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Growth of a Cellular/dendritic Array

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Journal of Materials Science & Technology 1997年第3期13卷 161-172页

作者： J.d.Hunt Q.Hant and X.Wan(dept. of Materials, university of Oxford, Parks Road, Oxford OX1 3PH, u.K.) dept. of Materials University of Oxford Parks Road Oxford OX1 3PH United Kingdom

This paper describes a time dependent numerical model for the steady and non-steady growthof a cellular/dendritic array in a moving linear temperature field. The model gives fully selfconsistent solutions for axisymmetric interface shapes, predicts cellular and dendritic spacings,undercoolings and the transition between structures. An important feature of the model is thatthe spacing selection mechanism has been treated. The model predicts two different dendriticgrowth regions. One occurs at low dimensionless velocities where the dendrite array is uniform:a small stable range of spacings is predicted and the prediction agrees very well with existing experiments. The other occurs at high dimensionless velocities where the dendrite array is irregular, its minimum spacing is inversely proportional to velocity Experiment was carried out to verify the prediction. The irregular dendrite array was observed and the measured minimum spacing fitted extremely well with the prediction. By fitting the numerical results. Relatively simple analytic expressions are obtained which provide an insight into the cellular and dendritic growth processes and are useful for comparing theory with experiment.

关键词： Figure Rev Growth of a Cellular/dendritic Array

Studies on impact sensitivity of nanosized trinitrotoluene (TNT) confined in silica processed by sol-gel method

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defence Technology（防务技术） 2016年第1期12卷 46-51页

作者： s.v.ingale p.b.wagh p.u.sastry c.b.basak d.bandyopadhyay s.b.phapale satish c.gupta Applied Physics division Bhabha Atomic Research Centre Mumbai India Solid State Physics division Bhabha Atomic Research Centre Mumbai India Glass andAdvanced Materials division Bhabha Atomic Research Centre Mumbai India Heavy Water division Bhabha Atomic Research Centre Mumbai India Chemistry division Bhabha Atomic Research Centre Mumbai India

Nano-sized trinitrotoluene(TNT) material restrained in silica gel has been prepared by using the sol-gel process to study the effect of varying porosity in gel on the sensitivity of TNT. The TNT content in the gel has been varied from 60 to 90 wt %(at fixed acetone/tetramethoxysilane ratio of 50). Also, for a fixed TNT content of 75 wt %, the pore structure in the gel has been varied by changing the ratio of silica gel precursor to the solvent. The resultant TNT–silica gel composites have been characterized using scanning electron microscopy, thermal analysis, small angle X-ray scattering and surface area analysis techniques. Impact sensitivity studies were carried out using Fall Hammer Impact Test. The results showed that the sensitivity of nanostructured explosives prepared by sol-gel process can be tailored precisely by controlling the process parameters.

关键词：溶胶-凝胶法三硝基甲苯 TNT 敏感性二氧化硅纳米溶胶-凝胶过程扫描电子显微镜

Geoelectrical survey over perched aquifers in the northern part of upper Sakarya River Basin,Türkiye

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Journal of Groundwater Science and Engineering 2022年第4期10卷 335-352页

作者： Can Ertekin Emin u ulugergerli Aegean Regional directorate of Mineral Research and Exploration İzmirTürkiye Çanakkale Onsekiz Mart university Department of Geological EngineeringTerzioğlu CampusÇanakkaleTürkiye Çanakkale Onsekiz Mart university Engineering FacultyDepartment of Geophysical EngineeringTerzioğlu CampusÇanakkaleTürkiye

In this study,a groundwater exploration survey was conducted using the dC Resistivity(dCR)method in a hydrogeological setting containing a perched *** data were gathered and an electrical tomography section was recovered using conventional four-electrode instruments with a Schlumberger array and a two-dimensional(2d)inversion *** proposed scheme was tested over a synthetic threedimensional(3d)subsurface model before deploying it in a field *** proposed method indicated that gathering data with simple four-electrode instruments at stations along a line and 2d inversion of datasets at multiple stations can recover depth intervals of the studied aquifer in the hydrogeological setting even if it has a 3d *** this study,2d inversion of parallel profiles formed a pseudo-3d volume of the subsurface resistivity structures and mapped out multiple resistive(>25 ohm·m)bodies at shallow(between 50-100 m)and deep sections(>150 m).In general,the proposed method is convenient to encounter geological units that have limited vertical and spatial extensions in any direction and presents resistivity contrast from groundwater-bearing geologic materials.

关键词： Groundwater Perched Aquifer dC Resistivity Inversion Sakarya River Türkiye

Evaluation of anti-metastatic effect of chitosan nanoparticles on esophageal cancer-associated fibroblasts

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Journal of Cancer Metastasis and Treatment 2016年第1期2卷 259-267页

作者： Pravin d.Potdar Aashutosh u.Shetti department of Molecular Medicine and Biology Jaslok Hospital and Research CentreMumbai 400026India

Aim:Esophageal cancer is one of the major types of cancers,causing death of approximately 5%of all cancer *** is due,in large part,to both relatively ineffectual and unavailable *** order to develop an effective treatment strategy against esophageal cancer,it is important to target metastatic *** the present study,we have used a cancer-associated fibroblast(CAF)cell line derived from culturing peripheral blood mononuclear cells from a metastatic esophageal cancer patient to see whether chitosan nanoparticles(Ch-Np)treatment can modulate the metastatic phenotype of CAF cells by using various cellular and molecular ***:A CAF cell line was developed from peripheral blood mononuclear cells(PBMC)from a metastatic esophageal cancer *** cells were treated with 100μg/mL of chitosan nanoparticle in vitro for the morphological and oncogenic characteristic studies,along with the expression of various genes involved in process of tumor development and *** such as Light and Phase Contrast Microscopy,cell growth rate,Scratch metastatic assay,and molecular profiling were carried out to see changes in CAF cells before and after Ch-Np ***:It was observed that CAF cells grew in monolayer and had a doubling time of 25±0.38 ***,the cells had a fibroblastic *** treatment with 100μg/mL of Ch-Np in vitro,there was an increased doubling time to 30±0.83 ***,Scratch Assay showed an inhibition in the metastatic property of these *** findings were confirmed with gene expression *** was also observed that there was complete down-regulation of metastatic genes MMP1 and MMP9 and chemokines such as CXCR-4,CXCR-7,CCR-5,and SdF-1,indicating that Ch-Np inhibited the metastatic characteristic of CAF ***:This study has shown that there was an inhibition of metastatic properties of CAF cells after treatment with Ch-Np,suggesting that Ch-Np can be a delivery system used

关键词： Cancer-associated fibroblast molecular markers metastasis chitosan nanoparticle anti-metastatic metastatic genes

Cross-sectional warping and precision of the first-order shear deformation theory for vibrations of transversely functionally graded curved beams

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Applied Mathematics and Mechanics(English Edition) 2023年第12期44卷 2109-2138页

作者： u.N.ARIBAS M.AYdIN M.ATALAY M.H.OMuRTAG department of Civil Engineering Istanbul Medipol UniversityIstanbul 34810Türkiye

The warping may become an important factor for the precise transverse vibrations of curved ***,the first aim of this study is to specify the structural design parameters where the influence of cross-sectional warping becomes great and the first-order shear deformation theory lacks the precision *** outof-plane vibrations of the first-order shear deformation theory are compared with the warping-included vibrations as the curvature and/or thickness increase for symmetric and asymmetric transversely-functionally graded(TFG)curved *** second aim is to determine the influence of design parameters on the *** circular/exact elliptical beams are formed via curved mixed finite elements(MFEs)based on the exact curvature and *** stress-free conditions are satisfied on three-dimensional(3d)constitutive *** variation of functionally graded(FG)material constituents is considered based on the power-law *** cross-sectional warping deformations are defined over a displacement-type FE *** warping-included MFEs(W-MFEs)provide satisfactory 3d structural characteristics with smaller degrees of freedom(dOFs)compared with the brick *** Newmark method is used for the forced vibrations.

关键词： mixed finite element(MFE) free vibration forced vibration warping exact elliptical beam functionally graded(FG)beam

diurnal changes in bacterial communities in oxic surface and hypoxic middle seawater layers of the Changjiang River Estuary

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Acta Oceanologica Sinica 2021年第4期40卷 92-106页

作者： Yan Huang Lei Yuan Yingping Fan Habib u Rehman Jakhrani Jianxin Wang Marine Microorganism Ecological&Application Laboratory Zhejiang Ocean UniversityZhoushan 316022China

The Changjiang River Estuary(CRE)in the East China Sea suffers from seasonal hypoxia in *** vertical distributions and seasonal changes of microbial communities in the CRE were well ***,little is known about the diurnal changes of bacterial communities in the hypoxic zone of the ***,16 S rRNA gene analysis was used to explore the changes of bacterial communities in the oxic surface and hypoxic middle seawater layers during 24 h in the *** differences between the hypoxic and oxic layers were observed:the phyla Cyanobacteria,Bacteroidetes and Acidimicrobiia were enriched in the oxic layer,whereas the phylum SAR406 and the class deltaproteobacteria were more abundant in the hypoxic *** addition,some subtle diurnal variations of the bacterial relative abundance were found in both two *** relative abundance of Synechococcus increased at night,and this change was more obvious in the hypoxic *** similar trend was also found in some phototrophic and several heterotrophic bacteria,such as Rhodobacteraceae,OM60 and *** relative abundances peaked at 16:00 in the oxic layer,while the relative abundances peaked at around 7:00 and decreased until 13:00 in the hypoxic ***,the results of the present study suggest that some photosynthetic bacteria and several heterotrophic bacteria have similar diurnal variations implying the light and physicochemical heterogeneity in the course of a day are important for bacterial diurnal changes in the CRE.

关键词： bacterial communities diurnal changes hypoxic zone the Changjiang River Estuary

Incorporation of a nanotechnology-based additive in cementitious products for clay stabilisation

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第5期12卷 1056-1069页

作者： E.u.Eyo S.Ng’ambi S.J.Abbey School of Energy Construction and EnvironmentFaculty of EngineeringEnvironment and ComputingCoventry UniversityCoventryUK Faculty of Environment and Technology Department of Geography and Environmental ManagementCivil Engineering ClusterUniversity of the West of EnglandBristolUK

The mechanical performances and water retention characteristics of clays,stabilised by partial substitution of cement with by-products and inclusion of a nanotechnology-based additive called RoadCem(RC),are studied in this *** unconfined compression tests and one-dimensional oedometer swelling were performed after 7 d of curing to understand the influence of addition of 1%of RC material in the stabilised soils with the cement partially replaced by 49%,59%and 69%of ground granulated blast furnace slag(GBBS)or pulverised fuel ash(PFA).The moisture retention capacity of the stabilised clays was also explored using the soil-water retention curve(SWRC)from the measured *** confirmed an obvious effect of the use of RC with the obtained strength and swell properties of the stabilised clays suitable for road application at 50%replacement of *** outcome is associated with the in-depth and penetrating hydration of the cementitious materials by the RC and water which results in the production of needle-like matrix with interlocking filaments e a phenomenon referred to as the‘wrapping’*** the other hand,the SWRC used to describe the water holding capacity and corresponding swell mechanism of clays stabilised by a proportion of RC showed a satisfactory *** moisture retention of the RC-modified clays was initially higher but reduced subsequently as the saturation level increased with decreasing *** phenomenon confirmed that clays stabilised by including the RC are water-proof in nature,thus ensuring reduced porosity and suction even at reduced water ***,the stabilised clays with the combination of cement,GGBS and RC showed a better performance compared to those with the PFA included.

关键词： Cement Ground granulated blast furnace slag(GBBS) Fly ash RoadCem(RC) Swell Stabilisation unconfined compressive strength Soil-water retention curve(SWRC)

Trace element geochemistry and stable isotopic(δ^(13)C andδ^(15)N)records of the Paleocene coals,Salt Range,Punjab,Pakistan

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International Journal of Mining Science and Technology 2022年第3期32卷 551-561页

作者： Noshin Masood Tehseen Zafar Karen A.Hudson-Edwards Hafiz u.Rehman Abida Farooqi Environmental Geochemistry Laboratory Department of Environmental SciencesFaculty of Biological SciencesQuaid-i-Azam UniversityPO 45320Pakistan Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081China Institute of Geology University of the PunjabLahore 54590Pakistan Environment&Sustainability Institute and Camborne School of Mines University of ExeterTR109EZUK Graduate School of Sciences and Engineering Kagoshima UniversityKagoshima 890-0065Japan

The Paleocene coals of the Salt Range in the Punjab Province of Pakistan have great economic potential;however,their trace element and stable isotopic characteristics have not been studied in detail except for a few sporadic *** this study,a total of 59 coal samples of which 14 are obtained from open cast mines have been investigated for elemental composition andδ^(13)C-δ^(15)N isotopic *** contents of trace elements such as Co,Cr,Cu,Pb,Sr,Th,u,V,and Zn are 7.4,41.7,11.2,12.5,90.2,4.0,1.9,128,and 31.1 mg/kg,*** values,when compared with the World Coal Clarke values,were relatively higher in low-rank coals in comparison with Clarke values for brown ***,As(20.4 mg/kg),Co(6.6 mg/kg),Cr(22.4 mg/kg),Cu(^(13).3 mg/kg),Pb(19.2 mg/kg),Sr(^(15)4.7 mg/kg),Th(2.5 mg/kg),V(47.8 mg/kg),and Zn(75.1 mg/kg)were significantly higher in the sub-bituminous to bituminous coals of the Salt *** analysis,based on X-ray diffraction and energy dispersive X-ray spectroscopy,revealed that the studied samples contain illite,kaolinite calcite,gypsum,pyrite,and *** affinity with organic and inorganic phases of coals calculated by an indirect statistical approach indicated a positive association of ash content with Ag,Al,Co,Cr,Cs,Cu,Mn,P,Rb,Pb,Th,u,and V,suggesting the presence of inorganic components in studied ***,As,Fe,Sr,and Zn exhibit negative correlations that imply their association with the organic ***δ^(13)C andδ^(15)N isotopic range and average−24.94‰to−25.86‰(−25.41‰)and−2.77‰to 3.22‰(0.96‰),respectively,reflecting 3C type modern terrestrial vegetation were common in the palaeomires of studied coal *** addition,the trivial variations of 0.92‰and 0.45‰among^(13)C and^(15)N values can be attributed to water level fluctuations and plant assemblies.

关键词： Coal Salt Range Pakistan Geochemistry Trace elements δ^(13)C andδ^(15)N isotopes

diagnostic performance of C-reactive protein level and its role as a potential biomarker of severe dengue in adults

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Asian Pacific Journal of Tropical Medicine 2020年第8期13卷 358-365页

作者： Raghavendra Rao Snehal Nayak Akhilesh K Pandey Shobha u Kamath department of Medicine Kasturba Medical CollegeManipalIndia Manipal Academy of Higher Education ManipalIndia department of Biochemistry Kasturba Medical CollegeManipalIndia department of Community Medicine Kasturba Medical CollegeManipalIndia

Objective: To determine the relationship between C-reactive protein(CRP) level and the severity of dengue and the potential use of CRP in predicting acute dengue ***: A prospective observational study was performed on dengue patients admitted to a tertiary care hospital in southern India. All patients of age above 18 years, diagnosed with dengue were included in the study. The detailed laboratory parameters pertaining to dengue were recorded. CRP levels were estimated and compared between groups i.e. severe and non-severe dengue. CRP cut-off value was detected using the receiver-operator ***: Totally 98 patients with a mean age of 40 years were included. Among them, 11.2% of the patients suffered from severe dengue, 54.1% of the cases had non-severe dengue without warning signs, and 34.7% had non-severe dengue with warning signs. The median CRP was significantly higher in patients with severe dengue compared to patients with non-severe dengue(96.2 mg/d L vs. 5.3 mg/d L). univariate logistic regression analysis showed that the odd’s ratio(OR) of CRP was 1.053(P≤0.001, 95% CI=1.029-1.078). CRP at a cutoff value of 21.6 mg/L(0.929 AuC) had excellent sensitivity(100%) and specificity(81.6%) in predicting severe dengue infection. Multivariate logistic regression analysis showed that CRP(OR=1.089, P=0.013) and ALT(OR=1.010, P=0.034) were statistically significant independent predictors of dengue ***: CRP level could be used as a potential biomarker to predict severity of dengue in adults.

关键词： Vector-borne Arbovirus Inflammation Biochemical Tropical disease