Damage Mechanism of Ultra-thin Asphalt Overlay(UTAO) based on Discrete Element Method

Aiming to analyze the damage mechanism of UTAO from the perspective of meso-mechanical mechanism using discrete element method(DEM),we conducted study of diseases problems of UTAO in several provinces in China,and found that aggregate spalling was one of the main disease types of UTAO.A discrete element model of UTAO pavement structure was constructed to explore the meso-mechanical mechanism of UTAO damage under the influence of layer thickness,gradation,and bonding modulus.The experimental results show that,as the thickness of UTAO decreasing,the maximum value and the mean value of the contact force between all aggregate particles gradually increase,which leads to aggregates more prone to spalling.Compared with OGFC-5 UTAO,AC-5 UTAO presents smaller maximum and average values of all contact forces,and the loading pressure in AC-5 UTAO is fully diffused in the lateral direction.In addition,the increment of pavement modulus strengthens the overall force of aggregate particles inside UTAO,resulting in aggregate particles peeling off more easily.The increase of bonding modulus changes the position where the maximum value of the tangential force appears,whereas has no effect on the normal force.

Optimization of a Pipeline-Type Savonius Hydraulic Turbine

This study focuses on a DN50 pipeline-type Savonius hydraulic turbine.The torque variation of the turbine in a rotation cycle is analyzed theoretically in the framework of the plane potential flow theory.Related numerical simulations show that the change in turbine torque is consistent with the theoretical analysis,with the main power zone and the secondary power zone exhibiting a positive torque.In contrast,the primary resistance zone and the secondary resistance zone are characterized by a negative torque.Analytical relationships between the turbine’s internal flow angleθ,the deflector’s inclination angleα0,and the coverage angleαof the power zone are introduced,and a method for calculating the optimal number of blades is proposed to maximize the power zone.Results are presented about performance tests conducted on five groups of hydraulic turbines with the blade number ranging from 3 to 7.Such results indicate that both the turbine’s recovery power and efficiency attain the highest values when the blade number is 4,which is in agreement with the number of blades calculated by the proposed method.Additionally,the study examines the effects of the flow rate on turbine parameters and the projected energy generation and cost savings for a specific pipeline configuration.

Intermittent fasting boosts antitumor immunity by restricting CD11b^(+)Ly6C^(low)Ly6G^(low) cell viability through glucose metabolism in murine breast tumor model

Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or immunotherapy.However,it is still uncertain how to select immunotherapy drugs to combine with intermittent fasting.Herein we observed that two cycles of fasting treatment significantly inhibited breast tumor growth and lung tissue metastasis,as well as prolonged overall survival in mice bearing 4T1 and 4T07 breast cancer.During this process,both the immunosuppressive monocytic-(M-)and granulocytic-(G-)myeloid-derived suppressor cell(MDSC)decreased,accompanied by an increase in interleukin(IL)7R^(+)and granzyme B^(+)T cells in the tumor microenvironment.Interestingly,we observed that Ly6G^(low)G-MDSC sharply decreased after fasting treatment,and the cell surface markers and protein mass spectrometry data showed potential therapeutic targets.Mechanistic investigation revealed that glucose metabolism restriction suppressed the splenic granulocytemonocyte progenitor and the generation of colony-stimulating factors and IL-6,which both contributed to the accumulation of G-MDSC.On the other hand,glucose metabolism restriction can directly induce the apoptosis of Ly6G^(low)G-MDSC,but not Ly6G^(high)subsets.In summary,these results suggest that glucose metabolism restriction induced by fasting treatment attenuates the immune-suppressive milieu and enhances the activation of CD3^(+)T cells,providing potential solutions for enhancing immune-based cancer interventions.

Spatiotemporal variations of ecosystem services and driving factors in the Tianchi Bogda Peak Natural Reserve of Xinjiang,China

Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,is an important ecological barrier area in the temperate arid zone.The evaluation of its important ecosystem services is of great significance to improve the management level and ecological protection efficiency of the reserve.In the present study,we assessed the spatiotemporal variations of four ecosystem services(including net primary productivity(NPP),water yield,soil conservation,and habitat quality)in the TBPNR from 2000 to 2020 based on the environmental and social data using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.In addition,the coldspot and hotspot areas of ecosystem services were identified by hotspot analysis,and the trade-off and synergistic relationships between ecosystem services were analyzed using factor analysis in a geographic detector.During the study period,NPP and soil conservation values in the reserve increased by 48.20%and 25.56%,respectively;conversely,water yield decreased by 16.56%,and there was no significant change in habitat quality.Spatially,both NPP and habitat quality values were higher in the northern part and lower in the southern part,whereas water yield showed an opposite trend.Correlation analysis revealed that NPP showed a synergistic relationship with habitat quality and soil conservation,and exhibited a trade-off relationship with water yield.Water yield and habitat quality also had a trade-off relationship.NPP and habitat quality were affected by annual average temperature and Normalized Difference Vegetation Index(NDVI),respectively,while water yield and soil conservation were more affected by digital elevation model(DEM).Therefore,attention should be paid to the spatial distribution and dynamics of trade-off and synergistic relationships between ecosystem services in future ecological management.The findings of the present study provide a reference that could facilitate the sustainable utilization of ecosystem services in the typical fragile areas of Northwest China.

Ballistic performance of spaced multi-ply soft fabrics: Experimental and numerical investigation

It has been reported that the ply gap influences the ballistic resistance of spaced multi-ply fabric systems,but its working mechanism was not well-understood. This paper reports the experimental and numerical approaches and results of an investigation on the mechanisms that enable the improved ballistic performance of spaced multi-ply systems. Penetration tests were performed over a range of impact velocities ranging from 200 m/s to 400 m/s. The results confirmed that the ply gap is beneficial to the energy absorption capability of the systems. This is because the front plies tend to absorb more energy when they are not immediately constrained by the rear plies. During a ballistic event, the gap relieves the reflection of the compressive pulse, prolonging the projectile engagement time with the front plies;on the other hand, the rear plies become increasingly less active in dissipating energy as the gap increases.When the gap is sufficiently widened to avoid any interference between the plies before the failure of the front ply, the responses of the whole system no longer vary. It was also found that the ballistic performance of the spaced systems is influenced by ply thickness, impact velocity, and the stacking order of the ply gap.

Dynamic analysis of major public health emergency transmission considering the dual-layer coupling of community–resident complex networks

We construct a dual-layer coupled complex network of communities and residents to represent the interconnected risk transmission network between communities and the disease transmission network among residents. It characterizes the process of infectious disease transmission among residents between communities through the SE2IHR model considering two types of infectors. By depicting a more fine-grained social structure and combining further simulation experiments, the study validates the crucial role of various prevention and control measures implemented by communities as primary executors in controlling the epidemic. Research shows that the geographical boundaries of communities and the social interaction patterns of residents have a significant impact on the spread of the epidemic, where early detection, isolation and treatment strategies at community level are essential for controlling the spread of the epidemic. In addition, the study explores the collaborative governance model and institutional advantages of communities and residents in epidemic prevention and control.

Residual Feature Attentional Fusion Network for Lightweight Chest CT Image Super-Resolution

The diagnosis of COVID-19 requires chest computed tomography(CT).High-resolution CT images can provide more diagnostic information to help doctors better diagnose the disease,so it is of clinical importance to study super-resolution(SR)algorithms applied to CT images to improve the reso-lution of CT images.However,most of the existing SR algorithms are studied based on natural images,which are not suitable for medical images;and most of these algorithms improve the reconstruction quality by increasing the network depth,which is not suitable for machines with limited resources.To alleviate these issues,we propose a residual feature attentional fusion network for lightweight chest CT image super-resolution(RFAFN).Specifically,we design a contextual feature extraction block(CFEB)that can extract CT image features more efficiently and accurately than ordinary residual blocks.In addition,we propose a feature-weighted cascading strategy(FWCS)based on attentional feature fusion blocks(AFFB)to utilize the high-frequency detail information extracted by CFEB as much as possible via selectively fusing adjacent level feature information.Finally,we suggest a global hierarchical feature fusion strategy(GHFFS),which can utilize the hierarchical features more effectively than dense concatenation by progressively aggregating the feature information at various levels.Numerous experiments show that our method performs better than most of the state-of-the-art(SOTA)methods on the COVID-19 chest CT dataset.In detail,the peak signal-to-noise ratio(PSNR)is 0.11 dB and 0.47 dB higher on CTtest1 and CTtest2 at×3 SR compared to the suboptimal method,but the number of parameters and multi-adds are reduced by 22K and 0.43G,respectively.Our method can better recover chest CT image quality with fewer computational resources and effectively assist in COVID-19.

Tumor microenvironment-responsive artesunate loaded Z-scheme heterostructures for synergistic photo-chemodynamic therapy of hypoxic tumor

Tumor microenvironment(TME)with the particular features of severe hypoxia,insufficient endogenous H2O2,and overexpression of glutathione(GSH)markedly reduced the antitumor efficacy of monotherapy.Herein,a TME-responsive multifunctional nanoplatform(Bi2S3@Bi@PDA-HA/Art NRs)was presented for synergistic photothermal therapy(PTT),chemodynamic therapy(CDT),and photodynamic therapy(PDT)to achieve better therapeutic outcomes.The Z-scheme heterostructured bismuth sulfide@bismuth nanorods(Bi2S3@Bi NRs)guaranteed excellent photothermal performance of the nanoplatform.Moreover,its ability to produce O2 and reactive oxygen species(ROS)synchronously could relieve tumor hypoxia and improve PDT outcomes.The densely coated polydopamine/ammonium bicarbonate(PDA/ABC)and hyaluronic acid(HA)layers on the surface of the nanoplatform enhanced the cancer-targeting capacity and induced the acidic TME-triggered in situ“bomb-like”release of Art.The CDT treatment was achieved by activating the released Art through intracellular Fe2+ions in an H2O2-independent manner.Furthermore,decreasing the glutathione peroxidase 4(GPX4)levels by Art could also increase the PDT efficiency of Bi2S3@Bi NRs.Owing to the synergistic effect,this nanoplatform displayed improved antitumor efficacy with minimal toxicity both in vitro and in vivo.Our design sheds light on the application of phototherapy combined with the traditional Chinese medicine monomer-artesunate in treating the hypoxic tumor.

Crosstalk between nano/micro particulate technologies and Chinese medicine: a bibliometric analysis

Background:Chinese medicine is widely applied in Asian and Western countries for its outstanding therapeutic effect,but there are still unsolved problems such as unclear active ingredients and pharmacological effects.The application of nano/microparticle technology in Chinese medicine may become a promising strategy to solve this problem in the near future(provided that more efforts are made to in-depth exploration).In this work,a comprehensive analysis of the field was carried out from a bibliometrics perspective,and further the publishing trends and research hotspots were figured out.Methods:The articles or reviews from 2000 to 2020 were retrieved in the database of Web of Science Core Collection.The documents were processed by Clarivate Analytic,Visualization of Similarities viewer,Statistical Analysis Toolkit for Informetrics and bibliometric online platform,and the data were visualized.Finally,a bibliometric summary,citation analysis results and research trends were described.Results:A bibliometric analysis of 773 articles of interest showed that research in this field had continued to grow in recent years,with a high degree of interdisciplinary integration.Secondly,this field attached great importance to the quantitative analysis of Chinese medicine combined with nano/micro particle technology.Chinese medicine,nanoparticles and liposomes were the most accessed keywords.China was the main contributing country,and the top-10 contributing organizations were all located in China.Co-authorship was a common phenomenon in this field.Conclusion:The published literature on the application of nano/micro particle technology in Chinese medicine was summarized.The results suggested that bibliometric analysis could predict possible directions for future research in this field.

Alleviating effects and mechanisms of action of large-leaf yellow tea drinking on diabetes and diabetic nephropathy in mice

Our previous study found that large-leaf yellow tea(LYT)had interesting hypoglycemic activity in high-fat diet-induced obese mice and highly safety in healthy mice. To study the anti-diabetic potential of LYT, the present study further investigated the preventive effects and mechanisms of action of LYT administration on diabetes and diabetic nephropathy in high-fat diet plus streptozotocin-induced diabetic mice. Results showed that LYT infusions(1/100 and 1/50, m/V)as drinking fluid for 4 weeks reduced diabetic polydipsia and polyuria, enhanced glucose tolerance and insulin sensitivity, and lowered fasting blood glucose level. The underlying mechanisms involve downregulation of gluconeogenesis(lower protein levels of TXNIP and FBP and enzyme activity of FBP), upregulation of lipid catabolism(higher protein levels of CPT-1α and PPARα), downregulation of lipogenesis(lower protein level of SREBP-1), and modification of the structure and abundance of gut microbiota to modulate metabolic homeostasis. Moreover, LYT administration prevented diabetic nephropathy, possibly due to reduced glucose-caused osmotic diuresis and lowered levels of renal PKC-β2, NLRP3 as well as membrane PKC-α, AQP2 and glycosylated AQP2 proteins. Taken together, LYT exhibits the activities in alleviating diabetic symptoms, ameliorating glucose and lipid dysmetabolism and fatty liver, and preventing diabetic nephropathy in diabetic mice. These activities may be explored for the prevention and treatment of diabetes in humans.

A Rational Design of Metal–Organic Framework Nanozyme with High‑Performance Copper Active Centers for Alleviating Chemical Corneal Burns

Metal–organic frameworks(MOFs)have attracted significant research interest in biomimetic catalysis.However,the modulation of the activity of MOFs by precisely tuning the coordination of metal nodes is still a significant challenge.Inspired by metalloenzymes with well-defined coordination structures,a series of MOFs containing halogen-coordinated copper nodes(Cu-X MOFs,X=Cl,Br,I)are employed to elucidate their structure–activity relationship.Intriguingly,experimental and theoretical results strongly support that precisely tuning the coordination of halogen atoms directly regulates the enzyme-like activities of Cu-X MOFs by influencing the spatial configuration and electronic structure of the Cu active center.The optimal Cu–Cl MOF exhibits excellent superoxide dismutase-like activity with a specific activity one order of magnitude higher than the reported Cu-based nanozymes.More importantly,by performing enzyme-mimicking catalysis,the Cu–Cl MOF nanozyme can significantly scavenge reactive oxygen species and alleviate oxidative stress,thus effectively relieving ocular chemical burns.Mechanistically,the antioxidant and antiapoptotic properties of Cu–Cl MOF are achieved by regulating the NRF2 and JNK or P38 MAPK pathways.Our work provides a novel way to refine MOF nanozymes by directly engineering the coordination microenvironment and,more significantly,demonstrating their potential therapeutic effect in ophthalmic disease.

Distribution Properties of Internal Air Voids in Ultrathin Asphalt Friction Course

The distribution characteristics of air voids in ultrathin asphalt friction course(UAFC) samples with different gradations and compaction methods were statistically analyzed using X-ray computed tomography(CT) and image analysis techniques. Based on the results, compared with the AC-5 sample, the OGFC-5mixture has a higher air void ratio, a larger air void size and a greater number of air voids, with the distribution of internal air voids being more uniform and their shapes being more rounded. The two-parameter Weibull function was applied to fit the gradation of air voids. The fitting results is good, and the function parameters are sensitive to changes in both mineral gradation and compaction method. Moreover, two homogeneity indices were proposed to evaluate the compaction uniformity of UAFC samples. Compared with the Marshall method,the SGC method is more conducive to improve the compaction uniformity of UAFC samples. The compaction method significantly influences the air void distribution characteristics and compaction uniformity of AC-5sample, but has a less significant impact on OGFC-5 sample. The experimental results in the study provides a solid foundation for further explorations on the internal structure and mixture design of UAFC.

Qualitative Exploration and Correction Strategies of the Criminal Psychological Mechanism of the Burglars

In order to explore the criminal psychological mechanism of burglars,this study adopts the qualitative research method of grounded theory to conduct in-depth interviews with 41 burglars in two prisons in Jiangxi Province,China.Nvivo 11.0 was used to code-construct and qualitatively analyze the interview content in order to refine the influencing factors and psychological evolution process of burglary behavior.Thefindings revealed that(1)burglary risk factors include burglary cognition,burglary motivation,burglary decision-making,delinquent peers,burglary opportunity,and incomplete reformation.(2)There are three stages in the psychological evolution pro-cess of burglars:cognitive formation,motivational dominance,and behavioral decision.(3)The interpretation of the criminal psychological mechanism of burglars is a comprehensive and dynamic outcome of the interaction of internal and external factors that shape the individual.Participants’inspection and non-participants’inspection were adapted to verify the research results’validity,which showed that the results were reliable.

Reabsorption of intervertebral disc prolapse after conservative treatment with traditional Chinese medicine:A case report

BACKGROUND Conservative treatments have been reported to diminish or resolve clinical symptoms of lumbar intervertebral disc herniation(LIDH)within a few weeks.CASE SUMMARY Computed tomography and magnetic resonance imaging(MRI)of the lumbar region of a 25-yearold male diagnosed with LIDH showed prolapse of the L5/S2 disc.The disc extended 1.0 cm beyond the vertebral edge and hung along the posterior vertebral edge.The patient elected a conservative treatment regimen that included traditional Chinese medicine(TCM),acupuncture,and massage.During a follow-up period of more than 12 mo,good improvement in pain was reported without complications.MRI of the lumbar region after 12 mo showed obvious reabsorption of the herniation.CONCLUSION A conservative treatment regimen of TCM,acupuncture,and massage promoted reabsorption of a prolapsed disc.

Resolvin D1 Induces mTOR-independent and ATG5-dependent Autophagy in BV-2 Microglial Cells

Objective The activation state of microglia is known to occupy a central position in the pathophysiological process of cerebral inflammation.Autophagy is a catabolic process responsible for maintaining cellular homeostasis.In recent years,autophagy has been demonstrated to play an important role in neuroinflammation.Resolvin D1(RvD1)is a promising therapeutic mediator that has been shown to exert substantial anti-inflammatory and proresolving activities.However,whether RvD1-mediated resolution of inflammation in microglia is related to autophagy regulation needs further investigation.The present study aimed to explore the effect of RvD1 on microglial autophagy and its corresponding pathways.Methods Mouse microglial cells(BV-2)were cultured,treated with RvD1,and examined by Western blotting,confocal immunofluorescence microscopy,transmission electron microscopy,and flow cytometry.Results RvD1 promoted autophagy in both BV-2 cells and mouse primary microglia by favoring the maturation of autophagosomes and their fusion with lysosomes.Importantly,RvD1 had no significant effect on the activation of mammalian target of rapamycin(mTOR)signaling.Furthermore,RvD1-induced mTOR-independent autophagy was confirmed by observing reduced cytoplasmic calcium levels and suppressed calcium/calmodulin-dependent protein kinase II(CaMK II)activation.Moreover,by downregulating ATG5,the increased phagocytic activity induced by RvD1 was demonstrated to be tightly controlled by ATG5-dependent autophagy.Conclusion The present work identified a previously unreported mechanism responsible for the role of RvD1 in microglial autophagy,highlighting its therapeutic potential against neuroinflammation.

On the Principle of Consistency of Rights and Obligations in the Constitution of PRC

“The Fundamental Rights and obligations of Citizens”, the title of Chapter II of the current Constitution of PRC, and the stipulation that citizens must fulfill certain obligations while enjoying rights have triggered many debates. Considering the historical origin, constitutional philosophy, and the text and structure of the Constitution, the special provisions of the current Constitution are influenced by the principle of consistency of rights and obligations. The principle of consistency of rights and obligations in the Constitution is of complex connotation. Therefore, although the principle of consistency of rights and obligations effectively connects the public and private spheres, it ignores the diversity and differences of the interests and elements contained in the Constitution, the asymmetry of the normative status of fundamental rights and fundamental obligations,and the right of citizens to self-determination of personal interests.The principle of consistency of rights and obligations should be purposefully narrowed and concretized: In the context of public-private integration and risk society prevention, the principle of consistency of rights and obligations can be used as a supplement to the functional system of the Constitution;in the field of fundamental political obligations, the principle of consistency of rights and obligations should be in line with the requirements of the state to respect and protect human rights;in the field of fundamental social obligations, the exercise of fundamental rights by individuals is protected by the Constitution as long as they comply with the law and do not infringe upon the interests of the social community. The principle of the consistency of rights and obligations is only used as the negative constituents of the determination of rights and the basis for the effect against a third party of fundamental rights.

Cyclostationary Feature Detection Based Spectrum Sensing Algorithm under Complicated Electromagnetic Environment in Cognitive Radio Networks

This paper focuses on improving the detection performance of spectrum sensing in cognitive radio(CR) networks under complicated electromagnetic environment. Some existing fast spectrum sensing algorithms cannot get specific features of the licensed users'(LUs') signal, thus they cannot be applied in this situation without knowing the power of noise. On the other hand some algorithms that yield specific features are too complicated. In this paper, an algorithm based on the cyclostationary feature detection and theory of Hilbert transformation is proposed. Comparing with the conventional cyclostationary feature detection algorithm, this approach is more flexible i.e. it can flexibly change the computational complexity according to current electromagnetic environment by changing its sampling times and the step size of cyclic frequency. Results of simulation indicate that this approach can flexibly detect the feature of received signal and provide satisfactory detection performance compared to existing approaches in low Signal-to-noise Ratio(SNR) situations.

Down-regulation of extracellular signal-regulated kinase 1/2 activity in P-glycoprotein-mediated multidrug resistant hepatocellular carcinoma cells

AIM:To study the expression and phosphorylation of extracellular signal-regulated kinase(ERK)1 and ERK2 in multidrug resistant(MDR)hepatocellular carcinoma(HCC)cells.METHODS:MDR HCC cell lines,HepG2/adriamycin(ADM)and SMMC7721/ADM,were developed by exposing parental cells to stepwise increasing concentrations of ADM.MTT assay was used to determine drug sensitivity.Flow cytometry was employed to analyze cell cycle distribution and measure cell P-glycoprotein(P-gp)and multidrug resistant protein 1(MRP1)expression levels.ERK1 and ERK2 mRNA expression levels were measured by quantitative real-time PCR(QRTPCR).Expression and phosphorylation of ERK1 and ERK2 were analyzed by Western blot.SMMC7721/ADM were resistant not only to ADM,but also to multiple anticancer drugs.The P-gp expression was over 10-fold higher in HepG2/ADM cells than in HepG2 cells(8.92%±0.22%vs 0.88%±0.05%,P<0.001)and over 4-fold higher in SMMC7721/ADM cells than in SMMC7721 cells(7.37%±0.26%vs 1.74%±0.25%,P<0.001).However,the MRP1 expression was not significantly higher in HepG2/ADM and SMMC7721/ADM cells than in parental cells.In addition,the percentage of MDR HepG2/ADM and SMMC7721/ADM cells was significantly decreased in the G0/G1 phase and increased in the the S phase or G2/M phase.QRT-PCR analysis demonstrated that the ERK1 and ERK2 mRNA expression increased apparently in HepG2/ADM cells and decreased significantly in SMMC7721/ADM cells.Compared with the expression of parental cells,ERK1 and ERK2 protein expressions were markedly decreased in SMMC7721/ADM cells.However,ERK2 protein expression was markedly increased while ERK1 protein expression had no significant change in HepG2/ADM cells.Phosphorylation of ERK1 and ERK2 was markedly decreased in both HepG2/ADM and SMMC7721/ADM MDR cells.CONCLUSION:ERK1 and ERK2 activities are downregulated in P-gp-mediated MDR HCC cells.ERK1 or ERK2 might be a potential drug target for circumventing MDR HCC cells.

Research on the width of filling body in gob-side entry retaining with high-water materials

To determine the filling body's width along the gob-side remained roadway which is underneath the gob,the authors analyzed the interaction mechanism between the roof and the supporting body along the remained roadway, based on the elastic thin plate theory of the stope roof. The stress state and mechanical response of the filling body along the remained roadway were studied. Specifically, firstly, the supporting pressure of the coal pillar which is on one side of the gob-side remained roadway was deduced.Also, an equation that is used to calculate the width of the balance area in the stress limit state was acquired. Then, an equation that is used to calculate the roof cutting force on one side of the supporting body was obtained. By using FLAC3D, the authors investigated the displacement field and stress field response laws of rock masses around the roadway with different filling body's widths. The results show that with the filling body's width increasing, the supporting ability of the filling body increases.Meanwhile, the rock mass displacement around the roadway and the filling body deformation decrease.The better the filling body's supporting effect is, the higher the roof cutting force will be. When the filling body's width is larger than 3.0 m, its internal bearing ability becomes stable and the filling body's deformation became non-apparent. Finally, analysis shows that the filling body's width should be 2.5 m.Furthermore, the authors conducted field tests in the supply roadway 1204, using high-water materials and acquired expected outcomes.

Energy dissipation of coal and rock during damage and failure process based on EMR

The physical and mechanical change processes of coal and rock are closely related to energy transformation,and the destruction and failure of coal and rock is an instability phenomena driven by energy change.However,the energy change of large-scale coal rock in the mine site is hardly calculated accurately,making it difficult to monitor coal-rock systematic failure and collapse from the perspective of energy.By the energy dissipation EMR monitoring system,we studied the damage and failure of coal and rock with bursting liability from the energy dissipation point using the geophysical method-EMR,and explored the energy dissipation characteristics during uniaxial compression and their main influencing factors.The results show that under displacement-control loading mode,there are 2 types of energy dissipation trends for both coal and rock with bursting liability.The type Ⅰ trend is a steady increase one during the whole process,therein,the energy dissipation of rock samples is accelerated at the peak load.The type Ⅱ trend energy is a W-shaped fluctuating one containing 6 stages.Under load-control loading mode,there is one energy dissipation trend of shock downward-steady rise.Besides that,rock samples also present a trend of 4 stages.The energy dissipation characteristics of coal and rockduring loading failure process can be used as effective criteria to assess whether they are in a stable or destructive stage.The factors influencing energy dissipation in the loading failure process of coal and rock mainly include strength,homogeneity,and energy input efficiency.