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CHARACTERIZATIONS ON THE THIXOTROPY-LOOP TESTS USING UCM MODEL WITH A RATE-TYPE KINETIC EQUATION

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Chinese Journal of Polymer Science 2006年第6期24卷 609-617页

作者： shu-xin huang Chuan-jing Lu Department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200030 China

The theoretical characterizations on the triangular-form thixotropy-loop tests of an LDPE melt （PE-FSB- 23D022/Q200） were conducted in the present paper by using a new thixotropy model, which is constituted by the upper convected Maxwell model and a rate-type kinetic equation. The new thixotropic Maxwell model can partially describe well three reported thixotropy-loop experiments by comparison with the previous calculations of the variant form of the thixotropy-type huang model. It is noted that the stress deviations between the experiments and the predictions of the new thixotropic Maxwell model are much slighter than those deviations obtained by using the variant huang model at the same condition, although both models include five parameters. The constitution of the new thixotropic Maxwell model is more reasonable than that of the variant huang model.

关键词： Thixotropy-loop tests Theoretical characterization Thixotropy models.

Note on Filon-type integration for higher order exponential time differencing methods in stiff systems

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Journal of Central South University of Technology 2005年第Z1期12卷 298-303页

作者： XIANG shu-huang School of Mathematical Science and Computing Technology Central South University Changsha 410083 China

The Filon-type quadrature is efficient for highly oscillatory functions - Fourier transforms. Based on Cox and Matthews' ETD schemes, the higher order single step exponential time differencing schemes are presented based on the Filon-type integration and the A-stability of the two-order Adams-Bashforth exponential time differencing scheme is considered. The effectiveness and accuracy of the schemes is tested.

关键词： exponential time differencing method stiff system Filon method Runge-Kutta method

The Effect of NMR Setting Parameters on Molecular Weight Determination of Polyether Diols

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Chinese Journal of Polymer Science 2024年第11期42卷 1730-1737,I0010页

作者： shu-Jie huang Xiao-Hong Li Ying-Feng Tu Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials State and Local Joint Engineering Laboratory for Novel Functional Polymeric MaterialsCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou215123China

Nuclear magnetic resonance(NMR)is an advanced technique for the molecular weight(MW)determination of polymers at quantitative *** this study,we investigate the effect of liquid^(1)H-NMR instrumental setting parameters on the MW determination of polyether diols,namely poly(ethylene glycol)(PEG)and poly(tetramethylene oxide)(PTMO)diols,using hydroxymethylene groups as *** results show that the protons in chain-ends have larger spin-lattice relaxation time(T_(1))than those in main *** let most of the excited protons relax to the equilibrium state,the delay time(d_(1))should be much larger than T_(1)of ***^(13)C decoupling is inactive,the relative errors can be greater than 60%,due to the^(13)C-coupled proton satellite peaks,which can overlap with chain-end groups or be misassigned as *** optimal quantitative NMR conditions for the MW estimation of polyethers are revealed below:standard pulse with inverted gated^(13)C decoupling pulse sequence,32 scans,2.0 s acquisition time in 90 degree of flip angle and 30 s d_(1).The MWs determined from^(1)H quantitative NMR are all smaller than those from SEC which are relative to polystyrene(PS)standards,since the size of polyether chains is larger than that of PS with the same *** addition,the MW obtained from SEC for PTMOs shows larger overestimation than PEGs,suggesting PEG chains are more flexible than PTMO’s.

关键词： End-group analysis Molecular weight NMR Polyether Decoupling

THE THIXOTROPY-LOOP BEHAVIORS OF AN LDPE MELT:EXPERIMENT AND SIMPLE ANALYSIS

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Journal of Hydrodynamics 2006年第6期18卷 666-675页

作者： huang shu-xin LU Chuan-jing Department of Engineering Mechanics Shanghai Jiaotong University Shanghai 200030 China

The time-dependent viscoelastic behaviors of an Low-Density-Pdyethyene（LDPE）（PE-FSB-23D022） melt were experimentally investigated using two types of thixotropy-loop test i.e., the triangular- and the trapezoidal-loop shear test. The shear strengthening was noted in the thixotropy-loop tests not only at high shear rate but also at low shear rate, and it was found that the dimensionless stress amplitude of shear strengthening at low shear rate is larger than that at high shear rate. Moreover, the shear strengthening is a time-dependent viscoelastic behavior that is observed during the initial stage of shearing, and it cannot be found when the time interval corresponding to the increase in shear rate is sufficiently long, The remarkable shear-weakening phenomenon was noticed at higher shear rate when shearing time is prolonged. Five types of the triangular thixotropy-loop results were marked in terms of the configurations of the stress-rate curves, which indicate the complex features of the time-dependent viscoelasticity. A simple model was used to describe the thixotropy-loop tests, and the fitted results showed good agreement with the experimental results.

关键词： thixotropy-loop test time-dependent viscoelasticity LDPE shear strengthening shear weakening

Capture Performance of A Multi-Freedom Wave Energy Converter with Different Power Take-off Systems

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China Ocean Engineering 2019年第3期33卷 288-296页

作者： huang shu-ting SHI Hong-da DONG Xiao-chen College of Engineering Ocean University of China Qingdao 266100 China Shandong Provincial Key Laboratory of Ocean Engineering Qingdao 266100 China

Among the wave energy converters (WECs), oscillating buoy is a promising type for wave energy development in offshore area. Conventional single-freedom oscillating buoy WECs with linear power take-off (PTO) system are less efficient under off-resonance conditions and have a narrow power capture bandwidth. Thus, a multi-freedom WEC with a nonlinear PTO system is proposed. This study examines a multi-freedom WEC with 3 degrees of freedom: surge, heave and pitch. Three different PTO systems (velocity-square, snap through, and constant PTO systems) and a traditional linear PTO system are applied to the WEC. A time-domain model is established using linear potential theory and Cummins equation. The kinematic equation is numerically calculated with the fourth-order Runge–Kutta method. The optimal average output power of the PTO systems in all degrees of freedom are obtained and compared. Other parameters of snap through PTO are also discussed in detail. Results show that according to the power capture performance, the order of the PTO systems from the best to worst is snap through PTO, constant PTO, linear PTO and velocity-square PTO. The resonant frequency of the WEC can be adjusted to the incident wave frequency by choosing specific parameters of the snap through PTO. Adding more DOFs can make the WEC get a better power performance in more wave frequencies. Both the above two methods can raise the WEC’s power capture performance significantly.

关键词： oscillating buoy wave energy converter nonlinear power take-off multi-freedom power capture

Xiaoaiping injection affects the invasionand metastasis of hepatocellular carcinomaby controlling AFP expression

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Oncology and Translational Medicine 2023年第1期9卷 35-42页

作者： shu huang Ganxin Wang Department of Hepatology of Integrated Traditional Chinese and Western Medicine The Third People's Hospital of Hubei Province affiliated with Jianghan UniversityWuhan 430056China Division of Oncology Liyuan HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430077China Cancer Center Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

Objective Xiaoaiping (XAP) is a traditional Chinese medicine that is a commonly used as an anticancerdrug in clinical practice owing to its high efficiency and low toxicity. Specifically, XAP can effectively inhibitthe growth of hepatocellular carcinoma (HCC). Alpha-fetoprotein (AFP) is a key HCC diagnostic marker andis closely related to certain malignant cytological behaviors of HCC. However, whether AFP expression andXAP treatment are related to the invasion and metastasis of HCC remains unclear. In the present study, weaimed to evaluate the effects and underlying mechanism of XAP on the invasion and metastasis of HCC..Methods Using a cell scratch assay, Transwell technology, and western blotting we detected the differentinvasion and metastatic abilities of Hep3B cells in XAP treatment and blank control groups. This allowedcomparison of the invasion and metastatic abilities of Hep3B cells with differing levels of AFP *** mRNA sequencing technology was used to analyze the mechanism of tumor invasion and metastasisassociated with AFP and XAP *** Cell invasion and metastasis abilities in the XAP group were significantly lower than those in thecontrol group (P < 0.05). Additionally, compared to the control group, the expression of AFP significantlydecreased after XAP treatment (P < 0.05). The ability of Hep3B cells to invade and metastasize waspromoted when AFP expression was up-regulated, whereas it was inhibited when AFP was silenced. XAPinjection and AFP regulate the invasion and metastatic ability of HCC by affecting matrix metalloproteinases(MMPs).Conclusion XAP injection inhibits the invasion and metastatic ability of HCC by influencing the expressionof AFP;additionally, this inhibition of AFP is achieved by affecting MMPs.

关键词： Xiaoaiping injection Alpha-fetoprotein(AFP) hepatocellular carcinoma(HCC) invasion,metastasis

SENSITIVE NUMERICAL SIMULATION AND ANALYSIS OF RAINSTORM USING NESTED WRF MODEL

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Journal of Hydrodynamics 2006年第5期18卷 578-586页

作者： WANG shu-chang huang Si-xun LI Yi Institute of Meteorology PLA University of Science and Technology Nanjing 211101 China

Nowadays, the nested grid model is widely used to increase the resolution of numerical model. An attempt to investigate the influence of the newly developed nesting technique of WRF model on the mesoscale numerical simulation of severe storm is described in this article. The results of sensitivity tests infer that the WRF model give more accurate and vivid prediction of severe storm with nesting scheme. As is shown in the tests, simulating value of the precipitation centers using nesting scheme are larger than those without using nesting scheme, which indicates that the simulating precipitation of nested storm is closer to the real rainfall. And there is obvious improvement of distribution of rain area and position of precipitation centers. According to the high resolution output data of the WRF model, deep and detailed analysis of characters of the mesoscale system that triggers the rainstorm is reported in this article, and the thermal and dynamical characters of this Meiyu front severe storm are also discussed.

关键词： WRF nesting numerical simulation mesoscale analysis

Hydrodynamic Response and Power Performance of A Heave and Pitch Buoy Wave Energy Converter Under Bimodal Ochi-Hubble Wave Spectrum

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China Ocean Engineering 2022年第1期36卷 28-37页

作者： huang shu-ting LIU Yan-jun XUE Gang XUE Yi-fan Institute of Marine Science and Technology Shandong UniversityQingdao 266237China School of Mechanical Engineering Shandong UniversityJinan 250061China

In coastal sea areas with the bimodal Ochi-Hubble wave spectrum, such as parts of the China Sea and Indian Ocean,wave energy is the superposition of wind wave and swell. Traditional heaving buoy wave energy converters developed with narrowband wave spectrums suffer from big energy loss in these areas, leading to lower power absorption efficiency and higher generating costs. In contrast, multi-freedom buoy has different resonant frequencies and maximal power capture wave frequencies in different degrees of freedom(DOFs). Therefore, this study proposed using two DOFs to capture the energy of wind wave and swell correspondingly. A heave and pitch buoy model was established by potential flow theory and validated by experimental data. Coupling effect on the motion and power absorption, power capture frequency distribution and power absorption with different linear power takeoff system damping coefficients were analyzed to reveal the hydrodynamic response and the power performance of the two DOFs. The results indicate that by using heave and pitch DOFs, the wave energy components of wind wave and swell were captured in a targeted manner. It demonstrates that the 2-DOF buoy is an effective tool to avoid the energy loss and realize the efficient power absorption in coastal sea areas with bimodal Ochi-Hubble waves.

关键词： wave energy power performance oscillating buoy multi degrees of freedom Ochi−Hubble spectrum

Macrophages-regulating nanomedicines for sepsis therapy

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Chinese Chemical Letters 2023年第3期34卷 100-112页

作者： Jiali Deng Rui Wang shu huang Jinsong Ding Wenhu Zhou Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha 410013China Department of Orthopedics Hunan Provincial People’s HospitalThe First-Affiliated Hospital of Hunan Normal UniversityChangsha 410005China

Sepsis is the leading cause of death in intensive care unit(ICU), which is caused by deregulated immune responses to pathogens infection. Clinically, sepsis treatment is limited to antibiotics and supportive care, while there still lacks of specific molecular therapy. As a type of immune dysfunction disease,macrophages have been recognized as the key immune cells precipitating in the whole process of sepsis,which is activated into M1-like to trigger various inflammatory responses at early stage whereas polarized into M2-like to cause immunosuppression in later stage. Therefore, great attention has been paid on the design of nanomedicines to regulate the functions of macrophages for etiological treatment of sepsis, by virtue of the unique advantages of nano-drug delivery systems, such as enhanced drug bioavailability, targetability, reduced side-effects. This critical review aims to summarize the recent progress of macrophages-regulating nanoparticles for sepsis therapy. First, the essential roles of macrophages in the development and progression of sepsis have been introduced, including the positive roles of macrophages to combat infections and dysfunction of macrophages to cause body damages. We then focus our main attention to discuss the nanomedicines with different therapeutic mechanisms corresponding to each stage of sepsis, such as infection blockage, inflammation inhibition, immune functions recovery, as well as multifunctional nanomedicines. Finally, a few limitations of current nanomedicines are highlighted,and future perspective are speculated for potential clinical translation, which might pave the way for the development of macrophages-centered nanomedicines for more effective sepsis therapy.

关键词： Nanomedicine Sepsis Macrophages Infections Inflammation Immunity