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The properties of Sn-Zn-Al-La fusible alloy for mitigation devices of solid propellant rocket motors

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Defence Technology（防务技术） 2022年第9期18卷 1688-1696页

作者： Zi-ting Wei Nan Li Jian-xin Nie Jia-hao Liang Xue-yong Guo Shi Yan Tao Zhang qing-jie Jiao State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

The Al and La elements are added to the Sn9Zn alloy to obtain the fusible alloy for the mitigation devices of solid propellant rocket motors. Differential scanning calorimetry(DSC), metallographic analysis,scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS), tensile testing and fracture analysis were used to study the effect of Al and La elements on the microstructure, melting characteristics, and mechanical properties of the Sn9Zn alloy. Whether the fusible diaphragm can effectively relieve pressure was investigated by the hydrostatic pressure at high-temperature test. Experimental results show that the melting point of the Sn9Zn-0.8Al0·2La and Sn9Zn-3Al0·2La fusible alloys can meet the predetermined working temperature of ventilation. The mechanical properties of those are more than 35% higher than that of the Sn9Zn alloy at-50°C-70°C, and the mechanical strength is reduced by 80% at 175°C. It is proven by the hydrostatic pressure at high-temperature test that the fusible diaphragm can relieve pressure effectively and can be used for the design of the mitigation devices of solid propellant rocket motors.

关键词： Mitigation devices Solid propellant rocket motors Sn9Zn Al element La element Hydrostatic pressure at high-temperature test

Thyroid dysfunction, either hyper or hypothyroidism, promotes gallstone formation by different mechanisms

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2016年第7期17卷 515-525页

作者： Yong WANG Xing YU Qun-zi ZHAO Shu ZHENG Wen-jie qing Chun-di MIAO Jaiswal SANJAY Department of Thyroid Surgery the Second Affiliated Hospital School of Medicine Zhejiang University Cancer Institute the Second Affiliated Hospital School of Medicine Zhejiang University Department of Clinical Medicine School of Medicine Zhejiang University

We have investigated comprehensively the effects of thyroid function on gallstone formation in a mouse model. Gonadectomized gallstone-susceptible male C57BL/6 mice were randomly distributed into three groups each of which received an intervention to induce hyperthyroidism, hypothyroidism, or euthyroidism. After 5 weeks of feeding a lithogenic diet of 15% （w/w） butter fat, 1% （w/w） cholesterol, and 0.5% （w/w） cholic acid, mice were killed for further experiments. The incidence of cholesterol monohydrate crystal formation was 100% in mice with hyperthyroidism, 83% in hypothyroidism, and 33% in euthyroidism, the differences being statistically significant. Among the hepatic lithogenic genes, Tr~ was found to be up-regulated and Rxr down-regulated in the mice with hypothyroidism. In contrast, Lxra, Rxr, and Cyp7al were up-regulated and Fxr down-regulated in the mice with hyperthyroidism. In conclusion, thyroid dysfunction, either hyperthyroidism or hypothyroidism, promotes the formation of cholesterol gallstones in C57BL/6 mice. Gene expression differences suggest that thyroid hormone disturbance leads to gallstone formation in different ways. Hyperthyroidism induces cholesterol gallstone formation by regulating expression of the hepatic nuclear receptor genes such as Lxra and Rxr, which are significant in cholesterol metabolism pathways. However, hypothyroidism induces cholesterol gallstone formation by promoting cholesterol biosynthesis.

关键词： Hypothyroidism Hyperthyroidism Cholesterol gallstone C57BW6 mice Hepatic lithogenic genes

Porous Alumina Ceramics Fabricated by Spark Plasma Sintering

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Chinese Journal of Aeronautics 2006年第B12期19卷 257-260页

作者： WANG Kun FU Zheng-yi PENG Yong WANG Yu-cheng ZHANG Jin-yong ZHANG qing-jie State Key Lab of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China

Porous alumina of regular spherical particles was fabricated with the spark plasma sintering （SPS） and then compared to those obtained through conventional hot pressing （HP）. The effects of the parameters of the heating process on porosity were also investigated, Microstructural studies suggest that porous ingots including regular pores be made out of regular spherical alumina particles due to the close sphere packages. A comparative study on the relative necks of the specimens produced by SPS and HP indicates an enhancement of neck growth with SPS. Contrasting the theoretical values to the experimental results over the relative necks indicates that a proper relationship between the relative necks and the porosity can be established by a sintering model.

关键词： spark plasma sintering (SPS) porous alumina ceramics sintering neck

Nicotinamide mononucleotide adenylyltransferase 1 gene NMNAT1 regulates neuronal dendrite and axon morphogenesis in vitro

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Chinese Medical Journal 2011年第20期124卷 3373-3377页

作者： ZHAO Hong ZHANG Jing-yu YANG Zi-chao LIU Ming GANG Bao-zhi ZHAO qing-jie Department of Neurology the First Affiliated Hospital of Harbin Medical University Harbin Heilongjiang 150001 China Department of Neurology the Fourth Affiliated Hospital of Harbin Medical University Harbin Heilongjiang 150001 China Department of Oncology the Fourth Affiliated Hospital of Harbin Medical University Harbin Heilongjiang 150001 China

Background Wallerian degeneration is a self-destructive process of axonal degeneration that occurs after an axonal injury or during neurodegenerative disorders such as Parkinson＇s or Alzheimer＇s disease. Recent studies have found that the activity of the nicotinamide adenine dinucleotide （NAD） synthase enzyme, nicotinamide mononucleotide adenylyltransferase 1 （NMNAT1） can affect the rate of Wallerian degeneration in mice and drosophila. NMNAT1 protects neurons and axons from degeneration. However, the role of NMNAT1 in neurons of central nervous system is still not well understood. Methods We set up the culture of primary mouse neurons in vitro and manipulated the expression level of NMNAT1 by RNA interference and gene overexpression methods. Using electroporation transfection we can up-regulate or down-regulate NMNAT1 in cultured mouse dendrites and axons and study the neuronal morphogenesis by immunocytochemistry. In all functional assays, FK-866 （CAS 658084-64-1）, a highly specific non-competitive inhibitor of nicotinamide phosphoribosyltransferase was used as a pharmacological and positive control. Results Our results showed that knocking down NMNAT1 by RNA interference led to a marked decrease in dendrite outgrowth and branching and a significant decrease in axon growth and branching in developing cortical neurons in vitro. Conclusions These findings reveal a novel role for NMNAT1 in the morphogenesis of developing cortical neurons, which indicate that the loss of function of NMNAT1 may contribute to different neurodegenerative disorders in central nervous system.

关键词： nicotinamide-nucleotide adenylyltransferase neurogenesis RNA interference gene expression

DNA Damage-driven Inflammatory Cytokines:Reprogramming of Tumor Immune Microenvironment and Application of Oncotherapy

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Current Medical Science 2024年第2期44卷 261-272页

作者： Meng-jie WANG Yu XIA qing-lei GAO Department of Obstetrics and Gynecology National Clinical Research Center for Obstetrics and GynecologyTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Key Laboratory of Cancer Invasion and Metastasis(Ministry of Education) Hubei Key Laboratory of Tumor Invasion and MetastasisTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

DNA damage occurs across tumorigenesis and tumor *** intrinsic DNA damage can not only increase the risk of mutations responsible for tumor generation but also initiate a cellular stress response to orchestrate the tumor immune microenvironment(TIME)and dominate tumor *** evidence documents that multiple signaling pathways,including cyclic GMP-AMP synthase-stimulator of interferon genes(cGAS-STING)and ataxia telangiectasia-mutated protein/ataxia telangiectasia and Rad3-related protein(ATM/ATR),are activated downstream of DNA damage and they are associated with the secretion of diverse *** cytokines possess multifaced functions in the anti-tumor immune ***,it is necessary to deeply interpret the complex TIME reshaped by damaged DNA and tumor-derived cytokines,critical for the development of effective tumor *** manuscript comprehensively reviews the relationship between the DNA damage response and related cytokines in tumors and depicts the dual immunoregulatory roles of these *** also summarize clinical trials targeting signaling pathways and cytokines associated with DNA damage and provide future perspectives on emerging technologies.

关键词： DNA damage tumor immune microenvironment inflammatory cytokines cancer therapy

Expression of ICAM-1, HLA-DR, and CD80 on peripheral circulating CD_1αDCs induced in vivo by IFN-αin patients with chronic hepatitis B

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World Journal of Gastroenterology 2006年第9期12卷 1447-1451页

作者： Yong-Sheng Yu Zheng-Hao Tang Jing-Chao Han Min Xi jie Feng Guo-qing Zang Department of Infectious Diseases Sixth People's Hospital of Shanghai Jiaotong University Shanghai 200233 China

AIM: To explore the effects of interferon-α(IFN-α) application on peripheral circulating CD1αdendritic cells (DCs) in patients with chronic hepatitis B, and the expression of HLA-DR, CD80, and ICAM-1 on CD1αDCs in order to explore the mechanism of immune modulation of IFN-α. METHODS: By flow cytometry technique, changes of CD1αDCs were monitored in 22 patients with chronic hepatitis B treated with IFN-αand in 16 such patients not treated with IFN-αwithin three months. Meanwhile, the expression of HLA-DR, CD80, and ICAM-1 on CD1αDCs was detected. RESULTS: In the group of IFN-αtreatment, the percentage of CD1αDCs in peripheral blood mono-nuclear cells was increased after three months of therapy. In patients who became negative for HBV-DNA after IFN-αtreatment, the increase of DCs was more prominent, while in control, these changes were not observed. Increased expression of HLA-DR, CD80, and ICAM-1 on CD1αDCs was also observed. CONCLUSION: CD1αDCs can be induced by IFN-αin vivo, and the immune related molecules such as HLA-DR, CD80, and ICAM-1 are up-regulated to some degree. This might be an important immune related mechanism of IFN-αtreatment for chronic hepatitis B.

关键词： Chronic hepatitis B DC Immune costimulatory molecules Immunotherapy IFN-α

THE LIMITING CASE OF THIELE'S INTERPOLATING CONTINUED FRACTION EXPANSION

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Journal of Computational Mathematics 2001年第4期19卷 433-444页

作者： jie-qing Tan (Institute of Applied Mathematics, College of Science and CAD/CG Division College of Computer & Information Hefei, University of Technology, Hefei 230009, China) 中国科学技术大学安徽合肥 230009

By means of the determinantal formulae for inverse and reciprocal differences with coincident data points, the limiting case of Thiele's interpolating continued fraction expansion is studied in this paper and given numerical example shows that the limiting Thiele's continued fraction expansion can be determined once for all instead of carrying out computations for each step to obtain each convergent as done in [3].

关键词： Continued fraction Inverse difference Reciprocal difference Expansion.

Numerical simulations of viscous flow around the obliquely towed KVLCC2M model in deep and shallow water

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Journal of Hydrodynamics 2016年第3期28卷 506-518页

作者：孟庆杰万德成 State Key Laboratory of Ocean Engineering School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong University Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration

By solving the unsteady Reynolds averaged Navier-Stokes （RANS） equations in combination with the k- ε SST turbulence model, the unsteady viscous flow around the obliquely towed tanker KVLCC2M model in both deep and shallow waters is simulated and the hydrodynamic forces, the surface pressure distribution, and the wake field are calculated. The overset grid technology is used to avoid the grid distortion in large drift angle cases. The effects of the free surface are taken into account. At the first stage, the deep water cases with five oblique angles are designed as the benchmark test cases. The predicted wake field, the surface pressure distribution and the hydrodynamic forces acting on the hull agree well with the corresponding experimental data, implying the capability of the present method in the prediction of the viscous flow around the tanker drifting in shallow water. A set of systematic computations with varying water depths and drift angles are then carried out to study the viscous flow around the model drifting in shallow water. The forces and moments, as well as the surface pressure distribution are predicted and analyzed. The most significant changes such as the increased stagnation pressure in the bow, the acceleration of the flow along the ship＇s sides and in the gap between ship and seabed, the lower hull pressure and finally, the stronger vortices along the bilges and weaker vortices with larger diameters in the wake are noticed.

关键词： drift motionm shallow water viscous flow hydrodynamic forces manoeuvability

Seed Zone Properties and Crop Performance as Affected by Three No-Till Seeders for Permanent Raised Beds in Arid Northwest China

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Journal of Integrative Agriculture 2012年第10期11卷 1654-1664页

作者： HE Jin LI Hong-wen Allen David McHugh WANG qing-jie LI Hui Rabi Gautam Rasaily Khokan Kumer Sarker Beijing Key Laboratory of Optimized Design for Modern Agricultural Equipment/College of Engineering China Agricultural University National Center for Engineering in Agriculture University of Southern Queensland

The no-till seeders of various soil opener configurations have been shown to produce various soil physical responses in relation to soil and climate conditions, thus affecting crop performance in permanent raised beds （PRB） systems. This is particularly important in arid Northwest China where large volumes of residue are retained on the soil surface after harvest. In Zhangye, Gansu Province, China, a field trial assessed the effects of three typical （powered-chopper, powered-cutter and powered-disc） PRB no-till seeders and one traditional seeder on soil disturbance, residue cover index, bulk density, fuel consumption, plant growth, and subsequent yield. In general, seedbed conditions and crop performance for PRB no- till seeders seeded plots were better than for traditional seeded plots. In PRB cropping system, the powered-chopper seeder decreased mean soil disturbance and increased residue cover index compared to powered-disc and -cutter seeders. However, the results indicated that soil bulk density was 2.3-4.8% higher, soil temperature was 0.2-0.6℃ lower, and spring wheat emergence was 3.2-4.7% less. This was attributed to greater levels of residue cover and firmer seedbeds. Spring maize and wheat performance in the powered-cutter and -disc treatments was better （non-significant） than powered- chopper treatment. So powered disc no-till seeder, which generally provided the best planting condition and the highest yield, appeared to be the suitable seeder in heavy residue cover conditions. Considering the precision requirements for soil disturbance and residue cover, the powered strip-chopping no-till seeder could be a suitable option for PRB cropping system in Northwest China. Although these results are preliminary, they are still valuable for the design and selection of no-till seeders for PRB cropping systems in arid Northwest China.

关键词： no-till seeder permanent raised beds crop growth seedbed yield