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Petroleum Science 2023年第3期20卷 1895-1902页

作者： Di Hu En-hua Wang Ao-Cheng Wang Ai-jun duan State Key Laboratory of Heavy Oil Processing China University of Petroleum-BeijingBeijing102249China

NizP supported catalysts exhibit high catalytic activities in hydrogenation reaction,of which the particle sizes of Ni_(2)P active phases are the key influential factor.This research focus on the effect of chelators on the size of Ni_(2)P particles over wrinkle silica nanoparticles(WSNs)by introducing chelating agents EDTA and NTA during impregnation process.The characterization results show that chelators modified cata-lysts possess smaller size of Ni_(2)P particles than the unmodified Ni_(2)P catalysts.Among all the synthesized catalysts,the EDTA modified Ni_(2)PE(1.5)/WSNs catalyst possesses smallest average particle size of Ni_(2)P,only 2.6 nm.Moreover,the Ni_(2)P catalysts with the assistance of EDTA exhibits better catalytic activity than that of NTA under high reaction temperature,which can be ascribed to the strong bonding between EDTA and Ni.And the EDTA modified Ni_(2)PE(1.5)/WSNs catalyst shows highest hydrogenation ability,almost reaching 100%decalin selectivity.

关键词： Wrinkle silica nanoparticles Chelators Ni_(2)P supported catalysts Naphthalene hydrogenation

Carrier Rate Analysis of Single-Gene Disorders Based on 1000 Genome Project and Exome Aggregation Consortium Data

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Reproductive and Developmental Medicine 2019年第4期3卷 235-242,I0001,I0002页

作者： Meng-Meng duan hua-jun Zheng Laboratory of Medical Foods NHC Key Laboratory of Reproduction Regulation(Shanghai Institute of Planned Parenthood Research)School of Basic Medical SciencesFudan UniversityShanghai 200032China

Objective:Screening variants underlying the single-gene disorder in the general population can help reduce the incidences of birth defects.To determine the most prevalent pathogenic variants causing autosomal recessive diseases,we investigated the frequencies of these variants in six major geographic ancestry groups from Exome Aggregation Consortium(ExAC)database and 26 populations from the 1,000 Genome Project,including three Chinese ethnic groups.Methods:We selected 64 autosomal recessive diseases and collected corresponding causal genes and variants from ClinVar for the analysis.The RS(reference single-nucleotide polymorphism)IDs of these variants were used to search the corresponding VCF file from the 1,000 Genomes Project and ExAC databases.We calculated the frequencies of heterozygotes of each disease variants in the 1,000 Genomes Project and ExAC samples and compared the distribution of disease alleles among different populations.Results:Our analysis revealed that 1,151/212 variants were carried by 60,706/2,504 individuals sequenced in the ExAC/1,000 Genomes Project.The average number of autosomal recessive disease alleles carried by samples from ExAC and 1,000 Genomes Project were 0.53 and 0.68,respectively.These disease alleles showed differential distribution among populations,and some disease alleles were significantly enriched in certain ethnic groups.In addition,1-2 main pathogenic variants were identified in each disease.Meanwhile,several ClinVar variants with relatively high frequency(>1%)in the samples were found to be benign instead of“conflicting evaluations of pathogenicity.”Conclusions:Our observations revealed that main pathogenic variants existed in certain autosomal recessive disease,suggesting that screening of disease hypermutations in different populations is valuable in reducing the occurrence of birth defects.

关键词： Single-Gene Disorders Exome Aggregation Consortium 1,000 Genomes Project Carrier Rate

Differences in parameter estimates derived from various methods for the ORYZA(v3) Model

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Journal of Integrative Agriculture 2022年第2期21卷 375-388页

作者： TAN jun-wei duan Qing-yun GONG Wei DI Zhen-hua College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083P.R.China College of Water Resources and Hydrology Hohai UniversityNanjing 210098P.R.China Institute of Land Surface System and Sustainable Development Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875P.R.China

Parameter estimation is always a difficult issue for crop model users, and inaccurate parameter values will result in deceptive model predictions. Parameter values may vary with different inversion methods due to equifinality and differences in the estimating processes. Therefore, it is of great importance to evaluate the factors which may influence parameter estimates and to make a comparison of the current widely-used methods. In this study, three popular frequentist methods(SCE-UA, GA and PEST) and two Bayesian-based methods(GLUE and MCMC-AM) were applied to estimate nine cultivar parameters using the ORYZA(v3) Model. The results showed that there were substantial differences between the parameter estimates derived by the different methods, and they had strong effects on model predictions. The parameter estimates given by the frequentist methods were obviously sensitive to initial values, and the extent of the sensitivity varied with algorithms and objective functions. Among the frequentist methods, the SCE-UA was recommended due to the balance between stable convergence and high efficiency. All the parameter estimates remarkably improved the goodness of model-fit, and the parameter estimates derived from the Bayesian-based methods had relatively worse performance compared to the frequentist methods. In particular, the parameter estimates with the highest probability density of posterior distributions derived from the MCMC-AM method(MCMC_P_(max)) led to results equivalent to those derived from the frequentist methods, and even better in some situations. Additionally, model accuracy was greatly influenced by the values of phenology parameters in validation.

关键词： parameter estimation frequentist method Bayesian method crop model calibration

Optimization of submerged entry nozzle parameters for ultra-high casting speed continuous casting mold of billet

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Journal of Iron and Steel Research(International) 2022年第1期29卷 44-52页

作者： Pei Xu Yong-zhi Zhou Deng-fu Chen Mu-jun Long hua-mei duan Laboratory of Metallurgy and Materials College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Controlling the flow behavior in the mold in an appropriate way is the basis for realizing the billet ultra-high speed continuous casting.Based on the new proposed physical water modeling experiment considering the effects of solidified shell and hydrostatic pressure,the flow behavior in the mold with cross section of 160 mm 9160 mm during continuous casting of billet is regulated by optimizing the inner diameters and immersion depths of submerged entry nozzle at the ultra-high casting speeds of 5.0–6.5 m/min.The results show that under the premise of no slag entrainment,as well as uniform coverage and keeping good fluidity of liquid slag layer on the top free surface of the fluid in the mold,the appropriate parameters of submerged entry nozzle under the ultra-high casting speed of billet are 50 mm in inner diameter,95 mm in outer diameter and 180 mm in immersion depth.And on the basis of the obtained parameters of submerged entry nozzle,it can be known that the reasonable ranges of level fluctuation and impacting depth of the stream in the mold are about 0.82-1.11 and 593-617 mm,respectively.

关键词： Ultra-high casting speed Billet continuous casting Submerged entry nozzle Physical water modeling Flow behavior

Electroreduction of carbon dioxide to multi-electron reduction products using poly(ionic liquid)-based Cu-Pd catalyst

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Fundamental Research 2022年第6期2卷 937-945页

作者： Xiao-Qiang Li Guo-Yi duan Xian-Xia Yang Li-jun Han Bao-hua Xu Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China National Fundamental Research Laboratory of New Hazardous Chemicals Assessment and Accident Analysis Institute of Applied ElectrochemistryBeijing University of Chemical TechnologyBeijing 100029China

Electrocatalytic reduction of CO_(2)(CO_(2)RR)to multi-electron(>2e–)products provides a green and sustainable route for producing fuels and chemicals.Introducing the second metal element is a feasible strategy for"managing"the key intermediate on Cu-based materials to further improve the CO_(2)RR catalytic performance.In this work,palladium,which promises the generation of CO,was introduced into the poly(ionic liquid)-based copper hybrid(Cu@PIL)to construct a novel Cu-Pd bimetallic electrocatalyst(Cu@PIL@Pd).Remarkably,with a small dosage of palladium(2.0 mol%compared with Cu),a high faradaic efficiency(FE)for C_(2+)products(68.7%)was achieved at–1.01 V(with respect to the reversible hydrogen electrode(RHE),the same below)with a high partial current density of 178.3 mA cm^(-2).Meanwhile,high selectivity towards CH4(FE=42.5%)and corresponding partial current density of 172.8 mA cm^(-2)were obtained on the same catalyst at–1.24 V,signifying a significant potential-dependent selectivity.Mechanistic studies reveal that both copper and palladium oxides are reduced to metallic states during the CO_(2)RR.The presence of the adjoint copper phase and the highly dispersed electrostatic layer promote the generation of CO on the palladium components(both the PdO_(2)phase and the Pd(II)site).Besides,the local CO^(*)was enriched by the significant diffusion resistance of CO in the PIL layer.The spillover of CO^(*)from Pd sites to the adjoint Cu sites,accompanied by the increased local concentration of CO^(*)around Cu sites,accounted for the observed good CO_(2)RR catalytic performance,especially the high C_(2+)product selectivity.

关键词： CO_(2)conversion Bimetallic catalyst Cu-Pd material Electrolysis High-value products

Downregulation of signal transduction and STAT3 expression exacerbates oxidative stress mediated by NLRP3 inflammasome

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Neural Regeneration Research 2018年第12期13卷 2147-2155页

作者： hua Bai Qi-Fang Zhang Juan-Juan duan De-jun Yu Li-Jie Liu Medical Laboratory Center Third Affiliated Hospital Guizhou Medical University Department of Neurology Third Affiliated Hospital Guizhou Medical University Key Laboratory of Endemic and Ethnic Diseases of Ministry of Education and Key Laboratory of Medical Molecular Biology Guizhou Medical University

Activated nucleotide binding to the oligonucleotide receptor protein 3（NLRP3） inflammasome is possibly involved in the pathogenesis of Alzheimer＇s disease through oxidative stress and neurogenic inflammation. Low expression of the signal transducer and activator of transcription 3（STAT3） gene may promote the occurrence of neurodegenerative diseases to some extent. To clarify the roles of the NLRP3 inflammasome and STAT3 expression in oxidative stress,（1） SHSY5 Y cells were incubated with 1 mM H2 O2 to induce oxidative stress injury, and the expression of human-cell-specific signal transduction, STAT3-shRNA silencing signal transduction and STAT3 were detected. Cells were pretreated with Ca2＋ chelator BAPATA-AM（0.1 mM） for 30 minutes as a control.（2） Western blot assay was used to analyze the expression of caspase-1, NLRP3, signal transduction and STAT3. Enzyme-linked immunosorbent assay was used to analyze interleukin-1β levels. Flow cytometry was carried out to calculate the number of apoptotic cells. We found that H2 O2 treatment activated NLRP3 inflammasomes and decreased phosphorylation of signal transduction and STAT3 serine 727. BAPTA-AM pretreatment abolished the H2 O2-induced activation of NLRP3 inflammasomes, caspase-1 expression, interleukin-1β expression and apoptosis in SHSY5 Y cells, and had no effect in cells with downregulated STAT3 expression by RNAi. The findings suggest that downregulation of signal transduction and STAT3 expression may enhance the oxidative stress mediated by NLRP3, which may not depend on the Ca2^＋ signaling pathway.

关键词： nerve regeneration signal transducer and activator of transcription 3 calcium caspase-l nucleotide binding to the oligonucleotide receptor protein 3 inflammasome hydrogen peroxide Alzheimer＇s disease shRNA SHSYSY cells neural regeneration

Moderate drought alleviates the damage to grain quality at high temperatures by improving the starch synthesis of inferior grains in japonica rice

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Journal of Integrative Agriculture 2022年第10期21卷 3094-3101页

作者： TONG Hui duan hua WANG Sheng-jun SU Jing-ping SUN Yue LIU Yan-qing TANG Liang LIU Xue-jun CHEN Wen-fu Rice Research Institute Shenyang Agricultural UniversityShenyang 110866P.R.China Tianjin Key Laboratory of Crop Genetics and Breeding Tianjin Crop Research InstituteTianjin 300384P.R.China

In agricultural production,temperature and moisture are important factors affecting grain yield and quality.Although moderate drought at the grain-filling stage can effectively alleviate the damage caused by high temperature,the specific regulatory mechanism driving the effect of moderate drought at the high temperature on starch synthesis is still unclear.To explore the effects and mechanisms of high temperature and moderate drought on rice starch synthesis at the grainfilling stage,the activities of enzymes and expression levels of the genes involved in starch synthesis under four different treatments involving high temperature and/or water stress(CK,HT,WS,and HT+WS)were investigated in this study.The starch synthesis of a japonica inbred rice was measured under the four treatments during the grain filling.The results show that the effects of high temperature and moderate drought on grain filling mainly occur in the inferior grains of rice.Through the regulation of enzymes involved in starch synthesis and the expression levels of their main genes,the synthesis of rice starch can be affected.Therefore,the high temperature and moderate drought were antagonistic,and moderate drought can alleviate the damage to grain quality at a high temperature by improving the starch synthesis of inferior grains in japonica rice.This study provides a basis for stress-resistance cultivation and breeding strategies of rice with high temperature tolerance.

关键词： high temperature moderate drought antagonism starch synthesis japonica rice

Size effect of lattice material and minimum weight design

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Acta Mechanica Sinica 2014年第2期30卷 191-197页

作者： jun Yan Wen-Bo Hu Zhen-hua Wang Zun-Yi duan Dalian University of Technology

The size effects of microstructure of lattice materials on structural analysis and minimum weight design are studied with extented multiscale finite element method（EMsFEM） in the paper. With the same volume of base material and configuration, the structural displacement and maximum axial stress of micro-rod of lattice structures with different sizes of microstructure are analyzed and compared.It is pointed out that different from the traditional mathematical homogenization method, EMsFEM is suitable for analyzing the structures which is constituted with lattice materials and composed of quantities of finite-sized micro-rods.The minimum weight design of structures composed of lattice material is studied with downscaling calculation of EMsFEM under stress constraints of micro-rods. The optimal design results show that the weight of the structure increases with the decrease of the size of basic sub-unit cells. The paper presents a new approach for analysis and optimization of lattice materials in complex engineering constructions.

关键词： Lattice material Light weight design Size ef-fect Extented multiscale finite element method

High-precision low-power quartz tuning fork temperature sensor with optimized resonance excitation

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第4期14卷 264-273页

作者： jun XU Xin LI Jin-hua duan Hai-bo XU College of Automation Harbin University of Science and Technology Computer Center Harbin University of Science and Technology

This paper presents the design,fabrication,and characterization of a quartz tuning fork temperature sensor based on a new ZY-cut quartz crystal bulk acoustic wave resonator vibrating in a flexural mode.Design and performance analysis of the quartz tuning fork temperature sensor were conducted and the thermal sensing characteristics were examined by measuring the resonance frequency shift of this sensor caused by an external temperature.Finite element method is used to analyze the vibratory modes and optimize the structure of the sensor.The sensor prototype was successfully fabricated and calibrated in operation from 0 to 100 ℃ with the thermo-sensitivity of 70×10-6/℃.Experimental results show that the sensor has high thermo-sensitivity,good stability,and good reproducibility.This work presents a high-precision low-power temperature sensor using the comprehensive thermal characterization of the ZY-cut quartz tuning fork resonator.

关键词：温度传感器石英音叉高精度低功耗优化激励共振振动模式

Effect of Tai Chi on Cardiac and Static Pulmonary Function in Older Community-Dwelling Adults at Risk of Ischemic Stroke: A Randomized Controlled Trial

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Chinese Journal of Integrative Medicine 2019年第8期25卷 582-589页

作者： ZHENG Guo-hua ZHENG Xin LI jun-zhe duan Ting-jin TAO Jing CHEN Li-dian College of Nursing and Health Management Shanghai University of Medicine and Health Sciences Shanghai (201318) China College of Rehabilitation Medicine Fujian University of Traditional Chinese Medicine Fuzhou (350122)China Department of Physical Education Fujian University of Traditional Chinese Medicine Fuzhou (350122)China Fujian Key Laboratory of Rehabilitati on Tech no logy Fujia n Un iversity of Traditional Chinese Medicine Fuzhou (350122)China Collaborative Inno vation Cen ter for Rehabilitati on Tech no logy Fujian University of Traditional Chinese Medicine Fuzhou (350122)China

Objective: To evaluate the effect of tai chi exercise on cardiac and static lung function for older community-dwelling adults at risk of ischemic stroke. Methods: A total of 170 older community-dwelling adults (aged 55–75 years old) at risk of ischemic stroke were allocated to either tai chi training group (85 cases, five 60-min sessions of tai chi training per week for 12 weeks) or control group (85 cases, usual pbysical activity for 12 weeks) using a computer-generated randomization. The echocardiographic parameters of cardiac structure, cardiac function and static lung function were measured at baseline, after 12 weeks of intervention and additional 12-week follow-up period by a blinded professional staff member using a color Doppler ultrasound imaging device or a cardiopulmonary function instrument. The t test and linear mixed model based on the intention-to-treat analysis principle was used to calculate the effect. The adverse effect was observed. Results: Most of echocardiographic parameters on the cardiac structure, cardiac function and static lung function between the tai chi group and control group did not have a significant difference either post 12-week intervention or additional 12-week follow-up period. Only three parameters involving in right ventricular diameter (P=0.024), main pulmonary artery diameter (P=0.002) and vital capacity maximum (P=0.036) were beneficial to be improved in the tai chi group compared to the control group by the analysis of mixed linear model. No adverse effects were found during the intervention period. Conclusions: The 12-week tai chi exercise did not have an obvious beneficial effect on cardiac structure, cardiac function and static lung function in older community-dwelling adults at risk of ischemic stroke.(Trial registration No. ChiCTR-TRC-13003601)

关键词： tai chi cardiac structure and function static lung function ischemic stroke randomized controlled trial