射频磁控溅射SiOx薄膜的制备与阻隔性能研究

利用磁控溅射技术,以SiO2为靶材,Ar为射频源气体,在PET基材上制备SiOx薄膜.研究了不同放电功率、氩气流量、镀膜时间等参数对SiOx薄膜阻隔性能的影响.结果表明:在一定范围内,薄膜的阻隔性能随放电功率的增大而增大,而后逐渐减小;氩气流量对薄膜的阻隔性能也有一定影响;镀膜时间在10min时SiOx薄膜的阻隔性能最好.扫描电镜SEM测试表明,在氩气流量为100cm3/min,镀膜时间10min,1500W放电功率下制备的SiOx薄膜阻隔性能较好、表面较均匀.     

SiOx/PET复合薄膜的力学性能及阻隔性能

目的基于氧化硅(SiO_x)镀层优异的性能,研究不同厚度的SiO_x层对SiO_x/PET复合薄膜力学性能和阻隔性能的影响,以期得到性能较优的SiO_x/PET复合薄膜。方法以自制的聚对苯二甲酸乙二醇酯(PET)薄膜为基材,采用等离子体增强化学气相沉积法沉积得到SiO_x层厚度分别为40,150,230,320 nm的SiO_x/PET复合薄膜,并进行傅里叶变换红外线光谱分析、力学性能和阻隔性能测试,以及薄膜表观形貌分析。结果沉积SiO_x层后,SiO_x/PET复合薄膜拉伸强度和断裂伸长率随SiO_x层厚度的增大先增大后减小,氧气透过率和水蒸气透过率则出现明显衰减而后逐渐平缓的趋势。SiO_x层厚度达150~230 nm时,复合薄膜的力学性能和阻隔性能表现较优,拉伸强度、断裂伸长率、氧气透过率以及水蒸气透过率分别提高了约25.0%,20.9%,79.3%,77.3%。结论适宜厚度的SiO_x层可以使得SiO_x/PET复合薄膜同时具备较优的力学性能和阻隔性能。     

单体对制备SiOx高阻隔包装薄膜的影响

本文论述在食品包装保质保鲜方面,对普通包装基材PET,BOPP等表面采用等离子体化学气沉积一层纳米级透明的SiOx层高阻隔层。实验分别以四甲基二硅氧烷（TMDSO）和六甲基二硅氧烷（HMDSO）为单体,氧气为反应气体,氩气为电离气体,在载玻片,单晶硅片,PET,BOPP等包装基材上演积硅氧阻隔膜。比较了不同单体在制备氧化硅阻隔膜时各种工艺参数对薄膜的阻隔性能影响。     

特种阻隔包装材料Si-O-N薄膜的制备

以六甲基二硅氧烷（HMDSO）和四甲基硅氧烷（TMDSO）为单体,以氧气以及氮气为反应气体,以氩气为电离气体,在载玻片、单晶硅片、PET等基材上采用13.56MHz射频等离子体聚合装置沉积硅氧氮薄膜。在薄膜的制备工艺中,通过改变各种工艺参数制备阻隔薄膜并研究所制备硅氧氮薄膜的性能。通过傅立叶红外光谱仪（FTIR）表征分析沉积膜的化学组成,采用透湿、透氧测试仪测试薄膜的阻隔性能,探讨工艺参数的变化对薄膜表面的成分和阻隔性能影响以及氮的加入对薄膜柔韧性的影响。     

聚合单体对制备SiOx高阻隔性薄膜性能的影响

论述在食品包装保质保鲜方面,对普通包装基材PET、BOPP等表面采用等离子体化学气沉积一层纳米级透明的SiOx层高阻隔层.实验采用13.56MHz的射频等离子体装置,分别以四甲基二硅氧烷(TMDSO)和六甲基二硅氧烷(HMDSO)为单体、氧气为反应气体、氩气为电离气体,在载玻片、单晶硅片、PET、BOPP等包装基材上沉积硅氧阻隔膜.比较了不同单体在制备氧化硅阻隔膜时各种工艺参数影响.通过傅立叶红外谱仪(FTIR)分析,扫描电子显微镜(SEM)表征,研究沉积膜的化学组成和结合状态;采用透湿测试仪测试薄膜的透湿性能,研究工艺参数的变化、表面的结构变化、形貌改变等对薄膜的阻隔性能影响原因.     

SiOx包装阻隔薄膜的发展现状及其制备方法

SiOx阻隔薄膜具有优异的阻隔性,并且光透过性和微波透过性好,在阻隔包装领域的应用前景广泛,介绍了SiOx包装阻隔薄膜的制备方法:物理气相沉积,等离子体聚合及大气下等离子体聚合等.     

射频等离子体化学气相沉积(RF-PECVD)制备Si-O-N特种阻隔包装材料的研究

采用13.56MHz射频等离子体聚合装置,以六甲基二硅氧烷(HMDSO)和四甲基硅氧烷(TMDSO)为单体、氧气以及氮气为反应气体、氩气为电离气体,在载玻片、单晶硅片、PET等基材上沉积硅氧氮薄膜.在薄膜的制备工艺研究中,通过改变放电工作压强、放电功率、沉积时间和氧气、氮气、氩气和单体的比例等,研究所制备硅氧氮薄膜的性能.通过傅立叶红外光谱仪(FTIR)表征分析沉积膜的化学组成;采用透湿、透氧测试仪测试薄膜的阻隔性能,探讨工艺参数的变化对薄膜表面的成分和阻隔性能影响以及氮的加入对薄膜柔韧性的影响.     

MPECVD中氧化硅阻隔层性能的研究

介绍了用磁增强等离子体化学气相沉积技术在连续(Roll-to-Roll)系统中,在PET薄膜表面沉积纳米SiOx阻隔层薄膜的工艺。研究了不同工艺条件下,薄膜的阻隔性能、颜色变化及其影响因素。实验得到:在单体和氧气的混合反应气体中,提高氧气的比例有利于增加薄膜透明性,并且得到的氧化硅膜由黄褐色趋近于无色透明。通过红外光谱仪对薄膜的成分进行了分析,用分光光度计和紫外可见分光光度计测量了薄膜颜色和透明性变化,分析了其影响产生的机理。     

缠绕式射频磁控溅射聚(PET)表面沉积氧化硅(SiOx)薄膜的研究

采用缠绕式射频磁控溅射方法在PET表面沉积SiOx薄膜.研究了制备工艺对薄膜组成、表面形貌、阻隔性能的影响.通过红外光谱(FITR)、扫描电子显微镜(SEM)、原子力显微镜(AFM)观察分析了射频功率、工作压强等参数对SiOx薄膜性能的影响,得到最佳工艺参数;通过透湿与透氧测试,2000W、0.7Pa得到SiOx薄膜对水蒸汽的阻隔性提高了约15倍,对氧气的阻隔性提高了25倍.     

ZnO 薄膜包装材料溅射制备工艺与阻隔性能研究

目的为了解决普通聚合物包装塑料对水、氧的阻隔能力不足,以及包装内容物货架时间短等问题,研究氧化锌(ZnO)沉积复合薄膜制备工艺与阻隔性能之间的关系,探索其应用于包装材料的可行性。方法采用射频磁控溅射技术(RF),以ZnO为靶材,在PET塑料表面沉积制备氧化锌薄膜包装材料,并详细分析射频溅射功率、沉积时间与工作气压对ZnO复合薄膜微观形貌、沉积速率以及阻隔性能的影响。结果当溅射功率为150 W,沉积时间为30 min,工作气压为0.8 Pa时,ZnO薄膜均匀且致密,阻隔能力最强,其氧气透过率(OTR)降低为1.23 m L/(m2·d),水蒸汽透过率(WVTR)降低为0.382 g/(m2·d)。与相同厚度下的PET原膜相比,所制备的ZnO高阻隔薄膜的透氧率降低了49.5倍,透湿率降低了17.6倍。结论射频溅射参数通过影响复合薄膜的微观形貌、致密程度、沉积速率以及沉积层厚度等方面对其阻隔能力会产生较大影响。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...     

Effect of Oxide Assisted Metal Nanoparticles on Microstructure and Morphology of Gallium oxide Nanowires

Several researches have been reported about the characteristic of β-Ga2O3 nanowires which was synthesized on nickel oxide particle. But indeed, recent researches about synthesis of β-Ga2O3 nanowires on oxide-assisted transition metal are limited to nickel or cobalt oxide catalyst. In this work, Gallium oxide (β-Ga2O3 ) nanowires were synthesized by a simple thermal evaporation method from gallium powder in the range of 700 - 1000℃ using the iron, nickel, copper, cobalt and zinc oxide as a catalyst, respectively. The β-Ga2O3 nanowires with single crystalline without defects were successfully synthesized at the reaction temperature of 850, 900 and 950℃ in all the catalysts. But optimum experimental condition in synthesis of nanowires varied with the kind of catalyst. As increasing synthesis temperature,the morphology of gallium oxide nanowires changed from nanowires to nanorods, and its diameter increased. From these results, we could be proposed that the growth mechanism of β-Ga2O3 nanowires was changed with synthesis temperature of nanowires. Microstructure and morphology of Synthesized nanowire was characterized by HR-TEM, FE-SEM, EDX and XRD.     

The Influence of Nitrogen and Boron Implant into Silicon Substrate on the Phase and Internal Stress of c-BN Films

Cubic boron nitride(c-BN) film was deposited on a Si (100) substrate by the RF-magnetron sputtering.The mainly problems for fabrication of c-BN films are the low purity and high intrinsic compressive stress. In order to solve the two problems, the c-BN film with the buffer interlayer was deposited on the substrate which had been implanted with nitrogen and/or boron ions. The results show: the implantation of nitrogen ions can obviously increase c-BN content and reduce the internal stress slightly; while the implantation of boron shows no obvious improvement to the content of c-BN, which can reduce the internal stress in the film obviously. In addition, it is suggested that the implantation of nitrogen and boron shows the best result, which not only can increase the content of c-BN, but also reduce the internal stress in the c-BN film obviously.