[Objectives]To explore the effect of continuous nursing model based on the Omaha system on stroke patients.[Methods]A total of 40 stroke patients in the inpatient department of the Rehabilitation Department of Affilia...[Objectives]To explore the effect of continuous nursing model based on the Omaha system on stroke patients.[Methods]A total of 40 stroke patients in the inpatient department of the Rehabilitation Department of Affiliated Hospital of Jinggangshan University were selected and divided into two groups by the random number table method.Patients in the control group were given routine nursing,and those of the observation group were given continuous nursing based on the Omaha system theory.The score of neurological impairment,daily living ability scale and the quality of life,as well as patients satisfaction rate before and after treatment were compared between the two groups.[Results]The score of neurological impairment,daily living activity ability and the quality of life,as well as patients nursing satisfaction rate in the observation group were significantly better than those of the control group,with statistical significance(P<0.05).[Conclusions]The continuous nursing model based on the Omaha system can significantly improve the neurological function of stroke patients,improve their quality of life and life ability,and promote their rehabilitation.展开更多
Carbon capture,utilization and storage (CCUS) is considered as a very important technology for mitigating global climate change.Carbon dioxide (CO2) injected into an underground reservoir will induce changes in its ph...Carbon capture,utilization and storage (CCUS) is considered as a very important technology for mitigating global climate change.Carbon dioxide (CO2) injected into an underground reservoir will induce changes in its physical properties and the migration of CO2 will be affected by many factors.Accurately understanding these changes and migration characteristics of CO2 is crucial for selecting a CCUS project site,estimating storage capacity and ensuring storage security.In this paper,the basic principles of nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) technologies are briefly introduced in the context of laboratory experiments related to CCUS.The types of NMR apparatus,experimental samples and testing approaches applied worldwide are discussed and analyzed.Then two typical NMR core analysis systems used in CCUS field and a self-developed high-pressure,low-field NMR rock core flooding experimental system are compared.Finally,a summary of the current deficiencies related to NMR applied to CCUS field is given and future research plans are proposed.展开更多
In the past two decades,research on C_(2)storage in coal seams and simultaneously enhanced coalbed methane recovery(ECBM)has attracted a lot of attention due to its win–win effect between greenhouse gas(C_(2))emissio...In the past two decades,research on C_(2)storage in coal seams and simultaneously enhanced coalbed methane recovery(ECBM)has attracted a lot of attention due to its win–win effect between greenhouse gas(C_(2))emission reduction and coalbed methane recovery enhancement.This paper presents an overview on the current status of research on C_(2)-ECBM in the past two decades,which involves C_(2)storage capacity evaluations,laboratory investigations,modelings and pilot tests.The current status shows that we have made great progress in the ECBM technology study,especially in the understanding of the ECBM mechanisms.However,there still have many technical challenges,such as the definition of unmineable coal seams for C_(2)storage capacity evaluation and storage site characterization,methods for C_(2)injectivity enhancement,etc.The low injectivity of coal seams and injectivity loss with C_(2)injection are the major technique challenges of ECBM.We also search several ways to promote the advancement of ECBM technology in the present stage,such as integrating ECBM with hydraulic fracturing,using a gas mixture instead of pure C_(2)for injection into coal seams and the application of ECBM to underground coal mines.展开更多
Carbon dioxide(CO2) capture and storage(CCS) is considered widely as one of promising options for CO2emissions reduction,especially for those countries with coal-dominant energy mix like China.Injecting and storing a ...Carbon dioxide(CO2) capture and storage(CCS) is considered widely as one of promising options for CO2emissions reduction,especially for those countries with coal-dominant energy mix like China.Injecting and storing a huge volume of CO2in deep formations are likely to cause a series of geomechanical issues,including ground surface uplift,damage of caprock integrity,and fault reactivation.The Shenhua CCS demonstration project in Ordos Basin,China,is the first and the largest full-chain saline aquifer storage project of CO2in Asia.The injection started in 2010 and ended in 2015.during which totally 0.3 million tonnes(Mt) CO2was injected.The project is unique in which CO2was injected into 18 sandstone formations simultaneously and the overlying coal seams will be mined after the injection stopped in 2015.Hence,intense geomechanical studies and monitoring works have been conducted in recent years,including possible damage resulting from the temperature difference between injected CO2and formations,injection induced stress and deformation change,potential failure mode and safety factor,interaction between coal mining and CO2geological storage,determination of injection pressure limit,and surface monitoring by the interferometric synthetic aperture radar(InSAR) technology.In this paper,we first described the background and its geological conditions of the Shenhua CCS demonstration project.Then,we gave an introduction to the coupled thermo-hydro-mechano-chemical(THMC) processes in CO2geological storage,and mapped the key geomechanical issues into the THMC processes accordingly.Next,we proposed a generalized geomechanical research flowchart for CO2geological storage projects.After that,we addressed and discussed some typical geomechanical issues,including design of injection pressure limit.CO2injection induced near-field damage,and interaction between CO2geological storage and coal mining,in the Shenhua CCS demonstration project.Finally,we concluded some insights to this CCS project.展开更多
Pore structure of porous media, including pore size and topology, is rather complex. In immiscible twophase displacement process, the capillary force affected by pore size dominates the two-phase flow in the porous me...Pore structure of porous media, including pore size and topology, is rather complex. In immiscible twophase displacement process, the capillary force affected by pore size dominates the two-phase flow in the porous media, affecting displacement results. Direct observation of the flow patterns in the porous media is difficult, and therefore knowledge about the two-phase displacement flow is insufficient. In this paper, a two-dimensional(2D) pore structure was extracted from a sandstone sample, and the flow process that CO_2 displaces resident brine in the extracted pore structure was simulated using the Navier eStokes equation combined with the conservative level set method. The simulation results reveal that the pore throat is a crucial factor for determining CO_2 displacement process in the porous media. The two-phase meniscuses in each pore throat were in a self-adjusting process. In the displacement process,CO_2 preferentially broke through the maximum pore throat. Before breaking through the maximum pore throat, the pressure of CO_2 continually increased, and the curvature and position of two-phase interfaces in the other pore throats adjusted accordingly. Once the maximum pore throat was broken through by the CO_2, the capillary force in the other pore throats released accordingly; subsequently, the interfaces withdrew under the effect of capillary fore, preparing for breaking through the next pore throat.Therefore, the two-phase displacement in CO_2 injection is accompanied by the breaking through and adjusting of the two-phase interfaces.展开更多
It is important to understand the process of multiphase carbon dioxide(CO_(2))leakage in faults for the risk assessment of carbon capture and storage(CCS).To quantitatively characterize the CO_(2)leakage process in th...It is important to understand the process of multiphase carbon dioxide(CO_(2))leakage in faults for the risk assessment of carbon capture and storage(CCS).To quantitatively characterize the CO_(2)leakage process in the fault,pressure sensors,fiber Bragg grating(FBG)temperature and strain sensors were simultaneously used to monitor CO_(2)leakage in the fault.Ten experiments were carried out,including five groups of gaseous CO_(2)leakage tests with initial pressures of 1-5 MPa and five groups of liquid CO_(2)leakage tests with initial pressures of 6-10 MPa.The results indicate that when liquid CO_(2)leaked with an initial pressure of 7-10 MPa,the pressure and temperature of CO_(2)dropped rapidly in the first few seconds and then remained unchanged.The behavior that CO_(2)continues to leak while maintaining temperature and pressure unchanged is defined as“temporary pseudo-sealing(TPS)”behavior,which continues for the first 1/3 of the leakage period.However,this TPS behavior did not occur in gaseous CO_(2)leakage.If only the pressure and temperature data were used to evaluate whether CO_(2)leakage occurred,we would misjudge the risk of leakage in CCS projects during the TPS period.The causes and conditions of TPS behavior were further studied experimentally.The results show that:(1)TPS behavior is caused by the phase transition energy generated when liquid CO_(2)leaks.(2)The condition for TPS behavior is a small leak aperture(0.2 mm).Only a small leakage rate can make the phase transition energy and pressure change from a dynamic equilibrium,and(3)The compression zone caused by the Bernoulli effect and fault“barrier”could reduce the CO_(2)leakage rate and further promote the occurrence of TPS behavior.This study provides technical and theoretical support for the quantitative characterization of the CO_(2)leakage process in faults of CCS projects.展开更多
Efficient electron transport layers(ETLs)not only play a crucial role in promoting carrier separation and electron extraction in perovskite solar cells(PSCs)but also significantly affect the process of nucleation and ...Efficient electron transport layers(ETLs)not only play a crucial role in promoting carrier separation and electron extraction in perovskite solar cells(PSCs)but also significantly affect the process of nucleation and growth of the perovskite layer.Herein,crystalline polymeric carbon nitrides(cPCN)are introduced to regulate the electronic properties of SnO_(2) nanocrystals,resulting in cPCN-composited SnO_(2)(SnO_(2)-cPCN)ETLs with enhanced charge transport and perovs-kite layers with decreased grain boundaries.Firstly,SnO_(2)-cPCN ETLs show three times higher electron mobility than pristine SnO_(2) while offering better energy level alignment with the perovskite layer.The SnO_(2)-cPCN ETLs with decreased wettability endow the perovskite films with higher crystallinity by retarding the crystallization rate.In the end,the power conversion efficiency(PCE)of planar PSCs can be boosted to 23.17%with negligible hysteresis and a steady-state efficiency output of 21.98%,which is one of the highest PCEs for PSCs with modified SnO_(2) ETLs.SnO_(2)-cPCN based devices also showed higher stability than pristine SnO_(2),maintaining 88%of the initial PCE after 2000 h of storage in the ambient environment(with controlled RH of 30%±5%)without encapsulation.展开更多
CO_(2) geological utilization and storage(CGUS)is an important technology to achieve a deep cut of global CO_(2) emissions.CO_(2) leakage from the subsurface may impair the performance of CGUS projects,and the CO_(2) ...CO_(2) geological utilization and storage(CGUS)is an important technology to achieve a deep cut of global CO_(2) emissions.CO_(2) leakage from the subsurface may impair the performance of CGUS projects,and the CO_(2) leakage through wellbores is the most common leakage pathway.This paper proposes a workflow for wellbore CO_(2) leakage risk management,and the workflow consists of the following steps:i)leakage risk identification;ii)leakage risk evaluation;iii)leakage risk monitoring;iv)leakage handling.Representative approaches in each step of the workflow are systematically reviewed.Key challenges of wellbore CO_(2) leakage risk management include:lack of effective detection and evaluation approaches to tackle the CO_(2) leakage risk induced by cement failure;lack of low-cost acid resistance alloys and CO_(2)-resistant cement;lack of automated monitoring systems that could enable automated shutdowns of the wellbore whenever certain warning criteria are met.展开更多
Objective: The purpose of this study was to investigate the effect of Laggera alata flavonen(LAF) on the inhibiting effect of human ovarian cancer HO-8910 cells proliferation and its possible mechanism in vitro. Metho...Objective: The purpose of this study was to investigate the effect of Laggera alata flavonen(LAF) on the inhibiting effect of human ovarian cancer HO-8910 cells proliferation and its possible mechanism in vitro. Methods: Human ovarian cancer HO-8910 cells were cultured in vitro. Inhibitory effect of LAF on the viability of HO-8910 cells was evaluated by the MTT assay. Apoptotic effect of different concentrations of LAF on HO-8910 cells was assessed by AO/EB staining and FCM with propidium iodide(PI) staining. Expression of proteins related to apoptosis was analyzed by Western blot. Results: LAF significantly inhibited the viability of HO-8910 cells proliferation in a dose-dependent and time-dependent manner, there were statistical significance compared with NS group(P < 0.05), and the IC50 was 4.28 μg/mL for 48 h. The cells treated with LAF showed typical morphological change and apoptotic rate increased by FCM in a dose-dependent, and there was notable difference compared with NS group(P < 0.05). Western blot showed that expression of Fas, caspase-8, tBid and Cyto-c proteins were up-regulated after treatment with LAF for 48 h in a concentration dependent. Conclusion: LAF could inhibit HO-8910 cells proliferation and induce apoptosis, which may be through the pathway of death receptor in vitro.展开更多
Quantum mechanics shows superiority than classical mechanics in many aspects and quantum entanglement plays an essential role in information processing and some computational tasks such as quantum teleportation(QT).QT...Quantum mechanics shows superiority than classical mechanics in many aspects and quantum entanglement plays an essential role in information processing and some computational tasks such as quantum teleportation(QT).QT was proposed to transmit the unknown states,in which EPR pairs,the entangled states,can be used as quantum channels.In this paper,we present two simple schemes for teleporting a product state of two arbitrary single-particle and an arbitrary two-particle pure entangled state respectively.Alice and Bob have shared an entangle state.Two Bell states are used as quantum channels.Then after Alice measuring her qubits and informing Bob her measurement results,Bob can perfectly reconstruct the original state by performing corresponding unitary operators on his qubits.It shown that a product state of two arbitrary single-particle and an arbitrary two-particle pure entangled state can be teleported perfectly,i.e.the success probabilities of our schemes are both 1.展开更多
Closed-cell aluminum foam was shot peened at different processing time (0 s, 5 s, 10 s, and 20 s), the intensity was the 0.12 mmA. The X-ray diffraction results showed that the reflections became weakened obviously wi...Closed-cell aluminum foam was shot peened at different processing time (0 s, 5 s, 10 s, and 20 s), the intensity was the 0.12 mmA. The X-ray diffraction results showed that the reflections became weakened obviously with the shot peened time increased. Combined with Popa model and lognormal distribute model, the surface microstructure of closed-cell aluminum foam was inves-tigated by using the Rietveld whole pattern fitting analysis method. The results revealed that domain size and microstrain fluctuated along different reflection directions after shot peened, which attributed to the random and anisotropic deformation direction. With the shot peened processing time prolonged, a decrease in domain size and an increase in microstrain were also observed. Moreover, the corrosion behavior of closed-cell aluminum foam was studied by weight-loss test. The results indicated that corrosion properties of specimen subjected to shot peened processing was better than the unpeened specimens.展开更多
CONSPECTUS:Photoelectrochemical(PEC)water splitting is an appealing approach to the hydrogen evolution reaction since it converts sunlight in the form of hydrogen fuel,which has the potential to revolutionize the foss...CONSPECTUS:Photoelectrochemical(PEC)water splitting is an appealing approach to the hydrogen evolution reaction since it converts sunlight in the form of hydrogen fuel,which has the potential to revolutionize the fossil fuel-based energy systems of the modern society.In the last half century,progress has been made with respect to the material,synthesis,and system.Recent developments of multilayered photoelectrodes have made a breakthrough to improve the sunlight conversion efficiency and strengthen the physiochemical stability.The exploration of new materials for the functional layers of photoelectrodes offers a new opportunity for practical application.Among the emerging materials,metal-free species have shown superior properties,such as high stability,sustainability,and renewability.With respect to inorganic materials,their physiochemical properties can be readily regulated,including thermodynamics and kinetics,and thus increasing attention has been devoted.展开更多
More durable[with high impact force],lighter,and more compact flexible azo dye micropolarizers are attractive candidates for low-cost,simple polarization imaging systems.The liquid crystal polymer[LCP],as an emerging ...More durable[with high impact force],lighter,and more compact flexible azo dye micropolarizers are attractive candidates for low-cost,simple polarization imaging systems.The liquid crystal polymer[LCP],as an emerging material developed by photo-alignment technology,is a potential material for organizing the long-range ordered structure of azo dyes.However,little research has been done on LCP aligned azo dyes.This paper points out and solves a key problem that restricts the fabrication of high-precision arrays in guest[azo dye]-host[LCP]systems:the doping of dyes leads to disorder of the LCP during curing.After solving the problem,the relationship between the thickness of the LCP and the extinction ratio of the polarizing film was investigated,which effectively improved the extinction ratio.Alignment of azo dye molecules in the range of 2μm[0°-180°]and arrays of micropolarizers[0°,45°,90°,-45°]with 8μm×8μm pixel pitch was achieved by laser direct writing technology.The bending cycle test demonstrates the mechanical stability of the ultrathin flexible polarizer.The flexible patterned polarizer with robust chemical and mechanical stabilities provides a flexible way to capture the polarization of the light and highly integrated advanced flexible optoelectronic devices.展开更多
Ultrafine-grained(UFG)/nanocrystalline materials possess novel properties. Refining as-solidified grains of metals to the ultrafine and even nanometer scale by nanoparticles via slow cooling has been recently discover...Ultrafine-grained(UFG)/nanocrystalline materials possess novel properties. Refining as-solidified grains of metals to the ultrafine and even nanometer scale by nanoparticles via slow cooling has been recently discovered. Here, we report that microparticles(CrB and CrB_(2)) with surface nanofeatures can also enable ultrafine/nano grains via slow cooling. CrB/CrB_(2) microparticles, formed by coalescence of nanoparticles in Cu matrix, display surface nanofeatures, which induce substantial grain refinement and stabilization down to the ultrafine/nano scale. The UFG Cu/Cr B and Cu/CrB_(2) samples exhibit exceptional thermal stability, comparable to UFG Cu induced by nanoparticles, without coarsening after annealing at 600°C for 1 h. The microhardness, strengths, and Young's moduli of the Cu/Cr B and Cu/CrB_(2) samples are significantly enhanced over pure Cu. This discovery has great potential to advance the mass production UFG/nanocrystalline for widespread applications.展开更多
CO_(2)capture,utilization and storage(CCUS)is recognized as a uniquely important option in global efforts to control anthropogenic greenhouse-gas(GHG)emissions.Despite significant progress globally in advancing the ma...CO_(2)capture,utilization and storage(CCUS)is recognized as a uniquely important option in global efforts to control anthropogenic greenhouse-gas(GHG)emissions.Despite significant progress globally in advancing the maturity of the various component technologies and their assembly into full-chain demonstrations,a gap remains on the path to widespread deployment in many countries.In this paper,we focus on the importance of business models adapted to the unique technical features and sociopolitical drivers in different regions as a necessary component of commercial scale-up and how lessons might be shared across borders.We identify three archetypes for CCUS development-resource recovery,green growth and low-carbon grids-each with different near-term issues that,if addressed,will enhance the prospect of successful commercial deployment.These archetypes provide a framing mechanism that can help to translate experience in one region or context to other locations by clarifying the most important technical issues and policy requirements.Going forward,the archetype framework also provides guidance on how different regions can converge on the most effective use of CCUS as part of global deep-decarbonization efforts over the long term.展开更多
Conventional colorimetric enzyme-linked immunosorbent assay(ELISA)is a time-consuming laboratory assay that is not very sensitive and consumes a large amount of samples.Herein,the development of a reusable,cost-effect...Conventional colorimetric enzyme-linked immunosorbent assay(ELISA)is a time-consuming laboratory assay that is not very sensitive and consumes a large amount of samples.Herein,the development of a reusable,cost-effective,and eco-friendly poly(methyl methacrylate)(PMMA)/paper hybrid plug-and-play(PnP)device for high-sensitivity immunoassay by analyte enrichment and efficient passing-through washing has been reported.The PMMA device has multiple slots where a pre-patterned paper substrate can be inserted.The sample flows back-and-forth through a low-cost,3D paper substrate within the PMMA channels,thereby enhancing the amount of analyte adsorbed and dramatically increasing the sensitivity while decreasing the assay time.After the enrichment assay,the paper substrate can simply be pulled out of the device,and the results can be qualitatively viewed with the naked eye or scanned through a simple desktop scanner for quantitative analysis.The paper substrate can be replaced with a new substrate so that the device can be reused.The limits of detection(LODs)of 200pg/mL for immunoglobulin G(IgG)and 270 pg/mL for hepatitis B surface antigen(HBsAg)were obtained.This IgG assay is at least 10 times more sensitive than commercial ELISA kits.In addition,the PnP ELISA exhibited a significant increase in the linear dynamic range from 3 orders of magnitude in a common paper-based device to a wide range of six orders of magnitude in the PnP hybrid device.This reusable PnP device has great potential for the low-cost yet high-sensitivity detection of infectious diseases,cancers,and other important biomolecules.展开更多
Bone is a unique tissue that is capable of repairing itself after damage.However,there are certain instances of fractures and defects that require clinical intervention for proper alignment and healing.As with any imp...Bone is a unique tissue that is capable of repairing itself after damage.However,there are certain instances of fractures and defects that require clinical intervention for proper alignment and healing.As with any implant,careful consideration of the material used to create the implants to treat these problems is needed.If the incorrect material is chosen,the implants themselves can lead to bone fractures or defects,or bone healing may not take place at all.All three classes of biomaterials-metals,ceramics,and polymers-have been used in the treatment of both bone fractures and bone defects,and each has its own unique benefits and limitations for its applications.Furthermore,composites of these different materials have also been created to try to take advantage of all the different benefits offered by each different material.This review highlights different materials that have been used for the development of internal fixators and bone graft substitutes to treat fracture and bone defects as well as their limitations and needed future research.展开更多
基金Supported by the Science and Technology Planning Project of Ji'an City,Jiangxi Province(2020-32).
文摘[Objectives]To explore the effect of continuous nursing model based on the Omaha system on stroke patients.[Methods]A total of 40 stroke patients in the inpatient department of the Rehabilitation Department of Affiliated Hospital of Jinggangshan University were selected and divided into two groups by the random number table method.Patients in the control group were given routine nursing,and those of the observation group were given continuous nursing based on the Omaha system theory.The score of neurological impairment,daily living ability scale and the quality of life,as well as patients satisfaction rate before and after treatment were compared between the two groups.[Results]The score of neurological impairment,daily living activity ability and the quality of life,as well as patients nursing satisfaction rate in the observation group were significantly better than those of the control group,with statistical significance(P<0.05).[Conclusions]The continuous nursing model based on the Omaha system can significantly improve the neurological function of stroke patients,improve their quality of life and life ability,and promote their rehabilitation.
基金supported by the Open Research Fund of State Key Laboratory of Geomechanics and GeotechnicalEngineering, IRSM, CAS (Grant No. Z017002)the National Natural Science Foundation of China (Grant Nos. 41872210 and 41274111)financial support from the China-Australia Geological Storage of CO_2 (CAGS) Project funded by the Australian Government under the auspices of the China-Australia Joint Coordination Group on Clean Coal Technology
文摘Carbon capture,utilization and storage (CCUS) is considered as a very important technology for mitigating global climate change.Carbon dioxide (CO2) injected into an underground reservoir will induce changes in its physical properties and the migration of CO2 will be affected by many factors.Accurately understanding these changes and migration characteristics of CO2 is crucial for selecting a CCUS project site,estimating storage capacity and ensuring storage security.In this paper,the basic principles of nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) technologies are briefly introduced in the context of laboratory experiments related to CCUS.The types of NMR apparatus,experimental samples and testing approaches applied worldwide are discussed and analyzed.Then two typical NMR core analysis systems used in CCUS field and a self-developed high-pressure,low-field NMR rock core flooding experimental system are compared.Finally,a summary of the current deficiencies related to NMR applied to CCUS field is given and future research plans are proposed.
基金Supported by the National Natural Science Foundation of China(51104143).
文摘In the past two decades,research on C_(2)storage in coal seams and simultaneously enhanced coalbed methane recovery(ECBM)has attracted a lot of attention due to its win–win effect between greenhouse gas(C_(2))emission reduction and coalbed methane recovery enhancement.This paper presents an overview on the current status of research on C_(2)-ECBM in the past two decades,which involves C_(2)storage capacity evaluations,laboratory investigations,modelings and pilot tests.The current status shows that we have made great progress in the ECBM technology study,especially in the understanding of the ECBM mechanisms.However,there still have many technical challenges,such as the definition of unmineable coal seams for C_(2)storage capacity evaluation and storage site characterization,methods for C_(2)injectivity enhancement,etc.The low injectivity of coal seams and injectivity loss with C_(2)injection are the major technique challenges of ECBM.We also search several ways to promote the advancement of ECBM technology in the present stage,such as integrating ECBM with hydraulic fracturing,using a gas mixture instead of pure C_(2)for injection into coal seams and the application of ECBM to underground coal mines.
基金the National Natural Science Foundation of China(Grant No.41274111)the Shenhua Group(Grant No.CSCLC-03-JS-2014-08)the National Department Public Benefit Research Foundation of MLR,China(Grant No.201211063-4-1)
文摘Carbon dioxide(CO2) capture and storage(CCS) is considered widely as one of promising options for CO2emissions reduction,especially for those countries with coal-dominant energy mix like China.Injecting and storing a huge volume of CO2in deep formations are likely to cause a series of geomechanical issues,including ground surface uplift,damage of caprock integrity,and fault reactivation.The Shenhua CCS demonstration project in Ordos Basin,China,is the first and the largest full-chain saline aquifer storage project of CO2in Asia.The injection started in 2010 and ended in 2015.during which totally 0.3 million tonnes(Mt) CO2was injected.The project is unique in which CO2was injected into 18 sandstone formations simultaneously and the overlying coal seams will be mined after the injection stopped in 2015.Hence,intense geomechanical studies and monitoring works have been conducted in recent years,including possible damage resulting from the temperature difference between injected CO2and formations,injection induced stress and deformation change,potential failure mode and safety factor,interaction between coal mining and CO2geological storage,determination of injection pressure limit,and surface monitoring by the interferometric synthetic aperture radar(InSAR) technology.In this paper,we first described the background and its geological conditions of the Shenhua CCS demonstration project.Then,we gave an introduction to the coupled thermo-hydro-mechano-chemical(THMC) processes in CO2geological storage,and mapped the key geomechanical issues into the THMC processes accordingly.Next,we proposed a generalized geomechanical research flowchart for CO2geological storage projects.After that,we addressed and discussed some typical geomechanical issues,including design of injection pressure limit.CO2injection induced near-field damage,and interaction between CO2geological storage and coal mining,in the Shenhua CCS demonstration project.Finally,we concluded some insights to this CCS project.
基金funded by Key Laboratory of Coal-based CO_2 Capture and Geological Storage,Jiangsu Province,ChinaUS Advanced Coal Technology Consortium(No.2013 DFB60140-08)
文摘Pore structure of porous media, including pore size and topology, is rather complex. In immiscible twophase displacement process, the capillary force affected by pore size dominates the two-phase flow in the porous media, affecting displacement results. Direct observation of the flow patterns in the porous media is difficult, and therefore knowledge about the two-phase displacement flow is insufficient. In this paper, a two-dimensional(2D) pore structure was extracted from a sandstone sample, and the flow process that CO_2 displaces resident brine in the extracted pore structure was simulated using the Navier eStokes equation combined with the conservative level set method. The simulation results reveal that the pore throat is a crucial factor for determining CO_2 displacement process in the porous media. The two-phase meniscuses in each pore throat were in a self-adjusting process. In the displacement process,CO_2 preferentially broke through the maximum pore throat. Before breaking through the maximum pore throat, the pressure of CO_2 continually increased, and the curvature and position of two-phase interfaces in the other pore throats adjusted accordingly. Once the maximum pore throat was broken through by the CO_2, the capillary force in the other pore throats released accordingly; subsequently, the interfaces withdrew under the effect of capillary fore, preparing for breaking through the next pore throat.Therefore, the two-phase displacement in CO_2 injection is accompanied by the breaking through and adjusting of the two-phase interfaces.
基金The research was partially supported by the Major Project of Inner Mongolia Science and Technology(Grant No.2021ZD0034)the National Natural Science Foundation of China(Grant Nos.41872210 and 41274111)The equipment and methodology we have developed for this research have applied for a national invention patent(ZL 202110708668.1).
文摘It is important to understand the process of multiphase carbon dioxide(CO_(2))leakage in faults for the risk assessment of carbon capture and storage(CCS).To quantitatively characterize the CO_(2)leakage process in the fault,pressure sensors,fiber Bragg grating(FBG)temperature and strain sensors were simultaneously used to monitor CO_(2)leakage in the fault.Ten experiments were carried out,including five groups of gaseous CO_(2)leakage tests with initial pressures of 1-5 MPa and five groups of liquid CO_(2)leakage tests with initial pressures of 6-10 MPa.The results indicate that when liquid CO_(2)leaked with an initial pressure of 7-10 MPa,the pressure and temperature of CO_(2)dropped rapidly in the first few seconds and then remained unchanged.The behavior that CO_(2)continues to leak while maintaining temperature and pressure unchanged is defined as“temporary pseudo-sealing(TPS)”behavior,which continues for the first 1/3 of the leakage period.However,this TPS behavior did not occur in gaseous CO_(2)leakage.If only the pressure and temperature data were used to evaluate whether CO_(2)leakage occurred,we would misjudge the risk of leakage in CCS projects during the TPS period.The causes and conditions of TPS behavior were further studied experimentally.The results show that:(1)TPS behavior is caused by the phase transition energy generated when liquid CO_(2)leaks.(2)The condition for TPS behavior is a small leak aperture(0.2 mm).Only a small leakage rate can make the phase transition energy and pressure change from a dynamic equilibrium,and(3)The compression zone caused by the Bernoulli effect and fault“barrier”could reduce the CO_(2)leakage rate and further promote the occurrence of TPS behavior.This study provides technical and theoretical support for the quantitative characterization of the CO_(2)leakage process in faults of CCS projects.
基金P.G.acknowledges the financial support from the National Natural Science Foundation of China(Grant No.21975260).
文摘Efficient electron transport layers(ETLs)not only play a crucial role in promoting carrier separation and electron extraction in perovskite solar cells(PSCs)but also significantly affect the process of nucleation and growth of the perovskite layer.Herein,crystalline polymeric carbon nitrides(cPCN)are introduced to regulate the electronic properties of SnO_(2) nanocrystals,resulting in cPCN-composited SnO_(2)(SnO_(2)-cPCN)ETLs with enhanced charge transport and perovs-kite layers with decreased grain boundaries.Firstly,SnO_(2)-cPCN ETLs show three times higher electron mobility than pristine SnO_(2) while offering better energy level alignment with the perovskite layer.The SnO_(2)-cPCN ETLs with decreased wettability endow the perovskite films with higher crystallinity by retarding the crystallization rate.In the end,the power conversion efficiency(PCE)of planar PSCs can be boosted to 23.17%with negligible hysteresis and a steady-state efficiency output of 21.98%,which is one of the highest PCEs for PSCs with modified SnO_(2) ETLs.SnO_(2)-cPCN based devices also showed higher stability than pristine SnO_(2),maintaining 88%of the initial PCE after 2000 h of storage in the ambient environment(with controlled RH of 30%±5%)without encapsulation.
基金The authors are grateful for the funding support provided by the Key R&D Program of Inner Mongolia Province of China(2021ZD0034)National Natural Science Foundation of China(Grant No.U1967208 and 42172315)Science and Technology Plan Project of Sichuan Prov-ince(2022YFSY0018).
文摘CO_(2) geological utilization and storage(CGUS)is an important technology to achieve a deep cut of global CO_(2) emissions.CO_(2) leakage from the subsurface may impair the performance of CGUS projects,and the CO_(2) leakage through wellbores is the most common leakage pathway.This paper proposes a workflow for wellbore CO_(2) leakage risk management,and the workflow consists of the following steps:i)leakage risk identification;ii)leakage risk evaluation;iii)leakage risk monitoring;iv)leakage handling.Representative approaches in each step of the workflow are systematically reviewed.Key challenges of wellbore CO_(2) leakage risk management include:lack of effective detection and evaluation approaches to tackle the CO_(2) leakage risk induced by cement failure;lack of low-cost acid resistance alloys and CO_(2)-resistant cement;lack of automated monitoring systems that could enable automated shutdowns of the wellbore whenever certain warning criteria are met.
文摘Objective: The purpose of this study was to investigate the effect of Laggera alata flavonen(LAF) on the inhibiting effect of human ovarian cancer HO-8910 cells proliferation and its possible mechanism in vitro. Methods: Human ovarian cancer HO-8910 cells were cultured in vitro. Inhibitory effect of LAF on the viability of HO-8910 cells was evaluated by the MTT assay. Apoptotic effect of different concentrations of LAF on HO-8910 cells was assessed by AO/EB staining and FCM with propidium iodide(PI) staining. Expression of proteins related to apoptosis was analyzed by Western blot. Results: LAF significantly inhibited the viability of HO-8910 cells proliferation in a dose-dependent and time-dependent manner, there were statistical significance compared with NS group(P < 0.05), and the IC50 was 4.28 μg/mL for 48 h. The cells treated with LAF showed typical morphological change and apoptotic rate increased by FCM in a dose-dependent, and there was notable difference compared with NS group(P < 0.05). Western blot showed that expression of Fas, caspase-8, tBid and Cyto-c proteins were up-regulated after treatment with LAF for 48 h in a concentration dependent. Conclusion: LAF could inhibit HO-8910 cells proliferation and induce apoptosis, which may be through the pathway of death receptor in vitro.
基金The work is supported by the National Natural Science Foundation of China(Grant No.61672014)the National Cryptography Development Fund(Grant No.MMJJ20180109)+1 种基金the Natural Science Foundation of Guangdong Province(Grant No.2016A030313090)the Fundamental Research Funds for the Central Universities.
文摘Quantum mechanics shows superiority than classical mechanics in many aspects and quantum entanglement plays an essential role in information processing and some computational tasks such as quantum teleportation(QT).QT was proposed to transmit the unknown states,in which EPR pairs,the entangled states,can be used as quantum channels.In this paper,we present two simple schemes for teleporting a product state of two arbitrary single-particle and an arbitrary two-particle pure entangled state respectively.Alice and Bob have shared an entangle state.Two Bell states are used as quantum channels.Then after Alice measuring her qubits and informing Bob her measurement results,Bob can perfectly reconstruct the original state by performing corresponding unitary operators on his qubits.It shown that a product state of two arbitrary single-particle and an arbitrary two-particle pure entangled state can be teleported perfectly,i.e.the success probabilities of our schemes are both 1.
文摘Closed-cell aluminum foam was shot peened at different processing time (0 s, 5 s, 10 s, and 20 s), the intensity was the 0.12 mmA. The X-ray diffraction results showed that the reflections became weakened obviously with the shot peened time increased. Combined with Popa model and lognormal distribute model, the surface microstructure of closed-cell aluminum foam was inves-tigated by using the Rietveld whole pattern fitting analysis method. The results revealed that domain size and microstrain fluctuated along different reflection directions after shot peened, which attributed to the random and anisotropic deformation direction. With the shot peened processing time prolonged, a decrease in domain size and an increase in microstrain were also observed. Moreover, the corrosion behavior of closed-cell aluminum foam was studied by weight-loss test. The results indicated that corrosion properties of specimen subjected to shot peened processing was better than the unpeened specimens.
基金This work was supported by the National Natural Science Foundation of China(21961142019,22075047,U1905214,and 21861130353)the National Key R&D Program of China(2018YFA0209301)+1 种基金the 111 Project(D16008)the Chang Jiang Scholars Program of China(T2016147).
文摘CONSPECTUS:Photoelectrochemical(PEC)water splitting is an appealing approach to the hydrogen evolution reaction since it converts sunlight in the form of hydrogen fuel,which has the potential to revolutionize the fossil fuel-based energy systems of the modern society.In the last half century,progress has been made with respect to the material,synthesis,and system.Recent developments of multilayered photoelectrodes have made a breakthrough to improve the sunlight conversion efficiency and strengthen the physiochemical stability.The exploration of new materials for the functional layers of photoelectrodes offers a new opportunity for practical application.Among the emerging materials,metal-free species have shown superior properties,such as high stability,sustainability,and renewability.With respect to inorganic materials,their physiochemical properties can be readily regulated,including thermodynamics and kinetics,and thus increasing attention has been devoted.
基金supported by the Changsha Municipal Natural Science Foundation(No.kq2014059)the School-Enterprise Cooperation Project(No.900201900966)。
文摘More durable[with high impact force],lighter,and more compact flexible azo dye micropolarizers are attractive candidates for low-cost,simple polarization imaging systems.The liquid crystal polymer[LCP],as an emerging material developed by photo-alignment technology,is a potential material for organizing the long-range ordered structure of azo dyes.However,little research has been done on LCP aligned azo dyes.This paper points out and solves a key problem that restricts the fabrication of high-precision arrays in guest[azo dye]-host[LCP]systems:the doping of dyes leads to disorder of the LCP during curing.After solving the problem,the relationship between the thickness of the LCP and the extinction ratio of the polarizing film was investigated,which effectively improved the extinction ratio.Alignment of azo dye molecules in the range of 2μm[0°-180°]and arrays of micropolarizers[0°,45°,90°,-45°]with 8μm×8μm pixel pitch was achieved by laser direct writing technology.The bending cycle test demonstrates the mechanical stability of the ultrathin flexible polarizer.The flexible patterned polarizer with robust chemical and mechanical stabilities provides a flexible way to capture the polarization of the light and highly integrated advanced flexible optoelectronic devices.
文摘Ultrafine-grained(UFG)/nanocrystalline materials possess novel properties. Refining as-solidified grains of metals to the ultrafine and even nanometer scale by nanoparticles via slow cooling has been recently discovered. Here, we report that microparticles(CrB and CrB_(2)) with surface nanofeatures can also enable ultrafine/nano grains via slow cooling. CrB/CrB_(2) microparticles, formed by coalescence of nanoparticles in Cu matrix, display surface nanofeatures, which induce substantial grain refinement and stabilization down to the ultrafine/nano scale. The UFG Cu/Cr B and Cu/CrB_(2) samples exhibit exceptional thermal stability, comparable to UFG Cu induced by nanoparticles, without coarsening after annealing at 600°C for 1 h. The microhardness, strengths, and Young's moduli of the Cu/Cr B and Cu/CrB_(2) samples are significantly enhanced over pure Cu. This discovery has great potential to advance the mass production UFG/nanocrystalline for widespread applications.
文摘CO_(2)capture,utilization and storage(CCUS)is recognized as a uniquely important option in global efforts to control anthropogenic greenhouse-gas(GHG)emissions.Despite significant progress globally in advancing the maturity of the various component technologies and their assembly into full-chain demonstrations,a gap remains on the path to widespread deployment in many countries.In this paper,we focus on the importance of business models adapted to the unique technical features and sociopolitical drivers in different regions as a necessary component of commercial scale-up and how lessons might be shared across borders.We identify three archetypes for CCUS development-resource recovery,green growth and low-carbon grids-each with different near-term issues that,if addressed,will enhance the prospect of successful commercial deployment.These archetypes provide a framing mechanism that can help to translate experience in one region or context to other locations by clarifying the most important technical issues and policy requirements.Going forward,the archetype framework also provides guidance on how different regions can converge on the most effective use of CCUS as part of global deep-decarbonization efforts over the long term.
基金We would like to acknowledge the financial support from the National Institute of Allergy and Infectious Disease of the NIH(R21AI107415)the U.S.NSF-PREM program(DMR 1827745)+2 种基金the Philadelphia Foundation,and the Medical Center of the Americas Foundation.Financial support from the National Institute of General Medical Sciences of the NIH(SC2GM105584)the NIH RCMI Pilot grant,University of Texas(UT)System for the STARS awardthe University of Texas at El Paso(UTEP)for the IDR Program,Multidisciplinary Research Award Program(MRAP)and URI Program is also greatly acknowledged.
文摘Conventional colorimetric enzyme-linked immunosorbent assay(ELISA)is a time-consuming laboratory assay that is not very sensitive and consumes a large amount of samples.Herein,the development of a reusable,cost-effective,and eco-friendly poly(methyl methacrylate)(PMMA)/paper hybrid plug-and-play(PnP)device for high-sensitivity immunoassay by analyte enrichment and efficient passing-through washing has been reported.The PMMA device has multiple slots where a pre-patterned paper substrate can be inserted.The sample flows back-and-forth through a low-cost,3D paper substrate within the PMMA channels,thereby enhancing the amount of analyte adsorbed and dramatically increasing the sensitivity while decreasing the assay time.After the enrichment assay,the paper substrate can simply be pulled out of the device,and the results can be qualitatively viewed with the naked eye or scanned through a simple desktop scanner for quantitative analysis.The paper substrate can be replaced with a new substrate so that the device can be reused.The limits of detection(LODs)of 200pg/mL for immunoglobulin G(IgG)and 270 pg/mL for hepatitis B surface antigen(HBsAg)were obtained.This IgG assay is at least 10 times more sensitive than commercial ELISA kits.In addition,the PnP ELISA exhibited a significant increase in the linear dynamic range from 3 orders of magnitude in a common paper-based device to a wide range of six orders of magnitude in the PnP hybrid device.This reusable PnP device has great potential for the low-cost yet high-sensitivity detection of infectious diseases,cancers,and other important biomolecules.
文摘Bone is a unique tissue that is capable of repairing itself after damage.However,there are certain instances of fractures and defects that require clinical intervention for proper alignment and healing.As with any implant,careful consideration of the material used to create the implants to treat these problems is needed.If the incorrect material is chosen,the implants themselves can lead to bone fractures or defects,or bone healing may not take place at all.All three classes of biomaterials-metals,ceramics,and polymers-have been used in the treatment of both bone fractures and bone defects,and each has its own unique benefits and limitations for its applications.Furthermore,composites of these different materials have also been created to try to take advantage of all the different benefits offered by each different material.This review highlights different materials that have been used for the development of internal fixators and bone graft substitutes to treat fracture and bone defects as well as their limitations and needed future research.