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    题名 作者 年代 出处 被引量
1A Review on Representative Swarm Intelligence Algorithms for Solving Optimization Problems:Applications and Trends显示文摘Swarm intelligence algorithms are a subset of the artificial intelligence(AI)field,which is increasing popularity in resolving different optimization problems and has been widely utilized in various applications.In the past decades,numerous swarm intelligence algorithms have been developed,including ant colony optimization(ACO),particle swarm optimization(PSO),artificial fish swarm(AFS),bacterial foraging optimization(BFO),and artificial bee colony(ABC).This review tries to review the most representative swarm intelligence algorithms in chronological order by highlighting the functions and strengths from 127 research literatures.It provides an overview of the various swarm intelligence algorithms and their advanced developments,and briefly provides the description of their successful applications in optimization problems of engineering fields.Finally,opinions and perspectives on the trends and prospects in this relatively new research domain are represented to support future developments.Jun Tang Gang Liu Qingtao Pan 2021IEEE/CAA Journal of Automatica Sinica2021,8,10:18
2Influence of the post-treatment of HZSM-5 zeolite on catalytic performance for alkylation of benzene with methanol显示文摘The porous material HZSM-5 zeolite with micro-mesopore hierarchical porosity was prepared by post-treatment(combined alkali treatment and acid leaching) of parent zeolite and its catalytic performance for benzene alkylation with methanol was investigated. The effect of post-treatment on the textural properties was characterized by various techniques(including ICP-AES, XRD, nitrogen sorption isotherms, SEM, NH3-TPD, Py-IR and TG). The results indicated that the post-treatment could modify the structural and acidic properties of HZSM-5 zeolite. In this procedure, not only additional mesopores were created by selective extraction of silicon but also the acidity was tuned. Consequently, the modified HZSM-5 zeolite showed larger external surface area with less acid sites as compared to the parent zeolite. It was found out that the modified zeolite exhibited a higher benzene conversion and xylene selectivity for alkylation of benzene with methanol as well as excellent life span of the catalyst than conventional ones. This can be explained by the facts that the presence of additional mesopores improved the diffusion property in the reactions. Furthermore, the modified zeolite showed an appropriate Br?nsted acidity for effective suppression of the side reaction of methanol to olefins, thus reduced the accumulation of coke on the HZSM-5 zeolite, which was favorable for the catalyst stability. In comparison with the parent HZSM-5 zeolite,the modified zeolite by alkali treatment and acid leaching showed better performance for the benzene alkylation with methanol.Qingtao Wang Wenwen Han Hualei Hu Jinghui Lyu Xiaolong Xu Qunfeng Zhang Hongjing Wang Xiaonian Li 2017Chinese Journal of Chemical Engineering2017,25,12:13
3Spatial distribution, seasonal variation and regionalization of PM_(2.5) concentrations in China显示文摘In order to provide scientific support to policy makers in the regulation of PM2.5 pollution in China, it is important to accurately assess the current status, spatiotemporal characteristics and regionalization data for this air pollutant. An analysis of the pollution status of PM2.5 was conducted using daily averaged mass concentration data recorded in 74 cities in 2013 and 161 cities in 2014. The rotated empirical orthogonal function(REOF) method was applied to analyze this data. Results showed that the average annual PM2.5 concentration in urban areas of China is 62.2±21.5 ?g/m3, and that the distribution is spatially heterogeneous. The North China Plain, middle and lower Yangtze River Plain, Sichuan Basin and Guanzhong Plain had relatively high annual PM2.5 concentrations compared with the southeast coastal region, the Tibetan Plateau and the Yungui Plateau. PM2.5 mass concentrations tended to be higher in winter than in summer, however, the data for many cities showed a small peak in concentrations from May to July. An analysis of the spatial correlation of PM2.5 indicated a significant influence of topographic conditions. A lower correlation was observed where terrain features varied greatly. Based on the results of the REOF analysis and topographic characteristics, ten regions were identified in mid-eastern China, which could be considered as basic pollution prevention divisions for PM2.5; these include the North China Plain region, Pearl River Delta region, Jianghuai Plain region, middle Yangtze River Plain region, Northeast Plain region, Jiangnan coastal region, Sichuan Basin region, Qiantao Plain region, Guanzhong-Central Plain region and Yungui Plateau region. Seasonal variations in the regionalization data were observed, especially for the North China Plain and Pearl River Delta regions. Among the ten regions identified in this study, the North China Plain, Guanzhong-Central Plain, middle Yangtze River Plain and Jianghuai Plain had relatively high PM2.5 mass concentrations in comparison with the others. Therefore, these regions should be considered as the key regions to target in developing PM2.5 pollution prevention strategies. This study improves the present understanding of the spatial distribution, seasonal changes and regional status of PM2.5 pollution in China and helps establish possible control strategies for the reduction of this air pollutant.Shuai Wang Guogang Li Zhengyu Gong Li Du Qingtao Zhou Xiaoyan Meng Shuyan Xie Lei Zhou 2015Science China Chemistry2015,58,9:12
4Benzene alkylation with methanol over phosphate modified hierarchical porous ZSM-5 with tailored acidity显示文摘The acidity and acid distribution of hierarchical porous ZSM-5 were tailored via phosphate modification. The catalytic results showed that both benzene conversion and selectivity of toluene and xylene increased with the presence of appropriate amount of phosphorus. Meanwhile, side reactions such as methanol to olefins related with the formation of by-product ethylbenzene formation and isomerization of xylene to meta-xylene were suppressed efficiently. The acid strength and sites amount of Br?nsted acid of the catalyst were crucial for improving benzene conversion and yield of xylene, whereas passivation of external surface acid sites played an important role in breaking thermodynamic equilibrium distribution of xylene isomers.Jinghui Lyu Hualei Hu Carolyn Tait Jiayao Rui Caiyi Lou Qingtao Wang Wenwen Han Qunfeng Zhang Zhiyan Pan Xiaonian Li 2017Chinese Journal of Chemical Engineering2017,25,9:11
5Research on the Mechanism of Penetration Increase by Flux in A-TIG Welding显示文摘The mechanism of penetration depth increased by activating flux in activating tungsten inert gas (A-TIG) weldingwas studied by measuring the distribution of trace element Bi in the weld and monitoring the change of arc voltageduring A-TIG welding of stainless steel 0Crl8Ni9 with fluxes SiO2 and TiO2. The results show that the mechanismof penetration depth in A-TIG welding depends on the sort of flux used. The weld pool convection after coating theflux SiO2 and flux TiO2 is changed inversely compared with convectional TIG welding without flux. The arc voltageis increased by flux SiO2 whilst flux TiO2 does not have effect on the arc voltage. The reason of penetration depthincrease for SiO2 is due to the constriction of arc plasma and the change of surface tension gradient. The increaseof weld penetration depth with TiO2 only ascribes to the change of surface tension gradient.Chunli YANG Sanbao LIN Fengyao LIU Lin WU Qingtao ZHANG 2003Journal of Materials Science & Technology2003,19,z1:8
6Actual evapotranspiration of subalpine meadows in the Qilian Mountains, Northwest China显示文摘As a main component in water balance,evapotranspiration(ET)is of great importance for water saving,especially in arid and semi-arid areas.In this study,the FAO(Food and Agriculture Organization)Penman-Monteith model was used to estimate the magnitude and temporal dynamics of reference evapotranspiration(ET0)in 2014 in subalpine meadows of the Qilian Mountains,Northwest China.Meanwhile,actual ET(ETc)was also investigated by the eddy covariance(EC)system.Results indicated that ETc estimated by the EC System was 583 mm,lower than ET0(923 mm)estimated by the FAO Penman-Monteith model in 2014.Moreover,ET0 began to increase in March and reached the peak value in August and then declined in September,however,ETc began to increase from April and reached the peak value in July,and then declined in August.Total ETc and ET0 values during the growing season(from May to September)were 441 and 666 mm,respectively,which accounted for 75.73%of annual cumulative ETc and 72.34%of annual cumulative ET0,respectively.A crop coefficient(kc)was also estimated for calculating the ETc,and average value of kc during the growing season was 0.81(ranging from 0.45 to 1.16).Air temperature(Ta),wind speed(u),net radiation(Rn)and soil temperature(Ts)at the depth of 5 cm and aboveground biomass were critical factors for affecting kc,furthermore,a daily empirical kc equation including these main driving factors was developed.Our result demonstrated that the ETc value estimated by the data of kc and ET0 was validated and consistent with the growing season data in 2015 and 2016.GAO Yunfei ZHAO Chuanyan Muhammad W ASHIQ WANG Qingtao RONG Zhanlei LIU Junjie MAO Yahua GUO Zhaoxia WANG Wenbin 2019Journal of Arid Land2019,11,3:8
7The Arabidopsis Spontaneous Cell Death1 gene, encoding a ζ-carotene desaturase essential for carotenoid biosynthesis, is involved in chloroplast development, photoprotection and retrograde signalling显示文摘Carotenoids, a class of natural pigments found in all photosynthetic organisms, are involved in a variety of physiologi-cal processes, including coloration, photoprotection, biosynthesis of abscisic acid (ABA) and chloroplast biogenesis.Although carotenoid biosynthesis has been well studied biochemically, the genetic basis of the pathway is not wellunderstood. Here, we report the characterization of two allelic Arabidopsis mutants, spontaneous cell death 1-1 (spcl-1)and spcl-2. The weak allele spcl-1 mutant showed characteristics of bleached leaves, accumulation of superoxide andmosaic cell death. The strong mutant allele spcl-2 caused a complete arrest of plant growth and development shortlyafter germination, leading to a seedling-lethal phenotype. Genetic and molecular analyses indicated that SPC1 encodesa putative ζ-carotene desaturase (ZDS) in the carotenoid biosynthesis pathway. Analysis of carotenoids revealed thatseveral major carotenoid compounds downstream of SPC1/ZDS were substantially reduced in spcl-1, suggesting thatSPC1 is a functional ZDS. Consistent with the downregulated expression of CAO and PORB, the chlorophyll contentwas decreased in spcl-1 plants. In addition, expression of Lhcb1.1, Lhcb1.4 and RbcS was absent in spcl-2, suggestingthe possible involvement of carotenoids in the plastid-to-nucleus retrograde signaling. The spcl-1 mutant also displaysan ABA-deficient phenotype that can be partially rescued by the externally supplied phytohormone. These results suggestthat SPC1/ZDS is essential for biosynthesis of carotenoids and plays a crucial role in plant growth and development.Haili Dong Yan Deng Jinye Mu Qingtao Lu Yiqin Wang Yunyuan Xu Chengcai Chu Kang Chong Congming Lu Jianru Zuo 2007Cell Research2007,17,5:8
8Precise Dating and Geological Significance of the Caledonian Shangyou Pluton in South Jiangxi Province显示文摘摘要:为 Shangyou 花岗石标明日期年龄的锆石虾是 464 吗??MAO Jianren ZENG Qingtao LI Zilong HU Qing ZHAO Xilin YE Haimin 2008Acta Geologica Sinica(English Edition)2008,82,2:6
9Elemental sulfur in northern South China Sea sediments and its significance显示文摘Elemental sulfur(ES) is one of the intermediates in the inorganic sulfur cycle and thus plays a key role in the fractionation of stable sulfur isotopes in different reservoirs and the marine environment. In this study, solid ES is discovered in sediments near the Jiulong Methane Reef in the northern South China Sea by scanning electron microscopy and Raman spectroscopy. Combining the morphology and distribution of ES, pyrite concentrations, and sulfur isotopes, we conclude that:(1) solid ES coexists with pyrite microcrystals and sulfide(oxyhydr)oxides as well as clay minerals, and they are mainly distributed on the surface of mineral aggregates;(2) ES mainly occurs within and near the sulfate-methane transition zone(SMTZ) despite little morphological diversity;(3) ES formation might be related to hydrogen sulfide oxidation and is therefore linked with fluctuations in the SMTZ. Within the SMTZ, hydrogen sulfide is produced and pyrite precipitates because of enhanced anaerobic oxidation of methane coupled with dissimilatory sulfate reduction. This enhances the efficiency of the inorganic sulfur cycle and provides favorable conditions for ES formation. The discovery of solid ES in sediments near the Jiulong Methane Reef suggests an important relationship with SMTZ fluctuations that could have implications for the evolution of methane hydrate in the South China Sea.LIN Qi WANG JiaSheng FU ShaoYing LU HongFeng BU QingTao LIN RongXiao SUN Fei 2015Science China Earth Sciences2015,58,12:6
10mTERF5 Acts as a Transcriptional Pausing Factor to Positively Regulate Transcription of Chloroplast psbEFLJ显示文摘RNA polymerase transcriptional pausing represents a major checkpoint in transcription in bacteria and metazoans,but it is unknown whether this phenomenon occurs in plant organelles.Here,we report that transcriptional pausing occurs in chloroplasts.We found that mTERF5 specifically and positively regulates the transcription of chloroplast psbEFLJ in Arabidopsis thaliana that encodes four key subunits of photosystem II.We found that mTERF5 causes the plastid-encoded RNA polymerase(PEP)complex to pause at psbEFLJ by binding to the+30 to+51 region of double-stranded DNA.Moreover,we revealed that mTERF5 interacts with pTAC6,an essential subunit of the PEP complex,although pTAC6 is not involved in the transcriptional pausing at psbEFLJ.We showed that mTERF5 recruits additional pTAC6 to the transcriptionally paused region of psbEFLJ,and the recruited pTAC6 proteins could be assembled into the PEP complex to regulate psbEFLJ transcription.Taken together,our findings shed light on the role of transcriptional pausing in chloroplast transcription in plants.Shunhua Ding Yi Zhang Zhi Hu Xiahe Huang Bohan Zhang Qingtao Lu Xiaogang Wen Yingchun Wang Congming Lu 2019Molecular Plant2019,12,9:6
113D printed silk-gelatin hydrogel scaffold with different porous structure and cell seeding strategy for cartilage regeneration显示文摘Hydrogel scaffolds are attractive for tissue defect repair and reorganization because of their human tissue-like characteristics.However,most hydrogels offer limited cell growth and tissue formation ability due to their submicron-or nano-sized gel networks,which restrict the supply of oxygen,nutrients and inhibit the proliferation and differentiation of encapsulated cells.In recent years,3D printed hydrogels have shown great potential to overcome this problem by introducing macro-pores within scaffolds.In this study,we fabricated a macroporous hydrogel scaffold through horseradish peroxidase(HRP)-mediated crosslinking of silk fibroin(SF)and tyramine-substituted gelatin(GT)by extrusion-based low-temperature 3D printing.Through physicochemical characterization,we found that this hydrogel has excellent structural stability,suitable mechanical properties,and an adjustable degradation rate,thus satisfying the requirements for cartilage reconstruction.Cell suspension and aggregate seeding methods were developed to assess the inoculation efficiency of the hydrogel.Moreover,the chondrogenic differentiation of stem cells was explored.Stem cells in the hydrogel differentiated into hyaline cartilage when the cell aggregate seeding method was used and into fibrocartilage when the cell suspension was used.Finally,the effect of the hydrogel and stem cells were investigated in a rabbit cartilage defect model.After implantation for 12 and 16 weeks,histological evaluation of the sections was performed.We found that the enzymatic cross-linked and methanol treatment SF5GT15 hydrogel combined with cell aggregates promoted articular cartilage regeneration.In summary,this 3D printed macroporous SF-GT hydrogel combined with stem cell aggregates possesses excellent potential for application in cartilage tissue repair and regeneration.Qingtao Li Sheng Xu Qi Feng Qiyuan Dai Longtao Yao Yichen Zhang Huichang Gao Hua Dong Dafu Chen Xiaodong Cao 2021Bioactive Materials2021,6,10:6
12An experimental study of shear strength of gas-hydrate-bearing core samples显示文摘The shear strength of gas-hydrate-bearing reservoirs is one of the most important parameters used to study mechanical properties of gas-hydrate-bearing reservoirs.The shear strength of gas-hydratebearing reservoirs changes with filling and cementation of gas hydrates,which will affect the wellbore and reservoir stability.Traditional shear tests could not be conducted on gas-hydrate-bearing core samples because the gas hydrates exist under a limited range of temperature and pressure conditions.This paper describes a novel shear apparatus for studying shear strength of gas-hydrate-bearing core samples under original reservoir conditions.The preparation of gas-hydrate-bearing core samples and subsequent shear tests are done in the same cell.Cohesion and internal friction angle of the core samples with different saturations of gas hydrates were measured with the apparatus.The effect of gas hydrates on the shear strength of reservoirs was quantitatively analyzed.This provides a foundation for studying wellbore and reservoir stability of gas-hydrate-bearing reservoirs.Zhang Weidong Ma Qingtao Wang Ruihe Ren Shaoran 2011Petroleum Science2011,8,2:5
13Decreased glutathione reductase2 leads to early leaf senescence in Arabidopsis显示文摘Glutathione reductase(GR) catalyzes the reduction of glutathione disulfide(GSSG) to reduced glutathione(GSH)and participates in the ascorbate-glutathione cycle, which scavenges H_2O_2. Here, we report that chloroplastic/mitochondrial GR2 is an important regulator of leaf senescence. Seed development of the homozygous gr2 knockout mutant was blocked at the globular stage. Therefore, to investigate the function of GR2 in leaf senescence, we generated transgenic Arabidopsis plants with decreased GR2 using RNAi. The GR2 RNAi plants displayed early onset of age-dependent and darkand H2O2-induced leaf senescence, which was accompanied by the induction of the senescence-related marker genes SAG12 and SAG13. Furthermore, transcriptome analysis revealed that genes related to leaf senescence, oxidative stress, and phytohormone pathways were upregulated directly before senescence in RNAi plants. In addition, H2O2 accumulated to higher levels in RNAi plants than in wild-type plants and the levels of H_2O_2 peaked in RNAi plants directly before the early onset of leaf senescence. RNAi plants showed a greater decrease in GSH/GSSG levels than wild-type plants during leaf development. Our results suggest that GR2 plays an important role in leaf senescence by modulating H_2O_2 and glutathione signaling in Arabidopsis.Shunhua Ding Liang Wang Zhipan Yang Qingtao Lu Xiaogang Wen Congming Lu 2016Journal of Integrative Plant Biology2016,58,1:5
14Synthesized high-silica hierarchical porous ZSM-5 and optimization of its reaction conditions in benzene alkylation with methanol显示文摘In our present work, the high-silica hierarchical porous ZSM-5 with appropriate Br(o|¨)nsted acidity and hierarchical porous structure was synthesized by sol-gel method for continuously catalytic conversion of benzene alkylation with methanol to xylene. The effects of temperature, pressure, benzene/methanol molar ratio and weight hour space velocity(WHSV) on the catalytic performance of the catalyst were investigated as well. As a result, the high-silica hierarchical porous ZSM-5 showed great performance as the yield of xylene was up to 41.1% under the optimum reaction conditions(500 ℃,0.1 MPa,M_(benzene)/M_(methanol)= 1:1.5 and WHSV=4 h 1), while the selectivity to by-product, ethylbenzene, was well suppressed(below 0.1%). In addition, the catalyst structure and properties were characterized by the means of XRD, IR, TPD,SEM, TEM and N_2 physical adsorption technologies.Jiayao Rui Jinghui Lyu Hualei Hu Qunfeng Zhang Qingtao Wang Xiaonian Li 2019Chinese Chemical Letters2019,30,3:5
15Chronology and cooling history of the Tianmenshan pluton in South Jiangxi Province and their geological significance显示文摘Geochronological studies on the crust-derived Tianmenshan pluton were undertaken by SHRIMP zircon U-Pb dating and Ar-Ar dating of biotite,muscovite and K-feldspar,giving a petrogenetic age of 167 Ma.Owing to the closure systems in different minerals,the cooling history of the pluton can be determined with an age-temperature diagram.The late hydrothermal event has been recognized,which is related probably with mineralization.In terms of the comparative geochronological and petrologic records,it is concluded that there are some constrains on tectonic evolution and that the formation of the Tianmenshan pluton proceeded in a transition period from Indosinian post-orogeny extension to strong compressive tectonics.And the timing of the hydrothermal event matches the compressive climax of the Yanshanian orogeny.The temporal gap between granite emplacement and wolframite mineralization could last 10-20 Ma owing to the low cooling rate of the pluton.ZENG Qingtao MAO Jianren HU Qing ZHAO Xilin YE Haimin 2008Chinese Journal Of Geochemistry2008,27,3:4
16Bilayered HA/CS/PEGDA hydrogel with good biocompatibility and self-healing property for potential application in osteochondral defect repair显示文摘The fabrication of osteochondral tissue engineering scaffolds comprised of different layers is a big challenge. Herein, bilayers comprised of double network hydrogels with or without nano hydroxyapatite(HAp) were developed by exploiting the radical reaction of poly(ethylene glycol) diacrylate(PEGDA)and the Schiff-base reaction of N-carboxyethyl chitosan(CEC) and oxidized hyaluronic acid sodium(OHA) for osteochondral tissue engineering. The bilayered osteochondral scaffold was successfully fabricated based on the superior self-healing property of both hydrogels and evaluated by scanning electron microscopy, macroscopic observation and mechanical measurements. In addition, the hydrogels exhibited good biocompatibility as demonstrated by the in vitro cytotoxicity and in vivo implantation tests. The results indicated that the bilayered hydrogel had great potential for application in osteochondral tissue engineering.Baihao You Qingtao Li Hua Dong Tao Huang Xiaodong Cao Hua Liao 2018Journal of Materials Science & Technology2018,34,6:4
17The Phytol Phosphorylation Pathway Is Essential for the Biosynthesis of Phylloquinone, which Is Required for Photosystem I Stability in Arabidopsis显示文摘Phytyl-diphosphate,在 tocopherol 和 phylloquinone 生合成作为普通底层提供 phytyl 一半,经由 phytol phosphorylation 源于 de novo isoprenoid 生合成或一条抢救小径。然而,很,很少为 phylloquinone 生合成对 phytyl 一半的角色和起源被知道。自从 VTE6, phytyl 磷酸盐 kinase,是为 phytol phosphorylation 的关键酶,我们描绘了 Arabidopsis vte6 异种在 photosystem 在 phylloquinone 生合成并且 phylloquinone 获得卓见进 phytyl 一半的角色我(希腊语的第二十三个字母) 生物的续生说。VTE6 猛烈异种 vte6-1 和 vte6-2 缺乏可检测的 phylloquinone,而在 VTE6 击倒的变异的 vte6-3 的 phylloquinone 内容是 90% 比那低在里面野类型。在 vte6 异种,希腊语的第二十三个字母功能被损害, PSI 建筑群的累积是有缺点的。希腊语的第二十三个字母核心子单元 PsaA/B 高效地在 vte6-3 被综合并且集合进 PSI 建筑群。然而,在装配希腊语的第二十三个字母建筑群的希腊语的第二十三个字母子单元的降级率比在在 vte6-3 是更快速的野类型。在 vte6-3,希腊语的第二十三个字母是更易受影响的加亮损坏比在里面野类型。我们的结果提供 phytol phosphorylation 小径为 phylloquinone 生合成是必要的,并且那 phylloquinone 为希腊语的第二十三个字母复杂稳定性被要求的第一条基因证据。Lei Wang Qingwei Li Aihong Zhang Wen Zhou Rui Jiang Zhipan Yang Huixia Yang Xiaochun Qin Shunhua Ding Qingtao Lu Xiaogang wen Congming Lu 2017Molecular Plant2017,10,1:4
18Viral and Antibody Kinetics of COVID-19 Patients with Different Disease Severities in Acute and Convalescent Phases:A 6-Month Follow-Up Study显示文摘Coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has spread rapidly around the world,posing a major threat to human health and the economy.Currently,long-term data on viral shedding and the serum antibody responses in COVID-19 patients are still limited.Herein,we report the clinical features,viral RNA loads,and serum antibody levels in a cohort of 112 COVID-19 patients admitted to the Honghu People’s Hospital,Hubei Province,China.Overall,5.36%(6/112)of patients showed persistent viral RNA shedding(>45 days).The peak viral load was higher in the severe disease group than in the mild group(median cycle threshold value,36.4 versus 31.5;P=0.002).For most patients the disappearance of IgM antibodies occurred approximately 4–6 weeks after symptoms onset,while IgG persisted for over 194 days after the onset of symptoms,although patients showed a 46%reduction in antibodies titres against SARS-CoV-2 nucleocapsid protein compared with the acute phase.We also studied18 asymptomatic individuals with RT-qPCR confirmed SARS-CoV-2 infection together with 17 symptomatic patients,and the asymptomatic individuals were the close contacts of these symptomatic cases.Delayed IgG seroconversion and lower IgM seropositive rates were observed in asymptomatic individuals.These data indicate that higher viral loads and stronger antibody responses are related to more severe disease status in patients with SARS-CoV-2 infection,and the antibodies persisted in the recovered patient for more than 6 months so that the vaccine may provide protection against SARS-CoV-2 infection.Xiaoyong Zhang Suwen Lu Hui Li Yi Wang Zhen Lu Zhihong Liu Qingtao Lai Yali Ji Xuan Huang Yongyin Li Jian Sun Yingsong Wu Xiaoning Xu Jinlin Hou 2020Virologica Sinica2020,35,6:4
19Response characteristics of array lateral logs and their primary inversion in reservoirs with fracture-induced anisotropy显示文摘为了识别,折断了水库并且决定他们有一个高定义的破裂参数穿 laterolog,我们与一个平行破裂组一起造了一个导致破裂的各向异性的形成模型。三维的有限元素方法被用来模仿数组 laterolog 的回答,然后主要倒置方法被利用。数字模拟证明当破裂间距是小的时,破裂组的数组 laterolog 反应与有宏观的电的 anisotropy 的形成的一样。数组 laterolog 的明显的抵抗力是近似与骨折相反地成正比孔。anisotropy 在折断的形成取决于破裂孔,它因此导致数组 laterolog 的反应变化。越高破裂剧降,越 larger 明显的抵抗力。当破裂剧降是低的时,深、浅的明显的抵抗力之间的差别是小的,并且当剧降高时,差别结果积极。破裂参数用 Marquardt 非线性的最少的广场方法被转换。结果,两个破裂孔和剧降在实际形成模型与参数显示出好匹配。这将在评估折断的水库支持数组 laterolog 的申请。Deng Shaogui Fan Yiren Li Zhiqiang Sun Qingtao 2011Petroleum Science2011,8,1:4
20Time-dependent surrounding soil pressure and mechanical response of tunnel lining induced by surrounding soil viscosity显示文摘A numerical simulation method of shield tunnel excavation is developed to capture the time-dependent deformation behaviour of surrounding soil. The simulation method consists of four parts:(i) an elastic-plastic-viscous constitutive model that can not only reasonably describe the viscous deformation behaviour of soil, but also appropriately calculate the plastic deformation under typical stress paths of excavation;(ii) simulation of main factors related to shield tunnel excavation, including the shield machine, face pressure, lining, grout behavior, and contacts between multiple media;(iii) a simulation procedure for excavation to reflect the process of shield tunnel excavation and achieve reasonable stress and strain fields at the end of the construction stage;(iv) a creep process that is used to investigate the long-term mechanical behaviours of the surrounding soil and tunnel lining. Taking the CK570H tunnel project in Taipei as the background, a numerical simulation is conducted by adopting the developed simulation method. Based on the simulation results, the radial and circumferential stresses acting on the lining, which are induced by the surrounding soil viscosity, are analysed. The rule of the mechanical response of lining, including its deformation, bending moment, and axial force, with time is revealed. On this basis, the long-term safety of the lining is evaluated.MIAO JinBo LU DeChun LIN QingTao KONG FanChao DU XiuLi 2021Science China(Technological Sciences)2021,64,11:3
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