Resistance of Refractories to Molten Lead-Bismuth Alloy

In conjunction with studies of the suitability of liquid metals for high-temperature heat-transfer systems, an investigation was made to determine the resistance of forty materials–eighteen ceramics and cermets, thirteen refractory metals, and nine high-temperature alloys–to attack by Pb-Bi eutectic alloy (44.5% Pb and 55.5% Bi) in a dynamic system at temperatures of 1500° or 2000°F. The experimental apparatus and procedure is described. With the exception of ZrC all the ceramics and cermets were resistant to attack by molten Pb-Bi eutectic at 2000°F. Of the thirteen refractory metals only arc-cast molybdenum exhibited resistance to Pb-Bi at 2000°F. All nine of the high-temperature alloys had poor resistance at 1500°F.     

TREATMENT OF A RECURRENT NIGHTMARE BY BEHAVIOR-MODIFICATION PROCEDURES: A CASE STUDY.

THE TREATMENT OF A CASE OF A RECURRENT NIGHTMARE THAT WAS APPARENTLY SUCCESSFULLY TREATED BY BEHAVIOR-MODIFICATION PROCEDURES IS REPORTED. THE CLIENT REPORTED HAVING THE SAME DREAM 3-5 TIMES A WK. FOR APPROXIMATELY 15 YR. A VARIANT OF WOLPE'S SYSTEMATIC DESENSITIZATION WAS USED IN AN ATTEMPT TO REDUCE THE ANXIETY ELICITED BY THE DREAM. THE CLIENT REPORTED THAT THE DREAM DISAPPEARED, AND THERAPY WAS TERMINATED AFTER A TOTAL OF 13 CONTACTS. BOTH A 3-WK AND A 6-MO FOLLOW-UP REVEALED NO RECURRENCE OF THE DREAM NOR ANY EVIDENCE OF ANY FORM OF SYMPTOM SUBSTITUTION. A DISCUSSION OF THEORETICAL ISSUES IS INCLUDED. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Lactose Crystallization from Whey Permeate in an Ethanol-Water Mixture

A 30% concentrated permeate of a whey ultrafiltration process was used for producing crystalline a-lactose monohydrate. Effect of pH (2.75–5.5 pH units) at solvent to solute ratio 10:1 v/w, agitation and seeding (0.004–0.02%) on rate of lactose crystallization were examined. Conditions which were favorable in terms of crystallized lactose yield, and time of crystallization were: pH 5.5, agitation with or without seeding and 22°C. The first-order reaction-rate constant for crystallization ranged from 0.0178 to 0.200 hr^?1 depending on conditions.     

Hot-Pressing of Silicon Carbide with 1% Boron Carbide Addition

The densification behavior of pressure sintered cubic silicon carbide containing 1 wt% boron carbide was studied as a function of temperature (1750° to 1950°C). Specimens of theoretical density were obtained at 1950° with a pressure of 3000 psi. Experimental results showed that densification proceeded by a plastic flow mechanism. Interpretation of the data in terms of Murray's equation yields an activation energy of (11S ± 18) kcal/mol. At 1850C and above, tabular grains of 6H and 2H SiC were observed in a matrix of fine grains of 3C SiC.     

FUTURE TIME PERSPECTIVE: ITS RELATION TO THE SOCIALIZATION PROCESS AND THE DELINQUENT ROLE.

USED THE ASSUMPTION THAT PERSONAL FUTURE TIME PERSPECTIVE (FTP) IS RELATED TO THE OUTCOME OF THE SOCIALIZATION PROCESS TO TEST THE HYPOTHESIS THAT NONDELINQUENT (ND) AND DELINQUENT (D) BOYS WOULD BE SIGNIFICANTLY DIFFERENT IN THE EXTENT OF FTP. 100 NDS AND 100 DS MATCHED FOR AGE, SOCIAL STATUS, RACE, AND INTELLIGENCE WERE ADMINISTERED THE FUTURE EVENTS TEST. THE NDS ACHIEVED A SIGNIFICANTLY GREATER EXTENT OF FTP THAN THE DS. RESULTS WERE REPLICATED ON A RANDOM SAMPLE OF 100 NDS AND 100 DS. THE RESULTS WERE ALMOST IDENTICAL TO THOSE FOUND IN THE MATCHED GROUPS. AN ANALYSIS OF THE 36 TEST ITEMS REVEALED THOSE ITEMS WITH (1) DIFFERENTIAL ENDORSEMENT BETWEEN ND AND D SAMPLES, (2) SIGNIFICANTLY DIFFERENT MEAN FUTURE AGE SCORES BETWEEN GROUPS, AND (3) DIFFERENTIAL VARIABILITY BETWEEN THE NDS AND DS. GENERALLY THE NDS ENDORSED THE MORE PROSOCIAL ITEMS, WERE MORE HOMOGENEOUS IN FTP SCORES, AND WERE MORE REALITY ORIENTED WITH REGARD TO THE FUTURE. (21 REF.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of Melting History on the Mechanical Properties of Glass: I, Role of Melting Time and Atmosphere

The pristine strength of 0.5Li₂O·0.5K₂O·2SiO₂ glass measured in 3-point bending under liquid nitrogen was studied as a function of melting time and atmosphere at a constant melting temperature. The atmosphere over the melt was one of the most important parameters affecting the pristine strength. The most significant time-dependent melting effects and the highest strengths resulted from melting in a dry atmosphere of O₂ or air. In contrast, vacuum-melted and Ar-melted glasses had the lowest strengths. Melting in N₂ or CO₂ led to intermediate strengths. The presence of water vapor in the atmosphere during melting was detrimental to strength in those cases where very high strengths had been obtained with dry gases. The introduction of water vapor into those gases which in the dry state had led to low-strength glasses did not significantly affect the strength. The effects of the atmosphere in leading to oxygen-deficient or excess-oxygen glasses on the formation or dissolution of microheterogeneous regions were correlated with the pristine strengths of the glasses.     

STUDIES ON MECHANISMS OF RETENTION OF VOLATILE IN FREEZE-DRIED FOOD MODELS: THE SYSTEM PVP-n-PROPANOL

Retention of C¹⁴-labeled n-propanol was studied in a freeze-dried system containing polyvinylpyrrolidone (PVP). Variables affecting retention during freeze drying were: initial concentrations of PVP and n-propanol, rate of freezing and sample thickness. Rehumidification above the BET monolayer value resulted in losses of propanol which increased with increasing water content. Behavior of the model system based on PVP is consistent with the "microregion volatile entrapment theory." The PVP system (and perhaps polymeric carbohydrates) differ from low molecular weight carbohydrates: water sorption below the BET monolayer is reduced by entrapped volatile, and absolute level of retention is lower     

MEDIATION EFFECTS AS A FUNCTION OF MEDIATOR RECALL AND MEANINGFULNESS.

STUDIED MEDIATION EFFECTS AS A FUNCTION OF MEDIATOR RECALL AND MEANINGFULNESS. USING THE A-B, A-C, B-C (A-B, D-C, B-C CONTROL) PARADIGM, B AND C ITEMS WERE PRESENTED AT A 0/6, 2/6, 4/6, OR 6/6 CRITERION OF STAGE 3 ACQUISITION, AND S RECALLED THE ITEMS ASSOCIATED WITH B AND C IN STAGES 1 AND 2. THE A AND D ITEMS WERE PRESENTED AFTER STAGE 2 IN ORDER TO ASSESS DIFFERENCES IN FORWARD AND BACKWARD RECALL AT THE 0/6 CRITERION. HIGH- AND LOW-M VERBAL MATERIAL CONDITIONS WERE ORTHOGONAL TO THE RECALL CONDITIONS. THE MAJOR RESULTS WERE: (1) HIGH-M MATERIALS APPARENTLY YIELD SUPERIOR BACKWARD LEARNING AND LESS BACKWARD UNLEARNING IN STAGES 1 AND 2, THUS MAKING THE MEDIATOR MORE AVAILABLE FOR HIGH-M MATERIAL AT THE ONSET OF STAGE 3; (2) STAGE 3 ACQUISITION PRODUCES A GENERAL DECREASE IN MEDIATOR RECALL; AND (3) THERE WAS A GENERAL LACK OF RELATIONSHIP BETWEEN MEDIATOR RECALL IN STAGE 3 AND B-C PERFORMANCE. THE FINDINGS WERE INTERPRETED IN TERMS OF THE RELATION OF ASSOCIATIVE STRENGTH OF B-A AND C-A AFTER STAGE 1 AND 2 ACQUISITION AND ITS RELATION TO MEDIATOR USAGE. (FRENCH SUMMARY) (19 REF.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)