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Determination of Inorganic Anions and Melamine in Fertilizers by Ion Chromatography

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Asian Agricultural Research 2021年第8期13卷 38-42页

作者： Chen LIANG Miaomiao ZHANG Xiaojiao WANG Yunli YAN pengfei fu Qingdao Shenghan Chromatograph Technology Co. Ltd. Qingdao 266101 China

A chromatographic analysis method for determining inorganic anions and melamine in fertilizers was established using ion chromatography(IC).The fertilizer samples were extracted by ultrasonic method with 7 g/L trichloroacetic acid solution and centrifuged.The supernatant is purified by a solid phase extraction column.Then,the anions in the solution were purified using SH-AP-1(250 mm×4.0 mm)as a separation column,and measured by a suppressed conductivity detector;the melamine in the solution was separated using SH-CC-4(200 mm×4.0 mm)as a separation column and detected by a UV detector.The results show that the mass concentration of anions had a linear relationship with its peak area within a certain range,the linear correlation coefficient r of the standard curve was greater than 0.999,the recovery rate of spiked samples was 93.4%-104.4%,and the relative standard deviation(RSD)of the measured value(n=6)was less than 4%.Thus,this method is widely suitable for detection of anions and cations in a variety of fertilizer samples.

关键词： Ion chromatography(IC) Fertilizer Anion Melamine

Soil bacterial and fungal communities resilience to long-term nitrogen addition in subtropical forests in China

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Journal of Forestry Research 2024年第2期35卷 95-108页

作者： Xinlei fu Yunze Dai Jun Cui pengfei Deng Wei Fan Xiaoniu Xu School of Forestry and Landscape Architecture Anhui Agricultural UniversityHefei 230036AnhuiPeople’s Republic of China Suzhou Polytechnic Institute of Agriculture Suzhou 215008JiangsuPeople’s Republic of China College of Life and Environment Sciences Huangshan UniversityHuangshan 245041AnhuiPeople’s Republic of China

Atmospheric nitrogen(N)deposition is predicted to increase,especially in the subtropics.However,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have not been clarified.A long-term nutrient addition experiment was conducted in a subtropical evergreen old-growth forest in China.The four treatments were:control,low N(50 kg N ha^(-1)a^(-1)),high N(100 kg N ha^(-1)a^(-1)),and combined N and phosphorus(P)(100 kg N ha^(-1)a^(-1)+50 kg P ha^(-1)a^(-1)).Metagenomic sequencing characterized diversity and composition of soil microbial communities and used to construct bacterial/fungal co-occurrence networks.Nutrient-treated soils were more acidic and had higher levels of dissolved organic carbon than controls.There were no significant differences in microbial diversity and community composition across treatments.The addition of nutrients increased the abundance of copiotrophic bacteria and potentially beneficial microorganisms(e.g.,Gemmatimonadetes,Chaetomium,and Aureobasidium).Low N addition increased microbiome network connectivity.Three rare fungi were identified as module hubs under nutrient addition,indicating that low abundance fungi were more sensitive to increased nutrients.The results indicate that the overall composition of microbial communities was stable but not static to long-term N addition.Our findings provide new insights that can aid predictions of the response of soil microbial communities to long-term N addition.

关键词： Long-term nitrogen addition Old-growth subtropical forest Metagenomics Beneficial microorganisms Co-occurrence network

关节镜下自体复合补片移植联合肱二头肌长头腱重建上关节囊治疗巨大不可修复肩袖撕裂的疗效

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中华创伤杂志 2024年第3期40卷 236-242页

作者：冀云聪许健康运康毕文智马炜杨东强崔红林付鹏飞刘一军田进翔郭标蚌埠医科大学附属阜阳医院(阜阳市人民医院)骨科运动医学与关节镜病区阜阳236000

目的探讨关节镜下自体复合补片移植联合肱二头肌长头腱重建上关节囊治疗巨大不可修复肩袖撕裂(IMRCT)的疗效。方法采用回顾性病例系列研究分析2020年5月至2022年6月蚌埠医科大学附属阜阳医院(阜阳市人民医院)收治的11例IMRCT患者的临床... 详细信息

目的探讨关节镜下自体复合补片移植联合肱二头肌长头腱重建上关节囊治疗巨大不可修复肩袖撕裂(IMRCT)的疗效。方法采用回顾性病例系列研究分析2020年5月至2022年6月蚌埠医科大学附属阜阳医院(阜阳市人民医院)收治的11例IMRCT患者的临床资料,其中男7例,女4例;年龄54~74岁[(62.6±7.3)岁]。患者均采用关节镜下自体复合补片移植联合肱二头肌长头腱重建上关节囊治疗。比较术前、术后6个月及末次随访时视觉模拟评分(VAS)、肩肱距离(AHD)、Constant⁃Murley评分、美国加州大学洛杉矶分校(UCLA)功能评分和肩关节主动活动度。末次随访时行肩关节MRI评估重建上肩关节囊和肱二头肌长头腱的完整性。观察术后并发症发生情况。结果患者均获随访13~39个月[16(13,36)个月]。术后6个月,肩关节VAS、AHD、Constant⁃Murley评分和UCLA功能评分分别为2(2,3)分、(9.1±1.1)mm、(56.1±5.4)分、(19.7±2.8)分,均较术前改善[6(5,7)分、(5.1±1.2)mm、(37.9±2.2)分、(11.8±1.2)分](P0.05);Constant⁃Murley评分、UCLA功能评分均较术后6个月进一步改善(P0.05)。末次随访时,MRI显示10例患者重建上关节囊和肱二头肌长头腱完整。术后1年1例出现大结节吸收,1例冈上肌肌腱部分撕裂。结论采用关节镜下自体复合补片移植联合肱二头肌长头腱重建上关节囊治疗IMRCT,可缓解肩关节疼痛、减少肱骨头上移、改善肩关节功能及活动度、减少并发症。

关键词：肩损伤关节镜检查腱固定术关节囊阔筋膜

Microstructures and fatigue properties of electron beam welds with beam oscillation for heavy section TC4-DT alloy

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Chinese Journal of Aeronautics 2014年第4期27卷 1015-1021页

作者： fu pengfei Mao Zhiyong Zuo Congjin Wang Yajun Wang Chunming College of Materials Science and Engineering Huazhong University of Science and Technology Science and Technology on Power Beam Processes Laboratory Beijing Aeronautical Manufacturing Technology Research Institute Institute of Mechanical Engineering and Automation Beihang University

With the development of the manufacturing technology, electron beam welding（EBW） is capable of producing titanium alloy large parts in aero fields. To increase the applications and improve the properties, EBW with beam oscillation was investigated on TC4-DT alloy with50 mm thickness. We detected the welding samples by X-ray NDT, observed the microstructures of the welds, and tested the fatigue properties of the joints. The results showed that EBW with beam oscillation improved the weld morphology as well as welding quality, and the microstructure homogeneity of the welds and HAZ along the weld penetration were also improved. The fatigue properties of the joints with beam oscillation were more excellent than those of conventional EBW, even equal to those of the base metal under high stresses. The influences of the processing and the microstructure on the properties with beam oscillation were discussed.

关键词： Beam oscillation Electron beam welding（EBW） Fatigue Microstructure Titanium alloy

Simultaneous acceleration of sulfur reduction and oxidation on bifunctional electrocatalytic electrodes for quasi-solid-state Zn–S batteries

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Science China Chemistry 2024年第5期67卷 1531-1538页

作者： Mingli Wang Hong Zhang Tianhang Ding Fangjun Wu Lin fu Bin Song pengfei Cao Ke Lu Institutes of Physical Science and Information Technology School of Materials Science and EngineeringKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei 230601China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China Institute of functional Nano&Soft Materials(fuNSOM) Soochow UniversitySuzhou 215123China State Key Lab of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China

The incomplete sulfur reduction and high ZnS re-oxidation energy barrier along with severe side reactions during the battery cycling compromise the practical application of Zn–S electrochemistry. Herein, a bifunctional electrocatalytic sulfur matrix that simultaneously accelerates the sulfur reduction and ZnS oxidation is proposed to realize a highly-efficient Zn–S cell. It is revealed that the N-heteroatom hotspots are more favorable for facilitating the conversion of S to ZnS while the CoO nanocrystal substantially lowers the ZnS activation energy barrier thereby suppressing the formation of disproportionation species(e.g.,SO_(4)^(2-)) and accumulation of inactive ZnS. Accordingly, the Co O anchored on the N-doped carbon-supported sulfur cathode delivers a high Zn^(2+)storage capacity of 1,172 m Ahg^(-1)and outstanding cycling stability with a capacity retention of 71.6% after500 cycles with a high average Coulombic efficiency of 97.8%. Simultaneously, the stable cycling of solid-state Zn–S pouch cells with an energy density of 585 Whkg^(-1)sulfuris also demonstrated. Moreover, the postmortem analysis reveals that the degradation of Zn–S cells is mainly attributed to the limited reversibility of Zn anodes rather than the ZnS decomposition and/or accumulation. The approach to the bidirectional catalysis manipulated the sulfur redox provides a new perspective to realize the theoretical potentials of Zn–S cells.

关键词： Zn–S battery bifunctional catalysts solid-state battery sulfur redox degradation mechanism

Research on modeling of heat source for electron beam welding fusion-solidification zone

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Chinese Journal of Aeronautics 2013年第1期26卷 217-223页

作者： Wang Yajun fu pengfei Guan Yongjun Lu Zhijun Wei Yintao School of Mechanical Engineering and Automation Beihang University Science and Technology on Power Beam Processes Laboratory Beijing Aeronautical Manufacturing Technology Research Institute State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences State Key Laboratory of Automotive Safety and Energy Department of Automotive Engineering Tsinghua University

In this paper, the common heat source model of point and linear heat source in the numerical simulation of electron beam welding （EBW） were summarized and introduced. The combined point-linear heat source model was brought forward and to simulate the welding temperature fields of EBW and predicting the weld shape. The model parameters were put forward and regulated in the combined model, which included the ratio of point heat source to linear heat source Qpr and the distribution of linear heat source Lr. Based on the combined model, the welding temperature fields of EBW were investigated. The results show that the predicted weld shapes are conformable to those of the actual, the temperature fields are reasonable and correct by simulating with combined point-linear heat source model and the typical weld shapes are gained.

关键词： Electron beam welding （EBW） fusion-solidification zone Heat source model Temperature fields Weld shape

Effects of donor cells on in vitro development of cloned bovine embryos

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Journal of Genetics and Genomics 2008年第5期35卷 273-278页

作者： Jing fu pengfei Guan Leiwen Zhao Hua Li Shuzhen Huang Fanyi Zeng Yitao Zeng Shanghai Institute of Medical Genetics Shanghai Children＇s Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200040 China

The donor cells from different individuals and with different foreign genes introduced were investigated to determine their effects on the efficiency of somatic cell nuclear transfer （SCNT）. The bovine ear fibroblast from different individuals was isolated, cultured, and then transfected with foreign genes to establish the stable cell lines, which were used as donor cells for nuclear transfer. The oocytes were obtained through ovum pick up operation. After in vitro maturation, the M II phase oocytes were selected as receptors for nuclear transfer. The reconstructed embryos were cultured in vitro and observed at 2 h, 48 h, and 7 days after transfer to assess the rate of fusion using cleaved and blastocyst as the parameters of SCNT efficiency. The donor cells from different individuals （04036, 06081, 06088, and 06129） had no obvious effect on the fusion and cleaved rate, whereas there was significant difference in the blastocyst rate （P〈0.05）, and the rate was 62.3%, 37.0%, 35.1%, and 15.6%, respectively. There was no significant difference among the rate of fusion, cleaved and blastocyst in donor cells with different foreign genes （P〉0.05）. It was concluded that the genetic background of the donor cells could affect the efficiency of SCNT, while the introduction of foreign genes into the donor cells had no obvious effect on the efficiency. This study provides useful information for the SCNT and would benefit in promoting the efficiency.

关键词： donor cell bovine somatic nuclear transfer transgene

Paleoclimatic application of spectral parameters to the eolian red clay of the Jianzha Basin,northeastern margin of the Tibetan Plateau

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Science China Earth Sciences 2024年第6期67卷 1952-1966页

作者： Chaofeng fu Ju’e TIAN Xinwen XU Yougui SONG Jun ZUO Feng WANG Lin CHEN pengfei LI Xiaoke QIANG The School of Earth Science and Resources Chang’an UniversityXi’an 710054China State Key Laboratory of Loess and Quaternary Geology Institute of Earth and EnvironmentCASXi’an 710061China College of Urban and Environmental Science Northwest UniversityXi’an 710069China CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China

Reflectance spectroscopy is rapid,inexpensive,and non-destructive and can provide important information about the mineralogy of rocks and sediments.We measured the reflectance spectroscopy of Miocene red clay deposits on the northeastern margin of the Tibetan Plateau,with the aim of developing a rapid methodology for detecting paleoclimatic changes.We obtained visible/near-infrared(VNIR)and short-wave infrared(SWIR)spectroscopy data from the red clay in the Jianzha Basin,and analyzed their relationship with independent paleoclimatic records,including mineral contents and environmental magnetic parameters.The results show that the VNIR parameters,including D500,D900,R500,and R900(where D and R represent the depth and reflectance of the absorption peaks around 500 and 900 nm,respectively)are temperature-sensitive and correlated with the magnetic susceptibility,frequency-dependent magnetic susceptibility,and the marine δ^(18)O record.The results of frequency-domain analysis of the VNIR parameters show that they reflect climate change on orbital timescales.SWIR parameters,such as AS1400,D1400/D1900 and D1900(where AS represents the asymmetry of the absorption peaks around1400 nm),are correlated with the illite and montmorillonite content,and they are sensitive to the weathering intensity.The spectral parameters of the eolian red clay in the Jianzha Basin reflect regional climatic changes caused by the uplift of the Tibetan Plateau at~8.5 Ma and global climatic cooling at~7.2 Ma,and thus they are applicable as both regional and global paleoenvironmental indicators.

关键词： Visible/near-infrared spectroscopy Short-wave infrared spectroscopy Paleoclimatic indicators Red clay Tibetan Plateau

游客生态系统文化服务价值感知的生态消费行为选择意愿效应

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华中师范大学学报（自然科学版） 2022年第5期56卷 882-890页

作者：郭晓彬姚娟付鹏飞新疆农业大学经济管理学院乌鲁木齐830052

生态系统文化服务和人类的价值观与行为紧密相连,是连接自然生态与人类行为的关键纽带,对我国生态文明建设具有重要意义.该文以新疆天山世界自然遗产地巴音布鲁克为研究区,探讨游客对不同维度生态系统文化服务价值的感知水平,并利用结... 详细信息

生态系统文化服务和人类的价值观与行为紧密相连,是连接自然生态与人类行为的关键纽带,对我国生态文明建设具有重要意义.该文以新疆天山世界自然遗产地巴音布鲁克为研究区,探讨游客对不同维度生态系统文化服务价值的感知水平,并利用结构方程模型探索影响游客生态消费行为选择意愿的主要因素和影响机理、影响路径.研究结果表明:研究区生态系统文化服务价值包括地方感、教育价值和休憩价值,游客感知水平从高到低排序依次为休憩价值、教育价值、地方感;游客生态消费行为选择意愿的排序为废弃物排放>餐食>购物>住宿;地方感和休憩价值的感知水平对游客生态消费行为选择意愿有着正向影响,但教育价值的感知水平与生态消费行为选择意愿之间的关系尚不明确.根据研究结论,提出提高游客对生态系统文化服务价值的感知水平,进而增强其生态消费行为选择意愿的政策建议.

关键词：生态系统文化服务地方感教育价值休憩价值消费意愿