GC法测定灵丹油清咽喷雾剂中β-芹子烯的含量

目的建立灵丹油清咽喷雾剂中β-芹子烯的含量测定方法。方法采用GC法,色谱柱为HP-5MS毛细管柱;检测器为FID;程序升温：初始温度80℃,保持2min,以每分钟2℃的速率升温至150℃,再以每分钟10℃的速率升温至200℃,保持8min。结果β-芹子烯在0.036875~0.4425μg范围内线性关系良好（r=0.9999,n=5）,平均回收率为98.44%,RSD为2.03%。结论本方法简便,重复性好,专属性强,可用于灵丹油清咽喷雾剂的质量控制。

巧妙“拨动”氢原子烯丙醇合成绿色高效

只需巧妙“拨动”一个烯烃的氢原子，烯丙醇类化合物高效绿色合成难题迎刃而解。日前，南开大学叶萌春团队借助廉价金属镍和苯基硼酸共催化的烯基化反应．克服传统生产过程中反应利用率低、环境污染大、反应产物不可控等问题，首次实现烯丙醇高效、绿色合成重大突破。

GC法测定灵丹草油中β-芹子烯的含量

目的:建立灵丹草油中β-芹子烯的含量测定方法。方法:采用气相色谱法,色谱柱为HP-5MS毛细管柱;检测器为FID;程序升温为初始温度80℃,保持2 min,以每分钟2℃的速率升温至150℃,再以每分钟10℃的速率升温至200℃,保持8 min。结果:β芹子烯在0.014 76～0.590 4μg线性关系良好(r=0.999 9,n=5),平均回收率为99.38%(n=5),RSD1.26%。结论:本实验方法可靠,重复性好,专属性强,可用于灵丹草油中β-芹子烯的含量测定,以控制灵丹草油的质量。

乙烯冷剂压缩机机械密封磨损计算

介绍了我国首例在乙烯“三机”（裂解气压缩机、丙烯冷剂压缩机和乙烯冷剂压缩机）中选用机械密封做轴封的乙烯冷剂压缩机的机械密封结构和使用条件。依据ＨＯＬＭ理论，推导出了机械密封磨损量的计算公式。

Ballistic Penetration Damage of Hybrid Thermoplastic Composites Reinforced with Kevlar and UHMWPE Fabrics

Polymer matrix types of fiber hybrid composites are key factors to improve ballistic impact damage tolerances.Here we report ballistic penetration damages of Kevlar/ultra-high molecular weight polyethylene(UHMWPE)hybrid composites with thermoplastic polyurethane(PU)matrix.The hybrid composites were penetrated by fragment-simulating projectiles(FSPs)using an air gun impact system.The effects of stacking sequences on the ballistic performance of hybrid composites were analyzed.Two types of specific energy absorption(the energy absorption per unit area density and the energy absorption per unit thickness)were investigated.It was found that the main damage modes of PU hybrid composites were fiber breakage,matrix damage,fiber pullout and interlayer delamination.The instantaneous deformation could not be used as a reference index for evaluating the ballistic performance of the target plate.The energy absorption process of the PU hybrid composites showed a nonlinear pattern.The hybrid structure affected the specific energy absorption of the materials.

Study on the Mechanism of Nanopatterning in Printed Electronics Based on Molecular Dynamics Simulation

In order to research the feasibility of using the selective adsorption principle to achieve automatic shaping of nano patterns,in this study,using the liquid gallium as the conductive ink and graphene as the printing plate surface,by changing the surface wettability of patterned areas on the nanoscale of graphene printed boards,the automatic formation of liquid gallium patterns on the graphene printed plate surface was simulated.The results indicated that liquid gallium can achieve automatic patterning on the surface of graphene patterned areas;the greater the interaction energy between gallium and carbon atoms,the clearer the pattern;gallium liquid is prone to remain in complex local positions of the pattern,making it difficult to shape the pattern;if the spacing between adjacent pattern lines is too large or too small,it will result in residual gallium liquid between the lines;increasing the thickness of the gallium film will cause the pattern to expand beyond the boundary,but increasing the thickness of the gallium film can also enhance the thickness and uniformity of the pattern lines.In summary,the principle of selective adsorption can be used to achieve the automatic formation of nano patterns,and the pattern formation effect is influenced by factors such as atomic interaction energy and pattern configuration.

一种新的生化类型的樟树叶油成分分析

利用GC-MS联用仪和GC对樟树2-32#水蒸气蒸馏提取的樟叶油进行了定性和定量分析,鉴定出19个组分,主要为单萜类和倍半萜类及其氧化物,其主要成分为6-芹子烯-4醇,含量高达69.39%。根据相关文献表明,6-芹子烯-4醇型是樟树叶油中的一种新的生化类型。

UV-Vis法测定灵丹草油中总萜类含量

目的建立测定灵丹草油中总萜类含量的方法。方法以β-芹子烯为对照,用5%香草醛-冰乙酸溶液、高氯酸显色,在555 nm波长处测定吸收度。结果β-芹子烯检测浓度在0.0309～0.13095mg·mL-1范围内与吸收度呈良好线性关系(r=0.9990),平均回收率为99.38%,RSD=1.23%(n=6)。结论本方法简便、准确,可用于灵丹草挥发油的质量控制。

Effects of Ethephon on Flowering of Ornamental Pineapple in Guzmania

[Objective] This study aimed to establish the technical system for forcing ornamental pineapple in Guzmania to flower and further provide technical parameters for large-scale cultivation.[Method] The effect of different concentrations of ethephon solution on flowering in Guzmania ornamental pineapple was studied by using randomized block design.[Results] All the different concentrations of ethephon solution were capable to force the four mainly-cultivated ornamental pineapple varieties to flower to varying degrees.After the flower forcing,it took about 180 d for the pineapple to stay in the ornamentation period,and there were no significant differences in inflorescence shape,inflorescence height,inflorescence diameter and bract number among different treatment pineapples.[Conclusion] All the four varieties have shown high sensitivity to ethephon.The optimal ethephon concentration is 400 mg/L for treating G.lingulata,G.remembrance and G.denise and 500 mg/L for treating G.conifera.After treatment,their major ornamentation traits are were able to satisfy the requirements for commercial production of pineapple.

One-pot facile synthesis of highly photoluminescent graphene quantum dots with oxygen-rich groups

To achieve a new type of carbon-based quantum dots with unique photoluminescence PL a simple approach for fabrication of graphene quantum dots GQDs with oxygen-rich groups was developed via the hydrothermal reaction by using graphene oxides GOs as a precursor. Transmission electron microscope TEM and atomic force microscope AFM characterizations confirmed that the sizes and heights of GQDs were 5.02±0.92 nm and 0.6 nm respectively.A strong PL emission exhibited unique excitation wavelength dependent features.Also the carbene-like free zigzag edge sites were proposed to be the origin of the strong PL emission.The GQDs were demonstrated to be a superior probe for Fe3＋ detection in aqueous solution with a high sensitivity and feasibility due to the special coordinate interaction between Fe3＋and the phenolic hydroxyl group at GQDs.

Synthesis and characterization of an unusual snowflake-shaped ZSM-5 zeolite with high catalytic performance in the methanol to olefin reaction

The ZSM-5 zeolite with an unusual snowflake-shaped morphology was hydrothermally synthesized for the first time,and compared with common ellipsoidal and boat-like shaped samples.These samples were characterized by N2 adsorption-desorption,X-ray fluorescence spectroscopy,scanning electron microscopy,X-ray diffraction,magic angle spinning nuclear magnetic resonance,temperature-programmed desorption of ammonia,and infrared spectroscopy of pyridine adsorption.The results suggest that the BET surface area and SiO2/Al2O3 ratio of these samples are similar,while the snowflake-shaped ZSM-5 zeolite possesses more of the（101） face,and distortion,dislocation,and asymmetry in the framework,resulting in a larger number of acid sites than the conventional samples.Catalysts for the methanol to olefin（MTO） reaction were prepared by loading Ca on the samples.The snowflake-shaped Ca/ZSM-5 zeolite exhibited excellent selectivity for total light olefin（72%） and propene（39%） in MTO.The catalytic performance influenced by the morphology can be mainly attributed to the snowflake-shaped ZSM-5 zeolite possessing distortion,dislocation,and asymmetry in the framework,and lower diffusion limitation than the conventional samples.

栀子总环烯醚萜苷对脑出血大鼠内皮屏障的影响

目的:探讨栀子总环烯醚萜苷对脑出血大鼠内皮屏障的影响。方法:SD大鼠随机分为假手术组、模型组和栀子总环烯醚萜苷(30、15和5mg/kg)组,采用自体血注入诱发大鼠脑出血模型,术后24、48、72和120h时间点各组各取10只大鼠脑组织标本,采用免疫组织化学染色检测脑出血周围血肿组织中内皮屏障抗原(endothelial barrier antigen,EBA)和血管内皮整合素αVβ3(αVβ3-Integrin)表达,ELISA法测定促血管生成素-1(angiopoietin-1,Ang-1)和血栓调解蛋白(Thrombomodulin,TM)含量变化。结果:与假手术组比较,术后24～120h模型大鼠脑血肿周围组织中EBA免疫消失区面积增多,整合素αVβ3平均光密度值增加,Ang-1和TM浓度升高。与模型组比较,30mg/kg栀子总环烯醚萜苷组在术后24～120h各时间点EBA免疫消失区面积和整合素αVβ3表达降低,Ang-1和TM浓度降低。15mg/kg栀子总环烯醚萜苷组仅在术后24～72h有效。结论:栀子总环烯醚萜苷可保护或修复内皮屏障,减少EBA消失区面积和整合素αVβ3表达,降低Ang-1和TM水平。

SYNTHESIS AND APPLICATION OF NEW DETERGENT BUILDER POLYACRYLATE SODIUM

The low molecular weight polyacrylate sodium (PAA Na) detergent builder was synthesized with K 2S 2O 8 as initiator in a neutral aqueous medium. The influences of reaction conditions on the viscosity average molecular weight were studied. The critical value of synthetic PAA Na inhibiting the precipitation of CaCO 3 was determined and compared with that of other common builders. It is confirmed from SEM graphs that PAA Na can make CaCO 3 crystal defective. Washing tests show synthetic PAA Na can partially replace sodium tripolyphosphate (STPP) and is a potential polymeric detergent builder in low phosphate powder detergents.

STUDY ON DEGRADATION OF POLYETHYLENE FILMS CONTAINING ADDITIVES WITH FERROUS ION AT COMPOSTING TEMPERATURES

Polyethylene (PE) films with additives consisting mainly of oleic acid and ferrous ions were subjected to accelerated degradation at simulated composting temperatures.Based on Fourier transform infrared spectroscopy and measurements of mechanical properties and viscosity average molecular weight,the degradation of the films was characterized and the degradation mechanism was discussed.The films containing additives with ferrous ions represent considerable decreases in molecular weight,and the carbonyl groups and hydroperoxides in the aging films show different trends of increase with the aging time.These results indicate that the ferrous ion plays an important role in the degradation of PE films and accelerates the degradation of PE.

The Effect of Silane Grafted Polypropylente on the Property of Different Filler/Polypropylene Composites

Aim To determine the effect of silane grafted polypropylene on the property of different filler/polypropylene composites. Methods Polypropylene (PP) composites filled with talc(Ta), baryta sulfate and calcium carbonate coupled with silane grafted polypropylene (PP-g-Si) were made, their mechanical properties and thermal properties were investigated, respectively. Results As compared with the non-coupled composites, the mechanical properties of PP/Ta/PP-g-Si composites were improved to some extent, though the values of tensile modulus and the strain at peak were decreased. But for PP/BaSO4 and PP/CaCO3 composites, the values of their mechanical properties varied slightly or even decreased with increasing PP-g-Si content within the experimental component. Meanwhile, PP-g-Si also affected the melting and crystallization behavior of PP in the composites. Conclusion PP-g-Si offers compatibilization in PP/Ta composites, but offers no-compatibilization in PP/BaSO4 and PP/CaCO3 composites within the extent of the present range of PP-g-Si, which shows that PP-g-Si can be used as the macromolecular coupling agent of PP and Ta composite.

Effect of Paclobutrazol plus Ethephon Treatment on Endogenous Hormones and Carbon and Nitrogen Nutrients in Litchi Variety ‘Feizixiao'

[Objective] This study aimed to investigate the effect of spraying the mixture of paclobutrazol and ethephon on the endogenous hormones and carbon and nitrogen nutrients in litchi variety ＇Feizixiao＇.[Method] [Result] The results showed that foliar spraying of the mixture of paclobutrazol and ethephon could effectively inhibit litchi variety ＇Feizixiao＇ to produce winter shoots,promote the flower bud differentiation and improve flower formation rate; meanwhile,this treatment could also increase the contents of ABA and ZR,and the ratios of ABA/IAA,ABA/GA3,ZR/IAA,ZR/GA3,and decrease the contents of IAA and GA3; additionally,it could increase the contents of soluble sugar,starch and total nitrogen,and raise C/N ratio,thus improving the flower formation rate.[Conclusion] Foliar spraying of the mixture of paclobutrazol and ethephon is an effective pathway for solving warmth damage to litchi.

Ultrasonic synthesis of CoO/graphene nanohybrids as high performance anode materials for lithium-ion batteries

A facile ultrasonic method was used to synthesize CoO/graphene nanohybrids by employing Co4（CO）12 as a cobalt precursor. The nanohybrids were characterized by SEM, TEM and XPS, and the results show that CoO nanoparticles （3-5 nm） distribute uniformly on the surface of graphene. The CoO/graphene nanohybrids display high performance as an anode material for lithium-ion battery, such as high reversible lithium storage capacity （650 mA-h/g after 50 cycles, almost twice that of commercial graphite anode）, high coulombic efficiency （over 95%） and excellent cycling stability. The extraordinary performance arises from the structure of the nanohybrids： the nanosized CoO particles with high dispersity on conductive graphene substrates are beneficial for lithium-ion insertion/extraction, shortening diffusion length for lithium ions and improving conductivity, thus the lithium storage performance was improved.

Numerical simulation of diffusion process for oxidative dehydrogenation of butene to butadiene

A comprehensive single particle model which includes the mesoscale and microscale models was developed to study the influence of particle diameter on mass and heat transfer occurring within a ferrite catalyst during the oxidative dehydrogenation of butene to butadiene process. The verified model can be used to investigate the influence of catalyst diameter on the flow distribution inside the particle. The simulation results demonstrate that the mass fraction gradients of all species, temperature gradient and pressure gradient increase with the increase of the particle diameter. It means that there is a high intraparticle transfer resistance and strong diffusion when applying the large catalysts. The external particle mass transfer resistance is nearly constant under different particle diameters so that the effect of particle diameter at external diffusion can be ignored. A large particle diameter can lead to a high surface temperature, which indicates the external heat transfer resistance. Moreover, the selectivity of reaction may be changed with a variety of particle diameters so that choosing appropriate particle size can enhance the production of butadiene and optimize the reaction process.

贮藏期间芒果汁芳香成分的变化

对贮藏2和4个月的瓶装芒果汁进行分析,以了解有害果汁品质的芳香物的变化情况。85℃下果汁经10分钟加热处理,蒸发使所有挥发性馏份含量降低,并生成乙酰呋喃、5-甲基糠醛、β-萜品醇、萜品烯-4-醇和丁基-3-羟基丁酸酯,这些化合物在鲜果汁内是没有的。它们的出现归因于降解反应,尤其是维生素C。室温下贮藏瓶装芒果汁,除碳氢化合物和氧化合物含量降低外,还生成乙基脂肪酸和芹子烯-11-4醇,从而影响芒果汁风味。瓶装芒果汁热处理和贮藏产生的不利因子是呋喃衍生物,α-和β-萜品醇,萜品烯-4-醇以及脂肪酸乙酯。

Convenient synthesis of silver nanoplates with adjustable size through seed mediated growth approach

Silver nanoplates,with average thickness about 5 nm and average tunable size from 40 to 500 nm,were synthesized via a simple room-temperature solution-phase chemical reduction method in the presence of appropriate concentration of trisodium citrate and silver seeds.The optical in-plane dipole plasmon resonance bands of these silver plates could be tuned from 520 to 1100 nm.Control experiments were explored for understanding of the growth mechanism.It is found that both the amount of citrate ions and the small silver seeds added to the growth solution are the key to controlling the silver nanoplates without changing their thickness and crystal structure.Small silver seeds are found to play an important role in the formation of large thin silver nanoplates when poly（vinylpyrrolidone）（PVP） are used as capping agent.