On the nature of spin- and orbital-resolved Cu+−NOCu^{+}-NO charge transfer in the gas phase and at Cu(I) sites in zeolites

Electronic factors essential for NO activation by Cu(I) sites in zeolites are investigated within spin-resolved analysis of electron transfer channels (natural orbitals for chemical valence). NOCV analysis is performed for three DFT-opti- mized models of Cu(I)–NO site in ZSM-5: [CuNO] ? , (T1)CuNO, and (M7)CuNO. NO as a non-innocent, open- shell ligand reveals significant differences between inde- pendent deformation density components for a and b spins. Four distinct components are identified: (i) unpaired electron donation from NO p k * antibonding orbital to Cu s,d ; (ii) backdonation from copper d yz to p \ * antibonding orbital; (iii) donation from occupied p k and Cu d xz to bonding region, and (iv) donation from nitrogen lone-pair to Cu s,d . Channel (i), corresponding to one-electron bond, shows-up solely for spin majority and is effective only in the interaction of NO with naked Cu ? . Channel (ii) dominates for models b and c: it strongly activates NO bond by populating antibonding p * orbital and weakens the N–O bond in contrast to channel (i), depopulating the antibonding orbital and strengthening N–O bond. This picture perfectly agrees with IR experiment: interaction with naked Cu ? imposes small blue-shift of N stretching frequency while it becomes strongly red-shifted for Cu(I) site in ZSM-5 due to enhanced backdonation

Symptoms of overactive bladder (OAB) in patients treated for depressive disorders

Aim: The aim of the study was to investigate the correlation between symptoms of overactive bladder (OAB) and severity of depressive symptoms in patients treated for depression. Method: 102 patients (43 males, 59 females) aged 20–67 (M = 46.1±11,3) treated for depression were included in this cross-sectional analysis. OAB symptoms were examined with the International Prostate Symptom Score (IPSS) and International Consultation on Incontinence Questionnaire Overactive Bladder Module (ICIQOAB). OAB-related quality of life was assessed with the International Consultation on Incontinence Questionnaire Overactive Bladder Quality of Life Module (ICIQ-OABqol). Depressive symptoms were assessed with the 17-item Hamilton Depression Rating Scale (HDRS) and Quick Inventory of Depressive Symptomatology - Self Report (QIDS-SR). Results: Symptoms of OAB assessed with IPSS and ICIQ-OAB were more severe in women than in men. In the entire group highest scores in IPSS of assessed OAB symptoms were observed in nocturia (1,53±1,64) followed by urinary frequency (1,19±1,48) and lowest in urgency (0,80±1,28). Symptoms of OAB (based on the ICIQOABqol total score) were more bothersome in women (48,74±29,18), than in men (39,18±17,70). In the whole group and in women the QIDS-SR total score correlated with the ICIQ-OAB score ( p < 0,05). The total QIDS-SR score correlated with the ICIQ-OABqol score in entire group (p < 0,05), in women (p < 0,05) and in men (p < 0,05). Patients suffering from at least moderate depression assessed with QIDS-SR had significantly more pronounced symptoms of urinary frequency (p = 0,005) and urgency (p = 0,039). A number of other significant (p < 0.05) correlations were observed between the total ICIQ-OAB score and certain items’ scores in the GHQ-30 both in women. Conclusions: OAB symptoms are common among patients treated for depressive disorders. There is a correlation between severity of depressive symptoms and OAB. OAB is bothersome and affects the quality of life in patients treated for depression. Comorbidity of OAB and depression has clinical significance and that should enhance interdisciplinary treatment approaches. Due to limitations of this study, further researches are essential to reveal more details of the correlation between OAB and depression

Basic Properties of ZnO, Ga₂O₃, and MgO—Quantitative IR Studies

In our previous study, we elaborated a method of determination of concentrations of the basic sites O2− and OH− in a quantitative IR study of CO2 adsorption. Previous adsorption studies or TPD experiments only provided the total basicity without distinguishing between O2− and OH−. In this study, we determined the concentration of O2− and OH− on ZnO, Ga2O3, and MgO surfaces. The basicity of ZnO and MgO was found to be significantly higher than that of Ga2O3. The surface of ZnO was rich in O2−, the contribution of OH− was very small, and the Ga2O3 surface contained mainly OH−. For MgO, the contribution of O2− and OH− was comparable. According to the IR results, only a small fraction of all surface hydroxyls were sufficiently basic to react with CO2. The partial dehydroxylation changed the proportion of the concentrations of O2− and OH− on the oxides. We also elaborated upon a new method to determine the total concentration of basic sites via CO2 desorption monitored using IR. For all the oxides, we studied the sum of the concentrations of O2− and OH−, as determined in our quantitative IR studies, to find whether they were comparable with the total basicity determined in the desorption experiments

Basic Sites on Alumina with Preadsorbed Ethanol and Ammonia—An IR Study

The adsorption of ethanol and ammonia changes the basic properties of alumina, and new basic sites are created. Ethanol reacts with surface Al-OH groups, forming ethoxy group Al-O-C2H5. The substitution of Al-OH by Al-O-C2H5 increases the negative charge of neighbouring oxygen atoms, and they became sufficiently basic to react with adsorbed CO2 forming carbonate species CO32−. These carbonates were found to be monodentate and bidentate species. Preadsorption of ammonia also increases the basicity of alumina, but the mechanism is different than for ethanol adsorption. Adsorbed ammonia interacts with surface Lewis acid sites being three-coordinated aluminium atoms. This interaction is accompanied by an electron transfer from ammonia molecules to surface sites, and increases the basicity of the neighbouring oxygens, which can react with the absorbed CO2. The carbonate species formed are polydentate ones

Ethoxy Groups on ZrO2, CuO, and CuO/ZrO2 Studied by IR Spectroscopy

The formation, properties, decomposition and reactions of ethoxy groups on ZrO2, CuO, and CuO/ZrO2 were followed by IR spectroscopy. The reaction of ethanol with terminal Zr-OH groups leads to the formation of monodendate ethoxy groups (type I), whereas the reaction of ethanol with tribridged Zr-OH grups results in the formation of bidendate ethoxyls (type II). In both cases, water is produced. Ethoxy groups of type II were also formed on CuO. The type of the surface species detected after interaction of ethanol with CuO/ZrO2 was the same as detected for both oxides (i.e., ZrO2 and CuO) separately. This suggests that no new phase was formed in the mixed oxide system. At higher temperatures, ethoxy groups were oxidized forming acetate ions. Gaseous ethanol present in the cell was oxidized to acetaldehyde without the intermediacy of ethoxy groups