Boosting the advantages of biosensors: Niche applicability and fitness for environmental purpose

Environmental assessments rely on data derived from metrological schemes in order to draw in due detail the state of the ecosystems. The reliability of the data and the cost-effectiveness of the scheme become critical, especially if the ultimate goal involves decision making and policy development. Biosensor platforms provide the versatility required for integrating environmental, metrological and operational parameters at the design phase. The pertinency and the opportunity for environmental biosensing is apparent, although not seized appropriately with only a few environmental biosensors in the market. This study is based on a technology forecasting approach using bibliometric data to trace the dynamics of the science base and content analysis to identify the drawbacks of the technology base. The results are compared with market forecasts in an effort to align research dynamics with market opportunities. A number of key findings emerged, such as the increase in networking and the establishment of a multi-disciplinarity trend, as well as a shifting of research scope towards ready-to-market designing. Notwithstanding, a renewed interest of the physical chemistry sector has been identified herein, indicating necessary revisions of the science-base, adding a critical parameter in the uncertainty of trajectories.     

线形-树状体杂化嵌段共聚物的分子设计、超分子组装及应用

线形-树状体杂化嵌段共聚物是由树枝状高分子嵌段(D)与线形高分子链(L)通过化学键连接而成的一类特殊拓扑结构的共聚物.本文综述了LD两嵌段和DLD三嵌段杂化共聚物的分子设计合成、超分子组装及应用方面近年来的最新研究进展.     

膜技术在中药有效部位和有效成分提取分离中的应用

膜分离具有效率高、能耗低、操作简便、环境友好等优点,在中药制剂生产中呈现出显著的技术优势和广阔的应用前景。本文简要综述了膜技术在中药有效部位和有效成分的提取分离中的应用现状和发展趋势,主要涉及膜分离技术的原理和可行性分析,应用实例。最后指出了膜分离技术的应用要点和需要解决的关键问题等。     

Infrared band intensities: a comparative study of the transition moment matrix elements for the fundamental and overtones: Part II. Application to CO,HCl and OH

The various expressions considered in Part I for the transition moment matrix elements of fundamental and first two overtones are applied to carbon monoxide. The coefficients a_ij in the expressions R^io = Σa_ijp_j (where R^io is the transition moment integral for the O → i vibrational transition and p_j is the dipole moment derivative ?^jP/?XXX^j, XXX = (r — r_e)/r_e, r_e is equilibrium bond distance) are reported for i,j = 1, 2, 3. It is found that these coefficients do not vary by more than 5% when compared for the same i,j values in various expressions irrespective of the most exhaustive treatments used in deriving the original expressions. On the basis of the values of the coefficients obtained for CO, generalisations have been suggested on the effects of inclusion of mechanical and electrical anharmonicity to the intensities of fundamental and first two overtones. It is generally observed that the contribution of p'₁, is about 100 fold more than the contribution of p'₂, for R¹⁰. On the other hand the contributions of p'₁, and p, for R²⁰ and R³⁰ are of nearly equal magnitude but opposite in sign. The contribution of p'₁ to R¹⁰ is much higher than its contribution to R²⁰ and R²⁰. The various observations lead us to conclude that, whereas the effect of inclusion of mechanical anharmonicity on the intensity of the fundamental band is negligible, this effect is almost comparable to the effect of inclusion of electrical anharmonicity for the first two overtones. Simple forms of the a_ij expressions are applied to HC1 and OH to demonstrate the effect of variation of molecular constants on the a_ij values. On the basis of the observed trend in the values of these coefficients for CO, HCl and OH general remarks on the effects of hydrogen bonding on IR band intensities are given.     

光折变聚合物材料的研究进展

本文综述了光折变聚合物材料的发展历史和现状。概括出了这种新型光折变材料的发展思路 ,并汇总了各种类型材料的光折变特性参数。     

无机物对淀粉塑料力学性能影响的研究进展

淀粉以其来源广、成本低、可完全降解的特点已成为制备生物可降解塑料的重要来源。近年来,淀粉塑料的研究和应用发展迅速,其核心是不断提高其各项使用性能(如力学、耐水性能等)。当前,无机或矿物填料被广泛应用于复合材料中来提高材料的性能,本文主要根据无机物的种类不同,综述了典型的氧化物、氢氧化物,以及碳酸盐、硅酸盐、磷酸盐等盐类对淀粉塑料力学性能的影响,归纳了近期的研究成果,分析了该领域研究的热点和难点,并对今后的发展趋势提出了展望。     

Biogenic synthesis of Fe2O3@SiO2 nanoparticles for ipso-hydroxylation of boronic acid in water

Here, biogenic synthesis of Fe₂O₃@SiO₂ nanoparticles using fruit extract of Zanthoxylum rhetsa is reported. The SiO₂ nanoparticles was synthesized using paddy straw which is a byproduct obtained in cultivation of rice. The composite was characterised by spectroscopic method like XRD, SEM, TEM and EDX analysis. The ipso-hydroxylation reactions were carried out with excellent yield within a moderate time period with mild reaction condition in all cases. Therefore, this approach may be considered as simple, easy, cheap and greener, environment friendly protocol for ipso-hydroxylation of arylboronic acids at 50 °C temperature.     

Green synthesis and application of nanoscale zero-valent iron/rectorite composite material for P-chlorophenol degradation via heterogeneous Fenton reaction

A zero-valent iron/rectorite nanocomposite (NZVI/rectorite) was developed as a heterogeneous H₂O₂ catalyst for P-chlorophenol degradation. The physicochemical properties of NZVI/rectorite were characterized by various techniques including X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy-dispersive spectrometry, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller analysis. Results showed that NZVI sphere nanoparticles were successfully loaded on the rectorite surface with less aggregation and good dispersion. Moreover, compared with acid-leached rectorite (30.91 m²/g), the NZVI/rectorite appeared to have larger surface area (50.75 m²/g). In addition, the effects of pH, reaction time, initial P-chlorophenol concentration, catalyst amount, and H₂O₂ dosage on the P-chlorophenol degradation were systematically investigated. Results showed that NZVI/rectorite presents better properties for the degradation and mineralization of P-chlorophenol compared with pristine NZVI due to the large surface area, low aggregation, and good dispersion of the former. The degradation mechanisms of P-chlorophenol by NZVI/rectorite were adsorption and reduction coupled with a Fenton-like reaction. Four successive runs of the stability and regeneration study also showed that the NZVI/rectorite were unchanged even after 100% of P-chlorophenol degradation ratio. This study has extended the application of NZVI/rectorite as environment function material for the removal of P-chlorophenol from the environment.     

Iron-catalyzed C–H amination and its application in organic synthesis

Transition-metal-catalyzed direct C–H bond amination is an attractive strategy in preparation of nitrogen containing molecules which are common in naturally occurring and pharmaceutically important compounds. Comparing to the precious metals commonly used in this reaction, non-precious metals such as iron are abundant in earth, relatively low toxic, and more biocompatible, which meet the increasing demand for environmentally benign and sustainable chemical processes. In this review, we described the development in iron catalyzed C–H bond amination reactions from historical landmarks to recent achievements, and placed emphasis on their applications in organic synthesis, i.e. natural product synthesis and/or modification.     

DEA production games

In this paper, linear production games are extended so that instead of assuming a linear production technology with fixed technological coefficients, the more general, non-parametric, DEA production technology is considered. Different organizations are assumed to possess their own technology and the cooperative game arises from the possibility of pooling their available inputs, collectively processing them and sharing the revenues. Two possibilities are considered: using a joint production technology that results from merging their respective technologies or each cooperating organization keeping its own technology. This gives rise to two different DEA production games, both of which are totally balanced and have a non-empty core. A simple way of computing a stable solution, using the optimal dual solution for the grand coalition, is presented. The full cooperation scenario clearly produces more benefits for the organizations involved although the implied technology sharing is not always possible. Examples of applications of the proposed approach are given.