To address the issue of increased electromagnetic vibration in permanent magnet(PM) motors for electric vehicles under flux-weakening speed extension operation, this paper proposes a low-vibration design method for PM...To address the issue of increased electromagnetic vibration in permanent magnet(PM) motors for electric vehicles under flux-weakening speed extension operation, this paper proposes a low-vibration design method for PM motors from the perspective of saliency ratio. First, by establishing a theoretical model for vibration analysis under flux-weakening operation, it reveals the vibration mechanism whereby high-order armature magnetomotive force(ARM-MMF) harmonics under fluxweakening operation leads to enhanced radial electromagnetic force(REF). Second, an in-depth investigation into the intrinsic relationship between saliency ratio and ARM-MMF is conducted. This study proposes a novel methodology to design key ARM-MMF harmonics that induce significant electromagnetic vibration from the perspective of the saliency ratio. An innovative rotor topology featuring elliptical-arc composite flux barriers is developed to implement this approach. Furthermore, and synergistic optimization is performed with the saliency ratio and torque as optimization objectives to balance vibration suppression and torque output performance. Finally, a prototype is manufactured and tested. Both theoretical and experimental analyses validated the effectiveness of the motor and the proposed design method.展开更多
Brake friction materials with different zinc powder contents(0,2,4,6,8 wt.%)were fabricated via powder metallurgy method.The results indicate that with the increasing zinc powder content,the density and thermal conduc...Brake friction materials with different zinc powder contents(0,2,4,6,8 wt.%)were fabricated via powder metallurgy method.The results indicate that with the increasing zinc powder content,the density and thermal conductivity of the materials gradually increase,while the hardness decreases monotonously.With increasing zinc powder content,the curve of the nominal friction coefficient shows fluctuating trend but the lowest friction coefficient also shows an increase.However,the wear rate and braking noise of the friction material monotonously decrease with increasing zinc content.This effect may be attributed to the transformation of the tribological mechanism from adhesive wear and abrasive wear to adhesive wear.The brake friction material with 4 wt.%zinc powder exhibits both the best tribological and noise performance.展开更多
This paper reviews China’s future fossil fuel supply from the perspectives of physical output and net energy output. Comprehensive analyses of physical output of fossil fuels suggest that China’s total oil productio...This paper reviews China’s future fossil fuel supply from the perspectives of physical output and net energy output. Comprehensive analyses of physical output of fossil fuels suggest that China’s total oil production will likely reach its peak, at about 230 Mt/year(or 9.6 EJ/year),in 2018; its total gas production will peak at around350 Bcm/year(or 13.6 EJ/year) in 2040, while coal production will peak at about 4400 Mt/year(or 91.9 EJ/year)around 2020 or so. In terms of the forecast production of these fuels, there are significant differences among current studies. These differences can be mainly explained by different ultimately recoverable resources assumptions, the nature of the models used, and differences in the historical production data. Due to the future constraints on fossil fuels production, a large gap is projected to grow between domestic supply and demand, which will need to be met by increasing imports. Net energy analyses show that both coal and oil and gas production show a steady declining trend of EROI(energy return on investment) due to the depletion of shallow-buried coal resources and conventional oil and gas resources, which is generally consistent with the approaching peaks of physical production of fossil fuels. The peaks of fossil fuels production, coupled with the decline in EROI ratios, are likely to challenge the sustainable development of Chinese society unless new abundant energy resources with high EROI values can be found.展开更多
The carbon chain cations, HC2nO+(n=3-6) are produced via a pulsed laser vaporization supersonic expansion ion source in the gas phase. Their infrared spectra are measured via mass-selected infrared photodissociation s...The carbon chain cations, HC2nO+(n=3-6) are produced via a pulsed laser vaporization supersonic expansion ion source in the gas phase. Their infrared spectra are measured via mass-selected infrared photodissociation spectroscopy of the CO “tagged”[HC2nO·CO]+ cation complexes in 1600-3500 cm-1 frequency range. The geometric and electronic structures of the [HC2nO·CO]+ complexes and the core HC2nO+(n=3-6) cations are determined with the aid of density functional theory calculations. These HC2nO+(n=3-6) ions are identified to be linear carbon chain derivatives terminally capped by hydrogen and oxygen. The triplet ground states are 10-15 kcal/mol lower in energy than the singlet states, indicating cumulene-like carbon chain structures.展开更多
The peritoneum is the most common site of recurrence of gastric cancer(GC).Early occult peritoneal metastasis is difficult to detect by imaging examination.Stratifying the risk of peritoneal metastasis in patients wit...The peritoneum is the most common site of recurrence of gastric cancer(GC).Early occult peritoneal metastasis is difficult to detect by imaging examination.Stratifying the risk of peritoneal metastasis in patients with different Lauren subtypes is of great clinical value.We performed a univariate Cox regression to identify those genes with prognostic value of overall survival(OS)and peritoneal-specified disease-free survival(psDFS)from the Gene Expression Omnibus database.The candidate genes were screened by the Subpopulation Treatment Effect Pattern Plot(STEPP)method.Propensity score matching(PSM)analysis was used to reduce the interference of confounders on the results.Based on the optimal cut-off values determined by the STEPP method,we found overexpression of three genes(HAND2-AS1,PRKAA2,and VLDLR)was correlated with shorter 1-year psDFS among patients with diffuse-type than that of patients with intestinal-type GC,and it is highly significant.Gene Set Enrichment Analysis(GSEA)potentially suggested that the three genes promote the early occurrence of peritoneal metastasis in patients with diffuse-type GC through glucose metabolism-related pathways.These three genes may be potential biomarkers.They can be used to assess the risk of peritoneal metastases to guide treatment decisions and follow-up strategies.展开更多
Comparing with lithofacies palaeogeography of several great plains,the authors analyzed four great plains in Quaternary diastrophism,the sedimentary facies,sedimentary environment and their evolution from the independ...Comparing with lithofacies palaeogeography of several great plains,the authors analyzed four great plains in Quaternary diastrophism,the sedimentary facies,sedimentary environment and their evolution from the independent embryonic and river system of ancient Heilongjiang finally to the Halar highland,Songnen Plain,Sanjiang Plain,the Xingkai Lake Plain and various river systems,collected the unification outside the system of Heilongjiang River to release into the sea,south ancient Xialiao River finally piracy Dongliao River,Xialiao River had released into the sea the ancient water law vicissitude and the evolved rule.展开更多
Background Acute ischaemic stroke,due to its high mortality and disability rates,imposes a significant economic and social burden worldwide.Typically,endovascular treatment within the therapeutic window is provided to...Background Acute ischaemic stroke,due to its high mortality and disability rates,imposes a significant economic and social burden worldwide.Typically,endovascular treatment within the therapeutic window is provided to salvage the ischaemic penumbra;however,even when recanalisation is successful during endovascular treatment,the clinical outcomes may still be disappointing.This highlights the necessity of further research,so as to discover better solutions to futile recanalisation and improve patient outcomes.Objective To investigate the efficacy and safety of Y-6 sublingual tablets(cilostazol and dexborneol)compared with a placebo in the treatment of patients with acute ischaemic stroke caused by large vessel occlusion.Method The efficacy and safety of Y-6 sublingual tablets in patients with acute ischaemic stroke are evaluated in a phase Ⅱ,randomised,double-blind,double-dummy,placebo-controlled,parallel clinical trial.Eligible patients having provided informed consent are randomised into five groups for a 28-day treatment period.The primary outcome is the percentage of patients achieving the modified Rankin Scale score of 0-1 at 90 days.Discussion The EFfects of Y-6 SUblingual Tablets for PaTients with AcUte Ischemic StRokE trial assesses whether Y-6 sublingual tablets are effective and safe in improving the clinical outcomes of patients with acute ischaemic stroke caused by large vessel occlusion.展开更多
Background Perforating artery territorial infarction(PAI)caused by branch atheromatous disease(BAD)is prone to recurrence and early progression without an effective and well-documented antiplatelet treatment regimen.T...Background Perforating artery territorial infarction(PAI)caused by branch atheromatous disease(BAD)is prone to recurrence and early progression without an effective and well-documented antiplatelet treatment regimen.Tirofiban,an adjunctive antiplatelet agent,has shown great potential to treat acute ischaemic stroke.However,whether the combination of tirofiban and aspirin can improve the prognosis of PAI remains unclear.Aim To explore an effective and safe antiplatelet regimen for reducing the risk of recurrence and early neurological deterioration(END)in PAI caused by BAD by comparing the tirofiban and aspirin combination with placebo and aspirin combination.Methods Tirofiban combined with Aspirin in the Treatment of Acute Penetrating Artery Territory Infarction(STRATEGY)trial is an ongoing multicentre,randomised,placebo-controlled trial in China.Eligible patients shall be randomly assigned to receive standard aspirin with tirofiban or placebo on the first day and standard aspirin from days 2 to 90.The primary endpoint is a new stroke or END within 90 days.The primary safety endpoint is severe or moderate bleeding within 90 days.Discussion The STRATEGY trial will assess whether tirofiban combined with aspirin is effective and safe in preventing recurrence and END in patients with PAI.Trial registration number NCT05310968.展开更多
Background Inflammation and blood-brain barrier disruption may contribute to the pathogenesis of ischaemic stroke.Minocycline was shown to exert anti-inflammatory effects by attenuating microglial activation and prote...Background Inflammation and blood-brain barrier disruption may contribute to the pathogenesis of ischaemic stroke.Minocycline was shown to exert anti-inflammatory effects by attenuating microglial activation and protecting blood-brain barrier in preclinical studies.Previous small-scale clinical studies have suggested that minocycline may have a potential beneficial effect on prognosis in acute ischaemic stroke.However,the efficacy and safety of minocycline in patients with acute ischaemic stroke need to be further confirmed.Study aims We designed the study,Efficacy and Safety of Minocycline in Patients with Moderate to Severe Acute Ischaemic Stroke(EMPHASIS),to evaluate the effect of minocycline in improving the functional outcome and the drug safety in patients with acute ischaemic stroke.Methods The EMPHASIS study is a multicentre,randomised,double-blind,placebo-controlled trial aiming to recruit patients with acute ischaemic stroke.Patients who had ischaemic stroke within 72 hours of onset,a National Institutes of Health Stroke Scale score between 4 and 25 and Ia≤1(moderate-to severe)will be randomly allocated to either minocycline or placebo groups in a 1:1 ratio.Patients will receive minocycline(or placebo)with a loading dose of 200 mg,and subsequent 100 mg every 12 hours for 4 days.All patients will receive routine guideline-based treatment.The primary efficacy outcome is an excellent functional outcome assessed by the proportion of modified Rankin Scale score of 0-1 at 90±7 days.The main safety outcomes include the number of symptomatic intracranial haemorrhage at 24±2 hours and 6±1 days.Discussion The EMPHASIS trial is the first phase III trial to investigate whether minocycline is effective and safe in improving functional outcome at 90 days in patients with moderate-to severe acute ischaemic stroke.The data generated may provide valuable evidence of a potential anti-inflammation treatment for ischaemic stroke.展开更多
基金supported in part by the Modern Agriculture Major Core Technology Innovation Project of Jiangsu Province under Grant CX(22)1005in part by the National Natural Science Foundation of China under Grant 52177046in part by the Project of Innovation of Postgraduate of Jiangsu Province under Grant KYCX25_4228。
文摘To address the issue of increased electromagnetic vibration in permanent magnet(PM) motors for electric vehicles under flux-weakening speed extension operation, this paper proposes a low-vibration design method for PM motors from the perspective of saliency ratio. First, by establishing a theoretical model for vibration analysis under flux-weakening operation, it reveals the vibration mechanism whereby high-order armature magnetomotive force(ARM-MMF) harmonics under fluxweakening operation leads to enhanced radial electromagnetic force(REF). Second, an in-depth investigation into the intrinsic relationship between saliency ratio and ARM-MMF is conducted. This study proposes a novel methodology to design key ARM-MMF harmonics that induce significant electromagnetic vibration from the perspective of the saliency ratio. An innovative rotor topology featuring elliptical-arc composite flux barriers is developed to implement this approach. Furthermore, and synergistic optimization is performed with the saliency ratio and torque as optimization objectives to balance vibration suppression and torque output performance. Finally, a prototype is manufactured and tested. Both theoretical and experimental analyses validated the effectiveness of the motor and the proposed design method.
基金Project(2016YFB1100103)supported by the National Key Research and Development Program of ChinaProject(KC1703004)supported by the Science and Technology Planning Project of Changsha City,ChinaProject(2018ZZTS127)supported by the Fundamental Research Funds for the Central Universities of Central South University,China。
文摘Brake friction materials with different zinc powder contents(0,2,4,6,8 wt.%)were fabricated via powder metallurgy method.The results indicate that with the increasing zinc powder content,the density and thermal conductivity of the materials gradually increase,while the hardness decreases monotonously.With increasing zinc powder content,the curve of the nominal friction coefficient shows fluctuating trend but the lowest friction coefficient also shows an increase.However,the wear rate and braking noise of the friction material monotonously decrease with increasing zinc content.This effect may be attributed to the transformation of the tribological mechanism from adhesive wear and abrasive wear to adhesive wear.The brake friction material with 4 wt.%zinc powder exhibits both the best tribological and noise performance.
基金supported by the National Natural Science Foundation of China(Grant Nos.71503264,71373285,71303258)Humanities and Social Sciences Youth Foundation of the Ministry of Education of China(Grant Nos.15YJC630121,13YJC630148)+1 种基金Science Foundation of China University of Petroleum,Beijing(No.2462014YJRC024)the Major Program of the National Social Science Found of China(Grant No.13&ZD159)
文摘This paper reviews China’s future fossil fuel supply from the perspectives of physical output and net energy output. Comprehensive analyses of physical output of fossil fuels suggest that China’s total oil production will likely reach its peak, at about 230 Mt/year(or 9.6 EJ/year),in 2018; its total gas production will peak at around350 Bcm/year(or 13.6 EJ/year) in 2040, while coal production will peak at about 4400 Mt/year(or 91.9 EJ/year)around 2020 or so. In terms of the forecast production of these fuels, there are significant differences among current studies. These differences can be mainly explained by different ultimately recoverable resources assumptions, the nature of the models used, and differences in the historical production data. Due to the future constraints on fossil fuels production, a large gap is projected to grow between domestic supply and demand, which will need to be met by increasing imports. Net energy analyses show that both coal and oil and gas production show a steady declining trend of EROI(energy return on investment) due to the depletion of shallow-buried coal resources and conventional oil and gas resources, which is generally consistent with the approaching peaks of physical production of fossil fuels. The peaks of fossil fuels production, coupled with the decline in EROI ratios, are likely to challenge the sustainable development of Chinese society unless new abundant energy resources with high EROI values can be found.
基金supported by the National Natural Science Foundation of China (No.21688102, No.21433005, and No.21573047)
文摘The carbon chain cations, HC2nO+(n=3-6) are produced via a pulsed laser vaporization supersonic expansion ion source in the gas phase. Their infrared spectra are measured via mass-selected infrared photodissociation spectroscopy of the CO “tagged”[HC2nO·CO]+ cation complexes in 1600-3500 cm-1 frequency range. The geometric and electronic structures of the [HC2nO·CO]+ complexes and the core HC2nO+(n=3-6) cations are determined with the aid of density functional theory calculations. These HC2nO+(n=3-6) ions are identified to be linear carbon chain derivatives terminally capped by hydrogen and oxygen. The triplet ground states are 10-15 kcal/mol lower in energy than the singlet states, indicating cumulene-like carbon chain structures.
基金This research was approved by National Natural Science Foundation of China(No.81972331)National Science and Technology Major Project of the Ministry of Science and Technology of China(No.2017ZX09304025).
文摘The peritoneum is the most common site of recurrence of gastric cancer(GC).Early occult peritoneal metastasis is difficult to detect by imaging examination.Stratifying the risk of peritoneal metastasis in patients with different Lauren subtypes is of great clinical value.We performed a univariate Cox regression to identify those genes with prognostic value of overall survival(OS)and peritoneal-specified disease-free survival(psDFS)from the Gene Expression Omnibus database.The candidate genes were screened by the Subpopulation Treatment Effect Pattern Plot(STEPP)method.Propensity score matching(PSM)analysis was used to reduce the interference of confounders on the results.Based on the optimal cut-off values determined by the STEPP method,we found overexpression of three genes(HAND2-AS1,PRKAA2,and VLDLR)was correlated with shorter 1-year psDFS among patients with diffuse-type than that of patients with intestinal-type GC,and it is highly significant.Gene Set Enrichment Analysis(GSEA)potentially suggested that the three genes promote the early occurrence of peritoneal metastasis in patients with diffuse-type GC through glucose metabolism-related pathways.These three genes may be potential biomarkers.They can be used to assess the risk of peritoneal metastases to guide treatment decisions and follow-up strategies.
文摘Comparing with lithofacies palaeogeography of several great plains,the authors analyzed four great plains in Quaternary diastrophism,the sedimentary facies,sedimentary environment and their evolution from the independent embryonic and river system of ancient Heilongjiang finally to the Halar highland,Songnen Plain,Sanjiang Plain,the Xingkai Lake Plain and various river systems,collected the unification outside the system of Heilongjiang River to release into the sea,south ancient Xialiao River finally piracy Dongliao River,Xialiao River had released into the sea the ancient water law vicissitude and the evolved rule.
基金supported by grants from the National Natural Science Foundation of China(No.82425101)Beijing Municipal Science&Technology Commission(No.Z231100004823036)+8 种基金Capital's Funds for Health Improvement and Research(2022-2-2045)National Key R&D Program of China(2024YFC3044800,2022YFF1501500,2022YFF1501501,2022YFF1501502,2022YFF1501503,2022YFF1501504,2022YFF1501505)Youth Beijing Scholar Program(No.010)Beijing Laboratory of Oral Health(PXM2021_014226_000041)Beijing Talent Project-Class A:Innovation and Development(No.2018A12)National Ten-Thousand Talent Plan"-Leadership of Scientific and Technological InnovationNational Key R&D Program of China(No.2017YFC1307900,2017YFC1307905)Beijing Outstanding Young Scientist Program(No.BJJWZYJH01201910025030)Noncommunicable Chronic Diseases-National Science and Technology Major Project(2023ZD0504800,2023ZD0504801,2023ZD0504802,2023ZD0504803,2023ZD0504804)。
文摘Background Acute ischaemic stroke,due to its high mortality and disability rates,imposes a significant economic and social burden worldwide.Typically,endovascular treatment within the therapeutic window is provided to salvage the ischaemic penumbra;however,even when recanalisation is successful during endovascular treatment,the clinical outcomes may still be disappointing.This highlights the necessity of further research,so as to discover better solutions to futile recanalisation and improve patient outcomes.Objective To investigate the efficacy and safety of Y-6 sublingual tablets(cilostazol and dexborneol)compared with a placebo in the treatment of patients with acute ischaemic stroke caused by large vessel occlusion.Method The efficacy and safety of Y-6 sublingual tablets in patients with acute ischaemic stroke are evaluated in a phase Ⅱ,randomised,double-blind,double-dummy,placebo-controlled,parallel clinical trial.Eligible patients having provided informed consent are randomised into five groups for a 28-day treatment period.The primary outcome is the percentage of patients achieving the modified Rankin Scale score of 0-1 at 90 days.Discussion The EFfects of Y-6 SUblingual Tablets for PaTients with AcUte Ischemic StRokE trial assesses whether Y-6 sublingual tablets are effective and safe in improving the clinical outcomes of patients with acute ischaemic stroke caused by large vessel occlusion.
基金supported by the following grants:The National Natural Science Foundation of China(no.81825007)Beijing Outstanding Young Scientist Program(no.BJJWZYJH01201910025030)+4 种基金Youth Beijing Scholar Program(no.010)Beijing Talent Project-Class A:Innovation and Development(no.2018A12)'National Ten-Thousand Talent Plan'-Leadership of Scientific and Technological InnovationNational Key R&D Program of China(no.2017YFC1307900,2017YFC1307905)Grand Pharmaceutical Group Co has been providing tirofiban and its placebo free of cost and without any limitations.
文摘Background Perforating artery territorial infarction(PAI)caused by branch atheromatous disease(BAD)is prone to recurrence and early progression without an effective and well-documented antiplatelet treatment regimen.Tirofiban,an adjunctive antiplatelet agent,has shown great potential to treat acute ischaemic stroke.However,whether the combination of tirofiban and aspirin can improve the prognosis of PAI remains unclear.Aim To explore an effective and safe antiplatelet regimen for reducing the risk of recurrence and early neurological deterioration(END)in PAI caused by BAD by comparing the tirofiban and aspirin combination with placebo and aspirin combination.Methods Tirofiban combined with Aspirin in the Treatment of Acute Penetrating Artery Territory Infarction(STRATEGY)trial is an ongoing multicentre,randomised,placebo-controlled trial in China.Eligible patients shall be randomly assigned to receive standard aspirin with tirofiban or placebo on the first day and standard aspirin from days 2 to 90.The primary endpoint is a new stroke or END within 90 days.The primary safety endpoint is severe or moderate bleeding within 90 days.Discussion The STRATEGY trial will assess whether tirofiban combined with aspirin is effective and safe in preventing recurrence and END in patients with PAI.Trial registration number NCT05310968.
基金National Natural Science Foundation of China(No.81825007,82271516)Beijing Healthunion Cardio-cerebrovascular Disease Prevention and Treatment Foundation(No.20230418-J E 010).
文摘Background Inflammation and blood-brain barrier disruption may contribute to the pathogenesis of ischaemic stroke.Minocycline was shown to exert anti-inflammatory effects by attenuating microglial activation and protecting blood-brain barrier in preclinical studies.Previous small-scale clinical studies have suggested that minocycline may have a potential beneficial effect on prognosis in acute ischaemic stroke.However,the efficacy and safety of minocycline in patients with acute ischaemic stroke need to be further confirmed.Study aims We designed the study,Efficacy and Safety of Minocycline in Patients with Moderate to Severe Acute Ischaemic Stroke(EMPHASIS),to evaluate the effect of minocycline in improving the functional outcome and the drug safety in patients with acute ischaemic stroke.Methods The EMPHASIS study is a multicentre,randomised,double-blind,placebo-controlled trial aiming to recruit patients with acute ischaemic stroke.Patients who had ischaemic stroke within 72 hours of onset,a National Institutes of Health Stroke Scale score between 4 and 25 and Ia≤1(moderate-to severe)will be randomly allocated to either minocycline or placebo groups in a 1:1 ratio.Patients will receive minocycline(or placebo)with a loading dose of 200 mg,and subsequent 100 mg every 12 hours for 4 days.All patients will receive routine guideline-based treatment.The primary efficacy outcome is an excellent functional outcome assessed by the proportion of modified Rankin Scale score of 0-1 at 90±7 days.The main safety outcomes include the number of symptomatic intracranial haemorrhage at 24±2 hours and 6±1 days.Discussion The EMPHASIS trial is the first phase III trial to investigate whether minocycline is effective and safe in improving functional outcome at 90 days in patients with moderate-to severe acute ischaemic stroke.The data generated may provide valuable evidence of a potential anti-inflammation treatment for ischaemic stroke.
