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Fabrication of UV-Curing Linalool-Polysiloxane Hybrid Films with High Refractive Index and Transparency
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作者 Wenqing Xiao Lewen Tan +2 位作者 Xunjun Chen Qiaoguang Li Yunqing Ruan 《Journal of Renewable Materials》 EI CAS 2024年第3期569-583,共15页
In this article,a series of high refractive indices(1.50-1.53)thiol phenyl polysiloxane(TPS)were synthesized via hydrolytic sol-gel reaction.The Fourier transform infrared spectra(FT-IR)and nuclear magnetic resonance ... In this article,a series of high refractive indices(1.50-1.53)thiol phenyl polysiloxane(TPS)were synthesized via hydrolytic sol-gel reaction.The Fourier transform infrared spectra(FT-IR)and nuclear magnetic resonance spectra(NMR)results showed that TPS conformed to the predicted structures.Natural terpene linalool was exploited as photocrosslinker to fabricate UV-curing linalool-polysiloxane hybrid films(LPH)with TPS via photoinitiated thiol-ene reaction.LPH rapidly cured under UV irradiation at the intensity of 80 mW/cm^(2) in 30 s,exhibiting good UV-curing properties.The optical transmittance of LPH in the wavelength of 300-800 nm was over 90%,exhibiting good optical transparency.The water contact angle and water vapor permeability results showed that the introduction of phenyl groups enhance the hydrophobicity and water vapor barrier properties of LPH.The results indicated the potential of LPHs in the applications of optical functional coatings. 展开更多
关键词 UV-CURING polysiloxane hybrid films high refractive index TRANSPARENCY
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Double-Layer-Optimizing Method of Hybrid Energy Storage Microgrid Based on Improved Grey Wolf Optimization
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作者 Xianjing Zhong Xianbo Sun Yuhan Wu 《Computers, Materials & Continua》 SCIE EI 2023年第8期1599-1619,共21页
To reduce the comprehensive costs of the construction and operation of microgrids and to minimize the power fluctuations caused by randomness and intermittency in distributed generation,a double-layer optimizing confi... To reduce the comprehensive costs of the construction and operation of microgrids and to minimize the power fluctuations caused by randomness and intermittency in distributed generation,a double-layer optimizing configuration method of hybrid energy storage microgrid based on improved grey wolf optimization(IGWO)is proposed.Firstly,building a microgrid system containing a wind-solar power station and electric-hydrogen coupling hybrid energy storage system.Secondly,the minimum comprehensive cost of the construction and operation of the microgrid is taken as the outer objective function,and the minimum peak-to-valley of the microgrid’s daily output is taken as the inner objective function.By iterating through the outer and inner layers,the system improves operational stability while achieving economic configuration.Then,using the energy-self-smoothness of the microgrid as the evaluation index,a double-layer optimizing configuration method of the microgrid is constructed.Finally,to improve the disadvantages of grey wolf optimization(GWO),such as slow convergence in the later period and easy falling into local optima,by introducing the convergence factor nonlinear adjustment strategy and Cauchy mutation operator,an IGWO with excellent global performance is proposed.After testing with the typical test functions,the superiority of IGWO is verified.Next,using IGWO to solve the double-layer model.The case analysis shows that compared to GWO and particle swarm optimization(PSO),the IGWO reduced the comprehensive cost by 15.6%and 18.8%,respectively.Therefore,the proposed double-layer optimizationmethod of capacity configuration ofmicrogrid with wind-solar-hybrid energy storage based on IGWO could effectively improve the independence and stability of the microgrid and significantly reduce the comprehensive cost. 展开更多
关键词 Wind-solar microgrid hybrid energy storage optimization configuration double-layer optimization model IGWO
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Machine Learning for Hybrid Line Stability Ranking Index in Polynomial Load Modeling under Contingency Conditions
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作者 P.Venkatesh N.Visali 《Intelligent Automation & Soft Computing》 SCIE 2023年第7期1001-1012,共12页
In the conventional technique,in the evaluation of the severity index,clustering and loading suffer from more iteration leading to more com-putational delay.Hence this research article identifies,a novel progression f... In the conventional technique,in the evaluation of the severity index,clustering and loading suffer from more iteration leading to more com-putational delay.Hence this research article identifies,a novel progression for fast predicting the severity of the line and clustering by incorporating machine learning aspects.The polynomial load modelling or ZIP(constant impedances(Z),Constant Current(I)and Constant active power(P))is developed in the IEEE-14 and Indian 118 bus systems considered for analysis of power system security.The process of finding the severity of the line using a Hybrid Line Stability Ranking Index(HLSRI)is used for assisting the concepts of machine learning with J48 algorithm,infers the superior affected lines by adopting the IEEE standards in concern to be compensated in maintaining the power system stability.The simulation is performed in the WEKA environment and deals with the supervisor learning in order based on severity to ensure the safety of power system.The Unified Power Flow Controller(UPFC),facts devices for the purpose of compensating the losses by maintaining the voltage characteristics.The finite element analysis findings are compared with the existing procedures and numerical equations for authentications. 展开更多
关键词 CONTINGENCY hybrid line stability ranking index(HLSRI) machine learning(ML) unified power flow controller(UPFC) ZIP load modelling
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Very-High Color Rendering Index Hybrid White Organic Light-Emitting Diodes with Double Emitting Nanolayers 被引量:4
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作者 Baiquan Liu Miao Xu +6 位作者 Lei Wang Hong Tao Yueju Su Dongyu Gao Linfeng Lan Jianhua Zou Junbiao Peng 《Nano-Micro Letters》 SCIE EI CAS 2014年第4期335-339,共5页
A very-high color rendering index white organic light-emitting diode(WOLED) based on a simple structure was successfully fabricated. The optimized device exhibits a maximum total efficiency of 13.1 and 5.4 lm/W at 1,0... A very-high color rendering index white organic light-emitting diode(WOLED) based on a simple structure was successfully fabricated. The optimized device exhibits a maximum total efficiency of 13.1 and 5.4 lm/W at 1,000 cd/m2. A peak color rendering index of 90 and a relatively stable color during a wide range of luminance were obtained. In addition, it was demonstrated that the 4,40,400-tri(9-carbazoyl) triphenylamine host influenced strongly the performance of this WOLED.These results may be beneficial to the design of both material and device architecture for high-performance WOLED. 展开更多
关键词 White light hybrid Color rendering index Organic light-emitting diodes Double emitting nanolayers
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Relationship of Parental Indica-Japonica Indexes with Yield and Grain Quality Traits of Japonica Hybrid Rice in Northern China 被引量:1
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作者 WANG Yan-rong QIu Fu-lin HUA Ze-tian DAI Gui-jin 《Rice science》 SCIE 2010年第3期199-205,共7页
Taking the main parents (10 male sterile lines and 10 restorer lines) and their 100 combinations of japonica hybrid rice in northern China as materials, the relationships of parental indica-japonica indexes determin... Taking the main parents (10 male sterile lines and 10 restorer lines) and their 100 combinations of japonica hybrid rice in northern China as materials, the relationships of parental indica-japonica indexes determined by the methods of the Cheng’s index as well as simple sequence repeat (SSR) markers with yield and grain quality traits of hybrid rice were studied. For the parents, the Cheng’s index (Chi) ranged from 13.5 to 19.3 and the indica index in SSR markers (ADi) were from 0.12 to 0.38. The classification of parents by Chi was not completely consistent with that by ADi. The Chi of male parent was more closely related to hybrid traits than that of female parent, as contrasted to ADi. At the same time, the difference between parents (PD) in Chi was more closely related to hybrid traits than that in ADi. The indica-japonica indexes of parents and their difference between parents appeared quadratic relationship to hybrid traits with the critical extremum. The directions of the correlation of indica-japonica indexes of parents and their differences with hybrid yield traits were on the opposition to those with hybrid grain quality traits. Therefore, the female parent should match the male parent moderately in indica-japonica index to obtain the optimum of hybrid traits, high yield as well as good quality. 展开更多
关键词 japonica hybrid rice indica-japonica index Cheng’s index simple sequence repeat YIELD rice quality
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Comparison of delay compensation methods for real-time hybrid simulation using frequency-domain evaluation index 被引量:1
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作者 Xu Weijie Guo Tong Chen Cheng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2016年第1期129-143,共15页
The delay compensation method plays an essential role in maintaining the stability and achieving accurate real-time hybrid simulation results. The effectiveness of various compensation methods in different test scenar... The delay compensation method plays an essential role in maintaining the stability and achieving accurate real-time hybrid simulation results. The effectiveness of various compensation methods in different test scenarios, however, needs to be quantitatively evaluated. In this study, four compensation methods (i.e., the polynomial extrapolation, the linear acceleration extrapolation, the inverse compensation and the adaptive inverse compensation) are selected and compared experimentally using a frequency evaluation index (FEI) method. The effectiveness of the FEI method is first verified through comparison with the discrete transfer fimction approach for compensation methods assuming constant delay. Incomparable advantage is further demonstrated for the FEI method when applied to adaptive compensation methods, where the discrete transfer function approach is difficult to implement. Both numerical simulation and laboratory tests with predefined displacements are conducted using sinusoidal signals and random signals as inputs. Findings from numerical simulation and experimental results demonstrate that the FEI method is an efficient and effective approach to compare the performance of different compensation methods, especially for those requiring adaptation of compensation parameters. 展开更多
关键词 real-time hybrid simulation frequency domain evaluation index delay compensation methods
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Contrasting Characteristics of Lodging Resistance in Two Super-Rice Hybrids Differing in Harvest Index 被引量:2
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作者 Zui Tao Tao Lei +4 位作者 Fangbo Cao Jiana Chen Xiaohong Yin Tianfeng Liang Min Huang 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第2期429-437,共9页
The“super rice”breeding program in China has been successful in developing high-yielding hybrids,including few with high harvest index values.However,there is limited information on the relationship between lodging ... The“super rice”breeding program in China has been successful in developing high-yielding hybrids,including few with high harvest index values.However,there is limited information on the relationship between lodging resistance and harvest index,and the mechanisms underlying the relationship in super-rice hybrids.In this study,a two-year field experiment was conducted to compare lodging resistance and its related traits between two superrice hybrids differing in harvest index,i.e.,Guiliangyou 2(G2)with a high harvest index and Y-liangyou 1(Y1)with a typical harvest index of modern high-yielding rice varieties.Results showed that compared to Y1,G2 was lower in plant height due to its lower aboveground N uptake,and its higher stem breaking resistance(i.e.,lower stem breaking index)resulted from a lower stem height at its center of gravity.Consequently,G2 had a higher lodging resistance(i.e.,lower plant lodging index)than Y1.This study suggests that developing super-rice hybrids with high harvest index values is a possible way to achieve both high grain yield and strong lodging resistance in rice. 展开更多
关键词 Harvest index nitrogen uptake plant height lodging resistance stem breaking resistance super-rice hybrid
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Forecasting the western Pacific subtropical high index during typhoon activity using a hybrid deep learning model
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作者 Jianyin Zhou Mingyang Sun +3 位作者 Jie Xiang Jiping Guan Huadong Du Lei Zhou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第4期101-108,共8页
Seasonal location and intensity changes in the western Pacific subtropical high(WPSH)are important factors dominating the synoptic weather and the distribution and magnitude of precipitation in the rain belt over East... Seasonal location and intensity changes in the western Pacific subtropical high(WPSH)are important factors dominating the synoptic weather and the distribution and magnitude of precipitation in the rain belt over East Asia.Therefore,this article delves into the forecast of the western Pacific subtropical high index during typhoon activity by adopting a hybrid deep learning model.Firstly,the predictors,which are the inputs of the model,are analysed based on three characteristics:the first is the statistical discipline of the WPSH index anomalies corresponding to the three types of typhoon paths;the second is the correspondence of distributions between sea surface temperature,850 hPa zonal wind(u),meridional wind(v),and 500 hPa potential height field;and the third is the numerical sensitivity experiment,which reflects the evident impact of variations in the physical field around the typhoon to the WPSH index.Secondly,the model is repeatedly trained through the backward propagation algorithm to predict the WPSH index using 2011–2018 atmospheric variables as the input of the training set.The model predicts the WPSH index after 6 h,24 h,48 h,and 72 h.The validation set using independent data in 2019 is utilized to illustrate the performance.Finally,the model is improved by changing the CNN2D module to the DeCNN module to enhance its ability to predict images.Taking the 2019 typhoon“Lekima”as an example,it shows the promising performance of this model to predict the 500 hPa potential height field. 展开更多
关键词 WPSH index TYPHOON hybrid deep learning model PREDICTORS numerical sensitivity experiment
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Hybrid Long-Period Fiber Grating with Multimode Fiber Core for Refractive Index Measurement
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作者 邵敏 乔学光 +1 位作者 任学良 杨德兴 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第11期41-44,共4页
A refractive index (RI) sensor based on hybrid long-period fiber grating (LPFG) with multimode fiber core (MMFC) is proposed and demonstrated. The surrounding RI can be determined by monitoring the separation be... A refractive index (RI) sensor based on hybrid long-period fiber grating (LPFG) with multimode fiber core (MMFC) is proposed and demonstrated. The surrounding RI can be determined by monitoring the separation between the resonant wavelengths of the LPFG and MMFC since the resonant wavelengths of the LPFG and MMFC will shift in opposite directions when the surrounding RI changes. Experimental results show that the sensor possesses an enhanced sensitivity of 526.92nm/RIU in the RI range of 1.387-1.394 RIU. The response to the temperature is also discussed. 展开更多
关键词 hybrid Long-Period Fiber Grating with Multimode Fiber Core for Refractive index Measurement RIU
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A hybrid algorithm for reengineering the refractive index profile of inhomogeneous coatings from optical in-situ broadband monitoring data
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作者 S. Wilbrandt O. Stenzel +1 位作者 D. Gbler N. Kaiser 《光学精密工程》 EI CAS CSCD 北大核心 2005年第4期487-491,共5页
Reengineering the refractive index profile of inhomogeneous coatings is a troublesome task. Multiplicity of solutions may significantly reduced by providing additional information. For this reason an in-situ broadband... Reengineering the refractive index profile of inhomogeneous coatings is a troublesome task. Multiplicity of solutions may significantly reduced by providing additional information. For this reason an in-situ broadband monitoring system was developed to measure the transmittance of the growing film directly at the rotating substrate. For characterization of these coatings, a new model was developed, which significantly reduces the number of parameters. The refractive index profile may be described by a proper number of equally spaced volume fraction values using the Bruggeman effective media approach. A good initial approximation of the refractive index profile can be generated based on deposition rates for both materials recorded with quartz crystal monitor during manufacturing. During the optimization process, a second order minimization algorithm was used to vary the refractive index profile of the whole coating and film thickness of the intermediate stages. Finally, a significantly improved accuracy of the modelled transmittance was achieved. 展开更多
关键词 光学涂覆技术 折射率 宽带 混合模型 管理方式
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面向科技文献多维语义组织的混合倒排索引构建方法
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作者 张敏 李唯 范青 《现代情报》 北大核心 2024年第2期107-114,129,共9页
[目的/意义]为满足科研人员对科技文献内部细粒度语义信息进行高效查询的迫切需求,前期研究提出了面向科技文献的多维语义索引体系,然而基于HashMap的常见倒排索引会导致查询效率低下。本文旨在通过面向不同维度语义特征建立混合倒排索... [目的/意义]为满足科研人员对科技文献内部细粒度语义信息进行高效查询的迫切需求,前期研究提出了面向科技文献的多维语义索引体系,然而基于HashMap的常见倒排索引会导致查询效率低下。本文旨在通过面向不同维度语义特征建立混合倒排索引,以改进语义查询性能。[方法/过程]本文以Treap、B+树等多种数据结构探索适合不同语义维度的倒排索引构建方法,并将其组合形成多种适用于科技文献多维语义组织的混合倒排索引构建方法,并通过对比实验,在排序查询和布尔查询条件下分析验证不同类型倒排索引构建方法的查询性能。[结果/结论]实验结果表明,组合形成的8种混合倒排索引构建方法中,表2所示的C3(HHHB)被证明在排序查询条件下具有最高的效率,而C4(TTTB)则在布尔查询条件下被证明最为高效。本文的方法能有效解决单一索引结构导致的查询效率问题。 展开更多
关键词 科技文献 语义组织 混合倒排索引 HashMap Treap B+树
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基于二维混合式位置编码的高精度测角
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作者 赵会宁 闻杰 夏豪杰 《光学精密工程》 EI CAS CSCD 北大核心 2024年第5期635-642,共8页
针对具有精密旋转轴系类的高端制造装备或精密测量仪器,其旋转角度采用传统圆光栅难以消除偏心误差对测量角度精度的影响,提出了一种基于二维混合式位置编码的旋转角度高精度测量方法。该测角系统由一个二维混合式位置编码盘、两个CCD... 针对具有精密旋转轴系类的高端制造装备或精密测量仪器,其旋转角度采用传统圆光栅难以消除偏心误差对测量角度精度的影响,提出了一种基于二维混合式位置编码的旋转角度高精度测量方法。该测角系统由一个二维混合式位置编码盘、两个CCD相机和远心镜头组成,二维混合式位置编码盘被固定在精密旋转轴系上以获得其旋转角度。然后,建立了测角模型并从数学上证明了测角精度与安装偏心无关。利用多齿分度台对已提出测角系统精度进行检测,测量角度误差在±1″。最后,利用已提出测量方法对直驱转台的角度定位精度进行测量,角度定位误差在±5″内。与传统圆光栅测角相比,该方法不需要考虑安装偏心误差对测角精度的影响,具有稳定性好、使用简单等特点,可用于角度定位误差的检测。 展开更多
关键词 二维混合式位置编码 偏心误差 旋转角度 多齿分度台
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基于改进变分模态分解和优化堆叠降噪自编码器的轴承故障诊断
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作者 张彬桥 舒勇 江雨 《计算机集成制造系统》 EI CSCD 北大核心 2024年第4期1408-1421,共14页
针对滚动轴承在噪声干扰下故障特征难以提取的问题,提出一种改进变分模态分解(VMD)和复合缩放排列熵(CZPE)的特征提取新方法,并利用优化堆叠降噪自编码器(SDAE)进行故障分类。首先,提出由“余弦相似度—峭度—包络熵”新综合评价指标自... 针对滚动轴承在噪声干扰下故障特征难以提取的问题,提出一种改进变分模态分解(VMD)和复合缩放排列熵(CZPE)的特征提取新方法,并利用优化堆叠降噪自编码器(SDAE)进行故障分类。首先,提出由“余弦相似度—峭度—包络熵”新综合评价指标自适应优化分解参数的改进VMD方法,并通过该指标筛选分解后的本征模态函数(IMF)分量;然后,为提取更全面的故障特征,引入新的复合缩放排列熵对各有效IMF的故障特征进行量化;最后,提出一种基于鼠群优化算法(RSO)与麻雀搜索算法(SSA)的混合算法优化SDAE网络超参数,将故障特征输入优化后SDAE网络中得到分类结果。采用美国CWRU轴承数据集进行验证,实验结果表明该方法能全面稳定地提取背景噪声下的故障特征,且与其他方法相比具有更好的抗噪性能和更高的故障诊断准确率。 展开更多
关键词 变分模态分解 综合评价指标 复合缩放排列熵 混合算法 堆叠降噪自编码器
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多花指甲兰开花特性与繁育系统研究
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作者 郑棚汭 董春燕 +8 位作者 陈之光 徐言 葛红 杨树华 赵鑫 寇亚平 朱晋宇 贾瑞冬 武荣花 《浙江农林大学学报》 CAS CSCD 北大核心 2024年第1期124-131,共8页
【目的】研究多花指甲兰Aerides rosea的开花特性与繁育系统,为多花指甲兰的种质资源保护提供理论依据。【方法】观察记录温室栽培条件下多花指甲兰的花部特征和开花进程,检测花粉活力与柱头可授性,估算杂交指数(OCI)及进行人工控制授... 【目的】研究多花指甲兰Aerides rosea的开花特性与繁育系统,为多花指甲兰的种质资源保护提供理论依据。【方法】观察记录温室栽培条件下多花指甲兰的花部特征和开花进程,检测花粉活力与柱头可授性,估算杂交指数(OCI)及进行人工控制授粉试验。【结果】①多花指甲兰5—7月开花,开放时有香味,单株花期约15 d,单花花期约10 d。花蕾期为开花前1-5 d,初花期为开花后1-4 d,盛花期为开花后5-6 d,末花期为开花后7-8 d,凋谢期为开花后9-10 d。②总状花序,有1-4个花序,花序较长,密生数十朵花,整株花期一致。③在花蕾期,花朵还未开放时花粉已具备活力,部分柱头具备可授性;花粉活力与柱头可授性在盛花期(开花5-6 d)达到峰值。多花指甲兰的OCI为4。④无论是否去雄、套袋,不进行人工授粉的结实率均为0,而人工自花授粉、同株异花授粉和异株异花授粉的结实率分别为85.71%、88.00%、84.00%,均高于不进行人工授粉的植株。【结论】多花指甲兰自5月初开花至7月底结束,盛花期较短,持续约2 d。多花指甲兰不存在无融合生殖现象,是需要传粉者传粉的自交和异交混合的繁育系统。 展开更多
关键词 多花指甲兰 开花进程 花粉活力 柱头可授性 繁育系统 杂交指数
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香水莲花开花过程中花色变化规律研究
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作者 周琦 赵峰 +2 位作者 张慧会 祝遵凌 汤鹏 《热带作物学报》 CSCD 北大核心 2024年第1期122-133,共12页
香水莲花(Nymphaea hybrid)是睡莲属中的大型热带睡莲,与目前常见睡莲不同,其花期长,花型优美,花色丰富,花香怡人,富含生物活性物质,受到越来越多研究者的关注。不同品系香水莲花花色随花期变化存在差异,而其花色变化规律尚不明确。本... 香水莲花(Nymphaea hybrid)是睡莲属中的大型热带睡莲,与目前常见睡莲不同,其花期长,花型优美,花色丰富,花香怡人,富含生物活性物质,受到越来越多研究者的关注。不同品系香水莲花花色随花期变化存在差异,而其花色变化规律尚不明确。本研究以4种不同花色香水莲花在不同花期的外层花瓣为试材,测定其在开花过程中花瓣色度值、花青苷、黄酮、细胞液pH、可溶性糖(soluble sugar,SS)和可溶性蛋白(soluble protein,SP)含量,苯丙氨酸解胺酶(phenylalanineammonialyase,PAL)和查尔酮异构酶(chalconeisomerase,CHI)的活性变化,以探讨香水莲花花色变化规律。结果表明:(1)香水莲花大多数花瓣表皮细胞都呈不规则褶皱突起,紫色、粉色和黄色香水莲花的色素主要分布于上、下表皮细胞,白色香水莲花中几乎未见色素分布;(2)随着花期的推移,总花青苷(total anthocyanin,TA)含量、PAL和CHI活性呈降低趋势,细胞液pH逐渐上升,总黄酮(total flavonoids,TF)、SS和SP含量先增加后降低,而花瓣明度L^(*)增强,且不同花期各参数值之间差异显著;(3)花瓣总花青苷与L^(*)、细胞液pH呈显著负相关,而与PAL、CHI酶活性呈极显著正相关关系。这表明香水莲花花色变化受多因素共同影响,花色的呈现与花瓣形态及花色素分布的位置等有关,花瓣花青苷和黄酮类物质含量的高低直接影响其花色的深浅,PAL和CHI酶活性一定程度上对香水莲花的花色形成起促进作用;同时pH、SS和SP则通过参与开花过程中的生理代谢,影响香水莲花花色的形成及其稳定性,进而导致香水莲花花色色调的改变。 展开更多
关键词 香水莲花 花色变化 花青苷 黄酮 生理指标
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玉米杂交种耐盐碱性的主成分分析及综合评价
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作者 伏晓昭 佘奎军 +1 位作者 程晋龙 杨国虎 《甘肃农业大学学报》 CAS CSCD 北大核心 2024年第1期65-73,共9页
【目的】筛选适合宁夏引黄灌区盐碱化土壤种植的耐盐碱玉米杂交种。【方法】采用宁夏农科院选育的30份玉米杂交种株高、穗位高、茎粗、穗长、穗粗、单穗质量、出苗率等14个性状指标,基于主成分分析和聚类分析综合筛选耐盐碱玉米杂交种... 【目的】筛选适合宁夏引黄灌区盐碱化土壤种植的耐盐碱玉米杂交种。【方法】采用宁夏农科院选育的30份玉米杂交种株高、穗位高、茎粗、穗长、穗粗、单穗质量、出苗率等14个性状指标,基于主成分分析和聚类分析综合筛选耐盐碱玉米杂交种。【结果】主成分分析结果表明,将14农艺性状转化成5个主成分因子,代表原始数据信息量85.57%,并选出单穗质量、穗行数、出籽率、茎粗、出苗率5个耐盐碱评价指标;宁禾1822、宁禾2021、宁禾1948、宁禾2035和先玉1225这5份玉米杂交种耐盐碱性较好。聚类分析将30份耐盐碱品种分为3种类型,结果与主成分分析基本一致。【结论】通过2种分析方法筛选出5份耐盐碱性较强的杂交种,给宁夏平罗盐碱地玉米种植提供理论参考。 展开更多
关键词 玉米杂交组合 耐盐碱性 性状指标 主成分分析 聚类分析
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践踏对5个植丝深度高羊茅草坪生理指标的影响
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作者 刘亚培 周升峰 +6 位作者 李昶仪 毛佳静 刘月月 韩翔劲 李进超 张馨月 许立新 《草业科学》 CAS CSCD 北大核心 2024年第7期1624-1631,共8页
为了解践踏对不同植丝深度草坪草生理指标的影响,本研究以高羊茅(Festuca arundinacea)植丝式混合草坪为试验对象,设置5种不同人造草丝深度6、9、12、15、18 cm和不植丝(CK),通过模拟践踏处理的方式,对比研究5种植丝深度混合草坪与天然... 为了解践踏对不同植丝深度草坪草生理指标的影响,本研究以高羊茅(Festuca arundinacea)植丝式混合草坪为试验对象,设置5种不同人造草丝深度6、9、12、15、18 cm和不植丝(CK),通过模拟践踏处理的方式,对比研究5种植丝深度混合草坪与天然草坪在践踏胁迫下草坪草的坪观质量、生理指标以及践踏后草坪草的恢复状况。未践踏情况下,植丝深度18 cm草坪质量显著高于对照和其他深度植丝处理,随着践踏次数增加,其他各深度植丝处理也对草坪质量有一定提升作用。植丝15 cm处理高羊茅叶绿素含量均能更快恢复,9 cm以上处理组在抑制丙二醛含量、可溶性蛋白和抗氧化酶活性恢复方面均有优势。综合试验结果表明,践踏胁迫条件下植丝式混合草坪的坪观质量总体表现高于天然草坪,植入人造草丝深度9 cm以上能在不同指标上有效加强草坪草抵抗践踏胁迫的能力,提升草坪草践踏后恢复速率。本研究为植丝式混合草坪的技术探索及应用推广提供了理论和实践依据。 展开更多
关键词 植丝式混合草坪 草坪质量 运动性能 归一化植被指数 叶绿素含量 丙二醛含量 抗氧化酶活性
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基于VMD-WOA混合多尺度分解的区间组合预测模型
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作者 康晓晓 陈华友 +1 位作者 韩冰 胡彦 《武汉理工大学学报(信息与管理工程版)》 CAS 2024年第3期460-466,共7页
针对传统的点预测模型难以适用于随机性复杂系统和非线性非平稳时间序列预测的问题,提出基于VMD-WOA混合多尺度分解的区间组合预测模型。首先,引入基于鲸鱼优化(WOA)的变分模态分解(VMD)混合分解算法,得到最优区间模态子序列;其次,对各... 针对传统的点预测模型难以适用于随机性复杂系统和非线性非平稳时间序列预测的问题,提出基于VMD-WOA混合多尺度分解的区间组合预测模型。首先,引入基于鲸鱼优化(WOA)的变分模态分解(VMD)混合分解算法,得到最优区间模态子序列;其次,对各区间模态分序列使用指数平滑方法(Holt′s)、支持向量回归(SVR)和BP神经网络预测,得到3个单项预测结果,运用组合预测模型得到模态组合子序列;最后,对模态组合子序列重构,得到最终的区间组合预测序列。为了验证模型的有效性,选取AQI数据进行预测分析,实验表明所提出的基于VMD-WOA的区间组合预测方法具有较高的预测精度和良好的适应性。 展开更多
关键词 混合多尺度分解 变分模态分解(VMD) 鲸鱼优化(WOA) 区间组合预测 空气质量指数
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乳腺癌患者螺旋断层放疗与混合调强放疗治疗效果探讨
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作者 陈泽杰 高梦圆 +1 位作者 林勤 柯瑞全 《中国卫生标准管理》 2024年第3期92-95,共4页
目的探讨螺旋断层放射治疗(helical tomotherapy,TomoHelical)与混合调强放射治疗(hybrid intensity modulated radio-therapy,Hy-IMRT)2种治疗方式对早期乳腺癌保乳手术患者的影响。方法随机选取厦门大学附属第一医院肿瘤放射治疗科202... 目的探讨螺旋断层放射治疗(helical tomotherapy,TomoHelical)与混合调强放射治疗(hybrid intensity modulated radio-therapy,Hy-IMRT)2种治疗方式对早期乳腺癌保乳手术患者的影响。方法随机选取厦门大学附属第一医院肿瘤放射治疗科2023年1—7月保乳乳腺癌手术早期患者50例,并按术后射线治疗方式的不同分为TOMO组与Hy-IMRT组,各25例。比较2种治疗方式照射靶区处处方剂量(planning target volume,PTV)的剂量学参数及放疗后周围正常器官剂量学,放疗结束随访3个月并比较其预后情况。结果与Hy-IMRT相比,TOMO治疗的PTV符合性指数(conformity index,CI)为(0.68±0.15),均匀性指数(homogeneity index,HI)为(1.09±0.12),Hy-IMRT治疗治疗的PTV CI为(0.54±0.12),HI为(1.37±0.17),差异有统计学意义(P<0.05)。TOMO组全肺平均放射剂量(mean does,Dmean)为(517.23±109.33)cGy,全肺受到5 Gy或以上的辐射剂量的体积百分比(volume5,V5)为(18.53±4.07)%,全肺受到20 Gy或以上的辐射剂量的体积百分比(volume20,V20)为(10.55±2.83)%,Hy-IMRT组全肺平均放射剂量(mean does,Dmean)为(581.12±113.72)cGy,全肺受到5 Gy或以上的辐射剂量的体积百分比(volume5,V5)为(21.44±4.85)%,及全肺受到20 Gy或以上的辐射剂量的体积百分比(volume20,V20)为(12.66±3.15)%,TOMO组均低于Hy-IMRT组(P<0.05)。TOMO组心脏Dmean为(521.44±86.72)cGy,Hy-IMRT组心脏Dmean为(577.14±96.33)cGy,TOMO组低于Hy-IMRT组(P<0.05)。结论对早期乳腺癌保乳手术患者实施TOMO计划治疗,可以有效提升肿瘤靶区剂量分布的均匀性,对周围正常组织器官损害较小,但仍需更多临床数据来支持。 展开更多
关键词 保乳乳腺癌手术患者 螺旋断层放疗 混合调强放疗 符合性指数 均一性指数 危及器官
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考虑灵活性的交直流混联配电网分布鲁棒优化运行
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作者 张振强 王宏波 +3 位作者 赵阳 范岳 李雪晴 艾欣 《电力科学与技术学报》 CAS CSCD 北大核心 2024年第2期64-73,共10页
为适应未来配电网交直流混联的配电方式、应对新能源不确定性带来的运行灵活性调节量不足问题,提出一种考虑灵活性的交直流混联配电网两阶段分布鲁棒优化运行模型。首先,在交直流混联配电网架构下,分析其灵活性资源供需关系,定义上调/... 为适应未来配电网交直流混联的配电方式、应对新能源不确定性带来的运行灵活性调节量不足问题,提出一种考虑灵活性的交直流混联配电网两阶段分布鲁棒优化运行模型。首先,在交直流混联配电网架构下,分析其灵活性资源供需关系,定义上调/下调灵活性裕度指标;其次,综合考虑系统中各类约束,构建描述配电网经济性、新能源消纳性与灵活性的优化运行模型,结合数据驱动生成的风光典型场景,采用基于综合范数距离的分布鲁棒优化方法处理风、光出力不确定性,并根据优化变量的出力特性构建两阶段分布鲁棒优化运行模型;最后,对模型进行凸性转化与求解,通过修改的33节点交直流混联配电网算例验证模型的有效性。 展开更多
关键词 交直流混联配电网 新能源不确定性 灵活性裕度指标 两阶段分布鲁棒优化
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