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1.
Certain low grade phosphate rocks have low agronomic value as direct applied fertilizers and make poor quality superphosphates. With some rocks there is potential to increase their solubility in soils and hence the fertilizer value by mixing with finely divided elemental sulphur (S°). The agronomic value of a prototype low cost, granular P and S fertilizer, Christmas Island Grade C phosphate rock/elemental sulphur (Xmas C/S°), was compared against single superphosphate (SSP) and reactive phosphate rock (RPR)/S° dry blends, North Carolina phosphate rock/S° (NCPR/S°) and NCPR/50% S-super (granular SSP + 44% S°). An eight- month glasshouse trial using ryegrass (Lolium perenne L. cv. Nui), grown in a central yellow-grey earth (Aeric Fragiaqualf), indicated that fertilization with Xmas C/S° produced dry matter yields, between 54 to 73% and 10 to 40% lower than SSP and NCPR/S° blends respectively, and lower plant P and S uptake. Fertilization with Xmas C/S° however produced significantly higher yield and P and S uptake than unfertilized pots and pots receiving Xmas C PR and S° alone. The two RPR/S° dry blends, namely NCPR/S° and NCPR/50% S-super, produced significantly lower yield and P and S uptake than the same two fertilizers granulated with water. The difference in yields and P and S uptake between blends and granulated forms increased with time. The recovery of fertilizer P and S by plants ranged from 3 to 35% and 2 to 45% respectively with the lowest recoveries for Xmas C PR alone and S° alone and the highest for SSP and SSP + S°. During the period of plant growth the percentage of S° oxidised from the S°, Xmas C/S° co-granule, NCPR/S° physical blend and NCPR/S° granular treatments were 37, 32, 32 and 45% respectively. Field evaluations, or use, of the co-granule should consider it's slow P and S release rates. 相似文献
2.
Observed 72 infants aged 12, 18, and 24 mo in the presence of their mothers and 2 adult female strangers to assess their willingness to initiate proximal interaction (PI) with unfamiliar adults. Mothers and strangers were asked to be warmly responsive to infant overtures but not to invite interaction from the infant. A majority of the infants at the 3 ages initiated PI with one or both strangers, often repeatedly. For those who engaged in 2 or more PI bouts with the strangers, a significant upward trend in bout duration and intensity was noted. Older infants gave more toys to the strangers and initiated more mutual play. Stranger–mother distance affected amount of proximity, not PI. Mother–stranger conversation was associated with less PI with the conversing stranger. At all ages infants sought more PI with their mothers than with the strangers. Although infants initiated an appreciable amount of PI with the strangers during the 40-min observation, comparison with other studies indicates that a stranger who takes the initiative by inviting play can establish more rapport much sooner. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
Carolyn Moorlag Quanzu Yang Tom Troczynski Jeremy Bretherton Colin Fyfe 《Journal of the American Ceramic Society》2004,87(11):2064-2071
Aluminum phosphate products formed by the reactions of alumina and alumina-gel systems with acidic phosphates were analyzed. Drying of alumina-gel to form microcrystalline boehmite and conversion to γ-alumina by thermal treatment was indicated by the appearance of octahedral, pentacoordinate, or tetrahedral sites, which were established using 27 Al magic-angle-spinning solid-state nuclear magnetic resonance spectroscopy. Crystalline aluminum phosphate products and amorphous material were identified using this technique. α-alumina and heat-treated alumina-gel that were reacted with phosphate in an Al:P ratio of 1:1 yielded dramatically different aluminum orthophosphate:aluminum metaphosphate product ratios of 8.2:1 and 1:1.1, respectively. When alumina-gel was heat-treated with phosphate, an abundance of aluminum orthophosphate, aluminum metaphosphate, and hydrated aluminum phosphate products were affected by varying conditions of temperature and time of heat treatment and by the amount of phosphate present. An α-alumina/alumina-gel composite sol–gel phase that was reacted with phosphoric acid (H3 PO4 ) in a Al:P ratio of 1:1 exhibited an increased quantity of aluminum metaphosphate products compared with an α-alumina:H3 PO4 ratio of 1:1 and a higher percentage of reaction (79%) compared with the reactions of an α-alumina:H3 PO4 ratio of 1:1 or an alumina-gel:H3 PO4 ratio of 1:1. The morphologies of aluminum triphosphate hydrate and aluminum metaphosphate product phases were observed using scanning electron microscopy. 相似文献
4.
Hypothesized that a rudimentary capacity to impute internal states to self and to other emerges with the onset of communicative intentions. The ability to speak about mental states begins late in the 2nd yr and burgeons in the 3rd yr. Mothers of 30 28-mo-olds were asked to report child utterances containing 6 categories of internal-state words (perception, physiology, affect, volition/ability, cognition, and moral judgment/obligation). Of these, affect, cognition, and moral terms were less common than the others. Ss who applied a specific label to self and other tended to use it also to speak about nonpresent states. Use of a term for only self was more common than use for only other. Causal statements referred primarily to affect. Three categories of causal statements were identified: state change/maintenance, antecedents of states, and definitions of states in terms of other states, physical symptoms, and behaviors. Assessments of internal-state language that were obtained through maternal observation/report and directly from the child were highly correlated. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
The development of children's verbal communication about feeling states was studied by analyzing naturally occurring conversations at home. The data were recorded during two longitudinal studies. In Study 1, 43 second-born children were observed with mother and older sibling at 18 and 24 months. In Study 2, 16 firstborn children were observed with mother and younger sibling at 25 and 32 months. Both studies showed that by 2 years of age, the majority of children referred to a range of feeling states in self and other, and they discussed the cause of feeling states in a variety of contexts (including pretend games). References to feeling states made by mother and older sibling when the target child was 18 months were positively correlated with the target child's speech about feeling states at 24 months. Both mothers and older siblings mentioned feeling states more frequently to girls than to boys. By 24 months, the girls themselves referred to feeling states significantly more often than boys. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
P. Loganathan M.J. Hedley M.R. Bretherton J.S. Rowarth 《Nutrient Cycling in Agroecosystems》2004,70(1):77-84
When fine particulate, slow-release fertilizers are applied to pastures, earthworm activity can physically move the particles both horizontally and vertically in the soil. This physical movement needs to be accounted for when researchers attempt to determine the rate of fertilizer dissolution by measuring the quantity of undissolved fertilizer residue remaining in the soil. A hard igneous phosphate rock (Phalaborwa PR) and an inert chromite ore were used as tracers to follow the physical movement of the reactive PR (RPR), NCPR applied to grazed pasture on a Pallic Soil (Aeric Fragiaqualf) isolated in galvanised steel cylindrical cores (150 mm diameter and 100 mm height) with or without nylon mesh sleeve (63 µm) at the bottom. The soil cores were sampled after 113, 270 and 559 days and analysed for PR and chromite residues. Results from both tracers showed that there was a significant movement of particles laterally out of the cores and vertically below 40 mm soil depth. Phalaborwa PR particle movement to 40–60 mm soil depth was 8% in 112 days and 24% in 270 days. Between 270 and 559 days no significant movement of particles was observed. Particle movement appeared to occur in discrete non-continuous events that were associated with the major end-of-autumn peaks in earthworm activity. When corrected for particle movement, the measured rate of NCPR dissolution satisfactorily fitted the rate of dissolution predicted by two models of PR dissolution. 相似文献
7.
Inge Bretherton; Elizabeth Bates; Sandra McNew; Cecilia Shore; Carol Williamson; Marjorie Beeghly-Smith 《Canadian Metallurgical Quarterly》1981,17(6):728
There is now considerable evidence in support of the Piagetian-Wernerian hypothesis that early language emerges out of a more general symbolic capacity, one that also includes the use of gestural symbolic schemes in play. The present study examined the same hypothesis, but in a situation with more controls over the eliciting conditions for different aspects of early symbolization. The processes studied were word comprehension, word production, and gestural production. Ss were 26 infants tested longitudinally at 13 and 20 mo, responding to the same set of familar objects in realistic vs abstract versions. Word comprehension was unaffected by the abstraction manipulation at either age, but did increase significantly over time. Word production also increased developmentally and interacted significantly with abstraction (with more naming of realistic objects). Gestural production actually decreased over time. The abstractness effect on gesture interacted with age, in that the difference between realistic and abstract objects was much greater at 13 mo. Results are discussed in terms of a "switchover" in the preferred modality for recognizing or categorizing objects in the 2nd yr. Differences in the contextual dependence of gesture and word (i.e., effect of perceptual detail in the object) are also considered. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
I. D. Sanches M. P. Tuohy M. J. Hedley M. R. Bretherton 《International journal of remote sensing》2013,34(9):2309-2319
The development of the Canopy Pasture Probe (CAPP), for acquisition of in situ pasture canopy reflectance factor, required a suitable large reflectance standard. Spectralon® has been successfully used worldwide as a reflectance standard, but large panels (greater than 20 cm diameter) suitable for use with the CAPP are very expensive. In this context, a large, durable and low cost reflectance standard has been evaluated for use with an Analytical Spectral Devices FieldSpec® Pro FR spectroradiometer attached to the CAPP. In this study various ceramic tiles, barium sulphate powders, white paint and a Kodak card were tested. The material which best suited the requirements for a reflectance standard was the white ceramic tile sourced from Argentina. This tile produced around 80% total reflectance with reasonable uniformity over the spectral range analysed (400–2400 nm); and the vegetation spectra acquired using this tile as reference sample were very similar in shape to the vegetation spectra acquired using spectralon® as a white reference. 相似文献
9.
Apparatus of the Faraday type to measure crystal magnetic susceptibilities is described in conjunction with the method of analysis to deduce the anisotropic molecular magnetic susceptibilities. The relative merits of the Faraday and torsion methods to measure anisotropic susceptibilities are discussed. The principal molecular susceptibilities* which were determined at 293 K for the cesium, potassium, and ammonium copper Tutton's salts indicate orthorhombic distortion in the crystal fields around the copper ion. 相似文献
10.
Memorializes Mary D. S. Ainsworth, one of the preeminent developmental psychologists of the 20th century. Her conceptual and empirical contributions to attachment theory have led to groundbreaking changes in how psychologists think about the connection between an infant and its caregivers and, by extension, about close human relationships at all ages. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献