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发动机盖外板全工序成形仿真及回弹补偿研究

汽车工程师 2021年第7期 18-22页

作者：蒋磊王龙谢蛟龙马培兵何奇志崔迎君东风本田汽车有限公司新车型中心东风模具冲压技术有限公司模具分公司

以某车型发动机盖外板为研究对象,对其全工序冲压成形过程以及真实回弹情况进行了探索。根据产品结构特点,分析了其全工序成形工艺,并利用CATIA软件设计了3工序化的冲压工艺数模。借助AutoForm软件对发动机盖外板全工序成形性进行了有... 详细信息

以某车型发动机盖外板为研究对象,对其全工序冲压成形过程以及真实回弹情况进行了探索。根据产品结构特点,分析了其全工序成形工艺,并利用CATIA软件设计了3工序化的冲压工艺数模。借助AutoForm软件对发动机盖外板全工序成形性进行了有限元分析,然后在成形工艺稳健的前提下模拟了零件的真实回弹。结合回弹仿真结果,在CATIA软件中对发动机盖外板工艺模面进行了补偿。最后将获得补偿的工艺模面应用于冲压模具的加工,并用有限元分析结果指导现场试模,得到无开裂、起皱的合格零件。运用蓝光扫描仪对零件进行精度检测,测量报告显示零件匹配面尺寸偏差均在±0.5mm以内,满足了发动机盖外板尺寸公差要求。研究表明,基于全工序成形的回弹补偿可有效控制发动机盖外板的尺寸精度。

关键词：发动机盖外板全工序工艺模面成形仿真真实回弹回弹补偿尺寸公差

Mediating Mesenchymal Stem Cells Responses and Osteopontin Adsorption via Oligo(ethylene glycol)-amino Mixed Self-assembled Monolayers

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Journal of Materials Science & Technology 2016年第9期32卷 966-970页

作者： Lijing Hao Tianjie Li Naru Zhao Fuzhai cui Chang Du yingjun Wang School of Materials Science and Engineering South China University of TechnologyGuangzhou 510640China National Engineering Research Center for Tissue Restoration and Reconstruction Guangzhou 510006China Department of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

Oligo（ethylene glycol）（-OEG） and amino （-NH2） mixed self-assembled monolayers （SAMs） were employed as model substrates to investigate the effect of charge density on the fate of mesenchymal stem cells （MSCs） and osteopontin （OPN） adsorption. We found that all surfaces presenting -NH2 groups favored cell responses regardless of the surface charge. Meanwhile, OPN adsorption could remain stable on the mixed SAMs over a certain range of charge densities. Our work provides some insights into cell responses and protein adsorption to surface charge.

关键词： Mixed self-assembled monolayers Oligo(ethylene glycol)-amino Mesenchymal stem cell Osteopontin

转录因子NbMYB1R1通过促进活性氧积累抑制病毒侵染

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中国农业科学 2024年第8期57卷 1490-1505页

作者：姜兴林于连伟付涵艾妞崔荧钧李好海夏子豪袁虹霞李洪连杨雪施艳河南农业大学植物保护学院河南省植物保护新技术推广协会河南省植物保护检疫站沈阳农业大学植物保护学院河南省粮食作物协同创新中心小麦玉米作物学国家重点实验室河南农业大学作物学博士后流动站

【背景】黄瓜绿斑驳花叶病毒（cucumber green mottle mosaic virus,CGMMV）是我国重要的检疫性植物病毒，严重降低了世界范围内蔬菜以及瓜类的产量。MYB蛋白家族庞大，功能多样，存在于所有真核生物中。大多数MYB作为转录因子控制植物... 详细信息

【背景】黄瓜绿斑驳花叶病毒（cucumber green mottle mosaic virus,CGMMV）是我国重要的检疫性植物病毒，严重降低了世界范围内蔬菜以及瓜类的产量。MYB蛋白家族庞大，功能多样，存在于所有真核生物中。大多数MYB作为转录因子控制植物的发育和代谢，并对植物应对生物和非生物胁迫反应起重要的调控作用。前期研究显示CGMMV侵染后可以显著上调寄主转录因子基因NbMYB1R1的表达。【目的】明确NbMYB1R1参与CGMMV侵染的机制，为CGMMV病害防控提供理论依据。【方法】运用MEGA 7.0构建系统进化树，对NbMYB1R1的氨基酸序列进行系统进化分析；通过构建NbMYB1R1的荧光表达载体，转化GV3101农杆菌后浸润本氏烟叶片，激光共聚焦显微镜观察其亚细胞定位；利用qRT-PCR技术分析NbMYB1R1在CGMMV侵染不同时期的转录水平及NbMYB1R1沉默烟草植株中活性氧（reactive oxygen species,ROS）相关基因的转录变化；通过沉默NbMYB1R1及下游调控基因NbAOX1a和NbAOX1b，分析NbMYB1R1及下游调控基因NbAOX1a和NbAOX1b在CGMMV侵染过程中的作用；瞬时过表达NbMYB1R1和NbMYB1R1关键氨基酸突变体，分析NbMYB1R1对CGMMV侵染的影响；使用台盼蓝染色以及DAB染色观察瞬时过表达NbMYB1R1造成的细胞死亡是否与程序性细胞死亡（programmed cell death,PCD）以及ROS的积累有关；运用酵母双杂交技术验证NbMYB1R1是否与CGMMV相关蛋白互作。【结果】系统进化树分析表明，NbMYB1R1属于1R MYB大类并与多种烟草的MYB转录因子同源性极高；亚细胞定位结果显示NbMYB1R1定位于细胞核；在CGMMV侵染的烟草植株中，NbMYB1R1的转录水平对比健康植株有明显变化，在CGMMV侵染8、12 d时NbMYB1R1的转录水平显著上调；在沉默内源基因NbMYB1R1的植株上接种CGMMV,3 d后NbMYB1R1沉默植株系统叶出现斑驳、卷曲症状，而对照植株在3.5 d时才出现症状；同时CGMMV CP mRNA水平和蛋白水平检测结果也表明沉默NbMYB1R1可以有效促进CGMMV的积累；在本氏烟叶片瞬时过表达NbMYB1R1及其突变体3 d时检测CGMMV蛋白水平表达量，结果显示过表达NbMYB1R1可以有效抑制CGMMV的侵染，DNA结合结构域缺失后会减轻NbMYB1R1对CGMMV的抑制；台盼蓝和DAB染色结果表明，在瞬时过表达NbMYB1R1蛋白后导致ROS积累并引起细胞死亡；在沉默内源基因NbMYB1R1的植株叶片上检测ROS相关基因的转录水平，发现交替氧化酶基因AOX1a、AOX1b转录水平显著上调；在沉默内源基因NbAOX1a和NbAOX1b的植株上接种CGMMV,4 d后NbAOX1a和NbAOX1b沉默植株系统叶出现斑驳、卷曲症状，而对照植株在3.5 d时就出现症状；同时CGMMV CP mRNA水平和蛋白水平检测结果也表明沉默NbAOX1a和NbAOX1b可以有效抑制CGMMV的积累；酵母双杂交结果显示NbMYB1R1不与CGMMV编码蛋白直接相互作用。【结论】随着CGMMV侵染，防御相关基因NbMYB1R1表达上调，从而抑制下游基因AOX1a、AOX1b的表达并激活细胞内产生ROS抑制病毒侵染，但NbMYB1R1不是通过与CGMMV病毒蛋白直接互作而产生此作用。由此可见，NbMYB1R1在CGMMV侵染过程中发挥了重要作用。

关键词：黄瓜绿斑驳花叶病毒 Nb MYB1R1 转录因子致病机制活性氧

玉米黄花叶病毒在河南省小麦玉米上的分布及其CP序列分析

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植物病理学报 2024年第2期54卷 476-480页

作者：谢莉娜张玉阳于连伟徐永伟杨雪王亚飞陈琳琳李洪连崔荧钧施艳河南农业大学植物保护学院郑州450002 河南省粮食作物协同创新中心郑州450002 小麦玉米作物学国家重点实验室郑州450002 河南省植物保护检疫站郑州450002 河南省植物保护新技术推广协会郑州450002

0 引言.河南省是我国玉米小麦的种植大省,玉米和小麦的种植面积常年保持在3 800千公顷和5 670千公顷以上。玉米黄花叶病毒(maize yellow mosaic virus, MaYMV)是2016年在我国云南省玉米上首次发现的一种新病毒[1],属于马铃薯卷叶病毒属(... 详细信息

0 引言.河南省是我国玉米小麦的种植大省,玉米和小麦的种植面积常年保持在3 800千公顷和5 670千公顷以上。玉米黄花叶病毒(maize yellow mosaic virus, MaYMV)是2016年在我国云南省玉米上首次发现的一种新病毒[1],属于马铃薯卷叶病毒属(polerovirus),能够引起玉米植株叶片黄化、花叶、红叶等症状[6],之后该病毒在亚洲[1-2]、非洲[3-4]、南美洲[5]等地区禾本科作物上均有发现.

关键词：禾本科作物马铃薯Y病毒属叶片黄化玉米植株混合侵染花叶序列分析

Two competitive nucleation mechanisms of calcium carbonate biomineralization in response to surface functionality in low calcium ion concentration solution

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Regenerative Biomaterials 2015年第3期2卷 187-195页

作者： Hua Deng Shuo Wang Xiumei Wang Chang Du Xingcan Shen yingjun Wang Fuzhai cui State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Department of Chemistry and Biochemistry Jackson State UniversityJacksonMS 39203USA School of Materials Science and Engineering South China University of TechnologyGuangzhou 510641China Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Chemical EngineeringGuangxi Normal UniversityGuilin 541004China

Four self-assembled monolayer surfaces terminated with–COOH,–OH,–NH_(2)and–CH_(3)functional groups are used to direct the biomineralization processes of calcium carbonate(CaCO_(3))in low Ca^(2+)concentration,and the mechanism of nucleation and initial crystallization within 12 h was further ***-COOH surface,nucleation occurs mainly via ion aggregation mechanism while prenucleation ions clusters may be also ***-OH and-NH_(2)surfaces,however,nucleation forms via calcium carbonate clusters,which aggregate in solution and then are adsorbed onto surfaces following with nucleation of amorphous calcium carbonate(ACC).Furthermore,strongly negative-charged-COOH surface facilitates the direct formation of calcites,and the-OH and-NH_(2)surfaces determine the formation of vaterites with preferred crystalline *** ACC nor crystalline CaCO_(3)is observed on-CH_(3)*** findings present a valuable model to understand the CaCO_(3)biomineralization pathway in natural system where functional groups composition plays a determining role during calcium carbonate crystallization.

关键词： calcium carbonate biomineralization self-assembled monolayer prenucleation clusters ions adsorption

Influences of cerium on structure and catalytic performance of n-heptane hydroisomerization of Ni-HPW/MCM-48

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Journal of Rare Earths 2015年第1期33卷 46-55页

作者：汪颖军崔莹雪所艳华张微 College of Chemistry and Chemical Engineering Northeast Petroleum University

By means of X-ray diffraction（XRD）, N2 adsorption-desorption, Fourier transform infrared spectroscopy（FT-IR）, scanning electron microscopy（SEM）, NH3-temperature（NH3-TPD）, Py-infrared（Py-IR） and thermogravimetry-differential scanning calorimetry（TG/DTA） techniques, the influences of Ce on the structure, acidity, stability and hydroisomerization performance of Ni-HPW/MCM-48 and Ni-HPW/Ce-MCM-48 catalysts were studied. The results showed that introduction of appropriate content of Ce into MCM-48 could improve the crystallinity, acidity and stability of mesoporous silica. The acidity and stability of the Ni-HPW/Ce-MCM-48 catalyst was also increased. Besides, the catalytic performance of the Ni-HPW/Ce-MCM-48 catalyst for n-heptane hydroisomerization was promoted. The conversion and selectivity of the Ni-HPW/Ce-MCM-48 catalyst reached 41% and 91% respectively at the preparation conditions of 4 wt.% Ni, 20 wt.% HPW, 0.03 Ce/Si molar ratio.

关键词： n-heptane hydroisomerization MCM-48 cerium rare earths

Emission and optical characteristics of brown carbon in size-segregated particles from three types of Chinese ships

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Journal of Environmental Sciences 2024年第8期142卷 248-258页

作者： Fengqin Yang Fan Zhang Zeyu Liu yingjun Chen Yan Zhang Can Wu Yali Lei Shijie Liu Binyu Xiao Xinyi Wan Yubao Chen Yong Han Min cui Cheng Huang Gehui Wang Key Lab of Geographic Information Science of the Ministry of Education School of Geographic SciencesEast China Normal UniversityShanghai 200241China Institute of Eco-Chongming 20 Cuiniao Rd.ChongmingShanghai 202150China State Environmental Protection Key Laboratory of Formation and Prevention of the Urban Air Pollution Complex Shanghai Academy of Environmental SciencesShanghai 200233China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China Department of Civil and Environmental Engineering and State Key Laboratory of Marine Pollution The Hong Kong Polytechnic UniversityKowloon 100872Hong KongChina College of Environmental Science and Engineering Yangzhou UniversityYangzhou 225009China

Brown carbon(BrC)is one of the important light absorption substances that have high light absorption ability under short wavelength ***,limit studies have focused on the BrC emission from *** this study,size-segregated particulate matters(PM)were collected from three different types of ships,light absorption characteristics and size distribution of methanol-soluble BrC and water-soluble BrC in PM from ship exhausts were *** showed that four-stroke low-power diesel fishing boat(4-LDF)had the highest mass concentrations of methanol-soluble organic carbon(MSOC)and water-soluble organic carbon(WSOC),followed by 2-stroke high-power heavy-fuel-oil vessel(2-HHV),and fourstroke high-power marine-diesel vessel(4-HMV).While 2-HHV had obviously higher light absorption coefficients of methanol-soluble BrC(Abs365,M)and water-soluble BrC(Abs365,W)in unit weight of PM than the other two types of *** tested ships presented comparable or higher absorption efficiency of BrC in water extracts(MAE365,W)compared with other BrC emission *** of BrC was concentrated in fine particles,and the particle size distributions of both Abs365,Mand Abs365,Wshowed bimodal patterns,peaking at0.43–0.65μm and 4.7–5.8μm,***,different particle size distributions were found for MAE365,Mbetween diesel and heavy fuel oil ***,different wavelength dependence in particles with different size were also *** exhaust could be confirmed as a non-ignorable BrC emission source,and complex influencing factor could affect the light absorption characteristics of ship *** size should also be considered when light absorption ability of BrC was evaluated.

关键词： Ship emission Brown carbon Light absorption Size distribution

Properties of polydimethylsiloxane hydrophobic modified duplex microarc oxidation/diamond-like carbon coatings on AZ31B Mg alloy

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Journal of Magnesium and Alloys 2021年第4期9卷 1291-1303页

作者： Xue-Jun cui Chuang-Ming Ning Guang-An Zhang Lun-Lin Shang Li-Ping Zhong Ying-Jun Zhang School of Materials Science and Engineering Sichuan University of Science and EngineeringZigong 643000China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Key Laboratories of Fine Chemicals and Surfactants in Sichuan Provincial Universities Zigong 643000China

A reliable,high-performance coating procedure was developed using PDMS to modify a duplex MAO/DLC coating on an AZ31B Mg ***,the duplex MAO/DLC coating was fabricated via a combined MAO and unbalanced magnetron sputter ***,a PDMS solution was used to modify the MAO/DLC coating via a conventional dip-coating *** surface characteristics,bond strength,hardness,tribological behaviour,and corrosion resistance of the coated samples were evaluated via SEM,CA,Raman spectroscopy,friction and wear behaviour,polarisation curve,and NSS *** PDMS modification reduced the HIT of MAO/DLC coating from 15.96 to 8.34GPa;this is ascribed to the penetration of PDMS,which has good rheological properties to form a viscoelastic Si-based organic polymer layer on the MAO/DLC ***,the PDMS-modified MAO/DLC coating was denser,hydrophobic,and had higher bond strength compared with MAO-and MAO/DLC-coated ***,the PDMS modification reduced the COF and wear rate of the duplex MAO/DLC *** indicates that the PDMS improved the tribological behaviour owing to the transferred Si oxide that originated from the Si-O network of the PDMS,as well as the low graphitisation of the DLC layer during ***,the corrosion current density of the MAO/DLC-coated sample modified by PDMS for 10min decreased by two order of magnitude compared with that of the MAO/DLC-coated sample but by five orders of magnitude compared with that of the bare *** NSS tests proved that the PDMS layer slowed the corrosion of the Mg alloy under long-term service,enhancing the corrosion protection *** results are attributed to the high bond strength and lubricant MAO/DLC layer,and the dual role of sealing and hydrophobicity of ***,PDMS modification is promising for the fabrication of protective materials for Mg alloys that require corrosion and wear resistance.

关键词： Magnesium alloy Microarc oxidation Diamond-like carbon Polydimethylsiloxane Tribological behaviour Corrosion resistance

Delayed Visual Recovery from Optic Nerve Injury Following a Procedure of Orbital Wall Reconstruction

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Journal of Biosciences and Medicines 2020年第1期8卷 38-41页

作者： Chengzhe Wu yingjun Li Xun cui Zhengri Li Department of Ophthalmology Affiliated Hospital of Yanbian University Yanji China Department of Ophthalmology Medical School Yanbian University Yanji China

The acute onset of the vision loss by optic never injury following orbital wall reconstruction, has been reported in 0.5% - 5.0% of the cases. Visual impairment can be recovered within an early period after injury. Delayed visual recovery from optic nerve injury during a procedure of orbital wall reconstruction has not been reported. We report a case of delayed recovery from optic nerve injury which occurred following orbital wall reconstruction. A 78-year-old man underwent orbital wall reconstruction for medial wall fracture and resulting enophthalmos in the right eye, one week after a traffic accident. Immediate after surgery, postoperative visual acuity in the right eye decreased to light perception, and relative afferent pupillary defect (RAPD) was detected. In spite of mega-dose steroid treatment, the visual acuity did not improve. However, 8 months after surgery, visual acuity began to recover to 0.1, and the degree of RAPD decreased. Twelve months after surgery, visual acuity in the right eye was 0.4, and pupillary light reflex was normal. Our report suggests that patients with optic neuropathy by surgery or trauma require long-term follow-up, regardless of early response to mega-dose steroid treatment.

关键词： Visual Loss Delayed Visual Recovery Optic Nerve Injury Mega-Dose Steroid