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Purpose The purpose of this study is to reveal the usability of waste paper sludge on the production of composite materials and the printability of their surfaces were investigated. Design/methodology/approach First, composite plates were produced by using dried and milled waste sludge together with polyester resin and epoxy. Screen printing using water, solvent and UV-based inks were carried out. Findings It was determined that UV and solvent-based inks in both resin groups were permanently attached to the surface of composite plates produced using paper mill waste sludge, while it was found that the adhesion was not achieved sufficiently in cardboard factory waste sludge. Originality/value The unique aspect of this study is obtained the composite plates from paper mill and cardboard mill waste sludge and improved the printability of them.

Dot gain is called Tone Value Increase (TVI). Low dot gain and rounder dot shape are important properties to obtain a good print. Dot gain is a measure of how much extra weight a given percent dot or tone has gained on the final printed substrate by comparison to the actual dot area on a press plate. Dot gain value depends on many factors. The interactions of paper, ink and press conditions are important determinates for a good print. In addition, the pigment coating process and calendering conditions have a significant effect on the printability of paperboards. Pigment coating formulations including mineral pigments, binders and additives improve the gloss, brightness, opacity and smoothness of the paperboards. As a result, print quality of paperboards increase. A uniform paperboard surface is needed to obtain a high quality surface smoothness after the coating process. High surface smoothness improves the uniformity of the dot shape and size. Pigment coating formulation parameters; pigment selection, binder selection and binder level influence print quality. The aims of this study - pigment selection and ratio - are to determine the effect on dot gain in lithography printing. To this aim, base paperboards were coated using five pigment coating formulations which included different combinations of kaolin, calcium carbonate and titanium dioxide pigment with a styrene\n-butyl acrylate copolymer binder using a bar application. After coating, the samples were air-dried overnight under TAPPI conditions. Then, half of the coated-paperboards were calendered. Tone scales from 1 to 100 % were offset printed using black ink on the uncalendered and calendered-coated paperboards. Then, from the printed tone scale, the tone area values were measured with the Gretagmacbeth Spectrolino spectrophotometer. These values showed that pigment coating improved the surface optical and physical properties of paperboards. After calendering, the roughness values of coated paperboards decreased. In addition, the obtained dot and line sharpness on calendered-coated paperboards were better than on uncalendered-coated paperboards. However, the dot gain values of calendered-coated paperboards had fewer dot gains than uncalendered-coated paperboards. It was established that the variation of pigment proportions in the coating formulations had no significant effect on dot gain. © 2019 Bulgarian Academy of Sciences, Union of Chemists in Bulgaria.

Köy Enstitüleri, dönemine göre ileri nitelikte bir eğitim kurumudur. Kuruluşundan önce birtakım köy okulları denemeleri yapılmıştır. Bunlar Eğitmen Kursları ve Köy Öğretmen Okullarıdır. Bu okullar daha sonraları Köy Enstitüleri bünyesine dahil edilmiştir. Köy Enstitüleri kurucusu İsmail Hakkı Tonguç, öncelikle Türkiye’nin köylerini gezerek ayrıntılı raporlar oluşturmuştur. Daha sonra yasa ile Köy Enstitüleri kuruluşu tamamlanmıştır. Her okulda okutulan derslerin yanı sıra tarım, marangozluk, inşaat gibi köyün ihtiyaçlarına yönelik dersler de verilmektedir. Köy Enstitülerinden mezun olan köy çocukları, yine kendi köylerine öğretmen olarak toplumsal kalkınmada rol üstlenmektedirler. Böylece köy öğretmenleri ile köyde eğitim ilerletilmektedir. Aynı zamanda köyün tüm ihtiyaçları giderilmeye çalışılmaktadır. Köylerde okuma-yazma bilmeyen çocuk kalmaması hedeflenmiştir. Ancak ileriki yıllarda Köy Enstitüleri dış konjonktürün de etkisiyle kapatılma sürecine girmiştir. Köy Enstitülerinin kapatılış nedenlerinden belki de en önemlisi komünistlik iddiasıdır. Bu iddiaların etkisi zamanla artmış ve yıkılışa neden olmuştur. Günümüzde ise ideolojik olarak halen etkisini sürdürmeye devam eden kurumlardır.

A cationic peroxidase gene (Shpx6a) of a forage legume species, Stylosanthes humilis, was transferred to poplar (Populus tremula) in antisense orientation under the control of 35S RNA promoter of cauliflower mosaic virus. Transformed plants were regenerated on selective media after co-cultivation of poplar stem explants with Agrobacterium tumefaciens and integration of transgenes was confirmed by PCR and Southern hybridization analyses. Analyses of selected transgenic plants showed reductions in total leaf peroxidase activity which was 50% to 70% of that measured in untransformed control plants. Transgenic poplar plants with reduced leaf peroxidase activity had 10-20% lower lignin content than control plants. Although which isoform of poplar peroxidase (s) has been inhibited by 35S-Shpx6a antisense construct is not clearly known, our results suggested the possibility of manipulation of lignin content through inhibition of lignin-specific peroxidases.

Plant regeneration from 9 clones ofPopulus tremula representing diverse genotypes originated from Turkey, has been studied in different media, such as Murashige and Skoog’s Medium (MS), Aspen Culture Medium (ACM) and Woody Plant Medium (WPM) with appropriate supplements of growth regulators. Regeneration efficiency on WPM containing 1 mg/l zeatin using stem explantsin vitro, was higher than on MS and ACM. In this system, the time required for shoot regeneration was 2 weeks, which was shorter by two weeks than that of previous reports. A strong genotype dependence was observed among the tested nine clones. The regeneration system, we describe here, did not involve the callus phase and thus was less prone to somaclonal variation. When adventitious microshoots were cultured on WPM supplemented with 0.5 mg/l or 2 mg/l indole-3-butyric acid (IBA), root formation was obtained after 1 week of culture. Adaptation of regenerated plantletsin vivo was 100%. This system for micropropagation ofPopulus tremula is expected to be suitable for studies on transformation of genes involved in lignin biosynthesis via modification of lignin content.

Tissue culture of Populus tremula Dursunbey 2 clone from stem expiants was established. peroxidase gene isolated from Stylosanthes humilis (Shpx6), in antisense orientation was transferred to poplar via Agrobacterium tumefaciens. The effects of Shpx6 gene leads to modification of total peroxidase activity and total lignin amount. A reduction of total peroxidase activity for 50% and total lignin amont for 20% was observed in transgenic plants compared with control plants. The results obtained here, could be useful for utilization of poplar in paper and pulp industry.

Populus tremula was transformed using Agrobacterium tumefaciens with antisens O-metyltransferase gene from Stylosanthes humilis (pOMT8), which is showing 83% homology with COMT gene from poplar. In four out of ten transgenic plants OMT activity has been downregulated for 30–39%, however peroxidase activity was 100% higher compared with controls. While the lignin amount in transgenic plants was not changed, lignin composition were modified. Results indicate that it is possible to downregulate endogenous OMT activity and modified lignin composition through the introduction of heterologous consract from Stylosanthes humilis in Populus tremula.