期刊文献+
共找到1,951篇文章
< 1 2 98 >
每页显示 20 50 100
Oriental Utopia under the Gaze of the Other-A Brief Analysis of the Construction of the Oriental Image in Lost Horizon
1
作者 ZHU Shuang-jie 《Journal of Literature and Art Studies》 2023年第5期340-346,共7页
Lost Horizon tells a story about Shangri-La,a paradise in the Orient.Throughout the construction of the Oriental image in the novel,it can be found that under its representation of being enslaved,driven,marginalized a... Lost Horizon tells a story about Shangri-La,a paradise in the Orient.Throughout the construction of the Oriental image in the novel,it can be found that under its representation of being enslaved,driven,marginalized and silenced,it implies a three-dimensional flow mechanism with multiple power-relationships interwoven between Orient and Occident,insiders and outsiders,“civilized”and“uncivilized”,male and female,etc.Driven by this mechanism,the Oriental image is integrated under a single abstract label,which has become a way for the Occident to re-understand,reconstruct and express itself after the war. 展开更多
关键词 Lost Horizon “the other ORIENTALISM oriental image
下载PDF
一种改进Oriented RepPoints的遥感图像有向目标检测
2
作者 谢国波 张家源 +1 位作者 林志毅 廖文康 《小型微型计算机系统》 CSCD 北大核心 2024年第11期2725-2731,共7页
为解决Oriented RepPoints算法在遥感图像有向目标检测中因遥感图像背景干扰信息较多和目标尺度大小不一所导致的检测精度不高、易漏检误检等问题,提出一种改进Oriented RepPoints的遥感图像有向目标检测方法MA-RPDet(Mixed Attention R... 为解决Oriented RepPoints算法在遥感图像有向目标检测中因遥感图像背景干扰信息较多和目标尺度大小不一所导致的检测精度不高、易漏检误检等问题,提出一种改进Oriented RepPoints的遥感图像有向目标检测方法MA-RPDet(Mixed Attention RepPoints Detector).首先,采用了PVTv2作为主干网络,该网络利用线性空间缩减自注意力机制提取出更具局部连续性的特征图,并保持与卷积运算类似的线性复杂度.其次,在特征融合阶段设计了串联性混合注意力模块,进一步强化了重要特征,促进了多尺度特征的高效交互.最后,引入平滑GIoU损失函数对模型学习策略进行优化,提高了检测精度.在两个遥感图像目标检测数据集DOTA和HRSC2016上的实验结果表明,所提方法的检测精度mAP分别达到了77.19%和90.3%,均高于其他对比算法,证明了本文方法的有效性. 展开更多
关键词 遥感图像 有向目标检测 Oriented RepPoints 注意力机制 损失函数
下载PDF
基于改进Oriented R-CNN的旋转框麦穗检测与计数模型 被引量:1
3
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
下载PDF
厄瓜多尔Oriente盆地白垩系Napo组LU亚段沉积模式
4
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
下载PDF
In Situ Deposition of Drug and Gene Nanoparticles on a Patterned Supramolecular Hydrogel to Construct a Directionally Osteochondral Plug 被引量:1
5
作者 Jiawei Kang Yaping Li +7 位作者 Yating Qin Zhongming Huang Yifan Wu Long Sun Cong Wang Wei Wang Gang Feng Yiying Qi 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期341-359,共19页
The integrated repair of bone and cartilage boasts advantages for osteochondral restoration such as a long-term repair effect and less deterioration compared to repairing cartilage alone.Constructing multifactorial,sp... The integrated repair of bone and cartilage boasts advantages for osteochondral restoration such as a long-term repair effect and less deterioration compared to repairing cartilage alone.Constructing multifactorial,spatially oriented scaffolds to stimulate osteochondral regeneration,has immense significance.Herein,targeted drugs,namely kartogenin@polydopamine(KGN@PDA)nanoparticles for cartilage repair and miRNA@calcium phosphate(miRNA@CaP)NPs for bone regeneration,were in situ deposited on a patterned supramolecular-assembled 2-ureido-4[lH]-pyrimidinone(UPy)modified gelation hydrogel film,facilitated by the dynamic and responsive coordination and complexation of metal ions and their ligands.This hydrogel film can be rolled into a cylindrical plug,mimicking the Haversian canal structure of natural bone.The resultant hydrogel demonstrates stable mechanical properties,a self-healing ability,a high capability for reactive oxygen species capture,and controlled release of KGN and miR-26a.In vitro,KGN@PDA and miRNA@CaP promote chondrogenic and osteogenic differentiation of mesenchymal stem cells via the JNK/RUNX1 and GSK-3β/β-catenin pathways,respectively.In vivo,the osteochondral plug exhibits optimal subchondral bone and cartilage regeneration,evidenced by a significant increase in glycosaminoglycan and collagen accumulation in specific zones,along with the successful integration of neocartilage with subchondral bone.This biomaterial delivery approach represents a significant toward improved osteochondral repair. 展开更多
关键词 Osteochondral regeneration Oriented hydrogel Kartogenin miRNA-26a
下载PDF
Hepatolithiasis:Epidemiology,presentation,classification and management of a complex disease 被引量:1
6
作者 Rodrigo V.Motta Francesca Saffioti Vasileios K Mavroeidis 《World Journal of Gastroenterology》 SCIE CAS 2024年第13期1836-1850,共15页
The term hepatolithiasis describes the presence of biliary stones within the intrahepatic bile ducts,above the hilar confluence of the hepatic ducts.The disease is more prevalent in Asia,mainly owing to socioeconomic ... The term hepatolithiasis describes the presence of biliary stones within the intrahepatic bile ducts,above the hilar confluence of the hepatic ducts.The disease is more prevalent in Asia,mainly owing to socioeconomic and dietary factors,as well as the prevalence of biliary parasites.In the last century,owing to migration,its global incidence has increased.The main pathophysiological mechanisms involve cholangitis,bile infection and biliary strictures,creating a self-sustaining cycle that perpetuates the disease,frequently characterised by recurrent episodes of bacterial infection referred to as syndrome of“recurrent pyogenic cholangitis”.Furthermore,long-standing hepatolithiasis is a known risk factor for development of intrahepatic cholangiocarcinoma.Various classifications have aimed at providing useful insight of clinically relevant aspects and guidance for treatment.The management of symptomatic patients and those with complications can be complex,and relies upon a multidisciplinary team of hepatologists,endoscopists,interventional radiologists and hepatobiliary surgeons,with the main goal being to offer relief from the clinical presentations and prevent the development of more serious complications.This comprehensive review provides insight on various aspects of hepatolithiasis,with a focus on epidemiology,new evidence on pathophysiology,most important clinical aspects,different classification systems and contemporary management. 展开更多
关键词 CHOLELITHIASIS Intrahepatic stones Cholangiocarcinoma Biliary parasites Recurrent pyogenic cholangitis Oriental cholangiohepatitis Hepatectomy CHOLANGIOSCOPY Liver transplant PAEDIATRIC
下载PDF
Accelerated Sequential Deposition Reaction via Crystal Orientation Engineering for Low-Temperature,High-Efficiency Carbon-Electrode CsPbBr_(3) Solar Cells 被引量:1
7
作者 Zeyang Zhang Weidong Zhu +10 位作者 Tianjiao Han Tianran Wang Wenming Chai Jiaduo Zhu He Xi Dazheng Chen Gang Lu Peng Dong Jincheng Zhang Chunfu Zhang Yue Hao 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期168-175,共8页
Low-temperature,ambient processing of high-quality CsPbBr_(3)films is demanded for scalable production of efficient,low-cost carbon-electrode perovskite solar cells(PSCs).Herein,we demonstrate a crystal orientation en... Low-temperature,ambient processing of high-quality CsPbBr_(3)films is demanded for scalable production of efficient,low-cost carbon-electrode perovskite solar cells(PSCs).Herein,we demonstrate a crystal orientation engineering strategy of PbBr_(2)precursor film to accelerate its reaction with CsBr precursor during two-step sequential deposition of CsPbBr_(3)films.Such a novel strategy is proceeded by adding CsBr species into PbBr_(2)precursor,which can tailor the preferred crystal orientation of PbBr_(2)film from[020]into[031],with CsBr additive staying in the film as CsPb_(2)Br_(5)phase.Theoretical calculations show that the reaction energy barrier of(031)planes of PbBr_(2)with CsBr is lower about 2.28 eV than that of(O2O)planes.Therefore,CsPbBr_(3)films with full coverage,high purity,high crystallinity,micro-sized grains can be obtained at a low temperature of 150℃.Carbon-electrode PSCs with these desired CsPbBr_(3)films yield the record-high efficiency of 10.27%coupled with excellent operation stability.Meanwhile,the 1 cm^(2)area one with the superior efficiency of 8.00%as well as the flexible one with the champion efficiency of 8.27%and excellent mechanical bending characteristics are also achieved. 展开更多
关键词 carbon-electrode perovskite solar cells crystal orientation engineering CsPbBr_(3) low temperature two-step sequential deposition
下载PDF
Three-dimensionally oriented organization of hexagonal MIL-96 microplates toward superior film microstructure
8
作者 Sixing Chen Xinmiao Jin +3 位作者 Yuyang Wu Taotao Ji Fei Wang Yi Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期69-73,共5页
Preferential orientation control of metal—organic framework(MOF)films is advantageous for maximizing pore uniformity and minimizing grain-boundary defects.Nonetheless,the preparation of MOF films with both in-plane a... Preferential orientation control of metal—organic framework(MOF)films is advantageous for maximizing pore uniformity and minimizing grain-boundary defects.Nonetheless,the preparation of MOF films with both in-plane and out-of-plane orientations remains a grand challenge.In this study,we reported the preparation of three-dimensionally oriented MIL-96 layers through combining morphology control of MIL-96 seeds with addition of polyvinylpyrrolidone surfactants and arachidonic acids.The three-dimensionally oriented MIL-96 film was readily obtained through in-plane epitaxial growth.It is anticipated that the aforementioned protocol can be effective for obtaining diverse MOF films with a three-dimensionally oriented organization. 展开更多
关键词 Metaleorganic framework FILM Orientation Epitaxial growth Morphological control
下载PDF
Manipulating Crystal Growth and Secondary Phase PbI_(2)to Enable Efficient and Stable Perovskite Solar Cells with Natural Additives
9
作者 Yirong Wang Yaohui Cheng +5 位作者 Chunchun Yin Jinming Zhang Jingxuan You Jizheng Wang Jinfeng Wang Jun Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期432-448,共17页
In perovskite solar cells(PSCs),the inherent defects of perovskite film and the random distribution of excess lead iodide(PbI_(2))prevent the improvement of efficiency and stability.Herein,natural cellulose is used as... In perovskite solar cells(PSCs),the inherent defects of perovskite film and the random distribution of excess lead iodide(PbI_(2))prevent the improvement of efficiency and stability.Herein,natural cellulose is used as the raw material to design a series of cellulose derivatives for perovskite crystallization engineering.The cationic cellulose derivative C-Im-CN with cyano-imidazolium(Im-CN)cation and chloride anion prominently promotes the crystallization process,grain growth,and directional orientation of perovskite.Meanwhile,excess PbI_(2)is transferred to the surface of perovskite grains or formed plate-like crystallites in local domains.These effects result in suppressing defect formation,decreasing grain boundaries,enhancing carrier extraction,inhibiting non-radiative recombination,and dramatically prolonging carrier lifetimes.Thus,the PSCs exhibit a high power conversion efficiency of 24.71%.Moreover,C-Im-CN has multiple interaction sites and polymer skeleton,so the unencapsulated PSCs maintain above 91.3%of their initial efficiencies after 3000 h of continuous operation in a conventional air atmosphere and have good stability under high humidity conditions.The utilization of biopolymers with excellent structure-designability to manage the perovskite opens a state-of-the-art avenue for manufacturing and improving PSCs. 展开更多
关键词 PEROVSKITE Solar cells Defect passivation Biomass additives Crystal orientation
下载PDF
A new rhombohedral phase and its 48 variants inβtitanium alloy
10
作者 Xin-nan WANG Ming HAN +2 位作者 Fu-rong ZHANG Guang-ming ZHAO Zhi-shou ZHU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2849-2863,共15页
A new rhombohedral phase(termed R′)in a solution-aging-treated titanium alloy(Ti-4.5Al-6.5Mo-2Cr-2Nb-1V-1Sn-1Zr,wt.%)was identified.Its accurate Bravais lattice parameters were determined by a novel unit cell reconst... A new rhombohedral phase(termed R′)in a solution-aging-treated titanium alloy(Ti-4.5Al-6.5Mo-2Cr-2Nb-1V-1Sn-1Zr,wt.%)was identified.Its accurate Bravais lattice parameters were determined by a novel unit cell reconstruction method based on conventional selected-area electron diffraction(SAED)technique.The orientation relationship between R'phase and BCC phase was revealed.The results show that the R′phase is found to have 48crystallographically equivalent variants,resulting in rather complicated SAED patterns with high-order reflections.A series of in-situ SAED patterns were taken along both low-and high-index zone axes,and all weak and strong reflections arising from the 48 variants were properly explained and directly assigned with self-consistent Miller indices,confirming the presence of the rhombohedral phase.Additionally,some criteria were also proposed for evaluating the indexed results,which together with the Bravais lattice reconstruction method shed light on the microstructure characterization of even unknown phases in other alloys. 展开更多
关键词 titanium alloy rhombohedral phase Bravais lattice reconstruction VARIANT orientation relationship
下载PDF
Effects of orientation on the fatigue crack growth behaviors of the ZK60 magnesium alloy in air and PBS
11
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
下载PDF
Effects of pressure relief holes on coal burst:Insights from true-triaxial unloading tests
12
作者 Fuqiang Ren Murat Karakus +1 位作者 Giang Nguyen Thomas Bruning 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3378-3394,共17页
Drilling pressure relief is one of the methods to reduce the risk of coal bursts in deep mines.However,the effect of the drill hole orientations has not been studied well enough to understand their impact on the burst... Drilling pressure relief is one of the methods to reduce the risk of coal bursts in deep mines.However,the effect of the drill hole orientations has not been studied well enough to understand their impact on the burst failure mechanism.In this study,we investigated two designs of drill hole orientations.The first design includes drill holes located on the upper free face of the rectangular samples and labelled as upper hole(UH)and centre hole(CH)e the long axes of the drill holes are aligned with minor principal stress,s3,direction.The second design includes drill holes at the top(TH)and the side(SH)of the rectangular samples in which the long axes of the drill holes are aligned with the maximum,s1,and intermediate principal stress,s2,directions,respectively.The coal samples with the proposed drill hole orientations were subjected to the true-triaxial unloading coal burst tests.The results show that the drill holes reduce the risk of coal bursts.However,we found that the intensity of coal burst was significantly reduced with the SH-type,followed by the CH-types.We also observed that the coal burst intensity is reduced better for the CH,UH,TH,and SH-type drilling patterns.However,it was found that the orientations of drill holes have little influence on the failure mode(splitting).The acoustic emission(AE)activities for coal with drill holes noticeably decreased,especially for the UH and CH layouts.The drill holes reduced the upper limit of the AE entropy(chaos of microcracks generation).However,regarding reducing the coal burst risk,the TH and SH are less effective than UH and CH. 展开更多
关键词 Coal burst Triaxial unloading Drilling orientation Ejection characteristic Acoustic emission(AE)
下载PDF
Distributional and behavioral responses of the wintering Oriental Storks to drought in China’s largest freshwater lake
13
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
下载PDF
Transfer film effects induced by 3D-printed polyether-ether-ketone with excellent tribological properties for joint prosthesis
14
作者 Yang Li Jibao Zheng +1 位作者 Changning Sun Dichen Li 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第1期43-56,共14页
Based on the building principle of additive manufacturing,printing orientation mainly determines the tribological properties of joint prostheses.In this study,we created a polyether-ether-ketone(PEEK)joint prosthesis ... Based on the building principle of additive manufacturing,printing orientation mainly determines the tribological properties of joint prostheses.In this study,we created a polyether-ether-ketone(PEEK)joint prosthesis using fused filament fabrication and investigated the effects of printing orientation on its tribological properties using a pin-on-plate tribometer in 25% newborn calf serum.An ultrahigh molecular weight polyethylene transfer film is formed on the surface of PEEK due to the mechanical capture of wear debris by the 3D-printed groove morphology,which is significantly impacted by the printing orientation of PEEK.When the printing orientation was parallel to the sliding direction of friction,the number and size of the transfer film increased due to higher steady stress.This transfer film protected the matrix and reduced the friction coefficient and wear rate of friction pairs by 39.13%and 74.33%,respectively.Furthermore,our findings provide a novel perspective regarding the role of printing orientation in designing knee prostheses,facilitating its practical applications. 展开更多
关键词 3D printing orientation Transfer film Tribological properties Polyether-ether-ketone Knee prosthesis
下载PDF
Effects of mesoclimate and microclimate variations mediated by high altitude and row orientation on sucrose metabolism and anthocyanin synthesis in grape berries
15
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
下载PDF
Relationship between self-propelled velocity and Brownian motion for spherical and ellipsoid particles
16
作者 Jingwen Wang Ming Xu Deming Nie 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期305-311,共7页
The Brownian motion of spherical and ellipsoidal self-propelled particles was simulated without considering the effect of inertia and using the Langevin equation and the diffusion coefficient of ellipsoidal particles ... The Brownian motion of spherical and ellipsoidal self-propelled particles was simulated without considering the effect of inertia and using the Langevin equation and the diffusion coefficient of ellipsoidal particles derived by Perrin.The P´eclet number(Pe)was introduced to measure the relative strengths of self-propelled and Brownian motions.We found that the motion state of spherical and ellipsoid self-propelled particles changed significantly under the influence of Brownian motion.For spherical particles,there were three primary states of motion:1)when Pe<30,the particles were still significantly affected by Brownian motion;2)when Pe>30,the self-propelled velocities of the particles were increasing;and 3)when Pe>100,the particles were completely controlled by the self-propelled velocities and the Brownian motion was suppressed.In the simulation of the ellipsoidal self-propelled particles,we found that the larger the aspect ratio of the particles,the more susceptible they were to the influence of Brownian motion.In addition,the value interval of Pe depended on the aspect ratio.Finally,we found that the directional motion ability of the ellipsoidal self-propelled particles was much weaker than that of the spherical self-propelled particles. 展开更多
关键词 Brown motion self-propelled particle orientation movement
下载PDF
Alleviating the anisotropic microstructural change and boosting the lithium ions diffusion by grain orientation regulation for Ni-rich cathode materials
17
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
下载PDF
Oriental Reed Warblers do not abandon Common Cuckoo chicks during prolonged nestling periods
18
作者 Hanlin Yan Huahua Zhao +3 位作者 Haixia Luo Longwu Wang Laikun Ma Wei Liang 《Avian Research》 SCIE CSCD 2024年第3期369-373,共5页
The Oriental Reed Warbler(Acrocephalus orientalis)is one of the most commonly used hosts for the parasitic Common Cuckoo(Cuculus canorus).However,as hosts that feed unrelated parasitic nestlings may suffer extra repro... The Oriental Reed Warbler(Acrocephalus orientalis)is one of the most commonly used hosts for the parasitic Common Cuckoo(Cuculus canorus).However,as hosts that feed unrelated parasitic nestlings may suffer extra reproductive costs,they may be less willing to care for nestlings that have prolonged nestling periods.To test this hypothesis,the duration of feeding by Oriental Reed Warblers under natural conditions for their own nestlings was compared with the duration of feeding under natural conditions for Common Cuckoo nestlings and for artificially prolonged cuckoo nestlings.The results showed that Oriental Reed Warblers did not starve,drive away,or desert any of the nestlings in the experiment,and neither parent was left alone.Our experimental study indicates that both Oriental Reed Warbler parents were willing to care for nestlings with a prolonged nestling period(up to 30 days,twice the average duration time that the Oriental Reed Warblers fed their own chicks in natural conditions).However,further experiments and observations are required in other host bird species to examine whether both parents or one of the parents may exhibit the behavior of abandoning nestlings with a prolonged nestling period. 展开更多
关键词 Brood parasitism Common Cuckoo Deserted nestling Oriental Reed Warbler Prolonged nestling period
下载PDF
Effect of Lewis acid-base additive on lead-free Cs_(2)SnI_(6) thin film prepared by direct solution coating process
19
作者 Saqib Nawaz Khan 王燕 +3 位作者 钟李祥 梁会力 杜小龙 梅增霞 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期444-451,共8页
Inorganic Cs_(2)SnI_(6) perovskite has exhibited substantial potential for light harvesting due to its exceptional optoelectronic properties and remarkable stability in ambient conditions.The charge transport characte... Inorganic Cs_(2)SnI_(6) perovskite has exhibited substantial potential for light harvesting due to its exceptional optoelectronic properties and remarkable stability in ambient conditions.The charge transport characteristics within perovskite films are subject to modulation by various factors,including crystalline orientation,morphology,and crystalline quality.Achieving preferred crystalline orientation and film morphology via a solution-based process is challenging for Cs_(2)SnI_(6) films.In this work,we employed thiourea as an additive to optimize crystal orientation,enhance film morphology,promote crystallization,and achieve phase purity.Thiourea lowers the surface energy of the(222)plane along the(111)direction,confirmed by x-ray diffraction,x-ray photoelectron spectroscopy,ultraviolet photoelectron spectroscopy studies,and density functional theory calculations.Varying thiourea concentration enables a bandgap tuning of Cs_(2)SnI_(6) from 1.52 eV to1.07 eV.This approach provides a novel method for utilizing Cs_(2)SnI_(6) films in high-performance optoelectronic devices. 展开更多
关键词 Cs_(2)SnI_(6) crystalline orientation Lewis acid-case additive engineering bandgap engineering
下载PDF
Laser-Constructing 3D Copper Current Collector with Crystalline Orientation Selectivity for Stable Lithium Metal Batteries
20
作者 Hui Li Gang Wang +3 位作者 Jin Hu Jun Li Jiaxu Huang Shaolin Xu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期129-139,共11页
The practical application of lithium(Li)metal anodes in high-capacity batteries is impeded by the formation of hazardous Li dendrites.To address this challenge,this research presents a novel methodology that combines ... The practical application of lithium(Li)metal anodes in high-capacity batteries is impeded by the formation of hazardous Li dendrites.To address this challenge,this research presents a novel methodology that combines laser ablation and heat treatment to precisely induce controlled grain growth within laser-structured grooves on copper(Cu)current collectors.Specifically,this approach enhances the prevalence of Cu(100)facets within the grooves,effectively lowering the overpotential for Li nucleation and promoting preferential Li deposition.Unlike approaches that modify the entire surface of collectors,our work focuses on selectively enhancing lithiophilicity within the grooves to mitigate the formation of Li dendrites and exhibit exceptional performance metrics.The half-cell with these collectors maintains a remarkable Coulombic efficiency of 97.42%over 350 cycles at 1 mA cm^(−2).The symmetric cell can cycle stably for 1600 h at 0.5 mA cm^(−2).Furthermore,when integrated with LiFePO4 cathodes,the full-cell configuration demonstrates outstanding capacity retention of 92.39%after 400 cycles at a 1C discharge rate.This study introduces a novel technique for fabricating selective lithiophilic three-dimensional(3D)Cu current collectors,thereby enhancing the performance of Li metal batteries.The insights gained from this approach hold promise for enhancing the performance of all laser-processed 3D Cu current collectors by enabling precise lithiophilic modifications within complex structures. 展开更多
关键词 copper current collector heat treatment laser processing lithium metal battery selective crystalline orientation
下载PDF
上一页 1 2 98 下一页 到第
使用帮助 返回顶部