检索结果-南通市图书馆

The effect of artificial solar spectrum on growth of cucumber and lettuce under controlled environment

Journal of Integrative Agriculture 2020年第8期19卷 2027-2034页

作者： ZOU Jie zhou Cheng-bo XU Hong CHENG Rui-feng YANG Qi-chang LI Tao Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Sonneteck Technology Co. Ltd.Xiamen 361000P.R.China

Light-emitting diodes(LEDs)have been widely applied in the controlled environment agriculture,which are characterized by relatively narrow-band spectra and energetical *** recently,the spectrum of Sunlike LEDs has been engineered and it closely resembles solar spectrum in the range of photosynthetic active radiation(PAR,400–700 nm).To investigate how plant growth responses to the spectrum of Sunlike LEDs,cucumber and lettuce plants were cultivated and their responses were compared with the conventional white LEDs as well as composite of red and blue LEDs(RB,R/B ratio was 9:1).We observed that although Sunlike LEDs resulted in a longer stem in cucumber,dry weight and leaf area were similar as those under RB LEDs,and significantly higher than those under white ***,cucumber leaves grown under Sunlike and white LEDs showed higher photosynthetic capacity than those grown under RB *** lettuce,plants grown under Sunlike LEDs showed larger leaf area and higher dry weight than the other two ***,the leaf photosynthetic capacity of lettuce grown under Sunlike LEDs was the *** this context,the spectrum induced plant functions are ***,the three types of LEDs show distinct light spectra and they are different in many ***,it is difficult to attribute the different plant responses to certain specific light *** conclude that plants grown under Sunlike LEDs exhibit larger leaf area,which may be due to some specific spectrum distributions(such as more far-red radiation),and consequently are favorable for light interception and therefore result in greater production.

关键词： cucumber leaf photosynthesis lettuce plant morphology Sunlike LEDs

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A proposal on complementary determination of the effective electro-weak mixing angles via doubly heavy-flavored hadron production at a super Z-factory

引用

Science China(Physics,Mechanics & Astronomy) 2020年第8期63卷 61-70页

作者： Xu-chang Zheng Chao-Hsi chang Tai-Fu feng Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics Chongqing UniversityChongqing 401331China China Center of Advanced Science and Technology(CCAST)(World Laboratory) Beijing 100190China Department of Physics Hebei UniversityBaoding 071002China

To test the standard model(SM)precisely and to look for the clues deviating from SM,a proposal for determining the effective electro-weak mixing angles sin2θefff(particularly f=lept,c,b)is *** is via observing the asymmetries(the forward-backward one AFB,the left-right one ALR and the combined left-right forward-backward one ALRFB)of the doubly heavy-flavored hadrons in the production at a super Z-factory(an e+e-collider designed with a luminosity as high as possible for modernday techniques runs around the center-of-mass energy s1/2=mZ).To see the sensitivity,uncertainties as well as the event accumulation precisely,the observables for describing the asymmetries of the produced hadrons are computed numerically with varying effective mixing angles,and based on the result analyses,it is concluded that the proposal may offer an independent complement determination of the effective mixing angles.

关键词： electro-weak mixing angle production of doubly heavy-flavored hadron asymmetries super Z-factory

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

制动盘自由模态仿真与试验对比及模态置信度研究

引用

山东科学 2021年第6期34卷 106-111页

作者：周长峰张家豪刘立邦刘新磊王希波山东交通学院汽车工程学院山东济南250357

建立了制动盘有限元模型,仿真得到制动盘前五阶弹性模态;对制动盘进行模态试验,阐述了制动盘模态试验的参数选择、测点布置、模态置信度判断准则,并通过综合频率响应函数和模态置信准则验证了试验结果的可靠性;仿真与试验得到的制动盘... 详细信息

建立了制动盘有限元模型,仿真得到制动盘前五阶弹性模态;对制动盘进行模态试验,阐述了制动盘模态试验的参数选择、测点布置、模态置信度判断准则,并通过综合频率响应函数和模态置信准则验证了试验结果的可靠性;仿真与试验得到的制动盘模态振型、模态频率等结果误差很小,二者基本一致。结果表明,所建立的制动盘有限元模型可用于约束状态下制动盘振动和噪声性能的预测。

关键词：制动盘弹性模态模态分析仿真

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Numerical Simulation and Experimental Study on Interlock Deformation for Roll Formed U-Section Steel Piling

引用

Journal of Iron and Steel Research International 2013年第11期20卷 41-45页

作者： feng Guang-hong ZHANG Pei ZHANG Hong-liang zhou Xu-chang ZHAO Yong Metallurgical Technology Institute Central Iron and Steel Research Institute Taian Kenuo Profile Steel Co. Ltd.

The interlock of a roll formed U-section sheet steel piling under loading was analyzed by means of numeri- cal simulation, and meanwhile the tensile failure experiment was conducted. The results indicated that under the same load, the interlock corners of roll formed steel piling are not only the regions with the lowest safety factor, but also the regions with the highest stress; there are two slippages in the tensile instability process of interlock, Each slippage can be regarded as a failure, and different types of failure mode should be used to evaluate the performance of steel pilings according to different applications. Due to the work hardening effect during the roll forming process, the hardness of the interlock material increases by 16% compared with that of the original sheet steel. It was also found that the instability strength obtained in tensile failure test is only 15.6 % of the tensile strength of the original sheet steel.

关键词： roll formed sheet steel piling interlock numerical simulation instability

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Deep forest

引用

National Science Review 2019年第1期6卷 74-86页

作者： Zhi-Hua zhou Ji feng National Key Laboratory for Novel Software Technology Nanjing University

Current deep-learning models are mostly built upon neural networks, i.e. multiple layers of parameterized differentiable non-linear modules that can be trained by backpropagation. In this paper, we explore the possibility of building deep models based on non-differentiable modules such as decision trees. After a discussion about the mystery behind deep neural networks, particularly by contrasting them with shallow neural networks and traditional machine-learning techniques such as decision trees and boosting machines,we conjecture that the success of deep neural networks owes much to three characteristics, ***-by-layer processing, in-model feature transformation and sufficient model complexity. On one hand,our conjecture may offer inspiration for theoretical understanding of deep learning; on the other hand, to verify the conjecture, we propose an approach that generates deep forest holding these characteristics. This is a decision-tree ensemble approach, with fewer hyper-parameters than deep neural networks, and its model complexity can be automatically determined in a data-dependent way. Experiments show that its performance is quite robust to hyper-parameter settings, such that in most cases, even across different data from different domains, it is able to achieve excellent performance by using the same default setting. This study opens the door to deep learning based on non-differentiable modules without gradient-based adjustment, and exhibits the possibility of constructing deep models without backpropagation.

关键词： deep forest deep learning machine learning ensemble methods decision trees

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

A preliminary study on ras protein expression in human esophageal cancer and precancerous lesions

引用

World Journal of Gastroenterology 2000年第2期6卷 278-280页

作者： Jian Li chang Wei feng Zhi Guo Zhao Qi zhou Li Dong Wang Department of Gastroenterology the 2nd Affiliated Hospital of Henan Medical UniversityZhengzhou 450003Henan ProvinceChina Laboratory for Cancer Research Henan Medical UniversityZhengzhou 450052Henan ProvinceChina

INTRODUCTIONThe esophageal carcinoma is a common malignanttumor in Linzhou City (Linxian) of Henan Provincein northern *** the etiology andnatural history of csophageal carcinoma are notclear,a substantial amount of evidence has beenprovided to suggest that the development of humanesophageal squamous cell carcinomas (SCC) is amultistage progressive ***

关键词： esophageal neoplasms ras protein oncogene gene expression precancerous condition

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Near-infrared dyes, nanomaterials and proteins

引用

Chinese Chemical Letters 2019年第10期30卷 1856-1882页

作者： Zong chang feng Liu Liang Wang Mengying Deng Chunhua zhou Qinchao Sun Jun Chu Laboratory for Biomedical Optics and Molecular Imaging Institute of Biomedical and Health EngineeringShenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China CAS Key Laboratory of Health Informatics Shenzhen Institute of Synthetic BiologyShenzhen-Hong Kong Institute of Brain ScienceShenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Taking the advantage of reduced scattering and low autofluorescence background, the NIR fluorescence probes, such as fluorescence proteins, organic molecules and nanoparticles, not only hold the promise of in vivo imaging of biological processes in physiology and pathology with high signal-to-noise ratio, but also for clinical diagnosis. In this review, we provide an overview of the recent progress on NIR probes,focusing on fundamental mechanisms of NIR dyes and nanoparticles, and protein engineering strategies for NIR proteins.

关键词： Near-infrared II Small organic dye Nanoparticles Near-infrared fluorescent protein Bacteriophytochrome Fluorogen

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Modular assembly of Co4-thiacalix[4]arene units and Keggin-type SiW12O40 for visible-light photothermal conversion

引用

Tungsten 2025年第1期 112-119页

作者： Jia-Hui Li Qing Zhao Dong-Ao Mao Kun zhou Bao-Kuan Chen Yan-feng Bi School of Petrochemical Engineering Liaoning Petrochemical University

The construction of metal-organic coordination clusters（MCCs） using modular secondary building units is an important method for preparing functional *** this study,two new MCCs modularly assembled from Keggin-type {SiW12O40}H4TC4A=p-tert-Butylthiacalix[4]arene(SiW12) units and thiacalixarene-supported Co4-thiacalix[4]arene(Co4-TC4A polynuclear second-building units（PSBUs,H4TC4A=p-tert-Butylthiacalix[4]arene） are *** two MCCs,abbreviated as Co4-SiW12and Co8-SiW12,were structurally characterized by single-crystal X-ray *** Co4-SiW12is a supramolecular structure involving cation-anion interactions between Co4-TC4A PSBUs and ***8-SiW12features "barbell-like" shapes with two Co4-TC4A coordinatively linked to a Keggin-type SiW12unit on opposite via W-O_t-Co *** coordination of Co4-TC4A to SiW12in Co8-SiW12resulted in significantly improved photothermal conversion performances compared with Co4-SiW12and pure SiW12or ***-gap determination and photophysical analysis combined with density functional theory calculations indicated the binding mode between Co4-TC4A PSBUs and SiW12,which considerably influences the way of electron transport and the conversion ability of visible light to heat.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Improving the off-resonance energy harvesting performance using dynamic magnetic preloading

引用

Acta Mechanica Sinica 2020年第3期36卷 624-634页

作者： feng Qian Shengxi zhou Lei Zuo Department of Mechanical Engineering Virginia TechBlacksburgVA 24061USA School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

Piezoelectric stack transducers in d33 mode have a much higher mechanical-to-electric energy conversion efficiency compared with d3l mode piezoelectric ***,multilayered piezoelectric stacks usually operate in off-resonance due to the higher stiffness and thereby have a lower power output under low-frequency *** paper proposes to apply the dynamic magnetic pre-loading to a piezoelectric stack transducer to significantly increase the power *** energy harvesting system consists of a multilayered piezoelectric stack with a compliant force amplification frame,a proof mass,and two magnets configured in *** static force-displacement relationship of the magnets is identified from experiments and extended to a dynamic model capable of characterizing the dynamic magnetic *** electromechanical model is developed based on the theoretical derivation and the experimentally identified parameters to predict the voltage outputs under different resistive *** analytical solutions are derived by using the harmonic balance method and show good agreements with the numerical and experimental *** performance of the system is examined and compared with that of the harvester without magnetic *** influences of the distance between the two magnets and the electrical resistive loads on the power output are *** indicate the energy harvesting system with magnetic pre-loading can produce over thousand times more power than the system without magnetic pre-loading at the base excitation of 3 Hz and 0.5 m/s……2,far below the resonance at 243 Hz.

关键词： Energy harvesting Piezoelectric Off-resonance Harmonic balance analysis Magnetic interaction

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

四线法弱发光样品绝对量子产率的测量

引用

光谱学与光谱分析 2025年第1期45卷 95-100页

作者：郑永丽张晓东周永丰上海交通大学化学与化工学院上海200240 上海珩翼行科技有限公司上海200235

弱发光样品量子产率测量困难,提出了四线法的测量方法,采用荧光光谱仪和积分球附件相结合的测量方式,主要利用衰减片的添加来实现样品荧光发射信号的相对增强,较大程度提高了弱发光样品量子产率测量的准确度。采用该装置测定了标准物质Y... 详细信息

弱发光样品量子产率测量困难,提出了四线法的测量方法,采用荧光光谱仪和积分球附件相结合的测量方式,主要利用衰减片的添加来实现样品荧光发射信号的相对增强,较大程度提高了弱发光样品量子产率测量的准确度。采用该装置测定了标准物质YG晶体的绝对量子产率为42.0%,相对误差0.95%,验证了荧光分光光度计和积分球结合的方式用于绝对量子产率测量的可行性。然后介绍了四线法用于绝对量子产率测量的依据、测量过程及数据处理方法。采用四线法测量了标准样品罗丹明6G和硫酸奎宁的绝对量子产率,结果显示相对误差分别为1.3%和1.1%,远小于5.0%(量子产率允许误差),表明该方法具有较高的准确性。详细探讨了实验条件对四线法绝对量子产率测量结果的影响,发现测试的最佳条件为衰减片放于激发端、衰减后的光源强度达到荧光光谱仪检测器光强线性响应区间的上限。采用不同浓度罗丹明6G溶液模拟弱发光、中强发光以及强发光样品,分别用二线法(常规方法)和四线法测量各溶液的绝对量子产率,将测试结果与文献报导数据对比,发现四线法更适用于弱发光和中强发光样品绝对量子产率的测量,尤其用于弱发光样品测量时,相对误差由二线法的10%降至四线法的0.32%。

关键词：绝对量子产率四线法衰减片弱发光样品标准样品

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：