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LEARNING RATES OF KERNEL-BASED ROBUST CLASSIFICATION

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Acta Mathematica Scientia 2022年第3期42卷 1173-1190页

作者： shuhua wang Baohuai SHENG School of Information Engineering Jingdezhen Ceramic UniversityJingdezhen 333403China Department of Finance Zhejiang Yuexiu UniversityShaoxing 312030China Department of Applied Statistics Shaoxing UniversityShaoxing 312000China

This paper considers a robust kernel regularized classification algorithm with a non-convex loss function which is proposed to alleviate the performance deterioration caused by the outliers.A comparison relationship between the excess misclassification error and the excess generalization error is provided;from this,along with the convex analysis theory,a kind of learning rate is *** results show that the performance of the classifier is effected by the outliers,and the extent of impact can be controlled by choosing the homotopy parameters properly.

关键词： Support vector machine robust classification quasiconvex loss function learning rate right-sided directional derivative

Antioxidant effects of the orientin and vitexin in Trollius chinensis Bunge in D-galactose-aged mice

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Neural Regeneration Research 2012年第33期7卷 2565-2575页

作者： Fang An Guodong Yang Jiaming Tian shuhua wang College of Pharmacy Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina

Total flavonoids are the main pharmaceutical components of Trollius chinensis Bunge, and orientin and vitexin are the monomer components of total flavonoids in Trollius chinensis Bunge. In this study, an aged mouse model was established through intraperitoneal injection of D-galactose for 8 weeks, followed by treatment with 40, 20, or 10 mg/kg orientin, vitexin, or a positive control （vitamin E） via intragastric administration for an additional 8 weeks. Orientin, vitexin, and vitamin E improved the general medical status of the aging mice and significantly increased their brain weights. They also produced an obvious rise in total antioxidant capacity, superoxide dismutase, catalase, and glutathione peroxidase levels in the serum, and the levels of superoxide dismutase, catalase and glutathione peroxidase, Na＋-K＋-ATP enzyme, and Ca2＋-Mg2＋-ATP enzyme in the liver, brain and kidneys. In addition, they significantly reduced malondialdehyde levels in the liver, brain and kidney and lipofuscin levels in the brain. They also significantly improved the neuronal ultrastructure. The 40 mg/kg dose of orientin and vitexin had the same antioxidant capacity as vitamin E. These experimental findings indicate that orientin and vitexin engender anti-aging effects through their antioxidant capacities.

关键词： Trollius chinesis Bunge orientin vitexin total flavonoids in Trollius

Fabrication of ZnS/CdS Heterojunction by Using Bimetallic MOFs Template for Photocatalytic Hydrogen Generation

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Chemical Research in Chinese Universities 2020年第6期36卷 1032-1038页

作者： ZHU Yuxin JIANG Xing LIN Lin wang shuhua CHEN Chao Key Laboratory of Jiangxi Province for Environment and Energy Catalysis College of ChemistryNanchang UniversityNanchang 330031 P.R.China

A new ZnS/CdS heterojunction is constructed through the direct sulfurization of a metal ions exchanged Zn/Cd-MOF precursor(MOF=metal-organic framework material).The composition,structure,morphology,photoabsorption and photoelectric performance of the ZnS/CdS are characterized by powder X-ray diffraction(PXRD),scanning electron microscope(SEM),transmission electron microscope(TEM),diffuse reflection spectrum(DRS),photoelectric current(PEC),electrochemical impedance spectroscopy(El S)and photoluminescence(PL)*** the metal ions are highly orderly separated by the organic ligands and the inherent porosity of the Zn/Cd-MOF,the as-synthesized ZnS/CdS possesses a large surface area and intimate contact at the heterogeneous interface with uniform ZnS/CdS *** photocatalytic hydrogen evolution activity of the ZnS/CdS is investigated under visible light irradiation(A^420 nm).It exhibits enhanced photocatalytic performance that the optimal ZnS/CdS achieves a maximum average hydrogen production rate of 2348μmol·h^-1 g^-1.A possible electron transfer mechanism is therefore proposed by the analyses of the Mott-Schottky plots.

关键词： ZnS/CdS heterojunction Zn/Cd-MOF precursor Photocatalytic hydrogen evolution

Calcium ion pinned vanadium oxide cathode for high-capacity and long-life aqueous rechargeable zinc-ion batteries

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Science China Chemistry 2020年第12期63卷 1767-1776页

作者： Min Du Feng Zhang Xiaofei Zhang Wentao Dong Yuanhua Sang Jianjun wang Hong Liu shuhua wang State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China Institute for Advanced Interdisciplinary Research(iAIR) University of JinanJinan 250022China

Rechargeable aqueous zinc ion batteries (ZIBs),with the easy operation,cost effectiveness,and high safety,are emerging candidates for high-energy wearable/portable energy storage ***,the unsatisfactory energy density and undesired long-term cycling performance of the cathode hinder the development of ***,we report the chemical preintercalation of a small amount of calcium ions into V2O5 as the cathode *** cathode of Ca0.04V2O5·1.74H2O (CVO)was demonstrated to have a high specific capacity of 400 mA h g^-1at the current density of 0.05 A g^-1and 187 mA h g^-1at 10 A g^-1,along with impressive capacity retention (100%capacity retention at 10 A g^-1 for 3,000 cycles).Meanwhile,the CVO//Zn battery exhibits a high energy density of 308 Wh kg^-1and a power density of 467 W kg^-1at 0.5 A g^-*** superior performance originates from the pinning effect of the calcium ions and the lubricating effect of the structural *** energy storage mechanism of the CVO cathode was also investigated in *** new phase (Zn3(OH)2V2O7·2H2O) generated upon cycling participates in the electrochemical reaction and thus contributes to the excellent electrochemical *** small amount of Ca^2+ pre-inserted into the interlayer of V2O5 sheds light on constructing cathodes with high energy density for ZIBs.

关键词： aqueous zinc-ion battery ion pre-intercalation vanadium pentoxide phase transition energy storage mechanism

Fabrication of Mesoporous SiO_(2)@CaSiO_(3) Hollow Spheres as Carriers for pH-sensitive Drug Delivery

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Chemical Research in Chinese Universities 2022年第4期38卷 999-1004页

作者： YUAN Mingwei SHI Shunli LUO Yanping YU Ying wang shuhua CHEN Chao Key Laboratory of Jiangxi Province for Environment and Energy Catalysis College of ChemistryNanchang UniversityNanchang330031P.R.China

Hollow mesoporous silica(HM-SiO_(2))was prepared by the improved stober *** this basis,HM-SiO_(2) was dispersed in an alkaline solution for surface ***,calcium source was introduced to combine with SiO_(3)^(2−) on the surface to form a CaSiO_(3) shell layer and an unprecedent SiO_(2)@CaSiO_(3) sphere with a hollow double-shell structure was *** as-synthesized SiO_(2)@CaSiO_(3) was characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),N_(2)-BET,IR and UV-Vis techniques,and its sustained release capacity of doxorubicin(DOX)loading was *** drug loading capacity can be achieved to 0.692 mg DOX/mg SiO_(2)@CaSiO_(3),exhibiting pH-responsivity under low pH conditions.

关键词： Hollow nano-sphere SiO_(2)@CaSiO_(3) Drug delivery pH-sensitive

Late Paleozoic-Early Mesozoic tectonic evolution of the Paleo-Asian Ocean： geochronological and geochemical evidence from granitoids in the northern margin of Alxa, Western China

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Frontiers of Earth Science 2018年第1期12卷 191-214页

作者： Xin SHA Jinrong wang Wanfeng CHEN Zheng LIU Xinwei ZHAI Jinlong MA shuhua wang School of Earth Sciences Gansu Key Laboratory of Mineral Resources in Western China Lanzhou University Lanzhou 730000 China State Key Laboratory for Mineral Deposits Research Nanjing University Nanjing 210000 China

The Paleo-Asian Ocean （Southern Mongolian Ocean） ophiolitic belts and massive granitoids are exposed in the Alxa block, in response to oceanic subduction processes. In this work, we report petrographic, geochem- ical, and zircon U-Pb age data of some granitoid intrusions from the northern Alxa. Zircon U-Pb dating for the quartz diorite, tonalite, monzogranite, and biotite granite yielded weighted mean 206pb/238U ages o f 302 ±9.2 Ma, 246.5±54.6 Ma, 235±4.4 Ma, and 229.5±5.6 Ma, respectively. The quartz diorites （-302 Ma） exhibit geochemical similarities to adakites, likely derived from partial melting of the initially subducted Chaganchulu back-arc oceanic slab. The tonalites （-246.5 Ma） display geochemical affinities of I-type granites. They were probably derived by fractional crystallization of the modified lithospheric mantle-derived basaltic magmas in a volcanic arc setting. The monzo- granites （-235 Ma） are characterized by low A1203, but high Y and Yb with notably negative Eu anomalies. In contrast, the biotite granites （-229.5 Ma） show high A1203 but low Y and Yb with steep HREE patterns and the absence of negative Eu anomalies. Elemental data suggested that the biotite granites were likely derived from a thickened lower crust, but the monzogranites originated from a thin crust. Our data suggested that the initial subduction of the Chaganchulu oceanic slab towards the Alxa block occurred at - 302 Ma. This subduction process continued to the Early Triassic （-246 Ma） and the basin was finally closed before the Middle Triassic （-235 Ma）. Subsequently, the break-off of the subducted slab triggered asthenosphere upwelling （240-230 Ma）.

关键词： Paleo-Asian Ocean ALxa granite geochemistry

Experimental Study of Motion of Nitrogen Taylor Bubbles and Liquid Slugs in Inclined Tubes

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Chinese Journal of Aeronautics 2009年第4期22卷 349-354页

作者： Zhang Hua,wang shuhua,wang Jing Institute of Engineering Thermo-physics,Shanghai Jiao Tong University,Shanghai 200240,China Institute of Engineering Thermo-physics Shanghai Jiao Tong University Shanghai 200240 China

This article studies rising velocity of Taylor bubbles and liquid slugs in liquid nitrogen at different axial positions in upward inclined tubes by means of a high speed motion analyzer. The bottom-closed tubes in the experiments are 1.0 m long with an inner diameter of 0.014 m or 0.018 m. The tube inclines upward from 0~ to 50~ with respect to the normal. Statistical method is used to analyze the data of the Taylor bubble and the liquid slug velocity. Reflecting the effects of the inclination angle on the rising velocity of Taylor bubbles and liquid slugs, the experimental results indicate the similar trend the Taylor bubble velocity and the liquid slug velocity have： it increases first, and then decreases with the increase of the inclination angle. Moreover, with the increase of the inclination angle, the liquid slug velocity becomes greater than Taylor bubble velocity.

关键词： cryogenic two-phase flow rising velocity high speed motion analyzer liquid nitrogen Taylor bubble liquid slug inclined tube

NaOH/Urea Swelling Treatment and Hydrothermal Degradation of Waste Cotton Fiber

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Journal of Renewable Materials 2020年第6期8卷 703-713页

作者： Lixia Gao Sheng Shi Wensheng Hou shuhua wang Zhifeng Yan Chao Ge College of Textile Engineering Taiyuan University of TechnologyJinzhong030600China Jihua 3542 Textile Company Limited Xiangyang441000China

In this study,waste cotton fabric was used as cellulose raw material and pretreated in aqueous NaOH/urea solution system to investigate the effect of NaOH/urea pretreatment solution on the hydrolysis of cotton *** cotton fiber was pretreated with different conditions of aqueous NaOH/urea solution,and the pretreated cotton fiber was hydrolyzed under the same conditions as the original cotton *** results of characterization analysis showed that water retention value of pretreated cotton fiber was higher than that of unpretreated ***,the cotton fiber presented both a convoluted structure and a coarser surface,XRD results suggested that the crystallinity degree of cellulose decreased dramatically,more cellulose II appeared,and the hydrogen bond is *** the different pretreatment conditions,the pretreatment effect was the best when the reaction temperature was 0°C,the solid-liquid ratio was 2:50,and the NaOH/urea ratio was 7:*** hydrolysis experiments of pretreated and unpretreated cotton fibers showed that when the hydrothermal temperature was 230°C,the heat preservation was 2 h,and the hydrochloric acid concentration was 5 wt.%,the glucose yield reached 29.99%.H+could catalyze the hydrolysis of cotton fiber more effectively due to damage to crystal structure and hydrogen bonds.

关键词： Waste cotton fibers NaOH/urea pretreatment hydrolyze recycling and reusing

Aerosol observation in Fengtai area,Beijing

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Particuology 2008年第3期6卷 214-217页

作者： Zengdong Liu Jianguo Liu Bei wang Fan Lu shuhua Huang Dexia Wu Daowen Hart Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics CAS Hefei 230031 China

Measurements of aerosol number concentration and particulate matter with diameter less than 10 μm （PM10） mass concentrations of urban background aerosols were performed in Fengtai area, Beijing in 2006. Black carbon （BC） was collected simultaneously from the ground and analyzed to determine the particulate matter components. To satisfy the interest in continuous monitoring of temporal and spatial distribution of aerosols, the relationship between extinction coefficient （visibility） measured by lidar remote sensing and the aerosol number concentration measured from the ground was derived by using statistical method. Vertical particle number concentration profile within the planetary boundary layer could be inversed through the lidar data as well as the statistical relation.

关键词： Number concentration Aerosol components Extinction coefficient Vertical distribution