几种异纤清除机检出效果试验及选型体会

探讨不同异纤清除机的检出效果。介绍了几种国内外异纤清除机的应用情况。就棉纺企业如何选择异纤清除机的问题进行了讨论,并对两种异纤清除机的清除效果进行了对比试验。试验结果表明,精灵-8型异纤清除机的标准试纸投放检出率达到90%,实际异纤投放检出率达到92.6%,经该机清除异纤后织布,布面检验异纤数量较少。认为:精灵-8型异纤清除机清除效率相对较高,且运转性能较为稳定,是使用性能较为成熟的异纤清除设备。     

异纤的危害及清除方法探讨(续完)

探讨异纤的危害及清除方法.阐述了异纤的危害以及纺织工程中清除异纤的方法与途径,重点介绍了开清棉流程中异纤清除装置的原理及应用示例.认为:目前国内异纤清除装置的检测技术已逐渐趋于成熟,基本能够满足对异纤纱疵的控制要求.指出:解决异纤问题必须从源头抓起;在开清棉流程中安装异纤清除装置是取代人工挑拣异纤的一种较理想的方法,但对于漂白织物或高档织物用纱,需要将其与络筒机上带有异纤清除功能的清纱器相结合使用;纺纱企业不能盲目追求无人化,需要综合考虑各种因素来确定异纤清除设备的投入;不同识别技术对各种异纤的检出各有优势与不足,需要纺机企业加强多种检测技术相结合的研究,开发出体现优势互补的异纤清除装置或设备.     

异纤的危害及清除方法探讨(待续)

探讨异纤的危害及清除方法。阐述了异纤的危害以及纺织工程中清除异纤的方法与途径,重点介绍了开清棉流程中异纤清除装置的原理及应用示例。认为:目前国内异纤清除装置的检测技术已逐渐趋于成熟,基本能够满足对异纤纱疵的控制要求。指出:解决异纤问题必须从源头抓起;在开清棉流程中安装异纤清除装置是取代人工挑拣异纤的一种较理想的方法,但对于漂白织物或高档织物用纱,需要将其与络筒机上带有异纤清除功能的清纱器相结合使用;纺纱企业不能盲目追求无人化,需要综合考虑各种因素来确定异纤清除设备的投入;不同识别技术对各种异纤的检出各有优势与不足,需要纺机企业加强多种检测技术相结合的研究,开发出体现优势互补的异纤清除装置或设备。     

异麦芽低聚糖的酶法制备

研究了异麦芽低聚糖的酶法制备：以α－葡萄糖苷酶作用于２０％麦芽糖溶液,生成含２５．２％异麦芽糖和２４．０％潘糖的异麦芽低聚糖。异麦芽糖含量等主要指标明显优于国外的同类产品。     

高效液相色谱法测定异麦芽糖浆组分

异麦糖浆是一种含异麦芽糖,潘糖,异麦芽三糖以及分枝四糖,分枝五糖以上的其它分枝低聚糖组成的淀粉糖浆。分枝低聚糖含量占总糖份的５５％以上。采用高效液相色谱法,以Ａｍｉｄｅ－８０色谱柱和Ｗａｔｅｒｓ４１０示差折光检测器对异麦糖浆中各组分进行快速地分离测定。     

酶法合成异V_C混合脂肪酸酯及其抗氧化性能

在Lipozyme 435脂肪酶催化下,利用异VC与山茶油、猪油、麻油和菜籽油分别发生酯交换反应,合成异VC混合脂肪酸酯,产物用柱层析法分离纯化。以山茶油与异VC反应为例,详细考察了反应溶剂、反应时间、反应物配比、酶用量和油脂回收循环使用对反应转化率的影响。优化条件下,反应转化率最高达到48%。将合成的异VC山茶油脂肪酸酯、异VC猪油脂肪酸酯、异VC芝麻油脂肪酸酯和异VC菜籽油脂肪酸酯应用于新鲜山茶油中,用过氧化值法(POV)进行抗氧化试验。结果表明,异VC混合脂肪酸酯是良好的脂溶性抗氧化剂,并表现出明显的剂效关系。     

异纤异收缩纤维的开发

主要介绍用FK6-900加弹机生产异纤异收缩纤维的设备改造，工艺流程，工艺参数及质量控制。     

对甲苯磺酸催化合成季戊四醇异硬脂酸酯工艺优化及其表征分析

为改善现有季戊四醇异硬脂酸酯生产工艺存在的反应时间长、反应温度高、效率低等问题,研究采用对甲苯磺酸催化季戊四醇与异硬脂酸酯化合成季戊四醇异硬脂酸酯。以异硬脂酸酯化率为考察指标,利用单因素实验和正交实验对酯化工艺条件进行优化,对酯化粗产物进行除酸提纯处理,并对粗产物进行红外光谱分析,对除酸提纯产物进行质谱分析、热重分析及性能指标测定。结果表明：最优的酯化反应工艺条件为反应时间5 h、反应温度140℃、催化剂用量1%(基于反应总投料质量)、异硬脂酸与季戊四醇物质的量比值4.3,在此条件下酯化率为99.27%,粗产物酸值(KOH)为13.26 mg/g。红外光谱结果表明此酯化反应合成了季戊四醇异硬脂酸酯,质谱鉴定结果显示主要合成产物为季戊四醇四异硬脂酸酯。经脱酸处理,产物的酸值(KOH)降为3.23 mg/g,与市售产品接近,热重分析及性能指标测定结果显示提纯产物具有优异的热稳定性,良好的黏温性能、优异的低温流动性及良好的安全性。优化的对甲苯磺酸催化合成季戊四醇异硬脂酸酯工艺具有能耗低、产物品质高的优点。     

数码紫外荧光成像技术与原棉异纤检测

以有色异纤和无色异纤为研究对象,提出了针对这两类异纤的有色异纤检测模块和无色异纤检测模块,着重介绍了基于紫外荧光效应的无色异纤检测模块.     

低聚异麦芽糖产品中主要组分的毛细管电泳分析方法

在未涂渍的石英毛细管中 ,以 75mmol/L硼砂 (pH 1 0 5 )为运行电解质 ,在检测波长 2 1 4nm、分离电压 1 5kV下对低聚异麦芽糖的主要组分的α 萘胺衍生物进行了快速分离测定。结果表明 ,该方法重现性好 ,迁移时间和峰面积的相对标准偏差分别在 0 5 %和 2 0 %以内。异麦芽糖、异麦芽三糖、潘糖浓度在 0 0 0 5～ 1 0 0 0mg/mL范围内 ,含量均与其峰面积之间呈现良好的线性关系。该法灵敏度高 ,成本低 ,为测定低聚异麦芽糖产品中主要组分提供了一种高效快速的方法     

Original semiologic standardized evaluation of stratum corneum hydration by Diagnoskin stripping sample

In a normal and healthy skin, the regular elimination of the superficial corneocytes, called desquamation, is a fundamental physiologic process intended to protect the barrier function of the skin. This invisible loss of corneocytes, individually or in small groups, is incessantly compensated by the divisions of the proliferative layer and the upward cellular maturation in order to maintain the harmonious renewal of the epidermis and the integrity of the stratum corneum. The harmony of this desquamation process is intimately conditioned by a sufficient hydration of the stratum corneum: (i) an abnormal desquamation leads to a disruption of the water barrier function and consequently to a dehydration tendency of the stratum corneum, and (ii) a cutaneous dryness (whatever the cause) is able to disturb the desquamation process. Protecting the water content of the stratum corneum has always been a major preoccupation of the cosmetic industry scientists. Consequently, the moisturizing properties of a cosmetic product are objectively measured by various explorations directly targeted on the hydration (corneometry) and on the level of the water barrier function (transepidermal water loss (TEWL) measurements), which depends directly on the skin hydration state. This intimate linkage of the desquamation process and the water content of the stratum corneum enable us to suggest an indirect assessment of the hydration from a direct study of the desquamation by examining a skin-stripping sample (D-Squames) by an optical microscope (linked to a computer). We will describe this already known technique and mainly its new and unpublished semiologic exploitation, named Diagnoskin, whose advantages are its simplicity and its reproducibility particularly interesting in the case of sequential appraisal of dermatologic or cosmetic treatments.     

纺纱牵伸胶辊胶圈应用技术概要

阐述棉纺牵伸胶辊、胶圈的应用技术和牵伸原理,重点探讨了胶辊、胶圈的牵伸工艺特性及其合理配置、胶辊制作、周期管理、质量管理、使用管理、产品缺陷与其机械波分析、纺纱环境和挡车工操作水平对纺纱性能的影响,提出胶辊、胶圈有关机件的质量要求等。     

Non-destructive analysis of anthocyanins in cherries by means of Lambert-Beer and multivariate regression based on spectroscopy and scatter correction using time-resolved analysis

In high-value sweet cherry (Prunus avium), the red coloration - determined by the anthocyanins content - is correlated with the fruit ripeness stage and market value. Non-destructive spectroscopy has been introduced in practice and may be utilized as a tool to assess the fruit pigments in the supply chain processes. From the fruit spectrum in the visible (Vis) wavelength range, the pigment contents are analyzed separately at their specific absorbance wavelengths.A drawback of the method is the need for re-calibration due to varying optical properties of the fruit tissue. In order to correct for the scattering differences, most often the spectral intensity in the visible spectrum is normalized by wavelengths in the near infrared (NIR) range, or pre-processing methods are applied in multivariate calibrations.In the present study, the influence of the fruit scattering properties on the Vis/NIR fruit spectrum were corrected by the effective pathlength in the fruit tissue obtained from time-resolved readings of the distribution of time-of-flight (DTOF). Pigment analysis was carried out according to Lambert-Beer law, considering fruit spectral intensities, effective pathlength, and refractive index. Results were compared to commonly applied linear color and multivariate partial least squares (PLS) regression analysis. The approaches were validated on fruits at different ripeness stages, providing variation in the scattering coefficient and refractive index exceeding the calibration sample set.In the validation, the measuring uncertainty of non-destructively analyzing fruits with Vis/NIR spectra by means of PLS or Lambert-Beer in comparison with combined application of Vis/NIR spectroscopy and DTOF measurements showed a dramatic bias reduction as well as enhanced coefficients of determination when using both, the spectral intensities and apparent information on the scattering influence by means of DTOF readings. Corrections for the refractive index did not render improved results.     

Chlorophylls,carotenoids and anthocyanin concentrations in the skin of ‘Gala’ apples during maturation and the influence of foliar applications of nitrogen and magnesium

‘Gala’ apple fruit were sampled over two growing seasons, to determine the effects of maturation, and of foliar applications of nitrogen and magnesium on pigment concentrations and colour development in maturing fruit. Treatments of urea and/or magnesium sulphate sprays were applied to the trees in a commercial orchard. The chlorophyll, carotenoid and anthocyanin concentrations in the fruit skin were determined for both the blush and back sides over 15 harvests in 1991–1992. In 1990–1991, the skin chlorophyll concentrations were determined only for the back side of the fruit. The fruit nitrogen, magnesium and sulphur concentrations were determined near maturity. The concentrations of chlorophyll and carotenoids in apple skin decreased from the first harvest in 1991–1992 as the fresh weight increased from 12 g, 40 days from flowering to 140 g, 138 days from flowering. Chlorophyll continued to decrease whereas carotenoid concentrations increased after 138 days and until at least 153 days. The average skin chlorophyll and carotenoid concentrations were higher on the blush side of the fruit than on the back. The total chlorophyll per fruit increased from the first harvest to a peak about 70 days after flowering in 1990–1991 and then decreased over the remainder of the period studied. The time of this peak was about 40 days later in the 1991–1992 season compared with the 1990–1991 season. The total carotenoid increased up to about 50 days after flowering in 1991–1992, fluctuated and then decreased up to 138 days when the amount increased again. The ratio of carotenoids to chlorophylls was highest for the first three harvests, fluctuated somewhat up to c 138 days after flowering after which the ratio increased rapidly. The anthocyanin concentrations were low and fluctuated up to 130 days from flowering and then increased markedly only on the blush side at 130 days, about 14 days before the carotenoids started to increase. The treatment of the tree canopy with urea increased the chlorophyll and carotenoid concentrations in the fruit skin, 14–20 days after the first application until after maturity, more so on the blush side than on the back side. These increased concentrations were maintained up to the harvest after which carotenoid concentrations increased. The urea treatment lessened the increase of anthocyanin concentrations in the blush side skin of the fruit, at maturity. At maturity, the nitrogen concentration of fruit from urea treated trees was higher than those from untreated trees. The magnesium sulphate treatment of the canopy increased the chlorophyll and carotenoid concentration on the back of the fruit within 20–30 days from commencing spraying. The ‘ground colour’ scores for the back sides of the fruit (used for fruit picking and grading) were greener for the urea treated fruit and reached an acceptable score about two weeks later than the untreated fruit. ©1998 SCI     

高校宝石及材料工艺学专业的构建研究

通过回顾高校宝石及材料工艺学专业的创建历程,深入探讨了该专业未来发展所面临的、深层次的理论问题,即学科属性与文化背景,学科构成与知识内涵,学科方向与实践定位,学科任务与社会功能。在此基础上,建立了多层次技术教育的社会功能模型,由此推断：高校中的宝石及材料工艺学专业属于多层次技术教育中的高等职业技术教育。同时,还构建了该专业的技术教育的社会功能模型和学科构成模型,进一步确立了该专业的社会实践定位。     

Measurement of paralytic shellfish toxins in molluscan extracts: comparison of the microtitre plate saxiphilin and sodium channel radioreceptor assays with mouse bioassay, HPLC analysis and a commercially available cell culture assay

This study compared five methods of measuring paralytic shellfish toxins (PSTs) including the long-used mouse lethality bioassay, a commercially available cell culture test (MIST ® Quantification kit), HPLC analysis, and two newly developed radioreceptor assays utilizing mammalian sodium channels and saxiphilin. Methods were challenged with toxic shellfish extracts prepared according to the AOAC official method. The best correlations between predicted toxicity values being 0.9 or better, were those between HPLC analysis when compared with both radioreceptor assays and the mouse lethality bioassay, as well as that between the saxiphilin and the sodium channel radioreceptor assays. In all cases, statistically significant correlations existed between the toxicity measurements of the same extracts. The ratios between some methods were not unitary as measured by the slopes of the regression lines used for correlation analyses. HPLC analysis predicted more toxicity than all of the bioassays. The saxiphilin assay underestimated toxicity relative to the mouse bioassay, the MIST ® kit determinations and the sodium channel assay. The sodium channel assay predicted there to be less toxicity than the mouse bioassay and the MIST ® kit. Of all of the techniques used, the MIST ® kit correlation with the mouse bioassay was nearest to one. Each method possesses different virtues and it may be that a multi-method approach would harness the benefits of each method for various aspects of a shellfish testing regime.     

Prediction of worst case migration: presentation of a rigorous methodology

An improvement of the Piringer model, allowing the prediction of a worst case migration from packaging to food is presented here. The authors are proposing other constants for the calculation of the upperbound value of the diffusion coefficient, using experimental data determined by a film to film method. Considering the plasticizing effects of food simulants, a model involving the variation of the diffusion coefficient versus space and time must be used. Future fields of investigation are discussed: the relationship between diffusion coefficients and the volume of the migrant (instead of molar mass), and the variation of diffusion coefficient activation energy with temperature.     

赛络纺纱钢领、钢丝圈的选配实践

为了提高赛络纺纱成纱质量,减少细纱断头,从钢领、钢丝圈的种类,卷绕过程中对纺纱的影响及其运动配合等诸多因素出发,论述了钢领、钢丝圈的选配原则,重点阐述了赛络纺纱钢丝圈运动形态的变化及钢领、钢丝圈的选配要求,通过纯棉、非棉纤维纺纱的选配实践,指出赛络纺纱线毛羽少,结构紧密,应根据纺纱纤维性能和纺纱特点,以纱线通道通畅降毛羽、运行平稳少断头、散热良好延长使用寿命为原则对钢领、钢丝圈进行选配。     

合理优化并条工艺 减少针织纱细节

为了减少并条工序对成纱细节的影响,分析了并条机的工艺参数设置和工艺配置原则以及运转管理对棉纱细节的影响,针对影响棉纱细节的因素提出优化工艺配置、完善生产管理时应注意合理选择罗拉隔距及前后区牵伸分配、喇叭口直径,压力棒调节环直径以及胶辊直径,同时在生产管理中应减少意外牵伸、加强巡回检查和操作管理工作,从而保证棉条更加均匀、棉纱细节大幅降低。