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Hysteretic Nonlinearity of Sub-harmonic Emission from Ultrasound Contrast Agent Microbubbles

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Chinese Physics Letters 2011年第4期28卷 126-129页

作者： qiu Yuan-Yuan ZHENG Hai-rong ZHANG Dong Institute of Acoustics Key Lab of Modern AcousticsNanjing UniversityNanjing 210093 Institute of Biomedical and Health Engineering Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518067

Sub-harmonic contrast imaging promises to improve ultrasound imaging quality by taking advantage of increased contrast to tissue *** aim of this study is to examine the hysteretic nonlinearity of sub-harmonic component emitted from *** kinds of microbubble solutions,***■and a self-developed contrast agent,are utilized in the *** hysteretic curves for increasing and decreasing acoustic pressure are theoretically predicted by the Marmottant model and confirmed by *** results reveal that for both microbubble solutions,the development of the rising ramp undergoes three stages,***,growth and saturation;while hysteresis effect appears in the descending *** Vue■microbubbles exhibit better sub-harmonic performance over the self-developed UCAs microbubbles due to the difference of elastic properties of the shell.

关键词： harmonic bubble bubbles

Growth mechanism for zinc coatings deposited by vacuum thermal evaporation

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Journal of Iron and Steel Research International 2021年第8期28卷 1047-1053页

作者： Xiao-pan qiu Xin Liu She-ming Jiang guang-rui Jiang Qi-fu Zhang National Engineering Laboratory of Advanced Coating Technology for Metals Central Iron and Steel Research InstituteBeijing 100081China Beijing Key Laboratory of Green Recyclable Process for Iron and Steel Production Technology Shougang Group Co.Ltd.Research Institute of TechnologyBeijing 100043China

The vacuum thermal evaporation technique was used to simultaneously deposit zinc coatings onto interstitial free steel plates and single-crystal silicon wafers in a high vacuum *** effect of substrate temperature on the mor-phology and crystal orientation of zinc coatings was *** the substrate temperature was 25 and 50℃,the zinc crystallites were plate-like and grew under a particular angle to the substrate *** the substrate was heated to 100℃,the zinc crystallites were regular hexagonal and arranged almost parallel to the substrate *** addition,observation of pure zinc coatings with different thicknesses showed that the growth of zinc coating was mainly in the Volmer-Weber *** the process parameters were appropriate,the zinc coating was composed of closely arranged columnar crystallites,and the crystallites grew preferentially along[0001]direction.

关键词： Vacuum thermal evaporation Zinc coating Deposition temperature Growth mechanism

Lepithiohydimerins A-D:Four Pairs of Neuroprotective Thiohydantoin Dimers Bearing a Disulfide Bond from Maca(Lepidium meyenii Walp.)

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Chinese Journal of Chemistry 2021年第10期39卷 2738-2744页

作者： Xing-rong Peng Ran-Ran Zhang Jun-Hong Liu Zhong-rong Li Lin Zhou Ming-Hua qiu State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan650201 China University of the Chinese Academy of Sciences Beijing 100049China

Main observation and conclusion An HPLC-UV-guided separation was performed and four pairs of unprecedented macathiohydantoin dimers,lepithiohydimerins A—D(1—4)bearing a rare disulfide bond were isolated from the tubers of *** structures were unambiguously confirmed by NMR spectroscopic,X-ray crystallographic and electronic circular dichroism(ECD)*** the concentration of 20μmol/L,compounds 2-1,2-2,and 4-1 increased the viability of PC12 cells with the cell viability at(72.06±1.14)%,(72.64±1.49)%,and(70.93±1.22)%,***,the serial concentration experiment showed that they can protect PC12 cells in a dose-dependent manner.

关键词： Lepidium meyenii Walp. Thiohydantoin dimers Natural products Structure elucidation Biological activity

BACKWARD SCATTERING OF POLARIZED γ+e → H+e REACTION—A SUGGESTION FOR SEARCHING HIGGS BOSONS IN WEINBERG-SALAM MODEL

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Chinese Physics Letters 1984年第1期1卷 39-42页

作者： PENG Hong-an LI Jia-rong qiu Zhong-ping Peking University Hua-Zhong Teachers College

Using the extremely sharp peak of backward cross section for polarized γ+e → H+e processes one could hopefully detect Higgs bosons in W-S model.

关键词： model. backward polarized

Treatment of extracranial internal carotid artery dissecting aneurysm with SUPERA stent implantation:Two case reports

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World Journal of Clinical Cases 2022年第5期10卷 1602-1608页

作者： Min-Jian qiu Bao-rong Zhang Shui-Jiang Song Department of Neurology The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

BACKGROUND There is no standard endovascular treatment for extracranial internal carotid artery dissecting *** the past,stent-graft isolation and stent-assisted coil embolization were commonly used for wide-necked and fusiform ***,we present two cases of extracranial internal carotid artery dissecting aneurysms treated successfully using the SUPERA *** SUMMARY Case 1 was a 57-year-old male patient with sudden right limb weakness and vague speech and diagnosed with cerebral infarction in February *** computed tomographic angiography(CTA)revealed left internal carotid artery dissection with *** at 2 mo showed an eccentric wide-necked dissecting aneurysm(5 mm×5 mm×12 mm,10-mm neck)that was enlarged at 4 mo(7 mm×6 mm×12 mm,11-mm neck).The patient underwent SUPERA stent *** condition was stable in July *** 2 was a 57-year-old man who suddenly felt dizzy and developed unsteady walking in November *** CTA suggested right internal carotid artery dissecting aneurysm(11 mm×9 mm×31 mm)complicated with severe lumen stenosis(95%).The patient underwent SUPERA stent *** patient had no residual symptoms and was stable in December *** SUPERA stent implantation might achieve good results in treating wide-necked or long fusiform internal carotid artery dissecting aneurysms.

关键词： Extracranial Internal carotid artery Dissecting aneurysm Stent Case report

Specific Heat of a Two-Layer Magnetic Superlattice

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Communications in Theoretical Physics 2009年第11期52卷 969-973页

作者： qiu rong-Ke LIANG Jing ZHAO Jian YING Cai-Hong Shenyang University of Technology Shenyang 110023 China

The specific heats of both a two-layer ferromagnetic superlattice and a two-layer ferrimagnetic one *** is found that the spin quantum numbers,the interlayer and intralayer exchange couplings,the anisotropy,theapplied magnetic field,and the temperature all affect the specific heat of these *** both the ferromagneticand ferrimagnetic superlattices,the specific heat decreases with increasing the spin quantum number,the absolutevalue of interlayer exchange coupling,intralayer exchange coupling,and anisotropy,while it increases with increasingtemperature at low *** an applied magnetic field is enhanced,the specific heat decreases in the two-layerferromagnetic superlattice,while it is almost unchanged in the two-layer ferrimagnetic superlattice at low fieldrange at low temperatures.

关键词： ferromagnetic and ferrimagnetic superlattice specific heat anisotropy spin quantum numbers interlayer and intralayer exchange couplings applied magnetic field

Inhibitory gamma-aminobutyric acidergic neurons in the anterior cingulate cortex participate in the comorbidity of pain and emotion

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Neural Regeneration Research 2025年第10期20卷 2838-2854页

作者： Lu Guan Mengting qiu Na Li Zhengxiang Zhou Ru Ye Liyan Zhong Yashuang Xu Junhui Ren Yi Liang Xiaomei Shao Jianqiao Fang Junfan Fang Junying Du Department of Neurobiology and Acupuncture Research Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Key Laboratory for Research of Acupuncture Treatment and Transformation of Emotional Diseases Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Fuchun Community Health Service Center of Fuyang District HangzhouZhejiang ProvinceChina

Pain is often comorbid with emotional disorders such as anxiety and *** of the anterior cingulate cortex has been implicated in pain and pain-related negative emotions that arise from impairments in inhibitory gamma-aminobutyric acid *** review primarily aims to outline the main circuitry(including the input and output connectivity)of the anterior cingulate cortex and classification and functions of different gamma-aminobutyric acidergic neurons;it also describes the neurotransmitters/neuromodulators affecting these neurons,their intercommunication with other neurons,and their importance in mental comorbidities associated with chronic pain *** understanding on their role in pain-related mental comorbidities may facilitate the development of more effective treatments for these ***,the mechanisms that regulate gamma-aminobutyric acidergic systems remain *** is also unclear as to whether the mechanisms are presynaptic or *** exploration of the complexities of this system may reveal new pathways for research and drug development.

关键词： anterior cingulate cortex anxiety chronic pain circuit communication comorbidity depression gamma-aminobutyric acidergic neurons parvalbumin neurons synaptic transmission

A hybrid-stress element based on Hamilton principle

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Acta Mechanica Sinica 2010年第4期26卷 625-634页

作者： Song Cen Tao Zhang Chen-Feng Li Xiang-rong Fu Yu-qiu Long Department of Engineering Mechanics School of Aerospace Tsinghua University Beijing 100084 China Civil and Computational Engineering Centre School of Engineering Swansea University Swansea SA2 8PP UK College of Water Conservancy and Civil Engineering China Agriculture University Beijing 100083 China Department of Civil Engineering Tsinghua University Beijing 100084 China

A novel hybrid-stress finite element method is proposed for constructing simple 4-node quadrilateral plane elements, and the new element is denoted as HH4-3fl here. Firstly, the theoretical basis of the traditional hybrid-stress elements, i.e., the Hellinger-Reissner variational principle, is replaced by the Hamilton variational principle, in which the number of the stress variables is reduced from 3 to 2. Secondly, three stress parameters and corresponding trial functions are introduced into the system equations. Thirdly, the displacement fields of the conventional bilinear isoparametric element are employed in the new models. Finally, from the stationary condition, the stress parameters can be expressed in terms of the displacement parameters, and thus the new element stiffness matrices can be obtained. Since the required number of stress variables in the Hamilton variational principle is less than that in the Hellinger-Reissner variational principle, and no additional incompatible displacement modes are considered, the new hybrid-stress element is simpler than the traditional ones. Furthermore, in order to improve the accuracy of the stress solutions, two enhanced post-processing schemes are also proposed for element HH4-3β. Numerical examples show that the proposed model exhibits great improvements in both displacement and stress solutions, implying that the proposed technique is an effective way for developing simple finite element models with high performance.

关键词： Finite element Hamilton variational principle Hybrid-stress element Post-processing schemes

A sensitive and rapid UV-vis spectrophotometry for organophosphorus pesticides detection based on Ytterbium(Yb3+) functionalized gold nanoparticle

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Chinese Chemical Letters 2018年第12期29卷 1845-1848页

作者： Yuan Li Qingjiao Luo rong Hu Zongbao Chen Ping qiu Department of Chemistry Nanchang UniversityNanchang 330031China Jiangxi Medical Device Testing Center Nanchang 330047China School of Chemistry and Environmental Science Shangrao Normal UniversityShangrao 334001China

A kind of sensitive, rapid, and simple spectrophotometry based on a Ytterbium(Yb3+) functionalized gold nanoparticle(Au NPs-Yb) was developed for detection of organophosphorus pesticides(OPs). Prepared AuNPs possess oxygen-containing functional groups and strong complexation reaction with Yb3+. While oxygen-containing thiophosphate in the OPs molecule can combine with Yb3+as a cross-linking molecule to produce insoluble yetterbium phosphate, resulting in the aggregation of AuNPs and great decrease in ultraviolet absorbance strength at 520 nm by ultraviolet visible(UV-vis) spectrophotometer. Under the optimized conditions, a linear relationship between the absorbance of AuNPs and OPs concentration ranged from 0.05 μg/L to 6.0 μg/L with limit of detection for 0.03 μg/L(S/N = 3), which is far lower than the maximum residue limit(0.01 ppm) in the European Union pesticides database. Therefore, this assay has potential application in the determination of OPs in the field of environmental and food monitoring.

关键词： Ytterbium Gold nanoparticles Spectrophotometry Organophosphorus pesticides Coordination-bonding interaction