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Chemical Research in Chinese Universities 2007年第2期23卷 143-147页

作者： CHEN Jian-guo CHEN neng-wu CHEN Shao-hong LIN Li zhong ying-ying Department of Chemistry Xixi Campus Zhejiang University Hangzhou 310028 P. R. China Ningbo Entry-Exit Inspection and Quarantine Bureau Ningbo 315012 P. R. China

A novel approach was developed for the determination of ultratrace amounts of copper in water samples by using electrothermal atomic absorption spectrometry （ETAAS） after cloud point extraction （ CPE ）. 1-（ 2-Pyridylazo ） -2- naphthol was used as the chelating reagent and Triton X-114 as the mieellar-forming surfactant. CPE was conducted in a pH 8. 0 medium at 40 ℃ for 10 rain. After the separation of the phases by contrifugafion, the surfactant-rieh phase was diluted with 1 mL of a methanol solution of 0. 1 mol/L HNO3. Then 20μL of the diluted surfactant-rieh phase was injected into the graphite furnace for atomization in the absence of any matrix modifier. Various experimental conditions that affect the extraction and atomization processes were optimized. A detection limit of 5 ng/L was obtained after preconeentration. The linear dynamic range of the copper mass concentration was found to be 0-2.0 ng/mL, and the relative standard deviation was found to be less than 3. 1% for a sample containing 1.0 ng/mL Cu （ Ⅱ ）. This developed method was successfully applied to the determination of uhratraee amounts of Cu in drinking water, tap water, and seawater samples.

关键词： Cloud point extraction Preconeentration Electrothermal atomic absorption spectrometry Copper( Ⅱ) Water analysis

Novel additives for the separation of organic acids by ion-pair chromatography

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Chinese Chemical Letters 2010年第4期21卷 453-456页

作者： zhong, ying ying Zhou, Wen Fang Hu, Zhen Zhen Chen, Mei Lan Zhu, Yan Zhejiang Univ Dept Chem Hangzhou 310028 Peoples R China Zhejiang Shuren Univ Biol & Environm Engn Coll Hangzhou 310015 Zhejiang Peoples R China

This paper proposes the use of novel surfactant additives for the separation of organic acids by ion-pair chromatography and studies the influences of surfactants on the chromatographic separation *** have been carried out on both silica gel matrix and polymer supporters in order to compare the two ordinary kinds of stationary phases,and the phenomenon is similar. Separation is based on differences in the stabilities of analyte-additive complexes in *** times of analytes can ...

关键词： Organic acids Ion-pair chromatography Surfactant Mobile phase additives

接触界面微通道内纳米流体流动及传热模拟研究

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贵州工程应用技术学院学报 2024年第3期42卷 35-43页

作者：周雄朱世琰钟莹莹方丽萍赵伟东北部湾大学石油与化工学院广西钦州535011 贵州工程应用技术学院土木建筑工程学院贵州毕节551700

基于计算流体力学的数值仿真方法,对Al_(2)O_(3)-水纳米流体在切削接触界面微通道的层流流动与传热开展了研究,对比分析了在不同的体积分数和雷诺数下纳米流体的强制对流换热特性。结果表明:流体中纳米颗粒的加入对切削接触界面微通道... 详细信息

基于计算流体力学的数值仿真方法,对Al_(2)O_(3)-水纳米流体在切削接触界面微通道的层流流动与传热开展了研究,对比分析了在不同的体积分数和雷诺数下纳米流体的强制对流换热特性。结果表明:流体中纳米颗粒的加入对切削接触界面微通道的流速影响很小,但改善了流体的导热系数,造成纳米流体与壁面的对流换热效果明显,且纳米颗粒的体积分数越大,换热效果越好;换热系数和努塞尔数在雷诺数较小时(Re=0~100)随雷诺数快速增加,在雷诺数较大时(Re=100~500)随雷诺数缓慢增加,高雷诺数时的换热效果明显高于低雷诺数时;研究范围内,在相同的纳米颗粒浓度下,流体对流换热系数增加的幅度要大于纳米流体导热系数的增加幅度。

关键词：微通道纳米流体数值仿真换热系数努塞尔数

Clathrate metal superhydrides under high-pressure conditions: enroute to room-temperature superconductivity

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National Science Review 2024年第7期11卷 33-46页

作者： ying Sun Xin zhong Hanyu Liu Yanming Ma Key Laboratory of Material Simulation Methods&Software of Ministry of Education College of Physics Jilin University State Key Laboratory of Superhard Materials College of PhysicsJilin University International Center of Future Science Jilin University

Room-temperature superconductivity has been a long-held dream of mankind and a focus of considerable interest in the research field of superconductivity. Significant progress has recently been achieved in hydrogen-based superconductors found in superhydrides（hydrides with unexpectedly high hydrogen contents） that are stabilized under high-pressure conditions and are not capturable at ambient *** particular interest is the discovery of a class of best-ever-known superconductors in clathrate metal superhydrides that hold the record for high superconductivity(e.g. Tc= 250–260 K for LaH10) among known superconductors and have great promise to be those that realize the long-sought room-temperature superconductivity. In these peculiar clathrate superhydrides, hydrogen forms unusual ‘clathrate’ cages containing encaged metal atoms, of which such a kind was first reported in a calcium hexa-superhydride（CaH6） showing a measured high Tcof 215 K under a pressure of 170 GPa. In this review, we aim to offer an overview of the current status of research progress on the clathrate metal superhydride superconductors,discuss the superconducting mechanism and highlight the key features（e.g. structure motifs, bonding features, electronic structure, etc.） that govern the high-temperature superconductivity. Future research direction along this line to find room-temperature superconductors will be discussed.

关键词： clathrate superhydrides high-temperature superconductivity high-pressure conditions crystal structure prediction

A Dielectric Ink Combining Acrylate and Cyanate Moieties for Inkjet 3D Printing with Good Thermal Stability

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Chinese Journal of Polymer Science 2024年第6期42卷 766-774页

作者： Yi-Xuan Li Liang-ying Wu Yan Yang Yao-zhong Lu zhong-ying Ji Yu-Xiong Guo Xiao-Long Wang Qiao-Sheng Pu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsLanzhou730000China Lanzhou Traditional Chinese Medicine Hospital of Orthopedics and Traumatology Lanzhou730000China Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai Yantai Zhongke Research Institute of Advanced Materials and Green Chemical EngineeringYantai264006China

Inkjet 3D printing has potential in the additive manufacturing of electronic circuits and ***,inks that can be used for printing layers with T5%>300℃ or hardness>200 MPa have been rarely *** ester(CE)polymers have excellent thermal stability,high strength,and low shrinkage compared to other common dielectric inks for inkjet 3D printing,but cannot be quickly shaped by ultraviolet(UV)irradiation or thermal *** CEs with UV-curable monomers may be a possible way to accelerate crosslinking,but there are challenges from the adverse effects of the dilution of both *** this study,dielectric inks with acrylate and cyanate moieties were *** low viscosity and surface tension of the CE precursor(Bisphenol E cyanate ester)were combined with photocurable acrylate diluent monomers and cross-linker to realize an ink suitable for inkjet 3D *** internal dual three-dimensional cross-linked network structure resin was prepared by a combination of photocuring and thermal curing with T5%up to 326.69℃,hardness up to 431.84 MPa,dielectric constant of 2.70 at 8 GHz,and shrinkage of 1.64%.The developed dielectric inks can be applied to the 3D printing of printed circuit boards and other electronic devices that require dielectric properties.

关键词： Inkjet printing Cyanate ester resin 3D doubly cross-linked network Good thermal stability

Improvement of mechanical properties and investigation of strengthening mechanisms on the Ti_(3)AlC_(2) ceramic with nanosized WC addition

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Journal of Advanced Ceramics 2024年第6期13卷 861-876页

作者： Yi zhong ying Liu Qinkai Jiang Na Jin Zifeng Lin Jinwen Ye School of Materials Science&Engineering Sichuan UniversityChengdu 610065China Yibin R&D Park Yibin Industrial Technology Research InstituteSichuan UniversityYibin 644005China

Ti_(3)AlC_(2) (TAC) has great potential for use as an ablation material in aerospace applications due to its great oxidation/ablation resistance, but its high-temperature strength and thermal shock resistance still have much room for simultaneous improvement under fast temperature variation conditions. Herein, we used Ti_(3)AlC_(2) and WC powders as raw materials and successfully fabricated textured (Ti,W)_(3)AlC_(2) ceramic with small amounts of TiC and Al_(2)O_(3), and room temperature mechanical properties such as flexural strength (1146±46.9 MPa), fracture toughness (11.78±0.44 MPa·m^(1/2)), and hardness (5.81±0.11 GPa) at 5 wt% WC addition were achieved. The high-temperature strength of the ceramic was significantly improved, and better thermal shock resistance from 298 to 1173 K was simultaneously acquired together with the regulation of the elastic modulus, thermal conductivity, and thermal expansion coefficient, providing (Ti,W)_(3)AlC_(2) with more possibilities for fast-temperature variation applications. Strengthening and toughening mechanisms were proposed. Scanning transmission electron microscopy high-angle annular dark-field imaging (STEM-HADDF) showed that W randomly replaced the Ti1 and Ti2 sites of Ti_(3)AlC_(2), providing a good reference for establishing crystal models, and further density functional theory (DFT) calculations based on these models indicated a higher fracture energy of (Ti,W)_(3)AlC_(2) along different crystal planes, providing superior resistance to transgranular fracture;a lower mismatch degree of (Ti,W)_(3)AlC_(2)/Al_(2)O_(3) resulted in stronger interface bonding, resulting in greater resistance to intergranular fracture as well as more balanced stress distributions at different interfaces.

关键词： mechanical properties solid solution MAX phase transmission electron microscopy(TEM) ceramic atomic structure

Computed tomography-based radiomics diagnostic approach for differential diagnosis between early-and late-stage pancreatic ductal adenocarcinoma

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1256-1267页

作者： Shuai Ren Li-Chao Qian ying-ying Cao Marcus J Daniels Li-Na Song ying Tian zhong-Qiu Wang Department of Radiology Jiangsu Province Hospital of Chinese MedicineAffiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Geratology Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese MedicineNanjing 210022Jiangsu ProvinceChina Department of Radiology NYU Langone HealthNew YorkNY 10016United States

BACKGROUND One of the primary reasons for the dismal survival rates in pancreatic ductal adenocarcinoma(PDAC)is that most patients are usually diagnosed at late *** is an urgent unmet clinical need to identify and develop diagnostic methods that could precisely detect PDAC at its earliest *** A total of 71 patients with pathologically proved PDAC based on surgical resection who underwent contrast-enhanced computed tomography(CT)within 30 d prior to surgery were included in the *** staging was performed in accordance with the 8th edition of the American Joint Committee on Cancer staging *** features were extracted from the region of interest(ROI)for each patient using Analysis Kit *** most important and predictive radiomics features were selected using Mann-Whitney U test,univar-iate logistic regression analysis,and minimum redundancy maximum relevance(MRMR)*** forest(RF)method was used to construct the radiomics model,and 10-times leave group out cross-validation(LGOCV)method was used to validate the robustness and reproducibility of the *** A total of 792 radiomics features(396 from late arterial phase and 396 from portal venous phase)were extracted from the ROI for each patient using Analysis Kit *** most important and predictive features were selected using Mann-Whitney U test,univariate logistic regression analysis,and MRMR *** method was used to construct the radiomics model with the nine most predictive radiomics features,which showed a high discriminative ability with 97.7%accuracy,97.6%sensitivity,97.8%specificity,98.4%positive predictive value,and 96.8%negative predictive *** radiomics model was proved to be robust and reproducible using 10-times LGOCV method with an average area under the curve of 0.75 by the average performance of the 10 newly built *** The radiomics model based on CT could serve as a promising non-invasive method in differential diag

关键词： Pancreatic ductal adenocarcinoma Radiomics Computed tomography American Joint Committee on Cancer staging

Highly Aligned Graphene Aerogels for Multifunctional Composites

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Nano-Micro Letters 2024年第6期16卷 276-342页

作者： ying Wu Chao An Yaru Guo Yangyang Zong Naisheng Jiang Qingbin Zheng zhong‑Zhen Yu Beijing Advanced Innovation Center for Materials Genome Engineering School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004People’s Republic of China School of Science and Engineering The Chinese University of Hong KongShenzhenShenzhenGuangdong 518172People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Stemming from the unique in-plane honeycomb lattice structure and the sp^(2)hybridized carbon atoms bonded by exceptionally strong carbon–carbon bonds,graphene exhibits remarkable anisotropic electrical,mechanical,and thermal *** maximize the utilization of graphene’s in-plane properties,pre-constructed and aligned structures,such as oriented aerogels,films,and fibers,have been *** unique combination of aligned structure,high surface area,excellent electrical conductivity,mechanical stability,thermal conductivity,and porous nature of highly aligned graphene aerogels allows for tailored and enhanced performance in specific directions,enabling advancements in diverse *** review provides a comprehensive overview of recent advances in highly aligned graphene aerogels and their *** highlights the fabrication methods of aligned graphene aerogels and the optimization of alignment which can be estimated both qualitatively and *** oriented scaffolds endow graphene aerogels and their composites with anisotropic properties,showing enhanced electrical,mechanical,and thermal properties along the alignment at the sacrifice of the perpendicular *** review showcases remarkable properties and applications of aligned graphene aerogels and their composites,such as their suitability for electronics,environmental applications,thermal management,and energy *** and potential opportunities are proposed to offer new insights into prospects of this material.

关键词： Highly aligned graphene aerogels Quantitative characterization of alignment Multifunctional composites Anisotropic properties Multifunctional applications

Non-contact and full-field online monitoring of curing temperature during the in-situ heating process based on deep learning

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Advances in Manufacturing 2024年第1期12卷 167-176页

作者： Qiang-Qiang Liu Shu-Ting Liu ying-Guang Li Xu Liu Xiao-zhong Hao College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing211816People’s Republic of China

Online monitoring of the curing temperature field is essential to improving the quality and efficiency of the manufacturing process of composite *** embedded sensor-based technologies have difficulty monitoring the full temperature field or have to introduce heterogeneous items that could have an undesired impact on the *** this paper,a non-contact,full-field monitoring method based on deep learning that predicts the internal temperature field of composite parts in real time using surface temperature measurements of auxiliary materials is *** the proposed method,an average temperature monitoring accuracy of 97%is achieved in various heating *** addition,this method also demonstrates satisfying feasibility when a stronger thermal barrier covers the *** method was experimentally validated during the self-resistance electric heating process,in which the monitoring accuracy reached 93.1%.This method can potentially be applied to automated manufacturing and process control in the composites industry.

关键词： Online monitoring Curing temperature field Deep learning(DL) In-situ heating

侵袭性高黏液型肺炎克雷伯菌感染的临床和分子特征研究

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广东医科大学学报 2024年第2期42卷 157-161,168页

作者：刘志云梁雪雁曹海燕李璐李格格钟莹莹冼志丽吴显劲汕头大学医学院广东汕头515041 惠州市中心人民医院广东惠州516001 广东医科大学广东东莞523808 嘉应医学院广东梅州514031

目的分析引起侵袭性高黏液型肺炎克雷伯菌(HMVKP)感染患者的临床和分子特征,为侵袭性高黏液型肺炎克雷伯菌感染的精准诊断和临床抗感染治疗提供依据。方法分析临床分离的侵袭性高黏液型肺炎克雷伯菌感染患者临床资料,利用PCR方法对菌株... 详细信息

目的分析引起侵袭性高黏液型肺炎克雷伯菌(HMVKP)感染患者的临床和分子特征,为侵袭性高黏液型肺炎克雷伯菌感染的精准诊断和临床抗感染治疗提供依据。方法分析临床分离的侵袭性高黏液型肺炎克雷伯菌感染患者临床资料,利用PCR方法对菌株荚膜血清型、毒力基因及耐药基因检测进行分子特征研究。结果96株侵袭性肺炎克雷伯菌感染的菌株中64株为HMVKP,脓液标本在HMVKP组标本中的占比(32.8%)最大;在HMVKP组中共检出4例产ESBL菌株及2株耐碳青霉烯类药物菌株;HMVKP菌株的荚膜血清型以K1(40.6%)和K2(29.7%)为主,毒力基因以peg344、iucA和iroB携带率最高。HMVKP与N-HMVKP菌株的7个毒力基因(peg344、rmpA、rmpA2、magA、iucA、iroB与kfu)差异均有统计学意义(P<0.05)。结论K1和K2是本地区侵袭性感染HMVKP最常见的荚膜血清型,peg344、iucA、iroB、rmpA是HMVKP主要的毒力基因,现在已出现合并多重耐药尤其是耐碳青霉烯类抗生素的HMVKP菌株,应重视。

关键词：肺炎克雷伯菌高黏液型侵袭性感染耐药性毒力基因