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Toluene Processed All-Polymer Solar Cells with 18%Efficiency and Enhanced Stability Enabled by Solid Additive:Comparison Between Sequential-Processing and Blend-Casting 被引量:1
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作者 Guoping Zhang Chaoyue Zhao +13 位作者 Liangxiang Zhu Lihong Wang Wenzhao Xiong Huawei Hu Qing Bai Yaping Wang Chen Xie Peng You He Yan Dan Wu Tao Yang Mingxia Qiu Shunpu Li Guangye Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第4期247-254,共8页
The emergence of polymerized small molecule acceptors(PSMAs)has significantly improved the performance of all-polymer solar cells(all-PSCs).However,the pace of device engineering lacks behind that of materials develop... The emergence of polymerized small molecule acceptors(PSMAs)has significantly improved the performance of all-polymer solar cells(all-PSCs).However,the pace of device engineering lacks behind that of materials development,so that a majority of the PSMAs have not fulfilled their potentials.Furthermore,most high-performance all-PSCs rely on the use of chloroform as the processing solvent.For instance,the recent highperformance PSMA,named PJ1-γ,with high LUMO,and HOMO levels,could only achieve a PCE of 16.1%with a high-energy-level donor(JD40)using chloroform.Herein,we present a methodology combining sequential processing(SqP)with the addition of 0.5%wt PC_(71)BM as a solid additive(SA)to achieve an impressive efficiency of 18.0%for all-PSCs processed from toluene,an aromatic hydrocarbon solvent.Compared to the conventional blend-casting(BC)method whose best efficiency(16.7%)could only be achieved using chloroform,the SqP method significantly boosted the device efficiency using toluene as the processing solvent.In addition,the donor we employ is the classic PM6 that has deeper energy levels than JD40,which provides low energy loss for the device.We compare the results with another PSMA(PYF-T-o)with the same method.Finally,an improved photostability of the SqP devices with the incorporation of SA is demonstrated. 展开更多
关键词 all-polymers solar cells sequential processing solid additive
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Prediction of corrosion rate for friction stir processed WE43 alloy by combining PSO-based virtual sample generation and machine learning 被引量:1
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作者 Annayath Maqbool Abdul Khalad Noor Zaman Khan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1518-1528,共11页
The corrosion rate is a crucial factor that impacts the longevity of materials in different applications.After undergoing friction stir processing(FSP),the refined grain structure leads to a notable decrease in corros... The corrosion rate is a crucial factor that impacts the longevity of materials in different applications.After undergoing friction stir processing(FSP),the refined grain structure leads to a notable decrease in corrosion rate.However,a better understanding of the correlation between the FSP process parameters and the corrosion rate is still lacking.The current study used machine learning to establish the relationship between the corrosion rate and FSP process parameters(rotational speed,traverse speed,and shoulder diameter)for WE43 alloy.The Taguchi L27 design of experiments was used for the experimental analysis.In addition,synthetic data was generated using particle swarm optimization for virtual sample generation(VSG).The application of VSG has led to an increase in the prediction accuracy of machine learning models.A sensitivity analysis was performed using Shapley Additive Explanations to determine the key factors affecting the corrosion rate.The shoulder diameter had a significant impact in comparison to the traverse speed.A graphical user interface(GUI)has been created to predict the corrosion rate using the identified factors.This study focuses on the WE43 alloy,but its findings can also be used to predict the corrosion rate of other magnesium alloys. 展开更多
关键词 Corrosion rate Friction stir processing Virtual sample generation Particle swarm optimization Machine learning Graphical user interface
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Predicting grain size-dependent superplastic properties in friction stir processed ZK30 magnesium alloy with machine learning methods
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作者 Farid Bahari-Sambran Fernando Carreno +1 位作者 C.M.Cepeda-Jiménez Alberto Orozco-Caballero 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第5期1931-1943,共13页
The aim of this work is to predict,for the first time,the high temperature flow stress dependency with the grain size and the underlaid deformation mechanism using two machine learning models,random forest(RF)and arti... The aim of this work is to predict,for the first time,the high temperature flow stress dependency with the grain size and the underlaid deformation mechanism using two machine learning models,random forest(RF)and artificial neural network(ANN).With that purpose,a ZK30 magnesium alloy was friction stir processed(FSP)using three different severe conditions to obtain fine grain microstructures(with average grain sizes between 2 and 3μm)prone to extensive superplastic response.The three friction stir processed samples clearly deformed by grain boundary sliding(GBS)deformation mechanism at high temperatures.The maximum elongations to failure,well over 400% at high strain rate of 10^(-2)s^(-1),were reached at 400℃ in the material with coarsest grain size of 2.8μm,and at 300℃ for the finest grain size of 2μm.Nevertheless,the superplastic response decreased at 350℃ and 400℃ due to thermal instabilities and grain coarsening,which makes it difficult to assess the operative deformation mechanism at such temperatures.This work highlights that the machine learning models considered,especially the ANN model with higher accuracy in predicting flow stress values,allow determining adequately the superplastic creep behavior including other possible grain size scenarios. 展开更多
关键词 Machine learning Artificial intelligence Magnesium alloys SUPERPLASTICITY Friction stir processing Grain coarsening
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Combined Insights from Leachate Structure and Microstructure Characteristics for Eating Quality of Convenience Rice Processed by Super-Heated and Pressurized Steam Technologies
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作者 Mingyo HA Hyo-Young JEONG +1 位作者 Ju Hun LEE Hyun-Jung CHUNG 《Rice science》 SCIE CSCD 2024年第4期475-488,I0035,I0036,共16页
Convenience rice has become widely popular due to its easy availability for cooking. This study investigated the starch structure and composition of leachate and the microstructure of reheated convenience rice using n... Convenience rice has become widely popular due to its easy availability for cooking. This study investigated the starch structure and composition of leachate and the microstructure of reheated convenience rice using novel processing technologies: super-heated steaming(SHS), auto-electric cooking(AEC), and pressurized-steam cooking(PSC). Additionally, the effect of two different target water contents(58% and 63%) was also evaluated. The PSC_63% sample had the highest total solids and amylopectin amount in the leachate. The amylopectin amount in the leachate differed significantly based on the targeted water content. Morphological characterization revealed that the swelling of starch and the coated layer on the surface of rice grains were most pronounced in the PSC_63% sample due to the pressure processing. The textural hardness of the AEC_58% sample was much higher than that of the other samples. The PSC_63% sample had the highest textural adhesiveness value, which can be attributed to the highest amylopectin amount in the leachate. Sensory characterization showed that the PSC_63% sample had the highest glossiness, whiteness, moistness, and overall acceptability. The principal component analysis score plots presented substantial differences in the leachate and textural and sensory characteristics of reheated convenience rice among the different processing technologies. 展开更多
关键词 reheated convenience rice starch structure LEACHATE multi-scale structure eating quality processing technology
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Fast and Balanced Charge Transport Enabled by Solution-Processed Metal Oxide Layers for Efficient and Stable Inverted Perovskite Solar Cells
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作者 Jing Zhang James Mcgettrick +11 位作者 Kangyu Ji Jinxin Bi Thomas Webb Xueping Liu Dongtao Liu Aobo Ren Yuren Xiang Bowei Li Vlad Stolojan Trystan Watson Samuel D.Stranks Wei Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期240-248,共9页
Metal oxide charge transport materials are preferable for realizing long-term stable and potentially low-cost perovskite solar cells(PSCs).However,due to some technical difficulties(e.g.,intricate fabrication protocol... Metal oxide charge transport materials are preferable for realizing long-term stable and potentially low-cost perovskite solar cells(PSCs).However,due to some technical difficulties(e.g.,intricate fabrication protocols,high-temperature heating process,incompatible solvents,etc.),it is still challenging to achieve efficient and reliable all-metal-oxide-based devices.Here,we developed efficient inverted PSCs(IPSCs)based on solution-processed nickel oxide(NiO_(x))and tin oxide(SnO_(2))nanoparticles,working as hole and electron transport materials respectively,enabling a fast and balanced charge transfer for photogenerated charge carriers.Through further understanding and optimizing the perovskite/metal oxide interfaces,we have realized an outstanding power conversion efficiency(PCE)of 23.5%(the bandgap of the perovskite is 1.62 eV),which is the highest efficiency among IPSCs based on all-metal-oxide charge transport materials.Thanks to these stable metal oxides and improved interface properties,ambient stability(retaining 95%of initial PCE after 1 month),thermal stability(retaining 80%of initial PCE after 2 weeks)and light stability(retaining 90%of initial PCE after 1000 hours aging)of resultant devices are enhanced significantly.In addition,owing to the low-temperature fabrication procedures of the entire device,we have obtained a PCE of over 21%for flexible IPSCs with enhanced operational stability. 展开更多
关键词 fast and balanced charge transfer inverted perovskite solar cells long-term stability low-temperature processing metal oxides
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Dendritic spine degeneration:a primary mechanism in the aging process
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作者 Gonzalo Flores Leonardo Aguilar-Hernández +3 位作者 Fernado García-Dolores Humberto Nicolini Andrea Judith Vázquez-Hernández Hiram Tendilla-Beltrán 《Neural Regeneration Research》 SCIE CAS 2025年第6期1696-1698,共3页
Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a w... Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(Mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(Mayer et al., 2022;AguilarHernández et al., 2023). 展开更多
关键词 AGING process STRESS
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Enhancing performance of low-temperature processed CsPbI2Br all-inorganic perovskite solar cells using polyethylene oxide-modified TiO_(2)
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作者 Xu Zhao Naitao Gao +2 位作者 Shengcheng Wu Shaozhen Li Sujuan Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期786-794,共9页
CsPbX_(3)-based(X=I,Br,Cl)inorganic perovskite solar cells(PSCs)prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability.However,the high trap state d... CsPbX_(3)-based(X=I,Br,Cl)inorganic perovskite solar cells(PSCs)prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability.However,the high trap state density and serious charge recombination between low-temperature processed TiO_(2)film and inorganic perovskite layer interface seriously restrict the performance of all-inorganic PSCs.Here a thin polyethylene oxide(PEO)layer is employed to modify TiO_(2)film to passivate traps and promote carrier collection.The impacts of PEO layer on microstructure and photoelectric characteristics of TiO_(2)film and related devices are systematically studied.Characterization results suggest that PEO modification can reduce the surface roughness of TiO_(2)film,decrease its average surface potential,and passivate trap states.At optimal conditions,the champion efficiency of CsPbI_(2)Br PSCs with PEO-modified TiO_(2)(PEO-PSCs)has been improved to 11.24%from 9.03%of reference PSCs.Moreover,the hysteresis behavior and charge recombination have been suppressed in PEO-PSCs. 展开更多
关键词 polyethylene oxide-modified TiO_(2) film low-temperature process CsPbI_(2)Br-based all-inorganic perovskite solar cells photo-voltaic performance
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Colorectal cancer’s burden attributable to a diet high in processed meat in the Belt and Road Initiative countries
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作者 Gu Liu Chang-Min Li +5 位作者 Fei Xie Qi-Lai Li Liang-Yan Liao Wen-Jun Jiang Xiao-Pan Li Guan-Ming Lu 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第1期182-196,共15页
BACKGROUND Colorectal cancer(CRC)plays a significant role in morbidity,mortality,and economic cost in the Belt and Road Initiative(“B and R”)countries.In addition,these countries have a substantial consumption of pr... BACKGROUND Colorectal cancer(CRC)plays a significant role in morbidity,mortality,and economic cost in the Belt and Road Initiative(“B and R”)countries.In addition,these countries have a substantial consumption of processed meat.However,the burden and trend of CRC in relation to the consumption of a diet high in processed meat(DHPM-CRC)in these“B and R”countries remain unknown.AIM To analyze the burden and trend of DHPM-CRC in the“B and R”countries from 1990 to 2019.METHODS We used the 2019 Global Burden of Disease Study to collate information regarding the burden of DHPM-CRC.Numbers and age-standardized rates(ASRs)of deaths along with the disability-adjusted life years(DALYs)were determined among the“B and R”countries in 1990 and 2019.Using joinpoint regression analysis,the average annual percent change(AAPC)was used to analyze the temporal trends of age-standardized DALYs rate(ASDALR)from 1990 to 2019 and in the final decade(2010–2019).RESULTS We found geographical differences in the burden of DHPM-CRC among“B and R”countries,with the three highest-ranking countries being the Russian Federation,China,and Ukraine in 1990,and China,the Russian Federation,and Poland in 2019.The burden of DHPM-CRC generally increased in most member countries from 1990 to 2019(all P<0.05).The absolute number of deaths and DALYs in DHPM-CRC were 3151.15[95%uncertainty interval(UI)665.74-5696.64]and 83249.31(95%UI 15628.64-151956.31)in China in 2019.However,the number of deaths(2627.57-2528.51)and DALYs(65867.39-55378.65)for DHPM-CRC in the Russian Federation has declined.The fastest increase in ASDALR for DHPM-CRC was observed in Vietnam,Southeast Asia,with an AAPC value of 3.90%[95%confidence interval(CI):3.63%-4.16%],whereas the fastest decline was observed in Kyrgyzstan,Central Asia,with an AAPC value of-2.05%(95%CI:-2.37%to-1.73%).A substantial upward trend in ASR of mortality,years lived with disability,years of life lost,and DALYs from DHPM-CRC changes in 1990-2019 and the final decade(2010-2019)for most Maritime Silk Route members in East Asia,South Asia,Southeast Asia,North Africa,and the Middle East,as well as Central Europe,while those of the most Land Silk Route members in Central Asia and Eastern Europe have decreased markedly(all P<0.05).The ASDALR for DHPM-CRC increased more in males than in females(all P<0.05).For those aged 50-74 years,the ASDALR for DHPM-CRC in 40 members exhibited an increasing trend,except for 20 members,including 7 members in Central Asia,Maldives,and 12 high or high-middle social development index(SDI)members in other regions(all P<0.05).CONCLUSION The burden of DHPM-CRC varies substantially across“B and R”countries and threatens public health.Relevant evidence-based policies and interventions tailored to the different trends of countries in SDIs or Silk Routes should be adopted to reduce the future burden of CRC in“B and R”countries via extensive collaboration. 展开更多
关键词 Belt and Road Initiative countries Colorectal cancer Burden of disease Dietary risk factors processed meat Disability-adjusted life years Trend analysis
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基于Arduino与Processing的心率检测计设计研究 被引量:1
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作者 臧红波 华拓 管志岳 《家电维修》 2024年第3期74-76,共3页
随着社会经济的高速发展,人们的物质生活也有了极大的提高,但同时也伴随着各种疾病的到来,身体健康已经成为人们普遍关注的焦点,因此,心率检测仪、血压计、血糖仪等各种家用医疗监测仪器已经逐渐融入日常生活。心脏病是人们难以预防的... 随着社会经济的高速发展,人们的物质生活也有了极大的提高,但同时也伴随着各种疾病的到来,身体健康已经成为人们普遍关注的焦点,因此,心率检测仪、血压计、血糖仪等各种家用医疗监测仪器已经逐渐融入日常生活。心脏病是人们难以预防的突发致命疾病之一,本文介绍的是一款基于Arduino【是基于易用硬件和软件的原型开源平台,包由可编程的电路板(简称微控制器),以及集成开发环境(称为Arduino IDE)的现成软件组成】Processing(开源编程语言,包括编辑器、编译器、展示器)的简易心率检测计系统,其功能实用、操作简单,可以测量心率,当超出正常心率范围时及时预警,是一款便携的实时心率测试仪。 展开更多
关键词 Arduino processing 心率检测计 设计研究
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Studies on the Components of Crude and Processed Fructus Corni by ESI-MS^n 被引量:2
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作者 ZHOU Li-li WU Guo-guang +1 位作者 LIU Zhi-qiang LIU Shu-ying 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第3期270-274,共5页
The components of crude and processed Fructus Corni were investigated by means of electrospray ionization-tandem mass spectrometry(ESI-MSn) technique in the negative ion mode. Compared with those of crude Fructus Co... The components of crude and processed Fructus Corni were investigated by means of electrospray ionization-tandem mass spectrometry(ESI-MSn) technique in the negative ion mode. Compared with those of crude Fructus Corni, the chemical components of the processed Fructus Corni were changed both in quality and in quantity. From the ESI-MS spectra of the crude and processed Fructus Corni, six peaks were selected to establish the characte-ristic ESI-MS peaks. Several factors in the processing procedure were examined. The experimental results demonstrate that the chemical reactions that occurred in the processing procedure can be used for the elucidation of the processed mechanism of Fructus Corni, which is regularly affected by the processing conditions. The present article provides both the chemistry evidence for the understanding of the processing procedure of Fructus Corni and the specific methodology for the research of the processing procedure and quality identification of traditional Chinese medicine. 展开更多
关键词 Fructus Corni ESI-MSN processed
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Microstructure Evolution of Cu-Pb Monotectic Alloys Processed in Drop Tube 被引量:2
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作者 Cao, CD Wei, BB 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2002年第1期73-76,共4页
Rapid solidification of Cu-Pb monotectic alloys has been accomplished during free fall in a 3 m drop tube. Both macrosegregated and uniformly dispersed structures are observed in Cu-40 wt pct Pb alloy droplets, wherea... Rapid solidification of Cu-Pb monotectic alloys has been accomplished during free fall in a 3 m drop tube. Both macrosegregated and uniformly dispersed structures are observed in Cu-40 wt pct Pb alloy droplets, whereas droplets of composition Cu-64 wt pct Pb exhibit only macrosegregation morphologies. The microstructures are strongly dependent on droplet size. The higher undercooling tends to facilitate liquid phase separation and results in more extensive macrosegregation in smaller droplets. There exists a pronounced tendency for the Pb-rich liquid to occupy the surface of the droplets of both compositions, resulting from the quite lower surface tension of the Pb-rich phase and causing a Pb-rich layer at the surface of the solidified droplet. The nucleation of monotectic cells in the Cu-40 wt pct Pb droplets with dispersed structures preferentially occurs at the droplet surface. A single nucleation event takes place more frequently as droplet size is reduced. 展开更多
关键词 Rapid solidification UNDERCOOLING IMMISCIBILITY Containerless processing Low-gravity Monotectic
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Effect of processing routes on microstructure and mechanical properties of 2014 Al alloy processed by equal channel angular pressing 被引量:7
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作者 P.VENKATACHALAM S.RAMESH KUMAR +2 位作者 B.RAVISANKAR V.THOMAS PAUL M.VIJAYALAKSHMI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第10期1822-1828,共7页
Al-Cu alloy was deformed through equal channel angular pressing(ECAP) by routes A,Ba,Bc and C up to 5 passes.ECAP was done using a 90° die for three different conditions,namely 1) as received,2) solutionised at 7... Al-Cu alloy was deformed through equal channel angular pressing(ECAP) by routes A,Ba,Bc and C up to 5 passes.ECAP was done using a 90° die for three different conditions,namely 1) as received,2) solutionised at 768 K for 1 h and 3) solutionised at 768 K for 1 h + aged at 468 K for 5 h.The microstructure,microhardness and tensile strength were studied for all the three conditions and four routes.Significant improvement in hardness(HV 184 after five passes) and strength(602 MPa after three passes) was observed in solutionised and aged 2014 Al alloy deformed through route Bc.Microstructure evolution was reasonably equiaxed in route Bc with aspect ratio of 1.6.Solutionised and aged 2014 Al alloy deformed through route Bc was identified to have better microstructure and mechanical property than the other processing routes and conditions. 展开更多
关键词 ECAP processing route 2014 aluminium alloy
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Consumption of red and processed meat and esophageal cancer risk:Meta-analysis 被引量:2
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作者 Yuni Choi Sujin Song +1 位作者 Yoonju Song Jung Eun Lee 《World Journal of Gastroenterology》 SCIE CAS 2013年第7期1020-1029,共10页
To summarize the evidence about the association between red and processed meat intake and the risk of esophageal cancer,we systematically searched the PubMed and EMBASE databases up to May 2012,with a restriction to E... To summarize the evidence about the association between red and processed meat intake and the risk of esophageal cancer,we systematically searched the PubMed and EMBASE databases up to May 2012,with a restriction to English publications,and the references of the retrieved articles.We combined the studyspecific relative risks(RRs) and 95%CI,comparing the highest with the lowest categories of consumption by using a random-effects model.A total of 4 cohort studies and 23 case-control studies were included in the meta-analysis.The combined RRs(95%CI) of the cohort studies comparing the highest and lowest categories were 1.26(1.00-1.59) for red meat and 1.25(0.83-1.86) for processed meat.For the case-control studies,the combined RRs(95%CI) comparing the highest and lowest categories were 1.44(1.16-1.80)for red meat and 1.36(1.07-1.74) for processed meat.Findings from this meta-analysis suggest that a higher consumption of red meat was associated with a greater risk of esophageal cancer. 展开更多
关键词 Cohort STUDY CASE-CONTROL STUDY META-ANALYSIS RED MEAT processed MEAT ESOPHAGEAL cancer
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Microstructure and Properties of Mg-12Gd-3Y-0.5Zr Alloys Processed by ECAP and Extrusion 被引量:2
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作者 朱荣 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第6期1128-1132,共5页
Equal channel angular pressing (ECAP) processing and conventional extrusion (Ex) were applied to the Mg-12Gd-3Y-0.5Zr (wt%) magnesium alloy in order to evaluate the potential improvement in the mechanical proper... Equal channel angular pressing (ECAP) processing and conventional extrusion (Ex) were applied to the Mg-12Gd-3Y-0.5Zr (wt%) magnesium alloy in order to evaluate the potential improvement in the mechanical properties. The ECAP experiment was conducted at 380 ℃ in a die having an included angle of 90° between two channels by the Bc route with the billet rotated by 90° about its longitudinal axis. Subsequently, some billets were processed by conventional extrusion at 300 ℃. The microstructures were examined by X-ray diffraction (XRD), optical microscopy and transmission electron microscopy (TEM). The experimental results indicate that the grain size is refined effectively, but the basal planes are highly inclined (about 40o) from the extrusion axis introduced by ECAP, which impairs the grain boundary strengthening effect. The conventional extrusion, following the ECAP, can modify the grains in hard orientation. Based on grain boundary strengthening due to ECAP and texture strengthening due to Ex, the strength is improved effectively. The enhanced activity of the non-basal slips, due to the refined grains and the reduction in c/a ratio, is responsible for good ductility and high strain hardening rate in samples obtained by the two-step process. 展开更多
关键词 magnesium alloy equal channel angular pressing thermomechanical processing TEXTURE
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Effects of Heat Treatment on Hardness and Dry Wear Properties of a Semi-Solid Processed Fe-27 wt pct Cr-2.9 wt pct C Cast Iron 被引量:2
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作者 A.Wiengmoon T.Chairuangsri +2 位作者 N.Chomsang N.Poolthong J.T.H.Pearce 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2008年第3期330-334,共5页
EfFects of heat treatments on hardness and dry wear properties of a semi-solid processed Fe-26.96 wt pct Cr- 2.91 wt pct C cast iron were studied. Heat treatments included tempering at 500℃, destabilisation at 1075℃... EfFects of heat treatments on hardness and dry wear properties of a semi-solid processed Fe-26.96 wt pct Cr- 2.91 wt pct C cast iron were studied. Heat treatments included tempering at 500℃, destabilisation at 1075℃ and destabilisation at 1075℃ plus tempering at 500℃, all followed by air cooling. Electron microscopy revealed that, in the as-cast condition, the primary proeutectic austenite was round in shape while the eutectic M7C3 carbide was found as radiating clusters mixed with directional clusters. Tempering did not change the microstructure significantly when observed by scanning or transmission electron microscopy. Destabilisation followed by air cooling led to a precipitation of secondary M23C6 carbide and a transformation of the primary austenite to martensite. Precipitation behaviour is comparable to that observed in the conventionally cast iron. Tempering after destabilisation resulted in a higher amount of secondary carbide precipitation within the tempered martensite in the eutectic structure. Vickers macrohardness and microhardness in the proeutectic zones were measured. Dry wear properties were tested by using a pin-on-disc method. The maximum hardness and the lowest dry wear rate were obtained from the destabilisation-plus-tempering heat treatment due to the precipitation of secondary carbides within the martensite matrix and a possible reduction in the retained austenite. 展开更多
关键词 Semi-solid process High chromium cast iron Heat treatment HARDNESS Wear
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Superplasticity of a friction stir processed overaged WE54 magnesium alloy 被引量:3
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作者 Oscar A.Ruano Marta Alvarez-Leal +1 位作者 Alberto Orozco-Caballero Fernando Carreño 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2022年第11期3156-3166,共11页
The coarse-grained WE54 magnesium alloy was heat treated in order to have minimum hardness minimizing the effects of precipitates and solid solution. Friction stir processing(FSP) was applied in severe conditions to o... The coarse-grained WE54 magnesium alloy was heat treated in order to have minimum hardness minimizing the effects of precipitates and solid solution. Friction stir processing(FSP) was applied in severe conditions to obtain fine, equiaxed and highly misoriented grains, with grain sizes even less than 1 μm. The high severity of processing demonstrated to have a strong impact in the microstructure. Consequently,the processed materials exhibited excellent superplasticity at the high strain rate 10^(-2)s^(-1), and temperatures between 300 and 400 ℃. The maximum tensile superplastic elongation of 756% was achieved at 400 ℃ thanks to the operation of grain boundary sliding mechanism(GBS). Besides the new data obtained through tensile testing, the paper deals with a transcendental question regarding the large differences in strain rate values at a given stress in the superplastic regime at maximum elongation compared to other magnesium-based alloys. With this is mind, 19 magnesium alloys from 22 different investigations were analyzed to give some light to this behavior that never was treated before. It is proposed that this behavior has to be attributed to the accommodation process, necessary for GBS to occur, which is hindered by reinforcing solutes. 展开更多
关键词 WE54 magnesium alloy Friction stir processing processing severity SUPERPLASTICITY Grain boundary sliding SOLUTES
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Microstructures and mechanical properties of friction stir processed Mge2.0Nde0.3Zne1.0Zr magnesium alloy 被引量:9
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作者 F.Y.Zheng Y.J.Wu +3 位作者 L.M.Peng X.W.Li P.H.Fu W.J.Ding 《Journal of Magnesium and Alloys》 SCIE EI CAS 2013年第2期122-127,共6页
The effect of Friction stir process(FSP)parameters on the microstructure and mechanical properties of an extruded Mge2.0Nde0.3Zne1.0Zr(wt.%)alloy was investigated in this paper.The alloy was friction stir processed wi... The effect of Friction stir process(FSP)parameters on the microstructure and mechanical properties of an extruded Mge2.0Nde0.3Zne1.0Zr(wt.%)alloy was investigated in this paper.The alloy was friction stir processed with different passes:single-pass,three-pass and five-pass,under a tool rotation rate of 800μm and a traverse speed of 200 mm min^(-1).FSP results in remarkable grain refinement of the extruded alloy(average grain size w3.8 mm as 3 passes)and almost complete dissolution of the Mg_(12)Nd phase in the matrix.With the increase of pass,the average grain size in the stir zone(SZ)is decreased firstly and then increases.The Vikers hardness of SZs in all FSPed samples is higher than that of the parent material(PM).Tensile tests at room-temperature show that the tensile strengths of the stir zones along the FSP advancing direction are slightly lower than those of PM.However,the elongations are remarkably improved from 13.0%for PM to 24.5%for SZ FSPed with three-passes.These improved tensile properties are attributed to the microstructure refinement,dynamic recrystallization and dissolution of the Mg_(12)Nd phase. 展开更多
关键词 Mg-Nd-Zn-Zr alloy Friction stir processing Grain refinement Dynamic recrystallization
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Effects of Different Processed Products of Radix Codonopsis on Intestinal Flora of Rats with Spleen Deficiency 被引量:2
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作者 Jiabao MA Zhengteng YANG +4 位作者 Jiangcun WEI Jian CUI Song CHEN Dongmei HUANG Lifu WEI 《Medicinal Plant》 CAS 2020年第1期63-66,共4页
[Objectives]This study aimed to observe the effects of different processed products of Radix Codonopsis on intestinal flora in rats with spleen deficiency.[Methods]Rat models with spleen deficiency were established by... [Objectives]This study aimed to observe the effects of different processed products of Radix Codonopsis on intestinal flora in rats with spleen deficiency.[Methods]Rat models with spleen deficiency were established by bitter-cold purgation method with Radix et Rhizoma Rhei.Normal group,model group,Radix Codonopsis group,fried Radix Codonopsis group,rice-fried Radix Codonopsis group,honey-fried Radix Codonopsis group and bran-fired Radix Codonopsis group were designed.After subjecting to corresponding treatments,the changes in the quantity of intestinal microorganisms of the rats were detected.[Results]There was no significant change in the quantity of intestinal microorganisms of the rats in the normal group and model group.The rats in the rice-fried Radix Codonopsis group were administered after successful modeling,and the abundance of Bifidobacterium and Lactobacillus in the intestines of the rats increased,and the quantity of Escherichia coli and Staphylococci reduced.The rats in the Radix Codonopsis group,fried Radix Codonopsis groups,honey-fried Radix Codonopsis group and bran-fried Radix Codonopsis group were administered after successful modeling,and the abundance of Bifidobacterium and Lactobacillus in the intestines of the rats increased(the increases were smaller than those in the rice-fried Radix Codonopsis group),and the abundance of E.coli and Staphylococci reduced,close to normal levels.[Conclusions]Different processed products of Radix Codonopsis have obvious regulation effect on intestinal flora of rats with spleen deficiency,and the regulation effect of rice-fried Radix Codonopsis on rats with spleen deficiency is better than that of Radix Codonopsis,fried Radix Codonopsis,honey-fried Radix Codonopsis and bran-fried Radix Codonopsis. 展开更多
关键词 RADIX CODONOPSIS processed product INTESTINAL FLORA SPLEEN DEFICIENCY rat model
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Microstructure of Laser Processed T10 Carbon Tool Steel 被引量:1
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作者 Xianzhang BU Fine Mech.Mater.and Technol.Dept.,Changchun Institute of Optics and Fine Mechanics,Changchun,130022,ChinaHongying WANG Zhang LI Jiandong HU Microanalysis Center,Jilin University of Technology,Changchun,130025,China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1993年第4期289-292,共4页
The microstructure of the laser melted 1.0%C tool steel have been investigated.The region affected by the laser can be subdivided into 3 zones,which consist of a melted region at the surface,a zone with solid state tr... The microstructure of the laser melted 1.0%C tool steel have been investigated.The region affected by the laser can be subdivided into 3 zones,which consist of a melted region at the surface,a zone with solid state transformation and the area adjacent to the unaffected substrate where cementite is slightly dissolved.The melted zone possessed a cellular growth morphology consisting of austenite and martensite.The carbon content of the austenite was measured to be over 1 wt-%.A great deal of retained austenite and twinned martensite were found in the first two zones(the melted and solid transformed). 展开更多
关键词 laser process MICROSTRUCTURE melted zones
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A new isoflavane from processed Astragalus membranaceus 被引量:1
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作者 Wei Liu Jing Chen +2 位作者 Wen Jian Zuo Xian Li Jin Hui Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第9期1092-1094,共3页
A new isoflavane named astraganoside, together with five known compounds had been isolated from the processed Astragralus membranaceus. The structure of the novel compound was elucidated as (3R, 4R)-3-(2-hydroxy-3,4-d... A new isoflavane named astraganoside, together with five known compounds had been isolated from the processed Astragralus membranaceus. The structure of the novel compound was elucidated as (3R, 4R)-3-(2-hydroxy-3,4-dimethoxyphenyl)chroman-4,7-diol-7-O-β-d-glucopyranoside (1) based on spectroscopic methods including UV, IR, ESI-MS, 1D NMR and 2D NMR techniques. 展开更多
关键词 processed Astragalus membranaceus Isoflavane Astraganoside
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