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China Foundry 2025年

作者： Peng-cheng Zhou Guo-qiang You Jin-yu feng Lei wang Xiao Lin Bin Jiang College of Materials Science and Engineering Chongqing University National Engineering Research Center for Magnesium Alloys Chongqing University National Key Laboratory of Advanced Casting Technologies Chongqing University

Si-containing Mg alloys solidified at conventional rates often contain coarse and sharp Mg2Si phases,which can result in inferior material *** this study,Mg-6wt.%Si （Mg-6Si） alloy was prepared by wire arc additive manufacturing （WAAM）,employing the gas tungsten arc welding technique with rapid *** microstructures and mechanical properties of the WAAM alloy were investigated and compared with those of the as-cast samples produced using a metal *** results indicate that the WAAM Mg-6Si is harder and stronger than the as-cast *** microhardness of the WAAM Mg-6Si increases by 36.6%in comparison to that of as-cast Mg-6Si ***,the average tensile strengths at room temperature and 150°C increases by 63.4%and 21.3%,*** refines both the Mg2Si phase and the overall grains,resulting in a homogeneous morphology and improved mechanical *** granular Mg2Si phase,characterized by fine particles with a diffused distribution,shows a significant increase in *** acicular Mg2Si phase is distributed along the grain boundaries,and its concentration significantly *** average grain size of the Mg2Si phase is about 9.20μm,about 5 times *** refinement and distribution of the granular Mg2Si phase,as well as the reduction in the amount of needle-like Mg2Si particles,are the key factors for improving the mechanical properties of WAAM Mg-6Si alloy.

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Oxygen vacancies enriched Ir/WOx catalysts for the directly chem-catalytic conversion of cellulose to ethanol

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Tungsten 2025年第1期7卷 88-99页

作者： Yu-Jing Weng Zhao-Ying Ding Ying-Chao Li Yuan-feng Wu Yuan-Yang Xu Rui Chen Xiao-Lei Zhao Hai-Yong wang Da-Lei Zhang Yu-Long Zhang Henan Key Laboratory of Coal Green Conversion and International Joint Laboratory of Coal Clean Utilization College of Chemistry and Chemical Engineering Henan Polytechnic University Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Liaoning Institute of Energy Technology

Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications,including biological pathways and chemical *** chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods,offering a sustainable and carbon-neutral alternative to existing petrochemical and biological ***,Ir/WOxcatalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic *** catalyst achieved a high ethanol yield of 66.5%under optimal reaction conditions,approaching the theoretical yield limit of traditional ethanol *** results revealed the presence of oxygen defects,Bronsted/Lewis acidity,and Ir nanoclusters on the catalyst surface,working synergistically to facilitate the cascade catalysis of cellulose hydrolysis,sugar retro-aldol condensation reaction,and C2 intermediate hydrodeoxygenation to *** situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol *** manipulating subtle structural features,this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.

关键词： Cellulosic ethanol Chem-catalysis Hydrogenolysis Retro-aldol condensation Tungsten

Natural and human-induced decline and spatio-temporal differentiation of terrestrial water storage over the Lancang-Mekong River Basin

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Journal of Geographical Sciences 2025年第1期35卷 112-138页

作者： CHEN Junxu wang Yuan ZHAO Zhifang FAN Yunjiang LUO Xiaochuan YI Lu feng Siqi YANG Liang Emlyn Yunnan Key Laboratory of Soil Erosion Prevention and Green Development Yunnan University International Joint Research Center for Karstology Yunnan University School of Engineering Westlake University Department of Geography Ludwig Maximilian University of Munich (LMU)

Due to water conflicts and allocation in the Lancang-Mekong River Basin(LMRB), the spatio-temporal differentiation of total water resources and the natural-human influence need to be clarified. This work investigated LMRB's terrestrial water storage anomaly(TWSA) and its spatio-temporal dynamics during 2002–2020. Considering the effects of natural factors and human activities, the respective contributions of climate variability and human activities to terrestrial water storage change(TWSC) were separated. Results showed that:(1) LMRB's TWSA decreased by 0.3158 cm/a.(2) TWSA showed a gradual increase in distribution from southwest of MRB to middle LMRB and from northeast of LRB to middle LMRB. TWSA positively changed in Myanmar while slightly changed in Laos and China. It negatively changed in Vietnam, Thailand and Cambodia.(3) TWSA components decreased in a descending order of soil moisture, groundwater and precipitation.(4) Natural factors had a substantial and spatial differentiated influence on TWSA over the LMRB.(5) Climate variability contributed 79% of TWSC in the LMRB while human activities contributed 21% with an increasing impact after 2008. The TWSC of upstream basin countries was found to be controlled by climate variability while Vietnam and Cambodia's TWSC has been controlled by human activities since 2012.

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Catalytic atroposelective synthesis of indolyl quinazolinones bearing N-N/C-C diaxes

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Science China Chemistry 2025年

作者： Ning-Yi wang Shuo Gao Zhu-Di Shu Bei-Bei Cheng Chun Ma Yu-Chen Zhang feng Shi Research Center of Chiral Functional Heterocycles School of Chemistry and Materials Science Jiangsu Normal University School of Petrochemical Engineering Changzhou University School of Chemistry and Chemical Engineering Henan Normal University

The first catalytic atroposelective synthesis of indole derivatives bearing N-N/C-C diaxes has been established by the strategy of de novo ring formation. By this strategy, various indolyl quinazolinones bearing vicinal N-N/C-C diaxes were synthesized in high yields with overall good diastereoselectivities and excellent enantioselectivities via chiral phosphoric acid-catalyzed onepot asymmetric formal (5+1) cycloaddition/oxidation reaction. Moreover, such indolyl quinazolinones bearing vicinal N-N/CC diaxes have good configurational stability and could be converted into new chiral ligands with applications in asymmetric catalysis. Therefore, this work not only offered a new member for the family of diaxial atropisomers, but also provided a powerful strategy for catalytic asymmetric synthesis of atropisomers bearing N-N/C-C diaxes.

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Engineering N3C vacancies in hierarchical porous carbon nitride nanosheets for room temperature ultradeep photocatalytic aerobic oxidative desulfurization

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Science China Chemistry 2025年

作者： Yina Nie Weijie Yang Xin wang Xiang Li Lele Wei Xiaolin Bai Lin Liu feng Fu Jun Wan College of Chemistry & Chemical Engineering Research Institute of Comprehensive Energy Industrial Technology Shaanxi Key Laboratory of Chemical Reaction Engineering Yan'an University Anhui Engineering Research Center of Carbon Neutrality College of Chemistry and Materials Science Anhui Normal University

The production of ultra-low sulfur clean fuels holds global significance for improving energy efficiency and reducing environmental pollution. Photocatalytic aerobic oxidative desulfurization（PODS） offers an attractive approach to efficiently remove refractory heterocyclic aromatic sulfur compounds under mild conditions. However, the sluggish charge dynamics,insufficient molecule activation, and slow mass transfer within photocatalysts restrict the overall desulfurization efficiency,hindering the widespread application of this technology. Herein, we developed a defective g-C3N4（M1U3CN） photocatalyst with bridged N3Cvacancies and hierarchical porous structures to address these limitations. This catalyst not only demonstrates outstanding dibenzothiophene（DBT） removal efficiency of 99.6% for model oil with high conversion and selectivity but also achieves complete sulfur removal from gasoline as well as 96.7% sulfur removal for distilled diesel at room temperature,successfully achieving ultradeep aerobic oxidative desulfurization. The introduction of rich N3Cvacancies and abundant micromeso-macroporous distribution in M1U3CN enhances kinetic efficiencies by promoting charge carrier separation, mass transfer,and molecular activation simultaneously; resulting in exceptional PODS performance. This work provides a collaborative strategy to overcome kinetic challenges in aerobic oxidative desulfurization via defect and structural engineering of the catalyst.

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面向电子商务服务水平的变权分析评价方法

运筹与管理 2017年第6期26卷 163-166,184页

作者：余高锋李登峰王红雨三明学院信息工程学院福建三明365004 电子商务技术福建省高校工程研究中心福建三明365004 福州大学经济与管理学院福建福州350108

针对电子商务服务水平评价问题,提出一种基于变权分析方法的评价方法。首先,建立电子商务服务水平评价指标体系;其次,采用实数、区间数、三角模糊数、语言变量和直觉模糊数5种不同类型表示其评价信息,提出各个电子商务服务水平关于正理... 详细信息

针对电子商务服务水平评价问题,提出一种基于变权分析方法的评价方法。首先,建立电子商务服务水平评价指标体系;其次,采用实数、区间数、三角模糊数、语言变量和直觉模糊数5种不同类型表示其评价信息,提出各个电子商务服务水平关于正理想解的相对满意度计算方法,据此确定电子商务服务水平,并具体给出其变权分析评价步骤;最后,通过实例说明该方法的有效性和合理性。

关键词：异质信息变权分析法电子商务评价方法

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载银纳米纤维素/聚乙烯醇复合膜的制备及性能研究

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包装工程 2018年第9期39卷 51-55页

作者：魏占锋董峰王哲李雪青齐齐哈尔大学齐齐哈尔161006

目的制备一种具有良好力学性能和抑菌性能的新型抗菌聚乙烯醇复合膜。方法通过酸水解微晶纤维素制备纳米纤维素,经高碘酸钠氧化获得醛基纳米纤维素,加入银氨溶液原位合成载银纳米纤维素(Ag-DCNC)。以聚乙烯醇(PVA)为成膜基底,加入Ag-DCN... 详细信息

目的制备一种具有良好力学性能和抑菌性能的新型抗菌聚乙烯醇复合膜。方法通过酸水解微晶纤维素制备纳米纤维素,经高碘酸钠氧化获得醛基纳米纤维素,加入银氨溶液原位合成载银纳米纤维素(Ag-DCNC)。以聚乙烯醇(PVA)为成膜基底,加入Ag-DCNC共混流延制备载银纳米纤维素/聚乙烯醇复合膜。结果 Ag-DCNC体积分数为3%时,复合膜的拉伸强度比纯PVA膜提高了8.8%。Ag-DCNC体积分数为5%的复合膜对大肠杆菌和金黄色葡萄球菌均具有较好的抑菌效果。结论载银纳米纤维素/聚乙烯醇复合膜具有较好的力学强度,对2种细菌均有良好的杀菌效果。该材料不但具有良好的性能,而且合成工艺简单,可以作为一种很有前途的抑菌膜用于包装行业。

关键词：银纳米纤维素聚乙烯醇复合膜

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Evaluation of the therapeutic significance of Glehniae Radix polysaccharides on the ulcerative colitis through DSS-induced rat model

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Food Science and Human Wellness 2025年

作者： Jie Liu Xufang Geng Yuxin Yang Jiao Xu Haoran feng Tianshuo Zhang Guangzhao Zhou Man wang Changshun wang Dongsheng Jia Yuting Chen Bin Cong Ding Zhao The Postdoctoral Mobile Station of Basic Medicine， Hebei Medical University The Department of Pharmacognosy， School of Pharmacy， Hebei Medical University Hebei Key Laboratory of Forensic Medicine， College of Forensic Medicine， Hebei Medical University

Glehniae Radix has a wide range of pharmaceutical applications， and research on its main components has mainly focused on coumarins， alkaloids， lignans， and flavonoids， while neglecting the research on polysaccharides. Literature reports and our previous studies have shown that polysaccharides have certain therapeutic significance in immune regulation， antioxidant， anti-inflammatory and other aspects. Herein， the rat model of ulcerative colitis (UC) was established to evaluate the anti-inflammatory efficacy of the prepared Glehniae Radix polysaccharide (GLP) from the perspectives of inflammatory factors， intestinal tissue morphology， and microflora changes. The polysaccharides are mainly composed of galacturonic acid， rhamnose， glucose， galactose， and arabinose in molar ratios of 1.4:9.2:33.3:2.5:2.9， and GLP could downregulate the expression pro-inflammatory factors (interleukin-6， tumor necrosis factor-α， and interferon-γ) and significantly upregulate the expression of anti-inflammatory factor (interleukin-10). In addition， Glehniae Radix aqueous extract (GLA)， GLP with low dosage (GLPL) and GLP with high dosage (GLPH) could increase the number of goblet cells， enhance the integrity of crypt structure， and reverse the status of inflammatory infiltrating cells. Moreover， GLA and GLPH could upregulate Lactobacillus and Lachnoclostridium in UC rats， and appropriately downregulate Lachnospiraceae＿NK4A136＿group， thereby optimizing the proportion of bacterial flora and improving the intestinal microbial environment. Our findings not only be valuable as theoretical materials for the further clinical applications of GLP， but the identified biomarkers and metabolic pathways also provide new clues for the diagnosis of UC.

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Experimental study of negative capacitance in LEDs

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Optoelectronics Letters 2005年第2期 48-50页

作者： feng Lie-feng-(1), wang Jun-1, ZHU Chuan-yun-2, CONG Hong-xia-1, CHEN Yong-1, and wang Cun-da-1 1.Department of Applied Physics,Tianjin University,Tianjin 300072,China 2.Department of Photoelectronics & Physics,Foshan University,Foshan,Guangdong 528000,China

The experimental study on negative capacitance(NC) of various light-emitting diodes(LEDs) is *** result shows that all LEDs display the NC *** voltage modulated electroluminescence(VMEL) experiment confirms that the reason of negative capacitance is the strong recombination of the injected carriers in the active region of *** measures also verify that the dependence of NC on voltage and frequency in different LEDs is similar: NC phenomenon is more obvious with higher voltage or lower frequency.

关键词： Experimental study of negative capacitance in LEDs

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TDS集散型数据控制网络

微处理机 2004年第6期25卷 16-17,20页

作者：冯毅王峰东北微电子研究所沈阳110032

本文以TDS集散型网络系统为基础 ,结合实际应用。

关键词： TDS集散型数据控制网络网络系统网络通讯主从机状态切换

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