Showing papers on "Deposition (chemistry) published in 1969"
Journal Article•
81 citations
66 citations
63 citations
57 citations
55 citations
01 Jan 1969
39 citations
TL;DR: In this paper, the growth of 2H silicon carbide showing temperature profile along susceptor as an affecting factor is discussed, along with the effect of temperature profile on susceptor temperature.
Abstract: Crystal growth of 2H silicon carbide showing temperature profile along susceptor as affecting factor
34 citations
TL;DR: The chloride system assumed by the writers (ibid., v. 63, no. 6, p. 622-635, 1968) is too simple as a model for the many complex natural systems with As, Sb, Te, and S as discussed by the authors.
Abstract: The chloride system assumed by the writers (ibid., v. 63, no. 6, p. 622-635, 1968) is too simple as a model for the many complex natural systems with As, Sb, Te, and S. Great acidity is not necessary if associated Fe is of local derivation, which is consistent with abundance of carbonate in some gold ores. Dilatancy and related pressure effects are probably more important than temperature.
33 citations
TL;DR: In this paper, the radial variation of deposit thickness on a rotating disk electrode was measured for deposition of copper from a solution and the results confirm the theory of nonuniform current distribution on such electrodes below the limiting current.
Abstract: The radial variation of deposit thickness on a rotating disk electrode was measured for deposition of copper from a solution and . The results confirm the theory of nonuniform current distribution on such electrodes below the limiting current.
30 citations
01 Nov 1969
TL;DR: The chemistry of carbonate deposition in freshwater is relatively well understood as discussed by the authors, however, often occur combined in complex mechanisms, and a variety of the fossil and recurvative processes in nature often occur in complex ways.
Abstract: The chemistry of carbonate deposition in freshwater is relatively well understood. Chemical processes in nature, however, often occur combined in complex mechanisms. A variety of the fossil and rec...
TL;DR: A series of radiocarbon dates from critical levels in a pollen diagram from a site near Scourie, Sutherlandshire, proves the recorded events to be much younger than the trend of the pollen curves would suggest.
Abstract: Summary
A series of radiocarbon dates from critical levels in a pollen diagram from a site near Scourie, Sutherlandshire, proves the recorded events to be much younger than the trend of the pollen curves would suggest. Evidence of pine forest growing in the area during the late Atlantic and Sub-boreal confirms earlier observations that these forests persisted in north-west Scotland later than in many other parts of the British Isles. The extremely slow rate of accumulation between about 420 cm and 455 cm, 1320 years, implies a break in deposition, but there is no biostratigraphic or lithostratigraphic evidence of this.
01 Jan 1969
01 Jan 1969
TL;DR: Mainly central deposition was found with large particles, rapid air flow, or shallow breathing, and clearance was faster when deposition was central, but between the first two groups, Group 1 had faster clearance; between Groups 3 and 4, Group 3 had faster cleared.
Abstract: Monodisperse Fe particles tagged with /sup 198/Au were inhaled by 4 groups divided as: (1) 8 normal nonsmokers, (2) 8 smokers with mild bronchitis, (3) 12 bronchitics, and (4) 12 with bronchitis-bronchiectasis. External monitoring of deposition and clearance was accomplished with a scintillation detector. Mainly central deposition was found with large particles, rapid air flow, or shallow breathing. With opposite conditions, deposition was diffuse. Standard breathing with 2.04-..mu..m MMD particles produced central deposition at severe airway resistance (Groups 3, 4) in contrast to diffuse deposition in Groups 1 and 2. Less deposition was noted in areas of saccular bronchiectasis. Clearance was faster when deposition was central. However, between the first two groups, Group 1 had faster clearance; between Groups 3 and 4, Group 3 had faster clearance. Site of deposition may influence defense capabilities. Clearance speed may affect progress of bronchial disease.
TL;DR: The results of the measurements show that during the summer of 1967 the 238Pu activi show that following the arrival to the ground of the SNAP-9A 238PU fallout.
Abstract: Plutonium determinations have been carried out monthly on air filter samples (1966 and 1967) and on deposition samples (1967) with the aim of following the arrival to the ground of the SNAP-9A 238Pu fallout. The results of the measurements show that during the summer of 1967 the 238Pu activi
TL;DR: Leioclema asperum (Hall), a typical trepostomatous bryozoan, shows well developed acanthopores which are modified parts of orthodox zooecial walls and not separate skeletal entities, suggesting that deposition of calcite in that situation was virtually continuous.
Abstract: Leioclema asperum (Hall), a typical trepostomatous bryozoan, shows well developed acanthopores which are modified parts of orthodox zooecial walls and not separate skeletal entities. They resulted from locally accelerated forward growth of the wall, hence their distinctive cone-in-cone structure. The comparative absence of growth lines in the axial region of each acanthopore suggests that deposition of calcite in that situation was virtually continuous. There is no reason to believe that the acanthopores were originally hollow and they cannot have housed kenozooids, as is commonly supposed.
TL;DR: In this article, ground quartz, pretreated with HF, was shaken with buffer of pH 7·7 at 25°C, with and without added monosilicic acid.
Patent•
IBM1
TL;DR: In this article, the authors minimized autodoping during epitaxial deposition by sputtering a primary or initial film on a doped semiconductor substrate prior to the insertion of the epoxy.
Abstract: Autodoping is minimized during epitaxial deposition by sputtering a primary or initial film on a doped semiconductor substrate prior to epitaxial deposition.
01 Jan 1969
TL;DR: In this article, the formation of either micro-crystalline aggregates of β-rhombohedral boron or of a mixture of the β-rho-boron with small single crystals of tetragonal borons was observed.
Abstract: Abstract The deposition, on boron substrates, of boron obtained by reduction of boron trichloride with hydrogen was studied in the temperature range 1300°–1800°C. Under the conditions applied, the formation of either microcrystalline aggregates of β-rhombohedral boron or of a mixture of the β-rhombohedral boron with small single crystals of tetragonal boron was observed. It was found that the formation of tetragonal boron is restricted by the rate of boron deposition. The tetragonal modification was not formed at these rates above certain limits and these were different for various temperatures of the studied temperature range. The possible effects of impurities on the formation of the tetragonal modification of boron are discussed.
01 Sep 1969
TL;DR: A correlation was found between the amount and pattern of fat utilization or deposition and the reproductive condition of individuals.
Abstract: Specimens of Rana pipiens were subjected to different environmental conditions in order to determine the role of light and temperature on the amount and pattern of fat utilization, as well as the effects of these factors on the reproductive condition of the species. Temperature influences the amount of fat utilization; however, both light and temperature influence the pattern of fat utilization and the reproductive condition. A correlation was found between the amount and pattern of fat utilization or deposition and the reproductive condition of individuals.
01 Sep 1969
TL;DR: In this paper, the uniformity after the drive-in is predominantly dependent on the process variables during the deposition process, such as the design of the deposition system, the total carrier gas velocity, the spacing of wafers on a deposition boat and the reaction rate between BBr 3 and O 2, which is the most influential factor in determining the uniformness of diffusion.
Abstract: The variables affecting the uniformity of sheet resistance in a two step base diffusion system (deposition and drive-in), using BBr 3 as a source, have been investigated. The uniformity after the drive-in is predominantly dependent on the process variables during the deposition process. Amongst such variables as the design of the deposition system, the total carrier gas velocity, the spacing of wafers on a deposition boat and the reaction rate between BBr 3 and O 2 , the latter is the most influential factor in determining the uniformity of diffusion. A uniform diffusion along a certain length of the zone is obtained when the reaction rate between BBr 3 and O 2 has reached completion. This is indicated by the lowest sheet resistance (highest surface concentration) obtained and the highest amount of glass built up on the surface of silicon for a given deposition condition. The rate of reaction can be varied by varying the O 2 concentration or the temperature of reaction (or deposition). Increasing these variables causes an enhanced reaction rate thus shifting the position of the zone of uniform sheet resistance towards the gas inlet of the tube. Decreasing these variables has the reverse effect.
TL;DR: Cotton celluloses selected for pronounced differences in crystallinities and accessibilities have been cross-linked by the vapor-phase deposition of formaldehyde under conditions previously shown t... as mentioned in this paper.
Abstract: Cotton celluloses selected for pronounced differences in crystallinities and accessibilities have been cross-linked by the vapor-phase deposition of formaldehyde under conditions previously shown t...
01 Jan 1969
TL;DR: This Dissertation is brought to you for free and open access by the Theses and Dissertations at Loyola eCommons and expresses sincere appreciation to all those who have aided in making this investigation possible.