Introduction. Occasionally over exposure or over development makes processed radiographs too dark, By Reducing (Bleaching) such a radiograph whit a Reducing solution the dentist can enhance the image with low diagnostic value. Methods. Mandible of a dry skull with posterior teeth, double films pocket, intera oral radiography unit, diluted solution of fixer and developer, Coppor sulfate reducer solution, automatic processing unit. A radiograph was prepared with normal exposure time from posterior region of mandibule and saved as positive control. A series of double film pocket were exposed to obtian overexposed radiographs. One film from each pocket was used as the negative control and the other was reduced by copper sulfate solution. The diagnostic quality of reduced radiographs were evaluatel in three steps: 1. By clinical evaluation of reduced radiographs. 2. By densitometry of reduced radiographs. 3. By evaluation the number of steps wedges.Results. The diagnostic quality and resolution of reduced Radiographs were increased and their contrast was decreased.Discussion. Copper sulfate Reducing agent is very good solution for improving diagnostic quality of very dark radiograph and prevent reexposure of the patient.

In this research work, the reductive leaching of pyrolusite in a sulfuric acid medium with the aid of orange peel as a reductant was investigated. The important parameters affecting the leaching process include temperature in the range of 25 to 95 °C, the weight ratio of Reducing agent to pyrolusite (R/P) in the range of 0 to 2 (w/w), and the concentration of sulfuric acid in the range of 0.05 to 0.25 M. According to the results, the parameters of temperature and the R/P are more significant in the reductive leaching process. With increasing temperature from 25 to 95 °C, Mn recovery increases from 0.5% to 52.5%. Also Mn recovery with a two-step increase in 0-0.1 and 0.1-1.5 of the R/P indicates a jump of 28.5% and 19.0%, respectively. Sulfuric acid concentration shows its effect by supplying sulfate and hydrogen ions in the leaching process. The successful use of orange peel as a reductant was confirmed by achieving a manganese dissolution efficiency of 98.1% under optimum conditions (temperature of 90 °C, sulfuric acid concentration of 0.1 M, and R/P ratio of 1.5 (w/w)). Kinetic investigations showed that the shrinking core model could not be used to determine the leaching mechanism of pyrolusite in the presence of fruit peel reductant. Avrami's kinetic model with very high fitting accuracy was used to determine the kinetic model of pyrolusite leaching.

Recently, plasmonic nanoparticles with unique optical properties have been used in nanomedicine ranging from optical biosensing to bioimaging to drug delivery. Meanwhile, gold nanoparticles with very small and uniform size are desirable for these applications due to their low toxicity. In this project, reduction of gold by sodium borohydride (NaBH4) led to preparation of metal nanoparticles anchored gelatin matrix successfully. Due to its high biocompatibility, gelatin is very suitable as a stabilizing agent and despite other organic capping agents, it reduces the toxicity of these Au nanoparticles (Au Nps). These nanomaterials have been studied using Fourier transformed infrared (FT-IR), Optical Absorption, Photoluminescence (PL) spectroscopy techniques, using transmission electron microscope (TEM) and X ray diffraction (XRD). And influence of different concentrations of Reducing agent have been investigated in preparation and optical properties of Au Nanoparticles with Gelatin as a capping agent. These nanomaterials are very promising for making devices with high luminosity in nano dimensions. In addition, since non -toxic and solvent materials are used in synthesis, the integration of these particles into a variety of systems, especially those related to biological and biomedical applications, can be practical and useful.

Ferroalloys are compounds of iron with other elements that have many applications in various industries. The production of ferroalloys is usually done in electric arc furnaces and by the carbothermic process. In this method, metal oxides are reduced by different carbon materials, and the type of carbon material used can affect the way the process is carried out and the quality of the product. Metallurgical coke is the most common Reducing agent in the production of ferroalloys, but due to its increasing shortage, high price, and relatively high content of harmful impurities, manufacturers are looking for other options. Charcoal has less ash than other carbon materials, but due to environmental problems, its use is not common. Coal with the highest reactivity is not considered among the main options due to its high sulfur content and low compressive strength. Recently, semi-coke, which is prepared at a lower temperature than coke, has gained attention in the ferroalloys industry due to its unique characteristics (high fixed carbon, high specific resistance, high chemical activity, low ash, and low sulfur). Semi-coke improves the quality of ferroalloy and reduces energy consumption and production costs. So far, semi-coke has been used in the process of iron and ferroalloy production in a limited way, and their results show the advantages of the presence of semi-coke. Therefore, in this research, the carbon materials used in the production of ferroalloys, the advantages of semi-coke, and the production method of semi-coke are discussed.

Purpose: Because of over exposure or over development, occasionally radiographs will be darkened. For lightening and better diagnostic quality of radiographs, bleaching agents are used. One of the super proportional reducers is used in this research. The objective of this investigation was to determine the effect of Reducing agent on diagnostic quality of extra oral darked radiograph.Methods & Materials: In this experiment, a human skull was used for radiographic examination. Two extraoral films were put in one casselle as double film. After exposure the two films were processed. One of the radiographs was used as control and the other film lmdergone bleaching procedure get light. The bleaching time was recorded, then films were washed in water. They were put in diluted developing solution (1/20 diluted). The suitable color was selected by examiner. The time was recorded. Radiographs were washed in water, then they were put in diluted fixing solution (1/20 diluted). They were washed and dried, and ready to interpret. 43 double film were used in this experiment. Radiologists and surgeon to evaluate diagnostic quality of definitive landmarks in sample and control films. They should give a grade from 1 to 5 for each chosen landmark on sample and control Radiographs.Grade 1 for the worst diagnostic quality.Grade 5 for the best diagnostic quality.The data were statistically studied to determine if there is a significant difference between the diagnostic quality of the control and sample film.Results: According to wilcoxon test, there is meaningful different between the diagnostic quality of the controls and sample films.Conclusion: To improve diagnostic quality of extraoral darked radiographs we can use a super proportional Reducing agent such as copper surface solution. This solution not only causes the reduction of density of darked radiographs but also it cause improvement of its diagnostic quality. The concentration of solution used for extraoral Radiograph is different from one that we use for intra oral radiograph.

To address the environmental concerns, a relatively simple, innovative and low-cost procedure has been suggested for synthesis of graphene nanosheets (GNSs). The procedure utilized here for synthesizing GNSs is derived from aqueous suspension of graphene oxide (GO). Ficus carica (FC) is known to be remarkable antioxidant. It is regarded as suitable biocompatible alternative to hazardous and toxic chemicals. This method ensures non-hazardous nature of the deoxygenating agent (FC) as well as their oxidized outcomes. Structural and morphological characterization indicates the absence of oxygen-bearing groups from graphene oxide. Characterization was done by standard techniques such as X-ray crystallography, FTIR, RAMAN, DLS, and UV– Vis spectrophotometry. Morphological investigation of resulting material was also undertaken through standard techniques by FESEM, TEM, HRTEM with SAED pattern. Thermal stability of FC derived graphene was also investigated. The investigation may initiate new routes for preparing GNSs at large scale facilitating a better research and commercial utilization.

In the present work, different concentrations of citrate (Reducing agent) were used to reduce the silver precursor, and Poly Vinyl Alcohol (PVA) was used as a capping agent. The electrochemical performance of the synthesized multivalent silver oxide (AgxO)/PVA nanocomposite has been carefully examined. The well-crystalline, spherical, and aggregate-free AgxO/PVA nanocomposite was synthesized. The present findings were strengthened by structural, elemental, and morphological studies. The AgxO/PVA nanocomposite showed Surface Plasmon Resonance (SPR) and defect-related band gap mechanisms. The two oxidoreduction peaks in the cyclic voltammogram were observed for the graphite electrode coated with the as-prepared samples. The AgxO/PVA-loaded electrodes showed a maximum specific capacitance of 269 Fg-1 at a scan rate of 10 mVs-1. It was observed that the citrate can be used to produce silver oxide nanoparticles and to improve the electrochemical functionality of the silver oxide nanoparticles blended with PVA. There are potential uses for this type of nanocomposite-coated electrode in supercapacitors and high-performance energy storage systems.

The unstable chloroaluminum borohydride is stabilized on polyvinylpyridine, and it is used as an efficient and regenerable polymer supported transition-metal borohydride reagent for reduction of variety of organic compounds such as, aldehydes, ketones, acid chlorides, epoxides and azides. The reagent is unable to reduce, esters, amides, oximes, and nitro compounds.

Background: Developing effective methods for the synthesis of bio-compatible and non-toxic nanoparticles is the main goal of nanotechnology. In the most chemical methods, a chemical Reducing agent is used to reduce metal ions. But, in chemical methods, the stability of nanoparticles is controversial and synthesis in large sizes is much more difficult. Moreover, there is an increasing demand for the synthesis of nanoparticles using eco-friendly methods in order to avoid the harmful effects of chemical factors. Green synthesis is an alternative method for this purpose. The aim of this study was to assess green synthesis of silver nanoparticles using Mentha aquatic L extract as the Reducing agent.Methods: In this Study, Mentha aquatic L was used as a Reducing agent for the synthesis of bio-compatible silver nanoparticles. Green synthesis of silver nanoparticles was performed in three phases: preparing Mentha aquatic L extract, preparing silver nitrate solution, and adding the extract to the silver nitrate solution. Morphology of the sample and particle size distribution was analyzed by scanning electron microscopy (SEM) and dynamic light scattering (DLS), respectively. Light absorption of nanoparticles was analyzed by Ultraviolet - visible (UV-Vis) absorption spectroscopy.Results: Analysis of UV-Vis absorption at 430 nm indicated the surface plasmon resonance (SPR) property of the particles. Considering the peak of dynamic light scattering (DLS) plot, particle size distribution of silver nanoparticles was below 100 nm. According to the results of scanning electron microscopy (SEM), nanoparticles with mean particle size of 30 nm and spherical shape were the most frequent particles. The Energy-dispersive X-ray spectroscopy (EDX) confirmed the presence of silver.Conclusion: Based on the results, proper synthesis of nanoparticles with uniform distribution was confirmed. Therefore, Mentha aquatic L extract is an effective Reducing agent that can be used as an alternative for chemical products in the synthesis of nanoparticles.