Comparison of Particle Shape, Surface Area, and Color Properties of the Calcite Particles Ground by Stirred and Ball Mill

Since the particle size, shape, specific surface area, and purity of the ground calcium carbonate (GCC) decide its usability in the paper, paint, and plastic industries, the effect of grinding is important. However, the effect of stirred and ball mill grinding on the particle shape of GCC by dynamic image analysis (DIA) is still lacking in the literature. Therefore, the aim of this study is to compare the aspect ratio at the same fineness (d97 = 50 μm) and evaluate other properties such as color, and surface area of GCC particles by stirred and ball mill grindings. DIA results showed that particles produced by the ball mill had higher aspect ratio values than those by the stirred mill. This was attributed to the impact, and attrition breakage modes produced by the ball and stirred mill, respectively. This conclusion is supported by XRD and SEM. Finally, the results related to physical properties such as aspect ratio, surface area, and whiteness are discussed depending on the usage area of GCC

The effect of liquid grinding aids on the dry fine grinding of muscovite

This paper investigates the production of a micronized muscovite to a target product size of d50~15 μm with a minimum energy consumption to suit the product requirements of the paint industry by a dry grinding process in a laboratory-scale vertical stirred ball mill. A series of batch dry grinding tests were conducted without and with two commonly used industrial liquid grinding aids, ethylene glycol (EG, C2H6O2) and triethanolamine (TEA, C6H15NO3). The results were evaluated based on particle size distribution (PSD), specific energy consumption, span value, and aspect ratio. The results showed that using liquid grinding aids resulted in a finer PSD, lower specific energy consumption, a narrower size distribution, lower span values, and a higher aspect ratio, which meant better delamination and improved grinding efficiency to that of no grinding aid. The interaction between grinding aids and ground muscovite surfaces was investigated by Fourier Transform Infrared Spectroscopy (FTIR). FTIR measurements revealed that EG and TEA were physically adsorbed on muscovite surfaces. Scanning Electron Microscopy (SEM) was also employed to determine differences between ground muscovite surfaces with and without grinding aids. SEM images indicated that grinding aids could prevent the agglomeration of ground muscovite particles while improving delamination. Adding grinding aids led to a decrease in muscovite agglomeration and an improvement in lamination owing to the adsorption of grinding aids on the particle surfaces

Rates of skincare product and cosmetic procedure use in patients with acne vulgaris and the effective factors: A multicenter study with 1,755 patients

Background Skincare products and cosmetic procedures are used as an adjunct or complementary to conventional drug therapy for acne vulgaris (AV). Objective To evaluate the use of skincare products and the frequency of cosmetic procedures in AV treatment. Methods A total of 1,755 patients with AV completed the survey prepared by the researchers and the Cardiff Acne Disability Index (CADI) questionnaire. The clinical findings and the Food and Drug Administration (FDA) severity scores were recorded by the dermatologists. Results For AV, 66.7% of the patients stated that they used skincare products and 26.7% had undergone cosmetic procedures. The use of skincare products was statistically significantly higher in women (female: 74.5%, male: 57.7%, p =%76.8, p < 0.0001). The rate of cosmetic procedures was higher in those with higher CADI scores (users: 7.8 +/- 3.8; non-users: 7.1 +/- 3.96, p < 0.0001); older patients (users: 22.7 +/- 10.7 years; non-users: 21.3 +/- 5 years, p < 0.0001); high school (25.6%); and graduate (28.9%) education (p = 0.043), those with lower disease severity (FDA-1: 31.1%; FDA-2: 28.5%, FDA-3: 27.1%, FDA-4: 20.4%, p = 0.022); smokers (smokers: 32.5%; non-smokers: 25.5%, p = 0.020), and those with AV in the family (present: 29.8%; absent: 24.2%, p = 0.009). The patients most frequently used cleansers (85.2%) as cosmetic products, and most commonly underwent skincare treatment (71%) as an interventional procedure. They mostly learned about such products and methods from the Internet, and 33.3% of the participants had undergone procedures performed by non-physicians. Conclusion The patients generally choose skincare products as a result of their Internet search and sometimes have these procedures performed by non-physicians. Dermatologists should be aware of this situation and inform their patients about appropriate products and procedures

The prevalence of childhood psychopathology in Turkey: a cross-sectional multicenter nationwide study (EPICPAT-T)

Conclusion: This is the largest and most comprehensive epidemiological study to determine the prevalence of psychopathologies in children and adolescents in Turkey. Our results partly higher than, and partly comparable to previous national and international studies. It also contributes to the literature by determining the independent predictors of psychopathologies in this age group

The prevalence of childhood psychopathology in Turkey: a cross-sectional multicenter nationwide study (EPICPAT-T).

Aim: The aim of this study was to determine the prevalence of childhood psychopathologies in Turkey

Prevalence of Childhood Affective disorders in Turkey: An epidemiological study

Aim: To determine the prevalence of affective disorders in Turkey among a representative sample of Turkish population. Methods: This study was conducted as a part of the "The Epidemiology of Childhood Psychopathology in Turkey" (EPICPAT-T) Study, which was designed by the Turkish Association of Child and Adolescent Mental Health. The inclusion criterion was being a student between the second and fourth grades in the schools assigned as study centers. The assessment tools used were the K-SADS-PL, and a sociodemographic form that was designed by the authors. Impairment was assessed via a 3 point-Likert type scale independently rated by a parent and a teacher. Results: A total of 5842 participants were included in the analyses. The prevalence of affective disorders was 2.5 % without considering impairment and 1.6 % when impairment was taken into account. In our sample, the diagnosis of bipolar disorder was lacking, thus depressive disorders constituted all the cases. Among depressive disorders with impairment, major depressive disorder (MDD) (prevalence of 1.06%) was the most common, followed by dysthymia (prevalence of 0.2%), adjustment disorder with depressive features (prevalence of 0.17%), and depressive disorder-NOS (prevalence of 0.14%). There were no statistically significant gender differences for depression. Maternal psychopathology and paternal physical illness were predictors of affective disorders with pervasive impairment. Conclusion: MDD was the most common depressive disorder among Turkish children in this nationwide epidemiological study. This highlights the severe nature of depression and the importance of early interventions. Populations with maternal psychopathology and paternal physical illness may be the most appropriate targets for interventions to prevent and treat depression in children and adolescents