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Breeding and Seed Reproduction Techniques of a New Tetraploid Common Buckwheat Variety‘Pintianqiao 3’
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作者 Xinghai SHI Jiandong ZHAO +5 位作者 Xiulian LI Wenliang CHEN Xiuzhen QIN Jun REN Xiaohuan YANG Jinhu MA 《Agricultural Biotechnology》 2024年第3期5-7,13,共4页
[Objectives]This study was conducted to actively carry out the breeding of new tetraploid common buckwheat varieties and its supporting breeding techniques.[Methods]Pintianqiao 3 is a new tetraploid common buckwheat v... [Objectives]This study was conducted to actively carry out the breeding of new tetraploid common buckwheat varieties and its supporting breeding techniques.[Methods]Pintianqiao 3 is a new tetraploid common buckwheat variety developed by College of Agriculture of Shanxi Agricultural University and Agricultural Genetic Resources Center of Shanxi Agricultural University,using‘Pintianqiao 1’as the parent,through mutation treatment with 0.2%colchicine aqueous solution,grain selection,plant selection,isolation and identification,variety comparison,regional test and field investigation.The variety has chromosomes 2n=4X=32,and shows a spring sowing period of 101 d and a summer sowing period of 80 d,large flowers and seeds(with a 1000-grain weight of 41.4 g),and good resistance to lodging.[Results]From 2021 to 2022,Pintianqiao 3 participated in the independent joint regional test of common buckwheat varieties in Shanxi Province,and the average yield in 10 test positions was 1.8 kg,equivalent to 1800 kg/hm^(2),which was 8.4%higher than the control.It passed the field investigation conducted by Shanxi provincial expert group for identification of non-major crop varieties in Dongyang and Kelan experimental sites on September 2-3,2022.On January 4,2024,it passed the preliminary examination of Shanxi Provincial Crop Variety Approval Committee.The seed reproduction technique of Pintianqiao 3 including land selection,preparation before sowing,sowing,field management and timely harvesting has been developed.[Conclusions]This study provides technical support for the demonstration and popularization of this new variety. 展开更多
关键词 TETRAPLOID Pintianqiao 3 BREEDING CHARACTERIsTIC Breeding technique
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以护士为主导构建1M3S模式的闭环管理体系在儿童血标本管理中的应用价值
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作者 伍敏仪 杨美霞 +5 位作者 蔡楚云 李妙玲 李智雅 麦秀连 李桂花 陈雄毅 《基层医学论坛》 2025年第2期122-124,132,共4页
目的探讨以护士为主导构建1M3S模式的闭环管理体系在儿童医学中心血标本管理中的应用效果。方法2023年12月—2024年2月肇庆市第一人民医院开展基于护士为主导构建儿童医学中心血标本1M3S模式的闭环管理体系。由普儿科、儿童重症监护室(p... 目的探讨以护士为主导构建1M3S模式的闭环管理体系在儿童医学中心血标本管理中的应用效果。方法2023年12月—2024年2月肇庆市第一人民医院开展基于护士为主导构建儿童医学中心血标本1M3S模式的闭环管理体系。由普儿科、儿童重症监护室(pediatric intensive care unit,PICU)、新生儿科、检验科、临床支持中心等多方联动开展一系列活动,组员集体发挥主观能动性,分析儿童医学中心血标本管理存在的问题,根据现状结合1M3S管理模式提出改进策略。比较1M3S模式实施前后的儿童血标本不合格率、血标本运送时间、护士规范化培训率、送检人员规范化培训率。结果实施1M3S模式后,新生儿科血标本不合格率由2.70%降至1.50%,普儿科血标本不合格率由1.25%降至0.60%,PICU血标本不合格率由1.48%降至0.79%。实施1M3S模式后,血标本运送时间由平均30 min降至平均18 min,护士培训率由50.00%增至100.00%,送检人员培训率由40.00%增至100.00%。结论基于护士为主导构建儿童医学中心血标本1M3S模式的闭环管理体系,能降低儿童血标本不合格率,提高送检效率。 展开更多
关键词 1M3s模式 闭环管理 儿童医学中心 血标本
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Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats
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作者 Pengfei Wang Yuewei Bi +6 位作者 Min Li Jiazhi Chen Zhuyong Wang Huantao Wen Ming Zhou Minjie Luo Wangming Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1164-1177,共14页
Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Cu... Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Currently,studies have reported increased oscillation power in cases of levodopa-induced dyskinesia.However,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced dyskinesia.Furthermore,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is unclear.We found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s disease.Furthermore,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma flow.Administration of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum flow.However,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum direction.These findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia. 展开更多
关键词 aperiodic components dopamine D3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials NEUROMODULATION Parkinson’s disease primary motor cortex
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地质矿产勘查中3S技术的应用
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作者 韩京华 《中文科技期刊数据库(引文版)工程技术》 2025年第1期124-127,共4页
地质矿产的勘探被视为资源利用的关键步骤,而3S技术(GIS、RS、GPS)的使用为这一领域开辟了诸多新的可能性和面临的试炼。本研究深入探索了3S技术在地质矿产勘探活动中的实际运用,涵盖了GIS技术在数据维护和整体评价上的重要性、RS技术... 地质矿产的勘探被视为资源利用的关键步骤,而3S技术(GIS、RS、GPS)的使用为这一领域开辟了诸多新的可能性和面临的试炼。本研究深入探索了3S技术在地质矿产勘探活动中的实际运用,涵盖了GIS技术在数据维护和整体评价上的重要性、RS技术在地质特征的监测以及矿石的探索中的作用,还有GPS在准确定位和即时监控上的关键作用。通过将这三项关键技术有机融合与应用,调查工作不仅提高了工作效率和精确度,而且也促进了资源的科学管理和可持续使用。除此之外,这篇文章还详细探讨了各种技术在实际操作中所遭遇的难题,并突出了在将来的勘探过程中对技术持续创新和完善的必要性。 展开更多
关键词 地质矿产 勘查 3s技术 应用
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3S集成技术在征地和房屋拆迁测绘中的应用
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作者 梁家龙 《中文科技期刊数据库(全文版)自然科学》 2025年第1期025-028,共4页
传统征地拆迁工作模式存在征拆测量工作分离的现象,不仅会消耗大量的人力与物力,而且工作效率低,同时还存在无法建立征地拆迁成果数据库以及数据难以管理等问题。3S集成技术是多种现代测绘测量技术的结合,实现了技术之间的优势互补,3S... 传统征地拆迁工作模式存在征拆测量工作分离的现象,不仅会消耗大量的人力与物力,而且工作效率低,同时还存在无法建立征地拆迁成果数据库以及数据难以管理等问题。3S集成技术是多种现代测绘测量技术的结合,实现了技术之间的优势互补,3S集成技术的应用,有助于提升测绘精度,同时也能实现对测绘数据的高效管理,使外业测绘不再受时空的桎梏,可以为拆迁工作节约大量的时间与人力投入。基于此,本文介绍3S及其集成技术,并就3S集成技术在征地和房屋拆迁测绘中的应用进行探究。 展开更多
关键词 3s集成技术 征地和房屋拆迁 房产测绘 遥感技术
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3S一体化技术在口袋公园规划建设中的应用探讨——以清灵毓秀口袋公园为例
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作者 孙允聪 张婷婷 《科学技术创新》 2025年第4期151-154,共4页
在我国城市发展过程中,充分利用边角余料地块建设小巧美观的口袋公园对提升城市品质,改善人民生活具有重要作用。结合口袋公园建设基本特点,介绍了3S一体化技术与VR技术在口袋公园规划建设中的思路与应用,为口袋公园规划建设提供参考。
关键词 口袋公园 3s一体化技术 GIs技术体系 方案编制与优化
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“3S”理念视域下的高中数学建模课程建设
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作者 黄信 赵芃 《教育科学论坛》 2025年第5期53-55,共3页
“3S”科学教育理念的核心是学校在构建课程体系时融入科普启蒙(science-oriented thinking)、科学教育(science-oriented education)、科创实践(science-oriented innovation)的育人价值追求。基于“3S”科学教育理念,建设高中数学建... “3S”科学教育理念的核心是学校在构建课程体系时融入科普启蒙(science-oriented thinking)、科学教育(science-oriented education)、科创实践(science-oriented innovation)的育人价值追求。基于“3S”科学教育理念,建设高中数学建模的三维课程体系,即数学建模选修课程的“科普启蒙”体系、数学建模活动课程的“科创实践”体系、数学建模集训课程的“科学教育”体系,为高中数学建模课程建设提供了新的路径。 展开更多
关键词 高中数学建模 科学教育 课程建设 “3s”理念
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基于ESP32的仿生四足机械狮子十二自由度结构设计
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作者 郭长昊 袁成凯 +3 位作者 张凤羽 李明远 陆庆智 穆德敏 《南方农机》 2025年第1期161-163,共3页
仿生机器人是近年来研究的热门课题,机器人的应用场景越来越多,应用价值也越来越大。但市场上大多数仿生四足机器人灵活度较低。基于此,设计并实现了基于ESP32的十二自由度的仿生四足机械狮子。该机械狮子软件设计采用了Arduino作为PC... 仿生机器人是近年来研究的热门课题,机器人的应用场景越来越多,应用价值也越来越大。但市场上大多数仿生四足机器人灵活度较低。基于此,设计并实现了基于ESP32的十二自由度的仿生四足机械狮子。该机械狮子软件设计采用了Arduino作为PC端的开发平台,同时支持MicroPython和Mixly程序开发,通过3D打印技术制作身体框架,利用多个舵机相连实现十二自由度设计;该机械狮子以ESP32模块为主控模块,与ESP32CAM、SU-03T等模块相结合,实现了模仿狮子的行走、坐下、起卧、跳舞等动作。仿真结果表明,该机械狮子具有灵活简便的结构设计,具有智能化语音、视觉控制、功耗低、负载大等优势,解决了四足机器人灵活度低、成本高等问题。 展开更多
关键词 EsP32 仿生四足机械狮子 十二自由度 MG90s舵机 3D打印
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The Application of Analytical Techniques to Alpha-Synuclein in Parkinson’s Disease
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作者 Olatayo Adedayo Olahanmi 《American Journal of Analytical Chemistry》 CAS 2024年第9期269-285,共17页
Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by motor symptoms such as tremors, rigidity, and bradykinesia, as well as non-motor symptoms including cognitive impairment and mood ... Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by motor symptoms such as tremors, rigidity, and bradykinesia, as well as non-motor symptoms including cognitive impairment and mood disorders. A hallmark of PD is the accumulation of alpha-synuclein, a presynaptic neuronal protein that aggregates to form Lewy bodies, leading to neuronal dysfunction and cell death. The study of alpha-synuclein and its pathological forms is crucial for understanding the etiology of PD and developing effective diagnostic and therapeutic strategies. Analytical techniques play a pivotal role in elucidating the structure, function, and aggregation mechanisms of alpha-synuclein. Biochemical methods such as Western blotting and enzyme-linked immunosorbent assay (ELISA) are employed to detect and quantify alpha-synuclein in biological samples, offering insights into its expression levels and post-translational modifications. Imaging techniques like immunohistochemistry and positron emission tomography (PET) allow for the visualization of alpha-synuclein aggregates in tissue samples and in vivo, respectively, facilitating the study of its spatial distribution and progression in PD Spectroscopic methods, including nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry, provide detailed structural information on alpha-synuclein and its isoforms, aiding in the identification of conformational changes associated with aggregation. Emerging techniques such as cryo-electron microscopy (Cryo-EM) and single-molecule fluorescence enable high-resolution structural analysis and real-time monitoring of alpha-synuclein aggregation dynamics, respectively. The application of these analytical techniques has significantly advanced our understanding of the pathophysiological role of alpha-synuclein in PD. They have contributed to the identification of potential biomarkers for early diagnosis and the evaluation of therapeutic interventions targeting alpha-synuclein aggregation. Despite technical limitations and challenges in clinical translation, ongoing advancements in analytical methodologies hold promise for improving the diagnosis, monitoring, and treatment of Parkinson’s disease through a deeper understanding of alpha-synuclein pathology. 展开更多
关键词 Parkinson’s Disease ALPHA-sYNUCLEIN techniques
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The Application and Operation-Effect Analysis for Complex Tibial Plateau Fractures with 3D Printing Technique 被引量:3
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作者 Changjin Guo Yubo Zhang +2 位作者 Li Yang Qiaofeng Zhu Sanming Zou 《International Journal of Clinical Medicine》 2019年第3期101-108,共8页
Objective: To investigate the value of 3D printing techniques in the treatment of complex tibial plateau fractures. Methods: From September 2016 to September 2018, 28 patients with complex tibial plateau fractures wer... Objective: To investigate the value of 3D printing techniques in the treatment of complex tibial plateau fractures. Methods: From September 2016 to September 2018, 28 patients with complex tibial plateau fractures were treated in our hospital. According to the odevity of hospitalized order, the patients were divided into two groups. Group A used 3D reconstruction, virtually reduction, 3D printing and demonstration of individual fracture model before operation while group B only received conventional process by use X-rays or CT image. Comparison between the two groups was made in operation time, operative blood loss, radiation frequency, surgery instrument cost and knee function score. Results: The follow-up was 14.4 months on average (ranged 6 to 22 months). There was no statistical difference of the surgery instrument cost between the 2 groups (P > 0.05). The operation time of group A was significantly shorter than that of group B (P χ2 = 0.373, P = 0.54). Conclusion: 3D printing techniques can improve surgery effect in complex tibial plateau fractures. 展开更多
关键词 TIBIAL PLATEAU FRACTURE 3D PRINTING technique Individualized Treatment
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Assessment of the effects of induced anisometropia on binocularity with glasses-free 3D technique 被引量:1
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作者 Xu-Bo Yang Wei-Dong Huang Yong-Chuan Liao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第4期601-607,共7页
AIM:To assess the effect of experimentally induced anisometropia on binocularity in normal adults with glassesfree three-dimensional(3D)technique.METHODS:Totally 54 healthy medical students with normal binocularity in... AIM:To assess the effect of experimentally induced anisometropia on binocularity in normal adults with glassesfree three-dimensional(3D)technique.METHODS:Totally 54 healthy medical students with normal binocularity in the cross-sectional study were enrolled.Anisometropia was induced by placing trail lenses over the right eye,in 0.5 D steps including lenses of-0.5,-1,-1.5,-2,-2.5 D(hyperopic anisometropia)and lenses of+0.5,+1,+1.5,+2,+2.5 D(myopic anisometropia).The glasses-free 3D technique was used to evaluated not only fine stereopsis,but also coarse stereopsis,dynamic stereopsis,foveal suppression,and peripheral suppression in these subjects.One-way analysis of variance was used to compare quantitative data such as fine stereopsis,coarse stereopsis.Pearson’s Chi-square test was performed to compare categorical data such as dynamic stereopsis,foveal suppression and peripheral suppression.RESULTS:The subjects showed a statistically significant decline in fine stereopsis,coarse stereopsis,and dynamic stereopsis with increasing levels of anisometropia(P<0.001).Binocularity was af fected when induced anisometropia was more than 1 D(P<0.05).Foveal suppression and peripheral suppression were evident and increased in proportion to anisometropia(P<0.001).CONCLUSION:The relatively low degrees of anisometropia may have a potentially significant effect on high-grade binocular interaction.The mechanisms underlying the defect of binocularity seem to involve not only foveal suppression,but also peripheral suppression. 展开更多
关键词 ANIsOMETROPIA binocularity sTEREOPsIs glasses-free 3D technique
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Kinetics and the difference for extraction of praseodymium and neodymium from nitrate aqueous solution by [A336][NO_3] using the single drop technique 被引量:1
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作者 Xiaoqin Wang Kun Huang +3 位作者 Wenjuan Cao Pan Sun Weiyuan Song Huizhou Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第5期1326-1333,共8页
The kinetics and the difference for Pr(Ⅲ)and Nd(Ⅲ)extraction from nitrate aqueous solution using trialkylmethylammonium nitrate([A336][NO3])as extractant were investigated by the single drop technique.The dependence... The kinetics and the difference for Pr(Ⅲ)and Nd(Ⅲ)extraction from nitrate aqueous solution using trialkylmethylammonium nitrate([A336][NO3])as extractant were investigated by the single drop technique.The dependence of the extraction rate of Pr(Ⅲ)and Nd(Ⅲ)on the concentrations of free Pr(Ⅲ)and Nd(Ⅲ)ions,the concentrations of Na NO3 and H+in aqueous solutions,and the concentrations of[A336][NO3]in kerosene solutions were discussed and the corresponding extraction rate equations for Pr(Ⅲ)and Nd(Ⅲ)were obtained.These equations demonstrated that the reaction rate constant of Pr(Ⅲ)with[A336][NO3]was double than that of Nd(Ⅲ).The effect of the addition of diethylenetriaminepentaacetic acid(DTPA)on the difference in the extraction rate of Pr(Ⅲ)and Nd(Ⅲ)by[A336][NO3]was also investigated.It was revealed that the difference in the complex formation rates of Pr(Ⅲ)and Nd(Ⅲ)with DTPA made a significant impact on the difference in the extraction rates of Pr(Ⅲ)and Nd(Ⅲ)with[A336][NO3].The ratio of extraction rates of Pr(Ⅲ)to Nd(Ⅲ)with[A336][NO3]was in proportion to the ratio of complex formation rates of Pr(Ⅲ)to Nd(Ⅲ)with DTPA.The extraction rate difference for Pr(Ⅲ)and Nd(Ⅲ)with[A336][NO3]increased due to a higher complex formation rate constant of DTPA with the free and un-complexed Nd(Ⅲ)ions in the aqueous nitrate solution than that with Pr(Ⅲ)ions.Therefore,the addition of DTPA in the aqueous nitrate solution is an effective method to intensify the separation of Pr(Ⅲ)and Nd(Ⅲ)in kinetics.The study on the extraction mechanism indicated that both the extraction of Pr(Ⅲ)and Nd(Ⅲ)by[A336][NO3]were diffusion controlled,and the reactions obeyed SN2 mechanism.The present work highlights a possible approach to strengthen the kinetic separation of Pr(Ⅲ)and Nd(Ⅲ). 展开更多
关键词 PRAsEODYMIUM NEODYMIUM [A336][NO3] KINETICs single drop technique
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Permittivity of composites used for Luneburg lens antennas by drilling holes based on 3-D printing technique
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作者 DONG Changsheng CUI Ziqing +3 位作者 LI Yong WANG Haidong JIN Chao YANG Shiwen 《太赫兹科学与电子信息学报》 2017年第4期646-651,共6页
Due to the attractive performances such as the ability of beam focus,broadband,multi-beam scanning and other features,Luneburg lens antennas are applied in multi-beam antenna,which overcomes the problem of gain loss p... Due to the attractive performances such as the ability of beam focus,broadband,multi-beam scanning and other features,Luneburg lens antennas are applied in multi-beam antenna,which overcomes the problem of gain loss produced by multi-beam parabolic antenna.Based on 3-D printing technique,Luneburg lens antennas by drilling holes are studied.Permittivity and loss tangent of the equivalent lens materials can be influenced by original materials,hole shapes,hole directions,and porosity.After tests,polystyrene with waxes may be the most appropriate materials for Luneburg lens with high strength.Permittivity with the shape of triangle is the lowest due to the homogeneity.Relative permittivities with the direction at a range of 15°-45°are lower while loss tangent at a range of 0°-30°.Radial directional holes are more appropriate for Luneburg lens.The relative permittivity is decreased with the increment of porosity.After calculations,the forecasts calculated by Looyenga and A-BG theory are more precise.Finally,Luneburg lens with two layers is fabricated by 3-D printing. 展开更多
关键词 Luneburg lens by DRILLING HOLEs 3-D PRINTING technique PERMITTIVITY
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FABRICATION OF HIGHLY HYDROPHOBIC FILMS OF POLY(3-HEXADECYL PYRROLE) NANOPARTICLES BY LANGMUIR-BLODGETT TECHNIQUE
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作者 石高全 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第5期457-462,共6页
Thin films of poly(3-hexadecyl pyrrole) (P3HDP) nanoparticles have been fabricated by using Langmuir-Blodgett film deposition technique. The structures and morphology of the films were studied by using infrared sp... Thin films of poly(3-hexadecyl pyrrole) (P3HDP) nanoparticles have been fabricated by using Langmuir-Blodgett film deposition technique. The structures and morphology of the films were studied by using infrared spectroscopy, scanning and transmission microscopes. The experimental results demonstrated that the nanoparticles were formed by self-assembling P3HDP at air-water surface. The water contact angles of these films with different deposition layers were measured to be as high as 110°. 展开更多
关键词 Poly(3-hexadecyl pyrrole) LB technique High hydrophobicity.
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Variety Characteristics and Cultivation Techniques of Rape Changzayou 3
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作者 胡金荣 朱传霞 +3 位作者 薛高尚 杨鸿 罗晓玲 柏秀芳 《Agricultural Science & Technology》 CAS 2016年第9期2046-2047,共2页
High-quality hybrid rape Changzayou 3 is a new yellow-seed double-low rape variety with high yield, good resistance to diseases and lodging and high oil content, suitable for winter cropping in central China. Its high... High-quality hybrid rape Changzayou 3 is a new yellow-seed double-low rape variety with high yield, good resistance to diseases and lodging and high oil content, suitable for winter cropping in central China. Its high-yield cultivation tech- niques are mainly early seeding at proper time, thinning timely, rational close planting, scientific fertilization, control of diseases and pest and weeding. 展开更多
关键词 RAPE Variety characteristics Cultivation technique Changzayou 3
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32×32 Si盖革模式激光焦平面探测器 被引量:1
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作者 王江 王鸥 +5 位作者 刘向东 袁利 柯尊贵 郝昕 覃文治 杨赟秀 《激光技术》 CAS CSCD 北大核心 2024年第5期665-670,共6页
为了满足350 nm~1100 nm波长范围内远距离及微弱激光3维成像探测的需求,提出了一种规模为32×32的盖革模式硅激光焦平面阵列探测器,它主要由硅雪崩光电二极管阵列、读出电路芯片、微透镜阵列、半导体制冷器、引脚网格阵列壳体等元... 为了满足350 nm~1100 nm波长范围内远距离及微弱激光3维成像探测的需求,提出了一种规模为32×32的盖革模式硅激光焦平面阵列探测器,它主要由硅雪崩光电二极管阵列、读出电路芯片、微透镜阵列、半导体制冷器、引脚网格阵列壳体等元件组成。硅雪崩光电二极管焦平面阵列采用拉通型N^(+)-Π_(1)-P^(-)-Π_(2)-P^(+)结构,工作在盖革模式下,通过Si片背面抛磨减薄及盲孔刻蚀技术,实现了纤薄光敏区的加工;读出电路采用主动模式淬灭设计,使电路单元的死时间控制在50 ns以内,并利用一种带相移技术的时间数字转换电路优化方案,在满足时间分辨率不大于2 ns的同时,降低了读出电路芯片的功耗。结果表明,在反向过偏电压14 V、工作温度-40℃的条件下,该探测器在850 nm的目标波长可实现20.7%的平均光子探测效率与0.59 kHz的平均暗计数率,时间分辨率为1 ns,有效像元率优于97%。该研究为纤薄型背进光Si基激光焦平面探测器的研制提供了参考。 展开更多
关键词 传感器技术 雪崩焦平面探测器 盖革模式 激光3维成像
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Study on the 3D Seismic Data Field Hybrid Rendering Technique of Natural Gas Hydrate and Its Application
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作者 Pan LI Zhaojun ZHOU Meng HUANG 《International Journal of Technology Management》 2013年第2期50-52,共3页
3D visualization technology is a tool used for displaying, describing, and understanding the characteristics of geologic bodies, and features high efficiency, objective accuracy, visual expression, etc. In this paper,... 3D visualization technology is a tool used for displaying, describing, and understanding the characteristics of geologic bodies, and features high efficiency, objective accuracy, visual expression, etc. In this paper, the man-machine interactive interpretation and 3D visualization technology rapidly displaying and analyzing the 3D seismic data of hydrate ore volume is researched and developed using the hybrid rendering technique. Through the integrated interpretation on the 3D space structure, stratum, and seismic attributes, the visualized multi-attribute superimposition analysis is implemented for describing the spatial distribution characteristics of hydrate ore volume and exquisitely describing the subtle geological characteristics of hydrate ore volume. By the hybrid rendering technique, authentication and interpretation are provided for the geological exploration work, so as to greatly enhance the visualization and accuracy of the geological analysis, and also provide a good decision-making foundation for the subsequent development of resources. 展开更多
关键词 Natural Gas Hydrate 3D seismic Data Hybrid Rendering technique
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S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3)的构筑及光催化还原CO_(2)性能 被引量:1
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作者 刘平 朱成才 +1 位作者 李艳阳 要红昌 《无机化学学报》 SCIE CSCD 北大核心 2024年第1期197-208,共12页
通过在WO_(3)纳米片表面负载ZnFe_(2)O_(4)纳米颗粒,构建了一系列S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3),并研究了其光催化CO_(2)还原性能。在没有助催化剂和牺牲剂的条件下,所制备的ZnFe_(2)O_(4)/WO_(3)复合材料可对CO_(2)与水蒸汽... 通过在WO_(3)纳米片表面负载ZnFe_(2)O_(4)纳米颗粒,构建了一系列S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3),并研究了其光催化CO_(2)还原性能。在没有助催化剂和牺牲剂的条件下,所制备的ZnFe_(2)O_(4)/WO_(3)复合材料可对CO_(2)与水蒸汽进行光催化反应。优化后的材料光照5 h后CO_(2)还原产物CO和CH_(4)的产量分别为7.87和4.88μmol·g^(-1)。相对于单相组分,CO和CH_(4)的产量明显提高。光催化活性的提高,归因于ZnFe_(2)O_(4)和WO_(3)异质结的形成以及光生载流子的S型电荷传输模式。 展开更多
关键词 CO_(2)还原 光催化活性 ZnFe_(2)O_(4)/WO_(3) 异质结 s型电荷传输模式
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S3级临床实践指南在口腔医学的发展应用 被引量:1
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作者 陈智 黄心悦 《口腔医学研究》 CAS CSCD 北大核心 2024年第1期1-5,共5页
在口腔医学领域,新的国际S3级指南的出现为相关疾病患者的管理提供了高质量的推荐建议,在国际性指南的基础上,也需结合我国的实际情况进行改编和应用。本文旨在介绍S3级临床实践指南分级系统和基本方法学原理,并对指南改编和本土化应用... 在口腔医学领域,新的国际S3级指南的出现为相关疾病患者的管理提供了高质量的推荐建议,在国际性指南的基础上,也需结合我国的实际情况进行改编和应用。本文旨在介绍S3级临床实践指南分级系统和基本方法学原理,并对指南改编和本土化应用现状进行简要介绍。 展开更多
关键词 临床实践指南 s3级指南 ADOLOPMENT 临床实践
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改进YOLOv5s的小样本3D打印点阵结构表面缺陷检测 被引量:1
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作者 安治国 鲜青霖 许亮 《重庆理工大学学报(自然科学)》 CAS 北大核心 2024年第8期173-180,共8页
3D打印点阵结构已经广泛应用于航空航天、机械和建筑等行业,其表面缺陷分布不均匀且特征微弱,常常造成漏检和误检。针对这一问题,提出了一种YOLOv5s-PD模型。在该模型中,添加了XSPPF模块和空洞金字塔池化模块,提高了模型对不同缺陷特征... 3D打印点阵结构已经广泛应用于航空航天、机械和建筑等行业,其表面缺陷分布不均匀且特征微弱,常常造成漏检和误检。针对这一问题,提出了一种YOLOv5s-PD模型。在该模型中,添加了XSPPF模块和空洞金字塔池化模块,提高了模型对不同缺陷特征的获取能力;针对3D打印点阵结构表面缺陷分布杂乱导致误检率高的问题,在YOLOv5s模型中加入了ECA模块;考虑到3D打印点阵结构表面缺陷尺寸信息无规律并且差异较大而导致的预测框与真实框间方向不一致,采用了SIoU损失函数。采用改进模型对制作的3D打印点阵结构表面缺陷数据集进行检测,结果表明:缺陷检测的召回率达到94.0%,平均精度mAP@0.5达到96.2%,所提出的改进算法可以实现对3D打印点阵结构表面缺陷自动检测。 展开更多
关键词 3D打印 点阵结构 YOLOv5s 缺陷检测 平均精度
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