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Journal of Materials Science & Technology 2024年第3期170卷 246-254页

作者： ze pu wang WenHong Ruan MinZhi Rong MingQiu Zhang Key Laboratory for Polymeric Composite and Functional Materials of MOE GD HPPC LabIGCMESchool of ChemistrySun Yat-Sen UniversityGuangzhou 510275China

To tackle the challenge of producing highly filled polymer composites using the traditional injection molding technique,which is characterized by the fairly high melt viscosity that makes mold filling difficult,the authors propose a solution based on dynamic covalent *** demonstrated by the proof-of-concept experiments,the 4-arm starshaped polycaprolactone(PCL)oligomers and microcrystalline cel-lulose(MCC)are crosslinked by the reversible Diels-Alder(DA)*** flowability of the compounds greatly decreases due to the dissociation of the intercomponent DA bonds at the retro-reaction tempera-ture,and the networked architecture is reconstructed during cooling as a result of the forward DA ***,the high-loading MCC fillers are well distributed in the matrix and covalently bonded to the nearby PCL,forming a striking contrast to the control in which linear PCL acts as the *** DA bonds crosslinked biodegradable PCL composites exhibit decent mechanical strength(20.7 MPa)even at the MCC fraction of 65 wt%,which is superior to those(5-12.2 MPa)of the highly filled PCL composites(with filler contents of 50-63.8 wt%)reported so *** proposed approach has sufficient expansibility for the fabrication of the highly filled polymer composites constructed by other types of matrix and fillers.

关键词： Polymer composites Microcrystalline cellulose Polycaprolactone Injection molding Dynamic reversible chemistry

The effect of bladder function on the efficacy of transurethral prostatectomy in patients with benign prostatic hyperplasia:a retrospective,single-center study

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Asian Journal of Andrology 2024年第1期26卷 112-118页

作者： Jin Li Xian-Yan-Ling Yi ze-Yu Chen Bo Chen Yin Huang Da-Zhou Liao pu-ze wang De-Hong Cao Jian-Zhong Ai Liang-Ren Liu West China School of Medicine Sichuan UniversityChengdu 610041China Department of Urology Institute of UrologyWest China HospitalSichuan UniversityChengdu 610041China

We investigated the impact and predictive value of bladder function in patients with benign prostatic hyperplasia(BPH)on the efficacy of transurethral ***,imaging,and urodynamic data of patients who underwent transurethral prostatectomy at West China Hospital of Sichuan University(Chengdu,China)from July 2019 to December 2021 were ***-up data included the quality of life(QoL),International Prostate Symptom Score(IPSS),and IPSS storage and voiding(IPSS-s and IPSS-v).Moreover,urinary creatinine(Cr),nerve growth factor(NGF),brain-derived neurotrophic factor(BDNF),and prostaglandin estradiol(PGE2)were measured in 30 patients with BPH and 30 healthy *** indicators were determined by subgroup analyses and receiver operating characteristic(ROC)curve *** the 313 patients with BPH included,patients with severe micturition problems had more improvements but higher micturition grades postoperatively than those with moderate ***,good bladder sensation,compliance,and detrusor contractility(Dc)were predictors of low postoperative IPSS and *** urinary concentrations of BDNF/Cr,NGF/Cr,and PGE2/Cr in patients were significantly higher than those in healthy participants(all P<***1).After evaluation,only DC was significantly related to both urinary indicators and postoperative recovery of *** with good DC,as predicted by urinary indicators,had lower IPSS and IPSS-v than those with reduced DC at the 1st month postoperatively(both P<0.05).In summary,patients with impaired bladder function had poor *** combined levels of urinary BDNF/Cr,NGF/Cr,and PGE2/Cr in patients with BPH may be valid predictors of preoperative bladderfunction and postoperative recovery.

关键词： BPH function of bladder IPSS:urodynamics

Microstructure and wear behavior of IC10 directionally solidified superalloy repaired by directed energy deposition

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Journal of Materials Science & Technology 2021年第34期93卷 71-78页

作者： Guan Liu Dong Du Kaiming wang ze pu Dongqi Zhang Baohua Chang State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China

Directed energy deposition has been used to repair superalloy components in aero engines and gas ***,the microstructure and properties are generally inhomogeneous in components because of the different processing ***,the microstructures and wear behavior of different zones(substrate,HAZ,and deposit)are investigated for the IC10 directionally solidified superalloy repaired by the directed energy deposition *** is found that the microstructure of the deposited layers is strongly textured with a-fiber texture in the building direction,and the texture intensity is continuously increased along the building *** kinds ofγ’phase(primary and secondaryγ’phase)can be found in the heat-affected zone(HAZ),and the average size of primaryγ’phase is smaller than that in the substrate due to *** the deposit layers,the size ofγ’phase is much smaller than those in the substrate and the primaryγ’phase of HAZ;both size and the fraction of theγ’phase decreases with the increase of building *** wear rate of the substrate is the smallest,indicating the best wear resistance;while the wear rate of HAZ is the largest,indicating the worst wear resistance in the repaired *** wear rates in the deposit layers increase from the bottom to the top zones,showing a decreasing wear *** wear is found to be the dominant wear mechanism of the repaired alloy,and the resistance to which is closely related to the fraction ofγ’phase in the *** understanding of the influence of microstructure on wear resistance allows for a more informed application of inhomogeneous superalloy components repaired by directed energy deposition in industry.

关键词： Directed energy deposition Directionally solidified superalloy Microstructure Wear behavior Repairing

Improvement of tensile superelasticity by aging treatment of NiTi shape memory alloys fabricated by electron beam wire-feed additive manufacturing

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Journal of Materials Science & Technology 2023年第14期145卷 185-196页

作者： ze pu Dong Du Dongqi Zhang Zixiang Li Shuai Xue Rui Xi Xiebin wang Baohua Chang Department of Mechanical Engineering State Key Laboratory of TribologyTsinghua UniversityBeijing 100084China Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJingshi Road 17923Jinan 250061China

For the first time,this work comprehensively studied the effectiveness of precipitation hardening achieved by aging treatment in improving the tensile superelasticity of NiTi alloys fabricated by elec-tron beam wire-feed additive manufacturing(EBAM),which possesses inherent advantages in producing dense and oxidation-free *** treatments under three temperatures(450,350,and 250℃)and different durations were conducted,and the resultant performance of tensile superelasticity,together with the corresponding evolution of precipitation and phase transformation behavior were investigated for the EBAM-fabricated NiTi *** showed that by appropriate aging treatment,EBAM fabricated NiTi alloys could achieve excellent recovery rates of approximately 95%and 90%after the 1st and 10th load/unload cycle for a maximum tensile strain of 6%,which were almost the highest achieved so far by AM processed NiTi alloys and close to those of some conventional NiTi *** improvement of tensile superelasticity benefited from the fine and dispersive Ni4Ti3 precipitates,which could be introduced by aging at 350℃ for 4 h or at 250℃ for 200 ***,the large amount of Ni4Ti3 precipitates would promote the intermediate R-phase transformation and bring a two-stage or three-stage transformation sequence,which depended on whether the distribution of the precipitation was homogeneous or *** work could provide guidance for the production of NiTi alloys with good tensile superelasticity by EBAM or other additive manufacturing processes.

关键词： NiTi shape memory alloys Electron beam Additive manufacturing Aging treatment Tensile superelasticity

Surface Trace Gases at a Rural Site between the Megacities of Beijing and Tianjin

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Atmospheric and Oceanic Science Letters 2014年第3期7卷 230-235页

作者： RAN Liang LIN Wei-Li wang pu-Cai DENG Zhao-ze Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences Centre for Atmosphere Watch and Services Meteorological Observation Centre China Meteorological Administration

The North China Plain(NCP) has recently faced serious air quality problems as a result of enhanced gas pollutant emissions due to the process of urbanization and rapid economic *** explore regional air pollution in the NCP,measurements of surface ozone(O3),nitrogen oxides(NOx),and sulfur dioxide(SO2) were carried out from May to November 2013 at a rural site(Xianghe) between the twin megacities of Beijing and *** highest hourly ozone average was close to 240 ppbv in May,followed by around 160 ppbv in June and *** ozone episodes were more notable than in 2005 and were mainly associated with air parcels from the city cluster in the hinterland of the polluted NCP to the southwest of the *** NOx,an important ozone precursor,the concentrations ranged from several ppbv to nearly 180 ppbv in the summer and over 400 ppbv in the *** occurrence of high NOx concentrations under calm conditions indicated that local emissions were dominant in *** double-peak diurnal pattern found in NOxconcentrations and NO/NOx ratios was probably shaped by local emissions,photochemical removal,and dilution resulting from diurnal variations of surface wind speed and the boundary layer height.A pronounced SO2 daytime peak was noted and attributed to downward mixing from an SO2-rich layer above,while the SO2-polluted air mass transported from possible emission sources,which differed between the non-heating(September and October) and heating(November) periods,was thought to be responsible for night-time high concentrations.

关键词： ozonenitrogen oxidessulfur dioxideNorth China Plain

GISAXS and ATR-FTIR Studies on Stress-Induced Microstructure Evolution of a-Si:H under H2 Plasma Exposure

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Chinese Physics Letters 2012年第10期29卷 167-170页

作者： ZUO ze-Wen CUI Guang-Lei wang Yu wang Jun-Zhuan pu Lin SHI Yi College of Physics and Electronics Information Anhui Normal UniversityWuhu 241000 School of Electronic Science and Engineering and Key Laboratory of Photonic and Electronic MaterialsNanjing UniversityNanjing 210093

Microstructure evolution in the surface layer of hydrogenated amorphous silicon(a-Si:H)film exposed to H2 plasma is investigated using grazing-incidence small-angle x-ray scattering and attenuated total reflection-Fourier transform infrared *** hydrogen generated in the microvoids through H-abstraction reaction drives the evolution of the void shape from spherical to ellipsoidal as well as increases the average void volume and total void volume ***-pressure H_(2) in the microvoid promotes the formation of a strained structure with high compressive stress within the a-Si:H film,which favours the generation of the SiHn complex in the subsurface layer of the a-Si:H film by H insertion into strained Si–Si bonds.

关键词： spectroscopy Microstructure strained

Powerful 2 μm Silica Fiber Sources: A Review of Recent Progress and Prospects

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Journal of Electronic Science and Technology 2015年第4期13卷 315-327页

作者： Xiao-Xi Jin Xiong wang pu Zhou Hu Xiao ze-Jin Liu the College of Optoelectronic Science and Engineering National University of Defense Technology

A review on the progress of powerful 2 μm silica fiber sources in past decades is presented. We review the state-of-the-art records and representative achievements of 2 μm high-average-power continuous- wave, pulsed fiber lasers and amplifiers, and powerful superfluorescent sources. Challenges which limit the further power scaling of 2 μm silica fiber sources are discussed, including pumping brightness limitation, thermal problem and nonlinear effects. Potential and promising roadmaps to go beyond these limitations, like tandem pumping and beam combining, are discussed. Prospects of powerful 2 μm silica fiber sources are also presented in the end of paper.

关键词： Doped fiber amplifiers fiber lasers,high power amplifiers infrared spectra.

Enhanced corrosion protection of magnesium alloy via in situ Mg-Al LDH coating modified by core-shell structured Zn-Al LDH@ZIF-8

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Rare Metals 2022年第8期41卷 2745-2758页

作者： pu-Bo Li Yong-Xun wang ze-Xi Shao Bin-Tao Wu Heng Li Mang-Mang Gao Kuan-Guan Liu Ke-Ren Shi Ningxia Key Laboratory of Photovoltaic Materials Ningxia UniversityYinchuan750021China School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW2522Australia China Special Equipment Inspection and Research Institute Beijing100029China State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan750021China

The Mg-Al layered double hydroxide(LDH)conversion coatings were first synthesized in situ to modify the AZ91 D alloy through urea hydrolysis to adjust the pH values(9.4,10.4,11.2 and 11.4).The pH 11.2 Mg-Al LDH possessed the best compactness and good crystallinity compared to other in situ LDH coatings and obtained the lowest corrosion current density(i_(corr))of(2.884×10^(-6)±0.345×10^(-6))A·cm^(-2),which was attributed to the anion-exchange reaction of LDH and the physical barrier against corrosion owing to the twisted penetration pathway of the interlaced LDH ***-shell structured Zn-Al LDH@ZIF-8 powder modified with stearic acid(SA)was further wrapped with polyvinylidene fluoride(PVDF)to prepare a hydrophobic double-layered coating on the underlying pH 11.2 Mg-Al LDH(SLLZ).The water contact angle(CA)of the SLLZ coating reached 105.6°,and its i_(corr)decreased to(3.524×10^(-7)±0.214×10^(-7))A·cm^(-2)compared with a single pH 11.2 *** SLLZ coating exhibited high durability and corrosion protection,even after15 days of immersion in NaCl *** PVDF,SA and ZIF-8 nano-shells contributed to good hydrophobicity,effectively forming a physical *** Zn-Al LDH core and underlying in situ Mg-Al LDH were beneficial for synergistically promoting anion-exchange reaction between the intercalated anions of LDH and chlorides in corrosive *** work provides a promising approach that combines core-shell LDH@ZIF-8 with LDH film on a Mg alloy surface to construct a hydrophobic film with excellent longterm anti-corrosion performance.

关键词： Mg alloy Layered double hydroxide Corrosion protection Coating Metal-organic frameworks

Enhancing electrocatalytic reduction of CO_(2)to C_(2+)products with high efficiency at Cu^(0)/Cu^(δ+)interfaces via iodine modification strategy

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Rare Metals 2024年第11期43卷 5747-5756页

作者： Shao-Song Ding Xing-pu wang Ming-Wei Fang Rong Zhang Zi-Hao Huang ze-Wen wang Mei-Ling wang Ying Zhu Wen-Xiu Jiang Xiao-Chen Feng Ying Zhu Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology School of Chemistry Beihang UniversityBeijing 100191China Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijing 100191China

Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to produce multicarbon(C_(2+))products over Cubased catalysts represents an ideal approach for renewable energy storage and carbon emissions *** Cu^(0)/Cu^(δ+)interfaces are widely recognized as crucial sites that promote C-C coupling and enhance the generation of C2+***,a major challenge arises from the tendency of Cu^(δ+)active sites within Cu^(0)/Cu^(δ+)interfaces to undergo reduction to Cu^(0)during the CO_(2)RR process,leading to a decline in catalytic ***,it is crucial to establish durable Cu^(0)/Cu^(δ+)interfaces to enhance the conversion of CO_(2)to C_(2+)*** this work,an iodine modification strategy is proposed to prepare a stable Cu@CuI composite catalyst with well-maintained Cu^(0)/Cu^(δ+)interfaces through a one-step redox reaction between iodine and *** optimized Cu@CuI-3composite catalyst demonstrates an excellent performance in CO_(2)RR,achieving a Faradaic efficiency of 75.7%for C^(2+)products and a partial current density of 288 mA·cm^(-2)at-1.57 V_(RHE)in a flow *** techniques reveal that a numerous persistent Cu^(δ+)species exist on the surface of the Cu@CuI-X composite catalyst even after CO_(2)RR due to the presence of adsorbed iodine ions,which prevent complete reduction of Cu^(δ+)species to Cu^(0)owing to their high *** functional theory calculations further verify that adsorbed iodine ions on the surface of Cu@CuI-X serve as charge regulators by adjusting local charge density,thereby facilitating the formation of*CHO intermediates from CO_(2)and lowering the energy barriers associated with coupling the*CHO and*CO intermediates during CO_(2)***,this phenomenon enhances the selectivity toward C_(2+)products during electrocatalytic CO_(2)reduction.

关键词： CO_(2)electroreduction Cu^(0)/Cu^(δ+)interfaces Multicarbon products

Crebanine inhibits voltage-dependent Na～+ current in guinea-pig ventricular myocytes

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Chinese Journal of Natural Medicines 2014年第1期12卷 20-23页

作者： HE Xiao-Shan LIN Qing MA Yun-Shu YU ze-pu Yunnan University of Traditional Chinese Medicine

AIM: To study the effects of crebanine on voltage-gated Na+ channels in cardiac tissues. METHODS: Single ventricular myocytes were enzymatically dissociated from adult guinea-pig heart. Voltage-dependent Na+ current was recorded using the whole cell voltage-clamp technique. RESULTS: Crebanine reversibly inhibited Na+ current with an IC50 value of 0.283 mmol?L-1(95% confidence range: 0.248-0.318 mmol?L-1). Crebanine at 0.262 mmol?L-1 caused a negative shift(about 12 mV) in the voltage-dependence of steady-state inactivation of Na+ current, and retarded its recovery from inactivation, but did not affect its activation curve. CONCLUSION: In addition to blocking other voltage-gated ion channels, crebanine blocked Na+ channels in guinea-pig ventricular myocytes. Crebanine acted as an inactivation stabilizer of Na+ channels in cardiac tissues.

关键词： Arrhythmia Sodium channels Crebanine Myocardium Patch-clamp techniques