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901.
N.K. Joshi T.K. Thiagarajan V.K. Rohatgi 《International Communications in Heat and Mass Transfer》1989,16(6):875-882
The effect of thermal boundary layer on radiative heat transfer considering nongray nonisothermal plasma has been calculated for potassium seeded watergas combustion plasma. The effect of combustion species concentration and seed concentration on radiative flux under the equilibrium flow and frozen flow condition has been studied. It has been estimated that reduction in radiative flux due to cold boundary layer may be upto 25%. 相似文献
902.
The polymeric ligand (resin) was synthesized by condensation of 2‐hydroxy‐4‐ethoxybenzophenone with ethane diol in the presence of polyphosphoric acid as a catalyst at 145°C for 10 h. The synthesized resin was used to study its ion exchange efficiency and to synthesize its polychelates with 4f‐block elements. The resin and its polychelates were characterized on the basis of elemental analyses, electronic spectra, magnetic susceptibilities, IR, NMR, and thermogravimetric analyses. The molecular weight was determined using number–average molecular weight (Mn ) by a vapor pressure osmometry (VPO) method. Ion‐exchange studies at various concentrations of different electrolytes, pH, and rate have been carried out for f‐block elements. Antimicrobial activity of all polychelates and catalytic activity of selected polychelates in organic synthesis have been studied. It is observed that resin can be used as an ion‐exchanger and polychelates are found to be an efficient catalysts and antimicrobial agents. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
903.
M Yebra GC Parry S Str?mblad N Mackman S Rosenberg BM Mueller DA Cheresh 《Canadian Metallurgical Quarterly》1996,271(46):29393-29399
The urokinase plasminogen activator (uPA) interacts with its cell surface receptor (uPAR), providing an inducible, localized cell surface proteolytic activity, thereby promoting cellular invasion. Evidence is provided for a novel function of cell surface-associated uPA.uPAR. Specifically, induction of cell surface expression of uPA. uPAR by growth factors or phorbol ester was necessary for vitronectin-dependent carcinoma cell migration, an event mediated by integrin alphavbeta5. Cell migration on vitronectin was blocked with either a soluble form of uPAR, an antibody that disrupts uPA binding to uPAR, or a monoclonal antibody to alphavbeta5. Moreover, plasminogen activator inhibitor type 2 blocked this migration event but did not affect adhesion, suggesting a direct role for uPA enzyme activity in this process and that migration but not adhesion of these cells is regulated by uPA.uPAR. Growth factor-mediated induction of uPA.uPAR on the carcinoma cell surface promotes a specific motility event mediated by integrin alphavbeta5, since cells transfected with the beta3 integrin subunit expressed alphavbeta3 and migrated on vitronectin independently of growth factors or uPA.uPAR expression. This relationship between alphavbeta5 and the uPA.uPAR system has significant implications for regulation of motility events associated with development, angiogenesis, and tumor metastasis. 相似文献
904.
N. V. Joshi Alicia Serfaty 《Journal of Infrared, Millimeter and Terahertz Waves》1989,10(9):1077-1088
Important parameters of the photosensors such as Noise Equivalent Power (NEP) and detectivity depend upon the magnitude of the signal to noise ratio. Recent improvements in the techniques of measurement in digitized form permit to process noise statistically with a suitable procedure and increase the detection capability more than expected from the conventional definition. 相似文献
905.
The frequency of micronuclei was evaluated in the bone marrow of mice of either sex administered with 0, 0.625, 1.25, 2.5, 5, 10, 20, 40 and 80 mg/kg b.wt of lead nitrate at 12, 24 and 36 h post-treatment. The frequency of micronucleated polychromatic erythrocytes (MPCE) and micronucleated normochromatic erythrocytes (MNCE) increased significantly at 12, 24 and 36 h after treatment with lead nitrate compared to non-drug treated controls. The frequency of micronuclei did not show a dose related increase and the elevation in the frequency of micronuclei was fluctuating type. One important observation which emerged from this study was that the male mice were more sensitive to the induction of micronuclei compared to female mice. This was evidenced by higher frequencies of MPCE in males than females at all the doses for all the post-treatment time periods. The lead nitrate treatment resulted in a spurt in the erythropoiesis as is evidenced by a significant increase in the ratios of polychromatic to normochromatic erythrocytes (P/N ratio) compared to non-drug treated controls at 12, 24 and 36 h post-treatment. The P/N ratio was significantly higher in females than males at 12 and 24 h post-treatment. 相似文献
906.
Sadanand B. Joshi Richard A. Pethrick Ray Gilmore Lawrence W. Yates David Hayward 《The Journal of Adhesion》1997,62(1):281-315
High and low frequency dielectric measurements are reported on adhesively bonded aluminum structures aged by exposure to moisture over an extended period of time. The changes observed are interpreted in terms of initially water diffusing into the adhesive layer and there is little evidence of changes occurring to the surface oxide layer. Differences in the form and rate of change of the dielectric signature reflect the effects of the pretreatment and matrix resin on the water diffusion process. A good correlation is observed between the time domain data and the increased dielectric permittivity resulting from ingress of moisture into the adhesive bond. The paper illustrates the use of high frequency dielectric measurements in non-destructively probing adhesive bonds and indicates the potential for in-situ applications. 相似文献
907.
PM Grosheide R del Canho RA Heijtink AS Nuijten J Zwijnenberg JR B?nffer YW Wladimiroff MJ Botman JA Mazel GC de Gast 《Canadian Metallurgical Quarterly》1993,147(12):1316-1320
OBJECTIVE: To assess the efficacy of late active immunization against hepatitis B concomitant with diphtheria, pertussis, tetanus, and polio vaccine in high-risk infants receiving hepatitis B immune globulin at birth. DESIGN: Randomized study of infants born to mothers positive for hepatitis B surface antigen (HBsAg) and hepatitis Be antigen (HBeAg). SETTING: Three large city hospitals and one rural area providing prenatal care and obstetric services. SUBJECTS: Eighty neonates of HBsAg- and HBeAg-positive carrier mothers received 0.5 mL/kg of body weight hepatitis B immune globulin within 2 hours of birth and hepatitis B vaccine (10 micrograms) at 0, 1, 2, and 11 months of age (group A) or at 3, 4, 5, and 11 months of age concomitant with diphtheria, pertussis, tetanus, and polio immunization (group B). A second dose of hepatitis B immune globulin was given to infants on schedule B at 3 months. MAIN OUTCOME MEASURES: Blood samples were collected at 0, 3, 6, 11, and 12 months of age and tested for antibodies against hepatitis B core antigen and HBsAg. Follow-up visits were scheduled annually up to 5 years of age. RESULTS: Eight infants were excluded from analysis. During the study period, six children became HBsAg carriers, three in each group, which corresponds to a 5-year incidence of infection of 9% and 8% for groups A (three of 35) and B (three of 37), respectively. Subclinical infections (persistent anti-HBc positivity beyond month 12 or appearance of anti-HBc) were encountered in another eight infants (four in each group). CONCLUSION: Late active immunization starting at 3 months of age appears to provide similar protective efficacy as active immunization starting at birth when combined with hepatitis B immune globulin at 0 and 3 months of age. 相似文献
908.
Joshi Kuncheria K. K. Aravindakshan 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1993,57(1):43-47
The cobalt(II), nickel(II) and copper(II) complexes of N-Isonicotinoyl-3-methyl-4-(p-hydroxybenzilidene)-2-pyrazolin-5-one (IMHBP) with different counter anions have been prepared and characterized. An octahedral geometry has been assigned to the cobalt(II) and nickel(II) complexes and a square-planar structure to the copper(II) complexes. IMHBP acts as a neutral bidentate ligand in all these complexes by coordinating through the oxygen atoms of the amide group and carbonyl at position-5. The other coordination sites are satisfied by anions alone or anions and water molecules. The ligand and the complexes were screened for their possible antitumour activity. The copper(II) complexes are appreciably active in reducing mice tumours. 相似文献
909.
MT Fierro M Bertero M Novelli A Appino GC Doveil S Colonna MG Bernengo 《Canadian Metallurgical Quarterly》1993,3(2):127-131
Violence in the workplace is sometimes a manifestation of an untreated psychiatric disorder. Paranoid personality disorder, paranoid schizophrenia, and delusional (paranoid) disorder are three psychiatric syndromes in which paranoid ideation is a prominent feature. While the vast majority of people with these conditions are not violent, paranoid workers can exhibit violent behavior as a reaction to beliefs that co-workers or supervisors are threatening or persecuting them. Three cases are described to illustrate the clinical presentation of these disorders and their management in an occupational setting. 相似文献
910.
GC Xie 《Canadian Metallurgical Quarterly》1993,9(3):201-3, 238
This paper reports a new technique to repair defects of the lip. It has been done in nine patients (2 upper lips and 7 lower lips), and the resultant oral configuration and function are satisfactory. The design and procedure are described in detail. The advantage of the method, the point for attention in performing the operation, and some problems in the repair of vermilion are discussed. 相似文献