Investigation of an Egyptian Mummy board by Using Clinical Multi-slice Computed Tomography

A modern approach to the diagnosis of artistic heritage makes use of non-destructive techniques which avoid damage to artworks or signs of interaction with the analytical technique used. For this reason, today, the employment of X-rays to study artistic heritage is quite widespread. Computed tomography (CT) Imaging was first used as specialized medical diagnostic tool in the early 1970s. Today, CT scanners have become more common, and non-destructive three-dimensional imaging has found an increasing number of uses in different areas such as materials research, geology, archaeology, and museum conservation. In this work, a new generation of clinical CT (based on the Dual Energy and multi-slice acquisition principle) is used to investigate an Egyptian wooden mummy board with a total acquisition time of 93.23 seconds and a voxel size of 0.078?×?0.078?×?1.5?mm. The use of two distinct techniques of image post-processing, the two-dimensional multi-planar reconstruction (MPR) and the three-dimensional volume rendering technique (VRT) allowed us to: evaluate the state of conservation of the mummy board, determine how the wooden object was implemented, recognize a nineteenth-century intervention of consolidation, and advance the hypothesis that the wooden planks were reused. In particular, we highlight the use of the cardiovascular and pulmonary filter with VRT reconstruction, which allows a virtual elimination of different parts of the mummy board to investigate those areas otherwise accessible only by removing parts of the board and thus damaging the work.     

Measurement of conversion efficiency of soft X-ray from 0.35μm laser-irradiated aluminum planar targets

Conversion efficiency of soft X-ray from 0.35 μm pulse laser-irradiated aluminium planar target at laser intensities 10¹³–10¹⁵ W/cm² on the Xingguang-II facility (laser energy 5–90 J, focal spot ⊃ Ф 200 μm full width of half maximun (FWHM) 400–800 ps) was measured. A simple model was given to explain soft X-ray conversion efficiency. In this model, because of the heat conduction from the laser-heated spot, the conversion was very small at lower irradiance limit, while at higher limit it was bounded by the energy lost in blow off plasma. Consequently, at the laser intensity around 2×10¹⁴ W/cm², the X-ray conversion efficiency reaches a maximum. Project suppoted by Shanghai Leading Academic Discipline Foundation (Grant No. T0104), and Science Foundation of Shanghai Municipal Commission of Education (Grant No. 214680)     

溴化（E）-1,1′-（六烷-1,6-二甲氨基）二（4-（E）-2-（噻吩基）乙烯基吡啶的合成、表征及光电性质的研究

合成和表征了一个新的吡啶衍生物溴化（E）-1,1′-（六烷-1,6-二甲氨基）二（4-（E）-2-（噻吩基）乙烯基吡啶,这是一种自组装膜合成的中间配体,具有特殊的结构特征和氧化还原性,以其为配体继续合成自组装膜材料,在共价和静电自组装膜研究的领域有很高的研究价值,本文对它的合成、表征及其紫外可见光谱和荧光光谱等的性质作一研究。     

不同品种黄瓜幼苗光合机构对盐胁迫的响应

研究了盐胁迫(0、25、50mmol／L)对不同品种黄瓜幼苗生长、光合作用和叶绿素荧光的影响．结果表明，盐胁迫，尤其是高浓度NaCl(50mmol／L)的胁迫，显著降低黄瓜幼苗生长量、叶绿素含量、光系统Ⅱ光合电子传递量子效率(φPSⅡ)、净光合速率(Pn)、气孔导度(Gs)以及气孔限制值(Ls)，同时显著提高叶片相对电导率、丙二醛、脯氨酸含量和细胞间CO2浓度(Ci)，光系统Ⅱ的光化学效率(Fv／Fm)变化不大．盐胁迫对耐盐黄瓜‘津研4号’幼苗生长的影响小于盐敏感黄瓜‘津绿4号’，这可能与耐盐黄瓜在盐胁迫下较高的净光合速率、光系统Ⅱ光合电子传递量子效率和较低的丙二醛(MDA)含量、相对电导率有关。     

柴油机喷雾特性的电喷控制电路设计

介绍了一种柴油机电控喷油器喷射开启控制系统。为实现柴油机电控喷油器的开启、持续喷油、关闭功能,应用STC12系列单片机构成电控喷油器的控制系统。开启时为使喷油器开启迅速,应用单周期控制技术的IR1150S芯片,产生高压为112 V的高压电源为喷油器供电。试验结果表明,开发的柴油机电控喷油器控制系统符合X光相衬成像技术研究柴油机喷雾雾化机理的要求,喷油开启迅速、喷油持续稳定、关闭干脆。本系统根据设定可实现电控喷油器的单次及多次连续开启,进一步可以推广应用于柴油机喷油器相关环节教学实验中。     

实验教材中“荧光光谱法测定水杨酸”的讨论

为改进教材《荧光光谱法测定水杨酸》,寻找实验所需溶剂CHCl3的替代药品。通过实验,采用1%HAc-CHCl3、1%HAc-C2H5OH、1%HAc-H2O对荧光光谱法测定水杨酸的影响进行比较,并确定1%HAc-C2H5OH为其中最佳溶剂。     

南方菟丝子寄生对喜旱莲子草叶片光合特性的影响

以盆栽的喜旱莲子草（Alternanthera philoxeroides）为实验材料,研究了南方菟丝子（Cuscuta australis R.Br.）寄生对喜旱莲子草叶片光合特性的影响。结果表明,南方菟丝子寄生致使喜旱莲子草叶片的净光合速率（Pn）、蒸腾速率（E）、气孔导度（Gs）、水分利用率（WUE）、气孔限制值（Ls）、Fm值、Fv/Fm值和相对叶绿素含量都呈现明显的下降,而胞间CO2浓度（Ci）和Fo值表现出相反的趋势。南方菟丝子的寄生减弱了喜旱莲子草的光合作用,而净光合速率的下降主要是由非气孔因素限制引起的。     

荧光光谱法研究黄豆苷原与牛血清白蛋白的相互作用

用荧光光谱法在pH7.4的PBS中研究了黄豆苷原（Daidzein,Da）与牛血清白蛋白（bovine serum albu-min,BSA）的相互作用.结果表明Da可静态猝灭BSA的内源荧光,温度升高时受动态猝灭的影响变得明显.二者之间的结合位点数约为1.5,315 K、310 K,300 K和290 K时的表观结合常数分别为5.44×104L.mol-1,5.70×104L.mol-1,5.29×104L.mol-1和5.69×104L.mol-1.焓变为0.2969 kJ.mol-1,熵变为91.78为J.mol-1.K-1,各温度下的自由能变均小于零,热力学参数表明二者之间主要靠静电力发生作用,熵变对反应过程具有较大贡献,且反应是自发过程.同步荧光光谱表明Da的加入改变了BSA的构像,使色氨酸残基的微环境亲水性增强.本研究对于阐明Da与蛋白的相互作用机理具有借鉴意义.     

分峰计算结晶度的问题探讨

应用分峰方法计算结晶度,首要条件是结晶聚合物的形态结构必须符合"两相模型"。通过聚合物材料的分析,发现Jade软件的分峰程序固然很好,但其受到扫描范围、基线、非晶峰位置及分布的影响很大,计算的结晶度值有一定的随意性,只能作相对比较,且结晶度值偏大。用X射线衍射法测定的结晶度与其他实验方法获得的结晶度无可比性,还常遇到背景散射的基线不平和非晶峰难以确定等现象。对此进行探讨和交流。     

Estimating fat-free mass in elite-level male rowers: a four-compartment model validation of laboratory and field methods

The purpose of this study was to investigate the accuracy of fat-free mass (FFM) estimates from two-compartment (2C) models including air displacement plethysmography (ADP), ultrasound (US), near-infrared interactance (NIR), and the Jackson and Pollock skinfold equation (SKF) against a criterion four-compartment (4C) model in elite male rowers. METHODS: Twenty-three elite-level male rowers (mean± SD; age 24.6 ± 2.2 years; stature: 191.4 ± 7.2 cm; mass: 87.2 ± 11.2 kg) participated in this investigation. All body composition assessments were performed on the same day in random order, except for hydrostatic weighing (HW), which was measured last. FFM was evaluated using a 4C model, which included total body water from bioimpedance spectroscopy, body volume from HW, and total body bone mineral via dual-energy X-ray absorptiometry. The major findings of the study were that the 2C models evaluated overestimated FFM and should be considered with caution for the assessment of FFM in elite male rowers. Future studies should use multiple-compartment models, with measurement of TBW and bone mineral content, for the estimation of FFM.