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An investigation is made of selective withdrawal of a linear stratified fluid from a line sink in a channel of depth d. The flow is characterized by a densimetric Froude number F = Q/Nd2, where Q is the discharge per unit width and N is the Väisälä frequency. The dynamics of establishment of flow are investigated theoretically. Analytic results are obtained from a linearized theory based on a systematic perturbation scheme for small values of F. These results lead to a proper identification of the successive arrival of ‘columnar disturbance modes’ as the mechanism responsible for the development of flow concentration in the withdrawal region. Viscous and diffusive effects are also examined. For larger times and higher discharges (higher values of F), nonlinear effects become important, and the full Navier-Stokes equations are now solved numerically by a finite-difference procedure in a ‘stretched’ co-ordinate system. The solutions indicate that the establishment of the steady flow field is due to the successive arrival and interaction of ‘columnar disturbance modes’. Steady-state solutions are also presented, and a similarity profile is obtained. Comparison of the theoretical findings with experimental results are presented in part 2. Agreement with experimental measurements is found to be excellent.

Experiments were conducted to examine the development and establishment of the withdrawal current in the selective withdrawal of a stratified fluid from a line sink. The experiments were performed in a Plexiglas channel 30·5 ft long 14 in. wide, and filled with a linearly stratified salt solution to a depth of 18 in. The line sink was located at mid-depth. The flow was symmetric about the middepth. Velocity measurements and flow visualization were obtained by neutrally buoyant liquid droplets and vertical dye lines. Density measurements were made by a salinity probe. The development of the upstream velocity field was found by measurement to be brought about by the successive arrival of ‘columnar disturbance modes’, discussed in part 1. Agreement with the theoretical predictions is excellent. A similarity profile of the steady-state horizontal velocity is obtained, and the Froude number based on the thickness of the flowing zone is found to approach a constant value in the essentially inviscid region. The results are compared with field data from the Tennessee Valley Authority (TVA) reservoirs.

Ion–molecule reactions in mixtures of CH4 and CD4 at pressures up to about 0.65 torr have been carried out in a single ion source of a quadrupole mass filter. From the isotope distribution in the ethyl ions, it is evident that randomization occurs in the complex of methyl ions with methane. There is no evidence for reaction of ethyl ion with methane. Similarly, methane ions react with methane to form CH5+, CH4D+, CD4H+, and CD5+. The ratios of products are very nearly what would be expected from reactions of methane ion with methane rather than from transfer of protons and deuterons from methanium ion. H and D atoms appear to be transferred at equal rates but deuterons are transferred at only about six‐tenths the rate of transfer of protons.

Sex differences in susceptibility to high pressure oxygen (OHP)-induced convulsions were observed in mature rats. Male rats convulsed significantly earlier than did females. After adrenalectomy, seizures disappeared in most females and some male rats. The number of adrenalectomized male rats which resisted OHP-induced convulsions increased from 40 % to 91 % when they were treated with estradiol subcutaneously. Rats which do not convulse during the exposure to OHP eventually develop pulmonary edema and congestion and die. Strain variations in respect to susceptibility to oxygen poisoning and the contreversal nature of OHP and electroshock-induced convulsions in response to steroid hormones are discussed.

By operating the ion source of a mass spectrometer at pressures above 0.2 Torr, equilibrium constants have been obtained for the proton transfer reaction of methanol with benzene, and of both methane thiol and dimethyl ether with toluene and the three xylenes. The resulting free energies when combined with the known proton affinities of the reference compounds (and assuming zero entropy of reaction) gives the values for the proton affinities. (Author)

The effects of digitonin and digitoxin on the phospholipid metabolism of mammalian tissue culture cells have been studied. Digitonin stimulates the incorporation of inorganic orthophosphate- 32 P into the total phospholipid. The phospholipid was then separated on silicic acid-impregnated glass paper chromatography, and the specific activity of each phosphatide was calculated. It was found that digitonin caused a linear increase in the specific activity of phosphatidyl inositol and diphosphatidyl glycerol at the time periods studied. The increase in the specific activities of phosphatidyl choline and phosphatidyl ethanolamine was delayed but to the same extent (more than twofold) after 120-min incubation. The specific activities of phosphatidyl serine and sphingomyelin were low and not significantly affected. The increase was similar in specific activity values of phospholipids of digitonintreated HeLa cells as that of the controls in the nuclear, mitochondrial, and microsomal fractions. Digitonin failed to stimulate the incorporation of palmitic-l- 14 C acid into the phospholipids of HeLa cells. A nonsteroid surface-active agent (Triton X-100) did not stimulate the incorporation of 32 P, into the phospholipids of HeLa cells, but other steroids, desoxycholate, and estradiol did stimulate such incorporation of 32 P i . Digitoxin had little effect on the phospholipid labeling of HeLa cells. However, digitoxin stimulated the incorporation of 32 P, into phosphatidyl inositol and sphingomyelin fraction of human heart culture cells. The specific interaction of various steroids with the target-cell membranes and its relation to phospholipid metabolism is discussed.

In carbon monoxide at pressures above 0.2 torr, the principal product ion is C2O2+ formed by a three‐body process. The rate constant for the reaction is 1.43 × 10−28 cm6 molecule−2·sec−1. Above about 0.8 torr, the reaction appears to approach equilibrium with an equilibrium constant of 1482 referred to 1 atm as standard. At pressures of methane above 0.2 torr and small additions of CO, the only reaction observed in the protonation of CO by CH5+ with a rate constant of 5.54 × 10−10 cm3 molecule−1·sec−1. All other reactions are endothermic and are not observed. At pressures of carbon monoxide above 0.2 torr, the addition of small amounts of methane results in an H‐atom transfer reaction to CO+ with a rate constant of 13.7 × 10−10 cm3 molecule−1·sec−1. In addition, C2O2+ reacts to form HCO+, C2H3O+, and C3H3O+ with rate constants of 9.44, 4.37, and 0.76 × 10−10 cm3 molecule−1·sec−1, respectively.

By employing elevated pressures in the ion source of a quadrupole mass filter, it is shown that D3S+ does not transfer a deuteron to D2O and that D3O+ transfers a deuteron to D2S. Studies were carried out in most instances under conditions where the reactant ion undergoes 30–60 collisions before reacting. Thus, most excess energy should have been removed. The transfer of deuteron from D3O+ to D2S appears to go to equilibrium with an equilibrium constant of 14.4 which corresponds to a heat of reaction of 1.8 kcal/mole. From this we deduce the proton affinity of water to be 168 kcal/mole.

An equation for determining the dispersion relations of the surface plasma oscillations has been derived for the most general case of multilayers. The equation is given in a very simple form of the vanishing of the trace of a product of 2×2 matrices of recursive type.

The transmission coefficient of a light polarized in the plane of incidence through a metal foil is calculated, taking into account the excitation of the longitudinal plasma oscillations in addition to the transversal waves inside the metal.

A time study of the incorporation of(32)P(i) into the phospholipids of HeLa, KB, human heart, and liver tissue-culture cell lines has been carried out. The incorporation of(32)P(i) at various time-intervals into the phospholipids of nuclei, mitochondria, and microsomes of HeLa and KB cells was investigated. The labeling of the isotope into the phospholipids was divided into three groups.The first had two components: phosphatidyl inositol and polyglycerol phosphatides, which showed the greatest incorporation of the isotope as demonstrated in the specific activity values and the percentage of total radioactivity after 15 to 30 minutes of incubation. A second group was composed of the major phospholipids of all tissue-culture cell lines studied, phosphatidyl choline, and phosphatidyl ethanolamine. At first, there was a delayed labeling of these phospholipids; however, after one hour of incubation, a rapid increase was shown in the incorporation of(32)P(i). A third group of lipids containing sphingomyelin and phosphatidyl serine demonstrated low specific activity values.The phospholipids of the subcellular fractions, nuclei, mitochondria, and microsomes, had a high degree of incorporation of the isotope into the individual phospholipids and probably represented an active process in the membranes of these cellular units or a renewal of the biological membrane structures.

Since comprehensive evaluation model was introduced by Wang in 1984, the comprehensive evaluation model has many successful applications in real life. But some examples show the inefficiency of the comprehensive evaluation model. In order to process these problems, in this paper, we introduce two concepts of standardized fuzzy set and normalized fuzzy set, propose a novel method to improve the comprehensive evaluation model and its algorithm. Finally, we use three numerical examples to illustrate our proposed model reasonable and point out that our proposed method can avoid some inefficiencies in applications.

Chemical composition of subcellular components of HeLa, KB, human heart and liver tissue-culture cell lines have been studied.The concentration of RNA, protein and phospholipid (mug/mug of DNA) of total subcellular particles was similar for all four cell lines studied. The greatest RNA concentration and lowest protein concentration is found in the microsomes as compared to the other subcellular fractions of HeLa and KB cells.The lipid P/Protein N ratio of mitochondria was greater than the other subcellular fractions from tissue-culture cell lines studied. Phosphatidyl choline and phosphatidyl ethanolamine are the major phospholipids with the former more predominant in all of the subcellular fractions of tissue-culture cells studied. Phosphatidyl inositol, phosphatidyl serine, sphingomyelin and polyglycerol phosphatide were shown to be present. Phosphatidyl choline composition (per cent of total lipid-P) is greatest in the microsomes when compared with the other subcellular fractions obtained from all of the cell lines studied except the nuclear fraction of human liver cells. Correspondingly, the mitochondrial fraction for all of the tissue culture cell lines contains the greatest composition of phosphatidyl ethanolamine except for the human liver and heart cells. The mitochondrial fraction contains the lowest amount of phosphatidyl inositol. Polyglycerol phosphatide is mainly present in the mitochondrial fraction of the tissue-culture cells.

Page 20 missing from the thesis. This work was undertaken to evaluate neutron activation analysis as a technique for simultaneous determination of Ru and Os in sulfide minerals by counting the γ radiation of 97Ru and 103Ru, and the β^-radiation of 191Os and 193Os. The samples studied were collected from the Strathcona and Frood-Stobie Cu-Ni sulfide deposits of Sudbury. Sulfide minerals, including pyrrhotite, chalcopyrite, pentlandite and cubanite were separated from samples including representatives of both ore grade and non-commercial material. The minerals were analysed for Ru and Os to determine their concentration ranges in these sulfides, the degree of geochemical coherence of the metals in sulfides from both high grade ore zones and weakly mineralized rocks and their distribution between coexisting sulfides. Thesis Master of Science (MSc)

Doctorat en Sciences, info:eu-repo/semantics/nonPublished

Objective: To analyse and discuss the related aspects of the nursing effect of comprehensive nursing intervention in elderly patients with severe pneumonia. Methods: 150 cases of senile severe pneumonia were randomly divided into observation group and control group. 75 patients were distributed to each control group and observation group, the control group was applied with conventional nursing intervention, observation group was applied with comprehensive nursing intervention, the two groups of clinical efficacy and quality of life and related care satisfaction were compared. Results: The effective rate of treatment was 90.67% (68/75) in the observation group, which was significantly higher than that in the con-trol group (74.67%, 56/75), P