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Sb改性对Mn-Ce/TiO_(2)低温SCR催化剂性能的影响

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中国电机工程学报 2022年第12期42卷 4487-4497页

作者：闫东杰郭通陈兆辉玉亚陕西省环境工程重点实验室(西安建筑科技大学) 陕西省西安市710055

采用浸渍法分别制备Mn/TiO_(2)、Mn-Ce/TiO_(2)、Mn-CeSb/TiO_(2) 3种催化剂,考察了3种催化剂在低温90~220℃之间的活性和选择性,并利用BET (Brunauer-Emmett-Teller,BET)比表面积分析、扫描电镜(scanning electron microscope,SEM)、X射线衍射(X-ray diffraction,XRD)、傅里叶变换红外光谱(Fourier transform infrared spectroscopy,FT-IR)、X光电子能谱(X-ray photoelectron spectroscopy,XPS)、H2-程序升温还原(H2-temperature-programmed reduction,H2-TPR)和NH3-程序升温脱附(NH3-temperatureprogrammed desorption,NH3-TPD)对3种不同的催化剂样品进行了表征,分析影响选择性催化还原(selective catalytic reduction,SCR)活性的原因。当Sb/Mn=0.2时,Mn-Ce-Sb/TiO_(2)催化剂具有最佳活性,NOx转化率在120℃时达到94%,150℃时的NOx去除率达到98%,锑的掺杂同样提高了Mn-Ce/TiO_(2)催化剂的氮气选择性。BET和XRD表征结果发现Sb改性增大催化剂的比表面积,降低锰氧化物的结晶度,TPD和TPR发现Sb改性使得低温下的氧化还原能力增强,但对酸性位点没有大的影响。XPS结果表明锑的掺杂可以提高Mn-Ce-Sb40.2/TiO 2催化剂表面的吸附氧和Ce^(+)/Ce^(3+),这使得Ce^(4+)和Ce^(3+)之间的氧气储存和释放增强,同时化学吸附氧含量的增高,使得催化剂表面的氧迁移率提高,可以更好的促进NO转化为NO_(2)通过“快速SCR反应”提高反应活性。还检测到Sb的引入可以提高Mn^(4+)的含量,这同样使得NO去除率提高。探究Sb掺杂对催化剂抗硫性实验发现引入Sb后可以提高催化剂在低温下对SO_(2)的耐受性,150℃下反应8h其NOx转化率从98%降到81%,而且在停止通入SO_(2)后活性可恢复到97%。

关键词：低温选择性催化还原 Sb改性 Mn-Ce/TiO_(2) 抗硫性

Influence of various volute designs on volute overall performance

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Journal of Thermal Science 2010年第6期19卷 505-513页

作者： Xiaoqing Qiang Jinfang Teng zhaohui Du School of Mechanical Engineering Shanghai Jiao Tong University Shanghai China School of Aeronautics and Astronautics Shanghai Jiao Tong University Shanghai China

This paper discusses the influence of various volute designs on volute overall performance for a certain centrifugal compressor with both vaned and vaneless diffuser. Firstly, based on a free vortex flow pattern and the assumption of a circumferentially uniform flow at the design condition, a corrected method for volute design is adopted. By means of this method, corresponding to five geometric parameters affecting the volute overall performance, ten volute cases are designed. Secondly, the numerical simulation is employed and the detailed flow field and losses in different volutes with different geometric parameters are analyzed. The numerical investigation reveals that in all of the five geometric parameters, the radial location of the cross-section has the strongest influence on the performance of the volute. The non-uniform volute inlet formed by the upward vaned diffuser outlet flow is another important factor. Finally a relatively better value of D4/D2 is concluded.

关键词：蜗壳设计性能影响几何参数数值模拟叶片扩压器流动模式修正方法径向位置

Association between hemoglobin glycation index and 5-year major adverse cardiovascular events:the REACTION cohort study

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Chinese Medical Journal 2023年第20期136卷 2468-2475页

作者： Yuhan Wang Hongzhou Liu Xiaodong Hu Anping Wang Anning Wang Shaoyang Kang Lingjing Zhang Weijun Gu Jingtao Dou Yiming Mu Kang Chen Weiqing Wang zhaohui Lyu Department of Endocrinology The First Medical CenterChinese PLA General HospitalBeijing 100853China Department of Endocrinology The Second Medical Center and National Clinical Research Center for Geriatric DiseasesChinese PLA General HospitalBeijing 100853China Department of Endocrinology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai Institute of Endocrine and Metabolic DiseasesShanghai 200025China

Background:The hemoglobin glycation index(HGI)was developed to quantify glucose metabolism and individual differences and proved to be a robust measure of individual glycosylated hemoglobin(HbA1c)bias.Here,we aimed to explore the relationship between different HGIs and the risk of 5-year major adverse cardiovascular events(MACEs)by performing a large multicenter cohort study in China.Methods:A total of 9791 subjects from the Risk Evaluation of Cancers in Chinese Diabetic Individuals:a Longitudinal Study(the REACTION study)were divided into five subgroups(Q1-Q5)with the HGI quantiles(≤5th,>5th and≤33.3th,>33.3th and≤66.7th,>66.7th and≤95th,and>95th percentile).A multivariate logistic regression model constructed by the restricted cubic spline method was used to evaluate the relationship between the HGI and the 5-year MACE risk.Subgroup analysis between the HGI and covariates were explored to detect differences among the five subgroups.Results:The total 5-year MACE rate in the nationwide cohort was 6.87%(673/9791).Restricted cubic spline analysis suggested a U-shaped correlation between the HGI values and MACE risk after adjustment for cardiovascular risk factors(x^(2)=29.5,P0.82 showed odds ratios(ORs)for MACE of 1.471(95%confidence interval[CI],1.027-2.069)and 2.222(95%CI,1.641-3.026)compared to subjects with HGIs of>-0.75 and≤-0.20.In the subgroup with non-coronary heart disease,the risk of MACE was significantly higher in subjects with HGIs≤-0.75(OR,1.540[1.039-2.234];P=0.027)and>0.82(OR,2.022[1.392-2.890];P0.82 after adjustment for potential confounders.Conclusions:We found a U-shaped correlation between the HGI values and the risk of 5-year MACE.Both low and high HGIs were associated with an increased risk of MACE.Therefore,the HGI may predict the 5-year MACE risk.

关键词： Diabetes mellitus Hemoglobin glycation index Major adverse cardiovascular events Blood glucose Metabolism Ushaped correlation

The theory of critical flicker fusion frequency and its application in cataracts

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Advances in Ophthalmology Practice and Research 2023年第1期3卷 29-32页

作者： Guangcan Xu Junxia Fu Haolan Qi Linyu Li Wenqian Chen Yi Gao Tianju Ma Zi Ye zhaohui Li School of Medicine Nankai UniversityTianjinChina Department of Ophthalmology The Third Medical CenterThe Chinese People's Liberation Army General HospitalBeijingChina Department of Ophthalmology Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghaiChina The Chinese People's Liberation Army Medical School BeijingChina

Background:Due to media opacity,it is usually difficult to accurately evaluate the postoperative visual acuity in cataracts patients.As a small and portable tool,the critical flicker fusion frequency(CFF)device reflects the temporal resolution of visual function and has been widely used in clinical research.However,poor understanding of the technique and equipment limitations have restricted its clinical application in China.Main text:There was a decrease in the CFF value in various ophthalmic diseases,indicating that the CFF is sensitive to detect visual functional changes.A number of studies have shown that the CFF test can accurately distinguish patients with simple cataracts from those with cataracts combined with fundus disease,and,as a visual test,it can more accurately predict postoperative visual acuity without being affected by media opacity.This study comprehensive reviews the basic principles of CFF and its application in ophthalmology,especially in cataracts.Conclusions:As one of the tools for dynamic visual function detection,the CFF test could help doctors to assess the possible presence of fundus disease in cataracts patients,especially in eyes with dense cataracts,and more precisely provide a reasonable visual prognosis than other available visual tests.

关键词： Critical flicker fusion frequency Cataracts Review

民族、本土、现代与转型——冈仓天心与柳宗悦思想的启示

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天津美术学院学报 2022年第5期 33-40页

作者：仝朝晖北京建筑大学清华大学

近现代日本社会中,冈仓天心倡导的新日本画运动和柳宗悦倡导的民艺运动,形成鲜明对比。“日本画”“民艺”都是近代日本社会在构建民族国家、彰显民族文化个性的话语背景下而出现的新词汇。在发扬民族文化是否要借鉴西方现代化的立场上... 详细信息

近现代日本社会中,冈仓天心倡导的新日本画运动和柳宗悦倡导的民艺运动,形成鲜明对比。“日本画”“民艺”都是近代日本社会在构建民族国家、彰显民族文化个性的话语背景下而出现的新词汇。在发扬民族文化是否要借鉴西方现代化的立场上,冈仓天心和柳宗悦“同道不同途”。两人思想提供的启示就在于,它呈现出一个哲学意义的“价值”分界:传统文化研究保护与传统文化现代转型,两者“功能”可以互相补充,但“价值”不能代替。中国当代进行非遗保护与民艺研究,包括民艺的现代转型实践,要注意到中国式的角度。

关键词：日本画民艺民众之美文化个性民族根性

Intelligent control of mode-locked femtosecond pulses by time-stretch-assisted real-time spectral analysis

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Light(Science & Applications) 2020年第1期9卷 1881-1888页

作者： Guoqing Pu Lilin Yi Li Zhang Chao Luo zhaohui Li Weisheng Hu State Key Lab of Advanced Communication Systems and Networks Shanghai Institute for Advanced Communication and Data ScienceShanghai Jiao Tong UniversityShanghai 200240China Sun Yat-sen University/Southern Marine Science and Engineering Guangdong Laboratory ZhuhaiChina

Mode-locked fiber lasers based on nonlinear polarization evolution can generate femtosecond pulses with different pulse widths and rich spectral distributions for versatile applications through polarization tuning.However,a precise and repeatable location of a specific pulsation regime is extremely challenging.Here,by using fast spectral analysis based on a time-stretched dispersion Fourier transform as the spectral discrimination criterion,along with an intelligent polarization search algorithm,for the first time,we achieved real-time control of the spectral width and shape of mode-locked femtosecond pulses;the spectral width can be tuned from 10 to 40 nm with a resolution of ~1.47 nm,and the spectral shape can be programmed to be hyperbolic secant or triangular.Furthermore,we reveal the complex,repeatable transition dynamics of the spectrum broadening of femtosecond pulses,including five middle phases,which provides deep insight into ultrashort pulse formation that cannot be observed with traditional mode-locked lasers.

关键词： polarization tuning spectral

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防治糖尿病性视网膜病变的生物靶标研究进展

中药药理与临床 2023年第3期39卷 111-116页

作者：金童徐朝晖王海颖上海中医药大学中药学院上海201203 上海中医药大学创新中药研究院上海201203

糖尿病视网膜病变(Diabetic Retinopathy,DR)是糖尿病最常见的微血管并发症,主要病因是糖尿病导致的高血糖所引起的炎症、氧化应激、晚期糖基化产物增加、血管内皮生长因子(VEGF)含量提高等使得视网膜通透性增加,视网膜血流动力学因此... 详细信息

糖尿病视网膜病变(Diabetic Retinopathy,DR)是糖尿病最常见的微血管并发症,主要病因是糖尿病导致的高血糖所引起的炎症、氧化应激、晚期糖基化产物增加、血管内皮生长因子(VEGF)含量提高等使得视网膜通透性增加,视网膜血流动力学因此发生改变,最终导致视网膜渗漏,直至失明,临床症状表现为早期视力下降,甚至会发展至失明,严重影响糖尿病患者的日常生活。大量研究表明,寻找病程进展中的关键通路的关键信号因子作为治疗DR的生物靶标,包括炎症反应、氧化应激、晚期糖基化、蛋白激酶C(PKC)通路等,对于研发治疗药物具有促进作用。本文针对DR病程发展过程中的相关生物靶点的研究进展进行综述,为防治DR的药物研发提供理论支撑。

关键词：糖尿病性视网膜病变生物靶标氧化应激炎症肿瘤坏死因子

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西安鄠邑什王村村名由来

寻根 2022年第3期 99-103页

作者：仝朝晖北京建筑大学

西安市鄠邑区原名县、户县。当地的苍游镇什王村是国家级“非遗”——北乡迎城隍民俗的发祥地之一。民间传说城隍爷(纪信将军)是县北纪家庄人。纪家庄相传在今什王村东北,已无存,有说在20世纪50年代前这里还可以看到纪家庄废墟。而城隍... 详细信息

西安市鄠邑区原名县、户县。当地的苍游镇什王村是国家级“非遗”——北乡迎城隍民俗的发祥地之一。民间传说城隍爷(纪信将军)是县北纪家庄人。纪家庄相传在今什王村东北,已无存,有说在20世纪50年代前这里还可以看到纪家庄废墟。而城隍婆(纪信夫人)据称就是什王村人。因此当地遗存一个有意思的民俗:北乡迎城隍只有轮流到了什王村,城隍婆轿子是走在城隍爷的前面,算是特别的礼遇。

关键词：城隍纪信北乡民间传说民俗发祥地

内镜下序贯套扎治疗食管胃伴十二指肠静脉曲张1例报告

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临床肝胆病杂志 2023年第3期39卷 637-639页

作者：文皓何朝晖蒋彤石国庆遵义医科大学第五附属(珠海)医院消化内科广东珠海519100 遵义医科大学附属医院消化内科贵州遵义563000

门静脉高压异位静脉曲张临床上较少见,在肝硬化静脉曲张破裂出血中,异位静脉曲张占2%~5%,其中最常见的发生在十二指肠,约17%,但是病死率却高达40%[1]。目前尚无指南推荐治疗十二指肠静脉曲张的方法,尤其是食管胃静脉曲张合并十二指肠静... 详细信息

门静脉高压异位静脉曲张临床上较少见,在肝硬化静脉曲张破裂出血中,异位静脉曲张占2%~5%,其中最常见的发生在十二指肠,约17%,但是病死率却高达40%[1]。目前尚无指南推荐治疗十二指肠静脉曲张的方法,尤其是食管胃静脉曲张合并十二指肠静脉曲张时如何开展治疗,尚未见具体病例报道。本文对1例食管、胃、十二指肠静脉曲张患者采用内镜下序贯套扎治疗,静脉曲张均一次性根除,取得了很好的疗效和安全性,报道如下。

关键词：食管和胃静脉曲张内窥镜十二指肠