Magnetic resonance butterfly coils: Design and application for hyperpolarized C studies

Hyperpolarized ¹³C magnetic resonance spectroscopy in pig models enables cardiac metabolism assessment and provides a powerful tool for heart physiology studies, although the low molar concentration of derivate metabolites gives rise to technological limitations in terms of data quality. The design of dedicated coils capable of providing large field of view with high Signal-to-Noise Ratio (SNR) data is of fundamental importance.     

An IR molding system for direct shaping of thermoplastics

A new molding technique is proposed to directly mold small parts from thermoplastic pellets. A small molding machine was designed and fabricated: the mold consisted of a transparent glass and a metallic frame; an infrared (IR) lamp provided the heat for the pellet melting. Molding tests were carried out by using three commercial thermoplastics and two metallic molds. Molding time and IR lamp power were changed to extract a moldability window for each combination of material and metallic mold. In the best process conditions, a high quality of the samples was obtained in terms of mold filling and surface aesthetics. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers     

Middle distillates from hydrocracking of FT waxes: Composition,characteristics and emission properties

A light cobalt catalyzed Fischer–Tropsch (FT) wax was subjected to hydrocracking in the range of temperature 319–351 °C and hydrogen pressure between 3.5 and 6.0 MPa. The catalyst used was platinum on amorphous silica–alumina. Hydrocracking reaction led to an increase of middle distillate yield up to 85% with a contemporary increase of iso-paraffins concentration which resulted in a remarkable improvement of cold flow properties of the products. The freezing point of C₁₀–C₁₄ fraction passed from ?23 to ?45 °C while the pour point of C₁₅–C₂₂ fraction decreased from 13 to ?23 °C. The latter fraction displayed high cetane numbers ranging between 75 and 80. Changes in carbon distribution and molecular structure of products during hydrocracking have been rationalized in the light of the accepted hydrocracking mechanism where n-paraffins undergo to consecutive isomerization reactions leading to isomers with progressively higher branching degree and concomitant cracking reaction. Experimental evidences support the view that apparent reactivity of n-paraffins is chain length dependent, increasing with the molecular weight. Detailed characterization by NMR and GC showed that branching groups abundance in the middle distillate products was the following: methyl ? ethyl > propyl.Emission tests carried out with FT diesel and commercial ultra low sulfur diesel showed that FT diesel has excellent combustion properties and leads to a reduction of emissions.     

Quantification of lycopene in tomato products: comparing the performances of a newly proposed direct photothermal method and high‐performance liquid chromatography

A new photothermal method suitable for direct, accurate and highly reproducible quantitative measurements of lycopene in tomato products has been introduced. The intrinsic precision of the method is typically better than 0.2%; the repeatability of determination is comparable to that of high‐performance liquid chromatography, with 0.86% least overall error. Copyright © 2005 Society of Chemical Industry     

Volatile compounds in table olives (Olea Europaea L., Nocellara del Belice cultivar)

Table olive quality depends on a number of factors, including fruit characteristics, ripening and processing technologies. Volatile and semi-volatile organic compounds, present both in the sample matrix and in the headspace aroma, are responsible for the olive fruit flavour influencing the consumer’s preference.     

Digital Median Filters

Several DSP algorithms need to remove high-frequency or impulsive noise while preserving edges, e.g., in speech and image processing applications: median filtering has been proved to be more effective for achieving this goal than other filtering techniques. Efficient architectural implementation for real-time applications involves a careful VLSI design, which takes into account modularity, regularity, adaptability, scalability, throughput, circuit complexity and fault tolerance. Four new architectural approaches are presented and evaluated in this paper to deal with different application and implementation constraints. They are: the serial-input polarizing median filter, the floating median filter, the pipelined polarizing median filter and the pipelined sorting median filter. The 1st and the 2nd architectures are based on majority voting, while the 3rd and the 4th ones are based on sorting techniques. All of them are designed so as to exhibit high scalability and to be easily pipelined for higher working frequencies.     

塔菜克·纳卡:空间思想的自由和严密

我首先想要对读者表明我对建筑学的观点。我试图强调如何将理念融入到空间的创造中。这不仅仅是一个建筑学问题，而且是全人类表达的一个组成部分。对于那些问“一个好建筑师需要研究些什么？”的人，有人回答是技术、有人回答是造型、还有人回答是形体学问题等等。我个人的感觉是：人，这个观点也被其他很多思索者所认同。我们再一次地发现，如果我们探寻什么，真理要比它看起来遥远得多，有时甚至看不到，而且从不确定和讨人喜欢。     

Lightweight validation of natural language requirements

In this paper, we report on our experiences of using lightweight formal methods for the partial validation of natural language requirements documents. We describe our approach to checking properties of models obtained by shallow parsing of natural language requirements, and apply it to a case study based on part of a NASA specification of the Node Control Software on the International Space Station. The experience reported supports our position that it is feasible and useful to perform automated analysis of requirements expressed in natural language. Indeed, we identified a number of errors in our case study that were also independently discovered and corrected by NASA's Independent Validation and Verification Facility in a subsequent version of the same document, and others that were not discovered. The paper describes the techniques we used, the errors we found and reflects on the lessons learned. Copyright © 2001 John Wiley & Sons, Ltd.     

Catalytic Synergism in a C60IL10TEMPO2 Hybrid in the Efficient Oxidation of Alcohols

A novel fullerene [5:1]hexakisadduct bearing two 2,2,6,6‐tetramethylpiperidine 1‐oxyl (TEMPO) radicals and ten 1‐propyl‐3‐methylimidazolium bromide moieties has been synthesized and characterized. Such an C₆₀IL₁₀TEMPO₂ hybrid has been successfully employed as a catalyst in the selective oxidation of a wide series of alcohols and is highly active at just 0.1 mol% loading. Moreover, it can be easily recovered by adsorption onto a multi‐layered covalently‐linked SILP phase (mlc‐SILP) through a “release and catch” approach and reused for up to 12 cycles without loss in efficiency. Interestingly, a catalytic synergistic effect of TEMPO and imidazolium bromide moieties combined in the same hybrid has been clearly shown.

     

聚集与向心：传统佛教建筑对场所精神的延续

“场所精神”早在古罗马的传统信仰文化中就有所体现,古罗马人认为,每一种“独立的”本体（包括人和场所）都有自己的灵魂（genius）守护神灵,灵魂赋予本体以生命,如影随形,始终决定其外在的特征并反映其内在的本质。从“genius loci”这个词的组合上就可以看出,“genius”表示“What a thing is”,即“物之为何”,意味着理解力（intel igence）或精神技能的最高水平,而“loci”则为“地点”、“场所”之意,又“特定已知存在的地方”或“某事物的中心所在”,合起来就成为了一个标识场所本质的词条。而在某种意义上讲,场所也被认为是“一个人记忆的一种物体化和空间化”,或是“对一个地方的认同感和归属感”。著名的城市建筑学家诺贝格·舒尔茨（Christian Norberg-Schulz）在1979年明确提出“场所精神”的概念,认为场所是具有清晰特性的空间。如今,“场所精神”经常被用来指具有与众不同的氛围的场所或地点,或者是某种“精神性的场所（spirit of place）”,而不仅仅指某一位守护神。而在同种类型的建筑当中,其“场所精神”所表现出的气质往往是相同的,以至于每一类别的建筑都有其共通的“场所精神”,反映着相似的内在本质。这也在一定程度上诠释了为什么具备同种精神职能的建筑能够赋予人们同样的心灵体验。通常情况下,建筑艺术通过一些相类似的外在特征来表现这种近乎“同一”的内涵。例如,传统佛教建筑就常常通过“聚集”或“向心”的符号象征来重现佛陀讲经说法时的场景,并表达宇宙人生的真相。无论何时何地,只要不偏离符号象征的原型（prototype）,这种“场所精神”就能够得到有效的延续。