Effect of Graphene and MoS2 Flakes in Industrial Oils to Enhance Lubrication.

Tribological studies of the 2D nanoadditives such as MoS2 and graphene are mostly performed in base oils such as SN500, SN150, or paraffin. We have focused on their effect in lubrication properties of industrial oils (e.g., axle, transmission, and compressor oils) along with SN500 oil employing a four-ball tester. Two types of graphene powders (GpowA with fewer defects than GpowC), MoS2 powder, and their physical mixtures are chosen as nanoadditives. The tribology performance for 0.05 wt% of additives in various industrial oils is evaluated by monitoring the coefficient of friction (COF) during rubbing and wear scar diameter (WSD) of the steel balls after rubbing. Elemental analysis and electron microscopy have been performed on the wear surfaces for evidence of any tribofilm formation. GpowA favors antifriction for axle and transmission oils with 40% reduction in axle oil, whereas it improved antiwear properties in most of the oils. GpowC shows a COF decrement by 12% only for compressor oil, but contribute to wear reduction in all oils. The observed COF reduction is attributed to the compatibility of nonfunctionalized GpowA with nonpolar axle oil and functionalized GpowC with polar compressor oil. MoS2 shows a decrease in the COF and WSD in most industrial oils; the best being 60% COF and 7% WSD reduction in axle oil. For additives in oils that favor antiwear, flakes or particles are observed on the wear surface supported by the higher elemental contribution of the constituents from the wear region. The mixtures of GpowA or C with MoS2, however, does not seem to favor improvement in the COF or WSD in industrial oils. With assistance from oleylamine surfactants, the lubrication properties of most additives are improved, particularly for the mixtures with 12-15% COF reduction and 4-7% WSD reduction in compressor oil. The study indicates that a large sheet size of high-quality graphene aids antifriction and addition of surfactant molecules facilitates a co-operative effect between MoS2 and graphene for improved tribology.

Single sea urchin-MoO3 nanostructure for surface enhanced Raman spectroscopy of dyes.

Enhancing the surface-enhanced Raman scattering (SERS) activity of semiconductor metal oxide nanostructures by controlling the morphology and oxygen vacancies towards trace detection of organics is of significant interest. In this study, MoO3 with a novel sea urchin morphology is synthesized employing chemical bath deposition and consists of hundreds of ∼15 µm long spikes originating from the core forming 20-40 micron globular structures. The spikes taper to form 20 nm sharp tips. SERS of rhodamine 6G (R6G) over MoO3 sea urchins has been investigated and compared to that of 1D h-MoO3 nanorod arrays. The SERS activity is morphology dependent and the sea urchin-like morphology exhibits higher SERS activity with an enhancement factor (EF) of the order 105 and a detection limit of 100 nM, while for h-MoO3 nanorods, the corresponding values are 103 and 1 µM, respectively. X-ray photoelectron spectroscopy reveals a high concentration of Mo+5 states in sea urchins indicating lattice oxygen vacancies. The observed EF is quite high for a metal oxide substrate and is attributed to the enhanced charge transfer between analyte molecules and the substrate promoted by the oxygen vacancies along with surface defects and hydroxyl groups on MoO3 sea urchins providing more active sites for the adsorption of probe molecules. The role of oxygen vacancies is confirmed by the lower EF value exhibited by the stoichiometric 1D h-MoO3. Raman mapping of a single sea urchin is achieved with good R6G intensity and indicates that the tips of spiky features are involved in SERS enhancement. The reusability of substrates is shown for repeated cycles of R6G adsorption by UV irradiation exploiting the photocatalytic activity of MoO3 nanostructures.

Changes in abortion service provision in Bihar and Jharkhand states, India between 2004 and 2013.

BACKGROUND: The Medical Termination of Pregnancy (MTP) Act of 1971 liberalized abortion laws in India. This study examines changes in abortion service provision and characteristics of abortion providers in Bihar and Jharkhand states, India between 2004 and 2013. METHODS: We used state-representative data from cross-sectional surveys of reproductive health service providers we conducted in 2004 (N = 1,323) and 2012/2013 (N = 1,020). We employed chi-squared tests to examine and compare abortion providers' characteristics, and fitted separate multivariate logistic regression models for provision of surgical, medical, and any abortion services, respectively, adjusting for potential confounders to identify factors associated with abortion service provision at the two survey time points. RESULTS: Of providers interviewed in 2004 and 2012/2013, 63.7% and 84.5%, respectively, offered abortion services. Among abortion providers, 21.1% offered surgical and 10.7% offered medical abortions in 2004; 15.8% and 94.1% did so, respectively, in 2012/2013. Private providers were more likely than public providers to offer abortion services at both time points. Compared to female providers, male providers were significantly less likely to provide both surgical and medical abortions in 2004, and significantly less likely to provide surgical abortions in 2012/2013. Pharmacists and community health workers played increasingly important roles in abortion service provision, especially medical abortion, during the period. CONCLUSION: This study documents important changes in abortion provision in the two Indian states during 2004-2013.

Gender inequality and the risk of HIV among married couples in North India.

This study investigated the distribution and determinants of HIV risks among married couples in North India. Gender inequality emerged as a potential driver of HIV risks in this region. Data collection took place in 2003 in a probability survey of 3385 couples living in India's most populous state - Uttar Pradesh - and Uttaranchal. Couples' analyses utilizing generalized estimating equations showed that compared with husbands, wives were less knowledgeable about HIV (OR = 0.31, 95% CI = 0.27-0.36), more likely to consider themselves at risk for infection (OR = 6.86, 95% CI = 4.65-10.13), and less likely to feel that a wife had the right to refuse sex with her husband (OR = 0.50, 95% CI = 0.44-0.58). The proportion of husbands reporting non-marital sex in the past year was 7.1% and transactional sex in the past year, 2.2%. Among their wives, 73.4% were unaware of their husbands' non-marital sexual behaviors and only 28.9% of husbands reported condom use during their last non-marital sexual encounter. Logistic regression analyses showed that husbands' alcohol use, husbands' mobility, and urban residence were positively associated with husbands' non-marital sexual behaviors adjusting for other covariates. The data demonstrate that HIV prevention programs among couples in North India should consider both sexual risks and gender inequalities which potentially fuel HIV spread in this region.

Couple Interaction and Predicting Vulnerability to Domestic Violence in Uttar Pradesh, India.

Domestic violence, when conducted against women, is a type of gender-based violence that negatively impacts a woman's physical and psychological health, causing insecurity, lack of safety, and loss of health and self-worth. Domestic violence is an important consideration for sexual, reproductive, and child health, as it can affect contraceptive behaviors of couples as well as levels of infant mortality. In the present analysis, an attempt has been made to study the relationship between women's experience of domestic violence and couple interaction after controlling for certain socioeconomic and demographic variables using logistic regression. This study looks at data from the National Family Health Survey-III conducted from 2005 to 2006 in Uttar Pradesh, the most populous state of India. Findings reveal that 43% of women suffer from domestic violence in the society as a whole; however, if a couple makes joint decisions in household matters, the prevalence of domestic violence is observed to be 24% less. Education and occupation of women, standard of living, media exposure, and partner's alcoholic behaviors are also found to be possible predictors of domestic violence.