High precision measurement of silicon in naphthas by ICP-OES using isooctane as diluent.

An analytical protocol for the accurate and precise determination of Si in naphthas is presented by using ICP-OES, optimizing from the sample preparation to the measurement conditions, in order to be able to analyze for the first time silicon contents below 100µgkg-1 in a relatively short time thus being used as a control method. In the petrochemical industry, silicon can be present as a contaminant in different petroleum products such as gasoline, ethanol, or naphthas, forming different silicon compounds during the treatment of these products that are irreversibly adsorbed onto catalyst surfaces decreasing its time life. The complex nature of the organic naphtha sample together with the low detection limits needed make the analysis of silicon quite difficult. The aim of this work is to optimize the measurement of silicon in naphthas by ICP-OES introducing as an improvement the use of isooctane as diluent. The set up was carried out by optimizing the measurement conditions (power, nebulizer flow, pump rate, read time, and viewing mode) and the sample preparation (type of diluent, cleaning process, blanks, and studying various dilution ratios depending on the sample characteristics).

Ethics on the job: a survey. The realities of HIV/AIDS.

HIV/AIDS has had a profound impact on how care is provided to patients--raising both practice and ethical concerns. In this final installment in our series, we'll see how nurses are coping with these dilemmas, and how they feel about issues like mandatory HIV testing and practice restrictions on infected providers.

Ethics on the job: a survey. Where nurses stand on abortion.

PIP: This article examines the attitudes toward abortion among nurses working in an obstetrics/gynecology (OB/GYN) unit in the US. Survey results conducted in 1988 and 1998 were compared. Majority of the nurses (52%) in the 1988 survey said that they would work in an OB/GYN unit where abortions are performed, while 48% would not. The 1998 survey, on the other hand, confirmed that 39% of the respondents would want to work in an OB/GYN unit while the majority (61%) would not. More nurses today refuse to perform abortion unless the procedure is necessary, such as in cases of: 1) rape; 2) incest; and 3) threat to the health or life of the mother. Violence, intimidation, or interference with those who attempt to obtain or provide abortion causes nurses' reluctance to participate. Moral, ethical and religious issues also contribute to the opposition. This legally protected health care service has been declining. Several bills have been passed regarding its prohibition, but none has been successful.^ieng

Ethics on the job: a survey. Staffing issues.

In this fourth installment of our series on ethical issues, we'll examine how patient care is affected when there just aren't enough nurses to go around. We'll look at how nurses are coping with that situation, and how UAPs now factor into the mix.