Raman Spectroscopic and SEM Analysis of Sodium-Zippeite

Raman at 298 and 77 K and infrared spectra of two samples of sodium-zippeite were studied and interpreted. U-O bond lengths in uranyl were calculated and compared with those inferred from the X-ray single crystal structure data of a synthetic sodium-zippeite analog. Hydrogen-bonding network in the studied samples is discussed. O-H…O bond lengths were calculated and compared with those predicted from the X-ray single crystal structure analysis

Raman Spectroscopy of the Sampleite Group of Minerals

Raman and infrared spectroscopy has enabled insights into the molecular structure of the sampleite group of minerals. These minerals are based upon the incorporation of either phosphate or arsenate with chloride anion into the structure and as a consequence the spectra refect the bands attributable to these anions, namely phosphate or arsenate with chloride. The sampleite vibrational spectrum reflects the spectrum of the phosphate anion and consists of ν1 at 964, ν2 at 451 cm-1, ν3 at 1016 and 1088 and ν4 at 643, 604, 591 and 557 cm-1. The lavendulan spectrum consists of ν1 at 854, ν2 at 345 cm-1, ν3 at 878 cm-1 and ν4 at 545 cm-1. The Raman spectrum of lemanskiite is different from that of lavendulan consistent with a different structure. Low wavenumber bands at 227 and 210 cm-1 may be assigned to CuCl TO/LO optic vibrations. Raman spectroscopy identified the substitution of arsenate by phosphate in zdenekite and lavendulan

Isomorphic Substitution in Vanadinite [Pb5(VO4)3C1] - Raman Spectroscopic Study

The Raman and infrared spectroscopy of three vanadinite [Pb5(VO4)Cl] specimens from three localities has been studied. Single crystal Raman spectra were obtained and the spectra were found to be both orientation and temperature dependent. Measurement of the Raman spectra at liquid nitrogen temperature enabled better band separation and increased intensities of weak bands through band narrowing enabling, the assignment of the bands in vanadinites to be made. Two types of isomorphous substitution are identified (a) substitution in the bulk of the crystal where electron beam microanalysis identifies the presence of calcium and copper. (b) surface substitution where infrared spectroscopy shows the isomorphous substitution of vanadate by phosphate and of chloride by hydroxyl groups

Count me in! Gender and ethnic minority attainment in school science

There is no single 'solution' to the 'problem' of under-achievement in school science by certain groups. Such under-achievement is strongly connected to the ways that society views the members of these groups. It is not enough for schools to be isolated islands of good practice; they need to help students critically reflect on the world inside and outside of school, and then equip students with the necessary tools to deal with this world. A number of strategies are suggested for use in schools to help pupils and students from groups which often underachieve to get more from their science lessons

Vibrational Spectroscopy of Selected Natural Uranyl Vanadates

Raman spectroscopy has been used to study a selection of uranyl vanadate minerals including carnotite, curienite, francevillite, tyuyamunite and metatyuyamunite. The minerals are characterised by an intense band in the 800 to 824 cm-1 region, assigned to the ν1 symmetric stretching vibrations of the (UO2)2+ units. A second intense band is observed in the 965 to 985 cm-1 range and is attributed to the ν1 (VO3) symmetric stretching vibrations in the (V2O8) units. This band is split with a second component observed at around 963 cm-1. A band of very low intensity is observed around 948 cm-1 and is assigned to the ν3 antisymmetric stretching vibrations of the (VO3) units. Bands in the range 608-655 cm-1 may be attributed to molecular water librational modes or the stretching modes ￮(V2O2) units. Bands in the range 573-583 cm-1 may be connected with the ￮ (U-Oequatorial) vibrations or ￮ (V2O2) units. Bands located in the range 467-539 cm-1 may be also attributed to the ￮ (U-Oequatorial) units vibrations. The bending modes of the (VO3) units are observed in the 463 to 480 cm-1 range – there may be some coincidence with ￮ (U-Oequatorial). The bending modes of the (V2O2) in the (V2O8) units are located in a series of bands around 407, 365 and 347 cm-1 (ν2). Two intense bands are observed in the 304 to 312 cm-1 range and 241 to 264 cm-1 range and are assigned to the doubly degenerate ν2 modes of the (UO2)2+ units. The study of the vibrational spectroscopy of uranyl vanadates is complicated by the overlap of bands from the (VO3) and (UO2)2+ units. Raman spectroscopy has proven most useful in assigning bands to these two units since Raman bands are sharp and well separated as compared with infrared bands. The uranyl vanadate minerals are often found as crystals on a host matrix and Raman spectroscopy enables their in-situ characterisation without sample preparation

Organic farming in the uplands – appraisal of a development programme

There is a widespread assumption that conversion of livestock production systems in the uplands can be achieved with minimal change to existing hill farming practices and yet still deliver environmental and financial benefits. This assumption needs to be examined because conversion of upland farm enterprises poses particular issues for organic farming, Frost (1999). The certifying bodies acknowledge that some of these issues are not adequately covered by the current standards for organic agriculture. The development of a hill farming organic system at Pwllpeiran was established to provide evidence for such an appraisal, Powell (1999). Appraisal of the project indicates that organic beef and sheep production can be a viable option in the uplands. Long term maintenance of clover content, the relationship between organic production, environmental conservation and veterinary treatment of livestock remain issues that require longer term study

The State Secrets Privilege and Separation of Powers

Since September 11, 2001, the Bush administration has repeatedly invoked the state secrets privilege in cases challenging executive conduct in the war on terror, arguing that the very subject matter of these cases must be kept secret to protect national security. The executive\u27s recent assertion of the privilege is unusual, in that it is seeking dismissal, pre-discovery, of all challenges to the legality of specific executive branch programs, rather than asking for limits on discovery in individual cases. This essay contends that the executive\u27s assertion of the privilege is therefore akin to a claim that the courts lack jurisdiction to hear and decide such cases. The executive\u27s recent invocation of the privilege raises a concern that has been largely overlooked thus far - the impact of the privilege on legislative power to assign jurisdiction to the federal courts. The U.S. Constitution grants to Congress, and not the President, near-plenary authority to craft federal jurisdiction. Furthermore, when Congress assigns federal courts to hear cases challenging the legality of executive action, it is enlisting the judiciary as its partner in policing executive conduct. The executive\u27s recent use of the privilege disrupts that constitutional collaboration, leaving the executive potentially unchecked by any branch of government. The Essay then discusses how courts should incorporate the concern for legislative power and executive oversight into its analysis of the state secrets privilege. It concludes by suggesting that courts refuse to dismiss these cases until Congress has indicated a willingness to take back the task of executive oversight that it had delegated to the courts through the original jurisdictional grant

Organic Farming at ADAS PwllPeiran 1993 - 2001

Agriculture at Pwllpeiran has a long history. Pwllpeiran was eventually established as an Experimental Husbandry Farm in 1955. During the following forty years, work at the farm achieved substantial improvements in the quality and quantity of lamb and beef produced, but by the turn of the millennium the emphasis of agricultural policy was turning away from increased livestock production per se and towards the development of environmentally sensitive farming systems. The 1,118 ha Pwllpeiran Research Farm is now managed by ADAS Wales. The land is rented from the National Assembly for Wales and the Forestry Commission. All of the land is under a ‘whole farm’ Environmentally Sensitive Area agreement. The results from the Pwllpeiran unit underline the difficulties of organic farming in a severely disadvantaged upland area. The unit’s performance demonstrates the potential for production of organic lamb and beef but it also indicates some of the limitations on organic production. Organic farming theory and practice developed primarily in the lowlands and on mixed farms and these origins remain clearly evident in current standards for organic agriculture. Farming in the hills and uplands is, however, in many ways distinct. The lack of opportunity to grow arable crops, the difficulties of growing legumes such as clover and the shortages of farmyard manure, organic fertilisers and farm produced feed all represent particular challenges to the organic hill farm. At Pwllpeiran, production has been constrained by declining soil fertility which in turn has had an adverse effect on grass / clover production and thus on herbage availability and forage conservation. The system operated to date has not produced enough FYM to maintain soil nutrient levels in all of the organic pastures, a major constraint on the level of production. This leads to two important conclusions regarding organic farming in the uplands. The first is the importance of regular and systematic soil sampling to identify possible nutrient deficiencies. The second is the need for sector bodies to recognise that organic farming in severely disadvantaged high rainfall hill areas may require more regular input of permitted P and K fertilisers than lowland and mixed farms. Without such inputs production levels are likely to fall in the medium to long-term and more work needs to done on the best method of supplying these nutrients to the organic hill farm. At Pwllpeiran the decision was taken to accept a lower stocking rate on the organic unit, and to maintain financial performance by generating extra income from ESA agri environment payments and organic premiums. The unit’s experience demonstrates that combining organic farming with environmental conservation schemes on the mountain farm may add to the unit’s income, but environmental prescriptions will also place further limits on production. The balance of advantages to the organic hill farm offered by entry into an environmental management scheme needs to be weighed carefully. The future viability of the Pwllpeiran organic unit depends on maintaining farm income levels by optimising herbage and forage production and utilisation, and by controlling input costs, and producing quality beef and lamb. The impact of other factors like market prices, global trade and government policy will prove equally important. Control of these lies beyond the farm gate

92nd Commencement Senior Class Speaker\u27s Address

Riordan Frost offers advice and the quotes of others for his classmates to consider. He states he has argued for moral relativism in a classroom, but believes that there is goodness in the world, and that it cannot be suppressed. He advises his classmates to always give back to their community. The best cities are founded on a sense of civic responsibility, from ancient times to today