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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 301-314页

作者： Zhanghao Wan Shiliang Yang desong kong Dongbo Li Jianhang Hu Hua Wang State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China Southwest Copper Branch Yunnan Copper Co.Ltd.Kunming 650102China

The variation characteristics of bubble morphology and the thermal-physical properties of bubble boundary in the top-blown smelting furnace were explored by means of the computational fluid dynamics method.The essential aspects of the fluid phase(e.g.,splashing volume,dead zone of copper slag,and gas penetration depth)were explored together with the effect of sinusoidal pulsating gas intake on the momentum-transfer performance between phases.The results illustrated that two relatively larger vortices and two smaller vortices appear in the bubble waist and below the lance,respectively.The expansion of larger ones as well as the shrinking of smaller ones combine to cause the contraction of the bubble waist.Compared to the results of the case with a fixed gas injection velocity(V_(g)=58 m/s),the splashing volume and dead zone volume of the slag under the V_(g)=58+10sin(2πt)condition are reduced by 24.9%and 23.5%,respectively,where t represents the instant time.Gas penetration depth and slag motion velocity of the latter are 1.03 and 1.31 times high-er than those of the former,respectively.

关键词： top-blown smelting furnace pulsed flow volume of fluid penetration depth splashing volume

Engineering oxygen vacancies on Tb-doped ceria supported Pt catalyst for hydrogen production through steam reforming of long-chain hydrocarbon fuels

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Chinese Journal of Chemical Engineering 2024年第4期68卷 181-192页

作者： Zhourong Xiao Changxuan Zhang Peng Li desong Wang Xiangwen Zhang Li Wang Jijun Zou Guozhu Li State Key Laboratory of Metastable Materials Science and Technology(MMST) Hebei Key Laboratory of Applied ChemistryCollege of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004China Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Steam reforming of long-chain hydrocarbon fuels for hydrogen production has received great attention for thermal management of the hypersonic vehicle and fuel-cell application.In this work,Pt catalysts supported on CeO_(2)and Tb-doped CeO_(2)were prepared by a precipitation method.The physical structure and chemical properties of the as-prepared catalysts were characterized by powder X-ray diffraction,scanning electron microscopy,transmission electron microscopy,Raman spectroscopy,H_(2)temperature programmed reduction,and X-ray photoelectron spectroscopy.The results show that Tb-doped CeO_(2)supported Pt possesses abundant surface oxygen vacancies,good inhibition of ceria sintering,and strong metal-support interaction compared with CeO_(2)supported Pt.The catalytic performance of hydrogen production via steam reforming of long-chain hydrocarbon fuels(n-dodecane)was tested.Compared with 2Pt/CeO_(2),2Pt/Ce_(0.9)Tb_(0.1)O_(2),and 2Pt/Ce_(0.5)Tb_(0.5)O_(2),the 2Pt/Ce_(0.7)Tb_(0.3)O_(2)has higher activity and stability for hydrogen production,on which the conversion of n-dodecane was maintained at about 53.2%after 600 min reaction under 700℃at liquid space velocity of 9 ml·g^(-1)·h^(-1).2Pt/CeO_(2)rapidly deactivated,the conversion of n-dodecane was reduced to only 41.6%after 600 min.

关键词： Steam reforming n-Dodecane Hydrogen production Pt-based catalyst Oxygen vacancy CeO_(2)

Naringenin is a Potential Immunomodulator for Inhibiting Liver Fibrosis by Inhibiting the cGAS-STING Pathway

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Journal of Clinical and Translational Hepatology 2023年第1期11卷 26-37页

作者： Li Chen Siwei Xia Shuqi Wang Yuanyuan Zhou Feixia Wang Zhanghao Li Yang Li desong kong Zili Zhang Jiangjuan Shao Xuefen Xu Feng Zhang Shizhong Zheng Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica School of PharmacyNanjing University of Chinese MedicineNanjingJiangsuChina Chinese Medicine Modernization and Big Data Research Center Nanjing University of Chinese MedicineNanjingJiangsuChina

Background and Aims:Naringenin is an anti-inflammatory flavonoid that has been studied in chronic liver disease.The mechanism specific to its antifibrosis activity needs further investigation This study was to focused on the cyclic guanosine monophosphate-adenosine monophosphate synthase(cGAS)pathway in hepatic stellate cells and clarified the antifibrosis mechanism of naringenin.Methods:The relationship between the cGAS-stimulator of interferon genes(STING)pathway and liver fibrosis was analyzed using the Gene Expression Omnibus database.Histopathology,immunohistochemistry,fluorescence staining,Western blotting and polymerase chain reaction were performed to assess gene and protein expression levels associated with the cGAS pathway in clinical liver tissue samples and mouse livers.Molecular docking was performed to evaluate the relationship between naringenin and cGAS,and western blotting was performed to study the expression of inflammatory factors downstream of cGAS in vitro.Results:Clinical database analyses showed that the cGAS-STING pathway is involved in the occurrence of chronic liver disease.Naringenin ameliorated liver injury and liver fibrosis,decreased collagen deposition and cGAS expression,and inhibited inflammation in carbon tetrachloride(CCl4)-treated mice.Molecular docking found that cGAS may be a direct target of naringenin.Consistent with the in vivo results,we verified the inhibitory effect of naringenin on activated hepatic stellate cells(HSCs).By using the cGAS-specific agonist double-stranded(ds)DNA,we showed that naringenin attenuated the activation of cGAS and its inflammatory factors affected by dsDNA.We verified that naringenin inhibited the cGAS-STING pathway,thereby reducing the secretion of inflammatory factors by HSCs to ameliorate liver fibrosis.Conclusions:Interrupting the cGAS-STING pathway helped reverse the fibrosis process.Naringenin has potential as an antihepatic fibrosis drug.

关键词： Liver fibrosis cGAS Naringenin Inflammation Hepatic stellate cells

碳源补充型高级氧化法工艺净化水中磺胺类抗生素研究进展与趋势

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生态环境学报 2024年第2期33卷 321-332页

作者：张德嵩陈振东孔德锦李柏林何晓曼杨列武汉理工大学资源与环境工程学院湖北武汉430070

磺胺类抗生素(SAs)是自然水环境和污水处理系统中检出频次与残留浓度最高的抗生素之一。过氧乙酸(PAA)作为广谱性杀菌剂,因其氧化性强、环境友好等优势,其用于有机污染物降解成为研究热点之一。与传统H2O2基芬顿法等无机氧化法相比,PAA... 详细信息

磺胺类抗生素(SAs)是自然水环境和污水处理系统中检出频次与残留浓度最高的抗生素之一。过氧乙酸(PAA)作为广谱性杀菌剂,因其氧化性强、环境友好等优势,其用于有机污染物降解成为研究热点之一。与传统H2O2基芬顿法等无机氧化法相比,PAA氧化反应生成乙酸,经中和后转化的乙酸钠可为后续生化工艺段提供优质碳源,有效降低含SAs废水的处理成本。该文对PAA基碳源补充型高级氧化法的研究进展与趋势进行了系统总结。以SAs作为典型水环境污染物,对近年来PAA基碳源补充型高级氧化工艺进行了系统总结分析,比较分析了其对各类水质背景中SAs的去除效能,并对过渡金属、碳基材料等多种PAA活化方式,工艺运行参数、活性氧物种(ROS)的交联作用机理以及SAs降解机制进行了剖析。研究发现,乙酰氧基自由基和乙酰过氧基自由基为PAA基高级氧化工艺中的基础活性物质,pH、PAA含量、共存物质等会不同程度上影响体系中ROS的生成路径。此外,磺胺类抗生素主要包括五元磺胺和六元磺胺,二者降解机理存在一定差异。五元磺胺降解主要依靠苯胺环上氨基氧化、羟基取代、S–N/S–C键断裂、N中心自由基偶联反应等4种途径;六元磺胺降解过程还包括SO_(2)脱除、斯迈尔斯重排等机制。在PAA基碳源补充型高级氧化工艺研究领域,新型高性能非均相PAA活化方式开发、实际工况的运行调控与成本控制等将成为未来研究热点。该文可为PAA基碳源补充型高级氧化工艺治理水环境新污染物的研究与应用方向提供参考。

关键词：磺胺类抗生素过氧乙酸高级氧化工艺自由基碳源

融合A^(*)与DWA算法的水面船艇动态路径规划

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仪器仪表学报 2024年第1期45卷 301-310页

作者：孙岩霆王荣杰蒋德松集美大学轮机工程学院厦门361021 福建省船舶与海洋工程重点实验室厦门361021

为解决水面船艇路径规划同时要求全局最优、实时避障和航迹安全可靠的问题,提出了一种基于融合A^(*)算法与动态窗口算法(DWA)的水面船艇路径规划方法。首先通过引入启发函数动态加权策略,提高A^(*)算法的搜索效率;然后综合考虑水面船艇... 详细信息

为解决水面船艇路径规划同时要求全局最优、实时避障和航迹安全可靠的问题,提出了一种基于融合A^(*)算法与动态窗口算法(DWA)的水面船艇路径规划方法。首先通过引入启发函数动态加权策略,提高A^(*)算法的搜索效率;然后综合考虑水面船艇的运动特性,采用一种路径转角节点角度削弱策略,减少转角,缩短全局路径长度;最后,基于全局因素影响与航迹安全约束对DWA算法的轨迹评价函数进行改进,并以全局路径提供子目标点引导DWA算法进行局部规划的方式完成算法融合。实验结果表明,融合算法相比于现有算法的总转向角度分别减少了45.6%、46.0%,验证了融合算法的有效性与可行性,并且相较于其他传统算法更具优越性。

关键词：路径规划水面船艇全局最优实时避障航行安全 A^(*)算法动态窗口法融合算法

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辐射冷却相变材料热管理性能实验研究

工程热物理学报 2024年第2期45卷 520-524页

作者：翟化天范德松于坤洋李志松李强南京理工大学电子设备热管理工信部重点实验室南京210094 中国人民解放军93126部队北京100084 上海卫星工程研究所上海201109

辐射冷却被认为是解决电子设备过热问题的创新被动方法。然而,较低的净冷却功率限制了其应用。本文提出了一种基于辐射冷却和相变效应的复合材料实现对产热器件的热缓冲。以三聚氰胺泡沫(MF)为三维骨架,聚乙二醇(PEG)为相变材料,含氟聚... 详细信息

辐射冷却被认为是解决电子设备过热问题的创新被动方法。然而,较低的净冷却功率限制了其应用。本文提出了一种基于辐射冷却和相变效应的复合材料实现对产热器件的热缓冲。以三聚氰胺泡沫(MF)为三维骨架,聚乙二醇(PEG)为相变材料,含氟聚合物(PVDF-HFP)为辐射冷却层,制备了具有优异抗泄露能力的辐射冷却相变材料(RC-PCMs)。复合材料不仅具有高太阳反射率(0.93)和高红外发射率(0.91),还具有高焓值(182 J/g)的特性。这项工作为新型被动辐射冷却技术提供了有益的参考。

关键词：辐射冷却相变材料热缓冲辐射特性

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基于机器学习的网络异常流量检测

安徽科技学院学报 2024年第1期38卷 111-116页

作者：沈徳松安徽文达信息工程学院安徽合肥231201

目的:探索基于XGBoost算法的网络异常流量检测方法,并评估其分类准确率。方法:根据X GBoost算法和主成分分析的技术原理,梳理了网络异常流量的类型、具体表现和异常流量的成因。采用136.4万条网络流量样本作为实验数据集,包括77个网络... 详细信息

目的:探索基于XGBoost算法的网络异常流量检测方法,并评估其分类准确率。方法:根据X GBoost算法和主成分分析的技术原理,梳理了网络异常流量的类型、具体表现和异常流量的成因。采用136.4万条网络流量样本作为实验数据集,包括77个网络流量特征和8种网络流量类型。进一步构建XGBoost分类模型,采用多个分类器,实现对网络异常流量的有效检测和识别。结果:XGBoost算法对网络异常流量的检测准确率达到了96.32%。结论:XGBoost算法在网络异常流量检测方面具有出色的性能和可靠性,能够有效为网络管理员提供有效的辅助决策和保护措施。

关键词：机器学习 XGBoost算法主成分分析网络异常流量

基于差分隐私模型的移动众包系统路径隐私研究

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黄山学院学报 2024年第3期26卷 23-26页

作者：沈德松安徽文达信息工程学院商贸学院安徽合肥231201

众包的概念自被提出以来,就引起了社会各界的关注。在大数据时代背景下智能控制的迅速发展也为众包任务的执行提供了有利条件。众包具有方便、快速、有效的优势,这必然成为许多学者的重点研究方向。然而为了避免出现一些安全隐患,在整... 详细信息

众包的概念自被提出以来,就引起了社会各界的关注。在大数据时代背景下智能控制的迅速发展也为众包任务的执行提供了有利条件。众包具有方便、快速、有效的优势,这必然成为许多学者的重点研究方向。然而为了避免出现一些安全隐患,在整个众包任务的执行过程中参与者想要尽可能地提供更少的个人信息,在确保隐私数据安全地同时能顺利地执行众包任务是设计众包机制首要考虑的问题。因此,对众包以及其工作流程、差分隐私的数学定义、实现机制进行阐述,再将差分隐私应用在不同众包场景下进行分析,最后将基于保序回归的差分隐私直方图构造算法应用到真实数据集上。通过对比分析发现此算法构造的直方图数据精度更高。

关键词：众包隐私保护差分隐私保序回归

Synthesized All-Pass Waveguide for Ultrafast Electronics

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Engineering 2023年第11期30卷 49-54页

作者： desong Wang Ke Wu Poly-Grames Research Center Department of Electrical EngineeringPolytechnique MontréalMontrealQC H3T 1J4Canada

Ultrashort pulse transmission has been recognized as a primary problem that fundamentally hinders the development of ultrafast electronics beyond the current nanosecond timescale.This requires a transmission line or waveguide that exhibits an all-pass frequency behavior for the transmitted ultrashort pulse signals.However,this type of waveguiding structure has not yet been practically developed;groundbreaking innovations and advances in signal transmission technology are urgently required to address this scenario.Herein,we present a synthesized all-pass waveguide that demonstrates record guidedwave controlling capabilities,including eigenmode reshaping,polarization rotation,loss reduction,and dispersion improvement.We experimentally developed two waveguides for use in ultrabroad frequency ranges(direct current(DC)-to-millimeter-wave and DC-to-terahertz).Our results suggest that the waveguides can efficiently transmit picosecond electrical pulses while maintaining signal integrity.This waveguide technology is an important breakthrough in the evolution of ultrafast electronics,providing a path towards frequency-engineered ultrashort pulses for low-loss and low-dispersion transmissions.

关键词： All-pass waveguide Ultrashort pulse Picosecond transmission Ultrafast electronics Terahertz technology Mode-selective transmission line

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水溶磷酸一铵副产渣生产含硫低氮高磷复合肥

磷肥与复肥 2024年第3期39卷 24-25页

作者：赵德松云南云天化云峰化工有限公司

随着水溶磷酸一铵装置产能增大，副产渣量增加，不仅积压库存较大，还会带来环境风险。通过市场调研和可行性探讨，使用副产渣作为原料开发一款较高适应性的含硫低氮高磷复合肥产品。介绍含硫低氮高磷复合肥的生产工艺流程、试生产情况... 详细信息

随着水溶磷酸一铵装置产能增大，副产渣量增加，不仅积压库存较大，还会带来环境风险。通过市场调研和可行性探讨，使用副产渣作为原料开发一款较高适应性的含硫低氮高磷复合肥产品。介绍含硫低氮高磷复合肥的生产工艺流程、试生产情况、生产技术优化。该产品的开发既解决了制约水溶磷酸一铵产能提升的渣的利用问题，又推动了产品结构调整，拓展了市场，创造出更好的品牌价值。

关键词：水溶磷酸一铵副产渣含硫低氮高磷复合肥