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Accelerating Hartree-Fock Self-consistent Field Calculation on C86/DCU Heterogenous Computing Platform
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作者 Ji Qi Huimin Zhang +1 位作者 Dezun Shan Minghui Yang 《Chinese Journal of Chemical Physics》 2025年第1期81-94,I0056,共15页
In this study,we investigate the ef-ficacy of a hybrid parallel algo-rithm aiming at enhancing the speed of evaluation of two-electron repulsion integrals(ERI)and Fock matrix generation on the Hygon C86/DCU(deep compu... In this study,we investigate the ef-ficacy of a hybrid parallel algo-rithm aiming at enhancing the speed of evaluation of two-electron repulsion integrals(ERI)and Fock matrix generation on the Hygon C86/DCU(deep computing unit)heterogeneous computing platform.Multiple hybrid parallel schemes are assessed using a range of model systems,including those with up to 1200 atoms and 10000 basis func-tions.The findings of our research reveal that,during Hartree-Fock(HF)calculations,a single DCU ex-hibits 33.6 speedups over 32 C86 CPU cores.Compared with the efficiency of Wuhan Electronic Structure Package on Intel X86 and NVIDIA A100 computing platform,the Hygon platform exhibits good cost-effective-ness,showing great potential in quantum chemistry calculation and other high-performance scientific computations. 展开更多
关键词 Quantum chemistry Self-consistent field HARTREE-FOCK Electron repulsion inte-grals heterogenous parallel computing C86/deep computing unit
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A weak formulation of heterogenous viscoacoustic wave propagation in infinite domain
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作者 Xie Zhinan Zheng Yonglu +4 位作者 Paul Cristini Alexis Bottero Shan Zhendong Lu Jianqi Zhang Xubin 《Earthquake Engineering and Engineering Vibration》 2025年第1期31-51,共21页
The accurate simulation of wave propagation in real media requires properly taking the attenuation into account,which leads to wave dissipation together with its causal companion,wave dispersion.In this study,to obtai... The accurate simulation of wave propagation in real media requires properly taking the attenuation into account,which leads to wave dissipation together with its causal companion,wave dispersion.In this study,to obtain a weak formulation of heterogenous viscoacoustic wave propagation in an infinite domain,the viscoacoustic medium is first characterized by its frequency-dependent complex bulk compliance instead of the classically used complex bulk modulus.Then,a mechanical model using serially connected standard linear solids(SSLS)is built to obtain the rational approximation of the complex bulk compliance whose parameters are calculated via an adapted nonlinear optimization method.Utilizing the obtained bulk compliance-based constitutive relation,a novel second-order viscoacoustic wave equation in the frequency domain is derived,of which the weak formulation can be physically explained as the virtual work equation and can thus be discretized using a continuous spectral element method in space.Additionally,a new method is introduced to address the convolution terms involved in the inverse Fourier transform,whose accurate time integration can then be achieved using an explicit time scheme,which avoids the transient growth that exists in the classical method.The resulting full time-space decoupling scheme can handle wave propagation in arbitrary heterogeneous media.Moreover,to treat the wave propagation in an infinite domain,a perfectly matched layer in weak formulation is derived for the truncation of the infinite domain via complex coordinate stretching of the virtual work equation.With only minor modification,the resulting perfectly matched layer can be implemented using the same time scheme as for the wave equation inside the truncated domain.The accuracy,numerical stability,and versatility of the new proposed scheme are demonstrated with numerical examples. 展开更多
关键词 viscoacoustic wave standard linear solid complex bulk compliance heterogenous media perfectly matched layer Legendre spectral element method
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A candidate protective factor in amyotrophic lateral sclerosis:heterogenous nuclear ribonucleoprotein G 被引量:2
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作者 Fang Yang Wen-Zhi Chen +2 位作者 Shi-Shi Jiang Xiao-Hua Wang Ren-Shi Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第7期1527-1534,共8页
Heterogenous nuclear ribonucleoprotein G is down-regulated in the spinal cord of the Tg(SOD1*G93A)1Gur(TG)amyotrophic lateral sclerosis mouse model.However,most studies have only examined heterogenous nuclear ribonucl... Heterogenous nuclear ribonucleoprotein G is down-regulated in the spinal cord of the Tg(SOD1*G93A)1Gur(TG)amyotrophic lateral sclerosis mouse model.However,most studies have only examined heterogenous nuclear ribonucleoprotein G expression in the amyotrophic lateral sclerosis model and heterogenous nuclear ribonucleoprotein G effects in amyotrophic lateral sclerosis pathogenesis such as in apoptosis are unknown.In this study,we studied the potential mechanism of heterogenous nuclear ribonucleoprotein G in neuronal death in the spinal cord of TG and wild-type mice and examined the mechanism by which heterogenous nuclear ribonucleoprotein G induces apoptosis.Heterogenous nuclear ribonucleoprotein G in spinal cord was analyzed using immunohistochemistry and western blotting,and cell proliferation and proteins(TAR DNA binding protein 43,superoxide dismutase 1,and Bax)were detected by the Cell Counting Kit-8 and western blot analysis in heterogenous nuclear ribonucleoprotein G siRNA-transfected PC12 cells.We analyzed heterogenous nuclear ribonucleoprotein G distribution in spinal cord in the amyotrophic lateral sclerosis model at various time points and the expressions of apoptosis and proliferation-related proteins.Heterogenous nuclear ribonucleoprotein G was mainly localized in neurons.Amyotrophic lateral sclerosis mice were examined at three stages:preonset(60-70 days),onset(90-100 days)and progression(120-130 days).The number of heterogenous nuclear ribonucleoprotein G-positive cells was significantly higher in the anterior horn of the lumbar spinal cord segment of TG mice at the preonset stage than that of control group but lower than that of the control group at the onset stage.The number of heterogenous nuclear ribonucleoprotein G-positive cells in both central canal and surrounding gray matter of the whole spinal cord of TG mice at the onset stage was significantly lower than that in the control group,whereas that of the lumbar spinal cord segment of TG mice was significantly higher than that in the control group at preonset stage and significantly lower than that in the control group at the progression stage.The numbers of heterogenous nuclear ribonucleoprotein G-positive cells in the posterior horn of cervical and thoracic segments of TG mice at preonset and progression stages were significantly lower than those in the control group.The expression of heterogenous nuclear ribonucleoprotein G in the cervical spinal cord segment of TG mice was significantly higher than that in the control group at the preonset stage but significantly lower at the progression stage.The expression of heterogenous nuclear ribonucleoprotein G in the thoracic spinal cord segment of TG mice was significantly increased at the preonset stage,significantly decreased at the onset stage,and significantly increased at the progression stage compared with the control group.heterogenous nuclear ribonucleoprotein G expression in the lumbar spinal cord segment of TG mice was significantly lower than that of the control group at the progression stage.After heterogenous nuclear ribonucleoprotein G gene silencing,PC12 cell survival was lower than that of control cells.Both TAR DNA binding protein 43 and Bax expressions were significantly increased in heterogenous nuclear ribonucleoprotein G-silenced cells compared with control cells.Our study suggests that abnormal distribution and expression of heterogenous nuclear ribonucleoprotein G might play a protective effect in amyotrophic lateral sclerosis development via preventing neuronal death by reducing abnormal TAR DNA binding protein 43 generation in the spinal cord. 展开更多
关键词 amyotrophic lateral sclerosis Bax heterogenous nuclear ribonucleoprotein G heterogenous nuclear ribonucleoprotein G-siRNA neuron death superoxide dismutase 1 TAR DNA binding protein 43 TG(SOD1*G93A)1Gur mice
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Extrahepatic bile duct reconstruction in pigs with heterogenous animal-derived artificial bile ducts:A preliminary experience 被引量:2
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作者 Hao Shang Jian-Ping Zeng +7 位作者 Si-Yuan Wang Ying Xiao Jiang-Hui Yang Shao-Qing Yu Xiang-Chen Liu Nan Jiang Xia-Li Shi Shuo Jin 《World Journal of Gastroenterology》 SCIE CAS 2020年第46期7312-7324,共13页
BACKGROUND Extrahepatic biliary duct injury(BDI)remains a complicated issue for surgeons.Although several approaches have been explored to address this problem,the high incidence of complications affects postoperative... BACKGROUND Extrahepatic biliary duct injury(BDI)remains a complicated issue for surgeons.Although several approaches have been explored to address this problem,the high incidence of complications affects postoperative recovery.As a nonimmunogenic scaffold,an animal-derived artificial bile duct(ada-BD)could replace the defect,providing good physiological conditions for the regeneration of autologous bile duct structures without changing the original anatomical and physiologic conditions.AIM To evaluate the long-term feasibility of a novel heterogenous ada-BD for treating extrahepatic BDI in pigs.METHODS Eight pigs were randomly divided into two groups in the study.The animal injury model was developed with an approximately 2 cm segmental defect of various parts of the common bile duct(CBD)for all pigs.A 2 cm long novel heterogenous animal-derived bile duct was used to repair this segmental defect(group A,ada-BD-to-duodenum anastomosis to repair the distal CBD defect;group B,ada-BD-to-CBD anastomosis to repair the intermedial CBD defect).The endpoint for observation was 6 mo(group A)and 12 mo(group B)after the operation.Liver function was regularly tested.Animals were euthanized at the above endpoints.Histological analysis was carried out to assess the efficacy of the repair.RESULTS The median operative time was 2.45 h(2-3 h),with a median anastomosis time of 60.5 min(55-73 min).All experimental animals survived until the endpoints for observation.The liver function was almost regular.Histologic analysis indicated a marked biliary epithelial layer covering the neo-bile duct and regeneration of the submucosal connective tissue and smooth muscle without significant signs of immune rejection.In comparison,the submucosal connective tissue was more regular and thicker in group B than in group A,and there was superior integrity of the regeneration of the biliary epithelial layer.Despite the advantages of the regeneration of the bile duct smooth muscle observed in group A,the effect on the patency of the ada-BD grafts in group B was not confirmed by macroscopic assessment and cholangiography.CONCLUSION This approach appears to be feasible for repairing a CBD defect with an ada-BD.A large sample study is needed to confirm the durability and safety of these preliminary results. 展开更多
关键词 Bile duct injury Animal-derived artificial bile duct heterogenous ureteral graft Nonimmunogenic Bile duct reconstruction Common bile duct
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Application of Heterogenous Catalysis with TiO2 Photo Irradiated by Sunlight and Latter Activated Sludge System for the Reduction of Vinasse Organic Load
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作者 Juliana Sanches Carrocci Rodrigo Yuji Mori +4 位作者 Oswaldo Luiz Cobra Guimaraes Rodrigo Fernando dos Santos Salazar Marcos Fernandes de Oliveira Andre Luis de Castro Peixoto Helcio Jose Izario Filho 《Engineering(科研)》 2012年第11期746-760,共15页
Vinasse is the main residue generated during alcohol, sugar and blue rum production by fermentation process. This residue is effluent that could cause serious environmental pollution due to high organic load when is n... Vinasse is the main residue generated during alcohol, sugar and blue rum production by fermentation process. This residue is effluent that could cause serious environmental pollution due to high organic load when is not treated adequately. The aim of this work consists of evaluating the efficiency and application of heterogeneous photocatalysis with TiO2, followed by a biological treatment (activated sludge system) to reduce organic load in the referred effluent. Complete factorial designs indicated the best experimental conditions subsequent to photacatalytic and biological treatments providing a reduction of non-purgeable organic carbon (NPOC) as a variable response. After the photocatalytic process, the sample from the best experiment condition was treated by a biological process in order to verify the degradation efficiency of the effluent organic matter studied according to the hybrid system (Advanced Oxidation Process—Acti- vated Sludge System). This system, which presented more efficiency, had a photochemical treatment of 180 minutes carried out in aerated solutions, pH 9 and effluent in natura, while the biological treatment was performed at pH 8 and sludge concentration of 5 gL–1. The reduction of biochemical oxygen demand (BOD) was >80%. 展开更多
关键词 heterogenous Catalysis Activated Sludge Organic Load
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Significance of the antigenic epitopes in heterogenous nuclear ribonucleoproteins-Ⅰfor the diagnosis and prognosis of systematic sclerosis
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作者 JING XUE ZHONG QIANG YAO +2 位作者 YANG GAO MENG XUE YU LI PING ZHU 《Journal of Microbiology and Immunology》 2006年第4期300-305,共6页
To assess the presence of autoantibodies against epitopes of heterogenous nuclear ribonucleoprotein- Ⅰ (hnRNP- Ⅰ ) in systematic sclerosis (SSc) and to analyze their clinical significance, polypeptides of hnRNP-... To assess the presence of autoantibodies against epitopes of heterogenous nuclear ribonucleoprotein- Ⅰ (hnRNP- Ⅰ ) in systematic sclerosis (SSc) and to analyze their clinical significance, polypeptides of hnRNP- Ⅰ were designed by biological technical software and analyzed with both the Wonderful Biology Information System and DNA Star-Protean Analysis Software at the same time. In these ways, two polypeptides of hnRNP- Ⅰ were obtained based on their amino acid sequences, folding features, hydrophilic, curl style, dough kneading sensation and the possibility on the surface of proteins. They are named as hnRNP- Ⅰ -1 ( NVKYNNDKSRDYTRPDLPSGDSQPSLDQT, 264-292 aa) and hnRNP- Ⅰ -2 (QLP4REGQEDQGLTKDYGNSOL, 441-461 aa), simply designated as Ⅰ -1 and Ⅰ -2. The autoantibodies against hnRNPs were detected by means of ELISA using the synthetic epitopes polypeptides as antigen. It was found that the positive rate of detection for anti- Ⅰ -1 and anti- Ⅰ -2 autoantibodies were rather higher in SSc patients than that in other CTDs and the sensitivities and specificities of the testing with ELISA for anti- Ⅰ -1 and anti- Ⅰ -2 antibodies in SSc patients were 47.62%/93.43% and 38.1%/ 91.08%, without any significant difference between these two groups of testings. Also, there was no significant difference in the clinical features and laboratory findings, such as age, involvements in digestive and respiratory tracts and erythrocyte sedimentation rate etc., between the anti- Ⅰ -Ⅰ-positive and -negative groups in SSc patients. However, the hnRNP- Ⅰ -autoantibody-positive group of patients had obviously shorter duration of disease course compared with that of the autoantibody-negative group. Anti- Ⅰ -1 and anti- Ⅰ -2 autoantibodies also had no association with antinuclear antibody, anti-Sc170 and anti-centromere antibody (ACA) in SSc patients. So, it is apparent that the autoantibodies related with SSc may act through different pathways in the pathogenesis of SSc, and the hnRNP- Ⅰ autoantibody is a new type antibody occuring during the early stage of disease and appearing to have diagnostic and prognostic significances. 展开更多
关键词 heterogenous nuclear ribonucleoprotein- (hnRNP- Systemic sclerosis Epitope Enzyme-linked immonosorbent assay (ELISA)
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Role of heterogenous microstructure and deformation behavior in achieving superior strength-ductility synergy in zinc fabricated via laser powder bed fusion 被引量:5
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作者 Zhi Dong Changjun Han +7 位作者 Yanzhe Zhao Jinmiao Huang Chenrong Ling Gaoling Hu Yunhui Wang Di Wang Changhui Song Yongqiang Yang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第4期225-245,共21页
Zinc(Zn)is considered a promising biodegradable metal for implant applications due to its appropriate degradability and favorable osteogenesis properties.In this work,laser powder bed fusion(LPBF)additive manufacturin... Zinc(Zn)is considered a promising biodegradable metal for implant applications due to its appropriate degradability and favorable osteogenesis properties.In this work,laser powder bed fusion(LPBF)additive manufacturing was employed to fabricate pure Zn with a heterogeneous microstructure and exceptional strength-ductility synergy.An optimized processing window of LPBF was established for printing Zn samples with relative densities greater than 99%using a laser power range of 80∼90 W and a scanning speed of 900 mm s−1.The Zn sample printed with a power of 80 W at a speed of 900 mm s−1 exhibited a hierarchical heterogeneous microstructure consisting of millimeter-scale molten pool boundaries,micrometer-scale bimodal grains,and nanometer-scale pre-existing dislocations,due to rapid cooling rates and significant thermal gradients formed in the molten pools.The printed sample exhibited the highest ductility of∼12.1%among all reported LPBF-printed pure Zn to date with appreciable ultimate tensile strength(∼128.7 MPa).Such superior strength-ductility synergy can be attributed to the presence of multiple deformation mechanisms that are primarily governed by heterogeneous deformation-induced hardening resulting from the alternative arrangement of bimodal Zn grains with pre-existing dislocations.Additionally,continuous strain hardening was facilitated through the interactions between deformation twins,grains and dislocations as strain accumulated,further contributing to the superior strength-ductility synergy.These findings provide valuable insights into the deformation behavior and mechanisms underlying exceptional mechanical properties of LPBF-printed Zn and its alloys for implant applications. 展开更多
关键词 laser powder bed fusion ZINC heterogeneous microstructure bimodal grains strength-ductility synergy
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Strategies for enhancing peroxymonosulfate activation by heterogenous metal-based catalysis:A review 被引量:3
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作者 Jiahao Wei Fan Li +2 位作者 Lina Zhou Dandan Han Junbo Gong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第10期12-28,共17页
Sulfate radical-advanced oxidation processes(SR-AOPs)are promising technologies for organic pollutants elimination.Heterogeneous metal-based catalysis has been widely studied and applied to activate peroxymonosulfate(... Sulfate radical-advanced oxidation processes(SR-AOPs)are promising technologies for organic pollutants elimination.Heterogeneous metal-based catalysis has been widely studied and applied to activate peroxymonosulfate(PMS)for producing sulfate radicals.Developing highly efficient catalysts is crucial for future extensive use.Importantly,the catalytic activity is mainly determined by mass and electron transfer.This paper aims to overview the recent enhancement strategies for developing heterogeneous metalbased catalysts as effective PMS activators.The main strategies,including surface engineering,structural engineering,electronic modulation,external energy assistance,and membrane filtration enhancement,are summarized.The potential mechanisms for improving catalytic activity are also introduced.Finally,the challenges and future research prospects of heterogenous metal-based catalysis in SR-AOPs are proposed.This work is hoped to guide the rational design of highly efficient heterogenous catalysts in SR-AOPs. 展开更多
关键词 PEROXYMONOSULFATE Heterogeneous catalyst Sulfate radical-advancedoxidation processes(SR-AOPs) Water treatment Enhancement strategies
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Multivariate adaptive regression splines analysis for 3D slope stability in anisotropic and heterogenous clay 被引量:2
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作者 Jim Shiau Van Qui Lai Suraparb Keawsawasvong 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期1052-1064,共13页
Little research can be found in relation to the stability of anisotropic and heterogenous soils in three dimensions.In this paper,we propose a study on the three-dimensional(3D)undrained slopes in anisotropic and hete... Little research can be found in relation to the stability of anisotropic and heterogenous soils in three dimensions.In this paper,we propose a study on the three-dimensional(3D)undrained slopes in anisotropic and heterogenous clay using advanced upper and lower bounds finite element limit analysis(FELA).The obtained stability solutions are normalized,and presented by a stability number that is a function of three geometrical ratios and two material ratios,i.e.depth ratio,length ratio,slope angle,shear strength gradient ratio and anisotropic strength ratio.Numerical results are compared with experimental data in the literature,and charts are presented to cover a wide range of design parameters.Using the multivariate adaptive regression splines(MARS)analysis,the respective influence and sensitivity of each design parameter on the stability number and the failure mechanism are investigated.An empirical equation is also developed to effectively estimate the stability number. 展开更多
关键词 3D undrained slope Limit analysis ANISOTROPY HETEROGENEITY
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Traffic Flow Prediction with Heterogenous Data Using a Hybrid CNN-LSTM Model 被引量:2
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作者 Jing-Doo Wang Chayadi Oktomy Noto Susanto 《Computers, Materials & Continua》 SCIE EI 2023年第9期3097-3112,共16页
Predicting traffic flow is a crucial component of an intelligent transportation system.Precisely monitoring and predicting traffic flow remains a challenging endeavor.However,existingmethods for predicting traffic flo... Predicting traffic flow is a crucial component of an intelligent transportation system.Precisely monitoring and predicting traffic flow remains a challenging endeavor.However,existingmethods for predicting traffic flow do not incorporate various external factors or consider the spatiotemporal correlation between spatially adjacent nodes,resulting in the loss of essential information and lower forecast performance.On the other hand,the availability of spatiotemporal data is limited.This research offers alternative spatiotemporal data with three specific features as input,vehicle type(5 types),holidays(3 types),and weather(10 conditions).In this study,the proposed model combines the advantages of the capability of convolutional(CNN)layers to extract valuable information and learn the internal representation of time-series data that can be interpreted as an image,as well as the efficiency of long short-term memory(LSTM)layers for identifying short-term and long-term dependencies.Our approach may utilize the heterogeneous spatiotemporal correlation features of the traffic flowdataset to deliver better performance traffic flow prediction than existing deep learning models.The research findings show that adding spatiotemporal feature data increases the forecast’s performance;weather by 25.85%,vehicle type by 23.70%,and holiday by 14.02%. 展开更多
关键词 Heterogeneous data traffic flow prediction deep learning CNN LSTM
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Highly active and stable porous polymer heterogenous catalysts for decomposition of formic acid to produce H_2 被引量:1
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作者 Yan Zhang Yuan Lyu +3 位作者 Yuqing Wang Cunyao Li Miao Jiang Yunjie Ding 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第2期147-151,共5页
Formic acid(FA)has attracted extensive attention as a hydrogen storage material.Here,we develop two heterogeneous catalysts based on porous organic polymers(POPs).After loading the Ru species,the catalyst bearing the ... Formic acid(FA)has attracted extensive attention as a hydrogen storage material.Here,we develop two heterogeneous catalysts based on porous organic polymers(POPs).After loading the Ru species,the catalyst bearing the triphenylphosphine ligand showed excellent performance in terms of activity and stability for the decomposition of FA to produce hydrogen. 展开更多
关键词 HETEROGENEOUS Porous organic polymer Formic acid DECOMPOSITION Hydrogen
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Efficient homogenous catalysis of CO_(2) to generate cyclic carbonates by heterogenous and recyclable polypyrazoles 被引量:1
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作者 Zhen Lu Jie He +4 位作者 Bogeng Guo Yulai Zhao Jingyu Cai Longqiang Xiao Linxi Hou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第3期110-115,共6页
The cycloaddition between CO_(2)and epoxides to produce cyclic carbonate is an attractive and efficiency pathway for the utilization of CO_(2)as C1 source.The development of catalyst to mediate cycloaddition between C... The cycloaddition between CO_(2)and epoxides to produce cyclic carbonate is an attractive and efficiency pathway for the utilization of CO_(2)as C1 source.The development of catalyst to mediate cycloaddition between CO_(2)and epoxides at low temperature and pressure is still a challenge.Herein,a series of polypyrazoles with glass transition temperature(T_(g))in the range of 42.3-52.5℃ were synthesized and served as catalyst to mediate the cycloaddition of CO_(2)and epoxides by the assistant of tetrabutylammonium bromide.The catalytic behaviors of polypyrazole on the model cycloaddition of CO_(2)to epichlorohydrin,including the reaction parameters optimization and versatility were investigated in detail,and excellent yield(99.9%)and selectivity(99%)were obtained under the optimized reaction conditions of70℃ and 1.0 MPa for 6.0 h.Noteworthily,the polypyrazole acts as homogeneous catalyst during reaction(higher than T_(g)).And under room temperature,polypyrazoles can be easily separated and recovered,which is a promising feature of a heterogeneous catalyst.Furthermore,the reaction mechanism was proposed.The DFT calculation suggested that the formation of hydrogen bond between pyrazole and epoxide greatly reduced the energy barrier,which play an important role in promoting CO_(2)cycloaddition. 展开更多
关键词 Carbon dioxide CO_(2)conversion Cyclic carbonate Heterogeneous catalysis Polypyrazole
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Distributed Optimization for Heterogenous Second⁃Order Multi⁃Agent Systems
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作者 Qing Zhang Zhikun Gong +1 位作者 Zhengquan Yang Zengqiang Chen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第4期53-59,共7页
A continuous⁃time distributed optimization was researched for second⁃order heterogeneous multi⁃agent systems.The aim of this study is to keep the velocities of all agents the same and make the velocities converge to t... A continuous⁃time distributed optimization was researched for second⁃order heterogeneous multi⁃agent systems.The aim of this study is to keep the velocities of all agents the same and make the velocities converge to the optimal value to minimize the sum of local cost functions.First,an effective distributed controller which only uses local information was designed.Then,the stability and optimization of the systems were verified.Finally,a simulation case was used to illustrate the analytical results. 展开更多
关键词 distributed optimization heterogeneous multi⁃agent system local cost function CONSENSUS
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Mechanistic alteration of polyethylene oxidation via heterogenous catalysis for enhanced fatty di-carboxylic acid yields
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作者 Huidong Lv Yi Ji +5 位作者 Wenjun Chen Yuan Xiang Yue Liu Jianrong Zeng Fei Huang Fan Zhang 《Science China Chemistry》 2025年第12期6707-6715,共9页
Conversion of polyethylene(PE) into high-value chemicals offers a sustainable approach to mitigate plastic pollution,yet achieving high selectivity and carbon efficiency remains a challenge.Herein,we report a one-pot ... Conversion of polyethylene(PE) into high-value chemicals offers a sustainable approach to mitigate plastic pollution,yet achieving high selectivity and carbon efficiency remains a challenge.Herein,we report a one-pot method for converting PE into fatty di-carboxylic acids with a mass yield of 49%.Mechanistic insights derived from in-situ electron paramagnetic resonance(EPR),infrared(IR) spectroscopy,and small-molecule probe experiments reveal that PE oxidation proceeds through oxygen insertion driven by free radicals,followed by selective cleavage of carbon–carbon(C–C) bonds.A key distinction between catalytic and non-catalytic oxidation lies in the selective cleavage of carbonyl α-C bonds,which is dramatically enhanced by the manganese oxide(MnO_(x)/SiO_(2)) catalyst that drives the formation of fatty di-carboxylic acids while minimizing other by-products.In contrast,non-catalytic oxidation of PE follows a radical-mediated mechanism,yielding a broader product spectrum with lower selectivity for fatty di-carboxylic acids and reduced carbon efficiency.These findings underscore the need for integrated protocols balancing radical formation with catalyst-driven transformations,offering a foundation for advanced catalytic systems that improve both selectivity and efficiency in PE oxidation. 展开更多
关键词 plastic upcycling polyethylene di-carboxylic acid oxidation mechanism heterogenous catalysis
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Immobilized CeO_(2)@C-N Heterogenous Structures with Enhanced Dual Modal Photodynamic/Photothermal Bacterial Inactivation Under NIR Laser Irradiation 被引量:3
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作者 Yijun Pang Zhiquan Chen +6 位作者 Didi Yang Xuke Fan Zhenda Liang Yongtao Xu Sheng Ye Jiancong Liu Li Zhou 《Journal of Analysis and Testing》 EI CSCD 2023年第3期189-203,共15页
Non-antibiotic fungicides are urgently needed due to the potential threat of drug-resistant bacteria to human health.In this research,a novel antibacterial nanoplatform based on CeO_(2)@C-N has been developed to achie... Non-antibiotic fungicides are urgently needed due to the potential threat of drug-resistant bacteria to human health.In this research,a novel antibacterial nanoplatform based on CeO_(2)@C-N has been developed to achieve rapid near-infrared(NIR)laser-induced sterilization.The prepared CeO_(2)@C-N hybrid material exhibited a nanowire-like structure,with dispersed CeO_(2)nanoparticles averaging 5 nm in size within the heterogeneous configuration.X-ray photoelectron spectroscopy(XPS)and Raman spectra revealed that the heterogenous structures have a significant amount of oxygen vacancies and defects.Notably,CeO_(2)@C-N has a narrower band gap than CeO_(2),which allows for broader absorbance extending to the NIR region.With these unique physiochemical properties,CeO_(2)@C-N could inactivate E.coli and MRSA at a low concentration(20 mg/L)under 808 nm NIR laser(1 W/cm^(2))irradiation.The excellent bactericidal activity of CeO_(2)@C-N is attributed to the combination of photodynamic and photo thermal processes,based on its excellent photo-thermal conversion property,detection of reactive oxygen species(ROS)(^(1)O_(2)and·OH)under light irradiation,and scavenger quenching experiment results.This study offers a feasible and efficient way to fabricate a highly effective antibacterial candidate. 展开更多
关键词 PHOTOTHERMAL Photodynamic heterogenous structure ANTIBACTERIAL CERIUM Carbon
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Fully Distributed Adaptive Fault-Tolerant Attitude Synchronization for a Team of Heterogenous Minisatellites 被引量:1
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作者 Hao Liu Deyuan Liu Ming Cheng 《Guidance, Navigation and Control》 2021年第4期26-47,共22页
In this paper,the fault-tolesant attitude aynchronisation aontrol problem for a team of bet-soganua man leatellita in addrsed,subject to multaple actuator faulta and uneertainties in the satellite dynamles.A fully dis... In this paper,the fault-tolesant attitude aynchronisation aontrol problem for a team of bet-soganua man leatellita in addrsed,subject to multaple actuator faulta and uneertainties in the satellite dynamles.A fully distributed adapSe fault-tokerant controlker,completely inde pendently of the knowledge of the gobal infarmation,is propoaed to achieve the desired attstude aynchranlatin.The attitade tracking aror of the glohal clased-loop eantrol aystem is paoven to onverge into a givan naighborbood of the origin ultimately.Simmlation rasults are givan to validate the afectivenas and advantaga of the propased adaptive controller dor the belerogenaou satellite formation flying team,against the infuenoe of actuator faults and umeertaintin. 展开更多
关键词 Cooperative control adaptive control uncertain system nonlinear system heterogenous minisatellites
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Accelerated heterogenous ring-opening polymerization towards well-defined helical poly(N-allyl alanine)with clickable side chains
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作者 Anyao Ma Xin Wang +1 位作者 Sunting Xuan Zhengbiao Zhang 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第6期2056-2062,共7页
Well-defined poly(N-allyl alanine)has been synthesized by heterogenous ring-opening polymerization(HROP)of less reactive N-allyl-alanine N-carboxyanhydride,using acetic acid as the catalyst and benzylamine as the init... Well-defined poly(N-allyl alanine)has been synthesized by heterogenous ring-opening polymerization(HROP)of less reactive N-allyl-alanine N-carboxyanhydride,using acetic acid as the catalyst and benzylamine as the initiator,in non-polar n-hexane.Interestingly,the polymerization exhibited typical features of living polymerization though both monomer(liquid)and polymer(solid)have minimal solubility in n-hexane.The obtained polymer showed a stable helix structure independent of the temperatures screened,as evidenced by circular dichroism analysis.Also,the preliminary study demonstrated that the side chains can be post-functionalized through thiol-ene click chemistry with quantitative conversion.Together,this work provides guidance for the development of accelerated HROP of other liquid monomers bearing low reactivity.Besides,the helical and functionalizable poly(N-allyl alanine)could be a useful“clickable platform”for the design of variable biomaterials via efficient click chemistry. 展开更多
关键词 heterogenous ring-opening polymerization controlled polymerization stable helix clickable N-substituted polypeptide di-substituted polypeptoid
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Robust and Biodegradable Heterogeneous Electronics with Customizable Cylindrical Architecture for Interference-Free Respiratory Rate Monitoring
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作者 Jing Zhang Wenqi Wang +9 位作者 Sanwei Hao Hongnan Zhu Chao Wang Zhouyang Hu Yaru Yu Fangqing Wang Peng Fu Changyou Shao Jun Yang Hailin Cong 《Nano-Micro Letters》 2026年第1期914-934,共21页
A rapidly growing field is piezoresistive sensor for accurate respiration rate monitoring to suppress the worldwide respiratory illness.However,a large neglected issue is the sensing durability and accuracy without in... A rapidly growing field is piezoresistive sensor for accurate respiration rate monitoring to suppress the worldwide respiratory illness.However,a large neglected issue is the sensing durability and accuracy without interference since the expiratory pressure always coupled with external humidity and temperature variations,as well as mechanical motion artifacts.Herein,a robust and biodegradable piezoresistive sensor is reported that consists of heterogeneous MXene/cellulose-gelation sensing layer and Ag-based interdigital electrode,featuring customizable cylindrical interface arrangement and compact hierarchical laminated architecture for collectively regulating the piezoresistive response and mechanical robustness,thereby realizing the long-term breath-induced pressure detection.Notably,molecular dynamics simulations reveal the frequent angle inversion and reorientation of MXene/cellulose in vacuum filtration,driven by shear forces and interfacial interactions,which facilitate the establishment of hydrogen bonds and optimize the architecture design in sensing layer.The resultant sensor delivers unprecedented collection features of superior stability for off-axis deformation(0-120°,~2.8×10^(-3) A)and sensing accuracy without crosstalk(humidity 50%-100%and temperature 30-80).Besides,the sensor-embedded mask together with machine learning models is achieved to train and classify the respiration status for volunteers with different ages(average prediction accuracy~90%).It is envisioned that the customizable architecture design and sensor paradigm will shed light on the advanced stability of sustainable electronics and pave the way for the commercial application in respiratory monitory. 展开更多
关键词 Wearable electronics Piezoresistive sensor HETEROGENEOUS CELLULOSE Respiratory monitoring
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Molecular mosaic of colorectal cancer:Why one classification system is no longer enough?
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作者 Sunita Ahlawat Sumanta Das 《World Journal of Gastrointestinal Oncology》 2026年第1期8-14,共7页
Colorectal cancer(CRC)is one of the most molecularly heterogeneous malignancies,with complexity that extends far beyond traditional histopathological classifications.The consensus molecular subtypes(CMS)established in... Colorectal cancer(CRC)is one of the most molecularly heterogeneous malignancies,with complexity that extends far beyond traditional histopathological classifications.The consensus molecular subtypes(CMS)established in 2015 brought a marked advancement in the taxonomy of CRC,consolidating six classification systems into four novel subtypes,which focus on vital gene expression patterns and clinical and prognostic outcomes.However,nearly a decade of clinical experience with CMS classification has revealed fundamental limitations that underscore the inadequacy of any single classification system for capturing the full spectrum of CRC biology.The inherent challenges of the current paradigm are multifaceted.In the CMS classification,mixed phenotypes that remain unclassifiable constitute 13%of CRC cases.This reflects the remarkable heterogeneity that CRC shows.The tumor budding regions reflect the molecular shift due to CMS 2 to CMS 4 switching,causing further heterogeneity.Moreover,the reliance on bulk RNA sequencing fails to capture the spatial organization of molecular signatures within tumors and the critical contributions of the tumor microenvironment.Recent technological advances in spatial transcriptomics,singlecell RNA sequencing,and multi-omic integration have revealed the limitations of transcriptome-only classifications.The emergence of CRC intrinsic subtypes that attempt to remove microenvironmental contributions,pathway-derived subtypes,and stem cell-based classifications demonstrates the field’s recognition that multiple complementary classification systems are necessary.These newer molecular subtypes are not discrete categories but biological continua,thus highlighting that the vast molecular landscape is a tapestry of interlinked features,not rigid subtypes.Multiple technical hurdles cause difficulty in implementing the clinical translation of these newer molecular subtypes,including gene signature complexity,platform-dependent variations,and the difficulty of getting and preserving fresh frozen tissue.CMS 4 shows a poor prognostic outcome among the CMS subtypes,while CMS 1 is associated with poor survival in metastatic cases.However,the predictive value for definitive therapy remains subdued.Looking forward,the integration of artificial intelligence,liquid biopsy approaches,and real-time molecular monitoring promises to enable dynamic,multi-dimensional tumor characterization.The temporal and spatial complexity can only be captured by complementary molecular taxonomies rather than a single,unified system of CRC classification.Such an approach recognizes that different clinical questions–prognosis,treatment selection,resistance prediction–may require different molecular lenses,each optimized for specific clinical applications.This editorial advocates for a revolutionary change from pursuing a single“best”classification system toward a diverse approach that welcomes the molecular mosaic of CRC.Only through such comprehensive molecular characterization can we hope to achieve the promise of precision oncology for the diverse spectrum of patients with CRC. 展开更多
关键词 Consensus molecular subtypes HETEROGENEITY Colorectal cancer intrinsic subtypes Pathway-derived subtypes Clinical translation
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Insights into the transcriptomic heterogeneity of brain endothelial cells in normal aging and Alzheimer’s disease
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作者 Qian Yue Shang Li +3 位作者 Chon Lok Lei Huaibin Wan Zaijun Zhang Maggie Pui Man Hoi 《Neural Regeneration Research》 2026年第2期569-576,共8页
Drug development for Alzheimer’s disease is extremely challenging,as demonstrated by the repeated failures of amyloid-β-targeted therapeutics and the controversies surrounding the amyloid-βcascade hypothesis.More r... Drug development for Alzheimer’s disease is extremely challenging,as demonstrated by the repeated failures of amyloid-β-targeted therapeutics and the controversies surrounding the amyloid-βcascade hypothesis.More recently,advances in the development of Lecanemab,an anti-amyloid-βmonoclonal antibody,have shown positive results in reducing brain A burden and slowing cognitive decline in patients with early-stage Alzheimer’s disease in the Phase Ⅲ clinical trial(Clarity Alzheimer’s disease).Despite these promising results,side effects such as amyloid-related imaging abnormalities(ARIA)may limit its usage.ARIA can manifest as ARIA-E(cerebral edema or effusions)and ARIA-H(microhemorrhages or superficial siderosis)and is thought to be caused by increased vascular permeability due to inflammatory responses,leading to leakages of blood products and protein-rich fluid into brain parenchyma.Endothelial dysfunction is an early pathological feature of Alzheimer’s disease,and the blood-brain barrier becomes increasingly leaky as the disease progresses.In addition,APOE4,the strongest genetic risk factor for Alzheimer’s disease,is associated with higher vascular amyloid burden,increased ARIA incidence,and accelerated blood-brain barrier disruptions.These interconnected vascular abnormalities highlight the importance of vascular contributions to the pathophysiology of Alzheimer’s disease.Here,we will closely examine recent research evaluating the heterogeneity of brain endothelial cells in the microvasculature of different brain regions and their relationships with Alzheimer’s disease progression. 展开更多
关键词 Alzheimer’s disease brain microvessel endothelial cells transcriptomic heterogeneity endothelial activation blood-brain barrier impairment neurovascular cell-cell communication
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