Dependence of the Constant of the Mark‐Houwink Equation under Theta Conditions on the Bulk of Substituents for Hydrocarbon Polymers

The logarithm of the constant K _θ in the Mark‐Houwink equation under theta conditions was found to be proportional to the molar volume of the substituent groups in the case of vinyl‐ and vinylidene‐type hydrocarbon polymers. This simple empirical relation can be used to estimate K _θ for such polymers.     

用于BNCT-SPECT的帕维亚TRIGA MARK II反应堆热柱优化设计

针对坐落于意大利帕维亚大学的TRIGA Mark II反应堆热柱结构进行优化设计,从而满足面向硼中子俘获治疗(BNCT)的单光子发射计算机断层成像(SPECT)研究要求。为提高计算效率并减小统计误差,对比分析使用SSW/SSR方法与直接使用反应堆为源项时热柱内照射位置处中子能谱,其结果基本一致,从而验证了SSW/SSR方法的可靠性。为在该反应堆开展BNCT中SPECT实验,热柱中子束需准直为笔形束。对比分析四种热柱优化方案下束流口处及探测器处热中子和光子通量：40 cm长石墨(射束口5 cm3 cm);0.5 cm厚硼包裹40 cm长石墨(射束口5 cm3 cm);30 cm长天然锂聚乙烯(射束口直径4 cm);30 cm长天然锂聚乙烯(20 cm长射束口直径5 cm,5 cm长射束口直径4 cm,5 cm长射束口直径2 cm)。结果显示,射束口处热中子通量分别为1.05108,2.52107,6.08107和5.10 107 #/(cm2s)。综合考虑中子准直效果及光子污染,方案三具有最优性能。为后续进行BNCT-SPECT理论和实验研究提供了基础,从而有效促进BNCT剂量准确评估方法的研究进程。     

Interpolation algorithm for recovering the missing phase values in 3D measurement

In the three-dimensional (3D) phase measurement, some marks are usually adhered to the object in order to make the 3D registration process faster and easier. As covered with marks, local phase data are missing and have to be interpolated later. Considering the phase distribution nearby the marks, a gradient estimate (GE) interpolation algorithm is provided here. This algorithm recovers one pixel's missing phase value with the average of the estimated values which is calculated by gradients in eight directions nearby. Since this algorithm is a local processing, the missing phase values should be interpolated from the edge of the marks to the center. In the computer simulation and the practical experiment, compared with the same-size neighborhood mean (NM) algorithm and the Gerchberg-Saxton (GS) algorithm, this new algorithm achieves very good fit results with the least time. So it can be used as a practical tool for automatic missing phase interpolation.     

The use of Raman microscopy and laser desorption ionization mass spectrometry in the examination of synthetic organic pigments in modern works of art

Synthetic organic pigments are widely used in modern and contemporary works of art. They have been examined by a variety of techniques including spectroscopic methods such as Fourier transform infrared spectroscopy, Raman, and X‐ray powder diffraction as well as chromatographic or mass spectrometric techniques such as pyrolysis‐gas chromatography/mass spectrometry and laser desorption ionization mass spectrometry (LDI–MS). Often, a combination of techniques has been used to examine these pigments. This paper describes use of Raman spectroscopy to create a database of colorants including two pigments not previously reported, PO1 and PO2. Then, using Raman spectroscopy in combination with LDI–MS, samples from modern works of art by artists including Mark Rothko, Barnett Newman, and José de Rivera were examined in order to identify the pigments present. One finding was that Rothko used a variety of red pigments over the course of his career including PR11 which has not been previously reported in artwork, and PO2 found with its positional isomer PR1. Knowledge of the colorants serves to inform conservators about display and treatment decisions. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.     

The Paternity of the H-Bombs: Soviet-American Perspectives

There are major problems in the history of the American and Soviet hydrogen bombs. They are associated with the Teller-Ulam and Teller-Oppenheimer controversies, and the question of whether the design of the Soviet H-bomb was an independent conception. Because of the scarcity of documentary evidence, these problems have little chance of being settled if the histories of the two are considered separately within their national frameworks. Considered comparatively, however, they can help clarify these problems separately and convert them into different facets of this most important segment in the history of the thermonuclear age.The recently disclosed evidence on the history of the Soviet H-bomb, in particular, on Klaus Fuchs’s key idea of radiation implosion, validates Edward Teller’s view on the invention of the H-bomb, including his understatement of his own accomplishment and his concern about the benefits and head start that the Soviet H-bomb program could have gotten from Fuchs’s espionage. In addition, the Russian perspective on the realities of illusory worlds during the Cold War helps us see these illusory worldviews as largely responsible for the intensity of the H-bomb debate in the United States. Gennady Gorelik is a research fellow in the Center for Philosophy and History of Science at Boston University and is the author of biographies of Matvei Bronstein and Andrei Sakharov.     

A novel method for detecting and counting overlapping tracks in SSNTD by image processing techniques

Overlapping object detection and counting is a challenge in image processing. A new method for detecting and counting overlapping circles is presented in this paper. This method is based on pattern recognition and feature extraction using “neighborhood values“ in an object image by implementation of image processing techniques. The junction points are detected by assignment of a value for each pixel in an image. As is shown, the neighborhood values for junction points are larger than the values for other points. This distinction of neighborhood values is the main feature which can be utilized to identify the junction points and to count the overlapping tracks. This method can be used for recognizing and counting charged particle tracks, blood cells and also cancer cells. The method is called “Track Counting based on Neighborhood Values” and is symbolized by “TCNV”.     

对机读卡民文信息采集系统的探讨

针对当前新疆维吾尔自治区招生考务管理工作中急待解决的一个问题，即万卡通数据录入系统（ＧＤＲＳ）只能识别英文，汉文而无法识别民文的问题，设计出在无民文ＤＯＳ系统的支持下也可以采集民文信息的新方案，本项目１９９６年在自治区教委立项并研制成功，填补了新疆计算机考务管理工作的空白，在１９９７年的普通高校招生统一考试，录取工作中推广实用，效果很理想。     

看谱分析技术在铁基材料锰、钼等元素测定中的应用研究

对看谱分析技术中的强度标法进行了应用研究,摄制了相应的彩色图谱,研究了分析线和比较线的选取及使用等关键技术.研究结果能够满足合金材料元素定性和半定量分析的需要,实现材料牌号快速鉴别的目的.     

Modeling of a station in CVS and an approach to analyze distributions of time intervals of vehicles departed from the station

A stochastic model is developed for an off-line station with a single berth in a computer-controlled vehicle system (CVS). Distributions of time intervals with departures of four types of vehicles from the station are derived by using conditional first passage-times between states on an aggregated Markov chain. We show an algorithm to allow a convenient analysis.