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空气雾化喷嘴喷雾特性实验研究

工程热物理学报 2024年第3期45卷 873-878页

作者：陈方备王畅戴铮崔燚吴健哈尔滨工业大学能源科学与工程学院哈尔滨150001 上海飞机设计研究院上海201210

基于在低温环境下使用空气雾化喷嘴进行喷雾结冰实验的实际需求,在喷嘴投入使用前,标定了日本雾的池内公司生产的BIMJ 7004型空气雾化喷嘴的喷雾特性,包括各工况下的压缩空气流量、水流量,喷雾锥角和液滴群中值体积直径(MVD),并重点探... 详细信息

基于在低温环境下使用空气雾化喷嘴进行喷雾结冰实验的实际需求,在喷嘴投入使用前,标定了日本雾的池内公司生产的BIMJ 7004型空气雾化喷嘴的喷雾特性,包括各工况下的压缩空气流量、水流量,喷雾锥角和液滴群中值体积直径(MVD),并重点探究了环境温度对MVD的影响。实验结果表明,喷嘴喷雾的MVD受喷嘴气路和水路入口压力的影响最大,且基本不受环境温度的影响,即在0-20℃的环境温度下,喷雾距离D=0.8 m时,喷雾中心线处的液滴蒸发对MVD的影响很小。

关键词：喷雾特性标定 MVD 环境温度

基于马尔科夫模型的双站激光微波混合链路性能分析

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电子学报 2024年第2期52卷 468-476页

作者：邵军虎杜旭晓庞健史魏征西安理工大学自动化与信息工程学院西安市无线光通信与网络研究重点实验室陕西西安710048 华侨大学厦门市移动多媒体通信重点实验室福建厦门361021

针对气象变化对自由空间光(Free Space Optical,FSO)通信链路和毫米波射频(Radio Frequency,RF)通信链路可用率的影响问题,采用马尔科夫建模与稳态概率求解计算方法,分析不同天气条件下FSO/RF混合链路的双接收站分集与中断概率性能.基于... 详细信息

针对气象变化对自由空间光(Free Space Optical,FSO)通信链路和毫米波射频(Radio Frequency,RF)通信链路可用率的影响问题,采用马尔科夫建模与稳态概率求解计算方法,分析不同天气条件下FSO/RF混合链路的双接收站分集与中断概率性能.基于FSO链路和RF链路的信道模型,采用有限状态马尔科夫链(Finite State Markov Chain,FSMC)分别对单双站FSO/RF混合链路的切换选择进行建模,推导得出不同参数和天气情况下系统稳态的中断概率表达式.数值计算结果表明,当中断概率达到10^(-6),雨雾天气链路距离为1~7 km时,双站FSO/RF混合链路相比单站可获得4~25 dB的增益.

关键词： FSO/RF混合链路多站分集马尔科夫模型中断概率误码率

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光纤法珀传感器的改进型相位生成载波法解调

中国光学（中英文） 2024年第2期17卷 312-323页

作者：周朕蕊张国强邱宗甲郭少朋李群邵剑吴鹏陆云才中国科学院电工研究所北京100190 中国科学院大学北京100049 国网江苏省电力有限公司电力科学研究院江苏南京211102

为解决相位生成载波-反正切解调算法(PGC-Atan)的非线性失真问题,搭建了基于改进型PGC-Atan算法的非本征型法珀传感器(EFPI)解调系统。首先,理论分析了载波相位调制深度(C)偏离最优值、伴生调幅、载波相位延迟等非线性因素对经典PGC-Ata... 详细信息

为解决相位生成载波-反正切解调算法(PGC-Atan)的非线性失真问题,搭建了基于改进型PGC-Atan算法的非本征型法珀传感器(EFPI)解调系统。首先,理论分析了载波相位调制深度(C)偏离最优值、伴生调幅、载波相位延迟等非线性因素对经典PGC-Atan算法中参与反正切运算的正弦与余弦两路信号的影响。然后,针对外调制或伴生调幅较小的情况,提出了一种基于系数补偿的改进型PGC-Atan算法(PGC-CC-Atan)。该算法通过构造与C值和载波相位延迟有关的系数,消除反正切运算中的非线性参数。针对内调制情况,提出了一种基于椭圆拟合的改进型PGC-Atan算法(PGCEF-Atan)。该算法通过基于分块矩阵的最小二乘法拟合椭圆并提取3个椭圆参数,进而将受非线性因素影响的正弦与余弦两路信号校正为正交信号。最后,通过仿真验证了改进型算法的正确性,并采用高调制特性的垂直腔面发射激光器(VCSEL)和常规腔长的EFPI等搭建PGC解调系统,对比经典PGC-Atan算法与两种改进型算法的解调性能,证实了改进型算法非线性失真抑制的有效性。实验结果表明:一定C值范围内,两种改进型算法可在非线性因素影响下有效解调。PGC-EF-Atan算法相较于PGC-CC-Atan算法,解调信纳比提升了11.602 dB,总谐波失真降低了10.951%。两种改进型算法中,PGC-EF-Atan算法对非线性失真的抑制效果更好,且解调线性度良好,准确度高。

关键词：相位生成载波解调非线性失真椭圆拟合光纤法珀传感器

Microbiota enterotoxigenic Bacteroides fragilis-secreted BFT-1 promotes breast cancer cell stemness and chemoresistance through its functional receptor NOD1

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Protein & Cell 2024年第6期15卷 419-440页

作者： Wei Ma Lu Zhang Weilong Chen Zhaoxia chang Juchuanli Tu Yuanyuan Qin Yuwen Yao Mengxue Dong Jiajun Ding Siqin Li Fengkai Li Qiaodan Deng Yifei Yang Tingting Feng Fanrong Zhang Xiying shao Xueyan He Lixing Zhang Guohong Hu Quentin Liu Yi-Zhou jiang Shu Zhu Zhi Xiao Dan Su Tong Liu Suling Liu Fudan University Shanghai Cancer Center & Institutes of Biomedical Sciences State Key Laboratory of Genetic EngineeringCancer InstitutesDepartment of OncologyKey Laboratory of Breast Cancer in ShanghaiThe Shanghai Key Laboratory of Medical EpigeneticsShanghai Key Laboratory of Radiation OncologyThe International Co-laboratory of Medical Epigenetics and MetabolismMinistry of Science and TechnologyShanghai Medical CollegeFudan UniversityShanghai 200032China Intelligent Pathology Institute and Department of Pathology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230071China Department of Thyroid Breast and Vascular SurgeryXijing HospitalFourth Military Medical UniversityXi’an 710032China Institute of Immunology CAS Key Laboratory of Innate Immunity and Chronic DiseaseSchool of Basic Medical SciencesDivision of Life Science and MedicineUniversity of Science and Technology of ChinaHefei 230027China Department of Pathology The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital)Institute of Basic Medicine and Cancer (IBMC)Chinese Academy of SciencesHangzhou 310022China Department of Breast Surgery The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital)Institute of Basic Medicine and Cancer (IBMC)Chinese Academy of SciencesHangzhou 310022China Department of Breast Medical Oncology The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital)Institute of Basic Medicine and Cancer (IBMC)Chinese Academy of SciencesHangzhou 310022China Shanghai Institute of Nutrition and Health University of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200031China Sun Yat-sen University Cancer Center State Key Laboratory of Oncology in South ChinaGuangzhou 510060China Department of Breast Surgery Xiangya HospitalChangsha 410008China Department of Breast Surgery Tumor Hospital of Harbin Medic

Tumor-resident microbiota in breast cancer promotes cancer initiation and malignant progression.However,targeting microbiota to improve the effects of breast cancer therapy has not been investigated in detail.Here,we evaluated the microbiota composition of breast tumors and found that enterotoxigenic Bacteroides fragilis(ETBF)was highly enriched in the tumors of patients who did not respond to taxane-based neoadjuvant chemotherapy.ETBF,albeit at low biomass,secreted the toxic protein BFT-1 to promote breast cancer cell stemness and chemoresistance.Mechanistic studies showed that BFT-1 directly bound to NOD1 and stabilized NOD1 protein.NOD1 was highly expressed on ALDH+breast cancer stem cells(BCSCs)and cooperated with GAK to phosphorylate NUMB and promote its lysosomal degradation,thereby activating the NOTCH1-HEY1 signaling pathway to increase BCSCs.NOD1 inhibition and ETBF clearance increase the chemosensitivity of breast cancer by impairing BCSCs.

关键词： NOD1 breast chemotherapy

政策激励与农户水土保持技术采用——来自黄河流域陕西省农户的实证分析

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江西财经大学学报 2024年第3期 91-101页

作者：毛慧陈绍俭付咏陕西师范大学西北历史环境与经济社会发展研究院陕西西安710119 西安交通大学经济与金融学院陕西西安710049 南京农业大学经济管理学院江苏南京210095

水土流失直接关系着农业生产和农民生活,采用水土保持技术能有效提高农业生产力、促进农业可持续发展,政策激励可能影响农户的水土保持技术采用决策。根据对陕西省622户农户进行的微观调查数据,研究发现政策激励显著促进农户水土保持技... 详细信息

水土流失直接关系着农业生产和农民生活,采用水土保持技术能有效提高农业生产力、促进农业可持续发展,政策激励可能影响农户的水土保持技术采用决策。根据对陕西省622户农户进行的微观调查数据,研究发现政策激励显著促进农户水土保持技术采用行为。这一促进作用通过提高农户对水土保持技术生态效益和经济效益的认知实现。进一步研究发现,不同政策激励(技术培训、技术补贴、技术示范)均能显著促进农户采用水土保持技术,且政策激励对农户采用不同属性的水土保持技术均有显著促进作用。异质性分析表明,政策激励对农户水土保持技术采用行为的促进作用在专业化程度高、受教育程度高、经营规模大、受灾程度高的农户中表现更为明显。政府应通过加大宣传、丰富技术推广形式、完善补贴制度、针对不同属性采取差异的政策激励等方式引导和促进农户采用水土保持技术。

关键词：政策激励水土保持技术技术认知可持续农业

质子交换膜燃料电池极板及其表面改性研究进展

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稀有金属材料与工程 2024年第3期53卷 902-932页

作者：王瑜邵文婷武上焜杨巍陈建西安工业大学材料与化工学院陕西西安710021

在质子交换膜燃料电池(proton exchange membrane fuel cells,PEMFCs)的部件中,双极板(bipolar plates,BPs)是重要组成部分。双极板约占燃料电池成本、质量、体积的40%、80%、50%。传统的PEMFCs因为石墨双极板的材料、工艺等问题,造成... 详细信息

在质子交换膜燃料电池(proton exchange membrane fuel cells,PEMFCs)的部件中,双极板(bipolar plates,BPs)是重要组成部分。双极板约占燃料电池成本、质量、体积的40%、80%、50%。传统的PEMFCs因为石墨双极板的材料、工艺等问题,造成其体积和质量较大,这增加了汽车的重量,缩小了汽车底盘的可用空间,影响了质子交换膜燃料电池汽车的性能。因此开发体积小、成本低、制备工艺简单的双极板对推进质子交换膜燃料电池的商业化应用具有重要意义。金属双极板因其成本低、力学性能好、导电性、导热性、体积相对易控等特点,在PEMFCs领域备受关注。但金属双极板在PEMFCs环境中易生成钝化膜,导致其接触电阻增加。因此,如何在提高金属双极板耐蚀性的同时,保持良好的导电性,是当前对PEMFCs研究的重点。本文综述了石墨、复合材料和金属双极板制备工艺及表面改性方法。讨论了双极板及其表面碳化物涂层、金属涂层和氮化物涂层的优缺点,并比较了这些涂层在PEMFCs环境下的耐腐蚀性和界面接触电阻性能。

关键词：质子交换膜燃料电池双极板表面改性涂层导电性耐蚀性

复杂环境下电磁目标信号认知处理架构与应用研究

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电子科技大学学报 2024年第1期53卷 40-49页

作者：张伟李想翟志凯张谦邵怀宗孟建电子科技大学电磁认知与应用研究中心成都611731 电子信息控制重点实验室成都610036 电磁空间认知与智能控制技术实验室北京100089

针对现代电磁频谱设备或终端具有网络化、捷变性、多功能、自适应、种类复杂多样和使用环境复杂多变等特性给认知电磁频谱战系统的信号分析与处理带来的巨大挑战的问题,提出了一种结合人工智能、适合复杂电磁环境下电磁目标信号认知处... 详细信息

针对现代电磁频谱设备或终端具有网络化、捷变性、多功能、自适应、种类复杂多样和使用环境复杂多变等特性给认知电磁频谱战系统的信号分析与处理带来的巨大挑战的问题,提出了一种结合人工智能、适合复杂电磁环境下电磁目标信号认知处理与分析的架构。在该架构下电磁目标信号分析与处理被分为目标信号参数估计、目标信号类型分类、辐射源个体识别和目标信号的特征建库与知识图谱[1-3]的构建等4个层次,可以很好适应闭集和开集电磁目标信号的分析与处理;此外,在此架构下提出了未知辐射源辨识、跨模态辐射源智能识别和电磁辐射源的个体识别的算法框架,在实测数据集上的验证实验表明,该算法在闭集和开集电磁信号分析中有效可行。

关键词：电磁频谱战认知处理架构电磁目标知识图谱与推理辐射源个体识别

多效TiO_(2)/3DG复合材料对四环素废水的处理

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水处理技术 2024年第1期50卷 72-75页

作者：杨扬刘畅王剑自然资源部天津海水淡化与综合利用研究所 300192 天津市药品检验研究院天津300070

实验以钛酸四丁酯、氧化石墨烯为主要原料,采用溶剂热法制备TiO_(2)/3DG复合材料,以四环素为目标降解污染物。用扫描电子显微镜(SEM)、紫外-可见-近红外光谱(UV-Vis-NIR)、X射线衍射光谱(XRD)对复合物进行表征。结果显示,TiO_(2)均匀地... 详细信息

实验以钛酸四丁酯、氧化石墨烯为主要原料,采用溶剂热法制备TiO_(2)/3DG复合材料,以四环素为目标降解污染物。用扫描电子显微镜(SEM)、紫外-可见-近红外光谱(UV-Vis-NIR)、X射线衍射光谱(XRD)对复合物进行表征。结果显示,TiO_(2)均匀地负载在GO表面,并在整个波段具有很好的光吸收性能。研究了TiO_(2)-3DG通过吸附、光热转换和光催化方式对四环素的处理情况。结果表明,复合材料具有多效处理能力,具有吸附、光热转换和光催化的多重效果。对于四环素,单位质量吸附量为100.9 mg/g,光热转换效率为87.5%,2 h脱除率为94.7%。

关键词：氧化石墨烯 TiO_(2) 吸附催化光热转换

Incidence and prognosis of olfactory and gustatory dysfunctions related to SARS-CoV-2 Omicron strain infection in China:A national multicenter survey of 35,566 individuals

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 113-120页

作者： Meng-Fan Liu Rui-Xia Ma Xian-Bao Cao Hua Zhang Shui-Hong Zhou Wei-Hong jiang Yan jiang Jing-Wu Sun Qin-Tai Yang Xue-Zhong Li Ya-Nan Sun Li Shi Min Wang Xi-Cheng Song Fu-Quan Chen Xiao-Shu Zhang Hong-Quan Wei shao-Qing Yu Dong-Dong Zhu Luo Ba Zhi-Wei Cao Xu-Ping Xiao Xin Wei Zhi-Hong Lin Feng-Hong Chen Chun-Guang Shan Guang-Ke Wang Jing Ye Shen-Hong Qu chang-Qing Zhao Zhen-Lin Wang Hua-Bin Li Feng Liu Xiao-Bo Cui Sheng-Nan Ye Zheng Liu Yu Xu Xiao Cai Wei Huang Ru-Xin Zhang Yu-Lin Zhao Guo-Dong Yu Guang-Gang Shi Mei-Ping Lu Yang Shen Yu-Tong Zhao Jia-Hong Pei shao-Bing Xie Long-Gang Yu Ye-Hai Liu shao-Wei Gu Yu-Cheng Yang Lei Cheng jian-Feng liu Graduate School of Beijing University of Chinese Medicine BeijingChina Department of Otorhinolaryngology Head and Neck Surgery China-Japan Friendship HospitalBeijingChina Department of Otorhinolaryngology Head and Neck Surgery The First People's Hospital of YinchuanYinchuanChina Department of Otorhinolaryngology The First People's Hospital of Yunnan ProvinceKunmingChina Department of Otorhinolaryngology The First Affiliated Hospital of Xinjiang Medical UniversityUrumqiChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina Department of Otorhinolaryngology Head and Neck Surgery Xiangya Hospital Central South UniversityChangshaChina Department of Otorhinolaryngology Head and Neck Surgery The Affiliated Hospital of Qingdao UniversityQingdaoChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of USTCHefeiChina Department of Otorhinolaryngology Head and Neck Surgery The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Department of Otorhinolaryngology Head and Neck Surgery Qilu Hospital of Shandong UniversityJinanChina Department of Otorhinolaryngology Head and Neck Surgery The Second Affiliated Hospital of Harbin Medical UniversityHarbinChina Department of Otolaryngology The Second Hospital of Shandong UniversityShandong UniversityJinanChina Department of Otorhinolaryngology Head and Neck Surgery Peking University People's HospitalBeijingChina Department of Otorhinolaryngology Head and Neck Surgery Yantai Yuhuangding HospitalQingdao UniversityYantaiChina Department of Otorhinolaryngology Head and Neck Surgery Xijing HospitalThe Fourth Military Medical UniversityXi'anChina Gansu Provincial Center for Disease Control and Prevention LanzhouChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of China Medical UniversityShenyangChina Department of Otorhinolaryngology Head and Neck Surgery Tongji Hospit

Objective:This cross-sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID-19 in China.Methods:This study was conducted by 45 tertiary Grade-A hospitals in China.Online and offline questionnaire data were obtained from patients infected with COVID-19 between December 28,2022,and February 21,2023.The collected information included basic demographics,medical history,smoking and drinking history,vaccination history,changes in olfactory and gustatory functions before and after infection,and other postinfection symptoms,as well as the duration and improvement status of olfactory and gustatory disorders.Results:Complete questionnaires were obtained from 35,566 subjects.The overall incidence of olfactory and taste dysfunction was 67.75%.Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste dysfunction.Having received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such dysfunction.Before infection,the average olfactory and taste VAS scores were 8.41 and 8.51,respectively;after infection,they decreased to 3.69 and 4.29 and recovered to 5.83 and 6.55 by the time of the survey.The median duration of dysosmia and dysgeusia was 15 and 12 days,respectively,with 0.5%of patients having symptoms lasting for more than 28 days.The overall self-reported improvement rate was 59.16%.Recovery was higher in males,never smokers,those who received two or three vaccine doses,and those that had never experienced dental health issues,or chronic accompanying symptoms.Conclusions:The incidence of dysosmia and dysgeusia following infection with the SARS-CoV-2 virus is high in China.Incidence and prognosis are influenced by several factors,including sex,SARS-CoV-2 vaccination,history of head-facial trauma,nasal and oral health status,smoking and drinking history,and the persistence of accompanying symptoms.

关键词： epidemiologic studies incidence olfactory disorders prognosis SARS-CoV-2 taste disorders