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Nano Research 2024年第6期17卷 4943-4950页

作者： Rui Li Xiayan Yan Meng Liu Qingkai Zhao Jie Du Xinxin Tan Jingwen Ba Rongguang Zeng wenhua luo Jingsong Xu Institute of Materials China Academy of Engineering PhysicsJiangyou 621907China Science and Technology on Surface Physics and Chemistry Laboratory Jiangyou 621908China

Top-down strategy has been widely applied for synthesis of metal single atom catalysts(SACs)via converting metal nanoparticles or bulk metals into atomically dispersed ***,we report a simple electrochemical atomic migration strategy for top-down synthesis of SACs via a facile cathodic corrosion process without involving high temperature or harsh *** of metal nanoparticles on cathode are firstly disbanded under high negative voltage,and emitted into the electrolyte in the form of atomic metal anions in Zintl *** escaped atomically dispersed metal species are then oxidized by water molecules and captured by the defects on the pre-added nitrogen doped carbon carriers in the *** cathodic corrosion strategy is confirmed to be suitable for scalable synthesis of kinds of metal SACs(e.g.,Pt,Pd,and Ir)on doped carbon ***,the as-prepared nitrogen doped carbon powder supported Pt SACs exhibit superior catalytic activity toward hydrogen evolution reaction(HER)with a low overpotential of 0.024 V at 10 mA·cm^(−2)and a low Tafel slope of 29.7 mV·dec^(−1)as well as a long-term durability.

关键词： cathodic corrosion top-down strategy powdery single atom catalysts hydrogen evolution reaction scalable synthesis

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基于联邦学习与卷积神经网络的入侵检测模型

信息安全研究 2024年第7期10卷 642-648页

作者：罗文华张晓龙中国刑事警察学院公安信息技术与情报学院沈阳110035

网络入侵检测模型需要在大规模的网络流量数据中及时准确地识别出恶意数据,但单一机构的标签数据不足,各机构之间不愿共享数据,导致训练出的入侵检测模型性能不高.针对上述问题,提出一种基于联邦学习和1维卷积神经网络的入侵检测模型FL-... 详细信息

网络入侵检测模型需要在大规模的网络流量数据中及时准确地识别出恶意数据,但单一机构的标签数据不足,各机构之间不愿共享数据,导致训练出的入侵检测模型性能不高.针对上述问题,提出一种基于联邦学习和1维卷积神经网络的入侵检测模型FL-1DCNN,在保证较高检测精度的同时,允许更多的参与方保护自身数据的隐私和安全,解决了标签数据不足的问题.FL-1DCNN模型首先对原始数据集进行一系列预处理操作,然后在联邦学习机制下将1维卷积神经网络作为各参与方的通用模型进行特征提取,最后通过Sigmoid分类器进行二分类.实验结果表明,FL-1DCNN模型在CICIDS2017数据集上的准确率达到96.5%,F1分数达到97.9%.此外,相较于传统集中式学习训练出的模型1DCNN,FL-1DCNN模型在训练时间上缩短了32.7%.

关键词：入侵检测联邦学习深度学习卷积神经网络 CICIDS2017数据集

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利用动态裁剪差分隐私实现联邦学习入侵检测

小型微型计算机系统 2024年第6期45卷 1474-1481页

作者：张晓龙罗文华中国刑事警察学院公安信息技术与情报学院沈阳110035

网络入侵检测任务中应用联邦学习技术可以在参与方数据本地化的同时扩充标签数据数量,以此得到性能更优的检测模型.然而,联邦学习训练过程通常涉及服务器与参与方之间的多次交互,而在交互过程中,参与方上传的参数容易受到攻击者的恶意窃... 详细信息

网络入侵检测任务中应用联邦学习技术可以在参与方数据本地化的同时扩充标签数据数量,以此得到性能更优的检测模型.然而,联邦学习训练过程通常涉及服务器与参与方之间的多次交互,而在交互过程中,参与方上传的参数容易受到攻击者的恶意窃取,造成数据隐私泄漏.针对此问题,提出了一种基于动态梯度裁剪的差分隐私保护方法 DCDP,DCDP选取训练过程中梯度的L2范数分位数作为裁剪阈值,之后通过参数噪声传递实现参与方数据隐私保护,保证了噪声添加合理性,从而避免手动设置阈值造成的性能受损.改进联邦平均算法FedAvg,添加Macro-F1指标进行加权聚合,得到新的网络入侵检测算法DCDP-FedF1.通过在CICIDS2017数据集上进行对比实验,证明了DCDP-FedF1的有效性和先进性.

关键词：入侵检测联邦学习差分隐私动态梯度裁剪

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基于正交试验的2种广西特有秋海棠扦插繁殖

林业科技通讯 2024年第5期 47-50页

作者：陆奇丰骆文华广西壮族自治区中国科学院广西植物研究所广西桂林541006

研究以广西秋海棠(Begonia guangxiensis)和橙花侧膜秋海棠(***)的健康成熟叶片为繁殖材料,以珍珠岩、蛭石和河沙为扦插基质,以3-吲哚乙酸(IAA)和萘乙酸(NAA)为生长调节剂,采用L9(3~3)正交试验设计,探讨3种生长调节剂(IAA、NAA、IAA和NA... 详细信息

研究以广西秋海棠(Begonia guangxiensis)和橙花侧膜秋海棠(***)的健康成熟叶片为繁殖材料,以珍珠岩、蛭石和河沙为扦插基质,以3-吲哚乙酸(IAA)和萘乙酸(NAA)为生长调节剂,采用L9(3~3)正交试验设计,探讨3种生长调节剂(IAA、NAA、IAA和NAA等量混合)及3种不同处理浓度下(100、200和300 mg/L)对橙花侧膜秋海棠和广西秋海棠叶片扦插的成活率、出苗率和生根效果的影响。结果表明,扦插基质对橙花侧膜秋海棠和广西秋海棠的生根效果有显著影响(P0.05)。根据极差分析结果,橙花侧膜秋海棠叶片最优扦插组合为:浓度为200 mg/L的IAA激素+蛭石基质;广西秋海棠叶片最优扦插组合为:浓度为100 mg/L的IAA和NAA混合溶液+河沙基质。该结果可为橙花侧膜秋海棠和广西秋海棠叶片扦插快繁提供参考。

关键词：广西秋海棠 Begonia guangxiensis 橙花侧膜秋海棠 B.aurantiflora 正交试验叶片扦插

Cathodic corrosion as a facile and universal method for the preparation of supported metal single atoms

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Nano Research 2022年第3期15卷 1838-1844页

作者： Rui Li Jingsong Xu Qingkai Zhao Wensheng Ren Rongguang Zeng Qifa Pan Xiayan Yan Jingwen Ba Tao Tang wenhua luo Institute of Materials China Academy of Engineering PhysicsJiangyou 621907China Science and Technology on Surface Physics and Chemistry Laboratory Jiangyou 621908China

Top-down strategy has been generally adopted for preparation of metal single atom catalysts(SACs)due to the simplified synthetic process,metal economics,and scalability ***,we propose a general top-down route to convert metal nanoparticles into uniformly dispersed metal single atoms in mild electrochemical environment via a facile cathodic corrosion *** the synthetic process,Pt nanoparticles precursors are transformed into migrating Pt single atoms(Pt1)driven by a high negative potential;and subsequently these mobile Pt atoms are trapped and stabilized by N coordination sites of N-doped carbon paper(NCP).The as-prepared Pt1/NCP electrodes exhibit a superior catalytic activity toward hydrogen evolution reaction(HER)with a low overpotential of 0.022 V at 10 mA/cm^(2)and a low Tafel slope of 28.5 mV/dec as well as a long-term ***,the proposed electrochemical atomic migration strategy shows a promising generality for fabricating other metal single atoms(e.g.,Pd,Ir,Cu),which may open a new avenue for metallic SACs preparation.

关键词： top-down strategy electrochemical atomic migration cathodic corrosion nitrogen doped carbon paper metal single atoms hydrogen evolution reaction

全基因组重测序解析重庆武隆中华蜜蜂遗传变异及种群分化特征

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福建农林大学学报（自然科学版） 2024年第2期53卷 254-266页

作者：任勤姬聪慧龙小飞罗文华王瑞生陈恒高丽娇曹兰刘佳霖重庆市畜牧科学院重庆402460 重庆市武隆区畜牧技术推广站重庆408500

【目的】解析重庆武隆中华蜜蜂的遗传变异及种群分化特征,为该地区传粉昆虫的遗传多样性研究提供理论参考。【方法】对重庆武隆中华蜜蜂进行全基因组重测序,并结合我国其他地区57群中华蜜蜂的重测序原始数据进行种群遗传分化分析。【结... 详细信息

【目的】解析重庆武隆中华蜜蜂的遗传变异及种群分化特征,为该地区传粉昆虫的遗传多样性研究提供理论参考。【方法】对重庆武隆中华蜜蜂进行全基因组重测序,并结合我国其他地区57群中华蜜蜂的重测序原始数据进行种群遗传分化分析。【结果】测序共获得武隆中华蜜蜂有效数据(clean data)33.53 Gb,发现高质量单核苷酸多态性(SNP)位点共3886321个,小片段的插入与缺失(small indel)位点1392028个。在武隆中华蜜蜂样品中筛选出具有相同变异位点的非同义SNP突变基因589个,编码区发生small indel的基因214个。这些基因主要富集于赖氨酸降解、轴突导向、细胞外基质受体互作和丝裂原活化蛋白激酶信号通路。最终获得16个具有相同SNP和small indel的突变基因,其中包括嗅觉受体基因2个、细胞色素P450基因1个。武隆中华蜜蜂与我国其他地理型中华蜜蜂可能存在显著的遗传分化,与华中中蜂和北方中蜂(陕西安康)种群的亲缘关系较近。【结论】推测氨基酸代谢、神经系统发育、嗅觉进化、抗逆性能改善以及对温度偏好性的转变与武隆中华蜜蜂适应重庆本地自然环境有关。随意引种可能导致优质中华蜜蜂品种混杂,生产性能和抗逆性能下降。因此,需要保护本土优质中华蜜蜂种质资源。

关键词：中华蜜蜂全基因组重测序遗传多样性环境适应机制亲缘关系

Regulating local chemistry in ZrCo-based orthorhombic hydrides via increasing atomic interference for ultra-stable hydrogen isotopes storage

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Journal of Energy Chemistry 2022年第6期31卷 397-405,I0011页

作者： Zhaoqing Liang Zhendong Yao Ruhong Li Xuezhang Xiao Zhichao Ye Xuancheng Wang Jiacheng Qi Jiapeng Bi Xiulin Fan Huaqin Kou wenhua luo Changan Chen Lixin Chen State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027ZhejiangChina Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province Hangzhou 310013ZhejiangChina Institute of Materials China Academy of Engineering PhysicsMianyang 621907SichuanChina State Key Laboratory of Surface Physics and Chemistry Mianyang 621907SichuanChina

Developing a universal and reliable strategy for the modulation of composition and structure of energy storage materials with stable cycling performance is vital for hydrogen and its isotopes storage advanced system,yet still ***,an ultra-stable lattice structure is designed and verified to increase atomic chaos and interference for effectively inhibiting disproportionation reaction and improving cycling stability in ZrCo-based hydrogen isotopes storage *** screening in terms of configuration entropy calculation,we construct Zr_(1-2)Nb_(x)Co_(1-2x)Cu_(x)Ni_(x)(x=0.15,0.2,0.25) alloys with increased atomic chaos,and successfully achieve stable isostructural de-/hydrogenation during 100 cycles,whose cycling capacity retentions are above 99%,much higher than 22.4%of pristine ZrCo *** theoretical analysis and experimental evidences indicate the high thermo-stability of orthorhombic lattice in Zr_(0.8)Nb_(0.2)Co_(0.6)Cu_(0.2)Ni_(0.2) ***,the increased atomic chaos and interference in Zr_(0.8)Nb_(0.2)Co_(0.6)Cu_(0.2)Ni_(0.2) alloy causes regulation in hydrogen local chemical neighborhood,thereby confusing the hydrogen release order,which effectively eliminates lattice distortion and unlocks an ultrastable lattice *** study provides a new and comprehensive inspiration for hydrogen atoms transport behaviors and intrinsic reason of stable orthorhombic transformation,which can contribute to paving the way for other energy storage materials modulation.

关键词： ZrCo alloy High configuration entropy Regulating chemical environment Lattice stabilization In-situ XRD Density functional theory

An efficient approach for the treatment of radioactive waste perfluoropolyether lubricants via a synergistic effect of thermal catalysis and immobilization

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Journal of Environmental Sciences 2024年第2期136卷 512-522页

作者： Xinhang Du wenhua Tong Xinyu Zhou Jia luo Yuqiu Liu Yabo Wang Panyu Li Yongkui Zhang Department of Pharmaceutical&Biological Engineering School of Chemical EngineeringSichuan UniversityChengdu 610065China

Perfluoropolyether(PFPE)lubricants are a kind of high-molecular polymer with many excellent ***,the use of PFPEs in the nuclear industry can lead to partial decomposition and carrying radionuclides,resulting in a large amount of radioactive waste PFPE lubricants ***,radioactive waste PFPE lubricants are difficult to be effectively treated due to their high stability,the risk of possible leakage of radionuclides,and hypertoxic fluorine-containing *** this study,without any precedent,a strategy of Mn O_(2)-catalyzed decomposition and Na_(2)CO_(3)-immobilized conversion was proposed for PFPE lubricant decomposition and fluorine immobilization simultaneously based on the Lewis acid-base and oxygen vacancies concept.A high fluorine conversion efficiency of 95.4%was ***,the mechanism of decomposition suggested that Mn O_(2)mainly provided Lewis acid sites and attacked the(basic)fluorine or oxygen atoms in PFPE *** decomposition of PFPE chains was proceed down and volatile fluorine-containing gas was released by partial electron transfer,intramolecular disproportionation reaction,and unzipping ***,gas by-products could be further oxidized and then immobilized into fluoride salts by carbonate solid ***,this study provides a simple,safe,and potentially practical strategy for the harmless conversion of refractory fluorinated organic wastes,especially perfluoropolymers.

关键词： Perfluoropolyether lubricants Catalyzed decomposition Fluorine-containing gas Immobilized conversion Fluoride

Decreased LDHB expression in breast tumor cells causes NK cell activation and promotes tumor progression

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Cancer Biology & Medicine 2024年第6期21卷 513-540页

作者： Zhihong luo Xiaohua Huang Xinyi Xu Kefeng Wei Yi Zheng Ke Gong wenhua Li Hubei Key Laboratory of Cell Homeostasis College of Life SciencesWuhan UniversityWuhan 430072China Wuhan University Shenzhen Research Institute Shenzhen 518057China Central Laboratory University of Chinese Academy of Sciences-Shenzhen HospitalShenzhen 518107China Hubei Province Key Laboratory of Allergy and Immunology and Department of Immunology School of Basic Medical SciencesWuhan UniversityWuhan 430071China

Objective: Abnormal metabolism is the underlying reason for breast cancer progression. Decreased lactate dehydrogenase B(LDHB) has been detected in breast cancer but the function of LDHB remains ***: Western blot was used to analyze LDHB expression in breast cancer cells. The impact of LDHB on tumor cell migration and invasion was determined using Transwell assays, wound healing assays, and a mouse lung metastasis model. Subcutaneous tumor formation, a natural killer(NK) cell cytotoxicity assay, and flow cytometry evaluated NK cell activation. Immunofluorescence and quantitative real-time PCR detected NK cell activation markers. Kaplan-Meier analysis evaluated the effect of immune cell infiltration on prognosis. Single-sample gene set enrichment analysis determined NK cell activation scores. A support vector machine predicted the role of LDHB in NK cell ***: In this study we showed that LDHB inhibits the breast cancer cell metastasis and orchestrates metabolic reprogramming within tumor cells. Our results revealed that LDHB-mediated lactic acid clearance in breast cancer cells triggers NK cell activation within the tumor microenvironment. Our findings, which were confirmed in a murine model, demonstrated that LDHB in tumor cells promotes NK cell activation and ultimately results in the eradication of malignant cells. Clinically, our study further validated that LDHB affects immune cell infiltration and function. Specifically, its expression has been linked to enhanced NK cell-mediated cytotoxicity and improved patient survival. Furthermore, we identified LDHB expression in tumors as an important predictor of NK cell activation, with strong predictive ability in some ***: Our results suggest that LDHB is a promising target for activating the tumor immune microenvironment in breast cancer, where LDHB-associated lactic acid clearance leads to increased NK cell activity. This study highlights the critical role of LDHB in regula

关键词： Breast cancer lactate dehydrogenase B lactic acid NK cells tumor immunity

祭祖与礼佛:紫禁城养心殿一区的佛堂与清帝的信仰

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故宫博物院院刊 2022年第1期237卷 89-103,134页

作者：罗文华故宫博物院宫廷历史部

自雍正以降,养心殿一区成为清代宫廷的政治枢纽和帝王生活起居之所,其中至少分布着四个佛堂区。通过对这些佛堂及其内部供奉的梳理,作者发现该区域的佛堂以藏传佛教佛堂规模最大;而同样以佛堂命名的东佛堂(东配殿),其实是以祭祖为主要... 详细信息

自雍正以降,养心殿一区成为清代宫廷的政治枢纽和帝王生活起居之所,其中至少分布着四个佛堂区。通过对这些佛堂及其内部供奉的梳理,作者发现该区域的佛堂以藏传佛教佛堂规模最大;而同样以佛堂命名的东佛堂(东配殿),其实是以祭祖为主要功能的亦佛堂亦宗庙的建筑;此外在养心殿天花上还供有雍正九年安奉的藏汉佛教与道教混合的五块一组符板。作者认为,养心殿一区佛堂体现出汉藏佛教、汉地传统祖先崇拜与清宫满族传统信仰等多元并存的现象,清帝在对待祭祖、佛教与道教方面表现出实用主义的态度。

关键词：养心殿西暖阁内佛堂东佛堂西佛堂神牌符板