scholarly journals The GALLEX Project

1990 ◽  
Vol 121 ◽  
pp. 187-199
Author(s):  
T. Kirsten ◽  
M. Breitenbach ◽  
W. Hampel ◽  
G. Heusser ◽  
J. Kiko ◽  
...  
Keyword(s):  
Present Status ◽  
Chloride Solution ◽  
Solar Neutrinos ◽  
Full Scale ◽  
Gallium Chloride

AbstractThe GALLEX collaboration aims at the detection of solar neutrinos in a radiochemical experiment employing 30 tons of Gallium in form of concentrated aqueous Gallium-chloride solution. The detector is primarily sensitive to the otherwise inaccessible pp-neutrinos. Details of the experiment have been repeatedly described before [1-7]. Here we report the present status of implementation in the Laboratori Nazionali del Gran Sasso (Italy). So far, 12.2 tons of Gallium are at hand. The present status of development allows to start the first full scale run at the time when 30 tons of Gallium become available. This date is expected to be January, 1990.

Direct Titrimetric Microdetermination of Fluorodifen, Linuron, Faneron, and Pebulate

1973 ◽  
Vol 56 (2) ◽  
pp. 387-389
Author(s):  
Syed L Abbas ◽  
Asoke K Ghosh ◽  
Saiyid A I Rizvi ◽  
Om C Saxena
Keyword(s):  
Chloride Solution ◽  
Gallium Chloride ◽  
Direct Titration ◽  
Standard Solutions

Abstract The herbicides fluorodifen, linuron, faneron, and pebulate have been determined in individual standard solutions by direct titration against gallium chloride solution, using different indicators. The same technique is applied to estimation of these herbicides in treated soils. The complex between gallium chloride and fluordifen or linuron is formed in a 1:3 ratio, whereas the complex with faneron or pebulate is in a 1:1 ratio. Recoveries for fluorodifen, linuron, faneron, and pebulate were 99.9–101.5, 99.0–102.4, 97.1–101.3, and 98.3–101.2%, respectively. Treatment with herbicide lowered the pH of the soil.

scholarly journals Matter Effects in Neutrino Propagation

1990 ◽  
Vol 121 ◽  
pp. 231-250
Author(s):  
A. Yu. Smirnov
Keyword(s):  
Present Status ◽  
Solar Neutrinos ◽  
Matter Density ◽  
The Sun ◽  
Matter Effects ◽  
Density Perturbations ◽  
Neutrino Propagation

AbstractConditions and dynamics of the resonant neutrino conversion are described. We discuss the applications of the effect to the solar neutrinos as well as present status of the conversion inside the Sun. The influence of different matter density perturbations on the conversion is considered, and in this connection the possible effects of parametric and stochastic enhancement of the influence are remarked.

scholarly journals Recovery of Gallium from Simulated GaAs Waste Etching Solutions by Solvent Extraction

2020 ◽  
Vol 12 (5) ◽  
pp. 1765 ◽  
Author(s):  
Wei-Sheng Chen ◽  
Ko-Wei Tien ◽  
Li-Pang Wang ◽  
Cheng-Han Lee ◽  
Yi-Fan Chung
Keyword(s):  
Chloride Solution ◽  
Extraction Efficiency ◽  
Ph Value ◽  
Iron Sulfate ◽  
Etching Solution ◽  
Arsenic Trisulfide ◽  
Gallium Chloride ◽  
Gaas Wafer ◽  
Extraction Step ◽  
Gallium Trichloride

Gallium arsenide is used in semiconductor industries worldwide. Numerous waste etching solutions are produced during the processes of GaAs wafer production. Therefore, a complete and eco-friendly technology should be established to recover gallium as a gallium chloride solution and remove arsenic ion from waste GaAs etching solution. In this study, the gallium trichloride and arsenic trisulfide powders were dissolved in ammonia solutions to prepare the simulated solutions, and the pH value was adjusted to pH 2 by nitric acid. In the extraction step, the GaAs etching solutions were extracted using 0.5 M Cyanex 272 solutions in kerosene at pH 2 and 0.1 O/A ratio for 5 min. The extraction efficiency attained 77.4%, which had an optimal ratio of concentration, and the four steps extraction efficiency attained 99.5%. After extraction, iron sulfate heptahydrates were added into the raffinate, and the arsenic ions were precipitated. The removed rate attained 99.9% when the Fe/As ratio was 10. In the stripping step, the organic phase was stripped with 0.5 M hydrochloric acid at 1 O/A ratio for 3 min, and 97.5% gallium was stripped. Finally, the purity of gallium chloride solution was 99.95% and the gallium was seven times the concentration of the etching solutions.

Present status of radio astrometry with baselines ≤ 35 km

1978 ◽  
Vol 48 ◽  
pp. 175-178 ◽  
Author(s):  
K. J. Johnston
Keyword(s):  
Present Status ◽  
Future Work

A summary of results for radio astrometry with baselines ≤ 35 km and priorities for future work are given.

Relation of Statistically Significant, Abnormal, and Typical WAIS-R VIQ-PIQ Discrepancies to Full Scale IQs

2000 ◽  
Vol 16 (2) ◽  
pp. 107-114 ◽  
Author(s):  
Louis M. Hsu ◽  
Judy Hayman ◽  
Judith Koch ◽  
Debbie Mandell
Keyword(s):  
Graphical Method ◽  
The United States ◽  
Full Scale ◽  
True Score ◽  
Absolute Value ◽  
Normative Population ◽  
The Us ◽  
The Mean ◽  
And Performance ◽  
Quadratic Models

Summary: In the United States' normative population for the WAIS-R, differences (Ds) between persons' verbal and performance IQs (VIQs and PIQs) tend to increase with an increase in full scale IQs (FSIQs). This suggests that norm-referenced interpretations of Ds should take FSIQs into account. Two new graphs are presented to facilitate this type of interpretation. One of these graphs estimates the mean of absolute values of D (called typical D) at each FSIQ level of the US normative population. The other graph estimates the absolute value of D that is exceeded only 5% of the time (called abnormal D) at each FSIQ level of this population. A graph for the identification of conventional “statistically significant Ds” (also called “reliable Ds”) is also presented. A reliable D is defined in the context of classical true score theory as an absolute D that is unlikely (p < .05) to be exceeded by a person whose true VIQ and PIQ are equal. As conventionally defined reliable Ds do not depend on the FSIQ. The graphs of typical and abnormal Ds are based on quadratic models of the relation of sizes of Ds to FSIQs. These models are generalizations of models described in Hsu (1996) . The new graphical method of identifying Abnormal Ds is compared to the conventional Payne-Jones method of identifying these Ds. Implications of the three juxtaposed graphs for the interpretation of VIQ-PIQ differences are discussed.

A Modification of the Payne-Jones Method of Identifying Abnormal Differences in WISC-R Performance and Verbal IQ's

1996 ◽  
Vol 12 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Louis M. Hsu
Keyword(s):  
Full Scale ◽  
True Score ◽  
Verbal Iq ◽  
Score Difference ◽  
The Difference ◽  
And Performance

The difference (D) between a person's Verbal IQ (VIQ) and Performance IQ (PIQ) has for some time been considered clinically meaningful ( Kaufman, 1976 , 1979 ; Matarazzo, 1990 , 1991 ; Matarazzo & Herman, 1985 ; Sattler, 1982 ; Wechsler, 1984 ). Particularly useful is information about the degree to which a difference (D) between scores is “abnormal” (i.e., deviant in a standardization group) as opposed to simply “reliable” (i.e., indicative of a true score difference) ( Mittenberg, Thompson, & Schwartz, 1991 ; Silverstein, 1981 ; Payne & Jones, 1957 ). Payne and Jones (1957) proposed a formula to identify “abnormal” differences, which has been used extensively in the literature, and which has generally yielded good approximations to empirically determined “abnormal” differences ( Silverstein, 1985 ; Matarazzo & Herman, 1985 ). However applications of this formula have not taken into account the dependence (demonstrated by Kaufman, 1976 , 1979 , and Matarazzo & Herman, 1985 ) of Ds on Full Scale IQs (FSIQs). This has led to overestimation of “abnormality” of Ds of high FSIQ children, and underestimation of “abnormality” of Ds of low FSIQ children. This article presents a formula for identification of abnormal WISC-R Ds, which overcomes these problems, by explicitly taking into account the dependence of Ds on FSIQs.

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