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Growth of TlBa_2Ca_2Cu_3O_9 Epitaxial Thin Films by Two-Step Method in Argon

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Chinese Physics Letters 2019年第5期36卷 79-83页

作者： Jian Xing Li-Tian Wang Xiao-Xin Gao Xue-Lian Liang kai-yong he Ting Xue Sheng-Hui Zhao Jin-Li Zhang Ming he Xin-Jie Zhao Shao-Lin Yan Pei Wang Lu Ji College of Electronic Information and Optical Engineering Nankai UniversityTianjin 300350 Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology Tianjin 300350 Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin Tianjin 300350 Beijing Institute of Radio Measurement Beijing 100854

TlBa_2 Ca_2 Cu_3 O_9(Tl-1223) films have promising applications due to their high critical temperature and strong magnetic flux pinning. Nevertheless, the preparation of pure phase Tl-1223 film is still a challenge. We successfully fabricate Tl-1223 thin films on LaAlO_3(001) substrates using dc magnetic sputtering and a post annealing two-step method in argon atmosphere. The crystallization temperature of Tl-1223 films in argon is reduced by 100℃ compared to that in oxygen. This greatly reduces the volatilization of Tl and improves the surface morphology of films. The lower annealing temperature can effectively improve the repeatability of the Tl-1223 film preparation. In addition, pure Tl-1223 phase can be obtained in a broad temperature zone,from 790℃ to 830℃. In our study, the films show homogenous and dense surface morphology using the presented method. The best critical temperature of Tl-1223 films is characterized to be 110 K, and the critical current J_c(77 K, 0 T) is up to 2.13 × 106 A/cm^2.

关键词： Ba Cu Ca

基于拉曼光谱技术的茶树叶片中类胡萝卜素含量的无损快速检测

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光谱学与光谱分析 2017年第11期37卷 3465-3470页

作者：李晓丽许凯雯何勇浙江大学生物系统工程与食品科学学院浙江杭州310058

叶片中类胡萝卜素是植被环境胁迫、光合能力和植被发育阶段的指示器。基于叶片的原位拉曼光谱响应特性对龙井43叶片的类胡萝卜素含量进行了研究,建立了两者之间的定量模型。本文共对315个龙井43叶片样本进行了拉曼光谱采集和分光光度检... 详细信息

叶片中类胡萝卜素是植被环境胁迫、光合能力和植被发育阶段的指示器。基于叶片的原位拉曼光谱响应特性对龙井43叶片的类胡萝卜素含量进行了研究,建立了两者之间的定量模型。本文共对315个龙井43叶片样本进行了拉曼光谱采集和分光光度检测。为排除检测过程中受噪声、基线漂移等因素的干扰,运用和比较了五种光谱数据预处理方法提取原始拉曼光谱中与茶叶中类胡萝卜素含量有关的有效信息。基于预处理后的数据建立了偏最小二乘(PLS)回归模型,拉曼光谱与类胡萝卜素含量的建模集和预测集的相关系数(r)分别为0.817和0.786。为进一步研究类胡萝卜素的拉曼光谱响应机理,本文采用连续投影算法(SPA)优选了17个拉曼特征波数建立相应的特征波数模型,模型的建模集和预测集的相关系数(r)分别为0.808和0.777。根据已建立的模型,探究了茶树四个不同叶位的叶片类胡萝卜素含量的变化。发现茶树叶片随着叶龄的增加,类胡萝卜素浓度呈先增后减的趋势。以第2位叶的类胡萝卜素含量最高。进一步验证了模型的可行性以及探索了将该模型应用于茶树叶片树龄和叶位探测的可能性。采用拉曼光谱技术可以实现茶树叶片中类胡萝卜素含量的原位、无损、定量检测。

关键词：拉曼光谱类胡萝卜素定量分析模型评价特征提取

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询价对象间关系网络的IPO定价后果研究

管理科学学报 2017年第7期20卷 57-67页

作者：郑凯阮永平何雨晴华东理工大学商学院上海200237 中国建设银行上海市分行上海200120

本文基于资本市场主体关系网络的研究视角,检验了询价对象间关系网络作用于IPO定价的机理和后果,结果表明询价对象间关系网络的强度和性质通过影响询价对象个体报价行为显著作用于IPO定价.研究发现,询价对象个体间关联程度越高,协同低... 详细信息

本文基于资本市场主体关系网络的研究视角,检验了询价对象间关系网络作用于IPO定价的机理和后果,结果表明询价对象间关系网络的强度和性质通过影响询价对象个体报价行为显著作用于IPO定价.研究发现,询价对象个体间关联程度越高,协同低报价行为越严重;询价对象整体关联程度越高,IPO定价越低;QFII参与询价没有弱化反而强化了询价对象间关系网络强度对询价对象协同低报价行为和IPO低定价的作用效果.本文研究发现IPO定价会受到询价对象间关系网络的影响,拓展了资本市场关系网络研究范围,也为尝试利用市场机制而不是仅依靠行政力量解决我国IPO市场潜在的高定价问题提供理论依据.

关键词： IPO 询价对象关系网络 QFII

基于变邻域粒子群算法的铁水硅含量稳定性分析

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钢铁研究学报 2017年第2期29卷 87-92,97页

作者：杨凯金永龙何志军辽宁科技大学辽宁鞍山114051 宝钢发展公司上海201900

影响高炉铁水硅含量的因素往往复杂多变,影响程度不一。采用鱼骨分析法收集所有可能对硅含量产生影响的因素,经过相关分析和特征选择,最终选取6个参数作为模型的输入参数。采用改进的粒子群优化算法对支持向量机(SVM)中的参数进行优化,... 详细信息

影响高炉铁水硅含量的因素往往复杂多变,影响程度不一。采用鱼骨分析法收集所有可能对硅含量产生影响的因素,经过相关分析和特征选择,最终选取6个参数作为模型的输入参数。采用改进的粒子群优化算法对支持向量机(SVM)中的参数进行优化,提出基于变邻域粒子群(VNPSO)优化SVM的铁水硅含量预测模型。通过钢厂的实际生产数据进行验证,平均相对误差达到0.69%,平均绝对误差达到3.4×10^(-3),模型具有很高的预测精度。同时,绘制铁水中硅含量控制图,分析硅含量波动情况,并依此模型给出硅含量稳定性控制措施。

关键词：炼铁硅含量智能优化仿真

Characteristics of gut microbiota dysbiosis in patients with colorectal polyps

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 13-21页

作者： Xian-Rong Wu Xiao-Hong he yong-Fang Xie School of Life health Information Science and Engineering Chongqing Post and Communications UniversityChongqing 400065China

This editorial,inspired by a recent study published in the World Journal of Gastrointestinal Oncology,covers the research findings on microbiota changes in various *** recurrent colorectal polyps,the abundances of Klebsiella,Parvimonas,and Clostridium increase,while those of Bifidobacterium and Lactoba-cillus *** dysbiosis may promote the formation and recurrence of *** microbial changes have also been observed in colorectal cancer,inflammatory bowel disease,autism spectrum disorder,and metabolic syndrome,indicating the role of increased pathogens and decreased probiotics in these *** the gut microbiota,particularly by increasing probiotic levels,may help prevent polyp recurrence and promote gut *** microbial intervention strategy holds promise as an adjunctive treatment for patients with colorectal polyps.

关键词： Recurrent colorectal polyps Gut microbiota dysbiosis Klebsiella Probiotics Intestinal inflammation Microbial intervention strategy

Exploring the performance of large language models on hepatitis B infection-related questions:A comparative study

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World Journal of Gastroenterology 2025年第3期31卷 103-112页

作者： Yu Li Chen-kai Huang Yi Hu Xiao-Dong Zhou Cong he Jia-Wei Zhong Department of Gastroenterology Jiangxi Provincial Key Laboratory of Digestive DiseasesJiangxi Clinical Research Center for GastroenterologyDigestive Disease HospitalThe First Affiliated HospitalJiangxi Medical CollegeNanchang UniversityNanchang 330006Jiangxi ProvinceChina HuanKui Academy Nanchang UniversityNanchang 330006Jiangxi ProvinceChina

BACKGROUND Patients with hepatitis B virus(HBV)infection require chronic and personalized care to improve *** language models(LLMs)can potentially provide medical information for *** To examine the performance of three LLMs,ChatGPT-3.5,ChatGPT-4.0,and Google Gemini,in answering HBV-related *** LLMs’responses to HBV-related questions were independently graded by two medical professionals using a four-point accuracy scale,and disagreements were resolved by a third *** question was run three times using three *** was assessed via the Gunning Fog index and Flesch-Kincaid grade *** Overall,all three LLM chatbots achieved high average accuracy scores for subjective questions(ChatGPT-3.5:3.50;ChatGPT-4.0:3.69;Google Gemini:3.53,out of a maximum score of 4).With respect to objective questions,ChatGPT-4.0 achieved an 80.8%accuracy rate,compared with 62.9%for ChatGPT-3.5 and 73.1%for Google *** the six domains,ChatGPT-4.0 performed better in terms of diagnosis,whereas Google Gemini demonstrated excellent clinical ***,in the readability analysis,the mean Gunning Fog index and Flesch-Kincaid grade level scores of the three LLM chatbots were significantly higher than the standard level eight,far exceeding the reading level of the normal *** Our results highlight the potential of LLMs,especially ChatGPT-4.0,for delivering responses to HBV-related *** may be an adjunctive informational tool for patients and physicians to improve ***,current LLMs should not replace personalized treatment recommendations from physicians in the management of HBV infection.

关键词： ChatGPT-3.5 ChatGPT-4.0 Google Gemini hepatitis B infection Accuracy

Assessing the corrosion protection property of coatings loaded with corrosion inhibitors using the real-time atmospheric corrosion monitoring technique

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 119-126页

作者： Xiaoxue Wang Lulu Jin Jinke Wang Rongqiao Wang Xiuchun Liu kai Gao Jingli Sun yong Yuan Lingwei Ma Hongchang Qian Dawei Zhang School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beijing Institute of Space Long March Vehicle Beijing 100076China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China Shanghai Spaceflight Precision Machinery Institute Shanghai 201600China

The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal ***,limited studies have applied ACM to the corrosion protection properties of organic *** study compared a bare epoxy coating with one containing zinc phosphate corrosion inhibitors,both applied on ACM sensors,to observe their corrosion protection properties over *** with artificial damage via scratches were exposed to immersion and alternating dry and wet environments,which allowed for monitoring galvanic corrosion currents in *** the corrosion tests,the ACM currents of the zinc phosphate/epoxy coating were considerably lower than those of the blank epoxy *** trend in ACM current variations closely matched the results obtained from regular electrochemical tests and surface *** alignment highlights the potential of the ACM technique in evaluating the corrosion protection capabilities of organic *** with the blank epoxy coating,the zinc phosphate/epoxy coating showed much-decreased ACM current values that confirmed the effective inhibition of zinc phosphate against steel corrosion beneath the damaged coating.

关键词： atmospheric corrosion monitoring technology corrosion inhibitor coating carbon steel corrosion protection

3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration

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Nano-Micro Letters 2025年第2期17卷 18-45页

作者： Ke Yao Gaoying Hong Ximin Yuan Weicheng Kong Pengcheng Xia Yuanrong Li Yuewei Chen Nian Liu Jing he Jue Shi Zihe Hu Yanyan Zhou Zhijian Xie yong he State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Liangzhu Laboratory Zhejiang UniversityHangzhou 310027People’s Republic of China Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province College of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Stomatology Hospital School of StomatologyZhejiang University School of MedicineHangzhou 310027People’s Republic of China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001People’s Republic of China Institute of Digital Medicine Nanjing First HospitalNanjing Medical UniversityNanjing 210006People’s Republic of China

Hydrogel scaffolds have numerous potential applications in the tissue engineering ***,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical *** by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this ***,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent ***,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell ***,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT *** experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.

关键词： 3D printing Tough hydrogel scaffold Functional surface structure Tissue regeneration Biomaterials

An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang kai Zhang Liping Ding Liyun Wu Songfeng E Qian he Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu Jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory