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With the gradual shift of coal mining to deeper levels in recent years, rock burst has become one of the primary dynamic hazards faced in deep mining. It has been shown that the pore structure in rocks affects the mechanical properties, but the relationship with the rock burst phenomenon still needs to be clarified. In this paper, we investigated the causes and effects of pore structure on impact mechanical properties using RFPA2D numerical simulation software, established several numerical models with different porosities and pore diameters, and analyzed the stress-strain curves, the relationships between porosity and pore diameter and each the bursting liability indices of the coal rock body were elaborated, and the fitting equations in the range of porosity (0%~10%) and pore diameter (0.25~2.0 mm) were obtained. The results showed that the increase in porosity and pore diameter effectively attenuated the bursting ability of coal rocks, which has some reference significance for the study of early warning and prevention of rock burst phenomenon.

Coal mine safety may be able to be ensured via the real-time identification of cracks in rock and coal surfaces. Traditional crack identification methods have the disadvantages of slow speed and low precision. This work suggests an improved You Only Look Once version 5 (YOLOv5) detection model. In this study, we improved YOLOv5 from the perspective of three aspects: a Ghost module was introduced into the backbone network to lighten the model; a coordinate attention mechanism was added; and ECIOU_Loss is proposed as a loss function in this paper to achieve the co-optimization of crack detection speed and accuracy and to meet the deployment requirements in the embedded terminal. The results demonstrate that the improved YOLOv5 has a 92.8% mean average precision (mAP) with an 8 MB model size, and the speed of recognition was 103 frames per second. Compared to the original method, there was a 53.4% reduction in the number of parameters, a detection speed that was 1.9 times faster, and a 1.7% improvement in the mAP. The improved YOLOv5 can effectively locate cracks in real time and offers a new technique for the early warning of coal and rock dynamic hazards.

The paper introduces a new type of large-scale coal mine dust monitoring and efficient treatment technology, which realizes online continuous monitoring and control of mine dust concentration, and can transmit the dust concentration at the detection point to the underground control system in real time, realizing intelligent coal mine dust management, When the dust concentration exceeds the set standard, the coal shearer and road header can automatically carry out high-pressure spraying to reduce dust. Compared with the traditional technology, the dust removal efficiency is increased by more than 80%.

Here, we report a new enhanced extrinsic pseudocapacitve Li-ion storage mechanism via lithiation-induced structural optimization strategy. The flower-like C@SnS and bulk SnS exhibit initial capacity decay and subsequent increase of capacity on cycling. After a long-term lithiation/delithiation process, flower-like C@SnS and bulk SnS exhibit improved rate performance and reversible capacity in comparison with those of initial state. Moreover, a high capacity of 530 mAh g −1 is still remained even after 1550 cycles at a high current density of 5.0 A g −1 for flower-like C@SnS after pre-lithiation of 350 cycles. According to the comprehensive analysis of structural evolution and electrochemical performance, it demonstrates that SnS electrodes experience crystal size reduction and further amorphization on cycling, which enhances the reversibility of conversion reaction for SnS, leading to increasing capacity. On the other hand, surface-dominated extrinsic pseudocapacitive contribution results in enhanced rate performance because electrodes expose a large fraction of Li + sites on surface or near-surface region with structural optimization on cycling. This study reveals that extrinsic pseudocapacitance of SnS can be stimulated via lithiation-induced structural optimization, which gives rise to high-rate and long-lived performances.

Enhancing the conductivity of electrode materials is critically important for improving the high-rate performance of Na-ion batteries (NIBs). Herein, we report a multifaceted strategy for optimizing the conductivity and electrochemical properties of nickel cobalt selenides via the combination of fine component regulation and C coating. The electrical conductivity of C@Ni0.33Co0.67Se2/C nanofiber (CNF) (Co0.67) hybrids achieved in this study was 0.3733 S mm−1, a conductivity five-fold higher than that of selenides with a Ni/Co ratio of 2 : 1. Coupled with desirable three-dimensional (3D) nanobrush morphology and the 1D conducting path of CNFs, the Co0.67 electrode achieved a superior rate performance of 413.1 mA h g−1, even at 2 A g−1. Furthermore, the Co0.67 electrode exhibited an impressive cycling performance of 499 mA h g−1 after 100 cycles (exhibiting an 89.5% capacity retention of the second cycle). Finally, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry analysis at different sweep rates were conducted to demonstrate the Co0.67 electrode's fast charge/ion transport ability and increased electrode kinetics.

In this article, tufted NiCo 2 O 4 nanoneedles directly grown on carbon nanofibers (CNFs) were successfully fabricated by a facile hydrothermal procedure and subsequent annealing. The morphology of tufted NiCo 2 O 4 nanoneedles/carbon nanofibers (TNN/CNFs) composite appears like clustered acicular leaves on branches, forming a unique three dimensional (3D) hybrid structure. Compared to NiCo 2 O 4 nanoneedles spheres (NNS) without CNFs, the TNN/CNFs material presents a reversible discharge specific capacity up to 1033.6 mAh g −1 at a current density of 200 mA g −1 even after 250 cycles, with the coulombic efficiency of above 98%. The unique 3D hybrid structure formed with CNFs should be responsible for the superior lithium storage capacity and enhanced cycling performance, which provides short distance for ions transport, high specific surface area for large contact areas between electrode and electrolyte, together with the interspace to accommodate volume change and smaller agglomeration tendency. Moreover, the design route proposed offers more possibility to preparation of high-performance anode materials for LIBs.

Carbon coated SnS/SnO2 heterostructures wrapping on carbon nanofibers (C@SnS/SnO2@CNFs) was demonstrated to have excellent performance as an anode material for Li-ion batteries. C@SnS/SnO2@CNFs electrode delivers high reversible capacity of 826.8 mA h g–1 (500th cycle) at the current density of 1.0 A g–1. However, an interesting phenomenon of increasing capacity on cycling can be observed. According to the analysis of the evolution of structure and electrochemical property, C@SnS/SnO2@CNFs is demonstrated to experience the progress of conversion from nanowalls containing polycrystals into amorphous nanosheets with high porosity and larger surface upon cycling. The above lithiation-induced structural optimization provides larger effective surface areas and encourages the conversion reactions, which can promote charge transfer and also enhance the reversibility of the conversion reactions of SnS and SnO2 inducing the increasing reversible capacity. The study explains the progress of increasing capacity of C...

Grape seed proanthocyanidin (GSPA) consists of catechin, epicatechin and epicatechin gallate, which are strong antioxidants that are beneficial to health and may attenuate or prevent Alzheimer's disease (AD). In the present study, the effects of GSPA on pheochromocytoma (PC12) cell viability were determined using cell counting kit-8 and lactate dehydrogenase (LDH) assays, whereas apoptosis and mitochondrial membrane potential (Ψm) were measured via flow cytometry analysis. The effect of GSPA administration on the behavior and memory of amyloid precursor protein (APP)/presenilin-1 (PS-1) double transgenic mice was assessed using a Morris water maze. APP Aβ peptides and tau hyperphosphorylation were examined by western blotting; whereas the expression levels of PS-1 were evaluated by reverse transcription-quantitative polymerase chain reaction and compared with pathological sections stained with hematoxylin-eosin and Congo red. Data from the in vitro experiments demonstrated that GSPA significantly alleviated Aβ25-35 cytotoxicity and LDH leakage ratio, inhibited apoptosis and increased Ψm. The findings from the in vivo experiments showed a significant enhancement in cognition and spatial memory ability, an improvement in the pathology of APP and tau protein and a decrease in PS-1 mRNA expression levels. Therefore, the results of the present study indicated that GSPA may be a novel therapeutic strategy for the treatment of AD or may, at the very least, improve the quality of life of patients with AD.

A novel heterostructured cathode material, comprised of a core of Li-rich layered (Rm) oxides integrated with Li+-conductive Li2SiO3 and an in situ formed spinel (Fdm) nano-coating layer, has been successfully synthesized. The ionic conductor Li2SiO3 in the bulk facilitates the Li+ intercalation/deintercalation process and stabilizes the layered structure. This is coupled with the fast 3D Li+ diffusion channels of an electrochemically active spinel coating layer, leading to superior rate capability (94 mA h g−1 at 10C) and excellent cycling stability in the heterostructured cathode material. This synergistic strategy may provide some new directions for synthesizing high-performance Li-ion battery cathode materials.

Carbon coated SnS/SnO

Grape seed proanthocyanidin (GSPA) consists of catechin, epicatechin and epicatechin gallate, which are strong antioxidants that are beneficial to health and may attenuate or prevent Alzheimer's disease (AD). In the present study, the effects of GSPA on pheochromocytoma (PC12) cell viability were determined using cell counting kit-8 and lactate dehydrogenase (LDH) assays, whereas apoptosis and mitochondrial membrane potential (Ψm) were measured via flow cytometry analysis. The effect of GSPA administration on the behavior and memory of amyloid precursor protein (APP)/presenilin-1 (PS-1) double transgenic mice was assessed using a Morris water maze. APP Aβ peptides and tau hyperphosphorylation were examined by western blotting; whereas the expression levels of PS-1 were evaluated by reverse transcription-quantitative polymerase chain reaction and compared with pathological sections stained with hematoxylin-eosin and Congo red. Data from the in vitro experiments demonstrated that GSPA significantly alleviated Aβ25–35 cytotoxicity and LDH leakage ratio, inhibited apoptosis and increased Ψm. The findings from the in vivo experiments showed a significant enhancement in cognition and spatial memory ability, an improvement in the pathology of APP and tau protein and a decrease in PS-1 mRNA expression levels. Therefore, the results of the present study indicated that GSPA may be a novel therapeutic strategy for the treatment of AD or may, at the very least, improve the quality of life of patients with AD.

The chemical characterization of SQW. (PDF 295 kb)

A Chinese article about Suoquan Wan combined with Solifenacin Succinate on overactive. (PDF 139 kb)

Background Suo Quan Wan (SQW) is a Chinese traditional prescription that has been used in clinical treatment of lower urinary tract symptoms for centuries. However, scientific basis of SQW efficacy and mechanism is still needed. This study investigated the effect of SQW on bladder function and transient receptor potential vanilloid 1 (TRPV1) expression in the bladder of rats with bladder outlet obstruction (BOO). The induced changes in bladder function in overactive bladder (OAB) rat model were observed following different periods of outlet obstruction to obtain an appropriate rat model. Methods This study was carried out in two parts. In the first part, female Sprague–Dawley rats received sham operations or partial BOO operations. Two, four, and six weeks later, the OAB model groups and control were subjected to urodynamic tests to measure differences in bladder functions. Once the appropriate rat model was obtained, the second part of the experiment was performed. The rat model was recreated and treated with SQW. Urodynamic assessment was conducted, and the bladders of the rats were then removed. Immunofluorescence staining, real-time PCR, and Western blot were performed to localize and quantify the expression of TRPV1 in the bladder. Results Results of the first part indicated that at 2 and 4 weeks, the OAB model group exhibited significant differences in urodynamic parameters, including bladder pressure, maximum voiding pressure, and maximum bladder capacity, compared with the sham group. At 4 and 6 weeks, the OAB model group exhibited significant differences in residual volume (RV) and non-voiding contraction frequency. Six-week OAB model group showed much more RV but less voiding efficiency when compared with 6-week sham group or 2—and 4-week OAB model group. Rats that underwent BOO exhibited similarities with the compensated state before four weeks and may have entered decompensated state at six weeks. Studies conducted with 4-week OAB model were appropriate. In part two of the experiment, unstable bladder in the OAB model group recovered bladder stability after SQW treatment, accompanied by improved bladder hypertrophy, as well as corrected urodynamic parameters. Expression of TRPV1 mRNA and proteins in the bladder was significantly greater in the OAB model group than that in the control group, which subsequently decreased significantly with SQW treatment in BOO-induced rats. Conclusions SQW can modulate the expression of TRPV1 in accordance with the recovery of bladder function. Electronic supplementary material The online version of this article (doi:10.1186/s12906-015-0898-7) contains supplementary material, which is available to authorized users.