Search

Use the search bar or filters below to find any TAPPI product or publication.

Showing 171–180 of 1,680 results (Duration : 0.011 seconds)
Journal articles
Open Access
1998 tappi salary survey, TAPPI JOURNAL, August 1999, Vol. 82(8)

1998 tappi salary survey, TAPPI JOURNAL, August 1999, Vol. 82(8)

Journal articles
Magazine articles
Open Access
The Shendye-Fleming OBA Index for paper and paperboard, TAPPI Journal March 2022

ABSTRACT: We are proposing a new one-dimensional scale to calculate the effects of optical brightening agents (OBA) on the bluish appearance of paper. This index is separate from brightness and whiteness indices.In the paper industry, one-dimensional scales are widely used for determining optical properties of paper and paperboard. Whiteness, tint, brightness, yellowness, and opacity are the most common optical properties of paper and paperboard. Most of the papers have a blue cast generated by addition of OBA or blue dyes. This blue cast is given because of the human perception that bluer is whiter, up to a certain limit. To quantify this effect, it is necessary to determine how much blue cast paper and paperboard have. As the printing industry follows the ISO 3664 Standard for viewing, which has a D50 light source, this also plays a very important role in showing a blue cast. Color perception is based on light source and light reflected from an object. The ultraviolet (UV) component in D50 interacts with OBA to provide a reflection in the blue region of the visible spectrum. Use of a UV blocking filter results in measurements without the effect of emission in the blue region. This difference is used in determining the OBA effect in the visible range of the paper. This equation is known as the Shendye-Fleming OBA Index.

Journal articles
Magazine articles
Open Access
Evaluation of rice straw for purification of lovastatin, TAPPI Journal November 2021

ABSTRACT: Cholesterol synthesis in the human body can be catalyzed by the coenzyme HMG-CoA reductase, and lovastatin, a key enzyme inhibitor, can reduce hypercholesterolemia. Lovastatin can be obtained as a secondary metabolite of Aspergillus terreus ATCC 20542. In this study, rice straw of lignocellulose was used in aeration and agitation bath fermentation in a 1-L flask, and a maximal crude extraction rate of 473 mg/L lovastatin was obtained. The crude extract was treated with silica gel (230•400 mesh) column chromatography. Ethyl acetate/ethanol (95%) was used as the mobile phase, and isolation was performed through elution with various ethyl acetate/ethanol ratios. The highest production rate of 153 mg/L was achieved with ethyl acetate/ethanol in a ratio of 8:2. The lovastatin gained from the crude extract was added to 12 fractions treated with 0.001 N alkali, and acetone was then added. After 24 h of recrystallization at 4°C, the extract underwent high-performance liquid chromatography. The purity had increased from 25% to 84.6%, and the recovery rate was 65.2%.

Journal articles
Open Access
Color Gamut-A New Tool for the Pressroom?, TAPPI JOURNAL February 2009

Color Gamut-A New Tool for the Pressroom?, TAPPI JOURNAL February 2009

Journal articles
Open Access
Formulating to enhance the radiation cross linking of thermoplastic rubber for the hot-melt pressure-senstivie adhesives, June 1988, TAPPI Journal 88JUN155

Formulating to enhance the radiation crosslinking of thermoplastic rubber for hot-melt pressure-sensitive adhesives, TAPPI JOURNAL June 1988

Journal articles
Open Access
Ethylene-carbon monoxide extrudable adhesive copolymers for polyvinylidene chloride, June 1988, TAPPI Journal 88JUN140

Ethylene-carbon monoxide extrudable adhesive copolymers for polyvinylidene chloride, TAPPI JOURNAL June 1988

Journal articles
Open Access
Techniques for expanding the sphere of statistical process control, TAPPI JOURNAL July 1988

Techniques for expanding the sphere of statistical process control, TAPPI JOURNAL July 1988

Journal articles
Open Access
Steambox Comparator Experiments: Apparatus Validation and In

Steambox Comparator Experiments: Apparatus Validation and Investigation of Steambox Performance, 1999 Engineering Conference Proceedings

Journal articles
Magazine articles
Open Access
Editorial: Agility and adaptation in a dynamic business world, TAPPI Journal January 2021

ABSTRACT: Being agile and adaptive in this current business world is both necessary and beneficial. Throughout last year, we all continued to both directly and indirectly experience the dynamic world where we live. As we wll know, in early 2020 the pandemic gained momentum and has fundamentally altered our daily lives, both personally in how we live and professionally in how we work.

Journal articles
Magazine articles
Open Access
Probing the molecular weights of sweetgum and pine kraft lignin fractions, TAPPI Journal June 2021

ABSTRACT: The present investigation undertook a systematic investigation of the molecular weight (MW) of kraft lignins throughout the pulping process to establish a correlation between MW and lignin recovery at different extents of the kraft pulping process. The evaluation of MW is crucial for lignin characterization and utilization, since it is known to influence the kinetics of lignin reactivity and its resultant physico-chemical properties. Sweetgum and pine lignins precipitated from black liquor at different pHs (9.5 and 2.5) and different extents of kraft pulping (30•150 min) were the subject of this effort. Gel permeation chromatography (GPC) was used to determine the number average molecular weight (Mn), mass average molecular weight (Mw), and polydispersity of the lignin samples. It was shown that the MW of lignins from both feedstocks follow gel degradation theory; that is, at the onset of the kraft pulping process low molecular weight-lignins were obtained, and as pulping progressed, the molecular weight peaked and subsequently decreased. An important finding was that acetobromination was shown to be a more effective derivatization technique for carbohydrates containing lignins than acetylation, the technique typically used for derivatization of lignin.