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Distribution of sterane maturity parameters in a lacustrine basin and their control factors:A case study from the Dongying Sag,East China

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Petroleum Science 2011年第3期8卷 290-301页

作者： Chen Zhonghong zha Ming Jin Qiang Ren yongjun College of geo-Resources and Information China University of Petroleum Qingdao Shandong 266555 China

Fifty samples from the source rocks in Member 3 and Member 4 of the Paleogene Shahejie Formation in the Bohai Bay Basin, East China, were analyzed to investigate the distribution, evolution of the molecular maturity ratios C29ββ/（ββ＋αα） and C2920S/（20S＋20R） and their control factors in the natural geological profile and sequence. The results showed that progressive changes in molecular maturity parameters are associated with major changes in thermal evolution of related biomarkers. Increases in the C29ββ/（ββ＋αα） and C2920S/（20S＋20R） ratios result from the difference in the relative rate between generation and thermal degradation of isomers involved. The samples from a hyper-saline environment below 3.5 km in which evaporitic rocks deposited shows high response of Sr/Ba, Sr/Ca, Fe/ Mn, Pr/n-C17, Ph/n-C18 and gammacerane and low response of Pr/Ph. There presents negative reversal of biomarker maturity C29ββ/（ββ＋αα, C29ββ/（ββ＋αα） and Ts/（Ts＋Ym） in the samples from hypersaline environment, reflecting that the gypsum- halite have negative effect on the isomerization of biomarker and thermal evolution of organic matter. The minerals in evaporites also retard the conventional thermal indicators including vitrinite reflectance （Ro） and pyrolysis peak temperature Tmax at the depth below 3.4 km （i.e. 〉3.4 km）, and these parameters also show the inhibition from overpressure in the range of 2.4-3.4 kin. This result will be helpful in the interpretation and application of molecular maturity parameters for similar saline lacustrine basins.

关键词： C29 24-ethyl cholestane biomarker thermal maturity parameters saline basins Dongying Sag

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Oscillatory squeeze flow through an Oldroyd-B fluid-saturated porous layer

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Applied Mathematics and Mechanics(English Edition) 2024年第11期45卷 2037-2054页

作者： yongjun JIAN School of Mathematics and Statistics Donghua UniversityShanghai201620China Institute for Nonlinear Science Donghua UniversityShanghai201620China

This study deals with the analytical investigation of oscillatory squeeze film flow through a Brinkman viscoelastic Oldroyd-B fluid-saturated porous layer subject to two vertically harmonically oscillatory *** validity of the present proposed analytical solutions is first demonstrated for the Newtonian fluids when bothΛ_(1)andΛ_(2)tend to zero by comparison with the previous *** demonstrate that an increase in the elasticity parameterΛ_(1)correlates with a rise in axial velocities,indicating that the relaxation timeΛ_(1)facilitates enhanced squeeze *** the case of squeeze film flow in porous layers,low oscillating frequencies exert minimal effects on axial velocities,independent of variations in the viscoelasticity parameterΛ_(1).However,at higher oscillating frequencies,axial velocities escalate with increasing the viscoelasticity parameterΛ_(1).Furthermore,the retardation timeΛ_(2)of the viscoelastic fluid shows no significant effect on the axial velocity,regardless of oscillating frequency changes in both pure fluids and porous layers.

关键词： Oldroyd-B fluid squeeze flow porous media oscillating boundary

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Production of anthocyanins in metabolically engineered microorganisms:Current status and perspectives

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Synthetic and Systems Biotechnology 2017年第4期2卷 259-266页

作者： Jian zha Mattheos A.g.Koffas Department of Chemical and Biological Engineering Center for Biotechnology and Interdisciplinary StudiesRensselaer Polytechnic InstituteTroyNYUSA Department of Biological Sciences Center for Biotechnology and Interdisciplinary StudiesRensselaer Polytechnic InstituteTroyNYUSA

Microbial production of plant-derived natural products by engineered microorganisms has achieved great success thanks to large extend to metabolic engineering and synthetic ***,the water-soluble colored pigments found in terrestrial plants that are responsible for the red,blue and purple coloration of many flowers and fruits,are extensively used in food and cosmetics industry;however,their current supply heavily relies on complex extraction from plant-based materials.A promising alternative is their sustainable production in metabolically engineered ***,we review the recent progress on anthocyanin biosynthesis in engineered bacteria,with a special focus on the systematic engineering modifications such as selection and engineering of biosynthetic enzymes,engineering of transportation,regulation of UDP-glucose supply,as well as process *** promising engineering strategies will facilitate successful microbial production of anthocyanins in industry in the near future.

关键词： Anthocyanin Enzyme engineering Metabolic engineering Microbial production

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HOMOMORPHISMS BETWEEN CHEVALLEY gROUPS OF TYPES C_nAND g_2 OVER FINITE FIELDS

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Chinese Annals of Mathematics,Series B 1997年第2期18卷 167-172页

作者： zha JIANgUO Department of Applied Mathematics Tongji UniversityShanghai 200092China

It is known that there exists an isogeny sort of Chevalley groups g (Σ, F) associated to any indecomposable root system Σ and any field F . In this paper the author determines all nontrivial homomorphisms from g(Σ, k) to g(Σ, K) when the root system Σ is of type C n or g 2 , and the fields k and K are finite fields of characteristic p .

关键词： Chevalley group Homomorphism Finite field

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“双一流”背景下地方高校学科建设困境及突围

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中国电化教育 2020年第1期 70-75页

作者：查永军扬州大学教育科学学院

学科建设是高校的基础性工作,为高校人才培养和专业建设提供着知识和智力支撑。我国"双一流"建设为入选高校学科发展提供着多方面的有力支持。该研究通过对地方高校学科建设特征的梳理分析,发现地方高校学科建设有着自身的独特性,具体包... 详细信息

学科建设是高校的基础性工作,为高校人才培养和专业建设提供着知识和智力支撑。我国"双一流"建设为入选高校学科发展提供着多方面的有力支持。该研究通过对地方高校学科建设特征的梳理分析,发现地方高校学科建设有着自身的独特性,具体包括:系统性、长期性、地方性和特色化等。研究发现:未入选"双一流"建设行列的地方高校处于财力不济,师资实力不强,学科平台少且层次低,知名度及社会认可度低,以及学校管理质态有待提高等困境。为了深入推进地方高校学科建设,需要学校决策者的大智慧和大手笔,为学科建设定好方向;更需要加强制度建设,营造利于学科发展的氛围;第三,需要积极彰显学科特色,实现错位竞争;实施协同发展战略,强化学科基地建设也是现实选择;最后,实施地方化与国际化策略,实现学科建设的顶天立地。

关键词： “双一流”建设地方高校学科建设学科发展

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Treating acute large vessel occlusion stroke:to bridge or not to bridge?

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Stroke & Vascular Neurology 2021年第3期6卷 324-327页

作者： Yunyun Xiong Yuesong Pan Raul g Nogueira Zeguang Ren Tudor g Jovin yongjun Wang Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Neurology Marcus Stroke and Neuroscience CenterGrady Memorial HospitalEmory University School of MedicineAtlantaGeorgiaUSA Neurosurgery Cleveland Clinic Martin HealthPort St LucieFloridaUSA Cooper Neurologic Institute Cooper University HospitalCamdenNew JerseyUSA Neurology Cooper Medical School of Rowan UniversityCamdenNew JerseyUSA

Hot debates exist regarding whether patients who had an acute large vessel occlusion stroke(LVOS)can skip tissue plasminogen activator(tPA)and go directly to thrombectomy in comprehensive stroke *** head-to-head randomised clinical trials(RCTs)of direct endovascular treatment(dEVT)versus bridge therapy(BT)with intravenous alteplase have been recently completed in the Asian *** DIRECT-MT(Direct Intraarterial Thrombectomy in Order to Revascularize Acute Ischemic Stroke Patients with Large Vessel Occlusion Efficiently in Chinese Tertiary Hospitals:a Multicenter Randomized Clinical Trial)Study randomly enrolled 656 patients who had an acute ischaemic stroke with anterior circulation LVOS across 41 large teaching hospitals in China to receive BT or dEVT within 4.5 hours after symptom onset.

关键词： acute occlusion Acute

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大数据与高校院系治理

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中国电化教育 2018年第1期 59-63页

作者：查永军扬州大学教育科学学院江苏扬州225002

大数据已经成为当下的时代背景,其"大""快""真"等特征对高校院系治理既是挑战又是机遇。该研究主要探究大数据与高校院系治理之间的适切性以及大数据对高校院系治理的具体作用。在对相关高校及国外实践借鉴和思考的基础上,提炼出推动我... 详细信息

大数据已经成为当下的时代背景,其"大""快""真"等特征对高校院系治理既是挑战又是机遇。该研究主要探究大数据与高校院系治理之间的适切性以及大数据对高校院系治理的具体作用。在对相关高校及国外实践借鉴和思考的基础上,提炼出推动我国高校将大数据用于院系治理的建议。在大数据背景下,高校需应时而动,及时做出决策,在观念、制度、行动等层面切实有效的建设和使用好大数据平台;重视大数据对院系治理的时代价值,提升人员大数据建设和运用水平;在构建院系大数据平台基础上,将大数据充分用于高校院系决策、院系运行常态化监管和院系评估等工作。

关键词：大数据院系治理信息素养

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Time periodic electroosmotic flow of micropolar fluids through microparallel channel

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Applied Mathematics and Mechanics(English Edition) 2016年第6期37卷 769-786页

作者： zhaodong DINg yongjun JIAN Liangui YANg School of Mathematical Sciences Inner Mongolia University

The time periodic electroosmotic between two infinitely extended microparallel flow of an incompressible micropolar fluid plates is studied. The analytical solutions of the velocity and microrotation are derived under the Debye-Hiickel approximation. The effects of the related dimensionless parameters, e.g., the micropolar parameter, the frequency, the electrokinetic width, and the wall zeta potential ratio of the upper plate to the lower plate, on the electroosmotic velocity and rnicrorotation are investigated. The results show that the amplitudes of the velocity and the volume flow rate will drop to zero when the micropolar parameter increases from 0 to 1. The effects of the electrokinetic width and the frequency on the velocity of the micropolar fluid are similar to those of the Newtonian fluid. However, the dependence of the microrotation on the related parameters mentioned above is complex. In order to describe these effects clearly, the dimensionless microrotation strength and the penetration depth of the microrotation are defined, which are used to explain the variation of the microrotation. In addition, the effects of various parameters on the dimensionless stress tensor at the walls are studied.

关键词： micropolar fluid electroosmotic flow microrotation strength penetration depth

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我国大学学术组织科层化及应对

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中国高教研究 2009年第3期 46-46,47-48页

作者：查永军华中科技大学教科院扬州大学教科院副教授湖北武汉430074

我国大学学术组织在学术事务管理中呈现科层化倾向。学术组织科层化产生了多方面的影响,具体包括积极和消极两个方面的后果。之所以出现学术组织科层化倾向是和强势行政权力以及行政管理模式向学术组织的不断渗透有关。同时,我国大学学... 详细信息

我国大学学术组织在学术事务管理中呈现科层化倾向。学术组织科层化产生了多方面的影响,具体包括积极和消极两个方面的后果。之所以出现学术组织科层化倾向是和强势行政权力以及行政管理模式向学术组织的不断渗透有关。同时,我国大学学术民主管理理念根基不牢也是重要因素。完善大学制度,强化教授集体权力,严格学术标准,唤醒学者学术操守等均是应对学术组织科层化消极影响的重要措施。

关键词：学术组织学术管理行政权力科层化

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Performances of fissured red sandstone after thermal treatment with constant-amplitude and low-cycle impacts

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Journal of Rock Mechanics and geotechnical Engineering 2024年第2期16卷 561-587页

作者： yongjun Chen Tubing Yin P.g.Ranjith Xibing Li Qiang Li Dengdeng Zhuang School of Resources and Safety Engineering Central South UniversityChangsha410083China Department of Civil Engineering Monash UniversityMelbourne3800Australia Oulu Mining School University of OuluOuluFI-90014Finland

In the engineering practices,it is increasingly common to encounter fractured rocks perturbed by temperatures and frequent dynamic *** this paper,the dynamic behaviors and fracture characteristics of red sandstone considering temperatures(25℃,200℃,400℃,600℃,and 800℃)and fissure angles(0°,30°,60°,and 90°)were evaluated under constant-amplitude and low-cycle(CALC)impacts actuated by a modified split Hopkinson pressure bar(SHPB)***,fracture morphology and second-order statistics within the grey-level co-occurrence matrix(gLCM)were examined using scanning electron microscopy(SEM).Meanwhile,the deep analysis and discussion of the mechanical response were conducted through the synchronous thermal analyzer(STA)test,numerical simulations,one-dimensional stress wave theory,and material *** multiple regression models between response variables and interactive effects of independent variables were established using the response surface method(RSM).The results demonstrate the fatigue strength and life diminish as temperatures rise and increase with increasing fissure angles,while the strain rate exhibits an inverse ***,the peak stress intensification and strain rate softening observed during CALC impact exhibit greater prominence at increased fissure *** failure is dominated by tensile damage with concise evolution paths and intergranular cracks as well as the compressor-crushed zone which may affect the failure mode after 400℃.The second-order statistics of gLCM in SEM images exhibit a considerable dependence on the ***,thermal damage dominated by thermal properties controls the material structure and wave impedance and eventually affects the incident wave *** tensile wave reflected from the fissure surface is the inherent mechanism responsible for the angle effect exhibited by the fatigue strength and ***,the peak stress intensification and strain rate softening during impact are determ

关键词： Red sandstone Temperature Fissure Constant-amplitude and low-cycle(CALC) impact Fatigue failure Response surface method(RSM)

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