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Embedding Derivatives and Integration Operators on Hardy Type Tent Spaces

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Acta Mathematica Sinica,English Series 2022年第6期38卷 1069-1093页

作者： mao fa wang Lv ZHOU School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

In this paper,we completely characterize the positive Borel measuresμon the unit ball B_(n)such that the differential type operator R^(m)of order m∈N is bounded from Hardy type tent space HT_(q,α)^(p)(B_(n))into L^(s)(μ)for full range of p,q,s,α.Subsequently,the corresponding compact description of differential type operator R^(m)is also *** an application,we obtain the boundedness and compactness of integration operator J_(g)from HT_(q,α)^(p)(B_(n))toHT_(s,β)^(t)(B_(n)),and the methods used here are adaptable to the Hardy spaces.

关键词： Embedding derivative integration operator Hardy type tent space Carleson measure

Integration Operators on Spaces of Dirichlet Series

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Acta Mathematica Sinica,English Series 2023年第10期39卷 1919-1938页

作者： Jia Le CHEN mao fa wang School of Mathematics and Statistics Shaanxi Normal UniversityXi’an 710119P.R.China School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

We first study the Volterra operator V acting on spaces of Dirichlet *** prove that V is bounded on the Hardy space H_(0)^(p)for any 0 详细信息

We first study the Volterra operator V acting on spaces of Dirichlet *** prove that V is bounded on the Hardy space H_(0)^(p)for any 0

关键词： Integration operator Dirichlet series Hardy space Bergman space

Complex Symmetric C0-semigroups on A^2(C+)

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Acta Mathematica Sinica,English Series 2020年第10期36卷 1171-1182页

作者： Kai Kai HAN mao fa wang School of Mathematics and Statistics Hebei University of Economics and BusinessShijiazhuang 050061P.R.China School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

In this paper,we study complex symmetric C0-semigroups on the Bergman space A^2(C+) of the right half-plane C+.In contrast to the classical case,we prove that the only involutive composition operator on A^2(C+) is the identity operator,and the class of J-symmetric composition operators does not coincide with the class of normal composition *** addition,we divide semigroups{φt}of linear fractional self-maps of C+into two *** show that the associated composition operator semigroup{Tt}is strongly continuous and identify its infinitesimal *** an application,we characterize Jσ-symmetric C0-semigroups of composition operators on A^2(C+).

关键词： C0-semigroup Bergman space composition operator complex symmetry

Compactness of Product Operators on the Bergman Space

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Acta Mathematica Sinica,English Series 2005年第4期21卷 723-732页

作者： mao fa wang Pei De LIU Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 P. R. China Wuhan University Wuhan 430072 P. R. China

In this paper, we study the compactness of the product of a composition operator with another one＇s adjoint on the Bergman space. Some necessary and sufficient conditions for such operators to be compact are given.

关键词： Bergman space Composition operator Compact operator Angular derivative

Optimization of the co-closing law of guide vanes and blades for bulb turbines based on CFD

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Journal of Hydrodynamics 2024年第2期36卷 363-377页

作者： Hui Liu Yun-fa Lin Yong-guang Cheng Song Xue mao-jia Tang Jian Zhang Jia-yi fan State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan430072China Dongfang Electric Machinery Co. Ltd.Deyang618000China

The load rejection transient process of bulb turbine units is critical to safety of hydropower stations,and determining appropriate closing laws of guide vanes(GVs)and runner blades(RBs)for this process is of *** this study,we proposed a procedure to optimize the co-closing law of GVs and RBs by using computational fluid dynamics(CFD),combined with the design of experiment(DOE)method,approximation model,and genetic optimization *** sensitivity of closing law parameters on the histories of head,speed,and thrust was analyzed,and a two-stage GVs’closing law associating with a linear RBs’closing law was *** results show that GVs dominate the transient characteristics by controlling the change of *** GVs’first-stage closing speed while shortening first-stage closing time can not only significantly reduce the maximum rotational speed but also suppress the water hammer pressure;slowing GVs’second-stage closing speed is conducive to controlling the maximum reverse axial *** directly affect the runner *** RBs’closing speed can further reduce the rotational speed and the maximum reverse axial *** safety margin of each control parameter,flow patterns,and pressure pulsations of a practical hydropower station were all improved after optimization,demonstrating the effectiveness of this method.

关键词： Bulb turbine load rejection transient process double regulation closing law optimization computational fluid dynamics(CFD)

The coupling control of biological precursors and environmental factors onβ-carotane enrichment in alkaline lacustrine source rocks:A case study from the Fengcheng formation in the western Junggar Basin,NW China

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Petroleum Science 2024年第2期21卷 836-854页

作者： mao-Guo Hou Ming Zha Hua Liu Hai-Lei Liu Jiang-Xiu Qu Ablimit Imin Xiu-Jian Ding Zhong-fa Jiang School of Geosciences China University of PetroleumQingdaoShandong266580China Research Institute of Exploration and Development Xinjiang Petroleum Administration BureauKaramayXinjiang834000China

The organic-rich mudstones and dolostones of the Permian Fengcheng Formation(Fm.)are typically alkaline lacustrine source rocks,which are typified by impressively abundantβ-*** β-carotane has been well acknowledged as an effective indicator of biological sources or depositional ***,the specific biological sources of β-carotane and the coupling control of biological sources and environmental factors on the enrichment of β-carotane in the Fengcheng *** *** on a comprehensive investigation of the bulk,molecular geochemistry,and organic petrology of sedimentary rocks and the biochemistry of phytoplankton in modern alkaline lakes,we proposed a new understanding of the biological precursors of β-carotane and elucidated the enrichment mechanism of β-carotane in the Fengcheng *** results show that the biological precursors crucially control the enrichment of β-carotane in the Fengcheng *** haloalkaliphilic cyanobacteria are the primary biological sources of β-carotane,which is suggested by a good positive correlation between the 2-methylhopane index,7-+8-methyl heptadecanes/C_(max),C_(29%),and β-carotane/C_(max)in sedimentary rocks and the predominance of cyanobacteria with abundantβ-carotene in modern alkaline *** enrichment of β-carotane requires the reducing condition,and the paleoredox state that affects the enrichment of β-carotane appears to have a *** paleoclimate conditions do not considerably impact the enrichment of β-carotane,but they have some influence on the water's paleosalinity by affecting evaporation and *** it does not directly affect the enrichment of β-carotane in the Fengcheng Fm.,paleosalinity does have an impact on the cyanobacterial precursor supply and the preservation conditions.

关键词： β-carotane enrichment Cyanobacterial input Environmental impact Alkaline lacustrine source rocks The Fengcheng formation

Evaluation of microRNA expression profiles in human sperm frozen using permeable cryoprotectant-free droplet vitrification and conventional methods

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Asian Journal of Andrology 2024年第4期26卷 366-376页

作者： Li-Xin Zhang Jing mao Yan-Dong Zhou Guang-Yao mao Run-fa Guo Hong-Shan Ge Xia Chen Department of Histology and Embryology Medical SchoolNantong UniversityNantong 226001China Department of Reproductive Medicine The Affiliated Taizhou People’s Hospital of Nanjing Medical UniversityTaizhou School of Clinical MedicineNanjing Medical UniversityTaizhou 225300China.

For sperm cryopreservation,the conventional method,which requires glycerol,has been used for a long *** addition,the permeable cryoprotectant-free vitrification method has been continuously *** the differences of cryopreservation effects between the two methods have being studied,differences in microRNA(miRNA)profiles between them remain *** this study,we investigated the differences in miRNA expression profiles among conventional freezing sperm,droplet vitrification freezing sperm and fresh human *** also analyzed the differences between these methods in terms of differentially expressed miRNAs(DEmiRs)related to early embryonic development and paternal *** results showed no significant differences between the cryopreservation methods in terms of sperm motility ratio,plasma membrane integrity,DNA integrity,mitochondrial membrane potential,acrosome integrity,and ultrastructural ***,sperm miRNA-sequencing showed differences between the two methods in terms of the numbers of DEmiRs(28 and 19 with vitrification using a nonpermeable cryoprotectant and the conventional method,respectively)in postthaw and fresh sperm *** related to early embryonic development and paternal epigenetics mainly included common DEmiRs between the *** results showed that the differences between conventional freezing and droplet vitrification were minimal in terms of miRNA expression related to embryonic development and *** in sperm miRNA expression due to freezing are not always detrimental to embryonic *** study compared differences in miRNA expression profiles before and after cryopreservation between cryopreservation by conventional and vitrification *** offers a new perspective to evaluate various methods of sperm cryopreservation.

关键词： cryopreservation cryoprotectant-free vitrification early embryonic development paternal epigenetic inheritance sperm miRNAs sucrose

Investigation of gravity influence on EOR and CO_(2) geological storage based on pore-scale simulation

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Petroleum Science 2024年第2期21卷 987-1001页

作者： Yong-mao Hao Gui-Cheng Wu Zong-fa Li Zhong-Hui Wu Yong-Quan Sun Ran Liu Xing-Xing Li Bo-Xin Pang Nan Li Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina School of Petroleum Engineering Yangtze UniversityWuhan430100HubeiChina Dongsheng Jinggong Petroleum Development Group Co. LtdShengli Oilfield CompanySINOPECDongying257001ShandongChina

Gravity assistance is a critical factor influencing CO_(2)-Oil mixing and miscible flow during EOR and CO_(2)geological *** on the Navier-Stokes equation,component mass conservation equation,and fluid property-composition relationship,a mathematical model for pore-scale CO_(2) injection in oilsaturated porous media was developed in this *** model can reflect the effects of gravity assistance,component diffusion,fluid density variation,and velocity change on EOR and CO_(2) *** nonhomogeneous porous media,the gravity influence and large density difference help to minimize the velocity difference between the main flow path and the surrounding area,thus improving the oil recovery and CO_(2) *** CO_(2) injection angles and oil-CO_(2) density differences can increase the oil recovery by 22.6% and 4.2%,respectively,and increase CO_(2) storage by 37.9% and 4.7%,*** diffusion facilitates the transportation of the oil components from the low-velocity region to the main flow path,thereby reducing the oil/CO_(2) concentration difference within the porous *** diffusion can increase oil recovery and CO_(2) storage by 5.7% and 6.9%,*** addition,combined with the component diffusion,a low CO_(2) injection rate creates a more uniform spatial distribution of the oil/CO_(2) component,resulting in increases of 9.5% oil recovery and 15.7% CO_(2) storage,*** study provides theoretical support for improving the geological CO_(2) storage and EOR processes.

关键词： Gravity Flow simulation CO_(2)-oil mixing Enhanced oil recovery(EOR) Geological storage

Early systemic anticoagulation reduces hospital readmission in acute necrotizing pancreatitis patients:A retrospective cohort study

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 77-82页

作者： Wen-Jian mao Jing Zhou Guo-Fu Zhang fa-Xi Chen Jing-Zhu Zhang Bai-Qiang Li Lu Ke Wei-Qin Li Department of Critical Care Medicine Jinling HospitalNanjing Medical UniversityNanjing 210002China Department of Critical Care Medicine Jinling HospitalMedical School of Nanjing UniversityNanjing 210002China National Institute of Healthcare Data Science Nanjing UniversityNanjing 210010China

Background:Early systemic anticoagulation(SAC)is a common practice in acute necrotizing pancreatitis(ANP),and its impact on in-hospital clinical outcomes had been ***,whether it affects long-term outcomes is *** study aimed to evaluate the effect of SAC on 90-day readmission and other long-term outcomes in ANP ***:During January 2013 and December 2018,ANP patients admitted within 7 days from the onset of abdominal pain were *** primary outcome was 90-day readmission after *** proportional-hazards regression model and mediation analysis were used to define the relationship between early SAC and 90-day ***:A total of 241 ANP patients were enrolled,of whom 143 received early SAC during their hospitalization and 98 did *** who received early SAC experienced a lower incidence of splanchnic venous thrombosis(SVT)[risk ratio(RR)=0.40,95%CI:0.26-0.60,Pfactor for 90-day readmission after adjusting for potential confounders with a hazard ratio of 0.57(95%CI:0.34-0.96,P=0.04).Mediation analysis showed that SVT mediated 37.0%of the early SAC-90-day readmission ***:The application of early SAC may reduce the risk of 90-day readmission in the survivors of ANP patients,and reduced SVT incidence might be the primary contributor.

关键词： Anticoagulation Splanchnic venous thrombosis Acute necrotizing pancreatitis Readmission Long-term outcomes