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Comparative study of nudged elastic band and molecular dynamics methods for diffusion kinetics in solid-state electrolytes
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作者 林啊鸣 石晶 +1 位作者 魏苏淮 孙宜阳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期96-100,共5页
Considerable efforts are being made to transition current lithium-ion and sodium-ion batteries towards the use of solid-state electrolytes.Computational methods,specifically nudged elastic band(NEB)and molecular dynam... Considerable efforts are being made to transition current lithium-ion and sodium-ion batteries towards the use of solid-state electrolytes.Computational methods,specifically nudged elastic band(NEB)and molecular dynamics(MD)methods,provide powerful tools for the design of solid-state electrolytes.The MD method is usually the choice for studying the materials involving complex multiple diffusion paths or having disordered structures.However,it relies on simulations at temperatures much higher than working temperature.This paper studies the reliability of the MD method using the system of Na diffusion in MgO as a benchmark.We carefully study the convergence behavior of the MD method and demonstrate that total effective simulation time of 12 ns can converge the calculated diffusion barrier to about 0.01 eV.The calculated diffusion barrier is 0.31 eV from both methods.The diffusion coefficients at room temperature are 4.3×10^(-9) cm^(2)⋅s^(−1) and 2.2×10^(-9) cm^(2)⋅s^(−1),respectively,from the NEB and MD methods.Our results justify the reliability of the MD method,even though high temperature simulations have to be employed to overcome the limitation on simulation time. 展开更多
关键词 nudged elastic band method molecular dynamics solid electrolyte ion transport density func-tional theory
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A Review on Engineering Design for Enhancing Interfacial Contact in Solid-State Lithium–Sulfur Batteries
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作者 Bingxin Qi Xinyue Hong +4 位作者 Ying Jiang jing shi Mingrui Zhang Wen Yan Chao Lai 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期219-252,共34页
The utilization of solid-state electrolytes(SSEs)presents a promising solution to the issues of safety concern and shuttle effect in Li–S batteries,which has garnered significant interest recently.However,the high in... The utilization of solid-state electrolytes(SSEs)presents a promising solution to the issues of safety concern and shuttle effect in Li–S batteries,which has garnered significant interest recently.However,the high interfacial impedances existing between the SSEs and the electrodes(both lithium anodes and sulfur cathodes)hinder the charge transfer and intensify the uneven deposition of lithium,which ultimately result in insufficient capacity utilization and poor cycling stability.Hence,the reduction of interfacial resistance between SSEs and electrodes is of paramount importance in the pursuit of efficacious solid-state batteries.In this review,we focus on the experimental strategies employed to enhance the interfacial contact between SSEs and electrodes,and summarize recent progresses of their applications in solidstate Li–S batteries.Moreover,the challenges and perspectives of rational interfacial design in practical solid-state Li–S batteries are outlined as well.We expect that this review will provide new insights into the further technique development and practical applications of solid-state lithium batteries. 展开更多
关键词 Solid-state lithium–sulfur batteries Solid-state electrolytes Electrode/electrolyte interface Interfacial engineering Enhancing interfacial contact
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Interfacial fusion-enhanced 11 μm-thick gel polymer electrolyte for high-performance lithium metal batteries
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作者 Ying Jiang Xinyue Hong +3 位作者 Peng Huang jing shi Wen Yan Chao Lai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期58-66,共9页
In the pursuit of ultrathin polymer electrolyte(<20 μm) for lithium metal batteries, achieving a balance between mechanical strength and interfacial stability is crucial for the longevity of the electrolytes.Herei... In the pursuit of ultrathin polymer electrolyte(<20 μm) for lithium metal batteries, achieving a balance between mechanical strength and interfacial stability is crucial for the longevity of the electrolytes.Herein, 11 μm-thick gel polymer electrolyte is designed via an integrated electrode/electrolyte structure supported by lithium metal anode. Benefiting from an exemplary superiority of excellent mechanical property, high ionic conductivity, and robust interfacial adhesion, the in-situ formed polymer electrolyte reinforced by titanosiloxane networks(ISPTS) embodies multifunctional roles of physical barrier, ionic carrier, and artificial protective layer at the interface. The potent interfacial interactions foster a seamless fusion of the electrode/electrolyte interfaces and enable continuous ion transport. Moreover, the built-in ISPTS electrolyte participates in the formation of gradient solid-electrolyte interphase(SEI) layer, which enhances the SEI's structural integrity against the strain induced by volume fluctuations of lithium anode.Consequently, the resultant 11 μm-thick ISPTS electrolyte enables lithium symmetric cells with cycling stability over 600 h and LiFePO_(4) cells with remarkable capacity retention of 96.6% after 800 cycles.This study provides a new avenue for designing ultrathin polymer electrolytes towards stable, safe,and high-energy–density lithium metal batteries. 展开更多
关键词 Ultrathin gel polymer electrolyte Integrated electrode/electrolyte structure Quasi-solid-state lithium metal battery Solid-electrolyte interphase
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Unraveling colorectal cancer prevention:The vitamin D-gut flora-immune system nexus
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作者 Zhi-Song Zhan Zu-Shun Zheng +3 位作者 jing shi Juan Chen Si-Yi Wu shi-Yan Zhang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2394-2403,共10页
Colorectal cancer(CRC)is one of the most common cancers diagnosed in the world.Although environmental and genetic factors play a major role in the pathogenesis of CRC,extensive research has suggested that vitamin D ma... Colorectal cancer(CRC)is one of the most common cancers diagnosed in the world.Although environmental and genetic factors play a major role in the pathogenesis of CRC,extensive research has suggested that vitamin D may play a pivotal role in the development of CRC.Vitamin D,primarily obtained through sunlight exposure,dietary sources,and supplements,has long been recognized for its essential functions in maintaining health,including immune regulation.This article delves into the intricate relationship between vitamin D,the immune system,gut flora,and the prevention of CRC.It presents a synthesis of epidemiological data,experimental studies,and clinical trials,highlighting the mechanisms by which vitamin D influences immune cell function,cytokine production,and inflammation.By enhancing the immune system’s surveillance and antitumor activity,vitamin D may offer a promising avenue for CRC prevention.Furthermore,this comprehensive review delves into the prospective clinical applications of vitamin D supplementation and delineates the forthcoming avenues of research in this dynamic domain.Additionally,the paper tentatively outlines a spectrum of prophylactic impacts of vitamin D on CRC,emphasizing its significant potential in reducing CRC risk through shedding light on its mechanisms,encompassing antineoplastic mechanisms,influences on the immune system,and modulation of the gut microbiome. 展开更多
关键词 Colorectal cancer Vitamin D Immune system Gut flora IMMUNOMODULATION Microbial dysbiosis Cancer prevention
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White Matter Lesions in Young-Middle Aged Migraineurs with Patent Foreman Ovale: A Case-Control Study
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作者 Yang Hua Jinyu Sun +3 位作者 Yuxuan Lou Hao Zhang jing shi Wei Sun 《Congenital Heart Disease》 SCIE 2024年第3期279-291,共13页
Background:White matter lesion(WML)is common in aging brain and is associated with cognitive impairment and dementia.However,recent studies reported an association between patent foramen ovale(PFO)and WML in migraineu... Background:White matter lesion(WML)is common in aging brain and is associated with cognitive impairment and dementia.However,recent studies reported an association between patent foramen ovale(PFO)and WML in migraineurs,especially in young,middle-aged migraineurs.Our retrospective,case-control study aims to describe the clinical characteristics of WML in this population and to explore potential risk factors.Methods:226 patients with migraine and PFO were consecutively initially screened.Relevant factors were selected by the least absolute shrinkage and selection operator(LASSO)regression and multivariable logistic regression model.A Nomogram was employed to visualize the prediction model conveniently.The discrimination and calibration abilities were evaluated using the Receiver Operating Characteristic(ROC)curve,the Hosmer-Lemeshow test,and calibration curves.Results:One hundred and nineteen participants were ultimately enrolled in our study,with a median age of 36.9±12.7 years and 80.7%of females.Brain magnetic resonance imaging MRI showed 67(56.3%)patients had WML,whereas 52(43.7%)patients were categorized into the non-WML group.LASSO regression screened out potential variables and subsequent multivariate analysisfinally identified age,mean platelet volume,andfibri-nogen(FIB)as independent predictive factors of WML.The area under the ROC curve(AUC)was 0.807.Hos-mer-Lemeshow test and calibration curve verified a consistency between the predicted and actual probability.Conclusion:The predictive nomogram established and validated in our study may assist clinicians in screening WML among young middle-aged migraineurs with PFO and developing individualized preventive and treatment strategies. 展开更多
关键词 White matter lesion MIGRAINE patent foreman ovale NOMOGRAM predictive model
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Lipid-lowering effects of gefarnate in statin-treated patients with residual hypertriglyceridemia:a randomized controlled study
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作者 jing shi Ming-Lu XU +14 位作者 Mei-Jiao HE Wan-Lan BO Hai-Yu ZHANG Dang-Hui SUN Ding-Yu WANG Xiao-Yu WANG Qun SHAO Yu-Jiao PAN Yu ZHANG Chen-Guang DAI jing-Ying WANG Lin-Wei ZHANG Guang-Zhong LIU Yue LI for the GPROT Study Group 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第8期791-798,共8页
BACKGROUND The prevention of coronary artery disease(CAD)faces dual challenges:the aspirin-induced gastrointestinal injury,and the residual cardiovascular risk after statin treatment.Geraniol acetate(Gefarnate)is an a... BACKGROUND The prevention of coronary artery disease(CAD)faces dual challenges:the aspirin-induced gastrointestinal injury,and the residual cardiovascular risk after statin treatment.Geraniol acetate(Gefarnate)is an anti-ulcer drug.It was reported that geraniol might participate in lipid metabolism through a variety of pathways.The aim of this study was to assess the lipid-lowering effects of gefarnate in statin-treated CAD patients with residual hypertriglyceridemia.METHODS In this prospective,open-label,randomized,controlled trial,69 statin-treated CAD patients with residual hypertriglyceridemia were randomly assigned to gefarnate group and control group,received gefarnate(100 mg/3 times a day)combined with statin and statin alone,respectively.At baseline and after one-month treatment,the levels of plasma triglyceride,high-density lipoprotein cholesterol(HDL-C),low-density lipoprotein cholesterol(LDL-C)and total cholesterol were tested.RESULTS After one-month gefarnate treatment,triglyceride level was significantly lowered from 2.64 mmol/L to 2.12 mmol/L(P=0.0018),LDL-C level lowered from 2.7 mmol/L to 2.37 mmol/L(P=0.0004),HDL-C level increased from 0.97 mmol/L to 1.17mmol/L(P=0.0228).Based on statin therapy,gefarnate could significantly reduce the plasma triglyceride level(P=0.0148)and increase the plasma HDL-C level(P=0.0307).Although the LDL-C and total cholesterol levels tended to decrease,there was no statistically significant difference.CONCLUSIONS The addition of gefarnate to statin reduced triglyceride level and increased HDL-C level to a significant extent compared to statin alone in CAD patients with residual hypertriglyceridemia.This suggested that gefarnate might provide the dual benefits of preventing gastrointestinal injury and lipid lowering in CAD patients. 展开更多
关键词 NAT ALONE LIPID
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Diagnostic efficacy of virtual organ computer-assisted analysis in measuring the volume ratio of subchorionic hematoma with serum progesterone
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作者 Lin-Ling Shen jing shi +2 位作者 Chang-Wei Ding Gao-Le Dai Qi Ma 《World Journal of Clinical Cases》 SCIE 2024年第17期3053-3060,共8页
BACKGROUND Subchorionic hematoma(SCH)is a common complication in early pregnancy characterized by the accumulation of blood between the uterine wall and the chorionic membrane.SCH can lead to adverse pregnancy outcome... BACKGROUND Subchorionic hematoma(SCH)is a common complication in early pregnancy characterized by the accumulation of blood between the uterine wall and the chorionic membrane.SCH can lead to adverse pregnancy outcomes such as miscarriage,preterm birth,and other complications.Early detection and accurate assessment of SCH are crucial for appropriate management and improved pregnancy outcomes.AIM To evaluate the diagnostic efficacy of virtual organ computer-assisted analysis(VOCAL)in measuring the volume ratio of SCH to gestational sac(GS)combined with serum progesterone on early pregnancy outcomes in patients with SCH.METHODS A total of 153 patients with SCH in their first-trimester pregnancies between 6 and 11 wk were enrolled.All patients were followed up until a gestational age of 20 wk.The parameters of transvaginal two-dimensional ultrasound,including the circumference of SCH(Cs),surface area of SCH(Ss),circumference of GS(Cg),and surface area of GS(Sg),and the parameters of VOCAL with transvaginal three-dimensional ultrasound,including the three-dimensional volume of SCH(3DVs)and GS(3DVg),were recorded.The size of the SCH and its ratio to the GS size(Cs/Cg,Ss/Sg,3DVs/3DVg)were recorded and compared.RESULTS Compared with those in the normal pregnancy group,the adverse pregnancy group had higher Cs/Cg,Ss/Sg,and 3DVs/3DVg ratios(P<0.05).When 3DVs/3DVg was 0.220,the highest predictive performance predicted adverse pregnancy outcomes,resulting in an AUC of 0.767,and the sensitivity,specificity were 70.2%,75%respectively.VOCAL measuring 3DVs/3DVg combined with serum progesterone gave a diagnostic AUC of 0.824 for early pregnancy outcome in SCH patients,with a high sensitivity of 82.1%and a specificity of 72.1%,which showed a significant difference between AUC.CONCLUSION VOCAL-measured 3DVs/3DVg effectively quantifies the severity of SCH,while combined serum progesterone better predicts adverse pregnancy outcomes. 展开更多
关键词 Subchorionic hematoma Virtual organ computer-assisted analysis Gestational sac Serum progesterone Ultrasound parameters Adverse pregnancy outcomes
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Prevalence and Related Factors of Falls among the Elderly in an Urban Community of Beijing 被引量:7
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作者 PU-LIN YU ZHAO-HUI QIN +4 位作者 jing shi JUAN ZHANG MEI-ZHE XIN ZHENG-LAI WU ZHEN-QIU SUN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第3期179-187,共9页
Objective To understand the prevalence, consequences and risk factors of falls among urban community-dwelling elderly in Beijing. Methods A cross-sectional study was conducted in Longtan Community, Beijing. A total of... Objective To understand the prevalence, consequences and risk factors of falls among urban community-dwelling elderly in Beijing. Methods A cross-sectional study was conducted in Longtan Community, Beijing. A total of 1512 individuals aged 60 years or over were selected by stratified cluster sampling. Data regarding the frequency of falls in the previous year, as well as circumstances, consequence and related factors of falls were collected from the elderly through face-to-face interviews with questionnaires in their home. Results The prevalence of falls was 18.0% on the average among 1512 participants, higher in women (20.1%) than in men (14.9%) (P=0.006), and increased with age (Х^2 for trend=10.37, P=0.001). The total rate of falls-induced injuries among the fallers was 37.7%. Falls usually resulted in soft-tissues bruises (58.7%), fear of repeated episodes of falls (58.8%), loss of independence and confidence in movement (35.7%) and even in hip fracture. In addition to the burden of medical care, falls also generated a big economic burden. Occurrence of falls was significantly associated with both intrinsic and extrinsic factors. The related factors of falls in the elderly included age≥60-70 years, femininity, less physical activities, fear of future falls, living alone, severely impaired vision, health problem-impacted activities of daily living, chronic diseases (diabetes, hypertension, postural hypotension, stroke sequela, cataract, arthritis, dementia and depression), medications (psychoactive, anti-diabetic), gait imbalance, high bed and faintly-lighted stairway. Conclusion The prevalence of falls among urban community-dwelling elderly in Beijing is closely associated with significant associated with intrinsic and extrinsic factors. Efforts to prevent falls in the elderly should be made at community level. 展开更多
关键词 FALLS PREVALENCE Old people PREVENTION
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The relationship between platelet endothelial cell adhesion molecule-1 and paraquat-induced lung injury in rabbits 被引量:7
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作者 jing shi Chun-lin Hu +2 位作者 Yu-feng Gao Xiao-xing Liao Hope Xu 《World Journal of Emergency Medicine》 CAS 2012年第1期60-64,共5页
BACKGROUND:Platelet endothelial cell adhesion molecule-1(PECAM-1),also known as CD31,is mainly distributed in vascular endothelial cells.Studies have shown that PECAM-1 is a very significant indicator of angiogenesis,... BACKGROUND:Platelet endothelial cell adhesion molecule-1(PECAM-1),also known as CD31,is mainly distributed in vascular endothelial cells.Studies have shown that PECAM-1 is a very significant indicator of angiogenesis,and has been used as an indicator for vascular endothelial cells.The present study aimed to explore the relationship between the expression of PECAM-1 and the degree of acute lung injury(ALI) and fibrosis in paraquat(PQ) induced lung injury in rabbits.METHODS:Thirty-six adult New Zealand rabbits were randomly divided into three groups(12rabbits in each group) according to PQ dosage:8 mg/kg(group A),16 mg/kg(group B),and 32 mg/kg(group C).After PQ infusion,the rabbits were monitored for 7 days and then euthanized.The lungs were removed for histological evaluation.Masson staining was used to determine the degree of lung fibrosis(LF),and semi-quantitative immune-histochemistry analysis to determine the expression of PECAM-1.Pearson's product-moment correlation analysis was performed to evaluate the relationship between the expression of PECAM-1 and the extent of lung injuries expressed by ALI score and degree of LF.RESULTS:Rabbits in the three groups showed apparent poisoning.The rabbits survived longer in group A than in groups B and C(6.47±0.99 days vs.6.09±1.04 days vs.4.77±2.04 days)(P<0.05).ALI score was lower in group A than in groups B and C(8.33±1.03 vs.9.83±1.17 vs.11.50±1.38)(P<0.05),and there was statistically significant difference between group B and group C(P=0.03).LF was slighter in group A than in groups B and C(31.09%±2.05%vs.34.37%±1.62%vs.36.54%±0.44%)(P<0.05),and there was statistically significant difference between group B and group C(P=0.026).The PEACAM-1 expression was higher in group A than in groups B and C(20.31%±0.70%vs.19.34%±0.68%vs.18.37%±0.46%)(P<0.05),and there was statistically significant difference between group B and group C(P=0.017).Pearson's correlation analysis showed that the expression of PECAM-1 was negatively correlated to both ALI score(Coe=-0.732,P=0.001)and degree of LF(Coe=-0.779,P<0.001).CONCLUSIONS:The PECAM-1 expression significantly decreases in New Zealand rabbits after PQ poisoning,and the decrease is dose-dependent.The PECAM-1 expression is negatively correlated with ALI score and LF,showing a significant role in the development of lung injuries induced by PQ. 展开更多
关键词 Platelet endothelial cell adhesion molecule-1 PARAQUAT Acute lung injury Lung fibrosis
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Treatment of Single Level Lumbar Spondylolisthesis with Lumbar Interbody Fusion via Oblique Lateral Approach (OLIF)
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作者 Jinpeng Zheng Dun Liu +3 位作者 jing shi Han Wu Ping Cao Bing Hu 《Surgical Science》 2023年第1期46-54,共9页
Objectives: To investigate the effect of lumbar interbody fusion via the oblique lateral approach (OLIF) in the treatment of single level lumbar spondylolisthesis. Methods: Retrospective analysis was made on 32 cases ... Objectives: To investigate the effect of lumbar interbody fusion via the oblique lateral approach (OLIF) in the treatment of single level lumbar spondylolisthesis. Methods: Retrospective analysis was made on 32 cases of single level lumbar spondylolisthesis treated by lumbar interbody fusion via the oblique lateral approach from July 2020 to July 2021. 14 males and 18 females;the age was (66.5 ± 11.5) years (55 - 82 years). 1) The operation time, intraoperative blood loss and complications were recorded;2) the scores of visual analog scale. VAS and Oswestry disability index (ODI) of low back pain and lower limb pain were collected before operation and at the last follow-up;by observing the imaging data, the height of the intervertebral space, the anterior convex angle of the intervertebral space, the anterior convex angle of the lumbar spine, the sagittal diameter of the dural sac and the spondylolisthesis were measured. Results: All patients successfully completed the operation, the average operation time was (103.9 ± 21.1) min, the average intraoperative bleeding volume was (72.3 ± 16.4) ml. There was no vascular injury during the operation, no infection occurred in all surgical incisions, and Class I/A healing was achieved. The VAS scores of low back pain and leg pain before operation and at the last follow-up were lower than those before operation, and the difference was statistically significant (P < 0.05);the ODI at the last follow-up was lower than that before operation, and the difference was statistically significant (P < 0.05). At the last follow-up, the height of intervertebral space, the height of intervertebral foramen and the sagittal diameter of dural sac were greater than those before operation, with statistically significant differences (P < 0.05);the spondylolisthesis rate at the last follow-up was lower than that before operation, with a statistically significant difference (P < 0.05). Left thigh surface numbness occurred in 2 cases (6.3%) and disappeared after 1 week;Hip flexion weakness occurred in 1 case (0.03%), which recovered after 12 days;there were no complications such as retroperitoneal hematoma, ureteral injury, retrograde ejaculation, intestinal and lumbar plexus injury. Conclusion: The early clinical effect of OLIF in the treatment of single level lumbar spondylolisthesis is significant. This surgical method is minimally invasive, safe and effective, which can significantly reduce the amount of intraoperative bleeding and reduce the risk of postoperative complications. Its main working principle is to make the annulus fibrosus, posterior longitudinal ligament and ligamentum flavum shrink and recover the height of the intervertebral space through decompression, loosening and stretching of the intervertebral space, so as to achieve the reduction of the slipped vertebral body, increase the height of the intervertebral foramen Enlarge the spinal canal volume and eliminate dynamic compression to play an indirect decompression role, improve the symptoms of low back and leg pain, and reconstruct the stability of the spine through interbody fusion. 展开更多
关键词 Oblique Lateral Approach Lumbar Interbody Fusion Single Segment Lumbar Spondylolisthesis
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氧化还原活性配体的电子效应对钌催化水氧化反应的影响
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作者 石靖 郭煜华 +2 位作者 谢飞 章名田 张洪涛 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第9期271-279,共9页
水氧化(2H_(2)O→4e^(-)+4H^(+)+O_(2)↑)是自然以及人工光合作用系统中的关键半反应,为还原过程提供反应所必需的质子和电子.但水氧化反应在热力学和动力学上的固有挑战以及对O-O键生成步骤的有限机理认识,使其成为构筑高效人工光合系... 水氧化(2H_(2)O→4e^(-)+4H^(+)+O_(2)↑)是自然以及人工光合作用系统中的关键半反应,为还原过程提供反应所必需的质子和电子.但水氧化反应在热力学和动力学上的固有挑战以及对O-O键生成步骤的有限机理认识,使其成为构筑高效人工光合系统的瓶颈.为此,人们开发了大量的金属催化剂,利用金属中心活化水分子,并生成活性金属氧物种以促进O-O键的生成.其间,金属中心往往需要达到极高的氧化态,进而导致生成的高价金属氧化物具有极高的催化活性,极易诱导催化剂降解等副反应的发生,难以兼顾活性和稳定性.因此,深入认识和理解水氧化反应的催化过程及O-O键的生成机制是突破该领域瓶颈的重点.氧化还原活性配体与金属的协同作用被认为是调节电荷累积过程、平衡催化剂活性与稳定性的有效策略,受到了广泛的关注.然而,氧化还原活性配体调节金属催化中心活性的机理仍有待进一步阐明.近期,本研究组发展了一类具有氧化活性配体的单核钌水氧化催化剂[(L_H^((N5-)))Ru^(Ⅲ)-OH]^(+),初步机理研究表明配体的氧化有效地承担了电荷累积,提出了水分子亲核进攻Ru~Ⅳ=O形成O-O键的反应机制.但氧化还原配体的电子效应如何影响催化中心的反应性及其调控规律有待深入研究.本文设计了一系列具有不同取代基的单核钌催化剂[(L_R^(N5-))Ru^(Ⅲ)-OH]^(+)(R=OMe,3a;Me,3b;H,3c;F,3d;CF_(3),3e),利用电化学、线性自由能关系以及理论计算等方法考察了配体的电子效应对催化中心活性的调控规律,并为配体协助下的Ru~Ⅳ=O催化O-O成键提供了实验证据.电化学测试结果表明,在碳酸丙烯酯溶液和0.1 mol/L磷酸缓冲溶液(pH=7.0)中催化剂均表现出三个连续的氧化峰,并且配体的取代基效应对其氧化还原电势和催化行为均有显著影响.但氧化还原电势与取代基常数(σ_(para))的线性相关结果表明,三个连续的氧化过程表现出了不同的电子效应依赖程度,第三个氧化过程对电子效应的依赖程度明显高于前两个.因此三个氧化过程依次被归属为金属中心Ru~(Ⅲ/Ⅱ)(E(Ru~Ⅲ-OH/Ru^(Ⅱ)-OH_(2))),Ru^(Ⅳ/Ⅲ)(E(Ru~Ⅳ=O/Ru~Ⅲ-OH))以及配体中心L^(+·)/L(E{[(L^(N5-))^(+·)Ru^(Ⅳ)=O]^((2+))/[(L^(N5-))Ru^(Ⅳ)=O]^(+}))的氧化.催化剂性能测试结果表明,催化活性和催化过电位均与配体取代基常数(σ_(para))具有良好的线性关系.随着取代基吸电子能力的增强,催化剂的转化频率逐渐增大;随着取代基给电子能力的增加,催化剂的催化过电位也逐渐降低.实验结果表明,氧化还原配体的电子效应可以有效地调控催化剂的催化活性与过电位.电位与pH相关实验结果表明,起始的[(L_R~(N5-))Ru~Ⅲ-OH]~+催化剂经历两电子、一质子转移后形成配体氧化的活性中间体[(L^((N5-)))^(+·)Ru^(Ⅳ)=O]^(2+),并进一步与水反应生成O-O键.H/D同位素动力学效应及缓冲溶液碱效应证实了水分子亲核进攻[(L^(N5-))^(+·)Ru^(Ⅳ)=O]^(2+)形成O-O键的机制.理论计算研究表明,配体的取代基有效调节了该O-O成键过程的活化能,进而调控了该决速步的反应速率和催化过电位.综上,本文详细阐释了如何通过氧化还原活性配体获得易生成、高活性的金属氧物种,并调控Ru~Ⅳ=O中间体对O-O键生成的催化活性,也为具有低过电位的水氧化催化剂的理性设计和机制研究提供了参考. 展开更多
关键词 人工光合作用 水氧化反应 氧化还原活性配体 Ru^(IV)=O中间体 取代基效应
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All-cellulose-based quasi-solid-state supercapacitor with nitrogen and boron dual-doped carbon electrodes exhibiting high energy density and excellent cyclic stability 被引量:1
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作者 Kaixuan Li Ping Li +6 位作者 Zining Sun jing shi Minghua Huang jingwei Chen Shuai Liu Zhicheng shi Huanlei Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第4期1091-1101,共11页
The key to construct high-energy supercapacitors is to maximize the capacitance of electrode and the voltage of the device. Realizing this purpose by utilizing sustainable and low-cost resources is still a big challen... The key to construct high-energy supercapacitors is to maximize the capacitance of electrode and the voltage of the device. Realizing this purpose by utilizing sustainable and low-cost resources is still a big challenge. Herein, N, B co-doped carbon nanosheets are obtained through the proposed dual-template assisted approach by using methyl cellulose as the precursor. Due to the synergistic effects form the high surface area with the hierarchical porous structure, N/B dual doping, and a high degree of graphitization, the resultant carbon electrode exhibits a high capacitance of 572 F g^(-1)at 0.5 A g^(-1)and retains 281 F g^(-1)at 50 A g^(-1)in an acidic electrolyte. Furthermore, the symmetric device assembled using bacterial cellulose-based gel polymer electrolyte can deliver high energy density of 43 W h kg^(-1)and excellent cyclability with 97.8% capacity retention after 20 000 cycles in “water in salt” electrolyte. This work successfully realizes the fabrication of high-performance allcellulose-based quasi-solid-state supercapacitors, which brings a cost-effective insight into jointly designing electrodes and electrolytes for supporting highly efficient energy storage. 展开更多
关键词 Dual doping Carbon materials Quasi-solid-state supercapacitor Cellulose Hierarchical structure
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Optimization of large-area YBa_(2)Cu_(3)O_(7-δ)thin films by pulsed laser deposition for planar microwave devices 被引量:1
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作者 熊沛雨 陈赋聪 +8 位作者 冯中沛 杨景婷 夏钰东 袁跃峰 王旭 袁洁 吴云 石兢 金魁 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期186-190,共5页
This paper presents high quality YBa_(2)Cu_(3)O_(7-δ)(YBCO)thin films on LaAlO_(3)substrate for microwave devices prepared by pulsed laser deposition(PLD).The double-sided YBCO films cover a large area and have been ... This paper presents high quality YBa_(2)Cu_(3)O_(7-δ)(YBCO)thin films on LaAlO_(3)substrate for microwave devices prepared by pulsed laser deposition(PLD).The double-sided YBCO films cover a large area and have been optimized for key parameters relevant to microwave device applications,such as surface morphology and surface resistance(R_(s)).This was achieved by improving the target quality and increasing the oxygen pressure during deposition,respectively.To evaluate the suitability of the YBCO films for microwave devices,a pair of microwave filters based on microstrip fabricated on films from this work and a commercial company were compared.The results show that the YBCO films in this work could completely meet the requirements for microwave devices. 展开更多
关键词 YBCO films pulsed laser deposition(PLD) surface resistance microwave devices
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Extremely Anisotropic Thermoelectric Properties of SnSe Under Pressure 被引量:1
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作者 Wei Cao Ziyu Wang +2 位作者 Ling Miao jing shi Rui Xiong 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第3期58-65,共8页
SnSe has attracted extensive attention due to its ultralow thermal conductivity and excellent thermoelectric properties.In this work,pressure-induced thermoelectric properties of Pnma SnSe are investigated via first-p... SnSe has attracted extensive attention due to its ultralow thermal conductivity and excellent thermoelectric properties.In this work,pressure-induced thermoelectric properties of Pnma SnSe are investigated via first-principles calculations.We uncover distinct energy isosurfaces topology transition of conduction band by applying pressure.The newly created conduction band valley caused by pressure has a distinct anisotropic shape compared to the old one.Inducing pressure can greatly enhance the anisotropy of electronic transport properties of the n-type Pnma SnSe.Furthermore,the lattice thermal conductivity also exhibits anisotropic behavior under pressure due to a special collaged phonon mode.The pressure-induced lattice thermal conductivity along the a-axis shows a slower growth trend than that along the b-axis and c-axis.The optimal ZT value of the n-type Pnma SnSe along the a-axis can reach 1.64 at room temperature.These results would be helpful for designing the Pnma SnSe-based materials for the potential thermoelectric and valleytronic applications. 展开更多
关键词 first-principles calculations PRESSURE SnSe thermoelectric materials
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英国普通学校融合教育支持体系及启示
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作者 孙泽 景时 张嫱 《绥化学院学报》 2023年第4期26-31,共6页
进入21世纪,英国政府为了提升融合教育的质量,在《特殊教育需要实施章程》等政策中确立了“为特殊需要学生提供服务是普通学校的责任”的原则,进而构建完善的融合教育支持体系。英国普通学校的融合教育支持体系具有鲜明特征,具体包括“... 进入21世纪,英国政府为了提升融合教育的质量,在《特殊教育需要实施章程》等政策中确立了“为特殊需要学生提供服务是普通学校的责任”的原则,进而构建完善的融合教育支持体系。英国普通学校的融合教育支持体系具有鲜明特征,具体包括“:反歧视”的融合学校文化“、基于普通教育”的个别化教育服务“、以特殊教育协调员为核心”的人员合作。在英国普通学校融合教育支持体系的经验启示下,我国普通学校资源教室建设应该从“资源教室”走向“资源学校”、从“个别化教育计划”走向“普通教育改进”、从“资源教师”走向“多方合作”。 展开更多
关键词 英国 融合教育 支持体系 资源教室
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Local-to-Global Causal Reasoning for Cross-Document Relation Extraction
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作者 Haoran Wu Xiuyi Chen +3 位作者 Zefa Hu jing shi Shuang Xu Bo Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第7期1608-1621,共14页
Cross-document relation extraction(RE),as an extension of information extraction,requires integrating information from multiple documents retrieved from open domains with a large number of irrelevant or confusing nois... Cross-document relation extraction(RE),as an extension of information extraction,requires integrating information from multiple documents retrieved from open domains with a large number of irrelevant or confusing noisy texts.Previous studies focus on the attention mechanism to construct the connection between different text features through semantic similarity.However,similarity-based methods cannot distinguish valid information from highly similar retrieved documents well.How to design an effective algorithm to implement aggregated reasoning in confusing information with similar features still remains an open issue.To address this problem,we design a novel local-toglobal causal reasoning(LGCR)network for cross-document RE,which enables efficient distinguishing,filtering and global reasoning on complex information from a causal perspective.Specifically,we propose a local causal estimation algorithm to estimate the causal effect,which is the first trial to use the causal reasoning independent of feature similarity to distinguish between confusing and valid information in cross-document RE.Furthermore,based on the causal effect,we propose a causality guided global reasoning algorithm to filter the confusing information and achieve global reasoning.Experimental results under the closed and the open settings of the large-scale dataset Cod RED demonstrate our LGCR network significantly outperforms the state-ofthe-art methods and validate the effectiveness of causal reasoning in confusing information processing. 展开更多
关键词 Causal reasoning cross document graph reasoning relation extraction(RE)
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Preliminary Evaluation of Hemodynamic Effects of Fontan Palliation on Renal Artery Using Computational Fluid Dynamics
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作者 Jinlong Liu jing shi +6 位作者 Weiru Luo Zhirong Tong Lefei Yang Peixuan Sun Tianyi Li Jun Du Qian Wang 《Congenital Heart Disease》 SCIE 2023年第1期41-55,共15页
Background:The assessment of renal function is important to the prognosis of patients needing Fontan palliation due to the reconstructed compromised circulation.To know the relationship between the kidney perfusion an... Background:The assessment of renal function is important to the prognosis of patients needing Fontan palliation due to the reconstructed compromised circulation.To know the relationship between the kidney perfusion and hemodynamic characteristics during surgical design could reduce the risk of acute kidney injury(AKI)and the postoperative complications.However,the issue is still unsolved because the current clinical evaluation methods are unable to predict the hemodynamic changes in renal artery(RA).Methods:We reconstructed a three-dimensional(3D)vascular model of a patient requiring Fontan palliation.The technique of computational fluid dynamics(CFD)was utilized to explore the changes of RA hemodynamics under different possible blood flow rates.The relationship between the kidney perfusion and hemodynamic characteristics was investigated.Results:The calculated results indicated the declined tendency of the pressure and pressure drop as the flow rate decreased.When the flow rate decreased to two-thirds of its baseline,both the pressure of left renal artery(LRA)and the pressure of right renal artery(RRA)dipped below 50%,and the pressure of RRA fell more quickly than that of LRA.Uneven distribution of WSS was observed on the trunk of RA,and the lowest WSS was found at the distal of RA.The average WSS in RA dropped to around 50%as the flow rate reached one-third of its baseline.Conclusions:As a promising approach,CFD can be utilized to quantitatively evaluate the hemodynamic characteristics of RA and contribute to offsetting the drawbacks of clinical assessments of renal function,to help realize better prognosis for the patients with Fontan palliation. 展开更多
关键词 Renal artery Fontan palliation HEMODYNAMICS computational fluid dynamics surgical design
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Constructing Carbon Nanobubbles with Boron Doping as Advanced Anode for Realizing Unprecedently Ultrafast Potassium Ion Storage
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作者 Huanyu Liang Zining Sun +7 位作者 Mingrui Zhang Wei Hu jing shi jingwei Chen Weiqian Tian Minghua Huang jingyi Wu Huanlei Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期248-257,共10页
Carbonaceous material with favorable K^(+)intercalation feature is considered as a compelling anode for potassium-ion batteries(PIBs).However,the inferior rate performance and cycling stability impede their large-scal... Carbonaceous material with favorable K^(+)intercalation feature is considered as a compelling anode for potassium-ion batteries(PIBs).However,the inferior rate performance and cycling stability impede their large-scale application.Here,a facile template method is utilized to synthesize boron doping carbon nanobubbles(BCNBs).The incorporation of boron into the carbon structure introduces abundant defective sites and improves conductivity,facilitating both the intercalation-controlled and capacitivecontrolled capacities.Moreover,theoretical calculation proves that boron doping can effectively improve the conductivity and facilitate electrochemical reversibility in PIBs.Correspondingly,the designed BCNBs anode delivers a high specific capacity(464 mAh g^(-1)at 0.05 A g^(-1))with an extraordinary rate performance(85.7 mAh g^(-1)at 50 A g^(-1)),and retains a considerable capacity retention(95.2%relative to the 100th charge after 2000 cycles).Besides,the strategy of pre-forming stable artificial inorganic solid electrolyte interface effectively realizes high initial coulombic efficiency of 79.0%for BCNBs.Impressively,a dual-carbon potassium-ion capacitor coupling BCNBs anode displays a high energy density(177.8 Wh kg^(-1)).This work not only shows great potential for utilizing heteroatom-doping strategy to boost the potassium ion storage but also paves the way for designing high-energy/power storage devices. 展开更多
关键词 high electrical conductivity potassium ion batteries potassium ion storage superior reversibility
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基于DE-GPR的数控机床切削能耗预测 被引量:4
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作者 宋李俊 潘安大 +1 位作者 jing shi 陈猛 《重庆理工大学学报(自然科学)》 CAS 北大核心 2018年第11期52-57,共6页
数控机床切削加工过程中能量源多、工况复杂多变,使其能耗难以预测。基于数控机床切削原理,分析切削参数对切削加工过程能耗的影响;采用高斯过程回归方法,建立一种以数据为驱动的数控机床能耗预测模型;引入差分进化算法对其进行优化。... 数控机床切削加工过程中能量源多、工况复杂多变,使其能耗难以预测。基于数控机床切削原理,分析切削参数对切削加工过程能耗的影响;采用高斯过程回归方法,建立一种以数据为驱动的数控机床能耗预测模型;引入差分进化算法对其进行优化。通过数控机床加工数据仿真,验证了所建模型的有效性和可行性。 展开更多
关键词 数控机床 能耗预测 高斯过程回归 差分进化
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Study on the Effect of Different Modified Zeolite to Phosphorus Activation in Red Soil 被引量:2
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作者 jing shi Naiming Zhang +1 位作者 Chenguang Zhang Boxian Wei 《Journal of Environmental Protection》 2016年第13期2036-2046,共12页
The activation of soil-fixed phosphorus is a long-term concern in soil science. In order to enhance the activation effect to soil-fixed phosphorus in red soil, different modified zeolite, through physical, chemical me... The activation of soil-fixed phosphorus is a long-term concern in soil science. In order to enhance the activation effect to soil-fixed phosphorus in red soil, different modified zeolite, through physical, chemical method and the associated both physics and chemistry, was used in this paper. The results showed as following: 1) the activated ability to soil-fixed phosphorus in red soil for modified zeolite was higher than the common one signally. Order of the ability for all kinds of modification zeolite in absolute activation amount and activation rate was: Modified in high temperature ammonium saturated zeolite > Ammonium saturated zeolite > Modified in high temperature zeolite > Common zeolite. 2) The increasing rate of modified phosphorus in high temperature ammonium saturated zeolite and ammonium saturated zeolite had a decline trend with time postponed while that for modified phosphorus in high temperature zeolite and routine zeolite was rising gradually with time postponed. For ammonium saturated zeolite, the increasing rate of phosphorus in low available phosphorus content red soil was significantly faster than that in red soil with the higher content of available phosphorus. 3) The activation rate for the same modified zeolite showed difference in different phosphorus level soil. The order is: SP<sub>high</sub> > SP<sub>medium</sub> > SP<sub>low</sub>. 展开更多
关键词 ACTIVATION PHOSPHORUS Red Soil ZEOLITE
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