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Augmenting prostate magnetic resonance imaging reporting to incorporate diagnostic recommendations based upon clinical risk calculators
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作者 Karisma Gupta Jordan D Perchik +2 位作者 Andrew M Fang Kristin K Porter Soroush Rais-Bahrami 《World Journal of Radiology》 2022年第8期249-255,共7页
Risk calculators have offered a viable tool for clinicians to stratify patients at risk of prostate cancer(PCa)and to mitigate the low sensitivity and specificity of screening prostate specific antigen(PSA).While init... Risk calculators have offered a viable tool for clinicians to stratify patients at risk of prostate cancer(PCa)and to mitigate the low sensitivity and specificity of screening prostate specific antigen(PSA).While initially based on clinical and demographic data,incorporation of multiparametric magnetic resonance imaging(MRI)and the validated prostate imaging reporting and data system suspicion scoring system has standardized and improved risk stratification beyond the use of PSA and patient parameters alone.Biopsy-naïve patients with lower risk profiles for harboring clinically significant PCa are often subjected to uncomfortable,invasive,and potentially unnecessary prostate biopsy procedures.Incorporating risk calculator data into prostate MRI reports can broaden the role of radiologists,improve communication with clinicians primarily managing these patients,and help guide clinical care in directing the screening,detection,and risk stratification of PCa. 展开更多
关键词 Prostatic adenocarcinoma Multiparametric magnetic resonance imaging NOMOGRAMS Risk calculators BIOPSY
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Risk calculators for hepatocellular carcinoma in patients affected with chronic hepatitis B in Asia 被引量:5
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作者 Hwai-I Yang Mei-Hsuan Lee +1 位作者 Jessica Liu Chien-Jen Chen 《World Journal of Gastroenterology》 SCIE CAS 2014年第20期6244-6251,共8页
Risk calculators are widely used in many clinical fields, and integrate several important risk factors through the conversion of a risk function into a single measure of risk. Several studies have been carried out to ... Risk calculators are widely used in many clinical fields, and integrate several important risk factors through the conversion of a risk function into a single measure of risk. Several studies have been carried out to create risk calculators for the prediction of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB). Most of them were hospital-based, with limited sample sizes and insufficient external validation. These study groups collaborated to establish the REACH-B risk score, which incorporated five clinical variables to predict HCC risk. This risk score was then validated in international clinical cohorts. Evidence suggests that quantitative serum HBsAg level provides additional predictability of HCC, especially in patients with low levels of hepatitis B virus DNA. This novel marker was incorporated into a risk calculator and was internally validated. This tool will hopefully be externally validated in the near future. Risk calculators can be used to support clinical practice, and to establish preventive measures; several &#x0201c;off-label&#x0201d; extension usages have also been implemented. Albeit beneficial, several precautions and discussions should be noted in using the risk calculators. The future development of risk calculators for CHB patients can be extended by applying them to additional CHB-related outcomes, and by incorporating emerging risk parameters. 展开更多
关键词 Chronic hepatitis B Hepatocellular carcinoma Risk calculator Hepatitis B virus
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Critical appraisal of novel prediction models and risk calculators for post-hepatectomy liver failure and complications: practicability and generalisability in the real-world setting
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作者 Darren Weiquan Chua Yun Zhao Ye Xin Koh 《Hepatobiliary Surgery and Nutrition》 SCIE 2024年第4期696-698,共3页
Over the last few decades,the evolution of liver resection has progressed through numerous milestones in peri-operative management,operative techniques and novel technologies that have dramatically improved patient sa... Over the last few decades,the evolution of liver resection has progressed through numerous milestones in peri-operative management,operative techniques and novel technologies that have dramatically improved patient safety and outcomes(1).Consequently,such developments have enabled surgeons to embark on liver resections of lesions in technically challenging locations,whereby extended resection or bilovascular reconstruction may be required to ensure oncologic clearance.In the context of extended resections or resection of lesions from heavily diseased livers,concerns remain regarding the adequacy of the remnant future liver remnant(FLR)and liver function,placing patients at risk of the clinical phenomenon known as post-hepatectomy liver failure(PHLF).Although relatively uncommon,PHLF has a reported incidence of up to 32%in the literature and remains an important cause of post-hepatectomy morbidity and mortality(2).Presently,several definitions have been proposed to describe PHLF,the most recent of which was proposed by the International Study Group of Liver Surgery(ISGLS).In this definition,PHLF was defined as an increased international normalized ratio(INR)or hyperbilirubinemia on or after post-operative day 5,with further stratification of severity grades(A,B or C)based on the extent of clinical management(3).While definitions in PHLF assist in providing a common diagnostic framework among physicians,establishing predictors in PHLF is conceivably more helpful as it allows surgeons to have important decision-making details prior to planned liver resection. 展开更多
关键词 HEPATECTOMY post-hepatectomy liver failure(PHLF) predictive model risk calculation
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Risk calculators and updated tools to select and plan a repeat biopsy for prostate cancer detection
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作者 Igor Sorokin Badar M Mian 《Asian Journal of Andrology》 SCIE CAS CSCD 2015年第6期864-869,I0006,共7页
Millions of men each year are faced with a clinical suspicion of prostate cancer (PCa) but the prostate biopsy fails to detect the disease. For the urologists, how to select the appropriate candidate for repeat biop... Millions of men each year are faced with a clinical suspicion of prostate cancer (PCa) but the prostate biopsy fails to detect the disease. For the urologists, how to select the appropriate candidate for repeat biopsy is a significant clinical dilemma. Traditional risk-stratification tools in this setting such as prostate-specific antigen (PSA) related markers and histopathology findings have met with limited correlation with cancer diagnosis or with significant disease. Thus, an individualized approach using predictive models such as an online risk calculator (RC) or updated biomarkers is more suitable in counseling men about their risk of harboring clinically significant prostate cancer, This review will focus on the available risk-stratification tools in the population of men with prior negative biopsies and persistent suspicion of PCa. The underlying methodology and platforms of the available tools are reviewed to better understand the development and validation of these models. The index patient is then assessed with different RCs to determine the range of heterogeneity among various RCs. This should allow the urologists to better incorporate these various risk-stratification tools into their clinical practice and improve patient counseling. 展开更多
关键词 biomarkers prostate cancer repeat biopsy risk calculators
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Stable structures and properties of Ru_(2)Al_(5)
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作者 Jing Luo Meiguang Zhang +1 位作者 Xiaofei Jia Qun Wei 《Chinese Physics B》 2025年第1期414-420,共7页
Novel ordered intermetallic compounds have stimulated much interest.Ru–Al alloys are a prominent class of hightemperature structural materials,but the experimentally reported crystal structure of the intermetallic Ru... Novel ordered intermetallic compounds have stimulated much interest.Ru–Al alloys are a prominent class of hightemperature structural materials,but the experimentally reported crystal structure of the intermetallic Ru_(2)Al_(5) phase remains elusive and debatable.To resolve this controversy,we extensively explored the crystal structures of Ru_(2)Al_(5) using first-principles calculations combined with crystal structure prediction technique.Among the calculated x-ray diffraction patterns and lattice parameters of five candidate Ru2Al5structures,those of the orthorhombic Pmmn structure best aligned with recent experimental results.The structural stabilities of the five Ru_(2)Al_(5)structures were confirmed through formation energy,elastic constants,and phonon spectrum calculations.We also comprehensively analyzed the mechanical and electronic properties of the five candidates.This work can guide the exploration of novel ordered intermetallic compounds in Ru–Al alloys. 展开更多
关键词 crystal structure prediction mechanical properties first-principles calculations
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Risk factors for biometry prediction error by Barrett Universal II intraocular lens formula in Chinese patients
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作者 Xu-Hao Chen Ying Hong +3 位作者 Xiang-Han Ke Si-Jia Song Yu-Jie Cen Chun Zhang 《International Journal of Ophthalmology(English edition)》 2025年第1期74-78,共5页
AIM:To investigate the influence of postoperative intraocular lens(IOL)positions on the accuracy of cataract surgery and examine the predictive factors of postoperative biometry prediction errors using the Barrett Uni... AIM:To investigate the influence of postoperative intraocular lens(IOL)positions on the accuracy of cataract surgery and examine the predictive factors of postoperative biometry prediction errors using the Barrett Universal II(BUII)IOL formula for calculation.METHODS:The prospective study included patients who had undergone cataract surgery performed by a single surgeon from June 2020 to April 2022.The collected data included the best-corrected visual acuity(BCVA),corneal curvature,preoperative and postoperative central anterior chamber depths(ACD),axial length(AXL),IOL power,and refractive error.BUII formula was used to calculate the IOL power.The mean absolute error(MAE)was calculated,and all the participants were divided into two groups accordingly.Independent t-tests were applied to compare the variables between groups.Logistic regression analysis was used to analyze the influence of age,AXL,corneal curvature,and preoperative and postoperative ACD on MAE.RESULTS:A total of 261 patients were enrolled.The 243(93.1%)and 18(6.9%)had postoperative MAE<1 and>1 D,respectively.The number of females was higher in patients with MAE>1 D(χ^(2)=3.833,P=0.039).The postoperative BCVA(logMAR)of patients with MAE>1 D was significantly worse(t=-2.448;P=0.025).After adjusting for gender in the logistic model,the risk of postoperative refractive errors was higher in patients with a shallow postoperative anterior chamber[odds ratio=0.346;95% confidence interval(CI):0.164,0.730,P=0.005].CONCLUSION:Risk factors for biometry prediction error after cataract surgery include the patient’s sex and postoperative ACD.Patients with a shallow postoperative anterior chamber are prone to have refractive errors. 展开更多
关键词 intraocular lens power calculation GENDER anterior chamber depth biometry prediction error
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Phi-based risk calculators performed better in the prediction of prostate cancer in the Chinese population 被引量:7
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作者 Yi-Shuo Wu Xiao-Jian Fu +11 位作者 Rong Na Ding-Wei Ye Jun Qi Xiao-Ling Lin Fang Liu Jian Gong Ning Zhang Guang-Liang Jiang Hao-Wen Jiang Qiang Ding Jianfeng Xu Ying-Hao Sun 《Asian Journal of Andrology》 SCIE CAS CSCD 2019年第6期592-597,共6页
Risk prediction models including the Prostate Health Index(phi)for prostate cancer have been well established and evaluated in the Western population.The aim of this study is to build phi-based risk calculators in a p... Risk prediction models including the Prostate Health Index(phi)for prostate cancer have been well established and evaluated in the Western population.The aim of this study is to build phi-based risk calculators in a prostate biopsy population and evaluate their performanee in predicting prostate cancer(PCa)and high-grade PCa(Gleason score 27)in the Chinese population.We developed risk calculators based on 635 men who underwent initial prostate biopsy.Then,we validated the performance of prostate-specific antigen(PSA),phi,and the risk calculators in an additional observational cohort of 1045 men.We observed that the phi-based risk calculators(risk calculators 2 and 4)outperformed the PSA-based risk calculator for predicting PCa and high-grade PCa in the training cohort.In the validation study,the area under the receiver operating characteristic curve(AUC)for risk calculators 2 and 4 reached 0.91 and 0.92,respectively,for predicting PCa and high-grade PCa,respectively;the AUC values were better than those for risk calculator 1(PSA-based model with an AUC of 0.81 and 0.82,respectively)(all P<0.001).Such superiority was also observed in the stratified population with PSA ranging from 2.0 ng ml^-1 to 10.0 ng ml^-1.Decision curves confirmed that a considerable proportion of unnecessary biopsies could be avoided while applying phi-based risk calculators.In this study,we showed that,compared to risk calculators without phi,phi-based risk calculators exhibited superior discrimination and calibration for PCa in the Chinese biopsy population.Applying these risk calculators also considerably reduced the number of unnecessary biopsies for PCa. 展开更多
关键词 Chinese p2PSA PROSTATE BIOPSY PROSTATE Health Index RISK CALCULATOR
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The Huashan risk calculators performed better in prediction of prostate cancer in Chinese population: a training study followed by a validation study 被引量:7
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作者 Yi-Shuo Wu Ning Zhang +10 位作者 Sheng-Hua Liu Jian-Feng Xu Shi-Jun Tong Ye-Hua Cai Li-Min Zhang Pei-De Bai Meng-Bo HU Hao-Wen Jiang Rong Na Qiang Ding Ying-Hao Sun 《Asian Journal of Andrology》 SCIE CAS CSCD 2016年第6期925-929,共5页
The performances of the Prostate Cancer Prevention Trial (PCPT) risk calculator and other risk calculators for prostate cancer (PCa) prediction in Chinese populations were poorly understood. We performed this stud... The performances of the Prostate Cancer Prevention Trial (PCPT) risk calculator and other risk calculators for prostate cancer (PCa) prediction in Chinese populations were poorly understood. We performed this study to build risk calculators (Huashan risk calculators) based on Chinese population and validated the performance of prostate-specific antigen (PSA), PCPT risk calculator, and Huashan risk calculators in a validation cohort. We built Huashan risk calculators based on data from 1059 men who underwent initial prostate biopsy from January 2006 to December 2010 in a training cohort. Then, we validated the performance of PSA, PCPT risk calculator, and Huashan risk calculators in an observational validation study from January 2011 to December 2014. All necessary clinical information were collected before the biopsy. The results showed that Huashan risk calculators 1 and 2 outperformed the PCPT risk calculator for predicting PCa in both entire training cohort and stratified population (with PSA from 2.0 ng ml^-1 to 20.0 ng ml^-1). In the validation study, Huashan risk calculator 1 still outperformed the PCPT risk calculator in the entire validation cohort (0.849 vs 0.779 in area under the receiver operating characteristic curve [AUC]) and stratified population. A considerable reduction of unnecessary biopsies (approximately 30%) was also observed when the Huashan risk calculators were used. Thus, we believe that the Huashan risk calculators (especially Huashan risk calculator 1) may have added value for predicting PCa in Chinese population. However, these results still needed further evaluation in larger populations. 展开更多
关键词 BIOPSY China prostate cancer prostate-specific antigen risk calculator
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A defective iron-based perovskite cathode for high-performance IT-SOFCs:Tailoring the oxygen vacancies using Nb/Ta co-doping 被引量:3
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作者 Bayu Admasu Beshiwork Xinyu Wan +6 位作者 Min Xu Haoran Guo Birkneh Sirak Teketel Yu Chen Jun Song Chen Tingshuai Li Enrico Traversa 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期306-316,I0008,共12页
The sluggish kinetics of the electrochemical oxygen reduction reaction(ORR)in intermediatetemperature solid oxide fuel cells(IT-SOFCs)greatly limits the overall cell performance.In this study,an efficient and durable ... The sluggish kinetics of the electrochemical oxygen reduction reaction(ORR)in intermediatetemperature solid oxide fuel cells(IT-SOFCs)greatly limits the overall cell performance.In this study,an efficient and durable cathode material for IT-SOFCs is designed based on density functional theory(DFT)calculations by co-doping with Nb and Ta the B-site of the SrFeO_(3-δ)perovskite oxide.The DFT calculations suggest that Nb/Ta co-doping can regulate the energy band of the parent SrFeO_(3-δ)and help electron transfer.In symmetrical cells,such cathode with a SrFe_(0.8)Nb_(0.1)Ta_(0.1)O_(3-δ)(SFNT)detailed formula achieves a low cathode polarization resistance of 0.147Ωcm^(2) at 650℃.Electron spin resonance(ESR)and X-ray photoelectron spectroscopy(XPS)analysis confirm that the co-doping of Nb/Ta in SrFeO_(3-δ)B-site increases the balanced concentration of oxygen vacancies,enhancing the electrochemical performance when compared to 20 mol%Nb single-doped perovskite oxide.The cathode button cell with NiSDC|SDC|SFNT configuration achieves an outstanding peak power density of 1.3 W cm^(-2)at 650℃.Moreover,the button cell shows durability for 110 h under 0.65 V at 600℃ using wet H_(2) as fuel. 展开更多
关键词 Solid oxide fuel cell CATHODE Oxygen reduction reaction Power density DFT calculation
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Tuning interface mechanism of FeCo alloy embedded N,S-codoped carbon substrate for rechargeable Zn-air battery 被引量:2
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作者 Hui Chang Lulu Zhao +4 位作者 Shan Zhao Zong-Lin Liu Peng-Fei Wang Ying Xie Ting-Feng Yi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期400-410,I0010,共12页
The interface mechanism between catalyst and carbon substrate has been the focus of research.In this paper,the FeCo alloy embedded N,S co-doped carbon substrate bifunctional catalyst(FeCo/S-NC)is obtained by a simple ... The interface mechanism between catalyst and carbon substrate has been the focus of research.In this paper,the FeCo alloy embedded N,S co-doped carbon substrate bifunctional catalyst(FeCo/S-NC)is obtained by a simple one-step pyrolysis strategy.The experimental results and density functional theory(DFT)calculation show that the formation of FeCo alloy is conducive to promoting electron transfer,and the introduction of S atom can enhance the interaction between FeCo alloy and carbon substrate,thus inhibiting the migration and agglomeration of particles on the surface of carbon material.The FeCo/SNC catalysts show outstanding performance for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).FeCo/S-NC shows a high half-wave potential(E_(1/2)=0.8823 V)for ORR and a low overpotential at 10 mA cm^(-2)(E_(j=10)=299 mV)for OER.In addition,compared with Pt/C+RuO_(2) assembled Zn-air battery(ZAB),the FeCo/S-NC assembled ZAB exhibits a larger power density(198.8 mW cm^(-2)),a higher specific capacity(786.1 mA h g_(zn)~(-1)),and ultra-stable cycle performance.These results confirm that the optimized composition and the interfacial interaction between catalyst and carbon substrate synergistically enhance the electrochemical performance. 展开更多
关键词 FeCo alloy N S co-doped carbon DFT calculation Zn-air batteries Interfacial interaction
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Prediction of the thermal conductivity of Mg–Al–La alloys by CALPHAD method 被引量:2
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作者 Hongxia Li Wenjun Xu +5 位作者 Yufei Zhang Shenglan Yang Lijun Zhang Bin Liu Qun Luo Qian Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期129-137,共9页
Mg-Al alloys have excellent strength and ductility but relatively low thermal conductivity due to Al addition.The accurate prediction of thermal conductivity is a prerequisite for designing Mg-Al alloys with high ther... Mg-Al alloys have excellent strength and ductility but relatively low thermal conductivity due to Al addition.The accurate prediction of thermal conductivity is a prerequisite for designing Mg-Al alloys with high thermal conductivity.Thus,databases for predicting temperature-and composition-dependent thermal conductivities must be established.In this study,Mg-Al-La alloys with different contents of Al2La,Al3La,and Al11La3phases and solid solubility of Al in the α-Mg phase were designed.The influence of the second phase(s) and Al solid solubility on thermal conductivity was investigated.Experimental results revealed a second phase transformation from Al_(2)La to Al_(3)La and further to Al_(11)La_(3)with the increasing Al content at a constant La amount.The degree of the negative effect of the second phase(s) on thermal diffusivity followed the sequence of Al2La>Al3La>Al_(11)La_(3).Compared with the second phase,an increase in the solid solubility of Al in α-Mg remarkably reduced the thermal conductivity.On the basis of the experimental data,a database of the reciprocal thermal diffusivity of the Mg-Al-La system was established by calculation of the phase diagram (CALPHAD)method.With a standard error of±1.2 W/(m·K),the predicted results were in good agreement with the experimental data.The established database can be used to design Mg-Al alloys with high thermal conductivity and provide valuable guidance for expanding their application prospects. 展开更多
关键词 magnesium alloy thermal conductivity thermodynamic calculations materials computation
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Dual-single-atoms of Pt-Co boost sulfur redox kinetics for ultrafast Li-S batteries 被引量:2
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作者 Hanyan Wu Xuejie Gao +7 位作者 Xinyang Chen Weihan Li Junjie Li Lei Zhang Yang Zhao Ming Jiang Runcang Sun Xueliang Sun 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期53-63,共11页
Applications of lithium-sulfur(Li-S)batteries are still limited by the sluggish conversion kinetics from polysulfide to Li_(2)S.Although various single-atom catalysts are available for improving the conversion kinetic... Applications of lithium-sulfur(Li-S)batteries are still limited by the sluggish conversion kinetics from polysulfide to Li_(2)S.Although various single-atom catalysts are available for improving the conversion kinetics,the sulfur redox kinetics for Li-S batteries is still not ultrafast.Herein,in this work,a catalyst with dual-single-atom Pt-Co embedded in N-doped carbon nanotubes(Pt&Co@NCNT)was proposed by the atomic layer deposition method to suppress the shuttle effect and synergistically improve the interconversion kinetics from polysulfides to Li_(2)S.The X-ray absorption near edge curves indicated the reversible conversion of Li_(2)Sx on the S/Pt&Co@NCNT electrode.Meanwhile,density functional theory demonstrated that the Pt&Co@NCNT promoted the free energy of the phase transition of sulfur species and reduced the oxidative decomposition energy of Li_(2)S.As a result,the batteries assembled with S/Pt&Co@NCNT electrodes exhibited a high capacity retention of 80%at 100 cycles at a current density of 1.3 mA cm^(−2)(S loading:2.5 mg cm^(−2)).More importantly,an excellent rate performance was achieved with a high capacity of 822.1 mAh g^(−1) at a high current density of 12.7 mA cm^(−2).This work opens a new direction to boost the sulfur redox kinetics for ultrafast Li-S batteries. 展开更多
关键词 DFT calculation dual-single-atoms of Pt-Co fast Li-sulfur batteries sulfur redox kinetics XANES analysis
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Composition Engineering Opens an Avenue Toward Efficient and Sustainable Nitrogen Fixation 被引量:2
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作者 Xiaolin Wang Liming Yang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期313-325,共13页
In this work,we open an avenue toward rational design of potential efficient catalysts for sustainable ammonia synthesis through composition engineering strategy by exploiting the synergistic effects among the active ... In this work,we open an avenue toward rational design of potential efficient catalysts for sustainable ammonia synthesis through composition engineering strategy by exploiting the synergistic effects among the active sites as exemplified by diatomic metals anchored graphdiyne via the combination of hierarchical high-throughput screening,first-principles calculations,and molecular dynamics simulations.Totally 43 highly efficient catalysts feature ultralow onset potentials(|U_(onset)|≤0.40 V)with Rh-Hf and Rh-Ta showing negligible onset potentials of 0 and-0.04 V,respectively.Extremely high catalytic activities of Rh-Hf and Rh-Ta can be ascribed to the synergistic effects.When forming heteronuclears,the combinations of relatively weak(such as Rh)and relatively strong(such as Hf or Ta)components usually lead to the optimal strengths of adsorption Gibbs free energies of reaction intermediates.The origin can be ascribed to the mediate d-band centers of Rh-Hf and Rh-Ta,which lead to the optimal adsorption strengths of intermediates,thereby bringing the high catalytic activities.Our work provides a new and general strategy toward the architecture of highly efficient catalysts not only for electrocatalytic nitrogen reduction reaction(eNRR)but also for other important reactions.We expect that our work will boost both experimental and theoretical efforts in this direction. 展开更多
关键词 composition engineering strategy diatomic catalysts electrocatalytic nitrogen reduction reaction first-principles calculations graphdiyne hierarchical high-throughput screening synergistic effects
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Exploring the mechanism of a novel cationic surfactant in bastnaesite flotation via the integration of DFT calculations,in-situ AFM and electrochemistry 被引量:1
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作者 Chang Liu Longhua Xu +7 位作者 Jiushuai Deng Zhiguo Han Yi Li Jiahui Wu Jia Tian Donghui Wang Kai Xue Jinmei Fang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第10期1475-1484,共10页
Effectively separating bastnaesite from calcium-bearing gangue minerals(particularly calcite)presents a formidable challenge,making the development of efficient collectors crucial.To achieve this,we have designed and ... Effectively separating bastnaesite from calcium-bearing gangue minerals(particularly calcite)presents a formidable challenge,making the development of efficient collectors crucial.To achieve this,we have designed and synthesized a novel,highly efficient,water-soluble cationic collector,N-dodecylisopropanolamine(NDIA),for use in the bastnaesite-calcite flotation process.Density functional theory(DFT)calculations identified the amine nitrogen atom in NDIA as the site most susceptible to electrophilic attack and electron loss.By introducing an OH group into the traditional collector dodecylamine(DDA)structure,NDIA provided additional adsorption sites,enabling synergistic adsorption on the surface of bastnaesite,thereby significantly enhancing both the floatability and selectivity of these minerals.The recovery of bastnaesite was 76.02%,while the calcite was 1.26%.The NDIA markedly affected the zeta potential of bastnaesite,while its impact on calcite was relatively minor.Detailed Fourier-transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS)results elucidated that the―NH―and―OH groups in NDIA anchored onto the bastnaesite surface through robust electrostatic and hydrogen bonding interactions,thereby enhancing bastnaesite's affinity for NDIA.Furthermore,in situ atomic force microscopy(AFM)provided conclusive evidence of NDIA aggregation on the bastnaesite surface,improving contact angle and hydrophobicity,and significantly boosting the flotation recovery of bastnaesite. 展开更多
关键词 Novel cationic surfactant DFT calculation BASTNAESITE ELECTROCHEMISTRY In-situ AFM
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Active MoS_(2)-based electrode for green ammonia synthesis 被引量:1
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作者 Xin Liu Lei Yang +2 位作者 Tao Wei Shanping Liu Beibei Xiao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期268-275,共8页
Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia synthesis.One critical aspect to unlocking this technology i... Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia synthesis.One critical aspect to unlocking this technology is to discover the catalysts with high selectivity and efficiency.In this work,the N_(2)-to-NH_(3)conversion on the functional MoS_(2)is fully investigated by density functional theory calculations since the layered MoS_(2)provides the ideal platform for the elaborating copies of the nitrogenase found in nature,wherein the functionalization is achieved via basal-adsorption,basal-substitution or edge-substitution of transition metal elements.Our results reveal that the edge-functionalization is a feasible strategy for the activity promotion;however,the basal-adsorption and basal-substitution separately suffer from the electrochemical instability and the NRR inefficiency.Specifically,MoS_(2)functionalized via edge W-substitution exhibits an exceptional activity.The energetically favored reaction pathway is through the distal pathway and a limiting potential is less than 0.20 V.Overall,this work escalates the rational design of the high-effective catalysts for nitrogen fixation and provides the explanation why the predicated catalyst have a good performance,paving the guidance for the experiments. 展开更多
关键词 Nitrogen reduction reaction Density functional theory calculations Molybdenum disulfide ELECTROCHEMISTRY CATALYST THERMODYNAMICS
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Transformation of long-period stacking ordered structures in Mg-Gd-Y-Zn alloys upon synergistic characterization of first-principles calculation and experiment and its effects on mechanical properties 被引量:1
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作者 Mingyu Li Guangzong Zhang +4 位作者 Siqi Yin Changfeng Wang Ying Fu Chenyang Gu Renguo Guan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第5期1867-1879,共13页
Based on experiments and first-principles calculations,the microstructures and mechanical properties of as-cast and solution treated Mg-10Gd-4Y-xZn-0.6Zr(x=0,1,2,wt.%)alloys are investigated.The transformation process... Based on experiments and first-principles calculations,the microstructures and mechanical properties of as-cast and solution treated Mg-10Gd-4Y-xZn-0.6Zr(x=0,1,2,wt.%)alloys are investigated.The transformation process of long-period stacking ordered(LPSO)structure during solidification and heat treatment and its effect on the mechanical properties of experimental alloys are discussed.Results reveal that the stacking faults and 18R LPSO phases appear in the as-cast Mg-10Gd-4Y-1Zn-0.6Zr and Mg-10Gd-4Y-2Zn-0.6Zr alloys,respectively.After solution treatment,the stacking faults and 18R LPSO phase transform into 14H LPSO phase.The Enthalpies of formation and reaction energy of 14H and 18R LPSO are calculated based on first-principles.Results show that the alloying ability of 18R is stronger than that of 14H.The reaction energies show that the 14H LPSO phase is more stable than the 18R LPSO.The elastic properties of the 14H and 18R LPSO phases are also evaluated by first-principles calculations,and the results are in good agreement with the experimental results.The precipitation of LPSO phase improves the tensile strength,yield strength and elongation of the alloy.After solution treatment,the Mg-10Gd-4Y-2Zn-0.6Zr alloy has the best mechanical properties,and its ultimate tensile strength and yield strength are 278.7 MPa and 196.4 MPa,respectively.The elongation of Mg-10Gd-4Y-2Zn-0.6Zr reaches 15.1,which is higher than that of Mg-10Gd-4Y0.6Zr alloy.The improving mechanism of elastic modulus by the LPSO phases and the influence on the alloy mechanical properties are also analyzed. 展开更多
关键词 Mg-Gd-Y-Zn alloys Long-period stacking ordered First-principles calculations ENTHALPIES Mechanical properties
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Adsorption behaviors and mechanisms of gold recovery from thiosulfate solution by ion exchange resin 被引量:1
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作者 Zhong-lin DONG Tao JIANG +2 位作者 Bin XU Qian LI Yong-bin YANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3372-3385,共14页
The adsorption behaviors and mechanisms of gold from thiosulfate solution on strong-base anion exchange resin were systematically investigated.The comparison experiment of adsorption ability and selectivity for gold s... The adsorption behaviors and mechanisms of gold from thiosulfate solution on strong-base anion exchange resin were systematically investigated.The comparison experiment of adsorption ability and selectivity for gold showed that gel Amberlite IRA-400 resin with Type Ⅰ quaternary ammonium functional group had better adsorption performance.The increases of resin dosage,ammonia concentration and solution pH were favorable to gold adsorption,whereas the rises of cupric and thiosulfate concentrations were disadvantageous to gold loading.Microscopic characterization results indicated that gold was adsorbed in the form of [Au(S_(2)O_(3))_(2)]^(3–) complex anion by exchanging with the counter ion Cl^(–) in the functional group of the resin.Density functional theory calculation result manifested that gold adsorption was mainly depended on the hydrogen bond and van der Waals force generated between O atom in [Au(S_(2)O_(3))_(2)]^(3–) and H atom in the quaternary ammonium functional group of the resin. 展开更多
关键词 GOLD thiosulfate solution resin adsorption behaviors and mechanisms density functional theory calculation
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Effect of cognitive training on brain dynamics 被引量:1
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作者 吕贵阳 徐天勇 +3 位作者 陈飞燕 朱萍 王淼 何国光 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期529-536,共8页
The human brain is highly plastic.Cognitive training is usually used to modify functional connectivity of brain networks.Moreover,the structures of brain networks may determine its dynamic behavior which is related to... The human brain is highly plastic.Cognitive training is usually used to modify functional connectivity of brain networks.Moreover,the structures of brain networks may determine its dynamic behavior which is related to human cognitive abilities.To study the effect of functional connectivity on the brain dynamics,the dynamic model based on functional connections of the brain and the Hindmarsh–Rose model is utilized in this work.The resting-state fMRI data from the experimental group undergoing abacus-based mental calculation(AMC)training and from the control group are used to construct the functional brain networks.The dynamic behavior of brain at the resting and task states for the AMC group and the control group are simulated with the above-mentioned dynamic model.In the resting state,there are the differences of brain activation between the AMC group and the control group,and more brain regions are inspired in the AMC group.A stimulus with sinusoidal signals to brain networks is introduced to simulate the brain dynamics in the task states.The dynamic characteristics are extracted by the excitation rates,the response intensities and the state distributions.The change in the functional connectivity of brain networks with the AMC training would in turn improve the brain response to external stimulus,and make the brain more efficient in processing tasks. 展开更多
关键词 brian dynamics functional brain networks cognitive training abacus-based mental calculation
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p-d Orbital Hybridization Engineered Single-Atom Catalyst for Electrocatalytic Ammonia Synthesis 被引量:1
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作者 Jingkun Yu Xue Yong Siyu Lu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期119-125,共7页
The rational design of metal single-atom catalysts(SACs)for electrochemical nitrogen reduction reaction(NRR)is challenging.Two-dimensional metal-organic frameworks(2DMOFs)is a unique class of promising SACs.Up to now,... The rational design of metal single-atom catalysts(SACs)for electrochemical nitrogen reduction reaction(NRR)is challenging.Two-dimensional metal-organic frameworks(2DMOFs)is a unique class of promising SACs.Up to now,the roles of individual metals,coordination atoms,and their synergy effect on the electroanalytic performance remain unclear.Therefore,in this work,a series of 2DMOFs with different metals and coordinating atoms are systematically investigated as electrocatalysts for ammonia synthesis using density functional theory calculations.For a specific metal,a proper metal-intermediate atoms p-d orbital hybridization interaction strength is found to be a key indicator for their NRR catalytic activities.The hybridization interaction strength can be quantitatively described with the p-/d-band center energy difference(Δd-p),which is found to be a sufficient descriptor for both the p-d hybridization strength and the NRR performance.The maximum free energy change(ΔG_(max))andΔd-p have a volcanic relationship with OsC_(4)(Se)_(4)located at the apex of the volcanic curve,showing the best NRR performance.The asymmetrical coordination environment could regulate the band structure subtly in terms of band overlap and positions.This work may shed new light on the application of orbital engineering in electrocatalytic NRR activity and especially promotes the rational design for SACs. 展开更多
关键词 first-principle calculations Nitrogen reduction p-d orbital hybridization single-atom catalysts
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Boosting oxygen reduction activity and CO_(2) resistance on bismuth ferrite-based perovskite cathode for low-temperature solid oxide fuel cells below 600℃ 被引量:1
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作者 Juntao Gao Zhiyun Wei +5 位作者 Mengke Yuan Zhe Wang Zhe Lü Qiang Li Lingling Xu Bo Wei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期600-609,I0013,共11页
Developing efficient and stable cathodes for low-temperature solid oxide fuel cells(LT-SOFCs) is of great importance for the practical commercialization.Herein,we propose a series of Sm-modified Bi_(0.7-x)Sm_xSr_(0.3)... Developing efficient and stable cathodes for low-temperature solid oxide fuel cells(LT-SOFCs) is of great importance for the practical commercialization.Herein,we propose a series of Sm-modified Bi_(0.7-x)Sm_xSr_(0.3)FeO_(3-δ) perovskites as highly-active catalysts for LT-SOFCs.Sm doping can significantly enhance the electrocata lytic activity and chemical stability of cathode.At 600℃,Bi_(0.675)Sm_(0.025)Sr_(0.3)FeO_(3-δ)(BSSF25) cathode has been found to be the optimum composition with a polarization resistance of 0.098 Ω cm^2,which is only around 22.8% of Bi_(0.7)Sr_(0.3)FeO_(3-δ)(BSF).A full cell utilizing BSSF25 displays an exceptional output density of 790 mW cm^(-2),which can operate continuously over100 h without obvious degradation.The remarkable electrochemical performance observed can be attributed to the improved O_(2) transport kinetics,superior surface oxygen adsorption capacity,as well as O_(2)p band centers in close proximity to the Fermi level.Moreover,larger average bonding energy(ABE) and the presence of highly acidic Bi,Sm,and Fe ions restrict the adsorption of CO_(2) on the cathode surface,resulting in excellent CO_(2) resistivity.This work provides valuable guidance for systematic design of efficient and durable catalysts for LT-SOFCs. 展开更多
关键词 Low-temperature solid oxide fuel cell Perovskite cathode DFT calculations CO_(2) tolerance
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