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Analysis of the influence of sheath positions,flight parameters and incident wave parameters on the wave propagation in plasma sheath

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Plasma Science and Technology 2022年第3期24卷 33-40页

作者： Qifan zhang Yiping HAN Qinlu dong Chang dong School of Physics and Optoelectronic Engineering Xidian UniversityXi'an 710071People's Republic of China

The plasma sheath covering hypersonic vehicles has a significant effect on the propagation of electromagnetic *** on the calculation of the flow field of a conical cylindrical,this work studies the propagation of electromagnetic waves in plasma sheath at L-band and Ku-band,and discusses the propagation characteristics in the head,side and tail of the *** dielectric properties of plasma sheath are related to flight speed and altitude.A flight condition corresponds to a unique distribution of dielectric *** the conical cylindrical,the results show that flight speed is generally negatively correlated with the transmissivity of the plasma *** reflection characteristics of electromagnetic waves at the L-band and Kuband when obliquely incident to the plasma sheath show a downward *** the frequency is increased to Ku-band,the propagation characteristics of electromagnetic waves in the plasma sheath are related to the position of the sheath.

关键词： plasma sheath reflection and transmission flow field

Corrosion inhibition of layered double hydroxides for metal-based systems

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Nano Materials Science 2021年第1期3卷 47-67页

作者： Chuan Jing Biqin dong Aikifa Raza Tiejun zhang Yuxin zhang State Key Laboratory of Mechanical Transmissions College of Materials Science and EngineeringChongqing UniversityChongqing400044PR China Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering Shenzhen UniversityShenzhen518060PR China Department of Mechanical Engineering Masdar InstituteKhalifa University of Science and TechnologyP.O.Box 127788Abu DhabiUnited Arab Emirates

Layered double hydroxide(LDH),a kind of 2D layered materials,has been recognized as the promising anticorrosion materials for metal and its *** microstructure,physical/chemical properties,usage in corrosion inhibition and inhibition performance of LDH have been studied separately in open ***,there is a lack of a complete review to summarize the status of LDH technology and the potential R&D opportunities in the field of corrosion *** addition,the challenges for LDH in corrosion inhibition of metal-based system have not been summarized ***,we review recent advances in the rational design of LDH for corrosion inhibition of metal-based system(*** alloy,Al alloy,steel and concrete)and high-throughput anticorrosion materials *** evaluating the physical/chemical properties,usage in metal-based system and the corrosion inhibition mechanism of LDH,we highlight several important factors of LDH for anticorrosion performance and common features of LDH in applying different metal ***,we provide our perspective and recommendation in this field,including high-throughput techiniques for combinatorial compositional design and rapid synthesis of anticorrosion alloys,with the goal of accelerating the development and application of LDH in corrosion inhibition of metal-based system.

关键词： Layered double hydroxide Corrosion inhibition Magnesium alloy Aluminum alloy Steel Concrete

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马来酸氟伏沙明缓释微丸及其压片技术的研究

药学学报 2024年第2期59卷 439-447页

作者：许明慧张兴跃董乔赵峡步玉如陈乐贞中国海洋大学山东青岛266003 青岛海洋生物医药研究院山东青岛266071

本研究旨在制备马来酸氟伏沙明微丸缓释片,并评估其在体外的释药行为。采用离心-滚圆法制备马来酸氟伏沙明载药丸芯,流化床包衣技术制得缓释微丸,并将多单元缓释微丸与处方量的辅料混合压制成片。通过L8(24)田口试验,筛选并确定载药微... 详细信息

本研究旨在制备马来酸氟伏沙明微丸缓释片,并评估其在体外的释药行为。采用离心-滚圆法制备马来酸氟伏沙明载药丸芯,流化床包衣技术制得缓释微丸,并将多单元缓释微丸与处方量的辅料混合压制成片。通过L8(24)田口试验,筛选并确定载药微丸最佳处方;使用Minitab将物料温度、风机转速、雾化压力、喷液速率设计成24部分因子的DOE试验以优化底喷包衣工艺;将24~40目粒径的单硬脂酸甘油酯作为主要稀释剂进行压片以缓解压片时微丸与辅料分层现象并降低包衣膜的机械损伤;对混合颗粒的休止角、堆密度、振实密度、豪斯纳比等粉体流动性指标进行考察发现其流动性和可压性适合直接压片;评价缓释片基本性能,考察体外释放行为,并研究其释放机制。结果表明,马来酸氟伏沙明微丸缓释片可以在pH 6.8的磷酸盐缓冲液中崩解成独立的微丸小单元,并达到24 h缓释的效果,其释药行为符合一级释药模型。制备的马来酸氟伏沙明微丸缓释片,符合制剂设计的释放要求,具有良好的商业前景。

关键词：马来酸氟伏沙明离心-滚圆法流化床包衣多单元缓释微丸粉体学性质体外释放度

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基于形变场灰度场插值网络的切片间超分辨率

计算机与现代化 2024年第3期 67-71页

作者：刘迅张东袁达龙武汉大学物理科学与技术学院湖北武汉430072

磁共振成像是一种常见的医学影像方法。由于硬件等因素的限制,MR图像切片间分辨率会远低于切片内分辨率,图像的质量较低,影响医生对患者病情的诊断,因此需要提高切片间分辨率,以便显示图像更多的细节。为了实现切片间超分辨率,提出一种... 详细信息

磁共振成像是一种常见的医学影像方法。由于硬件等因素的限制,MR图像切片间分辨率会远低于切片内分辨率,图像的质量较低,影响医生对患者病情的诊断,因此需要提高切片间分辨率,以便显示图像更多的细节。为了实现切片间超分辨率,提出一种基于非参数化形变场和灰度场插值网络的算法。首先,根据图像配准原理,利用近似U-Net的网络对低分辨率图像中2张相邻切片进行无监督训练,以生成切片间的双向形变场。然后,利用第一张切片与形变场生成配准后的图像,将配准后的图像与第二张切片进行训练,得到它们之间的双向灰度场,由此得到相邻2张切片中间任意位置的形变场和灰度场。最后,利用插值的方法获得中间的任一位置切片。与其他现有的算法相比,该算法在视觉效果和客观评价指标上都有显著提升,其中PSNR和SSIM分别均在30 dB和0.99以上。

关键词：磁共振成像超分辨率形变场灰度场

WBZUC:novel white-box ZUC-128 stream cipher

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The Journal of China Universities of Posts and Telecommunications 2023年第2期30卷 96-106页

作者： Yang Yatao zhang Ruoqing dong hui Ma Yingjie zhang Xiaowei Department of Electronic and Communication Engineering Beijing Electronic Science and Technology InstituteBeijing 100070China School of Telecommunication Engineering Xidian UniversityXi'an 710071China Hong Kong Applied Science and Technology Research Institute Hong Kong 999077China

White-box cryptography is critical in a communication system to protect the secret key from being disclosed in a cryptographic algorithm code *** stream cipher is a main dataflow encryption approach in mobile ***,research work on white-box cryptographic implementation for stream cipher is rare.A new white-box Zu Chongzhi-128(ZUC-128)cryptographic implementation algorithm named WBZUC was *** adopts lookup table and random coding in the non-linear function to make the intermediate value chaotic without changing the final encryption ***,the WBZUC algorithm’s security gets improved compared with the original ZUC-128 *** for the efficiency,a test experiment on WBZUC shows that the average speed of key generation,encryption,and decryption can reach at 33.74 kbit/s,23.31 kbit/s,24.06 kbit/s *** its running speed is relatively a bit lower than original ZUC-128 algorithm,WBZUC can provide better security and comprehensive performance in mobile communication system environment.

关键词： Zu Chongzhi-128(ZUC-128)algorithm white-box cryptography cryptographic implementation lookup table secure communication

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露珠杜鹃繁育系统及杂交亲和性

植物研究 2024年第3期44卷 370-379页

作者：熊文艳吴雅文白天解玮佳董燕张敬丽云南农业大学园林园艺学院昆明650201 中国热带农业科学院香料饮料研究所万宁571533 云南省农业科学院花卉研究所昆明650205 中国花卉协会北京100102

为种质资源保护和乡土园林树种推广提供技术支持,对野生露珠杜鹃(Rhododendron irroratum)繁育系统和杂交亲和性进行研究,试验包括开花生物学特性,繁育系统特性,与高山杜鹃优良园艺品种杂交授粉,荧光显微镜观察授粉花粉萌发及花粉管生... 详细信息

为种质资源保护和乡土园林树种推广提供技术支持,对野生露珠杜鹃(Rhododendron irroratum)繁育系统和杂交亲和性进行研究,试验包括开花生物学特性,繁育系统特性,与高山杜鹃优良园艺品种杂交授粉,荧光显微镜观察授粉花粉萌发及花粉管生长过程,以及坐果率和结实率统计。结果表明(:1)露珠杜鹃开花时间为4月下旬到5月下旬,花粉活力与柱头可授粉性随开花时间的延长逐渐下降。(2)杂交指数(OCI)为3,P/O值为343.47。(3)主要传粉者为膜翅目中华蜜蜂(Apis cerana),繁育系统为兼性异交型,自交亲和,需要传粉者,属虫媒花。(4)人工控制授粉发现不存在无融合生殖,能自动自花授粉,异株异花、同株异花、自花授粉坐果率分别为46.96%、45.03%、37.16%,人工授粉平均坐果率与自然传粉坐果率基本一致。(5)露珠杜鹃作为亲本进行人工杂交授粉表现出杂交不亲和,母本花粉管中存在胼胝质栓塞,导致花粉管不能延伸至子房。通过观察发现,露珠杜鹃杂交亲和难点在于花粉管生长过程。

关键词：露珠杜鹃繁育系统杂交亲和性荧光显微观察

Using preoperative N-terminal pro-B-type natriuretic peptide levels for predicting major adverse cardiovascular events and myocardial injury after noncardiac surgery in Chinese advanced-age patients

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Journal of Geriatric Cardiology 2022年第10期19卷 768-779页

作者： Kai zhang Chang LIU Jian TAN Yu-hai XU Jiang-Bei CAO Yan-Hong LIU Qiang FU Jing-Sheng LOU Wei-dong MI Hao LI Department of Anesthesiology the First Medical CentreChinese PLA General HospitalBeijingChina Medical School of Chinese PLA BeijingChina Department of Thoracic Surgery the Seventh Medical CentreChinese PLA General HospitalBeijingChina Department of Anesthesiology Air Force Medical CenterBeijingChina

BACKGROUND N-terminal pro-B-type natriuretic peptide(NT-proBNP)is often viewed as an indicator for heart ***,the prognostic association and the predictive utility of NT-proBNP for postoperative major adverse cardiovascular events(MACEs)and myocardial injury after noncardiac surgery(MINS)among older patients are *** In this study,we included 5033 patients aged 65 years or older who underwent noncardiac surgery with preoperative NT-proBNP *** regression was adopted to model the associations between preoperative NT-proBNP and the risk of MACEs and *** receiver operating characteristic curve was used to determine the predictive value of *** A total of 5033 patients were enrolled,63 patients(1.25%)and 525 patients(10.43%)had incident postoperative MACEs and MINS,*** of the receiver operating characteristic curve indicated that the cutoff values of ln(NT-proBNP)for MACEs and MINS were 5.16(174 pg/mL)and 5.30(200 pg/mL),*** preoperative ln(NT-proBNP)to the Revised Cardiac Risk Index score and the Cardiac and Stroke Risk Model boosted the area under the receiver operating characteristic curves from 0.682 to 0.726 and 0.787 to 0.804,*** inclusion of preoperative NT-proBNP in the prediction models significantly increased the reclassification and *** Increased preoperative NT-proBNP was associated with a higher risk of postoperative MACEs and *** inclusion of NT-proBNP enhances the predictive ability of the preexisting models.

关键词： patients preoperative surgery

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迁延不愈的“肺炎”1例

中华结核和呼吸杂志 2024年第9期47卷 845-850页

作者：梁瑞张竹刘东王金志黄强谢万木翟振国北京中医药大学中日友好临床医学院国家呼吸医学中心呼吸和共病全国重点实验室国家呼吸疾病临床研究中心中国医学科学院呼吸病学研究院中日友好医院呼吸中心呼吸与危重症医学科北京国家呼吸医学中心呼吸和共病全国重点实验室国家呼吸疾病临床研究中心中国医学科学院呼吸病学研究院中日友好医院呼吸中心呼吸与危重症医学科北京北京大学中日友好临床医学院国家呼吸医学中心呼吸和共病全国重点实验室国家呼吸疾病临床研究中心中国医学科学院呼吸病学研究院中日友好医院呼吸中心呼吸与危重症医学科北京南昌大学第一附属医院呼吸与危重症医学科南昌国家区域医疗中心中日友好江西医院南昌

大动脉炎肺动脉受累(Takayasu′s arteritis-pulmonary artery involvement, TA-PAI)是一种累及肺动脉及其分支的慢性进行性炎性疾病, 多数患者早期表现为发热、呼吸困难、胸痛等非特异性呼吸系统症状, 误诊率较高。目前TA-PAI的诊断主... 详细信息

大动脉炎肺动脉受累(Takayasu′s arteritis-pulmonary artery involvement, TA-PAI)是一种累及肺动脉及其分支的慢性进行性炎性疾病, 多数患者早期表现为发热、呼吸困难、胸痛等非特异性呼吸系统症状, 误诊率较高。目前TA-PAI的诊断主要依据大动脉炎的诊断标准及肺动脉受累的影像学证据, 但肺动脉受累未被纳入常用的大动脉炎诊断标准, 导致TA-PAI尤其是孤立性肺动脉受累诊断率可能被严重低估。本文报道1例26岁的女性患者, 反复胸痛伴发热, 外院诊断为"肺炎", 治疗4个月未见明显好转, 后因咯血发作于我院就诊, 最终确诊为大动脉炎肺动脉受累, 予激素、免疫抑制剂以及肺血管介入治疗后病情稳定。通过分析该病例的临床特点及诊疗思路, 并复习相关文献, 提高临床医生对大动脉炎肺动脉受累的认识。

关键词：大动脉炎呼吸系统症状血管介入治疗诊断标准诊疗思路临床医生胸痛呼吸困难

基于PD-1/PD-L1信号通路探讨麦门冬汤对特发性肺纤维化小鼠的影响

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中成药 2024年第2期46卷 437-443页

作者：徐梦真刘传国巩丽丽陈海红王栋朱庆均山东中医药大学中医药创新研究院山东济南250355 山东中医药大学实验中心山东济南250355 教育部中医药经典理论研究重点实验室山东济南250355 山东中医药大学药学院山东济南250355

目的探讨麦门冬汤对博来霉素(BLM)诱导的特发性肺纤维化(IPF)小鼠的影响,并探究其对免疫调控的作用。方法气管滴注BLM建立IPF小鼠模型,将小鼠随机分为对照组、模型组、吡非尼酮组(0.3 g/kg)及麦门冬汤高、中、低剂量组(18、9、4.5 g/kg... 详细信息

目的探讨麦门冬汤对博来霉素(BLM)诱导的特发性肺纤维化(IPF)小鼠的影响,并探究其对免疫调控的作用。方法气管滴注BLM建立IPF小鼠模型,将小鼠随机分为对照组、模型组、吡非尼酮组(0.3 g/kg)及麦门冬汤高、中、低剂量组(18、9、4.5 g/kg)。采用HE和Masson染色、ELISA法、流式细胞术和免疫组织化学法检测小鼠肺组织病理变化、Collagen I、HYP及TGF-β1水平、血浆中PD-1^(+)CD4^(+)T细胞比例、肺组织p-STAT3、PD-1、PD-L1和IL-17A表达。结果与对照组比较,模型组小鼠肺系数升高(P<0.01),肺组织中大量炎性细胞浸润、胶原纤维沉积,肺纤维化评分升高(P<0.01),Collagen I、HYP、TGF-β1水平增加(P<0.01),血浆中PD-1^(+)CD4^(+)T细胞比例增加(P<0.01),肺组织p-STAT3、PD-1、PD-L1、IL-17A表达升高(P<0.01);与模型组比较,麦门冬汤组小鼠肺系数降低(P<0.05),肺组织炎性细胞浸润和胶原纤维沉积减少,肺纤维化评分降低(P<0.05),Collagen I、HYP、TGF-β1水平减少(P<0.05),血浆中PD-1^(+)CD4^(+)T细胞比例减少(P<0.05),肺组织p-STAT3、PD-1、PD-L1、IL-17A表达降低(P<0.05)。结论麦门冬汤可减少细胞外基质(ECM)沉积,延缓IPF进程,其机制可能与抑制STAT3/PD-1/PD-L1免疫调控信号通路有关。

关键词：麦门冬汤特发性肺纤维化博来霉素免疫调控 STAT3/PD-1/PD-L1信号通路