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Chinese Journal of Polymer Science 2021年第2期39卷 228-236,I0008页

作者： Long Chen xiao Wu xiao-fang zhang Jian-Ming zhang Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plasticsQingdao University of Science&TechnologyQingdao 266042China

Developing an effective method for improving the reproducibility of positive temperature coefficient(PTC)effect is of great significance for large-scale application of polymer based PTC composites,owing to its contribution to the security and ***,we developed a carbon black(CB)/high density polyethylene(HDPE)/poly(vinylidene fluoride)(PVDF)composite with outstanding PTC reproducibility,by incorporating 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([OMIm][NTf2])into the *** multiple repeated temperature cycles,the PTC performance of as-prepared material keeps almost unchanged and the varition of resistance at room temperature is less than 7%.Our studies revealed that[OMIm][NTf2]contributes to the improvement of PTC reproducibility in two ways:(i)it acts as an efficient plasticizer for refining the co-continuous phase morphology of HDPE/PVDE blends;(ii)it inhibits the crystallization of PVDF through the dilution effect,leading to more overlaps of the volume shrinkage process of HDPE and PVDF melt which results in the decrease of interface gap between HDPE and *** study demonstrated that ionic liquids as the multifunctional agents have great potential for improving the reproducibility in the application of the binary polymer based PTC composites.

关键词： Conductive polymer composites Reproducibility Positive temperature coefficient Ionic liquid

Improvement in the performance of solar adaptive optics

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Research in Astronomy and Astrophysics 2014年第4期14卷 471-484页

作者： xiao-fang zhang Lian-Qi Wang School of Optoelectronics Beijing Institute of Technology Thirty Meter Telescope Project 1111 S.Arroyo Pkwy Suite 200Pasadena California 91105USA

Adaptive optics （AO）, which provides diffraction limited imaging over a field-of-view （FOV）, is a powerful technique for solar observation. In the tomographic approach, each wavefront sensor （WFS） is looking at a single reference that acts as a guide star. This allows a 3D reconstruction of the distorted wavefront to be made. The correction is applied by one or more deformable mirrors （DMs）. This technique benefits from information about atmospheric turbulence at different layers, which can be used to reconstruct the wavefront extremely well. With the assistance of the MAOS software package, we consider the tomography errors and WFS aliasing errors, and focus on how the performance of a solar telescope （pointing toward zenith） is related to atmospheric anisoplanatism. We theoretically quantify the performance of the to- mographic solar AO system. The results indicate that the tomographic AO system can improve the average Strehl ratio of a solar telescope in a 10＂ - 80＂ diameter FOV by only employing one DM conjugated to the telescope pupil. Furthermore, we discuss the effects of DM conjugate altitude on the correction achievable by the AO system by selecting two atmospheric models that differ mainly in terms of atmospheric prop- erties at ground level, and present the optimum DM conjugate altitudes for different observation sites.

关键词： instrumentation: adaptive optics -- atmospheric effects -- solar system

Prognostic value of red blood cell distribution width for severe acute pancreatitis

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World Journal of Gastroenterology 2019年第32期25卷 4739-4748页

作者： fang-xiao zhang Zhi-Liang Li Zhi-Dan zhang xiao-Chun Ma Department of Critical Care Medicine First Affiliated Hospital of China Medical University

BACKGROUND Severe acute pancreatitis(SAP)is a common condition in the intensive care unit(ICU)and has a high *** evaluation of the severity and prognosis is very important for SAP ***,red blood cell distribution(RDW)was associated with mortality of sepsis patients and could be used as a predictor of ***,RDW may be associated with the prognosis of SAP patients and be used as a prognostic indicator for SAP *** To investigate the prognostic value of RDW for SAP *** We retrospectively enrolled SAP patients admitted to the ICU of the First Affiliated Hospital of China Medical University from June 2015 to June *** to the prognosis at 90 d,SAP patients were divided into a survival group and a non-survival *** was extracted from a routine blood *** parameters and RDW were recorded and compared between the two *** receiver operator characteristic(ROC)curve was constructed and Cox regression analysis was performed to investigate the prognostic value of RDW for SAP *** In this retrospective cohort study,42 SAP patients were enrolled,of whom 22 survived(survival group)and 20 died(non-survival group).The baseline parameters were comparable between the two *** coefficient of variation of RDW(RDW-CV),standard deviation of RDW(RDW-SD),Acute Physiology and Chronic Health Evaluation II(APACHE II)score,and Sequential Organ Failure Assessment(SOFA)score were significantly higher in the non-survival group than in the survival group(P<0.05).The RDW-CV and RDW-SD were significantly correlated with the APACHE II score and SOFA score,*** areas under the ROC curves(AUCs)of RDW-CV and RDW-SD were all greater than those of the APACHE II score and SOFA score,among which,the AUC of RDW-SD was the *** results demonstrated that RDW had better prognostic value for predicting the mortality of SAP *** the RDW-SD was greater than 45.5,the sensitivity f

关键词： Red blood cell distribution width Severe acute pancreatitis Prognosis Acute Physiology and Chronic Health Evaluation II score Sequential Organ Failure Assessment score

SAGE based iterative receiver for joint synchronization and channel estimation in uplink MIMO-OFDMA systems

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The Journal of China Universities of Posts and Telecommunications 2008年第3期15卷 100-104页

作者： JIANG Zheng QIN xiao-fang zhang Xin CHANG Yong-yu Wireless Theories and Technologies Laboratory Beijing University of Posts and Telecommunications Beijing 100876 China

A new Turbo iterative receiver structure is proposed for the uplink multiple-input multiple-output orthogonal frequency division multiple access （MIMO-OFDMA） systems. The space-alternating generalized expectation-maximization （SAGE） algorithm is naturally embedded in the framework of iterative receiver to perform synchronization and detection usin~ the Turbo detector outputs. In each iteration, the expectation step intends to remove the multiple access interference （MAI） caused by other asynchronous users, and the maximization step is utilized to estimate the required parameters （i.e., timing offset, carrier frequency offset, channel state information, etc.） sequentially for each user. Simulation results show that the proposed algorithm can approach the performance of ideal receiver closely, while the processing complexity is rather lower than the conventional detectors.

关键词： SAGE iterative receiver synchronization channel estimation

Thermal Shock Behavior Analysis of Tungsten-Armored Plasma-Facing Components for Future Fusion Reactor

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Acta Metallurgica Sinica(English Letters) 2018年第5期31卷 515-522页

作者： Shu-Ming Wang Jiang-Shan Li Yan-Xin Wang xiao-fang zhang Qing Ye Department of Materials Science and Engineering University of Science and Technology Beijing

In a fusion reactor, plasma-facing components（PFCs） will suffer severe thermal shock; behavior and performance of PFCs under high heat flux（HHF） loads are of major importance for the long-term stable operation of the reactor. This work investigates the thermo-mechanical behaviors of tungsten armor under high heat loads by the method of finite element modeling and simulating. The temperature distribution and corresponding thermal stress changing rule under different HHF are analyzed and deduced. The Manson–Coffin equation is employed to evaluate the fatigue lifetime（cyclic times of HHF loading） of W-armored first wall under cyclic HHF load. The results are useful for the formulation design and structural optimization of tungsten-armored PFCs for the future demonstration fusion reactor and China fusion experimental thermal reactor.

关键词： Plasma-facing components Thermo-mechanical behavior High heat flux Tungsten armor-Fatigue lifetime Finite element method

Synthesis, Crystal Structure and Characterization of a New Manganese(Ⅱ) Tetracarboxylate

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Chinese Journal of Structural Chemistry 2008年第2期27卷 167-170页

作者： YING Shao-Ming fang xiao-Niu zhang Ding-Wa CHEN Wen-Tong LIU Jiu-Hui Department of Chemistry Jinggangshan College Ji＇an Jiangxi 343009 China

By hydrothermal synthesis, a manganese（H） tetracarboxylate [Mn（2,2′-bipyridi- ne）（btec）0.5（HEO）]En （H4btec = 1,2,4,5-benzenetetracarboxylic acid） was obtained and characterized by single-crystal X-ray diffraction, IR, elemental analysis and thermogravimetric analysis. It crystallizes in triclinic, space group P1, with a = 7.721（4）, b = 8.905（5）, c = 10.712（6）A, a = 80.899（8）, β = 70.371（8）, y = 78.201（8）°, Z = 2, V= 675.8（7）A3, Mr= 354.20, De= 1.741 g/cm^3,μ = 1.007 mm^-1, F（000） = 360, S = 0.956, （△/σ）max = 0.000, the final R = 0.0490 and wR = 0.1262. This compound presents an infinite 1D polymer featuring a double-chain structure. The Mn（Ⅱ） ion is five-coordinated. The four carboxylate groups of btec4- are all deprotonated and coordinated to four Mn atoms in a monodentate fashion, forming a 1D double chain structure with a cavity. Such chains are interconnected by π-π stacking interactions into 2D layers which are further interlinked into a supramolecular structure by hydrogen bonds.

关键词： hydrothermal synthesis tetracarboxylate crystal structure double chain

Longitudinal Image Analysis via Path Regression on the Image Manifold

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Journal of the Operations Research Society of China 2019年第4期7卷 599-614页

作者： Shi-Hui Ying xiao-fang zhang Ya-Xin Peng Ding-Gang Shen Department of Mathematics Shanghai UniversityShanghai 200444China Department of Radiology and BRIC University of North Carolina at Chapel HillChapel HillNC 27599USA

Longitudinal image analysis plays an important role in depicting the development of the brain structure,where image regression and interpolation are two commonly used *** this paper,we develop an efficient model and approach based on a path regression on the image manifold instead of the geodesic regression to avoid the complexity of the geodesic ***,first we model the deformation by diffeomorphism;then,a large deformation is represented by a path on the orbit of the diffeomorphism group *** path is obtained by compositing several small deformations,which can be well approximated by its ***,we introduce some intermediate images as constraints to the model,which guides to form the best-fitting ***,we propose an approximated quadratic model by local linearization method,where a closed form is deduced for the *** actually speeds up the ***,we evaluate the proposed model and algorithm on a synthetic data and a real longitudinal MRI *** results show that our proposed method outperforms several state-of-the-art methods.

关键词： Longitudinal image analysis Path regression Diffeomorphism group Image registration Infant brain development

Long-term outcomes of wedge resection at the limbus for high irregular corneal astigmatism after repaired corneal laceration

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International Journal of Ophthalmology(English edition) 2016年第6期9卷 843-847页

作者： Jun Du Guang-Ying Zheng Cheng-Lin Wen xiao-fang zhang Yu Zhu Department of Ophthalmology the First Affiliated Hospital of Zhengzhou University Department of Ophthalmology People's Hospital of Zhengzhou

AIM： To evaluate the clinical value of wedge resection at corneal limbus in patients with traumatic corneal scarring and high irregular astigmatism. METHODS： Patients with traumatic corneal astigmatism received wedge resection at least 6mo after suture removal from corneal wound. The uncorrected distance visual acuities （UCVA） and best corrected distance visual acuities （BCVA）, pre- and post-operation astigmatism, spherical equivalent （SE）, safety and complications were evaluated. RESULTS： Ten eyes （10 patients） were enrolled in this study. Mean follow-up time after wedge resection was 37.8±15.4mo （range, 20-61mo）. The mean UCVA improved from ＋1.07±0.55 IogMAR to ＋0.43±0.22 IogMAR （P=0.000） and the mean BCVA from ＋0.50±0.30 IogMAR to ＋0.15± 0.17 IogMAR （P=0.000）. The mean astigmatism power measured by retinoscopy was -2.03±2.27 D postoperatively and -2.83±4,52 D preoperatively （P=0.310）. The mean SE was -0.74±1.61 D postoperatively and -0.64±1.89 D preoperatively （P=0.601）. Two cases developed mild pannus near the sutures. No corneal perforation, infectious keratitis or wound gape occurred. CONCLUSION： Corneal-scleral limbal wedge resection with compression suture is a safe, effective treatment for poor patients with high irregular corneal astigmatism after corneal-scleral penetrating injury. Retinoscopy can prove particularly useful for high irregular corneal astigmatism when other measurements are not amenable.

关键词： wedge resection irregular cornealastigmatism ocular trauma

Beneficial effects of metformin on primary cardiomyocytes via activation of adenosine monophosphate-activated protein kinase

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Chinese Medical Journal 2011年第12期124卷 1876-1884页

作者： WANG xiao-fang zhang Jin-ying LI Ling ZHAO xiao-yan Department of Cardiology First Affiliated Hospital College ofMedicine Zhengzhou University Zhengzhou Henan 450052China

Background Metformin has become a cornerstone in the treatment of patients with type-2 diabetes. Accumulated evidence suggests that metformin supports direct cardiovascular effects. The present study aimed to investigate if metformin has beneficial effects on primary cardiomyocytes damaged by H2O2, and reveal the potential mechanism of action of metformin. Methods Cardiomyocytes were incubated in the presence of 100μmol/L H2O2 for 12 hours. Cardiomyocytes were pretreated with metformin at different concentrations and time and with aminoimidazole carboxamide ribonucleotide （AICAR）（500μmol/L）, an adenosine monophophate （AMP）-activated protein kinase （AMPK） agonist for 60 minutes before the addition of H2O2. Other cells were preincubated with compound C （an AMPK antagonist, 20μmol/L） for 4 hours. The viability and apoptosis of cells were analyzed. AMPK, endothelial nitric oxide synthase （eNOS）, and transforming growth factor （TGF）-β1 were analyzed using immunblotting. Results Metformin had antagonistic effects on the influences of H2O2 on cell viability and attenuated oxidative stress-induced apoptosis. Metformin also increased phosphorylation of AMPK and eNOS, and reduced the expression of TGF-β1, basic fibroblast growth factor （bFGF）, and tumor necrosis factor （TNF）-α. Conclusions Metformin has beneficial effects on cardiomyocytes, and this effect involves activation of the AMPK-eNOS pathway. Metformin may be potentially beneficial for the treatment of heart disease.

关键词： adenosine monophosphate-activated protein kinase cardiomyocyte, endothelial nitric oxide synthase metformin transforming growth factor

Applications of HPLC/MS in the analysis of traditional Chinese medicines

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Journal of Pharmaceutical Analysis 2011年第2期1卷 81-91页

作者： Miao Li xiao- fang Hou Jie zhang Si-Cen Wang Qiang Fu Lang- Chong He School of Medicine Xi'an Jiaotong University Xi'an 710061 China

In China, traditional Chinese medicines （TCMs） have been used in clinical applications for thousands of years. The successful hyphenation of high-performance liquid chromatography （HPLC） and mass spectrometry （MS） has been applied widely in TCMs and biological samples analysis. Undoubtedly, HPLC/MS technique has facilitated the understanding of the treatment mechanism of TCMs. We reviewed more than 350 published papers within the last 5 years on HPLC/MS in the analysis of TCMs. The present review focused on the applications of HPLC/MS in the component analysis, metabolites analysis, and pharmacokinetics of TCMs etc. 50% of the literature is related to the component analysis of TCMs, which show that this field is the most popular type of research. In the metabolites analysis, HPLC coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry has been demonstrated to be the powerful tool for the characterization of structural features and fragmentation behavior patterns. This paper presented a brief overview of the applications of HPLC/MS in the analysis of TCMs. HPLC/MS in the fingerprint analysis is reviewed elsewhere.

关键词： traditional Chinese medicines (TCMs) HPLC/MS component analysis metabolites analysis pharmacokinetics