Low Quality Fibers Research Articles

Molecular characterization of the ligninolytic Sundarban mangrove isolate Stenotrophomonas maltophilia GD1 and its promising applications in the dye and fiber industry

Lignocellulolytic biocatalysts, including laccase, cellulase, and pectinase, have high potential for degrading lignocellulosic biomass (LCB). Jute and banana are fiber-producing LCBs that hold significant economic value. Nevertheless, certain parts of these plants are utilized as waste material due to their low-quality fiber, which causes losses for the industry. These waste portions can be processed and biologically converted into high-value fiber. A bacterial strain called Stenotrophomonas maltophilia GD1, which can produce several proteins, was isolated from the Sundarban mangrove ecosystem in West Bengal, India, and genetically analyzed via 16S rRNA sequencing. The strain exhibited the ability to produce all three necessary lignocellulolytic enzymes, with the highest levels of laccase and minimal cellulase and pectinase activity. The strain modified the fibers extensively, as determined by Young’s modulus, and removed the color from the toxic industrial dyes. This demonstrates the broad potential of this strain for waste valorization and environmental remediation. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) confirmed the enhanced fiber quality. Microbial phylogenetic relationships were established using Molecular Evolutionary Genetics Analysis version 11 (MEGA 11).

Amphoteric dry strength chemistry approach to deal with low-quality fiber and difficult wet-end chemistry conditions in the Asian and North American markets

With Japan’s high recycling rates and low access to fresh fiber sources, reaching strength targets in manufacturing packaging materials is a challenge. Declining quality of recycled fiber and minimal freshwater consumption results in difficult wet-end chemistry conditions in terms of high conductivity and elevated levels of dissolved and colloidal substances (DCS). These trends are somewhat typical of other Asian regions. Due to global trade, Asian packaging materials have become a part of the North American (NA) raw material pool. The gradual closing of mill water circuits for fresh water and energy savings results in more difficult wet-end chemistry conditions experienced in North America. China’s ban on the import of mixed paper and the consequent ban on all waste-paper imports triggered a significant price drop in recycled raw material, resulting in plans for increased manufacturing capacity in North America. Between increased demand, decreasing fiber quality, and movement towards more closed white water systems associated with packaging grade paperboard (even a virgin fiber mill uses a fair amount of recycled fiber), new methods to overcome strength reduction in raw materials must be proactively considered for North America. Reviewing the strategies currently used in the Asian industry regarding strength development is an excellent starting place for NA producers. A clear difference between Asian and NA wet-end chemistry is the dominant position of amphoteric dry strength agents. This paper reviews the fundamentals of dry strength development that explain the trend towards the increased application of amphoteric dry strength technology for poor-quality fiber and highly contaminated water circuits in Asian markets. This paper discusses the development and application performance of the novel 4th generation amphoteric polyacrylamide (AmPAM) dry strength technology, based on selected laboratory and mill case studies.

Isolation and Characterization of Cellulose Nanocrystals from Rejected Fibers Originated in the Kraft Pulping Process.

In the final process of the bleached kraft pulp there are some cellulose fibers that are separated from the main fibers stream; these fibers are rejected and considered as a low quality fibers, these fibers are known as rejected fiber (RF). In the present work the potential use of these fibers for Cellulose Nanocrystals (CNCs) synthesis was studied. The physical and chemical properties of synthesized CNCs were characterized through different techniques such as Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), and Thermogravimetric Analysis (TGA). Results demonstrate the feasibility of CNCs synthesis with a yield of 28.1% and 36.9%, and crystallinity of 73.5% and 82.7%. Finally, the morphology and synthesis conditions suggest that this industrial reject fiber (RF) could be used as a source for the CNCs production, thus adding value to the kraft process and opening new possibilities for innovation in the pulp industry.

The reinforcement mechanism of bacterial cellulose on paper made from woody and non-woody fiber sources

To protect forest resources and increase the value of agro-industrial residues, it would be helpful to produce paper-based materials from non-woody or recycled fiber resources. This study investigated the reinforcement mechanism of bacterial cellulose (BC) on paper sheets made from different sources including softwood, hardwood, sugarcane bagasse, bamboo, wheat straw, and recycled fiber, which represent a selection of high quality, medium quality, and low quality fibers. The results showed that by maintaining BC addition at a low level of 0.5–1.5% (total paper dry weight), the paper sheets made from high and medium quality fibers have the maximum tensile index improvement, with 5–25%. The tensile index of low quality fiber including wheat straw pulp and recycled fiber pulp increased slightly and gradually with the level of BC addition; at 5% BC addition, the tensile indexes increased by 9 and 40%, respectively. To investigate the BC reinforcement mechanism, different fiber characteristics, SEM images of BC reinforced paper, BC retention rate on paper, and the effects of dispersant addition were evaluated. It was found that high BC addition or retention rate in paper sheets do not necessarily result in good BC reinforcement effects but that proper dispersion of BC is important.

English

Fiber availability is not always ensured in all year long grazing systems. In this context, low quality fiber feeds may be of relevance for bovine feeding. We propose, thus, to study the effect of adding 5% of urea (on a dry matter basis) on the chemical composition and nutritional value of Hedychium gardnerianum, Sheppard ex Ker-Gawl (ginger lily or Kahili ginger), a traditional fiber source used by Azorean farmers. Treatments were: green ginger lily as a control, addition of 5% urea on a DM basis to green ginger lily, with treatments lasting 0, 5, 10, 15 and 30 days and addition of 5% urea on a DM basis to previously dried ginger lily, at day 0. The treatment afforded a significant (P<0.05) increase in crude protein, while maintaining the neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents, and a variation in the acid detergent lignin (ADL) content. No significant improvement in in vitro dry matter digestibility. The treatment with urea of the green forage does not have the same effect as in other low quality fiber feeds, namely straw, since ginger lily has much higher a Crude Protein value than those other fibrous feeds. Key words: Hedychium gardnerianum, in vitro digestibility, urea treatment, roughage.

Fatores de risco, achados clínicos, laboratoriais e avaliação terapêutica em 36 bovinos com deslocamento de abomaso

A contínua seleção genética para maior produção de leite em conjunto com o aumento da capacidade digestiva e profundidade corporal aumentou a susceptibilidade à ocorrência de abomasopatias, incluindo o deslocamento do abomaso. Este trabalho objetivou realizar um estudo retrospectivo sobre o deslocamento de abomaso em 36 bovinos atendidos na Clínica de Bovinos, Campus Garanhuns da Universidade Federal Rural de Pernambuco, durante o período de janeiro de 2000 a fevereiro de 2009. Foram diagnosticados 27 casos de deslocamento do abomaso à direita, seis casos de deslocamento do abomaso à esquerda e três casos de vólvulo abomasal. Onze casos considerados moderados, sem grave distensão abdominal, apetite presente para a forragem e delimitação de som metálico até o 8º espaço intercostal, foram tratados clinicamente; enquanto 20 casos com distensão abdominal moderada a severa, associada a distúrbios sistêmicos, foram considerados graves e tratados cirurgicamente. Duas vacas foram eutanasiadas devido peritonite difusa ou alterações graves na serosa do abomaso, totalizando 18 animais submetidos ao tratamento cirúrgico. Dois animais foram encaminhados para abate e três vacas chegaram prostradas e morreram sem receber nenhum tratamento. A análise dos fatores de risco identificou a estação chuvosa como estatisticamente significativa. O maior número de deslocamento do abomaso ocorreu em vacas mestiças com 24 casos (66,6%), seguida por bovinos da raça Holandesa com 11 (30,5%) e Gir com um (2,9%) caso. A composição da alimentação oferecida variou bastante e caracterizou-se por conter excesso de carboidratos e, na maioria dos casos, fibra de baixa qualidade. Os sinais clínicos mais frequentes foram comportamento apático, desidratação, timpanismo ruminal leve a severo com motilidade ausente ou diminuída, som de líquido ao balotamento do flanco direito, som de chapinhar metálico e/ou observação de uma estrutura similar a uma víscera distendida no gradil costal do lado correspondente ao deslocamento; fezes liquefeitas, enegrecidas e de odor fétido. Os achados hematológicos revelaram, na maioria dos casos, leucocitose neutrofílica e hiperfibrinogenemia. Na análise do fluido ruminal havia comprometimento da dinâmica da flora e fauna microbiana, e elevação no teor de cloreto em 93,9% dos casos, com o índice médio alcançando 47,66 mEq/L. O índice de recuperação clínica e cirúrgica alcançou 100% e 72,2%, respectivamente. As condutas descritas são opções viáveis para o tratamento dos deslocamentos leves e severos, no entanto a prevenção permanece a melhor alternativa a ser adotada.

Compactação primária do abomaso em 14 bovinos no estado de Pernambuco

Apesar de forragens grosseiras e secas serem empregadas comumente na alimentação de vacas em várias regiões, especialmente durante o período seco, a compactação primária do abomaso tem sido pouco relatada no Brasil, provavelmente pela dificuldade de diagnóstico dos veterinários de campo. Este trabalho objetivou realizar um estudo retrospectivo sobre a compactação primária do abomaso em 14 bovinos no Estado de Pernambuco. Oito casos considerados moderados, sem grave distensão abdominal e sem compactação do rúmen, foram tratados conservativamente e quatro casos graves, com severa distensão abdominal e compactação do rúmen, foram tratados cirurgicamente. Um touro foi encaminhado para abate e uma vaca morreu antes de receber qualquer tratamento. O maior número de casos de compactação do abomaso ocorreu em bovinos da raça Holandesa com seis casos (42,9%), seguido por animais mestiços com cinco casos (35,8%) e as raças Pardo-Suiça, Nelore e Marchigiana com um caso cada (21,3%). A composição da alimentação oferecida caracterizou-se por conter fibra de baixa qualidade e variou bastante dentre os casos. Os sinais clínicos mais frequentes foram comportamento apático, desidratação, timpanismo ruminal associado à hipomotilidade, distensão abdominal, hipomotilidade intestinal e fezes escassas ou ausentes com presença de muco. Os achados hematológicos revelaram, na maioria dos casos, leucocitose por neutrofilia e hiperfibrinogenemia. Na análise do fluido ruminal havia comprometimento da dinâmica da flora e fauna microbiana, e elevação no teor de cloreto. O índice de recuperação clínica (4/8) e cirúrgica (2/4) observado neste estudo foi de 50%. As condutas clínica e cirúrgica permanecem como opções viáveis para o tratamento das compactações leves e severas, entretanto o prognóstico é considerado reservado, principalmente quando associado à gestação avançada.

Yield and fiber quality of Upland cotton as influenced by nitrogen and potassium nutrition

Nutrient stress in Upland cotton ( Gossypium hirsutum L.) depresses lint yield, particularly of late-season fruit (bolls), and may disrupt fiber development. A 2-year (1999 and 2000) study was conducted outdoors in large pots to determine individual effects of nitrogen (N) and potassium (K) stress at flowering stage on lint yield and fiber quality. Treatments were half-strength nutrient solution from emergence to crop maturity (control), 20% and 0% of control N from first flower onward, and 20% and 0% of control K from first flower onward in 1999 and first square onward in 2000. Leaf N and K were determined every 2–3 days from an uppermost, fully expanded leaf on the main-stem of five plants selected at random. Mature bolls were harvested from sympodial (fruiting) branches only and grouped according to week of anthesis across a 35-day flowering period, providing five flowering groups, from which fiber length, strength, and micronaire were determined. Fiber length was not consistently altered by stress, suggesting early stages of fiber development were indirectly affected by plant N and K status. Nitrogen deficiency decreased yield through early termination of reproductive growth. In 1999, although flowering group four of N-deficient cotton had low length, strength, and micronaire, values for weighted-sum micronaire (whole-plant micronaire) increased under N stress by about 12% in 0% N treatment and about 18% in 20% N treatment. In general, N and K stress had opposite effects on weighted-sum micronaire. The year by N treatment interaction was significant for weighted-sum strength, due to weak fibers in N-deficient cotton in 1999, but no treatment difference in 2000. Apparently, crop response to N stress was influenced by environment, as flowering groups with low quality fiber also comprised a large fraction of total lint, and thus placed heavy demands on plant N and carbohydrate reserves. Severe K deficiency in 2000 decreased yield and lint weight boll −1, and micronaire values of 3.7 or less were evident in flowering groups two, three and four. Results support evidence that N stress indirectly affects cotton growth, as N deficiency decreased fiber length, strength and micronaire primarily in flowering groups with large percentage of bolls. Results from 2000 support evidence that K deficiency adversely affects reproductive growth, boll weight, and sugar translocation in cotton.

Developing a Twist Draft Spinning System for Small-Scale Production of Special Material Yarns

This paper presents a new spinning system, a kind of twist draft spinning in which the withdrawal tension in a yam being spun out is used to control its count. This system produces the yam directly from a large mass of fibers in a pot, can spin even low quality fibers that are difficult to spin with modem spinning systems, and is able to keep up with small-scale production of functional yams made from special materials. The spinning process is analyzed and the relation between the yam properties and the fiber properties is revealed. This relation is a valuable tool for designing properties of yarns spun with twist draft spinning. Several functional yarns of a special material are also spun with this system.

Analysis of Graded Flax Fiber and Yarn by Pyrolysis Mass Spectrometry and Pyrolysis Gas Chromatography Mass Spectrometry

Pyrolysis mass spectrometry (PyMS) and pyrolysis gas chromatography mass spectrometry (PyGCMS) were used to analyze samples of flax fiber and yarn which had been graded as being of high, medium, and low quality. In-source, low-voltage PyMS spectra were quite similar overall. To identify potential quality markers, we screened mass responses with thresholds for the following criteria: (1) intensity, (2) repeatability, and (3) correlation to quality level. Chemical interpretation of the selected masses suggests the samples may be differentiated based on the levels of pectin, fatty acids, protein, and phenolics. PyGCMS of the graded flax fiber and yarn provided additional information about the identity of some of the selected mass responses. More palmitic acid was detected in the low-quality fiber and yarn samples. Sinapylaldehyde and sinapyl alcohol were present in higher concentrations in the low-quality yarn as compared to the high-quality material. These data suggest that the amounts of cuticular material and waxes are inversely related to quality in both flax fiber and yarn and may be used as markers for certain aspects of flax product quality. Keywords: Flax; pyrolysis mass spectrometry; quality measurements

Statistical Analysis of the Properties of Advanced Fibers Designed for Titanium Alloy and Intermetallic Reinforcement

ABSTRACTThe mechanical properties of new ceramic reinforcing fibers need to be well characterized before their incorporation into composite materials. Critical fiber properties include strength and Weibull modulus, both off the spool and after matrix extraction, bundle strength, modulus and creep resistance. Important composite properties include thermochemical stability, interface debond energy and interfacial sliding resistance. Tailoring these interfacial properties invariably involves the use of a fiber coating that can, in turn, influence fiber properties. Methods of measuring strength related properties are addressed and the results of a computer simulation to assess the quality of measured data using statistical methods are presented. The simulation was developed to determine the errors associated with a strength/Weibull modulus determination based on a limited number of samples. Finally, an assessment of the effect of mixing of high and low quality fiber on bundle strength and composite properties is made.