期刊文献+
共找到4,590篇文章
< 1 2 230 >
每页显示 20 50 100
The Paradigm of the Seismic Zonation Continuality
1
作者 A. S. Aleshin 《World Journal of Engineering and Technology》 2015年第3期338-343,共6页
Basic concepts of seismic zonation in Russia are the degree of intensity and soil categories that correspond to discrete structure in the ratio “seismic impact-ground reaction”. Meanwhile, the parameters of seismic ... Basic concepts of seismic zonation in Russia are the degree of intensity and soil categories that correspond to discrete structure in the ratio “seismic impact-ground reaction”. Meanwhile, the parameters of seismic effects, and the parameters of soil properties are continuous in the space. The report expounds the basic theory, adequately representing the above mentioned continuality. Thus, many the concepts of seismic zonation, used now, become either more correct, or unnecessary. 展开更多
关键词 SEISMIC MICROZONATION Intensity SITE Class REFERENT Soil SEISMIC Impact Response Spectra SITE COEFFICIENT Dynamics COEFFICIENT Model continuality
下载PDF
持续气道正压通气治疗重症阻塞性睡眠呼吸暂停低通气综合征伴黏多糖病患儿1例
2
作者 马薇 范杰 +1 位作者 苏晓艳 谢宇平 《中国耳鼻咽喉头颈外科》 CSCD 2024年第7期474-474,476,共2页
1临床资料患儿,男,6岁,因“睡眠打鼾2年余,加重伴憋气2 d”于2022-09-09就诊于甘肃省人民医院。患儿自幼体格生长和智力发育较同龄儿落后,面容特殊;入院前2年无明显诱因出现鼻塞、睡眠时张口呼吸,打鼾憋气,感冒时鼻塞、打鼾症状尤为明显... 1临床资料患儿,男,6岁,因“睡眠打鼾2年余,加重伴憋气2 d”于2022-09-09就诊于甘肃省人民医院。患儿自幼体格生长和智力发育较同龄儿落后,面容特殊;入院前2年无明显诱因出现鼻塞、睡眠时张口呼吸,打鼾憋气,感冒时鼻塞、打鼾症状尤为明显,有时伴有耳痛。入院前1周患儿感冒后鼻塞加重,近两日夜间睡眠打鼾加重,伴明显憋气,夜间口唇青紫。患儿父母非近亲婚配,其家族中未发现类似情况。查体:身高63 cm,体重22 kg,特殊面容. 展开更多
关键词 粘多糖病 粘多糖累积病(Mucopolysaccharidoses) 睡眠呼吸暂停 阻塞性(Sleep Apnea Obstructive) 持续正压气道压力 连续气道正压通气(Continuous Positive Airway Pressure)
下载PDF
A Discussion on the Flexible Regulation Capacity Requirements of China’s Power System 被引量:1
3
作者 Qiang Zhao Yuqiong Zhang +3 位作者 Xiaoxin Zhou Ziwei Chen Huaguang Yan Honghua Yang 《Engineering》 SCIE EI CAS CSCD 2024年第2期12-16,共5页
A high proportion of variable renewable energy(VRE)is one of the most significant characteristics of China’s future power system under the"dual carbon"target.However,wind and solar power units are more unco... A high proportion of variable renewable energy(VRE)is one of the most significant characteristics of China’s future power system under the"dual carbon"target.However,wind and solar power units are more uncontrollable and less supportive for power system stability than traditional thermal power units,due to their susceptibility to the weather and the grid connection of power electronics.Therefore,as the capacity and generation of VRE grow rapidly and even dominate the power structure,the power system’s ability to deal with disturbances will continue to decrease. 展开更多
关键词 WEATHER CONTINUE SUSCEPTIBILITY
下载PDF
Suppressive effects of exercise-conditioned serum on cancer cells:A narrative review of the influence of exercise mode,volume,and intensity 被引量:1
4
作者 Francesco Bettariga Dennis R.Taaffe +3 位作者 Daniel A.Galvao Chris Bishop Jin-Soo Kim Robert U.Newton 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第4期484-498,F0003,共16页
Cancer is a major cause of morbidity and mortality worldwide,and the incidence is increasing,highlighting the need for effective strategies to treat this disease.Exercise has emerged as fundamental therapeutic medicin... Cancer is a major cause of morbidity and mortality worldwide,and the incidence is increasing,highlighting the need for effective strategies to treat this disease.Exercise has emerged as fundamental therapeutic medicine in the management of cancer,associated with a lower risk of recur-rence and increased survival.Several avenues of research demonstrate reduction in growth,proliferation,and increased apoptosis of cancer cells,including breast,prostate,colorectal,and lung cancer,when cultured by serum collected after exercise in vitro(i.e.,the cultivation of cancer cell lines in an experimental setting,which simplifies the biological system and provides mechanistic insight into cell responses).The underlying mechanisms of exercise-induced cancer suppressive effects may be attributed to the alteration in circulating factors,such as skeletal muscle-induced cytokines(i.e.,myokines)and hormones.However,exercise-induced tumor suppressive effects and detailed information about training interventions are not well investigated,constraining more precise application of exercise medicine within clinical oncology.To date,it remains unclear what role different training modes(i.e.,resistance and aerobic training)as well as volume and intensity have on exercise-condi-tioned serum and its effects on cancer cells.Nevertheless,the available evidence is that a single bout of aerobic training at moderate to vigorous intensity has cancer suppressive effects,while for chronic training interventions,exercise volume appears to be an influential candidate driving cancer inhibitory effects regardless of training mode.Insights for future research investigating training modes,volume and intensity are provided to further our understanding of the effects of exercise-conditioned serum on cancer cells. 展开更多
关键词 Cancer cells High intensity interval training Moderate intensity continuous training Resistance training MYOKINES
下载PDF
Regulatable Orthotropic 3D Hybrid Continuous Carbon Networks for Efficient Bi-Directional Thermal Conduction 被引量:1
5
作者 Huitao Yu Lianqiang Peng +2 位作者 Can Chen Mengmeng Qin Wei Feng 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期136-148,共13页
Vertically oriented carbon structures constructed from low-dimen-sional carbon materials are ideal frameworks for high-performance thermal inter-face materials(TIMs).However,improving the interfacial heat-transfer eff... Vertically oriented carbon structures constructed from low-dimen-sional carbon materials are ideal frameworks for high-performance thermal inter-face materials(TIMs).However,improving the interfacial heat-transfer efficiency of vertically oriented carbon structures is a challenging task.Herein,an orthotropic three-dimensional(3D)hybrid carbon network(VSCG)is fabricated by depositing vertically aligned carbon nanotubes(VACNTs)on the surface of a horizontally oriented graphene film(HOGF).The interfacial interaction between the VACNTs and HOGF is then optimized through an annealing strategy.After regulating the orientation structure of the VACNTs and filling the VSCG with polydimethylsi-loxane(PDMS),VSCG/PDMS composites with excellent 3D thermal conductive properties are obtained.The highest in-plane and through-plane thermal conduc-tivities of the composites are 113.61 and 24.37 W m^(-1)K^(-1),respectively.The high contact area of HOGF and good compressibility of VACNTs imbue the VSCG/PDMS composite with low thermal resistance.In addition,the interfacial heat-transfer efficiency of VSCG/PDMS composite in the TIM performance was improved by 71.3%compared to that of a state-of-the-art thermal pad.This new structural design can potentially realize high-performance TIMs that meet the need for high thermal conductivity and low contact thermal resistance in interfacial heat-transfer processes. 展开更多
关键词 Orthotropic continuous structures Hybrid carbon networks Carbon/polymer composites Thermal interface materials
下载PDF
Traction power systems for electrified railways:evolution,state of the art,and future trends 被引量:1
6
作者 Haitao Hu Yunjiang Liu +4 位作者 Yong Li Zhengyou He Shibin Gao Xiaojuan Zhu Haidong Tao 《Railway Engineering Science》 EI 2024年第1期1-19,共19页
Traction power systems(TPSs)play a vital role in the operation of electrified railways.The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified ... Traction power systems(TPSs)play a vital role in the operation of electrified railways.The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified railways toward high-efficiency and resilience but also an inevitable requirement to achieve carbon neutrality target.On the basis of sorting out the power supply structures of conventional AC and DC modes,this paper first reviews the characteristics of the existing TPSs,such as weak power supply flexibility and low-energy efficiency.Furthermore,the power supply structures of various TPSs for future electrified railways are described in detail,which satisfy longer distance,low-carbon,high-efficiency,high-reliability and high-quality power supply requirements.Meanwhile,the application prospects of different traction modes are discussed from both technical and economic aspects.Eventually,this paper introduces the research progress of mixed-system electrified railways and traction power supply technologies without catenary system,speculates on the future development trends and challenges of TPSs and predicts that TPSs will be based on the continuous power supply mode,employing power electronic equipment and intelligent information technology to construct a railway comprehensive energy system with renewable energy. 展开更多
关键词 Railway traction power system Future electrified railway Flexible continuous power supply Renewable energy Integrated energy system
下载PDF
Application and management of continuous glucose monitoring in diabetic kidney disease 被引量:1
7
作者 Xin-Miao Zhang Quan-Quan Shen 《World Journal of Diabetes》 SCIE 2024年第4期591-597,共7页
Diabetic kidney disease(DKD)is a common complication of diabetes mellitus that contributes to the risk of end-stage kidney disease(ESKD).Wide glycemic var-iations,such as hypoglycemia and hyperglycemia,are broadly fou... Diabetic kidney disease(DKD)is a common complication of diabetes mellitus that contributes to the risk of end-stage kidney disease(ESKD).Wide glycemic var-iations,such as hypoglycemia and hyperglycemia,are broadly found in diabetic patients with DKD and especially ESKD,as a result of impaired renal metabolism.It is essential to monitor glycemia for effective management of DKD.Hemoglobin A1c(HbA1c)has long been considered as the gold standard for monitoring glycemia for>3 months.However,assessment of HbA1c has some bias as it is susceptible to factors such as anemia and liver or kidney dysfunction.Continuous glucose monitoring(CGM)has provided new insights on glycemic assessment and management.CGM directly measures glucose level in interstitial fluid,reports real-time or retrospective glucose concentration,and provides multiple glycemic metrics.It avoids the pitfalls of HbA1c in some contexts,and may serve as a precise alternative to estimation of mean glucose and glycemic variability.Emerging studies have demonstrated the merits of CGM for precise monitoring,which allows fine-tuning of glycemic management in diabetic patients.Therefore,CGM technology has the potential for better glycemic monitoring in DKD patients.More research is needed to explore its application and management in different stages of DKD,including hemodialysis,peritoneal dialysis and kidney transplantation. 展开更多
关键词 Diabetic kidney disease Continuous glucose monitoring Glycemic monitoring HEMODIALYSIS Peritoneal dialysis Kidney transplantation
下载PDF
A 28/56 Gb/s NRZ/PAM-4 dual-mode transceiver with 1/4 rate reconfigurable 4-tap FFE and half-rate slicer in a 28-nm CMOS 被引量:1
8
作者 Yukun He Zhao Yuan +5 位作者 Kanan Wang Renjie Tang Yunxiang He Xian Chen Zhengyang Ye Xiaoyan Gui 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期35-46,共12页
A 28/56 Gb/s NRZ/PAM-4 dual-mode transceiver(TRx)designed in a 28-nm complementary metal-oxide-semiconduc-tor(CMOS)process is presented in this article.A voltage-mode(VM)driver featuring a 4-tap reconfigurable feed-fo... A 28/56 Gb/s NRZ/PAM-4 dual-mode transceiver(TRx)designed in a 28-nm complementary metal-oxide-semiconduc-tor(CMOS)process is presented in this article.A voltage-mode(VM)driver featuring a 4-tap reconfigurable feed-forward equal-izer(FFE)is employed in the quarter-rate transmitter(TX).The half-rate receiver(RX)incorporates a continuous-time linear equal-izer(CTLE),a 3-stage high-speed slicer with multi-clock-phase sampling,and a clock and data recovery(CDR).The experimen-tal results show that the TRx operates at a maximum speed of 56 Gb/s with chip-on board(COB)assembly.The 28 Gb/s NRZ eye diagram shows a far-end vertical eye opening of 210 mV with an output amplitude of 351 mV single-ended and the 56 Gb/s PAM-4 eye diagram exhibits far-end eye opening of 33 mV(upper-eye),31 mV(mid-eye),and 28 mV(lower-eye)with an output amplitude of 353 mV single-ended.The recovered 14 GHz clock from the RX exhibits random jitter(RJ)of 469 fs and deterministic jitter(DJ)of 8.76 ps.The 875 Mb/s de-multiplexed data features 593 ps horizontal eye opening with 32.02 ps RJ,at bit-error rate(BER)of 10-5(0.53 UI).The power dissipation of TX and RX are 125 and 181.4 mW,respectively,from a 0.9-V sup-ply. 展开更多
关键词 transceiver(TRx) feed-forward equalizer(FFE) clock and data recovery(CDR) continuous time linear equalizer(CTLE)
下载PDF
Effect of continuous nursing on treatment compliance and side effect management of coronary heart disease 被引量:1
9
作者 Juan Wei Bai-Wen-Xian Li +2 位作者 Shao-Jie Han Hong-Jie Zhuang Wen-Hong Cao 《World Journal of Clinical Cases》 SCIE 2024年第19期3701-3707,共7页
BACKGROUND There are relatively few studies on continuing care of coronary heart disease(CHD),and its research value needs to be further clarified.AIM To investigate the effect of continuous nursing on treatment compl... BACKGROUND There are relatively few studies on continuing care of coronary heart disease(CHD),and its research value needs to be further clarified.AIM To investigate the effect of continuous nursing on treatment compliance and side effect management in patients with CHD.METHODS This is a retrospective study with patients from January 2021 to 2023.The study was divided into two groups with 30 participants in each group.Self-rating anxiety scale(SAS)and Self-rating depression scale(SDS)were used to assess patients'anxiety and depression,and medical coping questionnaire was used to assess patients'coping styles.The pelvic floor dysfunction questionnaire(PFDI-20)was used to assess the status of pelvic floor function,including bladder symptoms,intestinal symptoms,and pelvic symptoms.RESULTS SAS score decreased from 57.33±3.01before treatment to 41.33±3.42 after treatment,SDS score decreased from 50.40±1.45 to 39.47±1.57.The decrease of these two indexes was statistically significant(P<0.05).PFDI-20 scores decreased from the mean 16.83±1.72 before treatment to 10.47±1.3the mean after treatment,which was statistically significant(P<0.05).CONCLUSION The results of this study indicate that pioneering research in continuous care of CHD has a positive impact on improving patients'treatment compliance,reducing anxiety and depression levels,and improving coping styles and pelvic floor functional status. 展开更多
关键词 Coronary heart disease Continuing care Treatment compliance Anxiety and depression Coping style Pelvic floor function status Pioneering study
下载PDF
Analysis of the Nursing Effect of Continuity of Care on Elderly Patients with Coronary Heart Disease Unstable Angina and its Impact on Quality of Life 被引量:1
10
作者 Ling Yan 《Journal of Clinical and Nursing Research》 2024年第2期185-190,共6页
Objective:To analyze the effect of using continuity of care for elderly patients with coronary heart disease(CHD)with unstable angina pectoris(UAP)and its impact on their quality of life.Methods:100 cases of elderly p... Objective:To analyze the effect of using continuity of care for elderly patients with coronary heart disease(CHD)with unstable angina pectoris(UAP)and its impact on their quality of life.Methods:100 cases of elderly patients with CHD with UAP admitted to our hospital from March 2022 to March 2023 were selected and grouped into an observation group and a control group of 50 cases each according to the randomized number table method.The nursing effect and quality of life of the observation group(continuity nursing)and the control group(routine nursing)were compared.Results:The total effective rate of nursing care was 96.00%observation group and 80.00%for the control group,and the differences were significant(χ2=6.061,P<0.05).Patients in the observation group had fewer episodes(1.42±0.21)times/week and a shorter duration(5.46±0.39)min,which were better than the control group(t=3.465,2.973;P<0.05).The depression self-rating depression scale(SDS)score(42.16±6.64)and anxiety self-rating scale(SAS)score(32.26±7.35)in the observation group were lower and the quality of life was higher as compared to that of the control group(P<0.05).Conclusion:Continuous nursing care improved the nursing effect of elderly CHD with UAP patients,promoted the alleviation of UAP symptoms,improved patient mentality,and improved their quality of life.Hence,continuous nursing care possesses significant clinical application value. 展开更多
关键词 Continuity of care ELDERLY Coronary heart disease Unstable angina Nursing outcomes Quality of life
下载PDF
Epigenetic memory of drug exposure history controls neural stem cell quiescence in the adult brain
11
作者 Masakazu Iwamoto Taito Matsuda 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期711-712,共2页
Neural stem cells(NSCs)are the source of all neurons and glial cells(astrocytes and oligodendrocytes)in the central nervous system.The adult mammalian brain retains NSCs in the subgranular zone of the dentate gyrus in... Neural stem cells(NSCs)are the source of all neurons and glial cells(astrocytes and oligodendrocytes)in the central nervous system.The adult mammalian brain retains NSCs in the subgranular zone of the dentate gyrus in the hippocampus and ventricular subventricular zone lining the lateral ventricle(Olpe and Jessberger,2022).Adult NSCs in rodents are preserved throughout life and continuously produce new neurons that integrate into the pre-existing neuronal network. 展开更多
关键词 NEURAL INTEGRATE continuously
下载PDF
Evaluation of ruminal methane and ammonia formation and microbiota composition as affected by supplements based on mixtures of tannins and essential oils using Rusitec
12
作者 Giulia Foggi Melissa Terranova +9 位作者 Matteo Daghio Sergej L.Amelchanka Giuseppe Conte Simon Ineichen Monica Agnolucci Carlo Viti Alberto Mantino Arianna Buccioni Michael Kreuzer Marcello Mele 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1607-1622,共16页
Background Dietary supplements based on tannin extracts or essential oil compounds(EOC)have been repeatedly reported as a promising feeding strategy to reduce the environmental impact of ruminant husbandry.A previous ... Background Dietary supplements based on tannin extracts or essential oil compounds(EOC)have been repeatedly reported as a promising feeding strategy to reduce the environmental impact of ruminant husbandry.A previous batch culture screening of various supplements identified selected mixtures with an enhanced potential to mitigate ruminal methane and ammonia formation.Among these,Q-2(named after quebracho extract and EOC blend 2,composed of carvacrol,thymol,and eugenol)and C-10(chestnut extract and EOC blend 10,consisting of oregano and thyme essential oils and limonene)have been investigated in detail in the present study with the semi-continuous rumen simulation technique(Rusitec)in three independent runs.For this purpose,Q-2 and C-10,dosed according to the previous study,were compared with a non-supplemented diet(negative control,NC)and with one supplemented with the commercial EOC-based Agolin^(R) Ruminant(positive control,PC).Results From d 5 to 10 of fermentation incubation liquid was collected and analysed for pH,ammonia,protozoa count,and gas composition.Feed residues were collected for the determination of ruminal degradability.On d 10,samples of incubation liquid were also characterised for bacterial,archaeal and fungal communities by high-throughput sequencing of 16S rRNA and 26S ribosomal large subunit gene amplicons.Regardless of the duration of the fermentation period,Q-2 and C-10 were similarly efficient as PC in mitigating either ammonia(-37%by Q-2,-34%by PC)or methane formation(-12%by C-10,-12%by PC).The PC was also responsible for lower feed degradability and bacterial and fungal richness,whereas Q-2 and C-10 effects,particularly on microbiome diversities,were limited compared to NC.Conclusions All additives showed the potential to mitigate methane or ammonia formation,or both,in vitro over a period of 10 d.However,several differences occurred between PC and Q-2/C-10,indicating different mechanisms of action.The pronounced defaunation caused by PC and its suggested consequences apparently determined at least part of the mitigant effects.Although the depressive effect on NDF degradability caused by Q-2 and C-10 might partially explain their mitigation properties,their mechanisms of action remain mostly to be elucidated. 展开更多
关键词 Additive Bacteria Continuous culture DEGRADABILITY Fermentation Fungi Greenhouse gas In vitro Microbiome RUMEN
下载PDF
Evolution and Role of Optimizers in Training Deep Learning Models
13
作者 XiaoHao Wen MengChu Zhou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第10期2039-2042,共4页
TO perform well,deep learning(DL)models have to be trained well.Which optimizer should be adopted?We answer this question by discussing how optimizers have evolved from traditional methods like gradient descent to mor... TO perform well,deep learning(DL)models have to be trained well.Which optimizer should be adopted?We answer this question by discussing how optimizers have evolved from traditional methods like gradient descent to more advanced techniques to address challenges posed by highdimensional and non-convex problem space.Ongoing challenges include their hyperparameter sensitivity,balancing between convergence and generalization performance,and improving interpretability of optimization processes.Researchers continue to seek robust,efficient,and universally applicable optimizers to advance the field of DL across various domains. 展开更多
关键词 WHICH DEEP CONTINUE
下载PDF
Measurement,associations,patterns,and promotion:Unveiling vital areas in physical activity epidemiology
14
作者 Kara M.Whitaker Guest editor Michael J.LaMonte 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第5期605-607,共3页
Physical activity(PA)epidemiology first emerged as a new field of study around the 1950s with publication of seminal investigations on London civil servants1 and has continued to evolve as a scientific discipline to p... Physical activity(PA)epidemiology first emerged as a new field of study around the 1950s with publication of seminal investigations on London civil servants1 and has continued to evolve as a scientific discipline to present time.This subdiscipline of epidemiology studies the frequencies,distributions,and dynamics of PA and its impact on human health,morbidity,and mortality.Research over the past 75 years has demonstrated numerous health benefits of PA.Based on these research findings,the World Health Organization recommends adults aged 18-64 years engage in at least 150-300 min of moderate-intensity aerobic PA per week,or at least 75-150 min of vigorous-intensity aerobic PA per week,or a combination of both intensities. 展开更多
关键词 EPIDEMIOLOGY PROMOTION continued
下载PDF
Transforming agri-food systems for multiple wins in nutrition,inclusion and environment
15
作者 Shenggen Fan Qiran Zhao Jingjing Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期355-358,共4页
The call for agri-food system transformation is urgent in many global development agendas(UN 2023).Food systems have contributed to economic prosperity and feeding the world,but they are also associated with numerous ... The call for agri-food system transformation is urgent in many global development agendas(UN 2023).Food systems have contributed to economic prosperity and feeding the world,but they are also associated with numerous challenges,including climate change,continued hunger,poor diets and malnutrition,and increasing disparities(Webb et al.2020;Fanzo et al.2021). 展开更多
关键词 continued NUTRITION URGENT
下载PDF
Strengthening effect of prefabrication(10-12)tensile twinning on AZ80+0.4%Ce magnesium alloy and inhibition mechanism of discontinuous precipitation
16
作者 Zhen Wang Xi Zhao +5 位作者 Zhimin Zhang Yaojin Wu Kai Chen Xianwei Ren Dengkui Wang Wei Wang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第5期1918-1930,共13页
This paper provided an effective method to further improve the mechanical properties of the AZ80+0.4%Ce magnesium alloy wheel spoke.The effect of high strength and ductility was obtained with a yield strength of 295.3... This paper provided an effective method to further improve the mechanical properties of the AZ80+0.4%Ce magnesium alloy wheel spoke.The effect of high strength and ductility was obtained with a yield strength of 295.36 MPa,an elongation of 10%,by the combination of pre-deformation(7%deformation)and two-stage aging treatment(120℃/9 h+175℃/24 h).The evolution of the microstructure and properties of the alloy was explored under the coupling conditions of different pre-deformation degrees and multi-stage aging.The results show that,pre-deformation introduced a large number of(1012)tensile twinning and dislocations,which greatly promoted the probability of continuous precipitates(CPs)appearing.On the contrary,the discontinuous precipitates(DPs)were limited by the vertical and horizontal twin structure.As a result,the pre-nucleation method of two-stage aging increased the proportion of CPs by 34%-38%.Owing to the DPs was effectively suppressed,the alloy's yield strength has been greatly improved.Besides,under multi-stage aging,the twin boundaries induce protruding nucleation to form static recrystallization by hindering the migration of dislocations,and the matrix swallows the twins,then the texture gradually tilts from the two poles to the basal plane.As an important supplement,the grain refinement and oblique texture promoted the improvement of the yield strength of the component. 展开更多
关键词 Magnesium alloy Pre-deformed Two-stage aging Tensile twinning Continuous precipitates Texture
下载PDF
GLOBAL CONVERGENCE OF A CAUTIOUS PROJECTION BFGS ALGORITHM FOR NONCONVEX PROBLEMS WITHOUT GRADIENT LIPSCHITZ CONTINUITY
17
作者 Gonglin YUAN Xiong ZHAO Jiajia YU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1735-1746,共12页
A cautious projection BFGS method is proposed for solving nonconvex unconstrained optimization problems.The global convergence of this method as well as a stronger general convergence result can be proven without a gr... A cautious projection BFGS method is proposed for solving nonconvex unconstrained optimization problems.The global convergence of this method as well as a stronger general convergence result can be proven without a gradient Lipschitz continuity assumption,which is more in line with the actual problems than the existing modified BFGS methods and the traditional BFGS method.Under some additional conditions,the method presented has a superlinear convergence rate,which can be regarded as an extension and supplement of BFGS-type methods with the projection technique.Finally,the effectiveness and application prospects of the proposed method are verified by numerical experiments. 展开更多
关键词 cautious BFGS nonconvex problems Lipschitz continuity projection technique global convergence
下载PDF
Enhanced measurement precision with continuous interrogation during dynamical decoupling
18
作者 张军 杜鹏 +3 位作者 敬雷 徐鹏 尤力 张文献 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期88-94,共7页
Dynamical decoupling(DD)is normally ineffective when applied to DC measurement.In its straightforward implementation,DD nulls out DC signal as well while suppressing noise.This work proposes a phase relay method that ... Dynamical decoupling(DD)is normally ineffective when applied to DC measurement.In its straightforward implementation,DD nulls out DC signal as well while suppressing noise.This work proposes a phase relay method that is capable of continuously interrogating the DC signal over many DD cycles.We illustrate its efficacy when applied to the measurement of a weak DC magnetic field with an atomic spinor Bose-Einstein condensate.Sensitivities approaching standard quantum limit or Heisenberg limit are potentially realizable for a coherent spin state or a squeezed spin state of 10000 atoms,respectively,while ambient laboratory level noise is suppressed by DD.Our work offers a practical approach to mitigate the limitations of DD to DC measurement and would find other applications for resorting coherence in quantum sensing and quantum information processing research. 展开更多
关键词 quantum sensing continuous interrogation quantum magnetometer dynamical decoupling Heisenberg limit
下载PDF
八步连续流全合成维生素B_(1)工艺研究
19
作者 Meifen Jiang Minjie Liu +2 位作者 Weijian Li Yingqi Xia Fen-Er Chen 《Engineering》 SCIE EI CAS CSCD 2024年第1期226-232,共7页
Vitamin B_(1) is widely applied in the healthcare and food industry as an antineuritic and antioxidant to maintain the normal functioning of nerve conduction,the heart,and the gastrointestinal tract.This study reports... Vitamin B_(1) is widely applied in the healthcare and food industry as an antineuritic and antioxidant to maintain the normal functioning of nerve conduction,the heart,and the gastrointestinal tract.This study reports on an integrated eight-step continuous-flow synthesis of vitamin B_(1) from commercially available 2-cyanoacetamide.The proposed continuous-flow process is based on advances in chemistry,engineering,and equipment design,and affords improved performance and safety compared with batch-mode manufacturing.Several challenges were precisely investigated and controlled,including mixing,unexpected clogging,solvent switches,an exothermic reaction,and the prevention of side reactions,using various micro-channel flow reactors,mixers,separators,and continuous filters.Vitamin B_(1) was produced with a separated yield of 47.7% and high purity,with a total residence time of about 3.5 h.This eight-step continuous-flow protocol enables technology involving up to six of the key principles of green chemistry.Hence,the application of flow technology is of paramount importance for improving security,reducing waste,and,in particular,improving the efficiency of batch operations that require several days for manufacturing. 展开更多
关键词 Vitamin B_(1) Continuous-flow synthesis MICRO-REACTOR Continuous manufacturing
下载PDF
Irregular initial solidification by mold thermal monitoring in the continuous casting of steels:A review
20
作者 Qiuping Li Guanghua Wen +3 位作者 Fuhang Chen Ping Tang Zibing Hou Xinyun Mo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期1003-1015,共13页
Occasional irregular initial solidification phenomena,including stickers,deep oscillation marks,depressions,and surface cracks of strand shells in continuous casting molds,are important limitations for developing the ... Occasional irregular initial solidification phenomena,including stickers,deep oscillation marks,depressions,and surface cracks of strand shells in continuous casting molds,are important limitations for developing the high-efficiency continuous casting of steels.The application of mold thermal monitoring(MTM) systems,which use thermocouples to detect and respond to temperature variations in molds,has become an effective method to address irregular initial solidification phenomena.Such systems are widely applied in numerous steel companies for sticker breakout prediction.However,monitoring the surface defects of strands remains immature.Hence,indepth research is necessary to utilize the potential advantages and comprehensive monitoring of MTM systems.This paper summarizes what is included in the irregular initial solidification phenomena and systematically reviews the current state of research on these phenomena by the MTM systems.Furthermore,the influences of mold slag behavior on monitoring these phenomena are analyzed.Finally,the remaining problems of the formation mechanisms and investigations of irregular initial solidification phenomena are discussed,and future research directions are proposed. 展开更多
关键词 irregular initial solidification mold thermal monitoring continuous casting mold slag THERMOCOUPLE
下载PDF
上一页 1 2 230 下一页 到第
使用帮助 返回顶部