MAY 2021最新文献

{"title":"Peracetate/singlet oxygen chemistry used in post-bleaching of kraft pulp as a practical oxidant for paper machines","authors":"W. Buschmann, H. Kaplan","doi":"10.32964/tj20.5.297","DOIUrl":"https://doi.org/10.32964/tj20.5.297","url":null,"abstract":"The use of a novel sodium peracetate/singlet oxygen chemistry for brightening bleached kraft pulp shows exciting potential for technical performance, supply logistics, safety, and cost reduction. Potential chemical carryover to the paper machine raises questions about whether peracetate will impact paper machine performance, such as metal corrosion, useful press felt life, and interference with existing biocide programs or paper machine chemistry. \u0000Sodium peracetate/singlet oxygen chemistry can be used in high-density storage chests for brightening/whitening and to increase color stability. Any oxidant used directly before the paper machine has the possibility of impacting paper machine operations. Traditional oxidants used in bleaching, such as chlorine dioxide and hydrogen peroxide, are known to cause corrosion on machinery metals and press felts. Hydrogen peroxide residuals can interfere with common biocide programs. Traditional oxidants used in biocide treatments themselves significantly degrade press felt life when the rule-of-thumb concentration thresholds are exceeded. Sodium peracetate is evaluated in this paper for its impact on nylon press felt fiber degradation, metal corrosion, and interference with typical biocide programs.\u0000Laboratory results indicate that sodium peracetate/singlet oxygen chemistry is less corrosive than chlorine, bro-mine, and hydrogen peroxide on press felt nylon fiber and can therefore be used at higher levels than those chemistries to increase brightness without increasing negative downstream impact. Sodium peracetate can also be used with current biocide programs without negative impacts such as consumptive degradation. Higher residuals of per-acetate going to the paper machine may be useful as a biocide itself and can complement existing programs, allowing those programs to stay within their safe operating levels and thereby extend press felt useful life.","PeriodicalId":371150,"journal":{"name":"MAY 2021","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126872347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact and feasibility of a membrane pre-concentration step in kraft recovery","authors":"Max KLEIMAN-LYNCH, Diego F. Rivera, Stephen H Frayne, Brent D. Keller","doi":"10.32964/tj20.5.331","DOIUrl":"https://doi.org/10.32964/tj20.5.331","url":null,"abstract":"Emerging robust membrane systems can perform the first section of black liquor (BL) concentration by separating clean water from the black liquor stream using only mechanical pressure. By doing so, they can reduce the steam and energy required for BL concentration. Because of the high osmotic pressure of strong BL, a membrane system would not replace evaporators but would operate in series, performing the first section of BL concentration. \u0000In this work, we use a multi-effect evaporator (MEE) model to quantify the steam and energy savings associated with installing membrane systems of different sizes. When maintaining a constant BL solids throughput, we find that a pulp mill could reduce steam usage in its evaporators by up to 65%. Alternatively, a membrane system could also serve to increase BL throughput of the recovery train. We find that a membrane system capable of concentrating BL to 25% could double the BL solids throughput of a mill’s evaporators at the same steam usage. We also demonstrate that installing a membrane system before an MEE would minimally affect key operating parameters such as steam pressures and BL solids concentrations in each effect. This indicates that installing a membrane pre-concentration system would be nonintrusive to a mill’s operations.","PeriodicalId":371150,"journal":{"name":"MAY 2021","volume":"181 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124541691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gas dispersion in the oxygen delignification process","authors":"Jari Käyhkö, Heikki Mutikainen, K. Peltonen, Riku Kopra, M. Honkanen","doi":"10.32964/tj20.5.311","DOIUrl":"https://doi.org/10.32964/tj20.5.311","url":null,"abstract":"There has been very little knowledge about the state of gas dispersion in the oxygen delignification process, even though this has a major impact on the performance of the reactor. This paper presents a new continu-ous inline method for measuring oxygen bubble size distribution in the reactor, as well as results from studies con-ducted in softwood and hardwood lines. This new measurement worked well, and new information about oxygen bubble size, as well as how different reactor conditions affected the distribution, was obtained. For example:\u0000• In the softwood line, the mean volume-weighted bubble size was about 0.1 mm, whereas in the hardwood line, this size was almost 10 times higher. For both lines, there was considerable variation in the measured bubble size over the long term.\u0000• For both lines, an increase in mixer rotation speed caused a discernible decrease in the bubble size, and an increase in oxygen charge caused a discernible increase in the bubble size.\u0000• In the softwood line, no coalescence of the bubbles in the reactor was observed, but in the hardwood line, some coalescence of the larger bubbles occurred.\u0000• In the test conducted in the hardwood line, the use of brownstock washer defoamer caused a discernible increase in oxygen bubble size.\u0000• In the hardwood line, reactor pressure had a noticeable effect on the amount of delignification, which indicated that improving mass transfer of oxygen (e.g., by decreasing the oxygen bubble size, in this case) should also have an increasing effect on the delignification.","PeriodicalId":371150,"journal":{"name":"MAY 2021","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122248798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hop (Humulus lupulus L.) phenology, growth, and yield under subtropical climatic conditions: Effects of cultivars and crop management","authors":"Aleyda Maritza Acosta Rangel, J. Rechcigl, S. Bollin, Z. Deng, S. Agehara","doi":"10.21475/ajcs.21.15.05.p3192","DOIUrl":"https://doi.org/10.21475/ajcs.21.15.05.p3192","url":null,"abstract":"Commercial hop (Humulus lupulus L.) production occurs predominantly in temperate climates. The objectives of this study were to characterize the phenology of hops under subtropical climatic conditions and to determine the growth and yield potential. Two field experiments were conducted in Florida, southeastern United States. Rhizomes were planted in April. Data were collected during the establishment year. In the first experiment, we evaluated 7 American, 5 European, and 1 Japanese cultivars in a randomized complete block design. Bine height, main bine number, lateral shoot number, and dry cone yield (10% moisture) were recorded. Yield varied considerably, ranging from 0 to 197 kg ha–1. The top three yielding cultivars were ‘Cascade’, ‘CTZ’, and ‘Nugget’, all of which were American cultivars. Yield had positive correlations with main bine number and lateral shoot number, but it had no significant correlation with bine height. In the second experiment, we determined the duration of each phenological stage in ‘Cascade’. Reproductive phenology was characterized by premature and nonsynchronous flowering. Prolonged flowering resulted in multiple harvests over 61 days, starting in mid-June. We also evaluated crop management treatments, which consisted of three levels of hill spacing (76, 91, and 107 cm) and two nitrogen (N) rates (109 and 130 kg ha–1) in a factorial combination. Treatments were arranged in a split-plot design with hill spacing as the main-plot factor. Yield on a per-area basis increased with reducing hill spacing and increasing N rate by 41% and 38%, respectively. Our results demonstrate unique reproductive phenology of hops under subtropical climatic conditions, which prevents once-overharvest but enables the off-season supply of fresh hops over an extended period. This study provides a benchmark to develop production strategies for hops suitable to subtropical climates.","PeriodicalId":371150,"journal":{"name":"MAY 2021","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134532293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fermentation profile and nutritive value of maize silage with Brachiaria species","authors":"D. A. A. Teixeira, K. Costa, W. F. Souza, E. Severiano, K. C. Guimarães, Jessika Torres da Silva, S. S. Oliveira, Mariana Borges de Castro Dias","doi":"10.21475/ajcs.21.15.05.p3004","DOIUrl":"https://doi.org/10.21475/ajcs.21.15.05.p3004","url":null,"abstract":"The production of mixed silages is a technique that has emerged as a viable alternative for supplying nutrients during food-shortage periods in the dry season, in addition to guaranteeing the highest ensiled mass production. The aim of this study was to evaluate the fermentation profile and nutritional value of maize silage with Brachiaria species. The experiment was carried out under a completely randomized experimental design with four replications. The treatments comprised the following types of silage: maize; Congo grass; Xaraes palisadegrass; Paiaguas palisadegrass; maize + 30% Congo grass; maize + 30% Xaraes palisadegrass; and maize + 30% Paiaguas palisadegrass. For ensilage, maize and grasses were harvested in a 105-day cycle at a depth of 20 cm from the soil surface. According to the results, the maize silage and mixed silages presented an adequate fermentation profile and improved nutritional value. Among the investigated Brachiaria species, Paiaguas palisadegrass emerged because of its protein increase and low ADF content; therefore, this species is recommended for use in mixed silage production. Thus, mixed silage can be used as an alternative for animal feed supplementation","PeriodicalId":371150,"journal":{"name":"MAY 2021","volume":"54 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123179766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Alteration of dry matter accumulation under soil moisture fluctuation stress in rice (Oryza sativa L.)","authors":"C. N. Ichsan, B. Basyah, Sabaruddin Zakaria, Efendi Efendi","doi":"10.21475/ajcs.21.15.05.p3142","DOIUrl":"https://doi.org/10.21475/ajcs.21.15.05.p3142","url":null,"abstract":"Drought-flood abrupt alterations (DFAA) is a condition in drought season when sudden rain inundate rice plants. These events are due to the high frequency of extreme climate events that might pose a threat to rice productivity. DFAA causes cumulative stress on rice which affects crop growth and alters dry matter accumulation. This study aims to understand the effect of DFAA to dry matter accumulation by assessing six rice varieties under DFAA. Three treatments were provided such as continuously irrigated as non-water stress (NS) as a control; drought to water stress -35 kPa (DFAA1) followed by sudden flood; drought to severe water stress -70 kPa (DFAA2) followed by abrupt floods; repeated until harvest. The study found that the alteration of dry matter accumulation was determined by root length, root weight, shoot length and shoot weight. Only varieties that are able to increase root depth under water stress fluctuation will be able to maintain the yield. The results of study showed that root depth was positively correlated with shoot length (r = 0.68), shoot weight (r = 0.62), root weight (r = 0.57), percentage of filled grain (r = 0.55) and number of filled grain per hill (r = 0.49). Shoot length was positively correlated with shoot weight (r = 0.83), root weight (r = 0.75) and the number of filled grain (r = 0.62), while shoot weight was only positively correlated with root weight (r = 0.88). This means that only root depth and shoot length can increase the seed setting rate and the number of filled grains per hill. Furthermore, at DFAA2, the percentage of filled grain was highest in Sipulo followed by Bo Santeut, Sanbei, Towuti and Situ Patenggang, which mean that varieties with deeper and heavier root dry weight can maintain higher yields than shallow and low root dry weight. The result of the study may allow to select rice varieties that are resistant to multilevel water-stress and able to maintain the potential yield, by looking at root depth, root dry weight, and through their grain yield in general. These traits could become key indicators for resistance to DFAA stress in rice. It is also necessary to pay attention to the fluctuation of soil water content in critical phases, especially in the reproductive phase and grain filling","PeriodicalId":371150,"journal":{"name":"MAY 2021","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128431063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multidimensional scaling for divergence analysis in pepper","authors":"J. D. Mesquita, E. R. Rêgo, A. S. Pessoa, Anderson Rodrigo da Silva, J. J. S. Neto, M. M. Rêgo","doi":"10.21475/ajcs.21.15.05.p2693","DOIUrl":"https://doi.org/10.21475/ajcs.21.15.05.p2693","url":null,"abstract":"Pepper plants of the genus Capsicum present wide genetic variability for phenotypical characters. The joint analysis of quantitative and qualitative characters is a more complete indicator to identify the existing variability in populations of plants. This work aimed to evaluate the genetic divergence within F3 populations of Capsicum annuum L. through the multidimensional scaling based on the joint analysis of quantitative and qualitative data. The work was developed in at the Center of Agrarian Sciences of the Federal University of Paraíba, state of Paraíba, Brazil. Eight populations of an F3 generation were employed, performing the characterization of 36 qualitative and quantitative characteristics. The experimental design was in randomized blocks, with eight treatments and 50 replications. The non-metric multidimensional scaling (nMDS) was performed based on Gower’s dissimilarity matrixes. Dispersion diagrams were built to present the nMDS solutions in the bidimensional space. The nMDS mapping was efficient on estimating divergence within populations with Kruskal’s Stress below 20%. The internal uniformity presented by populations P-4, P-5, P-6, P-7, and P-8 is an indicator that the genotypes of these populations are suitable to be used in future genetic breeding programs of ornamental peppers. Conversely, populations P-1, P-2, and P-3 presented the greatest dispersion, characterizing phenotypical variability. The multidimensional scaling was efficient to estimate the genetic divergence among and within F3 populations of ornamental pepper","PeriodicalId":371150,"journal":{"name":"MAY 2021","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114661942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soil CO2 emission in ‘Tifton 85’ bermudagrass pasture fertilized with liquid pig slurry","authors":"Adilson Amorim Brandão, E. Couto, R. Rodrigues, O. L. S. Weber, O. B. P. Júnior","doi":"10.21475/ajcs.21.15.05.p2959","DOIUrl":"https://doi.org/10.21475/ajcs.21.15.05.p2959","url":null,"abstract":"The application of liquid pig slurry (LPS) to pastures offers potential as a fertilizer but could have a direct influence on soil CO2 emissions. This study evaluated soil carbon dioxide emissions after successive LPS applications to soils under pasture cultivation. The experiment was carried out on ‘Tifton-85’ bermudagrass pasture cultivated in a red-yellow oxisol soil in the municipality of Lucas do Rio Verde-MT, Brazil. Two treatments were evaluated: the control and an application of 20 m3 ha-1 of LPS after each cut of the pasture. The CO2 emissions from the soil were determined using a high-precision infrared gas analyzer. Soil temperature and soil moisture were determined as were micrometeorological variables. The application of LPS had a significant effect on soil C-CO2 flow. The average flow of C-CO2 from the soil for the control treatment and with the application of LPS was 0.236 g C-CO2 m-2 h-1 and 0.291 g C-CO2 m-2 h-1, respectively. The application of LPS increased the accumulated CO2 emissions from the soil by 23.2%. Soil temperature and moisture are the main factors regulating the process of soil CO2 emission. These factors therefore need to be considered when evaluating the impact of LPS application on greenhouse gas emissions","PeriodicalId":371150,"journal":{"name":"MAY 2021","volume":"536 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133599183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of glyphosate and glufosinate on nutritional content and agronomic performance of maize possessing cp4epsps and pat transgenes","authors":"G. V. Araújo, A. Albrecht, L. Albrecht, H. W. Carvalho, R. A. Migliavacca, A. F. M. Silva","doi":"10.21475/ajcs.21.15.05.p3193","DOIUrl":"https://doi.org/10.21475/ajcs.21.15.05.p3193","url":null,"abstract":"The aim of this study was to check the tolerance level of maize possessing the transgenes cp4epsps and pat, exposed to high rates of glyphosate or glufosinate. Field experiments were carried out in 2016/17 at the first growing season; and the other in the second growing season, in Palotina, state of Paraná (PR), Brazil. The design was completely randomized block with 4 replications, which were set up with variations of rates of herbicides: glyphosate (0; 2,160; 4,320; 6,480 and 8,640 g ae ha-1) (experiment 1) and glufosinate (0; 1,500; 3,000; 4,500 and 6,000 g ai ha-1) (experiment 2). The application was performed at the V4 stage. Plants were evaluated for injuries, final plant height, stem diameter, 100-grain mass, yield and content of P, K, S, Fe, Cu and Zn. The results show that there was no reduction in yield and 100-grain mass, as well as changes in nutrient contents, even with the use of high rates of glyphosate and glufosinate. This is explained by the rapid recovery of maize hybrids under favorable developmental conditions. Despite causing injuries and decreased height, application of glyphosate (up to 8,640 g ae ha-1) or glufosinate (up to 6,000 ai ha-1) did neither reduce yield and 100-grain mass nor the nutrient contents of grains. This shows the high selectivity of these herbicides. Nonetheless, crop injury and reduction in height were observed in maize plants for herbicide application. This indicates the risks of using herbicides above the rates recommended in the package insert, despite the absence of deleterious effects on yield","PeriodicalId":371150,"journal":{"name":"MAY 2021","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116011083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of Trichoderma harzianum on the physiological quality of cowpea seeds","authors":"M. L. Pimentel, H. V. Castro, Mike Kirixi Munduruku, Larissa Conceição Cunha Ponte, D. N. M. Alves, R. B. Pinto, Juan Daniel Villacis Fajardo, Nancy Andrea Villacis Fajardo, Deyviane Ramos Alves, Laércio S. Silva","doi":"10.21475/ajcs.21.15.05.p2865","DOIUrl":"https://doi.org/10.21475/ajcs.21.15.05.p2865","url":null,"abstract":"The use of fungi in seed treatment can improve the plant's physiological characteristics. The aim of this study was to evaluate the influence of the use of Trichoderma harzianum on the physiological quality of bean seeds. The experiment was set up and conducted in the forest seed laboratory of the Federal University of Western Para, in a randomized design, using 4 procedures on the basis of a colony forming unit (CFU): T1 (0 CFU), T2 (4 x 109 CFU), T3 (8 x 109 CFU) and T4 (12 x 109 CFU), with 5 repetitions. Germination percentage (G%), germination speed index (GSI), hypocotyl length (HL) and radicle length (RL) were evaluated as variables. The data were analyzed by variance analysis and the averages were compared using the Tukey test (p≤0.05), in addition to the regression analysis, using the Minitab© version 18 statistical software. There were differences between the germination percentage tests, in which T2 obtained 100% of germinated seeds, for GSI it was observed that T2 and T3 were equal and superior to the other treatments, while for RL T1 and T2 obtained the best results, however, for HL there were no statistical differences between treatments. T2 was more efficient in the physiological quality of seeds to germination percentage and germination speed index","PeriodicalId":371150,"journal":{"name":"MAY 2021","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128495286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}