检索结果-南通市图书馆

Two-carrier transport in SrMnBi2 thin films

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2017年第3期12卷 61-72页

作者： Xiao yan Cheng Zhang Shan-Shan liu yan-wen liu David Wei Zhang Fa-Xian Xiu Peng Zhou State Key Laboratory of ASIC and System School of Microelectronics Fudan University Shanghai 200433 China State Key Laboratory of Surface Physics and Department of Physics Fudan University Shanghai 200433 China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093 China

Monocrystalline SrMnBi2 thin films were grown by molecular beam epitaxy （MBE）, and their transport properties were investigated. A high and unsaturated linear magnetoresistance （MR） was observed, which exhibited a transition from a semi-classical weak-field B2 dependence to a high-field linear dependence. An unusual nonlinear Hall resistance was also observed because of the anisotropic Dirac fermions. The two-carrier model was adopted to analyze the unusual Hall resistance quantitatively. The fitting results yielded carrier densities and mobilities of 3.75×10^14 cm^-2 and 850 cm^2·V^-1·s^-1, respectively, for holes, and 1.468×10^13 cm^-2, 4118 cm^2·V^-1·s^-1, respectively, for electrons, with a hole-dominant conduction at 2.5 K. Hence, an effective mobility can be achieved, which is in reasonable agreement with the effective hole mobility of 1800 cm^2·V^-1·s^-1, extracted from the MR. Further, the angle-dependent MR, proportional to cos 0, where 0 is the angle between the external magnetic field and the perpendicular orientation of the sample plane, also implies a high anisotropy of the Fermi surface. Our results about SrMnBi2 thin films, as one of a new class of AEMnBi2 and AEMnSb2 （AE = Ca, Sr, Ba, Yb, Eu） materials, suggest that they have a lot of exotic transport properties to be investigated, and that their high mobility might facilitate electronic device applications.

关键词： SrMnBi2 thin films magnetoresistance two carriers anisotropic Dirac fermions

Effect of nano-carbon black content on wetting phenomenon of molten steel and alumina-carbon ceramic filter substrates

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第8期31卷 1900-1913页

作者： Jin-wen Song wen yan Zhe Chen Ying liu Shao-song Hong The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina National-provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology Wuhan University of Science and TechnologyWuhan 430081HubeiChina Jiangsu Sheng Nai New Materials Co. Ltd.Taizhou 225503JiangsuChina

The effect of nano-carbon black content(O,8 and 12 wt.%)on the wettability of molten steel on Al_(2)O_(3)-C substrates was investigated by the sessile drop wetting method at 1500℃ under argon *** the beginning of the wetting experiment,the contact angle decreased with the increase in nano-carbon black *** the wetting experiment progressed,FeAl_(2)0_(4) layer and sheet Al_(2)O_(3) layer were found at the interface between the molten steel and the Al_(2)O_(3)-C substrates with O and 8 wt.% nano-carbon black content,and the contact angle deceased with *** the content of nano-carbon black was 12 wt.%,a large number of nano-Al_(2)O_(3) whiskers were observed,which made the contact angle between the molten steel and Al_(2)O_(3)-C substrate become *** on the scanning electron microscope and energy dispersive spectrometry results,the formation mechanism of FeAl2O4 layer and Al_(2)O_(3) layer and the interfacial reaction mechanism were proposed.

关键词： Contact angle Nano-carbon black Al_(2)O_(3)-C substrate Molten steel Interfacial reaction

Rare earth-based MOF@mesoporous silica nanoplatform for long-term and luminescence trackable chemotherapy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2022年第8期41卷 2701-2710页

作者： Lu-Min Wang wen-yan liu Ming-Liang Hu Jia-Sai Yao Ping Wang Jia-Hao liu Miao He Yi Gao Zhen-Xing Li Gastroenterology Department The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an710004China Digestive Diseases in Precision Medicine Institute The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an710004China State Key Laboratory of Heavy Oil Processing College of New Energy and MaterialsChina University of Petroleum(Beijing)Beijing102249China

Developing the multifunctional nanocarriers for long-term drug release and luminescence traceability is a challenging *** this task,we designed a novel nanoplatform for long-term and luminescence trackable chemotherapy,which is prepared via a hollow ZIF-8(where ZIF is zeolitic imidazolate frameworks)coated by the Eu^(3+)-doped mesoporous silica(ZIF-8@mesoporous silica).The hollow ZIF-8 is used as a drug library for loading the anticancer drug,and the pH-sensitive properties of ZIF-8 can targeted-release drugs in the tumor and cut down the poisonousness of drugs to normal *** shell layer of mesoporous silica can achieve the long-term drug release,which solves the problem of short drug circulation time in the body,reduces the drug administration frequency,and improves the therapeutic ***,the ZIF-8@mesoporous+doxorubicin(DOX)is injected only once during the 14-day *** addition,Eu^(3+)doped in mesoporous silica ensures luminescence tracking and detection of drug pathways in living ***,this nanoplatform provides a whole new strategy for the longterm treatment of tumors.

关键词： Rare earth ZIF-8 Mesoporous silica Long-term chemotherapy Luminescence traceability Nanocarrier

Research on casing deformation prevention technology based on cementing slurry system optimization

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第2期21卷 1231-1240页

作者： yan yan Meng Cai wen-Hai Ma Xiao-Chuan Zhang Li-Hong Han Yong-Hong liu State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials CNPC Tubular Goods Research InstituteXi©an710077ShaanxiChina College of Mechanical and Electrical Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province Chengdu610095SichuanChina CNPC Daqing Oilfield Company Daqing163453HeilongjiangChina

The casing deformation prevention technology based on the optimization of cement slurry is proposed to reduce the casing deformation of shale oil and gas wells during hydraulic fracturing. In this paper, the fracture mechanism of hollow particles in cement sheath was firstly analyzed by discrete element method, and the effect of hollow particles in cement on casing deformation was investigated by laboratory experiment method. Finally, field test was carried out to verify the improvement effect of the casing deformation based on cement slurry modification. The results show that the formation displacement can be absorbed effectively by hollow particles inside the cement transferring the excessive deformation away from casing. The particles in the uncemented state provide deformation space during formation slipping. The casing with diameter of 139.7 mm could be passed through by bridge plug with the diameter of 99 mm when the mass ratio of particle/cement reaches 1:4. According to the field test feedback, the method based on optimization of cement slurry can effectively reduce the risk of casing deformation, and the recommended range of hollow microbeads content in the cement slurry is between 15% and 25%.

关键词： Cement slurry Hollow ceramsite Casing deformation Formation slip Field test

Shear-thinning Catechol-modified Chitosan Hydrogel Loaded with Silver Nanoparticles for Endoscopic Submucosal Dissection

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第8期42卷 1147-1155页

作者： wen-Jun Feng yan-He Wu Xiao-yang liu Zheng-Ke Wang MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310058China

Shear-thinning hydrogels have emerged for endoscopic submucosal dissection,while wound intervention after surgery has rarely been ***,a catechol-modified chitosa n hydrogel with shear-thinning property was developed for simultaneously facilitating endoscopic submucosal dissection and postoperative wound *** from the shear-thinning and self-healing characteristics,the asprepared hydrogel showed easily endoscopic *** also performed very well as submucosal cushion,which could remain above 70%after injection for 120 min in ex vivo porcine large intestine *** fact,the cushion height of normal saline dramatically decreased to 46%of the initial height at 30 *** nanoparticles encapsulated into the network endowed the hydrogel with almost reached 100%antibacterial effect against *** and *** hemolysis ratio of the hydrogel was calculated to be as low as 0.8%.Combined with good hemocompatibility and cytocompatibility,the as-prepared hydrogel displayed much higher in vivo wound closu re and healing efficacy than normal *** results demonstrated the superiority of the shear-thinning chitosan hydrogel in facilitating clinical endoscopic submucosal dissection surgery.

关键词： Shear-thinning hydrogel Endoscopic mucosal dissection Wound healing Catechol-modified chitosan Silver nanoparticles

Cloning and sequence analysis of chitin synthase gene fragments of Demodex mites

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第10期13卷 763-768页

作者： Ya-e ZHAO Zheng-hang WANG yang XU Ji-ru XU wen-yan liu Meng WEI Chu-ying WANG Department of Immunology and Pathogen Biology Xi'an Jiaotong University College of MedicineXi'an 710061China

To our knowledge,few reports on Demodex studied at the molecular level are available at *** this study our group,for the first time,cloned,sequenced and analyzed the chitin synthase(CHS) gene fragments of Demodex folliculorum,Demodex brevis,and Demodex canis(three isolates from each species) from Xi'an China,by designing specific primers based on the only partial sequence of the CHS gene of *** from Japan,retrieved from *** show that amplification was successful only in three *** isolates and one *** isolate out of the nine Demodex *** obtained fragments were sequenced to be 339 bp for *** and 338 bp for *** CHS gene sequence similarities between the three Xi'an *** isolates and one Japanese *** isolate ranged from 99.7% to 100.0%,and those between four *** isolates and one *** isolate were 99.1%-99.4%.Phylogenetic trees based on maximum parsimony(MP) and maximum likelihood(ML) methods shared the same clusters,according with the traditional *** open reading frames(ORFs) were identified in each CHS gene sequenced,and their corresponding amino acid sequences were located at the catalytic *** relatively conserved sequences could be deduced to be a CHS class A gene,which is associated with chitin synthesis in the integument of Demodex mites.

关键词： Demodex Chitin synthase genes Cloning and sequencing Phylogenetic study Function analysis

Purification performance on molten steel of novel Al_(2)O_(3)-based ceramic filter prepared from microporous powder and nano-Al_(2)O_(3) powder

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第6期31卷 1535-1546页

作者： Zhe Chen wen yan Ying liu Guang-qiang Li Shao-song Hong Nan Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Jiangsu Shengnai New Materials Co. Ltd.Taizhou 225534JiangsuChina

Reticulated ceramic foam filters provide an effective way to purify molten steel by removing non-metallic *** proposed a novel strategy to improve the purification performance of Al_(2)O_(3)-based ceramic filters by using microporous corundum-spinel raw materials to replace dense raw *** kinds of Al_(2)O_(3)-based ceramic filters fabricated from dense α-Al_(2)O_(3) micro-powder or microporous corundum-spinel powder were selected to carry out the immersion tests with molten *** the one hand,the higher surface roughness of the filter skeleton prepared from microporous raw materials increased the adsorption capacity of skeleton surface on inclusions in molten *** the other hand,the higher apparent porosity and larger pore size of the filter skeleton were more beneficial to the penetration of molten steel in the micropores of *** reaction process at the solid-liquid interface also improved the wettability of the interface between skeleton and molten steel,resulting in a larger penetration depth and a better adsorption effect on the *** summary,the novel Al_(2)O_(3)-based ceramic filter prepared with microporous corundum-spinel powder and addition of 5 wt.% nano-Al_(2)O_(3) powder reduced the total oxygen content of the steel from 40.2×10^(-4) to 12.7×10^(-4) wt.% by 68.4% and the Al content from 0.46 to 0.18 wt.% by 60.9% after immersion test,presenting the most excellent purification performance on molten steel.

关键词： Al_(2)O_(3)-based ceramic filter Microporous corundum-spinel powder Non-metallic inclusion-Microstructure Molten steel purification

3D printed silicon-based micro-lattices with ultrahigh areal/gravimetric capacities and robust structural stability for lithium-ion batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第4期17卷 2693-2703页

作者： Jie Fu Dong Wang yan Li Xianzheng liu Rui Zhang Zhiyuan liu Pengdong liu Lijuan Zhang Xuefei Li Guangwu wen School of Materials Science and Engineering Shandong University of TechnologyZibo 255000China Shandong Si-Nano Materials Technology Co. Ltd.Zibo 255000China

Nanostructured silicon anodes have shown extraordinary lithium storage properties for lithium-ion batteries(LIBs)but are usually achieved at low areal loadings(<1.5 mg·cm^(-2))with low areal *** sound electrochemical performance at high loading requires proportionally higher ion/electron currents and robust structural stability in the thicker ***,we report a three-dimensional(3D)printed silicon-graphene-carbon nanotube(3D-Si/G/C)electrode for simultaneously achieving ultrahigh areal/gravimetric capacities at high mass *** periodically arranged vertical channels and hierarchically porous filaments facilitate sufficient electrolyte infiltration and rapid ion diffusion,and the carbonaceous network provides excellent electron transport properties and mechanical integrity,thus endowing the printed 3D-Si/G/C electrode with fast electrochemical reaction kinetics and reversibility at high mass ***,the 3D-Si/G/C with high areal mass loading of 12.9 mg·cm^(-2) exhibits excellent areal capacity of 12.8 mAh·cm^(-2) and specific capacity of 1007 mAh·g^(-1),***-situ optical microscope and ex-situ scanning electron microscope(SEM)confirm that the hierarchically porous filaments with interconnected carbon skeletons effectively suppress the volume change of silicon and maintain stable micro-lattice architecture.A 3D printed 3D-Si/G/C-1||3D-LiFePO_(4)/G full cell holds excellent cyclic stability(capacity retention rate of 78%after 50 cycles)with an initial Coulombic efficiency(ICE)of 96%.This work validates the feasibility of 3D printing on constructing high mass loading silicon anode for practical high energy-density LIBs.

关键词： silicon anode areal capacity three-dimensional(3D)printing lithium-ion batteries

Synergism of solar-driven interfacial evaporation and photo-Fenton Cr(Ⅵ) reduction by sustainable Bi-MOF-based evaporator from waste polyester

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第7期94卷 527-540页

作者： Zifen Fan Jie liu Huajian liu Lijie liu yan She Xueying wen Huiyue Wang Guixin Hu Ran Niu Jiang Gong Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureHubei Engineering Research Center for Biomaterials and Medical Protective MaterialsSemiconductor Chemistry CenterSchool of Chemistry and Chemical EngineeringHuazhong University of Science andTechnologyWuhan430074HubeiChina

The integration of interfacial solar steam generation and photocatalytic degradation technology has pro-vided a promising platform to simultaneously produce freshwater and degrade ***,con-structing low-cost,multi-functional evaporators for treating Cr(Ⅵ)-polluted water remains challenging,and the synergistic mechanism on Cr(Ⅵ)reduction is ***,we propose the combined strategy of ball milling and solution mixing for the sustainable production of Bi-MOF microrod from waste poly(ethylene terephthalate),and construct Bi-MOF-based solar evaporators for simultaneous photo-Fenton Cr(Ⅵ)reduction and freshwater ***,the evaporator comprised of Bi-MOF microrod and graphene nanosheet possesses high light absorption,efficient photothermal conversion,and good hydro-philic *** to the advantages,the hybrid evaporator exhibits the evaporation rate of 2.16 kg m^(-2) h^(-1) and evaporation efficiency of 87.5%under 1 kW m^(-2) of *** integrating with photo-Fenton reaction,the Cr(Ⅵ)reduction efficiency is 91.3%,along with the reaction kinetics of 0.0548 min^(-1),surpassing many advanced *** the outdoor freshwater production and Cr(Ⅵ)reduction,the daily accumulative water yield is 5.17 kg m^(-2) h^(-1),and the Cr(Ⅵ)reduction efficiency is 99.9%.Furthermore,we prove that the localization effect derived from the interfacial solar-driven evap-oration enhances H_(2)O_(2) activation for the photo-Fenton reduction of Cr(Ⅵ).Based on the result of density functional theory,Bi-MOF microrod provides rich active centers for H_(2)O_(2) activation to produce active sites such as e-or-O_(2).This study not only proposes a new strategy to construct multi-functional solar evaporators for freshwater production and catalytic reduction of pollutants,but also advances the chem-ical upcycling of waste polyesters.

关键词： Interfacial solar steam generation Cr(VI)reduction Photo-Fenton reaction Metal-organic framework Waste plastic upcycling