Structural effects of glycol and benzenedicarboxylate units on the adhesion of water‐soluble polyester sizes to polyester fibers

The adhesion of water‐soluble polyester (WSP) sizes to polyester fibers was investigated to reveal the relation between the functions of glycol and benzenedicarboxylate units in WSP macromolecules and the adhesion in order to improve the performance of WSP in warp sizing. Serial WSPs with the variation in both glycol and benzenedicarboxylate structures were synthesized through a two‐step reaction: transesterification and polycondensation. The adhesion was evaluated in terms of tensile strength and work‐to‐break using a slightly sized polyester roving method. The adhesion depended markedly on the structures of glycol and benzenedicarboxylate units. The decrease in the length of glycol unit enhanced the adhesion. With the increase in the amount of dimethyl isophthalate‐5‐sodium sulfonate (SIPM), the adhesion initially increased and then decreased while the amount of dimethyl isophthalate (DMI) appreciably affected the adhesion. Suitable monomers for the preparation of the sizes were ethylene glycol, dimethyl terephthalate (DMT), DMI, and SIPM. To achieve maximum adhesion, the proportion of benzenedicarboxylate monomers in molar ratio should be about 64(DMT)/11(DMI)/25(SIPM). The adhesion of the WSP thus produced to polyester fibers is similar to that of polyacrylates, but better than that of PVA.     

Study on dyeing and fastness properties of wool–polyester blend fabrics using novel mono azo-naphthalimide dyes

The objective of the research reported in this paper was to investigate the determinants of textile-export performance by using data for major textile-exporting countries. Gross exports and net exports were the two measures of export performance. Multiple-regression analysis was used to investigate the relationship between export performance and a country's resource endowments (physical capital, technological capital, human capital) and industry characteristics (unit labor costs, domestic-apparel production). Cross-section data for 1970, 1975, 1980, and 1985 were used in the analysis. Major findings indicated that countries with more physical capital were more likely to be gross or net textile exporters, whereas countries with higher levels of human capital and more domestic-apparel production were less likely to be gross or net textile exporters. The impact of technological capital varied according to whether a country was a gross or net textile exporter.     

Environmental friendly carrier preparation and its application in one-bath dyeing of wool/polyester fabric北大核心

In order to decrease polyester dyeing temperature, and realize one-bath dyeing of wool, polyester blended fabric, environmental friendly inodorous carrier emulsion with good stability was preparation, the effects of carrier on polyester glass transition temperature, dyeing temperature and carrier amount on polyester dyeing performance were investigated, and solving method of disperse dye staining wool after one-bath dyeing of wool and polyester was discussed. The results showed that carrier had obvious plasticizing effect, polyester can be dyed at 98 °C by using the carrier, the optimum carrier amount was 5% (owf). After one-bath dyeing of wool and polyester, reduction cleaning at 75 °C for 10 min with bath ratio 1 = 50 by using solution containing sodium hydrosulfite 0.6 g/L, sodium carbonate 1.0 g/L, and anionic surfactant AES 1. 0 g/L, which could solve the problem of disperse dye staining wool.     

Stability of blueberry (Cornus mas – Yulyush) anthocyanin pigment under pH and co-pigment treatments

In this study, the effects of different pH values and co-pigments, including tannic, caffeic, benzoic, and coumaric acids, in various concentrations on anthocyanin co-pigment complexes (ratio 1:1) were investigated. The anthocyanin was extracted from a round sweet variety of blueberry and subjected to the highest co-pigment concentration (960 mg/l) at different pH values. The results showed that caffeic acid produced the highest stability of anthocyanin compared to the other co-pigments. In addition, benzoic acid had the lowest hyperchromic and bathochromic changes. A positive correlation was found between the co-pigment concentrations and the stability of anthocyanin as well as hyperchromic and bathochromic changes. The results also demonstrated that higher pH values resulted in further destruction of anthocyanin. Furthermore, the absorption rate of anthocyanin in the anthocyanin–co-pigment complex within lower pH values was more compared with the higher ones. The strongest hyperchromic and bathochromic effects for all organic acids were observed in pH values 1 and 4, respectively. It can be concluded that among the tested co-pigments, caffeic acid was the best co-pigment, while benzoic acid was the weakest, which was not suitable for anthocyanin in the round sweet variety of blueberry.     

Electric field effects on β-lactoglobulin thermal unfolding as a function of pH – Impact on protein functionality

The presence of moderate electric fields (MEF) during ohmic heating (OH) treatment of whey protein systems have demonstrated potential to change physicochemical and functional properties, like aggregation rate and extension or viscoelastic behaviour. However, the specific action of MEF upon the molecular structure of proteins, particularly during thermal processing has yet to be clarified. The effects of MEF in pure fractions of β-lactoglobulin (β-lg) under non-aggregating conditions (low concentration and ionic strength), were investigated in this work. Protein samples were identically heat-treated through conventional and OH methods and at different pH values. β-lg's structural features were characterized by evaluation of secondary structure distribution and local conformational changes using techniques such as circular dichroism, intrinsic and extrinsic fluorescence and free thiol groups reactivity. It was confirmed that MEF affects β-lg upon thermal unfolding, resulting in distinctive structural features, surface hydrophobicity and SH reactivity. The mechanism of action is probably related with the molecular motion induced by the oscillating electric field and is more pronounced at neutral pH, where β-lg is more susceptible to thermal structural changes. These results contribute to a better understanding of OH processing and its effects in food matrices reinforce the possibility of using MEF as a toll to change protein functionality.Industrial relevanceOhmic heating is an emerging technology and is being established as reference method for processing protein-rich food such as dairy and egg products. Non-thermal effects of the applied electric fields during ohmic heating have been addressed but few works deal with their real impact in structural and molecular properties of food proteins with high biological value.In this work demonstrated that the presence of an electric field during ohmic heating processing influences structural aspects of beta-lactoglobulin. This knowledge plays an important role on process design (i.e. pasteurization binomials and fouling control) and product quality because these proteins play an essential role in food's nutritional and organoleptic properties, as well as on functionality, allergenicity and stability aspects.     

Moisture-induced aggregation of alpha-lactalbumin: effects of temperature, cations, and pH

Abstract: Alpha‐lactalbumin is an important dairy protein ingredient, and has been widely used in high‐protein foods such as infant formula and nutritional bars for its nutritional and functional properties. The purpose of this study was to investigate the moisture‐induced aggregation of alpha‐lactalbumin in premixed protein dough model systems, and to illustrate the effects of temperature, cations, and pH on the progress of protein aggregation. Our results suggested that storage temperature was a critical factor for protein aggregation in model systems, and the formation of protein aggregates became faster with increases in storage temperature. Calcium significantly improved the thermal stability of alpha‐lactalbumin and slowed down the formation of protein aggregates. The increases in pH accelerated the aggregation of alpha‐lactalbumin. Our results also suggested that the formation of intermolecular disulfide bonds together with noncovalent interactions are the main mechanisms resulting in the moisture‐induced aggregation of alpha‐lactalbumin in model systems. Practical Application: Alpha‐lactalbumin is an important dairy protein ingredient, and has been widely used in high‐protein foods such as infant formula and nutritional bars for its nutritional and functional properties. Our results suggested low storage temperature, the presence of calcium and low pH condition can make high‐protein food products containing alpha‐lactalbumin more stable.     

PET瓶回收(洗涤)

介绍了意大利Sorema公司提供的PET瓶回收技术.描述了再生PET瓶片的规格和用于纤维生产的PET瓶洗涤装置.分析了回收的工艺成本.     

Unraveling the nature of ohmic heating effects in structural aspects of whey proteins – The impact of electrical and electrochemical effects

Electric field (EF) variables and electrode material are fundamental factors in ohmic heating (OH) processing. In this study, stainless steel, titanium and graphite were used as electrodes in conventional and OH (at 50 Hz and 20 kHz) treatments of whey protein isolate solutions at pH 3 and pH 7. The treated solutions were characterized in terms of UV absorbance, changes in intrinsic fluorescence, binding of a conformational probe and secondary structure (evaluated by circular dichroism). Differentiated structural features were induced by the different treatment conditions and were more evident at pH 7 and OH at 50 Hz. The metal leakage (quantified with ICP-MS) from the electrodes revealed to influence the equilibrium of early stages of protein aggregation, with stainless steel demonstrating to be the most electro-active material followed by titanium and finally graphite (that did not release metal). These findings highlight that structural properties of whey proteins may not only be influenced by the EF action but also by the leakage of metals from the electrodes.Industrial relevanceOH is a recognized emerging processing technology and has a recognized potential to control and enhance protein functionality due its ability to influence protein structural features. Both electrode stability and protein structural changes are related with the EF operational parameters such as voltage, current or frequency. These parameters are decisive in the occurrence and extension of electrochemical phenomena and in the EF action mechanisms over protein structure. The confirmation of EF non-thermal effects at high and low frequencies (independently of the electrochemical phenomena) dissipated previous doubts regarding its effectiveness to modulate protein functionality. The understanding of the electrode material stability and influence of different electric parameters on the product's functionality, stability and safety are fundamental to design OH devices and to the establishment of operational protocols. The stability and material release from the electrodes is a fundamental factor during OH processing, imposing serious implications in equipment costs, maintenance, as well as in product quality and safety. This study highlights the influence of different electrode materials during OH at different electrical frequencies and its impacts on protein structural aspects.     

Properties of (Ni-P)–SnO2 (nanometer) electroless composite coating on PET fabrics

The preceding parts of this series detailed a theoretical analysis to predict fabric tensile behaviour, the measurement and mathematical representations of the fibre-orientation angle and curl factor, which are the two principal parameters involved in the treatment, and a complete list of variables essential for computations and procedures to determine their values. This paper presents a comparison of the predicted stress–strain curves, constructed from the computer calculations, and the experimental ones for the nine commercial fabrics studied. After the individual remarks concerning the outcome for each fabric, possible reasons for the discrepancies encountered between the theoretical and experimental curves and the validity of some assumptions made in the analysis are discussed.     

PET的高速纺丝(上)

引言本文根据PET熔纺的理论模型,讨论了实验结果。模型是以质量平衡、力学、运动学和固化动力学为基础,方程的解只限于纺程上的拉伸区,一般的模型与实验测定某些函数,例如纺程上的直径d(x)、温度T(x)和双折射△n(x),能很好相吻合。从连续运动方程和一般粘弹方程可以得到速度v(x),     

Manipulating effects of fruits and vegetables on gut microbiota – a critical review

The objective of the current review was to systematically investigate health-promoting manipulating effects of fruits and vegetables (F&V) on the gut microbiota. The function of gut microbes was found to promote health effects in the host by scavenging free radicals, modulating immune system, alleviating obesity and diabetes. Masters that manipulate the gut microbiota are the phytochemicals within specific types of F&V, where polyphenols account for the largest proportion, along with alkaloids, terpenes, nitrogen-containing compounds, polysaccharides and natural pigments present in plants. These bioactive compounds exhibit the regulative influences on gut microorganisms characterised by rescuing dysbiosis of gut microbiota, increasing/decreasing microbial abundance, restructuring microbial composition, and rebalancing gut microbial homeostasis. This review indicated that F&V extracts targeting at gut microbiota could be a new scope of ingredient selection in the field of functional food especially for amelioration of dysfunction of intestinal ecosystem.     

聚酯(PET)饮料瓶卫生标准的研制

本文调查了广西从西德和日本引进的四条聚酯(PET)饮料瓶生产线,抽检了90件样品,测定蒸发残渣,高锰酸钾消耗量、重金属、锑、镉和脱色试验等项目,参考了国内外有关资料,提出聚酯(PET)饮料瓶的卫生标准建议稿为:     

pH实际意义和控制方法(下)

控制温度过程中染料吸尽速率主要是决定于时间——温度曲线,即升温速率,特别是超过临界温度范围后,以及在最高温度保持的时间[图1(a)和1(c)]。染浴中加入酸或碱与适当的盐和助剂在一起,会改变温度曲线的影响,染浴pH值大大影响染料吸尽速率。例如,用耐缩绒酸性染料染羊毛或锦纶纤维在pH值2.5,而不是通常的5.5左右,将导致很不均匀地吸附,由于这些染料阴离子亲和力高将难于纠正不匀性。因此,所需的pH值是由染料和纤维二者的化学性质以及以后它们之间发生的相互作用来决定的。换句话说,染浴pH值的选择是决定于     

pH实际意义和控制方法(上)

引言发生在水溶液环境中并包含有氢或氢氧离子的化学反应可以通过仔细地改变这二种离子的浓度来控制。这样,在分子中适当的基团的离解或结合的情况下,通过增加或减小氢离子浓度可使下面的平衡移向左面或右面:     

Phenotypic effects of subclinical paratuberculosis (Johne’s disease) in dairy cattle

The effect of subclinical paratuberculosis (or Johne’s disease) risk status on performance, health, and fertility was studied in 58,096 UK Holstein-Friesian cows with 156,837 lactations across lactations 1 to 3. Low-, medium-, and high-risk group categories were allocated to cows determined by a minimum of 4 ELISA milk tests taken at any time during their lactating life. Lactation curves of daily milk, protein, and fat yields and protein and fat percentage, together with log_e-transformed somatic cell count, were estimated using a random regression model to quantify differences between risk groups. The effect of subclinical paratuberculosis risk groups on fertility, lactation-average somatic cell count, and mastitis were analyzed using linear regression fitting risk group as a fixed effect. Milk yield losses associated with high-risk cows compared with low-risk cows in lactations 1, 2, and 3 for mean daily yield were 0.34, 1.05, and 1.61 kg; likewise, accumulated 305-d yields were 103, 316, and 485 kg, respectively. The total loss was 904 kg over the first 3 lactations. Protein and fat yield losses associated with high-risk cows were significant, but primarily a feature of decreasing milk yield. Similar trends were observed for both test-day and lactation-average somatic cell count measures with higher somatic cell counts from medium- and high-risk cows compared with low-risk cows, and differences were in almost all cases significant. Likewise, mastitis incidence was significantly higher in high-risk cows compared with low-risk cows in lactations 2 and 3. Whereas the few significant differences between risk groups among fertility traits were inconsistent with no clear trend. These results are expected to be conservative, as some animals that were considered negative may become positive after the timeframe of this study, particularly if the animal was tested when relatively young. However, the magnitude of milk yield losses together with higher somatic cell counts and an increase in mastitis incidence should motivate farmers to implement the appropriate control measures to reduce the spread of the disease.     

pH电极和DO(溶解氧)电极

ＧＫＦｐＨ电极和ＤＯ电极是我所科技项目成果产品。ｐＨ电极曾获“七五”攻关重大科技成果奖、中国科学院进步奖二等奖。它们能广泛应用于制药、味精、食品发酵、石油、血制品、化工等行业的在线检测 ,经上海技术监督局随机检测和华北制药厂 117车间 1996年试用结果表明 ,该产品性能指标和产品质量优良。主要技术指标有 :1.ｐＨ电级　测量范围 :ｐＨ 1～ 12灭菌温度 :10 5～ 150℃测量范围 :10～ 95℃插入深度 :12 5,150 ,180 ,2 0 0 ,2 50 (可根据客户要求特制 )安装方式 :通过护套与发酵罐连接或通过法兰与反应釜连接配套工业ｐＨ计 ,测…     

Evaluation of trigeminal pungency perception of allyl isothiocyanate – A time intensity (TI) study

Allyl isothiocyanate, the primary pungent substance within mustard, horseradish, and wasabi, causes a burning sensation and a lachrymatory effect during consumption. In this time intensity study, the sensory perception of the chemical stimulus allyl isothiocyanate was evaluated in water-based, oil-based, and mustard recipe-based carrier matrices. The results indicate that perceived pungency intensity and time course of perception were both strongly dependent upon allyl isothiocyanate concentration and the composition of the carrier matrices. Increasing allyl isothiocyanate concentrations led to a significant (p < 0.05) increase in maximum intensity of pungency (I_max) in all tested carrier matrices. The intensity of pungency perception for allyl isothiocyanate decreased depending upon the specific matrix used. Specifically, this decrease occurred in the order oil-based carrier < mustard-based carrier < water-based carrier at similar allyl isothiocyanate concentrations. The values for end time of pungency perception (T_End) and duration of decreasing phase (DUR_Dec) indicate that increasing allyl isothiocyanate concentrations prolong the duration of pungency perception. Allyl isothiocyanate was perceived longer in water than in oil- and mustard-based carrier matrices.     

Role of general stress-response alternative sigma factors σ(S) (RpoS) and σ(B) (SigB) in bacterial heat resistance as a function of treatment medium pH

This investigation aimed to determine the role of general stress-response alternative sigma factors σ^S (RpoS) and σ^B (SigB) in heat resistance and the occurrence of sublethal injuries in cell envelopes of stationary-phase Escherichia coli BJ4 and Listeria monocytogenes EGD-e cells, respectively, as a function of treatment medium pH. Given that microbial death followed first-order inactivation kinetics (R² > 0.95) the traditional D_T and z values were used to describe the heat inactivation kinetics.Influence of rpoS deletion was constant at every treatment temperature and pH, making a ΔrpoS deletion mutant strain approximately 5.5 times more heat sensitive than its parental strain for every studied condition. Furthermore, the influence of the pH of the treatment medium on the reduction of the heat resistance of E. coli was also constant and independent of the treatment temperature (average z value = 4.9 °C) in both parental and mutant strains.L. monocytogenes EGD-e z values obtained at pH 7.0 and 5.5 were not significantly different (p > 0.05) in either parental or the ?sigB deletion mutant strains (average z value = 4.8 °C). Nevertheless, at pH 4.0 the z value was higher (z = 8.4 °C), indicating that heat resistance of both L. monocytogenes strains was less dependent on temperature at pH 4.0. At both pH 5.5 and 7.0 the influence of sigB deletion was constant and independent of the treatment temperature, decreasing L. monocytogenes heat resistance approximately 2.5 times. In contrast, the absence of sigB did not decrease the heat resistance of L. monocytogenes at pH 4.0.The role of RpoS in protecting cell envelopes was more important in E. coli (4 times) than SigB in L. monocytogenes (1.5 times). Moreover, the role of σ^S in increasing heat resistance seems more relevant in enhancing the intrinsic resilience of the cytoplasmic membrane, and to a lesser extent, outer membrane resilience.Knowledge of environmental conditions related to the activation of alternative sigma factors σ^S and σ^B and their effects on heat resistance would help us to avoid and/or identify situations that increase bacterial stress resistance. Therefore, more efficient food preservation processes might be designed.     

国内最宽的聚酯(PET)热轧机

20 0 4年 1月 1 1日 ,浙江绍兴天鹏新纺材料有限公司从寇司德公司定购了 41 2 70型热均匀辊轧机。该轧机的辊宽为 5 60 0mm ,是中国同类产品中最宽的热轧机。该轧机装有 2 5 0℃热均匀辊 ,用于纺粘法生产聚酯 (PET)和聚丙烯 (PP)非织造材料 ,定量范围为 2 0～ 2 30 g/m2 。国内最宽的聚酯(PET)热轧机     

Sustainable (food) packaging – an overview

Packaging has an increasingly essential role to play in preserving the value invested in products by ensuring that they can deliver their designed service with minimum wastage. Food contact materials that deliver more units of service with increasingly fewer inputs of energy and materials, and increasingly fewer negative social, economic and environmental impacts, e.g., from emission of wastes, will be more sustainable both in the food processing machines of the industrial system and as packaging for food. Buzz words, whether bio-, nano-, degradable, or whatever comes next, must be critically examined per unit of service delivered to determine if, over the whole life cycle of the products to which they are applied, energy and resource use are minimised, pollution is reduced (not relocated), ecological benefits are created, and social and economic well-being are increased. Only when this caution is applied can a new solution be described as more sustainable.