Resolving quantum dots and peptide assembly and disassembly using bending capillary electrophoresis

Despite the numerous techniques developed for the studying nanoparticle and peptide interaction nowadays, sensitive and convenient assay in the process of flow, especially to simulate the self‐assembly of quantum dots (QDs) and peptide inflow in blood vessels, still remains big challenges. Here, we report a novel assay for studying the self‐assembly of QDs and peptide, based on CE using a bending capillary. We demonstrate that the semicircles numbers of the bending capillary affect the self‐assembly kinetics of CdSe/ZnS QDs and ATTO‐D₃LVPRGSGP₉G₂H₆ peptide. Moreover, benefitting from this novel assay, the effect of the position on the self‐assembly has also been realized. More importantly, we also demonstrate that this novel assay can be used for studying the stability of the QDs–peptide complex inflow. We believe that our novel assay proposed in this work could be further used as a general strategy for the studying nanoparticle–biomolecule interaction or biomolecule–biomolecule interaction.     

Vertically Grown Few-Layer MoS2 Nanosheets on Hierarchical Carbon Nanocages for Pseudocapacitive Lithium Storage with Ultrahigh-Rate Capability and Long-Term Recyclability

Molybdenum disulfide (MoS₂) is an intensively studied anode material for lithium-ion batteries (LIBs) owing to its high theoretical capacity, but it is still confronted by severe challenges of unsatisfactory rate capability and cycle life. Herein, few-layer MoS₂ nanosheets, vertically grown on hierarchical carbon nanocages (hCNC) by a facile hydrothermal method, introduce pseudocapacitive lithium storage owing to the highly exposed MoS₂ basal planes, enhanced conductivity, and facilitated electrolyte access arising from good hybridization with hCNC. Thus, the optimized MoS₂/hCNC exhibits reversible capacities of 1670 mAh g⁻¹ at 0.1 A g⁻¹ after 50 cycles, 621 mAh g⁻¹ at 5.0 A g⁻¹ after 500 cycles, and 196 mAh g⁻¹ at 50 A g⁻¹ after 2500 cycles, which are among the best for MoS₂-based anode materials. The specific power and specific energy, which can reach 16.1 kW and 252.8 Wh after 3000 cycles, respectively, indicate great potential in high-power and long-life LIBs. These findings suggest a promising strategy for exploring advanced anode materials with high reversible capacity, high-rate capability, and long-term recyclability.     

First-principles study of the co-effect of carbon doping and oxygen vacancies in ZnO photocatalyst

Although tuning band structure of optoelectronic semiconductor-based materials by means of doping single defect is an important approach for potential photocatalysis application,C-doping or oxygen vacancy(Vo)as a single defect in ZnO still has limitations for photocatalytic activity.Meanwhile,the influence of co-existence of various defects in ZnO still lacks sufficient studies.Therefore,we investigate the photocatalytic properties of ZnOx C0.0625(x=0.9375,0.875,0.8125),confirming that the co-effect of various defects has a greater enhancement for photocatalytic activity driven by visible-light than the single defect in ZnO.To clarify the underlying mechanism of co-existence of various defects in ZnO,we perform systematically the electronic properties calculations using density functional theory.It is found that the coeffect of C-doping and Vo in ZnO can achieve a more controllable band gap than doping solely in ZnO.Moreover,the impact of the effective masses of ZnO_xC_0.0625(x=0.9375,0.875,0.8125)is also taken into account.In comparison with heavy Vo concentrations,the light Vo concentration(x=0.875)as the optimal component together with C-doping in ZnO,can significantly improve the visible-light absorption and benefit photocatalytic activity.     

低温燃烧法制备Mn-CeO_x催化剂及其NH_3-SCR脱硝性能

通过低温燃烧法(LCS)制备了不同金属硝酸盐与柠檬酸物质的量比的系列Mn-CeO_x(LCS)锰铈催化剂,将其与共沉淀法(CP)制备的Mn-CeO_x(CP)锰铈催化剂相对比,结合XRD、XPS、FESEM和H2-TPR等技术表征,对其NH_3-SCR脱硝催化性能进行了研究。结果表明,金属硝酸盐与柠檬酸的物质的量比是影响Mn-CeO_x(LCS)催化剂脱硝性能的重要因素。虽然两种催化剂中的锰氧化物组分均为无定型,但相较于Mn-CeO_x(CP),Mn-CeO_x(LCS)表面具有较高的锰含量与Oα/(Oα+Oβ)比,其脱硝催化性能也较高;同时,Mn-CeO_x(LCS)锰铈催化剂上有更多的多级孔,有利于气体在催化剂上的吸附和反应。硝酸盐与柠檬酸物质的量比为36∶22的Mn-CeO_x(LCS)锰铈催化剂在80-180℃下脱硝率可达75%-100%;即使通入SO2,180℃下的脱硝率仍可稳定于74%。     

Implications on cosmic ray injection and propagation parameters from Voyager/ACE/AMS-02 nucleus data

We study the propagation and injection models of cosmic rays using the latest measurements of the boron-to-carbon ratio and fluxes of protons, helium, carbon, and oxygen nuclei by the Alpha Magnetic Spectrometer and the Advanced Composition Explorer at top of the Earth, and the Voyager spacecraft outside the heliosphere. The Advanced Composition Explorer(ACE) data during the same time interval of the AMS-02 data are extracted to minimize the complexity of the solar modulation effect. We find that the cosmic ray nucleus data favor a modified version of the diffusion-reacceleration scenario of the propagation. The diffusion coefficient is, however, required to increase moderately with decreasing rigidity at low energies, which has interesting implications on the particle and plasma interaction in the Milky Way. We further find that the low rigidity( a few GV) injection spectra are different for different compositions. The injection spectra are softer for lighter nuclei. These results are expected to be helpful in understanding the acceleration process of cosmic rays.     

Correlation analysis of cone calorimetry and microscale combustion calorimetry experiments

Flammability studies are conducted to evaluate the behavior of materials exposed to fire. In this study, microscale combustion calorimetry (MCC) and cone calorimetry methods were applied to acquire the flammability characteristics of red and grey extruded polystyrene (XPS) samples. To understand the effect of changes between parameters, Pearson’s correlation coefficient was used to examine their linear relationships. From the research, moderate and weak correlations were recorded between the total heat release rates from both methods for red and grey XPS, respectively. Plotting peak heat release rate against heat release temperature for MCC and ignition temperature for cone test showed that 25, 35 and 50 kW m^?2 incident heat fluxes of the cone test fall within 0.2 K s^?1 and 0.5 K s^?1 heating rates of MCC. Also, all the MCC parameters except char yield and total heat release presented good correlations with the cone calorimetry flammability characteristics. Hence, MCC could be used in conjunction with cone calorimetry to accurately and reliably assess the flammability of materials.

     

印度尼西亚山口洋华人的元宵大游行探析

华人自18世纪就移民到包括山口洋在内的印度尼西亚西加里曼丹,为当地的建设作出了很大的贡献。元宵大游行最初是华人的一种"迎神日"仪式,后来慢慢发展成"神人交汇"的盛大的多民族文化活动。     

0.18μm CMOS高集成度可编程分频器的设计

采用标准0.18 μm CMOS工艺,提出了一种高集成度可编程分频器.该电路所采用技术的新颖之处在于：基于基本分频单元的特殊结构,对除2/除3单元级联式可编程分频器的关键模块进行改进,将普通的CML型锁存器集成为包含与门的锁存器,从而大大提高了电路的集成度,有效地降低了电路功耗,提升了整体电路速度,并使版图更紧凑.仿真结果表明,在1.8V电压、输入频率Fin=1 GHz的情况下,可实现任意整数且步长为1的分频比,相位噪声为-173.1 dBc/Hz@1 MHz,电路功耗仅为9 mW.