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Studies on thermal characterization of lignin

Substituted phenol formaldehyde resin as wood adhesives

Journal of Thermal Analysis and Calorimetry
Authors:
M. Khan
and
S. Ashraf

Abstract  

Thermal properties of control phenol formaldehyde (cpf) adhesive and lignin substituted phenol formaldehyde (lpf) adhesives have been investigated in detail. The effect of varying lignin mass percent of phenol and source of lignin like bagasse, eucalyptus bark, coconut coirpith and coffee bean shell on the thermal stability have been studied using thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). 50 mass% of lignin loading in cpf adhesive shows better bond strength, whereas lignin incorporation up to 25 mass% yields a resin of thermal stability comparable to cpf. Loading of lignin in cpf delays the first thermal transition event. The mass loss in this event was found to increase with increasing lignin content. Lignin source has significant effect on the thermal stability of lpf resins. Rate of curing is enhanced by incorporation of lignin into cpf.

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Summary  

Many studies have shown that water hyacinth (Eichhornia crassipes) roots can be used to accumulate high concentrations of organic as well as inorganic pollutants. They are currently used to remediate aquatic environments and aqueous solutions. In the present study, sorption of uranium from aqueous solutions by using dried roots of water hyacinth has been investigated. The sorption of uranium was examined as a function of initial concentration, pH, weight of roots and contact time. Five different concentrations 20, 40, 60, 80, and 100 μg . ml-1 were used. Sorption proves to be very rapid and depend on pH, weight of roots and concentration of uranium. Maximum sorption capacity of water hyacinth roots was 64,000 U6+ μg/g. The sorption of uranium by water hyacinth roots follows a Langmuir isotherm.

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Abstract  

Water hyacinth (Eichhornia crassipes) is known to accumulate elements from rivers and a good tool for water monitoring. To test the usefulness of such an aquatic plant as a bioindicator, we have determined the levels of Na, Ca, Cr, Fe, Co, Zn, As, Rb, Zr, Sb, Cs, La, Ce, Nd, Sm, Eu, Tb, Yb, Hf, Ta, Th, and U in water hyacinth around industrial facilities and along the studied area by instrumental neutron activation analysis. The concentrations of Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Cd, and Pb were determined in upstream river water and effluent factories. Contamination factor, and pollution load index was calculated. The results show that higher concentrations as well as bioaccumulation factors of these elements were observed in water hyacinth samples around the industrial facilities. On the other hand a decrease in calcium concentration was observed as a result of the thermal pollution of Nile river water. The pollution load index for the studied area was estimated to be 4.2.

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This study investigated the diagnostic value of soluble urokinase plasminogen activator receptor (suPAR) and serum lactate in elderly patients with sepsis and evaluated their capacity to predict mortality and their correlation to Sequential Organ Failure Assessment (SOFA) score. The study included 80 participants, divided into two groups: 40 cases (mean age, 68.9 ± 5.9) admitted to the intensive care unit and 40 healthy controls (mean age, 67.1 ± 6.2). Elderly patients with sepsis had significantly higher levels of serum suPAR and lactic acid compared to healthy controls. Receiver operating characteristic (ROC) curve analysis showed that suPAR (cutoff value, ≥4.37 ng/ml) has higher area under the curve (AUC) than lactic acid (cutoff value, ≥1.95 mmol/l) for diagnosing sepsis. Serum lactate has superior prognostic value compared to suPAR with AUC of 0.82 (cutoff value, 2.2 mmol/l) and 0.72 (cutoff value, 6.3 ng/ml), respectively. The diagnostic power of combined usage of suPAR and lactate serum concentrations showed AUC of 0.988 (95% confidence interval 0.934 to 1.0). The combination of both biomarkers either together or with SOFA score may serve as a useful guide to patients who need more intensive resuscitation.

Open access

Abstract

The present manuscript demonstrates the work undertaken to optimise and validate a slow-release amylase-assisted extraction of polyphenols from peach fruit peel. A careful investigation and optimisation revealed that peach peel when hydrolysed with 1.50% (w/w) of SRA containing enzyme formulation at 40 °C and 6.1 pH, for 35 min significantly (P < 0.05) increased the extraction yield, levels of polyphenol contents (242.89 ± 1.56 mg gallic acid equivalents – GAE), and coumaric, chlorogenic, ferulic acids or their conjugate esters in extracts. Moreover, the extracts produced through SRA-assisted extraction exhibited ample level of free radical scavenging capacity (DPPH IC50 2.67 ± 0.03 μg mL−1), Trolox equivalent (TE) antioxidant capacity (450.52 ± 24.58 µmol of TE g−1), inhibition of peroxides in linoleic acid (85.68 ± 0.21%), and ferric reducing power of 3.11 ± 0.20 ppm gallic acid equivalents. The results suggested that the incorporation of SRA containing enzyme formulation may enhance the recovery of peach peel polyphenols while hydrolysing the glycosidic linkages without deteriorating their antioxidant character.

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Alkaline and acidic pH of soil limit crop yield. Products of phenylpropanoid pathway play a key part in plant abiotic stress tolerance. It was aimed to assess efficacy of tyrosinepriming for activation of enzyme involved in phenolic accumulation induction of pH tolerance in maize seedlings. Seeds of two maize cultivars, namely Sadaf (pH tolerant) and S-2002 (pH sensitive), were grown under three pH levels (3, 7 and 11). Eight and twelve days old seedlings were harvested and parted into roots and shoots for the assessment of growth, enzymatic and non-enzymatic antioxidants. PAL activity was directly correlated with total soluble phenolics, flavonoids, growth and seedling vigour. Lower accumulation of phenolics and PAL activity in the pH sensitive (S-2002) cultivar indicated greater oxidative damage caused by pH extremes. Priming improved antioxidative potential by enhancing PAL activity and phenolics accumulation and hence increased growth in maize seedlings.

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Abstract  

Transport of99mTc across tri-n-butylphosphate (TBP) kerosene oil supported liquid membranes (SLM) has been studied under various conditions. Presence of dichromate ions helps avoid activity scavenging effects. Concentration increase of TBP, the complexing carrier used in the present study has a positive effect on flux (J) and permeability (P) of these ions, as up to 2.87M there is an increase in J and P values. HCl concentration in the feed solution increases J and P with their maximum values at 2.5–3.0M HCl in the feed. Above this concentration there is a decrease in flux and permeability of99mTc(VII) ions. The given ions are stripped with LiCl or NaCl solutions but more with NaOH. The optimum conditions of transport of the given ions are 2.5M HCl concentration in the feed, 2.87M TBP concentration in the membrane and 1M NaOH concentration in the strip solution. Equations have been developed to indicate the relation between flux, J, viscosity, of TBP in organic membrane phase, temperature, T, [H+], in the aqueous feed solutions and Tc ion concentration in the feed solution. Based on P, the values determined from liquid membrane experiments, the quantitative flux values of Tc(VII) ions were also determined as a function of TBP concentration in the membranes, and HCl and Tc concentration in the feed solution using the given equations. This experimental technique provides quantitative results from trace level activity transfer experiments.

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Recently, super rice has gained much importance due to its high yield potential while exogenous application of plant growth regulators (PGRs) is an important aspect in plant development and defense responses under stress conditions. In this study we conducted two pot experiments. Firstly, four super rice cultivars, viz. Peizataifeng, Huayou 213, Yuxiangyouzhan and Huahang 31 were subjected to a series of five chilling temperatures, i.e. 11 °C, 12 °C, 13 °C, 14 °C and 15 °C (day/night) for about 25–27 days. Secondly, seeds of Peizataifeng (super rice) and Yuejingsimiao 2 (non-super rice) were then treated with different combinations of salicylic acid (SA), brassinolide (BR), calcium chloride (CaCl2) and fulvic acid (FA) and then exposed to chilling stress at 13 °C for four days. Resultantly, Peizataifen (super rice) was found with the lowest seedling survival rate at all chilling temperatures among all four super rice cultivars, however, it was still found more resistant when compared with Yuejingsimiao 2 (non-super rice) in the second experiment. Furthermore synergistic effect of all PGRs alleviated low temperature stress in both rice cultivars by improving seedling survival rates, leaf area, seedling dry weight, seedling height, root morphology and by modulating antioxidant enzymes, improving proline content and lowering lipid peroxidation.

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Orvosi Hetilap
Authors:
Attila Nemes
,
Marcel L. Geleijnse
,
Osama I. I. Soliman
,
Ashraf M. Anwar
,
Wim B. Vletter
,
Jackie S. McGhie
,
Miklós Csanády
,
Tamás Forster
, and
Folkert J. Ten Cate

A hypertrophiás cardiomyopathia egy relatíve gyakori öröklődő betegség, amely sajátos kardiális morfológiai és funkcionális eltérésekkel jár együtt. Az echokardiográfia a cardiomyopathiás betegek noninvazív vizsgálatának egyszerű, könnyen kivitelezhető és megtanulható módszereként szolgál. Ennek az összefoglaló jellegű közleménynek a célja az egyik legújabb echokardiográfiás fejlesztés, a real-time háromdimenziós echokardiográfia lehetséges diagnosztikus szerepének bemutatása hypertrophiás cardiomyopathiában.

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Orvosi Hetilap
Authors:
Attila Nemes
,
Marcel L. Geleijnse
,
Osama I.I. Soliman
,
Ashraf M. Anwar
,
Johan G. Bosch
,
Boudewijn J. Krenning
,
Sing-Chien Yap
,
Wim B. Vletter
,
Jackie S. McGhie
,
Tamás Forster
,
Miklós Csanády
, and
Folkert J. ten Cate

A kardiológiai betegek ellátásában a noninvazív vizsgáló módszereknek alapvető jelentőségük van. Elméletileg a szív akkor vizsgálható tökéletesen, ha természetének megfelelően három dimenzióban rögzítjük a szívciklus szerint. A második generációs, immár real-time (vagyis valós idejű) háromdimenziós echokardiográfok elméletileg optimális lehetőséget nyújtanak a cardialis struktúrák háromdimenziós elemzésére. Real-time 3-dimenziós echokardiográfia során pontosan mérhetők a kamrai és pitvari térfogatok, valamint a kamrai izomtömeg. A billentyűk és a congenitalis abnormalitások ‘en-face’ vizsgálhatók. Használhatóságát terheléses protokollok alkalmazása mellett igazolták. A jelen összefoglaló közlemény célja a módszer bemutatása, lehetséges előnyeinek tisztázása a jelenleg még fennálló technológiai korlátok bemutatásával együtt.

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