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Interconnected microstructure and flexural behavior of Ti_(2)C-Ti composites with superior Young’s modulus
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作者 Fengbo Sun Rui Zhang +3 位作者 Fanchao Meng Shuai Wang Lujun Huang Lin Geng 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第9期2088-2101,共14页
To enhance the Young’s modulus(E)and strength of titanium alloys,we designed titanium matrix composites with intercon-nected microstructure based on the Hashin-Shtrikman theory.According to the results,the in-situ re... To enhance the Young’s modulus(E)and strength of titanium alloys,we designed titanium matrix composites with intercon-nected microstructure based on the Hashin-Shtrikman theory.According to the results,the in-situ reaction yielded an interconnected microstructure composed of Ti_(2)C particles when the Ti_(2)C content reached 50vol%.With widths of 10 and 230 nm,the intraparticle Ti lamellae in the prepared composite exhibited a bimodal size distribution due to precipitation and the unreacted Ti phase within the grown Ti_(2)C particles.The composites with interconnected microstructure attained superior properties,including E of 174.3 GPa and ultimate flexural strength of 1014 GPa.Compared with that of pure Ti,the E of the composite was increased by 55% due to the high Ti_(2)C content and interconnected microstructure.The outstanding strength resulted from the strong interfacial bonding,load-bearing capacity of interconnected Ti_(2)C particles,and bimodal intraparticle Ti lamellae,which minimized the average crack driving force.Interrupted flexural tests revealed preferential crack initiation along the{001}cleavage plane and grain boundary of Ti_(2)C in the region with the highest tensile stress.In addition,the propagation can be efficiently inhibited by interparticle Ti grains,which prevented the brittle fracture of the composites. 展开更多
关键词 titanium matrix composites titanium carbide INTERFACE Young’s modulus flexural behavior
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Rapid, accurate and serotype independent pipeline for in silico epitope mapping of SARS-CoV-2 antigens: a combined machine learning and Chou’s pseudo amino acid composition method
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作者 Arash Rahmani Mokhtar Nosrati 《Medical Data Mining》 2023年第3期1-9,共9页
Here,a new integrated machine learning and Chou’s pseudo amino acid composition method has been proposed for in silico epitope mapping of severe acute respiratorysyndrome-like coronavirus antigens.For this,a training... Here,a new integrated machine learning and Chou’s pseudo amino acid composition method has been proposed for in silico epitope mapping of severe acute respiratorysyndrome-like coronavirus antigens.For this,a training dataset including 266 linear B-cell epitopes,1,267 T-cell epitopes and 1,280 non-epitopes were prepared.The epitope sequences were then converted to numerical vectors using Chou’s pseudo amino acid composition method.The vectors were then introduced to the support vector machine,random forest,artificial neural network,and K-nearest neighbor algorithms for the classification process.The algorithm with the highest performance was selected for the epitope mapping procedure.Based on the obtained results,the random forest algorithm was the most accurate classifier with an accuracy of 0.934 followed by K-nearest neighbor,artificial neural network,and support vector machine respectively.Furthermore,the efficacies of predicted epitopes by the trained random forest algorithm were assessed through their antigenicity potential as well as affinity to human B cell receptor and MHC-I/II alleles using the VaxiJen score and molecular docking,respectively.It was also clear that the predicted epitopes especially the B-cell epitopes had high antigenicity potentials and good affinities to the protein targets.According to the results,the suggested method can be considered for developing specific epitope predictor software as well as an accelerator pipeline for designing serotype independent vaccine against the virus. 展开更多
关键词 severe acute respiratory syndrome-like coronavirus machine learning Chou’s pseudo amino acid composition epitope based vaccine
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基于哨兵函数和S变换的风力机叶片材料损伤特性研究
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作者 廖力达 舒王咏 +3 位作者 张芝铭 刘亮 冯飞 陈为强 《太阳能学报》 EI CAS CSCD 北大核心 2024年第7期656-663,共8页
利用声发射检测技术研究玻璃纤维增强环氧树脂复合材料的损伤特性,在此过程中,采用哨兵函数来表征该材料的损伤程度,并通过S变换和模糊C均值(FCM)聚类来分析声发射信号,从而获得材料的损伤特征。三点弯曲实验结束后对试件断口进行扫描... 利用声发射检测技术研究玻璃纤维增强环氧树脂复合材料的损伤特性,在此过程中,采用哨兵函数来表征该材料的损伤程度,并通过S变换和模糊C均值(FCM)聚类来分析声发射信号,从而获得材料的损伤特征。三点弯曲实验结束后对试件断口进行扫描电子显微镜(SEM)拍照来验证,可得:通过对SEM照片的分析得到基体开裂、纤维脱粘、分层破坏、纤维断裂4种损伤模式;对整个声发射事件进行哨兵函数分析,观察到试件在弯曲过程中哨兵函数曲线呈明显下降趋势;对依据哨兵函数划分的不同阶段的信号进行VMD降噪处理,然后采用S变换进行时频分析得到不同损伤的特征频率,最后采用FCM聚类进行验证。结果表明:哨兵函数值的突变可作为材料断裂的预警信号,材料损伤类型的识别可依据S变换的频率分布结果进行确定。 展开更多
关键词 风力机叶片 复合材料 声发射 损伤特性 哨兵函数 s变换
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一种基于随机求反的S盒抗DPA攻击安全结构
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作者 胡晓婷 戴泽龙 +1 位作者 覃中平 巩固 《计算机技术与发展》 2024年第11期109-116,共8页
DPA攻击(差分功耗攻击)作为一种重要的侧信道攻击方法,因其成功率较高而成为加密算法面临的主要威胁之一。S盒是分组加密算法(高级加密标准(AES)、国产商业密码(SM4)等)中唯一的非线性运算,很大程度上决定了相关加密算法的安全性。S盒... DPA攻击(差分功耗攻击)作为一种重要的侧信道攻击方法,因其成功率较高而成为加密算法面临的主要威胁之一。S盒是分组加密算法(高级加密标准(AES)、国产商业密码(SM4)等)中唯一的非线性运算,很大程度上决定了相关加密算法的安全性。S盒的实现主要分为:查表法、组合逻辑和复合域方法。复合域方法因将S盒中的GF(28)域上的求逆运算分解到低阶域上而使其硬件实现具有高性能、低面积等优势。该文提出了一种基于随机求反的复合域S盒抗DPA攻击安全结构,并据此设计了两类抗DPA攻击的AES安全结构:一种是基于随机取反的AES安全结构(RC-AES安全结构),另一种是基于随机取反与一阶掩码结合的AES安全结构(RC-M-AES安全结构)。实验证明,相较于已知文献中基于掩码保护的AES,该文提出的RC-AES结构只需增加微小的面积开销就能有效抵抗DPA攻击,展现出显著的面积优势。同时,RC-M-AES安全结构能在微小面积开销下,构建出比单独掩码方案更安全的密码芯片结构。此外,提出的S盒安全结构不仅适用于AES,也适用于任何以替换函数作为唯一非线性运算的加密算法,具有较好的通用性。 展开更多
关键词 复合域 s 随机求反 抗DPA攻击 安全结构 高级加密标准
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Influence of Thermal Treatments on In-depth Compositional Uniformity of Culn(S,Se)2 Thin Films
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作者 谢海兵 刘伟丰 +3 位作者 江国顺 李欣益 严飞 朱长飞 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第4期481-486,I0004,共7页
CuIn(S,Se)2 thin films were prepared by thermal crystallization of co-sputtered Cu-In alloy precursors in S/Se atmosphere. In-depth compositional uniformity is an important prereq- uisite for obtaining device-qualit... CuIn(S,Se)2 thin films were prepared by thermal crystallization of co-sputtered Cu-In alloy precursors in S/Se atmosphere. In-depth compositional uniformity is an important prereq- uisite for obtaining device-quality CuIn(S,Se)2 absorber thin films. In order to figure out the influence of heat treatments on in-depth composition uniformity of CuIn(S,Se)2 thin films, two kinds of reaction temperature profiles were investigated. One process is "one step profile", referring to formation of CuIn(S,Se)2 thin films just at elevated temperature (e.g. 500 ℃). The other is "two step profile", which allows for slow diffusion of S and Se elements into the alloy precursors at a low temperature before the formation and re-crystallization of CuIn(S,Se)2 thin films at higher temperature (e.g. first 250 ℃ then 500 ℃). X-ray diffrac- tion studies reveal that there is a discrepancy in the shape of (112) peak. Samples annealed with "one step profile" have splits on (112) peaks, while samples annealed with "two step profile" have relatively symmetrical (112) peaks. Grazing incident X-ray diffraction and en- ergy dispersive spectrum measurements of samples successively etched in bromine methanol show that CuIn(S,Se)2 thin films have better in-depth composition uniformity after "two step profile" annealing. The reaction mechanism during the two thermal processing was also investigated by X-ray diffraction and Raman spectra. 展开更多
关键词 Thermal treatment In-depth compositional uniformity CuIn(s se)2 thin film
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Soil fungistasis and its relations to soil microbial composition and diversity:A case study of a series of soils with different fungistasis 被引量:8
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作者 Wu Minna Zhang Huiwen +3 位作者 Ll Xinyu Zhang Yan Su Zhencheng Zhang Chenggang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第7期871-877,共7页
Fungistasis is one of the important approaches to control soil-borne plant pathogens.Some hypotheses about the mechanisms for soil fungistasis had been established,which mainly focused on the soil bacterial community ... Fungistasis is one of the important approaches to control soil-borne plant pathogens.Some hypotheses about the mechanisms for soil fungistasis had been established,which mainly focused on the soil bacterial community composition,structure,diversity as well as function.In this study,the bacterial community composition and diversity of a series of soils treated by autoclaving,which coming from the same original soil sample and showing gradient fungistasis to the target soil-borne pathogen fungi Fusarium grami... 展开更多
关键词 soil fungistasis 16s rDNA clone library microbial diversity bacterial community composition
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Weighted composition operators from F(p,q,s) spaces to Bers-type spaces in the unit ball 被引量:2
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作者 LU Xiao-fen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第4期462-472,共11页
This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to ... This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to Bers-type spaces Hv^∞( or little Bers-type spaces Hv,o∞ ), where v is normal. 展开更多
关键词 F(p Q s space Bers-type space weighted composition operator unit ball
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Composite diffuse large B-cell lymphoma and classical Hodgkin's lymphoma of the stomach:Case report and literature review 被引量:5
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作者 Hong-Wei Wang Wen Yang +2 位作者 Lin Wang Yun-Long Lu Jiang-Yang Lu 《World Journal of Gastroenterology》 SCIE CAS 2013年第37期6304-6309,共6页
The combination of classical Hodgkin’s lymphoma(cHL)and non-Hodgkin lymphoma coexisting in the same patient is not common,especially in one extranodal location.Here we present a rare case of composite diffuse large B... The combination of classical Hodgkin’s lymphoma(cHL)and non-Hodgkin lymphoma coexisting in the same patient is not common,especially in one extranodal location.Here we present a rare case of composite diffuse large B-cell lymphoma(DLBCL)and cHL occurring simultaneously in the stomach of a 53-year-old female who presented with upper abdominal discomfort and gas pain.Surgery was performed and the disease was diagnosed pathologically as composite lymphoma of DLBCL and cHL using hematoxylin-eosin and immunohistochemical staining.Epstein-Barr virus(EBV)infection was not detected by in situ hybridization for EBV-encoded RNA or immunohistochemistry for EBV latent membrane protein-1.Polymerase chain reaction analysis from the two distinct components of the tumor demonstrated clonal immunoglobulinκlight chain gene rearrangements.The patient died approximately 11 mo after diagnosis in spite of receiving eight courses of the CHOP and two courses of the rituximab-CHOP(RCHOP) chemotherapy regimen.This case report showed that the two distinct components,DLBCL and cHL,appeared to originate from the same clonal progenitor cell,and that EBV infection was not essential for transformation during the course of tumorigenesis. 展开更多
关键词 compositE LYMPHOMA DIFFUsE large B-CELL LYMPHOMA Hodgkin’s LYMPHOMA sTOMACH
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g-C_(3)N_(4)基S型异质结的构建及其光催化性能研究
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作者 申建宇 刘成宝 +5 位作者 郑磊之 陈丰 钱君超 邱永斌 孟宪荣 陈志刚 《功能材料》 CAS CSCD 北大核心 2024年第1期1077-1085,1097,共10页
为了解决日益严重的环境污染和能源短缺等问题,基于半导体的光催化技术利用太阳能为环境修复和能源储存提供了一种“绿色”可持续的方案。首先介绍了g-C_(3)N_(4)的优点和局限性,以及S型半导体的优势与不足,接着介绍了g-C_(3)N_(4)基S... 为了解决日益严重的环境污染和能源短缺等问题,基于半导体的光催化技术利用太阳能为环境修复和能源储存提供了一种“绿色”可持续的方案。首先介绍了g-C_(3)N_(4)的优点和局限性,以及S型半导体的优势与不足,接着介绍了g-C_(3)N_(4)基S型异质结的电子结构和光催化性质,综述了基于不同类型g-C_(3)N_(4)的S型异质结光催化材料构建和光催化性能的提升策略,并梳理了其部分应用。最后,综述了基于g-C_(3)N_(4)的S型异质结面临的挑战和未来发展趋势,有望为g-C_(3)N_(4)基S型异质结光催化材料的开发和实际应用提供重要的参考。 展开更多
关键词 g-C_(3)N_(4) s型异质结 光催化 复合材料
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Analysis of cultivable aerobic bacterial community composition and screening for facultative sulfate-reducing bacteria in marine corrosive steel 被引量:4
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作者 LI Xiaohong XIAO Hui +7 位作者 ZHANG Wenjun LI Yongqian TANG Xuexi DUAN Jizhou YANG Zhibo WANG Jing GUAN Fang DING Guoqing 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第2期600-614,共15页
Anaerobic, aerobic, and facultative bacteria are all present in corrosive environments. However, as previous studies to address corrosion in the marine environment have largely focused on anaerobic bacteria, limited a... Anaerobic, aerobic, and facultative bacteria are all present in corrosive environments. However, as previous studies to address corrosion in the marine environment have largely focused on anaerobic bacteria, limited attention has been paid to the composition and function of aerobic and facultative bacteria in this process. For analysis in this study, ten samples were collected from rust layers on steel plates that had been immersed in seawater for diff erent periods (i.e., six months and eight years) at Sanya and Xiamen, China. The cultivable aerobic bacterial community structure as well as the number of sulfate-reducing bacteria (SRB) were analyzed in both cases, while the proportion of facultative SRB among the isolated aerobic bacteria in each sample was also evaluated using a novel approach. Bacterial abundance results show that the proportions are related to sea location and immersion time;abundances of culturable aerobic bacteria (CAB) and SRB from Sanya were greater in most corrosion samples than those from Xiamen, and abundances of both bacterial groups were greater in samples immersed for six months than for eight years. A total of 213 isolates were obtained from all samples in terms of CAB community composition, and a phylogenetic analysis revealed that the taxa comprised four phyla and 31 genera. Bacterial species composition is related to marine location;the results show that Firmicutes and Proteobacteria were the dominant phyla, accounting for 98.13% of the total, while Bacillus and Vibrio were the dominant genera, accounting for 53.06% of the total. An additional sixfacultative SRB strains were also screened from the isolates obtained and were found to encompass the genus Vibrio (four strains), Staphylococcus (one strain), and Photobacterium (one strain). It is noteworthy that mentions of Photobacterium species have so far been absent from the literature, both in terms of its membership of the SRB group and its relationship to corrosion. 展开更多
关键词 MARINE corrosive sTEEL cultivable AEROBIC BACTERIA FACULTATIVE sulfate-reducing BACTERIA bacterial community composition 16s RRNA gene sequencing
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Gallbladder bile composition in patients with Crohn's disease 被引量:3
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作者 Annika Lapidus Jan-Erikkerlund Curt Einarsson 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第1期70-74,共5页
AIM: To further elucidate the pathogenesis and mechanisms of the high risk of gallstone formation in Crohn's disease. METHODS: Gallbladder bile was obtained from patients with Crohn's disease who were admitted for... AIM: To further elucidate the pathogenesis and mechanisms of the high risk of gallstone formation in Crohn's disease. METHODS: Gallbladder bile was obtained from patients with Crohn's disease who were admitted for elective surgery (27 with ileal/ileocolonic disease and 7 with Crohn's colitis). Fourteen gallstone patients served as controls. Duodenal bile was obtained from ten healthy subjects before and after the treatment with ursodeoxycholic acid. Bile was analyzed for biliary lipids, bile acids, bilirubin, crystals, and crystal detection time (CDT). Cholesterol saturation index was calculated. RESULTS: The biliary concentration of bilirubin was about 50% higher in patients with Crohn's disease than in patients with cholesterol gallstones. Ten of the patients with Crohn's disease involving ileum and three of those with Crohn's colitis had cholesterol saturated bile. Four patients with ileal disease and one of those with colonic disease displayed cholesterol crystals in their bile. About 1/3 of the patients with Crohn's disease had a short CDT. Treatment of healthy subjects with ursodeoxycholic acid did not increase the concentration of bilirubin in duodenal bile. Several patients with Crohn's disease, with or without ileal resection/disease had gallbladder bile supersaturated with cholesterol and short CDT and contained cholesterol crystals. The biliary concentration of bilirubin was also increased in patients with Crohn's colitis probably not due to bile acid malabsorption. CONCLUSION: Several factors may be of importance for the high risk of developing gallstones of both cholesterol and pigment types in patients with Crohn's disease.The skillful technical assistance of Ms Lisbet Benthin and Ms Ingela Arvidsson is acknowledged. 展开更多
关键词 Bile acid Biliary lipid composition BILIRUBIN Crohn's disease Gallstone disease
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Camellia密码算法S盒的量子电路优化
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作者 吕轶 罗庆斌 +1 位作者 李强 郑圆梦 《计算机科学》 CSCD 北大核心 2024年第S01期1017-1022,共6页
S盒是Camellia密码算法重要的非线性组件。使用Toffoli门、CNOT门和NOT门构建Camellia密码算法S盒的量子电路。为了降低计算的复杂度,根据S盒的代数表达式,将有限域GF(2^(8))中的乘法求逆运算同构到GF((2^(4))^(2))的复合域中的运算,构... S盒是Camellia密码算法重要的非线性组件。使用Toffoli门、CNOT门和NOT门构建Camellia密码算法S盒的量子电路。为了降低计算的复杂度,根据S盒的代数表达式,将有限域GF(2^(8))中的乘法求逆运算同构到GF((2^(4))^(2))的复合域中的运算,构造出Camellia密码算法S盒的量子电路。在优化方面,将仿射矩阵、同构矩阵以及一组CNOT门对应的矩阵先进行乘法操作,再进行综合,使用DORCIS工具优化GF(2^(4))中乘法求逆的量子电路,运用W-Type算法优化矩阵运算的量子电路。最终得到的S盒的量子电路只需使用20个量子比特,52个Toffoli门、178个CNOT门和13个NOT门,Toffoli深度为40,电路深度为130。该量子电路的正确性通过IBM公司的Aer模拟器进行验证。相比于已有的结果,文中使用的量子资源有了进一步的减少。 展开更多
关键词 量子电路 CAMELLIA s 复合域
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SM4密码算法S盒的量子电路优化 被引量:1
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作者 李强 罗庆斌 +2 位作者 吕轶 郑圆梦 沈济南 《密码学报(中英文)》 CSCD 北大核心 2024年第2期455-465,共11页
S盒是SM4密码算法中的重要非线性组件.首先基于复合域理论,将S盒代数表达式中有限域GF(2^(8))中的运算同构到复合域GF((2^(4))2)中的运算,然后使用NCT门库逐步构建并优化各个运算的量子电路,最后综合出完整的S盒量子电路.为降低Toffoli... S盒是SM4密码算法中的重要非线性组件.首先基于复合域理论,将S盒代数表达式中有限域GF(2^(8))中的运算同构到复合域GF((2^(4))2)中的运算,然后使用NCT门库逐步构建并优化各个运算的量子电路,最后综合出完整的S盒量子电路.为降低Toffoli门的使用量,根据GF(24)中乘法计算的代数表达式,选取使用Toffoli门最少的量子电路.为了降低CNOT门的使用量,主要从三方面优化:一是使用最优的CNOT电路综合出4阶矩阵的量子电路;二是采用置换矩阵法以及优化子电路的方式综合出8阶矩阵的量子电路;三是通过先合并计算再综合的思路优化整个S盒中CNOT门的数量.该S盒量子电路使用Qiskit Aer量子模拟器实现,并验证了其正确性.经量子资源分析,该优化的S盒量子电路一共使用了21个量子比特、10个NOT门、152个CNOT门和34个Toffoli门,电路深度为97.Toffoli门数量、总量子逻辑门数量、电路深度等相比已有结果都有较大减少. 展开更多
关键词 量子电路 sM4 s 复合域 优化
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Effect of Lycopus lucidus Turcz.supplementation on gut microflora and short chain fatty acid composition in Crj:CD-1 mice 被引量:1
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作者 EUN NA SUN YOUNG LIM 《BIOCELL》 SCIE 2022年第9期2101-2109,共9页
We investigated the diversity and composition of microflora in feces of Lycopus lucidus Turcz.-fed mice.In addition,we evaluated the production of major cytokines(Interleukin-6 and-10)which are related to inflammation... We investigated the diversity and composition of microflora in feces of Lycopus lucidus Turcz.-fed mice.In addition,we evaluated the production of major cytokines(Interleukin-6 and-10)which are related to inflammation and fatty acid composition of several tissues.16S ribosomal DNA sequencing-based microbiome taxonomic profiling analysis was performed utilizing the EzBioCloud data base.Male mice fed on L.lucidus showed a significantly reduced number of lactic acid bacteria and coliform in the feces compared with the control group(p<0.05).16S rDNA sequencing analysis of fecal samples showed that L.lucidus supplementation decreased the community of harmful microflora(Enterobacteriaceae including Escherichia coli and Bacteroides sp.)in feces compared with the control group(p<0.05).There were no significant differences in mRNA expression of cytokine IL-6 and IL-10 between the control and L.lucidus fed groups.The fecal fatty acid composition in the L.lucidus group had percentages of 4:0,6:0,8:0 and 10:0 in the intestine but those short chain fatty acids were not detected in the control group.Our results showed that L.lucidus supplementation influenced gut environment by decreasing harmful microflora and increased the percentages of several short fatty acids. 展开更多
关键词 Lycopus lucidus Turcz Fatty acid composition Intestinal microflora 16s rDNA sequencing CYTOKINEs
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复合材料层压板S-N曲线模型的综述与评估
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作者 冯炜森 杨成鹏 贾斐 《材料导报》 EI CAS CSCD 北大核心 2024年第22期278-287,共10页
S-N模型是分析预测材料及其结构疲劳寿命的重要基础。本文对复合材料层压板的S-N曲线模型进行了全面综述,并将其归纳为基于数据拟合思想的经验模型和考虑损伤机理的半经验模型。研究发现,应力比是S-N模型需要考虑的关键载荷参数,而包含... S-N模型是分析预测材料及其结构疲劳寿命的重要基础。本文对复合材料层压板的S-N曲线模型进行了全面综述,并将其归纳为基于数据拟合思想的经验模型和考虑损伤机理的半经验模型。研究发现,应力比是S-N模型需要考虑的关键载荷参数,而包含应力比的半经验模型较少、经验模型更为匮乏。拟定了模型评估五个基本标准,选取了两种材料体系、不同铺层结构层合板在不同应力比条件下的八组疲劳数据,对典型S-N模型的表征能力进行了分析评估。结果表明:Weibull模型、Wu模型和Epaarachchi模型在不同疲劳影响因素下均能表现出较强的拟合能力,整体拟合精度较高,而且Weibull模型和Wu模型具有拟合S-N曲线全区间的能力;Basquin模型虽然在理论和工程中经常使用,但预测精度通常并不理想;相较于不包含应力比的模型,包含应力比的模型其表征精度通常比较差,适用范围反而受限;同时,与半经验模型相比,经验模型通常满足边界条件,对不同形式S-N曲线的拟合优度更高,适应能力更强,且适用范围更广。 展开更多
关键词 复合材料层压板 疲劳 寿命预测 s-N模型 模型评估
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WEIGHTED COMPOSITION OPERATORS ON WEIGHTED DIRICHLET SPACES 被引量:3
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作者 刘小松 娄增建 《Acta Mathematica Scientia》 SCIE CSCD 2013年第4期1119-1126,共8页
We characterize the boundedness and compactness of weighted composition operators on weighted Dirichlet spaces in terms of Nevanlinna counting functions and Caxleson measure.
关键词 weighted composition operator weighted Dirichlet space s-Carleson mea-sure Nevanlinna counting function
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PREPARATION,CHARACTERIZATION AND HYDROGENATION PROPERTY OF POLYMER-SUPPORTED Pd-Fe_2O_3 COMPOSITE CATALYSTS
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作者 ZHANG Shengmin HU Weibing ZHANG Manzheng Wuhan University of Technology Hubei Research Institute of Chemistry 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1999年第4期48-52,共5页
A series of polymer- supported Pd -Fe2O3 composite catalysts were prepared and their hydrogenation property mas investigated. It was found that the above catalysts have good catalytic hydrogenation activity for carbon... A series of polymer- supported Pd -Fe2O3 composite catalysts were prepared and their hydrogenation property mas investigated. It was found that the above catalysts have good catalytic hydrogenation activity for carbon - carbon double bonds systems and reusability. Furthermore, XPS and IR spectra shouted that active component in the composite catalysts is atomic Pd(0). An addition of a small amount of Fe2O3 has a promotive action upon hydrogenation activity of the catalysts, which indicated that there are some strong interactions (electron transfer) between Pd(0) and Fe(Ⅲ) species. Based on these results, a possible catalytic hydrogenation mechanism was also suggested. 展开更多
关键词 functional material polymet-sup- ported catalyst composite Pd - F2O3/polystyrene HYDROGENATION mechanism
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电沉积法制备Cu(OH)_(2)/Ni-Co-S复合电极及储能特性研究
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作者 张志文 王润生 +1 位作者 刘泽仪 吕卅 《化工技术与开发》 CAS 2024年第6期1-5,共5页
本文采用两步电沉积技术,以泡沫铜为基底,原位制备了Cu(OH)_(2)/镍钴双金属硫化物(Ni-Co-S)复合电极材料。先采用恒电流沉积技术将泡沫铜表面氧化,得到Cu(OH)_(2),泡沫铜同时作为电极基底和铜的唯一来源,再通过恒电位沉积,将Ni-Co-S均... 本文采用两步电沉积技术,以泡沫铜为基底,原位制备了Cu(OH)_(2)/镍钴双金属硫化物(Ni-Co-S)复合电极材料。先采用恒电流沉积技术将泡沫铜表面氧化,得到Cu(OH)_(2),泡沫铜同时作为电极基底和铜的唯一来源,再通过恒电位沉积,将Ni-Co-S均匀覆盖在Cu(OH)_(2)表面。Cu(OH)_(2)一方面作为活性电极组分参与氧化还原反应,同时作为底层材料,为顶层Ni-Co-S的沉积提供较大的沉积空间,进而形成了更丰富的电化学活性位。基于这种原位电沉积技术以及Cu(OH)_(2)与Ni-Co-S组分的协同作用,Cu(OH)_(2)/Ni-Co-S复合电极表现出增强的赝电容特性,在2mA·cm^(-2)的放电电流密度下,比容量为4.88 F·cm^(-2),库伦效率为88.12%,5000次充放电循环后,比容量保持在初始值的86.38%。 展开更多
关键词 复合电极 电沉积 Cu(OH)_(2) Ni-Co-s
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Closed Range Composition Operators on a General Family of Function Spaces
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作者 M.A.Bakhit 《Analysis in Theory and Applications》 CSCD 2016年第3期215-231,共17页
In this paper, necessary and sufficient conditions for a closed range composition operator CФ on the general family of holomorphic function spaces F(p,q,s) and more generally on α-Besov type spaces F(p,αp-2,s) ... In this paper, necessary and sufficient conditions for a closed range composition operator CФ on the general family of holomorphic function spaces F(p,q,s) and more generally on α-Besov type spaces F(p,αp-2,s) are given. We give a Carleson measure characterization on F (p, αp - 2, s) spaces, then we indicate how Carleson measures can be used to characterize boundedness and compactness of CФ on F(p,q,s) and F(p,αp- 2,s) spaces. 展开更多
关键词 composition operators F(p q s spaces closed range Carleson measure Bloch space Bergman type space
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A Technique of Bilateral Inguinal Hernia Repair Using 10 mm Single Port Access and Bioresorbable Composite Mesh Fixed with Endoclose Sutures: Three Cases Reported
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作者 Wuttichai Thanapongsathorn 《Surgical Science》 2011年第7期388-392,共5页
Purpose: To report a novel technique of laparoscopic 10 mm Single Port Access IntraPeritoneal Onlay Mesh (SPA-IPOM) using bioresorbable composite mesh fixed with Endoclose suture (percutaneous subcutaneous suture) in ... Purpose: To report a novel technique of laparoscopic 10 mm Single Port Access IntraPeritoneal Onlay Mesh (SPA-IPOM) using bioresorbable composite mesh fixed with Endoclose suture (percutaneous subcutaneous suture) in 3 cases of bilateral inguinal hernia. Methods: Laparoscopic SPA-IPOM is done through a 10 mm trocar with one 10 mm instrument that has 5 mm optical lens and 5 mm channel for grasper. After inserting 10 mm trocar at umbilicus using semi-open technique, intraperitoneal anatomical landmark of inguinal her-nia is identified. A 10 × 15 cm pre-tied bioresorbable composite mesh is then placed to cover hernia defect and all three potential area of indirect, direct and femoral hernia. Using Endoclose? needle, each pair of pre-tied sutures is retrieved percutaneously through a needle wound and extracorporeal tied with knot in subcutaneous space. After the upper half of mesh is sutured to the posterior surface of abdominal wall, the lower half of mesh is fixed by hernia tacker to Symphysis Pubis, Cooper Ligament and Iliopubic tract. Re-sults: Three men, average 48 year olds were operated by laparoscopic 10 mm SPA-IPOM for bilateral in-guinal hernia repair using bioresorbable composite mesh. Average operative time was 36 minutes. No imme-diate complication. All patients were discharge on the 2nd post-operative day and average 6 months follow up has no recurrence. Conclusions: Laparoscopic SPA-IPOM is an optional operation and is much easier to be performed. Benefits include operative time saving, cosmesis, early discharge and early return to work. Bio-resorbable composite mesh prevents bowel adhesion, however, is much more expensive. Long term follow up study for complications and recurrence is needed. 展开更多
关键词 10 MM single port Access IntraPeritoneal Onlay MEsH Percutaneous subcutaneous suture BIOREsORBABLE composite MEsH BILATERAL INGUINAL Hernia Repair
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