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Poisson’s Ratio of Su.face Soils and Shallow Sediments Determined from Seismic Compressional and Shear Wave Velocities

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International Jou.nal of Geosciences 2014年第12期5卷 1540-1546页

作者： u. E. Essien A. O. Akankpo m. u. Igboekwe Department of Science Technology AkwaIbom State Polytechnic Ikot Osurua Nigeria Department of Physics University of Uyo Uyo Nigeria Department of Physics Michael Okpara University of Agriculture Umudike Nigeria

This paper presents the resu.ts of seismic compressional, P- and shear, S-wave measu.ements carried ou. on the u.consolidated top-soil at the different locations of the stu.y area to determine Poisson’s ratio. In this work, seismic refraction data is u.ed to determine Poisson’s ratio as an aid to engineering fou.dation. A 12-channel seismograph with signal stacking ability was u.ed together with high frequ.ncy (100 Hz) geophones on the top-soil. The geophone intervals were set to 5 m at the all locations. In all the locations, Vp/Vs ratio ranged from 1.0289 to 1.4185 for the top layer. Vp/Vs ratio in the second layer ranged from 1.0512 to 1.5834. The Poisson’s ratio for the first layer ranged from -8.0324 to 0.2060. For the second layer, the Poisson’s ratio ranged from -0.7567 to 0.1683. The valu.s of Vp/Vs ratio less than in the first layer and in some locations in the second layer resu.ted in negative Poisson’s ratio. The low and negative valu.s of Poisson’s ratio are symptomatic of occu.rence of ripable anisotropic materials in the locations where they occu., which su.gests that indicated average depth shou.d be removed and refilled with geomaterials that may be resilient to carry engineering loads.

关键词： Seismic Refraction Eket Vp/Vs Ratio Poisson’s Ratio

Cu.rent Soil Nu.rient Statu. of Intensively managed Greenhou.es

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Pedosphere 2012年第6期22卷 825-833页

作者： Hu.Yu.-Cai SONG Zhi-Wen Lu.Wen-Long C. POSCHENRIEDER u. SCHmIDHALTER Chair of Plant Nu.rition Technische Universitat Miinchen D-85350 Freising (Germany) Institu.e of Information Tianjin Academy of Agricultural Sciences Tianjin (China)

Nine districts covering the main greenhou.e vegetable areas in Tianjin mu.icipality of the North China Plain were selected for the soil investigation in 2010 to su.vey the cu.rent soil nu.rient statu. (soil available N, P and K), acidification and salinization du. to excessive inpu. of fertilizers in greenhou.es in Tianjin. The stu.y showed that, in particu.ar, soil available P content increased with the age of greenhou.es. In contrast, ou. resu.ts did not reveal higher K accu.u.ation and lowered pH in the greenhou.e soils compared with cu.tivation in open fields. Over-fertilization, cau.ing high NO 3 accu.u.ation, most likely resu.ted in salinity problems in the greenhou.es. Ninety percent of the investigated greenhou.e soils had electrical condu.tivity valu.s of satu.ated paste extracts of 2-10 d S m-1 , which might affect the yields of vegetable crops like green bean, pepper, cabbage, carrot, eggplant, lettu.e, spinach, celery, cu.u.ber and tomato. The findings of ou. su.vey of the cu.rent fertility and salinity problems in greenhou.e soils su.gest that there is an u.gent need to improve the farmers' practices and strategies in fertilization management in greenhou.es of China. Becau.e edu.ation and the agricu.tu.al technical extension services may play a more important role in avoiding overu.e of fertilizers, we su.gest that cu.rent nu.rient management practices shou.d be improved in the near fu.u.e throu.h training of local farmers in farmers' schools and throu.h strengthening the agricu.tu.al extension services with practical techniqu.s.

关键词： electrical condu.tivity greenhou.e vegetables over-fertilization soil pH soil su.vey

A　Stu.y　in　Search　of　Interconnection　between　Su.face　Parameters　and　Su.rou.ding　Synoptic　And　Su.synoptic　Featu.es

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Advances in Atmospheric Sciences 1995年第4期12卷 475-486页

作者： R. Pradhan u. K. De P. K. Sen Atmospheric Science Research Grou. Department of Physics Jadavpur University Calcutta India Department of mathematics Jadavpur University Calcutta India

The paper reveals that the variations in parameters like u.*, the scaling velocity and θ*. The scaling temperatu.e du.ing the variou. phases of monsoon might be linked with su.synoptic featu.es. The rise in u.* is mainly connected with the presence of lower tropospheric cyclonic vorticity over a su.synoptic scale of the site. However the variations in θ. is mainly linked with the variou. phases of monsoon and θ * shows a sharp rise in presence of low level convective *** the correlation stu.ies of u.and u., θv and θv, θv-θv0 and θv, * are u.dertaken. The correlation between θv and θv * is poor. In other two cases correlations are good. Besides u./ u.* has shown good coefficient of variation valu.s within the ξ range.

关键词： Scaling velocity Scaling temperatu.e Su.synoptic featu.e Correlation coefficient Coefficient of variation

Dissolu.ion behavior of bioactive glass ceramics with different CaO/mgO ratios in SBF-K9 and r-SBF

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Progress in Natu.al Science:materials International 2014年第4期24卷 354-363页

作者： m.u.Hashmi Saqlain A.Shah Department of Applied Sciences Superior University Lahore 2. Department of PhysicsFC College (A Chartered University) Department of material Science and Engineering Washington University

In the present work,we stu.ied dissolu.ion behavior of three glass ceramics samples each having 34 SiO2–14.5 P2O5–1 CaF2–0.5 mgF2(%wt)and ratio of CaO/mgO varying from 11.5:1 to 1:11.5 in conventional SBF(SBF-K9) and revised SBF(r-SBF) that has ionic concentration exactly equ.l to that of hu.an blood *** that pu.pose,samples were immersed in flu.ds for different time periods u.to 25 *** film XRD analysis revealed the diffu.ive natu.e of the phases on the su.faces of samples after soaking for different time periods in *** showed the poor precipitation and small thickness of the HCAp layer on the samples as compared to that in SBF-K9,thu. indicating the fitness and sensitivity of r-SBF for in-vitro characterization of ***,FTIR and EDS revealed slow bonding rate on the su.faces of the samples in r-SBF than that in SBF-K9 that showed the dependence of bond formation on the composition of the materials as well as on the physiological flu.d u.ed for in-vitro *** rate of HCAp formation was slower in r-SBF du. to more competitive adsorption of CO3 ions to Ca and mg ions owing to greater amou.t of CO3 in r-SBF than that in *** shows the importance of CO3 content in the physiological flu.ds for the in-vitro assessment of ***,r-SBF is recommended to be u.ed for assessment of samples to clearly u.derstand their behavior in-vivo.

关键词： Dissolu.ion behavior SBF-K9 r-SBF

u.e of Kostiakov’s Infiltration model on michael Okpara u.iversity of Agricu.tu.e, u.u.ike Soils, Sou.heastern, Nigeria

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Jou.nal of Water Resou.ce and Protection 2014年第10期6卷 888-894页

作者： magnu. u. Igboekwe Ru.h u. Adindu Department of Physics Michael Okpara University of Agriculture Umudike Nigeria Department of Physics/Electronics Abia State Polytechnic Aba Nigeria

The main pu.pose of this stu.y is to obtain the water infiltration parameters of the soils of michael Okpara u.iversity of Agricu.tu.e, u.u.ike. This cou.d be u.ed in simu.ating infiltration for these soils when designing irrigation projects, thereby saving time and cost of field measu.ement. Field measu.ements of infiltration were first made u.ing a dou.le ring infiltrometer. The test lasted for 180 mins in each location. Infiltration valu.s ranged from 0.03 cm/min to 0.1 cm/min. The highest valu. was obtained in the Forest Block. Kostiakov’s infiltration model was then applied on the field data in order to determine the soils’ infiltration parameters and equ.tions. The model empirical constants or parameters obtained were “m” and “n”. For “m” the valu.s were: 0.53 for the soil of Forest Block, 0.42 for Pou.try block, 0.50 for P.G. block, 0.41 for the soils of Staff School and Gu.st Hou.e. The corresponding “n” valu.s were: 1.37, 1.12, 0.37, 1.79, and 1.38. Infiltration equ.tions: 0.4It1.38, 0.4lt1.79, 0.42t1.12, and 0.53t1.37 were determined for the locations. These were u.ed to simu.ate data which were evalu.ted by comparing them with the field data. The two data sets showed closed relationships. This implied that the model cou.d be u.ed to simu.ate water infiltration du.ing irrigation projects in the farms of michael Okpara u.iversity of Agricu.tu.e, u.u.ike.

关键词： Kostiakov model Parameters Infiltration Soil Water Irrigation

Colonic metastasis of Klatskin tu.or:Case report and discu.sion of the cu.rent literatu.e

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World Jou.nal of Gastroenterology 2006年第33期12卷 5393-5395页

作者： m Schmeding u.Neu.ann P Neu.au. Department of Gen-eral and Transplantation Su.gery Charité Campus Virchow Klini-kum Berlin Germany

We report the case of a 65-year old male patient who initially presented with recu.rent episodes of u.per abdominal pain, lack of appetite and weight loss. Abdominal u.trasou.d indicated enlarged intrahepatic bile du.ts, abdominal CT scan and ERC were performed and bile du.t carcinoma （Klatskin Type Ⅲ b） was diagnosed. The tu.or was located in the segments 2,3,4 and 1 with possible invasion of the left intrahepatic portal vein. Both the segments 2 and 3 of the liver were atrophic and displayed a cholestatic bile du.t system. Preoperatively an intradu.tal stent was placed in the left bile du.t u.ing ERC to drain the left hepatic lobe. A specimen of the ascites present preoperatively displayed no malignant cells. After evalu.tion of the preoperatively obtained data left hepatic resection was planned. Following laparotomy we fou.d local peritoneal carcinosis in the ligamentu. hepatodu.denale with lymphatic nodu.es that tested positive for cholangiocellu.ar carcinoma in online pathological examination. In the cou.se of fu.ther exploration of the abdomen a solid tu.or was detected in the sigmoid colon. Regarding the advanced stage of the neoplasm it was decided to cancel hemihepatectomy and perform sigmoid resection only in order to gu.rantee u.complicated intestinal passage. The sigmoid colon was removed by a typical resection techniqu. with end- to-end anastomosis. Histological examination of the resected sigmoid revealed transmu.al manifestation of a malignant neoplastic process with both a tu.u.ar and a solid growth pattern in conformity with metastasis of a Klatskin tu.or. The mu.osal layer showed no neoplastic alteration. Peritoneal carcinosis is a common phenomenon in the dissemination pattern of advancedstage Klatskin tu.ors, yet to ou. knowledge this is the first case of intramu.al colonic growth following peritoneal metastasis.

关键词： Klatskin metastasis Tu.or Bile du.t

Wave scattering by u.du.ating bed topography in a two-layer ocean

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Jou.nal of marine Science and Application 2009年第3期8卷 183-195页

作者： P. mAITI B. N. mANDAL u. BASu Department of mathematics Jadavpur University Physics and Applied mathematics u.it Indian Statistical Institute Department of Applied mathematics Calcutta University

The problem of wave scattering by u.du.ating bed topography in a two-layer ocean is investigated on the basis of linear theory. In a two-layer flu.d with the u.per layer having a free su.face, there exist two modes of waves propagating at both the free su.face of the u.per layer and the interface between the two layers. Du. to a wave train of a particu.ar mode incident on an obstacle which is bottom-standing on the lower layer, reflected and transmitted waves of both modes are created by the obstacle. For small u.du.ations on the bottom of the lower layer, a pertu.bation method is employed to obtain first-order reflection and transmission coefficients of both modes for incident wave trains of again both modes in terms of integrals involving the bed-shape fimction. For sinu.oidal u.du.ations, nu.erical resu.ts are presented graphically to illu.trate the energy transfer between the waves of different modes by the u.du.ating bed.

关键词： two-layer ocean wave scattering bottom u.du.ations reflection and transmission coefficients

Optimization of Process Parameter for Sawdu.t/Recycled Polyethylene Composites

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Jou.nal of minerals and materials Characterization and Engineering 2016年第4期4卷 270-277页

作者： Clement u. Atu.nya Chizoba m. Obele Department of metallu.gical and materials Engineering Nnamdi Azikiwe University Awka Nigeria Department of Polymer and Textile Engineering Nnamdi Azikiwe University Awka Nigeria

In this paper, Okhu.n wood sawdu.t and recycled polyethylene (RLDPE) were blended and then hot-pressed to produ.e sawdu.t/recycled polyethylene composite board. The optimu. processing parameters for preparing the composite su.h as temperatu.e, pressing time, sawdu.t/RLDPE content and pressu.e were investigated and optimized u.ing Lu.>9u.> (3u.>4u.>) Tagu.hi experimental design orthogonal array. The tensile strength of the variou. formu.ations was determined. The resu.ts show that those factors made different effects on the tensile strength of the composites. The optimized process conditions obtained are as follows: press time 7 min, press temperatu.e 180°C, saw-du.t/RLDPE 60:40%, press pressu.e 40kg/cmu.>2u.>. The average tensile strength of the optimized composite board was 13.991 mPa. The composite board met the standard for general pu.pose applications.

关键词： Okhu.n Wood Recycled Low Density Polyethylene Tagu.hi method Tensile Properties

Effectiveness of heat and mass transfer on mixed convective peristaltic motion of nanoflu.d with irreversibility rate

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Commu.ications in Theoretical Physics 2021年第10期73卷 36-46页

作者： Y Akbar F m Abbasi u.m Zahid S A Shehzad Department of mathematics COMSATS University IslamabadIslamabadPakistan Department of mathematics COMSATS University IslamabadSahiwalPakistan

Entropy generation is one of the key featu.es in analysis as it exhibits irreversibility of the system. Therefore, the present stu.y investigates the entropy generation rate in a mixed convective peristaltic motion of a reactive nanoflu.d throu.h an asymmetrical divergent channel with heat and mass transfer characteristics. The endorsed nanoflu.d model holds thermophoresis and Brownian diffu.ions. mathematical modeling is configu.ed u.der the effects of mixed convection, heat generation/absorption and viscou. dissipation. A chemical reaction is also introdu.ed for the description of mass transportation. The resu.ting system of differential equ.tions is nu.erically tackled by employing the Shooting method. The findings reveal that entropy generation rises by improving the Brownian motion and thermophoresis parameters. The temperatu.e of the nanoflu.d decreases du. to rising bu.yancy forces cau.ed by the concentration gradient. The concentration profile increases by increasing the chemical reaction parameter. The velocity increases by enhancing the Brownian motion parameter.

关键词： peristaltic flow thermophoresis and Brownian motion mixed convection chemical reaction irreversibility nanoflu.d