Dry impregnation in fluidized bed: Drying and calcination effect on nanoparticles dispersion and location in a porous support

The synthesis of metal nanoparticles dispersed inside the grains of a porous inorganic support was carried out by ‘‘dry impregnation’’ in a fluidized bed. The principle of this technique consists in the spraying of a solution containing a metal source into a hot fluidized bed of porous particles. The metal source can be of different nature such as metal salts, organometallic precursors or colloidal solutions. The experimental results obtained from iron oxide deposition on a porous silica gel as support, constitute the core of this article but others results concerning the deposition of rhodium from a colloidal suspension containing preformed rhodium nanoparticles are also described. More precisely, this study aims to understand the effect of the bed temperature during the impregnation step, the initial particle porosity and the calcination operating protocol on the metallic nanoparticles dispersion and location in the silica porous particles. The so-obtained products were characterized by various techniques in order to determine their morphology, their surface properties and the dispersion of the nanoparticles inside the support. The results showed that, under the chosen operating conditions, the deposit efficiency is close to 100% and the competition between the drying rate, depending on the process-related variables, and the capillary penetration rate, depending on the physicochemical-related variables, controls the deposit location. A quasi uniform deposit inside the support particles is observed for soft drying. The metal nanoparticles size is controlled by the pore mean diameter of the support as well as the calcination operating protocol

Synthesis of Supported Catalysts by Dry Impregnation in Fluidized Bed

The synthesis of catalytic or not composite materials by dry impregnation in fluidized bed is described. This process can be carried out under mild conditions from solutions of organometallic precursors or colloidal solutions of preformed nanoparticles giving rise to reproducible metallic nanoparticles containing composite materials with a high reproducibility. The adequate choice of the reaction conditions makes possible to deposit uniformly the metal precursor within the porous matrix or on the support surface. When the ratio between the drying time and the capillary penetration time (tsec/tcap) is higher than 10, the impregnation under soft drying conditions leads to a homogeneous deposit inside the pores of the particles of support. The efficiency of the metal deposition is close to 100%, and the size of the formed metal nanoparticles is controlled by the pores diameter. Finally, some of the presented composite materials have been tested as catalysts: iron-based materials were used in carbon-nanotubes synthesis, while Pd and Rh composite materials have been investigated in hydrogenation reactions

Frequency of errors in nursing and associated factors in the cases referred to the Mortality Committee in Shahrekord University of Medical Sciences during 2006-2012

زمینه و هدف: شناسایی خطاهای پرستاری و ارتقاء امنیت بیماران امری حیاتی است. با توجه به اینکه خطا در عرصه ارائه خدمات پرستاری، پدیده ای آسیب رسان و در برخی موارد غیرقابل جبران است، لذا این مطالعه با هدف تعیین فراوانی خطاهای پرستاری و فاکتورهای مرتبط با آن در پرونده های ارجاعی به کمیته مرگ و میر انجام شد. روش بررسی: در این مطالعه توصیفی، کلیه پرونده های ارجاعی به کمیته مرگ و میر استان چهارمحال و بختیاری مورد بررسی قرار گرفت و از پرونده هایی که پرستار به عنوان مقصر شناخته شده بود اطلاعاتی شامل: سن و جنس، نوع بستری، محل ارجاع، بخش بستری و علت بستری بیمار وجنس، سنوات خدمت، بخش محل خدمت، مقطع تحصیلی، شیفت کاری پرستار و نوع خطای مرتکب شده توسط پرستار مورد بررسی قرار گرفت. داده ها با استفاده از آمار توصیفی(فراوانی) و تحلیلی(آزمون دقیق فیشر) مورد تجزیه و تحلیل قرار گرفت. یافته ها: از 400 پرونده های ارجاعی به کمیته مرگ و میر دانشگاه علوم پزشکی شهرکرد از سال 1385 تا نیمه اول سال 1391 حدود 50 خطای پرستاری روی داده که 44 آن ها مربوط به عدم اطلاع به موقع به پزشک و 36 درصد مربوط به مشکلات در ثبت گزارش پرستاری بود. نتیجه گیری: با توجه به اینکه از بین بردن خطاهای کاری به صورت صد در صد امکان پذیر نمی باشد، بنابراین با کاهش حجم کاری، افزایش تعداد پرستار، سیستم نظارتی دقیق و آموزش تا حدودی می توان میزان خطاهای پرستاری را کاهش داد

The relation between the quality of life and restless legs syndrome in patients undergoing hemodialysisis dialysis centers in ChaharMahal and Bakhtiari, 2011

Aims: The chronic renal failure and the subsequent hemodialysis and its consequent problems such as restless legs syndrome affect the individual’s quality of life through the changes they cause in his life style and health status. The present study was conducted to investigate the association between the quality of life and restless legs syndrome in hemodialysis patients. Materials and Methods: In this descriptive –analytical study, 171patients who were undergoing to hemodialysis at hospitals of ChaharMahal and Bakhtiariprovenanceselected via census sampling. The subjectsdivided into two groups; one suffering from the restless legs syndrome and the other without syndrome. Data was collected using WHO-QOL BREF quality of life questionnaire andrestless legs syndromequestionnaire, then it was analyzed by the software SPSS 15 and independent statistical t-test. Findings: The findings revealed that 98(57.3%) out of 171 hemodialysispatients, who were studied, suffered from restless legs syndrome and 73(%42.7) subjects were without syndrome. The average age in the group suffering the syndrome was 59.27± 16.86 and in the group without syndrome was 55.20±17.95.However thedifferencebetween the average age in both groups was not statistically significant (p= 0.131).The average quality of life in the group suffering the syndrome was 32.82±8.53and in the group without the syndrome was 39± 14.57. This difference was statistically significant (p<0.05). Conclusion: regarding the result of the study, the average quality of life in hemodialysispatients is low. Patients suffering from restless legs syndrome also have lower quality of life. Therefore it is recommended that the quality of life of these patients be improved through taking appropriate measures and presenting requisite interferences

Characterizing and correcting for the effect of sensor noise in the dynamic mode decomposition

Dynamic mode decomposition (DMD) provides a practical means of extracting insightful dynamical information from fluids datasets. Like any data processing technique, DMD's usefulness is limited by its ability to extract real and accurate dynamical features from noise-corrupted data. Here we show analytically that DMD is biased to sensor noise, and quantify how this bias depends on the size and noise level of the data. We present three modifications to DMD that can be used to remove this bias: (i) a direct correction of the identified bias using known noise properties, (ii) combining the results of performing DMD forwards and backwards in time, and (iii) a total least-squares-inspired algorithm. We discuss the relative merits of each algorithm, and demonstrate the performance of these modifications on a range of synthetic, numerical, and experimental datasets. We further compare our modified DMD algorithms with other variants proposed in recent literature

The Impact of Education, Based on the BASNEF Model, on Maternal Attitudes toward Child Abuse in Shahrekord Health Centers, 2012

Background As childhood is considered to be the infrastructure for growth and progress, experiencing misconduct may leave behind a heritage of imbalance and unrest which may be manifested in any situation in some form of mental disorder (neurotic attack). This problem leads to physical and mental disorder in children and inflicts heavy social and economic damages to the society. This research aims at evaluating the impact of education, based on BASNEF model, on maternal attitude towards child abuse. Methods The current research is based on an interventional study on 95 mothers referred to the Shahrekord health center. They were randomly selected and divided into two groups of test and control, and education was conducted in four sessions based on structures of BASNEF model. Finally their obtained information was analyzed using paired t-test, independent t-test, Mann-Whitney and Chi-square statistical tests. Results The mean score in beliefs was 77.73±7.27, attitudes 87.01±8.1, subjective norms 85.55±8.4 and enabling factors 82.77±10.64 in the test group. There was a significant difference in the average marks of the structures of the BASNEF model (beliefs, attitudes, subjective norms, and enabling factors) between the control and intervention groups after the training process Conclusion Model-based training has a positive effect on improving attitudes; therefore, instead of traditional methods, applying a planned training program is suggested so that its effects can be reliable

Modelling and experimental validation of a fluidized bed reactor freeboard region: application to natural gas combustion

A theoretical and experimental study of natural gas-air mixture combustion in a fluidized bed of sand particles is presented. The operating temperatures are lower than a critical temperature of 800 °C above which the combustion occurs in the vicinity of the fluidized bed. Our study focusses on the freeboard zone where most of the methane combustion takes place at such temperatures. Experimental results show the essential role of the projection zone in determining the global thermal efficiency of the reactor. The dense bed temperature, the fluidizing velocity and the mean particle diameter significantly affect the thermal behaviours. A model for natural gas-air mixture combustion in fluidized beds is proposed, counting for interactions between dense and dilute regions of the reactor [Pré et al. (1998)] supplemented with the freeboard region modelling of Kunii-Levenspiel (1990). Thermal exchanges due to the convection between gas and particles, and due to the conduction and radiation phenomena between the gas-particle suspension and the reactor walls are counted. The kinetic scheme for the methane conversion is that proposed by Dryer and Glassman (1973). Model predictions are in good agreement with the measurements

Optimization of UV/H2 O2 /Fe3 O4 process to remove aniline from aqueous solutions using central composite methodology

Aniline with a benzene ring in its structure is a toxic, carcinogenic and mutagenic compound that causes many diseases in humans. Various methods have been developed to remove this pollutant from the environment among which the advanced oxidation has been successful in obtaining higher aniline removal efficiency. In this study, a UV light and Fe3O4 nano catalyst were used to remove aniline. In this study, the efficiency of aniline removal was studied as a dependent variable and aniline, hydrogen peroxide and iron nano catalyst concentrations, time and pH were investigated as independent variables. The concentration of aniline was measured by spectrophotometer. The optimization of the process was determined using the response surface method design and the central composite design model. Design Expert software was used to analyze the data. The results showed that the aniline removal efficiency decreased with increase in nano-catalyst concentration, hydrogen peroxide concentration and time and decreased with increasing pH and aniline concentration. To achieve maximum efficiency (78.1%), the optimal values for pH; initial concentration; time; nanoparticle content and H2O2 content were 3.2; 101 mg L–1; 50 min; 0.45 g L–1 and 31.08 mmol L–1. The results showed that the photo-Fenton process has a desirable ability to remove aniline from aqueous solution at pilot scale. Therefore, it was suggested to study the efficiency of this process as one of the clean and environmentally friendly methods at full scale on real wastewate