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CAVITATION INCEPTION OF GATE SLOTS

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Journal of Hydrodynamics 1993年第2期5卷 30-44页

作者： jin, tailai Lin, Changgeng Liu, Xiaomei Inst of Water Conservancy and Hydroelectric Power Research Beijing China

Starting with field investigation this paper presented a comprehensive review of the hydraulic design and performance of gate slots in 85 existing projects covering 158 gates of various dimension and operating head. Systematic model tests were conducted in a water tunnel to optimize the configuration of gate slots. Main parameters affecting cavitation inception were studied, such as the ratio of width to depth, relative offset, the slope of side wall, as well as the radius of curvature of slot's corner. The scale effects of cavitation modelling were preliminarily verified. The conformity between model studies and prototype inspections is quite agreeable. Conclusion and suggestion were made to meet the demand of hydraulic design of gate slots.

关键词： Cavitation Fluid structure interaction Hydraulic gates

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工业纯钛在特高温度下的氧化行为研究

稀有金属材料与工程 2005年第12期34卷 1998-2001页

作者：金泰来魏建锋顾兆林赵永庆常辉西安交通大学陕西西安710049 西北有色金属研究院陕西西安710016

通过Gleeble-1500热模拟机研究了在特高温度下工业纯钛的氧化行为。结果表明,随着氧化温度的升高和保温时间的延长,氧化增重持续增加：特高温氧化产生了多层氧化膜,氧通过破损的外层氧化膜通道向较致密的内层氧化膜扩散及向金属基体渗透... 详细信息

通过Gleeble-1500热模拟机研究了在特高温度下工业纯钛的氧化行为。结果表明,随着氧化温度的升高和保温时间的延长,氧化增重持续增加：特高温氧化产生了多层氧化膜,氧通过破损的外层氧化膜通道向较致密的内层氧化膜扩散及向金属基体渗透,实现了工业纯钛的整个特高温氧化过程。

关键词：工业纯钛特高温氧化氧化层

Shor's algorithm does not factor large integers in the presence of noise

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Science China(Information Sciences) 2024年第7期67卷 305-320页

作者： jin-Yi CAI College of Letters and Science University of Wisconsin

We consider Shor's quantum factoring algorithm in the setting of noisy quantum gates. Under a generic model of random noise for(controlled) rotation gates, we prove that the algorithm does not factor integers of the form pq when the noise exceeds a vanishingly small level in terms of n—the number of bits of the integer to be factored, where p and q are from a well-defined set of primes of positive density. We further prove that with probability 1-o(1) over random prime pairs(p, q), Shor's factoring algorithm does not factor numbers of the form pq, with the same level of random noise present.

关键词： random noise Shor's algorithm rotation gates quantum computing prime factorization

Semi-analytical Solutions for Wellbores with Graded Skin Zones in Poroelastic Media

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Acta Mechanica Solida Sinica 2024年第3期37卷 385-395页

作者： Zhiqiang Fan Zhihe jin School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China Department of Mechanical Engineering University of MaineOronoME04469USA

In analyzing the complex interaction between the wellbore and the reservoir formation,the hydromechanical properties of the region proximal to the wellbore,referred to as the“wellbore skin zone”,play a pivotal role in determining flow dynamics and the resulting formation *** models of the wellbore skin zone generally assume a constant permeability throughout,resulting in a sharp permeability discontinuity at the skin-reservoir *** paper introduces a model for a wellbore with a continuously graded skin zone of finite thickness within a poroelastic *** solutions are derived using the Laplace transform method,addressing both positive and negative skin *** results are presented to illustrate the effects of graded permeability/skin zone thickness on pore pressures and stresses around a *** results highlight a distinct divergence in stress and pore pressure fields when comparing wellbores with negative skin zones to those with positive skin zones or no skin at all.

关键词： Poroelastic Graded permeability Analytical solution Wellbore Skin zone

Advanced Algorithm for Parameters Estimation of Negative Binomial Distribution with High Dimensional Sparse Group Structure

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Journal of Systems Science & Complexity 2024年第5期37卷 2173-2195页

作者： LI Meiqi jin Baisuo School of Management University of Science and Technology of ChinaHefei 230000China

Negative binomial regression is a powerful technique for modeling count data,particularly when dealing with ***,estimating the parameters for large-dimensional sparse models is challenging due to the complexity of optimizing the mean and dispersion parameter of the negative binomial *** address this issue,the authors propose a novel approach that employs two iterations of the majorize-minimize(MM)algorithm,one for estimating the dispersion parameter and the other for estimating the mean *** approaches improve the convergence speed and stability of the *** authors also use group penalty for variable selection,which enhances the accuracy and efficiency of the *** proposed method provides an explicit solution,simplifies the iteration process,and maintains good stability while ensuring algorithm ***,the authors apply the proposed algorithm to the zero-inflated model and demonstrate its promising predictive performance on specific data *** research has important implications for count data modeling and analysis in various fields,such as data mining,machine learning,and bioinformatics.

关键词： Group structure majorize-minimize(MM) negative binomial

From 'glass basins' to 'glass barriers'

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National Science Review 2024年第6期11卷 95-96页

作者： Yuliang jin Institute of Theoretical Physics Chinese Academy of Sciences School of Physical Sciences University of Chinese Academy of Sciences Center for Theoretical Interdisciplinary Sciences Wenzhou InstituteUniversity of Chinese Academy of Sciences

If a supercooled liquid is cooled rapidly to avoid crystallization, a glass is *** this procedure, the viscosity can increase by more than 10 orders of magnitude over a small temperature range near the glass transitio... 详细信息

关键词： LIQUIDS

Combined Treatment with Bojungikgi-tang(Buzhong Yiqi Decoction)and Riluzole Attenuates Cell Death in TDP-43-Expressing Cells

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Chinese Journal of Integrative Medicine 2024年第7期30卷 616-622页

作者： Eun jin Yang Department of KM Science Research Korea Institute of Oriental MedicineDaejeonYuseong-gu34054Republic of Korea

Objective To examine the effect of combined treatment with Bojungikgi-tang(BJIGT,Buzhong Yiqi Decoction)and riluzole(RZ)in transactive response DNA-binding protein 43(TDP-43)stress granule(SG)cells,a amyotrophic lateral sclerosis(ALS)cell line using transcriptomic and molecular *** TDP-43 SG cells were pretreated with BJIGT(100µg/mL),RZ(50µmol/L),and combined BJIGT(100µg/mL)/RZ(50µmol/L)for 6 h before treatment with lipopolysaccharide(LPS,200µmol/L).Cell viability assay was performed to elucidate cell toxicity in TDP-43 SC cells using a cell-counting kit-8(CCK8)assay *** expression levels of cell death-related proteins,including Bax,caspase 1,cleaved caspase 3 and DJ1 in TDP-43 SG cells were examined by Western blot *** autophagy-related proteins,including pmTOR/mTOR,LC3b,P62,ATG7 and Bcl-2-associated athanogene 3(Bag3)were investigated using immunofluorescence and immunoblotting *** Cell viability assay and Western blot analysis showed that combined treatment with BJIGT and RZ suppressed LPS-induced cell death and expression of cell death-related proteins,including Bax,caspase 1,and DJ1(P<0.05 or P<0.01).Immunofluorescence and immunoblotting assays showed that combined treatment with BJIGT and RZ reduced LPS-induced formation of TDP-43 aggregates and regulated autophagy-related protein levels,including p62,light chain 3b,Bag3,and ATG7,in TDP-43-expressing cells(P<0.05 or P<0.01).Conclusion The combined treatment of BJIGT and RZ might reduce inflammation and regulate autophagy dysfunction in TDP-43-induced ALS.

关键词： Bojungikgi-tang Buzhong Yiqi Decoction transactive response DNA-binding protein 43 autophagy oxidative stress amyotrophic lateral sclerosis

Modeling and Validation of Diamagnetic Rotor Levitated by Permanent Magnetics

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 224-235页

作者： Yuanping Xu Yue Zhang jin Zhou Chaowu jin College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

As an innovative,low-power consuming,and low-stiffness suspension approach,the diamagnetic levitation technique has attracted considerable interest because of its potential applicability in miniaturized mechanical *** foundation of a diamagnetic levitation system is mathematical modeling,which is essential for operating performance optimization and stability ***,few studies on systematic mathematical modeling have been *** this study,a systematic mathematical model for a disc-shaped diamagnetically levitated rotor on a permanent magnet array is *** on the proposed model,the magnetic field distribution characteristics,diamagnetic levitation force characteristics(i.e.,levitation height and stiffness),and optimized theoretical conditions for realizing stable levitation are *** are conducted to verify the feasibility of the proposed mathematical *** predictions and experimental results indicate that increasing the levitation height enlarges the stable ***,with a further increase in the rotor radius,the stable regions of the rotor gradually diminish and even ***,when the levitation height is fixed,a moderate rotor radius permits stable *** study proposes a mathematical modeling method for a diamagnetic levitation system that has potential applications in miniaturized mechanical systems.

关键词： Diamagnetic levitation Magnetic levitation Rotor Modeling Validation Stability

Mobility of rhenium and selenium during chemical weathering and their implication for petrogenic organic carbon oxidation

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Science China Earth Sciences 2024年第3期67卷 740-750页

作者： Yuhong ZHANG jin WANG Yuanxin QU Chao ZHU Zhangdong jin State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China University of Chinese Academy of Sciences Beijing 100049China Xi'an Institute for Innovative Earth Environment Research Xi'an 710061China Institute of Global Environmental Change Xi'an Jiaotong UniversityXi'an 710049China

The oxidative weathering of petrogenic organic carbon(OC_(petro)) is an important source of carbon dioxide(CO_(2)) into the atmosphere on geological timescales and significantly influences the carbon cycle and global climate change. However, at present, a robust proxy to assess OC_(petro)oxidation is lacking. Riverine rhenium(Re) has emerged as a potential proxy to trace OC_(petro)oxidation, but little is known about Re sources and its relationship with OC_(petro)oxidation. To better understand the robustness of this proxy, we analyzed a shale weathering profile from the early Cambrian Shuijingtuo Formation in Chengkou County, Chongqing City, to address the mobility of Re and selenium(Se) and their relationship with the oxidation of OC_(petro)by analyses of the elemental variation and sequential extraction. The results showed that the chemical index of alteration(CIA)increases from the fresh bedrock to the weathered sections, indicating enhanced weathering intensity. Based on the sequential extraction and mass transfer coefficients(τ), Re and Se mainly exist in the organic phase of shale and are paired lost with OC_(petro) during weathering, with no obvious correlation with sulfide minerals. Furthermore, the different proportions of Re and Se loss with OC_(petro) loss can be attributed to their different geochemical behaviors during weathering. Our study supports Re as a robust proxy to trace OC_(petro) oxidation, whereas Se is the potential one. In the future, combined studies on various sedimentary rock profiles with catchment basins are needed to determine the sources of riverine Re and Se and their relationships with OC_(petro) oxidation.

关键词： Rhenium and selenium Shale Mobility OC_(petro) Chemical weathering