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PATHOLOGICAL CHARACTERISTICS OF GONADS IN NINE PATIENTS WITH TRUE HERMAPHRODITISM
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作者 郭丽娜 刘彤华 田秦杰 《Chinese Medical Sciences Journal》 CAS CSCD 1998年第2期103-106,共4页
The gonadal histopathology, and its correlation with the clinical features has been investigated in 9 true hermaphroditism patients, aged 5-21 yr. Seven of 9 patients had been raised as females, of which the chromosom... The gonadal histopathology, and its correlation with the clinical features has been investigated in 9 true hermaphroditism patients, aged 5-21 yr. Seven of 9 patients had been raised as females, of which the chromosomal karyotype was 46XX in 5 cases, 46XX/46XY and 46XX/47XXY in 2 cases. Two of 9 pa- tients were raised as males, the chromosomal karyotypes being 46XX and 46XX/46XY. All 9 patients had testicular tissue excised, and biopsies of the conserved ovarian tissue were performed. Ovotestis was the most common form of the abnormal gonads; two of 9 patients had bilateral ovotestes, seven had unilateral ovotestes (5 in right side, 2 in left side). In seven patients with a unilateral ovotestis, 6 had a contralateral ovary and one had a contralateral testis. Microscopically, the ovarian tissue of 11 ovotestes, including 6 biopsies from contealateral ovaris, were normal, with many primordal follicles and a few growing follicles. In two of the patients, aged over 15 years, evidence of ovulation was observed. In comparison, the testicu- lar tissue of the ovotestis and the one left inguinal testis was histologically abnormal, with immature semi- niferous tubules, most of which filled with Sertoli cells only. Three of 9 patients married after surgical treatment. Two of these subsequently conceived and delivered of normal infants by cesarean section. 展开更多
关键词 true hermaphroditism GONAD HISTOPATHOLOGY
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Intermittent disturbance mechanical behavior and fractional deterioration mechanical model of rock under complex true triaxial stress paths 被引量:3
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作者 Zhi Zheng Hongyu Xu +3 位作者 Kai Zhang Guangliang Feng Qiang Zhang Yufei Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第1期117-136,共20页
Mechanical excavation,blasting,adjacent rockburst and fracture slip that occur during mining excavation impose dynamic loads on the rock mass,leading to further fracture of damaged surrounding rock in three-dimensiona... Mechanical excavation,blasting,adjacent rockburst and fracture slip that occur during mining excavation impose dynamic loads on the rock mass,leading to further fracture of damaged surrounding rock in three-dimensional high-stress and even causing disasters.Therefore,a novel complex true triaxial static-dynamic combined loading method reflecting underground excavation damage and then frequent intermittent disturbance failure is proposed.True triaxial static compression and intermittent disturbance tests are carried out on monzogabbro.The effects of intermediate principal stress and amplitude on the strength characteristics,deformation characteristics,failure characteristics,and precursors of monzogabbro are analyzed,intermediate principal stress and amplitude increase monzogabbro strength and tensile fracture mechanism.Rapid increases in microseismic parameters during rock loading can be precursors for intermittent rock disturbance.Based on the experimental result,the new damage fractional elements and method with considering crack initiation stress and crack unstable stress as initiation and acceleration condition of intermittent disturbance irreversible deformation are proposed.A novel three-dimensional disturbance fractional deterioration model considering the intermediate principal stress effect and intermittent disturbance damage effect is established,and the model predicted results align well with the experimental results.The sensitivity of stress states and model parameters is further explored,and the intermittent disturbance behaviors at different f are predicted.This study provides valuable theoretical bases for the stability analysis of deep mining engineering under dynamic loads. 展开更多
关键词 true triaxial static and disturbance test Mechanical properties Failure mechanism and precursor Intermittent disturbance effect Fractional mechanical model
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Microdynamic mechanical properties and fracture evolution mechanism of monzogabbro with a true triaxial multilevel disturbance method
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作者 Zhi Zheng Bin Deng +3 位作者 Hong Liu Wei Wang Shuling Huang Shaojun Li 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期385-411,共27页
The far-field microdynamic disturbance caused by the excavation of deep mineral resources and underground engineering can induce surrounding rock damage in high-stress conditions and even lead to disasters.However,the... The far-field microdynamic disturbance caused by the excavation of deep mineral resources and underground engineering can induce surrounding rock damage in high-stress conditions and even lead to disasters.However,the mechanical properties and damage/fracture evolution mechanisms of deep rock induced by microdynamic disturbance under three-dimensional stress states are unclear.Therefore,a true triaxial multilevel disturbance test method is proposed,which can completely simulate natural geostress,excavation stress redistribution(such as stress unloading,concentration and rotation),and subsequently the microdynamic disturbance triggering damaged rock failure.Based on a dynamic true triaxial test platform,true triaxial microdynamic disturbance tests under different frequency and amplitudes were carried out on monzogabbro.The results show that increasing amplitude or decreasing frequency diminishes the failure strength of monzogabbro.Deformation modulus gradually decreases during disturbance failure.As frequency and amplitude increase,the degradation rate of deformation modulus decreases slightly,disturbance dissipated energy increases significantly,and disturbance deformation anisotropy strengthens obviously.A damage model has been proposed to quantitatively characterize the disturbance-induced damage evolution at different frequency and amplitude under true triaxial stress.Before disturbance failure,the micro-tensile crack mechanism is dominant,and the micro-shear crack mechanism increases significantly at failure.With the increase of amplitude and frequency,the micro-shear crack mechanism increases.When approaching disturbance failure,the acoustic emission fractal dimension changes from a stable value to local large oscillation,and finally increases sharply to a high value at failure.Finally,the disturbance-induced failure mechanism of surrounding rock in deep engineering is clearly elucidated. 展开更多
关键词 true triaxial disturbance test Mechanical properties Fracture evolution mechanism Disturbance-induced damage evolution Failure mechanism and precursor
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BGP in Nigeria--25 Years of Staying True to Our Original Aspirations Through Thick and Thin
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作者 Yang Tao 《China Oil & Gas》 CAS 2024年第1期52-56,共5页
Aspan of twenty-five years,for a company,constitutes a engthy and eventful journey.Twenty-five years ago,a group of oil professionals from the Bureau of Geophysical Prospecting INC (hereinafter referred to as BGP),set... Aspan of twenty-five years,for a company,constitutes a engthy and eventful journey.Twenty-five years ago,a group of oil professionals from the Bureau of Geophysical Prospecting INC (hereinafter referred to as BGP),set foot on the land of Nigeria and embarked on a legendary journey.This is a narrative of resilience,commitment,and heartfelt passion,an inspiring saga that touches the soul. 展开更多
关键词 CONSTITUTE true GEOPHYSICAL
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All Voices Should Be Heard and Heeded in a True Democracy
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作者 ZHANG HUI 《China Today》 2024年第5期46-49,共4页
For all its different forms,democracy is expected to promote people’s well-being,instead of being weaponized to justify hegemony,as democracy is also a principle of global governance.
关键词 true VOICE SHOULD
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Experimental and numerical study on dynamic mechanical behaviors of shale under true triaxial compression at high strain rate
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作者 Xiaoping Zhou Linyuan Han +1 位作者 Jing Bi Yundong Shou 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期149-165,共17页
High-energy gas fracturing of shale is a novel,high efficacy and eco-friendly mining technique,which is a typical dynamic perturbing behavior.To effectively extract shale gas,it is important to understand the dynamic ... High-energy gas fracturing of shale is a novel,high efficacy and eco-friendly mining technique,which is a typical dynamic perturbing behavior.To effectively extract shale gas,it is important to understand the dynamic mechanical properties of shale.Dynamic experiments on shale subjected to true triaxial compression at different strain rates are first conducted in this research.The dynamic stress-strain curves,peak strain,peak stress and failure modes of shale are investigated.The results of the study indicate that the intermediate principal stress and the minor principal stress have the significant influence on the dynamic mechanical behaviors,although this effect decreases as the strain rate increases.The characteristics of compression-shear failure primarily occur in shale subjected to triaxial compression at high strain rates,which distinguishes it from the fragmentation characteristics observed in shale under dynamic uniaxial compression.Additionally,a numerical three-dimensional Split Hopkinson Pressure Bar(3D-SHPB),which is established by coupling PFC3D and FLAC3D methods,is validated to replicate the laboratory characteristics of shale.The dynamic mechanical characteristics of shale subjected to different confining stresses are systematically investigated by the coupling PFC3D and FLAC3D method.The numerical results are in good agreement with the experimental data. 展开更多
关键词 Dynamic behaviors true triaxial compression High strain rates Dynamic failure mechanism PFC3D-FLAC3D coupled method
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Anisotropic strength,deformation and failure of gneiss granite under high stress and temperature coupled true triaxial compression
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作者 Hongyuan Zhou Zaobao Liu +2 位作者 Fengjiao Liu Jianfu Shao Guoliang Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期860-876,共17页
The anisotropic mechanical behavior of rocks under high-stress and high-temperature coupled conditions is crucial for analyzing the stability of surrounding rocks in deep underground engineering.This paper is devoted ... The anisotropic mechanical behavior of rocks under high-stress and high-temperature coupled conditions is crucial for analyzing the stability of surrounding rocks in deep underground engineering.This paper is devoted to studying the anisotropic strength,deformation and failure behavior of gneiss granite from the deep boreholes of a railway tunnel that suffers from high tectonic stress and ground temperature in the eastern tectonic knot in the Tibet Plateau.High-temperature true triaxial compression tests are performed on the samples using a self-developed testing device with five different loading directions and three temperature values that are representative of the geological conditions of the deep underground tunnels in the region.Effect of temperature and loading direction on the strength,elastic modulus,Poisson’s ratio,and failure mode are analyzed.The method for quantitative identification of anisotropic failure is also proposed.The anisotropic mechanical behaviors of the gneiss granite are very sensitive to the changes in loading direction and temperature under true triaxial compression,and the high temperature seems to weaken the inherent anisotropy and stress-induced deformation anisotropy.The strength and deformation show obvious thermal degradation at 200℃due to the weakening of friction between failure surfaces and the transition of the failure pattern in rock grains.In the range of 25℃ 200℃,the failure is mainly governed by the loading direction due to the inherent anisotropy.This study is helpful to the in-depth understanding of the thermal-mechanical behavior of anisotropic rocks in deep underground projects. 展开更多
关键词 Anisotropic strength and deformation true triaxial compression Thermal mechanical coupling Deep rock mechanics High temperature rock mechanics
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THE ETERNITY OF TRUE FRIENDSHIP EXCLUSIVE INTERVIEW WITH CHINESE AMBASSADOR TO MALAYSIA OUYANG YUJING
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作者 Guo Xixian 《China Report ASEAN》 2024年第6期16-19,共4页
China and Malaysia established diplomatic ties fifty years ago.Over the past half-century,the bilateral relationship has made great progress in various fields,delivering tangible benefits to the people of the two coun... China and Malaysia established diplomatic ties fifty years ago.Over the past half-century,the bilateral relationship has made great progress in various fields,delivering tangible benefits to the people of the two countries and making positive contributions to the peace,stability,and prosperity of the region. 展开更多
关键词 true peace AMBA
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A Corpus-Based Study on the Translators’Styles in the English Versions of The True Story of Ah-Q
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作者 SUN Huan-ni 《Journal of Literature and Art Studies》 2023年第9期643-649,共7页
The True Story of Ah-Q written by Lu Xun has been translated into forty different languages,making great contributions to the external dissemination of Chinese culture.This paper adopts the corpus stylistics method to... The True Story of Ah-Q written by Lu Xun has been translated into forty different languages,making great contributions to the external dissemination of Chinese culture.This paper adopts the corpus stylistics method to analyze the translators’styles presented by William A.Lyell and Julia Lovell’s translations of Ah-Q.Based on the self-built comparable corpus of the two translations,the paper investigates and analyzes them from the lexical and sentence level.In terms of vocabulary,the translations are statistically analyzed from the standardized type-token ratio,word frequency,word length and vocabulary density;at the sentence level,the article studies the average sentence lengths and sentence complexity.The first major finding is that Lovell’s vocabulary is richer than that of Lyell,and Lovell’s average word length is longer.Also,the average sentence length of both translations exceeds the original text,and Lovell has the highest average sentence length.Secondly,Lovell prefers to use simple sentences while Lyell prefers complex sentences.Nevertheless,both of them strive to make Lu Xun’s works understandable to foreign readers,thus understanding Chinese culture better. 展开更多
关键词 The true Story of Ah-Q corpus stylistics method translators’styles
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Experimental study of the dynamic mechanical responses and failure characteristics of coal under true triaxial confinements 被引量:4
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作者 Zhanguo Ma Pengfei Yan +3 位作者 Shixing Cheng Peng Gong Fuzhou Qi Jianguo Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第6期761-772,共12页
Investigations on the dynamic mechanical properties and failure mechanisms of coal under in-situ stress is essential for the prevention of dynamic disasters in deep coal mines.Thus,a modified true triaxial Hopkinson b... Investigations on the dynamic mechanical properties and failure mechanisms of coal under in-situ stress is essential for the prevention of dynamic disasters in deep coal mines.Thus,a modified true triaxial Hopkinson bar was employed to explore the dynamic mechanical behaviors of coal at different confining pressures(0–20 MPa)and strain rates(40–220 s^(-1)).The results show that the dynamic peak stress is positively correlated with lateral static pre-stressσy andσz,but negatively correlated with axial static prestressσx.At approximate strain rates,increasing the lateral static pre-stress facilitates increasing the dynamic peak stress,but the minimum lateral static pre-stress is the primary factor limiting a significant increase in dynamic peak stress of coal.Furthermore,the dynamic differential stress is linearly related to the logarithm of strain rate,and the peak strain varies linearly with strain rate.However,there is no significant correlation between confining pressure and peak strain.Moreover,X-ray CT images and photographic fracture observations of coal samples show the failure patterns under uniaxial and triaxial conditions are splitting failure and shear failure,respectively.The device provides a viable approach for fully comprehending the dynamic mechanical behaviors of rock-like material in complex stress conditions. 展开更多
关键词 COAL true triaxial SHPB test Dynamic mechanical properties Failure characteristics
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A testing system to understand rock fracturing processes induced by different dynamic disturbances under true triaxial compression 被引量:4
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作者 Xia-Ting Feng Mian Tian +1 位作者 Chengxiang Yang Benguo He 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第1期102-118,共17页
In this context,a testing system to understand rock fracturing processes induced by different dynamic disturbances under true triaxial compression was developed.The system is mainly composed of a static loading subsys... In this context,a testing system to understand rock fracturing processes induced by different dynamic disturbances under true triaxial compression was developed.The system is mainly composed of a static loading subsystem,a dynamic loading subsystem,a specimen box subsystem,and a data measurement subsystem.The static loading subsystem uses low stiffness loss frame structure technology,which greatly improves the frame stiffness in the three principal stress directions(up to 20 GN/m)and ensures the demand of the disturbance experiment in both the prepeak and postpeak stages.The disturbance loads with frequency of 0e20 Hz and stress level of 0e30 MPa were applied using large flow parallel oil source technology characterized with high heat dissipation efficiency.For the disturbance loads with frequency of 100e500 Hz and stress level of 0e30 MPa,they were realized by using high-frequency and centimeter-per-second-scale low-speed disturbance rod technology.Three rigid self-stabilizing specimen boxes were utilized to provide support for the specimen and deformation sensors,ensuring the stability and accuracy of the data obtained.To verify the performance of the true triaxial test system,disturbance experiments were conducted on granite specimens.The results show that the experimental device satisfies the requirements of original design,with an excellent repeatability and reliable testing results. 展开更多
关键词 Low-frequency and low-amplitude full surface disturbance true triaxial system Prepeak and postpeak dynamic disturbance Rockburst-induced stress wave Blasting-induced stress wave Hard rock
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Mutual impact of true triaxial stress, borehole orientation and bedding inclination on laboratory hydraulic fracturing of Lushan shale 被引量:3
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作者 Yongfa Zhang Anfa Long +2 位作者 Yu Zhao Arno Zang Chaolin Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第12期3131-3147,共17页
Unconventional resources like shale gas has been the focus of intense research and development for two decades. Apart from intrinsic geologic factors that control the gas shale productivity (e.g. organic matter conten... Unconventional resources like shale gas has been the focus of intense research and development for two decades. Apart from intrinsic geologic factors that control the gas shale productivity (e.g. organic matter content, bedding planes, natural fractures, porosity and stress regime among others), external factors like wellbore orientation and stimulation design play a role. In this study, we present a series of true triaxial hydraulic fracturing experiments conducted on Lushan shale to investigate the interplay of internal factors (bedding, natural fractures and in situ stress) and external factors (wellbore orientation) on the growth process of fracture networks in cubic specimens of 200 mm in length. We observe relatively low breakdown pressure and fracture propagation pressure as the wellbore orientation and/or the maximum in situ stress is subparallel to the shale bedding plane. The wellbore orientation has a more prominent effect on the breakdown pressure, but its effect is tapered with increasing angle of bedding inclination. The shale breakdown is followed by an abrupt response in sample displacement, which reflects the stimulated fracture volume. Based on fluid tracer analysis, the morphology of hydraulic fractures (HF) is divided into four categories. Among the categories, activation of bedding planes (bedding failure, BF) and natural fractures (NF) significantly increase bifurcation and fractured areas. Under the same stress regime, a horizontal wellbore is more favorable to enhance the complexity of hydraulic fracture networks. This is attributed to the relatively large surface area in contact with the bedding plane for the horizontal borehole compared to the case with a vertical wellbore. These findings provide important references for hydraulic fracturing design in shale reservoirs. 展开更多
关键词 true triaxial hydraulic fracturing experiment In situ stress state Bedding planes Natural fractures Wellbore orientation Shale reservoirs
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Effects of intermediate stress on deep rock strainbursts under true triaxial stresses 被引量:1
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作者 Lihua Hu Liyuan Yu +2 位作者 Minghe Ju Xiaozhao Li Chun’an Tang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第3期659-682,共24页
The effect of intermediate stress(in situ tunnel axial)on a strainburst is studied with a threedimensional(3D)bonded block distinct element method(DEM).A series of simulations of strainbursts under true triaxial in si... The effect of intermediate stress(in situ tunnel axial)on a strainburst is studied with a threedimensional(3D)bonded block distinct element method(DEM).A series of simulations of strainbursts under true triaxial in situ stress conditions(i.e.high tangential stress,moderate intermediate stress and low radial stress)of near-boundary rock masses are performed.Compared with the experimental results,the DEM model is able to capture the stress-strain response,failure pattern and energy balance of strainbursts.The fracturing processes of strainbursts are also numerically reproduced.Numerical results show that,as the intermediate stress increases:(1)The peak strain of strainbursts increases,the yield stress increases,the rock strength increases linearly,and the ratio of yield stress to rock strength decreases,indicating that the precursory information on strainbursts is enhanced;(2)Tensile and shear cracks increase significantly,and slabbing and bending of rock plates are more pronounced;and(3)The stored elastic strain energy and dissipated energy increase linearly,whereas the kinetic energy of the ejected rock fragments increases approximately exponentially,implying an increase in strainburst intensity.By comparing the experimental and numerical results,the effect of intermediate stress on the rock strength of strainbursts is discussed in order to address three key issues.Then,the Mogi criterion is applied to construct new strength criteria for strainbursts by converting the one-face free true triaxial stress state of a strainburst to its equivalent true triaxial stress state.In summary,the effect of intermediate stress on strainbursts is a double-edged sword that can enhance the rock strength and the precursory information of a strainburst,but also increase its intensity. 展开更多
关键词 Strainbursts Intermediate stress Distinct element method(DEM) Structural failure true triaxial Strength criterion
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A true triaxial strength criterion for rocks by gene expression programming 被引量:1
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作者 Jian Zhou Rui Zhang +1 位作者 Yingui Qiu Manoj Khandelwal 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第10期2508-2520,共13页
Rock strength is a crucial factor to consider when designing and constructing underground projects.This study utilizes a gene expression programming(GEP)algorithm-based model to predict the true triaxial strength of r... Rock strength is a crucial factor to consider when designing and constructing underground projects.This study utilizes a gene expression programming(GEP)algorithm-based model to predict the true triaxial strength of rocks,taking into account the influence of rock genesis on their mechanical behavior during the model building process.A true triaxial strength criterion based on the GEP model for igneous,metamorphic and magmatic rocks was obtained by training the model using collected data.Compared to the modified Weibols-Cook criterion,the modified Mohr-Coulomb criterion,and the modified Lade criterion,the strength criterion based on the GEP model exhibits superior prediction accuracy performance.The strength criterion based on the GEP model has better performance in R2,RMSE and MAPE for the data set used in this study.Furthermore,the strength criterion based on the GEP model shows greater stability in predicting the true triaxial strength of rocks across different types.Compared to the existing strength criterion based on the genetic programming(GP)model,the proposed criterion based on GEP model achieves more accurate predictions of the variation of true triaxial strength(s1)with intermediate principal stress(s2).Finally,based on the Sobol sensitivity analysis technique,the effects of the parameters of the three obtained strength criteria on the true triaxial strength of the rock are analysed.In general,the proposed strength criterion exhibits superior performance in terms of both accuracy and stability of prediction results. 展开更多
关键词 Gene expression programming(GEP) true triaxial strength Rock failure criteria Intermediate principal stress
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Remaining True to Our Original Aspiration,Keeping Our Mission Firmly in Mind,Let's Set Sail and Write a New Chapter:Congratulations on the new column of "Carbon Neutrality,New Energy and Emerging Field"
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作者 Editorial Office of Petroleum Exploration and Development 《Petroleum Exploration and Development》 2023年第1期F0002-F0002,共1页
Years go by and seasons flow.At this moment of waving goodbye to the unforgettable year of 2022 and welcoming the Spring Festival of the Year 2023,the Year of the Rabbit,we would like to send our sincere thanks and be... Years go by and seasons flow.At this moment of waving goodbye to the unforgettable year of 2022 and welcoming the Spring Festival of the Year 2023,the Year of the Rabbit,we would like to send our sincere thanks and best wishes for the new year to experts,authors,readers of our Journal and friends from all fields! 展开更多
关键词 since true forget
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Pursuing a Shared Future——Dreams Come True when Wind Blows
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《International Understanding》 2023年第3期52-52,共1页
The Senj Wind Power Project is invested,constructed and run by NORINCO International Cooperation Ltd.(hereinafter referred to as NORINCO International).The project kicked off in November 2018 and was officially connec... The Senj Wind Power Project is invested,constructed and run by NORINCO International Cooperation Ltd.(hereinafter referred to as NORINCO International).The project kicked off in November 2018 and was officially connected to the grid for power generation in December 2021.It produces about 530 million KWH of green electricity each year,meeting the electricity demand of at least 100,000 households while reducing carbon dioxide emissions by about 460,000 tons per year. 展开更多
关键词 invested WIND true
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A rigid true triaxial apparatus for analyses of deformation and failure features of deep weak rock under excavation stress paths
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作者 Xia-Ting Feng Xiaojun Yu +2 位作者 Yangyi Zhou Chengxiang Yang Feiyan Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第5期1065-1075,共11页
The squeezing scenario in deep weak rock tunnels can hinder underground construction.However,due to the limitations of test technologies at hand,the real excavation stress path cannot be mimicked in the laboratory.Thu... The squeezing scenario in deep weak rock tunnels can hinder underground construction.However,due to the limitations of test technologies at hand,the real excavation stress path cannot be mimicked in the laboratory.Thus,the large deformation mechanism of deep weak rocks still remains unclear.For this,a true triaxial apparatus(TTA)to investigate the mechanical responses of deep weak rock under excavation stress paths in field and reveal the squeezing mechanism of deep tunnels is assembled and developed at Northeastern University,China.The apparatus can perform instantaneous unloading in s3 direction based on electromagnetism technology.In addition,uniform loading and deformation measurements can be carried out based on the proposed linked interlocking clamp and antifriction device,even if the sample has a strong dilatation deformation performance.Next,a bore trepanning is designed to capture noiseless acoustic emission(AE)signals for deep weak rock at a low threshold.Finally,two tests were are conducted using this instrument to preliminarily understand the failure and deformation features of deep weak rock based on fractured marble.The results show that the complete stressestrain curves of fractured marble have the characteristics of low strengths and large deformations,and the larger deformation and the more serious failure occur when the fractured marble enters the post-peak state after excavation.The results show that the developed apparatus is likely to be applicable for deep weak rock engineering. 展开更多
关键词 true triaxial apparatus(TTA) Deep weak rock Large deformation Excavation stress path Instantaneous unloading
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In Pursuit of True Multilateralism:The US-hosted“Summit for Democracy”is provoking confrontation
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作者 KIRTAN BHANA 《ChinAfrica》 2023年第5期34-35,共2页
Serious concerns are being raised about the state of the US politics,economy and international relations,not only outside the country,but also inside it.The so-called“Summit for Democracy”hosted by the US in late Ma... Serious concerns are being raised about the state of the US politics,economy and international relations,not only outside the country,but also inside it.The so-called“Summit for Democracy”hosted by the US in late March focussed attention on governance and governments. 展开更多
关键词 true OUTSIDE SUMMIT
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A Dream Come True
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《ChinAfrica》 2023年第1期2-2,共1页
A historical change of shift taking place on 2 December 2022 in the space caught the world’s attention.Three Chinese taikonauts Fei Junlong,Deng Qingming and Zhang Lu on the Shenzhou 15 mission took over the work in ... A historical change of shift taking place on 2 December 2022 in the space caught the world’s attention.Three Chinese taikonauts Fei Junlong,Deng Qingming and Zhang Lu on the Shenzhou 15 mission took over the work in Chinese space station Tiangong from Shenzhou 14 crew Chen Dong,Liu Yang and Cai Xuzhe,and the latter returned to Earth on 4 December after their 183-day mission in the space.The Shenzhou 15 mission marks the last step in the building of Tiangong,as well as the operationalisation of the space station’s applications. 展开更多
关键词 true EARTH latter
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Capturing True Images
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作者 LI XIAOYU 《ChinAfrica》 2023年第8期58-59,共2页
Alexandra Pozhidaeva firmly follows the principle of“seeing is believing.”The 23-year-old Russian journalist,who recently graduated from the School of Journalism and Communication at Peking University,borrowed this ... Alexandra Pozhidaeva firmly follows the principle of“seeing is believing.”The 23-year-old Russian journalist,who recently graduated from the School of Journalism and Communication at Peking University,borrowed this fundamental principle from Chinese President Xi Jinping.In 2021,while still pursuing her master’s degree,she joined 44 other international students to write a congratulatory letter to Xi on the occasion of the centenary of the Communist Party of China(CPC). 展开更多
关键词 true JOURNAL LETTER
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