January 2021最新文献

{"title":"Co-ground mineral/microfibrillated cellulose composite materials: Recycled fibers, engineered minerals, and new product forms","authors":"D. Skuse, J. Phipps, T. Larson","doi":"10.32964/tj20.1.49","DOIUrl":"https://doi.org/10.32964/tj20.1.49","url":null,"abstract":"When pulp and minerals are co-processed in suspension, the mineral acts as a grinding aid, allowing cost-effective production of mineral/microfibrillated cellulose (MFC) composite materials. This processing uses robust milling equipment and is practiced at industrial scale. The resulting products can be used in many applications, including as wet- and dry-strength aids in paper and board production.\u0000Previously, we have reported that use of these MFC composite materials in fiber-based applications allow generally improved wet and dry mechanical properties with concomitant opportunities for cost savings, property improvements, or grade developments.\u0000Mineral/MFC composites made with recycled pulp feedstocks were shown to offer at least equivalent strength aid performance to composites made using virgin fibers.\u0000Selection of mineral and fiber allows preparation of mineral/MFC composites with a range of properties. For example, the viscosity of such formulations was shown to be controlled by the shape factor of the mineral chosen, effective barrier formulations were prepared, and mineral/MFC composites with graphite as the mineral were prepared.\u0000High-solids mineral/MFC composites were prepared at 75% total solids (37% fibril solids). When resuspended and used for papermaking, these high-solids products gave equivalent performance to never-dried controls.","PeriodicalId":436878,"journal":{"name":"January 2021","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123001461","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 foamed additives to the surface of wet handsheets","authors":"Bliss Terry, Luo Mingxiang, M. Nicholas","doi":"10.32964/tj20.1.9","DOIUrl":"https://doi.org/10.32964/tj20.1.9","url":null,"abstract":"We explored the application of foamed wet-end additives onto wet handsheets to qualify our method of application and to demonstrate the method’s usefulness for prescreening additives and foaming agents for packaging applications.\u0000We modified a laboratory drawdown coating machine to allow coating of wet handsheets with foamed additives. Initial sheet solids were adjusted to a target of 8%–25% by vacuum. Foam layer thickness was set mechanically. After application, the foamed additives were drawn into the sheet with vacuum. The additive dosage was adjusted by altering its concentration within the foaming formulation. We evaluated more than 100 foaming agents and 10 strength additives, comparing wet-end and foam-assisted addition with no addition on recycled linerboard and virgin linerboard furnish. Foam-assisted addition typically displayed a much steeper dose-response curve and much higher maximum strength levels than wet-end addition. \u0000Our results suggest potential target applications for this technology, such as lightweighting, and improved strength performance in mills with relatively closed water systems, where strength aids added into the wet end are adversely influenced by accumulation of inorganic ions and organic species.","PeriodicalId":436878,"journal":{"name":"January 2021","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129091919","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":"The effect of microfibrillated cellulose on the wet-web strength of paper","authors":"J. Phipps, T. Larson, Mark Paradis, D. Tănase","doi":"10.32964/tj20.1.61","DOIUrl":"https://doi.org/10.32964/tj20.1.61","url":null,"abstract":"The wet-web strength of paper immediately after the press section of a paper machine is a critical factor in determining machine runnability. However, it is difficult to determine at commercial scale, because the web has to be broken and production interrupted in order to obtain a sample for measurement. The use of microfibrillated cellulose (MFC) is believed to increase wet-web strength, as it has allowed filler level increases of 10% or more on many commercial paper machines.\u0000In this paper, we describe a laboratory method for estimating the effect of MFC on wet sheet strength after pressing, as well as actual measurements of wet-web strength from a pilot paper machine trial. These experiments have demonstrated the positive effect of MFC. At solids contents in the range typically observed after pressing, sheets with MFC at fixed filler content are significantly stronger, but also wetter, than those without it. When the use of MFC is combined with a typical increase in filler content, the wet web remains slightly stronger, but also becomes drier than the reference condition. These results are compatible with the theory put forward by van de Ven that wet-web strength is mainly a result of friction between entangled fibers, and they also suggest that the presence of MFC increases this friction.","PeriodicalId":436878,"journal":{"name":"January 2021","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126502240","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":"The effect of contact time between CPAM and colloidal silica on the flocculation behavior in the approach flow","authors":"P. Krochak, K. Johansson, I. S. Pio","doi":"10.32964/tj20.1.39","DOIUrl":"https://doi.org/10.32964/tj20.1.39","url":null,"abstract":"Multicomponent wet-end systems have become increasingly common in papermaking, with the objective of improving the retention-formation-dewatering relationship. It is quite common to use at least a cationic polymer, often in combination with an anionic microparticle. In some cases, a fixative is also used. However, there is still debate on the optimal implementation of these systems. In particular, optimizing the contact time of the cationic polymer prior to addition of the anionic microparticle is still poorly understood. \u0000In this work, we investigate the effect of the contact time of a cationic polyacrylamide (CPAM) prior to addition of colloidal silica on the flocculation response in a flowing fiber suspension. The effect of using a fixative is also investigated. Focused beam reflectance measurements (FBRM) are combined with zeta-potential measurements for optimizing the addition levels of a two- and three-component system, as well as for elucidating the effect of contact time on CPAM performance. Trials are then performed on a pilot scale flow loop, where the time between addition of these two components is varied and the resulting flocculation response is characterized using high-speed filming and image analysis techniques. It is shown that the efficacy of CPAM can be improved through use of a fixative and that a longer CPAM contact time may be beneficial in terms of immediate flocculation; however, hydrodynamic shear tends to dominate the flocculation response regardless of contact time due to floc rupture.","PeriodicalId":436878,"journal":{"name":"January 2021","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132851473","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":"Understanding wet tear strength at varying moisture content in handsheets","authors":"Adele Panek, J. Panek, James Faught, P. Hart","doi":"10.32964/tj20.1.29","DOIUrl":"https://doi.org/10.32964/tj20.1.29","url":null,"abstract":"A laboratory study was conducted looking at the effects of moisture content on wet tear strength in handsheets. Three different wetting techniques were used to generate the wet tear (Elmendorf-type) data at varying moisture levels, from TAPPI standard conditions (dry) to over 60% moisture content (saturated). Unbleached hard-wood and softwood fiber from full-scale kraft pulp production were used. The softwood fiber was refined using a Valley beater to reduce freeness. Handsheets were made with a blend of hardwood and softwood and with refined softwood, without the addition of wet-end chemistry. \u0000The resulting grams-force tear data obtained from the test was indexed with basis weight and plotted versus both moisture content and dryness. As moisture content levels in the handsheets increased, the wet tear strength also increased, reaching a critical maximum point. This marked a transition point on the graph where, beyond a critical moisture content level, the tear strength began to decline linearly as moisture increased. This pattern was repeated in handsheets made from a blend of hardwood and softwood and from 100% refined softwood.","PeriodicalId":436878,"journal":{"name":"January 2021","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130798217","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":"Spraying starch on the Fourdrinier— An option between wet end starch and the size press","authors":"Cole Price, M. Hubbe","doi":"10.32964/tj20.1.21","DOIUrl":"https://doi.org/10.32964/tj20.1.21","url":null,"abstract":"Technology to apply suspensions of starch grains to the wet surface of paper, during the dewatering process, is reviewed. Though the technology is not new, it continues to attract the attention of papermakers as a means to increase bonding strength. Starch grains that are sprayed onto the wet-web of paper can be retained at levels exceeding what can be effectively added to the fiber suspension at the wet end. Unlike adding a starch solution at a size press, no additional drying capacity is required on the paper machine. To be effective, the starch needs to be able to swell and develop bonding during the paper drying process. Paperboard applications with recycled fibers appear to be a good fit. There is potential to increase bonding by processes that favor fuller gelatinization of the starch grains by the time the paper becomes dry.","PeriodicalId":436878,"journal":{"name":"January 2021","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124994137","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":"Social Network Mental Disorders Detection via\u0000Online Social Media Mining","authors":"Prof. Narinder Kaur and Lakshay Monga","doi":"10.46501/ijmtst0701006","DOIUrl":"https://doi.org/10.46501/ijmtst0701006","url":null,"abstract":"Social Network Mental Disorder Detection” or “SNMD” is an approach to analyse data and retrieve sentiment\u0000that it embodies. Twitter SNMD analysis is an application of sentiment analysis on data from Twitter\u0000(tweets), in order to extract sentiments conveyed by the user. In this paper, we aim to review some papers\u0000regarding research in sentiment analysis on Twitter, describing the methodologies adopted and models\u0000applied, along with describing a generalized Python based approach. A prototype system is developed and\u0000tested.","PeriodicalId":436878,"journal":{"name":"January 2021","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124505448","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":"RFID Based Attendance System","authors":"Ajay Joshi, Aman Saxena, Poonam Juneja","doi":"10.46501/ijmtst0701009","DOIUrl":"https://doi.org/10.46501/ijmtst0701009","url":null,"abstract":"RFID is an acronym for “radio-frequency identification” RFID technology is an automatic wireless\u0000identification system that works by the help of two components: a card and a reader. Using the RFID\u0000technology, the conventional system of taking attendance can be completely transformed to be more in line\u0000with strides in digitalization. This system will help the authorities manage the attendance system in a more\u0000methodical, efficient and time saving manner. The proposed system has been implemented through a\u0000prototype that has proved the effectiveness of the concept in easing the logistics of taking attendance as a\u0000result of the automation due to the use of the RFID technology. The design of the system is simple, cost\u0000effective and agile making it a good candidate for commercial and academic purposes.","PeriodicalId":436878,"journal":{"name":"January 2021","volume":"46 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128748951","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":"Use of P for three potato clones in soil and in soilless cultivation","authors":"D. Sausen, I. Carvalho, M. Schorr, Miriam da Silva Tavares, A. S. Pereira, A. O. S. Dorneles, D. Bernardy, F. Lautenchleger, D. Bisognin, F. Nicoloso","doi":"10.21475/AJCS.21.15.01.2816","DOIUrl":"https://doi.org/10.21475/AJCS.21.15.01.2816","url":null,"abstract":"The objective of this work was to verify the nutritional efficiency to phosphorus (P) as well as the responses of the use of P for three potato clones in soil and soilless cultivation (semi hydroponic). For this purpose, the Asterix, SMIC 148-A and SMINIA 793101-3 clones were evaluated under high and low P levels in soil growing (70 and 560kg P2O5 ha-1) and in soilless cultivation using sand as substrate (2.32 and 23.2mg P L-1 of nutritive solution). Rooting efficiency, absorption, translocation and use of P, fresh tuber mass, total dry mass and harvest index were evaluated in the clones. Each clone responds differently to the growing systems used in terms of nutritional efficiency for P. In both growing systems, the Asterix, SMIC 148-A and SMINIA 793101-3 clones did not show any increase in the absorption efficiency and in the efficiency of using P to compensate for the low level of P, which may have caused the reduction in total dry mass under low P. The restriction of P causes a reduction in tuber fresh mass for the Asterix and SMINIA 793101-3 clones in the two growing systems tested and for the SMIC 148-A clone only in soilless cultivation. Asterix is the clone with the highest harvest index under low P in the field, even without differing from the others in soilless cultivation","PeriodicalId":436878,"journal":{"name":"January 2021","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122071812","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":"The potential of nutrient cycling in cover plants in response to phosphate fertilization","authors":"É. Araújo, Vitório Macieski Neto, José Vanor Felini Catânio, R. Silva, Nélio Ranieli F. Paula, D. Freitas, Jiovane Anderson da Silva Ribeiro, Daniele Jesus Venturim","doi":"10.21475/AJCS.21.15.01.2923","DOIUrl":"https://doi.org/10.21475/AJCS.21.15.01.2923","url":null,"abstract":"Residues of crops and cover crops contain considerable amounts of phosphorus (P) in their tissues, which through their mineralization can meet much of the requirement of crops. In this context, the present study aimed to evaluate the biomass production, P absorption and use of different cover crops subjected to phosphate fertilization, and its effects on the absorption and use of nitrogen (N), phosphorus (P) and potassium (K). The experiment was conducted in a protected environment from August to December 2019. The experimental design was completely randomized, arranged in a 7 x 3 scheme, consisting of the planting of seven species of cover crops (Crotalaria spectabilis, Crotalaria breviflora, Crotalaria ochroleuca, Mucuna aterrima, Mucuna pruriens, Dolichos lablab and Canavalia ensiformis), three P rates (0, 80 and 160 kg ha-1 of P2O5) and four replicates. At the time of full flowering, the cover species were cut and divided into root and shoot for subsequent determination of dry mass production, nutrient content and absorption efficiency and nutrient utilization. The results showed that Canavalia ensiformis promoted higher yield of shoot fresh and dry mass, P content in the shoots and higher N and P absorption efficiency. N and P contents in Dolichos lablab roots were higher at the highest P rates (160 kg ha-1 of P), without close relationship with the supply of shoot dry mass. The P dose of 160 kg ha-1 had an increasing and significant effect on the production of shoot fresh mass and dry mass, N, P and K contents in the shoots, N, P and K contents in the roots and efficiency of N, P and K use by the different cover crops. The P rates of 80 kg ha-1 increased the N, P and K contents in the shoots of Crotalaria ochroleuca, Crotalaria breviflora and Crotalaria spectabilis; and at higher P rates, there was a reduction in nutrient accumulation. The species Mucuna pruriens and Mucuna aterrima were efficient in the use of N, P and K at P rates of 160 kg ha-1.","PeriodicalId":436878,"journal":{"name":"January 2021","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126664093","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}