Reduction Discoloration of Reactive Dyed Cotton Waste and Chemical Recycling via Ionic Liquid

The textile industry generates large volumes of waste throughout its production process.Most of this waste is colored,therefore,discoloration is an important step toward recycling and reusing this waste.This study focused on the chemical reductive discoloration of textile waste composed of cotton dyed with reactive dye.The experimental design demonstrated the significant influence of the concentration of reducing agent and time of reaction on the degree of whiteness of the cotton fibers.The concentration of the alkaline agent was not significant in the process.The optimization of the reaction conditions lead to Berger degree of 50.5±3.5.The discolored cotton was chemically recycled through dissolution in ionic liquid 1-ethyl-3-methylimidazolium chloride and regeneration in film form in water.The microstructure of the regenerated cellulose films was evaluated by Scanning Electron Microscopy(SEM)indicating complete dissolution and uniform regeneration.The discoloration process reduced the polymerization degree and crystallinity index of the cotton fibers but retained the cellulose I structure.The dissolution and cellulose regeneration process results in transparent films with an amorphous structure.The thermal behavior,evaluated by thermogravimetric analysis,indicated that residues and regenerated film presented a main decomposition step.The maximum decomposition rate temperature of the regenerated films was approximately 40℃lower than the cotton fibers,which correlates well with the reduction in polymerization degree and amorphous structure.In general,the study demonstrated that textile cotton waste dyed with reactive dyes can be chemically discolored to form transparent and amorphous films,contributing to the development of sustainable strategies for the textile industry.

Discoloration Range and Shroud Image Depth Values Cannot Be Satisfied by the Same Proton Energy

The radiative hypothesis has been revisited showing other characteristics, produced by the protons used as dyes in total disagree with the ones of the Body Image that appears on the Shroud of Turin. Our investigations highlight that for the protons to reach 3.7 cm in air, the distance that measures the range of discoloration effects, must be emitted with an energy of about 1.5 MeV using Wilson and Brobeck’s empirical formula and 1.35 MeV using Bethe’s. This last formula provides a result closer to reality. Bethe shows that the penetration depth is greater than that calculated empirically. Such a value of proton energy (1.35 MeV) makes it possible to satisfy the discoloration effects range for the Shroud but it is incompatible with a depth of penetration in linen that is only 200 nm. Moreover, using the same subatomic particles, we obtained on the colored linen a distribution of energy represented by regression but not linear. Thus, also the possible I(z) correlation, between color intensity and body-sheet distance, which should be due to the oxidizing action of protons, does not agree with that extracted from the Shroud of Turin.

Discoloration of Congo Red by Rod-Plate Dielectric Barrier Discharge Processes at Atmospheric Pressure

A dielectric barrier discharge （DBD） reactor with a rod-plate electrode configuration was used for the oxidative decomposition of Congo red dye in an aqueous solution. Plasma was generated in the gas space above the water interface under atmospheric pressure. Discharge characteristics were analyzed by voltage-current waveforms. Effects of applied voltage, initial conductivity, and initial concentration were also analyzed. Congo red discoloration increased with increased applied voltage and decreased conductivity. The initial conductivity significantly influenced the Congo red discoloration. Under the same conditions, the highest discoloration rate was obtained at 25 mg/L. The presence of ferrous ions in the solutions had a substantial positive effect on Fenton dye degradation and flocculation. At an applied voltage of 20 kV, about 100% of dye was degraded after 4 min of Fe^2＋/DBD treatment. Results showed that adding a certain dosage of hydrogen peroxide to the wastewater could enhance the discoloration rate. Possible pathways of Congo red discoloration by DBD plasma were proposed based on GC/MS, FTIR, and UV-vis spectroscopy analyses.

Adsorptive Properties of Dyes to Cellulosic Sheet and Discoloration of Dye Solution by UV-ray Irradiation

The adsorptive properties and selectivity of dyes and water molecules to cellulosic sheet, dependence of adsorptive properties of dyes on the concentration of dye solution, and discoloration of the dye solution due to the UV-ray irradiation were determined for 18 kinds of commercial dyes. The results are as follows： 1） the adsorptive properties of dyes to cellulose sheet differed greatly, but did not depend on the dye types such as acidic, basic and so on; 2） adsorptive properties of dyes to cellulosic sheet de- pended on the concentration of dye solution and were classified into 4 types： concentration-independent, increasing or decreasing with dye concentration, and having a maximum. This classification was irrelevant to the dye types; 3） the irradiation of UV-ray did not cause significant discoloration of dye solution itself, which suggested that wood components as well as dye molecules influence the discoloration of wood.

Correlation of discoloration and biomechanical properties in porcine sclera induced by genipin

·AIM: To study the feasibility of using the discoloration to evaluate the biomechanical properties after treating with genipin.·METHODS: Porcine cadaver eyes were treated for30 min with 1.0%(by w/v) genipin. Untreated samples were used as controls. After treatment, scleral strips of4.0 ×10.0-mm2 were cut. The denaturation temperature(Td) measurement and stress-strain test were performed after taking photograph to analyze the color.·RESULTS: Within 24 h after treating with genipin, the sclera exhibited a bluish color which became deeper with time. And the denaturation temperature also was increased gradually. Compared with untreated groups, at1, 6, 12, 24 and 36 h after treatment, the ultimate stress were increased by 56%, 153%, 173%, 225% and 211%respectively. The Young’s modulus at 10% strain also increased by 170%, 246%, 264%, 389% and 288%respectively. There were strong correlation between the discoloration and the biomechanical properties(ΔE-Ultimate stress:R2=0.892, P =0.00; ΔE-Young’s modulus:R2=0.602, P =0.00).·CONCLUSION: Genipin could be used to strengthen collagen gradually in a relatively short time span. And the biomechanical properties could be reliably evaluated via simple visible discoloration.

Effect of drying methods on the discoloration of three major domestic softwood species in Korea

Japanese pine, Korean pine and larch are three major softwood species in Korea. Their colors are relatively light, thus easily discolored due to drying and UV irradiation. In this study, they were dried with five different drying methods, steam treated and exposed to weathering. Their colors were measured using a spectrophotometer and comparisons made both among species and drying methods. For Japanese and Korean pines, high temperature dried and steam-dried specimens showed distinct color differences compared with the controls. Steam treatment discolored the dried specimens of Japanese and Korean pines but did not discolor those of larch. After weathering for 144 days the specimens of Japanese pine showed slight color differences among drying methods.

Effects of gold plating on the resistance to high temperature discoloration of the cavity for ceramic packages

The effects of thickness and types of gold plating on the resistance to hightemperature discoloration of gold plating on cavity surface of ceramic package were investigated. Itwas found that the thicker gold plating, the less discoloration degree for ceramic packages.Non-cyanide gold plating performed better resistance to high-temperature aging than cyanide goldplating. The relationship between the gold plating thickness and the amount of diffused Ni to thegold plating of ceramic packages with Au/Ni and Au/Ni-Co platings after heating at 420℃ for 15 minwas also studied. When the gold plating thickness reach 2.0 μm and 1.6 μm for Au/Ni and Au/Ni-Coplating systems, respectively, no discoloration was observed on the gold plating surface of cavity,and the corresponding diffused Ni amounts (mass fraction) are 1.0% and 0.4%, while the diffused Coto the gold plating is 0.04%.

Evaluation of Teeth Discoloration Induced by Endomethasone, AH+, Canason and Apexit Paste

Objective: The aim of this study was to investigate, in vitro, the color changes of the teeth, induced by endodontic sealers. Materials and Methods: Forty-five mature maxillary and mandibular anterior teeth, extracted for periodontal reasons, were collected. After the chemo-mechanical instrumentation of the root canal, teeth were filled with four endodontic sealers (Endomethason, AH+, Canason and Apexit). Depending on canal sealers and the CEJ (Cement Enamel Junction), teeth were divided into 8 experimental groups (n = 5) and one control group/CG (n = 5). Teeth color changes (L*a*b*/CIE Commission Internationaled’ Eclaraige) were determinated by a spectrophotometer Vita Easyshade in 4 stages (Baseline, Week 0, 4 and 12). Results: Between the EOCEJ and CG for the parameter L*, there was a statistical significance (p 0.05). The L*a*b* results were: L* (83.6 ± 4.8 → 83.6 ± 4.9);a* (﹣2.68 ± 1.02 → ﹣1.12 ± 0.72) and b* (20.2 ± 4.5 → 24.4 ± 4.2). Conclusions: All endodontic sealers may cause teeth discoloration.

Effects of gold plating on the resistance to high temperature discoloration of the cavity for ceramic packages

The effects of thickness and types of gold plating on the resistance to high temperature discoloration of gold plating on cavity surface of ceramic package were investigated. It was found that the thicker gold plating, the less discoloration degree for ceramic packages. Non-cyanide gold plating performed better resistance to high-temperature aging than cyanide gold plating. The relationship between the gold plating thickness and the amount of diffused Ni to the gold plating of ceramic packages with Au/Ni and Au/Ni-Co platings after heating at 420℃for 15 min was also studied. When the gold plating thickness reach 2.0 μm and 1.6 μm for Au/Ni and Au/Ni-Co plating systems, respectively, no discoloration was observed on the gold plating surface of cavity, and the corresponding diffused Ni amounts (mass fraction) are 1.0% and 0.4%, while the diffused Co to the gold plating is 0.04%.

Discoloration on Methylene Blue Solutions by Direct and Catalytic Ozonation

During textile manufacturing, huge amounts of wastewaters characterized by removed impurities and high concentrations of dye are produced. These wastewaters cause several problems when they are discharged to the environment. The use of ozone in wastewater treatment results of interest. In this work we propose to assess the discoloration rate of different synthetic wastewaters as a function of pH, dye concentration (methylene blue (MB)) and reaction time. A comparison of discoloration rate between conventional ozonation and catalytic ozonation salts of copper, zinc, silver and nickel was also performed. For the optimization of the ozonation process of colored solutions, it was used a central composite experimental design with five replicates of the center point resulting to evaluate the influence of the independent variables at different ranges of pH, [MB] and time. In the catalyst-assisted ozonation, [MB], pH and the reaction time were fixed to 100 mg/L, 5.5 and 15 min, respectively. The optimized experimental conditions to provide maximum discoloration were pH=3.3;[MB]=8.6 mg/L and time=74.3 min. Regarding the catalyst-assisted ozonation, it was found that CuSO4 catalyst gave better color reduction if compared with other catalysts assayed.

Discoloration mechanism,structures and recent applications of thermochromic materials via different methods:A review

Thermochromic material is a kind of smart material whose color will vary as the result of the phase transition caused by the temperature change. The characteristics of thermochromic materials are the memory functions to the temperature, having great potential applications in aerospace, military, anticounterfeiting technology, construction and other fields. In recent years, many kinds of thermochromic materials have been prepared by different methods and their discoloration mechanisms are various according to published literatures. In this paper, the classification, discoloration mechanism, preparation methods, application fields and development trend of thermochromic materials are reviewed.

Discoloration of Rhodamine B dyeing wastewater by schorl-catalyzed Fenton-like reaction

As other natural iron-bearing minerals, schorl could be taken as an effective iron source for degradation of organic pollutants by mineral-catalyzed Fenton-like system. In our present study, the schorl-catalyzed Fenton-like system has been successfully developed for discoloration of an active commercial dye, Rhodamine B (RhB), in an aqueous solution. Through a number of batch discoloration experiments under various conditions, it was found that the reactivity of the system increased by, respectively, increasing schorl dosage, temperature, hydrogen peroxide starting concentration and by decreasing the pH. Over 90% of discoloration ratio could be gained in less than 30 min, and nearly 70% of total organic carbon (TOC) could be removed in less than 200 min. And, the schorl catalyst could be repeatedly used at least ten times, still with high catalytic activity. Comparative studies indicated that the RhB discoloration ratios were much higher in presence of schorl and H2O2 than those in presence of schorl or H2O2 only, which suggested that the schorl-catalyzed Fenton-like reaction governed the RhB discoloration process. The content of Fe ion leaching in the solution was also measured using inductively coupling plasma-atomic emission spectra (ICP-AES). A mechanism proposed herein suggested that adsorption and Fenton-like reaction (heterogeneous and homogeneous) were responsible for the discoloration of RhB.

Angle-dependent discoloration structures in wing scales of Morpho menelaus butterfly

The Morpho butterfly is famous for its typical structural color and has increasingly attracted the interest of scholars in a wide variety of research fields. Herein, it was found that the color of Morpho menelaus butterfly wings is not only structure-based but also viewing-angle-dependent. Firstly, the discoloration effect of this typical butterfly was confirmed by a series of experiments. Then, the general form, arrangements, and geometrical dimensions of the scales were observed using a stereomicroscope. Scanning electron microscopy was also used to examine the two-dimensional morphologies and structures of a single scale. Afterwards, one model with the optimized three-dimensional profile of the structure was described using Pro-engineer software. The associate model was then analyzed to reconstruct the process between the incident light and the model surface. Finally, the mechanism of the angle-dependent discoloration effect was analyzed by theoretical calculation and optical simulation. Different light propagation paths and the length of the incident light at different angles caused destructive or constructive interference between the light reflected from the different layers. The different spectra of the reflected light make the wings appear with different structural colors, thereby endowing the angle-dependent discoloration effect. The consistency of the calculation and simulation results confirms that these structures possess an excellent angle-dependent discoloration effect. This functional "biomimetic structure" would not only be of great scientific interest but could also have a great impact in a wide range of applications such as reflective displays, credit card security, and military stealth technology.

Dyeability of Chemically Treated Wood and its Discoloration by UV-ray Irradiation

The study illustrates differences between colors of poplar I-214 veneers dyed by reactive blue KN-R and 4 kinds of chemical reagents, and those of treated veneer exposed to UV-ray for 3 days. The results show there are some laws in poplar I-214 dyeing and UV-ray attenuation of each chemically treated veneer color. The chemical reaction carded out between cellulose or lignin on veneer surface and dye molecules when they met with. The capability of dyeing and discoloration of veneer is improved by control of dyeing technology, especially chemical treatments; being treated by acetylation and maleic anhydride protects dyed wood discoloration.

Role of schorl’s electrostatic field in discoloration of methyl orange wastewater using schorl as catalyst in the presence of H_2O_2

Dyeing wastewater containing methyl orange (MO) could be effectively discolored by schorl-catalyzed Fenton-like system. Experimental results indicated that the MO discoloration ratios could be increased by increasing schorl dosage, temperature, initial H2O2 concentration, and by decreasing solution pH. When the raw schorl and the schorl samples sintered at 750°C, 850°C, 950°C and 1050°C were used as catalyst in Fenton-like system, the MO discoloration ratios obtained were 82%, 31%, 30%, 31% and 7%, respectively. XRD results showed that samples sintered at 750°C, 850°C and 950°C had no change in structure and still held the crystal structure of schorl and quartz, but, the content of schorl crystal decreased. Whereas, schorl crystal completely disappeared in the sample sintered at 1050°C and two new crystal phases of hematite and spinel were formed, which resulted in disappearance of the spontaneous ‘electrostatic poles’. Hence, it was inferred that the electrostatic field of schorl crystal could enhance the MO discoloration by schorl-catalyzed Fenton-like reaction.

Review on Wood Discoloration and its Control

This paper reviews the mechanisms, types, compositions, affecting factors, prevention and remediable treatments of wood discoloration, and especially puts forward the biological control against wood stain and wood induced coloration. The authors think the followings are important: 1) Developing the low poisonous ornon-toxic, high-efficient and multi-functional anti-stain chemicalsis still an important research direction to control wood discoloration. 2) It is still very necessary to remove wood stain and restore wood original color and commercial value. 3) The biological control has little environmental pollution and its cost is low. Researches on its theories and application should be strengthened. 4) Wood color can be induced and turned to be the needed through heat treatment or ultraviolet irradiation without coloring materials, i.e. induced coloration, is agood idea to modulatewood, bamboo or rattan cane color. It is becoming a new study field.

Determination and Quantification of Susceptibility of Heritance Resistance to Root Rot of Eight Commercial Genotypes of Maize (Zea mays L.)

Maize is susceptible to a number of diseases that can infect all plant organs and serve as a constraint on cereal production. The reduction in cereal production caused by disease is estimated at an average of 9.4%. Corn root rot contributes greatly to the reduction in grain production and quality. The main objective of this work was to review the research on root rot in maize to determine the susceptibility of genotypes to root rot and to quantify the inheritance of resistance to root rot in maize. The methodology used was a complete 8 × 8 diallel design planted during the year 1999/2000. Root discoloration, plant length, root volume, effective volume and yield were the evaluated parameters. To analyze the data and determine the combinatorial abilities, genetic correlations, heritability and correlated response, diallel analysis was used. Eight parental lines;P28, I137TN, MP706, E739, MO17, B37, B73, and B14 were planted. The lines were crossed into each other, all combinations according to the complete diallel model (Model 1). The F1 was harvested after maturation. For statistical analysis, the version of the Agrobase program (2016) was used. Results show that F1 hybrids showed significant differences in root rot discoloration, plant height, root volume, effective root volume and yield. The P28 line and the B73XE739 cross had, respectively, the highest general and specific combinations. Root discoloration had the highest genetic correlation (rA = 0.47) with plant length. Broad and narrow heritability for root rot discoloration were, respectively, h2 = 0.81 and h2 = 0.51. Root rot discoloration showed the highest correlated response (CR = 0.14) on plant length.

彝药翻白草中微量元素含量的测定

[目的]测定彝药翻白草中微量元素的含量,为其开发利用提供依据。[方法]先用浓硝酸微波消解翻白草样品,然后用火焰原子吸收光谱法测定翻白草中Fe、Cu、Zn、Mn、Ca和Mg 6种元素的含量。[结果]翻白草中含有丰富的人体必需微量元素,该方法的线性关系良好(R=0.995 7～0.998 2),平均回收率在96.4%～107%(n=8),RSD在1.9%～5.5%(n=8)。[结论]该方法简单、准确,可用于彝药翻白草中多种元素的连续测定。

Fungal inoculation induces agarwood in young Aquilaria malaccensis trees in the nursery

Fungi are often used to induce agarwood inAquilariatrees. This study was conducted to evaluate the effect of several fungi on agarwood formation over time in youngAquilaria malaccensis （Lam.） trees. Typical changes in the length and light intensity of the resulting discoloration were observed after three and six month periods following inoculation. Wood samples were observed microscopically and classified into several light intensity groups. The discoloration length was meas-ured longitudinally. The duration after inoculation affected the mean of discoloration length： the 6-month old sample （1.70 cm） had a wider discoloration zone when compared to the 3-month old sample （1.17 cm）. When measuring the discoloration intensity, a positive relationship with time was perceived. Digital images, captured using a camera-equipped microscope, revealed that wood samples collected after six months appeared to be 1.8-times darker than after three months. We concluded that time, not the species of any of the tested fungi, had significant effect on discoloration length and intensity. Gas chromatography/mass spec-trometry （GCMS） analysis of the 6-month old sample yielded some important agarwood compounds such as benzylacetone, anisylacetone, guaiene and palustrol. This demonstrates that the tested fungi have the ability to induce agarwood formation in nurseryA. malaccensis trees.

Causes of color changes in wood during drying

The forest industry operates in a dynamic and global market where change and competition are the rule rather than the exception. The color of wood is one of the most attractive features for the modem wood industry. Even when wood is chosen for its structural qualities, attractive and decorative colors are usually an important factor. In many applications, particularly in furniture, decorative products, decorative veneers and flooring, accurate matching of the color of different samples is required. Wood attributes and properties are important because they have a direct bearing on market opportunities and consumer acceptance for many types of manufactured wood products. The aim of this review is to identify causes of wood discoloration and advances in drying technology to overcome this problem. Wood discoloration is a complex phenomenon, mainly affected by heat, light, physiological and biochemical reactions, as well as from attack by microorganisms.