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Journal of Iron and Steel Research International 2021年第7期28卷 874-888页

作者： Hua zhang Yao-zha lv Chang Chen Rong-sheng Chen Yang Li Hong-wei Ni feng Zheng The State Key Laboratory of Refractories and Metallurgy Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of EducationWuhan University of Science and TechnologyWuhan 430081HubeiChina School of Chemical Engineering and Technology Wuhan University of Science and TechnologyWuhan 430081HubeiChina Nano-Science and Nano-Technology Research Center Materials Science and Engineering CollegeShanghai UniversityShanghai 200444China

A series of zinc oxide(ZnO)nanorods arrays with different morphologies are synthesized on stainless steel mesh via a facile electrodeposition *** influences of electrodeposition parameters on the diameter,length,density and morphology of obtained ZnO nanorods are investigated *** results indicate that the electrodeposition potential is the key factor for the morphology of the obtained ZnO nanorods,which further showed the effect on the photocatalytic property of the obtained ***,the prepared ZnO nanorods array exhibits an excellent photocatalytic activity for methylene blue(MB)in ultraviolet *** degradation efficiency for MB solution reaches 95.1%under the irradiation of ultraviolet light for 120 *** addition,the photocatalytic property of the prepared ZnO nanorods can be extended to the visible light region after the modified with graphene oxide(GO).The obtained GO/ZnO composite also shows remarkable photocatalytic activity and *** photodegradation efficiency for MB is 83.6%,and the catalytic performance retains 97.3% of its initial photocatalytic activity after five cycles.

关键词： Stainless steel mesh Zinc oxide Nanorod Graphene oxide Photocatalysis Methylene blue

The Influence of Chitin Nanocrystals on Structural Evolution of Ultra-high Molecular Weight Polyethylene/Chitin Nanocrystal Fibers in Hot-drawing Process

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Chinese Journal of Polymer Science 2016年第11期34卷 1373-1385页

作者： Min-fang An Hao-jun Xu You lv Li zhang Qun Gu feng Tian 王宗宝 Ningbo Key Laboratory of Specialty Polymers Faculty of Materials Science and Chemical Engineering Ningbo University Ningbo 315211 China College of Material Engineering Ningbo University of Technology Ningbo 3151006 China Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China

Ultra-high molecular weight polyethylene（UHMWPE）/chitin nanocrystal（CNC） fibers were prepared. Compared with the pure UHMWPE fibers, the ultimate tensile strength and Young＇s modulus of UHMWPE/CNC fibers are improved by 15.7% and 49.6%, respectively, with the addition of chitin nanocrystals（CNCs） of 1 wt%. The melting temperature（Tm） of UHMWPE/CNC fibers was higher than that of pure UHMWPE fibers. Pure UHMWPE fibers and UHMWPE/CNC fibers were characterized with respect to crystallinity, orientation and kebab structure by wide-angle X-ray diffraction（WAXD）, small-angle X-ray scattering（SAXS） and scanning electron microscopy（SEM）. It is found that the CNCs act as the shish structure in UHMWPE/CNC fibers and the kebab crystals are grown around the CNCs. There was almost no difference between pure UHMWPE fibers and UHMWPE/CNC fibers in orientation. But the degree of crystallinity of various stages of UHMWPE/CNC fibers was respectively higher than the corresponding stage of pure UHMWPE fibers. Moreover, the addition of 1 wt% CNCs improved the thickness of kebab crystals and accelerated the transformation of kebab to shish.

关键词： UHMWPE shish crystallinity modulus SAXS WAXD drawing melting chitin ultimate

Cloning and structural characterization of juvenile hormone diol kinase in Spodoptera litura

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Insect Science 2016年第6期23卷 819-828页

作者： Bao-Juan Zeng Yuan lv Li-Li zhang Li-Hua Huang Qi-Li feng Guangzhou Key Laboratory of Insect Development Regulation and Application Research School of Life Sciences South China Normal University Guangzhou 510631 China

Juvenile hormone （JH） is one of the key insect hormones that regulate metamorphosis. Juvenile hormone diol kinase （JHDK） is an enzyme involved in JH metabolism and catalyzes JH diol to form a polar end product, JH diol phosphate that has no JH activity. In this study, a JHDK complementary DNA （cDNA） was cloned from Spodoptera litura and the structure and expression of the gene was characterized. The cDNA was 714 base pairs in length and encoded a protein of 183 amino acids with a molecular mass of 21 kDa and an isoelectric point of 4.55. Based on the structure, three putative calcium binding motifs and guanosine triphosphate-binding motifs were predicted in the protein. Modeling of the 3-D structure showed that the protein consisted of eight α-helixes linked with loops, with no β-sheets. The gene was expressed in the epidermis, fat body and midgut of fifth and sixth instar larvae. The expression level in the epidermis was lower than in the fat body and midgut. The gene was expressed at higher levels at the early stages than in the later stages of fifth and sixth instar midgut and fat body. The results suggest that this gene may be involved in the regulation of the JH titer in larvae ofS. litura.

关键词： juvenile hormone juvenile hormone diol kinase metabolism Spodoptera litura

STOCHASTIC MAXIMUM PRINCIPLE FOR MIXED REGULAR-SINGULAR CONTROL PROBLEMS OF FORWARD-BACKWARD SYSTEMS

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Journal of Systems Science & Complexity 2013年第6期26卷 886-901页

作者： zhang feng School of Mathematics and Quantitative Economics Shandong University of Finance and Economics

This paper considers a stochastic optimal control problem of a forward-backward system with regular-singular controls where the set of regular controls is not necessarily convex and the regular control enters the diffusion *** control problem is difficult to solve with the classical method of spike *** authors use the approach of relaxed controls to establish maximum principle for this stochastic optimal control *** optimality conditions are also investigated.

关键词： Forward-backward system maximum principle relaxed control singular control.

Repair of sciatic nerve defects using tissue engineered nerves

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Neural Regeneration Research 2013年第21期8卷 1985-1994页

作者： Caishun zhang Gang lv Department of Hand and Foot Surgery First Affiliated Hospital of Liaoning Medical University

In this study, we constructed tissue-engineered nerves with acellular nerve allografts in Sprague-Dawley rats, which were prepared using chemical detergents-enzymatic digestion and mechanical methods, in combination with bone marrow mesenchymal stem cells of Wistar rats cultured in vitro, to repair 15 mm sciatic bone defects in Wistar rats. At postoperative 12 weeks, electrophysiological detection results showed that the conduction velocity of regenerated nerve after repair with tissue-engineered nerves was similar to that after autologous nerve grafting, and was higher than that after repair with acellular nerve allografts. Immunohistochemical staining revealed that motor endplates with acetylcholinesterase-positive nerve fibers were orderly arranged in the middle and superior parts of the gastrocnemius muscle; regenerated nerve tracts and sprouted branches were connected with motor endplates, as shown by acetylcholinesterase histochemistry combined with silver staining. The wet weight ratio of the tibialis anterior muscle at the affected contralateral hind limb was similar to the sciatic nerve after repair with autologous nerve grafts, and higher than that after repair with acellular nerve allografts. The hind limb motor function at the affected side was significantly improved, indicating that acellular nerve allografts combined with bone marrow mesenchymal stem cell bridging could promote functional recovery of rats with sciatic nerve defects.

关键词： neural regeneration peripheral nerve injury tissue engineering artificial nerve sciatic nerve defects bone marrow mesenchymal stem cells nerve scaffold grants-supported paper neuroregeneration

High-contrast imaging based on wavefront shaping to improve low signal-to-noise ratio photoacoustic signals using superpixel method

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Chinese Physics B 2020年第3期29卷 251-258页

作者： Xinjing lv Xinyu Xu Qi feng Bin zhang Yingchun Ding Qiang Liu College of Mathematics and Physics Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua UniversityBeijing 100084China

Photoacoustic(PA) imaging has drawn tremendous research interest for various applications in biomedicine and experienced exponential growth over the past decade. Since the scattering effect of biological tissue on ultrasound is two-to three-orders magnitude weaker than that of light, photoacoustic imaging can effectively improve the imaging ***, as the depth of imaging further increases, the incident light is seriously affected by scattering that the generated photoacoustic signal is very weak and the signal-to-noise ratio(SNR) is quite low. Low SNR signals can reduce imaging quality and even cause imaging failure. In this paper, we proposed a new wavefront shaping and imaging method of low SNR photoacoustic signal using digital micromirror device(DMD) based superpixel method. We combined the superpixel method with DMD to modulate the phase and amplitude of the incident light, and the genetic algorithm(GA) was used as the wavefront shaping algorithm. The enhancement of the photoacoustic signal reached 10.46. Then we performed scanning imaging by moving the absorber with the translation stage. A clear image with contrast of 8.57 was obtained while imaging with original photoacoustic signals could not be achieved. The proposed method opens new perspectives for imaging with weak photoacoustic signals.

关键词： photoacoustic imaging wavefront shaping superpixel method high contrast imaging

Application of the concept of continuous dopaminergic stimulation for the management of Parkinson's disease

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Neuroscience Bulletin 2013年第5期29卷 661-669页

作者： Qing lv Baorong zhang Department of Neurology Second Affiliated Hospital School of Medicine Zhejiang University

Continuous dopaminergic stimulation（CDS）is a prominent therapeutic concept for the treatment of Parkinson＇s disease（PD）,which proposes that continuous brain dopamine-receptor stimulation,rather than intermittent doses of oral L-dopa,prevents or manages L-dopa-induced dyskinesias（LIDs）.In the normal situation,dopaminergic neurons in the substantia nigra pars compacta fire tonically to keep the dopamine receptor stimulation at a steady-state *** when the dopaminergic pathway is impaired,the dopamine receptor stimulation becomes intermittent or *** pulsatile stimulation causes a series of gene and protein changes in striatal neurons,leading to alterations in the firing patterns of basal ganglia neurons that result in *** in animal models and clinical trials of PD have shown that approaches providing CDS,currently including patches,extended-release formulations of L-dopa or dopamine agonists,continuous delivery of apomorphine and duodenal L-dopa infusion,are associated with a decreased risk of *** this review,we summarize both preclinical and clinical evidence for the five methods that may provide CDS in theory and compare the advantages and disadvantages of these methods.

关键词： continuous dopaminergic stimulation application Parkinson's disease L-dopa-induced dyskinesias

Magnetic flux control of chiral Majorana edge modes in topological superconductor

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Science China(Physics,Mechanics & Astronomy) 2018年第12期61卷 89-94页

作者： Yan-feng Zhou Zhe Hou Peng lv XinCheng Xie Qing-feng Sun International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China

We study the transport of chiral Majorana edge modes(CMEMs) in a hybrid quantum anomalous Hall insulator-topological superconductor(QAHI-TSC) system in which the TSC region contains a Josephson junction and a cavity. The Josephson junction undergoes a topological transition when the magnetic flux through the cavity passes through half-integer multiples of magnetic flux quantum. For the trivial phase, the CMEMs transmit along the QAHI-TSC interface as without magnetic flux. However, for the nontrivial phase, a zero-energy Majorana state appears in the cavity, leading to that a CMEM can resonantly tunnel through the Majorana state to a different CMEM. These findings may provide a feasible scheme to control the transport of CMEMs by using the magnetic flux and the transport pattern can be customized by setting the size of the TSC.

关键词： Majorana fermions Josephson junction topological superconductor non-equilibrium Green's function

Re–Os and Pb isotope features of pyrite in the Shihangli graphite deposit:implications of coal-generated graphite mineralization in central Hunan,South China

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Acta Geochimica 2023年第5期42卷 895-911页

作者： Yong zhang Dongsheng Ma Jian-feng Gao Jiayong Pan Xupeng lv Guoqi Liu Fujun Zhong Xiaotian zhang Ying Liu State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Earth Sciences and Engineering Nanjing UniversityNanjing 210046China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Yunnan Institute of Geological Survey Kunming 650032China

The coal metamorphism in Central Hunan pro-vides valuable information about hydrothermal activity and water/rock *** how to collect age data on hydrothermal fluid systems is necessary for understanding the history and genetic mechanisms of large-scale coal-generated graphite *** Shihangli graphite deposit,formed by significant siliceous hydrothermal alteration,is the most distinctive in Central ***–Os dating of pyrite from the Shihangli graphite deposit demonstrates that the coal-generated graphite mineraliza-tion age is-127.6±3.8 *** on in-situ mineral analysis,the hydrothermal pyrite in the Shihangli graphite deposit is mostly enriched in Sb,As,Au,W,Ag,Cu,Pb,and *** on the pyrite Re–Os isochron,the initial(^(187)Os/^(188)Os)values of pyrite were 1.03±0.24 and the Os(t)values varied from 571.8 to *** from the Shihangli graphite deposit comprises a Pb isotope composition similar to that of the Madiyi Formation bulk rock and stibnite from the Xikuangshan Sb *** on the Re–Os,Sr,S,and Pb isotopic compositions of sul-fides in the graphite and Sb deposits in Central Hunan,the Madiyi Formation was likely the primary source of ore-forming elements(Sb,Au,and As).The Re–Os and Pb isotope compositions of pyrite most likely reflect when large-scale fluid migration and coal-generated graphite mineralization occurred in Central Hunan.

关键词： Pyrite Re–Os Pb isotope Graphite Central Hunan

Stable cycling of LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)/lithium metal batteries enabled by synergistic tuning the surface stability of cathode/anode

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Journal of Energy Chemistry 2023年第12期87卷 342-350,I0009页

作者： Chunli Li Xinyu zhang Zhuolin Yang Haijian lv Tinglu Song Shijie Lu Yuxiang zhang Tianwen Yang Fan Xu feng Wu Daobin Mu School of Materials Science&Engineering Beijing Key Laboratory of Environmental Science and EngineeringBeijing Institute of TechnologyBeijing 100081China College of Chemistry Beijing University of Chemical TechnologyBeijing 100029China Shenzhen BTR New Energy Technology Institute Co. LtdShenzhen 518118GuangdongChina

Ni-rich layered oxides(LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2))show great potential in long-range and low-cost lithiumion ***,due to the high surface sensitivity,their practical application is hindered by interfacial instability with electrolytes under high voltage for long cyclic ***,by combining both firstprinciple calculations and time-of-flight secondary ion mass spectrometry(TOF-SIMS),a novel surface fluorinated reconstruction(SFR)mechanism is proposed to improve the interfacial stability under high voltage,which could effectively regulate the surface fluoride species to desensitize the LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)*** demonstrate here that by tuning the ratio of fluoride species,the LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)/Li battery could achieve excellent long-term and high voltage performance(163.5 mA h g^(-1)at 0.5 C for 300 cycles under 4.4 V),while the controlled sample decayed to 125.4 mA h g^(-1)after 300 ***,the favorable cross-talk effect induced by SFR further facilitates the incorporation of suitable amounts of Ni ions into the construction of stable solid electrolyte interface(SEI)layer for anode ***,the ultra-long cycling stability under high voltage can be achieved by the robust cathode/electrolyte and Li/electrolyte interfaces,which results in excellent interfacial stability after long *** work provides new insights into the surface design of cathode materials and improves the stability of the electrode-electrode interface under high voltage.

关键词： Ni-rich layered oxides Surface fluorinated reconstruction Interfacial stability TOF-SIMS Cross-talk effect