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The impact of typhoons on the biogeochemistry of dissolved organic matter in eutrophic bays in northwestern South China Sea

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Acta Oceanologica Sinica 2024年第6期43卷 15-31页

作者： xuan lu Qibin Lao Fajin Chen Guangzhe Jin Chunqing Chen Qingmei Zhu College of Ocean and Meteorology Guangdong Ocean UniversityZhanjiang 524088China Polar and Marine Research Institute College of Harbor and Coastal EngineeringJimei UniversityXiamen 361021China Key Laboratory for Coastal Ocean Variation and Disaster Prediction Guangdong Ocean UniversityZhanjiang 524088China Key Laboratory of Climate Resources and Environment in Continental Shelf Sea and Deep SeaDepartment of Education of Guangdong ProvinceGuangdong Ocean UniversityZhanjiang 524088China

Highly productive estuaries facilitate intense decomposition of dissolved organic matter(DOM) as a carbon ***,the specific impacts of typhoons on DOM decomposition in eutrophic bays remain *** address this issue,we investigated the spectral characteristics of DOM before and after Typhoon Ewiniar in Zhanjiang B ay,a eutrophic semi-enclosed bay in the northwestern South China *** results revealed that intense microbial decomposition of DOM occurred during the pre-typhoon period because high nutrient inputs facilitated the mobilization of DOM in the ***,the intrusion of external seawater induced by the typhoon diluted the nutrient levels in Zhanjiang B ay,reducing the impact of microbial decomposition on DOM during the post-typhoon perio ***,the net addition of DOM occurred in Zhanjiang Bay during the post-typhoon period,possibly because of the decomposition of particulate organic matter(POM) and desorption of particulate *** addition,an increase in apparent oxygen utilization,a decrease in DO saturation and the reduced level of Chl a indicated that organic matter(OM) decomposition was enhanced and OM decomposition shifted to POM decomposition in Zhanjiang Bay after the ***,our study highlighted the shift in the intense OM decomposition from DOM to POM decomposition before and after typhoons in eutrophic bays,providing new insights into the response of typhoons to biogeo chemistry.

关键词： dissolved organic matter optical analyses decomposition typhoon northwestern South China Sea

It?-Taylor Expansion Method of European Spread Option Pricing for Multivariate Diffusions with Jumps

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Acta Mathematicae Applicatae Sinica 2024年

作者： Ge WANG Yu-xuan lu Qing ZHOU Wei-lin XIAO School of Science Beijing University of Posts and Telecommunications Key Laboratory of Mathematics and Information Networks Beijing University of Posts and Telecommunications Ministry of Education Department of Mathematics National University of Singapore School of Management Zhejiang University

In this paper, we propose a new method for spread option pricing under the multivariate irreducible diffusions without jumps and with different types of jumps by the expansion of the transition density function. By the quasi-Lamperti transform, which unitizes the diffusion matrix at the initial time, and applying the small-time It?-Taylor expansion method, we derive explicit recursive formulas for the expansion coefficients of transition densities and spread option prices for multivariate diffusions with jumps in return. It is worth mentioning that we also give the closed-form formula of spread option price whose underlying asset price processes contain a Merton jump and a double exponential jump, which is innovative compared with current literature. The theoretical proof of convergence is presented in detail.

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Distribution and sources of sedimentary organic matter in different aquaculture areas of northeastern Zhanjiang Bay using stable carbon and nitrogen isotopes

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Acta Oceanologica Sinica 2024年第6期43卷 38-48页

作者： Fengxia Zhou Shuangling Wang Han Fang Jiani He Liang Ye Zhaohai Ding Cuiting Li Fajin Chen xuan lu Chunqing Chen Yafei Meng College of Ocean and Meteorology Guangdong Ocean UniversityZhanjiang 524088China Key Laboratory for Coastal Ocean Variation and Disaster Prediction Guangdong Ocean UniversityZhanjiang 524088China Key Laboratory of Climate Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong ProvinceGuangdong Ocean UniversityZhanjiang 524088China

Zhanjiang Bay is a major aquaculture area in China with many types of mariculture products(such as oysters,fish,and shrimp).The culture area and shrimp output in Zhanjiang Bay are ranked first in *** investigated the total organic carbon(TOC),total nitrogen(TN),TOC/TN ratio,and stable isotopes(δ^(13)C and δ^(15)N) of the fish and shrimp feed,fish and shrimp feces,and sedimentary organic matter(SOM) in and around different aquaculture areas of northeastern Zhanjiang B ay to study the impact of aquaculture activities on *** average TOC contents of fish and shrimp feed were 39.20%±0.91% and 39.29%±0.21%,*** average TOC content in the surface sediments of the oyster culture area,the mixed(fish and shrimp) culture area,and the cage fish farm area were 0.66%,0.88%±0.10%,and 0.58%±0.19%,respectively,which may indicate that mixed culture had a greater impact on *** relatively high TOC and TN contents and relatively low TOC/TN ratios,and δ^(15)N values in the upper layer of the core sediment in the mixed culture area could also support the significant influence of mixed *** average δ^(13)C and δ^(15)N values of fish and shrimp feed were -20.6‰±2.2‰ and 1.8‰±1.2‰,respectively,which were different from the isotopic values of SOM in the study area.δ^(13)C and δ^(15)N values for SOM in different aquaculture areas were different from those of nearby reference stations,probably reflecting the influence of *** δ^(13)C and δ^(15)N values in the oyster culture area(-25.9‰ and6.0‰,respectively) seemed to have reduced δ^(13)C and enriched δ^(15)N relative to those of the reference station(-24.6‰ and 5.8‰,respectively).This may reflect the influence of organic matter on oyster *** δ^(15)N value of the station in the mixed culture area(7.1‰±0.4‰) seemed to be relatively enriched in δ^(15)N relative to that of the reference station(6.6‰).Sedimentation and the subsequent degradation of organic matter from mixed cultures may have contrib

关键词： sedimentary organic matter aquaculture stable isotopes sources Zhanjiang Bay

Metabolites isolated from Penicillium HDS-Z-1E, an endophytic fungal strain isolated from Taxus cuspidata and their activation effect of catalase

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Chinese Herbal Medicines 2024年第2期16卷 227-230页

作者： Chuan Tang Rui Gao Xiaoyuan Tang Yu Zhang Weixing Feng Baomin Feng xuan lu College of Life and Health Dalian UniversityDalian 116622China

Objective:To study the compounds isolated from Penicillium HDS-Z-1E,an endophytic fungal strain isolated from Taxus cuspidata and their activation effect of catalase(CAT).Methods:The chemical constituents were isolated from Penicillium HDS-Z-1E,by using silica gel,Sephadex LH-20 and *** structural elucidations of five metabolites were elucidated on the basis of spectroscopic including 1 H-NMR,13C-NMR,HMBC and *** activation sites of catalase have been investigated by molecular ***:Five metabolites,compounds(1–5)were isolated from Penicillium HDS-Z-1E and identified as 4-hydroxy-4-methyltetrahydro-2H-pyran-2-one(1),4-hydroxymethyl-5,6-dihydro-pyran-2-one(2),5,6-dihydro-2-oxo-2H-pyran-4-carboxylic(3),N-acetyl-hydrazinobenzoic acid(4),and methyl 2-(2,5-dihydroxyphenyl)acetate(5).Conclusion:Compound 3 is a new *** 3 and 4 may have potential activators of catalase,providing a theoretical basis for the development of CAT activators.

关键词： catalase activators 5,6-dihydro-2-oxo-2H-pyran-4-carboxylic molecular simulation penicillium Taxus cuspidata Sieb.et Zucc

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利用化工废水电解制氢电极及电解槽系统

分子催化（中英文） 2024年第2期38卷 197-197,I0006页

作者：吕功煊中国科学院兰州化学物理研究所羰基合成与选择氧化国家重点实验室甘肃兰州730000

中国科学院兰州化学物理研究所研究团队发展出以复合过渡金属为主要组成的复合电极作为AEM电解槽的阳极,镍基复合电极作为阴极的电极系统,可连续运行100 d,产氢的电效率可达到60%,该技术攻克了电解槽膜堵塞的难题,实现了化工废水的资源... 详细信息

中国科学院兰州化学物理研究所研究团队发展出以复合过渡金属为主要组成的复合电极作为AEM电解槽的阳极,镍基复合电极作为阴极的电极系统,可连续运行100 d,产氢的电效率可达到60%,该技术攻克了电解槽膜堵塞的难题,实现了化工废水的资源化利用转化为绿氢.

关键词：电解制氢过渡金属复合电催化剂化工废水

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改进鲸鱼优化算法的壁面红外反射特性求解

中国光学（中英文） 2024年第3期17卷 595-604页

作者：张潞樊金浩鲁宇轩张磊傅莉沈阳航空航天大学辽宁沈阳110136 沈阳飞机设计研究所辽宁沈阳110136

壁面的红外反射特性由双向反射分布函数(BRDF)表征和求解。目前BRDF测量需要大量实验数据,同时存在精度不高的问题。通过构建壁面反射特性测试平台,使用MR170型傅立叶红外光谱辐射计获取2~15μm波段下入射角度和各个反射角度的目标辐射... 详细信息

壁面的红外反射特性由双向反射分布函数(BRDF)表征和求解。目前BRDF测量需要大量实验数据,同时存在精度不高的问题。通过构建壁面反射特性测试平台,使用MR170型傅立叶红外光谱辐射计获取2~15μm波段下入射角度和各个反射角度的目标辐射亮度。针对隐身目标,应用RBF网络对3~5μm以及8~14μm波段的辐射亮度曲线进行拟合,排除大气干扰,进而求解出上述两个波段隐身目标的BRDF值。为了解决BRDF模型精度不高的问题,提出了改进的鲸鱼优化算法(IWOA),对BRDF模型参数进行反演,并设计了基于BRDF的反射率求解方法。IWOA对BRDF计算模型参数反演有良好的效果。根据反射法,应用所得到的BRDF数据求解得到的反射率为0.5496,相对误差为6.17%,满足工程需求。

关键词：双向反射分布函数(BRDF) 鲸鱼优化算法辐射亮度参数反演

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祸兮福兮?监管处罚对保险公司业绩表现的影响——基于分支机构视角

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保险研究 2024年第1期 72-88页

作者：卢雨萱赵桂芹上海财经大学金融学院

本文基于手工整理的保险公司分支机构的行政处罚数据,研究了监管处罚对财产保险公司的业绩表现是否以及如何产生影响。研究表明,监管处罚发挥了直接威慑效应,抑制了违规分支机构的业绩增长,且这种威慑效应是短期的。此外,监管处罚还发... 详细信息

本文基于手工整理的保险公司分支机构的行政处罚数据,研究了监管处罚对财产保险公司的业绩表现是否以及如何产生影响。研究表明,监管处罚发挥了直接威慑效应,抑制了违规分支机构的业绩增长,且这种威慑效应是短期的。此外,监管处罚还发挥了间接威慑作用,降低了与违规分支机构同属一家公司的其他分支机构的业绩表现,但对同一地区下其他公司的分支机构无显著影响。区分公司业务类型、股权性质、监管处罚类型和公司所处地区后发现,监管处罚的直接威慑效应存在异质性。进一步地,佣金激励、营销员规模和信任水平会弱化监管处罚对业绩表现的抑制作用。本研究验证了行政处罚的有效性,为监管机构健全和完善保险监管制度、深化属地监管改革提供了经验证据。

关键词：监管处罚业绩表现威慑效应

表现为苔藓样损害的拟诊IgG4-RD 1例

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口腔医学研究 2024年第6期40卷 561-563页

作者：张天玉陆轩江潞口颌系统重建与再生全国重点实验室国家口腔疾病临床医学研究中心、陕西省口腔疾病临床医学研究中心、空军军医大学第三附属医院儿童口腔科陕西西安710032 大连市口腔医院修复科辽宁大连116021 口腔疾病研究国家重点实验室、国家口腔疾病临床医学研究中心、四川大学华西口腔医院黏膜病科四川成都610041

免疫球蛋白G4相关疾病(immunoglobulin G4-related disease,IgG4-RD)是一种全身性多器官纤维炎性疾病,罕见累及口腔黏膜的病例报道。本文报道1例临床表现为苔藓样损害的拟诊IgG4-RD的诊治,该报道丰富了IgG4-RD口腔黏膜病损表现,同时提... 详细信息

免疫球蛋白G4相关疾病(immunoglobulin G4-related disease,IgG4-RD)是一种全身性多器官纤维炎性疾病,罕见累及口腔黏膜的病例报道。本文报道1例临床表现为苔藓样损害的拟诊IgG4-RD的诊治,该报道丰富了IgG4-RD口腔黏膜病损表现,同时提示临床实践中鉴别诊断的重要性。

关键词：免疫球蛋白G4相关性疾病自身免疫性疾病苔藓样损害

基于IGA-BP神经网络的智能电能计量设备状态自动检测系统

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计算机测量与控制 2024年第8期32卷 138-144页

作者：卢旋广西壮族自治区计量检测研究院南宁530299

针对不断扩大的电网规模和愈加复杂的外部环境对智能电能计量设备安全稳定运行带来的挑战,研究了基于IGA-BP神经网络的智能电能计量设备状态自动检测系统的设计;系统硬件包括数据采集模块、信号处理模块、数据传输模块和数据分析模块;... 详细信息

针对不断扩大的电网规模和愈加复杂的外部环境对智能电能计量设备安全稳定运行带来的挑战,研究了基于IGA-BP神经网络的智能电能计量设备状态自动检测系统的设计;系统硬件包括数据采集模块、信号处理模块、数据传输模块和数据分析模块;在软件方面,系统采集智能电能计量设备的检测数据,选取基础电能计量误差、电压波动幅度、电流波动幅度、功率因数作为智能电能计量设备状态量;引入IGA-BP神经网络对状态量进行迭代运算,实现了智能电能计量设备状态的自动检测;实验结果表明,该系统对智能电能计量设备状态检测的最短时间为2 s,检测结果与实际结果一致,验证了系统具有较高的设备状态检测效率和精度。

关键词：检测系统智能电能计量设备传感器 IGA-BP神经网络模型状态检测

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