• Carbon letters
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• v.15 no.1
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• pp.25-31
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• 2014

A microstructure analysis is carried out to optimize the process parameters of a randomly oriented discrete length hybrid carbon fiber reinforced carbon matrix composite. The composite is fabricated by moulding of a slurry into a preform, followed by hot-pressing and carbonization. Heating rates of 0.1, 0.2, 0.3, 0.5, 1, and $3.3^{\circ}C/min$ and pressures of 5, 10, 15, and 20 MPa are applied during hot-pressing. Matrix precursor to reinforcement weight ratios of 70:30, 50:50, and 30:70 are also considered. A microstructure analysis of the carbon/carbon compacts is performed for each variant. Higher heating rates give bloated compacts whereas low heating rates give bloating-free, fine microstructure compacts. The compacts fabricated at higher pressure have displayed side oozing of molten pitch and discrete length carbon fibers. The microstructure of the compacts fabricated at low pressure shows a lack of densification. The compacts with low matrix precursor to reinforcement weight ratios have insufficient bonding agent to bind the reinforcement whereas the higher matrix precursor to reinforcement weight ratio results in a plaster-like structure. Based on the microstructure analysis, a heating rate of $0.2^{\circ}C/min$, pressure of 15 MPa, and a matrix precursor to reinforcement ratio of 50:50 are found to be optimum w.r.t attaining bloating-free densification and processing time.

• Macromolecular Research
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• v.11 no.4
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• pp.260-266
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• 2003

Ethylene vinyl acetate (EVA)/clay nanocomposites were synthesized by blending a solution of ethylene vinyl acetate copolymer containing 12% vinyl acetate abbreviated as EVA-12 in toluene and dispersion of dodecyl ammonium ion intercalated montmorillonite (l2Me-MMT) in N,N-dimethyl acetamide (DMAc). X-ray patterns of sodium montmorillonite ($Na^+$-MMT) and 12Me-MMT exhibited $d_{001}$ peak at $2{\theta}=7.4^{\circ}$ and $2{\theta}=5.6^{\circ}$ respectively; that is, the interlayer spacing of MMT increased by about 0.39 nm due to intercalation of dodecyl ammonium ions. The XRD trace of EVA showed no peak in the angular range of $3-10^{\circ}(2{\theta})$. In the XRD patterns of EVA/clay hybrids with clay content up to 6 wt% the basal reflection peak of 12Me-MMT was absent. leading to the formation of delaminated configuration of the composites. When the 12Me-MMT content was 8 wt% in the EVA-12 matrix, the hybrid revealed a peak at about $2{\theta}=5.6^{\circ}$, owing to the aggregation of aluminosilicate layers. Transmission electron microscopic photograph exhibited that an average size of 12-15 nm clay layers were randomly and homogeneously dispersed in the polymer matrix, which led to the formation of nanocomposite with delaminated configuration. The formation of delaminated nanocomposites was manifested through the enhancement of mechanical properties and thermal stability, e.g. tensile strength of an hybrid containing only 2 wt% 12Me-MMT was enhanced by about 36% as compared with neat EVA-12.

• Journal of Microbiology and Biotechnology
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• v.21 no.9
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• pp.947-953
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• 2011

A fungal strain, Aspergillus terreus strain GA2, isolated from an agricultural field cultivating sweet sorghum, produced feruloyl esterase using maize bran. In order to obtain maximum yields of feruloyl esterase, the solid state fermentation (SSF) conditions for enzyme production were standardized. Effective feruloyl esterase production was observed with maize bran as substrate followed by wheat bran, coconut husk, and rice husk among the tested agro-waste crop residues. Optimum particle size of 0.71-0.3 mm and moisture content of 80% favored enzyme production. Moreover, optimum feruloyl esterase production was observed at pH 6.0 and a temperature of $30^{\circ}C$. Supplementation of potato starch (0.6%) as the carbon source and casein (1%) as the nitrogen source favored enzyme production. Furthermore, the culture produced the enzyme after 7 days of incubation when the C:N ratio was 5. Optimization of the SSF conditions revealed that maximum enzyme activity (1,162 U/gds) was observed after 7 days in a production medium of 80% moisture content and pH 6.0 containing 16 g maize bran [25% (w/v)] of particle size of 0.71-0.3 mm, 0.6% potato starch, 3.0% casein, and 64 ml of formulated basal salt solution. Overall, the enzyme production was enhanced by 3.2-fold as compared with un-optimized conditions.

• Korean Journal of Remote Sensing
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• v.26 no.2
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• pp.175-188
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• 2010

A new correction method is required for the Geostationary Ocean Color Imager (GOCI), which is the world's first ocean color observing sensor in geostationary orbit. In this paper we introduce a new method of atmospheric and the Bidirectional Reflectance Distribution Function(BRDF) correction for GOCI. The Spectral Shape Matching Method(SSMM) and the Sun Glint Correction Algorithm(SGCA) were developed for atmospheric correction, and BRDF correction was improved using Inherent Optical Property(IOP) data. Each method was applied to the Sea-Viewing Wide Field-of-view Sensor(SeaWiFS) images obtained in the Korean sea area. More accurate estimates of chlorophyll concentrations could be possible in the turbid coastal waters as well as areas severely affected by aerosols.

• Asian Spine Journal
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• v.12 no.6
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• pp.981-986
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• 2018

Study Design: Retrospective case series. Purpose: Cauda equina syndrome (CES) is associated with etiologies such as lumbar disc herniation (LDH) and lumbar canal stenosis (LCS). CES has a prevalence of 2% among patients with LDH and exhibits variable outcomes, even with early surgery. Few studies have explored the factors influencing the prognosis in terms of bladder function. Therefore, we aimed to assess the factors contributing to bladder recovery and propose a simplified bladder recovery classification. Overview of Literature: Few reports have described the prognostic clinical factors for bladder recovery following CES. Moreover, limited data are available regarding a meaningful bladder recovery status classification useful in clinical settings. Methods: A single-center retrospective study was conducted (April 2012 to April 2015). Patients with CES secondary to LDH or LCS were included. The retrieved data were evaluated for variables such as demographics, symptom duration, neurological symptoms, bladder symptoms, and surgery duration. The variable bladder function outcome during discharge and at follow-up was recorded. All subjects were followed up for at least 2 years. A simplified bladder recovery classification was proposed. Statistical analyses were performed to study the correlation between patient variables and bladder function outcome. Results: Overall, 39 patients were included in the study. Majority of the subjects were males (79.8%) with an average age of 44.4 years. CES secondary to LDH was most commonly seen (89.7%). Perianal sensation (PAS) showed a significant correlation with neurological recovery. In the absence of PAS, bladder function did not recover. Voluntary anal contraction (VAC) was affected in all study subjects. Conclusions: Intactness of PAS was the only significant prognostic variable. Decreased or absent VAC was the most sensitive diagnostic marker of CES. We also proposed a simplified bladder recovery classification for recovery prognosis.

• Progress in Superconductivity and Cryogenics
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• v.20 no.4
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• pp.11-15
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• 2018

Torque tubes in High Temperature Superconducting (HTS) motor transfer torque from superconducting field winding rotor to the room temperature shaft. It should have minimum heat conduction property for minimizing the load on cryo-refrigerator. Generally, these torque tubes are made with stainless steel material because of high strength, very low outgassing and low thermal contraction properties at cryogenic temperatures and vacuum conditions. With recent developments in composite materials, these torque tubes could be made of composites such as Kevlar and S-Glass, which have the required properties like high strength and low thermal conductivity at cryogenic temperatures, but with a reduced weight. Development and testing of torque tubes made of these composites for HTS motor are taken up at Bharat Heavy Electricals Limited (BHEL), Hyderabad in collaboration with Central Institute of Plastics and Engineering Technology (CIPET), Chennai and Indian Institute of Technology (IIT), Kharagpur. As these materials are subjected to vacuum, it is important to measure their outgassing rates under vacuum conditions before manufacturing prototype torque tubes. The present study focusses on the outgassing characteristics of Kevlar and S-Glass, using an Outgassing Measurement System (OMS), developed at IIT Kharagpur. The OMS facility works under vacuum environment, in which the test samples are exposed to vacuum conditions over a sufficient period of time. The outgassing measurements for the composite samples were obtained using pressure-rise technique. These studies are useful to quantify the outgassing rate of composite materials under vacuum conditions and to suggest them for manufacturing composite torque tubes used in HTS motors.

• Journal of Fashion Business
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• v.28 no.1
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• pp.36-50
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• 2024

This study aims to explore the potential of integrating traditional Indian motifs into modern textile design that appeals to the MZ generation. The objective is to create patterns that reflect the rich cultural tapestry of India while aligning with contemporary sensibilities. To achieve this, the design process includes a comprehensive literature review on the historical background, symbolism, and structure of Indian textiles and a survey to determine if the developed design suits the preferences of the MZ generation. Digital design tools such as TexPro, Photoshop, and Illustrator were used to create the designs based on the theme 'Cosmic Dream,' with sub-themes inspired by nature and Indian symbolism. 'Blooming Cosmos' focused on the structural beauty of the lotus, combined with paisley and rangoli patterns, for a vintage yet modern appeal. 'Cosmos in Blossom' is drawn from the rangoli technique of using varied materials, resulting in a romantic pastel-themed pattern that aligns with the 2023 Youth Trend. 'Cosmic Peacock' presented a lively ethnic pattern by merging simplified lotus motifs with India's national bird, peacock along with a paisley backdrop. A questionnaire was conducted to check the MZ consumer responses, and the most preferred design was the peacock and rangoli mixed design, ground colored in cream. These findings indicate the potential of the developed ethnic designs to be used for various purposes. By combining traditional motifs of India with modern elements, this study proposes ethnic textile designs that are suitable for MZ generation consumers.

• The Journal of Fisheries Business Administration
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• v.41 no.1
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• pp.73-91
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• 2010

The objective of this study is to examine the hedging effectiveness of shrimp futures market. Hedging effectiveness is measured by OLS model based on rolling windows. Analysis data are obtained from Kansai Commodities Exchange in Osaka and are weekly data of frozen shrimp futures and cash prices in the time period from July 9, 2003, to May 9, 2007. The empirical results are summarized as follows:First, the correlation coefficients between the nearby futures price changes and the cash(16/20) price changes are very low and have range from 0.141 to 0.208 values. Second, the minimum variance hedge ratios($\hat{\beta}$) are all statistically different from 0 at the 5% level and range from 0.0477 to 0.5039 values excluding Indian shrimps(26/30). Ex post hedging effectiveness, as measured by the coefficient of determination, $R^2$, is relatively very low and range from a low of 0.4% for west-south Indian shrimps(26/30) to a high 4.3% for Vietnamese shrimps(16/20). Third, ex ante hedging effectiveness, as measured by out-of-sample hedging period, is also very low and range from a low of -4.4% for west-south Indian shrimps(21/25) to a high of 3.4% for Vietnamese shrimps(16/20). This indicates that the shrimp futures market doesn't behave as risk management instrument of shrimp spot.

• Carbon letters
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• v.19
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• pp.57-65
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• 2016

Isroaniso matrix precursor synthesized from commercially available petroleum pitch was stabilized in air. The influence of oxygen mass gain during stabilization on the yield of matrix precursor was studied. Additionally, the influence of pressure on the yield of the stabilized matrix precursor in a real system was studied. The fourier transform infrared spectrometry (FTIR), thermogravimetric analysis (TGA), yield, yield rate, and yield impact were used to check the effect of stabilization and pressure on the yield of the matrix precursor and the end properties of the composite thereafter. The results showed that the yield increased with stabilization duration up to 20 h whereas it decreased for stabilization duration beyond 20 h. Further results showed that the stabilized matrix precursor for a duration of 5 h could withstand almost two-fold greater hot-pressing pressure without resulting in exudation as compared to that of a 1 h stabilized matrix precursor. The enhanced hot-pressing pressure significantly improved the yield of the matrix precursor. As a consequence, the densification and mechanical properties were increased significantly. Further, the matrix precursor stabilized for a duration of 20 h or more failed to provide proper and uniform binding of the reinforcement.

• Journal of Microbiology
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• v.44 no.1
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• pp.113-120
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• 2006

Candida tropicalis was treated with ultraviolet (UV) rays, and the mutants obtained were screened for xylitol production. One of the mutants, the UV1 produced 0.81g of xylitol per gram of xylose. This was further mutated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), and the mutants obtained were screened for xylitol production. One of the mutants (CT-OMV5) produced 0.85g/g of xylitol from xylose. Xylitol production improved to 0.87 g/g of xylose with this strain when the production medium was supplemented with urea. The CT-OMV5 mutant strain differs by 12 tests when compared to the wild-type Candida tropicalis strain. The XR activity was higher in mutant CT-OMV5. The distinct difference between the mutant and wild-type strain is the presence of numerous chlamvdospores in the mutant. In this investigation, we have demonstrated that mutagenesis was successful in generating a superior xylitol-producing strain, CT-OMV5, and uncovered distinctive biochemical and physiological characteristics of the wild-type and mutant strain, CT-OMV5.