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Glucose Biosensor Based on Carbon/PVC-COOH/Ferrocene Composite with Covalently Immobilized Enzyme

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Chinese Chemical Letters 2005年第10期16卷 1357-1360页

作者： chun Xiang li Yun Long zeng chun Ran TANG Chemistry and Chemical Engineering College Hunan University of Science and Technology Xiangtan 411201

A carbon/PVC-COOH/ferrocene composite electrode used for the determination of glucose has been prepared. The ferrocene acted as mediator was incorporated into the PVC-COOH polymer and the leakage could be prevented. The presence of carboxyl groups on the electrode surface allowed immobilizing enzyme via EDC and NHS. The ratio of PVC-COOH to graphite powder （w/w） has been studied. Amperometric determination of glucose has been performed at potential of 0.30 V vs SCE. The response time was 〈 15 s. The linear response range was of 0.1-20 mmol/L with a detection limit of 48μmol/L.

关键词： PVC-COOH ferrocene glucose oxidase glucose.

Impact wear properties of dissimilar joints between bainitic frogs and pearlite rails

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Journal of Iron and Steel Research International 2024年第1期31卷 275-287页

作者： Pin-yong zeng chun-guang Zuo Xiao-yu Zhang Wei li Tribology Research Institute Southwest Jiaotong UniversityChengdu610031SichuanChina

The impact wear behavior and damage mechanism of dissimilar welded joints between U26Mn frog and U75 V rail before and after normalizing treatment were studied by cyclic impact *** experiment indicated that the impact wear volume of the joints increased with the increasing number of impact *** main wear mechanisms include pitting wear,mild fatigue wear,delamination wear,and fatigue wear,and plastic deformation was the primary impact wear *** them,fatigue wear had the greatest influence on wear volume,while other wear mechanisms had limited *** impact wear resistance of the base material was better than that of the heat-affected *** treatment was beneficial to improving the impact wear resistance of welded joints owing to its effect to promote pearlite recovery,grain refinement,and uniform distribution of *** martensite generated in the rail welded joints aggravated the impact wear damage to the materials,which should be avoided.

关键词： Dissimilar welded joint Impact wear Bainitic steel Damage mechanism Wear rate

Nested Saturated Control of Uncertain Complex Cascade Systems Using Mixed Saturation Levels

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1163-1174页

作者： Meng li Zhigang zeng Wuhan National Laboratory for Optoelectronics Wuhan 430074 School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074 Key Laboratory of Image Processing and Intelligent Control of Education Ministry of China Wuhan 430074China

This study addresses the problem of global asymptotic stability for uncertain complex cascade systems composed of multiple integrator systems and non-strict feedforward nonlinear systems. To tackle the complexity inherent in such structures, a novel nested saturated control design is proposed that incorporates both constant saturation levels and state-dependent saturation levels. Specifically, a modified differentiable saturation function is proposed to facilitate the saturation reduction analysis of the uncertain complex cascade systems under the presence of mixed saturation levels. In addition, the design of modified differentiable saturation function will help to construct a hierarchical global convergence strategy to improve the robustness of control design scheme. Through calculation of relevant inequalities, time derivative of boundary surface and simple Lyapunov function,saturation reduction analysis and convergence analysis are carried out, and then a set of explicit parameter conditions are provided to ensure global asymptotic stability in the closed-loop systems. Finally, a simplified system of the mechanical model is presented to validate the effectiveness of the proposed method.

关键词： method saturation differentiable

Cationic surface polarization centers on ionic carbon nitride for efficient solar-driven H_(2)O_(2) production and pollutant abatement

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Chinese Chemical Letters 2024年第10期35卷 383-388页

作者： Zhenyu Hu Zhenchun Yang Shiqi zeng Kun Wang lina li chun Hu Yubao Zhao MOE Key Laboratory for Water Quality and Conservation of the Pearl River Delta Institute of Environmental Research at Greater BayGuangzhou UniversityGuangzhou510006China

Solar-driven H_(2)O_(2)production and emerging organic pollutants(EOPs)elimination are of great significance from the perspective of environmental *** efficiency of the photocatalytic reaction system is the key challenge to be *** this work,the strategy of constructing surface ionic local polarization centers to enhance the exciton dissociation of the polymeric photocatalytic is *** bipyridinium cation(TMAP)is complexed on a K^(+)-incorporated carbon nitride(CNK)framework,and the combination of local polarization centers both on the surface(bipyridinium cation)and bulk(K+cation)contributes to a superior photocatalytic H_(2)O_(2)production performance,affording a remarkable H_(2)O_(2)generation rate of 46.8μmol h^(-1)mg^(-1)and a high apparent quantum yield(AQY)value of 77.5%under irradiation of 405 nm *** substantiated experimentally by steady state/transient spectroscopy techniques,the surface local polarization centers increase the population of the long-lived trapped electrons,and thereby promote the interfacial charge transfer process for chemical conversion *** strategy is potentially applicable to the design of a wide range of efficient solar-to-chemical conversion systems.

关键词： Local polarization Oxygen reductionreaction Hydrogen peroxide production Pollutantdegradation Polymeric carbon nitride

Construction of a predictive model for acute liver failure after hepatectomy based on neutrophil-to-lymphocyte ratio and albuminbilirubin score

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1087-1096页

作者： Xiao-Pei li zeng-Tao Bao li Wang chun-Yan Zhang Wen Yang Department of Family Planning and Assisted Reproductive Technology The First People’s Hospital of LianyungangLianyungang 222000Jiangsu ProvinceChina Department of Gastrointestinal Surgery The First People’s Hospital of LianyungangLianyungang 222000Jiangsu ProvinceChina Department of Laboratory Medicine The First People’s Hospital of LianyungangLianyungang 222000Jiangsu ProvinceChina Department of Gynecology The First People’s Hospital of LianyungangLianyungang 222000Jiangsu ProvinceChina

BACKGROUND Acute liver failure(ALF)is a common cause of postoperative death in patients with hepatocellular carcinoma(HCC)and is a serious threat to patient *** neutrophil-to-lymphocyte ratio(NLR)is a common inflammatory indicator that is associated with the prognosis of various diseases,and the albumin-bilirubin score(ALBI)is used to evaluate liver function in liver cancer ***,this study aimed to construct a predictive model for postoperative ALF in HCC tumor integrity resection(R0)based on the NLR and ALBI,providing a basis for clinicians to choose appropriate treatment *** To construct an ALF prediction model after R0 surgery for HCC based on NLR and *** In total,194 patients with HCC who visited The First People’s Hospital of lianyungang to receive R0 between May 2018 and May 2023 were enrolled and divided into the ALF and non-ALF *** compared differences in the NLR and ALBI between the two *** risk factors of ALF after R0 surgery for HCC were screened in the univariate *** risk factors were analyzed by multifactorial logistic *** then constructed a prediction model of ALF after R0 surgery for HCC.A receiver operating characteristic curve,calibration curve,and decision curve analysis(DCA)were used to evaluate the value of the prediction *** Among 194 patients with HCC who met the standard inclusion criteria,46 cases of ALF occurred after R0(23.71%).There were significant differences in the NLR and ALBI between the two groups(P<0.05).The univariate analysis showed that alpha-fetoprotein(AFP)and blood loss volume(BLV)were significantly higher in the ALF group compared with the non-ALF group(P<0.05).The multifactorial analysis showed that NLR,ALBI,AFP,and BLV were independent risk factors for ALF after R0 surgery in *** predictive efficacy of NLR,ALBI,AFP,and BLV in predicting the occurrence of ALT after R0 surgery for HCC was average[area under the curve(AUC)NLR=0.767,AUCALB

关键词： Acute liver failure Hepatocellular carcinoma Hepatectomy Neutrophil-to-lymphocyte ratio Albumin-bilirubin score

Hydrothermal Synthesis and Characterization of a Novel Supramolecular Network Compound [Co(IN)_2(H_2O)_4](IN=Isonicotinate)

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Chemical Research in Chinese Universities 2002年第4期18卷 385-388页

作者： JIA Hong-bin YU Jie-hui DING Hong XU Ji-qing YE ling JING Wei-jieWANG Tie-gang XU Jia-ning QU Xue-jian li zeng-chun College of Chemistry and State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130023P.R.China Key Laboratory of Supramolecular Structure and Materials of Ministry of Education Jilin UniversityChangchun 130023P.R.China Department of Chemistry Inner Mongolia University for NationalitiesTongliao 028000P.R.China

A novel supramolecular compound, [Co(IN)_2(H_2O)_4](1), was synthesized by means of the hydrothermal method and its structure was characterized with elemental analysis, FT-IR spectrum, TGA and X-ray diffraction. Though the unit cell structure of the title compound is only monomeric, all these units as building blocks are assembled into a novel three-dimensional supramolecular network via the widely hydrogen-bonding and π-π stacking interactions.

关键词： Hydrothermal synthesis Cobalt(Ⅱ) complex X-Ray diffraction Isonicotinate Supramolecule

Achieving strength-ductility synergy in novel paramagnetic Fe-based medium-entropy alloys through deep cryogenic deformation

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Rare Metals 2024年第9期43卷 4493-4507页

作者： Hu-Wen Ma Yan-chun Zhao li Feng Tian-zeng liu Zhi-Qi Yu Bo Jin Wang-chun Duan Peter K.liaw Dong Ma State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals Lanzhou University of TechnologyLanzhou 730050China Wenzhou Pump and Valve Engineering Research Institute Lanzhou University of TechnologyWenzhou 325105China Iron and Steel Research Institute Jiuquan Iron and Steel CorporationJiayuguan 735100China Lanzhou Resources and Environment Voc-Tech University Lanzhou 730123China Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN 37996-2200USA Neutron Science Center Songshan Lake Materials LaboratoryDongguan 523808China

Cryogenic pre-deformation treatment has been widely used to effectively improve the comprehensive mechanical properties of steels and novel ***,the dislocation evolution and phase transformation induced by different degrees of deep cryogenic deformation are not yet fully *** this study,the effects of multiple cryogenic pre-treatments on the mechanical properties and deformation mechanisms of a paramagnetic Fe_(63.3)Mn_(14-)Si_(9.1)Cr_(9.8)C_(3.8)medium-entropy alloy(MEA)were investigated,leading to the discovery of a pretreated MEA that exhibits exceptional mechanical properties,including a fracture strength of 3.0 GPa,plastic strain of 26.1%and work-hardening index of *** addition,X-ray diffraction(XRD)and transmission electron microscopy(TEM)analyses revealed that multiple cryogenic pre-deformation treatments significantly increased the dislocation density of the MEA(from 9×10^(15)to 4×10^(16)m^(-2)after three pretreatments),along with a transition in the dislocation type from predominantly edge dislocations to mixed dislocations(including screw-and edge-type dislocations).Notably,this pretreated MEA retained its paramagnetic properties(μ_(r)lity enhancement of the MEA.

关键词： Deep cryogenic transformation Iron-based medium-entropy alloys Dislocation evolution Phase transformation Stacking fault energy

Stable graphene oxide-based lyotropic liquid crystals for interfacial lubrication

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Friction 2024年第5期12卷 954-967页

作者： Yumei GUO Hanglin li Jiusheng li Xiangqiong zeng Laboratory for Advanced Lubricating Materials Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai201210China University of Chinese Academy of Sciences Beijing100049China

Lyotropic liquid crystals have lubricating properties due to their ordered assembly and fluidity,whose mesogens are often characterized by amphiphilic *** the attention that graphene oxide(GO)has been studied as a novel amphiphilic lyotropic mesogen this decade,and GO applied as a lubrication additive has been demonstrated in both oil and water-based systems,little research reveals the interfacial lubrication of GO liquid crystals *** work reports that GO aqueous dispersion can form lyotropic liquid crystals above a specific critical concentration of 5.00 mg/mL,providing a form of stable water-based lubricant,which can keep stable for several months and can reduce friction by 37.3%and wear by 25.24%.The liquid crystal phase was verified by polarizing microscope and synchrotron radiation small-angle X-ray scattering,and its rheological properties and viscoelasticity were studied by interfacial *** formation of lyotropic liquid crystals can enhance the stability of GO aqueous dispersions at high density,simultaneously ensuring friction decrease and anti-wear *** is attributed to the stable nematic network by the ordered GO *** ordered assembly structure bears vertical shear force,therefore,reducing the *** is also assumed that the wide lateral size of graphene oxide promotes the nematic phase thus smoothes the graphene oxide film composed spontaneously under the coincidence of lamellar liquid crystal and 2D layered *** this work,the interlayer lubrication of GO was optimized,and the problem of GO dispersion sedimentation was solved by *** range of interfacial lubrication of GO aqueous dispersion has been expanded and the synergistic effect is conducive to the environmentally friendly lubricants.

关键词： lyotropic liquid crystal graphene oxide aqueous lubrication tribological behavior

Uniqueness Problem for the Backward Differential Equation of a Continuous-State Branching Process

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1825-1836页

作者： Pei Sen li zeng Hu li School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100872P.R.China School of Mathematical Sciences Beijing Normal UniversityBeijing 100875P.R.China

The distributional properties of a multi-dimensional continuous-state branching process are determined by its cumulant semigroup,which is defined by the backward differential *** provide a proof of the assertion of Rhyzhov and Skorokhod(Theory ***.,1970)on the uniqueness of the solutions to the equation,which is based on a characterization of the process as the pathwise unique solution to a system of stochastic equations.

关键词： Continuous-state branching process multi-dimensional backward differential equation stochastic equation generator