赋香型麦冬颗粒的制备及在卷烟滤棒中的应用

基于不燃烧调香的理念和麦冬的生物活性成分和口味特征,针对目前低焦卷烟风格特征弱化和感官舒适性下降等问题,通过流化床造粒工艺开发赋香型麦冬颗粒并进行滤棒添加应用实验。(1)利用响应面优化法,获得麦冬多孔颗粒的最佳工艺条件;(2)所制备的麦冬颗粒经粒径分析和结构表征,应用于卷烟滤棒改善抽吸舒适性,提升烟气在口腔中的津润感和甜感,有效降低主流烟气的燥热感,强化卷烟产品的清甜香风格特征;(3)采用HPLC-EIS/MS法,多反应监测模式(MRM)对烟气粒相物中的麦冬成分进行初步的定性分析。     

卷烟滤棒中三醋酸甘油酯含量的现场快速检测研究

为了提高卷烟滤棒中三醋酸甘油酯含量的检测效率,该文通过使用手持式近红外光谱仪,结合粒子群优化－极限学习机（PSO－ELM）回归算法建立了三醋酸甘油酯含量的定量预测模型,并与偏最小二乘回归（PLSR）和极限学习机回归（ELMR）进行了比较。实验结果表明：相比于PLSR和ELMR模型,所建立的PSO－ELM预测模型的决定系数R2为0.921 2,远高于PLSR预测模型的0.860 4和ELMR预测模型的0.877 2;同时,使用PSO－ELM模型的预测均方根误差（RMSEP）为0.392 12,小于PLSR预测模型的0.497 72和ELMR预测模型的0.470 18。以上实验结果表明,所建立的近红外光谱定量模型能够应用于卷烟滤棒中三醋酸甘油酯含量的快速准确测量,为实现滤棒中三醋酸甘油酯含量的现场快速检测提供了良好的技术参考。     

滤棒中线纤维化学特性对卷烟主流烟气有害成分释放量的影响

为了研究中线滤棒中线纤维化学特性对卷烟主流烟气中有害成分释放量的影响,采用Boehm滴定法及FT-IR光谱对纤维的基团及数量进行了分析,并结合烟气常规以及主流烟气有害成分释放量的检测探讨了纤维的化学特性与主流烟气有害成分释放量之间的相关性。结果显示：（1）卷烟主流烟气中NH。释放量随着纤维酸性基团数量的增加而降低;HCN释放量随着纤维碱性基团数量的增加而降低;（2）影响苯酚释放量的主要因素是纤维的内酯基,其次是纤维的酸碱性;（3）卷烟主流烟气中巴豆醛的释放量随纤维的氨基基团数量的增加而降低。     

气相色谱法测定醋酸纤维滤棒中薄荷醇

薄荷香料(包括薄荷油和留兰香油)是世界上第三大香料类型,其中主要的香气物质是薄荷醇。薄荷醇又称薄荷脑、六氢百里香酚,化学名为1-甲基-4-异丙基环己-3-醇,分子式为C10H20O,室温下为无色柱状或针状结晶体,暴露在空气中易升华,微溶于水,与乙醇和丙二醇可混溶[1-3]。卷烟中的薄荷味主要是香料添加而来,薄荷醇采用适当的缓释技术,适量加入到卷烟滤棒中,是薄荷型卷烟的重要生产途径之一[4-6]。     

高效液相色谱法测定卷烟醋酸纤维滤棒中甲醛、乙醛和丙酮的含量

建立了高效液相色谱法同时测定卷烟醋酸纤维滤棒中甲醛、乙醛和丙酮含量的方法,采用Acclaim(R)Explosive E2 C18色谱柱,流动相为乙腈/水梯度洗脱,流速为0.5 mL/min,检测波长为352 nm,对甲醛、乙醛和丙酮的分析取得满意的效果.甲醛、乙醛、丙酮的回收率分别为95.3％～105.6％、86.1...     

高湿模量纤维的研究——第一报甘蔗渣高湿模量纤维的研制

利用甘蔗渣作原料研制人造纤维解决穿衣问题,意义很大。目前粘胶短纤维、富强纤维均已工业化。普通粘胶纤维由于强度低,尺寸稳定性较差,织物不够理想,富强纤维强度高,尺寸稳定性好,织物比较耐穿,但富强纤维的勾结强度低,断裂伸长较低,纺丝速度慢,     

碱纤维素的研究 第一报 甘蔗渣浆粕的二次浸渍试验

研究了纤维素在碱浸中(一次及二次浸渍)游离碱及结合碱的变化。半纤维素的除去量及纤维细胞的变化,结果表明,对二次浸渍的优异性能应从其碱与纤维素的综合反应考虑。采用草类纤维(甘蔗渣付品浆粕)的原料,用二次浸渍法制备高湿模最粘胶。取得了最佳工艺条件CS_2用量由原工艺44％降至34％KW值由原工艺300以上降至200以下。CS_2降低消耗的百分比与国外近二、三年报导的以木浆进行制备普纤的粘胶相接近。将此法制备的粘胶进行了纺丝试验,纤维的物理机械性质与常法基本一致。     

加热振荡提取-气相色谱-质谱法测定滤棒中两种特征香味成分的含量

建立了加热振荡提取-气相色谱-质谱法（GC-MS）测定滤棒中两种特征香味成分柠檬烯、薄荷醇含量的方法。将滤棒1.0～1.5 g剪成5～10 mm的样品小段,置于100 mL锥形瓶中,加入20 mL无水乙醇和0.1 mL 50 g·L^-1苯甲酸正丙酯（内标）溶液,于30℃加热振荡提取10 min,提取液经0.45μm有机滤膜过滤。采用HP-Innowax毛细管色谱柱（30 m×0.25 mm, 0.25μm）和选择离子监测（SIM）模式,通过GC-MS测定样品中柠檬烯、薄荷醇的含量,内标法定量。结果显示：柠檬烯、薄荷醇标准曲线的线性范围均为0.01～2.00 g·L^-1,检出限（3s）为0.12 mg·L^-1和0.05 mg·L^-1;对同一滤棒样品连续测定5次,柠檬烯和薄荷醇测定值的相对标准偏差（RSD）为2.7%和1.2%;对实际样品进行低、中、高等3个浓度水平的加标回收试验,两种特征香味成分的回收率为91.2%～106%。以凝胶释香滤棒为研究对象,其生产过程中柠檬烯、薄荷醇测定值的批次内RSD（n...     

高卷曲高性能粘胶纤维工艺条件对性能的影响

利用棉绒浆粕和很少量的粘胶变性剂研制成高卷曲高性能粘胶纤维。研究了粘胶和纺丝工艺条件对纤维卷曲性、湿强度、湿模量等性能的影响。调节工艺条件,以高度的纺丝牵伸,得到纤维横截面成不对称的结构,从而获得高度的卷曲和好的性能。试验纤维同美国ITT公司生产的高卷曲高湿模量粘胶纤维比较,其卷曲数、卷曲稳定性、湿强度、湿伸长、湿模量和耐碱性均较高。     

关键制丝工艺对烟气成分中挥发性成分的影响

采用气相色谱-质谱联用仪(GC-MS)测定了不同制丝工艺参数(松散回潮的热风温度、切丝宽度、HT工作蒸汽流量、烘丝热风温度和排潮风门开度)条件下制成的卷烟样品烟气成分中的挥发性成分。结果表明:酯类物质的释放总量在这些工艺参数条件下存在极显著差异的水平,说明酯类物质的释放总量在5种工艺参数不同条件下的变化是极明显的。综合分析部分致香成分和简单酚类的释放总量,选取样品2与样品4的工艺参数条件进行对比可知较高的松散回潮热风温度和烘丝热风温度更加有利于增加卷烟烟气中挥发性成分的释放量;在增加卷烟香吃味方面样品4的工艺参数条件为最佳生产条件,在该工艺条件下生产出的卷烟样品其烟气成分中致香成分的释放总量最多。     

Electron treatment of wood pulp for the viscose process

Electron processing is currently being evaluated by several viscose producers for integration into their process. The viscose industry converts dissolving wood pulp into products such as staple fibre, filament, cord, film, packaging, and non-edible sausage casings. These materials are used in the clothing, drapery, hygiene, automobile, food, and packaging industries. Viscose producers are facing increasingly high production costs and stringent environmental regulations that have forced some plants to close. Electron treatment of wood pulp can significantly reduce the amounts of chemicals used for producing viscose and the production of hazardous pollutants. Acsion Industries has worked with companies worldwide to demonstrate the benefits of using electron treated pulp for producing viscose (rayon). This paper describes the viscose process, the benefits of using electron treatment in the viscose process, and Acsion’s efforts in developing this technology.     

Study of cellulosic fibres morphological features and their modifications using hemicelluloses

The microfibrilar structure and the morphology of the fibre are some of the most important characteristics that determine fibre performance during yarn making. This article is focused on understanding of morphological features of manmade cellulosic fibre and exploring an alternate way to alter fibre morphology. It is observed that though the chemical nature of different types of cellulose fibres viz. viscose, modal and lyocell is same; different processing routes lead to different cross-section and morphologies of fibres which leads to their characteristic properties and spinning behavior. A novel way is attempted to alter the fibre morphology of viscose fibre by changing the fibre regeneration kinetics and molecular weight distribution through addition of low molecular weight and branched structured hemicelluloses in spinning dope. Addition of hemicelluloses in the spinning dope prior to spinning and regeneration of viscose fibres is found to alter the morphology of the fibres without affecting tensile properties of the fibres.     

Pyrolysis products and thermal degradation mechanism of intrinsically flame-retardant calcium alginate fibre

Intrinsically flame-retardant calcium alginate fibre was prepared by wet spinning and its pyrolysis products and thermal degradation mechanism studied. Combustion behaviour and flammability were assessed using the limiting oxygen index (LOI) and cone calorimetry. LOI results showed that calcium alginate fibre was intrinsically flame retardant with LOI value of 48.0, as compared to about 20.0 for viscose fibre. Cone calorimetry indicated that heat release rate and total heat release values of intrinsically flame-retardant fibre were significantly less than those of viscose fibre. It also shown that intrinsically flame-retardant fibre combustion produced greater quantities of residues than did viscose fibre combustion. Combustion residues were examined using scanning electron microscopy, indicating that calcium alginate fibre produced consistent, thick residue crusts. Pyrolysis was investigated using pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) which showed that cracking products produced from calcium alginate fibres combustion were less than those in viscose fibre combustion, and pyrolysis of the intrinsically flame-retardant fibre was incomplete. Thermogravimetric analysis (TG) indicated that calcium alginate fibre generated more residues containing carbonaceous char and calcium carbonate, as compared with viscose fibre. We propose a condensed phase mechanism for the calcium alginate fibre flame-retardancy effect.     

Flame retardant activity of SiO2-coated regenerated cellulose fibres

An alternative route to lower the flammability of viscose fibres is presented. Instead of adding a flame retardant to the viscose dope chemically, we have grown a layer of silica (SiO₂) on the surface of a regenerated cellulose fibre via a sol-gel process. One set of samples was used as-received, while the other was pre-treated in an 18% NaOH solution, giving a rough, etched surface to the fibre. The different surface morphology of both fibre types triggered a different growth of silica layers. On an untreated fibre, silica formed a 300-400 nm thick surface layer containing a high density of cracks and holes. Conversely, on a NaOH pre-treated fibre, the silica layer intruded into fibre interior, adhered more tightly to the fibre structure and formed an almost defect-free, thin (100 nm) layer on the outer fibre surface. This type of silica layer increased the temperature at which the fibre started to decompose by 20 °C. It also hindered significantly the flow of oxygen to the generated volatiles during the thermal decomposition, and increased the temperature of glowing combustion of the residual char; the temperature of the corresponding exothermic peaks increased by ca. 20 °C and 40 °C. In contrast, the thermal effects of silica coatings that grew on an untreated fibre were much smaller.     

Crystallinity changes in lyocell and viscose-type fibres by caustic treatment

One of the most important treatments performed on cellulosic fibres to improve properties such as dimensional stability, tensile strength and lustre, is mercerisation. The aim of this work was to study the crystallinity, accessibility and unit cell structure changes occurring in three types of regenerated cellulose fibres (lyocell, modal and viscose) that were mercerised with caustic soda solutions of different concentrations. Differences were observed between the behaviour of the viscose type fibres (viscose and modal) and that of the lyocell fibres. For the viscose type fibres, the proportion of crystalline regions increased at low alkali concentrations, while for lyocell fibres a decrease in crystallinity was observed. In all three fibres there was a transformation from cellulose II to amorphous cellulose. While for lyocell the transformation was partial, the modal and in particular the viscose fibres showed a complete transformation, and the swelling agent caused the fibre to dissolve at high caustic concentrations.     

Carbonyl Compounds Containing Formaldehyde Produced from the Heated Mouthpiece of Tobacco Sticks for Heated Tobacco Products

Diverse harmful compounds can be emitted during the heating of tobacco sticks for heated tobacco products (HTPs). In this study, the generation of harmful compounds from the filter, instead of tobacco in tobacco sticks, was confirmed. The heat of a heated tobacco product device can be transferred to the tobacco stick filter, resulting in the generation of harmful compounds from the heated filter. Since the heating materials (tobacco consumable) of the tobacco sticks evaluated in this study were different depending on the brand, the harmful compounds emitted from the heated tobacco stick filters were examined by focusing on the carbonyl compounds, using three different tobacco stick parts. Acetaldehyde and propionaldehyde exhibited the highest concentrations in HTP aerosols produced by heating the tobacco consumable (conventional case) (63.5 ± 18.4 µg/stick and 1.71 ± 0.123 µg/stick, respectively). The aerosols produced by heating tobacco stick filters had higher formaldehyde and acrolein concentrations (0.945 ± 0.214 µg/stick and 0.519 ± 0.379 µg/stick) than the aerosols generated from heated tobacco consumable (0.641 ± 0.092 µg/stick and 0.220 ± 0.102 µg/stick). As such, formaldehyde and acrolein were produced by heating small parts of the mouthpiece of a tobacco stick, regardless of the heated tobacco product brand. In addition, acetone was only detected in the aerosols generated from heated filters (0.580 ± 0.305 µg/stick). Thus, safety evaluations of heated tobacco products should include considerations of the harmful compounds generated by heating tobacco stick mouthpieces for heated tobacco products in addition to those found in heated tobacco product aerosols.     

The surface charge of regenerated cellulose fibres

In this paper the influence of charged species on the sheet strength of viscose fibres was investigated. Four samples of chemical modified viscose fibres, as well as a reference fibre were studied. The swelling of these viscose fibres and the breaking length of hand sheets have been determined. Comparing the results, the influence of both, swelling and surface charge on the bonding force, is evident. The allocation of the charges, induced by cationic starch and Carboxmethylcellulose, has been analyzed by Titration, attenuated total reflection spectroscopy (ATR) and X-ray photoelectron spectroscopy (XPS). Titration was used to make a first estimation of the charge distribution within the fibre. Using ATR and XPS, more detailed information about the surface charge has been achieved. All measurement methods showed a significant amount of charge on the fibre surface.     

Influence of water filtration on the determination of a wide range of dissolved contaminants at parts-per-trillion levels

The adsorption of dissolved organic contaminants on glass fibre filters throughout water dissolved/particulate phase decoupling studies was examined. A total of 49 different compounds were considered at low concentration levels (ng L⁻¹), including PAHs, PCBs, organochlorine and organophosphorus pesticides, triazines, thiocarbamates, pyrethroids, phosphate esters and caffeine. Their adsorption on the filters was positively correlated with their log Kow and solubilities, indicating that filter adsorption increased with hydrophobicity. The influence of water properties (i.e. salinity and dissolved organic carbon (DOC) content) was also studied by means of a star experimental design (n = 11). Salinity was the main factor in increasing the adsorption, due to the salting out effect. The influence of DOC suggested that part of the contaminant losses during water filtration may have been caused by the retention on the organic matter adsorbed on the filter surface. Nevertheless, a decrease in filter retention was observed for water with the highest DOC contents, which was probably due to an enhancement of the contaminant solubility in these conditions. Although several factors may control the adsorption process in naturally occurring waters, the extent of the retention of dissolved target analytes on the glass fibre filters should not be underestimated in the analysis of hydrophobic contaminants in marine and estuarine waters at very low concentrations (ppt level).     

Progress in cellulose shaping: 20 years industrial case studies at Fraunhofer IAP

Cellulose, the most abundant renewable organic material on earth, exhibits outstanding properties and useful applications, but also presents a tremendous challenge with regard to economical and environmentally friendly chemical processing. The viscose process, more than 100 year old is still the most widely utilized technology to manufacture regenerated cellulose fibers and films. Viscose fibers are produced today worldwide on a 5 million ton scale with various fiber types ranging from high performance tire yarn to textile filaments and staple fibers with excellent properties close to those of cotton. At Fraunhofer IAP, the technical equipment for viscose preparation, wet spinning of fibers, hollow fibers, and tube-like films is available on a min-plant scale. Research focused on raw materials testing, process optimization with regard to economic and ecological aspects, structural analysis of cellulose during processing, and structure–property relations of fibers and films. Similar to the viscose process, cellulosic fibers can be produced via cellulose carbamate as an environmentally friendly route. In a close cooperation of Fraunhofer IAP with industrial partners, a specific process based on cellulose carbamate was developed on a pilot plant scale, giving fiber properties close to those of conventional viscose fibers. In recent decades the N-methylmorpholine-N-oxide (NMMO)-technology turned out to be a nonderivatizing commercial alternative to the still dominant viscose route. From the very beginning, Fraunhofer IAP has been engaged in investigating the structure formation of cellulose fibers precipitated from NMMO-water solution, revealing structural reasons for the fibrillation tendency of these fibers and means to overcome them. Starting from fiber formation via dry-jet wet spinning, for the first time the blown film formation and the meltblown nonwovens technology were developed for cellulosics on a pilot plant scale at Fraunhofer IAP. Based on the elastic behavior of the dope at elevated temperatures, cellulose can be processed like a melt in the air-gap, offering new possibilities of shaping cellulose like meltable mass polymers. Combining cellulose carbamate with NMMO-monohydrate as a solvent, higher polymer concentrations in the dope and outstanding mechanical properties of the resulting fibers were achieved.     

A comparison of some electronic filters for use in noise suppression circuitry of HPLC detectors

Summary Four electronic filters suitable for baseline noise suppression in HPLC detectors were compared for their response and peak distortion characteristics under conventional HPLC conditions. The filters were designed to be white noise equivalent and the types of filter used were lag, lag-lag, critically damped lag and chain, these being representative of common, simple filter configurations. These filters were evaluated for speed of response to an optical step input signal and also for the effects of their level of noise suppression on peak height, retention time, peak asymmetry and apparent column efficiency. The critically damped lag filter was superior to the other filters in almost all respects and its use considerably enhanced detector performance.