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Medium and high-entropy transition mental disilicides with improved infrared emissivity for thermal protection applications

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Journal of Materials Science & Technology 2023年第5期136卷 149-158页

作者： Juntao Song yuan Cheng Huimin Xiang Fu-Zhi Dai shun Dong Guiqing Chen ping Hu Xinghong Zhang Wenbo Han Yanchun Zhou Science and Technology on Advanced Composite in Special Environments Laboratory Harbin Institute of TechnologyHarbin 150080China Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China

Transition metal disilicides are widely used as heating elements and infrared emission coatings.However,the limited intrinsic infrared emissivity and high thermal conductivity are the main limitations to their applications as infrared emission coatings in the thermal protection system.To cope with these prob-lems,four medium and high-entropy transition metal disilicides,i.e.,(V_(0.25)Ta_(0.25)Mo_(0.25)W_(0.25))Si_(2)(ME-1),(Nb_(0.25)Ta_(0.25)Mo_(0.25)W_(0.25))Si_(2)(ME-2),(V_(0.2)Nb_(0.2)Ta_(0.2)Mo_(0.2)W_(0.2))Si_(2)(HE-1),and(Cr_(0.2)Nb_(0.2)Ta_(0.2)Mo_(0.2)W_(0.2))Si_(2)(HE-2),were designed and synthesized by spark plasma sintering method using transition metal binary disilicides as precursors.The introduction of multi-elements into transition metal disilicides not only im-proved the infrared emissivity but also reduced the electrical and thermal conductivity.Among them,(Cr_(0.2)Nb_(0.2)Ta_(0.2)Mo_(0.2)W_(0.2))Si_(2)(HE-2)had the lowest electrical conductivity of 3789 S cm-1,which is over one order of magnitude lower than that of MoSi_(2)(50000 S cm^(-1)),and total infrared emissivity of 0.42 at room temperature,which is nearly double of that of TaSi_(2).Benefiting from low electrical conductivity and phonon scattering due to lattice distortion,the medium and high-entropy transition metal disilicides also demonstrated a significant decline in thermal conductivity compared to their binary counterparts.Of all samples,HE-2 exhibited the lowest thermal conductivity of 6.4 W m^(−1)K^(−1).The high-entropy tran-sition metal disilicides also present excellent oxidation resistance at high temperatures.The improved infrared emissivity,reduced thermal conductivity,excellent oxidation resistance,and lower densities of these medium and high-entropy transition metal disilicides portend that they are promising as infrared emission coating materials for applications in thermal protection systems.

关键词： High-entropy ceramics Transition metal disilicides Electrical conductivity Infrared emissivity Thermal conductivity

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Non-invasive respiratory support for patients with novel coronavirus pneumonia:clinical efficacy and reduction in risk of infection transmission

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Chinese Medical Journal 2020年第9期133卷 1109-1111页

作者： Jin-Gen Xia Jian-ping Zhao Zhen-shun Cheng Yi Hu Jun Duan Qing-yuan Zhan Department of Pulmonary and Critical Care Medicine National Clinical Research Center for Respiratory DiseasesChina-Japan Friendship HospitalBeijing 100029China Department of Pulmonary and Critical Care Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430030China Department of Pulmonary and Critical Care Medicine Zhongnan Hospital of Wuhan UniversityWuhanHubei 430071China Department of Pulmonary and Critical Care Medicine The Central Hospital of WuhanWuhanHubei 430030China Department of Surgical Intensive Care Unit China-Japan Friendship HospitalBeijing 100029China

Introduction Pneumonia caused by a novel coronavirus known as 2019 novel coronavirus disease(COVID-19)[1]appeared in Wuhan,China in December 2019,and approximately 15%to 30%of patients developed acute respiratory distress syndrome within a short period of time.[2,3]To reduce respiratory symptoms and improve prognosis,respiratory support is the most important means of life support,[1]and non-invasive respiratory support systems,[2]including various conventional oxygen therapies,non-invasive positive pressure ventilation(NPPV),and high-flow nasal cannula(HFNC),are most commonly used.However,their efficacy and safety remain unclear,and whether they increase the risk of aerosol dispersion and disease transmission is particularly controversial.[4,5]Given that there are many similarities between COVID-19 pneumonia and severe acute respiratory syndrome(SARS)and Middle East respiratory syndrome(MERS),[6]this study primarily discusses clinical indications and provides details regarding the prevention of nosocomial infections during NPPV and HFNC treatment of COVID-19 pneumonia based on previous clinical data on the use of these two therapies for SARS and MERS and our experience with the treatment of COVID-19 pneumonia.

关键词： respiratory pneumonia clinical

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A KAM Theorem for Reversible Systems of Infinite Dimension

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Acta Mathematica Sinica,English Series 2007年第10期23卷 1777-1796页

作者： shun Qing CHEN Xiao ping yuan Department of Mathematics Daxian Normal College Dazhou 635000 P. R. China School of Mathematical Sciences Fudan University Shanghai 200433 P. R. China Key Lab of Mathematics for Nonlinear Science (Fudan University) Ministry of Education Shanghai 200433 P. R. China

For reversible systems of infinite dimension we prove an infinitely dimensional KAM theorem with an application to the network of weakly coupled oscillators of friction. The KAM theorem shows that there are many invar... 详细信息

关键词： KAM theorem reversible system weakly coupled oscillators

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Effect of Kang Ai injection + conventional chemotherapy on tumor markers, apoptotic molecules and immune response in patients with advanced NSCLC

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Journal of Hainan Medical University 2018年第22期24卷 67-70页

作者： Shun-Ping Yuan Bing-Long Huang Wei-ping Huang Qiao-Li Mo Qiang Huang Pharmacy Affiliated XiaoLan Hospital of Southern Medical UniversityZhongshanGuangdong528415China

Objective: To study the effects of Kang Ai injection + conventional chemotherapy on tumor markers, apoptotic molecules and immune response in patients with advanced non-small cell lung cancer (NSCLC). Methods: Patients diagnosed as advanced NSCLC in our hospital during March 2015 - October 2017 were randomly divided into the experimental group receiving Kang Ai injection + conventional chemotherapy and the control group receiving conventional chemotherapy. The contents of tumor markers, apoptotic molecules and immunologic cytokines in serum and the contents of immune cells in peripheral blood were determined before and after chemotherapy. Results: after chemotherapy, the content of CEA, CYFRA21-1, SCC-Ag, GDF15 and Livin in the serum of the two groups decreased significantly, and the content of PDCD5, P53 and Bax increased significantly, and the content of CEA, CYFRA21-1, SCC-Ag, GDF15, Livin in the serum of the experimental group were lower than those of the control group, and the content of PDCD5, P53 and Bax were higher than those of the control group;the content of CD3+ and CD4+ cells in peripheral blood and the content of IFN-γ, IL-2 in serum of control group significantly decreased, whereas the content of CD8+ cells in peripheral blood and the content of IL-4, IL-5 in serum significantly increased after chemotherapy;while the content of CD3+ and CD4+ cells in peripheral blood and the content of IFN-γ, IL-2 in serum of experimental group significantly increased, whereas the content of CD8+ cells in peripheral blood and the content of IL-4, IL-5 in serum significantly decreased after chemotherapy. Conclusion: Kang Ai injection + conventional chemotherapy in the treatment of advanced NSCLC can more significantly decrease the serum tumor markers, regulate the secretion of apoptotic molecules and anti-tumor immune response than conventional chemotherapy.

关键词： Non-small cell lung cancer Kang Ai injection Tumor markers Apoptotic molecules Immune response

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miR-26a regulates mouse hepatocyte proliferation via directly targeting the 3' untranslated region of CCND2 and CCNE2

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Hepatobiliary & Pancreatic Diseases International 2016年第1期15卷 65-72页

作者： Jian Zhou Wei-Qiang Ju Xiao-Peng yuan Xiao-Feng Zhu Dong-ping Wang Xiao-shun He Organ Transplant Center the First Affiliated HospitalSun Yat-Sen University

BACKGROUND： The deficiency of liver regeneration needs to be addressed in the fields of liver surgery, split liver transplan- tation and living donor liver transplantation. Researches of microRNAs would broaden our understandings on the mecha- nisms of various diseases. Our previous research confirmed that miR-26a regulated liver regeneration in mice; however, the relationship between miR-26a and its target, directly or in- directly, remains unclear. Therefore, the present study further investigated the mechanism of miR-26a in regulating mouse hepatocyte proliferation. METHODS： An established mouse liver cell line, Nctc-1469, was transfected with Ad5-miR-26a-EGFP, Ad5-anti-miR-26a- EGFP or AdS-EGFP vector. Cell proliferation was assessed by MTS, cell apoptosis and cell cycle by flow cytometry, and gene expression by Western blotting and quantitative real-time PCR. Dual-luciferase reporter assays were used to test targets of miR-26a. RESULTS： Compared with the Ad5-EGFP group, Ad5-anti- miR-26a-EGFP down-regulated miR-26a and increased prolif- eration of hepatocytes, with more cells entering the G1 phase of cell cycle （82.70%＋1.45% vs 75.80%＋_3.92%）, and decreased apoptosis （5.50%＋0.35% vs 6.73%_＋0.42%）. CCND2 and CCNE2 were the direct targeted genes of miR-26a, miR-26a down- regulation up-regulated CCND2 and CCNE2 expressions and down-regulated p53 expression in Nctc-1469 cells. On the con- trary, miR-26a over-expression showed the opposite results. CONCLUSIONS： miR-26a regulated mouse hepatocyte pro- liferation by directly targeting the 3＇ untranslated regions of cyclin D2/cyclin E2; miR-26a also regulated p53-mediated apoptosis. Our data suggested that miR-26a may be a promis- ing regulator in liver regeneration.

关键词： microRNA miR-26a gene expression hepatocyte proliferation regulation

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Robust restoration of low-dose cerebral perfusion CT images using NCS-Unet

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Nuclear Science and Techniques 2022年第3期33卷 62-76页

作者： Kai Chen Li-Bo Zhang Jia-shun Liu yuan Gao Zhan Wu Hai-Chen Zhu Chang-ping Du Xiao-Li Mai Chun-Feng Yang Yang Chen Southeast University Nanjing 210096China School of Cyber Science and Engineering Southeast UniversityNanjing 210096China Key Laboratory of Computer Network and Information Integration(Southeast University) Ministry of EducationNanjing 210096China Department of Radiology General Hospital of the Northern Theater of the Chinese People’s Liberation ArmyShenyang 110016China Laboratory of Image Science and Technology The School of Computer Science and EngineeringSoutheast UniversityNanjing 210096China Department of Radiology Nanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210008China Jiangsu Key Laboratory of Molecular and Functional Imaging Department of RadiologyZhongda HospitalSoutheast UniversityNanjing 210009China Jiangsu Provincial Joint International Research Laboratory of Medical Information Processing School of Computer Science and EngineeringSoutheast UniversityNanjing 210096China

Cerebral perfusion computed tomography(PCT)is an important imaging modality for evaluating cerebrovascular diseases and stroke symptoms.With widespread public concern about the potential cancer risks and health hazards associated with cumulative radiation exposure in PCT imaging,considerable research has been conducted to reduce the radiation dose in X-ray-based brain perfusion imaging.Reducing the dose of X-rays causes severe noise and artifacts in PCT images.To solve this problem,we propose a deep learning method called NCS-Unet.The exceptional characteristics of non-subsampled contourlet transform(NSCT)and the Sobel filter are introduced into NCS-Unet.NSCT decomposes the convolved features into high-and low-frequency components.The decomposed high-frequency component retains image edges,contrast imaging traces,and noise,whereas the low-frequency component retains the main image information.The Sobel filter extracts the contours of the original image and the imaging traces caused by the contrast agent decay.The extracted information is added to NCS-Unet to improve its performance in noise reduction and artifact removal.Qualitative and quantitative analyses demonstrated that the proposed NCS-Unet can improve the quality of low-dose cone-beam CT perfusion reconstruction images and the accuracy of perfusion parameter calculations.

关键词： Cerebral perfusion CT Low-dose Image denoising Perfusion parameters

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Effects of allitridi on cell cycle arrest of human gastric cancer cells

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World Journal of Gastroenterology 2005年第35期11卷 5433-5437页

作者： Min-Wen Rui Ma Li-ping shun Yue-Hua Gong yuan yuan Cancer Institute of the First Affiliated Hospital of ChinaMedical University Shenyang 110001 Liaoning Province China

AIM: To determine the effect of allitridi on cell cycle of human gastric cancer (HGC) cell lines MGC803 and SGC7901 and its possible mechanism.METHODS: Trypan blue dye exclusion was used to evaluate the proliferation, inhibition of cells and damages of these cells were detected with electron microscope.Flow cytometry and cell mitotic index were used to analyze the change of cell cycle, immunohistochemistry, and RT-PCR was used to examine expression of the p21WAF1 gene.RESULTS: MGC803 cell growth was inhibited by allitridi with 24 h IC50 being 6.4 μg/mL. SGC7901 cell growth was also inhibited by allitridi with 24 h IC50 being 7.3 μg/mL.After being treated with allitridi at the concentration of 12 μg/mL for 24 h, cells were found to have direct cytotoxic effects, including broken cellular membrane, swollen and vesiculated mitochondria and rough endoplasmic reticula,and mass lipid droplet. When cells were treated with allitridi at the concentration of 3, 6, and 9 μg/mL for 24 h, the percentage of G0/G1 phase cells was decreased and that of G2/M phase cells was significantly increased (P = 0.002)compared with those in the group. When cells were treated with allitridi at the concentration of 6 μg/mL, cell mitotic index was much higher (P = 0.003) than that of control group, indicating that allitridi could cause gastric cancer cell arrest in M phase. Besides, the expression levels of p21WAF1 gene of MGC803 cells and p21WAF1 gene of SGC7901 cells were remarkably upregulated after treatment.CONCLUSION: Allitridi can cause gastric cancer cell arrest in M phase, and this may be one of the mechanisms for inhibiting cell proliferation. Effect of allitridi on cells in M phas e may be associated with the upregulation of p21WAF1 genes. This study provides experimental data for clinical use of allitridi in the treatment of gastric carcinoma.

关键词：细胞周期胃癌肿瘤细胞病理机制临床表现

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考虑速度波动区间的城市干线双向绿波协调控制模型

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科学技术与工程 2019年第15期19卷 336-342页

作者：潘媛贾顺平北京交通大学城市交通复杂系统理论与技术教育部重点实验室交通运输学院

城市主干道交通量的增长使干线协调控制受到越来越多城市的青睐,而传统的干线协调控制模型主要基于速度均值进行绿波方案设计。考虑到车辆在实际的行驶过程中受各种因素的影响速度存在一定的波动,以95%置信区间下的绿波设计速度作为速... 详细信息

城市主干道交通量的增长使干线协调控制受到越来越多城市的青睐,而传统的干线协调控制模型主要基于速度均值进行绿波方案设计。考虑到车辆在实际的行驶过程中受各种因素的影响速度存在一定的波动,以95%置信区间下的绿波设计速度作为速度波动区间,在Asymmetrical Multi-BAND(AM-BAND)模型的基础上增加了速度波动区间约束,建立了考虑速度波动区间的干线协调控制模型,以获得最大绿波设计速度及最小绿波设计速度。算例分析与仿真结果表明,改进模型的平均行程时间、平均停车次数等评价指标得到不同程度的改进,带宽利用率提高,绿波协调控制效果得到改善。

关键词：城市交通信号控制干线协调速度波动区间

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Taller-than-wide Sign for Predicting Thyroid Microcarcinoma: Comparison and Combination of Two Ultrasonographic Planes

Taller-than-wide Sign for Predicting Thyroid Microcarcinoma:...

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2014年浙江省超声医学学术年会

作者： Chen shun-ping Hu yuan-ping Chen Bin The First Hospital of Wenzhou Medical University

Purpose To investigate the accuracy of using the taller-than-wide(TTW)sign in two ultrasonographic planes for predicting thyroid microcarcinoma,and confirm the hypothesis that a TTW sign in both transverse and longitu...

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Completely Reversed Flow in the Vertebral Artery Does Not Always Indicate Subclavian Steal Phenomenon

Completely Reversed Flow in the Vertebral Artery Does Not Al...

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2014年浙江省超声医学学术年会

作者： Chen shun-ping Hu yuan-ping Guan Li-jie The First Hospital of Wenzhou Medical University

Purpose To evaluated the causes,differential diagnosis,and clinical significance of completely reversed flow(CRF)in the vertebral artery(VA).Methods Twenty-three patients diagnosed with CRF in the VA by Doppler

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