Ultranarrow bandwidth tunable atomic filter via quantum interference-induced polarization rotation in Rb vapor

We report the experimental demonstration of an ultranarrow bandwidth atomic filter by optically induced polarization rotation in multilevel electromagnetically induced transparency systems in hot Rb vapor. With a coupling intensity of 2.3 W/cm^2, the filter shows a peak transmission of 33.2% and a bandwidth of 10 MHz. By altering the coupling frequency, a broad tuning range of several Doppler linewidths of the D1 line transitions of STRb atoms can be obtained. The presented atomic filter has useful features of ultranarrow bandwidth, and the operating frequency can be tuned resonance with the atomic transition. Such narrowband tunable atomic filter can be used as an efficient noise rejection tool in classical and quantum optical applications.     

Synthesis and Characterization of Ordered Mesoporous Aluminosilicate Molecular Sieves with High Stability in High-Temperature Steam

The ordered mesoporous aluminosilicate molecular sieve （MASMS-1） stable in the high-temperature steam has been successfully synthesized from the assembly of diluted ZSM-5-type precursor with mesoporous MCM-41. The material was characterized by XRD, N2 adsorption-desorption, FE-SEM, TEM, FT-IR spectroscopy and 27A1 MAS NMR techniques. This mesoporous material shows high stability in the high-temperature steam [H2O （φ=20%） in N2 at 800 ℃ for 4 h], which might be ascribed to the synergistic effect of both thick walls containing zeolite-like five-membered ring subunits and highly condensed surface silanol groups.     

“蒸汽相转化”法制备纳米晶组成的块状方钠石多级孔沸石催化材料

将实验室合成的聚苯乙烯乳胶微球(PS)加入制备方钠石(SOD)沸石的前驱体凝胶中,在45℃条件下制得干凝胶,随后采用"蒸汽相转化"法制备了大块状SOD沸石材料。对影响多级SOD沸石形成因素进行了详细讨论。采用X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、N_2吸附-脱附和压汞技术等表征手段对制备的材料进行了详细表征。结果表明通过"蒸汽相转化"法制备的大块状SOD沸石由球状多晶聚集体构成,这些球状多晶聚集体又是由粒径为50~100 nm的初级纳米晶粒组成,在初级纳米晶粒上和纳米晶粒之间形成了2~50 nm介孔结构以及由脱除PS微球形成的50~300 nm的大孔结构。     

板栗真空爆壳机水蒸汽喷射式真空系统的设计

根据板栗真空爆壳工艺试验的研究及爆壳机对真空系统的工作要求,设计了水蒸汽喷射真空泵附设启动喷射泵的真空系统,并将喷射器泛汽用于爆壳过程的加热,使真空爆壳机具有运行稳定可靠,高效低耗等特点.     

量子点复合物发光二极管发射红外光

以悬浮在半导体聚合物中的量子点为特征的电致发光合成物．可望使应用于通信的高级光源易于发展。多伦多大学发展的一种发光二极管原型能在通信波长产生近红外辐射,其发射强度依据量子点的大小而不同。     

蒸汽相转化法原位诱导沸石化制备Y-ZSM-5双沸石复合物

针对Y型沸石在ZSM-5沸石干胶制备及晶化过程中易于溶解、坍塌的问题,采用葡萄糖在水热处理条件下对Y沸石进行包膜处理,提高了Y沸石在高温、高碱度环境中的稳定性,并采用蒸汽相转化法制备了同时含有Y和ZSM-5的双沸石复合物。对影响沸石复合物形成的因素如Y沸石表面碳包膜改性、凝胶碱度、晶化时间等进行了详细讨论。采用X射线衍射(XRD)、扫描电子显微镜(SEM)、傅立叶变换红外(FT-IR)、N2吸附-脱附,能谱(EDS)以及NH3-TPD等手段对制备的材料进行了表征。结果表明通过蒸汽相转化法能获得Y和ZSM-5两相共存的双沸石复合物,产物中的ZSM-5沸石相前驱体随蒸汽处理时间的延长逐渐从蠕虫状无定型向纳米多晶ZSM-5沸石转变,纳米多晶聚集体与Y型沸石晶粒之间紧密相连,相互包埋。在异丙苯催化裂化反应中,合成的沸石复合物的活性和稳定性介于Y和ZSM-5之间,优于对应的机械混合物。     

基于熔融盐加热的SMR膜反应器热力学优化

建立了基于熔融盐加热的甲烷蒸汽重整膜反应器(MS-SMRMR)模型,以甲烷转化率最大、氢气产率最大和总熵产率最小为优化目标,利用带精英策略的非劣解排序遗传(NSGA-Ⅱ)算法对MS-SMRMR进行了三目标优化。研究结果表明:Pareto最优前沿包含了各单目标优化的最优解;利用TOPSIS方法在Pareto最优前沿上选择得到了最优的决策点,该决策点所对应的甲烷转化率、氢气产率和总熵产生率与参考点的结果相比分别提高了8.4%,8.5%和4.32%。     

基于IAPWS-IF97的水与蒸汽性质计算的反推算法

在IAPWS发布的反推公式补充模型的基础上,以温度和比焓计算压强为例,对工程实施时的相关算法设计进行了改进,提出对边界进行准确界定的＂逆向验证法＂,提高了计算的准确性。     

Vapor Sensing Theoretical Study on Optical Microcavities

When the organic vapors absorbed to the surface of porous silicon（PS）, capillary condensation takes place due to the porous structure of the PS layer, accordingly resulting in the effective refractive index changing. For PS multi-layer microcavities, the different resonant peaks shift in the reflectivity spectrum of porous silicon microcavities（PSMs）. The optical sensing model is set up by applying Bruggeman effective medium approximation theory, capillary condensation process and transfer matrix theoretically analytical method of one-dimensional photonic crystals. At the same time, comprehensively researched on are the sensing characteristics of PSMs which are exposed to give concentration organic vapors. At last, made is the theoretical simulation for sensing model of the PSMs in case of saturation by using computer numerical calculation, and found is the linearity relation between the refractive index of organic solvent and the peak- shift. At the same time deduced is the peak-shift as a function of the concentration of ethanol vapors.     

火电厂余热用于海水淡化的工艺浅析

随着我国人口不断增长和经济的飞速发展,淡水资源匮乏的形势日趋严重。海水淡化作为一种开辟新水源的新技术,已经成为世界上公认的解决淡水短缺问题的最佳方案。由于海水淡化成本在很大程度上取决于消耗电力和蒸汽的成本,而沿海地区火电厂低品位的蒸汽较多,如汽轮机做过功的蒸汽,各种废热等等,往往因品味太低无法充分利用,若直接排入大气则会造成极大的浪费,甚至会污染环境。利用火电厂无法利用的废热蒸汽作为动力蒸汽,采用低温多效蒸馏的海水淡化工艺,实施水电联产,即能充分发挥火电厂的优势,又能实现节能环保这一终极工业目标,同时丰富了可贵的淡水资源。