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工程建设与设计 2024年第8期 231-233页

作者：周立丹沧州渤海新区黄骅市港城产业园区自然资源和规划建设分局河北沧州061113

研究了建筑市场监管信息化现状与优化策略,明确了建筑市场监管信息化基本组织架构,分析了信息化建设中存在的主要问题,并从规划设计与技术支持、数据横向传递效率、数据采集时效性、数据利用价值等方面出发,提出了建筑市场监管信息化的... 详细信息

研究了建筑市场监管信息化现状与优化策略,明确了建筑市场监管信息化基本组织架构,分析了信息化建设中存在的主要问题,并从规划设计与技术支持、数据横向传递效率、数据采集时效性、数据利用价值等方面出发,提出了建筑市场监管信息化的优化策略。

关键词：建筑市场监管信息化管理现状分析优化策略

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基于混合桥海上风电高压直流变换器研究

电力电子技术 2024年第2期58卷 101-104页

作者：姚钢刘晴周荔丹上海电力大学电气工程学院上海200090 上海交通大学电子信息与电气工程学院电气工程系上海200240

海上风机一直往大容量发展,模块化多电平变换器(MMC)安全稳定的运行和子模块数目的任意配置显得尤为重要。此处提出的双极性高压直流变换器,利用全桥子模块可输出负电压,正负电压相抵消原理,突破了上下桥臂子模块需成比例配置的局限性,... 详细信息

海上风机一直往大容量发展,模块化多电平变换器(MMC)安全稳定的运行和子模块数目的任意配置显得尤为重要。此处提出的双极性高压直流变换器,利用全桥子模块可输出负电压,正负电压相抵消原理,突破了上下桥臂子模块需成比例配置的局限性,同时实现了开关管的低电压变化率(du/dt)开通和关断。设计了适配的调制策略和稳压控制方案,实现桥臂子模块电压的稳定与均衡。最后,搭建、配置了样机实验平台,验证了所提理论及仿真分析的合理性。

关键词：模块化多电平变换器高压均衡

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弱电网下多逆变器并网系统全局谐振抑制

电力电子技术 2024年第3期58卷 97-100页

作者：姚钢杨晓帆周荔丹上海电力大学电气工程学院上海200090 上海交通大学电子信息与电气工程学院上海200240

弱电网条件下,各逆变器之间以及逆变器与电网之间会形成交互耦合,从而影响到系统的稳定运行。针对该问题,提出了一种弱电网下多逆变器并网系统的全局谐振抑制策略。首先,基于并网电流反馈,提出改进的有源阻尼策略形成虚拟阻抗,来增加逆... 详细信息

弱电网条件下,各逆变器之间以及逆变器与电网之间会形成交互耦合,从而影响到系统的稳定运行。针对该问题,提出了一种弱电网下多逆变器并网系统的全局谐振抑制策略。首先,基于并网电流反馈,提出改进的有源阻尼策略形成虚拟阻抗,来增加逆变器自身阻尼,从而抑制多逆变器并联谐振;其次,通过结合电网阻抗测量的改进电网电压前馈策略,抑制电网背景谐波电压通过电网阻抗产生的谐波谐振,从而提高多逆变器并网系统的稳定性。仿真和实验结果均验证了所提谐振抑制策略的有效性和可行性。

关键词：逆变器弱电网谐振抑制

Use of Helical Strakes for FIV Suppression of Two Inclined Flexible Cylinders in A Side-by-Side Arrangement

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China Ocean Engineering 2018年第3期32卷 331-340页

作者： XU Wan-hai ZHANG Shu-hai zhou li-dan GAO Xi-feng State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China Collaborative Innovation Centre for Advanced Ship and Deep-Sea Exploration Shanghai 200240China

The experimental studies on flow-induced vibrations(FIV) reduction of two side-by-side flexible cylinders inclined at 45° by using the helical strakes were carried out in a towing tank. The main aim of the experiment is to check whether the helical strakes with a pitch of 17.5 D and a height of 0.25 D, which is considered as the most effective vibration suppression device for the isolated cylinder undergoing vortex-shedding, still perform very well to reduce FIV of two inclined flexible cylinders in a side-by-side arrangement. The vibration of two identical inclined cylinders with a mass ratio of 1.90 and an aspect ratio of 350 was tested in the experiment. The center-to-center distance between the two cylinders was 3.0 D. The uniform flow was simulated by towing the cylinder models along the *** towing velocity varied from 0.05 to 1.0 m/s with an interval of 0.05 m/s. The maximum Reynolds number can be up to 1.6×104. Three cases were experimentally studied in this paper, including two side-by-side inclined smooth cylinders, only one smooth cylinder fitted with helical strakes in the two side-by-side inclined cylinders system and both two cylinders attached with helical strakes. The variations of displacement amplitude, dominant frequency, FIV suppression efficiency and dominant mode for the two side-by-side inclined cylinders with reduced velocity were shown and discussed.

关键词： helical strakes FIV suppression inclined cylinder side-by-side towing tank experiment

急性髓系白血病患儿化疗期间症状群发生情况及影响因素分析

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中国妇幼保健 2024年第14期39卷 2611-2614页

作者：蔡建萍周丹丽熊亚琴鲍群谢浙江大学医学院附属儿童医院血液科浙江杭州310000 绍兴文理学院医学院护理实验室

目的分析急性髓系白血病(AML)患儿化疗期间症状群发生情况及其影响因素。方法回顾性分析2020年1月1日—2022年12月31日浙江大学医学院附属儿童医院收治的66例AML患儿的一般资料。采用记忆症状评估量表儿童版(MSAS10-18)评估患儿症状群... 详细信息

目的分析急性髓系白血病(AML)患儿化疗期间症状群发生情况及其影响因素。方法回顾性分析2020年1月1日—2022年12月31日浙江大学医学院附属儿童医院收治的66例AML患儿的一般资料。采用记忆症状评估量表儿童版(MSAS10-18)评估患儿症状群发生情况,并根据患儿是否在化疗期间出现症状群,将66例AML患儿分为发生症状群组(47例)和未发生症状群组(19例)。比较两组患儿一般资料(性别、年龄、病程、住院时间、父母年龄、父母文化程度、家庭月收入及家庭关系等)。通过单因素和多因素logistic回归分析影响AML化疗期间发生症状群的因素,根据影响因素进行赋值用以建立风险评估模型,采用受试者工作特征(ROC)曲线评估模型诊断效能。结果66例患儿中,共有47例患儿在化疗期间出现症状群,其中神经心理不适症状群、头部相关症状群、胃肠道相关症状群、自我形象受损相关症状群、皮肤瘙痒-腹泻症状群、口腔相关症状群分别为3例、6例、11例、7例、14例及6例,依次占比6.38%、12.76%、23.40%、14.89%、29.78%及12.76%。发生症状群组年龄、病程、住院时间、父母年龄、父母文化程度、家庭月收入及家庭关系方面与未发生症状群组比较,差异均有统计学意义(均P<0.05)。多因素logistic回归模型分析结果显示,年龄(OR=5.783)、病程(OR=2.389)、父母年龄(OR=1.235)、父母文化程度(OR=32.460)、家庭月收入(OR=1.107)及家庭关系(OR=18.616)是患儿化疗期间发生症状群的独立影响因素(均P<0.05)。由ROC曲线分析,构建风险评估模型的AUC值最高,为0.968,且灵敏度、特异度分别为97.87%、89.36%。结论AML患儿在化疗期间症状群发生率较高,并以皮肤瘙痒-腹泻症状群、胃肠道相关症状群、自我形象受损相关症状群为主。AML患儿化疗期间发生症状群的独立影响因素包括患儿年龄、病程、父母年龄、父母文化程度、家庭月收入及家庭关系等。在临床上应对相关危险因素进行有效控制,同时给予有针对性的防治措施以此来降低AML患儿在化疗期间症状群的发生风险。

关键词：急性髓系白血病化疗症状群影响因素

Characterization of physicochemical and immunogenic properties of allergenic proteins altered by food processing:a review

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Food Science and Human Wellness 2024年第3期13卷 1135-1151页

作者： Enning zhou Qiangqiang li dan Zhu Gang Chen liming Wu Institute of Apicultural Research Chinese Academy of Agricultural SciencesBeijing 100093China Department of Food Science University of OtagoDunedin 9016New Zealand School of Food and Health Beijing Technology and Business UniversityBeijing 100048China

Food allergens are mainly naturally-occurring proteins with immunoglobulin E(IgE)-binding *** the structural and immunogenic characteristics of allergenic proteins is essential in assessing whether and how food processing techniques reduce *** here discuss the impacts of food processing technologies on the modification of physicochemical,structural,and immunogenic properties of allergenic *** techniques for characterizing changes in these properties of food allergens are *** processing helps to reduce allergenicity by aggregating or denaturing proteins,which masks,modifies,or destroys antigenic epitopes,whereas,it cannot eliminate allergenicity completely,and sometimes even improves allergenicity by exposing new ***,most food processing techniques have been tested on purified food allergens rather than food products due to potential interference of other food *** provide guidance for further development of processing operations that can decrease the allergenicity of allergenic food proteins without negatively impacting the nutritional profile.

关键词： Food allergens Protein structural characterization Immunogenicity evaluation Food processing modification

Experimental Observation of Near-Field Deterioration Induced by Stimulated Rotational Raman Scattering in Long Air Paths

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Chinese Physics Letters 2011年第6期28卷 137-140页

作者： WANG Jing ZHANG Xiao-Min HAN Wei li Fu-Quan zhou li-dan FENG Bin XIANG Yong Research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900

We report the experimental investigation of a stimulated rotational Raman scattering effect in long air paths on SG-III TIL,with a 1053 nm,20-cm-diameter,linearly polarized,3 ns flat-topped laser *** intense speckle pattern of near field with thickly dotted hot spots is observed at the end of propagation with an intensity-length product above 17 TW/*** Stokes developing from the scattering of the laser beam by quantum fluctuations is characterized by a combination of high spatial frequency *** observed speckle pattern with small-diameter hot spots results from the combination of the nonlinear Raman amplification and the linear diffraction propagation effect of the Stokes with a noise pattern arising from the spontaneous Raman scattering.A new promising suppression concept based on the special characteristic of the Stokes,called active and selective filtering of Stokes,is proposed.

关键词： speckle filtering intense

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秭归县农药化肥减量主要做法及成效

湖北植保 2024年第5期 62-64,77页

作者：胡端娥李文君周丹丽周玉枝刘宇卢会平秭归县农业科技服务中心湖北秭归443600

为促进绿色农业高质量发展,秭归县开展了化肥农药减量增效行动,取得了化肥农药使用量明显减少、耕地质量显著提升等成效。本文阐述了秭归县近几年的做法与成效,并提出了下一步做法建议,为实现农业转型升级和可持续发展提供参考。

关键词：化肥农药措施绿色发展

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Temporal,Spectral and Spatial Characterization of High-Energy Laser Pulse with Small Bandwidth Propagating through Long Path

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Chinese Physics Letters 2012年第12期29卷 112-115页

作者： DENG Xue-Wei WANG Fang JIA Huai-Ting XIANG Yong FENG Bin li Ke-Yu zhou li-dan Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900

Temporal,spectral and spatial characters of 0.3-nm-bandwidth high-energy laser pulse propagating through a long path are studied in detail in one newly constructed beamline of our laser *** evolution of propagation,pulse energy and near-field deterioration are analyzed theoretically and *** argon for air is demonstrated effectively to suppress stimulated rotational Raman scattering and the experimental result provides operating criterion,and engineering parameters for the under-constructed beamlines.

关键词： scattering Small Spatial

Compound events of heatwave and dust storm in the Taklamakan Desert

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Science China Earth Sciences 2024年第7期67卷 2073-2083页

作者： Yuzhi liU Jianping HUANG Ziyuan TAN Chenglong zhou dan li Yongkun XIE Key Laboratory for Semi-Arid Climate Change of the Ministry of Education Lanzhou UniversityLanzhou 730000China Collaborative Innovation Center for Western Ecological Safety Lanzhou UniversityLanzhou 730000China Taklamakan National Station of Observation and Research for Desert Meteorology in Xinjiang Urumqi 830002China

Taklamakan Desert(TD)has been characterized by numerous heatwaves and dust storms,leading to negative effects on societies and ecosystems at regional and global ***,the association between heatwaves and dust storms is poorly *** this study,we describe the association between heatwaves and dust events and propose a mechanism for such compound events in the *** results show that,from 1993 to 2022,the frequency and intensity of heatwaves in the TD have increased at a rate of 0.21 days year^(-1)and 0.02℃ year^(-1),*** than 40% of heatwaves existed with dust events,which significantly lagged behind ***,the higher the air temperature,the hotter and drier the soil,leading to more dust emissions in the *** high-occurrence heatwave years,a large-scale wave train of“cyclone-anticyclone-cyclone”in the northwest-southeast direction was found,with the anticyclone of which hovered over the TD *** anomalous anticyclones favored the formation and maintenance of heatwaves,and subsequent anomalous cyclones in the wave train triggered strong dust events followed by *** climate warming,the compound events of heatwave and dust storm are becoming bigger hazards threatening the socioeconomic and ecological security in the TD,the profound study of which is critical to understanding regional extreme responses.

关键词： Heatwave Dust storm Compound events Taklamakan Desert