利用卷式膜分离器分离有机蒸气／氮气混合气的过程研究

利用硅橡胶（ Ｌ Ｔ Ｖ）／ 聚醚酰亚胺（ Ｐ Ｅ Ｉ） 复合膜做成的卷式膜分离器,进行了有机蒸气（ Ｖ Ｏ Ｃ）／ 氮气混合气分离过程的研究,主要考察了原料气的处理量、浓度、压力以及渗透侧真空度对有机蒸气脱除率的影响．实验结果表明,当压力为０ ．６ Ｍ Ｐａ ,处理量为１ ．０３ ｍ ３／ｈ ,渗透侧真空度为０ ．０２ Ｍ Ｐａ 时,有机蒸气的脱除率达到９０ ％ 以上;提高原料气侧的压力以及在渗透侧抽真空,都可以使脱除率增加     

1-(2-甲硫嘧啶)-2-(4-硝基苯基)乙炔化合物的合成及其二阶非线性光学性能

根据Ｄｅｗａｒ和ＰＯＭ规则设计并采用Ｐｄ（０）及Ｐｄ（Ｉ）催化末端炔键氢和卤素原子进行偶联反应，再与炔铜反应合成的嘧啶环代单炔ＭＳＮＡ化合物，具有较大的分子共轭体系，因其星组碳被电负性更强的氮原子所取代，具有可在蓝紫光波段广泛应用的二阶非线性光学性能。     

增效膨胀阻燃聚乙烯的制备与性能研究

将ＺＥＯ（分子利）作为膨胀阻燃增效剂,分别引入ＡＰＰ／ＰＥＲ（聚磷酸铵／季戊四醇）和ＡＰＰ／ＤＰＥＲ（聚磷酸胺／双季戊四醇）两个ＩＦＲ（膨胀型阻燃剂）中,用于阻燃ＰＥ。结果表明：这一方法显著提高了ＩＦＲ的阻燃效率,ＩＦＲ－ＰＥ的ＬＯＩ（极限氧指数）又分别提高了２．４和６．５,达到２８．９和３０．９。研究了ＺＥＯ型号及用量对增效作用的影响。进一步利用ＴＧ（热重分析）和ＤＴＡ（差热分析）研究ＩＦＲ－ＰＥ的热降解行为,探讨了ＺＥＯ的增效作用原理。     

PLZT（28／0／100）薄膜的溶胶－凝胶制备技术及显微结构

用溶胶—凝胶技术及回旋法，在石英玻璃和单晶ｓｉ基片上制备ＰＬＺＴ（２８／０／１００）多晶薄膜；在ＳｒＴｉＯ３和α－Ａ１２Ｏ３单晶基片上外延生长择优取向薄膜．其外延关系分别为（１００）ＰＬＺＴ（２８／０／１００）／／（１００）ＳｒＴｉＯ３和（１００）ＰＬＺＴ（２８／０／１００）／／（０００１）Ａｌ２Ｏ３．用ＩＲ，ＸＲＤ．ＲＨＥＥＤ，ＳＥＭ和ＳＩＭＳ分析凝胶中杂质、凝胶的分子结构和薄膜的显微结构．结果表明，用溶胶—凝胶技术能制备出显微结构良好的多组份陶瓷薄膜．     

Pb（Mg1／2W1／2）O3—PbTiO3—PbZrO3l陶瓷的化学不均匀性和介电行为的…

研究了Ｐｂ（Ｍｇ１／２Ｗ１／２）Ｏ３－ＰｂＴｉＯ３－ＰｂＺｒＯ３陶瓷的化学不均匀性和介电行为。ＥＤＳ分析得到：体系中存在富Ｗ和富Ｚｒ、Ｔｉ的两相，平均分子式为：Ｉ相（富Ｗ相）：Ｐｂ（Ｍｇ０．２７０Ｗ０．３６７Ｚｒ０．１８２）Ｏ３．０９１；Ⅱ相（富Ｚｒ、Ｔｉ相）：Ｐｂ（Ｍｇ０．１０９Ｗ０．１８７Ｔｉ０．２０４Ｚｒ０．３４０）Ｏ２．７５８。两种居里点分别为：ＴＣＩ〈－６５℃，ＴＣＩ＝１０５℃，图像处理     

聚合物辐射裂解分维与其分子链的运动

从分维理论出发，讨论了聚合物在辐射交联反应中裂解度（Ｐ）与辐照剂量（Ｒ）间的关系。发现分维参数与聚合物内聚能密度密度（Ｅｃ）的表征分子链运动的参数分子链横截面积（Ａｐ）之间有一一对应的关系。建议用方程Ａｐ＝（１／Ｄ－０．４４）／０．００９Ｅｃ计算聚合物的Ａｐ值。用本方法计算出的Ａｐ值与文献值较一致。     

高分子p—n异质结太阳电池的研究

用合成的十二烷基苯磺酸（ＤＢＳＡ）掺杂的聚苯胺（ＰＡｎ）导电材料和Ｂｅｉ染料组合，采用涂覆技术，研制成ＳｎＯ２／ＰＡｎ膜／Ｂｅｉ染料薄层／Ａｌ栅电极结构和Ａｌ／ＰＡｎ导电基片／Ｂｅｉ染料薄层／Ａｌ栅电极结构的ｐ－ｎ异质结太阳电池，测定了该电池的光电效应和伏安特性，在４．７２ｍＷ／ｃｍ＾２的氙灯照射下，开路电压Ｖｏｃ达４００ｍＶ短路电流Ｉｓｃ为１０μＡ，填充因子可达５７．４％，光电转换效率为０．０９     

HDPE／顺丁橡胶共混材料磨蚀速率的研究

用自制的旋臂式磨蚀实验仪，研究了高密度聚乙烯（ＨＤＰＥ）／顺丁橡胶、高密度聚乙烯和４５＾＃钢在攀枝花尾矿矿浆中的磨蚀速率与磨蚀温度和磨蚀时间的关系。结果表明，在２０－４８℃时，Ｗ（ＨＤＰＥ／ｃｉｓ－ＢＲ）和Ｗ（ＨＤＰＥ）分别保持在０．１７－０．２０ｍｍ／ａ和０．２２－０．３０ｍｍ／ａ。在５５℃时，Ｗ（ＨＤＰＥ／ｃｉｓ－ＢＲ和Ｗ（ＨＤＰＥ）分别增加至０．２８和０．３９ｍｍ／ａ，在２０－５５℃时，Ｗ（     

双环戊二烯聚合反应热力学和动力学研究

研究了ＤＣＰＤ－ＷＯＣｌ４－ＡｌＥｔ３体系前阶段的反应动力学，采用ＧＣ法分析了不同反应条件下的动力学数据，发现ｌｇ（［ＤＣＰＤ］０／［ＤＣＰＤ］）￣ｔ存在线性关系，说明该体系在前段的聚合反应为一链式反应符合二级反应模型。同时还对该体系聚合反应热力学也进行了研究；对聚合反应的ΔＨｐ、ΔＳｐ、ΔＧｐ进行了讨论。     

Pd在SnO2薄膜上的淀积、扩散及对气敏性能的影响

在Ａｒ气氛中于ＳｎＯ２薄膜表面溅射一层很薄的金属钯。用ＳＥＭ、ＡＥＳ及ＸＰＳ等分析表明，Ｐｄ在ＳｎＯ２表面以三维束状小岛方式生长，热处理后Ｐｄ迅速扩散到ＳｎＯ２膜内，形成掺杂型的气敏元件。在元件的表面存在大量的化学吸附氧，低温下（～１６０℃）对极为稳定的ＣＨ４有很高的灵敏度，认为可能与低温下吸附氧主要为α氧（Ｏ－２）有关。     

Time resolved luminescence of quartz from Nigeria

Characteristics of luminescence lifetimes and luminescence intensity obtained from time resolved spectra of quartz from Nigeria are presented. The luminescence was pulse-stimulated at 11 μs width at 470 nm. Samples used consisted of unannealed quartz as well as samples annealed at 500 °C, 600 °C, 700 °C, 800 °C and 900 °C. The luminescence lifetimes and luminescence intensities were studied as a function of annealing temperature, irradiation dose and measurement temperature. It was found that there is a decrease, although non-monotonic, in the luminescence lifetime with change in annealing temperature from 20 to 900 °C. In addition, lifetimes extracted from time resolved spectra of unannealed samples as well as ones annealed at 500 °C and 600 °C are initially independent of irradiation dose but do later decrease with further irradiation. Regarding the luminescence intensity it was observed that in general, the intensity passes through a peak as the measurement temperature is increased from 20 to 200 °C with slight differences in the detailed pattern dependent on preheating. Activation energies for thermal quenching and thermal assistance evaluated from temperature-dependent changes of luminescence lifetime and luminescence intensity are given. The results are discussed in terms of a model consisting of three luminescence centres with probability of hole trapping during irradiation being highest for the luminescence centre associated with the least lifetime.     

Upconversion luminescence properties of YF3:Yb3+, Er3+ nanoclusters

The synthesis, characterization, and spectroscopy of upconverting Yb3+/Er3+ codoped YF3 rod-like nanoclusters are presented. The YF3 nanoclusters were synthesized by a simple hydrothermal method. The clusters structure was characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Under 978 nm laser excitation, stronger blue (4F(5/2) --> 4I(15/2) and 2p(3/2) --> 4I(11/2)) and green (4S(3/2), 2H(11/2) --> 4I(15/2)) upconversion luminescence were observed at 978 nm. The measured intensity of upconversion luminescence was different when pump power changed, which shows that the blue and green upconversion luminescence come from three-photon and two-photon energy transfer processes, respectively.     

The N3 center luminescence quenched by nitrogen impurity in natural diamond

N3 center luminescence quenching by the main types of defects (A and B1) related to nitrogen impurity in natural diamond was studied by monitoring the luminescence yield and using the Raman scattering intensity as a measure of the exciting radiation intensity. The luminescence yield from the N3 centers decreases by a factor of about 3000 when the concentration of nitrogen in the form of type A and B1 defects in natural diamond increases from 0.008 to 0.1 at. %.     

Pressure effects in differential mobility spectrometry

A microfabricated planar differential ion mobility spectrometer operating from 0.4 to 1.55 atm in a supporting atmosphere of purified air was used to characterize the effects of pressure and electric field strength on compensation voltage, ion transmission, peak width, and peak intensity in differential mobility spectra. Peak positions, in compensation voltage as a function of separating rf voltage, were found to vary with pressure in a way that can be simplified by expressing both compensation and separation fields in Townsend units for E/N. The separation voltage providing the greatest compensation voltage and the greatest resolution is ion-specific but often occurs at E/N values that are unreachable at elevated pressure because of electrical breakdown. The pressure dependence of air breakdown voltage near 1 atm is sublinear, allowing higher E/N values to be reached at reduced pressure, usually resulting in greater instrumental resolution. Lower voltage requirements at reduced pressure also reduce device power consumption.     

The time-resolved luminescence characteristics of Ce and Ce/Pr doped YAG ceramics obtained by high pressure technique

Transparent Ce and Ce/Pr doped YAG ceramics were prepared under high pressures (up to 8 GPa) and relative low temperature (450 °C). Grain size of the ceramics is less than 50 nm. However unknown defects or disorders strains on grain boundaries caused the additional absorption in these ceramics. The luminescence intensity, spectra and the decay time dependence on pressure applied during ceramic preparation were studied. Concentration of some intrinsic point defect was reduced under the high pressure applied for sintering process.It is shown that formation time of the excited state of Ce luminescence depends on the pressure applied during ceramic sintering.     

Erbium ion implantation into different crystallographic cuts of lithium niobate

Single crystals like lithium niobate are frequently doped with optically active rare-earth or transition-metal ions for a variety of applications in optical devices such as solid-state lasers, amplifiers or sensors. To exploit the potential of the Er:LiNbO₃, one must ensure high intensity of the 1.5 μm luminescence as an inevitable prerequisite. One of the important factors influencing the luminescence properties of a lasing ion is the crystal field of the surrounding, which is inevitably determined by the crystal structure of the pertinent material. From that point it is clear that it cannot be easy to affect the resulting luminescence properties - intensity or position of the luminescence band - without changing the structure of the substrate. However, there is a possibility to utilise a potential of the ion implantation of the lasing ions, optionally accompanied with a sensitising one, that can, besides the doping, also modify the structure of the treated area od the crystal. This effect can be eventually enhanced by a post-implantation annealing that may help to recover the damaged structure and hence to improve the desired luminescence.In this paper we are going to report on our experiments with ion-implantation technique followed with subsequent annealing could be a useful way to influence the crystal field of LN. Optically active Er:LiNbO₃ layers were fabricated by medium energy implantation under various experimental conditions. The Er⁺ ions were implanted at energies of 330 and 500 keV with fluences ranging from 1.0 × 10¹⁵ to 1.0 × 10¹⁶ ion cm⁻² into LiNbO₃ single-crystal cuts of both common and special orientations. The as-implanted samples were annealed in air and oxygen at two different temperatures (350 and 600 °C) for 5 h. The depth concentration profiles of the implanted erbium were measured by Rutherford Backscattering Spectroscopy (RBS) using 2 MeV He⁺ ions. The photoluminescence spectra of the samples were measured to determine the emission of 1.5 μm.It has been shown that the projected range Rp of the implanted erbium depends on the beam energies of implantation. The concentration of the implanted erbium corresponds well with the fluence and is similar in all of the cuts of lithium niobate used. What was different were the intensities of the 1.5 μm luminescence bands not only before and after the annealing but also in various types of the crystal cuts. The cut perpendicular to the cleavage plane 〈10-14〉 exhibited the best luminescence properties for all of the experimental conditions used. In order to study the damage introduced by the implantation process, the influence of the annealing procedure on the recovery of the host lattice was examined by RBS/channelling. The RBS/channelling method serves to determine the disorder density in the as-implanted surface layer.     

Luminescence properties of ZnS:Mn nanocrystals embedded in SiO2 by ion implantation

Sequential multi-energy implantations of zinc and sulphur ions have been performed in a 250-nm thick SiO₂ layer thermally grown on 1 1 1 silicon. Energies and doses have been chosen to produce 10 at.% constant concentration profiles overlapping over about 100 nm. Manganese is subsequently introduced at various levels by the same way. Thermal treatments (from 700 to 1100 °C) lead to the formation of nanometric precipitates of the luminescent compound ZnS:Mn. A bimodal size distribution is observed, with a quasi-single layer of large particles (40 nm) in the end-of-range region and much smaller precipitates between this layer and the surface. The orange emission is maximal when the Mn concentration is close to 3%. Several hours at 900 °C is the best thermal budget for maximal luminescence intensity at room temperature. A shift of the excitation spectrum related to size variations, shows that the particles of smaller size are mainly responsible for the observed luminescence. In agreement with other authors, the luminescence lifetime is found in the ms range and increases with the nanocrystal diameter, tending to the lifetime of bulk ZnS. The luminescence of ZnS:Mn nanoparticles embedded in SiO₂ by ion implantation is also shown to be very stable during long UV light irradiation.     

Ba5Zn4Y8O21:Ho^3+,Yb^3+上转换发光粉的制备与发光性能研究

为实现以Ba5Zn4Y8O21为基质的上转换三基色发光,采用固相合成法于1200℃下制备了Ba5Zn4Y8O21:Ho^3+,Yb^3+发光粉,并对其绿光发射特性进行了研究。980 nm激发下的上转换发射光谱测试结果证实,最佳掺杂浓度下的Ba5Zn4Y8O21:14%Yb^3+,0.15%Ho^3+主要呈现5S2/5F4→5I8跃迁所致的548、553 nm绿光发射,而5F5→5I8和5S2/5F4→5I7跃迁产生的664、758nm红光和近红外光发射非常微弱。而且,绿光强度随激发功率呈线性变化,在20.7 mW/cm^2功率密度范围内,绿红光分支比最高达13.16,呈现优异的色纯度。上转换发光热稳定性测试结果表明,样品的发光效率随样品温度的升高略有下降,50℃时发光强度降低仅9.75%。上述结果证实,Ba5Zn4Y8O21:Ho^3+,Yb^3+是一种优质的绿光上转换发光材料。     

HOLOGRAPHIC STUDY OF FATIGUE DEFORMATION AND CRACK GROWTH IN METALS

Abstract— Changes in optical correlation intensity ( I _c) are observed during fatigue cycling of 2024-T3 aluminum alloy. Topographic changes such as slip band development, microcracking, and crack propagation, observed in situ during fatigue cycling cause corresponding changes in correlation intensity. A three-stage curve of log ( I _c) vs number of fatigue cycles is observed. Metallographic observations show that region A corresponds to progressive roughening of the specimen surface caused by slip together with a rapid increase in the number of microcracks up to about 10 μm in length. Few metallographic changes are observed during region B where the correlation intensity remains relatively constant. The metallographic observations show that the accelerating loss of correlation intensity during region C is caused by propagation of cracks more than about 10 μm in length. The loss in correlation intensity during region C arises from the elastic and plastic displacements which occur as the crack length increases. At the present sensitivity of the experiments, crack growth to a length of a few hundred microns causes correlation intensity losses as great as four orders of magnitude or more. The correlation intensity readings during region C are sensitive to factors such as crack branching and crack-tip plasticity as well as to the overall increase in crack length. The total loss in correlation intensity from the beginning of a test to a crack length of about 800 μm can be more than eight orders of magnitude. The optical correlation technique is an extremely sensitive method of detecting remotely, in air, both deformation and fatigue crack growth.     

Fluorescent imaging of pH with optical sensors using time domain dual lifetime referencing

We present a referenced scheme for fluorescence intensity measurements that is useful for imaging applications. It is based on the conversion of the fluorescence intensity information into a time-dependent parameter. A phosphorescent dye is added in the form of approximately 10-microm particles to the sample containing the pH-sensitive fluorescent indicator. Both the reference dye and the pH probe are excited simultaneously by a blue LED, and an overall luminescence is measured. In the time-resolved imaging method presented here, two images taken at different time gates were recorded using a CCD camera. The first image is recorded during excitation and reflects the luminescence signal of both the fluorophore (pH) and the phosphor (reference). The second image, which is measured after a certain delay (after switching off the light source), is solely caused by the long-lived phosphorescent dye. Because the intensity of the fluorophore contains the information on pH, whereas phosphorescence is pH-independent, the ratio of the images displays a referenced intensity distribution that reflects the pH at each picture element (pixel). The scheme is useful for LED light sources and CCD cameras that can be gated with square pulses in the microsecond range. The fundamentals and potential of this new method, to which we refer as time domain dual lifetime referencing (t-DLR), are demonstrated.