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A building-based data capture and data mining technique for air quality assessment

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Frontiers of Environmental Science & Engineering 2011年第4期5卷 543-551页

作者： Ni SHENg U wa TANg Faculty of Management and Administration Macao University of Science and TechnologyMacaoChina Department of Civil and Environmental Engineering University of MacaoMacaoChina Dirccao dos Servicos de Proteccao Ambiental MacaoChina

Recently,a building-based air quality model system which can predict air quality in front of individual buildings along both sides of a road has been *** the Macao Peninsula as a case study,this paper shows the advantages of building-based model system in data capture and data *** with the traditional grid-based model systems with input/output spatial resolutions of 1-2 km,the building-based approach can extract the street configuration and traffic data building by building and therefore,can capture the complex spatial variation of traffic emission,urban geometry,and air *** non-homogeneous distribution of air pollution in the Macao Peninsula was modeled in a highspatial resolution of 319 receptors·km^(-2).The spatial relationship among air quality,traffic flow,and urban geometry in the historic urban area is *** study shows that the building-based approach may open an innovative methodology in data mining of urban spatial data for environmental *** results are particularly useful to urban planners when they need to consider the influences of urban form on street environment.

关键词： traffic air pollution spatial distribution high resolution geographic information system

Copper-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides withβ-trifluoromethyl-substituted alkenyl heteroarenes

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Science China Chemistry 2023年第11期66卷 3193-3204页

作者： Xiang Cheng xin Chang Yuhong Yang Zongpeng Zhang Jing Li Yipu Li wenxiao Zhao Lung wa Chung Huailong Teng Xiu-Qin Dong Chun-Jiang wa.g College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryShanghai 230021China Shenzhen grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China College of Science Huazhong Agricultural UniversityWuhan 430070China

Copper-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides andβ-trifluoromethyl-substituted alkenyl heteroarenes was developed for the first time.A wide range of enantioenriched pyrrolidines containing both heteroarenes and trifluoromethyl group with multiple stereogenic centers could be readily accessible by this method with good to high yields and excellent levels of both stereo-and regioselectivity(up to 99%yield,>20:1 rr,>20:1 dr,and up to 95%ee).Notably,substratecontrolled umpolung-type dipolar cycloaddition was also disclosed in this protocol to achieve regiodivergent synthesis withα-aryl substituted aldimine esters as the dipole *** DFT studies were conducted to explore the origin of the stereo-and regioselectivity of this 1,3-dipolar cycloaddition,and suggest that copper(Ⅱ)salt utilized in this catalytic system could be reduced in-situ to the active copper(Ⅰ)species and might be responsible for the observed high stereo-and regioselectivity.

关键词： asymmetric catalysis 1 3-dipolar cycloaddition chiral pyrrolidines heteroarene trifluoromethyl group

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REMAPPINg DIgITAL OPERATIONS iClick is promoting big data technologies among companies to facilitate high-quality economic growth

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China Report ASEAN 2021年第5期6卷 48-49页

作者： xin Lida Long wa 不详

As traditional retail was pummeled by the COVID-19 pandemic,retailers were forced to accelerate integration of online and offline *** Jian,CEO of iClick Interactive,a solution provider for digital business operations,has been urging retail companies,service providers,and business platforms to keep pace with the transformation as COVID-19 prevention and control measures become normalized and profound changes take place in business operations and consumer *** quality of the growth of the digital economy is improving rapidly,and business activities including transactions and customer communication with sellers have transformed into data records.

关键词： companies operations prevention

嗜热链球菌grx02化学限定增殖培养基及变温培养策略的研究

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中国乳品工业 2024年第2期52卷 5-11,19页

作者：彭奎耀关成冉瓦云超顾瑞霞扬州大学江苏省乳品生物技术与安全控制重点实验室江苏扬州225000

文章研究了能够促进嗜热链球菌grx02生长的化学限定培养基成分、浓度及其变温培养方法。通过单一成分扣除实验确定化学限定培养基的碳源、氨基酸、维生素矿物质等营养成分的组成,进一步通过单因素实验,对化学限定培养基组分浓度、变温... 详细信息

文章研究了能够促进嗜热链球菌grx02生长的化学限定培养基成分、浓度及其变温培养方法。通过单一成分扣除实验确定化学限定培养基的碳源、氨基酸、维生素矿物质等营养成分的组成,进一步通过单因素实验,对化学限定培养基组分浓度、变温培养方法进行优化,以提高嗜热链球菌grx02的活菌数。结果表明,嗜热链球菌grx02化学限定增殖培养基由1种碳水化合物、16种氨基酸、6种维生素、3种矿物质、4种无机盐、2种有机盐组成;培养初始温度、延滞末期及对数末期温度分别为39、37、39℃。最终嗜热链球菌grx02生物量达到1.40,较优化前提高了1.63倍,活菌数达到9.04 log CFU/mL。可为嗜热链球菌生产及其代谢与功能研究提供参考。

关键词：嗜热链球菌化学限定培养基变温培养

Ocular bacterial infections at a tertiary eye center in China: a 5-year review of pathogen distribution and antibiotic sensitivity

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International Journal of Ophthalmology(English edition) 2020年第1期13卷 54-60页

作者： wen gao Tian Xia Hua-Bo Chen Xiao-Jing Pan Yu-Sen Huang xin wa.g Yan-Ling Dong Li-xin Xie School of Medicine Shandong UniversityJinan 250012Shandong ProvinceChina State Key Laboratory Cultivation Base Shandong Provincial Key Laboratory of OphthalmologyShandong Eye InstituteShandong First Medical University&Shandong Academy of Medical SciencesQingdao 266071Shandong ProvinceChina Anhui No.2 Provincial People’s Hospital Hefei 230041Anhui ProvinceChina

AIM: To provide statistical evidence for the use of antibiotics in ophthalmology by assessing the distribution and antibiotic sensitivity of bacterial isolates from ocular specimens with suspected microbial ***: This study applied a retrospective analysis of 3690 bacterial isolates from ocular specimens, which were obtained from the conjunctiva, cornea, aqueous humor, vitreous body, and other ocular sites of the patients at Shandong Eye Institute in northern China from January 2013 to December 2017. The parameters assessed mainly included the distribution of isolated bacteria and the results of susceptibility tests for antibiotics. In the analysis of antibiotic sensitivities, the bacteria were divided into four groups according to gram staining, and statistical methods were used to compare their antibiotic sensitivities. RESULTS: Among the 3690 isolated bacterial strains, Staphylococcus epidermidis(2007, 54.39%) accounted for the highest proportion. As for the total isolates, their sensitivity rate to gatifloxacin was up to 90.01%, with four types of gram-stained bacteria being all highly sensitive to it, but their sensitivity rate to levofloxacin was only 51.91%. The sensitivity rate of gram-negative bacilli(g-B) to levofloxacin was 83.66%, significantly higher than the other three types of gram-stained bacteria(Pgram-positive cocci (g+C, 97.95%) and gram-positive bacilli(g+B, 97.54%) were more sensitive to vancomycin than gram-negative cocci(g-C, 70.59%) and g-B(68.57%;Pg+C(89.83%) and g+B(73.37%) were significantly higher than that of g-B(29.83%;Pgram-negative bacteria's sensitivity rate to cefuroxime was as low as 59.25%, but only g-B was less sensitive to cefuroxime(57.28%), while g-C was still highly sensitive(89.29%). The sensitivity rate of gram-positive bacteria to moxifloxacin was as high as 80.28%, but only g+C was highly sensitive to moxifloxacin(81.21%), while g+B was

关键词： bacteria ocular infections pathogen antibiotic sensitivity

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纤维对微表处混合料路用性能的影响分析

合成纤维 2024年第2期53卷 71-74页

作者：许雯西安思源学院陕西西安710038

为探究纤维掺量和种类对微表处混合料路用性能的影响效果,分别选用聚丙烯纤维、木质素纤维和玄武岩纤维制备微表处混合料,通过抗车辙变形、抗磨耗、抗水损以及低温抗裂性能测试,比较三种纤维制备的微表处混合料的各项性能。结果显示:微... 详细信息

为探究纤维掺量和种类对微表处混合料路用性能的影响效果,分别选用聚丙烯纤维、木质素纤维和玄武岩纤维制备微表处混合料,通过抗车辙变形、抗磨耗、抗水损以及低温抗裂性能测试,比较三种纤维制备的微表处混合料的各项性能。结果显示:微表处混合料的抗水损性能、抗磨耗性能和抗车辙变形能力均随纤维掺量的增加而表现出先降低后增加的变化,且抗磨耗性能和抗水损性能在纤维质量分数为0.1%时达到最佳,而抗车辙变形能力在纤维质量分数为0.2%时达到最大值;低温抗裂性能随纤维掺量的提升而提升。综合各项试验结果得出:掺加玄武岩纤维且质量分数为0.2%时,混合料的路用性能最佳,推荐预防性养护工程中使用该材料用于微表处混合料。

关键词：纤维微表处混合料沥青路面路用性能预防性养护

Advances in photothermal conversion of carbon dioxide to solar fuels

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能源化学:英文版 2023年第8期83卷 62-78,I0004页

作者： wa.gao Yinwen Li Dequan Xiao Ding Ma College of Bioscience and Resources Environment Beijing University of AgricultureBeijing 102206China College of Chemistry and Molecular Engineering and College of Engineering Peking UniversityBeijing 100871China Center for Integrative Materials Discovery Department of Chemistry and Chemical and Biomedical EngineeringUniversity of New HavenWest HavenCT 06516USA

Converting carbon dioxide(CO_(2)) into useful fuels or chemical feedstocks is important for achieving peak carbon emission and carbon ***,photothermal catalysis has been extensively studied and applied due to its advantages over traditional heat-driven *** this review,we focus on photothermal catalysis of thermodynamically uphill reactions that convert CO_(2)into value-added *** first introduce the fundamentals of photothermal catalysis for CO_(2)reduction,including the definition and classification of photothermal catalysis,followed by their photothermal conversion *** structure design of different types of photothermal catalysts is *** superior performance of photothermal catalytic conversion of CO_(2)is illustrated and discussed,including improved CO_(2)activation,tunable selectivity towards different solar fuel products,and resistance to sintering and ***,the perspectives and challenges in this cutting-edge field are presented with the aim of advancing understanding of the underlying mechanisms and inspiring rational design of photothermal catalysts for highly efficient solar-to-fuel conversion.

关键词： Solarenergy Photothermal catalysis CO_(2)reduction Catalyst design Performance improvement

Application of Shear wave Elastography and Contrast-Enhanced Ultrasound in Transrectal Prostate Biopsy

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Current Medical Science 2022年第2期42卷 447-452页

作者： gao-wa SHAREN Jun ZHANg Department of Ultrasound Affiliated Hospital of Inner Mongolia Medical UniversityHohhot010050China Department of Urology Affiliated Hospital of Inner Mongolia Medical UniversityHohhot010050China

Objective To explore the clinical value of ultrasound shear wave elastography(SWE)and contrast-enhanced ultrasound(CEUS)in transrectal prostate *** A total of 54 patients(average age:67.79±12.01 years)in the experimental group underwent transrectal prostate biopsy under the guidance of SWE,while 46 patients(average age:69.22±11.54 years)in the control group underwent transrectal prostate biopsy guided by *** There were a total of 451 needles,with an average of 8.35±1.67 needles per patient in the experimental group,and a total of 462 needles,with an average of 10.04±1.33 needles per patient in the control *** difference in puncture times between the two groups was statistically significant(Pwas no significant difference in the positive detection rate,sensitivity or specificity between the two groups(P>0.05),but there was a significant difference in the diagnostic accuracy between the two groups(Pgnificantly higher in the experimental group than in benign prostatic hyperplasia(Pg characteristic curve(ROC)analysis showed that the area under the ROC curve(AUC)of E_(mean)was 0.752(S.E.=0.072,95%CI=0.611-0.894,P=0.007),and the best cutoff value was 47.005 *** In summary,both SWE-and CEUS-guided transrectal prostate biopsy can help find the focus and guide the puncture,and improve the positive detection rate.

关键词： prostate puncture ultrasonic shear wave elastography contrast-enhanced ultrasound biopsy analysis

Nanostructured Catalyst for Fischer-Tropsch Synthesis

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Chinese Journal of Chemistry 2018年第9期36卷 798-808页

作者： wa.gao Qingshan Zhu Ding Ma College of Chemistry and Molecular Engineering and College of Engineering Peking University Beijing 100871 China Fritz-Haber-Institut der Max-Planck-gesellschaft Faradayweg 4-6 D-14195 Berlin Germany

Fischer-Tropsch synthesis （FTS） is a heterogeneous catalytic process for the production of fuels or chemicals from synthesis gas （CO ＋ H2）, which can be derived from nonpetroleum feedstocks such as natural gas, coal, or biomass. Co, Ru, Fe and Ni are all active in FTS, but only cheaper Fe and Co based catalysts are used in industry because the price of Ru is relatively high. However, the industrial Fe- and Co-based FTS catalysts normally work at a relatively high temperature range of 493--623 K in order to get a reasonable space time yield. Moreover, the product selectivity of FTS is governed by the law of polymerization, i.e., a so-called Anderson-Schulz-FIory distribution holds, which restricts its industrial application. In this account, we highlight some of our progress toward the design/fabrication of nanostructured Fe, Co and Ru catalysts to improve FTS activity at the low temperature and to change the product selectivity and confine the product distribution into a certain range.

关键词： catalyst Fischer-Tropsch synthesis nanostructure