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Exploring catalyst developments in heterogeneous CO2 hydrogenation to methanol and ethanol:A journey through reaction pathways

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Journal of Energy Chemistry 2025年第2期101卷 345-384页

作者： Rasoul Salami Yimin Zeng Xue han Sohrab Rohani ying Zheng Department of Chemical and Biochemical Engineering Western University Canmet MATERIALS Natural Resources Canada

The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased *** the proposed methods,the hydrogenation of CO2to produce marketable carbon-based products like methanol and ethanol is a practical approach that offers great potential to reduce *** significant volumes of methanol are currently produced from CO2,developing highly efficient and stable catalysts is crucial for further enhancing conversion and selectivity,thereby reducing process *** in-depth examination of the differences and similarities in the reaction pathways for methanol and ethanol production highlights the key factors that drive C-C *** these factors guides us toward developing more effective catalysts for ethanol *** this paper,we explore how different catalysts,through the production of various intermediates,can initiate the synthesis of methanol or *** catalytic mechanisms proposed by spectroscopic techniques and theoretical calculations,including operando X-ray methods,FTIR analysis,and DFT calculations,are summarized and *** following discussion explores the structural properties and composition of catalysts that influence C-C coupling and optimize the conversion rate of CO2into ***,the review examines recent catalysts employed for selective methanol and ethanol production,focusing on single-atom catalysts.

关键词： CO 2 hydrogenation Methanol Ethanol Catalytic mechanism Operando techniques Single atom catalyst Tandem catalyst

魟鱼软骨多糖对Lewis肺癌MMP-9表达的影响

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中国中药杂志 2006年第4期31卷 325-328页

作者：郭斌韩冠英李智中国医科大学基础医学院辽宁沈阳110001 锦州医学院辽宁锦州121001

目的:鱼软骨多糖(RCG)对Lewis肺癌基质金属蛋白酶9(MMP-9)表达的影响。方法:建立小鼠Lewis肺癌模型,将动物分为生理盐水组、不同剂量鱼软骨多糖组、环磷酰胺组,观察肿瘤生长情况,绘制肿瘤生长曲线,计算原发瘤抑制率;采用RT-PCR和Western... 详细信息

目的:鱼软骨多糖(RCG)对Lewis肺癌基质金属蛋白酶9(MMP-9)表达的影响。方法:建立小鼠Lewis肺癌模型,将动物分为生理盐水组、不同剂量鱼软骨多糖组、环磷酰胺组,观察肿瘤生长情况,绘制肿瘤生长曲线,计算原发瘤抑制率;采用RT-PCR和Western blot检测瘤组织MMP-9基因和蛋白表达。结果:该多糖各剂量组小鼠的肿瘤生长曲线平缓,小鼠原发瘤抑制率、肺转移数与生理盐水组比较差异有显著性(P<0.05;P<0.01);与生理盐水比较,鱼软骨多糖各剂量组,MMP-9 mRNA和蛋白表达水平显著降低(P<0.01)。结论:鱼软骨多糖明显抑制小鼠Lewis肺癌原发瘤的生长和转移,可能与其抑制肿瘤MMP-9基因和蛋白表达有关。

关键词：魟鱼软骨多糖 Lewis肺癌基质金属蛋白酶9

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魟鱼软骨多糖的分离纯化及生物活性的研究

中草药 2006年第8期37卷 1210-1214页

作者：郭斌韩冠英李智中国医科大学基础医学院天然药物研究室辽宁沈阳110001 锦州医学院辽宁锦州121001

目的研究魟鱼软骨多糖(raycartila geglycosam inoglycans,RCG)的提取、分离与纯化方法,并初步探讨其生物活性。方法采用盐酸胍提取、丙酮分级沉淀、膜超滤、Sephadex凝胶柱色谱分离、纯化获得魟鱼软骨多糖,由HPLC确定其相对分子质量和... 详细信息

目的研究魟鱼软骨多糖(raycartila geglycosam inoglycans,RCG)的提取、分离与纯化方法,并初步探讨其生物活性。方法采用盐酸胍提取、丙酮分级沉淀、膜超滤、Sephadex凝胶柱色谱分离、纯化获得魟鱼软骨多糖,由HPLC确定其相对分子质量和质量分数;建立Lewis肺癌小鼠模型,将实验分为生理盐水(Saline)组、不同剂量(500、250、125mg/kg)鱼软骨多糖组、环磷酰胺(CTX,60mg/kg)组,观察小鼠肿瘤生长情况,绘制肿瘤生长曲线,计算原发瘤与肺转移灶数抑瘤率,免疫组织化学染色计数肿瘤组织微血管密度(MVD),采用RT-PCR检测瘤组织血管内皮生长因子(VEGF)基因表达。结果经HPLC检测,该组分为单一多糖,其质量分数达99%以上。生物活性检测结果表明,与生理盐水组比较,该多糖各剂量组小鼠的肿瘤生长曲线平缓,原发瘤抑瘤率、肺转移灶数与生理盐水组比较差异显著(P<0.05、0.01);与生理盐水组比较,鱼软骨多糖各剂量组MVD显著减少、VEGFmRNA表达水平显著降低(P<0.01)。结论鱼软骨多糖明显抑制小鼠Lewis肺癌原发瘤的生长和转移,并可抑制肿瘤的血管形成。

关键词：魟鱼软骨多糖 Lewis肺癌微血管密度(MVD) 血管内皮生长因子(VEGF)

Effect of lanthanum on microstructure of a nickel-based single crystal superalloy

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China Foundry 2025年第1期22卷 55-64页

作者： Hong Gao Kai guan Ren-jie Cui Jian-chao Qin Zi-han Zhao Zhao-hui Huang Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical MaterialsBeijing 100095China

To enhance the high-temperature oxidation resistance and mechanical properties of a secondgeneration nickel-based superalloy,various concentrations of lanthanum(La)ranging from 5.0×10^(-5)wt.%to 3.4×10^(-4)wt.%are added to the *** microstructure of the nickel-based single crystal superalloy with trace of La was examined by means of SEM,EDS and *** show the addition of La decreases the segregation of elements and increases the amount ofγ/γ′eutectics of the as-cast alloy,and in the interdendritic region,the growth of eutectics is accompanied by the growth of strip clusters composed of Ni_(5)La and Ni_(3)*** the La content in the alloy increases,the proportion of Ni_(5)La in the cluster *** heat treatment,incipient melting occurs in the cluster regions,leading to an increase in microporosity compared to the original as-cast ***,the heat treatment alters the shape of the clusters from a strip morphology to an elliptical one,and it changes their composition from Ni_(5)La and Ni_(3)Ta to a combination of Ni_(5)La,Ni_(3)Ta,and MC carbides.

关键词： single crystal superalloy lanthanum microstructure heat-treatment precipitate phase

Synthesis ofδ-MnO_(2)via ozonation routine for low temperature formaldehyde removal

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Journal of Environmental Sciences 2025年第1期147卷 642-651页

作者： Guijun Fan Yacong Guo Shaohua Chai Le Zhang Jian guan Guojun Ma Ning han Yunfa Chen State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China College of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Science and Technology on Particle Materials Institute of Process EngineeringChinese Academy of SciencesBeijing 361021China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Petrochemical Engineering&Environment Zhejiang Ocean UniversityZhoushan 316022China

Nowadays,it is still a challenge to prepared high efficiency and low cost formaldehyde(HCHO)removal catalysts in order to tackle the long-living indoor air ***,δ-MnO_(2)is successfully synthesized by a facile ozonation strategy,where Mn^(2+)is oxidized by ozone(O_(3))bubble in an alkaline *** presents one of the best catalytic properties with a low 100%conversion temperature of 85℃for 50 ppm of HCHO under a GHSV of 48,000 mL/(g·hr).As a comparison,more than 6 times far longer oxidation time is needed if O3 is replaced by O_(2).Characterizations show that ozonation process generates a different intermediate of tetragonalβ-HMnO_(2),which would favor the quick transformation into the final productδ-MnO_(2),as compared with the relatively more thermodynamically stable monoclinicγ-HMnO_(2)in the O_(2)***,HCHO is found to be decomposed into CO_(2)via formate,dioxymethylene and carbonate species as identified by room temperature insitu diffuse reflectance infrared fourier transform *** these results show great potency of this facile ozonation routine for the highly activeδ-MnO_(2)synthesis in order to remove the HCHO contamination.

关键词： δ-MnO_(2) Ozone oxidation HCHO oxidation In-situ DRIFTS

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魟鱼软骨多糖抗血管形成的实验研究

中国药房 2008年第1期19卷 20-22页

作者：郭斌韩冠英辽宁医学院锦州市121000

目的:探讨魟鱼软骨多糖(RCG)对血管形成的作用。方法:原代培养人脐静脉内皮细胞,采用MTT法检测不同浓度RCG对人脐静脉内皮细胞增殖的影响;缝线诱导大鼠角膜新生血管,通过计算新生血管面积评价不同浓度RCG对大鼠角膜新生血管的作用;建立... 详细信息

目的:探讨魟鱼软骨多糖(RCG)对血管形成的作用。方法:原代培养人脐静脉内皮细胞,采用MTT法检测不同浓度RCG对人脐静脉内皮细胞增殖的影响;缝线诱导大鼠角膜新生血管,通过计算新生血管面积评价不同浓度RCG对大鼠角膜新生血管的作用;建立小鼠Lewis肺癌模型,观察不同浓度RCG作用后肿瘤生长情况,计算原发瘤抑制率,免疫组织化学染色计数肿瘤组织微血管密度(MVD)。结果:RCG可明显抑制人脐静脉内皮细胞的体外增殖,IC50为***-1;与生理盐水组比较,应用不同浓度RCG后新生血管面积明显减少(P<0.01),原发瘤抑制率呈浓度依赖性,MVD值降低(P<0.01)。结论:RCG对实验动物具有良好的抗血管生成活性。

关键词：魟鱼软骨多糖人脐静脉内皮细胞大鼠小鼠角膜新生血管微血管密度

Exposure of individuals aged 18-44 years to personal care products in Beijing,China:Exposure profiles,possible influencing factors,and risk assessment

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Journal of Environmental Sciences 2025年第2期148卷 691-701页

作者： Xu Zhang Linxue han Qi Sun Xiaochen Wang Xiaojian Hu Xiao Lin ying Zhu China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijing 100021China The Bureau for Health Inspection and Supervision of Haidian District Beijing 100037China

Personal care products(PCPs)are a class of emerging pollutants that have attracted public concern owing to their harmful effects on humans and the *** data is valuable for insight the levels of PCPs in the human body and can be crucial for identifying potential health *** gain a better understanding of timely exposure profiles and health risk of reproductive-age population to PCPs,we determined six parabens,six benzophenone-type ultraviolet filters,and three disinfectants in 256 urine samples collected from young adults aged 18-44 years in Beijing,*** urinary levels of benzophenone-3(BP-3)and 4-hydroxybenzophenone(4-OHBP)were significantly higher in summer compared to winter,suggesting these compounds have different seasonal usage ***,the total concentration of 15 PCPs in female was 430 ng/mL,approximately two times higher than that in male.P-chloro-m-xylenol(PCMX),as a new type of antibacterial agent,has the greatest level among all target analytes,indicating the increasingly use of this antibacterial alternative *** potential influencing factors that lead to the elevated exposure level of PCPs were *** 19%of the target population had a high hazard index value(greater than 1)which was attributed to exposure to propyl paraben(PrP),benzophenone-1(BP-1),BP-3 and PCMX,indicating that PCPs may pose a relatively high exposure risk at environmental levels that should be a cause for concern.

关键词： Personal care products Hazard quotient Risk assessment Exposure patterns Urine

Bistable switch molecule DPACdCl_(4) showing four physical channels and high phase transition temperature

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Chinese Chemical Letters 2025年第1期36卷 591-596页

作者： ying-Yu Zhang Jia-Qi Luo Yan han Wan-ying Zhang Yi Zhang Hai-Feng Lu Da-Wei Fu Institute for Science and Applications of Molecular Ferroelectrics Key Laboratory of the Ministry of Education for Advanced Catalysis MaterialsZhejiang Normal UniversityJinhua 321004China Ordered Matter Science Research Center Jiangsu Key Laboratory for Science and applications of Molecular FerroelectricsSoutheast UniversityNanjing 211189China

Multiple switchable physical channels within one material or device,encompassing optical,electrical,thermal,and mechanical pathways,can enable multifunctionality in mechanical-thermal-opto-electronic *** integrated encryption and enhanced performance in storage and sensing presents a formidable challenge in the synthesis and functionality of new *** an effort to overcome the complexities associated with these multiple physical functions,this study investigates the large-size crystal of DPACdCl_(4)(DPA=diisopropylammonium),revealing significant features in rare multi-channel *** compound demonstrates the ability to switch between"OFF/0"and"ON/1"states in the mechanical-thermal-opto-electronic ***,DPACd Cl_(4)possesses four switchable physical channels,characterized by a higher phase transition temperature of 440.7 K and a competitive piezo-electric coefficient of 46 pC/***,solid-state NMR analysis indicates that thermally activated molecular vibrations significantly contribute to its multifunctional switching capabilities.

关键词： Organic-inorganic hybrid Phase transition Crystal Perovskite Piezoelectricity

Attar: RRAM-based in-memory attention accelerator with software-hardware co-optimization

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Science China(Information Sciences) 2025年第3期68卷 371-387页

作者： Bing LI ying QI ying WANG Yinhe han Information Engineering College Capital Normal University Research Center for Intelligent Computing Systems Institute of Computing TechnologyChinese Academy of Sciences

The attention mechanism has become a pivotal component in artificial intelligence, significantly enhancing the performance of deep learning applications. However, its quadratic computational complexity and intricate computations lead to substantial inefficiencies when processing long sequences. To address these challenges, we introduce Attar, a resistive random access memory(RRAM)-based in-memory accelerator designed to optimize attention mechanisms through software-hardware co-optimization. Attar leverages efficient Top-k pruning and quantization strategies to exploit the sparsity and redundancy of attention matrices, and incorporates an RRAM-based in-memory softmax engine by harnessing the versatility of the RRAM crossbar. Comprehensive evaluations demonstrate that Attar achieves a performance improvement of up to 4.88× and energy saving of 55.38% over previous computing-in-memory(CIM)-based accelerators across various models and datasets while maintaining comparable accuracy. This work underscores the potential of in-memory computing to enhance the efficiency of attention-based models without compromising their effectiveness.

关键词： RRAM computing-in-memory attention pruning quantization

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