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Rational construction of densely packed Si/MXene composite microspheres enables favorable sodium storage

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Rare Metals 2022年第5期41卷 1626-1636页

作者： hui-Qi Wang Ya-Xin Zhao Li Gou Li-Yong Wang mei Wang Ying Li Sheng-Liang hu School of Energy and Power Engineering North University of ChinaTaiyuan 030051China School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

The fast and reversible sodiation/desodiation of anode materials remains an indelible yet fascinating ***, a class of the densely packed Si/MXene composite microspheres is constructed and prepared, taking advantages of the synergistic effects of the activated Si nanoparticles and conductive flower-like MXene microspheres with ample ion-diffusion pathways. Consequently,the intrinsic MXene nanosheets with intelligently regulated interlayer spacing can accommodate the volume change induced strain during cycling, and the strong interaction between the Si and MXene matrix greatly contributes to the robust structural stability. As expected, the Si/MXene composite architecture exhibits boosted sodium storage performance, in terms of an inspiring reversible capacity of 751 mAh·g^(-1)at 0.1 A·g^(-1), remarkable long-term cycling stability of 376 mAh·g^(-1)at 0.1 A·g^(-1) over 500 cycles, and outstanding rate capability(after one consecutive current density changing from 0.1 to 2.0 A·g^(-1), a large capacity of 275 mAh·g^(-1) is regained after suddenly returning the initial current density back to 0.1 A·g^(-1) and in the subsequent 200 cycles this composite architecture anode still delivers a capacity of 332 mAh·g^(-1)). The kinetics analysis indicates superior pseudocapacitive property, high electronic conductivity, and favorable sodium-ion adsorption and diffusion capability,confirming fast sodium storage performance. Impressively, ex-situ X-ray diffraction and selected area electron diffraction characterizations corroborate the formation of NaSi;as the main sodiation products during the reversible evolutions of cycled proceeding with sodium-ion insertion. This work sheds light on the elaborate design of silicon-based nanostructured anodes towards advanced high-performance sodium-ion batteries.

关键词： Silicon MXene Composite microspheres Sodium-ion batteries Flower-like anode Efficient sodiumion storage

A 3 to 5 GHz low-phase-noise fractional-N frequency synthesizer with adaptive frequency calibration for GSM/PCS/DCS/WCDMA transceivers

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Journal of Semiconductors 2012年第1期33卷 80-85页

作者： Pan Yaohua mei Niansong Chen hu huang Yumei Hong zhiliang State Key Laboratory of ASIC&Systems Fudan University Shanghai 201203China

A low-phase-noise E-A fractional-N frequency synthesizer for GSM/PCS/DCS/WCDMA transceivers is presented. The voltage controlled oscillator is designed with a modified digital controlled capacitor array to extend the tuning range and minimize phase noise. A high-resolution adaptive frequency calibration technique is introduced to automatically choose frequency bands and increase phase-noise immunity. A prototype is implemented in 0.13 #m CMOS technology. The experimental results show that the designed 1.2 V wideband frequency synthesizer is locked from 3.05 to 5.17 GHz within 30 μs, which covers all five required frequency bands. The measured in-band phase noise are -89, -95.5 and -101 dBc/Hz for 3.8 GHz, 2 GHz and 948 MHz carriers, respectively, and accordingly the out-of-band phase noise are -121, -123 and -132 dBc/Hz at 1 MHz offset, which meet the phase-noise-mask requirements of the above-mentioned standards.

关键词： phase-locked loop loop stability analysis voltage controlled oscillation phase noise

Modulation of spin dynamics in Ni/Pb(Mg_(1/3)Nb_(2/3))O_(3)-PbTiO_(3) multiferroic heterostructure

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Journal of Advanced Ceramics 2022年第3期11卷 515-521页

作者： Hang XU Bo WANG Ji Qi mei LIU Fei TENG Linglong hu Yuan ZHANG Chaoqun QU Ming FENG Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education Jilin Normal UniversityChangchun 130103China Condensed Matter Science and Technology Institute School of Instrumentation Science and EngineeringHarbin Institute of Technology.Harbin 150080China College of Mathematics Jilin Normal UniversitySiping 136000China

Motivated by the fast-developing spin dynamics in ferromagnetic/piezoelectric structures, this study attempts to manipulate magnons (spin-wave excitations) by the converse magnetoelectric (ME) coupling. Herein, electric field (E-field) tuning magnetism, especially the surface spin wave, is accomplished in Ni/0.7Pb(Mg_(1/3)Nb_(2/3))O_(3)-0.3PbTiO_(3) (PMN-PT) multiferroic heterostructures. The Kerr signal (directly proportional to magnetization) changes of Ni film are observed when direct current (DC) or alternative current (AC) voltage is applied to PMN-PT substrate, where the signal can be modulated breezily even without extra magnetic field (H-field) in AC-mode measurement. Deserved to be mentioned, a surface spin wave switch of “1” (i.e., “on”) and “0” (i.e., “off”) has been created at room temperature upon applying an E-field. In addition, the magnetic anisotropy of heterostructures has been investigated by E-field-induced ferromagnetic resonance (FMR) shift, and a large 490 Oe shift of FMR is determined at the angle of 45° between H-field and heterostructure plane.

关键词： spin dynamics multiferroic heterostructure non-volatile magnetic anisotropy spin wave switch

Colorimetric-assisted photoelectrochemical sensing for dual-model detection of sialic acid via oxidation-power mediator integration

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Chinese Chemical Letters 2023年第3期34卷 269-273页

作者： Yuanyuan Cheng Rong-mei Kong Wenao hu Xiaoxia Tian Lingdong Zhang Lian Xia Fengli Qu School of Chemistry and Chemical Engineering Qufu Normal UniversityQufu 273165China

Development of sensitive and accurate methods for sialic acid(SA) determination is of great significance in early cancer ***,a colorimetric-assisted Photoelectrochemical(PEC) sensor was constructed for SA detection based on the two pairs of cis-diol groups in SA *** the specific recognition of SA via the two pairs of cis-diol groups,the prepared gold-modified Bi_(2)S_(3)(AuNPs@Bi_(2)S_(3)) and metal organic framework(Au@PCN-224) were introduced to the electrode and formed a sandwich *** on the properties of inert electroconductivity and nanozyme of the PCN-224,dual-readout of photocurrent and visualization was achieved with the presence of 3',3',5',5'-tetramethylbenzidine(TMB).Moreover,to intensify the visualization signal,Ce^(3+) was employed as the mediator to boost the catalysis capability by transferring energy from PCN-224 surface to the whole *** the unique SA recognition and the mediation of Ce^(3+),both the photocurrent and the visualization signals sensitively responded with the SA concentration *** present method showed greatly high sensitivity,selectivity and accuracy for SA detection with a limit of detection of 1.44μmol/L and a wide linear range of 5-1000μmol/*** method provided a new promising platform for SA detection and a potential strategy for design of novel biosensors with dual-model readout.

关键词： Sialic acid Photoelectrochemical sensor Visualization Metal organic frameworks Dual-mode readout

Ultrathin, Lightweight, and Flexible CNT Buckypaper Enhanced Using MXenes for Electromagnetic Interference Shielding

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Nano-Micro Letters 2021年第4期13卷 208-220页

作者： Rongliang Yang Xuchun Gui Li Yao Qingmei hu Leilei Yang Hao Zhang Yongtao Yao hui mei Zikang Tang State Key Laboratory of Optoelectronic Materials and Technologies School of Electronics and Information TechnologySun Yat-Sen UniversityGuangzhou 510275People’s Republic of China Science and Technology on Thermostructural Composite Materials Laboratory School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072ShaanxiPeople’s Republic of China Instrumental Analysis and Research Center(IARC) Sun Yat-Sen UniversityGuangzhou 510275People’s Republic of China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080People’s Republic of China Institute of Applied Physics and Materials Engineering University of MacaoTaipa 999078MacaoPeople’s Republic of China

Lightweight,flexibility,and low thickness are urgent requirements for next-generation high-performance electromagnetic interference(EMI)shielding materials for catering to the demand for smart and wearable electronic *** several efforts have focused on constructing porous and flexible conductive films or aerogels,few studies have achieved a balance in terms of density,thickness,flexibility,and EMI shielding effectiveness(SE).Herein,an ultrathin,lightweight,and flexible carbon nanotube(CNT)buckypaper enhanced using MXenes(Ti3C2Tx)for high-performance EMI shielding is synthesized through a facile electrophoretic deposition *** obtained Ti3C2Tx@CNT hybrid buckypaper exhibits an outstanding EMI SE of 60.5 dB in the X-band at 100μ*** hybrid buckypaper with an MXene content of 49.4 wt%exhibits an EMI SE of 50.4 dB in the X-band with a thickness of only 15μm,which is 105%higher than that of pristine CNT ***,an average specific SE value of 5.7×10^(4) dB cm^(2) g^(−1) is exhibited in the 5-μm hybrid ***,this assembly process proves promising for the construction of ultrathin,flexible,and high-performance EMI shielding films for application in electronic devices and wireless communications.

关键词： Carbon nanotube MXene Buckypaper Electromagnetic interference shielding

Chewing substances with or without tobacco and risk of cardiovascular disease in Asia:a meta-analysis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第9期11卷 681-689页

作者： Li-na ZHANG Yun-mei YANG Zhe-rong XU Qi-feng GUI Qin-qing hu Department of Gerontology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Department of Nephrology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective:To assess whether people who ever use any form of chewing substance in Asia are at increased risk of cardiovascular disease(CVD).Methods:PubMed and ISI Web of Science were searched for relevant studies,with no limitation on language or study *** were included if they provided quantitative estimate of the association between ever use of chewing substance and the occurrence of *** authors independently implemented inclusion criteria,abstracted study characteristics,and performed *** relative risks were estimated on the basis of a random effect *** used Q statistic and Egger's test to examine heterogeneity across studies and potential publication bias,***:Eight eligible studies were *** relative risk of CVD for ever using chewing substances with or without tobacco was 1.26(95% confidence interval(CI) 1.12-1.40),which was unchanged when restricted to cohort studies [1.25(1.08-1.42)] or cohort studies in Taiwan [1.31(1.12-1.51)].The summary relative risk for ischemic heart disease was 1.27(1.02-1.52),and was lowered to 1.26(0.85-1.67) after exclusion of a cross-sectional *** overall relative risk for cerebrovascular disease was 1.32(1.08-1.56).On the basis of the Taiwan data,the summary relative risk of CVD for betel(Areca catechu) chewing was 1.30(1.17-1.44).Data on dose-response were limited to betel chewing in Taiwan,suggesting a relationship between risk of CVD and cumulative *** large cohorts in Taiwan reported a greater risk of CVD with betel chewing than with ***:An association was detected between betel chewing with or without tobacco and the risk of *** chewing may impose a greater CVD risk than *** effort is needed in developing betel chewing cessation *** relationship between betel chewing and subgroups of CVD requires further investigation.

关键词： Cardiovascular disease Areca catechu Betel quid Chewing tobacco Relative risk Meta-analysis

肺癌胸腔镜肺叶切除术后不同药物镇痛效果的随机对照试验

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中国胸心血管外科临床杂志 2017年第11期24卷 830-834页

作者：林琳戢艳丽车国卫牛玲莉王明铭李霞廖虎杨梅四川大学华西医院胸外科成都610041

目的探讨肺癌患者胸腔镜肺叶切除术后分别应用帕瑞昔布钠及地佐辛镇痛的不良反应及效果。方法纳入2015年8月至2016年1月四川大学华西医院胸外科连续收治的行胸腔镜肺叶切除术的非小细胞肺癌患者90例,用随机数字表将患者分为帕瑞昔布钠组... 详细信息

目的探讨肺癌患者胸腔镜肺叶切除术后分别应用帕瑞昔布钠及地佐辛镇痛的不良反应及效果。方法纳入2015年8月至2016年1月四川大学华西医院胸外科连续收治的行胸腔镜肺叶切除术的非小细胞肺癌患者90例,用随机数字表将患者分为帕瑞昔布钠组(PG组,43例)和地佐辛组(DG组,47例)。分析两组患者术后不良反应、疼痛评分、部位和性质。结果 PG组术后早期恶心、呕吐及腹胀发生率(9.30%,2.33%,13.95%)均低于DG组(25.53%,17.02%,40.43%),且差异有统计学意义(P=0.046,P=0.032,P=0.009)。PG组术后静息状态下12 h、24 h、48 h和72 h镇疼效果(2.56±0.96,2.47±0.96,1.93±0.99,0.98±1.24)均显著优于DG组(4.00±1.60,3.62±1.48,3.36±1.55,2.47±1.78,P=0.000,P=0.000,P=0.000,P=0.002)。同时术后各个时间段咳嗽时镇疼作用在PG组也均优于DG组。两组患者术后疼痛最常见部位均依次是引流管口、手术切口及胸壁;术后疼痛性质均依次是胀疼、刺疼及麻木。结论肺癌患者行胸腔镜肺叶切除术后镇疼应用帕瑞昔布钠不良反应发生率低且效果好。

关键词：胸腔镜肺叶切除帕瑞昔布钠地佐辛肺癌

医院感染实时监控系统病例预警策略的评价研究

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中国感染控制杂志 2019年第4期18卷 326-330页

作者：姚希贾建侠赵艳春任军红赵秀莉胡美华张然彭雪儿李六亿北京大学第一医院感控处北京100034

目的通过评价医院感染实时监控系统(简称"院感系统")病例预警策略的准确性和效率,为预警策略改进提出科学建议。方法通过调查某三级甲等综合医院2017年全年院感系统产生的医院感染预警信息及最终确认情况,计算医院感染预警灵敏度、医院... 详细信息

目的通过评价医院感染实时监控系统(简称"院感系统")病例预警策略的准确性和效率,为预警策略改进提出科学建议。方法通过调查某三级甲等综合医院2017年全年院感系统产生的医院感染预警信息及最终确认情况,计算医院感染预警灵敏度、医院感染预警阳性预测值和感染预警阳性预测值,评价其准确性及效率。结果该院2017年确认的医院感染832例次,其中院感系统有效预警的医院感染715例次,灵敏度为85.94%。全年院感系统共预警8 468例,其中感染病例为2 817例,感染病例数预警阳性预测值为33.27%,医院感染病例为772例,医院感染病例数预警阳性预测值为9.12%。全年院感系统共预警14 857条,其中确认为感染的4 135条,感染预警阳性预测值为27.83%,确认为医院感染的1 199条,医院感染预警阳性预测值为8.07%。结论院感系统是识别医院感染病例的重要技术手段,在病例识别的特异性及效率上还有待提高,另外预警感染高风险病例能力还需加强。

关键词：医院感染实时监控系统预警准确性灵敏度阳性预测值诊断效能

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羊乳母乳化及主要活性成分研究进展

乳业科学与技术 2024年第4期47卷 38-46页

作者：梅芷晴马浩睿刘永峰胡坚舒琴陕西师范大学食品工程与营养科学学院陕西西安710119 西安喜洋洋生物科技有限公司陕西西安710089

羊乳具有很高的营养价值,含有丰富的蛋白质、脂肪、糖类、维生素和矿物质成分,且具有易消化、低致敏性、改善肠道、降胆固醇、抗氧化等功能特性,是成分最接近母乳的乳。为推动羊乳母乳化的研究发展,本文对比羊乳、牛乳和母乳中的营养成... 详细信息

羊乳具有很高的营养价值,含有丰富的蛋白质、脂肪、糖类、维生素和矿物质成分,且具有易消化、低致敏性、改善肠道、降胆固醇、抗氧化等功能特性,是成分最接近母乳的乳。为推动羊乳母乳化的研究发展,本文对比羊乳、牛乳和母乳中的营养成分含量和组成,阐释羊乳母乳化的理论基础和可行性,并对羊乳中主要活性物质(乳清蛋白、酪蛋白、低聚糖)的功能特性及分离技术进行综述,为羊乳母乳化的推广及其在婴幼儿配方乳粉中的应用提供科学依据。

关键词：羊乳母乳化乳清蛋白酪蛋白低聚糖分离技术