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Recovery of vanadium and molybdenum from spent petrochemical catalyst by microwave-assisted leaching

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International Journal of Minerals,Metallurgy and materials 2019年第1期26卷 33-40页

作者： Zhi-yuan ma Yong Liu ji-kui Zhou Mu-dan Liu zhen-zhen Liu Guangdong Institute of Resources Comprehensive Utilization Guangdong Academy of Sciences State Key Laboratory of Separation and Comprehensive Utilization of Rare Metals Guangdong Provincial Key Laboratory of Development and Comprehensive Utilization of Mineral Resources

The study of the leaching of vanadium(V) and molybdenum(Mo) from spent petrochemical catalysts in sodium hydroxide(NaO H) medium was performed using two approaches, namely, conventional leaching and microwave-assisted leaching methods. The influence of microwave power, leaching time, leaching temperature, and NaOH concentration on the leaching efficiency of spent petrochemical catalyst was investigated. Under microwave-assisted conditions(600 W, 10 min, 90°C, 2.0 mol·L^(-1) NaOH, and 0.20 g·mL^(-1) solid–liquid ratio), the leaching efficiencies of V and Mo reached 94.35% and 96.23%, respectively. It has been confirmed that microwave energy has considerable potential to enhance the efficiency of the leaching process and reduce the leaching time. It is suggested that the enhancement of the leaching efficiencies of V and Mo can be attributed to the existence of a thermal gradient between solid and liquid and the generation of cracks on the mineral surface.

关键词： microwave spent petrochemical catalyst vanadium molybdenum

magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility

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Nano-Micro Letters 2025年第2期17卷 401-416页

作者： Chen Li Leilei Liang Baoshan Zhang Yi Yang Guangbin ji School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China College of materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration ***,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption *** top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass ***,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric *** theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ***,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of ***,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

关键词： Microwave absorption Radar-infrared compatible stealth Wrinkled MXene magneto-dielectric synergy Multifunction

manufacture the conducting polymer with light

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Science China Chemistry 2025年第01期 8-9页

作者： Yang Li Tianyu Li Yan ji Baoguang Liu College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology) Nanjing University of Posts & Telecommunications

Poly(3,4-ethylenedioxythiophene) (PEDOT), heralded as the “king” of conducting polymers, is esteemed in bioelectronics for its mixed electronic and ionic conductivity, mechanical properties compatible with biological tissues, tunable healing ability and stability in diverse environments [1]. Based on additive manufacturing of three-dimensional structures,PEDOT realizes the implementation in the efficient production of flexible bioelectronics, the construction of intricate electrode-neural implantations, and the development of smart brain-computer-interfaces [2].

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Investigation of phosphate adsorption from an aqueous solution using spent fluid catalytic cracking catalyst containing lanthanum

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Frontiers of Environmental Science & Engineering 2018年第6期12卷 155-165页

作者： zhen Li Zhaofu Qiu ji Yang Benteng ma Shuguang Lu Chuanhui Qin State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process East China University of Science and TechnologyShanghai 200237China

Spent FCC catalyst with lanthanum is proposed as a novel P-removal adsorbent. The spent FCC catalyst exhibits 99% adsorption efficiency for low P-concentration wastewater (C0 <5.0 mg/L). High affinity, endothermic rea... 详细信息

关键词： Spent FCC catalyst Phosphate removal Adsorption Lanthanum

Exploring the potential of extrachromosomal DNA as a novel oncogenic driver

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Science China Life Sciences 2025年第1期 144-157页

作者： Huanbo Zhu Longtao Huangfu Junbing Chen jiafu ji Xiaofang Xing Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing) Division of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital & Institute Department of Gastrointestinal Cancer Center Peking University Cancer Hospital & Institute Department of Liver Surgery & Transplantation Liver Cancer InstituteZhongshan HospitalFudan University Key Laboratory of Carcinogenesis and Cancer Invasion Ministry of Education State Key Laboratory of Holistic Integrative management of Gastrointestinal Cancers Beijing Key Laboratory of Carcinogenesis and Translational ResearchDivision of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital & Institute

Extrachromosomal DNA(ecDNA) is a form of circular DNA mostly found in tumor cells. Unlike the typical chromosomal DNA, ecDNA is circular, self-replicating, and carries complete or partial gene fragments. Although ecDNA occurrence remains a rare event in cancer, recent studies have shown that oncogene amplification on ecDNA is widespread throughout many types of cancer, implying that ecDNA plays a central role in accelerating tumor evolution. ecDNA has also been associated with increased tumor mutation burden, chromosomal instability, and even tumor microenvironment remodeling. ecDNA may be crucial in influencing tumor heterogeneity, drug sensitivity,oncogenic senescence, and tumor immunogenicity, leading to a worsening prognosis for tumor patients. In this way, several clinical trials have been conducted to investigate the importance of ecDNA in clinical treatment. In this review, we summarize the biogenesis, characteristics, and current research methods of ecDNA, discuss the vital role of ecDNA-caused tumor heterogeneity in cancers, and highlight the potential role of ecDNA in cancer therapy.

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Analytic derivation of Monin-Obukhov similarity function for open atmospheric surface layer

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Science China(Physics,Mechanics & Astronomy) 2021年第3期64卷 73-83页

作者： Yong ji zhen-Su She State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing100871China

The Monin-Obukhov(MO)similarity functionφm of the atmospheric surface layer(ASL)describing the deviation from the log law of the canonical turbulent boundary layer because of thermal stratification has been traditionally determined *** study presents a unified analytic expression derived from a symmetry-based theory of wall turbulence,called structural ensemble dynamics(SED),which postulates a generalized dilation symmetry principle expressing the effect of the wall on turbulence,leading to an analytic multi-regimes expression for the mixing *** ASL in unstable and stable conditions(i.e.,UC and SC),a unified two-regime formula of the mixing length is proposed,leading to aφm,similar to the Businger-Dyer(BD)formula;with a simplified model energy balance equation,φm is completely specified with no free ***,the theory allows the study of the open ASL’s underlying additional physical processes such as bottom-up or top-down flux due to pressure variations *** that Tp is decomposed into shear-like and buoyancy-like components,we propose new explanations for two important features of typical ASL:a significantly smaller Karman constant of 0.36 and a varyingφm for SC mean speed *** theory is validated by the data obtained at Kansas and also at Qingtu Lake Observation Array in Northern China for a variety of heat flux *** conclusion,due to pressure variations,we assert that ASL is intrinsically open and that the current theory offers a new basis for its quantification.

关键词： Monin-Obukhov similarity theory open atmospheric surface layer boundary layer turbulence symmetry-based analysis

Effects of different Ca^(2+) behavior patterns in the electric field on membrane fouling formation and removal of trace organic compounds

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Journal of Environmental Sciences 2022年第1期34卷 292-300页

作者： zhen Du Min ji Ruying Li School of Environmental Science and Engineering Tianjin UniversityTianjin 300350China

The effects of Ca^(2+) on membrane fouling and trace organic compounds(TrOCs)removal in an electric field-assisted microfiltration system were investigated in the presence of Na^(+) alone for *** the electric field,negatively charged bovine serum albumin(BSA)migrated towards the anode far away from the membrane surface,resulting in a 42.9%transmembrane pressure(TMP)reduction in the presence of Na^(+) at 1.5 *** contrast,because of the stronger charge shielding of Ca^(2+),the electrophoretic migration of BSA was limited and led to a neglectable effect of the electric field(1.5 V)on membrane ***,under 3 V applied voltage,the synergistic effects of electrochemical oxidation and bridging interaction between Ca^(2+) and BSA promoted the formation of denser settleable flocs and a thinner porous cake layer,which alleviated membrane fouling with a 64.5%decrease in TMP and nearly 100%BSA *** Tr OCs elimination increased with voltage and reached29.4%–80.4%at 3 *** electric field could prolong the contact between Tr OCs and strong oxidants generated on the anode,which enhanced the Tr OCs ***,a stronger charge shielding ability of Ca^(2+) weakened the electric field force and thus lowered the Tr OCs removal.

关键词： Electric field Membrane fouling Ca^(2+) Flocs formation Trace organic compounds

Synthesis and Crystal Structure of 4-(4,6-dimethoxyl -pyrimidin-2-yl)-3-thiourea Carboxylic Acid Methyl Ester

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Chinese Journal of Structural Chemistry 2006年第2期25卷 168-172页

作者： HUANG jie SONG ji-Rong REN Ying-Hui XU Kang-zhen ma Hai-Xia Department of Chemical Engineering Shanxi Key Laboratory of Physico-inorganic Chemistry Northwest Univers＇ity Xi＇an 710069 China

The title compound 4-（4,6-dimethoxylpyrimidin-2-yl）-3-thiourea carboxylic acid methyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at the room temperature. The structure was characterized by elemental analysis and IR and determined by X-ray diffraction analysis＇ Crystallographic data： C9H12N4O4S, Mr = 272.29, monoclinic, space group C2/m with a = 1.6672（3）, b = 0.66383（12）, c = 1.1617（2） nm, β = 109.275（2）°, V = 1.2136（4） nm^3, Dc = 1.490 g/cm^3,μ = 0.281 mm^-1, F（000） = 568, Z = 4, R1 = 0.0341and wR2 = 0.1042.

关键词： 4-(4,6-dimethoxylpyrimidin-2-yl)-3-thiourea carboxylic acid methyl ester synthesis X-ray diffraction

Parametric Resonance Analyses for Spar Platform in Irregular Waves

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China Ocean Engineering 2018年第2期32卷 236-244页

作者： YANG He-zhen XU Pei-ji School of Engineering University of GlasgowGlasgow G128QQUnited Kingdom School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The parametric instability of a spar platform in irregular waves is analyzed. Parametric resonance is a phenomenon that may occur when a mechanical system parameter varies over time. When it occurs, a spar platform will have excessive pitch motion and may capsize. Therefore, avoiding parametric resonance is an important design requirement. The traditional methodology includes only a prediction of the mathieu stability with harmonic excitation in regular waves. However, real sea conditions are irregular, and it has been observed that parametric resonance also occurs in non-harmonic excitations. Thus, it is imperative to predict the parametric resonance of a spar platform in irregular waves. A Hill equation is derived in this work, which can be used to analyze the parametric resonance under multi-frequency excitations. The derived Hill equation for predicting the instability of a spar can include non-harmonic excitation and random phases. The stability charts for multi-frequency excitation in irregular waves are given and compared with that for single frequency excitation in regular waves. Simulations of the pitch dynamic responses are carried out to check the stability. Three-dimensional stability charts with various damping coefficients for irregular waves are also investigated. The results show that the stability property in irregular waves has notable differences compared with that in case of regular waves. In addition, using the Hill equation to obtain the stability chart is an effective method to predict the parametric instability of spar platforms. Moreover, some suggestions for designing spar platforms to avoid parametric resonance are presented, such as increasing the damping coefficient, using an appropriate RAO and increasing the metacentric height.

关键词： spar platform instability parametric resonance mathieu equation irregular waves dynamic responses