The idea of a human community with a shared future was proposed by the Communist Party of China(CPC)Central Committee with Comrade Xi Jinping at its core for the future development of human beings to face up to the mo...The idea of a human community with a shared future was proposed by the Communist Party of China(CPC)Central Committee with Comrade Xi Jinping at its core for the future development of human beings to face up to the most important question in today's world:“What is happening to the world and what should we do?”It profoundly answers the question of the world,history,and the times.The theory of a human community with a shared future is an innovative theory with a multidimensional formation logic that guides humanity toward continually seeking common interests and values.This paper dives into the profound motivations behind building a human community with a shared future from historical,cultural,and practical dimensions and analyzes its epochal value from both domestic and international perspectives.This not only helps exert China's role in the international community,contributing Chinese strength to the construction of a peaceful,stable,and prosperous human society,but also enhances the influence of the idea of a human community with a shared future in the international community,accelerating the building of a human community with a shared future that considers the legitimate concerns of all countries,and aiding in solving the crises facing the world.展开更多
The development of clean and sustainable energy sources has received widespread interest in the past few decades due to the rolling energy demands while extenuating the rising tiers of greenhouse gases and environment...The development of clean and sustainable energy sources has received widespread interest in the past few decades due to the rolling energy demands while extenuating the rising tiers of greenhouse gases and environmental pollution.Due to their intermittent nature,these green and sustainable sources require appropriate energy storage systems.Amongst different energy storage technologies,electrochemical energy storage devices,particularly supercapacitors(SCs),have fascinated global attention for their utilization in electric vehicles,power supports,portable electronics,and many others application requiring electric energy devices for their operation.Thus,the growth of SCs in the commercial market has squeezed requirements,and further developments are obligatory for their effective industrialization.In the meantime,SCs also face technical complications and contests for their introduction in industrial settings because of their low energy density and high Levelized cost.The present study combines core strengths,weaknesses,opportunities,and threats(SWOT)analysis of SCs with new perspectives and recent ideas.The challenges and the future progressive prospects of SCs are also presented in detail.This review will afford consistent direction and new superhighways for the further development of SCs as standalone and complementary energy storage systems.展开更多
Figuring out rock strength plays essential roles in the sub ground mining activities,such as oil and gas well drilling and hydraulic fracturing,coal mining,tunneling,and other civil engineering scenarios.To help under...Figuring out rock strength plays essential roles in the sub ground mining activities,such as oil and gas well drilling and hydraulic fracturing,coal mining,tunneling,and other civil engineering scenarios.To help understand the effects of the mineralogical composition on evaluating the rock strength,this research tries to establish indirect prediction models of rock strength by specific input mineral contents for common sedimentary rocks.Using rock samples collected from the outcrops in the Sichuan Basin,uniaxial compression tests have been conducted to sandstone,carbonate,and shale cores.Combining with statistical analysis,the experimental data prove it true that the mineralogical composition can be utilized to predict the rock strength under specific conditions but the effects of mineralogical composition on the rock strength highly depend on the rock lithologies.According to the statistical analysis results,the predicted values of rock strengths by the mineral contents can get high accuracies in sandstone and carbonate rocks while no evidences can be found in shale rocks.The best indicator for predicting rock strength should be the quartz content for the sandstone rocks and the dolomite content for the carbonate rocks.Especially,to improve the evaluation accuracy,the rock strengths of sandstones can be obtained by substituting the mineral contents of quartz and clays,and those of carbonates can be calculated by the mineral contents of dolomite and calcite.Noticeably,the research data point out a significant contrast of quartz content in evaluating the rock strength of the sandstone rocks and the carbonate rocks.Increasing quartz content helps increase the sandstone strength but decrease the carbonate strength.As for shale rocks,no relationship exists between the rock strength and the mineralogical composition(e.g.,the clay fractions).To provide more evidences,detailed discussion also provides the readers more glances into the framework of the rock matrix,which can be further studied in the future.These findings can help understand the effects of mineralogical composition on the rock strengths,explain the contrasts in the rock strength of the responses to the same mineral content(e.g.,the quartz content),and provide another indirect method for evaluating the rock strength of common sedimentary rocks.展开更多
New-type magnesium alloy with prominent solubility and mechanical property lays foundation for preparing fracturing part in petroleum extraction.Herein,Mg-xZn-Zr-SiC alloy is prepared with casting strategy.Electrochem...New-type magnesium alloy with prominent solubility and mechanical property lays foundation for preparing fracturing part in petroleum extraction.Herein,Mg-xZn-Zr-SiC alloy is prepared with casting strategy.Electrochemical and compression tests are conducted to assess the feasibility as decomposable material.Morphology,composition,phase and distribution are characterized to investigate decomposition mechanism.Results indicate that floccule,substrate component and reticulate secondary phase are formed on as-prepared surface.Sample also acts out enhanced compression strength to maintain pressure and guarantee stability in dissolution process.Furthermore,as decomposition time and zinc content increase,couple corrosion intensifies,resulting in gradually enhanced decomposition rate.Rapid sample decomposition is mainly due to basal anode dissolution,micro particle exfoliation and poor decomposition resistance of corroding product.Such work shows profound significance in preparing new-type accessible alloy to ensure rapid dissolution of fracturing part and guarantee stable compression strength in oil-gas reservoir exploitation.展开更多
Suction caissons are widely used for anchoring floating platform and offshore wind turbines.Penetration of the suction caisson into the desired position under the combination of its self-weight and applied suction res...Suction caissons are widely used for anchoring floating platform and offshore wind turbines.Penetration of the suction caisson into the desired position under the combination of its self-weight and applied suction resulted from pumping out the encased water is integral to practical engineering.Model tests were carried out to investigate the suctionassisted installation of suction caissons in clay under various undrained shear strengths.It was found that there exists a critical penetration depth value.When the penetration depth is smaller than the critical value,the soil plug undrained shear strength is higher than intact clay(i.e.,clay prior to installation).However,when the penetration depth is greater than the critical penetration depth,the undrained shear strength of soil plug is lower than intact clay.The critical value decreases with the increasing consolidation time and undrained shear strength of clay.During suction-assisted installation,cracks occur around suction caissons.The installation way has little effect on the crack formation.The influence range(i.e.,the maximum distance between the crack and the suction caisson edge)was found to increase with the increasing friction coefficient of interface between the suction caisson wall and soil and decreases with the increasing soil undrained shear strength.In addition,the drained condition of the clay during installation is dominated by the caisson aspect ratio,the undrained shear strength and the friction coefficient between the caisson wall and clay.Equations to estimate the penetration resistance and the required suction to install the suction caisson are summarized.展开更多
Adverse childhood experiences(ACEs)can negatively affect mental health,whereas character strengths seem to be positively correlated with mental health.Detailed information on the history of ACEs among university stude...Adverse childhood experiences(ACEs)can negatively affect mental health,whereas character strengths seem to be positively correlated with mental health.Detailed information on the history of ACEs among university students in China and the extent which mental health is associated with ACEs and character strengths can contribute to the needed empirical evidence for relevant stakeholders.Objectives of this study are 1)to estimate the prevalence of ACEs among undergraduate students in Southern China;and 2)to assess the extent which mental health outcomes(positive growth,well-being,and depression)are associated with ACEs and character strengths among undergraduate students in Southern China.We conducted a self-administered survey amongfirst and second-year students at a university in Southern China and analyzed data using descriptive statistics and linear regression analyses.Among the 779 students who completed the questionnaire,283 were males,439 were females,and 57 did not indicate their gender.The prevalence of ACEs among the participants was 32.1%.History of ACEs was associated with lower positive growth score(Adjusted Beta=-0.20;95%CI=-0.37,-0.02;p=0.030)and lower well-being score(Adjusted Beta=-1.13;95%CI=-2.04,-0.23;p=0.014).Vitality domain of character strength was associated with all three mental health outcomes after adjusting for covariables(all p-values<0.001).Our studyfindings provide empirical evidence for stakeholders in university mental health.However,caveats regarding lack of temporality,selection bias,social desirability bias,and lack of generalizability should be considered in the interpretation of the studyfindings.展开更多
Background Despite high relapse rate among methamphetamine (MA) abusers, there still have been little empirical data to date detecting the risk factors related to craving and relapse from the perspective of MA abusers...Background Despite high relapse rate among methamphetamine (MA) abusers, there still have been little empirical data to date detecting the risk factors related to craving and relapse from the perspective of MA abusers. Therefore, the aim of this study was to use qualitative research methods exploring the strengths, weaknesses, opportunities and threat factors that could facilitate or impede individuals' abstinence in a real-life context from the perspectives of MA abusers. Aim To use qualitative research methods exploring the strengths, weaknesses, opportunities and threat factors relating to individuals' abstinence in a real-life context. Method Semistructured interviews were conducted with 32 MA abusers recruited in Shanghai guided by open-ended questions on narrating the real-life catalysts and inhibitors related to craving, initiation, relapse and abstinence. All data were transcribed verbatim and analysed using a strengths, weaknesses, opportunities and threats (SWOT) analysis. Results The results of the SWOT analysis revealed that contextual factors including peer influence, prevalence and availability of MA, familiar venue of MA use, discrimination, sexual behaviours, alcohol, emotional states and their attitudes towards smoking MA were important factors that contribute to reinitiation and relapse. Surveillance systems, antidrug social workers, vocational skills trainings, moving to another city and family responsibility might serve as counter measures targeti叩 those mentioned weaknesses and threats above. Conclusion This SWOT analysis highlights the complex nature of relapse. Comprehensive interventions strengtheni叩 coping skills such as virtual reality techniques are desperately needed to facilitate individuals1 sustained abstinence.展开更多
The dipole-length, dipole-velocity and dipole-acceleration absorption oscillator strengths for the 1s^22s-1s^2np (3 ≤ n ≤9) transitions of lithium-like systems from Z = 11 to 20 are calculated by using the energie...The dipole-length, dipole-velocity and dipole-acceleration absorption oscillator strengths for the 1s^22s-1s^2np (3 ≤ n ≤9) transitions of lithium-like systems from Z = 11 to 20 are calculated by using the energies and the multiconfiguration interaction wave functions obtained from a full core plus correlation method, in which relativistic and mass-polarization effects on the energy, as the first-order perturbation corrections, are included. The results of three forms are in good agreement with each other, and closely agree with the experimental data available in the literature. Based on the quantum defects obtained with quantum defect theory (QDT), the discrete oscillator strengths for the transitions from the ground state to highly excited states 1s^2np (n ≥ 10) and oscillator strength densities corresponding to the bound-free transitions are obtained for these ions.展开更多
Coronary artery calcium data and reporting system(CAC-DRS)is a recently introduced standardized reporting system for calcium scoring on computed tomography.CAC-DRS provides four risk categories(0,1,2 and 3)along with ...Coronary artery calcium data and reporting system(CAC-DRS)is a recently introduced standardized reporting system for calcium scoring on computed tomography.CAC-DRS provides four risk categories(0,1,2 and 3)along with treatment recommendations for each category.As with any other new reporting platform,CAC-DRS has both advantages and disadvantages.Improved communication,better clarity of details,organized management recommendations and utility in future research and education are the major strengths of CAC-DRS.It has many limitations such as questionable need for a new system,few missing components,use of a less accurate visual method and treatment suggestions based on expert opinion instead of clinical trials.In this contemporary review,we discuss the new reporting system CAC-DRS,its application,strengths and limitations and conclude with some remarks for the future.展开更多
The transition energies, E1 transitional oscillator strengths of the spin-allowed as well as the spin-forbidden and the corresponding transition rates, and complete M1, E2, M2 forbidden transition rates for 1s^(2), 1s...The transition energies, E1 transitional oscillator strengths of the spin-allowed as well as the spin-forbidden and the corresponding transition rates, and complete M1, E2, M2 forbidden transition rates for 1s^(2), 1s2s, and 1s2p states of He I, are investigated using the multi-configuration Dirac–Hartree–Fock method. In the subsequent relativistic configuration interaction computations, the Breit interaction and the QED effect are considered as perturbation, separately. Our transition energies, oscillator strengths, and transition rates are in good agreement with the experimental and other theoretical results. As a result, the QED effect is not important for helium atoms, however, the effect of the Breit interaction plays a significant role in the transition energies, the oscillator strengths and transition rates.展开更多
Adolescence is a crucial time period with especial vulnerability for development of mental health problems.Growing interest is focusing on the determinants of positive mental health in order to find the key concepts t...Adolescence is a crucial time period with especial vulnerability for development of mental health problems.Growing interest is focusing on the determinants of positive mental health in order to find the key concepts that could be influenced in the promotion of mental well-being of adolescents.In this study we aim to explore the relations between self-esteem,character strengths and experience of social inclusion as determinants of adolescents’positive mental health controlled for selected sociodemographic background factors.The study population(n=195)consisted of comprehensive school students who filled in an electronic questionnaire of adolescent’s mental well-being in Fall 2019.The questionnaire included measures of Warwick-Edinburgh Mental Well-being Scale(WEMWBS),VIA Youth-measure 96,Rosenberg Self-Esteem Scale and Experience of Social Inclusion Scale.The methods included group comparisons and General Linear Model computed by SPSS 24.0.The strongest association was found between positive mental health and self-esteem(β=0.789,p<0.001),followed by character strengths of hope and kindness and experience of social inclusion.Interestingly,family’s socioeconomic factors did not associate significantly with positive mental health in the final statistical model.In terms of our results,it seems that self-esteem,character strengths and experience of social inclusion might have stronger association with adolescents’mental well-being than family’s socioeconomic determinants.Therefore,it should be discussed whether psychological determinants overcome the individual effect of poor socioeconomic status as factors that influence positive mental health.Further studies are needed to establish these results more firmly.展开更多
The Strengths and Difficulties Questionnaire (SDQ) is a brief screening measure of emotional and behavioural difficulties in children and adolescents. The aim of this study was to assess reliability and validity of th...The Strengths and Difficulties Questionnaire (SDQ) is a brief screening measure of emotional and behavioural difficulties in children and adolescents. The aim of this study was to assess reliability and validity of the Greek version of the SDQ. A representative Greek sample of 1194 adolescents (aged 11 to 17 years) and their parents completed the SDQ along with other measures. Internal consistency reliability was determined by calculation of the Cronbach α coefficient. Varimax Orthogonal Transformation was conducted to test the factor structure of the questionnaire. Validity was further examined by investigating the correlation of the SDQ with the KIDSCREEN questionnaire and its association with demographic factors. The inter-rater agreement between parent and self-reports was analyzed with Pearson’s correlation coefficient. Intra-class correlation coefficients (ICCs) were computed to determine test-retest stability. For both parent and the self-report SDQ versions, most items loaded onto their predicted factors in consistency with the originally proposed five-factor structure. Internal consistency reliability was acceptable with a Cronbach α above 0.70 for all SDQ scales except for conduct and peer problems. Inter-rater correlations ranged from 0.33 to 0.45. Test-retest stability was good (ICCs > 0.60). Correlation coefficients between the SDQ and KIDSCREEN questionnaire were significant. Small effect sizes (d > 0.5) of the socioeconomic status were found for all of the SDQ scale mean scores. In conclusion, the SDQ was found to have satisfying psychometric properties and could be suitable for assessing emotional and behavioural problems in Greek adolescents.展开更多
The scattering matrices of e+N^(+)with J^(π)=1.5^(+)in discrete energy regions are calculated using the eigenchannel R-matrix method.We obtain good parameters of multichannel quantum defect theory(MQDT)that vary smoo...The scattering matrices of e+N^(+)with J^(π)=1.5^(+)in discrete energy regions are calculated using the eigenchannel R-matrix method.We obtain good parameters of multichannel quantum defect theory(MQDT)that vary smoothly as the function of the energy resulting from the analytical continuation property of the scattering matrices.By employing the MQDT,all discrete energy levels for N could be calculated accurately without missing anyone.The MQDT parameters(i.e.,scattering matrices)can be calibrated with the available precise spectroscopy values.In this work,the optical oscillator strengths for the transition between the ground state and Rydberg series are obtained,which provide rich data for the diagnostic analysis of plasma.展开更多
After the analysis of the value of rural tourism development in Suining City,the paper has pointed out that rural tourism development is an important content of Suining City accelerating economic development,a signifi...After the analysis of the value of rural tourism development in Suining City,the paper has pointed out that rural tourism development is an important content of Suining City accelerating economic development,a significant approach to promote social harmony and an innovation road to optimize industrial transformation.It has summarized the resources' districts and condition to develop rural tourism in Suining City.Based on "one center and four districts",the layout mode for Suining rural tourism development has been analyzed.It emphasizes that Suining rural tourism development should enhance publicity,integrate financing channels,pay attention to optimization of service quality,highlight environmental protection and insist on scientific development.展开更多
By performing density functional theory plus U calculations, we systematically study the structural, electronic, and magnetic properties of U02 under uniaxial tensile strain. The results show that the ideal tensile st...By performing density functional theory plus U calculations, we systematically study the structural, electronic, and magnetic properties of U02 under uniaxial tensile strain. The results show that the ideal tensile strengths along the [100], [110], and [111] directions are 93.6, 2Z7, and 16.4 GPa at strains of 0.44, 0.24, and 0.16, respectively. After electronic-structure investigation for tensile stain along the [001] direction, we find that the strong mixed ionic/covalent character of U-O bond is weakened by the tensile strain and there will occur an insulator to metal transition at strain over 0.30.展开更多
After fierce competition, Obama won the presidential race and was successfully elected as the firstAfrican-American President in US history. Unlike his predecessors, his success is primarily dependent on personalstrug...After fierce competition, Obama won the presidential race and was successfully elected as the firstAfrican-American President in US history. Unlike his predecessors, his success is primarily dependent on personalstruggle rather than renowned family background or remarkable personal political experience andaccomplishments; the change in US political environment reflected by the case is defined as "The ObamaPhenomenon". The Obama Phenomenon is the product of a variety of factors: The values of Individualism alongwith the philosophy of Pragmatism have built the macro-environment for it; Obama's elite political backgroundand his excellent personal strengths have laid the foundation for his success; the mistakes in domestic and foreignaffairs made by the Bush Administration made the Republican Party lose popular support, which removed theobstacles to Obama's success. This paper is to explore the reasons for Obama's success so as to contribute to abetter understanding of the changes in US society, in particular its political environment, excavate the impetus forthe changes, and rationally predict its展开更多
In this work numerical codes carried out in a multiconfiguration Har-tree-Fock relativistic (HFR) approach for the P IV ion are used to obtain the oscillator strengths of each transition as well as the lifetimes of ea...In this work numerical codes carried out in a multiconfiguration Har-tree-Fock relativistic (HFR) approach for the P IV ion are used to obtain the oscillator strengths of each transition as well as the lifetimes of each energy level. With the existing data from several authors that contributed to the spectrum using different light sources, and optimizing the electrostatic parameters by a least-squares procedure when replacing the theoretical values by the experimental ones in the energy matrices, one obtains closer values and according to the observations for the intensities, and also of the lifetimes closer to those that would be obtained experimentally.展开更多
Aim: This study determined whether prior brushing with desensitizing toothpastes (Sensodyne Rapid Relief and Colgate Pro-Relief) affected the shear bond strengths of composite to dentine surfaces after appropriate use...Aim: This study determined whether prior brushing with desensitizing toothpastes (Sensodyne Rapid Relief and Colgate Pro-Relief) affected the shear bond strengths of composite to dentine surfaces after appropriate use of two different dentine bonding agents (SingleBond and PQ-1). Materials and Methods: Sixty caries free molar teeth were cleaned, disinfected and embedded in individual cylinders of polymethylmethracyrlate. The occulsal surfaces were flattened to expose dentine and finished down with 600 grit silicone carbide paper. The teeth were randomly divided into six groups of 10 teeth each. Two groups served as control where dentine surfaces were brushed with pumice slurry. Of the remaining 4 groups, 2 groups were brushed with Sensodyne Rapid Relief and 2 groups brushed with Colgate Pro-Relief. The dentine surfaces were brushed to simulate 2 weeks of twice-daily toothpaste use. The specimens in each of the control groups and experimental groups were subjected to dentine bonding procedures (Single Bond or PQ-1), and application of hybrid composite resin (Z-250) according to the manufacturer’s instructions. A universal material testing machine, with a cross head speed of 0.05 mm/min was used to determine shear bond strengths. Results: Mean shear bond strengths ranged from 5.71 MPa (Colgate pretreatment, composite bonded with Single Bond) to 9.07 MPa (Sensodyne pretreatment, composite bonded with Single Bond). Results showed neither of the main effects, of toothpaste type or bonding agent were significant (p > 0.05) but their interaction was (F = 4.25, p = 0.02). Post hoc analysis showed that teeth brushed with the Sensodyne group, treated with the unfilled dentine bonding agent had a significantly higher bond strength than those treated with the filled dentine bonding agent. Conclusion: The desensitizing toothpastes that use the mechanism of occlusion of open dentinal tubules in the preliminary management of tooth sensitivity should not have an adverse effect on future restorative treatment modalities.展开更多
Energy levels, oscillator strengths, and transition probabilities, for the 1s2 2s2 2p6, 2p53l (l = 0, 1, 2), 2p54l (l = 0, 1, 2, 3) states in Ni XIX and Cu XX are calculated using COWAN code. The Correlation and relat...Energy levels, oscillator strengths, and transition probabilities, for the 1s2 2s2 2p6, 2p53l (l = 0, 1, 2), 2p54l (l = 0, 1, 2, 3) states in Ni XIX and Cu XX are calculated using COWAN code. The Correlation and relativistic effects are considered. The calculations are compared with other results in the literature. A good agreement is found. We also report on some unpublished energy values.展开更多
The belt and road initiative strategy is proposed based on the stable and sustainable cooperation on economy and development between China and neighboring countries.The development of economy can affect every aspect o...The belt and road initiative strategy is proposed based on the stable and sustainable cooperation on economy and development between China and neighboring countries.The development of economy can affect every aspect of vocational education development.Therefore,vocational education in China must be moved toward internationalization to achieve sustainable development in the face of the implementation of the belt and road initiative strategy.The analysis data obtained through the strengths,weaknesses,opportunities,and threats analysis method on the internationalization of China’s vocational education under the background of the belt and road initiative strategy were the advantages analysis(strengths)of continuous maturity in developing of vocational education,which drives by economic development and the foreign employment and entrepreneurship guidance mechanism;the disadvantages analysis(weaknesses)of lack talent cultivation and weak branding of vocational education;analysis of support opportunities given by national policy;and threats analysis of social culture in the involved countries along the route.To further develop and expand China’s vocational education under the background of the belt and road initiative strategy,some countermeasures were proposed such as improves cultivation or training of talents,to build strong branding of China vocational education,and faces cultural challenges to facilitate the international development of China vocational education.展开更多
文摘The idea of a human community with a shared future was proposed by the Communist Party of China(CPC)Central Committee with Comrade Xi Jinping at its core for the future development of human beings to face up to the most important question in today's world:“What is happening to the world and what should we do?”It profoundly answers the question of the world,history,and the times.The theory of a human community with a shared future is an innovative theory with a multidimensional formation logic that guides humanity toward continually seeking common interests and values.This paper dives into the profound motivations behind building a human community with a shared future from historical,cultural,and practical dimensions and analyzes its epochal value from both domestic and international perspectives.This not only helps exert China's role in the international community,contributing Chinese strength to the construction of a peaceful,stable,and prosperous human society,but also enhances the influence of the idea of a human community with a shared future in the international community,accelerating the building of a human community with a shared future that considers the legitimate concerns of all countries,and aiding in solving the crises facing the world.
基金supported by the Japan Society for the Promotion of Science(JSPS)KAKENHI Grant Number JP22F22368。
文摘The development of clean and sustainable energy sources has received widespread interest in the past few decades due to the rolling energy demands while extenuating the rising tiers of greenhouse gases and environmental pollution.Due to their intermittent nature,these green and sustainable sources require appropriate energy storage systems.Amongst different energy storage technologies,electrochemical energy storage devices,particularly supercapacitors(SCs),have fascinated global attention for their utilization in electric vehicles,power supports,portable electronics,and many others application requiring electric energy devices for their operation.Thus,the growth of SCs in the commercial market has squeezed requirements,and further developments are obligatory for their effective industrialization.In the meantime,SCs also face technical complications and contests for their introduction in industrial settings because of their low energy density and high Levelized cost.The present study combines core strengths,weaknesses,opportunities,and threats(SWOT)analysis of SCs with new perspectives and recent ideas.The challenges and the future progressive prospects of SCs are also presented in detail.This review will afford consistent direction and new superhighways for the further development of SCs as standalone and complementary energy storage systems.
基金supported by National Key Research and Development Program of China(2019YFA0708302)National Natural Science Foundation of China(Grant No.52004296,and Grant No.52274016)+1 种基金the Foundation of State Key Laboratory of Petroleum Resources and Prospecting(PRP/DX-2206)Science Foundation of China University of Petroleum-Beijing(No.2462022YXZZ007,No.2462022BJRC012).
文摘Figuring out rock strength plays essential roles in the sub ground mining activities,such as oil and gas well drilling and hydraulic fracturing,coal mining,tunneling,and other civil engineering scenarios.To help understand the effects of the mineralogical composition on evaluating the rock strength,this research tries to establish indirect prediction models of rock strength by specific input mineral contents for common sedimentary rocks.Using rock samples collected from the outcrops in the Sichuan Basin,uniaxial compression tests have been conducted to sandstone,carbonate,and shale cores.Combining with statistical analysis,the experimental data prove it true that the mineralogical composition can be utilized to predict the rock strength under specific conditions but the effects of mineralogical composition on the rock strength highly depend on the rock lithologies.According to the statistical analysis results,the predicted values of rock strengths by the mineral contents can get high accuracies in sandstone and carbonate rocks while no evidences can be found in shale rocks.The best indicator for predicting rock strength should be the quartz content for the sandstone rocks and the dolomite content for the carbonate rocks.Especially,to improve the evaluation accuracy,the rock strengths of sandstones can be obtained by substituting the mineral contents of quartz and clays,and those of carbonates can be calculated by the mineral contents of dolomite and calcite.Noticeably,the research data point out a significant contrast of quartz content in evaluating the rock strength of the sandstone rocks and the carbonate rocks.Increasing quartz content helps increase the sandstone strength but decrease the carbonate strength.As for shale rocks,no relationship exists between the rock strength and the mineralogical composition(e.g.,the clay fractions).To provide more evidences,detailed discussion also provides the readers more glances into the framework of the rock matrix,which can be further studied in the future.These findings can help understand the effects of mineralogical composition on the rock strengths,explain the contrasts in the rock strength of the responses to the same mineral content(e.g.,the quartz content),and provide another indirect method for evaluating the rock strength of common sedimentary rocks.
基金supported by the National Natural Science Foundation of China(No.51905417)China Postdoctoral Science Foundation(No.2020M670306).
文摘New-type magnesium alloy with prominent solubility and mechanical property lays foundation for preparing fracturing part in petroleum extraction.Herein,Mg-xZn-Zr-SiC alloy is prepared with casting strategy.Electrochemical and compression tests are conducted to assess the feasibility as decomposable material.Morphology,composition,phase and distribution are characterized to investigate decomposition mechanism.Results indicate that floccule,substrate component and reticulate secondary phase are formed on as-prepared surface.Sample also acts out enhanced compression strength to maintain pressure and guarantee stability in dissolution process.Furthermore,as decomposition time and zinc content increase,couple corrosion intensifies,resulting in gradually enhanced decomposition rate.Rapid sample decomposition is mainly due to basal anode dissolution,micro particle exfoliation and poor decomposition resistance of corroding product.Such work shows profound significance in preparing new-type accessible alloy to ensure rapid dissolution of fracturing part and guarantee stable compression strength in oil-gas reservoir exploitation.
基金financially supported by the National Natural Science Foundation of China (Grant Nos.52371301,51879044 and 51808325)the Shandong Natural Fund (Grant No.ZR2020QE258)。
文摘Suction caissons are widely used for anchoring floating platform and offshore wind turbines.Penetration of the suction caisson into the desired position under the combination of its self-weight and applied suction resulted from pumping out the encased water is integral to practical engineering.Model tests were carried out to investigate the suctionassisted installation of suction caissons in clay under various undrained shear strengths.It was found that there exists a critical penetration depth value.When the penetration depth is smaller than the critical value,the soil plug undrained shear strength is higher than intact clay(i.e.,clay prior to installation).However,when the penetration depth is greater than the critical penetration depth,the undrained shear strength of soil plug is lower than intact clay.The critical value decreases with the increasing consolidation time and undrained shear strength of clay.During suction-assisted installation,cracks occur around suction caissons.The installation way has little effect on the crack formation.The influence range(i.e.,the maximum distance between the crack and the suction caisson edge)was found to increase with the increasing friction coefficient of interface between the suction caisson wall and soil and decreases with the increasing soil undrained shear strength.In addition,the drained condition of the clay during installation is dominated by the caisson aspect ratio,the undrained shear strength and the friction coefficient between the caisson wall and clay.Equations to estimate the penetration resistance and the required suction to install the suction caisson are summarized.
基金funded by the Guangdong Provincial Philosophy and Social Science Planning Project(GD22XJY25).
文摘Adverse childhood experiences(ACEs)can negatively affect mental health,whereas character strengths seem to be positively correlated with mental health.Detailed information on the history of ACEs among university students in China and the extent which mental health is associated with ACEs and character strengths can contribute to the needed empirical evidence for relevant stakeholders.Objectives of this study are 1)to estimate the prevalence of ACEs among undergraduate students in Southern China;and 2)to assess the extent which mental health outcomes(positive growth,well-being,and depression)are associated with ACEs and character strengths among undergraduate students in Southern China.We conducted a self-administered survey amongfirst and second-year students at a university in Southern China and analyzed data using descriptive statistics and linear regression analyses.Among the 779 students who completed the questionnaire,283 were males,439 were females,and 57 did not indicate their gender.The prevalence of ACEs among the participants was 32.1%.History of ACEs was associated with lower positive growth score(Adjusted Beta=-0.20;95%CI=-0.37,-0.02;p=0.030)and lower well-being score(Adjusted Beta=-1.13;95%CI=-2.04,-0.23;p=0.014).Vitality domain of character strength was associated with all three mental health outcomes after adjusting for covariables(all p-values<0.001).Our studyfindings provide empirical evidence for stakeholders in university mental health.However,caveats regarding lack of temporality,selection bias,social desirability bias,and lack of generalizability should be considered in the interpretation of the studyfindings.
基金National Key R&D Program of China (2017YFC1310400), National Nature Science Foundation of China (U150222& 81501148)Shanghai Municipal Health and Family Planning Commission (2014ZYJB0002)+3 种基金Shanghai Health and Family Planni叩 Commission Clinical Research Project (20184Y0134)Program of Shanghai Academic Research Leader (17XD1403300)Shanghai Key Laboratory of Psychotic Disorders (13DZ2260500)Qihang Project of Shanghai Mental Health Center (2018-QH-02).
文摘Background Despite high relapse rate among methamphetamine (MA) abusers, there still have been little empirical data to date detecting the risk factors related to craving and relapse from the perspective of MA abusers. Therefore, the aim of this study was to use qualitative research methods exploring the strengths, weaknesses, opportunities and threat factors that could facilitate or impede individuals' abstinence in a real-life context from the perspectives of MA abusers. Aim To use qualitative research methods exploring the strengths, weaknesses, opportunities and threat factors relating to individuals' abstinence in a real-life context. Method Semistructured interviews were conducted with 32 MA abusers recruited in Shanghai guided by open-ended questions on narrating the real-life catalysts and inhibitors related to craving, initiation, relapse and abstinence. All data were transcribed verbatim and analysed using a strengths, weaknesses, opportunities and threats (SWOT) analysis. Results The results of the SWOT analysis revealed that contextual factors including peer influence, prevalence and availability of MA, familiar venue of MA use, discrimination, sexual behaviours, alcohol, emotional states and their attitudes towards smoking MA were important factors that contribute to reinitiation and relapse. Surveillance systems, antidrug social workers, vocational skills trainings, moving to another city and family responsibility might serve as counter measures targeti叩 those mentioned weaknesses and threats above. Conclusion This SWOT analysis highlights the complex nature of relapse. Comprehensive interventions strengtheni叩 coping skills such as virtual reality techniques are desperately needed to facilitate individuals1 sustained abstinence.
基金Project supported by the National Natural Science Foundation of China (Grant No 10774063)
文摘The dipole-length, dipole-velocity and dipole-acceleration absorption oscillator strengths for the 1s^22s-1s^2np (3 ≤ n ≤9) transitions of lithium-like systems from Z = 11 to 20 are calculated by using the energies and the multiconfiguration interaction wave functions obtained from a full core plus correlation method, in which relativistic and mass-polarization effects on the energy, as the first-order perturbation corrections, are included. The results of three forms are in good agreement with each other, and closely agree with the experimental data available in the literature. Based on the quantum defects obtained with quantum defect theory (QDT), the discrete oscillator strengths for the transitions from the ground state to highly excited states 1s^2np (n ≥ 10) and oscillator strength densities corresponding to the bound-free transitions are obtained for these ions.
文摘Coronary artery calcium data and reporting system(CAC-DRS)is a recently introduced standardized reporting system for calcium scoring on computed tomography.CAC-DRS provides four risk categories(0,1,2 and 3)along with treatment recommendations for each category.As with any other new reporting platform,CAC-DRS has both advantages and disadvantages.Improved communication,better clarity of details,organized management recommendations and utility in future research and education are the major strengths of CAC-DRS.It has many limitations such as questionable need for a new system,few missing components,use of a less accurate visual method and treatment suggestions based on expert opinion instead of clinical trials.In this contemporary review,we discuss the new reporting system CAC-DRS,its application,strengths and limitations and conclude with some remarks for the future.
基金Supported by the National Key Research and Development Program of China (Grant No. 2017YFA0402300)the National Natural Science Foundation of China (Grant Nos. 11774344 and 11474033)。
文摘The transition energies, E1 transitional oscillator strengths of the spin-allowed as well as the spin-forbidden and the corresponding transition rates, and complete M1, E2, M2 forbidden transition rates for 1s^(2), 1s2s, and 1s2p states of He I, are investigated using the multi-configuration Dirac–Hartree–Fock method. In the subsequent relativistic configuration interaction computations, the Breit interaction and the QED effect are considered as perturbation, separately. Our transition energies, oscillator strengths, and transition rates are in good agreement with the experimental and other theoretical results. As a result, the QED effect is not important for helium atoms, however, the effect of the Breit interaction plays a significant role in the transition energies, the oscillator strengths and transition rates.
文摘Adolescence is a crucial time period with especial vulnerability for development of mental health problems.Growing interest is focusing on the determinants of positive mental health in order to find the key concepts that could be influenced in the promotion of mental well-being of adolescents.In this study we aim to explore the relations between self-esteem,character strengths and experience of social inclusion as determinants of adolescents’positive mental health controlled for selected sociodemographic background factors.The study population(n=195)consisted of comprehensive school students who filled in an electronic questionnaire of adolescent’s mental well-being in Fall 2019.The questionnaire included measures of Warwick-Edinburgh Mental Well-being Scale(WEMWBS),VIA Youth-measure 96,Rosenberg Self-Esteem Scale and Experience of Social Inclusion Scale.The methods included group comparisons and General Linear Model computed by SPSS 24.0.The strongest association was found between positive mental health and self-esteem(β=0.789,p<0.001),followed by character strengths of hope and kindness and experience of social inclusion.Interestingly,family’s socioeconomic factors did not associate significantly with positive mental health in the final statistical model.In terms of our results,it seems that self-esteem,character strengths and experience of social inclusion might have stronger association with adolescents’mental well-being than family’s socioeconomic determinants.Therefore,it should be discussed whether psychological determinants overcome the individual effect of poor socioeconomic status as factors that influence positive mental health.Further studies are needed to establish these results more firmly.
文摘The Strengths and Difficulties Questionnaire (SDQ) is a brief screening measure of emotional and behavioural difficulties in children and adolescents. The aim of this study was to assess reliability and validity of the Greek version of the SDQ. A representative Greek sample of 1194 adolescents (aged 11 to 17 years) and their parents completed the SDQ along with other measures. Internal consistency reliability was determined by calculation of the Cronbach α coefficient. Varimax Orthogonal Transformation was conducted to test the factor structure of the questionnaire. Validity was further examined by investigating the correlation of the SDQ with the KIDSCREEN questionnaire and its association with demographic factors. The inter-rater agreement between parent and self-reports was analyzed with Pearson’s correlation coefficient. Intra-class correlation coefficients (ICCs) were computed to determine test-retest stability. For both parent and the self-report SDQ versions, most items loaded onto their predicted factors in consistency with the originally proposed five-factor structure. Internal consistency reliability was acceptable with a Cronbach α above 0.70 for all SDQ scales except for conduct and peer problems. Inter-rater correlations ranged from 0.33 to 0.45. Test-retest stability was good (ICCs > 0.60). Correlation coefficients between the SDQ and KIDSCREEN questionnaire were significant. Small effect sizes (d > 0.5) of the socioeconomic status were found for all of the SDQ scale mean scores. In conclusion, the SDQ was found to have satisfying psychometric properties and could be suitable for assessing emotional and behavioural problems in Greek adolescents.
基金Project supported by the Science Challenge Project(Grant No.TZ2016005)the National Key Research and Development Program of China(Grant Nos.2017YFA0403200 and 2017YFA0402300)the CAEP Foundation(Grant No.CX2019022)。
文摘The scattering matrices of e+N^(+)with J^(π)=1.5^(+)in discrete energy regions are calculated using the eigenchannel R-matrix method.We obtain good parameters of multichannel quantum defect theory(MQDT)that vary smoothly as the function of the energy resulting from the analytical continuation property of the scattering matrices.By employing the MQDT,all discrete energy levels for N could be calculated accurately without missing anyone.The MQDT parameters(i.e.,scattering matrices)can be calibrated with the available precise spectroscopy values.In this work,the optical oscillator strengths for the transition between the ground state and Rydberg series are obtained,which provide rich data for the diagnostic analysis of plasma.
文摘After the analysis of the value of rural tourism development in Suining City,the paper has pointed out that rural tourism development is an important content of Suining City accelerating economic development,a significant approach to promote social harmony and an innovation road to optimize industrial transformation.It has summarized the resources' districts and condition to develop rural tourism in Suining City.Based on "one center and four districts",the layout mode for Suining rural tourism development has been analyzed.It emphasizes that Suining rural tourism development should enhance publicity,integrate financing channels,pay attention to optimization of service quality,highlight environmental protection and insist on scientific development.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11104170 and 51071032
文摘By performing density functional theory plus U calculations, we systematically study the structural, electronic, and magnetic properties of U02 under uniaxial tensile strain. The results show that the ideal tensile strengths along the [100], [110], and [111] directions are 93.6, 2Z7, and 16.4 GPa at strains of 0.44, 0.24, and 0.16, respectively. After electronic-structure investigation for tensile stain along the [001] direction, we find that the strong mixed ionic/covalent character of U-O bond is weakened by the tensile strain and there will occur an insulator to metal transition at strain over 0.30.
文摘After fierce competition, Obama won the presidential race and was successfully elected as the firstAfrican-American President in US history. Unlike his predecessors, his success is primarily dependent on personalstruggle rather than renowned family background or remarkable personal political experience andaccomplishments; the change in US political environment reflected by the case is defined as "The ObamaPhenomenon". The Obama Phenomenon is the product of a variety of factors: The values of Individualism alongwith the philosophy of Pragmatism have built the macro-environment for it; Obama's elite political backgroundand his excellent personal strengths have laid the foundation for his success; the mistakes in domestic and foreignaffairs made by the Bush Administration made the Republican Party lose popular support, which removed theobstacles to Obama's success. This paper is to explore the reasons for Obama's success so as to contribute to abetter understanding of the changes in US society, in particular its political environment, excavate the impetus forthe changes, and rationally predict its
文摘In this work numerical codes carried out in a multiconfiguration Har-tree-Fock relativistic (HFR) approach for the P IV ion are used to obtain the oscillator strengths of each transition as well as the lifetimes of each energy level. With the existing data from several authors that contributed to the spectrum using different light sources, and optimizing the electrostatic parameters by a least-squares procedure when replacing the theoretical values by the experimental ones in the energy matrices, one obtains closer values and according to the observations for the intensities, and also of the lifetimes closer to those that would be obtained experimentally.
文摘Aim: This study determined whether prior brushing with desensitizing toothpastes (Sensodyne Rapid Relief and Colgate Pro-Relief) affected the shear bond strengths of composite to dentine surfaces after appropriate use of two different dentine bonding agents (SingleBond and PQ-1). Materials and Methods: Sixty caries free molar teeth were cleaned, disinfected and embedded in individual cylinders of polymethylmethracyrlate. The occulsal surfaces were flattened to expose dentine and finished down with 600 grit silicone carbide paper. The teeth were randomly divided into six groups of 10 teeth each. Two groups served as control where dentine surfaces were brushed with pumice slurry. Of the remaining 4 groups, 2 groups were brushed with Sensodyne Rapid Relief and 2 groups brushed with Colgate Pro-Relief. The dentine surfaces were brushed to simulate 2 weeks of twice-daily toothpaste use. The specimens in each of the control groups and experimental groups were subjected to dentine bonding procedures (Single Bond or PQ-1), and application of hybrid composite resin (Z-250) according to the manufacturer’s instructions. A universal material testing machine, with a cross head speed of 0.05 mm/min was used to determine shear bond strengths. Results: Mean shear bond strengths ranged from 5.71 MPa (Colgate pretreatment, composite bonded with Single Bond) to 9.07 MPa (Sensodyne pretreatment, composite bonded with Single Bond). Results showed neither of the main effects, of toothpaste type or bonding agent were significant (p > 0.05) but their interaction was (F = 4.25, p = 0.02). Post hoc analysis showed that teeth brushed with the Sensodyne group, treated with the unfilled dentine bonding agent had a significantly higher bond strength than those treated with the filled dentine bonding agent. Conclusion: The desensitizing toothpastes that use the mechanism of occlusion of open dentinal tubules in the preliminary management of tooth sensitivity should not have an adverse effect on future restorative treatment modalities.
文摘Energy levels, oscillator strengths, and transition probabilities, for the 1s2 2s2 2p6, 2p53l (l = 0, 1, 2), 2p54l (l = 0, 1, 2, 3) states in Ni XIX and Cu XX are calculated using COWAN code. The Correlation and relativistic effects are considered. The calculations are compared with other results in the literature. A good agreement is found. We also report on some unpublished energy values.
文摘The belt and road initiative strategy is proposed based on the stable and sustainable cooperation on economy and development between China and neighboring countries.The development of economy can affect every aspect of vocational education development.Therefore,vocational education in China must be moved toward internationalization to achieve sustainable development in the face of the implementation of the belt and road initiative strategy.The analysis data obtained through the strengths,weaknesses,opportunities,and threats analysis method on the internationalization of China’s vocational education under the background of the belt and road initiative strategy were the advantages analysis(strengths)of continuous maturity in developing of vocational education,which drives by economic development and the foreign employment and entrepreneurship guidance mechanism;the disadvantages analysis(weaknesses)of lack talent cultivation and weak branding of vocational education;analysis of support opportunities given by national policy;and threats analysis of social culture in the involved countries along the route.To further develop and expand China’s vocational education under the background of the belt and road initiative strategy,some countermeasures were proposed such as improves cultivation or training of talents,to build strong branding of China vocational education,and faces cultural challenges to facilitate the international development of China vocational education.