266nm紫外激光反射成像显现潜在指印的研究与应用

为研究现场潜在指印显现、提取的新方法,本文利用紫外激光器输出的波长为266nm的短波紫外激光照射留有潜在指印的检材,以全光谱特种照相取证仪接收记录检材的激光反射图像,并与传统的254nm紫外反射成像技术进行比较。实验结果表明：266nm紫外激光反射成像技术对于显现玻璃、光滑纸张等非渗透性检材表面的潜在指印效果较好;与254nm紫外反射成像技术相比,利用该方法显现的指印具有背景干扰小、反差大的优点。     

短波紫外侧光照明拍摄皱折面上的指印

1　原理在短波紫外反射照相中 ,首先需要考虑客体和指印对光的吸收、反射性质和反射方式。在拍摄提取 50 2、灰尘、粉末类的指印时 ,这些不规则聚集的指印物质在短波紫外区没有明显的吸收 ,表现出较强的漫反射性质。背底随着入射光入射角度的增大 ,其反射光的亮度分布降低。因此 ,在这类指印的拍摄提取时采用侧光照明或掠入射照明技术可以降低背底表面反射光的亮度 ,增加反差 ,更好地提高拍摄提取的效果。在实际工作中 ,短波紫外光源的功率不如可见光大且光源面积较大 ,采用近 90°的角度入射时 ,会使得入射光的强度大为减小 ,在拍摄提取时…     

紫外发光显现技术中时间对显现效果的实验研究

近年来,潜在汗液指印的光学显现技术作为一种无损的显现方法得到越来越多的刑事技术工作者的关注。实验表明,短波紫外发光显现技术对于显现渗透性客体上潜在汗液指印有比较好的显现效果,但是短波紫外发光显现技术对遗留不同时间的潜在汗液指印显现效果差别如何和短波紫外对潜在汗液指印辐射不同时间对指印发光衰减的影响如何,一直没有人研究,针对这种情况,本文就渗透性客体上遗留不同时间的潜在汗液指印的显现和短波紫外辐射不同时间对指印发光衰减展开实验研究。     

游动配光在紫外反射照相中的应用

紫外反射照相在痕迹检验中得到了较为广泛的应用。利用一定的入射角度照射痕 迹客体,使痕迹与客体之间产生一定的紫外反差,从而完成痕迹的拍摄提取。而利用游动配光紫 外反射照相则可以很好地解决在非平面客体上拍摄痕迹的困难。     

利用普通数码相机进行长波紫外摄影的研究

本文根据普通数码相机的感光元件能够感受部分长波紫外线这一特性,使用普通数码相机加上用石英镜头对部分光滑客体及胶带粘面、彩色照片等检材上的汗液指印进行长波紫外线反射拍摄。实验证明了利用普通数码相机进行长波紫外线反射摄影的可行性。     

低温光致可见荧光摄影检验痕迹物证的研究

主要研究了瓷砖、车票、铝合金、光盘、纸张等客体上的矿物油指印、动物油指印、植物油指印、血液指印、红印油指印等微弱痕迹的低温可见荧光摄影的技术方法,通过实验研究获得了拍摄这些痕迹物证的最佳激发光源和吸收滤光镜。     

光滑客体潜在指印的可见光拍摄方法

正在犯罪现场中,案犯的指印遗留在光滑客体上的机会相对较多,如瓷砖、大理石、油漆面、玻璃等。由于光滑客体上的指印反差微弱,拍摄起来比较困难。通过大量的实际操作,现归纳出以下几种可见光拍摄方法,其拍摄效果非常理想。按照物质对光的反射性质不同,可以将物质分为定向反射、漫反射和混合反射三种类型。在光束照射下,三类物质的反射光在方向和强度分布上各不相同:定向反射物质的反射光只出现在反射角方向上,其他方向     

利用全光谱特种照相取证仪进行暗视场照相的研究

为研究光滑客体表面指印的显现、提取方法,本文利用全光谱特种照相取证仪的主光源,以10～30度入射角照射检材,在垂直方向上接收记录检材的反射光亮度分布,显现出亮纹线暗背景的指印图像。因此利用全光谱特种照相取证仪进行暗视场照相可以显现、提取遗留在光滑纸张、油漆、陶瓷等客体表面的潜在指印。     

运用紫外反射照相技术拍摄绒布面上灰尘足迹

运用紫外反射照相技术能有效地加强灰尘足迹与绒布面的反差、减弱或消除绒布底色、纹理的干扰。选择紫外波段的基本原则是确定痕迹物质与客体物质之间呈现最大反差的波段。     

紫外照相对常见痕迹物证的提取

在刑事现场照相工作中，一些常见痕迹物证的无损提取在可见光照条件下往往无法取得令人满意的效果。大量照相实验表明，使用不同波长的紫外线，在一定条件下对某些客体痕迹拍摄提取，可以取得较好效果。     

Managing Money Online

正Internet financial products have enjoyed huge success,but will they change the landscape of China’s financial sector?Wang Kang,27,works for a Beijing branch of the Industrial and Commercial Bank of China(ICBC),a major state-owned commercial bank in China and the largest bank     

International Reactions

正China Chinese State Councilor Yang Jiechi severely criticized Japanese Prime Minister Shinzo Abe’s visit to the Yasukuni Shrine,calling it a brazen affront to people of all countries that suffered from Japanese aggression and colonial rule.     

PEOPLE

正"Reading books gives you access to the knowledge and culture of the people of different countries.The main problem facing China and Turkey in the field of literature is the lack of translated books."Chinese writer and Nobel laureate Mo Yan,calling for more translated literature works at a news briefing in Istanbul on February 22     

NUMBERS

正58 Number of approval items that the State Council canceled or delegated to lowerlevel governments to streamline administration on November 24 $2.3 blnvalue of agreements signed between businesses from Singapore and east China’s Zhejiang Province at the 10th SingaporeZhejiang Economic and Trade Council meeting held in Singapore on November 24 4% Decrease in business revenues in China’s telecom sector in October     

WORLD

正~~     

A White-Hot Battle

正Backing a price war between cab-booking apps serves the larger ambition of China’s Internet companies Han Yonghui is a cabbie in Beijing.After a taxi fare increase in 2013,he makes roughly 5,000 yuan($823)a month,just about enough to feed his family.Recently,Han started using cab-hailing mobile software to pick up customers who order taxis via smartphone.Benefiting from an increasingly fierce competition of rewards between two of the most popular apps for this purpose,he can receive up to 2,250 yuan($370)     

ThePolitical TricksofAbe

正Japan’s leader hopes to salvage his power by way of an early election Japanese Prime Minister Shinzo Abe dissolved the House of Representatives,or the lower house in the country’s bicameral parliament,on November 21.A consequent snap election will be held on December 14,two years ahead of schedule.In recent months,the Japanese economy has continued to slide and entered a technical     

Mid-Term Misfortune

正Barack obama strives for a sound legacy Predictably,the U.S.Republican Party(GOP)took back the Senate after eight years in a landslide victory during the mid-term congressional election in November.While the GOP is still in control of the House of Representatives,it also gained ground in state governor elections in Illinois,Maryland,Iowa and Colorado—the traditional spheres of influence of the Democrats.     

Chinese Machinery Maker Explores overseas Market

正The 15th Russia International Show of Construction Equipment and Technologies(CTT)was held in Moscow from June 3 to 7.Liuzhou OvM Machinery Co.Ltd.attended the exhibition with its prestressed products."At the moment,infrastructure construction such as housing,elec-tric power and railway is continuing to expand in Russia,and given that the country’s import of machinery     

Doing Justice To the Past

正China has declared Japanese Prime Minister Shinzo Abe an unwelcome visitor following his recent visit to the controversial Yasukuni Shrine.When asked whether Chinese leaders would listen to his explanations for the shrine visit in person,a Foreign Ministry spokesman ruled out the possibility by saying that Abe has"shut the door"on dialogue.China is not alone.The U.S.State Department also expressed disappointment at Abe’s visit