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Purification of Aromatics over a Promising SO_4^(2-)/ZrO_2 Catalyst

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China Petroleum Processing & Petrochemical Technology 2016年第3期18卷 49-56页

作者： Zhao Qing liu jianfei Yao Jiajia Shi Li Wang Xin The State Key Laboratory of Chemical Engineering East China University of Science and Technology

A promising sulfated zirconia(SZ) was successfully synthesized to remove olefins from aromatics. The effects of type and quantity of precipitant, the concentration of impregnants and the calcination temperature were studied, and the synthesized samples were characterized by XRD, SEM, TG-DTG, FTIR, N_2 adsorption analysis and the FTIR pyridine adsorption(py-IR) techniques. This catalyst was found to be superiorly active as compared with the commercial ROC, which exhibited promising application prospects in industry. The optimum synthesis variables required that SZ was impregnated with 2.0 mol/L sulfuric acid and calcined at 650 ℃, and the precursor was precipitated by ammonium hydroxide to reach eventually a p H value of over 9.46. The addition of SO_4^(2-) species increased the amount of catalytically active t-ZrO_2, which was helpful to an increasing abundance of acid sites for enhancing the activity. Meanwhile, the calcination temperature had a great effect on the structure, composition and properties of sulfated zirconia.

关键词： aromatics sulfated zirconia purification olefin conversion catalyst

Sirt1对创伤弧菌脓毒症中巨噬细胞凋亡的影响及机制

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军事医学 2024年第8期48卷 601-607页

作者：周慧男吴成林刘剑飞张陈周丽君钦可为南方医科大学第二临床学院解放军总医院第六医学中心中心实验室解放军总医院第六医学中心耳鼻咽喉头颈外科医学部研究所华南理工大学医学院

目的在创伤弧菌感染体内外模型探究沉默调节蛋白1(Sirt1)对巨噬细胞凋亡的调控作用及其分子机制。方法通过遗传霉素G418筛选构建Sirt1稳定过表达的小鼠RAW264.7巨噬细胞；采用CCK-8法检测Sirt1过表达在创伤弧菌细胞溶素（VVC）对RAW26... 详细信息

目的在创伤弧菌感染体内外模型探究沉默调节蛋白1(Sirt1)对巨噬细胞凋亡的调控作用及其分子机制。方法通过遗传霉素G418筛选构建Sirt1稳定过表达的小鼠RAW264.7巨噬细胞；采用CCK-8法检测Sirt1过表达在创伤弧菌细胞溶素（VVC）对RAW264.7细胞损伤效应中的调控作用；Western印迹法检测VVC处理RAW264.7细胞中Sirt1过表达及Sirt1激活剂白藜芦醇（RSV）预处理对凋亡相关蛋白聚腺苷二磷酸核糖聚合酶（PARP）、裂解型-PARP(cleaved-PARP)、胱天蛋白酶3(caspase3)、裂解型胱天蛋白酶3(cleaved-caspase3)表达的影响；建立小鼠创伤弧菌脓毒症模型并腹腔注射RSV,12 h后取各组小鼠肺、脾、肝组织，采用免疫组织化学法检测凋亡蛋白cleaved-caspase3的表达，同时收集小鼠腹腔巨噬细胞并用Western印迹法检测凋亡通路蛋白PARP、cleavedPARP、caspase3、cleaved-caspase3及乙酰化p53蛋白的表达变化。结果过表达Sirt1能够降低VVC诱导小鼠巨噬细胞RAW264.7细胞损伤；过表达Sirt1及RSV预处理可降低VVC刺激下RAW264.7细胞中凋亡相关蛋白的表达；在小鼠创伤弧菌脓毒症模型中，RSV预防性给药能降低肺、脾、肝等组织中凋亡标志物cleaved-caspase3的表达，同时降低小鼠腹腔巨噬细胞中凋亡相关蛋白cleaved-PARP、cleaved-caspase3及乙酰化p53的表达。结论 Sirt1能抑制p53的乙酰化并减少小鼠巨噬细胞的凋亡，在创伤弧菌脓毒症中起保护作用。

关键词：创伤弧菌白藜芦醇聚腺苷二磷酸核糖聚合酶胱天蛋白酶3 沉默调节蛋白1 细胞凋亡巨噬细胞

聚乙烯微塑料与镉联合暴露对赤子爱胜蚓的毒性效应及交互作用评估

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环境科学学报 2024年第7期44卷 482-496页

作者：杨晓霞张雪梅舒晓谢蔓莉龚久平杨俊英李必全柴勇刘剑飞重庆市农业科学院农业质量标准与检测技术研究所重庆401329

将蚯蚓(赤子爱胜)分别暴露于不同浓度(0.5、2.5、10、20 g·kg^(-1))的聚乙烯(PE)微塑料(30~50μm)与镉(Cd,1、10 mg·kg^(-1))单独或复合污染土壤中28 d.以个体生长及繁殖、细胞色素P450亚酶(CYP1A2、CYP2B6、CYP2C9与CYP3A4)和小分子... 详细信息

将蚯蚓(赤子爱胜)分别暴露于不同浓度(0.5、2.5、10、20 g·kg^(-1))的聚乙烯(PE)微塑料(30~50μm)与镉(Cd,1、10 mg·kg^(-1))单独或复合污染土壤中28 d.以个体生长及繁殖、细胞色素P450亚酶(CYP1A2、CYP2B6、CYP2C9与CYP3A4)和小分子代谢标记物(代谢组学)多指标为受试终点,并采用生物标记物响应指数法(Biomarker response index,BRI)和联合效应加成指数法(Effect addition index,EAI),评估PE微塑料与Cd复合污染毒性效应及交互作用.暴露试验结果显示,联合胁迫能显著影响Cd的生物累积.联合暴露下,蚯蚓体内Cd的积累受微塑料浓度的影响显著.PE与Cd的交互作用随效应水平的增加由拮抗作用转变为协同作用.20 g·kg^(-1) PE与1 mg·kg(-1) Cd联合暴露,以及10~20 g·kg(-1) PE与10mg·kg^(-1) Cd联合暴露下,CYP2B6及CYP3A4活力显著低于对照水平,提示蚯蚓氧化损伤的产生.基于代谢组识别出的前10位重要的小分子代谢物分别为:十二羟基十二烷酸、3'-磷酸腺苷、肌苷、喹啉酸、亚麻酸衍生物(9Z,11E,13S,15Z)-13-羟基十八碳-9,11,15-三烯酸(13(S)-HOT)、硬脂酸、尿苷、L-胱硫醚、胸苷酸与亮氨酸.PE与Cd联合暴露下,上述小分子代谢物水平均发生显著平变化.PE与Cd联合暴露的毒性作用模式与蚯蚓自身解毒能力受损、脂质代谢、嘌呤、嘧啶代谢及氨基酸代谢紊乱有关.本研究结果有助于精准评估土壤PE微塑料与Cd的复合生态风险,为提升PE微塑料与Cd复合污染生态风险的认知提供科学依据.

关键词：赤子爱胜蚓聚乙烯(PE)微塑料镉细胞色素P450亚酶代谢组学变化水平生物标记物响应指数法效应加成指数法

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循环复幼对水曲柳生长繁殖及生理的影响

植物研究 2024年第5期44卷 721-729页

作者：彭广州刘建飞王巧欣付可琢张烨张晨曦詹亚光东北林业大学生命科学学院哈尔滨150040 林木遗传育种全国重点实验室(东北林业大学) 哈尔滨150040

为解决水曲柳(Fraxinus mandshurica)因年龄效应而导致的插穗生根能力在3年生后显著下降的问题,以4年生水曲柳实生苗为研究对象,探究循环扦插复幼对克服年龄效应的作用,尤其是循环次数和截干处理2个关键因素对水曲柳萌蘖、生长和扦插生... 详细信息

为解决水曲柳(Fraxinus mandshurica)因年龄效应而导致的插穗生根能力在3年生后显著下降的问题,以4年生水曲柳实生苗为研究对象,探究循环扦插复幼对克服年龄效应的作用,尤其是循环次数和截干处理2个关键因素对水曲柳萌蘖、生长和扦插生根的影响,以及循环复幼过程中水曲柳的生理变化。结果表明:循环复幼次数的增加和截干处理都能提高水曲柳的复幼程度,呈现萌生枝数量增加、枝条细化、茎节缩短的特征,同时显著提高扦插再生能力。在循环复幼次数达到3次且叠加截干处理时,与未循环复幼相比萌枝数量提高了6.56倍,生根率提高了7.44倍。循环复幼1~3次,植株生长素吲哚乙酸(IAA)、细胞分裂素(CTK)水平提高,赤霉素(GA3)水平在第3次时才显著提升,而脱落酸(ABA)水平呈逐渐下降趋势;循环复幼后植株中过氧化氢酶(CAT)、过氧化物酶(POD)、超氧化物歧化酶(SOD)活性降低,丙二醛(MDA)和可溶性糖含量减少。这些生理指标变化都与植株幼化状态相符。可见,循环复幼可有效恢复幼化状态,诱导水曲柳形成较高IAA、GA3和较低ABA水平的萌枝,同时降低了抗氧化酶活性、MDA与可溶性糖含量,有利于实现水曲柳复幼,从而提高扦插生根率,实现水曲柳良种的快速高效无性繁殖。

关键词：水曲柳复幼扦插激素抗氧化酶活性可溶性糖含量

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A method of phase demodulation of OFDR based on ARC-DSM algorithm

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Optoelectronics Letters 2022年第1期18卷 13-17页

作者： liu jianfei LI Chao FAN Xujun LUO Mingming LUAN Nannan YANG Wenrong School of Electronic Information Engineering Hebei University of TechnologyTianjin 300401China State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjin 300130China

Aiming at low stability and high harmonic distortion of the traditional phase-generated carrier(PGC)demodulation algorithm,we propose a modified demodulation algorithm for distributed strain sensing in phase-sensitive optical frequency domain reflectometry(OFDR).The proposed algorithm combines the arctangent function and differential-self-multiplying(ARC-DSM),which eliminates the effect of modulation depth and realizes the high precision strain variation *** results show that distortion and harmonic distortion are effectively suppressed by the ARC-DSM *** minimum variation of the measurable static strain is about 0.3μεand the spatial resolution can reach 0.2 m within 270 m range.

关键词： algorithm distortion phase

Venturi tube application in high power test of the SRF module

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Nuclear Science and Techniques 2009年第3期20卷 129-132页

作者： MA Guangming liu jianfei HOU Hongtao MA Zhenyu FU Zechuan ZHANG Zhigang ZHAO Zhentang Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Shanghai Key Lab. of Cryogenics ＆ Superconducting RF Technology Shanghai 201800 China

In the superconducting RF module, the dissipation power of the niobium cavity is an important parameter. In the Superconducting radio frequency (SRF) module's acceptance test at Shanghai Synchrotron Radiation Facility (SSRF), the Venturi tube is used to measure the quality factor of SRF cavity at 4.2 K. During the test, the venturi tube is be calibrated by increasing heat load with internal heater. In this paper, the horizontal test principle and venturi effect are briefly introduced. The authors find out a correct way to calibrate the venturi tubes, the calibration results are presented here. From the calibration results, one can deduce the static loss of each module, the source of static loss is also analyzed.

关键词：文氏管加热器核技术研究

From Strategic Ambiguity to Strategic Clarity——Obama Administration’s Global Strategic Adjustments and ***

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Peace 2013年第3期 2-13页

作者： liu jianfei Institute for International Strategic Studies CPCCC Party School

Since the end of the Cold War,the United States has turned out to be the sole world superpower and possessed the unmatched power,and its international status and security situation reached the best period in its *** the *** has declined relatively,its advantages have not changed *** advantages of the *** determine the essence of the *** strategy,and since the end of the Cold War remains almost intact,which is committed to maintenance of the ***,including 3 core goals:maintaining security,expanding economy and promoting *** the end of the Cold War,all *** have adhered to this hegemonic strategy while making some major adjustments,with some changing expressions and the priorities of the strategic *** should be pointed out that there is an important and possibly dangerous trend in the adjustments,,which is the gradual disappearance of strategic flexibility and strategic *** other words,these global strategic adjustments after the Cold War have been increasingly focusing on China and the Asia-Pacific *** trend is likely to continue in the second term of President Obama and will affect the development of *** to a large extent.

关键词： From Strategic Ambiguity to Strategic Clarity Obama Administration’s Global Strategic Adjustments and China-U.S.Relations

Beam trip diagnostic system at SSRF

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Nuclear Science and Techniques 2009年第5期20卷 261-264页

作者： HOU Hongtao ZHAO Shenjie LUO Chen ZHAO Yubin ZHANG Zhigang FENG Ziqiang MAO Dongqing liu jianfei Shanghai Institute of Applied Physics CAS Shanghai 201800 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Shanghai KEY Laboratory of Cryogenics ＆ Superconducting RF Technology Shanghai 201800 China

In this paper we report the design and realization of beam trip diagnostic system at Shanghai Synchrotron Radiation Facility (SSRF). The system can find out the first fault signal in the key operation signals related to the RF system by analyzing the time sequence, also it can decide which trips occurs first among the three superconducting RF stations. All the states of monitored signals in a time period ahead and behind beam trip are recorded. The results are compared with those from other diagnostic tools at SSRF. The work is of help in improving reliability of the superconducting RF system and stability of the storage ring operation.

关键词： SSRF 核技术同步辐射光源辐射装置

Hospital biosecurity capacitation:Analysis and recommendations for the prevention and control of COVID-19

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Journal of Biosafety and Biosecurity 2020年第1期2卷 5-9页

作者： Hui Ma Jiangong Zhu jianfei liu Xin Zhang Yunxi liu Quansheng Yang The Sixth Medical Center of PLA General Hospital Beijing 100048China Clinical Laboratory of Tai’an Municipal Hospital Tai’an 271000Shandong ProvinceChina The Fifth Medical Center of PLA General Hospital Beijing 100039China Center of Nosocomial Infection Control PLA General HospitalBeijing 100853China

The outbreak of the coronavirus disease 2019(COVID-19)in December 2019 highlighted several concerns regarding hospital biosafety capacitation in the People’s Republic of China,although the epidemic is now under *** study examined the primary problems related to hospital biosecurity,including the absence of a hospital emergency system,inadequate management and control of nosocomial infection,limited hospital laboratory capacity,and poor hospital admission ***,this study puts forward the following countermeasures and suggestions for hospitals to deal with future biosecurity events,such as a major epidemic:first,biosecurity management systems and emergency response mechanisms in hospitals need to be set up;second,the investment and guarantee mechanisms for hospital biosecurity construction should be improved;third,the capacity building of biosecurity incident management requires special attention in general hospitals;and finally,comprehensive plans need to be developed for the integrated construction of medical treatment and prevention facilities through diseasecontrol systems.

关键词： COVID-19 Epidemic Biosecurity Hospital