Kaolin

Study Design. Retrospective case control study.Objective. To evaluate the hemostatic benefits of using a kaolin impregnated dressing during pediatric spinal deformity correction surgery.Summary of Background Data. Minimizing blood loss and transfusions are clear benefits for patient safety. A technique common in both severe trauma and combat medicine that has not been reported in the spine literature is wound packing with a kaolin impregnated haemostatic dressing.Methods. Estimated blood loss and transfusion amounts were analyzed in a total of 117 retrospectively identified cases. The control group included 65 patients (46F, 19M, 12.7±4.5 years, 10.2± 4.8 levels fused) who received standard operative care with gauze packing between June 2007 and March 2010. The treatment group included 52 patients (33F, 19M, 13.9±3.2 years, 10.4 ± 4.3 levels fused) who underwent intra-operative packing with QuikClot Trauma Pads (QCTP, Z-Medica Corporation) for all surgeries from July 2010 to August ...

To evaluate, using conventional in vitro procedures, the abrasivity, enamel polishing properties, and stain removal effectiveness of various commercial dentifrices that have a variety of compositions and are marketed for cleaning, whitening, and/or polishing capabilities, and to examine their relationships between stain removal and abrasivity. The Relative Dentin Abrasivity (RDA) method was used to measure abrasivity, and the Pellicle Cleaning Ratio (PCR) procedure was used to evaluate stain removal performance. A Cleaning Efficiency Index (CEI) was calculated using the RDA and PCR values. Enamel polish was determined on bovine enamel specimens using a reflectometer. All treatments were performed on a V-8 cross-brushing machine using aqueous dentifrice slurries and standard nylon-bristle toothbrushes. A total of 26 dentifrices, purchased at retail, were tested against the American Dental Association (ADA) calcium pyrophosphate reference standard. All dentifrices removed extrinsic st...

Microwave-initiated synthesis of polyacrylamide-grafted sodium alginate, a graft copolymer with wide variety of applications has been reported in this study. The effect of reaction parameters (i.e., irradiation time and monomer concentration) onto the percentage grafting has been investigated. The resulting polymer has been characterized by a variety of characterization techniques such as intrinsic viscosity measurement, Fourier transform infrared spectra, 13C NMR spectra, elemental analysis, thermogravimetric analysis, molecular weight determination using static light scattering analysis, and scanning electron micrographs. Further, the flocculation efficiency of this graft copolymer has been investigated in coal suspension. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

A mathematical model is presented for estimating compressive strength of high-strength concrete incorporating pozzolanic materials, based on the strength of a control ordinary Portland cement (OPC) concrete made with similar mixture characteristics and curing history. In this study, metakaolin (MK) and silica fume (SF) were used as cement replacement materials at 5%, 10%, and 15% by mass. Water/cementitious materials (w/cm) ratios varied from 0.27 to 0.33, and strength testing was conducted up to an age of 180 days. It was found that the strength of a pozzolanic mixture could be related to the strength of its equivalent control by a linear function. Key parameters involved in the model are the pozzolanic and dilution factors, which can be correlated to the pozzolan content in the mixture. The study concludes that the accuracy of the model increases with concrete age. At ages 28 days and above, 97% of the estimated strengths are within ±5% of the actual value.

Industrial grade Kaolin deposits in Sri Lanka are located in Boralesgamuwa and Meetiyagoda. Two distinct grades of Kaolin are produced at Meetiyagoda refinery, based on the whiteness index (WI). The presence of iron oxides significantly affects the WI of the Kaolin. Upgrading of the whiteness will result in a huge increase in the product prices as high as 35%. However, no effective methods are currently in place for the whiteness improvement at Meetiyagoda Kaolin refinery. Hence, this study was carried out to assess the whiteness enhancement capability of Meetiyagoda Kaolin by chemical leaching process using oxalic and citric acids. The treatment time (0–120 min) in steps and concentration of acids (0.01, 0.1, 0.2, 0.3, 0.4 and 0.5 M) were considered as the main variables of this study. Leachate and treated samples were analysed by using spectrophotometric and XRF methods respectively. The results depict that the oxalic acid is more effective in leaching iron oxides from Kaolin compared to citric acid for the Kaolin at Meetiyagoda. It was observed that 25% and 14% of Fe in Kaolin filter cakes can be removed by 0.4 M oxalic and 0.5 M citric acid respectively, within a treatment time of 120 mins at the room temperature.

This study is to collect information regarding major metallogenic aspects of Kaolin deposits with certain commercial possibilities in the northeastern part of Bolivar state. This article describes the geological, physicochemical and genesis of kaolin deposits that developed in an economically significant in geological provinces of the Guayana Shield. A portion of these Kaolin deposits have been exploited in the region of Upata and Km 88 in the 1990s for the production of refractory and ceramic products, however, there are many deposits of Kaolin with geo-economic potential that currently do not known geological reserves and commercial quality. It describes the main physicochemical characteristics of kaolin and its most striking applications.

The demand and use of concrete have led to a lot of research in improving its
strength, durability, life cycle, temperature effect and many more. Improving the
strength and durability of concrete is very paramount in the construction of basic
infrastructure in a bid to make it sustainable. The choice of metakaolin as a
supplementary material in improving the mechanical strength and durability of
concrete is espoused in this review. This was done in a bid to reduce the cost of
cement being one of the most expensive component of concrete production and to also
improve sustainability in the construction industry. The review revealed that the use of
metakaolin in the production of concrete showed an improved mechanical strength.
Literatures revealed that up to 10%-20% increase in mechanical strength is recorded
with the use of metakaolin in concrete production. Additionally, the durability
properties of concrete with metakaolin also improved. However, the review revealed
that incorporating metakaolin in concrete production reduced the workability of
concrete and increased the heat of hydration. The result of this review showed that the
use of metakaolin reduced the cost of producing concrete. Based on the uniqueness of
the material, it is recommended for use in countries where it is abundant in a bid to
promote sustainability in concrete technology, improve mechanical strength and
reduce cost.

The effectiveness and efficacy of flotation diminishes with the size of the particles. However, the kaolin industry is unique in successfully using flotation with fine particle size feed. Kaolin is valued as a white pigment and therefore the goal in kaolin flotation circuits is to remove the colored impurities to result in an acceptable brightness product. Kaolin flotation originated with a novel carrier flotation process and later on carrierless flotation techniques were developed. The surfactants that are utilized to impart selectivity are based on fatty acids. The purpose of this paper is to provide a comprehensive review of the reagent schemes used in the kaolin industry, the understanding of which has been significantly aided by research work conducted in Prof. Somasundaran's lab. C 2002 Elsevier Science (USA)

ÖZ
Türkiye’de çıkan kırmızı kil yataklarından en önemlilerinden ikisi Nevşehir ilinin Avanos ilçesinde ve
Bilecik ilinin Pazaryeri ilçesine bağlı Kınık Köyünde bulunmaktadır. Avanos ve Kınık killerinin ortak özelliği; bu killerde demir oksit (%Fe2O3) oranının, %7’nin üzerinde olmasıdır. Bu çalışmanın amacı ise, saf kaolinin olmadığı durumlarda, sır reçetesine Avanos ve Kınık kırmızı killerinin eklenmesinin sırda yaratacağı artistik değişikliklerin belirlenmesidir. Bu doğrultuda, Avanos ve Kınık killerinin eklendiği ham sır karışımları, şamotlu kil, kırmızı çömlek kili ve döküm kilinden oluşan tabletlere akıtma yoluyla uygulanmıştır. Ayrıca kıyaslama yapmak amacıyla, Avanos ve Kınık killeri yerine saf Avanos kaolini ham sırlara aynı oranda ilave edilmiş ve aynı yüzeyler üzerine uygulanmıştır. Bunlara ek olarak, demir oksit kaynağı olarak düşünülen Avanos ve Kınık killeri; aventurin, krakle ve parlak transparan sır bileşimlerine ilave edilerek ek denemeler yapılmıştır. 1050 derecede fırınlanan sır kompozisyonlarının bünyeyle uyumu, sırın yüzeye tutunması, renkleri, parlak-matlık özellikleri ve estetik durumu incelenmiştir. Sonuç olarak, saf kaolinin olmadığı durumlarda çömlekçi kili olarak kullanılan Avanos ve Kınık killerinin sır karışımında kaolin görevi görebileceği ve sırda küçük çaplı renk değişimleri ve artistik etkiler yarattığı gözlemlenmiştir.

ABSTRACT
Avanos, as a town located in Nevşehir and Kınık village in Pazaryeri, Bilecik, are among the most prominent well-known red clay deposits in Turkey. The common characteristic specific to these both sites is the fact that the percentage of iron oxide (%Fe2O3) in clays extracted from Avanos and Kınık deposits is above 7 (seven). Within this study, it was aimed to examine the changes and artistic effects occurring after the red clays from Avanos and Kınık deposits were added to glaze as colorant, in the absence of pure kaolin. Along with this aim, Avanos and Kınık clays were added to raw glaze compositions, and this blend was applied to tablets made through the proportioned mixture of chamotte clay (fireclay), red earth pottery clay and casting clay. In addition to that, pure Avanos kaolin was added at the same amount to raw glaze composition instead of Avanos and Kınık clays and this composition
was applied to the tablets as well, produced through the use of same clays in order to obtain comparative results. Furthermore, additional tests were conducted by adding Avanos and Kınık clays as iron-oxide source to the blend of aventurine glaze, glossy crackle glaze and transparent glaze. Glaze compositions applied to tabled were fired at 1050 Celsius degrees, and the effects were examined carefully in terms of glaze fit, compatibility between glaze and clay body, glaze colours, the degree of being matte and glossy and aesthetics. The results indicated that Avanos and Kınık clays, used as the pottery clay in the absence of pure kaolin, could be utilized as substitute of kaolin, and the addition of these clays to glaze compositions lead to small-scale colour changes and artistic effects.

Limbah tahu berasal dari buangan atau sisa pengolahan kedele menjadi tahu yang terbuang karena tidak terbentuk dengan baik menjadi tahu sehingga tidak dapat dikonsumsi.
Proses pengelolaan limbah padat sebelum pengolahan juga tidak jauh berbeda, setiap ampas yang dihasilkan dari proses penyaringan ditampung dalam sak (karung) atau ember, kemudian dijual ke pelanggan dengan harga Rp2.500/ember atau Rp7.000/sak.
Kondisi optimum pengadsorpsi dari limbah tahu mengadsorpsi logam Cr dan Fe dalam limbah air lindi TPA adalah pada berat 1000 mg dan waktu kontak 150 menit. Kemampuan maksimum adsorben dari limbah tahu mengadsorpsi krom dalam limbah air lindi TPA sebesar 100% dan besi sebesar 95,53%, sedangkan kemampuan maksimum limbah tahu dalam mengadsorpsi logam kadmiun tidak diperoleh.

Lightweight geopolymer is a new innovation in concrete industry. It has an advantage because it could act as geopolymer as well as lightweight concrete. It is environmentally friendly since it is not produced with Portland cement which normally emit CO2 gas, a major contributor of greenhouse gases and global warming in the atmosphere. The material used in this experimental study are precursors, fine aggregates, alkaline activator solutions, superplasticizers, and foam. The precursors used were fly ash and kaolin, in which the percentage of kaolin were 0%, 5%, 10%, 15%, and 20% of the weight of fly ash. The concentration of NaOH at 12M and 14M. The results from the flow table test revealed that the optimum diameter of the mixture was 25.28 cm, which was found when the percentage of kaolin was 0% and the concentration of NaOH was 12M. The results of setting time showed that the fastest initial and final setting time of the mixture were 245 and 360 minutes respectively, also discovered when the percentage of kaolin was 0% and 12M NaOH. In addition, the optimum compressive strength of the mixture was 19.20 MPa, discovered when the density was 1481.12 kg/m 3 , percentage of kaolin was 0% and at 14M NaOH. Then, the microstructure analysis of the mixture showed that increasing the concentration of NaOH without adding kaolin produced a dense geopolymer matrix with very small pores, however, when kaolin is increasingly added to the mixture, it produced a less dense matrix with large pores. In conclusion, mixtures without kaolin resulted in lightweight geopolymer with better properties and characteristics.

Impregnation of a polyurethane sponge with kaolin, feldspar, silica, fusible glass slurry followed by temperature treatment in air in the temperature range 800-1000 0 C leads to the formation of aluminosilicate ceramics with a set pore size. The low-temperature synthesis of porous ceramics is based on the stage-by-stage formation of low-temperature eutectics and thermodestruction of polyurethane sponge.

In this paper we have investigated the potential of garlic and turmeric extracts, at 0.25%, 0.5%, concentrations and Trichoderma harzianum and combination of Trichoderma harzianum with kaolin @ 4gm/kg to enhancing the seed germination of maize and soybean. The seed germination under control ranged up to 82%, where treatments enhanced up to 98% germination. We have observed 97% seed germination in maize seeds treated with Trichoderma
harzianum with 1 gm kaolin and 98% seed germination in soybean seeds treated with Trichoderma harzianum. 0.25% extracts of garlic and 0.5% extracts of turmeric showed 93% germination and 68% field emergence of seedling in soybean respectively. On the basis of present results, the garlic (0.25%) and turmeric (0.5%) extracts, Trichoderma harzianum and combination of Trichoderma harzianum with kaolin, can be used for the enhancement of seed
germination of various crops.