Understanding the microstructure, mineralogical and adsorption characteristics of guar gum blended soil as a liner material

Production cost savings by lowering basis weight has been a trend in papermaking. The strategy has been to decrease the amount of softwood kraft pulp and increase use of fillers and recycled fibers. These changes have a tendency to lower strength properties of both the wet and dry web. To compensate for the strength loss in the paper, a greater quantity of strength additives is often required, either dosed at the wet end or applied to the wet web by spray. In this pilot-scale study, it was shown how strength additives can be effectively applied with foam-based application technology. The technology can simultaneously increase dryness after wet pressing and enhance dry and wet web strength properties. Foam application of polyvinyl alcohol (PVA), ethylene vinyl alcohol (EVOH), carboxymethyl cellulose (CMC), guar gum, starch, and cellulose microfibrils (CMF) increased web dryness after wet pressing up to 5.2%-units compared to the reference sample. The enhanced dewatering with starch, guar gum, and CMF was detected with a bulk increase. Additionally, a significant increase in z-directional tensile strength of dry web and and in-plane tensile strength properties of wet web was obtained. Based on the results, foam application technology can be a very useful technology for several applications in the paper industry.

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Adsorption Characteristics of 2,4-DNP on Bamboo-Based Activated Carbone

International Academy of Engineers Feb. 8-9, 2015 Kuala Lumpur (Malaysia) ◽

10.15242/iae.iae0215408 ◽

2015 ◽

Keyword(s):

Adsorption Characteristics

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Adsorption Characteristics of Carbon Sorbents from Naturally Oxidised Barzas Coal

Chemistry for Sustainable Development ◽

10.15372/csd20170605 ◽

2017 ◽

Keyword(s):

Carbon Sorbents ◽

Adsorption Characteristics

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Study of moisture adsorption characteristics of gingerbreads and biscuits using a hygrometric method

Acta Alimentaria ◽

10.1556/aalim.36.2007.3.3 ◽

2007 ◽

Vol 36 (3) ◽

pp. 311-320

Author(s):

L. Červenka ◽

S. Řezková ◽

J. Hejdrychová ◽

J. Královský ◽

I. Brožková ◽

...

Keyword(s):

Moisture Adsorption ◽

Adsorption Characteristics

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Formulation and Evaluation of Microbially- triggered tablets of Valdecoxib

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.v2i1.8841 ◽

2010 ◽

Vol 2 (1) ◽

Author(s):

Surender Verma ◽

S. Singh ◽

D. Mishra ◽

Atul Gupta ◽

Rakesh Sharma

Keyword(s):

Phosphate Buffer ◽

Guar Gum ◽

Oral Route ◽

Matrix Tablets ◽

In Vitro Dissolution ◽

Wet Granulation ◽

Dissolution Study ◽

Caecal Content ◽

Model Drug

The objective of present study was to develop colon targeted drug delivery using bacterially triggered approach through oral route. Valdecoxib (COX-2 inhibitor) was chosen as a model drug in order to target it to colon which may prove useful in inflammatory bowel disease and related disorders. Matrix tablets of Valdecoxib were prepared by wet granulation technique utilizing different ratio of Guar gum and Sodium starch glycholate. The prepared matrix tablets were evaluated for uniformity of weight, uniformity of content, hardness and in vitro dissolution study in simulated gastric and intestinal fluid (Phosphate Buffer pH-1.2, pH-6.8 and pH-7.4), followed by Dissolution study in bio-relevant dissolution media Phosphate Buffer (pH-6.8) containing rat caecal content. The results revealed that the formulated batch had released lesser quantity of drug at pH 1.2 and pH 7.4 in 2 hors whereas in biorelevent dissolution media containing rat caecal content it released significantly higher amount of drug which was also significantly higher than the dissolution media of same pH without caecal content (microflora) and it was concluded that guar gum can be used as a potential carrier for targeting drugs to colon.

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pH Dependent Release Potential of Natural Polymers in Sustained Release of Ornidazole From Colon Targeted Delivery System)

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.9.2.4 ◽

2019 ◽

Vol 9 (02) ◽

Author(s):

Sharma Pankaj ◽

Tailang Mukul

Keyword(s):

Drug Release ◽

Delivery System ◽

Targeted Delivery ◽

Guar Gum ◽

Acidic Environment ◽

Natural Polymers ◽

Weight Variation ◽

Curve Determination ◽

Preformulation Studies

The aim of present work was to prepare colon specific delivery system of Ornidazole using different ratio of shellac, zein and guar gum. From study of various literature it revealed that shellac, zein and guar gum released drug from dosage form at the pH of 6.9, 11.5, 7-9 respectively. The main problem associated with colon targeted drug delivery system is degradation of drug in the acidic environment of stomach to circumvent the present problem different combinations of shellac, zein and guar gum were employed in the formulation of colon targeted tablet. Several preformulation parameters were determined such as melting point, FTIR spectroscopy, preparation of calibration curve, determination of λmax and partition coefficient. After the preformulation studies, next steps were preparation of core tablets, evaluation of core of tablets and coating of tablets. The data obtained from preformulation study seven formulations were developed and evaluated for various parameters. Based on evaluated parameter such as weight variation, friability, dissolution study, invitro drug release etc. the F7 formulation show better results colon targeted tablets. Drug content in F7 formulation was 95% and drug release after 6 hrs was 96%. Formulation containing combination of shellac, zein and guar gum released least amount of drug in the acidic environment of stomach and released most of the drug in colon. It is evide

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Ru Passivated and Ru Doped e-TaN surfaces as Combined Barrier and Liner Material for Copper Interconnects: A First Principles Study

10.26434/chemrxiv.7427867 ◽

2018 ◽

Author(s):

Suresh Natarajan ◽

Cara-Lena Nies ◽

Michael Nolan

Keyword(s):

First Principles ◽

Film Growth ◽

Early Stage ◽

Copper Interconnects ◽

Liner Material ◽

Critical Dimensions ◽

Industry Standard ◽

Cu Film ◽

Improved Performance ◽

And Diffusion

<div>As the critical dimensions of transistors continue to be scaled down to facilitate improved performance and device speeds, new ultrathin materials that combine diffusion barrier and seed/liner properties are needed for copper interconnects at these length scales. Ideally, to facilitate coating of high aspect ratio structures, this alternative barrier+liner material should only consist of one or as few layers as possible. We studied TaN, the current industry standard for Cu diffusion barriers, and Ru, which is a</div><div>suitable liner material for Cu electroplating, to explore how combining these two materials in a barrier+liner material influences the adsorption of Cu atoms in the early stage of Cu film growth. To this end, we carried out first-principles simulations of the adsorption and diffusion of Cu adatoms at Ru-passivated and Ru-doped e-TaN(1 1 0) surfaces. For comparison, we also studied the behaviour of Cu and Ru adatoms at the low index surfaces of e-TaN, as well as the interaction of Cu adatoms with the (0 0 1) surface of hexagonal Ru. Our results confirm the barrier and liner properties of TaN and Ru, respectively while also highlighting the weaknesses of both materials. Ru passivated TaN was found to have improved binding with Cu adatoms as compared to the bare TaN and Ru surfaces.</div><div>On the other hand, the energetic barrier for Cu diffusion at Ru passivated TaN surface was lower than at the bare TaN surface which can promote Cu agglomeration. For Ru-doped TaN however, a decrease in Cu binding energy was found in addition to favourable migration of the Cu adatoms toward the doped Ru atom and unfavourable migration away from it or into the bulk. This suggests that Ru doping sites in the TaN surface can act as nucleation points for Cu growth with high migration barrier preventing agglomeration and allow electroplating of Cu. Therefore Ru-doped TaN is proposed as a candidate for a combined barrier+liner material with reduced thickness.</div>

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Colon targeting oral matrix tablets of mesalamine: Design, development and invitro evaluation

International Journal of Novel Trends in Pharmaceutical Sciences ◽

10.26452/ijntps.v10i1.1144 ◽

2020 ◽

Vol 10 (1) ◽

pp. 18-27

Author(s):

Audinarayana N ◽

Anala Srinivasulu ◽

Vellore Sruthikumari ◽

Likitha ◽

Ananda Deepak V

Keyword(s):

Drug Release ◽

Guar Gum ◽

Stability Study ◽

Matrix Tablets ◽

Drug Dissolution ◽

Matrix Tablet ◽

Cellulose Acetate Phthalate ◽

Design Development ◽

Release Pattern ◽

The Matrix

The principle in this present research is to formulate Mesalamine containing colon targeted tablets by using different polymers and evaluate the effect of different polymers in drug release pattern. The matrix tablets of Mesalamine are formulated by polysaccharides based polymers like Cellulose acetate phthalate (CAP), Ethyl cellulose (EC), Guar gum (GG) and Xanthan gum (XG) which protects the drug to release in Stomach and Small Intestine. The invitro drug dissolution investigation of F2 (GG and XG) Matrix tablet was controlled by swelling into a viscous gel in colonic pH, which have been accomplished as the best tablet. The optimized tablet F2 was found to be stable in stability study (short term) with reproducible evaluation data, which also shows the highest swelling index, increased viscosity in colonic pH. The drug release pattern from the F2 formulation follows swelling and erosion behavior. From the data it show that F2 tablets suitable for providing colon targeted drug delivery.

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