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study ON MESO-MECHANICAL SIMULATION OF GROUTING FOR UNFAVORABLE GEOLOGICAL CONDITIONS

工程力学 2023年第S01期40卷 248-258页

作者：秦鹏飞钟宏伟刘坚 Department of Engineering Huanghe University of Science and TechnologyZhengzhou 451000China Key Laboratory of Geotechnical Mechanics and Dam Engineering of the Ministry of Education Hohai UniversityNanjing 370000China School of Railway Engineering Zhengzhou Railway Vocational and Technical CollegeZhengzhou 451000China

The numerical simulation program of PFC2D(Particle Flow Code in 2 Dimension)particle flow based on the flow-solid coupling principle and,on its built-in FISHTANK function library and FISH language,defines the flow equation and pressure equation of fluid domain respectively,and carries out numerical simulation calculations on the diffusion process and,on the morphology and particle displacement of slurry during the slurry injection process.By adjusting the parameters of hist,n_bond,s_bond and measure in the PFC command flow,the tracking of granular body displacement changes is achieved,and the mesoscopic mechanism such as the diffusion law of soil slurry at different depths and the change of formation porosity is revealed.The numerical calculations show that:the grouting pressure has a significant effect on the alteration and destruction of the formation structure,and the fracturing effect becomes gradually worse with increasing adhesive strength,while the porosity increases significantly with increasing grouting pressure.Based on the elastic-plastic theory of the Mohr-Colomb criterion to theoretically derive the stress field of the soil around the borehole,it is pointed out that the mechanical mechanism of annular tension and radial compression is the fundamental reason for the appearance of fracturing grouting action mode.The increase of slurry viscosity is beneficial to improve the grouting effect of fracturing-compacting grouting,while the increase of friction coefficient has little effect on the grouting effect.The comparative analysis of the laboratory tests shows that the PFC2D simulation of the grouting process is feasible.

关键词： formation grouting particle flow numerical simulation meso-analysis slurry diffusion study soil foundation mechanics calculation

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study of effective parameters for enhancement of methane gas production from natural gas hydrate reservoirs

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Green Energy & Environment 2019年第4期4卷 453-469页

作者： Hamid Aghajari Moien Habibi Moghaddam Mehdi Zallaghi Azad University Omidiyeh BranchIran Isfahan Oil Refinery Co. Iran Science and Research Azad University of Tehran Iran Tehran Petroleum Research Center Petroleum University of TechnologyIran

Natural gas hydrate resources have become the major source of energy in the second half of 21st century.Gas production and fluid behavior in natural gas hydrate reservoirs are different from conventional ones.There are three major methods for methane decomposition such as depressurization,thermal stimulation and inhibitor injection.However,CO2 substitution can also be introduced as an alternative method to inject in sediments containing gas hydrate.All these methods tend to imbalance equilibrium condition via temperature and pressure variation in order to fulfill hydrate decomposition process.This study aims to simulate depressurization method for gas production from a hydrate gas bearing layer.Hence,a sensitivity analysis of reservoir parameters includes porosity,permeability,hydrate saturation,hydrate thickness layer;pressure and temperature of single well hydrate model were investigated to determine how these parameters impact on gas production.Results show that depressurization is an efficient method for gas production from hydrate bearing sediments.Through sensitivity analysis,it has been concluded that if properties of a hydrate layer such as porosity and permeability become greater,methane production will be increased significantly.Moreover,results investigate that the rate of hydrate dissociate is strongly dependent on pressure reduction,and it has a reverse relationship with bottomhole pressure and reservoir temperature.

关键词： Gas hydrate Depressurization Sensitivity analysis Simulation study Hydrate dissociation Methane formation Thermodynamic equilibrium

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study on covering rough sets with topological methods

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CAAI Transactions on Intelligence Technology 2019年第3期4卷 129-134页

作者： Xue Wang Liwen Ma School of Science Beijing University of Posts and TelecommunicationsBeijing 100876People’s Republic of China

The authors study the covering rough sets by topological methods. They combine the covering rough sets and topological spaces by means of defining some new types of spaces called covering rough topological (CRT) spaces based on neighbourhoods or complementary neighbourhoods. As the separation axioms play a fundamental role in general topology, they introduce all these axioms into covering rough set theories and thoroughly study the equivalent conditions for every separation axiom in several CRT spaces. They also investigate the relationships between the separation axioms in these special spaces and reveal these relationships through diagrams in different CRT spaces.

关键词： study on covering rough sets topological methods different CRT spaces

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Density functional and experimental study of NO/O2 on zigzag char

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Journal of Environmental Sciences 2020年第2期32卷 283-291页

作者： Jun Shen Hai Zhang Jiaxun Liu Lei Luo Sha Wang Bin Chen Xiumin Jiang School of Mechanical and Automotive Engineering Shanghai University of Engineering and ScienceShanghai 201620China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

In this paper, quantum chemistry computation(density functional theory) of multi-airstaged combustion was investigated in combination with experiment.It was found that the presence of oxygen in the combustion environment has a great influence on the surface chemistry of coal char.In the reaction pathway, the ring-opening reaction happens first,and is followed by NO adsorption.Afterwards, the ring-closure reaction takes place, leaving the nitrogen atom trapped in the inner char molecule.This reaction route effectively inhibits NO formation and achieves the aim of controlling NO emissions.In the staged combustion experiments, the consumption of O2/NO was accompanied by an increase in the CO2 concentration.The quantum chemistry computation successfully interprets the recent experimental trends displayed in multi-air-staged combustion.

关键词： Nitrogen oxide DFT study Coal combustion Heterogeneous reduction Char nitrogen

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study on risk factors of extrapyramidal symptoms induced by antipsychotics and its correlation with symptoms of schizophrenia

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General Psychiatry 2019年第1期32卷 14-21页

作者： Jiajun Weng Yan Zhang Huafang Li Yifeng Shen Wenjuan Yu Drug Clinical Trial Institution Shanghai Mental Health CenterShanghaiChina Psychiatry Shanghai Mental Health CenterShanghaiChina

Background Extrapyramidal symptoms (EPS) are one of the most common and neglected side effects during the treatment of schizophrenia. The risk factors of EPS in Chinese patients with schizophrenia and its relationship with psychiatric symptoms and mood symptoms of schizophrenia remain unknown. Aims The main objective of this study is to explore the risk factors of EPS caused by antipsychotics and the relationship between EPS and psychotic symptoms and mood symptoms of schizophrenia. Method This study included 679 patients with schizophrenia who have met the diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorders- Fourth Edition. Patients were divided into the EPS group and the non-EPS group according to the scale rating criteria and whether the anticholinergics have been used. The differences between demographic data and characters of drug intake were compared between the two groups, and the risk factors of EPS were selected between those factors. Correlation analysis was performed on the severity of schizophrenia (Positive and Negative Symptoms Scale (PANSS), Calgary Depression Scale for Schizophrenia (CDSS) score) and EPS scale (Simpson-Angus Scale (SAS), Barnes Akathisia Rating Scale (BARS), Abnormal Involuntary Movement Scale (AIMS) score) in 679 patients. The differences between the PANSS subscale score and the CDSS score between the EPS grong and the non-EPS group were compared. Result Compared with the non-EPS group, the EPS group patients are older, and they have a longer duration since first prescribed antipsychotics. The EPS group patients have higher frequency of atypical antipsychotics polytherapy and typical and atypical antipsychotics polytherapy or combined treatments with mood stabilisers. Logistic regression analysis shows that antipsychotics with high D2 receptor antagonistic effect and illness duration are the risk factors of EPS. The SAS score was significantly correlated with PANSS negative score, PANSS general psychopathological score and PANSS total score. The BARS

关键词： study risk factors extrapyramidal symptoms induced

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Prioritization of factors related to mental health of women during an earthquake:A qualitative study

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World Journal of Emergency Medicine 2019年第3期10卷 160-168页

作者： Rahele Samouei Shahin Shooshtari Masud Bahrami Mohammad Reza Abedi Mohammad Reza Maracy Social Determinants of Health Research Center Isfahan University of Medical Sciences Isfahan Iran Student Research Committee Isfahan University of Medical Sciences Isfahan Iran Department of Community Health Sciences Rady Faculty of Health Sciences University of Manitoba Winnipeg Manitoba Canada Nursing and Midwifery Care Research Center Faculty of Nursing and Midwifery Isfahan University of Medical Sciences Isfahan Iran Department of Counseling Faculty of Education and Psychology University of Isfahan Isfahan Iran Department of Epidemiology and Biostatistics Environment Research Center Research Institute for Primordial Prevention of Non-communicable Disease School of Public Health Isfahan University of Medical Sciences Isfahan Iran

BACKGROUND: According to the fact that women account for the highest rate of victims of mental health loss during disasters, prioritization of their requirements is of remarkable signifi cance. Therefore, the present study was carried out with the aim to prioritize factors related to women's mental health during an earthquake. METHODS: This study was conducted using the Delphi method in 2017. Participants consisted of experts including psychologists, counselors and psychiatrists, social medicine specialists, and psychiatric-mental health nurses with experience in service and disaster awareness, especially earthquake. They were selected using purposive and snowball sampling methods. The Delphi method was used in 2 rounds with 21 components and the fi nal attendance of 19 participants and the collective agreement of 75%. RESULTS: Of the 21 factors related to women's mental health during the earthquake, the following components were, respectively, preferred by the participants: psychological well-being training, group relationships and support of women in emergency situations, fair treatment in the provision of rights and services to women, crisis awareness and management of behavior and diffi cult conditions, and social security during disasters with the total mean standard deviation (SD) of 13.4 (2.4), 13.0 (2.4), 12.7 (2.5), 12.5 (2.4), and 12.3 (2.2), respectively. CONCLUSION: Training in the fi eld of psychology and disasters, and social and cultural factors were prioritized among factors related to women's mental health during an earthquake. Therefore, the results of this study can be applied by the planners and executives of mental health, women and disasters, and the women's community itself.

关键词： Mental health Women Earthquake Qualitative study

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Microvolt T-wave alternans complemented with electrophysiologic study for prediction of ventricular tachyarrhythmias in patients with arrhythmogenic right ventricular cardiomyopathy: a long-term follow-up study

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Chinese Medical Journal 2019年第12期132卷 1406-1413页

作者： She-Liang Xue Xiao-Feng Hou Kang-Yun Sun Yao Wang Zhi-Yong Qian Quan-Peng Wang Si-Peng Shen Hong-Li Yin Rong Zhang Hai-Ping Yin Jian-Gang Zou Department of Cardiology The First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu 210029China Department of Cardiology The Affiliated Wujin Hospital of Jiangsu UniversityChangzhouJiangsu 213002China Department of Cardiology The Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhouJiangsu 215008China Department of Biostatistics School of Public HealthNanjing Medical UniversityNanjingJiangsu 211166China Key Laboratory of Targeted Intervention in Cardiovascular Disease Collaborative Inn ovation Center for Cardiovascular Disease Translational MedicineNanjing Medical University NanjingJiangsu 211166China

Background: The long-term predicted value of microvolt T-wave alternans (MTWA) for ventricular tachyarrhythmia in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) remains unclear. Our study explored the characteristics of MTWA and its prognostic value when combined with an electrophysiologic study (EPS) in patients with ARVC. Methods: All patients underwent non-invasive MTWA examination with modified moving average (MMA) analysis and an EPS. A positive event was defined as the first occurrence of sudden cardiac death, documented sustained ventricular tachycardia (VT), ventricular fibrillation, or the administration of appropriate implantable cardioverter defibrillator therapy including shock or antitachycardia pacing. Results: Thirty-five patients with ARVC (age 38.6 ± 11.0 years;28 males) with preserved left ventricular (LV) function were recruited. The maximal TWA value (MaxValt) was 17.0 (11.0–27.0)μV. Sustained VT was induced in 22 patients by the EPS. During a median follow-up of 99.9 ± 7.7 months, 15 patients had positive clinical events. When inducible VT was combined with the MaxValt, the area under the curve improved from 0.739 to 0.797. The receiver operating characteristic curve showed that a MaxValt of 23.5 μV was the optimal cutoff value to identify positive events. The multivariate Cox regression model for survival showed that MTWA (MaxValt, hazard ratio [HR], 1.06;95% confidence interval [CI], 1.01–1.11;P = 0.01) and inducible VT (HR, 5.98;95% CI, 1.33–26.8;P = 0.01) independently predicted positive events in patients with ARVC. Conclusions: MTWA assessment with MMA analysis complemented by an EPS might provide improved prognostic ability in patients with ARVC with preserved LV function during long-term follow-up.

关键词： Modified moving average analysis Microvolt T-wave alternans Electrophysiologic study Ventricular tachyarrhythmia Arrhythmogenic right ventricular cardiomyopathy

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Effects of acupuncture in treating insomnia due to spleen-stomach disharmony syndrome and its influence on intestinal microbiome: study protocol for a randomized controlled trial

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Journal of Integrative Medicine 2019年第3期17卷 161-166页

作者： Ya-ru Huangfu Wei Peng Bao-jun Guo Zhi-fu Shen Li Li Shi-wei Liu Hui Zheng You-ping Hu Acupuncture and Tuina School Chengdu University of Traditional Chinese Medicine

Background: Insomnia is a common complaint that is closely related to gastrointestinal symptoms, which is consistent with the traditional Chinese medicine classical theory of ‘‘stomach disharmony leading to restless sleep." Acupuncture is an effective complementary and alternative medicine therapy to improve gastrointestinal function and restore the normal sleep-wake cycle. However, studies on the effectiveness of acupuncture for insomnia due to spleen-stomach disharmony syndrome are limited to case reports and few randomized controlled trials; deeper research on its mechanism is still lacking. This randomized controlled trial aims to assess the treatment efficacy of ‘‘harmonizing stomach to tranquilize mind"acupuncture for insomnia and its influence on the intestinal microbiome.Methods/design: This is a randomized, single-blind, parallel-group study. Sixty eligible patients with insomnia due to spleen-stomach disharmony syndrome will be randomly divided into two groups(1:1 allocation ratio). The intervention group will use ‘‘harmonizing stomach to tranquilize mind"acupuncture, and the control group will receive sham acupuncture. Participants will receive 5 acupuncture treatment sessions per week for 4 consecutive weeks. The Pittsburgh Sleep Quality Index will be used to evaluate the clinical efficacy of acupuncture treatment by making assessments at baseline, the end of treatment and the end of the follow-up. High-throughput 16 S ribosomal ribonucleic acid gene sequencing will be performed to detect changes in the intestinal microbial composition before and after treatment.Discussion: The results of this trial are expected to confirm that ‘‘harmonizing stomach to tranquilize mind" acupuncture can effectively relieve insomnia and alter the intestinal microbiome.

关键词： Insomnia Gastrointestinal symptoms Acupuncture Intestinal microbiome Randomized controlled trial study protocol

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Trajectories of mental health symptoms predict long-term quality of life among Wenchuan adolescent survivors:A 10-year follow-up study

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Chinese Journal of Traumatology 2021年第4期24卷 214-220页

作者： Zi-Juan Ma Xiao-Yan Chen Tong Wang Shu-Ling Xu Min Jiang Fang Fan School of Psychology Center for Studies of Psychological Applicationand Guangdong Key Laboratory of Mental Health and Cognitive ScienceSouth China Normal UniversityGuangzhou510631China Key Laboratory of Brain Cognition and Education SciencesMinistry of EducationChina

Purpose:Previous studies usually examine the associations between psychological distresses and quality of life(QOL)with a variable-centred approach,while little is known about the effect of the individual variance in time-varying changes of psychological distresses on QOL.Therefore,this study aimed to examine whether individual variance in psychological distresses during the early phases post-earthquake would develop different QOL’s levels among adolescent survivors 10-year after the Wenchuan earthquake.Methods:Data were extracted from the Wenchuan Earthquake Adolescent Health Cohort study.The current study included 744 adolescent survivors who effectively completed surveys at 6 months,24 months,and 10 years after the earthquake.Self-report questionnaires were administered to collect information on socio-demographic characteristics,earthquake exposure,life events,anxiety symptoms,depressive symptoms,posttraumatic stress symptoms(PTSS),and QOL.Data were analysed using hierarchical multiple regression.Results:Trajectories of psychological distresses were classified as follow:resistance(anxiety 40.73%;depression 54.70%;PTSS 74.46%),recovery(anxiety 17.20%;depression 9.27%;PTSS 10.35%),delayed dysfunction(anxiety 10.35%;depression 18.15%;PTSS 6.18%),and chronicity(anxiety 31.72%;depression 17.88%;PTSS 9.01%).After controlling covariates,hierarchical multiple regression only revealed that the anxiety trajectory with delayed dysfunction remained significantly predictive for four domains of QOL(physical health,psychological health,social relationships,and environment).Conclusion:The current study highlights the importance of focusing on the variations in trajectories of anxiety symptoms among disaster survivors and providing individualized mental health services to improve survivors’QOL.

关键词： Anxiety Depression Posttraumatic stress symptoms Quality of life Wenchuan earthquake Longitudinal study

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Kinetic study on photocatalytic degradation of Acid Orange 52 in a baffled reactor using TiO_2 nanoparticles

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Journal of Environmental Sciences 2019年第5期31卷 213-224页

作者： Payam Zanganeh Ranjbar Bita Ayati Hossein Ganjidoust Civil and Environmental Engineering Faculty Tarbiat Modares University

In this study, a baffled photocatalytic reactor was used for the treatment of colored wastewater containing the azo dye of Acid Orange 52(AO52). A study on the active species of the photocatalytic process using TiO_2 nanoparticles indicated that hydroxyl radical and superoxide have the greatest contribution to the dye degradation process respectively.Given that a level of biological oxygen demand/chemical oxygen demand(BOD5/COD) equal to 0.4 was achieved after about 5 hr from the beginning of the experiment, the reactor seems to be capable of purifying the wastewater containing AO52 dye after this time in order to discharge into a biological treatment system to continue the treatment process.The results of the liquid chromatography-mass spectrometry(LC-MS) test showed that during the first 4 hr of the experiment, with the breakdown of the azo bond, the contaminant was decomposed into the benzene annular compounds with less toxicity indicating a reduction in the toxicity of wastewater after removing the dye agent. The study on the kinetics of these reactions followed the pseudo-first-order kinetic model in all conditions and corresponded well to Langmuir–Hinshelwood model. According to the kinetic model for the simultaneous occurrence of possible pathways, the kinetic constant of production and degradation of intermediate products in optimal conditions was estimated to be between 0.0029 and 0.0391 min^(-1).

关键词： Kinetic study Active species Photocatalyst Decolorization

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