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A higher order lattice BGK model for simulating some nonlinear partial differential equations

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Science China(Physics,Mechanics & Astronomy) 2009年第7期52卷 1053-1061页

作者： LAI HuiLin MA ChangFeng school of Mathematics and Computer Science Fujian Normal UniversityFuzhou 350007China

In this paper, we consider a one-dimensional nonlinear partial differential equation that has the form ut + αuux + βunux - γuxx + δuxxx = F(u). A higher order lattice Bhatnager-Gross-Krook (BGK) model with an amending-function is proposed. With the Chapman-Enskog expansion, different kinds of nonlinear partial differential equations are recovered correctly from the continuous Boltzmann equation. The numerical results show that this method is very effective.

关键词： nonlinear partial differential equation lattice Boltzmann model multi-scale technique Taylor series expansion Chapman-Enskog expansion

A Bombieri-type Theorem for Exponential Sums

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Acta Mathematica Sinica,English Series 2013年第10期29卷 1997-2012页

作者： Wei Li YAO Department of Mathematics College of SciencesShanghai University school of Mathematics Shandong University

Let fk（n） be the characteristic function of n with Ω（n） = k, and T k（x,α）=∑n≤xfk（n）e（nα）.The main purpose of this paper is to establish a Bombieri-type mean-value theorem for Tk（x, α）, via using the modified Huxley-Hooley contour and the large-sieve type zero-density estimate for Dirichlet L-functions. The result plays an important role in handling the enlarge major arcs when we try to solve the Waring-Goldbach type problem by the circle method

关键词： Zero-density estimate Huxley-Hooley contour .Bombieri-type theorem

An Approximation Algorithm for the Parallel-Machine Customer Order Scheduling with Delivery Time and Submodular Rejection Penalties

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Journal of the Operations Research Society of China 2024年第2期12卷 495-504页

作者： Hong-Ye Zheng Suo-Gang Gao Wen Liu Bo Hou school of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024HebeiChina

In this paper,we consider the parallel-machine customer order scheduling with delivery time and submodular rejection *** this problem,we are given m dedicated machines in parallel and n customer *** order has a delivery time and consists of m product types and each product type should be manufactured on a dedicated *** order is either rejected,in which case a rejection penalty has to be paid,or accepted and manufactured on the m dedicated *** objective is to find a solution to minimize the sum of the maximum delivery completion time of the accepted orders and the penalty of the rejected orders which is determined by a submodular *** design an LP rounding algorithm with approximation ratio of n+1 for this problem.

关键词： Order scheduling Delivery time Submodular rejection penalty Approximation algorithm

A new 2D Barium-organic Framework Built from 1H-Benzimidazole-5,6-dicarboxylate with Luminescent and Antibacterial Studies

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Chinese Journal of Structural Chemistry 2014年第3期33卷 387-394页

作者：许俊马德运覃亮 College of Medicine Jinan University school of Chemistry and Chemical Engineering Zhaoqing University

A new 2D barium-organic framework, [Ba2（Hbidc）2]n （1, Hbidc = 1H-benzimida- zole-5,6-dicarboxylate）, has been solvothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy, TGA, powder X-ray diffraction, and single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group Pī with α= 6.8785（14）, b = 9.4558（19）, c = 14.641（3） A, α = 86.22（3）, β = 82.27（3）, γ = 88.40（3）°, V = 941.4（3） A^3, Z = 2, Mr = 682.96, Dc = 2.409 g/cm^3, μ（MoKα） = 4.217 mm^-1, F（000） = 640, the final R = 0.0587 and wR = 0.1619 for 3030 observed reflections with I 〉 2σ（I）. Structural determination reveals that 1 exhibits an interesting 2D layer structure constructed by carboxylate groups of Hbidc ligands and shows good thermal stability （up to 400 ℃）. Solid-state 1 emits intense indigotin photoluminescence with fluorescence lifetime of 62.13 （408 nm） at room temperature. The H3bidc ligand and its barium complex have been screened for antibacterial activity against several bacteria strains, and the results are compared with the activity of penicillin.

关键词： barium-organic framework solvothermal synthesis,crystal structure luminescence antibacterial activity

Phase Transition and High Piezoactivity of Sr Doped Lead-Free （na0.53K0.422Li0.048）（nb0.89Sb0.06Wa0.05）O3 Ceramics

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Chinese Physics Letters 2008年第7期25卷 2573-2576页

作者：郑立梅王矜奉明保全亓鹏杜鹃 school of Physics State Key laboratory of Crystal Materials Shandong University Jinan 250100

Lead-free piezoelectric ceramics （na0.53K0.422Li0.048 ）（nb0.89Sb0.06 Ta0.05 ）03 （nKLnST）＋ x tool SrCO3 are prepared by conventional solid state sintering method. The specimens with pure perovskite structure show tetragonal phase at x 〈 0.01, and become pseudo-cubic phase at x 〉 0.02. A lattice parameter discontinuity is found in the specimens with 0.004 〈 x 〈 0.0075, along with a great improvement in piezoactivity. The 0.004 mol SrCO3 added nKLnST ceramics possesses outstanding performances of kp = 0.53, kt = 0.26, and d33=309 pC/n. Moreover, the Sr^2＋ modification inhibits the gra/n growth, decreases the Curie temperature, and induces a diffuse phase transition.

关键词： Phase Transition PIEZOELECTRIC PROPERTIES ceramic

Is Li-ESWT effective in diabetic patients with severe erectile dysfunction?

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Asian Journal of Andrology 2022年第5期24卷 521-524页

作者： Müslüm Ergün Osman Akyüz Department of Urology School of MedicineAtlas UniversityIstanbul 34200Turkey

noninvasive low-intensity extracorporeal shockwave treatment(Li-ESWT)has been widely used to treat erection *** is no clear information regarding either the selection of patients for the treatment or the treatment *** this study,we aimed to investigate the efficacy of extracorporeal shockwave therapy in diabetic patients with severe erectile dysfunction(International Index of Erectile Function-5[IIEF-5]scores of 5 to 7).Sixty-three diabetes mellitus patients with erectile dysfunction having IIEF-5 scores of 5 to 7 and not showing a recovery of potency despite phosphodiesterase type 5 inhibitor therapy for the past 6 months were included in the *** patients were evaluated based on their IIEF-5 scores and Erection Hardness Scale *** IIEF-5 score(mean±standard deviation[s.d.])increased from 5.29±1.67 to 5.56±1.85,with a difference of 0.27±0.18(P>0.05).The Erection Hardness Scale scores(mean±s.d.),on the other hand,increased from 1.46±0.50 to 1.48±0.50,with a difference of 0.02±0(P>0.05).In conclusion,the response to phosphodiesterase type 5 inhibitors did not change after extracorporeal shockwave treatment in diabetes mellitus patients with severe erectile dysfunction(IIEF-5 scores of 5 to 7).

关键词： diabetes mellitus International Index of Erectile Function-5 score low-intensity extracorporeal shockwave treatment severe erectile dysfunction

Effect of Sn on Corrosion Behavior of Ultra-pure 17 mass% Cr Ferritic Stainless Steels in Sulphuric Acid

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Journal of Iron and Steel Research International 2016年第10期23卷 1044-1053页

作者： Xiang-jun ZHAnG Fei GAO Zhen-yu LIU State Key Laboratory of Rolling and Automation Northeastern University school of Material and Metallurgy Northeastern University

The effect of Sn on corrosion behavior of ferritic stainless steels in 20mass% H2SO4 was investigated by alternating current and direct current electrochemical methods and gravimetric tests at 25 ℃.The results show that Sn can effectively improve general corrosion resistance of ferritic stainless steels in H2SO4,mainly due to highly raised hydrogen evolution overpotential which is in favour of strong suppression of hydrogen evolution reaction,and inhibitive effect of dissolved Sn^2＋ on elementary anodic *** increasing Sn content,the better corrosion resistance can be *** Electrochemical Impedance Spectroscopy（EIS）includes four time constants and can be perfectly fitted by equivalent circuit：Rs（CdlRct）（QadsRads（RL1（L1（RL2L2））））.

关键词： stainless steel tin sulphuric acid general corrosion hydrogen overpotential

Perioperative restricted fluid therapy preserves immunological function in patients with colorectal cancer

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World Journal of Gastroenterology 2014年第42期20卷 15852-15859页

作者： Hong-Ying Jie Ji-Lu Ye Hai-Hua Zhou Yun-Xiang Li Department of Intensive Care Unit Taizhou People’s Hospital Medical School of Nantong University Department of General Surgery Taizhou People’s Hospital Medical School of Nantong University Department of Anesthesiology Taizhou People’s Hospital Medical School of Nantong University

AIM: To investigate the effect of perioperative restricted fluid therapy on circulating CD4+/CD8+ T lymphocyte ratio, percentage of regulatory T cells (Treg) and postoperative complications in patients with colorectal... 详细信息

关键词： Colorectal cancer Restricted fluid therapy Standard fluid therapy Postoperative complications Immunological function

Coseismic slip distribution of 2009 L'Aquila earthquake derived from InSAR and GPS data

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Journal of Central South University 2012年第1期19卷 244-251页

作者： WAnG Yong-zhe ZHU Jian-jun OU Zi-qiang LI Zhi-wei XInG Xue-min school of Geosciences and Info-Physics Central South UniversityChangsha 410083China

To better understand the mechanism of the Mw6.3 L＇Aquila （Central Italy） earthquake occurred in 2009, global positioning system （GPS） and interferometric synthetic aperture radar （InSAR） data were used to derive the coseismic slip distribution of the earthquake fault. Firstly, based on the homogeneous elastic half-space model, the fault geometric parameters were solved by the genetic algorithm. The best fitting model shows that the fault is a 13.7 km×14.1 km rectangular fault, in 139.3° strike direction and 50.2° southwest-dipping. Secondly, fixing the optimal fault geometric parameters, the fault plane was extended and discretized into 16× 16 patches, each with a size of 1 kmx 1 krn, and the non-uniform slip distribution of the fault was inverted by the steepest descent method with an appropriate smoothing ratio based on the layered crustal structure model. The preferred solution shows that the fault is mainly a normal fault with slight right-lateral strike slip, the maximum slip of 1.01 m is located in the depth of 8.28 km, the average rake is -100.9°, and the total geodetic moment is about 3.34× 1018 n.m （Mw 6.28）. The results are much closer than previous studies in comparison with the seismological estimation. These demonstrate that the coseismic fault slip distribution of the L＇Aauila earthauake inverted by the crustal model considering layered characters is reliable.

关键词： L'Aquila earthquake interferometric synthetic aperture radar global positioning system (GPS) slip distribution