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Integrating remotely sensed water stress factor with a crop growth model for winter wheat yield estimation in the North China Plain during 2008–2018

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The Crop Journal 2022年第5期10卷 1470-1482页

作者： Wen Zhuo Shibo Fang Dong Wu Lei Wang Mengqian Li jiansu zhang Xinran Gao State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Collaborative Innovation Centre on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044JiangsuChina School of Geography and Earth Sciences McMaster UniversityHamiltonOntario L8S 4L8Canada

Accurate estimation of regional-scale crop yield under drought conditions allows farmers and agricultural agencies to make well-informed decisions and guide agronomic management. However, few studies have focused on using the crop model data assimilation(CMDA) method for regional-scale winter wheat yield estimation under drought stress and partial-irrigation conditions. In this study, we developed a CMDA framework to integrate remotely sensed water stress factor(MOD16 ET PET) with the WOFOST model using an ensemble Kalman filter(En KF) for winter wheat yield estimation at the regional scale in the North China Plain(NCP) during 2008–2018. According to our results, integration of MOD16 ET PETwith the WOFOST model produced more accurate estimates of regional winter wheat yield than open-loop simulation. The correlation coefficient of simulated yield with statistical yield increased for each year and error decreased in most years, with r ranging from 0.28 to 0.65 and RMSE ranging from 700.08 to1966.12 kg ha. Yield estimation using the CMDA method was more suitable in drought years(r = 0.47, RMSE = 919.04 kg ha) than in normal years(r = 0.30, RMSE = 1215.51 kg ha). Our approach performed better in yield estimation under drought conditions than the conventional empirical correlation method using vegetation condition index(VCI). This research highlighted the potential of assimilating remotely sensed water stress factor, which can account for irrigation benefit, into crop model for improving the accuracy of winter wheat yield estimation at the regional scale especially under drought conditions, and this approach can be easily adapted to other regions and crops.

关键词： WOFOST Evapotranspiration Drought Data assimilation Winter wheat yield

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铁素体／贝氏体双相钢的变形和断裂特性

材料研究学报 2009年第1期23卷 83-88页

作者：蔡明晖丁桦张建苏李龙唐正友东北大学材料与冶金学院沈阳110004 上海宝钢集团公司技术中心上海201900 日本国立材料科学研究所东京3050047

对一种低碳硅锰钢进行TMCP实验，获得了不同铁素体形态的铁素体／贝氏体双相钢（FB钢）．研究了FB钢在单轴拉伸下的变形行为及断裂特性，结果表明：在均匀塑性变形阶段，FB钢的瞬时加工硬化指数n＊值与真应变ε的关系曲线可分为n＊值较... 详细信息

对一种低碳硅锰钢进行TMCP实验，获得了不同铁素体形态的铁素体／贝氏体双相钢（FB钢）．研究了FB钢在单轴拉伸下的变形行为及断裂特性，结果表明：在均匀塑性变形阶段，FB钢的瞬时加工硬化指数n＊值与真应变ε的关系曲线可分为n＊值较高、n＊值随ε缓慢下降以及n＊值随ε迅速下降三个阶段．与等轴铁素体／贝氏体双相钢相比，准多边形铁素体／贝氏体双相钢的强度和低应变区的n＊值均比较高．FB钢拉伸试样颈缩区的孔洞或微裂纹产生在F—B相界面附近和铁素体内，有助于减弱裂纹尖端附近的局部应力集中，改善钢材的抗裂纹扩展性能．

关键词：金属材料铁素体/贝氏体双相钢单轴拉伸变形行为断裂特性

700 MPa级高强热轧双相钢DP700的开发

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特殊钢 2020年第6期41卷 77-80页

作者：殷胜张建苏朱红丹西北工业大学材料科学与工程学院西安710072 宝钢股份梅钢公司技术中心南京210039 宝山钢铁股份有限公司研究院上海201900 宝钢股份梅钢公司制造管理部南京210039

阐述了在宝钢梅山基地1780热轧机生产线上开发的700MPa级热轧双相钢DP700(/%:C 0.08~0.12,Si 0.08~0.12,Mn 1.30~1.150,P≤0.015,S≤0.005,Cr0.50~0.70,Ca≥0.0015,Al≥0.015)工艺和性能,该钢板表面质量优良,屈服强度≥400 MPa,抗拉强度≥700 MPa,断后伸长率≥17%(b=20 mm,L_0=80 mm),扩孔率≥35%,50%存活率的疲劳极限达475 MPa。结果表明,DP700钢是一种具有良好应用前景的新型汽车零部件材料。

关键词：汽车用钢双相钢 700 MPa级高疲劳性能

NiCrAlYSi包覆型涂层发动机试车“黑斑”的分析

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材料工程 1999年第4期27卷 16-19页

作者：霍晓张建苏王蓓蕾吴凤筠韩雅芳北京航空材料研究院

某型航空发动机的二级涡轮导向叶片用定向凝固的ＩＣ６合金精铸而成，叶身表面采用电弧镀和直流磁控溅射工艺涂覆ＮｉＣｒＡｌＹＳｉ涂层。经过３７９ｈ的发动机地面试车后，发现在叶背和叶盆部位的涂层表面出现了一些大小不等的黑斑。... 详细信息

某型航空发动机的二级涡轮导向叶片用定向凝固的ＩＣ６合金精铸而成，叶身表面采用电弧镀和直流磁控溅射工艺涂覆ＮｉＣｒＡｌＹＳｉ涂层。经过３７９ｈ的发动机地面试车后，发现在叶背和叶盆部位的涂层表面出现了一些大小不等的黑斑。采用扫描电镜、Ｘ衍射、电子探针和能谱分析方法，就黑斑对涂层和基体合金的影响及黑斑的形成原因进行了研究。

关键词： Ni3Al基合金涂层试车黑斑航空发动机

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宁钢车轮钢N420CL生产实践

宝钢技术 2010年第4期3卷 22-24,71页

作者：赵彦灵张建苏柳晨岚仝广宁波钢铁有限公司浙江宁波315807 宝山钢铁股份有限公司上海201900

介绍宁钢1 780mm热连轧生产线上成功开发的车轮钢N420CL。车轮用N420CL钢考虑"低成本、高效率"的生产经营策略,成分采用低碳低硅设计以避开亚包晶区,保证适合直装热送的连铸坯表面质量;工序上采用直装热送工艺,以适应宁钢特色的快捷交... 详细信息

介绍宁钢1 780mm热连轧生产线上成功开发的车轮钢N420CL。车轮用N420CL钢考虑"低成本、高效率"的生产经营策略,成分采用低碳低硅设计以避开亚包晶区,保证适合直装热送的连铸坯表面质量;工序上采用直装热送工艺,以适应宁钢特色的快捷交货方式。目前N420CL钢已成功投向市场。

关键词：车轮钢屈服强度抗拉强度冷成型

Influence of welding heat input on the HAZ of hot-rolled high strength steel

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Baosteel Technical Research 2010年第S1期4卷 55-页

作者： SUN Guang,HUANG Zhenru,zhang jiansu and CHEN Zhipeng Research Institute,Baoshan Iron & Steel Co.,Ltd.,Shanghai 201900,China

When welding the hot-rolled high strength steel manufacture by thermal-mechanical controlled process(TMCP),there has a soften zone in the heat affected zone(HAZ).Evaluate the welding quality though the research on the influence of softened zone's width,hardness,strength by the different heat input. Take the 8mm thickness QSTE700TM that produced by Baosteel as an example and used the gas metal arc welding(GMAW,the CO_2 and Ar as the shield gas) welding method choose the high strength welding wire ER76-G(GB)、ER110S-G(AWS) as the welding *** the welding heat input range from 6.8 kJ/cm to 43.6 kJ/cm and found that as the heat input increased the tensile strength,fatigue strength of the welding structure and the hardness of the HAZ will *** when using the lower heat input the quality of the welding structure can fulfil the usage request *** give the advise to increased the welding quality in detail:when keep the heat input in the scope of Q =6.8 -20 kJ/cm the good welding quality can be achieved *** the further research approve that when usage the lower strength welding consumer such as the ER50-6(GB)、ER70S-G(AWS) the welding structure can also achieved high quality for which the tensile strength can get about 700 MPa when use the lower welding heat *** not only keep the welding quality,but also decreased the cost.

关键词： welding QSTE700TM GMAW tensile strength

Lycium barbarum glycopeptide(wolfberry extract)slows N-methyl-N-nitrosourea-induced degradation of photoreceptors

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Neural Regeneration Research 2024年第10期19卷 2290-2298页

作者： Qihang Kong Xiu Han Haiyang Cheng Jiayu Liu Huijun zhang Tangrong Dong jiansu Chen Kwok-Fai So Xuesong Mi Ying Xu Shibo Tang Department of Ophthalmology Aier Eye HospitalJinan UniversityGuangzhouGuangdong ProvinceChina Department of Ophthalmology The First Affiliated Hospital of Jinan UniversityGuangzhouGuangdong ProvinceChina Guangdong-Hong Kong-Macao Institute of CNS Regeneration Key Laboratory of CNS Regeneration(Ministry of Education)Jinan UniversityGuangzhouGuangdong ProvinceChina Department of Ophthalmology Guangzhou Panyu Central HospitalGuangzhouGuangdong ProvinceChina School of Stomatology Jinan UniversityGuangzhouGuangdong ProvinceChina Aier Academician Station ChangshaHunan ProvinceChina Co-Innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina State Key Laboratory of Brain and Cognitive Sciences Hong Kong Special Administrative RegionChina

Photoreceptor cell degeneration leads to blindness, for which there is currently no effective treatment. Our previous studies have shown that Lycium barbarum(L. barbarum) polysaccharide(LBP) protects degenerated photoreceptors in rd1, a transgenic mouse model of retinitis pigmentosa. L. barbarum glycopeptide(Lb GP) is an immunoreactive glycoprotein extracted from LBP. In this study, we investigated the potential protective effect of Lb GP on a chemically induced photoreceptor-degenerative mouse model. Wild-type mice received the following: oral administration of Lb GP as a protective pre-treatment on days 1–7;intraperitoneal administration of 40 mg/kg N-methylN-nitrosourea to induce photoreceptor injury on day 7;and continuation of orally administered Lb GP on days 8–14. Treatment with Lb GP increased photoreceptor survival and improved the structure of photoreceptors, retinal photoresponse, and visual behaviors of mice with photoreceptor degeneration. Lb GP was also found to partially inhibit the activation of microglia in N-methyl-N-nitrosourea-injured retinas and significantly decreased the expression of two pro-inflammatory cytokines. In conclusion, Lb GP effectively slowed the rate of photoreceptor degeneration in N-methyl-N-nitrosourea-injured mice, possibly through an anti-inflammatory mechanism, and has potential as a candidate drug for the clinical treatment of photoreceptor degeneration.

关键词： anti-inflammation inherited retinal diseases Lycium barbarum glycopeptide N-methyl-N-nitrosourea opsin photoreceptor reactive gliosis retinal degeneration retinitis pigmentosa rhodopsin

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琼脂糖凝胶的光学特性

红外与激光工程 2016年第7期45卷 125-131页

作者：张仁梅张军谢梦圆陈建苏暨南大学光电工程系广东广州510632 中国科学院长春光学精密机械与物理研究所应用光学国家重点实验室吉林长春130033 暨南大学医学院眼科研究所广东广州510632

为了研究应用于生物细胞打印的琼脂糖凝胶的光学特性,将不同比例的琼脂糖粉末与蒸馏水混合后加热,溶解冷却形成不同浓度的琼脂糖凝胶。测量琼脂糖热溶液冷却过程中55℃时的琼脂糖溶液的折射率及琼脂糖凝胶的折射率。通过对比细胞培养液... 详细信息

为了研究应用于生物细胞打印的琼脂糖凝胶的光学特性,将不同比例的琼脂糖粉末与蒸馏水混合后加热,溶解冷却形成不同浓度的琼脂糖凝胶。测量琼脂糖热溶液冷却过程中55℃时的琼脂糖溶液的折射率及琼脂糖凝胶的折射率。通过对比细胞培养液的折射率,获得作为生物打印基质材料和生物支架的琼脂糖凝胶最佳浓度为0.786%。测量琼脂糖凝胶的可见、近红外透射光谱及衰减全反射红外吸收光谱,结果显示琼脂糖凝胶在400~1 100 nm波段没有特征吸收峰,而且最大吸收只有0.171Abs;在红外波段琼脂糖凝胶的吸收特性与细胞培养液基本相同,细胞培养液在2 966 cm-1处的特征吸收峰是培养液独有的。对琼脂糖凝胶表面的激光散射特性进行研究,结果表明,440 nm激光的散射最强,532 nm激光散射最弱;琼脂糖凝胶浓度越小,散射越强。

关键词：琼脂糖热冲击生物打印光谱吸收特性

DC-UMnet网络解全息欠采样包裹相位的方法

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红外与激光工程 2024年第10期53卷 260-270页

作者：张晶晶李建素党长营陈颢文杨钊中北大学机械工程学院山西太原030051

为了解决数字全息数值重构时,欠采样包裹相位的解包裹问题,提出了一种DC-UMnet网络解欠采样包裹相位的空间相位解包裹方法。DC-UMnet网络以U-net网络的解码器-编码器为框架,在编码部分融入Mobilenetv1的轻量级深度学习网络,以降低模型... 详细信息

为了解决数字全息数值重构时,欠采样包裹相位的解包裹问题,提出了一种DC-UMnet网络解欠采样包裹相位的空间相位解包裹方法。DC-UMnet网络以U-net网络的解码器-编码器为框架,在编码部分融入Mobilenetv1的轻量级深度学习网络,以降低模型复杂程度、参数数量和运算成本;在解码部分提出了一种复杂的卷积模块-双通道模块(Dual-Channel Block)代替原来U-net网络中的3×3卷积,其在解码过程中更好地融合了特征,从而更好地解调欠采样包裹相位。同时使用SmoothL1Loss损失函数计算损失值,激活函数使用ReLU6,最后对欠采样模拟数据集进行了训练,并对实验获取的欠采样包裹相位图进行了实验验证。仿真结果表明,通过大量的模拟测试,验证了相比于DCT方法和U-net网络,DC-UMnet网络的结构性相似指数值分别提高了约4.38倍和0.77倍,在添加噪声后测试结果表明,DC-UMnet网络的结构性相似指数值分别提高了约4.68倍和0.86倍,适合应用到需要准确地进行欠采样相位解包裹中去;以欠采样微孔为对象的实验结果表明,文中方法获得微孔纵向尺寸的准确率为91.2%,验证了文中提出网络模型的可行性。该研究满足了欠采样包裹相位高质量解包裹的要求,为解决欠采样条件下的相位解包裹问题提供了新的思路方法。

关键词：数字全息欠采样 DC-UMnet网络相位解包裹