RADIATION OR WAXING EFFECT ON SHELF LIFE OF GUAVA FRUIT

Red and white guavas were treated with wax emulsion or irradiation (0.25-2.0 kGy) and kept for 12 days at room temperature. Initiation of rot attack occurred after 3 days which increased significantly during further storage. In the waxed fruits rottage, weight loss and vitamin loss were significantly less than controls and irradiated ones. Sensory scores decreased with storage time and they ranged 3.7-4.5, 2.1-3.9 and 2.3-2.7 in waxed, radiated and untreated controls respectively, after 12 days storage. Waxing was found to increase the. shelf life of this fruit for 3-4 d while irradiation exhibited no beneficial effects.

美国双河纸业公司推出Acadia Waxing涂蜡包装纸

双河纸业（TwinRiversPaper）公司开发了一种可以用于干蜡和湿蜡的最佳包装纸AcadiaWaxing。

Efficacy Evaluation Method of Hair Removal Cream

To explore the efficacy evaluation method of depilatory cream.60 subjects were selected as subjects,and statistical analysis was carried out on the depilation effect of large samples.The hair was removed with a razor in the control area and with depilation cream in the sample area,Antera 3D skin imaging analyzer was used to image the experimental area before and after the experiment,and the hair growth was dynamically monitored at 7,14,21 and 28 days,measure the length of hair with instrument and measure the number of people.The hair length change rate and hair inhibition rate were dynamically monitored in 28 days.The hair length change rate was-10.5%and hair inhibition rate was 93.3%after 28 days,more intuitive display of the product depilation effect,so as to determine the efficacy of depilation products evaluation method.

The ZOS7-MYB60 module confers drought-stress tolerance in rice

Shanlan upland rice is an important landrace resource with high drought stress(DS)tolerance.Despite its importance,genes responsible for yield in Shanlan upland rice have yet to be discovered.Our previous study identified a drought-responsive zinc finger protein,ZOS7,as highly expressed in Shanlandao upland rice.However,the function of this gene in controlling drought tolerance remains largely unexplored.In this study,we found that overexpressing ZOS7,a drought-responsive zinc finger protein,in rice increased biomass and yield under drought stress.Co-overexpressing ZOS7 and MYB60,encoding a protein with which ZOS7 interacted,intensified the yield increase.ZOS7 and MYB60 appear to form a module that confers drought tolerance by regulating stomatal density and wax biosynthesis.The ZOS7-MYB60module could be used in molecular breeding for drought tolerance in rice.

Probing the interaction between asphaltene-wax and its effects on the crystallization behavior of waxes in heavy oil via molecular dynamics simulation

High content of asphaltenes and waxes leads to the high pour point and the poor flowability of heavy oil,which is adverse to its efficient development and its transportation in pipe.Understanding the interaction mechanism between asphaltene-wax is crucial to solve these problems,but it is still unclear.In this paper,molecular dynamics simulation was used to investigate the interaction between asphaltenewax and its effects on the crystallization behavior of waxes in heavy oil.Results show that molecules in pure wax are arranged in a paralleled geometry.But wax molecules in heavy oil,which are close to the surface of asphaltene aggregates,are bent and arranged irregularly.When the mass fraction of asphaltenes in asphaltene-wax system(ω_(asp))is 0-25 wt%,the attraction among wax molecules decreases and the bend degree of wax molecules increases with the increase ofω_(asp).Theω_(asp)increases from 0 to 25 wt%,and the attraction between asphaltene-wax is stronger than that among waxes.This causes that the wax precipitation point changes from 353 to 333 K.While theω_(asp)increases to 50 wt%,wax molecules are more dispersed owing to the steric hindrance of asphaltene aggregates,and the interaction among wax molecules transforms from attraction to repulsion.It causes that the ordered crystal structure of waxes can't be formed at normal temperature.Simultaneously,the asphaltene,with the higher molecular weight or the more hetero atoms,has more obvious inhibition to the formation of wax crystals.Besides,resins also have an obvious inhibition on the wax crystal due to the formation of asphalteneresin aggregates with a larger radius.Our results reveal the interaction mechanism between asphaltene-wax,and provide useful guidelines for the development of heavy oil.

Differences in leaf cuticular wax induced by whole-genome duplication in autotetraploid sour jujube

Drought-resistant plants exhibit strong water retention capability.In this regard,the autotetraploid sour jujube leaves exhibit better water retention than diploid leaves.Morphological comparisons and physiological comparisons of diploid and autotetraploid leaves showed that the autotetraploid leaves had thicker leaf cuticles and more leaf wax accumulation than the diploid leaves,which could reduce cuticle permeability and improve the drought tolerance of leaves.In this study,the cuticular wax crystalloids on the adaxial and abaxial sides of young and mature jujube leaves were observed in the two ploidy types,and unique cuticular wax crystalloids covering a large area of the cuticle on autotetraploid sour jujube leaves may provide an advantage in reducing leaf non-stomata transpiration and improving plant drought tolerance.Based on the transcriptome,115 differentially expressed genes between diploids and autotetraploids were further analyzed and found to be involved in the accumulation of cuticular wax components,including terpenoids,fatty acids,and lipids,as well as ABC transporter and wax biosynthetic process.Finally,14 genes differentially expressed between glossy autotetraploid leaves and nonglossy diploid leaves,such as LOC107414787,LOC107411574 and LOC107413721,were screened as candidate genes by qRT-PCR analysis.This findings provided insights into how polyploidization improved drought tolerance.

Inhibition of wax crystallization and asphaltene agglomeration by core-shell polymer@SiO_(2) hybride nano-particles

The gelation of crude oil with high wax and asphaltene content at low temperatures often results in the block of transportation pipeline in Africa. In recent years, it was reported that surface hydrophobicmodified nanoparticles have important applications in crude oil flow modification. In this work, four kinds of core-shell hybride nanoparticles by grafting poly(octadecyl, docosyl acrylate) and poly(acrylate-α-olefin) onto the surface of nano-sized SiO_(2) were synthesized by grafting polymerization method.The chemical structure of nanoparticles was analyzed by Fourier transform infrared spectroscopy(FT-IR),scanning electron microscopy(SEM) and thermogravimetric analysis(TGA). The rheological behaviors of crude oil and precipitation of asphaltenes in the presence of nanoparticles were studied by measuring the viscose-temperature relationship curve, the cumulative wax precipitation amount, and morphology of waxes and asphaltenes. The results indicate that the docosyl polyacrylate@SiO_(2) nanoparticle(PDA@SiO_(2)) can reduce the cumulative wax precipitation amount of crude oil by 72.8%, decline the viscosity of crude oil by 85.6% at 20℃, reduce the average size of wax crystals by 89.7%, and inhibit the agglomeration of asphaltene by 74.8%. Therefore, the nanoparticles not only adjust the crystalline behaviors of waxes, but also inhibit the agglomeration of asphaltenes. Apparently, core-shell hybride nanoparticles provides more heterogeneous nucleation sites for the crystallization of wax molecules,thus inhibiting the formation of three-dimensional network structure. The core-shell polymer@SiO_(2) hybride nanoparticles are one of promising additives for inhibiting crystallization of waxes and agglomeration of asphaltenes in crude oil.

Experimental study on wax deposition of highly paraffinic oil in intermittent gas-oil flow in pipelines

Oil-gas two phase wax deposition is a fairly common and open-ended question in flow assurance of multiphase transportation pipelines.This paper investigated the two main aspects of oil-gas two phase wax deposition layer:apparent thickness and crystal structure characteristics.A typical highly paraffinic oil in Bohai Sea,China,was used as the experimental material to investigate the wax deposition thickness in oil-gas two phase under the influence of different oil temperatures,superficial gas/liquid phase velocities and gas-oil ratios by using multiphase flow loop experimental device.Just as in the classical theory of wax molecular diffusion,it showed that wax deposition thickness of oil-gas two phase increased with increasing oil temperature.Analysis of the impact of different superficial phase velocities found that the actual liquid flow heat transfer and shear stripping was the gas phase dominant mechanisms determining wax deposit thickness.In addition,the crystal structure of the wax deposition layer was characterized with the help of small-angle X-ray scattering(SAXS)for different circumferential positions,flow rates and gas-oil ratios.The bottom deposition layer had a complex crystal structure and high hardness,which were subject to change over flow rate variations.Furthermore,the SAXS results provided evidence that the indirect effect of the actual liquid velocity modified by the gas phase was the main mechanism.Our study of the effect of gas phase on the wax deposition of oil-gas two phase will help shed light onto the mechanism by which this important process occurs.Our findings address a very urgent need in the field of wax deposition of highly paraffinic oil to understand the flow security of oilgas two phase that occurs easily in multiphase field pipelines.

The effect of ethylene-vinyl acetate copolymer on the formation process of wax crystals and hydrates

Ethylene-vinyl acetate copolymer(EVA) as a kind of effective polymeric pour point depressant has been extensively used in the pipeline transportation of crude oil to inhibit wax deposition and improve the low temperature fluidity of crude oil. In this work, molecular dynamics simulations were performed to investigate the effect of EVA on wax-hydrate coexistence system to evaluate the application potentiality of EVA to the flow assurance of deep-sea oil-gas-water multiphase flow system. Our simulation results reveal that wax molecules gradually stretched and stacked from random coiling to a directional and ordered crystalline state during the process of wax solidification. The strong affinity of polar vinyl acetate side chains of EVA to neighboring water molecules made the EVA molecule prefer being in a curly state,which disrupted the ordered crystallization of surrounding wax molecules and delayed the solidification rate of wax cluster. In addition, it is found that EVA cocrystallized with wax molecules to form eutectic when the wax was fully solidified. The simulation results of hydrate nucleation and growth show that the EVA molecule displayed a two-sided effect on gas adsorption of wax crystals, which was the key factor that affected the nucleation and growth of hydrates in the methane-water system. The nonpolar hydrocarbon backbone of EVA increased the diffusion rate of methane and water, allowing more methane to diffuse to the surface of wax crystals, reducing the methane concentration in aqueous solutions and inhibiting the hydrate formation. On the other hand, the nonpolar vinyl acetate chains had a repulsive effect on methane, which reduced the adsorption area of methane on the eutectic surface and decreased the adsorption threshold value of the wax crystal. The excluded methane molecules would continue dissociating in the aqueous phase and participating in the nucleation and growth process of hydrates.Therefore, the probability of hydrate formation would be increased. It was worth noting that the inhibition performance of EVA on hydrate formation mainly played a significant role in the system with small wax crystal, while its hydrate promotion effect played a dominant role in the system with lager wax crystal. In summary, EVA could significantly inhibit both of the wax and hydrate deposition for the waxgas-water multiphase system with low wax content. When the wax content in the system was high, the role of EVA was mainly played in the alleviation of wax crystallization rather than the gas hydrates. The results of the present work can contribute to a better understanding of EVA on wax deposition and hydrate formation, and provide theoretical support of the potential industrial applications of EVA.

ZmCER1,a putative ECERIFERUM 1 protein in maize,functions in cuticular wax biosynthesis and bulliform cell development

The cuticular wax,acting as the ultimate defense barrier,is essential for the normal morphogenesis of plant organs.Despite this importance,the connection between wax composition and leaf development has not been thoroughly explored.In this study,we characterized a new maize mutant,ragged leaf4(rgd4),which exhibits crinkled and ragged leaves starting from the sixth leaf stage.The phenotype of rgd4 is conferred by ZmCER1,which encoding an aldehyde decarbonylase involved in wax biosynthesis.ZmCER1 function deficient mutant displayed reduced cuticular wax density and disordered bulliform cells(BCs),while ZmCER1 overexpressing plants exhibited the opposite effects,indicating that ZmCER1 regulates cuticular wax biosynthesis and BCs development.Additionally,as the density of cuticular wax increased,the water loss rate of detached leaf decreases,suggesting that ZmCER1 is positively correlated with plant drought tolerance.

Investigation of the effect of hydrocarbons and monoesters in the gelators’composition on the properties of edible oleogel

Natural wax gelators have different compositions of compounds(hydrocarbons,wax esters,free fatty alcohols,and free fatty acids),which results in oleogels with varying properties.To maintain a consistent composition,the individual components can be added to the original wax gelator.The content of hydrocarbons and wax esters greatly affects the structuring process of liquid edible oils with waxes.The aim of this study was to evaluate the possibility of modifying the properties of beeswax as a gelling agent by adding hydrocarbons or monoesters to obtain oleogels with specific properties.Various tests were conducted to assess the changes in the oleogel properties,such as color,microstructure,oil-binding capacity,thermal and textural properties.The research results have shown that the addition of the studied fractions has led to a significant change in all properties of oleogels.The initial size of oleogel crystals(7.29±1.80μm)changed after adding fractions,varying from 5.28μm to 12.58μm with hydrocarbons and from 9.95μm to 30.41μm with wax esters.The addition of 30%–50% hydrocarbons decreased the ability of the oleogels to bind oil and made them less firm compared to samples with 10%-20% hydrocarbons.Adding 10%-20% monoesters increased the firmness of the oleogels,but this indicator decreased when their content was increased to 50%.The obtained data indicate that hydrocarbons and wax esters can be used for targeted correction of the gelling properties of beeswax.

Prediction Model of Wax Deposition Rate in Waxy Crude Oil Pipelines by Elman Neural Network Based on Improved Reptile Search Algorithm

A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines.To ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax deposition in crude oil pipelines.Aiming at the shortcomings of the ENN prediction model,which easily falls into the local minimum value and weak generalization ability in the implementation process,an optimized ENN prediction model based on the IRSA is proposed.The validity of the new model was confirmed by the accurate prediction of two sets of experimental data on wax deposition in crude oil pipelines.The two groups of crude oil wax deposition rate case prediction results showed that the average absolute percentage errors of IRSA-ENN prediction models is 0.5476% and 0.7831%,respectively.Additionally,it shows a higher prediction accuracy compared to the ENN prediction model.In fact,the new model established by using the IRSA to optimize ENN can optimize the initial weights and thresholds in the prediction process,which can overcome the shortcomings of the ENN prediction model,such as weak generalization ability and tendency to fall into the local minimum value,so that it has the advantages of strong implementation and high prediction accuracy.

涂装高浸透WAX应用说明

主要介绍了高浸透WAX材料的特性,以及基于现有设备基础进行相关的设备改造及注意事项。

偏岭石与变高岭石微结构的区别

采用广角度 X射线衍射 -散射 ( WAXS)测试技术和由此得到的径向分布函数 ( RDF) ,研究了偏岭石与变高岭石的结构差异 .结果表明 ,变高岭石是由非晶相和少量结晶相物质组成的半晶物质 ,而偏岭石是由非晶相和中间序态组成的准晶物质 .虽然两者均以非晶质相为主 ,并具有相似的近程结构模型 ,但在非晶质相中近邻八面体的连结方式和近邻四面体的连结有序性方面仍存在较大差异 .此外 。

Determination of wax pattern die profile for investment casting of turbine blades

In order to conform to dimensional tolerances, an efficient numerical method, displacement iterative compensation method, based on finite element methodology （FEM） was presented for the wax pattern die profile design of turbine blades. Casting shrinkages at different positions of the blade which was considered nonlinear thermo-mechanical casting deformations were calculated. Based on the displacement iterative compensation method proposed, the optimized wax pattern die profile can be established. For a A356 alloy blade, substantial reduction in dimensional and shape tolerances was achieved with the developed die shape optimization system. Numerical simulation result obtained by the proposed method shows a good agreement with the result measured experimentally. After four times iterations, compared with the CAD model of turbine blade, the total form error decreases to 0.001 978 mm from the orevious 0.515 815 mm.

南方红豆杉叶挥发性成分

分别以二氯甲烷和乙醚作溶剂,采用低温冷凝,同时蒸馏萃取南方红豆杉干叶挥发性成分,极性色谱柱(DB-WAX)气-质联机分析。鉴定出63种化合物,主要是脂肪族类(39种),其次为芳香族类(11种),而萜类化合物占比例很小(6种)。按两种萃取溶剂所得分析结果平均值,主要成分是十六烷酸(21.19%)、十四烷酸(8.87%)、亚麻酸乙酯(3.49%)。相比已有的关于南方红豆杉叶油成分分析的报道,新鉴定出己醛、2-己烯醛、1-辛烯-3-醇、2,4-庚二烯醛、苯乙酮等34种有青香、花香、果香香气的微量或痕量低沸点化合物。所鉴定化合物以邻二氯苯为内标定量,总含量为88.16μg/g红豆杉叶。

Steedman’s wax包埋切片DAPI染色法证实铝诱导花生根尖细胞程序性死亡

【目的】检验Steedman’swax包埋切片DAPI染色法是否适用于观察花生根尖细胞核形态。【方法】分别采取100μmol/L AlCl3处理不同时间(0、4、8、12 h)后两个花生品种(铝敏感型中花2号和耐铝型99-1507)的根尖,经过Steedman’s wax包埋切片等一系列过程,利用荧光染料DAPI染色观察细胞核形态变化。【结果】100μmol/L AlCl3可引起花生根尖细胞核形态发生改变,核质浓缩、核边缘化、呈新月状等,具有明显的PCD特征。花生根尖细胞在铝胁迫下发生PCD,PCD程度与花生耐铝性呈负相关,与处理时间呈正相关。【结论】Steedman’swax包埋切片DAPI染色法是一种快速、高效的适用于观察花生根尖细胞核形态的方法。

草菇子实体发育过程中担子细胞内的核相变化观察

运用Steedman's wax包埋切片法制备了草菇(Volvariella volvacea)子实体不同发育时期(小纽扣期、大纽扣期、蛋形期、伸长期、破膜期和开伞期)的菌褶切片并运用荧光显微镜和激光共聚焦显微镜观察了担子细胞核相变化情况。结果表明该方法可清晰观察到草菇担子细胞中核相以及在减数分裂中的变化、担子上孢子幼体、孢子梗、囊状体和孢子内细胞核等结构。草菇子实体小纽扣期细胞核成对进入担子细胞中;在大纽扣和蛋形期担子细胞基部发生核融合;伸长期、破膜期和开伞期的担子细胞内可观察到符合减数分裂特征的细胞核分裂前期Ⅰ、末期Ⅰ、前期Ⅱ和间期Ⅱ。通过对草菇担子细胞内细胞核减数分裂过程的观察,丰富了对草菇生活史的微观细胞学认识,为草菇有性生活史的深入研究提供了更多的科学依据。

用对称透射二维WAXS强度研究PET取向非晶态结构

用对称透射法，测试聚酯（PET）取向非晶试样的二维广角X射线散射相干强度Ie（K，α），将不同方位角α上的Ie（K，α）非晶重叠峰曲线进行计算机分解，获得分子链间原子散射引起的二个峰为A（K＝0．126）、B（K＝0．169）；分子链内原子散射引起的五个峰分别为C（K＝0．304）、D（K＝0．553）、E（K＝0．374）、F（K＝0．465）、G（K＝0．606），K单位为nm－1．分析了它们的结构起源以及主要峰参数与α的关系，得到PET取向非晶态的细微结构信息．

无机聚合絮凝剂的结构研究

本文用广角度Ｘ射线散射（ＷＡＸＳ）和径向分布函数（ＲＤＦ）方法对聚合硅硫酸铝钾ＴＸ２０３絮凝剂的结构进行了分析。ＷＡＸＳ和 ＲＤＦ分析指出：该絮凝剂是一种有序尺寸（Ｄ）约为 ２２－２５Ａ非晶固体。它是由有序周期（ｒ１）＝１２－１４Ａ的中程有序畴组成的。而这些有序畴又是由三种结构单元，即四面体［ＳＯ４］，［ＡＩＯ４］（Ｏ＝Ｏ，ＯＨ）和八面体［ＡＩＯ６］（Ｏ＝Ｏ，ＯＨ）组成的。Ｄ／ｒ１＝２～３，因此ＴＸ２０３是一种低聚体。在ＴＸ２０３絮凝剂中Ｓｉ有增强结构序性的作用。