Functional copolymer of geraniol and acrylonitrile: Synthesis and characterization

The radical copolymerization of acyclic terpene namely geraniol [GER] with acrylonitrile [AN] in DMF at (70 ± 0.1)°C for 1 h, using benzoylperoxide (BPO) as an initiator has been carried out under inert atmosphere of nitrogen. The kinetic expression for reaction is R_p ∝ [BPO]^0.5 [AN]^1.0 [GER]^1.0. The IR spectrum of the copolymer shows bands at 3432 and at 2244 cm^?1 due to ? OH group of GER and ? CN group of AN, respectively. The ¹³C‐NMR spectrum shows peaks at 73–75 δ ppm and 116–120 δ ppm due to ? OH group of GER and ? CN group of AN, respectively. The thermogravimetric analysis and differential scanning calorimetry study shows that copolymer is thermally stable up to 407°C and has glass transition temperatures (T_g) 56°C. The reactivity ratios r₁ (AN) and r₂ (GER) have been calculated as 0.05 and 0.005, respectively. The Alfrey‐Price Q‐e parameter for GER has been calculated as 0.094 and ?2.0, respectively. The molecular weights of the copolymers have been evaluated by gel‐permeation chromatography. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

"Learning myopia: An adaptive recency effect in category learning": Correction to Jones and Sieck (2003).

Reports an error in "Learning myopia: An adaptive recency effect in category learning" by Matt Jones and Winston R. Sieck (Journal of Experimental Psychology: Learning, Memory, and Cognition, 2003[Jul], Vol 29[4], 626-640). On page 633, Table 2, the values in columns (T, P) and (P, T) in the dual condition row incorrectly read .10 and .90, respectively. The correct values are .90 and .10, respectively. (The following abstract of the original article appeared in record 2003-06626-013.) Recency effects (REs) have been well established in memory and probability learning paradigms but have received little attention in category learning research. Extant categorization models predict REs to be unaffected by learning, whereas a functional interpretation of REs, suggested by results in other domains, predicts that people are able to learn sequential dependencies and incorporate this information into their responses. These contrasting predictions were tested in 2 experiments involving a classification task in which outcome sequences were autocorrelated. Experiment 1 showed that reliance on recent outcomes adapts to the structure of the task, in contrast to models' predictions. Experiment 2 provided constraints on how sequential information is learned and suggested possible extensions to current models to account for this learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reconstruction of reflectance spectra using weighted principal component analysis

The weighted principal component analysis technique is employed for reconstruction of reflectance spectra of surface colors from the related tristimulus values. A dynamic eigenvector subspace based on applying certain weights to reflectance data of Munsell color chips has been formed for each particular sample and the color difference value between the target, and Munsell dataset is chosen as a criterion for determination of weighting factors. Implementation of this method enables one to increase the influence of samples which are closer to target on extracted principal eigenvectors and subsequently diminish the effect of those samples which benefit from higher amount of color difference. The performance of the suggested method is evaluated in spectral reflectance reconstruction of three different collections of colored samples by the use of the first three Munsell bases. The resulting spectra show considerable improvements in terms of root mean square error between the actual and reconstructed reflectance curves as well as CIELAB color difference under illuminant A in comparison to those obtained from the standard PCA method. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 360–371, 2008     

用核磁共振技术确定岩石孔隙结构的实验研究

目前核磁共振技术对岩石的孔隙结构进行评价还停留在定性评价阶段。虽然多数核磁实验室开展了核磁共振评价孔隙结构的研究工作，建立了转换模型，但由于转换系数无法有效地确定，还不能进行应用。通过对岩心核磁共振T2谱与压汞孔径分布的对比，建立了转换模型系数与孔渗比的关系，同时考虑了顺磁物质对转换系数的影响，提出了确定转换模型系数的方法，为核磁共振技术进行孔隙结构的定量评价提供了新的方法。     

激光角膜矫正术中所用激光波长的选择

用分光光度计测定了12例兔角膜和1例人角膜的吸收光谱,结果表明波长小于300nm的准分子激光和波长在1.88μm～2.64μm,2.36μm～40μm的激光,均可对角膜进行切割并可望用于激光角膜矫正术。     

Data requirements for neutron activation: Part I: Cross sections

Existing neutron cross section libraries such as EAF-2003 contain a large number of reactions. Of these only a small proportion are significant in the production of the nuclides that dominate activation quantities such as activity or γ-dose rate at various decay times. These reactions were identified in a recent extensive set of calculations on all the elements and reported in the ‘Activation Handbook’. These 1340 reactions are considered here and the set of reactions with no differential or integral data are listed and prioritised. A set of 339 reactions with very limited possibility of measurement are given; these require further study by theoretical calculations. A set of 100 reactions with either discrepant or no data, that might be measurable are listed and are recommended to be the subject of future experimental work.     

TiO_2-聚乙烯复合膜的制备及红外光谱对其膜层结构的表征

开发了以Ｔｉ４＋为桥联剂制备无机－有机复合膜的新方法以自制的硅藻土多孔陶瓷为基膜（支撑体），使用浸涂法－热致相转化法相结合制备了ＴｉＯ２－聚乙烯复合膜，并用红外光谱表征了复合膜层与层之间的结合方式和强度，支撑体中的ＳｉＯ２通过Ｔｉ４＋与聚乙烯的分子之间形成了新的化合物型膜层     

Optical pattern recognition using two-channel joint transform correlation

A new joint transform correlation (JTC) technique, named two-channel JTC (TJTC), is proposed in this paper for optical pattern recognition applications. The TJTC technique independently evaluates the autocorrelation and crosscorrelation values of the reference and the target images and employs a modified decision algorithm. In addition, optical threshold operation and fringe-adjusted filter are incorporated in the proposed technique to enhance the correlation output and to improve the discrimination performance. The proposed technique shows better recognition performance compared to existing JTC techniques. Computer simulation are presented to investigate the salient features of the proposed TJTC technique with noise-free as well as noisy input scenes. The text was submitted by the authors in English.     

同时含有稀土元素La Ce Pr Nd的材料的电子探针定量分析方法

研制了稀土六硼化物单晶LaB_6、CeB_6、PrB_6和NdB_6电子探针分析标样。根据X-射线峰位表和实测的特征X-射线谱,考察分析了La、Ce、Pr和Nd元素谱线之间的干扰情况,发现分析谱线PrLα_1受到L_αLβ_1线严重的干扰。以混合稀土金属为试样,采用扣除谱线重叠强度的背底非对称测量等方法对L_n、Ce、Pr和Nd进行了电子探针定量分析,其结果与荧光X-射线光谱分析结果符合较好。     

The use of the stable isotope 44Ca in studies of calcium incorporation into dentin

The incorporation into rat incisor dentin of two calcium isotopes, the stable ⁴⁴Ca and the radioactive ⁴⁵Ca, was studied using secondary ion mass spectrometry (SIMS) stepscanning and imaging, and autoradiography, respectively. The results demonstrated a time-dependent incorporation of the calcium isotopes into the mineral phase of dentin. With the SIMS step-scanning, detecting ⁴⁴Ca, the ion yield was high in the odontoblasts 2 min after intravenous injection. After 10 min a marked increase in signal intensity was found at the dentin mineralization front. This result was consistent with those obtained by ⁴⁵Ca autoradiography; a peak of incorporation occurred 10 min after injection of the isotope. Likewise, localization of ⁴⁴Ca to the mineralization front could be demonstrated 10 min after injection by SIMS imaging. In images obtained at earlier intervals, no such increase in ion yield could be detected. The results show that the nonradioactive, stable isotope ⁴⁴Ca can be used as a marker for biomineralization in a similar way to radioactive ⁴⁵Ca.