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Di-μ-oxido-bis-[(1,4,8,11-tetra-aza-cyclo-tetra-decane-κN,N',N'',N''')dimangan-ese(III,IV)] bis-(tetra-phenyl-borate) chloride acetonitrile disolvate.
The title compound, [Mn(2)O(2)(C(10)H(24)N(4))(2)](C(24)H(20)B)(2)Cl·2CH(3)CN, is a mixed-valent Mn(III)/Mn(IV) oxide-bridged mangan-ese dimer with one chloride and two tetra-phenyl-borate counter-anions. There are two non-coordinated mol-ecules of acetonitrile in the formula unit. A center of inversion is present between the two metal atoms, and, consequently, there is no distinction between Mn(III) and Mn(IV) metal centers. In the Mn(2)O(2) core, the Mn-O distances are 1.817 (3) and 1.821 (3) Å. The cyclam ligand is in the cis configuration. The chloride counter-anion resides on a center of symmetry, whereas the tetra-phenyl-borate counter-anion is in a general position. The cyclam ligand is hydrogen bonded to the acetonitrile as well as to the chloride anion. One of the phenyl rings of the anion and the acetonitrile solvent molecule are each disordered over two sets of sites
Growth Rates at Various temperatures of the Orange-Throat Darter Etheostoma spectabile (Agassiz)
School Phobia: A Review of Some Issues
It is now quite well established that children, usually said to be suffering from school phobia (Johnson et al, 1941). or school refusal (Morgan, 1959). have great difficulty in attending school as a result of a neurotic disturbance, and that this is quite distinct from truancy, which is more often part of an anti-social or conduct disorder (Warren, 1948; Hersov, 1960a). School phobia is a condition which involves more than a simple fear of school. Johnson et al (1941) claimed that the essential problem lay in an unresolved mutual dependency relationship between mother and child, with arousal of intense separation anxiety at the prospect of school attendance
Graduate Wind Instrument Recital
Since the end of World War II most teacher-training institutions have reinforced and expanded requirements for graduation in instrumental music education; but the problem still remains of determining the actual training needs of the instrumental music educator and the manner in which these needs can best be fulfilled in the relatively brief period of time available for educating the teacher . It is the responsibility of the music departments of the teacher-training institutions to determine the most practical and efficient courses and projects which will better equip students in instrumental music education for teaching general music classes, performing on their major instruments, conducting, organizing instrument al courses of study, selecting suit able music, arranging, etc
Physical Attractiveness - a Source of Teacher Bias?
A person\u27s physical appearance is his personal characteristic most obvious and most accessible to others in social interaction. Despite some social psychologists apparent disinterest in investigating physical attractiveness as an antecedent of liking, there has been a developing body of research which suggests that physical attractiveness is an important social cue used by others as a basis for social evaluation. If, as there appears, there is a physical attractiveness stereotype, it seems plausible to suggest that a child\u27s personal characteristics may influence the way in which an adult evaluates his behaviour. There have been several studies that have looked at this issue as it might affect the classroom situation. These studies suggest that teachers may hold differential expectations for attractive and unattractive children
Value Systems of Prospective Teachers
The teacher in the primary school classroom provides for the children in her care a variety of experiences in number, in the language arts, and in all the other concomitants of the formal curriculum of the school. But she also provides other experiences: a set of socializing experiences arising from her behaviour in the classroom. This includes the types of interpersonal relationships she has with the children, the demands she makes, the expectations she has of individuals and groups and the priorities she sets. In this context an examination of factors lying behind the behaviours the teacher exhibits in the classroom is important. One factor seen as being of major relevance is the teacher\u27s value system
A Graduate-Oriented Evaluation of the Music Education Curricula of Four State College-University Systems in Utah
The purpose of the study was to make an evaluation of curricula-training effectiveness, applicability, and need for additional training within four of the state-supported college-universities of Utah. The schools researched were Utah State University, the University of Utah, Weber State College, and Southern Utah State College. The descriptive research techniques of a closed-form questionnaire were utilized to obtain informational data for the years 1969-1971 from graduates, faculties, and selected graduates concerning common and traditional curricular areas of Ca) music theory, (b) scoring and arranging, (c) music history, Cd) conducting and rehearsal techniques, (e) vocal methods and materials, (f) instrumental methods and materials, (g) group instruction, (h) private instruction on the major instrument, (i) performance, and (j) minor instrument repair. The data revealed that there was no significant difference in the responses to the questionnaire across graduates, across faculties, across institutions, or across graduates and faculty from the same institution. The conclusions from the study indicated: present training effectiveness is generally excellent in all areas of the music education curricula in all four schools; training is highly applicable; although the training is excellent and applicable, there remains the strong desire by both graduates and faculty for additional training in all areas of curricula with the exception of traditional-music history
Library Economic Metrics: Examples of the Comparison of Electronic and Print Journal Collections and Collection Services
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The application of S isotopes and S/Se ratios in determining ore-forming processes of magmatic Ni–Cu–PGE sulfide deposits: a cautionary case study from the northern Bushveld Complex
The application of S/Se ratios and S isotopes in the study of magmatic Ni–Cu–PGE sulfide deposits has long been used to trace the source of S and to constrain the role of crustal contamination in triggering sulfide saturation. However, both S/Se ratios and S isotopes are subject to syn- and post-magmatic processes that may alter their initial signatures. We present in situ mineral δ34S signatures and S/Se ratios combined with bulk S/Se ratios to investigate and assess their utility in constraining ore-forming processes and the source of S within magmatic sulfide deposits.
Magmatic Ni–Cu–PGE sulfide mineralization in the Grasvally Norite–Pyroxenite–Anorthosite (GNPA) member, northern Bushveld Complex was used as a case study based on well-defined constraints of sulfide paragenesis and local S isotope signatures. A crustal δ34S component is evident in the most primary sulfide assemblage regardless of footwall lithology, and is inferred that the parental magma(s) of the GNPA member was crustally contaminated and sulfide saturated at the time of emplacement. However, S/Se ratios of both the primary and in particular secondary sulfide assemblages record values within or below the mantle range, rather than high crustal S/Se ratios. In addition, there is a wide range of S/Se ratio for each sulfide mineral within individual assemblages that is not necessarily consistent with the bulk ratio. The initial crustal S/Se ratio is interpreted to have been significantly modified by syn-magmatic lowering of S/Se ratio by sulfide dissolution, and post-magmatic lowering of the S/Se ratio from hydrothermal S-loss, which also increases the PGE tenor of the sulfides. Trace element signatures and variations in Th/Yb and Nb/Th ratios support both an early pre-emplacement contamination event as seen by the S isotopes and S/Se ratios, but also a second contamination event resulting from the interaction of the GNPA magma with the local footwall country rocks at the time of emplacement; though this did not add any additional S. We are able to present an integrated emplacement and contamination model for the northern limb of the Bushveld Complex.
Although the multitude of processes that affect variations in the δ34S signature and in particular S/Se ratio may be problematic in interpreting ore genesis, they can reveal a wealth of additional detail on a number of processes involved in the genetic history of a Ni–Cu–PGE deposit in addition to crustal contamination. However, a prerequisite for being able to do this is to utilize other independent petrological and mineralogical techniques that provide constraints on both the timing and effect of various ore-forming and modifying processes. Utilizing both bulk and in situ methods in concert to determine the S/Se ratio allows for the assessment of multiple sulfide populations, the partitioning behaviour of Se during sulfide liquid fractionation and also the effects of low temperature fluid alteration. In comparison, S isotopes are relatively more robust and represent a more reliable indicator of the role of crustal S contamination. The addition of trace element data to the above makes for an incredibly powerful approach in assessing the role of crustal contamination in magmatic sulfide systems
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