Improved Current-Monitoring Method for Low Electroosmotic Flow Measurement in Modified Microchip

Current-monitoring method is a widely used approach to measure electroosmotic flow (EOF) in microchip, but low and zero EOF is difficult to be measured. In this report, the mechanism of current-monitoring method was explained with Kohlraush regulation function principle, and an improved current-monitoring method was developed for low EOF measurement with tilting microchip. Fluid flow in the channel was accelerated with the help of hydrostatic pressure generated by tilting microchip, the time of dilute solution displacing the concentrated one in channel was shortened. EOF could be calculated according to the time difference between twice experiments under two different applied voltages by tilting microchip. Low even zero EOF could be measured by this improved current-monitoring method. Three modified microchips were characterized to verify the method. EOF in microchannels modified with poly(vinyl alcohol), bovine serum albumin and myoglobin were 0.27 ± 0.05, 0.16 ± 0.05 and ?0.45 ± 0.04 × 10^?4 cm² V^?1 s^?1, respectively.     

Two Manganese Halide Hybrids Based on 1-Butyl-2,3-dimethylimidazolium: Synthesis,Crystal Structure and Photoluminescence

Two new inorganic-organic hybrid manganese(II) halide crystals,namely[BMMIm]_2[MnCl_4](1,BMMIm=1-butyl-2,3-dimethylimidazolium) and[BMMIm]_2[MnBr_4](2),have been obtained simply by heating/stirring with nearly 100%yield.Single-crystal X-ray diffraction (SCXRD) study reveals that 1 crystallizes in triclinic space group of P1 with a=10.0176(7),b=14.9603(11),c=12.9086(8)?,a=91.060(4)°,β=110.204(5)°,g=92.361(4)°,V=1235.19(12)?~3,Z=2,D_c=1.353 g·cm~(-3),F(000)=526,μ=0.978 mm~(-1),R=0.0410 and w R=0.0690 (I2σ(I)) and M_r=503.23;2 belongs to orthorhombic space group of P2_12_12_1 with a=10.0176(7),b=14.9603(11),c=17.4450(14)?,V=2614.4(3)?~3,Z=4,D_c=1.730 g·cm~(-3),F(000)=1340,μ=6.629 mm~(-1),R=0.0440 and w R=0.0520 (I2σ(I)) and M_r=681.07.The ionic compounds 1 and 2 are composed of mononuclear tetrahedral[Mn X_4]~(2-)anion and two ionic liquid cations of[BMMIm]~+.The photoluminescence (PL)of 1 and 2 was characterized and the influence of halogen atom types on PL was investigated.     

A self-powered and drug-free diabetic wound healing patch breaking hyperglycemia and low H2O2 limitations and precisely sterilizing driven by electricity

Accelerating diabetes-related chronic wound healing is a long-sought-after goal in diabetes management. However, therapeutic strategies based on antibiotics or catalysts still face great challenges to break the limitations of antimicrobial resistance, low H₂O₂ and the blocking effect of bacterial biofilms on antibiotic/catalyst penetration. Herein, we reported a glucose biofuel cell-powered and drug-free antibacterial patch, which consisted of an MAF-7 protected glucose oxidase/horseradish peroxidase anode and a horseradish peroxidase cathode, for treating diabetic wounds. This self-powered patch could take high blood glucose as fuel to generate electricity and abundant reactive oxygen species (ROS) in situ, synergistically regulating local hyperglycemia and breaking the limitations of insufficient ROS caused by low H₂O₂ levels. In particular, the electric field created by the GBFC could drive the negatively charged bacteria to adhere firmly to the electrode surface. As a result, the ROS produced in situ on the electrodes was localized to the bacteria, realizing precise sterilization. In vivo experiments confirmed that this self-powered patch enabled the wounds on diabetic mice to take a mere 10 days to eliminate inflammation and form mature skin with new hair follicles, demonstrating its great potential in treating bacteria-infected diabetic wounds.

A GBFC-powered antibacterial patch which can break low H₂O₂ limitations and precisely sterilize driven by electricity was created to treat bacteria-infected diabetic wounds without depending on any exogenous drugs.     

高浓度CO2气氛下燃煤氮、硫污染物的释放特性

采用污染物在线分析仪、气相便携红外分析仪研究了程序升温条件下改变氧化介质时煤中氮,硫的释放特性以及含硫物相的浓度变化规律,探讨了不同气氛,CO2浓度与O2浓度单独变化时对NO、SO2析出特性的影响机理.结果表明:O2/CO2燃烧气氛下NO、SO2排放峰值及总量均低于O2/N2气氛.CO2气氛下烟气中存在大量的CO,有利于NO的降解,同时也促进了烟气中其他含硫物相的形成,随着CO2浓度的增加,特别是在燃烧后期,NO、SO2的排放显著降低.O2浓度改变对NO和SO2的释放影响不同:O2浓度升高促进了SO2的析出;但是O2浓度在一定范围内增加对NO的排放并无明显影响,随着O2浓度进一步增加,NO的释放峰向低温区迁移,同时排放量降低.     

Neutron beam monitor based on a boron-coated GEM

A new thermal neutron beam monitor with a Gas Electron Multiplier (GEM) is developed to meet the needs of the next generation of neutron facilities. A prototype chamber has been constructed with two 100 mm×100 mm GEM foils. Enriched boron-10 is coated on one surface of the aluminum cathode plate as the neutron convertor. 96 channel pads with an area of 8 mm×8 mm each are used for fast signal readout. In order to study the basic characteristics of a boron-coated GEM, several irradiation tests were carried out with α source ²³⁹Pu and neutron source ²⁴¹Am(Be). The signal induced by the neutron source has a high signal-to-noise ratio. A clear image obtained from α source ²³⁹Pu is presented, which shows that the neutron beam monitor based on a boron-coated GEM has a good two-dimensional imaging ability.     

Synthesis and Crystal Structure of 15,16-Bis（（4-nitrophenoxy）methyl）-2,3,5,6,8,9,11,12- octahydrobenzo[b][1,4,7,10,13]pentaoxacyclopentadecine

Double-armed crown ether 15,16-bis((4-nitrophenoxy)methyl)-2,3,5,6,8,9,11,12-octahydrobenzo[b][1,4,7,10,13] pentaoxacyclopentadecine F.W. 570.54 was synthesized by dibromomethyl benzo-15-crown-5 with 4-nitrophenol in the presence of anhydrous K2CO3, characterized by spectroscopic techniques and confirmed by X-ray crystal structure analysis. The title compound crystallizes in monoclinic, space group P21/c with a = 12.840(4), b = 9.425(3), c = 22.447(7), β = 98.128(7)° and Z = 4. The structure exhibits intermolecular hydrogen bonding of C-H···O type.     

Cooperative template-directed assembly of mesoporous metal-organic frameworks

Despite great efforts, the development of a reliable way to assemble mesoporous metal-organic frameworks (mesoMOFs) remains a challenge. In this work, we have designed a cooperative template system, comprising a surfactant (cetyltrimethylammonium bromide) and a chelating agent (citric acid), for the generation of a mesoMOF containing a hierarchical system of mesopores interconnected with microspores. The surfactant molecules form micelles and the chelating agent bridges the MOF and the micelles, making self-assembly and crystal growth proceed under the direction of the cooperative template. However, when the surfactant or the chelating agent was applied individually, no mesoMOF was obtained.     

光谱图像技术结合SAM算法识别自然场景下的成熟柑橘

为了实现采摘机器人在复杂的自然场景下正确识别树上果实,来完成果实采摘,研究了不同环境下柑橘的识别方法.针对复杂的自然环境的影响及传统方法的局限性,在可见光和近红外区域择选5个特征波长滤波片,采集得到5幅滤波后的图像,并利用光谱角分类算法完成柑橘识别.试验结果表明,在光照角度、光照强度等不同条件下,柑橘的识别准确度达到96%.研究表明,滤波片光谱图像技术结合光谱角分类算法可以有效地识别自然场景下的成熟柑橘.     

单光束飞秒激光诱导微纳周期结构的现象与机理

飞秒激光具有超快和超强（聚焦后局域电场达到10^10V／cm，相当于氢原子的库仑场强）的特点，因此它与材料发生相互作用时会产生多光子吸收、多光子电离、自聚焦等非线性效应．文章介绍最近发现的单光束飞秒激光在物质内部诱导自组装纳米光栅，沿光束传播方向排列成行的纳米周期孔洞结构以及材料表面诱导纳米周期结构等新现象，并对这些现象的机理作了阐述．