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Use of the Internet around the globe is on the increase. An estimated 40 million users in the UK alone, now have access to the Internet either at home or at work. However, despite the increase in awareness about the Internet as an information source, people who make use of the Internet for personal or business purposes are generally unaware that whilst browsing the Web they may make their personal information available to the Web sites that they visit.  相似文献   
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Zinc oxide nanoparticles(ZnOnp) are molecular nanoparticles synthesized by a chemical precipitation method from zinc nitrate tetrahydrate and sodium hydroxide.Carbonized sawdust(CSD) was prepared from sawdust obtained from a local wood mill.The matrix of both provides a better material as an adsorbent.The present study applied the functionality of ZnOnp,CSD,and ZnOnp-CSD matrix as adsorbent materials for the removal of Pb(Ⅱ) ions from aqueous solution.The method of batch process was employed to investigate the potential of the adsorbents.The influence of pH,contact time,initial concentration of adsorbate,the dosage of adsorbents,and the temperature of adsorbate-adsorbent mixture on the adsorption capacity were revealed.The adsorption isotherm studies indicate that both Freundlich and Langmuir isotherms were suitable to express the experimental data obtained with theoretical maximum adsorption capacities(q_m) of 70.42,87.72,and 92.59 mg·g~(-1) for the adsorption of Pb(Ⅱ) ions onto ZnOnp,CSD,and ZnOnp-CSD matrix,respectively.The separation factors(R_L) calculated showed that the use of the adsorbents for the removal of Pb(Ⅱ) ions is a feasible process with R_L 1.The thermodynamic parameters obtained revealed that the processes are endothermic,feasible,and spontaneous in nature at 25-50℃.Evaluation of the kinetic model elected that the processes agreed better with pseudo-second order where the values of rate constant(k_2) obtained for the adsorption of Pb(Ⅱ) ions onto ZnOnp,CSD,and ZnOnp-CSD matrix are 0.00149,0.00188,and 0.00315 g·mg~(-1)·min~(-1),respectively.The reusability potential examined for four cycles indicated that the adsorbents have better potential and economic value of reuse and the ZnOnp-CSD matrix indicates improved adsorbent material to remove Pb(Ⅱ) ions from aqueous solution.  相似文献   
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The research evaluated the efficacy of an intervention to reduce the onset and extent of binge drinking during the 1st year of college. The approach was on influencing the students before they start college, through their parents, during the critical time between high school graduation and the beginning of college. Specifically, parents were educated about binge drinking and how to convey information to their teens, and then encouraged to talk with their teens just before their teens embarked on their college education. Teens whose parents implemented the intervention materials were compared with a control sample during their 1st semester on drinking outcomes, perceptions about drinking activities, perceived parental and peer approval of drinking, and drinking-related consequences. As anticipated, teens in the treatment condition were significantly different (p?,?.05)on nearly all outcomes in the predicted directions (e.g., lower drinking tendencies, drinking consequences). The benefits of a parent-based intervention to prevent college drinking are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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There is increasing awareness of the role that metals/minerals play in health and disease. Minerals contribute in essential ways to the fundamental biochemical and physiological functions of cells. Deficit of an essential mineral leads to aberrations in cell function. Alternatively, minerals in excess have significant toxicity, and in an era of increasing threat to a safe environment, the potential for toxic tissue injury to contribute to progressive renal insufficiency and ultimately to unexplained renal failure remains a major concern. This review provides information on selected minerals that are attracting growing attention with respect to their influence on renal function in health and disease. Although all minerals have the potential to cause toxicity if consumed in sufficient quantity, most are essential nutrients whose deficiency is associated with significant health problems. Certain minerals, including aluminum, arsenic, cadmium, lead, and mercury are considered toxic. Their suggested positive effects on the health of animals has been recently summarized, but in humans they are not currently known to exert any clearly beneficial biological or biochemical effect.  相似文献   
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