Thermoluminescence properties of natural zoisite mineral under gamma-irradiations and high temperature annealing

Natural silicate mineral of zoisite, Ca(2)Al(3)(SiO(4))(Si(2)O(7))O(OH), has been investigated concerning gamma-radiation, UV-radiation and high temperature annealing effects on thermoluminescence (TL). X-ray diffraction (XRD) measurement confirmed zoisite structure and X-ray fluorescence (XRF) analysis revealed besides Si, Al and Ca that are the main crystal components, other oxides of Fe, Mg, Cr, Na, K, Sr, Ti, Ba and Mn which are present in more than 0.05 wt%. The TL glow curve of natural sample contains (130-150), (340-370) and (435-475)degrees C peaks. Their shapes indicated a possibility that they are result of composition of two or more peaks strongly superposed, a fact confirmed by deconvolution method. Once pre-annealed at 600 degrees C for 1 h, the shape of the glow curves change and the zoisite acquires high sensitivity. Several peaks between 100 and 400 degrees C appear superposed, and the high temperature peak around 435 degrees C cannot be seen. The ultraviolet radiation, on the other hand, produces one TL peak around 130 degrees C and the second one around 200 degrees C and no more. (C) 2010 Elsevier B.V. All rights reserved.

Bendadaite, a new iron arsenate mineral of the arthurite group

Bendadaite, ideally Fe(2+)Fe(2)(3+)(AsO(4))(2)(OH)(2 center dot).4H(2)O, is a new member of the arthurite group It was found as a weathering product of arsenopyrite on a single hand specimen from the phosphate pegmatite Bendada. central Portugal (type locality) Co-type locality is the granite pegmatite of La via do Almerindo (Almerindo mine), Linopolis, Divmo das Laranjeiras county, Minas Gerais, Brazil Further localities are the Vein Negra mine, Copiapo province, Chile, mid-East, Bou Azzer district, Morocco, and Para Inferida yard, Fenugu Sibirt mine, Gonnosfanadiga, Medio Campidano Province, Sardinia. Italy Type bendadaite occurs as blackish green to dark brownish tufts (<0 1 mm long) and flattened radiating aggregates. in intimate association with an intermediate member of the scorodite-mansfieldite series It is monoclinic. space group P2(l/c). with a = 10 239(3) angstrom. b = 9 713(2) angstrom, c = 5 552(2) angstrom. beta = 94 11(2)degrees. = 550 7(2) angstrom(3). Z = 2 Electron-microprobe analysis yielded (wt %). CaO 0 04, MnO 0 03. CuO 006, ZnO 004. Fe(2)O(3) (total) 43 92, Al(2)O(3) 115. SnO(2) 0 10, As(2)O(5) 43 27. P(2)O(5) 1 86, SO(3) 0.03 The empirical formula is (Fe(0 52)(2+)Fe(0 32)(3+)rectangle(0 16))(Sigma 1 00)(Fe(1 89)(3+)Al(0 11))(Sigma 2 00)(As(1 87)P(0 13))(Sigma 2 00)O(8)(OH)(2 00) 4H(2)O based. CM 2(As,P) and assuming ideal 80, 2(OH), 4H2O and complete occupancy of the ferric on site by Fe(3+) and Al Optically, bendadaite is biaxial, positive, 2V(est) = 85+/-4 degrees, 2V(eale) = 88 degrees, with alpha 1 734(3). 13 1 759(3), 7 1 787(4) Pleochrosim is medium strong X pale reddish brown. Y yellowish brown, Z dark yellowish brown. absorption Z > V > X, optical dispersion weak, r > v. Optical axis plane Is parallel to (010), with X approximately parallel to a and Z nearly parallel to c Bendadaite has vitreous to sub-adamantine luster, is translucent and non-fluorescent It is brittle, shows irregular fracture and a good cleavage parallel to 1010} 3 15 0 10 g/cm(3), 3 193 g/cm3 (for the empirical formula) The five strongest powder diffraction lines [d in angstrom (I)(hkl] are 10 22 (10)(100), 7 036 (8)(110), 4 250 (5)(11 I), 2 865 (4)(311), 4 833 (3)(020,011) The d spacings are very similar to those of its Zn analogue, ojelaite The crystal structure of bendadaite was solved and refined using a crystal from the co-type locality with the composition (Fe(0 95)(2+)rectangle(0 05))(Sigma 1 00)(Fe(1 80)(3+)Al(0 20))Sigma(2 00)(As(1 48)P(0 52))(Sigma 2 00)O(8)) (OH)(2) 4H(2)O (R = 16%) and confirms an arthurite-type atomic arrangement

Crystal structure of the (Mg,Fe)[UO2(P,As)O-4](2) center dot 10H(2)O solid solution - A novel mineral variety of saleeite

The crystal structure of a novel variety {[(Mg0.81Fe0.19)(H2O)(6)](H2O)(4)}{(UO2)[(P0.67As0.33)O-4]}(2) of the mineral saleeite is determined using X-ray diffraction (Bruker Smart diffractometer, lambda MoK alpha, graphite monochromator, 2 theta(max) = 56.62 degrees, R = 0.0321 for 2317 reflections, T = 100 K). The main crystal data are as follows: a = 6.952(6) angstrom, b = 19.865(5) , angstrom, c = 6.969(2) angstrom, beta = 90.806(4)degrees, space group P12(l)/n1, Z = 2, and P-calcd = 3.34 g/cm(3). It is shown that the structure is formed by alternating (along the [010] direction) anionic layers, which are composed of uranium bipyramids and T(P,As) tetrahedra, and cation layers consisting of M(Mg, Fe) octahedra and water molecules, which are joined through a system of asymmetric hydrogen bonds. The hydrogen atoms are located, the scheme of hydrogen bonds is established, and their geometric characteristics are calculated.

THE CRYSTAL STRUCTURE OF A MICROLITE-GROUP MINERAL WITH A FORMULA NEAR NaCaTa(2)O(6)F FROM THE MORRO REDONDO MINE, CORONEL MURTA, MINAS GERAIS, BRAZIL

We present electron-microprobe and single-crystal X-ray-diffraction data for a microlite-group mineral with a formula near NaCaTa(2)O(6)F from the Morro Redondo mine, Coronel Murta, Minas Gerais, Brazil. On the basis of these data, the formula is A(Na(0.88)Ca(0.88)Pb(0.02)square(0.22))(Sigma 2.00) (B)(Ta(1.70)Nb(0.14)Si(0.12)As(0.04))(Sigma 2.00) (X)[(O(5.75)(OH)(0.25)](Sigma 6.00) (Y)(F(0.73)square(0.27))(Sigma 1.00). According to the new nomenclature for the pyrochlore-supergroup minerals, it is intermediate between fluornatromicrolite and "" fluorcalciomicrolite"". The crystal structure, F (d3) over barm, a = 10.4396(12) angstrom, has been refined to an R(1) value of 0.0258 (wR(2) = 0.0715) for 107 reflections (MoK alpha radiation). There is a scarcity of crystal-chemical data for pyrochlore-supergroup minerals in the literature. A compilation of these data is presented here.

A renewable copper electrode as an amperometric flow detector for nitrate determination in mineral water and soft drink samples

A novel approach was developed for nitrate analysis in a FIA configuration with amperometric detection (E=-0.48 V). Sensitive and reproducible current measurements were achieved by using a copper electrode activated with a controlled potential protocol. The response of the FIA amperometric method was linear over the range from 0.1 to 2.5 mmol L(-1) nitrate with a detection limit of 4.2 mu mol L(-1) (S/N = 3). The repeatability of measurements was determined as 4.7% (n=9) at the best conditions (flow rate: 3.0 mL min(-1), sample volume: 150 mu L and nitrate concentration: 0.5 mmol L(-1)) with a sampling rate of 60 samples h(-1). The method was employed for the determination of nitrate in mineral water and soft drink samples and the results were in agreement with those obtained by using a recommended procedure. Studies towards a selective monitoring of nitrite were also performed in samples containing nitrate by carrying out measurements at a less negative potential (-0.20 V). (C) 2009 Elsevier B.V. All rights reserved.

The impact of foreign direct investment and openness on Vietnamese economy

This thesis examines the impact of foreign direct investment (FDI) on Vietnamese economy based on Partial Adjustment Model and time series data from 1976 to 2004. FDI is shown to have not only short run but also long run effect on gross domestic product (GDP) of Vietnam. However, elasticity of GDP with respect to FDI is small and it will take many years to fully manifest itself. The impact of trade openness on GDP has also been examined and it is shown to be stronger than that of FDI. The paper offers a number of explanations and discusses briefly suggestions in order to increase the contribution of FDI to Vietnam’s economic development.

The Impact of Foreign Direct Investment on International Trade: An Empirical Study of China

This paper investigates the impact of inward FDI (Foreign Direct Investment) on international trade of China empirically on the country level by using panel data from 1984 to 2007. Two separate transformed models which are based on the gravity equation and refer to the econometric models of some previous studies, are used in this paper to estimate the effect of FDI inflows on exports and imports respectively. The estimation results confirmed the complementary relationship between FDI inflows and trade of China both on exports and imports, which has also been supported by previous empirical studies.

An analysis of linkage between foreign direct investment and GDP per Capita in Pakistan : A time series analysis

This study aims to investigate the relation between foreign direct investment (FDI) and per capita gross domestic product (GDP) in Pakistan. The study is based on a basic Cobb-Douglas production function. Population over age 15 to 64 is used as a proxy for labor in the investigation. The other variables used are gross capital formation, technological gap and a dummy variable measuring among other things political stability. We find positive correlation between GDP per capita in Pakistan and two variables, FDI and population over age 15 to 64. The GDP gap (gap between GDP of USA and GDP of Pakistan) is negatively correlated with GDP per capita as expected. Political instability, economic crisis, wars and polarization in the society have no significant impact on GDP per capita in the long run.

The association between the investment opportunity set and corporate financing and dividend decisions: some Australian evidence

Summarizes previous research on the investment opportunity set (IOS) using price-based and investment-based proxies and variance measures; and develops hypotheses on the relationship between IOS, debt/equity ratios and dividend policies. Tests them on 1990-1998 data from listed Australian companies and explains the methodology, which builds on Gover and Gover (1993) by including more recent proxy variables. Finds no significant results from low growth firms, although some high growth firms show lower debt/equity ratios and dividends. Questions the robustness of existing IOS proxies in the Australian context and calls for further research.

Tax incentives for foreign direct investment part II : Design considerations

Part I of this article concluded that tax incentives for foreign direct investment (FDI) have become increasingly common over the past 10 years or so, especially among developing countries, and that there is substantial evidence to support the proposition that tax considerations now play an important role in many investment decisions. Countries seeking to attract FDI often feel compelled to offer tax inducements that are at least as attractive as those offered by their neighbours or competitors. Countries do so at a cost, however, and that cost may be substantial. Governments are thus placed in a dilemma - can they afford to cut taxes in order to attract investment, and can they afford not to? The second part of this article assumes that countries, and especially most developing countries, will continue to feel obliged to provide tax incentives. The aim of this part therefore is to examine ways in which those incentives can be made more effective and more efficient, thereby reducing their cost to the host country.

Tax incentives for foreign direct investment part I : Recent trends and countertrends

According to the conventional wisdom, tax incentives for investment - in particular for foreign direct investment (FDI) - are not recommended. That is the view held almost universally by theorists and by the international bodies that advise on tax matters.' Tax incentives are bad in theory and bad in practice. They are bad in theory principally because they cause distortions: investment decisions are made that would not have been made without the inducement of special tax concessions. They are bad in practice, being both ineffective and inefficient. They are ineffective in that tax considerations are only rarely a major determinant in FDI decisions; they are inefficient because their cost, in terms of tax revenue foregone, often far exceeds any benefits they may produce. Other criticisms are also frequently levelled against tax incentives for FDI - they are inequitable (since they benefit some investors but not others), they are difficult to administer and open to abuse, and they lack transparency. Thus, it is not surprising that ''the standard advice given by institutions like the World Bank and the lMF to developing countries is to refrain from offering tax incentives to foreign investors".2 The purpose of this article is not to question that advice or to challenge the conventional wisdom - except in one respect. Recent evidence does suggest that tax considerations are an increasingly important factor in investment decisions and that special tax incentives have become substantially more effective as instruments for attracting FDI than they were 10 or 20 years ago.3 The first part of this article, published here, examines some of that evidence, reviews some recent trends in national policies towards FDI, attempts to suggest why investment incentives have become more important and more effective, and looks at the pressures that are exerted on governments, especially in developing countries, to compete for FDI by offering special incentives. The second part of the article, to be published in the Bulletin next month, assumes that many countries will continue to offer tax incentives to investors regardless of the best advice, and considers how incentives might be designed in order to increase their effectiveness and efficiency.

A multi-agent framework for financial investment planning

If a company or person wants to invest a lot of money, where, when, and how should the investment go? A multi-agent based Financial Investment Planner may give some reasonable answers to the above question. Good advice is mainly based on adequate information, rich knowledge, and great
skills to use knowledge and information. To this end, this planner consists of four principal components information gathering agents that are responsible for gathering relevant information on the Internet, data mining agents that are in charge of discovering knowledge from retrieved information as well as other relevant databases, group decision making agents that can effectively use available knowledge and appropriate information to make reasonable decisions (investment advice), and a graphical user interface that interacts with users. This paper is focused on the group decision making part. The design and implementation of an agent-based hybrid intelligent system - agent-based soft computing society are detailed.

Exports, Inward Foreign Direct Investment (FDI) and Regional Economic Growth in China

The relationship between exports and economic growth is strong in developing economies. Both externality effects of exports on the non-exports sector and higher marginal productivity in the exports sector in relation to the non-exports sector play an important role in promoting exports and GDP growth. The underlying theoretical model of FEDER, 1982, is used with the data on the Chinese provinces and it is shown that the economic structure, degree of openness and policy environment have a significant role in the relationship between exports and economic growth.

Foreign Direct Investment and Regional Export Performance in China

This paper investigates the impact of foreign direct investment (FDI) on the export performance of China at the provincial level. First, it presents a theoretical discussion of the impact of FDI on foreign trade, and then an empirical study of the impact of FDI on the export performance of regions in Chin. It has been found that the impact of FDI on exports differs across three macro-regions in China. The effect is stronger in the coastal region than in the inland regions. Although FDI shows a positive and significant impact on exports from the central region, its impact on the western region is found to be insignificant.

Investment opportunities and leverage: some Australian evidence on the role of board monitoring and director equity ownership

This paper tests the hypothesis that the negative relationship between investment opportunity set (IOS) and debt is moderated by board monitoring and director equity ownership. According to contracting theory, firms with high growth opportunities (high IOS) are associated with lower levels of debt as a result of the asset substitution and the under-investment problem. However, our hypotheses test the conjecture that the negative debt / IOS relationship will be moderated by the proportion of non-executive directors (NEDs) on the board and director equity ownership. NEDs provide higher monitoring which reduces management discretion while director equity ownership provides incentives for managers to maximize the value of the firm. More specifically, we expect that high growth firms with a higher proportion of non-executive directors and director equity ownership are less likely to be associated with asset substitution and under investment. Thus, the negative investment opportunity set / debt relationship will be weaker for firms with higher levels of non-executive directors and high director equity ownership. Data collected from Australian companies support both these two hypotheses. Results have significant implications for corporate finance theory.