999 resultados para GEMINI SPECTROSCOPIC SURVEY


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This paper reports findings from an empirical study examining the influence of student background and educational experiences on the development of career choice capability. Secondary school students attending years 9-12 (N = 706) in New South Wales, Australia, were invited to participate in an online survey that sought to examine factors influencing their readiness to make career choice. The survey included questions relating to student demographics, parental occupation, attitudes to school and to learning, career aspirations, and students’ knowledge of the further education or skills required to achieve their desired goal. We found no significant differences in the proportions of students who were ‘uncertain’ of their future career aspirations with respect to their individual characteristics such as age and gender. There were, however, significant differences in relation to students’ family background, and their perceptions associated with own academic abilities and self-efficacy.

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This paper is based on a study examining the impact of young people’s backgrounds and educational experiences on career choice capability with the aim of informing education policy. A total of 706 students from secondary schools (Years 9-12) in New South Wales, Australia took part in an online survey. This paper focuses on the differences found between groups on the basis of their educational experiences. Participants who were uncertain of their future career plans were more likely to attend non-selective, non-metropolitan schools and were more likely to hold negative attitudes towards school. Career ‘uncertain’ students were also less likely to be satisfied with the elective subjects offered at their school and reported less access to career education sessions. It is concluded that timely career information and guidance should be provided to students and their families in order to allow them to more meaningfully make use of the resources and opportunities available to them with a view toward converting these into real world benefits.

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The mineral fraipontite has been studied by using a combination of scanning electron microscopy with energy dispersive analysis and vibrational spectroscopy (infrared and Raman). Fraipontite is a member of the 1:1 clay minerals of the kaolinite-serpentine group. The mineral contains Zn and Cu and is of formula (Cu,Zn,Al)3(Si,Al)2O5(OH)4. Qualitative chemical analysis of fraipontite shows an aluminium silicate mineral with amounts of Cu and Zn. This kaolinite type mineral has been characterised by Raman and infrared spectroscopy; in this way aspects about the molecular structure of fraipontite clay are elucidated.

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The mineral chloritoid collected from the argillite in the bottom of Yaopo Formation of Western Beijing was characterized by mid-infrared (MIR) and near-infrared (NIR) spectroscopy. The MIR spectra showed all fundamental vibrations including the hydroxyl units, basic aluminosilicate framework and the influence of iron on the chloritoid structure. The NIR spectrum of the chloritoid showed combination (ν + δ)OH bands with the fundamental stretching (ν) and bending (δ) vibrations. Based on the chemical component data and the analysis result from the MIR and NIR spectra, the crystal structure of chloritoid from western hills of Beijing, China, can be illustrated. Therefore, the application of the technique across the entire infrared region is expected to become more routine and extend its usefulness, and the reproducibility of measurement and richness of qualitative information should be simultaneously considered for proper selection of a spectroscopic method for the unit cell structural analysis.

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The minerals clinotyrolite and fuxiaotuite are discredited in terms of the mineral tangdanite. The mixed anion mineral tangdanite Ca2Cu9(AsO4)4(SO4)0.5(OH)9 9H2O has been studied using a combination of Raman and infrared spectroscopy. Characteristic bands associated with arsenate, sulphate and hydroxyl units are identified. Broad bands in the OH stretching region are observed and are resolved into component bands. These bands are assigned to water and hydroxyl stretching vibrations. Two intense Raman bands at 837 and approximately 734 cm−1 are assigned to the ν1 (AsO4)3− symmetric stretching and ν3 (AsO4)3− antisymmetric stretching modes. Infrared bands at 1023 cm−1 are assigned to the (SO4)2− ν1 symmetric stretching mode, and infrared bands at 1052, 1110 and 1132 cm−1 assigned to (SO4)2− ν3 antisymmetric stretching modes, confirming the presence of the sulphate anion in the tangdanite structure. Raman bands at 593 and 628 cm−1 are attributed to the (SO4)2− ν4 bending modes. Low-intensity Raman bands found at 457 and 472 cm−1 are assigned to the (AsO4)3− ν2 bending modes. A comparison is made with the previously obtained spectral data on the discredited mineral clinotyrolite.

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The mineral aerinite is an interesting mineral because it contains both silicate and carbonate units which is unusual. It is also a highly colored mineral being bright blue/purple. We have studied aerinite using a combination of techniques which included scanning electron microscopy, energy dispersive X-ray analysis, Raman and infrared spectroscopy. Raman bands at 1049 and 1072 cm−1 are assigned to the carbonate symmetric stretching mode. This observation supports the concept of the non-equivalence of the carbonate units in the structure of aerinite. Multiple infrared bands at 1354, 1390 and 1450 cm−1 supports this concept. Raman bands at 933 and 974 cm−1 are assigned to silicon–oxygen stretching vibrations. Multiple hydroxyl stretching and bending vibrations show that water is in different molecular environments in the aerinite structure.

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We have studied the phosphate mineral vantasselite Al4(PO4)3(OH)3·9H2O using a combination of SEM with EDX and Raman and infrared spectroscopy. Qualitative chemical analysis shows Al, Fe and P. Raman bands at 1013 and 1027cm−1 are assigned to the PO43−ν1 symmetric stretching mode. The observation of two bands suggests the non-equivalence of the phosphate units in the vantasselite structure. Raman bands at 1051, 1076 and 1090cm−1 are attributed to the PO43−ν3 antisymmetric stretching vibration. A comparison is made with the spectroscopy of wardite. Strong infrared bands at 1044, 1078, 1092, 1112, 1133, 1180 and 1210cm−1 are attributed to the PO43−ν3 antisymmetric stretching mode. Some of these bands may be due to δAl2OH deformation modes. Vibrational spectroscopy offers a mechanism for the study of the molecular structure of vantasselite.

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The mineral brianyoungite, a carbonate–sulphate of zinc, has been studied by scanning electron microscopy (SEM) with chemical analysis using energy dispersive spectroscopy (EDX) and Raman and infrared spectroscopy. Multiple carbonate stretching modes are observed and support the concept of non-equivalent carbonate units in the brianyoungite structure. Intense Raman band at 1056 cm−1 with shoulder band at 1038 cm−1 is assigned to the CO32− ν1 symmetric stretching mode. Two intense Raman bands at 973 and 984 cm−1 are assigned to the symmetric stretching modes of the SO42− anion. The observation of two bands supports the concept of the non-equivalence of sulphate units in the brianyoungite structure. Raman bands at 704 and 736 cm−1 are assigned to the CO32− ν4 bending modes and Raman bands at 507, 528, 609 and 638 cm−1 are assigned to the CO32− ν2 bending modes. Multiple Raman and infrared bands in the OH stretching region are observed, proving the existence of water and hydroxyl units in different molecular environments in the structure of brianyoungite. Vibrational spectroscopy enhances our knowledge of the molecular structure of brianyoungite.

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The mineral aluminite has been studied using a number of techniques, including scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDX) and Raman and infrared spectroscopy. Raman spectroscopy identifies multiple sulphate symmetric stretching modes in line with the three sulphate crystallographically different sites. Raman spectroscopy also identifies a low intensity band at 1069 cm−1 which may be attributed to a carbonate symmetric stretching mode, indicating the presence of thaumasite. The observation of multiple bands in this ν4 spectral region offers evidence for the reduction in symmetry of the sulphate anion from Td to C2v or even lower symmetry. The Raman band at 3588 cm−1 is assigned to the OH unit stretching vibration and the broad feature at around 3439 cm−1 to water stretching bands. Water stretching vibrations are observed at 3157, 3294, 3378 and 3439 cm−1. Vibrational spectroscopy enables an assessment of the molecular structure of aluminite to be made.

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The mineral tilleyite-Y, a carbonate-silicate of calcium, has been studied by scanning electron microscopy with chemical analysis using energy dispersive spectroscopy (EDX) and Raman and infrared spectroscopy. Multiple carbonate stretching modes are observed and support the concept of non-equivalent carbonate units in the tilleyite structure. Multiple Raman and infrared bands in the OH stretching region are observed, proving the existence of water in different molecular environments in the structure of tilleyite. Vibrational spectroscopy offers new information on the mineral tilleyite.

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We have undertaken a study of the tellurite mineral sonorite using electron microscopy with EDX combined with vibrational spectroscopy. Chemical analysis shows a homogeneous composition, with predominance of Te, Fe, Ce and In with minor amounts of S. Raman spectroscopy has been used to study the mineral sonoraite an examples of group A(XO3), with hydroxyl and water units in the mineral structure. The free tellurite ion has C3v symmetry and four modes, 2A1 and 2E. An intense Raman band at 734 cm−1 is assigned to the ν1 (TeO3)2− symmetric stretching mode. A band at 636 cm−1 is assigned to the ν3 (TeO3)2− antisymmetric stretching mode. Bands at 350 and 373 cm−1 and the two bands at 425 and 438 cm−1 are assigned to the (TeO3)2−ν2 (A1) bending mode and (TeO3)2−ν4 (E) bending modes. The sharp band at 3283 cm−1 assigned to the OH stretching vibration of the OH units is superimposed upon a broader spectral profile with Raman bands at 3215, 3302, 3349 and 3415 cm−1 are attributed to water stretching bands. The techniques of Raman and infrared spectroscopy are excellent for the study of tellurite minerals.

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Raman and infrared spectra of three well-defined turquoise samples, CuAl6(PO4)4(OH)8·4H2O, from Lavender Pit, Bisbee, Cochise county, Arizona; Kouroudaiko mine, Faleme river, Senegal and Lynch Station, Virginia were studied, interpreted and compared. Observed Raman and infrared bands were assigned to the stretching and bending vibrations of phosphate tetrahedra, water molecules and hydroxyl ions. Approximate O–H⋯O hydrogen bond lengths were inferred from the Raman and infrared spectra. No Raman and infrared bands attributable to the stretching and bending vibrations of (PO3OH)2− units were observed.

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Background: To effectively care for people who are terminally ill, including those without decision-making capacity, palliative care physicians must know and understand the legal standing of Advance Care Planning (ACP) in their jurisdiction of practice. This includes the use of advance directives/living wills (ADs) and substitute decision-makers (SDMs) who can legally consent to or refuse treatment if there is no valid AD. Aim: The study aimed to investigate the knowledge, attitudes and practices of medical specialists most often involved in end-of-life care in relation to the law on withholding/ withdrawing life-sustaining treatment (WWLST) from adults without decision-making capacity. Design/participants: A pre-piloted survey was posted to specialists in palliative, emergency, geriatric, renal and respiratory medicine, intensive care and medical oncology in three Australian States. Surveys were analysed using SPSS20 and SAS 9.3. Results: The overall response rate was 32% (867/2702); 52% from palliative care specialists. Palliative Care specialists and Geriatricians had significantly more positive attitudes towards the law (χ242 = 94.352; p < 0.001) and higher levels of knowledge about the WWLST law (χ27 = 30.033; p < 0.001), than did the other specialists, while still having critical gaps in their knowledge. Conclusions: A high level of knowledge of the law is essential to ensure that patients’ wishes and decisions, expressed through ACP, are respected to the maximum extent possible within the law, thereby according with the principles and philosophy of palliative care. It is also essential to protect health professionals from legal action resulting from unauthorised provision or removal of treatment.

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The mineral lamprophyllite is fundamentally a silicate based upon tetrahedral siloxane units with extensive substitution in the formula. Lamprophyllite is a complex group of sorosilicates with general chemical formula given as A2B4C2Si2O7(X)4, where the site A can be occupied by strontium, barium, sodium, and potassium; the B site is occupied by sodium, titanium, iron, manganese, magnesium, and calcium. The site C is mainly occupied by titanium or ferric iron and X includes the anions fluoride, hydroxyl, and oxide. Chemical composition shows a homogeneous phase, composed of Si, Na, Ti, and Fe. This complexity of formula is reflected in the complexity of both the Raman and infrared spectra. The Raman spectrum is characterized by intense bands at 918 and 940 cm−1. Other intense Raman bands are found at 576, 671, and 707 cm−1. These bands are assigned to the stretching and bending modes of the tetrahedral siloxane units.

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We have studied the mineral kaliborite. The sample originated from the Inder B deposit, Atyrau Province, Kazakhstan, and is part of the collection of the Geology Department of the Federal University of Ouro Preto, Minas Gerais, Brazil. The mineral is characterized by a single intense Raman band at 756 cm−1 assigned to the symmetric stretching modes of trigonal boron. Raman bands at 1229 and 1309 cm−1 are assigned to hydroxyl in-plane bending modes of boron hydroxyl units. Raman bands are resolved at 2929, 3041, 3133, 3172, 3202, 3245, 3336, 3398, and 3517 cm−1. These Raman bands are assigned to water stretching vibrations. A very intense sharp Raman band at 3597 cm−1 with a shoulder band at 3590 cm−1 is assigned to the stretching vibration of the hydroxyl units. The Raman data are complimented with infrared data and compared with the spectrum of kaliborite downloaded from the Arizona State University database. Differences are noted between the spectrum obtained in this work and that from the Arizona State University database. This research shows that minerals stored in a museum mineral collection age with time. Vibrational spectroscopy enhances our knowledge of the molecular structure of kaliborite.