Gleaming Uranium: An Emerging Emitter for Building X-ray Scintillators

Scintillators are a unique class of luminescent materials with specific applications towards radiation detection. The emitters within state-of-the-art scintillators are mostly limited to bismuth, cerium, europium, thallium, lead, tungsten, etc. A shared feature of these elements is the relatively high atomic number, which is responsible for high radiation stopping power and radiation-induced luminescence. Searching for new scintillating materials is an essential target aiming at specific applications. In this Concept article, we will discuss our recent works on the topic of “uranyl-bearing scintillators”. As a virgin territory in this field, uranyl-bearing scintillators show intrinsic merits for designing new materials with X-ray detection capability, that is, the large photoelectric cross-section, high X-ray attenuation efficiency, and high crystal density. In addition, we also present challenges in the further development of the uranyl-bearing scintillators.     

Plastic enzyme-linked immunosorbent assays (ELISA)-on-a-chip biosensor for botulinum neurotoxin A

A plastic ELISA-on-a-chip (EOC) employing the concept of cross-flow immuno-chromatographic analysis was applied to the measurement of botulinum neurotoxin A (BoNT/A) as agent for bio-terrorism. Two monoclonal antibodies specific to the heavy chain of the toxin were raised and identified to form sandwich binding complexes as the pair with the analyte. For the construction of an immuno-strip, one was utilized as the capture antibody immobilized onto nitrocellulose membrane and the other as the detection coupled to an enzyme, horseradish peroxidase. The two plates of EOC used in this study were fabricated by injection molding of polycarbonate to improve the reproducibility of manufacture and, after inclusion of the immuno-strip, bonded using a UV-sensitive adhesive. Under optimal conditions of analysis, the chip produced a color signal in proportion to the analyte dose and the signal was quantified using a detector equipped with a digital camera. From the dose-response curve, the detection limit of BoNT/A was 2.0 ng mL⁻¹, approximately five times more sensitive than a commercial-version detection kit employing colloidal gold tracer.     

Azide‐functionalized nanoparticles as quantized building block for the design of soft–soft fluorescent polystyrene core—PAMAM shell nanostructures

This work deals with the covalent coupling of azide‐functionalized polymeric nanoparticles as a reactive core and amino‐terminated PAMAM dendrons as a reactive shell. The nanoassemblies thereby obtained could be modified after the dendronization step by grafting an alkynyl Bodipy dye on the unreacted azide moieties. Only a few steps are required to attain nanoassemblies that could mimic dendrimers of high generation with sizes of nano‐objects beyond those of dendrimers. The structure of the nanoassemblies are composed of a polystyrene core, an inner shell including the Bodipy dyes along with the internal branches of the PAMAM, and the terminal amino groups from the outer shell. The dendritic shell acts as a protective layer that prevents NP from aggregation in a surfactant free aqueous solution. The nano‐objects display absorption and emission maxima above 500 nm with brightness that are the same order of magnitude than Qdots. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 115–126     

Brij35增敏荧光法测定塑料饮料瓶中双酚A

建立了测定塑料饮料瓶中双酚A的Brij35增敏荧光分析法.实验考察了不同介质及pH、静置时间、介质用量、金属离子等因素对双酚A(BPA)荧光强度的影响.结果表明,在所探讨的7种介质中Brij 35荧光增敏效果最好,据此建立了一种用Brij35增敏荧光光度法测定双酚A的新方法.方法线性范围为2.0×10-8～1.0×10-5 mol/L,检出限为2.5×10-8 mol/L,相对标准偏差为1.92％.该方法快速、简便、灵敏度高,对实际样品塑料饮料瓶中双酚A的检测,结果满意.     

Scratch and Abrasion Resistant Coatings on Plastic Lenses—State of the Art,Current Developments and Perspectives

The manufacturing of ophthalmic lenses is one of the most important markets worldwide and, therefore, strong research efforts are undertaken to continuously improve the quality of the products, either silicate glasses or organic polymer lenses. Hybrid sol-gel based materials play a major role in this highly competitive field and have contributed significantly to the commercial success of the organic base materials. Recent developments concern fast curing and patternable coatings that might soon become part of this business. The compatibility of hybrid sol-gel materials either with organic dyes or with inorganic vacuum borne coatings offers further possibilities to develop highly sophisticated lenses meeting not only customer needs like perfect corrective function, high optical quality and protection, but also high durability as well as cosmetic and decorative aspects. An overview and a few recent developments are outlined below.     

Novel side‐chain naphthalimide polyphenylacetylene as a ratiometric fluorescent chemosensor for fluoride ion

Novel polyphenylacetylene ( P1 ) containing naphthalimides units in the side chain was designed and synthesized. The structure and properties of the polymer were characterized and evaluated by IR, NMR, UV, and PL. The measurements of sensing behavior to various halide anions, that is, F^?, Cl^?, Br^?, and I^?, reveal that the polymer is a ratiometric fluorescent chemosensors for fluoride ion. The polymer sensor shows spectral shifts and intensity changes in the presence of fluoride, in a wavelength‐ratiometric and ‐colorimetric manner, which can detect fluoride concentrations in range of 10–100 μM at visible wavelengths. The obvious colorless‐to‐yellow color change and blue‐to‐orange emission color change on the addition of fluoride ion are easily observed by naked eyes. It provides a feasible way to construct a ratiometric fluorescent chemosensors for fluoride ion. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1544–1552, 2009     

General Discussion on Chemical Modifications

Recent work on the use of wool in heat- and mass-exchange systems is summarized. Improvements in the transfer of water vapor (e.g., between the inlet and outlet ducts of an air conditioner) have been obtained by application of hydrophilic polymers to the surface of wool fibers. Further improvements in water sorption are obtained by inclusion of deliquescent salts. Drip formation does not occur at high humidities, presumably because of the viscous nature of the polymer/water system. Wool is shown to be a more suitable substrate than polyester.     

Status and dreams of photonics polymer for IT

We have proposed a low-loss, high-bandwidth and large-core graded-index plastic optical fiber (GI POF) in data-corn, area. The GI POF enables us to eliminate the “modal noise” problem which is observed in medium-core silica fibers. Therefore, stable high-speed data transmission can be realized by the GI POF rather than medium-core silica fibers. Furthermore, advent of perfluorinated (PF) polymer based GI POF network can support higher transmission than silica fibers network because of the small material dispersion of PF polymer compared with silica. In addition, we proposed a “highly scattering optical transmission (HSOT) polymer” and applied it to a light guide plate of a liquid crystal display backlight. The HSOT polymer backlight that was designed using the HSOT designing simulator demonstrated twice the brightness of the conventional taransparent backlight with sufficient color uniformity. Furthermore, we proposed the two types of zero-birefringence polymers synthesized by the random copolymerization method and the anisotropic molecule dopant method. Both of the polymers exhibited no orientational birefringence for any orientation of polymer chains.     

Deep‐red emissive conjugated poly(2,6‐BODIPY‐ethynylene)s bearing alkyl side chains

Novel deep‐red emissive poly(2,6‐BODIPY‐ethynylene)s bearing dodecyl side chains (polymers A , B , and C ) have been prepared by palladium‐catalyzed Sonogashira polymerization of 2,6‐diiodo‐functionalized BODIPY monomers with 2,6‐diethynyl‐functionalized BODIPY monomers. These polymers emit in the deep‐red region with emission maxima at up to 690 nm, and exhibit significant red shifts (up to 166 and 179 nm) of both absorption and emission maxima compared with their parent BODIPY dyes due to significant extension of π‐conjugation. These polymers possess good thermal stability with decomposition temperature between 270 and 360 °C. The polymers exhibit a little larger Stokes shifts and shorter lifetime than their corresponding BODIPY dyes. The solid state thin films of polymers A , B , and C emit in near‐infrared region between 723 and 743 nm, and show significantly red shifts (up to 57 nm) in absorption and emission maxima relative to their polymer solution. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5354–5366, 2009     

一种新型吡唑啉类染料荧光性质的研究

本文利用紫外吸收、荧光光谱、偏振荧光和时间分辨瞬态光技术,研究了1-对氨硫酰苯基-3-对氯苯基吡唑(SCPL)在不同溶剂     

Synthesis,electrochemical, and optical properties of low band gap homo‐ and copolymers based on squaraine dyes

A broad series of monomeric and polymeric squaraines was synthesized to investigate the impact of electron‐donating bridges, such as unsaturated triarylamine, carbazole, and saturated piperazine groups, on the spectroscopic and redox properties. These bridges were attached to both standard trans‐indolenine squaraines and dicyanomethylene‐substituted cis‐indolenine squaraines. The conjugates were investigated by absorption, steady‐state, and time‐resolved fluorescence spectroscopy and cyclic voltammetry. While addition of the donors resulted in significant redshift of the absorption of the model compounds, hardly any further shift or broadening was observed for the copolymers. Also the redox properties remained nearly unchanged compared with the model dyes. In contrast, immense broadening and redshift was observed for homopolymers. This behavior is explained by mostly excitonic coupling of localized squaraine transitions. The increasing distance of the chromophores determined by the bridges led to a decrease of the exciton coupling energy. We also performed semiempirical CNDO/S2 calculations on AM1 optimized structures. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 890–911     

The use of naphthalene fluorescence probes to study the binding sites on cyclodextrin polymers formed from reaction of cyclodextrin monomers with epichlorohydrin

Three naphthalene-based fluorescence probes were used as guest molecules to study host/guest binding with cyclodextrin (CD) polymer hosts prepared by treating -,-, or -cyclodextrin monomers with epichlorohydrin. The fluorescence data indicate that the binding interaction is much stronger for the probes with the CD polymers than with the CD monomers. Moreover, the fluorophore binding site on the CD polymers is also more hydrophobic than that on the CD monomers. Fluorescence lifetime data from one of the bound probes (2-(N-methylanilino) naphthalene-6-sulfonic acid) suggest that more than one type of binding site may exist on the CD polymers with this probe. A comparison of fluorescence data using different molecular weight ranges of the CD polymers appear to rule out the possibility of a 12 host/guest complex, where the two CD units come from the same polymer chain.     

磁共振/光学双模态分子探针的研究现状与展望

基于磁共振与荧光成像的双模态成像技术不仅克服了传统单一分子影像技术在灵敏度、特异度、分辨率等方面的固有缺陷，更是拓宽了分子影像技术在诊断及治疗监控等领域的研究范围及应用前景。本文将对磁共振/荧光双模态分子探针的应用情况和研究进展等进行综述。     

Single-molecule spectroscopy of uniaxially oriented terrylene in polyethylene.

Single terrylene molecules doped into linear low-density polyethylene can be oriented by tensile deformation of the matrix. In measurements on ensembles at ambient and on single terrylene molecules at cryogenic temperature, strong orientation along the stretching direction was observed by polarization-resolved confocal microscopy. At cryogenic temperatures narrow and spectrally stable zero-phonon lines were found. The low saturation intensity of 0.07 W cm(-2) is consistent with an uniaxial orientation of terrylene in the sample plane.     

Cooperative Supramolecular Polymerization: Comparison of Different Models Applied on the Self‐Assembly of Bis(merocyanine) Dyes

Three new molecular building blocks 1 a – c for supramolecular polymerization are described that feature two dipolar merocyanine dyes tethered by p‐xylylene spacers. Concentration‐ and temperature‐dependent UV/Vis spectroscopy in chloroform combined with dynamic light scattering, capillary viscosimetry and atomic force microscopy investigations were applied to elucidate the mechanistic features of the self‐assembly of these strongly dipolar dyes. Our detailed studies reveal that the self‐assembly is very pronounced for bis(merocyanines) 1 a , b bearing linear alkyl chains, but completely absent for bis(merocyanine) 1 c bearing sterically more bulky ethylhexyl substituents. Both temperature‐ and concentration‐dependent UV/Vis data provide unambiguous evidence for a cooperative self‐assembly process for bis(merocyanines) 1 a , b , which was analyzed in detail by the Meijer–Schenning–Van‐der‐Schoot model (applicable to temperature‐dependent data) and by the Goldstein–Stryer model (applicable to concentration‐dependent data). By combining both methods all parameters of interest to understand the self‐assembly process could be derived, including in particular the nucleus size (8–10 monomeric units), the cooperativity factor (ca. 0.006), and the nucleation and elongation constants of about 10³ and 10⁶ M ^?1 in chloroform at room temperature, respectively.     

Photostable, amino reactive and water-soluble fluorescent labels based on sulfonated rhodamine with a rigidized xanthene fragment

Highly water soluble fluorescent dyes were synthesized and transformed into new amino reactive fluorescent labels for biological microscopy. To this end, rhodamine 8 (prepared from 7-hydroxy-1,2,3,4-tetrahydroquinoline (7) and phthalic anhydride in 85 % aq. H(3)PO(4)) was sulfonated with 30 % SO(3) in H(2)SO(4) and afforded the water soluble disulfonic acid 3 a (64 %). Amidation of the carboxy group in 3 a with 2-(methylamino)ethanol in the presence of O-(7-azabenzotriazol-1-yl)-N,N,N',N'-tetramethyluroniumPF(6) (-) (HATU) led to alcohol 3 b (66 %), which was transformed into the amino reactive mixed carbonate 3 d with di(N-succinimidyl)carbonate and Et(3)N. Reaction of the carboxy group in 3 a with MeNH(CH(2))(2)CO(2)Me and N,N,N',N'-tetramethyl-O-(N-succinimidyl)-uroniumBF(4) (-) (TSTU) yielded methyl ester 13. After saponification of the aliphatic carboxy group in 13, the compound was converted into NHS-ester 3 e (using HATU and Et(3)N). Heating of 7 with trimellitic anhydride in H(3)PO(4) gave a mixture of dicarboxylic acids 14 and 15 (1:1). Regioisomer 15 was isolated, sulfonated with 30 % SO(3) in H(2)SO(4), and disulfonic acid 3 f was used for the synthesis of the mono NHS-ester 3 g, in which the sterically unhindered carboxy group was selectively activated (with N-hydroxysuccinimide, HATU, and Et(3)N). The sulfonated rhodamines 3 b, c and f are soluble in water (up to 0.1 M), have excellent photostabilities and large fluorescence quantum yields. Subdiffraction resolution images of tubulin filaments of mammalian cells stained with these dyes illustrate their applicability as labels for stimulated emission depletion microscopy and other fluorescence techniques.     

High sensitivity sensing of nitroaromatic explosive vapors based on polytriphenylamines with AIE‐active tetraphenylethylene side groups

Two polytriphenylamines (PTPAs) (P1 and P2) with aggregation induced emission (AIE)‐active tetraphenylethylene side groups have been designed and successfully synthesized. Both polymers only faintly emit in dilute solution but show strong emission in aggregated state, meaning that they are AIE‐active. The detection of 1,3,5‐trinitrobenzene (TNB) vapors has been investigated by photoluminescence (PL) quenching in polymer films. High solid state quantum yields and donor‐acceptor interactions of the electron‐rich PTPA chains with the TNB analyte, hereby, induce a high sensing sensitivity, both for P1 and P2 films towards TNB vapor. Contacting thin P1 and P2 films with saturated TNB vapor, the PL intensity was quenched by 85% for P1 and 89% for P2 within 600 s, respectively. The sensing process is reversible, >90% of the PL is recovered, also after repeated cycling. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 53, 1753–1761     

镶炭泡塑对阴离子表面活性剂吸附性能的研究

提出了用镶炭泡塑处理含阴离子表面活性剂的废水，并通过实验证实，经活化的泡塑对ＬＡＳ有明显的富集作用，且发现将活化过的活性炭填镶进去，可形成具有复合功能的处理剂，对含ＬＡＳ废水的处理效果更佳。