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Interface properties and electronic structures of aromatic molecules with anhydride and thio-functional groups on Ag(111) and Au(111) substrates

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Chinese Physics B 2019年第10期28卷 286-291页

作者： wei-qi Yu Hong-Jun Xiao Ge-Ming Wang Wuhan Institute of Technology Wuhan 430205China National Center for Nanoscience and Technology Beijing 100190China

First-principles calculations for several aromatic molecules with anhydride and thio groups on Ag(111) and Au(111)reveal that the self-assembly structures and the interface properties are mainly determined by the functional groups of aromatic molecules. Detailed investigations of the electronic structures show that the electrons in molecular backbone are redistributed and charge transfer occurs through the bond between the metal and the functional groups after these molecules have been deposited on a metal substrate. The interaction between Ag(111)(or Au(111)) and aromatic molecules with anhydride functional groups strengthens the π bonds in the molecular backbone, while that between Ag(111)(or Au(111))and aromatic molecules with sulfur weakens the π bonds. However, the intrinsic electronic structures of the molecules are mostly conserved. The large-sized aromatic backbone has less influence on the nature of electronic structures than the small-sized one, either at the interface or at the molecules. These results are useful to build the good metal-molecule contact in molecule-based devices.

关键词： aromatic molecules electronic structures metal surface density functional theory

Experimental Investigation on Performance of Pulse Detonation Rocket Engine Model

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Chinese Journal of Aeronautics 2007年第1期20卷 9-14页

作者： LI qiang FAN wei YAN Chuan-jun HU Cheng-qi YE Bin School of Engine and Energy Northwestern Polytechnical University Xi＇an 710072 China

The PDRE test model used in these experiments utilized kerosene as the fuel, oxygen as oxidizer, and nitrogen as purge gas. The solenoid valves were employed to control intermittent supplies of kerosene, oxygen and purge gas. PDRE test model was 50 mm in inner diameter by 1.2 m long. The DDT （deflagration to detonation transition） enhancement device Shchelkin spiral was used in the test model. The effects of detonation frequency on its time-averaged thrust and specific impulse were experimentally investigated. The obtained results showes that the time-averaged thrust of PDRE test model was approximately proportional to the detonation frequency. For the detonation frequency 20 Hz, the time-averaged thrust was around 107 N, and the specific impulse was around 125 s. The nozzle experiments were conducted using PDRE test model with three traditional nozzles. The experimental results obtained demonstrated that all of those nozzles could augment the thrust and specific impulse. Among those three nozzles, the convergent nozzle had the largest increased augmentation, which was approximately 18%, under the specific condition of the experiment.

关键词： pulse detonation rocket engine impulse nozzle experimental investigation

不同包装和贮藏温度的澳洲坚果果仁贮藏品质及货架期预测

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食品科学 2024年第16期45卷 232-243页

作者：徐文婷付镓榕马尚玄魏元苗杨悦雪黄克昌郭刚军贺熙勇云南省热带作物科学研究所云南省澳洲坚果农业工程研究中心云南景洪666100

测定普通包装、真空包装、真空脱氧包装、氮气包装和氮气脱氧包装5种包装方式澳洲坚果果仁不同贮藏温度(4℃、常温、60℃)下水分含量、酸价、过氧化值及抗氧化活性等指标的变化,同时通过过氧化值建立动力学模型以预测澳洲坚果果仁的货... 详细信息

测定普通包装、真空包装、真空脱氧包装、氮气包装和氮气脱氧包装5种包装方式澳洲坚果果仁不同贮藏温度(4℃、常温、60℃)下水分含量、酸价、过氧化值及抗氧化活性等指标的变化,同时通过过氧化值建立动力学模型以预测澳洲坚果果仁的货架期。结果表明:采用氮气及氮气脱氧包装可显著降低生干果仁贮藏过程中酸价和过氧化值的增加幅度,减轻脂肪氧化酸败,减缓总酚含量的下降,维持较高的1,1-二苯基-2-三硝基苯肼自由基、2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)阳离子自由基及羟自由基清除能力;过氧化值与贮藏温度和贮藏时间均呈显著正相关(P<0.05),其变化规律符合一级动力学模型,Arrhenius方程具有较好的拟合性,货架期预测模型误差小于14%,氮气包装的货架期最长,在4℃、常温和60℃下的实测值分别为215、180、108 d,其次是氮气脱氧包装,实测值分别为205、175、104 d。

关键词：澳洲坚果包装处理贮藏品质抗氧化活性货架期预测模型

Nanoporous MoO_(3−x)/BiVO_(4)photoanodes promoting charge separation for efficient photoelectrochemical water splitting

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Nano Research 2022年第8期15卷 7026-7033页

作者： Songcan Wang Boyan Liu Xin Wang Yingjuan Zhang wei huang Frontiers Science Center for Flexible Electronics Xi’an Institute of Flexible Electronics(IFE)Xi’an Institute of Biomedical Materials&EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

Owing to the relatively short hole diffusion length,severe charge recombination in the bulk of bismuth vanadate(BiVO_(4))is the key issue for photoelectrochemical water ***,we design a nanoporous MoO_(3−x)/BiVO_(4)heterojunction photoanode to promote charge *** efficient electron transport properties of oxygen deficient MoO_(3−x)and the nanoporous structure are beneficial for charge separation,leading to a significantly enhanced PEC *** optimized MoO_(3−x)/BiVO_(4)heterojunction photoanode exhibits a photocurrent density of 5.07 mA·cm^(−2)for Na_(2)SO_(3)*** depositing FeOOH/NiOOH dual oxygen evolution cocatalysts to promote surface kinetics,a high photocurrent density of 4.81 mA·cm^(−2)can be achieved for PEC water splitting,exhibiting an excellent applied bias photon-to-current efficiency of 1.57%.Moreover,stable overall water splitting is achieved under consecutive light illumination for 10 *** provide a proof of concept for the design of efficient BiVO_(4)-based heterojunction photoanodes for stable PEC water splitting.

关键词： water splitting bismuth vanadate heterojunction oxygen vacancies charge separation

基于系统工程的海外油田终端处理厂管理体系研究

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化工管理 2024年第27期 8-11页

作者：魏可可杨月明李琦中海油安全技术服务有限公司

文章探讨了海外油田开发中终端处理厂管理的挑战与应对策略，特别是在油田增产上产工程建设期，终端处理厂面临复杂生产作业态势和高风险环境，亟需通过系统工程理论进行管理创新，实现管理模式的标准化和制度化。文章首先介绍了当前海... 详细信息

文章探讨了海外油田开发中终端处理厂管理的挑战与应对策略，特别是在油田增产上产工程建设期，终端处理厂面临复杂生产作业态势和高风险环境，亟需通过系统工程理论进行管理创新，实现管理模式的标准化和制度化。文章首先介绍了当前海外油田开发中终端处理厂面临的问题和挑战，包括管理机制、制度建设、管理考核等方面；其次，详细阐述了系统工程在终端处理厂管理中的应用，通过成立系统管理工作委员会和多个专项工作组，实施联防联治、工艺联动、信息化管理等策略，以提升管理效率和应对潜在风险；最后，通过中东某中资企业的案例分析，展示了系统化管理理论在终端处理厂应用后的成效，包括风险防控、隐患治理、应急响应和员工培训等方面的提升。最终得出结论，系统化管理模式的引入和优化对提升终端处理厂的管理效率和确保油田安全平稳运行具有重要意义。

关键词：终端处理厂管理机制风险应对系统工程

乙肝病毒相关慢加急性肝衰竭患者中PMN-MDSC的表达及意义

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南京医科大学学报（自然科学版） 2024年第6期44卷 838-844页

作者：孙健戚健君杨剑全斌黄建军余雪平侯为顺皖南医学院弋矶山医院感染性疾病科安徽芜湖241001 皖南医学院弋矶山医院检验科安徽芜湖241001 福建医科大学泉州第一医院感染性疾病科福建泉州362000

目的:探讨乙肝病毒相关慢加急性肝衰竭(hepatitis B virus-related acute-on-chronic liver failure,HBV-ACLF)患者中多核型髓源性抑制细胞(polymorphonuclear myeloid-derived suppressor cell,PMN-MDSC)的表达及意义。方法:选取2022年9月—2023年8月皖南医学院弋矶山医院收治的HBV-ACLF患者40例为研究组,同期在该院诊治或体检的慢性乙肝(chronic hepa-titis B,CHB)患者20例、健康对照(healthy control,HC)10例为对照组,收集临床资料,留取血标本。流式细胞术检测入院当日外周血PMN-MDSC频率,比较研究组和两个对照组外周血PMN-MDSC频率的差异。采用Spearman检验分析HBV-ACLF外周血PMN-MDSC频率与炎症指标、疾病严重度的相关性。分别根据是否合并或继发感染及访视期第28天预后情况对HBV-ACLF患者分组,比较各组外周血PMN-MDSC频率的差异。结果:HBV-ACLF组外周血PMN-MDSC频率显著高于CHB组和HC组(P均<0.001),CHB组和HC组之间PMN-MDSC频率差异无统计学意义。HBV-ACLF外周血PMN-MDSC频率与白细胞计数、中性粒细胞淋巴细胞比值、降钙素原水平、国际标准化比值、总胆红素水平、Child-Turcotte-Pugh评分、终末期肝病模型评分均呈正相关(r=0.347、0.799、0.506、0.450、0.462、0.470、0.481,P均<0.05),与淋巴细胞计数呈负相关(r=-0.428,P<0.01)。40例HBV-ACLF患者中,合并感染18例,继发感染17例,28 d预后差21例,其外周血PMN-MDSC频率均高于对照组患者,差异有统计学意义(P均<0.001)。结论:HBV-ACLF患者外周血富集PMN-MDSC,其频率与感染风险、疾病严重度及患者短期预后密切相关。

关键词：髓源性抑制细胞乙型肝炎病毒慢加急性肝衰竭感染预后

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上海市苏州河高水位成因分析及对策研究

中国防汛抗旱 2024年第2期34卷 63-67页

作者：韦浩俞汇李琪易文林上海市水文总站上海200232

近年来,上海市苏州河水位抬升趋势明显,高水位屡次超历史纪录。为分析苏州河高水位抬升趋势和2212号台风“梅花”期间高水位成因,探索高水位变化对策,采用趋势检验法对水位年极值序列进行了趋势检验,并用模型反演台风“梅花”期间水情... 详细信息

近年来,上海市苏州河水位抬升趋势明显,高水位屡次超历史纪录。为分析苏州河高水位抬升趋势和2212号台风“梅花”期间高水位成因,探索高水位变化对策,采用趋势检验法对水位年极值序列进行了趋势检验,并用模型反演台风“梅花”期间水情过程。通过分析,在现状工情水情下,台风“梅花”期间暴雨和风暴潮增水2种影响因子对高水位的影响比例为8∶2。未来,待苏州河西闸和苏州河深隧建成后参与调度,苏州河最高水位可降低0.26 m,若新建黄浦江河口闸,苏州河最高水位可降低0.55 m,可显著提升苏州河两岸尤其是上海市中心城区的防洪排涝能力。

关键词：高水位苏州河台风“梅花” 趋势检验上海市

基于能量算子与Kaiser窗的电压闪变参数检测

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电气自动化 2024年第2期46卷 51-53,58页

作者：祁超米小兵陈力魏敏捷上海电力大学计算机科学与技术学院上海201306 江苏林洋能源股份有限公司江苏南通226299 上海电力大学电气工程学院上海201306

电压闪变对电网安全带来许多负面影响。为了快速检测电压闪变,提出一种基于能量算子与Kaiser组合余弦窗的双谱线改进FFT的闪变参数检测算法。通过能量算子算法提取闪变波动信号。利用基于Kaiser窗的组合余弦窗函数的双谱线插值算法对FF... 详细信息

电压闪变对电网安全带来许多负面影响。为了快速检测电压闪变,提出一种基于能量算子与Kaiser组合余弦窗的双谱线改进FFT的闪变参数检测算法。通过能量算子算法提取闪变波动信号。利用基于Kaiser窗的组合余弦窗函数的双谱线插值算法对FFT进行改进,对闪变信号进行校正分析,得到准确的信号参数。仿真试验结果表明,所提算法可以有效克服单、多频率调制以及基波变动的影响,有稳定性好、计算量小和准确度高等优点。

关键词：电能质量电压闪变 Kaiser窗能量算子最小二乘法

Molecularly imprinted polymer/graphene oxide modified glassy carbon electrode for selective detection of sulfanilamide

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Progress in Natural Science:Materials International 2017年第3期27卷 374-379页

作者： Xiaobing wei Xinhua Xu Wen qi Ying Wu Lihong Wang School of Materials Science and Engineering Tianjin University Analysis and Testing Center Shandong University of Technology Beijing Key Laboratory of Energy Nanomaterials Advance Technology & Materials CoLtdChina Iron & steel Research Institute Group School of Agricultural and Food Engineering Shandong University of Technology

A novel sensitive electrochemical sensor based on a glassy carbon electrode（GCE） modified with molecularly imprinted polymer（MIP） and grapheme oxide（GO） was *** MIP/GO material was prepared by precipitation polymerization in the presence of sulfanilamide as template *** MIP/GO based electrochemical sensor was characterized using scanning electron microscopy（SEM）,cyclic voltammetry（CV）,electrochemical impedance spectroscopy（EIS） and square wave voltammetry（SWV）.The results indicated that the sensor exhibited good affinity and excellent electrochemical response for *** optimized conditions,the oxidation peak current intensity of sulfanilamide showed two linear dynamic ranges from 10 to 1000 ng mL;,and the standard deviation was less than 5% using SWV *** sensor displays good stability,reproducibility,and high *** can be further applied to quantify sulfanilamide in milk.

关键词： Graphene oxide Sulfanilamide Molecularly imprinted polymer Electrochemical detection