Karakterizacija pulpe i papira izrađenih od stabljika bamije (Abelmoschus esculentus)

In this study, the usability of okra (Abelmoschus esculentus) stalks in pulp and paper production was investigated. Firstly, chemical components and fiber morphological properties were determined to investigate the suitability of okra stalks for pulp and paper production. Holocellulose, cellulose and lignin contents were found as 76.1 %, 46.4 % and 16.0 %, respectively and the fiber length, fiber width and cell wall thickness were measured as 0.64 mm, 16.97 μm and 3.66 μm, respectively. According to these data, it has been determined that okra stalks are suitable for pulp and paper production. Four different cooking experiments were carried out by adding sodium borohydride (NaBH4) in different proportions (0 %, 0.3 %, 0.5 %, 0.7 %) to okra stalks by the alkali sulfite method. The yield, chemical, physical and optical properties of the pulps were determined and optimum properties were obtained from the cooking experiment by adding up to 0.7 % NaBH4 into cooking liquor. With the addition of 0.7 % NaBH4, pulp yield, breaking length, and burst index increased about 7.73 %, 3.84 %, and 11 %, respectively. Consequently, it has been concluded that pulp produced from okra stalks can be used in the paper industry by blending with long or recycled fibers in certain proportions.U ovom je radu istraživana upotrebljivost stabljika bamije (Abelmoschus esculentus) za proizvodnju celuloze i papira. Radi ispitivanja prikladnosti stabljika bamije za proizvodnju celuloze i papira, najprije su određeni udjeli kemijskih komponenata i morfološka svojstva vlakana. Utvrđeni udjeli holoceluloze, celuloze i lignina iznosili su 76,1 %, 46,4 % i 16,0 %. Duljina vlakana, širina vlakana i debljina stanične stijenke bili su 0,64 mm, 16,97 μm i 3,66 μm. Prema tim podatcima utvrđeno je da je stabljika bamije pogodna za proizvodnju celuloze i papira. Zatim su provedena četiri različita pokusa kuhanja alkalno sulfitnim postupkom, uz varijabilni dodatak natrijeva borhidrida (NaBH4): 0 %; 0,3 %; 0,5 %; 0,7 % s obzirom na količinu stabljika bamije. Određeni su prinos pulpe, njezina kemijska, fizikalna i optička svojstva te su postignuta optimalna svojstva pulpe u procesu kuhanja uz dodatak 0,7 % NaBH4 smjesi kemikalija za kuhanje (bijeli lug). Uz dodatak 0,7 % NaBH4, prinos pulpe, duljina loma i indeks pucanja papira izrađenoga od vlakana bamije povećali su se za oko 7,73 %, 3,84 %, odnosno 11 %. Posljedično, zaključeno je da se pulpa proizvedena od stabljika bamije može upotrebljavati u industriji papira u određenim omjerima pomiješana s dugim ili recikliranim vlaknima

Çok kültürlü ortamda kültürel zekânın kültürlerarası duyarlılık üzerine etkisi: Portekiz örneği

Bireyler yabancı oldukları toplumlar içerisinde bulunduklarında veya farklı toplumlardan bireyler ile etkileşim halinde olduklarında farklı davranış biçimleri gösterebilirler. Bu bağlamda, iletişim sorunlarının önüne geçilebilmesi için farklı kültürleri tanıma ve o kültürün normlarına saygı duyma konusunda bir farkındalık oluşturulması gerekmektedir ki, bu farkındalık literatürde kültürler arası duyarlılık kavramı ile ifade edilmektedir. Kültürel etkileşimin gelişmesinde etkili olan kültürler arası duyarlılığın kişilerin belli yetkinliklerine bağlı olduğu bilinmektedir. Bu yetkinliklerden birisinin de kültürel zekâ olduğu değerlendirilmiştir. Bu bağlamda, tez çalışmasının amacı kültürel zekânın kültürler arası duyarlılık üzerindeki etkisinin araştırılması olarak belirlenmiştir. Araştırma kapsamında kültürel zekâ ve kültürler arası duyarlılık ölçekleri kullanılarak oluşturan anket Bahar 2019 döneminde Portekiz'de lisans veya lisansüstü eğitimine devam etmekte olan 182'si Erasmus deneyimine sahip, 217'si ise Erasmus tecrübesi yaşamamış olan toplam 399 öğrenciye uygulanmıştır. Toplanan veriler IBM SPSS Statistics 22 Programı kullanılarak analiz edilmiştir. Analiz sonucunda kültürel zekanın kültürler arası duyarlılık üzerinde istatistiksel açıdan anlamlı bir etkisi olduğu sonucuna ulaşılmıştır. Kültürel zekanın alt boyutlarının kültürler arası duyarlılık üzerindeki etkisi analiz edilmiş olup, kültürel zekanın yalnızca biliş alt boyutunun anlamlı etkisi olduğu sonucuna ulaşılmıştır. İlave olarak, araştırmaya katılan öğrencilerin kültürler arası duyarlılığım kabul etme ve uyum alt boyutlarının, kültürel zekanın ise biliş ve motivasyon alt boyutlarının Erasmus yapma durumuna göre farklılaştığı sonucuna ulaşılmıştır. Araştırma sonuçlarının, öğrencilerin kültürler arası duyarlılık seviyelerinin artırılması yönelik uygulamalar konusunda gerek öğrenciler gerek üniversite yönetimleri ve gerekse aileler için faydalı bilgiler sunacağı değerlendirilmektedir. Anahtar Kelimeler: Kültürel Zekâ, Kültürlerarası Duyarlılık, ERASMU

Procjena linter celuloze kao alternativne sirovine za proizvodnju upijajućeg papira

The study was carried out to evaluate Linter Cellulose (LC) as an alternative raw material for tissue paper production. Since LC is generally dark brown in color, it must be bleached before being used in tissue paper production. Bleaching process was applied to LC after impurities and oils were removed. LC was bleached in 9 different conditions with sodium hypochlorite (NaClO). The optical and physical properties of LC were measured in accordance with relevance standards in order to determine optimum bleaching condition. The best results in the optical properties were obtained by bleaching with 12 % NaClO. The whiteness, brightness, and yellowness values were found as 67.54, 64.39, and 6.20, respectively. The physical properties of bleached LC were not suitable for tissue paper production. For this reason, LC and wood fi bers (WF) were mixed at certain rates to produce tissue paper. The physical and optical properties of the paper obtained from the mixtures were analyzed to determine the optimum mixing ratio. The results showed that 40 % LC and 60 % WF mixtures can be used in tissue paper products. The important physical properties for tissue paper were Water Retention Value(WRV) and Water Absorption Time (WAT) and these values were found as 293.6 g·m-2 and 1.67 s. WRV and WAT of LC were found to be better than those of WF (267 g·m-2 and 2.62 s). As a result, when considering the shortage of pulp and paper raw material, the use of LC in tissue paper production would contribute signifi cantly to procuring the raw material and providing economic production.Istraživanje je provedeno radi procjene linter celuloze (LC) kao alternativne sirovine za proizvodnju upijajućeg papira. Budući da je LC tamnosmeđe boje, prije uporabe za proizvodnju upijajućeg papira potrebno ga je izbijeliti. Procesi izbjeljivanja LC-a primijenjeni su nakonuklanjanja nečistoća i ulja. LC je izbijeljen natrijevim hipokloridom (NaClO) pri devet različitih uvjeta. Izmjerena su optička i fizikalna svojstva LC-a u skladu s odgovarajućim standardima kako bi se odredili optimalni uvjeti izbjeljivanja. Najbolji rezultati optičkih svojstava dobiveni su izbjeljivanjem 12-postotnim NaClO. Vrijednost bjeline iznosila je 67,54 %, sjajnosti 64,39 % i žutila 6,20 %. Fizikalna svojstva izbijeljenog LC-a nisu prikladna za proizvodnju upijajućeg papira. Stoga je LC pomiješan s drvnim vlakancima (WF) u određenom omjeru kako bi se dobila sirovina prikladna za proizvodnju upijajućeg papira. Fizikalna i optička svojstva papira proizvedenoga od pripremljene smjese analizirana su radi određivanja optimalnog omjera miješanja LC-a i WF-a. Rezultati su pokazali da je smjesa od 40 % LC-a i 60 %WF-a može upotrebljavati za izradu proizvoda od upijajućeg papira. Važna fizikalna svojstva upijajućeg papira jesu sposobnost zadržavanja vode (WRV) i vrijeme upijanja vode (WAT). Za proizvedeni upijajući papir izmjerena je vrijednost WRV-a od 293,6 g·m-2 i WAT-a od 1,67 s. Utvrđeno je da su vrijednosti WRV-a i WAT-a za LC bolje nego vrijednosti za WF (267 g·m-2 i 2,62 s). Kada se uzme u obzir nedostatak sirovine za proizvodnju celuloze i papira, može se reći da bi upotreba LC-a za proizvodnju upijajućeg papira mogla znatno pridonijeti lakšoj nabavi sirovina i ekonomičnosti proizvodnje

Utjecaj razlika između bjeljike i srži na mehanička svojstva drva brzorastućih vrsta

In most uses where wood material needs impregnation or dimensional stability is essential, the properties of sapwood and heartwood should be taken into account. Also, due to the structural differences between heartwood and sapwood, differences in the strength of wood materials should be predicted. Therefore, the aim of this study was to reveal the differences between the mechanical properties of sapwood and heartwood of some important fast-growing forest trees. For this purpose, two softwoods (Pinus sylvestris) and (Pinus brutia) and two hardwoods (Populus usbekistanica) and (Eucalyptus grandis) were selected as test trees. Compression strength parallel to grain (CS ǁ), static quality value (IS), bending strength (MOR), modulus of elasticity (MOE), tensile strength perpendicular to grain (TS⊥), shearing strength parallel to grain (SS ǁ), impact bending strength (IBS), dynamic quality value (ID) and Janka hardness values (JH) of sapwood and heartwood of test trees were determined in laboratory studies. The results of the t-test analysis showed that all mentioned mechanical properties of sapwood and heartwood of test trees were separated from each other as significant, except the shear strength of Eucalyptus, dynamic quality values of red pine and Scots pine and Janka hardness value of red pine. Finally, the results of the study revealed that the differences between sapwood and heartwood strength should be taken into account when wood species are used in constructions and other sensitive areas.U većini primjera uporabe drva u kojima je potrebna impregnacija ili je postojanost dimenzija iznimno važna treba uzeti u obzir različita svojstva drva bjeljike i srži. Usto, zbog strukturnih razlika između srži i bjeljike treba predvidjeti i razlike u njihovoj čvrstoći. Cilj je ovog istraživanja bio utvrditi razlike između mehaničkih svojstava srži i bjeljike nekih važnih brzorastućih šumskih vrsta drva. Stoga su za izradu uzoraka odabrane dvije vrste četinjača (Pinus sylvestris i Pinus brutia) i dvije vrste listača (Populus usbekistanica i Eucalyptus grandis). U laboratorijskim su uvjetima za uzorke drva četinjača i drva listača određena ova svojstva: tlačna čvrstoća paralelno s vlakancima (CS ǁ), vrijednost statičke kvalitete (IS), čvrstoća na savijanje (MOR), modul elastičnosti (MOE), vlačna čvrstoća okomito na vlakanca (TS⊥), smična čvrstoća paralelno s vlakancima (SS ǁ), čvrstoća drva na udarce (IBS), vrijednost dinamičke kvalitete (ID) i tvrdoća po Janki (JH). Rezultati usporedbe uz pomoć t-testa pokazali su da se istraživana mehanička svojstva drva bjeljike i srži znatno razlikuju, osim smične čvrstoće drva eukalipta, dinamičkih vrijednosti kvalitete drva crvenog bora i običnog bora te tvrdoće drva crvenog bora po Janki. Zaključno, rezultati studije pokazali su da je pri upotrebi drva brzorastućih vrsta u graditeljstvu i drugim osjetljivim područjima nužno uzeti u obzir razlike među mehaničkim svojstvima drva bjeljike i srži

Procjena mogućnosti uporabe biljaka Rhododendron luteum i Rhododendron ponticum kao sirovine za proizvodnju celuloze i papira

In this study, Rhododendron luteum and Rhododendron ponticum were evaluated as raw material for pulp and paper production. 12 different sodium borohydride (NaBH4) added cooking trials were performed for each sample and kraft method was used for pulp production. Pulp properties, such as yield, kappa number and viscosity, and physical properties, such as breaking length and burst index, were determined for each trial. Besides, the effects of active alkali and NaBH4 on the pulp and paper properties were also examined. Optimum cooking conditions were obtained by using 18 % active alkali for NaBH4-free cooking experiments and 0.5 % NaBH4 and 18 % active alkali for NaBH4-added cooking experiments. In NaBH4-added pulping condition, the screened yield, kappa number and viscosity of R. luteum were found to be 43.4 %, 40.1 and 949 cm3/g1, respectively. The respective values for R. ponticum were 41.9 %, 44.5 and 885 cm3/g1. The screened yields of R. luteum and R. ponticum increased by about 2.8 % and 5.3 %, respectively, with 5 % addition of NaBH4 compared to NaBH4-free cooking experiments. Furthermore, with the addition of NaBH4, the kappa numbers decreased while the viscosity increased. The physical properties of the produced papers were also improved by using NaBH4 in cooking liquor. According to the obtained results, it was found that R. luteum and R. ponticum species can be evaluated for pulp and paper production.U ovom je radu istražena mogućnost uporabe biljaka Rhododendron luteum i Rhododendron ponticum kao sirovine za proizvodnju celuloze i papira. Za svaki uzorak provedeno je 12 različitih ispitivanja kuhanja s natrijevim borhidridom (NaBH4), a celuloza je proizvedena kraft postupkom. Za svako ispitivanje određena su svojstva celuloze poput prinosa, kappa broja i viskoznosti, te fizička svojstva kao što su duljina lomljenja i indeks pucanja papira. Osim toga, ispitani su učinci aktivne lužine i NaBH4 na svojstva celuloze i papira. Optimalni uvjeti kuhanja postignuti su upotrebom 18 % aktivne lužine za eksperimentalno kuhanje bez NaBH4 i upotrebom 0,5 % NaBH4 i 18 % aktivne lužine za eksperimentalno kuhanje s dodatkom NaBH4. U proizvodnji celuloze iz biljke R. luteum s dodatkom NaBH4 utvrđeno je da prinos prosijavanja iznosi 43,4 %, da je kappa broj 40,1, a viskoznost 949 cm3/g, dok su vrijednosti za celulozu dobivenu iz biljke R. ponticum redom 41,9 %, 44,5 i 885 cm3/g. Prinos prosijavanja biljaka R. luteum i R. ponticum uz dodatak 5 % NaBH4 povećao se oko 2,8 % i 5,3 % u usporedbi s eksperimentalnim kuhanjem bez dodatka NaBH4. Nadalje, uz dodatak NaBH4 smanjuju se kappa brojevi, a viskoznosti se povećavaju. Fizička svojstva proizvedenih papira također se poboljšavaju dodavanjem NaBH4 tekućini za kuhanje. Iz dobivenih je rezultata utvrđeno da se biljke R. luteum i R. ponticum mogu upotrebljavati u proizvodnji celuloze i papira

Glyphosate reduced seed and leaf concentrations of calcium, manganese, magnesium, and iron in non-glyphosate resistant soybean

Greenhouse experiments were conducted to study the effects of glyphosate drift on plant growth and concentrations of mineral nutrients in leaves and seeds of non-glyphosate resistant soybean plants (Glycine max, L.). Glyphosate was sprayed on plant shoots at increasing rates between 0.06 and 1.2% of the recommended application rate forweed control. In an experiment with 3-week-old plants, increasing application of glyphosate on shoots significantly reduced chlorophyll concentration of the young leaves and shoots dry weight, particularly the young parts of plants. Concentration of shikimate due to increasing glyphosate rates was nearly 2-fold for older leaves and 16-fold for younger leaves compared to the control plants without glyphosate spray. Among the mineral nutrients analyzed, the leaf concentrations of potassium (K), phosphorus (P), copper (Cu) and zinc (Zn) were not affected, or even increased significantly in case of P and Cu in young leaves by glyphosate, while the concentrations of calcium (Ca), manganese (Mn) and magnesium (Mg) were reduced, particularly in young leaves. In the case of Fe, leaf concentrations showed a tendency to be reduced by glyphosate. In the second experiment harvested at the grain maturation, glyphosate application did not reduce the seed concentrations of nitrogen (N), K, P, Zn and Cu. Even, at the highest application rate of glyphosate, seed concentrations of N, K, Zn and Cuwere increased by glyphosate. By contrast, the seed concentrations of Ca, Mg, Fe and Mn were significantly reduced by glyphosate. These results suggested that glyphosatemay interfere with uptake and retranslocation of Ca, Mg, Fe and Mn, most probably by binding and thus immobilizing them. The decreases in seed concentration of Fe, Mn, Ca and Mg by glyphosate are very specific, and may affect seed quality

The incidence and distribution of anomalies found in the pregnant women applied to Kayseri City Hospital for obstetric ultrasound in 2019: a retrospective analysis

Objective Our aim is to determine the incidence and distribution of anomalies found in the pregnant women referred to the first obstetric radiology outpatient clinic of our hospital for ultrasound (US) examination in 2019. Methods A total of 5661 obstetric US examinations were performed in 4018 pregnant women, 588 of whom were foreigners, for routine control, follow-up and screening purposes between January 1 and December 31, 2019, and their results were analyzed retrospectively after obtaining the approval of ethics committee. All US examinations were conducted by a single radiologist (ŞT) with Canon Aplio 500 ultrasound device (Canon Medical Systems Corporation, Tokyo, Japan) using 3.5 Mhz convex probe. The results of the cases with anomalies were accessed and grouped systematically, and their incidence and distribution were reviewed by comparing with the literature. Results As a result of the reviewed obstetric US examinations, a total of 62 fetuses with anomalies, 17 of whom were from the foreign pregnant women, were found to have anomalies. Of these anomalies, 29 were craniospinal, 10 were genitourinary, 6 were cardiac, 6 were skeletal, 3 were gastrointestinal, 2 were thoracic and 6 were unclassified. The pregnant women were between 17 and 43 (27.5±7.21) years old and their weeks of gestation were varying between 11 and 39 (22.3±8.63) weeks. There were 8 (13%) pregnant women younger than 20 years old, 43 (69%) pregnant women between 20 and 35 years old, and 11 (18%) pregnant women older than 35 years old. Anomaly diagnosis was established during first trimester in 14 (22.5%) fetuses, 26 (42%) fetuses during second trimester, and 22 (35.5%) fetuses during third trimester. Conclusion We found in our study that the incidence of fetuses with congenital anomaly was 1.54% in total, 2.89% in foreigners and 1.31% in Turkish citizens. The most common anomaly is acrania with 7 (0.15%) cases, and the diagnosis was established during first trimester in six of them. Detailed fetal screening during first trimester is very important for the detection of non-chromosomal anomalies. However, second- and third-trimester examinations are also important for the accurate diagnosis in pregnancies without follow-up

Effects of sodium borohydride on peroxide bleaching of Pinus brutia Ten. and wheat straw pulps

The addition of sodium borohydride (NaBH4) to peroxide bleaching has been investigated for its effects on the bleaching yield, mechanical and optical properties of Pinus brutia and wheat straw pulps. The pulps were subjected to four different bleaching conditions by adding charges of NaBH4 at 0%, 0.5%, 1.0%, and 1.5%, while keeping a constant hydrogen peroxide charge of 7%. The use of NaBH4 in the peroxide bleaching processes of the two pulps increased the bleaching yields. The results show that the addition of NaBH4 significantly improved the mechanical properties of the pulps, including tensile and burst indices. The optical properties of the pulps were also improved with the addition of NaBH4. The increase in mechanical and optical properties can be attributed to the reduction of residual hydrogen peroxide and the removal of metal ions, while the decrease in yellowness is due to the removal of metal ions that can cause oxidative degradation of the pulp. The findings of this study suggest that the addition of NaBH4 as an additive in peroxide bleaching is a promising approach to improve the mechanical and optical properties of P. brutia and wheat straw pulps, which can be further explored in future research

Tunable gas permeation behavior in self-standing cellulose nanocrystal-based membranes

Biopolymers arise as environmentally benign alternatives to bio-accumulating, fossil resource-based synthetic polymers for a variety of applications, many of which require self-standing films or membranes. Novel sustainable amine-functionalized cellulose nanocrystals (CNCs) form dense films with low porosity suitable for gas barriers. Due to their brittleness, pure CNC membranes are challenging to work with but represent an attractive support material for selectivity-inducing additives. Supported ionic liquid membranes (SILMs) are promising due to their tunable properties and good performance in gas separation. In this study, we investigate the possibilities to realize such applications by applying glucose and ionic liquids (ILs) as additives with different functions in CNC-based membranes. By the choice of the plasticizer, the gas permeation behavior of the flexible self-standing films can be tuned from impermeable, using glucose as an additive, to permeable by addition of the ILs 1,3-dibutylimidazolium acetate and 1,3-ditetrahydrofurfurylimidazolium acetate. Tunability is also observed through the choice of the CNC source in the form of an inversed selectivity of the gas pair N2/O2, which was traceable to the CNCs’ source-specific properties. The contributions of the matrix and additive were analyzed by comparing CNC to chitosan membranes and considering gas solubilities and diffusivities. The obtained results underline the diversity and tunability of bio-derived functional materials.AB - Biopolymers arise as environmentally benign alternatives to bio-accumulating, fossil resource-based synthetic polymers for a variety of applications, many of which require self-standing films or membranes. Novel sustainable amine-functionalized cellulose nanocrystals (CNCs) form dense films with low porosity suitable for gas barriers. Due to their brittleness, pure CNC membranes are challenging to work with but represent an attractive support material for selectivity-inducing additives. Supported ionic liquid membranes (SILMs) are promising due to their tunable properties and good performance in gas separation. In this study, we investigate the possibilities to realize such applications by applying glucose and ionic liquids (ILs) as additives with different functions in CNC-based membranes. By the choice of the plasticizer, the gas permeation behavior of the flexible self-standing films can be tuned from impermeable, using glucose as an additive, to permeable by addition of the ILs 1,3-dibutylimidazolium acetate and 1,3-ditetrahydrofurfurylimidazolium acetate. Tunability is also observed through the choice of the CNC source in the form of an inversed selectivity of the gas pair Nsub>2/O, which was traceable to the CNCs’ source-specific properties. The contributions of the matrix and additive were analyzed by comparing CNC to chitosan membranes and considering gas solubilities and diffusivities. The obtained results underline the diversity and tunability of bio-derived functional materials

The usefulness of the Hounsfield unit and stone heterogeneity variation in predicting the shockwave lithotripsy outcome

PURPOSEThis study aimed to evaluate the use of stone density variation coefficient (SDVC) as an indicator of stone heterogeneity and previously reported parameters for predicting extracorporeal shock wave lithotripsy (ESWL) outcome in urinary calculi. Moreover, a new formula that could be used to predict ESWL success was suggested.METHODSA total of 850 patients, who underwent the first session of ESWL for urinary stones between 2015 and 2020, were examined, and 220 eligible patients were included in the study. Stone density variation coefficient and other parameters associated with stone attenuation values and stone size parameters were studied as potential predictors based on noncontrast com- puted tomography (NCCT). Extracorporeal shock wave lithotripsy success was considered after 3 months by radiography or NCCT. Logistic regression analysis was performed to determine the factors contributing to treatment success.RESULTSFor the 220 patients, ESWL success rate was 39.5%. The receiver operating characteristic analysis showed that SDVC (AUC=0.82; 95% confidence interval [CI]: 0.76–0.87; P < .001), mean stone density (AUC=0.81; 95% CI:0.75–0.87; P < .001), maximum stone density (AUC=0.70; 95% CI: 0.63–0.78; P < .001), stone volume (AUC=0.70; 95% CI: 0.62–0.77; P < .001), and major diam- eter (AUC=0.67; 95% CI: 0.59–0.74; P < .001) had significant prediction accuracy from high to low. Additionally, SDVC was found to be successful in predicting ESWL success, especially for patients with high mean stone density (OR = 10; 95% CI: 3.55–28.57; P < .001). The logistic regres- sion model, in which the “stone disintegration probability” (SDP) formula was found, correctly predicted ESWL success with a single session by 79.1%.CONCLUSIONIn conclusion, size and attenuation values were predictors of treatment success, and the best predictor was SDVC. Evaluation of SDP formula prior to ESWL could predict treatment outcomes and facilitate the decisions regarding treatment strategies