While the moisture content of soil affects significantly the blast impulse of shallow buried explosives,the role of surface-covering water(SCW)on soil in such blast impulse remains elusive.A combined experimental and ...While the moisture content of soil affects significantly the blast impulse of shallow buried explosives,the role of surface-covering water(SCW)on soil in such blast impulse remains elusive.A combined experimental and numerical study has been carried out to characterize the effect of SCW on transferred impulse and loading magnitude of shallow buried explosives.Firstly,blast tests of shallow buried explosives were conducted,with and without the SCW,to quantitatively assess the blast loading impulse.Subsequently,finite element(FE)simulations were performed and validated against experimental measurement,with good agreement achieved.The validated FE model was then employed to predict the dynamic response of a fully-clamped metallic circular target,subjected to the explosive impact of shallow buried explosives with SCW,and explore the corresponding physical mechanisms.It was demonstrated that shallow buried explosives in saturated soil generate a greater impulse transferred towards the target relative to those in dry soil.The deformation displacement of the target plate is doubled.Increasing the height of SCW results in enhanced center peak deflection of the loaded target,accompanied by subsequent fall,due to the variation of deformation pattern of the loaded target from concentrated load to uniform load.Meanwhile,the presence of SCW increases the blast impulse transferred towards the target by three times.In addition,there exists a threshold value of the burial depth that maximizes the impact impulse.This threshold exhibits a strong sensitivity to SCW height,decreasing with increasing SCW height.An empirical formula for predicting threshold has been provided.Similar conclusions can be drawn for different explosive masses.The results provide technical guidance on blast loading intensity and its spatial distribution considering shallow buried explosives in coast-land battlefields,which can ultimately contribute to better protective designs.展开更多
Strong surface impact will produce strong vibration,which will pose a threat to the safety of nearby buried pipelines and other important lifeline projects.Based on the verified numerical method,a comprehensive numeri...Strong surface impact will produce strong vibration,which will pose a threat to the safety of nearby buried pipelines and other important lifeline projects.Based on the verified numerical method,a comprehensive numerical parameter analysis is conducted on the key influencing factors of the vibration isolation hole(VIH),which include hole diameter,hole net spacing,hole depth,hole number,hole arrangement,and soil parameters.The results indicate that a smaller ratio of net spacing to hole diameter,the deeper the hole,the multi-row hole,the hole adoption of staggered arrangements,and better site soil conditions can enhance the efficiency of the VIH barrier.The average maximum vibration reduction efficiency within the vibration isolation area can reach 42.2%.The vibration safety of adjacent oil pipelines during a dynamic compaction projection was evaluated according to existing standards,and the measurement of the VIH was recommended to reduce excessive vibration.The single-row vibration isolation scheme and three-row staggered arrangement with the same hole parameters are suggested according to different cases.The research findings can serve as a reference for the vibration safety analysis,assessment,and control of adjacent underground facilities under the influence of strong surface impact loads.展开更多
As one of the important components of high-effi-ciency perovskite/silicon series devices,wide-bandgap(WBG)perovskite solar cells(PSCs)have been suffering from serious carrier transport barriers and huge open-circuit v...As one of the important components of high-effi-ciency perovskite/silicon series devices,wide-bandgap(WBG)perovskite solar cells(PSCs)have been suffering from serious carrier transport barriers and huge open-circuit voltage deficit de-rived from non-radiative recombination,especial-ly at the buried interface that are often overlooked.Herein,we combined cationic and anion passiva-tion strategies via ammonium tetra-n-butyl tetrafluoroborate(TBABF_(4))pre-treating the buried interface.Theoretical calculation predicts that the tetrabutylammonium(TBA^(+))organic cations and(tetrafluoroborate)BF_(4)^(−)anions can easily interact with charged interfacial defect.Characterizations further confirm the enhance-ment of carrier transport performance and decrease in defect density upon TBABF4 pre-treat-ment.Consequently,a power conversion efficiency of 21.35%with an ultrahigh filling factor of 84.12%is obtained for 1.68 eV-WBG inverted PSCs.In addition,the device with TBABF4 pre-treatment demonstrates excellent shelf,thermal,and operational stability.展开更多
Based on drilling,mud logging,core,seismic and imaging logging data,this paper studies the identification and evolution process of negative inversion structures in the Carboniferous buried hills in the No.1 and No.2 f...Based on drilling,mud logging,core,seismic and imaging logging data,this paper studies the identification and evolution process of negative inversion structures in the Carboniferous buried hills in the No.1 and No.2 fault zones of Weixinan Sag,Beibu Gulf Basin,China,and reveals the controls of these structures on high-quality reservoirs.The No.2 fault zone develops significant negative inversion structures in the Carboniferous buried hills,as a result of multi-stage transformations of compressive-tensile stress fields in the period from the Late Hercynian to the Himalayan.The Hercynian carbonates laid the material basis for the formation of high-quality reservoirs.The negative inversion structures mainly control the development of high-quality reservoirs in buried hills through:(1)creating large-scale fractures to increase reservoir space and improve oil-gas flow pathways;(2)regulating stratigraphic differential denudation to highlight dominant lithology for later reservoir transformation;(3)shaping the paleogeomorphological highlands to provide favorable conditions for superficial karstification.The negative inversion structures form a high-quality,composite reservoir space with the synergistic existence of superficial dissolution fractures/cavities and burial-enhanced karst systems through the coupling of fracture network creation,formation denudation screening and multi-stage karst transformation.The research results have guided the breakthrough of the first exploratory well with a daily oil production over 1000 m^(3)in carbonate buried-hill reservoir in the Beibu Gulf Basin,and provide referential geological basis for finding more reserves and achieving higher production in the Carboniferous buried hills in the Weixinan Sag.展开更多
Weijia Guyot,located in the western Pacific Ocean,has become a research focus due to its abundant cobalt-rich ferromanganese(Fe-Mn)crusts.While most studies on Fe-Mn crusts on seamounts have focused on the exposed var...Weijia Guyot,located in the western Pacific Ocean,has become a research focus due to its abundant cobalt-rich ferromanganese(Fe-Mn)crusts.While most studies on Fe-Mn crusts on seamounts have focused on the exposed variety,less attention has been paid to potential buried crusts.This study presents a preliminary geochemical and chronological study of buried Fe-Mn crusts at Weijia Guyot.The findings suggest that these buried crusts began to form around 57.5 Ma and ceased growing at approximately 46.3 Ma.Following the formation of Weijia Guyot through volcanic eruption,it did not experience continuous and steady subsidence to its current depth.Instead,an exhumation process took place from deep to shallow depths between 46.3 and 11.6 Ma.This process brought the Fe-Mn crusts into shallow water environments,halting their growth.During this time,Weijia Guyot was located near the equatorial Pacific Ocean and was exposed to an extended period of phosphatization.This exposure led to a depletion of key metallogenic elements,such as Co,Ni and Cu,within the Fe-Mn crusts,while P2O5 and CaO levels increased significantly.Since the Middle Miocene,the crusts have been progressively buried by pelagic sediments.展开更多
The BZ oilfield in the Bohai Sea is a rare,highly volatile reservoir with fractures in the metamorphic rocks of buried hills.Clarifying the mechanism of gas injection for improving oil recovery and determining the opt...The BZ oilfield in the Bohai Sea is a rare,highly volatile reservoir with fractures in the metamorphic rocks of buried hills.Clarifying the mechanism of gas injection for improving oil recovery and determining the optimal way to deploy injection-production well networks are critical issues that must be urgently addressed for efficient oilfield development.Experimental research on the mixed-phase displacement mechanism through gas injection into indoor formation fluids was conducted to guide the efficient development of gas injection in oil fields.We established a model of dual-medium reservoir composition and researched the deployment strategy for a three-dimensional well network for gas injection development.The coupling relationship between key influencing factors of the well network and fracture development was also quantitatively analyzed.The results show that the solubility of the associated gas and strong volatile oil system injected into the BZ oilfield is high.This high solubility demonstrates a mixed-phase displacement mechanism involving intermediate hydrocarbons,dissolution and condensation of medium components,and coexistence of extraction processes.Injecting gas and crude oil can achieve a favorable mixing effect when the local formation pressure is greater than 35.79 MPa.Associated gas reinjection is recommended to supplement energy for developing the highly volatile oil reservoirs in the fractured buried hills of the BZ oilfield.This recommendation involves fully utilizing the structural position and gravity-assisted oil displacement mechanism to deploy an injection-production well network.Gas injection points should be constructed at the top of high areas,and oil production points should be placed at the middle and lower parts of low areas.This approach forms a spatial threedimensional well network.By adopting high inclination well development,the oil production well forms a 45°angle with the fracture direction,which increases the drainage area and enhances single-well production capacity.The optimal injection-production well spacing along the fracture direction is approximately 1000 m,while the reasonable well spacing in the vertical fracture direction is approximately 800 m.The research results were applied to the development practice of the buried hills in the BZ oilfield,which achieved favorable development results.These outcomes provide a valuable reference for the formulation of development plans and efficient gas injection development in similar oil and gas fields in buried hills.展开更多
Numerous defects at the buried interface of perovskite film and the exacerbated oxidation and degradation of tin-lead(Sn-Pb)perovskites induced by poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS),du...Numerous defects at the buried interface of perovskite film and the exacerbated oxidation and degradation of tin-lead(Sn-Pb)perovskites induced by poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS),due to its hygroscopic and acidic nature,limit performance improvement of SnPb perovskite solar cells(PSCs).To address these issues,1-Ethyl-3-Guanidinothiourea-Hydrochloride(EGH)was employed as a multifunctional modifier at the PEDOT:PSS/perovskite interface to regulate the buried interface behaviors of Sn-Pb PSCs.EGH can not only passivate the defects of the perovskite buried interface and regulate the work function of PEDOT:PSS for a more matched interface energy level,but also prevent the perovskite film from erosion damage by the acidic PEDOT:PSS for a more stable PEDOT:PSS/perovskite interface.Moreover,the interfacial charge transport dynamics were significantly improved by obviously suppressing interfacial non-radiative recombination losses.As a consequence,EGH-tailored 1.25 eV Sn-Pb PSCs yielded a champion PCE of 23.20%,featuring enhanced long-term stability.展开更多
Uneven terrain significantly increases the seismic risk of tunnels in loess deposits.To investigate the variations in optimal intensity measures(IMs)for shallowly buried loess tunnels considering biased terrain,nonlin...Uneven terrain significantly increases the seismic risk of tunnels in loess deposits.To investigate the variations in optimal intensity measures(IMs)for shallowly buried loess tunnels considering biased terrain,nonlinear dynamic analyses were conducted to obtain seismic responses validated by the actual damage pattern.Then IMs were evaluated based on the automatic calculation of the time history damage index fulfilled by a compiled Python program.Results showed that the plastic strain zone progressively developed and extended from the vault to the central slope surface with increasing seismic intensities,ultimately causing shear failure to the tunnel.For IMs at the slope top,peak ground velocity(PGV)(ζ=0.15),velocity spectrum intensity(VSI)(ζ=0.20),and peak spectrum velocity(PSv)(ζ=0.22)were all suitable for seismic fragility assessment.The VSI(ζ=0.17)was optimal,followed by PGV(ζ=0.19)and PSv(ζ=0.2)for those at the slope foot.Acceleration-related IMs were more sensitive to terrain variation.Comparative analyses demonstrated smaller damage probabilities for the IMs at the slope top than those at the slope foot under the same intensity level.The impact of unfavorable terrain on tunnels was accentuated as those located in uneven mountainous regions became more vulnerable to ground shaking.展开更多
Perovskite solar cells(PSC)are considered as a promising photovoltaic technology due to their low cost and high efficiency exceeding 26.8%.Ultra-lightweight flexible perovskite solar cells(FPSCs)can be applied to many...Perovskite solar cells(PSC)are considered as a promising photovoltaic technology due to their low cost and high efficiency exceeding 26.8%.Ultra-lightweight flexible perovskite solar cells(FPSCs)can be applied to many fields such as architecture and portable devices.Although the photovoltaic conversion efficiency(PCE)of FPSC has exceeded 24%in the past few years,further application of FPSC is constrained by the challenges posed by limitation of critical material components.Here,we discussed recent research progress of key FPSC materials,mechanical endurance,low-temperature fabrication,etc.With the advantages of high brightness,collimation and resolution,we specially introduced the application of synchrotron radiation grazing incidence wide-angle X-ray scattering(GIWAXS)to directly observe the perovskite buried interface structure and corresponding mechanical stability of FPSCs without any damage.Finally,we summarize the challenges and propose an outlook about the large-scale preparation of efficient and stable FPSC modules.展开更多
Deeply buried mountain tunnels are often exposed to the risk of rock bursts,which always cause serious damage to the supporting structures and threaten the safety of the engineers.Due to the limited data available,a s...Deeply buried mountain tunnels are often exposed to the risk of rock bursts,which always cause serious damage to the supporting structures and threaten the safety of the engineers.Due to the limited data available,a suitable approach to predict the rockburst tendency at the preliminary stage becomes very important.In this study,an integrated methodology combining 3D initial stress inversion and rockburst tendency prediction was developed and subsequently applied to a case study of the Sangzhuling Tunnel on the Sichuan–Tibet Railway.The numerical modelling involved inverting the initial stress field using a multiple linear regression method.The tunnel excavation was simulated separately by FDM and DEM,based on a stress boundary condition from the inverted stress field.The comparative analysis demonstrates that the rockburst ratio calculated using DEM(76.70%)exhibits a slight increase compared to FDM(75.38%),and the rockburst location is consistent with the actual situation.This suggests that DEM is more suitable for simulating the stress redistribution during excavation in a jointed rock mass.The numerical simulation combined with the deviatoric stress approach effectively predicts rockburst tendency,meeting the engineering requirements.Despite its limitations,numerical simulation remains a reliable method for predicting rock bursts.展开更多
Caves located in the buried hill reservoir of granite bedrock in Bongor Basin,Chad,are excessively small and cannot be identifi ed in conventional refl ection wave imaging profi les because their refl ection character...Caves located in the buried hill reservoir of granite bedrock in Bongor Basin,Chad,are excessively small and cannot be identifi ed in conventional refl ection wave imaging profi les because their refl ection characteristics are suppressed by the strong refl ection of the weathering crust at the top of the buried hill.In contrast to refl ection wave imaging,which refl ects the refl ection characteristics of continuous interfaces,scattered wave imaging refl ects the reflection characteristics of discontinuous geological bodies.Scattering waves can be produced in the presence of discontinuous points,such as karst caves,fractures,and stratum vanishing points.Scattering imaging can accurately provide the location of discontinuous abnormal bodies,highlight the seismic reflection characteristics of caves with weak reflections,and eliminate continuous strong reflections to strengthen the ability of seismic data to distinguish discontinuous geological bodies and solve the inability of seismic data from conventional poststack refl ection wave imaging to identify small caves in buried hills.Three-parameter wavelet spectral decomposition technology is used to depict the boundary of caves accurately in accordance with the strong energy spectral characteristics of caves in the section of the scattering imaging seismic data of the granite bedrock buried hill reservoir.Compared with the attributes extracted from conventional refl ection wave poststack seismic data,those acquired from scattering imaging bodies are more reliable and consistent with the actual location of caves on boreholes and have higher resolution.For connected wells,the attributes extracted from the conventional poststack seismic data can only predict whether caves are developed,whereas those calculated from scattering imaging can not only predict whether caves are present but also refl ects the degree of cave development.On the plane,the attributes obtained from scattering imaging calculation are more consistent with the geological law of cave development.On the basis of this fi nding and in accordance with the results of the three-parameter wavelet spectral decomposition of scattering imaging seismic data,the degree of cave development is classifi ed,and the favorable location for reservoir development in the study area is identifi ed.This solution provides an eff ective way to improve the exploration accuracy of cave-type granite buried hill reservoirs.展开更多
The chief objective of the article is to learn the spatial characteristics of stress distribution around a shallow buried cylinder Karst cave in limestone strata.Firstly,taking into account the geometry of limestone f...The chief objective of the article is to learn the spatial characteristics of stress distribution around a shallow buried cylinder Karst cave in limestone strata.Firstly,taking into account the geometry of limestone formations,and the characteristics of Karst geomorphology in China,a spatial axialsymmetrical hollow model was established.Concurrently,combining available work and the concept of elasticity,the boundary conditions are determined.Subsequently,Love displacement method was introduced,the expressions of stress components were gained.The diagram characteristics of each stress component are summarized,which are affected by various influencing factors.Finally,in order to prove the rationality of the general solution,numerical simulation was carried out on the basis of practical engineering,and the maximum error is less than 5%.Thus,the analytical solution could represent the spatial characteristics of stress distribution around a shallow buried cylinder Karst cave in limestone strata.展开更多
Various techniques have been described for reconstructing the skin of the penile shaft;however,no universally accepted standard exists for correcting buried penis in adults.We aimed to describe a new technique for cor...Various techniques have been described for reconstructing the skin of the penile shaft;however,no universally accepted standard exists for correcting buried penis in adults.We aimed to describe a new technique for correcting an adult-acquired buried penis through a diamond-shaped incision at the penopubic junction.We retrospectively analyzed data from patients treated with our technique between March 2019 and June 2023 in the Department of Andrology,Nanjing Drum Tower Hospital(Nanjing,China).Forty-two adult males with buried penises,with a mean(±standard deviation[s.d.])age of 26.6(±6.6)years,underwent surgery.All patients were obese,with an average(±s.d.)body mass index of 35.56(±3.23)kg m^(-2).In addition to phalloplasty,32 patients concurrently underwent circumcision,and 28 underwent suprapubic liposuction.The mean(±s.d.)duration of the operation was 98.02(±13.28)min.The mean(±s.d.)duration of follow-up was 6.71(±3.43)months.The length in the flaccid unstretched state postoperatively was significantly greater than that preoperatively(mean±s.d:5.55±1.19 cm vs 1.94±0.59 cm,P<0.01).Only minor complications,such as wound disruption(7.1%)and infection(4.8%),were observed.The mean(±s.d.)score of patient satisfaction was 4.02(±0.84)on a scale of 5.This technique provides excellent cosmetic and functional outcomes with a minimal risk of complications.However,additional clinical studies are needed to evaluate the long-term effects of this procedure.展开更多
On August 6,2023,a magnitude MW5.5 earthquake struck Pingyuan County,Dezhou City,Shandong Province,China.This event was significant as no large earthquakes had been recorded in the region for over a century,and no act...On August 6,2023,a magnitude MW5.5 earthquake struck Pingyuan County,Dezhou City,Shandong Province,China.This event was significant as no large earthquakes had been recorded in the region for over a century,and no active fault had been previously identified.This study collects 1309 P-wave arrival times and 866 S-wave arrival times from 74 seismic stations less than 200 km to the epicenter to constrain the spatial distribution of the mainshock and its 125 early aftershocks by the double difference earthquake relocation method,and selects 864 P-waveforms from 288 stations located within 800 km of the epicenter to constrain the focal mechanism solution of the mainshock through centroid moment tensor inversion.The relocation and the inversion indicate,the Pingyuan MW5.5 earthquake was caused by a rupture on a buried fault,likely an extensive segment of the Gaotang fault.This buried fault exhibited a dip of approximately 75°to the northwest,with a strike of 222°,similar to the Gaotang fault.The rupture initiated at the depth of 18.6 km and propagated upward and northeastward.However,the ground surface was not broken.The total duration of the rupture was~6.0 s,releasing the scalar moment of 2.5895×1017 N·m,equivalent to MW5.54.The moment rate reached the maximum only 1.4 seconds after the rupture initiation,and the 90%scalar moment was released in the first 4.6 s.In the first 1.4 seconds of the rupture process,the rupture velocity was estimated to be 2.6 km/s,slower than the local S-wave velocity.As the rupture neared its end,the rupture velocity decreased significantly.This study provides valuable insights into the seismic characteristics of the Pingyuan MW5.5 earthquake,shedding light on the previously unidentified buried fault responsible for the seismic activity in the region.Understanding the behavior of such faults is crucial for assessing seismic hazards and enhancing earthquake preparedness in the future.展开更多
The buried interface in the perovskite solar cell(PSC)has been regarded as a breakthrough to boost the power conversion efficiency and stability.However,a comprehensive manipulation of the buried interface in terms of...The buried interface in the perovskite solar cell(PSC)has been regarded as a breakthrough to boost the power conversion efficiency and stability.However,a comprehensive manipulation of the buried interface in terms of the transport layer,buried interlayer,and perovskite layer has been largely overlooked.Herein,we propose the use of a volatile heterocyclic compound called 2-thiopheneacetic acid(TPA)as a pre-buried additive in the buried interface to achieve cross-layer all-interface defect passivation through an in situ bottom-up infiltration diffusion strategy.TPA not only suppresses the serious interfacial nonradiative recombination losses by precisely healing the interfacial and underlying defects but also effectively enhances the quality of perovskite film and releases the residual strain of perovskite film.Owing to this versatility,TPA-tailored CsPbBr3 PSCs deliver a record efficiency of 11.23% with enhanced long-term stability.This breakthrough in manipulating the buried interface using TPA opens new avenues for further improving the performance and reliability of PSC.展开更多
Imaging the wave velocity field surrounding a borehole while drilling is a promising and urgently needed approach for extending the exploration range of the borehole point.This paper develops a drilling process detect...Imaging the wave velocity field surrounding a borehole while drilling is a promising and urgently needed approach for extending the exploration range of the borehole point.This paper develops a drilling process detection(DPD)system consisting of a multifunctional sensor and a pilot geophone installed at the top of the drilling rod,geophones at the tunnel face,a laser rangefinder,and an onsite computer.A weighted adjoint-state first arrival travel time tomography method is used to invert the P-wave velocity field of rock mass while borehole drilling.A field experiment in the ongoing construction of a deep buried tunnel in southwestern China demonstrated the DPD system and the tomography method.Time-frequency analysis of typical borehole drilling detection data shows that the impact drilling source is a pulse-like seismic exploration wavelet.A velocity field of the rock mass in a triangular area defined by the borehole trajectory and geophone receiving line can be obtained.Both the borehole core and optical image validate the inverted P-wave velocity field.A numerical simulation of a checkerboard benchmark model is used to test the tomography method.The rapid convergence of the misfits and consistent agreement between the inverted and observed travel times validate the P-wave velocity imaging.展开更多
Based on the data from 3D seismic surveys,drilling,sidewall coring,thin sections,and tests,this paper analyzes Meso-Cenozoic geotectonic dynamics,buried-hill reservoir characteristics,and differential enrichment patte...Based on the data from 3D seismic surveys,drilling,sidewall coring,thin sections,and tests,this paper analyzes Meso-Cenozoic geotectonic dynamics,buried-hill reservoir characteristics,and differential enrichment patterns of oil and gas in the buried hills,as well as case studies of typical reservoirs,to systematically discuss the conditions required for the formation of buried-hills and reservoirs and accumulations in the large oil and gas fields in deep to ultra-deep composite buried hills in the Bohai Sea..The key findings are as follows.First,deep to ultra-deep composite buried hills developed in the offshore Bohai Bay Basin primarily due to the double-episode destruction of the North China Craton in the Yanshanian and Himalayan.The Tanlu Fault's activity and the destruction of the North China Craton worked together to create the destruction center,which moved and converged episodically from the Bohai Bay Basin's margins towards the Bozhong Sag.This led to the formation of two development zones for composite buried hills and an orderly process of mountain-building within the offshore Bohai Bay Basin and subsequently two development zones for composite buried hills,i.e.the middle and inner rim zones within the Bozhong Depression.Second,under the coupling of favorable lithologies and multi-stage structures,the middle and inner rim zones are favorable for the formation of reservoirs in fluid dissolution-pore/fracture zones underlying the weathering crust.Third,Massive hydrocarbons were produced along the middle and inner rim zones during the Episode Ⅱ craton destruction,which caused overpressure.These hydrocarbons then moved to and accumulated in the composite buried hills.Excellent conditions for the accumulation of hydrocarbons are still present in the interior and lower portions of these buried hills.These results encourage a change in buried hill research to investigate composite buried hills in three dimensions.It should be noted that the multi-stage volcanic structures in the inner rim zone of the Sag and the deep to ultra-deep composite buried hill interiors in the middle rim zone are significant successor areas for further Bohai Sea exploration.展开更多
CsPbI_(2)Br perovskite solar cells(PSCs)have drawn tremendous attention due to their suitable bandgap,excellent photothermal stability,and great potential as an ideal candidate for top cells in tandem solar cells.Howe...CsPbI_(2)Br perovskite solar cells(PSCs)have drawn tremendous attention due to their suitable bandgap,excellent photothermal stability,and great potential as an ideal candidate for top cells in tandem solar cells.However,the abundant defects at the buried interface and perovskite layer induce severe charge recombination,resulting in the open-circuit voltage(V_(oc))output and stability much lower than anticipated.Herein,a novel buried interface management strategy is developed to regulate interfacial carrier dynamics and CsPbI_(2)Br defects by introducing ammonium tetrafluoroborate(NH_(4)BF_(4)),thereby resulting in both high CsPbI_(2)Br crystallization and minimized interfacial energy losses.Specifically,NH_(4)^(+)ions could preferentially heal hydroxyl groups on the SnO_(2)surface and balance energy level alignment between SnO_(2)and CsPbI_(2)Br,enhancing charge transport efficiency,while BF_(4)^(-)anions as a quasi-halogen regulate crystal growth of CsPbI_(2)Br,thus reducing perovskite defects.Additionally,it is proved that eliminating hydroxyl groups at the buried interface enhances the iodide migration activation energy of CsPbI_(2)Br for strengthening the phase stability.As a result,the optimized CsPbI_(2)Br PSCs realize a remarkable efficiency of 17.09%and an ultrahigh V_(oc)output of 1.43 V,which is one of the highest values for CsPbI_(2)Br PSCs.展开更多
Buried interfacial voids have always been a notorious phenomenon observed in the fabrication of lead perovskite films. The existence of interfacial voids at the buried interface will capture the carrier, suppress carr...Buried interfacial voids have always been a notorious phenomenon observed in the fabrication of lead perovskite films. The existence of interfacial voids at the buried interface will capture the carrier, suppress carrier transport efficiencies, and affect the stability of photovoltaic devices. However, the impact of these buried interfacial voids on tin perovskites, a promising avenue for advancing lead-free photovoltaics, has been largely overlooked. Here, we utilize an innovative weakly polar solvent pretreatment strategy(WPSPS) to mitigate buried interfacial voids of tin perovskites. Our investigation reveals the presence of numerous voids in tin perovskites during annealing, attributed to trapped dimethyl sulfoxide(DMSO) used in film formation. The WPSPS method facilitates accelerated DMSO evaporation, effectively reducing residual DMSO. Interestingly, the WPSPS shifts the energy level of PEDOT:PSS downward, making it more aligned with the perovskite. This alignment enhances the efficiency of charge carrier transport. As the result, tin perovskite film quality is significantly improved,achieving a maximum power conversion efficiency approaching 12% with only an 8.3% efficiency loss after 1700 h of stability tests, which compares well with the state-of-the-art stability of tin-based perovskite solar cells.展开更多
In the acoustic detection process of buried non-metallic pipelines,the echo signal is often interfered by a large amount of noise,which makes it extremely difficult to effectively extract useful signals.An denoising a...In the acoustic detection process of buried non-metallic pipelines,the echo signal is often interfered by a large amount of noise,which makes it extremely difficult to effectively extract useful signals.An denoising algorithm based on empirical mode decomposition(EMD)and wavelet thresholding was proposed.This method fully considered the nonlinear and non-stationary characteristics of the echo signal,making the denoising effect more significant.Its feasibility and effectiveness were verified through numerical simulation.When the input SNR(SNRin)is between-10 dB and 10 dB,the output SNR(SNRout)of the combined denoising algorithm increases by 12.0%-34.1%compared to the wavelet thresholding method and by 19.60%-56.8%compared to the EMD denoising method.Additionally,the RMSE of the combined denoising algorithm decreases by 18.1%-48.0%compared to the wavelet thresholding method and by 22.1%-48.8%compared to the EMD denoising method.These results indicated that this joint denoising algorithm could not only effectively reduce noise interference,but also significantly improve the positioning accuracy of acoustic detection.The research results could provide technical support for denoising the echo signals of buried non-metallic pipelines,which was conducive to improving the acoustic detection and positioning accuracy of underground non-metallic pipelines.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12002156,11972185,12372136)Research Fund of State Key Laboratory of Mechanics and Control for Aerospace Structures(Grant No.MCMS-I-0222K01)。
文摘While the moisture content of soil affects significantly the blast impulse of shallow buried explosives,the role of surface-covering water(SCW)on soil in such blast impulse remains elusive.A combined experimental and numerical study has been carried out to characterize the effect of SCW on transferred impulse and loading magnitude of shallow buried explosives.Firstly,blast tests of shallow buried explosives were conducted,with and without the SCW,to quantitatively assess the blast loading impulse.Subsequently,finite element(FE)simulations were performed and validated against experimental measurement,with good agreement achieved.The validated FE model was then employed to predict the dynamic response of a fully-clamped metallic circular target,subjected to the explosive impact of shallow buried explosives with SCW,and explore the corresponding physical mechanisms.It was demonstrated that shallow buried explosives in saturated soil generate a greater impulse transferred towards the target relative to those in dry soil.The deformation displacement of the target plate is doubled.Increasing the height of SCW results in enhanced center peak deflection of the loaded target,accompanied by subsequent fall,due to the variation of deformation pattern of the loaded target from concentrated load to uniform load.Meanwhile,the presence of SCW increases the blast impulse transferred towards the target by three times.In addition,there exists a threshold value of the burial depth that maximizes the impact impulse.This threshold exhibits a strong sensitivity to SCW height,decreasing with increasing SCW height.An empirical formula for predicting threshold has been provided.Similar conclusions can be drawn for different explosive masses.The results provide technical guidance on blast loading intensity and its spatial distribution considering shallow buried explosives in coast-land battlefields,which can ultimately contribute to better protective designs.
基金National Natural Science Foundation of China under Grant Nos.52078386 and 52308496SINOMACH Youth Science and Technology Fund under Grant No.QNJJ-PY-2022-02+2 种基金Young Elite Scientists Sponsorship Program under Grant No.BYESS2023432Fund of State Key Laboratory of Precision Blasting and Hubei Key Laboratory of Blasting Engineering,Jianghan University under Grant No.PBSKL2023A9Fund of China Railway Construction Group Co.,Ltd.under Grant No.LX19-04b。
文摘Strong surface impact will produce strong vibration,which will pose a threat to the safety of nearby buried pipelines and other important lifeline projects.Based on the verified numerical method,a comprehensive numerical parameter analysis is conducted on the key influencing factors of the vibration isolation hole(VIH),which include hole diameter,hole net spacing,hole depth,hole number,hole arrangement,and soil parameters.The results indicate that a smaller ratio of net spacing to hole diameter,the deeper the hole,the multi-row hole,the hole adoption of staggered arrangements,and better site soil conditions can enhance the efficiency of the VIH barrier.The average maximum vibration reduction efficiency within the vibration isolation area can reach 42.2%.The vibration safety of adjacent oil pipelines during a dynamic compaction projection was evaluated according to existing standards,and the measurement of the VIH was recommended to reduce excessive vibration.The single-row vibration isolation scheme and three-row staggered arrangement with the same hole parameters are suggested according to different cases.The research findings can serve as a reference for the vibration safety analysis,assessment,and control of adjacent underground facilities under the influence of strong surface impact loads.
文摘As one of the important components of high-effi-ciency perovskite/silicon series devices,wide-bandgap(WBG)perovskite solar cells(PSCs)have been suffering from serious carrier transport barriers and huge open-circuit voltage deficit de-rived from non-radiative recombination,especial-ly at the buried interface that are often overlooked.Herein,we combined cationic and anion passiva-tion strategies via ammonium tetra-n-butyl tetrafluoroborate(TBABF_(4))pre-treating the buried interface.Theoretical calculation predicts that the tetrabutylammonium(TBA^(+))organic cations and(tetrafluoroborate)BF_(4)^(−)anions can easily interact with charged interfacial defect.Characterizations further confirm the enhance-ment of carrier transport performance and decrease in defect density upon TBABF4 pre-treat-ment.Consequently,a power conversion efficiency of 21.35%with an ultrahigh filling factor of 84.12%is obtained for 1.68 eV-WBG inverted PSCs.In addition,the device with TBABF4 pre-treatment demonstrates excellent shelf,thermal,and operational stability.
基金Supported by the Hainan Provincial Science and Technology Special Project(ZDYF2025GXJS013)CNOOC Zhanjiang Branch Project(CCL2023ZJFN0540).
文摘Based on drilling,mud logging,core,seismic and imaging logging data,this paper studies the identification and evolution process of negative inversion structures in the Carboniferous buried hills in the No.1 and No.2 fault zones of Weixinan Sag,Beibu Gulf Basin,China,and reveals the controls of these structures on high-quality reservoirs.The No.2 fault zone develops significant negative inversion structures in the Carboniferous buried hills,as a result of multi-stage transformations of compressive-tensile stress fields in the period from the Late Hercynian to the Himalayan.The Hercynian carbonates laid the material basis for the formation of high-quality reservoirs.The negative inversion structures mainly control the development of high-quality reservoirs in buried hills through:(1)creating large-scale fractures to increase reservoir space and improve oil-gas flow pathways;(2)regulating stratigraphic differential denudation to highlight dominant lithology for later reservoir transformation;(3)shaping the paleogeomorphological highlands to provide favorable conditions for superficial karstification.The negative inversion structures form a high-quality,composite reservoir space with the synergistic existence of superficial dissolution fractures/cavities and burial-enhanced karst systems through the coupling of fracture network creation,formation denudation screening and multi-stage karst transformation.The research results have guided the breakthrough of the first exploratory well with a daily oil production over 1000 m^(3)in carbonate buried-hill reservoir in the Beibu Gulf Basin,and provide referential geological basis for finding more reserves and achieving higher production in the Carboniferous buried hills in the Weixinan Sag.
基金financial support from the National Natural Science Foundation of China(Grant No.U2244222,42576244,42072324,42442603)the Guangzhou Basic and Applied Basic Research Foundation(Grant No.202201011367,202201011487).
文摘Weijia Guyot,located in the western Pacific Ocean,has become a research focus due to its abundant cobalt-rich ferromanganese(Fe-Mn)crusts.While most studies on Fe-Mn crusts on seamounts have focused on the exposed variety,less attention has been paid to potential buried crusts.This study presents a preliminary geochemical and chronological study of buried Fe-Mn crusts at Weijia Guyot.The findings suggest that these buried crusts began to form around 57.5 Ma and ceased growing at approximately 46.3 Ma.Following the formation of Weijia Guyot through volcanic eruption,it did not experience continuous and steady subsidence to its current depth.Instead,an exhumation process took place from deep to shallow depths between 46.3 and 11.6 Ma.This process brought the Fe-Mn crusts into shallow water environments,halting their growth.During this time,Weijia Guyot was located near the equatorial Pacific Ocean and was exposed to an extended period of phosphatization.This exposure led to a depletion of key metallogenic elements,such as Co,Ni and Cu,within the Fe-Mn crusts,while P2O5 and CaO levels increased significantly.Since the Middle Miocene,the crusts have been progressively buried by pelagic sediments.
文摘The BZ oilfield in the Bohai Sea is a rare,highly volatile reservoir with fractures in the metamorphic rocks of buried hills.Clarifying the mechanism of gas injection for improving oil recovery and determining the optimal way to deploy injection-production well networks are critical issues that must be urgently addressed for efficient oilfield development.Experimental research on the mixed-phase displacement mechanism through gas injection into indoor formation fluids was conducted to guide the efficient development of gas injection in oil fields.We established a model of dual-medium reservoir composition and researched the deployment strategy for a three-dimensional well network for gas injection development.The coupling relationship between key influencing factors of the well network and fracture development was also quantitatively analyzed.The results show that the solubility of the associated gas and strong volatile oil system injected into the BZ oilfield is high.This high solubility demonstrates a mixed-phase displacement mechanism involving intermediate hydrocarbons,dissolution and condensation of medium components,and coexistence of extraction processes.Injecting gas and crude oil can achieve a favorable mixing effect when the local formation pressure is greater than 35.79 MPa.Associated gas reinjection is recommended to supplement energy for developing the highly volatile oil reservoirs in the fractured buried hills of the BZ oilfield.This recommendation involves fully utilizing the structural position and gravity-assisted oil displacement mechanism to deploy an injection-production well network.Gas injection points should be constructed at the top of high areas,and oil production points should be placed at the middle and lower parts of low areas.This approach forms a spatial threedimensional well network.By adopting high inclination well development,the oil production well forms a 45°angle with the fracture direction,which increases the drainage area and enhances single-well production capacity.The optimal injection-production well spacing along the fracture direction is approximately 1000 m,while the reasonable well spacing in the vertical fracture direction is approximately 800 m.The research results were applied to the development practice of the buried hills in the BZ oilfield,which achieved favorable development results.These outcomes provide a valuable reference for the formulation of development plans and efficient gas injection development in similar oil and gas fields in buried hills.
基金financially supported by the National Key R&D Program of China(2022YFB4200303 to D.Zhao)the National Natural Science Foundation of China(62174112,52461160298 to D.Zhao and E30853YM19 to C.Xiao)+2 种基金the Natural Science Foundation of Sichuan Province(2024NSFSC1011 to C.Chen)the Fundamental Research Funds for the Central Universities(YJ2021157 to C.Chen)the Engineering Featured Team Fund of Sichuan University(2020SCUNG102 to D.Zhao)。
文摘Numerous defects at the buried interface of perovskite film and the exacerbated oxidation and degradation of tin-lead(Sn-Pb)perovskites induced by poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS),due to its hygroscopic and acidic nature,limit performance improvement of SnPb perovskite solar cells(PSCs).To address these issues,1-Ethyl-3-Guanidinothiourea-Hydrochloride(EGH)was employed as a multifunctional modifier at the PEDOT:PSS/perovskite interface to regulate the buried interface behaviors of Sn-Pb PSCs.EGH can not only passivate the defects of the perovskite buried interface and regulate the work function of PEDOT:PSS for a more matched interface energy level,but also prevent the perovskite film from erosion damage by the acidic PEDOT:PSS for a more stable PEDOT:PSS/perovskite interface.Moreover,the interfacial charge transport dynamics were significantly improved by obviously suppressing interfacial non-radiative recombination losses.As a consequence,EGH-tailored 1.25 eV Sn-Pb PSCs yielded a champion PCE of 23.20%,featuring enhanced long-term stability.
基金supported by the National Natural Science Foundation of China(Grant numbers 52208392,52068044,and 52168058)China Post-doctoral Science Foundation(Grant number 2021M693843)+1 种基金Tianyou Youth Talent Lift Program of Lanzhou Jiaotong University(Grant number 1520260306)Key Laboratory of Road and Bridge and Underground Engineering of Gansu Province(Grant number GSDQ-KF2020-5).
文摘Uneven terrain significantly increases the seismic risk of tunnels in loess deposits.To investigate the variations in optimal intensity measures(IMs)for shallowly buried loess tunnels considering biased terrain,nonlinear dynamic analyses were conducted to obtain seismic responses validated by the actual damage pattern.Then IMs were evaluated based on the automatic calculation of the time history damage index fulfilled by a compiled Python program.Results showed that the plastic strain zone progressively developed and extended from the vault to the central slope surface with increasing seismic intensities,ultimately causing shear failure to the tunnel.For IMs at the slope top,peak ground velocity(PGV)(ζ=0.15),velocity spectrum intensity(VSI)(ζ=0.20),and peak spectrum velocity(PSv)(ζ=0.22)were all suitable for seismic fragility assessment.The VSI(ζ=0.17)was optimal,followed by PGV(ζ=0.19)and PSv(ζ=0.2)for those at the slope foot.Acceleration-related IMs were more sensitive to terrain variation.Comparative analyses demonstrated smaller damage probabilities for the IMs at the slope top than those at the slope foot under the same intensity level.The impact of unfavorable terrain on tunnels was accentuated as those located in uneven mountainous regions became more vulnerable to ground shaking.
基金supported by Photon Science Research Center For Carbon Dioxide,Project of the National Natural Science Foundation of China(22332003)supported by the National Natural Science Foundation of China(12175298,12075309)+10 种基金the National Natural Science Foundation of China(62404176)Shanghai Science and Technology Innovation Action Plan(22JC1403800)Shanghai Municipal Science and Technology Commission(23JC1403300)2022 Self Deployed Instrument Design Project of Shanghai Advanced Research Institutethe Research Grant from the Shanghai Sailing Program(17YF1423700)Shanghai Municipal Commission for Science and Technology(20ZR1464100)Youth Innovation Promotion Association CAS(2021284)Fudan University Talent Introduction Projectthe support from the China Postdoctoral Science Foundation(2023M742732)the Postdoctoral Fellowship Program of CPSF(GZC20241303)the Fundamental Research Funds for the Central Universities(XJSJ24100)。
文摘Perovskite solar cells(PSC)are considered as a promising photovoltaic technology due to their low cost and high efficiency exceeding 26.8%.Ultra-lightweight flexible perovskite solar cells(FPSCs)can be applied to many fields such as architecture and portable devices.Although the photovoltaic conversion efficiency(PCE)of FPSC has exceeded 24%in the past few years,further application of FPSC is constrained by the challenges posed by limitation of critical material components.Here,we discussed recent research progress of key FPSC materials,mechanical endurance,low-temperature fabrication,etc.With the advantages of high brightness,collimation and resolution,we specially introduced the application of synchrotron radiation grazing incidence wide-angle X-ray scattering(GIWAXS)to directly observe the perovskite buried interface structure and corresponding mechanical stability of FPSCs without any damage.Finally,we summarize the challenges and propose an outlook about the large-scale preparation of efficient and stable FPSC modules.
基金financially supported by the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(Chengdu University of Technology)(Grant No.SKLGP2020Z007)。
文摘Deeply buried mountain tunnels are often exposed to the risk of rock bursts,which always cause serious damage to the supporting structures and threaten the safety of the engineers.Due to the limited data available,a suitable approach to predict the rockburst tendency at the preliminary stage becomes very important.In this study,an integrated methodology combining 3D initial stress inversion and rockburst tendency prediction was developed and subsequently applied to a case study of the Sangzhuling Tunnel on the Sichuan–Tibet Railway.The numerical modelling involved inverting the initial stress field using a multiple linear regression method.The tunnel excavation was simulated separately by FDM and DEM,based on a stress boundary condition from the inverted stress field.The comparative analysis demonstrates that the rockburst ratio calculated using DEM(76.70%)exhibits a slight increase compared to FDM(75.38%),and the rockburst location is consistent with the actual situation.This suggests that DEM is more suitable for simulating the stress redistribution during excavation in a jointed rock mass.The numerical simulation combined with the deviatoric stress approach effectively predicts rockburst tendency,meeting the engineering requirements.Despite its limitations,numerical simulation remains a reliable method for predicting rock bursts.
文摘Caves located in the buried hill reservoir of granite bedrock in Bongor Basin,Chad,are excessively small and cannot be identifi ed in conventional refl ection wave imaging profi les because their refl ection characteristics are suppressed by the strong refl ection of the weathering crust at the top of the buried hill.In contrast to refl ection wave imaging,which refl ects the refl ection characteristics of continuous interfaces,scattered wave imaging refl ects the reflection characteristics of discontinuous geological bodies.Scattering waves can be produced in the presence of discontinuous points,such as karst caves,fractures,and stratum vanishing points.Scattering imaging can accurately provide the location of discontinuous abnormal bodies,highlight the seismic reflection characteristics of caves with weak reflections,and eliminate continuous strong reflections to strengthen the ability of seismic data to distinguish discontinuous geological bodies and solve the inability of seismic data from conventional poststack refl ection wave imaging to identify small caves in buried hills.Three-parameter wavelet spectral decomposition technology is used to depict the boundary of caves accurately in accordance with the strong energy spectral characteristics of caves in the section of the scattering imaging seismic data of the granite bedrock buried hill reservoir.Compared with the attributes extracted from conventional refl ection wave poststack seismic data,those acquired from scattering imaging bodies are more reliable and consistent with the actual location of caves on boreholes and have higher resolution.For connected wells,the attributes extracted from the conventional poststack seismic data can only predict whether caves are developed,whereas those calculated from scattering imaging can not only predict whether caves are present but also refl ects the degree of cave development.On the plane,the attributes obtained from scattering imaging calculation are more consistent with the geological law of cave development.On the basis of this fi nding and in accordance with the results of the three-parameter wavelet spectral decomposition of scattering imaging seismic data,the degree of cave development is classifi ed,and the favorable location for reservoir development in the study area is identifi ed.This solution provides an eff ective way to improve the exploration accuracy of cave-type granite buried hill reservoirs.
基金supported by National Natural Science Foundation of China(42002293,52068019)Hainan Provincial Natural Science Foundation of China(520QN229,422RC599)+2 种基金Independent Innovation Fund Project of Tianjin University and Hainan University(KF2022⁃03)Scientific Research Startup Foundation of Hainan university(KYQD(2R)1969)Systematic Project of Key Laboratory of Geological Hazards on Three Gorges Reservoir Area(Three Gorges University),Ministry of Education(2020KDZ04).
文摘The chief objective of the article is to learn the spatial characteristics of stress distribution around a shallow buried cylinder Karst cave in limestone strata.Firstly,taking into account the geometry of limestone formations,and the characteristics of Karst geomorphology in China,a spatial axialsymmetrical hollow model was established.Concurrently,combining available work and the concept of elasticity,the boundary conditions are determined.Subsequently,Love displacement method was introduced,the expressions of stress components were gained.The diagram characteristics of each stress component are summarized,which are affected by various influencing factors.Finally,in order to prove the rationality of the general solution,numerical simulation was carried out on the basis of practical engineering,and the maximum error is less than 5%.Thus,the analytical solution could represent the spatial characteristics of stress distribution around a shallow buried cylinder Karst cave in limestone strata.
基金supported by Jiangsu provincial key R&D plan special fund(Social Development)project in China(No.BE2019606)a funding for Clinical Trials from the Nanjing Drum Tower Hospital,Affiliated Hospital of Medical School,Nanjing University(Nanjing,China,2024-LCYJ-PY-65).
文摘Various techniques have been described for reconstructing the skin of the penile shaft;however,no universally accepted standard exists for correcting buried penis in adults.We aimed to describe a new technique for correcting an adult-acquired buried penis through a diamond-shaped incision at the penopubic junction.We retrospectively analyzed data from patients treated with our technique between March 2019 and June 2023 in the Department of Andrology,Nanjing Drum Tower Hospital(Nanjing,China).Forty-two adult males with buried penises,with a mean(±standard deviation[s.d.])age of 26.6(±6.6)years,underwent surgery.All patients were obese,with an average(±s.d.)body mass index of 35.56(±3.23)kg m^(-2).In addition to phalloplasty,32 patients concurrently underwent circumcision,and 28 underwent suprapubic liposuction.The mean(±s.d.)duration of the operation was 98.02(±13.28)min.The mean(±s.d.)duration of follow-up was 6.71(±3.43)months.The length in the flaccid unstretched state postoperatively was significantly greater than that preoperatively(mean±s.d:5.55±1.19 cm vs 1.94±0.59 cm,P<0.01).Only minor complications,such as wound disruption(7.1%)and infection(4.8%),were observed.The mean(±s.d.)score of patient satisfaction was 4.02(±0.84)on a scale of 5.This technique provides excellent cosmetic and functional outcomes with a minimal risk of complications.However,additional clinical studies are needed to evaluate the long-term effects of this procedure.
基金support from the National Natural Science Foundation of China(Nos.42104043,42374081,and U2039208)the Fundamental Research Funds for the Institute of Geophysics,China Earthquake Administration(No.DQJB22R35).
文摘On August 6,2023,a magnitude MW5.5 earthquake struck Pingyuan County,Dezhou City,Shandong Province,China.This event was significant as no large earthquakes had been recorded in the region for over a century,and no active fault had been previously identified.This study collects 1309 P-wave arrival times and 866 S-wave arrival times from 74 seismic stations less than 200 km to the epicenter to constrain the spatial distribution of the mainshock and its 125 early aftershocks by the double difference earthquake relocation method,and selects 864 P-waveforms from 288 stations located within 800 km of the epicenter to constrain the focal mechanism solution of the mainshock through centroid moment tensor inversion.The relocation and the inversion indicate,the Pingyuan MW5.5 earthquake was caused by a rupture on a buried fault,likely an extensive segment of the Gaotang fault.This buried fault exhibited a dip of approximately 75°to the northwest,with a strike of 222°,similar to the Gaotang fault.The rupture initiated at the depth of 18.6 km and propagated upward and northeastward.However,the ground surface was not broken.The total duration of the rupture was~6.0 s,releasing the scalar moment of 2.5895×1017 N·m,equivalent to MW5.54.The moment rate reached the maximum only 1.4 seconds after the rupture initiation,and the 90%scalar moment was released in the first 4.6 s.In the first 1.4 seconds of the rupture process,the rupture velocity was estimated to be 2.6 km/s,slower than the local S-wave velocity.As the rupture neared its end,the rupture velocity decreased significantly.This study provides valuable insights into the seismic characteristics of the Pingyuan MW5.5 earthquake,shedding light on the previously unidentified buried fault responsible for the seismic activity in the region.Understanding the behavior of such faults is crucial for assessing seismic hazards and enhancing earthquake preparedness in the future.
基金This work was supported by the National Natural Science Foundation of China(62104136,22179051)the National Key Research and Development Program of China(2021YFE0111000)+3 种基金Project of Shandong Province Higher Educational Young Innovative Team(2022KJ218)China Postdoctoral Science Foundation(2023M732104)Qingdao Postdoctoral Funding Program(QDBSH20220201002)Postdoctoral Innovation Project of Shandong Province(SDCX-ZG-202303032).
文摘The buried interface in the perovskite solar cell(PSC)has been regarded as a breakthrough to boost the power conversion efficiency and stability.However,a comprehensive manipulation of the buried interface in terms of the transport layer,buried interlayer,and perovskite layer has been largely overlooked.Herein,we propose the use of a volatile heterocyclic compound called 2-thiopheneacetic acid(TPA)as a pre-buried additive in the buried interface to achieve cross-layer all-interface defect passivation through an in situ bottom-up infiltration diffusion strategy.TPA not only suppresses the serious interfacial nonradiative recombination losses by precisely healing the interfacial and underlying defects but also effectively enhances the quality of perovskite film and releases the residual strain of perovskite film.Owing to this versatility,TPA-tailored CsPbBr3 PSCs deliver a record efficiency of 11.23% with enhanced long-term stability.This breakthrough in manipulating the buried interface using TPA opens new avenues for further improving the performance and reliability of PSC.
基金the support of the National Natural Science Foundation of China(Nos.42207211,42202320 and 42172296)Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education,Tongji University(No.KLE-TJGE-G2304).
文摘Imaging the wave velocity field surrounding a borehole while drilling is a promising and urgently needed approach for extending the exploration range of the borehole point.This paper develops a drilling process detection(DPD)system consisting of a multifunctional sensor and a pilot geophone installed at the top of the drilling rod,geophones at the tunnel face,a laser rangefinder,and an onsite computer.A weighted adjoint-state first arrival travel time tomography method is used to invert the P-wave velocity field of rock mass while borehole drilling.A field experiment in the ongoing construction of a deep buried tunnel in southwestern China demonstrated the DPD system and the tomography method.Time-frequency analysis of typical borehole drilling detection data shows that the impact drilling source is a pulse-like seismic exploration wavelet.A velocity field of the rock mass in a triangular area defined by the borehole trajectory and geophone receiving line can be obtained.Both the borehole core and optical image validate the inverted P-wave velocity field.A numerical simulation of a checkerboard benchmark model is used to test the tomography method.The rapid convergence of the misfits and consistent agreement between the inverted and observed travel times validate the P-wave velocity imaging.
基金Supported by the China National Offshore Oil Corporation Project(KJGG2022--0302)。
文摘Based on the data from 3D seismic surveys,drilling,sidewall coring,thin sections,and tests,this paper analyzes Meso-Cenozoic geotectonic dynamics,buried-hill reservoir characteristics,and differential enrichment patterns of oil and gas in the buried hills,as well as case studies of typical reservoirs,to systematically discuss the conditions required for the formation of buried-hills and reservoirs and accumulations in the large oil and gas fields in deep to ultra-deep composite buried hills in the Bohai Sea..The key findings are as follows.First,deep to ultra-deep composite buried hills developed in the offshore Bohai Bay Basin primarily due to the double-episode destruction of the North China Craton in the Yanshanian and Himalayan.The Tanlu Fault's activity and the destruction of the North China Craton worked together to create the destruction center,which moved and converged episodically from the Bohai Bay Basin's margins towards the Bozhong Sag.This led to the formation of two development zones for composite buried hills and an orderly process of mountain-building within the offshore Bohai Bay Basin and subsequently two development zones for composite buried hills,i.e.the middle and inner rim zones within the Bozhong Depression.Second,under the coupling of favorable lithologies and multi-stage structures,the middle and inner rim zones are favorable for the formation of reservoirs in fluid dissolution-pore/fracture zones underlying the weathering crust.Third,Massive hydrocarbons were produced along the middle and inner rim zones during the Episode Ⅱ craton destruction,which caused overpressure.These hydrocarbons then moved to and accumulated in the composite buried hills.Excellent conditions for the accumulation of hydrocarbons are still present in the interior and lower portions of these buried hills.These results encourage a change in buried hill research to investigate composite buried hills in three dimensions.It should be noted that the multi-stage volcanic structures in the inner rim zone of the Sag and the deep to ultra-deep composite buried hill interiors in the middle rim zone are significant successor areas for further Bohai Sea exploration.
基金supported by the National Natural Science Foundation of China(22379010,22109166,22309191)Chinese Academy of Sciences。
文摘CsPbI_(2)Br perovskite solar cells(PSCs)have drawn tremendous attention due to their suitable bandgap,excellent photothermal stability,and great potential as an ideal candidate for top cells in tandem solar cells.However,the abundant defects at the buried interface and perovskite layer induce severe charge recombination,resulting in the open-circuit voltage(V_(oc))output and stability much lower than anticipated.Herein,a novel buried interface management strategy is developed to regulate interfacial carrier dynamics and CsPbI_(2)Br defects by introducing ammonium tetrafluoroborate(NH_(4)BF_(4)),thereby resulting in both high CsPbI_(2)Br crystallization and minimized interfacial energy losses.Specifically,NH_(4)^(+)ions could preferentially heal hydroxyl groups on the SnO_(2)surface and balance energy level alignment between SnO_(2)and CsPbI_(2)Br,enhancing charge transport efficiency,while BF_(4)^(-)anions as a quasi-halogen regulate crystal growth of CsPbI_(2)Br,thus reducing perovskite defects.Additionally,it is proved that eliminating hydroxyl groups at the buried interface enhances the iodide migration activation energy of CsPbI_(2)Br for strengthening the phase stability.As a result,the optimized CsPbI_(2)Br PSCs realize a remarkable efficiency of 17.09%and an ultrahigh V_(oc)output of 1.43 V,which is one of the highest values for CsPbI_(2)Br PSCs.
基金National Natural Science Foundation of China (62274094, 62175117)Natural Science Foundation of Jiangsu Higher Education Institutions (22KJB510011)+1 种基金Key Lab of Modern Optical Technologies of Education Ministry of China, Soochow University (KJS2260)Huali Talents Program of Nanjing University of Posts and Telecommunications。
文摘Buried interfacial voids have always been a notorious phenomenon observed in the fabrication of lead perovskite films. The existence of interfacial voids at the buried interface will capture the carrier, suppress carrier transport efficiencies, and affect the stability of photovoltaic devices. However, the impact of these buried interfacial voids on tin perovskites, a promising avenue for advancing lead-free photovoltaics, has been largely overlooked. Here, we utilize an innovative weakly polar solvent pretreatment strategy(WPSPS) to mitigate buried interfacial voids of tin perovskites. Our investigation reveals the presence of numerous voids in tin perovskites during annealing, attributed to trapped dimethyl sulfoxide(DMSO) used in film formation. The WPSPS method facilitates accelerated DMSO evaporation, effectively reducing residual DMSO. Interestingly, the WPSPS shifts the energy level of PEDOT:PSS downward, making it more aligned with the perovskite. This alignment enhances the efficiency of charge carrier transport. As the result, tin perovskite film quality is significantly improved,achieving a maximum power conversion efficiency approaching 12% with only an 8.3% efficiency loss after 1700 h of stability tests, which compares well with the state-of-the-art stability of tin-based perovskite solar cells.
基金supported by Nanchong Southwest Petroleum University Science and Technology Strategic Cooperation Project(Nos.23XNSYSX0022,23XNSYSX0026)Provincial Science and Technology Plan Project(No.2023ZHCG0020)Southwest Petroleum University Natural Science“Sailing Plan”Project(No.2023QHZ003)。
文摘In the acoustic detection process of buried non-metallic pipelines,the echo signal is often interfered by a large amount of noise,which makes it extremely difficult to effectively extract useful signals.An denoising algorithm based on empirical mode decomposition(EMD)and wavelet thresholding was proposed.This method fully considered the nonlinear and non-stationary characteristics of the echo signal,making the denoising effect more significant.Its feasibility and effectiveness were verified through numerical simulation.When the input SNR(SNRin)is between-10 dB and 10 dB,the output SNR(SNRout)of the combined denoising algorithm increases by 12.0%-34.1%compared to the wavelet thresholding method and by 19.60%-56.8%compared to the EMD denoising method.Additionally,the RMSE of the combined denoising algorithm decreases by 18.1%-48.0%compared to the wavelet thresholding method and by 22.1%-48.8%compared to the EMD denoising method.These results indicated that this joint denoising algorithm could not only effectively reduce noise interference,but also significantly improve the positioning accuracy of acoustic detection.The research results could provide technical support for denoising the echo signals of buried non-metallic pipelines,which was conducive to improving the acoustic detection and positioning accuracy of underground non-metallic pipelines.
