pH敏感型智能高分子单链力学性能研究

pH敏感高分子是智能高分子的重要分支,基于其体积、质量或者弹性等参数随pH值变化的性质,可以应用在生物、化学和微/纳机械等多个领域.现有研究多集中在应用领域,缺乏从更深层次的机理上的研究,因此亟需在分子水平上对pH敏感高分子的环境敏感机理进行研究.本工作基于控制变量实验法,利用基于原子力显微镜的单分子力谱技术(SMFS...     

基于密度泛函理论研究掺杂Pd石墨烯吸附O2及CO

基于第一性原理的密度泛函理论研究了单个O₂和CO气体分子吸附于本征石墨烯和掺杂钯(Pd)的石墨烯的体系, 通过石墨烯掺Pd前后气体分子的吸附能、电荷转移及能带和态密度的计算, 发现掺Pd后气体分子吸附能和电荷转移显著增大, 这是由于Pd的掺杂, 在本征石墨烯能带中引入了杂质能级, 增强了石墨烯和吸附气体分子间的相互作用; 氧化性气体O₂和还原性气体CO吸附对石墨烯体系能带结构和态密度的影响明显不同, 本征石墨烯吸附O₂后, 费米能级附近态密度变大, 掺Pd后在一定程度变小; 吸附还原性的CO后, 石墨烯费米能级附近态密度几乎没有改变, 表明掺杂Pd不会影响石墨烯对CO的气体灵敏度, 但由于CO对石墨烯的吸附能增大, 可以提高石墨烯对还原性气体的气敏响应速度.     

手性钌(II)配合物与DNA作用性质的计算研究

理论探索了手性钌(II)配合物1和2与DNA作用性质。首先,构建了手性钌(II)配合物1、2与DNA对接模型,并对对接模型进行了优化,通过计算得到的手性钌(II)配合物1、2与DNA的结合能,解释了手性钌(II)配合物1、2与DNA结合力大小次序,即 Kb(Λ-1) < Kb(∆-1) < Kb(Λ-2) < Kb(∆-2)。另外,通过计算得到的电子转移活化能及自然电荷解释了手性钌(II)配合物1和2光裂解DNA的次序,即Λ-2 > ∆-2 > Λ-1> ∆-1。最后,通过计算得到的对接模型的分子轨道分析了光裂解DNA的原因。     

Numerical simulation of acoustic streaming distribution outside spherical particles under the action of sound waves

Considering the heat loss and viscosity loss inside the acoustic boundary layer,an acoustic streaming calculation model outside a two-dimensional spherical part...     

杜仲及其保健品中生物活性成分的毛细管电泳/电化学检测

采用毛细管电泳/电化学检测法(CE/ED)同时分离测定了杜仲叶、杜仲皮及市售杜仲保健品中芦丁、抗坏血酸、金丝桃甙、绿原酸、槲皮素等多种生物活性成分的含量,考察了运行缓冲液酸度和浓度、分离电压、氧化电位和进样时间等实验参数对分离、检测的影响。在最优化条件下,以300μm碳圆盘电极为检测电极,检测电位为 950 mV(vs.SCE),50 mmol/L硼砂的运行缓冲液(pH9.0)中,上述各组分在20 min内可基本实现基线分离。各组分浓度与峰电流在3个数量级范围内呈良好线性,检出限(S/N=3)在3.3×10-5~9.6×10-5g/L范围。该方法已成功地应用于杜仲及其保健品中生物活性成分的测定,结果令人满意。     

倏逝波全光纤免疫传感器的开发及性能研究

利用倏逝波与荧光免疫分析原理,研制了一种倏逝波全光纤免疫传感器。该系统利用单多模光纤耦合器,使得激发光的传输、荧光的收集与传输均通过光纤来实现,减少了系统的光学分离元件,结构简单、紧凑、可实现仪器小型化;同时该系统光传递效率高、损耗低、信噪比高;单多模光纤耦合器和探头之间采用可拆卸的连接结构,可以实现多种样品的顺序检测。研究表明:光纤探头的最佳锥角度为0.37;系统对Cy5.5荧光染料的检测灵敏度可达到10-9mol/L;系统检测Cy5.5标记的羊抗大鼠IgG的最低浓度为10μg/L,检测时间为10min。     

Limitations of Phage Therapy and Corresponding Optimization Strategies: A Review

Bacterial infectious diseases cause serious harm to human health. At present, antibiotics are the main drugs used in the treatment of bacterial infectious diseases, but the abuse of antibiotics has led to the rapid increase in drug-resistant bacteria and to the inability to effectively control infections. Bacteriophages are a kind of virus that infects bacteria and archaea, adopting bacteria as their hosts. The use of bacteriophages as antimicrobial agents in the treatment of bacterial diseases is an alternative to antibiotics. At present, phage therapy (PT) has been used in various fields and has provided a new technology for addressing diseases caused by bacterial infections in humans, animals, and plants. PT uses bacteriophages to infect pathogenic bacteria so to stop bacterial infections and treat and prevent related diseases. However, PT has several limitations, due to a narrow host range, the lysogenic phenomenon, the lack of relevant policies, and the lack of pharmacokinetic data. The development of reasonable strategies to overcome these limitations is essential for the further development of this technology. This review article described the current applications and limitations of PT and summarizes the existing solutions for these limitations. This information will be useful for clinicians, people working in agriculture and industry, and basic researchers.     

铟酞菁/聚甲基丙烯酸甲酯复合物固体光限幅器性能

将在溶液中表现出优良非线性光学和光限幅性能的铟酞菁及其二聚物嵌入到非光学活性的聚甲基丙烯酸甲酯(PMMA)中, 用传统的旋转涂膜法制备得到具有较高光学质量的复合物薄膜, 用开孔Z-扫描方法在532 nm 处研究了复合物薄膜材料的线性光学和非线性光学性能. 结果表明, 无论是铟酞菁单体还是轴向氧桥联的铟酞菁二聚物, 其PMMA复合材料的光限幅性能均显著优于相应的酞菁分子在溶液中的光限幅性能.     

Multi-Objective Optimization of the Basic and Regenerative ORC Integrated with Working Fluid Selection

A multi-objective optimization based on the non-dominated sorting genetic algorithm (NSGA-II) is carried out in the present work for the basic organic Rankine cycle (BORC) and regenerative ORC (RORC) systems. The selection of working fluids is integrated into multi-objective optimization by parameterizing the pure working fluids into a two-dimensional array. Two sets of decision indicators, exergy efficiency vs. thermal efficiency and exergy efficiency vs. levelized energy cost (LEC), are adopted and examined. Five decision variables including the turbine inlet temperature, vapor superheat degree, the evaporator and condenser pinch temperature differences, and the mass fraction of the mixture are optimized. It is found that the turbine inlet temperature is the most effective factor for both the BORC and RORC systems. Compared to the reverse variation of exergy efficiency and thermal efficiency, only a weak conflict exists between the exergy efficiency and LEC which tends to make the binary objective optimization be a single objective optimization. The RORC provides higher thermal efficiency than BORC at the same exergy efficiency while the LEC of RORC also becomes higher because the bare module cost of buying one more heat exchange is higher than the cost reduction due to the reduced heat transfer area. Under the heat source temperature of 423.15 K, the final obtained exergy and thermal efficiencies are 45.6% and 16.6% for BORC, and 38.6% and 20.7% for RORC, respectively.     

Synergistic Treatment of Congo Red Dye with Heat Treated Low Rank Coal and Micro-Nano Bubbles

In this study, the adsorption method and micro-nano bubble (MNB) technology were combined to improve the efficiency of organic pollutant removal from dye wastewater. The adsorption properties of Congo red (CR) on raw coal and semi-coke (SC) with and without MNBs were studied. The mesoporosity of the coal strongly increased after the heat treatment, which was conducive to the adsorption of macromolecular organics, such as CR, and the specific surface area increased greatly from 2.787 m²/g to 80.512 m²/g. MNBs could improve the adsorption of both raw coal and SC under different pH levels, temperatures and dosages. With the use of MNBs, the adsorption capacity of SC reached 169.49 mg/g, which was much larger than that of the raw coal at 15.75 mg/g. The MNBs effectively reduced the adsorption time from 240 to 20 min. In addition, the MNBs could ensure the adsorbent maintained a good adsorption effect across a wide pH range. The removal rate was above 90% in an acidic environment and above 70% in an alkaline environment. MBs can effectively improve the rate of adsorption of pollutants by adsorbents. SC was obtained from low-rank coal through a rapid one-step heating treatment and was used as a kind of cheap adsorbent. The method is thus simple and easy to implement in the industrial context and has the potential for industrial promotion.