亚硫酸盐对彩色成像过程的影响

研究了彩色显影液中亚硫酸钠对含内偶青成色剂的卤化银单层片的彩色成像过程的各化学反应、青染料影像的有害吸收以及染料云形态的影响,结果表明亚硫酸钠能(1)提高银影像的形成速度;(2)降低成色剂的表观偶合效率;(3)增加青染料影像的有害吸收;(4)使染料云缩小并且使染料云的分布变窄。     

彩色胶片与数字照相的成像效率分析及对其未来的预测

本文作者曾经通过评估成像效率的当前状态和理论极限之间的差距以及分析产生此差距的原因预测过卤化银照相材料的未来发展.本文描述了采用上述的方法来评估和分析彩色胶片与数字照相的现状.经预测在未来前者成像效率的改进余地会远大于后者.     

高氯化银{100}面扁平颗粒乳剂研究进展

高氯化银{100}面扁平颗粒(T-颗粒) 乳剂结合了高氯化银乳剂和T-颗粒乳剂的独到优势,在当代传统照相与数字影像激烈竞争的时期,它的制备与研究有助于提升传统银盐感光材料的竞争力。本文综述了高氯化银{100}面T-颗粒乳剂的制备原料、制备工艺过程、化学增感、光谱增感及该乳剂的应用前景。     

Image Enhancement—Chemical,Digital, Visual

Digital image processing has become well known through the high quality of some spectacular satellite images. It has developed into a discipline in its own right within information science and now finds application, not only in space travel, but also in such diverse fields as, for example, robotics, medical imaging, and television technology. Image processing also occurs, however, in photographic films and biological visual systems. In these systems, too, recorded images are manipulated for better recognition. This poses the question as to whether similar principles of image processing are operative in these different image handling systems.     

Quantification of UV-induced erythema and pigmentation using computer-assisted digital image evaluation

Photography has been used in human skin research for some time. With the advent of digital photography in recent years, its use has increased. However, the focus has now turned from documentation to actual analysis and quantification of skin color changes. The advantages of digital photography outweigh any shortcomings as long as consistent, standardized procedures are followed and quality control is implemented. We present a simple procedure to standardize images and discuss a computer-assisted digital image evaluation (CADIE) technique to quantify skin color changes following UV exposure. The CADIE approach is illustrated with examples from two different studies on UV responses in human skin. Using the Commission Internationale de l'Eclairage L*a*b* color coordinate system in combination with a personal computer and image-editing software, we analyzed digital images obtained in these two studies. We demonstrate the feasibility of using digital photography for objective evaluation of UV erythema in different racial/ethnic groups and for measuring pigmentation changes caused by repeated exposures over a period of several weeks. Our results indicate how objective assessment using CADIE can be an adjunct to visual and optical observation in clinical and scientific evaluations.     

影响重氮片影像颜色的因素

本文探讨了重氮片的主要组份——偶合剂、重氮化合物和成膜剂对重氮片颜色的影响.试验结果说明:不同芳核结构的偶合剂以及在重氮盐中引入不同芳核和取代基对重氮片的影像颜色影响较大,另外,重氮片所用的成膜剂对其影像颜色也有影响.     

彩色照相材料信道容量的研究

本文从信息论观点出发,将彩色照相材料作为一个客观景物信息的传输通道,其单个空间可分辨面积构成一个独立信道,照相材料是大量独立信道并联组成的扩展信道,并提出了使用复层Shannon熵计算彩色照相材料独立信道容量的方法。作者在PDS显微光密度计——电子计算机系统上发展了全套测试计算程序,并完成了中国1821型彩色红外航空负片的信道容量测试。     

X射线衍射仪新功能的开发及其应用

根据Ｘ射线衍射仪的结构特点,通过巧妙而简易的改装,增添了“同步照相”新功能。文中分析了开发新功能的可行性;列举了新功能在某些场合下,能使传统的照相法和现代的衍射仪法结合起来,取长补短的例子;指出新功能有助于提高分析测试水平,并可收到一机多用、节能高效的综合效果。     

金属离子对彩色成像过程的影响

通过测量和计算彩色单层片中成色剂的照相活性、偶合效率以及漂白前银密度等参数,研究了在分散四当量成色剂青(Ⅰ)时掺入金属离子Mg²⁺、Zn²⁺、Fe³⁺和Cu²⁺对彩色青单层片的成像过程中各个化学反应的影响。本实验的结果表明,成色剂中加入的金属离子Cu²⁺和Fe³⁺对成像过程的初始反应中的Ag影像形成产生不利的影响,但它们能促进偶合过程中青(Ⅰ)与显影剂氧化产物作用所生成的隐色体转变成染料的速率。Mg²⁺和Zn²⁺的加入主要是对偶合过程中青(Ⅰ)的偶合效率产生不利的影响。上述原因的综合影响,最终降低了彩色单层片的感光度。     

光栅立体影像的技术进展

人类处于三维世界之中.用我们一双明亮的眼睛能够辨别周围物体所处的相对空间位置,感受这美妙的立体世界.但是,至今广泛采用的照相术,只能记录平面影像,缺乏真实感.立体影像是继平面影像的自然演进.大约30年前,东京大学教授大越孝敬在他1976年的著作《三次元画像工学》里提到"重建空间影像是人类的梦想".其实,这个梦想早已开始,F.E.Ives于1903年已发表利用光栅的立体影像原理.光栅立体影像的应用发展始于1940年,至今已有60多年历史,但一直都未能普及化,一定有其中的原因.     

羟基四氮茚在氯化银乳剂中的超增感作用

我们在前文中^[1]报道了轻基四氮茚化合物(以下简称TAI)对氯化银乳剂感光性能的影响,发现它不仅能提高硫增感氯化银乳剂的感光度,而且也能提高未经硫增感的氯化银乳剂的感光度,同时,还能抑制灰雾的增长.通过对其增感机理的研究表明:TAI增感作用不是发生在显影阶段,而是发生在潜影形成阶段.由于TAI的吸附成盐作用,降低了乳剂的间隙银离子浓度及影响了颗粒表面的空间电荷分布导致了增感作用的发生^[2].     

典型中成药中Cu~(2+)的可视化数值分析法

中药的现代化对中药材及其制剂中重金属的质量控制提出更高要求.本文以Cu2+测定为例,通过测定颜色变化建立了中成药中重金属离子可视化数值分析方法.研究发现,在生理条件下,Cu2+与氨基黑10B可发生氧化还原反应,溶液颜色由蓝色逐渐变为桃红色.通过计算机常规软件Image-Pro Plus6.0获取溶液颜色变化过程中的红绿蓝三原色(R,G,B)数值,发现单位像素内R值的增加与溶液中8.33×10-8～1.33×10-6mol/L范围内的Cu2+具有良好的线性关系.该法可应用于典型中成药补中益气丸、安神胶囊、健胃消食片等药品中Cu2+的检测.     

The importance of questioning scientific assumptions: some lessons from f element chemistry

As scientists, we know that we should constantly question the assumptions upon which our research is based. We also know that we do not do this often enough. The recent results in f element chemistry described here should serve to remind us not to take the traditional boundaries of any area of chemistry for granted including topics as fundamental as redox chemistry and bond-length generalizations. New ways of doing reductive chemistry in the f element area as well as the synthesis of "long bond organometallics" that have unconventional bond distances and reactivity demonstrate how the "rules" in this area, thought to be true for decades, have been recently overturned. The synthetic chemistry that made these advances possible has generated additional unexpected opportunities in f element chemistry that are also described here. Overall, these results should stimulate researchers in all areas to challenge their assumptions.     

荧光读取多层CD光盘(CDLROM)的研制原理

本文研究了在卤化银光敏层的基础上构建多层CD盘的原理,研制了将影像中的银转化为产生荧光产物的方法,从而在应用荧光读取信息时可极大地提高其信噪比.研究后作者得出结论,传统的卤化银照相术能在制造多层光盘CDLROM中得到应用.     

Dihydropyridazine-appended dibenzosuberenones as a new class of fluorophores: Application to fluoride sensing

Highly fluorescent, novel dihydropyridazine-appended dibenzosuberenone type dye molecules were obtained in a single step from simple compounds using Diels-Alder chemistry. This new fluorophore structure can be used for the construction of fluorescent chemosensors, as exemplified by selective and sensitive fluoride ion sensing. The –N–H protons in these structures are acidic enough to allow for fluoride-induced deprotonation, leading to a significant color change as well as a concomitant fluorescence quenching. These fluorophores possess large Stokes shifts, high quantum yields, and long fluorescence lifetimes; therefore, this study potentially paves the way for the construction of novel dye molecules for use in fluorescent dye applications.     

Stability of chromogenic colour prints in polluted indoor environments

Chromogenic colour prints are known to be sensitive to storage environments. However, limited research is available on the effect of atmospheric pollutants on these materials, especially pollutants generated indoors. The stability of photographic dyes is of particular interest and the rate of their change can be best described using the standard RGB colour model. Therefore, the colourimetric method was compared to dye extraction and liquid chromatographic analysis to justify its use as a rapid, non-destructive method for quantitative assessment of the rate of change in dye content of colour photographs during degradation. The effects of typical indoor (acetic acid, formaldehyde) and outdoor (nitrogen dioxide) generated pollutants on chromogenic colour prints were then investigated at 80 °C, 60% RH. It was identified that acetic acid leads to the most pronounced changes in photographic dye concentrations, which is significant considering that acetic acid is often the most prominent pollutant in archival environments. On the other hand, formaldehyde exhibited a slight protective effect in comparison to the blank experiment.     

Anomalous diffusion in an electrolyte saturated paper matrix

Diffusion of colored dye on water saturated paper substrates has been traditionally exploited with great skill by renowned water color artists. The same physics finds more recent practical applications in paper-based diagnostic devices deploying chemicals that react with a bodily fluid yielding colorimetric signals for disease detection. During spontaneous imbibition through the tortuous pathways of a porous electrolyte saturated paper matrix, a dye molecule undergoes diffusion in a complex network of pores. The advancing front forms a strongly correlated interface that propagates diffusively but with an enhanced effective diffusivity. We measure this effective diffusivity and show that it is several orders of magnitude greater than the free solution diffusivity and has a significant dependence on the solution pH and salt concentration in the background electrolyte. We attribute this to electrically mediated interfacial interactions between the ionic species in the liquid dye and spontaneous surface charges developed at porous interfaces, and introduce a simple theory to explain this phenomenon.     

Eco-friendly and protective natural dye from red prickly pear (Opuntia Lasiacantha Pfeiffer) plant

New natural dye extracted from red prickly pear was used for dyeing wool with different types of mordents. The effect of mordant concentration on the color strength was discussed; the results obtained indicated that the color strength decreases with the increase of mordant concentration. The effect of the dye bath pH, salt concentration, dyeing temperature and dyeing time was also studied. The color strength and the dye uptake have exhibited high values. Good fastness properties of the dyed fabric were achieved.Antimicrobial activity of wool fabric dyed with this dye was tested according to diffusion agent. Test organisms as Escherichia coli, Bacillus subitilus, Pseudomons aeruginosa and Staphylococcus aureus were used and the results indicated that the samples exhibited a high inhibition zone.According to the available literature, this is the first report concerning a natural dye for fabric from fruits of red prickly pear plants.