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Impact of agricultural residual plastic film on the growth and yield of drip-irrigated cotton in arid region of Xinjiang, China

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International Journal of Agricultural and Biological Engineering 2020年第1期13卷 160-169页

作者： Can Hu Xufeng Wang Shiguo Wang Bing Lu Wensong guo Chaoji Liu xiuying Tang College of Engineering China Agricultural UniversityBeijing 100083China College of Mechanical and Electrical Engineering Tarim UniversityAlar 843300XinjiangChina Xinjiang Academy of Agricultural and Reclamation Science Mechanical Equipment Research Institute Shihezi 832000China

Long-term and widespread use of plastic mulching has led to the accumulation of residual plastic film(RPF)in farmland soils of Xinjiang,***,there is no specific quantitative basis for RPF pollution or a clear understanding of the influence of residual film on crop *** aim of this study was to investigate the effect of RPF on the growth of cotton,an important cash crop of *** on the field conditions and previous reports,various amount of residual film was applied in 0-30 cm soil *** growth index including emergence rate,dry matter,and yield of cotton was examined at different growth stages under different soil residual film *** demonstrated a significant effect of RPF on soil moisture distribution and *** residues had a significant effect on cotton growth at levels above 200 kg/hm2,and the yield decreased as the RPF amount *** on these findings,200 kg/hm2 was suggested as a threshold level to determine the effects of RPF on *** study provided a basis to rate RPF pollution in farmland soils and help understand the impact of pollution on crop productivity.

关键词： residual plastic film plastic film pollution soil pollution pollution control cotton production management

Enhanced mechanical properties and degradation rate of Mg-Ni-Y alloy by introducing LPSO phase for degradable fracturing ball applications

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Journal of Magnesium and Alloys 2020年第1期8卷 127-133页

作者： Jingfeng Wang Shiqing Gao xiuying Liu Xing Peng Kui Wang Shijie Liu Weiyan Jiang Shengfeng guo Fusheng Pan National Engineering Research Center for Magnesium Alloys College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Faculty of Materials and Energy Southwest UniversityChongqing 400715China

In this work,as-cast Mg-Ni-Y alloys were proposed to develop a feasible material for fracturing balls,and their mechanical performance and corrosion behavior were systematically *** period stacking order(LPSO)phase was firstly introduced to improve both the mechanical properties and degradation rate of magnesium *** the increase of LPSO phase,the compressive strength was improved significantly,while the elongation of the alloys decreased owing to the relatively brittle nature of LPSO *** to the higher corrosion potential of LPSO phase,the LPSO phase can accelerate the corrosion process by providing more ***,the LPSO phase would serve as the corrosion barrier between the corrosion medium and the matrix when the contents of LPSO phase are too high in Mg92.5Ni3Y4.5 and Mg87.5Ni5Y7.5 ***-cast Mg97.5Ni1Y1.5 alloy with satisfactory mechanical properties and rapid degradation rate was successfully developed,exhibiting a high degradation rate of 6675 mm/a(93℃)in 3 wt.%KCl solution and a favorable ultimate compressive strength of 410 *** degradation rate of Mg97.5Ni1Y1.5 alloy is 2-5 times of the current commercial magnesium alloy fracturing materials.

关键词： Mg-Ni-Y magnesium alloys Fracturing ball LPSO phase Degradation rate Mechanical properties

Three-layer phosphorene-metal interfaces

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Nano Research 2018年第2期11卷 707-721页

作者： xiuying Zhang Yuanyuan Pan Meng Ye Ruge Quhe Yangyang Wang Ying guo Han Zhang Yang Dan Zhigang Song Jingzhen Li Jinbo Yang Wanlin guo Jing Lu State Key Laboratory for Mesoscopic Physics and Department of Physics Peking University Beijing China State Key Laboratory of Information Photonics and Optical Communications and School of Science Beijing University of Posts and Telecommunications Beijing China Nanophotonics and Optoelectronics Research Center Qian Xuesen Laboratory of Space Technology China Academy of Space Technology Beijing China School of Physics and Telecommunication Engineering Shaanxi Sci-Tech University Hanzhong China Collaborative Innovation Center of Quantum Matter Beijing China Key Laboratory for Intelligent Nano Materials and Devices of the Ministry of Education Nanjing University of Aeronautics and Astronautics Nanjing China

Phosphorene has attracted much attention recently as an alternative channel material in nanoscale electronic and optoelectronic devices due to its high carrier mobility and tunable direct bandgap. Compared with monolayer （ML） phosphorene, few-layer （FL） phosphorene is easier to prepare, is more stable in experiments, and is expected to form a smaller Schottky barrier height （SBH） at the phosphorene-metal interface. Using ab initio electronic structure calculations and quantum transport simulations, we perform a systematic study of the interfacial properties of three-layer （3L） phosphorene field effect transistors （FETs） contacted with several common metals （A1, Ag, Au, Cu, Ti, Cr, Ni, and Pd） for the first time. The SBHs obtained in the vertical direction from projecting the band structures of the 3L phosphorene-metal systems to the left bilayer （2L） phosphorenes are comparable with those obtained in the lateral direction from the quantum transport simulations for 2L phosphorene FETs. The quantum transport simulations for the 3L phosphorene FETs show that 3L phosphorene forms n-type Schottky contacts with electron SBHs of 0.16 and 0.28 eV in the lateral direction, when Ag and Cu are used as electrodes, respectivel~ and p-type Schottky contacts with hole SBHs of 0.05, 0.11, 0.20, 0.30, 0.30, and 0.31 eV in the lateral direction when Cr, Pd, Ni, Ti, AI, and Au are used as electrodes, respectively. The calculated polarity and SBHs of the 3L phosphorene FETs are generally in agreement with the available experiments.

关键词： three-layer phosphorene interfacial properties Schottky barrier height density functional theorquantum transportsimulation

Distribution of microplastics in mulched soil in Xinjiang, China

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International Journal of Agricultural and Biological Engineering 2021年第2期14卷 196-204页

作者： Can Hu Bing Lu Wensong guo xiuying Tang Xufeng Wang Yinghao Xue Long Wang Xiaowei He College of Mechanical and Electrical Engineering Tarim UniversityAlar 843300XinjiangChina College of Engineering China Agricultural UniversityBeijing 100083China Rural Energy and Environment Agency Ministry of Agriculture and Rural AffairsBeijing 100125China

In order to study the distribution of soil microplastics in the plastic film mulched farmland,the fluidization-centrifugation secondary density flotation method was optimized and improved to obtain the *** main components of microplastics were analyzed by Fourier spectrometer,and the surface morphology,porosity,particle size and abundance distribution characteristics of microplastics were studied by electron *** results showed that plastic mulch is the main source of *** morphology mainly consists of fragments,fibers and *** size of debris microplastics was larger,with an average of 1.6300 mm,mainly distributed in the 0-300 mm cultivation layer while the size of particle micro plastic was smaller,with an average of 0.1400 *** width of fiber microplastic was 5-20μm,but the length could reach 0.2000-2.0000 mm,with an average particle size of 0.9200 *** and granular microplastics could be seen in each soil *** surface layer of microplastics has a large number of pores characterized with a length of 50μm and a width of about 5-10μm,which might be an easy oxidation site for *** oxidation is continuous,making microplastics continuously decompose into smaller *** abundance of microplastics is negatively correlated with soil *** average abundance of microplastics is 161.50±5.20 pieces/100 g in 0-300 mm soil layer,which is their main enrichment ***,the average abundance of microplastics decreases to 11.20±1.10 pieces/100 g in 400-800 mm soil ***,the average particle size of microplastics is also linearly negatively correlated with soil *** with smaller particle size are easier to migrate as they pass through soil pores under the action of water and *** research can provide s reference for understanding plastic mulch pollution.

关键词： soil microplastics plastic pollution distribution composition

Stability validation on the VLF waveform data of the China-Seismo-Electromagnetic Satellite

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Science China(Technological Sciences) 2022年第12期65卷 3069-3078页

作者： YANG DeHe ZHIMA ZeRen WANG Qiao HUANG JianPing WANG xiuying ZHANG ZhenXia ZHAO ShuFan guo Feng CHENG WanLi LU HengXin SHEN XuHui National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China Henan Earthquake Agency Zhengzhou 450016China

The China-Seismo-Electromagnetic Satellite(CSES),which was launched in February 2018,carries the search coil magnetometer(SCM)and the electric field detector(EFD)to realize the high-resolution electromagnetic field and wave detection in the upper *** to the complexity and variability of the ionospheric environment,the stability of such a high sampling rate and high-precision electromagnetic field detection systems is always an essential link in data processing and the scientific application of *** work evaluates the stability of the very-low-frequency(VLF)band detection by validating the systemic sampling-time differences between SCM and EFD in the VLF burst-mode *** optimal waveform data preprocessing method is put forward according to the noise levels of the VLF burst-mode observation and the inherent design characteristics of *** VLF waveform data of EFD is rebuilt by filling the data gaps among the sampling sub-periods,making it with a similar sample length to *** by precisely intercepting the maximum and minimum values of the burst-mode waveforms,the variation of the sampling-time difference between EFD and SCM is statistically *** show that during the three years'operation,the sampling-time difference between EFD and SCM predominately keeps below 0.5 s,indicating good stability of EFD and SCM on *** we developed an automatic synchronization tool based on the similarity function and STA/LTA(short time average over long time average)characteristic *** tool can effectively realize the precise synchronization between SCM and EFD in the VLF burst-mode *** work is helpful to upgrade the data quality of CSES and provides technical support for electromagnetic wave propagation studies.

关键词： stability CSES EFD SCM sampling-time difference quasiperiodic waves

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可再生能源电解制氢成本分析

储能科学与技术 2020年第3期9卷 688-695页

作者：郭秀盈李先明许壮何广利缪平北京低碳清洁能源研究院北京102211

本文对可再生能源电解制氢成本进行了系统分析,对比了碱性与质子交换膜(PEM)电解制氢的平准化成本(LCOH),并考察了规模效应、氢气压力、压缩与液化及输入功率波动性对碱性与PEM电解制氢成本的影响。结果表明:规模增加可降低制氢成本,所... 详细信息

本文对可再生能源电解制氢成本进行了系统分析,对比了碱性与质子交换膜(PEM)电解制氢的平准化成本(LCOH),并考察了规模效应、氢气压力、压缩与液化及输入功率波动性对碱性与PEM电解制氢成本的影响。结果表明:规模增加可降低制氢成本,所考察的电解系统在规模由1 MW提高至40 MW后,装置的固定成本降幅40%以上,由于电费是主要成本,平准化成本(LCOH)降幅小于25%。在固定成本投入无明显增加的情况下高压电解制氢可明显降低制氢成本,随着电解氢气压力由1 atm (1 atm=101.325 k Pa)提高至30 atm,进一步压缩至700 atm的成本由1$/kg降至0.3$/kg;液化成本受规模影响显著,1 MW电解制氢增至40 MW时制氢并液化的平准化成本(LCOH)从8.7$/kg降至5.3$/kg;由于PEM对可再生能源波动具有良好的适应性,在波动性功率输入时,随着低功率(<20%额定功率)波动性的增加,PEM的LCOH成本可以优于碱性电解。随着碱性与PEM电解技术的进步,二者优劣仍需针对具体情况进行分析讨论。

关键词：电解制氢平准化成本压缩液化波动性

上海市中老年女性绝经相关症状及绝经相关知识认知现状调查

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老年医学与保健 2024年第1期30卷 159-163页

作者：陈秀英陈曦黄润泽郭婷顾超邹世恩李斌复旦大学附属妇产科医院妇科上海200011

目的了解上海市40岁以上中老年女性绝经相关症状的发生情况及对绝经相关知识的认知现状,为加强绝经过渡期及绝经后期女性健康保健及管理工作提供参考。方法2021年1月—2021年12月,随机选择上海市年龄≥40岁的女性进行问卷调查,并以改良K... 详细信息

目的了解上海市40岁以上中老年女性绝经相关症状的发生情况及对绝经相关知识的认知现状,为加强绝经过渡期及绝经后期女性健康保健及管理工作提供参考。方法2021年1月—2021年12月,随机选择上海市年龄≥40岁的女性进行问卷调查,并以改良Kupperman评分量表评估其绝经相关症状发生情况。结果共收调查问卷5441份,其中有效问卷5200份,有效率95.57%。受调查人群平均年龄为(51.7±7.0)岁,平均身高(160.42±5.07)cm,平均体质量(58.94±8.01)kg,平均BMI(22.55±2.75)kg/m^(2)。出现绝经综合征者达77%,其中重度占10.15%,中度占34.37%,绝经综合征的主要症状报告率居前五位的依次为疲乏,易激动,肌肉、骨关节痛,失眠和头痛。23.03%~36.55%对绝经相关知识认识不清或存在错误认知,41.63%的调查对象不知道绝经激素治疗;46.31%调查对象不接受绝经激素治疗;48.23%不会推荐身边的适龄女性或者亲友进行绝经激素治疗;影响受调查人群接受激素治疗的主要原因中依次是不了解安全性和有效性(66.60%)与激素治疗的风险(45.94%)等。结论40岁以上女性中绝经综合征的报告率较高,但在一定程度上存在认知缺乏,尤其是对激素补充治疗;不了解安全性和有效性与激素治疗的风险是影响接受激素治疗的主要原因,加强科普宣教和健康管理非常重要。

关键词：中老年绝经过渡期绝经后期绝经综合征激素补充治疗

Role of PIVKA-II in screening for malignancies at a hepatobiliary andpancreatic disease center: A large-scale real-world study

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iLIVER 2022年第4期1卷 209-216页

作者： Chenghao Ge Mingjie Luo Kaiyuan guo Dong Zhu Ning Han Tengjiao Wang xiuying Zhao Department of Clinical Laboratory Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China Tsinghua Clinical Research Institute Tsinghua UniversityBeijing 100084China School of Medicine Tsinghua UniversityBeijing 100084China State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangzhouGuangdong 510060China

Background and aims:Protein induced by vitamin K absence or antagonist II(PIVKA-II)is a well-accepted biomarker for diagnosing hepatocellular carcinoma(HCC).Although nonspecific increase of PIVKA-II has been reported,real-world evidence remains *** on real-world data,this study aimed to comprehensively describe the use of PIVKA-II at a hepatobiliary and pancreatic disease center and to assess its utility for the initial screening of HCC or other hepatobiliary–pancreatic ***:This real-world retrospective study is based on the PIVKA-II results of 16,215 individuals and other relevant laboratory test(alpha-fetoprotein[AFP],carbohydrate antigen 19-9[CA19-9],liver function,blood coagulation indicators,hepatitis B virus,and hepatitis C virus).However,only the first PIVKA-II results of 7809 eligible individuals were ***-group comparisons,correlation analysis,and receiver operating characteristic curve analysis were ***:PIVKA-II results were abnormal in patients with HCC(55.9%),biliary carcinoma(BC,13.4%),gastroin-testinal and pancreatic cancer(6.3%),and benign diseases(23.5%)as well as in healthy individuals(0.92%).The area under the curve of PIVKA-II for detecting malignancies was 0.7754(0.7620–0.7688),whereas that for detecting HCC was 0.7509(0.7357–0.7662).Stratifying the PIVKA-II values or combining PIVKA-II with AFP or CA19-9 helped improve the diagnostic performance of PIVKA-II for ***-II values were significantly positively correlated with AST in patients with HCC and with bilirubin in patients with ***:This study determined the role of PIVKA-II in malignancy screening at hepatobiliary and pancreatic disease *** was also noted that the diagnostic efficacy of PIVKA-II for HCC improved after combining PIVKA-II with AFP or stratifying its value.

关键词： Protein induced by vitamin K absence Or antagonist II Hepatocellular carcinoma Hepatobiliary and pancreatic diseases Real-world study

王有鹏教授运用“分消走泄”法论治小儿慢性胃炎

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西部中医药 2024年第2期37卷 40-43页

作者：梁嫄潘光霞司秀影郭峥刘璐佳王有鹏黑龙江中医药大学黑龙江哈尔滨150036 黑龙江中医药大学附属第二医院黑龙江哈尔滨150000

王有鹏教授认为慢性胃炎的病机是脾为湿困,气机壅滞,他常运用“分消走泄”法治疗慢性胃炎,针对初期、后期不同病机灵活变通,在宣通气机、分消湿邪的基础上,分别运用祛湿运脾、消导和胃、疏肝理气、活血止血之法,标本兼治,疗效显著。

关键词：胃炎慢性分消走泄调脾益胃小儿王有鹏