银影分散法增强照相影像

银影分散法增强照相影像是基于通过氧化还原反应 ,使再次形成的银影像颗粒缩小到原颗粒的约 1/100,提高银遮盖力从而增强照相影像。明胶层中来自卤化银晶格的银离子 Ag＋ 在非催化还原过程中的络合作用决定银颗粒缩小程度,因而也是决定银遮盖力的关键因素。银离子的络合作用受乳剂层结构和经常规方法显影后生成的影像银氧化还原条件的影响。 本方法突出的特点是通用性和高效性 ,各种用途的黑白卤化银感光材料 ,包括工业和医用胶片,它们对电离辐射感光度可以提高 6～ 8倍 ,并保持影像原有的细部的分辨能力。     

喷墨打印接受材料的研制

喷墨打印的应用正得到迅速发展 ,其主要原因是喷墨打印的质量特性 (包括清晰度、色彩还原、耐光性及耐水性等 )有了明显改进。能获得照相质量彩色影像的喷墨打印 ,已使其进入了应用于高质量招贴画的工业化领域。这些图像高密度的取得借助于专门的三维密度墨汁。喷墨打印质量的改进 ,不仅与新型号高清晰打印机的开发有关 ,而且也和新的专用耗材的开发相关。是否能应用喷墨打印得到照相质量的影像 ,这对数字照相的发展极为重要。为此 ,喷墨打印接受材料 (纸或胶片 )应保证最大的清晰度、出色的色彩还原 ,并且没有影像的“易污性”。这就要通过…     

数码红外照相技术在刑事照相中的应用

红外数码照相技术是利用CCD或CMOS感光元器件记录物体反射、透射或发射红外线影像的过程.与使用红外胶片的常规红外照相相比,数码红外照相具有操作方便快捷,适用范围广,成像效果好,后期制作简便,即拍即显适时观察效果,便于普及应用等优点.     

1999年爱克发公司的市场经营状况

爱克发公司是世界上主要的感光照相和影像产品的生产厂家之一。经过130多年的发展,爱克发公司已经成为一家著名的跨国公司,主要产品有各类银盐照相和数字成像设备、材料和服务,如印刷制版胶片、医用和工业用射线胶片、专业摄影和业余摄影用途的照相设备、彩色和黑白胶片／相纸以及各类数字成像照相机、设备和服务。 对爱克发公司来说,1999年是卓有成效的一年。1999年初,爱克发公司实行了公司重组,正式在布鲁塞尔股票交易所和法兰克福股票交易所挂牌交易;同年5月,又收购了美国Sterling医疗诊断成像公司,成为世界上医用胶片和PACS系统的最大生产厂家。由于爱克发公司采取各种积极有效的市场营销策略和世界影像市场的快速发展,爱克发公司1999年的经营状况明显好于1998年,实现销售收入47．31亿欧元,比1998年的43．62亿欧元增长8．5％。表1为爱克发公司1998年和1999年的经营指标比较。     

灰雾较大的X射线胶片在加厚时的质量控制

X射线胶片由于曝光或显影不当,容易造成灰雾较大、密度和反差过小,直接影响X射线胶片的影像质量和临床诊断.经实践证明,采用对此种质量X射线胶片进行加厚补救,可获得较理想的影像效果.     

Digital Now公司发布干胶片加工技术

2000年9月25日,数字成像公司Digital Now发布了一种不使用液体化合物对胶片底片进行显影,而是通过扫描来制作影像的数字拷贝照相加工技术.     

显影加工控制方法对印刷胶片质量影响

印刷胶片的影像特性对印刷品质量的影响极其显著,胶片冲洗过程中的操作控制是CTF的核心技术和关键环节。本文采用正交试验方法,探讨了胶片冲洗过程的控制要素——显影液稀释比、显影温度、时间,定影液稀释比、定影温度、时间,显影液和定影液疲劳程度等,并对这些要素的影响进行了排序。最后,通过显影动力学试验,确定了"华光"牌印刷胶片冲洗的最佳控制条件,对提升胶片冲洗加工质量有一定的指导意义。     

照相感光材料用卤化银

卤化银是制造照相感光材料中不可缺少的化学品,由于照相胶片的不断翻新,世界各国对卤化银的需要就增长起来。目前国际上使用的胶片有黑白胶片、彩色胶片、彩色反转正片等几类,而其中彩色胶片中一次成像彩色胶片最为新颖。现列最近1978～1982五年内各国对彩色胶片的消费量于下:     

照相知识杂谈(六)染料有害吸收和马斯克

当1935年彩色反转胶片柯达克罗姆问世之时,它鲜艳的色彩,准确的还原宣示了减色法多层彩色胶片主导彩色照相时代的到来.可其后,当好莱坞因为发行电影,需要多部拷贝片,必须从拍摄原件再复制拷贝,或经过中间工作片来复制拷贝时,不管是反转复制,还是负正复制拷贝,其色彩还原质量都大打折扣,严重失真.这种现象人们起初还莫明其妙,后来才明白,这是因为染料存在有害吸收等性能缺陷所致,并由此创造性地发明了马斯克技术,应用后大大地改善了彩色摹演影像的色彩还原质量.     

关于改进照相明胶质量的探讨

<正> 照相明胶是制造胶片的主要原材料之一,它的质量优劣对胶片的质量有重要影响。近几年来,由于各制胶厂引进了国外部分关键设备,如板式蒸发、长网干燥、无菌包裝等,大大改善了明胶后期生产的工艺条     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

基于ATRP法制备的触角状亲水性羟胺树脂的吸硼性能的研究

以大分子引发剂氯乙酰化聚苯乙烯微球(PS-acyl-Cl)经原子转移自由基聚合(ATRP)法引发丙烯酰胺(AM)和甲基丙烯酸缩水甘油酯(GMA)单体的共聚接枝,制得一种触角状亲水性环氧载体(PS-acyl-g-P(AM-co-GMA)),再经二乙醇胺(DEA)的环氧基开环胺化反应,得到一种含多个-NCH2CH2OH螯合配基的多齿-五元螯合环的触角状亲水性羟胺树脂(PS-acyl-g-P(AM-co-GMA)-DEA)。将此树脂用于硼吸附研究,结果表明,PS-acyl-g-P(AM-co-GMA)-DEA树脂对硼的吸附满足Langmuir方程,为单分子层吸附;饱和吸附量约为37.7 mg·g-1,且树脂5 min即可达到吸附平衡,与其它已报道的吸硼树脂相比,该树脂具有更高的吸附量和吸硼速率。吸附动力学研究表明,树脂吸附硼的过程主要由颗粒扩散过程控制。重复使用5次后该树脂的吸附量基本不变,解吸率均在90%以上,重复使用性能良好。