CaO assisted mechanochemical remediation of lindane-contaminated soil.

In this study, the planetary ball milling with CaO addition was used to remediate lindane-contaminated soil. Based on Hertzian theory, a mathematical model was proposed to simulate the trajectory of grinding ball and the local energy transfer during a planetary operation at the disk rotation velocities of 150-250 rpm. Besides, the influence of different parameters on lindane removal in soil was investigated, whose results showed that disk rotation velocity and reagent-to-soil ratio had a positive effect, while soil moisture, initial concentration of lindane, and mass of polluted soil demonstrated a negative influence. The mechanochemical method exhibited a higher degradation performance at 3 wt% CaO addition, and a disk rotation velocity of 250 rpm. Active species generated by ball collisions in the presence of CaO, especially superoxide (·O2-) demonstrated a significant role in participating in the lindane conversion. In combination with GCMS and XPS analysis, the proposed model provides insight into mechanochemical remediation process from physical and chemical perspectives, which mainly includes four main steps: mixing, inducing, chemical reaction, and structure destruction.

Investigation of lethal thresholds of nanosecond pulsed electric field in rabbit VX2 hepatic tumors through finite element analysis and verification with a single-needle bipolar electrode: A prospective strategy employing three-dimensional comparisons.

Pulsed electric field has emerged as a promising modality for the solid tumor ablation with the advantage in treatment planning, however, the accurate prediction of the lesion margin requires the determination of the lethal electric field (E) thresholds. Herein we employ the highly repetitive nanosecond pulsed electric field (RnsPEF) to ablate the normal and VX2 tumor-bearing livers of rabbits. The ultrasound-guided surgery is operated using the conventional double- and newly devised single-needle bipolar electrodes. Finite element analysis is also introduced to simulate the E distribution in the practical treatments. Two- and three-dimensional investigations are performed on the image measurements and reconstructed calcification models on micro-CT, respectively. Specially, an algorithm considering the model surface, volume and shape is employed to compare the similarities between the simulative and experimental models. Blood vessel injury, temperature and synergistic efficacy with doxorubicin (DOX) are also investigated. According to the three-dimensional calculation, the overall E threshold is 4536.4 ± 618.2 V/cm and the single-needle bipolar electrode is verified to be effective in tissue ablation. Vessels are well preserved and the increment of temperature is limited. Synergy of RnsPEF and DOX shows increased apoptosis and improved long-term tumor survival. Our study presents a prospective strategy for the evaluation of the lethal E threshold, which can be considered to guide the future clinical treatment planning for RnsPEF.

A Molecular Polycrystalline Ferroelectric with Record-High Phase Transition Temperature.

An outstanding advantage of inorganic ceramic ferroelectrics is their usability in the polycrystalline ceramic or thin film forms, which has dominated applications in the ferroelectric, dielectric, and piezoelectric fields. Although the history of ferroelectrics began with the molecular ferroelectric Rochelle salt in 1921, so far there have been very few molecular ferroelectrics, with lightweight, flexible, low-cost, and biocompatible superior properties compared to inorganic ceramic ferroelectrics, that can be applied in the polycrystalline form. Here, a multiaxial molecular ferroelectric, guanidinium perchlorate ([C(NH2 )3 ]ClO4 ), with a record-high phase transition temperature of 454 K is presented. It is the rectangular polarization-electric field (P-E) hysteresis loops recorded on the powder and thin film samples (with respective large Pr of 5.1 and 8.1 µC cm-2 ) that confirm the ferroelectricity of [C(NH2 )3 ]ClO4 in the polycrystalline states. Intriguingly, after poling, the piezoelectric coefficient (d33 ) of the powder sample shows a significant increase from 0 to 10 pC N-1 , comparable to that of LiNbO3 single crystal (8 pC N-1 ). This is the first time that such a phenomenon has been observed in molecular ferroelectrics, indicating the great potential of molecular ferroelectrics being used in the polycrystalline form like inorganic ferroelectrics, as well as being viable alternatives or supplements to conventional ceramic ferroelectrics.

Unusual Hollow Al2O3 Nanofibers with Loofah-Like Skins: Intriguing Catalyst Supports for Thermal Stabilization of Pt Nanocrystals.

Recently, hollow nanofibers could be fabricated by coaxis electrospinning method or template method. However, they are limited to applications because of the hardship in actual preparation. In this work, hollow γ-Al2O3 nanofibers with loofah-like skins were first fabricated by using a single spinneret during electrospinning. These intriguing nanofibers were explored as new Pt supports with excellently sinter-resistant performance up to 500 °C, attributed to the unique loofah-like surface of γ-Al2O3 nanofibers and the strong metal-support interactions between Pt and γ-Al2O3. When applied in the catalytic reduction of p-nitrophenol, the Pt/γ-Al2O3 calcined at 500 °C exhibited 4-times higher reaction rate constant (6.8 s-1·mg-1) over free Pt nanocrystals.

Self-assembly of defect-rich graphene oxide nanosheets with Na2Ti3O7 nanowires and their superior absorptive capacity to toxic dyes.

Graphene sheets, a flexible 2D material with excellent absorptive capacity, have great potential as absorbing materials. However, this material has always suffered from irreversible aggregation and thus loses the abundant active sites and large surface area. In this paper, large-scale graphene oxide (GO) sheets were cut and reduced to tiny reduced graphene oxide (RGO) sheets by a cell-break sonicator, for producing numerous defects, which are the center of chemisorption. Furthermore, sodium titanate nanowires functioned as a framework to help to disperse the tiny RGO sheets uniformly. And, in turn, the flexible tiny RGO sheets glued robust nanowires into a free-standing membrane. This novel composite membrane exhibited an ultra-high decoloration efficiency of 99.8% of rhodamine B in a continuous flow mode, and an outstanding absorptive capability of 1.30 × 10-2 mol g-1 correlated to RGO content in batch reaction, which is about two orders of magnitude higher than other reported graphene-based absorbents. In addition, an efficient and feasible method without any heat treatment for regenerating the membrane is illustrated, and the recycled membrane retains superior decoloration efficiency. The excellent absorptive performance indicates the framework-based disperse strategy has great potential for the construction and application of defect-rich graphene.

A Three-Dimensional Molecular Perovskite Ferroelectric: (3-Ammoniopyrrolidinium)RbBr3.

It is known that CH3NH3PbI3 is particularly promising for next-generation solar devices; therefore, molecular perovskite structures have recently received extraordinary attention from the academic community because of their potential in producing unique physical properties. However, although great efforts have been made, molecular ferroelectrics with three-dimensional (3D) perovskite structures are still rare. So far, reported perovskite-like molecular ferroelectrics are basically one- or two-dimensional, significantly deviating from the inorganic perovskite ferroelectrics. Thus, their ferroelectric properties have to be greatly improved to meet the requirements of practical applications. Here, we report a 3D molecular perovskite ferroelectric: (3-ammoniopyrrolidinium)RbBr3 [(AP)RbBr3], with a high Curie temperature (Tc = 440 K) beyond that of BaTiO3. To the best of our knowledge, such above-room-temperature ferroelectricity in the 3D molecular perovskite compound is unprecedented. Furthermore, (AP)RbBr3 has great potential for applications due to its high thermal stability, ultrafast polarization reversal (greater than 20 kHz), and fascinating multiaxial characteristic. This finding opens a new avenue to the design and controllable synthesis of molecular ferroelectric perovskites, where the metal ion, halogen ion, and organic cation can be easily tuned.

[Effect of compound Danshen Dripping Pill on carotid arterial intima-media in patients with type 2 diabetes mellitus].

OBJECTIVE: To investigate the effect of compound Danshen Dripping Pill (DSP) on carotid arterial intima-media thickness (IMT) in patients with type 2 diabetes mellitus (T2DM). METHODS: One hundred and thirty T2DM patients were assigned to four groups, 32 in the Group A, the control group treated with blood glucose (BG) and blood pressure (BP) controlling; 32 in the Group B, with BG, BP and blood lipid (BL) controlling, 32 in Group C with BG, BP, BL controlling and vitamin E administration, and 34 in Group D with BG, BP, BL controlling and DSP administration. Patients in Group D were subdivided by Chinese medicine syndrome differentiation into four types, 8 of Yin-deficiency with flourishing heat type (YDFH), 5 of both qi-yin deficient type (BQYD), 8 of both yin-yang deficient type (BYYD) and 13 of blood-stasis and qi-stagnant type (BSQS). Fasting blood glucose (FBG), BP and BL in patients were observed periodically, and IMT in them were measured by ultrasonography before treatment, as well as at the end of the 1st, 3rd, and 5th year of treatment to dynamically observe the changes of IMT and condition of plaque formation, and analyze the relation between them with FBG, BP and BL. RESULTS: The 5-year follow-up was performed in 105 patients. In the observation period, level of total cholesterol (TC) showed a decreasing trend and level of high density cholesterol (HDL-C) showed an increasing trend in all the 4 groups, the improvements in Group C and D were slightly better than those in Group B, while significantly superior to those in Group A; the changes of FBG and glycosylated hemoglobin (HbAlc) were insignificant in the 4 groups. IMT and numbers of atheroma plaque increased gradually in all groups in the observation period, however, the changes in Group D were lesser than those in other groups, showing significant difference (P < 0.01). It was showed that the increasing of cervical carotid IMT in T2DM patients was correlated with levels of HbAlc, HDL-C, LDL-C, triglyceride and TC, especially in Group D. CONCLUSION: DSP might delay the occurrence and development of diabetic macro-vascular disease.