The biological effectiveness of wood modified with linear chain carboxylic acid anhydrides against Coniophora puteana

Pinus nigra Schneid) sapwood. A brown rot fungus [Coniophora puteana (Schum.:Fr)] was selected in order to determine and compare the effectiveness (threshold value) of the linear chain anhydrides. The work described in this paper has demonstrated that chemically modified Corsican pine sapwood afforded substantial bioprotection against Coniophora puteana. With all anhydrides studied, a weight gain of 18% following reaction ensured complete protection. The results indicate that degree of cell wall bulking by the bonded adduct, rather than extent of hydroxyl substitution is the primary factor controlling decay resistance.

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Biologische Wirksamkeit der Holzmodifikation mit Fetts?ureanhydriden zum Schutz gegen Braunf?ule (Coniphora puteana)

P. nigra Schneid .). Geprüft wurden die Anhydride von Essig-, Propion-, Butter-, Valerian- und Caprons?ure. Als Testpilz diente der Braunf?ulepilz Caniophora puteana (Schum. : Fr.). Die Ergebnisse zeigen eine erhebliche Verbesserung der biologische Resistenz gegen diesen Pilz nach der chemischen Modifizierung des korsischen Kiefernholzes. Mit allen Anhydriden konnte mit einem Massenzusatz von 18% ein vollst?ndiger Schutz erreicht werden. Die Ergebnisse deuten darauf hin, dass das Ausma? der Zellwandbelegung und nicht so sehr die Substitution der Hydroxylgruppen der ausschlaggebende Faktor zum Schutz vor biologischem Abbau ist.

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ANP would like to thank the State Scholarships Foundation of Greece for funds to conduct this research.     

Evaluation of thermally-treated wood of beech (Fagus sylvatica L.) and ash (Fraxinus excelsior L.) against Mediterranean termites (Reticulitermes spp.)

Termite resistance of thermally-treated ash (Fraxinus excelsior L) and European beech (Fagus sylvatica L) against subterranean termites (Reticulitermes banyulensis) was evaluated. A laboratory no-choice feeding test following the standard EN 177 was performed to assess the efficacy of this thermo-modification against subterranean termites in the Mediterranean area. After 8 weeks period of exposure, results showed that durability against termites was slightly improved for thermally-treated beech wood, which was classified as moderately durable. However, in case of thermally-treated ash wood, samples were highly biodegraded by termites, revealing no increase in their durability and being classified as non durable.     

Resistance of thermally modified ash (<Emphasis Type="Italic">Fraxinus excelsior</Emphasis> L.) wood under steam pressure against rot fungi,soil-inhabiting micro-organisms and termites

Thermal modification processes have been developed to increase the biological durability and dimensional stability of wood. The aim of this paper was to study the influence of ThermoWood^® treatment intensity on improvement of wood decay resistance against soil-inhabiting micro-organisms, brown/white rots and termite exposures. All of the tests were carried out in the laboratory with two different complementary research materials. The main research material consisted of ash (Fraxinus excelsior L.) wood thermally modified at temperatures of 170, 200, 215 and 228 °C. The reference materials were untreated ash and beech wood for decay resistance tests, untreated ash wood for soil bed tests and untreated ash, beech and pine wood for termite resistance tests. An agar block test was used to determine the resistance to two brown-rot and two white-rot fungi according to CEN/TS 15083-1 directives. Durability against soil-inhabiting micro-organisms was determined following the CEN/TS 15083-2 directives, by measuring the weight loss, modulus of elasticity (MOE) and modulus of rupture (MOR) after incubation periods of 24, 32 and 90 weeks. Finally, Reticulitermes santonensis species was used for determining the termite attack resistance by non-choice screening tests, with a size sample adjustment according to EN 117 standard directives on control samples and on samples which have previously been exposed to soil bed test. Thermal modification increased the biological durability of all samples. However, high thermal modification temperature above 215 °C, represented by a wood mass loss (ML%) due to thermal degradation of 20%, was needed to reach resistance against decay comparable with the durability classes of ‘‘durable’’ or ‘‘very durable’’ in the soil bed test. The brown-rot and white-rot tests gave slightly better durability classes than the soil bed test. Whatever the heat treatment conditions are, thermally modified ash wood was not efficient against termite attack neither before nor after soft rot degradation.     

Functional and biological activities of casein glycomacropeptide as influenced by lipophilization with medium and long chain fatty acid

This study determined the functional and different biological activities of casein glycomacropeptide (GMP) after conjugation with fatty acids. Medium (i.e. caproic, lauric and myristic acid) and long (i.e palmitic and stearic acid) fatty acids were conjugated to GMP at the available amino group. Functionalities of lipophilized GMP conjugates included foaming and emulsifying activities, and biological activities for bacterial growth inhibition, cell damage and anti-invasion. Greater lipophilization of GMP was achieved with medium chain fatty acids (p < 0.05), which resulted in reduced GMP solubility regardless of fatty acid conjugate. Foaming activity of GMP was lost after lipophilization, but emulsification activity of GMP was enhanced (p < 0.05). A parallel increase in growth inhibition of Salmonella spp. coupled with anti-invasion of Salmonella enteritidis (Inv A) into mammalian cells was induced by lipophilization of GMP with long chain fatty acid. Our results show that GMP modified by lipophilization with specific fatty acids provides improved functionality as a surfactant with enhanced antibacterial activity towards gram negative bacteria.     

铜氨改性柠檬酸交联棉织物的研究

采用柠檬酸交联棉织物,在此基础上,配制铜氨溶液对其进行整理,生成铜氨络合的柠檬酸交联棉织物。通过红外光谱分析其结构,并通过扫描电镜观察表面形态,对其抗菌性能、耐水洗性能、铜溶出含量进行了研究。结果表明,铜氨络合的柠檬酸交联棉织物具有良好的抗菌性、耐水洗性,而且铜离子溶出含量并不高。     

壳聚糖改性物对酸性染料絮凝性能的研究

在80℃搅拌10h条件下,2,3-环氧丙基三甲基氯化铵(EPTMAC)与壳聚糖反应可制备出不同规格的壳聚糖改性物.对壳聚糖改性物絮凝性能的研究结果表明:用不同规格壳聚糖改性物处理酸性蓝83,脱色率均在用量为10mg/L时出现峰值;用壳聚糖改性物(脱乙酰度DD=0.93,取代度DS=0.82)处理酸性蓝113、酸性蓝90时,120r/min搅拌5min后再以40r/min搅拌10min是最佳的搅拌方式,酸性蓝113、酸性蓝90的脱色率分别为92%、93%;壳聚糖改性物对酸性蓝83的絮凝效果优于对酸性蓝90.     

含硫吡咯基氨基酸化合物的合成表征及其与丙酮酸的反应

通过Paar-Knnor有机合成方法得到一种新的含硫吡咯基氨基酸化合物。此物质的结构类似于可能的大蒜绿变色素前体2-（3,4-dimethyl-1H-pyrrolyl）-3-methylbutanioc acid.（3,4-二甲基-1H-吡咯基）-3-甲基丁酸,简称为含硫吡咯基氨基酸,此物质与丙酮酸反应不能产生黄色素。丙酮酸是大蒜绿变过程中丙烯基半胱氨酸亚砜在蒜酶作用下的产物,先前合成的色素前体类似物与丙酮酸反应大多可以产生黄色素。研究表明,该中间体通过此途径与黄色素的产生无关。      

利用酸改性凹凸棒澄清葡萄酒的工艺研究

葡萄酒在酿造过程中出现的蛋白质会影响葡萄酒的品质.通过澄清工艺可以降低葡萄酒的蛋白质含量.凹凸棒石是一种较好的天然材料,其对物质的吸附能力较强.实验检验了不同种类的酸溶液对凹凸棒石改性后、不同浓度凹凸棒石悬浮液、澄清时间和温度的澄清效果,从而得出了相应的实验数据,这对于进行实际生产有较好的指导作用.     

Estimation of the biological value of food proteins by a modified equation of the essential amino acid index and the chemical score

A modified essential amino acid index equation incorporating a digestibility factor (MEAAI), and a chemical score index (CSI) were developed from the essential amino acid profile of 18 different food proteins hydrolysed by the combined but sequential action of papain and pronase E enzyme systems. The essential amino acid composition of whole egg was used as a reference standard. The following equations were proposed. In which a is the value of the limiting amino acid in the sample, and a_e is the corresponding value in whole egg. Both equations were used to calculate the biological value of different protein foodstuffs. There was a close agreement between values obtained using the equations and reported values for the same foodstuffs published in the literature. There was also a close correlation (r = 0.665) between data obtained using MEAAI and those obtained using CSI in estimating biological values, suggesting that either equation could be used reliably and solely to estimate protein biological value of foods.     

人造板车间刮板运输机断链、浮链故障产生原因及预防措施

对人造板生产中广泛使用的刮板运输机出现的断链和浮链故障产生的原因进行了分析,并提出了预防的措施.     

改性活性硅酸（PSA）的制备及其对印染废水处理性能的研究

以硅酸钠为原料制备活性硅酸[w(SiO2)为3%,pH=3,活化时间30～40 min],再加入n(Fe3 )/n(SiO2)为1.0的硫酸铁,陈化后即得改性活性硅酸.以弱酸性染料为模拟印染废水进行絮凝沉淀实验,在该絮凝剂用量8mg/100 mL,染液pH=7.5日寸静置1 h条件下,脱色率和COD.去除率可分别达到97.87%和98.28%.同样条件下,可测得此法对直接染料和活性染料也有很好的效果.     

The shelf-life of beef steaks treated with dl-lactic acid and antioxidants and stored under modified atmospheres

Beef steaks were treated with 1.5% lactic acid alone or supplemented with antioxidants (0.1% rosemary extract and 0.05% ascorbic acid). The steaks were stored under modified atmospheres containing either 60% O₂/40% CO₂ or 70% O₂/20% CO₂/10% N₂. Both the 40% CO₂ atmosphere and the lactic acid treatment significantly (P<0.05) inhibited growth of lactic acid bacteria, Brochothrix thermosphacta and Pseudomonas spp. Neither CO₂ in the pack atmosphere, treatment with lactic acid, nor a combination of both, affected formation of thiobarbituric acid reactive substances, myoglobin oxidation, or CIE a^* values. However, treatment with antioxidants significantly (P<0.05) delayed oxidation of both myoglobin and lipids, and so extended the storage-life.     

The optimization of the extrusion process when using maize flour with a modified amino acid profile for making tortillas

Maize with a modified amino acid profile, i.e. greater amounts of lysine and tryptophan than normal, is known as ‘quality protein maize’ (QPM). The objective of this work was to find the best combination of extrusion process variables to produce QPM flour for making tortillas. QPM grits were mixed with lime and water and had a moisture content of 28%. The single screw extruder operation conditions were selected from factorial combination of three process variables: extrusion temperature (ET, 70–100 °C), lime concentration (LC, 0.1–0.3% of the maize weight) and screw velocity (SV, 80–250 rpm). Response surface methodology was used as an optimization technique. In vitro protein digestibility (PD); total colour difference (ΔE) of the flours, and tortilla puffing (TP) were chosen as response variables. A graphical method was used to obtain maximum PD, TP and minimum ΔE. The optimum combination of process variables was: ET = 85 °C/LC = 0.21%(w/w)/SV = 240 rpm. Tortillas from QPM flour had similar chemical composition, physicochemical and sensory properties to tortillas from commercial nixtamalized maize flour; however, the former had the highest (P ≤ 0.05) available lysine content and were therefore better nutritionally.     

β-环糊精衍生物聚合物膜修饰电极对食品中抗坏血酸的测定

利用合成的β-环糊精(β-CD)的衍生物6-巯基-6-脱氧-β-CD在玻碳电极上制备聚合物膜(PTCD),用循环伏安法研究PTCD对抗坏血酸的电化学行为,实验结果显示,在pH6.5的磷酸盐缓冲溶液中,氧化峰电流与抗坏血酸浓度在5.0×10-5～1.5×10-3mol/L范围内成良好的线性关系,相关系数达0.9948,检测限为2.010-6mol/L。用于样品的测定,结果较令人满意。     

The potential of color measurements with the CIEDE2000 equation in wood science

This study seeks to assess the potential use of the CIEDE2000 color difference equation in wood science. Therefore, a set of oak wood samples were prepared and assessed by experts. The visual perception of the observers was correlated with the two different color difference equations CIELAB from DIN 6174 and the CIEDE2000 equation. For a practical example two different types of wood were bleached and exposed to UV-light. The results showed that the CIEDE2000 equation outperformed the CIELAB equation. The CIELAB equation showed generally an overestimation of the color change (ΔE) for wood applications, compared to the nontrivial CIEDE2000 equation from 2001.     

环保型生物蛋白改性助剂改性羊毛的染色性能

采用鸡毛蛋白改性助剂对羊毛纤维及其织物进行改性,研究改性羊毛兰纳素染料染色性能。结果表明,鸡毛蛋白改性助剂改性的羊毛纤维及其织物对兰纳素染料的染色性能改善明显,以固色率为测试指标优选的最佳染色工艺条件为:染料用量2%(owf),染色浴比1∶40,HAc用量0.5 mL/L,85℃染色50 min。同时,改性毛织物染色K/S值有所提高,匀染性较好。经鸡毛蛋白改性助剂改性的羊毛纤维和毛织物能够降低羊毛的染色温度,缩短染色时间,减少能耗,从而实现羊毛的低温染色。