ABSTRACT
The oxidation of citronellal to citronellic acid was studied using molecular oxygen as oxidant and gold-containing supported catalysts under aqueous conditions. The reactions were carried out at 60-90 degrees C, with 200 Nml min(-1) O2 and at pH values from 9 to 12. The alumina- or titania-supported catalysts were synthesized according to the deposition-precipitation procedure using urea or NaOH. Mechanistic studies have revealed that radical-initiated reactions lead to undesired by-products especially at pH <9, that is, the C=C bond is attacked and a diol is primarily formed probably via an epoxide intermediate. This side reaction can be suppressed to a large extent by increasing the pH to 12 and by raising the catalyst/oxygen ratio. Furthermore, detailed studies on the influence of reaction time, pH value, reactant concentration and amount of catalyst show that citronellic acid can be obtained in over 90% yield with total conversion of citronellal at pH 12 and a temperature of 80 degrees C.
Subject(s)
Aldehydes/chemistry , Caprylates/chemistry , Gold/chemistry , Metal Nanoparticles/chemistry , Monoterpenes/chemistry , Oxygen/chemistry , Acyclic Monoterpenes , Catalysis , Conservation of Natural Resources , Hydrogen-Ion Concentration , Oxidation-Reduction , Time FactorsABSTRACT
In a clinical multicenter observational study including 584 women attended by 99 participating gynaecologists the quality of life changes after 3 month use of an oral contraceptive preparation containing 30 mcg ethinylestradiol (EE) and 3 mg drospirenone was evaluated through the use of a self developed questionnaire using 20 items with a 5 scale answer scheme. We found a mean positive change of life quality of 7.3%. Significant changes were observed regarding subjective experiences of weight, skin, hair, cycle, attractivity, libido and mental wellbeing.
Subject(s)
Androstenes , Contraceptives, Oral , Ethinyl Estradiol , Progesterone Congeners , Quality of Life , Adult , Androstenes/administration & dosage , Body Weight , Contraceptives, Oral/administration & dosage , Data Interpretation, Statistical , Ethinyl Estradiol/administration & dosage , Female , Follow-Up Studies , Humans , Libido , Menstruation , Progesterone Congeners/administration & dosage , Surveys and Questionnaires , Time FactorsABSTRACT
The elderly frequently experiences demotivation as a sign of depression. Demotivation often results in failures of relationships and isolation increases confusion of the demotivated individuals who are often additionally impaired by physical illness or its sequels. The elderly exposes himself to an affective dependence on engaged services or relationships. Motivation is also threatened by consequences of physical dependence which alters self-esteem. The difficulty to adapt to new situations adds up with poor social integration in an increasingly complex environment. This often precludes loss of ability to execute personal decisions and to cope with daily activities. This all accentuates dependence and depression and promotes further withdrawal. Impairment of cognitive functions and withdrawal increase the burden of familial suffering. We propose solutions adapted to demotivated elderly people in order to reintegrate them in their family and daily life.
