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Isothermal study of effusion cooling flows using a large eddy simulation approach

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航空动力学报 2009年第4期24卷 729-739页

作者： W.P.Bennett J.J.mc Guirk Aeronautical and Automotive Engineering Department Loughborough University

An isothermal numerical study of effusion cooling flow is conducted using a large eddy simulation(LES) *** main types of cooling are considered,namely tangential film cooling and oblique patch effusion *** represent tangential film cooling,a simplified model of a plane turbulent wall jet along a flat plate in quiescent surrounding fluid is *** contrast to a classic turbulent boundary layer flow,the plane turbulent wall jet possesses an outer free shear flow region,an inner near wall region and an interaction region,characterised by substantial levels of turbulent shear stress *** shear stress characteristics hold significant implications for RANS modelling,implications that also apply to more complex tangential film cooling flows with non-zero free stream *** LES technique used in the current study provides a satisfactory overall prediction of the plane turbulent wall jet flow,including the initial transition region,and the characteristic separation of the zero turbulent shear stress and zero shear strain *** effusion patch cooling is modelled using a staggered array of 12 rows of effusion holes,drilled at 30° to the flat plate *** effusion holes connect two channels separated by the flat ***,these comprise of a channel representing the combustion chamber flow and a cooling air supply channel.A difference in pressure between the two channels forces air from the cooling supply side,through the effusion holes,and into the combustion chamber *** from successive effusion rows coalesces to form an aerodynamic film between the combustion chamber main flow and the flat *** practical applications,this film is used to separate the hot combustion gases from the combustion chamber *** numerical model is shown to be capable of accurately predicting the injection,penetration,downstream decay,and coalescence of the effusion *** addition,the numerical model captures entrainmen

关键词： effusion cooling large eddy simulation isothermal analysis film cooling turbulent wall jet

A new viewpoint on the causes of formation of the Great Ice Age

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Chinese Science Bulletin 1997年第14期42卷 1203-1206页

作者： Tang, mc Dong, WJ Lanzhou Institute of Plateau Atmospheric Physics Chinese Academy of Sciences Lanzhou China

THERE have been seven Great Ice Age (GIA) events during the Earth’s evolutionary history of4.6 Ga. Li Siguang put forward an explanation about the causes of their formation andref. [3] summarized various theories concerned. A commonly accepted point is that the even-tual formation of GIA is due to lesser solar radiation absorbed by the Earth. But no one can ex-plain the fact that no GIA had ever appeared from 2.2 to 1.0 Ga B. P. A new viewpoint

关键词： galactic arms geomagnetic polarity galactic and Earth’s magnetic fields coupling Great Ice Age.

Clinical impact of immunomonitoring in the treatment of inflammatory bowel disease

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World Journal of Gastroenterology 2017年第3期23卷 414-425页

作者： Donal Tighe Deirdre mc Namara Department of Gastroenterology Adelaide and Meath Incorporating the National Children’s Hospital TallaghtSchool of Clinical MedicineTrinity College DublinTrinity Academic Gastroenterology Group24 DublinIreland

Despite improvement in outcomes, loss of response(LOR) to tumor necrosis factor-alpha (TNFα) therapies is a big concern in the management of inflammatory bowel disease. LOR is associated with flares of disease, increased hospitalisation rates, need for surgical interventions, and decline in quality of life. LOR may be multifactorial, but immunogenicity makes a significant contribution. Traditionally doses of anti-TNFα have been adjusted based on clinical response, using a standard approach. Immunomonitoring involves the measurement of anti-TNFα trough and antibody levels. It takes into account the underlying pharmacokinetics of anti-TNFα therapies. Expanding on this a treat to target approach may be used, where doses are intensified, or tailored to the individual based on the measurement of anti-TNFα trough and antibody levels. This review looks at the history, evolution, and clinical impact that immunomonitoring is having in the treatment of inflammatory bowel disease. It will focus on the role of immunomonitoring in helping to achieve long lasting deep remission and mucosal healing. It will explore the different options in terms of best measuring trough and antibody levels, explore possible advantages of immunomonitoring, and discuss its role in best optimising response, at induction, during the maintenance phase of treatment, as well as a role in withdrawing or switching therapy.

关键词： Inflammatory bowel disease Ulcerative colitis Immunomonitoring loss of response AntiTNFα trough and antibody levels Crohn’s disease immunogenicity

Microstructure of Al-Si Alloys Rapidly Solidified from the Different Temperature Melts

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Journal of Materials Science & Technology 1999年第3期15卷 225-228页

作者： Gui, mc Jia, J Song, GS Li, QC Beijing Inst Aeronaut Mat Natl Key Lab Adv Composites Beijing 100095 Peoples R China Harbin Inst Technol Harbin 150001 Peoples R China

Hypo- and hyper-eutectic At-Si alloys were rapidly solidified from the tow or high temperature melt using water quenching and melt-spinning technique. The differences in microstructure of rapid solidification alloys were studied by scanning and transmission electron microscopy, and X-ray diffraction methods. The primary silicon in the Al-22(wt pct)Si alloy quenched in room temperature water from high temperature melt was smaller than that quenched from low temperature melt. Compared with the ribbons spun from low temperature melt, the ribbons spun from high temperature melt had finer Al-rich and Si-rich phase particles in either Al-7(wt pct)Si or Al-18(wt pct)Si alloy. The mechanism was explained by the nature of the liquid structure.

关键词： Aluminum alloys

Size Distribution of Ti-Fe Nanoparticles

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Journal of Materials Science & Technology 1997年第4期13卷 318-320页

作者： Ye, F Yang, mc Sun, XK Wei, WD State Key Lab. for RSA Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

Ti-Fe nanoparticles with different concentrations were synthesized by gas condensation method. It is found that the size distribution of single phase nanoparticles obeys log normal distribution, and that of multiple phase nanoparticles is quite different. If it is assumed that the size distribution of each phase in multiple phase nanoparticles obeys log normal distribution as that of single phase particles, the calculated distribution curve is agreeable to the empirical curve. The inferences from the hypothesis are also supported by experimental results.

关键词： Nanotechnology

The neuroprotective potential of endoplasmic reticulum chaperones

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Neural Regeneration Research 2015年第8期10卷 1211-1213页

作者： Todd mc Laughlin Sarah X.Zhang Departments of Ophthalmology and Biochemistry Ross Eye Institute University at Buffalo State University of New York Buffalo NY USA SUNY Eye Institute State University of New York

Diseases of the nervous system are characterized by axon dysfunction,axon degeneration,and neuronal cell *** roster of neurodegenerative diseases is striking in the selective vulnerability of the affected neuronal pop... 详细信息

关键词： endoplasmic reticulum neuronal degeneration manifestation striking populations retina extreme elusive

One-dimensional lazy quantum walks and occupancy rate

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Chinese Physics B 2015年第5期24卷 223-230页

作者：李丹 Michael mc Gettrick 张伟伟张可佳 State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications The De Brun Centre for Computational Algebra School of Mathematics Statistics and Applied Mathematics National University of Ireland

In this paper, we discuss the properties of lazy quantum walks. Our analysis shows that the lazy quantum walks have O（tn） order of the n-th moment of the corresponding probability distribution, which is the same as that for normal quantum walks. The lazy quantum walk with a discrete Fourier transform （DFT） coin operator has a similar probability distribution concentrated interval to that of the normal Hadamard quantum walk. Most importantly, we introduce the concepts of occupancy number and occupancy rate to measure the extent to which the walk has a （relatively） high probability at every position in its range. We conclude that the lazy quantum walks have a higher occupancy rate than other walks such as normal quantum walks, classical walks, and lazy classical walks.

关键词： lazy quantum walk occupancy number occupancy rate

Congenital peritoneal encapsulation: A review and novel classification system

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World Journal of Gastroenterology 2019年第19期25卷 2294-2307页

作者： Aneesh Dave James mc Mahon Assad Zahid Department of Colorectal Surgery Royal Prince Alfred Hospital Sydney Medical School Edward Ford Building the University of Sydney

Congenital peritoneal encapsulation(CPE) is a very rare, congenital condition characterised by the presence of an accessory peritoneal membrane which encases a variable extent of the small bowel. It is unclear how CPE develops,however it is currently understood to be a result of an aberrant adhesion in the peritoneal lining of the physiological hernia in foetal mid-gut development. The condition was first described in 1868, and subsequently there have been only 45 case reports of the phenomenon. No formal, systematised review of CPE has yet been performed, meaning the condition remains poorly understood,underdiagnosed and mismanaged. Diagnosis of CPE remains clinical with important adjuncts provided by imaging and diagnostic laparoscopy. Two thirds of patients present with abdominal pain, likely secondary to sub-acute bowel obstruction. A fixed, asymmetrical distension of the abdomen and differential consistency on abdominal palpation are more specific clinical features present in approximately 10% of cases. CPE is virtually undetectable on plain imaging, and is only detected on 40% of patients with computed tomography scan. Most patients will undergo diagnostic laparotomy to confirm the *** of CPE includes both medical management of the critically-unstable patient and surgical laparotomy, partial peritonectomy and *** following prompt surgical treatment is excellent, with a majority of patients being symptom free at follow up. This review summarises the current literature on the aetiology, diagnosis and treatment of this rare disease. We also introduce a novel classification system for encapsulating bowel diseases, which may distinguish CPE from the commoner, more morbid conditions of abdominal cocoon and encapsulating peritoneal sclerosis.

关键词： Congenital Encapsulation Peritoneum Cocoon Sclerosis

Inhibitory effects of two oligosaccharideson murine melanoma experimental liver metastasis

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World Journal of Gastroenterology 1998年第2期4卷 11-13页

作者： Liu, YP Zhou, RL Wang, YF Cai, mc Beijing Med Univ Dept Cell Biol Beijing 100083 Peoples R China Second Mil Med Univ Dept Biol Shanghai 200433 Peoples R China Beijing Med Univ Dept Organ Chem Beijing 100083 Peoples R China

AIM To observe the effects of a chemically synthesized tetrose and a natural yeast mannan on experimental liver metastasis of mouse melanoma. METHODS After treated with 4mg tetrose (tetrose group) or 4mg mannan (mannan group) for 30 minutes at 37℃, 0 5ml 1×10 6 B16 MBK melanoma cells were injected into the spleen of mice. Fifty five days later, melanoma metastatic nodes on the surface of the liver and in other organs as well as mouse survival time were observed. RESULTS Of the 6 mice in control (B16 cell+PBS) group, 4 died naturally within 55 days, and 2 were killed on the 55th day. All of the 6 mice had metastases in livers, the total number of the melanoma nodes on each liver surface ranged from 2 to 30, with the largest one merging into the whole liver. One mouse had a neoplasm in the remnant site of injection, and 3 had metastases in lungs. In contrast, of the 6 mice in tetrose group, only one died on the 50th day after injection, with 3 metastases in the liver, the largest being 10mm in diameter, the other 5 mice survived until being dissected on the 55th day after injection and had no liver metastasis, but 3 of them had neoplasms in their remnant sites of injection. In mannan group, all of the 6 mice survived and no metastasis was seen except for 2 liver nodes in one mouse with the largest diameter of 1mm. Neither tetrose nor mannan group had metastasis out of the liver, and the weight of liver in the two groups was significantly lower than those in the control group. CONCLUSION Both tetrose and mannan had the effects of preventing melanoma cells from experimental metastasis to and out of the liver, and prolonging the survival time of the mouse.

关键词： liver neoplasms, experimental melanoma oligosaccharides neoplasm metastasis disease models, animal