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Toldt’s间隙的CT影像解剖学观察及临床意义 被引量:1
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作者 欧阳满照 陈小伍 +5 位作者 丁自海 朱达坚 剧永乐 伍锦浩 陆光生 李泳 《中国临床解剖学杂志》 CSCD 北大核心 2013年第2期161-164,共4页
目的术前通过CT影像识别Toldt’s间隙,为腹腔镜结直肠癌手术寻找正确的外科平面,从而制订具有前瞻眭的个性化术式。方法通过对南方医科大学附属顺德第一人民医院2010年1月-2012年6月246例腹腔镜结直肠癌手术患者的术前CT影像及术中镜... 目的术前通过CT影像识别Toldt’s间隙,为腹腔镜结直肠癌手术寻找正确的外科平面,从而制订具有前瞻眭的个性化术式。方法通过对南方医科大学附属顺德第一人民医院2010年1月-2012年6月246例腹腔镜结直肠癌手术患者的术前CT影像及术中镜下所见对照观察,确认Toldt’s间隙的位置、沟通和毗邻关系。结果术前CT影像观察到:升降结肠系膜后叶与。肾前筋膜融合成的线影即为Toldt’s线。结直肠癌术前cT所显示的Toldt’s筋膜间隙与术中所见具有较好的一致性(Kappa值为0.718)。腹腔镜结直肠癌手术时沿此线切开,以肾前筋膜为参照面,即可建立正确的外科平面。结论①术前CT影像可指导术中构建正确的Toldt’s间隙外科平面,保持肾前筋膜的完整性;②CT可提示肿瘤是否侵犯Toldt’s间隙平面,对于制订个性化术式和预后评估具有前瞻性意义。 展开更多
关键词 腹腔镜 结直肠癌 toldts间隙 外科平面 影像解剖学
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三基色测量法在S-GAP推进剂火焰温度分布中的应用(英文) 被引量:2
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作者 蔚红建 付小龙 +3 位作者 李吉祯 樊学忠 王瑛 张国防 《固体火箭技术》 EI CAS CSCD 北大核心 2013年第1期133-137,共5页
介绍了一种测量推进剂火焰温度的新方法,即三基色测量法(PCM)。采用三基色测量法测试了S-GAP推进剂(以HMX为氧化剂)的燃烧火焰温度。结果表明,随着的压强增加,S-GAP火焰区更接近燃烧表面;随着推进剂中HMX的增加,暗区变薄。S-GAP推进剂... 介绍了一种测量推进剂火焰温度的新方法,即三基色测量法(PCM)。采用三基色测量法测试了S-GAP推进剂(以HMX为氧化剂)的燃烧火焰温度。结果表明,随着的压强增加,S-GAP火焰区更接近燃烧表面;随着推进剂中HMX的增加,暗区变薄。S-GAP推进剂的火焰温度分布呈等温线形式,1 MPa下火焰温度范围为970~1 600℃,当压强增大为3MPa时,火焰温度范围为1 200~2 200℃。PCM法与热电偶方法测量的最高燃烧火焰温度值较为接近。 展开更多
关键词 s-gap推进剂 三基色测量法 燃烧 火焰温度
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2021年玛多M_(S) 7.4地震前M_(S) 3、M_(S) 4地震空区嵌套异常分析
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作者 张丽峰 黄浩 +3 位作者 赵玉红 刘文邦 胡维云 郭瑛霞 《地震地磁观测与研究》 2023年第3期18-26,共9页
利用地震活动图像等传统测震学方法,对玛多M_(S)7.4地震前的M_(S)3、M_(S)4地震空区嵌套异常演化过程作进一步梳理分析,并进行了回顾总结,得出如下认识和结论:(1)该地震空区具有孕育强震的能力且出现视应力高值现象,预示着区内有发震危... 利用地震活动图像等传统测震学方法,对玛多M_(S)7.4地震前的M_(S)3、M_(S)4地震空区嵌套异常演化过程作进一步梳理分析,并进行了回顾总结,得出如下认识和结论:(1)该地震空区具有孕育强震的能力且出现视应力高值现象,预示着区内有发震危险性;(2)未来主震震中出现在空区嵌套的交界区附近,这一特征对于认识空区嵌套异常、缩小预测发震区域极其重要;(3)回顾玛多地震前空区演化过程,有2次显著地震事件,使跟踪从中长期转为中短期再转为短期,这可为空区跟踪过程中发震紧迫性的判定不断积累经验。 展开更多
关键词 玛多M_(s) 7.4地震 空区嵌套 异常认识 显著地震
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Local resonance phononic band gaps in modifiedtwo-dimensional lattice materials 被引量:3
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作者 Wei Liu Ji-Wei Chen Xian-Yue Su 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第3期659-669,共11页
In this paper, modified two-dimensional peri- odic lattice materials with local resonance phononic band gaps are designed and investigated. The design concept is to introduce some auxiliary structures into conventiona... In this paper, modified two-dimensional peri- odic lattice materials with local resonance phononic band gaps are designed and investigated. The design concept is to introduce some auxiliary structures into conventional pe- riodic lattice materials. Elastic wave propagation in this kind of modified two-dimensional lattice materials is studied us- ing a combination of Bloch's theorem with finite element method. The calculated frequency band structures of illus- trative modified square lattice materials reveal the existence of frequency band gaps in the low frequency region due to the introduction of the auxiliary structures. The mechanism underlying the occurrence of these frequency band gaps is thoroughly discussed and natural resonances of the auxiliary structures are validated to be the origin. The effect of geo- metric parameters of the auxiliary structures on the width of the local resonance phononic band gaps is explored. Finally, a conceptual broadband vibration-insulating structure based on the modified lattice materials is designed and its capabil- ity is demonstrated. The present work is anticipated to be useful in designing structures which can insulate mechanical vibrations within desired frequency ranges. 展开更多
关键词 Modified lattice materials Bloch's theoremLocal resonance phononic band gaps Vibration insulation
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Bone Transport in Tibial Gap Non-Union—A Series of 25 Cases 被引量:1
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作者 Manish Kiran Rabi Jee 《Open Journal of Orthopedics》 2012年第4期144-149,共6页
Gap non-union of the tibia is frequently associated with deformity, infection and shortening. Ilizarov’s method of bone transport was used in the management of twenty-five cases of gap non-union of the tibia. The mea... Gap non-union of the tibia is frequently associated with deformity, infection and shortening. Ilizarov’s method of bone transport was used in the management of twenty-five cases of gap non-union of the tibia. The mean bone gap was 6.53 cm (range 4 to 12 cm). Union was achieved in all cases within a mean period of 11.12 months. The mean time taken for union, per centimeter of bone gap was found to be 1.7 months/cm. Pin tract infection was the commonest complication, seen in 9 cases (36%). The other complications encountered were neuropraxia (n = 3) deviation of the transported bone segment (n = 7), buckling of skin at the advancing side of bone (n = 4), traumatic corticotomy (n = 3), incomplete corticotomy (n = 1), equinus deformity (n = 4), knee stiffness (n = 4) and curling of toes (n = 4). The bone healing results were excellent in 92% of cases and good in 8% of cases. The functional results were excellent in 84% of cases, good in 12% and fair in 4% of cases. Thus bone transport by Ilizarov’s method manages the bone loss and the associated conditions with good bone healing and functional results. 展开更多
关键词 TIBIAL gap NON-UNION BONE TRANsPORT Ilizarov’s Method
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Effect of Air Gap under Fabric on Thermal Protective Performance Using an Improved Apparatus 被引量:1
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作者 李小辉 卢业虎 +2 位作者 周亮 李俊 王云仪 《Journal of Donghua University(English Edition)》 EI CAS 2011年第6期595-598,共4页
The bench top test is one of the most important and effective methods to evaluate the total thermal protective performance(TPP) of firefighters' protective clothing,which is greatly influenced by the air gaps entr... The bench top test is one of the most important and effective methods to evaluate the total thermal protective performance(TPP) of firefighters' protective clothing,which is greatly influenced by the air gaps entrapped.In this paper,to investigate the effect of air gap width on TPP,a new improved apparatus with two height changeable buttons to hold the thermal sensor was developed to get a series of air gap sizes from 0 mm to 40 mm.The TPP of two types of flame-resistant outer fabrics was measured with TPP test apparatus respectively.Analysis of temperature rise with each air gap width was made to determine the effects of different air gaps on protective performance.It was indicated that air gap size had great effect on TPP of fabrics in the bench top test.An air gap width above 8 mm was suggested for the thermal protective clothing design. 展开更多
关键词 air gap thermal protective performance(TPP) bench top test firefig hter’s protective clothing
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将In_(2)O_(3)/CdSe-DETA纳米复合材料中的电荷转移从Type-Ⅰ转变为S-Scheme以提高光催化制氢的活性和稳定性
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作者 李真 刘雯 +3 位作者 陈春旭 马婷婷 张金锋 王正华 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第6期64-74,共11页
化石能源的问题限制了人类的发展。解决这个问题的有效方法是发展可持续性的清洁能源。近年来,氢气作为一种新型的清洁能源被争相报道。氢气燃烧热很大,且产物只有水,完全符合绿色环保可持续性能源的特点。因此,解决氢能源的生产方法就... 化石能源的问题限制了人类的发展。解决这个问题的有效方法是发展可持续性的清洁能源。近年来,氢气作为一种新型的清洁能源被争相报道。氢气燃烧热很大,且产物只有水,完全符合绿色环保可持续性能源的特点。因此,解决氢能源的生产方法就可以有效地解决能源危机问题。自TiO_(2)在1972年作为光催化剂分解水产生氢气开始,半导体光催化剂分解水产生氢气登上了历史的舞台。然而,单一组分光催化剂的固有缺点限制了它的实际应用,寻找克服单一组分光催化剂缺点的解决方案仍然具有挑战性。相对于单一的光催化剂,复合材料光催化剂可以更有效地分离光生电子和空穴,增加光催化析氢反应的速率。因此,通过选择复合材料异质结处合适的光催化机制(如:S-scheme),可以进一步提升催化剂的光催化析氢活性和稳定性。本文通过改变合成条件获得了一系列具有不同带隙宽度的单一CdSe-DETA光催化剂。光催化实验显示调节CdSe-DETA的带隙(2.31eV)可以获得最佳的光催化产氢活性,但是其稳定性很差。因此,我们将CdSe-DETA纳米花附着在In2O3多孔纳米片表面,构建了In_(2)O_(3)/CdSe-DETA纳米复合材料,以提升光催化析氢活性,稳定性和光电流响应。In_(2)O_(3)/CdSe-DETA纳米复合材料中异质结的类型可随着CdSe-DETA带隙宽度的改变而变化。随着CdSe-DETA带隙宽度的增加,异质结的类型可从Type-I型转变到S-scheme型。相对于单一光催化剂和Type-I型光催化剂,S-scheme型In_(2)O_(3)/CdSe-DETA纳米复合材料具有更高的光催化活性以及良好的稳定性。因此,我们选择S-scheme异质结的In_(2)O_(3)/CdSe-DETA纳米复合材料来获得光催化活性和稳定性的最大收益。此外,我们通过差分电荷密度计算结合实验结果证实了S-scheme异质结的存在。S-scheme异质结In_(2)O_(3)/CdSe-DETA纳米复合材料有效分离了光生电子和空穴,最大程度地利用复合材料的导带和价带,高效且稳定的光催化析氢。本研究展示了一种调制载流子转移机制的策略,可为开发高效的析氢光催化剂提供借鉴。 展开更多
关键词 带隙 s-scheme 理论计算 析氢 光腐蚀
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反应溅射沉积Zn(O,S)薄膜的全成分调控和光学性能修饰
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作者 黄星烨 韩钰 +7 位作者 赵笑昆 陈静允 范子超 孙祺 林舒平 钟大龙 温思同 李博研 《材料导报》 CSCD 北大核心 2023年第S01期32-36,共5页
在传统的CIGS薄膜太阳能电池中,CdS薄膜通常起到缓冲层的作用,但Cd有毒且不环保。无镉缓冲层的研究对于提高CIGS电池的环保性具有重要的现实意义。本工作采用射频反应磁控溅射制备Zn(O,S)薄膜,并研究了薄膜的成分、表面形貌、光学带隙... 在传统的CIGS薄膜太阳能电池中,CdS薄膜通常起到缓冲层的作用,但Cd有毒且不环保。无镉缓冲层的研究对于提高CIGS电池的环保性具有重要的现实意义。本工作采用射频反应磁控溅射制备Zn(O,S)薄膜,并研究了薄膜的成分、表面形貌、光学带隙与溅射气氛中氧含量之间的关系。将Ar/O_(2)流量从0.5 sccm增加到8 sccm时,薄膜中的S含量从82%降低到13%。随着溅射气氛中O含量的增加,Zn(O,S)薄膜的O1s结合能从O-Ⅲ(~532 eV)逐渐向O-Ⅰ(~530 eV)移动,薄膜中的S含量逐渐降低的同时出现了S^(6+)和S^(4+)。表面形貌表征表明Zn(O,S)可以在CIGS吸收层表面形成致密覆盖。光学带隙具有弯曲特性且在3.07~3.52 eV可调,在S/(O+S)比为56%时获得了3.07 eV的最小光学带隙值。以溅射法Zn(O,S)作为缓冲层制备的CIGS太阳能电池的转换效率为10.19%,且对光浴处理不敏感。溅射制备的Zn(O,S)薄膜促进了CIGS太阳能电池的工业化应用。 展开更多
关键词 氧硫化锌 铜铟镓硒 磁控溅射 光学带隙
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Phenotypic changes of Schwann cells on the proximal stump of injured peripheral nerve during repair using small gap conduit tube
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作者 Shi-jun Zhang Wen-liang Wu +2 位作者 Kai-yun Yang Yun-zhen Chen Hai-chun Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第9期1538-1543,共6页
Dedifferentiation of Schwann cells is an important feature of the response to peripheral nerve injury and specific negative myelination reg- ulators are considered to have a major role in this process. However, most e... Dedifferentiation of Schwann cells is an important feature of the response to peripheral nerve injury and specific negative myelination reg- ulators are considered to have a major role in this process. However, most experiments have focused on the distal nerve stump, where the Notch signaling pathway is strongly associated with Schwann cell dedifferentiation and repair of the nerve. We observed the phenotypic changes of Schwann cells and changes of active Notch signaling on the proximal stump during peripheral nerve repair using small gap conduit tubulization. Eighty rats, with right sciatic nerve section of 4 mm, were randomly assigned to conduit bridging group and control group (epineurium suture). Glial fibrillary acidic protein expression, in myelinating Schwann cells on the proximal stump, began to up-reg- ulate at 1 day after injury and was still evident at 5 days. Compared with the control group, Notchl mRNA was expressed at a higher level in the conduit bridging group during the first week on the proximal stump. Hesl mRNA levels in the conduit bridging group significantly increased compared with the control group at 3, 5, 7 and 14 days post-surgery. The change of the Notch intracellular domain shared a simi- lar trend as Hesl mRNA expression. Our results confirmed that phenotypic changes of Schwann cells occurred in the proximal stump. The differences in these changes between the conduit tubulization and epineurium suture groups correlate with changes in Notch signaling. This suggests that active Notch signaling might be a key mechanism during the early stage of neural regeneration in the proximal nerve stump. 展开更多
关键词 nerve regeneration schwann cells nerve injury small gap conduit therapy CHITIN peripheral nerve injury Notch signaling Notch 1 HEs1 glial fibrillary acidic protein s100 neural regeneration
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Science Meets Philosophy:Metaphysical Gap&Bilateral Brain
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作者 Hermann G.W.Burchard 《Journal of Philosophy Study》 2020年第10期599-614,共16页
The essay brings a summation of human efforts seeking to understand our existence.Plato and Kant&cognitive science complete reduction of philosophy to a neural mechanism,evolved along elementary Darwinian principl... The essay brings a summation of human efforts seeking to understand our existence.Plato and Kant&cognitive science complete reduction of philosophy to a neural mechanism,evolved along elementary Darwinian principles.Plato in his famous Cave Allegory explains that between reality and our experience of it there exists a great chasm,a metaphysical gap,fully confirmed through particle-wave duality of quantum physics.Kant found that we have two kinds of perception,two senses:By the spatial outer sense we perceive phenomena,objects in space.Our temporal inner sense lets us perceive our inner state,noumena.Kant’s two senses are fully confirmed through bilateral brain duality of cognitive science.The bilateral brain serves inner,temporal sense,logic&noumena in the left hemisphere.The right brain half is for the outer,spatial sense,geometry&phenomena.Weform awhole system,a bilateral interior cosmos,a kind of world model,expressing what may lie beyond the metaphysical gap.In the right brain we build a phenomenal cosmos,to resemble the outer environment.In the brain’s left hemisphere a noumenal cosmos,amodel of our private world including Saint Teresa of Avila’s castillo interior.The cosmos is regularly updated with novel sense data integrated into our memory banks.This was recognized early by Helmholtz(1860s).Our lives,health&well-being depend on us keeping our interior cosmos in good order.This used to be seen as saving one’s precious soul from perdition.While we endeavour to keep our phenomenal cosmos neat&orderly by protecting the environment from harm,our noumenal cosmos to be livable requires us to engage in ethical conduct.This bilateral cosmos is responsible for our common sense judgment power,that we depend on for being able to lead a good&benign life.The 200 million neurons of BA10 in the prefrontal lobe have global access to the interior cosmos,&apply massive feedback to identify environmental conditions rapidly.The global access also gives conscious presence of the individual to itself,all that is present in the interior cosmos,for total freedom of action.In the left brain private ego,we are guarded by faith in divine mercy,&guided to choose the best course of action,able to survive under themost adverse conditions.For this,wereceive directions from the Holy Ghost in Saint Teresa’s castillo interior. 展开更多
关键词 Kant’s inner&outer senses orderly inner self&chaotic outer environment brain laterality interior cosmos metaphysical gap
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The Gaps between Primes
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作者 Pal Doroszlai Horacio Keller 《Advances in Pure Mathematics》 2022年第12期757-771,共15页
The union of the straight and—of the over a point of reflection—reflected union of the series of the arithmetic progression of primes results the double density of occupation of integer positions by multiples of the... The union of the straight and—of the over a point of reflection—reflected union of the series of the arithmetic progression of primes results the double density of occupation of integer positions by multiples of the primes. The remaining free positions represent diads of equidistant primes to the point of reflection: in case the point of reflection is an even number, they satisfy Goldbach’s conjecture. Further, it allows to prove, that the number of twin primes is unlimited. The number of all greater gaps as two between primes has well defined lower limit functions as well: it is evaluated with the local density of diads, multiplied with the total of the density of no-primes of all positions over the distance between the components of the diads (the size of the gaps). The infinity of these lower limit functions proves the infinity of the number of gaps of any size between primes. The connection of the infinite number of diads to the infinity of the number of gaps of any size is the aim of the paper. 展开更多
关键词 Twin Primes Prime gaps Goldbach’s Conjecture
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The Technological Gap between China and World Frontiers at the Industrial Level:1985-2009
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作者 陆剑 柳剑平 程时雄 《China Economist》 2015年第1期88-101,共14页
Using sequential DEA methodology, this paper has measured the variations in the technological gaps of China's industrial sectors compared with the world frontiers of technology. From a temporal dimension, variations ... Using sequential DEA methodology, this paper has measured the variations in the technological gaps of China's industrial sectors compared with the world frontiers of technology. From a temporal dimension, variations in the technological gaps of China's industrial sectors can be divided into the following four stages: slight abatement of technological gaps between 1985 and 1992, and between 1999 and 2007; stagnation in the variation of technological gaps between 1994 and 1999; and continuous abatement of technological gaps between 2008 and 2009. From the industry dimension, by 2009, 58.8% of China's industrial sectors had gradually reached or approached the world frontiers of technology; 29.4% of industrial sectors had experienced technological improvements but still lagged far behind the world frontiers of technology; 11.8% of industrial sectors significantly lagged behind the world frontiers of technology. 展开更多
关键词 world frontiers of technology China's technology gap at industry level
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Energy Gap in Saturn’s Rings
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作者 Andrey Yu Pospelov Vladimir V. Tchernyi 《Journal of Modern Physics》 2019年第4期477-485,共9页
In this article, we consider, based on the super-diamagnetic model, the new problems of Saturn’s rings discovered by Cassini, such as: 1) anomalous purity of water ice;2) Saturn’s magnetic field alignment with the p... In this article, we consider, based on the super-diamagnetic model, the new problems of Saturn’s rings discovered by Cassini, such as: 1) anomalous purity of water ice;2) Saturn’s magnetic field alignment with the planet’s rotation axis;3) “ring rain” of the submicron particles;4) the deviation in the qualitative composition of the “rain” from the composition of the rings;5) “dirt” concentrated in the ring gaps;6) “plateaus” in Saturn’s C ring;7) age of the rings;8) roll-off in the spectrum of Saturn’s rings, and 9) “propellers” in Saturn’s A ring. Interpretation of Cassini’s observations of spectral roll-off in Saturn’s rings in the wavelength range from 100 micrometers to 0.5 mm is given. It was concluded that the substance of the rings could be in the superconducting state. An explanation of the Cassini spectral data is given using the hypothesis of the existence of a superconducting energy gap in the substance of rings. 展开更多
关键词 sATURN RINGs CAssINI CIRs Interpretation super-Diamagnetic Model superconducting Energy gap Ring RAIN PLATEAUs and PROPELLERs in saturn’s RINGs
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How Big Is the Gap Between China's East and West?
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作者 Xu Hongwei Li Yongwen 《China's Foreign Trade》 2000年第3期41-42,共2页
关键词 than How Big Is the gap Between China’s East and West
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Exploring Brain Age Calculation Models Available for Alzheimer's Disease
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作者 Lihan Wang Honghong Liu +2 位作者 Weijia Liu Qunxi Dong Bin Hu 《Journal of Beijing Institute of Technology》 EI CAS 2023年第2期181-187,共7页
The advantages of structural magnetic resonance imaging(sMRI)-based multidimensional tensor morphological features in brain disease research are the high sensitivity and resolution of sMRI to comprehensively capture t... The advantages of structural magnetic resonance imaging(sMRI)-based multidimensional tensor morphological features in brain disease research are the high sensitivity and resolution of sMRI to comprehensively capture the key structural information and quantify the structural deformation.However,its direct application to regression analysis of high-dimensional small-sample data for brain age prediction may cause“dimensional catastrophe”.Therefore,this paper develops a brain age prediction method for high-dimensional small-sample data based on sMRI multidimensional morphological features and constructs brain age gap estimation(BrainAGE)biomarkers to quantify abnormal aging of key subcortical structures by extracting subcortical structural features for brain age prediction,which can then establish statistical analysis models to help diagnose Alzheimer’s disease and monitor health conditions,intervening at the preclinical stage. 展开更多
关键词 brain age gap estimation(BrainAGE) Alzheimer’s disease(AD) structural magnetic resonance imaging(sMRI)
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蜂巢晶格材料中的扩展s波超导电性
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作者 于贤丰 张李婷 蓝郁 《喀什大学学报》 2023年第6期31-35,共5页
利用动能驱动的超导电性理论研究了掺杂蜂巢晶格材料的非常规超导电性.结果表明,掺杂蜂巢晶格材料扩展s波对称性的电荷载流子配对能隙参数随掺杂浓度的变化呈圆顶状,说明掺杂蜂巢晶格材料中是可能出现扩展s波超导态的;电荷载流子配对能... 利用动能驱动的超导电性理论研究了掺杂蜂巢晶格材料的非常规超导电性.结果表明,掺杂蜂巢晶格材料扩展s波对称性的电荷载流子配对能隙参数随掺杂浓度的变化呈圆顶状,说明掺杂蜂巢晶格材料中是可能出现扩展s波超导态的;电荷载流子配对能隙参数随温度的增加而逐渐减小,在超导转变温度处变为零,而超导转变温度随掺杂浓度的变化也呈圆顶状,与实验结果定性一致;动能驱动的超导电性理论同样适用于定性研究具有蜂巢晶格结构的掺杂莫特绝缘体的超导电性. 展开更多
关键词 扩展s 超导电性 蜂巢晶格材料 动能驱动的超导电性理论 电荷载流子配对能隙参数
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均匀磁场下二维拓扑绝缘体边缘态的多重Andreev反射研究
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作者 杨雪 吕博 《现代电子技术》 北大核心 2024年第4期17-22,共6页
研究均匀磁场下的二维拓扑绝缘体在超导隧道结中的电压偏置约瑟夫森结的输运性质,电流-电压特性显示了马约拉纳束缚态的存在。在亚谐隙结构中,也可以观察到磁场对超导能隙的影响。研究结果表明,在S波超导体/正常金属/S波超导结的隧道谱... 研究均匀磁场下的二维拓扑绝缘体在超导隧道结中的电压偏置约瑟夫森结的输运性质,电流-电压特性显示了马约拉纳束缚态的存在。在亚谐隙结构中,也可以观察到磁场对超导能隙的影响。研究结果表明,在S波超导体/正常金属/S波超导结的隧道谱中存在亚谐隙结构。透明度只影响超导结的零偏压电导值的大小,而不影响亚谐隙结构的位置。但是在磁场作用下,亚谐隙结构会发生变化,不再固定出现在特定位置。这一结果对应于拓扑螺旋态中超导和铁磁序之间的相互作用。 展开更多
关键词 拓扑绝缘体 多重Andreev反射 超导隧道结 约瑟夫森结 亚谐隙结构 马约拉纳束缚态 s波超导体 准粒子波函数
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星型GAP与固体推进剂填料的表界面性能 被引量:5
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作者 蔚红建 付小龙 +4 位作者 邓重清 樊学忠 周文静 李吉祯 张伟 《固体火箭技术》 EI CAS CSCD 北大核心 2011年第2期211-213,219,共4页
采用动态接触角和界面张力仪,研究了星型GAP(S-GAP)与AP、RDX和HMX之间的表界面性能。结果表明,星型GAP与固体填料间的界面张力关系为γSL(S-GAP/RDX)<γSL(S-GAP/HMX)<γSL(S-GAP/AP);星型GAP与固体填料间的粘附功关系为Wa(S-GAP... 采用动态接触角和界面张力仪,研究了星型GAP(S-GAP)与AP、RDX和HMX之间的表界面性能。结果表明,星型GAP与固体填料间的界面张力关系为γSL(S-GAP/RDX)<γSL(S-GAP/HMX)<γSL(S-GAP/AP);星型GAP与固体填料间的粘附功关系为Wa(S-GAP/AP)<Wa(S-GAP/RDX)<Wa(S-GAP/HMX)。星型GAP与固体填料间的粘接界面的作用力主要为界面分子间作用力。S-GAP与RDX、HMX之间主要由于氢键、偶极等作用而形成较强的界面作用;S-GAP与AP间由于分子间作用力较小,故界面作用较弱。 展开更多
关键词 固体推进剂 星型gap 接触角 表面张力 粘附功
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“S”形试件的五轴数控机床综合动态精度检测特性研究 被引量:14
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作者 杜丽 张信 +2 位作者 王伟 付振华 石荣波 《电子科技大学学报》 EI CAS CSCD 北大核心 2014年第4期629-635,共7页
以ISO国际标准试件、NAS979系列试件、NCG试件等为例,比较了目前国内外常用机床精度检测试件的检测性能与特点,计算了"S"形检测试件的开闭角、扭曲角、曲线曲率以及曲面法曲率等特征,研究了"S"形检测试件在几何造... 以ISO国际标准试件、NAS979系列试件、NCG试件等为例,比较了目前国内外常用机床精度检测试件的检测性能与特点,计算了"S"形检测试件的开闭角、扭曲角、曲线曲率以及曲面法曲率等特征,研究了"S"形检测试件在几何造型方面的特性,证明了"S"形试件能基本体现和覆盖机床的各种复杂姿态,以及在机床多轴联动精度检测和机床动态刚度特性检测等方面更具全面性。为基于"S"形检测试件的五轴数控机床动态精度检测提供相应的科学依据,为五轴数控机床精度检测试件的型面构造研究提供理论参考,有助于"S"形试件国际标准草案的制定与推广。 展开更多
关键词 法曲率 开闭角 反向间隙 s”形检测试件 扭曲角
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金思维对Aβ_(42)所致AD模型大鼠海马CA1区GAP-43表达的影响 被引量:4
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作者 田金洲 徐意 +5 位作者 时晶 尹军祥 姬志鹃 赵志炜 盛树力 王永炎 《中西医结合心脑血管病杂志》 2007年第3期217-219,共3页
目的观察金思维对β淀粉样蛋白(Aβ)所致阿尔茨海默病(AD)模型大鼠海马CA1区GAP-43异常表达的影响。方法应用凝聚态Aβ1-42在大鼠海马内注射以建立动物模型。造模3d后采用Morris水迷宫法筛选学习记忆积分异常者,纳入药物实验。给药4周后... 目的观察金思维对β淀粉样蛋白(Aβ)所致阿尔茨海默病(AD)模型大鼠海马CA1区GAP-43异常表达的影响。方法应用凝聚态Aβ1-42在大鼠海马内注射以建立动物模型。造模3d后采用Morris水迷宫法筛选学习记忆积分异常者,纳入药物实验。给药4周后,取脑冷冻切片,采用免疫组化法和计算机图像分析技术测定海马CA1区GAP-43阳性神经元数目,采用Image-Proplus显微图像分析系统测定海马CA1区GAP-43阳性细胞的免疫反应产物的光密度(OD)值。结果给药4周后,金思维组海马CA1区GAP-43阳性细胞数升至77.06个±14.66个,不仅显著高于模型组的52.33个±28.45个(P<0.01),而且与多奈哌齐组(51.26个±22.44个)相比亦有统计学意义(P<0.01)。但金思维组海马CA1区GAP-43阳性细胞OD值(75.44±5.29)与多奈哌齐组(73.09±5.18)相比无统计学意义(P>0.05)。结论金思维可使Aβ所致AD模型大鼠海马CA1区GAP-43的表达量增加,为金思维提取物促神经生长提供了新的证据。 展开更多
关键词 金思维 阿尔茨海默病 轴突生长 gap-43
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