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Abundance and sources of particulate polycyclic aromatic hydrocarbons and aromatic acids at an urban site in central China

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Journal of Environmental Sciences 2024年第8期142卷 155-168页

作者： Luqi Shang Zhe Dong zihan Li Mingkai Wang zihan kong Xiao Li Ruiqin Zhang School of Ecology and Environment Zhengzhou UniversityZhengzhou 450001China College of Chemistry Zhengzhou UniversityZhengzhou 450001China Institute of Environmental Sciences Zhengzhou UniversityZhengzhou 450001China

We conducted a simultaneous field study of PM_(2.5)-bound particulate polycyclic aromatic hydrocarbons(PAHs)and aromatic acids(AAs)in a polluted city Zhengzhou to explore the concentration,sources and potential conversion pathways between PAHs and AAs in different *** average concentrations of PM_(2.5),28PAHs and 8AAs during the sampling period were 77μg/m^(3),75 ng/m^(3),and 283 ng/m^(3),*** concentration of both28PAHs and 8AAs were highest in winter and lowest in summer with ratios of 6.3 and 2.3,*** with 5-7 rings were the main components of PAHs(52%),followed by 4rings PAHs(30%)and 2-3 rings PAHs(18%).According to the source appointment results obtained by positive matrix factorization,the main sources of PAHs were combustion and vehicle emissions,which account for 37%and 34%,respectively.8AAs were divided into three groups,including four benzene dicarboxylic acids(B2CAs),three benzene tricarboxylic acids(B3CAs)and one benzene tetracarboxylic acid(B4CA).And interspecies correlation analysis with PM_(2.5)source markers were used to investigate potential *** acid(o-Ph)was the most abundant specie of 8AAs(157 ng/m^(3),55%of 8AAs),which was well correlated with ***,B3CAs and B4CA were highly correlated with sulfate and weakly correlated with levoglucosan,suggesting that secondary formation was their main *** logical oxidation products of PAHs,o-Ph and B3CAs showed good correlations with a number of PAHs,indicating possible photochemical oxidation pathway by *** addition,O_(3),NO_(2),temperature and relative humidity have positive effects on the secondary formation of B3CAs.

关键词： Polycyclic aromatic hydrocarbons Aromatic acids Source appointment Secondary formation

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混合式配电变压器功角优化控制

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西安交通大学学报 2024年第7期58卷 116-128页

作者：柳轶彬栗世超梁得亮孔子涵薛彦廷西安交通大学电工材料电气绝缘全国重点实验室西安710049 陕西省智能电网重点实验室西安710049

针对现有同相位控制无法使混合式配电变压器(HDT)损耗达到最小的问题,提出了HDT的最小损耗模式,以实现功角优化控制,从而降低其运行损耗。首先,建立HDT的相量关系,导出可变损耗与负荷、功率因数角、网侧电压波动系数、功角之间的函数关... 详细信息

针对现有同相位控制无法使混合式配电变压器(HDT)损耗达到最小的问题,提出了HDT的最小损耗模式,以实现功角优化控制,从而降低其运行损耗。首先,建立HDT的相量关系,导出可变损耗与负荷、功率因数角、网侧电压波动系数、功角之间的函数关系;然后,导出最优功角的解析公式,据此建立最小损耗模式的计算流程,从而提出HDT功角优化控制策略。该策略的突出特点在于实时检测电网及负荷工况,进而在线算出实现最小损耗的最优功角;理论分析指出,负荷越轻、越接近纯阻性,电压同相位模式更接近最小损耗模式;反之,电流同相位模式更接近最小损耗模式。仿真及实验结果表明:在网侧电压波动及负载电流畸变工况下,所提出的功角优化控制策略能在实现网侧电流正弦单位功率因数控制及负载电压正弦稳定控制的前提下,有效减小HDT的损耗;轻载工况下,相比电流同相位模式,仿真和实验最小损耗模式能减小可变损耗的60%和42%;在额定负载下,相比电压同相位模式,仿真和实验最小损耗模式能减小可变损耗的46%和37%。

关键词：混合式配电变压器相量关系功角优化最小损耗

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Improving constraint onΩ_(m)from SDSS using marked correlation functions

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 207-224页

作者： Limin Lai Jiacheng Ding Xiaolin Luo Yizhao Yang zihan Wang Keshi Liu Guanfu Liu Xin Wang Yi Zheng Zhaoyu Li Le Zhang Xiao-Dong Li School of Physics and Astronomy Sun Yat-sen University Zhuhai CampusZhuhai 519082China Department of Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Department of Astronomy Tsinghua UniversityBeijing 100084China CSST Science Center for the Guangdong-Hong kong-Macao Greater Bay Area SYSUZhuhai 519082China Peng Cheng Laboratory Shenzhen 518000China

Large-scale structure(LSS)surveys will increasingly provide stringent constraints on our cosmological ***,the density-marked correlation function(MCF)has been introduced,offering an easily computable density-correlation *** have demonstrated that MCFs offer additional,independent constraints on cosmological models beyond the standard two-point correlation(2PCF).In this study,we apply MCFs for the first time to SDSS CMASS data,aiming to investigate the statistical information regarding clustering and anisotropy properties in the Universe and assess the performance of various weighting schemes in MCFs,and finally obtain constraints onΩ_(m).Upon analyzing the CMASS data,we observe that,by combining different weights(α=[-0.2,0,0.2,0.6]),the MCFs provide a tight and independent constraint on the cosmological parameterΩ_(m),yieldingΩ_(m)=0.293±0.006 at the 1σlevel,which represents a significant reduction in the statistical error by a factor of 3.4 compared to that from *** constraint is consistent with recent findings from the small-scale clustering of BOSS galaxies(Zhai et ***.J.948,99(2023))within the 1σ***,we also find that our estimate is lower than the Planck measurements by about 2.6σ,indicating the potential presence of new physics beyond the standard cosmological model if all the systematics are fully *** method outlined in this study can be extended to other surveys and datasets,allowing for the constraint of other cosmological ***,it serves as a valuable tool for forthcoming emulator analysis on the Chinese Space Station Telescope(CSST).

关键词： large scale structure of universe dark energy cosmological parameters marked weighted correlation function

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基于主成分分析和节点像差理论的公差降敏方法

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红外与激光工程 2024年第2期53卷 187-196页

作者：官子涵王敏李晓彤浙江大学光电科学与工程学院浙江杭州310027 浙江大学极端光学技术与仪器全国重点实验室浙江杭州310027 先进科技(香港)有限公司中国香港特别行政区999077

为了在设计阶段预测光学系统加工装配后的像质并降低加工装配难度,提升设计效率,文中提供了一个高效的公差灵敏度降低方法。首先使用Zernike多项式量化像差,基于线性代数理论和Monte Carlo分析寻找引入扰动后系统的像差变化规律,通过降... 详细信息

为了在设计阶段预测光学系统加工装配后的像质并降低加工装配难度,提升设计效率,文中提供了一个高效的公差灵敏度降低方法。首先使用Zernike多项式量化像差,基于线性代数理论和Monte Carlo分析寻找引入扰动后系统的像差变化规律,通过降维后的像差场以及特征值分布确定主要引入像差;对系统制造过程中可能出现的失对称扰动和轴向扰动进行建模,基于节点像差理论描述扰动造成的引入像差,并通过统计分析确定关键表面;根据Zernike项与波像差的对应关系对像差空间进行变换,提出相应的评价函数纳入优化,进而抑制新像差的产生。将这一方法应用于两个不同的光学系统的设计,优化后预期加工性能(指定空间频率处98%置信度的MTF表现)分别提升了约68%和20%。与使用Zemax软件中TOLR操作数优化相比,结构1的优化时间由7 h缩短到36 min,并且在结构2的优化中成功实现了公差降敏。结果表明,该方法能够在提升效率的同时有效降低公差灵敏度。

关键词：光学设计公差降敏主成分分析节点像差理论

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Improving constraint on Ωfrom SDSS using marked correlation functions

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Science China(Physics,Mechanics & Astronomy) 2024年

作者： Limin Lai Jiacheng Ding Xiaolin Luo Yizhao Yang zihan Wang Keshi Liu Guanfu Liu Xin Wang Yi Zheng Zhaoyu Li Le Zhang Xiaodong Li School of Physics and Astronomy Sun Yat-sen University Zhuhai Campus Department of Astronomy Shanghai Jiao Tong University Department of Astronomy Tsinghua University CSST Science Center for the Guangdong-Hong kong-Macao Greater Bay Area SYSU Peng Cheng Laboratory

Large-scale structure （LSS） surveys will increasingly provide stringent constraints on our cosmological ***,the density-marked correlation function （MCF） has been introduced,offering an easily computable density-correlation *** have demonstrated that MCFs offer additional,independent constraints on cosmological models beyond the standard two-point correlation （2PCF）.In this study,we apply MCFs for the first time to SDSS CMASS data,aiming to investigate the statistical information regarding clustering and anisotropy properties in the Universe and assess the performance of various weighting schemes in MCFs,and finally obtain constraints on Ω*** analyzing the CMASS data,we observe that,by combining different weights （α=[-0.2,0,0.2,0.6]）,the MCFs provide a tight and independent constraint on the cosmological parameter Ωm,yielding Ωm=0.293±0.006 at the 1σlevel,which represents a significant reduction in the statistical error by a factor of 3.4compared to that from *** constraint is consistent with recent findings from the small-scale clustering of BOSS galaxies(Zhai et ***.J.948,99 （2023）) within the 1σ***,we also find that our estimate is lower than the Planck measurements by about 2.6σ,indicating the potential presence of new physics beyond the standard cosmological model if all the systematics are fully *** method outlined in this study can be extended to other surveys and datasets,allowing for the constraint of other cosmological ***,it serves as a valuable tool for forthcoming emulator analysis on the Chinese Space Station Telescope （CSST）.

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江苏省乡村地域功能分异特征及其多功能性研究

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科技和产业 2022年第4期22卷 229-234页

作者：孔子涵李娴张佳慧徐紫月杨蔚南京财经大学公共管理学院南京210046

以江苏省为例,从经济发展、农业生产、社会保障、生态保育4个角度构建乡村地域功能评价体系,基于GIS空间分析方法,揭示江苏省乡村地域功能空间分异特征,并进一步探究各功能间的权衡关系以及江苏省乡村地域多功能性空间分布状况。研究结... 详细信息

以江苏省为例,从经济发展、农业生产、社会保障、生态保育4个角度构建乡村地域功能评价体系,基于GIS空间分析方法,揭示江苏省乡村地域功能空间分异特征,并进一步探究各功能间的权衡关系以及江苏省乡村地域多功能性空间分布状况。研究结果显示:江苏省乡村地域功能空间分异特征明显,经济发展功能呈现南高北低的分布特征,农业生产热点区主要位于苏北,生态保育功能呈现南北高、中部低的分布特征,社会保障功能强的区域为南京、苏州及周边地区;经济发展、农业生产、生态保育、社会保障4项功能间存在权衡关系,经济发展功能与其余功能权衡强度最大,社会保障功能与其余功能权衡强度最小;江苏省乡村地域多功能区主要分布在苏南,乡村地域单功能区主要分布于苏中和苏北部分沿海地区,乡村地域非多功能区主要位于苏北西部地区及泰州市部分地区。

关键词：江苏省乡村地域功能分异特征多功能性功能分区

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东北自然发酵酸菜细菌多样性及其与生物胺的关系

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食品科学技术学报 2024年第2期42卷 131-141页

作者：隋雨萌王家旺马子涵王慧平孔保华刘鑫任皓威陈倩东北农业大学食品学院黑龙江哈尔滨150030

酸菜是我国东北地区独具特色的传统发酵食品。酸菜发酵过程中复杂的微生物代谢过程会产生潜在的危害物——生物胺。以东北不同地区自然发酵酸菜为对象,研究酸菜细菌多样性及其与生物胺的关系。研究表明,6个地区的酸菜样品总酸、亚硝酸... 详细信息

酸菜是我国东北地区独具特色的传统发酵食品。酸菜发酵过程中复杂的微生物代谢过程会产生潜在的危害物——生物胺。以东北不同地区自然发酵酸菜为对象,研究酸菜细菌多样性及其与生物胺的关系。研究表明,6个地区的酸菜样品总酸、亚硝酸盐、食盐、还原糖、游离氨基酸、生物胺含量,菌落总数及乳酸菌总数存在显著差异,其中菌落总数、乳酸菌总数及生物胺含量分别为5.11~5.81 lg(CFU/g)、4.09~5.12 lg(CFU/g)、59.22~131.34 mg/kg。采用高通量测序分析技术对东北自然发酵酸菜样品中细菌群落结构组成进行对比分析。结果表明,酸菜样品中的优势细菌属主要包括乳杆菌属和节杆菌属。Spearman相关性分析表明,在相对丰度排名前10位的细菌属中,不溶螺杆菌属与尸胺含量呈显著正相关(P<0.05),与组胺含量呈极显著负相关(P<0.01);弓形杆菌属与精胺含量呈显著负相关(P<0.05);丛毛单胞菌属与亚精胺含量呈显著正相关(P<0.05);小球菌属与酪胺含量呈极显著正相关(P<0.01);不溶螺杆菌属和节杆菌属与酪胺含量呈显著负相关(P<0.05);普雷沃氏菌属与精胺含量呈极显著负相关(P<0.01)。因此,在后续研究中可以通过分离纯化与生物胺呈负相关的菌株作为功能性发酵剂,抑制发酵蔬菜中生物胺的产生及积累。研究旨在为了解生物胺形成规律及机制,有效控制酸菜生物胺生成,提升自然发酵酸菜品质及安全性提供理论依据。

关键词：东北酸菜细菌多样性化学成分生物胺相关性分析

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Morphological evolution and flow conduction characteristics of fracture channels in fractured sandstone under cyclic loading and unloading

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International Journal of Mining Science and Technology 2023年第12期33卷 1527-1540页

作者： Quanle Zou zihan Chen Jinfei Zhan Chunmei Chen Shikang Gao Fanjie kong Xiaofeng Xia State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety EngineeringChongqing UniversityChongqing 400044China School of Mining Guizhou UniversityGuiyang 550025China

In coal mining,rock strata are fractured under cyclic loading and unloading to form fracture *** channels are the main flow narrows for ***,expounding the flow conductivity of fracture channels in rocks on fluids is significant for gas flow in rock *** this regard,graded incremental cyclic loading and unloading experiments were conducted on sandstones with different initial stress ***,the three-dimensional models for fracture channels in sandstones were ***,the fracture channel percentages were used to reflect the flow conductivity of fracture *** study revealed how the particle size distribution of fractured sandstone affects the formation and expansion of fracture *** was found that a smaller proportion of large blocks and a higher proportion of small blocks after sandstone fails contribute more to the formation of fracture *** proportion of fracture channels in fractured rock can indicate the flow conductivity of those *** the proportion of fracture channels varies gently,fluids flow evenly through those ***,if the proportion of fracture channels varies significantly,it can greatly affect the flow rate of *** research results contribute to revealing the morphological evolution and flow conductivity of fracture channels in sandstone and then provide a theoretical basis for clarifying the gas flow pattern in the rock strata of coal mines.

关键词： CT imaging Flow conductivity Three-dimensional reconstruction Proportion of fracture channels Cyclic loading and unloading

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数字化背景下高职化工专业转型升级策略

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化工管理 2024年第6期 42-46页

作者：王潇唐利平孔新海陈咨含广安职业技术学院四川广安638000

全球经济数字化持续激发经济社会发展的新动力,随着化工产业向智能化、高端化发展,对人才的需求也发生根本性的变化。如何系统构建适应产业发展需求的人才培养体系,实现高素质技术技能人才的培养目标,满足新时代企业的用人需求,已成为... 详细信息

全球经济数字化持续激发经济社会发展的新动力,随着化工产业向智能化、高端化发展,对人才的需求也发生根本性的变化。如何系统构建适应产业发展需求的人才培养体系,实现高素质技术技能人才的培养目标,满足新时代企业的用人需求,已成为高职院校教育改革的重点。文章针对高职化工专业在人才培养中面临的三个问题,从师资队伍、产教融合、课程体系及教学环节四个方面探讨了专业转型升级的策略,旨在为同类专业提供参考。

关键词：专业建设师资队伍产教融合

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Evaluation and intelligent deployment of coal and coalbed methane coupling coordinated exploitation based on Bayesian network and cuckoo search

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International Journal of Mining Science and Technology 2022年第6期32卷 1315-1328页

作者： Quanle Zou zihan Chen Zhiheng Cheng Yunpei Liang Wenjie Xu Peiran Wen Bichuan Zhang Han Liu Fanjie kong State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety EngineeringChongqing UniversityChongqing 400044China North China Institute of Science and Technology Beijing 100083China Key Laboratory of Mine Disaster Prevention and Control in Hebei Province Langfang 065000China

Coal and coalbed methane(CBM)coordinated exploitation is a key technology for the safe exploitation of both ***,existing studies lack the quantification and evaluation of the degree of coordination between coal mining and coalbed methane *** this study,the concept of coal and coalbed methane coupling coordinated exploitation was proposed,and the corresponding evaluation model was established using the Bayesian *** this basis,the objective function of coal and coalbed methane coordinated exploitation deployment was established,and the optimal deployment was determined through a cuckoo *** results show that clarifying the coupling coordinated level of coal and coalbed methane resource exploitation in coal mines is conducive to adjusting the deployment plan in *** case study results show that the evaluation and intelligent deployment method proposed in this paper can effectively evaluate the coupling coordinated level of coal and coalbed methane resource exploitation and intelligently optimize the deployment of coal mine *** optimization results demonstrate that the safe and efficient exploitation of coal and CBM resources is promoted,and coal mining and coalbed methane extraction processes show greater *** observations and findings of this study provide a critical reference for coal mine resource exploitation in the future.

关键词： Coal and coalbed methane Coupling coordinated exploitation Bayesian network Cuckoo search Intelligent optimization

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