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...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.展开更多
·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....·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.展开更多
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...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.展开更多
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 envir...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.展开更多
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 ...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.展开更多
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 Fento...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.展开更多
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 ...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.展开更多
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%. Co...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 (r<sub>A</sub> = 0.47) with plant length. Broad and narrow heritability for root rot discoloration were, respectively, h<sup>2</sup> = 0.81 and h<sub>2</sub><sub> </sub>= 0.51. Root rot discoloration showed the highest correlated response (C<sub>R</sub> = 0.14) on plant length.展开更多
Grain kernel discoloration(KD)in cereal crops leads to down-grading grain quality and substantial economic losses worldwide.Breeding KD tolerant varieties requires a clear understanding of the genetic basis underlying...Grain kernel discoloration(KD)in cereal crops leads to down-grading grain quality and substantial economic losses worldwide.Breeding KD tolerant varieties requires a clear understanding of the genetic basis underlying this trait.Here,we generated a high-density single nucleotide polymorphisms(SNPs)map for a diverse barley germplasm and collected trait data from two independent field trials for five KD related traits:grain brightness(TL),redness(Ta),yellowness(Tb),black point impact(Tbpi),and total black point in percentage(Tbpt).Although grain brightness and black point is genetically correlated,the grain brightness traits(TL,Ta,and Tb)have significantly higher heritability than that of the black point traits(Tbpt and Tbpi),suggesting black point traits may be more susceptible to environmental influence.Using genome-wide association studies(GWAS),we identified a total of 37 quantitative trait loci(QTL),including two major QTL hotspots on chromosomes 4H and 7H,respectively.The two QTL hotspots are associated with all five KD traits.Further genetic linkage and gene transcription analyses identified candidate genes for the grain KD,including several genes in the flavonoid pathway and plant peroxidase.Our study provides valuable insights into the genetic basis for the grain KD in barley and would greatly facilitate future breeding programs for improving grain KD resistance.展开更多
Millions of cataract surgeries with intraocular lens(IOL) implantation are performed worldwide. Although cataract surgery brings many benefits to the patients, the risk of various complications is still a concern. One...Millions of cataract surgeries with intraocular lens(IOL) implantation are performed worldwide. Although cataract surgery brings many benefits to the patients, the risk of various complications is still a concern. One of the infrequent adverse events but potentially affecting on patients’ visual acuity and contrast sensitivity is losing the transparency of IOL. IOL opacification may lead to IOL removal or exchange, which is unpleasant to both the patient and the surgeon. Several reports of acute IOL clouding are available in the literature describing various etiologies of this phenomenon, however, the exact mechanism remained unclear in some cases. Herein, we aimed to review the causes and outcomes of intraoperative and early postoperative IOL opacification.展开更多
The effects of Fe0 pre-corrosion by water,bicarbonate,chloride,phosphate and sulfate on the efficiency of Fe0 systems for water treatment were investigated.Batch experiments were conducted for a total duration of 72 d...The effects of Fe0 pre-corrosion by water,bicarbonate,chloride,phosphate and sulfate on the efficiency of Fe0 systems for water treatment were investigated.Batch experiments were conducted for a total duration of 72 days with MB(Methylene Blue)and MO(Methyl Orange).The efficiency of used Fe0 was assessed by characterizing the extent of MB and MO discoloration,pH variation and amount of iron released as a function of anion type.Before dye addition,used Fe0 in Fe0/sand and 100%Fe0 systems was allowed to equilibrate with H2O or the anionic solution for 0 to 44 days.Pre-corrosion has low impact on MB discoloration but has negative impact on MO discoloration.Relative to the reference system(anion free system,H2O),all the tested anions enhanced MB discoloration but decreased that of MO.HPO4 2-and HCO3-severely affects MO discoloration.The pH of the medium governs the discoloration with MB performing better at higher pH and MO doing same at lower pH.For MB,Fe0/sand system shows higher efficiency than 100%Fe0 system.But the two systems show similar efficiency for MO.Results will help in the design and functioning of Fe0 based filtration systems and other water treatment designs using Fe0.展开更多
Nitrogen deficiency induces senescence and the expression of genes encoding ammonium transporters (AMTs) in terrestrial plants where the AMT family is subdivided into AMT1 and AMT2 subfamilies. Nitrogen starvation in ...Nitrogen deficiency induces senescence and the expression of genes encoding ammonium transporters (AMTs) in terrestrial plants where the AMT family is subdivided into AMT1 and AMT2 subfamilies. Nitrogen starvation in the red seaweed Pyropia yezoensis causes senescence-like discoloration. In this study, we identified five genes in P. yezoensis encoding AMT domain-containing proteins, which were phylogenetically categorized into the AMT1 subfamily. We also found a gene encoding a Rhesus protein (Rh) that was related to, but diverged from, AMTs. Moreover, our phylogenetic analysis showed that AMT domain-containing proteins from micro- and macro-algae belonged to either the AMT1 or Rh subfamily, indicating the absence of AMT2 in algae. Gene expression analyses revealed the presence of gametophyte- and sporophyte-specific AMT1 genes that were up-regulated transiently and continually, respectively, under nitrogen-deficient conditions. In addition, up-regulated sporophyte-specific gene expression was suppressed when nitrogen was resupplied. Accordingly, an expansion of the ancient AMT gene has produced AMT1 functional variants differing in temporal and nitrogen starvation-inducible expression patterns during the life cycle of P. yezoensis. These findings help elucidate the unique nutrition starvation responses involving functionally diverse AMT1 and Rh subfamilies in red seaweed.展开更多
Aim: The aim of this study was to evaluate in vitro the tooth color alterations associated with two intracanal medicaments, calcium hydroxide and calcium hydroxide combined with aquatic solution of chlorexidine, for u...Aim: The aim of this study was to evaluate in vitro the tooth color alterations associated with two intracanal medicaments, calcium hydroxide and calcium hydroxide combined with aquatic solution of chlorexidine, for up to three months post-treatment. Materials & Methods: Thirty-one intact human anterior mature teeth were used. Black adhesive tape with a 4-mm diameter window was used to standardize the enamel surface intended for color analysis. After access cavity preparation, cleaning and shaping were completed with rotary nickel-titanium files. The teeth were randomly divided into two groups (n = 15), each according to the intracanal medicament used: (A) calcium hydroxide paste (UltraCalTM XSTM Ultradent Products, Inc., USA);(B) 2% chlorhexidine aquatic solution combined with pure calcium hydroxide powder. In one tooth, no medicament was placed (pilot). The enamel surfaces were colormetrically evaluated at the following time intervals: before placing the medicaments, immediately after placement, after 1 week as well as after 1, 2 and 3 months post-treatment. The CIE color parameters (L*, a*, b*) were recorded for each material and the corresponding color differences (ΔΕ) were calculated and statistically analyzed. Results: The most significant factor in tooth discoloration was the time intervals. The most important changes of the ΔΕ values were recorded after the 1st week and after the 3rd month. L* presented an overall increase in both groups, resulting in a higher lightness of the crown color. Only L* did show significant alterations during specific time intervals. Conclusions: There is no statistically significant relationship between the type of intracanal medicament and tooth color alteration. Time is statistically the most important factor affecting the discoloration ability of Ca(OH)2, either combined with chlorexidine or not. Consequently, the clinician should always take this into account before using such medicaments for a long-term treatment.展开更多
Amelogenesis imperfecta is an unusual hereditory disorder affecting both primary and permanent dentition. We present a rare case of hypocalcified auto-somal recessive amelogenesis imperfecta occuring in primary dentit...Amelogenesis imperfecta is an unusual hereditory disorder affecting both primary and permanent dentition. We present a rare case of hypocalcified auto-somal recessive amelogenesis imperfecta occuring in primary dentition in a 7-year-old girl with a family history of consanguineous marriage. Clinical and radiological examination revealed discoloration and hypoplasia of enamel with easy chipping affecting both maxillary and mandibular dentition.展开更多
Sports and energy drinks are consumed by more peoplethan ever. Sports and energy drinks may enhance physical resistance, stimulate metabolism, prevent rehydration and replace electrolytes during high activity efforts....Sports and energy drinks are consumed by more peoplethan ever. Sports and energy drinks may enhance physical resistance, stimulate metabolism, prevent rehydration and replace electrolytes during high activity efforts. However, these drinks often have a low pH and are acidic, which can erode enamel and dentin, and increase dentine hypersensitivity. In addition to the adverse effects of sports and energy drinks on tooth structures, they often have the potential to damage restorative materials. These drinks often contain artificial colors which have potential to discolor resin composite materials and glass ionomers. The acidic nature of these drinks could also lead to a degradation, increase in wear, and roughening of the surface of the restorative materials. Many of the negative consequences of sport and energy drinks can be related to their overconsumption among children and teenagers. Patients should be advised to have a healthy diet, and consume soft and energy drinks in moderation, to avoid any negative dental or health consequences. The overconsumption of sports and energy drinks which are high in sugar and have the lowest pH are most likely to cause avoidable dental problems.展开更多
Treatment of yellow dye 23 by heterogeneous Fenton-like process was studied using iron rich soil as an iron source. The iron rich soil sample was characterized by XRD, SEM and BET analysis. XRD pattern indicates that ...Treatment of yellow dye 23 by heterogeneous Fenton-like process was studied using iron rich soil as an iron source. The iron rich soil sample was characterized by XRD, SEM and BET analysis. XRD pattern indicates that the iron rich soil is made of goethite and hematite. The reaction was systematically investigated under various experimental conditions such as pH, iron rich soil dosage, oxidant and dye concentrations. The result revealed that using iron rich soil as catalyst led to high discoloration efficiency (97.71% for 140 min of treatment) at pH = 2.5, 2 g/L iron rich soil and 16 m·mol/L H<sub>2</sub>O<sub>2</sub>. The degradation kinetics of acid yellow 23 can be described by a pseudo-first-order reaction following the Langmuir-Hinshelwood mechanism. The main roles of hydroxyl radicals in degradation process were investigated by adding of various radical scavengers.展开更多
Green,energy conservation and environmental protection have increasingly become the theme of the sustained and healthy development of cities against the background of new urbanization,which indicates that the problem ...Green,energy conservation and environmental protection have increasingly become the theme of the sustained and healthy development of cities against the background of new urbanization,which indicates that the problem of building energy consumption has received growing attention.This paper explores the impact of energy-saving decorations in flexible interior space on energy-saving effect of buildings so as to broaden the horizon of energy conservation in building,thereby alleviating the problem of energy shortage in China.展开更多
文摘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.
基金Supported by Science and Technology Projects of Guangdong Province,China(No.2007B031002001,No.2008B030301086)
文摘·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.
文摘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.
文摘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.
基金the National Natural Science Foundation of China(Grant Nos.51372200 and 51772243)the Foundation of the State Key Laboratory of Solidification Processing in NWPU(Grant No.SKLSP201753)+2 种基金Scientific Research Plan Projects of Shaanxi Education Department(Grant No.16JK1551)Technology Innovation Programme of Xi’an University of Technology(Grant No.2016CX030)China Postdoctoral Science Foundation(Grant No.2016M592824)
文摘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.
基金Supported by Heilongjiang Science Fundation for Young Scholars (Grant No. QC07C02)Scientific Foundation of Heilongjiang Education Department, China (Grant No. 11531035)
文摘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.
基金supported by the Natural Science Foundation of Heilongjiang Province, China (Grant No E200906)Scientific Foundation of Heilongjiang Office of Education (Grant No 11531035)the Young Founds of the National Natural Science Foundation of China (Grant No 51002040)
文摘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.
文摘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 (r<sub>A</sub> = 0.47) with plant length. Broad and narrow heritability for root rot discoloration were, respectively, h<sup>2</sup> = 0.81 and h<sub>2</sub><sub> </sub>= 0.51. Root rot discoloration showed the highest correlated response (C<sub>R</sub> = 0.14) on plant length.
基金supported by the Australian Grain Research and Development Corporation(UMU00047)。
文摘Grain kernel discoloration(KD)in cereal crops leads to down-grading grain quality and substantial economic losses worldwide.Breeding KD tolerant varieties requires a clear understanding of the genetic basis underlying this trait.Here,we generated a high-density single nucleotide polymorphisms(SNPs)map for a diverse barley germplasm and collected trait data from two independent field trials for five KD related traits:grain brightness(TL),redness(Ta),yellowness(Tb),black point impact(Tbpi),and total black point in percentage(Tbpt).Although grain brightness and black point is genetically correlated,the grain brightness traits(TL,Ta,and Tb)have significantly higher heritability than that of the black point traits(Tbpt and Tbpi),suggesting black point traits may be more susceptible to environmental influence.Using genome-wide association studies(GWAS),we identified a total of 37 quantitative trait loci(QTL),including two major QTL hotspots on chromosomes 4H and 7H,respectively.The two QTL hotspots are associated with all five KD traits.Further genetic linkage and gene transcription analyses identified candidate genes for the grain KD,including several genes in the flavonoid pathway and plant peroxidase.Our study provides valuable insights into the genetic basis for the grain KD in barley and would greatly facilitate future breeding programs for improving grain KD resistance.
文摘Millions of cataract surgeries with intraocular lens(IOL) implantation are performed worldwide. Although cataract surgery brings many benefits to the patients, the risk of various complications is still a concern. One of the infrequent adverse events but potentially affecting on patients’ visual acuity and contrast sensitivity is losing the transparency of IOL. IOL opacification may lead to IOL removal or exchange, which is unpleasant to both the patient and the surgeon. Several reports of acute IOL clouding are available in the literature describing various etiologies of this phenomenon, however, the exact mechanism remained unclear in some cases. Herein, we aimed to review the causes and outcomes of intraoperative and early postoperative IOL opacification.
文摘The effects of Fe0 pre-corrosion by water,bicarbonate,chloride,phosphate and sulfate on the efficiency of Fe0 systems for water treatment were investigated.Batch experiments were conducted for a total duration of 72 days with MB(Methylene Blue)and MO(Methyl Orange).The efficiency of used Fe0 was assessed by characterizing the extent of MB and MO discoloration,pH variation and amount of iron released as a function of anion type.Before dye addition,used Fe0 in Fe0/sand and 100%Fe0 systems was allowed to equilibrate with H2O or the anionic solution for 0 to 44 days.Pre-corrosion has low impact on MB discoloration but has negative impact on MO discoloration.Relative to the reference system(anion free system,H2O),all the tested anions enhanced MB discoloration but decreased that of MO.HPO4 2-and HCO3-severely affects MO discoloration.The pH of the medium governs the discoloration with MB performing better at higher pH and MO doing same at lower pH.For MB,Fe0/sand system shows higher efficiency than 100%Fe0 system.But the two systems show similar efficiency for MO.Results will help in the design and functioning of Fe0 based filtration systems and other water treatment designs using Fe0.
文摘Nitrogen deficiency induces senescence and the expression of genes encoding ammonium transporters (AMTs) in terrestrial plants where the AMT family is subdivided into AMT1 and AMT2 subfamilies. Nitrogen starvation in the red seaweed Pyropia yezoensis causes senescence-like discoloration. In this study, we identified five genes in P. yezoensis encoding AMT domain-containing proteins, which were phylogenetically categorized into the AMT1 subfamily. We also found a gene encoding a Rhesus protein (Rh) that was related to, but diverged from, AMTs. Moreover, our phylogenetic analysis showed that AMT domain-containing proteins from micro- and macro-algae belonged to either the AMT1 or Rh subfamily, indicating the absence of AMT2 in algae. Gene expression analyses revealed the presence of gametophyte- and sporophyte-specific AMT1 genes that were up-regulated transiently and continually, respectively, under nitrogen-deficient conditions. In addition, up-regulated sporophyte-specific gene expression was suppressed when nitrogen was resupplied. Accordingly, an expansion of the ancient AMT gene has produced AMT1 functional variants differing in temporal and nitrogen starvation-inducible expression patterns during the life cycle of P. yezoensis. These findings help elucidate the unique nutrition starvation responses involving functionally diverse AMT1 and Rh subfamilies in red seaweed.
文摘Aim: The aim of this study was to evaluate in vitro the tooth color alterations associated with two intracanal medicaments, calcium hydroxide and calcium hydroxide combined with aquatic solution of chlorexidine, for up to three months post-treatment. Materials & Methods: Thirty-one intact human anterior mature teeth were used. Black adhesive tape with a 4-mm diameter window was used to standardize the enamel surface intended for color analysis. After access cavity preparation, cleaning and shaping were completed with rotary nickel-titanium files. The teeth were randomly divided into two groups (n = 15), each according to the intracanal medicament used: (A) calcium hydroxide paste (UltraCalTM XSTM Ultradent Products, Inc., USA);(B) 2% chlorhexidine aquatic solution combined with pure calcium hydroxide powder. In one tooth, no medicament was placed (pilot). The enamel surfaces were colormetrically evaluated at the following time intervals: before placing the medicaments, immediately after placement, after 1 week as well as after 1, 2 and 3 months post-treatment. The CIE color parameters (L*, a*, b*) were recorded for each material and the corresponding color differences (ΔΕ) were calculated and statistically analyzed. Results: The most significant factor in tooth discoloration was the time intervals. The most important changes of the ΔΕ values were recorded after the 1st week and after the 3rd month. L* presented an overall increase in both groups, resulting in a higher lightness of the crown color. Only L* did show significant alterations during specific time intervals. Conclusions: There is no statistically significant relationship between the type of intracanal medicament and tooth color alteration. Time is statistically the most important factor affecting the discoloration ability of Ca(OH)2, either combined with chlorexidine or not. Consequently, the clinician should always take this into account before using such medicaments for a long-term treatment.
文摘Amelogenesis imperfecta is an unusual hereditory disorder affecting both primary and permanent dentition. We present a rare case of hypocalcified auto-somal recessive amelogenesis imperfecta occuring in primary dentition in a 7-year-old girl with a family history of consanguineous marriage. Clinical and radiological examination revealed discoloration and hypoplasia of enamel with easy chipping affecting both maxillary and mandibular dentition.
文摘Sports and energy drinks are consumed by more peoplethan ever. Sports and energy drinks may enhance physical resistance, stimulate metabolism, prevent rehydration and replace electrolytes during high activity efforts. However, these drinks often have a low pH and are acidic, which can erode enamel and dentin, and increase dentine hypersensitivity. In addition to the adverse effects of sports and energy drinks on tooth structures, they often have the potential to damage restorative materials. These drinks often contain artificial colors which have potential to discolor resin composite materials and glass ionomers. The acidic nature of these drinks could also lead to a degradation, increase in wear, and roughening of the surface of the restorative materials. Many of the negative consequences of sport and energy drinks can be related to their overconsumption among children and teenagers. Patients should be advised to have a healthy diet, and consume soft and energy drinks in moderation, to avoid any negative dental or health consequences. The overconsumption of sports and energy drinks which are high in sugar and have the lowest pH are most likely to cause avoidable dental problems.
文摘Treatment of yellow dye 23 by heterogeneous Fenton-like process was studied using iron rich soil as an iron source. The iron rich soil sample was characterized by XRD, SEM and BET analysis. XRD pattern indicates that the iron rich soil is made of goethite and hematite. The reaction was systematically investigated under various experimental conditions such as pH, iron rich soil dosage, oxidant and dye concentrations. The result revealed that using iron rich soil as catalyst led to high discoloration efficiency (97.71% for 140 min of treatment) at pH = 2.5, 2 g/L iron rich soil and 16 m·mol/L H<sub>2</sub>O<sub>2</sub>. The degradation kinetics of acid yellow 23 can be described by a pseudo-first-order reaction following the Langmuir-Hinshelwood mechanism. The main roles of hydroxyl radicals in degradation process were investigated by adding of various radical scavengers.
基金Sponsored by Education Science Project of the 13th Five-Year Plan of Jiangxi Province(16YB041)
文摘Green,energy conservation and environmental protection have increasingly become the theme of the sustained and healthy development of cities against the background of new urbanization,which indicates that the problem of building energy consumption has received growing attention.This paper explores the impact of energy-saving decorations in flexible interior space on energy-saving effect of buildings so as to broaden the horizon of energy conservation in building,thereby alleviating the problem of energy shortage in China.
