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Strontium chloride-catalyzed one-pot synthesis of 2,3-dihydroquinazolin-4(1H)-ones in protic media

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Chinese Chemical Letters 2011年第12期22卷 1423-1426页

作者： Min Wang Ting Ting zhang yan liang Jing Jing Gao College of Chemistry and Chemical Engineering Bohai University Jinzhou 121000 China

A wide range of mono-and disubstituted 2,3-dihydroquinazolin-4（1H）-ones were obtained in high yields by condensation of isatoic anhydride,aldehydes with ammonium salts or primary amines in the presence of strontium ... 详细信息

关键词： 2 3-Dihydroquinazolin-4(1H)-ones One-pot synthesis Strontium chloride Isatoic anhydride

Pd/AlF3 Catalysts for Catalytic Dehydrofluorination of 1,1,1,3,3-Pentafluoropropane

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Chemical Research in Chinese Universities 2015年第6期31卷 1003-1006页

作者： WANG Fang zhang Wenxia liang yan WANG Yuejuan LU Jiqing LUO Mengfei Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces Institute of Physical Chemistry Zhejiang Normal University Jinhua 321004 P. R. China

A series of Pd/AlF3 catalysts was prepared by an impregnation method and tested for vapor-phase dehy- drofluorination of 1,1,1,3,3-pentafluoropropane（HFC-245fa） to synthesize 1,3,3,3-tetrafluoropropene（HFO-1234ze）. The highest activity was obtained over Pd/AIF3 catalyst containing 1.0%（mass fraction） of Pd, with an HFC-245fa conversion of 79.5% and an HFO-1234ze selectivity of 99.4% after the reaction at 300 ℃ for 100 h. The reactivity was related to the surface acidity, as AlF3 provided active sites for the reaction. With the addition of Pd, the catalyst stability could be significantly improved. Raman spectroscopic and thermal-gravimetric analysis results reveal that there was less carbon deposit on spent Pd/AlF3 catalyst surface because Pd could effectively pyrolyse it. Thus, Pd/AlF3 catalysts were bi-functional for dehydrofluorination of HFC-245fa.

关键词： Pd/AlF3 catalyst Lewis acid Carbon deposit

Epitaxial growth of ultrathin ZrO_2(111) films on Pt(111)

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Chinese Science Bulletin 2011年第6期56卷 502-507页

作者： GAO yan zhang liang PAN YongHe WANG GuoDong XU yang zhang WenHua ZHU JunFa National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei 230029 China

Ordered epitaxial ZrO2 films were grown on Pt(111) and characterized by low energy electron diffraction (LEED), synchrotron radiation photoemission spectroscopy (SRPES) and X-ray photoelectron spectroscopy (XPS). The films were prepared by vapor deposition of zirconium in an O2 atmosphere followed by annealing under ultra high vacuum. At low coverages, the films grew as discontinuous two-dimentional islands with ordered structures. The size and structure of these islands were dependent on the coverage of ZrO2 films. At coverage 6 ML, a continuous ZrO2(111) film was formed with a (1×1) surface LEED pattern coexisting with a (2×2) pattern. These ordered thin ZrO2 films provide good model surfaces of bulk ZrO2 and can be used for further fundamental studies of the surface chemistry of ZrO2 using modern surface science techniques.

关键词：二氧化锆薄膜薄膜外延生长同步辐射光电子能谱超薄有序结构表面图案低能电子衍射化学基础研究

基于RF-WOA-VMD-BiGRU-Attention的神经网络模型在海浪预测中的应用

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科学技术与工程 2024年第7期24卷 2638-2646页

作者：李练兵张燕亮吴伟强魏玉憧李佳根卢盛欣河北工业大学人工智能与数据科学学院天津300130 河北建投海上风电有限公司唐山063000

海上风电场的海况数据极其复杂导致用于海浪高度预测的输入参数极其不稳定,筛选出关键信息,提高输入参数的质量可以极大地提高海浪高度预测的准确性。以乐亭菩提岛风电场近一年的海上数据为基础,构建了一种基于随机森林(random forest, ... 详细信息

海上风电场的海况数据极其复杂导致用于海浪高度预测的输入参数极其不稳定,筛选出关键信息,提高输入参数的质量可以极大地提高海浪高度预测的准确性。以乐亭菩提岛风电场近一年的海上数据为基础,构建了一种基于随机森林(random forest, RF)、鲸鱼优化算法(whale optimization algorithm, WOA)、变分模态分解(variational mode decomposition, VMD)和双向门控循环单元(bidirectional gated recurrent unit, BiGRU)的海浪预测模型。该模型利用随机森林对环境特征等输入变量进行筛选,有效减少数据冗余,然后基于WOA-VMD模型自适应确定最优参数和自适应分解原始序列,提高数据质量并消除数据噪声的干扰。此外,针对海浪预测提出了一种基于注意力机制优化的BiGRU算法,随机森林的注意力机制将为BiGRU的隐藏层状态分配不同的权重,加强关键信息的影响。实验结果表明该模型和其他模型对比,输入质量更高,预测精度更高,拟合程度更准确,对风电场海浪预测有着重大意义。

关键词：海浪预测随机森林鲸鱼优化算法变分模态分解双向门控循环单元注意力机制

Recent progress in Prussian blue electrode for electrochromic devices

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Frontiers in Energy 2024年第2期18卷 160-186页

作者： Yongting zhang Wanzhong LI Hui GONG Qianqian zhang liang yan Hao WANG Key Laboratory for New Functional Materials of the Ministry of Education Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China School of Instrument Science and Engineering Southeast UniversityNanjing 210096China Beijing Aerospace Times Laser Inertial Technology Company Beijing 100094China

Great progress has been made in the electrochromic(EC)technology with potential applications in various *** one of the most promising EC materials,Prussian blue(PB)has attracted great attention due to its excellent EC performance,such as low cost,easy synthesis,rich color states,chemical stability,suitable redox potential,and fast color-switching *** review summarizes the recent progress in PB electrodes and devices,including several typical preparation techniques of PB electrodes,as well as the recent key strategies for enhancing EC performance of PB ***,PB-based electrochromic devices(ECDs)have been widely used in various fields,such as smart windows,electrochromic energy storage devices(EESDs),wearable electronics,smart displays,military camouflage,and other *** opportunities and obstacles are suggested for advancing the development of PB-based *** comprehensive review is expected to offer valuable insights for the design and fabrication of sophisticated PBbased ECDs,enabling their practical integration into realworld applications.

关键词： Prussian blue electrochromism energy storage smart windows

Application of the finite analytic numerical method to a flowdependent variational data assimilation

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Acta Oceanologica Sinica 2024年第3期43卷 30-39页

作者： yan Hu Wei Li Xuefeng zhang Guimei Liu liang zhang Tianjin Key Laboratory for Marine Environmental Research and Service School of Marine Science and TechnologyTianjin UniversityTianjin 300072China School of Marine Science and Technology Tianjin UniversityTianjin 300072China National Marine Environmental Forecasting Center Ministry of Natural ResourcesBeijing 100081China

An anisotropic diffusion filter can be used to model a flow-dependent background error covariance matrix,which can be achieved by solving the advection-diffusion *** of the directionality of the advection term,the discrete method needs to be chosen very *** finite analytic method is an alternative scheme to solve the advection-diffusion *** a combination of analytical and numerical methods,it not only has high calculation accuracy but also holds the characteristic of the auto *** demonstrate its ability,the one-dimensional steady and unsteady advection-diffusion equation numerical examples are respectively solved by the finite analytic *** more widely used upwind difference method is used as a control *** result indicates that the finite analytic method has higher accuracy than the upwind difference *** the two-dimensional case,the finite analytic method still has a better *** the three-dimensional variational assimilation experiment,the finite analytic method can effectively improve analysis field accuracy,and its effect is significantly better than the upwind difference and the central difference ***,it is still a more effective solution method in the strong flow region where the advective-diffusion filter performs most prominently.

关键词： finite analytic method advection-diffusion equation data assimilation flow-dependent

Magnetic resonance imaging combined with serum endolipin and galactagoglobin-3 to diagnose cerebral infarction in the elderly with diabetes mellitus

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World Journal of Diabetes 2024年第7期15卷 1509-1517页

作者： yan-Hui zhang Dong liang Magnetic Resonance Imaging Room Tianjin Huanhu HospitalTianjin 300350China Department of Endocrinology Tianjin First Central HospitalTianjin 300190China

BACKGROUND Magnetic resonance imaging(MRI)combined with serum endothelin and galactagoglobin-3(Gal-3)can improve the clinical diagnosis of diabetes mellitus complicated with cerebral *** To analyze the clinical value of MRI combined with serum endolipin and Gal-3 for the diagnosis of cerebral infarction in the elderly with diabetes *** One hundred and fifty patients with acute cerebral infarction hospitalized between January 2021 and December 2023 were divided into two groups according to comorbid diabetes mellitus,including 62 and 88 cases in the diabetic and nondiabetic cerebral infarction *** samples were collected to detect the expression of serum endolipoxins,and Gal-3,and cranial MRI was performed at *** between the two groups were compared to analyze the diagnostic value of these *** Serum endolipin and Gal-3 expression were higher in the diabetic cerebral infarction group(P<0.05).The arterial wall area,vessel area,normalized wall index,and lumen stenosis rate were higher in the diabetic cerebral infarction group,while the rate of arterial lumen moderate and severe stenosis was 48.39% higher(36.36%,P<0.05).The percentage of large(29.03%)and multiple infarcts(33.87%)in the diabetic cerebral infarction group was higher(13.64% and 20.45%),and the incidence rate of lacunar infarcts was lower(37.10%vs 65.91%)(P<0.05).The total incidence of arterial plaque in patients in the diabetic cerebral infarction group was 96.77% higher(69.32%),while the incidence of necrotic lipid core plaque was 58.06%higher(26.14%)(P<0.05).Receiver operating characteristic curve analysis was performed to assess the diagnosis utility of these *** in combination with serum endoglin and Gal-3 had the highest area under the curve,the Yoden index,sensitivity and specificity(P<0.05).CONCLUSION The expression of serum endolipin and Gal-3 in elderly patients with diabetes mellitus with cerebral infarction showed an eleva

关键词： Endolipin Galectin-3 Magnetic resonance imaging Elderly Diabetes mellitus Cerebral infarction

Evaluating the tumor stratification with a lysosomal pH sensitive-probe by fluorescence lifetime imaging

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Chinese Chemical Letters 2024年第3期35卷 262-267页

作者： Jun yan Xing liang Qian zhang Luolin Wang Weiying Lin Guangxi Key Laboratory of Electrochemical Energy Materials Institute of Optical Materials and Chemical BiologySchool of Chemistry and Chemical EngineeringGuangxi UniversityNanning 530004China

Owing to the anaerobic metabolism in the tumor,abundant acidic metabolites are produced and accumulated in the ***,the cells in different tumor layers are directly linked to the pH ***,due to the lack of robust tools,the high-efficient evaluation of the acidic micro-environment of tumor stratification faces the challenge of accurate *** designed a new pH sensitive fluorescent lifetime probe target to *** we expected,the fluorescence lifetime of PLN possesses a good linear fit to the pH value,which could detect the pH change at a single lysosome level in real time,and then evaluate the different acidity of tumor *** probe PLN is successfully used to evaluate the tumor stratification by fluorescence lifetime imaging microscopy(FLIM)for the first time,which is of great significance in the preoperative diagnosis of clinical tumor treatment or evaluation of drug delivery effect.

关键词： FLIM pH Fluorescence imaging Lysosome Tumor imaging

Hydrogen storage thermodynamics and kinetics of as-cast Ce-Mg-Ni-based alloy

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Journal of Iron and Steel Research International 2024年第3期31卷 752-766页

作者： yan Qi Xin zhang Jun Li Dong-liang Zhao Shi-hai Guo yang-huan zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China China Rare Earth New Material(Weishan)Co..Ltd. Jining 277600ShandongChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina

The reaction kinetics of alloys based on magnesium are known to be greatly improved by the partial substitution of Mg with rare earths and transition metals,particularly *** enhanced superficial hydrogen dissociation rate,the weakened Mg-H bond and the lower activation energy following element replacement are thought to be related to the better *** experimental alloys Ce5Mg_(95-x)Ni_(x)(x=5,10,15)were smelted by the vacuum induction *** phase transformation and structural evolution of experimental alloys before and after reaction with hydrogen were char-acterized by X-ray diffraction,scanning electron microscopy and transmission electron *** cast specimens contain CeMg_(12),Mg and Mg_(2)Ni phases,and the increase in Ni content results in an obvious growth of Mg_(2)Ni *** isothermal and non-isothermal hydrogenation and dehydrogenation kinetics of the experimental specimens were investi-gated using the Sievert apparatus,differential scanning calorimetry and thermal gravimetric *** activation energy may be calculated using the Arrhenius and Kissinger *** experimental alloys have been shown to have good activation properties,with a reversible hydriding and dehydriding capacities of around 5.0 wt.%in the first *** initial dehydrogenation temperature of MgH_(2) decreases from 557.5 to 537.7 K with changing Ni content from 5 to 15 at.%.The dehydrogenation activation energy also reduces from 77.09 to 62.96 kJ/mol,which explains the improved hydrogen storage performance caused by Ni *** can be shown that the impact of Ni on the decomposition enthalpy of MgH_(2) is quite modest,with the absolute enthalpy(ΔHr)only decreasing from 78.48 to 76.15 kJ/mol.

关键词： Mg-based alloy Ni content Hydrogen storage kinetics Thermodynamic property Activation energy