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The combined effects of North Atlantic Oscillation and Western Pacific teleconnection on winter temperature in Eastern Asia during 1980−2021 被引量:1
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作者 Ziqun Zhang Hongyan Cui +2 位作者 Baoxu Chen Hong Cai Pin Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第10期1-9,共9页
As important atmospheric circulation patterns in Northern Hemisphere(NH),the North Atlantic Oscillation(NAO)and the Western Pacific teleconnection(WP)affect the winter climate in Eurasia.In order to explore the combin... As important atmospheric circulation patterns in Northern Hemisphere(NH),the North Atlantic Oscillation(NAO)and the Western Pacific teleconnection(WP)affect the winter climate in Eurasia.In order to explore the combined effects of NAO and WP on East Asian(EA)temperature,the NAO and WP indices are divided into four phases from 1980−2021:the positive NAO and WP phase(NAO+/WP+),the negative NAO and WP phase(NAO−/WP−),the positive NAO and negative WP phase(NAO+/WP−),the negative NAO and positive WP phase(NAO−/WP+).In the phase of NAO+/WP+,the low geopotential height(GH)stays in north of EA at 50°−80°N;the surface air temperature anomaly(SATA)is 0.8−1℃lower than Southern Asian.In the phase of NAO−/WP−,the center of high temperature and GH locate in the northeast of EA;the cold air spreads to Southern Asia,causing the SATA decreases 1−1.5℃.In the phase of NAO+/WP−,the high GH belt is formed at 55°−80°N.Meanwhile,the center of high SATA locates in the north of Asia that increases 0.8−1.1℃.The cold airflow causes temperature dropping 0.5−1℃in the south of EA.The SATA improves 0.5−1.5℃in south of EA in the phase of NAO−/WP+.The belt of high GH is formed at 25°−50°N,and blocks the cold air which from Siberia.The NAO and WP generate two warped plate pressure structures in NH,and affect the temperature by different pressure configurations.NAO and WP form different GH,and GH acts to block and push airflow by affecting the air pressure,then causes the temperature to be different from the north and south of EA.Finally,the multiple linear regression result shows that NAO and WP are weakened by each other such as the phase of NAO+/WP+and NAO−/WP−. 展开更多
关键词 North Atlantic Oscillation(NAO) Western Pacific teleconnection(WP) winter temperature combined effect Eastern Asia
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Genetic variability predicting breeding potential of upland cotton(Gossypium hirsutum L.)for high temperature tolerance 被引量:2
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作者 FAROOQ Amjad SHAKEEL Amir +5 位作者 SAEED Asif FAROOQ Jehanzeb RIZWAN Muhammad CHATTHA Waqas Shafqat SARWAR Ghulam RAMZAN Yasir 《Journal of Cotton Research》 CAS 2023年第2期81-97,共17页
Background High temperature stress at peak flowering stage of cotton is a major hindrance for crop potential.This study aimed to increase genetic divergence regarding heat tolerance in newly developed cultivars and hy... Background High temperature stress at peak flowering stage of cotton is a major hindrance for crop potential.This study aimed to increase genetic divergence regarding heat tolerance in newly developed cultivars and hybrids.Fifty cotton genotypes and 40 F1(hybrids)were tested under field conditions following the treatments,viz.,high temperature stress and control at peak flowering stage in August and October under April and June sowing,respectively.Results The mean squares revealed significant differences among genotypes,treatments,genotype×treatment for relative cell injury,chlorophyll contents,canopy temperature,boll retention and seed cotton yield per plant.The genetic diversity among 50 genotypes was analyzed through cluster analysis and heat susceptibility index(HSI).The heat tolerant genotypes including FH-Noor,NIAB-545,FH-466,FH-Lalazar,FH-458,NIAB-878,IR-NIBGE-8,Weal-AGShahkar,and heat sensitive,i.e.,CIM-602,Silky-3,FH-326,SLH-12 and FH-442 were hybridized in line×tester fashion to produce F1 populations.The breeding materials’populations(40 F1)revealed higher specific combining ability variances along with dominance variances,decided the non-additive type gene action for all the traits.The best general combining ability effects for most of the traits were displayed by the lines,i.e.,FH-Lalazar,NIAB-878 along with testers FH-326 and Silky-3.Specific combining ability effects and better-parent heterosis were showed by the crosses,viz.,FH-Lalazar×Silky-3,FH-Lalazar×FH-326,NIAB-878×Silky-3,and NIAB-878×FH-326 for seed cotton yield and yield contributing traits under high temperature stress.Conclusion Heterosis breeding should be carried out in the presence of non-additive type gene action for all the studied traits.The best combiner parents with better-parent heterosis may be used in crossing program to develop high yielding cultivars,and hybrids for high temperature stress tolerance. 展开更多
关键词 high temperature Upland cotton Peak flowering HETEROSIS Gene action combining ability
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The Combined Effects of High Temperature and Carbon Monoxide on Heat Stress Response 被引量:2
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作者 邬堂春 贺涵贞 +4 位作者 吴扬 徐代根 屈伸 冯家德 张国高 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1995年第3期178-183,共6页
In this study,we have examined the effects of exposure to high temperature, carbon inonoxideor a combination of both conditions in a model system,the rat and in industrial workers.In the rat liver, HSP70 mRNA and HSP7... In this study,we have examined the effects of exposure to high temperature, carbon inonoxideor a combination of both conditions in a model system,the rat and in industrial workers.In the rat liver, HSP70 mRNA and HSP70 synthesis were measured by dot hybridization and western blot. The results showed that after a heat stress HSP70 mRNA and its product, HSP70 increased significantly and there was a synergism in the combined effects of high temperature and carbon monoxide exposure on the induction of HSP70 mRNA and HSP70 synthesis. Heat played a major role in this induction. The presence of antibodies to human HSP27, HSP60, HSP70,HSC73, HSP89 αand β in workers exposed to heat, carbon monoxide was also measured by western blot using purified HSPs as antigens. Plasma free amino acids were measured in the saine group of workers. The incidence of antibodies to HSP27 and HSP70 Was significantly higher in the workers working in an environment with extreme heat, and high carbon monoxide ernission than in a control group. The carbon monoxide exposed group showed the highest incidence of antibodies to HSPs. Although our previous results indicated that workers had an insufficient protein intake,plasma free amino acids tended to increase, especially in methionine and tryptophan two kinds of amino acids which are absent from the main stress protein, HSP70.These results suggest that the major problems that these workers may face are how to facilitate the use of plasma free amino acids and reduce the inhibition of synthesis of normal proteins when they are exposed to occupational harmful factors.These resultsalso add new information on the measurement of HSPs as a potential biomonitor to assess whether organisms are experiencing metabolic stress within their environment. 展开更多
关键词 high temperature4 carbon monoxide the combined effects HSP70 HSP70 mRNA antibodies to heat stress proteins plasma free amino acids
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Effects of Combined Instantaneous High-Pressure and Medium Temperature on Peroxidase Activity in Wax Gourd Juices 被引量:1
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作者 CHEN Cong gui, WANG Wu, ZHANG Li, FANG Hong mei and HE Jing min (School of Biology and Food Engineering, Hefei University of Technology, Hefei 230061, P.R.China) 《Agricultural Sciences in China》 CAS CSCD 2003年第9期1030-1034,共5页
Based on the instantaneous pressurization and depressurization produced by high pressure single pole cylinder pump and valve, the effects of the continuous processing on the peroxidase (POD) activity in wax gourd ju... Based on the instantaneous pressurization and depressurization produced by high pressure single pole cylinder pump and valve, the effects of the continuous processing on the peroxidase (POD) activity in wax gourd juices were investigated. Results showed that the processing factors such as pressure, temperature, pH and processing time are important to the POD activity. POD in crude juices could be inactivated apparently above 50 MPa(pH 4.6, 35℃, 4 min), and activated at 20 MPa ( P < 0.01). Its remarkable inactivation could also be observed at 45 and 55℃ (20 MPa, pH 4.6, 4 min), and the evident activation appears at the material temperature 35℃ ( P < 0.01). The pH 3.0 could destroy POD almost completely (20 MPa, 35℃, 4 min), while pH 6.0 could not influence apparently the POD activity in crude juices( P > 0.05). In addition, the rules of POD activity along with the treatment time are variational under different processing pressures. The higher the treating pressure is, the shorter the processing time is needed to inactivate POD. 展开更多
关键词 Instantaneous high pressure Medium temperature combined process POD ACTIVITY
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Effects of Combined Instantaneous High-Pressure and MediumTemperature on the Retention of Total Vitamin Cin Wax Gourd Juices 被引量:2
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作者 LIUJin-jie WANGWu +2 位作者 ZHANGLi HEJing-min CHENCong-gui 《Agricultural Sciences in China》 CAS CSCD 2003年第8期919-923,共5页
Based on the instantaneous high-pressure(IHP)produced by high-pressure single pole-cylinder pump, the effects of combining this pressure with medium temperature on the retention of total vitamin C(Vc)in wax gourd juic... Based on the instantaneous high-pressure(IHP)produced by high-pressure single pole-cylinder pump, the effects of combining this pressure with medium temperature on the retention of total vitamin C(Vc)in wax gourd juices were investigated under 20 - 80 MPa, 35 - 58℃, pH 3. 0 - 6. 0 and processing time 0-8 min. Results showed that the loss of Vc increased with elevated processing temperatures(50 MPa, 4 min). When the temperature of raw juices was 35℃, the retention of total Vc was higher under 40 - 60 MPa than that under the pressure < 40 MPa or > 60 MPa, and it was up to 94%(4 min). The retention of total Vc decreases slowly within 6 min, but rapidly after 6 min. The pH can also influence the retention of total Vc, and this retention can come to a highest point at pH 6.0. 展开更多
关键词 Instantaneous high-pressure Medium temperature combined process Vitamin C RETENTION
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Size effect of sandstone after high temperature under uniaxial compression 被引量:2
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作者 苏海健 靖洪文 +3 位作者 茅献彪 赵洪辉 尹乾 王辰 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1901-1908,共8页
Uniaxial compression tests on sandstone samples with five different sizes after high temperature processes were performed in order to investigate the size effect and its evolution. The test results show that the densi... Uniaxial compression tests on sandstone samples with five different sizes after high temperature processes were performed in order to investigate the size effect and its evolution. The test results show that the density, longitudinal wave velocity, peak strength, average modulus and secant modulus of sandstone decrease with the increase of temperature, however, peak strain increases gradually. With the increase of ratio of height to diameter, peak strength of sandstone decreases, which has an obvious size effect. A new theoretical model of size effect of sandstone material considering the influence of temperature is put forward, and with the increase of temperature, the size effect is more apparent. The threshold decreases gradually with the increase of temperature, and the deviations of the experimental values and the theoretical values are between 0.44% and 6.06%, which shows quite a credibility of the theoretical model. 展开更多
关键词 high temperature process SandSTONE size effect THRESHOLD
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Comparison of mechanical properties in high temperature and thermal treatment granite 被引量:20
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作者 尹土兵 舒荣华 +2 位作者 李夕兵 王品 刘希灵 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1926-1937,共12页
Static mechanical experiments were carried out on granite after and under different temperatures using an electro-hydraulic and servo-controlled material testing machine with a heating device. Variations in obvious fo... Static mechanical experiments were carried out on granite after and under different temperatures using an electro-hydraulic and servo-controlled material testing machine with a heating device. Variations in obvious form, stress-strain curve, peak strength, peak strain and elastic modulus with temperature were analyzed and the essence of rock failure modes was explored. The results indicate that, compared with granite after the high temperature treatment, the brittle-ductile transition critical temperature is lower, the densification stage is longer, the elastic modulus is smaller and the damage is larger under high temperature. In addition, the peak stress is lower and the peak strain is greater, but both of them change more obviously with the increase of temperature compared with that of granite after the high temperature treatment. Furthermore, the failure modes of granite after the high temperature treatment and under high temperature show a remarkable difference. Below 100 ℃, the failure modes of granite under both conditions are the same, presenting splitting failure. However, after 100 ℃, the failure modes of granite after the high temperature treatment and under high temperature present splitting failure and shear failure, respectively. 展开更多
关键词 GRANITE thermal treatment high temperature effect static mechanical properties failure properties
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Combined effects of temperature and copper ion concentration on the superoxide dismutase activity in Crassostrea ariakensis 被引量:2
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作者 WANG Hui YANG Hongshuai +2 位作者 LIU Jiahui LI Yanhong LIU Zhigang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第4期51-57,共7页
Superoxide dismutase(SOD) is a crucial antioxidant enzyme playing the first defense line in antioxidant pathways against reactive oxygen species in various organisms including marine invertebrates. There exist mainl... Superoxide dismutase(SOD) is a crucial antioxidant enzyme playing the first defense line in antioxidant pathways against reactive oxygen species in various organisms including marine invertebrates. There exist mainly two specific forms, Cu/Zn-SOD(SOD1) and Mn-SOD(SOD2), in eukaryotes. SODs are known to be concurrently modulated by a variety of environmental stressors. By using central composite experimental design and response surface method, the joint effects of water temperature(18–34°C) and copper ion concentration(0.1–1.5 mg/L) on the total SOD activity in the digestive gland of Crassostrea ariakensis were studied. The results showed that the linear effect of temperature was highly significant(P〈0.01), the quadratic effect of temperature was significant(P〈0.05); the linear effect of copper ion concentration was not significant(P〉0.05), while the quadratic effect of copper ion concentration was highly significant(P〈0.01); the interactive effect of temperature and copper ion concentration was not significant(P〉0.05); the effect of temperature was greater than that of copper ion concentration. The model equation of digestive gland SOD enzyme activity towards the two factors of interest was established, with R2 and predictive R2 as high as 0.961 6 and 0.820 7, respectively, suggesting that the goodness-offit to experimental data be very satisfactory, and could be applied to prediction of digestive gland SOD activity in C. ariakensis under the conditions of the experiment. Our results would be conducive to addressing the health of aquatic animals and/or to detecting environmental problems by taking SOD as a potential bioindicator. 展开更多
关键词 Crassostrea ariakensis superoxide dismutase temperature copper ion concentration combined effect
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The effect of high-temperature annealing on LaFe_(11.5)Si_(1.5) and the magneto-caloric properties of La_(1-x)Ce_xFe_(11.5)Si_(1.5) compounds 被引量:7
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作者 CHEN Xiang CHEN Yungui TANG Yongbo 《Rare Metals》 SCIE EI CAS CSCD 2011年第4期343-347,共5页
The powder X-ray diffraction patterns of LaFell.sSil.5 compounds annealed at different high temperatures from 1323 K (5 h) to 1623 K (2 h) show that a large amount of 1:13 phase begins to form in LaFell.sSiL5 com... The powder X-ray diffraction patterns of LaFell.sSil.5 compounds annealed at different high temperatures from 1323 K (5 h) to 1623 K (2 h) show that a large amount of 1:13 phase begins to form in LaFell.sSiL5 compound annealed at 1423 K (5 h). In the temperature range from 1423 to 1523 K, ^-Fe and LaFeSi phases rapidly decrease to form 1:13 phase. LaFeSi phase is rarely observed, and the most amount of 1:13 phase is obtained in the compound annealed at 1523 K (5 h). With the annealing temperature increasing to 1573 and 1623 K, LaFeSi is detected again in the LaFell.sSil.s compound. According to the results of annealing at different high-temperatures, the Lal-xCexFelt.sSit.5 compounds are annealed at high temperatures of 1373 K (2 h) + 1523 K (5 h). The main phase is NaZn13-type phase, and the impurity is a small amount of et-Fe in Lal-xCexFexx.sSil.5 compounds with 0 〈 x 〈 0.35, and there is a large amount of CeaFe17 phase in Lao.sCeo.sFela.sSil.s. It indicates that the substitution of cerium atoms for La in LaFelLsSil.5 compounds has limit. At the same time, the substitution of Ce for La has large effect on magnetocaloric properties. With increasing Ce content from x = 0 to x = 0.35, the Curie temperature decreases linearly from 196 to 168 K, the magnetic entropy change increases from 16.5 to 57.3 J-kg-kK-1 in a low magnetic field change of 0-2 T, and the thermal hysteresis also increases from 3 K to 8 K. 展开更多
关键词 rare earth compounds high-temperature annealing magnetocaloric effect phase composition
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Effect of La_2O_3 on microstructure and high-temperature wear property of hot-press sintering FeAl intermetallic compound 被引量:3
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作者 马兴伟 金洙吉 +1 位作者 闫石 徐久军 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第6期1031-1036,共6页
FeAl intermetallic compound with different contents of rare earth oxide La2O3 addition was prepared by hot pressing the mechanically alloyed powders.Effect of La2O3 on microstructure and high-temperature wear property... FeAl intermetallic compound with different contents of rare earth oxide La2O3 addition was prepared by hot pressing the mechanically alloyed powders.Effect of La2O3 on microstructure and high-temperature wear property of the sintered FeAl samples was investigated in this paper.The results showed that 1 wt.% La2O3 addition could refine the microstructure and increase the density of the FeAl intermetallic compound,and correspondingly improved the high-temperature wear resistance.SEM and EDS analyses of the wo... 展开更多
关键词 FEAL LA2O3 hot-press sintering high-temperature wear resistance local melting combined with oxidation rare earths
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Combined effects of water temperature and copper ion concentration on catalase activity in Crassostrea ariakensis
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作者 王辉 杨洪帅 +2 位作者 刘加慧 李艳红 刘志刚 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第4期905-912,共8页
A central composite experimental design and response surface method were used to investigate the combined effects of water temperature(18–34℃) and copper ion concentration(0.1–1.5 mg/L) on the catalase(CAT) activit... A central composite experimental design and response surface method were used to investigate the combined effects of water temperature(18–34℃) and copper ion concentration(0.1–1.5 mg/L) on the catalase(CAT) activity in the digestive gland of C rassostrea ariakensis. The results showed that the linear effects of temperature were significant(P <0.01), the quadratic effects of temperature were significant( P <0.05), the linear effects of copper ion concentration were not significant(P >0.05), and the quadratic effects of copper ion concentration were significant(P <0.05). Additionally, the synergistic effects of temperature and copper ion concentration were not significant(P >0.05), and the effect of temperature was greater than that of copper ion concentration. A model equation of CAT enzyme activity in the digestive gland of C. ariakensis toward the two factors of interest was established, with R 2, Adj. R 2 and Pred. R 2 values as high as 0.943 7, 0.887 3 and 0.838 5, respectively. These findings suggested that the goodness of fit to experimental data and predictive capability of the model were satisfactory, and could be practically applied for prediction under the conditions of the study. Overall, the results suggest that the simultaneous variation of temperature and copper ion concentration alters the activity of the antioxidant enzyme CAT by modulating active oxygen species metabolism, which may be utilized as a biomarker to detect the effects of copper pollution. 展开更多
关键词 Crassostrea ariakensis CATALASE temperature copper ion concentration combined effects
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Real world effectiveness of PCSK-9 inhibitors combined with statins versus statins-based therapy among patients with very high risk of atherosclerotic cardiovascular disease in China(RWE-PCSK study) 被引量:7
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作者 Yu-Qi LIU Dan-Dan LI +32 位作者 Meng CHAI Hong-Liang CONG Xiao-Qiang CONG Jun DAI Rong-Pin DU Ming GAO Jin-Cheng GUO Yan-Qing GUO Xiao-Jian HONG Rong-Chong HUANG Feng-Shun JIA Jia-Yu LI Qing LI Jia-Mei LIU Xin-Ping LIU Yu-Guo LIU Hong-Gang NIE Bing SHAO Xiao-Yu SHEN Hai-Qing SONG Yi-Jun SONG Li-Jun WANG Shuo WANG Dong-Mei WU Jing XIA Zhi-Yong YANG Hong-Ying YU Hui ZHANG Tie-Mei ZHANG Ji-Yi ZHAO Liang-Chen ZHAO Ming-Qi ZHENG Yun-Dai CHEN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2021年第4期261-270,共10页
BACKGROUND The efficacy and safety of proprotein convertase subtilisin/kexin type 9(PCSK-9) inhibitors were confirmed by several clinical trials, but its effectiveness in routine clinical practice in China has not bee... BACKGROUND The efficacy and safety of proprotein convertase subtilisin/kexin type 9(PCSK-9) inhibitors were confirmed by several clinical trials, but its effectiveness in routine clinical practice in China has not been evaluated. This study aims to describe the real world effectiveness of PCSK-9 inhibitors combined with statins compared with statins-based therapy among patients with very high risk of atherosclerotic cardiovascular disease(ASCVD).METHODS This is a multi-center observational study, enrolled patients from 32 hospitals who underwent percutaneous coronary intervention(PCI) from January to June in 2019. There are 453 patients treated with PCSK-9 inhibitors combined with statins in PCSK-9 inhibitor group and 2,610 patients treated with statins-based lipid lowering therapies in statins-based group. The lipid control rate and incidence of major adverse cardiovascular events(MACE) over six months were compared between two groups.A propensity score-matched(PSM) analysis was used to balance two groups on confounding factors. Survival analysis using Kaplan-Meier methods was applied for MACE.RESULTS In a total of 3,063 patients, 89.91% of patients had received moderate or high-intensity statins-based therapy before PCI, but only 9.47% of patients had low-density lipoprotein cholesterol(LDL-C) levels below 1.4 mmol/L at baseline. In the PSM selected patients, LDL-C level was reduced by 42.57% in PCSK-9 inhibitor group and 30.81%(P < 0.001) in statins-based group after six months. The proportion of LDL-C ≤ 1.0 mmol/L increased from 5.29% to 29.26% in PCSK-9 inhibitor group and 0.23% to 6.11% in statins-based group, and the proportion of LDL-C ≤ 1.4 mmol/L increased from 10.36% to 47.69% in PCSK-9 inhibitor group and 2.99% to 18.43% in statins-based group(P < 0.001 for both). There was no significant difference between PCSK-9 inhibitor and statins-based treatment in reducing the risk of MACE(hazard ratio = 2.52, 95% CI: 0.49-12.97, P = 0.250).CONCLUSIONS In the real world, PCSK-9 inhibitors combined with statins could significantly reduce LDL-C levels among patients with very high risk of ASCVD in China. The long-term clinical benefits for patients received PCSK-9 inhibitor to reduce the risk of MACE is still unclear and requires further study. 展开更多
关键词 LDL RWE-PCSK study Real world effectiveness of PCSK-9 inhibitors combined with statins versus statins-based therapy among patients with very high r
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Effect of Training on Two-way Shape Memory Effect and Its Stability in a Ti-Ni-Hf High Temperature Shape Memory Alloy 被引量:1
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作者 XianglongMENG WeiCAI +2 位作者 K.T.LAU L.M.ZHOU LianchengZHAO 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第6期590-592,共3页
The Effect of the thermal cycling training under constant strain on the two-way shape memory effect (TWSME) in a Ti36l\li49Hf15 high temperature shape memory alloy (SMA) has been investigated by bending tests. The res... The Effect of the thermal cycling training under constant strain on the two-way shape memory effect (TWSME) in a Ti36l\li49Hf15 high temperature shape memory alloy (SMA) has been investigated by bending tests. The results indicated that the training procedure is beneficial to get the better TWSME. The two-way shape memory strain increases with increasing the training strain. And it decreases with increasing the training temperature. The TWSME obtained in the present alloy shows poorer stability compared with that obtained in the TiNi alloys. 展开更多
关键词 TiNiHf alloy high temperature shape memory alloy Two-way shape memory effect TRAINING
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Flow behaviour constitutive model of CuCrZr alloy and 35CrMo steel based on dynamic recrystallization softening effect under elevated temperature 被引量:2
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作者 HUANG Yuan-chun LI Ming +2 位作者 MA Cun-qiang XIAO Zheng-bing LIU Yu 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第6期1550-1562,共13页
In order to study the effect of dynamic recrystallization on the metal flow behavior during thermal deformation,the elevated temperature compression experiments of CuCrZr alloy and 35CrMo steel are carried out using G... In order to study the effect of dynamic recrystallization on the metal flow behavior during thermal deformation,the elevated temperature compression experiments of CuCrZr alloy and 35CrMo steel are carried out using Gleeble-3810 thermal simulator.It is proved that the samples underwent obvious dynamic recrystallization behavior during thermal deformation by microstructure observation of deformed specimens.The size of recrystallized grains increases as the temperature improved and the strain rate decreased.Meanwhile,the net softening rate caused by dynamic recrystallization is determined based on the stress-dislocation relationship.It can be found that the value of net softening rate increases quadratically as the Z parameter decreases,and the dynamic recrystallization net softening rate of CuCrZr alloy and 35CrMo steel are calculated to be 21.9%and 29.8%,respectively.Based on the dynamic recrystallization softening effect proposed,the novel elevated temperature flow constitutive models of two different alloys are proposed,and the related parameters are well defined and solved in detail.The predicted values of the obtained models are agreed well with the experimental values. 展开更多
关键词 CuCrZr alloy 35CrMo steel dynamic recrystallization dynamic recrystallization softening effect high temperature flow constitutive model
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Effects of High Temperature Treatment on Seed Germination of Dodonaea viscosa(L.) Jacq 被引量:1
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作者 Guangfei ZHANG Dongfang HUO +4 位作者 Boqiang HUANG Huihong ZHANG Ting YU Liyuan MENG Wenhua SU 《Agricultural Science & Technology》 CAS 2017年第1期82-86,共5页
Seeds of Dodonaea viscosa (L.) Jacq, a representative species in dry and hot valleys in Southwest China, were chosen as experimental materials. In this experiment, the D. viscosa seeds were treated at 40, 60, 80 and... Seeds of Dodonaea viscosa (L.) Jacq, a representative species in dry and hot valleys in Southwest China, were chosen as experimental materials. In this experiment, the D. viscosa seeds were treated at 40, 60, 80 and 100℃ respectively before germination to study impacts of high temperature treatment on their generation rate and to further discuss the roles of fire during the process of vegetation formation in dry and hot valley areas of China. The results show that when the temperature was higher than 40 ℃, the germination rate of D. viscosa seeds was significantly higher than that of the control group, and the heat shock effect was apparent. The germination rate was the highest when the seeds were treated at 80 ℃ for 10 min, reaching 63.00%±2.55%. There was still a significant heat shock effect on the D. viscosa seeds which were stored for one year. In comparison with the conventional method of soaking seeds in hot water, the germination rate of D. viscose seeds which were treated at high temperature before germination increased significantly. 展开更多
关键词 high temperature treatment Dodonaea viscose (L.) Jacq Germination rate Heat shock effect Vegetation restoration
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High-Temperature Stability of Mg-1Al-12Y Alloy Containing LPSO Phase and Mechanism of Its Portevin-Le Chatelier(PLC)Effect
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作者 Qian-Long Ren Shuai Yuan +3 位作者 Shi-Yu Luan Jin-Hui Wang Xiao-Wei Li Xiao-Yu Liu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2024年第6期982-998,共17页
In this study,the high-temperature stability and the generation mechanism of the Portevin-Le Chatelier(PLC)effect in solid-solution Mg-1Al-12Y alloy with different heat treatment processes were investigated by adjusti... In this study,the high-temperature stability and the generation mechanism of the Portevin-Le Chatelier(PLC)effect in solid-solution Mg-1Al-12Y alloy with different heat treatment processes were investigated by adjusting the content of long-period stacking ordered(LPSO)phases.It was found that the content of LPSO phases in the alloys differed the most after heat treatment at 530℃for 16 h and 24 h,with values of 13.56%and 3.93%respectively.Subsequently,high-temperature tensile experiments were conducted on these two alloys at temperatures of 150℃,200℃,250℃,and 300℃.The results showed that both alloys exhibited the PLC effect at temperatures ranging from 150 to 250℃.However,at a temperature 300℃,only the alloy with a greater concentration of LPSO phases exhibited the PLC effect,whereas the alloy with a lower proportion of LPSO phases did not exhibit this phenomenon.Additionally,both alloys exhibited remarkable high-temperature stability,with the alloy containing a greater percentage of LPSO phases also demonstrating superior strength.The underlying mechanism for this phenomenon lies in the exceptional high-temperature stability exhibited by the second phase within the alloy.Furthermore,the LPSO phase effectively obstructs the movement of dislocations,and it also undergoing kinking to facilitate plastic deformation of the alloy.The results indicate that the PLC effect can be suppressed by reducing dislocation pile-up at grain boundaries,which leads to a decrease in alloy plasticity but an increase in strength.The presence of the PLC effect in the WA121 alloy is attributed to the abundant dispersed second phase within the alloy,which initially hinders the movement of dislocations,leading to an increase in stress,and subsequently releases the dislocations,allowing them to continue their movement and thereby reducing in stress. 展开更多
关键词 Magnesium alloy Long-period stacking ordered(LPSO)phase Portevin-Le Chatelier effect high temperature
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Pitting corrosion and crevice corrosion behaviors of high nitrogen austenitic stainless steels 被引量:16
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作者 Hua-bing Li Zhou-hua Jiang Yan Yang Yang Cao Zu-rui Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2009年第5期517-524,共8页
Pitting corrosion and crevice corrosion behaviors of high nitrogen austenitic stainless steels (HNSS) were investigated by electrochemical and immersion testing methods in chloride solution, respectively. The chemic... Pitting corrosion and crevice corrosion behaviors of high nitrogen austenitic stainless steels (HNSS) were investigated by electrochemical and immersion testing methods in chloride solution, respectively. The chemical constitution and composition in the depth of passive films formed on HNSS were analyzed by X-ray photoelectron spectrum (XPS). HNSS has excellent pitting and crevice corrosion resistance compared to 316L stainless steel. With increasing the nitrogen content in steels, pitting potentials and critical pitting temperature (CPT) increase, and the maximum, average pit depths and average weight loss decrease. The CPT of HNSS is correlated with the alloying element content through the measure of alloying for resistance to corrosion (MARC). The MARC can be expressed as an equation of CPT=2.55MARC-29. XPS results show that HNSS exhibiting excellent corrosion resistance is attributed to the enrichment of nitrogen on the surface of passive films, which forms ammonium ions increasing the local pH value and facilitating repassivation, and the synergistic effects of molybdenum and nitrogen. 展开更多
关键词 high nitrogen austenitic stainless steel pitting corrosion crevice corrosion NITROGEN critical pitting temperature syner-gistic effect
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Properties of failure mode and thermal damage for limestone at high temperature 被引量:13
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作者 MAO Xian-biao ZHANG Lian-ying +1 位作者 LI Tian-zhen LIU Hai-shun 《Mining Science and Technology》 EI CAS 2009年第3期290-294,共5页
The mechanical properties of limestone such as the stress-strain curve, the variable characteristics of peak strength and the modulus of elasticity of limestone were studied under the action of temperatures ranging fr... The mechanical properties of limestone such as the stress-strain curve, the variable characteristics of peak strength and the modulus of elasticity of limestone were studied under the action of temperatures ranging from room temperature to 800 °C.Our results show that:1) the temperature has not clear effect on the mechanical properties of limestone from room temperature to 600 °C.However, the mechanical properties of limestone deteriorate rapidly when the temperature is above 600 °C.In this case, the peak stress and modulus of elasticity decrease rapidly.When the temperature reaches 800 °C, the entire process, showing the stress-strain curve is displayed indicating an obvious state of plastic-deformation;2) the failure mode of limestone shows the breakdown of tensile strength from room temperature to 600 °C, as well as the compress shearing damage over 600 °C;3) combining our test results with the concept of thermal damage, a thermal damage equation was derived. 展开更多
关键词 LIMESTONE high temperature effect mech-anical properties clamage
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High Temperature Oxidation Behavior of NiCrAlY Coating by Arc Ion Plating 被引量:3
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作者 王冰 汪爱英 +2 位作者 孙超 黄荣芳 闻立时 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2001年第2期106-111,共6页
A NiCrAlY coating was prepared on the cast Ni-base superalloy K17 using arc ion plating. The coating was uniform, dense and well adhesive to the substrate. The oxidation kinetic curves of the alloy K17 and the coating... A NiCrAlY coating was prepared on the cast Ni-base superalloy K17 using arc ion plating. The coating was uniform, dense and well adhesive to the substrate. The oxidation kinetic curves of the alloy K17 and the coating were obtained. The results indicated that the oxidation resistance of the alloy K17 was evidently improved with NiCrAlY coatings at 900∼1100°C. As oxidation temperature rising, the interdiffusion between the coatings and substrates was enhanced. Ti atoms diffused from the substrate to the surface of coating to form the oxide, which was one of the reasons for the decrement of oxidation resistance. The oxidation resistance of NiCrAlY coating was decreased due to the spalling of pieces of oxide. 展开更多
关键词 high temperature effects Interdiffusion (solids) Nickel alloys Oxidation PLATING SUBSTRATES TITANIUM
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Silicon carbide resonant tuning fork for microsensing applications in high-temperature and high G-shock environments 被引量:6
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作者 David R Myers Kan Bun Cheng +6 位作者 Babak Jamshidi Robert G Azevedo Debbie G Senesky Li Chen Mehran Mehregany Muthu B J Wijesundara Albert P Pisano 《Engineering Sciences》 EI 2012年第5期36-41,共6页
We present the fabrication and testing of a silicon carbide (SiC) balanced mass doublended tuning fork that survives harsh environments without compromising the device strain sensitivity and resolution bandwidth. Th... We present the fabrication and testing of a silicon carbide (SiC) balanced mass doublended tuning fork that survives harsh environments without compromising the device strain sensitivity and resolution bandwidth. The device features a material stack that survives corrosive environments and enables high-temperature operation. To perform hightemperature testing, a specialized setup was constructed that allows the tuning fork to be characterized using traditional silicon electronics. The tuning fork has been operated at 600°C in the presence of dry steam for short durations. This tuning fork has also been tested to 64 000 G using a hard-launch, soft-catch shock implemented with a light gas gun. However, the device still has a strain sensitivity of 66 Hz/μe and strain resolution of 0. 045 μe in a 10 kHz bandwidth. As such, this balanced-mass double-ended tuning fork can be used to create a variety of different sensors including strain gauges, accelerometers, gyroscopes, and pressure transducers. Given the adaptable fabrication process flow, this device could be useful to micro-electro-mechanical systems (MEMS) designers creating sensors for a variety of different applications. 展开更多
关键词 MEMS SiC thermal effects double ended tuning fork (DETF) harsh environment high temperature high shock INERTIAL STRAIN sensors
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