询师在建立关系的基本态度、人际理解和洞察、弹性、影响力、自我觉察、自我控制力、人格健全与完善、阅历与经验、专业知识与技能9个条目上差异有统计学意义(P0.33),将其定义为"鉴别性胜任特征"。编码结果中出现频次较高,且通过内容效度检验(CVR>0.33)的11个条目为利他性、建立关系的基本态度、人际理解和洞察、尊重、培养他人、自我觉察、自我控制力、开放性、语言表达能力、人格健全与完善、专业知识和技能,定义为"基准性胜任特征"。结论:心理咨询师胜任特征模型包括"基准性胜任特征"和"鉴别性胜任特征"两个部分。

关键词：心理咨询师胜任特征模型鉴别性胜任特征基准性胜任特征行为事件访谈

Measurement of the high energyγ-rays from heavy ion reactions usingČerenkov detector

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Nuclear Science and Techniques 2024年第2期35卷 123-130页

作者： Da-Wei Si Yan Zhou Sheng Xiao zhi qin Dong Guo Yu-Hao qin Yi-Jie Wang Bo-Yuan Zhang Bai-Ting Tian zhi-Gang Xiao Department of Physics Tsinghua UniversityBeijing 100084China

The energetic bremsstrahlung photons up to 100 MeV produced in heavy ion collisions can be used as a sensitive probe for short-range correlation in atomic nuclei. The energy of the γ-rays can be measured by collecting the Čerenkov light in the medium induced by the fast electrons generated in the Compton scattering or electromagnetic shower of the incident γray. Two types of detectors based on pure water and lead glass as sensitive materials were designed for this purpose. The γresponse and optical photon propagation in the detectors were simulated based on electromagnetic and optical processes in Geant4. The inherent energy resolutions of 0.022(4) + 0.51(2)∕E^(1/2)_(γ) for water and 0.0026(3) + 0.446(3)∕E^(1/2)_(γ) for lead glass were obtained. The geometry sizes of the lead glass and water were optimized to 30 cm × 30 cm × 30 cm and 60 cm × 60 cm ×120 cm, respectively, to detect high-energy γ-rays at 160 MeV. The Hough transform method was applied to reconstruct the direction of the incident γ-rays, providing the ability to experimentally distinguish the high-energy γ-rays produced in the reactions on the target from random background cosmic-ray muons.

关键词： Bremsstrahlungγ-rays Čerenkov Geant4 Energy resolution Direction reconstruction Hough transform

Sparse antenna array design methodologies:A review

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Journal of Electronic Science and Technology 2024年第3期22卷 1-15页

作者： Pan Wu Yan-Hui Liu zhi-qin Zhao qing-Huo Liu School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China Eastern Institute of Technology Ningbo315200China

Designing a sparse array with reduced transmit/receive modules(TRMs)is vital for some applications where the antenna system’s size,weight,allowed operating space,and cost are *** arrays exhibit distinct architectures,roughly classified into three categories:Thinned arrays,nonuniformly spaced arrays,and clustered *** numerous advanced synthesis methods have been presented for the three types of sparse arrays in recent years,a comprehensive review of the latest development in sparse array synthesis is *** work aims to fill this gap by thoroughly summarizing these *** study includes synthesis examples to facilitate a comparative analysis of different techniques in terms of both accuracy and ***,this review is intended to assist researchers and engineers in related fields,offering a clear understanding of the development and distinctions among sparse array synthesis techniques.

关键词： Clustered array Nonuniformly spaced array Sparse antenna array Synthesis method Thinned array

Microphase Separation of Semiflexible Ring Diblock Copolymers

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Chinese Journal of Polymer Science 2024年第2期42卷 267-276,I0011页

作者： Dan-Yan qin Sheng-Da Zhao zhi-Xin Liu Jing Zhang Xing-Hua Zhang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing100044China

Aiming at the difficult problem of solving the conformation statistics of complex polymers, this study presents a novel and concise conformation statistics theoretical approach based on Monte Carlo and Neural Network method. This method offers a new research idea for investigating the conformation statistics of complex polymers, characterized by its simplicity and practicality. It can be applied to more complex topological structure, more higher degree of freedom polymer systems with higher dimensions, theory research on dynamic self-consistent field theory and polymer field theory, as well as the analysis of scattering experimental data. The conformation statistics of complex polymers determine the structure and response properties of the system. Using the new method proposed in this study, taking the semiflexible ring diblock copolymer as an example, Monte Carlo simulation is used to sample this ring conformation to construct the dataset of polymer. The structure factor describing conformation statistics are expressed as continuous functions of structure parameters by neural network supervised learning. This is the innovation of this work. As an application, the structure factors represented by neural networks were introduced into the random phase approximation theory to study the microphase separation of semiflexible ring diblock copolymers. The influence of the ring's topological properties on the phase transition behavior was pointed out.

关键词： Ring copolymer Diblock copolymers Semiflexible The order-disorder transition

Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang Xie zhi-Liang qin Jian-Hua Wang Peng Song Heng-Guang Shen Sheng-Qi Yu Ben-Jun Ma Xue-qin Liu qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute Co. Ltd.Beijing100028China College of Marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment Co. Ltd.Weihai264209ShandongChina

The low-wavenumber components in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber components in the gradient will also reduce the convergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient combines the conventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber components in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber components in the high-frequency inversion to improve the convergence *** results of synthetic data experiment demonstrate that compared to the conventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber components in the gradient under the premise of ensuring inversion *** also greatly enhances the convergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber component