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UWLPIPE:Ultra-wide Bandwidth Low-frequency Pulsar Data Processing Pipeline

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Research in Astronomy and Astrophysics 2024年第7期24卷 145-157页

作者： Ya-Zhou Zhang Hai-Long Zhang Jie Wang Jian Li Xin-Chen Ye Shuang-Qiang Wang Xu Du Han Wu ting Zhang Shao-Cong guo Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China National Astronomical Data Center Beijing 100101China Southeast University Nanjing 211189China

For real-time processing of ultra-wide bandwidth low-frequency pulsar baseband data,we designed and implemented an ultra-wide bandwidth low-frequency pulsar data processing pipeline(UWLPIPE)based on the shared ringbuffer and GPU parallel *** runs on the GPU cluster and can simultaneously receive multiple 128 MHz dual-polarization VDIF data packets preprocessed by the front-end *** aligning the dual-polarization data,multiple 128M subband data are packaged into PSRDADA baseband data or multi-channel coherent dispersion filterbank data,and multiple subband filterbank data can be spliced into wideband data after time *** used the Nanshan 26 m radio telescope with the L-band receiver at964~1732 MHz to observe multiple ***,we processed the data using DSPSR software,and the results showed that each subband could correctly fold out the pulse profile,and the wideband pulse profile accumulated by multiple subbands could be correctly aligned.

关键词： (stars)pulsars general-methods data analysis-techniques miscellaneous

玉米近红外光谱在仿生模式识别中的特征提取方法研究

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光谱学与光谱分析 2012年第4期32卷 939-943页

作者：沈立峰贾仕强郭婷婷邬文锦严衍禄安冬中国农业大学信息与电气工程学院北京100083 中国农业大学国家玉米改良中心北京100193

近红外光谱特征提取是近红外光谱定性分析的关键步骤,其质量直接影响定性分析结果。采用漫透射方法测量8个玉米品种的近红外光谱,经预处理后,分别采用PCA,ICA,PLS-DA和小波分解四种方法对光谱进行特征提取,并使用仿生模式识别方法建立了... 详细信息

近红外光谱特征提取是近红外光谱定性分析的关键步骤,其质量直接影响定性分析结果。采用漫透射方法测量8个玉米品种的近红外光谱,经预处理后,分别采用PCA,ICA,PLS-DA和小波分解四种方法对光谱进行特征提取,并使用仿生模式识别方法建立了8个玉米品种识别模型,最后使用测试集数据进行模型测试。结论如下:使用PLS-DA方法进行特征提取后建立的模型正确识别率优于使用PCA,ICA和小波分解特征提取后建立的模型。

关键词：玉米品种近红外光谱仿生模式识别特征提取漫透射

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不同形状气膜孔对气膜冷却效果的影响

动力工程 2006年第3期26卷 333-336页

作者：郭婷婷刘建红宋东辉李少华东北电力大学吉林132012

采用RNGk-ε湍流模型对扇形角(锥形角)γ为30°的垂直扇形气膜冷却单孔射流流场下游的流动和传热特性进行了详细的数值模拟,并将沿程方向的速度分布、相同吹风比下的冷却效率与相同条件下圆孔射流的计算结果进行了比较分析。结果表明:... 详细信息

采用RNGk-ε湍流模型对扇形角(锥形角)γ为30°的垂直扇形气膜冷却单孔射流流场下游的流动和传热特性进行了详细的数值模拟,并将沿程方向的速度分布、相同吹风比下的冷却效率与相同条件下圆孔射流的计算结果进行了比较分析。结果表明:射流轨迹对横向主气流的影响主要集中在射流发生弯曲直至与主气流平行的区域内;喷孔为圆孔时,吹风比越小,射流中心线越靠近壁面,其冷却效率越好;吹风比相同,扇形喷孔的冷却效率高于圆孔的冷却效率;扇形孔的冷却效率并不随吹风比的变化而单调变化,而是在吹风比为1.0时存在最佳值。

关键词：动力机械工程涡轮机械气膜冷却紊动射流数值模拟冷却效率

Recent progress of two-dimensional metal-base catalysts in urea oxidation reaction

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Rare Metals 2024年第8期43卷 3607-3633页

作者： Qi-Xiang Huang Fang Wang Yong Liu Bi-Ying Zhang Fang-Ya guo Zhong-Qiu Jia Hao Wang Tian-Xiang Yang Hai-Tao Wu Feng-Zhang Ren ting-Feng Yi School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471000China School of Environmental Engineering and Chemistry Luoyang Institute of Science and TechnologyLuoyang 471023China Henan Province International Joint Laboratory of Materials for Solar Energy Conversion and Lithium Sodium Based Battery Luoyang 471023China School of Chemistry and Life Sciences Suzhou University of Science and TechnologySuzhou 215009China School of Materials Science and Engineering Northeastern UniversityShenyang110819China

Urea oxidation reaction(UOR)is an auxiliary water electrolysis hydrogen production technology developed in recent years to replace oxygen evolution reaction and reduce energy consumption,which can produce hydrogen more efficiently by low theoretical potential,reduce the average cost of electrochemical hydrogen production,and is a frontier research hotspot for renewable hydrogen ***-dimensional(2D)nanomaterials as electrocatalysts have many favorable potential,such as it can effectively reduce the resistivity of materials and increase the specific surface area with *** paper reviews the application of 2D materials in UOR in alkaline *** a cross-sectional comparison of various material performance data including overpotential,Tafel slope,electrochemical active surface area(ECSA)and it stability test was conducted,which could illustrate the differences between materials composed of different *** addition,the main challenges hindering the progress of research on 2D materials in urea electrocatalysis processes and promising materials in this field in future are summarized and *** is believed that this review will contribute to designing and analyzing highperformance 2D urea electrocatalysts for water splitting.

关键词： Water splitting Urea oxidation reaction Two-dimensional Transition metal compounds Noble/non-noble metals

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扇形喷孔气膜冷却流场的大涡模拟

动力工程 2008年第2期28卷 185-189页

作者：郭婷婷邹晓辉刘建红李少华东北电力大学能源与机械工程学院吉林132012

对锥形角γ=30°扇形喷孔横向紊动射流进行了大涡模拟，在吹风比M=1．0工况下模拟了不同截面上涡量随时间变化的过程，并对各种涡的流动机理进行了分析．结果表明：对称面的正、反向旋转涡、垂直截面的马蹄形涡的两翼周期性地交替脱落... 详细信息

对锥形角γ=30°扇形喷孔横向紊动射流进行了大涡模拟，在吹风比M=1．0工况下模拟了不同截面上涡量随时间变化的过程，并对各种涡的流动机理进行了分析．结果表明：对称面的正、反向旋转涡、垂直截面的马蹄形涡的两翼周期性地交替脱落成新的涡，对称面涡的周期为0．024S，马蹄形涡的周期为0．032S；反向旋涡对气膜冷却流场有重要影响，沿主气流流动方向的无量纲长度X／D在1～2时，反向旋涡的涡量值逐渐衰减；当X／D〉4时，反向旋涡开始逐渐消失，导致壁面附近的能量交换快，对底面的冷却效果好；由于在射流上游和下游的压力梯度不等，造成射流两侧的脉动速度变化不一致，导致了反向旋涡的不对称分布．

关键词：能源与动力工程燃气轮机叶片气膜冷却大涡模拟流场

Constructing core@shell structured photothermal nanosphere with thin carbon layer confined Co-Mn bimetals for pollutant degradation and solar interfacial water evaporation

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Rare Metals 2024年第4期43卷 1686-1701页

作者： Hong-Yang Zhu Meng-ting Liu Gang Wang Rong-Rong Du Hong-Yao Zhao Hao Lu Shi-Qi Yang Sheng Tang Zeng-Jing guo Jun Yang Cheng-Zhang Zhu Fu Yang School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang212003China School of Chemistry and Chemical Engineering Liaocheng UniversityLiaocheng252000China School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212003China School of Environmental Science and Engineering Nanjing Tech UniversityNanjing210009China

Photothermal material applied in environmental governance has attracted growing *** combining the Stober method and dopamine-triggered coating strategy,Co-Mn precursor was in situ incorporated into the poly dopamine(PDA)layer over the surface of silica ***,a unique photothermal nanosphere with SiO_(2)core and thin carbon layer and dual Co-Mn oxides shell was allowed to form by sequential heat treatment in the inert atmosphere(SiO_(2)@CoMn/C).The bimetallic fraction of Co/Mn in the carbon layer and post-treatment calcination temperature was comprehensively tuned to optimize the peroxymonosulfate(PMS)activation performance of the *** state of bimetallic species was studied including their physical distribution,chemical valence,and interplay by various ***,Co oxides appear as dominant monodispersed nanoparticles(~10 nm),while Mn with cluster-like morphology is observed to uniformly distribute over thin-layer carbon and adhered to the surface of SiO_(2)nanospheres(~250 nm).The calcined temperature could tune the oxidized state of Co species,leading to the optimization of the catalytic performance of introduced dual metal *** a result,this obtained optimal catalyst integrated the advantages of exposed bimetallic CoMn species and N-doped thin carbon to deliver excellent catalytic PMS activation performance and photothermal synergetic catalytic mineralization ability for diversiform *** reactions condition controls and anion interference studies were conducted to identify the adaptability of the optimal ***,the application of solar-driven interfacial water evaporation using optimal SiO_(2)@Co_3Mn_1/C-600 catalyst was explored,showing a high water evaporation rate of 1.48 kg·m^(-2)·h^(-1)and an efficiency of 95.2%,further revealing a comprehensive governance functionality of obtained material in the complex pollution condition.

关键词： Photothermal Peroxymonosulfate(PMS)activation Bimetallic synergy Water evaporation Advanced oxidation process

醋酸曲普瑞林联合膳食干预对特发性中枢性性早熟女童代谢及卵巢功能的影响

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中国现代医学杂志 2023年第11期33卷 81-86页

作者：杨婷梁希郭婷婷何雪张功安徽省儿童医院儿童保健科安徽合肥230001

目的探讨醋酸曲普瑞林联合膳食干预对特发性中枢性性早熟女童代谢及卵巢功能的影响。方法前瞻性选取2018年1月—2022年1月安徽省儿童医院100例特发性中枢性性早熟女童,采用随机数字表法分为对照组和研究组,每组50例。对照组采用膳食干预... 详细信息

目的探讨醋酸曲普瑞林联合膳食干预对特发性中枢性性早熟女童代谢及卵巢功能的影响。方法前瞻性选取2018年1月—2022年1月安徽省儿童医院100例特发性中枢性性早熟女童,采用随机数字表法分为对照组和研究组,每组50例。对照组采用膳食干预,研究组在对照组基础上联合醋酸曲普瑞林治疗,治疗周期均持续6个月。观察两组的临床疗效,比较两组治疗前、治疗6个月时的生长发育指标(身高、体重、预测成年终身高、体质量指数、骨龄)、代谢指标[骨密度值、维生素D、N端骨钙素(N-MID)、I型胶原羧基端肽β特殊序列(β-CTx)、Ⅰ型前胶原氨基端延长肽(PⅠNP)]、卵巢功能[孕酮(P)、睾酮(T)、雌二醇(E_(2))、催乳素(PRL)、促黄体生成素(LH)、促卵泡生成激素(FSH)],并统计两组不良反应发生情况。结果两组治疗前、治疗6个月各生长发育指标差值比较,差异有统计学意义(P<0.05),与对照组相比,研究组身高、预测成年终身高更高,体重更轻,骨龄更小;两组治疗前、治疗6个月各代谢指标差值比较,差异有统计学意义(P<0.05),两组骨密度值、维生素D水平高于治疗前,N-MID、β-CTx、PⅠNP水平低于治疗前,且研究组治疗前后各指标差值大于对照组;两组治疗前、治疗6个月各卵巢功能指标差值比较,差异有统计学意义(P<0.05),两组P、T、E_(2)、PRL、LH、FSH水平低于治疗前,且研究组治疗前后各指标差值大于对照组。治疗期间,两组均未发生明显不良反应。结论醋酸曲普瑞林联合膳食干预对特发性中枢性性早熟女童具有良好的治疗效果,能够改善患儿的生长发育状况,降低代谢水平,提升卵巢功能,且无明显不良反应。

关键词：特发性中枢性性早熟醋酸曲普瑞林膳食干预代谢卵巢功能

Dynamic Sulfur-Rich Polymers from Elemental Sulfur and Epoxides

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Chinese Journal of Polymer Science 2024年第10期42卷 1479-1487,I0010页

作者： Ke-Xiang Chen Chen-Hui Cui Zhen Li ting Xu Hao-Qing Teng Zhi-Yuan He Yin-Zhou guo Xiao-Qing Ming Zhi-Shen Ge Yan-Feng Zhang Tie-Jun Wang School of Chemistry Engineering Research Center of Energy Storage Materials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an710049China State Key Lab for Strength and Vibration of Mechanical Structures Department of Engineering MechanicsXi’an Jiaotong UniversityXi’an710049China

Sulfur-containing dynamic polymers had attracted significant attention due to their unique chemical structures with high *** sulfur, an inexpensive industrial waste product, to synthesize dynamic polysulfide polymers through reverse vulcanization has been a notable approach. However, this method required high temperatures and resulted in the release of unpleasant oders. In this study, we presented a robust method for the preparation of sulfur-rich polymers with dynamic polysulfide bonds from elemental sulfur and inexpensive epoxide monomers via a one-pot strategy at the mild room temperature. Different types of polysulfide molecules and polymers were synthesized by reacting various epoxide compounds with sulfur, along with the investigation of their structures and dynamic behaviors. It was noteworthy that the obatined polymers prepared from m-(2,3-epoxypropoxy)-N,N-bis(2,3-epoxypropyl)aniline and elemental sulfur exhibit multiple dynamic behaviors, including polysulfide metathesis and polysulfide-thiol exchange, enabling their rapid stress relaxation, self-healing, reprocessing and degradable properties of the cross-linked polymer. More importantly, the hydroxyl groups at the side chains from epoxide ring opening exhibited potential transesterification. This work provided a facile strategy for designing dynamic sulfur-rich polymers via a mild synthesis route.

关键词： Elemental sulfur Sulfur-containing polymer Dynamic covalent bond Dynamic polymer

昆虫细胞色素P450基因的多样性、进化及表达调控

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昆虫学报 2009年第3期52卷 301-311页

作者：郭亭亭姜辉高希武中国农业大学农学昆虫学系北京100193 农业部农药检定所北京100024

细胞色素P450单加氧酶(cytochrome P450 monooxygenases,P450s)是由多个功能相关的亚铁血红素-硫醇盐蛋白基因组成的一个基因超家族,在各种内源和外源物质的代谢中起着主要作用。目前GenBank中注册的昆虫P450基因序列已超过1000个,其中... 详细信息

细胞色素P450单加氧酶(cytochrome P450 monooxygenases,P450s)是由多个功能相关的亚铁血红素-硫醇盐蛋白基因组成的一个基因超家族,在各种内源和外源物质的代谢中起着主要作用。目前GenBank中注册的昆虫P450基因序列已超过1000个,其中双翅目占序列总数的74%,鳞翅目占序列总数的16%。而昆虫P450基因序列已克隆的全长序列中大部分属于CYP4和CYP6家族,两个家族成员分别占总数的20%和45%。利用GenBank中现已注册的昆虫P450基因的cDNA全长序列进行比对并绘制进化树,揭示不同种类昆虫P450的亲缘关系。结果显示基于P450基因的昆虫部分目的进化关系与大部分先前依据其他分子数据或形态分类学得到的昆虫系统进化关系基本吻合。现有研究表明,细胞色素P450基因的表达可能受顺式作用元件(cis-acting element)、反式作用因子(trans-acting factor)或两者共同调控,调控可能涉及转录增强的转录机制或mRNA稳定性增加的转录后机制。

关键词：细胞色素P450 多样性亲缘关系基因表达与调控