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化工设备设计 1999年第2期36卷 20-23页

作者：徐至钧北京恒富集团公司北京100070

本文对塔型设备自振周期进行探讨，将现有常用理论公式的计算结构与实测进行对比，然后根据100台落地塔的实测周期，采用数理统计分析，提出计算自振周期的经验公式，并对经验公式作了分析。

关键词：塔设备实测周期统计分析自振周期

旋转二维光晶格中玻色-爱因斯坦凝聚体量子涡旋研究

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量子电子学报 2016年第6期33卷 697-703页

作者：季程超徐志君浙江工业大学应用物理系浙江杭州310023

基于Gross Pitaevskii(G-P)方程的数值模拟,研究了旋转二维光晶格中玻色-爱因斯坦凝聚气体量子涡旋的动力学性质,分析了光晶格常数d、光晶格深度v_0对量子涡旋的影响。结果表明:随v_0增加量子涡旋形成过程变快,通过计算系统自由能随时... 详细信息

基于Gross Pitaevskii(G-P)方程的数值模拟,研究了旋转二维光晶格中玻色-爱因斯坦凝聚气体量子涡旋的动力学性质,分析了光晶格常数d、光晶格深度v_0对量子涡旋的影响。结果表明:随v_0增加量子涡旋形成过程变快,通过计算系统自由能随时间的演化分析了这一动力学行为的物理本质;v_0大于50时出现针钉效应,即量子涡旋被光晶格固定在势能极值点;d大于2.7d_c(d_c为临界常数)时出现涡旋-反涡旋对.

关键词：量子光学量子涡旋 Gross-Pitaevskii方程临界光晶格常数

Artificial intelligence for celestial object census:the latest technology meets the oldest science

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Science Bulletin 2021年第21期66卷 2145-2147,M0003页

作者： Baoqiang Lao Tao An Ailing Wang zhijun xu Shaoguang Guo Weijia Lv Xiaocong Wu Yingkang Zhang Shanghai Astronomical Observatory Key Laboratory of Radio AstronomyChinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049.China

Astronomy is the oldest natural science based on observation,and a census of objects in the sky map to create a catalog is the basis for further *** effort is achieved through astronomical object detection,also known as"source finding",which aims to identify individual objects in an astronomical image and then retrieve the properties of those objects to form a *** completeness,reliability,and accuracy of the resulting catalog has a profound impact on astrophysical research.

关键词：人工智能 individual image

Genetic analysis and fine mapping of a grain size QTL in the smallgrain sterile rice line Zhuo201S

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Journal of Integrative Agriculture 2024年第7期23卷 2155-2163页

作者： Bin Lei Jiale Shao Feng Zhang Jian Wang Yunhua Xiao zhijun Cheng Wenbang Tang Jianmin Wan College of Agronomy Hunan Agricultural UniversityChangsha 410128China National Key Facility for Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081China State Key Laboratory for Crop Genetics and Germplasm Enhancement/Jiangsu Plant Gene Engineering Research Center Nanjing Agricultural UniversityNanjing 210095China State Key Laboratory of Hybrid Rice Hunan Hybrid Rice Research CenterChangsha 410125China

The development and application of the small-grain rice sterile line Zhuo201S(Z201S)has demonstrated its potential for mechanized hybrid rice seed production,leading to significant cost ***,the molecular mechanism responsible for the small-grain size characteristic of Z201S remains *** this study,we conducted a genetic analysis using near-isogenic lines constructed from Z210S,a small-grain rice sterile line,and R2115,a normal-grain *** results revealed that the small-grain trait in Z201S is governed by a single partially dominant gene which also enhances grain *** mapping,we localized the causal gene to the short arm of chromosome 2,within a 113 kb physical region delimited by the molecular markers S2-4-1 and *** analysis and gene expression assays indicated LOC_Os02g14760 as the most likely candidate gene,suggesting that the small-grain size trait of Z201S is controlled by a novel locus that has not been previously identified.

关键词： rice grain size map-based cloning

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基于回归分析的绝对式光栅尺精度提高方法

华中科技大学学报（自然科学版） 2015年第1期43卷 21-23,79页

作者：乔栋续志军吴宏圣曾琪峰中国科学院长春光学精密机械与物理研究所吉林长春130033 中国科学院大学北京100049

提出一种使用回归分析提高绝对式光栅尺测量精度的方法.分析了影响绝对式光栅尺测量精度的因素以及提高其测量精度的方法;对JC09型绝对式光栅尺的测量值和真值进行回归分析,得到回归方程;对回归方程进行了显著性分析,并提出了修正方程;... 详细信息

提出一种使用回归分析提高绝对式光栅尺测量精度的方法.分析了影响绝对式光栅尺测量精度的因素以及提高其测量精度的方法;对JC09型绝对式光栅尺的测量值和真值进行回归分析,得到回归方程;对回归方程进行了显著性分析,并提出了修正方程;通过实验验证了该方法能够有效提高绝对式光栅尺的测量精度.实验结果表明：在绝对式光栅尺800mm测量长度内,测量精度由0∽18.25μm提高到-4.21∽5.72μm.另外,该方法具有成本低、计算量少以及易于实现的优点.

关键词：测量回归分析绝对式光栅尺精度误差补偿

Modulation of starch digestibility using non-thermal processing techniques:A review

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Grain & Oil Science and Technology 2024年第3期7卷 209-218页

作者： Liyuan Rong Weiqi Fei zhijun Wang Xianxiang Chen Huiliang Wen Jianhua Xie Mingyue Shen State Key Laboratory of Food Science and Resources Nanchang UniversityNanchang 330047China School of Biosystems and Food Engineering University College DublinDublinIreland

Obesity and type 2 diabetes are widespread throughout the world, especially in developed countries. Starch is an important part of human staple food, the modulating of starch digestibility is conducive to reducing postprandial blood glucose levels and alleviating the chronic disease caused by high caloric intake. The digestion properties of starch are correlated with its structural features, including crystallization, amylose/amylopectin ratio, non-starch components, etc. Among the modified methods applied to regulate starch digestibility, non-thermal processing techniques(NTPT) receive extensive attention due to the characteristics of safety, environmental friendliness and high efficiency. The influence and mechanism of NTPT on the digestion properties of starch are discussed in this review, including ultrasounds, high pressure, γ-irradiation, etc. NTPT induces the alternation of morphological and structural characteristics of native starch, changing their sensitivity to enzymes. The effects of NTPT on the digestibility of starch are highly related to the processing parameters and structure characteristics of native starch. The review shows that NTPT is an effective way to modulate the digestion properties of starch and prevent people from suffering from chronic diseases such as obesity and type 2 diabetes.

关键词： Digestibility Non-thermal processing Chronic disease Starch

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海南山栏稻品种全生育期抗旱性鉴定与评价

热带作物学报 2018年第1期39卷 55-60页

作者：徐建欣杨洁徐志军中国热带农业科学院湛江实验站热带旱作农业研究中心广东湛江524013

以筛选优质抗旱山栏稻种质资源为研究目的,利用陆稻全生育期综合抗旱性鉴定体系对22个海南山栏稻品种进行抗旱性鉴定与评价。结果表明:海南山栏稻品种不同生育期间所表现出的抗旱能力具有极显著的正相关关系;山栏糯(黄壳)(编号1、4、6... 详细信息

以筛选优质抗旱山栏稻种质资源为研究目的,利用陆稻全生育期综合抗旱性鉴定体系对22个海南山栏稻品种进行抗旱性鉴定与评价。结果表明:海南山栏稻品种不同生育期间所表现出的抗旱能力具有极显著的正相关关系;山栏糯(黄壳)(编号1、4、6、18、22)等5个品种在全生育期均表现出高抗旱能力。此结果为开展山栏稻抗旱新品种选育及优异抗旱基因挖掘等工作提供重要的实验材料,同时说明海南山栏稻群体中蕴含丰富的抗旱遗传种质资源,应加强山栏稻种质资源的收集保护及评价鉴定工作。

关键词：山栏稻种质资源全生育期抗旱性鉴定评价

基于改进的带监督流形学习算法的通信电台识别

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解放军理工大学学报（自然科学版） 2013年第5期14卷 479-483页

作者：王金明徐玉龙徐志军解放军理工大学通信工程学院江苏南京210007

设计了一种电台主域积分双谱(PIB)特征参数提取方法,利用双谱特征的对称性,简化计算,提高计算效率。针对PIB特征参数冗余仍然较大,导致分类器复杂、识别效率低的问题,提出了一种改进的带监督局部线性嵌入(LLE)流形学习方法,利用电台数... 详细信息

设计了一种电台主域积分双谱(PIB)特征参数提取方法,利用双谱特征的对称性,简化计算,提高计算效率。针对PIB特征参数冗余仍然较大,导致分类器复杂、识别效率低的问题,提出了一种改进的带监督局部线性嵌入(LLE)流形学习方法,利用电台数据类别信息的监督距离改进LLE算法中的邻域点搜索方法,并用于PIB参数的降维。将上述方法用于电台个体识别,采用概率神经网络作为识别分类器,对同型号同工作参数的10部电台进行个体识别实验。实验结果验证了上述方法的有效性,在接收信号信噪比为20dB时电台的正确识别率超过90%。

关键词：电台识别主域积分双谱局部线性嵌入主成分分析

Exposure Patterns of Multiple Pesticides and Urinary Alterations of Trimethylamine(TMA)and Trimethylamine N‑Oxide(TMAO)among Pregnant Women

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Environment & Health 2024年第3期2卷 126-139页

作者： Jiayun Ding Yiming Dai Zheng Wang Boya Zhang Sinan xu Jianqiu Guo Xiaojuan Qi Dasheng Lu Xiuli Chang Chunhua Wu Jiming Zhang zhijun Zhou Key Laboratory of Public Health Safety of Ministry of Education Key Laboratory of Health Technology Assessment of National Health CommissionSchool of Public HealthFudan UniversityShanghai 200032China Shanghai Municipal Center for Disease Control and Prevention Shanghai 200336China

Environmental exposure to pesticides is widespread and commonly occurs in mixtures,and pregnant women are particularly *** N-oxide(TMAO),a dietary-derived catabolite linked to cardiometabolic disease,may be influenced by pesticide ***,limited knowledge exists regarding the associations,and studies have primarily been restricted to single *** address this gap,we examined the associations of pesticide exposure with urinary TMA,TMAO,and TMAO-to-TMA ratio among 1067 pregnant women residing in a rural *** class analysis(LCA)was applied to identify distinct patterns of pesticide exposure based on urinary metabolite *** linear regression(MLR)models and Bayesian kernel machine regression(BKMR)models were employed to estimate the effects of single pesticides,exposure patterns,and combined *** distinct pesticide exposure patterns were *** concentrations of pesticide metabolites were found to be associated with increased urinary TMAO levels(β:0.043 to 0.254,p<0.05).In the MLR models for individual pesticides and exposure patterns,carbofuran phenol(CFP),pentachlorophenol(PCP),and 2-phenylphenol(OPP)exhibited positive associations with urinary TMA concentrations,while pyrethroid pesticide metabolites were correlated with the up-regulation of the TMAO-to-TMA *** positive associations of pesticide mixtures with TMA,TMAO,and TMAO-to-TMA ratio were observed in the BKMR model,primarily driven by PCP and *** findings provided a perspective to reveal that the mechanisms and contributions to TMAO alterations may vary among different pesticides in mixture exposure.

关键词： pesticide exposure trimethylamine trimethylamine N-oxide exposure patterns mixture exposure

Non-diffracting integer-order and half-integer-order carpet beams obtained by even-type sinusoidal amplitude radial gratings

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Chinese Optics Letters 2024年第7期22卷 86-92页

作者： Yefeng Liu Huiqing Li Rijian Chen Changjiang Fan Yile Shi zhijun Ren Key Laboratory of Optical Information Detecting and Display Technology Zhejiang Normal UniversityJinhua 321004China

In this work,we introduce a kind of new structured radial grating,which is named the even-type sinusoidal amplitude radial(ETASR)*** on diffraction theory and the principle of stationary phase,a comprehensive theoretical investigation on the diffraction patterns of ETASR gratings is *** results show that novel carpet beams with beautiful optical structures and distinctive characteristics have been constructed on the basics of the ETASR *** diffraction patterns are independent of propagation distance,that is,the new carpet beams have diffraction-free propagating *** non-diffracting carpet beams are divided into two types by beam characteristics:non-diffracting integer-order and half-integer-order carpet ***,we experimentally generate these carpet beams using the ETASR ***,their particularly interesting optical morphology and features are explored through numerical simulations and experiments.

关键词： even-type sinusoidal amplitude radial gratings principle of stationary phase non-diffracting integer-order carpet beams non-diffracting half-integer-order carpet beams