Identification of TAG and DAG and their FA Constituents in Lesquerella (Physaria fendleri) Oil by HPLC and MS

Castor oil has many industrial uses because of its high content (90 %) of the hydroxy fatty acid, ricinoleic acid (OH¹²18:1⁹). Lesquerella oil containing lesquerolic acid (Ls, OH¹⁴20:1¹¹) is potentially useful in industry. Ten molecular species of diacylglycerols and 74 molecular species of triacylglycerols in lesquerella (Physaria fendleri) oil were identified by electrospray ionization mass spectrometry as lithium adducts of acylglycerols in the HPLC fractions of lesquerella oil. Among them were: LsLsO, LsLsLn, LsLsL, LsLn–OH20:2, LsO–OH20:2 and LsL–OH20:2. The structures of the four new hydroxy fatty acid constituents of acylglycerols were proposed by the MS of the lithium adducts of fatty acids as (comparing to those in castor oil): OH¹²18:2^9,14 (OH¹²18:2^9,13 in castor oil), OH¹²18:3^9,14,16 (OH18:3 not detected in castor oil), diOH^12,1318:2^9,14 (diOH^11,1218:2^9,13 in castor oil) and diOH^13,1420:1¹¹ (diOH20:1 not detected in castor oil, diOH^11,1218:1⁹ in castor oil). Trihydroxy fatty acids were not detected in lesquerella oil. The differences in the structures of these C18 hydroxy fatty acids between lesquerella and castor oils indicated that the polyhydroxy fatty acids were biosynthesized and were not the result of autoxidation products.     

Street Life and the ‘People’s City’

Could large-scale urban development and an erosion of rights to public space prove the death knoll for China’s vibrant street life? Shi Jian , Planning Director of ISreading Culture in Beijing, looks at the tradition of Chinese street culture and how it is currently shifting and reinventing itself for new urban contexts. Copyright © 2008 John Wiley & Sons, Ltd.     

Oxirane Cleavage Kinetics of Epoxidized Soybean Oil by Water and UV‐Polymerized Resin Adhesion Properties

Di‐hydroxylated soybean oil (DSO), a biobased polyol synthesized from epoxidized soybean oil (ESO) could be used to formulate resins for adhesives; however, current DSO synthesis requires harsh reaction conditions that significantly increase both cost and waste generation. In this paper, we investigate the kinetics of oxirane cleavage in ESO to DSO by water and elucidate the role of different process parameters in the reaction rate and optimization of reaction conditions. Our kinetic study showed that ESO oxirane cleavage was a first‐order reaction and that the ESO oxirane cleavage rate was greatly influenced by tetrahydrofuran (THF)/ESO ratio, H₂O/ESO ratio, catalyst content, and temperature. Optimized reaction parameters were THF/ESO of 0.5, H₂O/ESO of 0.25, catalyst content of 1.5 %, and reaction time of 3 h at 25 °C. DSO with hydroxyl value of 242 mg KOH/g was obtained under these conditions. We also characterized the structure, thermal properties, adhesion performance, and viscoelasticity of UV‐polymerized resins based on this DSO. The resin tape exhibited peel adhesion strength of 3.6 N/in., which is comparable to some commercial tapes measured under similar conditions.     

Synthesis,Characterization and Properties of <Emphasis Type="Italic">N</Emphasis>-Alkyl-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-di(2-hydroxyethyl) Amine Oxides

N‐Dodecyl‐N,N‐di(2‐hydroxyethyl) amine oxide (C₁₂DHEAO) and N‐stearyl‐N,N‐di(2‐hydroxyethyl) amine oxide (C₁₈DHEAO) were synthesized with N‐alkyl‐diethanolamine and hydrogen peroxide. Their chemical structures were confirmed using ¹H‐NMR spectra, mass spectral fragmentation and FTIR spectroscopic analysis. It was found that C₁₂DHEAO and C₁₈DHEAO reduced the surface tension of water to a minimum value of approximately 28.75 mN m^?1 at concentration of 2.48 × 10^?3 mol L^?1 and 32.45 mN m^?1 at concentration of 5.21 × 10^?5 mol L^?1, respectively. The minimum interfacial tension (IFT_min) and the dynamic interfacial tension (DIT) of oil–water system were measured. When C₁₈DHEAO concentration was in the range of 0.1–0.5%, the IFT_min between liquid paraffin and C₁₈DHEAO solutions all reached the ultra‐low interfacial tension. Furthermore, their foam properties were investigated by Ross‐Miles method, and the height of foam of C₁₂DHEAO was 183 mm. It was also found that they showed strong emulsifying power.     

食品塑料包装材料中邻苯二甲酸二（2-乙基己）酯的暴露评估

文中主要综述了食品塑料包装材料所用邻苯二甲酸酯类增塑剂中,邻苯二甲酸二（2-乙基己）酯（DEHP）的性质、来源、毒性及危害。提出了预防措施和建议,为食品塑料包装材料的安全陛以及包装食品的安全陛的相关研究提供参考依据。     

Applying design metrics to predict fault‐proneness: a case study on a large‐scale software system

The purpose of this study was to identify fault‐prone functions that are likely to contain faults in a given software system. Five metrics were used: D_i, an internal design metric which incorporates factors related to a function's internal structure; D_e, an external design metric which focuses on a function's external relationships to the rest of the software system; D(G), a composite design metric which is a linear combination of D_i and D_e; and the union and intersection of D_i, D_e, and D(G). Since the system being considered was already developed, a very important aspect of our study was to extract the design information directly from the source code rather than from the corresponding design documentation which may not exist or, if it does exist, it may be incomplete, difficult to understand, or not updated. To make the analysis more accurate and efficient, a metric analysis tool (χMetrics) was implemented. We conducted experiments using χMetrics on part of a distributed software system, written in C, with a client–server architecture, and identified a small percentage of its functions as good candidates for fault‐proneness. Files containing these functions were then validated by the real defect data collected between a recent major release and its subsequent release for their fault‐proneness. The results indicate that our metrics are good indicators of fault‐prone functions. Two extra experiments were also conducted to show that function size cannot replace any of our metrics; and where the function size was factored out our metrics performed better than the normalized metrics. The important benefit of our metrics is that they help project managers determine where additional testing effort should be spent and possibly which fault‐prone functions should be assigned to more experienced programmers if modifications are required. Copyright © 2000 John Wiley & Sons, Ltd.     

叠氮二乙基铝的性能及应用

ＤＥＡＡ是一种新型化工材料,具有广阔的应用前景。本文综合论述了ＤＥＡＡ的结构、性能、合成方法及应用。     

催化酯化合成邻苯二甲酸二辛酯的新进展

介绍了邻苯二甲酸二辛酯生产现状,催化酯化反应的新型催化剂及催化剂制备方法。     

Separation of Eu（III） with supported dispersion liquid membrane system containing D2EHPA as carrier and HNO3 solution as stripping solution

The Eu(III) separation in supported dispersion liquid membrane (SDLM),with polyvinylidene fluoride membrane (PVDF) as the support and dispersion solution containing HNO3 solution as the stripping solution and Di(2-ethylhexyl) phosphoric acid (D2EHPA) dis-solved in kerosene as the membrane solution,was studied.The effects of pH value,initial concentration of Eu(III) and different ionic strengths in the feed phase,volume ratio of membrane solution and stripping solution,concentration of HNO3 solution,concentration of carrier,different stripping agents in the dispersion phase on the separation of Eu(III) were also investigated,respectively.As a result,the optimum separation conditions of Eu(III) were obtained as the concentration of HNO3 solution was 4.00 mol/L,concentration of D2EHPA was 0.160 mol/L,and volume ratio of membrane solution to stripping solution was 30:30 in the dispersion phase,and pH value was 5.00 in the feed phase.Ionic strength had no obvious effect on the separation of Eu(III).Under the optimum conditions studied,when initial concentration of Eu(III) was 1.00×10–4 mol/L,the separation rate of Eu(III) was up to 94.2% during the separation period of 35 min.The kinetic equation was developed in terms of the law of mass diffusion and the theory of interface chemistry.The results were in good agreement with the literature data.     

昌化鸡血石"地"的研究及其质量影响因素

在野外地质调查的基础上,对不同品种昌化鸡血石的"地"进行了常规宝石学特征鉴定、X射线粉末衍射以及红外光谱的分析测试。研究结果表明,昌化鸡血石"地"的主要矿物成分及其质量分数是影响其质量的重要因素,呈明显的规律性和过渡性:地开石的质量分数越高,结构有序度越好,其"地"的质量就越好;随着明矾石的加入,"地"的透明度逐渐变差,摩氏硬度也增大;伴随明矾石的增多以及石英的加入,昌化鸡血石的"地"从"软地"过渡到"刚地";当石英的质量分数达到25%以上时,昌化鸡血石的"地"则属于质量较差的"硬地"。