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Revision of the Conodont Mockina slovakensis and Its Paleogeographic Implications for the Upper Triassic Intraplatform Basins of the Alps

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Journal of Earth Science 2021年第3期32卷 657-666页

作者： Yixing Du viktor Karadi Guido Roghi Maurizio Ponton Andrea Cozzi Manuel Rigo department of Geosciences University of Padova35131 PadovaItaly department of Palaeontology Eotvos Lorand UniversityBudapest 1117Hungary Institute of Geosciences and Earth Resources National Research Council of Italy35131 PadovaItaly department of Mathematics and Geosciences University of Trieste34128 TriesteItaly Eni Sharjah B.v 73500 SharjahUnited Arab Emirates

Mockina slovakensis,thought to have evolved from Epigondolella praeslovakensis,is an important species of the Norian(Upper Triassic),generally considered as the representative of the uppermost Alaunian to upper Sevatian in the *** previous description of *** was incomplete,thus has led to some *** thus update the description of *** and discuss its comparisons and occurrence based on the new conodont investigations in Dolomia di Forni and the data from previous *** conodont assemblage in the succession of Dolomia di Forni is dominated by ***,along with rare *** and *** described two morphotypes of ***(morphotypes A and B),on the basis of shape of the lateral *** two morphotypes can also be observed in the ***,*** is usually documented as almost monospecific conodont association in intraplatform basins,thus its paleogeographic implications are also discussed.

关键词： Mockina conodont morphotype intraplatform basin

Corrosion Resistance ofAA6063-Type AI-Mg-Si Alloy by Silicon Carbide in Sodium Chloride Solution for Marine Application

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Journal of Marine Science and Application 2015年第4期14卷 459-462页

作者： Ojo Sunday Isaac Fayomi Malik Abdulwahab Abimbola Patricia ldowu Popoola Ferdinand Asuke department of Chemical Metallurgical and Materials Engineering Tshwane University of Technology X680 Pretoria South Africa department of Mechanical engineering Covenant University P.M.B 1023 Ota Ogun State Nigeria department of Metallurgical and Materials engineering Ahmadu Bello University P. M.B 1045 Zaria Nigeria

The present work focused on corrosion inhibition of AA6063 type Al-Mg-Si alloy in sodium chloride （NaCI） solution with a silicon carbide inhibitor, using the potentiodynamic electrochemical method. The aluminium alloy surface morphology was examined, in the as-received and as-corroded in the un-inhibited state, with scanning electron microscopy equipped with energy dispersive spectroscopy （SEM-EDS）. The results obtained via linear polarization indicated a high corrosion potential for the unprotected as-received alloy. Equally, inhibition efficiency as high as 98.82% at 10.0 g/v silicon carbide addition was obtained with increased polarization resistance fRy）, while the current density reduced significantly for inhibited samples compared to the un-inhibited aluminium alloy. The adsorption mechanism of the inhibitor aluminium alloy follows the Langmuir adsorption isotherm. This shows that the corrosion rate of aluminium alloy with silicon carbide in NaCI environment decreased significantly with addition of the inhibitor.

关键词： corrosion resistance silicon carbide sodium chloride (NaCI) aluminium alloy interface inhibition efficiency thin film adsorption isotherm potentiodynamic electrochemical method marine application

An enhanced chemopreventive effect of methyl donor S-adenosylmethionine in combination with 25-hydroxyvitamin D in blocking mammary tumor growth and metastasis

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Bone Research 2020年第3期8卷 300-311页

作者： Niaz Mahmood Ani Arakelian William J.Muller Moshe Szyf Shafaat A.Rabbani department of Medicine McGill University Health CentreMontrealQC H4A3J1Canada department of Biochemistry McGill UniversityMontrealQC H3A 1A3Canada department of Pharmacology and Therapeutics McGill UniversityMontrealQC H3G 1V6Canada

Therapeutic targeting of metastatic breast cancer still remains a challenge as the tumor cells are highly heterogenous and exploit multiple pathways for their growth and metastatic spread that cannot always be targeted by a single-agent monotherapy ***,a rational approach through simultaneous targeting of several pathways may provide a better anti-cancer therapeutic effect We tested this hypothesis using a combination of two nutraceutical agents S-adenosylmethionine(SAM)and vitamin D(vit.D)prohormone[25-hydroxyvitamin D;/25(OH)D,]that are individually known to exert distinct changes in the expression of genes involved in tumor growth and *** results show that both SAM and 25(OH)D monotherapy significantly reduced proliferation and clonogenic survival of a panel of breast cancer cell lines in vitro and inhibited tumor growth,lung metastasis,and breast tumor cell colonization to the skeleton in ***,these effects were significantly more pronounced in the combination ***-Sequencing revealed that the transcriptomic footprint on key cancer-related signaling pathways is broader in the combination setting than any of the ***,comparison of the differentially expressed genes from our transcriptome analyses with publicly available cancer-related dataset demonstrated that the combination treatment upregulates genes from immune-related pathways that are otherwise downregulated in bone metastasis in *** SAM and vit.D are both approved nutraceuticals with known safety profiles,this combination treatment may serve as a novel strategy to reduce breast cancer-associated morbidity and mortality。

关键词： metastasis vitamin inhibited

The effects of compressibility and strength on penetration of long rod and jet

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Defence Technology（防务技术） 2018年第2期14卷 99-108页

作者： Weng-jie Song Xiao-wei Chen Pu Chen department of Mechanics and engineering Science College of EngineeringPeking UniversityBeijing 100871China Centre for Applied Physics and Technology(CAPT) Peking UniversityBeijing 100871China State Key Lab of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

The approximate compressible model is adopted to study the effects of strength and compressibility on the penetration by WHA long rod and copper jet into semi-infinite target in detail. For WHA rod penetrating PMMA at 2 km/s v v velocity, whilst the effect of strength is weak and the effect of compressibility becomes stronger at higher impact velocity. For the copper jet penetrating 4030 Steel, 6061-T6 Al and PMMA. the virtual origin model is adopted, and the compressibility and strength are implicitly considered by the linear relation between the penetration velocity and impact velocity. The effects of compressibility and target resistance on penetration efficiency are studied. The results show that the target resistance has a significant effect on the penetration efficiency. Howver PMMA is much more compressible than copper and the huge difference of compressibility has a significant effect on the penetration by hypervelocity copper jet into PMMA.

关键词： Compressibility Strength Long rod Jet Compressible model virtual origin model

Enhanced ferroelectric polarization with less wake-up effect and improved endurance of Hf_(0.5)Zr_(0.5)O_(2)thin films by implementing W electrode

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Journal of Materials Science & Technology 2022年第9期104卷 1-7页

作者： Dao Wang Yan Zhang Jiali Wang Chunlai Luo Ming Li Wentao Shuai Ruiqiang Tao Zhen Fan Deyang Chen Min Zeng Jiyan Y.Dai Xubing B.Lu J-M.Liu Guangdong Provincial Key Laboratory of Quantum engineering and Quantum Materials and Institute for Advanced Materials South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou 510006China department of Applied Physics The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Laboratory of Solid State Microstructures and Innovation Centre of Advanced Microstructures Nanjing UniversityNanjing 210093China

This paper reports the improvement of electrical,ferroelectric and endurance of Hf_(0.5)Zr_(0.5)O_(2)(HZO)thinfilm capacitors by implementing W *** W/HZO/W capacitor shows excellent pristine 2 P_(r)values of 45.1 gC/cm^(2)at±6 v,which are much higher than those of TiN/HZO/W(34.4μC/cm^(2))and W/HZO/TiN(26.9μC/cm^(2))***,the maximum initial 2 P_(r)value of W/HZO/W capacitor can reach as high as 57.9μC/cm^(2)at±7.5 *** strong ferroelectric polarization effects are ascribed to the W electrode with a fairly low thermal expansion coefficient which provides a larger in-plane tensile strain compared with TiN electrode,allowing for enhancement of o-phase ***,the W/HZO/W capacitor also exhibits higher endurance,smaller wake-up effect(10.1%)and superior fatigue properties up to 1.5×10^(10)cycles compared to the TiN/HZO/W and W/HZO/TiN *** improvements of W/HZO/W capacitor are mainly due to the decreased leakage current by more than an order of magnitude compared to the W/HZO/TiN *** results demonstrate that capping electrode material plays an important role in the enhancement of o-phase formation,reduces oxygen vacancies,mitigates wake-up effect and improves reliability.

关键词： Hf_(0.5)Zr_(0.5)O_(2)films Ferroelectric polarization Endurance properties Thermal expansion coefficient W electrode

An efficient single atom catalysts Os/P_(3)C sheet for ammonia borane dehydrogenation

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Chinese Chemical Letters 2022年第6期33卷 3281-3286页

作者： Chaozheng He Quan Zhang Jinrong Huo Ling Fu Shaanxi Key Laboratory of Optoelectronic Functional Materials and Devices School of Materials Science and Chemical EngineeringInstitute of Environment and Energy CatalysisXi’an Technological UniversityXi’an 710021China School of Sciences Xi’an Technological UniversityXi’an 710021China College of Resources and Environmental engineering Tianshui Normal UniversityTianshui 741001China

Ammonia borane(NH_(3)BH_(3),AB)has been considered to be a promising chemical hydrogen storage *** on density functional theory,a series of transition metal atoms supported P_(3)C(P_(3)C_O)sheet is systematically investigated to screen out the most promising catalyst for dehydrogenation of *** results indicate that the Os/P_(3)C and Os/P_(3)C_O could be an efficient single atom catalyst(SACs)and the stepwise reaction pathway with free energy barrier of 2.07 and 1.54 e v ***,the rate constant further quantitatively confirmed the real situation of the first step of dehydrogenation of AB on the Os/P_(3)C and Os/P_(3)C_O *** found that k_(f1)at 400 K is equivalent to k_(f2)at 800 K,which greatly improves the temperature of the first step of AB dehydrogenation on P_(3)C_*** hope this work can provide a promising method for the design of catalysts for AB dehydrogenation reactions on the surface of two-dimensional materials(2D).

关键词： Ammonia borane Two-dimensional materials Dehydrogenation Single atom catalyst Microkinetic model

Promotion of the oxygen evolution performance of Ni–Fe layered hydroxides via the introduction of a proton-transfer mediator anion

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Science China Chemistry 2022年第2期65卷 382-390页

作者： Wenlong Li Fusheng Li Yilong Zhao Chang Liu Yingzheng Li Hao Yang Ke Fan Peili Zhang Yu Shan Licheng Sun State Key Laboratory of Fine Chemicals Institute of Artificial PhotosynthesisDUT-KTH Joint Education and Research Centre on Molecular DevicesDalian University of TechnologyDalian 116024China department of Chemistry School of Engineering Sciences in ChemistryBiotechnology and HealthKTH Royal Institute of TechnologyStockholm 10044Sweden Center of Artificial Photosynthesis for Solar Fuels School of ScienceWestlake UniversityHangzhou 310024China

Developing efficient catalysts with high durability and activity for the oxygen evolution reaction(OER)is imperative for sustainable energy conversion technologies,including hydrogen generation and CO_(2) reduction,as well as other electrochemical energy storage *** this end,a comprehensive understanding of the mechanism for the water oxidation reaction is ***,a surfactant,nonafluoro-1-butanesulfonate(FBS),was introduced into Ni-Fe layered double hydroxide(Ni Fe-FBS/CFP)via electrochemical deposition on the surface of a carbon fiber paper(CFP)*** as-prepared Ni Fe-FBS/CFP electrode exhibited excellent catalytic activities for OER compared to the Ni-Fe layered double hydroxide based electrode(Ni Fe-LDH/CFP),an excellent stability of 15 h,and an ultralow Tafel slope of 25.8 m v ***,by combining the results of p H-dependent kinetics investigations,chemical probing,proton inventory studies,and isotopic and atom-protontransfer measurements,it was observed that a proton-transfer process controls the reaction rates of both the Ni Fe-LDH and Ni Fe-FBS catalysts,and the residual sulfonate groups serve as proton transfer mediator to accelerate the proton transfer rate.

关键词： water splitting Ni Fe–LDH proton-coupled electron transfer proton transfer mediator sulfonate group

Damping Solitary Wave in a Three-Dimensional Rectangular Geometry Plasma

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Plasma Science and Technology 2016年第2期18卷 108-113页

作者：仁艳秋李滚段文山 School of Aeronautics and Astronautics University of Electronic Science and Technology of China department of Mechanical and Aerospace engineering Rutgers UniversityThe State University of New Jersey College of Physics and Electronic engineering and Joint Laboratory of Atomic and Molecular Physics of NWNU & IMP CAS Northwest Normal University

The solitary waves of a viscous plasma confined in a cuboid under the three types of boundary condition are theoretically investigated in the present *** introducing a threedimensional rectangular geometry and employing the reductive perturbation theory,a quasi-Kd v equation is derived in the viscous plasma and a damping solitary wave is *** is found that the damping rate increases as the viscosity coefficient increases,or increases as the length and width of the rectangle decrease,for all kinds of boundary ***,the magnitude of the damping rate is dominated by the types of boundary *** thus observe the existence of a damping solitary wave from the fact that its amplitude disappears rapidly for a → 0and b → 0,or ν→ ＋∞.

关键词： damping solitary wave viscous plasma reductive perturbation theory quasi-Kdv equation

Ultrathin Metal Silicate Hydroxide Nanosheets with Moderate Metal-Oxygen Covalency Enables Efficient Oxygen Evolution

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Energy & Environmental Materials 2022年第1期5卷 231-237页

作者： Jiexin Zhu Shikun Li Zechao Zhuang Shan Gao Xufeng Hong Xuelei Pan Ruohan Yu Liang Zhou Lyudmila v.Moskaleva Liqiang Mai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Institute of Applied and Physical Chemistry and Center for Environmental Research and Sustainable Technology University of Bremen department of Chemistry University of the Free State Collage of Chemistry & Chemical engineering Anhui University Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Xianhu Hydrogen Valleyfoshan guangdong 528200china

Exploring efficient,cost-effective,and durable electrocatalysts for electrochemical oxygen evolution reaction(OER)is pivotal for the large-scale application of water *** advance has demonstrated that the activity of electrocatalysts exhibits a strong dependence on the surface electronic ***,a series of ultrathin metal silicate hydroxide nanosheets(UMSHNs)M_(3)Si_(2)O_(5)(OH)_(4)(M=Fe,Co,and Ni)synthesized without surfactant are introduced as highly active OER *** silicate hydroxide nanosheets show an optimal OER activity with overpotentials of 287 and 358 m v at 1 and 10 m A cm^(-2),*** experimental and theoretical studies,it is found that the OER activity of UMSHNs is dominated by the metal-oxygen covalency(MOC).High OER activity can be achieved by having a moderate MOC as reflected by aσ^(*)-orbital(e_(g))filling near unity and moderate[3d]/[2p]***,the UMSHNs exhibit favorable chemical stability under oxidation *** contribution provides a scientific guidance for further development of active metal silicate hydroxide catalysts.

关键词： electrocatalysis metal silicate hydroxide metal-oxygen covalency oxygen evolution reaction ultrathin nanosheet