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厄瓜多尔Oriente盆地白垩系Napo组LU亚段沉积模式
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作者 韩立杨 孙雨 +3 位作者 张克鑫 闫百泉 张超前 杨国庆 《海洋地质前沿》 CSCD 北大核心 2024年第5期80-90,共11页
厄瓜多尔Oriente盆地北部白垩系Napo组LU亚段地层油气资源极其丰富,具有较大的油气勘探潜力,由于目前对LU亚段地层沉积模式认识不清晰,极大程度上限制了研究区进一步勘探开发。依据LU亚段岩芯观察、测井、成熟度分析以及镜下薄片等资料... 厄瓜多尔Oriente盆地北部白垩系Napo组LU亚段地层油气资源极其丰富,具有较大的油气勘探潜力,由于目前对LU亚段地层沉积模式认识不清晰,极大程度上限制了研究区进一步勘探开发。依据LU亚段岩芯观察、测井、成熟度分析以及镜下薄片等资料,通过岩芯岩性、结构等岩石学特征,沉积构造、生物遗迹化石、沉积韵律等沉积学特征,以及测井相标志认为,研究区LU亚段地层发育于潮汐作用为主的海陆过渡环境,并在前人研究基础上提出潮控河口湾与陆棚之间存在过渡带沉积,形成了潮控河口湾-过渡带-陆棚沉积体系,识别出潮汐水道、潮汐砂坝、砂坪、海绿石砂席、混合坪、陆棚泥和灰质滩共7种沉积微相,其中,优势储层相带为潮汐水道和潮汐砂坝,砂坪次之。建立研究区潮控河口湾-过渡带-陆棚沉积模式,以期对Oriente盆地白垩系Napo组油气勘探提供有利的科学依据。 展开更多
关键词 沉积模式 沉积微相 潮控河口湾 oriente盆地
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基于改进Oriented R-CNN的旋转框麦穗检测与计数模型
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作者 于俊伟 陈威威 +2 位作者 郭园森 母亚双 樊超 《农业工程学报》 EI CAS CSCD 北大核心 2024年第6期248-257,共10页
为对干扰、遮挡等复杂的田野环境中麦穗进行精准定位与计数,该研究提出了一种改进的Oriented R-CNN麦穗旋转框检测与计数方法,首先在主干网络中引入跨阶段局部空间金字塔(spatial pyramid pooling cross stage partial networks,SPPCSPC... 为对干扰、遮挡等复杂的田野环境中麦穗进行精准定位与计数,该研究提出了一种改进的Oriented R-CNN麦穗旋转框检测与计数方法,首先在主干网络中引入跨阶段局部空间金字塔(spatial pyramid pooling cross stage partial networks,SPPCSPC)模块扩大模型感受野,增强网络感知能力;其次,在颈网络中结合路径聚合网络(PANet,path aggregation network)和混合注意力机制(E2CBAM,efficient two convolutional block attention module),丰富特征图包含的特征信息;最后采用柔性非极大值抑制算法(Soft-NMS,soft-non maximum suppression)优化预测框筛选过程。试验结果显示,改进的模型对复杂环境中的麦穗检测效果良好。相较原模型,平均精确度均值mAP提高了2.02个百分点,与主流的旋转目标检测模型Gliding vertex、R3det、Rotated Faster R-CNN、S2anet和Rotated Retinanet相比,mAP分别提高了4.99、2.49、3.94、2.25和4.12个百分点。该研究方法利用旋转框准确定位麦穗位置,使得框内背景区域面积大幅度减少,为实际观察麦穗生长状况和统计数量提供了一种有效的方法。 展开更多
关键词 图像识别 作物 注意力机制 麦穗 oriented R-CNN
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Effects of orientation on the fatigue crack growth behaviors of the ZK60 magnesium alloy in air and PBS
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作者 Jiaqi Hu Zheng Liu +1 位作者 Zuoliang Ning Hong Gao 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期281-294,共14页
Strong anisotropic corrosion and mechanical properties caused by specimen orientations greatly limit the applications of wrought magnesium alloys.To investigate the influences of specimen orientation,the corrosion tes... Strong anisotropic corrosion and mechanical properties caused by specimen orientations greatly limit the applications of wrought magnesium alloys.To investigate the influences of specimen orientation,the corrosion tests and(corrosion)fatigue crack growth tests were conducted.The rolled and transverse surfaces of the materials show distinct corrosion rate differences in the stable corrosion stage,but the truth is the opposite for the initial stage of corrosion.In air,specimen orientations have a significant influence on the plastic deformation mechanisms near the crack tip,which results in different fatigue fracture surfaces and cracking paths.Compared with R-T specimens,N-T specimens show a slower fatigue crack growth(FCG)rate in air,which can be attributed to crack closure effects and deformation twinning near the crack tip.The corrosion environment will not significantly change the main plastic deformation mechanisms for the same type of specimen.However,the FCG rate in phosphate buffer saline(PBS)is one order of magnitude higher than that in air,which is caused by the combined effects of hydrogen-induced cracking and anodic dissolution.Owing to the similar corrosion rates at crack tips,the specimens with different orientations display close FCG rates in PBS. 展开更多
关键词 Magnesium alloy orientATION CORROSION Fatigue crack growth
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Distributional and behavioral responses of the wintering Oriental Storks to drought in China’s largest freshwater lake
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作者 Fucheng Yang Mingqin Shao Jianying Wang 《Avian Research》 SCIE CSCD 2024年第2期187-195,共9页
Extreme droughts are increasing in frequency and severity globally as a result of climate change.Developing understanding of species’responses to drought is crucial for their conservation,especially in regions experi... Extreme droughts are increasing in frequency and severity globally as a result of climate change.Developing understanding of species’responses to drought is crucial for their conservation,especially in regions experi-encing increased aridity.Although numerous studies have investigated birds’responses to drought,the emphasis has primarily been on landbirds.Drought can significantly alter the wetland environments that waterbirds inhabit,but the response of waterbirds to drought remains understudied.In this study,we surveyed the distri-bution and behavior of Oriental Storks(Ciconia boyciana)in Poyang Lake,which is the largest freshwater lake in China.Results indicate that drought-induced catchment areas at the lowest water level limited the total popu-lation size of Oriental Storks in the sub-lakes.Sub-lakes with large catchment areas at the lowest water level demonstrated a capacity to support a larger population of wintering Oriental Storks.Over time,Oriental Storks exhibited a gradual concentration in Changhu Lake,characterized by larger catchments,after resource depletion in sub-lakes with smaller catchments.Additionally,the duration of Oriental Storks’vigilance and moving be-haviors decreased significantly compared with that observed before the drought.After the drought,Oriental Storks increased their foraging efforts,as evidenced by increased presence in deeper water and reaching their heads and necks into deeper water to forage,higher search rates,but lower foraging rates.In accordance with area-restricted search theory,reductions in habitat quality resulting from drought,including extensive fish die-offs,forced Oriental Storks to increase their foraging efforts.Sustaining a specific water area in sub-lakes during droughts can preserve resource availability,which is crucial for the conservation of Oriental Storks.Imple-menting measures such as water level control and micro-modification of lake bottoms in sub-lakes might mitigate the impact of drought on the piscivorous Oriental Storks. 展开更多
关键词 Climate change Extreme drought Foraging behavior oriental stork Poyang lake
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Effects of mesoclimate and microclimate variations mediated by high altitude and row orientation on sucrose metabolism and anthocyanin synthesis in grape berries
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作者 Haining Yin Zhaoxiang Wang +3 位作者 Lin Wang Jianhong Cao Jiakui Wang Zhumei Xi 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期713-731,共19页
Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with ... Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with this challenge.Stable,high-quality wine grape production may be achieved by synchronizing the meso-and microclimate.To clarify the role of high altitude and row orientation in meso-and microclimate and the response of berries to it,we evaluated seven years(2012-2018)of climate data,two years of basic grape(Cabernet Sauvignon,Vitis vinifera L.)quality,and one-year microclimate from veraison to harvest.By comparing two locations(Sidon 2047 m,Sinon 2208 m)in Yunnan Province,China,we found that the average temperature has been stable at approximately 15℃ for seven years,with no extreme weather or,noticeable global warming.The light intensity(LI)in the north-south(NS)was more balanced than the east-west(EW)direction,and the east-west to the south(EW-S)canopy side was almost higher than the other sides.High LI was associated with high photosynthetically active radiation(PAR),ultraviolet(UV),and infrared(IR)light and vice versa.The north-south to the east(NS-E)and east-west to the north(EWN)sides were characterized by lower LI and higher UV and IR light,and higher total anthocyanin content.Most anthocyanin synthesis-related genes,for example,VvF3'H and VvF3'5'H,were highly expressed in NS-E from veraison to maturity.Perhaps UV and IR light induced their expression.This study provides new insights on the role of differently orientated rows in controlling grape quality due to varied light quality.The findings are globally significant,particularly in the context of climate change,and offer fresh insights into berry physiological responses and decision-making for the management of existing vineyards. 展开更多
关键词 Vitis vinifera L. orientated rows Berry composition SUGAR PHENOLIC Light quality Solar radiation
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Alleviating the anisotropic microstructural change and boosting the lithium ions diffusion by grain orientation regulation for Ni-rich cathode materials
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作者 Xinyou He Shilin Su +3 位作者 Bao Zhang Zhiming Xiao Zibo Zhang Xing Ou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期213-222,I0005,共11页
Generally,layered Ni-rich cathode materials exhibit the morphology of polycrystalline secondary sphere composed of numerous primary particles.While the arrangement of primary particles plays a very important role in t... Generally,layered Ni-rich cathode materials exhibit the morphology of polycrystalline secondary sphere composed of numerous primary particles.While the arrangement of primary particles plays a very important role in the properties of Ni-rich cathodes.The disordered particle arrangement is harmful to the cyclic performance and structural stability,yet the fundamental understanding of disordered structure on the structural degradation behavior is unclarified.Herein,we have designed three kinds of LiNi_(0.83)Co_(0.06)Mn_(0.11)O_(2) cathode materials with different primary particle orientations by regulating the precursor coprecipitation process.Combining finite element simulation and in-situ characterization,the Li^(+)transport and structure evolution behaviors of different materials are unraveled.Specifically,the smooth Li^(+)diffusion minimizes the reaction heterogeneity,homogenizes the phase transition within grains,and mitigates the anisotropic microstructural change,thereby modulating the crack evolution behavior.Meanwhile,the optimized structure evolution ensures radial tight junctions of the primary particles,enabling enhanced Li^(+)diffusion during dynamic processes.Closed-loop bidirectional enhancement mechanism becomes critical for grain orientation regulation to stabilize the cyclic performance.This precursor engineering with particle orientation regulation provides the useful guidance for the structural design and feature enhancement of Ni-rich layered cathodes. 展开更多
关键词 Ni-rich cathode Grain orientation regulation Anisotropic microstructural change Precursor engineering Li~+-ions diffusion
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Estimation of cancer cell migration in biomimetic random/oriented collagen fiber microenvironments
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作者 姚静如 李国强 +8 位作者 姚喜耀 周连杰 叶志凯 刘艳平 郑栋天 唐婷 宋克纳 陈果 刘雳宇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期749-756,共8页
Increasing data indicate that cancer cell migration is regulated by extracellular matrixes and their surrounding biochemical microenvironment,playing a crucial role in pathological processes such as tumor invasion and... Increasing data indicate that cancer cell migration is regulated by extracellular matrixes and their surrounding biochemical microenvironment,playing a crucial role in pathological processes such as tumor invasion and metastasis.However,conventional two-dimensional cell culture and animal models have limitations in studying the influence of tumor microenvironment on cancer cell migration.Fortunately,the further development of microfluidic technology has provided solutions for the study of such questions.We utilize microfluidic chip to build a random collagen fiber microenvironment(RFM)model and an oriented collagen fiber microenvironment(OFM)model that resemble early stage and late stage breast cancer microenvironments,respectively.By combining cell culture,biochemical concentration gradient construction,and microscopic imaging techniques,we investigate the impact of different collagen fiber biochemical microenvironments on the migration of breast cancer MDA-MB-231-RFP cells.The results show that MDA-MB-231-RFP cells migrate further in the OFM model compared to the RFM model,with significant differences observed.Furthermore,we establish concentration gradients of the anticancer drug paclitaxel in both the RFM and OFM models and find that paclitaxel significantly inhibits the migration of MDA-MB-231-RFP cells in the RFM model,with stronger inhibition on the high concentration side compared to the low concentration side.However,the inhibitory effect of paclitaxel on the migration of MDA-MB-231-RFP cells in the OFM model is weak.These findings suggest that the oriented collagen fiber microenvironment resembling the late-stage tumor microenvironment is more favorable for cancer cell migration and that the effectiveness of anticancer drugs is diminished.The RFM and OFM models constructed in this study not only provide a platform for studying the mechanism of cancer development,but also serve as a tool for the initial measurement of drug screening. 展开更多
关键词 microfluidic chip random collagen fiber microenvironment(RFM) oriented collagen fiber microenvironment(OFM) cancer cell migration
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Analysis of the Effect of Problem-Oriented Nursing Intervention on Patients with Lower Extremity Arteriosclerosis Obliterans in Vascular Surgery
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作者 Yang An 《Journal of Clinical and Nursing Research》 2024年第4期1-6,共6页
Objective: To analyze the effect of problem-oriented nursing intervention on patients with lower extremity arteriosclerosis obliterans (ASO) in vascular surgery. Methods: The clinical data of 128 patients with lower e... Objective: To analyze the effect of problem-oriented nursing intervention on patients with lower extremity arteriosclerosis obliterans (ASO) in vascular surgery. Methods: The clinical data of 128 patients with lower extremity ASO in vascular surgery were selected and randomly divided into groups A and B, with 64 cases each. Group A is the control group, and Group B is the observation group. Group A received the routine nursing intervention, and Group B received the problem-oriented nursing intervention. The compliance, self-care ability, psychological state, quality of life, and nursing satisfaction of the two groups of patients were evaluated based on various indicators. Results: After the intervention, the evaluation of self-care ability (ESCA) score of the patients in Group B was higher than that of Group A, and the symptom checklist-90 (SCL-90) score was lower than that of Group A. The differences were significant (t = 10.019, t = 3.118, P < 0.01). After the intervention, the World Health Organization Quality of Life Brief (WHOQOL-BREF) index scores of the two groups increased and the increase in Group B was significantly higher than Group A (P < 0.001). The compliance rate of Group B (62/ 96.88%) was higher than that of Group A (52/ 81.25%), and the difference was extremely significant (χ2 = 8.020, P < 0.01). Conclusion: Problem-oriented nursing intervention for patients with lower extremity ASO in vascular surgery improved the patient’s self-care ability, and quality of life, reduced the patient’s negative emotions, and enhanced their overall satisfaction. 展开更多
关键词 Problem orientation Nursing intervention Vascular surgery Lower extremity arteriosclerosis obliterans
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An Approach to Detect Structural Development Defects in Object-Oriented Programs
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作者 Maxime Seraphin Gnagne Mouhamadou Dosso +1 位作者 Mamadou Diarra Souleymane Oumtanaga 《Open Journal of Applied Sciences》 2024年第2期494-510,共17页
Structural development defects essentially refer to code structure that violates object-oriented design principles. They make program maintenance challenging and deteriorate software quality over time. Various detecti... Structural development defects essentially refer to code structure that violates object-oriented design principles. They make program maintenance challenging and deteriorate software quality over time. Various detection approaches, ranging from traditional heuristic algorithms to machine learning methods, are used to identify these defects. Ensemble learning methods have strengthened the detection of these defects. However, existing approaches do not simultaneously exploit the capabilities of extracting relevant features from pre-trained models and the performance of neural networks for the classification task. Therefore, our goal has been to design a model that combines a pre-trained model to extract relevant features from code excerpts through transfer learning and a bagging method with a base estimator, a dense neural network, for defect classification. To achieve this, we composed multiple samples of the same size with replacements from the imbalanced dataset MLCQ1. For all the samples, we used the CodeT5-small variant to extract features and trained a bagging method with the neural network Roberta Classification Head to classify defects based on these features. We then compared this model to RandomForest, one of the ensemble methods that yields good results. Our experiments showed that the number of base estimators to use for bagging depends on the defect to be detected. Next, we observed that it was not necessary to use a data balancing technique with our model when the imbalance rate was 23%. Finally, for blob detection, RandomForest had a median MCC value of 0.36 compared to 0.12 for our method. However, our method was predominant in Long Method detection with a median MCC value of 0.53 compared to 0.42 for RandomForest. These results suggest that the performance of ensemble methods in detecting structural development defects is dependent on specific defects. 展开更多
关键词 Object-oriented Programming Structural Development Defect Detection Software Maintenance Pre-Trained Models Features Extraction BAGGING Neural Network
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Investigation Into the Market-Orientated New Product Development Performance 被引量:2
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作者 王秀村 卢彬彬 《Journal of Beijing Institute of Technology》 EI CAS 2007年第2期243-247,共5页
The effect that the market orientation brings to product innovation performance is reported and the degree of product innovativeness is explored. The interdepartmental integration inside the company is also investigat... The effect that the market orientation brings to product innovation performance is reported and the degree of product innovativeness is explored. The interdepartmental integration inside the company is also investigated. A series of hypotheses were developed aiming at presenting a conceptual framework to clarify how market orientation contributes to product innovation performance-moderated by the degree of product innovativeness and affected by the interdepartmental integration. Survey data from 36 business units were analyzed based on the respondents in the research. The statistic results suggest a substantial positive effect of market orientation on product innovation performance. Under the condition of incremental innovativeness among the samples, the more innovative the product is, the more improvements in product innovation performance would be achieved. A variety of particular interdepartmental integration mechanisms have been certified to lend more supports to establishing market orientation and improving product innovation performance. 展开更多
关键词 market orientation new product development (NPD) performance product innovativeness interdepartmental integration
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南美洲Oriente盆地斜坡带W区块构造-岩性复合油藏成藏模式及有利区预测
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作者 马文杰 王景春 +5 位作者 田作基 马中振 万学鹏 林金逞 许翔麟 周玉冰 《岩性油气藏》 CAS CSCD 北大核心 2023年第6期29-36,共8页
通过岩心观察、地震解释、储层反演、原油地化分析、油源对比、油气运移示踪分析等对南美洲Oriente盆地斜坡带W区块典型构造-岩性复合油藏的成藏规律进行了分析,并指出了下一步的有利勘探方向。研究结果表明:①Oriente盆地斜坡带W区块构... 通过岩心观察、地震解释、储层反演、原油地化分析、油源对比、油气运移示踪分析等对南美洲Oriente盆地斜坡带W区块典型构造-岩性复合油藏的成藏规律进行了分析,并指出了下一步的有利勘探方向。研究结果表明:①Oriente盆地斜坡带W区块构造-岩性复合油藏整体为西倾和西南倾单斜构造,局部发育鼻隆,油藏目的层为白垩系Napo组M1ss段,砂体呈北西—南东向,储层厚度大、物性好。②研究区河口湾砂坝控制有利储层分布,W区块平稳的西倾和西南倾单斜鼻隆构造背景与NW—SE走向的泥岩条带配合控制圈闭形成,有效油气运移通道的空间展布控制成藏。③构造-岩性油藏为三阶段成藏模式,早期常规原油充注,中期原油遭受降解,晚期常规原油混合降稠。④W区块南部地区2个泥岩条带的西南部位是W区块构造-岩性复合圈闭的有利发育区。 展开更多
关键词 构造-岩性复合油藏 成藏模式 斜坡带 白垩系 前陆盆地 oriente盆地 南美洲
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Microstructure evolution and passivation quality of hydrogenated amorphous silicon oxide(a-SiOx:H) on〈100〉- and 〈111〉-orientated c-Si wafers
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作者 陈俊帆 赵生盛 +8 位作者 延玲玲 任慧志 韩灿 张德坤 魏长春 王广才 侯国付 赵颖 张晓丹 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第3期480-487,共8页
Hydrogenated amorphous silicon oxide(a-SiOx:H) is an attractive passivation material to suppress epitaxial growth and reduce the parasitic absorption loss in silicon heterojunction(SHJ) solar cells. In this paper, a-S... Hydrogenated amorphous silicon oxide(a-SiOx:H) is an attractive passivation material to suppress epitaxial growth and reduce the parasitic absorption loss in silicon heterojunction(SHJ) solar cells. In this paper, a-SiOx:H layers on different orientated c-Si substrates are fabricated. An optimal effective lifetime(τ(eff)) of 4743 μs and corresponding implied opencircuit voltage(iV(oc)) of 724 mV are obtained on〈100〉-orientated c-Si wafers. While τ(eff) of 2429 μs and iV_(oc) of 699 mV are achieved on 111-orientated substrate. The FTIR and XPS results indicate that the a-SiOx:H network consists of SiOx(Si-rich), Si–OH, Si–O–SiHx, SiO2 ≡ Si–Si, and O3 ≡ Si–Si. A passivation evolution mechanism is proposed to explain the different passivation results on different c-Si wafers. By modulating the a-SiOx:H layer, the planar silicon heterojunction solar cell can achieve an efficiency of 18.15%. 展开更多
关键词 a-SiO_x:H orientated WAFERS silicon HETEROJUNCTION
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Crystallization and Orientation Modulation Enable Highly Efficient Doctor-Bladed Perovskite Solar Cells 被引量:2
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作者 Jianhui Chang Erming Feng +7 位作者 Hengyue Li Yang Ding Caoyu Long Yuanji Gao Yingguo Yang Chenyi Yi Zijian Zheng Junliang Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期40-52,共13页
With the rapid rise in perovskite solar cells(PSCs)performance,it is imperative to develop scalable fabrication techniques to accelerate potential commercialization.However,the power conversion efficiencies(PCEs)of PS... With the rapid rise in perovskite solar cells(PSCs)performance,it is imperative to develop scalable fabrication techniques to accelerate potential commercialization.However,the power conversion efficiencies(PCEs)of PSCs fabricated via scalable two-step sequential deposition lag far behind the state-of-the-art spin-coated ones.Herein,the additive methylammonium chloride(MACl)is introduced to modulate the crystallization and orientation of a two-step sequential doctorbladed perovskite film in ambient conditions.MACl can significantly improve perovskite film quality and increase grain size and crystallinity,thus decreasing trap density and suppressing nonradiative recombination.Meanwhile,MACl also promotes the preferred face-up orientation of the(100)plane of perovskite film,which is more conducive to the transport and collection of carriers,thereby significantly improving the fill factor.As a result,a champion PCE of 23.14%and excellent longterm stability are achieved for PSCs based on the structure of ITO/SnO_(2)/FA_(1-x)MA_xPb(I_(1-y)Br_y)_3/Spiro-OMeTAD/Ag.The superior PCEs of 21.20%and 17.54%are achieved for 1.03 cm~2 PSC and 10.93 cm~2 mini-module,respectively.These results represent substantial progress in large-scale two-step sequential deposition of high-performance PSCs for practical applications. 展开更多
关键词 Crystallization regulation orientation modulation Perovskite solar cells Doctor-blading Ambient condition
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Constructing an ion‐oriented channel on a zinc electrode through surface engineering 被引量:2
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作者 Xin Liu Kun Wang +6 位作者 Ying Liu Fuhua Zhao Jianjiang He Hao Wu Jianfei Wu Han‐Pu Liang Changshui Huang 《Carbon Energy》 SCIE EI CAS CSCD 2023年第11期2-14,共13页
The inherent shortcomings of a zinc anode in aqueous zinc‐ion batteries(ZIBs)such as zinc dendrites and side reactions severely limit their practical application.Herein,to address these issues,an ion‐oriented transp... The inherent shortcomings of a zinc anode in aqueous zinc‐ion batteries(ZIBs)such as zinc dendrites and side reactions severely limit their practical application.Herein,to address these issues,an ion‐oriented transport channel constructed by graphdiyne(GDY)nanowalls is designed and grown in situ on the surface of a zinc electrode.The vertically stacked GDY nanowalls with a unique hierarchical porous structure and mechanical properties form a nanomesh‐like interface on the zinc electrode,acting as an ion‐oriented channel,which can efficiently confine the segmented growth of zinc metal in microscopic regions of hundreds of nanometers.In those microscopic regions,the uniform domain current density is effortlessly maintained compared with a large surface area,thereby inhibiting zinc dendrites effectively.Besides,due to the presence of the ion‐oriented channel,the modified zinc anode demonstrates long‐term stable zinc plating/stripping performance for more than 600 h at 1 mAh cm^(−2)in an aqueous electrolyte.In addition,full‐cells coupled with MnO2 show high specific capacity and power density,as well as excellent cycling stability with a capacity retention of 82%after 5000 cycles at 1 A g^(−1).This work provides a feasible and accessible surface engineering approach to modify the electrode interface for confined and dendrite‐free zinc deposition in aqueous ZIBs. 展开更多
关键词 DENDRITE graphdiyne ion‐oriented channel nanomesh interface zinc‐ion batteries
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Flexible nest site selection of the endangered Oriental Storks(Ciconia boyciana):Trade-off from adaptive strategies 被引量:2
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作者 Lei Cheng Lizhi Zhou +2 位作者 Chao Yu Zhenhua Wei Chunhua Li 《Avian Research》 SCIE CSCD 2023年第2期242-249,共8页
Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selectio... Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selection can provide insights into how species adapt to changes in their habitat and has important conservation implications.In this study,we used microhabitat variables and multi-scale data with a field survey of nest occurrence to determine nest site selection patterns and adaptive strategies of the breeding Oriental Storks(Ciconia boyciana)in different nest areas.Results demonstrate that the nest site microhabitat characteristics of the breeding Oriental Storks significantly differed among the three nesting areas,and nest height was higher in the middle and lower Yangtze River floodplain than in the Northeast China and Bohai Bay nest areas.The food resources and intensity of human disturbance had the greatest effects on the nest site selection of the breeding Oriental Storks.The intensity of human disturbance was positively correlated with the nest height of the breeding Oriental Storks in Bohai Bay and the middle and lower Yangtze River floodplain;however,nest height decreased with the abundance of food resources in the Northeast China nest area.Our findings indicate that the nest site selection patterns of Oriental Storks showed flexible adaptive strategies.In safer environments,nests were lower and closer to food resources,which allows parent storks to invest more in the nestlings.However,in areas where human activity was intense,nests were higher to ensure the safety of their offspring.Some measures that could be taken to improve the breeding habitat of Oriental Storks include increasing the percentage of wetland areas in nesting areas to enhance food resources availability and setting artificial nests at suitable heights in potential nesting grounds to encourage nesting.Finally,the establishment of soft barriers around the nesting areas could increase the safety of nests. 展开更多
关键词 Adaptive strategies Breeding range expansion Habitat characteristics Nest site selection oriental storks
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Prediction of mechanical properties for deep drawing steel by deep learning 被引量:1
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作者 Gang Xu Jinshan He +2 位作者 Zhimin Lü Min Li Jinwu Xu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第1期156-165,共10页
At present,iron and steel enterprises mainly use“after spot test ward”to control final product quality.However,it is impossible to realize on-line quality predetermining for all products by this traditional approach... At present,iron and steel enterprises mainly use“after spot test ward”to control final product quality.However,it is impossible to realize on-line quality predetermining for all products by this traditional approach,hence claims and returns often occur,resulting in major eco-nomic losses of enterprises.In order to realize the on-line quality predetermining for steel products during manufacturing process,the predic-tion models of mechanical properties based on deep learning have been proposed in this work.First,the mechanical properties of deep drawing steels were predicted by using LSTM(long short team memory),GRU(gated recurrent unit)network,and GPR(Gaussian process regression)model,and prediction accuracy and learning efficiency for different models were also discussed.Then,on-line re-learning methods for transfer learning models and model parameters were proposed.The experimental results show that not only the prediction accuracy of optimized trans-fer learning models has been improved,but also predetermining time was shortened to meet real time requirements of on-line property prede-termining.The industrial production data of interstitial-free(IF)steel was used to demonstrate that R2 value of GRU model in training stage reaches more than 0.99,and R2 value in testing stage is more than 0.96. 展开更多
关键词 machine learning recurrent natural network transfer learning on-line prediction deep drawing steel mechanical properties
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Mutual impact of true triaxial stress, borehole orientation and bedding inclination on laboratory hydraulic fracturing of Lushan shale 被引量:1
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作者 Yongfa Zhang Anfa Long +2 位作者 Yu Zhao Arno Zang Chaolin Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第12期3131-3147,共17页
Unconventional resources like shale gas has been the focus of intense research and development for two decades. Apart from intrinsic geologic factors that control the gas shale productivity (e.g. organic matter conten... Unconventional resources like shale gas has been the focus of intense research and development for two decades. Apart from intrinsic geologic factors that control the gas shale productivity (e.g. organic matter content, bedding planes, natural fractures, porosity and stress regime among others), external factors like wellbore orientation and stimulation design play a role. In this study, we present a series of true triaxial hydraulic fracturing experiments conducted on Lushan shale to investigate the interplay of internal factors (bedding, natural fractures and in situ stress) and external factors (wellbore orientation) on the growth process of fracture networks in cubic specimens of 200 mm in length. We observe relatively low breakdown pressure and fracture propagation pressure as the wellbore orientation and/or the maximum in situ stress is subparallel to the shale bedding plane. The wellbore orientation has a more prominent effect on the breakdown pressure, but its effect is tapered with increasing angle of bedding inclination. The shale breakdown is followed by an abrupt response in sample displacement, which reflects the stimulated fracture volume. Based on fluid tracer analysis, the morphology of hydraulic fractures (HF) is divided into four categories. Among the categories, activation of bedding planes (bedding failure, BF) and natural fractures (NF) significantly increase bifurcation and fractured areas. Under the same stress regime, a horizontal wellbore is more favorable to enhance the complexity of hydraulic fracture networks. This is attributed to the relatively large surface area in contact with the bedding plane for the horizontal borehole compared to the case with a vertical wellbore. These findings provide important references for hydraulic fracturing design in shale reservoirs. 展开更多
关键词 True triaxial hydraulic fracturing experiment In situ stress state Bedding planes Natural fractures Wellbore orientation Shale reservoirs
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Construction of Oriented Structure in Inner Surface of Small-Diameter Artificial Blood Vessels:A Review 被引量:1
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作者 伊光辉 成馨雨 +3 位作者 耿梦想 孟凯 张克勤 赵荟菁 《Journal of Donghua University(English Edition)》 CAS 2023年第2期149-163,共15页
There is an urgent need for small-diameter artificial blood vessels in clinic.Physical,chemical and biological factors should be integrated to avoid thrombosis and intimal hyperplasia after implantation and to promote... There is an urgent need for small-diameter artificial blood vessels in clinic.Physical,chemical and biological factors should be integrated to avoid thrombosis and intimal hyperplasia after implantation and to promote successful fabrication of small-diameter artificial blood vessels.From a physical perspective,the internal oriented structures of natural blood vessels plays an important role in guiding the directional growth of cells,improving the blood flow environment,and promoting the regeneration of vascular tissue.In this review,the effects of the oriented structures on cells,including endothelial cells(ECs),smooth muscle cells(SMCs)and stem cells,as well as the effect of the oriented structures on hemodynamics and vascular tissue remodeling and regeneration are introduced.Various forms of oriented structures(fibers,grooves,channels,etc.)and their construction methods are also reviewed.Conclusions and future perspectives are given.It is expected to give some references to relevant researches. 展开更多
关键词 small-diameter artificial blood vessel internal oriented structure direct cell behavior vascular tissue remodeling and regeneration
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Research on the Drawing-up of the Pole Figure for Orientation Analysis of Directional Si Steel Sheet
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作者 S.H. O (Kim Chaek University of Technology, Kyogu Dong, Central District, Pyongyang, D.P.R. of Korea) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第2期159-160,共2页
The magnetic property of soft magnetic metals and alloys depends strongly on the crystallo-graphic orientation. In automated equipment for orientation research, the intensity for drawing up the pole figure is measured... The magnetic property of soft magnetic metals and alloys depends strongly on the crystallo-graphic orientation. In automated equipment for orientation research, the intensity for drawing up the pole figure is measured in detail. The present research shows that the accurate pole figure can be drawn up without measuring concretely the intensity. For directional Si steel sheet the measuring step may be 4~5 degrees. In this paper the experimental equation for defo-cusing correction was derived from the experimental data in different specimens with random orientation. 展开更多
关键词 FIGURE Research on the drawing-up of the Pole Figure for orientation Analysis of Directional Si Steel Sheet SI
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Impact of orientation of blast initiation on ground vibrations
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作者 Dayamoy Garai Hemant Agrawal Arvind Kumar Mishra 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第1期255-261,共7页
The blast-induced ground vibrations can be significantly controlled by varying the location and orien-tation of point of interest from blast site.The blast waves generated due to individual holes get super-imposed and... The blast-induced ground vibrations can be significantly controlled by varying the location and orien-tation of point of interest from blast site.The blast waves generated due to individual holes get super-imposed and resultant peak particle velocity(PPV)generates.With the orientation sequence of holes blasts on site,the superimposition angle of wave changes and hence results in significant variation in resultant PPV.The orientation with respect to the initiation of blasts resulting in lowest PPV needs to be identified for any site.By knowing the PPV contour of vibration waves in mine sites,it is possible to reduce the vibration on the structures by changing the initiation sequence.In this paper,experimental blasts were conducted at two different mine sites and the PPV values were recorded at different ori-entations from the blast site and its initiation sequence.The PPV contours were drawn to identify the orientation with least and highest PPV generation line.It was found that by merely changing the initi-ation sequence of blasts with respect to the sensitive structure or point of interest,the PPV values can be reduced significantly up to 76.9%. 展开更多
关键词 Peak particle velocity(PPV) Initiation orientation Wave superimposition orientation of blast Blast initiation
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