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Chinese Chemical Letters 2024年第4期35卷 481-485页

作者： Qiongqiong Wan Yanan Xiao Guifang Feng Xin Dong Wenjing Nie Ming Gao Qingtao Meng suming chen The Institute for Advanced Studies Renmin Hospital of Wuhan UniversityWuhan UniversityWuhan 430072China

There is a close relationship between the biological functions of lipids and their structures, and various isomers greatly increases the complexity of lipid structures. The C=C bond location and sn-position are two of the essential attributes that determine the structures of unsaturated lipids. However, simultaneous identification of both attributes remains challenging. Here, we develop a visible-light-activated aziridination reaction system, which enables the dual-resolving of the C=C bond location and sn-position isomerism of in lipids when combines with liquid chromatography-mass spectrometry(LC-MS). Based on the derivatization of C=C bonds with Ph I=NTs, their location in lipids could be easily identified by tandem MS. Especially, the sn-position isomers of unsaturated phosphatidylcholine(PC) can be separated and quantified by LC-MS after the derivatization. By using the proposed method, the significant changes of the sn-position isomers ratios of PC in mouse brain ischemia were revealed. This study offers a powerful tool for deep lipid structural biology.

关键词： Aziridination Lipid isomers C=C bond location sn-Position Mass spectrometry

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钢铁镀镉零件黑斑原因探析及改进

包装工程 2024年第15期45卷 307-312页

作者：盛永清王浩军陈素明中航西安飞机工业集团股份有限公司西安710089

目的针对夏季多雨季节,飞机支座和螺栓等钢铁镀镉零件在周转/装配期间表面易出现黑斑现象,通过镀镉层表面成分分析定位产生原因并制定改进措施。方法通过镀镉层黑斑和正常区宏观形貌观察、扫描电镜及能谱分析表面成分;通过控制电镀镉前... 详细信息

目的针对夏季多雨季节,飞机支座和螺栓等钢铁镀镉零件在周转/装配期间表面易出现黑斑现象,通过镀镉层表面成分分析定位产生原因并制定改进措施。方法通过镀镉层黑斑和正常区宏观形貌观察、扫描电镜及能谱分析表面成分;通过控制电镀镉前处理及铬酸盐钝化、临时防护等耐湿热腐蚀对比试验,验证改进措施有效性。结果通过表面能谱成分分析,黑斑区域无Cr确定了镀镉铬酸盐钝化膜不连续、Al元素含量异常确定了前处理吹砂介质残留致使镉层不连续;通过电镀镉钝化和未钝化状态的耐湿热腐蚀、涂敷F-35防锈油试验验证,确定彻底清理前处理吹砂介质残留、电镀镉铬酸盐钝化膜老化等改进措施可保证镀镉层及钝化膜完整,F-35防锈油临时防护可有效提高镀镉层耐蚀性。结论镀前预处理、镀镉及后处理过程控制对镀镉层质量起决定性作用,零件制造周转有效防护对镀层完整性持续保持至关重要,防锈油等临时防护可有效提高镀层的防护性能。

关键词：镀镉钝化黑斑

硫酸阳极氧化对7A65航空铝合金疲劳性能的影响

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电镀与涂饰 2024年第2期43卷 18-26页

作者：吕弛张锰岳珊陈素明中航西安飞机工业集团股份有限公司陕西西安710089

[目的]铝合金零件的疲劳性能是决定飞机服役寿命的关键因素。硫酸阳极氧化是铝合金零件常用的表面处理工艺,研究其对铝合金疲劳性能的影响对指导生产极其重要。[方法]针对新型航空铝合金7A65,采用重复退膜-阳极氧化的方式开展实验。通... 详细信息

[目的]铝合金零件的疲劳性能是决定飞机服役寿命的关键因素。硫酸阳极氧化是铝合金零件常用的表面处理工艺,研究其对铝合金疲劳性能的影响对指导生产极其重要。[方法]针对新型航空铝合金7A65,采用重复退膜-阳极氧化的方式开展实验。通过疲劳试验机对试样进行疲劳性能测试,绘制应力-疲劳寿命曲线,分析和对比重复退膜和阳极氧化不同次数后7A65铝合金的疲劳性能。通过体视显微镜和扫描电子显微镜对典型断口形貌进行分析,并探讨了其疲劳失效机制。[结果]7A65铝合金在重复退膜-阳极氧化处理后疲劳极限明显下降。经过2次阳极氧化,7A65铝合金的疲劳极限下降为原疲劳极限的61.1%;继续进行退膜-阳极氧化处理,疲劳极限下降趋缓,4次阳极氧化后的疲劳极限为原疲劳极限的56.5%。在此过程中,其疲劳断口呈现出由单一裂纹源向多裂纹源,以及从韧性断裂向脆性断裂的转变。[结论]硫酸阳极氧化对7A65铝合金疲劳性能的影响较大,在生产中应当控制阳极氧化零件的返修次数。

关键词：铝合金航空硫酸阳极氧化疲劳性能断口形貌

航空耐候阻燃水性丙烯酸聚氨酯涂料的制备及应用

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电镀与涂饰 2024年第10期43卷 108-115页

作者：王瑞欣王红妮陈素明胡生双中国航空制造技术研究院北京100024 中航西安飞机工业集团股份有限公司陕西西安710089

[目的]开展水性丙烯酸聚氨酯树脂结构设计和聚合条件的研究,合成出性能优良的氟改性丙烯酸聚氨酯乳液,并以此为主体树脂,开发一款耐候、阻燃的水性涂料。[方法]讨论了树脂和固化剂种类、异氰酸酯基/羟基当量比、颜基比及阻燃剂对涂料性... 详细信息

[目的]开展水性丙烯酸聚氨酯树脂结构设计和聚合条件的研究,合成出性能优良的氟改性丙烯酸聚氨酯乳液,并以此为主体树脂,开发一款耐候、阻燃的水性涂料。[方法]讨论了树脂和固化剂种类、异氰酸酯基/羟基当量比、颜基比及阻燃剂对涂料性能的影响。[结果]在优化条件下制备的水性丙烯酸聚氨酯涂料具有优良的综合性能,涂膜在1000 h紫外老化试验后的色差为1.2,满足运输类飞机适航标准(CCAR-25)对阻燃的要求,其耐水性、耐油性、耐冲击性及附着力均达到了传统溶剂型涂料的水平。[结论]该涂料可应用于飞机内部涂装。

关键词：水性丙烯酸树脂聚氨酯航空涂料耐候阻燃

Analysis of local structure of Arg10 domain in apo-α- lactalbumin with a polarity-sensitive arginine-specific fluorescent probe

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Science China Chemistry 2009年第6期52卷 809-814页

作者： WANG ShuJuan chen suming MA HuiMin Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing 100190China

The polarity-sensitive fluorescent probe, 3-(4-chloro-6-p-glyoxalphenoxy-1,3,5-triazinylamino)-7- (dimethylamino)-2-methylphenazine, was used to analyze the local structure of apo-α-lactalbumin by detecting the polarity and conformational changes of the arginine residue (Arg10) domain. The polarity of the Arg10 domain in both native and heat-denatured apo-α-lactalbumin was determined, which corresponds to a dielectric constant of 16, and the hydrophobic core near the Arg10 was found to be conservative for heating. Meanwhile, the effect of Ca2+ binding on the conformational changes of the Arg10 domain was studied, revealing that the hydrophobic core near the Arg10 is insensitive to the binding of Ca2+.

关键词： arginine-specific labeling fluorescent probes local polarity detection conformational changes Ca2+ binding

Uncovering growth species of multivariate MOFs in liquid phase by mass spectrometry

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Chinese Chemical Letters 2022年第8期33卷 3993-3998页

作者： Jinli Han suming chen Xiaochun Zhou Hexiang Deng Key Laboratory of Biomedical Polymers-Ministry of Education College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China Division of Advanced Nanomaterials Suzhou Institute of Nano-tech and Nano-bionicsChinese Academy of SciencesSuzhou 215125China The Institute for Advanced Studies Wuhan UniversityWuhan 430072China

The unveiling of MOF growth mechanism is hampered by the lack of fundamental knowledge about the very early stage of nucleation,especially the form and ratio of molecular species in the solution for crystal ***,we report the detection of growth species for a series of MOFs with mono-linker,CuMOF-2-BDC and Cu-MOF-2-NDC,and two linkers,MTV-MOF-2-(C_(4)H_(4))x,by high resolution ESI-MS,where a large variety of Cu-containing species are identified *** solvent molecules such as H_(2)O,methanol and DMF participate in the formation of these species,other than ***,in the growth solution of MTV-MOF-2-(C_(4)H_(4))x,growth species containing two different organic linkers are *** feeding ratio is not the only factor controlling the distribution of growth species for MTVMOFs,but also the solvent involves in coordination,an aspect usually overlooked previously.

关键词： Metal-organic framework Multivariate MOFs Mass spectrometry Growth species Self-assembly

时效温度对TB18钛合金组织和力学性能的影响

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金属热处理 2024年第2期49卷 190-195页

作者：胡生双陈素明颜家维岳珊高晓颖欧阳德来中航西安飞机工业集团股份有限公司陕西西安710089 南昌航空大学材料科学与工程学院江西南昌330063

利用拉伸试验机、光学显微镜和扫描电镜等手段研究了不同时效温度对TB18钛合金力学性能和组织的影响。结果表明,随着时效温度升高,TB18钛合金抗拉强度和屈服强度不断降低,伸长率和断面收缩率提高。从强度和塑性综合考虑,当时效温度为53... 详细信息

利用拉伸试验机、光学显微镜和扫描电镜等手段研究了不同时效温度对TB18钛合金力学性能和组织的影响。结果表明,随着时效温度升高,TB18钛合金抗拉强度和屈服强度不断降低,伸长率和断面收缩率提高。从强度和塑性综合考虑,当时效温度为530℃时,TB18钛合金的综合力学性能最好。此时抗拉强度为1285.5 MPa,屈服强度为1206 MPa,伸长率为7.8%,断面收缩率为16%。TB18钛合金锻态是典型的等轴组织,经870℃×2 h,空冷固溶处理后为等轴β晶粒,晶粒尺寸为200~250μm。TB18钛合金经不同温度时效后,次生α相的微观形貌相似,均为片层状。随着时效温度的升高,合金内部析出的次生α相片层尺寸呈增大趋势。

关键词： TB18钛合金时效温度力学性能组织

A capacitive sensor based on molecularly imprinted polymers and poly(p-aminobenzene sulfonic acid) film for detection of pazufloxacin mesilate

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Science China Chemistry 2007年第4期50卷 547-553页

作者： ZHOU Lu YE GuangRong YUAN Ruo CHAI YaQin chen suming College of Chemistry and Chemical Engineering Southwest UniversityChongqing 400715China

A novel capacitive sensor for pazufloxacin mesilate (pazufloxacin) determination was developed by electropolymerizing p-aminobenzene sulfonic (p-ABSA) and molecularly imprinted polymers (MPs), which was synthesized through thermal radical copolymerization of metharylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) in the presence of pazufloxacin template molecules, on the gold electrode surface. Furthermore, 1-dedecanethiol was used to insulate the modified electrode. Alternating current (ac) impedance experiments were carried out with a Model IM6e to obtain the capacitance responses. Under the optimum conditions, the sensor showed linear capacitance response to pazufloxacin in the range of 5 ng·mL?1 to 5 μg·mL?1 with a relative standard deviation (RSD) 5.3% (n=7) and a detection limit of 1.8 ng·mL?1. The recoveries for different concentration levels of pazufloxacin samples varied from 94.0% to 102.0%. Electrochemical experiments indicated the capacitive sensor exhibited good sensitivity and selectivity and showed excellent parameters of regeneration and stability.

关键词： capacitive sensor molecularly imprinted polymers p-aminobenzene sulfonic acid pazufloxacin mesilate

PH13-8Mo不锈钢带状偏析及其在热处理中的演变

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金属热处理 2024年第7期49卷 152-157页

作者：陈素明岳珊胡生双赵虎李毅吴海峰欧阳德来中航西安飞机工业集团股份有限公司陕西西安710089 南昌航空大学材料科学与工程学院江西南昌330063

以某PH13-8Mo不锈钢轴零件为研究对象,研究了PH13-8Mo不锈钢带状偏析组织特征及其在固溶时效处理中的演变。结果表明,PH13-8Mo不锈钢中存在成分偏析带和δ铁素体偏析带两种类型带状偏析,成分偏析带呈平直连续状分布,δ铁素体偏析带呈平... 详细信息

以某PH13-8Mo不锈钢轴零件为研究对象,研究了PH13-8Mo不锈钢带状偏析组织特征及其在固溶时效处理中的演变。结果表明,PH13-8Mo不锈钢中存在成分偏析带和δ铁素体偏析带两种类型带状偏析,成分偏析带呈平直连续状分布,δ铁素体偏析带呈平直不连续状分布。成分偏析带中Ni元素正偏析、Fe元素负偏析,Ni、Fe含量分别为11%和72%,分别低于和高于钢中Ni、Fe元素含量。δ铁素体偏析带中Ni、Fe含量分别为4%和71%,均低于钢中Ni、Fe平均含量;Cr、Mo、Al含量分别为17%、4.5%和1.84%,均高于钢中Cr、Mo、Al平均含量。1100℃×2 h固溶+540℃×4 h时效可有效消除PH13-8Mo不锈钢成分偏析带,但对δ铁素体偏析带消除作用影响不明显。

关键词： PH13-8Mo不锈钢带状偏析固溶时效

Compact ultrafast neutron sources via bulk acceleration of deuteron ions in an optical trap

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Matter and Radiation at Extremes 2024年第5期9卷 22-31页

作者： Zhiyu Lei Hanghang Ma Xiaobo Zhang Lin Yu Yihang Zhang Yutong Li suming Weng Min chen Jie Zhang Zhengming Sheng Key Laboratory for Laser Plasmas and School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Centre of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 201210China College of Physics and Electronics Engineering Northwest Normal UniversityLanzhou 730070China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

A scheme for a quasi-monoenergetic high-flux neutron source with femtosecond duration and highly anisotropic angular distribution is *** scheme is based on bulk acceleration of deuteron ions in an optical trap or density grating formed by two counter-propagating laser pulses at an intensity of-10^(16)W~cm^(2)in a near-critical-density *** deuterons are first pre-accelerated to an energy of tens of keV in the ambipolar fields formed in the optical *** energy is boosted to the MeV level by another one or two laser pulses at an intensity of-10^(20)W~cm^(2),enabling fusion reactions to be triggered with high *** contrast to previously proposed pitcher–catcher configurations,our scheme can provide spatially periodic acceleration structures and effective collisions between deuterons inside the whole target ***,neutrons are generated directly inside the optical *** simulations show that neutron pulses with energy 2–8 MeV,yield 10^(18)–10^(19)n/s,and total number 106–107 in a duration-400 fs can be obtained with a 25μm ***,the neutron pulses exhibit unique angularly dependent energy spectra and flux distributions,predominantly along the axis of the energy-boosting *** microsize femtosecond neutron pulses may find many applications,such as high-resolution fast neutron imaging and nuclear physics research.

关键词： acceleration scheme angular