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Hydrothermal and sulfur aging of CeTi/CeWTi catalysts for selective catalytic reduction of NOx with NH3

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Journal of Rare Earths 2019年第8期37卷 829-836,I0002页

作者： Lei Chen Ding wang Jiadao wang Duan weng Li Cao State Key Laboratory of Tribology School of Mechanical EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Advanced Materials of Ministry of Education School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

The CeO2-TiO2(CeTi)and CeO2/WO3-TiO2(CeWTi)catalysts were prepared by sol-gel *** asprepared catalysts were hydrothermally treated at 760℃for 48 h in air containing 10 vol%H2O to obtain the hydrothermal aged *** sulfur aged catalysts were treated at 400℃with 100 ppm SO2,10%water vapor,air balance for 48 h and *** powder X-ray diffraction(XRD)and Raman results indicate that the crystallization of hydrothermal aged catalysts is more serious than sulfur aged *** addition,tungsten species can stabilize the CeTi catalyst from grain *** to the results of in situ diffuse reflectance infrared Fourier transform spectra(DRIFTS),temperatureprogrammed desorption of ammonia(NH3-TPD),H2 temperature-programmed reduction(H2-TPR)and ammonia oxidation,the aging process leads to loss of surface area,redox properties,surface acidities and surface ceria concentration,especially for the hyd rothermal *** NH3-NO/NO2 SCR perfo rmances of sulfur aged catalysts are better than that of hydrothermal aged *** with CeTi catalyst,the addition of tungsten inhibits the crystallization of *** that more acid sites and active sites are *** is also the reason why tungsten addition improves the NH3-NO/NO2 SCR performance of CeTi catalyst.

关键词： CeWTi catalyst Crystallization Surface acidity Redox property SCR activity Rare earths

考虑平均应力影响的7075-T651铝合金疲劳性能研究

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机械强度 2024年第2期46卷 446-452页

作者：俞俊王宇李海芳翁硕何小田赵礼辉上海理工大学机械工程学院上海200093 北汽福田汽车股份有限公司时代领航卡车工厂潍坊262103 机械工业汽车机械零部件强度与可靠性评价重点实验室上海200093 上海市新能源汽车可靠性评价公共技术平台上海200093

研究了平均应力效应对7075-T651铝合金疲劳性能的影响,选取了R=0.5、0.3、0.1和-0.1四组应力比进行疲劳试验。结果表明,同一应力比下,随着峰值应力水平的增加,疲劳寿命逐渐降低;而同一峰值应力水平下,随着应力比的提高,疲劳寿命则呈现... 详细信息

研究了平均应力效应对7075-T651铝合金疲劳性能的影响,选取了R=0.5、0.3、0.1和-0.1四组应力比进行疲劳试验。结果表明,同一应力比下,随着峰值应力水平的增加,疲劳寿命逐渐降低;而同一峰值应力水平下,随着应力比的提高,疲劳寿命则呈现出逐渐升高的趋势。同时,使用扫描电子显微镜(Scanning Electron Microscopy,SEM)观察疲劳断口形貌发现,在峰值应力相同的情况下,裂纹萌生及扩展区的扇形面积随平均应力的增大而增大。最后,基于7075-T651铝合金疲劳实验结果,提出了一种考虑S-N-R的改进型预测模型,结果对比显示相较于其他模型,此模型在一定程度上对7075-T651铝合金具有更好的疲劳寿命预测效果。

关键词： 7075-T651铝合金平均应力疲劳寿命断口形貌预测模型

Changes in nerve microcirculation following peripheral nerve compression

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Neural Regeneration Research 2013年第11期8卷 1041-1047页

作者： Yueming Gao Changshui weng Xinglin wang Rehabilitation Medicine Center General Hospital of Chinese PLA Department of Rehabilitation Medicine South Building General Hospital of Chinese PLA

Following peripheral nerve compression, peripheral nerve microcirculation plays important roles in regulating the nerve microenvironment and neurotrophic substances, supplying blood and oxygen and maintaining neural conduction and axonal transport. This paper has retrospectively analyzed the articles published in the past 10 years that addressed the relationship between peripheral nerve compression and changes in intraneural microcirculation. In addition, we describe changes in different peripheral nerves, with the aim of providing help for further studies in peripheral nerve microcirculation and understanding its protective mechanism, and exploring new clinical methods for treating peripheral nerve compression from the perspective of neural microcirculation.

关键词： neural regeneration peripheral nerve injury peripheral nerve microcirculation nerve compression nerve blood flow sciatic nerve grants-supported paper neuroregeneration

基于CNN-Transformer的自动泊车车位感知算法

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汽车技术 2024年第8期 1-6页

作者：王玉龙翁茂楠黄辉覃小艺广州汽车集团股份有限公司汽车工程研究院广州510641 湖南大学汽车车身先进设计制造国家重点实验室长沙410082

为提高自动泊车成功率及准确性,首先基于卷积神经网络(CNN)模型对输入图像进行特征提取,然后利用Transfomer模型的“编码-解码”机制对CNN提取到的图像特征平铺后进行计算推理,通过前馈神经网络得到目标预测结果,最后基于180°广角鱼眼... 详细信息

为提高自动泊车成功率及准确性,首先基于卷积神经网络(CNN)模型对输入图像进行特征提取,然后利用Transfomer模型的“编码-解码”机制对CNN提取到的图像特征平铺后进行计算推理,通过前馈神经网络得到目标预测结果,最后基于180°广角鱼眼图像进行推理识别,车位角中心点和空车位入口中心点均采用二维坐标表示,降低了输出信息的冗余,优化了模型结构。测试结果表明,该算法能够较好地适应不同车位线划线方式和不同的自然环境,目标感知的召回率达到98%,车位角中心点定位平均误差小于3 cm,满足泊车系统对车位感知的鲁棒性、实时性和准确性要求。

关键词：自动泊车车位检测视觉增强卷积神经网络 Transformer

Influence of the continuing COVID-19 epidemic on sleep quality and psychological status of healthcare workers in private institutions

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World Journal of Psychiatry 2024年第10期14卷 1495-1505页

作者： Man-In Ho Zhe-Hao Wu Yu-Ying Chen weng-Io Leong Jue wang Hua Zhou Zi-Tuo Wu Ying-Qi Mao Jia-An Du Yi Zheng Yi Yu Paulo Do Lago Comandante Li-Li Yu Qi-Biao Wu Faculty of Chinese Medicine Medical Sciences DivisionMacao University of Science and TechnologyMacao 999078China Department of Child Rehabilitation Children Health CareJieyang Women Infant Health Care HospitalJieyang 522000Guangdong ProvinceChina Macao Association for Analytical Psychology Macao 999078China The State Key Laboratory of Quality Research in Chinese Medicine Macao University of Science and TechnologyMacao 999078China State Key Laboratory of Dampness Syndrome of Chinese Medicine The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510006Guangdong ProvinceChina Guangdong Provincial Hospital of Chinese Medicine Guangdong Provincial Academy of Chinese Medical SciencesGuangzhou 511400Guangdong ProvinceChina Chinese Medicine Guangdong Laboratory(Hengqin Laboratory) Guangdong-Macao In-Depth Cooperation Zone in HengqinHengqin 519000Guangdong ProvinceChina University Hospital Macao University of Science and TechnologyMacao 999078China Department of Rehabilitation The First Affiliated Hospital of Zhejiang Chinese Medical University(Zhejiang Provincial Hospital of Chinese Medicine)Hangzhou 310006Zhejiang ProvinceChina Department of Clinical Nutrition The Second Affiliated Hospital of Zhejiang Chinese Medical UniversityXinhua Hospital of Zhejiang ProvinceHangzhou 310000Zhejiang ProvinceChina Associação dos Investigadores Praticantes e Promotores da Medicina Chinesa de MacaoMacao 999078China Zhuhai MUST Science and Technology Research Institute Macao University of Science and TechnologyZhuhai 519099Guangdong ProvinceChina Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health Guangdong University of TechnologyGuangzhou 510000Guangdong ProvinceChina

BACKGROUND On January 22,2020,Macao reported its first case of coronavirus disease 2019(COVID-19)*** August 2021,the situation had escalated into a crisis of community *** response,the government launched a recruitment campaign seeking assistance and services of healthcare workers(HCWs)from the private sector throughout *** participants faced concerns about their own health and that of their families,as well as the responsibility of maintaining public health and *** study aims to determine whether the ongoing epidemic has caused them physical and psychological *** To examine the influence of COVID-19 on the sleep quality and psychological status of HCWs in private institutions in Macao during the *** Data were collected from December 2020 to January *** consecutive surveys were *** Pittsburgh Sleep Quality Index(PSQI)scale,Self-Rating Anxiety Scale(SAS),and Self-Rating Depression Scale(SDS)were employed as investigation *** In the first-stage survey,32%of HCWs experienced a sleep disorder,compared to 28.45%in the second-stage survey.A total of 31.25%of HCWs in the first-stage survey and 28.03%in the second had varying degrees of anxiety.A total of 50.00%of HCWs in the first-stage survey and 50.63%in the second experienced varying degrees of *** difference in PSQI scores,SAS scores,or SDS scores were observed between the two surveys,indicating that the COVID-19 epidemic influenced the sleep quality and psychological status of *** negative influence persisted over both periods but did not increase remarkably for more than a ***,a positive correlation was observed between the PSQI,SAS,and SDS scores(r=0.428-0.775,P<0.01),indicating that when one of these states deteriorated,the other two tended to deteriorate as *** The sleep quality,anxiety,and depression of HCWs in private institution in Macao were affected by the COVID-19 *** these fac

关键词： COVID-19 Healthcare workers Sleep quality Anxiety Depression Psychological status

归黄固齿方治疗慢性牙周炎患者临床疗效及对龈沟液IL-1β、MMP-13水平的影响

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湖北中医药大学学报 2024年第2期26卷 34-37页

作者：王娇陈成翁国建江苏省南京市浦口区中医院江苏南京211800

目的观察归黄固齿方治疗慢性牙周炎疗效及对龈沟液白细胞介素-1β(IL-1β)、基质金属蛋白酶-13(MMP-13)水平的影响。方法将我院90例慢性牙周炎(胃火炽盛证)患者按照随机数表法分为对照组与治疗组各45例。对照组在基础治疗上采用罗红... 详细信息

目的观察归黄固齿方治疗慢性牙周炎疗效及对龈沟液白细胞介素-1β(IL-1β)、基质金属蛋白酶-13(MMP-13)水平的影响。方法将我院90例慢性牙周炎(胃火炽盛证)患者按照随机数表法分为对照组与治疗组各45例。对照组在基础治疗上采用罗红霉素片、替硝唑片治疗,治疗组在对照组治疗基础上采用归黄固齿方辅助治疗。比较两组临床疗效及治疗前后中医证候积分,龈沟液实验室指标IL-1β、MMP-13,牙周临床指标牙周袋深度(PD)、龈沟出血指数(SBI)、牙龈指数(GI),骨代谢指标碱性磷酸酶(ALP)、骨钙素(OC)、Ⅰ型前胶原N端前肽(PINP)。结果治疗后,治疗组总有效率高于对照组(P<0.05);两组中医证候积分、IL-1β、MMP-13、PD、SBI、GI、ALP、OC均较治疗前降低,PINP较治疗前升高,治疗组上述指标与对照组比较差异有统计学意义(P<0.05)。结论归黄固齿方治疗慢性牙周炎患者疗效良好,能够降低IL-1β、MMP-13水平,改善牙周健康和骨代谢指标,临床推荐应用。

关键词：慢性牙周炎归黄固齿方龈沟液白细胞介素-1β 基质金属蛋白酶-13

Effects of tungsten oxide on the activity and thermal stability of a sulfate-derived titania supported platinum catalyst for propane oxidation

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Journal of Environmental Sciences 2012年第3期24卷 458-463页

作者： Xiaodong Wu Zhou Zhou Duan weng Bin wang Laboratory of Advanced Materials Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

A Pt/WO3/TiO2 catalyst for propane oxidation was prepared by a stepwise wet impregnation method, and was aged at 800°C for 5 hr. Compared to the sulfate-derived titania supported catalyst, the introduction of tungsten oxide as stable Br nsted acid sites led to the formation of more metallic platinum active sites at the Pt/WO3 interface. The dissociation of surface intermediates for propane oxidation was promoted on the WO3-modified catalyst. This, as well as the inhibition effects of tungsten oxide on the sintering of anatase and the phase transformation to rutile, resulting in a high activity and thermal stability for the Pt/WO3/TiO2 catalyst.

关键词： platinum acidic support propane oxidation infrared spectra ageing

基于MODIS遥感数据的福建植被生产力时空分布与干旱响应分析

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生态环境学报 2024年第6期33卷 841-852页

作者：李新妹吴作航王震山翁升恒孙朝锋关辉王宏福建省灾害天气重点实验室/中国气象局海峡灾害天气重点开放实验室福建福州350007 福建省福州市气象局福建福州350008 福建省气象科学研究所福建福州350007 民航西南空管局气象中心四川成都610202 福建省气象服务中心福建福州350007 民航福建空中交通管理分局福建福州350209 厦门市海峡气象开放重点实验室福建厦门361012

全球升温导致干旱发生的范围和强度增加,但干旱对生态系统碳循环的影响还不明确。基于MODIS遥感数据,采用Sen趋势分析及Mann-Kendall检验、Pearson相关性分析等方法,通过干旱对植被生产力标准化异常的影响等信号,分析了2001-2021年福建... 详细信息

全球升温导致干旱发生的范围和强度增加,但干旱对生态系统碳循环的影响还不明确。基于MODIS遥感数据,采用Sen趋势分析及Mann-Kendall检验、Pearson相关性分析等方法,通过干旱对植被生产力标准化异常的影响等信号,分析了2001-2021年福建省植被总初级生产力(Gross Primary Productivity,GPP)、净初级生产力(Net Primary Productivity,NPP)的时空变化特征与干旱对其的影响及累积/滞后效应。结果表明,1)空间上,福建省植被GPP、NPP多年平均空间分布均呈现“东南高,西北低”的特征,区域平均差异分别为37.4%、65.1%;近21年以来,有近80.8%的区域GPP呈现增长趋势,主要分布在福建省南部、东南部少部分地区,主要指被类型为农田,多为热带经济水果种植的集中区域;另外,超过59.7%的区域NPP呈现下降趋势,主要出现在福建省中部及内陆山区的常绿阔叶林地和稀树草原。2)时间上,植被GPP年际波动明显,总体呈现弱增长趋势[4.86 g∙m^(−2)∙a^(−2)(以C计,下同),p=0.130],空间上,6.7%的区域年增速显著超过15 g∙m^(−2)∙a^(−2);而NPP年际变化总体呈现弱下降趋势(−1.05 g∙m^(−2)∙a^(−2),p=0.396),4.9%的区域年降速显著超过6 g∙m^(−2)∙a^(−2)。3)研究时段内福建省出现的干旱过程主要以中等干旱为主(52.5%),其次是轻旱(34.0%)。植被GPP、NPP年标准化异常指数与干旱指数(SPEI)存在显著的负相关关系,相关系数分别为−0.624(p=0.002)、−0.531(p=0.013),说明旱情越严重的年份GPP、NPP越高,而旱情较轻或无旱的年份GPP、NPP较低。干旱对GPP最明显的影响主要发生在干旱当月,累积/滞后效应时间较短;干旱事件对GPP的影响是“先增-后缓-再减”,干旱发生初期GPP呈增加趋势,而随着干旱的持续发展,GPP的增加幅度明显减弱,甚至出现负效果。

关键词：植被生产力时空分布标准化异常指数累积/滞后效应福建省

Insights into efficient transition metal-nitrogen/carbon oxygen reduction electrocatalysts

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Journal of Energy Chemistry 2021年第5期30卷 470-485页

作者： Hao-Yu wang Chen-Chen weng Zhong-Yong Yuan National Institute for Advanced Materials School of Materials Science and EngineeringNankai UniversityTianjin 300350China

It is of vital importance to accelerate the sluggish oxygen reduction reaction(ORR)process at the cathode with earth-abundant metal-based catalysts for the commercialization of low-temperature polymer electrolyte membrane fuel *** consideration of high catalytic activity,long-term stability and low cost of potential ORR electrocatalysts,transition metal species have attracted much interest and transition metal-nitrogen-carbon(M-N/C,M=Fe,Co,Ni,Mn,etc.)catalysts have been widely considered as the most promising non-precious metal catalysts for ***,the fundamental understanding of ORR catalytic mechanism and the identification of active centers are briefly introduced,and then different M-N/C catalysts classified by precursors with the strategies for design and optimization are *** challenges and possible opportunity for future development of high-performance ORR catalysts are finally proposed.

关键词： Electrocatalysis Oxygen reduction reaction Metal-nitrogen/carbon Fuel cell