THERMOPLASTIC,FLEXIBLE, AND RECYCLABLE COMPOSITES,DESIGN, PREPARATION,AND CHARACTERIZATION

Glass fiber reinforced composites based on thermosets are the traditional materials used for many applications due to their good mechanical properties. The non-recyclability of these materials has led to the necessity to develop thermoplastic composites and industrial processes for their manufacture [1]. The present paper deals with the preparation of thermoplastic pre-pregs unidirectionally reinforced with Twarn® and their mechanical characterization.     

DUO-ICP-AES测定精对苯二甲酸中的钴、铬、铁、锰、钼、镍、钛

采用DUO-ICP-AES同时测定精对苯二甲酸中钴、铬、铁、锰、钼、镍、钛,并对仪器的分析线选择、背景校正、入射功率、雾化器压力、辅助气流量、冷却气流量、蠕动泵转速的影响及共存元素的干扰、硝酸铯灰化助剂等因素进行了详细的研究。方法的检测限:钴0.0097 mg/L;铬0.0021 mg/L;铁0.0078 mg/L;锰0.0012 mg/L;钼0.0027 mg/L;镍0.016 mg/L;钛0.0027 mg/L,回收率和精密度分别为93.0%～99.5%和0.37%～3.2%。该方法快速简便,具有良好的精密度和准确度,适用于进出口精对苯二甲酸的日常检验。     

Pd-, Ni-, Fe-, and Co-Catalyzed Cross-Couplings Using Functionalized Zn-, Mg-, Fe-, and In-Organometallics

The development of new methods for preparing polyfunctional organometallics has made a broad range of such reagents available for various transition metal-catalyzed cross-couplings. An overview of the most general preparation methods will be presented. Applications to practical cross-coupling procedures will be covered, emphasizing the functional group compatibility and the reaction scope.     

Sylvatraxx树脂对半钢子午线轮胎胎面胶性能的影响

本文研究了Arizona Chemical公司生产的胎面增强助剂（Tread Enhancement Additive-TEA）Sylvatraxx 4401对半钢子午线轮胎胎面胶性能的影响。结果表明：Sylvatraxx 4401的加入有利于提高白炭黑的分散性,改善混炼胶的加工性能和硫化胶的物理机械性能,能够明显提高胎面的抗湿滑性。随着Sylvatraxx 4401用量的增加,白炭黑在胶料中的分散进一步提高,混炼胶的门尼粘度降低;硫化胶的压缩生热和阿克隆磨耗降低,0oC的tanδ明显提高的同时60oC的tanδ略微降低,有利于胎面胶抗湿滑性能的提高和滚动阻力、动态生热的降低。     

二苯并（2，3，2＇，3＇，bg）－1H，6H，1，4，6，9－四氮－5－钛螺环［4，4］－5，5－二氯化物

ｏ－苯二胺与四氯化钛反应合成聚合物的模型化合物钛杂咪唑啉。该化合物经元素分析、红外光谱、质谱测试。     

Preparation, Characterization, and Microwave Properties of RETiNbO6 (RE = Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Y, and Yb) Dielectric Ceramics

Microwave ceramic dielectric resonators (DRs) based on RETiNbO₆ (RE = Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Y, and Yb) have been prepared using the conventional solid-state ceramic route. The DR samples are characterized using XRD and SEM methods. The microwave dielectric properties are measured using resonant methods and a net work analyzer. The ceramics based on Ce, Pr, Nd, and Sm have dielectric constants in the range 32–54 and positive coefficient of thermal variation of resonant frequency (τ_f). The ceramics based on Gd, Tb, Dy, Y, and Yb have dielectric constants in the range 19–22 and negative τ_f.     

ICP-OES测定大量元素水溶肥料中锌、镁、铜、铁、锰、钼、硼含量

采用ICP-OES对大量元素水溶肥料中微量元素锌、镁、铜、铁、锰、钼、硼进行分析,研究确定了最佳分析条件。加标回收率为96.94%～106.2%,RSD为0.50%～1.40%,检出限为0.001 8～0.218 0 mg/L,方法简便、快速、准确。     

Fatty Acids,Tocopherols, Tocotrienols,Phytosterols, Carotenoids,and Squalene in Seed Oils of Hyptis suaveolens,Leonotis nepetifolia,and Ocimum sanctum

The oil yield and composition of fatty acids, tocopherols, tocotrienols, sterols, carotenoids, and squalene in the seeds of three species—Hyptis suaveolens, Leonotis nepetifolia, Ocimum sanctum—belonging to the Lamiaceae family, are studied. The oil yields are 12.1%, 16.1%, and 29.0% in O. sanctum, H. suaveolens, and L. nepetifolia, respectively. The unsaturated fatty acids are a predominant group (86.8–92.1%) in all three investigated plants; however, the profile for each species is unique. The main fatty acid differs as follows: H. suaveolens—linoleic acid (85.8%), L. nepetifolia—oleic acid (58.3%), and O. sanctum—α‐linolenic (48.6%). γ‐Tocopherol accounts for over 97%, 90%, and 93% of the total tocochromanol content (sum of tocopherols and tocotrienols) in H. suaveolens, L. nepetifolia, and O. sanctum, respectively. Two tocotrienol homologues, α and γ, are detected only in L. nepetifolia. β‐Sitosterol is the main detected sterol (38–59%) in all three species. High levels of campesterol (18–20%), Δ5‐stigmasterol (9–21%), and Δ5‐avenasterol (7–12%) are also detected. Squalene is detected only in O. sanctum (45.8 mg/100 g oil). The content of sterols, tocochromanols, and carotenoids in the investigated Lamiaceae plant seed oils ranges between 279.5–576.3, 54.5–66.7, and 0.3–3.1 mg/100 g oil, respectively. Practical Applications: Lamiaceae plants are of medicinal interest due to the presence of a broad spectrum of bioactive molecules. The present study demonstrates that seeds of the species H. suaveolens, L. nepetifolia, and O. sanctum are rich sources of bioactive compounds of lipophilic nature. There is limited knowledge associated with the composition of tocopherols, tocotrienols, sterols, carotenoids, and squalene. The results of the studied medicinal plants may enhance future targeted applications in various sectors.     

Antiferroelectrics: History,fundamentals, crystal chemistry,crystal structures,size effects,and applications

Antiferroelectric (AFE) materials are of great interest owing to their scientific richness and their utility in high-energy density capacitors. Here, the history of AFEs is reviewed, and the characteristics of antiferroelectricity and the phase transition of an AFE material are described. AFEs are energetically close to ferroelectric (FE) phases, and thus both the electric field strength and applied stress (pressure) influence the nature of the transition. With the comparable energetics between the AFE and FE phases, there can be a competition and frustration of these phases, and either incommensurate and/or a glassy (relaxor) structures may be observed. The phase transition in AFEs can also be influenced by the crystal/grain size, particularly at nanometric dimensions, and may be tuned through the formation of solid solutions. There have been extensive studies on the perovskite family of AFE materials, but many other crystal structures host AFE behavior, such as CuBiP₂Se₆. AFE applications include DC-link capacitors for power electronics, defibrillator capacitors, pulse power devices, and electromechanical actuators. The paper concludes with a perspective on the future needs and opportunities with respect to discovery, science, and applications of AFE.     

N,N''''-双甲基-N,N''''-双(2,3,4,5,6-五羟基正己基)-2,3,5,6-四碘对苯二甲酰胺的合成

以对苯二甲酸和碘为原料,50%发烟硫酸为溶剂,制得2,3,5,6-四碘对苯二甲酸,再通过氯化亚砜进行酰氯化,最后与葡甲胺反应合成了标题化合物.其结构通过元素分析、红外光谱、核磁共振氢谱,质谱得到确证.运用正交实验优化了酰胺化反应条件三乙胺为缚酸剂,四碘对苯二甲酰氯和葡甲胺为反应物,它们的物质的量比为2.112.4,反应温度为40℃时,产率高达71.5%.     

Continuous solvent extraction of sunflower,seed, groundnuts,palmkernels, rapeseed,and copra

In principle, the oil milling process is straightforward. The wide variety of equipment in use reflects, however, a multiparametric process. The main limiting parameters are kind of seed, oil content, particle strength, particle structure, temperature, moisture, particle size, residence time, mechanical forces, etc. Additionally, the seed specific parameters vary not only between kinds of seed but also for the same seed, due to different conditions in climate, soil, and harvesting. Therefore, equipment design must be widely based on statistical averages of the limiting parameters. In other words, exact precalculation of the single technological steps is impossible. As a consequence, for more than 5,000 years, the oil milling process has been in the stage of being optimized. The acutal technical standard is very satisfying, but there is still a strong need for further research and development. Currently, as in the past, the oil milling process seems to be not so much a science as an art.