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Modulated hydrocarbon distribution of gasoline deriving from butene conversion in the presence of syngas

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Journal of Energy Chemistry 2022年第10期31卷 416-421,I0010页

作者： yi Ding feng Jiao Xiulian pan Xinhe Bao Department of Chemical Physics University of Science and Technology of ChinaHefei 230026AnhuiChina State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy2011-Collaborative Innovation Center of Chemistry for Energy MaterialsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

With the expansion of butene production capacity,clean and efficient conversion of mixed butene attracts increasing attention.Herein we report direct co-conversion of butene and syngas to highquality gasoline enabled by a bifunctional OXZEO catalyst comprising ZnCrO_(x) oxide and ZSM-5 zeolite.A gasoline selectivity of 71.6% at 98.1% butene conversion and 26.2% CO conversion have been obtained under the reaction conditions of 360℃,3 MPa and 3000 mL g^(-1) h^(-1).The space time yield of gasoline of0.25 g·g^(-1) h^(-1) is achieved.Interestingly,the presence of syngas can effectively facilitate iso-paraffin production while hindering the formation of aromatics.This is attributed to the prohibited hydrogen transfer aromatization process of butene on ZSM-5 in the presence of H2.Fu rthermore,the formation of isomers of gasoline range hydrocarbons is favored because the active intermediates generated from CO/H_(2) activation over ZnCrO_(x) oxide could react with butene over ZSM-5 zeolite.Thus,the product distribution among gasoline range hydrocarbons is modulated with reduced heavy aromatics and improved iso-paraffins,which is desirable for application as fuels.This provides an alternative environmentally friendly technology to utilize still increasing mixed butene.

关键词： Butene utilization Bifunctional catalysts OXZEO Syngas conversion Gasoline

Effects of magnesium and copper additions on tensile properties of Al-Si-Cr die casting alloy under as-cast and T5 conditions

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China Foundry 2023年第1期20卷 12-22页

作者： Hong-yi Zhan yi-wu Xu pan Wang Jian-feng Wang Jin-ping Li Le-peng Zhang General Motors Global Research&Development China Science LaboratoryShanghai 201206China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China General Motors(China)Investment Co. Ltd.Shanghai 201206China China International Intellectech Corporation(CIIC) Beijing 100004China

Aluminum high pressure die casting(HPDC)technology has evolved in the past decades,enabling stronger and larger one-piece casting with significant part consolidation.It also offers a higher design freedom for more mass-efficient thin-walled body structures.For body structures that require excellent ductility and fracture toughness to be joined with steel sheet via self-piercing riveting(for instance,shock towers and hinge pillars,etc.),a costly T7 heat treatment comprising a solution heat treatment at elevated temperatures(450℃-500℃)followed by an over-ageing heat treatment is needed to optimize microstructure for meeting product requirement.To enable cost-efficient mass production of HPDC body structures,it is important to eliminate the expensive T7 heat treatment without sacrificing mechanical properties.Optimizing die cast alloy chemistry is a potential solution to improve fracture toughness and ductility of the HPDC components.The present study intends to tailor the Mg and Cu additions for a new Al-Si-Cr type die casting alloy(registered as A379 with The Aluminum Association,USA)to achieve the desired tensile properties without using T7 heat treatment.It was found that Cu addition should be avoided,as it is not effective in enhancing strength while degrades tensile ductility.Mg addition is very effective in improving strength and has minor impact on tensile ductility.The investigated Al-Si-Cr alloy with a nominal composition of Al-8.5wt.%Si-0.3wt.%Cr-0.2wt.%Fe shows comparable tensile properties with the T7 treated AlSi10MnMg alloy which is currently used for manufacturing shock towers and hinge pillars.

关键词： Al-Si alloy intermetallics high pressure die casting tensile property T7 heat treatment

Dynamic confinement of SAPO-17 cages on the selectivity control of syngas conversion

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National Science Review 2022年第9期9卷 40-46页

作者： Haodi Wang feng Jiao yi Ding Wenjuan Liu Zhaochao Xu Xiulian pan Xinhe Bao State Key Laboratory of Catalysis 2011-Collaborative Innovation Center of Chemistry for Energy Materials Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Chemical Physics University of Science and Technology of China Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical Physics Chinese Academy of Sciences

The OXZEO(oxide-zeolite) bifunctional catalyst concept has enabled selective syngas conversion to a series of value-added chemicals and fuels such as light olefins,aromatics and gasoline.Herein we report for the first time a dynamic confinement of SAPO-17 cages on the selectivity control of syngas conversion observed during an induction period.Structured illumination microscopy,intelligent gravimetric analysis,UV-Raman,X-ray diffraction,thermogravimetry and gas chromatography-mass spectrometer analysis indicate that this is attributed to the evolution of carbonaceous species as the reaction proceeds,which gradually reduces the effective space inside the cage.Consequently,the difusion of molecules is hindered and the hindering is much more prominent for larger molecules such as C4+.As a result,the selectivity of ethylene is enhanced whereas that of C4+is suppressed.Beyond the induction period,the product selectivity levels off.For instance, ethylene selectivity levels off at 44% and propylene selectivity at 31 %,as well as CO conversion at 27%.The findings here bring a new fundamental understanding that will guide further development of selective catalysts for olefin synthesis based on the OXZEO concept.

关键词： syngas conversion OXZEO dynamic confinement zeolite diffusion

Intelligent Electrocardiogram Analysis in Medicine:Data,Methods,and Applications

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Chinese Medical Sciences Journal 2023年第1期38卷 38-48页

作者： Yu-Xia Guan ying An feng-yi Guo Wei-Bai pan Jian-Xin Wang Hunan Provincial Key Lab on Bioinformatics School of Computer Science and EngineeringCentral South UniversityChangsha 410083China Big Data Institute Central South UniversityChangsha 410083China

Electrocardiogram(ECG)is a low-cost,simple,fast,and non-invasive test.It can reflect the heart’s electrical activity and provide valuable diagnostic clues about the health of the entire body.Therefore,ECG has been widely used in various biomedical applications such as arrhythmia detection,disease-specific detection,mortality prediction,and biometric recognition.In recent years,ECG-related studies have been carried out using a variety of publicly available datasets,with many differences in the datasets used,data preprocessing methods,targeted challenges,and modeling and analysis techniques.Here we systematically summarize and analyze the ECGbased automatic analysis methods and applications.Specifically,we first reviewed 22 commonly used ECG public datasets and provided an overview of data preprocessing processes.Then we described some of the most widely used applications of ECG signals and analyzed the advanced methods involved in these applications.Finally,we elucidated some of the challenges in ECG analysis and provided suggestions for further research.

关键词： Electrocardiogram database preprocessing machine learning medical big data analysis

Mass screening is a key component to fight against SARS-CoV-2 and return to normalcy

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Medical Review 2022年第2期2卷 197-212页

作者： Zhaomin feng yi Zhang Yang pan Daitao Zhang Lei Zhang Quanyi Wang Beijing Center for Disease Prevention and Control BeijingChina Queensland University of Technology BrisbaneAustralia

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had highly transmissible and pathogenic, which caused serious economic loss and hazard topublic health. Different countries have developed strategiesto deal with the COVID-19 pandemic that fit their epidemiological situations, capacities, and values. Mass screeningcombined with control measures rapidly reduced thetransmission of the SARS-CoV-2 infection. The COVID-19pandemic has dramatically highlighted the essential role ofdiagnostics capacity in the control of communicable diseases. Mass screening has been increasingly used to detectsuspected COVID-19 cases and their close contacts, asymptomatic case, patients attending fever clinics, high-riskpopulations, employees, even all population to identifyinfectious individuals. Mass screening is a key component tofight against SARS-CoV-2 and return to normalcy. Here wedescribe the history of mass screening, define the scope ofmass screening, describe its application scenarios, anddiscuss the impact and challenges of using this approach tocontrol COVID-19. We conclude that through a comprehension screening program and strong testing capabilities, massscreening could help us return to normalcy more quickly.

关键词： close contacts diagnostics capacity mass screening SARS-CoV-2

Secrecy outage performance for wireless-powered relaying systems with nonlinear energy harvesters

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Frontiers of Information Technology & Electronic Engineering 2017年第2期18卷 246-252页

作者： Ji-liang ZHANG Gao-feng pan yi-yuan XIE Electronic and Information Engineering Southwest University Chongqing 300715 China

本文考虑了一个包含单一信源、单一信宿、N(N>1)个无线充电中继和单一窃听者的协作系统。本文假设每个中继都拥有一个非线性的能量收集器,且该能量收集器存在一个饱和阈值以限制收集能量的大小。在考虑解码转发和功率分配接收器的场景中... 详细信息

本文考虑了一个包含单一信源、单一信宿、N(N>1)个无线充电中继和单一窃听者的协作系统。本文假设每个中继都拥有一个非线性的能量收集器,且该能量收集器存在一个饱和阈值以限制收集能量的大小。在考虑解码转发和功率分配接收器的场景中,本文选择第K个最优中继来协助信源-中继-信宿链路的传输。同时,本文还推导了保密中断概率的解析表达式,并用通过仿真验证了分析结果。

关键词：解码转发能量收集非线性保密中断概率

Analysis of the relationship between blood pressure variability and subtle cognitive decline in older adults

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World Journal of Psychiatry 2023年第11期13卷 872-883页

作者： Hui-feng Guo yi Wu Jie Li feng-feng pan Department of Gerontology Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200233China Prenatal Diagnosis Center International Peace Maternity&Child Health HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200030China

BACKGROUND Blood pressure variability(BPV)has been shown to be related to mild cognitive impairment and Alzheimer's disease in a number of studies.However,the relationship between BPV and subtle cognitive decline(SCD)has received minimal attention in this field of research to date and has rarely been reported.AIM To examine whether SCD is independently associated with changes in BPV in older adults.METHODS Participants were selected based on having participated in cognitive function evaluation and ambulatory blood pressure measurement at the Shanghai Sixth People's Hospital Affiliated with Shanghai Jiao Tong University School of Medicine between June 2020 and August 2022.The participants included 182 individuals with SCD as the experimental group and 237 with normal cognitive function as the control group.The basic data,laboratory examinations,scale tests,and ambulatory blood pressure test results of the two groups were analyzed retrospectively,and the relationship between SCD and BPV was subsequently evaluated.RESULTS Significant differences were observed between the two groups of participants(P<0.05)in terms of age,education level,prevalence rate of diabetes,fasting blood glucose level,24-h systolic blood pressure standard deviation and coefficient of variation,24-h diastolic blood pressure standard deviation and coefficient of variation.The scale monitoring results showed significant differences in the scores for memory,attention,and visual space between the experimental and control groups.Logistic regression analysis indicated that age,education level,blood sugar level,and BPV were factors influencing cognitive decline.Linear regression analysis showed that there was an independent correlation between blood pressure variation and SCD,even after adjusting for related factors.Each of the above differences was still significant.CONCLUSION This study suggests that increased BPV is associated with SCD.

关键词： Blood pressure Variability Elderly Subtle cognitive decline relationship

Dendrobium nobile protects against ovalbumin-induced allergic rhinitis by regulating intestinal flora and suppressing lung inflammation

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Chinese Journal of Natural Medicines 2022年第6期20卷 443-457页

作者： DUAN Fei-Peng LI yi-Sheng HU Tian-Yong pan Xin-Quan MA Fang feng Yue QIU Shu-Qi ZHENG yi-Qing Institute of Otolaryngology Institute of Hearing and Speech of Sun Yat-sen UniversitySun Yat-sen Me-morial HospitalSun Yat-sen UniversityGuangzhou 510520China Department of Otolaryngology Longgang E.N.T hospital&Shenzhen Key Laboratory of E.N.TInstitute of E.N.TShenzhen 518172China

Antibiotic exposure-induced dysbiosis of the intestinal flora increases the risk of developing allergic rhinitis.Hence,regulating the balance of intestinal flora may be useful for preventing and treating allergic rhinitis.However,the underlying mechanism is unclear.Dendrobium nobile(Shihu)exhibits anti-inflammatory and immune activities.Hence,in this study,we investigated the mechanism via which Shihu may improve allergic rhinitis.Mouse models of allergic rhinitis with intestinal flora dysbiosis(Model-D,antibiotics induce intestinal flora dysbiosis with ovalbumin-induced allergy)and normal intestinal flora with allergic rhinitis(Model-N,ovalbumin-induced allergy)were established.The effect of Shihu on intestinal flora and inflammation caused during allergic rhinitis were analyzed.Allergic symptoms,infiltration of hematoxylin and eosin in the lungs and nose,and the release of various factors[interleukin(IL)-2,IL-4,IFN-y,IL-6,IL-10,and IL-17]in the lungs were evaluated.The results indicate that intestinal flora dysbiosis exacerbated lung and nose inflammation in allergic rhinitis.However,treatment with the Shihu extract effectively reversed these symp-toms.Besides,the Shihu extract inhibited the PI3K/AXT/mTOR pathway and increased the level of Forkhead box protein in the lungs.Additionally,the Shihu extract reversed intestinal flora dysbiosis at the phylum and genus levels and improved regulator T cell differentiation.Furthermore,in the Model-D group,the Shihu extract inhibited the decrease in the diversity and abundance of the intestinal flora.Screening was performed to determine which intestinal flora was positively correlated with Treg differentiation using Spearman5 s correlation analysis.In conclusion,we showed that Shihu extract restored the balance in intestinal flora and ameliorated inflammation in the lungs of allergic rhinitis mice and predicted a therapeutic new approach using Traditional Chinese Medicine to improve allergic rhinitis.

关键词： Dendrobium nobile(Shihu) Allergic rhinitis Intestinal flora Regulator T cell Inflammation

In-situ synthesis of gadolinium niobate quasi-binary composites with balanced mechanical and thermal properties for thermal barrier coatings

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Journal of Advanced Ceramics 2022年第9期11卷 1445-1456页

作者： yi HAN Peng-an ZONG Muzhang HUANG Zesheng YANG yingjie feng Wei pan Peng ZHANG Chunlei WAN State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Institute of Welding and Surface Engineering Technology Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

Yttria-stabilized zirconia(YSZ)has been used as a thermal barrier coating(TBC)material in gas turbines for several decades.Although continuous efforts have been made to develop novel TBC materials that can work at a higher temperature,no single material other than YSZ has all the desired attributes for the TBCs.In this paper,we report the in-situ synthesis of quasi-binary GdNbO_(4)/Gd_(3)NbO_(7)composites based on the simple Gd_(2)O_(3)-Nb_(2)O_(5)binary phase diagram.The fracture toughness of these quasi-binary composites is remarkably enhanced compared with the value predicted by the rule of mixtures because the ferroelastic domain switching is more activated due to the residual stress in the quasi-binary composites,which triggers more crack defections due to the enlarged process zone.Additionally,the Gd_(3)NbO_(7)phase provides a low thermal conductivity due to the substantial chemical inhomogeneity,which diffuses phonons.Gd_(3)NbO_(7)/GdNbO_(4)exhibits a balanced thermal conductivity of 1.6 W/(m·K)at 1073 K and a toughness value of 2.76 MPa·m0.5,and these values are among the best comprehensive properties that have been obtained for new TBC materials.The work demonstrates a feasible approach of designing a new TBC material with balanced properties and can be easily fabricated.

关键词： thermal barrier coating(TBC) fracture toughness thermal conductivity residual stress