Light-induced cracking and abrasion of inkjet prints: Damage and mitigation     

Andrea Venosa  Daniel Burge  Eugene Salesin 《文物保护研究》2016,61(1):94-100

This study is part of a larger research project at the Image Permanence Institute dedicated to digital print preservation issues – the Digital Print Preservation Portal (DP3). Previous DP3 studies determined that certain digital print types are prone to cracking and/or abrasion, and that factors such as low relative humidity, pollutants, and light increase the brittleness of the ink-receiving layer of some inkjet papers. The purpose of this investigation was to explore if light also increases the propensity of inkjet prints to abrade, and to examine the potential of framing glazings to mitigate light-induced physical damage (cracking and abrasion) by attenuating some portion of the UV spectrum. Inkjet papers and prints were subjected to xenon lighting (to simulate daylight through window glass) without glazing, or in sealed framing packages with plain framing glass (soda-lime) or UV filtering glass. Before and after light exposure, brittleness, and abrasion resistance were evaluated independently using two tests: ISO 18907 (Imaging materials – Photographic films and papers – Wedge test for brittleness) and a rub test utilizing a Sutherland® Rub Tester. In this study, exposure to light increased the cracking and/or abrasion tendency of some specimens. The use of UV filtering glass reduced this light-induced propensity in all cases. Plain glass protected all samples from at least one of these two types of surface damage, but was less effective than UV glass. Light-induced brittleness and sensitivity to abrasion were mostly, though not exclusively, caused by UV radiation. It was also seen that some prints may become brittle and/or prone to abrasion in the absence of image fade. Budgeting the amount of light these objects can be exposed to, protecting them from UV radiation, and handling prints with caution especially after exhibition, is essential in order to limit physical damage.  相似文献   

基于线阵CCD的车轮表面缺陷检测系统的图像预处理研究     

吴海滨  夏需堂 《巢湖学院学报》2011,13(3):61-67

介绍了车轮表面缺陷在线检测系统的工作原理和结构组成,对荧光磁粉的激发光谱和发射光谱以及UV(紫外)LED的发光特性进行了分析和研究,重点介绍了缺陷检测系统的数字图像处理和模式识别技术。经过高精度线阵CCD提取的检测图像,通过采用图像增强、平滑去噪、边缘提取以及二值化等方法,可以有效的识别出可疑的缺陷,完成缺陷在线检测系统的识别报警等。  相似文献   

紫外-可见分光光度法测定肉制品中亚硝酸盐   总被引：1，自引：0，他引：1  

梁玉兰 《荆门职业技术学院学报》2010,25(9):5-8

基于酸性条件下,亚硝酸盐与对氨基苯磺酸反应生成有色螯合物,以α-萘胺为显色剂,建立了一种简易快速、易于基层单位使用的有效测定食品中微量亚硝酸盐含量的方法。分别对实验条件的波长、酸度、温度、显色剂用量、显色时间进行优化,取得了最优的实验条件参数,对食品中香肠、腊肉和肉脯样品里的亚硝酸盐含量进行加标回收测定检验,回收率可达98%以上。  相似文献   

紫外诱变酿酒酵母筛选耐高温菌株     

李艾  李云凯  程磊 《唐山学院学报》2013,26(3):35-37

以实验室保存的酿酒酵母为初始菌株,采用紫外分光光度法测定菌株浓度,绘制出菌株生长曲线,由此确定出最佳诱变菌龄为3～10h,在此期间利用紫外线对菌株进行诱变,筛选出一株适于在高温下发酵的菌株,紫外线诱变条件为：紫外灯功率10w,照射距离30cm,照射时间3min。此菌株在37℃下培养72h,其成熟发酵醪酒精产率为3．837％。  相似文献   

紫外分光光度法测定诺氟沙星的含量     

陈红  郑典慧 《台州学院学报》2004,26(3):64-65

用紫外分光光度法测定诺氟沙星的含量，选用0．1mol／L氢氧化钠为溶剂，在272．5nm波长处测定吸光度，诺氟沙星的线性范围为0-10μg／ml，相关系数r=0．9998。相对标准偏差为0．65％(n=6)。应用拟定的方法测定药物制剂中诺氟沙星的含量与文献方法一致。  相似文献   

紫外线诱变庆大霉素产生菌育种与发酵条件的研究     

龙石红  邓斌 《湘南学院学报》2002,23(5):120-122

以紫外线为诱变剂,用庆大霉素产生菌JY1-12为出发菌株,选育出性能优良的菌株JY3-5.经正交试验确定其最佳发酵培养基,研究了最佳发酵温度和初始pH值,使其摇瓶效价提高35.1%;30m3灌放大试验,比出发菌株效价提高19.2%.  相似文献   

题目：遗传改造细菌基因组的策略：基因定点突变、基因失活和基因过表达     

Jian-zhong Xu  Wei-guo Zhang 《Journal of Zhejiang University. Science. B》2016,17(2):83-99

With the availability of the whole genome sequence of Escherichia coli or Corynebacterium glutamicum, strategies for directed DNA manipulation have developed rapidly. DNA manipulation plays an important role in understanding the function of genes and in constructing novel engineering bacteria according to requirement. DNA manipulation involves modifying the autologous genes and expressing the heterogenous genes. Two alternative approaches, using electroporation linear DNA or recombinant suicide plasmid, allow a wide variety of DNA manipulation. However, the over-expression of the desired gene is generally executed via plasmid-mediation. The current review summarizes the common strategies used for genetically modifying E. coli and C. glutamicum genomes, and discusses the technical problem of multi-layered DNA manipulation. Strategies for gene over-expression via integrating into genome are proposed. This review is intended to be an accessible introduction to DNA manipulation within the bacterial genome for novices and a source of the latest experimental information for experienced investigators.  相似文献   

UV覆盖优化标准的初步研究     

张仙玲  裴晓芳  陶纯堪 《南京晓庄学院学报》2006,22(4):27-30

UV覆盖是光学综合孔径成像技术中一个关键环节,它决定于孔径阵列的排列情况,且影响到后续的图像恢复工作,所以,必须对UV覆盖进行优化,但优化标准目前尚未确定.本文利用统计的方法从研究图像频谱的高低频特性入手,从对不同方式下UV覆盖对后续的图像恢复造成的影响情况的分析比较,进行优化标准的初步研究与探讨.  相似文献   

原生质体紫外诱变选育茶薪菇的研究   总被引：2，自引：0，他引：2  

张渊 王谦张筱梅  张焕英张焕英 《保定师专学报》2003,16(4):24-26

研究了茶薪菇原生质体的形成及影响因素，并进行了以原生质体为材料的诱变育种工作．实验表明，培养5天的茶薪菇茵丝体酶解3小时原生质体数目达到最大值．原生质体经紫外线照射20秒，致死率即达70％以上．再生茵株经筛选后，原生质体再生株C16和诱变株C304产量较对照分别提高了42．7％和17．9％．  相似文献   

Use of Computer Modeling of Site-Directed Mutagenesis of a Selected Enzyme: A Class Activity for an Introductory Biochemistry Course     

Jones  Marjorie A.  Shoffner  Raymond  Friesen  Jon 《Journal of Science Education and Technology》2003,12(4):413-419

For an introductory undergraduate biochemistry class, we developed an interactive, out of classroom, team project that would allow students to gain a better understanding of protein structure and function. This project involved the use of the molecular visualization program RasMol and computer simulated site-directed mutagenesis of selected amino acids of the enzyme, Uroporphyrinogen decarboxylase. Survey data from students after completion of the project indicated that they had developed a more complete understanding of protein three-dimensional structure leading to functionality.  相似文献