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First-Principles Calculations about Elastic and Li^(+) Transport Properties of Lithium Superoxides under High Pressure and High Temperature
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作者 李玉峰 孙士川 +1 位作者 何宇 李和平 《Chinese Physics Letters》 SCIE EI CAS CSCD 2022年第2期47-52,共6页
Lithium superoxides,Li_(2)O_(3),LiO_(2),and LiO_(4),have been synthesized under high pressure.These materials have potential applications in energy storage devices.Here,we use first-principles calculations to investig... Lithium superoxides,Li_(2)O_(3),LiO_(2),and LiO_(4),have been synthesized under high pressure.These materials have potential applications in energy storage devices.Here,we use first-principles calculations to investigate the elastic and Li^(+) transport properties of these oxides at high pressure and high temperature.The elastic constants are calculated at 20-80 GPa,and they satisfy the Born stability criteria,indicating the good mechanical stability of these oxides.Their sound velocities calculated with elastic constants are close to each other,but difference in velocity anisotropy is obvious.LiO_(2) presents significant shear sound wave anisotropy over 80%.The Li^(+) transport properties are investigated using first principles molecular dynamics(FPMD)and climbing-image nudged elastic band methods.The lowest Li^(+) migration barrier energies increase from 0.93,0.86 and 1.22 eV at 20 GPa to 1.43,1.12 and 1.77 eV at 50 GPa for Li_(2)O_(3),LiO_(2),and LiO_(4),respectively.The most favorable path for LiO_(2) and LiO_(4) is along the[001]direction.The FPMD results suggest that these oxides become unstable with increasing temperature up to 2000 K due to O-O dimer clusters in these superoxides.Consequently,a superionic transition is not observed in the simulations. 展开更多
关键词 temperature ANISOTROPY LITHIUM
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Study on Response Surface Methodology Optimization for Extraction Process of Cyclocarya paliurus Extract and Its Blood Sugar-lowering Effect
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作者 yufeng li Xiayun liAO +1 位作者 Gang WANG lichun ZHAO 《Agricultural Biotechnology》 CAS 2020年第5期127-133,共7页
[Objectives]This study was conducted to discuss the mechanism of the blood sugar-lowering effect of Cyclocarya paliurus extract.[Methods]With C.paliurus leaves as the raw material,the ethyl acetate-butyl acetate micro... [Objectives]This study was conducted to discuss the mechanism of the blood sugar-lowering effect of Cyclocarya paliurus extract.[Methods]With C.paliurus leaves as the raw material,the ethyl acetate-butyl acetate microwave extraction process of C.paliurus was studied.With the yield of C.paliurus extract as an evaluation index,single-factor experiments were carried out on such 6 factors as the dry C.paliurus leaf powder size,solid-to-liquid ratio,extraction time,microwave frequency,microwave power,and microwave extraction time,and the extraction and purification process was further optimized by response surface analysis.The normal mice and the hyperglycemic mice modeled by alloxan were injected with C.paliurus extract to study the blood sugar-lowering effects of different groups of C.paliurus extract.[Results]The optimal process combination for the extraction of C.paliurus leaves was obtained:dry C.paliurus powder size 90-100 mesh,solid-to-liquid ratio 1∶20(g/ml),extraction time 192 min,microwave frequency 2500 MHz,microwave power 490 W,and extraction time 248 s.Under these conditions,the yield of C.paliurus extract reached the maximum,95.10%,reaching 99.83%of the predicted value.The blood sugar-lowering test on mice showed that the C.paliurus extract had a good effect on lowering blood sugar,indicating that C.paliurus extract can improve the free radical scavenging capacity to a certain extent.[Conclusions]This study provides certain reference for the in-depth study of the physiological effects of C.paliurus extract and the comprehensive development and utilization of C.paliurus extract. 展开更多
关键词 Cyclocarya paliurus C.paliurus extract YIELD Blood sugar lowering Radical scavenging
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二次掺杂制备聚苯胺/石墨烯/碳纳米管复合材料及其防腐性能 被引量:1
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作者 李昱锋 孔明洁 +1 位作者 李斌 杨小刚 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第8期81-90,共10页
在高氯酸体系中通过原位聚合将苯胺(ANI)单体分别与还原氧化石墨烯(RGO)、碳纳米管(CNTs)制备了一次掺杂态产物PANI/RGO和PANI/CNTs,产物分别经氨水解掺杂后,在高氯酸体系中经二次掺杂制备得到二次掺杂态聚苯胺/石墨烯/碳纳米管(Redoped... 在高氯酸体系中通过原位聚合将苯胺(ANI)单体分别与还原氧化石墨烯(RGO)、碳纳米管(CNTs)制备了一次掺杂态产物PANI/RGO和PANI/CNTs,产物分别经氨水解掺杂后,在高氯酸体系中经二次掺杂制备得到二次掺杂态聚苯胺/石墨烯/碳纳米管(Redoped PANI/RGO/CNTs)复合材料。通过扫描电镜、透射电镜、傅里叶变换红外光谱和紫外光谱对其不同产物形貌和结构进行表征,通过电化学工作站测试了不同产物在3.5%NaCl溶液的防腐蚀性能。结果表明,在RGO与ANI质量比为1:20、CNTs与ANI质量比为1:20时,二次掺杂态产物中聚苯胺纳米纤维可分别在RGO和CNTs上均匀生长并形成网状结构,纤维长度达到850 nm,形貌均一,其防腐蚀性能最优异,缓蚀效率可达81.79%。通过二次掺杂将PANI/RGO和PANI/CNTs复合制备Redoped PANI/RGO/CNTs材料,可有效避免石墨烯和碳纳米管在制备复合材料过程中的团聚,得到结构规整、防腐性能更优异的复合材料。 展开更多
关键词 高氯酸 还原氧化石墨烯 碳纳米管 聚苯胺 电化学 掺杂
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Regeneration and anti-migration of sand waves associated with sand mining in the Taiwan Shoal
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作者 Jingjing Bao Feng Cai +6 位作者 Chengqiang Wu Huiquan Lu Yongling Zheng yufeng li li Sun Chungeng liu Yongbao li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第9期71-78,共8页
Sand waves in the Taiwan Shoal are characterized by two distinct spatial scales. Giant sand waves have a length of2 kilometers with height between 5 m and 25 m, whilst small sand waves is less than 100-m long with hei... Sand waves in the Taiwan Shoal are characterized by two distinct spatial scales. Giant sand waves have a length of2 kilometers with height between 5 m and 25 m, whilst small sand waves is less than 100-m long with height less than 5 m between giant sand wave peaks(crests). A series of five high-resolution multi-beam echo-sounding surveys between 2012 and 2020 in the middle of Taiwan Shoal indicated that artificial dredging on the giant sand waves had caused sand wave reform and evolution. Overall, the removal of giant sand waves significantly affected the migration of small sand waves adjacent to the dredging site, with the latter on both sides of the former appear to migrate towards the dredging pit. Moreover, in the dredging area, new sand waves emerged with wavelength much smaller than the original giant sand waves, while the convergent pattern of the small sand waves tends to store and form the giant sand waves, which might spread far beyond the survey period. 展开更多
关键词 small sand wave giant sand wave anti-migration regrowing sand mining Taiwan Shoal
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Differences of polygonal faults related to upper Miocene channels:a case study from the Beijiao sag of Qiongdongnan basin,South China Sea
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作者 yufeng li Renhai PU +4 位作者 Xueqin ZHAO Gongcheng ZHANG Xiaowei FAN Jingjing BAO Jiong WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第1期84-99,共16页
Deep-water coarse-grained channels are embedded within a polygonal fault tier,and the polygonal faults(PFs)present non-polygonal geometries rather than classic polygonal geometry in plan view.However,PFs present diffe... Deep-water coarse-grained channels are embedded within a polygonal fault tier,and the polygonal faults(PFs)present non-polygonal geometries rather than classic polygonal geometry in plan view.However,PFs present differences when they encounter deep-water(coarse-grained vs.fine-grained)channels with different lithology,which has not been further studied to date.Three-dimensional(3D)seismic data and a drilling well from Beijiao sag of Qiongdongnanbasin,South China Sea were utilized to document the plan view and cross-sectional properties of the PFs and their differences and genetic mechanism were investigated.Results show that,first,PFs can be divided morphologically into channel-segmenting PFs and channel-bounding PFs in plan view.The former virtually cuts or segments the axes of channels in highand low-amplitudes,and the latter nearly parallels the boundaries of the channels.Both are approximately perpendicular to each other.Secondly,channel-bounding PFs that related to low-amplitude channels are much longer than those of high-amplitude ones;channel-segmenting PFs related to low-amplitude channels are slightly longer than the counterparts related to high-amplitude channels.Lastly,the magnitudes(e.g.,heights)of the PFs are proportional to the scales(e.g.,widths and heights)of low-amplitude channels,whereas the magnitudes of the PFs are inversely proportional to the scales of high amplitude channels.Coarse-grained(high amplitude)channels act as a mechanical barrier to the propagation of PFs,whereas fine-grained(low-amplitude)channels are beneficial to the propagation and nucleation of PFs.Additionally,the genetic mechanism of PFs is discussed and reckoned as combined geneses of gravitational spreading and overpressure hydrofracture.The differences of the PFs can be used to reasonably differentiate coarse-grained channels from fine-grained channels.This study provides new insights into understanding the different geometries of the PFs related to coarse-grained and fine-grained channels and their genetic mechanism. 展开更多
关键词 polygonal faults coarse-grained channels fine-grained channels gravitational spreading overpressure hydrofracture
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Optimal geometrical configuration and oxidation state of cobalt cations in spinel oxides to promote the performance of Li-O_(2) battery
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作者 Yu Zhang Shuting Zhang +4 位作者 Mengwei Yuan yufeng li Rong liu Caiyun Nan Chen Chen 《Nano Research》 SCIE EI CSCD 2024年第1期221-227,共7页
Co_(3)O_(4) is considered as one of promising cathode catalysts for lithium oxygen(Li-O_(2))batteries,which contains both tetrahedral Co^(2+)sites(Co^(2+)Td)and octahedral Co^(3+)sites(Co^(3+)Oh).It is important to re... Co_(3)O_(4) is considered as one of promising cathode catalysts for lithium oxygen(Li-O_(2))batteries,which contains both tetrahedral Co^(2+)sites(Co^(2+)Td)and octahedral Co^(3+)sites(Co^(3+)Oh).It is important to reveal the effect of optimal geometric configuration and oxidation state of cobalt ion in Co_(3)O_(4) to improve the performance of Li-O_(2) batteries.Herein,through regulating the synthesis process,Co^(2+)and Co^(3+)sites in Co_(3)O_(4) were replaced with Zn and Al atoms to form materials with a unique Co site.The Li-O_(2) batteries based on ZnCo_(2)O_(4) showed longer cycle life than that of CoAl_(2)O_(4),suggesting that in Co_(3)O_(4),the Co^(3+)Oh site is a relatively better geometric configuration than Co^(2+)Td site for Li-O_(2) batteries.Theoretical calculations revealed that Co^(3+)Oh sites provide higher catalysis activity,regulating the adsorption energy of the intermediate LiO_(2) and accelerating the kinetics of the reaction in batteries,which further leads to the change of the morphology of the discharge product and ultimately improves the electrochemical performance of the batteries. 展开更多
关键词 lithium oxygen(Li-O_(2))batteries geometrical configuration oxidation state lithium peroxide
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Specimen Radiography for MRI-Guided Biopsies
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作者 Stefanie Woodard Elizabeth Allen +4 位作者 Renu Pandit Glenn Irby Shi Wei yufeng li Jeong Mi Park 《Open Journal of Radiology》 2021年第4期139-150,共12页
<strong>Background:</strong> Specimen radiography is important for the biopsy of breast microcalcifications, and MRI is limited in the detection of microcalcifications. It is unknown whether or not the pre... <strong>Background:</strong> Specimen radiography is important for the biopsy of breast microcalcifications, and MRI is limited in the detection of microcalcifications. It is unknown whether or not the presence of microcalcifications on MRI-guided biopsies is significant. <strong>Purpose:</strong> To determine whether specimen radiography of MRI-guided biopsy samples provides any added benefits in tissue assessment. <strong>Materials and Methods:</strong> This is an IRB-approved, HIPPA-compliant retrospective review of MRI-guided biopsy reports whose tissue underwent specimen radiography from 2010 to 2017. Pathology reports were queried to compare samples with and without calcium and reviewed to determine if calcifications correlated with the lesion of interest. If there was a correlation, the original MRI was reviewed. Final pathology reports were also reviewed if excision was performed. <strong>Results:</strong> A total of 889 patients ages 22 - 85 were included with 140 (15.7%, 140/889) containing calcifications. Of 140 specimens, 119 (85.0%, 119/140) cases separated the calcifications. A total of 41 (34.5%, 41/119) were malignant or high-risk lesions/atypia of which 15 (36.6%, 15/41) showed a higher-grade lesion in the specimen containing calcium. Out of these 15, 4 (26.7%, 4/15) were pathologically associated with calcium;however, pathologic diagnosis was not dependent on the presence of calcifications. All 4 were high-risk lesions and none were malignancies. MRI in these cases showed three enhancing masses and one non-mass enhancement. None were upgraded at excision. <strong>Conclusion:</strong> The presence of microcalcifications on MRI-guided biopsies does not aid in tissue assessment and does not impact pathologic diagnosis. Specimen radiography provides no added benefits in the setting of MRI-guided biopsies. 展开更多
关键词 MRI-Guided Breast Biopsy Specimen Radiography MICROCALCIFICATIONS High-Risk Lesion Breast Cancer UPGRADE
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Effects of massage on newborn infants with jaundice: A meta-analysis 被引量:6
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作者 Mengjie Lei Tingting liu +3 位作者 yufeng li Yaqian liu lina Meng Changde Jin 《International Journal of Nursing Sciences》 2018年第1期89-97,共9页
Objective:This meta-analysis aims to systematically evaluate the effects of massage on infants with jaundice.Methods:Multiple electronic databases,including Cochrane Library,PubMed,EMBASE,Web of Science,China Biology ... Objective:This meta-analysis aims to systematically evaluate the effects of massage on infants with jaundice.Methods:Multiple electronic databases,including Cochrane Library,PubMed,EMBASE,Web of Science,China Biology Medicine (CBM),Wan Fang Data,VIP Database for Chinese Technical Periodicals and China National Knowledge Infrastructure (CNKI),were used to search for studies on the effects of massage on infants with jaundice.Data were analysed by Rev Man 5.3.Results:A total of 14 randomised controlled trials with 1889 patients were included.Statistically significant difference in percutaneous bilirubin [MD =-1.21,95% CI (-1.90,-0.52),P< 0.05;MD =-2.00,95% CI (-2.68,-1.32),P<0.05;MD=-2.00,95% CI (2.56,-1.44),P<0.05;MD=-1.93,95% CI (-2.44,-1.43),P< 0.05] was found between two groups at 48,72,96 and 168 h.Studies on the serum total bilirubin level were divided into two subgroups according to sample size,and the results of subgroup analysis showed that the serum total bilirubin level in the intervention group was significantly lower than that in the control group [MD =-52.06,95% CI (-57.76,-46.36),P< 0.05 and MD =-10.65,95% CI (-14.66,-6.63),P < 0.05].Statistically significant difference in defecation frequency was observed between the two groups at 48 h after birth[SMD =0.44,95%CI (0.02,0.87),P< 0.05].Conclusion:Massage can decrease serum total bilirubin and percutaneous bilirubin levels and increasing defecation frequency.However,due to heterogeneity among studies,numerous multi-centre,largesample and high-quality randomised controlled trials are needed to verify the effects of massage. 展开更多
关键词 JAUNDICE MASSAGE META-ANALYSIS NEONATE
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太极运动对脑卒中患者运动功能及睡眠质量影响的系统评价 被引量:3
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作者 李玉峰 张亚静 +5 位作者 崔楚云 刘雅倩 雷梦杰 刘婷婷 孟丽娜 金昌德 《International Journal of Nursing Sciences》 2017年第3期314-321,共8页
目的系统评价太极运动对脑卒中患者运动功能和睡眠质量的效果。方法通过计算机系统检索国内外多个电子数据库:PubMed.Web of Science、Cochrane Library、EMBASE、AMED、中国生物医学文献数据库(CBM)、CNKI中国学术期刊全文数据库、万... 目的系统评价太极运动对脑卒中患者运动功能和睡眠质量的效果。方法通过计算机系统检索国内外多个电子数据库:PubMed.Web of Science、Cochrane Library、EMBASE、AMED、中国生物医学文献数据库(CBM)、CNKI中国学术期刊全文数据库、万方数据库和维普数据库,检索时限为建库起至2016年8月。两名研究者通过使用Cochrane手册推荐的随机临床对照试验(RCT)文献质量评估标准,独立筛选符合条件的研究、提取数据,并评估方法学质量。然后采用RevMan 5.3软件进行Meta分析。结果最终共纳人17项随机对照试验研究,包括1209例研究对象。Meta分析结果显示,太极运动在提高脑卒中患者的平衡功能(P<0.001)和日常活动能力(P=0.0003)方面,均优于常规对照组,差异有统计学意义;然而在步行功能和睡眠质量方面,两组差异无统计学意义(P>0.05)。结论太极运动可以显著提高脑卒中患者的平衡功能和日常活动能力,而在步行功能和睡眠质量方面差异无统计学意义。太极运动对脑卒中患者步行功能和睡眠质量的是否有改善作用尚需要进行更高质量的随机对照试验来验证。 展开更多
关键词 太极 脑卒中 运动 睡眠
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Characteristics and origins of middle Miocene mounds and channels in the northern South China Sea 被引量:1
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作者 yufeng li Gongcheng Zhang +3 位作者 Renhai Pu Hongjun Qu Huailei Shen Xueqin Zhao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第2期65-80,共16页
Numerous elongated mounds and channels were found at the top of the middle Miocene strata using 2D/3D seismic data in the Liwan Sag of Zhujiang River Mouth Basin(ZRMB)and the Beijiao Sag of Qiongdongnan Basin(QDNB).Th... Numerous elongated mounds and channels were found at the top of the middle Miocene strata using 2D/3D seismic data in the Liwan Sag of Zhujiang River Mouth Basin(ZRMB)and the Beijiao Sag of Qiongdongnan Basin(QDNB).They occur at intervals and are rarely revealed by drilling wells in the deepwater areas.Origins of the mounds and channels are controversial and poorly understood.Based on an integrated analysis of the seismic attribute,palaeotectonics and palaeogeography,and drilling well encountering a mound,research results show that these mounds are dominantly distributed on the depression centres and/or slopes of the Liwan and Beijiao sags and developed in a bathyal sedimentary environment.In the Liwan and Beijiao sags,the mounds between channels(sub)parallel to one another are 1.0–1.5 km and 1.5–2.0 km wide,150–300 m and 150–200 m high,and extend straightly from west to east for 5–15 km and 8–20 km,respectively.Mounds and channels in the Liwan Sag are parallel with the regional slope.Mounds and channels in the Beijiao Sag,however,are at a small angle to the regional slope.According to internal geometry,texture and external morphology of mounds,the mounds in Beijiao Sag are divided into weak amplitude parallel reflections(mound type I),blank or chaotic reflections(mound type II),and internal mounded reflections(mound typeⅢ).The mounds in Liwan Sag,however,have the sole type,i.e.,mound type I.Mound type I originates from the incision of bottom currents and/or gravity flows.Mound type II results from gravity-driven sediments such as turbidite.Mound typeⅢis a result of deposition and incision of bottom currents simultaneously.The channels with high amplitude between mounds in the Beijiao and Liwan sags are a result of gravity-flow sediments and it is suggested they are filled by sandstone.Whereas channels with low-mediate amplitudes are filled by bottom-current sediments only in the Beijiao Sag,where they are dominantly composed of mudstone.This study provides new insights into the origins of the mounds and channels worldwide. 展开更多
关键词 South China Sea middle Miocene channels and mounds contour currents
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Influence of Artificial Cofferdam and Spartina alterniflora Expansion on Evolution of Suaeda salsa Marsh in Yancheng Coastal Wetland of East China 被引量:1
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作者 Shuang HAN Yan ZHEN +1 位作者 yufeng li Huabing ZHANG 《Asian Agricultural Research》 2018年第4期72-76,88,共6页
Suaeda salsa is an important local species in the intertidal beach of the Western Pacific coast. However,under the artificial cofferdam and Spartina alterniflora expansion,Suaeda marsh has degraded seriously. Therefor... Suaeda salsa is an important local species in the intertidal beach of the Western Pacific coast. However,under the artificial cofferdam and Spartina alterniflora expansion,Suaeda marsh has degraded seriously. Therefore,using Yancheng Nature Reserve as a case study area,taking ETM+images in 2000,2006 and 2011 as the basic data sources,we revealed the evolution characteristics of Salsa marsh which was impacted. The research results are as follows. From 2000 to 2011,Salsa marsh area in the artificial area tempestuously degraded,decreasing by 87. 158%,more than 22% than those in the natural area. The landscape was fragmentized. Landscape polymerization degree index dropped from 95. 780 to 65. 455,more than 16% than those in the natural area. The mean patch area fell down to 21. 429 ha from 389. 333 ha,more than 11% that in the natural area. Compared to the steady change in natural conditions,the area was reduced by 118. 167 ha/a from 2000 to 2006,while during 2006-2011,it was only 51. 500 ha/a in artificial area. As for spatial change of landscape,in artificial area,the Salsa marsh centroid moved forward to the southeast with 666. 350 m,but that in natural area moved forward to the north with 1 042. 710 m from 2000 to 2006. From 2006 to 2011,the centroid moved forward to east and north respectively. Artificial cofferdam transformed the area into freshwater ecosystem,and meanwhile the freshwater was beneficial to Reed marsh. During 2000 to 2006,in the artificial area,539 ha Salsa marsh controlled by cofferdam transferred into reed marsh and aquaculture ponds,of which the transformation rate was nearly 4% higher than that in natural area. From 2006 to 2011,178 ha Salsa marsh was transferred into reed marsh,the transformation rate was 20% higher than that in natural area. With rapid spreading and strong competition of Spartina species,the coastal wetland has formed the pattern of " Salsa – Spartina marshes". From 2000 to 2006,in artificial area,15. 24% of Salsa marsh was transferred into Spartina marsh,of which the transformation rate was13% higher than that in natural area. And from 2006 to 2011,30. 07% Salsa marsh was replaced by the Spartina marsh in artificial area,the rate was almost 10% higher than that in the natural area. 展开更多
关键词 Artificial cofferdam Spartina alterniflora expansion Temporal and spatial evolution Suaeda salsa marsh Yancheng Nature Reserve
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XAFS study on interactions of metallothionein, mercuric chloride and/or sodium selenite
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作者 yufeng li Chunying CHEN +4 位作者 Jiangxue WANG Yuxi GAO Bai li Yuliang ZHAo Zhifang CHAI 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期124-124,共1页
关键词 透明石膏 金属硫蛋白 XAFS 氯化汞
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Anti-tumor Effect and Mechanism of Pratia Extract on H22 Tumor-bearing Mice
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作者 lichun ZHAO yufeng li +1 位作者 Wenxue ZHU Wei li 《Agricultural Biotechnology》 CAS 2019年第4期78-80,共3页
[Objectives]This study was conducted to investigate the inhibitory effect of pratia extract on H22 tumor-bearing mice and the effects on immune organs.[Methods]With the application of H22 liver tumor-bearing mice as a... [Objectives]This study was conducted to investigate the inhibitory effect of pratia extract on H22 tumor-bearing mice and the effects on immune organs.[Methods]With the application of H22 liver tumor-bearing mice as an animal model,the animals were divided into such three Pratia extract groups as the high,medium and low dose groups(400,200 and 100 mg/kg)and cyclophosphamide CTX group(20 mg/kg).15 d after the administration,the animals were killed by cervical dislocation,and the tumors,thymuses and spleens were taken and weighed,followed by the calculation of the tumor inhibitory rate and the thymus and spleen index,and the serum tumor necrosis factor-α(TNF-α)and interleukin-2(IL-2)levels were determined by ELISA assay.[Results]The inhibitory rates were 54.1,32.6 and 8.2%,respectively,and there were significant differences from the model group(P<0.05);and the spleen index of the tumor-bearing mice was reduced,while the thymus index was improved.The serological results showed that the drug-administrated groups significantly improved the IL-2 levels in the tumor-bearing mice,but had no effects on TNF-α.[Conclusions]Pratia extract has an antitumor effect on H22 tumor-bearing mice,and show certain dose-effect relationship,and its mechanism may be related to enhancing the immune function in tumor-bearing mice by regulating IL-2. 展开更多
关键词 Pratia H22 Tumor-bearing MICE TNF-α IL-2
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Research on Channel Codec of DCR System Based on CMX7141
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作者 yufeng li Jun Yang Qingyang Guan 《Communications and Network》 2013年第3期286-291,共6页
This article introduces a digital private network of mobile communication dedicated chipset CMX7141 that used for the 4FSK modulation and demodulation in DCR system, and introduces the application of CMX7141 inthe DCR... This article introduces a digital private network of mobile communication dedicated chipset CMX7141 that used for the 4FSK modulation and demodulation in DCR system, and introduces the application of CMX7141 inthe DCR system. Focus research on the channel codec techniques of the chip and have a simulation on the channel coding and decoding. The simulation results indicate that, through channel error correction technique in CMX7141, the BER of DCR system reduces greatly and the transmission quality of DCR system is improved. 展开更多
关键词 DCR CMX7141 CYCLIC REDUNDANCY CHECK Punctured Convolutional CODING
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Hybridoma-derived neutralizing monoclonal antibodies against Beta and Delta variants of SARS-CoV-2 in vivo
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作者 Qianran Wang Lu Peng +16 位作者 Yanqiu Nie Yanni Shu Huajun Zhang Zidan Song yufeng li Hengrui Hu liushuai li Xi Wang Jia liu Jiang li Zhengli Shi Fei Deng Yu Guo Yiwu Zhou Bing Yan Zhihong Hu Manli Wang 《Virologica Sinica》 SCIE CAS CSCD 2023年第2期257-267,共11页
Neutralizing monoclonal antibodies(mAb)are a major therapeutic strategy for the treatment of severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection.The continuous emergence of new SARS-CoV-2 variants wor... Neutralizing monoclonal antibodies(mAb)are a major therapeutic strategy for the treatment of severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection.The continuous emergence of new SARS-CoV-2 variants worldwide has increased the urgency for the development of new mAbs.In this study,we immunized mice with the receptor-binding domain(RBD)of the SARS-CoV-2 prototypic strain(WIV04)and screened 35 RBDspecific mAbs using hybridoma technology.Results of the plaque reduction neutralization test showed that 25 of the mAbs neutralized authentic WIV04 strain infection.The 25 mAbs were divided into three categories based on the competitive enzyme-linked immunosorbent assay results.A representative mAb was selected from each category(RD4,RD10,and RD14)to determine the binding kinetics and median inhibitory concentration(IC_(50))of WIV04 and two variants of concern(VOC):B.1.351(Beta)and B.1.617.2(Delta).RD4 neutralized the B.1.617.2 variant with an IC50 of 2.67 ng/mL;however,it completely lost neutralizing activity against the B.1.351 variant.RD10 neutralized both variants with an IC50 exceeding 100 ng/mL;whereas RD14 neutralized two variants with a higher IC50(>1 mg/mL).Animal experiments were performed to evaluate the protective effects of RD4 and RD10 against various VOC infections.RD4 could protect Adv-hACE2 transduced mice from B.1.617.2 infection at an antibody concentration of 25 mg/kg,while RD10 could protect mice from B.1.351 infection at an antibody concentration of 75 mg/kg.These results highlight the potential for future modifications of the mAbs for practical use. 展开更多
关键词 COVID-19 SARS-CoV-2 B.1.351 B.1.617.2 Monoclonal antibody
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Entropy engineering design of high-performing lithiated oxide cathodes for proton-conducting solid oxide fuel cells
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作者 yufeng li Yangsen Xu +3 位作者 Yanru Yin Hailu Dai Yueyuan Gu Lei Bi 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2023年第11期2017-2031,共15页
A new medium entropy material LiCo_(0.25)Fe_(0.25)Mn_(0.2)5Ni_(0.2)5O_(2)(LCFMN)is proposed as a cathode for proton-conducting solid oxide fuel cells(H-SOFCs).Unlike traditional LiXO_(2)(X=Co,Fe,Mn,Ni)lithiated oxides... A new medium entropy material LiCo_(0.25)Fe_(0.25)Mn_(0.2)5Ni_(0.2)5O_(2)(LCFMN)is proposed as a cathode for proton-conducting solid oxide fuel cells(H-SOFCs).Unlike traditional LiXO_(2)(X=Co,Fe,Mn,Ni)lithiated oxides,which have issues like phase impurity,poor chemical compatibility,or poor fuel cell performance,the new LCFMN material mitigates these problems,allowing for the successful preparation of pure phase LCFMN with good chemical and thermal compatibility to the electrolyte.Furthermore,the entropy engineering strategy is found to weaken the covalence bond between the metal and oxygen in the LCFMN lattice,favoring the creation of oxygen vacancies and increasing cathode activity.As a result,the H-SOFC with the LCFMN cathode achieves an unprecedented fuel cell output of 1803 mW·cm^(−2)at 700℃,the highest ever reported for H-SOFCs with lithiated oxide cathodes.In addition to high fuel cell performance,the LCFMN cathode permits stable fuel cell operation for more than 450 h without visible degradation,demonstrating that LCFMN is a suitable cathode choice for H-SOFCs that combining high performance and good stability. 展开更多
关键词 entropy design LiCo_(0.25)Fe_(0.25)Mn_(0.25)Ni_(0.25)O_(2)(LCFMN) CATHODE proton conductor solid oxide fuel cells(SOFCs)
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Oxidative stress in granulosa cells contributes to poor oocytequality and IVF-ET outcomes in women with polycystic ovarysyndrome 被引量:26
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作者 Qiaohong Lai Wenpei Xiang +5 位作者 Qing li Hanwang Zhang yufeng li Guijin Zhu Chengliang Xiong Lei Jin 《Frontiers of Medicine》 SCIE CAS CSCD 2018年第5期518-524,共7页
The increased levels of intraceHular reactive oxygen species (ROS) in granulosa cells (GCs) may allectthe pregnancy results in women with polycystic ovary syndrome (PCOS). In this study, we compared the in vitro... The increased levels of intraceHular reactive oxygen species (ROS) in granulosa cells (GCs) may allectthe pregnancy results in women with polycystic ovary syndrome (PCOS). In this study, we compared the in vitrofertilization and embryo transfer (IVF-ET) results of 22 patients with PCOS and 25 patients with tubal factorinfertility and detected the ROS levels in the GCs of these two groups. Results showed that the PCOS group hadsignificantly larger follicles on the administration day for human chorionic gonadotropin than the tubal factorgroup (P 〈 0.05); however, the number of retrieved oocytes was not significantly different between the two groups(P 〉 0.05). PCOS group had slightly lower fertilization, cleavage, grade IflI embryo, clinical pregnancy, andimplantation rates and higher miscarriage rate than the tubal factor group (P 〉 0.05). We further found asignificantly higher ROS level of GCs in the PCOS group than in the tubal factor group (P 〈 0.05). The increasedROS levels in GCs caused GC apoptosis, whereas NADPH oxidase 2 (NOX2) specific inhibitors (diphenyleneio-donium and apocynin) significantly reduced the ROS production in the PCOS group. In conclusion, the increasedROS expression levels in PCOS GCs greatly induced cell apoptosis, which further affected the oocyte quality andreduced the positive IVF-ET pregnancy results of women with PCOS. NADPH oxidase pathway may be involvedin the mechanism of ROS production in GCs of women with PCOS. 展开更多
关键词 PCOS ROS GRANULOSA cell IVF-ET NADPH OXIDASE
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Ordered two-dimensional porous Co3O4 nanosheets as electrocatalysts for rechargeable Li-O2 batteries 被引量:3
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作者 Yu Zhang Mingzhen Hu +6 位作者 Mengwei Yuan Genban Sun yufeng li Kebin Zhou Chen Chen Caiyun Nan Yadong li 《Nano Research》 SCIE EI CAS CSCD 2019年第2期299-302,共4页
Lithium-oxygen batteries have attracted considerable interest in the past a few years, because they have higher theoretical specific energy than Li-ion batteries. However, the available en ergy den sities of the Li-O2... Lithium-oxygen batteries have attracted considerable interest in the past a few years, because they have higher theoretical specific energy than Li-ion batteries. However, the available en ergy den sities of the Li-O2 batteries are much less than expected. It is particularly urgent to find catalyst with high activity. Herein, a series of Co3O4 with differe nt morphologies (ordered two-dimensio nal porous nano sheets, flowerlike and cuboidlike) were successfully prepared through facile hydrothermal and calcinatio n methods. Ordered two-dime nsional Co3O4 nano sheets show the best cycling stability. Detailed experimental results reveal that the superiority of the unique two-dimensional uniform porous structures is vital for Li-O2 batteries cathode catalysts. Due to the ordered structures with high surface areas and active sites, the catalysts indicate a high specific discharge capacity of about 10,417 mAh/g at a current density of 200 mA/g, and steadily cycle for more than 50 times with a limited capacity of 1,000 mAh/g. 展开更多
关键词 Li-O2 battery ORDERED TWO-DIMENSIONAL POROUS CO3O4
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Unsteady Numerical Simulation of Steam-Solid Two-Phase Flow in the Governing Stage of a Steam Turbine 被引量:2
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作者 yufeng li Peigang Yan Wanjin Han 《Journal of Thermal Science》 SCIE EI CAS CSCD 2009年第4期313-320,共8页
Solid particle erosion (SPE) in an ultra-supercritical steam turbine control stage with block configuration is investigatednumerically, based on the finite volume method and the fluid-particle coupling solver. We appl... Solid particle erosion (SPE) in an ultra-supercritical steam turbine control stage with block configuration is investigatednumerically, based on the finite volume method and the fluid-particle coupling solver. We apply the particlediscrete phase model to model the solid particles flow, and use the Euler conservation equations to solve thecontinuous phase. The investigation is focused on the influence of the solid particle parameters (such as particlediameter, particle velocity and particle trajectory) on the erosion rate of the stator and rotor blade surface in unsteadycondition. The distributions of the highly eroded zone on the stator and rotor blade surfaces are shown anddiscussed in detail according to the mechanism of solid particle/blade wall interaction. We obtain that the erosionrate of the vane blade is sensitive to the fluctuation of the potential flow field, and the smaller particle has agreater impact on the erosion distribution of rotor blade. The erosion rate does not entirely depend on the diametersize of the solid particle. 展开更多
关键词 超临界汽轮机 非定常数值模拟 固体颗粒侵蚀 调节级 两相流 离散相模型 叶片表面 粒子轨迹
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