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Journal of Pharmaceutical Analysis 2022年第2期12卷 293-300页

作者： Xue Xiao Kaili He ya-jun hou Zhangmin Xiang Yunyun yang Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology Guangdong Provincial Engineering Research Center for Ambient Mass SpectrometryInstitute of AnalysisGuangdong Academy of Sciences(China National Analytical CenterGuangzhou)Guangzhou510070China

A rapid and sensitive method for analyzing trace b-blockers in complex biological samples,which involved magnetic solid-phase extraction(MSPE)coupled with Fourier transform ion cyclotron resonance mass spectrometry(FTICR-MS),was *** nanosilver-functionalized magnetic nanoparticles with an interlayer of poly(3,4-dihydroxyphenylalanine)(polyDOPA@Ag-MNPs)were synthesized and used as MSPE adsorbents to extract trace b-blockers from biological *** extraction,the analytes loaded on the polyDOPA@Ag-MNPs were desorbed using an organic solvent and analyzed by *** method was rapid and sensitive,with a total detection procedure of less than 10 min as well as limits of detection and quantification in the ranges of 3.5-6.8 pg/mL and 11.7-22.8 pg/mL,*** accuracy of the method was also desirable,with recoveries ranging from 80.9%to 91.0%following the detection of analytes in human blood *** the experimental results demonstrated that the developed MSPE-FTICR-MS method was suitable for the rapid and sensitive analysis of trace b-blockers in complex biological samples.

关键词： β-blockers Magnetic solid-phase extraction Nanosilver-functionalized magnetic nanoparticles Poly(3,4-dihydroxyphenylalanine) Fourier transform ion cyclotron resonance mass spectrometry

Selenocysteine antagonizes oxygen glucose deprivation-induced damage to hippocampal neurons

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Neural Regeneration Research 2018年第8期13卷 1433-1439页

作者： Xian-jun Wang Mei-Hong Wang Xiao-Ting Fu ya-jun hou Wang Chen Da-Chen Tian Su-Yun Bai Xiao-yan Fu Department of Neurology People's Hospital of Linyi Linyi Shandong Province China Department of Neurology People's Hospital of Yishui Linyi Shandong Province China School of Basic Medicine Taishan Medical University Taian Shandong Province China

Designing and/or searching for novel antioxidants against oxygen glucose effective strategy for the treatment of human isdlemic stroke. Selenium is deprivation （OGD）-induced oxidative damage represents an an essential trace dement, which is beneficial in the chemo- prevention and chemotherapy of cerebral ischemic stroke. The underlying mechanisms for its therapeutic effects, however, are not well documented. Selenocysteine （SeC） is a selenium-containing amino acid with neuroprotective potential. Studies have shown that SeC can reduce irradiation-induced DNA apoptosis by reducing DNA damage. In this study, the in vitro protective potential and mechanism of action of SeC against OGD-induced apoptosis and neurotoxicity were evaluated in HT22 mouse hippocampal neurons. We cultured HT22 cells in a glucose-free medium containing 2 mM Na2S402, which formed an OGD environment, for 90 minutes. Findings from MTT, flow cytometry and TUNEL staining showed obvious cytotoxicity and apoptosis in HT22 cells in the OGD condition. The activation of Caspa se-7 and Caspase-9 further revealed that OGD-induced apoptosis of HT22 cells was mainly achieved by triggering a mitochondrial-medi- ated pathway. Moreover, the OGD condition also induced serious DNA damage through the accumulation of reactive oxygen species and superoxide anions. However, SeC pre-treatment for 6 hours effectively inhibited OGD-induced cytotoxicity and apoptosis in HT22 cells by inhibiting reactive oxygen species-mediated oxidative damage. Our findings provide evidence that SeC has the potential to suppress OGD-induced oxidative damage and apoptosis in hippocampal neurons.

关键词： selenium selenocysteine ischemic stroke oxygen glucose deprivation hippocampal neuron mitochondria reaction oxygen species superoxide anion oxidative damage apoptosis

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高超声速飞行器轨迹跟踪控制仿真

计算机仿真 2018年第10期35卷 72-77页

作者：李雅君侯明善梁帅刘柏均西北工业大学陕西西安710129

对于具有严重非线性、多变量以及参数不确定等特点的高超声速飞行器的轨迹控制系统,滑模控制是一种十分有效的控制方法,但传统的滑模控制会不可避免的产生抖振现象,为了彻底消除这一现象,设计了一种新型的自适应全阶终端无抖振滑模控制... 详细信息

对于具有严重非线性、多变量以及参数不确定等特点的高超声速飞行器的轨迹控制系统,滑模控制是一种十分有效的控制方法,但传统的滑模控制会不可避免的产生抖振现象,为了彻底消除这一现象,设计了一种新型的自适应全阶终端无抖振滑模控制律。首先,简要介绍了高超声速飞行器纵向非线性模型,并给出反馈线性化后速度和高度的状态方程。其次,假设所有状态可测,采用全阶终端滑模滑动流型,分别对速度和高度两个子系统设计有限时间收敛的全阶终端滑模控制器,以避免奇异问题,并引入一阶低通滤波器作用于控制输入,以消除由开关函数引起的抖振现象;最后,采用扩张状态观测器对不可测状态进行估计,设计了自适应全阶终端滑模控制律。数字仿真表明,自适应全阶滑模控制器能够使系统在有限时间内跟踪到给定指令,并彻底消除了抖振现象。仿真验证了所提出控制律的有效性。

关键词：高超声速飞行器无抖振滑模控制扩张状态观测器

Activin A receptor type 1C single nucleotide polymorphisms associated with esophageal squamous cell carcinoma risk in Chinese population

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 39-51页

作者： Si-Yun Lin hou Huang Jin-Jie Yu Feng Su Tian Jiang Shao-Yuan Zhang Lu Lv Tao Long Hui-Wen Pan jun-Qing Qi Qiang Zhou Wei-Feng Tang Guo-Wen Ding Li-Ming Wang Li-Jie Tan jun Yin Department of Thoracic Surgery Zhongshan Hospital Affiliated to Fudan UniversityShanghai 200032China Shanghai Key Laboratory of Clinical Geriatric Medicine Huadong Hospital Affiliated to Fudan UniversityShanghai 200040China Department of Cardiothoracic Surgery The Affiliated People's Hospital of Jiangsu UniversityZhenjiang 212002Jiangsu ProvinceChina Department of Thoracic Surgery Sichuan Cancer Hospital&InstituteChengdu 610042Sichuan ProvinceChina Department of Cardiothoracic Surgery Nanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210000Jiangsu ProvinceChina Department of Respiratory and Critical Care Medicine Shanghai Xuhui Central HospitalShanghai 200032China

BACKGROUND Transforming growth factor-β(TGF-β)superfamily plays an important role in tumor progression and *** A receptor type 1C(ACVR1C)is a TGF-βtype I receptor that is involved in tumorigenesis through binding to dif-ferent *** To evaluate the correlation between single nucleotide polymorphisms(SNPs)of ACVR1C and susceptibility to esophageal squamous cell carcinoma(ESCC)in Chinese Han *** In this hospital-based cohort study,1043 ESCC patients and 1143 healthy controls were *** SNPs(rs4664229,rs4556933,rs77886248,rs77263459,rs6734630)of ACVR1C were assessed by the ligation detection reaction ***-Weinberg equilibrium test,genetic model analysis,stratified analysis,linkage disequi-librium test,and haplotype analysis were *** Participants carrying ACVR1C rs4556933 GA mutant had significantly decreased risk of ESCC,and those with rs77886248 TA mutant were related with higher risk,especially in older male *** the haplotype analysis,ACVR1C Trs4664229Ars4556933Trs77886248Crs77263459Ars6734630 increased risk of ESCC,while Trs4664229Grs4556933Trs77886248Crs77263459Ars6734630 was associated with lower susceptibility to *** ACVR1C rs4556933 and rs77886248 SNPs were associated with the susceptibility to ESCC,which could provide a potential target for early diagnosis and treatment of ESCC in Chinese Han population.

关键词： Activin A receptor type 1C Single nucleotide polymorphisms Esophageal squamous cell carcinoma Genetic susceptibility Hospital-based cohort study

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土壤冻融过程中的水热参数化方案研究进展

高原气象 2025年第1期44卷 1-15页

作者：侯雅李伟平左金清中国气象科学研究院灾害天气国家重点实验室北京100081 中国气象局地球系统数值预报中心北京100081 中国气象局气候预测研究重点开放实验室/国家气候中心北京100081

冻土是陆地冰冻圈的重要组成部分,其冻融循环变化能够影响土壤结构、土壤水热传输以及土壤生物化学等过程,并通过陆-气相互作用影响局地甚至全球天气气候。因此,研究土壤冻融过程对冻土区人类生产生活和了解区域外天气气候变化具有重要... 详细信息

冻土是陆地冰冻圈的重要组成部分,其冻融循环变化能够影响土壤结构、土壤水热传输以及土壤生物化学等过程,并通过陆-气相互作用影响局地甚至全球天气气候。因此,研究土壤冻融过程对冻土区人类生产生活和了解区域外天气气候变化具有重要的科学意义。本文回顾了土壤中的砾石、有机质对土壤冻融过程的影响及物理机制,总结了土壤冻融过程中水热参数化的相关研究成果,包括土壤导热率和水力学参数的计算、水热耦合方案以及冻融锋面计算方案等。相对于普通的矿物质土粒而言,砾石具有高导热率和低热容,有机质具有低导热率和高热容,他们对热量在土壤中的传输及土壤温度垂直分布有不同的影响。另外,砾石和有机质的存在改变了土壤孔隙度、土壤基质毛细作用与吸附作用,进而影响水分在土壤中的传输过程和垂直分布。已有研究表明:(1)当前大部分数值模式中土壤导热率采用Johansen方案及其派生方案进行计算,其中Balland-Arp方案考虑了砾石和有机质对土壤导热率的影响,该方案更好地刻画了土壤冻融过程中土壤导热率变化的连续性;综合考虑热-水-变形相互作用的导热率参数化方案可以较好地刻画土壤冻融过程中的水热耦合和土体冻胀的作用,对相变过程中土壤导热率变化特征的模拟更符合实际观测。(2)过冷水参数化方案刻画了土壤液态水在0℃以下存在的事实;相变温度方案描述了土壤相变温度低于0℃且不固定的事实;导水阻抗方案考虑了土壤冻结对土壤水分下渗的阻抗作用,改善了对冻土区水文过程的模拟效果。(3)土壤冻融过程伴随着水分的相变和能量的转化,水热耦合方案的发展能够较好地刻画土壤中热力-水文过程的协同变化特征,细化了对冻融过程中水分和能量相互作用的复杂物理机制的描述。(4)等温框架的数值模式通过模拟每层土壤中间深度的冻融过程代表该模式分层的整体特征,导致对冻融深度的严重高估或低估,尤其是对厚度较大的模式深层土壤,冻融锋面计算方案的提出和应用减小了这种模拟偏差。目前土壤冻融参数化方案的不足之处包括:绝大多数数值模式没有考虑土壤盐分导致土壤水的冰点降低这一事实;虽然大部分数值模式考虑了土壤有机质对土壤水、热传输的影响,但是模式中对土壤有机质含量及垂直分布的考虑与植被根系的生长状态脱节;模式模拟的土壤深度不足并且下边界通量为零的假定不符合实际情况。发展土壤溶质传输参数化方案以模拟盐分的分布、刻画植被根系生长过程和土壤有机质的分布特征、考虑深层土壤对浅层的热力学影响并完善数值模式中的下边界条件,这些是未来陆面模式改进土壤冻融过程模拟的可能方向。

关键词：土壤冻融过程参数化方案土壤导热率土壤水文参数冻融锋水热耦合

四波混频Autler-Townes分裂中的探测光影响

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原子与分子物理学报 2025年第3期42卷 110-115页

作者：裴丽娅侯海龙北京化工大学数理学院北京100029

在双Λ-型四波混频系统中,研究了探测光强度对Autler-Townes(AT)分裂效应的影响.随着弱探测光强度增大,由缀饰态共振产生的AT分裂双峰间隔不变,但却逐渐增宽线宽且减弱直至消失;而在强耦合光失谐条件下,不对称地位于单光子共振峰两侧的A... 详细信息

在双Λ-型四波混频系统中,研究了探测光强度对Autler-Townes(AT)分裂效应的影响.随着弱探测光强度增大,由缀饰态共振产生的AT分裂双峰间隔不变,但却逐渐增宽线宽且减弱直至消失;而在强耦合光失谐条件下,不对称地位于单光子共振峰两侧的AT分裂双峰却会逐渐趋于对称分布.详细讨论了探测光场对原子的缀饰影响,提出通过探测光强度可以调控原子两基态之间的有效Raman相干,从而影响AT分裂双峰的特征.

关键词：四波混频原子相干 Autler-Townes分裂缀饰态横向弛豫率

Low-temperature chlorination roasting technology for the simultaneous recovery of valuable metals from spent LiCoO_(2)cathode material

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 80-91页

作者： junjie Shi Changle hou Jingjing Dong Dong Chen Jianzhong Li Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

With the continuous increase in the disposal volume of spent lithium-ion batteries(LIBs),properly recycling spent LIBs has become essential for the advancement of the circular *** study presents a systematic analysis of the chlorination roasting kinetics and proposes a new two-step chlorination roasting process that integrates thermodynamics for the recycling of LIB cathode *** activation energy for the chloride reaction was 88.41 kJ/mol according to thermogravimetric analysis–derivative thermogravimetry data obtained by using model-free,model-fitting,and Z(α)function(αis conversion rate).Results indicated that the reaction was dominated by the first-order(F1)model when the conversion rate was less than or equal to 0.5 and shifted to the second-order(F2)model when the conversion rate exceeded *** conditions were determined by thoroughly investigating the effects of roasting temperature,roasting time,and the mass ratio of NH_(4)Cl to LiCoO_(2).Under the optimal conditions,namely 400℃,20 min,and NH_(4)Cl/LiCoO_(2)mass ratio of 3:1,the leaching efficiency of Li and Co reached 99.43% and 99.05%,*** of the roasted products revealed that valuable metals in LiCoO_(2)transformed into CoCl_(2) and ***,the reaction mechanism was elucidated,providing insights for the establishment of a novel low-temperature chlorination roasting technology based on a crystal structure *** technology can guide the development of LIB recycling processes with low energy consumption,low secondary pollution,high recovery efficiency,and high added value.

关键词： spent lithium-ion battery thermodynamics chlorination roasting kinetics circular economy

Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： Yong hou Shuo Zhang Jie Dang Jia Guo Hanghang Zhou Xuewei Lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

Investigating Ion Transport through Artificial Transmembrane Channels Containing Introverted Groups

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Chinese Journal of Chemistry 2022年第11期40卷 1293-1297页

作者： ya-Wei Li Yong-Hong Fu jun-Li hou Department of Chemistry Fudan University220 Handan RoadShanghai 200433China

The investigation on the relationship between structure and transport activity of artificial transmembrane channels has still re-mained a challenge because of lacking strategy to precisely arrange the functional group in the channel ***,we report a general strategy to monitor ion transport through the artificial channels by using unimolecular tubular molecules containing intro-verted *** found that the ion transport rate decreased with elongation of the introverted sidechains and the channel with propyl group as the introverted sidechain exhibited the longest opening duration ***,we have revealed that,comparing to the ion transport rate,the opening duration is a more important factor for determining the transport activity of the artificial channels.

关键词： Supramolecular chemistry Self-assembly Nanostructures Artificial transmembrane channels Pillararene

Packet Tracer软件在计算机网络实验教学中的应用

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实验科学与技术 2011年第6期9卷 30-33页

作者：姜恩华张亚萍侯俊钦淮北师范大学物理与电子信息学院安徽淮北235000

文章以计算机网络理论教学内容为基础,总结了计算机网络实验教学内容和要求,借助Packet Tracer软件完成计算机网络实验教学,由计算机、网卡、交换机和路由器构成计算机网络,通过对网络的配置介绍了仿真实验过程,学生通过完成仿真实验,... 详细信息

文章以计算机网络理论教学内容为基础,总结了计算机网络实验教学内容和要求,借助Packet Tracer软件完成计算机网络实验教学,由计算机、网卡、交换机和路由器构成计算机网络,通过对网络的配置介绍了仿真实验过程,学生通过完成仿真实验,培养组建、使用和管理计算机网络的技能,加深学生对计算机网络理论和概念的掌握和理解,达到通过实验教学促进理论教学的目的。

关键词： Packet Tracer软件计算机网络实验教学