Enhancement of SrTiO<Subscript>3</Subscript>/BiPO<Subscript>4</Subscript> heterostructure for simulated organic wastewater degradation under UV light irradiation

A novel SrTiO₃/BiPO₄ heterostructure with different amounts of SrTiO₃ have been successfully prepared through the hydrothermal process. The photocatalysts were characterized by X-ray powder diffraction, UV–Vis diffuse reflectance spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The photocatalytic performance was evaluated by degrading the methylene blue dye solution under UV light. Results showed that the samples displayed excellent photocatalytic degradation efficiency due to the highly efficient suppression of the recombination of electron–hole pairs. A possible mechanism of SrTiO₃/BiPO₄ heterojunctions was discussed. The research indicated that the as-prepared SrTiO₃/BiPO₄ heterogeneous photocatalyst can be used as an effective material for degrading industrial organic wastewater.     

Synthesis,structures and magnetic properties of two 2D → 3D entangled Cobalt(II) coordination polymers

Two Co(II) coordination polymers, namely Co(HBTC)(4-bpdb)·H₂O (1) and Co(HBTC)(3-bpdb)·H₂O (2) (H₃BTC = 1,3,5-benzenetricarboxylic acid, 4-bpdb = 1,4-bis-(4-pyridyl)-2,3-diaza-1,3-butadiene, 3-bpdb = 1,4-bis(3-pyridyl)-2,3-diaza-1,3- butadiene), have been hydrothermally synthesized and characterized both structurally and magnetically. Compound 1 exhibits a (2D → 3D) polythreaded architecture. It is assembled from HBTC^2? ligands to form a 2D puckered (4,4) layer plus 4-bpdb ligands which are orientated above and below each layer. The structure of compound 2 consists of a 2D (3,5) wavelike sheet constructed from HBTC^2? anions and 3-bpdb spacers. The uncoordinated carboxyl groups of the HBTC^2? ligands protrude from both sides of the wavelike sheet to form a 2D → 3D interdigitated motif. The magnetic properties of both compounds are also investigated, indicating antiferromagnetic interactions between the adjacent metal centers.     

Encapsulation of RNA by negatively charged human serum albumin via physical interactions

Human serum albumin (HSA) is the most abundant plasma protein and has an inherent ability to target tumor cells. It is an excellent candidate for drug delivery. However, HSA cannot form complex with DNA or RNA, because it is negatively charged under physiological conditions. In this work, we reported a simple method to prepare HSA/RNA nanoparticles mainly by physical interaction. Firstly, the solution pH is adjusted to 4.0, under which condition HSA is positively charged. It forms complex with RNA via electrostatic interaction. The solution is then heated at 75 oC for 15 min to stabilize the structure and the size of the formed complex. The HSA/RNA nanoparticle prepared by this method has a diameter about 110 nm and a narrow distribution. It is also stable for days under physiological conditions. Cellular essays demonstrate that these particles exhibit a high cellular uptake efficiency and non-toxicity to HeLa cells.     

PBT／PC共混体系流变性能与形态结构研究

采用毛细管流交仪测定了ＰＢＴ／ＰＣ共混物的表观粘度、剪切应力，观察了不同共混物组成和不同温度下共混物的流变行为，并借助扫描电镜对共混物和微观形态结构进行分析。结果表明：ＰＢＴ／ＰＣ熔体共混物的流变行为接近假塑性流体．温度对共混物的流变行为影响很大，共混物的熔体粘度在ＰＢＴ／ＰＣ为９０／１０和６０／４０时呈双极值．共混物为两相结构，ＰＣ含量为４－５０％时呈两互锁结构。     

甲氟哌酸的极谱伏安行为研究及其应用

本较详细研究了甲氟哌酸的极谱伏安行为。在０．０２ｍｏｌ／Ｌ氯化铵底液中，甲氟哌酸产生一个良好的还原峰，峰电位（Ｅｐ）为－１．４５０Ｖ。其导数峰高与浓度在９×１０＾－５－３×１０＾－７ｍｏｌ／Ｌ范围内呈现良好的线性关系，大多数金属离子和无机阴离子不干扰测定，用于甲氟哌酸合杨样品的测定，结果满意。本还用多种电化学方法和技术研究了还原峰电流的性质，并提出了电极反应的机理。     

甲基丙烯酸C_7～C_9酯的基闭转移聚合

研究了甲基丙烯酸Ｃ_７～Ｃ_９酯的基团转移聚合。聚合必须在８０℃以上进行，讨论了聚合条件对聚合速率、分子量、分散性及转化率的影响。     

微量元素与中医辩证分型

通过对两间小学639名学生进行微量元素检测及体格检查，并进行中医辩证分型，发现广州市部份小学生体内微量元素缺乏较严重，占体检总人数的62．3％，同时也存在营养不良，贫血、佝偻病，急慢性上呼吸道炎等、按中医辩证分型有肝热、脾气虚弱、肝血不足、肾气虚等，本文试从微量元素缺乏与中医辩证中找出两者之间的联系，以便于指导治疗，提高小学生的健康水平，增强体质和智力。     

Exposure dose assessment and discussion on radioisotope production and application

The exposure dose status on radioisotope production and application in China has been assessed in the paper. The average annual occupational exposure dose received by workers in the radioisotope production is about one tenth of the annual dose limit in normal situation. It is less than one twentieth for workers in the radioisotope applications. However, the annual collective dose for the latter is higher than the former by one oder of magnitude due to the larger number of workers in the application field. Although the output of radioisotopes increased doubly in 1980's as compared with 1970's, the increase on the annual collective dose was not obvious. For exposure to the public,¹³¹I for example, the collective dose in the radioisotope production decreased by one to two orders of magnitude and the releasing factor reduced by two orders of magnitude. Therefore, the exposure dose received by workers in radioisotope production and application is lower in normal situation. However, the facts worth paying attention to are that there were many events and accidents which happened in the radioisotope applications, especially at the irradiation facilities. The probability of fatal accident was as high as 10^–3 per irradiator year. In order to improve the radiation safety situation, it is imperative to conduct the safety assessment for irradiation facilities, to enhance management of the radioactive wastes and spent sources and to establish the experience feedback system.