Multifunctional fibrous wound dressings for refractory wound healing

Refractory wounds have always been an important issue to healthcare systems, whose healing process is always delayed by multiple factors, including bacterial infections, chronic inflammation, and excessive exudates, etc. Employing multifunctional wound dressings is recognized as an effective strategy to deal with refractory wounds, which has yielded promising outcomes in recent years. Among these advanced wound dressings, fibrous dressings have gained growing attention due to their unique merits. Such wound dressings have demonstrated great potential in delivering theranostic agents, such as antibacterial agents, anti-inflammatory drugs, growth factors, and diagnostic probes, etc., for the purposes of accelerating wound healing. This paper reviews the development of multifunctional fibrous dressings and their applications in treating refractory wounds. The construction approaches of novel fibrous dressing with capabilities of antibacterial, anti-inflammation, exudate management and diagnosis were also introduced. Furthermore, the existing problems and challenges are also discussed briefly.     

Recent Advances of Freestanding Cathodes for Li-S Batteries

Lithium-sulfur batteries (LSBs) with high energy density and low cost have been recognized as one of the most promising next-generation energy storage systems. Although it has taken decades of development, the practical application of LSBs has been hindered by several inherent obstacles, particularly the severe shuttle effect and sluggish reaction kinetics in the sulfur cathode. Various strategies have been proposed to address these problems via rational design of electrode materials and configurations. Freestanding sulfur cathode could be a promising strategy to improve the sulfur mass loading at the cathode level and energy density of LSBs. This minireview will briefly summary the recent advances in freestanding cathodes for LSBs. The advantages and disadvantages of various freestanding cathodes are discussed and the prospects for the development of flexible cathodes are envisioned.     

Nb(iPrNPMe2)3Fe–PMe3: A potential high reactivity heterobimetallic catalyst for acetylene cycloadditions

Alkynes cycloaddition reactions are powerful tools for constructing cyclic molecules with optimal atom efficiency, but these reactions cannot proceed at ambient temperature without transition-metal catalysts. In this work, a heterobimetallic complex featuring an Nb–Fe triple bond, Nb(ⁱPrNPMe₂)₃Fe–PMe₃, has been evaluated as the potential catalyst for acetylene cycloaddition, using density functional theory. The calculated results show that the singlet-state (i.e. ground-state) Nb(ⁱPrNPMe₂)₃Fe–PMe₃ can be applied to benzene synthesis, but is not suitable for cyclobutadiene. Benzene can be obtained easily at room temperature and is the unique product on the singlet potential surface. The irradiation of infrared-red light can drive the excitation of singlet Nb(ⁱPrNPMe₂)₃Fe–PMe₃ to its triplet state. Both benzene and cyclobutadiene can be formed on the triplet reaction potential surface due to their low energy barriers. Therefore, Nb(ⁱPrNPMe₂)₃Fe–PMe₃ is a potential high reactivity heterobimetallic catalyst for the cyclotrimerization of alkynes. In the reaction process, the catalytic active site of Nb(ⁱPrNPMe₂)₃Fe–PMe₃ moves from niobium to iron.     

A new solution of reducing polymer optical fiber losses

Polymethyl methacrylate (PMMA) is one of the most commonly used optical materials. However, the application of it in the area of optical communication is strongly limited by the intrinsic absorption loss of carbon-hydrogen stretching vibration. In this paper, we present a method to solve the problem by adopting the hollow-core fibers with cobweb cladding structure. The fibers use a single dielectric material and may solve the problem of structural support. Thus the feasibility of the “OmniGuide” fibers is improved, while a series of advantages of the “OmniGuide” hollow-core fiber are retained. It is promising that a fiber with low transmission loss, high bandwidth, large-core, and low costs can be designed and fabricated using PMMA. At the same time, a very broad range of the wavelengths (from visible to near infrared region, for instance, wavelengths at 0.65-1.12 μm, and even 1.30 μm, 1.54 μm and their neighbors) may be adopted for signal wavelength.     

Energy loss effect in high energy nuclear Drell-Yan process

The energy loss effect in nuclear matter, which is a nuclear effect apart from the nuclear effect on the parton distribution as in deep-inelastic scattering process, can be measured best by the nuclear dependence of the high energy nuclear Drell-Yan process. By means of the nuclear parton distribution studied only with lepton deep-inelastic scattering experimental data, the measured Drell-Yan production cross sections for 800 GeV proton incident on a variety of nuclear targets are analyzed within the Glauber framework which takes into account the energy loss of the beam proton. It is shown that the theoretical results with considering the energy loss effect are in good agreement with the FNAL E866 data.Arrival of the final proofs: 24 June 2003     

Au(111)上烷烃硫醇SAMs表面应力的理论研究

应用已建立的关于金属表面吸附层中表面应力的统计热力学理论 ,计算了Au(111)上烷烃硫醇SAMs的表面应力及其与烷烃硫醇链长、吸附覆盖度的定量关系 .计算结果与实验相符 ,较好地解释了Berger等人的实验结果 ,特别是解决了在表面应力符号性质上理论与实验的矛盾 .在表面吸附层应力的多种物理起源中 ,通过底物的分子间作用力有着决定性的贡献 ,揭示了分子的吸附能间接地起着重要作用 .这与阴离子化学吸附体系Cl-/Au(111)的有关研究结果相同 .     

利用半导体光放大器进行光脉冲消基座的理论研究

提出了一种利用半导体光放大器(SOA)联合可调谐光滤波器进行高阶孤子压缩消基座的新方法.进行了详尽的理论分析和优化.数值计算表明,在一定条件下,这种方法能够在不展宽脉冲的前提下,对基座进行有效地抑制.     

The Exact Hausdorff Measure Function of the Level Sets of Multi-parameter Symmetric Stable Process

In this paper, we investigate the Hausdorff measure for level sets of N-parameter Rd-valued stable processes, and develop a means of seeking the exact Hausdorff measure function for level sets of N-parameter Rd-valued stable processes. We show that the exact Hausdorff measure function of level sets of N-parameter Rd-valued symmetric stable processes of index α is Ф（r） = r^N-d/α （log log l/r）d/α when Nα 〉 d. In addition, we obtain a sharp lower bound for the Hausdorff measure of level sets of general （N, d, α） strictly stable processes.     

Fermi能区核－核碰撞的平衡前中子发射

利用ＢＵＵ模型模拟核－核碰撞３６Ａｒ＋１０８Ａｇ（３５Ｍｅｖ／ｕ）、１４Ｎ＋１０８Ａｇ（３５ＭｅＶ／ｕ）中的平衡前中子发射．模拟结果与唯象的运动源拟合给出的中等速度源成份相吻合．这说明中等速度源成份产生于核－核碰撞的早期，对应平衡前发射．并从级联碰撞的角度定量地研究了平衡前发射的持续时间     

ClONO2异构化反应和分解反应的理论研究

用B3LYP/6 31+G(d)和MP2 (Full) /6 31+G(d)优化ClONO2 及其分解反应和异构化反应的过渡态和产物的分子结构 .在B3LYP/6 31+G(d)水平上计算了相关分子的振动频率 .ClONO2 的几何结构、振动频率和红外强度与实验测量值符合得很好 .找到了未曾报道的立体异构体 .对这一立体异构体进行了高级别理论方法CCSD(T) /6 311G(d)和QCISD(T) /6 311G(d)的几何结构优化和振动频率计算 ,表明它是一个稳定的立体异构体 .在所研究的几种反应中 ,ClONO2 分解为NO2 +ClO是最容易进行的反应 .而ClONO2 异构为立体异构体的反应是最难进行的反应 .其所需克服的过渡态的能垒为 4 81.5 2kJ/mol,而反应吸收能量为 2 99.85kJ/mol.次难进行的是ClONO2 经TS1到反应中间体M1,再经TS12而分解为ClNO +O2 的反应 .这个反应通道所需克服过渡态的能垒为 4 2 1.5 5kJ/mol,反应吸收能量为 15 7.98kJ/mol.从以上分析可知 ,和ClO +NO2 反应生成ClONO2 比较 ,ClONO2 具有较好的稳定性 .