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Comparison of α particle detectors based on single-crystal diamond films grown in two types of gas atmospheres by microwave plasma-assisted chemical vapor deposition

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International Journal of Minerals,Metallurgy and Materials 2020年第5期27卷 703-712页

作者： Yan-zhao guo Jin-long liu Jiang-wei liu Yu-ting Zheng Yun Zhao Xiao-lu Yuan Zi-hao guo li-fu Hei liang-xian Chen Jun-jun Wei Jian-peng Xing Cheng-ming li Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Optical and Electronic Materials Unit National Institute for Materials Science(NIMSIbaraki 305-0044Japan Key Laboratory of Microelectronic Device and Integration Technology Institute of Microelectronics of the Chinese Academy of SciencesBeijing 100029China

Chemical vapor deposition(CVD)-grown diamond films have been developed as irradiation-resistant materials to replace or upgrade current detectors for use in extreme radiation environments. However, their sensitivity in practical applications has been inhibited by space charge stability issues caused by defects and impurities in pure diamond crystal materials. In this study, two high-quality CVD-grown single-crystal diamond(SCD) detectors with low content of nitrogen impurities were fabricated and characterized. The intrinsic properties of the SCD samples were characterized using Raman spectroscopy, stereomicroscopy, and X-ray diffraction with the rocking curve mode, cathode luminescence(CL), and infrared and ultraviolet-visible-near infrared spectroscopies. After packaging the detectors, the dark current and energy resolution under α particle irradiation were investigated. Dark currents of less than 5 pA at 100 V were obtained after annealing the electrodes, which is comparable with the optimal value previously reported. The detector that uses a diamond film with higher nitrogen content showed poor energy resolution, whereas the detector with more dislocations showed poor charge collection efficiency(CCE). This demonstrates that the nitrogen content in diamond has a significant effect on the energy resolution of detectors, while the dislocations in diamond largely contribute to the poor CCE of detectors.

关键词： single-crystal diamond nitrogen impurity detector αparticle

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Effects of ultrahigh pressure extraction on yield and antioxidant activity of chlorogenic acid and cynaroside extracted from flower buds of Lonicera japonica

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Chinese Journal of Natural Medicines 2015年第6期13卷 445-453页

作者： HU Wen guo Ting JIANG Wen-Jun DONG Guang-li CHEN Da-Wei YANG Shi-lin li He-Ran College of Pharmacy Soochow University Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Department of Polymer Science and Engineering College of Chemistry Chemical Engineering and Materials Science Soochow University Guiding Long Da Honeysuckle Technology Co. Ltd.

The present study was designed to establish and optimize a new method for extracting chlorogenic acid and cynaroside from Lonicera japonica Thunb. through orthogonal experimental designl. A new ultrahigh pressure extraction （UPE） technology was applied to extract chlorogenic acid and cynaroside from L. japonica. The influential factors, including solvent type, ethanol concentration, extraction pressure, time, and temperature, and the solid/liquid ratio, have been studied to optimize the extraction process, The optimal conditions for the UPE were developed by quantitative analysis of the extraction products by HPLC-DAD in comparison with standard samples. In addition, the microstructures of the medicinal materials before and after extraction were studied by scanning electron microscopy （SEM）. Furthermore, the extraction efficiency of different extraction methods and the 2, 2-diphenyl-1-picrylhydrazyl （DPPH） radical scavenging activities of the extracts were investigated. The optimal conditions for extracting chlorogenic acid and cynaroside were as follows： ethanol concentration, 60%; extraction pressure, 400 MPa; extraction time, 2 rain; extraction temperature, 30 ℃; and the solid/liquid ratio, 1 ： 50. Under these conditions, the yields of chlorogenic acid and cynaroside were raised to 4.863% and 0.080%, respectively. Compared with other extraction methods, such as heat reflux extraction （HRE）, ultrasonic extraction （UE）, and Sohxlet extraction （SE）, the UPE method showed several advantages, including higher extraction yield, shorter extraction time, lower energy consumption, and higher purity of the extracts. This study could help better utilize L. japonica flower buds as a readily accessible source of natural antioxidants in food and pharmaceutical industries.

关键词： Lonicerajaponica Thunb. Ultrahigh pressure extraction Chlorogenic acid Cynaroside Antioxidant activity

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Fast determination of multi-mycotoxins in corn by dispersive solid-phase extraction coupled with ultra-performance liquid chromatography with tandem quadrupole time-of-flight mass spectrometry

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Journal of Integrative Agriculture 2016年第7期15卷 1656-1666页

作者： WANG Yan DONG Yan-jie li Zeng-mei DENG li-gang guo Chang-ying ZHANG Shu-qiu li Da-peng ZHAO Shan-cang Institute of Agricultural Quality Standards and Testing Technology Research Shandong Academy of Agricultural SciencesJinan 250100P.R.China Academy of Food Science and Engineering Shandong Agricultural UniversityTai'an 271018P.R.China

A fast analytical method for the simultaneous determination of 9 mycotoxins, including alfatoxins （B1, B2, G1, and G2）, fumonisins （B1, B2 and B3）, zearalenone, and deoxynivalenol in corn using dispersive solid-phase extraction method and ultra-performance liquid chromatography coupled to tandem quadrupole time-of-lfight mass spectrometry （UPLC-Q-TOF-MS） was developed and validated. Samples were extracted with acetonitrile-water （84：16, v：v, containing 1% acetic acid） using ultrasonic extraction. The extracts were puriifed with a dispersive SPE method using C18 as a cleaning agent. The ifnal clear extracts were dried by nitrogen blowing and subsequently redissolved in methanol-water （5：5, v：v）. The samples were then analyzed by UPLC-Q-TOF-MS with 0.1% formic acid in ammonium acetate-methanol as mobile phase. The mean recoveries were ranged from 68.0 to 120.0%, and the relative standard deviation （RSD） ranged from 0.18 to 6.29%. limits of detections ranged from 0.05 to 50 μg kg？1, and limits of quantiifcation ranged from 0.1 to 200 μg kg？1, which were below the legal limits set by the European Union for the legislated mycotoxins. The developed method was applied to 130 corn samples. Among the mycotoxins studied, alfatoxins B1 and fumonisins B1, B2 and B3 were the most predominant mycotoxins, and their concentrations were 0–593.12, 0–2.01×104, 0–6.94×103 and 0–3.05×103 μg kg–1, respectively.

关键词： C18 corn mycotoxins dispersive solid-phase extraction

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ZrB2-SiC spiral fibers prepared by combining liquid rope effect with non-solvent-induced phase separation method:A promising toughening material for ultra-high temperature ceramics

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Journal of Advanced Ceramics 2023年第1期12卷 132-144页

作者： Ruiji ZHANG Fangwei guo Xing ZHANG Wenchen ZHANG li HU Desheng liU Xiaofeng ZHAO Xin WANG Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory of Spacecraft Mechanism Shanghai 201108China Shanghai Institute of Aerospace System Engineering Shanghai 201108China Konca Solar Cell Co. Ltd.Wuxi 214174China

Spiral fibers were considered to be an ideal toughening phase of ultra-high torsional release *** this work,ZrB_(2)(Z)-20 vol%SiC(S)spiral fiber(ZS_(sf))with controllable structure was prepared by a combination approach of liquid rope effect and non-solvent-induced phase *** depended on the kinematic viscosity(η),dropping height(H),and flow rate(Q),the geometric parameters of ZS_(sf) involving filament diameter(d)and coil diameter(D)were followed the relationship of d≈0.516×10^(-3) Q^(1/2)H^(−1/4) and D≈0.25×10^(-3)(Q/H)^(1/3),respectively,within the optimizedηof 10-15 Pa·*** different microstructures of ZS_(sf) were achieved by adjusting the polymer/solvent/non-solvent system assisted with phase diagram calculation,including dense,hollow,and hierarchical pore *** ZrB_(2)-SiC with 1 wt%ZS_(sf) composites prepared by hot isostatic pressing(HIP)exhibited a~30%increase in fracture toughness(KIC,4.41 MPa·m^(1/2))compared with the ZrB_(2)-SiC composite,where the microscopic fracture toughness of the ZS_(sf) was~80%higher than that of the *** fibers with a~10 nm in-situ-synthesized graphite phase amongst grain boundaries of ZrB_(2) and SiC changed the fracture mode,and promoted the crack deflection and pull-out adjacent the interface of matrix and the fiber.

关键词： ultra-high-temperature ceramics(UHTCs) spiral fibers liquid rope effect structure control fracture toughness

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Effects of Temperature and Alloying Elements on γ Phase Fraction of Grain-oriented Silicon Steel

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Journal of Iron and Steel Research International 2016年第6期23卷 573-579页

作者： Bing FU Hai-jun WANG Jian-xin YAN li XIANG Sheng-tao QIU guo-guang CHENG National Engineering Research Center of Continuous Casting Technology China Iron and Steel Research Institute Group School of Metallurgical and Ecological Engineering University of Science and Technology Beijing State Key Laboratory of Advanced Steel Processes and Products Central Iron and Steel Research Institute Valin LY Steel Co. Ltd.

The effects of temperature and alloying elements on γ phase fraction of grain-oriented silicon steel,which contained 2.97-3.42mass% Si and 0.028-0.058mass% C,were studied by microstructure observation and ***,the quantitative relationships of temperature as well as C,Si,and Mn contents to γ phase fraction were obtained by numerical *** experimental results show that γ phase fraction firstly increases with increasing temperature,reaches a maximum and then decreases in the temperature range of 900-1 250 ℃.The temperature corresponding to the maximum γ phase fraction is about 1 150-1 200℃.Meanwhile,the γ phase fractions in steels at the same temperature have some differences because of different contents of various alloying *** verification results show that the values of γ phase fractions to C,Si,and Mn contents at the specific temperatures,which were obtained by multiple linear regression method,agree well with the measured *** addition,the values of γ phase fractions to C,Si,and Mn contents in the temperature range of 900-1 250℃,which were obtained by binomial regression method,agree with the measured values when the contents of Mn and soluble Al are not more than 0.320mass% and 0.034mass%,*** obtained equations can carry out the approximate prediction of γ phase fractions of grain-oriented silicon steels during the hot rolling process.

关键词： fitting Grain steels approximate alloying carry agree reaches contained utilizing

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Gas sensing selectivity of oxygen-regulated SnO2 films with different microstructure and texture

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Journal of Materials Science & Technology 2019年第10期35卷 2232-2237页

作者： Ruiwu li Yanwen Zhou Maolin Sun Zhen Gong Yuanyuan guo Xitao Yin Fayu Wu Wutong Ding School of Material Science and Metallurgy University of Science and Technology LiaoningAnshan114051China State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050China

The selectivity of gas sensing materials is increasingly important for their applications. The oxygenregulated SnO2 films with(110) and(101) preferred orientation were obtained through magnetron sputtering, followed by annealing treatment. Their micro-structure, surface morphology and gas response were investigated by advanced structural characterization and property measurement. The results showed that the as-prepared(110)-oriented SnO2 film was oxygen-rich and had more adsorption sites while the as-prepared(101)-oriented SnO2 film was oxygen-poor and more sensitive to de-oxidation.H2 gas sensitivity, response speed, selectivity between H2 and CO of the(110)-orientated SnO2 film was superior to that of the(101)-orientated SnO2 film. After treated at high temperature and high vacuum,the reduction of gas-sensing properties of the annealed(110) SnO2 film was much more than that of the annealed(101) SnO2 film. The lattice oxygen was responsible for the difference in gas-sensing response between(110) and(101)-oriented SnO2 films under oxygen regulation. This work indicated the gassensing selectivity of the different crystal planes in SnO2 film, providing a significant reference for design and extension of the related materials.

关键词： Gas sensor SnO2 Oxygen regulation Preferred orientation H2 selectivity

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Overlooked risk of microplastics from municipal solid waste-storage site

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Frontiers of Environmental Science & Engineering 2024年第10期18卷 103-114页

作者： Ying Hu Shuli guo Dongsheng Shen Jiali Shentu li Lu Shengqi Qi Min Zhu Yuyang Long Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling Zhejiang Engineering Research Center of Non-ferrous Metal Waste RecyclingSchool of Environmental Science and EngineeringZhejiang Gongshang UniversityHangzhou 310012China

Municipal solid waste(MSW)storage sites are potential and overlooked contributors to microplastic(MP)***,the distribution and dispersion characteristics of MPs at MSW storage sites were investigated through modeling,sampling analysis,and prediction *** results indicated a notable adsorption phenomenon of MPs on smooth surfaces within such sites,achieving high saturation levels and making MPs prone to re-release by airflow *** analysis revealed that the MP concentrations on these surfaces varied from 4.48×10^(5) to 1.90×10^(6) n/m^(2) and that MPs predominantly accumulated in the corner ***,MP accumulation on wall surfaces can be reduced by 76.4%using washing *** majority of MPs were under 50μm in size and were primarily in fragment *** activities such as ventilation and waste handling were identified to amplify the airborne spread of *** atmospheric concentrations of MPs peaked seasonally,with concentrations of 28.25 n/m^(3) in summer and 3.90 n/m^(3) in winter,and the spatial dispersion ranged from 14.98 to 124.08 km^(2) per *** study highlights that MSW storage sites are substantial yet overlooked sources of MP pollution,where wall surfaces play a critical role in MP adsorption and *** implementation of robust management and cleaning protocols is essential to mitigate the environmental footprint of MPs emanating from these *** study also provides a typical case for the precise prevention and control of MPs in the environment.

关键词： Municipal solid waste storage sites Microplastic Adsorption Dispersion Emerging pollution

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Cooperation of metal-organic coordination complex separator and wide-temperature-range electrolyte enables safe and high-performance lithium batteries

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Journal of Energy Chemistry 2024年第12期99卷 692-702页

作者： You Gao Qing-Song liu guo-Rui Zhu Gang Wu Xiu-li Wang Yu-Zhong Wang The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu 610064SichuanChina

With the increase of people’s demand,it is extremely desired for developing high-safety,widetemperature-range and high-energy-density lithium batteries,but huge challenges are remained due to shrinkage and combustion of commonly used polyolefin separators at high temperatures,as well as narrow usable temperature range and high flammability of conventionally commercialized liquid *** this work,we report a multifunctional separator mainly consisting of Zn^(2+)-phytate coordination complex nanoparticles and bacterial cellulose nanofibers,named the BZP separator,which possesses high porosity,excellent thermotolerance,good flame retardancy,abilities of anion binding and Ni^(2+)*** cooperating with the fluoride-free wide-temperature-range electrolyte,li//liFePO_(4) cells not only deliver discharge capacities of 110.39 mA h g^(-1)and 113.25 mA h g^(-1)after 2200 cycles (2 C) and1600 cycles (5 C) at 25℃,with capacity retentions of 76.59%and 86.09%,respectively,but also exhibit excellent cycling performance at 80℃ and-40℃.Significantly,the li//NCM811 cell with a loading of7.8 mg cm^(-2)delivers a discharge capacity of 146.64 mA h g^(-1)after 200 cycles at 0.5 C,with a capacity retention of 89.03%.In addition,pouch cells can work at 120℃ and have low flammability.

关键词： Metal-organic coordination complex Separator Electrolyte Thermal and fire safety lithium batteries

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High efficiency and broad bandwidth terahertz vortex beam generation based on ultra-thin transmission Pancharatnam-Berry metasurfaces

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Chinese Physics B 2021年第5期30卷 667-672页

作者： Wenyu li guozhong Zhao Tianhua Meng Ran Sun Jiaoyan guo Department of Physics Capital Normal UniversityBeijing Key Laboratory for THz Spectroscopy and ImagingKey Laboratory of THz OptoelectronicsMinistry of EducationBeijing 100048China Institute of Solid State Physics Shanxi Datong UniversityDatong 037009China

The terahertz(THz)vortex beam generators are designed and theoretically investigated based on single-layer ultra-thin transmission *** phase changes of metasurfaces are obtained by utilizing Pancharatnam-Berry phase elements,which possess different rotation angles and are arranged on two concentric rings centered on the *** circularly polarized incident THz beam could be turned into a cross-polarization transmission wave,and the orbital angular momentum(OAM)varies in value by *** l values change from±1 to±5,and the maximal cross-polarization conversion efficiency that could be achieved is 23%,which nearly reaches the theoretical limit of a single-layer *** frequency range of the designed vortex generator is from 1.2 THz to 1.9 THz,and the generated THz vortex beam could keep a high fidelity in the operating *** propagation behavior of the emerged THz vortex beam is analyzed in *** work offers a novel way of designing ultra-thin and single-layer vortex beam generators,which have low process complexity,high conversion efficiency and broad bandwidth.

关键词： metasurface terahertz vortex beam Pancharatnam-Berry phase element conversion efficiency

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CeO_2-ZrO_2-La_2O_3-Al_2O_3 composite oxide and its supported palladium catalyst for the treatment of exhaust of natural gas engined vehicles

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Journal of Natural Gas Chemistry 2009年第2期18卷 139-144页

作者： Xiaoyu Zhang Enyan,Long Yile li Jiaxiu guo lijuan Zhang Maochu Gong Minghua Wang Yaoqiang Chen Key Laboratory of Green Chemistry ＆ Technology of the Ministry of Education College of Chemistry Sichuan University Chengdu 610064 Sichuan China College of Architecture and Environment Sichuan University Chengdu 610064 Sichuan China State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Liaoning China Sichuan Tianyi Science ＆ Technology Co. Ltd. Chengdu 610225 Sichuan China

Composite supports CeO2-ZrO2-Al2O3（CZA） and CeO2-ZrO2-Al2O3-La2O3（CZALa） were prepared by co-precipitation method. Palladium catalysts were prepared by impregnation and their purification ability for CH4, CO and NOx in the mixture gas simulated the exhaust from natural gas vehicles （NGVs） operated under stoichiometric condition was investigated. The effect of La2O3 on the physicochemical properties of supports and catalysts was characterized by various techniques. The characterizations with X-ray diffraction （XRD） and Raman spectroscopy revealed that the doping of La2O3 restrained effectively the sintering of crystallite particles, maintained the crystallite particles in nanoscale and stabilized the crystal phase after calcination at 1000 ℃. The results of N2-adsorption, H2-temperatnre-programmed reduction （H2-TPR） and oxygen storage capacity （OSC） measurements indicated that La2O3 improved the textural properties, reducibility and OSC of composite supports. Activity testing results showed that the catalysts exhibit excellent activities for the simultaneous removal of methane, CO and NOx in the simulated exhaust gas. The catalysts supported on CZALa showed remarkable thermal stability and catalytic activity for the three pollutants, especially for NOx. The prepared palladium catalysts have high ability to remove NOx, CH4 and CO, and they can be used as excellent catalysts for the purification of exhaust from NGVs operated under stoichiometric condition. The catalysts reported in this work also have significant potential in industrial application because of their high performance and low cost.

关键词： Pd catalysts natural gas vehicles exhaust methane oxidation NOx conversion CeO2-ZrO2-Al2O3 La2O3

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