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Microstructure and property of the Ti-24Al-15Nb-1.5Mo/TC11 joint welded by electron beam welding

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International Journal of Minerals,Metallurgy and Materials 2009年第5期16卷 568-575页

作者： ying-ying Liu Ze-kun Yao Hong-zhen guo Hang-hang yang College of Materials Science and Engineering Northwestern Polytechnical University Xi＇an 710072 China

The Ti-24Al-15Nb-1.5Mo alloy, in the as-forged and heat-treated states, was joined to the as-forged TC 11 titanium alloy by electron beam welding with the heat inputs of 135 and 150 kJ/m. Then the microstructure and property of the Ti-24Al-15Nb- 1.5Mo/TC 11 welding interface were investigated. The results show that the phase constitution of the weld is not related to the heat input, and is mainly composed of α＇ phase. Moreover, the intermetallic phases of TiEAlNb, MoNb, NbaAl, and TiAl3 are formed in the weld zone. Therefore, the microhardness value of the weld zone is higher than that of the other portions in the same sample. The profile of the weld is asymmetrically fimnel-like. The grain sizes of the weld and its heat-affected zones are increased with increasing heat input. There is an obvious difference in the element content of the welding interface; only the alloying elements in the fusion zone reach a new balance during solidification.

关键词： titanium alloys electron beam welding heat input microstructure property

Accelerating the solving of mechanical equilibrium caused by lattice misfit through deep learning method

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Advances in Manufacturing 2024年第3期12卷 512-521页

作者： Chen-Xi guo Hui-ying yang Rui-Jie Zhang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083People’s Republic of China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing100083People’s Republic of China

Precipitation is a common phenomenon that occurs during heat *** is internal stress around the precipitate owing to the lattice misfit between the precipitate and *** internal stress has a significant influence not only on the precipitation kinetics but also on the material *** misfit stress can be obtained by numerically solving the mechanical equilibrium ***,this process is complex and *** developed a new approach based on deep learning to accelerate the solution *** training data were first generated by a phase-field model coupled with elastic mechanical equilibrium equations,which were solved using the finite difference *** obtained precipitate morphologies and corresponding stress distributions were input data for training the physics-informed(PI)UNet *** well-trained PI-UNet model can then be applied to predicting stress distributions with the precipitate morphology as the *** accuracy and efficiency are discussed in this *** results showed that the PI-UNet model was an appropriate approach for quickly predicting the misfit stress between the precipitate and matrix.

关键词： Precipitate Mechanical equilibrium Heat treatment Deep learning

In situ characterization of natural pyrite bioleaching using electrochemical noise technique

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International Journal of Minerals,Metallurgy and Materials 2016年第2期23卷 117-126页

作者： guo-bao Chen Hong-ying yang Hai-jun Li School of Metallurgy Northeastern University

An in situ characterization technique called electrochemical noise（ECN） was used to investigate the bioleaching of natural *** experiments were conducted in four active systems（sulfuric acid,ferric-ion,9k culture medium,and bioleaching solutions）.The ECN data were analyzed in both the time and frequency *** noise impedance spectra obtained from power spectral density（PSD）plots for different systems were compared.A reaction mechanism was also proposed on the basis of the experimental data *** bioleaching system exhibits the lowest noise resistance of 0.101 MΩ The bioleaching of natural pyrite is considered to be a bio-battery reaction,which distinguishes it from chemical oxidation reactions in ferric-ion and culture-medium（9k） *** corrosion of pyrite becomes more severe over time after the long-term testing of bioleaching.

关键词： bioleaching pyrite electrochemical noise biological oxidation chemical oxidation

A 2D Mapping Method Based on Virtual Laser Scans for Indoor Robots

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International Journal of Automation and computing 2021年第5期18卷 747-765页

作者： Xu-yang Shao guo-Hui Tian ying Zhang School of Control Science and Engineering Shandong UniversityJinan 250061China

The indoor robots are expected to complete metric navigation tasks safely and efficiently in complex environments, which is the essential prerequisite for accomplishing other high-level operation tasks. 2 D occupancy grid maps are sufficient to support the robots in avoiding all obstacles in the environments during navigation. However, the maps based on normal laser scans only reflect a horizontal slice of the environment, which may cause the problem of some obstacles missing or misinterpreting their exact boundaries,thereby threatening the safety and efficiency of robot navigation. This paper presents a 2 D mapping method based on virtual laser scans to provide a more comprehensive representation of obstacles for indoor robot navigation. The resulting maps can accurately represent the top-down projected contours of all obstacles no matter where their vertical positions are. The virtual laser scans are initially generated from raw data of an RGB-D camera based on the filtering, projection, and polar-coordinate scanning. The scans are fed directly to the laser-based simultaneous localization and mapping(SLAM) algorithms to update the current map and robot position. Two auxiliary strategies are proposed to further improve the quality of maps by reducing the impact of the narrow field of view and the blind zone of the RGB-D camera on the observations. In this paper, the improved virtual laser generation method makes the extracted 2 D observations fit the laser-based SLAM algorithms, and two auxiliary strategies are novel ways to improve map quality. The generated maps can reflect the comprehensive obstacle information in indoor environments with good accuracy. The comparative experiments are carried out based on four simulation scenarios and three real-world scenarios to prove the effectiveness of our 2 D mapping method.

关键词： 2D mapping indoor robots virtual laser mapping auxiliary strategies safe navigation

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短期增温对紫花针茅草原土壤微生物群落的影响

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植物生态学报 2018年第1期42卷 116-125页

作者：王军王冠钦李飞彭云峰杨贵彪郁建春周国英杨元合中国科学院植物研究所植被与环境变化国家重点实验室北京100093 中国科学院大学北京100049 中国科学院西北高原生物研究所藏药研究重点实验室西宁810008

土壤微生物是生态系统碳循环的重要参与者和调控者。全球变暖可能对土壤微生物群落产生影响,加速陆地生态系统向大气中释放碳,进而引起陆地碳循环对气候变暖的正反馈。然而,目前学术界对土壤微生物群落如何响应气候变暖等问题认识不足,... 详细信息

土壤微生物是生态系统碳循环的重要参与者和调控者。全球变暖可能对土壤微生物群落产生影响,加速陆地生态系统向大气中释放碳,进而引起陆地碳循环对气候变暖的正反馈。然而,目前学术界对土壤微生物群落如何响应气候变暖等问题认识不足,尤其是缺乏低温干旱条件下土壤微生物对增温响应的实验证据。为此,该文依托青藏高原紫花针茅(Stipa purpurea)草原建立的增温实验平台,基于磷脂脂肪酸(PLFA)方法测定了2015和2016年生长季表层(0–10 cm)土壤微生物各类群的生物量,在此基础上揭示气候变暖对紫花针茅草原土壤微生物群落结构的影响。结果显示,短期增温处理导致2015和2016年生长季(5–10月)的表层土壤温度均显著提高1.6℃,同时也导致土壤含水量显著下降了3.4%和2.4%(体积分数),但并没有显著改变土壤化学性质及归一化植被指数。增温处理下,两年生长季旺期(8月)的微生物生物量碳(MBC)含量分别为749.0和844.3 mg·kg^(–1),微生物生物量氮(MBN)含量为43.1和102.1 mg·kg^(–1),微生物生物量碳氮比分别为17.9和8.4,但实验期间MBC、MBN和微生物生物量碳氮比与对照没有差异。PLFA分析的结果显示细菌在微生物群落中占主导,而丛枝菌根真菌含量最少,增温处理并没有改变不同类群的微生物生物量以及群落结构。进一步的分析显示,土壤温度和含水量是调控土壤微生物群落变异的主要因子,并且增温导致的微生物生物量碳的变化量分别与土壤温度和含水量的变化量呈显著正相关关系。以上结果表明,由于受水分的限制,短期增温对紫花针茅草原土壤微生物群落没有显著影响。

关键词：气候变暖磷脂脂肪酸微生物群落青藏高原高寒草原

Standard Framework Construction of Technology and Equipment for Big Data in Crop Phenomics

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Engineering 2024年第11期42卷 175-184页

作者： Weiliang Wen Shenghao Gu ying Zhang Wanneng yang Xinyu guo Information Technology Research Center Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China Beijing Key Lab of Digital Plant National Engineering Research Center for Information Technology in AgricultureBeijing 100097China National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research Huazhong Agricultural UniversityWuhan 430070China

Crop phenomics has rapidly progressed in recent years due to the growing need for crop functional geno-mics,digital breeding,and smart *** this advancement,the lack of standards for the cre-ation and usage of crop phenomics technology and equipment has become a bottleneck,limiting the industry’s high-quality *** paper begins with an overview of the crop phenotyping indus-try and presents an industrial mapping of technology and equipment for big data in crop *** analyzes the necessity and current state of constructing a standard framework for crop ***,this paper proposes the intended organizational structure and goals of the standard *** details the essentials of the standard framework in the research and development of hardware and equipment,data acquisition,and the storage and management of crop phenotyping ***,it discusses promoting the construction and evaluation of the standard framework,aiming to provide ideas for developing a high-quality standard framework for crop phenotyping.

关键词： Crop phenomics Big data Phenotyping technology and equipment Standard framework Industrial mapping

A comparison of different methods for preserving plant molecular materials and the effect of degraded DNA on ddRAD sequencing

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Plant Diversity 2018年第3期40卷 106-116页

作者： ying guo guoQian yang Yunmei Chen Dezhu Li Zhenhua guo Germplasm Bank of Wild Species Kunming Institute of Botany Chinese Academy of Sciences Kunming 650201 China University of Chinese Academy of Sciences Beijing 100049 China

Obtaining high-quality plant materials for experiments is challenging for many research ***, it is of special importance to determine the best method for preserving biological macromolecules like DNA, which degrade over time. Although some research has demonstrated that DNA degradation has little effect on traditional molecular markers, the effects of DNA degradation on dd RADseq, a popular reduced-representation sequencing technology, have not been adequately investigated. In this study, we first chose six woody bamboo species(Bambusoideae, Poaceae) to explore appropriate methods for preserving molecular materials with two DNA extraction approaches. Then we sequenced twenty-one bamboos and examined the effects of DNA quality on data generation using the dd RAD-seq technique(Midd RAD-seq). Finally, we reconstructed phylogenies of twenty woody bamboo species. We found that the integrity of dry-powdered DNA was preserved longer than that of TE-dissolved DNA,regardless of whether the DNA was extracted by a modified CTAB protocol or DNAsecure plant kit. The dd RAD-seq data were robust, except when DNA was severely degraded. In addition, we resolved the phylogenetic positions of the sampled Phyllostachys spp. Our results suggest that dry-powdered DNA is the most appropriate preservation method for plant molecular materials. Furthermore, a moderate level of DNA degradation has little effect on reduced representation sequencing techniques represented by dd RAD-seq.

关键词： Molecular materials DNA extraction and preservation DNA quality ddRAD-seq Bamboo Phylogeny

Intrinsic thermal stability of inverted perovskite solar cells based on electrochemical deposited PEDOT

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Journal of Energy Chemistry 2023年第8期83卷 445-453,I0011页

作者： Congtan Zhu Jing Gao Tian Chen Xueyi guo ying yang School of Metallurgy and Environment Central South UniversityChangsha 410083HunanChina Laboratory of Photonics and Interfaces Ecole Polytechnique Fédérale de Lausane Lausanne 1015witzeland

Thermal stability of perovskite materials is an issue impairing the long-term operation of inverted perovskite solar cells(PSCs). Herein, the thermal attenuation mechanism of the MAPb I3films that deposited on two different hole transport layers(HTL), poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS) and poly(3,4-ethylenedioxythiophene)(PEDOT), is comprehensively studied by applying a heat treatment at 85℃. The thermal stress causes the mutual ions migration of I, Pb and Ag through the device, which leads to the thermal decomposition of perovskite to form Pb I2. Interestingly, we find that I ions tend to migrate more towards electron transport layer(ETL) during heating, which is different with the observation of I ions migration towards HTL when bias pressure is applied. Moreover, the use of electrochemical deposited PEDOT as HTL significantly decreases the defect density of MAPb I3films as compared to PEDOT:PSS supported one. The electrochemical deposition PEDOT has good carrier mobility and low acidity, which avoids the drawbacks of aqueous PEDOT:PSS. Accordingly, the inverted PSCs based on PEDOT show superior durability than that with PEDOT:PSS. Our results reveal detailed degradation routes of a new kind of inverted PSCs which can contribute to the understanding of the failure of thermal-aged inverted PSCs.

关键词： Inverted perovskite solarcells CH_(3)NH_(3)Pbl_(3) Thermal stability Electrochemical deposition PEDOT

山柰酚调节IL-6/STAT3信号通路对妊娠糖尿病大鼠炎症反应的影响

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医学分子生物学杂志 2025年第1期22卷 41-47页

作者：郭艳苓杨颖蒋天从承德市妇幼保健院(承德市儿童医院)产科河北省承德市067000 唐山市妇幼保健院妇产科河北省唐山市063000

目的探讨山柰酚(kaempferol,Kpf)调节白细胞介素-6(interleukin-6,IL-6)/信号转导与转录激活子3(signal transducer and activator of transcription 3,STAT3)信号通路对妊娠糖尿病(gestational dia-betes mellitus,GDM)大鼠炎症反应的影响。方法雌雄同笼与高脂高糖喂养联合腹腔注射链脲佐菌素(streptozotocin,STZ)构建GDM大鼠模型,将造模成功大鼠按照随机数字表达分为Model组、Kpf低、中、高剂量组、激活剂组(IL-6/STAT3通路激活剂rIL-6),每组12只,同批12只妊娠大鼠作为control组,各组腹腔注射相应药物,每天1次,直到妊娠19 d。罗氏血糖仪测量大鼠空腹血糖(fasting blood glucose,FBG);分析各组大鼠妊娠结局;ELISA法测定大鼠血清空腹胰岛素(fasting insulin,FINS)及胎盘中白细胞介素(interleukin,IL)-6、IL-1β、肿瘤坏死因子(tumor necrosis factor-α,TNF-α)水平;苏木精伊红(hematoxylin-eosin,HE)染色观察大鼠胎盘组织中病理损伤;TUNEL染色检测胎盘组织细胞凋亡;蛋白质印迹测定胎盘中IL-6/STAT3通路蛋白表达。结果与control组比较,Model组大鼠FBG、FINS、HOMA-IR、胎鼠质量、IL-6、IL-1β、TNF-α水平、胎盘组织IL-6、p-STAT3/STAT3水平及细胞凋亡率增加,活胎率、窝产子数下降(P<0.05);相较于Model组,Kpf低、中、高剂量组大鼠FBG、FINS、HOMA-IR、胎鼠质量、IL-6、IL-1β、TNF-α水平、胎盘组织IL-6、p-STAT3/STAT3水平及细胞凋亡率下降,活胎率、窝产子数增加(P<0.05);相较于Kpf高剂量组,激活剂组上述指标变化均显著逆转(P<0.05)。结论Kpf可能通过抑制IL-6/STAT3信号通路降低GDM大鼠胎盘炎症,减轻胰岛素抵抗。

关键词：妊娠糖尿病山柰酚白细胞介素-6 信号转导与转录激活子3 炎症胰岛素抵抗