Inhibitory Effect and Mechanism of Chitosan–Ag Complex Hydrogel on Fungal Disease in Grape

Hydrogel antibacterial agent is an ideal antibacterial material because of its ability to diffuse antibacterial molecules into the decayed area by providing a suitable microenvironment and acting as a protective barrier on the decay interface. The biocompatibility and biodegradation make the removal process easy and it is already widely used in medical fields. However, there have been few reports on its application for controlling postharvest diseases in fruit. In this study, the Chitosan–silver (CS–Ag) complex hydrogels were prepared using the physical crosslinking method, which is used for controlling postharvest diseases in grape. The prepared hydrogels were stable for a long period at room temperature. The structure and surface morphology of CS–Ag composite hydrogels were characterized by UV-Vis, FTIR, SEM, and XRD. The inhibitory effects of CS–Ag hydrogel on disease in grape caused by P. expansum, A. niger, and B. cinerea were investigated both in vivo and in vitro. The remarkable antibacterial activity of CS–Ag hydrogels was mainly due to the combined antibacterial and antioxidant effects of CS and Ag. Preservation tests showed that the CS–Ag hydrogel had positive fresh-keeping effect. This revealed that CS–Ag hydrogels can play a critical role in controlling fungal disease in grapes.     

Study on a new green phosphor Ca12Al14O32Cl2: Tb3+ derived from Tb-doped Ca-Al layered double hydroxide

A new green phosphor Ca₁₂Al₁₄O₃₂Cl₂: Tb³⁺ derived from Tb-doped Ca-Al layered double hydroxide (Tb-doped CaAl-LDH) was prepared through phase transition route. The X-ray diffraction measurement results revealed that the Tb-doped CaAl-LDH transformed into Ca₁₂Al₁₄O₃₂Cl₂:Tb³⁺ phase at 600 °C. With temperature varying from 600, 800–1000 °C, the crystallinity of the Ca₁₂Al₁₄O₃₂Cl₂:Tb³⁺ phase gradually improved. Compositional analyses suggested the chemical formula of the Ca₁₂Al₁₄O₃₂Cl₂:Tb³⁺ phase estimated to be Ca₁₂Al_13.52Tb_0.48O₃₂Cl₂. The Ca₁₂Al_13.52Tb_0.48O₃₂Cl₂ phase can be efficiently excited by near ultraviolet light and show strong green emissions attributed to ⁵D₄→⁷F_J (J = 5, 6) transition of Tb³⁺. The present Ca₁₂Al_13.52Tb_0.48O₃₂Cl₂ may be a promising candidate for green phosphor applied in LED.     

Synthesis of PANI/rGO composite as a cathode material for rechargeable lithium-polymer cells

Graphene oxide (GO) was synthesized by an improved Hummers method and then reduced with NaBH₄; GO became rGO with regular layered structure. Polyaniline (PANI)/rGO composite was prepared by a adsorption double oxidant method with rGO as a template. Some physical characterization methods (Fourier transform infrared spectroscopy analysis, X-ray diffraction, scanning electron microscope, and transmission electron microscope) were used to analyze the morphology and crystallinity of the composite. The electrochemical properties were characterized by cyclic voltammetry, impedance spectroscopy, galvanostatic charge/discharge, and rate capability. The first discharge specific capacity of the rPANI/rGO and PANI/rGO was 181.2 and 147.8 mAh/g. After 100 cycles, the capacity retention rate was still 90.2 and 88.9% separately, and the coulombic efficiency of batteries is close to 100%. These results demonstrate the composite has exciting potentials for the cathode material of lithium-ion battery.     

Synthesis,formation mechanism and electric property of hollow InP nanospheres

The present work reports on novel four-layer thermally driven piezoresistive cantilevers implemented in one- and two-dimensional arrays for parallel proximity scanning. There, the heater (metallic meander), the piezoresistive deflection sensor, and the metal actuation film with significantly higher thermal expansion coefficient make up separate layers. Actuation efficiency and cross-talk of the novel cantilever design are studied and compared with two recent designs: thin metallic film and ion-implanted heater. The novel actuator, integrated on a 240 μm long and 3 μm thick silicon cantilever and supplied by V _dc=1 V enables deflections up to 5 μm of the AFM-tip with an actuation efficiency of about 170 nm/mW and suppressed cross-talk between actuator and sensor.     

蓖麻毒蛋白的提取及分析

本文报道了蓖麻毒蛋白的提取和分析,采用琼脂糖（Sepharose 4B)分离和纯化,研究了高效液相色谱法同时测定蓖麻毒蛋白和蓖麻碱,结果 令人满意。     

A multi-frequency inverse source problem

This paper is concerned with an inverse source problem that determines the source from measurements of the radiated fields away at multiple frequencies. Rigorous stability estimates are established when the background medium is homogeneous. It is shown that the ill-posedness of the inverse problem decreases as the frequency increases. Under some regularity assumptions on the source function, it is further proven that by increasing the frequency, the logarithmic stability converts to a linear one for the inverse source problem.     

A new erythrinan N-oxide alkaloid from Erythrina stricta

This phytochemical study of stems and leaves of Erythrina stricta led to the isolation of twenty-three alkaloids, one of them previously unreported, 11β-hydroxyerythratidine N-oxide. Their structures were elucidated on the basis of extensive 1D and 2D NMR spectroscopic analyses including HSQC, HMBC, ¹H–¹H COSY, NOESY, as well as HRESIMS data in addition to comparison with reports in the literature.     

Infinitely many coexisting conservative flows in a 4D conservative system inspired by LC circuit

Nonlinear Dynamics - Conservative chaotic flows, a category of incompressible chaos, are usually generated from dynamical systems without dissipation. The existing results on conservative chaos are...