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Rare Metals 2024年第9期43卷 4367-4376页

作者： Wei Chen Ya-Hui Sun Tian Xu Xue-Bin yu Guang-Lin xia Department of Materials Science Fudan UniversityShanghai 200433China

2LiBH_(4)-MgH_(2)composite is one of the most attractive reactive hydride composites with a theoretic hydrogen capacity of 10.8 wt%.However,the large nucleation restriction of MgB_(2)during the second step of dehydrogenation results in sluggish hydrogen storage kinetics and high operating temperature,which hinders its practical application as on-board hydrogen storage ***,Al3Ti doped Al nanoparticles(AT NPs)are prepared by a facile chemical reduction reaction to improve the hydrogen storage performance of 2LiBH_(4)-MgH_(2)*** the initial H_(2)desorption process,MgAlB_(4)and TiB_(2)that have identical crystal structure and low d-value mismatch with MgB_(2)resulting from the reaction between AT NPs and 2LiBH_(4)-MgH_(2)composite serve as effective nucleation sites for the formation of MgB_(2).As a result,the apparent activation energy of the two-step H_(2)desorption of AT NPs doped 2LiBH_(4)-MgH_(2)composite are notably decreased to(110.0±5.9)and(119.6±1.4)kJ·mol^(-1),which is 55.5 and 33.5 kJ·mol^(-1)lower than that of the undoped *** importantly,a reversible hydrogen storage capacity of 9.2 wt%after 10cycles of H_(2)desorption and adsorption could be achieved,corresponding to a capacity retention rate of 99%.The building of reactive bimetallic catalyst towards in situ formation of heterogeneous nucleation sites provides a new strategy for improving the hydrogen storage performance of reactive hydride composites.

关键词： Reversible hydrogen storage Reactive hydride composites Catalytic effects Heterogeneous nucleation

Molecular engineering binuclear copper catalysts for selective CO_(2) reduction to C_(2) products

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Journal of Energy Chemistry 2024年第6期93卷 166-173,I0005页

作者： Qi Zhao Kai Lei Bao yu xia Rachel Crespo-Otero Devis Di Tommaso Department of Chemistry School of Physical and Chemical SciencesQueen Mary University of LondonLondonE14NSUK Key Laboratory of Material Chemistry for Energy Conversion and Storage(Ministry of Education) Hubei Key Laboratory of Material Chemistry and Service FailureState Key Laboratory of Materials Processing and Die&Mould TechnologySchool of Chemistry and Chemical EngineeringHuazhong University of Science and Technology(HUST)Wuhan 430074HubeiChina Department of Chemistry University College LondonLondonWC1H 0AJUK Digital Environment Research Institute Queen Mary University of LondonEmpire HouseLondon E11HHUK

Molecular copper catalysts serve as exemplary models for correlating the structure-reaction-mechanism relationship in the electrochemical CO_(2) reduction(eCO_(2)R),owing to their adaptable environments surrounding the copper metal *** investigation,employing density functional theory calculations,focuses on a novel family of binuclear Cu molecular *** modulation of their coordination configuration through the introduction of organic groups aims to assess their efficacy in converting CO_(2) to C_(2)*** findings highlight the crucial role of chemical valence state in shaping the characteristics of binuclear Cu catalysts,consequently influencing the eCO_(2)R behaviour,Notably,the Cu(Ⅱ)Cu(Ⅱ)macrocycle catalyst exhibits enhanced suppression of the hydrogen evolution reaction(HER),facilitating proton trans fer and the eCO_(2)R *** rthermore,we explo re the impact of diverse electro n-withdrawing and electron-donating groups coordinated to the macrocycle(R=-F,-H,and-OCH_3)on the electron distribution in the molecular *** placement of-OCH_3 groups in the macrocycles leads to a favourable oxidation state of the Cu centres and subsequent C-C coupling to form C_(2) *** research provides fundamental insights into the design and optimization of binuclear Cu molecular catalysts for the electrochemical conversion of CO_(2) to value-added C_(2) products.

关键词： Molecular catalyst design Selective CO_(2)reduction C_(2)products Density functional theory calculations

Urinary metabolic profiles during Helicobacter pylori eradication in chronic gastritis

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World Journal of Clinical Cases 2024年第5期12卷 951-965页

作者： Wen-Ting An yu-xia Hao Hong-xia Li Xing-Kang Wu Department of Pharmacy Shanxi Provincial People’s HospitalTaiyuan 030012Shanxi ProvinceChina Department of Gastroenterology Shanxi Provincial People's HospitalTaiyuan 030012Shanxi ProvinceChina Department of Oncology Shanxi Provincial People’s HospitalTaiyuan 030012Shanxi ProvinceChina Modern Research Center for Traditional Chinese Medicine Shanxi UniversityTaiyuan 030006Shanxi ProvinceChina

BACKGROUND Helicobacter pylori(***)infection is a major risk factor for chronic gastritis,affecting approximately half of the global *** eradication is a popular treatment method for ***-positive chronic gastritis,but its mecha-nism remains *** metabolomics has been used to elucidate the mechanisms of gastric disease ***,no clinical study has been conducted on urinary metabolomics of chronic *** To elucidate the urinary metabolic profiles during *** eradication in patients with chronic *** We applied LC–MS-based metabolomics and network pharmacology to in-vestigate the relationships between urinary metabolites and ***-positive chronic gastritis via a clinical follow-up *** Our study revealed the different urinary metabolic profiles of ***-positive chronic gastritis before and after *** *** metabolites regulated by *** eradication therapy include cis-aconitic acid,isocitric acid,citric acid,L-tyrosine,L-phenylalanine,L-tryptophan,and hippuric acid,which were involved in four metabolic pathways:(1)Phenylalanine metabolism;(2)phenylalanine,tyrosine,and tryptophan biosynthesis;(3)citrate cycle;and(4)glyoxylate and dicarboxylate *** metabolomics and network pharmacology revealed that MPO,COMT,TPO,TH,EPX,CMA1,DDC,TPH1,and LPO were the key proteins involved in the biological progress of *** eradication in chronic *** Our research provides a new perspective for exploring the significance of urinary metabolites in evaluating the treatment and prognosis of ***-positive chronic gastritis patients.

关键词： LC-MS metabolomics chronic gastritis Helicobacter pylori urinary metabolites

Lactonization of dyes promoted by a coordination cage facilitates cavity-induced chromism as ion mobile detector

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Science China Chemistry 2024年第5期67卷 1554-1560页

作者： Liangliang Zhang yu Liang Zhifeng xiao yuxuan Meng Jinyi Huang Xi Lin Ji Li Hong-cai Zhou yu Fang Strait Institute of Flexible Electronics(SIFE Future Technologies)Fujian Normal University and Strait Laboratory of Flexible Electronics(SLoFE)Fuzhou 350017China State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Department of Chemistry Texas A&M UniversityCollege StationTexas 77842-3012USA State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Frontiers Science Center for Flexible Electronics(FSCFE) MIIT Key Laboratory of Flexible Electronics(KLoFE)Northwestern Polytechnical UniversityXi’an 710072China

Dye molecules often change colors(so-called “chromism”) according to the environment variation. However, they are rarely induced by a catalytic amount of cavity. Through encapsulation in the cavity of a porous coordination cage(PCC-2), Rhodamine B(1) is transformed from red quinonoid form(1q) into colorless lactone form(1l) in aprotic polar solutions. The μ4-OH groups in the cavity of PCC-2 are shown to stabilize the uncommon zwitterion intermediate(1z), followed by converting to 1l, thus accelerating the equilibrium. The chromism is catalyzed by 0.25 mol% of PCC-2, and the reaction rate is improved by 80,400times. 1@PCC-2 can be further fabricated to a sol-gel that exhibits ion recognition properties. The resulting encapsulation and stabilization of an unconventional intermediate by a catalytic amount of the coordination cage provides fundamental insights into molecular isomerization and has potential use in chemical sensing.

关键词： porous coordination cage Zwitterion intermediate cavity Rhodamine B chromism

补骨脂水煎剂对去卵巢骨质疏松大鼠骨代谢的影响

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中国组织工程研究与临床康复 2009年第2期13卷 268-271页

作者：蔡玉霞张剑宇山西医科大学山西省太原市030001

背景:采用雌激素替代疗法可以缓解绝经后妇女骨质疏松症状,但长期应用会出现明显的毒副作用;具有雌激素活性的补骨脂在治疗骨质疏松症方面有明显效果,且可避免使用雌激素带来的副作用。目的:观察补骨脂水煎剂对去卵巢骨质疏松大鼠骨代... 详细信息

背景:采用雌激素替代疗法可以缓解绝经后妇女骨质疏松症状,但长期应用会出现明显的毒副作用;具有雌激素活性的补骨脂在治疗骨质疏松症方面有明显效果,且可避免使用雌激素带来的副作用。目的:观察补骨脂水煎剂对去卵巢骨质疏松大鼠骨代谢和血清细胞因子的影响。设计、时间及地点:随机对照,动物体内实验,于2008-04/07在山西医科大学生理学实验动物中心实验室完成。材料:100mL含100g生药的100%浓度的补骨脂水煎剂由山西省第二人民医院中药房鉴定制备。肿瘤坏死因子α试剂盒为北京晶美生物工程有限公司产品,骨钙素、1,25-二羟基维生素D3、雌二醇试剂盒为上海卓康生物科技有限公司产品。QDR型4500A双能X射线骨密度仪为美国HOLOGIC公司产品。方法:选用健康雌性鼠龄4个月的Wistar大鼠22只,随机将22只大鼠分为假手术组7只、模型组7只,补骨脂组8只,后2组采用切除双侧卵巢的方法制备骨质疏松模型,假手术组不切除卵巢。补骨脂组在造模后灌胃补骨脂水煎剂每天早晚各3mL,其余组灌胃等量生理盐水,共12周。主要观察指标:给药结束后,分别按试剂盒操作说明测定血清雌二醇,骨钙素,1,25-二羟基维生素D3,肿瘤坏死因子α水平。利用QDR4500A型DEXA骨密度仪测量大鼠股骨密度。结果:与假手术组比较,模型组大鼠血清雌二醇、1,25-二羟基维生素D3水平和骨密度显著降低(P<0.01),血清肿瘤坏死因子α水平、骨钙素水平升高(P<0.05)。与模型组比较,补骨脂组大鼠血清雌二醇仍处于较低水平,骨密度、血清1,25-二羟基维生素D3、骨钙素水平明显升高(P<0.05～0.01),血清肿瘤坏死因子α水平显著降低(P<0.01)。结论:补骨脂水煎剂可改善去卵巢骨质疏松大鼠骨代谢指标和血清细胞因子水平。

关键词：补骨脂骨质疏松雌激素肿瘤坏死因子α 骨钙素

Unveiling the geometric site dependent activity of spinel Co_(3)O_(4)for electrocatalytic chlorine evolution reaction

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Journal of Energy Chemistry 2024年第5期92卷 95-103页

作者： Linke cai Yao Liu Jingfang Zhang Qiqi Jia Jiacheng Guan Hongwei Sun yu yu Yi Huang Key Laboratory of Pesticide&Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhan 430079HubeiChina Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of EducationHubei Key Laboratory of Novel Reactor and Green Chemical TechnologySchool of Chemical Engineering&PharmacyWuhan Institute of TechnologyWuhan 430205HubeiChina College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108FujianChina School of Chemistry and Chemical Engineering Anhui UniversityHefei 230601AnhuiChina

Spinel cobalt oxide(Co_(3)O_(4)),consisting of tetrahedral Co^(2+)(CoTd)and octahedral Co^(3+)(CoOh),is considered as promising earth-abundant electrocatalyst for chlorine evolution reaction(CER).Identifying the catalytic contribution of geometric Co site in the electrocatalytic CER plays a pivotal role to precisely modulate electronic configuration of active Co sites to boost ***,combining density functional theory calculations and experiment results assisted with operando analysis,we found that the Co_(Oh) site acts as the main active site for CER in spinel Co_(3)O_(4),which shows better Cl^(-)adsorption and more moderate intermediate adsorption toward CER than CoTd site,and does not undergo redox transition under CER condition at applied *** by above findings,the oxygen vacancies were further introduced into the Co_(3)O_(4) to precisely manipulate the electronic configuration of Co_(Oh) to boost Cl^(-)adsorption and optimize the reaction path of CER and thus to enhance the intrinsic CER activity *** work figures out the importance of geometric configuration dependent CER activity,shedding light on the rational design of advanced electrocatalysts from geometric configuration optimization at the atomic level.

关键词： Chlorine evolution reaction Geometry effects Active chlorine Electronic configuration optimization Spinel oxides

Illuminating spin-crossover octanuclear metal-organic cages

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Science China Chemistry 2024年第4期67卷 1208-1215页

作者： Zhi-Kun Liu Alyona A.Starikova yu-xia Li Ke Sun Meng yu Zi-Shuo Yao Jun Tao Key Laboratory of Cluster Science of Ministry of Education School of Chemistry and Chemical EngineeringLiangxiang CampusBeijing Institute of TechnologyBeijing 102488China Institute of Physical and Organic Chemistry Southern Federal UniversityRostov-on-Don 344090Russia

Spin-crossover(SCO)materials that reversibly switch between high-and low-spin states have potential for the storage of spin state-relative information,and have gained much attention incorporating secondary physical properties,such as fluorescence and magneto-optical *** this study,we synthesized three octanuclear metal-organic cages(MOCs)using tetraphenylethylene-based luminophores,aldehydes,and Fe^(Ⅱ)salts,by subcomponent self-assembly approach,namely[Fe1]-[Fe3].By controlling the ligand-field strength and guest encapsulation,we finely tuned their SCO *** them,MOC[Fe2]displayed nearly complete SCO behavior in the solid state,which is rare for high-nuclearity *** also demonstrated the coupling of SCO with fluorescence emission in these MOCs by using isostructural Zn^(Ⅱ)complexes([Zn1]-[Zn3])as control experiments,for the first *** calculations revealed the energy-transfer mechanism between fluorophores and SCOactive centers,which emphasizes the significant contribution of d-d transitions in the interplay between the occurrence of SCO and fluorescence emission.

关键词： metal-organic cages spin crossover fluorescence switching materials DFT calculation

Water modeling on fluid flow and mixing phenomena in a BOF steelmaking converter

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Journal of Iron and Steel Research International 2024年第3期31卷 595-607页

作者： Xin-yu cai Hao-jian Duan Ding-han Li Anjun Xu Li-feng Zhang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing 100083China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

A 1∶8 physical water model was constructed to investigate the fluid flow and mixing phenomena in the basic oxygen furnace(BOF)*** particle image velocimetry was employed to measure the velocity distribution of the bath and the high-speed camera was applied to capture the cavity shape in the combined blowing BOF *** mixing time for varied operating conditions was measured by the stimulus-response *** cavity depth increased with the decrease in the lance height and the increase in the top gas flow rate while the bottom blowing gas had little influence on the cavity *** minimum cavity depth was obtained under the condition of a 69.8 m^(3)/h top gas flow rate,a 287.5 mm lance height and a 0.93 m^(3)/h bottom blowing gas flow rate,which was 161.2 *** mixing time decreased as the lance height decreased and the top blowing gas flow rate *** mixing time was first decreased and then increased with the increase in the bottom gas flow *** the condition of 69.8 m^(3)/h gas flow rate of top blowing,the 287.5 mm lance height and the 0.93 m^(3)/h gas flow rate of bottom blowing,the mixing time in the converter was 48.65 *** empirical formula between the stirring power and the mixing time in the converter was calculated.

关键词： Water model Fluid flow Particle image velocimetry Mixing time BOF converter

The environmental analysis and site selection of mussel and large yellow croaker aquaculture areas based on high resolution remote sensing

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Acta Oceanologica Sinica 2024年第3期43卷 66-86页

作者： Lina cai Jie Yin xiaojun Yan Yongdong Zhou Rong Tang Menghan yu Marine Science and Technology College Zhejiang Ocean UniversityZhoushan 316022China Zhejiang Marine Fisheries Research Institute Zhejiang Ocean UniversityZhoushan 316004China

Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was proposed and applied to determine the basic environmental characteristics of the best mussel and large yellow croaker aquaculture *** methodology includes the first step of extraction of the location distribution and the second step of the extraction of internal environmental *** fishery ranching index(FRI1,FRI2)was established to extract the mussel and the large yellow croaker aquaculture area in Zhoushan,using Gaofen-1(GF-1)and Gaofen-6(GF-6)satellite data with a special resolution of 2 *** the second step,the environmental factors such as sea surface temperature(SST),chlorophyll a(Chl-a)concentration,current and tide,suspended sediment concentration(SSC)in mussel aquaculture area and large yellow croaker aquaculture area were extracted and analyzed in *** results show the following three points.(1)For the extraction of the mussel aquaculture area,FRI1 and FRI2 are complementary,and the combination of FRI1 and FRI2 is suitable to extract the mussel aquaculture *** for the large yellow croaker aquaculture area extraction,FRI2 is suitable.(2)Mussel aquaculture and the large yellow croaker aquaculture area in Zhoushan are mainly located on the side near the islands that are away from the eastern open *** water environment factor template suitable for mussel and large yellow croaker aquaculture was determined.(3)This two-step remote sensing method can be used for the preliminary screening of potential site selection for the mussels and large yellow croaker aquaculture area in the *** fishery ranching index(FRI1,FRI2)in this paper can be applied to extract the mussel and large yellow croaker aquaculture areas in coastal waters around the world.

关键词： mussel aquaculture area large yellow croaker aquaculture area high resolution satellite site selection environmental analysis

Histological,transcriptomic,and gene functional analyses reveal the regulatory events underlying gibberellin-induced parthenocarpy in tomato

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Horticultural Plant Journal 2024年第1期10卷 156-170页

作者： Shaobo Niu yu He Siwei Yan Zhengliang Sun Run cai Yan Zhang Shaanxi Engineering Research Center for Vegetables College of HorticultureNorthwest A&F UniversityYanglingShaanxi 712100China

Gibberellin(GA)is one of the major plant hormones that promote parthenocarpy,a highly valuable agronomic ***,we demonstrated that exogenous GA3application triggered the formation of parthenocarpic fruits with smaller size but unchanged shape in tomato(Solanum lycopersicum).These fruits exhibited a thicker pericarp,undeveloped ovules,and few jelly tissues,leading to smaller locules with empty *** investigation showed that GA treatment produced more cell layers with larger cells in the pericarp,suggesting its promotion in both cell division and *** analyses between GA-3and mock-treated unpollinated ovaries/fruits identified a large number of differentially expressed genes related to hormones,cell division,cell expansion,and transcription factors,implying that they coordinately regulated parthenocarpy conferred by *** particular,the downregulation of five reported repressors of tomato parthenocarpy,including two auxin signaling components,AUXIN RESPONSE FACTOR5(SlARF5)and Sl ARF7,and three MADS-box genes,TOMATO APETALA3(TAP3),TOMATO PISTILLATA(TPI),and AGAMOUS-LIKE6(SlAGL6),after GA treatment might play a key role in this ***,we found that the knockdown of a GA signaling factor SlMYB33,which was depressed by GA treatment,induced parthenocarpic fruit set in tomato,an effect that might have been achieved by enhancing GA biosynthesis and decreasing the expression of some repressors of tomato ***,our results provide a basis for understanding the regulatory mechanism of GA in tomato parthenocarpy.

关键词： Tomato Gibberellin Parthenocarpy Histology Transcriptome SlMYB33