Metal-free organic emitters,characterized by their thermally activated delayed fluorescence(TADF)properties,offer considerable promise for the creation of highly efficient organic light-emitting diodes(OLEDs).Recently...Metal-free organic emitters,characterized by their thermally activated delayed fluorescence(TADF)properties,offer considerable promise for the creation of highly efficient organic light-emitting diodes(OLEDs).Recently,Shao et al.presented a novel excited state intramolecular proton transfer(ESIPT)system BrA-HBI,demonstrating an emission quantum yield of up to 50%[Adv.Funct.Mater.32,2201256(2022)].However,many open issues cannot be answered solely by experimental means only and require detailed theoretical investigations.For instance,what causes the activation of TADF from the Keto*tautomer and leads to fluorescence quenching in the Enol^(*)form?Herein,we provide a theoretical investigation on the TADF mechanism of the BrA-HBI molecule by optimally tuned range-separated functionals.Our findings reveal that ESIPT occurs in the BrA-HBI molecule.Moreover,we have disclosed the reason for the fluorescence quenching of the Enol^(*)form and determined that the T_(2)state plays a dominant role in the TADF phenomenon.In addition,double hybrid density functionals method was utilized to verify the reliability of optimally tuned range separation functionals on the calculation of the TADF mechanism in BrA-HBI.These findings not only provide a theoretical reference for development of highly efficient organic light-emitting diodes,but also demonstrate the effectiveness of the optimally tuned range-separated functionals in predicting the luminescence properties of TADF molecules.展开更多
Based on the waterflooding development in carbonate reservoirs in the Middle East,in order to solve the problem of the poor development effects caused by commingled injection and production,taking the thick bioclastic...Based on the waterflooding development in carbonate reservoirs in the Middle East,in order to solve the problem of the poor development effects caused by commingled injection and production,taking the thick bioclastic limestone reservoirs of Cretaceous in Iran-Iraq as an example,this paper proposes a balanced waterflooding development technology for thick and complex carbonate reservoirs.This technology includes the fine division of development units by concealed baffles and barriers,the combination of multi well type and multi well pattern,and the construction of balanced water injection and recovery system.Thick carbonate reservoirs in Iran-Iraq are characterized by extremely vertical heterogeneity,development of multi-genesis ultra-high permeability zones,and highly concealed baffles and barriers.Based on the technologies of identification,characterization,and sealing evaluation for concealed baffles and barriers,the balanced waterflooding development technology is proposed,and three types of balanced waterflooding development modes/techniques are formed,namely,conventional stratigraphic framework,fine stratigraphic framework,and deepened stratigraphic framework.Numerical simulations show that this technology is able to realize a fine and efficient waterflooding development to recover,in a balanced manner,the reserves of thick and complex carbonate reservoirs in Iran and Iraq.The proposed technology provides a reference for the development optimization of similar reservoirs.展开更多
[Objectives]To investigate the effect and mechanism of Dachengqi Decoction and separated decoction on incomplete intestinal obstruction in rats.[Methods]80 healthy SD rats were selected to establish incomplete intesti...[Objectives]To investigate the effect and mechanism of Dachengqi Decoction and separated decoction on incomplete intestinal obstruction in rats.[Methods]80 healthy SD rats were selected to establish incomplete intestinal obstruction model by silk ligation.The dosage was 20 mL/kg for 3 d,and the damage index of ileocecal mucosa was analyzed;the morphology of ileocecal mucosa was observed by HE staining;the serum levels of IL-1α,IL-1β,IL-6,IL-18,Ach,NO,ET,IL-1,TNF-αand ultra-micro Na+-K+-ATPase were detected by ELISA.[Results]Compared with the model group,the mucosal damage index of Dachengqi Decoction and each separated decoction group decreased significantly(P<0.05);compared with the normal group and sham operation group,the serum level of IL-1,IL-6,TNF-αand other factors in the model group increased significantly(P<0.05);compared with the model group,the serum IL-1,IL-6 and TNF-αsecretion levels of rats in Dachengqi Decoction group and separated decoction group decreased(P<0.01).[Conclusions]Dachengqi Decoction and each separated decoction can effectively improve intestinal tissue pathological damage in the incomplete intestinal obstruction model rats,and reduce the inflammatory reaction in the rat body.展开更多
An investigation of the decoupled thermal–hydraulic analysis of a separated heat pipe spent fuel pool passive cooling system(SFS)is essential for practical engineering applications.Based on the principles of thermal ...An investigation of the decoupled thermal–hydraulic analysis of a separated heat pipe spent fuel pool passive cooling system(SFS)is essential for practical engineering applications.Based on the principles of thermal and mass balance,this study decoupled the heat transfer processes in the SFS.In accordance with the decoupling conditions,we modeled the spent fuel pool of the CAP1400 pressurized water reactor in Weihai and used computational fluid dynamics to explore the heat dissipation capacity of the SFS under different air temperatures and wind speeds.The results show that the air-cooled separated heat pipe radiator achieved optimal performance at an air temperature of 10℃ or wind speed of 8 m/s.Fitted equations for the equivalent thermal conductivity of the separated heat pipes with the wind speed and air temperature we obtained according to the thermal resistance network model.This study is instructive for the actual operation of an SFS.展开更多
This article outlines the development of downhole monitoring and data transmission technology for separated zone water injection in China.According to the development stages,the principles,operation processes,adaptabi...This article outlines the development of downhole monitoring and data transmission technology for separated zone water injection in China.According to the development stages,the principles,operation processes,adaptability and application status of traditional downhole data acquisition method,cable communications and testing technology,cable-controlled downhole parameter real-time monitoring communication method and downhole wireless communication technology are introduced in detail.Problems and challenges of existing technologies in downhole monitoring and data transmission technology are pointed out.According to the production requirement,the future development direction of the downhole monitoring and data transmission technology for separated zone water injection is proposed.For the large number of wells adopting cable measuring and adjustment technology,the key is to realize the digitalization of downhole plug.For the key monitoring wells,cable-controlled communication technology needs to be improved,and downhole monitoring and data transmission technology based on composite coiled tubing needs to be developed to make the operation more convenient and reliable.For large-scale application in oil fields,downhole wireless communication technology should be developed to realize automation of measurement and adjustment.In line with ground mobile communication network,a digital communication network covering the control center,water distribution station and oil reservoir should be built quickly to provide technical support for the digitization of reservoir development.展开更多
A recent article in the Opto-Electronic Advances(OEA)journal from Prof.Qian Chen and Prof.Chao Zuo’s group introduced a new and efficient 3D imaging system that captures high-speed images using deep learning-enabled ...A recent article in the Opto-Electronic Advances(OEA)journal from Prof.Qian Chen and Prof.Chao Zuo’s group introduced a new and efficient 3D imaging system that captures high-speed images using deep learning-enabled fringe projection profilometry(FPP).In this News&Views article,we explore potential avenues for future advancements,including expanding the measurement range through an extended number-theoretical approach,enhancing quality through the incorporation of horizontal fringes,and integrating data from other modalities to broaden the system's applications.展开更多
BACKGROUND It remains unclear whether laparoscopic multisegmental resection and ana-stomosis(LMRA)is safe and advantageous over traditional open multisegmental resection and anastomosis(OMRA)for treating synchronous c...BACKGROUND It remains unclear whether laparoscopic multisegmental resection and ana-stomosis(LMRA)is safe and advantageous over traditional open multisegmental resection and anastomosis(OMRA)for treating synchronous colorectal cancer(SCRC)located in separate segments.AIM To compare the short-term efficacy and long-term prognosis of OMRA as well as LMRA for SCRC located in separate segments.METHODS Patients with SCRC who underwent surgery between January 2010 and December 2021 at the Cancer Hospital,Chinese Academy of Medical Sciences and the Peking University First Hospital were retrospectively recruited.In accordance with the RESULTS LMRA patients showed markedly less intraoperative blood loss than OMRA patients(100 vs 200 mL,P=0.006).Compared to OMRA patients,LMRA patients exhibited markedly shorter postoperative first exhaust time(2 vs 3 d,P=0.001),postoperative first fluid intake time(3 vs 4 d,P=0.012),and postoperative hospital stay(9 vs 12 d,P=0.002).The incidence of total postoperative complications(Clavien-Dindo grade:≥II)was 2.9%and 17.1%(P=0.025)in the LMRA and OMRA groups,respectively,while the incidence of anastomotic leakage was 2.9%and 7.3%(P=0.558)in the LMRA and OMRA groups,respectively.Furthermore,the LMRA group had a higher mean number of lymph nodes dissected than the OMRA group(45.2 vs 37.3,P=0.020).The 5-year overall survival(OS)and disease-free survival(DFS)rates in OMRA patients were 82.9%and 78.3%,respectively,while these rates in LMRA patients were 78.2%and 72.8%,respectively.Multivariate prognostic analysis revealed that N stage[OS:HR hazard ratio(HR)=10.161,P=0.026;DFS:HR=13.017,P=0.013],but not the surgical method(LMRA/OMRA)(OS:HR=0.834,P=0.749;DFS:HR=0.812,P=0.712),was the independent influencing factor in the OS and DFS of patients with SCRC.CONCLUSION LMRA is safe and feasible for patients with SCRC located in separate segments.Compared to OMRA,the LMRA approach has more advantages related to short-term efficacy.展开更多
In this paper, we introduce a novel scheme for the separate training of deep learning-based autoencoders used for Channel State Information (CSI) feedback. Our distinct training approach caters to multiple users and b...In this paper, we introduce a novel scheme for the separate training of deep learning-based autoencoders used for Channel State Information (CSI) feedback. Our distinct training approach caters to multiple users and base stations, enabling independent and individualized local training. This ensures the more secure processing of data and algorithms, different from the commonly adopted joint training method. To maintain comparable performance with joint training, we present two distinct training methods: separate training decoder and separate training encoder. It’s noteworthy that conducting separate training for the encoder can pose additional challenges, due to its responsibility in acquiring a compressed representation of underlying data features. This complexity makes accommodating multiple pre-trained decoders for just one encoder a demanding task. To overcome this, we design an adaptation layer architecture that effectively minimizes performance losses. Moreover, the flexible training strategy empowers users and base stations to seamlessly incorporate distinct encoder and decoder structures into the system, significantly amplifying the system’s scalability. .展开更多
The efficiency of photocatalytic overall water splitting was mainly limited by the slow reaction kinetics of water oxidation.How to design effective surface active site to overcome the slow water oxidation reaction wa...The efficiency of photocatalytic overall water splitting was mainly limited by the slow reaction kinetics of water oxidation.How to design effective surface active site to overcome the slow water oxidation reaction was a major challenge.Here,we propose a strategy to accelerate surface water oxidation through the fabrication spatially separated double active sites.FeCoPi/Bi_(4)NbO_(8)Cl-OVs photocatalyst with spatially separated double active site was prepared by hydrogen reduction photoanode deposition method.Due to the high matching of the spatial loading positions of FeCoPi and OVs with the photogenerated charge distribution of Bi_(4)NbO_(8)Cl and corresponding reaction mechanisms of substrate,the FeCoPi and OVs on the(001)and(010)crystal planes of Bi_(4)NbO_(8)Cl photocatalyst provided surface active site for water oxidation reaction and electron shuttle reaction(Fe^(3+)/Fe^(2+)),respectively.Under visible light irradiation,the evolution O_(2)rate of FeCoPi/Bi_(4)NbO_(8)Cl OVs was 16.8μmol h^(-1),as 32.9 times as Bi_(4)NbO_(8)Cl.Furthermore,a hydrogen evolution co-catalyst PtRu@Cr_(2)O_(3)was prepared by sequential photodeposition method.Due to the introduction of Ru,the Schottky barrier between PbTiO_(3)and Pt was effectively reduced,which promoted the transfer of photogenerated electrons to PtRu@Cr_(2)O_(3)thermodynamically,the evolution H_(2)rate on PtRu@Cr_(2)O_(3)/PbTiO_(3)increased to 664.8 times.On based of the synchronous enhancement of the water oxidation performance on FeCoPi/Bi_(4)NbO_(8)Cl-OVs and water reduction performance on PtRu@Cr_(2)O_(3)/PbTiO_(3),a novel Z-Scheme photocatalytic overall water splitting system(FeCoPi/Bi_(4)NbO_(8)Cl-OVs)mediated by Fe^(3+)/Fe^(2+)had successfully constructed.Under visible light irradiation,the evolution rates of H_(2)and O_(2)were 2.5 and 1.3μmol h^(-1),respectively.This work can provide some reference for the design of active site and the controllable synthesis of OVs spatial position.On the other hand,the hydrogen evolution co catalyst(PtRu@Cr_(2)O_(3))and the co catalyst FeCoPi for oxygen evolution contributed to the construction of an overall water splitting system.展开更多
The effect of nanosecond pulsed dielectric barrier discharge(NS-DBD) plasma flow separation control is closely related to the actuation frequency,because it involves the interaction between plasma-induced vortexes and...The effect of nanosecond pulsed dielectric barrier discharge(NS-DBD) plasma flow separation control is closely related to the actuation frequency,because it involves the interaction between plasma-induced vortexes and separated flow.In order to study the mechanism of NS-DBD plasma flow separation control over a swept wing,especially the influence of the actuation frequency,at first,experimental studies of the actuation frequencies at 100 Hz are conducted to validate the numerical simulation method.Then,numerical studies of different actuation frequencies which are 50 Hz,100 Hz,160 Hz,200 Hz,500 Hz,and 1000 Hz,respectively are conducted.The interaction between the plasma-induced vortexes and the separated flow is analyzed.Results show that there is a range of the actuation frequency which includes the frequency(160 Hz) calculated by the average aerodynamic chord length to make the control effect good,but when the actuation frequencies are too low(50 Hz) or too high(1000 Hz),the control effect will get worse.The former is because plasmainduced vortexes disappear in a period within an actuation cycle;the latter is because plasma-induced vortexes cannot develop completely,resulting in a weak vortex intensity.展开更多
In this paper we shall offer a separation axiom for frames inspired by the Hausdorff separation axiom for topological spaces. We call it separated condition. This is a condition on topology OX equivalent to the ...In this paper we shall offer a separation axiom for frames inspired by the Hausdorff separation axiom for topological spaces. We call it separated condition. This is a condition on topology OX equivalent to the T O space X being Hausdorff. The class of separated frames includes that of strong Hausdorff frames and that of S frames. We shall show that the class of separated frames is a class closed under the formation of coproducts and subspaces, and the space Fil( L ) is Hausdorff for any separated frame L . Therefore there is a contravariant adjunction between the category TOP 2 of Hausdorff topological spaces and the category FRAM 2 of separated frames.展开更多
In seismic exploration, it is common practice to separate the P-wavefield from the S-wavefield by the elastic wavefield decomposition technique, for imaging purposes. However, it is sometimes difficult to achieve this...In seismic exploration, it is common practice to separate the P-wavefield from the S-wavefield by the elastic wavefield decomposition technique, for imaging purposes. However, it is sometimes difficult to achieve this, especially when the velocity field is complex. A useful approach in multi-component analysis and modeling is to directly solve the elastic wave equations for the pure P- or S-wavefields, referred as the separate elastic wave equa- tions. In this study, we compare two kinds of such wave equations: the first-order (velocity-stress) and the second- order (displacement-stress) separate elastic wave equa- tions, with the first-order (velocity-stress) and the second- order (displacement-stress) full (or mixed) elastic wave equations using a high-order staggered grid finite-differ- ence method. Comparisons are given of wavefield snap- shots, common-source gather seismic sections, and individual synthetic seismogram. The simulation tests show that equivalent results can be obtained, regardless of whether the first-order or second-order separate elastic wave equations are used for obtaining the pure P- or S-wavefield. The stacked pure P- and S-wavefields are equal to the mixed wave fields calculated using the corre- sponding first-order or second-order full elastic wave equations. These mixed equations are computationallyslightly less expensive than solving the separate equations. The attraction of the separate equations is that they achieve separated P- and S-wavefields which can be used to test the efficacy of wave decomposition procedures in multi-com- ponent processing. The second-order separate elastic wave equations are a good choice because they offer information on the pure P-wave or S-wave displacements.展开更多
Numerical studies of the flow past a circular cylinder at Reynolds number 1.4 × 105 and NACA0021 airfoil at the angle of attack 60° have been carried out by scale-adaptive simulation (SAS) and detached edd...Numerical studies of the flow past a circular cylinder at Reynolds number 1.4 × 105 and NACA0021 airfoil at the angle of attack 60° have been carried out by scale-adaptive simulation (SAS) and detached eddy simu- lation (DES), in comparison with the existing experimental data. The new version of the model developed by Egorov and Menter is assessed, and advantages and disadvantages of the SAS simulation are analyzed in detail to provide guidance for industrial application in the future. Moreover, the mechanism of the scale-adaptive characteristics in separated regions is discussed, which is obscure in previous analyses. It is con- cluded that: the mean flow properties satisfactorily agree with the experimental results for the SAS simulation, although the prediction of the second order turbulent statistics in the near wake region is just reasonable. The SAS model can produce a larger magnitude of the turbulent kinetic energy in the recir- culation bubble, and, consequently, a smaller recirculation region and a more rapid recovery of the mean velocity out- side the recirculation region than the DES approach with the same grid resolution. The vortex shedding is slightly less irregular with the SAS model than with the DES approach, probably due to the higher dissipation of the SAS simulation under the condition of the coarse mesh.展开更多
By introducing a more general auxiliary ordinary differential equation (ODE), a modified variable separated ODE method is developed for solving the mKdV-sinh-Gordon equation. As a result, many explicit and exact sol...By introducing a more general auxiliary ordinary differential equation (ODE), a modified variable separated ODE method is developed for solving the mKdV-sinh-Gordon equation. As a result, many explicit and exact solutions including some new formal solutions are successfully picked up for the mKdV-sinh-Gordon equation by this approach.展开更多
Acryloyl terminated Poly (ethyleneoxide)macromonomers (PEO-A) with different PEO chain lengths have been prepared by deactivation of PEO alkoxide with acryloyl chloride. A new kind of amphiphilic polystyrene-g-poly (e...Acryloyl terminated Poly (ethyleneoxide)macromonomers (PEO-A) with different PEO chain lengths have been prepared by deactivation of PEO alkoxide with acryloyl chloride. A new kind of amphiphilic polystyrene-g-poly (ethylene oxide)graft copolymer containing both microphase separated and PEO side chain structures has been synthesized from radical copolymerization of PEO-A macromonomer with styrene. After careful purification by a newly-developed method called 'selective dissolution', the well-defined structure of the purified copolymers was confirmed by IR, ~1H-NMR and GPC. Various experimental parameters controlling the copolymerization were studied in detail. The results indicated that the feed ratio of styrene to macromonomer(S/M) was the most important determining factor for the composition of the copolymers. A detailed 'comb- model' was proposed to describe the molecular structure of the graft copolymers. Finally, this amphiphilic graft copolymers may readily form microphase separated structures as clearly indicated by transmission electron microscopy.展开更多
The state estimation of a maneuvering target,of which the trajectory shape is independent on dynamic characteristics,is studied.The conventional motion models in Cartesian coordinates imply that the trajectory of a ta...The state estimation of a maneuvering target,of which the trajectory shape is independent on dynamic characteristics,is studied.The conventional motion models in Cartesian coordinates imply that the trajectory of a target is completely determined by its dynamic characteristics.However,this is not true in the applications of road-target,sea-route-target or flight route-target tracking,where target trajectory shape is uncoupled with target velocity properties.In this paper,a new estimation algorithm based on separate modeling of target trajectory shape and dynamic characteristics is proposed.The trajectory of a target over a sliding window is described by a linear function of the arc length.To determine the unknown target trajectory,an augmented system is derived by denoting the unknown coefficients of the function as states in mileage coordinates.At every estimation cycle except the first one,the interaction(mixing)stage of the proposed algorithm starts from the latest estimated base state and a recalculated parameter vector,which is determined by the least squares(LS).Numerical experiments are conducted to assess the performance of the proposed algorithm.Simulation results show that the proposed algorithm can achieve better performance than the conventional coupled model-based algorithms in the presence of target maneuvers.展开更多
Separate type heat pipe heat exchangers are often used for large-scale heat exchanging. The arrangement of such a heat exchanger conveniently allows heat input to and output from the heat exchanger at remote locations...Separate type heat pipe heat exchangers are often used for large-scale heat exchanging. The arrangement of such a heat exchanger conveniently allows heat input to and output from the heat exchanger at remote locations. The traditional method of designing an ordinary HPHE (heat pipe heat exchanger) is commonly applied in the separate type exchanger design, but the calculations have to be carried out separately, which makes it very complicated. In this work, the ε-NTU (effectiveness-Number of Transfer Units) method was applied for optimization analysis of single- or multi-level separate type heat pipe heat exchangers. An optimizing formula for single-level separate type heat pipe heat exchangers was obtained. The optimizing principles of effec- tiveness-NTU and heat transfer rate by the equal distribution method for multi-level separate type heat pipe heat exchanger are presented. The design of separate type heat pipe heat exchangers by the optimizing method is more convenient and faster than by the traditional method.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.12174149)。
文摘Metal-free organic emitters,characterized by their thermally activated delayed fluorescence(TADF)properties,offer considerable promise for the creation of highly efficient organic light-emitting diodes(OLEDs).Recently,Shao et al.presented a novel excited state intramolecular proton transfer(ESIPT)system BrA-HBI,demonstrating an emission quantum yield of up to 50%[Adv.Funct.Mater.32,2201256(2022)].However,many open issues cannot be answered solely by experimental means only and require detailed theoretical investigations.For instance,what causes the activation of TADF from the Keto*tautomer and leads to fluorescence quenching in the Enol^(*)form?Herein,we provide a theoretical investigation on the TADF mechanism of the BrA-HBI molecule by optimally tuned range-separated functionals.Our findings reveal that ESIPT occurs in the BrA-HBI molecule.Moreover,we have disclosed the reason for the fluorescence quenching of the Enol^(*)form and determined that the T_(2)state plays a dominant role in the TADF phenomenon.In addition,double hybrid density functionals method was utilized to verify the reliability of optimally tuned range separation functionals on the calculation of the TADF mechanism in BrA-HBI.These findings not only provide a theoretical reference for development of highly efficient organic light-emitting diodes,but also demonstrate the effectiveness of the optimally tuned range-separated functionals in predicting the luminescence properties of TADF molecules.
基金Supported by the Major Science and Technology Project of CNPC(2023ZZ19-01).
文摘Based on the waterflooding development in carbonate reservoirs in the Middle East,in order to solve the problem of the poor development effects caused by commingled injection and production,taking the thick bioclastic limestone reservoirs of Cretaceous in Iran-Iraq as an example,this paper proposes a balanced waterflooding development technology for thick and complex carbonate reservoirs.This technology includes the fine division of development units by concealed baffles and barriers,the combination of multi well type and multi well pattern,and the construction of balanced water injection and recovery system.Thick carbonate reservoirs in Iran-Iraq are characterized by extremely vertical heterogeneity,development of multi-genesis ultra-high permeability zones,and highly concealed baffles and barriers.Based on the technologies of identification,characterization,and sealing evaluation for concealed baffles and barriers,the balanced waterflooding development technology is proposed,and three types of balanced waterflooding development modes/techniques are formed,namely,conventional stratigraphic framework,fine stratigraphic framework,and deepened stratigraphic framework.Numerical simulations show that this technology is able to realize a fine and efficient waterflooding development to recover,in a balanced manner,the reserves of thick and complex carbonate reservoirs in Iran and Iraq.The proposed technology provides a reference for the development optimization of similar reservoirs.
基金2023 Young and Middle-aged University Teachers Basic Scientific Research Ability Improvement Project in Guangxi(2023KY0299)High-level Key Discipline Construction Project of Traditional Chinese Medicine of National Administration of Traditional Chinese Medicine(zyyzdxk-2023165)+3 种基金Talent Training Project of Guangxi International Zhuang Medicine Hospital—"Young Seedling Project"(2022001)Guangxi Traditional Chinese Medicine Multidisciplinary and Interdisciplinary Innovation Team Project(GZKJ2309)High-level Talent Cultivation Innovation Team Funding Project of Guangxi University of Chinese Medicine(2022A008)2023 Three-Year Action Plan Project for High-Level Talent Team Construction of Guangxi International Zhuang Medicine Hospital(GZCX20231203,GZCX20231202).
文摘[Objectives]To investigate the effect and mechanism of Dachengqi Decoction and separated decoction on incomplete intestinal obstruction in rats.[Methods]80 healthy SD rats were selected to establish incomplete intestinal obstruction model by silk ligation.The dosage was 20 mL/kg for 3 d,and the damage index of ileocecal mucosa was analyzed;the morphology of ileocecal mucosa was observed by HE staining;the serum levels of IL-1α,IL-1β,IL-6,IL-18,Ach,NO,ET,IL-1,TNF-αand ultra-micro Na+-K+-ATPase were detected by ELISA.[Results]Compared with the model group,the mucosal damage index of Dachengqi Decoction and each separated decoction group decreased significantly(P<0.05);compared with the normal group and sham operation group,the serum level of IL-1,IL-6,TNF-αand other factors in the model group increased significantly(P<0.05);compared with the model group,the serum IL-1,IL-6 and TNF-αsecretion levels of rats in Dachengqi Decoction group and separated decoction group decreased(P<0.01).[Conclusions]Dachengqi Decoction and each separated decoction can effectively improve intestinal tissue pathological damage in the incomplete intestinal obstruction model rats,and reduce the inflammatory reaction in the rat body.
文摘An investigation of the decoupled thermal–hydraulic analysis of a separated heat pipe spent fuel pool passive cooling system(SFS)is essential for practical engineering applications.Based on the principles of thermal and mass balance,this study decoupled the heat transfer processes in the SFS.In accordance with the decoupling conditions,we modeled the spent fuel pool of the CAP1400 pressurized water reactor in Weihai and used computational fluid dynamics to explore the heat dissipation capacity of the SFS under different air temperatures and wind speeds.The results show that the air-cooled separated heat pipe radiator achieved optimal performance at an air temperature of 10℃ or wind speed of 8 m/s.Fitted equations for the equivalent thermal conductivity of the separated heat pipes with the wind speed and air temperature we obtained according to the thermal resistance network model.This study is instructive for the actual operation of an SFS.
基金Supported by the National Natural Science Foundation Science Center Project/Basic Science Center Project(72088101)PetroChina Scientific Research and Technology Development Project(2020B-4119,2021ZG12).
文摘This article outlines the development of downhole monitoring and data transmission technology for separated zone water injection in China.According to the development stages,the principles,operation processes,adaptability and application status of traditional downhole data acquisition method,cable communications and testing technology,cable-controlled downhole parameter real-time monitoring communication method and downhole wireless communication technology are introduced in detail.Problems and challenges of existing technologies in downhole monitoring and data transmission technology are pointed out.According to the production requirement,the future development direction of the downhole monitoring and data transmission technology for separated zone water injection is proposed.For the large number of wells adopting cable measuring and adjustment technology,the key is to realize the digitalization of downhole plug.For the key monitoring wells,cable-controlled communication technology needs to be improved,and downhole monitoring and data transmission technology based on composite coiled tubing needs to be developed to make the operation more convenient and reliable.For large-scale application in oil fields,downhole wireless communication technology should be developed to realize automation of measurement and adjustment.In line with ground mobile communication network,a digital communication network covering the control center,water distribution station and oil reservoir should be built quickly to provide technical support for the digitization of reservoir development.
文摘A recent article in the Opto-Electronic Advances(OEA)journal from Prof.Qian Chen and Prof.Chao Zuo’s group introduced a new and efficient 3D imaging system that captures high-speed images using deep learning-enabled fringe projection profilometry(FPP).In this News&Views article,we explore potential avenues for future advancements,including expanding the measurement range through an extended number-theoretical approach,enhancing quality through the incorporation of horizontal fringes,and integrating data from other modalities to broaden the system's applications.
文摘BACKGROUND It remains unclear whether laparoscopic multisegmental resection and ana-stomosis(LMRA)is safe and advantageous over traditional open multisegmental resection and anastomosis(OMRA)for treating synchronous colorectal cancer(SCRC)located in separate segments.AIM To compare the short-term efficacy and long-term prognosis of OMRA as well as LMRA for SCRC located in separate segments.METHODS Patients with SCRC who underwent surgery between January 2010 and December 2021 at the Cancer Hospital,Chinese Academy of Medical Sciences and the Peking University First Hospital were retrospectively recruited.In accordance with the RESULTS LMRA patients showed markedly less intraoperative blood loss than OMRA patients(100 vs 200 mL,P=0.006).Compared to OMRA patients,LMRA patients exhibited markedly shorter postoperative first exhaust time(2 vs 3 d,P=0.001),postoperative first fluid intake time(3 vs 4 d,P=0.012),and postoperative hospital stay(9 vs 12 d,P=0.002).The incidence of total postoperative complications(Clavien-Dindo grade:≥II)was 2.9%and 17.1%(P=0.025)in the LMRA and OMRA groups,respectively,while the incidence of anastomotic leakage was 2.9%and 7.3%(P=0.558)in the LMRA and OMRA groups,respectively.Furthermore,the LMRA group had a higher mean number of lymph nodes dissected than the OMRA group(45.2 vs 37.3,P=0.020).The 5-year overall survival(OS)and disease-free survival(DFS)rates in OMRA patients were 82.9%and 78.3%,respectively,while these rates in LMRA patients were 78.2%and 72.8%,respectively.Multivariate prognostic analysis revealed that N stage[OS:HR hazard ratio(HR)=10.161,P=0.026;DFS:HR=13.017,P=0.013],but not the surgical method(LMRA/OMRA)(OS:HR=0.834,P=0.749;DFS:HR=0.812,P=0.712),was the independent influencing factor in the OS and DFS of patients with SCRC.CONCLUSION LMRA is safe and feasible for patients with SCRC located in separate segments.Compared to OMRA,the LMRA approach has more advantages related to short-term efficacy.
文摘In this paper, we introduce a novel scheme for the separate training of deep learning-based autoencoders used for Channel State Information (CSI) feedback. Our distinct training approach caters to multiple users and base stations, enabling independent and individualized local training. This ensures the more secure processing of data and algorithms, different from the commonly adopted joint training method. To maintain comparable performance with joint training, we present two distinct training methods: separate training decoder and separate training encoder. It’s noteworthy that conducting separate training for the encoder can pose additional challenges, due to its responsibility in acquiring a compressed representation of underlying data features. This complexity makes accommodating multiple pre-trained decoders for just one encoder a demanding task. To overcome this, we design an adaptation layer architecture that effectively minimizes performance losses. Moreover, the flexible training strategy empowers users and base stations to seamlessly incorporate distinct encoder and decoder structures into the system, significantly amplifying the system’s scalability. .
基金supported by National Natural Science Foundation of China(22369022)Technology Innovation Leading Program of Shaanxi(2022QFY07-03)。
文摘The efficiency of photocatalytic overall water splitting was mainly limited by the slow reaction kinetics of water oxidation.How to design effective surface active site to overcome the slow water oxidation reaction was a major challenge.Here,we propose a strategy to accelerate surface water oxidation through the fabrication spatially separated double active sites.FeCoPi/Bi_(4)NbO_(8)Cl-OVs photocatalyst with spatially separated double active site was prepared by hydrogen reduction photoanode deposition method.Due to the high matching of the spatial loading positions of FeCoPi and OVs with the photogenerated charge distribution of Bi_(4)NbO_(8)Cl and corresponding reaction mechanisms of substrate,the FeCoPi and OVs on the(001)and(010)crystal planes of Bi_(4)NbO_(8)Cl photocatalyst provided surface active site for water oxidation reaction and electron shuttle reaction(Fe^(3+)/Fe^(2+)),respectively.Under visible light irradiation,the evolution O_(2)rate of FeCoPi/Bi_(4)NbO_(8)Cl OVs was 16.8μmol h^(-1),as 32.9 times as Bi_(4)NbO_(8)Cl.Furthermore,a hydrogen evolution co-catalyst PtRu@Cr_(2)O_(3)was prepared by sequential photodeposition method.Due to the introduction of Ru,the Schottky barrier between PbTiO_(3)and Pt was effectively reduced,which promoted the transfer of photogenerated electrons to PtRu@Cr_(2)O_(3)thermodynamically,the evolution H_(2)rate on PtRu@Cr_(2)O_(3)/PbTiO_(3)increased to 664.8 times.On based of the synchronous enhancement of the water oxidation performance on FeCoPi/Bi_(4)NbO_(8)Cl-OVs and water reduction performance on PtRu@Cr_(2)O_(3)/PbTiO_(3),a novel Z-Scheme photocatalytic overall water splitting system(FeCoPi/Bi_(4)NbO_(8)Cl-OVs)mediated by Fe^(3+)/Fe^(2+)had successfully constructed.Under visible light irradiation,the evolution rates of H_(2)and O_(2)were 2.5 and 1.3μmol h^(-1),respectively.This work can provide some reference for the design of active site and the controllable synthesis of OVs spatial position.On the other hand,the hydrogen evolution co catalyst(PtRu@Cr_(2)O_(3))and the co catalyst FeCoPi for oxygen evolution contributed to the construction of an overall water splitting system.
基金National Science and Technology Major Project (No.J2019-Ⅱ-0014-0035)Academician Workstation Foundation of the Green Aerotechnics Research Institute of Chonging Jiaotong University (No. GATRI2020C06003)。
文摘The effect of nanosecond pulsed dielectric barrier discharge(NS-DBD) plasma flow separation control is closely related to the actuation frequency,because it involves the interaction between plasma-induced vortexes and separated flow.In order to study the mechanism of NS-DBD plasma flow separation control over a swept wing,especially the influence of the actuation frequency,at first,experimental studies of the actuation frequencies at 100 Hz are conducted to validate the numerical simulation method.Then,numerical studies of different actuation frequencies which are 50 Hz,100 Hz,160 Hz,200 Hz,500 Hz,and 1000 Hz,respectively are conducted.The interaction between the plasma-induced vortexes and the separated flow is analyzed.Results show that there is a range of the actuation frequency which includes the frequency(160 Hz) calculated by the average aerodynamic chord length to make the control effect good,but when the actuation frequencies are too low(50 Hz) or too high(1000 Hz),the control effect will get worse.The former is because plasmainduced vortexes disappear in a period within an actuation cycle;the latter is because plasma-induced vortexes cannot develop completely,resulting in a weak vortex intensity.
文摘In this paper we shall offer a separation axiom for frames inspired by the Hausdorff separation axiom for topological spaces. We call it separated condition. This is a condition on topology OX equivalent to the T O space X being Hausdorff. The class of separated frames includes that of strong Hausdorff frames and that of S frames. We shall show that the class of separated frames is a class closed under the formation of coproducts and subspaces, and the space Fil( L ) is Hausdorff for any separated frame L . Therefore there is a contravariant adjunction between the category TOP 2 of Hausdorff topological spaces and the category FRAM 2 of separated frames.
基金partially supported by China National Major Science and Technology Project (Subproject No:2011ZX05024-001-03)
文摘In seismic exploration, it is common practice to separate the P-wavefield from the S-wavefield by the elastic wavefield decomposition technique, for imaging purposes. However, it is sometimes difficult to achieve this, especially when the velocity field is complex. A useful approach in multi-component analysis and modeling is to directly solve the elastic wave equations for the pure P- or S-wavefields, referred as the separate elastic wave equa- tions. In this study, we compare two kinds of such wave equations: the first-order (velocity-stress) and the second- order (displacement-stress) separate elastic wave equa- tions, with the first-order (velocity-stress) and the second- order (displacement-stress) full (or mixed) elastic wave equations using a high-order staggered grid finite-differ- ence method. Comparisons are given of wavefield snap- shots, common-source gather seismic sections, and individual synthetic seismogram. The simulation tests show that equivalent results can be obtained, regardless of whether the first-order or second-order separate elastic wave equations are used for obtaining the pure P- or S-wavefield. The stacked pure P- and S-wavefields are equal to the mixed wave fields calculated using the corre- sponding first-order or second-order full elastic wave equations. These mixed equations are computationallyslightly less expensive than solving the separate equations. The attraction of the separate equations is that they achieve separated P- and S-wavefields which can be used to test the efficacy of wave decomposition procedures in multi-com- ponent processing. The second-order separate elastic wave equations are a good choice because they offer information on the pure P-wave or S-wave displacements.
基金the National Basic Research Program of China ("973" Project) (Grant No. 2009CB724104)
文摘Numerical studies of the flow past a circular cylinder at Reynolds number 1.4 × 105 and NACA0021 airfoil at the angle of attack 60° have been carried out by scale-adaptive simulation (SAS) and detached eddy simu- lation (DES), in comparison with the existing experimental data. The new version of the model developed by Egorov and Menter is assessed, and advantages and disadvantages of the SAS simulation are analyzed in detail to provide guidance for industrial application in the future. Moreover, the mechanism of the scale-adaptive characteristics in separated regions is discussed, which is obscure in previous analyses. It is con- cluded that: the mean flow properties satisfactorily agree with the experimental results for the SAS simulation, although the prediction of the second order turbulent statistics in the near wake region is just reasonable. The SAS model can produce a larger magnitude of the turbulent kinetic energy in the recir- culation bubble, and, consequently, a smaller recirculation region and a more rapid recovery of the mean velocity out- side the recirculation region than the DES approach with the same grid resolution. The vortex shedding is slightly less irregular with the SAS model than with the DES approach, probably due to the higher dissipation of the SAS simulation under the condition of the coarse mesh.
基金Project supported by the National Natural Science Foundation of China (Grant No 10672053)
文摘By introducing a more general auxiliary ordinary differential equation (ODE), a modified variable separated ODE method is developed for solving the mKdV-sinh-Gordon equation. As a result, many explicit and exact solutions including some new formal solutions are successfully picked up for the mKdV-sinh-Gordon equation by this approach.
基金Supported by the National Natural Science Foundation of China and the State Education Committee of China
文摘Acryloyl terminated Poly (ethyleneoxide)macromonomers (PEO-A) with different PEO chain lengths have been prepared by deactivation of PEO alkoxide with acryloyl chloride. A new kind of amphiphilic polystyrene-g-poly (ethylene oxide)graft copolymer containing both microphase separated and PEO side chain structures has been synthesized from radical copolymerization of PEO-A macromonomer with styrene. After careful purification by a newly-developed method called 'selective dissolution', the well-defined structure of the purified copolymers was confirmed by IR, ~1H-NMR and GPC. Various experimental parameters controlling the copolymerization were studied in detail. The results indicated that the feed ratio of styrene to macromonomer(S/M) was the most important determining factor for the composition of the copolymers. A detailed 'comb- model' was proposed to describe the molecular structure of the graft copolymers. Finally, this amphiphilic graft copolymers may readily form microphase separated structures as clearly indicated by transmission electron microscopy.
基金supported by the National Natural Science Foundation of China(61671181).
文摘The state estimation of a maneuvering target,of which the trajectory shape is independent on dynamic characteristics,is studied.The conventional motion models in Cartesian coordinates imply that the trajectory of a target is completely determined by its dynamic characteristics.However,this is not true in the applications of road-target,sea-route-target or flight route-target tracking,where target trajectory shape is uncoupled with target velocity properties.In this paper,a new estimation algorithm based on separate modeling of target trajectory shape and dynamic characteristics is proposed.The trajectory of a target over a sliding window is described by a linear function of the arc length.To determine the unknown target trajectory,an augmented system is derived by denoting the unknown coefficients of the function as states in mileage coordinates.At every estimation cycle except the first one,the interaction(mixing)stage of the proposed algorithm starts from the latest estimated base state and a recalculated parameter vector,which is determined by the least squares(LS).Numerical experiments are conducted to assess the performance of the proposed algorithm.Simulation results show that the proposed algorithm can achieve better performance than the conventional coupled model-based algorithms in the presence of target maneuvers.
文摘Separate type heat pipe heat exchangers are often used for large-scale heat exchanging. The arrangement of such a heat exchanger conveniently allows heat input to and output from the heat exchanger at remote locations. The traditional method of designing an ordinary HPHE (heat pipe heat exchanger) is commonly applied in the separate type exchanger design, but the calculations have to be carried out separately, which makes it very complicated. In this work, the ε-NTU (effectiveness-Number of Transfer Units) method was applied for optimization analysis of single- or multi-level separate type heat pipe heat exchangers. An optimizing formula for single-level separate type heat pipe heat exchangers was obtained. The optimizing principles of effec- tiveness-NTU and heat transfer rate by the equal distribution method for multi-level separate type heat pipe heat exchanger are presented. The design of separate type heat pipe heat exchangers by the optimizing method is more convenient and faster than by the traditional method.