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Three dimensional shear wave velocity structure of the crust and upper mantle beneath China from ambient noise surface wave tomography

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Earthquake Science 2010年第5期23卷 449-463页

作者： Xinlei Sun Xiaodong Song Sihua Zheng Yingjie Yang Michael h. Ritzwoller Department of Geology University of Illinois at Urbana-Champaign Urbana IL 61801 USA Institute of Earthquake Science China Earthquake Administration Beijing 100036 China CIEI Department of Physics University of Colorado at Boulder Boulder CO 80309 USA

We determine the three-dimensional shear wave velocity structure of the crust and upper mantle in China using Green＇s functions obtained from seismic ambient noise cross-correlation. The data we use are from the China National Seismic Network, global and regional networks and PASSCAL stations in the region. We first acquire cross-correlation seismograms between all possible station pairs. We then measure the Rayleigh wave group and phase dispersion curves using a frequency-time analysis method from 8 s to 60 s. After that, Rayleigh wave group and phase velocity dispersion maps on 1°by 1°spatial grids are obtained at different periods. Finally, we invert these maps for the 3-D shear wave velocity structure of the crust and upper mantle beneath China at each grid node. The inversion results show large-scale structures that correlate well with surface geology. Near the surface, velocities in major basins are anomalously slow, consistent with the thick sediments. East-west contrasts are striking in Moho depth. There is also a fast mid-to-lower crust and mantle lithosphere beneath the major basins surrounding the Tibetan plateau （TP） and Tianshan （Junggar, Tarim, Ordos, and Sichuan）. These strong blocks, therefore, appear to play an important role in confining the deformation of the TP and constraining its geometry to form its current triangular shape. In northwest TP in Qiangtang, slow anomalies extend from the crust to the mantle lithosphere. Meanwhile, widespread, a prominent low-velocity zone is observed in the middle crust beneath most of the central, eastern and southeastern Tibetan plateau, consistent with a weak （and perhaps mobile） middle crust.

关键词： ambient noise surface wave tomography crust and upper mantle China

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An invariant descriptor for conjugate forced convection-conduction cooling of 3D protruding heaters in channel flow

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Frontiers of Mechanical Engineering 2015年第3期10卷 263-276页

作者： Thiago ANTONINI ALVES Paulo h. D. SANTOS Murilo A. BARBUR Department of Mechanical Engineering Federal University ofTechnology Parana Brazil

In this research, the temperatures of three- dimensional （3D） protruding heaters mounted on a conductive substrate in a horizontal rectangular channel with laminar airflow are related to the independent power dissipation in each heater by using a matrix G＋ with invariant coefficients, which are dimensionless. These coefficients are defined in this study as the conjugate influence coefficients （g＋） caused by the forced convec- tion-conduction nature of the heaters＇ cooling process. The temperature increase of each heater in the channel is quantified to clearly identify the contributions attributed to the self-heating and power dissipation in the other heaters （both upstream and downstream）. The conjugate coefficients are invariant with the heat generation rate in the array of heaters when assuming a defined geometry, invariable fluid and flow rate, and constant substrate and heater conductivities. The results are numerically obtained by considering three 3D protruding heaters on a twodimensional （2D） array by ANSYS/FluentTM 15.0 software. The conservation equations are solved by a coupled procedure within a single calculation domain comprising of solid and fluid regions and by considering a steady state laminar airflow with constant properties. Some examples are shown, indicating the effects of substrate thermal conductivity and Reynolds number on conjugate influence coefficients.

关键词： channel flow conjugate forced convection-conduction cooling conjugate influence coefficients dis-crete heating invariant descriptor thermal management

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An Improved Method for Preparation of Uniform and Functional Mitochondria from Fresh Liver

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Journal of Clinical and Translational hepatology 2019年第1期7卷 46-50页

作者： Nagham Khouri Farah Xiaocong Liu Catherine h.Wu George Y.Wu Department of Medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterFarmingtonCTUSA

Background and Aims:As the major energy source for mammalian cells,mitochondria have been the subject of numerous ***,the isolation and purification of healthy mitochondria,especially from fresh tissue,remains *** most popular methods and kits involve various centrifugation steps which require substantial time and equipment but do not consistently provide pure preparations of functional *** aim of this study was to determine whether methods could be devised to improve the purity and yield of functional mitochondria from fresh ***:Fresh mouse liver was homogenized,and cells *** size analysis,quantitation of mitochondrial DNA,mitochondrial oxygen consumption,and purity of mitochondria(by electron microscopy)were measured in samples after various purification steps and significant differences ***:A two-step procedure consisting of centrifugation followed by filtration through 1.2μand 0.8μfilters resulted in uniform mitochondrial preparations with diameters between 520-540 nm,and approximately 5-times more pure *** mitochondria thus obtained had oxygen consumption and sensitivities to mitochondrial inhibitors that were indistinguishable from those purified by centrifugation *** microscopy confirmed the presence of more uniform and 4-5 times greater concentrations of mitochondria compared to centrifugation ***:A two-step procedure consisting of sequential centrifugation followed by filtration is a rapid method for the production of highly purified,uniform and functional mitochondria.

关键词： Mitochondria Isolation Filtration Purified Uniform Functional

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Conduit necrosis following esophagectomy: An up-to-date literature review

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World Journal of Gastrointestinal Surgery 2019年第3期11卷 155-168页

作者： Antonios Athanasiou Mairead hennessy Eleftherios Spartalis Benjamin h L Tan Ewen A Griffiths Department of Upper GI Bariatric and Minimally Invasive Surgery St.James' University Hospital Leeds Teaching Hospitals NHS Trust Department of Anaesthesia University Hospital of Waterford Laboratory of Experimental Surgery and Surgical Research University of Athens Medical School Department of Upper Gastrointestinal Surgery University Hospitals Birmingham NHS Foundation Trust

Esophageal conduit ischaemia and necrosis is an uncommon but devastating complication of esophagectomy and remains one of the most challenging issues in surgical practice. The incidence, time interval to develop symptoms, and clinical presentation are highly variable with no predictable pattern. Evidence comes from case reports and case series rather than randomized controlled *** describe the issues surrounding conduit necrosis affecting the stomach,jejunum and colon as an esophageal replacement and the advantages,disadvantages and challenges of each type of reconstruction. Diagnosis is challenging for the most experienced surgeon. Upper gastrointestinal endoscopy and computed tomography thorax with both oral and intravenous contrast is the gold standard. Management, either conservative or interventional is also a difficult decision. Management options include conservative treatment and more aggressive treatments such as stent insertion, surgical debridement and repair of the esophagus using jejunum, colon or a musculocutaneous flap. In spite of recent advances in surgical techniques, there is no reliable strategy to manage esophageal conduit necrosis. Our review covers the pathophysiology and clinical significance of esophageal necrosis while highlighting current techniques of prevention, diagnosis and treatment of this life-threatening condition.

关键词： Esophagectomy Esophageal cancers Esophagogastric anastomosis

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Effect of Conductive Fillers on the Cyclic Stress-Strain and Nano-Scale Free Volume Properties of Silicone Rubber

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Chinese Journal of Polymer Science 2014年第5期32卷 558-567页

作者： M.h.Abd-El Salam S.El-Gamal M.Mohsen D.M.Abd El-Maqsoud Physics Department Faculty of Education Ain Shams University Physics Department Faculty of Science Ain Shams University

The effect of carbon black （CB） and graphite （G） powders on the macroscopic and nano-scale free volume properties of silicone rubber based on poly（di-methylsiloxane）（PDMS） was studied through thermal and cyclic mechanical measurements, as well as with positron annihilation lifetime spectroscopy （PALS）. The melting temperature of the composites （Tm） and the endothermic enthalpy of melting （Δhm） were estimated by differential scanning calorimetry （DSC）. Tm and the degree of crystallinity （χc） of PDMS composites were found to decrease with increasing the CB content. This can be explained due to the increase in physical cross-linking which results in a decrease in the crystallite thickness. Besides, χc was found to be dependent on the filler type. Cyclic stress-strain behavior of PDMS loaded with different contents of filler has been studied. Mullins ratio （RM） was found to be dependent on the filler type and content. It was found that, RM increases with increasing the filler content due to the increase in physical cross-linking which results in a decrease in the size of free volume, as observed through a decrease of the o-Ps lifetime τ3 measured by PALS. Moreover, the hysteresis in PDMS-CB composites was more pronounced than in PDMS-G composites. Furthermore, a correlation was established between the free volume Vf and the mechanical properties of PDMS composites containing different fillers. A negative correlation was observed between Vf and RM.

关键词： Positron annihilation Positronium Free volume Si-rubber Composite Cyclic mechanical properties.

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Internal Flow Simulation of high-Performance Solid Rockets using a k-ω Turbulence Model

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Journal of Thermal Science 2005年第2期14卷 114-119页

作者： V.R.SANAL KUMAR h.D.KIM B.N.RAGhUNANDAN T.SETOGUChI S.RAGhUNAThAN Andong National University Andong 760-749 KoreaAndong National University Andong 760-749KoreaIndian Institute of Science Bangalore-560 012IndiaSaga University Honjo-machiSaga 840-8502JapanThe Oueen's University of Belfast Northern IrelandUK

For technological reasons many high-performance solid rocket motors are made from segmented propellant grains with non-uniform port geometry. In this paper parametric studies have been carried out to examine the geometric dependence of transient flow features in solid rockets with non-uniform ports. Numerical computations have been carried out in an inert simulator of solid propellant rocket motor with the aid of a standard k-ω turbulence model. It was seen that the damping of the temperature fluctuation is faster in solid rocket with convergent port than with divergent port geometry. We inferred that the damping of the flow fluctuations using the port geometry is a meaningful objective for the suppression and control of the instability and/or pressure/thrust oscillations during the starting transient of solid rockets.

关键词： solid rockets pressure spike instability thrust oscillation turbulent separation.

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Resource assessment of copper deposits in China

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Journal of Central South University of Technology 2005年第z1期12卷 108-113页

作者： ZhANG Qin-li GU De-sheng T. Shoji h. Kaneda School of Resources and Safety Engineering Central South University Changsha 410083 China School of Resources and Safety Engineering Central South University Changsha 410083 China Department of Environment System School of Frontier Sciences the University of Tokyo Tokyo 113-8656 Japan Department of Life Area Environmental Science Faculty of Science the Toho University Tiba 274-8510 Japan

Copper-bearing deposits of China are statistically analyzed in terms of ore grade, metal amount and ore tonnage. Each of grade and metal amount shows more or less a lognormal distribution. Analysis gives 10 copper metallogenic districts, each having specific densities of deposit numbers and copper reserves larger than 3. Based on the ratio of copper in ore value (Rcu), Chinese copper deposits are classified into two groups: mainly copper-producing deposits (MC: Rcu≥0.5) and accessorily copper-producing deposits (AC: Rcu＜0. 5). The grade-tonnage relation of MC deposits can be combined by two exponential functions approximating high grade (＞ 3.0 %) and low grade (＜2.0%) parts. The critical copper grade, which is obtained from the low grade part of the relation, is 0. 34 %. Chinese copper resources are concluded to become pessimistic, because some mines are working with grades close to this critical value. Taking account of the fact that many copper deposits are actually polymetallic, Cu-equivalent grades, which are converted from ratios of metal prices to the copper price, are also introduced. The critical Cu-equivalent grade of MC deposits (0. 43 % ) also suggests that Chinese copper resources are pessimistic.

关键词： copper resources critical grade assessment

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中国大陆科学钻探主孔中磷灰石的磁黄铁矿出溶结构

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岩石学报 2007年第12期23卷 3249-3254页

作者：朱永峰 h．-J．Massonne 北京大学地球与空间科学学院造山带与地壳演化教育部重点实验室 Institut für Mineralogie und Kristallchemie Universitt StuttgartAzenbergstr.18D-70174 StuttgartGermany

在中国大陆科学钻探主孔中部的榴辉岩样品B1021R642P40a、B1039R646P47a、B1046R648P4c和B1053R649P74k中,我们发现了磷灰石的磁黄铁矿出溶结构。磷灰石是该榴辉岩的主要副矿物,其自形程度较高,与石榴石共生。样品中几乎所有磷灰石均发... 详细信息

在中国大陆科学钻探主孔中部的榴辉岩样品B1021R642P40a、B1039R646P47a、B1046R648P4c和B1053R649P74k中,我们发现了磷灰石的磁黄铁矿出溶结构。磷灰石是该榴辉岩的主要副矿物,其自形程度较高,与石榴石共生。样品中几乎所有磷灰石均发育出溶结构,至少存在两组相互垂直的出溶棒。出溶棒形状规则,一样宽(h、F、Cl和S,它的深循环因此可能对地球的水、硫以及其它挥发性组分的全球平衡具有重要影响。

关键词：中国大陆科学钻探苏鲁超高压地体榴辉岩磷灰石出溶结构磁黄铁矿

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Indole and Its Derivatives as Corrosion Inhibitors for C-Steel during Pickling

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Journal of Materials Science & Technology 2000年第3期16卷 291-296页

作者： S.h.Sanad, A.A.Ismail and A.A.El-Meligi (Physical Chemistry Dept., National Research Centre, Dokki, Cairo, Egypt) Physical Chemistry Dept. National Research Centre Dokki Cairo Egypt

The corrosion of three types of C-steel in 10% hydrochloric acid solution has been investigated in the absence and the presence of the inhibitors, indole (A), indole acetic acid (B), indole butyric acid (C), and 3-acetyl indole (D), by weight-loss measurements at different temperatures (30～70℃). The results showed that inhibiting efficiency depended upon the presence of the substituted groups in the pyrrole ring. The inhibiting efficiency of the inhibitors increased in the order: Inh. Ch. Bh. Ah. D. Linear Arrhenius plots were obtained in the absence and the presence of inhibitors. Results elucidated the effect of temperatures and molecular structure on the inhibition efficiency. The activation energy, Ea, of the three alloys was calculated and it was found that it depended on the type of steel and inhibitor.

关键词： Carbon steel

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Facial basal cell carcinoma:A retrospective study of 67 cases

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World Journal of Clinical Cases 2023年第7期11卷 1488-1497页

作者： Afrah A Khalil hamid h Enezei Tahrir N Aldelaimi Raid M Al-Ani Department of Oral Diagnosis College of DentistryUniversity of AnbarRamadi 31001AnbarIraq Department of Oral and Maxillofacial Surgery College of DentistryUniversity of AnbarRamadi 31001AnbarIraq Department of Surgery/Otolaryngology University of AnbarCollege of MedicineRamadi 31001AnbarIraq

BACKGROUND Basal cell carcinoma(BCC)is a slow-growing malignant tumor characterized by local invasiveness but an exceptionally rare metastatic *** ideally affects sun-exposed skin of older patients with more propensity for the facial *** To evaluate the different clinicopathological characteristics of the facial BCC and the efficacy and safety of diode laser for the treatment of these *** We retrospectively reviewed facial BCC lesions ofhem to diode laser ablation during the period from September 2016 to August 2021 at Al-Ramadi Teaching hospital,Ramadi City,*** matching the age,gender,duration,site,and clinical and histological types were registered for every *** functional and aesthetic outcomes and complications following diode laser ablation for each patient were also *** Of 67 patients with facial BCC,there was 65.67%from the age group≥60 years and 58.21%*** mean duration of the lesions was 5.15±1.836 *** most involved location was the nose(29.85%).About half of the cases belong to the noduloulcerative *** histological type comprises 40.3%of the cases,while the least was keratotic(13.4%).Moreover,65.2%of the solid cases were from the age group≤60 years and 38.6%of the adenoid type from the age group>60 years(P value=0.007).Excellent aesthetic and functional outcomes were reported in all cases after 6 mo of *** complications were reported after diode laser *** Facial BCC was mostly seen in the elderly and *** mean duration was 5.15 *** nose was the commonest involved *** lesions were seen in approximately half of the *** age of the patients determined the histological type of the lesion(solid type was mostly seen in the age group≤60 years,while,adenoid in the age group>60 years).Diode laser ablation showed excellent functional and aesthetic outcomes following a 6-mo follow-up.

关键词： Basal cell carcinoma Maxillofacial pathology histopathology Malignant skin tumors Dermatological lesions Diode laser

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