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Can the Prior Cathodic Polarisation Treatment Remove the Air-Formed Surface Film and Is It Necessary for the Potentiodynamic Polarisation Test?

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Acta Metallurgica Sinica(English Letters) 2020年第6期33卷 839-845页

作者： zheng-Rong ye Zhi-Chao Qiu zheng-Bin Wang Yu-Gui zheng Ran Yi Xiang Zhou Research Institute of Petroleum Exploration and Development PetroChinaBeijing 100083China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

This paper clarifies two issues related to the prior cathodic polarisation treatment(PCPT) for the potentiodynamic polarisation test: whether PCPT can(1) remove the air-formed surface film and(2) affect the polarisation test results. X-ray photoelectron spectroscopy analyses of fluoride ion-labelled samples show that PCPT cannot remove the surface film completely due to the low reaction rate. Potentiodynamic polarisation tests demonstrate that PCPT with proper operating parameters,-1.0 V SCE for 5 min with subsequent open circuit potential(OCP) stabilisation in this study, is necessary because it can improve the test reproducibility without affecting the corrosion parameters by unifying the initial surface state. However, PCPT with lower potentials, longer time or no OCP stabilisation has significant effects on the electrochemical corrosion parameters due to the hydrogen absorption under the conditions of this study.

关键词： Stainless steel Prior cathodic polarisation treatment Surface film Potentiodynamic polarisation

Alteration in Secondary Wall Deposition by Overexpression of the Fragile Fiber1 Kinesin-Like Protein in Arabidopsis

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Journal of Integrative Plant Biology 2007年第8期49卷 1235-1243页

作者： Jianli Zhou Jia Qiu zheng-Hua ye Department of Plant Biology University of Georgia Athens Georgia 30602 USA

Secondary walls in fibers and vessels are typically deposited in three distinct layers, which are formed by the successive re-orientation of cellulose microfibrils. Although cortical microtubules have been implicated in this process, the underlying mechanisms for the formation of three distinct wall layers are not known. The Fragile Fiber1 （FRA1） kinesin-like protein has been previously shown to be involved in the oriented deposition of cellulose microfibrils and important for cell wall strength in Arabidopsis thaliana. In the present report, we investigated the expression pattern of the FRA 1 gene and studied the effects of FRA1 overexpression on secondary wall deposition. The FRAI gene was found to be expressed not only in cells undergoing secondary wall deposition including developing interfascicular fibers and xylem cells, but also in dividing cells and expanding/elongating parenchyma cells. Overexpression of FRA1 caused a severe reduction in the thickness of secondary walls in interfascicular fibers and deformation of vessels, which are accompanied with a marked decrease in stem strength. Close examination of secondary walls revealed that unlike the wild-type walls having three typical layers with the middle layer being the thickest, the secondary walls in FRA1 overexpressors exhibited an increased number of layers, all of which had a similar width. Together, these results provide further evidence implicating an important role of the FRA1 kinesin-like protein in the ordered deposition of secondary walls, which determines the strength of fibers and vessels.

关键词： Arabidopsis thaliana cellulose microfibrils kinesin-like protein secondary wall deposition.

Global Analysis of Direct Targets of Secondary Wall NAC Master Switches in Arabidopsis

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Molecular Plant 2010年第6期3卷 1087-1103页

作者： Ruiqin Zhong Chanhui Lee zheng-Hua ye Department of Plant Biology University of Georgia Athens GA 30602 USA

We report the genome-wide analysis of direct target genes of SND1 and VND7, two Arabidopsis thaliana NAC domain transcription factors that are master regulators of secondary wall biosynthesis in fibers and vessels, respectively. Systematic mapping of the SND1 binding sequence using electrophoretic mobility shift assay and transactivation analysis demonstrated that SND1 together with other secondary wall NACs （SWNs）, including VND6, VND7, NST1, and NST2, bind to an imperfect palindromic 19-bp consensus sequence designated as secondary wall NAC binding element （SNBE）, （T/A）NN（C/T）（TICIG）TNNNNNNNA（AIC）GN（AJCIT）（A/T）, in the promoters of their direct targets. Genome-wide analysis of direct targets of SND1 and VND7 revealed that they directly activate the expression of not only downstream transcription factors, but also a number of non-transcription factor genes involved in secondary wall biosynthesis, cell wall modification, and programmed cell death, the promoters of which all contain multiple SNBE sites. SND1 and VND7 directly regulate the expression of a set of common targets but each of them also preferentially induces a distinct set of direct targets, which is likely attributed to their differential activation strength toward SNBE sites. Complementation study showed that the SWNs were able to rescue the secondary wall defect in the sndl nstl mutant, indicating that they are functionally interchangeable. Together, our results provide important insight into the complex transcriptional program and the evolutionary mechanism underlying secondary wall biosynthesis, cell wall modification, and programmed cell death in secondary wall-containing cell types.

关键词： Arabidopsis secondary cell walls NAC transcription factor transcriptional regulation.

A New Information Method to Determinate Corrosion Types from Electrochemical Noise

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Acta Metallurgica Sinica(English Letters) 2015年第4期28卷 449-453页

作者： Jian Li Huan-Jun zheng ye zheng Wei-Kang Kong Ke Wang State Key Laboratory of Precision Measuring Technology and Instrument Tianjin University School of Materials Science and Engineering Tianjin University

Electrochemical noise data in the presence of different corrosion types were analyzed. A correlation between the corrosion type of the observed noise and the entropy rate was recognized. A sequence was transformed from each set of original electrochemical noise signal, then the Markov process M and stationary distribution μ were calculated. Finally, entropy rate of each sequence was obtained by the definition. From the entropy rate, it has been observed that local corrosion showed a lower entropy rate, while uniform corrosion showed a higher entropy rate.

关键词： Entropy rate Stainless steel Corrosion Electrochemical behavior

超声对无名动脉重度狭窄或闭塞性疾病的诊断价值

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中国超声医学杂志 2024年第1期40卷 22-26页

作者：郑烨赵青秦淮牛宏珍田菊濮恬宁陈洁首都医科大学附属北京安贞医院综合超声科

目的探讨彩色多普勒超声检查在无名动脉重度狭窄或闭塞性疾病中的诊断价值。方法回顾性分析经数字减影血管造影(DSA)或CT血管造影CTA确诊的无名动脉重度狭窄或闭塞性疾病22例患者和锁骨下动脉近段重度狭窄或闭塞性疾病30例患者的血管... 详细信息

目的探讨彩色多普勒超声检查在无名动脉重度狭窄或闭塞性疾病中的诊断价值。方法回顾性分析经数字减影血管造影(DSA)或CT血管造影CTA确诊的无名动脉重度狭窄或闭塞性疾病22例患者和锁骨下动脉近段重度狭窄或闭塞性疾病30例患者的血管超声特征，对两组患者血流参数改变发生率进行统计学分析。结果 Kappa一致性检验分析，无名动脉病变直接超声征象与DSA或CTA检查结果之间的一致性较好(Kappa值=0.794,P<0.05)。间接超声征象表现为6例右侧颈动脉出现血流信号方向异常，所有右侧颈内动脉频谱形态均有改变。右侧锁骨下动脉中3例为双向血流信号，所有右侧锁骨下动脉远段均呈单向频谱形态。右侧椎动脉窃血改变19例，椎动脉闭塞3例。无名动脉病变组与锁骨下动脉病变组在颈动脉血流方向及远段血管频谱形态改变上有统计学意义(P<0.05)。结论出现右侧椎动脉窃血合并颈动脉和锁骨下动脉血流信号异常时，要考虑到无名动脉病变的可能，有必要近心段追踪扫查无名动脉。

关键词：超声检查无名动脉重度狭窄闭塞

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不同绿化树种对镉的富集特征

浙江农林大学学报 2024年第4期41卷 752-759页

作者：李业庆郑叶魏奕博王丹李烜桢范国强河南农业大学林学院河南郑州450046 河南农业大学国际教育学院河南郑州450046

【目的】乔木对重金属具有富集能力,但是目前对其积累特征尚不明确,一定程度上限制了乔木修复重金属污染土壤技术的推广应用。探讨5种乔木绿化树种对镉的富集特征。【方法】分析了镉污染土壤上栽植的泡桐Paulownia fortunei、楸树Catalp... 详细信息

【目的】乔木对重金属具有富集能力,但是目前对其积累特征尚不明确,一定程度上限制了乔木修复重金属污染土壤技术的推广应用。探讨5种乔木绿化树种对镉的富集特征。【方法】分析了镉污染土壤上栽植的泡桐Paulownia fortunei、楸树Catalpa bungei、悬铃木Platanus acerifolia、黑杨Populus nigra和垂柳Salix babylonica等树木不同部位对镉的富集特征,并分析了不同树种对镉的积累总量。【结果】供试树种对镉均具有一定的积累能力,单株对镉的积累量为43.01~886.28 mg·株^(-1),其中垂柳对镉的积累总量最大,达886.28 mg·株^(-1);其次是黑杨,达392.51 mg·株^(-1)。不同树种不同部位对镉的富集能力也不同,泡桐、楸树、悬铃木、黑杨和垂柳不同部位的富集系数分别为0.07~0.56、0.10~1.24、0.06~1.04、0.32~1.58、0.06~0.97。其中黑杨多数部位(除茎皮外)的富集系数均大于其他树种。所有树种根皮、茎皮和枝皮的镉质量分数均显著(P<0.05)大于其对应的根材、茎材和枝材。所有树种不同部位镉质量分数与土壤镉质量分数均呈极显著正相关(P<0.01)。【结论】乔木主要将镉积累到枝部和茎部,其中泡桐、楸树和悬铃木主要积累在枝部,黑杨和垂柳主要积累在茎部。此外,黑杨和垂柳具有较高的镉积累量,是今后镉污染土壤修复中的首选树种。

关键词：树木镉积累总量富集系数土壤修复

Enantioselective synthesis of functionalized fluorinated dihydropyrano[2,3-c]pyrazoles catalyzed by a simple bifunctional diaminocyclohexane-thiourea

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Chinese Chemical Letters 2014年第4期25卷 535-540页

作者： Hong-Fei Zhang zheng-Qing ye Gang Zhao Key Laboratory of Synthetic Chemistry of Natural Substances Shanghai Institute of Organic ChemistryChinese Academy of Sciences

Enantioselective synthesis of functionalized fluorinated dihydropyrano[2,3-c]pyrazoles has been achieved via a diaminocyclohexane-thiourea catalyzed cascade Michael addition and Thorpe-Ziegler type cyclization in high... 详细信息

关键词： Trifluoromethyl Pyrazoles Cyclization Organocatalysis

Correction:Cognitive Impairment in Idiopathic Normal Pressure Hydrocephalus

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Neuroscience Bulletin 2022年第9期38卷 1121-1122页

作者： Haoyun Xiao Fan Hu Jing Ding zheng ye Institute of Neuroscience Center for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai200031China University of Chinese Academy of Sciences Beijing100049China Department of Neurosurgery Zhongshan HospitalFudan UniversityShanghai200032China Department of Neurology Zhongshan HospitalFudan UniversityShanghai200032China

Idiopathic normal pressure hydrocephalus (iNPH) is a significant cause of the severe cognitive decline in the elderly population. There is no cure for iNPH, but cognitive symptoms can be partially alleviated through cerebrospinal fluid (CSF) diversion. In the early stages of iNPH, cognitive deficits occur primarily in the executive functions and working memory supported by frontostriatal circuits. As the disease progresses, cognition declines continuously and globally, leading to poor quality of life and daily functioning. In this review, we present recent advances in understanding the neurobiological mechanisms of cognitive impairment in iNPH, focusing on (1) abnormal CSF dynamics, (2) dysfunction of frontostriatal and entorhinal-hippocampal circuits and the default mode network, (3) abnormal neuromodulation, and (4) the presence of amyloid-β and tau pathologies.

关键词： Idiopathic normal pressure hydrocephalus Cognitive impairment Cerebrospinal fluid dynamics Frontostriatal circuits Entorhinal-hippocampal circuits Neuromodulation Amyloid-β pathology Tau pathology

A low-boom and low-drag design method for supersonic aircraft and its applications on airfoils

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Advances in Aerodynamics 2021年第1期3卷 428-454页

作者： Liu-qing ye zheng-yin ye Kun ye Jie Wu Sheng-jie Miao School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China

Sonic boom reduction has been an urgent need for the development of future supersonic transport,because of the heavy damage of noise *** paper provides a novel concept for supersonic aircraft to reduce the sonic boom and drag coefficient,wherein a suction slot near the leading edge and an injection slot near the trailing edge on the airfoil suction surface are *** make sure of a zero net mass flux flow control,the mass flow sucked in near the leading edge is equal to the mass flow injected near the trailing *** diamond and NACA0008 airfoils are adopted as the baseline airfoil to verify the capability of the proposed design *** effects of the suction and injection location,the suction and injection slot size,the mass flow rate and the attack angle on the ground boom signature and drag coefficient are studied in *** results show that the optimized airfoils with the suction and injection have benefits in both sonic boom reduction and wave drag *** the reduction of the sonic boom intensity is more sensitive to the injection near the trailing edge than the suction near the leading *** the viewpoint of aerodynamics,opening the suction and injection slots will have no adverse effect on the aerodynamic performances of the supersonic aircraft and even increase the lift-drag ratio under some *** energy saving,the suction and injection slots can be selectively opened,which are opened when the supersonic aircraft flies over the city but are closed when the aircraft flies over the sea.

关键词： Supersonic flow Sonic boom Supersonic aircraft Optimization Wave drag Low-boom low-drag design