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酰肼成核剂对聚乳酸结晶和力学性能的影响

材料科学与工程学报 2024年第3期42卷 427-434页

作者：张靖倩曾广胜彭军胡灿孟聪李玲郑和淇湖南工业大学包装与材料工程学院湖南株洲412000

为提高聚乳酸结晶度、改善韧性,采用熔融共混向聚乳酸(PLA)中分别加入了成核剂己二酸二苯基二酰肼(SDA210)和癸二酸二苯基二酰肼(SDA356),通过差示扫描量热仪、X射线衍射仪、偏光显微镜等表征手段测试研究了两种成核剂含量对聚乳酸结晶... 详细信息

为提高聚乳酸结晶度、改善韧性,采用熔融共混向聚乳酸(PLA)中分别加入了成核剂己二酸二苯基二酰肼(SDA210)和癸二酸二苯基二酰肼(SDA356),通过差示扫描量热仪、X射线衍射仪、偏光显微镜等表征手段测试研究了两种成核剂含量对聚乳酸结晶和力学性能的影响。研究结果表明:SDA210和SDA356都是PLA的有效成核剂。当SDA210添加量为1.0%时,对PLA成核效果达到最佳,其结晶度较纯PLA提高了10.21%;而SDA356添加量为0.8%时成核效果最好,其结晶度较纯PLA提高了12.57%。两种成核剂的加入都可以提高聚乳酸复合材料的冲击性能。PLA/0.8%SDA356的无缺口冲击强度最好,达到170.08 J/M,与纯PLA相比增加了31.3%。在相同添加量的情况下,成核剂SDA356的成核效果和增韧效果均优于SDA210。

关键词：聚乳酸酰肼成核剂结晶韧性

面向工业膏体浓度监测的体系化智能视觉信息融合模型

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北京邮电大学学报 2024年第4期47卷 83-89页

作者：王贺正马博渊李潇睿郭利杰刘光生北京科技大学北京材料基因工程高精尖创新中心北京100083 北京科技大学钢铁共性技术协同创新中心北京100083 北京科技大学智能科学与技术学院北京100083 北京科技大学顺德创新学院佛山528300 矿冶科技集团有限公司北京100160

针对膏体充填技术中对于膏体浓度监控方法存在的精准度低、仪器使用寿命短、测量耗时长、因安全问题导致使用受限等局限性,提出了一种双流视觉信息融合模型以实现膏体浓度自动化准确估计,以减少膏体浓度监测对人工的需求,增加矿场的自... 详细信息

针对膏体充填技术中对于膏体浓度监控方法存在的精准度低、仪器使用寿命短、测量耗时长、因安全问题导致使用受限等局限性,提出了一种双流视觉信息融合模型以实现膏体浓度自动化准确估计,以减少膏体浓度监测对人工的需求,增加矿场的自动化程度,促进体系化人工智能在智能采矿领域中的应用。所提模型以卷积神经网络模型为基础,使用双流结构,通过分析膏体视频及相应的光流信息,学习提取其中的空间特征和时间特征,形成对膏体视频的双流特征感知表示;特征融合模块进一步强化对有效特征的识别,使模型能够对膏体浓度进行非接触式的准确监测。在此基础上,采集实际生产环境下膏体视频数据并构建真实的膏体视频-浓度数据集,并以此数据集对所提模型进行验证。实验结果表明,所提模型在真实膏体视频数据集中识别准确率能够达到94.16%,在同等条件下准确率较其他深度学习模型高出3.47%,实现了在生产环境下对膏体浓度进行实时准确监测的目的。

关键词：膏体充填膏体浓度准确估计视频分类多模态

Projection of Heat Injury to Single-Cropping Rice in the Middle and Lower Reaches of the yangtze River, China under Future Global Warming Scenarios

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Journal of Meteorological Research 2019年第2期33卷 363-374页

作者： Xiaomin LYU guangsheng ZHOU Mengzi ZHOU li ZHOU Yuhe JI State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology

Based on simulation results from the 16 CMIP5 model runs under three Representative Concentration Pathways(RCP2.6, RCP4.5, and RCP8.5) in combination with the recent five years of growth-stage data from agrometeorological observation stations in the middle and lower reaches of the yangtze River, changes in heat injury and spatial distribution patterns of single-cropping rice in China during the early(2016–35), middle(2046–65), and late(2080–99) 21 st century were projected by using quantitative estimations. Relative to the reference period(1986–2005), the occurrence probabilities of heat injury to single-cropping rice under different RCP scenarios increased significantly, showing a trend of mild > moderate > severe. The occurrence probabilities increased with time and predicted emissions, especially the average and maximum occurrence probabilities, which were ～48% and ～80%,respectively, in the late 21 st century under the RCP8.5 scenario. The spatial patterns of the occurrence probabilities at each level of heat injury to single-cropping rice did not change, remaining high in the middle planting region and low in the east. The high-value areas were mainly in central Anhui and southeastern Hubei provinces, and the areas extended to the northwest and northeast of the cultivation area over time. Under the RCP2.6, RCP4.5, and RCP8.5 scenarios, the total area of heat injury to single-cropping rice showed a significant linear increasing trend of 7.4 × 10~3, 19.9× 10~3, and 35.3 × 10~3 ha yr^(–1), respectively, from 2016 to 2099, and the areas of heat injury were greatest in the late21 st century, accounting for ～25%, ～40%, and ～59% of the cultivation area.

关键词： projection single-cropping rice heat injury climate change China

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基于金矿岩芯的自动工艺矿物学

矿产综合利用 2024年第3期45卷 174-178页

作者：蔡明明李光胜朱幸福徐超孙琪伟王楠山东黄金矿业科技有限公司选冶实验室分公司山东烟台261441 山东黄金矿业(莱州)有限公司三山岛金矿山东烟台261442

这是一篇工艺矿物学领域的论文。山东某石英脉型金矿,金品位2.51 g/t。为对该矿床的进一步开发及选矿工艺研究,对该矿物开展了工艺矿物学研究。本次研究涉及的技术方法包括多元素化学分析、化学物相分析、光学显微镜鉴定、X射线衍射(XRD... 详细信息

这是一篇工艺矿物学领域的论文。山东某石英脉型金矿,金品位2.51 g/t。为对该矿床的进一步开发及选矿工艺研究,对该矿物开展了工艺矿物学研究。本次研究涉及的技术方法包括多元素化学分析、化学物相分析、光学显微镜鉴定、X射线衍射(XRD)分析、矿物自动定量分析(BPMA)、扫描电镜-能谱仪(SEM-EDS)分析等。结果表明:(1)矿石中金矿物绝大多数为银金矿,偶见微量的金银矿和自然金;(2)矿石中金矿物与黄铁矿等硫化物的嵌布关系十分密切,黄铁矿是金矿物的最主要的载体矿物,矿石中单体及裸露金的占有率较高,为58.96%,黄铁矿等硫化物中包裹金的占有率为39.84%,脉石矿物中包裹金的占有率为1.20%;(3)矿石中金矿物粒度分布不均匀,整体粒度较细,矿石中可见粒度+0.020 mm的金矿物颗粒,其占有率为22.08%,-0.020 mm的金矿物占有率为77.92%,其中-0.005 mm的微粒金矿物占有率为24.83%,-0.001 mm的亚微米级微细粒金矿物占有率为0.35%。

关键词：岩芯金矿黄铁矿银金矿工艺矿物学嵌布特征赋存状态

Study on time-resolved fluorescence dynamics of cyanine dye sensitizing AgBr

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Science China(Physics,Mechanics & Astronomy) 2008年第3期51卷 243-250页

作者： yang ShaoPeng FAN ShanShan li ChunLei FAN GuoZhi MENG Tao li XiaoWei FU guangsheng AI XiCheng ZHAO XiaoHui YE JianPing WANG lingXuan College of Physics Science&Technology Hebei UniversityBaoding 071002China Institute of Chemistry Chinese Academy of SciencesBeijing 100080China

The fluorescence spectra of three different dyes adsorbed on the tabular and cubic AgBr microcrystals are obtained by the picosecond time-resolved streak camera technique. The dependence of the ultrafast electron transferring from dye-aggre-gates to the conduction band of AgBr and the efficiency of spectral sensitization on different kinds of dyes with different concentrations is analyzed. Further more,the microcosmic mechanism of the sensitization process is discussed. It is found that the fluorescence decay curves are fitted very well by the double exponential func-tion,consisting of a slow component and a fast one with large amplitude. We con-sider this fast one mainly attributable to the electron transfer from dye J-aggre-gates to the conduction band of AgBr.

关键词： spectral sensitization electron transfer rate Streak Camera AgBr

Response of leaf carbon metabolism and dry matter accumulation to density and row spacing in two rapeseed(Brassica napus L.)genotypes with differing plant architectures

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The Crop Journal 2022年第3期10卷 680-691页

作者： Jie Kuai Xiaoyong li Jianli Ji Zhen li Yan Xie Bo Wang guangsheng Zhou MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the yangtze River College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070HubeiChina Oil Crops Research Institute of Chinese Academy of Agricultural Sciences Wuhan 430070HubeiChina College of Agriculture Jinhua Polytechni3Jinhua 321007ZhejiangChina Haimen Municipal Guidance Station for Crop Cultivation and Technology Haimen 226100JiangsuChina

Biological yield indicates the potential for increasing *** carbon metabolism plays an important role in the biomass accumulation of rapeseed(Brassica napus L.).Field experiments with the hybrid HZ62(with a conventional plant architecture)grown in 2016–2017,and HZ62 and accession 1301(with a compact plant architecture)grown in 2017–2018 were conducted to characterize the physiological and proteomic responses of leaf photosynthetic carbon metabolism to density and row spacing *** densities were set at 15×10;ha^(-1)(D1),30×10^(4)ha^(-1)(D2),and 45×10^(4)ha^(-1)(D3)(main plot),with row spacings of 15 cm(R15),25 cm(R25),and 35 cm(R35)(subplot).Individual and plant population biomass accumulation was greatest at R25,R15,and R15 for D1,D2,and D3,respectively,for both *** comparison with D1 R25,the individual aboveground biomass of HZ62 decreased by60.2%,whereas the population biomass increased by 31.9%,and the individual biomass of genotype1301 decreased by 54.0%and the population biomass increased by 53.9%at D3 *** carbon metabolic enzymes varied between genotypes at flowering *** contrast to D1 R25,at D3 R15 the activities of ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)and sucrose phosphate synthase(SPS)and the contents of starch,sucrose and soluble sugars in leaves were significantly decreased in HZ62 and increased in genotype *** activities of fructose-1,6-bisphosphatase(FBPase)decreased,in consistency with the abundance of fructose-bisphosphate aldolase in *** contrast,sucrose synthase(Su Sy)activity appeared to decrease in both genotypes,but a significant increase in abundance of a protein with sucrose synthase was found in the 1301 genotype by proteomic *** increased density and reduced row spacing,the expression of most key proteins involved in carbon metabolism was elevated,and enzyme activity and carbon assimilate content were increased in 1301,whereas HZ62 showed the opposite trend,indicati

关键词： Rapeseed Density Row spacing Dry matter Leaf carbon metabolism

Variation of net primary productivity and its drivers in China’s forests during 2000-2018

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Forest Ecosystems 2020年第2期7卷 190-200页

作者： Yuhe Ji guangsheng Zhou Tianxiang Luo Yakir Dan li Zhou Xiaomin Lv State Key Laboratory of Severe Weather(LASW) Chinese Academy of Meteorological ScienceBeijing 100081China Key Laboratory of Alpine Ecology and Biodiversity Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Earth&Planetary Sciences Weizmann Institute of Science76100 RehovotIsrael.

Background:Net primary productivity(NPP)in forests plays an important role in the global carbon ***,it is not well known about the increase rate of China’s forest NPP,and there are different opinions about the key factors controlling the variability of forest ***:This paper established a statistics-based multiple regression model to estimate forest NPP,using the observed NPP,meteorological and remote sensing data in five major forest *** fluctuation values of NPP and environment variables were extracted to identify the key variables influencing the variation of forest NPP by correlation ***:The long-term trends and annual fluctuations of forest NPP between 2000 and 2018 were *** results showed a significant increase in forest NPP for all five forest ecosystems,with an average rise of 5.2 gC·m-2·year-1 over *** 90%of the forest area had an increasing NPP range of 0-161 gC·m-2·*** NPP had an interannual fluctuation of 50-269 gC.m-2·year-1 for the five major forest *** evergreen broadleaf forest had the largest *** variability in forest NPP was caused mainly by variations in precipitation,then by temperature ***:All five forest ecosystems in China exhibited a significant increasing NPP along with annual fluctuations evidently during *** variations in China’s forest NPP were controlled mainly by changes in precipitation.

关键词： Net primary production(NPP) Forest ecosystem annual precipitation NPP model Fluctuation Variability

Preparation of κ-carra-Oligosaccharides with Microwave Assisted Acid Hydrolysis Method

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Journal of Ocean University of China 2015年第2期14卷 345-349页

作者： li guangsheng ZHAO Xia LV Youjing li Miaomiao YU Guangli Key Laboratory of Marine Drugs Ministry of Education Shandong Provincial Key Laboratory of Glycoscience and Glycotechnology School of Medicine and PharmacyOcean University of China

A rapid method of microwave assisted acid hydrolysis was established to prepare κ-carra-oligosaccharides. The optimal hydrolysis condition was determined by an orthogonal test. The degree of polymerization （DP） of oligosaccharides was detected by high performance thin layer chromatography （HPTLC） and polyacrylamide gel electrophoresis （PAGE）. Considering the results of HPTLC and PAGE, the optimum condition of microwave assisted acid hydrolysis was determined. The concentration of κ-carrageenan was 5 mgmL-1; the reaction solution was adjusted to pH 3 with diluted hydrochloric acid; the solution was hydrolyzed under microwave irradiation at 100 ℃ for 15 min. Oligosaccharides were separated by a Superdex 30 column （2.6 cm × 90 em） using AKTA Purifier UPC100 and detected with an online refractive index detector. Each fraction was characterized by electrospray ioni- zation mass spectrometry （ESI-MS）. The data showed that odd-numbered κ-carra-oligosaccharides with DP ranging from 3 to 21 could be obtained with this method, and the structures of the oligosaccharides were consistent with those obtained by traditional mild acid hydrolysis. The new method was more convenient, efficient and environment-friendly than traditional mild acid hydrolysis. Our results provided a useful reference for the preparation of oligosaceharides from other polysaccharides.

关键词： κ-carrageenan oligosaccharides microwave degradation acid hydrolysis

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汽车工业伺服电机轴断裂分析与改进

汽车实用技术 2024年第6期49卷 149-154页

作者：焦广胜齐涛李蒙吴冰冰深圳市美信检测技术股份有限公司广东深圳518108 深圳市美信咨询有限公司广东深圳518108

伺服电机在服役三个月时,电机轴突然断裂。通过对电机轴进行外观检查、低倍观察、断口分析、金相分析、化学分析和力学性能分析等试验,对其断裂原因进行探究。结果表明,电机轴断裂模式为疲劳断裂,轴心部硬度偏低导致强度不足,表层网状... 详细信息

伺服电机在服役三个月时,电机轴突然断裂。通过对电机轴进行外观检查、低倍观察、断口分析、金相分析、化学分析和力学性能分析等试验,对其断裂原因进行探究。结果表明,电机轴断裂模式为疲劳断裂,轴心部硬度偏低导致强度不足,表层网状铁素体组织缺陷,以及退刀槽倒角过小加剧应力集中是电机轴发生疲劳断裂的主要原因,热处理工艺欠佳是强度不足的根本原因。同时针对该失效原因提出相应的改进措施,以避免此类事件再次发生。

关键词：伺服电机电机轴调质处理疲劳断裂应力集中