Laser-Induced Molecular Plasma: A Medium for High-Order Harmonics Generation of Ultrashort Pulses

I present a study of laser-induced plasmas (LIPs) produced on the surfaces of molecular targets to create optimal conditions for high-order harmonics generation during the propagation of femtosecond pulses through the LIP. The resonance enhancement of a harmonic, two-color pump of plasma, quasi-phase-matching and nanoparticle-induced growth of the harmonic yield are analyzed, which allows for the formation of sources of coherent extreme ultraviolet radiation based on molecular plasma formation.     

Synthesis of Ferroelectric Lead Titanate Nanohoneycomb Arrays via Lead Supplement Process

Here, we demonstrate a novel process to convert TiO₂ nanotubes into ferroelectric nanohoneycombs, comprised of vertically aligned PbTiO₃ nanotubes. Tube bottom opening process enabled effective infiltration of lead acetate precursor into the nanotubes. Nanohoneycombs, which were converted via additional lead supplement process, showed uniform conversion and well‐defined ferroelectric properties with the effective piezoelectric coefficient of approximately 20 pm/V, which was measured by piezoresponse force microscopy.     

Lead Zirconate Titanate Thin Films on Base-Metal Foils: An Approach for Embedded High-Permittivity Passive Components

An approach for embedding high-permittivity dielectric thin films into glass epoxy laminate packages has been developed. Lead lanthanum zirconate titanate (Pb_0.85La_0.15(Zr_0.52Ti_0.48)_0.96O₃, PLZT) thin films were prepared using chemical solution deposition on nickel-coated copper foils that were 50 μm thick. Sputter-deposited nickel top electrodes completed the all-base-metal capacitor stack. After high-temperature nitrogen-gas crystallization anneals, the PLZT composition showed no signs of reduction, whereas the base-metal foils remained flexible. The capacitance density was 300–400 nF/cm², and the loss tangent was 0.01–0.02 over a frequency range of 1–1000 kHz. These properties represent a potential improvement of 2–3 orders of magnitude over currently available embedded capacitor technologies for polymeric packages.     

氢化物发生-原子荧光法测定茶叶中的铅

建立了测定茶叶中微量铅的氢化物发生 -原子荧光光谱方法 ,方法灵敏度高 ,准确度好。在选定的实验条件下 ,荧光强度与铅浓度在 0～ 2 80 μg/L范围内呈线性关系 ,相关系数 0 .9996 ,检出限为 0 .2 6 μg/L,回收率 91 .6 %～ 98.7%,相对标准偏差不超过 5 .2 %。     

Microwave Effects in Lead Zirconium Titanate Synthesis: Enhanced Kinetics and Changed Mechanisms

A novel, simple, and fast solid-state procedure has been demonstrated for the synthesis of Pb(Zr,Ti)O₃ (PZT), using microwave radiation. The process consists of starting with the respective oxides mixed in the required proportions and exposing the charge to the microwaves. By making one or more of the constituent oxides slightly nonstoichiometric, enormous enhancement in reaction rates has been achieved, and single-phase PZT can be synthesized at temperatures as low as 600°C. Moreover, it has been shown that the combined use of nonstoichiometric precursors and microwave irradiation leads to different reaction pathways for the formation of PZT. Further, the microwave method diminishes PbO loss.     

银杏叶中有效铅的测定

采用氢化物发生-原子荧光法测定了银杏叶中的有效铅,考察了仪器的工作条件、酸介质浓度、载流浓度、硼氢化钾浓度等对原子荧光强度的影响。实验结果表明,银杏叶中有效铅的含量水平在0～0.002mg/L之间,加标回收率为87.50%～93.75%。     

氢化物发生—原子荧光光度法测定面粉中微量铅

建立了测定面粉中微量铅的氢化物发生-原子荧光光度法。在实验条件下,铅的线性范围为0~40 ng/m L,测定精密度为1.9%,检出限为0.029 ng/m L,样品加标回收率在94.5%~102%之间。该方法简单、快速、灵敏度高、重现性好。     

检测化妆品中铅的新方法研究

研究了二溴对甲虫基偶氮甲磺（ＤＢＭ－ＭＳＡ）与铅的显色反应,在０．２４ｍｏｌ／ＬＨ３ＰＯ４介质中,铅与ＤＢＭ－ＭＳＡ发生灵敏的显色反应,生成稳定的蓝色配合物。其组成比为Ｐｂ（Ⅱ）;ＤＢＭ－ＭＳＡ＝１：２,最大吸收波长在６４２ｎｍ,表观ｍｏｌ吸光系数达０．５４×１０＾４,铅的浓度在０μｇ／２５ｍＬ￣１５μｇ／２５ｍＬ服从比耳定律,可以允许大量的金属离子（除钙外）共存。进一步研究发现,结合ＫＩ－ＭＩＢ     

Hydrothermal Synthesis of Acicular Lead Titanate Fine Powders

A pure, acicular lead titanate (PbTiO₃) fine powder with a white color has been prepared by hydrothermal synthesis. It is a new phase of PbTiO₃ with I 4 symmetry, cell parameters of a = 12.358 Å and b = 14.541 Å, and a density of 6.80 g.cm⁻³. The influences of pH (12.5 to 14.4), Pb/Ti ratio (1.0 to 1.6) in the feedstock, reaction temperature (130° to 230°C), time (0.25 to 4 h), starting materials, and additives on the formation of acicular PbTiO₃ under hydrothermal conditions have been investigated. The acicular PbTiO₃ with I 4 symmetry, referred to as the PX phase, can be converted to the perovskite-type (PE phase) of PbTiO₃ at about 605°C while its acicular morphology is essentially unchanged. The preferable conditions for preparing pure acicular PX-phase PbTiO₃ are that the pH is 13.0 to 14.0, Pb/Ti ratio is >1.3, reaction temperature is 170° to 200°C, time is 0.5 to 1.0 h, titanium butoxide (Ti[O(CH₂)₃CH₃]₄) is the starting material, and poly(vinyl alcohol) is an additive. The acicular grain of the PX phase is usually less than 100 nm in diameter and more than 1000 nm in length.     

均匀沉淀法合成超细碳酸铅

采用均匀沉淀法合成碳酸铅，研究反应温度、时间、反应物浓度、反应物配比对碳酸铅收率的影响。运用TEM对合成的碳酸铅形态及颗粒尺寸大小进行表征。通过实验确定了解制备碳酸铅的最佳工艺条件：反应温度为95℃，反应时间为5h，反应物浓度为0．5mol/l，反应物配比为1：6。TEM图像表明，制备的碳酸铅为斜方晶体，料径为1－15μm，实验结果表明：采用均匀沉淀法可以制备料径小，分散均匀的越细碳酸铅。     

变压吸附(PSA)空分制氧技术进展

论述了 PSA法空分制氧分子筛的开发现状和制氧工艺的进展 ,为 PSA法空分制氧今后的发展提出了研究方向     

Electrochemical Fingerprint of Archeological Lead Silicate Glasses Using the Voltammetry of Microparticles Approach

The application of a solid‐state electrochemical technique, voltammetry of microparticles (VMP), for studying archeological lead glass is described. Upon attachment to graphite electrodes immersed into aqueous acetate buffer, characteristic voltammetric profiles were obtained for submicrosamples of archeological glasses dated between the 9th and 19th centuries. Bivariate and multivariate chemometric analyses of the VMP data allowed us to characterize individual workshops/provenances which enabled a clear discrimination between soda‐rich and potash‐rich glasses. An analysis of the VMP data, combined by XRF, FESEM, AFM and ATR‐FTIR and Micro‐Raman spectroscopies, denoted the presence of Pb(IV) centers accompanying network‐former and network‐modifier Pb(II).     

Total Synthesis of Symbioramide: a Flexible Approach for the Efficient Preparation of Structural Isomers

A concise, enantioselective total synthesis of symbioramide, starting from simple achiral compounds and racemic α‐amino‐β‐keto ester derivatives is reported. This highly flexible strategy allowed the efficient preparation of seven structural isomers of the natural product as well. The synthesis relies on a convergent route that involves the efficient stereoselective reduction of a α‐keto‐β‐yne ester, and the dynamic kinetic resolution of an α‐amino‐β‐keto ester through ruthenium‐mediated asymmetric hydrogenation.     

氢化物发生-原子荧光法测定化学试剂中铅砷

建立了一套应用氢化物发生-原子荧光法测定化学试剂中铅、砷含量的方法.对液体类型化学试剂(如HCl、H2SO4、HNO3等)和固体类型化学试剂(如NaOH、K2Cr2O,、KMnO4等)分别采用氧化还原、酸碱处理等方法进行处理,建立了样品的前处理方法.研究了测定样品中铅、砷的合理曲线拟合范围,仪器灯电流、负高压、载气流量、屏蔽气流量与荧光强度的相关性,共存背景物质的干扰情况,以及测定过程中酸的种类及酸度大小对试验结果的影响.结果表明,此方法简便、快速、准确.测定铅、砷的线性范围分别在0～40ug/L和0～40ug/L,相关系数分别为0.9999和0.9998.相对偏差小于1.0%,加标回收率分别为99.18%、100.78%.     

Synthesis of Lead Nickel Niobate–Lead Zirconate Titanate Solid Solutions by a B-site Precursor Method

A modified processing method for lead nickel niobate–lead zirconate titanate (Pb(Ni_1/3Nb_2/3)O₃–Pb(Zr,Ti)O₃, PNN–PZT) solid solutions is presented. This method is based on the high-temperature synthesis of a precursor that contains all the B-site cations (Ti, Zr, Ni, and Nb). This synthesis yields a diphasic mixture that contains a ZrTiO₄-like phase and a rutile-like phase. Both phases exhibit a cationic valence of 4; thus, it is concluded that the mixing of Ni and Nb cations is adequate for the preparation of PNN–PZT solid solutions. Indeed, a pure perovskite phase has been obtained after calcination with lead oxide for compositions that contain 40 and 50 mol% PNN. Moreover, their electromechanical properties have been shown to be superior to values reported for standard columbite routes. This conclusion has been interpreted in terms of enhanced chemical homogeneity.     

光纤反射型传感器用于水中铅的测定

研究了一种将二甲酚橙固定在上海717阴离子交换树脂上作为试剂相的光导纤维反射型传感器。铅离子与固定在阴离子交换树脂上的二甲酚橙的络合反应，使试剂相光反射强度发生了很大的变化，从而使溶液中的铅离子得以测定。传感器具有较高的灵敏度和良好的选择性，已成功用于水中铅的检测。     

Poling of Lead Zirconate Titanate Ceramics and Flexible Piezoelectric Composites by the Corona Discharge Technique

In the conventional poling method, piezoelectric ceramics and composites are poled by applying a large dc voltage. Poling of composites having a polymer matrix with 0–3 connectivity is especially difficult because the electric field within the high-dielectricconstant grains is far smaller than in the low-dielectric-constant polymer matrix. Therefore, very large electric fields are required to pole these types of composites. However, large electric fields often cause dielectric breakdown of the samples. In this study for improved poling, the corona discharge technique was used to pole piezoelectric ceramics, fired PZT composites, and 0.5PbTiO₃· 0.5BiFeO₃ 0–3 polymer composites. An experimental setup for corona poling is described. The dielectric and piezoelectric properties of materials poled by the corona discharge technique were comparable to those obtained with the conventional poling method.     

聚丙烯酰胺-钠基复合膨润土合成及其吸附铅离子性能

以丙烯酰胺为聚合单体,钙基膨润土为主要原料,采用钠化改性及水溶液聚合连续工艺合成了系列复合膨润土,对其进行了表征,并考察了丙烯酰胺的溶出量和对Pb2+的吸附性能. 结果表明,丙烯酰胺在膨润土层间发生了插层聚合,复合膨润土为片层结构,稳定性较好. 复合膨润土对Pb2+的吸附量高于粉末膨润土和钙基复合膨润土,且吸附量随膨润土含量增加而增加,膨润土含量为90%的钠基复合膨润土对Pb2+的吸附量可达118.35 mg/g,吸附符合Lagergren二级动力学模型.     

Novel Synthesis Route to Make Nanocrystalline Lead Zirconate Titanate Powder

The present research describes synthesis of perovskite lead zirconate titanate (PZT) nanocrystalline mesoporous powders from the aqueous solutions of Pb²⁺, Zr⁴⁺, and Ti⁴⁺ metal ions using sucrose as a template material. Sucrose retains the metal ions in solution through complex formation. Dehydration and thermal decomposition of the metal ion–sucrose mass produces a large amount of gas, which helps to create porosity and high surface area in the final products. The particle size of the synthesized powder is between 50 and 60 nm, with a average specific surface area between 20 and 25 m²/g. The surface area increases as the amount of sucrose increases. Nanocrystalline PZT powder with high surface area can be useful for low-temperature sintering.     

二乙醇胺辅助溶胶-凝胶法低温合成锆钛酸铅纳米粉体

以醋酸铅[Pb（CH3COO）2^-33H20]、硝酸锆[Zr（N03）4^-5H2O]和钛酸四丁酯[Ti（C4H90）4]为原料,以二乙醇胺（diethanolamine,DEA）为聚合剂．用溶胶-凝胶法制备了锆钛酸铅（PbZrxTil-x03,PZT）纳米陶瓷粉体。研究了DEA对溶胶-凝胶法合成PZT陶瓷粉体的影响...